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Nest architecture plays a fundamental role in the adaptation of ants to their habitat, favoring the action of economically important species. Ectatomma ruidum sp. 2 (ruidum species complex) is a biological control agent in Neotropical agroecosystems, exhibiting high bioturbation impact due to high nest densities. The architecture and composition of 152 nests were studied in two Andean populations of southwestern Colombia, 24 of them being cast using the paraffin wax technique. Nest entrance was a single, circular, 4 mm hole at ground level, without any special external structure, connected to a single vertical tunnel communicating with successive half ellipsoidal chambers. Nests were extremely shallow (depth range: 28.7-35.4 cm), with an average of six chambers and an overall volume of 92.2 cm3 per nest. The deeper the chamber, the smaller its volume. Nest building was independent of plants or roots, and no surface or underground physical connections were found between neighboring nests. Few nests possessed a queen, and neither ergatoids nor microgynes were recorded. Despite significant interactions between localities and the number of both males and workers, queen presence had an overall highly positive effect on the number of workers and larvae and a negative one on the number of gynes. Overall, the studied Colombian populations of E. ruidum sp. 2 retained the simple nest structure described for other species of this species complex and for colonies of the same species from other geographical areas, though they constrasted in their extreme shallowness. Our data suggest that E. ruidum sp. 2, at the local level, does not follow the usual monodomic pattern of this species with facultative polygyny but, rather, has a polydomic pattern with monogyny, perhaps related to the extreme shallowness of the nests due to soil structure, which could significantly enhance the queen's reproductive inhibition previously reported for this species.
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Formigas/fisiologia , Ecossistema , Comportamento de Nidação/fisiologia , Reprodução , Animais , Formigas/classificação , ColômbiaRESUMO
Objectives The quantitation of BCR-ABL1 mRNA is mandatory for chronic myeloid leukemia (CML) patients, and RT-qPCR is the most extensively used method in testing laboratories worldwide. Nevertheless, substantial variation in RT-qPCR results makes inter-laboratory comparability hard. To facilitate inter-laboratory comparative assessment, an international scale (IS) for BCR-ABL1 was proposed. Methods The laboratory-specific conversion factor (CF) to the IS can be derived from the World Health Organization (WHO) genetic reference panel; however, this material is limited to the manufacturers to produce and calibrate secondary reference reagents. Therefore, we developed secondary reference calibrators, as lyophilized cellular material, aligned to the IS. Our purpose was both to re-evaluate the CF in 18 previously harmonized laboratories and to propagate the IS to new laboratories. Results Our field trial including 30 laboratories across Latin America showed that, after correction of raw BCR-ABL1/ABL1 ratios using CF, the relative mean bias was significantly reduced. We also performed a follow-up of participating laboratories by annually revalidating the process; our results support the need for continuous revalidation of CFs. All participating laboratories also received a calibrator to determine the limit of quantification (LOQ); 90% of them could reproducibly detect BCR-ABL1, indicating that these laboratories can report a consistent deep molecular response. In addition, aiming to investigate the variability of BCR-ABL1 measurements across different RNA inputs, we calculated PCR efficiency for each individual assay by using different amounts of RNA. Conclusions In conclusion, for the first time in Latin America, we have successfully organized a harmonization platform for BCR-ABL1 measurement that could be of immediate clinical benefit for monitoring the molecular response of patients in low-resource regions.
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Proteínas de Fusão bcr-abl/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Calibragem , Humanos , América Latina , Controle de Qualidade , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
Ant parasitoidism has been reported in seven of the 26 recognized species of the mite genus Macrodinychus (Machrodynichidae). Macrodynichus sellnicki, previously reported as a parasitoid of the invasive ant Nylanderia fulva in Colombia, is now reported, in the same region, as attacking a native host, Ectatomma sp. 2 (E. ruidum complex). The mite develops within the protective silk cocoon of an Ectatomma pupa and waits for the emergence of the young ant before leaving the cocoon, unmolested. Overall nest prevalence was relatively high (34.6% of the 52 nests containing cocoons) but pupae prevalence was low (4.0%, n = 1401 cocoons). Mite life-history (parasite or parasitoid) was context dependent, shifting according to the intensity of the attack on a same host. Contrary to the strictly parasitoidic association of M. sellnicki with N. fulva, single mite attacks against E. ruidum did not result in host killing and solitary M. sellnicki (78.6% of the cases) behaved as parasites. However, in 21.4% of the attacks (0.9% of all available host pupae) more than one mite was involved and behaved as parasitoids, draining the host of its internal fluids and killing it. This is the first association of a macrodinychid mite with a species of the subfamily Ectatomminae, and the first ant associated mite for which such a context dependent life-style shift is described.
