State of the Art of Genomic Technology in Toxicology: A Review.

The rapid growth of genomics techniques has revolutionized and impacted, greatly and positively, the knowledge of toxicology, ushering it into a "new era": the era of genomic technology (GT). This great advance permits us to analyze the whole genome, to know the gene response to toxicants and environmental stressors, and to determine the specific profiles of gene expression, among many other approaches. The aim of this work was to compile and narrate the recent research on GT during the last 2 years (2020-2022). A literature search was managed using the PubMed and Medscape interfaces on the Medline database. Relevant articles published in peer-reviewed journals were retrieved and their main results and conclusions are mentioned briefly. It is quite important to form a multidisciplinary taskforce on GT with the aim of designing and implementing a comprehensive, collaborative, and a strategic work plan, prioritizing and assessing the most relevant diseases, so as to decrease human morbimortality due to exposure to environmental chemicals and stressors.

Cinnamomum cassia on Arterial Stiffness and Endothelial Dysfunction in Type 2 Diabetes Mellitus: Outcomes of a Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

Cinnamomum cassia is a medicinal plant whose use has demonstrated benefits on body weight, blood pressure, glucose, and lipids. This study aimed to evaluate the effect of C. cassia on arterial stiffness and endothelial dysfunction (ED) in patients with type 2 diabetes mellitus (T2DM). A randomized, double-blind, placebo-controlled clinical trial was carried out in 18 subjects aged 40-65 years, with a diagnosis of T2DM of one year or less since diagnosis and treated with Metformin 850 mg daily. Patients were randomly assigned to receive either C. cassia or a placebo in 1000 mg capsules, thrice a day, before each meal for 12 weeks. At baseline and after 12 weeks of intervention, brachial-ankle pulse wave velocity and Flow Mediated Dilation were measured, as well as body weight, body mass index (BMI), blood pressure (BP), fasting glucose (FG), glycated hemoglobin A1c (HbA1c), total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, and very low density lipoprotein cholesterol, respectively, triglycerides, creatinine, and transaminases. The Mann-Whitney U test for differences between groups and the Wilcoxon signed-rank test for intragroup differences were used, and a P ≤ .05 was considered statistically significant. After C. cassia administration, statistically significant reductions in body weight (81.4 ± 10.4 kg vs. 79.9 ± 9.0 kg, P = .037), BMI (30.6 ± 4.2 kg/m2 vs. 30.1 ± 4.2 kg/m2, P = .018), and HbA1c (53 ± 5.4 mmol/mol vs. 45 ± 2.1 mmol/mol, P = .036) were observed. No changes statistically significant on arterial stiffness, ED, FG, BP, and lipids were observed. C. cassia administration decreases body weight, BMI, and HbA1c without statistically significant changes on arterial stiffness, ED, FG, BP, and lipids. CTR Number: NCT04259606.

Percentage of change and increment of the glucose level after a normal oral tolerance curve between 24 and 28 weeks of pregnancy.

AIM: To determine the percentage of change and increment in glucose levels after a normal oral glucose tolerance test between 24 and 28 weeks of pregnancy. METHODS: We studied 3510 pregnant women who attended their obstetric delivery at a tertiary care hospital in Guadalajara, Mexico in 2018, according to characteristics and risk 1647 (47%) patients were screened for diabetes diagnosis using the oral glucose tolerance test, 501 patients reported normal values between their 24th and 28th week of pregnancy, only 400 patients had their fasting glucose level measured on the same day of their obstetric delivery, to be compared. RESULTS: Average age was 30 years, with an average of 25.3 weeks of pregnancy. The fasting serum glucose levels taken after 28 weeks of pregnancy and before the obstetrical delivery showed an increase of 1.1 mmol/L in women who develop gestational diabetes mellitus, in contrast to women who did not develop gestational diabetes mellitus after 28 weeks their blood glucose only increased on average 0.4 mmol/L. The incidence of gestational diabetes mellitus in the study population during 2018 was 32.7%. Patients who developed gestational diabetes mellitus after a normal oral glucose tolerance test had greater body mass index before the pregnancy and newborns had a higher weight than babies born to mothers without gestational diabetes mellitus. CONCLUSION: Changes in glucose levels after the oral tolerance test of normal glucose require strict monitoring, in that it was demonstrated that 3% of patients developed gestational diabetes mellitus after week 28 of gestation.

