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1.
Int J Syst Evol Microbiol ; 70(4): 2766-2781, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32238229

RESUMO

Two Gram-stain-negative, strictly aerobic, marine bacteria, designated as strains RKSG066T and RKSG123T, were isolated from a sponge Aplysina fistularis collected at a depth of 15 m off the west coast of San Salvador, The Bahamas. Investigation of nearly full-length 16S rRNA gene and whole genome-based phylogenies revealed that both strains belong to the order Cytophagales within the class Cytophagia and phylum Bacteroidetes. Strain RKSG066T formed a monophyletic clade with described members of the genus Fulvivirga, while strain RKSG123T formed a well-supported paraphyletic branch apart from this and other related genera within the family Flammeovirgaceae. For both RKSG066T and RKSG123T, optimal growth parameters were 30-37 °C, pH 7-8 and 2-3 % (w/v) NaCl; cells were catalase- and oxidase-positive, and flexirubin-type pigments were absent. The predominant fatty acids were iso-C15 : 0, C16 : 0, C18 : 0, iso-C17 : 0 3-OH, C16 : 1 ω5c, iso-C15 : 0 3-OH, C18 : 1 ω9c and iso-C15 : 1 G for RKSG066T, and iso-C17 : 0 3-OH, C16 : 1 ω5c, iso-C15 : 0, C16 : 0 3-OH and summed feature 4 (iso-C17 : 1 I and/or anteiso-C17 : 1 B) for RKSG123T. Menaquinone-7 was the major respiratory quinone for both strains. The DNA G+C contents of RKSG066T and RKSG123T were 39.5 and 36.7 mol%, respectively. On the basis of phylogenetic distinctiveness and polyphasic analysis, the type strain RKSG066T (=TSD-73T=LMG 29870T) is proposed to represent a novel species of the genus Fulvivirga, for which the name Fulvivirga aurantia sp. nov. is proposed. The type strain RKSG123T (=TSD-75T=LMG 30075T) is proposed to represent the type species of a novel genus and species with the proposed name Xanthovirga aplysinae gen. nov., sp. nov. Additionally, the genus Fulvivirga is emended to include strains of orange-pigmented colonies that contain the predominant cellular fatty acids C16 : 0, C18 : 0, C16  :  1 ω5c and C18  :  1 ω9c.


Assuntos
Bacteroidetes/classificação , Filogenia , Poríferos/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Bahamas , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
2.
Parasitol Res ; 119(5): 1563-1572, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32246260

RESUMO

In temperate regions, some avian haemosporidian parasites have evolved seasonal transmission strategies, with chronic infections relapsing during spring and transmission peaking during the hosts' breeding season. Because lineages with seasonal transmission strategies are unlikely to produce gametocytes in winter, we predicted that (1) resident birds living within wintering areas of Neotropical migrants would unlikely be infected with North American parasite lineages; and (2) if infected, wintering migratory birds would be more likely to harbor Plasmodium spp. rather than Parahaemoproteus spp. or Haemoproteus spp. parasites in their bloodstreams, as only Plasmodium produces life stages, other than gametocytes, that infect red blood cells. To test these predictions, we used molecular detection and microscopy to compare the diversity and prevalence of haemosporidian parasites among year-round residents and wintering migratory birds during February 2016, on three islands of The Bahamas archipelago, i.e., Andros, Grand Bahama, and Great Abaco. Infection prevalence was low and comparable between migratory (15/111) and resident (15/129) individuals, and it did not differ significantly among islands. Out of the 12 lineages detected infecting migratory birds, five were transmitted in North America; four lineages could have been transmitted during breeding, wintering, or migration; and three lineages were likely transmitted in The Bahamas. Resident birds mostly carried lineages endemic to the Caribbean region. All North American-transmitted parasite lineages detected among migratory birds were Plasmodium spp. Our findings suggest that haemosporidian parasites of migrants shift resource allocation seasonally, minimizing the production of gametocytes during winter, with low risk of infection spillover to resident birds.


