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81.
Fibroblast growth factor 2 induces differentiation and apoptosis of Askin tumour cells 总被引:7,自引:0,他引:7
Kim MS Kim CJ Jung HS Seo MR Juhnn YS Shin HY Ahn HS Thiele CJ Chi JG 《The Journal of pathology》2004,202(1):103-112
Peripheral primitive neuroectodermal tumour (PNET)/Ewing's sarcoma (ES) and neuroblastoma (NB) are related tumours of neural crest origin with primitive neural characteristics. Fibroblast growth factor 2 (FGF2) is a critical signalling molecule for primitive neural crest cells. The treatment of NB cells with FGF2 variably affects biological characteristics such as growth and differentiation, while in PNET/ES, FGF2 predominantly induces apoptosis. The JK-GMS Askin tumour cell line can be induced to differentiate upon treatment with nerve growth factor (NGF), indicating the integrity of the cellular machinery necessary for differentiation. The present study assesses whether FGF2 can induce differentiation in JK-GMS cells. JK-GMS cells expressed high-affinity FGF receptors (FGFRs), and treatment with FGF2 induced phosphorylation of FGFR1 together with activation of extracellular signal-regulated kinases (ERK1/ERK2) and c-Jun N-terminal kinase (JNK). Subsequent biological effects were growth inhibition, neuronal differentiation, and apoptosis, and these changes were associated with increased expression of neurofilaments, reduction of c-myc and bcl-2 expression, and activation of caspase 3. Treatment of the cells with a specific inhibitor of the MAPK/extracellular signal-regulated kinase (MEK)-1, PD98059, predominantly inhibited the effects of FGF2 on growth, differentiation, and apoptosis, while an inhibitor of JNK reduced apoptosis, indicating that the ERK1/2 and JNK pathways are critical components of FGF2-mediated effects in JK-GMS cells. Additional comparative analyses of FGF2-mediated effects in two ES cell lines (CADO-ES, RD-ES) and a PNET cell line (SK-N-MC) showed pronounced differentiation in SK-N-MC, but not in CADO-ES or RD-ES cells. This study demonstrates that FGF2 can induce neuronal differentiation of PNET including Askin tumour. These findings clearly indicate that the FGF2-mediated signalling pathway plays a critical role in controlling the major properties of PNET cells and may provide a potential therapeutic target for PNET. 相似文献
82.
83.
Mendonça EA Haas J Shagina L Larson E Friedman C 《Journal of biomedical informatics》2005,38(4):314-321
Natural language processing (NLP) is critical for improvement of the healthcare process because it can encode clinical data in patient documents. Many clinical applications such as decision support require coded data to function appropriately. However, in order to be applicable for healthcare, performance must be adequate. A valuable automated application is the detection of infectious diseases, such as surveillance of pneumonia in newborns (e.g., neonates) because the disease produces significant rates of morbidity and mortality, and manual surveillance is challenging. Studies have demonstrated that automated surveillance using NLP is a useful adjunct to manual surveillance and an effective tool for infection control practitioners. This paper presents a study evaluating the feasibility of an NLP-based monitoring system to screen for healthcare-associated pneumonia in neonates. We estimated sensitivity, specificity, and positive predictive value by comparing results with clinicians' judgments. Sensitivity was 71% and specificity was 99%. Our results demonstrated that the automated method was feasible. 相似文献
84.
Nesting behavior was found to differ for animals of five different inbred strains ofMus musculus reared in the same environment, indicating heritable differences in level of nesting byMus. For two separate crosses, hybrid animals built larger nests than did animals of the inbred parental strains. In addition, from data of one of the crosses and derived generations, a very low heritability of nesting but substantial dominance variance were found. This pattern of results is expected of characters which have been the target of natural selection. MaleMus were found to build larger nests than females of all groups tested. These findings suggest that nesting byMus musculus represents required thermoregulatory behavior.This research was supported by NSF grant GU 2591 and HEW grant NS 09536. 相似文献
85.
Medical terminologies are critical for automated healthcare systems. Some terminologies, such as the UMLS and SNOMED are comprehensive, whereas others specialize in limited domains (i.e., BIRADS) or are developed for specific applications. An important feature of a terminology is comprehensive coverage of relevant clinical terms and ease of use by users, which include computerized applications. We have developed a method for facilitating vocabulary development and maintenance that is based on utilization of natural language processing to mine large collections of clinical reports in order to obtain information on terminology as expressed by physicians. Once the reports are processed and the terms structured and collected into an XML representational schema, it is possible to determine information about terms, such as frequency of occurrence, compositionality, relations to other terms (such as modifiers), and correspondence to a controlled vocabulary. This paper describes the method and discusses how it can be used as a tool to help vocabulary builders navigate through the terms physicians use, visualize their relations to other terms via a flexible viewer, and determine their correspondence to a controlled vocabulary. 相似文献
86.
