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1.
Mol Ecol ; 33(14): e17432, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38887831

RESUMO

Atmospheric CO2 and temperature are rising concurrently, and may have profound impacts on the transcriptional, physiological and behavioural responses of aquatic organisms. Further, spring snowmelt may cause transient increases of pCO2 in many freshwater systems. We examined the behavioural, physiological and transcriptomic responses of an ancient fish, the lake sturgeon (Acipenser fulvescens) to projected levels of warming and pCO2 during its most vulnerable period of life, the first year. Specifically, larval fish were raised in either low (16°C) or high (22°C) temperature, and/or low (1000 µatm) or high (2500 µatm) pCO2 in a crossed experimental design over approximately 8 months. Following overwintering, lake sturgeon were exposed to a transient increase in pCO2 of 10,000 µatm, simulating a spring melt based on data in freshwater systems. Transcriptional analyses revealed potential connections to otolith formation and reduced growth in fish exposed to high pCO2 and temperature in combination. Network analyses of differential gene expression revealed different biological processes among the different treatments on the edges of transcriptional networks. Na+/K+-ATPase activity increased in fish not exposed to elevated pCO2 during development, and mRNA abundance of the ß subunit was most strongly predictive of enzyme activity. Behavioural assays revealed a decrease in total activity following an acute CO2 exposure. These results demonstrate compensatory and compounding mechanisms of pCO2 and warming dependent on developmental conditions in lake sturgeon. Conserved elements of the cellular stress response across all organisms provide key information for how other freshwater organisms may respond to future climate change.


Assuntos
Dióxido de Carbono , Peixes , Lagos , Temperatura , Animais , Dióxido de Carbono/metabolismo , Peixes/genética , Transcriptoma , Mudança Climática , ATPase Trocadora de Sódio-Potássio/genética , ATPase Trocadora de Sódio-Potássio/metabolismo , Larva/genética
2.
J Exp Biol ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39091254

RESUMO

Nitrogen recycling and amino acid synthesis are two notable ways in which the gut microbiome can contribute to host metabolism, and these processes are especially important in nitrogen limited animals. Marine elasmobranchs are nitrogen limited as they require substantial amounts of this element to support urea-based osmoregulation. However, following antibiotic-induced depletion of the gut microbiome elasmobranchs are known to experience a significant decline in circulating urea and employ compensatory nitrogen conservation strategies such as reduced urea and ammonia excretion. We hypothesized that the elasmobranch gut microbiome transforms dietary and recycled nutrients into amino acids, supporting host carbon and nitrogen balance. Here, using stable isotope analyses, we found that depleting the gut microbiome of Pacific spiny dogfish (Squalus suckleyi) resulted in a significant reduction to the incorporation of supplemented dietary 15N into plasma amino acids, notably those linked to nitrogen handling and energy metabolism, but had no effect on gut amino acid transport. These results demonstrate the importance of gut microbes to host amino acid pools and the unique nitrogen handling strategy of marine elasmobranchs. More broadly, these results elucidate how the gut microbiome contributes to organismal homeostasis, which is likely a ubiquitous phenomenon across animal populations.

3.
Gen Comp Endocrinol ; 350: 114470, 2024 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-38346454

RESUMO

Chondrichthyans have a novel proglucagon-derived peptide, glucagon-like peptide (GLP)-3, in addition to GLP-1 and GLP-2 that occur in other vertebrates. Given that the GLPs are important regulators of metabolic homeostasis across vertebrates, we sought to investigate whether GLP-3 displays functional actions on metabolism within a representative chondrichthyan, the Pacific spiny dogfish Squalus suckleyi. There were no observed effects of GLP-3 perfusion (10 nM for 15 min) on the rate of glucose or oleic acid acquisition at the level of the spiral valve nor were there any measured effects on intermediary metabolism within this tissue. Despite no effects on apparent glucose transport or glycolysis in the liver, a significant alteration to ketone metabolism occurred. Firstly, ketone flux through the perfused liver switched from a net endogenous production to consumption following hormone application. Accompanying this change, significant increases in mRNA transcript abundance of putative ketone transporters and in the activity of ß-hydroxybutyrate dehydrogenase (a key enzyme regulating ketone flux in the liver) were observed. Overall, while these results show effects on hepatic metabolism, the physiological actions of GLP are distinct between this chondrichthyan and those of GLP-1 on teleost fishes. Whether this is the result of the particular metabolic dependency on ketone bodies in chondrichthyans or a differential function of a novel GLP remains to be fully elucidated.


