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1.
Chemosphere ; 363: 142895, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39067823

RESUMEN

Glyphosate-based herbicides (GBHs) are considered endocrine disruptors that affect the female reproductive tract of rats and ewe lambs. The present study aimed to investigate the impact of neonatal exposure to a low dose of a GBH on the ovarian follicular reserve of ewe lambs and the response to a gonadotropic stimulus with porcine FSH (pFSH). To this end, ewe lambs were orally exposed to an environmentally relevant GBH dose (1 mg/kg/day) or vehicle (Control) from postnatal day (PND) 1 to PND14, and then some received pFSH (50 mg/day) between PND41 and 43. The ovaries were dissected, and follicular types and gene expression were assessed via RT-PCR. The treatments did not affect the body weight of animals, but pFSH increased ovarian weight, not observed in GBH-exposed lambs. GBH-exposed lambs showed decreased Estrogen receptor-alpha (56%), Progesterone receptor (75%), Activin receptor II (ACVRII) (85%), and Bone morphogenetic protein 15 (BMP15) (88%) mRNA levels. Control lambs treated with pFSH exhibited downregulation of Follistatin (81%), ACVRII (77%), BMP15 (93%), and FSH receptor (FSHr) (72%). GBH-exposed lambs treated with pFSH displayed reduced ACVRII (68%), BMP15 (81%), and FSHr (50%). GBH-exposed lambs also exhibited decreased Anti-Müllerian hormone expression in primordial and antral follicles (27%) and (54%) respectively) and reduced Bone morphogenetic protein 4 (31%) expression in primordial follicles. Results suggest that GBH disrupts key follicular development molecules and interferes with pFSH action in ovarian receptors, decreasing the ovarian reserve. Future studies should explore whether this decreased ovarian reserve impairs adult ovarian function and its response to superovulation stimuli.


Asunto(s)
Glicina , Glifosato , Herbicidas , Reserva Ovárica , Ovario , Animales , Femenino , Herbicidas/toxicidad , Ovinos/fisiología , Glicina/análogos & derivados , Glicina/toxicidad , Ovario/efectos de los fármacos , Reserva Ovárica/efectos de los fármacos , Disruptores Endocrinos/toxicidad , Folículo Ovárico/efectos de los fármacos , Hormona Folículo Estimulante/sangre
2.
Glob Chang Biol ; 26(4): 2181-2202, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32077217

RESUMEN

The deep sea plays a critical role in global climate regulation through uptake and storage of heat and carbon dioxide. However, this regulating service causes warming, acidification and deoxygenation of deep waters, leading to decreased food availability at the seafloor. These changes and their projections are likely to affect productivity, biodiversity and distributions of deep-sea fauna, thereby compromising key ecosystem services. Understanding how climate change can lead to shifts in deep-sea species distributions is critically important in developing management measures. We used environmental niche modelling along with the best available species occurrence data and environmental parameters to model habitat suitability for key cold-water coral and commercially important deep-sea fish species under present-day (1951-2000) environmental conditions and to project changes under severe, high emissions future (2081-2100) climate projections (RCP8.5 scenario) for the North Atlantic Ocean. Our models projected a decrease of 28%-100% in suitable habitat for cold-water corals and a shift in suitable habitat for deep-sea fishes of 2.0°-9.9° towards higher latitudes. The largest reductions in suitable habitat were projected for the scleractinian coral Lophelia pertusa and the octocoral Paragorgia arborea, with declines of at least 79% and 99% respectively. We projected the expansion of suitable habitat by 2100 only for the fishes Helicolenus dactylopterus and Sebastes mentella (20%-30%), mostly through northern latitudinal range expansion. Our results projected limited climate refugia locations in the North Atlantic by 2100 for scleractinian corals (30%-42% of present-day suitable habitat), even smaller refugia locations for the octocorals Acanella arbuscula and Acanthogorgia armata (6%-14%), and almost no refugia for P. arborea. Our results emphasize the need to understand how anticipated climate change will affect the distribution of deep-sea species including commercially important fishes and foundation species, and highlight the importance of identifying and preserving climate refugia for a range of area-based planning and management tools.

