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511.
Homo- and heteroplasmic mitochondrial DNA (mtDNA) mutations were observed and identified in an isoproterenol-induced rabbit model of cardiac hypertrophy. Genes encoding proteins essential for catalyzing mitochondrial electron transfer and for generating the proton motive force, such as NADH dehydrogenases (ND2, ND3, ND4, and ND6), cytochrome b, and ATPase 8, showed increased susceptibility for mutation. Specifically, five mutations caused amino acid changes and were located in Complex I and Complex V gene clusters. To our knowledge, this is the first demonstration of a relationship between cardiac hypertrophy induced by a strong sympathetic load and rapid mtDNA mutations. 相似文献
512.
Caws M Thwaites G Dunstan S Hawn TR Lan NT Thuong NT Stepniewska K Huyen MN Bang ND Loc TH Gagneux S van Soolingen D Kremer K van der Sande M Small P Anh PT Chinh NT Quy HT Duyen NT Tho DQ Hieu NT Torok E Hien TT Dung NH Nhu NT Duy PM van Vinh Chau N Farrar J 《PLoS pathogens》2008,4(3):e1000034
The factors that govern the development of tuberculosis disease are incompletely understood. We hypothesized that some strains of Mycobacterium tuberculosis (M. tuberculosis) are more capable of causing disseminated disease than others and may be associated with polymorphisms in host genes responsible for the innate immune response to infection. We compared the host and bacterial genotype in 187 Vietnamese adults with tuberculous meningitis (TBM) and 237 Vietnamese adults with uncomplicated pulmonary tuberculosis. The host genotype of tuberculosis cases was also compared with the genotype of 392 cord blood controls from the same population. Isolates of M. tuberculosis were genotyped by large sequence polymorphisms. The hosts were defined by polymorphisms in genes encoding Toll-interleukin 1 receptor domain containing adaptor protein (TIRAP) and Toll-like receptor-2 (TLR-2). We found a significant protective association between the Euro-American lineage of M. tuberculosis and pulmonary rather than meningeal tuberculosis (Odds ratio (OR) for causing TBM 0.395, 95% confidence intervals (C.I.) 0.193-0.806, P = 0.009), suggesting these strains are less capable of extra-pulmonary dissemination than others in the study population. We also found that individuals with the C allele of TLR-2 T597C allele were more likely to have tuberculosis caused by the East-Asian/Beijing genotype (OR = 1.57 [95% C.I. 1.15-2.15]) than other individuals. The study provides evidence that M. tuberculosis genotype influences clinical disease phenotype and demonstrates, for the first time, a significant interaction between host and bacterial genotypes and the development of tuberculosis. 相似文献
513.
Net Ecosystem Exchanges of Carbon, Water, and Energy in Young and Old-growth Douglas-Fir Forests 总被引:1,自引:1,他引:0
Jiquan Chen Kyaw Tha Paw U Susan L. Ustin Thomas H. Suchanek Barbara J. Bond Kimberley D. Brosofske Matthias Falk 《Ecosystems》2004,7(5):534-544
To be able to estimate the cumulative carbon budget at broader scales, it is essential to understand net ecosystem exchanges (NEE) of carbon and water in various ages and types of ecosystems. Using eddy-covariance (EC) in Douglas-fir dominated forests in the Wind River Valley, Washington, USA, we measured NEE of carbon, water, and energy from July through September in a 40-year-old stand (40YR) in 1998, a 20-year-old stand (20YR) in 1999, and a 450-year-old stand (450YR) during both years. All three stands were net carbon sinks during the dry, warm summers, with mean net daily accumulation of –0.30 g C m–2 d–1, –2.76 g C m–2 d–1, and –0.38 g C m–2 d–1, respectively, in the 20YR, 40YR, and 450YR (average of 1998, 1999) stands; but for individual years, the 450YR stand was a carbon source in 1998 (0.51 g C m–2 d–1) and a sink in 1999 (–1.26 g C m–2 d–1). The interannual differences for the summer months were apparent for cumulative carbon exchange at the 450YR stand, which had 46.9 g C m–2 loss in 1998 and 115.9 g C m–2 gain in 1999. As predicted, the 40YR stand assimilated the most carbon and lost the least amount of water to the atmosphere through evapotranspiration. 相似文献
514.
