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991.
Cadena EM Du X Gellerstedt G Li J Fillat A García-Ubasart J Vidal T Colom JF 《Bioresource technology》2011,102(4):3911-3917
Flax soda/AQ pulps were treated with different fungal laccase-mediator combinations followed by physical and chemical characterization of the pulps to obtain a thorough understanding of the laccase/mediator effects on hexenuronic acid (HexA) removal and the coupling of mediator onto pulps for fiber functionalization. Large differences were found and the presence of lauryl gallate (LG) during Trametes villosa laccase (TvL) treatment (TvL + LG) resulted in a much larger reduction of pulp-linked HexA than the combination of p-coumaric acid (PCA) and Pycnoporus cinnabarinus laccase (PcL). A major portion of LG became attached to the pulp as revealed by an increase in the kappa number and further confirmed by thioacidolysis and 1H NMR analysis of solubilized pulp fractions. Additional experiments with other chemical pulps and isolated pulp xylan and lignin revealed that HexA seems to be the sole pulp component attacked by TvL + LG. As a substrate for TvL, the reaction preference order is PCA > HexA > LG. 相似文献
992.
993.
As single agents, ABT-263 and ABT-737 (ABT), molecular antagonists of the Bcl-2 family, bind tightly to Bcl-2, Bcl-xL and Bcl-w, but not to Mcl-1, and induce apoptosis only in limited cell types. The compound 2-deoxyglucose (2DG), in contrast, partially blocks glycolysis, slowing cell growth but rarely causing cell death. Injected into an animal, 2DG accumulates predominantly in tumors but does not harm other tissues. However, when cells that were highly resistant to ABT were pre-treated with 2DG for 3 hours, ABT became a potent inducer of apoptosis, rapidly releasing cytochrome c from the mitochondria and activating caspases at submicromolar concentrations in a Bak/Bax-dependent manner. Bak is normally sequestered in complexes with Mcl-1 and Bcl-xL. 2DG primes cells by interfering with Bak-Mcl-1 association, making it easier for ABT to dissociate Bak from Bcl-xL, freeing Bak to induce apoptosis. A highly active glucose transporter and Bid, as an agent of the mitochondrial apoptotic signal amplification loop, are necessary for efficient apoptosis induction in this system. This combination treatment of cancer-bearing mice was very effective against tumor xenograft from hormone-independent highly metastasized chemo-resistant human prostate cancer cells, suggesting that the combination treatment may provide a safe and effective alternative to genotoxin-based cancer therapies. 相似文献
994.
995.
Introduction
Iodine is essential for normal fetal and neonatal development. We studied the prevalence and impact on fetal thyroid development of iodine deficiency in pregnant women in the northern part of the Paris conurbation.Materials and Methods
110 patients underwent several determinations of urinary iodine excretion (UIE) and of serum FT4, FT3, and TSH. Fetal thyroid gland size was assessed using ultrasonography.Results
We found evidence of widespread iodine deficiency (mean UIE, 49.8 µg/L [standard deviation, 2.11]). Iodine deficiency did not correlate significantly with maternal thyroid parameters but showed a significant negative correlation with fetal thyroid gland size (rho = 0.25, P = 0.02).Conclusion
Iodine deficiency during pregnancy is still a problem in our geographical area and affects the fetal thyroid gland.Clinical Trials.gov NCT00162539相似文献996.
Gómez-Marin JE de-la-Torre A Angel-Muller E Rubio J Arenas J Osorio E Nuñez L Pinzon L Mendez-Cordoba LC Bustos A de-la-Hoz I Silva P Beltran M Chacon L Marrugo M Manjarres C Baquero H Lora F Torres E Zuluaga OE Estrada M Moscote L Silva MT Rivera R Molina A Najera S Sanabria A Ramirez ML Alarcon C Restrepo N Falla A Rodriguez T Castaño G 《PLoS neglected tropical diseases》2011,5(5):e1195
Aims
To determine the incidence of congenital toxoplasmosis in Colombian newborns from 19 hospital or maternal child health services from seven different cities of five natural geographic regions (Caribbean, Central, Andean, Amazonia and Eastern).Materials and Methods
We collected 15,333 samples from umbilical cord blood between the period of March 2009 to May 2010 in 19 different hospitals and maternal-child health services from seven different cities. We applied an IgM ELISA assay (Vircell, Spain) to determine the frequency of IgM anti Toxoplasma. The results in blood cord samples were confirmed either by western blot and repeated ELISA IgM assay. In a sub-sample of 1,613 children that were negative by the anti-Toxoplasma IgM assay, the frequency of specific anti-Toxoplasma IgA by the ISAGA assay was determined. All children with positive samples by IgM, IgA, clinical diagnosis or treatment during pregnancy were recalled for confirmatory tests after day 10 of life.Results
61 positive samples for specific IgM (0.39%) and 9 positives for IgA (0.5%) were found. 143 questionnaires were positive for a clinical diagnosis or treatment for toxoplasmosis during pregnancy. 109 out of the 218 children that had some of the criteria for postnatal confirmatory tests were followed. Congenital toxoplasmosis infection was confirmed in 15 children: 7 were symptomatic, and three of them died before the first month of life (20% of lethality). A significant correlation was found between a high incidence of markers for congenital toxoplasmosis and higher mean annual rainfall for the city.Conclusions
Incidence for congenital toxoplasmosis is significantly different between hospitals or maternal child health services from different cities in Colombia. Mean annual rainfall was correlated with incidence of congenital toxoplasmosis. 相似文献997.
998.
999.
The mitochondrial T16189C polymorphism is associated with coronary artery disease in Middle European populations 总被引:1,自引:0,他引:1
Mueller EE Eder W Ebner S Schwaiger E Santic D Kreindl T Stanger O Paulweber B Iglseder B Oberkofler H Maier R Mayr JA Krempler F Weitgasser R Patsch W Sperl W Kofler B 《PloS one》2011,6(1):e16455
Background
The pivotal role of mitochondria in energy production and free radical generation suggests that the mitochondrial genome could have an important influence on the expression of multifactorial age related diseases. Substitution of T to C at nucleotide position 16189 in the hypervariable D-loop of the control region (CR) of mitochondrial DNA (mtDNA) has attracted research interest because of its suspected association with various multifactorial diseases. The aim of the present study was to compare the frequency of this polymorphism in the CR of mtDNA in patients with coronary artery disease (CAD, n = 482) and type 2 diabetes mellitus (T2DM, n = 505) from two study centers, with healthy individuals (n = 1481) of Middle European descent in Austria.Methodology and Principal Findings
CR polymorphisms and the nine major European haplogroups were identified by DNA sequencing and primer extension analysis, respectively. Frequencies and Odds Ratios for the association between cases and controls were calculated. Compared to healthy controls, the prevalence of T16189C was significantly higher in patients with CAD (11.8% vs 21.6%), as well as in patients with T2DM (11.8% vs 19.4%). The association of CAD, but not the one of T2DM, with T16189C remained highly significant after correction for age, sex and body mass index (BMI) and was independent of the two study centers.Conclusions and Significance
Our results show for the first time a significant association of T16189C with CAD in a Middle European population. As reported in other studies, in patients with T2DM an association with T16189C in individuals of European decent remains questionable. 相似文献1000.