Wei Chen
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Publication
Journal: Australasian physical & engineering sciences in medicine
October/16/2019
Abstract
There has been few studies focusing on the disc pressure of the upper thoracic spine and it still lacks the quantitative pressure measurement of each spinal disc segment. The aim of this study was to study the pressure changes of intervertebral disc in porcine upper thoracic spine using pressure-sensitive film. Twelve porcine thoracic motion segments were harvested and successively loaded with vertical loads of 100 N, 150 N, and 200 N during 5° of anterior flexion, 5° of posterior extension and 5° of lateral bending. The resulting pressure values were measured. During anterior flexion, the anterior annulus of all segments at all loads showed higher mean pressure values than those during vertical compression, whereas the posterior annulus did not show higher mean values. During posterior extension, the anterior annulus of all segments showed lower mean pressure values than those during vertical compression, whereas the posterior annulus did not show lower mean pressure values. During lateral bending, the annulus of all segments showed higher mean pressure values than those during vertical compression. The posterior thoracic vertebra plays an important role in the motion of the upper thoracic vertebral segment and pressure distribution. During lateral bending, the concave side pressure of the annulus increases obviously, suggesting that asymmetrical force is a contributory factor for scoliosis progression.
Publication
Journal: Biochemical and biophysical research communications
October/8/2019
Abstract
The triple-negative breast cancer (TNBC) subtype is the most aggressive form of invasive breast cancer. Although autophagy is critical to the progression of TNBC, the mechanism of autophagy in regulating the metastatic potential of TNBC still remains unclear. Recently, the effector of the Hippo signaling pathway yes-associated protein (YAP) was shown to promote autophagy. To investigate autophagy regulation in YAP signaling in the context of cancer metastasis, we performed profiling analysis of YAP signaling, YAP subcellular localization, autophagosome formation and cell invasiveness in TNBC cell lines (MDA-MB-231 and Hs 578T) versus estrogen receptor (ER) positive breast cancer cell line MCF7. Our results showed that YAP transcriptional and protein expression was significantly upregulated in TNBC. When we triggered autophagy response in TNBC, YAP translocated into the nucleus and the expression of YAP target gene ankyrin repeat domain 1 (ANKRD1) increased remarkably. The correlation between autophagy response and YAP expression in TNBC was confirmed at the single-cell level. Furthermore, the inhibition of YAP nuclear entry greatly impeded the migration and invasion of TNBC cells while it did not affect the mobility of ER positive breast cancer cells. Therefore, this research established the autophagy-YAP-metastasis axis in TNBC and sheds light on the application of targeting YAP for TNBC therapeutics.
Publication
Journal: Journal of investigative surgery : the official journal of the Academy of Surgical Research
October/7/2019
Abstract
Purpose: The purpose of this study was to present a new absorbable spacer for medial compartmental knee osteoarthritis (OA). The functional and radiographic results of patients treated with the novel surgical technique were also evaluated to investigate its clinical feasibility. Methods: Patients with medial compartmental knee OA who underwent open-wedge high tibial osteotomy (HTO) with absorbable β-TCP/PLGA [30% beta-tricalcium phosphate and 70% poly (lactic-co-glycolic acid)] spacer implantation and proximal fibular osteotomy from January 2016 to February 2017 were retrospectively analyzed. The operation time, blood loss, and relevant complications were reviewed. The femorotibial angle (FTA), varus angle (VA), joint line convergence angle (JLCA), American Knee Society Score (KSS), and visual analog scale (VAS) score were recorded preoperatively and at the final follow-up, respectively. Results: At the final follow-up, the mean FTA and JLCA were 179.85° ± 4.34° and 2.44° ± 1.26°, respectively, which were smaller than the preoperative values (182.94° ± 3.86° and 4.12° ± 1.65°, respectively; both p < 0.001). The final VA and VAS score were lower than those measured preoperatively (both p < 0.001). The clinical and functional KSSs at the final follow-up were higher than the preoperative scores (p < 0.001). Conclusions: This novel absorbable spacer could provide adequate stability for the tibial osteotomy gap, at a lower cost than a traditional plate. With the use of this spacer as an osteoinductive and biodegradable device, secondary surgery for fixation removal could be avoided. The novel surgical technique could improve both the radiographic appearance and the function of the knee in patients with knee OA.
