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Endonuclease Digestion (endonuclease + digestion)
Kinds of Endonuclease Digestion Selected AbstractsIdentification of cyanobacteria and their toxigenicity in environmental samples by rapid molecular analysisENVIRONMENTAL TOXICOLOGY, Issue 6 2001Judith A. Baker Abstract We report molecular analyses which identify cyanobacterial strains present in environmental samples. These analyses do not require the isolation and culture of strains. Identification of cyanobacteria used the polymerase chain reaction (PCR), based on the phycocyanin operon. Differentiation was either by restriction endonuclease digestion (restriction fragment length polymorphisms) or sequencing of the PCR products. Identification was based on sequence homology of the intergenic spacer region (IGS) between the ,- and ,-phycocyanin subunits (PC-IGS) with database records. We have found that the length and sequence of the PC-IGS is capable of predicting the genus accurately, but not the species. Toxigenicity was determined with oligonucleotide probes for key steps in the microcystin toxin synthesis pathway. We have shown that it is possible to easily and routinely obtain PCR amplification products and differentiate the strains in bloom samples. The methods can detect even minor components in bloom samples, which may not be apparent on microscopic examination. Genetic probes for microcystin toxigenicity are effective on environmental samples, eliminating the need for isolation and culture of the organisms. The use of a suite of tests described here will allow water managers to determine the presence and the type of cyanobacteria and their microcystin toxigenicity. © 2001 John Wiley & Sons, Inc. Environ Toxicol 16: 472,482, 2001 [source] Subtracted restriction fingerprinting , a new typing technique using magnetic capture of tagged restriction fragmentsFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2004Valeri Terletski Abstract Molecular typing of bacterial pathogens is an important issue in the epidemiological analysis of emerging infections in humans and animals. Numerous methods have been developed for and applied to a wide variety of bacteria of medical, veterinary and zoonotic importance. The present minireview provides a description of a new typing approach designated subtracted restriction fingerprinting (SRF), its use for typing of Salmonella isolates and a comparison with the most widely used typing techniques for these bacteria. SRF is based on double restriction endonuclease digestion of whole cell DNA, followed by a fill-in reaction with specifically tagged nucleotides and subtractive capture of selected restriction fragments. This results in a reduced number of fragments optimal for separation in standard agarose gels. [source] Genetic association of vitamin D receptor polymorphisms with primary biliary cirrhosis and autoimmune hepatitisHEPATOLOGY, Issue 1 2002Arndt Vogel Autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) are immune-mediated chronic inflammatory diseases of the liver of unknown etiology. Genetic factors appear to be involved in the pathogenesis of both diseases. 1,25-Dihydroxyvitamin D3 has been implicated as an immunomodulator, which acts through its own receptor (VDR). Polymorphisms of the VDR have been linked to a variety of autoimmune diseases. In this study VDR polymorphisms were analyzed in 123 patients with AIH, 74 patients with PBC, and 214 controls. VDR polymorphisms were assessed by BsmI, TaqI, ApaI, and Fok endonuclease digestion after specific polymerase chain reaction (PCR) amplification. We found a significant association between the BsmI polymorphisms in PBC patients in comparison with controls (,2 = 9.49, P = .009). Furthermore we detected a significant association of the Fok polymorphims in AIH patients in comparison to controls (,2 = 9.71, P = .008) indicating a genetic link of VDR polymorphisms to autoimmune liver diseases such as PBC and AIH in German patients. These findings contribute to the knowledge of the complex events determining immunologic tolerance in the liver. Further studies are needed to elucidate the mechanisms by which the vitamin D receptor contributes to the development of autoimmune diseases. [source] Gene polymorphisms of tissue plasminogen activator and plasminogen activator inhibitor-1 in Turkish patients with generalized aggressive periodontitisJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2007Gülnur Emingil Abstract Aim: Tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) have important roles in proteolytic events in periodontitis. The aim of this study was to investigate TPA and PAI-1 gene polymorphisms in relation to susceptibility to generalized aggressive periodontitis (G-AgP). Methods: Genomic DNA was obtained from peripheral blood of 90 G-AgP patients and 154 periodontally healthy subjects. 