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1.
Dev Biol ; 491: 56-65, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36067837

RESUMEN

Sea urchin larvae spend weeks to months feeding on plankton prior to metamorphosis. When handled in the laboratory they are easily injured, suggesting that in the plankton they are injured with some frequency. Fortunately, larval wounds are repaired through an efficient wound response with mesenchymal pigment cells and blastocoelar cells assisting as the epithelium closes. An injury to the epithelium leads to an immediate calcium transient that rapidly spreads around the entire larva and is necessary for activating pigment cell migration toward the wound. If calcium transport is blocked, the pigment cells fail to activate and remain in place. When activated, pigment cells initiate directed migration to the wound site from distances of at least 85 â€‹µm. Upon arrival at the wound site they participate in an innate immune response. Blastocoelar cells are recruited to the injury site as well, though the calcium transient is unnecessary for activating these cells. At the wound site, blastocoelar cells participate in several functions including remodeling the skeleton if it protrudes through the epithelium.


Asunto(s)
Calcio , Erizos de Mar , Animales , Epitelio , Larva , Metamorfosis Biológica
2.
Dev Biol ; 459(2): 72-78, 2020 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-31881199

RESUMEN

In the sea urchin larva, most neurons lie within an ectodermal region called the ciliary band. Our understanding of the mechanisms of specification and patterning of these peripheral ciliary band neurons is incomplete. Here, we first examine the gene regulatory landscape from which this population of neural progenitors arise in the neuroectoderm. We show that ciliary band neural progenitors first appear in a bilaterally symmetric pattern on the lateral edges of chordin expression in the neuroectoderm. Later in development, these progenitors appear in a salt-and-pepper pattern in the ciliary band where they express soxC, and prox, which are markers of neural specification, and begin to express synaptotagminB, a marker of differentiated neurons. We show that the ciliary band expresses the acid sensing ion channel gene asicl, which suggests that ciliary band neurons control the larva's ability to discern touch sensitivity. Using a chemical inhibitor of MAPK signaling, we show that this signaling pathway is required for proper specification and patterning of ciliary band neurons. Using live imaging, we show that these neural progenitors undergo small distance migrations in the embryo. We then show that the normal swimming behavior of the larvae is compromised if the neurogenesis pathway is perturbed. The developmental sequence of ciliary band neurons is very similar to that of neural crest-derived sensory neurons in vertebrates and may provide insights into the evolution of sensory neurons in deuterostomes.


Asunto(s)
Tipificación del Cuerpo/genética , Ectodermo/crecimiento & desarrollo , Neurogénesis/genética , Neuronas/metabolismo , Erizos de Mar/embriología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Butadienos/farmacología , Regulación del Desarrollo de la Expresión Génica , Glicoproteínas/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Larva/crecimiento & desarrollo , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Nitrilos/farmacología , Proteína Nodal/metabolismo , Factores de Transcripción SOXC/metabolismo , Transducción de Señal/genética , Sinaptotagminas/metabolismo
3.
Development ; 145(21)2018 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-30413529

RESUMEN

Many marine larvae begin feeding within a day of fertilization, thus requiring rapid development of a nervous system to coordinate feeding activities. Here, we examine the patterning and specification of early neurogenesis in sea urchin embryos. Lineage analysis indicates that neurons arise locally in three regions of the embryo. Perturbation analyses showed that when patterning is disrupted, neurogenesis in the three regions is differentially affected, indicating distinct patterning requirements for each neural domain. Six transcription factors that function during proneural specification were identified and studied in detail. Perturbations of these proneural transcription factors showed that specification occurs differently in each neural domain prior to the Delta-Notch restriction signal. Though gene regulatory network state changes beyond the proneural restriction are largely unresolved, the data here show that the three neural regions already differ from each other significantly early in specification. Future studies that define the larval nervous system in the sea urchin must therefore separately characterize the three populations of neurons that enable the larva to feed, to navigate, and to move food particles through the gut.


