123 resultados para Juvenile hormone
Resumo:
Introduction Juvenile idiopathic arthritis (JIA) is a heterogeneous disease characterized by chronic joint inflammation of unknown cause in children. JIA is an autoimmune disease and small numbers of auto-antibodies have been reported in JIA patients. The identification of antibody markers could improve the existing clinical management of patients. Methods A pilot study was performed on the application of a high-throughput platform, nucleic acid programmable protein arrays (NAPPA), to assess the levels of antibodies present in the systemic circulation and synovial joint of a small cohort of juvenile arthritis patients. Plasma and synovial fluid from ten JIA patients was screened for antibodies against 768 proteins on NAPPA. Results Quantitative reproducibility of NAPPA was demonstrated with >0.95 intra- and inter- array correlations. A strong correlation was also observed for the levels of antibodies between plasma and synovial fluid across the study cohort (r=0.96). Differences in the levels of 18 antibodies were revealed between sample types across all patients. Patients were segregated into two clinical subtypes with distinct antibody signatures by unsupervised hierarchical cluster analysis. Conclusions NAPPA provides a high-throughput quantitatively reproducible platform to screen for disease specific autoantibodies at the proteome level on a microscope slide. The strong correlation between the circulating antibody levels and those of the inflamed joint represents a novel finding and provides confidence to use plasma for discovery of autoantibodies in JIA, thus circumventing the challenges associated with joint aspiration. We expect that autoantibody profiling of JIA patients on NAPPA could yield antibody markers that can act as criteria to stratify patients, predict outcomes and understand disease etiology at the molecular level.
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Background: As trials of 5 years of tamoxifen in early breast cancer mature, the relevance of hormone receptor measurements (and other patient characteristics) to long-term outcome can be assessed increasingly reliably. We report updated meta-analyses of the trials of 5 years of adjuvant tamoxifen.
Methods: We undertook a collaborative meta-analysis of individual patient data from 20 trials (n=21457) in early breast cancer of about 5 years of tamoxifen versus no adjuvant tamoxifen, with about 80% compliance. Recurrence and death rate ratios (RRs) were from log-rank analyses by allocated treatment.
Findings: In oestrogen receptor (ER)-positive disease (n=10 645), allocation to about 5 years of tamoxifen substantially reduced recurrence rates throughout the first 10 years (RR 0.53 [SE 0.03] during years 0-4 and RR 0.68 [0.06] during years 5-9 [both 2p<0.00001]; but RR 0.97 [0.10] during years 10-14, suggesting no further gain or loss after year 10). Even in marginally ER-positive disease (10-19 fmol/mg cytosol protein) the recurrence reduction was substantial (RR 0.67 [0.08]). In ER-positive disease, the RR was approximately independent of progesterone receptor status (or level), age, nodal status, or use of chemotherapy. Breast cancer mortality was reduced by about a third throughout the first 15 years (RR 0.71 [0.05] during years 0-4, 0.66 [0.05] during years 5-9, and 0.68 [0.08] during years 10-14; p<0.0001 for extra mortality reduction during each separate time period). Overall non-breast-cancer mortality was little affected, despite small absolute increases in thromboembolic and uterine cancer mortality (both only in women older than 55 years), so all-cause mortality was substantially reduced. In ER-negative disease, tamoxifen had little or no effect on breast cancer recurrence or mortality.
Interpretation: 5 years of adjuvant tamoxifen safely reduces 15-year risks of breast cancer recurrence and death. ER status was the only recorded factor importantly predictive of the proportional reductions. Hence, the absolute risk reductions produced by tamoxifen depend on the absolute breast cancer risks (after any chemotherapy) without tamoxifen.
Funding: Cancer Research UK, British Heart Foundation, and Medical Research Council.
Resumo:
BACKGROUND:
Long-term hormone therapy alone is standard care for metastatic or high-risk, non-metastatic prostate cancer. STAMPEDE--an international, open-label, randomised controlled trial--uses a novel multiarm, multistage design to assess whether the early additional use of one or two drugs (docetaxel, zoledronic acid, celecoxib, zoledronic acid and docetaxel, or zoledronic acid and celecoxib) improves survival in men starting first-line, long-term hormone therapy. Here, we report the preplanned, second intermediate analysis comparing hormone therapy plus celecoxib (arm D) with hormone therapy alone (control arm A).
