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321.
BACKGROUND: The importance of blood safety in public health was recognized long ago, and data are essential to plan strategies to improve the status. This study aims to obtain data on blood donor and blood donation characteristics that would complement blood safety data from national and international organizations.
MATERIALS AND METHODS: A questionnaire was sent to seven Francophone countries (Burkina Faso, Cameroon, Congo, Ivory Coast, Mali, Niger, and Rwanda) and was structured to obtain objective data on blood donors and donated blood and in administrative and technical organization.
RESULTS: The results reflect a poor level of organization of blood transfusion centers in large regions of the African continent, insufficient supply of blood products, high prevalence of transfusion-transmitted infections, limited financial resources, a lack of well-trained personnel, and cultural obstacles. Six countries had less than 50% of their personnel trained in transfusion medicine. Only one country had the entire standard operating procedure written. Female donors represented less than 30% of the donors and the range of percentage of hepatitis B found in donors was 2.76% to 18.96%.
CONCLUSION: The inclusion of these regions in future blood safety surveys and in the development of national blood transfusion programs is essential and will undoubtedly require the assistance of international organizations.  相似文献   
322.
In rural, malaria-endemic Burkina Faso, we evaluated the impact of the use of pre-packaged antimalarial drugs (PPAM), by mothers in the home, on the progression of disease in children from uncomplicated fever to severe malaria. In each village of one province, a core group of opinion leaders (mainly older mothers) was trained in the management of uncomplicated malaria, including the administration of PPAM. Full courses of antimalarial (chloroquine) and antipyretic (aspirin) drugs were packaged in age-specific bags and made widely available through community health workers who were supplied through the existing drug distribution system. Drugs were sold under a cost-recovery scheme. Local schoolteachers conducted surveys in a random sample of 32 villages at the end of the high transmission seasons in 1998 and 1999. Disease history and the treatment received were investigated for all children under the age of 6 years having suffered from a fever episode in the previous 4 weeks. 'Uncomplicated malaria' was defined as every episode of fever and 'severe malaria' as every episode of fever followed by convulsions or loss of consciousness. During the study period, 56%[95% confidence interval (CI) 50-62%] of 3202 fever episodes in children under 6 years of age were treated promptly by mothers with the pre-packaged drugs made available by the study. A total of 59% of children receiving PPAM were reported to have received the drugs over the prescribed 3-day period, while 52% received the correct age-specific dose. PPAM use was similar among literate (61%) and non-literate mothers (55%) (P = 0.08). The overall reported risk of developing severe malaria was 8%. This risk was lower in children treated with PPAM (5%) than in children not treated with PPAM (11%) (risk ratio = 0.47; 95% CI 0.37, 0.60; P < 0.0001). This estimate of the impact of PPAM was largely unchanged when account was taken of potential confounding by age, sex, maternal literacy status, year or village. Our findings support the view that, after appropriate training and with adequately packaged drugs made available, mothers can recognize and treat promptly and correctly malarial episodes in their children and, by doing so, reduce the incidence of severe disease.  相似文献   
323.
Folic acid is frequently given to pregnant women at the same time as intermittent preventive treatment (IPTp) with sulfadoxine/pyrimethamine (SP), but it is not known if it interferes with the anti-malarial activity of SP. To investigate this concern, 1,035 Gambian primigravidae were randomized to receive either folic acid (500-1,500 microg/day) together with oral iron (522) or oral iron alone (513) for 14 days at the same time as they received IPTp with SP. On presentation, 261 women (25%) had Plasmodium falciparum asexual parasitemia. Prevalences of parasitemia on day 14 after treatment were similar in both groups: 5.7% (26 of 458) in the iron plus folic acid group and 4.9% (22 of 446) in the iron alone group (risk difference = 0.74%, 95% confidence interval [CI] = -2.2% to 3.7%). Parasitologic cure was observed in 116 (91%) of 128 of women who were parasitemic on presentation and who received iron and folic acid and in 122 (92%) of 133 women who received iron alone (difference = 1.1%, 95% CI = -5.6% to 8.0%). Women who received folic acid and iron had a slightly higher mean hemoglobin concentration at day 14 than women who had received iron alone (difference = 0.14 g/dL, 95% CI = 0.01-0.27 g/dL). The results of this study suggest that in an area of low SP resistance, administration of folic acid to pregnant women in a dose of 500-1,500 mug/day will not interfere with the protective effect of SP when used for IPTp.  相似文献   
324.
