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1.
J Am Heart Assoc ; : e035264, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958130

RESUMO

BACKGROUND: 123Iodine-meta-iodobenzylguanidine scintigraphy is useful for assessing cardiac autonomic dysfunction and predict outcomes in heart failure (HF). The relationship of cardiac sympathetic function with myocardial remodeling and diffuse fibrosis remains largely unknown. We aimed to evaluate the cardiac sympathetic function of patients with HF and its relation with myocardial remodeling and exercise capacity. METHODS AND RESULTS: Prospectively enrolled patients with HF (New York Heart Association class II-III) were stratified into HF with preserved left ventricular ejection fraction [LVEF] ≥45%) and reduced LVEF. Ventricular morphology/function and myocardial extracellular volume (ECV) fraction were quantified by cardiovascular magnetic resonance, global longitudinal strain by echocardiography, cardiac sympathetic function by heart-to-mediastinum ratio from 123iodine-meta-iodobenzylguanidine scintigraphy. All participants underwent cardiopulmonary exercise testing. The cohort included 33 patients with HF with preserved LVEF (LVEF, 60±10%; NT-proBNP [N-terminal pro-B-type natriuretic peptide], 248 [interquartile range, 79-574] pg/dL), 28 with HF with reduced LVEF (LVEF, 30±9%; NT-proBNP, 743 [interquartile range, 250-2054] pg/dL) and 20 controls (LVEF, 65±5%; NT-proBNP, 40 [interquartile range, 19-50] pg/dL). Delayed (4 hours) 123iodine-meta-iodobenzylguanidine heart-to-mediastinum ratio was lower in HF with preserved LVEF (1.59±0.25) and HF with reduced LVEF (1.45±0.16) versus controls (1.92±0.24; P<0.001), and correlated negatively with diffuse fibrosis assessed by ECV (R=-0.34, P<0.01). ECV in segments without LGE was increased in HF with preserved ejection fraction (0.32±0.05%) and HF with reduced left ventricular ejection fraction (0.31±0.04%) versus controls (0.28±0.04, P<0.05) and was associated with the age- and sex-adjusted maximum oxygen consumption (peak oxygen consumption); (R=-0.41, P<0.01). Preliminary analysis indicates that cardiac sympathetic function might potentially act as a mediator in the association between ECV and NT-proBNP levels. CONCLUSIONS: Abnormally low cardiac sympathetic function in patients with HF with reduced and preserved LVEF is associated with extracellular volume expansion and decreased cardiopulmonary functional capacity.

2.
JACC Adv ; 3(4): 100880, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38939675

RESUMO

Background: Managing patients with atrial fibrillation (AF) and worsening renal function (WRF) remains a clinical challenge due to the need of dose adjustment of non-vitamin K antagonist oral anticoagulants. Objectives: To determine the incidence of WRF in patients with AF treated with edoxaban, the association of WRF with clinical outcomes, and predictors of WRF and clinical outcomes in these patients. Methods: This is a subanalysis of the Edoxaban Treatment in routiNe clinical prActice for patients with non-valvular Atrial Fibrillation in Europe study (NCT02944019), an observational study of edoxaban-treated patients with AF. WRF was defined as a ≥25% reduction in creatinine clearance between baseline and 2 years. Results: Of the 9,054 patients included (69% of the total 13,133 enrolled), most did not experience WRF (90.3%) during the first 2 years of follow-up. WRF occurred in 9.7% of patients. Patients with WRF had significantly higher rates of all-cause death (3.88%/y vs 1.88%/y; P < 0.0001), cardiovascular death (2.09%/y vs 0.92%/y; P < 0.0001), and major bleeding (1.51%/y vs 0.98%/y; P = 0.0463) compared with those without WRF. Rates of intracranial hemorrhage (0.18%/y vs 0.18%/y) and of any stroke/systemic embolic events were low (0.90%/y vs 0.69%/y; P = 0.3161) in both subgroups. The strongest predictors of WRF were a high CHA2DS2-VASc score, high baseline creatinine clearance, low body weight, and older age. Most predictors of WRF were also predictors of clinical outcomes. Conclusions: WRF occurred in approximately 10% of edoxaban-treated AF patients. Rates of death and major bleeding were significantly higher in patients with WRF than without. Stroke events were low in both subgroups.