Asunto(s)
Embrión no Mamífero/metabolismo , Lytechinus/embriología , Lytechinus/metabolismo , Neurogénesis , Animales , Tipificación del Cuerpo/genética , Proteínas Morfogenéticas Óseas/metabolismo , Linaje de la Célula/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Regulación del Desarrollo de la Expresión Génica , Redes Reguladoras de Genes , Lytechinus/genética , Modelos Biológicos , Neurogénesis/genética , Proteína Nodal/metabolismo , Transducción de Señal , Factores de Transcripción/metabolismo
4.
Dev Biol ; 411(2): 314-324, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26872875

RESUMEN

Most bilaterians exhibit a left-right asymmetric distribution of their internal organs. The sea urchin larva is notable in this regard since most adult structures are generated from left sided embryonic structures. The gene regulatory network governing this larval asymmetry is still a work in progress but involves several conserved signaling pathways including Nodal, and BMP. Here we provide a comprehensive analysis of Hedgehog signaling and it's contribution to left-right asymmetry. We report that Hh signaling plays a conserved role to regulate late asymmetric expression of Nodal and that this regulation occurs after Nodal breaks left-right symmetry in the mesoderm. Thus, while Hh functions to maintain late Nodal expression, the molecular asymmetry of the future coelomic pouches is locked in. Furthermore we report that cilia play a role only insofar as to transduce Hh signaling and do not have an independent effect on the asymmetry of the mesoderm. From this, we are able to construct a more complete regulatory network governing the establishment of left-right asymmetry in the sea urchin.


Asunto(s)
Proteínas Hedgehog/fisiología , Erizos de Mar/embriología , Erizos de Mar/fisiología , Animales , Tipificación del Cuerpo , Cilios/fisiología , Embrión no Mamífero/metabolismo , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Hibridación in Situ , Cinesinas/química , Mesodermo/metabolismo , Proteína Nodal/fisiología , Oligonucleótidos Antisentido/genética , Reacción en Cadena de la Polimerasa , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo
5.
Development ; 138(15): 3297-306, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21750039

RESUMEN

In the sea urchin, entry of ß-catenin into the nuclei of the vegetal cells at 4th and 5th cleavages is necessary for activation of the endomesoderm gene regulatory network. Beyond that, little is known about how the embryo uses maternal information to initiate specification. Here, experiments establish that of the three maternal Wnts in the egg, Wnt6 is necessary for activation of endodermal genes in the endomesoderm GRN. A small region of the vegetal cortex is shown to be necessary for activation of the endomesoderm GRN. If that cortical region of the egg is removed, addition of Wnt6 rescues endoderm. At a molecular level, the vegetal cortex region contains a localized concentration of Dishevelled (Dsh) protein, a transducer of the canonical Wnt pathway; however, Wnt6 mRNA is not similarly localized. Ectopic activation of the Wnt pathway, through the expression of an activated form of ß-catenin, of a dominant-negative variant of GSK-3ß or of Dsh itself, rescues endomesoderm specification in eggs depleted of the vegetal cortex. Knockdown experiments in whole embryos show that absence of Wnt6 produces embryos that lack endoderm, but those embryos continue to express a number of mesoderm markers. Thus, maternal Wnt6 plus a localized vegetal cortical molecule, possibly Dsh, is necessary for endoderm specification; this has been verified in two species of sea urchin. The data also show that Wnt6 is only one of what are likely to be multiple components that are necessary for activation of the entire endomesoderm gene regulatory network.


Asunto(s)
Endodermo/fisiología , Regulación del Desarrollo de la Expresión Génica , Redes Reguladoras de Genes , Erizos de Mar/anatomía & histología , Erizos de Mar/embriología , Erizos de Mar/genética , Proteínas Wnt/metabolismo , Animales , Embrión no Mamífero/fisiología , Inducción Embrionaria , Técnicas de Silenciamiento del Gen , Oocitos/citología , Oocitos/fisiología , Erizos de Mar/fisiología , Transducción de Señal/fisiología , Proteínas Wnt/genética
6.
bioRxiv ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38979202

RESUMEN

Dicer substrate interfering RNAs (DsiRNAs) destroy targeted transcripts using the RNA-Induced Silencing Complex (RISC) through a process called RNA interference (RNAi). This process is ubiquitous among eukaryotes. Here we report the utility of DsiRNA in embryos of the sea urchin Lytechinus variagatus (Lv). Specific knockdowns phenocopy known morpholino and inhibitor knockdowns, and DsiRNA offers a useful alternative to morpholinos. Methods for designing and obtaining specific DsiRNAs that lead to destruction of targeted mRNA are described. DsiRNAs directed against pks1, an enzyme necessary for pigment production, show how successful DsiRNA perturbations are monitored by RNA in situ analysis and by qPCR to determine relative destruction of targeted mRNA. DsiRNA-based knockdowns phenocopy morpholino- and drug-based inhibition of nodal and lefty. Other knockdowns demonstrate that the RISC operates early in development as well as on genes that are first transcribed hours after gastrulation is completed. Thus, DsiRNAs effectively mediate destruction of targeted mRNA in the sea urchin embryo. The approach offers significant advantages over other widely used methods in the urchin in terms of cost, and ease of procurement, and offers sizeable experimental advantages in terms of ease of handling, injection, and knockdown validation.

