Massively parallel sequencing of ataxia genes after array‐based enrichment

Massively parallel sequencing has tremendous diagnostic potential but requires enriched templates for sequencing. Here we report the validation of an array‐based sequence capture method in genetically heterogeneous disorders. The model disorder selected was AR ataxia, using five subjects with known mutations and two unaffected controls. The genomic sequences of seven disease genes, together with two control loci were targeted on a 2‐Mb sequence‐capture array. After enrichment, the patients' DNA samples were analyzed using one‐quarter Roche GS FLX Titanium sequencing run, resulting in an average of 65 Mb of sequence data per patient. This was sufficient for an average 25‐fold coverage/base in all targeted regions. Enrichment showed high specificity; on average, 80% of uniquely mapped reads were on target. Importantly, this approach enabled automated detection of deletions and hetero‐ and homozygous point mutations for 6/7 mutant alleles, and greater than 99% accuracy for known SNP variants. Our results also clearly show reduced coverage for sequences in repeat‐rich regions, which significantly impacts the reliable detection of genomic variants. Based on these findings we recommend a minimal coverage of 15‐fold for diagnostic implementation of this technology. We conclude that massive parallel sequencing of enriched samples enables personalized diagnosis of heterogeneous genetic disorders and qualifies for rapid diagnostic implementation. Hum Mutat 31:1–8, 2010. © 2010 Wiley‐Liss, Inc.     

Association of parental smoking behaviors and absences in school-age children: implications for the nurse practitioner

PURPOSE: To examine the association between reported absences and parental smoking in school-age children, aged 6-17, and to specifically explore the impact of maternal smoking on the health and attendance of school-age children. DATA SOURCES: The sample of 7488 parent-child dyads was randomly selected from the 2002 National Health Interview Survey, a multipurpose cross-sectional household interview survey conducted by the Centers for Disease Control and Prevention. The parent sample included 2673 men and 4375 women. Children's ages ranged from 6 to 17 with a mean of 11.7 years. CONCLUSIONS: Maternal, but not paternal, present and past smoking behavior significantly impacts the child's wellness and school attendance. The reasons for this disparity are unclear but may relate to synergistic effects of pre- and postnatal nicotine exposure, the traditional role of mother as caregiver, or specific smoking habits that increase environmental tobacco exposure. IMPLICATIONS FOR PRACTICE: Assessment and educational strategies for families regarding the hazards of childhood exposure to environmental tobacco smoke are indicated. Specific implications for the role of the nurse practitioner across diverse specialties are addressed with emphasis on the need for development of gender, age, and culturally sensitive smoking cessation programs and support networks.     

Environmental tobacco smoke exposure as a risk factor for infections in infancy

Aim:  This prospective observational study investigated the effect of environmental tobacco smoke (ETS) on frequency and severity of common infantile infections.
Methods:  In a representative sample of 926 infants, parental smoking was recorded at months 1 and 9 postpartum, and all infantile infectious episodes were recorded at 1, 3, 6, 9 and 12 months postpartum.
Results:  Both parents were regular smokers all through the first year in 107 (11.6%), at least one smoked regularly or occasionally in 492 (53.1%), and parents did not smoke at all in 327 (35.3%) families. Among mothers, 168 (18.1%) smoked perinatally. Infantile ETS exposure was associated with increased frequency of total infectious episodes (p = 0.025) and hospitalizations for infection (p = 0.007). In ETS exposed infants, birth in autumn and presence of siblings contributed to increased frequency of most infections and of hospital admissions for infection. By contrast, exclusive breastfeeding protected against the effect of ETS on total infantile infections (OR 0.982, 95% CI 0.965–0.999; p = 0.036), hospital admissions for infection (OR 0.980, 95% CI 0.961–0.999; p = 0.036) and thrush (OR 0.973, 95% CI 0.951–0.996; p = 0.022).
Conclusion:  Our findings point to harmful effect of ETS on infantile health and further suggest that this effect may be enhanced or diminished by other factors. ETS should be regarded as a preventable risk factor for infections in infancy.     

