Community characteristics associated with elevated blood lead levels in children

OBJECTIVES: To identify community characteristics associated with children having elevated blood lead levels (> or = 10 micrograms/dL) and examine whether these characteristics can be used to identify children with elevated blood lead levels. PARTICIPANTS AND SETTING: A total of 20,296 children in Monroe County, New York (< 6 years old) who had blood lead testing in the first 12 months after statewide mandated reporting of blood lead tests began. DESIGN: A logistic regression analysis was conducted to examine the association of children's blood lead levels and community characteristics by using community characteristics of 653 census block groups. RESULTS: The following community level variables were associated with increased risk of elevated blood lead levels in children: residence within the city [odds ratio (OR), 2.0; 95% confidence interval (CI), 1.6, 2.7]; block groups with a higher proportion of individuals of Black race (OR, 1.6; CI, 1.4, 2.0); higher screening rate (OR, 1.9; CI, 1.6, 2.4); lower housing value (OR, 1.6; CI, 1.2, 2.0); housing built before 1950 (OR, 1.5; CI, 1.3, 1.8); higher population density (OR, 1.5; CI, 1.3, 1.8); higher rates of poverty (OR, 1.4; CI, 1.2, 1.8); lower percent of high school graduates (OR, 1.3; CI, 1.1, 1.6), and lower rates of owner-occupied housing (OR, 1.2; CI, 1.0, 1.4). Community characteristics were comparable with clinic-based individual risk assessment to identify children with elevated blood lead levels. CONCLUSIONS: These data demonstrate that community characteristics can be used to develop screening strategies to identify children who have elevated blood lead levels and shift our efforts toward identifying houses containing lead hazards before occupancy and before children are unduly exposed.     

Use of rifampicin and ciprofloxacin combination therapy after surgical debridement in the treatment of early manifestation prosthetic joint infections

Prosthetic joint infections are difficult to eradicate, and antibiotic and surgical treatment strategies lack standardisation. The present study followed 29 patients (median age 72 years, median American Society of Anesthesia score of two) with early prosthetic joint infections. Treatment consisted of device retention, surgical debridement and therapy with rifampicin and ciprofloxacin for 3 months. This treatment regimen failed in five patients during the study, with a median observation period of 674 days. The results of this study confirm the findings of the only previous study on device retention with antibiotic treatment.     

Detection and traceability of genetically modified organisms in the food production chain.

Both labelling and traceability of genetically modified organisms are current issues that are considered in trade and regulation. Currently, labelling of genetically modified foods containing detectable transgenic material is required by EU legislation. A proposed package of legislation would extend this labelling to foods without any traces of transgenics. These new legislations would also impose labelling and a traceability system based on documentation throughout the food and feed manufacture system. The regulatory issues of risk analysis and labelling are currently harmonised by Codex Alimentarius. The implementation and maintenance of the regulations necessitates sampling protocols and analytical methodologies that allow for accurate determination of the content of genetically modified organisms within a food and feed sample. Current methodologies for the analysis of genetically modified organisms are focused on either one of two targets, the transgenic DNA inserted- or the novel protein(s) expressed- in a genetically modified product. For most DNA-based detection methods, the polymerase chain reaction is employed. Items that need consideration in the use of DNA-based detection methods include the specificity, sensitivity, matrix effects, internal reference DNA, availability of external reference materials, hemizygosity versus homozygosity, extrachromosomal DNA, and international harmonisation. For most protein-based methods, enzyme-linked immunosorbent assays with antibodies binding the novel protein are employed. Consideration should be given to the selection of the antigen bound by the antibody, accuracy, validation, and matrix effects. Currently, validation of detection methods for analysis of genetically modified organisms is taking place. In addition, new methodologies are developed, including the use of microarrays, mass spectrometry, and surface plasmon resonance. Challenges for GMO detection include the detection of transgenic material in materials with varying chromosome numbers. The existing and proposed regulatory EU requirements for traceability of genetically modified products fit within a broader tendency towards traceability of foods in general and, commercially, towards products that can be distinguished from each other. Traceability systems document the history of a product and may serve the purpose of both marketing and health protection. In this framework, segregation and identity preservation systems allow for the separation of genetically modified and non-modified products from "farm to fork". Implementation of these systems comes with specific technical requirements for each particular step of the food processing chain. In addition, the feasibility of traceability systems depends on a number of factors, including unique identifiers for each genetically modified product, detection methods, permissible levels of contamination, and financial costs. In conclusion, progress has been achieved in the field of sampling, detection, and traceability of genetically modified products, while some issues remain to be solved. For success, much will depend on the threshold level for adventitious contamination set by legislation.     

