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1.
Lasers Med Sci ; 39(1): 147, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822930

RESUMO

Photobiomodulation (PBM) holds promise as a therapy modality, but its applicability is hindered by the lack of a quantitative model to predict the optimal dose for all forms of PBM. This study investigated the optimal PBM parameters for 532 nm green laser irradiation on SHSY5Y neuroblastoma cells, a commonly used in vitro model for neurodegenerative disease studies. A two-tailed, two sample t-test with equal variance was used to obtain the p-values and statistical significance. There are 3 sets of parameters showing significant ( p < 0 . 01 ) positive percentage biostimulation. 160 m W , 15 m i n produce a percentage biostimulation of ( 9 ± 10 ) % ; 180 m W , 5 m i n produce a percentage biostimulation of ( 19 ± 7 ) % ; and ( 200 m W , 5 m i n ) produce a percentage biostimulation of ( 9 ± 2 ) % . The highest significant ( p < 0 . 01 ) percentage bioinhibition observed is for 220 m W , 15 m i n (dose: 1008 J / c m 2 ) producing a bioinhibition of ( 54 ± 1 ) % . After identifying several parameters that produce noticeable photobiological effects (biostimulation and bioinhibition), this study compared the reaction of undifferentiated and differentiated SHSY5Y cells to laser irradiation and found that undifferentiated SHSY5Y cells shows greater photobiological effect from 532 nm laser irradiation ( p < 0 . 01 ) . This study demonstrated the differentiation-dependant photobiological effect of SHSY5Y in 532 nm laser PBM. This shows that considerations on the differentiation state of cells is important in PBM studies. The hypothesis of difference in intracellular reactive oxygen species (ROS) accumulation from laser irradiation can serve as a versatile explanation of the observed difference in photobiological effect. Further investigation into the role of ROS as a mediator of various photobiological effects from laser of different wavelengths is warranted.


Assuntos
Diferenciação Celular , Terapia com Luz de Baixa Intensidade , Neuroblastoma , Humanos , Terapia com Luz de Baixa Intensidade/métodos , Diferenciação Celular/efeitos da radiação , Neuroblastoma/radioterapia , Neuroblastoma/patologia , Linhagem Celular Tumoral
2.
Soins Psychiatr ; 45(351): 33-36, 2024.
Artigo em Francês | MEDLINE | ID: mdl-38527871

RESUMO

Since the industrialization of tobacco production in the last century, tobacco has been a popular product in all walks of life. Its harmful effects, now well recognized, have led to the implementation of increasingly active health policies. Its place in public life is increasingly controlled. This approach aims to prevent the continuation of risky behaviours associated with its use. Hospitals are becoming a model for the denormalization of smoking.


Assuntos
Abandono do Hábito de Fumar , Humanos , Saúde Pública , Fumar , Hospitais
3.
Am J Drug Alcohol Abuse ; 50(2): 207-217, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38386811

RESUMO

Background: Numerous studies have highlighted the pivotal role of alterations in the monetary reward system in the development and maintenance of substance use disorder (SUD). Although these alterations have been well documented in various forms of SUD, the electrophysiological mechanisms specific to opioid use disorder (OUD) remain underexplored. Understanding these mechanisms is critical for developing targeted interventions and advancing theories of addiction specific to opioid use.Objectives: To explore abnormalities in monetary reward outcome processing in males with OUD. We hypothesized that control individuals would show higher feedback-related negativity (FRN) to losses, unlike those in the OUD group, where FRN to losses and gains would not differ significantly.Methods: Fifty-seven participants (29 male individuals with OUD [heroin] and 28 male controls) were evaluated. A combination of the monetary incentive delay task (MIDT) and event-related potential (ERP) technology was used to investigate electrophysiological differences in monetary reward feedback processing between the OUD and healthy control groups.Results: We observed a significant interaction between group (control vs. OUD) and monetary outcome (loss vs. gain), indicated by p < .05 and η2p = 0.116. Specifically, control participants showed stronger negative FRN to losses than gains (p < .05), unlike the OUD group (p > .05).Conclusion: This study's FRN data indicate that males with OUD show altered processing of monetary rewards, marked by reduced sensitivity to loss. These findings offer electrophysiological insights into why males with OUD may pursue drugs despite potential economic downsides.