Assuntos
Doenças das Aves/parasitologia , Aves/parasitologia , Haemosporida/isolamento & purificação , Plasmodium/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Migração Animal/fisiologia , Animais , Bahamas/epidemiologia , Doenças das Aves/epidemiologia , Haemosporida/classificação , Haemosporida/genética , Plasmodium/genética , Prevalência , Infecções Protozoárias em Animais/parasitologia , Estações do Ano
3.
J Fish Biol ; 96(6): 1475-1488, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32191344

RESUMO

Limited data pertaining to life history and population connectivity of the data-deficient southern stingray (Hypanus americanus) are available. To determine potential vulnerabilities of their populations, this study aimed to analyse their movement patterns and genetic variability. A population of southern stingrays encompassing nine sites around Cape Eleuthera, the Bahamas, has been monitored using mark-recapture, spanning a 2.5 year period. Out of 200 individual stingrays, more than a third were encountered again. The home range of the females appears to be restricted, which supports the notion of high site residency. As resident populations of stingrays could suffer from a lack of population connectivity and be predestined for genetic isolation and local extirpation, this study further investigated the genetic connectivity of four sample sites in the central and western Bahamas. A haplotype analysis from the mitochondrial D-loop region showed that no distinct population structure strictly correlated with the sample site. These findings were complemented by five microsatellite loci that revealed high degrees in genotypic variability and little population differentiation. The results suggest gene flow mediated by both males and females.


Assuntos
Variação Genética , Rajidae/classificação , Rajidae/genética , Migração Animal , Animais , Bahamas , Demografia , Feminino , Fluxo Gênico , Genética Populacional , Genótipo , Haplótipos , Masculino , Repetições de Microssatélites/genética
5.
Sci Rep ; 10(1): 1373, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992804

RESUMO

Quaternary paleontological and archaeological evidence often is crucial for uncovering the historical mechanisms shaping modern diversity and distributions. We take an interdisciplinary approach using multiple lines of evidence to understand how past human activity has shaped long-term animal diversity in an island system. Islands afford unique opportunities for such studies given their robust fossil and archaeological records. Herein, we examine the only non-volant terrestrial mammal endemic to the Bahamian Archipelago, the hutia Geocapromys ingrahami. This capromyine rodent once inhabited many islands but is now restricted to several small cays. Radiocarbon dated fossils indicate that hutias were present on the Great Bahama Bank islands before humans arrived at AD ~800-1000; all dates from other islands post-date human arrival. Using ancient DNA from a subset of these fossils, along with modern representatives of Bahamian hutia and related taxa, we develop a fossil-calibrated phylogeny. We found little genetic divergence among individuals from within either the northern or southern Bahamas but discovered a relatively deep North-South divergence (~750 ka). This result, combined with radiocarbon dating and archaeological evidence, reveals a pre-human biogeographic divergence, and an unexpected human role in shaping Bahamian hutia diversity and biogeography across islands.


Assuntos
DNA Antigo , Fósseis , Filogenia , Roedores , Animais , Bahamas , Humanos , Filogeografia , Roedores/classificação , Roedores/genética
7.
Zootaxa ; 4624(2): zootaxa.4624.2.3, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31716222

RESUMO

A new species of goby is described from submersible and scuba collections off Bonaire and New Providence Island, Bahamas. A molecular phylogenetic analysis of mitochondrial and nuclear genes confirms the placement of the new species within the genus Psilotris of the Nes subgroup of the Gobiosomatini. The new species is easily distinguished from congeners and morphologically similar species of Varicus by its unique coloration, which includes eight narrow, bright yellow bars on the trunk, each with a small orange spot centered on the lateral midline. In addition, the combination of the absence of scales on the head and body and the presence of modified ctenoid scales on the base of the caudal fin, branched pelvic-fin rays, and 15-16 pectoral-fin rays further differentiates the new species from other species of Psilotris and Varicus.


Assuntos
Peixes , Perciformes , Animais , Bahamas , Ilhas , Filogenia
8.
Zootaxa ; 4614(2): zootaxa.4614.2.3, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31716379

