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Publication
Journal: American Journal of Physiology - Regulatory Integrative and Comparative Physiology
March/23/2021
Abstract
Vitamin B12 deficiency has been shown to affect bone mass in rodents and negatively impact bone formation in humans. In this study using mouse models we define the effect of B12 supplementation in the wild-type mother and B12 deficiency in a mouse genetic model (Gif-/- mice) during gestation on the bone and muscle architecture, and mechanical properties in the offspring. Analysis of bones from 4 weeks-old offspring of the wild-type mother following vehicle or B12 supplementation during gestation (From embryonic day 0.5-20.5) showed an increase in bone mass caused by an isolated increase in bone formation in the B12 supplemented group compared to vehicle controls. Analysis of effect of B12 deficiency in the mother in a mouse genetic model (Gif-/- mice) on long bone architecture of the offspring showed a compromised cortical and trabecular bone mass, which was completely prevented by a single injection of B12 in the B12-deficient Gif-/- mothers.Biomechanical analysis of long bones of the offspring born from B12 supplemented wild-type mothers showed an increase in bone strength, and conversely offspring born from B12-deficient Gif-/- mothers revealed a compromised bone strength, which could be rescued by a single injection of B12 in the B12-deficient Gif-/- mother. Muscle structure and function analysis however revealed no significant effect on muscle mass, structure and grip strength of B12 deficiency or supplementation in Gif-/- mice compared to littermate controls. Together, these results demonstrate the beneficial effect of maternally-derived B12 in the regulation of bone structure and function in the offspring.
Keywords: Bone; Gut; Muscle; Osteoblasts; Vitamin B12.
Publication
Journal: Digestive Diseases and Sciences
March/1/2021
Abstract
Background: Gastrointestinal fistulization (GIF) is a rare and potentially fatal complication of acute necrotizing pancreatitis (ANP). There is paucity of data on clinical course and outcome of GIF in walled of necrosis (WON).
Objective: To evaluate frequency, clinical as well as imaging findings and outcome of spontaneous symptomatic GIF in patients with WON.
Methods: Retrospective analysis of database of patients with asymptomatic WON on regular follow-up over last six years to identify patients with symptomatic GIF.
Results: Out of 138 patients with asymptomatic WON seen during the study period, 16 (11.5%) patients (all males; mean age 41.7 ± 9.9 years) developed symptomatic GIF. The mean size of WON in patients who developed GIF was 9.5 ± 2.4 cm, and fistulization occurred after 65.1 ± 17.8 days of the onset of ANP. The site of fistulization was stomach, duodenum, jejunum, colon, and esophagus in seven (43.7%), five (31.2%), one (6.2%), two (12.5%), and one (6.2%) patients, respectively. GIF resulted in spontaneous resolution in two patients (stomach 1 and esophagus 1). The remaining patients with gastric (six patients) and duodenal (five patients) fistulization were successfully treated endoscopically by placing multiple plastic stents in the necrotic cavity after balloon dilatation of the fistulous tract. Patients with colonic fistulization required surgery. None of the patients succumbed to the illness.
Conclusion: Symptomatic GIF of WON usually occurs within the first three months of onset of ANP. It commonly occurs in either stomach or duodenum and can be successfully managed endoscopically.
Keywords: Computed tomography; Fistula; Pancreatic necrosis; Pancreatitis; Stent.
Publication
Journal: CoDAS
August/3/2021
Abstract
Purpose: To verify the effectiveness of the speech language intervention in the communicative behavior in group of individuals diagnosed with schizophrenia.
Methods: This is a semi-experimental, quantitative analytical-exploratory study. Users of a Psychosocial Care Center III (CAPS III) with a diagnosis of schizophrenia were included, divided into 2 groups: Experimental Group (EG), comprising the Speech Therapy Intervention Group (STIG) and Control Group (CG). The communicative behavior was evaluated through the Brief MAC Battery. The STIG was performed in 2 weekly sessions, during 12 weeks, totalizing 24 sessions. After this period, individuals were reassessed. Data were analyzed through Mann Whitney non-parametric Test, and Pearson's Correlation Test.
Results: A total of 19 individuals of both sexes participated, who are between 19 and 59 years old with a minimum schooling of 5 years, 14 participating in EG and 5 in CG. In the EG, it was possible to observe that there was improvement in the communicative behavior after the speech language intervention in all the tasks evaluated, except in the writing task. In CG, no significant changes were observed comparing evaluation and reevaluation after 12 weeks.
Conclusion: The speech-language intervention in group was effective as a socialization tool and contributing to the improvement of the living conditions of these people with schizophrenia.
Objetivo: Verificar a efetividade da intervenção fonoaudiológica grupal no comportamento comunicativo de indivíduos com diagnóstico de esquizofrenia.
Método: Trata-se de um estudo quase experimental, quantitativo analítico-exploratório. Foram incluídos usuários de um Centro de Atenção Psicossocial III (CAPS III) com diagnóstico de esquizofrenia, divididos em 2 grupos: Grupo Experimental (GE), compondo o Grupo de Intervenção Fonoaudiológica (GIF) e Grupo Controle (GC). O comportamento comunicativo foi avaliado através da Bateria MAC Breve. O GIF foi realizado em 2 sessões semanais, totalizando 24 sessões. Após esse período, os indivíduos foram reavaliados. A análise ocorreu por meio dos Testes não paramétricos de Mann Whitney e o Teste de Correlação de Pearson.
Resultados: Participaram 19 indivíduos, de ambos os sexos, com idade entre 19 e 59 anos, escolaridade mínima de 5 anos, sendo que 14 participaram do GE e 5 do GC. No GE, foi possível observar que houve melhora no comportamento comunicativo após a intervenção fonoaudiológica em todas as tarefas avaliadas, exceto na tarefa de Escrita. Já no GC, não foram observadas alterações significativas comparando a avaliação e a reavaliação após 12 semanas.
Conclusão: A intervenção fonoaudiológica grupal foi efetiva, utilizando a comunicação como instrumento de socialização e contribuindo para a melhoria das condições de vida de indivíduos com diagnóstico de esquizofrenia.
Publication
Journal: Health Psychology
November/3/2021
Abstract
Objective: Mobile technologies allow for accessible and cost-effective health monitoring and intervention delivery. Despite these advantages, mobile health (mHealth) engagement is often insufficient. While monetary incentives may increase engagement, they can backfire, dampening intrinsic motivations and undermining intervention scalability. Theories from psychology and behavioral economics suggest useful nonmonetary strategies for promoting engagement; however, examinations of the applicability of these strategies to mHealth engagement are lacking. This proof-of-concept study evaluates the translation of theoretically-grounded engagement strategies into mHealth, by testing their potential utility in promoting daily self-reporting.
Method: A microrandomized trial (MRT) was conducted with adolescents and emerging adults with past-month substance use. Participants were randomized multiple times daily to receive theoretically-grounded strategies, namely reciprocity (the delivery of inspirational quote prior to self-reporting window) and nonmonetary reinforcers (e.g., the delivery of meme/gif following self-reporting completion) to improve proximal engagement in daily mHealth self-reporting.
Results: Daily self-reporting rates (62.3%; n = 68) were slightly lower than prior literature, albeit with much lower financial incentives. The utility of specific strategies was found to depend on contextual factors pertaining to the individual's receptivity and risk for disengagement. For example, the effect of reciprocity significantly varied depending on whether this strategy was employed (vs. not employed) during the weekend. The nonmonetary reinforcement strategy resulted in different outcomes when operationalized in various ways.
Conclusions: While the results support the translation of the reciprocity strategy into this mHealth setting, the translation of nonmonetary reinforcement requires further consideration prior to inclusion in a full scale MRT. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
Trial registration: ClinicalTrials.gov NCT03255317.
Publication
Journal: British Journal of Neurosurgery
August/17/2021
Abstract
Background: The piriform cortex (PC) occupies both banks of the endorhinal sulcus and has an important role in the pathophysiology of temporal lobe epilepsy (TLE). A recent study showed that resection of more than 50% of PC increased the odds of becoming seizure free by a factor of 16.
Objective: We report the feasibility of manual segmentation of PC and application of the Geodesic Information Flows (GIF) algorithm to automated segmentation, to guide resection.
Methods: Manual segmentation of PC was performed by two blinded independent examiners in 60 patients with TLE (55% Left TLE, 52% female) with a median age of 35 years (IQR, 29-47 years) and 20 controls (60% Women) with a median age of 39.5 years (IQR, 31-49). The GIF algorithm was used to create an automated pipeline for parcellating PC which was used to guide excision as part of temporal lobe resection for TLE.
