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991.
目的:采用荷瘤动物模型经化疗联合被动免疫治疗,初步探讨化疗免疫"窗口期"对卵巢癌免疫应答的影响及其可能的免疫学机制。方法:以荷瘤大鼠为研究对象,根据紫杉醇联合卡铂对荷瘤鼠免疫功能改变的不同时期给予CTL(cytotoxic T-lymphocyte)主动免疫治疗。观察荷瘤体积及机体免疫微环境改变。结果:荷瘤鼠紫杉醇和卡铂化疗后不同时期给予CTL转输治疗,其中化疗后第6天即淋巴细胞数最少期,给予免疫治疗,肿瘤生长最缓慢;CT扫描结果示,化疗后6天+免疫治疗组的瘤体积最小,且与其余治疗组有统计学意义。荷瘤鼠免疫功能示,化疗后6天+免疫治疗组中淋巴细胞抗原特异性增殖及CD8+T细胞最明显,而Treg(T-Lymphocytes,Regulatory)细胞明显降低。结论:紫杉醇和卡铂联合CTL治疗肿瘤具有协同作用,其中化疗后6天(即淋巴细胞降到最低期)是CTL免疫治疗的最佳时间点。化疗造成的肿瘤个体免疫功能的低下或是免疫系统空间的释放(所谓的免疫"窗口期")为诱导特异性的抗肿瘤免疫应答提供了可能,免疫状态的检测是保证肿瘤患者化疗联合免疫治疗方案治疗有效性的重要前提之一。 相似文献
992.
Aimaretti G Corneli G Di Somma C Baldelli R Gasco V Rovere S Migliaretti G Colao A Tamburrano G Lombardi G Ghigo E Camanni F 《Journal of endocrinological investigation》2005,28(3):247-252
To verify if the entity of the peak GH responses to the GHRH+arginine (ARG) test is able to show different degree forms of GH deficiency (GHD), we linked these responses with the number of other anterior pituitary deficits. These anterior pituitary deficits were also related with IGF-I levels. To this purpose, we studied a large cohort of lean patients with pituitary disease of different etiologies [86 males and 68 females; age: mean +/- SEM 41.5 +/- 1.2 yr, body mass index (BMI) <25 kg/m2]. The patients were subdivided into 4 groups according to the increasing number of hormone deficiencies: isolated GHD (HYPO1, no.=28) or GHD plus one, two or three additional hormones (gonadotrophin, ACTH, and TSH) deficiencies (HYPO2, no.=20; HYPO3, no.=15; HYPO4, no.=91). Peak GH responses to the GHRH+ARG test and IGF-I levels showed a clear difference among the groups (p < 0.01 and p < 0.001, respectively). A significant difference was found between HYPO1 and HYPO4 for IGF-I levels (p < 0.05), and between HYPO1 and HYPO4 and between HYPO2 and HYPO4 for the GHRH+ARG test (p < 0.005). Considering only the patients who underwent both GHRH+ARG test and insulin tolerance test (ITT) (no.=70), the pattern of the peak GH responses to the GHRH+ARG test was the same of the whole group of patients, while no statistical difference was found with ITT. Our data show that the peak GH responses to the GHRH+ARG test and the IGF-I levels are linked to the severity of hypopituitarism, expressed by the number of increasing anterior pituitary deficits. This association is lost if the evaluation of the GH status is performed by the ITT. In all, the GHRH+ARG test and measurement of IGF-I are able to evidence different degrees of GHD in adult patients with pituitary disease. 相似文献
993.
Zamboni M Zoico E Fantin F Panourgia MP Di Francesco V Tosoni P Solerte B Vettor R Bosello O 《The journals of gerontology. Series A, Biological sciences and medical sciences》2004,59(4):396-400
BACKGROUND: Leptin has been shown to be linked to adiposity and insulin resistance in middle-aged participants. However, the association between leptin and metabolic syndrome independently of body fat and body fat distribution has not been evaluated in healthy elderly people. METHODS: We studied the independent relation between leptin and the components of the metabolic syndrome in 107 women aged 67-78 years with body mass index (BMI) ranging from 18.19 to 36.16 kg/m2. In all participants, we evaluated BMI, waist and hip circumferences, body composition by dual energy X-ray absorptiometry, fasting, and 2-hour glucose, lipids, insulin, homeostasis model assessment of insulin resistance (HOMA), systolic (SBP), diastolic blood pressure (DBP), and leptin. RESULTS: Significant correlation was found between leptin, BMI, waist circumference, fat mass, DBP, SBP, cholesterol, triglycerides, insulin, and HOMA. After adjusting for age and waist circumference, as well for age and fat mass, leptin was significantly related to insulin levels, HOMA, and cholesterol. In a stepwise multiple regression analysis using insulin levels or HOMA as dependent variables and age, waist circumference, fat mass, leptin, SBP, DBP, cholesterol, and triglycerides as independent variables, leptin entered the regression first, waist circumference second, and age third. CONCLUSION: Our study shows that leptin is significantly related to indices of adiposity in elderly women, and leptin is significantly associated with insulin levels, HOMA, and cholesterol independent of age, body fat, and fat distribution. Leptin, waist circumference, and age together explained 31% and 33% of insulin levels and HOMA variance, respectively, in healthy elderly women. 相似文献
994.
