Evidence of spatial clustering of childhood acute lymphoblastic leukemia cases in Greater Mexico City: report from the Mexican Inter-Institutional Group for the identification of the causes of childhood leukemia.

Background: A heterogeneous geographic distribution of childhood acute lymphoblastic leukemia (ALL) cases has been described, possibly, related to the presence of different environmental factors. The aim of the present study was to explore the geographical distribution of childhood ALL cases in Greater Mexico City (GMC). Methods: A population-based case-control study was conducted. Children <18 years old, newly diagnosed with ALL and residents of GMC were included. Controls were patients without leukemia recruited from second-level public hospitals, frequency-matched by sex, age, and health institution with the cases. The residence address where the patients lived during the last year before diagnosis (cases) or the interview (controls) was used for geolocation. Kulldorff's spatial scan statistic was used to detect spatial clusters (SCs). Relative risks (RR), associated p-value and number of cases included for each cluster were obtained. Results: A total of 1054 cases with ALL were analyzed. Of these, 408 (38.7%) were distributed across eight SCs detected. A relative risk of 1.61 (p<0.0001) was observed for the main cluster. Similar results were noted for the remaining seven ones. Additionally, a proximity between SCs, electrical installations and petrochemical facilities was observed. Conclusions: The identification of SCs in certain regions of GMC suggest the possible role of environmental factors in the etiology of childhood ALL.

Modelling the Unidentified Abortion Burden from Four Infectious Pathogenic Microorganisms (Leptospira interrogans, Brucella abortus, Brucella ovis, and Chlamydia abortus) in Ewes Based on Artificial Neural Networks Approach: The Epidemiological Basis for a Control Policy.

Unidentified abortion, of which leptospirosis, brucellosis, and ovine enzootic abortion are important factors, is the main cause of disease spread between animals and humans in all agricultural systems in most developing countries. Although there are well-defined risk factors for these diseases, these characteristics do not represent the prevalence of the disease in different regions. This study predicts the unidentified abortion burden from multi-microorganisms in ewes based on an artificial neural networks approach and the GLM. METHODS: A two-stage cluster survey design was conducted to estimate the seroprevalence of abortifacient microorganisms and to identify putative factors of infectious abortion. RESULTS: The overall seroprevalence of Brucella was 70.7%, while Leptospira spp. was 55.2%, C. abortus was 21.9%, and B. ovis was 7.4%. Serological detection with four abortion-causing microorganisms was determined only in 0.87% of sheep sampled. The best GLM is integrated via serological detection of serovar Hardjo and Brucella ovis in animals of the slopes with elevation between 2600 and 2800 meters above sea level from the municipality of Xalatlaco. Other covariates included in the GLM, such as the sheep pen built with materials of metal grids and untreated wood, dirt and concrete floors, bed of straw, and the well water supply were also remained independently associated with infectious abortion. Approximately 80% of those respondents did not wear gloves or masks to prevent the transmission of the abortifacient zoonotic microorganisms. CONCLUSIONS: Sensitizing stakeholders on good agricultural practices could improve public health surveillance. Further studies on the effect of animal-human transmission in such a setting is worthwhile to further support the One Health initiative.

Acute Phase Proteins in Dogs with Natural Infection by Trypanosoma cruzi.

