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61.
Background: Currently, to our knowledge, quality of output water of dental chair units is not covered by specific regulations in the European Union, and national recommendations are heterogeneous. In Germany, water used in dental chair units must follow drinking water quality. In the United States of America, testing for aerobic heterotrophic bacteria is recommended. The present study was performed to evaluate whether the counts of aerobic heterotrophic bacteria correlate with the presence of potentially pathogenic bacteria such as Legionella spp. or Pseudomonas aeruginosa. Methods: 71 samples were collected from 26 dental chair units with integrated disinfection device and 31 samples from 15 outlets of the water distribution pipework within the department were examined. Samples were tested for aerobic heterotrophic bacteria at 35°C and 22°C using different culture media and for Legionella spp. and for Pseudomonas aeruginosa. Additionally, strains of Legionella pneumophila serogroup 1 were typed with monoclonal antibodies and representative samples of Legionella pneumophila serogroup 1 were typed by sequence based typing.Results: Our results showed a correlation between different agars for aerobic heterotrophic bacteria but no correlation for the count of aerobic heterotrophic bacteria and the presence of Legionella spp. or Pseudomonas aeruginosa.Conclusion: Testing for aerobic heterotrophic bacteria in output water or water distribution pipework within the departments alone is without any value for predicting whether the water is contaminated with potentially pathogenic bacteria like Legionella spp. or Pseudomonas aeruginosa.  相似文献   
62.
Purpose: Oxidative stress, which refers to the biological damage caused by free radicals produced in excess of innate antioxidant defenses, is indicated in the ocular cancer retinoblastoma (RB). Here we have analysed the differential expression of oxidative stress responsive genes in oxidant-induced RB cells, and in RB tumor tissues. Methods: The study included cultured RB cells, and four RB tumor tissues. The reactive oxygen species (ROS) levels in Y79 cells and the RB tumor induced by hydrogen peroxide were quantified by Dichlorofluorescein (DCF) fluorescence assay. We then analysed the gene expression profile of cultured RB cells induced with hydrogen peroxide (400 μM H(2)O(2) for 8 h) by microarray analysis, and the expression of select genes were validated in Y79 cells and RB tumor tissues by real-time PCR analysis. Results: The oxidant-induced RB tumors showed an average increase in ROS levels of 44-fold compared to induced non-neoplastic donor retina. H(2)O(2)-induced RB cell line showed a 3-fold increase in ROS levels. Microarray analysis on RB cell line induced with H(2)O(2) showed differentially regulated genes involved in cellular processes such as: oxidative stress, angiogenesis, lipid metabolism, cell proliferation, and cell signaling pathways. Several up-regulated genes such as SOD, GPX, CAT, CDC25A, CREBBP, JUN, MMP-2, iNOS, CRYAA, RXRA, ACACB and HMGCR were validated by real-time PCR. These results corroborated with the gene expression analysis in RB tumor tissues. Relating the antioxidant gene expression with the clinico-pathologic features of the tumor tissues, we found that the tumor with invasion of choroid, optic nerve and retinal pigment epithelium, had relatively higher ROS levels and minimal antioxidant gene expression, when compared with the tumor with only choroidal invasion. Conclusions: The study suggests active involvement of redox signaling pathways in the pathogenesis of RB. Consideration of oxidative stress components in the clinical management of RB patients is emphasized.  相似文献   
63.
Background: Taxation and other policy measures have been implemented across the United States to curb the accessibility of substance use, especially among youth. While the inverse relationship between price and youth consumption is well known, available research on youth earned income and substance use is sparser, particularly among emerging adults. Objectives: We examined the association between emerging adult past-year personal income and 30-day substance use. Methods: We analyzed data from Wave 5 (n = 2,202) of the NEXT Generation Health Study, an annual survey study administered to a nationally representative sample of emerging adults in the U.S. Wave 5 (mean age = 20.28 years, SE = 0.02 years) was administered during the 2013–2014 academic year. After grouping participants into five levels of self-reported, pre-tax personal income, we used binomial logistic regression to examine the association between personal income and cigarette smoking, marijuana use, alcohol use, and heavy episodic drinking (HED). Results: In unadjusted models, those at certain levels of higher past-year income were more likely to smoke cigarettes, consume alcohol, or engage in HED at least once in the past 30 days. Several associations remained significant after controlling for covariates. Most associations were no longer significant after including perceived peer norms as additional covariates. Personal income was not associated with 30-day marijuana use in unadjusted or adjusted models. Conclusions/Importance: Higher earned income may provide emerging adults greater economic access to cigarettes and alcohol, but the association might be partly attenuated by social factors, particularly perceived peer norms.  相似文献   
64.