Assuntos
Potenciais Evocados , Transtornos Relacionados ao Uso de Opioides , Recompensa , Humanos , Masculino , Adulto , Transtornos Relacionados ao Uso de Opioides/fisiopatologia , Potenciais Evocados/fisiologia , Estudos de Casos e Controles , Eletroencefalografia , Adulto Jovem , Motivação , Retroalimentação Psicológica/fisiologia
4.
Rev Infirm ; 72(296): 26-27, 2023 Dec.
Artigo em Francês | MEDLINE | ID: mdl-38071012

RESUMO

In France, as in other countries, more and more women are affected by alcoholism. Progress needs to be made in the early detection and management of their physical and psychological dependence on alcohol, as well as their psychopathological comorbidities.


Assuntos
Alcoolismo , Humanos , Feminino , Alcoolismo/diagnóstico , Alcoolismo/psicologia , Psicopatologia , França
5.
J Obstet Gynaecol Can ; 45(11): 102146, 2023 11.
Artigo em Francês | MEDLINE | ID: mdl-37977719

RESUMO

OBJECTIF: Présenter aux professionnels de la santé les données probantes concernant l'utilisation des opioïdes et la santé des femmes. Les domaines d'intérêt sont la grossesse et les soins post-partum. POPULATION CIBLE: Toutes les femmes qui utilisent des opioïdes. RéSULTATS: Un dialogue ouvert et éclairé sur l'utilisation des opioïdes améliorera les soins aux patientes. BéNéFICES, RISQUES ET COûTS: L'exploration de l'utilisation d'opioïdes par une approche tenant compte des traumatismes antérieurs donne au professionnel de la santé et à la patiente l'occasion de bâtir une alliance solide, collaborative et thérapeutique. Cette alliance permet aux femmes de faire des choix éclairés. Elle favorise le diagnostic et le traitement possible du trouble lié à l'utilisation d'opioïdes. L'utilisation ne doit pas être stigmatisée, puisque la stigmatisation affaiblit le partenariat (le partenariat entre patiente et professionnel de la santé). Les professionnels de la santé ceus-ci doivent comprendre l'effet potentiel des opioïdes sur la santé les femmes enceintes et les aider à prendre des décisions éclairées sur leur santé. DONNéES PROBANTES: Une recherche a été conçue puis effectuée dans les bases de données PubMed et Cochrane Library pour la période d'août 2018 à mars 2023 des termes MeSH et mots clés suivants (et variantes) : opioids, opioid agonist therapy, illicit drugs, fertility, pregnancy, fetal development, neonatal abstinence syndrome et breastfeeding. MéTHODES DE VALIDATION: Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant le cadre méthodologique GRADE (Grading of Recommendations, Assessment, Development, and Evaluation). Voir l'annexe A en ligne (tableau A1 pour les définitions et tableau A2 pour l'interprétation des recommandations fortes et conditionnelles [faibles]). PROFESSIONNELS CONCERNéS: Tous les professionnels de la santé qui prodiguent des soins aux femmes et aux nouveaux-nés. RéSUMé POUR TWITTER: La consommation d'opioïdes pendant la grossesse coïncide souvent avec des problèmes de santé mentale et est associée à des conséquences néfastes pour la mère, le fœtus et le nouveau-né ; le traitement des troubles liés à la consommation d'opioïdes par agonistes peut être sûr pendant la grossesse lorsque les risques sont plus nombreux que les avantages. DÉCLARATIONS SOMMAIRES: RECOMMANDATIONS.

6.
Brain Sci ; 13(7)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37509004

RESUMO

Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive, drug-free, neural-circuit-based therapeutic tool that was recently cleared by the United States Food and Drug Associate for the treatment of smoking cessation. TMS has been investigated as a tool to reduce consumption and craving for many other substance use disorders (SUDs). This review starts with a discussion of neural networks involved in the addiction process. It then provides a framework for the therapeutic efficacy of TMS describing the role of executive control circuits, default mode, and salience circuits as putative targets for neuromodulation (via targeting the DLPFC, MPFC, cingulate, and insula bilaterally). A series of the largest studies of TMS in SUDs are listed and discussed in the context of this framework. Our review concludes with an assessment of the current state of knowledge regarding the use of rTMS as a therapeutic tool in reducing drug, alcohol, and nicotine use and identifies gaps in the literature that need to be addressed in future studies. Namely, while the presumed mechanism through which TMS exerts its effects is by modulating the functional connectivity circuits involved in executive control and salience of drug-related cues, it is also possible that TMS has direct effects on subcortical dopamine, a hypothesis that could be explored in greater detail with PET imaging.