METHODS:
Eligible patients were men with newly diagnosed or rapidly relapsing prostate cancer who were starting long-term hormone therapy for the first time. Hormone therapy was given as standard care in all trial arms, with local radiotherapy encouraged for newly diagnosed patients without distant metastasis. Randomisation was done using minimisation with a random element across seven stratification factors. Patients randomly allocated to arm D received celecoxib 400 mg twice daily, given orally, until 1 year or disease progression (including prostate-specific antigen [PSA] failure). The intermediate outcome was failure-free survival (FFS) in three activity stages; the primary outcome was overall survival in a subsequent efficacy stage. Research arms were compared pairwise against the control arm on an intention-to-treat basis. Accrual of further patients was discontinued in any research arm showing safety concerns or insufficient evidence of activity (lack of benefit) compared with the control arm. The minimum targeted activity at the second intermediate activity stage was a hazard ratio (HR) of 0·92. This trial is registered with ClinicalTrials.gov, number NCT00268476, and with Current Controlled Trials, number ISRCTN78818544.
FINDINGS:
2043 patients were enrolled in the trial from Oct 17, 2005, to Jan 31, 2011, of whom 584 were randomly allocated to receive hormone therapy alone (control group; arm A) and 291 to receive hormone therapy plus celecoxib (arm D). At the preplanned analysis of the second intermediate activity stage, with 305 FFS events (209 in arm A, 96 in arm D), there was no evidence of an advantage for hormone therapy plus celecoxib over hormone therapy alone: HR 0·94 (95% CI 0·74-1·20). [corrected]. 2-year FFS was 51% (95% CI 46-56) in arm A and 51% (95% CI 43-58) in arm D. There was no evidence of differences in the incidence of adverse events between groups (events of grade 3 or higher were noted at any time in 123 [23%, 95% CI 20-27] patients in arm A and 64 [25%, 19-30] in arm D). The most common grade 3-5 events adverse effects in both groups were endocrine disorders (55 [11%] of patients in arm A vs 19 [7%] in arm D) and musculoskeletal disorders (30 [6%] of patients in arm A vs 15 [6%] in arm D). The independent data monitoring committee recommended stopping accrual to both celecoxib-containing arms on grounds of lack of benefit and discontinuing celecoxib for patients currently on treatment, which was endorsed by the trial steering committee.
INTERPRETATION:
Celecoxib 400 mg twice daily for up to 1 year is insufficiently active in patients starting hormone therapy for high-risk prostate cancer, and we do not recommend its use in this setting. Accrual continues seamlessly to the other research arms and follow-up of all arms will continue to assess effects on overall survival.
Resumo:
The purpose of this study was to compare the prostate-specific antigen (PSA) response to either neoadjuvant bicalutamide (BC) monotherapy or neoadjuvant luteinizing hormone-releasing hormone agonist (LHRHa) monotherapy and the subsequent effect on biochemical failure-free survival (BFFS) in men receiving radical radiotherapy (RT) for localized prostate cancer.
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It is likely that humans have sought enhancements for themselves or their children for as long as they have recognised that improvements in individuals are a possibility. One genre of self-improvement in modern society can be called 'biomedical enhancements'. These include drugs, surgery and other medical interventions aimed at improving the mind, body or performance. This paper uses the case of human growth hormone (hGH) to examine the social nature of enhancements. Synthetic hGH was developed in 1985 by the pharmaceutical industry and was approved by the FDA for very specific uses, particularly treatment of growth hormone deficiency. However, it has also been promoted for a number of 'off label' uses, most of which can be deemed enhancements. Drugs approved for one treatment pave the way for use as enhancements for other problems. Claims have been made for hGH as a treatment for idiopathic shortness, as an anti-ageing agent and to improve athletic performance. Using the hGH case, we are able to distinguish three faces of biomedical enhancement: normalisation, repair and performance edge. Given deeply ingrained social and individual goals in American society, the temptations of biomedical enhancements provide inducement for individuals and groups to modify their situation. We examine the temptations of enhancement in terms of issues such as unnaturalness, fairness, risk and permanence, and shifting social meanings. In our conclusions, we outline the potentials and pitfalls of biomedical enhancement.