3.
Acta Trop ; 256: 107267, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38777256

RESUMO

Chagas disease (CD), caused by the protozoan Trypanosoma cruzi (T. cruzi), is a neglected disease endemic to some Latin American countries, including Brazil. Soon after infection, individuals develop an acute phase, which in most cases is asymptomatic and may go undetected. However, when CD is detected early, notification in the Notifiable Diseases Information System (SINAN), is mandatory. This study aimed to evaluate the information registered in the SINAN database and to determine the epidemiological profile of acute CD in Northeast Brazil, an endemic region, from 2001 to 2021. According to this survey, 1,444 cases of acute CD were reported in the Northeastern region of Brazil during this period. During the first six years, referred to as period 1, 90.24% of the notifications were registered, while the number of notifications significantly decreased in the subsequent years, referred to as period 2. Most individuals diagnosed with acute CD were Afro-Brazilian adults. All known routes of infection by the parasite were reported. Vector-borne transmission was predominant during period 1 (73.29%) and oral transmission during period 2 (58.87%). All nine states in Northeast Brazil reported cases in both periods. A higher incidence of disease was reported in Rio Grande do Norte (RN) during period 1, and in Maranhão (MA) during period 2. Our results show that CD remains a significant public health challenge.


Assuntos
Doença de Chagas , Doença de Chagas/epidemiologia , Doença de Chagas/transmissão , Brasil/epidemiologia , Humanos , Masculino , Adulto , Feminino , Pessoa de Meia-Idade , Adolescente , Criança , Pré-Escolar , Adulto Jovem , Notificação de Doenças/estatística & dados numéricos , Lactente , Idoso , Incidência , Trypanosoma cruzi , Doença Aguda/epidemiologia , Recém-Nascido , Idoso de 80 Anos ou mais
4.
BMC Ecol Evol ; 24(1): 72, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816840

RESUMO

Ctenoluciidae is a Neotropical freshwater fish family composed of two genera, Ctenolucius (C. beani and C. hujeta) and Boulengerella (B. cuvieri, B. lateristriga, B. lucius, B. maculata, and B. xyrekes), which present diploid number conservation of 36 chromosomes and a strong association of telomeric sequences with ribosomal DNAs. In the present study, we performed chromosomal mapping of microsatellites and transposable elements (TEs) in Boulengerella species and Ctenolucius hujeta. We aim to understand how those sequences are distributed in these organisms' genomes and their influence on the chromosomal evolution of the group. Our results indicate that repetitive sequences may had an active role in the karyotypic diversification of this family, especially in the formation of chromosomal hotspots that are traceable in the diversification processes of Ctenoluciidae karyotypes. We demonstrate that (GATA)n sequences also accumulate in the secondary constriction formed by the 18 S rDNA site, which shows consistent size heteromorphism between males and females in all Boulengerella species, suggesting an initial process of sex chromosome differentiation.


Assuntos
Caraciformes , Mapeamento Cromossômico , Sequências Repetitivas de Ácido Nucleico , Retroelementos , Animais , Caraciformes/genética , Masculino , Feminino , Retroelementos/genética , Sequências Repetitivas de Ácido Nucleico/genética , Evolução Molecular , Repetições de Microssatélites/genética , Cariótipo , Cromossomos/genética
5.
ACS Omega ; 9(20): 22296-22304, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38799375

