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1.
Neurologia (Engl Ed) ; 39(5): 426-431, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38830721

RESUMO

INTRODUCTION: Status epilepticus is an important cause of pediatric neurological emergency. Immediate treatment is essential to prevent definitive neurological damage. Several antiepileptic drugs are available for the management of status epilepticus. METHODS: Retrospective study of patients admitted at the emergency department of a tertiary hospital for 5 years (2014-2019). We analyzed the compliance to the treatment guidelines for pediatric status epilepticus. RESULTS: One hundred and seventeen admissions were identified, 23.9% of these were febrile status epilepticus. Among the other cases, the most frequent cause was genetic (22.2%). The majority were convulsive status epilepticus (93.1%), 58.7% of which were generalized tonic-clonic seizures. Benzodiazepines were the most used first and second line drug (98.2% and 94.8%). The most frequent third drug used was diazepam (56.4%) followed by phenytoin (18.2%). An infra-therapeutic antiepileptic drug dose was given in 48.7% of cases. 49.6% presented with a prolonged status epilepticus and 6.8% needed intensive care. Incorrect sequence of drugs and infra-therapeutic doses were associated with prolonged status (p<0.001 and p<0.05) and an increased number of antiepileptic drugs used (p<0.001 and p<0.05). CONCLUSIONS: Benzodiazepines were the most frequently first and second line drugs used for status epilepticus management. Surprisingly, the most frequently third line drugs used were also benzodiazepines. These findings were partially explained by the misuse of infra-therapeutic doses of these drugs. Noncompliance with the implemented guidelines was associated with unfavorable outcomes.


Assuntos
Anticonvulsivantes , Serviço Hospitalar de Emergência , Estado Epiléptico , Humanos , Estado Epiléptico/tratamento farmacológico , Anticonvulsivantes/uso terapêutico , Estudos Retrospectivos , Feminino , Masculino , Criança , Pré-Escolar , Lactente , Benzodiazepinas/uso terapêutico , Fidelidade a Diretrizes , Adolescente , Diazepam/uso terapêutico
2.
J Endocrinol Invest ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38922369

RESUMO

PURPOSE: In patients with Primary Hyperparathyroidism (PHPT) vitamin D deficiency has been associated with more severe presentations. Our aim was to investigate the effects of Vitamin D supplementation on mineral homeostasis and related hormones in individuals with and without PHPT. METHODS: Individuals with and without PHPT (CTRL) received 14,000 IU/week of oral vitamin D3 for 12 weeks. At baseline and endpoint, blood samples were collected to measure 1,25(OH)2vitamin D (1,25(OH)2D), intact Fibroblast Growth Factor 23 (FGF23), 25OHD, Parathormone, and other biochemical markers. The 1,25(OH)2D measurement was performed using liquid chromatography and mass spectrometry (LC-MS/MS). RESULTS: 70 PHPT patients and 75 CTRL were included, and 55 PHPT and 64 CTRL completed the 12-week protocol. After the intervention, there were significant increases in the FGF23 levels (PHPT: 47.9 ± 27.1 to 76.3 ± 33.3; CTRL: 40.5 ± 13.9 to 59.8 ± 19.8 pg/mL, p < 0.001), and significant decreases in 1,25(OH)2D levels (PHPT: 94.8 ± 34.6 to 68.9 ± 25.3; CTRL: 68.7 ± 23.5 to 56.4 ± 20.7 pg/mL, p < 0.001). The reduction of 1,25(OH)2D was inversely associated with the increase of FGF23 in both the PHPT (r = -0.302, p = 0.028) and CTRL (r = -0.278, p = 0.027). No changes in plasmatic or uninary calcium concentrations were observed in both groups. CONCLUSION: The weekly administration of 14,000 IU of Vitamin D3 was safe and efficient to increase in 25OHD levels in both groups. However, a paradoxical decrease in 1,25(OH)2D levels measured by LC-MS/MS was associated with a significant increase in FGF23 levels in both groups. This phenomenon might represent a defense against hypercalcemia after vitamin D supplementation and paves the way for new studies in this regard.

