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The psoralens are secondary plant metabolites found in many fruits and vegetables. Synthetic forms of 5-methoxypsoralen (bergapten) and 8-methoxypsoralen (xanthotoxin) have been used in combination with UV radiation in skin photochemotherapy for decades. However, handling or ingestion of psoralen-containing plants as well as medicinal use of these compounds have been shown to cause human health hazards. We evaluated the subacute toxicity of bergapten and xanthotoxin in a mammalian model by mixing individual chemicals into mouse diet at 0, 250, and 1000 ppm, and in combination at 500 ppm each. Feeding on individual dietary treatments at 1000 ppm significantly reduced total liver cytochrome P450 (CYP) levels in female mice compared with the control diet, but not in males. However, combining the two chemicals resulted in a significant induction of total CYP450 in both males and females. Both the combined diet and bergapten at 250 ppm caused a weak induction of CYP1A1. Weight gain was significantly less in males fed either the combined or 1000 ppm diets, while only the combined diet induced a significant weight reduction in females compared with the control diet. The psoralens also caused hypertrophy of centrolobular hepatocytes in livers of treated animals in a manner consistent with morphological alterations seen in rodent livers exposed to liver CYP-inducing agents. Neither bergapten nor xanthotoxin, however, induced a significant dose-dependent toxicity in either male or female mice, suggesting that mice may not represent a good laboratory animal model for evaluating the toxicological effects of psoralens.  相似文献   
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Malaria is the world's most important parasitic infection with 500 millions cases annually and almost 2 millions death per year. This disease is more present in Sub-Saharan Africa where 90% of the infections are found. Artemisinin and its semi synthetic derivatives (artemether, artesunate) have actually the most powerful activity on malaria, even in its complicated forms and resistance cases.Various methods have been proposed for detection and quantification of artemisinin in Artemisia annua L. by HPLC-UV, but the plant extracts used for this quantification were extracts obtained with organic solvents (toluene, petroleum ether, hexane). To be able to use crude A. annua extracts prepared at low cost to formulate antipaludic drugs, we chose the use of a mixture of water and ethanol as solvent of extraction, but no adequate analytical method for this kind of extracts is published.The main objectives of this work were first to develop an analytical method for artemisinin quantification in hydro alcoholic extracts of A. annua. Second, this method had to be thoroughly validated by the research and development laboratory and, third, the transfer of this method to the routine laboratory had to be demonstrated. The final aim was to compare the estimation of measurement uncertainty obtained during the method validation with validation standards to measurement uncertainty estimates obtained during the method transfer study with real samples.The method was validated following the accuracy profile methodology and was found to be accurate in the concentration range of 10.0-54.0 μg/ml with CV < 8%. Limit of detection and of quantification were 2.73 and 10.0 μg/ml, respectively. The method was then successfully transferred to a laboratory in Benin by showing that the quality of the results that it will generate during routine application of the method is sufficient. Finally, the measurement uncertainty of the method was estimated from the validation experiments as well as from the transfer study with authentic unspiked samples of A. annua. The comparison of these measurement uncertainty estimations showed that they were coherent. It confirmed thus that the estimation of measurement uncertainty from validation experiments predicts well the measurement uncertainty of real routine samples. This analytical method was thus shown to be convenient for routine analysis of hydro alcoholic extracts of A. annua in Benin.  相似文献   
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The toxicity of arsenite to 8-cell stage hamster embryos was evaluated. Females were superovulated and mated; embryos were collected and grown for 72 h in culture medium containing vehicle control, 25, 50, 250, 500, or 750 nM arsenite. Morphological observations were taken at 0 and 24 h increments. A TUNEL assay was used for determining DNA damage. Survival was expressed by the ability to undergo zona escape. The control group had 78% survival and no evidence of deformities. Embryos in the 25, 50 and 250 nM groups had survival rates of 63%, 55% and 27%, respectively. Arsenite exposure caused total embryo lethality, major deformities, complete failure to undergo zona lysis, and significantly higher number of cells with fragmented DNA in embryos at the 500 and 750 nM concentrations. The study underscores the sensitivity of preimplantation stage embryos to the presence of even relatively small amounts of arsenic in luminal fluid.  相似文献   
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A double blind, randomized, controlled Phase 2 clinical trial was conducted to assess the safety, immunogenicity, and biologic impact of the vaccine candidate Apical Membrane Antigen 1-Combination 1 (AMA1-C1), adjuvanted with Alhydrogel®. Participants were healthy children 2–3 years old living in or near the village of Bancoumana, Mali. A total of 300 children received either the study vaccine or the comparator. No impact of vaccination was seen on the primary endpoint, the frequency of parasitemia measured as episodes >3000/μL/day at risk. There was a negative impact of vaccination on the hemoglobin level during clinical malaria, and mean incidence of hemoglobin <8.5 g/dL, in the direction of lower hemoglobin in the children who received AMA1-C1, although these differences were not significant after correction for multiple tests. These differences were not seen in the second year of transmission.  相似文献   
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Thiam S  LeFevre AM  Hane F  Ndiaye A  Ba F  Fielding KL  Ndir M  Lienhardt C 《JAMA》2007,297(4):380-386
Context  Poor adherence to treatment remains a major obstacle to efficient tuberculosis (TB) control in developing countries. Innovative strategies to improve access and adherence to treatment are needed. Objectives  To assess the effectiveness of a contextualized intervention strategy aimed at improving patients' adherence to treatment and to evaluate its impact on TB control in a resource-poor country in Africa with prevalent TB infection. Design, Setting, and Patients  A cluster randomized controlled trial, conducted between June 2003 and January 2005, at 16 government district health centers in Senegal. Patients older than 15 years with newly diagnosed sputum smear–positive pulmonary TB were randomly assigned to the intervention or control group. Intervention  The intervention strategy included reinforced counseling through improved communication between health personnel and patients, decentralization of treatment, choice of directly observed therapy (DOT) supporter by the patient, and reinforcement of supervision activities. In the control group, the usual TB control program procedures remained unchanged. Main Outcome Measure  Proportion of patients successfully completing the 8-month course of treatment and the proportion of patients defaulting from treatment. Results  A total of 1522 patients were recruited into the study. Treatment was successful for 682 (88%) of 778 patients recruited in the intervention group, and for 563 (76%) of 744 patients recruited in the control group (adjusted risk ratio [RR], 1.18; 95% confidence interval [CI], 1.03-1.34). The proportion of patients defaulting was reduced in the intervention group to 5.5% (n = 43) compared with 16.8% (n = 125) in the control group (adjusted RR, 0.43; 95% CI, 0.21-0.89). Conclusion  The intervention package based on improved patients counseling and communication, decentralization of treatment, patient choice of DOT supporter, and reinforcement of supervision activities led to improvement in patient outcomes compared with the usual TB control procedures. This approach may be generalized in the context of TB control programs in resource-poor countries. Trial Registration  clinicaltrials.gov Identifier: NCT00412009   相似文献   
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Background