Acute phase proteins have been used as tools for the diagnosis, monitoring, and prognosis of several diseases in domestic animals. However, the dynamics of these proteins in infection by Trypanosoma cruzi, the causative agent of Chagas disease in dogs, is still unknown. The aim of this study was to determine concentrations of acute phase proteins (C-reactive protein, haptoglobin, ferritin and paraoxonase-1) in dogs in a coastal town of Ecuador, with natural Trypanosoma cruzi infection with or without seroreactivity of Ehrlichia canis, Ehrlichia ewingii, Anaplasma phagocytophilum, Anaplasma platys, Borrelia burgdorferi and Dirofilaria immitis. For the detection of Trypanosoma cruzi serum antibodies, two different antigen-based enzyme-linked immunosorbent assay tests were implemented. For the detection of seroreactivity of Ehrlichia canis, Ehrlichia ewingii, Anaplasma phagocytophilum, Anaplasma platys, Borrelia burgdorferi and Dirofilaria immitis, an IDEXX SNAP® 4Dx® test was used. To determine the concentration of C-reactive protein and ferritin, an immunoturbidimetric assay was used; haptoglobin concentration was measured using a commercial colorimetric method validated in dogs; a spectrophotometric method was used to determine the serum concentration of paraoxonase-1. Results showed a reduction in the serum levels of paraoxonase-1 in Trypanosoma cruzi-seroreactive dogs, either with or without seroreactivity to other vector-borne diseases. A serum ferritin increment was observed in Trypanosoma cruzi-seroreactive dogs with seroreactivity to any other vector-borne diseases. Our findings suggest that paraoxonase-1 levels are reduced in Trypanosoma cruzi-seroreactive dogs without evident clinical signs of Chagas disease, despite their seroreactivity to the other vector-borne diseases studied. These findings could indicate an oxidative stress response in Trypanosoma cruzi-seroreactive dogs with no evident signs of inflammation.

Bioinformatic Approach of B and T Cell Epitopes of PLD and CP40 Proteins of Corynebacterium pseudotuberculosis ovis Mexican Isolate 2J-L towards a Peptide-Based Vaccine.

Mapping B and T cell epitopes constitutes an important action for peptide vaccine design. PLD and CP40 virulence factors of Corynebacterium pseudotuberculosis biovar ovis, a causal agent of Caseous Lymphadenitis, have been evaluated in a murine model as good candidates for vaccine development. Therefore, the goal of this work was to in silico analyze B and T cell epitopes of the PLD and CP40 proteins of a Mexican isolate of Corynebacterium pseudotuberculosis ovis. The Immune Epitope Data Base and Resource website was employed to predict the linear and conformational B-cell, T CD4+, and T CD8+ epitopes of PLD and CP40 proteins of Corynebacterium pseudotuberculosis ovis Mexican strain 2J-L. Fifty B cell epitopes for PLD 2J-L and forty-seven for CP40 2J-L were estimated. In addition, T CD4+ and CD8+ cell epitopes were predicted for PLD 2J-L (MHC I:16 epitopes, MHC II:10 epitopes) and CP40 2J-L (MHC I: 15 epitopes, MHC II: 13 epitopes). This study provides epitopes, paying particular attention to sequences selected by different predictor programs and overlap sequences as B and T cell epitopes. PLD 2J-L and CP40 2J-L protein epitopes may aid in the design of a promising peptide-based vaccine against Caseous Lymphadenitis in Mexico.

The Use of Peptides in Veterinary Serodiagnosis of Infectious Diseases: A Review.

Peptides constitute an alternative and interesting option to develop treatments, vaccines, and diagnostic tools as they demonstrate their scope in several health aspects; as proof of this, commercial peptides for humans and animals are available on the market and used daily. This review aimed to know the role of peptides in the field of veterinary diagnosis, and include peptide-based enzyme-linked immunosorbent assay (pELISA), lateral flow devices, and peptide latex agglutination tests that have been developed to detect several pathogens including viruses and bacteria of health and production relevance in domestic animals. Studies in cattle, small ruminants, dogs, cats, poultry, horses, and even aquatic organisms were reviewed. Different studies showed good levels of sensitivity and specificity against their target, moreover, comparisons with commercial kits and official tests were performed which allowed appraising their performance. Chemical synthesis, recombinant DNA technology, and enzymatic synthesis were reviewed as well as their advantages and drawbacks. In addition, we discussed the intrinsic limitations such as the small size or affinity to polystyrene membrane and mention several strategies to overcome these problems. The use of peptides will increase in the coming years and their utility for diagnostic purposes in animals must be evaluated.