RESUMO

Petta Malmgren, 1866 is a small and poorly known genus of the annelid family Pectinariidae Quatrefages, 1866. Prior to this study, the genus comprised four species P. pusilla Malmgren, 1866 (type locality Gullmarsfjord, west coast of Sweden), P. assimilis McIntosh, 1885 (type locality between Prince Edward and Kerguelen Island, southern Indian Ocean), P. pellucida (Ehlers, 1887) (type locality Santarem Channel between Cay Sal Bank and Bahamas, Caribbean Sea) and P. tenuis Caullery, 1944 (type locality Sulu, Philippines, tropical Pacific Ocean), the two last ones were known only from the original description. We revised the genus by re-examining the types and providing updated illustrated re-descriptions of its species, except for P. assimilis of which the type material has been lost. Commonly used morphological characters of the genus are expanded to also include new ones such as the presence of pair of lateral ear-shaped lobes adjacent to dorsal base of cephalic veil, pair of ventral lappets on segment 1, pair of dorso-lateral pads on segment 5, large basal hump on branchiae, and a rounded anterior peg with a blunt tip and a longitudinal row of two major teeth on uncini. The type species P. pusilla is recognised as having four lappets on the anterior margins of cephalic veil and a large lower lip posterior to buccal cavity. Two species P. investigatoris n. sp. and P. williamsonae n. sp. are described from deep water off the coast of southeastern Australia and represent the first records of this genus in Australian waters. A phylogenetic position of one new species was assessed in the framework of a phylogeny based on a fragment of the mitochondrial cytochrome oxidase I gene (mtCOI). An updated taxonomic key to Pectinariidae genera and all species of Petta is given.


Assuntos
Anelídeos , Distribuição Animal , Animais , Austrália , Bahamas , Região do Caribe , Oceano Índico , Ilhas , Oceano Pacífico , Filipinas , Filogenia , Suécia , Índias Ocidentais
9.
Zootaxa ; 4656(2): zootaxa.4656.2.7, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31716828

RESUMO

In this study, we revise two groups of cryptic leaf litter ants, the Strumigenys nitens and Strumigenys simulans species groups. These two groups are restricted to the Greater Antilles and the Bahamas. We redefine the species groups, provide a key for the five species in the S. nitens group, and differentiate the two species in the S. simulans group. Four new species are described: Strumigenys caiman sp. nov., S. economoi sp. nov., S. hubbewatyorum sp. nov., and S. zemi sp. nov. We review and provide a key for the Strumigenys fauna of Hispaniola, which comprises the two endemic species S. economoi and S. zemi, six more broadly distributed Neotropical species, and three pan-tropical "tramp" species.


Assuntos
Formigas , Animais , Bahamas , Região do Caribe , Índias Ocidentais
10.
Philos Trans R Soc Lond B Biol Sci ; 374(1781): 20180057, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31352886

RESUMO

Modelling the dynamics of small, interconnected populations, or metapopulations, can help pinpoint habitat patches that are critical for population persistence in patchy habitats. For conservation purposes, these patches are typically earmarked for protection, but for invasive species management, these patches could be targeted to hasten the populations' demise. Here, we show how metapopulation modelling, coupled with an understanding of size-dependent dispersal behaviour, can be used to help optimize the distribution of limited resources for culling specific populations of invasive Indo-Pacific lionfish (Pterois volitans) in the western Atlantic. Through simulation using fitted model parameters, we derive three insights that can inform management. First, culling lionfish from target patches reduces the probability of lionfish occupancy at surrounding patches. Second, this effect depends on patch size and connectivity, but is strongest at the local scale and decays with distance. Finally, size-dependent dispersal in lionfish means that size-selective culling can change both a population's size distribution and dispersal potential, with cascading effects on network connectivity, population dynamics and management outcomes. By explicitly considering seascape structure and movement behaviour when allocating effort to the management of invasive species, managers can optimize resource use to improve management outcomes. This article is part of the theme issue 'Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation'.


Assuntos
Conservação dos Recursos Naturais , Peixes , Espécies Introduzidas , Movimento , Animais , Bahamas , Meio Ambiente , Dinâmica Populacional
11.
J Parasitol ; 105(4): 555-566, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31348717

RESUMO

Dispersal influences the evolution and adaptation of organisms, but it can be difficult to detect. Host-specific parasites provide information about the dispersal of their hosts and may be valuable for examining host dispersal that does not result in gene flow or that has low signals of gene flow. We examined the population connectivity of the buffy flower bat, Erophylla sezekorni (Chiroptera: Phyllostomidae), and its associated obligate ectoparasite, Trichobius frequens (Diptera: Streblidae), across a narrow oceanic channel in The Bahamas that has previously been implicated as a barrier to dispersal in bats. Due to the horizontal transmission of T. frequens, we were able to test the hypothesis that bats are dispersing across this channel, but this dispersal does not result in gene flow, occurs rarely, or started occurring recently. We developed novel microsatellite markers for the family Streblidae in combination with previously developed markers for bats to genotype individuals from 4 islands in The Bahamas. We provide evidence for a single population of the host, E. sezekorni, but 2 populations of its bat flies, potentially indicating a recent reduction of gene flow in E. sezekorni, rare dispersal, or infrequent transportation of bat flies with their hosts. Despite high population differentiation in bat flies indicated by microsatellites, mitochondrial DNA shows no polymorphism, suggesting that bacterial reproductive parasites may be contributing to mitochondrial DNA sweeps. Parasites, including bat flies, provide independent information about their hosts and can be used to test hypotheses of host dispersal that may be difficult to assess using host genetics alone.


