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Cancer registries are essential for monitoring cancer burden and patterns, and document changes in time for cancer control. Hereby, we present the first results of four years of the Merida population-based cancer registry in Mexico.The registry collects data on all new cancers diagnosed since 2015 using both active and passive methods including a total of 104 information sources. Definitions and coding follow international standards. Using CanReg5 software, age-standardized incidence rates (ASR/100,000 person years) were computed by direct method using the world standard population.A total of 5684 new cancer cases were registered during 2015-2018, 2321 in males and 3363 in females corresponding to age-adjusted incidence rates (ASR per 100,000) of 128.5, and 153.1, respectively. Most frequent cancers among males were prostate cancer (ASR 29.8), lymphomas (ASR 10.9) and colorectal cancer (ASR 9.7) while among females it was breast cancer (ASR 49.3), cervical cancer (ASR 17.5) and corpus uteri (ASR 11.5). Childhood cancers (0-14 year) represented 2.9% of all cancers, with leukemias accounting for 52% of the new cases. Overall, 87.6% of new cases were microscopically verified.The data reported provide information on the cancer profile in Merida. Prostate and breast cancer are the main incident cancers. Cervical cancers present high rates among women, while lymphomas and liver cancer data merit further exploration. Efforts to support the Merida cancer registry as well as other registries in Mexico need to be pursued in order to have locally recorded data to support cancer control measures. more...

Breast cancer is a multifactorial and heterogeneous disease with distinct molecular features and histopathologic subtypes involving different therapeutic responses and clinical outcomes. Classification of breast cancer in molecular subtypes has made possible an approach to develop therapeutic strategies in order to have a better understanding of the breast cancer development. Due to the heterogeneity of the disease, there are still features to be elucidated in the behavior, etiology and clinical outcomes of each molecular subtype in breast cancer.Variables measured in 1,695 cases of invasive breast carcinoma were age, histopathological diagnosis, histopathological grade, expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER2), cell proliferation marker (Ki67) and basal cytokeratins (CK 5/6). P values were obtained using Chi square test and hazard ratios were calculated with 95% confidence intervals.An increase of aggressive molecular subtypes of breast cancer was observed. The mean age of incidence of breast cancer patients is decreasing, and breast cancer Patients younger than 40-years-old showed higher risk to exhibit Triple negative and Basal-like tumors.The mean age for this pathology is decreasing in our population and there is predominance in the differential occurrence of etiologically distinct entities of breast cancer affecting to the young women.El cáncer de mama es una enfermedad heterogénea y multifactorial. Presenta distintas características clínicas, moleculares e histopatológicas, las cuales se asocian con la respuesta a los esquemas terapéuticos, así como al resultado clínico. La clasificación en subtipos moleculares (luminales, HER2, triple negativo y basales) ha permitido el desarrollo y aplicación de estrategias terapéuticas particulares. Sin embargo, dada la gran heterogeneidad de la enfermedad, existen aún características por elucidar en el comportamiento, etiología y resultados clínicos de cada subtipo molecular de cáncer de mama.Se obtuvieron datos de 1695 casos de cáncer de mama invasor. Se realizaron correlaciones entre las siguientes variables: edad, diagnóstico histopatológico, grado histológico, expresión del receptor de estrógenos (ER), receptor de progesterona (PR), receptor 2 del factor de crecimiento epidérmico humano (HER2), marcador de proliferación celular (Ki67) y citoqueratinas basales (CK 5/6). Los valores deSe observó un incremento en la frecuencia de los subtipos moleculares más agresivos, así como una disminución en el valor de la media de la edad en las pacientes diagnosticadas con cáncer de mama. El análisis de la información indica que en pacientes menores de 40 años existe mayor riesgo a la presencia de tumores triple negativo o basales.En población mexicana, la media de edad para el diagnóstico primario de cáncer de está disminuyendo y hay mayor frecuencia de subtipos moleculares más agresivos en pacientes jóvenes. more...

Breast cancer is the most frequent malignancy in women around the world. Its diagnosis and treatment may be accompanied by depressive symptoms. The frequency of depression in women with breast cancer may vary, ranging from10% to70%, depending on the questionnaire, type of population studied and geographic area. Depression is associated with genetic and environmental factors; the imbalance between the central nervous, endocrine and immune systems; the patient’s age at diagnosis of cancer; metastasis; chemotherapy, and physical rehabilitation. Depression treatment is based on different types of approaches, such as hypnosis, meditation, music therapy and stress management. In Mexico, there are few studies about this topic. The objective of this work is to make a critical review on the scientific evidence of the relation between depression and breast cancer.El cáncer de mama es la neoplasia maligna más frecuente en mujeres en todo en el mundo. Su diagnóstico y tratamiento puede estar acompañado de síntomas depresivos. La frecuencia de depresión en mujeres con cáncer de mama puede ser tan variada que va desde10% a70%, dependiendo del instrumento de evaluación, el tipo de población estudiada y el área geográfica. Se ha descrito que la depresión se asocia a factores genético-ambientales; desequilibrio entre los sistemas nervioso central, endócrino e inmunitario; edad de la paciente; presencia de metastasis; quimioterapia, y rehabilitación física. Su tratamiento está basado en diversos tipos de abordajes, como hipnosis, meditación, musicoterapia y manejo del estrés. En México se ha estudiado poco esta relación. El objetivo de este trabajo es realizar una revisión crítica sobre la evidencia científica de la relación entre depresión y cáncer de mama. more...