7.
Genet Mol Biol ; 36(1): 22-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23569404

RESUMEN

Soroprevalence for Hepatitis C virus is reported as 2.12% in Northern Brazil, with about 50% of the patients exhibiting a sustained virological response (SVR). Aiming to associate polymorphisms in Killer Cell Immunoglobulin-like Receptors (KIR) with chronic hepatitis C and therapy responses we investigated 125 chronic patients and 345 controls. Additionally, 48 ancestry markers were genotyped to control for population stratification. The frequency of the KIR2DL2 and KIR2DL2+HLA-C(Asp80) gene and ligand was higher in chronic infected patients than in controls (p < 0.0009, OR = 3.4; p = 0.001, OR = 3.45). In fact, KIR2DL3 is a weaker inhibitor of NK activity than KIR2DL2, which could explain the association of KIR2DL2 with chronic infection. Moreover, KIR2DS2 and KIR2DS2+HLA-C(Asp80) (p < 0.0001, OR = 2.51; p = 0.0084, OR = 2.62) and KIR2DS3 (p < 0.0001; OR = 2.57) were associated with chronic infection, independently from KIR2DL2. No differences in ancestry composition were observed between control and patients, even with respect to therapy response groups. The allelic profile KIR2DL2/KIR2DS2/KIR2DS3 was associated with the chronic hepatitis C (p < 0.0001; OR = 3). Furthermore, the patients also showed a higher mean number of activating genes and a lower frequency of the homozygous AA profile, which is likely secondary to the association with non-AA and/or activating genes. In addition, the KIR2DS5 allele was associated with SVR (p = 0.0261; OR = 0.184).The ancestry analysis of samples ruled out any effects of population substructuring and did not evidence interethnic differences in therapy response, as suggested in previous studies.

8.
Pathog Glob Health ; 115(6): 412-422, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33956588

RESUMEN

This study aimed to describe: 1) soil-transmitted helminthiasis (STH) and schistosomiasis prevalence and intensity in preschool-age children (PSAC) and school-age children (SAC), 2) schistosomiasis seroprevalence in SAC, 3) undernutrition prevalence in SAC, 4) sanitary toilet coverage in households, and 5) association between STH, Schistosoma japonicum exposure, nutritional status, and sanitation. PSAC and SAC in two Haiyan-stricken provinces were examined using Kato-Katz technique and ELISA Antibody test. Anthropometric and hemoglobin measurements were also obtained. The reported sanitary toilet coverage was validated in a survey. The prevalence of any STH in PSAC and SAC was 50.2% and 41.3%, respectively. Moderate-heavy intensity (MHI) STH prevalence in PSAC and SAC was 20.8% and 5.9%, respectively. The prevalence of any STH, MHI STH, ascariasis, MHI ascariasis, and MHI trichuriasis was significantly higher in PSAC. Stunting, underweight, wasting, overweight/obesity, and anemia prevalence was 38.4%, 24.5%, 4.8%, 2.7%, and 34.7% in PSAC, while the prevalence was 34.3%, 21.6%, 8.7%, 3.0%, and 19.2% in SAC, respectively. Anemia and wasting prevalence were significantly higher in PSAC and SAC, respectively. There were five schistosomiasis cases found (0.8% prevalence), while schistosomiasis seroprevalence was 60.1%. Validated and reported sanitary toilet coverage was significantly different in eight out of 13 barangays. Stunting and anemia were associated with STH. STH and anemia prevalence were significantly higher in non-ZOD barangays. High STH burden in PSAC and SAC persists. A more coordinated response addressing STH, undernutrition, and WASH in disaster-stricken areas will require strengthening local health systems and promoting intersectoral collaboration.


Asunto(s)
Tormentas Ciclónicas , Helmintiasis , Helmintos , Desnutrición , Esquistosomiasis , Animales , Niño , Preescolar , Estudios Transversales , Heces , Helmintiasis/epidemiología , Humanos , Desnutrición/epidemiología , Filipinas/epidemiología , Prevalencia , Saneamiento , Esquistosomiasis/epidemiología , Estudios Seroepidemiológicos , Suelo
9.
Curr Top Dev Biol ; 136: 195-218, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31959288