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Formigas/parasitologia , Interações Hospedeiro-Parasita , Estágios do Ciclo de Vida , Ácaros/crescimento & desenvolvimento , Animais , Colômbia , Feminino , Masculino , Parasitos/fisiologiaRESUMO
Gas gangrene, or clostridial myonecrosis, is usually caused by Clostridium perfringens and may occur spontaneously in association with diabetes mellitus, peripheral vascular disease, or some malignancies but more often after contamination of a deep surgical or traumatic lesion. If not controlled, clostridial myonecrosis results in multiorgan failure, shock, and death, but very little is known about the muscle regeneration process that follows myonecrosis when the infection is controlled. In this study, we characterized the muscle regeneration process after myonecrosis caused in a murine experimental infection with a sublethal inoculum of C. perfringens vegetative cells. The results show that myonecrosis occurs concomitantly with significant vascular injury, which limits the migration of inflammatory cells. A significant increase in cytokines that promote inflammation explains the presence of an inflammatory infiltrate; however, impaired interferon gamma (IFN-γ) expression, a reduced number of M1 macrophages, deficient phagocytic activity, and a prolongation of the permanence of inflammatory cells lead to deficient muscle regeneration. The expression of transforming growth factor ß1 (TGF-ß1) agrees with the consequent accumulation of collagen in the muscle, i.e., fibrosis observed 30 days after infection. These results provide new information on the pathogenesis of gas gangrene caused by C. perfringens, shed light on the basis of the deficient muscle regenerative activity, and may open new perspectives for the development of novel therapies for patients suffering from this disease.
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Clostridium perfringens/patogenicidade , Gangrena Gasosa/fisiopatologia , Músculo Esquelético/fisiologia , Regeneração , Animais , Citocinas/metabolismo , Fibrose , Gangrena Gasosa/etiologia , Gangrena Gasosa/imunologia , Camundongos , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Necrose , Infiltração de NeutrófilosRESUMO
Ligia isopods exhibit a constrained morphology that makes identification difficult. In the Greater Caribbean, a convoluted taxonomic history has left the distributional limits of Ligia baudiniana unclear. To date, no confirmed records of this species exist from the American Gulf of Mexico. Herein, we report the presence of L. baudiniana in Sarasota-Manatee Florida, as confirmed by morphological and molecular approaches. This is the first record of this species in the region and a ~300Km extension of its range. Specimens were collected in mangroves, underscoring the importance of protecting these habitats.
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Objetivo: Describir la evolución de retinopatía de la prematuridad (ROP) en recién nacidos con bajo peso al nacer egresados del Servicio de Neonatología del Hospital Regional Docente de las Mercedes durante los años 2012-2013. Materiales y Métodos: Estudio descriptivo, transversal y retrospectivo que se incluyeron 118 recién nacidos pretérmino (RNPT) e excluyó a 25 sobrevivientes por ser referidos a otras instituciones, padecer de malformaciones congénitas o tener su ficha clínica incompleta. Se registró su evolución con respecto de la ocurrencia de ROP en los siguientes seis controles posterior a su nacimiento. Resultados: De los 118 RN con bajo peso al nacer, al final del período de estudio el 50.8% (60) evolucionaron en hacia la regresión espontánea con diagnóstico previo de ROP y en 16,9% (20) a estadios que necesitaron tratamiento con laserterapia, el restante 32,2% (38) tuvo buenos resultados con fondo de ojo normal (retina madura) previo a un diagnóstico de retina inmadura. Se encontró diferencia significativa en el promedio del peso al nacer (pË0,001, análisis de varianza) en los tres grupos estudiados. No se evidenció diferencias significativas entre la evolución de los RN por sexo. Conclusiones: Se encontró una frecuencia de 42% de ROP en los RNPT evaluados. Una asociación entre peso del RN y la necesidad de requerir laserterapia. En los RN de sexo masculino aprox. el 55% se ven curados durante el tercer control mientras que el sexo femenino lo hicieron en un 45 %.
