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Publication
Journal: Journal of Comparative Neurology
January/17/2006
Abstract
In females of the blow fly Protophormia terraenovae, neurons with cell bodies in the pars lateralis (PL) projecting to the retrocerebral complex (designated as PL neurons) are necessary for the induction of reproductive diapause under short-day and low-temperature conditions. In the present study, neural connections between PL neurons and pigment-dispersing factor (PDF)-immunoreactive neurons were examined via immunolight microscopy and immunoelectron microscopy combined with backfills through the cardiac-recurrent nerve. Immunolight microscopy showed that fibers of PL neurons overlapped with PDF-immunoreactive fibers in the dorsolateral region of the superior protocerebral neuropil. Immunoelectron microscopy showed that PDF-immunoreactive fibers formed output synapses with fibers of PL neurons and unlabeled neurons in a region dorsoanteriorly located with respect to the calyx of the mushroom body. The distribution of synaptic connections between PDF-immunoreactive fibers and the fibers of PL neurons was sparse. According to the projection patterns, PDF-immunoreactive fibers with synaptic connections with PL neurons appeared to originate from PDF-immunoreactive neurons with cell bodies at the base of the medulla of the optic lobe (medulla PDF neurons), which are putative circadian clock neurons in P. terraenovae. PDF immunoreactivity was restrictively detected in dense-core vesicles but not in clear synaptic vesicles. The present results suggest that medulla PDF neurons convey time or photoperiodic information to PL neurons for diapause induction through direct synaptic connections.
Publication
Journal: BioMed Research International
December/12/2016
Abstract
BACKGROUND
In order to understand the colocalization of genetic loci amongst species, synteny and collinearity analysis is a frequent task in comparative genomics research. However many analysis software packages are not effective in visualizing results. Problems include lack of graphic visualization, simple representation, or inextensible format of outputs. Moreover, higher throughput sequencing technology requires higher resolution image output.
METHODS
To fill this gap, this paper publishes VGSC, the Vector Graph toolkit of genome Synteny and Collinearity, and its online service, to visualize the synteny and collinearity in the common graphical format, including both raster (JPEG, Bitmap, and PNG) and vector graphic (SVG, EPS, and PDF).
RESULTS
Users can upload sequence alignments from blast and collinearity relationship from the synteny analysis tools. The website can generate the vector or raster graphical results automatically. We also provide a java-based bytecode binary to enable the command-line execution.
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Publication
Journal: Gene
June/22/2015
Abstract
Increasing amounts of evidence have indicated that noncoding RNAs (ncRNAs) have important regulatory potential in various biological processes. However, the contributions of ncRNAs, especially long noncoding RNAs (lncRNAs), to peritoneal fibrosis remain largely unknown. The aim of this study was to investigate miRNA, lncRNA and mRNA expression profiles and their potential roles in the process of peritoneal fibrosis. Microarray expression profiles of the miRNAs, lncRNAs and mRNAs were determined in normal control peritoneum and in a mouse model of peritoneal dialysis fluid (PDF)-induced fibrotic peritoneum. Differential expression, pathway and gene network analyses were developed to identify possible functional RNA molecules in peritoneal fibrosis. Compared to the normal control, 232 lncRNAs (127 up-regulated and 105 down-regulated), 154 mRNAs (87 up-regulated and 67 down-regulated) and 15 miRNAs (14 miRNAs up-regulated and 1 down-regulated) were differentially expressed in the fibrotic peritoneum. Among the differentially expressed ncRNAs, 9 lncRNAs and 5 miRNAs were validated by real-time RT-PCR. Pathway analysis showed that the Jak-STAT, TGF-beta and MAPK signaling pathways had a close relationship with peritoneal fibrosis. Gene co-expression network analysis identified many genes, including JunB, HSP72, and Nedd9. It also identified lncRNAs AK089579, AK080622, and ENSMUST00000053838 and miRNAs miR-182 and miR-488. All of these species potentially play a key role in peritoneal fibrosis. Our results provide a foundation and an expansive view of the roles and mechanisms of ncRNAs in PDF-induced peritoneal fibrosis.
