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1.
BMC Genomics ; 20(1): 855, 2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31726983

RESUMEN

BACKGROUND: Annelids exhibit remarkable postembryonic developmental abilities. Most annelids grow during their whole life by adding segments through the action of a segment addition zone (SAZ) located in front of the pygidium. In addition, they show an outstanding ability to regenerate their bodies. Experimental evidence and field observations show that many annelids are able to regenerate their posterior bodies, while anterior regeneration is often limited or absent. Syllidae, for instance, usually show high abilities of posterior regeneration, although anterior regeneration varies across species. Some syllids are able to partially restore the anterior end, while others regenerate all lost anterior body after bisection. Here, we used comparative transcriptomics to detect changes in the gene expression profiles during anterior regeneration, posterior regeneration and regular growth of two syllid species: Sphaerosyllis hystrix and Syllis gracilis; which exhibit limited and complete anterior regeneration, respectively. RESULTS: We detected a high number of genes with differential expression: 4771 genes in S. hystrix (limited anterior regeneration) and 1997 genes in S. gracilis (complete anterior regeneration). For both species, the comparative transcriptomic analysis showed that gene expression during posterior regeneration and regular growth was very similar, whereas anterior regeneration was characterized by up-regulation of several genes. Among the up-regulated genes, we identified putative homologs of regeneration-related genes associated to cellular proliferation, nervous system development, establishment of body axis, and stem-cellness; such as rup and JNK (in S. hystrix); and glutamine synthetase, elav, slit, Hox genes, ß-catenin and PL10 (in S. gracilis). CONCLUSIONS: Posterior regeneration and regular growth show no significant differences in gene expression in the herein investigated syllids. However, anterior regeneration is associated with a clear change in terms of gene expression in both species. Our comparative transcriptomic analysis was able to detect differential expression of some regeneration-related genes, suggesting that syllids share some features of the regenerative mechanisms already known for other annelids and invertebrates.


Asunto(s)
Anélidos/genética , Perfilación de la Expresión Génica , Regeneración/genética , Transcriptoma , Animales , Anélidos/anatomía & histología , Biología Computacional/métodos , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento
2.
PLoS One ; 14(4): e0214211, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30970025

RESUMEN

Amblyosyllis is a worldwide distributed group of annelids mainly found in coastal environments. It is well known among the polychaete specialists mostly because of its notable beauty, showing bright colourful patterns and outstanding long and coiled appendices. Amblyosyllis is a monophyletic genus easy to identify due to its distinct diagnostic features; however, the species and their boundaries are, in most cases, not well defined. Herein, we provide an extensive sample of Amblyosyllis material (115 specimens) from several world geographic areas. We have studied the morphological features of each specimen and photographed them alive. Two mitochondrial DNA markers (COI and 16S) and one nuclear gene fragment (28S, D1 region) were sequenced. We performed phylogenetic analyses based on each DNA partition, as well as the combined data sets, obtaining congruent results. Species delimitation methods such as distance analyses, statistical parsimony networks and multi-rate Poisson tree processes were also applied. The combined results obtained from different methodologies and data sets are used to differentiate between, at least, 19 lineages compatible with the separately evolving meta-populations species concept. Four of these lineages are identified as nominal species, including the type species of Amblyosyllis, A. rhombeata. For three other lineages previously synonymized names are recovered, and seven lineages are described as new species. All of these species are described and supported by appropriate iconography. We recognize several morphological characters useful to identify species of Amblyosyllis, which in some cases should also be combined with molecular methods for species delineation. The genetic divergence in the genus is high, contrary to the morphological homogeneity observed. Two species show a wide geographical distribution, while the rest have a more restricted distribution. There are several examples of species with overlapping distribution patterns.


Asunto(s)
Anélidos/anatomía & histología , Filogenia , Filogeografía , Poliquetos/genética , Animales , Anélidos/clasificación , Anélidos/genética , ADN Mitocondrial/genética , Poliquetos/clasificación , Especificidad de la Especie
3.
Lancet Infect Dis ; 12(11): 837-44, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22954655

