262 research outputs found
A importância da microscopia electrónica no estudo taxonómico do recife algal fóssil da Prainha.
XXXVIII Reunião Anual da Sociedade Portuguesa de Microscopia Electrónica e Biologia Celular. Ponta Delgada, Açores, 5-7 de Dezembro de 2003
Checklist of the Pleistocene marine molluscs of Praínha and Lagoínhas (Santa Maria Island, Azores).
A critical review of the reported Pleistocene species of and Lagoinhas (Santa Maria Island, Azores) is provided, new data increasing the marine molluscan fauna to 95 taxa (80 Gastropoda and 15 Bivalvia). Six of the reported taxa are considered dubious
records (5 Gastropoda, 1 Bivalvia). The stratigraphic sequence of Praia Formosa is composed of two main units, about 2-4 meters above present-day sea level. In the lower unit, Patella ulyssiponensis dominates the
fossil assemblage of the basal calcareous conglomerate while Myoforceps arustatus (Dillwyn, 1817) dominates the assemblage associated to a calcareous algae mat. Above a non-depositional hiatus surface, a sandy beach deposit mainly composes the upper unit. Its fossil assemblages are dominated by large amounts of Eruilin castanea (Montagu, 1803) and, in a less extent, Lucinella diwricntn (Linnaeus, 1758) and Ensis minor (Chenu, 1843). The stratigraphic sequence of Lagoinhas, located 7.4 m above present-day sea level, is also composed of two units. A basal conglomerate is fossilized by or passes laterally to a
calcareous algae mat, dominated by Myoforceps aristatus and with abundant Calliostoma pecimens. As at Prainha, these lower units are covered by a highly fossiliferous sandy bach deposit, though thinner, in which Ervlie castanea is the dominant species. Some species with Caribbean or West African affinities, the "Strombus bubonius accompanying
fauna" (Garcia-Talavera, 1990), were found in the lower layers. The upper layer
malacofauna is mainly related to the Mediterranean faunas, similarly to what happens nowadays (Ávila, 2000)
Coralline-algal framework in the quaternary of prainha (Santa Maria island, Azores)
© Instituto Geológico y Minero de España.At the south coast of the island of Santa Maria (Azores, Portugal) a coralline-algal framework emerges near the base of a Quaternary succession. It is located about 2 m above the present mean sea level, extends for near 200 m along the littoral zone, and has a maximum thickness of 60 cm. The
main framework builders are coralline red algae (Corallinaceae, Rhodophyta). Mollusc shells, vermetid tubes and bryozoans are the secondary framework builders. The coralline assemblage is composed of Spongites fruticulosus, with some Neogoniolithon brassica-florida, Lithophyllum incrustans
and Titanoderma pustulatum. The morphological network and taxonomic composition show close analogies with the coralline algal assemblages of the Mediterranean and west Atlantic, formed at sea level in narrow tide amplitudes and moderate hydrodynamics
Identification and nutritive vale of potential fodder trees and shrubs in the mid Rift Valley of Ethiopa
The aim of this study was to identify potential browse species in the mid Rift Valley of Ethiopia and to assess their
nutritive value. A total of 120 household from four districts in the mid Rift Valley of Ethiopia were interviewed to
identify locally important browse species. Herbarium samples were collected for identification and/or confirmation of
the scientific names. Samples were also taken for chemical composition analysis. A total of 18 different browse species
were identified, which are regarded as being important for different classes of livestock. The CP value of the edible
component ranged between 8.95-20.9%, the NDF values ranged from 30.41-78.55%, the ADF values ranged from 19.42-
47.5%.,and the ADL values ranged from 7.16 to 24.68. Generally the differences in chemical composition between
different browse species were significant. These results indicate that there is a number of promising browse species in
the indigenous flora. However, apart from chemical composition, they need to be characterized further in terms of
palatability, digestibility, feed intake, animal response trials and anti-nutritional factors, in order to be able to enhance
their utilization in the future.Oromia Agricultural Research
Institutehttp://www.thejaps.org.pk/am2016Animal and Wildlife Science
Function of Metallothionein-3 in Neuronal Cells: Do Metal Ions Alter Expression Levels of MT3?
