Practice, barriers, and facilitators of healthcare providers in smoking cessation in Mexico.

OBJECTIVE: To assess the clinical practice, barriers, and facilitators in promoting smoking cessation in primary healthcare clinics in Mexico City. MATERIALS AND METHODS: A mixed method design was used. Surveys (n = 70) and semi-structured interviews (n = 9) were conducted with health personnel involved in smoking cessation clinics. RESULTS: Quantitative data revealed that physicians were more likely than nurses to 1) ask patients if they smoke (57.9% vs 34.5%, p = .057), 2) ask patients if they are interested in quitting smoking (65.7% vs 26.9%, p = .003), 3) provide advice to quit smoking (54.3% vs 29.2%, p = .056), and 4) assess whether pharmacotherapy is needed (21.9% vs 10%, p = .285). Qualitative data showed that nurses were more likely than physicians to report lack of resources to refer patients to smoking cessation services, lack of pharmacotherapy availability, and lack of provider training in smoking cessation. Reported barriers include lack of motivation among patients, lack of time for assessment, long appointment wait times, and lack of training. Reported facilitators include existence of smoking cessation programmes and pharmacotherapy at no cost to the patient, and having a multidisciplinary team. CONCLUSIONS: Due to numerous barriers, smoking cessation interventions are partially implemented in primary care clinics in Mexico City. A restructuring of services is necessary, and nurses should be given a more prominent role.

High Frequency and Low Intensity Transcranial Magnetic Stimulation for Smoking Cessation.

INTRODUCTION: Tobacco consumption is one of the main causes of mortality in the world. Because of its effect on health, smoking cessation should be prioritized as an important health intervention; however, current interventions have shown low success rates as only 31% of the cases can stop smoking. In this paper, an intervention with high frequency and low intensity transcranial magnetic stimulation (HFLI TMS) was applied to determine if this type of neuromodulation could have an effect in decreasing tobacco addiction. METHODS: Retrospective data from ten ambulatory smoker patients that underwent 24 sessions of HFLI TMS over 8 weeks were retrieved and are here presented. RESULTS: Exhaled CO concentrations were statistically significantly different from baseline at the weeks 3, 5, 6, and 8. After the 24 sessions, all patients stopped smoking; this was confirmed directly by exhaled carbon monoxide and the smoking diary. Three months after intervention, eight out of ten subjects continued without smoking. No severe adverse effects were reported by participants. CONCLUSIONS: Overall, employing HFLI TMS appears to have acceptable result; however, further evidence is needed to determine with more certainty its therapeutic effect and adverse effects for addiction intervention.

Gender-related beliefs and attitudes about tobacco use and smoking cessation in Mexico.

BACKGROUND: While overall trends in tobacco use among men are declining, tobacco use continues to rise significantly among women in developing countries. This study aimed to explore the gender-related beliefs and attitudes about tobacco use and smoking cessation in Mexico, one of the top five Latin America countries with the highest prevalence of tobacco consumption. MATERIALS AND METHODS: This study was conducted using an explanatory qualitative methods design. Semi-structured interviews were conducted with 14 adults smokers (8 women & 6 men) who visited primary healthcare clinics in Mexico City. Two researchers independently coded the interviews and applied the final codes upon consensus. Inter-rater reliability was assessed for four groups of codewords (92% agreement), based on an ecological model on socio-cultural factors. FINDINGS: Initiation to smoking in women begins out of curiosity, and in men by imitation. Also, women start using tobacco at an older age compared to men. During maintenance of smoking, women report experiencing loneliness and anxiety about multiple responsibilities, e.g. women reveal that they feel guilty when they smoke due to their maternal role as caregivers. Additionally, some women report that smoking is a symbol of freedom, recalling the media messages associated with promoting tobacco products. Among men, the results show that they smoke for pleasure and to socialize, and consider that women smoke to imitate men and feel powerful. Regarding cessation, women are ambivalent about quitting smoking or not, and men mention not needing professional support. For organizational barriers, women mention the cost of treatment and men, the distance to clinics. CONCLUSION: Smoking cessation interventions should be proposed from an approach that involves changes in social norms, seeking a more equitable relationship between men and women. Therefore, there must be broad engagement from different sectors and not just at the health sector level.