Assuntos
Squalus acanthias , Squalus , Animais , Squalus/metabolismo , Squalus acanthias/metabolismo , Cetonas/metabolismo , Cetonas/farmacologia , Glucose/metabolismo , Fígado/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Peptídeo 1 Semelhante ao Glucagon/farmacologia
4.
Gen Comp Endocrinol ; 352: 114514, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38582175

RESUMO

Hormonal influence on hepatic function is a critical aspect of whole-body energy balance in vertebrates. Catecholamines and corticosteroids both influence hepatic energy balance via metabolite mobilization through glycogenolysis and gluconeogenesis. Elasmobranchs have a metabolic organization that appears to prioritize the mobilization of hepatic lipid as ketone bodies (e.g. 3-hydroxybutyrate [3-HB]), which adds complexity in determining the hormonal impact on hepatic energy balance in this taxon. Here, a liver perfusion was used to investigate catecholamine (epinephrine [E]) and corticosteroid (corticosterone [B] and 11-deoxycorticosterone [DOC]) effects on the regulation of hepatic glucose and 3-HB balance in the North Pacific Spiny dogfish, Squalus suckleyi. Further, hepatic enzyme activity involved in ketogenesis (3-hydroxybutyrate dehydrogenase), glycogenolysis (glycogen phosphorylase), and gluconeogenesis (phosphoenolpyruvate carboxykinase) were assessed in perfused liver tissue following hormonal application to discern effects on hepatic energy flux. mRNA transcript abundance key transporters of glucose (glut1 and glut4) and ketones (mct1 and mct2) and glucocorticoid function (gr, pepck, fkbp5, and 11ßhsd2) were also measured to investigate putative cellular components involved in hepatic responses. There were no changes in the arterial-venous difference of either metabolite in all hormone perfusions. However, perfusion with DOC increased gr transcript abundance and decreased flow rate of perfusions, suggesting a regulatory role for this corticosteroid. Phosphoenolpyruvate carboxykinase activity increased following all hormone treatments, which may suggest gluconeogenic function; E also increased 3-hydroxybutyrate dehydrogenase activity, suggesting a function in ketogenesis, and decreased pepck and fkbp5 transcript abundance, potentially showing some metabolic regulation. Overall, we demonstrate hormonal control of hepatic energy balance using liver perfusions at various levels of biological organization in an elasmobranch.


Assuntos
Squalus acanthias , Squalus , Animais , Glucose/metabolismo , Squalus/metabolismo , Squalus acanthias/metabolismo , Hidroxibutirato Desidrogenase/metabolismo , Fosfoenolpiruvato/metabolismo , Fígado/metabolismo , Ácido 3-Hidroxibutírico/farmacologia , Ácido 3-Hidroxibutírico/metabolismo , Corpos Cetônicos/metabolismo , Gluconeogênese , Hormônios/metabolismo , Corticosteroides/metabolismo
5.
Telemed J E Health ; 30(7): e2024-e2039, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38656126

RESUMO

Introduction: The COVID-19 pandemic started in Alberta in March 2020 and significantly increased telehealth service use and provision reducing the risk of virus transmission. We examined the change in the number and proportion of virtual visits by physician specialty and condition (chronic obstructive pulmonary diseases [COPD], heart failure [HF], colorectal and lung cancers), as well as associated changes in physician compensation. Methods: A population-based design was used to analyze all processed physician claims comparing the number and proportion of virtual visits and associated physician billings relative to in-person between pre- (2019/2020) and intra-pandemic (2020/2021). Physician compensations were the claim amounts paid by the health insurance. Results: Pre-pandemic (intra-), there were 8,981 (8,897) lung cancer, 9,245 (9,029) colorectal, 37,558 (36,292) HF, and 68,270 (52,308) COPD patients. Each patient had totally 2.3-4.7 (of which 0.4-0.6% were virtual) general practitioner (GP) visits and 0.9-2.3 (0.2-0.7% were virtual) specialist visits per year pre-pandemic. The average number and proportion of per-patient virtual visits to GPs and specialists grew significantly pre- to intra-pandemic by 2,138-4,567%, and 2,201-7,104%, respectively. Given the lower fees of virtual compared with in-person visits, the reduction in physician compensation associated with the increased use of virtual care was estimated at $3.85 million, with $2.44 million attributed to specialist and $1.41 million to GP. Discussion: Utilization of telehealth increased significantly, while the physician billings per patient and physician compensation declined early in the pandemic in Alberta for the four chronic diseases considered. This study forms the basis for future study in understanding the impact of virtual care, now part of the fabric of health care delivery, on quality of care and patient safety, overall health service utilization (such as diagnostic imaging and other investigations), as well as economic impacts to patients, health care systems, and society.


Assuntos
COVID-19 , Neoplasias Colorretais , Insuficiência Cardíaca , Doença Pulmonar Obstrutiva Crônica , Telemedicina , Humanos , COVID-19/epidemiologia , Alberta/epidemiologia , Doença Pulmonar Obstrutiva Crônica/terapia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Insuficiência Cardíaca/terapia , Insuficiência Cardíaca/epidemiologia , Telemedicina/estatística & dados numéricos , Telemedicina/economia , Masculino , Feminino , Neoplasias Colorretais/terapia , Neoplasias Colorretais/epidemiologia , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/epidemiologia , Pandemias , SARS-CoV-2 , Pessoa de Meia-Idade , Idoso
6.
Environ Geochem Health ; 46(9): 342, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39073664