RESUMEN

Gastrulation is arguably the most important evolutionary innovation in the animal kingdom. This process provides the basic embryonic architecture, an inner layer separated from an outer layer, from which all animal forms arise. An extraordinarily simple and elegant process of gastrulation is observed in the sea urchin embryo. The cells participating in sea urchin gastrulation are specified early during cleavage. One outcome of that specification is the expression of transcription factors that control each of the many subsequent morphogenetic changes. The first of these movements is an epithelial-mesenchymal transition (EMT) of skeletogenic mesenchyme cells, then EMT of pigment cell progenitors. Shortly thereafter, invagination of the archenteron occurs. At the end of archenteron extension, a second wave of EMT occurs to release immune cells into the blastocoel and primordial germ cells that will home to the coelomic pouches. The archenteron then remodels to establish the three parts of the gut, and at the anterior end, the gut fuses with the stomodaeum to form the through-gut. As part of the anterior remodeling, mesodermal coelomic pouches bud off the lateral sides of the archenteron tip. Multiple cell biological processes conduct each of these movements and in some cases the upstream transcription factors controlling this process have been identified. Remarkably, each event seamlessly occurs at the right time to orchestrate formation of the primitive body plan. This review covers progress toward understanding many of the molecular mechanisms underlying this sequence of morphogenetic events.


Asunto(s)
Embrión no Mamífero/fisiología , Transición Epitelial-Mesenquimal , Gástrula/fisiología , Gastrulación , Morfogénesis , Erizos de Mar/fisiología , Factores de Transcripción/metabolismo , Animales , Movimiento Celular , Embrión no Mamífero/citología , Gástrula/citología , Regulación del Desarrollo de la Expresión Génica , Células Germinativas , Erizos de Mar/embriología , Factores de Transcripción/genética
10.
Evodevo ; 10: 2, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30792836

RESUMEN

BACKGROUND: The sea urchin is a basal deuterostome that is more closely related to vertebrates than many organisms traditionally used to study neurogenesis. This phylogenetic position means that the sea urchin can provide insights into the evolution of the nervous system by helping resolve which developmental processes are deuterostome innovations, which are innovations in other clades, and which are ancestral. However, the nervous system of echinoderms is one of the least understood of all major metazoan phyla. To gain insights into echinoderm neurogenesis, spatial and temporal gene expression data are essential. Then, functional data will enable the building of a detailed gene regulatory network for neurogenesis in the sea urchin that can be compared across metazoans to resolve questions about how nervous systems evolved. RESULTS: Here, we analyze spatiotemporal gene expression during sea urchin neurogenesis for genes that have been shown to be neurogenic in one or more species. We report the expression of 21 genes expressed in areas of neurogenesis in the sea urchin embryo from blastula stage (just before neural progenitors begin their specification sequence) through pluteus larval stage (when much of the nervous system has been patterned). Among those 21 gene expression patterns, we report expression of 11 transcription factors and 2 axon guidance genes, each expressed in discrete domains in the neuroectoderm or in the endoderm. Most of these genes are expressed in and around the ciliary band. Some including the transcription factors Lv-mbx, Lv-dmrt, Lv-islet, and Lv-atbf1, the nuclear protein Lv-prohibitin, and the guidance molecule Lv-semaa are expressed in the endoderm where they are presumably involved in neurogenesis in the gut. CONCLUSIONS: This study builds a foundation to study how neurons are specified and evolved by analyzing spatial and temporal gene expression during neurogenesis in a basal deuterostome. With these expression patterns, we will be able to understand what genes are required for neural development in the sea urchin. These data can be used as a starting point to (1) build a spatial gene regulatory network for sea urchin neurogenesis, (2) identify how subtypes of neurons are specified, (3) perform comparative studies with the sea urchin, protostome, and vertebrate organisms.

11.
Methods Cell Biol ; 151: 177-196, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30948007

RESUMEN

A critical process in embryonic development is the activation and spatial localization of mRNAs to specific cells and territories of the embryo. Revealing the spatial distribution of mRNAs and how it changes during development is a vital piece of information that aids in understanding the signaling and regulatory genes driving specific gene regulatory networks. In the laboratory, a cost-efficient, reliable method to determine the spatial distribution of mRNAs in embryos is in situ hybridization. This sensitive and straightforward method employs exogenous antisense RNA probes to find specific and complementary sequences in fixed embryos. Antigenic moieties conjugated to the ribonucleotides incorporated in the probe cross-react with antibodies, and numerous staining methods can be subsequently employed to reveal the spatial distribution of the targeted mRNA. The quality of the data produced by this method is equivalent to the experience of the researcher, and thus a thorough understanding of the numerous steps comprising this method is important for obtaining high quality data. Here we compile and summarize several protocols that have been employed chiefly on five sea urchin species in numerous laboratories around the world. Whereas the protocols can vary for the different species, the overarching steps are similar and can be readily mastered. When properly and carefully undertaken, in situ hybridization is a powerful tool providing unambiguous data for which there currently is no comparable substitute and will continue to be an important method in the era of big data and beyond.