Lung Damage Caused by Heated Tobacco Products and Electronic Nicotine Delivery Systems: A Systematic Review.

The tobacco industry promotes electronic nicotine delivery systems (ENDS) and heated tobacco products (HTP) as a safer alternative to conventional cigarettes with misleading marketing sustained by studies with conflict of interest. As a result, these devices sell without regulations and warnings about their adverse effects on health, with a growing user base targeting young people. This systematic review aimed to describe the adverse effects on the respiratory system in consumers of these devices. We conducted a systematic review and bibliometric analysis of 79 studies without conflict of interest evaluating ENDS and HTP effects in the respiratory system in experimental models, retrieved from the PubMed database. We found that the damage produced by using these devices is involved in pathways related to pulmonary diseases, involving mechanisms previously reported in conventional cigarettes as well as new mechanisms particular to these devices, which challenges that the tobacco industry's claims. The present study provides significant evidence to suggest that these devices are an emerging public health problem and that they should be regulated or avoided.

Efectos en la salud de los sistemas electrónicos de administración de nicotina (SEAN) / Health Effects of Electronic Nicotine Delivery Systems (SEAN)

Resumen Sin lugar a dudas, el tabaquismo continúa siendo la principal causa de enfermedad, discapacidad y muerte prematura a nivel mundial. Sin embargo, el advenimiento de los nuevos sistemas electrónicos de administración de nicotina (SEAN), entre los que destaca el cigarrillo electrónico, ha tenido un crecimiento explosivo y en algunos países ha desplazado a los cigarrillos de tabaco, especialmente entre los jóvenes que se sienten atraídos por sus llamativos sabores y por el despliegue de tecnología que se utiliza en su diseño y funcionamiento. Los SEAN surgieron inicialmente en 2003 como una supuesta ayuda para dejar de fumar, a 16 años de esta fecha no hay estudios clínicos que confirmen su superioridad sobre los medicamentos existentes para tal fin: terapias de reemplazo de nicotina, bupropión y vareniclina, ni sobre las terapias psicológicas como la racional emotiva y la cognitivo conductual. Por el contrario, se han acumulado gran cantidad de evidencias sobre el efecto deletéreo que tienen sobre la salud de los consumidores, el riesgo que representan es indudable y esto se confirma por reportes recientes de Centros de Control de Enfermedades de los Estados Unidos (CDC) que señalan 2,172 casos hospitalizados con enfermedad pulmonar aguda y 42 muertes por esta causa, siendo el 79% personas menores de 35 años. Este brote de enfermedad pulmonar ha determinado que se plantee la prohibición de los SEAN en Estados Unidos. Asimismo, la Food and Drug Administration (FDA) aprobó la venta de los cigarrillos híbridos o heets que utilizan tabaco calentado, los cuales ya están disponibles en nuestro país. No cabe duda de que como profesionales del área de la salud nuestra obligación es informar con evidencias científicas sobre los riesgos que representan los SEAN para sus consumidores, asimismo debemos aprender de la historia del tabaquismo para poder prevenir la morbimortalidad asociada con estos nuevos productos del tabaco.

Abstract Without a doubt, smoking continues to be the leading cause of disease, disability, and premature death worldwide. However, the advent of the new Electronic Administration Systems of Nicotine (SEAN), among which the electronic cigarette stands out, has had explosive growth and in some countries has depleted tobacco cigarettes, especially among young people who feel attracted by its striking flavors and the deployment of technology that is used in its design and operation. The SEANs initially emerged in 2003 as a supposed help to quit smoking, at 16 years from this date no clinical studies are confirming their superiority over existing medications for this purpose: nicotine, bupropion and varenicline replacement therapies, or over psychological therapies such as emotional and cognitive-behavioral rational. On the other side, a large amount of evidence has been accumulated on the deleterious effect they have on the health of consumers, the risk they represent is unquestionable and this is confirmed by recent reports from the Centers for Disease Control of the United States (CDC) that indicate 2142 hospitalized cases with acute lung disease and 42 deaths from this cause, 79% being people under 35 years. This outbreak of lung disease has determined that the ban on SEAN in the United States will be planted. Also, the Food and Drug Administration (FDA) approved the sale of hybrid cigarettes or "Heets" (Heat-not-burn tobacco products), which uses heated tobacco, and are now available in our country. There is no doubt that as health professionals, we must inform with scientific evidence about the risks that SEANs pose to their consumers, we must also learn from the history of smoking to prevent the morbidity and mortality associated with these new tobacco products.

