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31.
Histiocytic sarcoma (HS) is a rare malignant proliferation of histiocytes of uncertain molecular pathogenesis. Here, genetic analysis of coincident loss of Pten and Ink4a/Arf tumor suppressors in the mouse revealed a neoplastic phenotype dominated by a premalignant expansion of biphenotypic myelolymphoid cells followed by the development of HS. Pten protein loss occurred only in the histiocytic portion of tumors, suggesting a stepwise genetic inactivation in the generation of HS. Similarly, human HS showed genetic or epigenetic inactivation of PTEN, p16(INK4A), and p14(ARF), supporting the relevance of this genetically engineered mouse model of HS. These genetic and translational observations establish a cooperative role of Pten and Ink4a/Arf in the development of HS and provide mechanistic insights into the pathogenesis of human HS.  相似文献   
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Most of the cocaine - deaths are said to be related to cardiovascular complications. This paper addresses a rather infrequent complication of chronic cocaine use, represented by the aortic dissection. The case in point pertains to a 45-year-old, caucasian male, substance abuser who suffered an aortic dissection following the use of cocaine. Blood concentrations of cocaine and benzoylecgonine were considered not to be within a potentially toxic range.  相似文献   
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A 35-year-old woman presented with dyspnea, recurrent laryngitis and gastroesophageal reflux disease. Laryngoscopic examination revealed a yellow lesion on the anterior site of the left true vocal cord. No abnormal lesions were found in other portions of the larynx. The lesion was biopsied and a histological examination showed numerous foamy cells diffusely presented in the stroma of the specimen. Overlying squamous epithelium did not show cellular atypia. On the basis of histological appearance, the possible differential diagnosis included xanthomatous lesion, granular cell tumor or epithelial neoplasia. CD68, S-100 protein and cytokeratin immunoreactivities were investigated. Immuno-histochemically, foamy cells were positive for CD68, indicating a histiocytic origin.  相似文献   
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Despite being treated with antiresorptive drugs, the severe osteoporosis (SO) is being considered as a condition in which patients are still subject to one or more vertebral or femoral fractures, or non-vertebral or non-femoral fractures, i.e., of other parts of the body such as the wrist, shoulder, tibia, ribs or hip. These patients are defined as non-responders (NRs) to the antiresorptive therapy, and recent research has shown that they represent 10-25% of all SO patients. During the last almost 3 years a new drug has become available in Italy, called teriparatide (rh-PTH-1-34), produced in Escherichia coli using the recombinant-DNA technique. It shows remarkable trophic and anabolic actions on the bones, and proved to be very useful for treating the osteoporosis in general. This study describes our experience in using teriparatide for the treatment of SO in a sample of 141 elderly women of mean age 73.4+/-5.8 years, with a mean number of fractures of 3.0+/-0.85, with a spine deformity index (SDI) of 5.92+/-1.27 and a mean vertebral T-Score (L1-L4) of -3.15+/-0.39, and a mean femoral T-Score of -2.50+/-0.28. All these patients had been treated with antiresorptive drugs for at least 1 year: specifically 70 of them with Alendronate, 42 of them with Risedronate and 29 of them with Raloxifene. For 18 months, all these patients were injected subcutaneously with 20 microg of teriparatide, with the daily addition of 1 g of calcium and 880 IU of vitamin D. The study was continued for 24 months, at the end of which the patients continued to take only calcium and vitamin D. The patients underwent a CBM-DEXA control of vertebral column and femur every 6 months, and they were also administered a Quality-of-Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO). The QUALEFFO (41 items) questionnaire to evaluate the changes in the quality-of-life (QoL) and the consumption of non-steroidal anti-inflammatory drugs (NSAIDs) was also recorded. The results showed that teriparatide protected 96.5% against new fractures (only five new fractures occurred), bone mineral density (BMD) increased approximately by 12% in the vertebral column and by 11% in the femur, consumption of NSAIDs was reduced at the early stage approximately 80%, the QoL improved considerably and remained so during the 18 months of teriparatide treatment, with only a slight decrease during the 6 subsequent months.  相似文献   
35.