RESUMO

Halide perovskites have attracted much attention for energy conversion. However, efficient charge carrier generation, separation, and mobility remain the most important issues limiting the higher efficiency of solar cells. An efficient interfacial charge transfer process associated with exciton dynamics between all-inorganic CsPbBr3 nanocrystals and organic electron acceptors has been suggested. We observed a strong PL quenching of 78% in thin films when silane-functionalized naphthalenediimides (SNDI), used as electron-acceptors, are anchored on CsPbBr3 nanocrystals. Optical and structural characterizations confirm the charge transfer process without QDs degradation. The issue of whether these transferred charges are indeed available for utilization in solar cells remains uncertain. Our results reveal that the CsPbBr3 nanocrystals capped with these electron-acceptor SNDI molecules show a drastic increase in the electrical resistance and the absence of a photoconductivity effect. The results suggest charge transfer followed by strong localization of the charge carriers, preventing their extraction toward the electrodes of solar cell devices. We hope that this crucial aspect to attract attention and unveil a potential mechanism for charge delocalization, which could, in turn, lead to a groundbreaking enhancement in solar cell efficiency.

6.
Einstein (Sao Paulo) ; 22: eRC0522, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597464

RESUMO

Adenosine is an antiarrhythmic drug that slows conduction through the atrioventricular node and acts as a coronary blood vessel dilator. This case report highlights two unusual life-threatening events following the use of adenosine to revert supraventricular tachycardia in a structurally normal heart: non-sustained polymorphic ventricular tachycardia and myocardial infarction. A 46-year-old woman presented to the emergency department with a two-hour history of palpitations and was diagnosed with supraventricular tachycardia. Vagal maneuvers were ineffective, and after intravenous adenosine administration, the patient presented with chest pain and hypotension. The rhythm degenerated into non-sustained polymorphic ventricular tachycardia and spontaneously reverted to sinus rhythm with ST elevation in lead aVR and ST depression in the inferior and anterolateral leads. The patient spontaneously recovered within a few minutes. Despite successful arrhythmia reversal, the patient was admitted to the intensive care unit because of an infarction without obstructive atherosclerosis. This report aims to alert emergency physicians about the potential complications associated with supraventricular tachycardia and its reversal with adenosine.


Assuntos
Infarto do Miocárdio , Taquicardia Supraventricular , Torsades de Pointes , Feminino , Humanos , Pessoa de Meia-Idade , Adenosina/efeitos adversos , Torsades de Pointes/tratamento farmacológico , Eletrocardiografia , Taquicardia Supraventricular/tratamento farmacológico , Arritmias Cardíacas , Infarto do Miocárdio/complicações , Infarto do Miocárdio/tratamento farmacológico
7.
Luminescence ; 39(4): e4732, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38556715

RESUMO

In the present work, glass samples in the (100 - x)B2O3-xLi2O binary system, with x varying from 30 to 50 mol%, were prepared using the conventional melting and moulding method, with the main objective of evaluating the thermoluminescence response when exposing these materials to ultraviolet (UV) radiation. Complementary analysis based on density, optical absorption on the UV-visible region (UV-vis absorbance), Fourier transform infrared spectroscopy on the medium region, X-ray diffraction, and differential thermal analysis measurements were performed. Thermoluminescence measurements of vitreous samples showed glow curves with at least one peak with a maximum temperature of ~170°C after exposure to UV radiation in the temperature range 50-250°C. Samples were also exposed to beta radiation in the temperature range 25-275°C, also showing single peaks with a maximum temperature of ~150°C.


Assuntos
Partículas beta , Boratos , Boratos/química , Compostos de Lítio , Temperatura
9.
Biomed Pharmacother ; 174: 116554, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38636401

RESUMO

We aimed to investigate the effectiveness of physical training as a protective strategy to mitigate alveolar bone damage and blood antioxidant defense caused by ethanol (EtOH) consumption in a binge-drinking pattern. Male Wistar rats aged approximately 90 days were divided into four groups: control, training, EtOH, and training + EtOH. The physical training protocol was conducted on a treadmill for four consecutive weeks, while the animals in the EtOH group were administered EtOH via orogastric gavage for three consecutive days each week, following the binge drink pattern. After the training period, blood and mandibles were collected for plasma oxidative biochemistry analysis, and the alveolar bone was subjected to physicochemical composition analysis, tissue evaluation, and microtomography evaluation. Our results showed that EtOH induced oxidative stress and physical exercise promoted the recovery of antioxidant action. Physical training minimized the damage to the mineral/matrix composition of the alveolar bone due to EtOH consumption and increased the density of osteocytes in the trained group treated with EtOH than in those exposed only to EtOH. Furthermore, physical training reduced damage to the alveolar bone caused by EtOH consumption. Our findings suggest that physical training can serve as an effective strategy to reduce systemic enzymatic oxidative response damage and alleviate alveolar bone damage resulting from alcohol consumption. Further investigations are warranted to elucidate the underlying mechanisms and explore, in addition to physical training, the potential effects of other activities with varying intensities on managing alcohol-induced bone damage.


