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1.
Phys Rev E ; 106(1): L012201, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35974581

ABSTRACT

The interaction of light beams with helical defects in optical materials generates optical vortices. Understanding and manipulating the dynamics of helical defects allows for the creation of versatile sources of optical vortex beams. Using a magnetic ring on a nematic liquid crystal cell, we trapped helical defects identified as matter vortices. We observe oscillatory rotating and beating matter vortices by applying a low-frequency voltage. Experimentally, we determine the region of parameters where these vortices are observed. The amplitude of oscillatory rotating vortices decays with the inverse of the voltage frequency. We propose an adequate amplitude equation, which allows us to describe the vortex dynamics; theoretical findings have a qualitative agreement with the experimental observations.

2.
Waste Manag ; 126: 643-651, 2021 May 01.
Article in English | MEDLINE | ID: mdl-33872973

ABSTRACT

Conventional municipal waste management systems based on collecting and storing waste for future management are cost-effective and flexible. These systems present significant problems such as odours, plagues and hygiene problems caused by their storage and greenhouse gas emissions from garbage trucks used for the transport of waste. The Automated Waste Collection System (AWCS) and Automated Vacuum Waste Collection (AVWC) systems, in which waste is transported directly underground to the processing plants, are efficient collection systems and respectful of the environment as alternatives to traditional systems. The pneumatic system reduces the value of the per capita generation of general waste. The present study explains the origin of pipe failure in two different AWCS factories, as well as the identification of the failure phenomena. To carry out the study, a classification of 90 failure cases by primary cause was performed, followed by recommendations to avoid these failures in the future. Moreover, a computational fluid dynamics (CFD) simulation was performed in order to help in the failure determination and the key recommendations to avoid the most common and frequent failures.


Subject(s)
Garbage , Greenhouse Gases , Refuse Disposal , Waste Management , Vacuum
4.
Gastroenterol. latinoam ; 31(2): 98-106, 2020. tab, ilus, graf
Article in Spanish | LILACS | ID: biblio-1292434

ABSTRACT

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that survives in gastric acidity. Approximately 50% of the world population is a carrier of this infection and the prevalence is higher in African and Latin American populations. The clinical manifestations associated with this infection are gastritis, peptic ulcers, MALT lymphoma, gastric cancer (GC), and other extra-digestive pathologies. Chronic H. pylori infection is the most important risk factor for GC development. There are several diagnostic methods to detect H. pylori infection. The most widely used invasive methods are the rapid urease test and Giemsa staining in gastric biopsies. Culture and molecular techniques are very useful for the study of H. pylori presence and antibiotic resistance, but they are not easily available in health centers. The most widely used non-invasive methods are the urea breath test and bacterial antigens in stools. Serological studies are used for population studies. The use and indication of the diagnostic method for detecting H. pylori infection will depend on the clinical manifestations, risk factors for GC, and the age of the patient.


Helicobacter pylori (H. pylori) es una bacteria Gram negativa que sobrevive a la acidez gástrica. Se estima que aproximadamente el 50% de la población mundial es portadora de esta infección, siendo mayor la prevalencia en poblaciones africanas y latinoamericanas. Entre las manifestaciones clínicas asociadas a esta infección se encuentra gastritis, úlceras pépticas, linfoma MALT, cáncer gástrico y otras patologías extradigestivas. La infección crónica por H. pylori es el factor de riesgo más importante para el desarrollo de CG. Existen diversos métodos diagnósticos para detectar la infección por H. pylori, los métodos invasivos más utilizados son la prueba rápida de ureasa y tinción de Giemsa en biopsias gástricas. El cultivo y las técnicas moleculares son de gran utilidad para el estudio de presencia de H. pylori y estudios de resistencia antibiótica, pero suelen estar poco disponibles en los centros de atención en salud. Los métodos no invasivos más utilizados son la prueba de aire espirado con urea marcada y antígeno bacteriano en deposiciones. Los estudios serológicos son utilizados para estudios poblacionales. El uso e indicación de cada uno de los métodos de diagnóstico para la detección de infección por H. pylori, dependerá de las manifestaciones clínicas, los factores de riesgo de CG y la edad del paciente.


Subject(s)
Humans , Helicobacter pylori , Helicobacter Infections/diagnosis , Evidence-Based Medicine
6.
Ecotoxicol Environ Saf ; 169: 418-424, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30469027

