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1.
BMC Plant Biol ; 24(1): 327, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658826

RESUMO

Oomycetes are filamentous organisms that resemble fungi in terms of morphology and life cycle, primarily due to convergent evolution. The success of pathogenic oomycetes lies in their ability to adapt and overcome host resistance, occasionally transitioning to new hosts. During plant infection, these organisms secrete effector proteins and other compounds during plant infection, as a molecular arsenal that contributes to their pathogenic success. Genomic sequencing, transcriptomic analysis, and proteomic studies have revealed highly diverse effector repertoires among different oomycete pathogens, highlighting their adaptability and evolution potential.The obligate biotrophic oomycete Plasmopara viticola affects grapevine plants (Vitis vinifera L.) causing the downy mildew disease, with significant economic impact. This disease is devastating in Europe, leading to substantial production losses. Even though Plasmopara viticola is a well-known pathogen, to date there are scarce reviews summarising pathogenicity, virulence, the genetics and molecular mechanisms of interaction with grapevine.This review aims to explore the current knowledge of the infection strategy, lifecycle, effector molecules, and pathogenicity of Plasmopara viticola. The recent sequencing of the Plasmopara viticola genome has provided new insights into understanding the infection strategies employed by this pathogen. Additionally, we will highlight the contributions of omics technologies in unravelling the ongoing evolution of this oomycete, including the first in-plant proteome analysis of the pathogen.


Assuntos
Oomicetos , Doenças das Plantas , Vitis , Oomicetos/patogenicidade , Oomicetos/fisiologia , Doenças das Plantas/microbiologia , Vitis/microbiologia , Vitis/genética , Virulência , Evolução Biológica , Interações Hospedeiro-Patógeno
2.
Rev Port Cardiol ; 2024 Apr 05.
Artigo em Inglês, Português | MEDLINE | ID: mdl-38583858

RESUMO

INTRODUCTION AND OBJECTIVES: The association between exercise and coronary atherosclerosis still remains unclarified. We aimed to analyze the prevalence of high coronary atherosclerotic burden in veteran athletes, considering cardiovascular (CV) risk and volume of exercise. METHODS: A total of 105 asymptomatic male veteran athletes (48±5.6 years old) were studied. A high coronary atherosclerotic burden was defined as one of the following characteristics in coronary computed tomography angiography: calcium score >100, >75th percentile, obstructive plaques, involving left main, three-vessels or two-vessels including proximal anterior descending artery, segment Involvement Score >5 or CT-adapted Leaman score ≥5. CV risk was stratified by SCORE2 and volume of exercise by metabolic equivalent task score. RESULTS: Most athletes (n=88) were engaged in endurance sports for 17.1±9.8 years, with a median exercise volume of 66 [IQR 44-103] metabolic equivalent of tasks/hour/week. The mean Systematic Coronary Risk Evaluation 2 was 2.8±1.5%; 76.9% of athletes had a low-moderate risk and none a very high risk. High coronary atherosclerotic burden was present in 25.7% athletes. Athletes with high cardiovascular risk and high exercise volume (above the median) showed significantly high coronary atherosclerotic burden compared to those with low-moderate risk and high volume (50.0% vs. 15.6%; p=0.017). Among athletes with low to moderate risk, a high volume of exercise tended to be protective, while in those with low volume, there was similar rate of high coronary atherosclerotic burden, regardless of CV risk. CONCLUSIONS: A combination of higher volume of exercise and high cardiovascular risk revealed the worst association with coronary atherosclerosis in veteran athletes. The relationship between these variables is controversial, but integrating exercise characteristics and risk assessment into preparticipation evaluation is essential.