Assuntos
Antioxidantes , Consumo Excessivo de Bebidas Alcoólicas , Etanol , Estresse Oxidativo , Condicionamento Físico Animal , Ratos Wistar , Animais , Masculino , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Condicionamento Físico Animal/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Consumo Excessivo de Bebidas Alcoólicas/sangue , Etanol/toxicidade , Ratos
10.
Environ Pollut ; 347: 123791, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490529

RESUMO

Evidence of microplastic (MP) pollution in Antarctic terrestrial environments reinforces concerns about its potential impacts on soil, which plays a major role in ecological processes at ice-free areas. We investigated the effects of two common MP types on soil physicochemical properties and microbial responses of a marine terrace from Fildes Peninsula (King George Island, Antarctica). Soils were treated with polyethylene (PE) fragments and polyacrylonitrile (PAN) fibers at environmentally relevant doses (from 0.001% to 1% w w-1), in addition to a control treatment (0% w w-1), for 22 days in a pot incubation experiment under natural field conditions. The short-term impacts of MPs on soil physical, chemical and microbial attributes seem interrelated and were affected by both MP dose and type. The highest PAN fiber dose (0.1%) increased macro and total porosity, but decreased soil bulk density compared to control, whereas PE fragments treatments did not affect soil porosity. Soil respiration increased with increasing doses of PAN fibers reflecting impacts on physical properties. Both types of MPs increased microbial activity (fluorescein diacetate hydrolysis), decreased the cation exchange capacity but, especially PE fragments, increased Na+ saturation. The highest dose of PAN fibers and PE fragments increased total nitrogen and total organic carbon, respectively, and both decreased the soil pH. We discussed potential causes for our findings in this initial assessment and addressed the need for further research considering the complexity of environmental factors to better understand the cumulative impacts of MP pollution in Antarctic soil environments.


Assuntos
Resinas Acrílicas , Microplásticos , Plásticos , Regiões Antárticas , Polietileno , Solo/química
11.
Food Res Int ; 182: 114153, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38519181

RESUMO

Previous research has demonstrated that Prebiotics can influence the composition of the gut microbiota, consequently impacting mood regulation. This study aimed to assess the effects of Prebiotics, specifically Fructooligosaccharides (FOS) and Galactooligosaccharides (GOS) on neuroinflammation, depression, and anxiety-like behavior in a mouse model fed a high-fat diet (HFD). Initially, mice were divided into two groups: a control group on a standard diet (n = 15) and a group on an HFD for 18 weeks (n = 45). By the 13th week, the HFD group was further divided into experimental groups: Control (n = 15), HFD (n = 15), HFD receiving Prebiotics (n = 15), and HFD receiving Fluoxetine (n = 15). From the 13th week onward, the HFD + Prebiotics group received both the high-fat diet and a combination of FOS and GOS, while the HFD + Fluoxetine group received Fluoxetine in their drinking water. In the 18th week, all mice underwent tests to evaluate behavior, including the Tail Suspension Test (TST), Forced Swimming Test (FST), Sucrose Preference Test (SPT), and the Plus Maze Test (PMT), after which they were euthanized. Mice on the HFD exhibited increased body weight, abdominal size, blood glucose, triglyceride levels, cholesterol, insulin, HOMA index, and higher serum IL-1ß. These obese mice also displayed an increased number of microglia and astrocytes, activation of the TLR4 pathway, and elevated levels of neuroinflammatory markers like TNF-α, IL-1ß, and COX-2. Moreover, obese mice showed increased activation of the IDO pathway and decreased levels of NMDA receptors. Additionally, markers of neurogenesis and synaptic plasticity, such as PSD, SAP 102, CREB-p, and BDNF, were lower. Treatment with FOS and GOS reversed symptoms of depression and anxiety in mice subjected to HD. This improvement in behavior resulted from a reduction in dysbiosis with an increase in acetate-producing bacteria (B. acidifaciens and B. dorei) and intestinal permeability, leading to a decrease in chronic peripheral and central inflammation. Furthermore, the modulation of the gut-brain axis by FOS and GOS promoted elevated acetate and GPR43 levels in the brain and a reduction in the levels of pro-inflammatory cytokines, positively impacting signaling pathways of neuronal proliferation and survival in the hippocampus and prefrontal cortex.


