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1.
Sci Total Environ ; 871: 161991, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36740056

RESUMO

Sponges are unique among metazoans in their ability to use dissolved organic matter (DOM), the largest pool of organic matter in the ocean, as a major food source. The effect of variations in DOM abundance and composition on its uptake by sponges has rarely been studied. We examined, in situ, the seasonal uptake of DOM by four sponges [2 species with high microbial abundance (HMA) and 2 with low microbial abundance (LMA)] in the northwestern Mediterranean. Dissolved organic carbon (DOC) showed a strong seasonality with 3-fold higher concentrations in fall-winter (256 ± 16 µmol L-1, mean ± SE) than in spring-summer (88 ± 3 µmol L-1). Dissolved organic nitrogen (DON) showed the opposite trend, with higher summer concentrations (8.9 ± 0.4 µmol L-1) and mean concentrations of 2.5-3.4 µmol L-1 in the other seasons. DOC removal by all sponge species increased linearly with its ambient concentration, but only above a DOC removal threshold that was threefold higher in fall-winter (198 µmol L-1) than in spring-summer (74 µmol L-1). All species showed a concentration-dependent DON removal, but LMA sponges removed more DON than HMA sponges. The DOC removal rate (normalized to sponge volume) was 2-3 times higher in fall-winter, when ambient DOC levels were high, than in spring-summer. Sponges efficiently removed clusters of the fluorescent DOM (FDOM) associated with protein-rich DOM, but not those associated with humic material. The clear threshold for DOC removal and the protein-like FDOM uptake pattern suggest that the quality and quantity of DOM control its removal and transformation by marine sponges. Our results indicate that marine sponges transform the composition of the coastal DOM pool, thereby affecting its fate. It is postulated that the DOM excreted by the sponges is more recalcitrant; consequently, sponge activity enhances carbon sequestration in benthic habitats in a similar fashion to that of the oceanic 'microbial pump'.


Assuntos
Matéria Orgânica Dissolvida , Poríferos , Animais , Estações do Ano , Oceanos e Mares , Ecossistema
2.
Environ Microbiol ; 14(5): 1224-39, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22335606

RESUMO

Most marine sponges establish a persistent association with a wide array of phylogenetically and physiologically diverse microbes. To date, the role of these symbiotic microbial communities in the metabolism and nutrient cycles of the sponge-microbe consortium remains largely unknown. We identified and quantified the microbial communities associated with three common Mediterranean sponge species, Dysidea avara, Agelas oroides and Chondrosia reniformis (Demospongiae) that cohabitate coralligenous community. For each sponge we quantified the uptake and release of dissolved organic carbon (DOC) and nitrogen (DON), inorganic nitrogen and phosphate. Low microbial abundance and no evidence for DOC uptake or nitrification were found for D. avara. In contrast A. oroides and C. reniformis showed high microbial abundance (30% and 70% of their tissue occupied by microbes respectively) and both species exhibited high nitrification and high DOC and NH(4) (+) uptake. Surprisingly, these unique metabolic pathways were mediated in each sponge species by a different, and host specific, microbial community. The functional convergence of microbial consortia found in these two sympatric sponge species, suggest that these metabolic processes may be of special relevance to the success of the holobiont.


Assuntos
Bactérias/classificação , Fenômenos Fisiológicos Bacterianos , Consórcios Microbianos/fisiologia , Filogenia , Poríferos/microbiologia , Animais , Bactérias/genética , Bactérias/metabolismo , Carbono/metabolismo , Mar Mediterrâneo , Dados de Sequência Molecular , Nitrogênio/metabolismo , RNA Ribossômico 16S/genética , Simbiose
3.
Horm Metab Res ; 43(12): 884-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21960459