Advances in the understanding of molecular biology of cancer have allowed that in the last 30 years some biomarkers in cancer have managed to be transferred from the laboratory to clinical practice and have been established as extremely important tools in the management of breast cancer patients. In this review are presented some biomarkers that are routinely used in clinical oncology practice and have a well-established clinical value to direct treatment and establish prognosis in patients with breast cancer, such as ER-alpha (estrogen receptor alpha), PR (progesterone receptor), HER2 (Human Epidermal Growth Factor Receptor 2), Ki-67 (Marker Of Proliferation Ki-67), and other biomarkers, such as multigenic signatures, which are used more and more frequently, due to the clinical value shown in various randomized clinical trials and for being increasingly accessible in daily clinical practice. Given the considerable importance of breast cancer in public health, it is necessary to be updated with respect to current biomarkers that have a use in clinical practice and that can serve as tools to provide patients with a more personalized treatment, as well as to know their prognosis.Los avances en el entendimiento de la biología molecular del cáncer han permitido que en los últimos 30 años algunos biomarcadores en cáncer hayan logrado ser trasladados del laboratorio a la práctica clínica y se hayan ido estableciendo como herramientas sumamente importantes en el manejo de las pacientes con cáncer de mama. En esta revisión se presentan algunos biomarcadores de uso rutinario en la práctica clínica oncológica que tienen un valor clínico bien establecido para dirigir el tratamiento y establecer el pronóstico en pacientes con cáncer de mama, como el ER-alfa (receptor de estrógenos alfa), el PR (receptor de progesterona), el HER2 (receptor 2 del factor de crecimiento epidérmico humano), el Ki-67 (marcador de proliferación Ki-67) y otros biomarcadores, como las firmas multigénicas, las cuales son usadas cada vez con más frecuencia, debido al valor clínico mostrado en diversos ensayos clínicos aleatorizados y por ser cada vez más accesibles en la práctica clínica diaria. Dada la considerable importancia del cáncer de mama en la salud pública, es necesario estar actualizados con respecto a estos biomarcadores de uso clínico, los cuales nos pueden permitir brindarles a las pacientes un tratamiento más personalizado, así como conocer su pronóstico. more...

Men develop gastric cancer more frequently than women, yet little is known about the mechanisms underlying this sex difference. Sex steroid hormones may influence gastric cancer risk. We therefore assessed whether major circulating adrenal precursors, androgens and estrogens were associated with gastric cancer in a high-risk Mexican population.Blood samples were collected at time of diagnosis from 50 noncardia gastric cancer patients and 50 histologically confirmed non-atrophic gastritis controls. Serum levels of estradiol, testosterone and dehydroepiandrosterone (DHEA) measured with a validated mass spectrometry method were categorized in tertiles as low (T1), middle (T2), and high (T3). Unconditional logistic regression models were used to calculate odds ratios (ORs) and 95% confidence intervals (CI), adjusting for age, sex, and education.Levels of DHEA were inversely associated with gastric cancer (p-trend per tertile increase:0.0001), with adjusted ORs (95% CI) of T2 and T3 (vs. T1) of 0.25 (0.09-0.70) and 0.10 (0.03-0.34), respectively. Levels of estradiol and testosterone were not significantly associated with gastric cancer.Our study provides evidence that higher concentration of circulating DHEA may be associated with lower risk of noncardia gastric cancer. Longitudinal studies are needed to evaluate the temporality of this association and investigate mechanisms of disease pathogenesis. more...

International audience; Background: Cervical cancer (CC) is associated to high-risk human papillomavirus (HPV) infections, for this reason it is crucial to have sensitive and accurate HPV diagnostic tests. To date, most research is focused on HPVs within the Alphapapillomavirus (α-PVs) genus and little attention has been paid to cervical infections with other HPV genotypes, like those of the Betapapillomavirus (β-PVs) and Gammapapillomavirus (γ-PVs) genera. The aim of this study was to determine the HPV genotypes from different genera in women with CC using Next-Generation Sequencing (NGS).Methods: The study comprised 48 HPV positive CC samples evaluated with the Linear Array HPV Genotyping test and individually sequenced by 454 NGS using PGMY09/11 and FAP primers. To determine the HPV genotypes present in each sample, the obtained sequences were compared with all HPV L1 gene reference sequences from the Papillomavirus Episteme database (PaVE). Moreover, 50 HPV positive low-grade cervical lesion samples individually genotyped with NGS were also included to determine the genotypes present preferentially in CC patients.Results: Among the 48 CC samples, 68.75% consisted of multiple HPV infections, 51 different genotypes were detected, of which 7 are still unclassified, 28 belong to α-PVs (6, 11, 16, 18, 26, 30, 33, 35, 39, 42, 43, 44, 45, 51, 52, 53, 54, 59, 62, 66, 68, 69, 70, 71, 74, 81, 102, 114), 10 to β-PVs (5, 12, 21, 37, 38b, 47, 80, 107, 118, 122), and 6 to γ-PVs (101, 103, 123, 135, 147, 214). Among them, HPV16 was the most prevalent genotype (54.2%), followed by HPV18 (16.7%), HPV38b (14.6%), and HPVs 52/62/80 (8.3%). Some genotypes were exclusively found in CC when compared with Cervical Intraepithelial Neoplasia grade 1 (CIN1) samples, such as HPVs 5, 18, 38b, 107, 122, FA39, FA116, mSK_120, and mSK_136.Conclusions: This work demonstrates the great diversity of HPV genotypes detected by combining PGMY and FAP primers with NGS in cervical swabs. The relatively high attribution of β- and γ- PVs in CC samples suggest their possible role as carcinogenic cofactors, but deeper studies need to be performed to determine if they have transforming properties and the significance of HPV-coinfections. more...

