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Objective Studies reporting low prevalence of HPV in OSCC with declining age at presentation are increasing. The aim of this study was to determine the prevalence of HPV in a group of OSCC cases and controls in a Mexican population. Methods The matched case-control study included 80 OSCC cases and 320 controls. HPV/ DNA presence was evaluated through PCR amplification using three sets of consensus primers for the L1 gene. A conditional logistic regression analysis was carried out for the matched OSCC cases and controls. Interactions between risk factors and OCSS were tested in the construction process of the models. Results HPV prevalence was 5% in OSCC cases and 2.5% in controls. HPV-detected types were 16, 18 and 56. According to conditional logistics regression model, an association was detected between HR- HPV and OSCC. All HR- HPV-positive OSCC cases corresponded to young patients (<45 years), non-smokers and non-alcohol drinkers. Conclusions The HR- HPV can be a contributing factor to oral carcinogenesis, especially in younger individuals without known risk factors such as tobacco and alcohol. [ABSTRACT FROM AUTHOR]

Introduction Consistent evidence has shown a positive association between air pollution and daily mortality among adults. Less is known about its effect on infant mortality and the modification of this association by socioeconomic status (SES).Objective To assess the association of particulate matter with an aerodynamic diameter of ≤10 μm (PM10) and ozone (O3) on infant mortality and its modification by SES. Methods We evaluated the relationship of 24 h mean PM10 and 1 h daily maximum O3 levels with 12 079 all-cause deaths (3903 respiratory deaths) among 1- to 11-month-old infants residing in the Mexico City Metropolitan Area between January 1997 and December 2005 using a case-crossover approach. The data were analysed using conditional logistic regression models, controlling for weather conditions and day of the week. Results Single-effect models showed, for all-cause mortality, increases of 5.5% (95% CI 1% to 10%) at lag1 and 6.6% (2% to 11.4%) at lag2; cumulative exposure models (0–2 days) showed an increase of 6.3% (0.01% to 32.7%). Respiratory mortality increased marginally at 5.3% (−0.02% to 13.2%) with a 1-day lag and 10% (2.1% to 18%) with a 2-day lag per increase of 38.7 μg/m3 (IQR) in PM10 levels. When data were stratified by SES (low, medium, and high), only infants with low and medium SES presented a significant increase in risk of all-cause mortality and respiratory mortality in relation to PM10. O3 was only significantly related to respiratory mortality in low SES. Conclusion Our results suggest that in the Mexico City Metropolitan Area, infants with lower SES (low to medium) are at higher risk of mortality when exposed to ambient PM10 and O3. [ABSTRACT FROM AUTHOR]

Copyright of Revista Chapingo Serie Horticultura is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It is difficult to develop control strategies for grain mold of sorghum because of the limited information on the epidemiology of grain mold in Mexico. The objectives of this study were to identify the fungi associated with grain mold in Morelos, Mexico, and to explore the relationship among planting dates, disease development, and relative humidity and temperature. Fusarium thapsinum was isolated from 97% of the grains from field samples of infested sorghum grains in Morelos, Mexico. The influence of planting dates on the development of sorghum grain mold was determined at Tlayca, Morelos, Mexico, during the rainy seasons of 1998, 1999, and 2000. Incidence of grain mold varied annually, but disease incidence and severity were highest in 1998. Planting dates from I June to 13 July had the highest incidence of grain mold during the 3 years. Throughout the study, disease severity was generally low, and yield was not affected. The late planting dates in 1999 and 2000 had reduced yields due to terminal drought of the crop. Increase of disease was predicted by mean temperature, but not by mean relative humidity. [ABSTRACT FROM AUTHOR]

Plastic particle occurrence in the digestive tracts of fishes from a tropical estuarine system in the Gulf of California was investigated. A total of 1095 fish were analysed, representing 15 species. In total 1384 particles of plastic debris were recovered from the gastrointestinal tracts of 552 specimens belonging to 13 species, and all consisted of threads, the majority of which were small microplastics (0.23 to 1.89), followed by large microplastics (2.07 to 4.49), and few mesoplastics (5.4 to 19.86). Plastic particles were identified using ATR-FTIR spectroscopy. The mean frequency of occurrence of plastics in the gastrointestinal tracts of fishes from this system was 50.5%, which is higher than frequencies reported in similar systems in other areas. The polymers identified by ATR-FTIR were polyamide (51.2%), polyethylene (36.6%), polypropylene (7.3%), and polyacrylic (4.9%). These results show the first evidence of plastic contamination for estuarine biota in the Gulf of California. • The presence of plastic debris in gastric contents of teleost fish in the Gulf of California is confirmed. • Its frequency of occurrence is much higher than those reported from similar ecosystems. • The most abundant polymer was nylon, indicating a high polution from small scale commercial fishing gear and textiles. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze by Raman and UV–Vis-NIR Spectroscopic techniques, Mexican honey from Apis Mellífera , using representative samples with different botanic origins (unifloral and multifloral) and diverse climates. Using Raman spectroscopy together with principal components analysis, the results obtained represent the possibility to use them for determination of floral origin of honey, independently of the region of sampling. For this, the effect of heat up the honey was analyzed in relation that it was possible to greatly reduce the fluorescence background in Raman spectra, which allowed the visualization of fructose and glucose peaks. Using UV–Vis-NIR, spectroscopy, a characteristic spectrum profile of transmittance was obtained for each honey type. In addition, to have an objective characterization of color, a CIE Yxy and CIE L*a*b* colorimetric register was realized for each honey type. Applying the principal component analysis and their correlation with chromaticity coordinates allowed classifying the honey samples in one plot as: cutoff wavelength, maximum transmittance, tones and lightness. The results show that it is possible to obtain a spectroscopic record of honeys with specific characteristics by reducing the effects of fluorescence. [ABSTRACT FROM AUTHOR]

In this study, we conducted an analysis of health risks faced by residents of Salamanca, Mexico, who were exposed to fine particulate matter with a diameter of 2.5 μm (PM 2.5 ) through inhalation. The characterization and analysis of these particulate matter samples were undertaken. A total of 131 samples were collected from two different sites: 65 from the Red Cross site (RC) and 66 from the Integral Family Development site (DIF) in 2014-2015. These samples were analyzed for a set of chemical components, including metals and ions. Non-cancerous health risk levels associated with PM 2.5 exposure through the human respiratory system, as per the WHO benchmark (assigned a value of 1), revealed notable risk values for two elements: Manganese (Mn) with a range of 1.19-2.12 in the adult population and 1.59-2.84 in the child population, and Nickel (Ni) with a uniform risk value of 1.39 for both evaluated population groups. However, concerns arose regarding potential non-cancerous effects as the cumulative risk levels for various assessed elements showed elevated indices. These ranged from 3.81 to 4.4 in adults and 4.48-5.24 in children. This study provided comprehensive data on composition and its potential impact on human health, offering valuable insights for the implementation of mitigation measures aimed at reducing inhalation-related exposure., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most frequent human enzymopathy, affecting over 400 million people globally. Worldwide, 217 mutations have been reported at the genetic level, and only 19 have been found in Mexico. The objective of this work was to contribute to the knowledge of the function and structure of three single natural variants (G6PD A+, G6PD San Luis Potosi, and G6PD Guadalajara) and a double mutant (G6PD Mount Sinai), each localized in a different region of the three-dimensional (3D) structure. In the functional characterization of the mutants, we observed a decrease in specific activity, protein expression and purification, catalytic efficiency, and substrate affinity in comparison with wild-type (WT) G6PD. Moreover, the analysis of the effect of all mutations on the structural stability showed that its presence increases denaturation and lability with temperature and it is more sensible to trypsin digestion protease and guanidine hydrochloride compared with WT G6PD. This could be explained by accelerated degradation of the variant enzymes due to reduced stability of the protein, as is shown in patients with G6PD deficiency.