Publication
Journal: World neurosurgery
September/24/2019
Publication
Journal: The American journal of managed care
September/13/2019
Abstract
The Veterans Affairs (VA) Geriatric Scholars Program (GSP) is a workforce development program to enhance skills and competencies among VA clinicians who provide healthcare for older veterans in VA primary care clinics. An intensive geriatrics didactics (IGD) course is a core element of this professional development program. The objective of this study was to evaluate the impact of completing the IGD course on providers' rates of prescribing definite potentially inappropriate medications (DPIMs) based on Beers Criteria from 2008 to 2016.We applied a longitudinal interrupted time series design to examine changes in DPIM prescribing rates for GSP participants before and after completing the IGD course.The time series was divided into two 12-month periods, representing the preintervention period (ie, 12 months prior to completing the IGD course) and the postintervention period (ie, 12 months after completing the IGD course), and populated with pharmacy dispensing data from the VA's Corporate Data Warehouse. An adjusted slope impact model was developed to estimate the postintervention change in the proportion of the dispensed medications identified as DPIMs.After adjusting for case mix, we observed a statistically significant reduction in the proportion of DPIMs dispensed post IGD (slope change, 0.994; 95% CI, 0.991-0.997). This change in slope reflects a total decrease of 7971 DPIM dispensings during the postintervention period. This equates to an estimated 24 fewer DPIM dispensings per provider during the postintervention period.Although the size of the effect was modest, we found that participation in the GSP IGD course reduced prescribing of DPIMs for older veterans.
Publication
Journal: Journal of medical entomology
September/10/2019
Abstract
Sarcophaga peregrina is an important flesh fly species for estimating the minimum postmortem interval (PMImin) in forensic entomology. The accurate determination of the developmental age is a crucial task for using necrophagous sarcophagids to estimate PMImin. During larval development, the age determination is straight forward by the morphological changes and variation of length, weight, and width; however, the age estimation of sarcophagid intrapuparial is more difficult due to anatomical and morphological changes not being visible. The analysis of differentially expressed genes (DEGs) during sarcophagid metamorphosis is a potential method for age estimation of intrapuparial. In the present study, real-time quantitative polymerase chain reaction (RT-qPCR) was used to analyze the differential gene expression level of S. peregrina intrapuparial in different constant temperatures (35°C, 25°C, and 15°C). In addition, the appropriate reference genes of S. peregrina were selected in the intrapuparial and at different temperatures to obtain reliable and valid gene expression profiles. The results indicated that two candidate genes (18S rRNA and 28S rRNA) were the most reliable reference genes, and four DEGs (Hsp90, A-alpha, AFP, AFBP) have the potential to be used to more accuracy estimate the age of S. peregrina intrapuparial.
Publication
Journal: Asian-Australasian journal of animal sciences
September/3/2019
Abstract
The objective of this study was to measure the special expression pattern of lipid metabolism genes and investigate the molecular mechanisms underlying intramuscular fat (IMF) deposition in Longissimus dorsi muscle of Laiwu pigs.Thirty-six pigs (Laiwu n =18; Duroc×Landrace×Yorkshire n = 18) were used for the measurement of the backfat thickness, marbling score, IMF content, and expression of lipid metabolism genes.Significant correlations were found between IMF content and the mRNA expression of lipid metabolism genes. Of the 14 fat deposition genes measured, FASN showed the strongest correlation (r = 0.75, p=0.001) with IMF content, and of the 6 fat removal genes, CPT1B exhibited the greatest negative correlation (r = -0.66, p=0.003) with IMF content in Laiwu pig. Multiple regression analysis showed that CPT1B, FASN, SLC27A1, and FABP3 contributed 38% of the prediction value for IMF content in Laiwu pigs. Of these four variables, CPT1B had the greatest contribution to IMF content (14%) followed by FASN (11%), SLC27A1 (9%) and FABP3 (4%).Our results indicate that the combined effects of an upregulation in fat deposition genes and downregulation in fat removal genes promotes IMF deposition in Laiwu pigs.