3.
Sci Rep ; 14(1): 7085, 2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38528043

RESUMO

Left ventricular (LV) hypertrophy is a common finding in patients with severe aortic stenosis (AS). Cardiac magnetic resonance (CMR) is the gold-standard technique to evaluate LV remodeling. Our aim was to assess the prevalence and describe the patterns of LV adaptation in AS patients before and after surgical aortic valve replacement (AVR). Prospective study of 130 consecutive patients (71y [IQR 68-77y], 48% men) with severe AS, referred for surgical AVR. Patterns of LV remodeling were assessed by CMR. Besides normal LV ventricular structure, four other patterns were considered: concentric remodeling, concentric hypertrophy, eccentric hypertrophy, and adverse remodeling. At baseline CMR study: mean LV indexed mass: 81.8 ± 26.7 g/m2; mean end-diastolic LV indexed volume: 85.7 ± 23.1 mL/m2 and median geometric remodeling ratio: 0.96 g/mL [IQR 0.82-1.08 g/mL]. LV hypertrophy occurred in 49% of subjects (concentric 44%; eccentric 5%). Both normal LV structure and concentric remodeling had a prevalence of 25% among the cohort; one patient had an adverse remodeling pattern. Asymmetric LV wall thickening was present in 55% of the patients, with predominant septal involvement. AVR was performed in 119 patients. At 3-6 months after AVR, LV remodeling changed to: normal ventricular geometry in 60%, concentric remodeling in 27%, concentric hypertrophy in 10%, eccentric hypertrophy in 3% and adverse remodeling (one patient). Indexes of AS severity, LV systolic and diastolic function and NT-proBNP were significantly different among the distinct patterns of remodeling. Several distinct patterns of LV remodelling beyond concentric hypertrophy occur in patients with classical severe AS. Asymmetric hypertrophy is a common finding and LV response after AVR is diverse.


Assuntos
Estenose da Valva Aórtica , Valva Aórtica , Masculino , Humanos , Feminino , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Remodelação Ventricular/fisiologia , Estudos Prospectivos , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Espectroscopia de Ressonância Magnética , Função Ventricular Esquerda/fisiologia
4.
Biofilm ; 7: 100185, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38444517

RESUMO

The ability of bacteria to adhere to and form biofilms on food contact surfaces poses serious challenges, as these may lead to the cross-contamination of food products. Biomimetic topographic surface modifications have been explored to enhance the antifouling performance of materials. In this study, the topography of two plant leaves, Brassica oleracea var. botrytis (cauliflower, CF) and Brassica oleracea capitate (white cabbage, WC), was replicated through wax moulding, and their antibiofilm potential was tested against single- and dual-species biofilms of Escherichia coli and Pseudomonas putida. Biomimetic surfaces exhibited higher roughness values (SaWC = 4.0 ± 1.0 µm and SaCF = 3.3 ± 1.0 µm) than the flat control (SaF = 0.6 ± 0.2 µm), whilst the CF surface demonstrated a lower interfacial free energy (ΔGiwi) than the WC surface (-100.08 mJ m-2 and -71.98 mJ m-2, respectively). The CF and WC surfaces had similar antibiofilm effects against single-species biofilms, achieving cell reductions of approximately 50% and 60% for E. coli and P. putida, respectively, compared to the control. Additionally, the biomimetic surfaces led to reductions of up to 60% in biovolume, 45% in thickness, and 60% in the surface coverage of single-species biofilms. For dual-species biofilms, only the E. coli strain growing on the WC surface exhibited a significant decrease in the cell count. However, confocal microscopy analysis revealed a 60% reduction in the total biovolume and surface coverage of mixed biofilms developed on both biomimetic surfaces. Furthermore, dual-species biofilms were mainly composed of P. putida, which reduced E. coli growth. Altogether, these results demonstrate that the surface properties of CF and WC biomimetic surfaces have the potential for reducing biofilm formation.