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Background. Activating mutations in the RET gene leads to medullary thyroid carcinoma (MTC). Guidelines encourage performing RET analysis in subjects with hereditary and sporadic disease. Materials and Methods. Design. Observational, case series report study. Patients. Subjects diagnosed with MTC, with a thyroidectomy performed in a single center in Costa Rica between the years 2006 and 2015. Diagnosis and Follow-Up. Pre- and postoperative calcitonin, RET mutation, and neck ultrasound and tomography were obtained. Results. 21 subjects with histological diagnosis of MTC were followed up. The average age at diagnosis was 52.0 ± 15.7 years. The preoperative mean value of calcitonin was 1340 ± 665 pg/mL. Evidence of RET mutation was found in 26.3% of the patients, with only 2 of them grouped in the same kindred. We found statistically significant differences in mean ages between mutated (38.4 ± 20.2 y) versus nonmutated RET gene (54.6 ± 11.8 y, p = 0.04). There were no significant differences regarding tumor size, metastases, and surgical reintervention. Conclusions. We report the results of RET mutation analysis in subjects with MTC in a single center of Costa Rica. The availability of this tool increases the probability of identifying familial MTC, with the benefit of detecting affected subjects and their relatives at an earlier age.
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The phylogenetic position of the critically endangered Saint Croix ground lizard Ameiva polops is presently unknown and several hypotheses have been proposed. We investigated the phylogenetic position of this species using molecular phylogenetic methods. We obtained sequences of DNA fragments of the mitochondrial ribosomal genes 12S rDNA and 16S rDNA for this species. We aligned these sequences with published sequences of other Ameiva species, which include most of the Ameiva species from the West Indies, three Ameiva species from Central America and South America, and one from the teiid lizard Tupinambis teguixin, which was used as outgroup. We conducted Maximum Likelihood and Bayesian phylogenetic analyses. The phylogenetic reconstructions among the different methods were very similar, supporting the monophyly of West Indian Ameiva and showing within this lineage, a basal polytomy of four clades that are separated geographically. Ameiva polops grouped in a cluster that included the other two Ameiva species found in the Puerto Rican Bank: A. wetmorei and A. exsul. A sister relationship between A. polops and A. wetmorei is suggested by our analyses. We compare our results with a previous study on molecular systematics of West Indian Ameiva.
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Espécies em Perigo de Extinção , Lagartos/classificação , Filogenia , RNA Ribossômico 16S/genética , Animais , Lagartos/genética , Filogeografia , RNA Ribossômico/genética , Índias OcidentaisRESUMO
BACKGROUND: Ligia isopods are widely distributed in the Pacific rocky intertidal shores from central California to central Mexico, including the Gulf of California. Yet, their biological characteristics restrict them to complete their life cycles in a very narrow range of the rocky intertidal supralittoral. Herein, we examine phylogeographic patterns of Ligia isopods from 122 localities between central California and central Mexico. We expect to find high levels of allopatric diversity. In addition, we expect the phylogeographic patterns to show signatures of past vicariant events that occurred in this geologically dynamic region. METHODOLOGY/PRINCIPAL FINDINGS: We sequenced two mitochondrial genes (Cytochrome Oxidase I and 16S ribosomal DNA). We conducted Maximum Likelihood and Bayesian phylogenetic analyses. We found many divergent clades that, in general, group according to geography. Some of the most striking features of the Ligia phylogeographic pattern include: (1) deep mid-peninsular phylogeographic breaks on the Pacific and Gulf sides of Baja peninsula; (2) within the Gulf lineages, the northern peninsula is most closely related to the northern mainland, while the southern peninsula is most closely related to the central-southern mainland; and, (3) the southernmost portion of the peninsula (Cape Region) is most closely related to the southernmost portion of mainland. CONCLUSIONS/SIGNIFICANCE: Our results shed light on the phylogenetic relationships of Ligia populations in the study area. This study probably represents the finest-scale phylogeographic examination for any organism to date in this region. Presence of highly divergent lineages suggests multiple Ligia species exist in this region. The phylogeographic patterns of Ligia in the Gulf of California and Baja peninsula are incongruent with a widely accepted vicariant scenario among phylogeographers, but consistent with aspects of alternative geological hypotheses and phylo- and biogeographic patterns of several other taxa. Our findings contribute to the ongoing debate regarding the geological origin of this important biogeographic region.