Publication
Journal: Journal of biotechnology
February/15/2019
Abstract
Seamless modification of the Escherichia coli genome using positive selection / negative selection is widely used in metabolic engineering and functional genome analysis. Some excellent negative selection systems have been reported, of which tetA-sacB and inducible toxins system are prominent. To expand the existing negative selection toolkit, we constructed a new negative selection marker system based on kil gene of lambda prophage. The selection stringency of kil was measured and compared with the most widely used counter-selection gene, sacB, at the lacI, ack, and dbpa loci using different E. coli strains. At all these loci of tested strains, the selection stringency of kil significantly exceeds that of sacB by 2- to 28-fold. When dsDNA fragments were employed for recombination, the efficiency for isolating the correct recombinant of kil was significantly higher than that of sacB. This new negative selection system does not require special media or extended incubation time. However, our system cannot be used in host strains containing temperature-sensitive kil gene. A Red system providing plasmid without kil gene is recommended for use together with our system. Our counter-selection system is expected to be an addition to the engineering arsenal of E. coli.
Publication
Journal: Journal of chemical theory and computation
February/15/2019
Abstract
Building upon the OPLS3 force field we report on an enhanced model, OPLS3e, that further extends its coverage of medicinally relevant chemical space by addressing limitations in chemotype transferability. OPLS3e accomplishes this by incorporating new parameter types that recognize moieties with greater chemical specificity and integrating an on-the-fly parametrization approach to the assignment of partial charges. As a consequence, OPLS3e leads to greater accuracy against performance benchmarks that assess small molecule conformational propensities, solvation, and protein-ligand binding.
Publication
Journal: ISA transactions
January/28/2019
Abstract
With the arrival of big data era, the integration of Case-Based Reasoning (CBR) and Bayesian Network (BN) has become increasingly a promising technology in implementing the intelligence of engineering application. To further improve the efficiency of the integrated system and make it adapt to the large number of parameter under big data, Within-Cross (WC) algorithm is proposed in this paper to assigned big data to each slave node of Hadoop platform for parallel data processing. The WC algorithm can greatly reduce the time costing of parallel data processing and thus improve the efficiency of the integrated system by fully using the computation resource of Hadoop platform. To further enhance the accuracy of the integrated system, this paper proposes a new method called Weighted Super Parameters of Dirichlet Distribution (WSPDD) algorithm to perform probability learning. The WSPDD algorithm gives a weight to each super parameter of Dirichlet Distribution of all problem parameters to adjust the result of probability statistics and then improve probability learning. Therefore, the accuracy of the integrated system is greatly improved. Finally, an application domain is taken as a case study to validate the proposed method.
Publication
Journal: Bioinformatics (Oxford, England)
December/6/2018
Abstract
UNASSIGNED
Integrative analysis of multi-omics data from different high-throughput experimental platforms provides valuable insight into regulatory mechanisms associated with complex diseases, and gains statistical power to detect markers that are otherwise overlooked by single-platform omics analysis. In practice, a significant portion of samples may not be measured completely due to insufficient tissues or restricted budget (e.g. gene expression profile are measured but not methylation). Current multi-omics integrative methods require complete data. A common practice is to ignore samples with any missing platform and perform complete case analysis, which leads to substantial loss of statistical power.