Assuntos
Distribuição Animal/fisiologia , Quirópteros/fisiologia , Quirópteros/parasitologia , Dípteros/fisiologia , Ectoparasitoses/veterinária , Algoritmos , Alelos , Animais , Bahamas , Teorema de Bayes , Análise por Conglomerados , Sequência Consenso , DNA Mitocondrial/química , Dípteros/genética , Dípteros/microbiologia , Ectoparasitoses/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Interações Hospedeiro-Parasita , Cadeias de Markov , Alinhamento de Sequência/veterinária , Wolbachia/fisiologia
12.
Mar Pollut Bull ; 142: 145-154, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31232287

RESUMO

This study measured spatial distribution of marine debris stranded on beaches in South Eleuthera, The Bahamas. Citizen science, fetch modeling, relative exposure index and predictive mapping were used to determine marine debris source and abundance. Citizen scientists quantified debris type and abundance on 16 beaches within three coastal exposures (The Atlantic Ocean, Great Bahama Bank and The Exuma Sound) in South Eleuthera. Marine debris, (~2.5 cm or larger) on each beach was monitored twice between March-May and September-November 2013 at the same locations using GPS. Approximately, 93% of all debris items were plastic with plastic fragments (≤2.5 cm) being the most common. There were spatial differences (p ≤ 0.0001) in plastic debris abundance between coastal exposures. Atlantic Ocean beaches had larger quantities of plastic debris by weight and by meter (m) of shoreline. Stranded plastic may be associated with Atlantic Ocean currents associated with leakage from the North Atlantic sub-tropical gyre.


Assuntos
Resíduos/análise , Poluentes Químicos da Água/análise , Oceano Atlântico , Bahamas , Praias , Participação da Comunidade , Monitoramento Ambiental/métodos , Plásticos/análise
13.
J Psychosoc Oncol ; 37(5): 665-675, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31107194

RESUMO

Purpose: The purpose of this research was to examine the correlates of dysfunctional career thoughts (DCTs) in a sample of breast cancers survivors. Sample and design: A total of 195 breast cancer survivors from the Bahamas completed a cross-sectional survey. Methods: The Career Thoughts Inventory (CTI) and standard medical and demographic items were administered. Analysis of Variance and logistic regression models were used to examine associations. Findings: Total CTI scores differed by age group, marital status, surgical remedy, and employment prior to diagnosis. The odds of DCT were higher among younger (Odds Ratio [OR] = 4.4), married (OR = 2.4), who were unemployed prior to diagnosis (OR = 3.5). Conclusion: Dysfunctional career thoughts appear to be common in certain breast cancer survivors. Further research is needed to determine whether similar associations are observed in other samples. Implications for Providers: Providers should discuss DCTs after treatment.


Assuntos
Neoplasias da Mama/terapia , Sobreviventes de Câncer/psicologia , Emprego/psicologia , Adolescente , Adulto , Bahamas , Sobreviventes de Câncer/estatística & dados numéricos , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
14.
Oecologia ; 189(4): 1005-1015, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30850885

