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1.
BMC Cancer ; 22(1): 646, 2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35692051

RESUMEN

BACKGROUND: Gastric Cancer (GC) is the fourth most deadly cancer worldwide. Enhanced understanding of its key epidemiological and molecular drivers is urgently needed to lower the incidence and improve outcomes. Furthermore, tumor biology in European (EU) and Latin American (LATAM) countries is understudied. The LEGACy study is a Horizon 2020 funded multi-institutional research approach to 1) detail the epidemiological features including risk factors of GC in current time and 2) develop cost-effective methods to identify and integrate biological biomarkers needed to guide diagnostic and therapeutic approaches with the aim of filling the knowledge gap on GC in these areas. METHODS: This observational study has three parts that are conducted in parallel during 2019-2023 across recruiting centers from four EU and four LATAM countries: Part 1) A case-control study (800 cases and 800 controls) using questionnaires on candidate risk factors for GC, which will be correlated with clinical, demographic and epidemiological parameters. Part 2) A case-control tissue sampling study (400 cases and 400 controls) using proteome, genome, microbiome and immune analyses to characterize advanced (stage III and IV) GC. Patients in this part of the study will be followed over time to observe clinical outcomes. The first half of samples will be used as training cohort to identify the most relevant risk factors and biomarkers, which will be selected to propose cost-effective diagnostic and predictive methods that will be validated with the second half of samples. Part 3) An educational study, as part of our prevention strategy (subjects recruited from the general public) to test and disseminate knowledge on GC risk factors and symptoms by a questionnaire and informative video. Patients could be recruited for more than one of the three LEGACy studies. DISCUSSION: The LEGACy study aims to generate novel, in-depth knowledge on the tumor biological characteristics through integrating epidemiological, multi-omics and clinical data from GC patients at an EU-LATAM partnership. During the study, cost-effective panels with potential use in clinical decision making will be developed and validated. TRIAL REGISTRATION: ClinicalTrials.gov Identifiers: Part 1: NCT03957031 . Part 2: NCT04015466 . Part 3: NCT04019808 .


Asunto(s)
Neoplasias Gástricas , Estudios de Casos y Controles , Toma de Decisiones Clínicas , Humanos , América Latina/epidemiología , Fenotipo , Factores de Riesgo , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/genética
2.
BMC Genomics ; 22(1): 464, 2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34157973

RESUMEN

BACKGROUND: Cylindrospermopsin is a highly persistent cyanobacterial secondary metabolite toxic to humans and other living organisms. Strain OF001 and A210 are manganese-oxidizing bacteria (MOB) able to transform cylindrospermopsin during the oxidation of Mn2+. So far, the enzymes involved in manganese oxidation in strain OF001 and A210 are unknown. Therefore, we analyze the genomes of two cylindrospermopsin-transforming MOB, Pseudomonas sp. OF001 and Rubrivivax sp. A210, to identify enzymes that could catalyze the oxidation of Mn2+. We also investigated specific metabolic features related to pollutant degradation and explored the metabolic potential of these two MOB with respect to the role they may play in biotechnological applications and/or in the environment. RESULTS: Strain OF001 encodes two multicopper oxidases and one haem peroxidase potentially involved in Mn2+ oxidation, with a high similarity to manganese-oxidizing enzymes described for Pseudomonas putida GB-1 (80, 83 and 42% respectively). Strain A210 encodes one multicopper oxidase potentially involved in Mn2+ oxidation, with a high similarity (59%) to the manganese-oxidizing multicopper oxidase in Leptothrix discophora SS-1. Strain OF001 and A210 have genes that might confer them the ability to remove aromatic compounds via the catechol meta- and ortho-cleavage pathway, respectively. Based on the genomic content, both strains may grow over a wide range of O2 concentrations, including microaerophilic conditions, fix nitrogen, and reduce nitrate and sulfate in an assimilatory fashion. Moreover, the strain A210 encodes genes which may convey the ability to reduce nitrate in a dissimilatory manner, and fix carbon via the Calvin cycle. Both MOB encode CRISPR-Cas systems, several predicted genomic islands, and phage proteins, which likely contribute to their genome plasticity. CONCLUSIONS: The genomes of Pseudomonas sp. OF001 and Rubrivivax sp. A210 encode sequences with high similarity to already described MCOs which may catalyze manganese oxidation required for cylindrospermopsin transformation. Furthermore, the analysis of the general metabolism of two MOB strains may contribute to a better understanding of the niches of cylindrospermopsin-removing MOB in natural habitats and their implementation in biotechnological applications to treat water.


