Pirfenidone Reverts Global DNA Hypomethylation, Promoting DNMT1/UHRF/PCNA Coupling Complex in Experimental Hepatocarcinoma.

Hepatocellular carcinoma (HCC) development is associated with altered modifications in DNA methylation, changing transcriptional regulation. Emerging evidence indicates that DNA methyltransferase 1 (DNMT1) plays a key role in the carcinogenesis process. This study aimed to investigate how pirfenidone (PFD) modifies this pathway and the effect generated by the association between c-Myc expression and DNMT1 activation. Rats F344 were used for HCC development using 50 mg/kg of diethylnitrosamine (DEN) and 25 mg/kg of 2-Acetylaminofluorene (2-AAF). The HCC/PFD group received simultaneous doses of 300 mg/kg of PFD. All treatments lasted 12 weeks. On the other hand, HepG2 cells were used to evaluate the effects of PFD in restoring DNA methylation in the presence of the inhibitor 5-Aza. Histopathological, biochemical, immunohistochemical, and western blot analysis were carried out and our findings showed that PFD treatment reduced the amount and size of tumors along with decreased Glipican-3, ß-catenin, and c-Myc expression in nuclear fractions. Also, this treatment improved lipid metabolism by modulating PPARγ and SREBP1 signaling. Interestingly, PFD augmented DNMT1 and DNMT3a protein expression, which restores global methylation, both in our in vivo and in vitro models. In conclusion, our results suggest that PFD could slow down HCC development by controlling DNA methylation.

Influencia de la anastomosis de las arterias umbilicales (Hyrtl's) en la morfometría y eficiencia placentaria / Influence of the anastomosis of the umbilical arteries (Hyrtl's) on the morphometry and efficiency of the placenta

La anastomosis de Hyrtl's (AH), vaso único con amplia variabilidad anatómica, comunica las arterias umbilicales cerca de la inserción del cordón umbilical en las placentas humanas. El objetivo del presente trabajo fue determinar si existe relación entre las características morfométricas de la placenta y la presencia de anastomosis y analizar si esta tiene influencia en la eficiencia placentaria. Estudio descriptivo. Se analizaron 60 placentas provenientes de madres que aceptaron participar en la investigación, embarazo único, a término (entre 37,0 y 41,6 semanas), con edades entre 18 y 37 años, con al menos cuatro visitas a control prenatal, sin comorbilidades. Las características placentarias de peso, diámetros y grosor se tomaron en fresco. Una vez fijadas con formaldehido al 10 %, mediante disección se ubicó, clasificó y fotografió la anastomosis. El peso de la placenta fue 494,4 ± 87,1 gramos, el grosor central correspondió a 1,7 ± 0,4 cm, DM 19,9 ± 2,0 cm y Dm 18,4 ± 1,7 cm. La inserción de cordón predominante fue excéntrica (65 %) y la forma discoidea u ovalada (60 %). En 51 placentas se ubicó la presencia de anastomosis (85 %). En el grupo de placentas con presencia AH se encontró un peso placentario más bajo al compararlo con el grupo que no presentó AH, el resto de las características morfométricas de la placenta, incluido el tipo de inserción de cordón umbilical no presentaron relación con la anastomosis. La eficiencia placentaria expresada con la relación entre peso neonato/peso placenta presentó diferencias significativas en el grupo con presencia de anastomosis, con mayores valores comparados con el grupo sin anastomosis. La presencia de AH contribuye positivamente a la eficiencia placentaria. Sin embargo, el incremento del peso placentario puede ser un efecto compensador de la placenta y no siempre indica una mayor eficiencia funcional del órgano.

SUMMARY: Hyrtl's anastomosis (HA), a single vessel, with wide anatomical variability, communicates the umbilical arteries, near the insertion of the umbilical cord in human placentas. The objective of this study was to determine if there is a relationship between the morphometric characteristics of the placenta and the presence of the anastomosis and to analyze if this influences the placental efficiency. Descriptive study. We analyzed 60 placentas from mothers who agreed to participate in the study, single pregnancy, term (between 37.0 and 41.6 weeks), aged between 18 and 37 years with at least four visits to prenatal control, without comorbidities. The placental characteristics of weight, diameters and thickness were taken fresh. Once fixed with 10 % formaldehyde, the anastomosis was located, classified, and photographed by dissection. The weight of the placenta was 494.4 ± 87.1 g, the central thickness corresponded to 1.7 ± 0.4 cm, the MD 19.9 ± 2.0 cm and Dm 18.4 ± 1.7 cm: The predominant cord insertion was eccentric, with 65 % and the discoid or oval shape with 60 %. In 51 placentas the presence of anastomosis was found (85 %). In the group of placentas with AH presence, a lower placental weight was found when compared to the group that did not present AH, the rest of the morphometric characteristics of the placenta, including the type of umbilical cord insertion, were not related to the anastomosis. Placental efficiency expressed as the neonatal weight/placental weight ratio showed significant differences in the group with presence of anastomosis, with higher values compared to the group without anastomosis. The presence of HA contributes positively to placental efficiency. However, the increase in placental weight may be a compensatory effect of the placenta and does not always indicate a greater functional efficiency of the organ.

