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The aim of the present study was to evaluate the effect of long-term (12 months) administration of raloxifene hydrochloride (60 mg/day) on the steroid production of the adrenal cortex and on the hypothalamic-pituitary-adrenal axis in postmenopausal women. We performed a basal evaluation, a corticotropin releasing factor (CRF) (100 microg i.v. bolus) test and a dexamethasone (DXM) (0.25 mg) suppression-adrenocorticotropic hormone (ACTH) (10 microg i.v. bolus) stimulation test in 11 postmenopausal women, before and after 3, 6 and 12 months of raloxifene treatment. Raloxifene administration significantly modified circulating levels of adrenal steroids, decreasing cortisol (-24%), dehydroepiandrosterone (DHEA) (-36%), and its sulfate (DHEAS) (-41%), and androstenedione (-29%), and increasing circulating allopregnanolone (+39%) levels. Progesterone and 17OH-progesterone levels remained unmodified, while estradiol and estrone levels showed a significant decrease (-51% for estradiol and -61% for estrone). We also observed an increase in circulating ACTH (+58%) and beta-endorphin (+120%). No modifications in the hormonal responses to CRF were observed during the treatment. DXM significantly suppressed circulating steroids at any time with a lower suppression of cortisol from the third month and a higher suppression of DHEA at 12 months. ACTH administration was associated with a significantly blunted cortisol response from the sixth month and a significantly increased response of allopregnanolone from the third month. The present data exclude a raloxifene effect on pituitary sensitivity to CRF and demonstrate a reduced adrenal sensitivity to ACTH, sustained by the opposite changes in basal cortisol and Delta5 androgens, which were reduced, and in ACTH and beta-endorphin, which were increased, as well by the reduced response of cortisol to the direct ACTH stimulus. The reduction of circulating cortisol levels and cortisol response to the ACTH challenge suggests that raloxifene protects against the neurotoxic effects of endogenous glucocorticoids. Furthermore, the progressive increase in basal allopregnanolone and its increased response to ACTH indicate that chronic raloxifene administration exerts direct effects on the pattern of adrenal enzymes, leading to specific changes in the circulating levels of this anxiolytic progesterone metabolite. The important reduction in the circulating levels of estradiol and estrone under long-term raloxifene administration may represent a further mechanism by which this molecule may exert a protective effect against breast and endometrial malignancies.  相似文献   
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A case of Cushing's syndrome in a 24-yr-old homosexual with an AIDS-related complex is reported. In this patient certain symptoms common to both diseases, i.e. weakness, myalgia and muscle atrophy were accentuated, whereas other symptoms pathognomic of the human immunodeficiency virus (HIV) infection, i.e. lymphoadenopathies and weight loss, were less pronounced by the high levels of circulating adrenal steroids. Ketoconazole was administered po in order to block adrenal steroidogenesis, the drug caused a remarkable fall of cortisol serum concentrations, but was unable to modify significantly the immunological pattern of the patient. Our data suggest that changes of serum adrenal steroid levels have little effect on the immune network of patients with AIDS.  相似文献   
5.
Normal sleep is associated to physiological nocturnal rises in Interleukin 1 beta (IL 1 beta) secretion. The 24 h pattern of IL 1 beta, beta-Endorphin (beta-EPH), ACTH and cortisol (F) production was evaluated in four male healthy volunteers. Two subjects were unable to sleep, due to the stress of the experiment; in these cases, no detectable plasma IL 1 beta secretion, both diurnal and nocturnal, was present, beta-EPH plasma levels were significantly higher (p < 0.01) than in the subjects who slept regularly and, in one case, increased F plasma levels were also reported. A strong negative correlation between IL 1 beta and beta-EPH plasma levels was present in all the cases. In conclusion, stress-induced sleep alterations might deeply affect both diurnal and nocturnal IL 1 beta plasma secretion, probably due to the hypothalamus-pituitary-adrenal axis (HPAA) activation, and beta-EPH might be the reliable marker of the stress-induced HPAA activation level.  相似文献   
6.
Stapled hemorrhoidopexy is widely accepted to treat hemorrhoids, but serious complications have been reported. In this prospective audit, we correlated clinical outcome with pathological findings. From January 2003 to April 2007, 94 patients underwent hemorrhoidopexy. Macroscopic appearance of the specimen (shape, size, and depth) was recorded. Microscopically, the presence of columnar, transitional, and squamous epithelium, the involvement of circular/longitudinal smooth muscle, and features of mucosal prolapse were assessed. Clinical outcome was evaluated by a validated questionnaire. Postoperative pain, secretion, and bleeding durations were 12.7 +/− 10.6, 5.6 +/− 9.6, and 6.3 +/− 8.4 days. Patient’s return to work averaged 16.7 +/− 10.7 days. Fissure, skin tags, and anal strictures were observed in 23.4%. Seven patients experienced pain for a significantly longer period of time. All specimens contained columnar mucosa, but 29.8% contained columnar and transitional epithelium and 12.8% contained columnar, anal transitional, and stratified squamous epithelium. Smooth muscle was observed in 62.7%. Pain was significantly increased if transitional epithelium was present in the specimen. No correlation or differences were observed if smooth muscle was present, although postoperative bleeding was more frequent. Hemorrhoidopexy is safe and effective. The specimen should always be sent for pathology examination. Only columnar epithelium should be present and, although the presence of smooth muscle does not influence the outcome in terms of functional results, its presence may play a role in postoperative bleeding. Presented as poster at the Digestive Disease Week, May 2007, Washington, USA  相似文献   
7.
