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Invasion of the deer ked (Lipoptena cervi), an ectoparasitic fly commonly found in cervids, has been rapid in Finland during the last four decades. As the distribution area of this species has expanded from the south towards the northern latitudes, the associated problems have become more evident. Various animals such as horses, cattle and especially reindeer have been reported to host this parasite. Moreover, in certain areas, the deer ked causes major inconveniences for humans potentially limiting recreational activities in forests. We wanted to study if deer ked parasitism and intensity of the infection in winter time could be detected by using visual examination of the snow on cervid bedding sites and by analysing biotic samples found from the bedding sites. Our results demonstrate that chronic deer ked infection causes reddish-brown snow discolouration (host tissue fluid and deer ked faeces) on the bedding sites to the extent that parasitism can be diagnosed. Hence, we suggest that deer ked infection prevalence and range expansion could be rapidly monitored using our new practical and reliable method. In the future, bedding site analyses will likely be useful in predicting and potentially preventing the negative effects of this ecologically and socio-economically important parasite.  相似文献   
43.
Carcinoma cell invasion is traditionally studied in three-dimensional organotypic models composed of type I collagen and fibroblasts. However, carcinoma cell behavior is affected by the various cell types and the extracellular matrix (ECM) in the tumor microenvironment. In this study, a novel organotypic model based on human uterine leiomyoma tissue was established and characterized to create a more authentic environment for carcinoma cells. Human tongue squamous cell carcinoma cells (HSC-3) were cultured on top of either collagen or myoma. Organotypic sections were examined by immunohistochemistry and in situ hybridization. The maximal invasion depth of HSC-3 cells was markedly increased in myomas compared with collagen. In myomas, various cell types and ECM components were present, and the HSC-3 cells only expressed ECM molecules in the myoma model. Organotypic media were analyzed by radioimmunoassay, zymography, or Western blotting. During carcinoma cell invasion, matrix metalloprotease-9 production and collagen degradation were enhanced particularly in the myoma model. To evaluate the general applicability of the myoma model, several oral carcinoma, breast carcinoma, and melanoma cell lines were cultured on myomas and found to invade in highly distinct patterns. We conclude that myoma tissue mimics the native tumor microenvironment better than previous organotypic models and possibly enhances epithelial-to-mesenchymal transition. Thus, the myoma model provides a promising tool for analyzing the behavior of carcinoma cells.Tumor growth and invasion are not just determined by the malignant tumor cells, but instead various cell types and the extracellular matrix (ECM) of the tumor microenvironment affect the outcome.1 Particularly, fibroblasts have many prominent roles in the cancer progression. In fact, in many carcinomas, the majority of the stromal cells are fibroblasts that possess myofibroblastic characteristics and are called cancer-associated fibroblasts. They produce ECM molecules, proteases, growth factors, and chemokines that crucially affect the carcinoma cell behavior.2,3 In this context, the organotypic three-dimensional skin model developed by Fusenig et al4 replicates the in vivo situation more closely in vitro than the two-dimensional cell culture experiments. The model allows studying of carcinoma cell invasion in three-dimensional collagen gel embedded with fibroblasts. The degree of invasion can also be quantitatively analyzed.5,6 However, this kind of organotypic model remains somewhat artificial due to the lack of other cell types besides fibroblasts and ECM components that are present in vivo. In addition to the carcinoma cells and fibroblasts, endothelial and inflammatory cells, as well as several ECM molecules, are known to contribute to the tumor growth. The induction of angiogenesis, recruitment of inflammatory cells, and increased turnover of ECM components result in tumor progression.7,8 Therefore, we wished to determine whether real human tissue can be used in the organotypic method to provide a more natural stroma-like environment for studying carcinoma cell invasion. We used uterine leiomyoma tissue, which mainly consists of smooth muscle actin (SMA)-positive cells and collagens.9 The existence of various additional cell types and proteins in the myoma tissue was characterized, and the invasiveness of malignant human tongue squamous cell carcinoma cells (HSC-3) into this novel myoma organotypic culture was measured by different methods and compared with the traditional collagen organotypic model. To test the general applicability of the myoma model, the invasion patterns of various cell lines were examined in myoma and collagen organotypic cultures.  相似文献   
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The recovery process following cerebral insults such as stroke is affected by aging and pharmacotherapy. The use of medication including CNS-active drugs has increased in the elderly during recent years. However, surprisingly little is known about how safe they are with respect to severity of sensorimotor and cognitive impairments or recovery of function following possible cerebrovascular accidents. This review examines the experimental and clinical literature, primarily from 1995 onwards, concerning medication in relation to cerebrovascular events and functional recovery. Special attention is directed to polypharmacy and to new CNS-active drugs, which the elderly are already taking or are prescribed to treat emerging, stroke-induced psychiatric symptoms. The neurobiological mechanisms affected by these drugs are discussed.  相似文献   
46.