Evaluación higiénico-sanitaria de restaurantes vinculados a la actividad turística / Hygienic-sanitary evaluation of restaurants linked to tourist activity

RESUMEN Introducción: en los servicios gastronómicos, la garantía higiénico-sanitaria es vital para su funcionamiento, dada la incidencia directa en la salud de los consumidores. Objetivo: diagnosticar la situación higiénico-sanitaria de restaurantes asociados a la actividad turística en el balneario de Varadero. Materiales y métodos: se evaluaron 33 restaurantes en operación, mediante 10 dimensiones compuestas por 116 indicadores, integrados en el Índice Global de Cumplimiento de los Prerrequisitos Sanitarios. La valoración del cumplimiento por dimensiones se llevó a cabo mediante la matriz importancia-cumplimiento, identificándose por el método combinatorio la existencia de clústeres. Se estableció la relación de los resultados con la capacitación de los recursos humanos y la forma de administración de las entidades. Resultados: se evidenció un elevado cumplimiento de los indicadores evaluados (87 %). Aunque se hallaron deficiencias higiénico-sanitarias en un alto porcentaje de restaurantes, el 67 % requiere de una atención inmediata. Se determinó una relación moderadamente fuerte entre el nivel de gestión de la inocuidad, la capacitación de los recursos humanos y la forma de gestión. Conclusiones: las dimensiones almacenamiento en seco y abastecimiento de agua presentaron un comportamiento adecuado. Las mayores deficiencias se asociaron a las dimensiones control de vectores, elaboración de alimentos y mantenimiento. Son necesarios la capacitación del personal vinculado a la actividad gastronómica y el incremento, en el sector privado, de las inspecciones sanitarias con un mínimo de requisitos predefinidos que avalen la operación gastronómica (AU).

ABSTRACT Introduction: the hygiene-sanitary guarantee is vital for the functioning of the gastronomic services, given the direct impact on the health of consumers. Objective: to diagnose the hygienic-sanitary situation of restaurants associated with tourist activity at Varadero resort. Materials and methods: 33 restaurants in operation were evaluated, using 10 dimensions composed of 116 indicators, integrated in the Global Index of Compliance with Health Prerequisites. The assessment of compliance by dimensions was carried out using the importance-compliance matrix, identifying the existence of clusters by the combinatorial method. The relationship of results with human resources training and entity management was established. Results: it was evidenced high compliance with the indicators assessed (87%). Although hygienic-sanitary deficiencies were found in a high percentage of restaurants, 67% of them, require immediate attention. A moderately strong relationship was identified between the level of food safety management, the training of human resources and the form of management. Conclusions: the dry storage and water supply dimensions had an adequate performance. The greatest deficiencies were associated with vector control, food processing and maintenance dimensions. The training of the staff linked to gastronomic activity is necessary and also the increase, in the private sector, of health inspections with a minimum of predefined requirements that endorse the gastronomic operation (AU).

Trypanosoma cruzi co-infections with other vector borne diseases are frequent in dogs from the pacific coast of Ecuador.

Dogs are a reservoir for Chagas disease, caused by Trypanosoma cruzi (T. cruzi), and other companion vector-borne diseases, including ehrlichiosis (Ehrlichia canis and Ehrlichia ewingii), anaplasmosis (Anaplasma phagocytophilum and Anaplasma platys), dirofilariasis (Dirofilaria immitis) and Lyme disease (Borrelia burgdorferi). This study has two key objectives: 1) to determine seroreactivity against T. cruzi in dogs from the town of Colón, in Portoviejo city, in the central coast of Ecuador; and 2) to establish the coinfection frequency of other companion vector-borne diseases in dogs positive for T. cruzi. Antibodies against T. cruzi were detected using two enzyme-linked immunosorbent assays. Diagnostic consensus between ELISA tests was established using the Cohen's Kappa coefficient. Other haemoparasitic diseases were detected using the IDEXX SNAP® 4Dx® kit in dogs previously diagnosed as T. cruzi-seropositive. From 84 dogs sampled, 57.14% (48/84) tested positive for T. cruzi. Co-infection analysis of 25 dogs positive for T. cruzi revealed antibodies also against Ehrlichia spp. (48%), Anaplasma spp. (28%), and Dirofilaria immitis (12%). These results provide a novel perspective regarding the status of these pathogens which co-infect dogs in Colón. Since all these pathogens are zoonotic, our findings should warn regional health authorities to implement sanitary programs, to better prevent and control vectors associated to these pathogens. On the other hand, human and veterinarian doctors, should consider that patients with a cardiac infection condition could be suffering co-infections with two or more vector transmitted pathogens.