325.
NADPH oxidase 5 (NOX5) generated reactive oxygen species (ROS) have been implicated in signaling cascades that regulate cancer cell proliferation. To evaluate and validate NOX5 expression in human tumors, we screened a broad range of tissue microarrays (TMAs), and report substantial overexpression of NOX5 in malignant melanoma and cancers of the prostate, breast, and ovary. In human UACC‐257 melanoma cells that possesses high levels of functional endogenous NOX5, overexpression of NOX5 resulted in enhanced cell growth, increased numbers of BrdU positive cells, and increased γ‐H2AX levels. Additionally, NOX5‐overexpressing (stable and inducible) UACC‐257 cells demonstrated increased normoxic HIF‐1α expression and decreased p27Kip1 expression. Similarly, increased normoxic HIF‐1α expression and decreased p27Kip1 expression were observed in stable NOX5‐overexpressing clones of KARPAS 299 human lymphoma cells and in the human prostate cancer cell line, PC‐3. Conversely, knockdown of endogenous NOX5 in UACC‐257 cells resulted in decreased cell growth, decreased HIF‐1α expression, and increased p27Kip1 expression. Likewise, in an additional human melanoma cell line, WM852, and in PC‐3 cells, transient knockdown of endogenous NOX5 resulted in increased p27Kip1 and decreased HIF‐1α expression. Knockdown of endogenous NOX5 in UACC‐257 cells resulted in decreased Akt and GSK3β phosphorylation, signaling pathways known to modulate p27Kip1 levels. In summary, our findings suggest that NOX5 expression in human UACC‐257 melanoma cells could contribute to cell proliferation due, in part, to the generation of high local concentrations of extracellular ROS that modulate multiple pathways that regulate HIF‐1α and networks that signal through Akt/GSK3β/p27Kip1.  相似文献   
326.
Plasmodium falciparum resistance to chloroquine first arose in Africa 25 years ago. Nowadays most of African malaria control programmes have switched their first-line treatment of uncomplicated malaria cases towards artemisinin derivatives combination. After WHO guidelines, a survey network for malaria treatment resistance has been set up in the Niger valley around Niamey since December 2004. The association of the Niger national malaria control programme with the CERMES research center allowed collecting of samples from both health centers and hospitals of this region. Blood finger-pricks on filter papers were tested for detection of plasmodial antigen in health center without biological diagnosis capacity. Specimens found positive either in hospital laboratory or by using antigen method were tested by PCR/RFLP to detect K76T mutations on the pfcrt gene and S108N mutation on the pfdhfr gene. This simple procedure allows the screening of a large number of specimens. Moreover, a spatial distribution of mutations and evidence of resistance clusters were searched integrating the data in a geographic information system. The 76T mutation of pfcrt and 108N of pfdhfr were respectively found in 50.8% and 57% of the specimens tested. No statistically significant difference was found according to the level of sanitary formations or the age of the patients. No resistance cluster was identified and the prevalence of mutation seems homogeneous in the zone. By completing the clinical efficacy studies we think that our simple method for collecting and testing blood samples associated with clinical efficacy studies may be useful for building a network of malaria drug resistance in Africa.  相似文献   
327.
328.
World Journal of Surgery - To evaluate FCH-PET/CT and parathyroid 4D-CT so as to guide surgery in patients with primary hyperparathyroidism (pHPT) and prior neck surgery. Medical records of all...  相似文献   
329.
