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Introduction: The intricate relationship between obesity and chronic kidney disease (CKD) progression underscores a significant public health challenge. Obesity is strongly linked to the onset of several health conditions, including arterial hypertension (AHTN), metabolic syndrome, diabetes, dyslipidemia, and hyperuricemia. Understanding the connection between CKD and obesity is crucial for addressing their complex interplay in public health strategies., Objective: This research aimed to determine the prevalence of CKD in a population with high obesity rates and evaluate the associated metabolic risk factors., Material and Methods: In this cross-sectional study conducted from January 2017 to December 2019 we included 3,901 participants of both sexes aged ≥20 years who were selected from primary healthcare medical units of the Mexican Social Security Institute (IMSS) in Michoacan, Mexico. We measured the participants' weight, height, systolic and diastolic blood pressure, glucose, creatinine, total cholesterol, triglycerides, HDL-c, LDL-c, and uric acid. We estimated the glomerular filtration rate using the Collaborative Chronic Kidney Disease Epidemiology (CKD-EPI) equation., Results: Among the population studied, 50.6% were women and 49.4% were men, with a mean age of 49 years (range: 23-90). The prevalence of CKD was 21.9%. Factors significantly associated with an increased risk of CKD included age ≥60 years (OR = 11.70, 95% CI [9.83-15.93]), overweight (OR = 4.19, 95% CI [2.88-6.11]), obesity (OR = 13.31, 95% CI [11.12-15.93]), abdominal obesity (OR = 9.25, 95% CI [7.13-11.99]), AHTN (OR = 20.63, 95% CI [17.02-25.02]), impaired fasting glucose (IFG) (OR = 2.73, 95% CI [2.31-3.23]), type 2 diabetes (T2D) (OR = 14.30, 95% CI [11.14-18.37]), total cholesterol (TC) ≥200 mg/dL (OR = 6.04, 95% CI [5.11-7.14]), triglycerides (TG) ≥150 mg/dL (OR = 5.63, 95% CI 4.76-6.66), HDL-c <40 mg/dL (OR = 4.458, 95% CI [3.74-5.31]), LDL-c ≥130 mg/dL (OR = 6.06, 95% CI [5.12-7.18]), and serum uric acid levels ≥6 mg/dL in women and ≥7 mg/dL in men (OR = 8.18, 95% CI [6.92-9.68]), ( p  < 0.0001). These factors independently contribute to the development of CKD., Conclusions: This study underscores the intricate relationship between obesity and CKD, revealing a high prevalence of CKD. Obesity, including overweight, abdominal obesity, AHTN, IFG, T2D, dyslipidemia, and hyperuricemia emerged as significant metabolic risk factors for CKD. Early identification of these risk factors is crucial for effective intervention strategies. Public health policies should integrate both pharmacological and non-pharmacological approaches to address obesity-related conditions and prevent kidney damage directly., Competing Interests: Author ALP holds shares of Amphora Health. Authors ALP, JT, and MFRM contributed to the research while employed by Amphora Health. All other authors declare no competing interests., (©2024 Alvarez Paredes et al.)

Objective: We sought to test whether a 2-week Total Worker Health (TWH) training mapped to TWH education competencies could be administered to a Mexican audience of occupational safety and health professionals and could lead to positive changes to knowledge and behaviors., Methods: This study used robust program evaluation methods collected before and after each of the nine training days and at the end of the course., Results: Overall course quality received a mean score of 4.6 (SD = 0.6) and 98.8% of participants agreed that their TWH knowledge increased. All participants intended to make at least one change to their professional practice, most frequently helping companies assess their organizational culture to support health, safety, and well-being., Conclusions: This TWH training was well received and led to positive self-reported increase in knowledge and abilities to influence workers' health, safety, and well-being., Competing Interests: Conflict of interest: The University of Colorado developed a Memorandum of Understanding with the Instituto Mexicano del Seguro Social (IMSS), which funded the development and implementation of the Total Worker Health® training. The IMSS selected the employees who would participate in the training. The IMSS had no role in evaluation data collection, analysis, or interpretation. The corresponding author had full access to all the raw evaluation data and had final responsibility for the decision to submit for publication. No additional conflicts of interest declared from any author., (Copyright © 2024 American College of Occupational and Environmental Medicine.)

