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Reinnervation of original synaptic sites on muscle fiber basement membrane after disruption of the muscle cells.

Marshall, L M; Sanes, J R; McMahan, U J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1977 EN
Relevância na Pesquisa
45.41%
Regenerating axons form new synapses precisely at sites of original synapses in denervated skeletal muscle. To determine what role the muscle cell plays in this phenomenon, we studied reinnervation of frog muscle at intervals after crushing the nerve and damaging the muscle fibers. Damaged muscle fibers degenerate and are phagocytized, but their basement membrane persists and acts as a scaffold for regenerating muscle cells. Specializations of the basement membrane serve to mark original synaptic sites after nerve and muscle have degenerated. Regenerating axons enter the region of damage and form functional synapses with regenerating myofibers. The new nerve terminals are found almost exclusively at the original synaptic sites, demonstrating that the integrity of the original postsynaptic cell is not necessary for topographically precise reinnervation of denervated muscle.

Auditing the British Medical Journal.

Channer, K S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1994 EN
Relevância na Pesquisa
45.41%
The purpose of this study was to audit the outcome in terms of change in practice of the published research from one volume of the British Medical Journal. All original papers and short reports from one Volume 296 of the British Medical Journal (BMJ) 1988 were read and classified into theoretical only, practical and theoretical and practical. Those papers with any practical message were reviewed by one of a panel of specialists in the subject of the paper to assess if the recommendation made by the paper had become common clinical practice. The results show that most papers originated from teaching centres and research institutes in the UK. Only 8% of main papers and 6% of short reports had a solely practical application, although a further 18% and 22% had practical elements. The majority of the recommendations aimed at changing practice were of relevance to hospital specialists rather than general practitioners (GPs). Of the papers with any practical implications 48% (12% of the total) of main papers and 41% (11% of the total) of short reports were considered to be current practice. The reasons why the papers failed to change practice are discussed. In conclusion, the majority of the original research papers published in the BMJ in 1988 were of a theoretical nature and only about 20% of papers made recommendations for a change in practice. About 50% of the recommendations are now current practice.

The interaction between foreign and original motor nerves innervating the soleus muscle of rats.

Frank, E; Jansen, J K; Lono, T; Westgaard, R H
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/1975 EN
Relevância na Pesquisa
45.44%
1. The fibular nerve was transplanted on to the soleus muscle of the rats. Interruption of the original soleus nerve then permitted cross-innervation, and subsequently, over a period of weeks, re-innervation by the original nerve. 2. Individual muscle fibres were often innervated by both the original and the foreign nerve. The original and foreign end-plates were located in separate regions of the muscle. There were no indications that the original nerve could displace or repress the foreign innervation. 3. The extent of re-innervation by the original nerve depended upon the method of denervation. A single crush of the nerve was followed by virtually complete re-innervation, even of muscle fibres already innervated by the foreign nerve. When re-innervation was delayed by resection of a segment of the nerve only muscle fibres without foreign nerve innervation were re-innervated. Denervation by a simple nerve cut gave an intermediate result. 4. Re-innervation by the original nerve can take place without measurable extrajunctional sensitivity to ACh. 5. The original end-plate region could retain high and localized sensitivity to ACh for several months despite degeneration of its motor nerve terminal and activity of the muscle fibre. 6. Established foreign end-plates were re-innervated by the foreign nerve on muscle fibres with intact original innervation. 7. The factors controlling synapse formation in skeletal muscles are discussed.

Effectiveness of interventions to prevent delirium in hospitalized patients: a systematic review.

Cole, M G; Primeau, F; McCusker, J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 01/11/1996 EN
Relevância na Pesquisa
55.35%
OBJECTIVE: To determine the effectiveness of interventions to prevent delirium in hospitalized patients. DATA SOURCES: Two databases, MEDLINE and CINAHL, were searched for relevant articles published from January 1966 to May 1995 and from January 1982 to May 1995 respectively. The bibliographies of identified articles were searched for additional references. STUDY SELECTION: Ten articles met the following three inclusion criteria: (a) original research article, (b) published in English or French and (c) controlled trial (nonrandomized or randomized) of an intervention to prevent delirium in hospitalized patients. The validity of the studies was independently assessed according to the criteria for intervention studies proposed by the Evidence-Based medicine Working Group. DATA EXTRACTION: Information about study design, patient population, sample size, diagnostic criteria, interventions and results was systematically abstracted from each report. Absolute risk reduction (ARR) for delirium was calculated for each study. DATA SYNTHESIS: Eight trials involved surgical patients and two involved elderly medical patients; most of the studies had serious methodological limitations. Among the surgical patients the ARRs ranged from -13% to 81% and were not related to the type or timing of the intervention...

