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Resumen La combinación de la actividad metabólica de cepas bacterianas potencializa la actividad antimicrobiana contra microorganismos patógenos, en comparación con la actividad que pueden presentar las cepas microbianas en forma individual. La formulación mixta de bacterias acido lácticas ha sido estudiada para la producción de preparados probióticos con actividad antimicrobiana contra patógenos. Listeria monocytogenes es considerado un microorganismo patógeno para el hombre y animales, causando principalmente, la enfermedad conocida como listeriosis. Se evaluó la actividad antimicrobiana de una formulación mixta de Lactobacillus brevis y Weisella cibaria frente a Listeria monocytogenes. L. brevis y W. cibaria se reprodujeron por fermentaciones en discontinuo durante 48 horas. Se midió la cinética de la actividad antimicrobiana contra L. monocytogenes en los siguientes tiempos de fermentación, 0, 1, 2, 6, 12, 24 y 48 horas. En cada tiempo, la actividad antimicrobiana de la mezcla de cepas se comparó con la actividad antimicrobiana de las cepas en forma individual. La actividad antimicrobiana se midió mediante el diámetro de Feret, utilizando un software de evaluación de imágenes. Se encontró que la actividad antimicrobiana de la mezcla de cepas contra L. monocytogenes fue estable desde la segunda hora de fermentación hasta las 48 horas. A partir de 18 horas de fermentación la mezcla de cepas presentó actividad antimicrobiana superior, comparada con las cepas individuales. Los resultados indican que la formulación mixta de L. brevis y W. cibaria podría ser una opción biotecnológica para el desarrollo de antimicrobianos naturales para el control y prevención de L. monocytogenes.
Abstract The combination of the metabolic activity of bacterial strains potentiates the antimicrobial activity against pathogenic microorganisms, in comparison with the activity that the microbial strains can present individually. The mixed formulation of lactic acid bacteria has been studied to the production of probiotic preparations with antimicrobial activity against pathogens. Listeria monocytogenes is considered a pathogenic microorganism for man and animals, causing the disease known as listeriosis. The antimicrobial activity of a mixed formulation of Lactobacillus brevis and Weisella cibaria was evaluated against Listeria monocytogenes. L. brevis and W. cibaria were reproduced by discontinuous fermentations for 48 hours. The kinetics of antimicrobial activity against L. monocytogenes were measured at the next fermentation times, 0, 1, 2, 6, 12, 24 and 48 hours. At each time, the antimicrobial activity of the mixed formulation was compared with the antimicrobial activity of the strains individually. The antimicrobial activity was measured by Feret's diameter, using image evaluation software. It was found that the antimicrobial activity of the mixed formulation against L. monocytogenes was stable from the second hour of fermentation to 48 hours of fermentation. After 18 hours of fermentation the mixed formulation presented superior antimicrobial activity, compared to the individual strains. The results indicate that the mixed formulation of L. brevis and W. cibaria could be a biotechnological option for the development of natural antimicrobials for the control and prevention of L. monocytogenes.
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Hexagonal (W,V)O3-x oxides of high thermal stability have been synthesized hydrothermally through the intermediate products Nax(W,V)O3·zH2O and (NH4)0.33-x(W,V)O3-y. The obtained crystals show nanostructured surface via the formation of a dense population of polyhedral nanocavities self-distributed along particular crystallographic directions. Nanocavities present a regular size that ranges from 5 to 10 nm in both length and width. The synthesis process involves a significant topotactic relationship between the as-synthesized product and the desired final product and this relationship is suggested as the origin of the observed surface nanostructure. The comparison of our results with observations in different solids has allowed us to suggest that the formation of nanocavities is an extensive spontaneous process when materials are obtained by the chemical reactions of solids leading to products with defined crystallographic orientation with respect to the original compound. The characterization provides evidence regarding the potential relevance of nanocavities in the functional properties of the resulting solids.