Results: Right PC was larger in patients and controls. Parcellation of PC was used to guide anterior temporal lobe resection, with subsequent seizure freedom and no visual field or language deficit.
Conclusion: Reliable segmentation of PC is feasible and can be applied prospectively to guide neurosurgical resection that increases the chances of a good outcome from temporal lobe resection for TLE.
Keywords: Epilepsy surgery; imaging; piriform cortex; segmentation; temporal lobe epilepsy.
Publication
Journal: Free Radical Biology and Medicine
August/17/2021
Abstract
Oxidative stress has been implicated in the aging process and the progression of many neurodegenerative disorders. We previously reported that a novel oxindole compound, GIF-0726-r, effectively prevents endogenous oxidative stress, such as oxytosis/ferroptosis, an iron-dependent form of non-apoptotic cell death, in mouse hippocampal cells. In this study, using two hundred compounds that were developed based on the structure-activity relationship of GIF-0726-r, we screened for the most potent compounds that prevent glutamate- and erastin-induced oxytosis and ferroptosis. Using submicromolar concentrations, we identified nine neuroprotective compounds that have N,N-dimethylaniline as a common structure but no longer contain an oxindole ring. The most potent derivatives, GIF-2114 and GIF-2197-r (the racemate of GIF-2115 and GIF-2196), did not affect glutathione levels, had no antioxidant activity in vitro, or ability to activate the Nrf2 pathway, but prevented oxytosis/ferroptosis via reducing reactive oxygen production and decreasing ferrous ions. Furthermore, we developed fluorescent probes of GIF-2114 and GIF-2197-r to image their distribution in live cells and found that they preferentially accumulated in late endosomes/lysosomes, which play a central role in iron metabolism. These results suggest that GIF-2114 and GIF-2197-r protect hippocampal cells from oxytosis/ferroptosis by targeting late endosomes and lysosomes, as well as decreasing ferrous ions.
Keywords: Ferroptosis; Lysosomes; N,N-dimethylaniline derivatives; Neurodegeneration; Neuroprotection; Oxytosis.
Publication
Journal: International Journal of General Medicine
August/10/2021
Abstract
Objective: This study attempted to screen and combine effective biomarkers to analyse the association between these biomarkers and gastrointestinal failure (GIF) in critically ill patients.
Methods: A total of 110 critically ill patients with acute gastrointestinal injury (AGI) admitted to ICU were enrolled. The AGI grade was determined by the AGI classification proposed by ESICM. There were 67 patients in gastrointestinal dysfunction (GID) group (AGI grade II), 43 patients in GIF group (AGI grade III-IV), and 41 healthy adults in healthy control (HC) group. APACHE II and SOFA score were used to evaluate the disease severity. Peripheral blood samples of patients were collected within 24 hours of admission to the ICU (prior-treatment) and after the conventional medication therapy for 7 consecutive days (post-treatment). Citrulline serum level was detected by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method, and D-lactate and lipopolysaccharide (LPS) serum levels were measured by ELISA. Pearson correlation, logistic regression, and ROC curve analysis were used.
Results: Patients with GID or GIF had lower serum level of citrulline, while higher levels of D-lactate and LPS than HC. Compared with GID patients, serum level of citrulline was reduced, while D-lactate and LPS were elevated in GIF patients. Correlation analysis displayed that serum levels of citrulline, D-lactate, and LPS were associated with the APACHE II and SOFA score in patients with GID or GIF. Logistics regression analysis showed that citrulline and D-lactate were risk for both GID and GIF. ROC curve analysis exhibited that combination of citrulline and D-lactate had relatively high value to distinguish GID from HC, GIF from GID, and GIF from HC.
Conclusion: Serum citrulline and D-lactate were associated with severity of GIF, combination of citrulline and D-lactate improved the diagnostic efficacy to identify GIF in critically ill patients.
Keywords: D-lactate; citrulline; critically ill patients; gastrointestinal dysfunction; gastrointestinal failure.
Publication
Journal: VideoGIE
August/16/2021
Abstract
Background and aims: We previously reported that 3 endoscopic findings of melanosis, whitish epithelium, and vasodilation in the soft palate are associated with a high risk of esophageal squamous cell carcinoma (ESCC). Conventional endoscopic systems require observation under magnification to evaluate vasodilation. This case series aims to present the evaluation of vasodilation without magnification using an endoscopic system with enhanced depth-of-field (EDOF) imaging.
Methods: We observed the soft palate of 3 patients with early ESCC using an endoscopic system with EDOF (GIF-EZ1500 and EVIS X1 CV-1500, Olympus Co, Tokyo, Japan).
Results: The patient in case 1 had marked melanosis, whitish epithelium, and vasodilation (focal type) in the soft palate. The patient in case 2 had melanosis and vasodilation (diffuse type) in the soft palate. The vasodilation in cases 1 and 2 could be evaluated sufficiently without magnification. The patient in case 3 had melanosis and whitish epithelium in the soft palate. The color tone of melanosis became sharpened using texture and color enhancement imaging.
Conclusions: The endoscopic system with EDOF enabled us to evaluate all 3 soft palate findings associated with a high risk of ESCC, without magnification.
Keywords: EDOF, enhanced depth-of-field; ER, endoscopic resection; ESCC, esophageal squamous cell carcinoma; NBI, narrow-band imaging; TXI, texture and color enhancement imaging.
Publication
Journal: Medical Physics
December/1/2021
Abstract
Purpose: High-resolution synchrotron radiation X-ray phase contrast microtomography (PC-μCT) images often suffer from severe ring artifacts, which are mainly caused by undesirable responses of detector elements. In the medical imaging field, the existence of ring artifacts can lead to degraded visual quality and can directly affect diagnosis accuracy. Thus, removing or at least effectively reducing ring artifacts is indispensable.
Method: The existing ring artifacts removal algorithms mainly focus on two-dimensional (matrix-based) priors, and these algorithms fail to consider correlations hidden in sequential CT images. This paper proposed a novel three-dimensional (tensor-based) ring artifacts removal algorithm for synchrotron radiation X-ray PC-μCT images. In the sinogram domain, ring artifacts manifest as vertical stripe artifacts. From an image decomposition perspective, a degraded sinogram can be decomposed into a stripe artifacts component and an underlying clean sinogram component. The proposed algorithm is designed to detect and remove stripe artifacts from a degraded sinogram by fully identifying the characteristics of the two components. Specifically, for the stripe artifacts component, tensor Tucker decomposition is used to describe its low-rank character. For the underlying clean sinogram component, spatial-sequential total variation regularization is adopted to enhance the piecewise smoothness. Moreover, the Frobenius norm term is further used to model Gaussian noise. An efficient augmented Lagrange multiplier method is designed to solve the proposed optimization model.
Results: The proposed method is evaluated utilizing both simulations and real data containing different ring artifacts patterns. In the simulations, the human chest CT images are used for evaluating the proposed method. We compare the peak signal-to-noise ratio (PSNR), structural similarity (SSIM), and mean absolute error (MAE) results of our algorithm with the Naghia's method, the RRRTV method, the Wavelet-FFT method, and the SDRSD-GIF method. The proposed method was also evaluated on real data from rat liver samples and rat tooth samples. Our proposed method outperforms the competing methods in terms of both qualitative and quantitative evaluation results. Additionally, the 3D visualization results were presented to make the ring artifacts removal effect more intuitive.
Conclusion: The experimental results on simulations and real data clearly demonstrated that the proposed algorithm can significantly improve the quality of PC-μCT images compared with the existing popular algorithms, and it has great potential to promote the application of high-resolution imaging for visualizing biological tissues. This article is protected by copyright. All rights reserved.
Keywords: 3D ring artifacts removaly; X-ray phase contrast microtomography; low-rank tensor decomposition.
Publication
Journal: Gut
September/8/2021
Abstract
Objective: Metaplasia arises from differentiated cell types in response to injury and is considered a precursor in many cancers. Heterogeneous cell lineages are present in the reparative metaplastic mucosa with response to injury, including foveolar cells, proliferating cells and spasmolytic polypeptide-expressing metaplasia (SPEM) cells, a key metaplastic cell population. Zymogen-secreting chief cells are long-lived cells in the stomach mucosa and have been considered the origin of SPEM cells; however, a conflicting paradigm has proposed isthmal progenitor cells as an origin for SPEM.