ABSTRACT

Toxic metal content were measured in samples of mollusc Concholepas concholepas obtained from the Chilean coast. Samples were collected during two periods, one before and one after the earthquake-tsunami which occurred in the Maule Region, Chile, February 27th, 2010 as a result of an earthquake with a magnitude of 8.8. Quantification of toxic metals in samples of hepatopancreas and muscle tissue was performed using flame atomic absorption spectroscopy. The analytical methodology was validated with certified reference material. The content means measured in muscle tissue for January 2010 were Cu: 10.3; Cr: 0.7; Cd: < 0.1; Mn: 3.6 and Zn: 38.6 µg g-1 (dry weight). For October 2014, the means were Cu: 8; Cr: 2.4; Cd: < 0.1; Mn: 5.6 and Zn: 45.4 µg g-1 (dry weight). In hepatopancreas tissue, the content means were Cu: 14.8; Cr: 2.4; Cd: 246.2; Mn: 4.4 and Zn: 1552.9 µg g-1 (dry weight). For October 2014, the means were Cu: 53.7; Cr: 3.5; Cd: 118; Mn: 13.4 and Zn: 1352.3 µg g-1 (dry weight). Cd, Cr, Cu, Mn and Zn content in the samples of hepatopancreas were generally higher than those recorded in muscle tissue however they were not always statistically significant. Statistical analysis showed that Cu and Mn content in the post-tsunami period increased in the hepatopancreas tissue. The concentrations of Cd, Cr, Cu, Mn, and Zn measured in the muscular tissue (edible part) of the species Conchalepas concholepas, were lower than the maximum contents allowed by the current legislation (FAO/WHO, 2004; EU, 2001) and its consumption is not a risk to human health.


Subject(s)
Earthquakes , Environmental Monitoring/methods , Gastropoda/drug effects , Metals, Heavy/analysis , Muscles/drug effects , Tsunamis , Animals , Chile , Gastropoda/chemistry , Humans , Muscles/chemistry , Spectrophotometry, Atomic
8.
Gastroenterol. latinoam ; 30(supl.1): S18-S25, 2019. ilus, tab, graf
Article in Spanish | LILACS | ID: biblio-1116305

ABSTRACT

Helicobacter pylori (H. pylori) is a gram negative bacteria that survives in the gastric acid environment. The infection is acquired mainly during childhood. Fifty to 70% of adult population has the infection. However, in the last 10 year, a decrease in the prevalence of this infection has been observed in all age groups, in particular in pediatric population and elderly patients over 60 years old. The evolution of the infection depends on bacterial factors (virulence and toxins) and host immune response. People infected mainly develop gastrointestinal diseases such as gastritis, peptic ulcer and MALT lymphoma. H. pylori infection is the main risk factor of gastric cancer and for that reason, the eradication is recommended if H. pylori has been detected through invasive or non-invasive tests. Among children, eradication is not recommended unless there is a clinical manifestation that merits. H. pylori eradication is recommended in symptomatic adults and there is a controversy about massive eradication in asymptomatic population due to the risk of development of antibiotic resistance. Treatment is based on the use of proton pump inhibitors (PPI) associated to antibiotics, that should be chosen taking into account the increasing antibiotic resistance, and local availability. Clarithromycin (CLA) and levofloxacin resistance is increasingly high, and CLA-free quadruple therapy schemes are currently recommended for first-line therapy. H. pylori eradication must be confirmed with invasive or non-invasive tests. Second-line therapy based on antibiotics not previously used, PPI high doses and bismuth is recommended.


Helicobacter pylori (H. pylori) es una bacteria gramnegativa que sobrevive en el medio ácido gástrico. La infección se adquiere principalmente en la niñez. Un 50 a 70% de la población adulta es portadora, pero en los últimos 10 años, se ha observado una disminución en la prevalencia de infección en todos los grupos etarios, en particular en población pediátrica y mayores de 60 años. La evolución de la infección depende de factores propios de la bacteria (virulencia, toxinas) y de la respuesta inmune del huésped. Los individuos infectados desarrollan principalmente patologías gastrointestinales como gastritis, úlcera péptica y linfoma MALT. La infección por H. pylori es el principal factor de riesgo del cáncer gástrico por lo que se recomienda su erradicación en caso de haberse detectado mediante test invasivo o no invasivo. En niños, no es recomendable la erradicación a menos que exista una manifestación clínica que lo amerite. Se recomienda su erradicación en adultos sintomáticos y existe controversia respecto a la erradicación masiva en población asintomática debido al riesgo de desarrollar resistencia antibiótica. El tratamiento se basa en el uso de inhibidores de la bomba de protones asociado a antibióticos, los cuales deben ser escogidos teniendo en cuenta la tasa de resistencia antimicrobiana y disponibilidad local. La resistencia a claritromicina (CLA) y levofloxacino es creciente, por lo que se recomienda el uso de esquemas de cuadriterapia libre de CLA en esquemas de primera línea. Se recomienda confirmar su erradicación con test no invasivos y retratar con esquema de segunda línea con antibióticos no utilizados previamente, asociado a dosis altas de inhibidores de bomba de protones y sales de bismuto.


Subject(s)
Humans , Child , Adult , Helicobacter Infections/drug therapy , Remission Induction , Helicobacter pylori/drug effects , Helicobacter pylori/pathogenicity , Helicobacter Infections/diagnosis , Helicobacter Infections/physiopathology , Age Factors , Clarithromycin/therapeutic use , Drug Resistance, Bacterial/drug effects , Drug Therapy, Combination , Proton Pump Inhibitors/therapeutic use , Levofloxacin/therapeutic use
9.
Transplant Proc ; 50(5): 1489-1495, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29880376