We detected the simian malaria parasites Plasmodium knowlesi, P. cynomolgi, P. inui, P. coatneyi, P. inui–like, and P. simiovale among forest fringe–living indigenous communities from various locations in Malaysia. Our findings underscore the importance of using molecular tools to identify newly emergent malaria parasites in humans.  相似文献   
65.
Cervical cancer is the second leading cause of cancer deaths among women worldwide. High-Risk-Human Papillomaviruses (HR-HPVs) play an important etiologic role in the development of carcinoma of the uterine cervix. However, host factors are important in determining the outcome of genital HPV infection as most cervical precancerous lesions containing HR-HPVs do not progress to invasive carcinomas. Retinoids, acting through nuclear receptors (RARs, RXRs), play a crucial role in cervix development and homeostasis regulating growth and differentiation of a wide variety of cell types; indeed, they can inhibit cell proliferation, and induce cell differentiation or apoptotic cell death. Here we introduce a mouse model that develops spontaneously malignant cervical lesions allowing the study of the cooperative effect between HPV16E6E7 expression and the lack of RXRα in cervical cancer development. This model could be useful to study multistep carcinogenesis of uterine cervix tissue and might improve chemopreventive and chemotherapeutic strategies for this neoplasia.  相似文献   
66.
PurposeTo compare dose to organs at risk (OARs) and biological evaluation using normal tissue complication probability (NTCP) for left-sided breast radiation therapy in 4 techniques: supine free breathing (SFB), supine deep inspiration breath hold (SDIBH), prone free breathing (PFB), and prone deep inspiration breath hold (PDIBH).Methods and MaterialsTwenty-five patients with left-sided breast cancer suitable for this study underwent a computed tomography scan using SFB, SDIBH, PFB, and PDIBH. One radiation oncologist contoured the planning target volume and OAR (cardiac components). Dose-volume histograms and NTCPs for the heart, left ventricle (LV), left anterior descending artery (LAD), and left lung were calculated for all 4 techniques.ResultsThe mean heart dose in PDIBH is 0.77 Gy, which is statistically significantly lower than in SFB (1.88 Gy, P < .0001), SDIBH (0.97 Gy, P < .001), and PFB (0.85 Gy, P < .001). The mean left lung dose is 0.69 Gy in PFB and 0.88 Gy in PDIBH. PFB and PDIBH have statistically significantly lower doses compared with SFB (6.09 Gy, P < .0001) and SDIBH (5.41 Gy, P < .0001). The mean NTCP in SFB for the heart, LV, and LAD is 0.27%, 0.62%, and 4.23%, respectively, and it is negligible for other techniques.ConclusionsWe found that PDIBH had a dosimetrically lower mean dose for the heart and LV compared with the other 3 techniques. In addition, SDIBH, PFB and PDIBH had statistically significantly lower NTCP for the heart, LV, and LAD compared with SFB. NTCP for the left lung was statistically significantly lower for prone techniques compared with supine techniques. Therefore we concluded that, compared with SDIBH, PDIBH provides the added benefit of sparing the heart while keeping the benefit of sparing the lung as in the prone technique.  相似文献   
67.