Publication
Journal: American Journal of Transplantation
April/14/2008
Abstract
Heme oxygenase-1 (HO-1) has been suggested as a cytoprotective gene during liver transplantation. Inducibility of HO-1 is modulated by a (GT)(n) polymorphism and a single nucleotide polymorphism (SNP) A(-413)T in the promoter. Both a short (GT)(n) allele and the A-allele have been associated with increased HO-1 promoter activity. In 308 liver transplantations, we assessed donor HO-1 genotype and correlated this with outcome variables. For (GT)(n) genotype, livers were divided into two classes: short alleles (<25 repeats; class S) and long alleles >> or =25 repeats; class L). In a subset, hepatic messenger ribonucleic acid (mRNA) expression was correlated with genotypes. Graft survival at 1 year was significantly better for A-allele genotype compared to TT-genotype (84% vs. 63%, p = 0.004). Graft loss due to primary dysfunction (PDF) occurred more frequently in TT-genotype compared to A-receivers (p = 0.03). Recipients of a liver with TT-genotype had significantly higher serum transaminases after transplantation and hepatic HO-1 mRNA levels were significantly lower compared to the A-allele livers (p = 0.03). No differences were found for any outcome variable between class S and LL-variant of the (GT)(n) polymorphism. Haplotype analysis confirmed dominance of the A(-413)T SNP over the (GT)(n) polymorphism. In conclusion, HO-1 genotype is associated with outcome after liver transplantation. These findings suggest that HO-1 mediates graft survival after liver transplantation.
Publication
Journal: Cell
January/25/2018
Abstract
O-glycosylation is one of the most abundant and diverse types of post-translational modifications of proteins. O-glycans modulate the structure, stability, and function of proteins and serve generalized as well as highly specific roles in most biological processes. This ShapShot presents types of O-glycans found in different organisms and their principle biosynthetic pathways. To view this SnapShot, open or download the PDF.
Publication
Journal: Journal of Insect Physiology
July/6/2003
Abstract
Pigment-dispersing factor (PDF) is an octadeca-neuropeptide widely distributed in the insect brain and suggested to be involved in the insect circadian systems. We have examined its effects on the neuronal activity of the brain efferents in the optic stalk including medulla bilateral neurons (MBNs) in the cricket, Gryllus bimaculatus. The MBNs are visually responding interneurons connecting the bilateral medulla, which show a clear day/night change in their light responsiveness that is greater during the night. Microinjection of PDF into the optic lobe induced a significant increase in the spontaneous activity of the brain efferents and the photo-responsiveness of the MBNs during the day, while little change was induced during the night. The enhancing effects began to occur about 20 min after the injection and another 10 min was necessary to reach the maximal level. The effects of PDF were dose-dependent. When 22 nl of anti-Gryllus-PDF (1:200) IgG was injected into the medulla, the photo-responsiveness of the MBNs was suppressed in both the day and the night with greater magnitude during the night. No significant suppression was induced by injection of the same amount of IgG from normal rabbit serum. These results suggest that in the cricket optic lobe, PDF is released during the night and enhances MBNs' photo-responsiveness to set their night state.
Publication
Journal: Neuron
July/31/2017
Abstract
We studied the Drosophila circadian neural circuit using whole-brain imaging in vivo. Five major groups of pacemaker neurons display synchronized molecular clocks, yet each exhibits a distinct phase of daily Ca2+ activation. Light and neuropeptide pigment dispersing factor (PDF) from morning cells (s-LNv) together delay the phase of the evening (LNd) group by ∼12 hr; PDF alone delays the phase of the DN3 group by ∼17 hr. Neuropeptide sNPF, released from s-LNv and LNd pacemakers, produces Ca2+ activation in the DN1 group late in the night. The circuit also features negative feedback by PDF to truncate the s-LNv Ca2+ wave and terminate PDF release. Both PDF and sNPF suppress basal Ca2+ levels in target pacemakers with long durations by cell-autonomous actions. Thus, light and neuropeptides act dynamically at distinct hubs of the circuit to produce multiple suppressive events that create the proper tempo and sequence of circadian pacemaker neuronal activities.