ABSTRACT

BACKGROUND: Heart transplantation (HT) is regarded as the treatment of choice for end-stage heart failure (ESHF) patients. Severe acute kidney injury (AKI) after HT is a frequent clinical problem with devastating consequences for HT recipients. METHODS: Data from 112 ESHF patients undergoing HT in 2010-2015 were retrospectively reviewed. The primary end point was the development of AKI stage III, and secondary outcomes were in-hospital and 1-year mortality according to Kidney Disease Improving Global Outcomes criteria. RESULTS: In total, 81 patients (72.3%) developed AKI, of which 33 (29.4%) developed AKI stage I, 18 (16%) stage II, and 30 (26.7%) stage III; within this group, 27 recipients (24%) required renal replacement therapy (RRT). Overall hospital mortality was 14%. However, when stratifying by AKI stage, hospital mortality increased from 0% to 46% comparing recipients without AKI and those with AKI stage III, respectively (P = .001). In the same way, 1-year mortality increased from 6% to 53% for recipients without AKI compared with those who developed AKI stage III (log-rank test for trend: P = .001). Recipients that required RRT had a 1-year mortality of 59.2% compared with 5.8% in those without RRT requirement. CONCLUSIONS: The findings indicate that AKI stage III is common after HT and adversely affects early and late mortality. Clinical variables together with perioperative hemodynamic assessment could add more powerful prognostic information to predict severe AKI before HT and therefore evaluate potential heart-kidney recipients.


Subject(s)
Acute Kidney Injury/epidemiology , Acute Kidney Injury/etiology , Heart Transplantation/adverse effects , Heart Transplantation/mortality , Adult , Cohort Studies , Female , Hospital Mortality , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Prognosis , Proportional Hazards Models , Retrospective Studies
10.
Dalton Trans ; 47(6): 1808-1818, 2018 Feb 06.
Article in English | MEDLINE | ID: mdl-29322149

ABSTRACT

Main group element coordination polymers (MGE-CPs) are important compounds for the development of multifunctional materials. However, there has been a shortage of studies regarding their structural, optical, catalytic, mechanical, and antibacterial properties. This work presents an exhaustive study of a set of crystalline MGE-CPs obtained from bismuth and indium metals and iminodiacetate, 1,2,4,5-benzenetetracarboxylate, and 2,2'-bipyridine as building blocks. An in-depth topological analysis of the networks was carried out. Additionally, nanoindentation studies were performed on two representative low-dimensional compounds in order to find the relationships between their structural features and their intrinsic mechanical properties (hardness and elasticity). The solid-state photoluminescence (SSPL) properties were also studied in terms of excitation, emission, lifetimes values, and CIE chromaticites. Moreover, the heterogeneous catalytic activities of the compounds were evaluated with the cyanosilylation reaction using a set of carbonylic substrates under solvent-free conditions. Finally, the inhibitory effect of the Bi-CPs on the growth of microorganisms such as Escherichia coli, Salmonella enterica serovar Typhimurium, and Pseudomonas aeruginosa, which are associated with relevant infectious diseases, is reported.

11.
Gastroenterol. latinoam ; 28(4): 225-230, 2017. ilus, graf
Article in Spanish | LILACS | ID: biblio-1119665

ABSTRACT

Background: Non-alcoholic fatty liver disease (NAFLD) is a spectrum of hepatic lesions, ranging from benign intrahepatic lipid accumulation (steatosis) to progressive non-alcoholic steatohepatitis, in absence of other known secondary causes. Both insulin resistance and oxidative stress have been involved in NAFLD development and progression and, therefore, insulin-sensitizers and/or antioxidants have been targets of different therapeutic agents. Some natural compounds such as Aristotelia chilensis have a high content of polyphenols, which are known for their antioxidant and anti-inflammatory properties. Objective: To assess the effect of a purified anthocyanin-rich extract of maqui (Aristotelia chilensis) on experimental model of NAFLD. Methods: C57BL6 mice were separated in four experimental groups (n = 4-10) and fed a control diet (chow) or a high fat diet (HFD) with or without a purified anthocyanin-rich extract of Aristotelia chilensis (ACnE) (400 mg/kg/day diluted in drinking water). The hepatic effects of HFD were assessed measuring serum levels of glucose and aminotransferases, hepatic histology and triglycerides. Results: HFD diet induced an increase in hepatic triglycerides and histological NAFLD. Administration of ACnE did not affect serum aminotransferases, hepatic triglycerides, liver weight or histological NAFLD. Conclusion: Administration of an ACnE showed no effects on NAFLD in the HFD experimental model.


Introducción: El hígado graso no alcohólico (HGNA) constituye un espectro de lesiones hepáticas, desde la acumulación lipídica intrahepática benigna (esteatosis) hasta la esteatohepatitis no-alcohólica progresiva, en ausencia de causas secundarias conocidas. En el desarrollo y la progresión del HGNA se ha involucrado la resistencia a insulina y el estrés oxidativo y, por lo tanto, insulino-sensibilizantes y antioxidantes han sido blancos de diferentes agentes terapéuticos. Algunos compuestos naturales como la Aristotelia chilensis (maqui) tienen un alto contenido de polifenoles, los que presentan propiedades antiinflamatorias y antioxidantes. Objetivo: Evaluar el efecto de un extracto purificado rico en antocianinas (EACn) del fruto del maqui (Aristotelia chilensis) sobre la esteatosis, en un modelo experimental de HGNA. Métodos: Los ratones fueron distribuidos en 4 grupos (n = 4-10). Dos alimentados con una dieta estándar (grupo control) y dos con una dieta alta en grasa- high fat diet (grupo HFD). Un grupo control y uno HFD recibieron además 400 mg/kg/día de EACn (grupo EACn). Se determinaron los niveles séricos de aminotransferasas y glucosa; se evaluó la histología hepática y el contenido hepático de triglicéridos. Resultados: HFD indujo aumento de triglicéridos hepáticos e HGNA histológico. La administración de EACn no modificó las transaminasas séricas, los triglicéridos hepáticos, el peso del hígado ni el HGNA histológico. Conclusiones: La administración de un EACn no mostró efectos en el modelo experimental de HGNA inducido por una dieta alta en grasa.


