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991.
Complete remission in severe aplastic anemia after high-dose cyclophosphamide without bone marrow transplantation 总被引:6,自引:1,他引:6
Severe aplastic anemia (SAA) can be successfully treated with allogeneic bone marrow transplantation (BMT) or immunosuppressive therapy. However, the majority of patients with SAA are not eligible for BMT because they lack an HLA-identical sibling. Conventional immunosuppressive therapy also has major limitations; many of its remissions are incomplete and relapse or secondary clonal disease is common. Cyclophosphamide is a potent immunosuppressive agent that is used in all BMT conditioning regimens for patients with SAA. Preliminary evidence suggested that high-dose cyclophosphamide, even without BMT, may be beneficial to patients with SAA. Therefore, 10 patients with SAA and lacking an HLA-identical sibling were treated with high-dose cyclophosphamide (45 mg/kg/d) for 4 consecutive days with or without cyclosporine. A complete response (hemoglobin level, > 13 g/dL; absolute neutrophil count, > 1.5 x 10(9)/L, and platelet count > 125 x 10(9)/L) was achieved in 7 of the 10 patients. One of the complete responders died from the acquired immunodeficiency syndrome 44 months after treatment with high-dose cyclophosphamide. The 6 remaining patients are alive and in continuous complete remission, with a median follow-up of 10.8 years (range, 7.3 to 17.8 years). The median time to last platelet transfusion and time to 0.5 x 10(9) neutrophils/L were 85 and 95 days, respectively. None of the complete responders has relapsed or developed a clonal disease. These results suggest that high-dose cyclophosphamide, even without BMT, may be more effective than conventional immunosuppressive therapy in restoring normal hematopoiesis and preventing relapse or secondary clonal disorders. Hence, further studies confirming the efficacy of this approach in SAA are indicated. 相似文献
992.
Lovastatin inhibits T-cell antigen receptor signaling independent of its effects on ras 总被引:1,自引:0,他引:1
Lovastatin, a cholesterol-lowering drug, has antiproliferative properties that may be related to its inhibition of protein isoprenylation. We examined the effects of lovastatin on signal transduction via the T-cell antigen receptor (TCR). Lovastatin inhibited both proximal and distal TCR-mediated signaling events in a time- and concentration-dependent manner in the human Jurkat T-cell line. Upregulation of CD69 surface expression after TCR stimulation was blocked by lovastatin, although no inhibition of phorbol ester-induced CD69 expression was noted. Proximal TCR-mediated signaling events, including intracellular calcium mobilization, inositol phosphate production, and tyrosine phosphorylation of phospholipase Cgamma1, were similarly inhibited by lovastatin, although global protein tyrosine kinase activity remained intact. In a Jurkat variant transfected with the human type-1 muscarinic receptor, lovastatin also inhibited TCR- mediated calcium mobilization and inositol phosphate production but failed to affect muscarinic receptor-induced responses. Lovastatin, at similar doses, also disrupted post-translational processing of ras and inhibited ras-dependent signals, including phosphorylation and activation of mitogen-associated protein kinase after TCR stimulation. These findings suggest that the antiproliferative properties of lovastatin may be independent of ras and could result from uncoupling protein tyrosine kinases from distinct signal transduction pathways. 相似文献
993.
Bordignon C; Keever CA; Small TN; Flomenberg N; Dupont B; O'Reilly RJ; Kernan NA 《Blood》1989,74(6):2237-2243
To identify mechanisms potentially contributing to graft failure, 19 leukemic recipients of T-cell-depleted marrow transplants who failed to engraft following a transplant of HLA identical sibling marrow depleted of T cells by soybean agglutinin (SBA) and sheep erythrocytes (E) were evaluated. Peripheral blood mononuclear cells isolated at the time of failure were consistently of host origin, bearing the phenotype of suppressor T cells (CD3+, CD8+, Leu 7+). A direct cytolytic effect on 51Cr-labeled donor-derived target cells was not detected, a finding that contrasts with the donor-specific cytotoxic host T lymphocytes that have been regularly observed in patients rejecting HLA nonidentical SBA -E- BMTs. However, these host T cells did exhibit a strong and specific suppressive activity against the donor marrow CFU- GM in vitro. Furthermore, in contrast to prior findings in durably engrafted recipients of SBA -E- BMTs, the lymphocytes isolated prior to or at the time of graft failure lacked natural killer surface antigen expression and effector function. 相似文献
994.