Assuntos
Depressão , Prebióticos , Camundongos , Animais , Eixo Encéfalo-Intestino , Obesidade/metabolismo , Dieta Hiperlipídica/efeitos adversos , Fluoxetina/farmacologia , Camundongos Obesos , Ansiedade , Acetatos
12.
Heliyon ; 10(6): e27206, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38515724

RESUMO

Background and aims: Cardiomyocyte hypertrophy and interstitial fibrosis are key components of myocardial remodeling in Heart Failure (HF) with preserved (HFpEF) or reduced ejection fraction (HFrEF). MicroRNAs (miRNAs) are non-coding, evolutionarily conserved RNA molecules that may offer novel insights into myocardial remodeling. This study aimed to characterize miRNA expression in HFpEF (LVEF ≥ 45%) and HFrEF (LVEF < 45%) and its association with myocardial remodeling. Methods: Prospectively enrolled symptomatic HF patients (HFpEF:n = 36; HFrEF:n = 31) and controls (n = 23) underwent cardiac magnetic resonance imaging with T1-mapping and circulating miRNA expression (OpenArray system). Results: 13 of 188 miRNAs were differentially expressed between HF groups (11 downregulated in HFpEF). Myocardial extracellular volume (ECV) was increased in both HF groups (HFpEF 30 ± 5%; HFrEF 30 ± 3%; controls 26 ± 2%, p < 0.001). miR-128a-3p, linked to cardiac hypertrophy, fibrosis, and dysfunction, correlated positively with ECV in HFpEF (r = 0.60, p = 0.01) and negatively in HFrEF (r = -0.51, p = 0.04). miR-423-5p overexpression, previously associated HF mortality, was inversely associated with LVEF (r = - 0.29, p = 0.04) and intracellular water lifetime (τic) (r = -0.45, p < 0.05) in both HF groups, and with NT-proBNP in HFpEF (r = -0.63, p < 0.01). Conclusions: miRNA expression profiles differed between HF phenotypes. The differential expression and association of miR-128a-3p with ECV may reflect the distinct vascular, interstitial, and cellular etiologies of HF phenotypes.

13.
Orthod Craniofac Res ; 27(4): 544-551, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38321815

RESUMO

OBJECTIVE: To compare the anterior crowding correction after sequential use of the first 5 aligners between two aligner exchange protocols (7 and 14 days) in mature adult patients. MATERIALS AND METHODS: Thirty-six patients over 35 years who received orthodontic treatment with Invisalign® were randomly allocated to two different aligner replacement sequence protocols: Group 1: exchange every 7 days (n = 18); and Group 2: exchange every 14 days (n = 18). All patients were scanned with iTero Element 5D® (Align Technology) in two treatment times: at pre-treatment (T1) and after using the first five aligners (T2). Little's Irregularity Index (LII) and arch widths were evaluated with OrthoCAD software. Intra and intergroup comparisons were performed with the dependent and independent t-tests. The results were considered significant for P < .05. RESULTS: Thirty-five patients completed the study. Both groups' maxillary and mandibular Irregularity Indexesi were significantly lower at T2. There was no significant difference in inter-canine, inter-premolar, and intermolar distances. G2 (14 days) presented a greater decrease in mandibular irregularity than G1 (7 days). CONCLUSION: Both exchange protocols (7 and 14 days) effectively correct anterior crowding in the initial phase of orthodontic treatment with aligners in mature adult patients. However, the 14-day exchange protocol provided a greater correction in mandibular anterior crowding in the evaluated period than the 7-day exchange protocol.