The biopsy specimens from the primary tumors of 234 women with axillary-lymph-node-positive breast carcinomas (followed up for a mean of 10.9 years) were subjected to interactive morphometric analysis of nine nuclear factors. The proliferative activity of the tumors was estimated by determining two different mitotic indices. Morphometrically determined nuclear factors and mitotic indices showed a significant correlation to the histological grading (p less than 0.0001). Mitotic activity index (MAI; p = 0.018) and volume-corrected mitotic index (M/V index; p = 0.005) accurately predicted the tumor recurrence. Recurrence-free survival was related to the M/V index (p = 0.0003), MAI (p = 0.0024) and tumor size (p = 0.0144). Disease-related survival was determined by the tumor size (p less than 0.0001), M/V index (p = 0.0142) and MAI (p = 0.0492) in that order. On the other hand, the nuclear factors analyzed and the histological grading used had no predictive value (i.e. tumor recurrence, recurrence-free survival or tumor-related survival) in these women. The results indicate that mitotic indices can be successfully applied in place for subjective grading and nuclear morphometry in predicting the disease outcome in patients with axillary-lymph-node-positive breast carcinomas. The mitotic indices provide independent prognostic information in addition to tumor size. The major clinical implications of these results would be to accurately disclose among these women the high-risk patients (i.e. those with high mitotic indices), who might benefit from more agressive adjuvant therapies.  相似文献   
47.
Macrophage mannose receptor on lymphatics controls cell trafficking   总被引:2,自引:0,他引:2  
Macrophage mannose receptor (MR) participates in pathogen recognition, clearance of endogenous serum glycoproteins, and antigen presentation. MR is also present on lymphatic vessels, where its function is unknown. Here we show that migration of lymphocytes from the skin into the draining lymph nodes through the afferent lymphatics is reduced in MR-deficient mice, while the structure of lymphatic vasculature remains normal in these animals. Moreover, in a tumor model the primary tumors grow significantly bigger in MR–/– mice than in the wild-type (WT) controls, whereas the regional lymph node metastases are markedly smaller. Adhesion of both normal lymphocytes and tumor cells to lymphatic vessels is significantly decreased in MR-deficient mice. The ability of macrophages to present tumor antigens is indistinguishable between the 2 genotypes. Thus, MR on lymphatic endothelial cells is involved in leukocyte trafficking and contributes to the metastatic behavior of cancer cells. Blocking of MR may provide a new approach to controlling inflammation and cancer metastasis by targeting the lymphatic vasculature.  相似文献   
48.