UNASSIGNED
In this article, inspired by the popular Integrative Bayesian Analysis of Genomics data (iBAG), we propose a full Bayesian model that allows incorporation of samples with missing omics data.
UNASSIGNED
Simulation results show improvement of the new full Bayesian approach in terms of outcome prediction accuracy and feature selection performance when sample size is limited and proportion of missingness is large. When sample size is large or the proportion of missingness is low, incorporating samples with missingness may introduce extra inference uncertainty and generate worse prediction and feature selection performance. To determine whether and how to incorporate samples with missingness, we propose a self-learning cross-validation (CV) decision scheme. Simulations and a real application on child asthma dataset demonstrate superior performance of the CV decision scheme when various types of missing mechanisms are evaluated.
UNASSIGNED
Freely available on the GitHub at https://github.com/CHPGenetics/FBM.
UNASSIGNED
Supplementary data are available at Bioinformatics online.
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Publication
Journal: Microbial pathogenesis
December/2/2018
Abstract
The present study was aimed to investigate and understand the mechanism of inhibitory effect of phenyl benzoxime on proliferation of SNU-306 cells. Proliferation of SNU-306 cells transfected with wild-type p53-induced phosphatase 1 (Wip1)-siRNA or treated with phenyl benzoxime was examined by 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Induction of apoptosis was examined by flow cytometry using annexin V-fluorescein isothiocyanate/propidium iodide staining. In SNU-306 cells Wip1 mRNA and protein expression was found to be significantly (p < 0.05) higher compared to normal cells. However, Wip1-siRNA transfection significantly (p < 0.02) inhibited the expression of Wip1 at 60 nmol/l. The proliferation of SNU-306 cells was inhibited to 3.7% on transfection with Wip1-siRNA. Phenyl benzoxime reduced proliferation to 92.0, 75.0, 49.0, 19.0 and 4.0% at 1, 2, 4, 8 and 10 μM doses, respectively. The expression of Wip1 was significantly (p < 0.01) suppressed in SNU-306 cells on phenyl benzoxime treatment. Phenyl benzoxime induced apoptosis in 74.73% cells at 10 μM doses compared to 1.34% in control. Treatment with phenyl benzoxime markedly increased the expression of Bax, caspase-3 and p53 and decreased Bcl-2 mRNA. Moreover, addition of SB203580 to cultures of SNU-306 cells significantly (p < 0.01) prevented phenyl benzoxime mediated inhibition of cell proliferation. Phenyl benzoxime induces apoptosis and inhibits SNU-306 cell proliferation by silencing Wip1 expression through p38 MAPK signaling pathway activation. Therefore, phenyl benzoxime can act as an important chemotherapeutic agent for breast cancer treatment.
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Publication
Journal: Journal of chemical information and modeling
November/27/2018
Abstract
The CRISPR-Cas9 system derived from adaptive immunity in bacteria and archaea has been developed into a powerful tool for genome engineering with wide-ranging applications. Optimizing single guide RNA (sgRNA) design to improve efficiency of target cleavage is a key step for successful gene editing using the CRISPR-Cas9 system. Because not all sgRNAs that cognate to a given target gene are equally effective, computational tools have been developed based on experimental data to increase the likelihood of selecting effective sgRNAs. Despite considerable efforts to date, it still remains a big challenge to accurately predict functional sgRNAs directly from large-scale sequence data. We propose DeepCas9, a deep-learning framework based on convolutional neural network (CNN), to automatically learn the sequence determinants and further enable the identification of functional sgRNAs for the CRISPR-Cas9 system. We show that the CNN method outperforms previous methods in both, the ability to correctly identify highly active sgRNAs in experiments not used in the training and the ability to accurately predict the target efficacies of sgRNAs in different organisms. Besides, we further visualize the convolutional kernels and show the match of identified sequence signatures and known nucleotide preferences. We finally demonstrate the application of our method for the design of next-generation genome-scale CRISPRi and CRISPRa libraries targeting human and mouse genomes. We expect that DeepCas9 will assist in reducing the numbers of sgRNAs that need to be experimentally validated to enable more effective and efficient genetic screens and genome engineering. DeepCas9 can be freely accessed at https://github.com/lje00006/DeepCas9.