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Isópodes/genética , Filogenia , Animais , California , DNA Mitocondrial/genética , DNA Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Evolução Molecular , Isópodes/classificação , MéxicoRESUMO
Se hace referencia a la celebración del VI Congreso de Informática en Salud, realizado en el año 2007, y su organización a cargo del Centro Nacional de Información de Ciencias Médicas-Infomed. Se explican las adaptaciones hechas a la plataforma de Plone para su uso como herramienta para la gestión del evento. A partir de esta experiencia de personalización de un sitio Plone para la gestión de un congreso científico virtual, nos propusimos generar un nuevo producto que abarcara las virtudes de la herramienta para eventos futuros. El nuevo producto creado a partir de esta experiencia se utilizó para la celebración del VII Congreso de Informática en Salud, celebrado en 2009.
Reference is made to the holding of the Sixth Congress of Health Informatics, made in 2007, and its organization by the National Information Center Science Medical-Infomed. It explains the adaptations made to the platform Plone for use as a tool for managing the event. From this experience customization of a Plone site to manage a scientific conference virtual, we proposed to generate a new product to cover the virtues of tool future events. The new product created from this experience used for the conclusion of the Seventh Congress of Health Informatics, held in 2009.
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Congressos como Assunto , Internet , SoftwareRESUMO
The activities of short synthetic, nonhemolytic peptides derived from the C-terminal region of myotoxin II, a catalytically inactive phospholipase A2 homologue present in the venom of the snake Bothrops asper, have been shown to reproduce the bactericidal activity of the parent protein. They combine cationic and hydrophobic-aromatic amino acids, thus functionally resembling the antimicrobial peptides of innate defenses. This study evaluated the antimicrobial and antiendotoxic properties of a 13-mer derivative peptide of the C-terminal sequence from positions 115 to 129 of myotoxin II, named pEM-2. This peptide (KKWRWWLKALAKK) showed bactericidal activity against both gram-positive and gram-negative bacteria. In comparison to previously described peptide variants derived from myotoxin II, the toxicity of pEM-2 toward eukaryotic cells in culture was significantly reduced, being similar to that of lactoferricin B but lower than that of polymyxin B. The all-D enantiomer of pEM-2 [pEM-2 (D)] retained the same bactericidal potency of its L-enantiomeric counterpart, but it showed an enhanced ability to counteract the lethal activity of an intraperitoneal lipopolysaccharide challenge in mice, which correlated with a significant reduction of the serum tumor necrosis factor alpha levels triggered by this endotoxin. Lethality induced by intraperitoneal infection of mice with Escherichia coli or Salmonella enterica serovar Typhimurium was reduced by the administration of pEM-2 (D). These results demonstrate that phospholipase A2-derived peptides may have the potential to counteract microbial infections and encourage further evaluations of their actions in vivo.
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Bothrops , Venenos de Crotalídeos/enzimologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Neurotoxinas/química , Fragmentos de Peptídeos/farmacologia , Fosfolipases A/química , Animais , Linhagem Celular , Endotoxemia/tratamento farmacológico , Endotoxemia/microbiologia , Endotoxinas/metabolismo , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/metabolismo , Fosfolipases A2 do Grupo II , Humanos , Lipopolissacarídeos/metabolismo , Camundongos , Mioblastos , Testes de Neutralização , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/toxicidade , Peritonite/tratamento farmacológico , Peritonite/microbiologia , Fosfolipases A2 , Proteínas de Répteis , Salmonella typhimurium/efeitos dos fármacosRESUMO
El estudio de la incidencia y del tipo de serología positiva que provoca el rechazo de los donadores de hemo componentes, constituye una pieza fundamental en el proceso de aseguramiento de calidad en un Banco de Sangre. Basado en esta necesidad, se evaluaron los distintos motivos de rechazo de personas donantes de sangre, haciendo énfasis en el descarte por serología positiva. De los cuatro mil individuos que se atendieron en promedio en la última década, se rechazaron cerca de un 20 por ciento, siendo las serologías positivas las responsables de una cuarta parte de estos rechazos. La mayor problemática ha pasado de ser las pruebas positivas de Chagas y VDRL, a los distintos marcadores de hepatitis B y C, especialmente los anticuerpos anti-HBcore. En el período 2003-2004, los portadores crónicos de hepatitis B constituyeron la mayoría de exámenes positivos, con una incidencia del 1.8 por ciento. Si se comparan los datos obtenidos en el presente reporte con estudios similares realizados en países como Estados Unidos y Argentina, encontramos una baja incidencia de serologías positivas.