5.
Arq Bras Cardiol ; 121(1): e20230242, 2024.
Artigo em Português, Inglês | MEDLINE | ID: mdl-38477763

RESUMO

BACKGROUND: The European Society of Cardiology guidelines recommend an LDL-cholesterol (LDL-C) < 55 mg/dL for patients with established cardiovascular disease. While the Friedewald equation to estimate LDL-C is still widely used, the newer Martin-Hopkins equation has shown greater accuracy. OBJECTIVES: We aimed to assess: A) the proportion of patients reaching LDL-C goal and the therapies used in a tertiary center; B) the impact of using the Martin-Hopkins method instead of Friedewald's on the proportion of controlled patients. METHODS: A single-center cross-sectional study including consecutive post-myocardial infarction patients followed by 20 cardiologists in a tertiary hospital. Data was collected retrospectively from clinical appointments that took place after April 2022. For each patient, the LDL-C levels and attainment of goals were estimated from an ambulatory lipid profile using both Friedewald and Martin-Hopkins equations. A two-tailed p-value of < 0.05 was considered statistically significant for all tests. RESULTS: Overall, 400 patients were included (aged 67 ± 13 years, 77% male). Using Friedewald's equation, the median LDL-C under therapy was 64 (50-81) mg/dL, and 31% had LDL-C within goals. High-intensity statins were used in 64% of patients, 37% were on ezetimibe, and 0.5% were under PCSK9 inhibitors. Combination therapy of high-intensity statin + ezetimibe was used in 102 patients (26%). Applying the Martin-Hopkins method would reclassify a total of 31 patients (7.8%). Among those deemed controlled by Friedewald's equation, 27 (21.6%) would have a Martin-Hopkins' LDL-C above goals. CONCLUSIONS: Less than one-third of post-myocardial infarction patients had LDL-C within the goal. Applying the Martin-Hopkins equation would reclassify one-fifth of presumably controlled patients into the non-controlled group.


FUNDAMENTO: As diretrizes da Sociedade Europeia de Cardiologia recomendam um nível de colesterol LDL (LDL-C) < 55 mg/dL para pacientes com doença cardiovascular estabelecida. Embora a fórmula de Friedewald ainda seja amplamente utilizada para estimar o LDL-C, a fórmula mais recente de Martin-Hopkins mostrou maior precisão. OBJETIVOS: Nosso objetivo foi avaliar: A) a proporção de pacientes que atingiram a meta de LDL-C e as terapias utilizadas em um centro terciário; B) o impacto da utilização do método de Martin-Hopkins em vez do método de Friedewald na proporção de pacientes controlados. MÉTODOS: Estudo transversal monocêntrico, incluindo pacientes consecutivos pós-infarto do miocárdio, acompanhados por 20 cardiologistas, em um hospital terciário. Os dados foram coletados retrospectivamente de consultas clínicas realizadas após abril de 2022. Para cada paciente, os níveis de LDL-C e o atingimento das metas foram estimados a partir de um perfil lipídico ambulatorial, utilizando as fórmulas de Friedewald e Martin-Hopkins. Um valor-p bicaudal < 0,05 foi considerado estatisticamente significativo para todos os testes. RESULTADOS: Foram incluídos 400 pacientes (com 67 ± 13 anos, 77% do sexo masculino). Utilizando a fórmula de Friedewald, a mediana de LDL-C sob terapia foi de 64 (50-81) mg/dL, e 31% tinham LDL-C dentro da meta. Estatinas de alta intensidade foram usadas em 64% dos pacientes, 37% estavam em uso de ezetimiba e 0,5% estavam em uso de inibidores de PCSK9. A terapia combinada de estatina de alta intensidade + ezetimiba foi utilizada em 102 pacientes (26%). A aplicação do método de Martin-Hopkins reclassificaria um total de 31 pacientes (7,8%). Entre aqueles considerados controlados pela fórmula de Friedewald, 27 (21,6%) teriam LDL-C estimado por Martin-Hopkins acima da meta. CONCLUSÕES: Menos de um terço dos pacientes pós-infarto do miocárdio apresentaram LDL-C dentro da meta. A aplicação da fórmula de Martin-Hopkins reclassificaria um quinto dos pacientes presumivelmente controlados no grupo de pacientes não controlados.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Infarto do Miocárdio , Humanos , Masculino , Feminino , Estudos Transversais , Pró-Proteína Convertase 9 , LDL-Colesterol , Objetivos , Estudos Retrospectivos , Ezetimiba , Síndrome
6.
Acta Cardiol ; : 1-10, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38420970