RESUMO

The successful introduction of rationally targeted agents into standard cancer care is a testimony of the vast knowledge base in tumor biology. However, in order to provide individually tailored therapy to patients and to identify small subsets of patients with a high likelihood to benefit from treatment, the identification of biomarkers for response or resistance to a particular therapeutic regimen is imperative. Herein, by the use of a genetically engineered mouse model of pancreatic neuroendocrine tumors, we have assessed the utility of pericyte characteristics in terms of differential marker expression to serve as surrogate markers for response or evasive resistance to anti-angiogenic therapy. We found that tumors refractory to therapy following long-term treatment with a vascular endothelial growth factor receptor-2 blocking antibody contained blood vessels with a prolific investment of pericytes expressing α-smooth muscle actin. Further analysis by simultaneous immunostaining for different pericyte markers led to the conclusion that the increased abundance of this particular subtype of blood vessels most likely occurred by co-option of vessels from the surrounding exocrine pancreas. Our findings may form the basis for retrospective analysis of pancreatic neuroendocrine tumors from patients having undergone treatment with anti-angiogenic agents in order to validate the occurrence of pericytes expressing α-smooth muscle actin as a biomarker for tumors refractory to therapy.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Tumores Neuroendócrinos/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Pericitos/metabolismo , Pericitos/patologia , Actinas/metabolismo , Inibidores da Angiogênese/farmacologia , Animais , Antígenos/metabolismo , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Camundongos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Tumores Neuroendócrinos/irrigação sanguínea , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Pericitos/efeitos dos fármacos , Proteoglicanas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Coloração e Rotulagem , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
4.
Fungal Syst Evol ; 8: 129-142, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35005577

RESUMO

Hymenobolus agaves has been reported only in Europe and Africa on the American plant Agave americana (Asparagaceae). This fungus has never been found in the native range of its host, in arid ecosystems of northern and central Mexico and Texas, USA. It has been suggested to be a pathogen that can kill its host. The fungus grows on succulent leaf bases of the plant. The morphology - black apothecia with a hymenium that disintegrates when asci mature and dark ornamented ascospores - make this species very distinctive, but it has been collected and reported only a few times since its first description. Its systematic position has been unclear, and it has been treated as incertae sedis, that is of uncertain placement, in Leotiomycetes. With recent collections and additional data on the ecology of H. agaves, we use integrative taxonomy (DNA sequences, morphology, ecology) to show its relationships is with Cenangiaceae.

5.
ISME J ; 15(7): 2001-2011, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33603147

RESUMO

Bacteriophages (phages) are ubiquitous elements in nature, but their ecology and role in animals remains little understood. Sponges represent the oldest known extant animal-microbe symbiosis and are associated with dense and diverse microbial consortia. Here we investigate the tripartite interaction between phages, bacterial symbionts, and the sponge host. We combined imaging and bioinformatics to tackle important questions on who the phage hosts are and what the replication mode and spatial distribution within the animal is. This approach led to the discovery of distinct phage-microbe infection networks in sponge versus seawater microbiomes. A new correlative in situ imaging approach ('PhageFISH-CLEM') localised phages within bacterial symbiont cells, but also within phagocytotically active sponge cells. We postulate that the phagocytosis of free virions by sponge cells modulates phage-bacteria ratios and ultimately controls infection dynamics. Prediction of phage replication strategies indicated a distinct pattern, where lysogeny dominates the sponge microbiome, likely fostered by sponge host-mediated virion clearance, while lysis dominates in seawater. Collectively, this work provides new insights into phage ecology within sponges, highlighting the importance of tripartite animal-phage-bacterium interplay in holobiont functioning. We anticipate that our imaging approach will be instrumental to further understanding of viral distribution and cellular association in animal hosts.


Assuntos
Bacteriófagos , Microbiota , Poríferos , Animais , Bacteriófagos/genética , Estilo de Vida , Microscopia , Simbiose
6.
Sci Rep ; 7(1): 5069, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28698582

RESUMO

The differential response of marine populations to climate change remains poorly understood. Here, we combine common garden thermotolerance experiments in aquaria and population genetics to disentangle the factors driving the population response to thermal stress in a temperate habitat-forming species: the octocoral Paramuricea clavata. Using eight populations separated from tens of meters to hundreds of kilometers, which were differentially impacted by recent mortality events, we identify 25 °C as a critical thermal threshold. After one week of exposure at this temperature, seven of the eight populations were affected by tissue necrosis and after 30 days of exposure at this temperature, the mean % of affected colonies increased gradually from 3 to 97%. We then demonstrate the weak relation between the observed differential phenotypic responses and the local temperature regimes experienced by each population. A significant correlation was observed between these responses and the extent of genetic drift impacting each population. Local adaptation may thus be hindered by genetic drift, which seems to be the main driver of the differential response. Accordingly, conservation measures should promote connectivity and control density erosion in order to limit the impact of genetic drift on marine populations facing climate change.


