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1.
Animals (Basel) ; 14(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38338040

RESUMO

Determining molecular markers for parasites provides a useful tool for their identification, particularly for larval stages with few distinguishable diagnostic characters. Avian cestodes play a key role in the food webs and biodiversity of hypersaline wetlands, yet they remain understudied. Using naturally infected Artemia, we identified cestode larvae (cysticercoids), assessed their genetic diversity, and explored phylogenetic relationships in relation to larval morphology and waterbird final hosts. We obtained partial 18S rDNA sequences for 60 cysticercoids of the family Hymenolepidae infecting Artemia spp. from seven localities and three countries (Spain, the USA, and Chile). We present the first DNA sequences for six taxa: Confluaria podicipina, Fimbriarioides sp., Flamingolepis liguloides, Flamingolepis sp. 1, Flamingolepis sp. 2, and Hymenolepis californicus. Intraspecific sequence variation (0.00-0.19% diversity) was lower than intergroup genetic distance (0.7-14.75%). Phylogenetic analysis revealed three main clades: 1-Flamingolepis, 2-Fimbriarioides, 3-Confluaria and Hymenolepis, all of which separated from hymenolepidids from mammals and terrestrial birds. This clear separation among taxa is congruent with previous morphological identification, validating the 18S gene as a useful marker to discriminate at generic/species level. Working with intermediate hosts allows the expansion of knowledge of taxonomic and genetic diversity of cestodes in wildlife, as well as elucidation of their life cycles.

2.
Genes (Basel) ; 14(4)2023 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-37107634

RESUMO

The blue mussel Mytilus chilensis is an endemic and key socioeconomic species inhabiting the southern coast of Chile. This bivalve species supports a booming aquaculture industry, which entirely relies on artificially collected seeds from natural beds that are translocated to diverse physical-chemical ocean farming conditions. Furthermore, mussel production is threatened by a broad range of microorganisms, pollution, and environmental stressors that eventually impact its survival and growth. Herein, understanding the genomic basis of the local adaption is pivotal to developing sustainable shellfish aquaculture. We present a high-quality reference genome of M. chilensis, which is the first chromosome-level genome for a Mytilidae member in South America. The assembled genome size was 1.93 Gb, with a contig N50 of 134 Mb. Through Hi-C proximity ligation, 11,868 contigs were clustered, ordered, and assembled into 14 chromosomes in congruence with the karyological evidence. The M. chilensis genome comprises 34,530 genes and 4795 non-coding RNAs. A total of 57% of the genome contains repetitive sequences with predominancy of LTR-retrotransposons and unknown elements. Comparative genome analysis of M. chilensis and M. coruscus was conducted, revealing genic rearrangements distributed into the whole genome. Notably, transposable Steamer-like elements associated with horizontal transmissible cancer were explored in reference genomes, suggesting putative relationships at the chromosome level in Bivalvia. Genome expression analysis was also conducted, showing putative genomic differences between two ecologically different mussel populations. The evidence suggests that local genome adaptation and physiological plasticity can be analyzed to develop sustainable mussel production. The genome of M. chilensis provides pivotal molecular knowledge for the Mytilus complex.


Assuntos
Mytilus edulis , Mytilus , Animais , Mytilus/genética , Chile , Aquicultura , Cromossomos/genética
3.
Animals (Basel) ; 13(6)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36978545

