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83.
Gilad Twig Estela Derazne Ziona Haklai Nehama Goldberger Arnon Afek Hertzel C. Gerstein Jeremy D. Kark Tali Cukierman-Yaffe 《Cardiovascular diabetology》2018,17(1):154
Background
Epidemiological studies have demonstrated a relationship between cognitive function in youth and the future risk of death. Less is known regarding the relationship with diabetes related death. This study assessed the relationship between cognitive function in late adolescence and the risk for diabetes, cardiovascular- (CVD) and all-cause mortality in adulthood.Methods
This retrospective study linked data from 2,277,188 16–19 year olds who had general intelligence tests (GIT) conducted during pre-military recruitment assessment with cause of death as coded by the Israel Central Bureau of Statistics. The associations between cognitive function and cause-specific mortality were assessed using Cox models.Results
There were 31,268 deaths that were recorded during 41,916,603 person-years of follow-up, with a median follow-up of 19.2 (IQR 10.7, 29.5) years. 3068, 1443, 514 and 457 deaths were attributed to CVD, CHD, stroke, and diabetes, respectively. Individuals in the lowest GIT vs. highest GIT quintiles in unadjusted models had the highest risk for all-cause mortality (HR 1.84, 95% CI 1.78, 1.91), total CVD (HR 3.32, 95% CI 2.93, 3.75), CHD (HR 3.49 95% CI 2.92, 4.18), stroke (HR 3.96 95% CI 2.85, 5.5) and diabetes-related (HR 6.96 95% CI 4.68, 10.36) mortality. These HRs were attenuated following adjustment for age, sex, birth year, body-mass index, residential socioeconomic status, education and country of origin for all-cause (HR 1.23, 95% CI 1.17, 1.28), CVD (HR 1.76, 95% CI 1.52, 2.04), CHD (HR 1.7 95% CI 1.37, 2.11), stroke (HR 2.03, 95% CI 1.39, 2.98) and diabetes-related (HR 3.14 95% CI 2.00, 4.94) mortality. Results persisted in a sensitivity analyses limited to participants with unimpaired health at baseline and that accounted competing risk.Conclusions
This analysis of over 2 million demonstrates a strong relationship between cognitive function at youth and the risk for diabetes, all-cause and CVD-related mortality independent of adolescent obesity.84.
Giulio Kleiner Emanuele Barca Marcello Ziosi Valentina Emmanuele Yimeng Xu Agustin Hidalgo-Gutierrez Changhong Qiao Saba Tadesse Estela Area-Gomez Luis C. Lopez Catarina M. Quinzii 《生物化学与生物物理学报:疾病的分子基础》2018,1864(11):3708-3722
Nephrotic syndrome (NS), a frequent chronic kidney disease in children and young adults, is the most common phenotype associated with primary coenzyme Q10 (CoQ10) deficiency and is very responsive to CoQ10 supplementation, although the pathomechanism is not clear. Here, using a mouse model of CoQ deficiency-associated NS, we show that long-term oral CoQ10 supplementation prevents kidney failure by rescuing defects of sulfides oxidation and ameliorating oxidative stress, despite only incomplete normalization of kidney CoQ levels and lack of rescue of CoQ-dependent respiratory enzymes activities. Liver and kidney lipidomics, and urine metabolomics analyses, did not show CoQ metabolites. To further demonstrate that sulfides metabolism defects cause oxidative stress in CoQ deficiency, we show that silencing of sulfide quinone oxido-reductase (SQOR) in wild-type HeLa cells leads to similar increases of reactive oxygen species (ROS) observed in HeLa cells depleted of the CoQ biosynthesis regulatory protein COQ8A. While CoQ10 supplementation of COQ8A depleted cells decreases ROS and increases SQOR protein levels, knock-down of SQOR prevents CoQ10 antioxidant effects. We conclude that kidney failure in CoQ deficiency-associated NS is caused by oxidative stress mediated by impaired sulfides oxidation and propose that CoQ supplementation does not significantly increase the kidney pool of CoQ bound to the respiratory supercomplexes, but rather enhances the free pool of CoQ, which stabilizes SQOR protein levels rescuing oxidative stress. 相似文献
85.
María Cabello‐Donayre Sophie Malagarie‐Cazenave Jenny Campos‐Salinas Francisco J. Gálvez Alba Rodríguez‐Martínez Estela Pineda‐Molina Lina M. Orrego Marta Martínez‐García María P. Sánchez‐Cañete Antonio M. Estévez José M. Pérez‐Victoria 《Molecular microbiology》2016,101(6):895-908
Pathogenic trypanosomatid parasites are auxotrophic for heme and they must scavenge it from their human host. Trypanosoma brucei (responsible for sleeping sickness) and Leishmania (leishmaniasis) can fulfill heme requirement by receptor‐mediated endocytosis of host hemoglobin. However, the mechanism used to transfer hemoglobin‐derived heme from the lysosome to the cytosol remains unknown. Here we provide strong evidence that HRG transporters mediate this essential step. In bloodstream T. brucei, TbHRG localizes to the endolysosomal compartment where endocytosed hemoglobin is known to be trafficked. TbHRG overexpression increases cytosolic heme levels whereas its downregulation is lethal for the parasites unless they express the Leishmania orthologue LmHR1. LmHR1, known to be an essential plasma membrane protein responsible for the uptake of free heme in Leishmania, is also present in its acidic compartments which colocalize with endocytosed hemoglobin. Moreover, LmHR1 levels modulated by its overexpression or the abrogation of an LmHR1 allele correlate with the mitochondrial bioavailability of heme from lysosomal hemoglobin. In addition, using heme auxotrophic yeasts we show that TbHRG and LmHR1 transport hemoglobin‐derived heme from the digestive vacuole to the cytosol. Collectively, these results show that trypanosomatid parasites rescue heme from endocytosed hemoglobin through endolysosomal HRG transporters, which could constitute novel drug targets. 相似文献
86.
