5alpha-dihydrotestosterone inhibits 1alpha,25-dihydroxyvitamin D3-induced expression of CYP24 in human prostate cancer cells

BACKGROUND: A cross-talk between 1alpha,25-dihydroxyvitamin D(3) [1alpha,25-(OH)(2)D(3)] and 5alpha-dihydrotestosterone (DHT) in the growth inhibition has been demonstrated, but the mechanism is unknown. METHODS: The expression of 25-hydroxyvitamin D(3) 24-hydroxylase (24-hydroxylase) was measured using a real-time quantitative RT-PCR assay and the catabolism of 1alpha,25-(OH)(2)D(3) was measured using a radioreceptor assay. RESULTS: Real-time RT-PCR showed that DHT at 1-100 nM significantly inhibited 1alpha,25-(OH)(2)D(3)-induced expression of 24-hydroxylase in LNCaP cells. Furthermore, the catabolism of 1alpha,25-(OH)(2)D(3) was decreased by 10 nM DHT. An androgen receptor (AR) antagonist, Casodex antagonized the DHT effect, whereas an AR agonist (due to the mutant AR in LNCaP cells) hydroxyflutamide did not. CONCLUSIONS: We demonstrated, for the first time, that DHT reduces the ability of 1alpha,25-(OH)(2)D(3) to induce 24-hydroxylase expression. Our results not only support the earlier finding of a cross-talk between androgen and vitamin D in human prostate cancer cells but also provide a possible mechanism how androgen and vitamin D signaling pathways may interact.     

Meeting the Challenge of Managed Care Through Clinical Pathways for Bariatric Surgery

Background: The 1990s will bring sweeping changes in managed care and capitation. Health care providers are continually searching for new ways to improve the quality of patient-care outcomes in the obese. Improving clinical care by promoting the use of processes that have been proved to yield optimal outcomes has become a powerful strategy for measuring the value of services provided. Methods: To address this cost/quality paradox, an optimal care path (OCP) was developed as a guideline for all patients undergoing gastric bypass or laparoscopic adjustable gastric banding. A transdisciplinary team developed the OCP, preprinted orders, discharge home instruction sheet, and daily guidelines for patients. All patients were provided with OCPs from July 1995 to September 1997. Results: Length of stay decreased from 6.5 days to 5.4 days (16.9%); the average total charges decreased 17.6%, or $2,683; the percentage of wound infections decreased; and communication between, and collaboration of, interdisciplinary team members increased across the continuum of care. Conclusions: The study suggests that the use of OCP does not impair quality of care and can produce significant cost savings to a health care facility.     

圆柱型Halbach永磁魔环研究进展

受局部饱和和局部退磁效应的影响以及磁材料性能的限制,永磁体的气隙磁场一般难以达到4T。Halbach永磁魔环结构磁材料利用效率高,且能够产生比剩磁更高的静磁场,因而近年来在磁共振成像领域得到了广泛关注。本文针对Halbach永磁魔环的构成形式,介绍了永磁魔环、阵列永磁魔环、永磁双魔环和单边永磁魔环的研究现状,分析了这些魔环结构由于永磁磁块形状、尺寸,永磁材料受温度变化影响,和加工工艺等因素引起的磁场均匀性较差等主要问题,并对圆柱型Halbach永磁魔环在NMR、MRI和便携式分析仪器等方面的应用进行了展望。     

青蒿琥酯治疗晚期视网膜母细胞瘤的临床疗效与安全性

 目的 探讨青蒿琥酯治疗晚期视网膜母细胞瘤(retinoblastoma, RB)的临床疗效与安全性。方法 总结武警总医院儿科自2012-10至2014-01采用青蒿琥酯联合常规方案(联合治疗组)治疗晚期RB11例患儿的临床资料,并与同期采用常规方案(对照组)治疗的11例晚期RB患儿进行比较,分析总结青蒿琥酯治疗晚期RB的临床疗效及安全性。结果 (1)联合治疗组中4例眼内D、E期患儿中有2例成功保留眼球(50%),5例眼外期患儿中有2例获得手术机会(40%);对照组中7例眼内D、E期的患儿中仅有2例获得保眼机会(28.6%),3例眼外期患儿中有1例获得手术机会(33.3%)。两组间差异均无统计学意义(均P>0.05);(2)截至2015-02-01,联合治疗组的中位无进展生存期(progression-free survival, PFS)和中位总生存期(overall survival, OS)分别为18.2个月和21.8个月,对照组的中位PFS和中位OS分别为18.4个月和21个月,两组间比较差异无统计学意义;(3)所有患儿在给予青蒿琥酯期间均未发生过敏反应,生命体征平稳。两组不良反应的发生率无统计学差异。结论 青蒿琥酯治疗晚期视网膜母细胞瘤有一定疗效,安全性良好。     

Effects of low‐frequency pulsed electromagnetic fields on plateau frostbite healing in rats

