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91.
Abstract We used a network of 20 carbon dioxide- and octenol-supplemented light traps to sample adult mosquitoes throughout Russell Island in southern Moreton Bay, south-east Queensland. Between February and April 2001, an estimated 1365 564 adult female mosquitoes were collected. In contrast to an average catch of 9754 female mosquitoes per trap night on Russell Island, reference traps set on Macleay Island and on the mainland returned average catches of 3172 and 222, respectively. On Russell Island, Ochlerotatus vigilax (Skuse), Coquillettidia linealis (Skuse), Culex annulirostris Skuse and Verrallina funerea (Theobald), known or suspected vectors of Ross River (RR) and/or Barmah Forest (BF) viruses, comprised 89.6% of the 25 taxa collected. When the spatial distributions of the above species were mapped and analysed using local spatial statistics, all were found to be present in highest numbers towards the southern end of the island during most of the 7 weeks. This indicated the presence of more suitable adult harbourage sites and/or suboptimal larval control efficacy. As immature stages and the breeding habitat of Cq. linealis are as yet undescribed, this species in particular presents a considerable impediment to proposed development scenarios. The method presented here of mapping the numbers of mosquitoes throughout a local government area allows specific areas that have high vector numbers to be defined.  相似文献   
92.
Isospora dawadimiensis n. sp. is described from the jerboa, Jaculus jaculus, from Dawadimi, Saudi Arabia. Sporulated oocysts of I. dawadimiensis n. sp. were ovoidal or nearly subspherical 22–26.5 times 20.5–22 μm (24.4 times 21.4 μm). Oocyst wall had one layer. Micropyle, oocyst residuum, and polar granule were absent. Sporocysts were ellipsoid 12–16.5 times 9–10.5 μm (14.6 times 9.9 μm). Sporocyst residuum was present. The sporocysts lack a Stieda body. Sporozoites 8–11 times 2–3 μm (10 times 2.6 μm) were sausage-shaped, slightly curved, and tapered at one end.  相似文献   
93.

Introduction

Atenolol, a commonly prescribed β blocker for hypertension, is also associated with adverse cardiometabolic effects such as hyperglycemia and dyslipidemia. Knowledge of the mechanistic underpinnings of these adverse effects of atenolol is incomplete.

Objective

We sought to identify biomarkers associated with risk for these untoward effects of atenolol. We measured baseline blood serum levels of acylcarnitines (ACs) that are involved in a host of different metabolic pathways, to establish associations with adverse cardiometabolic responses after atenolol treatment.

Methods

Serum samples from Caucasian hypertensive patients (n = 224) who were treated with atenolol in the Pharmacogenomic Evaluation of Antihypertensive Responses (PEAR) study were interrogated using a quantitative LC/MS assay for a large number of unique ACs in serum. For the 23 ACs that were detected in serum from ≥80 % of all patients, we conducted linear regression for changes in cardiometabolic factors with baseline AC levels, baseline cardiometabolic factors, age, sex, and BMI as covariates. For the 5 ACs that were detected in serum from 20 to 79 % of the patients, we similarly modeled changes in cardiometabolic factors, but with specifying the AC as present/absent in the regression.

Results

Among the 28 ACs, the presence (vs. absence) of arachidonoyl-carnitine (C20:4) was significantly associated with increased glucose (p = 0.0002), and was nominally associated with decreased plasma HDL-C (p = 0.017) and with less blood pressure (BP) lowering (p = 0.006 for systolic BP, p = 0.002 for diastolic BP), after adjustment.

