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81.
Retinitis pigmentosa (RP) is a group of retinal dystrophies characterised primarily by rod photoreceptor cell degeneration. Exhibiting great clinical and genetic heterogeneity, RP be inherited as an autosomal dominant (ad) and recessive (ar), X-linked (xl) and digenic disorder. RP25 , a locus for arRP, was mapped to chromosome 6p12.1-q14.1 where several retinal dystrophy loci are located. A gene expressed in the retina, FAM46A , mapped within the RP25 locus, and computational data revealed its involvement in retinal signalling pathways. Therefore, we chose to perform molecular evaluation of this gene as a good candidate in arRP families linked to the RP25 interval. A comprehensive bioinformatic and retinal tissue expression characterisation of FAM46A was performed, together with mutation screening of seven RP25 families.
Herein we present 4 novel sequence variants, of which one is a novel deletion within a low complexity region close to the initiation codon of FAM46A . Furthermore, we have characterised for the first time a coding tandem variation in the Caucasian population.
This study reports on bioinformatic and moleculardata for the FAM46A gene that may give a wider insight into the putative function of this gene and its pathologic relevance to RP25 and other retinal diseases mapping within the 6q chromosomal interval.  相似文献   
82.
Serine/threonine phosphorylation of the nonstructural protein 5 (NS5) is conserved feature of flaviviruses, but the kinase(s) responsible and function(s) remain unknown. Mass spectrometry was used to characterize phosphorylated residues of yellow fever virus (YFV) NS5 expressed in mammalian cells. Multiple different phosphopeptides were detected. Mutational and additional mass spectrometry data implicated serine 56 (S56), a conserved residue near the active site in the NS5 methyltransferase domain, as one of the phosphorylation sites. Methyltransferase activity is required to form a methylated RNA cap structure and for translation of the YFV polyprotein. We show the 2′-O methylation reaction requires the hydroxyl side chain of S56, and replacement with a negative charge inhibits enzymatic activity. Furthermore mutational alteration of S56, S56A or S56D, prevents amplification in a viral replicon system. Collectively our data suggest phosphorylation of NS5 S56 may act to shut down capping in the viral life cycle.  相似文献   
83.
Activation-induced deaminase (AID) is the master regulator of class switch recombination (CSR) and somatic hypermutation (SHM), but the mechanisms regulating AID function are obscure. The differential pattern of switch plasmid activity in three IgM(+)/AID(+) and two IgG(+)/AID(+) B cell lines prompted an analysis of global gene expression to discover the origin of these cells. Gene profiling suggested that the IgG(+)/AID(+) B cell lines derived from germinal center B cells. Analysis of SHM potential demonstrates that the IgVkappa domains are inducibly diversified at high rate during in vitro culture. The mutation spectra focused to A:T base pairs, revealing a component of the hypermutation program that occurs preferentially during phase 2 of SHM. The A:T error spectra were analyzed and were not characteristic of polymerase eta activity. A differential pattern of three consensus motifs used for A:T base substitutions was observed in WT and Poleta-, Msh2- and Msh6-deficient B cells. Strikingly, mutations in our B cell lines recapitulated the mutable motif profile for Poleta and Msh2 deficiency, respectively, and suggest that an additional pathway for the generation of A:T mutations in SHM is conserved in mouse and human.  相似文献   
84.
Although platelets induce lung inflammation, leading to acute lung injury (ALI), the extent of platelet-endothelial cell (EC) interactions remains poorly understood. Here, in a ventilation-stress model of lung inflammation, we show that platelet-EC interactions are important. We obtained freshly isolated lung endothelial cells (FLECs) from isolated, blood-perfused rat lungs exposed to ventilation at low tidal volume (LV) or stress-inducing high tidal volume (HV). Immunofluorescence and immunoprecipitation studies revealed HV-induced increases in cell-surface von Willebrand factor (vWf) expression on FLEC. This increased expression was inhibited by platelet removal from the lung perfusion and by including a P-selectin-blocking antibody in the lung perfusion. The expression was also blocked in lungs from P-selectin knockout (P sel(-/-)) mice perfused with autologous blood, but not with heterologous wild-type blood containing P-selectin-expressing platelets. These findings indicate that in ventilation stress, platelets transfer vWf to the EC surface and that platelet P-selectin plays a critical role in this transfer. Further evidence for such intercellular transfers was the HV-induced FLEC expressions of platelet glycoprotein 1b and of platelet P-selectin. We conclude that in ventilation stress, platelets deposit leukocyte- and platelet-binding proteins on the EC surface, thereby establishing the proinflammatory phenotype of the vascular lining.  相似文献   
85.
