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61.
Kirsti A Bocskay Deliang Tang Manuela A Orjuela Xinhua Liu Dorothy P Warburton Frederica P Perera 《Cancer epidemiology, biomarkers & prevention》2005,14(2):506-511
Molecular and traditional epidemiology studies have indicated a possible relationship between in utero environmental exposures and increased risk for childhood cancers, especially acute leukemias. Chromosomal aberrations have been associated with environmental exposures and cancer risk in adults. In order to more clearly define the association between prenatal exposures to carcinogenic polycyclic aromatic hydrocarbons (PAH) and chromosomal aberrations, chromosomal aberration frequencies were measured in a subset of 60 newborns from the Columbia Center for Children's Environmental Health (CCCEH) Prospective Cohort Study. The subset was composed of African American and Dominican, nonsmoking mother-newborn pairs residing in low-income neighborhoods of New York City, who were exposed to varying levels of airborne PAHs. Prenatal exposure was assessed by questionnaire, personal air monitoring during the third trimester, and PAH-DNA adducts in umbilical cord blood. Chromosomal aberrations were measured in cord blood lymphocytes by fluorescence in situ hybridization. PAH-DNA adducts were not associated with chromosomal aberrations. However, airborne PAHs were significantly associated with stable aberration frequencies in cord blood (P < 0.01). Moreover, stable aberration frequencies were significantly higher among African American newborns compared with Dominican, despite no significant differences in PAH exposure. These results show for the first time an association between prenatal exposure to airborne carcinogenic PAHs and chromosomal aberrations in cord blood, suggesting that such prenatal exposures have the potential to cause cytogenetic damage that has been related to increased cancer risk in other populations. If confirmed, this finding may open new avenues for prevention. 相似文献
62.
63.
Gabriela Datsch Bennemann Emilia Addison Machado Moreira Leticia Cristina Radin Pereira Maiara Brusco de Freitas Diane de Oliveira Julia Carvalho Ventura Eduardo Benedetti Parisotto Yara Maria Franco Moreno Erasmo Benicio Santos Moraes Trindade Eliana Barbosa Norberto Ludwig Neto Danilo Wilhelm Filho 《The clinical respiratory journal》2022,16(6):475
IntroductionOxidative stress (OS) occurs in cystic fibrosis (CF).ObjectiveThe objective of this work is to evaluate the influence of bacterial infection on biomarkers of OS (catalase [CAT], glutathione peroxidade [GPx], reduced glutathione [GSH]), markers of oxidative damage (protein carbonyls [PC], thiobarbituric acid reactive substances [TBARS]), together with the nutritional status and lung function in children with CF.MethodsCross‐sectional study including CF group (CFG, n = 55) and control group (CG, n = 31), median age: 3.89 and 4.62 years, respectively. CFG was distributed into CFG negative bacteriology (CFGB−, n = 27) or CFG positive bacteriology (CFGB+, n = 28), and CFG negative Pseudomonas aeruginosa (CFGPa−, n = 36) or CFG positive Pseudomonas aeruginosa (CFGPa+, n = 19).ResultsCompared with CG, CFG (P = .034) and CFGB+ (P = .042) had lower body mass index‐for‐age z‐score; forced expiratory volume in the first second was lower in CFGB+ and CFGPa+ (both P < .001). After adjusting for confounders and compared with CG: CFG showed higher TBARS (P ≤ .001) and PC (P = .048), and lower CAT (P = .004) and GPx (P = .003); the increase in PC levels was observed in CFGB+ (P = .011) and CFGPa+ (P = .001) but not in CFGB− (P = .510) and CFGPa− (P = .460).ConclusionsThese results indicate a systemic OS in children with CF. The presence of bacterial infection particularly Pseudomonas aeruginosa seems to be determinant to exacerbate the oxidative damage to proteins, in which PC may be a useful biomarker of OS in CF. 相似文献
64.