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Humanos , Sangue , Bancos de Sangue , Doadores de Sangue , Análise Química do Sangue , Sorotipagem , Costa RicaRESUMO
Lys49 phospholipase A2 homologues constitute a group of catalytically-inactive proteins, present in the venoms of many crotalid snakes, which induce myonecrosis. Current evidence supports the mapping of their toxic site to the C-terminal region, where amino acids comprised within the sequence 115-129 appear to play a central role in toxicity. This study evaluated the possible toxic effects of several synthetic peptides corresponding to the sequence 115-129 of different Lys49 myotoxins, using in vitro cytotoxicity and in vivo myotoxicity assays. Peptides varied widely in their activities, ranging from fully toxic to harmless. Thus, the toxic actions of Lys49 myotoxins cannot always be reproduced by their free peptides 115-129. Peptides from Agkistrodon p. piscivorus (AppK) and A. contortrix laticinctus Lys49 myotoxins exerted both cytotoxicity and myotoxicity. Random scrambling of peptide AppK resulted in complete loss of toxicity, demonstrating that its specific sequence of residues, rather than their simple presence or frequency, confers its ability to damage muscle. Peptide AppK synthesized with D-amino acids retained both activities of the natural L-enantiomer, suggesting that its mechanism of action does not involve the recognition of a proteic receptor/acceptor site on muscle cells, but possibly the binding to other structures, such as negatively-charged membrane phospholipids.
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Venenos de Crotalídeos/toxicidade , Mioblastos/efeitos dos fármacos , Neurotoxinas/toxicidade , Fragmentos de Peptídeos/toxicidade , Fosfolipases A/toxicidade , Animais , Células Cultivadas , Venenos de Crotalídeos/síntese química , Relação Dose-Resposta a Droga , Fosfolipases A2 do Grupo II , L-Lactato Desidrogenase/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Camundongos , Mioblastos/metabolismo , Neurotoxinas/síntese química , Fragmentos de Peptídeos/síntese química , Fosfolipases A/síntese química , Fosfolipases A2 , Conformação Proteica , Proteínas de Répteis , Testes de ToxicidadeRESUMO
Con el crecimiento desproporcionado de la Ciudad de México y el agravamiento de la crisis socioeconómico por la que le país atraviesa, el fenómeno de las bandas juveniles ha empezado a cobrar gran fuerza, llamando la atención de varios grupos de investigadores que quieren entender la peculiar problemática que se desenvuelve a su alrededor: pobreza, marginalidad y drogas por un lado; comportamientos característicos de la adolescencia, tanto destructivos como constructivos, por el otro. Sin embargo, muy pocos estudiosos se han realizado en este campo, sobre todo estudios que vayan y penetren directamamente al lugar donde habitan estos jóvenes, para investigar concretamente su mode de vida, su realidade material, la relación que existe entre ellos y los demás miembros de la comunidad, su percepción y visión del mundo. Este trabajo, realizado por cinco investigadores del Instituto Mexicano de Psiquiatría, constituye precisamente un intento de penetrar al quehacer cotidiano de una banda juvenil en una zona marginada de la Ciudad de México. Es un intento descriptivo, es decir, entrar al mundo de la banda y salir de aquél con un retrato que capture, en la mayor medida posible, algunas características de la vida de estos jóvenes. Partimos de la premisa de que para entender la problemática que representan estos agrupamientos es necesario emprender un estudio de sus conductas, pero desde el ámbito natural en donde estas se desarrollan. Por lo tanto, se diseño una investigación de tipo naturalístico, siguiendo una metodología apropiada para penetrar al mundo habitado por la banda. Se escogió la técnica de Observación Participante por medio de la cual los investigadores participan en diferentes actividades con el grupo de estudio, en este caso los jóvenes banda, e informan de todo lo hecho y de sus impresiones en diarios de campo...