Does postnatal depression screening work? Throwing out the bathwater, keeping the baby

Background

Rates of help-seeking for Postnatal Depression (PND) are generally low and population screening has the potential to increase diagnosis rates. Of central importance is the screening instrument's Positive Predictive Value (PPV), which is itself influenced by the prevalence of the condition. When PPV exceeds prevalence, screening defines a screen-positive group with a higher prevalence to which diagnostic-stage procedures can be targeted, a necessary component of a screening program's potential for cost-effectiveness.

Methods

Employing the best available estimates of the prevalence of PND we applied Bayes’ Theorem to map the parameter space for the Positive Predictive Value of the Edinburgh Postnatal Depression Scale (EPDS) across a realistic range of values. Only seven methodologically comparable validation studies are available for major depression and/or minor depression.

Results

Screening with the EPDS always facilitated an increase in identification rates, over the key range of prevalence values. The EPDS defined a sub-group with prevalence between 5-fold and 17-fold greater than the general population. A central estimate of PPV (at a prevalence of 6.8%) was 62%.

Limitations

Few high-quality data are available for analysis and therefore better estimates, of both PND prevalence and of screening accuracy, in the populations where screening takes place are needed.

Conclusions

Our estimates of PPV indicate that population screening with an instrument at least as accurate as the EPDS could successfully increase the number of cases identified and, therefore, treatment rates. Comparisons with the performance of physical health-screening programs appear favourable. Appropriate training for health professionals is essential to minimize potential harms, and following all positive screening results with a formal diagnostic procedure is likely to be useful both clinically and in terms of health system costs.     

鲢鱼小清蛋白的分离纯化及其单克隆抗体的制备与鉴定

目的:制备抗鲢鱼主要过敏原小清蛋白的单克隆抗体,并对其基本特性进行鉴定。方法:采用硫酸铵盐析、离子交换柱层析和凝胶过滤柱层析等方法纯化鲢鱼小清蛋白;以纯化的小清蛋白免疫BALB/c小鼠,采用杂交瘤技术制备抗鲢鱼小清蛋白单克隆抗体;通过ELISA法确定抗体亚型;通过腹水诱生法大量制备单克隆抗体;以Protein G Sepharose亲和层析柱纯化制备的单克隆抗体;运用Western blot鉴定单克隆抗体的特异性;以ELISA法分析单克隆抗体的结合位点。结果:从100 g鲢鱼肌肉中可获得约30 mg高纯度小清蛋白;SDS-PAGE结果表明,得到的抗小清蛋白单克隆抗体(A4-C1)纯度较高,亚类为IgG1;Western blot结果显示,A4-C1只与鱼肉粗提物中的小清蛋白产生反应,特异性良好;ELISA分析表明,制备的抗鲢鱼小清蛋白单克隆抗体与商品化抗蛙小清蛋白单克隆抗体(PARV-19)的结合位点可能具有很大部分的重叠,或者存在较大的空间位阻效应。结论:研究中制备的杂交瘤细胞株能稳定分泌高特异性的抗鲢鱼小清蛋白单克隆抗体,可用于后续淡水鱼类小清蛋白检测方法的建立。     

Posterior pelvic pain provocation test is negative in patients with lumbar herniated discs

The classification of pelvic girdle pain can only be reached after lumbar causes have been excluded by a clinical examination. During clinical examination, the posterior pelvic pain provocation test is a well-established method for verifying pelvic girdle pain. However, a criticism of pelvic pain provocation tests is that they may have an effect on lumbar structures, thus yielding false-positive results. The posterior pelvic pain provocation test was performed with four groups of patients: patients with computed tomography-verified disc herniations (1) on the waiting list for surgery (14 women; 9 men); (2) 6 weeks after disc surgery (18 women, 12 men); (3) pregnant women seeking care for pelvic girdle pain (n = 25); and (4) women with persistent pelvic girdle pain after delivery (n = 32). The sensitivity of the posterior pelvic pain provocation test was 0.88 and the specificity was 0.89. The positive predictive value was 0.89 and the negative predictive value was 0.87. Analysis of only women showed similar results. In our study, the posterior pelvic pain provocation test was negative in patients with a well-defined lumbar diagnosis of lumbar disc herniation, both before and after disc surgery. Our results are an important step toward the more accurate classification of lumbopelvic pain.     