Assuntos
Má Oclusão , Técnicas de Movimentação Dentária , Humanos , Adulto , Masculino , Feminino , Má Oclusão/terapia , Técnicas de Movimentação Dentária/instrumentação , Técnicas de Movimentação Dentária/métodos , Desenho de Aparelho Ortodôntico , Resultado do Tratamento , Fatores de Tempo , Aparelhos Ortodônticos Removíveis , Pessoa de Meia-Idade
14.
ACS Appl Mater Interfaces ; 16(3): 4261-4270, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38217498

RESUMO

Layered lead halide perovskites have attracted much attention as promising materials for a new generation of optoelectronic devices. To make progress in applications, a full understanding of the basic properties is essential. Here, we study 2D-layered (BA)2PbX4 by using different halide anions (X = I, Br, and Cl) along with quantum confinement. The obtained cell parameter evolution, supported by experimental measurements and theoretical calculations, indicates strong lattice distortions of the metal halide octahedra, breaking the local inversion symmetry in (BA)2PbCl4, which strongly correlates with a pronounced Rashba spin-splitting effect. Optical measurements reveal strong photoluminescence quenching and a drastic reduction in the PL quantum yield in this larger band gap compound. We suggest that these optical results are closely related to the appearance of the Rashba effect due to the existence of a local electric dipole. The results obtained in ab initio calculations showed that the (BA)2PbCl4 possesses electrical polarization of 0.13 µC/cm2 and spin-splitting energy of about 40 meV. Our work establishes that local octahedra distortions induce Rashba spin splitting, which explains why obtaining UV-emitting materials with high PLQY is a big challenge.

15.
Clin Res Cardiol ; 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38294497

RESUMO

BACKGROUND: Patients with atrial fibrillation (AF) and a recent (≤ 90 days) percutaneous coronary intervention (PCI) undergoing transcatheter aortic valve implantation (TAVI) are at high bleeding risk due to the addition of oral antiplatelet (OAP) agents on top of oral anticoagulants. Data on outcomes of these patients are needed to optimize antithrombotic treatment. METHODS: This analysis compared annualized clinical event rates in patients with and without a recent PCI enrolled in ENVISAGE-TAVI AF, a prospective, randomized, open-label, adjudicator-masked trial comparing edoxaban and vitamin K antagonists in AF patients after TAVI. The primary efficacy and safety outcomes were net adverse clinical events (NACE) and major bleeding. RESULTS: Overall, 132 (94.3%) patients with a recent PCI (n = 140) received OAP after TAVI, compared with 692 (55.9%) patients without a recent PCI (n = 1237). Among patients with a recent PCI on OAP agents, use of dual antiplatelet therapy decreased to 5.5%, and use of single antiplatelet therapy (SAPT) increased to 78.0% over 3 months post-randomization. Conversely, use of SAPT predominated at all time points in patients without a recent PCI history. There were no significant differences in the incidence of NACE or other outcomes assessed, except for major bleeding events, which were more frequent in patients with vs without a recent PCI history (hazard ratio [95% confidence interval]: 2.17 [1.27, 3.73]; P = 0.005). CONCLUSIONS: Patients with AF undergoing TAVI with a recent PCI have a similar risk of ischemic events and mortality, but an increased risk of major bleeding compared with patients without a recent PCI.

