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101.
The ecosystem carbon budget was estimated in a Japanese Zoysia japonica grassland. The green biomass started to grow in May and peaked from mid-July to September. Seasonal variations in soil CO2 flux and root respiration were mediated by changes in soil temperature. Annual soil CO2 flux was 1,121.4 and 1,213.6 g C m−2 and root respiration was 471.0 and 544.3 g C m−2 in 2007 and 2008, respectively. The root respiration contribution to soil CO2 flux ranged from 33% to 71%. During the growing season, net primary production (NPP) was 747.5 and 770.1 g C m−2 in 2007 and 2008, respectively. The biomass removed by livestock grazing (GL) was 122.1 and 102.7 g C m−2, and the livestock returned 28.2 and 25.6 g C m−2 as fecal input (FI) in 2007 and 2008, respectively. The decomposition of FI (DL, the dry weight loss due to decomposition) was very low, 1.5 and 1.4 g C m−2, in 2007 and 2008. Based on the values of annual NPP, soil CO2 flux, root respiration, GL, FI, and DL, the estimated carbon budget of the grassland was 1.7 and 22.3 g C m−2 in 2007 and 2008, respectively. Thus, the carbon budget of this Z. japonica grassland ecosystem remained in equilibrium with the atmosphere under current grazing conditions over the 2 years of the study.  相似文献   
102.
The prophylactic efficacies of several multivalent replication-incompetent adenovirus serotype 5 (Ad5) vaccines were examined in rhesus macaques using an intrarectal high-dose simian immunodeficiency virus SIVmac239 challenge model. Cohorts of Mamu-A*01+/B*17 Indian rhesus macaques were immunized with one of several combinations of Ad5 vectors expressing Gag, Pol, Nef, and Env gp140; for comparison, a Mamu-A*01+ cohort was immunized using the Ad5 vector alone. There was no sign of immunological interference between antigens in the immunized animals. In general, expansion of the antigen breadth resulted in more favorable virological outcomes. In particular, the order of efficacy trended as follows: Gag/Pol/Nef/Env ≈ Gag/Pol > Gag ≈ Gag/Pol/Nef > Nef. However, the precision in ranking the vaccines based on the study results may be limited by the cohort size, and as such, may warrant additional testing. The implications of these results in light of the recent discouraging results of the phase IIb study of the trivalent Ad5 HIV-1 vaccine are discussed.There is a significant body of evidence suggesting that anti-human immunodeficiency virus type 1 (HIV-1) cellular immunity plays a prominent role in controlling viral infection and progression to disease (15, 32, 33). This stimulated substantial research into vaccines capable of eliciting this type of immunity, and several vaccine candidates (5, 6, 8-13, 22, 29-31, 35) have reached various stages of clinical development. However, the viability of this general vaccine approach was recently undermined by the findings in a phase II trial (called the Step Study) that immunization with a replication-defective adenovirus serotype 5 (Ad5) vaccine expressing HIV-1 clade B Gag, Pol, and Nef was not effective in either reducing acquisition rates and/or lowering set point viral loads in infected subjects (2, 25). In fact, more infections were originally observed in the vaccine group than in the placebo arm (2).The outcomes of the Step Study led to several important questions. Do the results argue against the concept of a HIV-1 vaccine based on the induction of specific T lymphocytes? On the other hand, if cytotoxic T-lymphocyte (CTL) responses are intrinsically valuable for an effective vaccine, what are the shortcomings in the vaccine-induced immunity that contributed to the lack of efficacy in the Step trial? What is the predictive value of preclinical challenge studies for selection of future clinical vaccine candidates? The potential role of CTL responses in an effective vaccine is also challenged by the recently reported phase III study results for the ALVAC vCP1521 prime-AIDSVAX B/E boost vaccine. The efficacy of this vaccine in a low-risk population was recently shown to trend toward prevention of HIV acquisition and not reduction of viral loads (30). Unlike the Step study vaccine, the ALVAC/AIDSVAX vaccine approach utilized a heterologous prime-boost regimen and contained an Env component that may have contributed to the type of outcome observed here. A better understanding of the immune correlates for this vaccine may be possible following further experimental investigations of the samples collected from the phase III study and earlier-stage trials.Despite the proven efficacy of Ad5 vaccination against simian-human immunodeficiency virus 89.6P (SHIV89.6P) challenge, subsequent primate studies provided equivocal results. In a homologous prime-boost regimen, Ad5 vaccine expressing Gag was ineffective against a high-dose simian immunodeficiency virus SIVmac239 challenge (4, 24). The same study compared this regimen with the DNA prime/Ad5 boost regimen that was found to be efficacious in Mamu-A*01+ monkeys; the level of protection in the overall study was correlated with the breadth of epitopes recognized and the frequency of induced antigen-specific CTLs. In this study, we examine whether the expansion of antigens to include Pol, Nef, and Env gp140 using the Ad5/Ad5 regimen would improve the outcome against the same high-dose SIV challenge. Of particular interest is the combination of Gag, Pol, and Nef, for which the homologous human vaccine was utilized in the Step study (29).  相似文献   
