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Paul Roddy 《Viruses》2014,6(10):3699-3718
The frequency and magnitude of recognized and declared filovirus-disease outbreaks have increased in recent years, while pathogenic filoviruses are potentially ubiquitous throughout sub-Saharan Africa. Meanwhile, the efficiency and effectiveness of filovirus-disease outbreak preparedness and response efforts are currently limited by inherent challenges and persistent shortcomings. This paper delineates some of these challenges and shortcomings and provides a proposal for enhancing future filovirus-disease outbreak preparedness and response. The proposal serves as a call for prompt action by the organizations that comprise filovirus-disease outbreak response teams, namely, Ministries of Health of outbreak-prone countries, the World Health Organization, Médecins Sans Frontières, the Centers for Disease Control and Prevention—Atlanta, and others.  相似文献   

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Sun Y  Han M  Kim C  Calvert JG  Yoo D 《Viruses》2012,4(4):424-446
Innate immunity is the first line of defense against viral infection, and in turn, viruses have evolved to evade host immune surveillance. As a result, viruses may persist in host and develop chronic infections. Type I interferons (IFN-α/β) are among the most potent antiviral cytokines triggered by viral infections. Porcine reproductive and respiratory syndrome (PRRS) is a disease of pigs that is characterized by negligible induction of type I IFNs and viral persistence for an extended period. For IFN production, RIG-I/MDA5 and JAK-STAT pathways are two major signaling pathways, and recent studies indicate that PRRS virus is armed to modulate type I IFN responses during infection. This review describes the viral strategies for modulation of type I IFN responses. At least three non-structural proteins (Nsp1, Nsp2, and Nsp11) and a structural protein (N nucleocapsid protein) have been identified and characterized to play roles in the IFN suppression and NF-κB pathways. Nsp's are early proteins while N is a late protein, suggesting that additional signaling pathways may be involved in addition to the IFN pathway. The understanding of molecular bases for virus-mediated modulation of host innate immune signaling will help us design new generation vaccines and control PRRS.  相似文献   

4.
Our study examined the efficacy of four treatment modalities in controlling hemorrhage and achieving hemodynamic stabilization in hemorrhagic shock: intravenous fluid replacement (IV); military antishock trousers used concomitantly with fluids (MAST); balloon occlusion at the level of the diaphragm with concomitant fluid replacement (balloon); and a combination of MAST inflation, balloon occlusion, and fluid resuscitation (MAST and balloon). Twenty-eight mongrel dogs were anesthetized, and the spleen was exposed and completely crushed. The abdomen was closed, and treatment was initiated and continued for four hours or until the dog died. For all conditions the hematocrit dropped during the course of the experiment; balloon occlusion was effective at slowing this drop (P less than .0001), but MAST had no statistically significant effect. Animals with balloons bled more slowly into the abdominal cavity than did animals in the other two groups (P less than .0001). MAST also were effective at slowing the bleeding (P less than .05). Of the balloon and the MAST and balloon dogs, all except one survived the entire four hours; this difference between balloon and nonballoon dogs is significant (P = .002). MAST did not have a statistically significant effect on survival. Perfusion pressure (PP) declined during the course of the experiment, and the balloon was effective at slowing this decline (P less than .0001); none of the other comparisons was statistically significant.  相似文献   

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Virus disease pandemics and epidemics that occur in the world’s staple food crops pose a major threat to global food security, especially in developing countries with tropical or subtropical climates. Moreover, this threat is escalating rapidly due to increasing difficulties in controlling virus diseases as climate change accelerates and the need to feed the burgeoning global population escalates. One of the main causes of these pandemics and epidemics is the introduction to a new continent of food crops domesticated elsewhere, and their subsequent invasion by damaging virus diseases they never encountered before. This review focusses on providing historical and up-to-date information about pandemics and major epidemics initiated by spillover of indigenous viruses from infected alternative hosts into introduced crops. This spillover requires new encounters at the managed and natural vegetation interface. The principal virus disease pandemic examples described are two (cassava mosaic, cassava brown streak) that threaten food security in sub-Saharan Africa (SSA), and one (tomato yellow leaf curl) doing so globally. A further example describes a virus disease pandemic threatening a major plantation crop producing a vital food export for West Africa (cacao swollen shoot). Also described are two examples of major virus disease epidemics that threaten SSA’s food security (rice yellow mottle, groundnut rosette). In addition, brief accounts are provided of two major maize virus disease epidemics (maize streak in SSA, maize rough dwarf in Mediterranean and Middle Eastern regions), a major rice disease epidemic (rice hoja blanca in the Americas), and damaging tomato tospovirus and begomovirus disease epidemics of tomato that impair food security in different world regions. For each pandemic or major epidemic, the factors involved in driving its initial emergence, and its subsequent increase in importance and geographical distribution, are explained. Finally, clarification is provided over what needs to be done globally to achieve effective management of severe virus disease pandemics and epidemics initiated by spillover events.  相似文献   