A study of factors proposed to affect metallothionein-3 (MT3) function was carried out to elucidate the opaque role MT3 plays in human metalloneurochemistry. Gene expression of Mt2 and Mt3 was examined in tissues extracted from the dentate gyrus of mouse brains and in human neuronal cell cultures. The whole-genome gene expression analysis identified significant variations in the mRNA levels of genes associated with zinc homeostasis, including Mt2 and Mt3. Mt3 was found to be the most differentially expressed gene in the identified groups, pointing to the existence of a factor, not yet identified, that differentially controls Mt3 expression. To examine the expression of the human metallothioneins in neurons, mRNA levels of MT3 and MT2 were compared in BE(2)C and SH-SY5Y cell cultures treated with lead, zinc, cobalt, and lithium. MT2 was highly upregulated by Zn2+ in both cell cultures, while MT3 was not affected, and no other metal had an effect on either MT2 or MT3
Rilonacept and Anakinra in Recurrent Pericarditis: A Systematic Review and Meta-Analysis
Interleukin 1 (IL-1) has been indicated as a mediator of recurrent pericarditis. Rilonacept, a soluble IL-1 receptor chimeric fusion protein neutralizing interleukin 1 alpha (IL-1α) and interleukin 1 beta (IL-1β), has demonstrated promising results in a phase II study in recurrent or refractory pericarditis. Anakinra is a recombinant inhibitor of the IL-1 receptor with a demonstrated reduction in the incidence of recurrent pericarditis. Definite pharmacological management of pericarditis is key to preventing recurrences, mostly treatment options for recurrent pericarditis refractory to conventional drugs. Here we critically discuss the existing therapy options for recurrent pericarditis, with a focus on new pharmacological approaches: rilonacept and anakinra. A systematic search was conducted across online databases such as PubMed, Cochrane, Google Scholar, ScienceDirect, CINAHL, Scopus, and Embase to obtain clinical trials that assess the effectiveness of anti-interleukin 1 therapy such as anakinra and rilonacept in the management of recurrent pericarditis. Our study concluded that anti-interleukin 1 therapy significantly improved both the quality of life and the clinical outcomes of the study population. These outcomes were most prominent with the use of rilonacept and anakinra in the trial treatment. Rilonacept and anakinra are valuable options in case of recurrent pericarditis refractory to conventional drugs
Climate and land-use changes reshuffle politically-weighted priority areas of mountain biodiversity
Protected areas (PAs) play a critical role in conserving biodiversity and maintaining viable populations of threatened species. Yet, as global change could reduce the future effectiveness of existing PAs in covering high species richness, updating the boundaries of existing PAs or creating new ones might become necessary to uphold conservation goals. Modelling tools are increasingly used by policymakers to support the spatial prioritization of biodiversity conservation, enabling the inclusion of scenarios of environmental changes to achieve specific targets. Here, using the Western Swiss Alps as a case study, we show how integrating species richness derived from species distribution model predictions for four taxonomic groups under present and future climate and land-use conditions into two conservation prioritization schemes can help optimize extant and future PAs. The first scheme, the “Priority Scores Method” identified priority areas for the expansion of the existing PA network. The second scheme, using the zonation software, allowed identifying priority conservation areas while incorporating global change scenarios and political costs. We found that existing mountain PAs are currently not situated in the most environmentally nor politically suitable locations when maximizing alpha diversity for the studied taxonomic groups and that current PAs could become even less optimum under the future climate and land-use change scenarios. This analysis has focused on general areas of high species richness or species of conservation concern and did not account for special habitats or functional groups that could have been used to create the existing network. We conclude that such an integrated framework could support more effective conservation planning and could be similarly applied to other landscapes or other biodiversity conservation indice
Molecular drivers of insecticide resistance in the Sahelo-Sudanian populations of a major malaria vector Anopheles coluzzii
Background:
Information on common markers of metabolic resistance in malaria vectors from countries sharing similar eco-climatic characteristics can facilitate coordination of malaria control. Here, we characterized populations of the major malaria vector Anopheles coluzzii from Sahel region, spanning four sub-Saharan African countries: Nigeria, Niger, Chad and Cameroon.