Conclusion

Serum level of C20:4 is a promising biomarker to predict adverse cardiometabolic responses including glucose and poor antihypertensive response to atenolol.
  相似文献   
94.
Galectins, beta-galactoside-binding lectins, are extensively distributed in the animal kingdom and share some basic molecular properties. Galectin-3, a member of this family, is generally associated with differentiation, morphogenesis, and metastasis. In this study, galectin-3 was isolated from ovine placental cotyledons round the middle of the gestation period by lactose extraction followed by affinity chromatography on lactosyl-agarose, and separated from galectin-1 by size exclusion chromatography on a Superose 12 column. Under native conditions this lectin behaved as a monomer with an apparent molecular weight of approximately 29,000 and an isoelectric point of 9.0. The partial amino acid sequence of the peptides obtained by tryptic digestion of this protein followed by HPLC separation showed striking homology with other members of the galectin-3 subfamily. Furthermore, ovine placental galectin-3 exhibited specific mitogenic activity toward rat spleen mononuclear cells. Besides, this protein strongly reacted with a rabbit antiserum raised against a chicken galectin. Results obtained by Western blot analysis showed that its expression was greatly decreased in term placenta with respect to the middle of the gestation period, suggesting a regulated expression throughout development.   相似文献   
95.
Continuous ethanol fermentations were performed in duplicate for 60 days withZymomonas mobilis ATCC 331821 orSaccharomyces cerevisiae ATCC 24859 in packed-bed reactors with polypropylene or plastic composite-supports. The plastic composite-supports used contained polypropylene (75%) with ground soybean-hulls (20%) and zein (5%) forZ. mobilis, or with ground soybean-hulls (20%) and soybean flour (5%) forS. cerevisiae. Maximum ethanol productivities of 536 gL–1 h–1 (39% yield) and 499 gL–1 h–1 (37% yield) were obtained withZ. mobilis on polypropylene and plastic composite-supports of soybean hull-zein, respectively. ForZ. mobilis, and optimal yield of 50% was observed at a 1.92h–1 dilution rate for soybean hull-zein plastic composite-supports with a productivity of 96gL–1h–1, whereas with polypropylene-supports the yield was 32% and the productivity was 60gL–1h–1. With aS. cerevisiae fermentation, the ethanol production was less, with a maximum productivity of 76gL–1h–1 on the plastic composite-support at a 2.88h–1 dilution rate with a 45% yield. Polypropylene-support bioreactors were discontinued due to reactor plugging by the cell mass accumulation. Support shape (3-mm chips) was responsible for bioreactor plugging due to extensive biofilm development on the plastic composite-supports. With suspensionculture continuous fermentations in continuously-stirred benchtop fermentors, maximum productivities of 5gL–1h–1 were obtained with a yield of 24 and 26% withS. cerevisiae andZ. mobilis, respectively. Cell washout in suspensionculture continuous fermentations was observed at a 1.0h–1 dilution rate. Therefore, for continuous ethanol fermentations, biofilm reactors out-performed suspension-culture reactors, with 15 to 100-fold higher productivities (gL–1h–1) and with higher percentage yields forS. cerevisiae andZ. mobilis, respectively. Further research is needed with these novel supports to evaluate different support shapes and medium compositions that will permit medium flow, stimulate biofilm formation, reduce fermentation costs, and produce maximum yields and productivities.This is Journal Paper No. J-16357 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 3253  相似文献   
96.
Biofilms are a natural form of cell immobilization that result from microbial attachment to solid supports. Biofilm reactors with polypropylene composite-supports containing up to 25% (w/w) of various agricultural materials (corn hulls, cellulose, oat hulls, soybean hulls or starch) and nutrients (soybean flour or zein) were used for ethanol production. Pure cultures ofZymomonas mobilis, ATCC 31821 orSaccharomyces cerevisiae ATCC 24859 and mixed cultures with either of these ethanol-producing microorganisms and the biofilm-formingStreptomyces viridosporus T7A ATCC 39115 were evaluated. An ethanol productivity of 374g L–1 h–1 (44% yield) was obtained on polypropylene composite-supports of soybean hull-zein-polypropylene by usingZ. mobilis, whereas mixed-culture fermentations withS. viridosporus resulted in ethanol productivity of 147.5 g L–1 h–1 when polypropylene composite-supports of corn starch-soybean flour were used. WithS. cerevisiae, maximum productivity of 40 g L–1 h–1 (47% yield) was obtained on polypropylene