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Little is known about the effects of clustered nursing care on hypothalamic pituitary axis (HPA) responses in preterm infants in the neonatal intensive care unit.
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GIP is a peptide hormone of therapeutic interest in type 2 diabetes and obesity. This study evaluated pGIP/neo STC-1 as a potential K-cell model for studying GIP secretion.
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The effects of changes in circulating gonadal steroids on GH secretion elicited by GHRH challenge (1µg/kg) in normal adults volunteers (aged 18-24 years), were evaluated in 10 women and 10 men before and after gonadal blockade was achieved by a GnRH agonist (1500 µg/day by nasal spray for 40 days). To see if the effect of testosterone on GH secretion was dependent on its aromatization to estradiol (E), GHRH tests were performed in 7 normal men prior to administration of testosterone enanthate (250 mg im), 8 days after this treatment had began, and again after E receptor blockade with tamoxifen (30 mg for 2 days plus 10 mg on the third day 2 h before the GHRH test, po) administered 8 days after testosterone enanthate. The study of the functional status of the somatotropes at the time of GHRH testing was made according to our previous postulate. Short-term gonadal blockade did not affect the parameters of GH response to GHRH in neither women nor men. Thus, the functional blockade of the gonads may be advisable as an adjunct therapy in the treatment of hypothalamic GH deficiency during the prepubertal stage. In the other group of men, administration of testosterone enanthate significantly increased GHRH-elicited GH release, but this was reverted after E receptor blockade. Since the hypothalamic-somatotrope rhythm was altered by both these farmacological manipulations, it appears that testosterone acts on GH release mainly at the suprapituitary level, and that this action is secondary to its aromatization to E.
Resumo:
The aim of this study was to gain further insight into the role that central dopaminergic pathways play in GH neuroregulation in man. Our experimental hypothesis was based on the possibility that most of the controversies on DA role could be due to the fact that the hypothalamic somatotroph rhythm (HSR) was not taken into account when interpreting the GH responses after pharmacological manipulations on dopaminergic pathways. In 10 normal subjects we monitored the effect of central dopaminergic blockade, achieved with metoclopramide (MCP; 10 mg, i.v. Bolus), on the pattern of spontaneous GH secretion and the GH responses to a GHRH challenge (GRF , 1 µg/kg, i.v. bolus) administered together with MCP or 60 min after this drug was given. The study of HSR was made according to our previous postulate. Our results indicate that MCP administration, either prior to or together with the GHRH bolus, significantly increased GHRH-induced GH release during a refractory HSR phase; but not when the GHRH challenge took place during a spotaneous secretory phase. The strong relationship between pre-GHRH plasma GH values and GHRH-elicited GH peaks was lost when MCP was given. These data indicate that MCP was able to disrupt the intrinsic HSR by inhibiting the hypothalamic release of somatostain (SS). While a main conclusion would be that central DA is a secretagogue for SS secretion, our results also suggest that this role could be dependent on its effects on the adrenergic inputs to SS neurons.
Resumo:
The aims of this study were: (1) to test the possibility that pre-GHRH plasma GH values could reflect the functional status of the hypothalamic-somatotroph rhythm (HSR) at testing, and thus explain if it is responsible for the marked variability in GH responsiveness to GHRH challenge and (2) to see if exogenous somatostatin (SS) could disrupt this endogenous HSR and thus make the GH responses homogeneous. (1) Two to 14 GHRH acute tests (GRF-29, 1 µg/kg, i.v. bolus) were performed in 12 normal men and 10 normal women at the same time (0830 h) at random intervals (2 to 60 days). Blood samples to measure plasma GH were drawn at 15 min intervals before and after GHRH challenge. Given that the increments in pre-GHRH plasma GH values (I = value at 0 min minus value at -15 min) were highly correlated with either GHRH-elicited peaks of GH (men, r = 0.81; women, r = 0.69; P