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1.
Int J Immunogenet ; 41(6): 493-8, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25256363

ABSTRACT

Several lines of evidence suggest that certain subtypes of obsessive-compulsive and tic disorders might be paediatric manifestations of post-streptococcal autoimmunity caused by cross-reactive autoantibodies. As tumor necrosis factor (TNF) is known to play a seminal role in coordinating the humoral immune response, TNF gene polymorphisms have been proposed as genetic risk factors both in obsessive-compulsive disorder (OCD) and Tourette syndrome (TS). The aim of this study was to investigate two TNF promoter polymorphisms (-238 A/G: rs361525 and -308 A/G: rs1800629) on the genetic susceptibility to OCD and TS in a child psychiatric sample (102 patients with OCD and 117 patients with TS). In the case-control set-up, the genotype and allele frequencies were compared to a control group from the general population (n = 405). As a control child psychiatric sample, 194 children with attention-deficit hyperactivity disorder were also genotyped. Our results revealed that the TNF -308 G-allele was more frequent in children with TS compared to controls (90.2% vs 84.8%, P = 0.037). For confirmation of this genetic association, a family-based analysis, the transmission disequilibrium test was used, which showed preferential transmission of the G-allele to patients with TS (nominal P-value 0.011). Moreover, this allele was also transmitted more frequently to children with tic symptoms (nominal P-value 0.039). No association was found between OCD or obsessive-compulsive symptoms and the studied TNF polymorphisms. Based on these findings, the TNF -308 G-allele can be associated with Tourette syndrome, highlighting the potential pathophysiological role of TNF dysregulation.


Subject(s)
Genetic Association Studies , Genetic Predisposition to Disease , Polymorphism, Genetic , Promoter Regions, Genetic , Tourette Syndrome/genetics , Tumor Necrosis Factor-alpha/genetics , Case-Control Studies , Child , Female , Gene Frequency/genetics , Humans , Male
2.
Genes Brain Behav ; 11(4): 444-51, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22435649

ABSTRACT

The etiology and pathophysiology of Tourette Syndrome (TS) remain poorly understood. Multiple lines of evidence suggest that a complex genetic background and the cortico-striato-thalamo-cortical circuit are involved. The role of Lhx6 and Lhx8 in the development of the striatal interneurons, prompted us to investigate them as novel candidate genes for TS. We performed a comparative study of the expression of Lhx6 and Lhx8 and investigated genetic association with TS using two samples of trios (TSGeneSEE and German sample - 222 families). We show that Lhx6 and Lhx8 expression in the forebrain is evolutionarily conserved, underlining their possible importance in TS-related pathophysiological pathways. Our tagging-single nucleotide polymorphism (tSNP)-based association analysis was negative for association with LHX8. However, we found positive association with LHX6 in the TSGeneSEE sample (corrected P-value = 0.006 for three-site haplotype around SNP rs3808901) but no association in the sample of German families. Interestingly, the SNP allele that was identified to be significantly associated in the TSGeneSEE dataset, showed an opposite trend of transmission in the German dataset. Our analysis of the correlation of the LHX6 region with individual ancestry within Europe, revealed the fact that this particular SNP demonstrates a high degree of population differentiation and is correlated with the North to South axis of European genetic variation. Our results indicate that further study of the LHX6 gene in relation to the TS phenotype is warranted and suggest the intriguing hypothesis that different genetic factors may contribute to the etiology of TS in different populations, even within Europe.