Anisakis and anisakidosis: hosts and case reports in South America. Systematic review / Anisákidos y anisakidosis: reportes de caso y hospedadores en América del Sur. Revisión sistemática

Abstract Introduction: Anisakidosis is a disease caused by the consumption of raw or undercooked seafood parasitized by nematode larvae of the family Anisakidae. Even though it is a public health issue in Europe and Asia, it is relatively unknown in South America. Objective: To present case reports on anisakidosis and the intermediate hosts of Anisakis reported in South America. Materials and methods: A systematic review was conducted in Medline, Cochrane, Embase, LILACS and Scopus using a structured search of MeSH and DeCS descriptors. The search strategy included publication period: inception of each database-September 2018; languages: English, Spanish, and Portuguese; and study types: case reports and observational cross-sectional studies. The review was complemented with an unstructured search in SciELO and Google Scholar. Results: The initial search yielded 172 articles. After removing duplicates and reviewing the inclusion criteria, 69 studies were selected for full analysis: 19 case reports and 50 host records. The most reported form of anisakidosis was gastrointestinal anisakidosis with 45 cases; this infectious disease was caused by a single larva in 41 people (91.1%). Reports of 95 species of fish for human consumption parasitized by larvae of the genera Anisakis, Contracaecum, Pseudoterranova and Hysterothylacium were identified in Argentina (22 fish species), Brazil (34 species), Chile (15 species), Colombia (17 species), Ecuador (8 species), Peru (7 species), Uruguay and Venezuela (2 species each). Conclusion: Anisakidosis is a latent risk in South America, so it is necessary to establish effective regulations for efficiently controlling the appearance of this parasitic disease in the region. Furthermore, the general population should receive more information about the precautions regarding saltwater fish consumption.

Resumen Introducción. La anisakidosis es una parasitosis ocasionada por el consumo de pescado de mar crudo o semicrudo parasitado por larvas de nematodos de la familia Anisakidae. En Europa y Asia es un problema de salud pública; sin embargo, en América del Sur es poco conocida. Objetivo. Identificar los reportes de caso de anisakidosis y los hospedadores intermediarios de anisákidos reportados en América del Sur. Materiales y métodos. Se realizó una revisión sistemática en Medline, Cochrane, Embase, LILACS y Scopus mediante la búsqueda estructurada de términos MeSH y DeCS. Estrategia de búsqueda: periodo de publicación: inicio de cada base de datos-septiembre de 2018; idiomas: inglés, español y portugués; tipos de estudio: reportes de caso y estudios transversales observacionales. La revisión fue complementada con una búsqueda no estructurada en SciELO y Google Scholar. Resultados. La búsqueda inicial arrojó 172 artículos. Una vez removidos los duplicados y revisados los criterios de inclusión, se seleccionaron 69 estudios para análisis completo: 19 reportes de caso y 50 registros de hospedadores. La forma de anisakidosis más reportada fue la gastrointestinal, con 45 casos, donde la parasitosis fue causada por una larva única en 41 casos (91.1%). Se identificaron reportes de 95 especies de peces para consumo humano parasitadas por los géneros Anisakis, Contracaecum, Pseudoterranova e Hysterothylacium en los siguientes países: Argentina (22 especies), Brasil (34 especies), Chile (15 especies), Colombia (17 especies), Ecuador (8 especies), Perú (7 especies), Venezuela (4 especies) y Uruguay (2 especies). Conclusión. La anisakidosis es un riesgo latente para América del Sur, por lo que es necesario instaurar normativas efectivas para controlar su aparición en la región y brindar más información a la población general sobre las precauciones necesarias en relación con el consumo de pescado de agua salada.

Tightening Bonds in Latin America Through Phage Discovery.

Between 2015 and 2019, we hosted an International Phage Course at Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina. The 2-week full-time course was hands-on and included lectures from renowned phage biologists. Participating students were able to meet and discuss with recognized experts from around the world in a familiar setting, facilitating the establishment of scientific collaborations and the expansion of their networks. Eighty-four students from 14 Latin American countries have participated in the course, which included isolation, characterization, genome sequencing, and annotation of novel phages. We have successfully created a coursework that enabled the acquisition of new knowledge and expertise in bacteriophage biology and strengthened ties among Latin American colleagues.