Antecedents: The serum levels of some cytokines can be useful in the diagnosis of neonatal sepsis; the prognostic value of a cytokine profile has not, to our knowledge, been explored in this diseas... more...

To briefly describe the process of establishment and preliminary results of the Mérida Population-based Cancer Registry (Mérida-PBCR).Mérida-PBCR started in 2016 as a research project in the IMSS, with a gradual increase in its information sources. It covers a population of 908 536 inhabitants. Data collection is active and passive, international standards are used; CanReg5 software enables data entry, storage and analysis.Current data include 71.5% of sources. For the period 2015- 2016, a total of 2 623 new cancer cases were registered, the majority of these (60.1%) among females. 81.5% of the cases had morphological verification. Prostate (17.4%), colorectal (8.5%) and stomach (8.1%) cancers were the most common among males, and breast (31.6%), cervix (12%) and corpus uteri (7.6%) cancers, the most common among females. Ageadjusted cancer incidence rates (per 100 000) for all sites combined were 114.9 among males and 145.1 among females.The implementation of the Mérida-PBCR has followed particular parameters, with important efforts to include new information sources. Although the data are still preliminary and must be interpreted with great caution, the main cancers follow a similar pattern to that of the national and regional estimates.Describir brevemente el proceso de implementación y resultados preliminares del Registro de Cáncer de Base Poblacional (RCBP) de Mérida.RCBP-Mérida inició en 2016 como un proyecto de investigación del IMSS, con cobertura poblacional de 908 536 habitantes. El número de fuentes de información ha incrementado gradualmente. Se realizó colección de datos de forma pasiva y activa en software CanReg5 utilizando estándares internacionales.Se han incluido al RCBP-Mérida 71.5% de las fuentes de información. Durante 2015-2016 se registraron 2 623 casos nuevos, la mayoría (60.1%) mujeres. El 81.5% de los casos tuvo verificación morfológica. En hombres, el cáncer de próstata (17.4%), colorrectal (8.5%) y estómago (8.1%) son los más comunes; en mujeres, mama (31.6%), cérvix (12.0%) y cuerpo-uterino (7.6%). Las tasas de incidencia ajustadas por edad (100 000 habitantes) para todos los sitios combinados son 114.9 hombres y 145.1 mujeres.La implementación del RCBP-Mérida ha seguido parámetros particulares, con importante esfuerzo para incluir fuentes de información. Aunque los datos son preliminares y se deben interpretar con precaución; los principales tipos de cáncer siguen un patrón similar a las estimaciones nacionales y regionales. more...

Cancer is one of the major causes of morbidity and mortality in the world, with 14.1 million new cases and 8.2 million deaths annually. A marked disparity exists between developed countries and developing countries, with 57% of new cases and 65% of deaths in 2012 occurring in developing countries. This global picture can only be obtained because of data obtained from population-based cancer registries, which allow cancer estimations for different geographic areas. Our objective is to perform a review of different types of registries and their role in the control of cancer. These types of registries are lacking in developing countries. In Central and South America, only 6% of the population is included in cancer registries versus 83% in North America. It is necessary to increase the coverage of cancer registries to obtain more reliable data that will more appropriately guide control programs. DOI: http://dx.doi.org/10.21149/spm.v58i2.7802 more...

Different lines of evidence support an association between Epstein-Barr virus (EBV) and gastric cancer (GC). The main understood risk factor to develop GC is infection by Helicobacter pylori (H. pylori), which triggers a local inflammatory response critical for progression from gastritis to GC. The role of EBV in early inflammatory gastric lesions has been poorly studied. A recent study proposed a cutoff value of 2000 EBV particles to identify patients with increased chances of infection of the gastric epithelium, which may favor the inflammatory process. To better understand the role of EBV in cancer progression, we analyzed 75 samples of GC, 147 control samples of non-tumor gastric tissue derived from GC patients and 75 biopsies from patients with non-atrophic gastritis (NAG). A first-round PCR was used for EBV detection in tumor and non-tumor controls and a more sensitive nested PCR for gastritis samples; both PCRs had lower detection limits above the proposed cutoff value. With this strategy 10.67% of GC, 1.3% of non-tumor controls and 8% of gastritis samples were found positive. An EBER1 in situ hybridization showed EBV infection of epithelial cells in GC and in a third of NAG samples, while in the other NAGs infection was restricted to the mononuclear cell infiltrate. EBV-positive GCs were enriched in lace and cribriform patterns, while these rare patterns were not observed in EBV negative samples. Our results support a role for EBV in GC and early precursor lesions, either as directly oncogenic infecting epithelial cells or indirectly as an inflammatory trigger. more...