Publication
Journal: ACS Synthetic Biology
July/20/2017
Abstract
DNAplotlib ( www.dnaplotlib.org ) is a computational toolkit for the programmable visualization of highly customizable, standards-compliant genetic designs. Functions are provided to aid with both visualization tasks and to extract and overlay associated experimental data. High-quality output is produced in the form of vector-based PDFs, rasterized images, and animated movies. All aspects of the rendering process can be easily customized or extended by the user to cover new forms of genetic part or regulation. DNAplotlib supports improved communication of genetic design information and offers new avenues for static, interactive and dynamic visualizations that map and explore the links between the structure and function of genetic parts, devices and systems; including metabolic pathways and genetic circuits. DNAplotlib is cross-platform software developed using Python.
Publication
Journal: Clinical Orthopaedics and Related Research
May/15/2013
Abstract
This Classic Article is a translation of the original work by Franz König, "Ueber freie Körper in den Gelenken" [On loose bodies in the joint]. Dtsch Z Chir. 1887;27: 90-109. available at DOI 10.1007/s11999-013-2824-y (Translated by Drs. Richard A. Brand and Christian-Dominik Peterlein). An accompanying biographical sketch of F. König is available at DOI 10.1007/s11999-013-2823-z . A PDF of the original German is available as supplemental material. (ED Note: An attempt has been made to preserve some of the original wording while placing the material in a contemporary context. In some cases the author's original intent was obscure.).
Publication
Journal: International Journal of Molecular Sciences
July/1/2015
Abstract
The high-quality in vivo preclinical safety data produced by the pharmaceutical industry during drug development, which follows numerous strict guidelines, are mostly not available in the public domain. These safety data are sometimes published as a condensed summary for the few compounds that reach the market, but the majority of studies are never made public and are often difficult to access in an automated way, even sometimes within the owning company itself. It is evident from many academic and industrial examples, that useful data mining and model development requires large and representative data sets and careful curation of the collected data. In 2010, under the auspices of the Innovative Medicines Initiative, the eTOX project started with the objective of extracting and sharing preclinical study data from paper or pdf archives of toxicology departments of the 13 participating pharmaceutical companies and using such data for establishing a detailed, well-curated database, which could then serve as source for read-across approaches (early assessment of the potential toxicity of a drug candidate by comparison of similar structure and/or effects) and training of predictive models. The paper describes the efforts undertaken to allow effective data sharing intellectual property (IP) protection and set up of adequate controlled vocabularies) and to establish the database (currently with over 4000 studies contributed by the pharma companies corresponding to more than 1400 compounds). In addition, the status of predictive models building and some specific features of the eTOX predictive system (eTOXsys) are presented as decision support knowledge-based tools for drug development process at an early stage.
Publication
Journal: BMC Veterinary Research
December/18/2014
Abstract
BACKGROUND
During outbreak of livestock diseases, contact tracing can be an important part of disease control. Animal movements can also be of relevance for risk-based surveillance and sampling, i.e. both when assessing consequences of introduction or likelihood of introduction. In many countries, animal movement data are collected with one of the major objectives to enable contact tracing. However, often an analytical step is needed to retrieve appropriate information for contact tracing or surveillance.
RESULTS
In this study, an open source tool was developed to structure livestock movement data to facilitate contact-tracing in real time during disease outbreaks and for input in risk-based surveillance and sampling. The tool, EpiContactTrace, was written in the R-language and uses the network parameters in-degree, out-degree, ingoing contact chain and outgoing contact chain (also called infection chain), which are relevant for forward and backward tracing respectively. The time-frames for backward and forward tracing can be specified independently and search can be done on one farm at a time or for all farms within the dataset. Different outputs are available; datasets with network measures, contacts visualised in a map and automatically generated reports for each farm either in HTML or PDF-format intended for the end-users, i.e. the veterinary authorities, regional disease control officers and field-veterinarians. EpiContactTrace is available as an R-package at the R-project website (http://cran.r-project.org/web/packages/EpiContactTrace/).
CONCLUSIONS
We believe this tool can help in disease control since it rapidly can structure essential contact information from large datasets. The reproducible reports make this tool robust and independent of manual compilation of data. The open source makes it accessible and easily adaptable for different needs.
Publication
Journal: Journal of Sexual Medicine
August/13/2009
Abstract
BACKGROUND
Sexual dysfunction is a frequent but neglected problem in Parkinson's disease (PD). Decreased sexual desire in PD correlates with reduced general satisfaction from life. Many variables might be related to the loss of libido in PD and they have not been carefully investigated yet.