Evaluation of Equine Infectious Anemia Virus by the Indirect Enzyme-linked Immunosorbent Assay EIA-LAB as Screening Tools in Mexico.

Equine infectious anemia is a worldwide distributed disease that affects the Equide family. Commercial effective vaccine is not available, for that reason control of the disease depends on diagnostic tools. To improve the efficiency of the diagnostic program in Cuba, LABIOFAM Group, developed an indirect enzyme-linked immunosorbent assay (ELISA), ELISA kit, to complement the diagnostic system that currently uses the agar gel immunodiffusion (AGID) kit. The ELISA AIE-LAB Kit was evaluated in a Mexican context, compared with the gold standard test Agar gel immunodiffusion, AGID AIE-LABIOFAM, and commercial AGID kit. The analytical sensitivity was determined using serial dilutions twofold of the positive control serum to establish the range of detected antibodies in relation to the cutoff value of the plate (OD 0.300). A precision study was carried out to evaluate repeatability, intermediate precision, and reproducibility by estimating the standard deviation and coefficient of variation. The precision results were satisfactory and the values of the coefficient of variation were considered adequate to guarantee an excellent consistency of the ELISA AIE-LAB. The diagnostic performance of the ELISA AIE-LAB involved the evaluation of specificity, sensitivity, and concordance in comparison with both AGID tests. The diagnostic sensitivity was 100% and the specificity 97.6%, with a very good degree of concordance (Kappa = 0.9). The results suggest that the ELISA AIE-LAB test could be used in Mexico as a diagnostic system for the detection of specific antibodies against the equine infectious anemia virus, as per current international norms.

Maternal and paternal ages at conception of index child and risk of childhood acute leukaemia: A multicentre case-control study in Greater Mexico City.

BACKGROUND: The parental age at conception has been reported to be a risk factor for childhood acute leukaemia (AL); however, the relationship is controversial. The aim of the present study was to investigate the association between parental age at conception and the risk of AL in Mexican children, a population with a high incidence of the disease and a high prevalence of pregnancies in adolescents and young adults. METHODS: A multicentre case-control study was conducted. Incident AL cases younger than 17 years of age diagnosed between 2010 and 2015 were included. Controls were matched with cases according to age, sex, and health institution. Using logistic regression analysis, adjusted odds ratios (aOR) and 95 % confidence intervals (95 % CI) were calculated for each maternal stratum after adjusting for paternal age at conception of index child. The maternal age between 25 and 29.99 years was selected as the reference category. RESULTS: In most strata where maternal and paternal ages were assessed, no association was found with the risk of developing acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML) in their offspring. An increased risk for AML was observed when the mother was between 20 and 24.99 years of age and the father aged 25-29.99 years (aOR, 1.94; 95 % CI, 1.03-3.67). In addition, there was a positive association for ALL when the mother´s age was between 20 and 24.99 years and the father was <20 years of age, however, a very wide confidence interval was noted (aOR, 12.26; 95 % CI, 1.41-106.83). CONCLUSION: In the present study, maternal and paternal ages assessed in different strata showed little association with risk of developing ALL and AML in children. Positive associations between risk of both types of childhood AL were observed with younger paternal and maternal ages.

Climbing the ladder of decline: Income and acculturation associated with chronic inflammation among Mexican immigrants.

OBJECTIVES: Financial hardship and immigrant status are often associated with poorer health as immigrant groups acculturate to life in the US. Known as the Latino health paradox, studies have shown that Latino/a immigrants in particular often experience declines in health the more they embrace ways of life considered "dominant" by US society. At present, critical biological pathways linking socioeconomic and acculturative processes remain to be better explained. The present study investigates associations among financial strain, acculturation, and chronic inflammation. METHODS: In our study of 129 Mexican-born immigrants living in the US, we used Pearson's correlations and multiple regression analyses to investigate links among income-to-poverty ratio (an indicator of financial strain), English language engagement (acculturation), and C-reactive protein (CRP), a measure of systemic inflammation. RESULTS: Results showed that for men, but not women, acculturation as defined by English language engagement moderated the association between an income-to-poverty ratio and CRP levels. CONCLUSIONS: Consistent with the Latino health paradox, more acculturated men with relatively higher income levels (compared with the study sample) had significantly higher levels of CRP.