Background Human papillomavirus (HPV) is the main etiological agent of cervical cancer, the third most common cancer among women globally and the second most frequent in Mexico. Persistent infection with high-risk HPV genotypes is associated with premalignant lesions and cervical cancer development. HPVs considered as low risk or not yet classified, are often found in coinfection with different HPV genotypes. Indeed, HPV62 is one of the most prevalent HPV detected in some countries, but there is limited information about its prevalence in other regions and there are no HPV62 variants currently described. The aim of this study was to determine the prevalence of HPV62 in cervical samples from Mexican women and to identify mutations in the L1, E6 and E7 genes, which have never been reported in our population. Methods HPV screening was performed by Cobas HPV Test in women who attended prevention health programs and dysplasia clinics. All HPV positive samples (n = 491) and 87 additional cervical cancer samples were then genotyped with Linear Array HPV Genotyping test. Some samples were selected to corroborate genotyping by Next-Generation sequencing. On the other hand, nucleotide changes in L1, E6 and E7 genes were determined using PCR, Sanger sequencing and analysis with the CLC-MainWorkbench 7.6.1 software. L1 protein structure was predicted with the I-TASSER server. Results Using Linear Array, HPV62 prevalence was 7.6% in general population, 8% in Cervical Intraepithelial Neoplasia grade 1 (CIN1) samples and 4.6% in cervical samples. The presence of HPV62 was confirmed with Next-Generation sequencing. Regarding L1 gene, novel sequence variations were detected, but they did not alter the tertiary structure of the protein. Moreover, several nucleotide substitutions were found in E6 and E7 genes compared to reference HPV62 genomic sequence. Specifically, three non-synonymous sequence variations were detected, two in E6 and one in E7. Conclusions HPV62 is a frequent HPV genotype found mainly in general population and in women with CIN1, and in 90.5% of the cases it was found in coinfection with other HPVs. Novel nucleotide changes in its L1, E6 and E7 genes were detected, some of them lead to changes in the protein sequence. more...

// Jone Garay 1 , M. Blanca Piazuelo 2 , Lizbeth Lopez-Carrillo 3 , Yelda A. Leal 4 , Sumana Majumdar 1 , Li Li 1 , Nataly Cruz-Rodriguez 1, 5, 6 , Silvia J. Serrano-Gomez 1, 5, 6 , Carlos S. Busso 7 , Barbara G. Schneider 2 , Alberto G. Delgado 2 , Luis E. Bravo 8 , Angela M. Crist 9 , Stryder M. Meadows 9 , M. Constanza Camargo 10 , Keith T. Wilson 2, 11 , Pelayo Correa 2 and Jovanny Zabaleta 1, 12 1 Stanley S. Scott Cancer Center, LSUHSC, New Orleans, LA, USA 2 Division of Gastroenterology, Hepatology, and Nutrition, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA 3 Instituto Nacional de Salud Publica, Cuernavaca, Morelos, Mexico 4 Unidad de Investigacion Medica Yucatan de la Unidad Medica de Alta Especialidad (UMAE) del Instituto Mexicano del Seguro Social (IMSS), Yucatan, Mexico 5 Pontificia Universidad Javeriana, Bogota, Colombia 6 Grupo de Investigacion en Biologia del Cancer, Instituto Nacional de Cancerologia, Bogota, Colombia 7 Department of Otorhinolaryngology, LSUHSC, New Orleans, LA, USA 8 Department of Pathology, Universidad del Valle, Cali, Colombia 9 Department of Cell and Molecular Biology Tulane University, New Orleans LA, USA 10 Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD, USA 11 Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN, USA 12 Department of Pediatrics, LSUHSC, New Orleans, LA, USA Correspondence to: Jovanny Zabaleta, email: jzabal@lsuhsc.edu Keywords: precancerous gastric lesions, DMBT1 , H. pylori , inflammation, gastric cancer Received: October 25, 2016 Accepted: March 16, 2017 Published: April 03, 2017 ABSTRACT Helicobacter pylori infection triggers a cascade of inflammatory stages that may lead to the appearance of non-atrophic gastritis, multifocal atrophic, intestinal metaplasia, dysplasia, and cancer. Deleted in malignant brain tumors 1 (DMBT1) belongs to the group of secreted scavenger receptor cysteine-rich proteins and is considered to be involved in host defense by binding to pathogens. Initial studies showed its deletion and loss of expression in a variety of tumors but the role of this gene in tumor development is not completely understood. Here, we examined the role of DMBT1 in gastric precancerous lesions in Caucasian, African American and Hispanic individuals as well as in the development of gastric pathology in a mouse model of H. pylori infection. We found that in 3 different populations, mucosal DMBT1 expression was significantly increased (2.5 fold) in individuals with dysplasia compared to multifocal atrophic gastritis without intestinal metaplasia; the increase was also observed in individuals with advanced gastritis and positive H. pylori infection. In our animal model, H. pylori infection of Dmbt1-/- mice resulted in significantly higher levels of gastritis, more extensive mucous metaplasia and reduced Il33 expression levels in the gastric mucosa compared to H. pylori -infected wild type mice. Our data in the animal model suggest that in response to H. pylori infection DMBT1 may mediate mucosal protection reducing the risk of developing gastric precancerous lesions. However, the increased expression in human gastric precancerous lesions points to a more complex role of DMBT1 in gastric carcinogenesis. more...