composite-supports of soybean hull-soybean flour, whereas mixed-culture fermentation withS. viridosporus resulted in ethanol productivity of 190g L–1 h–1 (35% yield) when polypropylene composite-supports of oat hull-polypropylene were used. The maximum productivities obtained without supports (suspension culture) were 124 g L–1 h–1 and 5 g L–1 h–1 withZ. mobilis andS. cerevisiae, respectively. Therefore, forZ. mobilis andS. cerevisiae, ethanol productivities in biofilm fermentations were three- and eight-fold higher than suspension culture fermentations, respectively. Biofilm formation on the chips was detected by weight change and Gram staining of the support material at the end of the fermentation. The ethanol production rate and concentrations were consistently greater in biofilm reactors than in suspension cultures.This is Journal Paper No. J-16356 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa. Project No. 3253  相似文献   
97.
不孕不育患者解脲脲原体菌株血清型别的检测   总被引:2,自引:0,他引:2  
本文以解脲脲原体标准菌株1-14型免疫家获得UU1-14型抗血清。用IDT法对48株自不孕不育患者分离的地方株作分型试验。结果在1.2.4.5.6.7.8和12血八个清型中出现强阳性反应,其中4型最多。另有4株混合型。对四种血清型无反应。  相似文献   
98.
A phylogenetic analysis of chaperonin (heat shock protein 60) sequences from prokaryotes and eukaryotes indicated that a single gene duplication event in the common ancestor of Mycobacterium tuberculosis, M. leprae, and Streptomyces albus gave rise to the duplicate chaperonin genes found in these species (designated HSP65 and GroEL in the mycobacterial species). Comparison of rates of synonymous and nonsynonymous nucleotide substitution in different gene regions suggested that the 5' end of the HSP65 gene was homogenized by an ancient recombination event between M. tuberculosis and M. leprae. In S. albus, the two duplicated chaperonin genes have evolved at essentially the same rate. In both M. tuberculosis and M. leprae, however, the GroEL gene has evolved considerably more rapidly at nonsynonymous nucleotide sites than has the HSP65 gene. Because this difference is not seen at synonymous sites, it must be due to a difference in selective constraint on the proteins encoded by the two genes, rather than to a difference in mutation rate. The difference between GroEL and HSP65 is striking in regions containing epitopes recognized by T cells of the vertebrate host; in certain cross-reactive epitopes conserved across all organisms, nonsynonymous sites in GroEL have evolved twice as fast as those in HSP65. It is suggested that these differences are correlated with differences in the way in which the duplicate chaperonins of M. tuberculosis and M. leprae interact with the host immune system.   相似文献   
99.
The long (4.6-kb) A+T region of Drosophila melanogaster mitochondrial DNA has been cloned and sequenced. The A+T region is organized in two large arrays of tandemly repeated DNA sequence elements, with nonrepetitive intervening and flanking sequences comprising only 22% of its length. The first repeat array consists of five repeats of 338-373 bp. The second consists of four intact 464-bp repeats and a fifth partial repeat of 137 bp. Three DNA sequence elements are found to be highly conserved in D. melanogaster and in several Drosophila species with short A+T regions. These include a 300-bp DNA sequence element that overlaps the DNA replication origin and two thymidylate stretches identified on opposite DNA strands. We conclude that the length heterogeneity observed in the A+T regulatory region in mitochondrial DNAs from the genus Drosophila results from the expansion (and contraction) of the number of repeated DNA sequence elements. We also propose that the 300-bp conserved DNA sequence element, in conjunction with another primary sequence determinant, perhaps the adjacent thymidylate stretch, functions in the regulation of mitochondrial DNA replication.   相似文献   
100.
A simple microRNA (miRNA) aptasensor has been developed combining the conformational switch of a streptavidin aptamer and isothermal strand displacement amplification. In the presence of its target miRNA, the allosteric molecular beacon (aMB) probe immobilized on the plate can be ‘switched on' and release the streptavidin aptamer. At the same time, Klenow fragment (3′→5′ exo‐) is utilized to initiate DNA‐strand displacement, which starts the target recycling process. Based on the aptamer' high binding affinity and subsequent catalytic chemiluminescence (CL) detection, this CL strategy is highly specific in distinguishing mature miRNAs in same family. It exhibits a dynamic range of four orders of magnitude with a detection limit of 50 fM, and shows great potential for miRNA‐related clinical practices and biochemical research.  相似文献   
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