Molecular Characterization of Trypanosoma cruzi in Infected Meccus pallidipennis in the Southern Region of the State of Mexico, Mexico.

PCR amplification and sequencing of Trypanosoma cruzi (T. cruzi) spliced-leader intergenic region of the mini-exon gene intergenic region (SL-IR) fragment was performed on intestinal tissue and fecal content DNA extracted from 19 Meccus pallidipennis (M. pallidipennis) specimens collected in the southern region of the State of Mexico. DNA sequence analysis from 49 bp T. cruzi SL-IR showed that all 19 samples corresponded to haplotype TcIa, and all of them were identical to GenBank sequence JQ028863. When extending the analysis to the whole 256 bp amplified sequence of the SL-IR, we found six sequences with a C insertion at position 10, one of which also presented a mutation (T/C) at position 54. One more sequence had an insertion (T) at position 223. Our findings suggest that two dominating TcIa clones are present in M. pallidipennis in the southern region of the State of Mexico. Interestingly, the SL-IR region of the dominating genotype was 100% identical to a circulating clone from Costa Rica present in humans, dogs, Triatoma dimidiata, and Panstrongylus rufotuberculatus. Future regional studies should explore the presence of this haplotype in humans and domestic animals.

Analysis of Surface Extraction Methods Based on Gradient Operators for Computed Tomography in Metrology Applications.

Among the multiple factors influencing the accuracy of Computed Tomography measurements, the surface extraction process is a significant contributor. The location of the surface for metrological applications is generally based on the definition of a gray value as a characteristic of similarity to define the regions of interest. A different approach is to perform the detection or location of the surface based on the discontinuity or gradient. In this paper, an adapted 3D Deriche algorithm based on gradient information is presented and compared with a previously developed adapted Canny algorithm for different surface types. Both algorithms have been applied to nine calibrated workpieces with different geometries and materials. Both the systematic error and measurement uncertainty have been determined. The results show a significant reduction of the deviations obtained with the Deriche-based algorithm in the dimensions defined by flat surfaces.

Association between IL-15 and insulin plasmatic concentrations in patients with pulmonary tuberculosis and type 2 diabetes.

IL-15 is part of the immune response in pulmonary tuberculosis (PTB) but amazingly, it may also induce physiological effects similar to those of insulin. We evaluated the IL-15 and insulin plasmatic levels in adults with PTB and with or without type 2 diabetes mellitus (DM2), who received previous antituberculosis therapy for at least 2 months. We analyzed the concentrations of glucose, glycated hemoglobin, insulin, as well as levels of IL-15, IL-2, IFN-γ, and TNF-α in patients with PTB, patients with PTB-DM2, household contacts with DM2 (C-DM2), and healthy household contacts (H-C). Our results showed unexpected high levels of glucose, insulin, and IL-15 in the PTB and C-DM2 groups. In comparison, low levels of these same indicators were observed in the PTB-DM2 and H-C groups. Interestingly, our analysis showed a positive correlation of IL-15 with insulin in the PTB group (r = 0.73) and in the C-DM2 group (r = 0.66). In comparison, a weak correlation between IL-15 and insulin was observed in the PTB-DM group (r = 0.10) and in the H-C group (ρ = 0.26). Our results suggest an association between IL-15 and insulin levels in the patient with PTB. Intriguingly, this association was weaker in the patient with PTB-DM2.

Retrospective analysis of skin complications related to bone-anchored hearing aid implant: association with surgical technique, quality of life, and audiological benefit / Análise retrospectiva de complicações cutâneas relacionadas ao implante de prótese auditiva óssea: associação com técnica cirúrgica, qualidade de vida e benefício audiológico

