Métodos para cuantificar la testosterona sérica en pacientes con cáncer de próstata sometidos a castración: una revisión sistemática

Background

The clinical practice guidelines recommend measuring serum testosterone in patients with prostate cancer (PC) who undergo castration. The serum testosterone concentration should be <50 ng/dL, a level established by using a radioimmunoassay method. The use of chemiluminescent immunoassays (IA) has become widespread, although their metrological characteristics do not seem appropriate for quantifying low testosterone concentrations. The objective of this review is to analyse the methods for quantifying testosterone and to establish whether there is scientific evidence that justifies measuring it in patients with PC who undergo castration, through liquid chromatography attached to a mass spectrometry in tandem (LC-MSMS).

Evaluation of the penetration of nanocrystalline silver through various wound dressing mediums: An in vitro study

Background

The nanocrystalline silver (NCS) dressing Acticoat is commonly used in clinical practice for the treatment of burns and other open wounds as a topical antimicrobial. The dressing may dry resulting in traumatic dressing changes; hence the variety of contact layer dressings used in conjunction with it. Dressing combinations that do not permit NCS penetration are not cost effective and deprives the wound of the needed anti-microbial.

高效液相色谱法测定家兔离体血液中头孢哌酮衰除速度的实验研究

目的比较家兔体内与体外头孢哌酮衰除速度的差异,了解离体血液中头孢哌酮对受血者的影响。方法健康家兔20只,体重(3±0.3)kg,随机分为实验组(离体组)和(在体组)各10只,2组均从兔耳缘静脉注射头孢哌酮150mg/kg,实验组于给药45min后从耳缘静脉取血(8—10)ml/只,置于(4±2)℃冰箱保存,用高效液相色谱法测定0、6、12、24、48、72、120和168h血药浓度;对照组分别于给药后1、2、3、4、5h从耳缘静脉取血1ml/只(次),用高效液相色谱法测定血药浓度;分别计算兔离体和在体血液中头孢哌酮的半衰期。结果实验组血液中头孢哌酮的消除半衰期为(146.08±9.56)h,对照组则为(1.55±0.048)h。离体血液中头孢哌酮的半衰期较在体血液中头孢哌酮的半衰期显著延长(P<0.01)。结论离体血液中头孢哌酮代谢较慢,不能在血液储存期内衰除到安全浓度水平以下,输血时可能引起受血者产生药物不良反应。     

24h食管pH监测和食管测压及奥美拉唑治疗试验在食管原性胸痛中的应用

目的 :探讨 2 4 h食管 p H监测和食管测压及奥美拉唑治疗试验在食管原性胸痛中的诊断价值。方法 :对食管原性胸痛 6 8例行内镜、食管测压、2 4 h食管 p H监测及 7d的奥美拉唑 (2 0 mg,2次 / d)治疗试验 ,治疗后症状评分比治疗前降低超过 75 %者则为治疗试验阳性。结果 :食管原性胸痛 6 8例中 5 5例 (81% )符合胃食管反流病 (GERD) ,胡桃夹食管 2例 ,早期贲门失驰缓症 3例 ,弥漫性食管痉挛 3例 ,无效食管运动 (IEM) 5例。GERD5 2例测压分析 ,35例(6 7% )符合 IEM诊断标准。奥美拉唑治疗试验对诊断 GERD的敏感性为 93% ,特异性为 85 %。结论 :GERD是食管原性胸痛的主要原因。 2 4 h食管 p H监测和食管测压是诊断食管原性胸痛的主要检查手段 ,奥美拉唑治疗试验是临床诊断GERD简便而实用的方法。     

A fatal case of Exophiala dermatitidis meningoencephalitis in an immunocompetent host: A case report and literature review

BackgroundCentral nervous system (CNS) infection due to Exophiala dermatitidis is rare and fatal, and primarily reported in immunocompromised patients or those with caspase recruitment domain-containing protein 9 deficiency. Herein, we describe a case of an otherwise healthy person (without underlying disease or gene deficiency) diagnosed with Exophiala dermatitidis meningoencephalitis. The patient achieved clinical remission under high-dose antifungal therapy in the first 14 months but died after 2 years of the therapy.Case presentationA 15-year-old student with headache and fever was admitted to our department. Lumbar puncture showed increased cerebrospinal fluid (CSF) pressure, moderately high CSF protein levels and cell counts, and a remarkable decrease in CSF glucose and chloride. Magnetic resonance imaging of the brain revealed multiple lesions and cerebral pia mater enhancement. CSF culture confirmed E. dermatitidis infection. We administered 4-week antifungal therapy of amphotericin B, but his CSF culture remained positive. After receiving the 12-week standard dose of voriconazole (200 mg q12h), the patient's CSF culture became negative, but his condition deteriorated with intracranial lesion enlargement. We administered a high-dose voriconazole therapy (600–800 mg per day) for 12 months, which led to clinical remission. The voriconazole dose was reduced due to adverse effects including hepatic dysfunction and hypokalemia, and the disease progressed with high intracranial pressure and epileptic seizures.ConclusionsCNS infection caused by E. dermatitidis is fatal and the most serious form of fungal infection. Initially, high-dose and long-term antifungal therapy could be effective. Gene defect and related antifungal immunodeficiency may be the most important pathogenic and lethal factor.     

