Clinically-based determination of safe DNAemia cutoff levels for preemptive therapy or human cytomegalovirus infections in solid organ and hematopoietic stem cell transplant recipients

Transplantation Centers using human cytomegalovirus (HCMV) antigenemia-based preemptive therapy will need to replace in the near future the antigenemia assay with a more standardized and automatable assay, such as a molecular assay quantifying HCMV DNA in blood (DNAemia). Thus, in view of replacing antigenemia with clinically safe cutoff values, DNAemia levels corresponding to antigenemia cutoffs guiding HCMV preemptive therapy were determined retrospectively in solid organ and hematopoietic stem cell transplant recipients (HSCTR) using an "in-house" quantitative PCR (QPCR) method. Since preemptive therapy had prevented appearance of HCMV disease in all patients tested, DNA cutoffs determined retrospectively had to be considered as safe clinically as antigenemia cutoffs used prospectively. However, in solid organ transplant recipients (SOTR), initiating preemptive therapy upon an antigenemia cutoff of 100 pp65-positive leukocytes, a DNAemia cutoff of 300,000 copies/ml blood had positive and negative predictive values of >90%, indicating that a DNAemia cutoff could achieve, in terms of prevention of HCMV disease, the same clinical results as the antigenemia cutoff. In HSCTR, initiating preemptive therapy upon first antigenemia positivity, a DNAemia cutoff of 10,000 copies/ml blood had a positive predictive value of >90%, indicating that the great majority of patients treated under the antigenemia guidance would have been treated also using this DNA cutoff. On the other hand, the negative predictive value of 28.6% indicated that two out of three HSCTR had been treated under the antigenemia guidance having the same levels of viral DNA as the untreated patients. The data suggest that a quantitative cutoff could be adopted as a guiding criterion for preemptive therapy also in HSCTR. Regression analysis allowed to determine the DNAemia (corresponding to QPCR) cutoff values for two commercial assays tested both in solid organ and HSCTR. Retrospective DNAemia cutoff values will be verified for safety in prospective trials.     

任务的呈现方式对孤独症儿童误念理解的影响

目的:探讨一种更适于测试孤独症儿童误念理解能力的方法.方法:2(呈现方式)×2(被试类型)设计,采用经典误念任务,使用计算机多媒体动画呈现方式与传统图片-实物呈现方式,分别测试20名孤独症儿童和言语能力(PPVT-R)匹配的正常儿童.结果:呈现方式的主效应非常显著(P<0.001),动画呈现方式使正常儿童和孤独症儿童的误念理解成绩都有提高,孤独症儿童的提高更大.结论:孤独症儿童的误念理解能力在误念任务的传统呈现方式之下可能被低估了.充分考虑孤独症认知缺陷的多样性,使用恰当的任务方式,可能会更真实地反映他们的心理理论发展水平.     

社会技能训练对慢性精神分裂症疗效的对照研究

目的:探讨社会技能训练对慢性精神分裂症阳性症状、阴性症状及认知功能的疗效.方法:将100例慢性精神分裂症患者随机分为训练组(50例)和对照组(50例).对训练组按照Liberman RP编写的<社会独立生活技能>训练程式进行训练,共12周.用BPRS、SANS、SDSI和WCST进行评定.结果:(1)训练组BPRS在总分和焦虑抑郁及缺乏活力因子分低于对照组,差异有显著性(P<0.05).(2)接受12周社交技能训练后,训练组的SANS量表全部五个因子和总分低于对照组,均有显著差异(P<0.05).(3)训练组和对照组在WCST的5个指标,差异有显著性(P<0.05).(4)SDSI评定结果表明,训练后明显降低,差异有显著性(P<0.05).结论:社会技能训练能够改善慢性精神分裂症的阳性症状、阴性症状及认知功能.     