Background and Aims Childhood acute lymphoblastic leukemia (ALL) is the leading cause of childhood cancer-related deaths worldwide. Multiples studies have shown that ALL seems to be originated by an interaction between environmental and genetic susceptibility factors. The ARID5B polymorphisms are among the most reproducible ALL associated-risk alleles in different populations. The aim of the present study was to examine the contribution of ARID5B, CEBPE, and PIP4K2 risk alleles for the development of ALL in children from Mexico City and Yucatan, Mexico. Methods A study was conducted with a total of 761 unrelated subjects. Two hundred eighty five ALL cases (111 from Yucatan and 174 from Mexico City) and 476 healthy subjects. Genotyping included the rs7088318 ( PIP4K2A ), rs10821936 ( ARID5B ), rs7089424 ( ARID5B ) and rs2239633 ( CEBPE ) polymorphisms. Results Associations between ALL and rs10821936 and rs7089424 ARID5B SNPs were found (OR = 1.9, 95% CI (1.5–2.4) and OR = 2.0, 95% CI (1.6–2.5), respectively). Moreover, a higher risk was observed in the homozygous risk genotypes of carriers from Mexico City (OR = 3.1, 95% CI (2.0–4.9) and OR 3.1, CI 95% (2.0–4.8), respectively). Otherwise, the rs7088318 ( PIP4K2A ) and rs2239633 ( CEBPE ) polymorphisms were not associated with ALL risk. Conclusions Our analysis suggests that ARID5B confers risk for childhood ALL in a Mexican population. more...

Background and Aims It has been demonstrated that heterozygote and homozygote thiopurine S-methyltransferase ( TPMT ) mutant allele carriers are at high risk to develop severe and potentially fatal hematopoietic toxicity after treatment with standard doses of 6-mercaptopurine (6-MP) and methotrexate (MX). Those drugs are the backbone of acute lymphoblastic leukemia (ALL) and several autoimmune disease treatments. We undertook this study to determine the frequency of the TPMT deficient alleles in children with ALL and non-ALL subjects from Mexico City and Yucatan, Mexico. Methods We included 849 unrelated subjects, of which 368 ALL children and 342 non-ALL subjects were from Mexico City, and 60 ALL cases and 79 non-ALL individuals were from Yucatan. Genotyping of the rs1800462, rs1800460 and rs1142345 SNPs was performed by 5′exonuclease technique using TaqMan probes (Life Technologies Foster City, CA). Results The mutant TPMT alleles were present in 4.8% (81/1698 chromosomes) and only 0.2% were homozygote TPMT*3A/TPMT*3A . We did not find statistically significant differences in the distribution of the mutant alleles between patients from Mexico City and Yucatan in either ALL cases or non-ALL. Nonetheless, the TPMT*3C frequency in ALL patients was higher than non-ALL subjects ( p = 0.03). To note, the null homozygous TPMT*3A/TPMT*3A genotype was found in 2.5% of the non-ALL subjects. Conclusions TPMT mutant alleles did not exhibit differential distribution between both evaluated populations; however, TPMT*3C is overrepresented in ALL cases in comparison with non-ALL group. Assessing the TPMT mutant alleles could benefit the ALL children and those undergoing 6-MP and MX treatment. more...

The monocyte locomotion inhibitory factor (MLIF) is a heat-stable pentapeptide produced by Entamoeba histolytica in culture. This factor displays several anti-inflammatory properties ( i.e. , inhibition of locomotion and respiratory burst in monocytes, reduction of skin hypersensitivity and delay of mononuclear cells in human Rebuck skin windows) with inhibition of adhesion molecules, chemokines, and other genes including interleukin-1β (IL-1β). In animal models, it reduces carragenin-induced inflammation and delays the inflammatory process in murine collagen-induced arthritis (CIA). Objectives To test, in vitro , the anti-inflammatory capacity of MLIF on a promonocytic human cell line (U-937) cells and peripheral blood mononuclear cells (PBMC) from healthy subjects and from patients with rheumatoid arthritis (RA). Material and methods IL-1β gene expression was evaluated in cell cultures either in the presence of MLIF, lipopolysaccharide (LPS), or both. Relative gene expression and immunoreactivity of IL-1β were assayed in cells and supernatants, respectively. Results Amebic peptide was able to down-regulate LPS-induced expression of IL-1β, in U-937 cells without a detectable effect upon the bioavailability of the cytokine. In similar culture conditions, MLIF was capable to down-regulate baseline and LPS-induced expression of IL-β only in PBMC from patients with RA. Peptide effect on immunoreactivity of IL-1β was not statistically significant. Conclusions MLIF exerts, in primed cells, exquisite anti-inflammatory properties that deserve to be explored mechanistically. more...