7.
J Frailty Aging ; 12(3): 236-243, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37493385

RESUMO

The vast majority of people living in long-term care facilities (LTCFs) are octogenarians (i.e., in Québec, 57.4% of the residents are age 85 or older, 26.2% are between age 75 and 84, 10.7% are between age 65 and 74, and 5.7% are below age 65 (1)), who are affected by a great loss of physical or cognitive autonomy due to illnesses and are unable to maintain their independence, safety and mobility at home. For the majority of them, their last living environment will be a LTCF. Moreover, the annual turnover in LTCFs is one-third of all residents (2) while the average length of stay is 823 days (1). Therefore the main challenges for caregivers in LTCFs are the maintenance of functional capacities and preventing patients from becoming bedridden and isolated. Measuring the level of autonomy and functional capacities is therefore a key element in the care of institutionalized people. Several validated tools are available to quantify the degree of dependence and the functional capacities of older people living in long-term care facilities. This narrative review aims to present the characteristics of the specific population living in long-term care facilities and describe the most widely used and validated tools to measure their level of autonomy and functional capacities.


Assuntos
Assistência de Longa Duração , Idoso de 80 Anos ou mais , Humanos , Idoso , Padrões de Referência , Quebeque
8.
Rev Infirm ; 72(290): 18-21, 2023 Apr.
Artigo em Francês | MEDLINE | ID: mdl-37088489

RESUMO

In the hospital, the geriatric missions of nurses and paramedical and medical teams are essential in order to benefit elderly patients and to fight against the immobilization syndrome through responsiveness and quality care. This care takes place in parallel with the specific medical care of the medical pathologies treated. In 2017, the High Authority for Health advocated good professional practices to avoid iatrogenic dependence of hospitalized elderly people. Through this article, we carry out a focus on the immobilization syndrome and its deleterious consequences: we must not do in the place of the elderly subject!


Assuntos
Idoso Fragilizado , Hospitais , Doença Iatrogênica , Idoso , Humanos , Hospitalização/estatística & dados numéricos , Hospitais/estatística & dados numéricos , Idoso de 80 Anos ou mais , Imobilização/estatística & dados numéricos , Síndrome , Idoso Fragilizado/estatística & dados numéricos
10.
Res Sq ; 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36711858

RESUMO

The aim of our study was to assess the overall survival rates for colorectal patients in Morocco and to identify strong prognostic factors using a novel approach combining survival random forest and the Cox model. Covariate selection was performed using the variable importance based on permutation and partial dependence plots were displayed to explore in depth the relationship between the estimated partial effect of a given predictor and survival rates. The predictive performance was measured by two metrics, the Concordance Index (C-index) and the Brier Score (BS). Overall survival rates at 1, 2 and 3 years were, respectively, 87% (SE = 0.02; CI-95% = 0.84-0.91), 77% (SE = 0.02; CI-95% = 0.73-0.82) and 60% (SE = 0.03; CI-95% = 0.54-0.66). In the Cox model after adjustment for all covariates, sex, tumor differentiation had no significant effect on prognosis, but rather tumor site had a significant effect. The variable importance obtained from RSF strengthens that surgery, stage, insurance, residency, and age were the most important prognostic factors. The discriminative capacity of the Cox PH and RSF was, respectively, 0.771 and 0.798 for the C-index, while the accuracy of the Cox PH and RSF was, respectively, 0.257 and 0.207 for the Brier Score. This shows that RSF had both better discriminative capacity and predictive accuracy. Our results show that patients who are older than 70, living in rural areas, without health insurance, at a distant stage and who have not had surgery constitute a subgroup of patients with poor prognosis.