Design: Gastric intrinsic factor (GIF) is a stomach tissue-specific gene and exhibits protein expression unique to mature mouse chief cells. We generated a novel chief cell-specific driver mouse allele, GIF-rtTA. GIF-GFP reporter mice were used to validate specificity of GIF-rtTA driver in chief cells. GIF-Cre-RnTnG mice were used to perform lineage tracing during homoeostasis and acute metaplasia development. L635 treatment was used to induce acute mucosal injury and coimmunofluorescence staining was performed for various gastric lineage markers.
Results: We demonstrated that mature chief cells, rather than isthmal progenitor cells, serve as the predominant origin of SPEM cells during the metaplastic process after acute mucosal injury. Furthermore, we observed long-term label-retaining chief cells at 1 year after the GFP labelling in chief cells. However, only a very small subset of the long-term label-retaining chief cells displayed the reprogramming ability in homoeostasis. In contrast, we identified chief cell-originating SPEM cells as contributing to lineages within foveolar cell hyperplasia in response to the acute mucosal injury.
Conclusion: Our study provides pivotal evidence for cell plasticity and lineage contributions from differentiated gastric chief cells during acute metaplasia development.
Keywords: gastric epithelial cell function; gastric metaplasia; mucosal injury.
Publication
Journal: IEEE Transactions on Biomedical Engineering
September/26/2021
Abstract
Hyper-reflective foci (HRF) refers to the spot-shaped, block-shaped areas with characteristics of high local contrast and high reflectivity, which is mostly observed in retinal optical coherence tomography (OCT) images of patients with fundus diseases. HRF mainly appears hard exudates (HE) and microglia (MG) clinically. Accurate segmentation of HE and MG is essential to alleviate the harm in retinal diseases. However, it is still a challenge to segment HE and MG simultaneously due to similar pathological features, various shapes and location distribution, blurred boundaries, and small morphology dimensions. To tackle these problems, in this paper, we propose a novel global information fusion and dual decoder collaboration-based network (GD-Net), which can segment HE and MG in OCT images jointly. Specifically, to suppress the interference of similar pathological features, a novel global information fusion (GIF) module is proposed, which can aggregate the global semantic information efficiently. To further improve the segmentation performance, we design a dual decoder collaborative workspace (DDCW) to comprehensively utilize the semantic correlation between HE and MG while enhancing the mutual influence on them by feedback alternately. To further optimize GD-Net, we explore a joint loss function which integrates pixel-level with image-level. The dataset of this study comes from patients diagnosed with diabetic macular edema at the department of ophthalmology, University Medical Center Groningen, the Netherlands. Experimental results show that our proposed method performs better than other state-of-the-art methods, which suggests the effectiveness of the proposed method and provides research ideas for medical applications.
Publication
Journal: Optics Express
October/6/2021
Abstract
Using fusion splicing and hydroxide catalysis bonding (HCB) technology, an all-silica inline fiber-optic sensor with high-pressure survivability, high-resolution salinity measurement capability, and corrosion resistance for deep sea explorations is proposed and experimentally demonstrated. Two extrinsic Fabry-Perot interferometers (EFPIs) and a fiber Bragg grating (FBG) are cascaded in one single-mode fiber (SMF), enabling structural integration of single lead-in fiber and versatility of the sensing probe for temperature, depth, and salinity monitoring. The HCB technology offers a polymer adhesive-free assembly of one open-cavity EFPI for refractive index (RI) (salinity) sensing under normal pressure and temperature (NPT) conditions, showing obvious advantages of strong bonding strength, reliable effectiveness, and no corrosive chemicals requirements. The other EFPI formed by a fused structure is designed for pressure (depth) measurement. The cascading of EFPIs, especially the open-cavity EFPI immersed in water, will result in large light transmission loss and bring challenges to signal interrogation. Graded-index fiber (GIF) micro-collimators and reflective films are added to prevent dramatic degradations of signal intensity and fringe visibility underwater. Thereby, a Fabry-Perot (FP) cavity of several hundreds of microns in length and an open cavity of a thousand microns can be cascaded for underwater applications, effectively enhancing sensitivities and underwater signal readout simultaneously. Results show that the proposed sensor can well operate in the deep-sea pressure range of 0∼2039.43 mH2O, RI range of 1.33239∼1.36885 RIU, and temperature range of 23∼80 °C, with resolutions of 0.033 MPa, 4.16×10-7 RIU, and 0.54 °C, respectively. With the multi-parameter measurement capability, all-silica construction, and inline compact structure, the proposed sensor could be a potential candidate for deep sea exploration.
Publication
Journal: PLoS Genetics
October/7/2021
Abstract
The yeast-to-hypha transition is tightly associated with pathogenicity in many human pathogenic fungi, such as the model fungal pathogen Cryptococcus neoformans, which is responsible for approximately 180,000 deaths annually. In this pathogen, the yeast-to-hypha transition can be initiated by distinct stimuli: mating stimulation or glucosamine (GlcN), the monomer of cell wall chitosan. However, it remains poorly understood how the signal specificity for Cryptococcus morphological transition by disparate stimuli is ensured. Here, by integrating temporal expression signature analysis and phenome-based clustering evaluation, we demonstrate that GlcN specifically triggers a unique cellular response, which acts as a critical determinant underlying the activation of GlcN-induced filamentation (GIF). This cellular response is defined by an unusually hyperactive cell wall synthesis that is highly ATP-consuming. A novel cell surface protein Gis1 was identified as the indicator molecule for the GlcN-induced cell wall response. The Mpk1-directed cell wall pathway critically bridges global cell wall gene induction and intracellular ATP supply, ensuring the Gis1-dependent cell wall response and the stimulus specificity of GIF. We further reveal that the ability of Mpk1 to coordinate the cell wall response and GIF activation is conserved in different Cryptococcus pathogens. Phosphoproteomics-based profiling together with genetic and phenotypic analysis revealed that the Mpk1 kinase mediates the regulatory specificity of GIF through a coordinated downstream regulatory network centered on Skn7 and Crz1. Overall, our findings discover an unprecedented and conserved cell wall biosynthesis-dependent fungal differentiation commitment mechanism, which enables the signal specificity of pathogenicity-related dimorphism induced by GlcN in Cryptococcus pathogens.
Publication
Journal: Applied Optics
October/5/2021
Abstract
Endoscopic optical coherence tomography of large airways poses unique challenges. A hybrid lens is described that consists of a section of coreless fiber and graded index fiber (GIF), followed by a ball lens section. This design produces low numerical aperture beams better suited for large airway imaging. The performance of this lens is compared against conventional GIF and ball lens designs. Forward- and side-viewing probes were modeled, fabricated, and tested. The impact of a sheath on the beam profile was also investigated. Probes with working distances larger than 10 mm and depth-of-focus exceeding 12 mm are demonstrated with the proposed design.
Publication
Journal: Surgical Endoscopy
October/12/2021
Abstract
Introduction: Several techniques for PEG-J tube placement have been described, commonly requiring fluoroscopic guidance and/or fixation of the jejunostomy tube (J-tube) into the small intestine. We describe a modified technique for placing jejunostomy tubes under direct visualization through a PEG with the use of ultra-thin endoscopes and steel guidewire.
Methods: A retrospective study at a single tertiary academic center evaluating patients who underwent PEG-J placement between 2010 and 2020. All PEG tubes were placed with a pull-through technique. The Olympus GIF-N180 endoscope was advanced through the PEG to the jejunum and a Savary-Gilliard guidewire was used for placement of the J-tube extension.
Results: Fifty-eight patients underwent PEG-J placement (median age 61 years; women 52%). Surgically altered gastric anatomy was observed in 11 patients (19%). Median procedure time was 44 min for new PEG-J tube placement (range 26-103) and 20 min for placement of a J-tube extension through an existing PEG tube (range 9-86) or gastrostomy tract. Technical success rate was in 100%. Sixty-two repeat procedures were performed for J-tube exchange in 27 patients (46%, range 1-9 per patient), of which 51 procedures (82%) were done using the same technique. The most common indication for tube replacement was tube dysfunction (63%, n = 39). The median procedure time for tube exchange was 20 min (range 2-62). No major adverse events were encountered.
Conclusion: PEG-J tubes can be placed effectively, rapidly, and safely using an ultra-thin caliber endoscope and a stiff steel wire through the PEG tube or mature gastrostomy site, precluding the need for fluoroscopy or oral access. J-tubes can be easily replaced utilizing the same technique.
Keywords: Aspiration; Jejunostomy tubes; N180 endoscope; Savary-Gilliard guidewire.