OBJECTIVE
To assess the frequency of loss of libido in PD and its relation to neurological symptoms, depression, anxiety, fatigue, and cognitive performance.
METHODS
The response of 90 PD patients of both genders to item "loss of libido" from the Beck Depression Inventory (BDI) was analyzed. A structured psychiatric interview (MINI-Plus) evaluated the presence of major depression and generalized anxiety disorder. Clinical assessment also comprised neurological examination, which included all sections of the Unified Parkinson's Disease Rating Scale (UPDRS), Hoehn-Yahr and Schwab-England Scale (SES). The Frontal Assessment Battery (FAB), the Mini Mental State Examination (MMSE), and the PD Fatigue Scale (PDFS) were also performed.
METHODS
Frequency of loss of libido and its main predictors.
RESULTS
The frequency of loss of libido was 65.6%, and 42.6% of men also complained of erectile dysfunction. Ageing (P = 0.012), female gender (P < 0.001), lower education (P < 0.001), and depression (P = 0.006) associated with decreased sexual desire. Higher BDI scores (P < 0.001) correlated with a greater loss of libido. Decreased interest in sex was not associated with antidepressants. Neurological features associated with higher loss of libido were predominance of motor symptoms on the left side of the body (P = 0.026), autonomic dysfunction (P = 0.012), higher UPDRS scores (P = 0.006), and lower scores on SES (P = 0.003). In men, erectile dysfunction associated with decreased interest in sex (P < 0.001). Patients with lower performance on FAB (P < 0.001) and MMSE (P = 0.002), and with higher scores on PDFS (P < 0.001) also had less interest in sex. A multiple regression analysis indicated age, gender and BDI score as the main predictors of loss of libido.
CONCLUSIONS
Loss of libido is frequent in PD and depression may be its main predictor. However, decreased interest in sex was not associated with antidepressant therapy. Thus, loss of libido resulting from depression may be effectively treated, and physicians should be encouraged to assess these symptoms in their patients.
Publication
Journal: Bioinformatics
August/4/2013
Abstract
BACKGROUND
Biochemical reaction networks in the form of coupled ordinary differential equations (ODEs) provide a powerful modeling tool for understanding the dynamics of biochemical processes. During the early phase of modeling, scientists have to deal with a large pool of competing nonlinear models. At this point, discrimination experiments can be designed and conducted to obtain optimal data for selecting the most plausible model. Since biological ODE models have widely distributed parameters due to, e.g. biologic variability or experimental variations, model responses become distributed. Therefore, a robust optimal experimental design (OED) for model discrimination can be used to discriminate models based on their response probability distribution functions (PDFs).
RESULTS
In this work, we present an optimal control-based methodology for designing optimal stimulus experiments aimed at robust model discrimination. For estimating the time-varying model response PDF, which results from the nonlinear propagation of the parameter PDF under the ODE dynamics, we suggest using the sigma-point approach. Using the model overlap (expected likelihood) as a robust discrimination criterion to measure dissimilarities between expected model response PDFs, we benchmark the proposed nonlinear design approach against linearization with respect to prediction accuracy and design quality for two nonlinear biological reaction networks. As shown, the sigma-point outperforms the linearization approach in the case of widely distributed parameter sets and/or existing multiple steady states. Since the sigma-point approach scales linearly with the number of model parameter, it can be applied to large systems for robust experimental planning.
BACKGROUND
An implementation of the method in MATLAB/AMPL is available at http://www.uni-magdeburg.de/ivt/svt/person/rf/roed.html.
BACKGROUND
flassig@mpi-magdeburg.mpg.de
BACKGROUND
Supplementary data are are available at Bioinformatics online.
Publication
Journal: Journal of Neuroscience
March/3/2013
Abstract
The neuropeptide pigment-dispersing factor (PDF) synchronizes molecular oscillations within circadian pacemakers in the Drosophila brain. It is expressed in the small ventral lateral neurons (sLNvs) and large ventral lateral neurons, the former being indispensable for maintaining behavioral rhythmicity under free-running conditions. How PDF circuits develop the specific connectivity traits that endow such global behavioral control remains unknown. Here, we show that mature sLNv circuits require PDF signaling during early development, acting through its cognate receptor PDFR at postsynaptic targets. Yet, axonal defects by PDF knockdown are presynaptic and become apparent only after metamorphosis, highlighting a delayed response to a signal released early on. Presynaptic expression of constitutively active bone morphogenetic protein (BMP) receptors prevents pdfr mutants misrouting phenotype, while sLNv-restricted downregulation of BMP signaling components phenocopied pdf(01). Thus, we have uncovered a novel mechanism that provides an early "tagging" of synaptic targets that will guide circuit refinement later in development.
