Tumor vascular signals in renal masses: detection with Doppler US

The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.     

新冠疫情期间家庭环境对初中生非自杀性自伤的影响:抑郁的中介作用

  目的  了解新型冠状病毒感染疫情（新冠疫情）期间成都市初中生非自杀性自伤（non-suicidal self-injury, NSSI）的发生现状,探讨抑郁在家庭环境与NSSI间的作用机制。  方法  数据来源于成都儿童正向成长队列（Chengdu Positive Child Development, CDPD）,于2020年6–7月成都市中小学因新冠疫情关闭解封后,采用蓄意自伤量表（Deliberate Self-Harm Inventory, DSHI）、中国家庭评估测量工具（Chinese Family Assessment Instrument, C-FAI）、流调中心儿童抑郁量表（Center for Epidemiologic Studies Depression Scale for Children, CES-DC）进行现场问卷获得3595名初中生调查资料。采用两样本t检验和χ2检验,比较不同年级和性别初中生的NSSI发生率,利用SPSS PRECESS组件Model 58检验分析性别调节下抑郁的中介作用。  结果  ①新冠疫情期间成都市初中生的NSSI发生率为49.67%,九年级学生的NSSI发生率（80.70%）,高于八年级（33.82%）和七年级（32.32%）,初中女生的NSSI发生率（54.75%）高于男生（44.52%）;②家庭环境（r=0.34, P<0.001）、抑郁（r=0.50, P<0.001）与NSSI呈正相关;③抑郁在家庭环境对NSSI的影响中起部分中介作用,中介效应占总效应的64.64%;与男生相比,初中女生在家庭环境与抑郁、抑郁与NSSI的正向预测作用更加显著。  结论  新冠疫情期间,成都市初中生NSSI发生率较高,提示应改善家庭环境,关注性别差异,加强抑郁的早期筛查和干预,以减少NSSI发生。     

Brain-specific chemical delivery systems for beta-lactam antibiotics. Synthesis and properties of some dihydropyridine and dihydroiosquinoline derivatives of benzylpenicillin

Six chemical delivery systems (CDS) were synthesized for benzylpenicillin in order to improve its transport across the blood-brain barrier. The CDS's were based on a dihydropyridine----quaternary pyridinium ion redox system, analogous to the naturally occurring NADH----NAD+ system. Two different types of CDS's were prepared: benzylpenicillin esters of diols in which the other hydroxyl group is esterified by dihydrotrigonelline and benzylpenicillin esters of amino alcohols in which the amine group is acylated by dihydrotrigonelline, or by 1,2-dihydro-2-methyl-4-isoquinolinecarboxylic acid. Lipophilicities of the CDS's were proved to be much higher than those of benzylpenicillin by using Rm values as lipophilicity indexes. Upon oxidation, all of the CDS's gave the quaternary ion forms. Kinetic studies in buffer (pH profiles) indicated that the quaternary salts released benzylpenicillin in pH range of 5-9 via hydrolysis. The CDS's in acidic media yielded as the major reaction product 6-hydroxy-1,4,5,6-tetrahydropyridines as a result of water addition, while in basic conditions benzylpenicillin was released. The water addition reaction was dependent on the CDS's structure, being more prevalent in the case of the "amide-esters". The dihydroisoquinoline CDS was rather stable in the pH range 5-8.     

Reliability and factorial structure of the Chinese version of the General Health Questionnaire

The Chinese version of the General Health Questionnaire (GHQ) was administered to 2,150 Chinese secondary school students. The GHQ was found to have high internal consistency as a scale and high item-total correlations for most of the items. Factor analysis with a five-factor solution showed that five factors were abstracted from the scale, namely, anxiety, depression, inadequate coping, interpersonal dysfunctioning, and sleep disturbances. By randomly splitting the total sample into two subsamples, these five factors could be reproduced reliably, and high coefficients of congruence were found. The psychometric properties of the Chinese version of the GHQ and the implications of the findings were discussed.     

Natural and immune cytolysis of canine distemper virus-infected target cells.

Natural and immune cytolysis of canine distemper virus (CDV)-infected target cells in vitro is described. Lymphocytes expressing natural cytotoxicity were found in specific-pathogen-free beagle dogs and in beagle-coonhound crosses before vaccination with CDV and indefinitely after vaccination, when the ephemeral immune lymphocyte-mediated cytotoxicity (ILMC) had declined. In contrast to the natural lymphocyte-mediated cytotoxicity, the ILMC was genetically restricted, could not be blocked by CDV-specific antibody, and was effective against measles virus-infected as well as CDV-infectd target cells. Lymphocyte populations were depleted of Fc receptor and surface immunoglobulin-bearing cells by rosetting techniques and tested in comparison. An antibody-dependent cell-mediated cytotoxicity was demostrated against CDV-infected target cells that were preincubated with CDV antibody when Fc receptor-bearing lymphocytes were not removed. The ILMC was measurable for approximately 10 days beginning at 6 days post-vaccination. In contrast, CDV antibody measured by virus neutralization and humoral cytotoxicity was detectable by 6 days postvaccination and persisted at peak levels for at least 5 months.