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91.
The Workshop on Osteoporosis, Falls and Fractures (GCOF) of The Spanish Geriatrics and Gerontology Society (SEGG) formed a committee in order to review the state of the art on the detection, risk factors and assessment tools for falls, and intervention protocols when falls occurs in nursing homes, long-term hospitals or medium-stay units. The different patient profiles are described in order to make a comprehensive approach to this heterogeneous topic and population, offering a risk classification and specific advice according to these categories.  相似文献   
92.
ABSTRACT Sierra Madre Sparrows (Xenospiza baileyi) are among the least known of all bird species in Mexico. Recent surveys have discovered previously unknown populations and the current known distribution of Sierra Madre Sparrows consists of two populations separated by >800 km. We used available distributional information to develop ecological niche models that (1) predict much of the distribution potential of the species, (2) establish that the broad disjunction separating the two populations has ecological correlates that appear to be important to the distributional of these sparrows, and (3) illustrate the extremely restricted ecological distribution of the species. We used two sets of climatic and topographic variables, with one including all 22 variables available and the second with only six variables that were positively related to quality of distributional models. Although indications of differences between the two sets of populations were found based on the full 22‐dimensional environmental dataset, such a highly dimensional analysis is vulnerable to over‐fitting; models based on the reduced dataset indicated that the two populations occur in areas with similar ecological conditions. Our models also suggest that southern population of Sierra Madre Sparrows covers most of their potential range in that region. The potential range of the northern population, however, extends beyond known points of occurrence. To clarify the distribution of Sierra Madre Sparrows and evaluate their status and conservation opportunities, detailed searches for additional populations in areas identified by the model are needed.  相似文献   
93.
Scavenger receptor gp340 aggregates group A streptococci by binding pili   总被引:1,自引:0,他引:1  
Group A streptococci (GAS) are the most frequent cause of bacterial pharyngitis. The first obstacle to GAS colonization of the pharynx is saliva. As well as forming a physical barrier, saliva contains components of innate and acquired immunity. Previous work has shown that saliva induces bacterial aggregation, which may serve as a clearance mechanism. As the aggregation of some oral streptococci in saliva is mediated by long proteinaceous appendages, we hypothesized that pili of GAS might behave similarly. Wild-type GAS M1 strain SF370 aggregated in saliva, while pilus-defective mutants did not. Similarly, heterologous expression of diverse GAS pili on the surface of Lactococcus lactis induced aggregation in saliva, while control strains were unaffected. Further studies revealed that aggregating bacteria bound salivary component gp340. Purified gp340 aggregated wild-type GAS and L. lactis expressing GAS pili, but not control strains. GAS pilus-defective mutants were abrogated in gp340 binding and aggregation. Furthermore, gp340-mediated aggregation reduced bacterial adhesion to human epithelial cells, suggesting a role in host defence.  相似文献   
94.
This paper explores client satisfaction with abortion care, looking at overall satisfaction and satisfaction with hygiene, comfort and courtesy. The analysis aimed to determine whether client satisfaction was related to the characteristics of the client, in order to guide quality improvement efforts. The analysis is a secondary analysis of data collected in a survey of 489 abortion clients who attended a limited number of hospitals in three cities in Russia. The data were analysed using logistic regression. Client characteristics, in general, did not affect overall satisfaction though there were significant differences in overall satisfaction for unmarried versus married women (OR=0.29, CI=0.13, 0.63). Similarly, most characteristics of the abortion visit were not related to client satisfaction, although women who were awake for the procedure were less likely to be satisfied (OR=0.37, CI=0.16, 0.89). Information provided to abortion clients about self-care was the most important predictor of overall satisfaction for abortion clients (OR=3.55, CI=1.64, 7.69). This suggests that improving the information provided to clients, through training providers and other staff, is important in these settings.  相似文献   
95.

Background

Recently, the 13-valent pneumococcal conjugate vaccine (PCV13) has been recommended for adults. We analyzed the epidemiology of invasive pneumococcal disease (IPD) in older adults in Spain before PCV13 introduction.

Methodology/Principal Findings

IPD episodes, defined as clinical findings together with an invasive pneumococcal isolate, were prospectively collected from patients aged over 65 years in three hospitals in Spain from 2007 to 2009. A total of 335 IPD episodes were collected. Pneumonia was the main clinical syndrome, while chronic obstructive pulmonary disease, diabetes mellitus and cancer were the main underlying diseases. Pneumococcal isolates were serotyped and the molecular typing was performed by PFGE/MLST. PCV13 serotypes accounted for 59.3% of isolates, the most prevalent being serotypes 19A (15.1%), 3 (9.6%), 7F (7.5%), 14 (6.9%) and 1 (5.4%). The most frequent non-PCV13 serotypes were serotypes 16F (4.5%), 22F (3.6%), 24F (3.3%) and 6C (2.1%). The most common genotypes were CC230 (8.5%, serotypes 19A and 24F), CC156 (8.2%, serotypes 9V and 14), ST191 (7.9%, serotype 7F), CC260 (6.6%, serotype 3), ST306 (5.2%, serotype 1), CC30 (4.6%, serotype 16F) and ST433 (3.6%, serotype 22F). Comparing the 335 IPD isolates to 174 invasive pneumococci collected at the same hospitals in 1999–2000, PCV7 serotypes decreased (45.4% vs 18.4%,p<0.001), non-PCV7 serotypes included in PCV13 increased (26.4% vs 41.0%,p = 0.001) and two non-PCV13 serotypes increased (serotype 6C 0% vs 2.1%, p = 0.05; serotype 24F 0.6% vs 3.3%, p = 0.04,).