Increases in wastewater discharges and the generation of municipal solid wastes have resulted in deleterious effects on the environment, causing eutrophication and pollution of water bodies. It is therefore necessary to investigate sustainable bioremediation alternatives. Wastewater treatment using consortia of microalgae-bacteria is an attractive alternative because it allows the removal and recycling of nutrients, with the additional advantage of biomass production and its subsequent conversion into valuable by-products. The present study aims to integrate wastewater and landfill leachate treatment with the production of microalgal biomass, considering not only its valorization in terms of lipid and carbohydrate content but also the effect of nutrient limitation on biomass formation. The effect of treating a mixture of raw wastewater with different leachate ratios (0%, 7%, 10% and 15%) was investigated using a microalgae-bacteria consortium. Two microalgae (Desmodesmus spp. and Scenedesmus obliquus) were used. Nutrient removal, biomass concentration, carbohydrate, lipid and Fatty Acid Methyl Ester (FAMEs) content and morphological changes were evaluated. Removals of 82% of NH 4 + and 43% of orthophosphate from a wastewater-leachate mixture (containing 167 mg/L NH 4 + and 23 mg/L PO 4 3- ) were achieved. The highest final yield was obtained using Desmodesmus spp. (1.95 ± 0.3 g/L). The microalgae were observed to accumulate high lipid (20%) and carbohydrate (41%) contents under nutrient limiting conditions. The concentration of Polyunsaturated Fatty Acids (PUFAs) also increased. Morphological changes including the disintegration of coenobia were observed. By using a mixture of wastewater-leachate it is possible to remove nutrients, since microalgae tolerate high ammonia concentrations, and simultaneously increase the algal biomass concentration containing precursors to allow biofuel production., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Free-living amoebae of the genus Acanthamoeba are the etiological agents of cutaneous lesions, granulomatous amoebic encephalitis (GAE) and amoebic keratitis (AK), which are chronic infections with poor prognosis if not diagnosed promptly. Currently, there is no optimal therapeutic scheme to eradicate the pathologies these protozoa cause. In this study we report the morphological and molecular identification of three species of the genus Acanthamoeba, belonging to T4 group; A. polyphaga isolated from the corneal ulcer of a patient sample of AK case; A. castellanii isolated from the contact lens of an AK patient and A. palestinensis obtained from a soil sample. The in vitro activity of chlorhexidine, itraconazole and voriconazole drugs against trophic stage was also evaluated through a colorimetric assay based on the oxidation-reduction of alamar blue. The strains in the study were sensitive to the evaluated drugs; although when determining the 50% inhibitory concentration (IC 50 ) statistically significant differences were observed. A. castellanii showed to be highly sensitive to voriconazole (0.66 ± 0.13 μM) but the least sensitive to chlorhexidine and itraconazole (8.61 ± 1.63 and 20.14 ± 4.93 μM, respectively), A. palestinensis showed the highest sensitivity to itraconazole (0.502 ± 0.11 μM) and A. polyphaga expressed moderate sensitivity to chlorhexidine and itraconazole and lower sensitivity to voriconazole (10.10 ± 2.21 μM). These results showed that species of the genus Acanthamoeba express different sensitivity to the tested drugs, which could explain the problems surrounding the establishment of a treatment of choice in the infections caused by these amoebae. We consider that although chlorhexidine and itraconazole show good activity on these amoebae and have been used in cases of AK in Mexico with acceptable results, voriconazole should be considered as the first therapeutic option of future Acanthamoeba infections that will be diagnosed in our country., (Copyright © 2019. Published by Elsevier Inc.)

Acanthamoeba keratitis (AK) is a sight-threatening corneal infection. The early symptoms include redness, pain, photophobia and intense tearing. Chronic infection usually progresses to stromal inflammation, ring ulcers, corneal opacification and hypopyon. Here we document an AK case in a high myopic 38-year-old woman from Mexico City, with a history of wearing contact lenses while swimming. Corneal scrapes cultures were positive only for amoebae, consequently a treatment including netilmicin 0.3% and oral itraconazole 100 mg/12 h was prescribed. The infection was resolved after 8 months, leaving a slight leucoma outside the visual axis, with a visual acuity of 20/150. In the laboratory, the amoebic isolate was axenized in PYG medium, with an optimal growth at 30 °C, and was identified morphologically as Acanthamoeba polyphaga according to the taxonomic criteria of Page (1988) and placed in the T4 group by genotyping. The virulence of this strain (40%) was determined by intranasal inoculation of 1 × 10 6 /20 μl trophozoites in BALB/c mice recovering from brain, proving their invasion ability and by the interaction with monolayers of epithelial cells of the established MDCK line of canine kidney origin (1:2 ratio of interaction), at 1, 3, 6, 8 and 24 h; trophozoites migrated to cell junctions inducing few lytic zones. In addition to the biological characterization, in vitro drug sensitivity tests were performed using chlorhexidine, itraconazole, netilmicin and voriconazole. Results revealed that voriconazole was the most effective compound. A. polyphaga remains as one of the most frequently isolated species producing AK. The treatment of AK case using netilmicin and oral itraconazole solved the disease, but the healing process was wide-ranging (8 months). The use of voriconazole and chlorhexidine may be an alternative treatment of future AK cases in Mexico., (Copyright © 2018. Published by Elsevier Inc.)

Purpose: This paper aims to evaluate the antimicrobial resistance of Esherichia coli isolates from children under 5 years old, with and without diarrhoea, who were hospital outpatients in Culiacan, Sinaloa, Mexico. It also looks at the antimicrobial activity of fruit extracts against selected multidrug-resistant (MDR) E. coli strains., Methodology: A total of 205 E. coli isolates from stool samples were collected from 94 children under 5 years old who were outpatients from two hospitals in the city of Culiacan, Sinaloa, Mexico, during the autumn/winter of 2003/04; their resistance profiles to 19 commercial antimicrobials were investigated using the Kirby-Bauer method. The antibacterial activities of extracts/fractions of fruits (i.e. uvalama, Vitex mollis; ayale, Crescentia alata; and arrayan, Psidium sartorianum) were evaluated using the broth microdilution method., Results: All E. coli isolates were susceptible to amikacin, nitrofurantoin and meropenem, and approximately 96 % were resistant to at least one antimicrobial, especially carbenicillin (93.2 %), cefuroxime sodium (53.7 %), ampicillin (40 %) and trimethoprim/sulfamethoxazole (35.1 %). Likewise, the frequency of MDR strains (44.9 %) was high, and no significant association with diarrhoea symptoms was found. Remarkably, all fruit extracts/fractions showed antibacterial activity against some, but not all, MDR isolates. The lowest minimal inhibitory concentration values were for the hexane fraction of arrayan (0.25 mg ml-1)., Conclusion: A high number of antimicrobial-resistant E. coli (especially to β-lactams and sulfonamides) and MDR isolates were detected in children under 5 years old, irrespective of diarrhoea symptoms; this is novel information for Culiacan, Sinaloa, Mexico. Moreover, our results showed that the studied fruit extracts/fractions are potential alternative or complementary treatments for MDR E. coli strains.