Asunto(s)
Alcaloides , Burkholderiales/enzimología , Manganeso , Oxidorreductasas , Pseudomonas/enzimología , Burkholderiales/genética , Toxinas de Cianobacterias , Genoma Bacteriano , Leptothrix , Oxidación-Reducción , Oxidorreductasas/metabolismo , Pseudomonas/genética
3.
Ecotoxicol Environ Saf ; 133: 36-46, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27400062

RESUMEN

Nickel (Ni) is an essential metal for some organisms, but also a common toxic pollutant released into the water. Toxicity of Ni has not been completely established for cyanobacteria; for this reason, we evaluated the effect of sub-inhibitory Ni concentrations on a toxigenic strain of Microcystis aeruginosa and on microcystins production. Population growth, photosynthetic pigments concentration, biomarkers, including antioxidant enzymes (catalase [CAT], glutathione peroxidase [GPx], and superoxide dismutase [SOD]), as well as macromolecules (proteins, carbohydrates and lipids) were quantified; SEM and TEM observations were also performed. Population growth was affected starting at 3µgL(-1), and at 24µgL(-1) growth was completely inhibited; the 96-h Ni(2+) IC50 was 3.7µgL(-1). Ni exposure increased pigments concentration, augmented all the macromolecules, and increased activities of CAT and GPx; alterations on the internal cell structure were also observed. The integrated biomarker response revealed that Ni(2+) augmented the antioxidant response and the macromolecules content. Ni stress also increased microcystins production. M. aeruginosa was affected by Ni at very low concentrations, even lower than those established as safe limit to protect aquatic biota. Aside from the toxic effects produced in this cyanobacterium, stimulation to produce toxins could potentiate the environmental risks associated with water pollution and eutrophication.


Asunto(s)
Microcystis/efectos de los fármacos , Níquel/toxicidad , Proteínas Bacterianas/efectos de los fármacos , Biomarcadores/análisis , Carbohidratos/análisis , Catalasa/efectos de los fármacos , Eutrofización/efectos de los fármacos , Glutatión Peroxidasa/efectos de los fármacos , Lípidos/análisis , Microcistinas/efectos de los fármacos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Fotosíntesis/efectos de los fármacos , Superóxido Dismutasa/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad
4.
Psych J ; 13(1): 113-123, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37905913

RESUMEN

Burnout produces negative effects on academic performance, and, in turn, feelings of inefficiency that are detrimental to students' psychosocial well-being. The aim of this research is to determine the effects that self-compassion and compassion toward others have on various burnout dimensions in a sample of medical students. A total of 235 medical students (61.7% women) aged between 16 and 32 years old (M = 19.82; SD = 2.37) belonging to a Colombian university participated. A cluster analysis to segment the population according to burnout was carried out along with nonparametric contrasts to identify differences in the levels of self-compassion and compassion toward others between each profile. A series of regression analyses was designed to find out how each type of compassion was associated with burnout on each profile. The cluster analysis allowed us to identify three profiles. The low-involvement profile (n = 51) is characterized by low depersonalization, intermediate levels of emotional exhaustion and personal accomplishment and exhibits low levels of self-compassion and compassion fatigue compared with the other profiles. The positive-adaptation profile (n = 104) is characterized by low depersonalization levels, intermediate degrees of emotional exhaustion and high levels of personal accomplishment and exhibits the highest levels of self-compassion and compassion fatigue compared with the other profiles. The high-demand profile (n = 104) is characterized by intermediate depersonalization levels, medium-high levels of emotional exhaustion and high levels of personal accomplishment and exhibits intermediate levels of self-compassion and low levels of compassion fatigue. Establishing profiles based on burnout allows students to be segmented and for precise knowledge to be acquired about the effects that both types of compassion have on the dimensions of burnout.


Asunto(s)
Agotamiento Profesional , Desgaste por Empatía , Estudiantes de Medicina , Humanos , Femenino , Adolescente , Adulto Joven , Adulto , Masculino , Desgaste por Empatía/psicología , Empatía , Autocompasión , Agotamiento Profesional/epidemiología , Agotamiento Profesional/psicología , Agotamiento Emocional , Encuestas y Cuestionarios
5.
Biomedica ; 44(1): 35-44, 2024 03 31.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38648348

RESUMEN

INTRODUCTION: Metabolic bone disease of premature infants is a rare complication characterized by a lower mineral content in bone tissue. OBJECTIVE: To establish the incidence of metabolic bone disease in premature infants and to determine associated risk factors. MATERIALS AND METHOD: We conducted a descriptive prospective cohort study for one year in all newborns under 32 gestational weeks, or 1,500 g, at the Hospital Universitario de Santander to determine the incidence of metabolic bone disease. We collected demographic data and prenatal histories of the selected patients, and later, we measured serum alkaline phosphatase and serum phosphorus at the third week of birth, having as reference values for diagnosis less than 5.6 mg/dl for the first one and more than 500 UI/L for the second one. We applied statistical tools for data analysis, such as average proportions, dispersion, distribution and association measures, and binomial regression. RESULTS: From a total of 58 patients, 7 had a diagnosis of metabolic bone disease, with an incidence of 12%. The weight was reported as an independent variable for the development of the disease, being significant in children under 1,160 g, as well as prolonged parenteral nutrition for more than 24 days. When performing the multivariate analysis, low weight and short time of parenteral nutrition appeared as risk factors; in the same way, maternal age below 22 years is associated with a higher relative risk, even more than a newborn weight inferior to 1,160 g. CONCLUSION: Establishing an early intervention in patients with metabolic bone disease enhancing risk factors, such as low weight and prolonged parenteral nutrition, is critical to prevent severe complications.