3.
Mar Pollut Bull ; 205: 116607, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38896957

RESUMO

The sediment of five mangrove in Pernambuco/Brazil was investigated to find a reference site for toxicity bioassays. Sediment characteristics, metal levels, and toxic effects on the nauplius of the copepod Tisbe biminiensis were studied. The sediment was composed by terrigenous muds and siliciclastic sands with medium to high organic matter contents. The FeAs association show most of the high concentrations and positive correlation among its constituents in the south. In the north, the Ca-Sr-La association is higher and exhibits positive correlation among its components that usually found in carbonate rocks. Very intense toxic effects were observed, mainly in the south, with >70 % reductions in development. As and Hg were positively correlated with mortality and decrease in development. The sediment quality at studied mangroves prevent their use as a reference site in bioassays. These could be linked to the direct/perennial contribution of geogenic sources associated with anthropogenic environmental impacts.

4.
Aliment Pharmacol Ther ; 59(12): 1604-1615, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38690746

RESUMO

BACKGROUND: Suboptimal response to ursodeoxycholic acid occurs in 40% of primary biliary cholangitis (PBC) patients, affecting survival. Achieving a deep response (normalisation of alkaline phosphatase [ALP] and bilirubin ≤0.6 upper limit of normal) improves survival. Yet, the long-term effectiveness of second-line treatments remains uncertain. AIMS: To evaluate the long-term effectiveness of obeticholic acid (OCA) ± fibrates. Focusing on biochemical response (ALP ≤1.67 times the upper limit of normal, with a decrease of at least 15% from baseline and normal bilirubin levels), normalisation of ALP, deep response and biochemical remission (deep response plus aminotransferase normalisation). METHODS: We conducted a longitudinal, observational, multicentre study involving ursodeoxyccholic acid non-responsive PBC patients (Paris-II criteria) from Spain and Portugal who received OCA ± fibrates. RESULTS: Of 255 patients, median follow-up was 35.1 months (IQR: 20.2-53). The biochemical response in the whole cohort was 47.2%, 61.4% and 68.6% at 12, 24 and 36 months. GLOBE-PBC and 5-year UK-PBC scores improved (p < 0.001). Triple therapy (ursodeoxycholic acid plus OCA plus fibrates) had significantly higher response rates than dual therapy (p = 0.001), including ALP normalisation, deep response and biochemical remission (p < 0.001). In multivariate analysis, triple therapy remained independently associated with biochemical response (p = 0.024), alkaline phosphatase normalisation, deep response and biochemical remission (p < 0.001). Adverse effects occurred in 41.2% of cases, leading to 18.8% discontinuing OCA. Out of 55 patients with cirrhosis, 12 developed decompensation. All with baseline portal hypertension. CONCLUSION: Triple therapy was superior in achieving therapeutic goals in UDCA-nonresponsive PBC. Decompensation was linked to pre-existing portal hypertension.


Assuntos
Fosfatase Alcalina , Ácido Quenodesoxicólico , Colagogos e Coleréticos , Quimioterapia Combinada , Cirrose Hepática Biliar , Ácido Ursodesoxicólico , Humanos , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Ácido Ursodesoxicólico/uso terapêutico , Estudos Longitudinais , Cirrose Hepática Biliar/tratamento farmacológico , Idoso , Resultado do Tratamento , Fosfatase Alcalina/sangue , Colagogos e Coleréticos/uso terapêutico , Ácidos Fíbricos/uso terapêutico , Espanha , Bilirrubina/sangue , Adulto
5.
Braz J Microbiol ; 55(2): 1451-1463, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38656427

RESUMO

Antarctic temperature variations and long periods of freezing shaped the evolution of microorganisms with unique survival mechanisms. These resilient organisms exhibit several adaptations for life in extreme cold. In such ecosystems, microorganisms endure the absence of liquid water and exhibit resistance to freezing by producing water-binding molecules such as antifreeze proteins (AFP). AFPs modify the ice structure, lower the freezing point, and inhibit recrystallization. The objective of this study was to select and identify microorganisms isolated from different Antarctic ecosystems based on their resistance to temperatures below 0 °C. Furthermore, the study sought to characterize these microorganisms regarding their potential antifreeze adaptive mechanisms. Samples of soil, moss, permafrost, and marine sediment were collected on King George Island, located in the South Shetland archipelago, Antarctica. Bacteria and yeasts were isolated and subjected to freezing-resistance and ice recrystallization inhibition (IR) tests. A total of 215 microorganisms were isolated, out of which 118 were molecularly identified through molecular analysis using the 16S rRNA and ITS regions. Furthermore, our study identified 24 freezing-resistant isolates, including two yeasts and 22 bacteria. A total of 131 protein extracts were subjected to the IR test, revealing 14 isolates positive for AFP production. Finally, four isolates showed both freeze-resistance and IR activity (Arthrobacter sp. BGS04, Pseudomonas sp. BGS05, Cryobacterium sp. P64, and Acinetobacter sp. M1_25C). This study emphasizes the diversity of Antarctic microorganisms with the ability to tolerate freezing conditions. These microorganisms warrant further investigation to conduct a comprehensive analysis of their antifreeze capabilities, with the goal of exploring their potential for future biotechnological applications.


