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1.
Restoration of pathogen-specific immunity as a result of highly active antiretroviral therapy or reduction of immunosuppression in solid-organ transplant recipients can result in a destructive inflammatory response known as the immune reconstitution inflammatory syndrome (IRIS). Though immune reconstitution disorders can occur in the context of a number of infectious and neoplastic processes, IRIS associated with invasive mycoses, in particular cryptococcosis, is a highly prevalent and morbid entity worldwide. Recent consensus definitions and prospective analyses of cryptococcal IRIS, with particular attention to baseline clinical features, serum and cerebrospinal fluid biomarkers, and the evolution of these over time in individual patients have provided critical insights into pathogenesis. This review focuses on the current understanding of IRIS in the context of opportunistic mycoses, with particular attention to Cryptococcus infection, and discusses the basis for this understanding, including biomarkers as clues to pathogenesis and aids in diagnosis and novel approaches to prevention and management.  相似文献   

2.
The “criticality” of the various elements used in modern technologies is a topic of increasing interest, with groups from governments, consultancies, and academic institutions developing a variety of methodologies and using them to make assessments. Other groups from similar organizations are studying the methodologies that generate these assessments. Here, we analyze the different types of studies, review issues of methodology, and comment on features of nine different studies published between 2008 and mid‐2014. From these studies, we derive lists of problematic, debatable, and desirable aspects of criticality studies. We emphasize that the criticality of an element can vary depending on the target organization and that, because criticality is a dynamic state, it must be periodically re‐evaluated. There is substantial value to be derived if a more uniform methodology could be developed. We discuss how a harmonized methodological framework might be achieved and what its benefits could be. Putting into place such a structure for collaborative and publicly available criticality determinations would be very likely to better serve the present and future needs of corporations and governments than is the case at present, where different methodologies generate different results.  相似文献   

3.
Qβ replicase (RNA-directed RNA polymerase of bacteriophage Qβ) has an unsurpassed capacity to amplify polynucleotides in vitro. In 1986, the Group of Viral RNA Biochemistry was organized at the Institute of Protein Research in order to exploit this property for the synthesis of messenger RNAs to be used in cell-free translation systems. Although the task has not been implemented in full, this work has led to a number of unexpected important results including uncovering the nature of the “template-free” RNA synthesis by Qβ replicase, discovering the ability of RNA molecules for spontaneous recombination, revealing the unusual mechanism Qβ replicase uses to discriminate between its proper and improper templates, and discovering a new function of the largest ribosomal protein S1, that is also one of the replicase subunits. Finally, our work resulted in the invention of the molecular colonies technique that has become the basis for the next generation sequencing methods and provided a new insight into the origin of life. However, Qβ replicase has not yet revealed all its secrets, and its studies promise further interesting findings.  相似文献   

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Antibiotics are enormously important for the humane and efficient production of food animals. These benefits are somewhat offset by the human and animal health antibiotic resistance risks posed by their use in animals. This article provides an overview of what we have learned about antibiotic resistance as an issue in animal agriculture and where that knowledge could lead us in the future. To preserve the effectiveness of antibiotics, more action is needed to ensure their prudent use, particularly in the case of antibiotic growth promoters and antibiotics deemed critically important for human and animal health.  相似文献   

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Background

Due to an ageing population and demographic changes worldwide, a higher prevalence of heart disease is forecasted, which causes an even higher demand for cardiac implants in future. The increasing high incidence of clinical adverse events attributed especially to high-risk medical devices has led an advocated change from many stakeholders. This holds especially true for devices like cardiac implants, with their high-risk nature and high complication rates associated with considerable mortality, due to their frequent use in older populations with frequent co-morbidities. To ensure patients’ safety, the objective of this study is to analyze different cardiac implants recall reasons and different recall systems, based on an overview of the recalls of cardiac implant medical devices in the last decade. On the basis of the results from this structured analysis, this study provides recommendations on how to avoid such recalls from a manufacturer perspective, as well as how to timely react to an adverse event from a post-surveillance system perspective.

