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51.
Gad Elhak N Abd Elwahab M Nasif WA Abo-Elenein A Abdalla T el-Shobary M Haleem M Yaseen A el-Ghawalby N Ezzat F 《Hepato-gastroenterology》2004,51(56):485-490
BACKGROUND/AIMS: Cholecystectomy may lead to anatomic and functional alterations which eventually induce reflux of duodenal contents with its sequlae. The aim of this study is to evaluate the prevalence of Helicobacter pylori (H. pylori), gastric myoelectrical activities and gastric mucosal changes before and after laparoscopic cholecystectomy. METHODOLOGY: This prospective study has been carried out on 46 patients (20 M & 26 F) with mean age 41.7+/-0.2 years for whom laparoscopic cholecystectomy for gallstones was carried out. Prior to the operation and 1 year after, all patients were subjected to clinical assessment, upper gastrointestinal endoscopy, histopathology of antral mucosa, reflux gastritis score, detection of H. pylori and electrogastrography. RESULTS: There was an increase in the postoperative suggestive symptoms of reflux gastritis compared to the preoperative: epigastric pain increased from 8 (17.4%) to 11 (23.39%) patients, nausea increased from 6 (13%) to 12 (26.1%) and bilious vomiting increased from 3 (6.5%) to 11 (23.9%) patients. Mild antral gastritis was detected endoscopically before laparoscopic cholecystectomy in 20 patients (43.5%) and increased to 27 patients (58.7%) after surgery. Meanwhile, severe antral gastritis and erosions were only detected after the operation in 10 (21.7%) patients, respectively. The histological results showed an increase of the histopathologic score of reflux gastritis after cholecystectomy from 4.28 (+/-1.56) to 9.28 (+/-1.99) (p<0.001). Active chronic superficial gastritis decreased from 23 (50%) to 13 (28.2%) patients while the inactive form increased from 15 (32.6%) to 23 (50%) patients. Also, chronic atrophic gastritis, intestinal metaplasia and dysplasia were detected postoperatively in 4 (8.6%) patients. The incidence of H. pylori infection was decreased from 32 (69.6%) to 19 (41.3%) patients (p<0.0001). Electrogastrography abnormal frequency decreased in fasting from 26.1% to 8.7% (p<0.001), and postprandial from 16.9% to 4.4% recording (p<0.002). On the other hand, there was an increase in the number of patients with decreased electrogastrography amplitude after a meal from 4.3% to 28.3% (p<0.0001). CONCLUSIONS: Our study shows that dyspeptic symptoms, endoscopic and histologic gastric changes as well as electrogastrography abnormalities are present before and increase after cholecystectomy; meanwhile H. pylori colonization in gastric mucosa is decreased after cholecystectomy. 相似文献
52.
Disruption of the gene for the cyclin dependent kinase inhibitor (CDKI) p27/kip1 results in pituitary corticotroph hyperplasia while diminished expression of this protein has been described in aggressive human pituitary tumors. We have previously shown that 1,25-vitamin D3 (VD) hypophosphorylates p27 and interferes with the degradation of this CDKI in thyroid carcinoma cells. In this study we investigated whether VD/EB1089 can induce p27 accumulation and cause growth arrest of pituitary corticotroph cells. VD and EB1089 exhibited a significant reduction in AtT20 corticotroph but not PRL235 lactotroph cell growth. These changes were accompanied by selective accumulation of p27 in AtT20 but not in PRL235 cells. As p27 levels are highly dependent on protein degradation, we examined the effect of VD/EB1089 on p27 association with factors that target this CDKI to the proteasome. VD/EB1089 significantly restricted the association of p27 with Skp2 as well as with cyclin dependent kinase 2 (CDK2). As the tumor suppressor and phosphatase PTEN has been implicated in p27 regulation, we tested whether the effects of VD/EB1089 on p27 accumulation in corticotrophs could be mediated through this pathway. VD/EB1089 did not appreciably alter PTEN expression. Moreover, transfection of PTEN did not influence the effect of VD on p27 accumulation in corticotrophs. We conclude that VD/EB1089 can selectively arrest pituitary corticotroph growth and induce p27 accumulation.This effect is mediated at least partially through diminished p27 association with Skp2 and with CDK2. In contrast to other cell systems, PTEN does not participate in the regulation of corticotroph p27 and is not involved in mediating the effect of VD on p27 in these cells. Our findings highlight p27 and VD analogs as targets for manipulation and drug development respectively in the treatment of inoperable corticotroph adenomas. 相似文献
53.