Assuntos
Proteínas Anticongelantes , Bactérias , Congelamento , Regiões Antárticas , Proteínas Anticongelantes/metabolismo , Proteínas Anticongelantes/química , Proteínas Anticongelantes/genética , Bactérias/genética , Bactérias/classificação , Bactérias/metabolismo , Bactérias/isolamento & purificação , Ilhas , Filogenia , Leveduras/genética , Leveduras/classificação , Leveduras/isolamento & purificação , Leveduras/metabolismo , RNA Ribossômico 16S/genética , Ecossistema
6.
Braz J Biol ; 84: e276323, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597517

RESUMO

Nitrogen compounds, particularly ammonium, nitrite and nitrate, are a major problem in shrimp production systems. These compounds can accumulate in the aquatic environment and reach harmful or even lethal levels. Thus, monitoring the levels of nitrogenous compounds such as ammonia and studying their effects on the animals are essential. One tool used for this purpose is acute toxicity testing based on the evaluation of LC50 values. Furthermore, tools that can help improve the performance of aquatic organisms in culture are needed. The present study aimed to evaluate the effect of salinity on the toxicity of total ammonia to postlarvae of the freshwater prawn Macrobrachium rosenbergii. For this purpose, acute toxicity testing (LC50-96h) was performed using 540 postlarvae with a mean weight of 0.13 g and a mean total length of 2.47 cm, divided into 54 experimental units of two liters each. A completely randomized design in a 3×6 factorial scheme was used, combining three salinities (0, 5, and 10 g.L-1) and six total ammonia concentrations (0, 8, 16, 32, 64, and 128 mg.L-1), with three replicates per combination. The LC50 values for M. rosenbergii postlarvae at 24, 48, 72, and 96 h and their respective confidence intervals (95%) were estimated using the trimmed Spearman-Karber method. The results showed that salinities of 5 or 10 g.L-1 did not reduce the acute toxicity of total ammonia.


Assuntos
Amônia , Palaemonidae , Animais , Amônia/toxicidade , Salinidade , Nitritos , Nitratos
7.
Phys Rev E ; 109(3-1): 034202, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38632765

RESUMO

We study the multifractal behavior of coherent states projected in the energy eigenbasis of the spin-boson Dicke Hamiltonian, a paradigmatic model describing the collective interaction between a single bosonic mode and a set of two-level systems. By examining the linear approximation and parabolic correction to the mass exponents, we find ergodic and multifractal coherent states and show that they reflect details of the structure of the classical phase space, including chaos, regularity, and features of localization. The analysis of multifractality stands as a sensitive tool to detect changes and structures in phase space, complementary to classical tools to investigate it. We also address the difficulties involved in the multifractal analyses of systems with unbounded Hilbert spaces.

8.
Ergonomics ; : 1-12, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38646862

RESUMO

Workplace incivility is considered a common workplace stressor, linked to a range of adverse impacts such as reduced wellbeing. However, there is a lack of research focused on how targets of incivility respond. The current study addresses that gap by examining responses to incivility within veterinary practice. Veterinarians and veterinary nurses (n = 132) evaluated six scenarios depicting two types of incivility (direct e.g. demeaning comments/indirect, for example, ignoring someone) across three instigators (clients, co-workers, senior colleagues), reporting their perception and appraisal of the uncivil behaviour depicted along with potential responses. Direct incivility was linked to responses such as reciprocation, exit, and support seeking, whereas indirect incivility was associated with affiliative and ignoring responses. Negative appraisal of incivility predicted a higher likelihood of exit, avoidance, support seeking and reporting responses. These findings suggest that incivility targets utilise a broad range of response options and adapt their response dependent on the situation.