The mechanism of dysbiosis in alcoholic liver disease leading to liver cancer.

Currently, alcoholic liver disease (ALD) is one of the most prevalent chronic liver diseases worldwide, representing one of the main etiologies of cirrhosis and hepatocellular carcinoma (HCC). Although we do not know the exact mechanisms by which only a selected group of patients with ALD progress to the final stage of HCC, the role of the gut microbiota within the progression to HCC has been intensively studied in recent years. To date, we know that alcohol-induced gut dysbiosis is an important feature of ALD with important repercussions on the severity of this disease. In essence, an increased metabolism of ethanol in the gut induced by an excessive alcohol consumption promotes gut dysfunction and bacterial overgrowth, setting a leaky gut. This causes the translocation of bacteria, endotoxins, and ethanol metabolites across the enterohepatic circulation reaching the liver, where the recognition of the pathogen-associated molecular patterns via specific Toll-like receptors of liver cells will induce the activation of the nuclear factor kappa-B pathway, which releases pro-inflammatory cytokines and chemokines. In addition, the mitogenic activity of hepatocytes will be promoted and cellular apoptosis will be inhibited, resulting in the development of HCC. In this context, it is not surprising that microbiota-regulating drugs have proven effectiveness in prolonging the overall survival of patients with HCC, making attractive the implementation of these drugs as co-adjuvant for HCC treatment.

The cellular pathways of liver fibrosis in non-alcoholic steatohepatitis.

Non-alcoholic steatohepatitis (NASH) is considered the advanced stage of non-alcoholic fatty liver disease (NAFLD). It is characterized by liver steatosis, inflammation and different degrees of fibrosis. Although the exact mechanisms by which fatty liver progresses to NASH are still not well understood, innate and adaptive immune responses seem to be essential key regulators in the establishment, progression, and chronicity of these disease. Diet-induced lipid overload of parenchymal and non-parenchymal liver cells is considered the first step for the development of fatty liver with the consequent organelle dysfunction, cellular stress and liver injury. These will generate the production of pro-inflammatory cytokines, chemokines and damage-associated molecular patterns (DAMPs) that will upregulate the activation of Kupffer cells (KCs) and monocyte-derived macrophages (MMs) favoring the polarization of the tolerogenic environment of the liver to an immunogenic phenotype with the resulting transdifferentiation of hepatic stellate cells (HSCs) into myofibroblasts developing fibrosis. In the long run, dendritic cells (DCs) will activate CD4+ T cells polarizing into the pro-inflammatory lymphocytes Th1 and Th17 worsening the liver damage and inflammation. Therefore, the objective of this review is to discuss in a systematic way the mechanisms known so far of the immune and non-proper immune liver cells in the development and progression of NASH.

[Evaluation of physical and psychological dependence in Mexican adult smokers, Encodat 2016.] / Evaluación de la dependencia física y psicológica al tabaco en fumadores mexicanos adultos, Encodat 2016.

OBJECTIVE: To evaluate the physical and psychological dependence to tobacco of Mexican smokers and its association with physical, psychological and social factors. MATERIALS AND METHODS: The 2016 National Alcohol and Tobacco Drug Consumption Survey (n=7 331) was analyzed using the Fagerström nicotine physical dependence scale (FTND) and the short scale of psychological dependence on tobacco (TAPDSc). Bivariate analyzes and generalized ordinal logistic regressions were performed to evaluate the associated factors. RESULTS: 82.3% of daily smokers and 98.8% of occasional smokers reported mild physical dependence, while 47.9 and 37.9% respectively reported moderate psychological dependence. The age of initiation of tobacco use, drug use, high alcohol consumption and high emotional distress were associated with high levels of psychological dependence in all smokers. CONCLUSIONS: The exclusive use of FTND does not allow to adequately evaluate Mexican smokers. The physical and psychological dependence on tobacco should be assessed with independent and validated scales in this population.

