Perinatal toxicity and carcinogenicity studies of styrene-acrylonitrile trimer,a ground water contaminant

Styrene acrylonitrile (SAN) trimer is a by-product in the production of acrylonitrile styrene plastics. Following a report of a childhood cancer cluster in the Toms River section of Dover Township, New Jersey, SAN Trimer was identified as one of the groundwater contaminants at Reich Farm Superfund site in the township. The contaminants from the Reich Farm site's ground water plume impacted two wells at the Parkway well field. The National Toxicology Program (NTP) studied the toxicity and carcinogenicity of SAN Trimer in rats exposed during their perinatal developmental period and adulthood. The chronic toxicity and carcinogenicity studies in F344/N rats were preceded by 7- and 18-week perinatal toxicity studies to determine the exposure concentrations for the 2-year studies. Subsequently, Fisher 344 pregnant dams were exposed to SAN Trimer containing diet at 400, 800, or 1600 ppm concentrations during gestation, nursing and weaning periods of offspring followed by two year of adult exposures to both male and female pups. There was no statistically significant evidence of carcinogenic activity following SAN-Trimer exposure; however, rare neoplasms in the brain and spinal cord were observed in males and to lesser extent in female rats. These incidences were considered within the range of historical background in the animal model used in the current studies. Therefore, the presence of a few rarely occurring CNS tumors in the treated groups were not judged to be associated with the SAN Trimer exposure. The major finding was a dose-related peripheral neuropathy associated with the sciatic nerves in females and spinal nerve roots in males and females thereby suggesting that SAN Trimer is potentially a nervous system toxicant.     

我国早产儿视网膜病变的筛查现状

早产儿视网膜病变(ROP)是一种属于可避免、可控的儿童主要致盲性及低视力眼病。筛查是早检出、早干预和早治疗的前提和关键措施，对降低儿童致盲率及视力损伤具有重要意义。本文主要对我国ROP筛查和发病现状作一综述，以期为ROP的防治提供参考。     

The pediatric surgeon–patient relationship

Though technical aspects of surgical practice are commonly emphasized, communication is the most frequent “procedure” employed by surgeons. A good patient–physician relationship enhances the quality of surgical care by improving outcomes and patient and family satisfaction. There are general principles that can enhance communication with all children and families. Employing a developmentally sensitive approach that adjusts communication style based on a child's cognitive abilities and emotional concerns can further enhance the relationship with children of different ages. These communication skills can be learned and are improved by practice and self-reflection.     

The encoding of word forms into memory may be challenging for college students with developmental language impairment

Purpose: To describe the word-learning problems characteristic of developmental language impairment (LI).

Method: College students with LI (n?=?39) or normal language development (ND, n?=?40) attempted to learn novel word forms. Training for half of the words was meaning-focused; training for the other half was form-focused. Form recognition and stem completion tasks administered immediately after training tapped encoding of the lexical configuration and a repetition of the stem completion task one week later tapped consolidation. A visual world paradigm tapped lexical engagement.

Result: At the immediate post-test, the LI group was poorer at recognition and completion of word forms than their ND peers, suggesting a deficit in encoding the lexical configuration. However, the gap between the LI and ND groups in stem completion did not grow over the week, suggesting intact consolidation. Form-focused training yielded better performance than meaning-focused training at immediate- and one week tests. For both groups, newly trained words slowed the recognition of familiar English words, revealing lexical engagement.

Conclusion: The encoding of word-form configurations is challenging for some, but not all, college students with LI. Training that encourages a focus on the form may be a useful part of vocabulary intervention for those affected.     

Persistent proteomic changes in glutamatergic and GABAergic signaling in the amygdala of adolescent rats exposed to chlorpyrifos as juveniles

Chlorpyrifos (CPF) remains one of the most widely used organophosphorus insecticides (OPs) despite the concerns about its developmental neurotoxicity. Developmental exposure to CPF has long-lasting negative impacts, including abnormal emotional behaviors. These negative impacts are observed at exposure levels do not cause inhibition of acetylcholinesterase, the canonical target of OPs. Exposure to CPF at these levels inhibits the endocannabinoid metabolizing enzyme fatty acid amide hydrolase (FAAH) but it is not clear what the persistent effects of this inhibition are. To investigate this, male rat pups were exposed orally to either corn oil, 0.75 mg/kg CPF, or 0.02 mg/kg PF-04457845 (PF; a specific inhibitor of FAAH) daily from postnatal day 10 (PND10) - PND16. This dosage of CPF does not inhibit brain cholinesterase activity but inhibits FAAH activity. On PND38 (adolescence), the protein expression in the amygdala was determined using a label-free shotgun proteomic approach. The analysis of control vs CPF and control vs PF led to the identification of 44 and 142 differentially regulated proteins, respectively. Gene ontology enrichment analysis revealed that most of the proteins with altered expression in both CPF and PF treatment groups were localized in the synapse-related regions, such as presynaptic membrane, postsynaptic density, and synaptic vesicle. The different biological processes affected by both treatment groups included persistent synaptic potentiation, glutamate receptor signaling, protein phosphorylation, and chemical synaptic transmission. These results also indicated disturbances in the balance between glutamatergic (↓ Glutamate AMPA receptor 2, ↓ Excitatory amino acid transporter 2, and ↑ vesicular glutamate transporter 2) and GABAergic signaling (↑ GABA transporter 3 and ↑ glutamate decarboxylase 2). This imbalance could play a role in the abnormal emotional behavior that we have previously reported. These results suggest that there is a similar pattern of expression between CPF and PF, and both these chemicals can persistently alter emotional behavior as a consequence of inhibition of FAAH.     

Physical development in children and adolescents with bronchial asthma

Bronchial asthma is the most common chronic disease in children of developmental age. Data from the auxological literature indicate that children with disturbances in growth may also suffer from atopic disorders. The aim of the present study was to evaluate somatic growth in children with bronchial asthma using anthropological methods. The study was carried out using anthropometric measurements and information on the severity and course of the disease on 261 children with bronchial asthma. Mean body height was lower than in healthy peers and about 5% of subjects were short. Mean BMI and skinfold thicknesses were significantly higher and lean body mass was lower in the study group. Seventeen percent of the children were overweight or obese, and 8% were underweight. Body build was more robust in the girls examined. Longitudinal studies will help determine to what degree the disease itself directly affects physical development, and to what degree treatment does.     

社区护士手卫生知识知晓情况及影响因素研究

摘要〓目的〓了解社区护士对手卫生知识的知晓率情况,深度分析影响社区护士手卫生的相关因素。方法〓采用便利抽样的方法选取长春市的4个行政区,用整群抽样法抽取25家社区卫生机构的252名护士,对手卫生知识进行问卷调查。应用单因素和多元线性回归法对调查结果进行统计学分析。结果〓社区护士手卫生知晓率总分为16.73±2.15,单因素分析显示,不同年龄、工龄、职称和受教育程度对手卫生知识知晓率影响有统计学意义(P<0.05)。多元线性回归显示,工龄、文化程度和职称是社区护士手卫生知识知晓率的影响因素。结论〓长春市社区护士手卫生知识知晓率水平较低,管理者应采取相应措施来提高护士手卫生知识知晓率,有效防止社区卫生机构感染的发生。