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71.
Desmoplastic small round cell tumor (DSRCT) is a primitive sarcoma characterized by a recurrent chromosomal translocation, t(11;22)(p13;q12), which fuses the 5' exons of the EWS gene to the 3' exons of the WT1 gene. EWS-WT1 chimeras are heterogeneous as a result of fusions of different regions of the EWS gene to the WT1 gene. We report here a rare and novel EWS-WT1 variant, EWS-WT1 5/10, in a 6-year-old boy diagnosed with DSRCT and analyze the potential transactivation effect of the fusion oncoprotein. The predicted product is comprised of the N-terminal transactivation domain of EWS and lacks any sequence derived from the WT1 gene product. Nonetheless, the truncated protein was able to stimulate expression of the insulin-like growth factor-I receptor gene, a potent antiapoptotic receptor tyrosine kinase with potentially important roles in DSRCT etiology. These findings raise the possibility that the oncogenic potential of EWS-WT1 fusions is not necessarily a consequence of the fusion protein product per se.  相似文献   
72.
Infliximab is an anti-tumor necrosis factor (TNF) used for treatment of inflammatory bowel disease (IBD) as well as rheumatoid arthritis, psoriasis, and other inflammatory conditions. Antibodies to infliximab (ATI) develop in approximately 45% of infliximab-treated IBD patients and are correlated with loss of clinical response. Scarce data exist as to factors which predict infliximab immunogenicity.To investigate factors that may predict formation of antibodies to infliximab (ATI) and infliximab therapy failure an observational study of consecutive IBD patients treated with infliximab between 2009 and 2013 was performed. Trough levels of ATI were measured. Patients were monitored for disease activity using clinical activity indexes and were classified according to ATI formation and clinical response. All clinical and demographic parameters were analyzed for association with the designated outcomes.One hundred fifty-nine patients were included and 1505 sera were tested. On multivariate analysis, Jewish Ashkenazi ethnicity was protective against both development of ATI (odds ratio [OR] 0.35, 95% confidence interval [CI] 0.17–0.7, P = 0.005) and treatment failure (OR 0.29, 95% CI 0.13–0.66, P = 0.003). Concomitant immunomodulator therapy was also negatively associated with immunogenicity and infliximab therapy failure (OR 0.31, 95% CI 0.15–0.65, P = 0.002; OR 0.42 95% CI 0.18−0.99, p = 0.04, respectively), whereas episodic therapy was positively associated with both outcomes (OR 4.2 95% CI 1.07−16.1, p = 0.04, OR 4.45 95% CI 1.2−16.6, p = 0.026 respectively). All other variables, including IBD type, gender, weight, age, smoking status and disease duration, were not predictive of ATI formation or clinical failure. However, among Crohn''s disease patients, a non-stricturing non-penetrating phenotype was protective against ATI formation (OR 0.4, 95% CI 0.14−0.96, p = 0.04). P = 0.04, respectively), whereas episodic/interrupted therapy was positively associated with both outcomes (OR 4.2, 95% CI 1.07–16.1, P = 0.04; OR 4.45, 95% CI 1.2–16.6, P = 0.026, respectively). All other variables, including IBD type, sex, weight, age, smoking status, and disease duration, were not predictive of ATI formation or clinical failure. However, among Crohn disease patients, a nonstricturing nonpenetrating phenotype was protective against ATI formation (OR 0.4, 95% CI 0.14–0.96, P = 0.04).Jewish Ashkenazi ethnicity is protective of ATI formation and infliximab therapy failure. These findings suggest a role for ethnicity, and implicitly for genetic predisposition, in modulating the risk of anti-TNF immunogenicity and treatment unresponsiveness.  相似文献   
73.