Background: The global market share for cigarettes with flavor capsules has grown exponentially over the last decade, particularly in Latin America. When smoking, consumers crush a liquid capsule in the filter that flavors the smoke. Little is known about the chemical constituents of the liquids in capsules or their potential health risks., Methods: Based on consumer data and availability in Mexico and Guatemala, 31 flavor capsule brands were purchased (19 and 12, respectively) in 2020. Since some cigarettes included multiple capsules in a stick (up to 2) or pack (up to 4), the final analytic sample included 50 capsules. We conducted qualitative and quantitative analyses using gas chromatography with mass spectrometry (GC-MS, Agilent Technologies, Inc)., Results: The qualitative analysis detected 296 compounds (range = 9-67 per capsule), and all capsules contained menthol. Among the compounds detected in more than half the sample were limonene, menthone, benzaldehyde, eucalyptol, and triacetin. Traces of nicotine were found in 22% of the capsules. In the quantitative analysis, menthol concentrations were 33 times greater than the next most common compound (limonene). Benzyl alcohol and vanillin were also found in high concentrations. Comparing same-brand varieties across countries showed substantial variability in the concentration of menthol and other compounds., Conclusions: Menthol is an omnipresent constituent in capsule cigarettes, perhaps because of its anesthetizing and reinforcing addictive properties. Other compounds found are toxic, potentially carcinogenic, and may enhance addictiveness. Variance in the presence and concentrations of such compounds highlights the importance of product standards to regulate capsule content., Implications: This study evaluated the chemical content of capsule cigarettes from two Latin American countries that have two of the highest market shares for capsule cigarettes worldwide. Compared to other studies, our assessment included brand varieties from two countries to compare the differences in chemical content by country. Our results yield that menthol is found in all capsules, and that other chemicals found may prolong nicotine exposure and therefore reinforce the addictive properties of cigarettes., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The COVID-19 pandemic presents global health, welfare, and economic concerns. The agricultural workforce has experienced adverse effects, placing the U.S. food supply at risk. Agricultural workers temporarily travel to the United States on H-2A visas to supplement the agricultural workforce. Approximately 300,000 agricultural workers enter the United States with H-2A visas each year; over 90.0% are from Mexico. During February-May 2021, a COVID-19 testing pilot was performed with Clínica Médica Internacional (CMI), a clinic that performs medical examinations for US-bound immigrants, to determine the SARS-CoV-2 infection status of H-2A agricultural workers in Mexico before entry to the US. The CerTest VIASURE Real Time PCR Detection Kit was used. Participants' demographic information, test results, and testing turnaround times were collected. Workers who tested positive for SARS-CoV-2 completed isolation before US entry. During the pilot, 1195 H-2A workers were tested; 15 (1.3%) tested positive. Average reporting time was 31 h after specimen collection. This pilot demonstrated there is interest from H-2A employers and agents in testing the H-2A community before US entry. Testing for SARS-CoV-2 can yield public health benefit, is feasible, and does not delay entry of temporary agricultural workers to the US., (© 2023. The Author(s).)

Mexico was caught unprepared to deal with the current COVID-19 pandemic. One of the most egregious failures was the incapability to provide an additional 10,000 ventilators in order to cope with the excess demand. The Mexican government proposed a program for funding the development of these devices and over 100 designs were submitted but were of below standard quality and performance. Only three designs have been approved up to date.This work analyzes the failures from the point of view of the incapability to design, develop and test locally made ventilator designs, and asks whether the national university system, after a history of 48 years of producing thousands of Biomedical Engineering students in over 60 institutions has become incapable of delivering a design of a medical device of medium complexity.

