79 resultados para Perinatal androgen blockade
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PURPOSE: This study (EORTC 30891) attempted to demonstrate equivalent overall survival in patients with localized prostate cancer not suitable for local curative treatment treated with immediate or deferred androgen ablation. PATIENTS AND METHODS: We randomly assigned 985 patients with newly diagnosed prostate cancer T0-4 N0-2 M0 to receive androgen deprivation either immediately (n = 493) or on symptomatic disease progression or occurrence of serious complications (n = 492). RESULTS: Baseline characteristics were well balanced in the two groups. Median age was 73 years (range, 52 to 81). At a median follow-up of 7.8 years, 541 of 985 patients had died, mostly of prostate cancer (n = 193) or cardiovascular disease (n = 185). The overall survival hazard ratio was 1.25 (95% CI, 1.05 to 1.48; noninferiority P > .1) favoring immediate treatment, seemingly due to fewer deaths of nonprostatic cancer causes (P = .06). The time from randomization to progression of hormone refractory disease did not differ significantly, nor did prostate-cancer specific survival. The median time to the start of deferred treatment after study entry was 7 years. In this group 126 patients (25.6%) died without ever needing treatment (44% of the deaths in this arm). CONCLUSION: Immediate androgen deprivation resulted in a modest but statistically significant increase in overall survival but no significant difference in prostate cancer mortality or symptom-free survival. This must be weighed on an individual basis against the adverse effects of life-long androgen deprivation, which may be avoided in a substantial number of patients with a deferred treatment policy.
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Thiazolidinediones (TZDs) such as pioglitazone and rosiglitazone are widely used as insulin sensitizers in the treatment of type 2 diabetes. In diabetic women with polycystic ovary syndrome, treatment with pioglitazone or rosiglitazone improves insulin resistance and hyperandrogenism, but the mechanism by which TZDs down-regulate androgen production is unknown. Androgens are synthesized in the human gonads as well as the adrenals. We studied the regulation of androgen production by analyzing the effect of pioglitazone and rosiglitazone on steroidogenesis in human adrenal NCI-H295R cells, an established in vitro model of steroidogenesis of the human adrenal cortex. Both TZDs changed the steroid profile of the NCI-H295R cells and inhibited the activities of P450c17 and 3betaHSDII, key enzymes of androgen biosynthesis. Pioglitazone but not rosiglitazone inhibited the expression of the CYP17 and HSD3B2 genes. Likewise, pioglitazone repressed basal and 8-bromo-cAMP-stimulated activities of CYP17 and HSD3B2 promoter reporters in NCI-H295R cells. However, pioglitazone did not change the activity of a cAMP-responsive luciferase reporter, indicating that it does not influence cAMP/protein kinase A/cAMP response element-binding protein pathway signaling. Although peroxisome proliferator-activated receptor gamma (PPARgamma) is the nuclear receptor for TZDs, suppression of PPARgamma by small interfering RNA technique did not alter the inhibitory effect of pioglitazone on CYP17 and HSD3B2 expression, suggesting that the action of pioglitazone is independent of PPARgamma. On the other hand, treatment of NCI-H295R cells with mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) inhibitor 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one (PD98059) enhanced promoter activity and expression of CYP17. This effect was reversed by pioglitazone treatment, indicating that the MEK/ERK signaling pathway plays a role in regulating androgen biosynthesis by pioglitazone.
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OBJECTIVE: Mesenchymal stem cells (MSCs) have a broad differentiation potential. We aimed to determine if MSCs are present in fetal membranes and placental tissue and to assess their potential to differentiate into neurogenic and mesodermal lineages. STUDY DESIGN: MSCs isolated from first and third trimester chorion and amnion and first trimester chorionic villi and characterized morphologically and by flourescence-activated cell sorting analysis. Their ability to mature under different culture conditions into various cells of mesodermal and neuroectodermal cell lines was assessed by immuno- and cytochemical staining. RESULTS: Independent of gestational age, cells isolated from fetal membranes and placenta showed typical MSC phenotype (positive for CD166, CD105, CD90, CD73, CD49e, CD44, CD29, CD13, MHC I; negative for CD14, CD34, CD45, MHC II) and were able to differentiate into mesodermal cells expressing cell markers/cytologic staining consistent with mature chondroblasts, osteoblasts, adipocytes, or myocytes and into neuronal cells presenting markers of various stages of maturation. The differentiation pattern was mainly dependent on cell type. CONCLUSION: Mesenchymal cells from chorion, amnion, and villous stroma can be differentiated into neurogenic, chondrogenic, osteogenic, adipogenic, and myogenic lineage. Placental tissue obtained during prenatal chorionic villous sampling or at delivery might be an ideal source for autologous stem cell graft for peripartum neuroregeneration and other clinical issues.