After the successful cloning of the first gene for a polyglutamine disease in 1991, the expanded polyglutamine tract in the nine polyglutamine disease proteins became an obvious therapeutic target. Early hypotheses were that misfolded, precipitated protein could be a universal pathogenic mechanism. However, new data are accumulating on Huntington's disease and other polyglutamine diseases that appear to contradict the toxic aggregate hypothesis. Recent data suggest that the toxic species of protein in these diseases may be soluble mutant conformers, and that the protein context of expanded polyglutamine is critical to understanding disease specificity. Here we discuss recent publications that define other important therapeutic targets for polyglutamine-mediated neurodegeneration related to the context of the expanded polyglutamine tract in the disease protein. 相似文献
515.
Campos-da-Paz M Costa CS Quilici LS de Carmo Simões I Kyaw CM Maranhão AQ Brigido MM 《Molecular biotechnology》2008,39(2):155-158
Recombinant factor VIII is one of the most complex mammalian proteins and a biotechnology venture required for the treatment of hemophilia A. The complexity of the protein, post-translational modifications and limitations of expression elements make the production of active recombinant FVIII a challenge. Here we report the production of biologically active Factor VIII in two different cell lines, CHO and HepG2, by transient transfection. Two expression vectors based on the CMV promoter were used: one harboring CMV Intron A (InA) and the other without it. To bypass difficulties in secretion, we also studied the influence of co-expression of the human splice isoform of the XBP1 gene. We report the production of recombinant FVIII possessing bioengineered FVIII heavy and light chains, linked by a minimal B domain. In our study, HepG2, a human hepatocyte cell line, expressed Factor VIII ten-fold more than a CHO cell line, and in HepG2 cells, the expression of XBP1 improved Factor VIII activity. For CHO cells, expression was improved by the presence of InA, but no further improvement was noted with XBP1 co-expression. These data suggest that the minimal B domain rFVIII preserves Factor VIII biological activity and that different expression elements can be used to improve its production. 相似文献
516.
Hoang Thi Bich Thao Takeo Yamakawa Katsuhiro Shibata Papa Saliou Sarr Aung Kyaw Myint 《Plant and Soil》2008,308(1-2):1-10
Soil and hydroponic culture experiments were conducted to investigate the effects of phosphite (Phi) as phosphorus (P) fertilizer via root and foliar applications on the growth and P supply of komatsuna. In both experiments, root P treatments were combinations of Phi and phosphate (Pi) at different Pi:Phi ratios, for a total of high P level (92 mg P pot?1; the soil experiment) or low P level (0.05 mM P; the hydroponic experiment). Foliar P treatments were deionized water (control), a Pi solution and a Phi solution at low concentration of 0.05% P2O5. In both experiments, shoot dry weight of plants significantly decreased as Pi:Phi ratio decreased. In the soil experiment, plants grew abnormally at a Pi:Phi ratio of 25:75 and died when P was applied to soil entirely as Phi form (0:100 treatment). In the hydroponic experiment, no visible damage was found in shoot but root growth was strongly inhibited with severe damage symptoms at low Pi:Phi ratios. Total P concentration in plant decreased significantly with decreasing Pi:Phi ratio, especially in the hydroponic experiment. Foliar application of Phi although greatly increased total P of plants compared to that of Pi in both experiments, it did not improve but further decreased plant growth at low Pi:Phi ratios in the soil experiment and at all Pi:Phi ratios in the hydroponic experiment. The results of this study clearly indicated that Phi could not be used as P fertilizer by komatsuna plants via both application methods and could not substitute P at any rate at either low or high level. No beneficial effect of Phi was detected even when it was applied at low rate or applied in combination with Pi at different ratios. The effects of Phi were strongly dependent on the P nutrition status of plants; and plants that were not sufficiently fertilized with Pi may become vulnerable to Phi even at low levels. 相似文献
517.