Aim: Skeletal-related events (SREs) are major bone complications that frequently occur in patients with solid tumors (ST) and bone metastases, and in patients with multiple myeloma (MM). SREs include pathological fracture, spinal cord compression, radiation to bone, and surgery to bone. Limited data are available regarding the burden of SREs in Latin America. We built an economic model to quantify the current and future economic burden of SREs among adults in four Latin American countries: Argentina, Brazil, Colombia, and Mexico., Methods: A comprehensive literature review with a systematic search strategy was conducted to parameterize the economic burden of illness (BOI) model. Economic analyses were conducted using a prevalence-based model. Aggregate SRE costs obtained from country-specific sources were used. We also included patient productivity losses. Costs were expressed in 2020 USD for the total annual burden, annual burden per 1,000 at risk, and projected five-year burden., Results: The estimated total number of SREs was 251,503 in 2020, amounting to a total annual cost of USD 1.4 billion. The total projected five-year cost was USD 6.9 billion. Annual costs were highest in Brazil (USD 779.1 million), followed by Mexico (USD 281.8 million), Argentina (USD 174.6 million), and Colombia (USD 120.1 million). The average financial burden per 1,000 at risk was greatest in Brazil (USD 3.6 million), followed by Mexico (USD 3.4 million), Colombia (USD 2.9 million), and Argentina (USD 2.7 million)., Conclusion: Despite recommendations by medical societies for the use of bone-targeted agents in patients with solid tumors and bone metastasis or with multiple myeloma and bone lesions, a large proportion of patients at risk of experiencing SREs are not treated. Early detection of bone metastases and SREs and the use of the most effective preventative treatments are needed to decrease the clinical and economic burden of SREs in Latin America.

The initial colonization of the Americas remains a highly debated topic 1 , and the exact timing of the first arrivals is unknown. The earliest archaeological record of Mexico-which holds a key geographical position in the Americas-is poorly known and understudied. Historically, the region has remained on the periphery of research focused on the first American populations 2 . However, recent investigations provide reliable evidence of a human presence in the northwest region of Mexico 3,4 , the Chiapas Highlands 5 , Central Mexico 6 and the Caribbean coast 7-9 during the Late Pleistocene and Early Holocene epochs. Here we present results of recent excavations at Chiquihuite Cave-a high-altitude site in central-northern Mexico-that corroborate previous findings in the Americas 10-17 of cultural evidence that dates to the Last Glacial Maximum (26,500-19,000 years ago) 18 , and which push back dates for human dispersal to the region possibly as early as 33,000-31,000 years ago. The site yielded about 1,900 stone artefacts within a 3-m-deep stratified sequence, revealing a previously unknown lithic industry that underwent only minor changes over millennia. More than 50 radiocarbon and luminescence dates provide chronological control, and genetic, palaeoenvironmental and chemical data document the changing environments in which the occupants lived. Our results provide new evidence for the antiquity of humans in the Americas, illustrate the cultural diversity of the earliest dispersal groups (which predate those of the Clovis culture) and open new directions of research.

Here we studied HLA blocks and haplotypes in a group of 218 Lacandon Maya Native American using a high-resolution next generation sequencing (NGS) method. We assessed the genetic diversity of HLA class I and class II in this population, and determined the most probable ancestry of Lacandon Maya HLA class I and class II haplotypes. Importantly, this Native American group showed a high degree of both HLA homozygosity and linkage disequilibrium across the HLA region and also lower class II HLA allelic diversity than most previously reported populations (including other Native American groups). Distinctive alleles present in the Lacandon population include HLA-A*24:14 and HLA-B*40:08. Furthermore, in Lacandons we observed a high frequency of haplotypes containing the allele HLA-DRB1*04:11, a relatively frequent allele in comparison with other neighboring indigenous groups. The specific demographic history of the Lacandon population including inbreeding, as well as pathogen selection, may have elevated the frequencies of a small number of HLA class II alleles and DNA blocks. To assess the possible role of different selective pressures in determining Native American HLA diversity, we evaluated the relationship between genetic diversity at HLA-A, HLA-B and HLA-DRB1 and pathogen richness for a global dataset and for Native American populations alone. In keeping with previous studies of such relationships we included distance from Africa as a covariate. After correction for multiple comparisons we did not find any significant relationship between pathogen diversity and HLA genetic diversity (as measured by polymorphism information content) in either our global dataset or the Native American subset of the dataset. We found the expected negative relationship between genetic diversity and distance from Africa in the global dataset, but no relationship between HLA genetic diversity and distance from Africa when Native American populations were considered alone.

With increased globalization, Latin America is experiencing transitions from traditional lifestyle and dietary practices to those found in higher income countries. Healthy diets, physical activity and optimal body fat can prevent approximately 15% of cancers in low-income and 20% in high-income countries. We discuss links between diet, obesity, physical activity and cancer, emphasizing strategies targeting children to decrease risk of obesity, control obesity-related risk factors, and reduce sedentary lifestyles, as this will have high impact on adult cancer risk. We focus on individual behaviors, economic, cultural and societal changes that may guide future interventions in the Americas., Competing Interests: Declaration of conflict of interests. The authors declare that they have no conflict of interests.