3.
Sci Rep ; 7: 40795, 2017 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-28098211

RESUMEN

Mapping and quantifying bottom trawling fishing pressure on the seafloor is pivotal to understand its effects on deep-sea benthic habitats. Using data from the Vessel Monitoring System of crustacean trawlers along the Portuguese margin, we have identified the most exploited areas and characterized the most targeted habitats and water depths. We estimated a total trawling effort of 69596, 66766, and 63427 h y-1 for the years 2012, 2013, and 2014 respectively which, considering the total landings estimated for this gear, yield values of 20.76, 21.06, and 19.11 kg of landed fish per trawled hour. The main trawling pressure is exerted in the South and Southwest Portuguese margins, on muddy and muddy-sand bottoms between 200 and 700 m water depths, while in the North and Central-West coasts a minor effort, at shallower waters and across a wider range of habitats, is also applied. The most landed species are crustaceans such as rose shrimp and Norway lobster, although this varies importantly between the different regions of Portugal, being fish and cephalopods the main captures in the Northern ports. We discuss the consequences of trawling for the impacted communities as well as the characteristics of the commercialization of these captures in Portugal.


Asunto(s)
Crustáceos , Ecosistema , Explotaciones Pesqueras , Animales , Demografía , Geografía , Océanos y Mares , Densidad de Población , Portugal
4.
PLoS Negl Trop Dis ; 8(4): e2788, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24743161

RESUMEN

BACKGROUND: Paracoccin is a dual-function protein of the yeast Paracoccidioides brasiliensis that has lectin properties and N-acetylglucosaminidase activities. Proteomic analysis of a paracoccin preparation from P. brasiliensis revealed that the sequence matched that of the hypothetical protein encoded by PADG-3347 of isolate Pb-18, with a polypeptide sequence similar to the family 18 endochitinases. These endochitinases are multi-functional proteins, with distinct lectin and enzymatic domains. METHODOLOGY/PRINCIPAL FINDINGS: The multi-exon assembly and the largest exon of the predicted ORF (PADG-3347), was cloned and expressed in Escherichia coli cells, and the features of the recombinant proteins were compared to those of the native paracoccin. The multi-exon protein was also used for protection assays in a mouse model of paracoccidioidomycosis. CONCLUSIONS/SIGNIFICANCE: Our results showed that the recombinant protein reproduced the biological properties described for the native protein-including binding to laminin in a manner that is dependent on carbohydrate recognition-showed N-acetylglucosaminidase activity, and stimulated murine peritoneal macrophages to produce high levels of TNF-α and nitric oxide. Considering the immunomodulatory potential of glycan-binding proteins, we also investigated whether prophylactic administration of recombinant paracoccin affected the course of experimental paracoccidioidomycosis in mice. In comparison to animals injected with vehicle (controls), mice treated with recombinant paracoccin displayed lower pulmonary fungal burdens and reduced pulmonary granulomas. These protective effects were associated with augmented pulmonary levels of IL-12 and IFN-γ. We also observed that injection of paracoccin three days before challenge was the most efficient administration protocol, as the induced Th1 immunity was balanced by high levels of pulmonary IL-10, which may prevent the tissue damage caused by exacerbated inflammation. The results indicated that paracoccin is the protein encoded by PADG-3347, and we propose that this gene and homologous proteins in other P. brasiliensis strains be called paracoccin. We also concluded that recombinant paracoccin confers resistance to murine P. brasiliensis infection by exerting immunomodulatory effects.


Asunto(s)
Proteínas Fúngicas/inmunología , Vacunas Fúngicas/inmunología , Lectinas/inmunología , Paracoccidioides/inmunología , Paracoccidioidomicosis/prevención & control , Células TH1/inmunología , Acetilglucosaminidasa/metabolismo , Animales , Clonación Molecular , Escherichia coli/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Vacunas Fúngicas/administración & dosificación , Vacunas Fúngicas/genética , Expresión Génica , Lectinas/genética , Lectinas/metabolismo , Pulmón/inmunología , Pulmón/microbiología , Pulmón/patología , Macrófagos Peritoneales/efectos de los fármacos , Macrófagos Peritoneales/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Óxido Nítrico/metabolismo , Paracoccidioides/genética , Paracoccidioidomicosis/patología , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
5.
PLoS One ; 9(1): e85919, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24465788