OBJETIVO: Evaluar la dependencia física y psicológica de los fumadores mexicanos y su asociación con factores físicos, psicológicos y sociales. MATERIAL Y MÉTODOS: . A partir de la Encuesta Nacional de Consumo de Drogas, Alcohol y Tabaco 2016 (n=7 331), se analizó la escala de dependencia física a la nicotina de Fagerström (FTND) y la escala corta de dependencia psicológica al tabaco (TAPDSc). Se realizaron análisis bivariados y regresiones logísticas ordinales generalizadas para evaluar los factores asociados. RESULTADOS: 82.3% de fumadores diarios y 98.8% de ocasionales reportaron dependencia física leve, mientras que 47.9 y 37.9%, respectivamente, presentaron dependencia psicológica moderada. La edad de inicio temprana de consumo de tabaco, uso de drogas, consumo alto de alcohol y malestar emocional se asociaron con niveles altos de dependencia psicológica en todos los fumadores. CONCLUSIONES: El uso exclusivo de FNTD no permite evaluar adecuadamente a los fumadores mexicanos. La dependencia física y psicológica al tabaco debe ser diagnosticada con escalas independientes y validadas en esta población.

Evaluación de la dependencia física y psicológica al tabaco en fumadores mexicanos adultos, Encodat 2016 / Evaluation of physical and psychological dependence in Mexican adult smokers, Encodat 2016

Resumen: Objetivo: Evaluar la dependencia física y psicológica de los fumadores mexicanos y su asociación con factores físicos, psicológicos y sociales. Material y métodos: A partir de la Encuesta Nacional de Consumo de Drogas, Alcohol y Tabaco 2016 (n=7 331), se analizó la escala de dependencia física a la nicotina de Fagerström (FTND) y la escala corta de dependencia psicológica al tabaco (TAPDSc). Se realizaron análisis bivariados y regresiones logísticas ordinales generalizadas para evaluar los factores asociados. Resultados: 82.3% de fumadores diarios y 98.8% de ocasionales reportaron dependencia física leve, mientras que 47.9 y 37.9%, respectivamente, presentaron dependencia psicológica moderada. La edad de inicio temprana de consumo de tabaco, uso de drogas, consumo alto de alcohol y malestar emocional se asociaron con niveles altos de dependencia psicológica en todos los fumadores. Conclusión: El uso exclusivo de FNTD no permite evaluar adecuadamente a los fumadores mexicanos. La dependencia física y psicológica al tabaco debe ser diagnosticada con escalas independientes y validadas en esta población.

Abstract: Objective: To evaluate the physical and psychological dependence to tobacco of Mexican smokers and its association with physical, psychological and social factors. Materials and methods: The 2016 National Alcohol and Tobacco Drug Consumption Survey (n=7 331) was analyzed using the Fagerström nicotine physical dependence scale (FTND) and the short scale of psychological dependence on tobacco (TAPDSc). Bivariate analyzes and generalized ordinal logistic regressions were performed to evaluate the associated factors. Results: 82.3% of daily smokers and 98.8% of occasional smokers reported mild physical dependence, while 47.9 and 37.9% respectively reported moderate psychological dependence. The age of initiation of tobacco use, drug use, high alcohol consumption and high emotional distress were associated with high levels of psychological dependence in all smokers. Conclusion: The exclusive use of FTND does not allow to adequately evaluate Mexican smokers. The physical and psychological dependence on tobacco should be assessed with independent and validated scales in this population.

"Vive Sin Tabaco ¡Decídete!" Feasibility and Acceptability of an e-Health Smoking Cessation Informed Decision-Making Tool Integrated in Primary Healthcare in Mexico.