Asunto(s)
Desarrollo Embrionario/genética , Redes Reguladoras de Genes/genética , Hibridación in Situ/métodos , Erizos de Mar/genética , Animales , Embrión no Mamífero/citología , Regulación del Desarrollo de la Expresión Génica/genética , Larva/genética , Larva/crecimiento & desarrollo , ARN Mensajero/genética , Erizos de Mar/crecimiento & desarrollo
12.
Gac. méd. boliv ; 46(2)2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1534507

RESUMEN

Las vacunas anti-SARS-CoV-2 inducen la producción de anticuerpos neutralizantes IgG contra el Dominio de Unión al Receptor de la proteína S del virus (IgG-antiRBD). En Bolivia, Sinopharm y Sputnik V fueron vacunas ampliamente utilizadas durante la pandemia. Sin embargo, las mutaciones y los cambios sufridos en SARS-CoV-2 fueron responsables de las nuevas olas de contagio. Objetivo: determinar las alteraciones a nivel de secuencia y de estructura del RBD-SARS-CoV-2, que afectan su complementariedad por anticuerpos neutralizantes IgG-antiRBD. Material y Métodos: se obtuvieron las secuencias y estructuras cristalográficas del RBDSARS-CoV-2 a partir de la base de datos Protein Data Bank. Para el Alineamiento Múltiple de Secuencias y el Alineamiento Estructural, se emplearon Mega6 y Chimera1,15. Resultados: el Alineamiento Múltiple de Secuencias y Alineamiento Estructural de las principales variantes epidemiológicas de SARS-CoV-2 evidencian que, krakenXBB1.5 fue la más divergente a nivel de secuencia, mientras que, omicronBA2.75 presentó más cambios estructurales y mayores impedimentos estéricos al interaccionar con IgG-antiRBD, siendo la más contagiosas y más evasiva a la respuesta inmunológica. Conclusiones: el uso de herramientas bioinformáticas para el seguimiento en los cambios moleculares de SARS-CoV-2 permiten predecir el comportamiento epidemiológico de nuevas variantes emergentes y además promover el mejoramiento en los criterios de prevención.


Anti-SARS-CoV-2 vaccines induce the production of IgG neutralizing antibodies against the Receptor Binding Domain of the S protein of the virus (IgG-antiRBD). In Bolivia, Sinopharm and Sputnik V were widely used vaccines during the pandemic. However, the mutations and changes suffered in SARS-CoV-2 were responsible for the new contagion outbreaks. Objective: To determine the sequence and structure alterations of RBD-SARS-CoV-2, which affect its complementarity by IgG-antiRBD neutralizing antibodies. Material and Methods: The sequences and crystallographic structures of RBD-SARS-CoV-2 were obtained from the Protein Data Bank database. For Multiple Sequence Alignment and Structural Alignment, Mega6 and Chimera1.15 were used. Results: The Multiple Sequence Alignment and Structural Alignment of the main epidemiological variants of SARS-CoV-2 showed that krakenXBB1.5 was the most divergent at the sequence level, while omicronBA2.75 presented more structural changes and greater steric hindrances when interacting with IgG-antiRBD, being the most contagious and most evasive to the immune response. Conclusions: The use of bioinformatics tools for monitoring the molecular changes of SARS-CoV-2 make it possible to predict the epidemiological behavior of new emerging variants and also promote improvement in prevention criteria

13.
Rev Soc Bras Med Trop ; 37 Suppl 2: 57-62, 2004.
Artículo en Portugués | MEDLINE | ID: mdl-15586898

RESUMEN

The Liver Diseases Program of the Hospital Santa Casa de Misericordia do Pará was create because of the need to attend patients with liver diseases of the Amazônia area, taking as priority to attend with quality, diagnosis of aetiologies, clinical following and specific treatment. This study aim to describe dates related to epidemiology, aetiologics agents and histopathologic analysis. One thousand sixty nine patients were evaluated through medical, laboratory, endoscopic, ultrasound or computerized tomography and histopathologic examination. Nine hundred thirty five (63.6%) patients within 1469 patients were diagnose as chronic liver disease. The average age was 50 year, 666 (71.2%) were male, and the most patients lived in Belem, State of Pará. The aetiologic agents most prevail were alcoholism (53.7%) and viral hepatitis (39.1%). Hepatic biopsy were done in 403 (43.1%) within the 935 patients and the results showed chronic hepatitis (34%) and chirrosis (34%). In summary the chronic liver disease in the amazon region is more prevail in male than female, the alcoholism is the principal aetiologie, and the most of these cases were diagnose in the severe phase.