RESUMEN

The jumbo squid Dosidicus gigas plays an important role in marine food webs both as predator and prey. We investigated the ontogenetic and spatiotemporal variability of the diet composition of jumbo squid in the northern Humboldt Current system. For that purpose we applied several statistical methods to an extensive dataset of 3,618 jumbo squid non empty stomachs collected off Peru from 2004 to 2011. A total of 55 prey taxa was identified that we aggregated into eleven groups. Our results evidenced a large variability in prey composition as already observed in other systems. However, our data do not support the hypothesis that jumbo squids select the most abundant or energetic taxon in a prey assemblage, neglecting the other available prey. Indeed, multinomial model predictions showed that stomach fullness increased with the number of prey taxa, while most stomachs with low contents contained one or two prey taxa only. Our results therefore question the common hypothesis that predators seek locally dense aggregations of monospecific prey. In addition D. gigas consumes very few anchovy Engraulis ringens in Peru, whereas a tremendous biomass of anchovy is potentially available. It seems that D. gigas cannot reach the oxygen unsaturated waters very close to the coast, where the bulk of anchovy occurs. Indeed, even if jumbo squid can forage in hypoxic deep waters during the day, surface normoxic waters are then required to recover its maintenance respiration (or energy?). Oxygen concentration could thus limit the co-occurrence of both species and then preclude predator-prey interactions. Finally we propose a conceptual model illustrating the opportunistic foraging behaviour of jumbo squid impacted by ontogenetic migration and potentially constrained by oxygen saturation in surface waters.


Asunto(s)
Decapodiformes/fisiología , Dieta , Cadena Alimentaria , Animales , Modelos Teóricos , Estado Nutricional , Océano Pacífico
6.
PLoS One ; 6(7): e22194, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21779391

RESUMEN

BACKGROUND: Cephalopods play a major role in marine ecosystems, but knowledge of their feeding ecology is limited. In particular, intra- and inter-individual variations in their use of resources has not been adequatly explored, although there is growing evidence that individual organisms can vary considerably in the way they use their habitats and resources. METHODOLOGY/PRINCIPAL FINDINGS: Using δ(13)C and δ(15)N values of serially sampled gladius (an archival tissue), we examined high resolution variations in the trophic niche of five large (>60 cm mantle length) jumbo squids (Dosidicus gigas) that were collected off the coast of Peru. We report the first evidence of large inter-individual differences in jumbo squid foraging strategies with no systematic increase of trophic level with size. Overall, gladius δ(13)C values indicated one or several migrations through the squid's lifetime (∼8-9 months), during which δ(15)N values also fluctuated (range: 1 to 5‰). One individual showed an unexpected terminal 4.6‰ δ(15)N decrease (more than one trophic level), thus indicating a shift from higher- to lower-trophic level prey at that time. The data illustrate the high diversity of prey types and foraging histories of this species at the individual level. CONCLUSIONS/SIGNIFICANCE: The isotopic signature of gladii proved to be a powerful tool to depict high resolution and ontogenic variations in individual foraging strategies of squids, thus complementing traditional information offered by stomach content analysis and stable isotopes on metabolically active tissues. The observed differences in life history strategies highlight the high degree of plasticity of the jumbo squid and its high potential to adapt to environmental changes.


Asunto(s)
Decapodiformes/fisiología , Adaptación Biológica , Animales , Isótopos de Carbono/análisis , Decapodiformes/metabolismo , Isótopos de Nitrógeno/análisis
7.
Res Vet Sci ; 91(1): 52-57, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20932541

RESUMEN

The purpose of this study was to investigate the relationship between the existence of lung lesions in pigs at slaughter and the concentration of the serum acute phase proteins (APP), haptoglobin (Hp), pig-major acute protein (Pig-MAP) and C-reactive protein (CRP). A total of 24 pig farms were selected out of a larger farm database previously screened to study risk factors associated with pleuritis and cranio-ventral pulmonary consolidation (CVPC) lesions at slaughter-aged pigs in Spain. The farms were classified as "pleuritis negative (P-) or positive (P+)" and as "CVPC negative (M-) or positive (M+)" and divided into four groups according to a 2X2 factorial design (P-M-, P-M+, P+M-, P+M+). Also at slaughter, blood from 20 randomly selected pigs from each farm was collected. Obtained serum samples were used to measure acute phase proteins. All APP concentrations were significantly higher for M+ farms than for M- ones. However, only Hp and Pig-MAP showed significantly higher concentrations for P+ farms than for P- ones. Pig-MAP was the most sensitive biomarker since it was able to clearly discriminate between P-/P+ and M-/M+ groups (p<0.001 in both cases). Hp was an excellent marker for pleuritis and good for CVPC lesions. CRP was able to discriminate for CVPC lesions but not for pleuritis. The present results indicate that Pig-MAP and, possibly Hp, may be used as potential markers to characterise and discriminate respiratory lesions in swine herds at slaughter.