103.
The efficacy of four potential phosphate solubilizing Enterobacter isolated from non-rhizospheric soil in Western ghat forest in India. Plant growth promoting ability of these isolates was evaluated in cowpea. All are gram negative, rod shaped, 0.8–1.6 mm in size, and psychrotrophic in nature, grow from 5 to 40°C (optimum temp. 28 ± 2°C). All isolates exhibits growth at a wide range of pH 6–12, optimum at pH 7.0 and tolerates up to 7% (w/v) salt concentration. 16S rRNA gene sequencing reveals the confirmation of isolates to Enterobacter aerogenes sp. (NII-0907 and NII-0929), Enterobacter cloacae subsp. cloacae sp. (NII-0931) and Enterobacter asburiae sp. (NII-0934) with which they share >99% sequence similarity. Under in vitro conditions, all the four isolates were found to produce indole acetic acid, P-solubilization and hydrogen cyanide. The P-solubilizing activity coincided with a concomitant decrease in pH of the medium (pH 7.0–<3.0). The plant growth promotion properties were demonstrated through a cow pea (Vigna unguiculata (L.) walp) based bioassay under greenhouse conditions. Although the bacterial inoculation was found to result in significant increment in root, shoot and biomass and it stimulated bacterial counts in the rhizosphere. Hence, these isolates can further formulated and used for field application.  相似文献   
104.
A phosphate-solubilizing bacterial strain NII-0909 isolated from the Western ghat forest soil in India was identified as Micrococcus sp on the basis of phenotypic characteristics, carbon source utilization pattern, fatty acid methyl esters analysis, and 16S rRNA gene sequence. The strain exhibited the plant growth-promoting attributes of phosphate solubilization, auxin production, 1-aminocyclopropane-1-carboxylate deaminase activity, and siderophore production. It was able to solubilize (122.4 μg of Ca3PO4 ml?1), and produce IAA (109 μg ml?1) at 30 °C. P-solubilizing activity of the strain NII-0909 was associated with the release of organic acids and a drop in the pH of the NBRIP medium. HPLC analysis detected two organic acids in the course of P-solubilization. A significant increase in the growth of cow pea was recorded for inoculations under controlled conditions. Scanning electron microscopic study revealed the root colonization of strain on cow pea seedlings. These results demonstrate that isolates NII-0909 has the promising PGPR attributes to be develop as a biofertilizer to enhance soil fertility and promote the plant growth.  相似文献   
105.
Horsegram (Dolichos biflorus), a protein-rich leguminous pulse, native to Southeast Asia and tropical Africa, contains multiple forms of BowmanBirk inhibitors. The major BowmanBirk inhibitor from horsegram (HGI-III) was cloned and functionally expressed in Escherichiacoli (rHGI), which moved as a dimer in solution similar to the natural inhibitor. The biochemical characterization of rHGI also points to its close resemblance with HGI-III not only in its structure but also in its inhibitory characteristics. To explore the electrostatic interactions involved in the dimerization, a site-directed mutagenesis approach was used. The role of reactive site residue K24 and the C-terminal Asp in the structure and stability of the dimer was accomplished by mutating K24 and D75/76. The mutants produced in this study confirm that the self-association of HGI-III is indeed due to the electrostatic interaction between K24 of one monomer and D75/76 of the second monomer, in agreement with our previous data. The functional expression of a BowmanBirk inhibitor minus a fusion tag serves as a platform to study the structural and functional effects of the special pattern of seven conserved disulphide bridges.  相似文献   
106.