Subject(s)
Basal Ganglia/metabolism , LIM-Homeodomain Proteins/genetics , Nerve Tissue Proteins/genetics , Polymorphism, Single Nucleotide , Tourette Syndrome/genetics , Transcription Factors/genetics , Adolescent , Adult , Alleles , Animals , Female , Genetic Association Studies , Haplotypes , Humans , Interneurons/metabolism , LIM-Homeodomain Proteins/metabolism , Male , Mice , Nerve Tissue Proteins/metabolism , Rats , Tourette Syndrome/metabolism , Transcription Factors/metabolism , White People/genetics
4.
Mol Psychiatry ; 15(2): 216-25, 2010 Feb.
Article in English | MEDLINE | ID: mdl-18574484

ABSTRACT

Genetic variation at the catechol-O-methyltransferase (COMT) gene has been significantly associated with risk for various neuropsychiatric conditions such as schizophrenia, panic disorder, bipolar disorders, anorexia nervosa and others. It has also been associated with nicotine dependence, sensitivity to pain and cognitive dysfunctions especially in schizophrenia. The non-synonymous single nucleotide polymorphism (SNP) in exon 4--Val108/158Met--is the most studied SNP at COMT and is the basis for most associations. It is not, however, the only variation in the gene; several haplotypes exist across the gene. Some studies indicate that the haplotypic combinations of alleles at the Val108/158Met SNP with those in the promoter region and in the 3'-untranslated region are responsible for the associations with disorders and not the non-synonymous SNP by itself. We have now studied DNA samples from 45 populations for 63 SNPs in a region of 172 kb across the region of 22q11.2 encompassing the COMT gene. We focused on 28 SNPs spanning the COMT-coding region and immediately flanking DNA, and found that the haplotypes are from diverse evolutionary lineages that could harbor as yet undetected variants with functional consequences. Future association studies should be based on SNPs that define the common haplotypes in the population(s) being studied.


Subject(s)
Catechol O-Methyltransferase/genetics , Genetic Predisposition to Disease , Linkage Disequilibrium , Polymorphism, Single Nucleotide/genetics , Population Groups/genetics , Animals , Databases, Genetic , Gene Frequency , Genotype , Humans
5.
Int J Syst Bacteriol ; 46(1): 280-97, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8573508

ABSTRACT

During previous cooperative numerical taxonomic studies of slowly growing mycobacteria, the International Working Group on Mycobacterial Taxonomy described a number of strains whose taxonomic status was ambiguous. A new study of DNA, RNA, and proteins from 66 of these organisms was performed to correlate their properties with phenotypic clustering behavior; the results of this study permitted 51 of the strains studied to be assigned to known species. The methods used to characterize the semantides included nucleotide sequencing and assessment of levels of semantide relatedness by affinity binding techniques, including whole DNA-DNA hybridization, probe hybridization, and antibody binding. There was good overall agreement between the phenotypic and chemotaxonomic clusters and the groups of organisms identified by semantide analyses. Our results supported the conclusion that we should continue to rely on polyphasic taxonomy to provide satisfactory systematic resolution of members of the genus Mycobacterium. We identified no single 16S rRNA interstrain nucleotide sequence difference value that unequivocally defined species boundaries. DNA-DNA hybridization remains the gold standard, but common resources are needed to permit DNA-DNA hybridization analyses to be made available to laboratories that are not prepared to use this technology. One of the large novel clusters which we studied corresponds to the recently described species Mycobacterium interjectum, a pathogen that resembles the nonpathogen Mycobacterium gordonae phenotypically. We also identified strains that appear to represent ribovars of Mycobacterium intracellulare which do not react with the commercial diagnostic probes that are currently used for identification of this species. Other branches or clusters consisted of too few strains to permit a decision about their taxonomic status to be made.


Subject(s)
Mycobacterium/classification , Bacterial Proteins/genetics , DNA, Bacterial/genetics , Molecular Sequence Data , Mycobacterium/chemistry , Mycobacterium/genetics , Phenotype , Phylogeny , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics
6.
Int J Syst Bacteriol ; 43(2): 352-7, 1993 Apr.
Article in English | MEDLINE | ID: mdl-7684243