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.

Several studies have demonstrated that the serum of patients with cancer contains antibodies that react with a group of autoantigens denominated tumor-associated antigens (TAA). TAA can be detected prior to clinical diagnosis; thus, they would be ideal biomarkers for early detection of cancer, using only a few microliters of a patient's serum. In the current study, we used an immune proteomic approach, combining two-dimensional (2D) electrophoresis, Western blot, and matrix-associated laser desorption/ionization-mass spectrometry (MALDI-MS) methods to identify TAA in the sera of patients diagnosed with breast cancer. Sera were obtained from 36 newly diagnosed patients with stage II breast cancer and those from 36 healthy volunteers were evaluated for the presence of the TAA. Alpha 2HS-glycoprotein (AHSG) antibodies were detected in 33 of 36 patients with breast cancer (91.7%) and in only 3 of 36 healthy patients (controls, 8.3%). Sensitivity of detection of autoantibodies against AHSG in patients with breast cancer was 91.7%. AHSG was detected in cancer tissue by immunohistochemistry. Our results strongly suggest that the presence of serum autoantibodies against AHSG protein may be useful as serum biomarkers for early-stage breast cancer screening and minimally invasive diagnosis in Mexican populations., Biological Significance: In the present study, 2D immunoblot analysis was used to make a screening in samples of sera from patients with a diagnosis of early-stage breast cancer, in order to identify some autoantibodies that react against TAA. Proteins identified in the present study, particularly alpha 2HS-glycoprotein (AHSG), might be useful as potential biomarkers for breast cancer in early stages for Mexican populations., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The goal of this research is to find a more effective treatment for tequila vinasses (TVs) with potential industrial application in order to comply with the Mexican environmental regulations. TVs are characterized by their high content of solids, high values of biochemical oxygen demand (BODs), chemical oxygen demand (COD), low pH and intense colour; thus, disposal of untreated TVs severely impacts the environment. Physicochemical and biological treatments, and a combination of both, were probed on the remediation of TVs. The use of alginate for the physicochemical treatment of TVs reduced BOD5 and COD values by 70.6% and 14.2%, respectively. Twenty white-rot fungi (WRF) strains were tested in TV-based solid media. Pleurotus ostreatus 7992 and Trametes trogii 8154 were selected due to their ability to grow on TV-based solid media. Ligninolytic enzymes' production was observed in liquid cultures of both fungi. Using the selected WRF for TVs' bioremediation, both COD and BOD5 were reduced by 88.7% and 89.7%, respectively. Applying sequential physicochemical and biological treatments, BOD5 and COD were reduced by 91.6% and 93.1%, respectively. Results showed that alginate and selected WRF have potential for the industrial treatment of TVs.

Objective: To evaluate through functional teeth index, the impact in schoolchildren in communities with and without dental community support., Material and Methods: A cross-sectional study was carried out in communities with dental care provided by dental clinics of Sinaloa State University. The study sample was 2,083 schoolchildren. We used the criteria proposed by WHO for the index of decayed, missing-teeth (DMFT) for permanent dentition, index for prima- ry teeth (dmft) and the rate of functional teeth (RFT). For bivariate analysis, the nonparametric tests Pearson f and Mann-Whitney U were used., Results: The comparisons of DMFT (0.20) and RFT (13.95) of children with and DMFT (0.43) and RFT (14.82) of children without community dental support showed statistical significant difference (p < 0.05). There was a statistically significant difference in DMFT and RFT between samples with and without community dental support (p < 0.05). The age showed a statistically significant difference between the DMFT and dmft (p < 0.05). Primary dentition required more dental care than permanent dentition. There was access for dental treatment, but it is not used for the population., Conclusions: The RFT provided precise information than DMFT, mainly due to register the changes of actions focused to recover the teeth function in the oral cavity.

Background: Lung cancer (LC) is the leading cause of mortality caused by neoplasias worldwide. Although cigarette smoking is the primary cause, not all smokers develop LC. Polymorphic variations in genes associated with carcinogen metabolism, DNA repair, and cell-cycle dysregulation may alter an individual risk of developing LC. A polygenic cancer model was proposed, which considers genetic susceptibility to cancer is a global mechanism and suggests that it might be defined by the contributions of low-risk alleles in several candidate genes. This study focused on the analysis of 15 polymorphisms in 12 low-penetrance genes in a case-control study of a sample of Mexican Mestizo population., Methods: A case-control study was performed with a total of 572 unrelated individuals, including 190 cases with a primary LC diagnosis and 382 healthy controls. The polymorphic status of the individuals was determined by TaqMan probe and RFLP techniques. The association between LC and genotype score (GS) was assessed by logistic regression., Results: The results suggests a protective effect of the genotypes Arg/Lys of AhR rs2066853 (odds ratio [OR] 0.55, p = 0.03), Ile/Val of CYP1A1 rs1048943 (OR 0.49, p = 0.009), Tyr/His of EPHX1 rs1051740 (OR 0.53, p = 0.03), and A/A of CCND1 rs603965 (OR 0.44, p = 0.02). Analyses using the GS suggest that average cases have a larger number of risk alleles than controls (Student's t test -4.85, p = 0.001; OR 1.25, p < 0.001)., Conclusions: Our results suggest significant differences between the GS for the cases and controls, which support the hypothesis underlying the additive and polygenic models for lung cancer risk depending on the polymorphisms in low-penetrance genes.

Immunologic and genetic factors are involved in HIV-1/AIDS pathogenesis. Defensins are key molecules in innate immunity that participate in the control and/or development of infection and disease. Using PCR-RFLPs, we determined the association between HIV-1/AIDS and human β-defensin 1 (DEFB1) 5'UTR -52 G/A (rs1799946), -44 C/G (rs1800972), and -20 G/A (rs11362) polymorphisms in three groups of women from the state of Sinaloa, located in the Northwest region of Mexico: i) healthy blood donors; ii) sex-workers; and iii) HIV-1 patients. The -52GG genotype was more frequent in blood donors than in patients (p= 0.023; Odds Ratio, OR= 0.49; 95% CI= 0.25-0.95), whereas the - 52GA genotype was significantly higher in patients (p= 0.013; OR= 2.03; 95% CI= 1.11-3.79, statistical power SP= 98.8%), as well as the frequencies of -20A allele (p= 0.017; OR= 1.60; 95% CI= 1.06-2.40), -20AA genotype (p= 0.047; OR = 2.02; 95% CI= 0.93-4.33) and the ACA haplotype with respect to healthy blood donors (p= 0.000012; OR= 5.82; 95% CI= 2.33-16.43, SP= 99.89%) and sex-workers (p= 0.019; OR= 2.18; 95% CI= 1.07-4.46). Conversely, the ACG haplotype was higher in healthy blood donors than in patients (p= 0.009; OR= 0.55; 95% CI= 0.34-0.89). In addition, the -44CC genotype was associated with a low plasma viral load (p= 0.015), whereas AGA, AGG and GGA haplotypes were more prevalent in individuals with high CD4 counts (p= 0.004, 0.046, and 0.029, respectively). These findings associate DEFB1 5'UTR polymorphisms with HIV-1/AIDS in Mexican women for the first time.