This study investigated the influence of incivility type (direct/indirect) and instigator (client/co-worker/senior colleague) on response selection within veterinary practice. Participant responses were linked to incivility type and instigator status, indicating that utilisation of responses can be variable and adaptive to the situation.

9.
Rev. clín. esp. (Ed. impr.) ; 224(3): 162-166, mar. 2024.
Artigo em Espanhol | IBECS | ID: ibc-231457

RESUMO

Ante la gravedad del impacto sobre la salud del cambio climático y la degradación ambiental 32 sociedades, colegios y asociaciones de Medicina Interna de 29 países de habla hispana y lusa divulgan un documento de consenso en que llaman a la implicación de los médicos y todos los profesionales de salud en la lucha global contra las causas de estos cambios. Este compromiso requiere la cooperación de las organizaciones relacionadas con la salud, elaboración e implementación de buenas prácticas de sostenibilidad ambiental, sensibilización de los profesionales de la salud y de la población, promoción de la educación e investigación en esta área, refuerzo de la resiliencia climática y la sostenibilidad ambiental de los sistemas de salud, combatir las desigualdades y proteger a las poblaciones más vulnerables, adopción de comportamientos que protegen el medio ambiente, y defensa de la Medicina Interna como una especialidad central para habilitar al sistema de salud para responder a estos desafíos. (AU)


Facing the severity of the impact of climate change and environmental degradation on human health, 32 Internal Medicine societies, colleges, and associations of 29 Spanish and Portuguese-speaking countries issue a consensus document calling for the implication of doctors and all health professionals in the global fight against the causes of these changes. This commitment requires the cooperation of health-related organizations, elaboration and implementation of good environmental sustainability practices, greater awareness of professionals and population, promotion of education and research in this area, increasing climate resilience and environmental sustainability of health systems, combating inequalities and protecting the most vulnerable populations, adopting behaviors that protect the environment, and claiming Internal Medicine as a core specialty for empowerment of the health system to respond to these challenges. (AU)


Assuntos
Humanos , Mudança Climática , Meio Ambiente , Medicina Interna , Saúde Única , Saúde Pública
10.
Braz J Biol ; 84: e281361, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451631

RESUMO

The present study sought to evaluate the antimicrobial and anti-adherent potential of Eucalyptus radiata essential oil against food-borne strains of Escherichia coli. The study was performed using the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). In addition, the disk diffusion technique was used to evaluate the association of Eucalyptus radiata essential oil with synthetic antimicrobials. The Minimum Inhibitory Adherence Concentration (MIC) was also performed. The results revealed that E. radiata showed antimicrobial activity against the E. coli strains tested, with MIC values ranging from 500 µg/mL to 1000 µg/mL and MBC values ranging from 500 µg/mL to 1,024 µg/mL. As for the associations, it was observed that E. radiata oil exhibited a synergistic effect for some antibiotics, especially Ceftriaxone, with greater interference from the essential oil. Furthermore, it was effective in inhibiting the adherence of bacterial strains of E. coli, showing a more significant antibiofilm effect than the antibacterial agent 0.12% chlorhexidine digluconate. In summary, the essential oil of E. radiata showed antimicrobial potential against strains of E. coli of food origin, and can therefore, through in-depth studies, be used alone or in association with synthetic antimicrobials to combat infections caused by this pathogen.


Assuntos
Eucalyptus , Produtos da Carne , Óleos Voláteis , Escherichia coli , Óleos Voláteis/farmacologia , Antibacterianos/farmacologia
11.
Rev Clin Esp (Barc) ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38458942

RESUMO

Facing the severity of the impact of climate change and environmental degradation on human health, 32 Internal Medicine societies, colleges, and associations of 29 Spanish and Portuguese-speaking countries issue a consensus document in which they call for the implication of doctors and all health professionals in the global fight against the causes of these changes. This commitment requires the cooperation of health-related organizations, elaboration and implementation of good environmental sustainability practices, greater awareness of professionals and population, promotion of education and research in this area, increasing climate resilience and environmental sustainability of health systems, combating inequalities and protecting the most vulnerable populations, adopting behaviors that protect the environment, and claiming Internal Medicine as a core specialty for empowerment of the health system to respond to these challenges.

