448 research outputs found
Interaction Between Marginal Zinc and High Fat Supply on Lipid Metabolism and Growth of Weanling Rats
The impact of a moderate Zn deficiency on growth and plasma and liver lipids was investigated in two 4-week experiments with male weanling rats fed fat-enriched diets. Semisynthetic, approximately isocaloric diets containing 3% soybean oil were supplemented with either 7 or 100 mg Zn/kg diet and with 22% beef tallow (BT) or sunflower oil (SF). In Experiment 1, which compared the dietary fat level and the fat source in a factorial design of treatments, all diets were fed ad libitum to 6 × 8 animals, whereas intake of the high-Zn BT and SF diets was restricted in Experiment 2 (5 × 6 rats) to the level of intake of the respective low-Zn diets. The low-Zn SF diet consistently depressed food intake and final live weights of the animals to a greater extent than the other low-Zn diets, while intake and growth were comparable among the animals fed the high-Zn diets. The marginal Zn deficit per se did not alter plasma triglyceride and cholesterol concentrations nor hepatic concentrations of triglyceride, cholesterol and phospholipids. The fatty acid pattern of liver phospholipids did not indicate that chain elongation and desaturation of fatty acids was impaired by a lack of zinc. It was concluded that dietary energy and fat intake, and fat source have a greater effect on plasma and liver lipids than a moderate Zn deficiency. Marginally Zn-deficient diets enriched with sunflower oil as a major energy source cause a greater growth retardation than diets rich in carbohydrates or beef tallow
Enzymatic properties of the Caenorhabditis elegans Dna2 endonuclease/helicase and a species-specific interaction between RPA and Dna2
In both budding and fission yeasts, a null mutation of the DNA2 gene is lethal. In contrast, a null mutation of Caenorhabditis elegans dna2(+) causes a delayed lethality, allowing survival of some mutant C.elegans adults to F2 generation. In order to understand reasons for this difference in requirement of Dna2 between these organisms, we examined the enzymatic properties of the recombinant C.elegans Dna2 (CeDna2) and its interaction with replication-protein A (RPA) from various sources. Like budding yeast Dna2, CeDna2 possesses DNA-dependent ATPase, helicase and endonuclease activities. The specific activities of both ATPase and endonuclease activities of the CeDna2 were considerably higher than the yeast Dna2 (∼10- and 20-fold, respectively). CeDna2 endonuclease efficiently degraded a short 5′ single-stranded DNA tail (<10 nt) that was hardly cleaved by ScDna2. Both endonuclease and helicase activities of CeDna2 were stimulated by CeRPA, but not by human or yeast RPA, demonstrating a species-specific interaction between Dna2 and RPA. These and other enzymatic properties of CeDna2 described in this paper may shed light on the observation that C.elegans is less stringently dependent on Dna2 for its viability than Saccharomyces cerevisiae. We propose that flaps generated by DNA polymerase δ-mediated displacement DNA synthesis are mostly short in C.elegans eukaryotes, and hence less dependent on Dna2 for viability
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Replication and Meta-analysis of the Association between BDNF Val66Met Polymorphism and Cognitive Impairment in Patients Receiving Chemotherapy.
Cancer-related cognitive impairment (CRCI) adversely affects cancer patients. We had previously demonstrated that the BDNF Val66Met genetic polymorphism is associated with lower odds of subjective CRCI in the multitasking and verbal ability domains among breast cancer patients receiving chemotherapy. To further assess our previous findings, we evaluated the association of BDNF Val66Met polymorphism with subjective and objective CRCI in a temporally separate cohort of patients and pooled findings from both the original (n = 145) and current (n = 193) cohorts in a meta-analysis. Subjective CRCI was assessed using FACT-Cog. Objective CRCI was evaluated using computerized neuropsychological tests. Genotyping was carried out using Sanger sequencing. The association of BDNF Val66Met genotypes and CRCI was examined with logistic regression. A fixed-effect meta-analysis was conducted using the inverse variance method. In the meta-analysis (n = 338), significantly lower odds of CRCI were associated with Met allele carriers based on the global FACT-Cog score (OR = 0.52, 95% CI 0.29-0.94). Furthermore, Met allele carriers were at lower odds of developing impairment in the domains of memory (OR = 0.34, 95% CI: 0.17-0.70), multitasking (OR = 0.33, 95% CI: 0.18-0.59), and verbal ability (OR = 0.46, 95% CI: 0.24-0.88). Consistent with the previous study, lower odds of subjective CRCI among patients with the BDNF Met allele was observed after adjusting for potential confounders in the multitasking (OR = 0.30, 95% CI: 0.14-0.67) domain. In conclusion, carriers of the BDNF Met allele were protected against global subjective CRCI, particularly in the domains of memory, multitasking, and verbal ability. Our findings further contribute to the understanding of CRCI pathophysiology
Spin-polarized quasiparticle injection effects in YBCO thin films
We report detailed transport studies on ferromagnet-superconductor
heterostructures. Epitaxial heterostructures of half-metal colossal
magnetoresistive La2/3Ca1/3MnO3 (HM-CMR) and high Tc superconducting YBa2Cu3O7
(YBCO) are grown on SrTiO3 (100) single crystal substrates by pulsed laser
deposition. Using the HM--CMR layer as source for spin-polarized
quasiparticles, we show the effect of injection of spin-polarized
quasiparticles into the ab-plane and along the c-axis of YBCO. The results show
a drop in the ab-plane resistance Rab (T) in the case of injection along the
c-axis that is discussed to be related to the opening of a pseudogap.Comment: 6 pages, 2 figure
Clinical Significance of Age at the Time of Diagnosis among Young Breast Cancer Patients
PURPOSE: The aims of this study were to investigate outcomes corresponding to age at diagnosis as categorized into 5-year intervals and to explore whether endocrine-responsive tumors display clinical benefits from endocrine therapy after chemotherapy among young breast cancer patients.