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Publication
Journal: Optics express
November/25/2018
Abstract
Quantum key distribution (QKD) offers information-theoretic security verified by quantum mechanics to share keys between legitimate users. Most of the existing QKD systems employ active decoy states based on weak coherent sources (WCS). Meanwhile, parametric down-conversion (PDC) sources are seldom used due to several of their shortcomings. In the present work, to show the superiority of PDC sources, we have accomplished a proof-of-principle demonstration of a PDC source-based QKD with over 40 dB based on the one-way BB84 protocol. In this QKD system, a novel passive decoy-state scheme-secure to coherent attacks-is proposed, using several built-in decoy states for parameter estimation. This not only avoids intensity modulating errors, but also diminishes all possible information leakage from the intensity modulating process. The experimental results show a significantly enhanced performance compared with existing PDC source-based QKD systems. In addition, it exhibits some superiority even over active decoy-state QKD systems based on WCS.
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Publication
Journal: Optics express
November/25/2018
Abstract
Compressing picosecond laser pulses to the femtosecond level is an attractive shortcut for obtaining femtosecond laser pulses. However, dechirped pulses generated by nonlinear compression with self-phase modulation (SPM) show obvious pedestals, which are induced by nonlinear chirp accumulation in spectral broadening process and cannot be easily suppressed. Here, we report systematic numerical simulations and experimental studies on self-similar amplification of picosecond pulses in a short gain fiber for obtaining ~100-fs laser pulses with nearly transform-limited (TL) temporal quality. It is demonstrated that self-similar amplification with picosecond seed pulses is only sensitive to pulse duration and pulse energy. Based on this optimization guideline, we built a compact self-similar amplification fiber system with a picosecond fiber laser as the seed source. This system outputs 66-fs pulses with 6.1-W average power at a repetition rate of 30 MHz. Due to the linear chirp produced in self-similar evolution process, compressed pulses show nearly TL temporal quality. It promises an efficient way of obtaining high-quality femtosecond laser pulses from a picosecond laser source.
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Publication
Journal: Advanced materials (Deerfield Beach, Fla.)
November/18/2018
Abstract
Black phosphorus (BP), first synthesized in 1914 and rediscovered as a new member of the family of 2D materials in 2014, combines many extraordinary properties of graphene and transition-metal dichalcogenides, such as high charge-carrier mobility, and a tunable direct bandgap. In addition, it displays other distinguishing properties, e.g., ambipolar transport and highly anisotropic properties. The successful application of BP in electronic and optoelectronic devices has stimulated significant research interest in other allotropes and alloys of 2D phosphorene, a class of 2D materials consisting of elemental phosphorus. As an atomically thin sheet, the various interfaces presented in 2D phosphorene (substrate/phosphorene, electrode/phosphorene, dielectric/phosphorene, atmosphere/phosphorene) play dominant roles in its bottom-up synthesis, and determine several key characteristics for the devices, such as carrier injection, carrier transport, carrier concentration, and device stability. The rational design/engineering of interfaces provides an effective way to manipulate the growth of 2D phosphorene, and modulate its electronic and optoelectronic properties to realize high-performance multifunctional devices. Here, recent progress of the interface engineering of 2D phosphorene is highlighted, including the epitaxial growth of single-layer blue phosphorus on different substrates, surface functionalization of BP for high-performance complementary devices, and the investigation of the BP degradation mechanism in ambient air.
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Publication
Journal: Journal of diabetes investigation
November/13/2018
Abstract
UNASSIGNED
Previous studies have shown that glucose peak time during the oral glucose tolerance test varies in type 2 diabetes patients; however, characteristics of this heterogeneity remain unclear. This research aimed to investigate the characteristics of delayed glucose peak time in type 2 diabetes.