Introducción. La enfermedad metabólica ósea de neonatos prematuros es una complicación poco común que se caracteriza por una disminución del contenido mineral en el hueso. Objetivo. Establecer la incidencia de la enfermedad metabólica ósea en neonatos prematuros y los factores de riesgo asociados. Materiales y métodos. Durante un año, se realizó un estudio prospectivo de cohorte, descriptivo, con todos los neonatos nacidos con menos de 32 semanas de gestación o un peso menor de 1.500 g en el Hospital Universitario de Santander. Se recolectaron datos demográficos y antecedentes prenatales de los pacientes seleccionados. A la tercera semana de nacimiento, se midieron la fosfatasa alcalina y el fósforo sérico, tomando como valores de referencia diagnóstica aquellos inferiores a 5,6 mg/dl para el primero y aquellos mayores de 500 UI/L para la segunda. Para el análisis de la información, se emplearon herramientas estadísticas, como proporciones de promedios, medidas de dispersión, distribución y asociación, y regresión binomial. Resultados. De un total de 58 pacientes, 7 tuvieron diagnóstico de enfermedad metabólica ósea, con una incidencia del 12 %. De las variables estudiadas, el peso se reportó como una variable independiente para el desarrollo de la enfermedad, significativa en aquellos neonatos con peso menor de 1.160 g, al igual que la nutrición parenteral prolongada por más de 24 días. Al hacer el análisis multivariado, La edad materna menor de 22 años representó un riesgo relativo mayor, en comparación con un peso inferior a 1.160 g. Conclusión. Se estableció la importancia de una intervención temprana en pacientes con factores de riesgo para enfermedad metabólica ósea, como bajo peso (menor de 1.160 g) y nutrición parenteral prolongada (mayor de 24 días), con el fin de prevenir complicaciones graves.


Asunto(s)
Enfermedades Óseas Metabólicas , Humanos , Colombia/epidemiología , Recién Nacido , Incidencia , Enfermedades Óseas Metabólicas/epidemiología , Estudios Prospectivos , Femenino , Masculino , Factores de Riesgo , Edad Gestacional , Nutrición Parenteral , Recien Nacido Prematuro , Fosfatasa Alcalina/sangre , Enfermedades del Prematuro/epidemiología , Enfermedades del Prematuro/sangre , Hospitales Universitarios , Fósforo/sangre
6.
Environ Pollut ; 344: 123437, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38272168

RESUMEN

Metolachlor (MET) is a widely used herbicide that can adversely affect phytoplanktonic non-target organisms, such as cyanobacteria. Chytrids are zoosporic fungi ubiquitous in aquatic environments that parasitize cyanobacteria and can keep their proliferation in check. However, the influence of organic pollutants on the interaction between species, including parasitism, and the associated ecological processes remain poorly understood. Using the host-parasite system consisting of the toxigenic cyanobacterium Planktothrix agardhii and its chytrid parasite Rhizophydium megarrhizum, we investigated the effects of environmentally relevant concentrations of MET on host-parasite interactions under i) continuous exposure of chytrids and cyanobacteria, and ii) pre-exposure of chytrids. During a continuous exposure, the infection prevalence and intensity were not affected, but chytrid reproductive structures were smaller at the highest tested MET concentration. In the parasite's absence, MET promoted cyanobacteria growth possibly due to a hormesis effect. In the pre-exposure assay, MET caused multi- and transgenerational detrimental effects on parasite fitness. Chytrids pre-exposed to MET showed reduced infectivity, intensity, and prevalence of the infection, and their sporangia size was reduced. Thus, pre-exposure of the parasite to MET resulted in a delayed decline of the cyanobacterial cultures upon infection. After several parasite generations without MET exposure, the parasite recovered its initial fitness, indicating that detrimental effects are transient. This study demonstrates that widely used herbicides, such as MET, could favor cyanobacterial bloom formation both directly, by promoting cyanobacteria growth, and indirectly, by inhibiting their chytrid parasites, which are known to play a key role as top-down regulators of cyanobacteria. In addition, we evidence the relevance of addressing multi-organism systems, such as host-parasite interactions, in toxicity assays. This approach offers a more comprehensive understanding of the effects of pollutants on aquatic ecosystems.


