An emission processing system for air quality modelling in the Mexico City metropolitan area: Evaluation and comparison of the MOBILE6.2-Mexico and MOVES-Mexico traffic emissions.

This article describes the High-Elective Resolution Modelling Emission System for Mexico (HERMES-Mex) model, an emission processing tool developed to transform the official Mexico City Metropolitan Area (MCMA) emission inventory into hourly, gridded (up to 1km2) and speciated emissions used to drive mesoscale air quality simulations with the Community Multi-scale Air Quality (CMAQ) model. The methods and ancillary information used for the spatial and temporal disaggregation and speciation of the emissions are presented and discussed. The resulting emission system is evaluated, and a case study on CO, NO2, O3, VOC and PM2.5 concentrations is conducted to demonstrate its applicability. Moreover, resulting traffic emissions from the Mobile Source Emission Factor Model for Mexico (MOBILE6.2-Mexico) and the MOtor Vehicle Emission Simulator for Mexico (MOVES-Mexico) models are integrated in the tool to assess and compare their performance. NOx and VOC total emissions modelled are reduced by 37% and 26% in the MCMA when replacing MOBILE6.2-Mexico for MOVES-Mexico traffic emissions. In terms of air quality, the system composed by the Weather Research and Forecasting model (WRF) coupled with the HERMES-Mex and CMAQ models properly reproduces the pollutant levels and patterns measured in the MCMA. The system's performance clearly improves in urban stations with a strong influence of traffic sources when applying MOVES-Mexico emissions. Despite reducing estimations of modelled precursor emissions, O3 peak averages are increased in the MCMA core urban area (up to 30ppb) when using MOVES-Mexico mobile emissions due to its VOC-limited regime, while concentrations in the surrounding suburban/rural areas decrease or increase depending on the meteorological conditions of the day. The results obtained suggest that the HERMES-Mex model can be used to provide model-ready emissions for air quality modelling in the MCMA.

Effect of HLA-B and HLA-DR genes on susceptibility to and severity of spondyloarthropathies in Mexican patients.

OBJECTIVE: To investigate the role of HLA-B and HLA-DR genes as contributors to genetic susceptibility and clinical expression of the spondyloarthropathies (SpA) in the Mexican population. METHODS: The study included 172 patients with SpA (undifferentiated SpA 83, ankylosing spondylitis (AS) 64, and reactive arthritis 25) and 99 healthy controls. The HLA-B and HLA-DR alleles were detected by the polymerase chain reaction with sequence-specific primers technique. Patient assessment included demographic data, diagnostic categories, and disease patterns. Statistical methods included the Mantel-Haenzel chi(2) test, Fisher's exact test, and Woolf method for odds ratio (OR). Differences of continuous variables between HLA allele groups were calculated by Student's t test. RESULTS: Increased frequencies of HLA-B27 (pCh10(-3), OR=28.7), HLA-DR1 (pC=0.045, OR=2.77), and HLA-B15 (p=0.034, pC=NS, OR=2.04) alleles in the whole group were found. HLA-B27 strength of association (OR) was 41.4 in AS; 20.9 in undifferentiated SpA; 27.2 in reactive arthritis. HLA-DR1 and HLA-B15 were increased in undifferentiated SpA (pC=0.045, OR=2.98 and p=0.004, pC=NS, OR=2.75). By analysing 58 HLA-B27 negative patients it was found that HLA-B15 and HLA-DR1 associations with SpA were independent of HLA-B27; increased frequencies of HLA-B15 were found in the whole SpA group and in patients with undifferentiated SpA (pC=0.03, OR=3.09 and pCh0.01, OR=3.77) and of HLA-DR1 in the latter (p=0.04, pC=NS, OR=3.15). HLA-B27 positive patients were younger than HLA-B27 negative patients at onset (p=0.03), but HLA-DR1 positive patients were older than HLA-DR1 negative patients (p=0.03). Bath indices for disease activity and functioning were higher in HLA-B27 positive patients (p=0.006 and p=0.004 v HLA-B27 negative patients). In contrast, neither HLA-DR1 nor HLA-B15 influenced these indices. CONCLUSION: Apart from HLA-B27, there is a significant association of HLA-DR1 and HLA-B15 with SpA in Mexicans which is independent of B27. HLA-B27 is associated with younger age at onset and increased disease severity and HLA-DR1 with older age at onset. The strength of HLA-B15, HLA-B27, and HLA-DR1 associations varied in different forms of SpA.

Heat shock protein 70 gene polymorphisms in Mexican patients with spondyloarthropathies.