The Great American Biotic Interchange is considered to be a punctuated process, primarily occurring during four major pulses that began approximately 2.5 Ma. Central America and southeastern Mexico have a poor fossil record of this dynamic faunal history due to tropical climates. Exploration of submerged caves in the Yucatán, particularly the natural trap Hoyo Negro, is exposing a rich and remarkably well-preserved late Pleistocene fauna. Radiometric dates on megafauna range from approximately 38 400-12 850 cal BP, and extinct species include the ursid Arctotherium wingei and canid Protocyon troglodytes. Both genera were previously thought to be indigenous to and confined to South America and appear to represent an instance of large placental mammals, descended from North American progenitors, migrating back north across the Panama Isthmus. This discovery expands the distribution of these carnivorans greater than 2000 km outside South America. Their presence along with a diverse sloth assemblage suggests a more complex history of these organisms in Middle America. We suggest that landscape and ecological changes caused by latest Pleistocene glaciation supported an interchange pulse that included A. wingei, P. troglodytes and Homo sapiens.

Background: Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease of unknown etiology. Genetic variation within different major histocompatibility complex (MHC) loci contributes to the susceptibility to IPF. The effect of 70 kDa heat shock proteins (HSP70) gene polymorphisms in the susceptibility to IPF is unknown. The aim of this study was to explore the association between HSP70 polymorphisms and IPF susceptibility in the Mexican population., Methods: Four HSP70 single nucleotide polymorphisms (SNPs) were evaluated using real time PCR assays in 168 IPF patients and 205 controls: +2763 C>T of HSPA1L (rs2075800), +2437 of HSP HSPA1L A>G (rs2227956), +190 of HSPA1A G>C (rs1043618) and +1267 of HSPA1B G>A (rs1061581)., Results: The analysis of the recessive model revealed a significant decrease in the frequency of the genotype HSPA1B AA (rs1061581) in IPF patients (OR = 0.27, 95 % CI = 0.13-0.57, Pc = 0.0003) when compared to controls. Using a multivariate logistic regression analysis in a codominant model the HSPA1B (rs1061581) GA and AA genotypes were associated with a lower risk of IPF compared with GG (OR = 0.22, 95 % CI = 0.07-0.65; p = 0.006 and OR = 0.17, 95 % CI = 0.07-0.41; p = <0.001). Similarly, HSPA1L (rs2227956) AG genotype (OR = 0.34, 95 % CI = 0.12-0.99; p = 0.04) and the dominant model AG + GG genotypes were also associated with a lower risk of IPF (OR = 0.24, 95 % CI = 0.08-0.67; p = 0.007). In contrast, the HSPA1L (rs2075800) TT genotype was associated with susceptibility to IPF (OR = 2.52, 95 % CI = 1.32-4.81; p = 0.005)., Conclusion: Our findings indicate that HSPA1B (rs1061581), HSPA1L (rs2227956) and HSPA1 (rs1043618) polymorphisms are associated with a decreased risk of IPF.

Introduction: Human leukocyte antigen (HLA) polymorphism studies in Systemic Sclerosis (SSc) have yielded variable results. These studies need to consider the genetic admixture of the studied population. Here we used our previously reported definition of genetic admixture of Mexicans using HLA class I and II DNA blocks to map genetic susceptibility to develop SSc and its complications., Methods: We included 159 patients from a cohort of Mexican Mestizo SSc patients. We performed clinical evaluation, obtained SSc-associated antibodies, and determined HLA class I and class II alleles using sequence-based, high-resolution techniques to evaluate the contribution of these genes to SSc susceptibility, their correlation with the clinical and autoantibody profile and the prevalence of Amerindian, Caucasian and African alleles, blocks and haplotypes in this population., Results: Our study revealed that class I block HLA-C*12:03-B*18:01 was important to map susceptibility to diffuse cutaneous (dc) SSc, HLA-C*07:01-B*08:01 block to map the susceptibility role of HLA-B*08:01 to develop SSc, and the C*07:02-B*39:05 and C*07:02-B*39:06 blocks to map the protective role of C*07:02 in SSc. We also confirmed previous associations of HLA-DRB1*11:04 and -DRB1*01 to susceptibility to develop SSc. Importantly, we mapped the protective role of DQB1*03:01 using three Amerindian blocks. We also found a significant association for the presence of anti-Topoisomerase I antibody with HLA-DQB1*04:02, present in an Amerindian block (DRB1*08:02-DQB1*04:02), and we found several alleles associated to internal organ damage. The admixture estimations revealed a lower proportion of the Amerindian genetic component among SSc patients., Conclusion: This is the first report of the diversity of HLA class I and II alleles and haplotypes Mexican patients with SSc. Our findings suggest that HLA class I and class II genes contribute to the protection and susceptibility to develop SSc and its different clinical presentations as well as different autoantibody profiles in Mexicans.