Infrared spectroscopy: A new diagnostic tool in Alzheimer disease

Biological markers play an evolving role in the diagnosis of Alzheimer disease (AD). We compare conventional measurements of cerebrospinal fluid (CSF) tau and β-amyloid_1–42 proteins to a novel approach – Fourier transformed infrared (FT-IR) spectroscopy – a simple technique derived from chemical and physical sciences that characterizes intramolecular bonds. For automatic diagnostic analysis, we developed an artificial neural network (ANN). We examined 71 patients with a clinical diagnosis of AD and 66 controls. β-Amyloid_1–42 was decreased (sensitivity 80% and specificity 78%); tau was elevated (sensitivity 76% and specificity 88%) in CSF of AD patients. The combined tau/β-amyloid_1–42 quotient was able to distinguish healthy from diseased subjects with 99% sensitivity and 86% specificity. The ANN could separate FT-IR spectroscopy data with 88.5% sensitivity and 80% specificity. FT-IR spectroscopy proved to be cost-effective and simple to perform. Diagnostic sensitivity and specificity is in the range of CSF tau and β-amyloid_1–42 protein analysis. Larger sample numbers for ANN training and validation could increase diagnostic accuracy and thus prove to be a useful screening tool.     

An enzyme-based in situ hybridisation method for the identification of Streptococcus suis

A method for enzyme-based in situ hybridisation of Streptococcus suis was developed. It enables the light microscopic localization of bacterial ribosomal RNA (rRNA) in formalin-fixed paraffin-embedded tissues. A unique sequence in the 16S rRNA of S. suis was targeted. Different pretreatment protocols were applied to facilitate probe penetration and multiple detection systems were tested. The results were compared to those obtained by immunohistochemistry. Pretreatment was necessary to obtain a signal by in situ hybridisation. The use of proteinase-K pretreatment was optimal regarding sensitivity and preservation of tissue morphology. A strong specific in situ hybridisation signal was achieved in tissue sections containing S. suis in microcolonies and the microanatomy of the surrounding tissue was easily assessed. However, the signal distribution differed from that found immunohistochemically and low-grade infection could not be detected by in situ hybridisation. These findings were interpreted as reflecting the physiological state of the bacteria. Thus, this method could prove useful in future studies of the infection pathogenesis.     

丹参和黄芪治疗气虚血瘀型心力衰竭的作用

本文报道91例气虚血瘀型心力衰竭(心衰)病人选用丹参和黄芪治疗作用。16例作气囊漂浮导管监测,发现黄芪明显增加心排出量、每搏量及心脏指数,而丹参无此作用,提示黄芪有正性肌力作用;30例给黄芪加党参,治疗后心功能分级及某些异常的血液流变学指标均有改善;44例先丹参,继之丹参加黄芪,治疗后心功能分级有明显改善,且能改善异常的血液流变学指标,明显抑制血小板聚集功能。提示丹参具有活血化瘀改善血液流变学及抑制血小板的聚集性,黄芪有补气强心改善心功能的作用。     

False results associated with darkground microscopy of subgingival plaque

This study considers false results which may arise due to problems in the preparation or examination of specimens for darkground microscopy of subgingival plaque. Subgingival plaque samples obtained with a sterile curette were placed in 0.1-0.3 ml sterile full or 1/4 strength Ringer's solution: 0.85% saline, 1% gelatin in 0.85% saline, formal saline or pyrogen-free water for injection. Test slides were prepared from the original dispersion, and control slides from the corresponding sterile solution. Optimal dispersion solution, syringe dispersion frequency and the effect on motility of delay in processing samples were tested. Slides were also prepared from dispersions of 11 representative subgingival "periodontopathic" organisms. Problems in sampling included variability in counts between sites with comparable pocket depths, contamination of the sample and reduction of the sample volume after scaling. Problems in dispersion included contamination, uneven distribution of the different morphotypes and destruction of delicate organisms. Problems in slide preparation included slide contamination, limitation in the number of samples that can be assessed by one examiner at a given time without loss of activity of motile cells, and preparation of a cell monolayer. Problems in identification and counting included confusion of Brownian movements with motility, coccoid particles with cocci, spirochetes with campylobacter, flagella with flagella-like structures, size of cocci, counting of fragmented spirochetes and non-motile flagellated organisms and motile cells, and also bias in counting. Problems in morphotype grouping included the observation that many (10 of the 11 representative) periodontitis-related organisms were in the non-motile groups and not all cells of the motile species (Campylobacter, Capnocytophaga) showed motility. The results indicate that each stage of subgingival plaque darkground microscopy, sampling, dispersion, slide preparation, counting, morphotype grouping and interpretation may lead to false results if not representative or reproducible. Procedures are suggested for the minimisation of problems in the preparation and examination of subgingival plaque specimens for darkground microscopy.     