OBJECTIVE: To investigate the role of HSP70 genes as contributors to genetic susceptibility of the spondyloarthropathies (SpA) in the Mexican population. METHODS: The study included 150 patients with SpA (undifferentiated spondyloarthropathy (uSpA) 68, ankylosing spondylitis (AS) 60, and reactive arthritis 22) and 158 healthy controls. HSP70-1, HSP70-2 and HSP70-hom genotypes were analysed by the polymerase chain reaction-restriction fragment length polymorphism technique. Statistical methods included the Mantel-Haenzel, chi(2), Fisher's exact test, and Woolf's method for odds ratio (OR). RESULTS: HSP70-2 B/B genotype frequency was increased in the whole group of patients with SpA (pC<0.05, OR=4.3), as well as in the different clinical subgroups (pC<0.05, OR=4.2 for AS; pC<0.05, OR=4.4 for uSpA; and pC<0.05, OR=4.1 for ReA). This frequency remained significantly increased when the patients with B27 negative SpA were analysed. On the other hand, HSP70-hom locus analysis showed significantly increased frequency of A allele in the whole group of SpA (pC<0.05, OR=3.4), as well as in the groups with AS (pC<0.05, OR=5.6) and with uSpA (pC<0.05, OR=3.1), when compared with healthy controls. In this case, also, the genotype A/A was increased in the whole group of SpA (pC<0.05, OR=4.5), as well as in patients with AS (pC<0.05, OR=6.4) and with uSpA (pC<0.05, OR=3.7). When the patients with B27 negative SpA were analysed the frequencies of HSP70-hom A allele and A/A genotype remained significantly increased in the whole group of SpA (pC<0.05, OR=3.2 for the A allele and pC<0.05, OR=4.2 for the A/A genotype) and in the uSpA subgroup (pC<0.05, OR=3.8 for the A allele and pC<0.05, OR=4.3 for the A/A genotype). CONCLUSION: In addition to the association of SpA with HLA-B27, there is a significant association of HSP70-2 and HSP70-hom alleles with SpA in Mexicans. This association seems to be independent of the susceptibility conferred by HLA-B27 in the group of patients with uSpA.

Comparison of two schedules for administering oral low-dose methotrexate (weekly versus every-other-week) in patients with rheumatoid arthritis in remission: a twenty-four week, single blind, randomized study.

OBJECTIVE: To compare the efficacy of 2 low-dose oral methotrexate (MTX) schedules in maintaining remission in patients with rheumatoid arthritis (RA). METHODS: Patients with RA were included if they were receiving treatment with weekly MTX for at least 9 months and the RA was in remission (defined by American College of Rheumatology [ACR] criteria) for at least 6 months. Patients were stratified by treatment and randomly assigned to weekly or every-other-weekly (EOW; reducing their monthly dose by half) treatment with MTX. Patients were evaluated by a rheumatologist (blinded to the treatment schedule) at baseline and at 6, 12, and 24 weeks. The evaluations included joint counts, Ritchie Articular Index, Health Assessment Questionnaire Disability Index, physician's and patient's global health assessments, visual analog scale for pain, and incidence of adverse effects. Laboratory evaluations were done at baseline and at week 24. RESULTS: Fifty-one patients were included (26 taking weekly MTX, 25 taking EOW MTX). Baseline comparisons showed no differences between the groups. The mean duration of RA was <3 years in both groups, and they had been started on weekly MTX treatment early after diagnosis. After 24 weeks, >90% of the patients in both groups continued in remission. Evaluations of disease activity at 6 and 12 weeks showed no between-group differences. EOW MTX patients who experienced relapse were switched back to weekly MTX, and after a few weeks, their RA was again controlled. The incidence of adverse effects was slightly higher in the weekly MTX group, although the difference did not reach statistical significance. The observed laboratory values were very similar for both groups, except for the serum aspartate aminotransferase and alanine aminotransferase levels, which decreased in the EOW MTX group and were statistically significant at week 24 (P = 0.04 and P = 0.006, respectively). CONCLUSION: EOW MTX represents a valid therapeutic alternative for a specific subgroup of RA patients, as outlined by the ACR remission criteria. Patients with a short disease duration who were treated early after disease onset with weekly MTX and who achieve sustained remission have a higher probability of success with the EOW MTX schedule.

[Nasal provocation tests: dose-response relationship during D. pteronyssinus challenge]. / Test de provocación nasal: relación dosis-respuesta frente al D. pteronyssinus.

They are communicated the results of a study of the obtained responses as compared to D. pteronyssinus in function of the mcg/ml of antigen contents in an extract in the one which was characterized and quantified the allergen greater than represents 42% of the extracts. The interrelation analysis dose-response offers a value of r = 0.835, with a meaning level of 99% and the up spacing +/-28. The found regression equation was y = 0.235 x 9.047.

Estudio de los alergenos en el asma y rinitis de los panaderos / allergens in asthma and rhinitis of bakers

Mediante técnicas "in vitro" (RAST, RAST inhibición, RAST adsorción, RAST absorción) hemos analizado el papel de la harina de trigo y centeno. De los ácaros D. Farinae, L. Destructor y T. putrescens, así como el saccharomyces, Alternaria y de los parásitos Terebrio y Ephesia, en la génesis del asma y rinitis de los panaderos, hallamos que la harina de trigo es el antígeno más específico