13.
Appl Neuropsychol Adult ; : 1-9, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38447166

RESUMO

INTRODUCTION: The Latin American Spanish version of the Face-Name Associative Memory Exam (LAS-FNAME) has shown promise in identifying cognitive changes in those at risk for Alzheimer's disease (AD). However, its applicability for Mild Cognitive Impairment (MCI) detection in the Latin American population remains unexplored. This study aims to analyze the psychometric properties in terms of validity and reliability and diagnostic performance of the LAS-FNAME for the detection of memory disorders in patients with amnestic MCI (aMCI). MATERIALS AND METHODS: The study included 31 participants with aMCI, diagnosed by a neurologist according to Petersen's criteria, and 19 healthy controls. Inclusion criteria for the aMCI group were to be 60 years of age or older, report cognitive complaints, have a memory test score (Craft Story 21) below a -1.5 z-score and have preserved functioning in activities of daily living. Participants completed LAS-FNAME and a comprehensive neuropsychological assessment. RESULTS: LAS-FNAME showed the ability to discriminate against healthy controls from patients with aMCI (AUC= 75) in comparison with a gold-standard memory test (AUC = 69.1). LAS-FNAME also showed evidence of concurrent and divergent validity with a standard memory test (RAVLT) (r = 0.58, p < .001) and with an attention task (Digit Span) (r = -0.37, p = .06). Finally, the reliability index was very high (α = 0.88). DISCUSSION: LAS-FNAME effectively distinguished aMCI patients from healthy controls, suggesting its potential for detecting early cognitive changes in Alzheimer's prodromal stages among Spanish speakers.

14.
Braz J Med Biol Res ; 57: e12953, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38511767

RESUMO

Bone regeneration is crucial for repairing bone tissue following various injuries. Research techniques that enable the study of metabolic changes in bone tissue under different conditions are important for understanding bone repair and remodeling. This study used bone scintigraphy to evaluate osteogenesis secondary to osteotomy in a preclinical model of New Zealand rabbits. For this purpose, we conducted a longitudinal, prospective, case-control study in which scintigraphic variables were measured in both the right forearm (case-operated) and the left forearm (control - non-operated). The study sample consisted of 10 rabbits subjected to osteotomy, followed by a 12-week postoperative evaluation period, divided into six imaging stages at 1, 2, 3, 4, 8, and 12 weeks. We observed that the operated forearm showed significantly higher external radiation than the control side, using the pinhole collimator, denoting an increase in the biodistribution and tropism of the radiopharmaceutical to the operated forearm. Among the three evaluated time points, osteoblastic activity was highest in the second week and presented a significant decline in the 8th and 12th weeks, denoting regeneration and resolution of the surgical injury; the control forearm was also influenced by the inactivity imposed by the operated forearm. This fact was notably evidenced by the reduction in the metabolic activity of osteoblasts in the left forearm. Our study suggested that bone scintigraphy was sensitive enough to semi-quantitatively differentiate the metabolic activity of osteoblasts in the operated forearm in the three temporal landmarks evaluated in the study.


Assuntos
Compostos Radiofarmacêuticos , Coelhos , Animais , Estudos de Casos e Controles , Estudos Prospectivos , Distribuição Tecidual , Cintilografia
15.
Anaesthesia ; 79(7): 759-769, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38403817

RESUMO

There is increasing interest in the use of short-acting opioids such as remifentanil to facilitate tracheal intubation. The aim of this systematic review was to determine the efficacy and safety of remifentanil for tracheal intubation compared with neuromuscular blocking drugs in adult patients. We conducted a systematic search for randomised controlled trials evaluating remifentanil for tracheal intubation. Primary outcomes included tracheal intubation conditions and adverse events. Twenty-one studies evaluating 1945 participants were included in the analysis. Use of remifentanil (1.5-4.0 µg.kg-1) showed no evidence of a difference in tracheal intubation success rate compared with neuromuscular blocking drugs (risk ratio (95%CI) 0.97 (0.94-1.01); six studies; 1232 participants; I2 28%; p = 0.16; moderate-certainty evidence). Compared with neuromuscular blocking drugs, the use of remifentanil (2.0-4.0 µg.kg-1) makes little to no difference in terms of producing excellent tracheal intubation conditions (risk ratio (95%CI) 1.16 (0.72-1.87); two studies; 121 participants; I2 31%, p = 0.54; moderate-certainty of evidence). There was no evidence of an effect between remifentanil (2.0-4.0 µg.kg-1) and neuromuscular blocking drugs for bradycardia (risk ratio (95%CI) 0.44 (0.01-13.90); two studies; 997 participants; I2 81%; p = 0.64) and hypotension (risk ratio (95%CI) 1.05 (0.44-2.49); three studies; 1071 participants; I2 92%; p = 0.92). However, the evidence for these two outcomes was judged to be of very low-certainty. We conclude that remifentanil may be used as an alternative drug for tracheal intubation in cases where neuromuscular blocking drugs are best avoided, but more studies are required to evaluate the haemodynamic adverse events of remifentanil at different doses.