Subject(s)
Animals , Mice , Plant Extracts/metabolism , Polyphenols/metabolism , Non-alcoholic Fatty Liver Disease/diet therapy , Plant Extracts/chemistry , Fatty Liver/diet therapy , Polyphenols/chemistry , Liver/pathology , Antioxidants/therapeutic use
12.
Leukemia ; 28(6): 1242-51, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24304937

ABSTRACT

The complex chromosomal aberrations found in therapy-related acute myeloid leukemia (t-AML) suggest that the DNA double-strand break (DSB) response may be altered. In this study we examined the DNA DSB response of primary bone marrow cells from t-AML patients and performed next-generation sequencing of 37 canonical homologous recombination (HR) and non-homologous end-joining (NHEJ) DNA repair genes, and a subset of DNA damage response genes using tumor and paired normal DNA obtained from t-AML patients. Our results suggest that the majority of t-AML patients (11 of 15) have tumor-cell intrinsic, functional dysregulation of their DSB response. Distinct patterns of abnormal DNA damage response in myeloblasts correlated with acquired genetic alterations in TP53 and the presence of inferred chromothripsis. Furthermore, the presence of trisomy 8 in tumor cells was associated with persistently elevated levels of DSBs. Although tumor-acquired point mutations or small indels in canonical HR and NHEJ genes do not appear to be a dominant means by which t-AML leukemogenesis occurs, our functional studies suggest that an abnormal response to DNA damage is a common finding in t-AML.


Subject(s)
Biomarkers, Tumor/genetics , Bone Marrow/pathology , DNA Breaks, Double-Stranded , DNA Damage/genetics , Granulocyte Precursor Cells/pathology , Leukemia, Myeloid, Acute/pathology , Leukemia, Myeloid, Acute/therapy , Animals , Chromosomes, Human, Pair 8/genetics , Comet Assay , Comparative Genomic Hybridization , DNA Repair/genetics , Flow Cytometry , Gene Expression Profiling , Histones/metabolism , Humans , Leukemia, Myeloid, Acute/genetics , Mice , Mice, Inbred C57BL , Mutation/genetics , Oligonucleotide Array Sequence Analysis , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Tumor Suppressor Protein p53/genetics
13.
Rev. chil. radiol ; 20(2): 75-80, 2014. ilus, tab
Article in Spanish | LILACS | ID: lil-716996

ABSTRACT

El objetivo de este estudio es desarrollar y validar una pauta para la evaluación del proceso de enseñanza clínica en radiología; Medicina Universidad Católica, Radiología 32 ítems (MEDUC-RX32). Se utilizó metodología mixta para el desarrollo del instrumento: dos entrevistas grupales (residentes y docentes) y una individual a un jefe de programa de radiología. Utilizando técnica Delfi modificada para lograr acuerdo, un panel de validez nacional evaluó la importancia de cada ítem. El panel Delfi refinó el instrumento de 88 a 32 ítems luego de dos rondas. La pauta final fue piloteada en 55 residentes del programa. El instrumento definitivo presenta alta confiabilidad (coeficiente alfa de Cronbach de 0,957). El promedio de las evaluaciones del desempeño de los docentes fue de 6,23 mas menos 0,8 (escala Likert 0 a 7) constituyéndose en una pauta válida y confiable para la evaluación de docentes de programas de la especialidad de radiología en países de habla hispana.


The objective of this study is to develop and validate a guideline for the evaluation of the clinical teaching process in radiology; Catholic University Medical School, Radiology 32 items (MEDUC-RX32). A mixed methodology was used for the development of the questionnaire; two interview groups (residents and faculty) and one individual to a radiology program head. Using a modified Delphi technique to reach an agreement, a national validity panel assessed the importance of each item. The Delphi panel refined the questionnaire from 88 to 32 items after two rounds. The final guideline was perfomed in 55 residents of the program. The final instrument shows high reliability (Cronbach's alpha coefficient of 0.957). The average performance evaluations of teachers was 6.23 ± 0.8 (Likert scale 0 to 7) becoming a valid and reliable guideline for teacher evaluation of programs in the specialty of radiology, in Spanish speaking countries.