The purpose of this study is to examine the influence of Azone upon the skin target site free drug concentration (C(*)) and its correlation with the in vivo antiviral efficacies of cidofovir (HPMPC) and acyclovir (ACV) against HSV-1 infections. Formulations of HPMPC and ACV with or without Azone were used. The in vitro skin flux experiments were performed and the C(*) values were calculated. For the in vivo efficacy studies, hairless mice cutaneously infected with HSV-1 were used and three different treatment protocols were carried out. The protocols were chosen based upon when therapy is initiated and terminated in such a way to assess the efficacy of the test drug to cure and/or prevent HSV-1 infections. A finite dose of the formulation was topically applied twice a day for the predetermined time course for each protocol and the lesions were scored on the fifth day. For ACV formulation with Azone, the C(*) values and hence the in vivo efficacy were much higher than those for that without Azone. In protocol #1, however, early treatment did not increase the in vivo efficacy of ACV when compared with the standard treatment protocol #3. In protocol #2 where the treatment was terminated on the day of virus inoculation, the efficacies for both ACV formulations were completely absent. Although the estimated C(*) values for HPMPC formulations with and without Azone were comparable, formulation with Azone was much more effective than that without Azone in all treatment protocols. HPMPC formulations with Azone at similar flux values were much more effective in "treating and preventing" HSV-1 infections than those without Azone. For ACV formulations, in contrast, addition of Azone has failed to show any effect on the preventive in vivo antiviral efficacy and the enhancement of ACV in vivo antiviral efficacy was merely the skin permeation enhancement effect of Azone.  相似文献   
68.
PSD-95 binds to and co-localizes with NMDA receptors at postsynaptic sites. Their co-expression in COS7 cells induces the formation of aggregates containing both proteins. These findings have lead to the hypothesis that PSD-95 helps to cluster NMDA receptors at postsynaptic sites. In addition, PSD-95 binds various regulatory proteins including Src, Pyk2, SynGAP, and nNOS and may recruit signaling proteins to NMDA receptors. We tested whether synaptic transmission or plasticity was affected by acute dissociation of the PSD-95-NMDA receptor interaction with various peptides that bound to the first two PDZ domains of PSD-95 and its homologs and with antibodies directed against the very C-terminus of the NR2A and NR2B subunits of the NMDA receptor. Membrane-impermeable peptides injected via whole cell patch electrodes distributed within minutes throughout dendritic branches into spines in acute hippocampal slices and membrane-permeable peptides containing 11 arginine residues effectively accumulated in neurites in slices and primary hippocampal cultures. Neither peptides nor antibodies showed any effect on basal synaptic transmission or induction of long-term potentiation (LTP) in hippocampal slices. Pharmacologically isolated NMDA receptor activity was also not affected. However, the membrane-permeable peptide disrupted the NMDA receptor-PSD-95 interaction in slices as tested by immunoprecipitation and subsequent immunoblotting. These findings suggest that acute dissociation of PSD-95 and its homologs from the NMDA receptor and likely from other protein complexes does not result in any easily detectable physiological effects in hippocampal slices. However, we cannot exclude a role of PSD-95 in early events that lead to clustering of NMDA receptors or of other proteins including stargazin and AMPA receptors at postsynaptic sites nor do these experiments address the possibility of long-term changes in the slices. In fact, incubation of primary hippocampal cultures with the membrane-permeable peptide lead to a moderate decrease in the number of dendritic clusters of PSD-95 and NMDA receptors and their colocalization by 20-30%, suggesting some role of PSD-95 and its homologs in NMDA receptor clustering.  相似文献   
69.
70.
Folate content of human milk was determined in early transitional milk (4–7 days postpartum), transitional milk (10–14 days postpartum) and mature milk (36–45 days postpartum). Mature milk contained a mean total folate level of 4.9 μg/100 g. No diurnal variations were observed. At each stage, total folate was significantly higher (p<.05) than free folate. As lactation progressed to the mature milk stage, both free and total folate increased significantly (p<.05). The percentage of folate in the free form decreased as length of lactation increased. Based on folate levels determined in this study, a one month old breast-fed infant would have a folate intake of 6.7 μg/kg/day which is somewhat higher than the recommended dietary allowance for infants of 5 μg/kg/day.  相似文献   
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