ABSTRACT

Strains of a new type of slowly growing scotochromogenic, rose-pink-pigmented mycobacterium were isolated repeatedly from sphagnum vegetation, true moss, and soil in Ireland. These strains grew at 22, 31, and 37 degrees C but not at 45 degrees C and possessed acid phosphatase and arylsulfatase activities. They reduced nitrate, tolerated 0.1% NaNO2, did not split amides, and were resistant to most of the antituberculous drugs tested, except ethambutol. They did not form acid from glucose and mannose. Their internal phenetic similarity was 97.08% +/- 2.07%. The whole mycolate pattern confirmed the homogeneity of the taxa sharing similar mycolate types with several other mycobacterial species. However, on the basis of the nature of the major pyrolysis esters, the taxon appeared unique. The phylogenetic analysis based on evolutionary distance values revealed that the strains belong to a new species of slowly growing mycobacteria. The DNA-DNA hybridization values confirmed that these strains differ significantly from Mycobacterium nonchromogenicum, M. terrae, M. triviale, and M. thermoresistibile. The strains produced a unique rose-pink pigment and were nonpathogenic for mice, guinea pigs, and rabbits, but they provoked a nonspecific hypersensitivity reaction to bovine tuberculin in guinea pigs and cattle. Hence, they are considered a member of a new species of nonpathogenic slowly growing mycobacteria, for which the name Mycobacterium hiberniae is proposed. Strain Hi 11 is the type strain, a culture of which has been deposited in the American Type Culture Collection as strain ATCC 49874.


Subject(s)
Mycobacterium/classification , Bacterial Typing Techniques , Biological Evolution , Classification , Cluster Analysis , DNA, Bacterial/genetics , Ireland , Molecular Sequence Data , Mycobacterium/growth & development , Mycobacterium/isolation & purification , Mycolic Acids/analysis , Nucleic Acid Hybridization , Phylogeny , Plants/microbiology , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Sequence Homology, Nucleic Acid
7.
Infect Immun ; 58(3): 808-15, 1990 Mar.
Article in English | MEDLINE | ID: mdl-2106495

ABSTRACT

Pyocyanine, a pigment produced by Pseudomonas aeruginosa, has dual dose-dependent stimulatory as well as inhibitory effects on immune responses in vitro as measured by DNA synthesis of human T and B lymphocytes, interleukin-2 (IL-2) production by human T lymphocytes, immunoglobulin production by human B lymphocytes, and monokine production by human monocytes. In general, stimulatory activity was found at low concentrations of pyocyanine, whereas high concentrations of the pigment resulted in an inhibition of responses. At a pyocyanine concentration of 0.1 micrograms/ml or less the proliferation of T and B lymphocytes was enhanced, but at 0.5 micrograms/ml it was suppressed. IL-2 production by T lymphocytes was enhanced at concentrations up to 0.5 micrograms/ml but totally inhibited at 1.0 micrograms/ml. The differentiation of B lymphocytes to become immunoglobulin-producing cells was also enhanced in the presence of low doses of pyocyanine, whereas secretion of immunoglobulin by B lymphocytes was suppressed at all concentrations of pyocyanine. In contrast to the dual effects of pyocyanine on lymphocyte response, lipopolysaccharide-induced IL-1 and tumor necrosis factor release by monocytes was markedly enhanced by low as well as high concentrations of pyocyanine. From these results we conclude that this property of pyocyanine may lead to suppression of specific defense mechanisms and enhance harmful inflammatory reactions of the host during infection with Pseudomonas aeruginosa.


Subject(s)
B-Lymphocytes/drug effects , Monocytes/drug effects , Phenazines/pharmacology , Pseudomonas aeruginosa/pathogenicity , Pyocyanine/pharmacology , T-Lymphocytes/drug effects , B-Lymphocytes/immunology , DNA/biosynthesis , Humans , Interleukin-1/biosynthesis , Interleukin-2/biosynthesis , Lipopolysaccharides/pharmacology , Lymphocyte Activation/drug effects , Monocytes/immunology , Phytohemagglutinins/pharmacology , Pokeweed Mitogens/pharmacology , T-Lymphocytes/immunology , Tumor Necrosis Factor-alpha/biosynthesis
8.
Int J Tissue React ; 12(1): 47-52, 1990.
Article in English | MEDLINE | ID: mdl-2166718