Association of Netrin 1 with hsCRP in Subjects with Obesity and Recent Diagnosis of Type 2 Diabetes.

Netrin 1 (Ntn1) is a cell migration protein with an anti-inflammatory effect, which may play a key role in the pathological development of type 2 diabetes (T2D). In this study, we evaluate the relationships between the serum concentrations of Ntn1, glucose, and high-sensitivity C-reactive Protein (hsCRP). We carried out a cross-sectional study including 90 individuals divided into three groups (n = 30): healthy subjects, individuals with obesity without glucose alterations, and individuals with newly diagnosed T2D. Serum concentrations of Ntn1 and hs-CRP were determined by enzyme-linked immunosorbent assay (ELISA). The serum concentration of Ntn1 was higher in individuals with newly diagnosed T2D (0.33 ± 0.22 ng/mL), in comparison to healthy subjects and individuals with obesity (0.13 ± 0.06 and 0.15 ± 0.07 ng/mL, respectively). In addition, we observed a positive association between the levels of Ntn1 and hsCRP (rho = 0.443; p < 0.001) as well as with serum glucose (rho = −0.110; p = 0.05). The serum concentration of Ntn1 was higher in individuals with T2D, in comparison with the other groups in this study, and presented a positive correlation with hsCRP. Therefore, Ntn1 can be considered a promising risk biomarker and a potential therapeutic target for T2D.

Morbid obesity is associated with mortality and acute kidney injury in hospitalized patients with COVID-19.

BACKGROUND & AIMS: Mexico has one of the highest mortality rates by COVID-19 worldwide. This may be partially explained by the high prevalence of overweight/obesity found in general population; however, there is limited information in this regard. Furthermore, acute kidney injury (AKI) and need for renal replacement therapy (RRT) associated to obesity in patients with COVID-19 are still topics of discussion. AIM: To explore the association of obesity, particularly morbid obesity, with mortality and kidney outcomes in a Mexican population of hospitalized patients with COVID-19. METHODS: Retrospective cohort study of 773 patients with COVID-19 hospitalized in a tertiary-care teaching hospital in the Mexican state of Jalisco. Baseline body mass index was classified as: normal weight (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), obesity (30-39.9 kg/m2), and morbid obesity (≥40 kg/m2). AKI was diagnosed according to KDIGO clinical practice guidelines. RESULTS: At baseline, 35% of patients had overweight, 39% obesity and 8% morbid obesity. Patients with obesity were younger, more frequently women and with hypertension than normal weight and overweight patients. Frequency of complications in the univariate analysis were not significantly associated to obesity, however in the multivariate analysis (after adjusting for baseline clinical and biochemical differences), morbid obesity was significantly associated to an increased risk of AKI [OR = 2.70 (1.01-7.26), p = 0.05], RRT [OR = 14.4 (1.46-42), p = 0.02], and mortality [OR = 3.54 (1.46-8.55), p = 0.005]. CONCLUSIONS: Almost half of the sample had obesity and morbid obesity. Morbid obesity was significantly associated to an increased risk of AKI, RRT and mortality in hospitalized patients with COVID-19.

Risk factors for mortality of adult patients with COVID-19 hospitalised in an emerging country: a cohort study.