11.
Encephale ; 49(3): 261-267, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35034791

RESUMO

OBJECTIVE: Several health issues related to the us of social networking sites (SNS) are documented. One concept that is not clearly studied is suggestibility as the tendency of a person to accept and internalize communication. The aim of the study is to test a model in which suggestibility of people can predict SNS use, which in turn can predict substance use. METHODS: Participants answered a questionnaire measuring suggestibility, alcohol consumption, dependence to nicotine and Facebook use. Linear regression and a structural equation model (SEM) were carried out to assess which utilization of Facebook variables explained best the level of alcohol consumption or nicotine dependence and to assess how suggestibility predicted Facebook use. RESULTS: Linear regression analyses indicate that only the number of friends on Facebook is a predictor of the level of alcohol consumption (P<0.001). Suggestibility predict the frequency of Facebook use (P<0.001) and of the number of friends on Facebook (P=0.022). The SEM demonstrates that participants with a higher level of suggestibility have more friends on the SNS, which can influence substance consumption. CONCLUSION: Individuals' level of suggestibility affects Facebook use. People with a higher level of suggestibility are more likely to have many friends on the SNS resulting in a possible environmental influence on substance use.


Assuntos
Comportamento Aditivo , Mídias Sociais , Humanos , Comunicação , Rede Social , Inquéritos e Questionários , Comportamento Aditivo/epidemiologia
12.
Ind Psychiatry J ; 32(Suppl 1): S157-S160, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38370938

RESUMO

Background: With the advent of smartphones, there is an exponential increase in mobile usage and addiction. The statistics pointing toward mobile dependence in adolescents are of paramount importance to assess the prevalence in them and suggest measures accordingly. Aim: To observe the usage and dependence among the degree college students in an industrial township. Materials and Methods: A validated and structured questionnaire was distributed among the students at a women's degree college in western Maharashtra and responses were collected after obtaining consent. Along with sociodemographic details, qualitative and quantitative information regarding mobile usage were collected. Data were cleaned, coded, and analyzed after ensuring the confidentiality of their information using SPSS v26.0. Results: The mean age of the participants was 18.9+/-1.8 years. The mean time spent on mobile was 2.4+/-0.4 hours per day. Mobile dependency was found in 48% of participants. The mean total score was 92. The primary purpose for using the internet was to browse (41%) and social media 36%. The main benefit of using the internet was searching for information urgently (62.5%). A major limitation of using was felt as the internet to be very slow 61 (42.3%). Conclusion: There is a high prevalence of smartphone dependence in college students.

13.
Encephale ; 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36528392

RESUMO

OBJECTIVES: Muscle dysmorphia (MD) is a disorder affecting mainly men and is characterized by significant dissatisfaction with muscles. The idea that MD could represent an addiction has been theoretically discussed, but no empirical data are available. Based on Foster et al. (2015) framework, the Addiction to Body Image Inventory (ABII) was developed. This study aims to validate the ABII and to evaluate its capacity to capture MD severity. METHODS: A first community sample of 466 participants was recruited and completed the ABII and questionnaires on MD and body esteem. A second sample of 47 men at risk of MD was recruited mostly in gyms and completed the ABII and questionnaires on MD, eating and psychological symptoms. RESULTS: With the community sample, the results showed that the ABII had a valid factorial structure, good internal consistency, and good convergent validity. With the sample of men at risk of MD, the results showed that the ABII had good convergent validity with MD and eating symptoms but not with psychological symptoms. The results of a regression model showed that the ABII explained 12% of the MD variance. CONCLUSIONS: This study brings the first measure of addiction to body image and suggests that MD must be understood as a complex phenomenon including eating symptoms and addictive tendencies.

14.
Rev Infirm ; 71(283): 39-42, 2022.
Artigo em Francês | MEDLINE | ID: mdl-36427941

RESUMO

Disability, a factor of vulnerability to incestThere is a lack of visibility on the issue of sexual violence among people with disabilities. There is an omerta on this subject within the social and medico-social establishments that receive them. Intra-family sexual violence is kept silent, as it is everywhere else. The vulnerability of children with disabilities is a risk factor for rape and sexual assault, and communication problems hinder their disclosure. Interview with Marie Rabatel, President of the Francophone Association of Autistic Women, expert of the High Authority of Health on the issues of violence against women with disabilities, member of the Independent Commission on incest and sexual violence against children.


