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Neurological disorders related to vitamin B12 deficiency are common in prisons of tropical Africa. We collected 22 cases (20 men and 2 women). They all showed vitamin B12 deficiency associated with neurological signs that were represented by sclerosis combined with bone marrow (n = 9), peripheral neuropathy (n = 6), cerebellar syndrome (n = 2), a pyramidal syndrome of the lower limbs (n = 4) and optic neuropathy (n = 1). Laboratory tests showed a mean hemoglobin concentration of 7.2 ± 1.5 g/dl, mean 104 ± 28 fl, macrocytic anemia in 10 patients. Biermer’s disease was identified in 9 patients, 3 patients showed the syndrome of non dissociation of vitamin B12, a gastrectomy in 2 patients and no etiology was identified in 8 patients.  相似文献   
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Cold cardioplegia protects against reperfusion damage. Blocking Na+/H+ exchange may be as protective as cardioplegia by improving the left ventricular pressure (LVP)-[Ca2+] relationship after cold ischemia. In guinea pig isolated hearts subjected to cold ischemia (4 h, 17 degrees C) and reperfusion, the cardioprotective effects of a Krebs-Ringer (KR) solution, a cardioplegia solution, a KR solution containing the Na+/H+ exchange inhibitor eniporide (1 microM), and a cardioplegia solution containing eniporide were compared. Treatments were given before and initially after cold ischemia. Systolic and diastolic [Ca2+] were calculated from indo-1 fluorescence transients recorded at the LV free wall. During ischemia, diastolic [Ca2+] increased in each group but more so in the KR group. Peak systolic and diastolic [Ca2+] on initial reperfusion were highest after KR and smallest after cardioplegia + eniporide. After reperfusion, systolic-diastolic LVP (% of baseline) and infarct size (%), respectively, were KR, 47 +/- 3%, 37 +/- 4%; cardioplegia, 71 +/- 5%*, 20 +/- 2.2%*; KR + eniporide, 73 +/- 5%*, 11 +/- 3%* dagger; and cardioplegia + eniporide 77 +/- 3%*, 10 +/- 1.4%* dagger (*P 相似文献   
114.
The assessment of the viral residual risk from blood products is an assessment indicator of the quality management system and of the availability process of these products. Assessments of HIV, HBV and HCV viruses transmission risks through blood transfusion are calculated after the setting of a quality approach at the Abidjan NBTC. The method used estimates the risk of a donation made during a period immunologically silent. The residual risks for HIV, HBV, and HCV viruses have been estimated by multiplying the incidence rate for 100,000 people per year by the respective durations of the serological windows. The data received from the Abidjan Center's information processing system (Progesa 4.4d of MAK SYSTEM) go from 2002 to 2004 period. The residual risks are 1/5780 donations for HIV and 1/406 donations for the HCV, then 1/383 donations for the HBV. The residual risk for the HIV is almost four times reduced compared to that of 1997. The results show not only the importance of the transmission risk of HIV, HBV and HCV viruses through blood products, but also the necessity to set a quality management system in endemic countries of Sub-Saharan Africa.  相似文献   
115.
Insect-borne diseases represent a worldwide threat. In addition to fight against vectors (insecticides) and disease prevention (vaccination against yellow fever, chemoprophylaxis against malaria), insect repellents applied on the skin could help reduce the heavy burden related to these diseases. In a field study performed in Senegal, we compared the efficacy of one skin application between 3 and 4 p.m. of four spray repellents [icaridine 20%, para-menthane-diol (PMD) 20% and 50% and DEET 50%] against placebo, among 100 healthy male and female volunteers experienced with mosquito capture. Double-blind randomized cross-over placebo-controlled study (Latin-square design) during five consecutive nights (7 p.m. to midnight) in two villages was conducted. To avoid residual effect, right or left leg was alternately exposed during consecutive nights and the exposed leg was washed before next night. The statistical model was random and mixed effects anova . All four active repellents provided a significant and similar protection compared with placebo, lasting 8 h. However, there was a non-significant trend for a higher protection by DEET 50% than by PMD 20% ( P  = 0.07). Duration of protection was similar for all repellents. Their effects were similar among men and women, and against Anopheles or other species. No serious adverse drug reaction was noticed. Using a rigorous methodology and a large number of volunteers, our well-controlled study demonstrated an important and similar protective effect of all four repellents compared with placebo. Such field studies should be required before approval of any newly developed repellent.  相似文献   
116.
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 [Ca(2+)] 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 K(ATP) 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 [Ca(2+)] loading, and infarct size. In addition they tested the potential role of the mitochondrial K(ATP) 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 microm 5-hydroxydecanoate (5-HD) from 5 min before until 5 min after sevoflurane (SPC + 5-HD). Cytosolic [Ca(2+)] 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 [Ca(2+)] and reduced contractility (dLVP/dt(max)), relaxation (diastolic LVP, dLVP/dt(min)), myocardial oxygen consumption (MvO(2)), and cardiac efficiency. In SPC hearts, cytosolic [Ca(2+)] overloading (especially diastolic [Ca(2+)]) was decreased with increased myocardial [Ca(2+)] influx (d[Ca(2+)]/dt(max)) and efflux (d[Ca(2+)]/dt(min)), improved contractility, relaxation, coronary flow, MvO(2), 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. CONCLUSIONS: Anesthetic preconditioning occurs after long-term hypothermic ischemia, and the infarct size reduction is the result, in part, of mitochondrial K(ATP) channel opening.  相似文献   
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Cadmium, due to its estrogen-like activity, has been suspected to increase the risk of breast cancer; however, epidemiological studies have reported inconsistent findings. We conducted a case–control study (4,059 cases and 4,059 matched controls) nested within the E3N French cohort study to estimate the risk of breast cancer associated with long-term exposure to airborne cadmium pollution, and its effect according to molecular subtype of breast cancer (estrogen receptor negative/positive [ER−/ER+] and progesterone receptor negative/positive [PR−/PR+]). Atmospheric exposure to cadmium was assessed using a Geographic Information System-based metric, which included subject's residence-to-cadmium source distance, wind direction, exposure duration and stack height. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using conditional logistic regression. Overall, there was no significant association between cumulative dose of airborne cadmium exposure and the risk of overall, premenopausal and postmenopausal breast cancer. However, by ER and PR status, inverse associations were observed for ER− (ORQ5 vs. Q1 = 0.63; 95% CI: 0.41–0.95, ptrend = 0.043) and for ER−/PR− breast tumors (ORQ4 vs. Q1 = 0.62; 95% CI: 0.40–0.95, ORQ5 vs. Q1 = 0.68; 95% CI: 0.42–1.07, ptrend = 0.088). Our study provides no evidence of an association between exposure to cadmium and risk of breast cancer overall but suggests that cadmium might be related to a decreased risk of ER− and ER−/PR− breast tumors. These observations and other possible effects linked to hormone receptor status warrant further investigations.  相似文献   
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Introduction