RESUMEN

BACKGROUND: Zanzibar, in east Africa, has been severely and repeatedly affected by cholera since 1978. We assessed the effectiveness of oral cholera vaccination in high-risk populations in the archipelago to estimate the indirect (herd) protection conferred by the vaccine and direct vaccine effectiveness. METHODS: We offered two doses of a killed whole-cell B-subunit cholera vaccine to individuals aged 2 years and older in six rural and urban sites. To estimate vaccine direct protection, we compared the incidence of cholera between recipients and non-recipients using generalised estimating equations with the log link function while controlling for potential confounding variables. To estimate indirect effects, we used a geographic information systems approach and assessed the association between neighbourhood-level vaccine coverage and the risk for cholera in the non-vaccinated residents of that neighbourhood, after controlling for potential confounding variables. This study is registered with ClinicalTrials.gov, number NCT00709410. FINDINGS: Of 48,178 individuals eligible to receive the vaccine, 23,921 (50%) received two doses. Between February, 2009, and May, 2010, there was an outbreak of cholera, enabling us to assess vaccine effectiveness. The vaccine conferred 79% (95% CI 47-92) direct protection against cholera in participants who received two doses. Indirect (herd) protection was shown by a decrease in the risk for cholera of non-vaccinated residents within a household's neighbourhood as the vaccine coverage in that neighbourhood increased. INTERPRETATION: Our findings suggest that the oral cholera vaccine offers both direct and indirect (herd) protection in a sub-Saharan African setting. Mass oral cholera immunisation campaigns have the potential to provide not only protection for vaccinated individuals but also for the unvaccinated members of the community and should be strongly considered for wider use. Because this is an internationally-licensed vaccine, we could not undertake a randomised placebo-controlled trial, but the absence of vaccine effectiveness against non-cholera diarrhoea indicates that the noted protection against cholera could not be explained by bias. FUNDING: Bill & Melinda Gates Foundation, Swedish International Development Cooperation Agency, and the South Korean Government.


Asunto(s)
Vacunas contra el Cólera/administración & dosificación , Vacunas contra el Cólera/inmunología , Cólera/epidemiología , Cólera/prevención & control , Vacunación Masiva/métodos , Administración Oral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Inmunidad Colectiva , Incidencia , Masculino , Persona de Mediana Edad , Tanzanía/epidemiología , Resultado del Tratamiento , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología , Adulto Joven
4.
PLoS Negl Trop Dis ; 6(7): e1743, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22848772

RESUMEN

INTRODUCTION: Mass vaccinations are a main strategy in the deployment of oral cholera vaccines. Campaigns avoid giving vaccine to pregnant women because of the absence of safety data of the killed whole-cell oral cholera (rBS-WC) vaccine. Balancing this concern is the known higher risk of cholera and of complications of pregnancy should cholera occur in these women, as well as the lack of expected adverse events from a killed oral bacterial vaccine. METHODOLOGY/PRINCIPAL FINDINGS: From January to February 2009, a mass rBS-WC vaccination campaign of persons over two years of age was conducted in an urban and a rural area (population 51,151) in Zanzibar. Pregnant women were advised not to participate in the campaign. More than nine months after the last dose of the vaccine was administered, we visited all women between 15 and 50 years of age living in the study area. The outcome of pregnancies that were inadvertently exposed to at least one oral cholera vaccine dose and those that were not exposed was evaluated. 13,736 (94%) of the target women in the study site were interviewed. 1,151 (79%) of the 1,453 deliveries in 2009 occurred during the period when foetal exposure to the vaccine could have occurred. 955 (83%) out of these 1,151 mothers had not been vaccinated; the remaining 196 (17%) mothers had received at least one dose of the oral cholera vaccine. There were no statistically significant differences in the odds ratios for birth outcomes among the exposed and unexposed pregnancies. CONCLUSIONS/SIGNIFICANCE: We found no statistically significant evidence of a harmful effect of gestational exposure to the rBS-WC vaccine. These findings, along with the absence of a rational basis for expecting a risk from this killed oral bacterial vaccine, are reassuring but the study had insufficient power to detect infrequent events. TRIAL REGISTRATION: ClinicalTrials.gov NCT00709410.