RESUMO

The neurotrophin beta-nerve growth factor (NGF), which is present in the semen of different mammals, elicits potent ovulatory and luteotrophic actions in llamas following systemic administration. Here, we determine if purified NGF given intramuscularly (IM) during the preovulatory stage affects the corpus luteum (CL), hormone production, endometrial gene expression, and pregnancy rate of dairy heifers. Holstein-Friesian heifers were estrus-synchronized using estradiol benzoate (EB) plus an intravaginal progesterone (P4) device (DIB). After eight days, the device was removed and cloprostenol was given IM; the next day (day 9), heifers received EB IM plus one of the following: (i) 1 mg of NGF (NGF D9 group), (ii) 1 mg of NGF 32 h after EB (NGF D10 group), or (iii) phosphate buffer saline (control group). To measure pregnancy rates, heifers were treated similarly, then artificially inseminated with sexed semen 48-52 h after DIB removal, then an ultrasound was conducted 30 days after insemination. The females given NGF along with EB (NGF D9) showed significantly higher luteinizing hormone (LH) concentrations, larger CL vascular areas, and higher plasma P4 concentrations than the NGF D10 and control animals. Downregulation of the P4 receptor (PGR), and upregulation of both lipoprotein lipase (LPL) and Solute Carrier Family 6 member 14 (SLC6A14) endometrial genes, were detected in NGF D9 heifers. Furthermore, these heifers had a 10% higher pregnancy rate than the control group. We conclude that the higher P4 output, in response to the early NGF administration, led to the enhanced gene expression of transcripts related to uterine receptivity that may result in enhanced pregnancy rates.

4.
Electron J Biotechnol ; 49: 22-28, Jan. 2021. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1291938

RESUMO

BACKGROUND: Vibrio species display variable and plastic fitness strategies to survive and interact with multiple hosts, including marine aquaculture species that are severely affected by pathogenic Vibrios. The culturable Vibrio sp. strain ArtGut-C1, the focus of this study, provides new evidence of such phenotypic plasticity as it accumulates polyhydroxybutyrate (PHB), a biodegradable polymer with anti-pathogen activity, particularly in the marine larviculture phase. The strain was isolated from the gut of laboratory-reared Artemia individuals, the live diet and PHB carrier used in larviculture. Its main phenotypic properties, taxonomic status and genomic properties are reported based on the whole-genome sequencing. RESULTS: Vibrio sp. ArtGut-C1 yielded 72.6% PHB of cells' dry weight at 25 C. The genomic average nucleotide identity (ANI) shows it is closely related to V. diabolicus (ANI: 88.6%). Its genome contains 5,236,997- bp with 44.8% GC content, 3,710 protein-coding sequences, 96 RNA, 9 PHB genes functionally related to PHB metabolic pathways, and several genes linked to competing and colonizing abilities. CONCLUSIONS: This culturable PHB-accumulating Vibrio strain shows high genomic and phenotypic variability. It may be used as a natural pathogen biocontrol in the marine hatchery and as a potential cell factory for PHB production.


Assuntos
Animais , Artemia/microbiologia , Vibrio/metabolismo , Poli-Hidroxialcanoatos/metabolismo , Hidroxibutiratos/metabolismo , Variação Genética , Vibrio/isolamento & purificação , Vibrio/classificação , Aquicultura , Probióticos , Crustáceos/microbiologia , Microbioma Gastrointestinal , Variação Biológica da População
5.
Front Vet Sci ; 7: 318, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32656251

RESUMO

Mesenchymal stem/stromal cells (MSCs) are increasingly explored for the treatment of degenerative and inflammatory diseases in human and veterinary medicine. One of the key characteristics of MSCs is that they modulate inflammation mainly through the secretion of soluble mediators. However, despite widespread clinical use, knowledge regarding the effector mechanisms of equine MSCs, and consequently their effectiveness in the treatment of diseases, is still unknown. The objectives of this study were to determine the mechanisms underlying inhibition of lymphocyte proliferation by equine bone marrow-derived MSCs, and to evaluate the effect of pre-conditioning of equine MSCs with different pro-inflammatory cytokines on inhibition of lymphocyte proliferation. We determined that inhibition of lymphocyte proliferation by equine MSCs depends on activity of prostaglandin-endoperoxide synthase 2 and indoleamine 2,3-dioxygenase. Additionally, pre-conditioning of MSCs with TNF-α, IFN-γ or their combination significantly increased the expression of prostaglandin-endoperoxide synthase 2, indoleamine 2,3-dioxygenase, iNOS and IL-6. This upregulation correlated with an increased inhibitory effect of MSCs on lymphocyte proliferation. In conclusion, pre-conditioning of bone marrow-derived MSC increases their inhibitory effect on lymphocyte proliferation in horses.

