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1.
In the previous study, we reported that exposure to bisphenol-A induced the potentiation of dopamine receptor functions in the mouse limbic area, resulting in supersensitivity to methamphetamine-induced pharmacological actions. The present study was undertaken to investigate whether prenatal exposure to bisphenol-A could produce morphological change in dopaminergic neuron and the pattern of expression of genes regulating the dopaminergic neuron development. Here we found that prenatal and neonatal exposures to bisphenol-A increased the tyrosine hydroxylase- and dopamine transporter-like immunoreactivities in the adult mouse limbic area. The present molecular biological study shows that chronic bisphenol-A treatment produced a significant decrease in the dopaminergic neuron development factors, sonic hedgehog and glial cell line-derived neurotrophic factor, which were also decreased by prenatal exposure to bisphenol-A. These results suggest that chronic exposure to bisphenol-A could disrupt the dopaminergic neurotransmission in the process of dopaminergic neuron development.  相似文献   
2.
We have developed an immunoadsorbent (IA) for ex vivo removal of IgE after in vitro screening of matrix (Sepharose and tresyl-activated Toyopearl) and ligand (monospecific rabbit polyclonal anti-IgE antiserum and monoclonal antibodies (Abs) or their Fab fragments). Specific adsorptive capacity (SAC) for IgE was maximal in Sepharose-based IA with both types of Abs. Fab-containing IA on Sepharose retained 70-90% of the SAC of native Ab-containing IA. Toyopearl-based IA showed comparable SAC under static conditions but worked unsatisfactorily under continuous flow conditions. To assess the complement-activating capacity (CAC) of IA in vitro anaphylatoxin (C3a, C4a, C5a) generation was applied. CAC was directly related with the amount of immobilized Ab ligand, without depending on Ab specific activity. Fab-containing IA showed more CAC than native Ab-containing IA, and polyclonal IA more than monoclonal IA. Therefore, IA for IgE apheresis were prepared from native monoclonal Abs and CNBr-activated Sepharose CL 4B under aseptic conditions and packed into a glass column. This IA was used in 17 clinical IgE apheresis treatments of five atopic asthma patients. No substantial side effects were observed; in vivo IA effectively removed IgE from plasma (83 to 98%).  相似文献   
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4.
To examine the role of the apoptosis of macrophages and smooth muscle cells in the development of atherosclerosis, human aortic tissues with intimal lesions were immunostained with antibodies against terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL), single-stranded DNA (clone F7-26), and active caspase-3. Apoptotic cells were detected in the intima using both TUNEL and single-stranded DNA, however, the latter method was the more sensitive one for detecting apoptotic cells in the early stages of atherosclerosis. The number of apoptotic cells increased as the disease progressed. It implies that the apoptosis of intimal cells is involved in the formation of atherosclerotic lesions. In addition, quantitative analyses of the cell types undergoing apoptosis using double-immunostaining revealed that the susceptibility of macrophages and smooth muscle cells to apoptosis was greater specifically in atheroma than in the other atherosclerotic lesions, and macrophages were more susceptible to apoptosis than smooth muscle cells. The frequency and spatial distribution of oxidized low-density lipoprotein (oxLDL) (FOH1a/DLH3)-positive cells were examined by immunohistochemistry, and the results resembled those of apoptotic cells. The number of oxLDL-positive cells in the intima significantly correlated with the susceptibility of smooth muscle cells, but not with that of macrophages, to apoptosis. These results suggest that oxLDL affects the apoptosis of smooth muscle cells during the atherosclerotic development.  相似文献   
5.
To characterize apoptosis in keloids and the mechanisms responsible for this process, the expression of activated caspase-9 and -3 in fibroblasts obtained from keloids was analyzed. Immunohistochemistry revealed that the number of fibroblasts positive for terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL) or activated caspase-9 or -3 was low but was significantly higher in keloid tissues than in normal scar tissues. Significant relationships between the number of caspase-positive fibroblasts and TUNEL-positive fibroblasts suggested that the activation of caspase-9 and -3 induces apoptosis in a subpopulation of keloid fibroblasts. All keloid fibroblast cell lines established in this study showed activation of caspase-9 and -3 after serum deprivation for 3 or 4 hours, as shown using Western blotting. Furthermore, serum deprivation-induced apoptosis in a keloid fibroblast line was blocked by a caspase-9 inhibitor (acetyl-Leu-Glu-His-Asp-al), indicating that activation of caspase-9 was necessary for the process of apoptosis in keloid fibroblasts. Although serum deprivation did not significantly change the level of apoptosis protease activating factor-1 in any of the lines, cytochrome c release was detected in cytosolic fractions of the lines after serum deprivation for 3 or 4 hours. These results strongly suggest that keloid fibroblasts are predisposed to apoptosis and cytochrome c release and that caspase-9 activation may underlie regulation of apoptosis in keloid fibroblasts in vivo.  相似文献   
6.