Stefan Pleus Andreas Stuhr Manuela Link Cornelia Haug Guido Freckmann 《Journal of diabetes science and technology》2022,16(3):649
Background:There is an increasing use of continuous glucose monitoring (CGM) by people with diabetes. Measurement performance is often characterized by the mean absolute relative difference (MARD). However, MARD is influenced by a number of factors and little is known about whether MARD is stable throughout the day.Material and Methods:A total of 24 participants with type 1 diabetes were enrolled in the study. The study was performed for seven in-patient days. Participants wore two CGM systems in parallel and performed additional frequent blood glucose (BG) measurements. On two days, glucose excursions were induced.MARD was calculated between pairs of CGM and BG values, with BG values serving as reference values. ARD values calculated from CGM-BG pairs were grouped by hour of the day. Results were analyzed separately for glucose excursion days and for regular days.Results:Total MARDs for the complete study duration were 12.5% ± 3.6% and 13.2% ± 2.4% (n = 24). Throughout the day marked variability of MARD was observed (8.0% ± 1.3%-16.3% ± 2.9% (G5); 9.1% ± 1.4%-16.3% ± 5.3% (FL), up to n = 157 each). Low(est) MARD values were observed before breakfast and dinner, when subjects were in or near a fasting state. Especially after breakfast and lunch, MARD values were higher than average.Conclusions:Analytical performance of the two CGM systems, assessed by MARD, was found to vary markedly throughout the day. Activities of daily life likely triggered these variations. An increasing number of CGM users base therapeutic decisions on CGM values, and they should be aware of these variations of performance throughout the day. 相似文献
65.
66.
U. Zanelli P. Puccini D. Acerbi P. Ventura P. G. Gervasi 《Archives of toxicology》1996,70(3-4):145-149
The influence of pivalic acid (PIV), a compound often used to make pro-drugs, and of the structurally related trichloroacetic
acid (TCA), on several hepatic and renal enzymes was investigated in Sprague-Dawley rats, following a 4-day treatment period.
The PIV and TCA treatments resulted in a similar and selective induction (2 – 3 times) of peroxisomal palmitoyl-CoA oxidase
and the cytochrome P-450 4A dependent microsomal (ω)- and (ω-1)-lauric acid activities, both in liver and kidney. Western
blot analysis of liver and kidney microsomes from PIV- and TCA-treated rats, using antibody to the P-450 4A1, revealed induction
of members of the P-450 4A subfamily. These results suggest that PIV, like TCA, is a renal and hepatic peroxisome proliferator
in rats, and further support the previously indicated close association between the peroxisomal fatty acid β-oxidation enzymes
and microsomal P-450 4A subfamily enzymes.
Received: 7 February 1995 / Accepted: 21 August 1995 相似文献
67.
Nehal Elkhoshkhany Samir Marzouk Mohammed El-Sherbiny Heba Ibrahim Bozena Burtan-Gwizdala Mohammed S. Alqahtani Khalid I. Hussien Manuela Reben El Sayed Yousef 《Materials》2022,15(15)
A novel series of glass, consisting of B2O3, Bi2O3, TeO2, and TiO2 (BBTT) containing rare earth oxide RE2O3, where RE is La, Ce, Sm, Er, and Yb, was prepared. We investigated the structural, optical, and gamma attenuation properties of the resultant glass. The optical energy bands, the linear refractive indices, the molar refractions, the metallization criteria, and the optical basicity were all determined for the prepared glass. Furthermore, physical parameters such as the density, the molar volume, the oxygen molar volume, and the oxygen packing density of the prepared glass, were computed. Both the values of density and optical energy of the prepared glass increased in the order of La2O3, Ce2O3, Sm2O3, Er2O3, and then Yb2O3. In addition, the glass doped with Yb2O3 had the lowest refractive index, electronic polarizability, and optical basicity values compared with the other prepared glass. The structures of the prepared glass were investigated by the deconvolution of infrared spectroscopy, which determined that TeO4, TeO3, BO4, BO3, BiO6, and TiO4 units had formed. Furthermore, the structural changes in glass are related to the ratio of the intensity of TeO4/TeO3, depending on the type of rare earth. It is also clarified that the resultant glass samples are good attenuators against low-energy radiation, especially those that modified by Yb2O3, which exhibited superior shielding efficiency at energies of 622, 1170, and 1330 keV. The optical and gamma ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optical fibers, laser solid material, and optical shielding protection. 相似文献
68.