Isolation and Characterization of vB_MsmS_Celfi: A New Mycobacterium tuberculosis Bacteriophage.

Introduction: Because of the clinical relevance of Mycobacteria, and from a therapeutic perspective, there is an increasing interest to study phages that infect bacteria belonging to this genus. Materials and Methods: A phage was isolated from a soil sample, using Mycobacterium smegmatis as host. Its characterization included sequencing, annotation, and analysis of the genome, host range determination, and electron microscopy imaging. Results: Mycobacterium phage vB_MsmS_Celfi is a temperate phage able to infect Mycobacterium tuberculosis with high efficiency. From electron microscopy images, Celfi belongs to the Siphoviridae family. Genome analysis classified phage Celfi into cluster L, subcluster L2 of Actinobacteriophage clusters. Mycobacterium phage Celfi exhibits a Lysin B distant to those present in other members of the subcluster and other mycobacteriophages. Conclusions: The discovery of new phages that infect M. tuberculosis could contribute to the development of novel tools for detection systems and future treatment of the disease.

Genome Sequence and Characterization of Lactobacillus casei Phage, vB_LcaM_Lbab1 Isolated from Raw Milk.

Introduction: Only a few Lactobacillus casei phages have so far been characterized. As several L. casei strains are part of probiotic formulations, bacteriophage outbreaks targeting these strains can lead to critical losses within the dairy industry. Materials and Methods: A new L. casei phage was isolated from raw milk obtained from a milking yard from the province of Buenos Aires. The phage genome was sequenced, annotated, and analyzed. Morphology was determined by electron microscopy and the host range was established. Results: Lactobacillus phage vB_LcaM_Lbab1 is a member of the Herelleviridae family and features a host range including L. casei/Lactobacillus paracasei and Lactobacillus kefiri strains. We further analyzed the baseplate proteins in silico and found putative carbohydrate binding modules that are responsible for host recognition in other Lactobacillus phages. Conclusions: A new Lactobacillus phage was isolated and characterized. The focus was made on its host recognition mechanism, pointing toward the development of future strategies to avoid deleterious infections in the dairy industry.

Structural remodelling of the heart valves extracellular matrix during embryo development.

Alterations in heart valve development represent more than 20% of congenital cardiovascular malformations. Most of the functional properties of heart valves depend on extracellular matrix. Despite its relevance, little is known about fibrillar components on developing stages. Our objective is to define histological changes on valves fibrillar components in late embryonic development of Mus musculus. We found type III collagen as the predominant fibre type in the ECM in prenatal stages followed by a switch to a type I predominance for postnatal ages. The change in fibrillar components is necessary to support the normal mechanical function of adult heart valves.

Anisákidos y anisakidosis: generalidades y su actualidad en Colombia. Revisión bibliográfica / Anisakis and Anisakiasis: General aspects and current situation in Colombia

RESUMEN La anisakidosis es una parasitosis ocasionada por nematodos de la familia Anisakidae, causa-da por el consumo de pescado parasitado con larvas infectivas (L3) de estos nematodos. En Europa y Asia es un problema de salud pública. Sin embargo, en Colombia y en general en los países de América del Sur, es poco conocida. El objetivo de este trabajo es presentar una revisión de las generalidades de los parásitos anisákidos y mostrar la situación actual de esta parasitosis en Colombia. Se realizó una búsqueda estructurada de términos MeSH y DeCS en MEDLINE, Cochrane, Embase, LILACS y Scopus; esta se complementó con otra no estructurada en SciELO y Google Scholar. Se incluye un reporte de caso y seis registros de hospederos. Se describen registros de peces de consumo humano parasitados por Anisakis sp., Anisakis physeteris y Pseudoterranova decipiens para el Océano Pacífico y, los géneros Pseudoterranova y Contracaecum en peces del Océano Atlántico y aguas continentales. Se concluye que la anisakidosis representa un riesgo latente para Colombia, es necesario instaurar legislaciones efectivas para un control eficiente sobre esta parasitosis y educar a la población sobre los cui-dados necesarios para el consumo de pescado.

SUMMARY Anisakidosis is a parasitic disease derived from the consumption of infective larvae from Anisakidae family. In Europe and Asia is a public health problem, however, in Colombia and South American countries is little known. The objective is to review Anikids general aspects and find out about the current situation of this disease in Colombia. Search of MeSH and DeCS terms, through MEDLINE, Cochrane, Embase, and Scopus databases, complemented with grey literature from SciELO and Google Scholar, was made. One case report and six host records were included. Records of fish for human consumption from Pacific Ocean parasitized by Anisakis sp., Anisakis physeteris and Pseudoterranova decipiens are described, as well as for fish from Atlantic Ocean and inland waters with genera Pseudoterranova and Contracaecum. Anisakidosis represents a latent risk for Colombia; it is necessary to establish effective legislations for an efficient control of the emergence of this parasitic disease, as well as to educate people about needed precautions considering fish consumption.

