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81.
PURPOSE: Adrenal androgens activate the androgen receptor and stimulate prostate cancer growth. Ketoconazole is used as an inhibitor of adrenal androgen synthesis in men with androgen-independent prostate cancer. This study analyzes the relationship between pretreatment androgen levels and outcome following ketoconazole treatment. EXPERIMENTAL DESIGN: Baseline levels of three adrenal androgens (androstenedione, dehydroepiandrostenedione, and dehydroepiandrostenedione-sulfate) and testosterone were measured. Regression models (logistic and proportional hazard) were used to assess the prognostic significance of these levels in predicting overall survival and prostate-specific antigen (PSA) response defined by Consensus Criteria. RESULTS: In 103 patients with available levels, PSA response rate was 28% and median response duration was 4.8 months. The median baseline androstenedione level was 0.64 ng/mL and was 0.88 ng/mL versus 0.53 ng/mL for those with and without a PSA response, respectively (P = 0.034). In univariate analysis, elevation of baseline androstenedione levels was predictive of PSA response [odds ratio, 2.26; 95% confidence interval (95% CI), 1.03-4.96; P = 0.043]. In multivariate analysis, both the uppermost and the middle tertile of baseline androstenedione level were associated with an improved overall survival compared with those in the lower tertile (hazard ratio, 0.59; 95% CI, 0.36-0.98; P = 0.40; hazard ratio, 0.53; 95% CI, 0.32-0.90; P = 0.018, respectively). A linear correlation was observed among all androgen levels. CONCLUSIONS: Higher androstenedione levels predict likelihood of response to ketoconazole and improved survival compared with patients with lower levels. These data suggest that therapy with ketoconazole is less effective in patients with low levels of androgen at baseline.  相似文献   
82.
We describe a young man who developed extensive hypothalamicdysfunction including diabetes insipidus, adipsia, hyperprolactinaemia,and poikiliothermia together with central sleep apnoea followingexposure to toluene.  相似文献   
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Herbs and botanicals are used by a large number of people in the United States and have been used therapeutically in Europe for decades. Consumers are becoming more interested and subsequently better informed on the use of herbs to self-treat minor illness. Unfortunately, because of conflicting and anecdotal information, variable potency, and the widespread availability of herbs, many home care patients are left vulnerable to potentially life-threatening situations. A neutral discussion of alternative medical treatment should occur with all home care patients. Carefully worded questions should be asked and documented in the medical record. Finally, science-based teaching tools outlining the risks and benefits of botanicals must be available. A registered dietitian or pharmacist should be able to help nurses and agencies locate appropriate teaching tools on dietary supplements, including commonly used herbs and meal replacements.  相似文献   
86.
The in vitro and in vivo effects of cryopreservation on the cytotoxic activity of murine lymphokine-activated killer (LAK) cells were studied. LAK cells were generated by incubation of spleen lymphocytes of BALB/c mice for 3 days with recombinant interleukin-2 (rIL-2) and subsequent cryopreservation. Cytotoxicity was determined in a 51Cr release assay. After thawing, cytotoxic activity was reduced (40.4% 51Cr release at an effector:target cell ratio of 40:1 as compared to 68.5% 51Cr release before freezing) and could be restored to precryopreserved levels by reincubation with rIL-2 for 2 days after thawing (78.8% 51Cr release). These cells were then tested in BALB/c mice injected with RAW 112 cells, a pre-B-cell lymphoma line. The results demonstrate that the survival rate of mice injected with cryopreserved and restimulated LAK cells (50% survival greater than 180 days after injection) did not differ significantly from that of mice injected with fresh unfrozen LAK cells (60% survival greater than 120 days, 50% survival greater than 180 days). Cryopreserved LAK cells have potential use in adoptive immunotherapy.  相似文献   
87.

INTRODUCTION

Patient-directed information available on the internet is not always regulated; it may be confusing and sometimes just overwhelming. We aimed to establish the proportion of patients undergoing two common surgical procedures, who searched the internet for information about their operations and to assess the usefulness of the information they received.