Asunto(s)
Toxina del Cólera/efectos adversos , Toxina del Cólera/inmunología , Vacunas contra el Cólera/efectos adversos , Vacunas contra el Cólera/inmunología , Adolescente , Adulto , Niño , Preescolar , Toxina del Cólera/administración & dosificación , Toxina del Cólera/genética , Vacunas contra el Cólera/administración & dosificación , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Femenino , Humanos , Recién Nacido , Masculino , Persona de Mediana Edad , Embarazo , Tanzanía , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/efectos adversos , Vacunas de Productos Inactivados/inmunología , Adulto Joven
5.
Zoolog Sci ; 26(9): 646-55, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19799516

RESUMEN

The genus Haplosyllides was considered as monotypic, with H. floridana as the only valid species. The present revision Includes two more species in this genus: H. aberrans comb. nov. and H. ophiocomae sp. nov. Syllis (Haplosyllis) aberrans (from Vietnam) was considered a Junior synonym of H. floridana (from the Caribbean). The finding of additional specimens from Vietnam and Indonesia, and the study of the type series, allowed us to redescribe H. aberrans comb. nov. on the basis of morphological, ecological and biogeographical characteristics. Haplosyllides aberrans comb. nov. differs from H. floridana in having posterior simple chaetae with tips twice as long, a pharyngeal tooth in all non-reproductive Individuals, and the granules Inside the dorsal cirri oval, elongated, and roughly distributed in longitudinal parallel rows. Haplosyllides ophiocomae sp. nov. was previously reported (as H. aberrans) from Puerto Rico. Although geographically close, It differs from H. floridana in having serration on the upper edge of the major teeth of simple chaetae, relatively shorter dorsal cirri, and a distinct mode of life. Haplosyllides floridana lives as an endosimbiont of Xetospongia muta, H. aberrans comb. nov. as a facultative parasite of Platycaris latirostris, and H. ophiocomae sp. nov. as a commensal of Ophiocoma pumila and other brittle stars. The meaning of these associations is discussed in light of the available Information. The remaining records of "Haplosyllides aberrans" from the Marshall Islands (associated with corals of the genus Heliopora) and from Brazil (among corals and calcareous algae) are considered as doubtful.


Asunto(s)
Poliquetos/clasificación , Poliquetos/fisiología , Animales , Poliquetos/ultraestructura
6.
Vaccine ; 26(51): 6529-41, 2008 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-18805453

RESUMEN

We analysed country recommendations and funding plans finalized through January 2008 for the inclusion of quadrivalent and bivalent human papillomavirus (HPV) vaccines in national immunization programmes. Fifteen industrialized countries have recommended HPV vaccine use based on careful review of scientific evidence and cost-effectiveness. There was a strong consensus among the guidelines regarding assessment of vaccine safety and efficacy, selection of primary target populations for vaccination, vaccine delivery strategies, and the need for vaccinated females to seek cervical cancer screening. The analysis informs ongoing discussions in several countries considering HPV vaccines for national immunization programmes and discussions at the World Health Organization about global recommendations for HPV vaccine use for national immunization programmes.


Asunto(s)
Países Desarrollados , Directrices para la Planificación en Salud , Política de Salud , Programas de Inmunización/tendencias , Vacunas contra Papillomavirus/administración & dosificación , Femenino , Humanos , Programas de Inmunización/economía , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/economía , Organización Mundial de la Salud
7.
Rev. biol. trop ; 54(3): 725-743, sept. 2006. ilus
Artículo en Español | LILACS | ID: lil-492319

RESUMEN

During a study carried out on soft bottoms from Coiba National Park (Panama), 218 specimens of syllids (Annelida: Polychaeta) belonging to 19 interstitial species have been identified. Two species are new reports for the Pacific Ocean, Exogone (Exogone) arenosa Perkins, 1981 and Streptosyllis websteri Southern, 1914; five are new for Panama, E. (E.) dispar (Webster, 1879); E. (E.) longicornis Westheide, 1974; Salvatoria mediodentata (Westheide, 1974); Pionosyllis heterocirrata (Hartmann-Schrõder, 1959) and Syllis glarearia (Westheide, 1974). A characteristic not mentioned in the original description is herein reported for E. (E.) longicornis: the presence of triangular subterminal processes in the spiniger-like compound chaetae of chaetiger one. Specimens of the species Syllis botosaneanui Hartmann-Schrõder, 1973 harboring inside embryos of various stages of development have been found; this is the first report for this species as viviparous. Lastly, one specimen of the genus Syllis has been found that is mainly characterized by its long pharynx, two dorsal prostomial lobes, and compound chaetae with short blades and long spinulation. Because we consider that one specimen is not sufficient to describe a new species we refer it as Syllis sp.