Asunto(s)
Hepatopatías/etiología , Alcoholismo/complicaciones , Brasil/epidemiología , Enfermedad Crónica , Femenino , Hepatitis Viral Humana/complicaciones , Hepatitis Viral Humana/virología , Humanos , Hepatopatías/epidemiología , Hepatopatías/virología , Masculino , Factores de Riesgo
14.
Rev Soc Bras Med Trop ; 37 Suppl 2: 33-9, 2004.
Artículo en Portugués | MEDLINE | ID: mdl-15586894

RESUMEN

Hepatitis B virus (HBV) infection presents itself with a variety of clinical manifestations. The present work aims to describe the prevalence of HBV genotypes and the occurrence of precore mutation A-1896 in a population group of the Eastern Amazon region of Brazil and to correlate them with the clinical presentation of chronic HBV infection. 51 HBsAg carriers (HBV-DNA positive) were selected and divided into three groups: A (14 asymptomatic subjects), B (20 HBeAg positive symptomatic patients) and C (17 HBeAg negative symptomatic patients). Using an automa ed DNA sequencer ABI model 377 by sequencing for determined of genotypes and precore mutation. The results showed that the genotype A was the most commonly found (81.1%, 89.5% and 93.7% in groups A, B and C, respectively) and precore mutation A-1896 was described in 11.5% (3/26) of group A subjects. Genotype A of HBV was the most prevalent (89.1%) and low occurrence of precore mutation A-1896, both not associate with the worst outcome of the chronic infection of HBV.


Asunto(s)
ADN Viral/análisis , Antígenos del Núcleo de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Mutación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , Brasil , Niño , Preescolar , Femenino , Genotipo , Antígenos del Núcleo de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Prevalencia , Carga Viral
15.
Rev Soc Bras Med Trop ; 37 Suppl 2: 47-51, 2004.
Artículo en Portugués | MEDLINE | ID: mdl-15586896

RESUMEN

In order to contribute to a better understanding of the possible role of hepatits B and C in the etiopathogenis of HCC in the East Amazon, there were studied 36 patients in Belém/PA. Serological hepatitis markers were evaluated and polymerase chain reaction assays were used to detect HBV-DNA and HCV-RNA. Alcohol abuse was observed in 33.3% and cirrhosis in 83.3%. In 88.9% of the sample, one or more hepatitis B markers were positive. Also, 8.3% those patients had anti-HCV simultaneously positive. The HBsAg serological test was positive in 58.3%; anti-HBc in 86%; anti-HBe in 85.7%; anti-HBe in 9.5%; IgM anti-HBc in 57.1%. The HBV DNA was found in 37.7% and in 65% of the HBsAg positive. The HCV RNA was detected in 8.5% and in 100% of the patients positive to anti-HCV. The AFP was above the normal value in 88.9% of patients, with levels up to 400ng/ml in 75% of them. In conclusion, hepatitis B virus infection seems to be important in the etiology of HCC and improving measures such immunization and screening in the risk population should be emphasyzed.


Asunto(s)
Carcinoma Hepatocelular/virología , Hepatitis B/complicaciones , Hepatitis C/complicaciones , Neoplasias Hepáticas/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Brasil , Niño , ADN Viral/análisis , Femenino , Anticuerpos contra la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Anticuerpos contra la Hepatitis C/sangre , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , ARN Viral/análisis
17.
Hum Immunol ; 70(9): 754-7, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19540295

RESUMEN

The present study compares the genotype frequencies between two population groups composed by 73 hepatitis C virus (HCV)-infected patients and 92 seronegative controls and investigates the role of allele variants as a possible factor in the susceptibility to HCV infection and the influence on disease progression. The identification of MBL*B and MBL*C alleles was performed by restriction fragment length polymorphism analysis of the 349-bp product using BanI and MboII restriction enzymes, respectively, and a polymerase chain reaction-sequence-specific polymorphism for discrimination of MBL*D. The analysis of allele and genotype frequencies between an HCV-infected group and seronegative controls did not indicate significant differences. The comparison of chronically infected subjects with and without liver cirrhosis was also not statistically significant. The odds ratio estimations were not significant, and the values obtained cannot suggest that the presence of allele variant MBL*B could have some influence in the risk of HCV infection progression to liver cirrhosis and that the presence of allele MBL*D could confer some protection against disease progression, but a larger sample size is necessary to confirm the present results.