Publication
Journal: Molecular Ecology
October/21/2021
Abstract
The crustacean marine isopod species Haploniscus bicuspis (Sars, 1877) shows circum-Icelandic distribution in a wide range of environmental conditions and along well-known geographic barriers, such as the Greenland-Iceland-Faroe (GIF) Ridge. We wanted to explore population genetics, phylogeography and cryptic speciation as well as investigate whether previously described, but unaccepted subspecies have any merit. Using the same set of specimens, we combined mitochondrial COI sequences, thousands of nuclear loci (ddRAD), and proteomic profiles, plus selected morphological characters using confocal laser scanning microscopy (CLSM). Five divergent genetic lineages were identified by COI and ddRAD, two south and three north of the GIF Ridge. Assignment of populations to the three northern lineages varied and detailed analyses revealed hybridization and gene flow between them, suggesting a single northern species with a complex phylogeographic history. No apparent hybridization was observed among lineages south of the GIF Ridge, inferring the existence of two more species. Differences in proteomic profiles between the three putative species were minimal, implying an ongoing or recent speciation process. Population differentiation was high, even among closely associated populations, and higher in mitochondrial COI than nuclear ddRAD loci. Gene flow is apparently male-biased, leading to hybrid zones and instances of complete exchange of the local nuclear genome through immigrating males. This study did not confirm the existence of subspecies defined by male characters, which probably instead refer to different male developmental stages.
Keywords: Haploniscus bicuspis; DNA barcoding; Haploniscidae; MALDI-TOF; cryptic species; ddRAD.
Publication
Journal: Big Data
October/31/2021
Abstract
For the segmentation of magnetic resonance brain images into anatomical regions, numerous fully automated methods have been proposed and compared to reference segmentations obtained manually. However, systematic differences might exist between the resulting segmentations, depending on the segmentation method and underlying brain atlas. This potentially results in sensitivity differences to disease and can further complicate the comparison of individual patients to normative data. In this study, we aim to answer two research questions: 1) to what extent are methods interchangeable, as long as the same method is being used for computing normative volume distributions and patient-specific volumes? and 2) can different methods be used for computing normative volume distributions and assessing patient-specific volumes? To answer these questions, we compared volumes of six brain regions calculated by five state-of-the-art segmentation methods: Erasmus MC (EMC), FreeSurfer (FS), geodesic information flows (<em>GIF</em>), multi-atlas label propagation with expectation-maximization (MALP-EM), and model-based brain segmentation (MBS). We applied the methods on 988 non-demented (ND) subjects and computed the correlation (PCC-v) and absolute agreement (ICC-v) on the volumes. For most regions, the PCC-v was good ( <math><mrow><mo>></mo> <mn>0.75</mn></mrow> </math> ), indicating that volume differences between methods in ND subjects are mainly due to systematic differences. The ICC-v was generally lower, especially for the smaller regions, indicating that it is essential that the same method is used to generate normative and patient data. To evaluate the impact on single-subject analysis, we also applied the methods to 42 patients with Alzheimer's disease (AD). In the case where the normative distributions and the patient-specific volumes were calculated by the same method, the patient's distance to the normative distribution was assessed with the z-score. We determined the diagnostic value of this z-score, which showed to be consistent across methods. The absolute agreement on the AD patients' z-scores was high for regions of thalamus and putamen. This is encouraging as it indicates that the studied methods are interchangeable for these regions. For regions such as the hippocampus, amygdala, caudate nucleus and accumbens, and globus pallidus, not all method combinations showed a high ICC-z. Whether two methods are indeed interchangeable should be confirmed for the specific application and dataset of interest.
Keywords: brain region segmentation; comparison study; magnetic resonance imaging; normative modeling; subcortical.
Publication
Journal: International Journal of Molecular Sciences
October/12/2021
Abstract
Forest tree breeding efforts have focused mainly on improving traits of economic importance, selecting trees suited to new environments or generating trees that are more resilient to biotic and abiotic stressors. This review describes various methods of forest tree selection assisted by genomics and the main technological challenges and achievements in research at the genomic level. Due to the long rotation time of a forest plantation and the resulting long generation times necessary to complete a breeding cycle, the use of advanced techniques with traditional breeding have been necessary, allowing the use of more precise methods for determining the genetic architecture of traits of interest, such as genome-wide association studies (GWASs) and genomic selection (GS). In this sense, main factors that determine the accuracy of genomic prediction models are also addressed. In turn, the introduction of genome editing opens the door to new possibilities in forest trees and especially clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9 (CRISPR/Cas9). It is a highly efficient and effective genome editing technique that has been used to effectively implement targetable changes at specific places in the genome of a forest tree. In this sense, forest trees still lack a transformation method and an inefficient number of genotypes for CRISPR/Cas9. This challenge could be addressed with the use of the newly developing technique GRF-GIF with speed breeding.
Keywords: BLUP; Bayesian genomic prediction; CRISPR/Cas9; GRF-GIF; forest tree improvement.
Publication
Journal: Molecules
January/10/2022
Abstract
Melanogenesis and melanosome secretion are regulated by several mechanisms. In this study, we found that the oxindole derivative GIF-2209 accelerated melanogenesis associated with the discrimination in the expression and intracellular distributions of two melanogenic enzymes, tyrosinase (TYR) and tyrosinase-related protein-1 (TYRP-1). GIF-2209 upregulated the expression of TYR via a microphthalmia transcription factor (MITF)-independent mechanism, leading to high expression of protein. In contrast, GIF-2209 did not alter the mRNA levels of TYRP-1 and suppressed its protein levels. GIF-2209 induced the dissociation of TYR from TYRP-1 but did not alter the association between TYR and CD63, a melanosome and lysosome marker. The protein levels of CD63 were also upregulated by GIF-2209. GIF-2209 induced lysosome expansion and redistribution in all areas of the cytosol, accompanied by autophagy acceleration (upregulation of LC3BII protein levels and downregulation of p62 protein levels). In addition, GIF-2209 stimulated the secretion of melanosomes containing high levels of TYR, TYRP-1, and CD63 proteins. The GIF-2209 mediated melanosome secretion was sensitive to the lysosome inhibitor chloroquine. These results suggest that GIF-2209 may activate lysosomal functions with TYR gene expression, while it accelerates melanosome secretion, which finally leads to the depletion of intracellular melanogenic enzyme, especially TYRP-1 protein.
Keywords: B16F10; SU5205; TYRP-1; lysosome; melanogenesis; melanosome; oxindole; tyrosinase.
Publication
Journal: Frontiers in Medicine
January/26/2022
Abstract
Aims: We investigated whether faecal microbiota transplantation (FMT) decreases intra-abdominal pressure (IAP) and improves gastrointestinal (GI) dysfunction and infectious complications in acute pancreatitis (AP). Methods: In this first randomised, single-blind, parallel-group, controlled study, we recruited and enrolled consecutive patients with AP complicated with GI dysfunction. Eligible participants were randomly assigned to receive faecal transplant (n = 30) or normal saline (n = 30) via a nasoduodenal tube once and then again 2 days later. The primary endpoint was the rate of IAP decline; secondary endpoints were GI function, infectious complications, organ failure, hospital stay and mortality. Analyses were based on intention to treat. Results: We enrolled 60 participants and randomly assigned them to the FMT (n = 30) or control (n = 30) group. Baseline characteristics and disease severity were similar for both groups. IAP decreased significantly 1 week after intervention in both groups, with no difference in the IAP decline rate between FMT and Control group [0.1 (-0.6, 0.5) vs. 0.2 (-0.2, 0.6); P = 0.27]. Normal gastrointestinal failure (GIF) scores were achieved in 12 (40%) patients in the FMT group and 14 (47%) in the control group, with no significant difference (P = 0.60). However, D-lactate was significantly elevated in the FMT group compared to the control group, as calculated by the rate of decline [-0.3 (-3.7, 0.8) vs. 0.4 (-1.1, 0.9); P = 0.01]. Infectious complications occurred in 15 (50%) and 16 (53.33%) patients in the FMT and control groups, respectively (P = 0.80). However, interleukin-6 (IL-6) was significantly elevated in the FMT group compared to the control group, as calculated by the rate of decline [0.4 (-3.6, 0.9) vs. 0.8 (-1.7, 1.0); P = 0.03]. One participant experienced transient nausea immediately after FMT, but no serious adverse events were attributed to FMT. Conclusion: FMT had no obvious effect on IAP and infectious complications in AP patients, though GI barrier indictors might be adversely affected. Further multi-centre studies are needed to confirm our findings. The study was registered at https://clinicaltrials.gov (NCT02318134).
Keywords: acute pancreatitis; faecal microbiota transplantation; gastrointestinal dysfunction; gut microbiota dysbiosis; infected pancreatic necrosis.
