			Home About us Contact

Methyl Transferase (methyl + transferase)

Distribution by Scientific Domains

Medical Sciences	44%
Chemistry	44%

Selected Abstracts

Study: The Lack of Significant Association of the Catechol- O -Methyl Transferase (COMT) Gene Polymorphism in Violent Offenders with Mental Retardation

JOURNAL OF FORENSIC SCIENCES, Issue 1 2010
Aysun Baransel Isir M.D.
Abstract:, Little is known about criminality of cognitively impaired people and also there have been no reports on the relationship between catechol- O -methyl transferase (COMT) and committed Mental Retardation (MR) subjects. In the present study, the association between committed (violent offences) MR subjects and genetic variants of COMT were investigated by using polymerase chain reaction and based restriction fragment length polymorphism methods. During 6 years of follow-up, 36 violent offenders with mild MR were investigated. Thirty-six control volunteers were included in the study as a control group. H/L polymorphism of the COMT gene was investigated in these two groups. In conclusion, the COMT gene genotype distribution and allele frequency is not significantly different between the two groups (p > 0.05). This result suggests that the H/L polymorphism of the COMT gene does not show an association with the potential of "commits-violent offense" of Turkish subjects with mental retardation, compared with control group. [source]

Detecting methylation patterns of p16, MGMT, DAPK and E-cadherin genes in multiple myeloma patients

INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 2 2010
O. OZALP YUREGIR
Summary Multiple myeloma (MM) is a B-cell neoplasia characterized by the clonal proliferation of plasma cells. Besides known genetic abnormalities, epigenetic changes are also known to effect MM pathogenesis. DNA methylation is an epigenetic mechanism that silences genes by adding methyl groups to cytosine-guanine dinucleotides at the promoter regions. In this study, the methylation status of four genes; p16, O6-methyl guanine DNA methyl transferase (MGMT), death-associated protein kinase (DAPK) and E-cadherin (ECAD); at the time of diagnosis was investigated using methylation-specific polymerase chain reaction (MS-PCR). In the 20 cases studied; methylation of the promoter regions of p16, MGMT, DAPK and ECAD genes was detected in 10%, 40%, 10% and 45% of the cases, respectively. In 65% (13/20) of cases, at least one of the genes studied had promoter methylation; while 35% of cases (7/20) had methylated promoters of more than one gene. There was a significant correlation between promoter hypermethylation of MGMT and the presence of extramedullary involvement; but for the other genes no correlation was found regarding disease properties like age, disease stage, clinical course and the presence of lytic bone lesions. Determining the methylation profiles of genes in MM, could lead to a new understanding of the disease pathogenesis and guide the assessment of treatment options. [source]

Study: The Lack of Significant Association of the Catechol- O -Methyl Transferase (COMT) Gene Polymorphism in Violent Offenders with Mental Retardation

Sterol Composition of Pneumocystis jirovecii with Blocked 14,-Demethylase Activity

THE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 6 2004
JOSÉ-LUIS GINER
ABSTRACT Several drugs that interact with membrane sterols or inhibit their syntheses are effective in clearing a number of fungal infections. The AIDS-associated lung infection caused by Pneumocystis jirovecii is not cleared by many of these therapies. Pneumocystis normally synthesizes distinct C28 and C29 24-alkylsterols, but ergosterol, the major fungal sterol, is not among them. Two distinct sterol compositional phenotypes were previously observed in P. jirovecii. One was characterized by ,7 C28 and C29 24-alkylsterols with only low proportions of higher molecular mass components. In contrast, the other type was dominated by high C31 and C32 24-alkylsterols, especially pneumocysterol. In the present study, 28 molecular species were elucidated by nuclear magnetic resonance analysis of a human lung specimen containing P. jirovecii representing the latter sterol profile phenotype. Fifteen of the 28 had the methyl group at C-14 of the sterol nucleus and these represented 96% of the total sterol mass in the specimen (excluding cholesterol). These results strongly suggest that sterol 14,-demethylase was blocked in these organisms. Twenty-four of the 28 were 24-alkylsterols, indicating that methylation of the C-24 position of the sterol side chain by S-adenosyl-L-methionine:sterol C-24 methyl transferase was fully functional. [source]