Asunto(s)
Acetamidas , Quitridiomicetos , Cianobacterias , Contaminantes Ambientales , Parásitos , Animales , Ecosistema
7.
Ann Otol Rhinol Laryngol ; 133(5): 485-489, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38344993

RESUMEN

BACKGROUND: Commonly used endoscopic nasal polyp grading scales have been shown to correlate poorly with symptom scores and quality of life metrics. The recently described Postoperative Polyp Scale (POPS) is a grading system that more accurately characterizes polyp recurrence in postoperative sinus cavities by describing incremental recurrence in relation to the surgically opened sinus cavities. OBJECTIVE: The objective of this study was to determine if the POPS correlated with sinonasal symptoms. METHODS: CRSwNP patients were prospectively administered SNOT-22 questionnaires and graded according to the POPS starting at their 1-month postoperative appointments. Total POPS scores (sum of each side) and Max POPS score (larger value of left and right) were correlated with SNOT-22 total scores and subdomains using Kendall correlation testing. RESULTS: A total of 127 patients were enrolled in the study. Both Total POPS or Max POPS were significantly correlated to the SNOT-22 total score (P < .001, P < .001), Rhinologic (P < .001, P < .001), Extra-Nasal Rhinologic (P < .001, P < .001), Ear/Facial (P < .001, P < .001), and Psychologic (P = .028, P = .017) subdomains. Kendall's tau indicated strong correlation (≥0.3) with Rhinologic subdomain, moderate correlation (.21-.29) with Extra-Nasal Rhinologic and Ear/Facial subdomains, and weak correlation (.1-.19) with Psychologic subdomain. CONCLUSION: Previous endoscopic nasal polyp grading scales poorly correlate with symptoms and patient reported outcome measures. The new POPS moderately correlates with the total SNOT-22 score and strongly correlates with the Rhinologic subdomain, indicating that it may have good potential as a tool to evaluate postoperative CRSwNP patients.


Asunto(s)
Pólipos Nasales , Rinitis , Sinusitis , Humanos , Sinusitis/cirugía , Pólipos Nasales/diagnóstico , Pólipos Nasales/cirugía , Calidad de Vida , Rinitis/cirugía , Enfermedad Crónica , Endoscopía
8.
Front Oncol ; 14: 1304263, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38444682

RESUMEN

Introduction: Acute leukemias (AL) are the main types of cancer in children worldwide. In Mexico, they represent one of the main causes of death in children under 20 years of age. Most of the studies on the incidence of AL in Mexico have been developed in the urban context of Greater Mexico City and no previous studies have been conducted in the central-south of the country through a population-based study. The aim of the present work was to identify the general and specific incidence rates of pediatric AL in three states of the south-central region of Mexico considered as some of the marginalized populations of Mexico (Puebla, Tlaxcala, and Oaxaca). Methods: A population-based study was conducted. Children aged less than 20 years, resident in these states, and newly diagnosed with AL in public/private hospitals during the period 2021-2022 were identified. Crude incidence rates (cIR), standardized incidence rates (ASIRw), and incidence rates by state subregions (ASIRsr) were calculated. Rates were calculated using the direct and indirect method and reported per million children under 20 years of age. In addition, specific rates were calculated by age group, sex, leukemia subtype, and immunophenotype. Results: A total of 388 cases with AL were registered. In the three states, the ASIRw for AL was 51.5 cases per million (0-14 years); in Puebla, it was 53.2, Tlaxcala 54.7, and Oaxaca de 47.7. In the age group between 0-19 years, the ASIRw were 44.3, 46.4, 48.2, and 49.6, in Puebla, Tlaxcala, and Oaxaca, respectively. B-cell acute lymphoblastic leukemia was the most common subtype across the three states. Conclusion: The incidence of childhood AL in the central-south region of Mexico is within the range of rates reported in other populations of Latin American origin. Two incidence peaks were identified for lymphoblastic and myeloid leukemias. In addition, differences in the incidence of the disease were observed among state subregions which could be attributed to social factors linked to the ethnic origin of the inhabitants. Nonetheless, this hypothesis requires further investigation.

9.
Soc Work Health Care ; 52(1): 1-19, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23301932

RESUMEN

Latinos underutilize mental health care services. Of those who do, about 70% do not return after the initial visit. This study's purposes were: (1) to identify factors that led non-U.S.-born Latinos to utilize services from a nonprofit clinic in Texas and (2) to assess whether acculturation played a role in accessing mental health care. Data were collected over a 10-week period using an interview schedule and the Bidimensional Acculturation Scale for Latinos. Results indicate acculturation does not play a significant role in access, but patient knowledge of mental health care issues does. Specifically, the main barriers to access were: (1) lack of knowledge that there was a mental health issue; and (2) lack of knowledge of where to go for mental health services.