Introduction: The Objective Structured Clinical Examination (OSCE) is a widely used measurement tool to assess clinical competence in the health sciences. There is little published evidence of its use in Mexican medical schools., Objective: To assess clinical competence in medical students with an OSCE, before and after the Medical Internship., Methods: Prospective cohort study, pre- post-test research design. The assessed population was medical students at UNAM Faculty of Medicine in Mexico in their Internship year. The instrument was an 18-stations OSCE, three stations per academic area of the Internship curriculum., Results: We assessed the clinical competence of 278 students in a pretest OSCE when starting the Internship year, and tested them 10 months later with an equivalent post-test OSCE. The sample of students was 30.4% of the total Internship population. Test reliability with Cronbach's alpha was 0.62 in the pre-test and 0.64 in the post-test. The global mean score in the pretest OSCE was 55.6 ± 6.6 and in the post-test 63.2 ± 5.7 (p < 0.001), with a Cohen's d of 1.2., Conclusions: The clinical competence of medical students measured with an OSCE is higher after the medical internship year. This difference suggests that the internship can influence the development of clinical competence in medical students.

Background: The spinal injuries in workers have become a large scale health problem. The purpose of this study is to review the differences in the spine pathologies from incapacity to work, as well as factors that could alter the recovery time and the possibility of returning the patient to work., Methods: Statistical preliminary review study in 37 patients enrolled in the Instituto Mexicano del Seguro Social, workers, undertaken to spinal pathology surgery, comparing days of incapacity with proposed internationally, as well as his return to work., Results: The results show that 37% of the patients studied are still active in the social security, 2 years after surgery. The days of disability generated by the pathology in this study group (212.3 days) are significantly higher than what is set on the Medical Disability Advisor (56 days, almost 4 times more)., Conclusion: The study shows the need to develop the same analysis in other hospitals, comparing the proportion of cases that return to the work and total disability times for diagnostics.

Objective: To analyze the caries risk through the Bratthall's Cariogram (BC) and the frequency of dental caries in a Mexican northwest children population for 12 months period., Material and Methods: A cohort of 583 scholar children between 6 and 10 years old from Sinaloa state was involved for 12 months period (2007-2008). The Bratthall's Cariogram was used to predict caries risk and the. WHO's criteria were used to obtain the caries index. The caries risk association with clinical variables was analyzed by logistic regression analysis and Sperman's Rho rank correlation test was used to evaluate the correlation between DMFT index and BC., Results: The caries risk increased with respect to age (p < 0.05), the CB identified correctly children for high risk (85%) and low risk (65%) caries for a 12 months period. The baseline values of BC showed a positive correlation with DMFT index (0.86 and p = 0.0001); the diagnostic test evaluation showed the following values: positive predictive value of 87%, negative predictive value of 63%, sensitivity of 93% and specificity of 63%., Conclusions: The caries risk increased with the age in the studied population. The Bratthall's Cariogram is a useful screening test to evaluate the risk for dental caries at individual and population levels.

Background: There are few studies regarding the measurement of tracheal dimensions. Most are focused on morphology and tracheal development. The aim of this study was to determine the length and tracheal diameter of adults in our population and its correlation with external measurements., Methods: The study design was prospective, observational and descriptive. We included a nonrandom sampling of deaths of Mexican national citizens who were between 18 and 65 year old. The study period was from June 1 to November 30, 2009, and the study was carried out at the facilities of the Forensic Medical Service of the Federal District, Mexico. Standardized measurements of tracheal diameter and length were correlated with external measurements., Results: We dissected 44 cadavers, 19 (43%) females and 25 (57%) males. In females the average age was 39.2 ± 13.9 years (range: 19-61 years), average height 161.9 ± 7.4 cm (range: 154-179 cm), tracheal length (TL) 8.6 ± 0.5 cm (range: 7.8-9.5 cm) and transverse diameter (TD) 1.7 ± 0.3 cm (range: 1.3-2.0 cm). Average age of males was 36.4 ± 14.4 years (range: 19-65 years), average height 169.8 ± 6.7 cm (range: 156-184 cm), TL 9.1 ± 0.9 cm (range: 8.0-10.7) and TD 1.9 ± 0.2 cm (range: 1.6-2.3 cm). TL was significantly correlated with sternal length (0.82, p <0.0001) and age (0.56, p = 0.0003). According to gender, there was no significant correlation between TL and height., Conclusions: We found a low average TL and no significant correlation with height. These data should be considered when carrying out direct procedures on the trachea.

Introduction: In Mexico cancer is a public health burden. Nowadays the health care systems pay special attention to patient's perception and satisfaction of the health care received. Satisfaction with quality of health care has an impact in the adherence to the treatment., Objective: To evaluate the satisfaction with the quality of health care received at the IMSS in a group of cancer patients [non Hodgkin lymphoma (NHL), breast and colorectal cancer]. Socio-demographic features, co-morbid diseases, and attendance processes impact on satisfaction are also evaluated., Results: 476 cancer patients were studied: 314 with breast cancer, 92 with NHL and 70 with colorectal cancer. In women with breast cancer the mean score to nurses' interpersonal skills in non-classified disease group and clinical stage III group were: 73.64 ± 32.53, 90.00 ± 18.25 respectively (p=0.005), nurses' availability in non-classified and clinical stage III group were: 69.71 ± 30.25, 89.21 ± 19.00 respectively (p=0.003). In subjects with NHL the mean scores for doctors' technical skills in clinical stage I and III groups, were: 63.69 ± 37.78, 80.30 ± 18.46 respectively (p=0.017), doctors' information provision scores in subject in clinical stage I and IV were: 49.40 ± 40.75, 79.49 ± 24.63 respectively (p=0.043). In the group of colorectal cancer patients the mean of the score to exchange of information between clinical stage II and clinical stage III group were 50.00 ± 41.83, 84.21 ± 22.37 respectively (p=0.036). Were not observed association between attendance processes features and general satisfaction., Conclusions: In Mexico 50% of cancer patients are attended at the IMSS. The continued evaluation of the satisfaction with health care received by the health care service users is important to enhance attention's quality., (Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.)