Background: The 13C-urea breath test (13C-UBT) is a safe, noninvasive and reliable method for diagnosing H. pylori infection in adults. However, the test has shown variable accuracy in the pediatric population, especially in young children. We aimed to carry out a systematic review and meta-analysis to evaluate the performance of the 13C-UBT diagnostic test for H. pylori infection in children. Methods: We conducted a systematic review of the PubMed, Embase and Liliacs databases including studies from January 1998 to May 2009. Selection criteria included studies with at least 30 children and reporting the comparison of 13C-UBT against a gold standard for H. pylori diagnosis. Thirty-one articles and 135 studies were included for analysis. Children were stratified in subgroups of 6 years (sensitivity 96.6%, specificity 97.7%, LR+ 42.6, LR− 0.04, DOR 1042.7), 3, greater variability in accuracy estimates and on average a few percentage points lower, particularly specificity, in children ≤6 years (sensitivity 95%, specificity 93.5%, LR+ 11.7, LR− 0.12, DOR 224.8). Therefore, the meta-analysis shows that the 13C-UBT test is less accurate for the diagnosis of H. pylori infection in young children, but adjusting cutoff value, pretest meal, and urea dose, this accuracy can be improved. more...

Objective: Helicobacter pylori antigen or DNA in stool are meant to detect the bacteria; however, in children the colonization of the gastric mucosa by H pylori is usually weak and fecal excretion of antigen or DNA varies considerably, challenging the utility of these tests in this age group. The aim of the present study was to carry out a systematic review and meta-analysis to evaluate the performance of stool H pylori DNA and antigen tests for the diagnosis of infection in children. Methods: We conducted a systematic review and meta-analysis to assess the accuracy of stool tests for diagnosis of H pylori infection in children. We searched PubMed, EMBASE, and LILACS databases. Selection criteria included participation of at least 30 children and the use of a criterion standard for H pylori diagnosis. In a comprehensive search, we identified 48 studies. Results: Regarding antigen-detection tests, enzyme-linked immunosorbent assay (ELISA) monoclonal antibodies showed the best performance, with sensitivity and specificity of 97%, positive likelihood ratio (LR+) of 29.9, and negative likelihood ratio (LR-) of 0.03. ELISA polyclonal antibodies had sensitivity of 92%, specificity of 93%, LR+ of 16.2, LR- of 0.09, and high heterogeneity (P < 0.0001). One-step monoclonal antibody tests demonstrated sensitivity of 88%, specificity of 93%, LR+ of 10.6, and LR- of 0.11. For DNA detection, polymerase chain reaction-based test showed sensitivity of 80.8%, specificity of 98%, LR + of 17.1, and LR- of 0.18. Conclusions: Detection of H pylori antigen in stools with ELISA monoclonal antibodies is a noninvasive efficient test for diagnosis of infection in children. One-step tests showed low accuracy and more studies are needed to obtain a useful office-based screening test. The available molecular tests are still unreliable. more...

Monocyte locomotion inhibitory factor (MLIF), an amebic peptide with antiinflammatory properties, was evaluated in collagen-induced arthritis (CIA) to test its effects on the onset and acute inflammatory response of arthritis. DBA1/J mice at 8–10 weeks of age were divided into four groups (eight mice per group). The adjuvant group received Freund adjuvant, the CIA group was immunized with collagen II, the MLIF/CIA group received collagen II and MLIF, and the MLIF group received MLIF and Freund adjuvant. All groups were evaluated clinically. Seven weeks after the collagen injection, at the peak of the clinical arthritis score, limb specimens were collected and histological studies and gene expression analysis using microarrays were performed. MLIF administered weekly as a preventive scheme delayed and reduced the severity of acute arthritis. MLIF induced gene changes in functional categories including adhesion molecules, matrix metalloproteinases, and inflammatory cytokines. MLIF could be an interesting new molecule to investigate in the field of rheumatoid arthritis pathogenesis research for its potential to prevent inflammation. more...

Helicobacter pylori urease is required to counteract acidity during colonization of the stomach, and has been suggested as a major immunodominant antigen. The aim of this study was to determine the anti-urease response in a representative national serologic survey in Mexico. The population surveyed included persons 1-90 years of age from all socioeconomic levels and geographic zones of the country. Helicobacter pylori status was determined by ELISA serology. The IgG anti-urease was studied by ELISA using a recombinant apoenzyme. We found that 2,930 of the 7,720 infected patients (38%) were seropositive for IgG urease. The rate of IgG anti-urease positivity increased with age; in children10 years old it was20% and in persons40 years old it was50%. Age and a region with a high level of development were risk factors for seropositivity, whereas gender, educational level, crowding, and socioeconomic level were not associated with seropositivity. In conclusion, in natural infection with H. pylori, the response to urease is poor, mainly during the first years of infection. This inconsistent immune response to the enzyme may favor persistence of infection. A vaccine eliciting a consistent anti-urease response might overcome immune evasion and enhance clearance of bacteria after exposure. more...

