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141.
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In a previous article we reported that mutations favoring cancer at adulthood seemed to improve fertility and limit miscarriages. Because spontaneous abortion may result from anomalies in embryo, we questioned if an increased frequency of congenital malformation could be evidenced among cancer-prone families. Oncogenetics database (≈193 000 members) of the comprehensive cancer center Jean Perrin was crossed with regional registry of congenital malformations (≈10 000). Among children born between 1986 and 2011, 176 children with malformation matched in both databases. In breast/ovaries cancer-prone families, the risk for malformations was multiplied by 2.4 [1.2-4.5] in case of a BRCA1 mutation. Frequencies of malformation in BRCA2 and MMR mutated families were similar to families without a cancer syndrome. In comparison to malformations concerning a unique anatomical system, multimalformations were significantly more frequent in case of BRCA or MMR mutations: compared to families without cancer syndrome, the risk of multimalformations was multiplied by 4.1 [0.8-21.7] for cancer-prone families but with no known deleterious mutation, by 6.9 [1.2-38.6] in families with a known mutation but an unknown parental mutational status and by 10.4 [2.3-46.0] when one parent carried the familial mutation. No association with the type of anatomical system was found, nor with multiple births. These results suggest that BRCA and MMR genes play an important role in human embryogenesis and that if their function is lowered because of heterozygote mutations, congenital malformations are either more likely (BRCA1 mutations) and/or more susceptible to concern several anatomical systems.  相似文献   
143.
The supramammillary nucleus (SuM) has an emerging role in appetite control. We have shown that the rat SuM is activated during hunger or food anticipation, or by ghrelin administration. In the present study, we characterised the connectivity between the SuM and key appetite‐ and motivation‐related nuclei in the rat. In adult wild‐type rats, or rats expressing Cre recombinase under the control of the tyrosine hydroxylase (TH) promoter (TH‐Cre rats), we used c‐Fos immunohistochemistry to visualise and correlate the activation of medial SuM (SuMM) with activation in the lateral hypothalamic area (LH), the dorsomedial hypothalamus (DMH) or the ventral tegmental area (VTA) after voluntary consumption of a high‐sugar, high‐fat food. To determine neuroanatomical connectivity, we used retrograde and anterograde tracing methods to specifically investigate the neuronal inputs and outputs of the SuMM. After consumption of the food there were positive correlations between c‐Fos expression in the SuMM and the LH, DMH and VTA (P = 0.0001, 0.01 and 0.004). Using Fluoro‐Ruby as a retrograde tracer, we demonstrate the existence of inputs from the LH, DMH, VTA and ventromedial hypothalamus (VMH) to the SuMM. The SuMM showed reciprocal inputs to the LH and DMH, and we identified a TH‐positive output from SuMM to DMH. We co‐labelled retrogradely‐labelled sections for TH in the VMH, or for TH, orexin and melanin‐concentrating hormone in the LH and DMH. However, we did not observe any colocalisation of immunoreactivity with any retrogradely‐labelled cells. Viral mapping in TH‐Cre rats confirms the existence of a reciprocal SuMM‐DMH connection and shows that TH‐positive cells project from the SuMM and VTA to the lateral septal area and cingulate cortex, respectively. These data provide evidence for the connectivity of the SuMM to brain regions involved in appetite control, and form the foundation for functional and behavioural studies aiming to further characterise the brain circuitry controlling eating behaviours.  相似文献   
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Objective Analysis of risk factors associated with severity in patients with confirmed leptospirosis. Design and setting Retrospective study in 147 leptospirosis-confirmed patients at two tertiary nonteaching hospital in Reunion Island. Patients 138 men and 9 women, aged 36 ± 14 years, 80 in the ICU and 67 in medical wards. Measurements and results We collected demographic, clinical, biological, and radiographic data and performed univariate and multivariate analysis to examine risk factors associated with admission in ICU and mortality. Pulmonary forms were more frequent (85%) than in previous reports, with 85 cases (65.3%) on abnormal chest radiography. Among the 38 patients who underwent bronchoalveolar lavage at admission 31 (81.5%) had alveolar hemorrhage. Independent factors related to ICU admission were: age over 46 years (OR 3.02), creatinine higher than 200 μmol/l (6.69), shock (13.87), and acute respiratory failure (20.69). Mortality was 12.9%. The only factor independently related to mortality was need for mechanical ventilation (OR 20.94). Icterohemorrhagiae serogroup was found in 62 cases (42.8%) but was not related to death. Conclusions Pulmonary involvement is a major feature in leptospirosis disease but is not associated with poor outcome. Identification of clinical and laboratory findings on admission may help to better characterize severe cases. Mailing address: Arnaud Bourdin is currently at the Service de Pneumologie, CHU Montpellier, France.  相似文献   
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The accuracy of ST/heart rate (ST HR) index was evaluated in patients presenting for exercise electrocardiography with suspected coronary disease. In all, 420 patients (235 men and 185 women) with normal electrocardiograms at rest underwent exercise testing, followed within 3 months by coronary angiography. The sensitivity and specificity for standard ST criteria (greater than or equal to 1 mm horizontal or downsloping depression) were 48% (78 of 162) and 81% (208 of 258), respectively. An ST HR-index threshold of 1.86 microV/beta/min had the exact same specificity with a sensitivity of 44% (71 of 162; p = not significant). Consideration of greater than or equal to 1.5 mm upsloping depression had no significant impact on the aforementioned results. Using multivariate logistic regression analysis, age, sex, symptoms, cigarette smoking, diabetes mellitus, qualitative ST slope, rate-pressure product, METs achieved and exercise angina were evaluated with and without ST HR index and ST depression. According to this analysis, age, sex, symptoms and ST slope were good predictors of presence or absence of disease. Neither ST HR index nor ST depression had significance in the multivariate analysis. However, when a separate analysis was performed in men and women, the 2 quantitative ST variables showed significance in men, but not in women. Comparisons of discriminative accuracy using receiver-operating characteristic curves demonstrated differences between men and women, but no difference between ST HR index and ST depression. Therefore, concerning questions of coronary disease diagnosis, consideration of ST HR index was not better than standard ST criteria, and added nothing to multivariate analysis of other available variables.  相似文献   
149.