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OBJECTIVE: To verify whether synthetic cannabinoids (CP55,940 and WIN55,212-2) are able to exert an anti-inflammatory effect on rheumatoid fibroblast-like synoviocytes (FLS) by down-regulating cytokine production, and determine whether this effect could be mediated by CB1/CB2 cannabinoid receptors. METHODS: Interleukin-6 (IL-6) and interleukin-8 (IL-8) were assayed in the supernatant from cultured FLS by ELISA method before and after 3 hours of incubation with CP55,940 (10 microM) and WIN55,212-2 (10 microM). Co-stimulation of cells with the cannabinoid receptor antagonists was performed to evaluate receptor involvement in cytokine modulation. All the experiments were conducted in basal conditions and after 1 hour pre-incubation with 0.1 ng/ml IL-1beta. FLS expression of CB1 and CB2 receptor was studied by Western Blot analyses. RESULTS: Both CP55,940 and WIN55,212-2 induced a potent and significant reduction in IL-6 and IL-8 secretion from IL-1beta. stimulated FLS. Although FLS express CB1 and CB2 receptor, cannabinoid receptor antagonists did not significantly modify the inhibition of cytokines secretion induced by CP55,940 and WIN55,212-2. CONCLUSIONS: In vitro, CP55,940 and WIN55,212-2 exert a potent anti-inflammatory effect on rheumatoid FLS via a non-CB1/CB2 receptor mediated mechanism.
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Antiinflamatorios/farmacología , Artritis Reumatoide/inmunología , Benzoxazinas/farmacología , Ciclohexanoles/farmacología , Fibroblastos/efectos de los fármacos , Morfolinas/farmacología , Naftalenos/farmacología , Membrana Sinovial/efectos de los fármacos , Anciano , Artritis Reumatoide/tratamiento farmacológico , Artritis Reumatoide/metabolismo , Estudios de Cohortes , Femenino , Fibroblastos/inmunología , Fibroblastos/metabolismo , Humanos , Técnicas In Vitro , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/metabolismo , Receptor Cannabinoide CB1/metabolismo , Receptor Cannabinoide CB2/metabolismo , Membrana Sinovial/inmunología , Membrana Sinovial/metabolismoRESUMEN
OBJECTIVE: To compare levels of a range of endothelial progenitor cells (EPCs) and endothelial colony-forming units (CFUs) in control participants and RA patients, in addition to verifying whether levels of EPCs or CFUs are associated with clinical characteristics in RA patients. METHODS: Peripheral blood mononuclear cells (PBMCs) from 36 RA patients and 30 control participants were analysed by flow cytometry for EPCs defined by the expression of CD34/CD133, CD34/CD117, CD34/CD31, CD34/KDR and CD34/CD133/KDR. Endothelial cell colonies derived from culture of PBMCs were also assessed by CFU assay. RESULTS: No differences in levels of EPCs were observed in RA patients compared with controls. However, levels of EPCs were negatively associated with prognostic markers of poor disease status, but not cardiovascular (CV)-related risk factors. Furthermore, the majority of EPCs examined were negatively correlated with levels of RF. In contrast, CFU number was significantly reduced in RA patients compared with controls and was negatively associated with CV risk factors only. CONCLUSION: These findings indicate that more informative than comparing changes in absolute levels of EPCs, the examination of their relationship with clinical characteristics of RA patients can reveal significant associations, which may provide important clinical insights.
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Artritis Reumatoide/sangre , Células Madre Hematopoyéticas/patología , Anciano , Sedimentación Sanguínea , Enfermedades Cardiovasculares/etiología , Células Cultivadas , Ensayo de Unidades Formadoras de Colonias , Células Endoteliales/patología , Endotelio Vascular/patología , Femenino , Humanos , Recuento de Linfocitos , Masculino , Pronóstico , Factor Reumatoide/sangre , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
OBJECTIVE: To present a case of granular cell tumor with an uncommon localization. METHODS: A 38-year-old patient presented with a painless nodule 10 mm in diameter on the scrotum that he had noted two years earlier. RESULTS: The tumor was surgically excised. Pathological analysis demonstrated a granular cell tumor that was strongly positive for protein S-100 and negative for cytokeratin AE1-AE3 and CEA. CONCLUSIONS: Granular cell tumors are very frequent in the head and neck, but rare in the genitourinary region and are asymptomatic. Histological diagnosis is simple but should be confirmed by protein S-100 staining, which is positive in all cases. Treatment is by simple excision of the lesion. Tumor recurrence and metastasis have been reported, therefore follow-up is necessary.