Application of the medical anti-shock trouser (MAST) increases cardiac output and tissue perfusion in simulated,mild hypovolaemia

We have studied the haemodynamic effects of the application of the medical anti-shock trouser (MAST) in 10 healthy subjects in the semi-upright position in order to simulate mild hypovolaemia. Left ventricular end diastolic dimension (EDD) was measured by M-mode echocardiography and cardiac output (CO) by the Doppler ultrasound technique. Forearm blood flow (FBF) was measured by plethysmography and blood pressure (BP) by the standard cuff technique. Systematic increases in MAST pressure of up to 80 mm Hg were applied. EDD increased to a maximum of 9.3% (p0.01) which was associated with a maximum increase in CO of 31.7% (p0.05). FBF increased by a maximum of 54.2% (p0.001) whilst BP increased by a maximum of 12% (p0.001). These results demonstrate that the application of the MAST is an effective means of transferring blood to the central circulation by compression of the capacitance vessels resulting in significant increases in cardiac output and tissue perfusion. At high pressures there was evidence of compression of resistance vessels, which may be useful in reducing blood loss. The ease and rapidity with which his suit can be applied suggests that it may be useful in the short term treatment of hypovolaemia.     

家庭社会经济地位对青少年主观幸福感影响的多重中介效应分析

目的:探讨家庭社会经济地位与青少年主观幸福感的关系及领悟社会支持和积极心理资本的中介作用。方法:采用家庭社会经济地位问卷、幸福感指数量表、领悟社会支持量表和积极心理资本问卷调查了932名青少年。结果:(1)家庭社会经济地位、领悟社会支持、积极心理资本和主观幸福感两两之间相关显著;(2)家庭社会经济地位对主观幸福感的直接效应不显著,但领悟社会支持、积极心理资本在家庭社会经济地位与主观幸福感之间的三条中介路径均显著。结论:为提升低家庭社会经济地位青少年主观幸福感,改善其领悟社会支持和积极心理资本水平是可实现的有效路径。     

长期未转阴新型冠状病毒肺炎患者 血清白蛋白水平与病毒转阴的因果关系探索

[摘要]　目的　初步探索血清白蛋白水平与新型冠状病毒肺炎长期阳性患者病毒转阴之间的因果关系。方法?以病程超过30 d的轻型新型冠状病毒肺炎住院患者为研究对象,采集人口学信息、治疗策略、合并疾病、实验室检查指标信息,以发病后45 d内病毒累积转阴率为因变量,以发病后（30±3）d时的血清白蛋白水平为主要分析变量,以人口学信息、治疗策略、合并疾病、实验室检查结果等其他信息为协变量,采用限制立方样条回归-Cox比例风险回归模型探讨血清白蛋白水平对累积转阴率的影响。结果?共有189例患者纳入分析,其中101例在45 d内实现了病毒转阴。进一步分析发现,30 d时的血清白蛋白水平与45 d病毒累积转阴率之间存在相关性（P = 0.027）。当血清白蛋白＜39 g/L时,低血清白蛋白水平是病毒转阴的危险因素,且血清白蛋白水平越低,风险比（hazard ritio, HR）越高,血清白蛋白越接近39 g/L,HR则越接近1;当血清白蛋白≥39 g/L时,血清白蛋白水平不再是病毒转阴的危险因素。结论?血清白蛋白水平与患者的病毒转阴密切相关,当血清白蛋白＜39 g/L时,血清白蛋白水平越低,越不利于病毒转阴。因此,治疗过程中关注血清白蛋白变化,及时给予干预,可能有利于病毒转阴。