Mycobacterium tuberculosis and Mycobacterium bovis bacille Calmette-Guérin (BCG) alter the maturation of their phagosomes and reside within a compartment that resists acidification and fusion with lysosomes. To define the molecular composition of this compartment, we developed a novel method for obtaining highly purified phagosomes from BCG-infected human macrophages and analyzed the phagosomes by Western immunoblotting and mass spectrometry-based proteomics. Our purification procedure revealed that BCG grown on artificial medium becomes less dense after growth in macrophages. By Western immunoblotting, LAMP-2, Niemann-Pick protein C1, and syntaxin 3 were readily detectable on the BCG phagosome but at levels that were lower than on the latex bead phagosome; flotillin-1 and the vacuolar ATPase were barely detectable on the BCG phagosome but highly enriched on the latex bead phagosome. Immunofluorescence studies confirmed the scarcity of flotillin on BCG phagosomes and demonstrated an inverse correlation between bacterial metabolic activity and flotillin on M. tuberculosis phagosomes. By mass spectrometry, 447 human host proteins were identified on BCG phagosomes, and a partially overlapping set of 289 human proteins on latex bead phagosomes was identified. Interestingly, the majority of the proteins identified consistently on BCG phagosome preparations were also identified on latex bead phagosomes, indicating a high degree of overlap in protein composition of these two compartments. It is likely that many differences in protein composition are quantitative rather than qualitative in nature. Despite the remarkable overlap in protein composition, we consistently identified a number of proteins on the BCG phagosomes that were not identified in any of our latex bead phagosome preparations, including proteins involved in membrane trafficking and signal transduction, such as Ras GTPase-activating-like protein IQGAP1, and proteins of unknown function, such as FAM3C. Our phagosome purification procedure and initial proteomics analyses set the stage for a quantitative comparative analysis of mycobacterial and latex bead phagosome proteomes.Mycobacterium tuberculosis, the etiological agent of tuberculosis, is a facultative intracellular bacterium. In human macrophages, M. tuberculosis resides in a membrane-bound phagosomal compartment that resists fusion with lysosomes and is only mildly acidified (15). In previous studies, using the cryosection immunogold technique, we have found that the M. tuberculosis phagosome exhibits delayed clearance of major histocompatability complex class I molecules and relatively weak staining for lysosomal membrane glycoproteins CD63, LAMP-1,1 and LAMP-2 and the lysosomal acid protease cathepsin D (610). Studies by other investigators have also demonstrated that M. tuberculosis and other mycobacterial species, including Mycobacterium bovis BCG, reside in phagosomes that resist acidification, are less mature, and less fusogenic with lysosomes than phagosomes containing inert particles (1113). These results are consistent with the hypothesis that M. tuberculosis and M. bovis BCG retard the maturation of their phagosomes along the endolysosomal pathway and reside in a compartment that has not matured fully to a phagolysosome (7). Although the phagosomes of latex beads have been subjected to detailed proteomics analysis by Desjardins and co-workers (14), a detailed proteomics study of the M. bovis BCG phagosome has not been reported previously.We describe in this study a novel method for the purification of the BCG phagosome from infected human macrophages, a detailed proteomics analysis of the BCG phagosome, and a comparison of the phagosome with latex bead phagosomes isolated from human macrophages. This study is the first comprehensive proteomics study of the M. bovis BCG phagosome and the first mass spectrometry-based proteomics study of the latex bead phagosome in human macrophages. We showed by Western immunoblotting that, relative to latex bead phagosomes, the BCG phagosome is relatively depleted in LAMP-2, NPC1, flotillin-1, vATPase, and syntaxin 3. Remarkably, by mass spectrometry, we documented a high degree of overlap in the set of proteins on BCG and latex bead phagosomes but also noteworthy differences. Novel proteins detected on the BCG phagosome but not on the latex bead phagosome include CD44, intercellular adhesion molecule 1, protein FAM3C, Ral-A/Ral-B, stress-induced phosphoprotein 1, band 4.1-like protein 3, septin-7, Ras GTPase-activating protein-like protein IQGAP1, Rab-6A, erlin-2, and tumor protein D54. Conversely, proteins identified on latex bead phagosomes but not on the BCG phagosome are β-galactosidase and sialate O-acetylesterase.  相似文献   
107.
Because firing properties and metabolic rates vary widely, neurons require different transport rates from their Na(+)/K(+) pumps in order to maintain ion homeostasis. In this study we show that Na(+)/K(+) pump activity is tightly regulated by a novel process, RNA editing. Three codons within the squid Na(+)/K(+) ATPase gene can be recoded at the RNA level, and the efficiency of conversion for each varies dramatically, and independently, between tissues. At one site, a highly conserved isoleucine in the seventh transmembrane span can be converted to a valine, a change that shifts the pump's intrinsic voltage dependence. Mechanistically, the removal of a single methyl group specifically targets the process of Na(+) release to the extracellular solution, causing a higher turnover rate at the resting membrane potential.  相似文献   
108.