Bazarbashi S Rahal M Raja MA El Weshi A Pai C Ezzat A Ajarim D Memon M Al Fadda M 《Chemotherapy》2002,48(4):211-216
BACKGROUND/OBJECTIVES: Based on the synergistic effect between cisplatin and 5-fluorouracil (5-FU), and between 5-FU and interferon-alpha, we conducted a trial to assess the response rate and toxicity of the combination of cisplatin, 5-FU and interferon-alpha in patients with advanced esophageal cancer. METHODS: Patients with locally advanced or metastatic squamous cell or adenocarcinoma of the esophagus were eligible. No prior chemotherapy or interferon were allowed. Patients received cisplatin 80 mg/m(2) on day 1, 5-FU 750 mg/m(2)/day by continuous intravenous infusion for 5 days, and interferon-alpha 5 x 10(6) units/m(2)/day by subcutaneous injection on days 1-5 of each cycle. Cycles were repeated every 21 days for a total of 6 cycles. RESULTS: Forty patients were enrolled. Median age was 57.5 years (range 30-70). 33 had squamous carcinoma and 7 adenocarcinoma; 15 were male; the locoregional metastatic ratio was 1:39; median ECOG performance status was 2 (range 1-3). Grade 3-4 toxicities were: leukopenia (9 cases), thrombocytopenia (4), electrolyte imbalance (11), febrile neutropenia (11), vomiting (5), diarrhea (4), and mucositis (11). There were 3 early deaths, most probably related to therapy. Five patients (13%) achieved a complete response and 17 (42%) achieved a partial response, yielding an overall response rate of 55%. Response rates for squamous and adeno histology were 61% and 29%, respectively. Median survival was 6.4 months. CONCLUSION: The combination of cisplatin, 5-FU and interferon-alpha produces a high response rate in advanced squamous cell esophageal carcinoma, but with considerable toxicity. A modified combination of the above agents is presently being evaluated at our institution. 相似文献
54.
Kehely A Bates PC Frewer P Birkett M Blum WF Mamessier P Ezzat S Ho KK Lombardi G Luger A Marek J Russell-Jones D Sönksen P Attanasio AF 《The Journal of clinical endocrinology and metabolism》2002,87(5):1974-1979
The aim of GH replacement therapy in GH-deficient adults is to optimize response with minimum incidence of adverse reactions, but optimal therapy regimens are still to be established. This two-arm parallel study examined effects of two GH dose algorithms in adults with GH deficiency of adult or childhood onset. Patients on low dose (LD; n = 302) received GH at 3 microg/kg per day for 3 months increasing to 6 microg/kg per day for 3 months, and those on conventional dose (CD; n = 293) started on 6 microg/kg per day for 3 months increasing to 12 microg/kg per day for 3 months. The proportion of patients completing therapy was greater for the LD group than the CD group for the first 3 months (93.0% vs. 88.1%; P = 0.037) and overall for the 6 months (90.7% vs. 84.0%; P = 0.013). Both dose groups showed significant increases in lean body mass and decreases in fat mass for all time points. Percent increase in lean body mass was less with LD than CD over the first 3 months (2.43 +/- 4.33 vs. 3.58 +/- 4.69%; P = 0.006) but not overall for the 6-month period (4.38% +/- 5.34% vs. 5.21% +/- 5.99%; P = 0.141). Percent decrease in fat mass was less with LD than CD for the first 3 months (-2.81% +/- 7.81% vs. -5.53% +/- 8.64%; P < 0.001) and overall for the 6-month period (-6.35% +/- 9.42% vs. -9.45% +/- 12.07%; P = 0.006). IGF-I SD score increased less with LD than CD for 0 to 3 and 0 to 6 months, although for IGF-binding protein-3 SD score, there was no significant difference between doses at any time. Arthralgia was the only adverse event that occurred significantly less frequently with LD than with CD. Calculated changes based on gender and onset indicated greater changes in males than females for body composition, but there was little difference in GH-related adverse events between males and females. The lower starting dose with dose titration appeared more favorable, but differences in response between genders and onset of GH deficiency need to be taken into account when setting an individual dose regimen. 相似文献
55.
