Quantified activity pattern data from 6 to 27-month-old farmworker children for use in exposure assessment

This study was conducted to describe exposure prone behaviors of infants and toddlers in the farmworker community. Analysis of hand and mouth contact frequencies and durations aids understanding of how children interact with their environment and are exposed via contact with surfaces. All 23 participating children (8 female infants, 5 male infants, 5 female toddlers and 5 male toddlers) lived with at least one farmworker. Children were videotaped at home for 2-6 h. Video footage was translated into micro-level activity time series (MLATS) for both hands and the mouth. MLATS were processed to calculate hourly duration in microenvironments, contact frequency, hourly contact duration and median contact duration. The median hourly duration spent indoors was 53 min/h. The median hand-to-mouth frequency was 15.2 events/h and the median object-to-mouth frequency was 27.2 events/h. The hourly mouthing duration was 1.2 and 2.2 min/h with the hands and objects, respectively. The median mouthing duration with hands and objects was 2 s. The median contact frequency for both hands combined was 689.4 events/h with an hourly contact duration of 100.5 min/h and a median contact duration of 3 s. Infants had higher mouthing frequencies with non-dietary objects while toddlers had higher mouthing frequencies with objects associated with pica (i.e., paper). Boys had higher contact frequencies while girls had longer contact durations. These sub-group differences indicate factors such as age and gender should be accounted for when conducting exposure assessments. Contact frequencies in this study are higher than current US EPA recommendations, questioning their protective value for infants and toddlers.     

A genetically engineered chimeric vaccine against porcine circovirus type 2 (PCV2) is genetically stable in vitro and in vivo

A vaccine against porcine circovirus type 2 (PCV2), designated PCV1-2 chimera, was recently developed by replacing the capsid gene of the non-pathogenic PCV1 with that of PCV2. The PCV1-2 chimera virus is attenuated in pigs but induces protective immunity against PCV2. In this study, the genetic stability of the PCV1-2 chimera was evaluated for its potential use as a live vaccine. The PCV1-2 chimera virus was serially passaged 11 times in PK-15 cells and 3 times in pigs. The PCV1-2 chimera virus used in this study contained a tracking marker mutation in the capsid gene (F to V at amino acid position 79). Sequence analyses of the PCV1-2 chimera virus after 11 serial passages in PK-15 cells did not reveal any sequence change including the marker mutation. Similarly, there is no change in the genomic sequence of the PCV1-2 chimera virus recovered from pigs during 3 serial in vivo passages. Under in vivo selection pressure, however, the introduced tracking marker mutation in the PCV1-2 chimera quickly mutated (V79F) and restored to its original sequence after one passage in pigs, and remained stable in subsequent 2 passages in pigs. The results indicate that the PCV1-2 chimera virus is genetically stable, and thus should be a good vaccine candidate.     

Use of propofol and emergence agitation in children: a literature review

Emergence agitation (EA) is an important issue in pediatric anesthesia. This phenomenon arises more frequently with the use of inhalational agents. Three commonly used general anesthesia techniques in children were evaluated as to the associated incidence of emergence reactions. An extensive literature review was performed to evaluate these anesthetic practices and the occurrence of EA in young children. Relevant literature was obtained from multiple sources, including professional journals, professional websites, and textbooks. Three categories of anesthesia techniques were reviewed: sevoflurane inhalational general anesthetic, Emerpropofol as an adjunct to sevoflurane general anesthetic, and propofol total intravenous anesthesia (TIVA) techniques. Several variables within each category were evaluated with respect to the outcome of EA: prevention, intraoperative adjuncts, type of surgery, and patient-related factors. According to the literature evidence base, there is an advantage to either propofol TIVA or adjunctive propofol with sevoflurane (compared with sevoflurane alone). We conclude, based on the current evidence, that the use of propofol is associated with a reduction in the incidence of emergence agitation.     

The Effects of Intracellular Glutathione Content on the Sensitivity of Methylseleninic Acid to Human High-metastatic Large Cell Lung Cancer Cell Line L9981

Background and objective Lung cancer has not only become the most frequent malignant cancer which is increasing fastest among all the tumors, but also become the rst killer which     

自噬与胶质瘤治疗研究

自噬是胞浆长寿命蛋白质和细胞器在膜包囊泡中大量降解的生物学过程。自噬与人类的多种疾病。尤其是恶性肿瘤存在密切关系。外科手术是神经胶质瘤的主要治疗手段,其他的辅助治疗手段如放射治疗、化学治疗对提高胶质瘤的治疗效果具有重要意义。此外,生物免疫治疗、基因治疗和热疗等新的治疗手段对胶质瘤也具有一定的效果。本文对自噬在胶质瘤治疗中的作用进行了概述。     

缺血／再灌注对大鼠心肌线粒体电子传递与质子泵出偶联的影响

本实验采用Ｌａｎｇｅｎｄｏｒｆｆ灌流装置造成大鼠心肌缺血／再灌模型，用差速离心法分离线粒体，用Ｃｌａｒｋ氧电极测定ＲＣＲ，ＡＤＰ／Ｏ，用铁氰化钾脉冲法测定了呼吸链电子传递及质子泵出初速度。结果表明，Ｈ＾＋／２ｅ在缺血时与对照比无显著差异，而再灌组显著低于对照，Ｈ＾＋／２ｅ下降早于ＡＤＰ／Ｏ下降。ＲＣＲ、ＡＤＰ／Ｏ在缺血早期及再灌时显著高于对照。     

New antiserum against Ki-67 antigen suitable for double immunostaining of paraffin wax sections.

AIMS--To prepare a rabbit antiserum equivalent to MIB 1 to permit the simultaneous assessment of cell proliferation and other markers of interest using double labelling studies. METHODS--Rabbits were immunised with a synthetic peptide deduced from the cDNA sequence coding for the Ki-67 antigen. Serum samples were tested for immunoreactivity using different immunobiochemical methods. RESULTS--A polyclonal antiserum was derived which detects the native as well as recombinant parts of the Ki-67 antigen in different test systems. Furthermore, the antiserum stains the Ki-67 antigen in routinely processed, paraffin wax embedded material. CONCLUSIONS--After antigen unmasking by microwave treatment the antiserum described here represents a powerful tool for the determination of growth fractions even in archival material. It is especially suitable for double staining experiments in combination with monoclonal antibodies.