OBJECTIVE: To describe mortality of in-hospital patients with COVID-19 and compare risk factors between survivors and non-survivors. DESIGN: Prospective cohort of adult inpatients. SETTING: Tertiary healthcare teaching hospital in Guadalajara, Mexico. PARTICIPANTS: All patients with confirmed COVID-19 hospitalised from 25 March to 7 September 2020 were included. End of study: 7 November 2020. PRIMARY OUTCOME MEASURES: Patient survival analysed by the Kaplan-Meier method and comparison of factors by the log-rank test. Mortality risk factors analysed by multivariate Cox's proportional-hazard model. RESULTS: One thousand ten patients included: 386 (38%) died, 618 (61%) alive at discharge and six (0.6%) remained hospitalised. There was predominance of men (63%) and high frequency of overweight-obesity (71%); hypertension (54%); diabetes (40%); and lung (9%), cardiovascular (8%) and kidney diseases (11%); all of them significantly more frequent in non-survivors. Overweight-obesity was not different between groups, but severity of disease (Manchester Triage System and quick Sequential Organ Failure Assessment) was significantly worse in non-survivors, who were also significantly older (65 vs 45 years, respectively) and had haematological, biochemical, coagulation and inflammatory biomarkers more altered than survivors. Mortality predictors were invasive mechanical ventilation (IMV; OR 3.31, p<0.0001), admission to intensive care unit (ICU; OR 2.18, p<0.0001), age (OR 1.02, p<0.0001), Manchester Triage System (urgent OR 1.44, p=0.02; immediate/very urgent OR 2.02, p=0.004), baseline C reactive protein (CRP; OR 1.002, p=0.009) and antecedent of kidney disease (OR 1.58, p=0.04) CONCLUSIONS: Mortality in hospitalised patients with COVID-19 in this emerging country centre seemed to be higher than in developed countries. Patients displayed a high frequency of risk factors for poor outcome, but the need for IMV, ICU admission, older age, more severe disease at admission, antecedent of kidney disease and higher CRP levels significantly predicted mortality.

Association between the polymorphism of three genes involved in the methylation and efflux of arsenic (As3MT, MRP1, and P-gp) with lung cancer in a Mexican cohort.

Lung cancer is the most common neoplasm and the primary cause-related mortality in developed and in most of nondeveloped countries. Epidemiological studies have demonstrated that even at low arsenic doses, the lungs are one of the main target organs and that chronic arsenic exposure has been associated with an increase in lung cancer development. Among the risk factors for cancer, arsenic methylation efficiency (As3MT) and the clearance of arsenic from cells by two members of the ATP-binding cassette (ABC) transporter family (multidrug resistance protein 1 [MRP1] and P-glycoprotein [P-gp]) play an important role in processing of arsenic and decreasing its intracellular levels. This study aimed to evaluate the association between chronic exposure to arsenic with polymorphism of three proteins involved in arsenic metabolism and efflux of the metalloid in subjects with lung cancer. Polymorphism in As3MT, MRP1, and P-gp modified the arsenic metabolism increasing significantly the AsV urinary levels. A significant association between MRP1 polymorphisms with an increase in the risk for cancer was found. The high inorganic arsenic urinary levels registered in the studied subjects suggest a reduction in the efficiency of As3MT, MRP1, and P-gp firstly because of gene polymorphisms and secondarily because of high internal inorganic arsenic levels. MRP1 polymorphism was associated with a twofold increase in the risk of lung cancer.

Administration of Herbarium Mixture (Guazuma ulmifolia/Tecoma stans) on Metabolic Profile in Type 2 Diabetes Mellitus Patients: A Randomized, Double-Blind, Placebo-Controlled Trial.

The use of herbarium mixture has been empirical, and the properties are not yet known. The aim of this study was to evaluate the effect of oral administration of herbarium mixture (Guazuma ulmifolia [G. ulmifolia]/Tecoma stans [T. stans]) on metabolic profile in patients with type 2 diabetes mellitus (T2DM). A randomized, double-blind, placebo-controlled, clinical trial was carried out in 40 patients with T2DM. They were between 40 and 65 years of age, with body mass index (BMI) between 25.0 and 34.9 kg/m2 and HbA1c >7.0%. BMI, waist circumference, fasting glucose, HbA1c, lipids, kidney, and liver function were measured. The patients were randomly assigned to receive the herbarium mixture (G. ulmifolia/T. stans) 400 mg before each meal, or placebo for 90 days. Herbarium mixture group showed decreased waist circumference (99 ± 14 vs. 98 ± 15 cm; P = .019), fasting glucose (12.0 ± 5.7 vs. 10.3 ± 5.1 mM; P = .019), and HbA1c (9.9% ± 2.7% vs. 8.9% ± 2.5%, P = .002). In conclusion, the administration of herbarium mixture (G. ulmifolia/T. stans) improved the glycemic profile in patients with T2DM. ClinicalTrial registration: NCT03313856 ClinicalTrials.gov.