Insulin exerts a vasodilatory effect through the release of nitric oxide (NO) from the endothelium. We have recently demonstrated that insulin also inhibits the expression of intracellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1), 2 major proinflammatory mediators, by human aortic endothelial cells (HAEC) and the proinflammatory mediator, nuclear factor (NF-kappa B), in the nucleus in parallel with an increase in endothelial nitric oxide synthase (e-NOS) expression. The inhibition of ICAM-1 by insulin is NO dependent. Because tumor necrosis factor-alpha (TNF-a ) is proinflammatory and may thus inhibit the action of insulin at the endothelial cell level, we have now investigated whether TNF-a affects (1) insulin receptor content; (2) insulin receptor (IR) autophosphorylation induced by insulin, and (3) e-NOS expression by the endothelial cells. TNF-alpha (1 to 5 ng/mL) caused e-NOS inhibition in a dose-dependent fashion as measured by Western blotting. This inhibition was reduced with insulin addition. TNF-alpha also inhibited tyrosine autophosphorylation of the IR in HAEC induced by insulin and reduced IR beta-subunit protein expression in HAEC. These effects of insulin and TNF-alpha were independent of cell proliferation, as cell counts did not change with insulin or TNF-alpha. Our data demonstrate that TNF-alpha may exert its effect by inhibiting IR autophosphorylation in HAEC and also by reducing IR protein (IRP) expression. Although the inhibition of IR autophosphorylation by TNF-alpha is known to occur at the adipocyte level, the data on the inhibitory effect of TNF-alpha on insulin-induced e-NOS expression and IRP contents are novel. 相似文献
56.
Pagura SM Thomas SG Woodhouse LJ Ezzat S 《Clinical orthopaedics and related research》2003,(415):202-213
Women experience greater functional impairment and occurrence of osteoarthritis than men. We hypothesized that lower levels of serum insulin-like growth factor-I may contribute to gender differences in physical impairments. A cross-sectional comparison (n = 139) was done on candidates having total knee arthroplasty and healthy controls subjects of similar age (range, 55-75 years). Physical function, perceived function, and serum insulin-like growth factor levels were compared across group and gender using analysis of variance. Insulin-like growth factor-I values were markedly reduced in women overall and women having surgery had significantly reduced levels despite lean body mass correction. Values consistent with clinical hormone deficiency were observed in 21% of women and only 4% of men having arthroplasty. Physical function was markedly reduced in women, at times functioning only 33% when compared with healthy women, whereas men's limitations were not as profound. The current findings indicate that physical function is more impaired and serum insulin-like growth factor-I is markedly reduced in women awaiting arthroplasty than their male counterparts. The gender differences observed biochemically and with functional performance indicate that the pathophysiology of end stage osteoarthritis may differ between men and women. 相似文献
57.
Cisplatin based combination chemotherapy remains the mainstay for treatment of advanced urothelial cancer. The combination of 5-fluorouracil and interferon has been found to be effective second line treatment of advanced urothelial cancer. Hence, we tested the combination of cisplatin, 5-fluorouracil and interferon as first line therapy in advanced urothelial cancer. Eligible patients had to have no prior chemotherapy or interferon. Treatment consisted of cisplatin 80 mg/m(2) on day one, followed by 5-fluorouracil 750 mg/m(2) as a daily infusion for 5 days and interferon alpha 2 B 5 MU/m(2) subcutaneously daily on day 1-5 of 5-fluorouracil infusion. Cycles repeated every 21 days. Eighteen patients, of which sixteen were males were enrolled. Median age was 60 years. All patients had transitional-cell carcinoma. The median number of cycles given was 4. Thirteen patients were evaluable for response. Two patients achieved CR and 3 PR for an overall response rate of 28% (95% confidence interval 7% to 49%). Median response duration was 8.3 months. Median survival was 5.5 months. Four patients died secondary to chemotherapy toxicities. Those were GI perforation in one, bronchopneumonia in one, acute renal failure in one and one patient died at home 3 weeks following the third cycle. The above regimen demonstrates excessive toxicity and moderate activity. It cannot be recommended in its present format. Novel anti-cancer agents need to explored. 相似文献
58.
