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91.
Tutulan-Cunita AC Mikoshi M Mizunuma M Hirata D Miyakawa T 《Genes to cells : devoted to molecular & cellular mechanisms》2005,10(5):409-420
Multidrug resistance ABC transporter Pdr5p of Saccharomyces cerevisiae is particularly important due to its ability to export a wide range of unrelated substrates. To clarify its function, we generated Pdr5p mutants by random mutagenesis and screened for mutants with altered drug specificity in vivo by using 5 drug compounds. Nine point mutations that caused significant changes in drug specificity distributed throughout the length of Pdr5p, namely, in the extracellular, transmembrane or cytoplasmic regions of the transporter. We then investigated their effects upon drug resistance, using 36 chemically related or distinct substrates. From this study, overall geometry of the Pdr5p was suggested to contribute in acquiring the enormous range of drug specificity. Based on their ability to inhibit the growth of the mutant strains, the 36 tested drugs were classified into: drugs to which the mutants responded differently (Group 1), drugs to which all the mutants showed sensitivity (Group 2), and drugs to which all the mutants exhibited resistance (Group 3). The ability of the compounds to be partitioned to the plasma membrane seemed an important factor for recognition by Pdr5p. 相似文献
92.
Comparative Evaluation of Ligation-Mediated PCR and Spoligotyping as Screening Methods for Genotyping of Mycobacterium tuberculosis Strains 总被引:3,自引:0,他引:3 下载免费PDF全文
Stefano Bonora M. Cristina Gutierrez Giovanni Di Perri Francesca Brunello Benedetta Allegranzi Marco Ligozzi Roberta Fontana Ercole Concia Veronique Vincent 《Journal of clinical microbiology》1999,37(10):3118-3123
Spoligotyping has been suggested as a screening test in multistep genotyping of Mycobacterium tuberculosis strains. Relying on restriction fragment length polymorphism (RFLP) analysis with IS6110 (IS6110 RFLP analysis) as a "gold standard," we performed a comparative evaluation of spoligotyping and ligation-mediated PCR (LMPCR), a recently described PCR-based typing method, as rapid screening tests for fingerprinting of 158 M. tuberculosis strains collected in Verona, Italy. LMPCR seemed to be comparable to spoligotyping in terms both of feasibility with rapidly extracted DNA and of generation of software-analyzable images. Moreover, LMPCR grouped considerably fewer strains than spoligotyping (38 versus 67%) and was found to reduce the cluster overestimation rate (26.3 versus 58%) and to give a better discriminatory index (0.992 versus 0.970) compared to spoligotyping. In our geographical region, where there was no evidence of clustered strains carrying fewer than six IS6110 copies, LMPCR was found to be more discriminatory than spoligotyping. We also evaluated two models of three-step typing strategies, involving the use of spoligotyping and LMPCR as screening methods and IS6110 RFLP analysis as a further supporting test. LMPCR proved to be a more effective first-step test than spoligotyping, significantly reducing the need for subtyping. LMPCR should be considered an alternative to spoligotyping as a rapid screening method for M. tuberculosis fingerprinting, particularly in areas with a low prevalence of M. tuberculosis strains carrying few copies of IS6110. 相似文献
93.
d'Amati G Bagattin A Bauce B Rampazzo A Autore C Basso C King K Romeo MD Gallo P Thiene G Danieli GA Nava A 《Human pathology》2005,36(7):761-767
We report on a family with a history of sudden death and effort-induced polymorphic ventricular arrhythmias. The index case was a 17-year-old boy who died suddenly and at postmortem had evidence of fibrofatty replacement in the right ventricular free wall, consistent with arrhythmogenic right ventricular cardiomyopathy, as well as calcium phosphate deposits within the myocytes. A molecular genetics investigation carried out in the paraffin-embedded myocardium of the subject and in blood samples of family members disclosed a missense mutation in exon 3 (230C-->T; A77V) of the cardiac ryanodine receptor type 2 gene. The carriers showed effort-induced polymorphic ventricular tachycardia in the setting of normal resting electrocardiogram and trivial echocardiographic abnormalities, consistent with catecholaminergic polymorphic ventricular tachycardia. The observation of both arrhythmogenic right ventricular cardiomyopathy type 2 and catecholaminergic polymorphic ventricular tachycardia in the same family suggests that the two entities might correspond to different degrees of phenotypic expression of the same disease. This experience underscores the importance of a precise autopsy diagnosis in the case of sudden cardiac death, including molecular genetics, and the mission of pathologists to guide further clinical investigation of family members. 相似文献
94.