Assuntos
Transtorno Autístico , Pessoas com Deficiência , Criança , Feminino , Humanos , Incesto , Violência , Processos Grupais
15.
Nutrients ; 14(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36364755

RESUMO

Despite the high prevalence of sports supplement (SS) use, efforts to profile users have not been conclusive. Studies report that 30-95% of recreational exercisers and elite athletes use SS. Research found has mostly focused on demographic and sports variables to profile SS users, but little research has studied the psychological factors that may influence the use of SS. The purpose of this investigation was to classify, describe, and differentiate the profile of users and non-users of SS, considering demographic, sports, and psychological variables. A total of 554 participants completed the questionnaire. Overall, 45% of recreational exercisers and elite athletes reported using supplements. There were significant differences found regarding the use of SS between men and women (51% vs. 49%, p = 0.002; OR = 1.799), and when training 4 or more days per week (p ≤ 0.001; OR = 1.526). Findings regarding the psychological variables have been found in the Adonis Complex. These results indicate that participants with greater concerns regarding physical appearance, tend to be SS users (p = 0.001; OR = 1.200). The results of this study fill a gap in previous research, and provide an approximate profile, including demographic, sports, and psychological variables of SS users.


Assuntos
Esportes , Masculino , Humanos , Feminino , Estudos Transversais , Esportes/psicologia , Suplementos Nutricionais , Atletas/psicologia , Inquéritos e Questionários , Prevalência
16.
Can J Physiol Pharmacol ; 100(12): 1135-1142, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36223654

RESUMO

The main side effects of opioid use are physiological and psychological dependence. The transient receptor potential channels, including transient receptor potential ankyrin 1 (TRPA1), are involved in various neurological disorders. We aimed to evaluate the effect of TRPA1 inhibition on morphine-induced conditioned place preference (CPP) and physical dependence. For induction of CPP, morphine (10 and 20 mg/kg) was administrated for four consecutive days to male BALB/c mice. The effects of HC030031 (TRPA1 antagonist, 10, 25, and 50 mg/kg) on the expression and reinstatement of morphine-induced CPP were evaluated. For induction of physical dependence, morphine was injected three times a day for 3 days. Withdrawal-related behaviors such as jumping and defecation were precipitated by the administration of naloxone to morphine-dependent mice. The effect of HC030031 on jumping and defecation was assessed. The results showed that 20 mg/kg of morphine elicited a significant CPP. HC030031 reduced the expression of morphine CPP without any change in the locomotor activity. It also decreased the reinstatement of morphine CPP. HC030031 mitigated morphine withdrawal via reducing jumping and defecation. The present study demonstrated that HC030031 decreased morphine-associated CPP and physical dependence. It is presumed that TRPA1 has interaction with the main pharmacological effects of morphine.


Assuntos
Dependência de Morfina , Morfina , Camundongos , Masculino , Animais , Morfina/farmacologia , Purinas , Acetanilidas
17.
J Dent Hyg ; 96(5): 37-41, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36224085

RESUMO

Tobacco use impacts every organ in the body. Dental professionals observe the detrimental oral and systemic consequences of tobacco use. Routine dental hygiene and dental appointments are an ideal opportunity for tobacco cessation discussions. Oral health care professionals can take the lead in assisting patients with evidence-based tobacco cessation strategies. Incorporation of tobacco cessation treatment within the curriculum of dental and dental hygiene programs will promote interprofessional tobacco cessation services. The purpose of this short report is to describe the process of introducing a Tobacco Treatment Specialist (TTS) program into the curricula of four health professional programs (dentistry, dental hygiene, pharmacy, and physician assistant) within a university health sciences center. Upon graduation, all involved students may qualify for TTS credentials. This report describes the importance of the interprofessional team, particularly dentists and dental hygienists, in the implementation of the first dental school-based certified tobacco treatment training program and incorporation of tobacco treatment content into interprofessional healthcare program curricula.