Quality of nonstructured and structured abstracts of original research articles in the British Medical Journal, the Canadian Medical Association Journal and the Journal of the American Medical Association.

Taddio, A; Pain, T; Fassos, F F; Boon, H; Ilersich, A L; Einarson, T R
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/05/1994 EN
Relevância na Pesquisa
65.41%
OBJECTIVE: To assess and compare the quality of nonstructured and structured abstracts of original research articles in three medical journals. DESIGN: Blind, criterion-based observational study. SAMPLE: Random sample of 300 abstracts (25 abstracts per journal each year) of articles published in the British Medical Journal (BMJ), the Canadian Medical Association Journal and the Journal of the American Medical Association (JAMA) in 1988 and 1989 (nonstructured abstracts) and in 1991 and 1992 (structured abstracts). MAIN OUTCOME MEASURES: The quality of abstracts was measured against 33 objective criteria, which were divided into eight categories (purpose, research design, setting, subjects, intervention, measurement of variables, results and conclusions). The quality score was determined by dividing the number of criteria present by the number applicable; the score varied from 0 to 1. RESULTS: The overall mean quality scores for nonstructured and structured abstracts were 0.57 and 0.74 respectively (p < 0.001). The frequency in meeting the specific criteria was generally higher for the structured abstracts than for the nonstructured ones. The mean quality score was higher for nonstructured abstracts in JAMA than for those in BMJ (0.60 v. 0.54...

Scientific quality of original research articles on environmental tobacco smoke

Barnes, D. E.; Bero, L. A.
Fonte: BMJ Group Publicador: BMJ Group
Tipo: Artigo de Revista Científica
Publicado em /03/1997 EN
Relevância na Pesquisa
45.48%
OBJECTIVE: To evaluate the scientific quality of original research articles on the health effects of environmental tobacco smoke; to determine whether poor article quality is associated with publication in non-peer-reviewed symposium proceedings or with other article characteristics. DESIGN: Cross sectional study of original research articles on the health effects of environmental tobacco smoke published in peer reviewed journals and non-peer-reviewed symposium proceedings from 1980 to 1994. Article quality was assessed by two independent reviewers who used a valid and reliable instrument, were unaware of study hypotheses, were blinded to identifying characteristics of articles, and had no disclosed conflicts of interest. PARTICIPANTS: All symposium articles (n = 68) and a random sample of peer reviewed journal articles (n = 68) that satisfied inclusion/exclusion criteria. MAIN OUTCOME MEASURE: Mean quality scores, which could range from 0 (lowest quality) to 1 (highest quality). RESULTS: Using multivariate regression analysis, symposium articles were of poorer scientific quality than peer reviewed journal articles when controlling simultaneously for the effects of study design, article conclusion, article topic, and source of funding acknowledged (P = 0.027). Article quality was not associated with either source of funding acknowledged or article conclusion in multivariate analyses. CONCLUSIONS: In published reports on environmental tobacco smoke...

Nuclear magnetic resonance studies of glucose metabolism in non-insulin-dependent diabetes mellitus subjects.

Shulman, R. G.
Fonte: The Feinstein Institute for Medical Research Publicador: The Feinstein Institute for Medical Research
Tipo: Artigo de Revista Científica
Publicado em /09/1996 EN
Relevância na Pesquisa
55.34%
In this review, the results of a series of NMR experiments investigating glucose storage and synthesis in NIDDM patients and normal controls have been summarized. These have shown: 1. The deficit in nonoxidative glucose disposal in NIDDM subjects results from a defect in the muscle glycogen synthesis pathway. 2. Reduced activity of glucose transporter/hexokinase step in this pathway accounts for the reduced rate of glycogen synthesis in NIDDM patients. 3. This reduced activity of GT/Hk is a genetic defect present before the clinical onset of disease in prediabetic descendants of diabetic parents. 4. In muscle from normal, healthy subjects the rate of glycogen synthesis is controlled by the glucose transport/hexokinase activity step and not by the activity of the muscle glycogen synthase enzyme. 5. Hepatic gluconeogenesis is responsible for most hepatic glucose production during an overnight fast in both normal and NIDDM subjects, and increases in gluconeogenic flux are responsible for the increased rate of hepatic glucose production in NIDDM subjects. 6. In contrast to human muscle, where glycogenesis ceases at rest, in the liver gluconeogenesis and glycogenolysis are always active. Numerous previous studies were considered prior to embarking in each of these NMR experiments. In the original research articles we published...