The aim of this longitudinal study was to assess the effect of rotating shift work on perceived sleep quality and sleep duration of nurses at Queen Elizabeth Central Hospital, Blantyre, Malawi. Twenty four female nurses were recruited at random from among personnel engaged in rotating shift work. The nurses worked a three-phase schedule: five day shifts (7.00 – 17.00) followed by three night shifts (17.00 – 7.00) and five days off. Controls were 22 female nurses who did not perform night duties. Sleep quality and duration was assessed using standardized and validated questionnaires on sleep duration and subjective sleep quality (SSQ). One-way analysis of variance revealed a significant effect of shift phase on total sleep duration (F = 36.8, d.f. = 8, P < 0.000) and perceived sleep quality (F = 8.81, d.f. = 3, P < 0.000). Night shift work was associated with reduction of sleep quality and duration. The after effects of night shifts persisted during days of the recovery period indicating accumulation of fatigue.  相似文献   
7.
The prevalence of wheezing in children varies widely around the world. The reasons for this geographic variability remain unclear but may be related in part to exposures in the home environment during pregnancy and early childhood. We investigated the prenatal and early childhood risk factors for wheezing symptoms among 2127 children aged 6–8 years who were participants in the Ukrainian component of the European Longitudinal Study of Pregnancy and Childhood (ELSPAC). Cases included the 169 children whose parents answered yes to the International Study of Asthma and Allergy in Children (ISAAC) question: 'Has your child had wheezing or whistling in the chest in the past 12 months' during the ELSPAC assessment of the children at age 7. These were compared with the 1861 children in the cohort whose parents answered 'no' to this question.
Factors significantly associated with increased risk of wheezing illness at age 7 in adjusted analyses included mother's asthma [adjusted odds ratio (OR) 3.46, 95% confidence interval (CI) 1.22, 9.85]; mother's allergy problems (OR 1.43, [1.00, 2.05]); rarely playing with other children at age 3 (OR 1.84, [1.09, 3.11]); water intrusion (OR 1.62, [1.09, 2.39]) and inadequate heating of the home (OR 1.52, [1.06, 2.16]) during pregnancy. Factors protective of wheezing at age 7 included being first-born (adjusted OR 0.70, 95% CI 0.50, 0.98); living in the city of Dniprodzerzynsk as compared with Kyiv (OR 0.36, [0.24, 0.54]) and weekly contact with furry animals (OR 0.44, [0.20, 0.97]) before age 3. The constellation of risk factors for wheezing in Ukrainian children is similar to that of children in other parts of the world. Known risk factors do not account for the significant between-city variability of wheezing in Ukrainian children.  相似文献   
8.
The synthesis of boron-containing 1,3,5-triazines and 1,2,4-triazines is described. Derivatives of 1,3,5-triazine containing the o-carborane cluster have been obtained by reacting the corresponding propargyl derivatives with B(10)H(14). Derivatives of 1,2,4-triazine containing the B(12)H(12)(2-) cluster have been obtained by nucleophilic substitution of ethylsulfone derivatives with B(12)H(11)SH(2-). They have been isolated in their ring-protonated form. Reaction of RNH(2)-B(8)H(11)NH-R with stericly demanding heterocycles failed, either for steric or for solubility reasons.  相似文献   
9.
The influence of cold (+5° C), room temperature (+22° C) and hot (+75° C) air exposures on postactivation effects (PAE) in brachial biceps (BBs) and triceps (TBs) muscles were investigated bilaterally in six male subjects. PAE were evoked by 1 min volitional isometric contraction (VIC) at submaximal level in BBs by holding an inertial weight by palms, with right-angled elbows. At room temperature, average EMG during PAE (PAEav) usually was 2–4% and the integral of EMG (PAEint) was 3–7% of that of VIC respectively. PEA duration was 1–6 min. Cold exposure evoked an approximately two-fold increase of PAEint (P < 0.01). Hot exposure decreased PAEint (P < 0.01) and shortened PAE duration by approximately 50% (P < 0.01). In two subjects, long- term modulation of EMG intensity during PAE was observed. Cold increased the frequency and amplitude of these waves, while heat decreased them. In two subjects, alternation of BBs and TBs in EMG activity during PAE was observed. The data obtained suggest that postactivation of muscles strongly depends on the environmental temperature. Received: 15 February 1995/Received after revision: 19 June 1995/Accepted: 13 September 1995  相似文献   
10.
The effect of recombinant interleukin-4 on the synthesis of immunoglobulins is studied in a culture of mononuclear cells isolated from peripheral blood of healthy donors and patients with hay fever. It is shown that interleukin-4 stimulates production of IgE in cells of healthy donors, but not of hay fever patients, and does not affect the synthesis of other isotypes in either group. At the same time, increased cell proliferation under the influence of interleukin-4 was observed in cultured cells of both healthy donors and patients. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N o 10, pp. 426–428, October, 1994 Institute of Pulmonology, Ministry of Health, Moscow. (Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences)  相似文献   
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