Methods and Findings

A systematic search of cardiac implant recalls information has been performed in the PubMed, ScienceDirect and Scopus databases, as well as data sources in regulatory authorities from 193 UN Member States. Data has been extracted for the years 2004-2014 with the following criteria applied: cardiac implant medical device recalls and reasons for recall, associated harm or risk to patients. From the data sources described above, eleven regulatory authorities and 103 recall reports have been included in this study. The largest cardiac implant categories include ICDs 40.8%, pacemakers 14.5% and stents 14.5%. Regarding the recall reasons, the majority of reports were related to device battery problems (33.0%) and incorrect therapy delivery (31.1%). From a total of 103 recall reports, five reported death and serious injuries. Our review highlights weaknesses in the current cardiac implant recall system, including data reporting and management issues and provides recommendations for the improvement of safety information and management.

Conclusion

Due to the mortality associated with the nature of cardiac implants, the traceability and transparency of safety hazards information is crucial. By a structured analysis of recall reasons and their efficient management, important knowledge is gained to inform an effective safety-reporting system for monitoring the safety of cardiac implanted patients, ideally by building up cardiac implant registries worldwide in the future.  相似文献   

9.
Tropical reefs shelter one quarter to one third of all marine species but one third of the coral species that construct reefs are now at risk of extinction. Because traditional methods for assessing reef diversity are extremely time consuming, taxonomic expertise for many groups is lacking, and marine organisms are thought to be less vulnerable to extinction, most discussions of reef conservation focus on maintenance of ecosystem services rather than biodiversity loss. In this study involving the three major oceans with reef growth, we provide new biodiversity estimates based on quantitative sampling and DNA barcoding. We focus on crustaceans, which are the second most diverse group of marine metazoans. We show exceptionally high numbers of crustacean species associated with coral reefs relative to sampling effort (525 species from a combined, globally distributed sample area of 6.3 m(2)). The high prevalence of rare species (38% encountered only once), the low level of spatial overlap (81% found in only one locality) and the biogeographic patterns of diversity detected (Indo-West Pacific>Central Pacific>Caribbean) are consistent with results from traditional survey methods, making this approach a reliable and efficient method for assessing and monitoring biodiversity. The finding of such large numbers of species in a small total area suggests that coral reef diversity is seriously under-detected using traditional survey methods, and by implication, underestimated.  相似文献   

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Candidate gene and genome-wide association studies have led to the discovery of nine loci involved in Mendelian forms of obesity and 58 loci contributing to polygenic obesity. These loci explain a small fraction of the heritability for obesity and many genes remain to be discovered. However, efforts in obesity gene identification greatly modified our understanding of this disorder. In this review, we propose an overlook of major lessons learned from 15 years of research in the field of genetics and obesity. We comment on the existence of the genetic continuum between monogenic and polygenic forms of obesity that pinpoints the role of genes involved in the central regulation of food intake and genetic predisposition to obesity. We explain how the identification of novel obesity predisposing genes has clarified unsuspected biological pathways involved in the control of energy balance that have helped to understand past human history and to explore causality in epidemiology. We provide evidence that obesity predisposing genes interact with the environment and influence the response to treatment relevant to disease prediction.  相似文献   

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Mycopathologia - The fungus Talaromyces marneffei was described by Professor Gabriel Segretain in 1959, originally as a member of the genus Penicillium. As early as 60 years ago, its...  相似文献   

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Importance

Trauma is a global disease and is among the leading causes of disability in the world. The importance of outcome beyond trauma survival has been recognised over the last decade. Despite this there is no internationally agreed approach for assessment of health outcome and rehabilitation of trauma patients.

Objective

To systematically examine to what extent outcomes measures evaluate health outcomes in patients with major trauma.

Data Sources

MEDLINE, EMBASE, and CINAHL (from 2006–2012) were searched for studies evaluating health outcome after traumatic injuries.