Assuntos
Intubação Intratraqueal , Bloqueadores Neuromusculares , Remifentanil , Humanos , Remifentanil/administração & dosagem , Intubação Intratraqueal/métodos , Bloqueadores Neuromusculares/administração & dosagem , Adulto , Analgésicos Opioides/administração & dosagem , Piperidinas/administração & dosagem
16.
Braz. j. med. biol. res ; 57: e12953, fev.2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550149

RESUMO

Abstract Bone regeneration is crucial for repairing bone tissue following various injuries. Research techniques that enable the study of metabolic changes in bone tissue under different conditions are important for understanding bone repair and remodeling. This study used bone scintigraphy to evaluate osteogenesis secondary to osteotomy in a preclinical model of New Zealand rabbits. For this purpose, we conducted a longitudinal, prospective, case-control study in which scintigraphic variables were measured in both the right forearm (case-operated) and the left forearm (control - non-operated). The study sample consisted of 10 rabbits subjected to osteotomy, followed by a 12-week postoperative evaluation period, divided into six imaging stages at 1, 2, 3, 4, 8, and 12 weeks. We observed that the operated forearm showed significantly higher external radiation than the control side, using the pinhole collimator, denoting an increase in the biodistribution and tropism of the radiopharmaceutical to the operated forearm. Among the three evaluated time points, osteoblastic activity was highest in the second week and presented a significant decline in the 8th and 12th weeks, denoting regeneration and resolution of the surgical injury; the control forearm was also influenced by the inactivity imposed by the operated forearm. This fact was notably evidenced by the reduction in the metabolic activity of osteoblasts in the left forearm. Our study suggested that bone scintigraphy was sensitive enough to semi-quantitatively differentiate the metabolic activity of osteoblasts in the operated forearm in the three temporal landmarks evaluated in the study.

17.
Environ Pollut ; 344: 123369, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38253165

RESUMO

The interaction of multiple stressors in freshwater ecosystems may lead to adverse effects on aquatic communities and their ecological functions. Microplastics (MPs) are a class of contaminants of emerging concern that can exert both direct and indirect ecotoxicological effects. A growing number of studies have investigated MPs-attached microbial communities, but the interaction between MPs and substrate-associated biofilm (i.e., on natural river substrates, such as stones and sediments) remains poorly studied. In this work, the combined effects of polyethylene MPs (PE-MPs) with a particle size of 10-45 µm (2 mg/L) and the antimicrobial triclosan (TCS) (20 µg/L) were investigated on river biofilms through a short-term exposure experiment (72 h). To the best of authors' knowledge, this is the first time that the combined effects of MPs and chemical contaminants in substrate-associated river biofilms were assessed. Different response parameters were evaluated, including (i) exposure assessment and ii) contaminants effects at different levels: bacterial community composition, antibiotic resistance, extracellular polymeric substances (EPS), photosynthetic efficiency (Yeff), and leucine aminopeptidase activity (LAPA). Triclosan was accumulated in river biofilms (1189-1513 ng/g dw) alongside its biotransformation product methyl-triclosan (20-29 ng/g dw). Also, PE-MPs were detected on biofilms (168-292 MP/cm2), but they had no significant influence on the bioaccumulation and biotransformation of TCS. A moderate shift in bacterial community composition was driven by TCS, regardless of PE-MPs co-exposure (e.g., increased relative abundance of Sphingomonadaceae family). Additionally, Yeff and EPS content were significantly disrupted in TCS-exposed biofilms. Therefore, the most remarkable effects on river biofilms were related to the antimicrobial TCS, whereas single PE-MPs exposure did not alter any of the evaluated parameters. These results demonstrate that biofilms might act as environmental sink of MPs. Although no interaction between PE-MPs and TCS was observed, the possible indirect impact of other MPs-adsorbed contaminants on biofilms should be further assessed.