Publication
Journal: International Journal of Legal Medicine
August/16/2011
Abstract
The admixed Brazilian population shows high levels of genetic variability, which resulted from the contribution of three main ethnicities, Amerindian, European, and African. However, due to its huge territory, admixing has been asymmetrical, i.e., the relative contribution from each ethnicity has been unequal in the five geopolitical regions of the country. The aim of this study was to describe genetic variability using a panel of short-tandem repeats on the X chromosome (X-STR) in order to perform a comprehensive evaluation of the usefulness of such markers for forensic purposes in Brazil. Twelve X-STR (DXS9895, DXS7132, DXS6800, DXS9898, DXS6789, DXS7133, GATA172D05, DXS7130, HPRTB, GATA31E08, DXS7423, and DXS10011) were chosen and tested in a sample of 2,234 individuals belonging to 16 out of the 27 Brazilian States, representing all of its five geopolitical regions. No markers showed significant deviation from the Hardy-Weinberg equilibrium, even when analyses were partitioned to represent geopolitical regions. Genetic diversity per locus ranged from 67% (DSX7133) to 95% (DXS10011), and the State of Ceará showed the highest average genetic diversity (79% for all 12 X-STR markers). Considering the Brazilian population as a whole, the power of discrimination of the 12 X-STR panel in females (PDF) was 0.999999999999994, while the power of discrimination in males (PDM) was 0.9999999969. Such high values suggest the potential of that panel to be used in forensic applications and relatedness tests among individuals. Comparisons among the Brazilian populations investigated revealed significant differences when they were compared among each other, a pattern that was maintained when additional populations from Europe and Latin America were compared to Brazilians. Our results highlight the need and usefulness of specific genetic database for forensic purposes in Brazilian populations.
Publication
Journal: American Journal of Sports Medicine
November/2/2014
Abstract
BACKGROUND
With the recent emphasis on performing open reduction and internal fixation on midshaft clavicle fractures with complete displacement, comminution, and >2 cm of shortening, it is important to determine the reliability of orthopaedic surgeons to assess these variables on standard plain radiographs and to determine the agreement among orthopaedic surgeons in choosing the treatment.
OBJECTIVE
To determine the intra- and interobserver reliability in the classification of midshaft clavicle fractures via standard plain radiographs and to determine the intra- and interobserver agreement in the treatment of these fractures.
METHODS
Cohort study (diagnosis); Level of evidence, 3.
METHODS
Charts of patients seen by the 2 senior authors from 2006 to 2011 were reviewed to identify patients treated for clavicle fractures (CPT codes 23500 and 23515). Anteroposterior and 30° cephalad radiographs were selected, representing midshaft clavicle fractures treated both operatively and nonoperatively. Thirty pairs of radiographs were included in the investigation. The radiographs were standardized for size to allow accurate measurements within a non-PACS (picture archiving and communications system) program, and a PDF document was created with all representative radiographs. Clinical scenarios were created for each set of radiographs, and the evaluators were asked to (1) measure the degree of shortening in millimeters, (2) determine the percentage displacement, (3) determine whether the fracture was comminuted, and (4) state whether they would treat the fracture operatively or nonoperatively. The radiographs, along with instructions on how to use the measuring tool with Adobe Reader, were distributed to 22 shoulder/sports medicine fellowship-trained orthopaedic surgeons, then reordered and redistributed approximately 3 months later. Sixteen surgeons completed 1 round of surveys, and 13 surgeons completed both rounds.