MEASUREMENT OF ROOT CANAL LENGTH – USE OF AN ELECTROMETRIC DEVICE

The measurement of root canal length is a pre-requisite for successful pulpectomy. The conventional manual and radiographic methods are not very accurate. In the present study, odontometer was used [Group B) to assess its efficacy over the conventional methods (Group A) for recording root canal length. In group A, 36 teeth were treated with pulpectomy while in group B, 51 teeth were managed by the same treatment. It was observed that post operative complications in group B were significantly less (p < 0.05). The odontometer proved to be an excellent device for rapid and accurate measurement of root canal length.KEY WORDS: Pulpectomy, Root canal length, Odontometer     

Human fetal bone marrow early progenitors for T, B, and myeloid cells are found exclusively in the population expressing high levels of CD34

Experimentation on human stem cells is hampered by the relative paucity of this population and by the lack of assays identifying multilineage differentiation, particularly along the lymphoid lineages. In our current study, phenotypic analysis of low-density fetal bone marrow cells showed two distinct populations of CD34+ cells: those expressing a high density of CD34 antigen on their surface (CD34hi) and those expressing an intermediate level of CD34 antigen (CD34lo). Multiple tissues were used to characterize the in vitro and in vivo potential of these subsets and showed that only CD34hi cells support long-term B lymphopoiesis and myelopoiesis in vitro and mediate T, B, and myeloid repopulation of human tissues implanted into SCID mice. CD34lo cells repeatedly failed to provide long-term hematopoietic activity in vivo or in vitro. These results indicate that a simple fractionation based on well-defined CD34 antigen levels can be used to reproducibly isolate cells highly enriched for in vivo long-term repopulating activity and for multipotent progenitors, including T- and B-cell precursors. Additionally, given the limited variability in the results and the high correlation between in vitro and in vivo hematopoietic potential, we propose that the CD34hi population contains virtually all of the stem cell activity in fetal bone marrow and therefore is the population of choice for future studies in hematopoietic stem cell development and gene therapy.     

采用蛋白指纹图谱技术筛选大肠癌肝转移特异性相关蛋白

目的:应用表面增强激光解析电离飞行时间质谱技术从大肠癌及大肠癌肝转移患者中筛选出大肠癌肝转移患者血清特异性相关蛋白。方法:实验于2005-07/2006-09分别在南方医院消化中心实验室与解放军第一五○医院实验室完成。应用美国CipherGen公司IMAC3(ImmobilizedMetalAffinityCapture,金属亲和表面)芯片和蛋白芯片仪检测44例大肠癌患者及36例大肠癌肝转移患者血清中的蛋白质相对含量。设定所有血清样本检测的蛋白质相对分子质量区间在1500～20000。利用PBSⅡ型蛋白质芯片阅读仪对IMAC3芯片进行检测,所得到的蛋白质以波谱的形式表示。采用BiomarkerWizard软件对2组血清在相同质荷比的蛋白质含量数据进行方差分析,将分析所得到的含量有显著性差异(P<0.05)的蛋白质建立数据库,导入BiomarkerPattern智能统计分析软件,选择相应条件,对其进行分组统计,从而得到能够正确分组的特异性蛋白标志物并构建大肠癌肝转移的诊断模型。采用酶联免疫法检测相同血清标本中的CEA水平,与构建的诊断模型在大肠癌肝转移诊断中作比较。结果:①44例大肠癌患者与36例大肠癌肝转移患者的血清蛋白质在质荷比为2685.64～11813间有16个蛋白质含量有显著差异。②大肠癌组在质荷比为5909处的蛋白质的相对含量高于大肠癌肝转移组[(30.1±9.6)%,(14.5±10.4)%,P≤0.01]。③其中44例大肠癌患者中有38例患者被正确分组,36例大肠癌肝转移患者被正确识别,准确率为92.5%(74/80),灵敏度和特异性分别为100%(36/36),86.4%(38/44)。结论:表面增强激光解析电离飞行时间质谱技术快速、准确、灵敏度、特异性高,通过蛋白芯片仪发现的特异性相关蛋白,有望成为大肠癌肝转移诊断中有应用价值的临床检测指标。