Gortzak E Azzarelli A Buesa J Bramwell VH van Coevorden F van Geel AN Ezzat A Santoro A Oosterhuis JW van Glabbeke M Kirkpatrick A Verweij J;E.O.R.T.C. Soft Tissue Bone Sarcoma Group the National Cancer Institute of Canada Clinical Trials Group/Canadian Sarcoma Group 《European journal of cancer (Oxford, England : 1990)》2001,37(9):1096-1103
The aim of this study was to examine the strategy, feasibility and outcome of neo-adjuvant chemotherapy, with doxorubicin and ifosfamide, in adult patients with 'high-risk' soft-tissue sarcomas. Patients with 'high-risk' soft-tissue sarcomas, defined as tumours > or =8 cm of any grade, or grade II/III tumours <8 cm, or grade II/III locally recurrent tumours, or grade II/III tumours with inadequate surgery performed in the previous 6 weeks and therefore requiring further surgery, were randomised between either surgery alone or three cycles of 3-weekly doxorubicin 50 mg/m(2) intravenous (i.v.) bolus and ifosfamide 5 g/m(2) (24 h infusion) before surgery. The type of surgery had to be planned at randomisation. Tumours were to be amenable to surgery by amputation, compartmental resection, wide or marginal excision. If chemotherapy was given, surgery had to be performed within 21 days after the last chemotherapy. Patients received postoperative radiotherapy in cases of marginal surgery, microscopically incomplete resection and no further possibility for surgery, and in cases of surgery because of local recurrence. 150 patients were entered into the study and 134 were eligible, 67 in each arm. The most frequent side-effects of chemotherapy were alopecia, nausea and vomiting (95%), and leucocytopenia (32%). One patient died of neutropenic fever after the first cycle of chemotherapy. Chemotherapy did not interfere with planned surgery and did not affect postoperative wound healing. Limb-salvage was achieved in 88%, amputation was necessary in 12% (all according to the plan at randomisation). The trial was closed after completion of phase II, since accrual was too slow to justify expanding the study into the scheduled phase III study. At a median follow-up of 7.3 years, the 5 year disease-free survival is estimated at 52% for the no chemotherapy and 56% for the chemotherapy arm (standard error: 7%) (P=0.3548). The 5 year overall survival for both arms is 64 and 65%, respectively (standard error 7%) (P=0.2204). Neo-adjuvant-chemotherapy with doxorubicin and ifosfamide at these doses and with this schedule was feasible and did not compromise subsequent treatment, surgery with or without radiotherapy. Although not powered to draw definitive conclusions on benefit, but with an at least 7 year median follow-up, the results render it less likely that major survival benefits will be achieved with this type of chemotherapy. 相似文献
59.
The idea of immunological surveillance against cancer has existed for nearly 100 years but as no conclusive evidence has yet been published the importance of the cellular immune defense in the detection and removal of incipient or existing tumors is still a hotly debated subject. However, in order to select a relevant immunotherapeutic strategy in the treatment of cancer, a fundamental understanding of the basic immunologic conditions under which a tumor develops and exists is a prerequisite. Therefore, a murine model was set up that we hoped would enable us to confirm or reject the theory of immunological surveillance. A large panel of methylcholanthrene induced tumors was established in T-cell immunodeficient nude mice and congenic normal mice to study the influence of the immune system on developing tumors. As nude mice developed tumors fastest and with the highest incidence, we concluded that in this model the immune system constituted a 'tumor-suppressive factor' delaying and sometimes abrogating tumor growth, i.e. performing immune surveillance. Immunogenicity of the tumors was assessed by transplantation back to normal histocompatible mice. Tumors originating from the immunodeficient nude mice turned out to be far more immunogenic than tumors from normal mice, resulting in a high rejection rate. CD8+ cytotoxic T cells were found to be indispensable for this rejection, leading to the conclusion that the cytotoxic T cells perform immune selection in normal mice, eliminating immunogenic tumor cell variants in the incipient tumor. In this review, we discuss the difficulties facing immunotherapy when conclusions are drawn from the presented observations and hypotheses. 相似文献
60.
The clinical history and histological features of seven cases of granulomatous mastitis are presented. The lesion occurs in young parous women as a tender extra-areolar breast lump. Histologically, non-caseating discrete granulomas are present, confined to breast lobules with, in three cases, coalescence of the granulomas and microabscess formation. Pathogenesis of the changes is discussed. It is thought that granulomatous mastitis is an entity morphologically distinct from duct ectasia/plasma cell mastitis and the commoner forms of granulomatous breast diseases. 相似文献