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Mammalian birth is accompanied by profound changes in metabolic rate that can be described in terms of body size relationship (Kleiber's rule). Whereas the fetus, probably as an adaptation to the low intrauterine pO2, exhibits an "inappropriately" low, adult-like specific metabolic rate, the term neonate undergoes a rapid metabolic increase up to the level to be expected from body size. A similar, albeit slowed, "switching-on" of metabolic size allometry is found in human preterm neonates whereas animals that are normally born in a very immature state are able to retard or even suppress the postnatal metabolic increase in favor of weight gain and O2 supply. Moreover, small immature mammalian neonates exhibit a temporary oxyconforming behavior which enhances their hypoxia tolerance, yet is lost to the extent by which the size-adjusted metabolic rate is "locked" by increasing mitochondrial density. Beyond the perinatal period, there are no other deviations from metabolic size allometry among mammals except in hibernation where the temporary "switching-off" of Kleiber's rule is accompanied by a deep reduction in tissue pO2. This gives support to the hypothesis that the postnatal metabolic increase represents an "escape from oxygen" similar to the evolutionary roots of mitochondrial respiration, and that the overall increase in specific metabolic rate with decreasing size might contribute to prevent tissues from O2 toxicity.
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BACKGROUND: Electrical stimulation of the P6 acupuncture point reduces the incidence of postoperative nausea and vomiting (PONV). Neuromuscular blockade during general anesthesia can be monitored with electrical peripheral nerve stimulation at the wrist. The authors tested the effect of neuromuscular monitoring over the P6 acupuncture point on the reduction of PONV. METHODS: In this prospective, double-blinded, randomized control trial, the authors investigated, with institutional review board approval and informed consent, 220 women undergoing elective laparoscopic surgery anesthetized with fentanyl, sevoflurane, and rocuronium. During anesthesia, neuromuscular blockade was monitored by a conventional nerve stimulator at a frequency of 1 Hz over the ulnar nerve (n = 110, control group) or over the median nerve (n = 110, P6 group) stimulating at the P6 acupuncture point at the same time. The authors evaluated the incidence of nausea and vomiting during the first 24 h. RESULTS: No differences in demographic and morphometric data were found between both groups. The 24-h incidence of PONV was 45% in the P6 acupuncture group versus 61% in the control group (P = 0.022). Nausea decreased from 56% in the control group to 40% in the P6 group (P = 0.022), but emesis decreased only from 28% to 23% (P = 0.439). Nausea decreased substantially during the first 6 h of the observation period (P = 0.009). Fewer subjects in the acupuncture group required ondansetron as rescue therapy (27% vs. 39%; P = 0.086). CONCLUSION: Intraoperative P6 acupuncture point stimulation with a conventional nerve stimulator during surgery significantly reduced the incidence of PONV over 24 h. The efficacy of P6 stimulation is similar to that of commonly used antiemetic drugs in the prevention of PONV.
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Although experimental prevention studies have suggested therapeutic potential of endothelin (ET) antagonists for the treatment of heart failure, the results of clinical trials using ET antagonists on top of standard heart failure medications have been largely disappointing. This experimental study investigated the effects of chronic ET(A) receptor blockade in long-term survivors of myocardial infarction who had developed stable chronic heart failure in the absence of other treatments. Systolic blood pressure, heart rate, organ weights of the right atrium and ventricle, and the lungs were determined, and tissue ET-1 peptide levels were measured in cardiac tissue, lung, and aorta. The results show that chronic blockade of ET(A) receptors stabilizes systolic blood pressure and reverses the heart failure-induced weight increases of right heart chambers and lung. The changes observed occurred independently of tissue ET-1 concentrations and heart rate, suggesting mechanisms independent of local cardiac or pulmonary ET-1 synthesis, which are yet to be identified.
