Search results for "Specificity."

Aquatic pollution may favor the success of the invasive species A. franciscana

2015

The genus Artemia consists of several bisexual and parthenogenetic sibling species. One of them, A. franciscana, originally restricted to the New World, becomes invasive when introduced into ecosystems out of its natural range of distribution. Invasiveness is anthropically favored by the use of cryptobiotic eggs in the aquaculture and pet trade. The mechanisms of out-competition of the autochthonous Artemia by the invader are still poorly understood. Ecological fitness may play a pivotal role, but other underlying biotic and abiotic factors may contribute. Since the presence of toxicants in hypersaline aquatic ecosystems has been documented, our aim here is to study the potential role of an…

Detection of oxidative mutagenesis by isoniazid and other hydrazine derivatives in Escherichia coli WP2 tester strain IC203, deficient in OxyR: stron…

1998

Abstract Strain IC203, deficient in the OxyR function, was sensitive to both cytotoxic and mutagenic effects of isoniazid (INH) whereas its parent, WP2 uvrA /pKM101, was resistant to these effects. Four other hydrazine compounds, hydrazine hydrate (HZH), phenylhydrazine (PHZ), hydralazine (HLZ) and nialamide (NLD), were mutagenic in WP2 uvrA /pKM101. Increases in mutagenicity were observed in IC203 for HZH and PHZ but not for HLZ and NLD. Growth inhibition zones by HZH, PHZ and NLD were larger in IC203 than in WP2 uvrA /pKM101. The enhancements in the effects of INH, HZH and PHZ in IC203 with respect to its oxyR + parent are considered to be caused by the production of reactive oxygen speci…

Colour-flow-mapping in patients with ventricular septal defect.

1991

Carbohydrate binding specificity and purification by biospecific affinity chromatography of Ascidiamalaca traust. Hemagglutinins

1982

The carbohydrate specificities of Ascidia malaca serum hemagglutinins were determined by hemagglutination inhibition tests. Analysis of agglutinins against rabbit and human A, B, O erythrocytes suggests that the size of the combining site corresponds to a disaccharide with a specificity for saccharides containing a D-galacto configuration (D-melibiose, D-raffinose, D-galactose, alpha-lactose, lactulose, L-arabinose). No anomeric specificity was observed with oligosaccharides. Hydroxyl groups probably involved in hydrogen-bond formation with agglutinin binding site, were identified as carbons C2, C4, C5 and C6 of D-galactose. Absorption experiments showed that two distinct agglutinins with s…

Gene expression specificity of the mussel antifungal mytimycin (MytM)

2011

Abstract We previously reported the nucleotide sequences and diversity of mytimycin (MytM) from the Mediterranean mussel, Mytilus galloprovincialis. Using real-time PCR (q-PCR), we observed that the MytM gene was mainly expressed in circulating hemocytes and to a less extent in the mantle. In vivo challenge with bacteria or with the yeast, Candida albicans, did not increase the expression as measured by q-PCR in hemocytes. By contrast, injection of the filamentous fungus, Fusarium oxysporum, induced a sudden and strong increase of expression at 9h p.i. (stimulation index of 25.7 ± 2.1). Optimum stimulating dose was 104 spores of F. oxysporum per mussel. In the same samples, AMP mytilin and …

Prothrombinase-Induced Clotting Time Assay for Determination of the Anticoagulant Effects of Unfractionated and Low-Molecular-Weight Heparins, Fondap…

2008

The prothrombinase-induced clotting time assay (PiCT, Pentapharm, Basel, Switzerland) is a clotting assay sensitive to factor Xa and factor IIa inhibitors. It is based on the addition of factor Xa and snake venom RVV-V (Russell viper venom factor V activator) specifically activating factor V and phospholipids to platelet-poor plasma. Following an incubation time, the mixture is recalcified and the clotting time is determined. An almost linear dose-response and high sensitivity of the assay for unfractionated heparin (UFH), low-molecular-weight heparins (LMWHs), r-hirudin, and argatroban was found. Fondaparinux showed a nonlinear dose-response. By using ex vivo samples, the following Pearson…

Ligase Chain Reaction (LCR®) assay for semi-quantitative detection of HBV DNA in mononuclear leukocytes of patients with chronic hepatitis B

1996

Summary. A ligase chain reaction (LCR®)-based approach to detect hepatitis B virus (HBV) DNA in peripheral blood mononuclear cells (PBMC) is described. Using this new amplification technique, we determined semi-quantitatively the amount of a short HBV S-gene fragment in PBMC lysates of 25 patients with different forms of chronic hepatitis (group A (n= 8), hepatitis B s antigen (HBsAg)+/hepatitis B e antigen (HBeAg)+; group B (n= 9), HBsAg+/HBeAg-; group C (n= 8), HBsAg-/HBeAg-). The LCR results were compared with the findings obtained with polymerase chain reaction (PCR) amplification of three distinct HBV gene regions (preS1/2, S and C) and related to the serological profiles of the patien…

Semiquantitative assessment of pre-core stop-codon mutant and wildtype hepatitis B virus during the course of chronic hepatitis B using a new PCR-bas…

1996

In most patients with chronic hepatitis B positive for antibodies (anti-HBe) to HBe antigen (HBeAg), a pre-core mutant hepatitis B virus (HBV) with a point-mutation at nt. 1896 can be isolated. Clinical significance of the mutant virus in chronic hepatitis B is not proven yet, and screening of large numbers of sera during different clinical courses of numerous patients is necessary. We therefore aimed to develop a fast and reliable assay, that allows to discriminate wildtype from nt. 1896 G-->A mutant HBV and to determine the ratio of mutant and wildtype HBV in patients' sera. A mutation specific polymerase chain reaction (ms PCR) with new primers served to distinguish nt. 1896 G-->A mutant…

Quantitation of HCV-replication using one-step competitive reverse transcription-polymerase chain reaction and a solid phase, colorimetric detection …

1994

A solid phase assay for the colorimetric detection of competitively amplified HCV-cDNA has been established and used to investigate clinical samples from patients with chronic hepatitis. The assay is based on the reduction in the amplification of an hepatitis C virus-related competitor molecule by wild-type hepatitis C virus during polymerase chain reaction. The internal standard contains a lac operator sequence, allowing the amount of amplified competitor to be determined using a lac I-repressor/beta-galactosidase fusion protein. The reduction in the amplification of competitor is dependent upon the concentration of HCV-RNA in the original sample. External hepatitis C virus wild-type stand…

Computer-aided detection of cerebral microbleeds in susceptibility-weighted imaging.

2014

Susceptibility-weighted imaging (SWI) is recognized as the preferred MRI technique for visualizing cerebral vasculature and related pathologies such as cerebral microbleeds (CMBs). Manual identification of CMBs is time-consuming, has limited reliability and reproducibility, and is prone to misinterpretation. In this paper, a novel computer-aided microbleed detection technique based on machine learning is presented: First, spherical-like objects (potential CMB candidates) with their corresponding bounding boxes were detected using a novel multi-scale Laplacian of Gaussian technique. A set of robust 3-dimensional Radon- and Hessian-based shape descriptors within each bounding box were then ex…