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Neoplasias de los Genitales Masculinos/patología , Tumor de Células Granulares/patología , Escroto , Adulto , Humanos , MasculinoRESUMEN
BACKGROUND: Pemphigoid gestationis (PG), also called herpes gestationis, is a rare autoimmune disease of pregnancy or puerperium (estimated 1 out of 50,000 pregnancies among Caucasians). A previous series has demonstrated an association of PG with human leukocyte antigen (HLA)-DR3 or HLA-DR4 haplotypes. While these haplotypes are most commonly found in individuals of European ancestry, they have also been found in African-American patients affected with PG. PG has rarely been reported in other ethnic groups, and the HLA association in non-Europeans has not been examined. METHODS: We have characterized eight patients of Mexican ancestry who have PG by clinical, histologic, and immunofluorescence criteria. Class I and class II major histocompatibility complex (MHC) antigens were studied by standard microlymphocytotoxicity assays. Class II MHC antigens were further studied by polymerase chain reaction (PCR) amplification of HLA-DRB1, DQA, and DQB genes and allele-specific oligonucleotide hybridization. For comparison purposes, we used results obtained from a group of 100 ethnically matched healthy individuals. RESULTS: We found that all eight patients had the HLA-DR3/DR4 phenotype; all HLA-DR3 haplotypes were HLA-DRB1*0301, DQA1*0501, and DQB1*0201, whereas half of the HLA-DR4 haplotypes were from the DRB1*0401 subtype and the other half were DRB1 *0407. CONCLUSIONS: These results suggest that, in Mexicans, the genetic susceptibility for the development of PG is strongly influenced by the genetic admixture of Caucasian origin, and the role of class II MHC antigens in the pathophysiology of this disease is confirmed.
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Antígenos de Histocompatibilidad Clase II/genética , Penfigoide Gestacional/etnología , Penfigoide Gestacional/genética , Adolescente , Adulto , Femenino , Técnica del Anticuerpo Fluorescente Directa , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Edad Gestacional , Antígenos de Histocompatibilidad Clase I/genética , Prueba de Histocompatibilidad , Humanos , México/etnología , Penfigoide Gestacional/patología , Fenotipo , Reacción en Cadena de la Polimerasa , Embarazo , Piel/patologíaRESUMEN
Skin care of the neonate is a very important issue, especially if the infant is either premature or is in critical condition. Guidelines for skin care put special emphasis on the skin barrier properties, transcutaneous absorption, and transepidermal water losses of the skin. The main objective of this article is to give general skin care guidelines for full-term newborn and premature infants, whether in the delivery room, the intensive care unit, or at home. These guidelines are directed to medical staff and nurses with a brief summary for parents.
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Recién Nacido/fisiología , Enfermería Neonatal/métodos , Cuidados de la Piel/métodos , Fenómenos Fisiológicos de la Piel , Humanos , Guías de Práctica Clínica como AsuntoRESUMEN
OBJECTIVE: To improve understanding of the causes of morbidity and mortality among critically ill children in the countries studied. DESIGN: Survey of hospital records between 1992 and 1994. SETTING: Six pediatric intensive care units (ICUs) (four ICUs in Mexico City and two ICUs in Ecuador). PATIENTS: Consecutive patients (n = 1,061) admitted to the units studied. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The mortality rate for low-risk patients (pediatric Risk of Mortality [PRISM] score of < or = 10, n = 701) was more than four times the rate predicted by the PRISM score (8.1% vs. 1.8%, p < .001), with an additional 11.3% of this group incurring major morbidity. The mortality rate for moderate-risk patients (PRISM scores of 11 to 20, n = 232) was more than twice predicted (28% vs. 12%, p < .001). For low-risk patients, death was significantly associated with tracheal intubation, central venous cannulation, pneumonia, age of < 2 months, use of more than two antibiotics, and nonsurgical diagnosis (after controlling for PRISM score). Central venous cannulation and tracheal intubation in the lower-risk groups were performed more commonly in units in Mexico than in one comparison unit in the United States (p < .001). CONCLUSIONS: For six pediatric ICUs in Mexico and Ecuador, mortality was significantly higher than predicted among lower-risk patients. Tracheal intubation, central catheters, pneumonia, sepsis, and nonsurgical status were associated with poor outcome for low-risk groups. We speculate that reducing the use of invasive central catheters and endotracheal intubation for lower-risk patients, coupled with improved infection control, could lower mortality rates in the population studied.