Claudia Etchebehere Elena Castelló Jorge Wenzel Mélida del Pilar Anzola-Rojas Liliana Borzacconi Germán Buitrón Lea Cabrol Vivian María Carminato Julian Carrillo-Reyes Crhistian Cisneros-Pérez Laura Fuentes Iván Moreno-Andrade Elías Razo-Flores Gonzalo Ruiz Filippi Estela Tapia-Venegas Javiera Toledo-Alarcón Marcelo Zaiat 《Applied microbiology and biotechnology》2016,100(7):3371-3384
87.
The present paper reports an improvement to the classical method of the paraffin bait, by the usage of 1 M NH4Cl or 2 M NaCl to eliminate contaminant microflora of soil.The purpose is to introduce a change in the paraffin bait method in order to reduce time required to isolate pathogenic strains of Nocardia from their natural sources.For this study three main criteria were used: a) Determination of the inhibitory effect of different concentrations of salts on soil microflora; b) The tolerance of Nocardia brasiliensis, Nocardia asteroides and Nocardia caviae (Nocardia otitidis caviarum) strains to these chemical inhibitors; c) Determination of the efficiency of salts in the isolation of Nocardia from soil when strains are grown on paraffin baits. 相似文献
88.
Estela E. Medrano Sara H. Goldemberg I. D. Algranati 《Journal of cellular physiology》1983,117(2):141-147
In order to study the effect of polyamine depletion on growth and proliferation of untransformed and chemically transformed cells, α-difluoromethyl-ornithine (DFMO) was added to cultures of 3T3 cells and their benzo[a]pyrene derivative BP-3T3. Both types of cells stopped their proliferation after 72 hr of treatment with the inhibitor. When DFMO was removed and cells were cultivated afterwards in fresh medium without the drug, untransformed cells resumed growth after a lag period, whereas transformed cells were unable to proliferate unless exogenous polyamine was added. These alterations showed a strict correlation with intracellular polyamine pools, since after removal of DFMO from the culture medium, polyamine concentrations increased to almost normal values in 3T3 cells, but remained at low levels or decreased even more in the transformed cells BP-3T3. The analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of labeled proteins of both cell extracts has indicated that the described control of cell proliferation by intracellular polyamine levels might be related to the synthesis of at least two proteins with molecular weights of about 36,000 and 55,000 daltons. 相似文献
89.
Amino acid pools were analyzed in maize (Zea mays L.) axes germinated for 0, 6 and 24 h. Proteins synthesized at early (0–6 h) and late (18–24 h) stages were characterized by gel electrophoresis and fluorography after either 14C-leucine or 14C-lysine pulses. An increase of amino acid incorporation after 18–24 h was observed, as well as changes in the protein patterns of the corresponding fluorographs. Analysis of the endogenous amino acid pools showed major changes in contents of proline, alanine, isoleucine, valine, leucine and lysine. A selective increase of lysine incorporation into proteins during the late stage was detected.Under the Academic Colaboration Program between the Universidad Nacional Autónoma de México and the Colegio de Postgraduados, Chapingo, México. 相似文献
90.
Species of Gracilaria are some of the most useful algae in the world for the production of agar. As a consequence of its economic importance, the
genus has been the subject of many studies worldwide. Color variants of Gracilaria birdiae have been found in the natural population on the Brazilian coast, and they have also been isolated from plants cultivated
in laboratory. These findings raised new questions regarding intraspecific variation and the prospects of cultivating such
variants for their agar production. Therefore, this work aimed to determine the mode of color inheritance for two G. birdiae strains: a greenish-brown strain (gb) found in a natural population and a green strain (gr) which had arisen as a spontaneous
mutation in a red plant cultured in the laboratory. The pigment contents of these strains, as well as the red wild-type (rd),
were also characterized. Crosses between female and male plants of the same color (rd, gr, or gb) and between different colors
were performed. Crosses between plants of the same color showed tetrasporophytic and gametophytic descendents of the parental
color. Recessive nuclear inheritance was found in the greenish-brown strain, and cytoplasmic maternal inheritance was found
in the green strain; both had lower phycoerythrin and higher concentrations of allophycocyanin and phycocyanin than the wild-type.
Chlorophyll a contents were similar among all strains. Taken together, our results contribute to knowledge about the variability of this
important red algae. In addition, since greenish-brown and green strains showed stability of color, both could be selected
and tested in experimental sea cultivation to evaluate if mutants have advantageous performance when compared with red strain. 相似文献