ABSTRACT

Two different results have been published in regard to the superoxide-stimulating activity of lipopolysaccharide or Lipid A in neutrophils: first, a direct stimulation after a lag time of about 30-60 sec and second, the inactivity of Lipid A if applied alone, being able only to "prime" the cells for a second challenge during a longer incubation period. In order to achieve clarity regarding these two different opinions, we asked the questions whether: (a) Lipid A is able to stimulate PMN directly, i.e. without a preincubation and a second stimulus; (b) fMLP and Lipid A show a synergistic effect; (c) a preincubation ("priming") of the PMN with Lipid A really increases the superoxide output after a second challenge. We observed (a) a direct stimulation of the chemiluminescence with Lipid A without an additional second challenge, accompanied by a seemingly unimodal kinetics of the superoxide output, i.e. mainly the second phase of the usually bimodal kinetics has been stimulated. As for question (b), a clearly detectable synergism between Lipid A and fMLP could be measured. Regarding question (c), a preincubation ("priming") with Lipid A was of no beneficial effect; the chemiluminescence count could be equally well increased without a "priming" compound.


Subject(s)
Lipid A/pharmacology , Neutrophils/drug effects , Superoxides/metabolism , Drug Synergism , Humans , In Vitro Techniques , Kinetics , Luminescent Measurements , N-Formylmethionine Leucyl-Phenylalanine/pharmacology , Neutrophils/metabolism
9.
Agents Actions ; 24(3-4): 261-5, 1988 Jul.
Article in English | MEDLINE | ID: mdl-3177091

ABSTRACT

As determined by luciferase-luciferin, we recently found that the H2-blocker CIM considerably increased the ATP release from fMLP-stimulated PMN. This observation correlates well with our previous [1] regarding the enhancement of superoxide output (chemiluminescence) in in human neutrophils. by CIM plus fMLP. In order to compare the ATP release from PMN of different donors, a standard procedure has been developed consisting of the determination of the ATP present initially in the cell suspension (without stimulation), ATP release after stimulation with fMLP, and ATP release in the presence of CIM plus fMLP. The whole ATP content per neutrophil was determined after ultrasonication of the cells as well. The mean value of the initially present ATP was 0.45 x 10(-17) mol/cell in the suspension. Stimulation with fMLP plus CIM yielded within 5-10 minutes considerably higher ATP amounts than fMLP alone. The corresponding and statistically significantly different mean values were 2.46 x 10(-17) mol/PMN (s.d. = 1.047) and 1.38 x 10(-17) mol/PMN (s.d. = 0.55), respectively. The whole ATP per neutrophil was found to be 1.22 x 10(-15) mol (mean; s.d. = 0.60) and thus, the stimulation with CIM plus fMLP released about 2.0 per cent, with fMLP alone about 1.0 per cent of the whole ATP. CIM without fMLP did not enhanced the ATP release during the reaction time applied. On the other hand, fMLP-stimulated, lucigenin-amplified chemiluminescence determinations were carried out in the presence of CIM as well; contrarily to our previous method, CIM was dissolved in PBS without DMSO, because DMSO inhibited the chemiluminescence slightly.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Adenosine Triphosphate/metabolism , Chemotactic Factors/physiology , Cimetidine/pharmacology , Luminescent Measurements , Neutrophils/drug effects , Cells, Cultured , Firefly Luciferin , Humans , Luciferases , Neutrophils/metabolism
10.
Agents Actions ; 20(3-4): 324-6, 1987 Apr.
Article in English | MEDLINE | ID: mdl-3037867