No validated disease-specific questionnaires exist to capture health-related quality of life (HRQoL) in patients with Merkel cell carcinoma (MCC). The Functional Assessment of Cancer Therapy – Melanoma (FACT-M) is validated in patients with melanoma, which shares many similarities with MCC. This paper reports the psychometric properties of the FACT-M in the metastatic MCC population.

Methods

Data were collected as part of a single-arm, open-label, multicenter trial involving patients with metastatic MCC who had failed at least one previous line of chemotherapy. FACT-M and EQ-5D were administered at baseline, Week 7, Week 13, and Week 25. An optional interview was administered at the same time points. MCC-specific FACT-M scores were derived following a combined quantitative and qualitative approach. Reliability and construct validity of original and additional MCC-specific FACT-M scores were assessed at baseline. Capacity to detect change in tumor size was assessed from baseline to Week 7. Minimally important differences (MIDs) were computed using distribution and anchor-based methods.

Results

Baseline assessments were available in 70 patients (mean age: 70 years; 74.3% male); 19 patients were interviewed at baseline. Additional MCC-specific scores were as follows: Physical Function score (six items), Psychological Impact score (six items), and MCC summary score (12 items). FACT-M original and additional MCC-specific scores both demonstrated acceptable psychometric properties: high reliability (Cronbach’s alpha: 0.81–0.96), good convergent validity (correlations above 0.4 observed for 88% of items of the Melanoma surgery scale, 75% of items of the Melanoma scale, and 100% of items of the other FACT-M domains). Some evidence of floor/ceiling effects and poor discriminant ability was found. Higher scores (better HRQoL) on all FACT-M domains were observed in patients with better functioning (assessed by ECOG performance score), supporting clinical validity. Despite the small sample for responsiveness analysis (n =?37), the majority of FACT-M scores showed sensitivity to changes in tumor size at Week 7 with small to moderate effect sizes. MIDs were consistent with previously reported values in the literature for FACT-M domains.

Conclusions

FACT-M is suitable to capture HRQoL in patients with metastatic MCC, thus making it a potential candidate for assessing HRQoL in MCC trials.

Trial registration

This study is a post-hoc analysis conducted on data collected in Part A of the JAVELIN Merkel 200 trial. This trial was registered on 2 June 2014 with ClinicalTrials.gov as NCT02155647.
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Recent observations based on immunohistochemistry and RT-PCR demonstrate that early placenta insulin-like peptide (EPIL), encoded by the INSL4 gene, is present in the placenta during gestation. In the present study, we report on the development of a specific immunoassay, entirely based on two monoclonal anti-peptide antibodies (mAbs), and its use for the detection of pro-EPIL forms in biological fluids during pregnancy. One mAb directed against the C-connecting peptide was used to capture pro-EPIL forms and their binding was revealed by a radiolabeled anti-A chain mAb as the indicator. A composite synthetic peptide, encompassing the C- and A-domains, was utilized as the standard. Under these experimental conditions, the assay displays a sensitivity limit of 2 ng/mL. Pro-EPIL molecular forms were detected in both amniotic fluid and maternal serum of pregnant women. At 12 to 16 weeks of pregnancy, the pro-EPIL level was higher in amniotic fluid (246 +/- 50.8 ng/mL) than in maternal serum (5 +/- 2.0 ng/mL). As gestation advanced, so the concentration of pro-EPIL forms decreased in amniotic fluid while its level increased in maternal serum. Interestingly, in amniotic fluid, the pattern of pro-EPIL concentration during pregnancy is very similar to that observed for human chorionic gonadotropin (hCG) and its free subunits. The pattern of serum pro-EPIL concentration is similar to that of the free alpha-subunit. Together with our previous immunohistochemical observations, these results indicate that pro-EPIL is preferentially secreted by cytotrophoblasts in amniotic fluid and that the biosynthesis of hCG subunits and EPIL may be regulated by common pathways. Overall, our observations strongly suggest that EPIL may play a critical physiological role during embryonic and foetal development.  相似文献   
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