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排序方式: 共有152条查询结果,搜索用时 31 毫秒
1.
Elvira Maniccia-Bozzo Myrna Bueno Espiritu Gurmit Singh 《Molecular and cellular biochemistry》1990,94(1):83-88
The objective of this study was to determine if the nephrotoxic effects induced by cisplatin were correlated to mitochondrial DNA damage. Comparisons were made with the liver since hepatotoxicity is rarely observed. Cisplatin doses of 10, 20 and 40 mg/kg were administered intraperitoneally to C57BL/6J mice. Mitochrondrial DNA was isolated from both the hepatic and renal tissues and quantitated by hybridization with a specific mitochondrial probe. Cisplatin caused differential effects on mouse hepatic and renal mitochondrial DNA. The 10 and 20 mg/kg dose caused an elevation in mitochondrial DNA levels in the hepatic, but no increase in the renal tissue was observed. This is the first study demonstrating an organ specific effect of cisplatin at the DNA level. 相似文献
2.
This study shows that mitochondria in liver, kidney, heart, and brain of the mouse have a distinct mitochondrial density. It also demonstrates that the mtDNA copy number per mitochondrion is organ-specific. A reliable method of determining mitochondrial density per organ is by stereological analysis of tissue sections while mtDNA quantitation is by the use of radiolabelled mtDNA probe. This is the first study in which a comprehensive examination of mitochondrial density and quantitation of mitochondrial genomes in mouse organs have been done. In summary the variability is not only in mitochondrial density but also in genomic copy number in mitochondria of various tissues. 相似文献
3.
Cecilia C. Klein Jo?o M. P. Alves Myrna G. Serrano Gregory A. Buck Ana Tereza R. Vasconcelos Marie-France Sagot Marta M. G. Teixeira Erney P. Camargo Maria Cristina M. Motta 《PloS one》2013,8(11)
Some non-pathogenic trypanosomatids maintain a mutualistic relationship with a betaproteobacterium of the Alcaligenaceae family. Intensive nutritional exchanges have been reported between the two partners, indicating that these protozoa are excellent biological models to study metabolic co-evolution. We previously sequenced and herein investigate the entire genomes of five trypanosomatids which harbor a symbiotic bacterium (SHTs for Symbiont-Haboring Trypanosomatids) and the respective bacteria (TPEs for Trypanosomatid Proteobacterial Endosymbiont), as well as two trypanosomatids without symbionts (RTs
for Regular Trypanosomatids), for the presence of genes of the classical pathways for vitamin biosynthesis. Our data show that genes for the biosynthetic pathways of thiamine, biotin, and nicotinic acid are absent from all trypanosomatid genomes. This is in agreement with the absolute growth requirement for these vitamins in all protozoa of the family. Also absent from the genomes of RTs are the genes for the synthesis of pantothenic acid, folic acid, riboflavin, and vitamin B6. This is also in agreement with the available data showing that RTs are auxotrophic for these essential vitamins. On the other hand, SHTs are autotrophic for such vitamins. Indeed, all the genes of the corresponding biosynthetic pathways were identified, most of them in the symbiont genomes, while a few genes, mostly of eukaryotic origin, were found in the host genomes. The only exceptions to the latter are: the gene coding for the enzyme ketopantoate reductase (EC:1.1.1.169) which is related instead to the Firmicutes bacteria; and two other genes, one involved in the salvage pathway of pantothenic acid and the other in the synthesis of ubiquinone, that are related to Gammaproteobacteria. Their presence in trypanosomatids may result from lateral gene transfer. Taken together, our results reinforce the idea that the low nutritional requirement of SHTs is associated with the presence of the symbiotic bacterium, which contains most genes for vitamin production. 相似文献
4.
Juan Jia Zhenjiao Cao Chengzhu Liu Zhenhua Zhang Li Lin Yiyun Wang Negar Haghipour Lukas Wacker Hongyan Bao Thorston Dittmar Myrna J. Simpson Huan Yang Thomas W. Crowther Timothy I. Eglinton Jin‐Sheng He Xiaojuan Feng 《Global Change Biology》2019,25(12):4383-4393
Subsoil contains more than half of soil organic carbon (SOC) globally and is conventionally assumed to be relatively unresponsive to warming compared to the topsoil. Here, we show substantial changes in carbon allocation and dynamics of the subsoil but not topsoil in the Qinghai‐Tibetan alpine grasslands over 5 years of warming. Specifically, warming enhanced the accumulation of newly synthesized (14C‐enriched) carbon in the subsoil slow‐cycling pool (silt‐clay fraction) but promoted the decomposition of plant‐derived lignin in the fast‐cycling pool (macroaggregates). These changes mirrored an accumulation of lipids and sugars at the expense of lignin in the warmed bulk subsoil, likely associated with shortened soil freezing period and a deepening root system. As warming is accompanied by deepening roots in a wide range of ecosystems, root‐driven accrual of slow‐cycling pool may represent an important and overlooked mechanism for a potential long‐term carbon sink at depth. Moreover, given the contrasting sensitivity of SOC dynamics at varied depths, warming studies focusing only on surface soils may vastly misrepresent shifts in ecosystem carbon storage under climate change. 相似文献
5.
Schneider Céline M. Steeves Katherine L. Mercer Grace V. George Hannah Paranavitana Leah Simpson Myrna J. Simpson André J. Cahill Lindsay S. 《Metabolomics : Official journal of the Metabolomic Society》2022,18(1):1-11
Metabolomics - The study of lipoprotein metabolism at the population level can provide valuable information for the organisation of lipoprotein related processes in the body. To use this... 相似文献
6.