Objective: Little is known about Helicobacter pylori infections and the immune response to urease and CagA in pediatric populations. Our aims were: 1) to validate serological assays for antibodies against whole cell extract, CagA, and urease of H. pylori; 2) to examine their role in diagnosis of infection in children with recurrent abdominal pain (RAP); and 3) to examine the antibody responses to CagA and urease in children. Methods: An enzyme-linked immunosorbent assay (ELISA) for diagnosis of H. pylori infection using whole cell extracts was validated in 50 children with biopsy-confirmed infection. The IgG and IgA antibody responses against recombinant CagA and urease were compared by ELISA in 82 children with RAP and in 246 age- and sex-matched healthy children. Results: The whole-cell extract ELISA had a sensitivity of 85% and specificity of 87%. Children with RAP were more infected with H. pylori than were healthy control subjects; however, IgG and IgA CagA seropositivity was lower among those with RAP than among asymptomatic children (34% and 23% vs 76% and 55%, respectively; p < 0.0001). In both groups of children, the immune response to urease was low. Conclusion: A serodiagnosis of H. pylori infection using native strains was developed. The difference in the immune response between children with RAP and control subjects suggests that RAP occurs during the acute phase of H. pylori infection. Our results also suggest that urease is a poor immunogen. more...

Breast cancer is the most frequent malignancy affecting women worldwide. It has been suggested that infection by Epstein Barr Virus (EBV), Mouse Mammary Tumor Virus or a similar virus, MMTV-like virus (MMTV-LV), play a role in the etiology of the disease. However, studies looking at the presence of these viruses in breast cancer have produced conflicting results, and this possible association remains controversial. Here, we used polymerase chain reaction assay to screen specific sequences of EBV and MMTV-LV in 86 tumor and 65 adjacent tissues from Mexican women with breast cancer. Neither tumor samples nor adjacent tissue were positive for either virus in a first round PCR and only 4 tumor samples were EBV positive by a more sensitive nested PCR. Considering the study's statistical power, these results do not support the involvement of EBV and MMTV-LV in the etiology of breast cancer. more...

The (13) C-urea breath test ((13) C-UBT) is a safe, noninvasive and reliable method for diagnosing H. pylori infection in adults. However, the test has shown variable accuracy in the pediatric population, especially in young children. We aimed to carry out a systematic review and meta-analysis to evaluate the performance of the (13) C-UBT diagnostic test for H. pylori infection in children.We conducted a systematic review of the PubMed, Embase and Liliacs databases including studies from January 1998 to May 2009. Selection criteria included studies with at least 30 children and reporting the comparison of (13) C-UBT against a gold standard for H. pylori diagnosis. Thirty-one articles and 135 studies were included for analysis. Children were stratified in subgroups of6 and ≥6 years of age, and we considered variables such as type of meal, cutoff value, tracer dose, and delta time for the analysis.The (13) C-UBT performance meta-analyses showed 1, good accuracy in all ages combined (sensitivity 95.9%, specificity 95.7%, LR+ 17.4, LR- 0.06, diagnostic odds ratio (DOR) 424.9), 2, high accuracy in children6 years (sensitivity 96.6%, specificity 97.7%, LR+ 42.6, LR- 0.04, DOR 1042.7), 3, greater variability in accuracy estimates and on average a few percentage points lower, particularly specificity, in children ≤6 years (sensitivity 95%, specificity 93.5%, LR+ 11.7, LR- 0.12, DOR 224.8). Therefore, the meta-analysis shows that the (13) C-UBT test is less accurate for the diagnosis of H. pylori infection in young children, but adjusting cutoff value, pretest meal, and urea dose, this accuracy can be improved. more...

Helicobacter pylori infection is one of the most common chronic infections in the world, and is acquired mainly during childhood. It is not clear to which extent a primary infection protects the child from reinfection. Our aim was to determine the possible protection conferred by a primary infection against H. pylori reinfection in children.A follow-up study with 120 children distributed in two cohorts; the first included 80 children without previous H. pylori infection (primo-infection cohort); the second included 40 infected children successfully eradicated (reinfection cohort). Cohorts were monitored during 2 years with urea-breath-test (UBT) at 3, 6, 9, 12, 18 and 24 months for the acquisition of H. pylori infection. We compared the rate of reinfection in eradicated children with the rate of infection in children without previous infection. H. pylori infection during the follow-up was analyzed and compared between cohorts using chi2 and survival curves. A questionnaire was performed for the evaluation of possible risk factors for infection in both cohorts.No significant differences in rates of primo-infection or reinfection were found; 17 (21.2%) primo-infections and 10 (25%) reinfections were documented. Most of the primo-infections (14/17) occurred in the first year of follow-up. In contrast, reinfection episodes occurred more frequently during the second year (6/10). In both cohorts, most infections were transient. Risk factors were similar for both, primo and reinfection cohorts.A primary infection does not protect from reinfection in the population of children studied. more...

Prevalence of antibodies against Giardia duodenalis was determined by enzyme-linked immunosorbent assay in serum samples from a national serologic survey of Mexico that included all geographic areas and socioeconomic and demographic data for each person sampled. The country was divided into four regions on the basis of development (high, medium high, medium low, and low). Of 3,461 serum samples tested, 1,914 (55.3%) were positive for IgG antibodies against Giardia duodenalis. Seropositivity was age-specific; the probability of seropositivity increased 4.9-fold (95% confidence interval [CI] = 3.16-7.64) in adolescents 10-19 years of age, 8.0-fold (95% CI = 5.19-12.53) in young adults 20-39 years of age, and 12.6-fold (95% CI = 7.93-20.28) in adults more than 40 years of age. Giardia duodenalis seropositivity was associated with male sex (odds ratio = 1.40, 95% CI = 1.22-1.61). No association was found between seropositivity and socioeconomic variables or regional development status. more...