6.
Parasitol Res ; 119(10): 3377-3390, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32638100

RESUMO

The hypersaline lagoons located in evaporation basins or salars (salt flats) in the Atacama Desert are extreme environments harbouring a specialised biota able to survive harsh conditions for life. The knowledge of the parasitic biodiversity of these extreme habitats is still scarce despite their functional importance in regulating relevant non-economic services like habitats of waterbirds. The present study is the first report on the cestode infection of Artemia franciscana Kellogg in Salar de Atacama lagoons in northern Chile. A total of 23 parasite larvae were isolated and identified as belonging to five cestode taxa of the order Cyclophyllidea: two species of the family Hymenolepididae, i.e. Flamingolepis sp. 1 and Flamingolepis sp. 2 (adults parasitic in flamingos); two species of Dilepididae, i.e. Fuhrmannolepis averini (adults parasitic in phalaropes) and Eurycestus avoceti (adult parasitic in charadriforms birds); and one species of Progynotaeniidae, i.e. Gynandrotaenia (?) stammeri (adult parasitic in flamingos). The cysticercoids of each species are described and figured. The study represents the first geographical record of the genera Eurycestus, Gynandrotaenia and Fuhrmannolepis in South America and the first report of Gynandrotaenia and Flamingolepis in A. franciscana in its native range. This survey also contributes to the knowledge of cestodes of Phoenicopteriformes and Charadriiformes and their life cycles in the Neotropical Region. A review of cestodes recorded in brine shrimps of the genus Artemia in the world is provided. Further studies on cestode fauna of aquatic birds and their intermediate hosts in hypersaline habitats of the Neotropical Region are needed to understand their functional role in such extreme and unique ecosystems.


Assuntos
Artemia/parasitologia , Aves/parasitologia , Cestoides/crescimento & desenvolvimento , Infecções por Cestoides/veterinária , Ambientes Extremos , Animais , Aves/classificação , Cestoides/classificação , Cestoides/isolamento & purificação , Infecções por Cestoides/parasitologia , Chile , Ecossistema , Larva/classificação , Larva/crescimento & desenvolvimento , Estágios do Ciclo de Vida
7.
Vet Immunol Immunopathol ; 221: 109975, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32087476

RESUMO

BACKGROUND: Polymorphonuclear neutrophils (PMN) are the largest leukocyte population in the blood of most mammals including horses, and play an important defensive role in many infectious diseases. However, the mechanisms that increase PMN as one of the main cellular subsets in the defense against pathogens could also be involved in the pathophysiology of dysregulated inflammatory conditions. Mesenchymal stem/stromal cells (MSCs) are a heterogeneous population with a modulatory potential on the inflammatory response and are known to interact with nearly all cells of the immune system, including PMN. In this study, the in vitro modulation of equine bone marrow-derived MSCs on equine PMN phagocytosis, ROS production, and NETs generation was assessed. RESULTS: In co-culture with MSCs, unstimulated PMN produce less ROS (2.88 % ±â€¯1.43) than PMN in single culture (5.89 % ±â€¯2.63) (p = 0.016). Moreover, PMN co-cultured with MSCs remain conditioned to produce fewer ROS after PMA stimulation in comparison to PMN in single culture (p < 0.05). Additionally, it was found that incubation with MSC supernatant strongly inhibited ROS production (83 % ±â€¯6.35 less than control) without affecting phagocytosis or capacity for NETosis (p < 0.01). CONCLUSIONS: These results suggest a modulatory effect of equine BM-derived MSCs on PMN respiratory burst, without impairing other important microbicidal functions. This supports the potential use of equine MSCs in excessive or persistent inflammatory conditions in which neutrophils are the main effector cells.