Background Recently, it has been demonstrated that surgical treatment of hemorrhoids in a day-care basis is possible and safe. The aim of this study was to compare the Longo stapled hemorrhoidopexy (SH) and the Milligan–Morgan hemorrhoidectomy (MMH). Methods One hundred seventy one patients (95 cases in SH group and 76 cases in MMH group) entered the study: 83 cases were III degree hemorrhoids, 88 IV degree. A priori and a post hoc power analysis were performed. Results, prospectively collected, were compared using chi squared test and student t test. Visual analog scale was used for pain evaluation. Postoperative pain, duration of pain, wound secretion, bleeding, resumption of a normal lifestyle, and postoperative complication were evaluated. Results Surgical time was 28.41 ± 10.78 for MMH and 28.30 ± 13.28 min in SH (P = 0.94). Postoperative pain was not different between MMH and SH during the first two postoperative days (4.73 ± 2.91 vs 5.1 ± 3.048; P = 0.4), during the following 6 days, patients treated with SH had less pain (4.63 ± 2.04 in MMH vs 3.60 ± 2.35 in SH; P = 0.006). In the SH group, seven patients needed further hospital stay for complicated course. SH showed higher incidence of anal fissure compared with MMH (6.3% vs 0%; P = 0.025) but no differences in urinary retention, anal stricture, urgency, or anal hemorrhage. Conclusions This study confirms that SH is associated with less postoperative pain and shorter postoperative symptoms, compared with MMH. SH may be a viable addition to the therapy for hemorrhoids with some advantages in early postoperative pain and some disadvantages in postoperative complications and costs.  相似文献   
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The purpose of this study was to examine the effect of first metatarsophalangeal arthrodesis on the sagittal plane orientation of the first ray and the medial longitudinal arch. Lateral weightbearing radiographs of 48 patients (54 feet) having undergone the procedure were retrospectively reviewed. Patients were separated into three groups based on their preoperative diagnosis: hallux rigidus, hallux valgus, or rheumatoid forefoot deformity. First metatarsal declination, talometatarsal, talar declination, calcaneal inclination, and talocalcaneal angles were measured on pre- and postoperative radiographs. Multivariate analysis of variance determined that there was a significant postoperative change (p < .001) in angular measurements, particularly in the first metatarsal declination, talometatarsal, and talocalcaneal angles. There was also a significant difference (p < .01) in the angular measurements between the hallux rigidus group and the other two groups. However, the amount of change from pre- to postoperatively did not vary significantly between the groups. A calculation of Pearson correlation coefficients found no significant correlation between the hallux dorsiflexion angle and changes in angular measurements. The radiographic changes found in this study support Hicks' windlass model: fixed dorsiflexion of the hallux causes plantarflexion of the first ray and an increase in the medial longitudinal arch.  相似文献   
10.
In this study, a replicative fowl adenovirus serotype 1 (CELO) recombinant expressing chicken interferon-gamma (ChIFN-gamma) was constructed. In the engineered recombinant, the ChIFN-gamma gene was placed under the control of cytomegalovirus (CMV) promoter. The ChIFN-gamma expression cassette was inserted in the right end of the CELO genome (D fragment), which was able to carry the largest insertion of foreign DNA without affecting the replication functions of the vector. The recombinant ChIFN-gamma (rChIFN-gamma) produced in the CELO-virus expression system was characterized by comparing its biologic activities with that of rChIFN-gamma produced via the baculovirus expression system (Bac-ChIFN-gamma). CELO-ChIFN-gamma inhibited the replication of cytolytic virus in chicken embryo fibroblasts (CEFs) and activated macrophages in a better manner than did Bac-ChIFN-gamma . Moreover, the in vitro and in vivo stability of the CELO-derived rChIFN-gamma was considerably higher than that of the Bac-ChIFN-gamma. The CELO-ChIFN-gamma recombinant vector was able to replicate in vitro in the loghorn male hepatoma (LMH) hepatocyte cell line and to produce detectable levels of recombinant cytokine in supernatant as early as 90 min post-infection. Therefore, the CELO-virus expression system is an appropriate system for high-level expression of biologically active and stable ChIFN-gamma.  相似文献   
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