Publication
Journal: Frontiers in Plant Science
January/27/2022
Abstract
Rice Growth-Regulating Factors (GRFs) were originally identified to be gibberellin (GA)-induced, but the nature of GA induction has remained unknown because most reports thereafter focused on revealing their roles in growth-promoting activities. GRFs have the WRC (Trp, Arg, Cys) domain to target DNA and contain the QLQ (Gln, Leu, Gln) domain to interact with GRF-Interacting Factor (GIF), which recruits ATP-dependent DNA translocase Switch/Sucrose Non-fermenting (SWI/SNF) for chromatin remodeling. Both GRFs and GIFs exhibit transcriptional activities but GIFs lack a DNA-binding domain. So, GRFs act like a navigator in the GRF-GIF-SWI/SNF complex, determining when and where the complex should work on. The levels of most rice GRFs can be sensitively regulated by miR396, which responds to many developmental and environmental factors. Recent clues from several studies highlight the original question of how GRFs participate in GA signaling. DELLA (contain DELLA motif) protein plays dual roles in controlling the level of GRFs by regulating the level of miR396 and interacting with GRFs. Here we address the question of why this complex plays an essential role in controlling plant growth focusing on the action of GA signaling pivot, DELLA.
Keywords: DELLA; GA signaling; GIF; GRF; SWI/SNF.
Results with error correction
Publication
Journal: Brain
January/3/2001
Abstract
In most people the left hemisphere of the brain is dominant for language. Because of the increased incidence of atypical right-hemispheric language in left-handed neurological patients, a systematic association between handedness and dominance has long been suspected. To clarify the relationship between handedness and language dominance in healthy subjects, we measured lateralization directly by functional transcranial Doppler sonography in 326 healthy individuals using a word-generation task. The incidence of right-hemisphere language dominance was found to increase linearly with the degree of left-handedness, from 4% in strong right-handers (handedness = 100) to 15% in ambidextrous individuals and 27% in strong left-handers (handedness = -100). The relationship could be approximated by the formula: f1.gif" BORDER="0">. These results clearly demonstrate that the relationship between handedness and language dominance is not an artefact of cerebral pathology but a natural phenomenon.
Publication
Journal: Neuron
September/19/1991
Abstract
We have purified and characterized the growth inhibitory factor (GIF) that is abundant in the normal human brain, but greatly reduced in the Alzheimer's disease (AD) brain. GIF inhibited survival and neurite formation of cortical neurons in vitro. Purified GIF is a 68 amino acid small protein, and its amino acid sequence is 70% identical to that of human metallothionein II with a 1 amino acid insert and a unique 6 amino acid insert in the NH2-terminal and the COOH-terminal portions, respectively. The antibodies to the unique sequence of GIF revealed a distinct subset of astrocytes in the gray matter that appears to be closely associated with neuronal perikarya and dendrites. In the AD cortex, the number of GIF-positive astrocytes was drastically reduced, suggesting that GIF is down-regulated in the subset of astrocytes during AD.
Publication
Journal: European Heart Journal
May/21/2006
Abstract
OBJECTIVE
To examine the heritability of atrial fibrillation (AF) in Icelanders, utilizing a nationwide genealogy database and population-based data on AF. AF is a disorder with a high prevalence, which has been known to cluster in families, but the heritability of the common form has not been well defined.
RESULTS
The study population included 5269 patients diagnosed since 1987 and age-sex-matched controls randomly selected from the genealogy database. Kinship coefficients (KC), expressed as genealogical index of familiality (GIF = average KC x 100,000), were calculated before and after exclusion of relatives separated by one to five meiotic events. Risk ratios (RR) were calculated for first- to fifth-degree relatives. The average pairwise GIF among patients with AF was 15.9 (mean GIF for controls 13.9, 95%CI = 13.3, 14.4); this declined to 15.4 (mean GIF for controls 13.6, 95%CI = 13.1, 14.2) after exclusion of relatives separated by one meiosis and to 13.7 (mean GIF for controls 12.6, 95%CI = 12.1, 13.2), 12.7 (mean GIF for controls 11.9, 95%CI = 11.4, 12.4), and 11.3 (mean GIF for controls 10.6, 95%CI = 10.1, 11.1) after exclusion of relatives within two, three, and four meioses, respectively (all P<0.00001). RRs among relative pairs also declined incrementally, from 1.77 in first-degree relatives to 1.36, 1.18, 1.10, and 1.05 in second- through fifth-degree relatives (all P<0.001), consistent with the declining proportion of alleles shared identically by descent. When the analysis was limited to subjects diagnosed with AF before the age of 60, first-degree relatives of the AF cases were nearly five times more likely to have AF than the general population.
CONCLUSIONS
AF shows strong evidence of heritability among unselected patients in Iceland, suggesting that there may be undiscovered genetic variants underlying the risk of the common form of AF.
Publication
Journal: Journal of Biological Chemistry
December/3/2001
Abstract
The regulatory circuits that control nitrogen metabolism are relatively well known in several bacterial model groups. However, much less is understood about how the nitrogen status of the cell is perceived in vivo. In cyanobacteria, the transcription factor NtcA is required for regulation (activation or repression) of an extensive number of genes involved in nitrogen metabolism. In contrast, how NtcA activity is regulated is largely unknown. Assimilation of ammonium by most microorganisms occurs through the sequential action of two enzymes: glutamine synthetase (GS) and glutamate synthase. Interestingly, regulation of the expression of NtcA-dependent genes in the cyanobacterium Synechocystis sp. PCC 6803 is altered in mutants with modified levels of GS activity. Two types of mutants were analyzed: glnA null mutants that lack GS type I and gif mutants unable to inactivate GS in the presence of ammonium. Changes in the intracellular pools of 19 different amino acids and the keto acid 2-oxoglutarate were recorded in wild-type and mutant strains under different nitrogen conditions. Our data strongly indicate that the nitrogen status in cyanobacteria is perceived as changes in the intracellular 2-oxoglutarate pool.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
September/29/2004
Abstract
Previously, we described the AtGRF [Arabidopsis thaliana growth-regulating factor (GRF)] gene family, which encodes putative transcription factors that play a regulatory role in growth and development of leaves and cotyledons. We demonstrate here that the C-terminal region of GRF proteins has transactivation activity. In search of partner proteins for GRF1, we identified another gene family, GRF-interacting factor (<em>GIF</em>), which comprises three members. Sequence and molecular analysis showed that <em>GIF</em>1 is a functional homolog of the human SYT transcription coactivator. We found that the N-terminal region of <em>GIF</em>1 protein was involved in the interaction with GRF1. To understand the biological function of <em>GIF</em>1, we isolated a loss-of-function mutant of <em>GIF</em>1 and prepared transgenic plants subject to <em>GIF</em>1-specific RNA interference. Like grf mutants, the gif1 mutant and transgenic plants developed narrower leaves and petals than did wild-type plants, and combinations of gif1 and grf mutations showed a cooperative effect. The narrow leaf phenotype of gif1, as well as that of the grf triple mutant, was caused by a reduction in cell numbers along the leaf-width axis. We propose that GRF1 and <em>GIF</em>1 act as transcription activator and coactivator, respectively, and that they are part of a complex involved in regulating the growth and shape of leaves and petals.
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Publication
Journal: Gut
February/19/2003
Abstract
BACKGROUND
The presence of intestinal metaplasia (IM) in the columnar lined distal oesophagus defines Barrett's oesophagus with the risk of future malignant transformation. The distribution of both IM and dysplasia (low grade (LGD) and high grade (HGD)) within the columnar lined oesophagus is patchy and mosaic requiring random biopsies. Techniques that could help target areas of high yield within Barrett's mucosa would be helpful.
OBJECTIVE
To study the utility of high magnification chromoendoscopy (MCE) in the detection of IM, LGD, and HGD in patients with Barrett's oesophagus.
METHODS
Consecutive patients detected with columnar mucosa in the distal oesophagus were studied using an Olympus magnification endoscope (GIF-Q16OZ, 115x). The distal oesophagus was sprayed with indigo carmine solution and the oesophageal columnar mucosa patterns were noted under high magnification and targeted for biopsy. All biopsies were read by pathologists blinded to the endoscopic findings.
RESULTS
Eighty patients with suspected Barrett's oesophagus (that is, columnar lined distal oesophagus) were studied: mean age 62.7 years (range 35-81). Mean length of columnar mucosa was 3.7 cm (range 0.5-17). Three types of mucosal patterns were noted within the columnar mucosa after spraying indigo carmine and using MCE: ridged/villous pattern, circular pattern, and irregular/distorted pattern. The yield of IM on target biopsies according to the patterns was: ridged/villous 57/62 (97%) and circular 2/12 (17%). Six patients had an irregular/distorted pattern and all had HGD on biopsy (6/6 (100%)). Eighteen patients had LGD on target biopsies; all had the ridged/villous pattern. All patients with long segment Barrett's were identified using MCE whereas 23/28 patients (82%) with short segment Barrett's had the ridged/villous pattern.