Adjustment and Characterization of an Original Model of Chronic Ischemic Heart Failure in Pig

Barandon, Laurent; Calderon, Joachim; Réant, Patricia; Caillaud, Dominique; Lafitte, Stéphane; Roques, Xavier; Couffinhal, Thierry; Dos Santos, Pierre
Fonte: SAGE-Hindawi Access to Research Publicador: SAGE-Hindawi Access to Research
Tipo: Artigo de Revista Científica
Publicado em 07/09/2010 EN
Relevância na Pesquisa
55.38%
We present and characterize an original experimental model to create a chronic ischemic heart failure in pig. Two ameroid constrictors were placed around the LAD and the circumflex artery. Two months after surgery, pigs presented a poor LV function associated with a severe mitral valve insufficiency. Echocardiography analysis showed substantial anomalies in radial and circumferential deformations, both on the anterior and lateral surface of the heart. These anomalies in function were coupled with anomalies of perfusion observed in echocardiography after injection of contrast medium. No demonstration of myocardial infarction was observed with histological analysis. Our findings suggest that we were able to create and to stabilize a chronic ischemic heart failure model in the pig. This model represents a useful tool for the development of new medical or surgical treatment in this field.

Scope and Impact of International Research in Human Pluripotent Stem Cells

Löser, Peter; Kobold, Sabine; Guhr, Anke; Müller, Franz-Josef; Kurtz, Andreas
Fonte: Humana Press Inc Publicador: Humana Press Inc
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.43%
In a recent study published in this journal it was claimed that the rate of publications from US-based authors in the human embryonic stem cell (hESC) research field was slowing or even declining from 2008 to 2010. It was assumed that this is the result of long-term effects of the Bush administration’s funding policy for hESC research and the uncertain policy environment of recent years. In the present study, we analyzed a pool of more than 1,700 original hESC research papers published world-wide from 2007 to 2011. In contrast to the previous study, our results do not support the hypothesis of a decline in the productivity of US-based research but rather confirm a nearly unchanged leading position of US research in the hESC field with respect to both publication numbers and impact of research. Moreover, we analyzed about 500 papers reporting original research involving human induced pluripotent stem cells (hiPSCs) published through 2011 and found a dominant position of US research in this research field as well.

Publication of Original Research in Urologic Journals – A Neglected Orphan?

Mani, Jens; Makarević, Jasmina; Juengel, Eva; Ackermann, Hanns; Nelson, Karen; Haferkamp, Axel; Blaheta, Roman A.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 19/12/2012 EN
Relevância na Pesquisa
55.48%
The pathophysiologic mechanisms behind urologic disease are increasingly being elucidated. The object of this investigation was to evaluate the publication policies of urologic journals during a period of progressively better understanding and management of urologic disease. Based on the ISI Web of Knowledge Journal Citation Reports and the PubMed database, the number and percentage of original experimental, original clinical, review or commentarial articles published between 2002–2010 in six leading urologic journals were analyzed. “British Journal of Urology International”, “European Urology”, “Urologic Oncology-Seminars and Original Investigations” (“Urologic Oncology”), “Urology”, “The Journal of Urology”, and “World Journal of Urology” were chosen, because these journals publish articles in all four categories. The publication policies of the six journals were very heterogeneous during the time period from 2002 to 2010. The percentage of original experimental and original clinical articles, related to all categories, remained the same in “British Journal of Urology International”, “Urologic Oncology”, “Urology” and “The Journal of Urology”. The percentage of experimental reports in “World Journal of Urology” between 2002–2010 significantly increased from 10 to 20%. A distinct elevation in the percentage of commentarial articles accompanied by a reduction of clinical articles became evident in “European Urology” which significantly correlated with a large increase in the journal’s impact factor. No clearly superior policy could be identified with regard to a general increase in the impact factors from all the journals. The publication policy of urologic journals does not expressly reflect the increase in scientific knowledge...