RESULTS
Interrater agreement was moderate for displacement of 0%-49% (κ = 0.71, P < .001) and >100% (κ = 0.73, P < .001), with minimal agreement for displacement of 50%-100% (κ = 0.39, P < .001). There was moderate interrater agreement for the presence/absence of comminution (κ = 0.75, P < .001). Interrater agreement was weak for shortening of 0-5.0 mm (κ = 0.58, P < .001) and >30.0 mm (κ = 0.51, P < .001), with minimal agreement for shortening of 5.1-10.0 mm (κ = 0.22, P < .001) and no agreement for the other 4 categories. Interrater analysis showed weak agreement on whether surgical treatment was recommended (κ = 0.40, P < .001). Intrarater agreement was strong for comminution (κ = 0.80, P < .0001), moderate for both displacement (κ = 0.76, P < .001) and operative treatment (κ = 0.64, P < .001), and minimal for shortening (κ = 0.38, P < .001). The following variables statistically predicted whether surgery was recommended (P < .001): (1) the odds of surgery were 2.26 if comminution was noted, holding displacement and the interaction between displacement and shortening constant, and (2) the odds of surgery were 3.37 if there is displacement of >100% compared with displacement of 0%-49%, holding comminution and shortening constant.
CONCLUSIONS
Standard plain unilateral radiographs of the clavicle are insufficient to reliably determine the degree of shortening of clavicle fractures and the need for surgery among shoulder/sports medicine fellowship-trained orthopaedic surgeons. Consideration should be made to not use shortening as the sole determinant for whether to proceed with surgical intervention or to use other radiographic modalities to determine the amount of shortening.
Publication
Journal: Journal of Comparative Neurology
September/12/2007
Abstract
This paper reports the localization in the Rhodnius prolixus brain of neurons producing the key neuropeptide that regulates insect development, prothoracicotropic hormone (PTTH) and describes intimate associations of the PTTH neurons with the brain circadian timekeeping system. Immunohistochemistry and confocal laser scanning microscopy revealed that the PTTH-positive neurons in larvae are located in a single group in the lateral protocerebrum. Their number increases from two in the last larval instar to five during larval-adult development. In adults, there are two distinct groups of these neurons composed of two cells each. A daily rhythm in content of PTTH-positive material occurs in both the somata and the axons in both larval and adult stages. These rhythms correlate with previous evidence of a circadian rhythm of PTTH release from brains in vitro. The key circadian clock cells of Rhodnius are eight neurons, which co-express pigment-dispersing factor (PDF) and the canonical clock proteins PER and TIM; PDF fills the axons. Equivalent cells control behavioral rhythms in other insects. Double labeling revealed intimate associations between axons of larval PTTH neurons and clock neurons, indicating a neuronal pathway from the brain timekeeping system for circadian control of PTTH release. Additional PDF neurons appear in the adult, associated with the second group of PTTH neurons. These findings provide the first direct evidence that neurons of the insect brain timekeeping system control hormone rhythms. The range of functions regulated by this timekeeping system is quite similar to those of the vertebrate suprachiasmatic nucleus, for which the insect system is a valuable model.
Publication
Journal: Brain Research Bulletin
May/29/2013
Abstract
The probability density function (PDF) of the surface electromyogram (EMG) signals has been modelled with Gaussian and Laplacian distribution functions. However, a general consensus upon the PDF of the EMG signals is yet to be reached, because not only are there several biological factors that can influence this distribution function, but also different analysis techniques can lead to contradicting results. Here, we recorded the EMG signal at different isometric muscle contraction levels and characterised the probability distribution of the surface EMG signal with two statistical measures: bicoherence and kurtosis. Bicoherence analysis did not help to infer the PDF of measured EMG signals. In contrast, with kurtosis analysis we demonstrated that the EMG PDF at isometric, non-fatiguing, low contraction levels is super-Gaussian. Moreover, kurtosis analysis showed that as the contraction force increases the surface EMG PDF tends to a Gaussian distribution.
Publication
Journal: Academic Radiology
July/6/2006
Abstract
OBJECTIVE
Electronic learning (e-learning) may provide a means to enhance learning efficacy. However, introduction of e-learning often fails. We describe a strategy of how an e-learning curriculum was successfully implemented.
METHODS
The curriculum was designed based on published evidence. It consists of self-directed learning, an online discussion forum, and discussion rounds. The e-content in nuclear medicine and radiotherapy was produced by the k-MED team of medical authors, web designers, and psychologists. The online courses were delivered via a dedicated learning management system. The e-content for diagnostic radiology and physics was provided as PDF/HTML script by the respective teachers who objected to participate in the k-MED project. The exam was taken online. Online evaluation of the curriculum by the students was taken at the end of the course.
