MTHFR gene polymorphism, homocysteine and cardiovascular disease.

AbstractHomocysteine is an emerging new risk factor for cardiovascular disease. It is a thiol compound derived from methionine and involved in two main metabolic pathways: the cycle of activated methyl groups, requiring folate and vitamin B12 as cofactors, and the transsulfuration pathway to cystathionine and cysteine requiring vitamin B6 as cofactor. The homocysteine metabolism represents an interesting model of gene-environment interaction. Elevations in homocysteine may be caused by genetic defects in enzymes involved in its metabolism or by deficiencies in cofactor levels. A common polymorphism in the gene coding for the 5, 10-methylene tetrahydrofolate reductase (MTHFR) (C677T, Ala → Val) is associated with a decreased activity of the enzyme due to thermolability. In case of homozygosity for the Val allele, a relative deficiency in the remethylation process of homocysteine into methionine leads to a mild-to-moderate hyperhomocysteinemia, a condition recognized as an independent risk factor for atherosclerosis. The genetic influence of the MTHFR polymorphism on homocysteine levels is attenuated in females in premenopausal age and is not significant in subjects who exhibit serum levels of folate and/or vitamin B12 above the 50thpercentile of distribution in the general population. The prevalence of the Val/Val genotype varies among different ethnic groups. It is very low in African populations, whereas in Europe and North America it ranges between 5% and 15%. In Italy an even higher prevalence has been reported in some regions. The question whether the MTHFR polymorphism might beper sean independent contributor to cardiovascular risk is debated. The interaction between this or other genetic factors and environmental/nutritional conditions (i.e. intake of vitamins such as folate) is a key determinant for homocysteine concentrations in healthy conditions as well as in some disease (i.e. in renal disorders). Another example of gene/environment interaction in the field of atherosclerosis is given by the apolipoprotein E polymorphism and its influence in response to diet. The presence of a high prevalence of risk-related allelic variants of such candidate genes within a certain population could serve to locally reinforce the recommendations concerning nutrient intake

Daily effect of recovery on exhaustion: A cross-level interaction effect of workaholism

Workaholics generally allocate an excessive amount of time and energy to their work at the expense of having time for recovery from work. Nevertheless, a complete recovery is an essential prerequisite for well-being. This study examines the moderating role of workaholism in the relationship between daily recovery and daily exhaustion. Data were collected among 95 participants who completed a general questionnaire and a diary booklet for five consecutive working days. Multilevel analysis results confirmed a cross-level interaction effect of workaholism, showing that the negative relationship between recovery and exhaustion at the daily level is weaker for those with a high (versus low) level of workaholism. These insights suggest the promotion of interventions aimed at addressing workaholism among workers, and the design of projects able to stimulate recovery from work, particularly for workaholics

One-step transversal palatal distraction and maxillary repositioning: technical considerations, advantages, and long-term stability.

One-step transversal palatal distraction and maxillary repositioning: technical considerations, advantages, and long-term stability. Cortese A, Savastano M, Savastano G, Claudio PP. Source Department of Oral and Maxillofacial Sciences, University of Naples Federico II, Naples, Italy. Abstract BACKGROUND: Transversal maxillary hypoplasia in adolescence is a frequently seen pathology, which can be treated with a combination of surgery and orthodontic treatment to widen the maxilla in skeletally matured patients.We evaluated the advantages of a new surgical technique: Le Fort I distraction osteogenesis using a bone-borne device. Because relapse is one of the main problems in surgical maxillary expansion, long-term stability of this new technique was evaluated. METHODS: Data from 4 adult patients with maxillary restriction, class III malocclusion, or maxillary malposition were collected preoperatively, 4 months after distraction, and 5 years after distraction. Measurements were recorded on dental models to detect palatal expansion at dental level; cephalograms by lateral and posteroanterior plane were analyzed to detect maxillary movements. RESULTS: Maxillary measurements were substantially stable 5 years after distractions. Only minor dental movements occurred at the dental analysis after 5 years related to a lack of orthodontic contention without any compromise of the dental result (no crossbite relapse and class I stability). CONCLUSIONS: Le Fort I with down-fracture for expansion and repositioning by bone-borne distractor device cannot be used to simultaneously widen, advance, and vertically reposition the maxilla without causing healing problems, particularly using a rigid distraction device. Long-term stability can be achieved; however, further studies with a larger number of patients will be necessary for better evaluation. PMID: 21959418 [PubMed - indexed for MEDLINE