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The fracture assessment tool (FRAX) is widely used for predicting fractures, but better methods are needed. The aim of this study was to determine whether visual assessments of mandibular trabecular bone could improve FRAX predictions. Three age‐cohorts of women were examined twice – 499 women in 1980/1981 and 412 women in 1992/1993; 397 participated in both examinations. Information on 10‐yr fracture events was available, and bone trabeculation was assessed in radiographs as ‘dense’, ‘mixed’, or ‘sparse’. Fracture assessment tool values, without bone mineral density (BMD), were calculated twice. Both sparse trabeculation and FRAX >15% were associated with a twofold higher risk for future fracture in the younger group and with a three‐ to fourfold higher risk for future fracture in the older group. For those with both FRAX >15% and sparse trabeculation, the relative risk (RR) for a fracture in the next 10 yr was 5.9 (95% CI: 3.5–9.8) in the younger group and 22.7 (95% CI: 5.6–92) in the older group. If either FRAX >15% or sparse trabeculation was present, the RR was 2.6 (95% CI: 1.7–4.1) in the younger group and 15.7 (95% CI: 3.9–6.4) in the older group. We concluded that FRAX >15%, without BMD measurements, was an effective fracture predictor, and mandibular sparse trabeculation had a substantial additive effect. Together, FRAX plus mandibular sparse trabeculation predicts major osteoporotic fractures to approximately the same extent as does FRAX with BMD measurements.  相似文献   
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The aim of this study was to determine the dissemination of Clostridium difficile (CD) spores in a hospital setting where the potassium monopersulfate‐based disinfectant VirkonTM was used for cleaning. In the initial part of the study, we sampled 16 areas of frequent patient contact in 10 patient rooms where a patient with CD infection (CDI) had been accommodated. In the second part of the study, we obtained samples from 10 patient beds after discharge of CDI patients, both before and after the beds were cleaned. In the first part, CDspores were isolated in only 30% of the rooms. In the second part, which focused on transmission to hospital beds, C. difficile was found in four of 10 beds either before or after cleaning. In conclusion, in both parts of the study, we demonstrated a moderate spread of CD spores to the environment despite routine cleaning procedures involving VirkonTM.  相似文献   
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The lack of an effective licensed vaccine remains one of the most significant gaps in the portfolio of tools being developed to eliminate Plasmodium falciparum malaria. Vaccines targeting erythrocyte invasion – an essential step for both parasite development and malaria pathogenesis – have faced the particular challenge of genetic diversity. Immunity-driven balancing selection pressure on parasite invasion proteins often results in the presence of multiple, antigenically distinct, variants within a population, leading to variant-specific immune responses. Such variation makes it difficult to design a vaccine that covers the full range of diversity, and could potentially facilitate the evolution of vaccine-resistant parasite strains. In this study, we investigate the effect of genetic diversity on invasion inhibition by antibodies to a high priority P. falciparum invasion candidate antigen, P. falciparum Reticulocyte Binding Protein Homologue 5 (PfRH5). Previous work has shown that virally delivered PfRH5 can induce antibodies that protect against a wide range of genetic variants. Here, we show that a full-length recombinant PfRH5 protein expressed in mammalian cells is biochemically active, as judged by saturable binding to its receptor, basigin, and is able to induce antibodies that strongly inhibit P. falciparum growth and invasion. Whole genome sequencing of 290 clinical P. falciparum isolates from across the world identifies only five non-synonymous PfRH5 SNPs that are present at frequencies of 10% or more in at least one geographical region. Antibodies raised against the 3D7 variant of PfRH5 were able to inhibit nine different P. falciparum strains, which between them included all of the five most common PfRH5 SNPs in this dataset, with no evidence for strain-specific immunity. We conclude that protein-based PfRH5 vaccines are an urgent priority for human efficacy trials.  相似文献   
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OBJECTIVE: To investigate the relationship between motor performance and white matter lesions (WMLs) on computed tomography (CT) of the brain in older women. DESIGN: Cross-sectional study. SETTING: Population-based study in G?teborg, Sweden. PARTICIPANTS: A total of 248 women aged 70, 74, and 78 years. MEASUREMENTS: Motor performance was measured by a Postural-Locomotion-Manual (PLM) test using an optoelectronic technique. WMLs on CT scans were rated as no, mild, moderate, or severe. RESULTS: White matter lesions were associated with impaired mobility of the lower extremities, that is, prolonged locomotion phase in the PLM test. This association was also present after controlling for age, hypertension, coronary heart disease, stroke, diabetes mellitus, chronic bronchitis, intermittent claudication, and smoking. CONCLUSIONS: Cerebral white matter lesions may contribute to motor impairments in older adults.  相似文献   
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Background

Rapid societal changes occurred in the Western world during the 20th century. It is not clear whether this has changed the relation between social factors and depression in older people.

Methods

Representative samples of 70-year-olds from Gothenburg, Sweden, were examined with identical psychiatric examinations in 1971–72 (N=392; 226 women and 166 men) and 2000–01 (N=499; 270 women and 229 men). Follow-up studies were conducted after five years. Social factors were obtained by self-report and depression was diagnosed according to DSM-IV-TR.

Results

Feelings of loneliness were related to both concurrent depression at baseline and new depression at follow-up in both birth cohorts. Visits with others than children and neighbours once per month or less, compared to having more visits, and the perception of having too little contact with others, were related to both concurrent and new depression in 70-year-olds examined 1971–72, but not in those examined 30 years later.

Limitations

The response rate declined from 85.2% in 1971–72 to 65.8% in 2000–01. Participation bias may have resulted in an underestimation of depression in the later-born cohort.

Conclusions

Social contacts with others were related to depression in 70-year-olds examined in the 1970s, but not in those examined in the 2000s. This may reflect period changes in the ways of socialising, communicating and entertaining, e.g. due to technological development and expansion of mass media. Findings may be useful when developing modern and effective programs for the prevention of mental ill-health in older people.  相似文献   
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