Assuntos
Antozoários/fisiologia , Mudança Climática , Ecossistema , Adaptação Fisiológica , Animais , Geografia , Especificidade da Espécie , Estresse Fisiológico , Temperatura
7.
Waste Manag ; 26(12): 1468-76, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16427267

RESUMO

New re-use applications are needed to address the relatively large quantity of waste electronic products generated in the world. Cathode-ray tubes (CRTs) from computer monitors and TV sets are a large component of such waste. The three glass components of CRTs are the funnel, panel and neck, which are produced by various manufacturers and are now collected by asset-recovery centres. In this paper, we characterize waste funnel and panel glass from dismantled cathode-ray tubes with a view to assisting the development of new re-use applications. The heavy metal (lead, barium, and strontium) content of such glass represents an acute risk to the environment. Our results of the chemical composition for different kinds of waste CRT glass including black & white and color CRTs show that CRT glass from different producers have generally similar chemical compositions. In particular, the compositions of funnel and panel black & white CRT glass are similar, but are different to those of panel and funnel color CRT glass. We also measured the following specific properties of each type of CRT glass: density, glass transition temperature, and linear coefficient of thermal expansion. It was found that the coefficients of thermal expansion of CRT glass do not vary with their composition. In contrast, the measured densities and glass transition temperatures do vary with composition. On the basis of our experimental data and data found in the literature, we outline the main properties of several waste CRT glass currently in circulation. The aim of this study was to provide the data required to determine if this kind of waste could be entirely (or partially) re-used and to aid the search for promising methods of treatment.


Assuntos
Conservação dos Recursos Naturais/métodos , Vidro/análise , Eliminação de Resíduos/métodos , Terminais de Computador , Eletrônica , Poluição Ambiental/prevenção & controle , Vidro/química , Televisão
8.
Environ Microbiol Rep ; 8(4): 536-44, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27264698

RESUMO

Ocean acidification is increasing and affects many marine organisms. However, certain sponge species can withstand low-pH conditions. This may be related to their complex association with microbes. We hypothesized that species with greater microbial diversity may develop functional redundancy that could enable the holobiont to survive even if particular microbes are lost at low-pH conditions. We evaluated the effects of acidification on the growth and associated microbes of three ubiquitous Mediterranean sponges by exposing them to the present pH level and that predicted for the year 2100. We found marked differences among the species in the acquisition of new microbes, being high in Dysidea avara, moderate in Agelas oroides and null in Chondrosia reniformis; however, we did not observe variation in the overall microbiome abundance, richness or diversity. The relative abilities to alter the microbiomes contributes to survivorship in an OA scenario as demonstrated by lowered pH severely affecting the growth of C. reniformis, halving that of A. oroides, and unaffecting D. avara. Our results indicate that functional stability of the sponge holobiont to withstand future OA is species-specific and is linked to the species' ability to use horizontal transmission to modify the associated microbiome to adapt to environmental change.


Assuntos
Microbiota , Poríferos/microbiologia , Poríferos/fisiologia , Água do Mar/química , Adaptação Fisiológica , Animais , Concentração de Íons de Hidrogênio , Oceanos e Mares , Poríferos/efeitos dos fármacos , Análise de Sobrevida
9.
Chem Commun (Camb) ; 51(45): 9284-6, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-25891539

RESUMO

The long-standing debate about the presence of P-O-B(3) linkages in glasses has been solved by high-field scalar correlation NMR. Previously suggested by dipolar NMR methods, the presence of such species has been definitively demonstrated by (11)B((31)P) J-HMQC NMR techniques. The results indicate that borophosphate networks contain P-O-B(3) bonds and thus present a higher degree of atomic homogeneity than previously thought.