Because of differences in craniofacial morphology and dentition between the earliest American skeletons and modern Native Americans, separate origins have been postulated for them, despite genetic evidence to the contrary. We describe a near-complete human skeleton with an intact cranium and preserved DNA found with extinct fauna in a submerged cave on Mexico's Yucatan Peninsula. This skeleton dates to between 13,000 and 12,000 calendar years ago and has Paleoamerican craniofacial characteristics and a Beringian-derived mitochondrial DNA (mtDNA) haplogroup (D1). Thus, the differences between Paleoamericans and Native Americans probably resulted from in situ evolution rather than separate ancestry., (Copyright © 2014, American Association for the Advancement of Science.)

Background: The control of Mycobacterium tuberculosis (Mtb) infection begins with the recognition of mycobacterial structural components by toll like receptors (TLRs) and other pattern recognition receptors. Our objective was to determine the influence of TLRs polymorphisms in the susceptibility to develop tuberculosis (TB) in Amerindian individuals from a rural area of Oaxaca, Mexico with high TB incidence., Methods: We carried out a case-control association community based study, genotyping 12 polymorphisms of TLR2, TLR4, TLR6 and TLR9 genes in 90 patients with confirmed pulmonary TB and 90 unrelated exposed but asymptomatic household contacts., Results: We found a significant increase in the frequency of the allele A of the TLR9 gene polymorphism rs352139 (A>G) in the group of TB patients (g.f. = 0.522) when compared with controls (g.f. = 0.383), (Pcorr = 0.01, OR = 1.75). Under the recessive model (A/G + A/A vs G/G) this polymorphism was also significantly associated with TB (Pcorr = 0.01, OR= 2.37). The association of the SNP rs352139 was statistically significant after adjustment by age, gender and comorbidities by regression logistic analysis (Dominant model: p value = 0.016, OR = 2.31; Additive model: p value = 0.023, OR = 1.68). The haplotype GAA of TLR9 SNPs was also associated with TB susceptibility (Pcorr = 0.02). Differences in the genotype or allele frequencies of TLR2, TLR4 and TLR6 polymorphisms between TB patients and healthy contacts were not detected., Conclusions: Our study suggests that the allele A of the intronic polymorphism rs352139 on TLR9 gene might contribute to the risk of developing TB in Mexican Amerindians.

Sepsis is a leading cause of death around the world, and 73-83% of all sepsis cases requiring attention in intensive care units are linked to intra-abdominal infection (IAI) or pneumonia. The activation of innate immunity is central to the manifestation of sepsis, and toll-like receptor (TLR) 4 plays an important role in this activation process. The 299G and 399I alleles of TLR4 have been linked with an increased risk of Gram-negative bacteria (GNB) infections and septic shock in some populations. This case-control study evaluated the prevalence of D299G/T399I polymorphisms in Mexican patients with IAI and/or pneumonia and in healthy controls. Genotyping revealed that 1 in 44 patients (2.3%; CI 95%: 0.05-12.0%) and 4 in 126 controls (3.2%; CI 95%: 0.9-7.9%) were heterozygous for both the D299G and T399l polymorphisms (OR: 0.71, CI 95%: 0.01-7.44, p = NS), confirming the co-segregation of these alleles in this population. Furthermore, the patients with a GNB infection and severe sepsis were not carriers of the risk alleles. In summary, this report shows that the frequency of the D299G and T399I polymorphisms in Mexican-Mestizos is lower than anticipated in comparison with other ethnic groups, emphasizing the variable distribution of TLR4 polymorphisms among different populations. Consequently, this study was not able to detect associations between TLR4 polymorphisms and sepsis in this population., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Background: Previous cross-sectional research has suggested single cigarettes could either promote or inhibit consumption. The present study aimed to assess the effects of single cigarette availability and consumption on downstream quit behavior., Methods: We analyzed population-based, longitudinal data from adult smokers who participated in the 2008 and 2010 administrations of the International Tobacco Control Policy Evaluation Survey in Mexico., Results: At baseline, 30% of smokers saw single cigarettes for sale on a daily basis, 17% bought singles at their last purchase, and 7% bought singles daily. Smokers who most frequently purchased singles, both in general and specifically to control their consumption, were no more likely to attempt to quit over the 14 month follow-up period than those who did not purchase singles. Frequency of buying singles to reduce consumption had a non-monotonic association with being quit at followup. The odds of being quit was only statistically significant when comparing those who had not bought singles to reduce consumption with those who had done so on a more irregular basis (AOR = 2.30; 95% CI 1.19, 4.45), whereas those who did so more regularly were no more likely to be quit at followup. Frequency of self-reported urges to smoke upon seeing singles for sale was unassociated with either quit attempts or being quit at followup., Conclusions: These results suggest that the relationship between singles consumption and quit behavior is complex, with no clear evidence that singles either promote or inhibit downstream quit behavior.