The three anterior temporobasal (aTB) sulci, which are the collateral, rhinal, and occipitotemporal sulci, contribute to the morphology of memory-related structures and are important landmarks for neuroimaging. Prevalence of inter-connections among these sulci may distinguish healthy adults and individuals with memory-related disorders (Kim et al. Neurology 70:2159–2165, 2008; Zhan et al. Hum Brain Mapp 30:874–882, 2009). However, methods for quantifying the existence and nature of such connections are vague and varied, and normative frequencies are inconsistent across studies. Therefore, the goals of the current study are twofold: (1) to develop a reliable method of identifying aTB sulci and their interconnections based on surface renderings generated from serial magnetic resonance images (MRIs). This protocol includes training materials and a rating log (see supplementary materials) that can be disseminated and applied by other researchers. (2) To determine the prevalence of interconnections among the three aTB sulci in a large sample of healthy adults (200 undergraduate students), which can be used as normative data for future comparison with clinical samples. Notably, the resulting protocol, called the Sulcal Classification Rating Protocol for anterior Temporobasal sulci, distinguishes “clear” from “ambiguous” connections. When only clear connections are included, our prevalence rates are consistent with post-mortem findings of Ono et al. (Atlas of the Cerebral Sulci. Thieme Medical Publishers, Inc., New York, 1990); when both clear and ambiguous connections are counted as a connection, our results largely replicate MRI-based findings (e.g., Kim et al. Neurology 70:2159–2165, 2008). We propose that systematic variations in rater classification of ambiguous connections could explain discrepancies in the literature.  相似文献   
74.

The purpose of the current study was to examine differences by sex (a) in history of child abuse and neglect (CAN) and exposure to parental partner violence (PPV); and (b) in the association of CAN and PPV with violent offenses, substance use, suicidal behavior, and psychiatric problems. This cross-sectional study investigated sex differences in CAN and exposure to PPV in a sample of 290 Israeli inmates (65 women and 225 men). Participants completed a self-report measures of the Childhood Trauma Questionnaire, and the revised Conflict Tactics Scale to measure PPV. The findings indicated that the female inmates had experienced significantly more sexual abuse (p?<?.001), and more exposure to PPV (p?=?.030), compared with male inmates. Female inmates who had experienced CAN were at higher risk of committing violent offenses than male inmates and female inmates were also more likely than male inmates to have been engaged in suicidal behaviors (39.3% and 18.5%, respectively), and to have had psychiatric problems (40% and 14.2%, respectively). The findings also revealed that psychiatric problems and suicidal behavior can be predicted by CAN and family substance use. The findings highlight the effects of the adverse childhood experience of exposure to CAN and PPV on behavioral problems. Appropriate treatment requires simultaneous intervention that targets all three issues of childhood trauma, substance use disorders, and psychiatric problems for both sexes.

  相似文献   
75.
Stomach conservation in stages IE and IIE gastric non-Hodgkin's lymphoma.   总被引:6,自引:0,他引:6  
Thirty-four patients with stages IE and IIE gastric lymphoma were treated with chemotherapy and radiotherapy combinations without stomach resection. In 20 patients, the diagnosis was established by endoscopic biopsy only; the other 14 had laparotomy and biopsy. No patient had a gastrectomy before treatment. Nineteen patients had stage IE disease and 15 had stage IIE. Lymphoma diagnoses were: diffuse large-cell, 26; immunoblastic, three; diffuse well-differentiated, three; nodular mixed, one; and unclassified, one. The treatment plan was to deliver an initial four cycles of chemotherapy, followed by radiotherapy, and finally, more chemotherapy. Thirty-three patients received cyclophosphamide, doxorubicin, vincristine, prednisone, and bleomycin (CHOP-Bleo). Four patients with stage IIE disease received cyclophosphamide, methotrexate, etoposide, and dexamethasone (CMED). Twenty-three patients (68%) never had a relapse. Three patients had successful salvage therapy, one for local recurrence and two for tumor dissemination. Five patients died of recurrent abdominal disease, and one died of tumor dissemination. Two died of treatment-related complications, one of sepsis during treatment with CMED and one of bleomycin-induced lung fibrosis. No patient developed stomach perforation or bleeding as a result of chemotherapy or radiotherapy. Twenty-four of the 26 surviving patients were able to retain their stomachs. One patient required a gastrectomy for progressive disease during chemotherapy, and another required a subtotal gastrectomy for relief of an obstruction caused by cicatrization. These data show that surgery is not a necessary procedure in gastric lymphoma. Favorable results can be achieved by combining effective chemotherapy and local radiation.  相似文献   
76.