Yannik Bollen Joris H. Hageman Petra van Leenen Lucca L. M. Derks Bas Ponsioen Julian R. Buissant des Amorie Ingrid Verlaan-Klink Myrna van den Bos Leon W. M. M. Terstappen Ruben van Boxtel Hugo J. G. Snippert 《PLoS biology》2022,20(1)
CRISPR-associated nucleases are powerful tools for precise genome editing of model systems, including human organoids. Current methods describing fluorescent gene tagging in organoids rely on the generation of DNA double-strand breaks (DSBs) to stimulate homology-directed repair (HDR) or non-homologous end joining (NHEJ)-mediated integration of the desired knock-in. A major downside associated with DSB-mediated genome editing is the required clonal selection and expansion of candidate organoids to verify the genomic integrity of the targeted locus and to confirm the absence of off-target indels. By contrast, concurrent nicking of the genomic locus and targeting vector, known as in-trans paired nicking (ITPN), stimulates efficient HDR-mediated genome editing to generate large knock-ins without introducing DSBs. Here, we show that ITPN allows for fast, highly efficient, and indel-free fluorescent gene tagging in human normal and cancer organoids. Highlighting the ease and efficiency of ITPN, we generate triple fluorescent knock-in organoids where 3 genomic loci were simultaneously modified in a single round of targeting. In addition, we generated model systems with allele-specific readouts by differentially modifying maternal and paternal alleles in one step. ITPN using our palette of targeting vectors, publicly available from Addgene, is ideally suited for generating error-free heterozygous knock-ins in human organoids.A major downside of double-strand break-mediated genome editing is the need to verify the genomic integrity of the targeted locus and confirm the absence of off-target indels. This study shows that in-trans paired nicking is a mutation-free CRISPR strategy to introduce precise knock-ins into human organoids; its genomic fidelity allows all knock-in cells to be pooled, accelerating the establishment of new organoid models. 相似文献
8.
Neither agouti-related protein nor neuropeptide Y is critically required for the regulation of energy homeostasis in mice 总被引:11,自引:0,他引:11
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Qian S Chen H Weingarth D Trumbauer ME Novi DE Guan X Yu H Shen Z Feng Y Frazier E Chen A Camacho RE Shearman LP Gopal-Truter S MacNeil DJ Van der Ploeg LH Marsh DJ 《Molecular and cellular biology》2002,22(14):5027-5035
Agouti-related protein (AgRP), a neuropeptide abundantly expressed in the arcuate nucleus of the hypothalamus, potently stimulates feeding and body weight gain in rodents. AgRP is believed to exert its effects through the blockade of signaling by alpha-melanocyte-stimulating hormone at central nervous system (CNS) melanocortin-3 receptor (Mc3r) and Mc4r. We generated AgRP-deficient (Agrp(-/-)) mice to examine the physiological role of AgRP. Agrp(-/-) mice are viable and exhibit normal locomotor activity, growth rates, body composition, and food intake. Additionally, Agrp(-/-) mice display normal responses to starvation, diet-induced obesity, and the administration of exogenous leptin or neuropeptide Y (NPY). In situ hybridization failed to detect altered CNS expression levels for proopiomelanocortin, Mc3r, Mc4r, or NPY mRNAs in Agrp(-/-) mice. As AgRP and the orexigenic peptide NPY are coexpressed in neurons of the arcuate nucleus, we generated AgRP and NPY double-knockout (Agrp(-/-);Npy(-/-)) mice to determine whether NPY or AgRP plays a compensatory role in Agrp(-/-) or NPY-deficient (Npy(-/-)) mice, respectively. Similarly to mice deficient in either AgRP or NPY, Agrp(-/-);Npy(-/-) mice suffer no obvious feeding or body weight deficits and maintain a normal response to starvation. Our results demonstrate that neither AgRP nor NPY is a critically required orexigenic factor, suggesting that other pathways capable of regulating energy homeostasis can compensate for the loss of both AgRP and NPY. 相似文献
9.
10.
Pedro Paulo de Abreu Manso Barbara C. E. P. Dias de Oliveira Patrícia Carvalho de Sequeira Yuli Rodrigues Maia de Souza Jessica Maria dos Santos Ferro Igor José da Silva Luzia Fátima Gon?alves Caputo Priscila Tavares Guedes Alexandre Araujo Cunha dos Santos Marcos da Silva Freire Myrna Cristina Bonaldo Marcelo Pelajo-Machado 《PLoS neglected tropical diseases》2015,9(9)
The yellow fever (YF) 17D vaccine is one of the most effective human vaccines ever created. The YF vaccine has been produced since 1937 in embryonated chicken eggs inoculated with the YF 17D virus. Yet, little information is available about the infection mechanism of YF 17DD virus in this biological model. To better understand this mechanism, we infected embryos of Gallus gallus domesticus and analyzed their histopathology after 72 hours of YF infection. Some embryos showed few apoptotic bodies in infected tissues, suggesting mild focal infection processes. Confocal and super-resolution microscopic analysis allowed us to identify as targets of viral infection: skeletal muscle cells, cardiomyocytes, nervous system cells, renal tubular epithelium, lung parenchyma, and fibroblasts associated with connective tissue in the perichondrium and dermis. The virus replication was heaviest in muscle tissues. In all of these specimens, RT-PCR methods confirmed the presence of replicative intermediate and genomic YF RNA. This clearer characterization of cell targets in chicken embryos paves the way for future development of a new YF vaccine based on a new cell culture system. 相似文献