RESUMO

We utilized natural experiment opportunities presented by differential conditions (presence/absence of seabirds and invasive species) on cays in the Bahamas to study whether interisland variations in food resources contributed to gigantism in Allen Cays Rock Iguanas (Cyclura cychlura inornata). We analyzed the stable carbon (δ13C) and nitrogen (δ15N) isotope values from iguana tissues and resources from each island food web to test the predictions that (1) food webs on islands with seabirds exhibit the influence of marine subsidies from seabird guano, whereas those from non-seabird islands do not, and (2) size differences in iguanas among cays were due to either (a) supplemental food availability from mice and/or seabird carcasses killed by barn owls (Tyto alba) and/or (b) access to more nutrient-rich vegetation fertilized by seabird guano. Food web components from the seabird island (Allen Cay) had 5-9‰ higher δ15N values than those on the other cays and Allen Cay plants contained nearly two times more nitrogen. Bayesian stable isotope mixing models indicated that C3 plants dominated iguana diets on all islands and showed no evidence for consumption of mice or shearwaters. The iguanas on Allen Cay were ~ 2 times longer (48.3 ± 11.6 cm) and ~ 6 times heavier (5499 ± 2847 g) than iguanas on other cays and this was likely from marine-derived subsidies from seabird guano which caused an increase in nitrogen concentration in the plants and a resultant increase in the δ15N values across the entire food web relative to non-seabird islands.


Assuntos
Tamanho Corporal , Iguanas , Animais , Bahamas , Teorema de Bayes , Espécies Introduzidas , Ilhas , Camundongos
15.
In. The University of the West Indies, Faculty of Medical Sciences. Faculty of Medical Sciences, Research Day. St. Augustine, Caribbean Medical Journal, March 21, 2019. .
Não convencional em Inglês | MedCarib | ID: biblio-1046261

RESUMO

Objective: To compare biomedical research productivity among selected CARICOM countries. Design and Methodology: Biomedical publications of the selected CARICOM countries (Bahamas, Barbados, Dominica, Guyana, Grenada, Haiti, Jamaica, Suriname, and Trinidad & Tobago) were retrieved using 'PubMed' and 'ScImago Journal & country Rank' (SJR) databases. The publications for each country were then normalized by factors such as total population, gross domestic product (GDP) and Internet usage rate. Results: Total number of papers published by all 9 countries was 7,281 and 8,378 in PubMed (1990- 2015) and SJR databases (1996-2017) respectively. Jamaica produced highest number of biomedical publications [PubMed: 3,928 (54%) and SJR: 2,850 (34%)]. However, when adjusted, Grenada had the highest research publications per million populations, per billion GDP and per 1,000 Internet users in both databases. For trend analysis, PubMed showed that Jamaica produced highest number of additional publications each year ­ on an average 4.8 followed by Trinidad & Tobago (4.4). According to SJR, Jamaica had also highest number of citations (42,311) and H-index (76) followed by Trinidad & Tobago (29,152 and 71). Barbados had the highest number of citations per document (24.9) followed by Haiti (18.4). Conclusion: There was a marked imbalance noted among the CARICOM countries in terms of biomedical research and publications. A CARICOM-wide research may be embarked to explore disparities in biomedical research productivity and thus formulate informed health policies to alleviate diseases and eradicate poverty.


Assuntos
Pesquisa Biomédica , Suriname , Bahamas , Trinidad e Tobago , Barbados , Região do Caribe/etnologia , Dominica , Guiana , Haiti , Jamaica
16.
Zootaxa ; 4550(1): 135-140, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30790882

RESUMO

The Bahama endemic field cricket, Gryllus bryanti Morse, 1905, previously known from only the lost female holotype, is redescribed, including designation of a neotype. Known only from Andros and Eleuthera Islands in The Bahamas, where it occurs with G. assimilis, it can be separated from the latter by song, tegmen file characteristics, head wider than pronotum, and genetics.


Assuntos
Gryllidae , Ortópteros , Animais , Bahamas , Feminino , Cabeça
17.
Ann Rev Mar Sci ; 11: 491-516, 2019 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-30089226

RESUMO

Great Bahama Bank (GBB) is the principal location of the formation and accumulation of ooids (concentrically coated, sand-size carbonate grains) in the world today, and as such has been the focus of studies on all aspects of ooids for more than half a century. Our view from a close look at this vast body of literature coupled with our continuing interests stresses that biological mechanisms (microbially mediated organomineralization) are very important in the formation of ooids, whereas the controlling factor for the distribution and size of ooid sand bodies is the physical energy. Mapping and coring studies of the modern ooid sand bodies on GBB provide insight into the rock record from different perspectives. An important consequence of the dual influence of ooid formation and distribution is that the geochemical signature of ooids is not in equilibrium with the seawater in which ooids form; therefore, extracting the paleophysical energy record from oolitic deposits is potentially more accurate than doing so for the paleochemical record.