10.
Theriogenology ; 84(3): 446-51, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25930731

RESUMO

Assisted reproduction technologies require ovarian stimulation to increase the number of oocytes and embryos. Currently, superstimulation is achieved by gonadotropin treatment, but the embryo yield and quality are highly variable. Commonly, commercial preparations derived from pituitary and urinary origin are used to superovulate. Hence, ovarian superstimulation protocols have usually included both FSH and LH. The appearance of recombinant gonadotropins manufactured by genetic engineering techniques has ensured high quality and batch-to-batch consistency. Moreover, this enables us to assess the importance of LH in the ovarian stimulation. The main aim of this study was to evaluate the effect of recombinant human LH supplementation (10%) on embryonic development produced by rabbit does superovulated with low or high concentration (18.75 or 37.50 IU) of recombinant human FSH (rhFSH). Females treated with rhFSH increased the ovulation rate, and it was significantly higher when the high FSH dose was supplemented with LH. The superstimulation treatment used did not significantly affect in vitro development rate until the expanded blastocyst stage. The results of this study seem to suggest that, in terms of superovulatory response, when rabbit does are treated with 37.5-IU rhFSH, the use of LH supplementation allows an increase in the number of follicles recruited and the quality of embryos, in terms of ability to develop in vitro until blastocyst, and the expression profile of OCT4, NANOG, and SOX2 genes is not affected.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Hormônio Luteinizante/farmacologia , Indução da Ovulação/veterinária , Coelhos/embriologia , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição de Octâmero/metabolismo , Indução da Ovulação/métodos , Fatores de Transcrição SOX/metabolismo
11.
Thromb Haemost ; 79(6): 1126-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9657436

RESUMO

Based on genetic variability, structural differences in the glycoprotein IIb/IIIa platelet receptor for adhesive proteins result in individual differences in the thrombogenicity of platelets. Recent studies suggest a controversial association between a genetic polymorphism of the glycoprotein IIIa gene (PlA2) and the risk of coronary artery disease. In our study, the prevalence of the PlA2 allele in a group of patients undergoing percutaneous coronary revascularization was 37%, a value significantly higher than in controls [13%, odds ratio (OR) = 3.93, 95% CI, 1.84 to 8.53] suggesting a significant association between this polymorphism and documented coronary stenosis, which is strongest among <60 years old patients (OR = 12.30, 95% CI, 2.98 to 70.93). This polymorphism represents an inherited risk factor for severe cardiovascular disease due to coronary occlusion.


Assuntos
Doença das Coronárias/genética , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/genética , Polimorfismo Genético , Idoso , Consumo de Bebidas Alcoólicas/epidemiologia , Alelos , Angioplastia Coronária com Balão , Terapia Combinada , Comorbidade , Doença das Coronárias/epidemiologia , Doença das Coronárias/cirurgia , Doença das Coronárias/terapia , Diabetes Mellitus/epidemiologia , Feminino , Fibrinogênio/análise , Frequência do Gene , Genótipo , Humanos , Hipertensão/epidemiologia , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Prevalência , Fatores de Risco , Fumar/epidemiologia , Stents
12.
Obes Surg ; 10(2): 160-6, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10782178

RESUMO

BACKGROUND: Vertical banded gastroplasty (VBG) has been found to result in significant reduction in body mass index (BMI) during the first postoperative year. We investigated the impact of some intrinsic and extrinsic factors on long-term BMI evolution in morbidly obese patients who underwent VBG, with the aim of establishing a long-term weight-loss prognosis. METHODS: 67 consecutive morbidly obese patients who underwent VBG were followed for 2 years; of these, 34 were followed 3 more years, for a total follow-up of 5 years. BMI was monitored and correlated with demographic (preoperative BMI, obese relatives, age and gender) and lifestyle variables (physical activity, habitual dietary transgression and occupational status). RESULTS: Global BMI fell from 47.5 at the time of the intervention to 32.1 when patients were examined 12 months after surgery. From the second year, an upward trend was observed, and at 5 years, mean BMI was above 35, considered in the high-risk range. Modifiable variables affecting lifestyle have shown significantly favorable effects on BMI evolution. Among intrinsic variables, BMI before surgery and obese parents also affect long-term evolution. CONCLUSION: Different variables should be considered in order to establish a long-term weight-loss prognosis for each patient, thus making it possible to act more specifically on modifiable variables.