PATIENTS AND METHODS

A total of 105 consecutive patients undergoing elective abdominal wall hernia repair (n = 54) or laparoscopic cholecystectomy (n = 51) in a single surgical firm were included in the study. Patients were counselled about their operation in pre-operative assessment clinics and standard trust information leaflets were provided without any mention of this study. Patients were then asked to complete a questionnaire on the morning of their operation.

RESULTS

All patients completed the questionnaire. Of the patients, 59% stated that they had access to the internet and 77% of these accessed the internet over 2 h a week. Of the patients with internet access, 31% used it to acquire additional information about their operations and 58% used internet search engines. Of the patients who searched the internet regarding their operations, 26% were confused and/or worried by the information they received.

CONCLUSIONS

A significant proportion of patients undergoing common surgical procedures used the internet and about one-third of them specifically sought information about their operation on the internet. Such information can cause worry and confusion in patients. Our study highlights the need for regulated, comprehensible, patient information on hospital websites to which patients should be directed.  相似文献   
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89.

Introduction

Circulating tumor cell (CTC) enumeration by using the Cellsearch platform has established prognostic and predictive value in patients with metastatic castration-resistant prostate cancer (mCRPC). Limited information exists regarding the clinical utility of CTC enumeration in metastatic hormone-sensitive prostate cancer (mHSPC). The goal of this study was to prospectively determine the relative clinical utility of CTCs in mHSPC.

Patients and Methods

We analyzed serial CTC in conjunction with other classic biomarkers in 33 consecutive patients treated at the Nevada Cancer Institute with HSPC initiating androgen deprivation therapy and correlated these patients with prognostic prostate-specific antigen (PSA) endpoints and onset of CRPC.

Results

Initial CTC correlated positively with lactate dehydrogenase and alkaline phosphatase, and were unrelated to PSA and testosterone. In univariate analysis, baseline CTC, alkaline phosphatase, lactate dehydrogenase, testosterone, and follow-up CTC were individual predictors of progression to CRPC. In a multivariate Cox regression, only baseline CTC retained independent predictive value. Threshold analysis revealed the cutpoint that optimized specificity and sensitivity of the test to be 3 cells per 7.5 mL whole blood. Baseline CTC also correlated well with PSA nadir benchmarks.

Conclusions

Initial CTC values predict the duration and magnitude of response to hormonal therapy. CTC enumeration may identify patients at risk of progression to CRPC before initiation of androgen deprivation therapy.  相似文献   
90.

Background and purpose:

The function of transporters in peripheral blood mononuclear cells (PBMC) has been characterized, but less is known about cytochrome P450 (CYP) enzyme function in these cells. Given that cytokines are dysregulated in many diseases, the purpose of this work was to assess the impact of cytokines on the expression of CYPs, transporters and chemokine receptors in PBMC.

Experimental approach:

Human PBMC were incubated with cytokines for 48 h. ATP-binding cassette (ABC)B1, ABCC1, ABCC2, CYP2B6, CYP3A4, CXCR4 and CCR5 expression were measured by quantitative polymerase chain reaction and flow cytometry at 0, 4, 8, 24 and 48 h. Enzyme activity was assessed using fluorescent probes.

Key results:

We show here functional activity of CYP3A4 and CYP2B6 in PBMC. Furthermore, cytokines had a significant impact on the mRNA and protein expression of all proteins. For example, interleukin-2 (IL-2) had a marked impact on ABCB1 mRNA (% control 4745 ± 11961) and protein (% control 200 ± 57). Increases in drug efflux transporter expression, in response to cytokines, resulted in reduced cellular accumulation of digoxin [decrease of 17% and 26% for IL-2 and interferon-γ (IFNγ) respectively] and saquinavir (decrease of 28% and 30% for IL-2 and IFNγ respectively). The degree to which drug transporter and chemokine receptor expression changed in response to cytokines was positively correlated (e.g. ABCB1 and CXCR4, r2 = 0.545).

Conclusions and implications:

These data have important implications for diseases in which cytokines are dysregulated and for which pharmacological intervention targets immune cells.  相似文献   
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