Asunto(s)
Accesibilidad a los Servicios de Salud , Hispánicos o Latinos/psicología , Servicios de Salud Mental/estadística & datos numéricos , Aculturación , Adulto , América Central/etnología , Femenino , Conocimientos, Actitudes y Práctica en Salud/etnología , Humanos , Modelos Logísticos , Masculino , México/etnología , Persona de Mediana Edad , Aceptación de la Atención de Salud/etnología , Aceptación de la Atención de Salud/psicología , Encuestas y Cuestionarios , Texas
10.
Rev Med Inst Mex Seguro Soc ; 51(1): 86-91, 2013.
Artículo en Español | MEDLINE | ID: mdl-23556170

RESUMEN

OBJECTIVE: To evaluate the effect of non-surgical periodontal treatment on the metabolic control, measured by HbA1c in uncontrolled type 2 diabetes mellitus patients with periodontal disease treated with the ADA-EASD algorithm. METHODS: The study group consisted of 38 patients diagnosed with type 2 diabetes mellitus and periodontal disease, attending a benefit clinic. HbA1c measures were obtained before and after 3 months of the non-surgical periodontal treatment. T student test for dependent samples was applied with a p value less than 0.05 for statistical significance. RESULTS: From the total sample, 79% was female, and mean age was of 51 +/- 9.8 years old. Mean HbA1c at baseline was of 8.6 and 8% at exit. The mean reduction was statistically significant (p = 0.026). After non-surgical periodontal treatment, the prevalence of periodontal disease was of 8%. The mean of personal plaque control before and after the treatment decreased from 82.6% to 35.5% (p < 0.000). CONCLUSIONS: Consistent with similar previous studies, in this study we demonstrate progress in glycemic control, remission of periodontal disease and improved personal plaque control.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Enfermedades Periodontales/complicaciones , Enfermedades Periodontales/terapia , Diabetes Mellitus Tipo 2/sangre , Femenino , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad
11.
Psychol Rep ; : 332941221132995, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36219581

RESUMEN

OBJECTIVE: To examine the relationship between self-compassion, compassion for others and Burnout in medical students and physicians. METHODS: A cross-sectional study was conducted. Medicine students and general physicians from two Colombian cities participated (n = 359). The Compassion Scales and the Maslach Inventory were administered. An Exploratory Structural Equation approach was used for validating new measures and testing for relationships between latent variables. RESULTS: Most participants were students (85.9%), mean age was 22 years (SD = 7), 55.2% were female, 62,6% dedicated more than 48 weekly hours to study or practice, while physicians had worked a mean of 10.34 years (SD = 8.67). Self-compassion and Compassion for others action subscales were validated, but engagement subscales of were not. Participant´s compassion actions for others and self-compassion actions are negatively related to depersonalization and emotional exhaustion, respectively. Additionally, compassion dimensions were positively associated with professional accomplishment. CONCLUSION: Our findings indicate that compassion and self-compassion actions inversely relate to different components of Burnout and could constitute protective factors against the stress of healthcare. Compassion and self-compassion training programs for medical students and physicians might be an alternative to avoid Burnout, diminishing physicians' depersonalization and emotional exhaustion while enhancing their professional accomplishment.

12.
Chemosphere ; 238: 124625, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31466008

RESUMEN

The cyanotoxin cylindrospermopsin was discovered during a drinking water-related outbreak of human poisoning in 1979. Knowledge about the degradation of cylindrospermopsin in waterbodies is limited. So far, only few cylindrospermopsin-removing bacteria have been described. Manganese-oxidizing bacteria remove a variety of organic compounds. However, this has not been assessed for cyanotoxins yet. We investigated cylindrospermopsin removal by manganese-oxidizing bacteria, isolated from natural and technical systems. Cylindrospermopsin removal was evaluated under different conditions. We analysed the correlation between the amount of oxidized manganese and the cylindrospermopsin removal, as well as the removal of cylindrospermopsin by sterile biogenic oxides. Removal rates in the range of 0.4-37.0 µg L-1 day-1 were observed. When MnCO3 was in the media Pseudomonas sp. OF001 removed ∼100% of cylindrospermopsin in 3 days, Comamonadaceae bacterium A210 removed ∼100% within 14 days, and Ideonella sp. A288 and A226 removed 65% and 80% within 28 days, respectively. In the absence of Mn2+, strain A288 did not remove cylindrospermopsin, while the other strains removed 5-16%. The amount of manganese oxidized by the strains during the experiment did not correlate with the amount of cylindrospermopsin removed. However, the mere oxidation of Mn2+ was indispensable for cylindrospermopsin removal. Cylindrospermopsin removal ranging from 0 to 24% by sterile biogenic oxides was observed. Considering the efficient removal of cylindrospermopsin by the tested strains, manganese-oxidizing bacteria might play an important role in cylindrospermopsin removal in the environment. Besides, manganese-oxidizing bacteria could be promising candidates for biotechnological applications for cylindrospermopsin removal in water treatment plants.


