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111.

Background

Acromegaly is an excessive GH secretion, which in most cases, is caused by a pituitary GH-secreting adenoma. Traditional treatment of acromegaly consists of surgery, drug therapy, and eventually radiotherapy. The aim of this retrospective study is to evaluate the results of transsphenoidal endoscopic surgery in a group of patients with intrasellar GH adenoma who were operated by a pituitary specialist surgeon. We shall then argue about the economical advantages, for the NHS of a developing country, between surgical and medical treatment.

Methods

We have analyzed data from 33 patients with intrasellar GH tumor who had been referred to the neuroendocrine department of the HGF, Brazil. The patients underwent a transsphenoidal endoscopic adenomectomy for acromegaly between 2000 and 2005. Their ages were between 20 and 67 years (mean, 44 years) at the moment of surgery. No cavernous sinus invasion was present. Follow-up was a median of 2 years (range, 12 months-6 years).

Results

All 33 patients had intrasellar adenoma, 84.84% of patients achieved remission by surgery. One patient was operated twice and reached hormonal normalization. Five patients still had the disease and refused a second surgery. A treatment with octreotide was started for these 5 patients and resulted in an adequate control of GH and IGF-1 levels. No patients had radiotherapy.

Conclusion

Our patients, with intrasellar GH tumor, operated by a pituitary specialist neurosurgeon had remission rates approaching those obtained by most specialized neurosurgical centers worldwide. For equal results, our study shows that the surgical treatment is the best issue for the patient and for the NHS.  相似文献   
112.
BACKGROUND: Eosinophils have been identified in tissues from patients with Crohn's disease (CD) and ulcerative colitis (UC) but whether they contribute to IBD pathogenesis is unknown. This study aimed to investigate the functional activity and morphological aspects of peripheral-blood eosinophils from IBD patients compared to those from healthy volunteers (HVs). METHODS: Eosinophils from HVs and CD and UC patients were purified using a Percoll gradient and then a immunomagnetic cell separator. Functional activity in inactivated and previously activated cells was investigated by measuring adhesion to fibronectin and chemotaxis to fMLP, and degranulation was measured by release of eosinophil peroxidase (EPO). Cell morphology was investigated using electron microscopy. RESULTS: Eosinophil adhesion to human fibronectin in both inactivated and PAF-stimulated and PMA-stimulated eosinophils was markedly higher in patients with CD than in either patients with UC or HVs. Similarly, the chemotactic response was markedly higher in eosinophils isolated from CD patients than in those isolated from UC patients or HVs. Baseline EPO release was higher in eosinophils isolated from UC patients than in those isolated from HVs or CD patients. Stimulation with fMLP or PMA did not further increase EPO release in cells from UC or CD patients. Comparable expression of MAC- 1 and VLA-4 adhesion molecules was observed on the surfaces of eosinophils from all groups, and an greater number of granules was noted in the eosinophils from UC patients than in those from CD patients. CONCLUSIONS: Our results indicate that peripheral-blood eosinophils are potentially primed and activated in IBD patients. Whether the differences in the morphology and functional responses of eosinophil from UC and CD patients reflect differences in disease phenotype remains to be elucidated.  相似文献   
113.
BACKGROUND: Hepatitis B may show a more aggressive course after kidney transplantation, but the factors associated with the progression of fibrosis in this group have not been identified. OBJECTIVES: To determine the influence of hepatitis B virus (HBV) viral load and host-related factors on the progression of hepatic fibrosis in hepatitis B virus-infected renal transplant recipients. PATIENTS AND METHODS: Renal transplant patients positive for HBV surface antigen (HBsAg) and submitted to a liver biopsy because of evidence of viral replication were included. Patients with advanced fibrosis (METAVIR F3-F4) were compared with patients with mild fibrosis (F0-F2) regarding sex, age, estimated time since infection, post-transplant time, donor type, history of renal transplantation, alanine aminotransferase, anti-hepatitis C virus, HBeAg and quantitative hepatitis B virus-DNA. Logistic regression analysis was applied to identify variables independently associated with more advanced fibrosis. RESULTS: Fifty-five patients (75% men, 41+/-11 years) with a mean post-transplant time of 5+/-4 years were included. HBeAg was detected in 67% of the patients and anti-hepatitis C virus in 35%. The median hepatitis B virus-DNA level was 2.8 x 10(8) copies/ml. Seventeen (31%) patients had advanced fibrosis. Using logistic regression analysis, the only variable that showed an independent association with more advanced stages of fibrosis was post-transplant time (P=0.03, odds ratio: 1.2, 95% confidence interval: 1.02-1.45). CONCLUSION: Hepatitis B virus viral load, although very high, and hepatitis B virus/hepatitis C virus coinfection are not related to the intensity of liver fibrosis in renal transplant patients infected with hepatitis B virus. Post-transplant time was the only factor independently associated with more advanced liver fibrosis, suggesting the influence of immunosuppression on the progression of liver disease in these patients.  相似文献   
114.