Assuntos
Carbonatos/análise , Sedimentos Geológicos/química , Modelos Teóricos , Água do Mar/análise , Oceano Atlântico , Bahamas
18.
J Fish Biol ; 94(1): 173-177, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30393865

RESUMO

An intact and uncompromised internal acoustic transmitter was non-lethally recovered from a lemon shark Negaprion brevirostris, after 13 years at liberty. The shark, first tagged at an estimated age of 2 years old near South Bimini, Bahamas in 2004, was recaptured in 2017 with a total length of 264 cm. The tagged shark displayed typical growth rate, pregnancy, natal homing and pupping behaviour of other individuals in this population. This observation provides important evidence regarding the effects from long-term retention of implanted acoustic transmitters in a carcharhinid shark.


Assuntos
Conservação dos Recursos Naturais/métodos , Tubarões/fisiologia , Telemetria/efeitos adversos , Animais , Bahamas , Liberdade , Tubarões/cirurgia , Fatores de Tempo
19.
Zootaxa ; 4524(4): 401-439, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30486103

RESUMO

Four cribrilinid bryozoans associated with deep-water corals (578-682 m depth) from the Great Bahama Bank slope, are described, two of them are new. The generic allocation of some species prompted us to raise the subgenera Puellina, Cribrilaria, and Glabrilaria to genus rank. The new combination Cribrilaria saginata (Winston, 2005) n. comb. is proposed. Genus Glabrilaria is reported from the NW Atlantic for the first time based on the description of Glabrilaria hirsuta Rosso n. sp. and Glabrilaria polita Rosso n. sp. The new genus Teresaspis Rosso n. gen. is erected, and Teresaspis lineata (Canu Bassler, 1928) n. comb. is proposed as its type species. The new genus Harmelinius Rosso n. gen. is erected for Cribrilina uniserialis (Harmelin, 1978). Both genera have uniserial colonies formed by slightly caudate zooids with extensive gymnocyst and a frontal shield of flattened costae. Teresaspis lineata n. comb., however, has costae with pelmatidia that are connected by few intercostal bridges and separated by intercostal spaces, four orificial costa-like processes with the proximal pair arching above the orifice, hyperstomial acleithral ovicells with a pseudoporous ooecium formed by the distal zooid or a kenozooid, two types of kenozooids (large with costate frontal shield and small with smooth shield and central opesia), and an ancestrula with costate frontal shield. Avicularia are apparently absent in this species. In contrast, the type species of Harmelinius Rosso n. gen. has costae lacking pelmatidia and which are separated by slit-like intercostal spaces. The hyperstomial cleithral ovicells have smooth ooecia with a median suture and without pseudopores, and are formed by a distal kenozooid associated with a small avicularium. Additional paired oral avicularia are occasionally present, as are large kenozooids with a central opesia. Oral spines or spine-like processes are absent. Taxonomy of the above reported cribrilinid genera is discussed in detail together with the geographic distribution of all mentioned taxa.


Assuntos
Antozoários , Briozoários , Animais , Bahamas , Ecossistema , Água
20.
J Org Chem ; 83(22): 13670-13677, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30280573

RESUMO

Three decahydroisoquinoline alkaloids, lepadins I-K, were isolated from a specimen of Didemnum sp. collected in the Bahamas. The structures of the new compounds were assigned by an integrated analysis of MS, IR, and 1H, 13C, and 2D NMR spectra. Like previously reported lepadins, the structures of the new compounds contain a decahydroquinoline heterocyclic core in lepadin I, and a new variation, an octahydroquinoline in lepadin J, but differ from earlier reported compounds by acylation of the 3-hydroxyl group by a rare 3'-methylthioacrylate. The absolute configuration of lepadin I was solved by interpretation of NOE measurements, and exciton coupled circular dichroism (ECCD) of the corresponding N- p-bromobenzoyl derivative. The latter constitutes a general method for determination of absolute configuration of the entire lepadin family. The configuration of the remote side-chain secondary carbinol was solved by the modified Mosher's esters method. Lepadin I inhibited butyrylcholineesterase (BuChE, IC50 3.1 µM), but only weakly inhibited acetylcholineesterase (AChE) (10% at 100 µM).


Assuntos
Alcaloides/química , Isoquinolinas/química , Quinolinas/química , Urocordados/química , Animais , Bahamas , Modelos Moleculares , Estrutura Molecular
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