Assuntos
Células da Medula Óssea/citologia , Células-Tronco Mesenquimais/citologia , Neutrófilos/imunologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Técnicas de Cocultura , Feminino , Cavalos , Masculino , Neutrófilos/metabolismo , Fagocitose , Explosão Respiratória/imunologia , Acetato de Tetradecanoilforbol/farmacologia
8.
Ir Vet J ; 72: 5, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249663

RESUMO

BACKGROUND: Tamoxifen (TAM), a selective modulator of estrogen receptors (SERMs) has been recently explored as a therapeutic option for the oral treatment of airway inflammation in the horse. The objective of this work was to establish pharmacokinetic parameters of TAM and its main metabolites in equines, as well as to determine its clinical safety in short-term treatments. RESULTS: We determined TAM and its three main metabolites (4-OH tamoxifen, endoxifen, and N-desmethyl tamoxifen) in plasma after single administration of 0.25 mg/kg in healthy adult horses (n = 12). A maximum concentration of TAM was achieved 3 h after the oral administration (4.65 pg/mL ± 1.69); 4-OH tamoxifen was the metabolite that reached the highest concentration (78 pg/mL ± 70), followed by N-desmethyl tamoxifen (0.43 pg / mL ± 0.48), and finally endoxifen (0.17 pg/mL ± 0.17). All metabolites showed peak concentration 2 h after oral administration of the drug. Oral TAM bioavailability was 13,15% ± 4,18, with a steady state volume of distribution of 7831 ± 2922 (L/kg). Elimination half-life was 15.40 ± 5.80 h, and clearance was 5876 ± 699 (mL/kg/min). Clinical safety of TAM was determined over a 7-day course of treatment (0.25 mg/kg, orally q 24 h, n = 20). No adverse effects were observed through clinical examination, blood hematology, serum biochemistry, ophthalmological and reproductive examinations. Endometrial edema observed in some mares was attributed to normal cyclic activity. CONCLUSIONS: Tamoxifen has moderate oral bioavailability and a large volume of distribution, with three main metabolites in horses. Additionally, oral TAM administration over a 7-day treatment period demonstrated to be clinically safe, without adverse effects on clinical, hematological or serum biochemical parameters. These data could contribute to the continued research into this drug's potential for the treatment of different inflammatory conditions in equine species.

9.
Molecules ; 23(5)2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29772697

RESUMO

The wide tissue distribution of the adrenergic ß3 receptor makes it a potential target for the treatment of multiple pathologies such as diabetes, obesity, depression, overactive bladder (OAB), and cancer. Currently, there is only one drug on the market, mirabegron, approved for the treatment of OAB. In the present study, we have carried out an extensive structure-activity relationship analysis of a series of 41 aryloxypropanolamine compounds based on three-dimensional quantitative structure-activity relationship (3D-QSAR) techniques. This is the first combined comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA) study in a series of selective aryloxypropanolamines displaying anti-diabetes and anti-obesity pharmacological profiles. The best CoMFA and CoMSIA models presented values of r²ncv = 0.993 and 0.984 and values of r²test = 0.865 and 0.918, respectively. The results obtained were subjected to extensive external validation (q², r², r²m, etc.) and a final series of compounds was designed and their biological activity was predicted (best pEC50 = 8.561).


Assuntos
Agonistas de Receptores Adrenérgicos beta 3/química , Fármacos Antiobesidade/química , Hipoglicemiantes/química , Propanolaminas/química , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Fármacos Antiobesidade/farmacologia , Sítios de Ligação , Desenho de Fármacos , Humanos , Hipoglicemiantes/farmacologia , Modelos Moleculares , Estrutura Molecular , Propanolaminas/farmacologia , Relação Quantitativa Estrutura-Atividade , Eletricidade Estática
10.
Front Physiol ; 3: 185, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22737126