Asunto(s)
Toxinas Bacterianas/análisis , Burkholderiales/metabolismo , Comamonadaceae/metabolismo , Manganeso/metabolismo , Pseudomonas/metabolismo , Uracilo/análogos & derivados , Purificación del Agua/métodos , Alcaloides , Toxinas de Cianobacterias , Agua Potable/metabolismo , Compuestos de Manganeso/metabolismo , Oxidación-Reducción , Óxidos/metabolismo , Uracilo/análisis
13.
Sci Total Environ ; 729: 138924, 2020 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-32361450

RESUMEN

Cylindrospermopsin (CYN) is a toxic alkaloid highly persistent in aquatic environments. Biological removal of CYN was described previously. However, no transformation products formed by biological processes could be identified so far. Here, we describe that various manganese-oxidizing bacteria (MOB) transform CYN completely at an initial mean concentration of 7 mg L-1 (17 µM) within 3 to 34 days. Regardless of the strain, and transformation rate, transformation of CYN by MOB led to the same seven transformation products identified by mass spectrometry, which suggests that the removal of CYN by MOB follows a similar mechanism. Oxidation was the main transformation process, and the uracil moiety was the most susceptible part of the CYN molecule. In vitro cytotoxicity tests with the transformation products of CYN formed by one of the tested strains against the two human liver cell lines HepG2 and HepaRG, revealed that the transformation products were substantially less toxic than pure CYN for both cell lines. The results suggest that incubation with MOB might be an option for water treatment to remove CYN and may allow more detailed studies on the fate of CYN in the environment.


Asunto(s)
Bacterias , Alcaloides , Toxinas Bacterianas , Toxinas de Cianobacterias , Humanos , Hígado , Manganeso , Oxidación-Reducción , Uracilo/análogos & derivados
14.
Ann Diagn Pathol ; 13(3): 151-7, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19433292

RESUMEN

Neoadjuvant chemotherapy is the standard of care for patients with locally advanced breast cancer and is used increasingly for large operable breast cancer. The aim of this study was to assess the rate of pathologic complete response (pCR) in our patient population with locally advanced breast cancer and identify predictive factors for pCR after neoadjuvant chemotherapy. We studied a cohort of 205 patients and compared histologic features and biomarkers in the pretreatment biopsy with the corresponding pathologic response in the subsequent resection specimen. A pCR was defined as the absence of any microscopic evidence of tumor in the mastectomy specimen and axillary lymph node dissection. The tumor size was reduced in 60% of patients; 16 patients had a pCR. Histologic grade, histologic type, and hormone status did correlate with a pathologic response. None of the 29 invasive pure micropapillary carcinomas had a pCR. Pathologic complete response among Mexican patients with locally advanced breast cancer is low (8%), and the presence of invasive pure micropapillary carcinoma could be an independent predictor for pCR.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Terapia Neoadyuvante , Adulto , Anciano , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática/patología , Mastectomía , Persona de Mediana Edad , Estadificación de Neoplasias , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Estudios Retrospectivos , Resultado del Tratamiento
15.
Hematol Rep ; 11(3): 7964, 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-31579151

RESUMEN

The aim of this study is to explore the expression of osteopontin (OPN) and its relationship with prognostic factors and survival in diffuse large B cell lymphoma (DLBCL). A tissue microarray was performed for immunohistochemical evaluation. Contingency tables were analyzed for trends; chi-square test was used to determine differences between groups. Univariate and multivariate Cox proportional hazards-regression analyses were performed to evaluate the impact of prognostic factors on survival. Expression of OPN was observed in 28%. It was different in non-germinal center DLBCL (P=0.04). The mean overall survival (OS) was lower in patients with positive OPN expression (19.762; CI 95% 14.269-25.255) it was not significant (P=0.123). It is not possible to establish a clear relationship between the expression by immunohistochemistry of osteopontin and a poor prognosis but it would be important to complement the analysis with other techniques as PCR or NGS that allow us to assess the influence of the isoforms and post-translational modifications of OPN on the biological behavior of DLBCL. Our findings indicate that OPN expression could be associated with a more aggressive variant of lymphoma: non-germinal center DLBCL.

