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排序方式: 共有2828条查询结果,搜索用时 15 毫秒
31.
Qing-Yi Lu Yu-Sheng Jin Allan Pantuck Zuo-Feng Zhang David Heber Arie Belldegrun Mai Brooks Robert Figlin Jianyu Rao 《Clinical cancer research》2005,11(4):1675-1683
Alteration of actin polymerization and loss of actin filaments is a marker of cellular dedifferentiation and early malignant transformation. To study this phenomenon, an in vitro human urothelial model consisting of two cell lines, HUC-PC and MC-T11, were incorporated into the study design. These two cell lines have different malignant transformation potential. The effect of green tea extract (GTE), a potential anticancer agent, on actin remodeling was investigated. Upon exposure to the carcinogen 4-aminobiphenyl (4-ABP), the untransformed HUC-PC undergoes malignant transformation whereas the transformed MC-T11 progresses from noninvasive to invasive tumor. GTE induces actin polymerization in MC-T11 cells in a dose-responsive manner, but this effect is less obvious in the untransformed, more differentiated HUC-PC cells, which natively have higher actin polymerization status. In contrast, GTE antagonizes carcinogen 4-ABP induced actin depolymerization and stress fiber disruption in HUC-PC cells. In MC-T11 cells, GTE inhibits 4-ABP induced motility by increasing cell adhesion and focal adhesion complex formation. The effect of GTE on actin remodeling seems to be mediated by the stimulation of small GTP-binding protein Rho activity, because C3 exoenzyme, a specific inhibitor for Rho, blocks GTE-mediated Rho activation and stress fiber formation in MC-T11 cells. This study shows that GTE exerts an effect on cytoskeletal actin remodeling and provides further support for the use of GTE as a chemopreventive agent. 相似文献
32.
Pang-Hsien Tu Caterina Giannini Alexander R Judkins Jason M Schwalb Richard Burack Brian P O'Neill Anthony T Yachnis Peter C Burger Bernd W Scheithauer Arie Perry 《Journal of clinical oncology》2005,23(24):5718-5727
PURPOSE: Although rare overall, marginal zone B-cell lymphoma (MZBCL) is the most common primary low-grade CNS lymphoma reported in the literature. The aim of this study is to elucidate the biology and genetic features of this unusual tumor. PATIENTS AND METHODS: Fifteen CNS MZBCLs were studied clinically, pathologically, and genetically, including fluorescent in situ hybridization analyses with commercially available MALT1 and IgH break-apart and centromere 3, 7, 12, and 18 probes. RESULTS: CNS MZBCLs preferentially affect middle-aged women (female-to-male ratio, 4:1), with 93% presenting as dural-based masses mimicking meningioma. Ten patients with 1 to 7.6 years of follow-up after diagnosis showed no evidence of disease after radiation and/or chemotherapy. Like MZBCLs outside of the CNS, they consisted of CD20+, CD3- small B lymphocytes with varying degrees of plasmacytic differentiation and predominantly kappa light-chain restriction (78%). Lymphoid follicles with follicular colonization were seen in three patients and deposition of amyloid was noted in samples from two patients, one of which was tumefactive. Neither Bcl-6 protein nor Epstein-Barr virus-encoded RNA was expressed. Trisomy 3 was detected in six of 12 patients, with no rearrangements of MALT1 or IgH and no trisomies of 7, 12, or 18 detected. CONCLUSION: Our data suggest that intracranial MZBCL is an indolent primary CNS lymphoma that typically presents as a meningioma-like dural-based mass. Trisomy 3, but not MALT1 or IgH translocation, is a common genetic abnormality that may contribute to the pathogenesis of this CNS lymphoma. 相似文献
33.
Arie Erman Semyon Veksler Uzi Gafter Geoffrey Boner Clara Wittenberg David Jonathan van Dijk 《Journal of the renin-angiotensin-aldosterone system》2004,5(3):146-151
INTRODUCTION: Combination therapy with angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) is used to improve renal outcome achieved by monotherapy in diabetic patients. In addition, interference with the renin-angiotensin system (RAS) reduced expression and excretion of transforming growth factor beta 1 (TGF-beta 1) in diabetic nephropathy. The aim of this study was to investigate the effects of interrupting the RAS by ACE inhibitor (ACE-I) or ARB monotherapy or by combination therapy on proteinuria, kidney hypertrophy and plasma TGF-beta 1 in diabetic rats. MATERIALS AND METHODS: Forty-one male Wistar rats were allocated to five groups: 1 = control rats, 2 = diabetic rats (streptozotocin [STZ] 55 mg/kg), 3 = diabetic rats as above receiving enalapril (20 mg/kg/day), 4 = diabetic rats receiving losartan (80 mg/kg/day), 5 = diabetic rats receiving both losartan and enalapril. The study lasted 60 days. RESULTS: Urinary protein excretion, kidney weight, serum ACE activity and plasma TGF-beta1 increased significantly in untreated diabetic rats compared with controls. Administration of losartan, enalapril, or both for 60 days prevented these changes. Furthermore, combined therapy for 30 days normalised urinary protein excretion, while monotherapy did not. Losartan inhibited serum ACE activity both in vivo and in vitro. Plasma TGF-beta 1 levels were positively correlated with blood glucose levels (r=0.4059) and with urinary protein excretion (r=0.3558). CONCLUSIONS: Combination therapy with losartan and enalapril was more effective than monotherapy with either drug in achieving an early antiproteinuric response. Long-term treatment with losartan was as effective as the combined treatment, possibly due to a dual inhibitory effect on the RAS. The antiproteinuric effect may be related, in part, to reduced TGF-beta 1. 相似文献
34.
