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991.
992.
993.

Background

Improved treatment options for people with haemophilia (PWH) have increased the possibilities for sports participation, but the risk of sports-induced bleeding (SIB) is still considered considerable by many.

Aim

To assess sports associated injury- and bleeding risk in PWH and to assess clotting levels associated with safe sports participation.

Methods

Sports injuries and SIBs were prospectively collected for 12 months in PWH aged 6–49 without inhibitors playing sports at least once weekly. Injuries were compared according to factor levels, severity, joint health, sports risk category and sports intensity. Factor activity at the time of injury was estimated using a pharmacokinetic model.

Results

125 participants aged 6–49 (41 children, 90% haemophilia A; 48% severe, 95% severe on prophylaxis) were included. Sports injuries were reported by 51 participants (41%). Most participants (62%) reported no bleeds at all and only 16% reported SIBs. SIBs were associated with factor levels at time of injury (OR: 0.93/%factor level (CI 0.88–0.99); p = .02), but not with haemophilia severity (OR: 0.62 (CI 0.20–1.89); p = .40), joint health, sports risk category or sports intensity. PWH with factor levels <10% during sports injury had a bleeding risk of 41% versus 20% in those with higher (>10%) factor levels.

Conclusion

The results of this study emphasize the importance of clotting factor levels in prevention of bleeds. This information is vital for patient counselling and tailoring prophylactic treatment with clotting factors and non-replacement therapy.  相似文献   
994.
BACKGROUND: Health-seeking and sexual behaviors are important elements in the control of sexually transmitted infections (STIs). GOAL: To examine patterns of health-seeking behavior and related sexual behavior relevant to improved prevention and care among patients attending primary healthcare (PHC) clinics. STUDY DESIGN: A questionnaire covering social, demographic, and healthcare-seeking and sexual behavior information was administered to 555 patients attending three primary healthcare clinics in low socioeconomic areas of Nairobi, Kenya. RESULTS: Women's knowledge about health in general and STIs in particular was poor. A major gender difference in delay of health seeking for STIs was observed (5 days for men versus 14 days for women). Significantly more men than women reported a history of STIs (68% versus 47%; P = 0.04). Men reported more extramarital affairs (17% versus 8%; P < 0.001). A high prevalence of gonorrhea (3%) and chlamydia (6%) was found in this population, with no difference between the genders. The urine dipstick was ineffective for the detection of these STIs. CONCLUSIONS: There is a need for better understanding of behavioral factors, as well as gender and social aspects of health care. Health education and health promotion in these areas should be strengthened. Improved screening tests are needed for the detection of STI.  相似文献   
995.
On March 15, 2010, a highly pathogenic avian influenza virus was isolated from the carcass of a common buzzard (Buteo buteo) in Bulgaria. Phylogenetic analyses of the virus showed a close genetic relationship with influenza virus A (H5N1) clade 2.3.2.1 viruses isolated from wild birds in the Tyva Republic and Mongolia during 2009–2010. Designated A/common buzzard/Bulgaria/38WB/2010, this strain was highly pathogenic in chickens but had low pathogenicity in mice and ferrets and no molecular markers of increased pathogenicity in mammals. The establishment of clade 2.3.2.1 highly pathogenic avian influenza viruses of the H5N1 subtype in wild birds in Europe would increase the likelihood of health threats to humans and poultry in the region.  相似文献   
996.
997.
Cerebral microbleeds (CMBs) are frequent findings in MRI scans of elderly subjects. Depending on the MRI protocols applied 4.7% to 24.4% of community-based subjects show incidental CMBs. The rates reported for various types of ischemic strokes and intracerebral hemorrhages vary between 19.4% and 68.5%. Most studies also demonstrated CMBs in approximately one third of Alzheimer cases. A lobar distribution of CMBs is considered to relate to cerebral amyloid angiopathy, while CMBs located in the basal ganglia or in infratentorial brain regions are thought to relate to hypertensive vasculopathy. Besides age, hypertension, diabetes mellitus, and low serum cholesterol have so far been identified as risk factors for CMBs. Presence of an APOE ε4 allele is the only genetic factor that was consistently shown to increase the risk for CMB development. There are only few longitudinal studies on the predictive value of CMBs. For incident ischemic strokes and intracerebral hemorrhages hazard ratios of 4.48 and 50.2 have been reported. CMBs also doubled the risk for conversion to dementia in MCI patients, and there are indications for CMBs being possible predictors of increased mortality. Given the small number of longitudinal investigations with often small sample sizes the role of CMBs as predictors of disease needs to be further elucidated. CMBs were significantly more common in warfarin-treated stroke patients who developed intracerebral hemorrhages (ICH). These data are cross-sectional. They do not provide enough evidence to consider CMBs as a contraindication for antithrombotic agents in primary and secondary stroke prevention. CMBs are likely to unfavourably affect cognitive functioning. It remains to be determined if direct lesion-related effects are responsible for this finding or if CMBs are sole markers of more extensive tissue damage in the wake of cerebral small vessel disease leading to widespread visible but also non-visible tissue destruction with a high likelihood for cognitive consequences.  相似文献   
998.
Background: Polonium-210 (210Po) concentrations that exceed 1 Bq/L in drinking-water supplies have been reported from four widely separated U.S. states where exposure to it went unnoticed for decades. The radionuclide grandparents of 210Po are common in sediments, and segments of the public may be chronically exposed to low levels of 210Po in drinking water or in food products from animals raised in contaminated areas.Objectives: We summarized information on the environmental behavior, biokinetics, and toxicology of 210Po and identified the need for future research.Methods: Potential linkages between environmental exposure to 210Po and human health effects were identified in a literature review.Discussion: 210Po accumulates in the ovaries where it kills primary oocytes at low doses. Because of its radiosensitivity and tendency to concentrate 210Po, the ovary may be the critical organ in determining the lowest injurious dose for 210Po. 210Po also accumulates in the yolk sac of the embryo and in the fetal and placental tissues. Low-level exposure to 210Po may have subtle, long-term biological effects because of its tropism towards reproductive and embryonic and fetal tissues where exposure to a single alpha particle may kill or damage critical cells. 210Po is present in cigarettes and maternal smoking has several effects that appear consistent with the toxicology of 210Po.Conclusions: Much of the important biological and toxicological research on 210Po is more than four decades old. New research is needed to evaluate environmental exposure to 210Po and the biological effects of low-dose exposure to it so that public health officials can develop appropriate mitigation measures where necessary.  相似文献   
999.