Asunto(s)
Proteínas de Fase Aguda/metabolismo , Enfermedades Pulmonares/veterinaria , Pleuresia/veterinaria , Enfermedades de los Porcinos/sangre , Animales , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , Haptoglobinas/metabolismo , Enfermedades Pulmonares/sangre , Enfermedades Pulmonares/patología , Pleuresia/sangre , Pleuresia/patología , Curva ROC , España , Sus scrofa , Porcinos , Enfermedades de los Porcinos/patología
8.
PLoS One ; 6(12): e29216, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22216217

RESUMEN

The fungus Paracoccidioides brasiliensis is a human pathogen that causes paracoccidioidomycosis, the most prevalent systemic mycosis in Latin America. The cell wall of P. brasiliensis is a network of glycoproteins and polysaccharides, such as chitin, that perform several functions. N-linked glycans are involved in glycoprotein folding, intracellular transport, secretion, and protection from proteolytic degradation. Here, we report the effects of tunicamycin (TM)-mediated inhibition of N-linked glycosylation on P. brasiliensis yeast cells. The underglycosylated yeasts were smaller than their fully glycosylated counterparts and exhibited a drastic reduction of cell budding, reflecting impairment of growth and morphogenesis by TM treatment. The intracellular distribution in TM-treated yeasts of the P. brasiliensis glycoprotein paracoccin was investigated using highly specific antibodies. Paracoccin was observed to accumulate at intracellular locations, far from the yeast wall. Paracoccin derived from TM-treated yeasts retained the ability to bind to laminin despite their underglycosylation. As paracoccin has N-acetyl-ß-d-glucosaminidase (NAGase) activity and induces the production of TNF-α and nitric oxide (NO) by macrophages, we compared these properties between glycosylated and underglycosylated yeast proteins. Paracoccin demonstrated lower NAGase activity when underglycosylated, although no difference was detected between the pH and temperature optimums of the two forms. Murine macrophages stimulated with underglycosylated yeast proteins produced significantly lower levels of TNF-α and NO. Taken together, the impaired growth and morphogenesis of tunicamycin-treated yeasts and the decreased biological activities of underglycosylated fungal components suggest that N-glycans play important roles in P. brasiliensis yeast biology.


Asunto(s)
Proteínas Fúngicas/fisiología , Morfogénesis , Paracoccidioides/crecimiento & desarrollo , Acetilglucosaminidasa/metabolismo , Proteínas Fúngicas/metabolismo , Glicosilación , Lectinas/metabolismo , Macrófagos/metabolismo , Paracoccidioides/efectos de los fármacos , Paracoccidioides/enzimología , Paracoccidioides/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis , Tunicamicina/farmacología
9.
Braz. j. microbiol ; 40(3): 612-622, Sept. 2009.
Artículo en Inglés | LILACS | ID: lil-522482

RESUMEN

The filamentous fungus Aspergillus caespitosus was a good producer of intracellular and extracellular invertases under submerged (SbmF) or solid-state fermentation (SSF), using agroindustrial residues, such as wheat bran, as carbon source. The production of extracellular enzyme under SSF at 30ºC, for 72h, was enhanced using SR salt solution (1:1, w/v) to humidify the substrate. The extracellular activity under SSF using wheat bran was around 5.5-fold higher than that obtained in SbmF (Khanna medium) with the same carbon source. However, the production of enzyme with wheat bran plus oat meal was 2.2-fold higher than wheat bran isolated. The enzymatic production was affected by supplementation with nitrogen and phosphate sources. The addition of glucose in SbmF and SSF promoted the decreasing of extracellular activity, but the intracellular form obtained in SbmF was enhanced 3-5-fold. The invertase produced in SSF exhibited optimum temperature at 50ºC while the extraand intracellular enzymes produced in SbmF exhibited maximal activities at 60ºC. All enzymatic forms exhibited maximal activities at pH 4.0-6.0 and were stable up to 1 hour at 50ºC.