CONCLUSIONS
MCE helps visually identify areas with IM and HGD having specific patterns but not patients with LGD (appear similar to IM). MCE may be a useful clinical tool for the increased detection of patients with IM as well as for surveillance of patients for the detection of HGD. If these preliminary results are validated, MCE would help identify high yield areas, potentially eliminating the need for random biopsies.
Publication
Journal: Biology of Reproduction
December/20/1999
Abstract
Cyritestin is a membrane-anchored sperm protein belonging to the ADAM (f1.gif" BORDER="0"> f2.gif" BORDER="0">isintegrin and f1.gif" BORDER="0"> f3.gif" BORDER="0">etalloprotease) family of proteins, which are proposed to be involved in cell-cell adhesion through binding to integrin receptors. Several lines of evidence support a role of cyritestin and other members of this protein family in the fusion of sperm and the egg plasma membrane. In an effort to elucidate the physiological function of cyritestin, we have disrupted its locus by homologous recombination. Male homozygous null mutants are infertile, even though spermatogenesis, mating, and migration of sperm from the uterus into the oviduct are normal. In vitro experiments showed that infertility is due to the inability of the cyritestin-deficient sperm to bind to the zona pellucida. However, after removal of the zona pellucida, sperm-egg membrane fusion monitored by the presence of pronuclei and generation of 2- and 4-cell embryos did not reveal any differences from the wild-type situation. These results demonstrate that cyritestin is crucial in the fertilization process at the level of the sperm-zona pellucida interaction.
Publication
Journal: Circulation
June/13/2001
Abstract
BACKGROUND
In patients with chronic heart failure (CHF) and preserved exercise tolerance, the value of cardiopulmonary exercise testing for risk stratification is not known. Elevated slope of ventilatory response to exercise (VE/VCO(2)) predicts poor prognosis in advanced CHF. Derangement of cardiopulmonary reflexes may trigger exercise hyperpnea. We assessed the relationship between cardiopulmonary reflexes and VE/VCO(2)and investigated the prognostic value of (VE/VCO(2)) in CHF patients with preserved exercise tolerance.
RESULTS
Among 344 consecutive CHF patients, we identified 123 with preserved exercise capacity, defined as a peak oxygen consumption (PEAK VO(2))>>/=18 mL. kg(-1). min(-1) (age 56 years; left ventricular ejection fraction 28%; peak VO(2) 23.5 mL. kg(-1). min(-1)). Hypoxic and hypercapnic chemosensitivity (n=38), heart rate variability (n=34), baroreflex sensitivity (n=20), and ergoreflex activity (n=20) were also assessed. We identified 40 patients (33%) with high VE/VCO(2) (ie, >34.0). During follow-up (49+/-22 months, >3 years in all survivors), 34 patients died (3-year survival 81%). High VE/VCO(2) (hazard ratio 4.3, P<0.0001) but not peak f1.gif" BORDER="0">O(2) (P=0.7) predicted mortality. In patients with high VE/VCO(2), 3-year survival was 57%, compared with 93% in patients with normal VE/VCO(2) P<0.0001). Patients with high VE/VCO(2) demonstrated impaired reflex control, as evidenced by augmented peripheral (P=0.01) and central (P=0.0006) chemosensitivity, depressed low-frequency component of heart rate variability (P<0.0001) and baroreflex sensitivity (P=0.03), and overactive ergoreceptors (P=0.003) compared with patients with normal VE/VCO(2).
CONCLUSIONS
In CHF patients with preserved exercise capacity, enhanced ventilatory response to exercise is a simple marker of a widespread derangement of cardiovascular reflex control; it predicts poor prognosis, which VO(2) does not.
Publication
Journal: Oncogene
April/22/2003
Abstract
NF-kappa B regulates normal and pathological processes, including neoplasia, in a tissue-context-dependent manner. In skin, NF-kappa B is implicated in epidermal homeostasis as well as in the pathogenesis of squamous cell carcinoma; however, its function in the underlying mesenchymal dermis has been unclear. To gain insight into NF-kappa B roles in these two adjacent cutaneous tissue compartments, NF-kappa B effects on expression of 12 435 genes were determined in epidermal keratinocytes and dermal fibroblasts. Although NF-kappa B induced proinflammatory and antiapoptotic genes in both settings, it exhibited divergent effects on growth regulatory genes. In keratinocytes, but not in fibroblasts, NF-kappa B induced p21(CIP1), which was sufficient to inhibit growth of both cell types. Levels of growth inhibitory factor (GIF), in contrast, were increased by NF-kappa B in both settings but inhibited growth only in keratinocytes. These findings indicate that transcription factors such as NF-kappa B can program tissue-selective effects via both differential target gene induction as well as by inducing common targets that exert differing effects depending on cellular lineage.
Publication
Journal: Journal of Korean Medical Science
November/5/2009
Abstract
Mesenchymal stem cells (MSCs) are capable of self-renewal and differentiation into lineages of mesenchymal tissues that are currently under investigation for a variety of therapeutic applications. The purpose of this study was to compare cytokine gene expression in MSCs from human placenta, cord blood (CB) and bone marrow (BM). The cytokine expression profiles of MSCs from BM, CB and placenta (amnion, decidua) were compared by proteome profiler array analysis. The cytokines that were expressed differently, in each type of MSC, were analyzed by real-time PCR. We evaluated 36 cytokines. Most types of MSCs had a common expression pattern including MIF (GIF, DER6), IL-8 (CXCL8), Serpin E1 (PAI-1), GROalpha(CXCL1), and IL-6. MCP-1, however, was expressed in both the MSCs from the BM and the amnion. sICAM-1 was expressed in both the amnion and decidua MSCs. SDF-1 was expressed only in the BM MSCs. Real-time PCR demonstrated the expression of the cytokines in each of the MSCs. The MSCs from bone marrow, placenta (amnion and decidua) and cord blood expressed the cytokines differently. These results suggest that cytokine induction and signal transduction are different in MSCs from different tissues.
Publication
Journal: Nucleic Acids Research
March/15/2007
Abstract
ParameciumDB (http://paramecium.cgm.cnrs-gif.fr) is a new model organism database associated with the genome sequencing project of the unicellular eukaryote Paramecium tetraurelia. Built with the core components of the Generic Model Organism Database (GMOD) project, ParameciumDB currently contains the genome sequence and annotations, linked to available genetic data including the Gif Paramecium stock collection. It is thus possible to navigate between sequences and stocks via the genes and alleles. Phenotypes, of mutant strains and of knockdowns obtained by RNA interference, are captured using controlled vocabularies according to the Entity-Attribute-Value model. ParameciumDB currently supports browsing of phenotypes, alleles and stocks as well as querying of sequence features (genes, UniProt matches, InterPro domains, Gene Ontology terms) and of genetic data (phenotypes, stocks, RNA interference experiments). Forms allow submission of RNA interference data and some bioinformatics services are available. Future ParameciumDB development plans include coordination of human curation of the near 40 000 gene models by members of the research community.
Publication
Journal: Journal of Virology
August/18/1991
Abstract
Although the number of antigenic sites on the rabies virus glycoprotein that have been described regularly increases with time, no attempt has been made to carefully evaluate the relative importance of each of these sites. Here we provide a more precise description of the antigenicity of the protein in mice of the H-2d haplotype; we developed this description by using 264 newly isolated monoclonal antibodies (MAbs) and a collection of neutralization-resistant (MAR) mutants. Most of the MAbs (97%) recognized antigenic sites previously described as II and III. One minor antigenic site separated from site III by three amino acids, including a proline, was identified (minor site a). Despite their proximity, there is no overlap between site III and minor site a; i.e., site III-specific MAR mutants were neutralized by the six MAbs defining minor site a, and vice versa. One of our MAbs, 1D1, reacted with sodium dodecyl sulfate-treated glycoprotein in Western blots (immunoblots) under reducing conditions and was therefore probably directed against a linear epitope, A MAR mutant selected with this MAb was still neutralized by MAbs of other specificities. This linear epitope was called G1 (G, Gif). As a general rule, we propose to reserve the term "antigenic site" (either major or minor) for regions of the protein which are defined by several MAbs originating from different fusions and to describe regions of the protein which are defined by a single MAb as epitopes. It would be interesting to test whether the same regions of the rabies virus glycoprotein are antigenic in mice of different haplotypes or in other species.
