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A longitudinal study of semen quality in pesticide spraying danish farmers   总被引:9,自引:0,他引:9  
It was hypothesized that occupational exposure to pesticides during a spraying season causes changes in semen quality that might be detected in a longitudinal study. We analyzed the within-person changes in semen quality and reproductive hormones across a spraying season in groups of farmers using and not using pesticides. A total of 248 men collected two semen samples (participation rate: 32%). The median sperm concentration declined significantly from the first to the second sample in both groups, but there was no statistical difference in the decline between the two groups, unadjusted or adjusted. Only minor changes were found in sperm morphology, vitality, motility, sperm chromatin denaturation (SCSA), and reproductive hormones, and the differences in changes between the two groups were nonsignificant, or, in the opposite direction to the expected. There was no relation between the changes in sperm parameters in relation to pesticide exposure variables. In conclusion, use of pesticides by Danish farmers is not a likely cause of short-term effects on semen quality and reproductive hormones.  相似文献   
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The hepatocyte growth factor (HGF) has been crucially implicated in the development of proliferative retinal diseases; however, it is unclear whether retinal glial cells express or respond to HGF. Therefore, we examined the expression of HGF and of the receptor for HGF, c-Met, by immunohistochemical costaining with glial fibrillary acidic protein (GFAP) in epiretinal membranes of patients with proliferative vitreoretinopathy (PVR) and proliferative diabetic retinopathy (PDR), respectively. Furthermore, it was determined whether cells of the human retinal glial cell line, MIO-M1, secrete HGF protein, and whether HGF stimulates proliferation and chemotaxis, and secretion of the vascular endothelial growth factor (VEGF). Neuroretinas of patients with PVR express elevated mRNA level for HGF in comparison to control retinas. In epiretinal membranes of patients with PVR or PDR, immunoreactivity for HGF and for c-Met, respectively, partially colocalized with immunoreactivity for GFAP. Fetal bovine serum and basic fibroblast growth factor, but not heparin-binding epidermal or platelet-derived growth factors, evoked HGF secretion by cultured retinal glial cells. HGF displayed only a marginal effect on cell proliferation while it stimulated chemotaxis. HGF promoted the secretion of VEGF, via activation of the phosphatidylinositol-3 kinase. It is concluded that glial cells in epiretinal membranes express both HGF protein and c-Met receptors. The results suggest an autocrine/paracrine role of HGF in glial cell responses during proliferative vitreoretinal disorders as well as in retinal neovascularization, by stimulating of VEGF release.  相似文献   
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In this study, a specific monoclonal antibody was used to immunohistochemically investigate correlated expression of the cell cycle promoter cyclin E and the proliferation marker Ki-67 in benign extravillous trophoblast and gestational trophoblastic lesions. Our data show that cyclin E is expressed in the normal extravillous trophoblast, with strongest levels of expression in the cell columns of anchoring villi. Differences could be observed in expression of Ki-67 in both normal extravillous trophoblast and gestational trophoblastic lesions. In the extravillous trophoblast of the cell columns, expression of cyclin E started more distal compared with Ki-67 and was maintained (with less intensity) into the deeper layers of interstitial trophoblast. In the benign trophoblastic lesions (exaggerated placental site [EPS] and placental site nodule [PSN]) and in the trophoblast proliferations on the surface of hydropic villi of hydatidiform moles (HM), the percentage of cells expressing cyclin E was higher than of those expressing Ki-67. The same observation could be made for a case of placental site trophoblastic tumor (PSTT). In contrast, choriocarcinomas (N=8), which are definitely malignant tumors, showed an opposite pattern, with a much higher percentage of strongly Ki-67-positive cells compared with cyclin E-positive cells. We conclude that cyclin E is expressed in benign extravillous trophoblast and gestational trophoblastic lesions, where a ratio cyclin E/Ki-67<1 characterizes choriocarcinomas, whereas PSTT and the benign lesions (HM, EPS, PSN) show expression of cyclin E in a higher percentage of cells than Ki-67 (cyclin E/Ki-67 ratio >1).  相似文献   
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Tumor cells have the ability to exploit stromal cells to facilitate metastasis. By using malignant melanoma as a model, we show that the stroma adjacent to metastatic lesions is enriched in the known metastasis-promoting protein S100A4. S100A4 stimulates cancer cells to secrete paracrine factors, such as inflammatory cytokines IL8, CCL2 and SAA, which activate stromal cells (endothelial cells and monocytes) so that they acquire tumor-supportive properties. Our data establishes S100A4 as an inducer of a cytokine network enabling tumor cells to engage angiogenic and inflammatory stromal cells, which might contribute to pro-metastatic activity of S100A4.  相似文献   
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Background: To obtain more co-ordinated services, better co-operation between the services and more efficient use of resources, a pilot project for transferring some district psychiatric centres (DPCs) to large municipalities is planned by the Norwegian government. Systematic knowledge about the patients involved is needed when clinical needs and standards, funding, and political agendas are discussed. This study identifies the clinical, socio-demographic, and behavioural characteristics of patients who need services from both the municipality and the DPC.

Method: A national mapping of patients in specialist mental health services was conducted in 2012/2013, including 65% of all inpatients (n?=?2358) and 60% of all outpatients (n?=?23?124). The need for services was assessed by each patient’s clinician.

Results: It was found that 74% of inpatients and 43% of outpatients needed one or more services from the municipality, usually involving housing, mental health treatment/therapy, or economic support according to their clinicians. These were typically patients with severe mental illness, young inpatients, older outpatients and persons with low education and weak social networks. Only small differences in the need for municipal services were found between patients in hospitals and DPCs.

Conclusions: Many of the patients in specialist mental health services, especially the inpatients, needed services from municipal social and health services. Because these patients had the most severe mental illnesses and were the most socially deprived, a stronger integration of service levels would potentially benefit these patients most. The pilot project should be evaluated to identify the consequences for patients, staff, quality of services, and costs of transferring services to a lower system level.  相似文献   
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