Abstract Introduction: The bone-anchored hearing aid is an effective form of auditory rehabilitation. Due to the nature of the implant, the most common complications are skin related. A number of alternative surgical implantation techniques have been used to reduce the frequency and severity of skin complications, including the U-shaped graft and the linear incision. Objective: To assess skin complications and their association with surgical technique, quality of life, and audiological benefit in patients with bone-anchored hearing aids. Methods: This was a retrospective study conducted in a tertiary referral center in Bogotá, Colombia. Patients who had been fitted with a bone-anchored hearing aid implant (unilaterally or bilaterally) for at least 6 months were included in the study. The Holgers classification was used to classify skin complications (Grade 0 = none; Grade 1 = erythema; Grade 2 = erythema and discharge; Grade 3 = granulation tissue; and Grade 4 = inflammation/infection resulting in the removal of the abutment). The Glasgow Benefit Inventory questionnaire was used to determine quality of life, and the Abbreviated Profile of Hearing Aid Benefit questionnaire was used to determine the subjective audiological benefit. Results: A total of 37 patients were included in the study (30 with unilateral implants and 7 with bilateral implant). Of the 44 implants evaluated, 31 (70.3%) were associated with skin complications (7 [15.9%] Grade 1; 4 [9.1%] Grade 2; 15 [34.1%] Grade 3, 5 [11.4%] Grade 4). The U-shaped graft was statistically associated with major complications (Grades 3 and 4) compared with the linear incision technique (p = 0.045). No statistically significant differences were found between Abbreviated Profile of Hearing Aid Benefit scores and severity of complications. Similarly, no differences were found between Glasgow Benefit Inventory physical health questions and skin complications. Conclusion: Despite the high frequency, skin complications did not seem to affect quality of life or subjective audiological benefits of patients with bone-anchored hearing aids.

Resumo Introdução: A prótese auditiva óssea (BAHA, do inglês Bone-Anchored Hearing Aid) é uma forma eficaz de reabilitação auditiva. Devido à natureza do implante, as complicações mais comuns são relacionadas à pele. Várias técnicas opcionais de implantação cirúrgica têm sido usadas para reduzir a frequência e a gravidade das complicações cutâneas, inclusive o enxerto em forma de U e a incisão linear. Objetivo: Avaliar as complicações cutâneas e sua associação com a técnica cirúrgica, qualidade de vida e benefício audiológico em pacientes com BAHAs. Método: Estudo retrospectivo feito em um centro terciário de referência em Bogotá, Colômbia. Os pacientes que receberam um implante de BAHA (unilateral ou bilateralmente) durante pelo menos seis meses foram incluídos no estudo. A classificação de Holgers foi usada para classificar as complicações cutâneas (Grau 0 = nenhuma, Grau 1 = eritema, Grau 2 = eritema e secreção, Grau 3 = tecido de granulação e Grau 4 = inflamação/infecção, resultou na remoção da estrutura de apoio). O questionário Glasgow Benefit Inventory (GBI) foi usado para determinar a qualidade de vida e o questionário Abbreviated Profile of Hearing Aid Benefit (APHAB) foi usado para determinar o benefício audiológico subjetivo. Resultados: Foram incluídos 37 pacientes (30 com implantes unilaterais e sete com implantes bilaterais). Dos 44 implantes avaliados, 31 (70,3%) foram associados às complicações cutâneas (sete [15,9%] Grau 1; quatro [9,1%] Grau 2; 15 [34,1%] Grau 3 e cinco [11,4%] Grau 4). O enxerto em forma de U foi estatisticamente associado a complicações maiores (Graus 3 e 4) em comparação com a técnica de incisão linear (p = 0,045). Não foram encontradas diferenças estatisticamente significativas entre os escores APHAB e gravidade das complicações. Do mesmo modo, não foram encontradas diferenças entre as questões de saúde física pelo questionário GBI e complicações cutâneas. Conclusão: Apesar da alta frequência, as complicações cutâneas não parecem afetar a qualidade de vida ou os benefícios audiológicos subjetivos de pacientes com BAHAs.

Phylogenetic relationship of Ornithobacterium rhinotracheale strains.

The bacterium Ornithobacterium rhinotracheale is associated with respiratory disease in wild birds and poultry. In this study, the phylogenetic analysis of nine reference strains of O. rhinotracheale belonging to serovars A to I, and eight Mexican isolates belonging to serovar A, was performed. The analysis was extended to include sequences from another 23 strains available in the public domain. The analysis showed that the 40 sequences formed six clusters, I to VI. All eight Mexican field isolates were placed in cluster I. One of the reference strains appears to present genetic diversity not previously recognized and was placed in a new genetic cluster. In conclusion, the phylogenetic analysis of O. rhinotracheale strains, based on the 16S rRNA gene, is a suitable tool for epidemiologic studies.