16.
Health Promot Perspect ; 8(1): 46-53, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29423362

RESUMEN

Background: Latino day laborers (LDLs) experience chronic stressors, that adversely affects their subjective well-being (SWB). The purpose of the study was to determine whether LDLs' sociodemographic characteristics, religiosity, social networks, and cigarette use were significantly associated with SWB. Methods: AApproximately 150 LDLs from 4 informal day laborer sites in Dallas and Arlington, Texas, participated in the cross-sectional survey. Informed consent was obtained from all participants and data on SWB were collected face-to-face from April 2013 through July 2013. Results: Most respondents were of Mexican ancestry, (n = 112; 75%), were foreign-born (n = 140; 93%), and undocumented (n = 108; 72%). LDLs reported a mean satisfaction with life score of 19.07 (SD=8.52). Thirty percent of LDLs reported not smoking any cigarettes in the past 30 days. However, 20% reported smoking 20-39 cigarettes, while another 20% reported smoking 40 or more cigarettes in the past 30 days. Hierarchical multiple regression results indicated that marital status (ß = 0.13, P ≤ 0.05), connectedness to friends (ß = 0.21, P ≤ 0.001), the influence of religion on life (ß = 0.57, P ≤ 0.01), frequency of attendance to religious institution (ß = 0.11, P ≤ 0.005), and cigarette use (ß = -0.15, P ≤ 0.05) were significantly associated with the SWB appraisals of LDLs. Conclusion: These findings show that LDLs are resilient and rely on noneconomic factors to enhance their perceived quality of life. The results underscore the need to identify pathways to improve SWB among LDLs. Doing so may address the broader mental health and occupational health disparities gaps that affect LDLs.

17.
Sci Total Environ ; 619-620: 1566-1578, 2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-29070448

RESUMEN

The extensive use of 2,4-dichlorophenoxiacetic acid (2,4-D) in agriculture is an important source of pollution to water and soil. Toxicity of commonly used herbicides to non-target, planktonic photosynthetic organisms has not been described completely yet. Therefore, we determined the effect of subinhibitory 2,4-D concentrations on the Chlorophycean alga Ankistrodesmus falcatus and on a toxigenic strain of the cyanobacterium Microcystis aeruginosa. Population growth, photosynthetic pigments, macromolecular biomarkers (carbohydrates, lipids, and protein), and antioxidant enzymes (catalase [CAT], glutathione peroxidase [GPx], and superoxide dismutase [SOD]) were quantified, and the integrated biomarker response (IBR) was calculated. Scanning electron microscope (SEM) and transmission electron microscope (TEM) observations were also performed. The 96-h median inhibitory concentration (IC50) for 2,4-D was 1353.80 and 71.20mgL-1 for the alga and the cyanobacterium, respectively. Under 2,4-D stress, both organisms increased pigments and macromolecules concentration, modified the activity of all the evaluated enzymes, and exhibited ultrastructural alterations. M. aeruginosa also increased microcystins production, and A. falcatus showed external morphological alterations. The green alga was tolerant to high concentrations of the herbicide, whereas the cyanobacterium exhibited sensitivity comparable to other phytoplankters. Both organisms were tolerant to comparatively high concentrations of the herbicide; however, negative effects on the assessed biomarkers and cell morphology were significant. Moreover, stimulation of the production of cyanotoxins under chemical stress could increase the risk for the biota in aquatic environments, related to herbicides pollution in eutrophic freshwater ecosystems.


Asunto(s)
Ácido 2,4-Diclorofenoxiacético/toxicidad , Herbicidas/toxicidad , Microalgas/efectos de los fármacos , Microcystis/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Microcistinas/biosíntesis
18.
Rev Chilena Infectol ; 35(6): 658-668, 2018.
Artículo en Español | MEDLINE | ID: mdl-31095186

RESUMEN

BACKGROUND: Dengue and chikungunya viruses are transmitted by the female Aedes aegypti and Aedes albopictus, which are widely distributed in tropical and subtropical areas, facilitating coinfection. AIM: To determine the magnitude, geographical distribution and clinical picture of dengue and chikungunya coinfection. MATERIAL AND METHODS: Narrative review. A search in the PubMed and Lilacs databases was made, using the MeSH terms "Chikungunya", "CHIKV", "DENV", "Dengue" and "coinfection. The articles of the last 20 years were included. RESULTS: A total of 45 articles were included. The largest coinfection report was in Asia followed by Africa. In the Americas, the information is limited because of the recent circulation of chikungunya. The magnitude of coinfection varies between 0% and 31.9%. No differences were found in the distribution of coinfection by sex and age. The clinical picture of monoinfection and coinfection was similar. Some case reports show severe cases with central nervous system involvement, hemorrhagic manifestations and Still's disease. CONCLUSION: The clinical manifestations of coinfection by dengue and chikungunya viruses are similar to those due to monoinfection, which difficult the diagnosis and measurement of its magnitude.


