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1.
The effect of temperature on embryonic development and reproduction ofLymnaea luteola was studied. This snail did not develop completely and failed to reproduce at 15 °C and 40 °C. The temperature range of 25 °C–35 °C was observed to be optimum for development and reproduction of this snail. The utility of this study in predicting seasonal fluctuations of snail population in nature is discussed.  相似文献   
2.
Endocytosis is the fundamental uptake process through which cells internalize extracellular materials and species. Neurodegenerative diseases (NDs) are characterized by a progressive accumulation of intrinsically disordered protein species, leading to neuronal death. Misfolding in many proteins leads to various NDs such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS) and other disorders. Despite the significance of disordered protein species in neurodegeneration, their spread between cells and the cellular uptake of extracellular species is not entirely understood. This review discusses the major internalization mechanisms of the different conformer species of these proteins and their endocytic mechanisms. We briefly introduce the broad types of endocytic mechanisms found in cells and then summarize what is known about the endocytosis of monomeric, oligomeric and aggregated conformations of tau, Aβ, α-Syn, Huntingtin, Prions, SOD1, TDP-43 and other proteins associated with neurodegeneration. We also highlight the key players involved in internalizing these disordered proteins and the several techniques and approaches to identify their endocytic mechanisms. Finally, we discuss the obstacles involved in studying the endocytosis of these protein species and the need to develop better techniques to elucidate the uptake mechanisms of a particular disordered protein species.  相似文献   
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Molecular Biology Reports - A 26-year-old male had a history of frequent bowel movements, mushy stool with mucus and loss of 25 kg body weight in 6 months was diagnosed as a case...  相似文献   
5.

Background

Chikungunya virus (CHIKV) has reemerged as a life threatening pathogen and caused large epidemics in several countries. So far, no licensed vaccine or effective antivirals are available and the treatment remains symptomatic. In this context, development of effective and safe prophylactics and therapeutics assumes priority.

Methods

We evaluated the efficacy of the siRNAs against ns1 and E2 genes of CHIKV both in vitro and in vivo. Four siRNAs each, targeting the E2 (Chik-1 to Chik-4) and ns1 (Chik-5 to Chik-8) genes were designed and evaluated for efficiency in inhibiting CHIKV growth in vitro and in vivo. Chik-1 and Chik-5 siRNAs were effective in controlling CHIKV replication in vitro as assessed by real time PCR, IFA and plaque assay.

Conclusions

CHIKV replication was completely inhibited in the virus-infected mice when administered 72 hours post infection. The combination of Chik-1 and Chik-5 siRNAs exhibited additive effect leading to early and complete inhibition of virus replication. These findings suggest that RNAi capable of inhibiting CHIKV growth might constitute a new therapeutic strategy for controlling CHIKV infection and transmission.  相似文献   
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Aims and methods It is now well established that antipsychotic medications are associated with adverse effects such as metabolic dysfunction, hyperprolactinaemia and cardiac arrhythmias. We completed an audit cycle between 2008 and 2010 to assess whether the implementation of a high-visibility prompt and an educational programme would improve monitoring rates among patients prescribed regular antipsychotics admitted to a 59-bedded psychiatric hospital in West Sussex.Results There was an improvement in monitoring rates for most audit standards. The greatest improvement was seen in measurement of random plasma glucose and cholesterol levels. Rates improved irrespective of the risk of metabolic dysfunction. However, prolactin measurement remained static and the ECG recording deteriorated.Clinical implications There appears to be a growing awareness of the need to screen for metabolic dysfunction among patients prescribed regular antipsychotic medication. A high-visibility prompt and educational programme helps to increase monitoring rates. However, more needs to be done to improve the mortality and morbidity rates among this patient subpopulation.  相似文献   
8.

Background

We studied the transmission of rotavirus infection in households in peri-urban Ecuador in the vaccination era.

Methods

Stool samples were collected from household contacts of child rotavirus cases, diarrhea controls and healthy controls following presentation of the index child to health facilities. Rotavirus infection status of contacts was determined by RT-qPCR. We examined factors associated with transmissibility (index-case characteristics) and susceptibility (household-contact characteristics).

Results

Amongst cases, diarrhea controls and healthy control household contacts, infection attack rates (iAR) were 55%, 8% and 2%, (n = 137, 130, 137) respectively. iARs were higher from index cases with vomiting, and amongst siblings. Disease ARs were higher when the index child was <18 months and had vomiting, with household contact <10 years and those sharing a room with the index case being more susceptible. We found no evidence of asymptomatic infections leading to disease transmission.