Introduction: Quality of life is the most studied PRO (patient reported outcome) in cancer patients. With early diagnosis and better treatments in breast cancer, this entity has been transformed in a chronic disease with longer survival. The joint effects of diseases and treatment on quality of life are each day more important to consider in survival patients., Objective: To evaluate quality of life, socioeconomic factors, co-morbidities, and the attendance process impact on quality of life in breast cancer women with different clinical stages attending at the Instituto Mexicano del Seguro Social using the EORCT QLQ-C30, Results: The scores of EORTC QLQ-C30 (v3) were: Global health status / QoL: 73.47 (± 20.81), physical functioning 76.98 (± 20.85), role functioning 76.60 (± 27.57), emotional functioning 64.53 (± 26.81), cognitive functioning 74.47 (± 26.02), social functioning 84.96 (± 23.20), fatigue 31.94 (± 25.45), nausea and vomiting 19.49 (± 26.93), pain 28.95 (± 27.27), dyspnea 15.29 (± 24.62), insomnia 35.13 (± 32.10), appetite lost 18.04 (± 28.75), 18.04 (± 28.75), constipation 19.20 (± 32.11), diarrhea 12.9 (± 24.25), financial difficulties 40.57 (± 37.26). The scores with EORTC QLQ-BR23 were: body image 74.84 (± 31.69), sexual functioning 13.73 (± 22.55), sexual enjoyment 32.86 (± 36.17), future perspectives 51.69 (± 38.00), systemic therapy side effects 30.82 (± 20.71), breast symptoms 22.85 (± 23.49), arm symptoms 27.53 (± 24.75), upset by hair loss 43.80 (± 44.01)., Conclusions: Clinical stage in breast cancer is associated with differences in the scores from fatigue, nausea and vomiting and financial difficulties according to the evolution of the disease and the physical detriment associated. Socio-demographic features were related role functioning, fatigue and pain in single women with higher scores., (Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.)

Introduction: In Mexico during 2008, were reported 127,604 new cancer cases, 6,347 of them were colorectal cancer cases and 4,276 non-Hodgkin lymphoma (NHL) cases., Objective: To evaluate health related quality of life in non-Hodgkin lymphoma and colorectal cancer cases in different clinical stages, attended in a High Specialty Medical facility at the Instituto Mexicano del Seguro Social, during a 13 month period., Results: 162 patients were included, 56.8% (n=92) with NHL and 43.2% (n=70) with colorectal cancer. The scores obtained in the NHL group were: Global health status/QoL: 67.75 (± 27.55), physical functioning 69.64 (± 29.98), role functioning 71.38 (± 33.73), emotional functioning 69.7 (± 26.57), cognitive functioning 75.36 (± 28.01), social functioning 79.35 (± 29.38), fatigue 35.27 (± 28.27), nausea and vomiting 13.41 (± 21.85), pain 28.08 (± 30.25), dyspnea 19.20 (± 32.11), insomnia 30.80 (± 38.03), appetite lost 26.45 (± 36.16), constipation 19.20 (± 32.11), diarrhea 12.32 (± 26.48), financial difficulties 26.09 (± 35.57). In colorectal cancer patients the scores were: Global health status/QoL: 68.21 (± 24.46), physical functioning 67.38 (± 30.45), role functioning 65.48 (± 35.70), emotional functioning 66.43 (± 26.84), cognitive functioning 78.57 (± 26.49), social functioning 75.24 (± 31.05), fatigue 37.78 (± 31.62), nausea and vomiting 20.00 (± 28.32), pain 37.38 (± 34.45), dyspnea 11.90 (± 26.64), insomnia 28.09 (± 35.73), appetite lost 23.81 (± 36.40), constipation 19.05 (± 32.88), diarrhea 20.95 (± 31.17), financial difficulties 34.76 (± 38.67)., Conclusions: With these basal results is important a follow-up with special attention to the treatment and attendance processes, in patients with this neoplasms and their impact on the quality of life., (Copyright © 2011 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.)

Background: The origin of spindle cells (SC) in oral Kaposi's sarcoma (OKS) is still an intriguing aspect. Thus the aim of the present study was to compare the clinical, histological and immunohistochemical characteristics of OKS and oral pyogenic granuloma (OPG), in order to contribute to the knowledge of the cells involved in Kaposi's sarcoma pathogenesis., Methods: In this retrospective, observational and comparative study, 39 OKS and 30 OPG cases were included. Immunohistochemical studies were performed for vimentin, alpha SMA, desmin, C-kit, CD34, D2-40 and LANA-1 [human herpesvirus-8(HHV-8)]. Statistical comparisons were done using the chi-square and Wilcoxon-Mann-Whitney rank sum tests., Results: Fourteen (35.9%) OKS cases also affected the skin, and 83.8% involved the palate. All OKS and OPG were positive for vimentin and CD34. OKS samples were positive for alpha SMA, and 25.6% expressed C-kit. All OKS cases were positive for HHV-8, and the number of positive cells increased significantly from early / intermediate to late histological stage. D2-40 was expressed in the cellular component and vascular walls of all OKS cases, but it was negative in OPG. HHV-8 expression was increased in late histological stages of OKS lesions., Conclusions: The expression of D2-40 marker in the vascular walls and SC supports the view of a lymphatic differentiation in neoplastic cells of OKS. Desmin, alpha SMA, D2-40, C-kit and HHV-8 were the main markers differently expressed in OKS and OPG.

Objective: The purpose was to estimate the prevalence of smoking in adolescents and its association with some individual and family characteristics in urban and rural areas., Methods: An analytic cross-sectional study was carried out in 3161 junior high school students, of eight public and two private urban schools and three public rural schools. Some student behaviors on tobacco use, patterns of smoking and alcohol consumption in the family and socioeconomic status were measured., Results: The prevalence of smoking increased with age. In private urban schools, women had a higher prevalence that males (27.6 % vs. 19.3 %). In rural area schools was higher in males (9.9 % vs. 3.5 %). Individual characteristics associated with smoking were: the curiosity to smoke (OR = 9.7, CI 95 % = 5.8-16.3), having experienced with smoking (OR = 26, CI 95% = 12-56.6) and alcohol consumption (OR = 2.9, CI 95 % = 2.1-3.9). The family characteristics that influence adolescent smoking were the presence of smoking habit in the father (OR = 1.5, CI 95% = 1.1-2) or in the brother or sister (OR = 2, CI 95 % = 1.3-3). The parents living together (OR = 0.6, CI 95 % = 0.4-0.9) was a protective factor., Conclusions: The exploratory behavior of the adolescent and the patterns of tobacco use and alcohol consumption in the family influenced the adoption of this habit.

Unlabelled: The aim of this work was to propose an adjustment to the Model of Andersen who answers better to the social inequality of the population in the Mexico City and allows to evaluate the effect of socioeconomic factors in the access to the prenatal care of a sample stratified according to degree of marginalization., Material and Methods: The data come from a study of 663 women, randomly selected from a framework sample of 21,421 homes in Mexico City. This work collects information about factors that affect utilization of health services, as well as predisposing factors (age and socioeconomic level), as enabling factors (education, social support, entitlement, pay out of pocket and opinion of health services), and need factors. The sample was ranked according to exclusion variables into three stratums. The data were analyzed through the technique of path analysis., Results: The results indicate that socioeconomic level takes part like predisposed variable for utilization of prenatal care services into three stratums. Otherwise, education and social support were the most important enabling variables for utilization of prenatal care services in the same three groups. In regard to low stratum, the most important enabling variables were education and entitlement. For high stratum the principal enabling variables were pay out of pocket and social support. The medium stratum shows atypical behavior which it was difficult to explain and understand. There was not mediating role with need variable in three models. This indicated absence of equality in all stratums. However, the most correlations in high stratum perhaps indicate less inequitable conditions regarding other stratums.

