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BackgroundCurrently, there are no biomarkers that can predict the incidence of dengue shock and/or organ failure, although the early identification of risk factors is important in determining appropriate management to reduce mortality. Therefore, we sought to determine the factors associated with dengue shock and/or organ failure and to evaluate the prognostic value of serum procalcitonin (PCT) and peripheral venous lactate (PVL) levels as biomarkers of dengue shock and/or organ failure.Conclusions/SignificancePCT ≥0.7 ng/mL and PVL ≥2.5 mmol/L were independently associated with dengue shock and/or organ failure. The combination of PCT and PVL levels could be used as prognostic biomarkers for the prediction of dengue shock and/or organ failure.  相似文献   
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Phytoremediation is widely promoted as a cost-effective technology for treating heavy metal and total petroleum hydrocarbon (TPH) co-contaminated soil. This study investigated the concurrent removal of TPHs and Pb in co-contaminated soil (27,000 mg kg?1 TPHs, 780 mg kg?1 Pb) by growing Siam weed (Chromolaena odorata) in a pot experiment for 90 days. There were four treatments: co-contaminated soil; co-contaminated soil with C. odorata only; co-contaminated soil with C. odorata and Micrococcus luteus inoculum; and co-contaminated soil with M. luteus only. C. odorata survived and grew well in the co-contaminated soil. C. odorata with M. luteus showed the highest Pb accumulation (513.7 mg kg?1) and uptake (7.7 mg plant?1), and the highest reduction percentage of TPHs (52.2%). The higher TPH degradation in vegetated soils indicated the interaction between the rhizosphere microorganisms and plants. The results suggested that C. odorata together with M. luteus and other rhizosphere microorganisms is a promising candidate for the removal of Pb and TPHs in co-contaminated soils.  相似文献   
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BackgroundIn falciparum malaria sequestration of erythrocytes containing mature forms of Plasmodium falciparum in the microvasculature of vital organs is central to pathology, but quantitation of this hidden sequestered parasite load in vivo has not previously been possible. The peripheral blood parasite count measures only the circulating, relatively non-pathogenic parasite numbers. P. falciparum releases a specific histidine-rich protein (PfHRP2) into plasma. Quantitative measurement of plasma PfHRP2 concentrations may reflect the total parasite biomass in falciparum malaria.ConclusionPlasma PfHRP2 concentrations may be used to estimate the total body parasite biomass in acute falciparum malaria. Severe malaria results from extensive sequestration of parasitised erythrocytes.  相似文献   
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A method for the quantitative analysis of pyruvate and acetate groups in polysaccharides has been developed, using HPLC on a cation exchange resin in the protonated form and u.v. detection at 210 nm. Procedures for release of acetate and pyruvate from polysaccharides are described.In the case of xanthan gum, most of the pyruvate is removed if the sample is autoclaved in water during preparation, and about 25% is lost if autoclaved in 0·1 m sodium chloride solution.  相似文献   
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Pulmonary hemorrhage is an increasing cause of death of leptospirosis patients. Bacterial collagenase has been shown to be involved in lung hemorrhage induced by various infectious agents. According to Leptospira whole genome study, colA, a gene suggested to code for bacterial collagenase has been identified. We investigated colA gene expression in lung tissues of Leptospira infected hamsters. Golden Syrian Hamsters were injected intraperitoneally with Leptospira interrogans serovar Pyrogenes. The hamsters were sacrificed on days 3, 5 and 7 post-infection and lung tissues were collected for histological examination and RNA extraction. Lung pathologies including atelectasis and hemorrhage were observed. Expression of colA gene in lung tissues was demonstrated by both RT-PCR and real time PCR. In addition, ColA protein was cloned and the purified protein could react with sera from leptospirosis patients. Leptospira ColA protein may play a role in Leptospira survival or pathogenesis in vivo. Its reaction with leptospirosis sera suggests that this protein is immunogenic and could be another candidate for vaccine development.  相似文献   
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One new pyrrolidine derivative, asperidine A (1), and two new piperidine derivatives, asperidines B (2) and C (3), were isolated from the soil-derived fungus Aspergillus sclerotiorum PSU-RSPG178 together with two known alkaloids. Compound 3 possessed an unprecedented 7-oxa-1-azabicyclo[3.2.1]octane skeleton with four chiral centers. Their structures were determined by spectroscopic evidence. The absolute configurations of compounds 2 and 3 were established using Mosher’s method and further confirmed for compound 3 by X-ray crystallographic data. Compound 2 dose-dependently inhibited the CFTR-mediated chloride secretion in T84 cells with an IC50 value of 0.96?μM whereas 3 displayed the same activity with the IC50 value of 58.62?μM. Compounds 2 and 3 also significantly reduced intracellular ROS under both normal and H2O2-treated conditions compared with their respective controls in a dose-dependent manner without cytotoxic effect on Caco-2 cells. In addition, compound 3 was inactive against noncancerous Vero cells whereas compound 2 was considered to be inactive with the IC50 value of >10?μM.  相似文献   
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The maintenance of soil organic matter (SOM) and the balancing of nutrient flows into and out of the rainfed rice cropping systems in Northeast Thailand is of paramount importance to arresting the decline in soil fertility and crop yields. A system where small applications of leaf litters from locally grown trees are applied annually to rice paddy soils prior to transplanting is described. The annual application of 1500 kg/ha of Cajanus cajan, Acacia auriculiformis, Phyllanthus taxodifolius and Samanea saman for five seasons resulted in increases in rice grain yield of 48, 35, 32 and 23% above the no-leaf litter control, respectively. Average annual nutrient inputs from the leaf litters, in kg/ha, ranged from 62.7 N, 3.9 P, 17.9 K, and 3.5 S for Cajanus cajan to 24.5 N, 1.5 P, 8.1 K and 2.0 S for Acacia auriculiformis. Nutrient balances, determined by the difference between the inputs (fertiliser and added leaf litters) and outputs (grain and straw) indicated net positive N and P balances of up to 457 and 60 kg/ha. respectively, after five seasons of leaf litter applications. Sulfur and potassium balances resulted in net deficits of up to −3 and −52 kg S and K/ha, respectively, where no leaf litter was applied and rice straw was removed following harvest. Calculated apparent nutrient recoveries reflected the decomposition rate of the added residues and were highest for P and K, reflecting their higher soil residual value than mobile nutrients such as N and S. Sustainable farming systems will require that crop yields are stable through the maintenance of soil fertility and the balance of nutrients in the system. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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We aimed to clarify phylogenetic relationships within the pantropical genus Diospyros (Ebenaceae sensu lato), and ascertain biogeographical patterns in the New Caledonian endemic species. We used DNA sequences from eight plastid regions (rbcL, atpB, matK, ndhF, trnK intron, trnL intron, trnL-trnF spacer, and trnS-trnG spacer) and included 149 accessions representing 119 Diospyros species in our analysis. Results from this study confirmed the monophyly of Diospyros with good support and provided a clearer picture of the relationships within the genus than in previous studies. Evidence from phylogenetic analyses suggests that Diospyros colonized New Caledonia multiple times. The four lineages of Diospyros in New Caledonia also differ in their degree of diversification. The molecular data indicate that one lineage is paleoendemic and derived from an ancient Australian species. The other three lineages are more closely related to several Southeast Asian species; two of them are neoendemics, and one has radiated rapidly and recently.  相似文献   
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