Subject(s)
Surveys and Questionnaires , Faculty , Educational Measurement/methods , Radiology , Chile , Education, Medical , Qualitative Research
14.
Farm Hosp ; 37(2): 95-102, 2013.
Article in Spanish | MEDLINE | ID: mdl-23789753

ABSTRACT

OBJECTIVE: To know the usage, effectiveness, and toxicity associa ted to Sorafenib treatment in cancer patients at a general hospital. METHODS: Observational, retrospective, and longitudinal study on the usage, effectiveness and toxicity associated to Sorafenib. Cancer patients at a general university hospital initiating treatment with Sorafenib were included between January of 2007 and December of 2010, with an extended follow-up period up to June of 2012. RESULTS: 31 patients started the treatment (mean age 61.6 years; 67.7% males). 83.87% received a monotherapy regimen with fixed doses of 400 mg b.i.d., whereas 5 patients required dose adjustment due to poor gastrointestinal tolerance and skin toxicity. At the end of the study, 3 patients were still alive and kept on receiving the treatment, 27 withdrew from the therapy, and 1 pa - tient was lost to follow-up. The pathologies treated with Sorafenib were hepatocarcinoma (38.7%), advanced renal cancer (35.5%), melanoma (9.7%), thyroid cancer (12.9%), and gastrointestinal stromal tumor (3.2%). The median overall survival was 524 days for hepatocarcinoma and 217 days for renal cancer. Adverse reactions with Sorafenib were observed in 41.9% of the patients. CONCLUSIONS: This study reveals that Sorafenib is effective in patients with hepatocarcinoma and renal cancer, essentially depending on the baseline clinical status of the patients. Sorafenib may be associated with the occurrence of adverse events, mainly gastrointestinal and cutaneous, requiring dose adjustment and treatment withdrawal in some cases.


Objetivo: Conocer la utilización, efectividad y toxicidad asociada al tratamiento con sorafenib en los pacientes oncológicos de un hospital general. Métodos: Estudio observacional, retrospectivo y longitudinal de utilización, efectividad y toxicidad asociada a sorafenib. Se incluyeron los pacientes oncológicos de un hospital general universitario, que iniciaron tratamiento con sorafenib entre Enero 2007 y Diciembre 2010, ampliando el periodo de seguimiento hasta junio de 2012. Resultados: Iniciaron tratamiento 31 pacientes (edad media 61,6 años, 67,7% varones). En todos se utilizó un régimen de monoterapia, empleándose dosis fijas de 400 mg cada 12 horas en el 83,87%, mientras que 5 pacientes precisaron ajuste de dosis por mala tolerancia gastrointestinal y toxicidad cutánea. Al finalizar el estudio, 3 pacientes continuaban vivos y mantuvieron el tratamiento, 27 pacientes lo suspendieron y en 1 paciente se perdió el seguimiento. Las patologías tratadas con sorafenib fueron hepatocarcinoma (38,7%), cáncer renal avanzado (35,5%), melanoma (9,7%), caeacute;ncer de tiroides (12,9%) y tumor del estroma gastrointestinal (3,2%). La mediana de supervivencia global fue de 524 días para hepatocarcinoma y de 217 días para cáncer renal. Se observaron reacciones adversas a sorafenib en el 41,9% de los pacientes. Conclusiones: Este estudio revela que sorafenib es eficaz en los pacientes con hepatocarcinoma y cáncer renal, dependiendo fundamentalmente de la situación clínica inicial de los pacientes. Sorafenib es responsable de la aparición de efectos secundarios, fundamentalmente de tipo gastrointestinal y cutáneo, que requirieron ajuste de dosis y suspensión del tratamiento en algunos casos.


Subject(s)
Antineoplastic Agents/therapeutic use , Neoplasms/drug therapy , Niacinamide/analogs & derivatives , Phenylurea Compounds/therapeutic use , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/adverse effects , Female , Humans , Longitudinal Studies , Male , Middle Aged , Niacinamide/adverse effects , Niacinamide/therapeutic use , Phenylurea Compounds/adverse effects , Retrospective Studies , Sorafenib
15.
Gastroenterol. latinoam ; 22(4): 296-301, oct.-dic. 2011. ilus, tab, graf
Article in Spanish | LILACS | ID: lil-661633

ABSTRACT

Non-alcoholic fatty liver (NAFLD) is a clinical entity whose importance has been increasing, because of its potential progression to chronic liver disease. The alteration of bile secretory function may be a relevant factor of hepatic injury in NAFLD. Objectives: To assess basal bile secretory function and protein mass of three major hepatobiliary transporters in an experimental NAFLD model. Materials and Methods: The bile secretory function was determined by conventional techniques in Sprague-Dawley control rats fed with a choline-deficient diet (CDD) for 8 weeks. Protein mass of Ntcp, Bsep and Mrp2 was measured by western blot. Results: An impaired bile secretory function was observed in rats fed with DDC (reduction of bile flow and secretion of bile acids and organic anions). In addition, DDC fed rats showed higher levels of serum aminotransferases. Ntcp protein mass decreased in rats with DDC, while Bsep and Mrp2 did not show quantitative variations in this experimental model. Conclusions: In this experimental model of NAFLD an impaired bile secretory function was observed, determining a cholestatic pattern. The decrease in Ntcp protein mass with unaltered Bsep and Mrp2 protein mass, associated with a significant decrease in bile secretion suggests a functional impairment of these transporters in rats fed with DDC diet.