First reporting of Anisakis sp. in the Armed Snook fish (Centropomus armatus) caught and commercialized in Buenaventura, Colombia / Primer reporte de Anisakis sp. en el pez Róbalo (Centropomus armatus) capturado y comercializado en Buenaventura, Colombia

Objective: Nematodes of the Anisakidae family are parasites found in aquatic organisms. The lack of studies on anisakidosis and Anisakis in Colombia has meant this type of parasitosis is not widely known by health personnel and underreporting of the disease is highly likely. The objective of this study was to identify anisakid nematodes in the armed snook fish (Centropomus armatus) obtained by artisanal fishing and sold commercially in the coastal port city of Buenaventura. Material and methods: Morphological identification of these worms was performed using taxonomic keys and supplemented with microscopic study using the histochemical Hematoxylin-Eosin technique. Results: Nematodes of the genus Anisakis were found in 42% and the mean abundance was 2.8 in the C. armatus. Conclusions: The findings confirm the presence of Anisakis sp. in fish for human consumption in Buenaventura, the main fishing port in the Colombian Pacific region. This finding in itself warrants further investigation into the possibility of an emerging disease in Colombia.

Objetivos: Los nematodos de la familia Anisakidae son parásitos de organismos acuáticos. La falta de estudios en anisakidosis y anisakidos en Colombia ha resultado en el desconocimiento de esta infección por parte del personal de salud y un posible subregistro de la enfermedad. El objetivo de este estudio fue identificar nematodos anisakidos en el pez róbalo (Centropomus armatus), obtenido por pesca artesanal y comercializado en la localidad de Buenaventura. Materiales y métodos: La identificación morfológica se realizó usando claves taxonómicas para estos gusanos complementada con estudio microscópico mediante técnica histoquímica de Hematoxilina-Eosina. Resultados: Se encontraron nemátodos del género Anisakis en 42% y una abundancia promedio de 2.8 en el hospedero C. armatus. Conclusiones: Los hallazgos confirman la presencia de Anisakis sp. en peces de consumo humano de Buenaventura, principal puerto pesquero en la región Pacífica colombiana, lo cual abre el camino en la investigación de una posible enfermedad emergente en este país.

[Blood-feeding of Rhodnius prolixus].

Triatomines (Hemiptera: Reduviidae) are blood-sucking insect vectors of the protozoan Trypanosoma cruzi which is the causative agent of Chagas' disease. Rhodnius prolixus is the most epidemiologically important vector of T. cruzi in Colombia. Triatomines are regarded to be vessel-feeders as they obtain their blood meals from vertebrate hosts by directly inserting their mouthparts into vessels. Microscopic techniques are useful for visualizing and describing the morphology of biological structures. Here, we show images of the blood-feeding of R. prolixus, including some histological features by light microscopy and scanning electron microscopy of the mouthparts of R. prolixus when feeding on a laboratory mouse.

A histological ontology of the human cardiovascular system.

BACKGROUND: In this paper, we describe a histological ontology of the human cardiovascular system developed in collaboration among histology experts and computer scientists. RESULTS: The histological ontology is developed following an existing methodology using Conceptual Models (CMs) and validated using OOPS!, expert evaluation with CMs, and how accurately the ontology can answer the Competency Questions (CQ). It is publicly available at http://bioportal.bioontology.org/ontologies/HO and https://w3id.org/def/System . CONCLUSIONS: The histological ontology is developed to support complex tasks, such as supporting teaching activities, medical practices, and bio-medical research or having natural language interactions.

Anisakidae nematodes isolated from the flathead grey mullet fish (Mugil cephalus) of Buenaventura, Colombia.

Anisakiasis is a parasitic infection caused by larval stages of nematodes of the genus Anisakis, Pseudoterranova and Contracaecum, of the Anisakidae family. The lifecycle of these nematodes develops in aquatic organisms and their final hosts are marine mammals. However, humans can act as accidental hosts and become infected with infective stage larvae (L3) by consuming raw or undercooked fish or shellfish carrying the parasite. Of this group of parasites, the genus Anisakis is the most studied: its presence in humans is associated with non-specific gastrointestinal symptoms or allergic responses that can trigger anaphylactic shock. The lack of studies in anisakiasis and Anisakis in Colombia has resulted in this infection being little-known by medical practitioners and therefore potentially underreported. The objective of this study was to identify anisakid nematodes in the flathead grey mullet fish (Mugil cephalus), caught by artisanal fishing methods and commercialized in Buenaventura. Morphological identification was carried out by classical taxonomy complemented by microscopy study using the histochemical technique Hematoxylin-Eosin. Nematodes of the genus Anisakis were found in the host M. cephalus. The Prevalence of Anisakis larvae in flathead grey mullet fish was 33%. The findings confirm the presence of Anisakis sp. in fish for human consumption in the Colombian Pacific region, a justification for further investigation into a possible emerging disease in this country.