16.
J Dent ; 143: 104867, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38286192

RESUMO

OBJECTIVES: This study aimed to evaluate silver nanoparticles (AgNPs) obtained by a 'green' route associated or not to tyrosol (TYR) against Streptococcus mutans and Candida albicans in planktonic and biofilms states. METHODS: AgNPs were obtained by a 'green' route using pomegranate extract. The minimum inhibitory concentration (MIC) against S. mutans and C. albicans was determined for AgNPs and TYR combined and alone, and fractional inhibitory concentration index (FICI) was calculated. Single biofilms of C. albicans and S. mutans were cultivated for 24 h and then treated with drugs alone or in combination for 24 h. RESULTS: AgNPs and TYR were effective against C. albicans and S. mutans considering planktonic cells alone and combined. The MIC values obtained for C. albicans was 312.5 µg/mL (AgNPs) and 50 mM (TYR) and for S. mutans was 78.1 µg/mL (AgNPs) and 90 mM (TYR). The combination of these antimicrobial agents was also effective against both microorganisms: 2.44 µg/mL/0.08 mM (AgNPs/TYR) for C. albicans and 39.05 µg/mL /1.25 mM (AgNPs/TYR) for S. mutans. However, synergism was observed only for C. albicans (FICI 0.008). When biofilm was evaluated, a reduction of 4.62 log10 was observed for S. mutans biofilm cells treated with AgNPs (p < 0.05, Tukey test). However, the addition of TYR to AgNPs did not improve their action against biofilm cells (p > 0.05). AgNPs combined with TYR demonstrated a synergistic effect against C. albicans biofilms. CONCLUSIONS: These findings suggest the potential use of AgNPs with or without TYR against C. albicans and S. mutans, important oral pathogens. CLINICAL SIGNIFICANCE: AgNPs obtained by a 'green' route combined or not with TYR can be an alternative to develop several types of oral antimicrobial therapies and biomaterials.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Álcool Feniletílico , Álcool Feniletílico/análogos & derivados , Prata/farmacologia , Anti-Infecciosos/farmacologia , Álcool Feniletílico/farmacologia , Candida albicans , Biofilmes , Streptococcus mutans
17.
Environ Res ; 241: 117548, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37939803

RESUMO

The retreat of glaciers in Antarctica has increased in the last decades due to global climate change, influencing vegetation expansion, and soil physico-chemical and biological attributes. However, little is known about soil microbiology diversity in these periglacial landscapes. This study characterized and compared bacterial and fungal diversity using metabarcoding of soil samples from the Byers Peninsula, Maritime Antarctica. We identified bacterial and fungal communities by amplification of bacterial 16 S rRNA region V3-V4 and fungal internal transcribed spacer 1 (ITS1). We also applied 14C dating on soil organic matter (SOM) from six profiles. Physico-chemical analyses and attributes associated with SOM were evaluated. A total of 14,048 bacterial ASVs were obtained, and almost all samples had 50% of their sequences assigned to Actinobacteriota and Proteobacteria. Regarding the fungal community, Mortierellomycota, Ascomycota and Basidiomycota were the main phyla from 1619 ASVs. We found that soil age was more relevant than the distance from the glacier, with the oldest soil profile (late Holocene soil profile) hosting the highest bacterial and fungal diversity. The microbial indices of the fungal community were correlated with nutrient availability, soil reactivity and SOM composition, whereas the bacterial community was not correlated with any soil attribute. The bacterial diversity, richness, and evenness varied according to presence of permafrost and moisture regime. The fungal community richness in the surface horizon was not related to altitude, permafrost, or moisture regime. The soil moisture regime was crucial for the structure, high diversity and richness of the microbial community, specially to the bacterial community. Further studies should examine the relationship between microbial communities and environmental factors to better predict changes in this terrestrial ecosystem.


Assuntos
Camada de Gelo , Microbiota , Regiões Antárticas , Fungos/genética , Bactérias/genética , Solo/química , Microbiologia do Solo
18.
J Hypertens ; 42(2): 301-307, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37796232