Olfactory perceptual learning requires adult neurogenesis

Perceptual learning is required for olfactory function to adapt appropriately to changing odor environments. We here show that newborn neurons in the olfactory bulb are not only involved in, but necessary for, olfactory perceptual learning. First, the discrimination of perceptually similar odorants improves in mice after repeated exposure to the odorants. Second, this improved discrimination is accompanied by an elevated survival rate of newborn inhibitory neurons, preferentially involved in processing of the learned odor, within the olfactory bulb. Finally, blocking neurogenesis before and during the odorant exposure period prevents this learned improvement in discrimination. Olfactory perceptual learning is thus mediated by the reinforcement of functional inhibition in the olfactory bulb by adult neurogenesis.     

环境刺激对缺氧缺血性脑损伤鼠突触结构的影响

目的 了解环境刺激对未成熟脑可塑性的影响及其在脑损伤后功能康复中的意义。 方法 选用雄性SD大鼠制作新生大鼠缺氧缺血性脑损伤(HIBD)模型,采用早期触摸和丰富环境刺激进行干预,观察大脑感觉运动皮层及海马CA3区突触超微结构参数的变化。结果 电镜下观察到2组大鼠两脑区均存在GRAY1型(即兴奋型)突触和穿孔突触。皮质部位干预组与非干预组比较,突触界面曲率和突触后致密物厚度(PSD)均增大,穿孔突触的百分比较高。海马部位干预组突触界面曲率和PSD厚度均较非干预组增大。结论 环境刺激对HIBD大鼠功能的促进作用可能与突触超微结构参数的改变,增强突触可塑性有关。     

Novel polymer-modified electrodes for batch injection sensors and application to environmental analysis

Various polymer coatings have been investigated for the protection of mercury thin-film electrodes in the square wave anodic stripping voltammetry of environmental samples using batch injection analysis, with injection of untreated samples of volume 50 μl directly over the sensing electrode. Polymer coatings studied include those with controlled porosity, and cation-exchange polymers based on sulphonated polymers. Of the polymers tested, films of ca. 1 μm thickness made from Nafion® mixed with 5% poly(vinyl sulphonic acid) were found to give the best results in tests with the model surfactants Triton-X-100 detergent, sodium dodecyl sulphate and protein standard. The validity of the approach is demonstrated by application to real samples.     

《公共场所卫生》教学改革实践

在我校2005级公共事业管理四年制本科专业《环境卫生学》的教学中，尝试对《公共场所卫生》内容进行教学改革，将理论课的授课地点由教室变为公共场所现场，通过组织学员自学相关内容、查阅文献、制订现场监测方案和实施现场监测，进而对监测结果进行交流和讨论，以促进学员的学习兴趣和对知识的掌握，从而做到学以致用，提高学员的实践能力和分析、解决问题的能力。     

Disinfection efficacy against parvoviruses compared with reference viruses

Some virus species can resist harsh environmental conditions, surviving on surfaces for long periods with the possibility of being transmitted to susceptible hosts. Studies are limited on the efficacy of disinfectants against viruses dried onto surfaces, in particular, with the identification of new pathogenic non-enveloped viruses that are expected to have high resistance to disinfection, such as parvoviruses. In this study a range of commonly used biocides, including heat, was tested against porcine parvovirus (PPV), minute virus of mice (a parvovirus), poliovirus type 1, adenovirus type 5, and vaccinia virus dried onto surfaces. PPV was the most resistant species identified, since many biocides generally considered as effective against non-enveloped viruses and used for high level disinfection demonstrated limited activity. Ethanol had poor activity against all non-enveloped viruses. Effectiveness against these viruses may be important in preventing nosocomial transmission of emerging pathogenic species such as bocavirus and other parvoviruses. This work confirms the need to validate disinfection products against viruses dried onto surfaces and demonstrates that PPV is a particularly resistant surrogate.