A greater birthweight increases the risk of acute leukemias in Mexican children-experience from the Mexican Interinstitutional Group for the Identification of the Causes of Childhood Leukemia (MIGICCL).

In Mexico, due to the high rates of diabetes, overweight, and obesity, there has also been noted an increased newborn weight, which may be contributing to the elevated incidence rate of childhood acute leukemia (AL). We conducted a case-control study in public hospitals of Mexico City aimed to know whether a greater weight at birth is associated with a higher risk of developing leukemia. We included incident cases with acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) diagnosed between 2010 and 2015. Controls were frequency-matched to the cases by age, sex, and health institution. Logistic regression analysis was performed adjusting risks by child's sex, overcrowding index, birth order, and mother's age at the time of pregnancy. Adjusted odds ratios (aORs) and 95% confidence intervals were calculated. A total of 1455 cases and 1455 controls were included. An evident association between ALL and child's birthweight ≥2500 g was found (aOR 2.06; 95% CI: 1.59, 2.66) and also, in those with birthweight ≥3500 g (aOR 1.19; 95% CI: 1.00, 1.41). In AML patients with birthweight ≥2500 g and ≥3500 g, an aOR of 1.77 (95% CI: 1.07, 2.94) and 1.42 (95% CI: 1.03-1.95) was observed, respectively. No association was noticed with either type of AL and a birthweight ≥4000 g. To sum up, we found a moderate association between not having a low birthweight and an increased risk of acute leukemias. Birthweight ≥3500 g was also a risk factor for both types of leukemia. This suggests that a greater birthweight may increase the risk of acute leukemias in Mexican children.

Isolation and molecular characterization of Corynebacterium pseudotuberculosis from sheep and goats in Mexico.

The pathogenic bacteria of Corynebacterium pseudotuberculosis caused a chronic contagious infectious disease of the caseous lymphadenitis or pseudotuberculosis. Globally, isolates obtained from different injuries that affect sheep and goats, have been identified by fully or partially gene sequencing. However, in Mexico there is no complete study to identify by molecular and phylogenetic techniques the circulating isolates as well as its virulence factors. Therefore, in the present study we reported the identification of 57 isolates of C. pseudotuberculosis by bacteriological tests and the amplification of 16S rRNA, rpoB and pld genes, as well as, genes involved in virulence and pathogenicity: Fag A, Fag B, Fag C, Fag D and hsp60. Phylogenetic analysis was performed based on the partial sequence of the rpoB gene. Genes involved in virulence and pathogenicity were identified in the 98.2% of the isolates. Regarding the phylogenetic analysis, were identified the species and subspecies to which they belong of all the tested isolates. The phenotypic and genotypic characterization will allow to establish preventive and prophylactic measures aimed to the creation of effective immunogens against Corynebacterium pseudotuberculosis.

Antibiotics susceptibility of quinolones against Salmonella spp. strains isolated and molecularly sequenced for gyrA gene.

Drug-resistant Salmonella is frequently detected in most parts of the world, and its rate of resistance has increased significantly in recent years. However, this study aimed to evaluate the minimum inhibitory concentration (MIC, determined with the Kirby-Bauer method) of quinolones in 86 Salmonella spp. strains isolated from pigs. Both the inside and outside of the QRDR region of strains were sequenced. The DNA sequence of the QRDR region of Salmonella spp. revealed the mutations S83F, D87N and S83Y. The region outside the QRDR showed a mutation in L582G. Forty-five isolates of Salmonella ssp. were categorized as quinolone-resistant; out of these, 16 corresponded to Salmonella enterica and isolates showed intermediate resistance (6.25%) to nalidixic acid. Three isolats (18.6%) were resistant to ampicillin; two (12.5%) were resistant to carbenicillin. Moreover, three (18.7%) isolates were resistant to gentamicin, nitrofurantoin and pefloxacin, and 8 (50%) were resistant to trimethoprim/sulfamethoxazole. Six percent of Salmonella spp. strains showed less resistance to antimicrobial agents compared to S. Thyphimurium (18%). The resistance to individual quinolones varied by serotypes. For S. anatum and S. Reading, it was 12.25%, and for S. choreaeaesuis, S. typhimurium monofasica, 6.25%. In contrast, S. agona, S. bredeney and S. london were sensitive to these antibiotics. In conclusion, quinolones have become the drugs of choice for the treatment of severe Salmonella infections. The study of mutations outside the QRDR region opens up new insights about the resistance of Salmonella to fluoroquinolones.