Blood-feeding of Rhodnius prolixus

Triatomines (Hemiptera: Reduviidae) are blood-sucking insect vectors of the protozoan Trypanosoma cruzi which is the causative agent of Chagas' disease. Rhodnius prolixus is the most epidemiologically important vector of T. cruzi in Colombia. Triatomines are regarded to be vessel-feeders as they obtain their blood meals from vertebrate hosts by directly inserting their mouthparts into vessels. Microscopic techniques are useful for visualizing and describing the morphology of biological structures. Here, we show images of the blood-feeding of R. prolixus, including some histological features by light microscopy and scanning electron microscopy of the mouthparts of R. prolixus when feeding on a laboratory mouse.

Los triatominos (Hemiptera: Reduviidae) son insectos hematófagos vectores del protozooTrypanosoma cruzi, el cual causa la enfermedad de Chagas. Rhodnius prolixus es el vector de T. cruzi de mayor importancia epidemiológica en Colombia. Para alimentarse, los triatominos introducen su probóscide directamente en los vasos sanguíneos de los huéspedes vertebrados. La microscopía es una técnica útil para visualizar y describir la morfología de estructuras biológicas. Se presentan imágenes de la hematofagia de R. prolixus, incluidas algunas características histológicas visibles por microscopía de luz y microscopía electrónica de barrido de las partes bucales de R. prolixus al alimentarse de un ratón de laboratorio.

Diagnóstico etiológico en meningitis y encefalitis por técnicas de biología molecular / Etiologic diagnosis in meningitis and encephalitis molecular biology techniques

Introducción: El estudio etiológico de las infecciones del sistema nervioso central se ha realizado tradicionalmente con cultivos bacterianos y con reacción en cadena de la polimerasa (PCR) para virus herpes simple (VHS). Los cultivos bacterianos pueden disminuir su rendimiento en pacientes que hayan usado antibióticos previos a la toma de muestra, y el solicitar PCR solo para virus VHS reduce el diagnóstico etiológico a un solo agente. El objetivo de este trabajo fue determinar las causas infecciosas en meningitis y encefalitis en niños, utilizando conjuntamente la microbiología convencional y la biología molecular, con el fin de mejorar el diagnóstico etiológico de estas enfermedades. Pacientes y método: Se estudiaron 19 pacientes con sospecha de meningitis y encefalitis, de manera prospectiva, hospitalizados en el hospital Luis Calvo Mackenna en Santiago de Chile, entre el 1 de marzo de 2011 y el 30 de marzo de 2012. Luego de obtener el consentimiento informado, a las muestras de LCR se les realizó examen citoquímico, cultivo, PCR múltiple bacteriana (N. meningitidis, S. pneumoniae, H. influenzae) y PCR en tiempo real para HSV-1 y 2, VVZ, VEB, CMV, VHH-6 y enterovirus. Se recabaron datos clínicos y epidemiológicos desde la ficha clínica del paciente. Resultados: De los 19 pacientes analizados 2 (10%) fueron diagnosticados por métodos microbiológicos convencionales y 7 (37%) al adicionar biología molecular (p = 0,02). Tres pacientes presentaron meningitis por S. pneumoniae, uno por Enterobacter cloacae, 2 pacientes meningoencefalitis por VHS-1 y uno meningitis por VVZ. Conclusiones: La adición de la PCR a los métodos microbiológicos convencionales de diagnóstico en las infecciones del sistema nervioso central aumenta significativamente la probabilidad de detectar el agente causal. La incorporación rutinaria del diagnóstico molecular permitiría un manejo más oportuno y racional.