Introduction:While smoking remains one of the leading causes of death in Mexico, uptake of evidence-based cessation therapy remains low. Widespread use of mobile devices and internet in Mexico has created new avenues for providing access to cessation treatment.Methods:We assessed the feasibility and acceptability of "Vive Sin Tabaco… ¡Decídete!" (English: Live without Tobacco…. Decide!), a web-based, informed decision-making tool designed to help Mexican smokers develop a quit plan and take advantage of cessation resources. We invited 164 smokers in two primary care clinics. Measures included physical, situational, and psychological nicotine dependence, interest in using pharmacotherapy and counseling, smoking status at 3 months, and satisfaction with the program.Results:Most participants were light smokers and reported low-to-moderate nicotine dependence. Immediately after using ¡Vive Sin Tabaco… ¡Decídete!, the majority were interested in quitting, set a quit date, and reported interest in using pharmacotherapy and cessation counseling. Follow-up rate at 3 months was 81.5%; seven-day point prevalence abstinence was 19.1% using intention-to-treat analysis.Conclusion:Integration of e-Health tools in primary healthcare settings has the potential to improve knowledge about cessation treatments among smokers and integrate smoking cessation into routine of care.

Enhancing smoking cessation in Mexico using an e-Health tool in primary healthcare.

OBJECTIVE: To evaluate an e-Health tool designed to enhance smoking cessation in Mexico in primary healthcare. MATERIALS AND METHODS: Smokers 18 years of age and older were recruited in the waiting room of two primary healthcare clinics in Mexico City. Participants used an eHealth smoking cessation tool that included smoking-related assessments, education on pharmacotherapy, and motivational videos. A follow-up assessment was conducted at 12 weeks week on smoking status. Logistic regression models were performed to identify factors associated with smoking cessation or consumption reduction. RESULTS: A total of 132 smokers were enrolled in the study. At follow-up, 23.5% of participants self-reported smoking cessation. Among those who did not quit smoking, 65.0% decreased the number of cigarettes. Factors associated significantly with smoking cessation were: being a non-daily smoker, being interested in quitting smoking, having low level of physical dependence, and participating in cessation treatment. CONCLUSIONS: The e-Health tool produced a high rate of smoking cessation. Better outcomes are obtained when this tool is used with conventional cessation programs.

Enhancing smoking cessation in Mexico using an e-Health tool in primary healthcare / Uso de una herramienta electrónica para la cesación del tabaquismo en el primer nivel de atención en México

Abstract: Objective: To evaluate an e-Health tool designed to enhance smoking cessation in Mexico in primary healthcare. Materials and methods: Smokers 18 years of age and older were recruited in the waiting room of two primary healthcare clinics in Mexico City. Participants used an e-Health smoking cessation tool that included smoking-related assessments, education on pharmacotherapy, and motivational videos. A follow-up assessment was conducted at 12 weeks week on smoking status. Logistic regression models were performed to identify factors associated with smoking cessation or consumption reduction. Results: A total of 132 smokers were enrolled in the study. At follow-up, 23.5% of participants self-reported smoking cessation. Among those who did not quit smoking, 65.0% decreased the number of cigarettes. Factors associated significantly with smoking cessation were: being a non-daily smoker, being interested in quitting smoking, having low level of physical dependence, and participating in cessation treatment. Conclusions: The e-Health tool produced a high rate of smoking cessation. Better outcomes are obtained when this tool is used with conventional cessation programs.

Resumen: Objetivo: Evaluar una herramienta electrónica diseñada para promover la cesación tabáquica en México en el primer nivel de atención. Material y métodos: Fumadores de 18 años de edad o más fueron reclutados en el área de espera de dos unidades de atención primaria en la Ciudad de México. Los participantes utilizaron una herramienta interactiva para dejar de fumar que incluía cuestionarios relacionados con el tabaquismo, educación sobre tratamientos farmacológicos y videos motivacionales. Una evaluación de seguimiento acerca de consumo de tabaco se realizó a las 12 semanas. Se realizaron modelos de regresión logística para identificar los factores asociados con cesación tabáquica o reducción de consumo. Resultados: Un total de 132 fumadores se inscribieron al estudio. Al seguimiento, 23.5% de los participantes autorreportaron cesación tabáquica. Entre quienes no cesaron, 65.0% redujo su consumo de cigarros al día. Los factores asociados significativamente con cesación tabáquica fueron ser un fumador ocasional, estar interesado en cesar, tener un bajo nivel de dependencia física y participar en tra tamientos de cesación. Conclusión: La herramienta electrónica produjo una alta tasa de cesación. Mejores resultados se obtienen cuando la herramienta se utiliza con programas de cesación convencionales.