Efficacy of clindamycin compared with amoxicillin-metronidazole after a 7-day regimen in the treatment of periodontitis in patients with diabetes: a randomized clinical trial.

OBJECTIVE: To determine the efficacy of clindamycin compared with amoxicillin-metronidazole after a 7-day regimen during nonsurgical treatment of periodontitis in patients with type 2 diabetes mellitus. RESEARCH DESIGN AND METHODS: In this double-blind, randomized clinical trial, a total of 42 patients with chronic periodontitis and type 2 diabetes were included. Patients were randomly assigned to treatment with either clindamycin or amoxicillin-metronidazole three times a day during 7 days. Clinical determinations (probing depth, bleeding on probe, and plaque index) were performed to determine the extent and severity of periodontitis before and after the pharmacological treatment. RESULTS: After 7 days of administration of clindamycin or amoxicillin-metronidazole, no differences were observed between the clinical determinations, probing depth (0.44 vs 0.50 mm, p=0.624), plaque index (17.62 vs 15.88%, p=0.910), and bleeding on probing (16.12 vs 22.17%, p=0.163), respectively. There were no adverse events in either group. CONCLUSION: The administration during 7 days of clindamycin or amoxicillin/metronidazole showed the same efficacy for the reduction of probing depth, plaque index, and bleeding on probing in patients with periodontitis and type 2 diabetes.

Fasting triglycerides and glucose index: a useful screening test for assessing insulin resistance in patients diagnosed with rheumatoid arthritis and systemic lupus erythematosus.

BACKGROUND: Insulin resistance (IR) is frequently observed in patients with rheumatoid arthritis (RA) or systemic lupus erythematosus (SLE). In clinical practice, IR assessment is limited to a low proportion of patients due to cost and equipment and technical expertise requirements. The surrogate index of triglycerides and glucose (TyG index) has been validated in non-rheumatic populations, showing adequate sensitivity and specificity for IR, although this index has not yet been used in connective tissue disorders. The aim of this study was to evaluate the frequency of insulin resistance (IR) using the validated surrogate index of triglycerides and glucose (TyG index) and to explore factors associated with IR in Mexican women with RA or SLE. METHODS: Ninety-five female RA and 57 SLE patients were included in a cross-sectional study. Clinical and epidemiological variables were evaluated. IR was assessed using the TyG index with a cutoff value of > 4.68. Logistic regression analysis was performed to identify factors associated with IR excluding confounders. RESULTS: IR frequency in the entire sample was 50%, higher than the 10% observed in non-rheumatic controls (p < 0.001). The frequency of IR was similar in SLE (49.1%) and RA (50.5%, p = 0.8) patients. IR was associated with a longer duration of hypertension and higher total cholesterol and low density lipoprotein cholesterol levels. Based on multivariate analysis, the duration of hypertension (OR: 1.06; 95% CI 1.002-1.12, p = 0.04), waist circumference (OR: 1.04; 95% CI 1.01-1.08, p = 0.007), uric acid levels (OR: 1.46; 95% CI 1.08-1.97, p = 0.01), RA (OR: 4.87; 95% CI 1.31-18.78, p = 0.01) and SLE (OR: 4.22; 95% CI 1.06-16.74, p = 0.04) were the main risk factors for IR. CONCLUSIONS: This study shows that the TyG index is a useful screening test for IR in RA and SLE patients. Future longitudinal studies should be performed with the aim of identifying the predictive value of TyG index results for identifying complications linked to IR.

Associated factors with sarcopenia among Mexican elderly: 2012 National Health and Nutrition Survey / Factores asociados a sarcopenia en adultos mayores mexicanos: Encuesta Nacional de Salud y Nutrición 2012