Mifepristone is a potent antiglucocorticoid, the administration of which results in a dose-dependent activation of the hypothalamic-pituitary-adrenal axis. However, the net effect of this compound on circulating glucocorticoid activity is not known. We have used a recombinant cell bioassay to study glucocorticoid bioactivity (GBA), measured directly from serum, in 18 women undergoing medical termination of an early pregnancy with 200 mg mifepristone, followed by 0.8 mg misoprostol, a prostaglandin. Increased serum mifepristone was accompanied by an increase in serum cortisol that was insufficient to maintain circulating GBA within the normal (pre-mifepristone) range (34.7-93.8 nM cortisol equivalents); after approximately 43, 46, and 68 h of mifepristone ingestion, the mean serum GBA levels were much lower than the mean pre-mifepristone level (P < 0.0001). At the corresponding times, 16, 13, and 12 women displayed subnormal serum GBA levels (ranges, <15.6-23, <15.6-25.6, and <15.6-32.5 nM cortisol equivalents, respectively). Altogether 11 subjects displayed subnormal serum GBA (range, <15.6-32.5 nM cortisol equivalents) continuously in the presence of high concentrations of mifepristone. Two weeks after mifepristone administration, circulating GBA had returned to normal levels in all subjects. We conclude that 200 mg mifepristone elicits a significant suppression of serum GBA, to one third of the pretreatment value, despite the compensatory increase in the serum cortisol concentration.  相似文献   
49.
Title. A disaster preparedness and response project in Afghanistan: participants' perceptions. Aim. This paper is a report of a study to describe Emergency Mobile Unit team members’ and healthcare professionals’ perceptions of a disaster preparedness and response project and to explore the elements of participation that could support its sustainability. Background. Many developing countries have limited preparedness for disaster response. There is a need to better understand the role of national and local participation, and their interplay. We also need to consider the moderation and eventual planned withdrawal of international humanitarian organizations’ support. Afghanistan is one example of a country in postdisaster development where the opportunity arose for an in‐depth study of disaster preparedness and response. Method. Data were collected in Finland and Afghanistan in 2004 using an ethnographic approach, with seven thematic interviews (n = 8) and two focus groups (n = 7). The participants were Afghan healthcare professionals and expatriates who had facilitated Emergency Mobile Unit training. Findings. Constraints in the project arose from uncoordinated implementation and poor job satisfaction, in addition to intrinsic characteristics of the situation. A second theme to emerge was that participation was a positive response to health emergencies. Thirdly, a need for further development and overall support for Emergency Mobile Units was clearly evident. Conclusion. Improved coordination and measures to increase job satisfaction for national aid workers are needed, and a more positive knowledge‐based response system and continued overall support for emergency mobile teams. Involving disaster‐affected people and the local community, especially women, in health development projects will help to ensure both success and sustainability.  相似文献   
50.
Semicarbazide-sensitive amine oxidases (SSAO) are enzymes that are capable of deaminating primary amines to produce aldehyde, ammonia, and hydrogen peroxide. This activity has been associated with vascular adhesion protein-1 (VAP-1) and is found in the serum, endothelium, adipose, and smooth muscle of mammals. Circulating SSAO activity is increased in congestive heart failure, diabetes, and inflammatory liver diseases. To investigate the origin of circulating SSAO activity, two transgenic mouse models were created with full-length human VAP-1 (hVAP-1) expressed on either endothelial (mTIEhVAP-1) or adipose tissues (aP2hVAP-1), with tie-1 and adipocyte P2 promoters, respectively. Under normal conditions a circulating form of hVAP-1 was found at high levels in the serum of mice with endothelium-specific expression and at low levels in the serum of mice with adipose specific expression. The level of circulating hVAP-1 in the transgenic mice varied with gender, transgene zygosity, diabetes, and fasting. Serum SSAO activity was absent from VAP-1 knockout mice and endothelial cell-specific expression of human VAP-1 restored SSAO activity to the serum of VAP-1 knockout mice. Together, these experiments show that in the mouse VAP-1 is the only source of serum SSAO, that under physiological conditions vascular endothelial cells can be a major source of circulating VAP-1 protein and SSAO, and that serum VAP-1 can originate from both endothelial cells and adipocytes during experimental diabetes. An increased endothelial cell capacity for lymphocyte binding and altered expression of redox-sensitive proteins was also associated with the mTIEhVAP-1 transgene.  相似文献   
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