Gonen Yael; Dirnfeld Martha; Goldman Shlomit; Koifman Mara; Abramovici Haim 《Human reproduction (Oxford, England)》1993,8(9):1376-1379
The present study was undertaken to assess whether the increasein serum progesterone concentration following the administrationof human chorionic gonadotrophin (HCG) may have predictive valueon the in-vitro fertilization (IVF) success rate. Progesteroneconcentration on the day of HCG administration and the increasein progesterone concentration on the following day were evaluatedin 140 consecutive patients undergoing IVF with embryo transfer.Stimulation protocol in all study patients entailed intranasaladministration of short-acting gonadotrophin-releasing hormoneagonist (GnRHa) buserelin and human menopausal gonadotrophin.A pregnancy rate of 37.2% was achieved when at least three embryoswere transferred. The only significant difference between conceptionand non-conception cycles was found in serum progesterone concentrationsafter HCG administration (P < 0.01), whereas the mean progesteroneconcentration on the day of HCG did not differ. No differencein other hormonal or cycle parameters was observed. The increasein progesterone concentration was significantly greater in thegroup of patients who achieved pregnancy than in the group whodid not (2.2 ± 0.2 versus 1.6 ± 0.1 ng/ml, respectively;P < 0.01). A critical breakpoint in serum progesterone wasarbitrarily determined at 1 ng/ml. An increase in progesteroneconcentration 1 ng/ml when three or more embryos were transferredwas associated with a positive predictive value for pregnancyof 40.4% (sensitivity of 94.7%), whereas a negative predictivevalue of 86.7% was obtained when this value was <1 ng/ml.These findings indicate that an adequate rise in serum progesteronefollowing HCG administration provides useful information aboutthe possible outcome of the treated cycle. 相似文献
995.
R A Pereira S Koifman 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2001,17(6):1313-1334
This paper reviews the scientific literature published from 1986 to 1999 assessing the relationship between dietary factors and brain tumors in adults. The work aimed to describe the estimated associations and to discuss methodological aspects that might influence the results. The studies generally appear to show a moderate association between dietary factors and brain tumors. There is evidence that N-nitroso compounds enhance the risk of developing such tumors and that consumption of fruits and vegetables can inhibit them. Use of proxies in most of the studies may have introduced bias, thereby contributing to some inconsistent observations. Epidemiological research on diet and brain tumors should consider other components of food besides N-nitroso compounds. It is important to carefully assess exposure periods and to prevent bias related to control selection and recall. 相似文献
996.
J Ashcroft AA Singh S Rooney J Bennett RJ Davies 《Annals of the Royal College of Surgeons of England》2021,103(3):203
IntroductionPatients with suspected appendicitis remain a diagnostic challenge. The aim of this study was to validate risk prediction models, and to investigate diagnostic accuracy of ultrasonography and computed tomography (CT) in adults undergoing appendicectomy.MethodsA retrospective case review was performed of patients aged 16–45 years having an appendicectomy between January 2019 and January 2020 at a tertiary referral centre. Primary outcomes were the accuracy of a high risk appendicitis risk score and ultrasonography and CT imaging modalities compared with histological reports following appendicectomy.ResultsA total of 206 patients (52% female) were included in the study. Removal of a histologically normal appendix was equally likely in men and women (13.1% vs 11.2% respectively, relative risk: 1.17, 95% confidence interval: 0.56–2.44, p=0.674). A high risk appendicitis score correctly identified 84.0% (79/94) of cases in men and 85.9% (67/78) of cases in women. Ultrasonography was reported as equivocal in 85.7% (18/21) of low risk women and 59.0% (23/39) of high risk women. CT correctly detected or excluded appendicitis in 75.0% (6/8) of low risk women and 88.5% (23/26) of high risk women.ConclusionsThis study suggests that risk prediction models may be useful in both women and men to identify appendicitis. Ultrasonography gave high rates of equivocal results and should not be relied on for the diagnosis of appendicitis. CT is a highly accurate diagnostic tool and could be considered in those at low risk where clinical suspicion remains to reduce negative appendicectomy rates. 相似文献
997.