The putative-farnesoic acid O -methyl transferase (FAMeT) gene of Ceratitis capitata: characterization and pre-imaginal life expression

ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 2 2010
Laura Vannini
Abstract Farnesoic acid O -methyl transferase (FAMeT) is the enzyme involved in the penultimate step of insect juvenile hormone (JH) biosynthesis and is thus a key regulator in insect development and reproduction. We report the characterization of the putative- FAMeT in the medfly or Mediterranean fruit fly, Ceratitis capitata. This gene was identified by suppressive subtractive hybridization and completely sequenced by the screening of a medfly cDNA library. The obtained sequence was analyzed for conserved protein domain identification and its expression profile was evaluated by quantitative Real-Time PCR in medfly pre-imaginal life. The tissue expression of the isolated gene was verified by in situ hybridization on third instar larvae sections. The characterization of the isolated gene pointed out several typical features of methyl transferase genes. The pre-imaginal putative- FAMeT expression levels were consistent with JH titer change in Diptera. As recognized in some crustaceans, this gene seems to be widely expressed in the medfly as well. Ceratitis capitata is one of the most relevant agricultural pests against which insecticides and the sterile insect technique (SIT) are extensively used in spite of the well-known limitations of these approaches. Although results are not conclusive for the physiological role of the isolated gene, they suggest the characterization of a new gene in the Mediterranean fruit fly potentially involved in JH biosynthesis and may, therefore, have implications for pest control. © 2010 Wiley Periodicals, Inc. [source]

Schizophrenia: genetics, prevention and rehabilitation

ACTA NEUROPSYCHIATRICA, Issue 3 2009
Paolo Olgiati
Objective:, Genetic factors are largely implicated in predisposing to schizophrenia. Environmental factors contribute to the onset of the disorder in individuals at increased genetic risk. Cognitive deficits have emerged as endophenotypes and potential therapeutic targets for schizophrenia because of their association with functional outcome. The aims of this review were to analyse the joint effect of genetic and environmental (G×E) factors on liability to schizophrenia and to investigate relationships between genes and cognitive endophenotypes focusing on practical applications for prevention and rehabilitation. Methods:, Medline search of relevant studies published between 1990 and 2008. Results:, In schizophrenia, examples of G×E interaction include the catechol- O -methyl transferase (COMT) (Val158Met) polymorphism, which was found to moderate the onset of psychotic manifestations in response to stress and to increase the risk for psychosis related to cannabis use, and neurodevelopmental genes such as AKT1 (serine-threonine kinase), brain-derived neurotrophic factor (BDNF), DTNBP1 (dysbindin) and GRM3 (metabotropic glutamate receptor 3), which were associated with development of schizophrenia in adulthood after exposure to perinatal obstetric complications. Neurocognitive deficits are recognised as core features of schizophrenia that facilitate the onset of the disorder and have a great impact on functional outcome. Neurocognitive deficits are also endophenotypes that have been linked to a variety of genes [COMT, neuregulin (NRG1), BDNF, Disrupted-In-Schizophrenia 1 (DISC1) and dysbindin] conferring susceptibility to schizophrenia. Recently, it has emerged that cognitive improvement during rehabilitation therapy was under control of COMT (Val158Met) polymorphism. Conclusion:, This review could indicate a pivotal role of psychiatric genetics in prevention and rehabilitation of schizophrenic psychoses. [source]