El hígado graso no alcohólico (HGNA) es una entidad clínica de importancia creciente por su potencial progresión a daño hepático crónico. La alteración de la función secretora biliar puede ser un factor relevante en el daño o lesión hepática asociada al HGNA. Objetivos: Evaluar la función secretora biliar basal y los niveles de expresión proteica de tres de los principales transportadores hepatobiliares en un modelo de HGNA experimental. Materiales y Métodos: La función secretora biliar fue determinada por técnicas convencionales en ratas Sprague-Dawley control y alimentadas con una dieta deficiente en colina (DDC) durante 8 semanas. Los niveles de expresión proteica de Ntcp, Bsep y Mrp2 fueron cuantificados por western blot. Resultados: Se observó un deterioro de la función secretora biliar en las ratas alimentadas con DDC (reducción del flujo biliar y de secreción de ácidos biliares y aniones orgánicos). Además, las ratas con DDC presentaron niveles más altos de transaminasas séricas. Los niveles de expresión proteica de Ntcp disminuyeron en las ratas con DDC, mientras que Bsep y Mrp2 no presentaron variaciones cuantitativas en este modelo experimental. Conclusiones: En este modelo de HGNA experimental se observó una función secretora biliar alterada, determinando un patrón colestásico. La disminución de los niveles de expresión proteica de Ntcp junto con la mantención de Bsep y Mrp2, asociados a una disminución significativa de la secreción biliar, sugiere un deterioro funcional de estos transportadores en ratas alimentadas con dieta DDC.


Subject(s)
Animals , Rats , Bile , Fatty Liver/physiopathology , Fatty Liver/metabolism , Cholestasis/metabolism , Choline Deficiency , Liver/pathology , Multidrug Resistance-Associated Proteins/metabolism , Rats, Sprague-Dawley , Organ Size , Organic Anion Transporters, Sodium-Dependent/metabolism , Blotting, Western , Bile Acids and Salts/metabolism
16.
Horm Metab Res ; 39(1): 14-9, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17226108

ABSTRACT

Inositol phosphoglycan-like compounds are produced by the hydrolysis of the membrane bound glycosyl phosphoinositides. Besides being short term mediators of insulin action, they inhibit peroxidases and catalase, increasing the concentration of cellular hydrogen peroxide. Although high concentrations of hydrogen peroxide are toxic, moderate increases of its basal level are signals for different metabolic pathways. The inhibitor, localized in the cytosol of the cell, acts on peroxidases and catalase of the same tissue (homologous action) and of other tissues or organisms (heterologous action). The inositol phosphoglycan-like compound inhibits peroxidases with different prosthetic groups, i.e. containing iron such as: thyroid peroxidase, lactoperoxidase, horseradish peroxidase, soy bean peroxidase; and containing selenium such as glutathione peroxidase and 2-cys peroxiredoxin with no prosthetic group. Besides peroxidases, the inositol phosphoglycan-like compound inhibits catalase, another heme enzyme. The inhibition kinetics demonstrates a noncompetitive effect. The site of action is not the prosthetic group, given that the inhibitor does not produce any effect on the peak in the Soret region in the presence or absence of hydrogen peroxide. In conclusion, the inositol phosphoglycan-like compound is the general inhibitor of peroxidases and catalase involved in the modulation of hydrogen peroxide level that acts in different metabolic pathways as a signal transducer.


Subject(s)
Catalase/antagonists & inhibitors , Hydrogen Peroxide/metabolism , Inositol Phosphates/pharmacology , Peroxidase/antagonists & inhibitors , Polysaccharides/pharmacology , Animals , Cattle , Cells, Cultured , Enzyme Inhibitors/pharmacology , Horseradish Peroxidase/antagonists & inhibitors , Iodide Peroxidase/antagonists & inhibitors , Lactoperoxidase/antagonists & inhibitors , Soybean Proteins/antagonists & inhibitors , Glycine max/enzymology
17.
Rev. chil. ultrason ; 10(1): 4-10, 2007. ilus, tab
Article in Spanish | LILACS | ID: lil-467659

ABSTRACT

La fisura labial, término actualmente utilizado como sinónimo leporino, es una malformación congénita caracterizada por fisura del labio superior, que puede o comprometer paladar secundario denominándose entonces fisura labiopalatina, pudiendo ser la fisura labial tanto unilateral como bilateral y la palatina, medial. En la formación de la cara participa principalmente el quinto arco faríngeo, que mediante la formación de distintas prolongaciones hacia anterior finaliza con la formación de ésta. La etiopatogenia de este defecto aún no está bien precisada permaneciendo en constante estudio y progresivo avance. Se han descrito más de 180 síndromes asociados con fisuras labiopalatinas, representando aproximadamente el 10 por ciento de los casos, el 90 por ciento restante estaría dado por un patrón hereditario multifactorial donde los factores ambientales jugarían un rol importante. Con el avance de la tecnología y la modernización de los equipos ultrasonográficos se logra visualización completa del macizo facial, con un 90 por ciento de éxito entre las semanas 16 y 24 de gestación en un plano axial y coronal, con ultrasonografía 2D en comparación con la 3D en algunos estudios demuestra un gran aporte de esta última en la detección de la fisura palatina, aumentando la sensibilidad y especificidad. Se analizaron 350 fichas de pacientes ingresadas y controladas por el Centro de Referencia Perinatal Oriente (CERPO) por un período comprendido entre el año 2003 y el 2006, se hallaron once casos con diagnóstico prenatal de fisura labial. Al analizar la concordancia de diagnóstico utrasonográfico con el resultado perinatal se encontró una concordancia en el 100 por ciento de los casos para fisura labial, y en concordancia con lo que se expone en la literatura, no se logró diagnosticar ninguna de las fisuras palatinas. La mortalidad de un 55 por ciento que se presentó en este análisis haría pensar que es atribuible ésta a la malformación en estudio, pero el 100 por cient...