O fungo filamentoso Aspergillus caespitosus foi um bom produtor de invertases intracelular e extracelular em fermentação submersa (FSbm) ou em estado sólido (FES), usando resíduos agroindustriais como fonte de carbono, sendo que para ambas as condições de cultivo, a maior produtividade foi obtida empregandose farelo de trigo. A produção da forma extracelular em FES mantido a 30ºC, por 72 horas, foi aumentada usandose solução de sais SR (1:1, m/v) para umidificar o substrato, sendo aproximadamente 5,5 vezes maior se comparada a FSbm (Meio Khanna) com a mesma fonte de carbono. Entretanto, a mistura de farelo de trigo e farinha de aveia em FES levou a um aumento de 2,2 vezes na produção enzimática se comparada ao uso isolado do farelo de trigo. A produção enzimática, em ambas as condições de cultivo, foi afetada pela adição suplementar de fontes de nitrogênio e fosfato. A adição de glicose em FSbm e em FES promoveu a diminuição da enzima extracelular, mas favoreceu um acúmulo intracelular de 35 vezes maior. A temperatura ótima de atividade para as invertases produzidas em FES e em FSbm foi de 50ºC e 60ºC, respectivamente, sendo estáveis a 50ºC por mais de 60 minutos. Todas as formas enzimáticas apresentaram atividade máxima em uma faixa de pH de 4.0-6.0.

10.
Braz J Microbiol ; 40(3): 612-22, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24031406

RESUMEN

The filamentous fungus Aspergillus caespitosus was a good producer of intracellular and extracellular invertases under submerged (SbmF) or solid-state fermentation (SSF), using agroindustrial residues, such as wheat bran, as carbon source. The production of extracellular enzyme under SSF at 30°C, for 72h, was enhanced using SR salt solution (1:1, w/v) to humidify the substrate. The extracellular activity under SSF using wheat bran was around 5.5-fold higher than that obtained in SbmF (Khanna medium) with the same carbon source. However, the production of enzyme with wheat bran plus oat meal was 2.2-fold higher than wheat bran isolated. The enzymatic production was affected by supplementation with nitrogen and phosphate sources. The addition of glucose in SbmF and SSF promoted the decreasing of extracellular activity, but the intracellular form obtained in SbmF was enhanced 3-5-fold. The invertase produced in SSF exhibited optimum temperature at 50°C while the extra- and intracellular enzymes produced in SbmF exhibited maximal activities at 60°C. All enzymatic forms exhibited maximal activities at pH 4.0-6.0 and were stable up to 1 hour at 50°C.

12.
s.l; s.n; 1989. 68 p. ilus, tab, mapas.
No convencional en Español | LILACS | ID: lil-70566

RESUMEN

Analisis de la actividad del Centro de Salud n. 4 de Corrientes y propuestas de necesidades a considerar para mejorar su rendimiento, entre ellas la de educacion en salud y el cumplimiento de la ley de arancelamiento. Anexa el documento sanitario infantil de la Ley 4120/86-Corrientes


Asunto(s)
Humanos , Embarazo , Lactante , Preescolar , Masculino , Femenino , Atención Odontológica/organización & administración , Atención Primaria de Salud/tendencias , Centros Comunitarios de Salud/organización & administración , Argentina , Centros Comunitarios de Salud , Educación en Salud , Evaluación de Procesos y Resultados en Atención de Salud
13.
s.l; s.n; 1989. 68 p. ilus, Tab, mapas. (29246).
No convencional en Español | BINACIS | ID: bin-29246

RESUMEN

Analisis de la actividad del Centro de Salud n. 4 de Corrientes y propuestas de necesidades a considerar para mejorar su rendimiento, entre ellas la de educacion en salud y el cumplimiento de la ley de arancelamiento. Anexa el documento sanitario infantil de la Ley 4120/86-Corrientes


Asunto(s)
Humanos , Embarazo , Lactante , Preescolar , Masculino , Femenino , Centros Comunitarios de Salud/organización & administración , Atención Primaria de Salud/tendencias , Atención Odontológica/organización & administración , Educación en Salud , Centros Comunitarios de Salud , Evaluación de Procesos y Resultados en Atención de Salud , Argentina
14.
Corrientes; s.n; 1989. 68 p. ilus, Tab, mapa. (66366).
Monografía en Español | BINACIS | ID: bin-66366

RESUMEN

Analisis de la actividad del Centro de Salud n. 4 de Corrientes y propuestas de necesidades a considerar para mejorar su rendimiento, entre ellas la de educacion en salud y el cumplimiento de la ley de arancelamiento. Anexa el documento sanitario infantil de la Ley 4120/86-Corrientes


Asunto(s)
Humanos , Embarazo , Lactante , Preescolar , Masculino , Femenino , Centros Comunitarios de Salud/organización & administración , Atención Primaria de Salud/tendencias , Atención Odontológica/organización & administración , Educación en Salud , Centros Comunitarios de Salud
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