Although interventions to control HIV among high-risk groups such as female sex workers (FSW) are highly recommended in Africa, the contents and efficacy of these interventions are unclear. We therefore designed a comprehensive dedicated intervention targeting young FSW and assessed its impact on HIV incidence in Burkina Faso.

Methods

Between September 2009 and September 2011 we conducted a prospective, interventional cohort study of FSW aged 18 to 25 years in Ouagadougou, with quarterly follow-up for a maximum of 21 months. The intervention combined prevention and care within the same setting, consisting of peer-led education sessions, psychological support, sexually transmitted infections and HIV care, general routine health care and reproductive health services. At each visit, behavioural characteristics were collected and HIV, HSV-2 and pregnancy were tested. We compared the cohort HIV incidence with a modelled expected incidence in the study population in the absence of intervention, using data collected at the same time from FSW clients.

Results

The 321 HIV-uninfected FSW enrolled in the cohort completed 409 person-years of follow-up. No participant seroconverted for HIV during the study (0/409 person-years), whereas the expected modelled number of HIV infections were 5.05/409 person-years (95% CI, 5.01–5.08) or 1.23 infections per 100 person-years (p=0.005). This null incidence was related to a reduction in the number of regular partners and regular clients, and by an increase in consistent condom use with casual clients (adjusted odds ratio (aOR)=2.19; 95% CI, 1.16–4.14, p=0.01) and with regular clients (aOR=2.18; 95% CI, 1.26–3.76, p=0.005).

Conclusions

Combining peer-based prevention and care within the same setting markedly reduced the HIV incidence among young FSW in Burkina Faso, through reduced risky behaviours.  相似文献   
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