Asunto(s)
Fiebre Chikungunya/virología , Coinfección/virología , Dengue/virología , Animales , Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/mortalidad , Fiebre Chikungunya/transmisión , Virus Chikungunya/genética , Coinfección/diagnóstico , Coinfección/mortalidad , Coinfección/transmisión , Dengue/diagnóstico , Dengue/mortalidad , Dengue/transmisión , Virus del Dengue/genética , Genotipo , Geografía , Humanos , Mosquitos Vectores , Índice de Severidad de la Enfermedad
19.
Environ Sci Pollut Res Int ; 24(21): 17534-17546, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28597380

RESUMEN

Chapalichthys pardalis is a viviparous fish, microendemic to the Tocumbo Region in the state of Michoacán, Mexico. Despite the peculiar type of reproduction of goodeid fish and their mother-embryo interaction, the effects on embryos induced by maternal exposure to aquatic xenobiotics are still unknown. The objective of the present work was to determine the maternal-embryonic metabolic and antioxidant response of C. pardalis exposed to 3,4-dichloroaniline (3,4-DCA), a compound considered highly noxious to the environment because of its high toxicity and persistence, which has been used as reference toxicant in toxicological bioassays. We determined the median lethal concentration (LC50, 96 h) and then exposed pregnant females to 3.3, 2.5, and 0.5 mg L-1 of 3,4-DCA (equivalent to LC1, LC0.01, and LC50/10, respectively) during 21 days. We assessed the activity of antioxidant enzymes like superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), macromolecules content (proteins, lipids, carbohydrates), glucose, and lactate concentration, as well as the oxidative damage, by measuring thiobarbituric acid reactive substances, and protein oxidation. To interpret results, we used the integrated biomarker response (IBRv2). The average LC50 was of 5.18 mg L-1 (4.8-5.5 mg L-1; p = 0.05). All females exposed to concentrations of 3.3 and 2.5 mg L-1 lost 100% of the embryos during the bioassay, whereas those exposed to 0.5 mg L-1 showed alterations in the antioxidant activity and oxidative damage, being the embryos and the maternal liver the most affected, with IBRv2 values of 10.09 and 9.21, respectively. Damage to macromolecules was greater in embryos and the maternal liver, with IBRv2 of 16.14 and 8.40, respectively. We conclude that exposure to xenobiotics, like 3,4-DCA, in species with a marked maternal-embryonic interaction represents a potential risk for the development and survival of the descendants, thereby, potentially affecting the future of the population.


Asunto(s)
Compuestos de Anilina/uso terapéutico , Antioxidantes , Peces/fisiología , Contaminantes Químicos del Agua/toxicidad , Animales , Catalasa , Femenino , México , Estrés Oxidativo , Embarazo , Preñez , Superóxido Dismutasa
20.
Sci Total Environ ; 583: 308-318, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28117161

RESUMEN

Silver nanoparticles (AgNPs) are the most commercialized nanomaterial worldwide, mainly due to their microbicidal activity. Although, AgNPs have been shown to be toxic to aquatic species, their effect on endemic fish, like Goodeidae, has not been demonstrated. Endemic species are under strong pressures by anthropogenic contamination and destruction of their habitat; therefore, we studied adult Chapalichthys pardalis, an endemic fish of Mexico. We evaluated the toxic effect of AgNPs through oxidative stress, macromolecular and metabolic biomarkers. We determined the LC50 (96h) and performed subchronic tests (21days) using sublethal AgNPs concentrations (equivalent to CL1 and CL10). At the end of the bioassay, we quantified 10 stress biomarkers in the liver, gills, and muscle, including the antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT], and glutathione [GPx]), thiobarbituric acid reactive species (TBARS), protein oxidation (CO), macromolecules (proteins, lipids, and carbohydrates), and metabolites (glucose and lactate). In addition, we determined the integrated biomarkers response (IBR). LC50 was of 10.32mgL-1. Results of subchronic exposure (21days) revealed that AgNPs produce oxidative stress in C. pardalis adults, as evidenced by a diminution in antioxidant enzymes activity and an increase in TBARS and oxidized proteins. AgNPs also diminished levels of macromolecules and generated a high-energy consumption, reflected in the reduction of glucose levels, although lactate levels were not altered. The IBR analysis evidenced that the largest effect was produced in organisms exposed to LC10, being the liver and gills the organs with the greatest damage. Results demonstrated that exposure to AgNPs induces acute and chronic toxic effects on C. pardalis and forewarns about the impact that these nanomaterials can exert on these ecologically relevant aquatic organisms.


Asunto(s)
Ciprinodontiformes/fisiología , Nanopartículas del Metal/toxicidad , Estrés Oxidativo/fisiología , Plata/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Catalasa/metabolismo , Superóxido Dismutasa/metabolismo , Sustancias Reactivas al Ácido Tiobarbitúrico/metabolismo , Pruebas de Toxicidad
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