RESULTS
The new curriculum proved very effective. The time for the preparation for the clinical part of the radiology course could be reduced from 4 to 2 weeks. The students particularly enjoyed the self-directed learning. Although the material provided by k-MED received 90%-99% positive scores, the HTML and PDF scripts scored worse (13%-67% positive ratings). The positive results of the evaluation convinced the teachers responsible for physics and diagnostic radiology to participate in k-MED.
CONCLUSIONS
As our example shows, new e-learning curricula can successfully be introduced. The strategy of implementation should be based on the existing evidence from the literature. The new curriculum helped to increase the efficacy of teaching and save time as the duration of the respective part of the course could be reduced by half.
Publication
Journal: Journal of Experimental Medicine
June/22/2010
Abstract
For convenience the results are summarized in tabular form. Table I shows a comparison of the primary reaction in the groups of female and male rabbits inoculated intradermally. In Table II the incidence of metastatic lesions is shown in the various groups of animals. In Table III are shown the character and date of appearance of the generalized lesions (exclusive of orchitis) in the various groups of animals. The results presented in Tables I, II, and III, together with a study of the individual protocols, permit the following general statements to be made relative to the effect of the factors studied upon the course of experimental syphilis in the rabbit. Sex.-In the group of females inoculated intradermally the lesions at the site of inoculation were in general less marked than in the group of males similarly inoculated. Moreover, they attained their maximum size earlier and began to recede earlier than was the case in the males. In none of the females was there clinical evidence of the production of generalized lesions, while in the corresponding group of males metastatic lesions of skin or bones detectible by clinical examination occurred in one instance, or 14.3 per cent. In both groups there was wide variation in the character of the initial reaction in individual rabbits and in the time required for it to reach its maximum size. See PDF for Structure Age.-In the five young males inoculated intratesticularly the disease was not greatly different from that observed in the older males similarly inoculated. The initial reactions were slightly slower in making their appearance, but the magnitude of the reaction, as judged by enlargement of the testicles, was somewhat greater. The percentage incidence of metastatic orchitis was almost the same in the two groups. The younger animals showed a slightly greater incidence of generalized lesions involving structures other than the testicles, although the difference was insignificant, but the lesions were smaller, fewer in number, and confined entirely to the skin, and there was no instance of severe generalized lesions. Moreover, the occurrence of metastatic lesions (skin) in the younger animals was definitely delayed. Method of Injection.-In the animals inoculated by the intratesticular route the development of the primary reaction and the incidence of generalized lesions involving skin and bone were much greater than in See PDF for Structure the animals inoculated intradermally. Thus, of the latter group only one, or 14.3 per cent, showed a secondary metastatic lesion (skin), while in the group inoculated by the testicular route the incidence of metastatic skin and bone lesions was as high as 71.4 per cent. The difference in the character of the disease exhibited by these two groups of animals inoculated in a different manner is quite striking. Intratesticular inoculation produced a much more violent local reaction and a much greater incidence of generalized lesions than did intradermal inoculation. Effect of Castration.-In the group of animals with unilateral orchitis in which the infection was allowed to run its course without any attempt at suppression by removal of the initial focus, metastatic lesions appeared more promptly and in slightly greater incidence than See PDF for Structure in the group of animals in which the initial local reaction was suppressed by removal of the focus itself through castration. The percentage differences are not very great, but they are constantly in favor of the first group, as is the time interval of appearance. This experiment is not in strict accord with similar experiments observed by Brown and Pearce (3) in the past, and while the reasons for this difference are not clear the fact may be noted that the incidence of generalized lesions in uncastrated animals is somewhat higher than that reported by these authors, also that there was a high percentage of recurrence of primary lesions.