Background: Sarcopenia involves the loss of skeletal muscle mass and age-related functionality; it diminishes physical independence, health and quality of life. In 2016 it was added to the International Classification of Diseases (ICD-10). Information about the frequency of sarcopenia among Mexican older adults is scarce. The objective was to analyze associated factors with sarcopenia in Mexican older adults through the 2012 National Health and Nutrition Survey data. Methods: Cross-sectional study which included subjects of 60 years of age or more with simultaneous information on health and anthropometry questionnaires from the 2012 National Health and Nutrition Survey. Sarcopenia was diagnosed through a gait speed test and calf circumference. It was assessed the prevalence of sarcopenia and its association with sociodemographic characteristics and variables related to health, tobacco use and alcohol consumption. The analysis was performed with SPSS v. 16. Results: We analyzed a sample of 5046 older adults who represented 7 439 686 older adults nationwide. Among subjects 53.9% (n = 2718) were women (mean age 69.92 ± 7.56 years) and 46.1% (n = 2328), men (mean age 70.43 ± 7.73 years). Prevalence of presarcopenia was 8.70% and sarcopenia, 13.30%. Conclusion: Sarcopenia was more prevalent in women and it increases with age. It has a significant relationship with falls, cognitive impairment, central obesity and high levels of marginalization.

Introducción: la sarcopenia es la pérdida de masa muscular esquelética y de funcionalidad relativa a la edad; disminuye la independencia funcional, la salud y la calidad de vida. En 2016 se integró a la Clasificación Internacional de Enfermedades. La información epidemiológica de la sarcopenia entre adultos mayores mexicanos es escasa. El objetivo fue analizar los factores asociados a la presencia de sarcopenia en adultos mayores mexicanos, mediante datos de la Encuesta Nacional de Salud y Nutrición 2012. Métodos: estudio transversal en el que participaron sujetos de 60 años o más con información simultánea en cuestionarios de la Encuesta Nacional de Salud y Nutrición 2012. La sarcopenia se determinó por la velocidad de la marcha y la circunferencia de pantorrilla. Se evaluó la prevalencia de sarcopenia y su asociación con características sociodemográficas y de salud, tabaquismo y consumo de alcohol. El análisis se realizó con el programa de IBM SPSS, versión 16. Resultados: se analizó una muestra de 5046 adultos mayores, que representaban a 7 439 686 adultos mayores a nivel nacional. Entre los sujetos el 53.9% (n = 2718) fueron mujeres (edad promedio 69.92 ± 7.56 años) y 46.1% (n = 2328) fueron hombres (edad promedio 70.43 ± 7.73 años). La prevalencia de presarcopenia fue 8.70% y la de sarcopenia 13.30%. Conclusión: la sarcopenia es prevalente en mujeres e incrementa con la edad, tiene asociación con caídas, deterioro cognitivo, obesidad abdominal y marginación alta.

Exposición a Bisfenol A (BPA) en mujeres embarazadas y su relación con la obesidad en sus hijos: Revisión Sistemática / Pregnant Women's Exposure to Bisphenol A (BPA) and its Relation to their Children's Obesity: A systematic Review / Exposição ao bisfenol a (BPA) em mulheres engravidadas e a sua relação com a obesidade em seus filhos: uma revisão sistemática

Resumen Introducción: El bisfenol A (BPA) es un contaminante químico no persistente que altera el funcionamiento normal del sistema endocrino. Se sugiere que la exposición prenatal a BPA se asocia con la obesidad en la descendencia. Objetivo: Revisar la literatura sobre la exposición al BPA en mujeres embarazadas y su relación con la obesidad en sus hijos. Metodología: Revisión sistemática de acuerdo a la guía PRISMA, donde se realizaron búsquedas en las bases de datos Pubmed, ScienceDirect, Clinical Key, Medline, Ebsco y Scielo y el motor de búsqueda Google Scholar hasta 30 de abril de 2017 por dos investigadores independientes que utilizaron iguales términos de búsqueda. Se incluyeron estudios prospectivos de cohorte realizados que midieron el BPA en la orina materna. Resultados: Se incluyeron 5 estudios con tamaños de muestra que varían entre 297 y 757 binomios madre e hijo, se encontró asociación positiva entre la exposición prenatal a BPA con la circunferencia de cintura en niños de cuatro años β: 0.28 (IC95%:0.01 a 0.57) y el índice de masa grasa β: 0.31 (IC95%: 0.01 a 0.60) en dos de los estudios. Además, se observaron asociaciones positivas y/o negativas no significativas con índice de masa corporal y su puntaje Z, porcentaje de grasa, sobrepeso/obesidad, peso y talla al nacer, porcentaje de masa grasa. Conclusión: Los resultados del cuerpo existente de estudios epidemiológicos de cohorte, limita las afirmaciones sobre un vínculo causal entre la exposición prenatal BPA y la obesidad postnatal.