Assuntos
Higienistas Dentários , Abandono do Uso de Tabaco , Certificação , Currículo , Higienistas Dentários/educação , Humanos , Nicotiana , Uso de Tabaco
18.
Ann Pharm Fr ; 80(6): 897-905, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35667462

RESUMO

OBJECTIVES: To investigate attitude of community pharmacists toward patients with a substance-related disorder (heroin, alcohol and tobacco). MATERIAL AND METHODS: The attitudes were assessed thanks to the Attitude to Mental Illness Questionnaire (AMIQ) for heroin, alcohol and tobacco-related disorders in three independent groups of pharmacists. Estimation of substance-related harmfulness, knowledge of substance-related disorders and activities/needs for continuing education on substance-related disorders were also recorded. RESULTS: Thirty-five pharmacists were included (heroin: 11, alcohol: 10 and tobacco: 14). AMIQ scores for heroin-related disorder were negative and lower than for alcohol (P<0.01) and tobacco (P<0.001). AMIQ scores for alcohol-related disorder were lower than for tobacco (P<0.05). The estimation of heroin-related harmfulness was higher than for alcohol and tobacco (P<0.001). The estimations of knowledge of substance-related disorders were lower for opioid and alcohol than for tobacco (P<0.001). AMIQ scores and the needs for continuing education on each associated addiction showed a positive relation (P<0.01). CONCLUSION: Pharmacists had a negative attitude toward heroin and alcohol-related disorders. A positive attitude toward patients with a substance-related disorder was associated with a need for continuing education. Efforts should be made to change attitudes and to promote continuing education on heroin and alcohol-related disorders.


Assuntos
Transtornos Relacionados ao Uso de Álcool , Transtornos Relacionados ao Uso de Substâncias , Humanos , Heroína , Farmacêuticos , Estudos Transversais , Nicotiana , Analgésicos Opioides , Transtornos Relacionados ao Uso de Substâncias/complicações , Etanol , Educação Continuada , Atitude , Atitude do Pessoal de Saúde
19.
Therapie ; 77(6): 673-681, 2022.
Artigo em Francês | MEDLINE | ID: mdl-35697536

RESUMO

Ethanol is an excipient with known effect whose presence is regulated because it can cause adverse effects, notably a misuse. In order to raise awareness of this risk, this study searched all oral drugs with ethanol as an excipient from the Theriaque® database. All drugs marketed in France with a unit dose ethanol intake of 0.1g or more were identified and analyzed, according to the maximum unit and daily dosage recommended by the manufacturer. This research revealed 106 pharmaceutical specialties responsible for a unit intake of ethanol of 0.1g or more among the 8532 oral drugs containing ethanol (1.2 %): 2 at a daily dose >13g and the majority (57/106; 54 %) at a daily dose <1g. These are mainly oral solutions (97/106; 91 %) of phytotherapy (45/97; 46 %). The most frequently found therapeutic class was antitussive (12/106; 11 %). The majority of drugs are over-the-counter medication (56/106; 53 %). Overall, 106 drugs on the French market can be associated with a risk of misuse and cause adverse effects in vulnerable populations such as children and pregnant women. Vigilance and appropriate monitoring is required for these drugs (especially those over-the-counter ones), and their substitution should be preferred if possible.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Excipientes , Gravidez , Criança , Humanos , Feminino , Excipientes/efeitos adversos , Etanol/efeitos adversos , Bases de Dados Factuais , França/epidemiologia
20.
Int J Mol Sci ; 23(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35742916

RESUMO

Cytosine methylation within the 5'-C-phosphate-G-3' sequence of nucleotides (called CpG methylation) is a well-known epigenetic modification of genomic DNA that plays an important role in gene expression and development. CpG methylation is likely to be altered in the CpG islands. CpG islands are rich in cytosine, forming a structure called the i-motif via cytosine-cytosine hydrogen bonding. However, little is known about the effect of CpG methylation on the i-motif. In this study, The CpG methylation-induced structural changes on the i-motif was examined by thermal stability, circular dichroism (CD) spectroscopy, and native-polyacrylamide gel electrophoresis (Native-PAGE) evaluation of five i-motif-forming DNAs from four cancer-related genes (VEGF, C-KIT, BCL2, and HRAS). This research shows that CpG methylation increased the transitional pH of several i-motif-forming DNAs and their thermal stability. When examining the effect of CpG methylation on the i-motif in the presence of opposite G4-forming DNAs, CpG methylation influenced the proportion of G4 and i-motif formation. This study showed that CpG methylation altered the stability and structure of the i-motif in CpG islands.


Assuntos
Citosina , Quadruplex G , Ilhas de CpG , Citosina/metabolismo , DNA/química , Metilação de DNA , Epigênese Genética
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