排序方式: 共有111条查询结果,搜索用时 15 毫秒
41.
Martinez-Finley EJ Avila DS Chakraborty S Aschner M 《Metallomics : integrated biometal science》2011,3(3):271-279
Neurodegeneration is characterized by the cell death or loss of structure and/or function of neurons. Many neurodegenerative diseases including Parkinson's disease (PD) and Alzheimer's disease (AD) are the result of neurodegenerative processes. Metals are essential for many life processes, but they are also culpable for several neurodegenerative mechanisms. In this review, we discuss the role of metals in neurodegenerative diseases with emphasis on the utility of Caenorhabditis elegans (C. elegans) genetic models in deciphering mechanisms associated with the etiology of PD and AD. 相似文献
42.
da Silva Araujo Daiana Sousa Brasil Leandro Schlemmer Pozzobom Ully Mattilde de Azevêdo Carlos Augusto Silva Lima Lucas Ramos Costa 《Limnology》2023,24(3):161-169
Limnology - In-stream conditions can affect the distribution of the Ephemeroptera, Plecoptera, and Trichoptera orders (EPT) because they require specific food resources and good quality water.... 相似文献
43.
Daiana K. Garcez Crislaine Barbosa Marcelo Loureiro Matheus V. Volcan Daniel Loebmann Fernando M. Quintela Lizandra J. Robe 《Environmental Biology of Fishes》2018,101(10):1503-1515
Austrolebias wolterstorffi is a critically endangered annual fish, occurring in temporary ponds in a restricted area of Southern Brazil and Uruguay. Here, we evaluate the levels of genetic diversity and morphometric differentiation presented by A. wolterstorffi, attempting to reconstruct the spatiotemporal scenario by which this species reached their current distribution. Part of the mitochondrial cytochrome b and nuclear rhodopsin genes were characterized and analysed for a set of 122 and 110 specimens, respectively, collected along the entire distribution range of the species. Additionally, shape variations were evaluated for 92 individuals (43 males and 49 females) through geometric morphometric methods. Our analyses demonstrated several cases of significantly high levels of genetic differentiation among individual populations, in an isolation-by-distance pattern of divergence, with at least six different population groups along the Patos-Mirim lagoon. These groups differed by a minimum of 0.9% and a maximum of 2.6% of corrected cyt b nucleotide distances and did not share any mitochondrial haplotype. Such a pattern, added to the slight morphometric differentiation detected for most of the groups, suggests the occurrence of incipient speciation as consequence of allopatric fragmentation. The chronophylogenetic tree performed with the concatenated dataset supported independent oriental and occidental colonization routes, with the population located in the northwest part of the Rio Grande do Sul coastal plain presenting the most ancient divergence. In general, the recovered biogeographic patterns are highly consistent with the records of Quaternary climatic changes and depositional events that have occurred along the area inhabited by the studied species. This allowed us to establish a molecular clock calibration system for Neotropical annual fish. Thus, although the taxonomic status of each of the detected population units needs further study, it is clear that independent conservation strategies must be taken in each of the major areas covered by this study, most of which are located in Brazil. 相似文献
44.
Segat L Bevilacqua D Boniotto M Arraes LC de Souza PR de Lima Filho JL Crovella S 《Immunogenetics》2006,58(5-6):471-473
In our study, we identified a polymorphism (C-607A) in the promoter region of the IL-18 gene that shows different frequencies between human immunodeficiency virus (HIV)-1-infected children and healthy controls in a pediatric Brazilian population. The presence of the −607 C allele correlates to HIV-1 infection and confers an increased risk of infection in subjects carrying the single nucleotide polymorphism. 相似文献
45.