Background

Angiogenesis plays an important role in a wide range of physiological processes, and many diseases are associated with the dysregulation of angiogenesis. Radix Astragali is a Chinese medicinal herb commonly used for treating cardiovascular disorders and has been shown to possess angiogenic effect in previous studies but its active constituent and underlying mechanism remain unclear. The present study investigates the angiogenic effects of calycosin, a major isoflavonoid isolated from Radix Astragali, in vitro and in vivo.

Methodology

Tg(fli1:EGFP) and Tg(fli1:nEGFP) transgenic zebrafish embryos were treated with different concentrations of calycosin (10, 30, 100 µM) from 72 hpf to 96 hpf prior morphological observation and angiogenesis phenotypes assessment. Zebrafish embryos were exposed to calycosin (10, 100 µM) from 72 hpf to 78 hpf before gene-expression analysis. The effects of VEGFR tyrosine kinase inhibitor on calycosin-induced angiogenesis were studied using 72 hpf Tg(fli1:EGFP) and Tg(fli1:nEGFP) zebrafish embryos. The pro-angiogenic effects of calycosin were compared with raloxifene and tamoxifen in 72 hpf Tg(fli1:EGFP) zebrafish embryos. The binding affinities of calycosin to estrogen receptors (ERs) were evaluated by cell-free and cell-based estrogen receptor binding assays. Human umbilical vein endothelial cell cultures (HUVEC) were pretreated with different concentrations of calycosin (3, 10, 30, 100 µM) for 48 h then tested for cell viability and tube formation. The role of MAPK signaling in calycosin-induced angiogenesis was evaluated using western blotting.

Conclusion

Calycosin was shown to induce angiogenesis in human umbilical vein endothelial cell cultures (HUVEC) in vitro and zebrafish embryos in vivo via the up-regulation of vascular endothelial growth factor (VEGF), VEGFR1 and VEGFR2 mRNA expression. It was demonstrated that calycosin acted similar to other selective estrogen receptor modulators (SERMs), such as raloxifene and tamoxifen, by displaying selective potency and affinity to estrogen receptors ERα and ERβ. Our results further indicated that calycosin promotes angiogenesis via activation of MAPK with the involvement of ERK1/2 and ER. Together, this study revealed, for the first time, that calycosin acts as a selective estrogen receptor modulator (SERM) to promote angiogenesis, at least in part through VEGF-VEGFR2 and MAPK signaling pathways.  相似文献   
109.

Background

The Evidence-Based Practice (EBP) Project has been investigating the implementation of evidence-based mental health practices (Assertive Community Treatment, Family Psychoeducation, Integrated Dual Diagnosis Treatment, Illness Management and Recovery, and Supported Employment) in state public mental health systems in the United States since 2001. To date, Project findings have yielded valuable insights into implementation strategy characteristics and effectiveness. This paper reports results of an effort to identify and classify state-level implementation activities and strategies employed across the eight states participating in the Project.

Methods

Content analysis and Greenhalgh et al's (2004) definition of innovation were used to identify and classify state-level activities employed during three phases of EBP implementation: Pre-Implementation, Initial Implementation and Sustainability Planning. Activities were coded from site visit reports created from documents and notes from key informant interviews conducted during two periods, Fall 2002 – Spring 2003, and Spring 2004. Frequency counts and rank-order analyses were used to examine patterns of implementation activities and strategies employed across the three phases of implementation.

Results

One hundred and six discreet implementation activities and strategies were identified as innovative and were classified into five categories: 1) state infrastructure building and commitment, 2) stakeholder relationship building and communications, 3) financing, 4) continuous quality management, and 5) service delivery practices and training. Implementation activities from different categories were employed at different phases of implementation.

Conclusion

Insights into effective strategies for implementing EBPs in mental health and other health sectors require qualitative and quantitative research that seeks to: a) empirically test the effects of tools and methods used to implement EBPs, and b) establish a stronger evidence-base from which to plan, implement and sustain such efforts. This paper offers a classification scheme and list of innovative implementation activities and strategies. The classification scheme offers potential value for future studies that seek to assess the effects of various implementation processes, and helps establish widely accepted standards and criteria that can be used to assess the value of innovative activities and strategies.  相似文献   
110.
Summary Steatohepatitis has recently been increasing as a cofactor influencing the progression of fibrosis, cirrhosis, adenoma and carcinoma in liver; however, the mechanisms by which it contributes to liver injury remain uncertain. We induced steatohepatitis in zebrafish embryos using thioacetamide (TAA). TUNEL assay revealed significant increasing of apoptosis in liver after 5 days post fertilization and the increasing of apoptosis was observed to be associated with the up-regulation of apoptotic genes such as, bad, bax, P-38a, caspase-3 and 8, and JNK-1. Histological sections by oil red O stain showed the accumulation of fatty droplets which causes the pushing of the nucleus towards one side. Up-regulation of steatosis markers such as, ACC, adiponectin, PTL, CEBP- and , SREBP-1 was also observed. Furthermore, the elevation of glutathione peroxidase in TAA treated embryos indicated that TAA induces lipid peroxidation which leads to causes liver damage. Zebrafish has already been considered as a good human disease model and in this context; TAA-treated zebrafish may serve as a good animal model to study the molecular pathogenesis of steatohepatitis. Moreover, non-availability of specific drugs to prevent steatohepatitis, this animal model may serve as a powerful preclinical platform to study the therapeutic strategies and for evaluating chemoprevention strategies for this disease.  相似文献   
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