Retrospective analysis of skin complications related to bone-anchored hearing aid implant: association with surgical technique, quality of life, and audiological benefit.

INTRODUCTION: The bone-anchored hearing aid is an effective form of auditory rehabilitation. Due to the nature of the implant, the most common complications are skin related. A number of alternative surgical implantation techniques have been used to reduce the frequency and severity of skin complications, including the U-shaped graft and the linear incision. OBJECTIVE: To assess skin complications and their association with surgical technique, quality of life, and audiological benefit in patients with bone-anchored hearing aids. METHODS: This was a retrospective study conducted in a tertiary referral center in Bogotá, Colombia. Patients who had been fitted with a bone-anchored hearing aid implant (unilaterally or bilaterally) for at least 6 months were included in the study. The Holgers classification was used to classify skin complications (Grade 0=none; Grade 1=erythema; Grade 2=erythema and discharge; Grade 3=granulation tissue; and Grade 4=inflammation/infection resulting in the removal of the abutment). The Glasgow Benefit Inventory questionnaire was used to determine quality of life, and the Abbreviated Profile of Hearing Aid Benefit questionnaire was used to determine the subjective audiological benefit. RESULTS: A total of 37 patients were included in the study (30 with unilateral implants and 7 with bilateral implant). Of the 44 implants evaluated, 31 (70.3%) were associated with skin complications (7 [15.9%] Grade 1; 4 [9.1%] Grade 2; 15 [34.1%] Grade 3, 5 [11.4%] Grade 4). The U-shaped graft was statistically associated with major complications (Grades 3 and 4) compared with the linear incision technique (p=0.045). No statistically significant differences were found between Abbreviated Profile of Hearing Aid Benefit scores and severity of complications. Similarly, no differences were found between Glasgow Benefit Inventory physical health questions and skin complications. CONCLUSION: Despite the high frequency, skin complications did not seem to affect quality of life or subjective audiological benefits of patients with bone-anchored hearing aids.

Identification and molecular characterization of Corynebacterium xerosis isolated from a sheep cutaneous abscess: first case report in Mexico.

BACKGROUND: Corynebacterium xerosis is a commensal organism found in skin and mucous membranes of humans. It is considered an unusual pathogen, and it is rarely found in human and animal clinical samples. Here we describe the isolation of C. xerosis from a 4-months-old Pelifolk lamb located in Tesistán, central western Mexico. This microorganism should be considered for differential diagnosis in cutaneous abscessed lesions in sheep, as it represents a zoonotic risk factor for human infection in sheep farms. CASE PRESENTATION: The animal exhibited a hard-consistency, 5 cm diameter abscess, without drainage, in the neck. The presumptive clinical diagnosis was caseous lymphadenitis, caused by Corynebacterium pseudotuberculosis. Samples were obtained by puncture and cultured in 8 % sheep blood agar under microaerophilic conditions. Colonies were non-haemolytic, brown-yellowish and showed microscopic and biochemical features similar to C. pseudotuberculosis, except for the urea test. A multiplex-PCR for the amplification of partial sequences of the pld, rpoB and intergenic fragment from 16S to 23S genes suggested that isolate could be C. xerosis, which was later confirmed by sequencing analysis of the rpoB gene. CONCLUSIONS: This study shows for the first time isolation and molecular characterization of C. xerosis from a clinical sample of an ovine cutaneous abscess in Mexico. This finding highlights the need for differential diagnosis of this pathogen in ovine skin abscesses, as well as epidemiological and control studies of this pathogen in sheep farms.