Asunto(s)
Hepacivirus/inmunología , Hepatitis C Crónica/genética , Lectina de Unión a Manosa/genética , Adolescente , Adulto , Anciano , Alelos , Brasil , Análisis Mutacional de ADN , Progresión de la Enfermedad , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Hepacivirus/patogenicidad , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/fisiopatología , Humanos , Masculino , Lectina de Unión a Manosa/inmunología , Lectina de Unión a Manosa/metabolismo , Persona de Mediana Edad , Polimorfismo Genético , Factores de Riesgo , Virulencia
18.
Development ; 135(14): 2445-54, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18550713

RESUMEN

Activation of the Notch signaling pathway segregates the non-skeletogenic mesoderm (NSM) from the endomesoderm during sea urchin embryo development. Subsequently, Notch signaling helps specify the four subpopulations of NSM, and influences endoderm specification. To gain further insight into how the Notch signaling pathway is regulated during these cell specification events, we identified a sea urchin homologue of Numb (LvNumb). Previous work in other model systems showed that Numb functions as a Notch signaling pathway antagonist, possibly by mediating the endocytosis of other key Notch interacting proteins. In this study, we show that the vegetal endomesoderm expresses lvnumb during the blastula and gastrula stages, and that the protein is localized to the presumptive NSM. Injections of lvnumb mRNA and antisense morpholinos demonstrate that LvNumb is necessary for the specification of mesodermal cell types, including pigment cells, blastocoelar cells and muscle cells. Functional analysis of the N-terminal PTB domain and the C-terminal PRR domain of LvNumb shows that the PTB domain, but not the PRR domain, is sufficient to recapitulate the demonstrable function of full-length LvNumb. Experiments show that LvNumb requires an active Notch signal to function during NSM specification and that LvNumb functions in the cells responding to Delta and not in the cells presenting the Delta ligand. Furthermore, injection of mRNA encoding the intracellular domain of Notch rescues the LvNumb morpholino phenotype, suggesting that the constitutive intracellular Notch signal overcomes, or bypasses, the absence of Numb during NSM specification.


Asunto(s)
Proteínas de la Membrana/metabolismo , Mesodermo/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Receptores Notch/metabolismo , Erizos de Mar/embriología , Transducción de Señal , Secuencia de Aminoácidos , Animales , Blástula , ADN Complementario/genética , Embrión no Mamífero/citología , Embrión no Mamífero/metabolismo , Gástrula , Proteínas de la Membrana/química , Mesodermo/citología , Modelos Biológicos , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/química , Filogenia , Estructura Terciaria de Proteína , Homología de Secuencia de Aminoácido
19.
Dev Biol ; 300(1): 321-34, 2006 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-17010332

RESUMEN

Programmed cell death through apoptosis is a pan-metazoan character involving intermolecular signaling networks that have undergone substantial lineage-specific evolution. A survey of apoptosis-related proteins encoded in the sea urchin genome provides insight into this evolution while revealing some interesting novelties, which we highlight here. First, in addition to a typical CARD-carrying Apaf-1 homologue, sea urchins have at least two novel Apaf-1-like proteins that are each linked to a death domain, suggesting that echinoderms have evolved unique apoptotic signaling pathways. Second, sea urchins have an unusually large number of caspases. While the set of effector caspases (caspases-3/7 and caspase-6) in sea urchins is similar to that found in other basal deuterostomes, signal-responsive initiator caspase subfamilies (caspases-8/10 and 9, which are respectively linked to DED and CARD adaptor domains) have undergone echinoderm-specific expansions. In addition, there are two groups of divergent caspases, one distantly related to the vertebrate interleukin converting enzyme (ICE)-like subfamily, and a large clan that does not cluster with any of the vertebrate caspases. Third, the complexity of proteins containing an anti-apoptotic BIR domain and of Bcl-2 family members approaches that of vertebrates, and is greater than that found in protostome model systems such as Drosophila or Caenorhabditis elegans. Finally, the presence of Death receptor homologues, previously known only in vertebrates, in both Strongylocentrotus purpuratus and Nematostella vectensis suggests that this family of apoptotic signaling proteins evolved early in animals and was subsequently lost in the nematode and arthropod lineage(s). Our results suggest that cell survival is contingent upon a diverse array of signals in sea urchins, more comparable in complexity to vertebrates than to arthropods or nematodes, but also with unique features that may relate to specific requirements imposed by the biphasic life cycle and/or immunological idiosyncrasies of this organism.