4G/5G polymorphism in the promoter region of the PAI-1 gene and Alu-repeat insertion/deletion (I/D) polymorphism in intron 8 of the TPA gene were genotyped by polymerase chain reaction and endonuclease digestion. Results: The genotype distributions of TPA and PAI-1 genes were similar between G-AgP and healthy subjects (p>0.05). The distribution of TPA genotypes in G-AgP patients was 33.4% D/D, 44.4% I/D, and 22.2% I/I and was 26.3% D/D, 40.4% I/D, and 33.3% I/I in healthy subjects. The D allele was 55.6% in G-AgP and 46.6% in healthy subjects. There was a significant difference among study groups in D allele frequencies (p=0.044). The PAI-1 genotype distribution in G-AgP was 29.1% 4G/4G, 43.0% 4G/5G, and 27.9% 5G/5G, while it was 35.7% 4G/4G, 43.8% 4G/5G, and 20.5% 5G/5G in healthy subjects. Conclusion: These data suggest that the D polymorphic allele of TPA gene polymorphism could be associated with susceptibility to G-AgP in Turkish subjects. [source] Bacteriophages induced from lysogenic root canal isolates of Enterococcus faecalisMOLECULAR ORAL MICROBIOLOGY, Issue 4 2009R. H. Stevens Introduction:, Bacterial viruses play crucial roles in the pathogenesis of many systemic diseases. They are known to inhabit the oral cavity, both as free virions and as prophages in lysogenic bacterial strains; however, there has been no report of bacteriophages in endodontic infections. In this study, we sought to detect, isolate, and describe temperate bacteriophages harbored by Enterococcus faecalis strains isolated from endodontic infections. Methods: Ten E. faecalis strains were isolated from root canals of teeth undergoing retreatment following unsuccessful endodontic therapy. Mitomycin C was used to induce any prophages present in the bacterial isolates. The induced phages were purified and examined using electron microscopy. The DNA extracted from one of the phage isolates was subjected to restriction endonuclease digestion and agarose electrophoresis analysis. Results:, Lysogeny was demonstrated in 4 of the 10 E. faecalis strains. Three of the lysogenic strains yielded phages exhibiting a Siphoviridae morphology, with long, non-contractile tails 130 nm in length, and spherical/icosahedral heads 41 nm in diameter. The virus induced from the fourth lysogenic E. faecalis strain had a contractile tail characteristic of Myoviridae. Restriction endonuclease analysis of NsiI and NdeI DNA fragments from one of the Siphoviridae phage isolates (phage ,Ef11) indicated a genome size of approximately 41 kbp. Conclusion:, This is the first report of lysogenic bacteria and their inducible viruses in infected root canals. [source] Sex determination in cattle based on simultaneous amplification of a new male-specific DNA sequence and an autosomal locus using the same primersMOLECULAR REPRODUCTION & DEVELOPMENT, Issue 1 2001Rosemarie Weikard Abstract A PCR-based method for sex determination of bovine DNA samples and embryo biopsies is presented. Using only one primer pair both the male-specific sequence FBNY (127 bp) and a sex-independent control PCR-fragment, the microsatellite marker FBN17 (136,140 bp) are generated in the same PCR reaction. Synteny mapping assigned the male-specific sequence to bovine chromosome Y (BTA Y), whereas FBN17 was mapped to bovine chromosome 2. Localisation of FBNY on BTA Y was confirmed by fluorescence in hybridisation of two BAC clones containing the male-specific sequence. There was no amplification of the male-specific target sequence FBNY in sheep, pig, goat, mice, man, and several wild species of the tribe Bovini. The bovine male-specific fragment was detected in dilutions containing as little as 10 pg genomic DNA and in blastomeres from embryo biopsies. The PCR assay presented here does require neither restriction endonuclease digestion of the PCR product nor additional nested PCR steps. Owing to the advantage of parallel amplification of the autosomal locus FBN17 no additional control fragment is necessary to detect PCR failure. The results of sex determination in embryo biopsies using FBNY were in agreement with the outcome from a reference assay used in commercial breeding programs. Mol. Reprod. Dev. 60: 13,19, 2001. © 2001 Wiley-Liss, Inc. [source] ORIGINAL ARTICLE: Association Study of Vascular Endothelial Growth Factor and Polymorphisms of its Gene with Ectopic PregnancyAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2010Julio Elito Jr Citation Elito J Jr, Daher S, Fernandes da Silva MO, Marconi NMH, Pendeloski KPT, Moron AF, Camano L. Association study of vascular endothelial growth factor and polymorphisms of its gene with ectopic pregnancy. Am J Reprod Immunol 2010; 63: 120,125 Problem, In ectopic pregnancy, increased levels of vascular endothelial growth factor are present. The aims of this study were to determine the association between ,634C/G, ,460T/C, and +936C/T vascular endothelial growth factor (VEGF) polymorphisms and ectopic pregnancy, and to determine whether serum levels of VEGF were affected by genetic factors. Method of study, This is a case,control study wherein 74 women with a history of ectopic pregnancy in a tertiary care center were compared to 134 post-menopausal controls with two pregnancies and no ectopic pregnancy for the genotyping of VEGF polymorphisms. For 35 patients with the diagnosis of ectopic pregnancy, serum concentrations of VEGF were obtained before the treatment. Genotyping of VEGF (,634C/G, ,460T/C, and +936C/T) polymorphisms was performed by PCR, followed by endonuclease