METHODS
A total of 178 participants who underwent the oral glucose tolerance test were divided into five groups according to glucose peak time.
RESULTS
A total of 25 participants with normal glucose tolerance had a glucose peak at 30 min. Among participants with type 2 diabetes, 28 had a glucose peak at 60 min, 48 at 90 min, 45 at 120 min and 32 at 150 min. With the glucose peak time delayed, glycated hemoglobin, area under the glucose curve and homeostatic model assessment of insulin resistance increased gradually (P = 0.038, P < 0.0001, P < 0.0001, respectively), and oral glucose insulin sensitivity, homeostatic model assessment of β-cell function, insulinogenic index, modified β-cell function index and disposition indices decreased (P < 0.0001 for all). On multinominal logistic regression, insulinogenic index (odds ratio 0.73, 95% confidence interval 0.57-0.93, P = 0.01), modified β-cell function index (odds ratio 0.67, 95% confidence interval 0.47-0.94, P = 0.023) and oral glucose insulin sensitivity (odds ratio 0.91, 95% confidence interval 0.87-0.96, P < 0.0001) were independently correlated with delayed glucose peak time.
CONCLUSIONS
Delay in glucose peak time indicated an increase in blood glucose and a decrease in insulin sensitivity and secretion. Furthermore, insulinogenic index, modified β-cell function index and oral glucose insulin sensitivity contributed to delayed glucose peak time.
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Publication
Journal: Molecular therapy. Nucleic acids
November/13/2018
Abstract
RNA modifications are additions of chemical groups to nucleotides or their local structural changes. Knowledge about the occurrence sites of these modifications is essential for in-depth understanding of the biological functions and mechanisms and for treating some genomic diseases as well. With the avalanche of RNA sequences generated in the post-genomic age, many computational methods have been proposed for identifying various types of RNA modifications one by one. However, so far no method whatsoever has been developed for simultaneously identifying several different types of RNA modifications. To address such a challenge, we developed a predictor called "iRNA-3typeA," by which we can simultaneously identify the occurrence sites of the following three most frequently observed modifications in RNA: (1) N1-methyladenosine (m1A), (2) N6-methyladenosine (m6A), and (3) adenosine to inosine (A-to-I). It has been shown via rigorous cross-validations for the RNA sequences from Homo sapiens and Mus musculus transcriptomes that the success rates achieved by the powerful new predictor are quite high. For the convenience of broad experimental scientists, a user-friendly web server for iRNA-3typeA has been established at http://lin-group.cn/server/iRNA-3typeA/. It is anticipated that iRNA-3typeA may become a useful high throughput tool for genome analysis.
Publication
Journal: Oncotarget
November/13/2018
Abstract
With dismal survival rate pancreatic cancer remains one of the most aggressive and devastating malignancy. Predominantly, due to the absence of a dependable methodology for early identification and limited therapeutic options for advanced disease. However, it takes over 17 years to develop pancreatic cancer from initiation of mutation to metastatic cancer; therefore, if diagnosed early; it may increase overall survival dramatically, thus, providing a window of opportunity for early detection. Recently, genomic expression analysis defined 4 subtypes of pancreatic cancer based on mutated genes. Hence, we need simple and standard, minimally invasive test that can monitor those altered genes or their associated pathways in time for the success of precision medicine, and liquid biopsy seems to be one answer to all these questions. Again, liquid biopsy has an ability to pair with genomic tests. Additionally, liquid biopsy based development of circulating tumor cells derived xenografts, 3D organoids system, real-time monitoring of genetic mutations by circulating tumor DNA and exosome as the targeted drug delivery vehicle holds lots of potential for the treatment and cure of pancreatic cancer. At present, diagnosis of pancreatic cancer is frantically done on the premise of CA19-9 and radiological features only, which doesn't give a picture of genetic mutations and epigenetic alteration involved. In this manner, the current diagnostic paradigm for pancreatic cancer diagnosis experiences low diagnostic accuracy. This review article discusses the current state of liquid biopsy in pancreatic cancer as diagnostic and therapeutic tools and future perspectives of research in the light of circulating tumor cells, circulating tumor DNA and exosomes.