Study selection and data extraction

Studies of adult patients with injuries involving at least two body areas or organ systems were included. Information on study design, outcome measures used, sample size and outcomes were extracted. The World Health Organisation International Classification of Function, Disability and Health (ICF) were used to evaluate to what extent outcome measures captured health impacts.

Results

34 studies from 755 studies were included in the review. 38 outcome measures were identified. 21 outcome measures were used only once and only five were used in three or more studies. Only 6% of all possible health impacts were captured. Concepts related to activity and participation were the most represented but still only captured 12% of all possible concepts in this domain. Measures performed very poorly in capturing concepts related to body function (5%), functional activities (11%) and environmental factors (2%).

Conclusion

Outcome measures used in major trauma capture only a small proportion of health impacts. There is no inclusive classification for measuring disability or health outcome following trauma. The ICF may provide a useful framework for the development of a comprehensive health outcome measure for trauma care.  相似文献   

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Background and Objective

Bacterial vaginosis (BV) is the most common vaginal disorder, characterized by depletion of the normal lactobacillus-dominant microbiota and overgrowth of commensal anaerobic bacteria. This study aimed to investigate the composition of the vaginal microbiota in women of reproductive age (healthy women and women with BV), with the view of developing molecular criteria for BV diagnosis.

Materials and Methods

Vaginal samples from 163 women (79 control, 73 BV and 11 intermediate (Lactobacillary grade II flora) cases) were analyzed using 454 pyrosequencing of the hypervariable regions V3–V4 of the 16S rRNA gene and 16 quantitative bacterial species/genus-specific real-time PCR assays. Sensitivities and specificities of potential BV markers were computed using the Amsel criteria as reference standard for BV. The use of quantitative thresholds for prediction of BV, determined for both relative abundance measured with 454 pyrosequencing and bacterial load measured with qPCR, was evaluated.

Results

Relative to the healthy women, the BV patients had in their vaginal microbiota significantly higher prevalence, loads and relative abundances of the majority of BV associated bacteria. However, only Gardnerella vaginalis, Atopobium vaginae, Eggerthella, Prevotella, BVAB2 and Megasphaera type 1 detected at or above optimal thresholds were highly predictable for BV, with the best diagnostic accuracy shown for A. vaginae. The depletion of Lactobacillus species combined with the presence of either G. vaginalis or A. vaginae at diagnostic levels was a highly accurate BV predictor.

Conclusions

Quantitative determination of the presence of G. vaginalis, A. vaginae, Eggerthella, Prevotella, BVAB2 and Megasphaera type 1 as well as the depletion of Lactobacillus was highly accurate for BV diagnosis. Measurements of abundance of normal and BV microbiota relative to total bacteria in vaginal fluid may provide more accurate BV diagnosis, and be used for test-of-cure, rather than qualitative detection or absolute counts of BV related microorganisms.  相似文献   

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Insects that undergo complete metamorphosis experience enormous changes in both morphology and lifestyle. The current study examines whether larval experience can persist through pupation into adulthood in Lepidoptera, and assesses two possible mechanisms that could underlie such behavior: exposure of emerging adults to chemicals from the larval environment, or associative learning transferred to adulthood via maintenance of intact synaptic connections. Fifth instar Manduca sexta caterpillars received an electrical shock associatively paired with a specific odor in order to create a conditioned odor aversion, and were assayed for learning in a Y choice apparatus as larvae and again as adult moths. We show that larvae learned to avoid the training odor, and that this aversion was still present in the adults. The adult aversion did not result from carryover of chemicals from the larval environment, as neither applying odorants to naïve pupae nor washing the pupae of trained caterpillars resulted in a change in behavior. In addition, we report that larvae trained at third instar still showed odor aversion after two molts, as fifth instars, but did not avoid the odor as adults, consistent with the idea that post-metamorphic recall involves regions of the brain that are not produced until later in larval development. The present study, the first to demonstrate conclusively that associative memory survives metamorphosis in Lepidoptera, provokes intriguing new questions about the organization and persistence of the central nervous system during metamorphosis. Our results have both ecological and evolutionary implications, as retention of memory through metamorphosis could influence host choice by polyphagous insects, shape habitat selection, and lead to eventual sympatric speciation.  相似文献   