B病毒糖蛋白的原核表达及ELISA检测方法的建立

目的表达B病毒糖蛋白,筛选出具有较好检测敏感性和特异性的抗原或抗原组合,用以检测猴血清中的抗体。方法原核表达B病毒糖蛋白C,D和G,经纯化、复性后用蛋白印记验证其抗原性,建立ELISA法,对方法进行评价。结果3个表达抗原反应特异性较好;以BV-ELISA为标准,各抗原的检测敏感性分别是：BVgC-ELISA84.6％,BVgD-ELISA88.5％,BVgC＋gD-ELISA96.2％,检测特异性分别是：BVgC-ELISA93％,BVgD-ELISA85.7％,BVgC＋gD-ELISA64.3％。结论表达的3个BV重组抗原都具备作为替代抗原检测BV抗体的潜力。     

常规生化指标评估慢性肝功能损害的临床应用价值

目前国内用于诊断慢性肝功能损害的血清学检测指标很多，但对其诊断效率进行客观评价的研究并不多。目的：采用受试者工作特征曲线（ROC曲线）和诊断性能指标对常用的7项血清学指标进行综合分析，探讨其临床应用价值。方法：检测肝硬化组（n=81）、慢性肝病组（n=43）和健康对照组（n=30）的血清白蛋白（ALB）、丙氨酸氨基转移酶（ALT）、天冬氨酸氨基转移酶（AST）、乳酸脱氢酶（LDH）、腺苷脱氨酶（ADA）、5’-核苷酸酶（5’-NT）、胆碱酯酶（ChE）等7个生化指标，应用ROC曲线进行分析，评价各指标的敏感性和特异性，观察不同肝病组上述指标的变化情况。结果：与慢性肝病组和健康对照组相比，肝硬化组ALB、ChE显著下降，AST显著升高（P〈0．05）；ROC曲线下面积ALB最高，ChE次之。7项指标中ChE的敏感性和特异性最高，分别为93．8％和83．7％；诊断准确率ChE最高，达90．3％，ALB次之，为89．5％。结论：临床常规的7项生化指标中，ALB和ChE最能反映肝硬化特别是肝硬化失代偿期肝功能损害程度。     

Phagocytosis mediates specificity in the immune defence of an invertebrate, the woodlouse Porcellio scaber (Crustacea: Isopoda)

Specificity and memory are the hallmarks of the adaptive immune system of vertebrates. However, phenomena of specificity upon priming of immunity have recently been demonstrated also in invertebrates, which rely exclusively on innate immune defence. It has been suggested that phagocytosis might represent a core candidate for such specificity in invertebrates. We here developed in vitro phagocytosis measurements for different bacteria in the woodlouse Porcellio scaber (Crustacea: Isopoda). After immune priming with heat-killed bacteria, hemocytes showed increased phagocytosis of a previously encountered bacterial strain compared to other bacteria. These data support the role of phagocytosis in invertebrate immunological specificity and suggest a high degree of specificity that even enables to differentiate between strains of the same bacterial species.     

同型半胱氨酸在肝脏疾病中的诊断价值

目的探索同型半胱氨酸（Hcy）在肝脏疾病中的诊断价值。方法观察37例乙型肝炎患者,29例肝硬化患者,45例原发性肝细胞癌患者以及35例正常对照组血清中丙氨酸氨基转移酶,天冬氨酸氨基转移酶,白蛋白,总胆汁酸,总胆红素和同型半胱氨酸水平的差异,分析同型半胱氨酸用于诊断原发性肝癌的灵敏性和特异性。结果各项生化指标与对照组相比,乙肝组白蛋白、总胆汁酸和同型半胱氨酸以及肝硬化组Hcy差异无统计学意义（P〉0.05）,其余差异均有统计学意义（P〈0.05）;同型半胱氨酸水平与天冬氨酸氨基转移酶和总胆红素呈正相关;同型半胱氨酸用于原发性肝细胞癌诊断时,ROC曲线下面积为A=0.70,且当其临界值取0.14时诊断敏感性为62.2%、特异性为94.3%。结论同型半胱氨酸可作为反映肝脏疾病的生化指标之一,且对原发性肝细胞癌具有一定的诊断价值。