Background: The aim of the present study was to compare the prevalence of HIV-related oral lesions (HIV-OL) between two health centers for HIV in Mexico City and to analyze the factors that, in addition to combined antiretroviral therapy (CART) and low CD4(+), may be associated with possible differences in prevalence., Methods: A cross-sectional observational study was performed between January 2000 and February 2003 at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán (INCMNSZ), a specialized referral center for HIV/AIDS patients and the Clínica Especializada Condesa (CEC), a primary care center for HIV-infected individuals without social security insurance. A consecutive sample of HIV-infected individuals had an oral examination based on established clinical criteria. Demographic, clinical and laboratory data were obtained. Independent association of each factor with specific HIV-OL was assessed by logistic regression modeling., Results: Eight hundred fifty individuals were examined (INCMNSZ: 479; CEC: 371). Hairy leukoplakia (HL), periodontal disease (PD) and Kaposi's sarcoma (KS) were independently associated with the study site [odds ratio (OR) = 1.7 (95% confidence interval (CI): 1.1-2.4), OR = 4.2 (95% CI: 1.3-13), OR = 10.1 (95% CI: 2.7-38.2), respectively], being more frequent in CEC patients. HL was independently associated with men having sex with men OR = 1.7 (95% CI: 1.1-2.8). All HIV-OL were independently associated with CD4(+) counts and, with the exception of PD and KS, with time under CART., Conclusions: The present comparative study showed that several factors were associated with a difference in prevalence of oral lesions found in two AIDS clinics located in Mexico City. Severe immune suppression, CART duration and the study site were associated with HIV-OL. Further investigation into factors such as socioeconomic determinants associated with HIV-OL is warranted.

Purpose: To examine the prevalence of coronary risk factors in Mexican adolescents, and their relations to school type, gender, and residence in urban and rural areas., Methods: A cross-sectional survey was conducted in 3121 junior high school students, aged 12 to 16 years, attending urban schools (eight public, n = 1850, two private, n = 480) and three rural public (n = 791) schools. Weight, height, waist circumference, blood pressure, and fasting glucose and lipid-lipoprotein levels were measured. Tobacco smoking and physical activity were also ascertained. The prevalence rates of cardiovascular risk factors were determined by gender and school type., Results: Obesity, overweight, high blood pressure, cigarette smoking, and physical inactivity were higher for urban than rural adolescents. The prevalence of the low HDL-C level was exceedingly high in adolescents of three school types (> 30%) but particularly in male rural students (48.9%). Compared with rural students, high LDL-cholesterol was twice as high in private schoolchildren. The prevalence of impaired fasting glucose was .35% in the whole population and much higher in obese males (1.6%) and obese females (2.4%)., Conclusions: Our findings highlight an epidemic of coronary risk factors mainly in adolescents living in the urban area, suggesting the importance of environmental factors.

Objective: To evaluate the accuracy of the self-reported body mass index and body image perception in a population of Mexican adults., Material and Methods: In 1998, in the state of Morelos, Mexico, participants in the longitudinal study of Mexican Social Security Institute workers "IMSS Cohort Study" responded to a baseline, self-administered questionnaire designed to collect a large variety of lifestyle risk factors for chronic diseases. Participants self-reported their body image by selecting the silhouette that best portrayed them, from a set of silhouettes ranked from 1 to 9. Participants also self-reported their current weight and height, unaware that direct measurements of weight and height were to follow. Four to eight months later participants were weighed and their heights were measured using standardized procedures. Spearman correlations were computed to analyze the correlation between self-reported and measured data. The Kruskal-Wallis test was used to evaluate the magnitude of difference between measured and self-reported height, weight and body mass index (BMI) (measured minus self-reported), by educational level and categories of age. Robust regression was used to evaluate the potential effect of specific individual characteristics on differences between measured and self-reported weight and height. Logistic regression analysis was used to evaluate the sensitivity, specificity, and predictive values for BMI., Results: The study included 934 subjects, of which 62.6% were female. Females had a mean measured height of 1.55 m (SD 0.06) and weight of 65.4 kg (SD 10.9), while males had a mean height of 1.67 m (SD 0.06) and weight of 77.7 kg (SD 12.5). The mean BMI was 27.4 kg/m2 (SD 4.3) (females: 27.2 kg/m2 +/- 4.45; males: 27.8+/-3.87). The median of body image perception (BIP) was 5 (25th percentile=4; 75th percentile=6). Correlations between measured and self-reported height, weight, and BMI for all subjects were 0.94, 0.96, and 0.90, respectively. The correlation between BMI and BIP was 0.64 (0.67 for females and 0.59 for males). Self-reported mean varied no more than 1.3 cm from measured height and no more than 3.17 kg from measured weight. Error estimations of height, weight, and BMI decreased with educational level. Sensitivity and specificity before adjusting self-reported BMI with overweight and obesity categories that were collapsed into one were 94.8 and 83.0%, respectively; for BIP, those values were 87.6 and 48.9%., Conclusions: The results suggest that self-reported BMI and BIP can be useful indicators of an overweight condition in Mexican adults. The sensitivities and specificities associated with corrected self-reported BMI categories could be used to adjust odds ratios and relative risks, calculated from BMI levels derived from the self-reported BMI. Body image perception made it possible to correctly classify individuals with BMI > or = 25, showing that it may be a valid estimate for use in epidemiological surveys.

Lower back pain has a high prevalence among the Mexican working population, with extensive social and economic repercussions. Official figures show that lower back pain accounts for 10.0 to 15.0% of sick leave excuses. However, this fails to identify any relationship between lower back pain and job conditions, since such leave is only granted if it can be shown that the condition was not work-related. The present study shows that such a relationship does in fact exist. A retrospective study examined all cases (n = 210) in which workers were granted sick leave for lower back pain in an IMSS (Mexican Government Health Insurance) hospital in Mexico City during a seven-year period. The results show the association and interactions between debilitating lower back pain and several work-related variables: job position, time-on-the-job, and physical effort and weight-carrying associated with the position. Causes of lower back pain and the difficulty in obtaining accurate, precise back pain diagnosis are discussed. A number of clinical, epidemiological, and legal strategies for the study and prevention of back pain are suggested.