Assuntos
Anti-Infecciosos , Triclosan , Poluentes Químicos da Água , Polietileno/toxicidade , Triclosan/toxicidade , Microplásticos , Plásticos , Rios , Ecossistema , Biofilmes , Biotransformação , Poluentes Químicos da Água/toxicidade
18.
Free Radic Biol Med ; 211: 12-23, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38092272

RESUMO

BACKGROUND: The increase in blood pressure (BP) levels in the postmenopausal period can be partly explained by the decrease in nitric oxide synthases (NOS). OBJECTIVE: To investigate the acute and one-week effects of beetroot juice nitrate-rich (BRJ-NO3-rich) ingestion on cardiovascular and autonomic performance in response to submaximal aerobic exercise in postmenopausal women with systemic arterial hypertension (SAH) who are physically inactive. METHODS: Fourteen postmenopausal women with SAH [mean (SD) age: 59(4) y; BMI (kg/m2): 29.2(3.1)] completed submaximal aerobic exercise bouts after an acute and a one-week intervention with BRJ in a placebo-controlled, randomized, triple-blind, crossover design. Participants ingested either BRJ (800 mg of NO3-) or placebo acutely and drank either BRJ (400 mg of NO3-) or placebo every day for the next six days. After two and ½ hours, they performed a session of aerobic submaximal aerobic exercise, and their systolic BP (SBP) and diastolic BP (DBP), flow-mediated dilation (FMD), heart rate (HR) recovery, and HR variability were measured. RESULTS: In the post-exercise recovery period, SBP dropped significantly in the BRJ-NO3-rich group (-9.28 mmHg [95%CI: -1.68 to -16.88] ES: -0.65, p = 0.019) compared to placebo after acute ingestion. The FMD values increased after acute BRJ-NO3-rich on post-exercise (3.18 % [0.36 to 5.99] ES: 0.87, p = 0.031). After the one-week intervention, FMD values were higher in the BRJ-NO3-rich group before (4.5 % [1.62 to 7.37] ES: 1.21, p = 0.005) and post-exercise measurements (4.2 % [1.52 to 6.87] ES: 1.22, p = 0.004) vs. placebo. HRV indices with remarkable parasympathetic modulation to heart recovered faster on the BRJ-NO3-rich group than placebo group. No between-group differences were identified in values of HR post-exercise recovery in the 30s, 60s, 120s, 180s, and 300s. CONCLUSIONS: Acute and short-term BRJ-NO3-rich ingestion may enhance cardiovascular and autonomic behavior in response to aerobic exercise in postmenopausal women diagnosed with SAH. CLINICAL TRIAL REGISTRY NUMBER: https://clinicaltrials.gov/ct2/show/NCT05384340.


Assuntos
Beta vulgaris , Hipertensão , Humanos , Feminino , Pessoa de Meia-Idade , Nitratos/farmacologia , Pós-Menopausa , Suplementos Nutricionais , Sucos de Frutas e Vegetais , Hipertensão/terapia , Exercício Físico/fisiologia , Pressão Sanguínea , Ingestão de Alimentos , Método Duplo-Cego , Estudos Cross-Over
19.
Ageing Res Rev ; 93: 102141, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38030088

RESUMO

Cellular senescence is a state of terminal cell cycle arrest associated with various macromolecular changes and a hypersecretory phenotype. In the brain, senescent cells naturally accumulate during aging and at sites of age-related pathologies. Here, we discuss the recent advances in understanding the accumulation of senescent cells in brain aging and disorders. Here we highlight the phenotypical heterogeneity of different senescent brain cell types, highlighting the potential importance of subtype-specific features for physiology and pathology. We provide a comprehensive overview of various senescent cell types in naturally occurring aging and the most common neurodegenerative disorders. Finally, we critically discuss the potential of adapting senotherapeutics to improve brain health and reduce pathological progression, addressing limitations and future directions for application and development.