Social Media Release Increases Dissemination of Original Articles in the Clinical Pain Sciences

Allen, Heidi G.; Stanton, Tasha R.; Di Pietro, Flavia; Moseley, G. Lorimer
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 17/07/2013 EN
Relevância na Pesquisa
55.38%
A barrier to dissemination of research is that it depends on the end-user searching for or ‘pulling’ relevant knowledge from the literature base. Social media instead ‘pushes’ relevant knowledge straight to the end-user, via blogs and sites such as Facebook and Twitter. That social media is very effective at improving dissemination seems well accepted, but, remarkably, there is no evidence to support this claim. We aimed to quantify the impact of social media release on views and downloads of articles in the clinical pain sciences. Sixteen PLOS ONE articles were blogged and released via Facebook, Twitter, LinkedIn and ResearchBlogging.org on one of two randomly selected dates. The other date served as a control. The primary outcomes were the rate of HTML views and PDF downloads of the article, over a seven-day period. The critical result was an increase in both outcome variables in the week after the blog post and social media release. The mean ± SD rate of HTML views in the week after the social media release was 18±18 per day, whereas the rate during the other three weeks was no more than 6±3 per day. The mean ± SD rate of PDF downloads in the week after the social media release was 4±4 per day, whereas the rate during the other three weeks was less than 1±1 per day (p<0.05 for all comparisons). However...

ExoCarta as a resource for exosomal research

Simpson, Richard J.; Kalra, Hina; Mathivanan, Suresh
Fonte: Co-Action Publishing Publicador: Co-Action Publishing
Tipo: Artigo de Revista Científica
Publicado em 16/04/2012 EN
Relevância na Pesquisa
55.36%
Exosomes are a class of extracellular vesicles that are secreted by various cell types. Unlike other extracellular vesicles (ectosomes and apoptotic blebs), exosomes are of endocytic origin. The roles of exosomes in vaccine/drug delivery, intercellular communication and as a possible source of disease biomarkers have sparked immense interest in them, resulting in a plethora of studies. Whilst multidimensional datasets are continuously generated, it is difficult to harness the true potential of the data until they are compiled and made accessible to the biomedical researchers. Here, we describe ExoCarta (http://www.exocarta.org), a manually curated database of exosomal proteins, RNA and lipids. Datasets currently present in ExoCarta are integrated from both published and unpublished exosomal studies. Since its launch in 2009, ExoCarta has been accessed by more than 16,000 unique users. In this article, we discuss the utility of ExoCarta for exosomal research and urge biomedical researchers in the field to deposit their datasets directly to ExoCarta.

Editorial Decisions May Perpetuate Belief in Invalid Research Findings

Eriksson, Kimmo; Simpson, Brent
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 04/09/2013 EN
Relevância na Pesquisa
45.44%
Social psychology and related disciplines are seeing a resurgence of interest in replication, as well as actual replication efforts. But prior work suggests that even a clear demonstration that a finding is invalid often fails to shake acceptance of the finding. This threatens the full impact of these replication efforts. Here we show that the actions of two key players – journal editors and the authors of original (invalidated) research findings – are critical to the broader public’s continued belief in an invalidated research conclusion. Across three experiments, we show that belief in an invalidated finding falls sharply when a critical failed replication is published in the same – versus different – journal as the original finding, and when the authors of the original finding acknowledge that the new findings invalidate their conclusions. We conclude by discussing policy implications of our key findings.

Foundational principles of classical Ayurveda research

Raha, Somik
Fonte: Medknow Publications & Media Pvt Ltd Publicador: Medknow Publications & Media Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
55.35%
Double-blind randomized controlled trials (RCTs) are viewed as the golden standard of drug research in Western medicine. However, RCTs are far from “golden” in many respects. They are impractical for many therapies, such as for surgeries and complex lifestyle changes. They encourage a one-size-fits-all approach to medical treatment that fails to address the huge diversity among individual patients in terms of their physical and emotional symptoms, social and cultural upbringing, and other factors. Perhaps, more importantly, they do not help doctors make the best medical decisions required to produce optimal patient outcomes. To guide a search for an alternate model of medical research, three principles based on Ayurveda, an ancient and powerful system of health care that has stood the test of time, are presented. These principles, arrived at after mining Ayurvedic epistemology, are: Inductive learning, whole systems thinking, and individually optimized therapy. In honor of the ancient sages or “Rishis,” whose voice is used to deliver Ayurvedic knowledge in the ancient texts of Ayurveda, these are referred to as the “Rishi principles.” Common research methodologies are examined for embodiment of these principles.