Assuntos
Índice de Massa Corporal , Gastroplastia/métodos , Obesidade Mórbida/cirurgia , Adulto , Feminino , Seguimentos , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Aumento de Peso , Redução de Peso/fisiologia
13.
Rev Esp Cardiol ; 50(1): 26-30, 1997 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-9053943

RESUMO

Throughout the last few decades, different factors have been related to coronary stenosis which is clinically evidenced by coronary heart disease, the leading cause of death in developed countries. Different experimental models have contributed towards defining some of these factors, and to an understanding of the physiopathology of the atherosclerotic lesion. The genetic basis related to individual responses to the same event is currently being established. As endothelial injury reparative mechanisms are fundamental in atherosclerosis pathogeny, patients who experiment restenosis after undergoing revascularization procedures are useful human models in the study of these processes. We review from the literature the genetic factors related to thrombus formation, which may be associated with restenosis after percutaneous transluminal coronary angioplasty, in order to define the most suitable anticoagulant therapy for each patient. We refer to the recently characterized gene for the platelet receptors and its relationship with fibrinogenous, factor Xa, PAI-I, and the involvement of apolipoprotein (a) in the coagulation process.


Assuntos
Angioplastia Coronária com Balão , Coagulação Sanguínea , Isquemia Miocárdica/genética , Suscetibilidade a Doenças , Fator Xa/fisiologia , Fibrinogênio/fisiologia , Humanos , Lipoproteína(a)/fisiologia , Isquemia Miocárdica/sangue , Inibidor 1 de Ativador de Plasminogênio/fisiologia , Agregação Plaquetária , Recidiva
14.
An Otorrinolaringol Ibero Am ; 28(1): 51-8, 2001.
Artigo em Espanhol | MEDLINE | ID: mdl-11265519

RESUMO

In recent years criteria for the cochlear implant candidacy have been widened to childhood, therefore we are compelled to look for the earlier possible diagnosis of deafness. With this aim the AA. have reviewed the diagnostic process of hearing loss made during the last two decades and, consequently, be aware of the problems and planning solutions to avoid unnecesary delays in the treatment.


Assuntos
Perda Auditiva Bilateral/diagnóstico , Perda Auditiva Neurossensorial/diagnóstico , Programas de Rastreamento , Pré-Escolar , Perda Auditiva Bilateral/congênito , Perda Auditiva Neurossensorial/congênito , Humanos , Lactente
15.
Rev Enferm ; 20(231): 59-63, 1997 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-9451237

RESUMO

OBJECTIVE: To evaluate the performance of the hydrofiber dressing in the treatment of leg ulcers. METHODS: Multicenter, open, non-comparative study of 23 patients with the mean age of 69.6 years. The mean duration of actual ulcer was 2.6 years. RESULTS: Twelve (55%) patients had marketed improvement in overall change in the condition on the wound and 5 (23%) patients had mild improvement. The majority of dressing changes were pain-free (63%). The dressing changes, application and removal, were easy 171 (99%) and 149 (87%). The mean dressing wear time was 2.4 days. The mean ulcer area at the start of the study was 2.730 mm2 and the final dressing change was 1.963 mm2. The median percentage reduction was 36%. CONCLUSION: The use of the non-occlusive hydrofiber dressing is suitable for the treatment of exudating leg ulcers.


Assuntos
Bandagens/normas , Úlcera da Perna/enfermagem , Idoso , Feminino , Humanos , Masculino , Estudos Prospectivos , Fatores de Tempo , Cicatrização
19.
Phys Rev Lett ; 103(11): 115502, 2009 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-19792382

RESUMO

We demonstrate that while the metastable face-centered cubic (fcc) phase of Ge2Sb2Te5 becomes amorphous under hydrostatic compression at about 15 GPa, the stable trigonal phase remains crystalline. Upon higher compression, a body-centered cubic phase is obtained in both cases around 30 GPa. Upon decompression, the amorphous phase is retained for the starting fcc phase while the initial structure is recovered for the starting trigonal phase. We argue that the presence of vacancies and associated subsequent large atomic displacements lead to nanoscale phase separation and loss of initial structure memory in the fcc staring phase of Ge2Sb2Te5.

20.
Phys Rev Lett ; 97(3): 035701, 2006 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-16907512

RESUMO

We demonstrate that , the material of choice in phase-change optical recording (such as DVD-RAM), can be rendered amorphous by the application of hydrostatic pressure. It is argued that this structural change is due to a very strong second-nearest-neighbor Te-Te interaction that determines the long-range order in the metastable cubic phase of and also to the presence of vacancies. This newly discovered phenomenon suggests that pressure is an important factor for the formation of the amorphous phase which opens new insight into the mechanism of phase-change optical recording.

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