Results:
Genome-wide transcriptional analysis identified major genes previously implicated in pyrethroid and/or cross-resistance to other insecticides, overexpressed across the Sahel, including CYP450s, glutathione S-transferases, carboxylesterases and cuticular proteins. Several, well-known markers of insecticide resistance were found in high frequencies—including in the voltage-gated sodium channel (V402L, I940T, L995F, I1527T and N1570Y), the acetylcholinesterase-1 gene (G280S) and the CYP4J5-L43F (which is fixed). High frequencies of the epidemiologically important chromosomal inversion polymorphisms, 2La, 2Rb and 2Rc, were observed (~80% for 2Rb and 2Rc). The 2La alternative arrangement is fixed across the Sahel. Low frequencies of these inversions (C), between Forkhead box L1 and c-EST putative binding sites, were responsible for the high overexpression of GSTe2 in the resistant mosquitoes. Transgenic flies expressing CYP6Z2 exhibited marginal resistance towards 3-phenoxybenzylalcohol (a primary product of pyrethroid hydrolysis by carboxylesterases) and a type II pyrethroid, α-cypermethrin. However, significantly higher mortalities were observed in CYP6Z2 transgenic flies compared with controls, on exposure to the neonicotinoid, clothianidin. This suggests a possible bioactivation of clothianidin into a toxic intermediate, which may make it an ideal insecticide against populations of An. coluzzii overexpressing this P450.
Conclusions:
These findings will facilitate regional collaborations within the Sahel region and refine implementation strategies through re-focusing interventions, improving evidence-based, cross-border policies towards local and regional malaria pre-elimination
Exploring the molecular mechanisms of increased intensity of pyrethroid resistance in Central African population of a major malaria vector Anopheles coluzzii
Molecular mechanisms driving the escalation of pyrethroid resistance in the major malaria mosquitoes of Central Africa remain largely uncharacterized, hindering effective management strategies. Here, resistance intensity and the molecular mechanisms driving it were investigated in a population of Anopheles coluzzii from northern Cameroon. High levels of pyrethroid and organochloride resistance were observed in An. coluzzii population, with no mortality for 1× permethrin; only 11% and 33% mortalities for 5× and 10× permethrin diagnostic concentrations, and <2% mortalities for deltamethrin and DDT, respectively. Moderate bendiocarb resistance (88% mortality) and full susceptibility to malathion were observed. Synergist bioassays with piperonyl butoxide recovered permethrin susceptibility, with mortalities increasing to 53.39%, and 87.30% for 5× and 10× permethrin, respectively, implicating P450 monooxygenases. Synergist bioassays with diethyl maleate (DEM) recovered permethrin and DDT susceptibilities (mortalities increasing to 34.75% and 14.88%, respectively), implicating glutathione S‐transferases. RNA‐seq‐based genome‐wide transcriptional analyses supported by quantitative PCR identified glutathione S‐transferase, GSTe2 (RNA‐seqFC = 2.93 and qRT‐PCRFC = 8.4, p < 0.0043) and CYP450, CYP6Z2 (RNA‐seqFC = 2.39 and qRT‐PCRFC = 11.7, p < 0.0177) as the most overexpressed detoxification genes in the pyrethroid‐resistant mosquitoes, compared to mosquitoes of the susceptible Ngousso colony. Other overexpressed genes include P450s, CYP6M2 (FC = 1.68, p < 0.0114), CYP4G16 (FC = 2.02, p < 0.0005), and CYP4G17 (FC = 1.86, p < 0.0276). While high frequency of the 1014F kdr mutation (50%) and low frequencies of 1014S (6.61%) and 1575Y (10.29%) were observed, no ace‐1 mutation was detected in bendiocarb‐resistant populations, suggesting the preeminent role of metabolic mechanism. Overexpression of metabolic resistance genes (including GSTe2 and CYP6Z2 known to confer resistance to multiple insecticides) in An. coluzzii from the Sudan Savannah of Cameroon highlights the need for alternative management strategies to reduce malaria burden in northern Cameroon
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