RESUMO

The brine shrimp Artemia is a micro-crustacean, well adapted to the harsh conditions that severely hypersaline environments impose on survival and reproduction. Adaptation to these conditions has taken place at different functional levels or domains, from the individual (molecular-cellular-physiological) to the population level. Such conditions are experienced by very few equivalent macro-planktonic organisms; thus, Artemia can be considered a model animal extremophile offering a unique suite of adaptations that are the focus of this review. The most obvious is a highly efficient osmoregulation system to withstand up to 10 times the salt concentration of ordinary seawater. Under extremely critical environmental conditions, for example when seasonal lakes dry-out, Artemia takes refuge by producing a highly resistant encysted gastrula embryo (cyst) capable of severe dehydration enabling an escape from population extinction. Cysts can be viewed as gene banks that store a genetic memory of historical population conditions. Their occurrence is due to the evolved ability of females to "perceive" forthcoming unstable environmental conditions expressed by their ability to switch reproductive mode, producing either cysts (oviparity) when environmental conditions become deleterious or free-swimming nauplii (ovoviviparity) that are able to maintain the population under suitable conditions. At the population level the trend is for conspecific populations to be fragmented into locally adapted populations, whereas species are restricted to salty lakes in particular regions (regional endemism). The Artemia model depicts adaptation as a complex response to critical life conditions, integrating and refining past and present experiences at all levels of organization. Although we consider an invertebrate restricted to a unique environment, the processes to be discussed are of general biological interest. Finally, we highlight the benefits of understanding the stress response of Artemia for the well-being of human populations.

11.
Artigo em Inglês | MEDLINE | ID: mdl-19379819

RESUMO

The brine shrimp Artemia is a well known animal extremophile adapted to survive in very harsh hypersaline environments. We compared the small stress proteins artemin and p26, and the chaperone hsc70 in encysted embryos (cysts) of the New World species, A. franciscana and A. persimilis. Cysts of the former, from San Francisco Bay, USA (SFB), were used essentially as a reference for these proteins, while both species were from locations in Chile where they occur in habitats at latitudinal extremes, the Atacama desert and Patagonia. These two species are phylogenetically distant, A. persimilis being closer to the Old World species, whilst A. franciscana is considered younger and undergoing evolutionary expansion. Using western blotting we found all three stress proteins in cysts from these five populations in substantial although variable amounts. The protein profiles revealed by Coomassie staining after electrophoresis (SDS-PAGE) were similar qualitatively, in spite of marked differences in the habitats from which these populations originated, and the long time since they diverged. We interpret these findings as further evidence for the adaptive importance of these three conserved proteins in coping with the variable, but severe stresses these encysted embryos endure.


Assuntos
Artemia/classificação , Proteoma , Animais , Artemia/metabolismo , Eletroforese em Gel de Poliacrilamida , Temperatura Alta , Filogenia , Cloreto de Sódio , Especificidade da Espécie
12.
ACM arq. catarin. med ; 37(4): 53-56, set.-dez. 2008. ilus
Artigo em Português | LILACS | ID: lil-512810

RESUMO

Feto arlequim é uma variante grave da ictiose congenita, uma herança autossômica recessiva que causa alteração da queratinização da pele, que incide em cerca de 1/100.000 nascimentos e está geralmente associada a consaguinidade dos pais. Manifesta-se ao nascimento como uma pele espessada que evolui para rachaduras generalizadas, comprometendo as suas funções básicas e predispondo a infecções. Relata-se o caso de um RN do sexo feminino, cujos pais não referem nenhum grau de parentesco. A mesma foi mantida em isolamento em incubadora, mas feleceu no nono dia de vida por insuficiência respiratória restritiva.


Harlequin fetus is a variant of severe congenital ichthyosis, an autosomal recessive heredity make change in the keratinization of skin, which appear around 1/100.000 births and is usually associated with consaguineus parents. At birth it seems like a thicken skin that develops into widespread cracks, affecting its basics functions and predisposes to infections. We report the case of a female newborn, whose parents don’t mention any degree of kinship. The baby stood on isolation in incubator, but died at ninth day of life from restrictive respiratory failure.