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AIM:To investigate whether routinely measured clinical variables could aid in differentiating intestinal tuberculosis(ITB)from Crohn’s disease(CD).METHODS:ITB and CD patients were prospectively included at four South Indian medical centres from October 2009 to July 2012.Routine investigations included case history,physical examination,blood biochemistry,ileocolonoscopy and histopathological examination of biopsies.Patients were followed-up after 2 and 6 mo of treatment.The diagnosis of ITB or CD was re-evaluated after 2 mo of antituberculous chemotherapy or immune suppressive therapy respectively,based on improvement in signs,symptoms and laboratory variables.This study was considered to be an exploratory analysis.Clinical,endoscopic and histopathological features recorded at the time of inclusion were subject to univariate analyses.Disease variables with sufficient number of recordings and P<0.05 were entered into logistic regression models,adjusted for known confounders.Finally,we calculated the odds ratios with respective confidence intervals for variables associated with either ITB or CD.RESULTS:This study included 38 ITB and 37 CD patients.Overall,ITB patients had the lowest body mass index(19.6 vs 22.7,P=0.01)and more commonly reported weight loss(73%vs 38%,P<0.01),watery diarrhoea(64%vs 33%,P=0.01)and rural domicile(58%vs 35%,P<0.05).Endoscopy typically showed mucosal nodularity(17/31 vs 2/37,P<0.01)and histopathology more frequently showed granulomas(10/30vs 2/35,P<0.01).The CD patients more frequently reported malaise(87%vs 64%,P=0.03),nausea(84%vs 56%,P=0.01),pain in the right lower abdominal quadrant on examination(90%vs 54%,P<0.01)and urban domicile(65%vs 42%,P<0.05).In CD,endoscopy typically showed involvement of multiple intestinal segments(27/37 vs 9/31,P<0.01).Using logistic regression analysis we found weight loss and nodularity of the mucosa were independently associated with ITB,with adjusted odds ratios of 8.6(95%CI:2.1-35.6)and 18.9(95%CI:3.5-102.8)respectively.Right lower abdominal quadrant pain on examination and involvement of≥3 intestinal segments were independently associated with CD with adjusted odds ratios of 10.1(95%CI:2.0-51.3)and 5.9(95%CI:1.7-20.6),respectively.CONCLUSION:Weight loss and mucosal nodularity were associated with ITB.Abdominal pain and excessive intestinal involvement were associated with CD.ITB and CD were equally common.  相似文献   

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Helicobacter pylori is a highly successful bacterium with a high global prevalence and the infection carries significant disease burden. It is also becoming increasingly difficult to eradicate and the main reason for this is growing primary antibiotic resistance rates in a world where antibiotics are frequently prescribed and readily available. Despite knowing much more about the bacterium since its discovery, such as its genomic makeup and pathogenesis, we have seen declining treatment success. Therefore, clinicians today must be prepared to face one, two or even multiple treatment failures, and should be equipped with sufficient knowledge to decide on the appropriate salvage therapy when this happens. This article discusses the factors contributing to treatment failure and reviews the second and thirdline treatment strategies that have been investigated. Established empiric second line treatment options include both bismuth based quadruple therapy and levofloxacin based triple therapy. Antibiotic testing is recommended prior to initiating third line treatment. In the event that antibiotic susceptibility testing is unavailable, third line treatment options include rifabutin, rifaximin and sitafloxacin based therapies.  相似文献   

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Barrett''s esophagus (BE) is a precursor for esophageal adenocarcinoma, which has an increased incidence rate over the last few decades. Its importance stems from the poor five-year survival of esophageal adenocarcinoma and current data that suggest a survival benefit when surveillance programs are implemented. In this review, we will cover the pathophysiology and natural history of BE and the different endoscopic findings. The prevalence of BE in different geographic areas and the incidence of high-grade dysplasia and adenocarcinoma in this patient population is reviewed. Recent recommendation for screening and surveillance of BE has been covered in this review as well as the efficacy of nonconventional imaging modalities and endoscopic ablation therapies.  相似文献   