Durante un estudio sobre la fauna marina del Parque Nacional de Coiba (Panamá) se identificaron 281 ejemplares de sílidos (Annelida: Polychaeta) intersticiales pertenecientes a 19 especies. Dos son nuevas citas para el Pacífico, Exogone (Exogone) arenosa Perkins, 1981 y Streptosyllis websteri Southern, 1914; cinco son nuevas citas para Panamá, E. (E.) dispar (Webster, 1879), E. (E.) longicornis Westheide, 1974, Salvatoria mediodentata (Westheide, 1974); Pionosyllis heterocirrata (Hartmann-Schröder, 1959) y Syllis glarearia (Westheide, 1974). Se describe un caracter no presente en la descripción original de E. Longicornis, la presencia de procesos triangulares subterminales en la primera pseudospinígera. Se describen ejemplares de la especie Syllis botosaneanui Hartmann-Schröder, 1973 con embriones en diverso estado de desarrollo en su interior, por lo que se trata de la primera referencia de esta especie como vivípara. Por último, se describe un ejemplar de Syllis sp., que se caracteriza fundamentalmente por la posesión de una larga faringe, dos lóbulos prostomiales dorsales y por sus sedas compuestas de artejos cortos y larga espinulación. Estas características diferencian a Syllis sp. de cualquier especie del género pero no se describe como especie nueva por disponerse únicamente de un solo ejemplar.


Asunto(s)
Animales , Poliquetos/anatomía & histología , Conservación de los Recursos Naturales , Panamá , Poliquetos/clasificación
8.
Vaccine ; 24(22): 4692-700, 2006 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-16621189

RESUMEN

This paper reviews the current status of research and development of vaccines against meningococcal disease due to Neisseria meningitidis, a major cause of severe meningitis and septicemia with epidemic potential. While five serogroups (A, B, C, Y, and W135) are responsible for most of the disease, Group A remains unique in its ability to cause large scale epidemics mainly in Africa but also in Asia. The majority of cases in Europe and America are due to Groups B and C. The successful experience with Hib and pneumococcal conjugate vaccines has paved the way for the development of polysaccharide conjugate vaccines for the prevention of meningococcal disease. Widespread vaccination with Group C conjugate vaccines now in use in several European countries indicates that these vaccines are immunogenic, induce immunological memory, reduce colonization and provide herd immunity to the general population. A monovalent group A conjugate vaccine being developed at an affordable price, offers hope for the elimination of large epidemics in African countries. Multivalent (A, C, Y, W) conjugate vaccines are being developed, and one has already been licensed. However, effective global prevention of meningococcal disease will not be achievable without the development of a vaccine against Group B meningitis, for which outer membrane protein vaccines are under development.


Asunto(s)
Vacunas Meningococicas/inmunología , Animales , Cápsulas Bacterianas/inmunología , Costo de Enfermedad , Humanos , Neisseria meningitidis Serogrupo B/inmunología , Vacunas Conjugadas/inmunología
9.
Rev Biol Trop ; 54(3): 725-43, 2006 Sep.
Artículo en Español | MEDLINE | ID: mdl-18491613

RESUMEN

During a study carried out on soft bottoms from Coiba National Park (Panama), 218 specimens of syllids (Annelida: Polychaeta) belonging to 19 interstitial species have been identified. Two species are new reports for the Pacific Ocean, Exogone (Exogone) arenosa Perkins, 1981 and Streptosyllis websteri Southern, 1914; five are new for Panama, E. (E.) dispar (Webster, 1879); E. (E.) longicornis Westheide, 1974; Salvatoria mediodentata (Westheide, 1974); Pionosyllis heterocirrata (Hartmann-Schröder, 1959) and Syllis glarearia (Westheide, 1974). A characteristic not mentioned in the original description is herein reported for E. (E.) longicornis: the presence of triangular subterminal processes in the spiniger-like compound chaetae of chaetiger one. Specimens of the species Syllis botosaneanui Hartmann-Schröder, 1973 harboring inside embryos of various stages of development have been found; this is the first report for this species as viviparous. Lastly, one specimen of the genus Syllis has been found that is mainly characterized by its long pharynx, two dorsal prostomial lobes, and compound chaetae with short blades and long spinulation. Because we consider that one specimen is not sufficient to describe a new species we refer it as Syllis sp.


Asunto(s)
Poliquetos/anatomía & histología , Animales , Conservación de los Recursos Naturales , Panamá , Poliquetos/clasificación
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