RESUMO

Purpose: Exercise intolerance and dyspnoea are clinical symptoms in both heart failure (HF) reduced ejection fraction (HFrEF) and chronic obstructive pulmonary disease (COPD), which are suggested to be associated with musculoskeletal dysfunction. We tested the hypothesis that HFrEF + COPD patients would present lower muscle strength and greater fatigue compared to compared to the COPD group. Methods: We included 25 patients with HFrEF + COPD (100% male, age 67.8 ± 6.9) and 25 patients with COPD alone (100% male, age 66.1 ± 9.1). In both groups, COPD severity was determined as moderate-to-severe according to the GOLD classification (FEV1/FVC < 0.7 and predicted post-bronchodilator FEV1 between 30%-80%). Knee flexor-extensor muscle performance (torque, work, power and fatigue) were measured by isokinetic dynamometry in age and sex-matched patients with HFrEF + COPD and COPD alone; Functional capacity was assessed by the cardiopulmonary exercise test, the 6-min walk test (6MWT) and the four-minute step test. Results: The COPD group exhibited reduced lung function compared to the HFrEF + COPD group, as evidenced by lower FEV1/FVC (58.0 ± 4.0 vs. 65.5 ± 13.9; p < 0.0001, respectively) and FEV1 (51.3 ± 17.0 vs. 62.5 ± 17.4; p = 0.026, respectively) values. Regarding musculoskeletal function, the HFrEF + COPD group showed a knee flexor muscles impairment, however this fact was not observed in the knee extensors muscles. Power peak of the knee flexor corrected by muscle mass was significantly correlated with the 6MWT (r = 0.40; p < 0.05), number of steps (r = 0.30; p < 0.05) and work ratepeak (r = 0.40; p < 0.05) in the HFrEF + COPD and COPD groups. Conclusion: The presence of HFrEF in patients with COPD worsens muscular weakness when compared to isolated COPD.

7.
Mol Ther Nucleic Acids ; 35(1): 102122, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38333674

RESUMO

Antimicrobial resistance (AMR) is a growing concern because it causes microorganisms to develop resistance to drugs commonly used to treat infections. This results in increased difficulty in treating infections, leading to higher mortality rates and significant economic effects. Investing in new antimicrobial agents is, therefore, necessary to prevent and control AMR. Antimicrobial nucleic acids have arisen as potential key players in novel therapies for AMR infections. They have been designed to serve as antimicrobials and to act as adjuvants to conventional antibiotics or to inhibit virulent mechanisms. This new category of antimicrobial drugs consists of antisense oligonucleotides and oligomers, DNAzymes, and transcription factor decoys, differing in terms of structure, target molecules, and mechanisms of action. They are synthesized using nucleic acid analogs to enhance their resistance to nucleases. Because bacterial envelopes are generally impermeable to oligonucleotides, delivery into the cytoplasm typically requires the assistance of nanocarriers, which can affect their therapeutic potency. Given that numerous factors contribute to the success of these antimicrobial drugs, this review aims to provide a summary of the key advancements in the use of oligonucleotides for treating bacterial infections. Their mechanisms of action and the impact of factors such as nucleic acid design, target sequence, and nanocarriers on the antimicrobial potency are discussed.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38246861

RESUMO

Myocardial fibrosis (MF) takes part in left ventricular (LV) remodeling in patients with aortic stenosis (AS), driving the transition from hypertrophy to heart failure. The structural changes that occur in this transition are not fully enlightened. AIM: to describe histopathology changes at endomyocardial biopsy (EMB) in patients with severe AS referred to surgical aortic valve replacement (AVR); to correlate them with LV tissue characterization from pre-operative cardiac magnetic resonance (CMR). METHODS: one-hundred-fifty-eight patients (73[68-77]years, 50%women) referred for surgical AVR because of severe symptomatic AS, with pre-operative CMR (n = 143) with late gadolinium enhancement (LGE), T1, T2 mapping and extracellular volume fraction (ECV) quantification. Intra-operative septal EMB was obtained in 129 patients. MF was assessed through Masson´s Trichrome histochemistry. Immunohistochemistry was performed for both inflammatory cells and extracellular matrix (ECM) characterization (Type I Collagen, Fibronectin, Tenascin C). RESULTS: non-ischemic LGE was present in 106 patients (67.1%) (median fraction:5.0% [2.0-9.7]). Native T1 was above normal: 1053 ms[1024-1071] and T2 within normal range (39.3 ms[37.3-42.0]). Median MF was 11.9%[6.54-19.97], with predominant type I collagen perivascular distribution (95.3%). Subendocardial cardiomyocyte ischemic-like changes were identified in 45% of EMB. There was no inflammation, despite ECM remodeling expression. MF quantification at EMB was correlated with LGE mass (p = 0.008) but not with global ECV (p = 0.125). CONCLUSION: patients with severe symptomatic AS referred for surgical AVR have unspecific histological myocardial changes, including signs of cardiomyocyte ischemic insult. ECM remodeling is ongoing, with MF heterogeneity. These features may be recognized by comprehensive CMR protocols. However, no single CMR parameter captures the burden of MF and histological myocardial changes in this setting.