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目的 调查湖南省岳阳市城区小学生血吸虫病防治知识、行为现状及健康教育需求情况,为制定科学有效的小学生血吸虫病健康教育方案提供参考依据。方法 采用分层整群抽样方法,抽取岳阳市城区洞庭湖湖畔学校和中心城区学校各2所,每所再从五、六年级分别抽取2个班的学生,通过调查问卷了解小学生血吸虫病相关知识、预防行为及健康教育需求,并进行统计分析。结果 共调查湖畔小学353人、中心城区小学363人,两组学校小学生年龄、性别、年级构成差异无统计学意义(t=-0.494,χ2性别=1.615,χ2年级=2.152;P均>0.05)。学生血吸虫病防治知识总知晓率为42.60%(305/716),其中,湖畔学校小学生血防知识知晓率(52.97%)高于中心城区(32.51%),差异有统计学意义(χ2=30.661,P<0.05);学生行为正确率为76.68%(549/716),血防知识知晓组行为正确率(81.31%)高于不知晓组(71.24%),差异有统计学意义(χ2=6.384,P<0.05)。学生血防知识主要来源于老师(47.49%);91.90%的学生愿意了解更多的血防知识,最喜欢的血防知识学习方式是参加课外活动(50.42%)。结论 岳阳市城区小学生的血防知识知晓率及行为正确率偏低,对血吸虫病防治健康教育需求较高。建议针对学生开展形式多样的血防健康教育,以增强学生的血吸虫病防护意识,提高自我防护能力。  相似文献   

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This paper compares different coating methods (in situ solid combustion, hybrid deposition, secondary growth on seed, suspension, double deposition of wet impregnation and suspension) to deposit Ce0.2Zr0.8O2 mixed oxides on cordierite substrates, for use as a three way catalyst. Among them, the double deposition was proven to be the most efficient one. The coated sample shows a BET (Brunauer–Emmett–Teller) surface area of 25 m2/g, combined with a dense and crack free surface. The catalyst with a layer of MnO2–NiO–Co3O4 mixed oxides on top of the Ce0.2Zr0.8O2/cordierite substrate prepared by this method exhibits good activity for the treatment of CO, NO and C3H6 in exhaust gases (CO conversion of 100% at 250 °C, C3H6 conversion of 100% at 400 °C and NO conversion of 40% at 400 °C).  相似文献   

13.
The risk of percutaneous chest tube thoracostomy for blunt thoracic trauma   总被引:1,自引:0,他引:1  
Analysis of 164 percutaneous chest tube thoracostomies performed as a standardized technical procedure in the management of 129 blunt trauma victims demonstrated an overall complication rate of 9.1% (15 of 164). Three complications (1.8%) were related to problems of insertion, and four (2.4%) represented the problem of pneumothorax after chest tube removal. The remaining eight complications (4.9%) were associated with positive bacterial cultures, two (1.2%) of which represented clinical empyema. Both cases of empyema had either prolonged chest tube placement (23 and 15 days) or multiple chest tubes (two and three) on the same side. Percutaneous chest tube thoracostomy remains an important facet in the management of certain types of blunt thoracic trauma. Associated risks can best be minimized with adherence to a standardized technique and management protocol.  相似文献   

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Various metal-β zeolites have been synthesized under similar ion-exchange conditions. During the exchange process, the nature and acid strength of the used cations modified the composition and textural properties as well as the Brönsted and Lewis acidity of the final materials. Zeolites exchanged with divalent cations showed a clear decrease of their surface Brönsted acidity and an increase of their Lewis acidity. All materials were active as catalysts for the transformation of acetone into hydrocarbons. Although the protonic zeolite was the most active in the acetone conversion (96.8% conversion), the metal-exchanged zeolites showed varied selectivities towards different products of the reaction. In particular, we found the Cu-β to have a considerable selectivity towards the production of isobutene from acetone (over 31% yield compared to 7.5% of the protonic zeolite). We propose different reactions mechanisms in order to explain the final product distributions.  相似文献   

15.
正肝豆状核变性(Wilson’s disease,WD)是常染色隐性遗传相关的铜代谢障碍性疾病,估计患病率为1:30000。该病是由于编码P型ATP酶的ATP7B基因突变,影响铜的分泌及排泄所致铜沉积。儿童肝豆状核变性的临床表现可以从无症状肝脏疾病到肝硬化或者肝衰竭,但是神经精神症状却非常少见。常规的检测方法包括血清铜蓝蛋白、24 h尿铜。最终的诊断需要基于症状、评估铜代谢的生化学检  相似文献   

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The objectives of this study were to compare the efficacy and tolerability of twice-daily formoterol dry powder 12 µg and 24 µg (Foradil) delivered via Aerolizer inhaler with four times daily albuterol (salbutamol) 180 µg delivered via metered dose inhaler (MDI) and placebo. A total of 554 adolescents and adults (ages 12-75 years) with mild-to-moderate asthma were randomized to this 12-week, multicenter, double-blind, double-dummy, placebo-controlled, parallel-group study. Twelve-hour spirometry measurements were taken at weeks 0, 4, 8, and 12. A total of 484 patients completed the study (122, 116, 127, and 119 given formoterol 12 µg, formoterol 24 µg, albuterol, and placebo, respectively). For the primary efficacy variable, the forced expiratory volume in 1 second (FEV1), both formoterol 12 µg and 24 µg were statistically superior to placebo at all time points on all test days (p ≤ 0.017) and to albuterol at most time points on all test days (p ≤ 0.001). The onset of improvement in FEV1 was rapid, with 15% increase within 5 min in 57%, 71%, and 65% of formoterol 12 µg, formoterol 24 µg, and albuterol patients, respectively. Formoterol was also superior to placebo and albuterol in terms of secondary efficacy variables: FEV1 area under the curve, percentage of predicted FEV1, forced vital capacity and forced expiratory flow, asthma symptom scores, and peak expiratory flows. In conclusion, both formoterol doses were superior to placebo in all lung function measurements. Overall, compared with albuterol, both formoterol doses produced superior bronchodilation. Formoterol and albuterol were safe and well-tolerated.  相似文献   