Abstract Introduction: Bisphenol A (BPA) is a non-persistent chemical pollutant which alters the normal functioning of the endocrine system. It is suggested that prenatal exposure is related to descendant obesity. Objective: Review literature on pregnant women's exposure to BPA and the relation to their children's obesity. Methodology: Systematic review in accordance with PRISMA guidelines. Searches were conducted on databases including Pubmed, ScienceDirect, Clinical Key, Medline, Ebsco and Scielo and Google Scholar search engine until April 30, 2017 by two independent researchers that used the same search terms. Prospective cohort conducted studies were included because they measured BPA in maternal urine. Results: Five studies were included with sample sizes ranging from 297 to 757 mother-child binomials. The review found a positive association between prenatal BPA exposure with 4-year-old children's waist circumference β: 0.28 (95% CI :0.01 to 0.57) and the fat mass index β: 0.31 (95%CI: 0.01 to 0.60) in two of the studies. non-significant positive and/or negative associations where observed with body mass index z-scores, overweight/ obesity, weight and size at birth, body mass percentage. Conclusion: The results of cohort epidemiological studies constrain statements regarding a causal link between prenatal BPA exposure and postnatal obesity.

Resumo Introdução: O bisfenol A (BPA) é um contaminante químico não persistente que altera o funcionamento normal do sistema endócrino. Se sugere que a exposição pré-natal se associa com a obesidade na descendência. Objetivo: Revisar a literatura sobre a exposição ao BPA em mulheres engravidadas e a sua relação com a obesidade em seus filhos. Metodologia: Revisão sistemática de acordo com a guia PRISMA. Se realizaram pesquisas nas bases de dados Pubmed, ScienceDirect, Clinical Key, Medline, Ebsco e Scielo e o motor de pesquisa Google Scholar até o 30 de Abril de 2017 por dois investigadores independentes que utilizaram os mesmos termos de busca. Se incluíram estudos prospectivos de coorte realizados que calcularam o BPA na urina materna. Resultados: Se incluíram 5 estudos com tamanhos de amostra entre 297 e 757 binômios mãe e filho, se encontrou associação positiva entre a exposição pré-natal a BPA com a circunferência de cintura em meninos de quatro anos β: 0.28 (IC95%:0.01 a 0.57) e o índice de massa de gordura β: 0.31 (IC95%: 0.01 a 0.60) em dois dos estudos. Se enxergaram associações positivas e/ou negativas não significativas com índice de massa corporal e a sua pontuação Z, porcentagem de gordura, sobrepeso/obesidade, peso e dimensão ao nascer, porcentagem de massa de gordura. Conclusão: Os resultados de estudos epidemiológicos de coorte, limita as afirmações sobre um vínculo causal entre a exposição pré-natal BPA e a obesidade pós-natal.

Insulin resistance in adult primary care patients with a surrogate index, Guadalajara, Mexico, 2012.

INTRODUCTION: Insulin resistance (IR) is a key molecular disorder related with diabetes mellitus, obesity, and cardiovascular disease. The objective of this study was to determine IR in adult primary care patients using the triglyceride/glucose (TyG) index [(Ln TG (mg/dL) × FG (mg/dL))/2]. METHODS: We conducted a cross-sectional secondary analysis and identified IR subjects according to the TyG index. RESULTS: There were 1500 patients included. Significant differences were found between the IR group versus the insulin-sensitive group, respectively: age (in years), 46.4 ± 9.34 versus 40.24 ± 11.27 (P < 0.001); fasting glucose (mg/dL), 99.87 ± 11.95 versus 84.62 ± 6.59 (P < 0.001); total cholesterol (mg/dL), 203.21 ± 37.38 versus 173.91 ± 33.99 (P < 0.001); triglycerides (mg/dL), 226.40 ± 96.66 versus 111.27 ± 23.44 (P < 0.001); uric acid (mg/dL), 6.09 ± 1.59 versus 4.77 ± 1.40 (P < 0.001); and TyG index, 4.96 ± 0.21 versus 4.48 ± 0.13 (P < 0.001). The cutoff of the TyG index for IR was 4.68 or greater. CONCLUSIONS: The TyG index allows for early diagnosis of IR in primary health care.