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Secondary complications of diabetes mellitus often involve gastrointestinal dysfunction. In the experimental Goto Kakizaki rat, a model of Type II diabetes, hyperglycaemia and reduced glucose clearance is associated with elevated plasma endothelin (ET)-1 levels and selective decreases in nitric oxide synthase in circular muscle, longitudinal muscle and neuronal elements of the gastrointestinal tract. Functionally, this is accompanied by decreased nitrergic relaxatory responses of jejunal longitudinal muscle to tetrodotoxin-sensitive electrical field stimulation. Long-term treatment with a selective ET A-type receptor antagonist, markedly reduced hyperglycaemia and restored plasma glucose clearance rates towards normal. This was associated with a restoration of N(G)-nitro-L-arginine methyl ester-sensitive relaxatory responses of jejunal longitudinal muscle to electrical field stimulation. The results indicate that beneficial effects of ETA receptor blockade on gastrointestinal function may result from an improvement in insulin sensitivity with concomitant reduction of the severity of hyperglycaemia. ETA receptor blockade may represent a new therapeutic principle for improving glucose tolerance in Type II diabetes and could be beneficial in alleviating or preventing hyperglycaemia-related secondary complications in this condition.
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BACKGROUND: Excitotoxic neuronal injury by action of the glutamate receptors of the N-methyl-d-aspartate (NMDA) subtype have been implicated in the pathogenesis of brain damage as a consequence of bacterial meningitis. The most potent and selective blocker of NMDA receptors containing the NR2B subunit is (R,S)-alpha-(4-hydroxyphenyl)-beta-methyl-4-(phenylmethyl)-1-piperid inepropanol (RO 25-6981). Here we evaluated the effect of RO 25-6981 on hippocampal neuronal apoptosis in an infant rat model of meningitis due to Streptococcus pneumoniae. Animals were randomized for treatment with RO 25-6981 at a dosage of either 0.375 mg (15 mg/kg; n = 28) or 3.75 mg (150 mg/kg; n = 15) every 3 h or an equal volume of sterile saline (250 microl; n = 40) starting at 12 h after infection. Eighteen hours after infection, animals were assessed clinically and seizures were observed for a period of 2 h. At 24 h after infection animals were sacrificed and brains were examined for apoptotic injury to the dentate granule cell layer of the hippocampus. RESULTS: Treatment with RO 25-6981 had no effect on clinical scores, but the incidence of seizures was reduced (P < 0.05 for all RO 25-6981 treated animals combined). The extent of apoptosis was not affected by low or high doses of RO 25-6981. Number of apoptotic cells (median [range]) was 12.76 [3.16-25.3] in animals treated with low dose RO 25-6981 (control animals 13.8 [2.60-31.8]; (P = NS) and 9.8 [1.7-27.3] (controls: 10.5 [2.4-21.75]) in animals treated with high dose RO 25-6981 (P = NS). CONCLUSIONS: Treatment with a highly selective blocker of NMDA receptors containing the NR2B subunit failed to protect hippocampal neurons from injury in this model of pneumococcal meningitis, while it had some beneficial effect on the incidence of seizures.
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BACKGROUND: /st> Retrobulbar anaesthesia allows eye surgery in awake patients. Severe complications of the blind techniques are reported. Ultrasound-guided needle introduction and direct visualization of the spread of local anaesthetic may improve quality and safety of retrobulbar anaesthesia. Therefore, we developed a new ultrasound-guided technique using human cadavers. METHODS: /st> In total, 20 blocks on both sides in 10 embalmed human cadavers were performed. Using a small curved array transducer and a long-axis approach, a 22 G short bevel needle was introduced under ultrasound guidance lateral and caudal of the eyeball until the needle tip was seen 2 mm away from the optic nerve. At this point, 2 ml of contrast dye as a substitute for local anaesthetic was injected. Immediately after the injection, the spread of the contrast dye was documented by means of CT scans performed in each cadaver. RESULTS: /st> The CT scans showed the distribution of the contrast dye in the muscle cone and behind the posterior sclera in all but one case. No contrast dye was found inside the optic nerve or inside the eyeball. In one case, there could be an additional trace of contrast dye behind the orbita. CONCLUSIONS: /st> Our new ultrasound-guided technique has the potential to improve safety and efficacy of the procedure by direct visualization of the needle placement and the distribution of the injected fluid. Furthermore, the precise injection near the optic nerve could lead to a reduction of the amount of the local anaesthetic needed with fewer related complications.