Introduction: The aetiological study of infections of the central nervous system has traditionally been performed using bacterial cultures and, more recently, using polymerase chain reaction (PCR) for herpes simplex virus (HSV). Bacterial cultures may not have good performance, especially in the context of patients who have received antibiotics prior to sampling, and a request for HSV only by PCR reduces the information to only one aetiological agent. The aim of this study is to determine the infectious causes of meningitis and encephalitis, using traditional microbiology and molecular biology to improve the aetiological diagnosis of these diseases. Patients and method: A prospective study was conducted on 19 patients with suspected meningitis, admitted to the Luis Calvo Mackenna Hospital in Santiago, Chile, from March 1, 2011 to March 30, 2012. After obtaining informed consent, the CSF samples underwent cytochemical study, conventional culture, multiplex PCR for the major producing bacterial meningitis (N. meningitidis, S. pneumoniae, H. influenzae), real-time single PCR for HSV-1 and 2, VZV, EBV, CMV, HHV-6 and enterovirus. Clinical and epidemiological data were also collected from the clinical records. Results: Of the 19 patients analysed, 2 were diagnosed by conventional methods and 7 by adding molecular biology (increase to 37%). Three patients had meningitis due to S. pneumoniae, one due to Enterobacter cloacae, 2 patients meningoencephalitis HSV-1, and one VZV meningitis. Conclusions: The addition of PCR to conventional diagnostic methods in CNS infections increases the probability of finding the causal agent. This allows a more adequate, timely and rational management of the disease.

[Etiologic diagnosis in meningitis and encephalitis molecular biology techniques]. / Diagnóstico etiológico en meningitis y encefalitis por técnicas de biología molecular.

INTRODUCTION: The aetiological study of infections of the central nervous system has traditionally been performed using bacterial cultures and, more recently, using polymerase chain reaction (PCR) for herpes simplex virus (HSV). Bacterial cultures may not have good performance, especially in the context of patients who have received antibiotics prior to sampling, and a request for HSV only by PCR reduces the information to only one aetiological agent. The aim of this study is to determine the infectious causes of meningitis and encephalitis, using traditional microbiology and molecular biology to improve the aetiological diagnosis of these diseases. PATIENTS AND METHOD: A prospective study was conducted on 19 patients with suspected meningitis, admitted to the Luis Calvo Mackenna Hospital in Santiago, Chile, from March 1, 2011 to March 30, 2012. After obtaining informed consent, the CSF samples underwent cytochemical study, conventional culture, multiplex PCR for the major producing bacterial meningitis (N. meningitidis, S. pneumoniae, H. influenzae), real-time single PCR for HSV-1 and 2, VZV, EBV, CMV, HHV-6 and enterovirus. Clinical and epidemiological data were also collected from the clinical records. RESULTS: Of the 19 patients analysed, 2 were diagnosed by conventional methods and 7 by adding molecular biology (increase to 37%). Three patients had meningitis due to S. pneumoniae, one due to Enterobacter cloacae, 2 patients meningoencephalitis HSV-1, and one VZV meningitis. CONCLUSIONS: The addition of PCR to conventional diagnostic methods in CNS infections increases the probability of finding the causal agent. This allows a more adequate, timely and rational management of the disease.

Músculo esquelético y lesión por reperfusión. ultraestructura, alteración y regeneración: revisión sistemática / Skeletal muscle and reperfusion injury: ultrastructure, disease and regeneration: systematic review

Introducción: La función tisular se basa en la asociación celular y la comunicación mediante uniones intercelulares o la matriz extracelular, que compone el tejido conectivo. La isquemia conlleva a cambios de lesión a los cuales las células responden según duración e intensidad del estímulo de lesión. En periodos cortos de isquemia y prolongados de reperfusión, el tejido muscular estriado esquelético presenta cambios en la predominancia de los tipos de fibras musculares y en los componentes de la matriz extracelular intramuscular. Objetivo: Establecer los cambios que se presentan en el músculo esquelético durante la reperfusión prolongada, tanto en las fibras musculares como en su matriz extracelular. Métodos: Se realizó una revisión sistemática mediante la búsqueda de artículos en inglés y español publicados en revistas indexadas en las bases de datos Ovid Medline, PubMed, Wiley y Science Direct. Los descriptores MESH utilizados fueron skeletal muscle, ischemia, reperfusion, fiber type fast twitch, fiber type slow twitch, sarcomere and myoblast. Se acoplaron los términos histology y tissue. Resultados: Se seleccionaron 81 publicaciones y se complementó con imágenes de músculos esqueléticos provenientes de muestras procesadas en el Laboratorio de Histología de la Universidad del Valle, Colombia. Conclusión: La recuperación del músculo durante la reperfusión seguida de isquemia, tiende hacia el patrón histológico y funcional normal. En algunos casos es un proceso lento y que aún después de varios meses no ha finalizado. Así mismo, pueden persistir alteraciones leves o moderadas en la contracción muscular, dados los cambios que se presentan en la matriz extracelular intramuscular.