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Enfermedad Crítica/terapia , Mortalidad Hospitalaria , Unidades de Cuidado Intensivo Pediátrico/normas , Evaluación de Resultado en la Atención de Salud , Índice de Severidad de la Enfermedad , Preescolar , Cuidados Críticos , Enfermedad Crítica/mortalidad , Ecuador , Humanos , Lactante , México , Oportunidad Relativa , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de RiesgoRESUMEN
Interactions between leukocytes and endothelial cells, particularly in the microvasculature, are important for the initiation and regulation of tissue inflammation. These interactions are regulated by the recognition of specific cell adhesion molecules (CAM) on both leukocytes and endothelial cells. In this study, we examined the modulation of cell surface expression of MHC antigens and the CAM intercellular adhesion molecule 1 (ICAM-1), lymphocyte function antigen 3 (LFA-3), and CD44 on human dermal microvascular endothelial cells (HDMEC) both grown in monolayers and differentiated into capillary-like structures on the basement membrane-like substrate matrigel. HDMEC grown in monolayers or differentiated on matrigel express comparable cell surface MHC class I, LFA-3, CD44, and ICAM-1. ICAM-1, but not LFA-3 or CD44, was increased in expression in a dose- and time-dependent manner by interleukin 1 (IL-1) alpha, tumor necrosis factor (TNF) alpha, lipopolysaccharide (LPS), or interferon (IFN) gamma. Comparable upregulation was observed both in cells grown in monolayers and cells differentiated on matrigel. IL-1 alpha, TNF alpha, and LPS increased ICAM-1 expression on average 100-200% whereas IFN gamma was somewhat less potent. Comparative studies with human umbilical vein endothelial cells (HUVEC) demonstrated consistently lower levels of ICAM-1 expression on HUVEC, but greater increases after cytokine stimulation. Pretreatment with dexamethasone or transforming growth factor (TGF) beta did not affect baseline expression of ICAM-1 or inhibit upregulation of ICAM-1 on HDMEC by IL-1 alpha, TNF alpha, LPS, or IFN gamma. Both IFN gamma and TNF alpha, but not IL-1 alpha increased MHC class I expression, whereas only IFN gamma induced the expression of HLA-DR on HDMEC. The effect of IL-1 alpha, TNF alpha, or IFN gamma was inhibited by antibody to the specific cytokine, but was unaffected by antibody to other cytokines. Additionally, IFN alpha or beta inhibited upregulation of HLA-DR by IFN gamma, but had no effect on the increased MHC class I or ICAM-1 expression mediated by this cytokine. These data demonstrate that the expression of CAM and MHC antigens on small vessel-derived endothelial cells is different from that observed on large-vessel HUVEC, is regulated by the presence of multiple cytokines operating via distinct pathways, and the expression and regulation of these proteins appear to be similar on cells that have been grown in monolayers to those morphologically differentiated into blood vessel-like structures.
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Moléculas de Adhesión Celular/fisiología , Endotelio Vascular/citología , Antígenos HLA/fisiología , Moléculas de Adhesión Celular/metabolismo , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , División Celular/efectos de los fármacos , División Celular/fisiología , Células Cultivadas , Dexametasona/farmacología , Endotelio Vascular/inmunología , Endotelio Vascular/fisiología , Antígenos HLA/metabolismo , Antígenos HLA-DR/metabolismo , Humanos , Interferón gamma/farmacología , Interleucina-1/farmacología , Complejo Mayor de Histocompatibilidad/fisiología , Piel/irrigación sanguínea , Factor de Crecimiento Transformador beta/farmacología , Factor de Necrosis Tumoral alfa/farmacología , Regulación hacia Arriba/fisiologíaRESUMEN
Recently it has become recognized that cell adhesion is critical in many different cellular functions. The proteins involved in the cell-cell or cell-matrix interactions are known as cell adhesion molecules (CAMs). This article reviews some of the most important CAMs and emphasizes their importance in dermatology and in skin diseases.
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Moléculas de Adhesión Celular/fisiología , Humanos , Enfermedades de la Piel/patología , Enfermedades de la Piel/fisiopatologíaRESUMEN
Seventy-two patients from one month to 15 years of age that according with the Modificated criterion of multiple organ failure (MCMOF) had two or more organ failures were studied. They were divided into two groups: Group I consisted of 55 patients that survived and group II of 17 patients that died. In both groups, the MCMOF was determinated upon admission and discharge, as well as the maximum obtained during the evolution. The comparison of both groups, with respect to the number of organic failures presented and the points of MCMOF showed highly significant differences with p less than 0.001, found in group I: 1.27 +/- 0.96 organ failures and a value of 4.84 +/- 2.92 of the MCMOF and in the group II: 3.84 +/- 1.59 organ failures and 25.68 +/- 7.57 points of the MCMOF respectively. The comparison between the number of organic failures at admission and discharge showed significant differences in both groups, having the tendency to decrease in group I from 1.87 +/- 1.01 to 0.56 +/- 0.60 and in the group II to increase from 3.41 +/- 1.46 to 4.35 +/- 1.45. The same phenomenon was observed for the values of the MCMOF with a qualification of 7.72 +/- 5.36 to 1.87 +/- 1.82 in a group I and from 18.94 +/- 10.31 to 33.38 +/- 8.27 in group II. Spearman correlation coeficient between the number of organic failures and values of the MCMOF showed and r = 0.99 and equivalent p less than 0.001, highly significant.