Summary. Long electropherotype with Subgroup I specificity is a common feature of animal rotaviruses. In an epidemic of infantile gastroenteritis in Manipur, India, long but SG I strains predominated in the outbreak in the year 1987–88. One such strain isolated from that region, following the outbreak had G9P [19] specificity. As this is a rare combination, the gene sequences encoding VP4, VP6, VP7, NSP1, NSP2, NSP3, NSP4 and NSP5 of this strain were analyzed. All these genes except VP7 were closely related to porcine rotaviruses (95–99% identity at amino acid level) and clustered with the porcine strains in phylogenetic analysis. In addition, it had subgroup I nature and belonged to NSP4 genotype B which is characteristic of animal rotaviruses. This is the first report of a rotavirus with VP6 and NSP4, two crucial proteins thought to be involved in host range restriction and pathogenicity, were of porcine origin and caused diarrhoea in a human host. Among the genes of this strain sequenced so far, only VP7 had highest identity to human strains at amino acid level. This study suggests reassortment may be occurring between human and other animal strains and some of the reassortant viruses may be virulent to humans.  相似文献   
86.
This study aims to determine the clinical features and seasonal patterns associated with shigellosis, the antimicrobial resistance frequencies of the isolates obtained during the period 2006–2012 for 22 antibiotics, and the molecular characterization of multidrug-resistant strains isolated from endemic cases of shigellosis in the remote islands of India, with special reference to fluoroquinolone and third-generation cephalosporins resistance. During the period from January 2006 to December 2011, stool samples were obtained and processed to isolate Shigella spp. The isolates were evaluated with respect to their antibiotic resistance pattern and various multidrug resistance determinants, including resistance genes, quinolone resistance determinants, and extended-spectrum β-lactamase (ESBL) production. Morbidity for shigellosis was found to be 9.3 % among children in these islands. Cases of shigellosis occurred mainly during the rainy seasons and were found to be higher in the age group 2–5 years. A wide spectrum of resistance was observed among the Shigella strains, and more than 50 % of the isolates were multidrug-resistant. The development of multidrug-resistant strains was found to be associated with various drug-resistant genes, multiple mutations in the quinolone resistance-determining region (QRDR), and the presence of plasmid-mediated quinolone-resistant determinants and efflux pump mediators. This report represents the first presentation of the results of long-term surveillance and molecular characterization concerning antimicrobial resistances in clinical Shigella strains in these islands. Information gathered as part of the investigations will be instrumental in identifying emerging antimicrobial resistance, for developing treatment guidelines appropriate for that community, and to provide baseline data with which to compare outbreak strains in the future.  相似文献   
87.
The immunology database and analysis portal (ImmPort) system is the archival repository and dissemination vehicle for clinical and molecular datasets created by research consortia funded by the National Institute of Allergy and Infectious Diseases Division of Allergy, Immunology, and Transplantation. With nearly 100 datasets now publicly available and hundreds of downloads per month, ImmPort is an important source for raw data and protocols from clinical trials, mechanistic studies, and novel methods for cellular and molecular measurements. To facilitate data transfer, templates for data representation and standard operating procedures have also been created and are also publicly available. ImmPort facilitates transparency and reproducibility in immunology research, serves as an important resource for education, and enables newly generated hypotheses and data-driven science.  相似文献   
88.
These guidelines, written for clinicians, contains evidence-based recommendations for the prevention of hospital acquired infections Hospital acquired infections are a major cause of mortality and morbidity and provide challenge to clinicians. Measures of infection control include identifying patients at risk of nosocomial infections, observing hand hygiene, following standard precautions to reduce transmission and strategies to reduce VAP, CR-BSI, CAUTI. Environmental factors and architectural lay out also need to be emphasized upon. Infection prevention in special subsets of patients - burns patients, include identifying sources of organism, identification of organisms, isolation if required, antibiotic prophylaxis to be used selectively, early removal of necrotic tissue, prevention of tetanus, early nutrition and surveillance. Immunodeficient and Transplant recipients are at a higher risk of opportunistic infections. The post tranplant timetable is divided into three time periods for determining risk of infections. Room ventilation, cleaning and decontamination, protective clothing with care regarding food requires special consideration. Monitoring and Surveillance are prioritized depending upon the needs. Designated infection control teams should supervise the process and help in collection and compilation of data. Antibiotic Stewardship Recommendations include constituting a team, close coordination between teams, audit, formulary restriction, de-escalation, optimizing dosing, active use of information technology among other measure. The recommendations in these guidelines are intended to support, and not replace, good clinical judgment. The recommendations are rated by a letter that indicates the strength of the recommendation and a Roman numeral that indicates the quality of evidence supporting the recommendation, so that readers can ascertain how best to apply the recommendations in their practice environments.  相似文献   
89.