Shock Treatment: Using Immersive Digital Realism to Restage and Re-examine Milgram’s ‘Obedience to Authority’ Research

Haslam, S. Alexander; Reicher, Stephen D.; Millard, Kathryn
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 02/03/2015 EN
Relevância na Pesquisa
55.35%
Attempts to revisit Milgram’s ‘Obedience to Authority’ (OtA) paradigm present serious ethical challenges. In recent years new paradigms have been developed to circumvent these challenges but none involve using Milgram’s own procedures and asking naïve participants to deliver the maximum level of shock. This was achieved in the present research by using Immersive Digital Realism (IDR) to revisit the OtA paradigm. IDR is a dramatic method that involves a director collaborating with professional actors to develop characters, the strategic withholding of contextual information, and immersion in a real-world environment. 14 actors took part in an IDR study in which they were assigned to conditions that restaged Milgrams’s New Baseline (‘Coronary’) condition and four other variants. Post-experimental interviews also assessed participants’ identification with Experimenter and Learner. Participants’ behaviour closely resembled that observed in Milgram’s original research. In particular, this was evidenced by (a) all being willing to administer shocks greater than 150 volts, (b) near-universal refusal to continue after being told by the Experimenter that “you have no other choice, you must continue” (Milgram’s fourth prod and the one most resembling an order)...

Research Design and Statistical Methods in Indian Medical Journals: A Retrospective Survey

Hassan, Shabbeer; Yellur, Rajashree; Subramani, Pooventhan; Adiga, Poornima; Gokhale, Manoj; Iyer, Manasa S.; Mayya, Shreemathi S.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 09/04/2015 EN
Relevância na Pesquisa
55.36%
Good quality medical research generally requires not only an expertise in the chosen medical field of interest but also a sound knowledge of statistical methodology. The number of medical research articles which have been published in Indian medical journals has increased quite substantially in the past decade. The aim of this study was to collate all evidence on study design quality and statistical analyses used in selected leading Indian medical journals. Ten (10) leading Indian medical journals were selected based on impact factors and all original research articles published in 2003 (N = 588) and 2013 (N = 774) were categorized and reviewed. A validated checklist on study design, statistical analyses, results presentation, and interpretation was used for review and evaluation of the articles. Main outcomes considered in the present study were – study design types and their frequencies, error/defects proportion in study design, statistical analyses, and implementation of CONSORT checklist in RCT (randomized clinical trials). From 2003 to 2013: The proportion of erroneous statistical analyses did not decrease (χ2=0.592, Φ=0.027, p=0.4418), 25% (80/320) in 2003 compared to 22.6% (111/490) in 2013. Compared with 2003, significant improvement was seen in 2013; the proportion of papers using statistical tests increased significantly (χ2=26.96...

Understanding Original Antigenic Sin in Influenza with a Dynamical System

Pan, Keyao
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 29/08/2011 EN
Relevância na Pesquisa
45.42%
Original antigenic sin is the phenomenon in which prior exposure to an antigen leads to a subsequent suboptimal immune response to a related antigen. Immune memory normally allows for an improved and rapid response to antigens previously seen and is the mechanism by which vaccination works. I here develop a dynamical system model of the mechanism of original antigenic sin in influenza, clarifying and explaining the detailed spin-glass treatment of original antigenic sin. The dynamical system describes the viral load, the quantities of healthy and infected epithelial cells, the concentrations of naïve and memory antibodies, and the affinities of naïve and memory antibodies. I give explicit correspondences between the microscopic variables of the spin-glass model and those of the present dynamical system model. The dynamical system model reproduces the phenomenon of original antigenic sin and describes how a competition between different types of B cells compromises the overall effect of immune response. I illustrate the competition between the naïve and the memory antibodies as a function of the antigenic distance between the initial and subsequent antigens. The suboptimal immune response caused by original antigenic sin is observed when the host is exposed to an antigen which has intermediate antigenic distance to a second antigen previously recognized by the host's immune system.