Conclusion

Transmission rates of rotavirus are high in households with an infected child, while background infections are rare. We have identified factors associated with transmission (vomiting/young age of index case) and susceptibility (young age/sharing a room/being a sibling of the index case). Vaccination may lead to indirect benefits by averting episodes or reducing symptoms in vaccinees.  相似文献   
9.

Background

Postlicensure data has identified a causal link between rotavirus vaccines and intussusception in some settings. As rotavirus vaccines are introduced globally, monitoring intussusception will be crucial for ensuring safety of the vaccine programs.

Methods

To obtain updated information on background rates and clinical management of intussusception, we reviewed studies of intussusception in children <18 years of age published since 2002. We assessed the incidence of intussusception by month of life among children <1 year of age, seasonality, method of diagnosis, treatment, and case-fatality.

Findings

We identified 82 studies from North America, Asia, Europe, Oceania, Africa, Eastern Mediterranean, and Central & South America that reported a total of 44,454 intussusception events. The mean incidence of intussusception was 74 per 100,000 (range: 9–328) among children <1 year of age, with peak incidence among infants 5–7 months of age. No seasonal patterns were observed. A radiographic modality was used to diagnose intussusception in over 95% of the cases in all regions except Africa where clinical findings or surgery were used in 65% of the cases. Surgical rates were substantially higher in Africa (77%) and Central and South America (86%) compared to other regions (13–29%). Case-fatality also was higher in Africa (9%) compared to other regions (<1%). The primary limitation of this review relates to the heterogeneity in intussusception surveillance across different regions.

Conclusion

This review of the intussusception literature from the past decade provides pertinent information that should facilitate implementation of intussusception surveillance for monitoring the postlicensure safety of rotavirus vaccines.  相似文献   
10.
Globally, norovirus is associated with approximately one-fifth of all diarrhea cases, with similar prevalence in both children and adults, and is estimated to cause over 200,000 deaths annually in developing countries. Norovirus is an important pathogen in a number of high-priority domains: it is the most common cause of diarrheal episodes globally, the principal cause of foodborne disease outbreaks in the United States, a key health care–acquired infection, a common cause of travel-associated diarrhea, and a bane for deployed military troops. Partly as a result of this ubiquity and burden across a range of different populations, identifying target groups and strategies for intervention has been challenging. And, on top of the breadth of this public health problem, there remain important gaps in scientific knowledge regarding norovirus, especially with respect to disease in low-income settings.Many pathogens can cause acute gastroenteritis. Historically, rotavirus was the most common cause of severe disease in young children globally. Now, vaccines are available for rotavirus and are universally recommended by the World Health Organization. In countries with effective rotavirus vaccination programs, disease due to that pathogen has decreased markedly, but norovirus persists and is now the most common cause of pediatric gastroenteritis requiring medical attention. However, the data supporting the precise role of norovirus in low- and middle-income settings are sparse. With vaccines in the pipeline, addressing these and other important knowledge gaps is increasingly pressing.We assembled an expert group to assess the evidence for the global burden of norovirus and to consider the prospects for norovirus vaccine development. The group assessed the evidence in the areas of burden of disease, epidemiology, diagnostics, disease attribution, acquired immunity, and innate susceptibility, and the group considered how to bring norovirus vaccines from their current state of development to a viable product that will benefit global health.

Summary Points

  • Diagnostic improvements have fundamentally changed our understanding of norovirus. The current evidence suggests that disease burden of norovirus is high, second only to rotavirus as a cause of severe acute gastroenteritis in children in developed countries, and that it is a key cause of diarrhea-associated morbidity and mortality worldwide.
  • Young children experience the highest incidence of disease; severe outcomes are most common among young children and the elderly.
  • Immunity is of limited duration and is strain- or genotype-specific, with little or no protection conferred across genogroups.
  • Innate susceptibility to noroviruses is determined by the host’s genetics of glycan expression; individuals with a functional FUT2 gene (known as secretors) have greater susceptibility to certain common viruses.
  • Recent progress has been made in the development of in vitro cell culture for norovirus as well as in the identification of candidate immune correlates of protection.
  • Norovirus vaccines are steadily moving through the development pipeline. All of these products are based on the production of virus like particles (VLPs) or P particle subunit in expression systems. Initial human challenge studies have demonstrated safety, immunogenicity, and efficacy.
  • One of the challenges for developing targeted interventions, including a norovirus vaccine, is that many distinct population groups, based on demographics (e.g., children, elderly) or risk (e.g., food handlers, military, travelers, health care workers), are affected.
  相似文献   
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