Management of severe adult atopic dermatitis

CLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 4 2002
Nicholas Reynolds
In common with many units, we run a specialist atopic eczema clinic that receives both secondary and tertiary referrals. Investigation into possible provoking factors includes RAST testing and patch testing where appropriate. The mainstay of treatment for moderate to severe atopic eczema remains topical steroids and emollients. Our specialist nurses play a key role in education and in particular demonstrating topical treatments , including bandaging. It is surprising that many patients have not previously been shown how to apply the treatments prescribed. Nevertheless, despite optimizing topical treatment protocols, a proportion of patients require hospital admission or second-line therapy. Our recent double-blind, randomized, controlled trial of narrow-band UVII vs. UVA (as used in PUVA) vs. placebo has confirmed that narrow-band WB phototherapy is an effective adjunctive treatment in moderate to severe atopic eczema. This trial also highlighted the value of recording disease activity (e.g. SASSAD) in individual patients following a change of therapy. UVA1 may be useful for acute severe atopic eczema but this UV source is only available in limited centres within the UK. Selected resistant patients or patients with acute flares are considered for short-term cyclosporin therapy. Azathioprine is widely used by consultant dermatologists in the UK as a second-line agent , despite the lack of evidence of efficacy. We are currently conducting a randomized placebo-controlled trial to address this issue. The importance of checking thiopurine methyl transferase (TPMT) prior to initiating azathioprine therapy has been emphasized. Our pilot data, with a dosage regime based on the TPMT result, suggest that patients may achieve a longer-term remission after a relatively short course. Mycophenolate mofetil has been reported to be effective in an open trial and methotrexate is also used but there is a lack of published evidence. The advent of topical tacrolimus and ascomycins, which have been shown to be effective in controlled trials, appear to be a promising development in the management of patients with moderate to severe atopic eczema and may lead to reduction in the use of systemic agents. [source]

Systemic immunosuppressant therapy in childhood

CLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 4 2002
David Atherton
The indications for systemic immunosuppressant therapy are much the same in children as in adults. Perhaps the most important difference is the need in a child to consider more carefully the patient's likely future therapy requirements. This need reflects a justifiable anxiety concerning the longer-term toxicity associated with some of these drugs. It is obvious that special attention should be paid to the dosage regimens that are appropriate in children. However, otherwise the principles of treatment are essentially the same as in adults. This talk will focus on the use of azathioprine in atopic eczema, methotrexate in psoriasis and linear morphoea, and intravenous methylprednisolone in severe muco-cutancous erythema multiforme and toxic epidermal necrolysis. The value of azathioprine as a treatment for severe childhood eczema was greatly increased by the elucidation of the metabolic pathways for this drug, and by the development of an assay for thiopurine methyl transferase to allow detection of those at greatest risk of myelosuppression. We now treat children with normal TPMT levels with 3 mg/kg per day with gratifying therapeutic response and limited requirement for monitoring of blood counts and liver function. More recently we have successfully treated TPMTHL heterozygotes with doses of around 1.5 mg/kg per day. We now consider azathioprine as superior to cyclosporin as a systemic therapy for atopic eczema. The value of methotrexate in adults with plaque psoriasis and generalized pustular psoriasis is well established. It is equally useful in children with these disorders, and the most appropriate dosage appears to be in the region of 0.3,0.4 mg/kg as a single weekly dose. Children generally tolerate oral therapy well. Methotrexate also appears helpful in arresting the progression of linear morphoea, both in the case of coup de sabre lesions and progressive hemi-facial atrophy, and in limb lesions that are interfering with joint mobility or are causing profound lipoatrophy. Intravenous methylprednisolone appears to be of value in several acute dermatoses in childhood, but is most commonly used at Great Ormond Street Hospital in the hope of arresting progression of severe muco-cutaneous erythema multiforme and toxic epidermal necrolysis. Various dose regimens are used in children, but in our unit we use a dose of 20,30 mg/kg per day, up to a maximum of 500 mg, for 3 successive days. Each dose is given over period of 2 h with frequent monitoring of vital signs, particularly blood pressure. [source]