PS Teirstein V Massullo S Jani RJ Russo DA Cloutier RA Schatz EM Guarneri S Steuterman K Sirkin S Norman P Tripuraneni 《Circulation》1999,99(2):243-247
BACKGROUND: Although early trials indicate the treatment of restenosis with radiation therapy is safe and effective, the long-term impact of this new technology has been questioned. The possibility of late untoward consequences, such as aneurysm formation, perforation, and accelerated vascular disease, is of significant concern. Furthermore, it is not known whether the beneficial effects of radiation therapy will be durable or whether radiation will only delay restenosis. METHODS AND RESULTS: A double-blind, randomized trial was undertaken to compare 192Ir with placebo sources in patients with previous restenosis after coronary angioplasty. Patients were randomly assigned to receive a 0.76-mm (0. 03-in) ribbon containing sealed sources of either 192Ir or placebo. All patients underwent repeat coronary angiography at 6 months. All living patients were contacted 24 months after their index study procedure. Patients were assessed with respect to the need for target-lesion revascularization or nontarget-lesion revascularization, occurrence of myocardial infarction, or death. Over a 9-month period, 55 patients were enrolled; 26 were randomized to 192Ir and 29 to placebo. Follow-up was obtained in 100% of living patients at a minimum of 24 months. Target-lesion revascularization was significantly lower in the 192Ir group (15.4% versus 44.8%; P<0. 01). Nontarget-lesion revascularization was similar in 192Ir and placebo patients (19.2% versus 20.7%; P=NS). There were 2 deaths in each group. The composite end point of death, myocardial infarction, or target-lesion revascularization was significantly lower in 192Ir-treated versus placebo-treated patients (23.1% versus 51.7%; P=0.03). No patient in the 192Ir group sustained a target-lesion revascularization later than 10 months. CONCLUSIONS: At 2-year clinical follow-up, treatment with 192Ir demonstrates significant clinical benefit. Although further follow-up (including late angiography) will be necessary, no clinical events have occurred to date in the 192Ir group to suggest major untoward effects of vascular radiotherapy. At the intermediate follow-up time point, vascular radiotherapy continues to be a promising new treatment for restenosis. 相似文献
998.
L Convie RJ Thompson R Kennedy WDB Clements PD Carey JA Kennedy 《Annals of the Royal College of Surgeons of England》2015,97(2):146-150
Introduction
Oesophagogastric cancers are known to spread rapidly to locoregional lymph nodes and by transcoelomic spread to the peritoneal cavity. Staging laparoscopy combined with peritoneal cytology can detect advanced disease that may not be apparent on other staging investigations. The aim of this study was to determine the current value of staging laparoscopy and peritoneal cytology in light of the ubiquitous use of computed tomography in all oesophagogastric cancers and the addition of positron emission tomography in oesophageal cancer.Methods
All patients undergoing staging laparoscopy for distal oesophageal or gastric cancer between March 2007 and August 2013 were identified from a prospectively maintained database. Demographic details, preoperative staging, staging laparoscopy findings, cytology and histopathology results were analysed.Results
A total of 317 patients were identified: 159 (50.1%) had gastric adenocarcinoma, 136 (43.0%) oesophageal adenocarcinoma and 22 (6.9%) oesophageal squamous carcinoma. Staging laparoscopy revealed macroscopic metastases in 36 patients (22.6%) with gastric adenocarcinoma and 16 patients (11.8%) with oesophageal adenocarcinoma. Positive peritoneal cytology in the absence of macroscopic peritoneal metastases was identified in a further five patients with gastric adenocarcinoma and six patients with oesophageal adenocarcinoma. There was no significant difference in survival between patients with macroscopic peritoneal disease and those with positive peritoneal cytology (p=0.219).Conclusions
Staging laparoscopy and peritoneal cytology should be performed routinely in the staging of distal oesophageal and gastric cancers where other investigations indicate resectability. Currently, in our opinion, patients with positive peritoneal cytology should not be treated with curative intent. 相似文献999.
1000.