Introduction: The tissue function is based on the cell association andcommunication through junctions or the extracellular matrix, which comprisesconnective tissue. Ischemia injury leads to changes to which the cells respondand it depends on duration and intensity of stimulus injury. In short periodsof prolonged ischemia and reperfusion, skeletal striated muscle tissue showschanges in the predominance of muscle fiber types and components of theextracellular matrix intramuscular. Objective: To determine the changes whichoccur in skeletal muscle during prolonged reperfusion in both muscle fibersin its extracellular matrix. Methods: A systematic review was performed bysearching for articles in English and Spanish published in journals indexed indatabases Ovid Medline, PubMed, Science Direct and Wiley. MeSH descriptorsused were skeletal muscle, ischemia, reperfusion, fast twitch fiber type, slowtwitch fiber type, sarcomere and myoblast. The terms tissue and histology werecoupled. Results: 81 relevant publications were selected and supplementedwith images of skeletal muscles from samples processed at the Laboratory ofHistology of the Universidad del Valle, Colombia. Conclusion: The recoveryof muscle during ischemia followed by reperfusion, tends toward the normalhistological and functional pattern. In some cases it is a slow process and evenafter several months has not been completed. Likewise, they may persist mildor moderate alterations in muscle contraction, given the changes that occur inthe intramuscular extracellular matrix.

Actividad antimicrobiana y sinérgica de metabolitos producidos por Streptomyces erythrogriseus M10-77 de origen marino / Antimicrobial and synergetic activity of metabolites produced by marine origin Streptomyces erythrogriseus M10-77

Los metabolitos de un actinomiceto de origen marino, identificado como Streptomyces erythrogriseus cepa M10-77, fueron evaluados por su capacidad antimicrobiana y sinérgica con antibióticos convencionales. Las pruebas de antagonismo se realizaron frente a patógenos multidrogorresistentes (MDR) de origen clínico, siendo muy efectivos principalmente frente a especies patógenas de Staphylococcus y Enterococcus. Se determinó la Concentración Mínima Inhibitoria (CMI) de extractos diclorometánicos frente a los patógenos S. aureus 1094, S. epidermidis 1093 y Staphylococcus coagulasa negativo 348, siendo estos valores de 3,9; 15,7 y 1,9 µg/mL respectivamente. Los componentes del extracto diclorometánico fueron fraccionados parcialmente, obteniéndose hasta 4 fracciones orgánicas (I, II, III, IV), las que mostraron actividades inhibitorias de la cepa referencial S. aureus ATCC 43300. Los bioensayos frente a S. aureus meticilino resistente (MRSA) mostraron actividad sinérgica de la fracción II del extracto con antibióticos betalactámicos y aminoglucósidos, resaltando la repotenciación de la actividad de la bencilpenicilina en 128 veces el valor basal; así como de la gentamicina en 8 veces sobre el valor basal. S. erythrogriseus cepa M10-77 resultó ser un productor de metabolitos antibacterianos de alta potencia y con actividad sinérgica con antibióticos de referencia médica.

Metabolites of a marine actinomycete, identified as Streptomyces erythrogriseus M10-77 strain were evaluated for antimicrobial and synergistic activity with conventional antibiotics. Antagonism tests were conducted against multidrug resistant (MDR) pathogens of clinical origin, being very effective mainly against pathogenic Staphylococcus and Enterococcus. Minimum Inhibitory Concentrations (MIC) of dichloromethane extracts were determined against pathogenic S. aureus 1094, S. epidermidis and coagulase-negative Staphylococcus 1093 348, these values being 3.9; 15.7 and 1.9 μg/mL respectively. The components of dichloromethane extracts were fractionated partially yielding four organic fractions (I, II, III, IV), which showed inhibitory activity against the reference strain S. aureus ATCC 43300. The bioassays against S.aureus methicillin-resistant (MRSA ) produced synergistic activity of the extract fraction II with beta-lactams and aminoglycoside antibiotics, highlighting the upgrading of the activity of penicillin at 128 times above the baseline and gentamicin 8-fold above baseline. S. erythrogriseus M10-77 strain proved to be a producer of antibacterial metabolites with high power and synergistic activity with antibiotics of medical use.