10.
Arq. bras. cardiol ; 121(1): e20230242, jan. 2024. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1533726

RESUMO

Resumo Fundamento: As diretrizes da Sociedade Europeia de Cardiologia recomendam um nível de colesterol LDL (LDL-C) < 55 mg/dL para pacientes com doença cardiovascular estabelecida. Embora a fórmula de Friedewald ainda seja amplamente utilizada para estimar o LDL-C, a fórmula mais recente de Martin-Hopkins mostrou maior precisão. Objetivos: Nosso objetivo foi avaliar: A) a proporção de pacientes que atingiram a meta de LDL-C e as terapias utilizadas em um centro terciário; B) o impacto da utilização do método de Martin-Hopkins em vez do método de Friedewald na proporção de pacientes controlados. Métodos: Estudo transversal monocêntrico, incluindo pacientes consecutivos pós-infarto do miocárdio, acompanhados por 20 cardiologistas, em um hospital terciário. Os dados foram coletados retrospectivamente de consultas clínicas realizadas após abril de 2022. Para cada paciente, os níveis de LDL-C e o atingimento das metas foram estimados a partir de um perfil lipídico ambulatorial, utilizando as fórmulas de Friedewald e Martin-Hopkins. Um valor-p bicaudal < 0,05 foi considerado estatisticamente significativo para todos os testes. Resultados: Foram incluídos 400 pacientes (com 67 ± 13 anos, 77% do sexo masculino). Utilizando a fórmula de Friedewald, a mediana de LDL-C sob terapia foi de 64 (50-81) mg/dL, e 31% tinham LDL-C dentro da meta. Estatinas de alta intensidade foram usadas em 64% dos pacientes, 37% estavam em uso de ezetimiba e 0,5% estavam em uso de inibidores de PCSK9. A terapia combinada de estatina de alta intensidade + ezetimiba foi utilizada em 102 pacientes (26%). A aplicação do método de Martin-Hopkins reclassificaria um total de 31 pacientes (7,8%). Entre aqueles considerados controlados pela fórmula de Friedewald, 27 (21,6%) teriam LDL-C estimado por Martin-Hopkins acima da meta. Conclusões: Menos de um terço dos pacientes pós-infarto do miocárdio apresentaram LDL-C dentro da meta. A aplicação da fórmula de Martin-Hopkins reclassificaria um quinto dos pacientes presumivelmente controlados no grupo de pacientes não controlados.


Abstract Background: The European Society of Cardiology guidelines recommend an LDL-cholesterol (LDL-C) < 55 mg/dL for patients with established cardiovascular disease. While the Friedewald equation to estimate LDL-C is still widely used, the newer Martin-Hopkins equation has shown greater accuracy. Objectives: We aimed to assess: A) the proportion of patients reaching LDL-C goal and the therapies used in a tertiary center; B) the impact of using the Martin-Hopkins method instead of Friedewald's on the proportion of controlled patients. Methods: A single-center cross-sectional study including consecutive post-myocardial infarction patients followed by 20 cardiologists in a tertiary hospital. Data was collected retrospectively from clinical appointments that took place after April 2022. For each patient, the LDL-C levels and attainment of goals were estimated from an ambulatory lipid profile using both Friedewald and Martin-Hopkins equations. A two-tailed p-value of < 0.05 was considered statistically significant for all tests. Results: Overall, 400 patients were included (aged 67 ± 13 years, 77% male). Using Friedewald's equation, the median LDL-C under therapy was 64 (50-81) mg/dL, and 31% had LDL-C within goals. High-intensity statins were used in 64% of patients, 37% were on ezetimibe, and 0.5% were under PCSK9 inhibitors. Combination therapy of high-intensity statin + ezetimibe was used in 102 patients (26%). Applying the Martin-Hopkins method would reclassify a total of 31 patients (7.8%). Among those deemed controlled by Friedewald's equation, 27 (21.6%) would have a Martin-Hopkins' LDL-C above goals. Conclusions: Less than one-third of post-myocardial infarction patients had LDL-C within the goal. Applying the Martin-Hopkins equation would reclassify one-fifth of presumably controlled patients into the non-controlled group.