Evaluating a mental health assessment for older people with depressive symptoms in general practice: a randomised controlled trial. 总被引:1,自引:0,他引:1
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Antony J Arthur Carol Jagger James Lindesay Ruth J Matthews 《The British journal of general practice》2002,52(476):202-207
BACKGROUND: There is a lack of evidence on the most effective primary care management of older people with minor depression. AIM: To evaluate a follow-up assessment by the community mental health team (CMHT) for older people with depressive symptoms identified by practice nurses at a health check for people over the age of 75 years. DESIGN OF STUDY: A pragmatic randomised controlled trial. SETTING: A single large general practice in Leicestershire. METHOD: Patients receiving a health check administered by a practice nurse and scoring 5 or more on the 15-item Geriatric Depression Scale (GDS15) were randomised to either follow-up by the CMHT or routine general practitioner (GP) care. The GDS15 score was measured at the subsequent health check 18 months later. RESULTS: Forty-seven patients were randomised to CMHT assessment and 46 to routine GP care. Uptake of the intervention was 72% (n = 34). At the follow-up health check a greater proportion of the control group had improved GDS15 scores (P = 0.08). Following assessment, the CMHT recommended their further involvement in the care of 12 patients and this was authorised by patients' GPs in six cases. CONCLUSIONS: A follow-up mental health assessment by a member of the local CMHT was not effective in improving outcomes for mildly depressed older people. Other than random error possible reasons for this include the length of follow-up and a failure to meet raised expectations among the intervention group. If complex referral procedures do not improve outcomes for this group, then specialist community services should play a more prominent part in the training of practice staff to care for their depressed older patients. 相似文献
87.
Donor inseminations (DI) have been performed for decades. Most of the publications on this topic deal only with problems of tolerance and acceptance of this treatment for sterility. We already reported on them in parts I and II. In the present third and last part, we discuss the indications for DI: male infertility, genetic disorders, and unsuccessful assisted reproduction therapy. Which conditions do affect the success of therapy? Which methods are recommended? Our treatment results verify realistically that in effect DI only produces the desired child in about 50 % of the couples. As a complementary therapy, in vitro fertilization (IVF) with donor spermatozoa offers a real chance for pregnancy even for women whose husbands are infertile and who themselves suffer from impaired fertility such as pathological conditions of the fallopian tube or when simple inseminations have not resulted in pregnancy. After receiving consent from the State Physicians’ Chamber, we treated 19 women by donor IVF in our group practice and fulfilled their desire to bear their own child. 相似文献
88.
Zonal distribution of glomerular collapse in renal allografts: possible role of vascular changes 总被引:5,自引:0,他引:5
Collapsing glomerulopathy (CG), an aggressive variant of focal segmental glomerular sclerosis, is a renal disease with severe proteinuria and rapidly progressive renal failure. The pathogenesis of CG is unknown. It strongly resembles human immunodeficiency virus (HIV)-associated nephropathy, but the patients are HIV negative. The characteristic glomerular lesion is capillary loop collapse with prominent podocytes filling Bowman's space. Interestingly, these glomerular changes are usually associated with severe tubulointerstitial injury, including tubular epithelial degenerative changes, microcystic dilation of several tubules, and interstitial inflammatory cell infiltrate. Recently, it became evident that the morphologic pattern of CG may appear not only in native kidneys, but also de novo in renal allografts, and that the pattern of CG in renal transplants is not always associated with severe proteinuria. Studies describing CG in renal allografts are all based on biopsies. We report 3 allograft nephrectomy specimens that showed a zonal distribution of the characteristic collapsing glomerular changes with associated tubulointerstitial injury. All 3 kidneys had obliterative vascular changes. One nephrectomy specimen had chronic obliterative transplant arteriopathy, 1 had acute vascular rejection, and 1 had thrombotic microangiopathy. None of the patients had severe proteinuria. Our cases suggest that the morphologic pattern of CG in renal allografts may not represent the same disease process as CG in native kidneys and provide further evidence that collapsing glomerular changes do not define the disease entity of CG, but rather represent a pattern of renal injury. Among other factors, hemodynamic disturbance may play a role in the development of the pattern of CG in renal allografts. 相似文献
89.
90.
Carol O. Tacket Frances Hickman Gloria V. Pierce Luis F. Mendoza 《Journal of clinical microbiology》1982,16(5):991-992
We report the isolation in the United States of Vibrio fluvialis from the stools of a patient who had severe watery diarrhea without fever and who subsequently died. V. fluvialis, a known enteric pathogen in other parts of the world, should be suspected in patients with watery diarrhea, especially in coastal areas. 相似文献