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1.
Yale J Biol Med ; 97(2): 205-224, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38947104

RESUMO

Neuroinflammation, toxic protein aggregation, oxidative stress, and mitochondrial dysfunction are key pathways in neurodegenerative diseases like Alzheimer's disease (AD). Targeting these mechanisms with antioxidants, anti-inflammatory compounds, and inhibitors of Aß formation and aggregation is crucial for treatment. Marine algae are rich sources of bioactive compounds, including carbohydrates, phenolics, fatty acids, phycobiliproteins, carotenoids, fatty acids, and vitamins. In recent years, they have attracted interest from the pharmaceutical and nutraceutical industries due to their exceptional biological activities, which include anti-inflammation, antioxidant, anticancer, and anti-apoptosis properties. Multiple lines of evidence have unveiled the potential neuroprotective effects of these multifunctional algal compounds for application in treating and managing AD. This article will provide insight into the molecular mechanisms underlying the neuroprotective effects of bioactive compounds derived from algae based on in vitro and in vivo models of neuroinflammation and AD. We will also discuss their potential as disease-modifying and symptomatic treatment strategies for AD.


Assuntos
Doença de Alzheimer , Microalgas , Alga Marinha , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Humanos , Microalgas/química , Microalgas/metabolismo , Alga Marinha/química , Animais , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Produtos Biológicos/isolamento & purificação , Antioxidantes/farmacologia
2.
Surg Endosc ; 35(3): 1046-1051, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32112254

RESUMO

BACKGROUND: Stereoscopic (3D) imaging can be used to facilitate the learning of basic laparoscopic tasks. Its advantages over traditional endoscopic (2D) imaging include better depth perception and spatial orientation. However, the transition between 3D and 2D imaging systems has not been previously studied. This study compares the acquisition of basic laparoscopic skills in a laparoscopic-naïve population using both imaging systems, and explores the possibility of a secondary learning curve in the transition between systems. METHODS: 26 novice learners were randomly allocated into two arms and taught to perform two basic laparoscopic tasks adopted from the fundamentals of laparoscopic surgery (FLS) curriculum, peg transfer (T1) and pattern cutting (T2) using either 2D or 3D imaging systems. These tasks were repeated until proficiency was achieved. Participants in each arm then repeated the tasks in the other viewing system (2D/3D vs 3D/2D). The parameters measured were: (a) time taken to complete the task and (b) number of attempts to achieve proficiency. RESULTS: There was a significant shortening of time required to achieve proficiency in T2 using a 3D system (mean difference-in-differences = - 65.4, 95% CI - 103.6 to - 27.2, t(24) = - 3.5, p value = 0.002) but no difference between 2D and 3D imaging systems for T1, a simpler task. Sub-group analysis of T1 and T2 between the 2D/3D and 3D/2D arms showed the presence of a secondary learning curve in the 2D/3D arm for both tasks, (T1: ß-estimate - 2.68, 95% CI - 3.68 to - 1.68, p value = 0.0003; T2: ß-estimate - 2.45, 95% CI - 3.75 to - 1.14, p value 0.004), but in the 3D/2D arm there was a secondary learning curve only for T2. (ß-estimate 2.60, 95% CI 1.45-3.76, p value 0.001) CONCLUSION: 3D imaging can be an effective tool to speed the acquisition of proficiency in basic laparoscopic tasks for novice learners, especially in more complex tasks such as pattern cutting. The skills learned in 3D imaging can translate into 2D, albeit with a secondary learning curve.


Assuntos
Imageamento Tridimensional , Laparoscopia/educação , Curva de Aprendizado , Competência Clínica , Currículo , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
3.
Heart Lung Circ ; 27(2): 205-211, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28506456