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OBJECTIVES: We compared androgen and gonadotropin values in HIV-infected men who did and did not develop lipoatrophy on combination antiretroviral therapy (cART). METHODS: From a population of 136 treatment-naïve male Caucasians under successful zidovudine/lamivudine-based cART, the 10 patients developing lipoatrophy (cases) were compared with 87 randomly chosen controls. Plasma levels of free testosterone (fT), dehydroepiandrosterone (DHEA), follicle-stimulating hormone and luteinizing hormone (LH) were measured at baseline and after 2 years of cART. RESULTS: At baseline, 60% of the cases and 71% of the controls showed abnormally low fT values. LH levels were normal or low in 67 and 94% of the patients, respectively, indicating a disturbance of the hypothalamic-pituitary-gonadal axis. fT levels did not significantly change after 2 years of cART. Cases showed a significant increase in LH levels, while controls showed a significant increase in DHEA levels. In a multivariate logistic regression model, lipoatrophy was associated with higher baseline DHEA levels (P=0.04), an increase in LH levels during cART (P=0.001), a lower body mass index and greater age. CONCLUSIONS: Hypogonadism is present in the majority of HIV-infected patients. The development of cART-related lipoatrophy is associated with an increase in LH and a lack of increase in DHEA levels.
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Most genetic diseases of the lymphohematopoietic system, including hemoglobinopathies, can now be diagnosed early in gestation. However, as yet, prenatal treatment is not available. Postnatal therapy by hematopoietic stem cell (HSC) transplantation from bone marrow, mobilized peripheral blood, or umbilical cord blood is possible for several of these diseases, in particular for the hemoglobinopathies, but is often limited by a lack of histocompatible donors, severe treatment-associated morbidity, and preexisting organ damage that developed before birth. In-utero transplantation of allogeneic HSC has been performed successfully in various animal models and recently in humans. However, the clinical success of this novel treatment is limited to diseases in which the fetus is affected by severe immunodeficiency. The lack of donor cell engraftment in nonimmunocompromised hosts is thought to be due to immunologic barriers, as well as to competitive fetal marrow population by host HSCs. Among the possible strategies to circumvent allogeneic HLA barriers, the use of gene therapy by genetically corrected autologous HSCs in the fetus is one of the most promising approaches. The recent development of strategies to overcome failure of efficient transduction of quiescent hematopoietic cells using new vector constructs and transduction protocols opens new perspectives for gene therapy in general, as well as for prenatal gene transfer in particular. The fetus might be especially susceptible for successful gene therapy approaches because of the developing, expanding hematopoietic system during gestation and the immunologic naiveté early in gestation, precluding immune reaction towards the transgene by inducing tolerance. Ethical issues, in particular regarding treatment safety, must be addressed more closely before clinical trials with fetal gene therapy in human pregnancies can be initiated.
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A levoatrial cardinal vein is a rare cardiovascular anomaly that may be present in malformed hearts with severe left heart obstruction and restrictive interatrial communication. We report the prenatal diagnosis at 23 weeks of a fetus with mitral atresia, double-outlet right ventricle, premature closure of the foramen ovale and a levoatrial cardinal vein draining into the innominate vein. In a prior examination performed elsewhere the levoatrial cardinal vein had been interpreted as an aortic arch perfused retrogradely, and hypoplastic left heart syndrome with aortic atresia had been diagnosed. Prenatal management, induction at 38 weeks and postnatal examinations and treatment are reported. To the best of our knowledge, this is the first reported prenatal diagnosis of this embryological vessel, presenting a potential pitfall for prenatal echocardiography.
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CONTEXT: Androgen deprivation therapy (ADT) is increasingly used for the treatment of prostate cancer (PCa), even in clinical settings in which there is no evidence-based proof of prolonged overall survival (OS). ADT, however, may be associated with numerous side effects, including an increased therapy-related cardiovascular mortality. OBJECTIVE: To discuss different clinical settings in which ADT is currently used and to critically weigh the benefits of ADT against its possible side effects. EVIDENCE ACQUISITION: A MEDLINE search was conducted to identify original articles and review articles addressing the efficacy and side effects of ADT for the treatment of PCa. Keywords consisted of prostate cancer, hormonal therapy, adverse effects, radical prostatectomy, and radiotherapy. The articles with the highest level of evidence for the various examined end points were identified with the consensus of all authors and were reviewed. EVIDENCE SYNTHESIS: Even short-term use of ADT may lead to numerous side effects, such as osteoporosis, obesity, sarcopenia, lipid alterations, insulin resistance, and increased risk for diabetes and cardiovascular morbidity. Despite these side effects, ADT is commonly used in various clinical settings in which a clear effect on improved OS has not been shown. CONCLUSIONS: ADT is associated with an increased risk of multiple side effects that may reduce quality of life and/or OS. Consequently, these issues should be discussed in detail with patients and their families before initiation of ADT. ADT should be used with knowledge of its potential long-term side effects and with possible lifestyle interventions, especially in settings with the highest risk-benefit ratio, to alleviate comorbidities.