Life cycle assessment of fuel ethanol from cassava in Thailand 总被引:2,自引:0,他引:2
Thu Lan T. Nguyen Shabbir H. Gheewala 《The International Journal of Life Cycle Assessment》2008,13(2):147-154
Goal and Scope A well-to-wheel analysis has been conducted for cassava-based ethanol (CE) in Thailand. The aim of the analysis is to assess
the potentials of CE in the form of gasohol E10 for promoting energy security and reducing environmental impacts in comparison
with conventional gasoline (CG).
Method In the LCA procedure, three separate but interrelated components: inventory analysis, characterization and interpretation
were performed for the complete chain of the fuel life cycle. To compare gasohol E10 and CG, this study addressed their impact
potentials per gasoline-equivalent litre, taking into account the performance difference between gasohol and gasoline in an
explosion motor.
Results and Discussions The results obtained show that CE in the form of E10, along its whole life cycle, reduces certain environmental loads compared
to CG. The percentage reductions relative to CG are 6.1% for fossil energy use, 6.0% for global warming potential, 6.8% for
acidification, and 12.2% for nutrient enrichment. Using biomass in place of fossil fuels for process energy in the manufacture
of ethanol leads to improved overall life cycle energy and environmental performance of ethanol blends relative to CG.
Conclusions and Outlook The LCA brings to light the key areas in the ethanol production cycle that researchers and technicians need to work on to
maximize ethanol’s contribution to energy security and environmental sustainability
ESS-Submission Editor: Mark Goedkoop (goedkoop@pre.nl) 相似文献
518.
Marivaux L Beard KC Chaimanee Y Jaeger JJ Marandat B Soe AN Tun ST Kyaw AA 《American journal of physical anthropology》2008,137(3):263-273
The postcranial anatomy of the Asian sivaladapid adapiforms is still virtually undocumented, whereas dental remains of these primates have been known for several decades. Little is known about their positional behavior as a result. In this article, we describe a partial left femur of a medium-sized primate preserving its entire proximal portion and a significant length of its shaft. This fossil was recently recovered from the fossiliferous locality of Thamingyauk in the late middle Eocene Pondaung Formation (central Myanmar). This femur is considered to pertain to the same individual as two tarsal elements (fragmentary talus and calcaneus) from the same locality (same location), and attributed to a medium-sized sivaladapid adapiform primate (Kyitchaungia takaii). This new postcranial element provides the first documentation of femoral anatomy among Sivaladapidae from Asia. The mechanical implications deriving from the musculoskeletal interpretation of this bone indicate an animal that probably engaged in a kind of active arboreal quadrupedalism with some degree of proficiency in leaping. Even though many musculoskeletal aspects suggest that branch walking and running were important parts of its locomotor repertoire, in other details it appears that relatively complex movements at the hip joint were actually possible and probably associated with climbing or some hindlimb suspensory activities. 相似文献
519.
The intestinal epithelial cell-surface molecule, CD98 is a type II membrane glycoprotein. Molecular orientation studies have demonstrated that the C-terminal tail of human CD98 (hCD98), which contains a PDZ-binding domain, is extracellular. In intestinal epithelial cells, CD98 is covalently linked to an amino-acid transporter with which it forms a heterodimer. This heterodimer associates with beta(1)-integrin and intercellular adhesion molecular 1 (ICAM-1) to form a macromolecular complex in the basolateral membranes of polarized intestinal epithelial cells. This review focuses on the multifunctional roles of CD98, including involvement in extracellular signaling, adhesion/polarity, and amino-acid transporter expression in intestinal epithelia. A role for CD98 in intestinal inflammation, such as Intestinal Bowel Disease (IBD), is also proposed. 相似文献
520.
MASTR-MS: a web-based collaborative laboratory information management system (LIMS) for metabolomics
Adam Hunter Saravanan Dayalan David De Souza Brad Power Rodney Lorrimar Tamas Szabo Thu Nguyen Sean O’Callaghan Jeremy Hack James Pyke Amsha Nahid Roberto Barrero Ute Roessner Vladimir Likic Dedreia Tull Antony Bacic Malcolm McConville Matthew Bellgard 《Metabolomics : Official journal of the Metabolomic Society》2017,13(2):14