Thrombosis of the Portal Venous System in Cirrhotic vs. Non-Cirrhotic Patients.

INTRODUCTION AND AIM: Thrombosis is a vascular disorder of the liver often associated with significant morbidity and mortality. Cirrhosis is a predisposing factor for portal venous system thrombosis. The aim of this study is to determine differences between cirrhotics and non-cirrhotics that develop thrombosis in portal venous system and to evaluate if cirrhosis severity is related to the development of portal venous system thrombosis. MATERIAL AND METHODS: We studied patients diagnosed with portal venous system thrombosis using contrast-enhanced computed tomography scan and doppler ultrasound at Medica Sur Hospital from 2012 to 2017. They were categorized into two groups; cirrhotics and non-cirrhotics. We assessed the hepatic function by Child-Pugh score and model for end-stage liver disease. RESULTS: 67 patients with portal venous system thrombosis (25 with non-cirrhotic liver and 42 with cirrhosis) were included. The mean age (± SD) was 65 ± 9.5 years in cirrhotic group and 57 ± 13.2 years (p = 0.009) in non-cirrhotic group. Comparing non-cirrhotics and cirrhotics, 8 non-cirrhotic patients showed evidence of extra-hepatic inflammatory conditions, while in the cirrhotic group no inflammatory conditions were found (p < 0.001). 27 (64.29%) cirrhotic patients had thrombosis in the portal vein, while only 9 cases (36%) were found in non-cirrhotics (p = 0.02). CONCLUSIONS: In cirrhotic patients, hepatocellular carcinoma and cirrhosis were the strongest risk factors to develop portal venous system thrombosis. In contrast, extrahepatic inflammatory conditions were main risk factors associated in non-cirrhotics. Moreover, the portal vein was the most frequent site of thrombosis in both groups.

More Evidence for the Genetic Susceptibility of Mexican Population to Nonalcoholic Fatty Liver Disease through PNPLA3.

BACKGROUND: The gene for patatin-like phospholipase domain containing 3 (PNPLA3) is associated with nonalcoholic fatty liver disease (NAFLD) development. We previously found that Mexican indigenous population had the highest frequency reported of the PNPLA3 148M risk allele. Further, we observed a relationship between M148M genotype with elevated ALT levels in individuals with normal weight, overweight and obese. We sought to investigate whether PNPLA3 polymorphism is associated with NAFLD development in Mexicans. MATERIAL AND METHODS: We enrolled 189 Mexican patients with NAFLD and 201 healthy controls. Anthropometric, metabolic, and biochemical variables were measured, and rs738409 (Ile148Met substitution) polymorphism was genotyped by sequencing. RESULTS: Logistic regression analysis, using a recessive model, suggested that PNPLA3 polymorphism in Mexican population is significantly associated (OR = 1.711, 95% CI: 1.014-2.886; P = 0.044) with NAFLD. CONCLUSIONS: The PNPLA3 gene is associated with NAFLD in Mexican population. More studies are required to explain the high prevalence of PNPLA3 polymorphism in Mexican-Americans, Mexican-Indians, and Mexican-Mestizos.

Prevalence of hepatitis C virus infection among patients undergoing haemodialysis in Latin America.