Jagdish Butany Manmeet S. Ahluwalia Craig Munroe Cristina Fayet Christina Ahn Patrick Blit Charis Kepron Roberto J. Cusimano Richard L. Leask 《Cardiovascular pathology》2003,12(6):322-344
Mechanical heart value prostheses have been in use since the 1950s. Many prostheses have been used for a while and then discontinued. Today, there are a large number and variety of prostheses in use and an even larger variety that are in place in patients. These may be explanted at any time for a number of reasons. It is essential for the practicing pathologist to be able to identify the prosthesis and be aware of some of its reported complications and modes of failure. This article, and a second one on bioprosthetic heart valves, is designed as a ready reference guide to heart valve prostheses, their important identifying features, their common complications, and modes of failure. It should help in the accurate identification of explanted prosthetic valves and more definitive reports. This accuracy of identification as well as tracking of abnormalities noted will, we hope, permit the identification of new failure modes and the recording of causes of failure of new (or even modified) prosthetic heart valves. 相似文献
95.
Comparative evaluation of the new version of the INNO-LiPA Mycobacteria and genotype Mycobacterium assays for identification of Mycobacterium species from MB/BacT liquid cultures artificially inoculated with Mycobacterial strains 总被引:2,自引:0,他引:2 下载免费PDF全文
Padilla E González V Manterola JM Pérez A Quesada MD Gordillo S Vilaplana C Pallarés MA Molinos S Sánchez MD Ausina V 《Journal of clinical microbiology》2004,42(7):3083-3088
The performance of two DNA line probe assays, a new version of INNO-LiPA Mycobacteria (Innogenetics, Ghent, Belgium) and the GenoType Mycobacterium (Hain Diagnostika, Nehren, Germany), were evaluated for identification of mycobacterial species isolated from liquid cultures. Both tests are based on a PCR technique and designed for simultaneous identification of different mycobacterial species by reverse hybridization and line probe technology. The INNO-LiPA Mycobacteria v2 targeting the 16S-23S rRNA gene spacer region was developed for the simultaneous identification of 16 different mycobacterial species. The GenoType Mycobacterium, which targets the 23S rRNA gene, allows simultaneous identification of 13 mycobacterial species. Both tests were evaluated on 110 mycobacterial strains belonging to 22 different mycobacterial species (20 reference strains, 83 clinical strains, and 4 Mycobacterium kansasii strains isolated from tap water) that were previously inoculated into MB/BacT bottles. The sensitivity of both methods, defined as the number of positive results obtained with the Mycobacterium genus probe together with an interpretable result on the number of samples tested was 110 of 110 (100%) for INNO-LiPA and 102 of 110 (92.7%) for GenoType. For samples with interpretable results, INNO-LiPA was able to correctly identify 109 of 110 samples (99.1%), whereas the GenoType correctly identified 100 of 102 samples (98.0%). Both tests were easy to perform, rapid, and reliable when applied to mycobacterial identification directly from MB/BacT bottles. 相似文献
96.
Fernando Gabriel Chirdo María Cristina Añón Carlos Alberto Fossati 《Food and Agricultural Immunology》1998,10(2):143-155
Optimization of three enzyme immunoassays of very high sensitivity using three antiprolamin monoclonal antibodies (MAbs) (13B4, 11C4 and 12A1) is presented here. These MAbs are specific for those prolamins toxic for coeliac patients, as determined by immunoblotting analysis. Biotinylated MAbs were used in two of the assays. In a competitive ELISA, the binding of each biotinylated MAb to a gliadin‐coated solid phase was inhibited by gliadin in the fluid phase. The best result was obtained using the biotinylated MAbl3B4 (detection limit: 20 ng ml?1). With regard to capture ELISA, we tested the performance of the three MAbs. In this sandwich ELISA, the MAb used for antigenic capture was the same as that used as secondary biotinylated antibody. The MAbl2Al had the best performance (detection limit: 1 ng ml?1). The use of biotin‐labelled gliadin in a quantitative immunoassay with a detection limit of 5 ng ml?1 is also reported. This assay involves an antigenic capture using the MAbl2Al followed by a competition between biotinylated and non‐biotinylated gliadin. We have found the use of the streptavidin‐biotin interaction as signal amplification system to be very useful. This technique, as far as we know, has not been previously reported for gliadin quantification. 相似文献
97.