Determinación de la fosfatasa ácida tartrato resistente en muestras óseas decalcificadas de cerdo Sus domesticus / Determining tartrate-resistant acid phosphatase in decalcified bone samples pig Sus domesticus

Introducción: Las técnicas de Inmuno - histoquímica son hoy en día una de las herramientas más importantes en el diag- nostico histopatológico, sin embargo la manipulación de las muestras y el método de procesamiento puede llevar a cambios en la estructura de las proteínas que llevan a enmascaramiento de antígenos, dificultan - do la identificación con anticuerpos. Entre los diferentes métodos de recuperación an- tigénico propuestos en la literatura, el de calor húmedo con Vaporera ha tenido gran aceptación por su simplicidad, control y bajo costo. Objetivo: En el presente trabajo se propone un protocolo de recuperación antigénica con calor húmedo, en muestras de tejido óseo que ya habían sido previamente fijadas en formaldehido, decalcificadas con etilen - diaminotetraacético (EDTA), e incluidas en parafina. Materiales y método: Se utilizaron mues- tras de tejido óseo de cerdo que habían sido preparadas con técnicas convencionales, pertenecientes a la colección del laboratorio de patología de la Universidad del Valle. Se realizó refijacion en glutaraldehido y se empleó una vaporera para intensificar la exposición de antígenos. Se utilizó como anticuerpo primario el anti TRAP de DEKO®, monoclonal, originado en ratón, y como secundario el KIT UltraVision LP Large Volume Detection System HRP Polymer ®. Resultados: En todas las muestras expues- tas al anticuerpo primario en diluciones 1:20 y 1:40 se observó inmunotinción de células mononucleares compatibles con pre osteoclastos, y células gigantes mul - tinucleadas compatibles con osteoclastos. Conclusiones: La recuperación antigénica con calor húmedo es un método confiable en la recuperación antigénica de muestras óseas fijadas con formaldehido...(Au)

ntroduction: Nowadays, Immunohisto - chemistry are one of the most important techniques in the histopathological diagno - sis. Despite of handling and processing cau - tions, both of them may generate changes in the protein structure, masking antigens, preventing antibody identification. Among different antigen retrieval methods propo- sed by the literature, the humid heat with Steamer has been widely accepted for its simplicity, control and low cost. Objective: In this paper a protocol for humid heat antigen retrieval use in bone tissue samples that had been previously fixed in formaldehyde, decalcified with ethylenediaminetetraacetic (EDTA ), and embedded in paraffin is proposed. Materials and methods: Samples of pig's bone that had been prepared with conven- tional techniques, from the collection of the pathology laboratory of the University of Valle were used. New fixed process was performed in glutaraldehyde and a steamer was used to enhance antigen exposure. The anti-TRAP DEKOs ®, mouse monoclonal antibody was used as primary antibody, and the KIT UltraVision LP Large Volume Detection System HRP Polymer ® was used as a secondary antibody. Results: In all samples exposed to primary antibody in 1:20 and 1:40 dilutions immu - nostaining mononuclear cells compatible with preosteoclasts were observed; im - munostaining multinucleated giant cells consistent with osteoclasts were described. Conclusions: Humid heat for antigenic recovery is a reliable method for the reco- very of bone antigen samples fixed with formaldehyde...(Au)

Establecimiento de un protocolo de reproducción para la obtención de especímenes murinos embrionarios/fetales / Establishment of a Breeding Protocol for Obtaining Embryonic/Fetal Murine Specimens / Estabelecimento de um protocolo de reprodução para a obtenção de espécimes murinas embrionárias/fetais

La investigación científica utiliza modelos animales en situaciones experimentales en las que es controversial investigar con especímenes humanos; tal es el caso de la investigación con muestras embrionarias/fetales, donde se requieren estrictos protocolos reproductivos que posibiliten un cálculo preciso de la edad gestacional y con ello la obtención de muestras adecuadas. El ratón es el modelo de experimentación más utilizado, pues es de fácil manipulación y eficiencia reproductiva. El objetivo de este trabajo es presentar un protocolo de reproducción que permite determinar con certeza el día de preñez en biomodelo Mus musculus, para la obtención de especímenes embrionarios/fetales.

Scientific research uses animal models in experimental situations where it is controversial to research with human specimens; such is the case of research with embryonic/fetal samples, where strict reproductive protocols are required that enable the accurate calculation of gestational age and thus obtaining appropriate sampling. Mice are the most widely used experimental models, as they are easy to handle and are of reproductive efficiency. The purpose of this paper is to present a reproduction protocol that makes it possible to determine the day of pregnancy in Mus musculus biomodel with certainty, in order to obtain embryonic/fetal specimens.

A pesquisa científica utiliza modelos animais em situações experimentais onde é controverso pesquisar com espécimes humanos, tal é o caso da pesquisa com amostras embrionárias/ fetais, donde se requer de estritos protocolos reprodutivos que possibilitem um cálculo preciso da idade gestational e com isso a obtenção de amostras adequadas. O rato é o modelo de experimentação mais utilizado, pois é de fácil manipulação e eficiência reprodutiva. O objetivo deste trabalho é apresentar um protocolo de reprodução que permite determinar com certeza o dia de prenhez em biomodelo Mus musculus, para a obtenção de espécimes embrionários/fetais.