The report describes an HIV/AIDS patient seen at a referral center in Mexico City, in whom a mycobacterial infection in the oral mucosa, probably tuberculosis (TB) was identified. The purpose is to describe the clinical and histological findings in an HIV-infected patient, who after being treated successfully for tuberculous lymphangitis 4 years ago, presented with a lingual ulcer as the only suggestive sign of recurrence of mycobacterial infection, probably M. tuberculosis. A 39-year-old man seen in the HIV clinic of the Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán" in Mexico City since 1991 for HIV infection. In 1999 the patient developed tuberculous lymphangitis; he was managed with a 4-drug regimen for 12 months, with improvement of local and systemic symptoms. In May of 2003, the patient presented a painful superficial lingual ulcer, 0.7 cm in diameter, well circumscribed, crateriform with slightly elevated, irregular and indurated borders, of 4 months duration. The histopathological examination showed chronic granulomatous inflammation with giant multinucleated cells, suggestive of mycobacterial infection, and recurrence of TB was considered. Rifampin, isoniazide, pyrazinamide, ethambutol and streptomycin were administered. The lingual lesion improved with partial healing at the first week and total remission at 45 days after the beginning of the antituberculous treatment. In June, 2003, the patient began highly active antiretroviral therapy (HAART) that included two NRTIs and one NNRTI. At 7 months of follow-up, the patient remains free of lingual lesions. The particularity of the present case is that the lingual ulcer was the only sign of infection by mycobacteria, suggestive of TB, in an HIV/AIDS patient that probably represented a recurrence of a previous episode.

Objective: To evaluate the construct validity and the internal reliability of the Subjective Symptoms of Fatigue Test (SSFT), as well as to establish its best cutoff point., Materials and Methods: The SSFT was developed in Japan to measure fatigue in a population of workers; the test includes 30 items in three spheres. Construct validity was explored through differences among groups, using a population of 1399 workers from eight industries studied in Mexico City in 1999. We used the Theorell and Karasek's control-demand model as our nomological network, from which we derived two work hypotheses. Workers were divided into nine groups according to their level of control-demand; fatigue differences were assessed using analysis of covariance. The internal reliability level was tested with Cronbach's alpha. The cutoff point was obtained by means of the expected linear relation between the labor demands and fatigue., Results: The distribution of SSFT values was similar to the expected values, increasing proportionally with increasing demands or with decreasing control. The differences between groups were statistically significant. Cronbach's alpha was 0.89, while the value per sphere was always above 0.70. The cut-off points most closely correlated were 6 and 7 affirmative answers., Conclusions: The observed score obtained in the distinct groups was as expected, in agreement with the study hypotheses. The internal reliability of the test was adequate. The proposed cutoff point for the general population was seven affirmative responses.

Cluster analysis was applied to determine, the natural grouping of individuals, among sixty 8-10-year-old children, and to identify the most significant set of markers for risk assessment. The risk clusters were obtained with initial clinical and bacteriological measurements including dmf + DMFS, active caries, mutans streptococci and lactobacilli counts in plaque or saliva on two media, and Snyder's test results. The morbidity clusters were constructed with the final clinical indexes and incidence after 18 months (dependent variables). A risk cluster was identified that included the following significant initial variables; dmf + DMFS, active caries, counts of mutans streptococci from plaque on TSY20B and lactobacilli in saliva, and Snyder's test results. This set of markers identified 86% of the children at high risk who developed high morbidity, as well as 94% of children in the low-risk cluster who developed low or no caries. The results of this investigation provide the basis to develop a system for caries risk assessment.

Background: Our objective was to develop prediction equations for spirometric parameters that included the following: forced vital capacity (FVC); 1st-sec forced expiratory volume (FEV1); FEV1/FVC ratio; peak expiratory flow (PEF); maximal expiratory flow 50% FVC (VF50) and maximal expiratory flow 75% FVC (VF75); maximal mid-expiratory flow (FEF25-75), and forced late expiratory flow rate (FEF75-85) in a sample of adult Mexican population of both sexes. Age and height variables were utilized., Methods: Spirometric studies were carried out, observing the international recommendations and norms in force and effected under basal conditions and post-bronchodilator. Linear regression equations were generated based on gender, age, and height. For each spirometric parameter, we selected a linear model. Studies were carried out with spirometry that was in agreement with quality criteria recommended by the American Thoracic Society (ATS). Bronchodilatator administration allowed for elimination of subjects with subclinical bronchial hyperreactivity, Results: We studied 436 patients with normal clinical radiographic and pulmonary function, with negative smoking and age range between 17 and 63 years; 206 were females and 230, males. Linear regression equations obtained had direct linear correlation with height and inverse linear correlation with age; in addition, equations had a determination coefficient equal to or less than those reported by authors recommended by the ATS., Conclusions: Equations obtained in this study possessed the quality required for application in adult Mexican population exposed or not to occupational and environmental contaminants.

An increasing number of human cases of gnathostomiasis have been reported in Sinaloa, Mexico, most of whom have a custom of eating of raw fish dishes such as 'cebiche'. Here we report five adult patients, three women and two men, having an acute episode of vomiting and abdominal pain a few minutes after eating a dish of cebiche prepared from a spotted sleeper perch (Eleotris picta) fished from a nearby lake in southern Sinaloa. All five patients experienced acute throat pain, chest and joint pains, headache and fever. One patient, a 55-year-old male, was hospitalized with suspected pancreatitis and pneumonia. By 8-9 days later, all five patients developed between three and 12 edematous, migrating skin lesions on the back, abdomen, upper and lower extremities, face, eye and scalp. By ELISA, all of them were sero-positive to Gnathostoma doloresi antigen and had elevated IgE levels. Eosinophilia was found in two patients. These patients lived in an agricultural and fishing community. In this community we carried out a sero-epidemiological survey and study of living conditions in a random sample of 309 individuals distributed in 74 households. Frequent consumption of raw fish was reported in 36% of households, and 12 individuals had a clinical history of migrating skin lesions. The sero-prevalence to Gnathostoma antigens was 34.95%. Five fish species and four species of ichthyophagous birds collected from three lakes in the village and a nearby estuary were infected with the advanced third-stage larvae of G. binucleatum, a species found in Ecuador and Mexico. The results describe the first known outbreak of acute gnathostomiasis on the American continent.

Objective: To evaluate the association between video display terminal (VDT) use and health hazards, occupational risks, and psychosocial factors, in newspaper workers., Materials and Methods: A cross-sectional study was conducted in 1998 in a representative sample (n = 68) drawn from a population of 218 VDT operators in Mexico City. Data were collected using a self-administered questionnaire. Data were confirmed by performing physical examinations. The research hypothesis was that both the current and cumulative use of VDT are associated with visual, musculoskeletal system, and skin illnesses, as well as with fatigue and mental or psychosomatic disorders. Occupational health hazards were assessed (visual problems, postural risks, sedentary work, computer mouse use, excessive heat, and overcrowding), as well as psychosocial factors related to work organization (psychological demands, work control, and social support). Prevalence ratios were adjusted for confounding variables like age, sex and schooling., Results: Women were more likely than men to have upper extremity musculoskeletal disorders (MSD), dermatitis, and seborrheic eczema. VDT use was associated with neuro-visual fatigue, upper extremity MSD, dermatitis, and seborrheic eczema. Computer mouse use and postural risks were significantly associated with health problems. Psychosocial factors were mainly associated with mental problems, psychosomatic disorders, and fatigue., Conclusions: Intense use of video screens has been found to cause musculoskeletal disorders of the hand. The diversification of tasks and control of labor processes itself had a protective effect against psychosomatic disorders and pathological fatigue.