Publication
Journal: Journal of Neurophysiology
March/25/2002
Abstract
All linear accelerometers measure gravitoinertial force, which is the sum of gravitational force (tilt) and inertial force due to linear acceleration (translation). Neural strategies must exist to elicit tilt and translation responses from this ambiguous cue. To investigate these neural processes, we developed a model of human responses and simulated a number of motion paradigms used to investigate this tilt/translation ambiguity. In this model, the separation of GIF into neural estimates of gravity and linear acceleration is accomplished via an internal model made up of three principal components: 1) the influence of rotational cues (e.g., semicircular canals) on the neural representation of gravity, 2) the resolution of gravitoinertial force into neural representations of gravity and linear acceleration, and 3) the neural representation of the dynamics of the semicircular canals. By combining these simple hypotheses within the internal model framework, the model mimics human responses to a number of different paradigms, ranging from simple paradigms, like roll tilt, to complex paradigms, like postrotational tilt and centrifugation. It is important to note that the exact same mechanisms can explain responses induced by simple movements as well as by more complex paradigms; no additional elements or hypotheses are needed to match the data obtained during more complex paradigms. Therefore these modeled response characteristics are consistent with available data and with the hypothesis that the nervous system uses internal models to estimate tilt and translation in the presence of ambiguous sensory cues.
Publication
Journal: Journal of Bacteriology
November/30/1996
Abstract
Barat, M. (Centre National de la Recherche Scientifique, Gif-sur-Yvette, Seine et Oise, France), C. Anagnostopoulos, and A.-M. Schneider. Linkage relationships of genes controlling isoleucine, valine, and leucine biosynthesis in Bacillus subtilis. J. Bacteriol.90:357-369. 1965.-In Bacillus subtilis, the genetic loci controlling isoleucine and valine biosynthesis are not all clustered. Some of them were located on two distinct transforming deoxyribonucleic acid "molecules." One of these molecules (the "ileilva(2-4)-met segment") carries the threonine deaminase and the dihydroxy acid dehydrase loci linked to methionine markers. The other (the "ilva(1-3)-leu segment") bears the reductoisomerase locus and one or more loci involved in leucine synthesis. A phenylalanine marker was also shown to be weakly linked to this latter group. In transduction mediated by phage PBS-1, these groups are transferred jointly with other gene clusters. The phage appears to convey chromosome fragments considerably longer than the transforming "molecules." The genetic maps of both the above segments were extended by transduction. Some groups previously studied by transformation can be placed in the following linear order: the ile-ilva(2-4)-met segment, the cluster of loci involved in aromatic amino acid synthesis (try segment), and a lysine locus. An arginine locus is cotransduced with the phe-ilva(1-2)-leu segment. Recombination frequencies between linked markers are much lower in transduction by this phage than in transformation.
Publication
Journal: Plant Physiology
December/14/2009
Abstract
Previously, the GRF-INTERACTING FACTOR1 (GIFGIFGIF gene family, GIFGIFgifgifgifGIFGIFGIFgifGIF gene family are functionally redundant. Kinematic analysis on leaf growth revealed that the gif triple mutant as well as other strong gif mutants developed leaf primordia with fewer cells, which was due to the low rate of cell proliferation, eventually resulting in earlier exit from the proliferative phase of organ growth. The low proliferative activity of primordial leaves was accompanied by decreased expression of cell cycle-regulating genes, indicating that GIF genes may act upstream of cell cycle regulators. Analysis of gif double and triple mutants clarified a previously undescribed role of the GIF gene family: gif mutants had small vegetative shoot apical meristems, which was correlated with the development of small leaf primordia. gif triple mutants also displayed defective structures of floral organs. Taken together, our results suggest that the GIF gene family plays important roles in the control of cell proliferation via cell cycle regulation and in other developmental properties that are associated with shoot apical meristem function.
Publication
Journal: Plant Journal
March/29/2015
Abstract
The growth-regulating factors (GRFs) are plant-specific transcription factors. They form complexes with GRF-interacting factors (GIFs), a small family of transcriptional co-activators. In Arabidopsis thaliana, seven out of the nine GRFs are controlled by microRNA miR396. Analysis of Arabidopsis plants carrying a GRF3 allele insensitive to miR396 revealed a strong boost in the number of cells in leaves, which was further enhanced synergistically by an additional increase of GIFGIFGIFGIFGIF network impinges on different stages of leaf development. Our results integrate the post-transcriptional control of the GRF transcription factors with the progression of leaf development.
Publication
Journal: British Journal of Cancer
November/2/1998
Abstract
Circulating neuron-specific enolase (NSE) and chromogranin A (CgA) were measured in 128 patients with neuroendocrine tumours (NET) to compare their sensitivity and specificity, to investigate factors associated with elevated serum levels and to determine the usefulness of these markers in the follow-up of NET patients. NSE (Cispack NSE, Cis Bio International, Gif-sur-Yvette, France; normal <12.5 microg l(-1)), and chromogranin A (CgA-Riact, Cis Bio International, normal <100 microg l(-1)) were measured in 128 patients without renal insufficiency. There were 99 patients with gastroenteropancreatic (GEP) NET, 19 with medullary thyroid carcinoma and ten with phaeochromocytoma. Fifty-three patients with non-NET were studied as controls. Serum NSE and CgA levels were elevated in 48 (38%) and 76 (59%) of the 128 NET patients respectively. In all groups of NET patients, CgA proved to be more sensitive than NSE. NSE and CgA had a specificity of 73% and 68% respectively. Immunostaining for NSE was positive in three out of eight controls with elevated CgA levels, whereas immunostaining for CgA and synaptophysin was negative in all cases. Elevated CgA levels were significantly associated with two independent parameters, namely the presence of other secretions (P = 0.0001) and a heavy tumour burden (P = 0.001). Elevated NSE levels were exclusively associated with poor tumour differentiation (P = 0.01). Among six patients with NET followed for 11-37 months, CgA appeared to be a better marker of tumour evolution than NSE. We suggest that CgA ought to be the only general marker screened in NET patients.
Publication
Journal: Circulation
December/6/1999
Abstract
BACKGROUND
Whether myocardial ATP content falls in heart failure is a long-standing and controversial issue. The mechanism(s) to explain any decrease in ATP content during heart failure have not been identified.
RESULTS
Cardiac dysfunction, heart failure, and a prolonged steady state of heart failure were induced by chronic right ventricular pacing for 1 to 2 weeks, 3 to 4 weeks, and 7 to 9 weeks in dogs. Cardiac function and myocardial O(2) consumption (Mf1.gif" BORDER="0">O(2)) were measured with the dogs in the conscious state. ATP, total purine, and creatine were measured in biopsy specimens obtained at each stage. ATP and the total purine pool progressively fell at rates of 0.12 and 0.15 nmol. mg protein(-1). d(-1), despite an increase in Mf1.gif" BORDER="0">O(2). The rate of loss of creatine was 1.06 nmol. mg protein(-1). d(-1), 7 times faster than the depletion of total purine.
CONCLUSIONS
(1) ATP contents progressively decreased during heart failure as a result of a loss of the total purine pool. The loss of purines may be due to inhibition of de novo purine synthesis. (2) Loss of creatine is an early marker of heart failure and may serve as a compensatory mechanism minimizing the reduction of the total purine pool in the failing heart.
Publication
Journal: Critical Care
May/18/2009
Abstract
BACKGROUND
There are no universally accepted diagnostic criteria for gastrointestinal failure in critically ill patients. In the present study we tested whether the occurrence of food intolerance (FI) and intra-abdominal hypertension (IAH), combined in a 5-grade scoring system for assessment of gastrointestinal function (the Gastrointestinal Failure [GIF] score), predicts mortality. The prognostic value of the GIF score alone and in combination with the Sequential Organ Failure Assessment (SOFA) score is evaluated, and the incidence and outcome of gastrointestinal failure is described relative to the GIF score.
METHODS
A total of 264 subsequently hospitalized patients, who were mechanically ventilated on admission and stayed in the intensive care unit (ICU) for longer than 24 hours, were prospectively studied. GIF score was documented daily as follows: 0 = normal gastrointestinal function; 1 = enteral feeding with under 50% of calculated needs or no feeding 3 days after abdominal surgery; 2 = FI or IAH; 3 = FI and IAH; and 4 = abdominal compartment syndrome (ACS). Admission parameters and mean GIF and SOFA scores for the first 3 days were used to predict ICU outcome.