12.
Prev Med Rep ; 38: 102587, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38288262

RESUMO

Introduction: The COVID-19 pandemic may lead to reduced physical activity (PA) in health care workers (HCWs). Objective: To evaluate leisure and transport-related PA in HCW of a COVID-19-dedicated hospital during the first wave of the COVID-19 pandemic. Methods: This is a cross-sectional study with a sample of 1,527 HCWs. Socioeconomic aspects, occupational characteristics, and engagement in leisure and transport-related PA were investigated through an online survey administered in August of 2020. Results: More than 80 % HCWs performed < 150 min/week of leisure-related PA, and 85 % performed ≤ 30 min/day transport-related PA. Being male was associated with more PA (OR: 1.93; 95 % CI:1.40-2.66) and transport-related PA; working in nursing, physical therapy, and cleaning/housekeeping services was associated with low PA (OR: 0.70; 95 % CI:0.51-0.95). Physicians and administrative staff were less active in transport-related PA. Conclusions: HCWs working in a COVID-19 hospital had low levels of PA in the domains of leisure and transportation.

13.
World J Gastrointest Oncol ; 16(1): 234-243, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38292846

RESUMO

BACKGROUND: In patients with metastatic colorectal cancer (mCRC), the treatment options are limited and have been proved to be affected by rat sarcoma virus (RAS) mutational status. In RAS wild-type (wt) patients, the combination of anti-epidermal growth factor receptor (EGFR) monoclonal antibodies with chemotherapy (CT) is more effective than CT alone. On the other hand, RAS-mutated patients are not eligible for treatment with anti-EGFR antibodies. CASE SUMMARY: Eleven patients with initially RAS-mutated mCRC were followed from diagnosis to May 2022. At the time of cell-free DNA determination, five patients had undergone one CT line, five patients had undergone two CT lines, and one patient had undergone three CT lines (all in combination with bevacizumab). At the second and third treatment lines [second line (2L), third line (3L)], patients with neo-RAS wt received a combination of CT and cetuximab. In neo-RAS wt patients treated with anti-EGFR, our findings indicated an increase in progression-free survival for both 2L and 3L (14.5 mo, P = 0.119 and 3.9 mo, P = 0.882, respectively). Regarding 2L overall survival, we registered a slight increase in neo-RAS wt patients treated with anti-EGFR (33.6 mo vs 32.4 mo, P = 0.385). At data cut-off, two patients were still alive: A RAS-mutated patient undergoing 3L treatment and a neo-RAS wt patient who received 2L treatment with anti-EGFR (ongoing). CONCLUSION: Our case series demonstrated that monitoring RAS mutations in mCRC by liquid biopsy may provide an additional treatment line for neo-RAS wt patients.

14.
Cardiovasc Pathol ; 69: 107589, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38029890

RESUMO

BACKGROUND: Myocardial adaptation to severe aortic stenosis (AS) is a complex process that involves myocardial fibrosis (MF) beyond cardiomyocyte hypertrophy. Perfusion impairment is believed to be involved in myocardial remodeling in chronic pressure overload. AIM: To describe morphological and ultrastructural myocardial changes at endomyocardial tissue sampling, possibly reflecting subendocardial ischemia, in a group of patients with severe AS referred to surgical aortic valve replacement (AVR), with no previous history of ischemic cardiomyopathy. METHODS: One-hundred-fifty-eight patients (73 [68-77] years, 50% women) referred for surgical AVR because of severe symptomatic AS with preoperative clinical and imaging study and no previous history of ischemic cardiomyopathy. Intra-operative septal endomyocardial sampling was obtained in 129 patients. Tissue sections were stained with Masson´s Trichrome for MF quantification and periodic acid-Schiff (PAS) staining was performed to assess the presence of intracellular glycogen. Ultrastructure was analyzed through Transmission electron microscopy (TEM). RESULTS: MF totalized a median fraction of 11.90% (6.54-19.97%) of EMB, with highly prevalent perivascular involvement (95.3%). None of the samples had histological evidence of myocardial infarction. In 58 patients (45%) we found subendocardial groups of cardiomyocytes with cytoplasmatic enlargement, vacuolization and myofiber derangement, surrounded by extensive interstitial fibrosis. These cardiomyocytes were PAS positive, PAS-diastase resistant and Alcian Blue/PAS indicative of the presence of neutral intracellular glyco-saccharides. At TEM there were signs of cardiomyocyte degeneration with sarcomere disorganization and reduction, organelle rarefaction but no signs of intracellular specific accumulation. CONCLUSION: Almost half of the patients with severe AS referred for surgical AVR have histological and ultrastructural signs of subendocardial cardiomyocyte ischemic insult. It might be inferred that local perfusion imbalance contributes to myocardial remodeling and fibrosis in chronic pressure overload.