A fluorescent curcumin-based Zn(II)-complex reactivates mutant (R175H and R273H) p53 in cancer cells
Alessia Garufi Daniela Trisciuoglio Manuela Porru Carlo Leonetti Antonella Stoppacciaro Valerio D’Orazi Maria Laura Avantaggiati Alessandra Crispini Daniela Pucci Gabriella D’Orazi 《Journal of experimental & clinical cancer research : CR》2013,32(1):72
Background
Mutations of the p53 oncosuppressor gene are amongst the most frequent aberration seen in human cancer. Some mutant (mt) p53 proteins are prone to loss of Zn(II) ion that is bound to the wild-type (wt) core, promoting protein aggregation and therefore unfolding. Misfolded p53 protein conformation impairs wtp53-DNA binding and transactivation activities, favouring tumor growth and resistance to antitumor therapies. Screening studies, devoted to identify small molecules that reactivate mtp53, represent therefore an attractive anti-cancer therapeutic strategy. Here we tested a novel fluorescent curcumin-based Zn(II)-complex (Zn-curc) to evaluate its effect on mtp53 reactivation in cancer cells.Methods
P53 protein conformation was examined after Zn-curc treatment by immunoprecipitation and immunofluorescence assays, using conformation-specific antibodies. The mtp53 reactivation was evaluated by chromatin-immunoprecipitation (ChIP) and semi-quantitative RT-PCR analyses of wild-type p53 target genes. The intratumoral Zn-curc localization was evaluated by immunofluorescence analysis of glioblastoma tissues of an ortothopic mice model.Results
The Zn-curc complex induced conformational change in p53-R175H and -R273H mutant proteins, two of the most common p53 mutations. Zn-curc treatment restored wtp53-DNA binding and transactivation functions and induced apoptotic cell death. In vivo studies showed that the Zn-curc complex reached glioblastoma tissues of an ortothopic mice model, highlighting its ability to crossed the blood-tumor barrier.Conclusions
Our results demonstrate that Zn-curc complex may reactivate specific mtp53 proteins and that may cross the blood-tumor barrier, becoming a promising compound for the development of drugs to halt tumor growth. 相似文献69.
A total of 3179 patients were screened for Y-chromosome microdeletions and 821 patients for partial AZFc deletions. Thirty-nine Y-chromosomal microdeletions were found (2.4% of men with <1 x 10(6)/ml spermatozoa): two AZFa, two AZFb, one AZFbc, one partial AZFb, one partial AZFb+c and 32 AZFc (b2/b4). Partial AZFc deletions were found in 45 patients (5.5%), mostly gr/gr deletions (n = 28). In patients with AZFc deletion, azoospermia was found in 53.1% and sperm concentrations of mostly <0.1 x 10(6)/ml were found in 46.9%. Semen analyses and FSH measurements showed no trend over time. Elongated spermatids were seen in 6/15 AZFc patients and bilateral Sertoli cell-only was found in 4/15. Testicular sperm extraction (TESE) was attempted in 10 patients and spermatozoa were found in six. Compared with infertile men matched by sperm concentration, no differences in hormonal and seminal parameters could be found in patients with AZFc or gr/gr deletions. It is concluded that: (i) frequency of AZF deletions in Germany is much lower than in other countries; (ii) AZFc deletions are associated with severe disturbances of spermatogenesis and TESE is not possible in half of these patients; (iii) AZFc and gr/ gr deletions are not associated with any clinical diagnostic parameter; (iv) and no trend is apparent over time. 相似文献
70.
Pérez G C Zavala S MA Ventura R E Pérez G S Ponce M H 《Journal of ethnopharmacology》2008,120(2):138-140