Nuzzo F Morabito A De Maio E Di Rella F Gravina A Labonia V Landi G Pacilio C Piccirillo MC Rossi E D'Aiuto G Thomas R Gori S Colozza M De Placido S Lauria R Signoriello G Gallo C Perrone F de Matteis A 《Critical reviews in oncology/hematology》2008,66(2):171-180
Within an ongoing multicentre phase 3 randomised trial (ELDA, cancertrials.gov ID: NCT00331097), early breast cancer patients, 65-79 years old, with average to high risk of recurrence, are randomly assigned to receive CMF (cyclophosphamide 600 mg/m2, methotrexate 40 mg/m2, fluorouracil 600 mg/m2, days 1-8) or docetaxel (35 mg/m2 days 1-8-15), every 4 weeks. Here we report an unplanned safety analysis prompted by an amendment introducing creatinine clearance as a tool to adjust methotrexate dose. Before such change, 101 patients with a median age of 70 were randomly assigned CMF (53 patients) or docetaxel (48 patients). At least one grades 3-4 toxic event of any type was reported in 40 (75.5%) and 19 (39.6%) patients with CMF and docetaxel, respectively (p=0.0002). Grades 3-4 hematological events were observed in 37 (69.8%) vs. 4 (8.3%) cases (p<0.0001) and grades 3-4 non-hematological toxicity in 12 (22.6%) vs. 15 (31.2%) patients (p=0.11), with CMF and docetaxel, respectively. A higher incidence of anemia, neutropenia, thrombocytopenia and febrile neutropenia was reported with CMF. Constipation, mucositis, nausea and vomiting were more common with CMF; diarrhoea, abdominal pain, dysgeusia, neuropathy and liver toxicity were more frequent with docetaxel. No significant interaction was found between the occurrence of severe toxicity and baseline variables, including creatinine clearance and geriatric activity scales. In conclusion, weekly docetaxel appears to be less toxic than CMF in terms of hematological toxicity. 相似文献
995.
996.
Pieruzzi F Munforti C Di Blasio A Busca G Dadone V Zanchetti A Golin R 《Journal of hypertension》2002,20(10):2039-2045
OBJECTIVE: The aim of the present study was to evaluate the role of the renal nerves in the regulation of neuronal nitric oxide synthase (nNOS) gene expression in normotensive rats on different sodium balance. METHODS: Thirty-six male Sprague-Dawley rats were divided into six experimental groups combining three diets with different NaCl content (normal, 0.4%; low, 0.04%; or high, 4.0%), and bilateral renal denervation or sham denervation. After 7 days of dietary treatment, all rats were sacrificed and plasma renin activity (PRA) measured. The nNOS and renin messenger RNA (mRNA) levels in the renal cortex were determined by semiquantitative polymerase chain reaction. RESULTS: PRA was higher in animals with low sodium diet compared with those with standard diet, while it was lower in animals with high sodium diet. Renal denervation decreased PRA in normal and low sodium groups, while it did not alter the PRA values in the high sodium group. The nNOS gene expression significantly increased in rats fed with the low sodium diet compared with the standard diet group, and it significantly decreased in rats with the high sodium diet. Renal denervation significantly reduced nNOS mRNA levels in rats receiving the low sodium diet, but did not significantly influence nNOS mRNA in normal and high sodium groups. Renin mRNA was influenced by diets and denervation in a parallel way to nNOS mRNA. CONCLUSION: The renal nerves mediate the increase of renin and nNOS mRNA during sodium restriction, while the suppression of nNOS and renin gene expression during a sodium load is independent of the presence of the renal nerves. The parallel changes in renin and nNOS mRNA during different sodium intakes suggest that nNOS can be part of the complex, and still largely unclarified, macula densa mechanism of renin regulation. 相似文献
997.