Cervical cancer is the main cancer among women in sub-Saharan Africa, India and other parts of the developing world. Evaluation of screening performance of effective, feasible and affordable early detection and management methods is a public health priority. Five screening methods, naked eye visual inspection of the cervix uteri after application of diluted acetic acid (VIA), or Lugol's iodine (VILI) or with a magnifying device (VIAM), the Pap smear and human papillomavirus testing with the high-risk probe of the Hybrid Capture-2 assay (HC2), were evaluated in 11 studies in India and Africa. More than 58,000 women, aged 25-64 years, were tested with 2-5 screening tests and outcome verification was done on all women independent of the screen test results. The outcome was presence or absence of cervical intraepithelial neoplasia (CIN) of different degrees or invasive cervical cancer. Verification was based on colposcopy and histological interpretation of colposcopy-directed biopsies. Negative colposcopy was accepted as a truly negative outcome. VIA showed a sensitivity of 79% (95% CI 73-85%) and 83% (95% CI 77-89%), and a specificity of 85% (95% CI 81-89%) and 84% (95% CI 80-88%) for the outcomes CIN2+ or CIN3+, respectively. VILI was on average 10% more sensitive and equally specific. VIAM showed similar results as VIA. The Pap smear showed lowest sensitivity, even at the lowest cutoff of atypical squamous cells of undetermined significance (57%; 95% CI 38-76%) for CIN2+ but the specificity was rather high (93%; 95% CI 89-97%). The HC2-assay showed a sensitivity for CIN2+ of 62% (95% CI 56-68%) and a specificity of 94% (95% CI 92-95%). Substantial interstudy variation was observed in the accuracy of the visual screening methods. Accuracy of visual methods and cytology increased over time, whereas performance of HC2 was constant. Results of visual tests and colposcopy were highly correlated. This study was the largest ever done that evaluates the cross-sectional accuracy of screening tests for cervical cancer precursors in developing countries. The merit of the study was that all screened subjects were submitted to confirmatory investigations avoiding to verification bias. A major finding was the consistently higher sensitivity but equal specificity of VILI compared with VIA. Nevertheless, some caution is warranted in the interpretation of observed accuracy measures, since a certain degree of gold standard misclassification cannot be excluded. Because of the correlation between visual screening tests and colposcopy and a certain degree of over-diagnosis of apparent CIN2+ by study pathologists, it is possible that both sensitivity and specificity of VIA and VILI were overestimated. Gold standard verification error could also explain the surprisingly low sensitivity of HC2, which contrasts with findings from other studies.  相似文献   
330.
Background: Brief sevoflurane exposure and washout (sevoflurane preconditioning [SPC]) before 30-min global ischemia at 37[degrees]C is known to improve cardiac function, decrease cytosolic [Ca2+] loading, and reduce infarct size on reperfusion. It is not known if anesthetic preconditioning (APC) applies as well to hypothermic ischemia and reperfusion and if KATP channels are involved. The authors examined in guinea pig isolated hearts the effect of sevoflurane exposure before 4-h global ischemia at 17[degrees]C on cardiac function, cytosolic [Ca2+] loading, and infarct size. In addition they tested the potential role of the mitochondrial KATP channel in eliciting the cardioprotection by SPC.

Methods: Hearts were randomly assigned to (1) a nontreated hypothermic ischemia group (CON), (2) a group given 3.5 vol% sevoflurane for 15 min with a 15-min washout before hypothermic ischemia (SPC), and (3) an SPC group in which anesthetic exposure was bracketed with 200 [mu]m 5-hydroxydecanoate (5-HD) from 5 min before until 5 min after sevoflurane (SPC + 5-HD). Cytosolic [Ca2+] was measured in the left ventricular (LV) free wall with the intracellularly loaded fluorescence probe indo-1.

Results: Initial reperfusion in CON hearts markedly increased systolic and diastolic [Ca2+] and reduced contractility (dLVP/dtmax), relaxation (diastolic LVP, dLVP/dtmin), myocardial oxygen consumption (Mvo2), and cardiac efficiency. In SPC hearts, cytosolic [Ca2+] overloading (especially diastolic [Ca2+]) was decreased with increased myocardial [Ca2+] influx (d[Ca2+]/dtmax) and efflux (d[Ca2+]/dtmin), improved contractility, relaxation, coronary flow, Mvo2, cardiac efficiency, and decreased infarct size. In SPC + 5HD hearts, the reduction in infarct size was antagonized by 5-HD, but functional return was less affected by 5-HD.  相似文献   

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