98.
Montano SM Sanchez JL Laguna-Torres A Cuchi P Avila MM Weissenbacher M Serra M Viñoles J Russi JC Aguayo N Galeano AH Gianella A Andrade R Arredondo A Ramirez E Acosta ME Alava A Montoya O Guevara A Manrique H Sanchez JL Lama JR de la Hoz F Sanchez GI Ayala C Pacheco ME Carrion G Chauca G Perez JJ Negrete M Russell KL Bautista CT Olson JG Watts DM Birx DL Carr JK;South American HIV Molecular Surveillance Working Group 《Journal of acquired immune deficiency syndromes (1999)》2005,40(1):57-64
HIV cross-sectional studies were conducted among high-risk populations in 9 countries of South America. Enzyme-linked immunosorbent assay screening and Western blot confirmatory testing were performed, and env heteroduplex mobility assay genotyping and DNA sequencing were performed on a subset of HIV-positive subjects. HIV prevalences were highest among men who have sex with men (MSM; 2.0%-27.8%) and were found to be associated with multiple partners, noninjection drug use (non-IDU), and sexually transmitted infections (STIs). By comparison, much lower prevalences were noted among female commercial sex workers (FCSWs; 0%-6.3%) and were associated mainly with a prior IDU and STI history. Env subtype B predominated among MSM throughout the region (more than 90% of strains), whereas env subtype F predominated among FCSWs in Argentina and male commercial sex workers in Uruguay (more than 50% of strains). A renewed effort in controlling STIs, especially among MSM groups, could significantly lessen the impact of the HIV epidemic in South America. 相似文献
99.
100.
Analysis of IFN-kappa expression in pathologic skin conditions: downregulation in psoriasis and atopic dermatitis. 总被引:3,自引:0,他引:3
Claudia Scarponi Bernardetta Nardelli David W Lafleur Paul A Moore Stefania Madonna Ornella De Pità Giampiero Girolomoni Cristina Albanesi 《Journal of interferon & cytokine research》2006,26(3):133-140
Interferon-kappa (IFN-kappa) is a type I IFN expressed by keratinocytes, monocytes and dendritic cells (DCs). In human keratinocytes, it is produced in response to double-stranded RNA (dsRNA) and other IFNs and protects from viral infections. In monocytes and DCs, IFN-kappa induces tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) and inhibits lipopolysaccharide (LPS)-induced IL-12. In this study, we evaluated IFN-kappa expression in skin lesions of patients with common immune-mediated inflammatory disorders using immunohistochemical techniques. IFN-kappa was not detectable in healthy skin but was strongly expressed in allergic contact dermatitis and lichen planus-affected skin. IFN-kappa was localized mainly in basal and suprabasal keratinocytes and in some leukocytes infiltrating the dermis. In contrast, IFN-kappa expression in psoriatic or atopic dermatitis (AD) pidermis was weak and detectable in only 2 of 5 patients examined. Consistently, cultured keratinocytes and monocytes obtained from psoriatic and AD patients expressed null or low levels of IFN-kappa in response to IFN-gamma, which strongly upregulates IFN-kappa in normal keratinocytes. IFN-kappa accumulated in keratinocyte cytoplasm and plasma membrane, and only limited amounts were released extracellularly. Soluble IFN-kappa did not influence keratinocyte proliferation or chemokine and membrane molecule expression, and only its membrane-associated form activated IFN-stimulated response element (ISRE) signaling. Given the difference in IFN-kappa expression levels in the skin disorders examined, IFN-kappa presence or deficiency might have different pathogenetic consequences depending also on other disease-specific intrinsic alterations. 相似文献