17.
Metabolic syndrome (MS) can be defined as a group of signs that increases the risk of developing type 2 diabetes mellitus (DM2). These signs include obesity, hyperinsulinemia and insulin resistance. We are interested in the mechanisms that trigger hyperinsulinemia as a step to understand how β cells fail in DM2. Pancreatic β cells secrete insulin in response to glucose variations in the extracellular medium. When they are chronically over-stimulated, hyperinsulinemia is observed; but then, with time, they become incapable of maintaining normal glucose levels, giving rise to DM2. A chronic high sucrose diet for two months induces MS in adult male Wistar rats. In the present article, we analyzed the effect of the internal environment of rats with MS, on the activity of ATP-sensitive potassium channels (KATP) and calcium currents of pancreatic β cells. After 24 weeks of treatment with 20% sucrose in their drinking water, rats showed central obesity, hyperinsulinemia and insulin resistance, and their systolic blood pressure and triglycerides plasma levels increased. These signs indicate the onset of MS. KATP channels in isolated patches of β cells from MS rats, had an increased sensitivity to ATP with respect to controls. Moreover, the macroscopic calcium currents, show increased variability compared with cells from control individuals. These results demonstrate that regardless of genetic background, a high sucrose diet leads to the development of MS. The observed changes in ionic channels can partially explain the increase in insulin secretion in MS rats. However, some β cells showed smaller calcium currents. These cells may represent a β cell subpopulation as it becomes exhausted by the long-term high sucrose diet.  相似文献   

18.
Type 2 diabetes constitutes a major health risk in the United States, with over 20% of individuals over the age of 60 currently suffering from this disease and an additional 1.5 million new cases diagnosed in patients over 20 years of age in 2005. Similarly, Alzheimer''s disease represents a major risk to the aging population, with recent statistics estimating up to 16 million people diagnosed by 2050 in the United States alone. As type 2 diabetes and Alzheimer''s disease are now recognized as members of the broader class of amyloid diseases and because the pathologies of disease progression between these indications is similar, common strategies focused on the design of next-generation therapeutics can be envisioned and are discussed herein.  相似文献   

19.
A case of massive digoxin ingestion with multiple arrhythmias, consisting of high grade A-V block and ventricular ectopy not responsive to lidocaine, is described. The arrhythmias ceased following administration of digoxin-specific Fab fragments. The patient improved and was transferred to the psychiatric unit.  相似文献   

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ObjectiveThe use of coronavirus disease 2019 (COVID‐19) serological testing to diagnose acute infection or determine population seroprevalence relies on understanding assay accuracy during early infection. We aimed to evaluate the diagnostic performance of serological testing in COVID‐19 by providing summary sensitivity and specificity estimates with time from symptom onset.MethodsA systematic search of Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL) and PubMed was performed up to May 13, 2020. All English language, original peer‐reviewed publications reporting the diagnostic performance of serological testing vis‐à‐vis virologically confirmed SARS‐CoV‐2 infection were included.ResultsOur search yielded 599 unique publications. A total of 39 publications reporting 11 516 samples from 8872 human participants met eligibility criteria for inclusion in our study. Pooled percentages of IgM and IgG seroconversion by Day 7, 14, 21, 28 and after Day 28 were 37.5%, 73.3%, 81.3%, 72.3% and 73.3%, and 35.4%, 80.6%, 93.3%, 84.4% and 98.9%, respectively. By Day 21, summary estimate of IgM sensitivity was 0.872 (95% CI: 0.784‐0.928) and specificity 0.973 (95% CI: 0.938‐0.988), while IgG sensitivity was 0.913 (95% CI: 0.823‐0.959) and specificity 0.960 (95% CI: 0.919‐0.980). On meta‐regression, IgM and IgG test accuracy was significantly higher at Day 14 using enzyme‐linked immunosorbent assay (ELISA) compared to other methods.ConclusionsSerological assays offer imperfect sensitivity for the diagnosis of acute SARS‐CoV‐2 infection. Estimates of population seroprevalence during or shortly after an outbreak will need to adjust for the delay between infection, symptom onset and seroconversion.  相似文献   

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