Assuntos
Envelhecimento , Doenças Neurodegenerativas , Humanos , Envelhecimento/fisiologia , Senescência Celular/fisiologia , Encéfalo/fisiologia , Pontos de Checagem do Ciclo Celular
20.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469243

RESUMO

Abstract In order to better understand the ossification processes in anurans our study was carried out on tadpoles and adults of Lithobates catesbeianus. In this sense, we characterized the kinetic properties of alkaline phosphatase with p-nitrophenylphosphatase (pNPP) and pyrophosphate (PPi) and evaluated the activities of tartrate-resistant acid phosphatase and acid phosphatase. The enzyme extracts were obtained from tadpoles and adult femurs, which were divided into epiphysis and diaphysis. After homogenization, the samples were submitted to differential centrifugation to obtain cell membranes and, further, to phospholipase C (PIPLC) treatment, to remove membrane-bound proteins anchored by phosphatidylinositol. The average of specific activity for pNPP hydrolysis (at pH 10.5) by alkaline phosphatase released by phosphatidylinositol-specific phospholipase C (PIPLC) from Bacillus cereus among different bone regions at different animal ages was 1,142.57 U.mg-1, while for PPi hydrolysis (at pH 8.0), it was 1,433.82 U.mg-1. Among the compounds tested for enzymatic activity, the one that influenced the most was EDTA, with approximately 67% of inhibition for pNPPase activity and 77% for PPase activity. In the case of kinetic parameters, the enzyme showed a Michaelian behavior for pNPP and PPi hydrolysis. The Km value was around 0.6mM for pNPPase activity and ranged from 0.01 to 0.11mM for PPase activity, indicating that the enzyme has a higher affinity for this substrate. The study of pNPP and PPi hydrolysis by the enzyme revealed that the optimum pH of actuation for pNPP was 10.5, while for PPi, which is considered the true substrate of alkaline phosphatase, was 8.0, close to the physiological value. The results show that regardless of the ossification type that occurs, the same enzyme or isoenzymes act on the different bone regions and different life stages of anurans. The similarity of the results of studies with other vertebrates shows that anurans can be considered excellent animal models for the study of biological calcification.


Resumo Para melhor compreender o processo de ossificação em anuros, nosso estudo foi conduzido em girinos e adultos de Lithobates catesbeianus. Nesse sentido, as propriedades cinéticas da fosfatase alcalina com p-nitrofenilfosfato (pNPP) e pirofosfato (PPi) foram caracterizadas, e as atividades enzimáticas das fosfatases ácida e ácida tartarato resistente foram avaliadas. Os extratos enzimáticos foram obtidos de fêmur de girinos e adultos, divididos em epífise e diáfise. Após a homogeneização as amostras foram submetidas à centrifugação diferencial para obter membrana celular e, em seguida, ao tratamento com fosfolipase C (PIPLC), para remover as proteínas de membrana ancoradas por fosfatidilinositol. A média da atividade específica da fosfatase alcalina, liberada pela PIPLC de Bacillus cereus, para a hidrólise de pNPP (pH 10,5) nas diferentes regiões do fêmur e idades dos animais foi de 1.142,57 U.mg-1, enquanto para a hidrólise do PPi (pH 8,0) foi de 1.433,82 U.mg-1. Entre os compostos testados para a atividade enzimática, o de maior influência foi o EDTA, inibindo aproximadamente 67% e 77% das atividades de pNPPase e PPase, respectivamente. Quanto aos parâmetros cinéticos, a enzima apresentou comportamento Michaeliano para a hidrólise dos dois substratos. O valor de Km foi de 0,6 mM para a atividade de pNPPase e variou de 0,01 a 0,11 para a atividade de PPase, indicando uma maior afinidade por esse substrato. O estudo da hidrólise de pNPP e PPi revelou que o pH ótimo aparente de atuação foi de 10,5 para o pNPP e 8,0 para o PPi, próximo ao fisiológico, sendo que esse é considerado o substrato natural da fosfatase alcalina. Os resultados demonstram que, apesar do tipo de ossificação que ocorre, a mesma enzima ou isoenzimas, atuam nos diferentes locais do osso e estágios de vida dos anuros. A similaridade dos estudos com os realizados com outros vertebrados apontam que os anuros podem ser considerados excelentes modelos animais para o estudo da calcificação biológica.

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