Plateau frostbite (PF) treatments have remained a clinical challenge because this condition injures tissues in deep layers and affected tissues exhibit unique pathological characteristics. For instance, low‐frequency pulsed electromagnetic field (PEMF) can affect tissue restoration and penetrate tissues. Therefore, the effect of PEMF on PF healing should be investigated. This study aimed to evaluate the effects of low‐frequency PEMF on PF healing systematically. Ninety‐six Sprague‐Dawley rats were randomly and equally divided into three groups: normal control, partial thickness plateau frostbite (PTPF), and PTPF with low‐frequency PEMF exposure (PTPF + PEMF). PTPF wounds were induced in the dorsum of the rats. The PTPF + PEMF group was exposed to low‐frequency PEMF daily. During PF healing, wound microcirculation in each group was monitored through contrast ultrasonography. Wound appearance, histological observation, and wound tensile strength were also evaluated. Results showed that the rate of the microcirculation restoration of the PTPF + PEMF group was nearly 25% faster than that of the PTPF group, and wound appearance suggested that the healing of the PTPF group was slower than that of the PTPF + PEMF group. Histological observation revealed that PEMF accelerated the growth of different deep tissues, as confirmed by tensile strength examination. Low‐frequency PEMF could penetrate PF tissues, promote their restoration, and provide a beneficial effect on PF healing. Therefore, this technique may be a potential alternative to treat PF.     

Association of psychological and physiological measures of stress in health‐care professionals during an 8‐week mindfulness meditation program: mindfulness in practice

Work stress, burnout, and diminished empathy are prevalent issues for health‐care professionals. Mindfulness meditation (MM) is one commonly used strategy to manage stress. Measuring salivary cortisol allows for the assessment of serum cortisol level, a known stress level indicator. This study evaluated the association of subject‐reported stress symptoms and salivary cortisol in health‐care professionals, in an 8‐week MM program, with data collected prospectively at baseline and 8 weeks after program completion. Questionnaires [Profile of Mood States—Short Form (POMS‐SF), Maslach Burnout Inventory (MBI), and Interpersonal Reactivity Index (IRI)] measured mood, burnout and empathy. A paired t‐test between groups for pre/post‐salivary cortisol yielded no significant change. The POMS‐SF was most sensitive to change (mean increase 12.4; p = 0.020). Emotional exhaustion, measured in the MBI, was also affected by MM (mean decrease 4.54; p = 0.001). Changes in empathy may not have been captured due to either absence of effect of MM on empathy, subject number or scale sensitivity. Baseline and 8‐week correlations between salivary cortisol and survey results, and correlations between changes in these measures, were weak and not statistically significant. Nevertheless, psychometric results present a strong case for additional clinical trials of MM to reduce stress for health‐care professionals. Copyright © 2005 John Wiley & Sons, Ltd.     

1周跑台运动对脑缺血再灌注大鼠海马BDNF、VEGF和KDR mRNA表达的影响

目的:探讨跑台运动对脑缺血再灌注大鼠海马脑源性神经营养因子(BDNF)、血管内皮生长因子(VEGF)和VEGF受体KDR mRNA表达的影响。方法:使用可逆性阻塞大脑中动脉的方法建立大鼠单侧脑缺血再灌注模型,将符合模型条件的16只大鼠随机分为对照组和运动组,运动方式采取小强度跑台运动,为期1周。另选取8只大鼠作为假手术组。实验后采用实时荧光定量PCR方法测定大鼠海马组织中BDNF、VEGF及KDR mRNA表达。结果:(1)对照组和运动组大鼠缺血侧海马BDNF mRNA表达量显著高于非缺血侧。运动组大鼠缺血侧海马BDNF mRNA表达量显著高于对照组。(2)对照组大鼠海马缺血侧VEGF mRNA表达量显著高于非缺血侧。运动组大鼠两侧海马VEGF mRNA水平分别显著高于对照组。(3)对照组和运动组大鼠缺血侧海马KDR mRNA表达量显著高于非缺血侧。运动组大鼠缺血侧海马KDR mRNA水平显著高于对照组。结论:跑台运动可明显提高缺血再灌注大鼠海马部位BDNF、VEGF及KDR mRNA水平。     

隔室推药子宫输卵管造影的临床应用

目的探讨隔室手推造影剂子宫输卵管造影的应用价值。方法将12F硅胶球囊导管插入子宫腔，注入2-3mL生理盐水充盈球囊，使球囊堵塞子宫颈内口。延长管与球囊导管和注射器相接，用适当的压力推注造影剂，在电视监视下，确定导管位置良好且嵌塞后，逐渐加压，在子宫腔输卵管逐步充盈时，实时摄片。遇输卵管阻塞时，加压推注，能使轻度粘连阻塞的输卵管再通，发现逆流立即停止推药。结果本组检查2300例，一次造影成功2116例（92％）；二次造影成功115例（5％）；改用子宫颈塞法手推造影69例（3％）。造影示子宫输卵管正常483例（2l％），子宫病变207例（9％），输卵管病变1610例（70％），其中，463例（28．7％）阻塞的输卵管再通。患者无须在放射科插管，医师、患者受照辐射量少，推注压力能灵活调节，未出现严重的并发症。结论该法简便、经济实用、安全、推注压力可调节，图像清晰、隔室推药，辐射剂量小，对轻度粘连阻塞的输卵管有再通作用，值得推广应用。