Subject(s)
Male , Female , Pregnancy , Infant, Newborn , Infant , Child, Preschool , Adolescent , Adult , Humans , Cleft Palate , Cleft Lip/epidemiology , Cleft Lip , Cleft Palate , Genetic Predisposition to Disease , Cleft Lip/genetics , Maternal Age , Paternal Age , Pregnancy Outcome , Pregnancy Trimester, Second , Pregnancy Trimester, Third , Risk Factors , Ultrasonography, Prenatal
18.
Rev. chil. ultrason ; 9(3): 72-79, mar. 2006. ilus, tab, graf
Article in Spanish | LILACS | ID: lil-497939

ABSTRACT

Abdominal wall defects are ranking in the 4th place of congenital malformations. The most frequent ones are gastroschisis and omphalocele, which show a high perinatal mortality. Over the last 30 years, world incidence has grown. The national incidence and prevalence of these defects should be determined. Objective: The analysis of trends in clinical characteristics of these defects referred to a national centre and treated in Santiago, Chile, between March 2003 and August 2006. Method: 7 cases of omphalocele and 7 cases of gastroschisis were analysed. We studied associated risk factors, prenatal management and postnatal follow-up. Results: The average maternal age in gastroschisis was 18 and 28.4 in omphalocele. Five patients with gastroschisis were primigravida. None of the patients had a history of drugs, alcohol or tobacco intake. Six of seven of omphalocele cases we associated with other malformations, three of them were multiple malformations Cantrell type. None of the cases of gastroschisis showed any associated malformations. In six cases of omphalocele and in one case of gastroschisis fetal karyotyping was studied. Six cordocentesis and one amniocentesis were performed. Results were one Trisomy 18 (omphalocele) and six normal kariotype. In three cases of omphalocele, the babies were delivered with elective cesarean section. In three cases of omphalocele and all cases of gastroschisis, urgent Cesarean section had to be performed. There was one vaginal delivery with a stillborn (Trisomy 18). Among the gastroschisis cases and three of the omphalocele cases, four children were born prematurely. The average weight of the newborns with gastroschisis was 2.365 gr., and 2.770 gr., in omphalocele cases. The distribution by sex in gastroschisis was 6 females: 1 male, in cases of omphalocele it was 4 females: 3 males. Of all 14 cases, two died during the first hours, and one was a stillborn. In the first...


Los defectos de la pared anterior del abdomen se ubican en 4° lugar de las malformaciones congénitas, siendo los más frecuentes la gastrosquisisy el onfalocele que presentan una alta mortalidad perinatal. En los últimos 30 años se reporta un aumento de la incidencia a nivel mundial. Es importante determinar la incidencia y prevalencia nacional de estos defectos. Objetivos: Analizar tendencias en las características clínicas de los defectos de pared anterior del abdomen, derivados a un centro de referencia nacional (Centro de Referencia Perinatal Oriente, CERPO), y atendidos en su red en Santiago, Chile, entre Marzo 2003 y Agosto 2006. Método: Se analizan todos los casos encontrados en el periodo. Se trata de 7 onfaloceles y 7 gastrosquisis, factores de riesgo asociados, evolución prenatal y seguimiento postnatal. Resultados: Media de edad materna 18 años en gastrosquisis y 28.4 años en onfaloceles. Cinco de 7 pacientes con gastrosquisis eran primigestas. Ninguna paciente tiene antecedentes de consumo de drogas, alcohol ni tabaco. Malformaciones asociadas en 6 de 7onfaloceles, de las cuales 3 de 7 eran malformaciones múltiples tipo Cantrell. Ninguna gastrosquisis presentó malformaciones asociadas. Se realizaron siete cordocentesis y una amniocentesis a 6 onfaloceles y a 1 gastrosquisis resultando 1 trisomia 18 (onfalocele) y 6 cariogramas normales. Nacieron por cesárea programada 3 de 7 onfaloceles y por cesárea de urgencia 3 de 7 onfaloceles y 7 de 7 gastrosquisis. Un parto vaginal por óbito (trisomía 18). Edad gestacional al parto: 4 de 7 gastrosquisis nacieron de pretérmino: y 3 de 6 onfaloceles. Peso promedio de recién nacidos vivos con gastrosquisis:2.365 g, onfaloceles: 2.770 g. Distribución por sexo en gastrosquisis 6 femeninos / 1 masculino, en onfalocele 4 femeninos / 3 masculinos. Tres de 14 fallecieron en las primeras horas de vida o nacieron muertos. En los primeros tres meses de vida fallecieron 3 de 6 onfaloceles y 1 de...