BACKGROUND/AIMS: Activated hepatic stellate cells (HSCs) have been implicated in hepatic fibrosis. Somatostatin (SOM) has an immunomodulatory role. The aim of this study was to assess the secretion of pro-inflammatory cytokines by HSCs and to determine the effect of SOM on the secretion of these mediators. METHODS: Activated rat HSCs were evaluated for their secretion of IL-1beta, IL-8, and TNF-alpha using ELISA. RNA protection assay was used to determine cytokine mRNA levels. The expression of chemokine and cytokine mRNA and the secretion of these mediators were assessed following incubation with SOM or octreotide. RESULTS: HSCs spontaneously secreted IL-1beta, IL-8, and TNF-alpha. This secretion was augmented following stimulation by IL-1beta and TNF-alpha. SOM inhibited the spontaneous and TNF-alpha-induced secretion of IL-1beta, IL-8, and TNF-alpha and suppressed the expression of IL-1beta and TNF-alpha mRNA. Octreotide suppressed the secretion of IL-1beta and IL-8. CONCLUSIONS: These observations indicate that SOM exerts an inhibitory immunomodulatory effect on HSCs.  相似文献   
77.
Five hundred and fifty patients were entered into a set of dose-searching studies designed to determine normal tissue tolerance to high energy (42-66 MeV reactions) fast neutrons delivered in 12 equal fractions over 4 weeks. Participating institutions included: The Fermilab (66 MeV p+----Be), The University of Washington (50 MeVp+----Be), U.C.L.A. (45 MeVH-----Be), M.D. Anderson Hospital (42 MeVH-----Be), and The Cleveland Clinic (42 MeVp+----Be). Patients were stratified by treatment facility and then randomized to receive 16, 18 or 20 Gy for tumors located in the upper abdomen or pelvis, and 18, 20 or 22 Gy for tumors located in the head and neck, thorax or extremities. Following completion of the randomized protocols, additional patients were studied at the 20.4 Gy level in the head and neck, thorax and pelvis. Normal tissue effect scoring was accomplished using the RTOG-EORTC acute and late normal tissue effect scales. Acute Grade 3 + toxicity rates in the head and neck were 19% for 20/20.4 Gy and 20% for 22 Gy. Time adjusted late toxicity rates in the head and neck at 12 months were 15% for 20/20.4 Gy and 0% for 22 Gy. The 18 Gy treatment arm of the head and neck protocol was dropped early in the study after only two patients were accrued. For cases treated in the thorax, acute Grade 3 + toxicity rates were 6% for 18 Gy, 15% for 20/20.4 Gy and 7% for 22 Gy. Late toxicity rates at 12 months were 0% for 18 Gy, 11% for 20/20.4 Gy and 18% for 22 Gy. Acute Grade 3+ toxicity rates in the upper abdomen were 0% for 16 Gy, 8% for 18 Gy and 12% for 20 Gy. There were no Grade 3 + late toxicities in the upper abdomen. In the pelvis, acute Grade 3 + toxicity rates were 0% for 16 Gy, 3% for 18 Gy and 3% for 20/20.4 Gy. Late Grade 3 + toxicities at 24 months were 20% for 16 Gy, 5% for 18 Gy and 24% for 20/20.4 Gy. In extremities, acute Grade 3 + toxicity rates were 7% for 20 Gy and 21% for 22 Gy while at 12 months, late Grade 3 + toxicity rates were 14 and 35%, respectively. The 18 Gy treatment arm of the extremities protocol was dropped early in the study after only two patients were accrued. Factors associated with normal tissue effects in addition to treatment dose are discussed.  相似文献   
78.
79.
Infections with S. aureus with heterogeneous intermediate resistance to vancomycin (hVISA) are occurring more frequently. The detection of these infections, their prevalence, clinical characteristics, and significance are controversial. During 2003 and 2004, all blood culture isolates of methicillin-resistant Staphylococcus aureus (264 patients) at the Sheba Medical Center, Tel Hashomer, Israel, were assessed for hVISA by using the Etest macromethod. A total of 16 patients (6%) were positive for hVISA. Resistance to teicoplanin alone and to vancomycin alone using the Etest macromethod was found in 14 and 10 patients, respectively. Standard MICs to vancomycin were between 1 to 4 mg/ml. Most of these isolates (12 of 16 [75%]) would have been missed without specific testing. The median number of bacteremic days was 4. Seven patients had positive blood cultures for more than 5 days. Twelve patients died, and for eight of these the deaths were directly related to hVISA sepsis. We found that hVISA bacteremia was prevalent in our institution, and we suggest seeking hVISA in patients with persistent S. aureus bacteremia.  相似文献   
80.
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