Background

Promoting the neuroprotective and repair-inducing effector functions of microglia and macrophages, by means of M2 polarisation or alternative activation, is expected to become a new therapeutic approach for central nervous system (CNS) disorders in which detrimental pro-inflammatory microglia and/or macrophages display a major contribution to the neuropathology. In this study, we present a novel in vivo approach using intracerebral grafting of mesenchymal stem cells (MSC) genetically engineered to secrete interleukin 13 (IL13-MSC).

Methods

In the first experimental setup, control MSC and IL13-MSC were grafted in the CNS of eGFP+ bone marrow chimaeric C57BL/6 mice to histologically evaluate IL13-mediated expression of several markers associated with alternative activation, including arginase1 and Ym1, on MSC graft-recognising microglia and MSC graft-infiltrating macrophages. In the second experimental setup, IL13-MSC were grafted on the right side (or on both the right and left sides) of the splenium of the corpus callosum in wild-type C57BL/6 mice and in C57BL/6 CX3CR1eGFP/+CCR2RFP/+ transgenic mice. Next, CNS inflammation and demyelination was induced by means of a cuprizone-supplemented diet. The influence of IL13-MSC grafting on neuropathological alterations was monitored by non-invasive T 2-weighted magnetic resonance imaging (MRI) and quantitative histological analyses, as compared to cuprizone-treated mice with control MSC grafts and/or cuprizone-treated mice without MSC injection.

Results

In the first part of this study, we demonstrate that MSC graft-associated microglia and MSC graft-infiltrating macrophages are forced into alternative activation upon grafting of IL13-MSC, but not upon grafting of control MSC. In the second part of this study, we demonstrate that grafting of IL13-MSC, in addition to the recruitment of M2 polarised macrophages, limits cuprizone-induced microgliosis, oligodendrocyte death and demyelination. Furthermore, we here demonstrate that injection of IL13-MSC at both sides of the splenium leads to a superior protective effect as compared to a single injection at one side of the splenium.

Conclusions

Controlled and localised production of IL13 by means of intracerebral MSC grafting has the potential to modulate cell graft- and pathology-associated microglial/macrophage responses, and to interfere with oligodendrocyte death and demyelinating events in the cuprizone mouse model.
  相似文献   
1000.

Background

Advanced genomic techniques such as Next-Generation-Sequencing (NGS) and gene expression profiling, including NanoString, are vital for the development of personalised medicines, as they enable molecular disease classification. This has become increasingly important in the treatment of cancer, aiding patient selection. However, it requires efficient nucleic acid extraction often from formalin-fixed paraffin-embedded tissue (FFPE).

Methods

Here we provide a comparison of several commercially available manual and automated methods for DNA and/or RNA extraction from FFPE cancer cell line samples from Qiagen, life Technologies and Promega. Differing extraction geometric mean yields were evaluated across each of the kits tested, assessing dual DNA/RNA extraction vs. specialised single extraction, manual silica column based extraction techniques vs. automated magnetic bead based methods along with a comparison of subsequent nucleic acid purity methods, providing a full evaluation of nucleic acids isolated.

Results

Out of the four RNA extraction kits evaluated the RNeasy FFPE kit, from Qiagen, gave superior geometric mean yields, whilst the Maxwell 16 automated method, from Promega, yielded the highest quality RNA by quantitative real time RT-PCR. Of the DNA extraction kits evaluated the PicoPure DNA kit, from Life Technologies, isolated 2–14× more DNA. A miniaturised qPCR assay was developed for DNA quantification and quality assessment.

Conclusions

Careful consideration of an extraction kit is necessary dependent on quality or quantity of material required. Here we provide a flow diagram on the factors to consider when choosing an extraction kit as well as how to accurately quantify and QC the extracted material.
  相似文献   
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