Subject(s)
Humans , Female , Pregnancy , Infant, Newborn , Abdominal Wall/abnormalities , Abdominal Wall , Ultrasonography, Prenatal , Congenital Abnormalities/epidemiology , Chile/epidemiology , Follow-Up Studies , Gastroschisis , Hernia, Umbilical , Incidence , Prevalence , Risk Factors
19.
Rev. chil. ultrason ; 9(4): 113-126, 2006. ilus, tab
Article in Spanish | LILACS | ID: lil-471389

ABSTRACT

La malformación de Dandy Walker es una anomalía congénita caracterizada por un ensanchamiento quístico del cuarto ventrículo e hipoplasia o agenesia del vermis cerebeloso, que secundariamente produce hidrocefalia congénita e hipertensión intracraneal. La tríada característica para establecer el diagnóstico consiste en hidrocefalia, ausencia de vermis cerebeloso y quiste de la fosa posterior con comunicación con el cuarto ventrículo. Actualmente se han descrito tres variantes de esta malformación: Malformación Clásica de Dandy Walker (SDW), Hipoplasia vermis cerebeloso, y dilatación de cisterna magna (CMD). Se revisaron todos los casos de malformación de Dandy Walker controlados en Centro de Referencia Perinatal Oriente (CERPO) entre abril 2003 y septiembre 2006. Se controlaron once casos durante este período, diez de ellos con diagnóstico prenatal de alguna de las variantes de Dandy Walker (ocho casos de CMD y dos casos de SDW) y un caso con diagnóstico prenatal de agenesia del cuerpo calloso, diagnosticándose postnatalmente síndrome de Dandy Walker. A estas pacientes se les manejó en CERPO mediante seguimiento ultrasonográfico, cordocentesis para estudio de cariograma fetal, ecocardiografía, resonancia magnética fetal, consejería y apoyo psicológico. No se encontró asociación con los factores de riesgo descritos en la bibliografía. Sólo existe en un caso el antecedente de consanguinidad paterna y otro caso con antecedente de prima en primer grado materna con síndrome de Down. Destaca la alta asociación con aneuploidías (siete de los once casos, 64 por ciento): cinco casos de trisomías 18 (71 por ciento), una trisomía 21 y una translocación 6-13. Hay una alta tasa de mortalidad tanto pre como postnatal (46 por ciento), falleciendo cinco de los once casos durante la gestación o el primer año de vida. Ninguno de los casos ha requerido de manejo quirúrgico postnatal. Sólo tres casos (24 por ciento) no presentaron otra malformación asociada, todos con diagnóstico...


Subject(s)
Female , Pregnancy , Infant, Newborn , Adult , Humans , Dandy-Walker Syndrome , Ultrasonography, Prenatal , Cisterna Magna/pathology , Follow-Up Studies , Risk Factors , Referral and Consultation , Dandy-Walker Syndrome/classification , Dandy-Walker Syndrome/complications , Dandy-Walker Syndrome/therapy
20.
Rev. chil. obstet. ginecol ; 71(5): 320-326, 2006. tab, graf
Article in Spanish | LILACS | ID: lil-464215

ABSTRACT

Objetivo: Seguimiento de las cardiopatías congénitas con diagnóstico prenatal. Método: Se analizan todas las cardiopatías con diagnóstico prenatal que ingresaron al Centro de Referencia Perinatal Oriente (CERPO) entre Abril 2003 y Junio 2005. Se realiza seguimiento postnatal y se compara el pronóstico con la experiencia previamente reportada en la literatura. Resultados: Se detectaron 94 cardiopatías congénitas de las cuales 76,6 por ciento correspondían a pacientes referidas desde otras regiones del país. La edad gestacional promedio al diagnóstico fue de 32 semanas. La principal causa de derivación correspondió a sospecha en examen obstétrico ultrasonográfico de rutina (72 por ciento de los casos). En esta serie se detectaron 10 anomalías cromosómicas y 14 casos presentaron malformaciones extracardíacas asociadas. Los diagnósticos más frecuentes correspondieron a síndrome hipoplasia ventricular izquierdo y ventrículo único, cardiopatías de difícil tratamiento y elevada mortalidad. La sobrevida global alcanzó un 46,1 por ciento, cifra similar a estudios internacionales previamente reportados. La sobrevida fue mejor en pacientes con malformaciones cardíacas únicas, que en pacientes que presentaron malformaciones más severas. Conclusión: Es importante mejorar el diagnóstico de cardiopatías ductus dependientes aisladas para mejorar la sobrevida en estos grupos de pacientes.


Subject(s)
Female , Pregnancy , Humans , Heart Defects, Congenital/diagnosis , Heart Defects, Congenital/epidemiology , Prenatal Diagnosis , Chromosome Aberrations/statistics & numerical data , Heart Defects, Congenital/complications , Heart Defects, Congenital/genetics , Follow-Up Studies , Prognosis
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