Assuntos
Estenose da Valva Aórtica , Cardiomiopatias , Cardiopatias Congênitas , Implante de Prótese de Valva Cardíaca , Humanos , Feminino , Masculino , Estenose da Valva Aórtica/cirurgia , Miocárdio/patologia , Cardiopatias Congênitas/patologia , Fibrose , Cardiomiopatias/patologia , Isquemia , Função Ventricular Esquerda
15.
Int J Telerehabil ; 15(1): e6475, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38046554

RESUMO

Aims: To evaluate the effectiveness of a hybrid cardiac telerehabilitation (HCTR) program after acute coronary syndrome (ACS) on patient quality of life (QoL) and physical activity indices throughout phases 2-3 and establish predictors for hybrid program self-selection. Methodology: This single-centre longitudinal retrospective study included patients who attended a cardiac rehabilitation program (CRP) between 2018-2021. Patients self-selected between two groups: Group 1 - conventional CRP (CCRP); Group 2 - HCTR. Baseline characteristics were registered. EuroQol-5D (EQ-5D) and International Physical Activity Questionnaire (IPAQ) were applied at three times: T0 - phase 2 onset; T1 - phase 3 onset; T2 - 3 months after T1. Results: 59 patients participated (Group 1 - 27; Group 2 - 32). We found significant between-group differences regarding occupation (p=0.003). Diabetic patients were less likely to self-select into HCTR (OR=0.21; p<0.05). EQ-5D visual analogue scale and IPAQ result significantly improved between T0-T2 only for HCTR (p=0.001; p=0.021). Conclusions: HCTR was superior to CCRP on physical activity indices and QoL of ACS patients.

16.
Biomolecules ; 13(11)2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-38002253

RESUMO

The application of graphene-based materials in medicine has led to significant technological breakthroughs. The remarkable properties of these carbon materials and their potential for functionalization with various molecules and compounds make them highly attractive for numerous medical applications. To enhance their functionality and applicability, extensive research has been conducted on surface modification of graphene (GN) and its derivatives, including modifications with antimicrobials, metals, polymers, and natural compounds. This review aims to discuss recent and relevant studies related to advancements in the formulation of graphene composites, addressing their antimicrobial and/or antibiofilm properties and evaluating their biocompatibility, with a primary focus on their biomedical applications. It was concluded that GN surface modification, particularly with compounds intrinsically active against bacteria (e.g., antimicrobial peptides, silver and copper nanomaterials, and chitosan), has resulted in biomaterials with improved antimicrobial performance. Furthermore, the association of GN materials with non-natural polymers provides composites with increased biocompatibility when interfaced with human tissues, although with slightly lower antimicrobial efficacy. However, it is crucial to highlight that while modified GN materials hold huge potential, their widespread use in the medical field is still undergoing research and development. Comprehensive studies on safety, long-term effects, and stability are essential before their adoption in real-world medical scenarios.


Assuntos
Anti-Infecciosos , Grafite , Humanos , Grafite/farmacologia , Grafite/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Prata/farmacologia , Prata/química , Polímeros/química
17.
Antibiotics (Basel) ; 12(11)2023 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-37998822