Background

When this trial was initiated, the combined measles, mumps and rubella (MMR) vaccine was licensed for subcutaneous administration in all European countries and for intramuscular administration in some countries, whereas varicella vaccine was licensed only for subcutaneous administration. This study evaluated the intramuscular administration of an MMR vaccine (M-M-RvaxPro®) and a varicella vaccine (VARIVAX®) compared with the subcutaneous route.

Methods

An open-label randomised trial was performed in France and Germany. Healthy children, aged 12 to18 months, received single injections of M-M-RvaxPro and VARIVAX concomitantly at separate injection sites. Both vaccines were administered either intramuscularly (IM group, n = 374) or subcutaneously (SC group, n = 378). Immunogenicity was assessed before vaccination and 42 days after vaccination. Injection-site erythema, swelling and pain were recorded from days 0 to 4 after vaccination. Body temperature was monitored daily between 0 and 42 days after vaccination. Other adverse events were recorded up to 42 days after vaccination and serious adverse events until the second study visit.

Results

Antibody response rates at day 42 in the per-protocol set of children initially seronegative to measles, mumps, rubella or varicella were similar between the IM and SC groups for all four antigens. Response rates were 94 to 96% for measles, 98% for both mumps and rubella and 86 to 88% for varicella. For children initially seronegative to varicella, 99% achieved the seroconversion threshold (antibody concentrations of ≥ 1.25 gpELISA units/ml). Erythema and swelling were the most frequently reported injection-site reactions for both vaccines. Most injection-site reactions were of mild intensity or small size (≤ 2.5 cm). There was a trend for lower rates of injection-site erythema and swelling in the IM group. The incidence and nature of systemic adverse events were comparable for the two routes of administration, except varicella-like rashes, which were less frequent in the IM group.

Conclusion

The immunogenicities of M-M-RvaxPro and VARIVAX administered by the intramuscular route were comparable with those following subcutaneous administration, and the tolerability of the two vaccines was comparable regardless of administration route. Integration of both administration routes in the current European indications for the two vaccines will now allow physicians in Europe to choose their preferred administration route in routine clinical practice.

Trial registration

ClinicalTrials.gov NCT00432523  相似文献   
90.
The gracilis muscle is a Class II muscle that is often used in free tissue transfer. The muscle has multiple secondary pedicles, of which the first one is the most consistent in terms of position and calibre. Each pedicle can support a segment of the muscle thus yielding multiple small flaps from a single, long muscle. Although it has often been split longitudinally along the fascicles of its nerve for functional transfer, it has rarely been split transversely to yield multiple muscle flaps that can be used to cover multiple wounds in one patient without subjecting him/her to the morbidity of multiple donor areas.  相似文献   
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