BACKGROUND: Chronic inflammatory diseases are associated with bone loss and an enhanced fracture risk. It is unknown, however, whether low-grade inflammation in healthy individuals, as estimated by the high-sensitivity C-reactive protein (hs-CRP) level, interferes with bone metabolism and affects the risk of nontraumatic fractures. METHODS: Lifetime bone fractures were carefully recorded in the cohort of the population-based Bruneck Study (n = 919) along with information on the date of occurrence and associated circumstances. The serum level of hs-CRP was measured from blood samples collected during the 1990 baseline examination and the 1995, 2000, and 2005 follow-up examinations. In addition, lifestyle and demographic characteristics, bone ultrasonographic data at the heel, and variables of bone metabolism were assessed. RESULTS: Between September 1, 1990, and August 31, 2005, 69 subjects experienced nontraumatic hip or vertebral fractures. The incidence of nontraumatic fractures was 1.3, 3.8, and 13.9 per 1000 person-years in the tertile groups for hs-CRP. In multivariate pooled logistic regression analysis, the adjusted relative risk (95% confidence interval) of nontraumatic fracture in the highest vs lowest tertile group for hs-CRP was 9.4 (3.6-24.8) (P < .001). The exclusion of subjects with cardiovascular disease, dementia, malignancies, and chronic inflammatory disease had little effect on the results obtained. The hs-CRP level was unrelated to ultrasonographic measures of bone density, but showed an inverse relation to laboratory markers of bone turnover, like beta-crosslaps and osteocalcin concentration (P < .001). CONCLUSIONS: The hs-CRP level is a significant and independent risk predictor of nontraumatic fracture. This finding is consistent with the hypothesis of a tight interplay between low-grade inflammation and bone turnover.  相似文献   
36.
Glioblastoma remains one of the deadliest of human cancers, with most patients succumbing to the disease within two years of diagnosis. The available data suggest that simultaneous inactivation of critical nodes within the glioblastoma molecular circuitry will be required for meaningful clinical efficacy. We conducted parallel genome-wide shRNA screens to identify such nodes and uncovered a number of G-Protein Coupled Receptor (GPCR) neurotransmitter pathways, including the Dopamine Receptor D2 (DRD2) signaling pathway. Supporting the importance of DRD2 in glioblastoma, DRD2 mRNA and protein expression were elevated in clinical glioblastoma specimens relative to matched non-neoplastic cerebrum. Treatment with independent si-/shRNAs against DRD2 or with DRD2 antagonists suppressed the growth of patient-derived glioblastoma lines both in vitro and in vivo. Importantly, glioblastoma lines derived from independent genetically engineered mouse models (GEMMs) were more sensitive to haloperidol, an FDA approved DRD2 antagonist, than the premalignant astrocyte lines by approximately an order of magnitude. The pro-proliferative effect of DRD2 was, in part, mediated through a GNAI2/Rap1/Ras/ERK signaling axis. Combined inhibition of DRD2 and Epidermal Growth Factor Receptor (EGFR) led to synergistic tumoricidal activity as well as ERK suppression in independent in vivo and in vitro glioblastoma models. Our results suggest combined EGFR and DRD2 inhibition as a promising strategy for glioblastoma treatment.  相似文献   
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The aim of this study was to analyze maternal mortality in Brazil in the last 30 years, by means of a literature review. The authors performed an electronic search of scientific articles from 1980 to 2010 in LILACS and MEDLINE and found 486 abstracts, of which 50 articles were selected. Studies showed a decrease in the maternal mortality ratio (MMR), although varying across regions of the country. A few articles evaluated maternal mortality factors, identifying social inequalities associated with skin color and schooling. There was persistent underreporting of maternal deaths and inadequate completion of death certificates. Direct obstetric causes were the most frequent, mainly hypertensive diseases of pregnancy. Analysis of avoidability revealed deficiencies in prenatal and childbirth care. Despite the relevance of maternal mortality in Brazil, there are few studies on the subject. Although MMR has decreased, it is still above the desired levels. Improvements are thus needed in the quality of prenatal and perinatal care.  相似文献   
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