ABSTRACT

We investigated the influence of CIM and HIS on the SUP and CH in the SUP generating cell-free xanthine oxidase system and in human neutrophils. As measured by CCR or CH, we found that HIS inhibited SUP output in both systems. The HIS concentration required for a measurable inhibition was somewhat higher in the xanthine oxidase system than in neutrophils. CIM increased CH in neutrophils significantly. A similar effect of CIM was not observed in the xanthine oxidase system. CIM antagonized in neutrophils the effect of HIS. However, a five or ten times higher molar concentration of CIM than of HIS was necessary to produce this effect. The antagonistic effect of CIM was not found in the xanthine oxidase system within the concentrations applied. In addition to an interaction of HIS with neutrophils on the cellular level, we suggest a superoxidase scavenging effect caused by HIS. At the present no suggestions can be made regarding the observed SUP output stimulating activity of CIM.


Subject(s)
Cimetidine/pharmacology , Histamine/pharmacology , Neutrophils/drug effects , Superoxides/metabolism , Cell-Free System , Humans , Neutrophils/metabolism , Xanthine Oxidase/metabolism
11.
Agents Actions ; 18(1-2): 34-7, 1986 Apr.
Article in English | MEDLINE | ID: mdl-3728214

ABSTRACT

Mycobacterium smegmatis SN 46, isolated from a fatal human oesophagus infection, is able to degrade HIS by imidazole ring splitting. In this respect, SN 46 is unique under the bacteria strains tested. Some other mycobacteria (M. diernhoferi, M. fortuitum, M. chelonei etc.) oxidize HIS to IMET and IMAC without further change. Cell-free extracts of SN 46 transform HIS to IMET and IMAC, while ring splitting enzymes are not detectable. IMAC and IMET were identified by combined gas-liquid chromatography and mass-spectrometry. At present, the possibility of HIS degradation by SN 46 via imidazolyl acetaldehyde (according to the pathway in vertebrates) can not be excluded.


Subject(s)
Histamine/analogs & derivatives , Histamine/metabolism , Imidazoles , Mycobacterium/metabolism , Gas Chromatography-Mass Spectrometry , Histamine/analysis
13.
Zentralbl Bakteriol Orig A ; 244(2-3): 302-8, 1979 Jul.
Article in German | MEDLINE | ID: mdl-506551

ABSTRACT

Nicotin- and the so-called pyrazinamidase (in the following: "pyrazinamidase") have been found in strains of four mycobacteria species, M. fortuitum, M. gastri, M. bovis and M. microti. These findings are in contradiction to those summarized in Bergey's Manual of Determinative Bacteriology (1974). The reason for the discrepancies is that the original method (Bönicke, 1961) for amidase determination has not taken the following aspects into consideration: a) The inducibility of the nicotin- and "pyrazinamidase" (example: M. fortuitum); b) The temperature sensitivity of these enzymes (M. gastri); c) The light sensitivity of nicotinamidase (in photochromogenic M. gastri strains); d) The optimal substrate concentration which must be at least 4 mM instead of 0,8 mm. The following consequences can be drawn for the taxonomy and biochemistry of the tested organisms: e) The species status of M. gastri should be annuled. The main difference between M. gastri and M. kansasii consists only of the non-agglutinability of M. gastri by anti-M. kansasii serum. "Pyrazinamidase" and also nitrate reductase (Tarnok et al., in press) are positive in strains of both species; f) M. bovis possesses nicotin- and "pyrazinamidase" as M. tuberculosis too. Thus, these two species are more closely related than suggested earlier; g) Till now, no Mycobacterium has been found showing nicotinamidase without "pyrazinamidase" activity (or vice versa). It seems to be very probable that nicotinamidase, an enzyme of low substrate specificity, is able to hydrolyze several compounds with a nicotinamide-like structure such as pyrazinamide. Thus, we suggest the annulment of the term pyrazinamidase or the employment of quotation marks ("pyrazinamidase") to show the fictitious value of this designation.


Subject(s)
Amidohydrolases/metabolism , Mycobacterium/enzymology , Nicotinamidase/metabolism , Pyrazinamide
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