Helicobacter pylori strains possessing the Cag pathogenicity island have been associated with increased gastric inflammation and with duodenal ulcer. In contrast, studies on the association of cagA+ H. pylori infections and gastric cancer have shown conflicting results. The aim of our study was to determine whether H. pylori and CagA status are associated with gastric cancer in Mexico. We selected serum samples from 3 geographic areas with gastric cancer mortality rates per 100,000 inhabitants of 2.5 (low risk), 4.5 (medium risk) and 6.4 (high risk). H. pylori infection was determined by the detection of antibodies to H. pylori whole cell antigen by an enzyme-linked immunosorbent assay (ELISA). To study the prevalence of infection with cagA+ strains, serum IgG antibodies to CagA were determined by ELISA using a recombinant CagA antigen. Of the 2,775 individuals studied, 1,931 were H. pylori seropositive and 1,710 had antibodies against CagA. The risk for gastric cancer in the 3 populations studied increased proportionally as infection with cagA+ strains increased (p < 0.001 for trend). H. pylori infection also showed association with gastric cancer (p < 0.05). Individuals seropositive for CagA, but seronegative for H. pylori whole cell antigen, were more frequent in areas with higher gastric cancer rates (p < 0.01). These results support the possible role of CagA(+) status as predictor of risk for gastric adenocarcinoma in Mexico; this is in agreement with results in European and American populations, but contrary to studies in some Asian countries. more...

A nationwide community-based survey for Helicobacter pylori infection had not been done. This study sought to determine the seroprevalence of infection in Mexico, and the socioeconomic and demographic variables that are risk factors for infection. The survey assessed 11,605 sera from a sample population representing persons ages 1-90 years from all socioeconomic and demographic levels and from all regions of Mexico. Antibodies against H. pylori were studied by ELISA using whole cell antigen. Among the findings were that 66% of the population was infected and that age was the strongest risk factor for infection. By age 1 year, 20% were infected and by age 10 years, 50% were infected. Crowding (odds ratio [OR], 1.4), low educational level (OR, 2.42), and low socioeconomic level (OR, 1.43) were risk factors for infection. Prevalence was similar in urban and in rural communities (OR, 0.95). This study is the largest community-based seroepidemiologic study of H. pylori to date. more...

BACKGROUND: Numerous serologic tests are available for the diagnosis of H. pylori infection in children. Common designs of antibody-based detection tests are ELISA and Western Blot (WB). For developing countries with limited laboratory resources and access, ELISA would be the preferred method because of its simplicity, lower cost and speed. Although in adults ELISA has proven to be highly accurate in diagnosing H. pylori infection; in children, it has shown variable accuracy. METHODS/FINDINGS: We conducted a systematic review and meta-analysis to assess the accuracy of antibody-based detection tests for the diagnosis of H. pylori infection in children. Selection criteria included participation of at least 30 children and the use of a gold standard for H. pylori diagnosis. In a comprehensive search we identified 68 studies. Subgroup analyses were carried out by technique, immunoglobulin class, and source of test (commercial and in-house). The results demonstrated: 1) WB tests showed high overall performance, sensitivity 91.3% (95% CI, 88.9-93.3), specificity 89% (95% CI, 85.7-91.9), LR+ 8.2 (95% CI, 5.1-13.3), LR- 0.06 (95% CI, 0.02-0.16), DOR 158.8 (95% CI, 57.8-435.8); 2) ELISA-IgG assays showed low sensitivity 79.2% (95% CI, 77.3-81.0) and high specificity (92.4%, 95% CI, 91.6-93.3); 3) ELISA commercial tests varied widely in performance (test for heterogeneity p more...

Background Neonatal sepsis is a worldwide public health issue in which, depending on the studied population, marked variations concerning its risk and prognostic factors have been reported. The aim of this study was to assess risk and prognostic factors for neonatal sepsis prevailing at a medical unit in southeastern Mexico. Thus, we used a historic cohort design to assess the association between a series of neonates and their mothers, in addition to hospital evolution features and the risk and prognosis of neonatal sepsis (defined by Pediatric Sepsis Consensus [PSC] criteria) in 11,790 newborns consecutively admitted to a Neonatology Service in Mérida, Mexico, between 2004 and 2007. Results Sepsis was found in 514 of 11,790 (4.3 %) newborns; 387 of these cases were categorized as early-onset (72 h) (24.7 %). After logistic regression, risk factors for sepsis included the following: low birth weight; prematurity; abnormal amniotic fluid; premature membrane rupture (PMR) at >24 h; respiratory complications, and the requirement of assisted ventilation, O2 Inspiration fraction (IF) >60 %, or a surgical procedure. Some of these factors were differentially associated with early- or late-onset neonatal sepsis. The overall mortality rate of sepsis was 9.5 %. A marked difference in the mortality rate was found between early- and late-onset sepsis (p >0.0001). After Cox analysis, factors associated with mortality in newborns with sepsis comprised the following: prematurity; low birth weight; low Apgar score; perinatal asphyxia, and the requirement of any invasive medical or surgical procedure. Conclusions The incidence of neonatal sepsis in southeastern Mexico was 4.3 %. A different risk and prognostic profile between early- and late-onset neonatal sepsis was found. more...