998.
The spectrum of pediatric eosinophilic esophagitis beyond infancy: a clinical series of 30 children 总被引:9,自引:0,他引:9
Orenstein SR Shalaby TM Di Lorenzo C Putnam PE Sigurdsson L Mousa H Kocoshis SA 《The American journal of gastroenterology》2000,95(6):1422-1430
OBJECTIVES: Eosinophilic esophagitis, previously confused with esophageal inflammation due to gastroesophageal reflux, has recently begun to be distinguished from it. We undertook this analysis of our large series of children with the condition to clarify its spectrum: its presenting symptoms; its relation to allergy, respiratory disease, and reflux; its endoscopic and histological findings; and its diagnosis and therapy. METHODS: We analyzed the details of our clinical series of 30 children with eosinophilic esophagitis, defining it as > or =5 eosinophils per high power field in the distal esophageal epithelium. Retrospective chart review was supplemented by prospective, blinded, duplicate quantitative evaluation of histology specimens, and by telephone contact with some families to clarify subsequent course. Presentation and analysis of the series as a whole is preceded by a case illustrating a typical presentation with dysphagia and recurrent esophageal food impactions. RESULTS: Presenting symptoms encompass vomiting, pain, and dysphagia (some with impactions or strictures). Allergy, particularly food allergy, is an associated finding in most patients, and many have concomitant asthma or other chronic respiratory disease. A subtle granularity with furrows or rings is newly identified as the endoscopic herald of histological eosinophilic esophagitis. Histological characteristics include peripapillary or juxtaluminal eosinophil clustering in certain cases. Association with eosinophilic gastroenteritis occurs, but is not common. Differentiation from gastroesophageal reflux disease is approached by analyzing eosinophil density and response to therapeutic trials. Therapy encompasses dietary elimination and anti-inflammatory pharmacotherapy. CONCLUSION: Awareness of the spectrum of eosinophilic esophagitis should promote optimal diagnosis and treatment of this elusive entity, both in children and in adults. 相似文献
999.
Aimaretti G Baffoni C Bellone S Di Vito L Corneli G Arvat E Benso L Camanni F Ghigo E 《The Journal of clinical endocrinology and metabolism》2000,85(10):3693-3699
Within an appropriate clinical context, severe GH deficiency (GHD) in adults has to be defined biochemically by provocative testing of GH secretion. Patients with childhood-onset GHD need retesting in late adolescence or young adulthood to verify whether they have to continue recombinant human GH treatment. GHRH + arginine (GHRH+ARG) is the most reliable alternative to the insulin-induced hypoglycemia test (ITT) as a provocative test for the diagnosis of GHD in adulthood, provided that appropriate cut-off limits are assumed (normal limits, 16.5 microg/L as 3rd and 9.0 microg/L as 1st centile). We studied the GH response to a single GHRH (1 microg/kg iv) + ARG (0.5 g/kg iv) test in 62 young patients who had undergone GH replacement in childhood, based on the following diagnosis: 1) organic hypopituitarism with GHD (oGHD) In = 18: 15 male (M), 3 female (F); age, 26.8+/-2.2 yr; GH peak < 10 microg/L after two classical tests]; 2) idiopathic isolated GHD (iGHD) [n = 23 (15 M, 8 F); age, 23.0+/-1.5 yr; GH peak < 10 microg/L after two classical tests]; and 3) GH neurosecretory dysfunction (GHNSD) [n = 21 (10 M, 11 F); age, 25.1+/-1.6 yr; GH peak > 10 microg/L after classical test but mGHc < 3 microg/L]. The GH responses to GHRH+ARG in these groups were also compared with that recorded in a group of age-matched normal subjects (NS) [n = 48 (20 M, 28 F); age, 27.7+/-0.8 yr]. Insulin-like growth factor I levels in oGHD subjects (61.5+/-13.7 microg/L) were lower (P < 0.001) than those in iGHD subjects (117.2+/-13.1 microg/L); the latter were lower than those in GHNSD subjects (210.2+/-12.9 microg/L), which, in turn, were similar to those in NS (220.9+/-7.1 microg/L). The mean GH peak after GHRH+ARG in oGHD (2.8+/-0.8 microg/L) was lower (P < 0.001) than that in iGHD (18.6+/-4.7 microg/L), which, in turn, was clearly lower (P < 0.001) than that in GHNSD (31.3+/-1.6 microg/L). The GH response in GHNSD was lower than that in NS (65.9+/-5.5 microg/L), but this difference did not attain statistical significance. With respect to the 3rd centile limit of GH response in young adults (i.e. 16.5 microg/L), retesting confirmed GHD in all oGHD, in 65.2% of iGHD, and in none of the GHNSD subjects. With respect to the 1st centile limit of GH response (i.e. 9.0 microg/L), retesting demonstrated severe GHD in 94% oGHD and in 52.1% of iGHD. All oGHD and iGHD with GH peak after GHRH+ARG lower than 9 microg/L had also GH peak lower than 3 microg/L after ITT. In the patients in whom GHD was confirmed by retesting, the mean GH peak after GHRH+ARG was higher than that after ITT (3.4+/-0.5 vs. 1.9+/-0.4). In conclusion, given appropriate cut-off limits, GHRH+ARG is as reliable as ITT for retesting patients who had undergone GH treatment in childhood. Among these patients, severe GHD in adulthood is generally confirmed in oGHD, is frequent in iGHD, but never occurs in GHNSD. 相似文献
1000.