Publication
Journal: OncoTargets and therapy
November/13/2018
Abstract
UNASSIGNED
Cancer-associated fibroblasts (CAFs) are a heterogeneous population, and different subpopulations play differential roles in tumor microenvironment. However, the prognostic role of podoplanin-positive CAFs in human lung cancer still remains controversial.
UNASSIGNED
Herein, we performed a meta-analysis including 12 published studies with 1,802 patients identified from PubMed and EBSCO to assess the prognostic impact of podoplanin-positive CAFs in lung cancer patients.
UNASSIGNED
We found that podoplanin+ fibroblast infiltration significantly decreased overall survival (OS), disease-free survival (DFS), and progression-free survival in patients. In stratified analyses, podoplanin+ fibroblast infiltration was significantly associated with worse OS and DFS in both squamous cell carcinoma and adenocarcinoma of lung. In addition, high density of podoplanin-positive CAFs significantly correlated with unfavorable clinicopathological features such as lymph node metastasis, and lymphatic, vascular, and pleural invasion of patients.
UNASSIGNED
Podoplanin+ fibroblast infiltration leads to worse clinical outcome in lung cancer patients, implicating that it is a valuable prognostic biomarker and targeting it may have a potential for effective treatment.
Publication
Journal: Methods in molecular biology (Clifton, N.J.)
November/10/2018
Abstract
To develop a commercial trait product, a large number of transgenic events are often produced to obtain the event with desired level of expression. It is crucial to develop efficient and sensitive molecular characterization methods to advance events with stable transgene expression, free of vector backbone sequences and without major changes to the native genome caused by transgene insertion. Here, we discuss a variety of analytical tools, including quantitative PCR (qPCR), Southern blot analysis, and various sequencing technologies, which have been widely used to determine the insert copy number, presence/absence of vector backbone sequences, integrity of the T-DNA, and genomic location of the T-DNA insertion. Moreover, since the discovery of RNA interference in 1998 (Fire et al., Nature 391:806-811, 1998), RNAi has emerged as another powerful tool in in the development of a new transgenic trait for insect control. RNAi creates a double-stranded RNA duplex as the active molecule which forms a strong secondary structure, resulting in challenges for detection. In addition to molecular analysis at the DNA level, this chapter describes detection methods of the active molecules (i.e., double-stranded RNA) for RNAi-based traits.
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Journal: Anatomical record (Hoboken, N.J. : 2007)
November/8/2018
Abstract
The anatomy of the posterolateral complex (PLC) of the knee is usually studied by dissection and magnetic resonance (MR) imaging, which is still controversial. We aim to study it based on the images and an interactive 3D-PDF from the Chinese Visible Human (CVH) datasets. CVH datasets (six transverse and one coronal) of the PLC and its adjacent structures were segmented and three-dimensionally reconstructed. Histological sections images were used to establish criteria for the segmentation. MR images were studied in comparison with CVH images. The PLC was mainly composed of the fibular collateral ligament (FCL), popliteofibular ligament (PFL), arcuate popliteal ligament (APL), popliteus tendon (PT), fabellofibular ligament (FFL) and biceps femoris tendon (BT). These structures had origins or insertions located close to each other and collectively maintained the stability of the PLC. The origins of the PT and the FCL were located on the lateral condyle of the femur. The APL was "Y" shaped and had a 100% occurrence in our study. Its lateral and medial heads originated, respectively, from the posterolateral part and medial-inferior part of fibrous capsule close to the lateral femoral condyle. The FCL, BT, main trunk of the APL, PFL and FFL had adjacent insertions on the posterolateral fibular head. CVH high-resolution sectional anatomical images and a 3D-pdf provided detailed morphological data for the PLC, and improved the identification and diagnostic accuracy for the PLC in MRI. We speculate that APL has a strong biological and mechanistic significance in the PLC. Anat Rec, 301:1764-1773, 2018. © 2018 Wiley Periodicals, Inc.