METHODS: A total of 1,171 patients who were under 40 years old at diagnosis between 1985 and 2007 were divided into 3 subgroups: ≤30 years (Group I, 13.3%), 31-35 years (Group II, 30.5%), and 36-40 years (Control group, 56.2%). Clinicopathological factors and outcomes were compared using a chi-square test, the Kaplan-Meier method, and Cox's hazards models.
RESULTS: There were no significant differences in the characteristics and treatment patterns between the 3 groups, except for the grade, hormone receptors expression, and use of endocrine therap. Group I showed the worst survival and subsequently Group II presented worse outcomes than the Control group, mainly among hormone receptors-positive patients. Groups I and II showed increased risks of recurrence and death in multivariate analyses. Among 529 hormone receptors-positive patients who received chemotherapy, favorable outcomes for patients who were treated with endocrine agents were demonstrated, mainly in patients aged 35 years or less. However, interaction tests between the use of endocrine therapy and age at diagnosis were not significant.
CONCLUSION: Age at diagnosis is an independent prognostic factor and the age of 35 years is a rational cut-off among young patients. Our subgroup analysis suggests that endocrine therapy may provide additional benefits even in young breast cancers. Therefore, further researches should be directed towards improving outcomes for this population.ope
Overexpression of hepatic serum amyloid A1 in mice increases IL-17-producing innate immune cells and decreases bone density
Serum amyloid A (SAA) is an acute-phase protein produced primarily in the liver that plays a key role in both the initiation and maintenance of inflammation. Rapidly secreted SAA induces neutrophilia at inflammatory sites, initiating inflammation and inducing the secretion of various cytokines, including TNF-α, IL-6, and IL-17. IL-17 is expressed in several inflammatory cells, including innate immune cells such as γδT cells, ILC3 cells, and neutrophils. Increased IL-17 levels exacerbate various inflammatory diseases. Among other roles, IL-17 induces bone loss by increasing receptor activator of nuclear factor-κB ligand (RANKL) secretion, which stimulates osteoclast differentiation. Several studies have demonstrated that chronic inflammation induces bone loss, suggesting a role for SAA in bone health. To test this possibility, we observed an increase in IL-17-producing innate immune cells, neutrophils, and γδT cells in these mice. In 6-month-old animals, we detected increased osteoclast-related gene expression and IL- 17 expression in bone lysates. We also observed an increase in neutrophils that secreted RANKL in the bone marrow of TG mice. Finally, we demonstrated decreased bone mineral density in these transgenic (TG) mice. Our results revealed that the TG mice have increased populations of IL-17-producing innate immune cells, γδT cells, and neutrophils in TG mice. We additionally detected increased RANKL and IL-17 expression in the bone marrow of 6-month-old TG mice. Furthermore, we confirmed significant increases in RANKL-expressing neutrophils in TG mice and decreased bone mineral density. Our results provide evidence that chronic inflammation induced by SAA1 causes bone loss via IL-17-secreting innate immune cells. © 2021 American Society for Biochemistry and Molecular Biology Inc.. All rights reserved.1
Safety and Efficacy of Second-Generation Everolimus-Eluting Xience V Stents Versus Zotarolimus-Eluting Resolute Stents in Real-World Practice Patient-Related and Stent-Related Outcomes From the Multicenter Prospective EXCELLENT and RESOLUTE-Korea Registries
ObjectivesThis study sought to compare the safety and efficacy of the Xience V/Promus everolimus-eluting stent (EES) (Abbott Vascular, Temecula, California) with the Endeavor Resolute zotarolimus-eluting stent (ZES-R) (Medtronic Cardiovascular, Santa Rosa, California) in “all-comer” cohorts.BackgroundOnly 2 randomized controlled trials have compared these stents.MethodsThe EXCELLENT (Efficacy of Xience/Promus Versus Cypher to Reduce Late Loss After Stenting) and RESOLUTE-Korea registries prospectively enrolled 3,056 patients treated with the EES and 1,998 patients treated with the ZES-R, respectively, without exclusions. Stent-related composite outcomes (target lesion failure [TLF]) and patient-related composite outcomes were compared in crude and propensity score-matched analyses.ResultsOf 5,054 patients, 3,830 (75.8%) had off-label indication (2,217 treated with EES and 1,613 treated with ZES-R). The stent-related outcome (82 [2.7%] vs. 58 [2.9%], p = 0.662) and the patient-related outcome (225 [7.4%] vs. 153 [7.7%], p = 0.702) did not differ between EES and ZES-R, respectively, at 1 year, which was corroborated by similar results from the propensity score-matched cohort. The rate of definite or probable stent thrombosis (18 [0.6%] vs. 7 [0.4%], p = 0.306) also was similar. In multivariate analysis, off-label indication was the strongest predictor of TLF (adjusted hazard ratio: 2.882; 95% confidence interval: 1.226 to 6.779; p = 0.015).ConclusionsIn this robust real-world registry with unrestricted use of EES and ZES-R, both stents showed comparable safety and efficacy at 1-year follow-up. Overall incidences of TLF and definite stent thrombosis were low, even in the patients with off-label indication, suggesting excellent safety and efficacy of both types of second-generation drug-eluting stents
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