Conclusion

In our older adult population two serotypes (19A and 3) included in PCV13 accounted for about a quarter of IPD episodes in people ≥65 years. Non-PCV13 emerging serotypes should be carefully monitored in future surveillance studies.  相似文献   
96.
Group A Streptococcus (GAS, Streptococcus pyogenes) is a Gram-positive human pathogen responsible for several acute diseases and autoimmune sequelae that account for half a million deaths worldwide every year. GAS infections require the capacity of the pathogen to adhere to host tissues and assemble in cell aggregates. Furthermore, a role for biofilms in GAS pathogenesis has recently been proposed. Here we investigated the role of GAS pili in biofilm formation. We demonstrated that GAS pilus-negative mutants, in which the genes encoding either the pilus backbone structural protein or the sortase C1 have been deleted, showed an impaired capacity to attach to a pharyngeal cell line. The same mutants were much less efficient in forming cellular aggregates in liquid culture and microcolonies on human cells. Furthermore, mutant strains were incapable of producing the typical three-dimensional layer with bacterial microcolonies embedded in a carbohydrate polymeric matrix. Complemented mutants had an adhesion and aggregation phenotype similar to the wild-type strain. Finally, in vivo expression of pili was indirectly confirmed by demonstrating that most of the sera from human patients affected by GAS-mediated pharyngitis recognized recombinant pili proteins. These data support the role of pili in GAS adherence and colonization and suggest a general role of pili in all pathogenic streptococci.  相似文献   
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Streptococcus agalactiae, also known as group B Streptococcus (GBS), is a primary colonizer of the anogenital mucosa of up to 40% of healthy women and an important cause of invasive neonatal infections worldwide. Among the 10 known capsular serotypes, GBS type III accounts for 30 to 76% of the cases of neonatal meningitis. In recent years, the ability of GBS to form biofilm attracted attention for its possible role in fitness and virulence. Here, a new in vitro biofilm formation protocol was developed to guarantee more stringent conditions, to better discriminate between strong-, low-, and non-biofilm-forming strains, and to facilitate interpretation of data. This protocol was used to screen the biofilm-forming abilities of 366 GBS clinical isolates from pregnant women and from neonatal infections of different serotypes in relation to medium composition and pH. The results identified a subset of isolates of serotypes III and V that formed strong biofilms under acidic conditions. Importantly, the best biofilm formers belonged to serotype III hypervirulent clone ST-17. Moreover, the abilities of proteinase K to strongly inhibit biofilm formation and to disaggregate mature biofilms suggested that proteins play an essential role in promoting GBS biofilm initiation and contribute to biofilm structural stability.  相似文献   
100.
Taurine is a conditionally essential amino acid for human that is involved in the control of glucose homeostasis; however, the mechanisms by which the amino acid affects blood glucose levels are unknown. Using an animal model, we have studied these mechanisms. Mice were supplemented with taurine for 30 d. Blood glucose homeostasis was assessed by intraperitoneal glucose tolerance tests (IPGTT). Islet cell function was determined by insulin secretion, cytosolic Ca2+ measurements and glucose metabolism from isolated islets. Islet cell gene expression and translocation was examined via immunohistochemistry and quantitative real-time polymerase chain reaction. Insulin signaling was studied by Western blot. Islets from taurine-supplemented mice had: (i) significantly higher insulin content, (ii) increased insulin secretion at stimulatory glucose concentrations, (iii) significantly displaced the dose-response curve for glucose-induced insulin release to the left, (iv) increased glucose metabolism at 5.6 and 11.1-mmol/L concentrations; (v) slowed cytosolic Ca2+ concentration ([Ca2+]i) oscillations in response to stimulatory glucose concentrations; (vi) increased insulin, sulfonylurea receptor-1, glucokinase, Glut-2, proconvertase and pancreas duodenum homeobox-1 (PDX-1) gene expression and (vii) increased PDX-1 expression in the nucleus. Moreover, taurine supplementation significantly increased both basal and insulin stimulated tyrosine phosphorylation of the insulin receptor in skeletal muscle and liver tissues. Finally, taurine supplemented mice showed an improved IPGTT. These results indicate that taurine controls glucose homeostasis by regulating the expression of genes required for glucose-stimulated insulin secretion. In addition, taurine enhances peripheral insulin sensitivity.  相似文献   
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