Potentially estrogenic polychlorinated biphenyls congeners serum levels and its relation with lung cancer.

Lung cancer is the most common cancer in the world. The main cause of lung cancer is cigarette smoke; however, other important genetic and environmental risk factors play a significant role in the development of lung cancer. Among these factors, occupational and accidental exposure to polychlorinated biphenyls (PCBs) has been associated with an increased risk in lung cancer, suggesting that PCBs could be potent carcinogens. The aim of the present study was to investigate the association between PCB exposure levels, CYP1A1 polymorphisms and the risk of lung cancer. This study enrolled newly diagnosed lung cancer patients. Environmental and occupational information related to the patients studied was collected. Blood samples were taken for the measurement of serum levels of 20 PCB congeners and for CYP1A1 polymorphism analysis. The serum levels of two PCB congeners with potential estrogenic activity were higher in lung cancer patients. The risk of lung cancer was found to correlate with age, gender, smoking history and with agricultural workers, as well as with congener 18. No differences were found in the frequency of CYP1A1 polymorphisms. Furthermore, we did not find a correlation between CYP1A1 polymorphisms and PCB serum levels. The high levels of PCB with estrogenic activity found in our cases, could promote lung cancer inducing cell proliferation in non-neoplastic and neoplastic lung cells via ERß; inducing the formation of DNA adducts, producing oxidative stress with the subsequent DNA damage and increasing the endogenous catechol levels by catechol-O-methyl transferase (COMT) inhibition.

Serum levels of polychlorinated biphenyls in Mexican women and breast cancer risk.

The most prevalent female cancer across the world is breast cancer. Current established breast cancer risk factors explain only a fraction of the breast cancer cases diagnosed, and for this reason, other environmental factors have been studied. Exposure to organochlorine compounds has been linked to an increased incidence of breast cancer, although not all data have been consistent. This study was designed to evaluate the relation between polychlorinated biphenyls (PCB) exposure and breast cancer risk in Mexican women. We recruited 140 women from the General Hospital. The cases were 70 newly diagnosed women. We collected environmental and reproductive information by questionnaire. Blood samples were taken for measurement of serum levels of 20 PCB congeners. Risk of breast cancer was found to be positively associated with heavy congeners, age, postmenopausal status, family history of breast cancer and living close to an industrial facility. When PCB were grouped by structure-activity relationships, the risk of breast cancer was positively associated with groups 2b (odds ratio, OR = 1.90, 95% confidence interval, CI, 1.25-2.88), 3 (OR = 1.81, 95% CI 1.08-3.04) and group 4 (OR = 1.57, 95% CI 1.20-2.07). Among postmenopausal women, PCB levels from groups 1a, 2b, and 4 and total PCB were higher in cases, and an association between risk of breast cancer with groups 1a (OR = 7.59, 95% CI 1.1-51.4), 2b (OR = 3.7, 95% CI 1.2-11.2) and 4 (OR = 1.8, 95% CI 1.1-3.1) was found in this group of women. This study showed an association between heavy and potentially estrogenic PCB congeners and breast cancer risk.

Chitosan improves insulin sensitivity as determined by the euglycemic-hyperinsulinemic clamp technique in obese subjects.