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Journal: Ying yong sheng tai xue bao = The journal of applied ecology
November/8/2018
Abstract
Soil phosphorus (P) deficiency is one of the main factors that diminish the yield of crops on the Loess Plateau. Fagopyrum tataricum is a dominant cereal plant on the Loess Plateau, whose responses to low-P stress are significantly different and dependent on its genotypes. Therefore, screening genotypes with efficient P utilization is an important approach to increase the yield of F. tataricum and promote the sustainable development of local agriculture. With fourteen F. tataricum genotypes, the agronomic traits, physiology and biochemical characters of F. tataricum at seedling stage under normal (2 mmol·L-1) and low-P treatment (0.2 mmol·L-1) were studied by using sand culture. By examining the characters of selected F. tataricum at seedling stage, the varieties of F. tataricum with low-P tolerance were screened out and their evaluation indices were assessed to provide theoretical basis for the breeding of F. tataricum with high P-efficiency and the infertile soil cultivation on the Loess Plateau. The results showed that under low-P stress, the shoots of all genotypes were more affected than roots, with the decline of shoot aboveground index, average root diameter, root surface area and root volume, whereas the length of main root was elongated. Root activity and soluble protein content were decreased. In contrast, other physiological and biochemical indicators were increased. Moreover, plant total phosphorus content and plant phosphorus accumulation reduced, but phosphorus use efficiency increased. The principal component analysis divided the 22 individual indicators into four mutually independent comprehensive indicators (cumulative contribution rate of 90.1%). Cluster analysis divided 14 kinds of F. tataricum into three categories: Low phosphorus tolerant, intermediate and phosphorus sensitive. In order to investigate the index of low-P tolerance of F. tataricum at seedling stage, the optimal regression equation was established with the comprehensive evaluation value of low-P tolerance (D value) as the dependent variable and the low-P tolerance index of each indicator as the independent variables. Seven indicators of root surface area, root length, plant height, aboveground dry mass, acid phosphatase, phosphorus accumulation and POD activity were examined, which could be used for the rapid identification of low-P tolerance of F. tataricum at seedling stage.
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Journal: The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians
November/4/2018
Abstract
Amniotic fluid embolism (AFE) and spontaneous hepatic rupture both are extremely rare complications of pregnancy that can be fatal to mother and/or child. AFE is characterized by a sudden collapse of the cardiovascular system, a change in mental status, and disseminated intravascular coagulation (DIC), occurring immediately during labor, delivery, or postpartum, caused by the inflow of amniotic components into the maternal circulation. Spontaneous hepatic rupture during pregnancy which is most often occurs alongside hypertensive disorders, eclampsia, or HELLP syndrome. We report on the case of a 28-year-old woman (G3P2) who is suffering from AFE and spontaneous hepatic rupture, without history of hypertensive disorders, preeclampsia/eclampsia, or HELLP syndrome, and she died suddenly after delivering of a severe asphyxial neonate within 1 h with postpartum of hepatic rupture and massive hemorrhage. The lack of typical clinical signs and symptoms resulted to the difficulty of early diagnosis. If AFE and hepatic rupture is highly suspected in a pregnant patient, a collaborative multidisciplinary approach is mandatory. Pregnancy women is simultaneously complicated in amniotic fluid embolism and spontaneous hepatic rupture, similar cases are infrequent in the literature, which is reviewed in this report, explore the pathophysiological changes, we hope that can be helpful for the prevention, diagnosis and treatment of similar cases.
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