Hepatitis C infection is a worldwide problem. The global prevalence of the hepatitis C virus (HCV) averages 3%. Moreover, its prevalence among patients undergoing haemodialysis (HD) varies worldwide, ranging from as low as 1% to up to 70%. There are few data on its prevalence in developing countries, and even less information is available on HD patients. A literature review revealed that the prevalence of HCV infection among patients undergoing HD in Latin America ranges from 4.2 to 83.9%, with most data stemming from Argentina, Brazil, Mexico, Peru, Chile, Venezuela and Cuba. The most common genotype was genotype 1, and subtype 1b was the most frequent. The risk factors associated with this condition were the duration of the HD treatment and blood transfusion before hepatitis C screening. In addition, HCV RNA detection by polymerase chain reaction is crucial for the diagnosis of HCV infection in HD patients. Trials using combinations of new oral antiviral drugs, such as sofosbuvir and combo (ombitasvir, paritaprevir, ritonavir and dasabuvir), should be the next step in the improvement of care among HD patients with HCV, because these therapeutic agents apparently do not require dose adjustment according to renal function. Finally, information on this subgroup of patients remains unavailable in some countries; therefore, additional studies are needed to determine the prevalence trend of HCV infection in these populations.

The Role of Epigenetics in the Progression of Non-Alcoholic Fatty Liver Disease.

Non-alcoholic fatty liver disease encompasses a spectrum of pathologies ranging from simple steatosis to non-alcoholic steatohepatitis. Patients with non-alcoholic steatohepatitis have increased risk of cirrhosis, liver failure and hepatocellular carcinoma. About 25% of subjects with simple steatosis progress to steatohepatitis; nowadays, the detailed pathological factors influencing the progression of non-alcoholic fatty liver disease remains unclear. It is proposed that genetic and environmental factors interact to determine the disease phenotype. Epigenetics could explain some relationships between genes and external influences. The epigenetic changes that have been related to non-alcoholic fatty liver disease are DNA methylation, onecarbon metabolism, histone modifications and the presence of micro-RNA. DNA methylation and micro-RNAs have been investigated in human samples, whereas histone modifications have only been studied until now in animal and cellular models. The aim of this study is to review the most relevant information about epigenetic changes in non-alcoholic steatohepatitis.

The nuclear receptor FXR, but not LXR, up-regulates bile acid transporter expression in non-alcoholic fatty liver disease.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. Patients with non-alcoholic steatohepatitis (NASH) have increased plasmatic and hepatic concentrations of bile acids (BA), suggesting that they can be associated with the progression of the disease. Hepatic nuclear receptors are known to modulate genes controlling BA metabolism; thus, in this work we aimed to compare the expression of liver nuclear receptors -farnesoid X (FXR), small heterodimer partner (SHP) and liver X alpha (LXRα) receptors- and BA transporters -sodium+/taurocholate cotransporting polypeptide (NTCP) and bile salt export pump (BSEP)- in liver biopsy samples of patients with simple steatosis (SS) and NASH. MATERIAL AND METHODS: Forty patients with biopsy-proven NALFD were enrolled between 2009 and 2012; liver biopsies were classified as SS (N = 20) or NASH (N = 20) according to the NAFLD activity score. Gene expression of nuclear FXR, LXRα, SHP, NTCP and BSEP was analyzed by real-time reverse transcription polymerase chain reaction and protein level was quantified by western blot. RESULTS: Gene expression of FXR, SHP, NTCP and BSEP was significantly up-regulated in the NASH group in comparison with SS patients (P < 0.05). In contrast, protein level for FXR, SHP and NTCP was decreased in the NASH patients vs. the SS group (P < 0.05). Gene and protein profile of LXRα did not show differences between groups. CONCLUSIONS: The results suggest that liver nuclear receptors (FXR and SHP) and BA transporters (NTCP and BSEP) are associated with the progression of NAFLD.

Early changes in the components of the metabolic syndrome in a group of smokers after tobacco cessation.