Background: Serologic surveillance of Avian Influenza (AI) viruses is carried out by the hemagglutination inhibition (HI) test using reference reagents. This method is recommended by animal health organizations as a standard test to detect antigenic differences (subtypes) between circulating influenza virus, vaccine- and/or reference- strains. However, significant discrepancies between reference antisera and field isolates have been observed during serosurveillance of influenza A viruses in pig and poultry farms. The objective of this study was to examine the effects of influenza virus genetic and antigenic drift on serologic testing using standard HI assays and reference reagents. Low pathogenic AI H5N2 viruses isolated in Mexico between 1994 and 2008 were used for phylogenetic analysis of AI hemagglutinin genes and for serologic testing using antisera produced with year-specific AI virus isolates., Results: Phylogenetic analysis revealed significant divergence between early LPAI H5N2 viruses (1994 - 1998) and more recent virus field isolates (2002 - 2008). Results of the HI test were markedly influenced by the selection of the AI H5N2 virus (year of isolation) used as reference antigen for the assay. These analyses indicate that LPAI H5N2 viruses in Mexico are constantly undergoing genetic drift and that serosurveillance of AI viruses is significantly influenced by the antigen or antisera used for the HI test., Conclusions: Reference viral antigens and/or antisera need to be replaced constantly during surveillance of AI viruses to keep pace with the AI antigenic drift. This strategy should improve the estimation of antigenic differences between circulating AI viruses and the selection of suitable vaccine strains.

This paper describes the work being carried out at Metropolitan Autonomous University (UAM) in Mexico City with regard to the continuous evaluation and updating of the Biomedical Engineering (BME) curriculum. In particular the courses regarded as part of the BME basic branch are reduced and new sets of elective subjects are proposed in order to bring closer the research work at UAM with the subjects in the BME curriculum. Special emphasis is placed on subjects dealing with Health Technology Assessment (HTA) and Health economics, as this branch of the BME discipline is quite promising in Mexico, but there are very few professionals in the field with adequate qualifications.

Objective: Novel, inexpensive solutions are needed for improved management of vector-borne and other diseases in resource-poor environments. Emerging free software providing access to satellite imagery and simple editing tools (e.g. Google Earth) complement existing geographic information system (GIS) software and provide new opportunities for: (i) strengthening overall public health capacity through development of information for city infrastructures; and (ii) display of public health data directly on an image of the physical environment., Methods: We used freely accessible satellite imagery and a set of feature-making tools included in the software (allowing for production of polygons, lines and points) to generate information for city infrastructure and to display disease data in a dengue decision support system (DDSS) framework., Findings: Two cities in Mexico (Chetumal and Merida) were used to demonstrate that a basic representation of city infrastructure useful as a spatial backbone in a DDSS can be rapidly developed at minimal cost. Data layers generated included labelled polygons representing city blocks, lines representing streets, and points showing the locations of schools and health clinics. City blocks were colour-coded to show presence of dengue cases. The data layers were successfully imported in a format known as shapefile into a GIS software., Conclusion: The combination of Google Earth and free GIS software (e.g. HealthMapper, developed by WHO, and SIGEpi, developed by PAHO) has tremendous potential to strengthen overall public health capacity and facilitate decision support system approaches to prevention and control of vector-borne diseases in resource-poor environments.