RESUMO

AIM: Leg blood pressure (BP) measurement is needed when arm BP evaluation is not feasible, and calf BP, especially when measured in standing position, may have greater association with cardiovascular remodeling than arm BP. This study evaluated the relationship between calf and arm BP, and investigated whether calf BP would be superior to arm BP in predicting increased arterial stiffness [pulse wave velocity (PWV) > 10 m/s]. METHODS: We evaluated clinical and laboratory characteristics, BP measurements, and PWV in 1397 individuals resident in Baependi, Brazil, between 2017 and 2019. Arm BP was measured in the seated and supine positions while calf BP was measured in supine and standing positions using digital oscillometric devices. Carotid-femoral PWV was measured using a noninvasive mechanotransducer. RESULTS: The sample had 62.7% females, age = 48.1 ±â€Š15.4 years and 8.4% with PWV >10 m/s. Results of linear regression analysis showed that BP values of 140/90 mmHg measured in the arm in supine and seated position were equivalent to calf supine BP values of 164/81 mmHg and 166/78 mmHg and calf standing BP values of 217/137 mmHg and 221/137 mmHg, respectively. Calf-arm BP differences were associated with age, glomerular filtration rate, body mass index, smoking, low-density lipoprotein-cholesterol, diabetes and height. Furthermore, stepwise logistic regression analysis revealed that arm supine systolic BP, but not calf BP measurements, was independently associated with increased arterial stiffness. CONCLUSION: Thresholds of ≈165/80 mmHg and ≈220/135 mmHg could be used for diagnosing hypertension when only calf measurements in supine and standing positions, respectively, are available. Conversely, calf BP was not superior to arm BP in predicting increased arterial stiffness.


Assuntos
Hipertensão , Rigidez Vascular , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Masculino , Pressão Sanguínea/fisiologia , Análise de Onda de Pulso , Rigidez Vascular/fisiologia , Perna (Membro)
19.
Arch Biochem Biophys ; 752: 109858, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38104957

RESUMO

Nitration of tyrosine residues in alpha-synuclein (a-syn) has been detected in different synucleinopathies, including Parkinson's disease. The potential role of 3-nitrotyrosine formation in a-syn, as an oxidative post-translational modification, is still elusive. In this work, we generated well-characterized tyrosine nitrated a-syn monomers and studied their capability to form oligomers and fibrils. We constructed tyrosine to phenylalanine mutants, containing a single tyrosine residue, a-syn mutant Y(125/133/136)F and Y(39/125/133)F) and assessed the impact in a-syn biophysical properties. Nitrated wild-type a-syn and the Y-F mutants, with one 3-nitrotyrosine residue in either the protein's N-terminal or C-terminal region, showed inhibition of fibril formation but retained the capacity of oligomer formation. The inhibition of a-syn fibrillation occurs even when an important amount of unmodified a-syn is still present. We characterized oligomers from both nitrated and non-nitrated forms of the wild-type protein and the mutant forms obtained. Our results indicate that the formation of 3-nitrotyrosine in a-syn could induce an off-pathway oligomer formation which may have an important impact in the development of synucleinopathies.


Assuntos
Doença de Parkinson , Sinucleinopatias , Humanos , alfa-Sinucleína/metabolismo , Nitratos/metabolismo , Doença de Parkinson/metabolismo , Tirosina/metabolismo
20.
An Acad Bras Cienc ; 95(suppl 3): e20230283, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38088640

RESUMO

Microplastics are ubiquitous contaminants of marine ecosystems around the world and Antarctica is no exception. Microplastics can be influenced by sedimentary dynamics mainly on coastal areas where they are more abundant in Antarctica. This study evaluated microplastic contamination in beach environments from two Antarctic Specially Protected Areas, aiming to identify relationships between microplastic numbers and sedimentological parameters on beach sediments. Low numbers of microplastics were found (> 0.5 mm; fibers excluded) - one particle per sample in 4 of 15 samples analyzed - and there is no evidence of widespread contamination. Sedimentological parameters reveal differences between sampled environments, but low numbers of microplastics impaired statistical comparison. All sediment samples are coarse, denoting highenergy depositional environments that are likely little susceptible to microplastic accumulation. Microplastic contamination in the Antarctic coastal ecosystem is heterogeneous, and their detailed characterization assisted by a systematization of methods can improve the understanding of microplastics distribution patterns in the cold coastal ecosystem.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Ecossistema , Regiões Antárticas , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos
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