Objective: To describe the methods and analyses of the 1999 National Nutrition Survey (NNS-99)., Material and Methods: The 1999 National Nutrition Survey (NNS-99) is a probabilistic survey with nationwide representativity. The NNS-99 included four regions and urban and rural areas of Mexico. The last sampling units were households, selected through stratified cluster sampling. The study population consisted of children under five years of age, school-age children (6-11 years), and women of childbearing age (12-49 years). Data were collected on anthropometric measurements, hemoglobin levels, morbidity and its determinants, and socioeconomic and demographic characteristics. In addition, data on diet and micronutrients intakes (iron, zinc, vitamin A, folic acid, vitamin C, and iodine) were obtained in a sub-sample of subjects., Results: The response rate for the NNS-99 was 82.3%; the non-response rate was 5.9% and the remaining did not participate due to uninhabited houses., Conclusions: This survey updates the information on nutritional status in Mexico and should serve as the basis for food and nutrition policy-making and priority program design. The English version of this paper is available too at: http://www.insp.mx/salud/index.html.

In developing countries, the variations in the clinical spectrum of human immunodeficiency virus (HIV)-related oral lesions over time, and the possible effects of antiretroviral therapy, have not been described. In this study we evaluate the clinical spectrum of oral lesions in a series of HIV-infected patients when first examined at the acquired immunodeficiency syndrome (AIDS) clinic of a tertiary care institution in Mexico City, Mexico, and the changes observed over 12 years. All HIV-infected adult patients had an oral examination performed by specialists in oral pathology and medicine who used established clinical diagnostic criteria for oral lesions. Four periods were defined according to the evolving pattern of antiretroviral use: the first 2 were before the introduction of highly active antiretroviral therapy (HAART) and the last 2 were during more established use of HAART. For the statistical analysis the chi-square test for contingency tables and the chi-square test for trend were utilized. For dimensional variables, except age, the Kruskal-Wallis or Mann-Whitney rank sum tests were used when applicable and trend was tested with the Spearman correlation coefficient. Age was tested through analysis of variance (ANOVA) and linear regression analysis. Alpha value was set at p = 0.05 for each test. In the 12-year study, 1,000 HIV-infected patients were included (87.9% male). At the baseline examination, oral lesions strongly associated with HIV were present in 47.1% of HIV-infected patients. Oral candidosis (31.6%), hairy leukoplakia (22.6%), erythematous candidosis (21.0%), and pseudomembranous candidosis (15.8%) were the most frequent lesions. Oral Kaposi sarcoma (2.3%), HIV-associated periodontal disease (1.7%), and oral non-Hodgkin lymphoma (0.1%) were less frequent. HIV-related oral lesions decreased systematically-by half during the course of the 4 study periods (p < 0.001). Except for Kaposi sarcoma, all oral lesions strongly associated with HIV showed a trend to decrease significantly during the study period. No apparent variation in the occurrence of salivary gland disease or human papillomavirus-associated oral lesions was found. A significant trend to a lower prevalence was observed in the group of patients who were already taking antiretroviral therapy, non-HAART and HAART (p < 0.001 and p = 0.004, respectively). Only a discrete reduction, barely significant, was noted among untreated patients (p = 0.060). By Period IV (1999-2001), those who received HAART showed the lowest prevalence of oral lesions strongly associated with HIV (p < 0.001). Patients with oral lesions strongly associated with HIV had significantly lower median CD4+ counts and higher viral loads than those without oral lesions strongly associated with HIV (p < 0.001 and p = 0.005, respectively). When CD4+ counts were correlated with prevalence of oral candidosis, a consistently negative association was found; this association prevailed even after the study group was partitioned according to period. In this selected cohort of 1,000 patients with HIV infection, the clinical spectrum of HIV-related oral lesions has changed over the 12-year study, with a decreased prevalence of most oral lesions. Our findings probably represent improvements in medical care of HIV-infected persons, earlier detection of HIV-infected patients at the AIDS clinic, the increasing use of prophylactic drugs to prevent secondary AIDS-related opportunistic infections, and, perhaps most important, the availability of potent antiretroviral therapy in recent years, since the introduction of HAART.

Objective: To estimate the prevalence of oral lesions and its association with HIV serological status., Material and Methods: A cross-sectional descriptive study was conducted between 1998 and 1999 in Mexico City, among 512 subjects attending two information centers of Centro Nacional para la Prevención del VIH/SIDA e ITS (CONASIDA, National Center for Prevention of HIV/AIDS and Sexually Transmitted Infections) for HIV serologic testing. The oral examination was performed without knowledge of the HIV status. Statistical analysis was conducted using Student's t test, Fisher's exact test and the chi 2 test; odds ratios and 95% CI were also calculated., Results: A total of 512 individuals were examined, 68 of whom were HIV-positive. HIV-related oral lesions (OL), were evident in 65% (44/68) of the HIV-positive individuals; 95% of them consisted in oral candidosis (OC) and hairy leukoplakia (HL). OC and HL were strongly associated with seropositivity to HIV., Conclusions: OC and HL were the oral lesions most strongly associated to HIV seropositivity. The English version of this paper is available at: http://www.insp.mx/salud/index.html.

Objective: To determine the free amino acid pool in plasma and milk in Mexican rural lactating women., Methods: Twenty-eight women with an age 24 +/- 5.0 (+/- SD) years, weight 50 +/- 4.9 kg and height 148 +/- 4.8 cm were studied under metabolic balance conditions. Subjects were divided into five groups (three groups of lactation at 1st, 3rd and 6th month, one post-weaning group and a control group of non pregnant, non lactating women). Amino acid analyses of the diet and of plasma and milk samples were performed using an automated amino acid analyzer., Results: Differences were observed between the lactation groups and the other groups: aspartate increased at the 6th month (p < 0.05) while leucine, valine and isoleucine declined in the 3rd month (p < 0.05). In milk, valine, proline and taurine decreased at 6 months (p < 0.05), while serine and threonine raised at 3 months. Plasma levels were > 4 fold greater than milk levels for branched chain amino acids and for the basic, aromatic and neutral amino acids. In contrast, glutamate was 40 fold higher in milk than plasma and it was the predominant amino acid in the free pool of milk., Conclusions: Our results suggest that the metabolic use of amino acids and the presence of specific amino acid transport systems during lactation, contribute to specific concentrations of free amino acids in milk that were not associated with the pool of free amino acids in plasma.

The ingestion of rattlesnake powder capsules is frequent in Mexico in view of their alleged curative properties in various diseases, among them different malignancies. Based on previous reports showing both bacteremia and septicemia in patients with malignant diseases ingesting such capsules, we conducted a study to evaluate the presence of microorganisms in 16 different preparations of rattlesnake powder capsules, obtained in six different cities of our country. We found that all the samples were significantly contaminated with gram-negative coliform bacteria: Escherichia coli, Klebsiella pneumoniae, Enterobacter agglomerans, E. cloacae, Salmonella arizona and Salmonella of groups B, E4 and G. Eighty one percent of the capsules were contaminated with Salmonella sp. The most frequent was S. arizona with a natural reservoir in snakes. Contamination was probably derived from both the flesh of the snake and fecal contamination during the domestic preparation of the powder to produce the capsules. These data, together with those previously published regarding bacteremia and septicemia derived from the ingestion of the capsules, suggests that there is danger in their use.