The earliest stage of drug involvement is being presented with the opportunity to use drugs. During adolescence these opportunities increase. Because of the scarcity of data for the Mexican population, the aim is to estimate the prevalence of drug use opportunities among Mexican adolescents, the prevalence of drug use among those who were presented with the opportunity, and the socio-demographic correlates of both. A multistage probability survey was carried out among 12-17 year olds from Mexico City. Adolescents were administered the adolescent version of the World Mental Health Composite International Diagnostic Interview. The response rate was 71% (n=3005). Descriptive and logistic regression analyses were performed considering the multistage and weighted sample design. Twenty-nine percent has had the opportunity to try illicit drugs; of those presented with an opportunity, 18% has done so. Males, older adolescents, school drop-outs, and those whose parent has had drug problems are more likely to have been exposed to drug use opportunities while more religious adolescents are less likely. Given the chance to try drugs, older adolescents and school drop-outs are more likely to do so and those with high parental monitoring and religiosity are less likely. These results suggest that less substance use among females in Mexico may be due in part to fewer opportunities to use since females were equally likely to use drugs given the opportunity. Given the increase in opportunity among older adolescents, preventive efforts should start by age 12 and with special attention to adolescents who have dropped out of school.

Aims: To estimate the life-time and 12-month prevalence of illicit drug use among Mexican adolescents, the age of onset of first drug use and the socio-demographic correlates., Method: A multi-stage probability survey of adolescents aged 12-17 years residing in the Mexico City Metropolitan Area was carried out in 2005. Adolescents were administered the computer-assisted adolescent version of the World Mental Health Composite International Diagnostic Interview by trained lay interviewers in their homes. The response rate was 71% (n = 3005). Descriptive and logistic regression analyses were performed considering the multi-stage and weighted sample design of the survey., Findings: Of the adolescents, 5.2% have ever tried illicit drugs, 2.9% in the last 12 months. The most frequently used drugs are marijuana, followed by tranquilizers/stimulants. The median age of first use is 14 years. Correlates of life-time drug use are older age, having dropped out of school, parental drug problems, low religiosity and low parental monitoring., Conclusions: While drug use among Mexican adolescents is lower than among adolescents from other developed countries, its increasing prevalence with age and the narrowing male/female ratio calls for firm public health actions, particularly prevention strategies.

Background: The aim was to determine the direct medical costs in patients with partial refractory epilepsy at the Mexican Institute of Social Security (IMSS) in Mexico., Methods: We carried out a multicenter, retrospective-cohort partial-economic evaluation study of partial refractory epilepsy (PRE) diagnosed patients and analyzed patient files from four secondary- and tertiary-level hospitals. PRE patients >12 years of age with two or more antiepileptic drugs and follow-up for at least 1 year were included. The perspective was institutional (IMSS). Only direct healthcare costs were considered, and the timeline was 1 year. Cost techniques were microcosting, average per-service cost, and per-day cost, all costs expressed in U.S. dollars (USD, 2004)., Results: We reviewed 813 files of PRE patients: 133 had a correct diagnosis, and only 72 met study inclusion criteria. Fifty eight percent were females, 64% were <35 years of age, 47% were students, in 73% maximum academic level achieved was high school, and 53% were single. Fifty one percent of cases experienced simple partial seizures and 94% had more than one monthly seizure. Annual healthcare cost of the 72 patients was 190,486 USD, ambulatory healthcare contributing 76% and hospital healthcare with 24%., Conclusions: Annual mean healthcare cost per PRE patient was 2,646 USD; time of disease evolution and severity of the patient's illness did not affect costs significantly.

A report of human footprints preserved in 40,000-year-old volcanic ash near Puebla, Mexico (http://www.royalsoc.ac.uk/exhibit.asp?id=3616&tip=1), was the subject of a press conference that stirred international media attention. If the claims (http://www.mexicanfootprints.co.uk) of Gonzalez et al. are valid, prevailing theories about the timing of human migration into the Americas would need significant revision. Here we show by 40Ar/39Ar dating and corroborating palaeomagnetic data that the basaltic tuff on which the purported footprints are found is 1.30+/-0.03 million years old. We conclude that either hominid migration into the Americas occurred very much earlier than previously believed, or that the features in question were not made by humans on recently erupted ash.