Asunto(s)
Apoptosis/genética , Genoma , Erizos de Mar/genética , Secuencia de Aminoácidos , Animales , Caspasas/genética , Muerte Celular , Secuencia de Consenso , Modelos Biológicos , Datos de Secuencia Molecular , Filogenia , Erizos de Mar/clasificación , Erizos de Mar/citología , Erizos de Mar/fisiología , Alineación de Secuencia , Homología de Secuencia de Aminoácido
20.
Rev. Pan-Amazônica Saúde (Online) ; 1(2): 23-26, 2010. tab
Artículo en Portugués | Coleciona SUS (Brasil), LILACS | ID: biblio-945902

RESUMEN

INTRODUÇÃO: Com o advento da terapia antirretroviral de alta atividade em 1996, a doença hepática tornou-se causa importante de morbidade e mortalidade em pessoas infectadas pelo vírus da imunodeficiência humana-1 (HIV-1). OBJETIVO: Descrever os aspectos demográficos e laboratoriais de 62 pacientes coinfectados com o vírus da imunodeficiência humana e da hepatite C (HIV-1/HCV). MÉTODO: Estudo transversal, incluindo pacientes portadores do HIV, confirmados sorologicamente (ELISA + Imunofluorescência indireta ou Western Blot), com anti-HCV positivos pelo teste de ELISA confirmados por RT-PCR, atendidos no ambulatório de fígado da Fundação Santa Casa de Misericórdia do Pará no período de agosto de 2004 até abril de 2008. RESULTADOS: Foram atendidos 49 (79 por cento) indivíduos do gênero masculino e 13 indivíduos do gênero feminino, com mediana de idade de 42,6 anos, solteiros (66, por cento. n = 41), heterossexuais (59,7 por cento, n = 37), bissexuais (27,4 por cento, n = 17), homem que faz sexo com homem HSH (12,9 por cento. n = 8); contagem de linfócitos T CD4+ com mediana de 327 células/mm3, carga viral plasmática do HIV com mediana de 2,54 log10 HIV-RNA cópias/mL, carga viral do HCV (HCV-RNA) de 5,90 log10 UI/mL. O genótipo 1 do HCV foi encontrado em 60,87 por cento. A biópsia hepática foi realizada em 41 (66,12 por cento) pacientes, tendo sido observada a seguinte classificação METAVIR: F0 (12 por cento), F1 (24,4 por cento), F2 (32 por cento), F3 (17 por cento) e F4 (14,6 por cento). CONCLUSÃO: Os pacientes eram predominantemente solteiros,com carga viral do HCV elevada, apresentavam fibrose de moderada a severa em mais de 50 por cento dos casos sem alterações laboratoriais significativas...


INTRODUCTION: Since highly active antiretroviral therapy was developed in 1996, liver injury has become an important cause of morbidity and mortality in individuals infected by the human immunodeficiency virus-1 (HIV-1). OBJECTIVE: To report the demographic and laboratory findings of 62 patients coinfected with HIV-1/HCV. METHODS: This cross-sectional study analyzed HIV patients, confirmed serologically by ELISA and indirect immunofluorescence or Western Blot, with positive anti-HCV by ELISA and confirmed by RT-PCR. These patiens were treated at the Liver Department of the Fundação Santa Casa de Misericórdia do Pará from August 2004 to April 2008. RESULTS: A total of 49 (79 per cent) male and 13 female patients were analyzed. Their age median was 42.6 years and they were single (66.1 per cent n=41), heterosexual (59.7 per cent, n = 37), bisexual (27.4 per cent, n = 17), man who have sex with man MSM (12.9 per cent, n = 8); the lymphocytes T CD4+ count median was 327 cells/mm3, HIV serum viral load median was 2.54 log10 HIV RNA copies/mL, HCV viral load (RNA-HCV) was 5.9 log10 UI/mL. The HCV genotype 1 was found in 60.87 per cent of the patients. Forty-one (66.12 per cent) patients were submitted to liver biopsies and the histopathology results according to METAVIR were F0 (12 per cent), F1 (24.4 per cent), F3 (17 per cent), F4 (14.6 per cent). CONCLUSION: Patients were predominantly single, with high viral load. They presented with moderate to severe fibrosis in more than 50 per cet of cases without significant changes in their laboratory findings...


Asunto(s)
Masculino , Femenino , Humanos , VIH , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática/métodos , Hepacivirus/patogenicidad , Hepatitis C Crónica
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