Grottoli S Maccagno B Ramunni J Di Vito L Giordano R Gianotti L DeStefanis S Camanni F Ghigo E Arvat E 《Journal of endocrinological investigation》2002,25(5):420-425
Alprazolam (AL), a benzodiazepine which activates gamma-amino butyrric acid (GABA)-ergic receptors, exerts a clear inhibitory effect on the activity of the hypothalamo-pituitary-adrenal (HPA) axis and is able to markedly reduce the ACTH response to metyrapone-induced inhibition of glucocorticoid feedback. It has been suggested that its inhibitory action could be regulated by CRH or AVP mediated mechanisms. However, the effect of benzodiazepines on the HPA response to CRH or AVP is contradictory. It has been shown that benzodiazepines have specific receptors on the adrenal gland but it is unclear if they mediate biological effects in humans. In order to further clarify the mechanisms underlying the inhibitory effect of benzodiazepine on HPA axis in humans, we studied the effect of AL (0.02 mg/kg po at -90 min) or placebo in 7 healthy young volunteers (7 female, age: 26-34 yr; wt: 50-58 kg, BMI 20-22 kg/m2) on: 1) the ACTH and cortisol responses to hCRH (2.0 microg/kg iv at 0 min) or AVP (0.17 U/kg im at 0 min); 2) the cortisol, aldosterone and DHEA responses to ACTH 1-24 (0.06 and 250 microg iv at 0 and 60 min, respectively). After placebo, the ACTH and cortisol responses to hCRH (peaks, mean+/-SE: 29.8+/-4.4 pg/ml and 199.3+/-19.6 microg/l) were similar to those recorded after AVP (31.7+/-6.5 pg/ml and 164.8+/-18.0 microg/l); the cortisol response to 0.06 microg ACTH (190.4+/-11.8 microg/l) was similar to that recorded after hCRH and AVP but lower (p<0.01) than that after 250 microg ACTH (260.6+/-17.4 microg/l). AL did not modify the ACTH response to both hCRH (42.5+/-7.1 pg/ml) and AVP (33.3+/-2.7 pg/ml), which even showed a trend toward increase. AL also failed to significantly modify the cortisol response to both hCRH (156.3+/-12.7 microg/l) and AVP (119.4+/-14.5 microg/l), which, on the other hand, showed a trend toward decrease. The cortisol peaks after 0.06 microg ACTH were significantly reduced (p<0.02) by AL pre-treatment (115.0+/-7.7 microg/l) which, in turn, did not modify the cortisol response to the subsequent ACTH bolus (214.7+/-16.6 microg/l). The DHEA and aldosterone responses to all the ACTH doses were not significantly modified by AL. In conclusion, these data show that the HPA response to AVP as well as to hCRH is refractory to the inhibitory effect of AL which, in turn, blunts the cortisol response to low ACTH dose. These findings suggest that both CRH- and AVP-mediated mechanisms could underlie the CNS-mediated inhibitory effect of AL on HPA axis; in the meantime, these results suggest that benzodiazepines could also act on adrenal gland by blunting the sensitivity of the fasciculata zone to ACTH. 相似文献