Aims: While alcohol use is thought to be a major risk factor for both fatal and non-fatal injuries, the association of substance use disorders (alcohol use disorders, AUD and substance use disorders, SUD) with occurrence of injury has not received the same attention. To report the association of AUD and SUD, according to diagnostic and statistics manual of mental disorders-IV (DSM-IV) and international classification of diseases 10 (ICD-10) criteria, and the risk of non-fatal injuries., Methods: A case-control study: Cases included 653 injured patients, 18-65-years-old, who attended one emergency department (ED). Controls included 1131 subjects from a representative sample of residents of Mexico City, of the same age group. Information on drug and alcohol use was obtained by interview using the world mental health version of the composite international diagnostic interview (WMH-CIDI)., Results: Among injured patients, the prevalence of substance abuse or dependence within the last 12 months was 12.3% for alcohol and 2.5% for other substances (marijuana, cocaine, tranquilizers, amphetamines, others). Among residents of Mexico City, these prevalences were 1.8 and 0.3%, respectively. Adjusted odds ratios (OR) of injury according to alcohol and substance use were 4.95 (95% confidence interval (CI): 2.87-8.52) for alcohol and 2.58 (0.73-9.17) for other substances. An important level of comorbid alcohol and substance use disorders was also found., Conclusions: Efforts in the ED should be carried out to treat and/or refer patients with alcohol and substance use disorders, and special care should be taken to address comorbid cases.

Tumor necrosis factor alpha (TNF-alpha) gene is located within the class III region of the major histocompatibility complex (MHC) on the short arm of the human sixth chromosome. Two polymorphisms in the promoter region of the TNF-alpha gene (-308 and -238) have been associated with the genetic susceptibility to develop ulcerative colitis in both Caucasian and Asian populations. The aim of this study was to determine the role of TNF-alpha gene polymorphisms and those from the HLA-DRB1 locus in the susceptibility to develop ulcerative colitis (UC). Eighty Mexican mestizo patients suffering from UC and 99 ethnically matched unrelated healthy controls were genotyped for two TNF-alpha polymorphisms located in the promoter region (positions -308, -238) by polymerase chain reaction (PCR) and amplification refractory mutation system (ARMS) as well as high resolution DNA typing for HLA-DRB1 alleles were performed. The frequency of individuals positive for allele 2 of the TNF(-308) polymorphism was significantly higher in UC patients than healthy controls (23.7% versus 3%, pC = 0.00002; OR = 10.1; CI 95% = 2.69-26.8). No statistically significant deviation from normality was found between TNF*A (-238) and UC Mexican patients. Clinical manifestations such as pancolitis, extraintestinal manifestations and colectomy were not associated with any of the TNF promoter region polymorphisms. However, HLA-DRB1*15 was found to be associated with pancolitis and HLA-DRB1*0103 with the need of proctocolectomy. In conclusion, this clinical differential pattern of association distinguished in two neighboring loci within the MHC region suggest an independent role of the TNF locus in the genetic susceptibility to develop UC.

This case study details the difficulties of landscape management, highlighting the challenges inherent in managing natural resources when multiple agencies are involved, when the land users have no incentive for conservation, and when government agencies have too few resources for effective management. Pumping of groundwater from the aquifer of La Costa de Hermosillo in the state of Sonora, Mexico, began in 1945 and developed so quickly that by the late 1950s salinity intrusion from the Gulf of California was occurring in the wells. In the 1970s, the irrigatable land in La Costa peaked at 132,516 ha and the extracted volume of water from the aquifer peaked at around 1.14 billion cubic meters annually. By the 1980s, 105 wells of the total of 498 were contaminated with seawater and, therefore, identified for closure. At present La Costa de Hermosillo still represents 15% of the total harvested land, 16% of the total annual production, and 23% of the gross agricultural production of the state of Sonora. However, there are approximately 80,000 ha of abandoned fields due to salt water intension, lack of water and/or lack of credit available to individual farmers. This unstable situation resulted from the interplay of water management policies and practices, and farm-land policies and practices. While government agencies have been able to enforce better water use for agricultural production, there remains a significant area that requires restoration from its degraded state. For this piece of the ecosystem management puzzle, government agencies have thus far been unable to affect a solution.