Publication
Journal: PLoS Biology
August/3/2014
Abstract
Living organisms use biological clocks to maintain their internal temporal order and anticipate daily environmental changes. In Drosophila, circadian regulation of locomotor behavior is controlled by ∼150 neurons; among them, neurons expressing the PIGMENT DISPERSING FACTOR (PDF) set the period of locomotor behavior under free-running conditions. To date, it remains unclear how individual circadian clusters integrate their activity to assemble a distinctive behavioral output. Here we show that the BONE MORPHOGENETIC PROTEIN (BMP) signaling pathway plays a crucial role in setting the circadian period in PDF neurons in the adult brain. Acute deregulation of BMP signaling causes period lengthening through regulation of dClock transcription, providing evidence for a novel function of this pathway in the adult brain. We propose that coherence in the circadian network arises from integration in PDF neurons of both the pace of the cell-autonomous molecular clock and information derived from circadian-relevant neurons through release of BMP ligands.
Publication
Journal: Optometry and Vision Science
January/9/2006
Abstract
OBJECTIVE
A number of automated perimeters use the Zippy Estimation by Sequential Testing (ZEST) algorithm, which is an adaptive Bayesian method, for determining sensitivity measures. There are two popular rules for deciding when to terminate Bayesian procedures: (1) after a fixed number of presentations; or (2) when the probability density function (pdf) over all thresholds modified by the procedure becomes sufficiently narrow (a dynamic termination criterion). It has recently been argued that fixed termination criteria perform equally as well as dynamic criteria when applied in a fashion typical of laboratory-based visual psychophysics. Perimetry, however, has specific requirements; the tests must be very short, there is a wide range of possible sensitivities, and erroneous responses from the patient must be tolerated. This study used computer simulation to compare fixed and dynamic termination criteria for the ZEST algorithm using conditions typical of white-on-white perimetry.
METHODS
Eight ZEST procedures were compared using the following termination criteria: fixed termination after 4, 5, 6, 7, and 8 presentations; dynamic termination when the standard deviation of the pdf was 1 dB, 1.5 dB, and 2 dB. Four patient error models were used: ideal, typical false-positive, typical false-negative, and unreliable patients. We also ran a version of ZEST that set the likelihood function exactly equal to the patient's frequency of seeing curve.
RESULTS
The mean absolute error and standard deviation of error in threshold measurement was higher for the fixed termination criteria than for dynamic termination criteria of the same average number of presentations.
CONCLUSIONS
The results of our simulations indicate that dynamic procedures have some distinct benefits over fixed termination procedures when a minimum of presentations are required and response errors are made as in a white-on-white perimetric setting. Dynamic termination criteria are at least partially successful in expending more presentations when required to enhance test precision.
Publication
Journal: Molecular and Cellular Neurosciences
July/27/2009
Abstract
The LARK RNA-binding protein (RBP) has well documented roles in the circadian systems of Drosophila and mammals. Recent studies have demonstrated that the Drosophila LARK RBP is associated with many mRNA targets, in vivo, including those that regulate either neurophysiology or development of the nervous system. In the present study, we have employed conditional expression techniques to distinguish developmental and physiological functions of LARK for a defined class of neurons: the Pigment-Dispersing Factor (PDF)-containing LNv clock neurons. We found that increased LARK expression during development dramatically alters the small LNv class of neurons with no obvious effects on the large LNv cells. Conversely, conditional expression of LARK at the adult stage results in altered clock protein rhythms and circadian locomotor activity, even though neural morphology is normal in such animals. Electrophysiological analyses at the larval neuromuscular junction indicate a role for LARK in regulating neuronal excitability. Altogether, our results demonstrate that LARK activity is critical for neuronal development and physiology.
Publication
Journal: Journal of Biological Rhythms
March/22/2006
Abstract
The authors report the results of their study aimed at investigating the consequence of targeted ablation of ventral lateral neurons (LN(v)s--neurons regulating eclosion and locomotor activity rhythms) and genetic disruption of pigment-dispersing factor (PDF--an important output of circadian clocks) on the egg-laying rhythm of Drosophila melanogaster. The results clearly suggest that genetic ablation of LN(v)s and loss of function mutation of PDF abolish eclosion and locomotor activity rhythms, whereas the egg-laying rhythm continues unabated. Furthermore, the results also demonstrate that the period of egg-laying rhythm remains unchanged under different ambient temperatures and nutrition levels, suggesting that the egg-laying rhythm of D. melanogaster is temperature and nutrition compensated. Based on these results, the authors conclude that the egg-laying rhythm in D. melanogaster is regulated by non-LN(v)-based, non-PDF-mediated circadian clocks.
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