Aim of the study

In a search for new plant-derived biologically active compounds against malaria parasites, we have carried out an ethnopharmacological study to evaluate the susceptibility of cultured Plasmodium falciparum to extracts and fractions from seven Cameroonian medicinal plants used in malaria treatment. We have also explored the inhibition of the Plasmodium falciparum cysteine protease Falcipain-2.

Materials and methods

Plant materials were extracted by maceration in organic solvents, and subsequently partitioned or fractionated to afford test fractions. The susceptibility of erythrocytes and the W2 strain of Plasmodium falciparum to plant extracts was evaluated in culture. In addition, the ability of annonaceous extracts to inhibit recombinant cysteine protease Falcipain-2 was also assessed.

Results and discussion

The extracts showed no toxicity against erythrocytes. The majority of plant extracts were highly active against Plasmodium falciparumin vitro, with IC50 values lower than 5 μg/ml. Annonaceous extracts (acetogenin-rich fractions and interface precipitates) exhibited the highest potency. Some of these extracts exhibited modest inhibition of Falcipain-2.

Conclusion

These results support continued investigation of components of traditional medicines as potential new antimalarial agents.  相似文献   
150.
BACKGROUND: Allografts are occasionally accepted in the absence of immunosuppression. Because naturally occurring CD4(+)CD25(+) regulatory T cells (natural CD25(+) Treg cells) have been shown to inhibit allograft rejection, we investigated their influence on the outcome of allografts in nonimmunosuppressed mouse recipients. METHODS: We compared survival times of male CBA/Ca skin grafts in female CBA/Ca recipients expressing a transgenic anti-HY T-cell receptor on a RAG-1(+/+) (A1[M]RAG+) or a RAG-1(-/-) (A1[M]RAG-) background. Depletion of natural CD25(+) Treg cells in A1[M]RAG+ mice was achieved by in vivo administration of the PC61 monoclonal antibody. The influence of natural CD25(+) Treg cells on the fate of major histocompatibility complex class II-mismatched (C57BL/6X bm12)F1 skin or bm12 heart transplants in C57BL/6 recipients was also assessed. Finally, we investigated the impact of natural CD25(+) Treg cells on the production of T-helper (Th)1 and Th2 cytokines in mixed lymphocyte cultures between C57BL/6 CD4(+) CD25(-) T cells as responders and bm12 or (C57BL/6X bm12)F1 antigen-presenting cells as stimulators. RESULTS: Male allografts were spontaneously accepted by female A1(M)RAG+ mice but readily rejected by female A1(M)RAG+ mice depleted of natural CD25(+) Treg cells by pretreatment with the PC61 monoclonal antibody. Depletion of CD25(+) Treg cells also enhanced eosinophil-determined rejection of (C57BL/6X bm12)F1 skin grafts or bm12 cardiac grafts in C57BL/6 recipients. Finally, natural CD25(+) Treg cells inhibited the production of interleukin (IL)-2, interferon-gamma, IL-5, and IL-13 in mixed lymphocyte culture in a dose-dependent manner. CONCLUSION: Natural CD25(+) Treg cells control Th1- and Th2-type allohelper T-cell responses and thereby influence the fate of allografts in nonimmunosuppressed recipients.  相似文献   
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