In accordance with obesity is associated with insulin resistance and dyslipidemia and chitosan decrease weight and lipids, but its effect on insulin sensitivity is unknown. Our hypothesis for the research was that chitosan improves insulin sensitivity estimated with the euglycemic-hyperinsulinemic clamp technique in obesity. We undertook this study with the objective to determine the effect of chitosan on insulin sensitivity using the euglycemic-hyperinsulinemic clamp technique in obese patients during a 3-month period. A randomized, double-blind clinical trial was carried out in 12 obese adults without diabetes mellitus. During a 3-month period, 6 patients received chitosan (750 mg, 3 times per day) 30 minutes before meals, and the other 6 subjects received placebo. Serum glucose, total cholesterol, high-density lipoprotein cholesterol, and triglycerides (TG) were measured. Insulin sensitivity was estimated with the euglycemic-hyperinsulinemic clamp technique before and after the intervention. Insulin sensitivity increased significantly with the administration of chitosan (2.4 +/- 1.4 vs 3.6 +/- 1.4 mg kg(-1) min(-1); P = .043). In addition, there was a decrease in weight (90.7 +/- 14.2 vs 84.7 +/- 13.7 kg; P = .027), body mass index (34.3 +/- 2.7 vs 31.6 +/- 2.2 kg/m(2); P = .028), waist circumference (106 +/- 12 vs 99 +/- 9 cm; P = .028) and TG (2.4 +/- 0.9 vs 1.6 +/- 0.9 mmol/L; P = .028) in the chitosan group. In conclusion, 3-month administration of chitosan increased insulin sensitivity in obese patients and demonstrated a decrease in weight, body mass index, waist circumference, and TG.

The product of triglycerides and glucose, a simple measure of insulin sensitivity. Comparison with the euglycemic-hyperinsulinemic clamp.

CONTEXT: To meet the worldwide challenge of emerging diabetes, accessible and inexpensive tests to identify insulin resistance are needed. OBJECTIVE: To evaluate the sensitivity and specificity of the product of fasting, we compared the triglycerides and glucose (TyG) index, a simple measure of insulin resistance, with the euglycemic-hyperinsulinemic clamp test. DESIGN AND SETTING: We conducted a cross-sectional study of the general population and outpatients of the Internal Medicine Department at the Medical Unit of High Specialty of the Specialty Hospital at the West National Medical Center in Guadalajara, Mexico. PATIENTS: Eleven nonobese healthy subjects, 34 obese normal glucose tolerance individuals, 22 subjects with prediabetes, and 32 diabetic patients participated in the study. INTERVENTION: We performed a euglycemic-hyperinsulinemic clamp test. MAIN OUTCOME MEASURES: Sensitivity and specificity of the TyG index [Ln(fasting triglycerides) (mg/dl) x fasting glucose (mg/dl)/2] were measured, as well as the area under the curve of the receiver operating characteristic scatter plot and the correlation between the TyG index and the total glucose metabolism (M) rates. RESULTS: Pearson's correlation coefficient between the TyG index and M rates was -0.681 (P < 0.005). Correlation between the TyG index and M rates was similar between men (-0.740) and women (-0.730), nonobese (-0.705) and obese (-0.710), and nondiabetic (-0.670) and diabetic (-0.690) individuals. The best value of the TyG index for diagnosis of insulin resistance was 4.68, which showed the highest sensitivity (96.5%) and specificity (85.0%; area under the curve + 0.858). CONCLUSIONS: The TyG index has high sensitivity and specificity, suggesting that it could be useful for identification of subjects with decreased insulin sensitivity.

Effect of oral L-carnitine administration on insulin sensitivity and lipid profile in type 2 diabetes mellitus patients.

AIM: It was the aim of this study to evaluate the effect of oral L-carnitine administration on insulin sensitivity and lipid profile in subjects with type 2 diabetes mellitus. SUBJECTS AND METHODS: A randomized, double-blind, placebo-controlled clinical trial was carried out in 12 subjects with type 2 diabetes. Six subjects received L-carnitine 1 g orally 3 times a day before meals for a period of 4 weeks. Six other individuals took a placebo for the same period of time, as the control group. Before and after the intervention, insulin sensitivity and the lipid profile were estimated. To assess insulin sensitivity, the euglycemic-hyperinsulinemic clamp technique was performed. Wilcoxon's signed rank and the Mann-Whitney U test were used for the statistical analyses. RESULTS: There were no significant differences in basal clinical characteristics between the 2 groups. Insulin sensitivity and the basal lipid profile were similar. There were no significant changes in either group after the intervention in insulin sensitivity (3.2 +/- 1.2 vs. 4.5 +/- 1.7 mg/kg/min, p = 0.115, and 3.5 +/- 0.6 vs. 3.5 +/- 0.4 mg/kg/min, p = 0.917, for the placebo and L-carnitine groups, respectively) and in lipid profile. CONCLUSION: L-Carnitine orally administered for a period of 4 weeks did not modify insulin sensitivity or the lipid profile.