digestion. ELISA was performed to evaluate the VEGF serum levels. Results, The ,634C/G, ,460T/C, and +936C/T VEGF polymorphisms were not associated with ectopic pregnancy (P = 0.170, P = 0.285, and P = 0.700, respectively). The serum levels of VEGF were not associated with the genotype of ,634C/G, ,460T/C, and +936C/T VEGF polymorphisms (P = 0.702; P = 0.347, and P = 0.256, respectively). Conclusion, There was no association between ectopic pregnancy and ,634C/G, ,460T/C, and +936C/T VEGF polymorphisms. There was no correlation between VEGF genotype and the expression of VEGF in blood samples. [source] Mannose-binding lectin gene polymorphism and resistance to therapy in women with recurrent vulvovaginal candidiasisBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 10 2008GGG Donders Precis, Women with recurrent vulvovaginal candidiasis (RVC) due to a polymorphism in codon 54 of the MBL2 gene respond better to fluconazole maintenance therapy than do women with other underlying causes. Objective, To explain differences in response rates to maintenance therapy with fluconazole in women suffering from RVC by evaluating associations with a polymorphism in the gene coding for mannose-binding lectin (MBL). Design, Follow-up study, neted case-control group. Setting, Women attending vulvoginitis clinic for RVC. Population, Women participating in a multicentric study in Belgium with a degressive dose of fluconazole for RVC (the ReCiDiF trial) were divided into good responders, intermediate responders and nonresponders according to the number of relapses they experienced during therapy. From 109 of these women with adequate follow-up data, vaginal lavage with 2 ml of saline were performed at the moment of a proven acute attack at inclusion in the study, before maintenance treatment was started. A buccal swab was obtained from 55 age-matched women without a history of Candida infections, serving as a control group. Methods, Extracted DNA from buccal or vaginal cells was tested for codon 54 MBL2 gene polymorphism by polymerase chain reaction and endonuclease digestion. Main outcome measures, Frequency of MBL2 condon 54 allele B in women with optimal or poor response to maintenance therapy in composition with controls. Results, Women (n = 109) suffering from RVC were more likely to carry the variant MBL2 codon 54 allele B than control women (20 versus 6.6%, OR 3.4 [95% CI 1.3,8.2], P = 0.01). B alleles were present in 25% of the 36 women not suffering from any recurrence during the maintenance therapy with decreasing doses of fluconazole (OR 4.9 [95% CI 1.9,12.5], P = 0.0007 versus controls), in 20% of the 43 women with sporadic recurrences (OR 3.6 [95% CI 1.4,9.2], P = 0.007 versus controls) and in 15% of the 30 women who had to interrupt the treatment regimen due to frequent relapses (P = 0.097 versus controls). Conclusions, The MBL2 codon 54 gene polymorphism is more frequent in Belgian women suffering from RVC than in controls. The presence of the B allele is associated with a superior response to fluconazole maintenance therapy as compared with RVC patients without this polymorphism. We conclude that RVC due to deficient MBL production is more easily helped with antifungal medication than is RVC due to some other mechanism. [source] High frequency of the 425A,G splice-site mutation and novel mutations of the COL7A1 gene in central Europe: significance for future mutation detection strategies in dystrophic epidermolysis bullosaBRITISH JOURNAL OF DERMATOLOGY, Issue 5 2005M. Csikós Summary Background, Mutations in the type VII collagen gene (COL7A1) are responsible for dominant and recessive forms of dystrophic epidermolysis bullosa (DEB). These mutations are usually specific for individual families; only a few cases of recurring mutations have been identified. Objectives, Forty-three unrelated Hungarian and German patients with different DEB phenotypes were screened for novel and recurrent COL7A1 mutations. Methods, All patients were classified based on clinical and genetic findings, skin immunofluorescent antigen mapping, and electron microscopic studies. Mutation analysis was performed by amplification of genomic DNA with polymerase chain reaction using COL7A1 -specific primers, heteroduplex analysis, and direct nucleotide sequencing. Restriction endonuclease digestion was used for family screening and mutation verification. Results, In this group of patients, the splice-site mutation 425A,G was observed frequently, in 11 of 86 alleles (12·8%), once in homozygous form and in nine cases in heterozygous form. One of 100 control alleles from clinically unaffected individuals also carried the mutation. We also identified three novel mutations: the 976-3C,A splice-site mutation, and the 4929delT and 8441-15del20 deletions. Conclusions, High recurrence of the splice-site mutation 425A,G in central European patients with DEB should be taken into account when designing COL7A1 mutation detection strategies. Reporting of three novel COL7A1 mutations in this study further emphasizes the molecular heterogeneity of DEB and provides more information for studies on genotype,phenotype correlations in different DEB subtypes. [source] |