RESULTS
FI developed in 58.3%, IAH in 27.3%, and both together in 22.7% of patients. The mean GIF score for the first 3 days in the ICU was identified as an independent risk factor for mortality (odds ratio = 3.02, 95% confidence interval = 1.63 to 5.59; P < 0.001). The GIF score integrated into the SOFA score allowed better prediction of ICU mortality than did the SOFA score alone, and was an independent predictor of mortality (odds ratio = 1.49, 95% confidence interval = 1.28 to 1.74; P < 0.001). The development of gastrointestinal failure (FI plus IAH) was associated with significantly higher ICU and 90-day mortality.
CONCLUSIONS
The GIF score is useful for classifying information on the gastrointestinal system. The mean GIF score during the first 3 days in the ICU had high prognostic value for ICU mortality. Development of gastrointestinal failure is associated with significantly impaired outcome.
Publication
Journal: Plant Physiology
October/21/2014
Abstract
The precise control of gene regulation, and hence, correct spatiotemporal tissue patterning, is crucial for plant development. Plant microRNAs can constrain the expression of their target genes at posttranscriptional levels. Recently, microRNA396 (miR396) has been characterized to regulate leaf development by mediating cleavage of its GROWTH-REGULATING FACTOR (GRF) targets. miR396 is also preferentially expressed in flowers. However, its function in flower development is unclear. In addition to narrow leaves, pistils with a single carpel were also observed in miR396 overexpression plants. The dramatically reduced expression levels of miR396 targets (GRF1, GRF2, GRF3, GRF4, GRF7, GRF8, and GRF9) caused pistil abnormalities, because the miR396-resistant version of GRF was able to rescue miR396-overexpressing plants. Both GRF and GRF-INTERACTING FACTOR (GIF) genes are highly expressed in developing pistils, and their expression patterns are negatively correlated with that of miR396. GRF interacted with GIF to form the GRF/GIF complex in plant cell nucleus. miR396 suppressed the expression of GRF genes, resulting in reduction of GRF/GIF complex. gif single mutant displayed normal pistils, whereas gif triple mutant gifgifgifGIF function as cotranscription factors, and both are required for pistil development. Our analyses reveal an important role for miR396 in controlling carpel number and pistil development via regulation of the GRF/GIF complex.
Publication
Journal: Journal of Neurophysiology
July/4/2001
Abstract
All linear accelerometers, including the otolith organs, respond equivalently to gravity and linear acceleration. To investigate how the nervous system resolves this ambiguity, we measured perceived roll tilt and reflexive eye movements in humans in the dark using two different centrifugation motion paradigms (fixed radius and variable radius) combined with two different subject orientations (facing-motion and back-to-motion). In the fixed radius trials, the radius at which the subject was seated was held constant while the rotation speed was changed to yield changes in the centrifugal force. In variable radius trials, the rotation speed was held constant while the radius was varied to yield a centrifugal force that nearly duplicated that measured during the fixed radius condition. The total gravito-inertial force (GIF) measured by the otolith organs was nearly identical in the two paradigms; the primary difference was the presence (fixed radius) or absence (variable radius) of yaw rotational cues. We found that the yaw rotational cues had a large statistically significant effect on the time course of perceived tilt, demonstrating that yaw rotational cues contribute substantially to the neural processing of roll tilt. We also found that the orientation of the subject relative to the centripetal acceleration had a dramatic influence on the eye movements measured during fixed radius centrifugation. Specifically, the horizontal vestibuloocular reflex (VOR) measured in our human subjects was always greater when the subject faced the direction of motion than when the subjects had their backs toward the motion during fixed radius rotation. This difference was consistent with the presence of a horizontal translational VOR response induced by the centripetal acceleration. Most importantly, by comparing the perceptual tilt responses to the eye movement responses, we found that the translational VOR component decayed as the subjective tilt indication aligned with the tilt of the GIF. This was true for both the fixed radius and variable radius conditions even though the time course of the responses was significantly different for these two conditions. These findings are consistent with the hypothesis that the nervous system resolves the ambiguous measurements of GIF into neural estimates of gravity and linear acceleration. More generally, these findings are consistent with the hypothesis that the nervous system uses internal models to process and interpret sensory motor cues.
Publication
Journal: Plastic and Reconstructive Surgery
October/18/2007
Abstract
BACKGROUND
Many of the anatomical changes of facial aging are still poorly understood. This study looked at the aging process in individuals linearly over time, focusing on aspects of periorbital aging and the upper midface.
METHODS
The author compared photographs of patients' friends and relatives taken 10 to 50 years before with closely matched recent follow-up pictures. The best-matching old and recent pictures were equally sized and superimposed in the computer. The images were then assembled into GIF animations, which automate the fading of one image into the other and back again indefinitely.
RESULTS
The following findings were new to the author: (1) the border of the pigmented lid skin and thicker cheek skin (the lid-cheek junction) is remarkably stable in position over time, becoming more visible by contrast, not by vertical descent as is commonly assumed. (2) Orbicularis wrinkles on the cheek and moles and other markers on the upper midface were also stable over decades. (3) With aging, there can be a distinct change in the shape of the upper eyelid. The young upper lid frequently has a medially biased peak. The upper lid peak becomes more central in the older lid. This article addresses these three issues. No evidence was seen here for descent of the globe in the orbit.
CONCLUSIONS
There seems to be very little ptosis (inferior descent) of the lid-cheek junction or of the upper midface. These findings suggest that vertical descent of skin, and by association, subcutaneous tissue, is not necessarily a major component of aging in those areas. In addition, the arc of the upper lid changes shape in a characteristic way in some patients. Other known changes of the periorbital area are visualized.
Publication
Journal: Experimental Brain Research
February/11/1996
Abstract
Model simulations of the squirrel monkey vestibulo-ocular reflex (VOR) are presented for two motion paradigms: constant velocity eccentric rotation and roll tilt about a naso-occipital axis. The model represents the implementation of three hypotheses: the "internal model" hypothesis, the "gravito-inertial force (GIF) resolution" hypothesis, and the "compensatory VOR" hypothesis. The internal model hypothesis is based on the idea that the nervous system knows the dynamics of the sensory systems and implements this knowledge as an internal dynamic model. The GIF resolution hypothesis is based on the idea that the nervous system knows that gravity minus linear acceleration equals GIF and implements this knowledge by resolving the otolith measurement of GIF into central estimates of gravity and linear acceleration, such that the central estimate of gravity minus the central estimate of acceleration equals the otolith measurement of GIF. The compensatory VOR hypothesis is based on the idea that the VOR compensates for the central estimates of angular velocity and linear velocity, which sum in a near-linear manner. During constant velocity eccentric rotation, the model correctly predicts that: (1) the peak horizontal response is greater while "facing-motion" than with "back-to-motion"; (2) the axis of eye rotation shifts toward alignment with GIF; and (3) a continuous vertical response, slow phase downward, exists prior to deceleration. The model also correctly predicts that a torsional response during the roll rotation is the only velocity response observed during roll rotations about a naso-occipital axis. The success of this model in predicting the observed experimental responses suggests that the model captures the essence of the complex sensory interactions engendered by eccentric rotation and roll tilt.
Publication
Journal: American Journal of Transplantation
August/7/2005
Abstract
Kidney allograft failure is most often caused by chronic allograft nephropathy, a process of interstitial fibrosis (GIF) and tubular atrophy (TA). We assessed the pathology of living donor (LD) grafts compared to deceased donor (DD). Included are 321 recipients (245 LD; 76 DD) with protocol biopsies the first 2 years of transplant. In LD, GIF was present in 7%, 31%, 61% and 71% of grafts at 0, 4, 12 and 24 months. TA progressed in parallel to GIF. Compared to LD, more DD grafts had GIF at time 0 (29%, p = 0.002); thereafter the incidence of GIF was similar. In LD, GIF was associated with lower glomerular filtration rate (GFR)(1 year) (no GIF, 62 +/- 16; GIF, 49 +/- 15 mL/min/m(2) iothalamate clearance, p = 0.001) and reduced graft survival (HR = 2.2, p = 0.009). GIF in LD related to acute rejection (HR = 2.6, p = 0.01), polyoma nephropathy (OR = 4.4, p = 0.02) and lower levels of GFR 3 weeks post-transplant (HR = 0.961; p = 0.03, multivariate). However, GIF also developed in 53% of recipients lacking these covariates. Thus, GIF/TA develops in the majority of LD grafts, it is often mild but is associated with reduced function and survival. GIF frequently develops in the absence of risk factors. Lower GFR post-transplant identify patients at highest risk of GIF.
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