多通道微流控芯片的设计、仿真及细胞迁移应用研究

细胞迁移是指细胞朝着特定的化学浓度梯度发生定向迁移运动,其在胚胎发育、伤口愈合、肿瘤转移中发挥着至关重要的作用。当前研究手段大多通量低,难以综合考虑不同浓度梯度条件对细胞迁移行为的影响。针对上述问题,本文首先设计了一款四通道微流控芯片,其特征如下:借助层流和扩散机制在细胞迁移主通道中建立和维持浓度梯度;可在单一显微镜视野下同时观测四组细胞迁移现象;集成了宽度为20μm的细胞隔离带,可校准细胞初始位置,保证实验结果的准确性。随后,借助Comsol Multiphysics有限元分析软件完成了微流控芯片的仿真分析,证明了芯片上设计S型微通道和水平压力平衡通道有助于在细胞迁移主通道中形成稳定的浓度梯度。最后,采用不同浓度(0、0.2、0.5、1.0μmol·L^-1)与糖尿病及其并发症密切相关的晚期糖基化终末产物(AGEs)孵育中性粒细胞,研究了其在100 nmol·L^-1趋化因子fMLP浓度梯度环境中的迁移行为。结果表明,AGEs抑制了中性粒细胞的迁移能力,证明了四通道微流控芯片的可靠性和实用性。     

Taurocholate-stimulated leukotriene C4 biosynthesis and leukotriene C4-stimulated choleresis in isolated rat liver

Cysteinyl-containing leukotrienes seem to exert a cholestatic effect. However, leukotriene inhibitors were found to reduce bile salt efflux in isolated rat hepatocytes, suggesting a role for leukotrienes in bile flow formation. In the isolated rat liver, the effects of two different concentrations of leukotriene C₄ on bile flow and bile salt excretion are analyzed, as well as the possible effect of taurocholate on the hepatic production of cysteinyl-containing leukotrienes. Leukotriene C₄ (0.25 fmol) increased bile salt excretion (+22.2%; P < 0.05), whereas a much higher dose (0.25 × 10⁶ fmol) showed the known cholestatic effect, reducing bile salt excretion (−25.9%; P < 0.01). These dose-dependent biphasic effects were specific because they could be prevented by the simultaneous administration of cysteinyl-containing leukotriene antagonists. On the other hand, taurocholate administration induced a dose-dependent increase in biliary excretion of cysteinyl-containing leukotrienes. Furthermore, taurocholate increased messenger RNA levels of 5-lipoxygenase, a key enzyme in leukotriene biosynthesis. Taurocholate increase of hepatocyte intracellular calcium was not significant, suggesting that taurocholate effects are not mediated by stimulation of calcium metabolism. These results constitute evidence for the existence of a positive feedback mechanism by which bile salts stimulate the synthesis of leukotrienes that, in turn, stimulate bile salt excretion.     

Acute changes in plasma non-esterified fatty acid concentration do not change hepatic glucose production in people with type 2 diabetes

The effect of changes in plasma non-esterified fatty acid concentration (NEFA) on plasma glucose concentration, hepatic glucose production (Ra), and glucose disposal (Rd) rates was determined in 14 patients with Type 2 diabetes. Seven patients had relatively mild fasting hyperglycaemia (less than 10.0 mmol l-1), whereas the remaining seven had relatively severe fasting hyperglycaemia (greater than 14.0 mmol l-1). Each patient was infused from 2000 to 0800 h with 3-3H-glucose on two occasions, with or without neutral fat emulsion and heparin (mild hyperglycaemia group), or with or without nicotinic acid (severe hyperglycaemia group). Plasma NEFA concentration increased from 0.33 +/- 0.06 (+/- SE) to 4.78 +/- 0.42 mmol l-1 in response to the lipid and heparin infusion, but plasma glucose concentration (7.8 +/- 0.7 vs 7.4 +/- 0.8 mmol l-1), Ra (0.44 +/- 0.02 vs 0.46 +/- 0.02 mmol m-2 min-1), and Rd (0.42 +/- 0.02 vs 0.46 +/- 0.02 mmol m-2 min-1) were unchanged. Nicotinic acid decreased plasma NEFA concentration from 0.54 +/- 0.15 to 0.23 +/- 0.08 mmol l-1, but plasma glucose (15.0 +/- 1.0 vs 15.5 +/- 1.4 mmol l-1), Ra (0.74 +/- 0.07 vs 0.68 +/- 0.07 mmol m-2 min-1), and Rd (0.73 +/- 0.07 vs 0.68 +/- 0.07 mmol m-2 min-1) were unchanged. The results indicate that acute changes in plasma NEFA concentration did not lead to any change in overnight glucose production or disposal rates.     

Socio‐economic inequality in health service utilisation: Does accounting for seasonality in health‐seeking behaviour matter?

Seasonal variation exists in disease incidence. The variation could occur across the different regions in a country. This paper argues that using national household data that are not adjusted for seasonal and regional variations in disease incidence may not be directly suitable for assessing socio‐economic inequality in annual outpatient service utilisation, including for cross‐country comparison. In fact, annual health service utilisation may be understated or overstated depending on the period of data collection. This may lead to miss‐estimation of socio‐economic inequality in health service utilisation depending, among other things, on how health service utilisation, across geographical areas, varies by socio‐economic status. Using a nationally representative dataset from South Africa, the paper applies a seasonality index that is constructed from the District Health Information System, an administrative dataset, to annualise public outpatient health service visits. Using the concentration index, socio‐economic inequality in health service visits, after accounting for seasonal variations, was compared with that when seasonal variations are ignored. It was found that, in some cases, socio‐economic inequality in outpatient health service visits depends on the socio‐economic distribution of the seasonality index. This may justify the need to account for seasonal and geographical variations.