RESUMO

Mining is responsible for the release of metallic pollutants and radioactive materials into the environment, which have the potential to disrupt ecosystems and pose significant risks to human health. Significant mining activity is concentrated in the municipality of Caetité (northeastern Brazil), where Latin America's only active uranium mine and significant iron ore deposits are located. Although previous studies have shown that the regional soil and water resources are highly contaminated by various toxic elements and that exposure to these elements is known to have adverse effects on human health, the health risks in this mining region have never been assessed. The aim of this unprecedented comprehensive investigation was to assess the health, radiological and ecological risks in this mining region, which is home to nearly 100,000 people. To achieve our goal, soil and water samples were collected in the vicinity of the mines and in the main settlements in the region. Fifteen metallic toxic elements were determined using Instrumental Neutron Activation Analysis and Inductively Coupled Plasma Optical Emission Spectrometry. The HERisk code, which follows the main methodological guidelines for risk assessment, was used to quantify human health, radiological and ecological indices. The average values of the total risk and cancer risk indices indicated that region falls into the moderate risk category (1.0 ≤ HItot < 4.0). However, 63% of the sites had high risk values, with Fe, Co and As being the metals contributing most to total and cancer risk, respectively. Near the mining areas, the potential ecological risk can be considered extreme (PERI ≥ 600). The values of the calculated radiological indices correspond to typical values ​​in natural uranium areas. However, in the communities near the mine, the dose values are slightly above the permissible limit (1 mSv y-1), so they must be continuously monitored, and risk mitigation measures must be taken.


Assuntos
Mineração , Humanos , Brasil , Medição de Risco , Monitoramento Ambiental , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Exposição Ambiental , Monitoramento de Radiação
7.
Sci Data ; 11(1): 732, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969627

RESUMO

To explore complex biological questions, it is often necessary to access various data types from public data repositories. As the volume and complexity of biological sequence data grow, public repositories face significant challenges in ensuring that the data is easily discoverable and usable by the biological research community. To address these challenges, the National Center for Biotechnology Information (NCBI) has created NCBI Datasets. This resource provides straightforward, comprehensive, and scalable access to biological sequences, annotations, and metadata for a wide range of taxa. Following the FAIR (Findable, Accessible, Interoperable, and Reusable) data management principles, NCBI Datasets offers user-friendly web interfaces, command-line tools, and documented APIs, empowering researchers to access NCBI data seamlessly. The data is delivered as packages of sequences and metadata, thus facilitating improved data retrieval, sharing, and usability in research. Moreover, this data delivery method fosters effective data attribution and promotes its further reuse. This paper outlines the current scope of data accessible through NCBI Datasets and explains various options for exploring and downloading the data.


Assuntos
Metadados , Bases de Dados Genéticas , Estados Unidos , Armazenamento e Recuperação da Informação
10.
Trib. méd. (Bogotá) ; 89(6): 282-9, jun. 1994. ilus
Artigo em Espanhol | LILACS | ID: lil-183843

RESUMO

Por la alta incidencia de cáncer gástrico, similar a la de otros estados andinos de Venezuela, se ha establecido, a partir de 1980, un Programa Piloto de Pesquisa del Cancer Gástrico en el Estado Táchira (PCG) y cuya secuencia ha consistido en planificación, motivación, radiología indirecta, segunda exploración (con fibrogastroscopia y radiología directa) histopatología, tratamiento y registro-seguimiento. Se presentan los resultados obtenidos en 429 casos avanzados y 129 precoces, observándose en los últimos años una moderada reducción en la mortalidad global.


Assuntos
Humanos , Neoplasias Gástricas/epidemiologia
11.
St. Louis; CV Mosby; 1948. 1453 p. ilus.
Monografia em Inglês | Coleciona SUS (Brasil), IMNS | ID: biblio-930695

Assuntos
Humanos , Patologia , Medicina
12.
Buenos Aires; Inter-Médica; 5 ed; 1968. ilus. (58267).
Monografia em Espanhol | BINACIS | ID: bin-58267
13.
Buenos Aires; Inter-Médica; 5 ed; 1968. ilus.
Monografia em Espanhol | BINACIS | ID: biblio-1186920
14.
Buenos Aires; López Libreros; 1963. xxiii, 700 p. ilus. (103772).
Monografia em Espanhol | BINACIS | ID: bin-103772
15.
BUENOS AIRES; LOPEZ LIBREROS; 1976. 847 p. (102329).
Monografia em Espanhol | BINACIS | ID: bin-102329
16.
BUENOS AIRES; LOPEZ LIBREROS; 2.ED; 1976. 847 p. (102327).
Monografia em Espanhol | BINACIS | ID: bin-102327
17.
BUENOS AIRES; LOPEZ LIBREROS; 2.ED; 1976. 847 p. (102326).
Monografia em Espanhol | BINACIS | ID: bin-102326
18.
Buenos Aires; Interamericana; 5. ed; 1968. 3 v p. ilus. (104658).
Monografia em Espanhol | BINACIS | ID: bin-104658
19.
BUENOS AIRES; LOPEZ LIBREROS; 2.ED; 1976. 847 p.
Monografia em Espanhol | LILACS-Express | BINACIS | ID: biblio-1209776
20.
Buenos Aires; López Libreros; 1963. xxiii, 700 p. ilus.
Monografia em Espanhol | LILACS-Express | BINACIS | ID: biblio-1210516
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