BACKGROUND: Interferon monotherapy significantly reduces the chronicity rate of acute hepatitis C in nonuremic patients. In this clinical study, we evaluated the efficacy and tolerance of interferon-alpha therapy for acute hepatitis C in hemodialysis patients. METHODS: Patients with acute hepatitis C, established on the basis of seroconversion to anti-hepatitis C virus and the presence of hepatitis C virus RNA, received a low dose of interferon-alpha (3 MU three times per week) for 12 months or a high dose (5 MU three times per week, preceded by a daily induction dose) for 6 months. Response to treatment was defined as undetectable hepatitis C virus RNA at the end of treatment and sustained virological response was defined as persistent negative hepatitis C virus RNA 6 months after the end of treatment. RESULTS: Twenty-three patients were treated, 16 with a low dose of interferon-alpha and seven with a high dose. At the end of treatment, hepatitis C virus RNA was undetectable in 16/23 patients (70%). Of these, 6/23 patients (26%) relapsed and 10/23 (43%) maintained a sustained virological response (38% in lower doses vs. 57% in higher doses). Treatment was well tolerated and only three patients discontinued therapy (13%). CONCLUSION: Interferon-alpha within the first year after acute hepatitis C in hemodialysis patients was found to be safe and effective, inducing a sustained virological response in 43% of cases. This study supports the routine indication of acute hepatitis C treatment with interferon-alpha for hemodialysis patients, and higher doses administered for a shorter period of time should be tried according to the tolerance of the patients.  相似文献   
115.
116.
Fabry disease (OMIM 301500) is a rare X-linked recessive disorder caused by mutations in the alpha-galactosidase gene (GLA). Loss of alpha-galactosidase (alpha-Gal) activity leads to the abnormal accumulation of glycosphingolipids in lysosomes predominantly of vascular endothelial cells. Clinically the disorder presents with angiokeratomas, clouding of the cornea, and renal, cardiac, and cerebrovascular complications. In addition, there is an increased incidence of neuropathic pain in Fabry patients. In this study, we investigated the implications of loss of alpha-galactosidase A activity on sensorimotor function and peripheral nervous system. Similar to the described in Fabry disease patients, the sensorimotor assessment of Fabry mice revealed diminished locomotor activity and warm hypoalgesia as assessed in the hot-plate. Moreover Fabry mice displayed alterations both in balance and co-ordination. By histological analysis, the cyto-architecture of Fabry mice sciatic nerves showed an increase in mean cross-sectional area accompanied by a decrease in the density of non-myelinated fibers as well as a trend for a decreased number of small myelinated fibers, a well established feature of Fabry disease. A relative preservation of large myelinated fibers and nerve conduction velocity measurements was observed. Our findings demonstrate for the first time that Fabry knockout mice have Gb3 accumulation in the peripheral nervous system, alterations in sensorimotor function, hypoalgesia and no impairment of motor nerve conduction.  相似文献   
117.
Pterocaulon polystachyum DC is a native species to southern Brazil, Paraguay, Uruguay and northeastern Argentina. It is utilized to treat animal problems popularly diagnosed as "mycoses". The antifungal and amebicidal activity of its hexane extract has been previously reported, although there are no studies confirming the safety of this plant for therapeutic purposes to date. Hence, this study investigates the toxic effects of a hexane extract of Pterocaulon polystachyum administered as acute and subacute oral treatments. After acute treatment the extract caused alterations in biochemical parameters, morphological alterations in tissues and was genotoxic, according to the comet assay; neither mortality nor visible signs of lethality were seen in mice. Similarly subacute treatment caused important differences in biochemical parameters and tissues, between control and treated groups. The results also revealed genotoxicity in kidney tissue, though no mutagenicity was detected by the micronucleus test. No animal died during the treatment period.  相似文献   
118.
119.
The acute toxicity of glyphosate herbicide was tested on the four species of freshwater phytoplankton, Scenedesmus acutus, Scenedesmus subspicatus, Chlorella vulgaris and Chlorella saccharophila. Herbicide concentrations eliciting a 50% growth reduction over 72 h (EC50) ranged from 24.5 to 41.7 mg L−1, whilst a 10% growth inhibition is achieved by herbicide concentrations ranging from 1.6 to 3.0 mg L−1, difficult to find neither in paddy fields (it is not used in rice) nor in the lake of the Albufera Natural Park. Chorella species are less sensitive to the herbicide than Scenedesmus species. It can be concluded that glyphosate has a low potential risk for the tested organisms.  相似文献   
120.
PURPOSE: This study analyzed the continued nursing education process in three university hospitals in southern Brazil. Its theoretical reference was centered upon the problematization pedagogy of Freire and the levels of practice of Vázquez. METHODS: This was a qualitative case study, based on multiple holistic cases. The data were collected through document analysis, observation of scenarios, and semistructured interviews with 22 nursing employees. RESULTS: The thematic analysis evidenced the continued nursing education process, highlighting initiatives such as the creation of the Center for Nursing Education and Research, the Permanent Nursing Education Center, and the Continued Nursing Education Program. CONCLUSION: This study serves as an important tool for the transformation of the reality of health care subjects and institutions.  相似文献   
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