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JM Haugh 《Biophysical journal》2012,102(9):2003-2011
Engineered protein biosensors, such as those based on Förster resonance energy transfer, membrane translocation, or solvatochromic shift, are being used in combination with live-cell fluorescence microscopy to reveal kinetics and spatial localization of intracellular processes as they occur. Progress in the application of this approach has been steady, yet its general suitability for quantitative measurements remains unclear. To address the pitfalls of the biosensor approach in quantitative terms, simple reaction-diffusion models were analyzed. The analysis shows that although high-affinity molecular recognition allows robust detection of the fluorescence readout, either of two detrimental effects is fostered. Binding of an intramolecular biosensor or of a relatively abundant intermolecular biosensor introduces observer effects in which the dynamics of the target molecule under study are significantly perturbed, whereas binding of a sparingly expressed intermolecular biosensor is subject to a saturation effect, where the pool of unbound biosensor is significantly depleted. The analysis explores how these effects are manifest in the kinetics and spatial gradients of the biosensor-target complex. A sobering insight emerges: the observer or saturation effect is always significant; the question is whether or not it can be tolerated or accounted for. The challenge in managing the adverse effects is that specification of the biosensor-target affinity to within a certain order of magnitude is required.  相似文献   

18.
Since 1984, we have diagnosed at the La Paz University Hospital, Madrid, Spain, 41 patients with hypoxanthine phosphoribosyltransferase (HPRT) activity deficiency. These patients belonged to 34 families. We have also performed molecular and enzymatic diagnosis in three patients from India, one from Belgium, and three from Colombia. About 1/3 of these patients were followed up at La Paz University Hospital at least every year. This fact has allowed us to examine the complete spectrum of HPRT deficiency as well as to perform a more accurate diagnosis and treatment. In the present review, we also summarized our studies on the basis of physiopathology of the neurological manifestation of Lesch Nyhan disease (LND).  相似文献   

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Background

The human gut microbiota has profound influence on host metabolism and immunity. This study characterized the fecal microbiota in patients with nonalcoholic steatohepatitis (NASH). The relationship between microbiota changes and changes in hepatic steatosis was also studied.

Methods

Fecal microbiota of histology-proven NASH patients and healthy controls was analyzed by 16S ribosomal RNA pyrosequencing. NASH patients were from a previously reported randomized trial on probiotic treatment. Proton-magnetic resonance spectroscopy was performed to monitor changes in intrahepatic triglyceride content (IHTG).

Results

A total of 420,344 16S sequences with acceptable quality were obtained from 16 NASH patients and 22 controls. NASH patients had lower fecal abundance of Faecalibacterium and Anaerosporobacter but higher abundance of Parabacteroides and Allisonella. Partial least-square discriminant analysis yielded a model of 10 genera that discriminated NASH patients from controls. At month 6, 6 of 7 patients in the probiotic group and 4 of 9 patients in the usual care group had improvement in IHTG (P = 0.15). Improvement in IHTG was associated with a reduction in the abundance of Firmicutes (R2 = 0.4820, P = 0.0028) and increase in Bacteroidetes (R2 = 0.4366, P = 0.0053). This was accompanied by corresponding changes at the class, order and genus levels. In contrast, bacterial biodiversity did not differ between NASH patients and controls, and did not change with probiotic treatment.

Conclusions

NASH patients have fecal dysbiosis, and changes in microbiota correlate with improvement in hepatic steatosis. Further studies are required to investigate the mechanism underlying the interaction between gut microbes and the liver.  相似文献   

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