Assuntos
Humanos , Feminino , Recém-Nascido , Consanguinidade , Ictiose Lamelar , Recém-Nascido Prematuro , Ectrópio/patologia , Ictiose Lamelar/complicações , Ictiose Lamelar/diagnóstico , Ictiose Lamelar/etiologia , Ictiose Lamelar/genética , Ictiose Lamelar/mortalidade , Ictiose Lamelar/patologia , Ictiose Lamelar/terapia , Recém-Nascido Prematuro/crescimento & desenvolvimento
13.
Saline Syst ; 2: 14, 2006 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-17132175

RESUMO

Biodiversity can be measured at different hierarchical levels, from genetic diversity within species to diversity of ecosystems, though policy-makers tend to use species richness. The 2010 goal of reducing biodiversity loss, agreed by the subscribers to the Convention on Biological Diversity, requires simple and reliable protocols to evaluate biodiversity at any level in a given ecosystem. Stakeholders, particularly policy makers, need to understand how ecosystem components interact to produce social and economic benefits on the long run, whilst scientists are expected to fulfil this demand by testing and modelling ideally simple (low diversity) ecosystems, and by monitoring key species. This work emphasizes the unique opportunity offered by inland, isolated salt lakes and the brine shrimp Artemia, an example of biodiversity contained at the intra-specific level, as simple models to understand and monitor biodiversity, as well as to assess its predicted positive association with ecosystem stability. In addition to having well identified species and strains and even clones, that allow to test reproductive effects (sexual versus asexual), Artemia benefits from the possibility to set up experimental testing at both laboratory scale and outdoor pond systems, for which a comprehensive cyst bank with sufficient amount of samples from all over the world is available.

14.
Saline Syst ; 2: 13, 2006 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-17125517

RESUMO

BACKGROUND: A preliminary biometric and ecologic database for the brine shrimp Artemia from Mexico and Chile is presented. The area abounds in small and seasonal ponds and large inland lakes, the latter mainly located in Mexico, although relatively large and isolated lakes are found in complex hydrological settings in pre-high plateau areas of Chile. This paper summarizes research efforts aimed at the localization, characterization, and evaluation of the aquaculture potential of Artemia populations in Mexico and Chile, which exhibit great habitat diversity (ponds, salterns, coastal lagoons, sea arms, coastal and inland lakes), contrasting weather conditions and different levels of isolation and human intervention. RESULTS: This study covered locations between 29 degrees north latitude (Baja California, Mexico) to 50 degrees south latitude (Puerto Natales, Chile). Biological characteristics considered are species name, reproductive mode, cyst diameter, chorion thickness, and nauplius length, whereas ecological data include pond size, pH, salinity, temperature, and water ionic composition. Artemia franciscana is the only species found in Mexico, it exists together with A. persimilis in Chile, though separated geographically. Ecological differences in habitat exist between both regions but also within countries, a pattern particularly clear with regard to water composition. Surprisingly, a Mexican (Cuatro Ciénegas, A. franciscana) and a Chilean location (Torres del Paine, A. persimilis) share habitat characteristics, at least for the period when data were collected. The discriminant analysis for cyst diameter and nauplius length shows that Artemia from only one location match in cyst diameter with those from San Francisco Bay (SFB) (Point Lobos), and one (Marquez) is far apart from SFB and all the others. The Chilean locations (Pampilla, Cejar, Cahuil, Llamara, Yape) share cyst diameter, but tend to differ from SFB. The remaining Mexican locations (Juchitan, Ohuira, Yavaros) are well separated from all the others. With regard to nauplii length, populations tend to distribute in a relatively random manner, being Marquez the location differing the most in cyst diameter from SFB. CONCLUSION: This database will contribute to the knowledge of radiation centers and serves as a baseline for further biogeographic studies, population characterization, management, and monitoring of Artemia biodiversity. Likewise, the impact of colonization and translocations for aquaculture purposes can be better assessed with a baseline for reference. Mexico and Chile exemplify the need to increase and further integrate regional information to tackle fundamental problems underlying practical utilization of Artemia.

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