Analysis of the structure of original research papers: an aid to writing original papers for publication.

Skelton, J
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /10/1994 EN
Relevância na Pesquisa
65.45%
BACKGROUND. An increasing number of people involved in medicine are under pressure to publish research, but there is little understanding of how to describe structured writing. AIM. This paper aims to describe the structure of original research papers published in the British Journal of General Practice with a view to providing insight into the nature of such analyses, and particularly to help researchers and trainers to write and teach writing more successfully. METHOD. A sample of 50 original papers published in the Journal between January 1989 and March 1993 were examined. The papers were subjected to a form of 'move structure analysis', a technique used in applied linguistics; move structure analysis assigns a tentative function to a piece of text, and identifies words/phrases associated with it. To be recognized, moves thus identified had to occur in the same section of the paper in 65% of the corpus, and/or appear in the same order relative to other moves in 50%. RESULTS. Fifteen moves were identified, four in the introduction, three in the method, and four each in the results and discussion. These moves functioned, for example in the discussion, to state limitations and defend successes; describe achievements; contextualize procedures and findings; and offer recommendations. Frequency scores ranged from 66% to 100%...

Quality of abstracts of original research articles in CMAJ in 1989.

Narine, L; Yee, D S; Einarson, T R; Ilersich, A L
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 15/02/1991 EN
Relevância na Pesquisa
65.47%
PURPOSE: To evaluate the quality of abstracts of original research articles. DESIGN: Blind, criterion-based survey. SAMPLE: Systematic sample of 33 abstracts of original research articles published in CMAJ in 1989. MEASUREMENT: The quality of abstracts was measured against a checklist of evaluation criteria, which were divided into eight categories. A score for each abstract was obtained by dividing the number of criteria present by the number applicable. The overall mean score was also determined. RESULTS: The overall mean score of abstract quality was 0.63 (standard deviation 0.13) out of 1. Of the abstracts reporting study design 56% did not include specific technical descriptors. About 52% did not explicitly describe the study variables. In describing subject selection 79% failed to use specific technical terms. Of the abstracts reporting results 66% did not provide appropriate supporting data. Of those that gave conclusions 86% did not address study limitations and 93% made no recommendations for future study. CONCLUSION: Most of the abstracts provided some information pertaining to each evaluation criterion but did not provide detail sufficient to enhance the reader's understanding of the article. On the basis of the study sample the abstracts need improvement in description of research design...

Experimental infection of a US spike-insertion deletion porcine epidemic diarrhea virus in conventional nursing piglets and cross-protection to the original US PEDV infection

Lin, Chun-Ming; Annamalai, Thavamathi; Liu, Xinsheng; Gao, Xiang; Lu, Zhongyan; El-Tholoth, Mohamed; Hu, Hui; Saif, Linda J.; Wang, Qiuhong
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.45%
Although the original US porcine epidemic diarrhea virus (PEDV) was confirmed as highly virulent by multiple studies, the virulence of spike-insertion deletion (S-INDEL) PEDV strains is undefined. In this study, 3–4 day-old conventional suckling piglets were inoculated with S-INDEL PEDV Iowa106 (4 pig litters) to study its virulence. Two litters of age-matched piglets were inoculated with either the original US PEDV PC21A or mock as positive and negative controls, respectively. Subsequently, all pigs were challenged with the original US PEDV PC21A on 21–29 days post-inoculation (dpi) to assess cross-protection. All S-INDEL Iowa106- and the original US PC21A-inoculated piglets developed diarrhea. However, the severity of clinical signs, mortality (0–75%) and fecal PEDV RNA shedding titers varied among the four S-INDEL Iowa106-inoculated litters. Compared with the original PC21A, piglets euthanized/died acutely from S-INDEL Iowa106 infection had relatively milder villous atrophy, lower antigen scores and more limited intestinal infection. Two of four S-INDEL Iowa106-infected sows and the original PC21A-infected sow showed anorexia and watery diarrhea for 1–4 days. After the original PC21A challenge, a subset (13/16) of S-INDEL Iowa106-inoculated piglets developed diarrhea...