Disorders of mitochondrial fat metabolism lead to sudden death in infants and children. Although survival is possible, the underlying molecular mechanisms which enable this outcome have not yet been clearly identified. Here we describe a conserved genetic network linking disorders of mitochondrial fat metabolism in mice to mechanisms of fat storage and survival in Caenorhabditis elegans (C. elegans). We have previously documented a mouse model of mitochondrial very-long chain acyl-CoA dehydrogenase (VLCAD) deficiency. We originally reported that the mice survived birth, but, upon exposure to cold and fasting stresses, these mice developed cardiac dysfunction, which greatly reduced survival. We used cDNA microarrays to outline the induction of several markers of lipid metabolism in the heart at birth in surviving mice. We hypothesized that the induction of fat metabolism genes in the heart at birth is part of a regulatory feedback circuit that plays a critical role in survival. The present study uses a dual approach employing both C57BL/6 mice and the nematode, C. elegans, to focus on TMEM135, a conserved protein which we have found to be upregulated 4.3 (±0.14)-fold in VLCAD-deficient mice at birth. Our studies have demonstrated that TMEM135 is highly expressed in mitochondria and in fat-loaded tissues in the mouse. Further, when fasting and cold stresses were introduced to mice, we observed 3.25 (±0.03)- and 8.2 (±0.31)-fold increases in TMEM135 expression in the heart, respectively. Additionally, we found that deletion of the tmem135 orthologue in C. elegans caused a 41.8% (±2.8%) reduction in fat stores, a reduction in mitochondrial action potential and decreased longevity of the worm. In stark contrast, C. elegans transgenic animals overexpressing TMEM-135 exhibited increased longevity upon exposure to cold stress. Based on these results, we propose that TMEM135 integrates biological processes involving fat metabolism and energy expenditure in both the worm (invertebrates) and in mammalian organisms. The data obtained from our experiments suggest that TMEM135 is part of a regulatory circuit that plays a critical role in the survival of VLCAD-deficient mice and perhaps in other mitochondrial genetic defects of fat metabolism as well. 相似文献
46.
Lilian Rose Pratt-Riccio Daiana de Souza Perce-da-Silva Josué da Costa Lima-Junior Michael Theisen Fátima Santos Cláudio Tadeu Daniel-Ribeiro Joseli de Oliveira-Ferreira Dalma Maria Banic 《Memórias do Instituto Oswaldo Cruz》2013,108(4):523-528
The genetic diversity displayed by Plasmodium
falciparum, the most deadly Plasmodium species, is
a significant obstacle for effective malaria vaccine development. In this study,
we identified genetic polymorphisms in P. falciparum
glutamate-rich protein (GLURP), which is currently being tested in clinical
trials as a malaria vaccine candidate, from isolates found circulating in the
Brazilian Amazon at variable transmission levels. The study was performed using
samples collected in 1993 and 2008 from rural villages situated near Porto
Velho, in the state of Rondônia. DNA was extracted from 126 P.
falciparum-positive thick blood smears using the phenol-chloroform
method and subjected to a nested polymerase chain reaction protocol with
specific primers against two immunodominant regions of GLURP, R0 and R2. Only
one R0 fragment and four variants of the R2 fragment were detected. No
differences were observed between the two time points with regard to the
frequencies of the fragment variants. Mixed infections were uncommon. Our
results demonstrate conservation of GLURP-R0 and limited polymorphic variation
of GLURP-R2 in P. falciparum isolates from individuals living
in Porto Velho. This is an important finding, as genetic polymorphisms in B and
T-cell epitopes could have implications for the immunological properties of the
antigen. 相似文献
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48.
Martino A Cabiati M Campan M Prescimone T Minocci D Caselli C Rossi AM Giannessi D Del Ry S 《Journal of biotechnology》2011,153(3-4):92-99
Real-time PCR is the benchmark method for measuring mRNA expression levels, but the accuracy and reproducibility of its data greatly depend on appropriate normalization strategies. Though the minipig model is largely used to study cardiovascular disease, no specific reference genes have been identified in porcine myocardium. The aim of the study was to identify and validate reference gene to be used in RT-PCR studies of failing (HF) and non-failing pig hearts. Eight candidate reference genes (GAPDH, ACTB, B2M, TBP, HPRT-1, PPIA, TOP2B, YWHAZ) were selected to compare cardiac tissue of normal (n=4) and HF (n=5) minipigs. The most stable genes resulted: HPRT-1, TBP, PPIA (right and left atrium); PPIA, GAPDH, ACTB (right ventricle); HPRT-1, TBP, GAPDH (left ventricle). The normalization strategy was tested analyzing mRNA expression of TNF-α, which is known to be up-regulated in HF and whose variations resulted more significant when normalized with the appropriately selected reference genes. The findings obtained in this study underline the importance to provide a set of reference genes to normalize mRNA expression in HF and control minipigs. The use of unvalidated reference genes can generate biased results because also their expression could be altered by the experimental conditions. 相似文献
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