Kaufman Y Hirsch I Ostrovsky L Klein O Shnaider I Khoury E Pizov R Lissak A 《Journal of minimally invasive gynecology》2008,15(5):554-558
STUDY OBJECTIVE: To evaluate the efficacy of intraperitoneal nebulization of ropivacaine on pain relief during and after gynecologic laparoscopic procedures including a review of the literature. DESIGN: Double-blinded, randomized, controlled, clinical trial (Canadian Task Force classification I). SETTING: University hospital ambulatory gynecoendoscopic department. PATIENTS: Forty patients (20 patients in each arm) undergoing elective gynecologic same-day outpatient laparoscopic surgery including unilateral/bilateral salpingo-oophorectomy or unilateral/bilateral ovarian cystectomy. INTERVENTIONS: The study group received 10 mL of 1% ropivacaine and the control group received 10 mL of sterile water by intraperitoneal nebulization. During surgery, vital signs were recorded and summarized. Postoperatively patients were followed up for 24 hours including visual analog scale scores and analgesic use. MEASUREMENTS AND MAIN RESULTS: No significant differences existed between the groups during surgery and at the recovery department in terms of arterial blood pressure (p = .42) or heart rate (p = .60). Regarding postoperative analgesia, no difference existed between the groups in terms of morphine consumption (p = .52) or other analgesics (p = .53). No significant difference existed between the groups in postoperative visual analog scale scores including visceral, abdominal wall, and shoulder pain during rest and during cough at the different time frames (30, 60, and 120 minutes and 6 and 24 hours after surgery). CONCLUSION: Our study is the first to examine the effects of intraperitoneal nebulization of ropivacaine throughout laparoscopic gynecologic procedures on patients undergoing general anesthesia. Nebulization of 100 mg of ropivacaine under our specific regimen of anesthesia does not improve patients' outcome in terms of intraoperative and postoperative pain along with consumption of analgesics. Further research with other regimens is required. 相似文献
35.
Clinical, sonographic, and epidemiologic features of second- and early third-trimester spontaneous antepartum uterine rupture: a cohort study 总被引:1,自引:0,他引:1
OBJECTIVE: To present prenatal findings and maternal and neonatal outcomes following second- and early third-trimester spontaneous antepartum uterine rupture events in our institute. METHOD: Charts of patients with full-thickness second- or early third-trimester symptomatic uterine ruptures locally treated between 1984 and 2007 were evaluated. RESULTS: There were seven events involving six women, all requiring emergency laparotomy, and cesarean section (CS). During the study period in our institute, there were 120 636 singleton deliveries (> or =22 weeks' gestation), including 5 of our cases, while in 2 cases, the rupture occurred earlier (<22 weeks' gestation). The rupture occurred after > or = 1 previous CSs in five cases. Six events were associated with abnormal placentation: placenta previa (n = 3), placenta percreta (n = 1), or both (n = 2). Other associated events included short, interpregnancy (IP) interval (n = 3) and past uterine rupture (n = 2). Pregnant women at gestational age > or = 22 weeks, who had the combination of placenta previa, and previous CS (n = 3), had a higher chance for spontaneous symptomatic antepartum uterine rupture when compared to women with placenta previa without a previous CS (OR 29.3, 95% CI 1.5-569.3, p = 0.007). There were no maternal deaths. Three of the five viable neonates survived. CONCLUSIONS: Spontaneous symptomatic second- or early third-trimester uterine rupture in nonlaboring women is a very rare, obstetric emergency, which is hard to diagnose. Maternal and neonatal outcomes can be optimized by awareness of risk factors, recognition of clinical signs and symptoms, and availability of ultrasound to assist in establishing diagnosis, and enabling prompt surgical intervention. 相似文献
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40.
Matthew D. Cykowski Richard A. Allen Angela C. Kanaly Kar-Ming Fung Roxanne Marshall Arie Perry Ethan D. Stolzenberg S. Terence Dunn 《Journal of neuro-oncology》2013,115(3):477-486
Rare pilocytic astrocytomas (PA) have atypical histologic and clinicoradiologic features that raise the differential diagnosis of glioblastoma. Whether ancillary studies can supplement histopathologic examination in placing these cases accurately on the spectrum of WHO Grade I PA to higher-grade glioma is not always clear, partly because these cases are not common. Here, ten PAs with atypical clinicoradiologic and histologic features and six pediatric glioblastoma multiforme (pGBMs) were analyzed for BRAF V600E, IDH1, IDH2, and TP53 mutations. Ki-67, p53, and p16 protein expression were also examined by immunohistochemistry. BRAF–KIAA1549 fusion status was assessed in the PA subgroup. The rate of BRAF–KIAA1549 fusion was high in these PAs (5/7 tumors) including four extracerebellar examples. A single BRAF V600E mutation was identified in the fusion-negative extracerebellar PA of a very young child who succumbed to the disease. TP53 mutations were present only in malignant gliomas, including three pGBMs and one case designated as PA with anaplastic features (with consultation opinion of pGBM). IDH1 and IDH2 were wild type in all cases, consistent with earlier findings that IDH mutations are not typical in high-grade gliomas of patients ≤14 years of age. Immunohistochemical studies showed substantial overlap in Ki-67 labeling indices, an imperfect correlation between p53 labeling and TP53 mutation status, and complete p16 loss in only two pGBMs but in no PAs. These results suggest that (a) BRAF–KIAA1549 fusion may be common in PAs with atypical clinicoradiologic and histologic features, including those at extracerebellar sites, (b) BRAF V600E mutation is uncommon in extracerebellar PAs, and (c) TP53 mutation analysis remains a valuable tool in identifying childhood gliomas that will likely behave in a malignant fashion. 相似文献