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1.
Fetal nucleated erythrocytes (NRBC) in maternal blood are a non-invasive source of fetal DNA for prenatal genetic screening. We compared the effectiveness of three monoclonal antibodies for the separation of fetal cells from maternal blood by flow sorting. Mononuclear blood cells from 49 healthy pregnant women were incubated with antibody to CD 71, CD 36, and/or glycophorin A (GPA), employed singly or in combination with each other. These monoclonal antibodies recognize surface antigens on haematopoietic precursor cells. Successful isolation of fetal cells was defined as detection of Y chromosomal sequences in maternal blood from women carrying male fetuses, with absence of Y sequences when female fetuses were carried. Thus, gender prediction accuracy was used as a measure of fetal cell separation. Using anti-CD 71 to isolate fetal cells, gender prediction was 57 per cent correct; with anti-CD 36, it was 88 per cent correct. Anti-GPA, an erythrocyte-specific antigen, used alone or in combination with anti-CD 71 or 36, improved gender prediction to 100 per cent. We conclude that antibody to GPA improves the retrieval of fetal NRBC from maternal blood, permitting genetic analysis by the polymerase chain reaction.  相似文献   
2.
Monoclonal antibody to fetal haemoglobin (a2γy2) has been proposed as a fetal-specific reagent. We developed an intracellular staining protocol that combines fluorescein isothiocyanate or phycoerythrin conjugated anti-γ with the DNA binding dye Hoechst 33342 to identify and flow sort fetal erythroblasts from maternal blood. Our preliminary observations on anti-γ-positive cells sorted from four different pregnant women are described here, using fluorescence in situ hybridization (FISH) with chromosome-specific probes to identify fetal cells. Our data demonstrate that far fewer candidate fetal cells are sorted with this protocol than by current cell surface staining methods that employ the monoclonal antibody CD71. This results in increased fetal cell sorting purities. With this protocol, standard FISH techniques require modification due to the rigorous fixation with 4 per cent paraformaldehyde. Our initial data indicate the promise of this approach.  相似文献   
3.
The objective of this study was to detect fetal HLA-DQα gene sequences in maternal blood. HLA-DQα genotypes of 70 pregnant women and their partners were determined for type A1. We specifically sought couples where the father, but not the mother, had genotype A1. In 12 women, maternal blood samples were flow-sorted. Candidate fetal cells were isolated and amplified by using PCR primers specific for a paternal HLA-DQα A1 allele. Fetal HLA-DQα A1 genotype was predicted from sorted cells; amniocytes or cheek swabs were used for confirmation. Six of twelve sorted samples had amplification products indicating the presence of the HLA-DQα A1 allele; 6/12 did not. Prediction of the fetal genotype was 100 per cent correct, as determined by subsequent amplification of amniocytes or cheek swabs. We conclude that paternally inherited uniquely fetal HLA-DQα gene sequences can be identified in maternal blood. This system permits the identification of fetal cells independent of fetal gender, and has the potential for non-invasive prenatal diagnosis of paternally inherited conditions.  相似文献   
4.
The efficacy of the insulin infusion pump (CSII) in pregnancy was examined in 12 diabetic patients and compared with intermittent insulin therapy (IIT). In patients poorly controlled on IIT constant and rapid equilibrium was achieved with CSII (mean of glucose levels: CSII versus IIT=84 versus 137 mg/dl; S.D. = 36 versus 63 mg/dl; mean amplitude of glycemic excursion (MAGE)=65 versus 112 mg/dl. In patients well controlled on IIT, CSII led to a reduction in the variation of glucose excursions (S.D.= 29 versus 36 mg/dl; MAGE=48 versus 76 mg/dl). CSII generally produced a reduction of 20–37 per cent of daily insulin dose (in three cases there was an increase of dose with the achievement of glycemic control). Furthermore in CSII treated-patients amniotic glucose, insulin and C-peptide concentrations werefound tobeinthenormalrange(22.1±10.1 mg/dl; 5.2±2.7μ/ml; 1.25±0.71 ng/ml, respectively). All infants were horn at or near-term, had no macrosomia or neonatal problems. It is concluded that CSII is a highly efficient way to achieve normal glucose levels in pregnancy, not only in type I, hut also in type II or gestational diabetes.  相似文献   
5.