RESUMO

Chemically modified carbon nanotubes are recognized as effective materials for tackling bacterial infections. In this study, pristine multi-walled carbon nanotubes (p-MWCNTs) were functionalized with nitric acid (f-MWCNTs), followed by thermal treatment at 600 °C, and incorporated into a poly(dimethylsiloxane) (PDMS) matrix. The materials' textural properties were evaluated, and the roughness and morphology of MWCNT/PDMS composites were assessed using optical profilometry and scanning electron microscopy, respectively. The antibiofilm activity of MWCNT/PDMS surfaces was determined by quantifying culturable Escherichia coli and Staphylococcus aureus after 24 h of biofilm formation. Additionally, the antibacterial mechanisms of MWCNT materials were identified by flow cytometry, and the cytotoxicity of MWCNT/PDMS composites was tested against human kidney (HK-2) cells. The results revealed that the antimicrobial activity of MWCNTs incorporated into a PDMS matrix can be efficiently tailored through nitric acid functionalization, and it can be increased by up to 49% in the absence of surface carboxylic groups in f-MWCNT samples heated at 600 °C and the presence of redox activity of carbonyl groups. MWCNT materials changed the membrane permeability of both Gram-negative and Gram-positive bacteria, while they only induced the production of ROS in Gram-positive bacteria. Furthermore, the synthesized composites did not impact HK-2 cell viability, confirming the biocompatibility of MWCNT composites.

18.
Children (Basel) ; 10(11)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38002898

RESUMO

There is growing concern about the relationship between screen use by young children and negative effects on their development, as children with developmental and socioemotional impairments tend to have difficulties in their relationships and increased academic problems. The aim of our study was to analyse the relationship between the use of multimedia devices and paediatric symptoms in children below 5 years old. Data from 534 Portuguese parents of children aged from 18 to 57 months were collected via a self-report questionnaire. Children's daily exposure to multimedia devices was nearly 2 h per day. Paediatric symptoms were positively associated with watching television and screen time and negatively associated with parents' working hours. Touchscreen use was more frequent among girls and older children. Parents' working hours comprised the most significant predictor of paediatric symptoms. Our findings reinforce past findings on the adverse links between the use of multimedia devices and paediatric symptoms and also highlight the influence of other variables like the child's age and gender, as well as parental factors. The need to both create a more comprehensive framework regarding the long-term effects of multimedia device use and delineate effective strategies for prevention and intervention with parents and children is discussed.

19.
bioRxiv ; 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37662317

RESUMO

During embryogenesis, yolk-sac and intra-embryonic-derived hematopoietic progenitors, comprising the precursors of adult hematopoietic stem cells, converge into the fetal liver. With a new staining strategy, we defined all non-hematopoietic components of the fetal liver and found that hepatoblasts are the major producers of hematopoietic growth factors. We identified mesothelial cells, a novel component of the stromal compartment, producing Kit ligand, a major hematopoietic cytokine. A high-definition imaging dataset analyzed using a deep-learning based pipeline allowed the unambiguous identification of hematopoietic and stromal populations, and enabled determining a neighboring network composition, at the single cell resolution. Throughout active hematopoiesis, progenitors preferentially associate with hepatoblasts, but not with stellate or endothelial cells. We found that, unlike yolk sac-derived progenitors, intra-embryonic progenitors respond to a chemokine gradient created by CXCL12-producing stellate cells. These results revealed that FL hematopoiesis is a spatiotemporal dynamic process, defined by an environment characterized by low cytokine concentrations.

20.
Nanomaterials (Basel) ; 13(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37764632

RESUMO

Graphene has been broadly studied, particularly for the fabrication of biomedical devices, owing to its physicochemical and antimicrobial properties. In this study, the antibiofilm efficacy of graphene nanoplatelet (GNP)-based composites as coatings for urinary catheters (UCs) was investigated. GNPs were functionalized with nitrogen (N-GNP) and incorporated into a polydimethylsiloxane (PDMS) matrix. The resulting materials were characterized, and the N-GNP/PDMS composite was evaluated against single- and multi-species biofilms of Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Both biofilm cell composition and structure were analyzed. Furthermore, the antibacterial mechanisms of action of N-GNP were explored. The N-GNP/PDMS composite showed increased hydrophobicity and roughness compared to PDMS. In single-species biofilms, this composite significantly reduced the number of S. aureus, P. aeruginosa, and K. pneumoniae cells (by 64, 41, and 29%, respectively), and decreased S. aureus biofilm culturability (by 50%). In tri-species biofilms, a 41% reduction in total cells was observed. These results are aligned with the outcomes of the biofilm structure analysis. Moreover, N-GNP caused changes in membrane permeability and triggered reactive oxygen species (ROS) synthesis in S. aureus, whereas in Gram-negative bacteria, it only induced changes in cell metabolism. Overall, the N-GNP/PDMS composite inhibited biofilm development, showing the potential of these carbon materials as coatings for UCs.

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