AIM: We aimed to examine the prevalence of early changes in some components of metabolic syndrome after smoking cessation. METHODS: Forty-eight heavy smokers from the Tobacco Cessation Clinic (24 women/24 men), average age of 49.4 years, were included in this study. They smoked a mean of 19.92 cigarettes per day and had smoked 33.23 packages per year during 33.4 years. Participants were included in a treatment group based on cognitive behavior therapy (CBT); 16 participants received varenicline and the other 16 nicotine replacement therapy (NRT). The target quit day was scheduled for week 3 through abrupt cessation. Abstinence was confirmed with exhaled carbon monoxide (CO) levels. Blood pressure, body mass index (BMI), and waist circumference (WC) were evaluated weekly. Glucose, triglycerides, high density lipoproteins (HDL-C), and insulin to determine the homeostasis model assessment (HOMA) index were determined in blood samples at weeks 1, 4, and 10. As a control group 96 healthy nonsmokers were matched by age and sex. RESULTS: The mean BMI in smokers was 26.94 kg/m(2) and in nonsmokers 26.23 kg/m(2). Smokers showed hypertension, hypertriglyceridemia, and lower levels of HDL-C than nonsmokers. Percentages of cessation in week 3 were 81% for NRT and 93% for CBT and varenicline. The mean weight increase at the end of the treatment was 1.09 kg in the CBT group, 1.06 kg in the NRT group, and 1.17 kg in the varenicline group. The prevalence of metabolic syndrome was 31.25% in week 1 and 29.16% at the end. There were reductions in the number of subjects with hypertension, glucose alterations, hypertriglyceridemia, and low HDL levels. CONCLUSIONS: Benefits of quitting smoking exceeded by far the risks associated with the amount of weight gained.

The prevalence of nonalcoholic fatty liver disease in the Americas.

Nonalcoholic fatty liver disease (NAFLD) is an alarming public health problem. The disease is one of the main causes of chronic liver disease worldwide and is directly linked to the increased prevalence of obesity and type 2 diabetes mellitus (T2DM) in the general population. The worldwide prevalence of NAFLD has been estimated at 20-30%, but the prevalence is unknown in the Americas because of a lack of epidemiological studies. However, given the trends in the prevalence of diabetes and obesity, the prevalence of NAFLD and its consequences are expected to increase in the near future. The aim of the present study is to present the current data on the prevalence of NAFLD in the Americas. We performed an electronic search of the main databases from January 2000 to September 2013 and identified 356 reports that were reviewed. We focused on the epidemiology and prevalence of known NAFLD risk factors including obesity, T2DM, and the metabolic syndrome (MS). The prevalence of the MS was highest in the United States, Mexico, Costa Rica, Puerto Rico, Chile, and Venezuela. In addition, Puerto Rico, Guyana, and Mexico have the highest prevalence of T2DM in the Americas, while USA has the most people with T2DM. In conclusion, the prevalence rates of NAFLD and obesity were highest in the United States, Belize, Barbados, and Mexico.

Metabolic syndrome and nonalcoholic fatty liver disease. The role of endothelial progenitor cells.

BACKGROUND: Endothelial dysfunction has been previously described in metabolic syndrome patients. The levels of circulating endothelial progenitor cells (EPCs) inversely correlates with the incidence of cardiovascular disease. The aim of this study was to investigate the association between NAFLD, metabolic syndrome and EPC levels. MATERIAL AND METHODS: A cross-sectional pilot study was performed at a university hospital in Mexico. Two groups of patients without previously known chronic diseases were studied and classified according to the presence of NAFLD. Anthropometric, dietary, and biochemical variables, and circulating EPC number were measured and compared between the groups. RESULTS: Forty subjects were included and classified into two groups: patients with NAFLD (n = 20) and a control group (n = 20). The overall prevalence of insulin resistance and metabolic syndrome was 25% and 17.5%, respectively. EPC levels were found to be higher in the NAFLD group (p < 0.05) as in the patients with insulin resistance (p < 0.01) and metabolic syndrome (p < 0.01). These levels showed correlation with the severity of steatosis. CONCLUSIONS: Patients with NAFLD have increased levels of EPC, such levels are associated with the severity of NAFLD. These findings may suggest that these cells may play a role in the early natural history of NAFLD. EPC might be increased in an attempt to repair the endothelial damage resulting from metabolic alterations accompanying NAFLD. Further studies are needed to establish the dynamics of these cells in NAFLD.