Several population studies relate exposure to high levels of arsenic with an increased incidence of ischemic heart disease and cardiovascular mortality. An association has been shown between exposure to high levels of arsenic and cardiovascular risk factors such as hypertension and diabetes mellitus, and vascular damage such as subclinical carotid atherosclerosis. The mechanisms underlying these phenomena are currently being studied and appear to indicate an alteration of vascular function. However, the effects of low levels of exposure to arsenic and their potential detrimental cardiovascular effect are less explored. The article provides an overview of the pathophysiologic mechanisms linking low-level arsenic exposure to the occurrence of cardiovascular disease and its complications, and some potential preventive strategies to implement.  相似文献   
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In Emilia-Romagna region (Northern Italy) the integrated waste treatment system consists of material collection and recycling, incineration with energy recovery and landfill as final disposal. In particular, at least one incineration plant is working in almost every province of the region. In this work, a screening life cycle assessment approach is applied to seven different incinerators, to compare the different plant technologies and identify the most relevant environmental impacts and processes. The characterization method used in the life cycle impact assessment step is Eco-indicator 99. The functional unit is 1 ton of waste input. As a first result, it can be noted that while the combustion systems are rather similar, the main variables are ascribable to gas cleaning options and efficiency in energy recovery, which result in quite different environmental performances. Among heavy metals, particular attention must be paid to Cd and As, due to their high toxicity, despite their low quantities. The impact due to dioxin emission is orders of magnitude lower than other contaminants (e.g., heavy metals). Furthermore, a catalytic system could be useful for a complete removal of organic contaminants and for a more effective abatement of nitrogen oxides. Finally, the environmental impact assessment sorts the various plants according to their age, i.e., the most recent plants provide the best environmental performances for the same quantity of combusted waste.  相似文献   
8.
The effect of different sewage concentrations (0, 20, 60 and 100%), vegetation (Bare, Avicennia marina or Rhizophora mucronata) and immersion periods (immersion/emersion period of 12/12 h or 3/3 days just for 100%) conditions were studied for 6 months on survival and growth rates of Terebralia palustris (Linnaeus, 1767). Gastropods' activity and ecosystem engineering preformed at bare and A. marina planted cells and 3 sewage conditions (0, 20 and 60%) were determined. Survival rates were higher than 70% in all treatments. Growth rate decreased significantly with increasing sewage concentrations (mainly at unplanted conditions) and longer immersion periods. A complete shift (from immersion to emersion periods) and a significant decrease in mobility and consequently its engineer potential, due to sewage contamination, lead to a 3-4 fold decrease in the amount of sediment disturbed. Sewage contamination, primary producers' abundance and environmental conditions may have influenced the gastropods survival, growth and its ecosystem engineering potential.  相似文献   
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10.
The incidence of testicular cancer (TC) has been increasing worldwide during the last decades. The reasons of the increase remains unknown, but recent findings suggest that organochlorine pesticides (OPs) could influence the development of TC. A hospital-based case-control study of 50 cases and 48 controls was conducted to determine whether environmental exposure to OPs is associated with the risk of TC, and by measuring serum concentrations of OPs, including p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) isomer and hexachlorobenzene (HCB) in participants. A significant association was observed between TC and household insecticide use (odds ratio [OR] = 3.01, 95 % CI: 1.11-8.14; OR(adjusted) = 3.23, 95 % CI: 1.15-9.11). Crude and adjusted ORs for TC were also significantly associated with higher serum concentrations of total OPs (OR = 3.15, 95 % CI: 1.00-9.91; OR(adjusted) = 3.34, 95 % CI: 1.09-10.17) in cases compared with controls. These findings give additional support to the results of previous research that suggest that some environmental exposures to OPs may be implicated in the pathogenesis of TC.  相似文献   
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