RESUMO

BACKGROUND: There is little data on the prevalence of coronary heart disease (CHD) in the young. The study aimed to estimate the prevalence of asymptomatic CHD in siblings of young patients with myocardial infarction (MI) using coronary computed tomography angiography (CCTA). METHODS: Prospective observational data was collected on siblings of patients aged ≤55 years presenting with acute MI and having coronary stenosis ≥50% on invasive coronary angiography in at least one epicardial coronary artery. Inclusion criteria included ages 30-55 and 30-60 years for males and females respectively. Outcome of interest was obstructive CHD by coronary computer tomography angiography (CCTA), which was defined by either moderate (50-69% stenosis) and/or severe (≥70% stenosis). RESULTS: Fifty participants were studied of whom 20 (40%) were male. Thirty (60%) were current or ex-smokers, 4 (8%) had diabetes, 8 (16%) had hypertension and 26 (52%) had dyslipidaemia. Obstructive CHD by CCTA was detected in 9 (18%, 95% CI 9%-31%) participants and 3 (6%, 95% CI 1%-17%) participants were found to have severe luminal stenosis. The median radiation dose was 3.9 (IQR 0.9) mSv. CONCLUSIONS: Approximately a fifth of siblings of young MI patients were found to have asymptomatic but obstructive CHD detected on CCTA of which one third was severe. This is a group in whom screening for CHD warrants further investigation.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Angiografia Coronária/métodos , Doença das Coronárias/epidemiologia , Vasos Coronários/diagnóstico por imagem , Infarto do Miocárdio/etiologia , Irmãos , Adulto , Doenças Assintomáticas , Doença das Coronárias/complicações , Doença das Coronárias/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Projetos Piloto , Prevalência , Estudos Prospectivos , Taxa de Sobrevida/tendências , Vitória/epidemiologia
4.
Lancet ; 385(9970): 775-84, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25467562

RESUMO

BACKGROUND: Patients are increasingly being admitted with chronic atrial fibrillation, and disease-specific management might reduce recurrent admissions and prolong survival. However, evidence is scant to support the application of this therapeutic approach. We aimed to assess SAFETY--a management strategy that is specific to atrial fibrillation. METHODS: We did a pragmatic, multicentre, randomised controlled trial in patients admitted with chronic, non-valvular atrial fibrillation (but not heart failure). Patients were recruited from three tertiary referral hospitals in Australia. 335 participants were randomly assigned by computer-generated schedule (stratified for rhythm or rate control) to either standard management (n=167) or the SAFETY intervention (n=168). Standard management consisted of routine primary care and hospital outpatient follow-up. The SAFETY intervention comprised a home visit and Holter monitoring 7-14 days after discharge by a cardiac nurse with prolonged follow-up and multidisciplinary support as needed. Clinical reviews were undertaken at 12 and 24 months (minimum follow-up). Coprimary outcomes were death or unplanned readmission (both all-cause), measured as event-free survival and the proportion of actual versus maximum days alive and out of hospital. Analyses were done on an intention-to-treat basis. The trial is registered with the Australian New Zealand Clinical Trials Registry (ANZCTRN 12610000221055). FINDINGS: During median follow-up of 905 days (IQR 773-1050), 49 people died and 987 unplanned admissions were recorded (totalling 5530 days in hospital). 127 (76%) patients assigned to the SAFETY intervention died or had an unplanned readmission (median event-free survival 183 days [IQR 116-409]) and 137 (82%) people allocated standard management achieved a coprimary outcome (199 days [116-249]; hazard ratio 0·97, 95% CI 0·76-1·23; p=0·851). Patients assigned to the SAFETY intervention had 99·5% maximum event-free days (95% CI 99·3-99·7), equating to a median of 900 (IQR 767-1025) of 937 maximum days alive and out of hospital. By comparison, those allocated to standard management had 99·2% (95% CI 98·8-99·4) maximum event-free days, equating to a median of 860 (IQR 752-1047) of 937 maximum days alive and out of hospital (effect size 0·22, 95% CI 0·21-0·23; p=0·039). INTERPRETATION: A post-discharge management programme specific to atrial fibrillation was associated with proportionately more days alive and out of hospital (but not prolonged event-free survival) relative to standard management. Disease-specific management is a possible strategy to improve poor health outcomes in patients admitted with chronic atrial fibrillation. FUNDING: National Health and Medical Research Council of Australia.


Assuntos
Fibrilação Atrial/enfermagem , Serviços de Assistência Domiciliar , Idoso , Fibrilação Atrial/mortalidade , Doença Crônica , Eletrocardiografia Ambulatorial/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Tempo de Internação , Masculino , Equipe de Assistência ao Paciente/organização & administração , Readmissão do Paciente/estatística & dados numéricos , Estudos Prospectivos , Qualidade de Vida , Fatores de Risco , Prevenção Secundária/métodos , Resultado do Tratamento
5.
Exerc Immunol Rev ; 22: 94-109, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26859514

RESUMO

Muscle atrophy is caused by an imbalance in contractile protein synthesis and degradation which can be triggered by various conditions including Type 2 Diabetes Mellitus (T2DM). Reduced muscle quality in patients with T2DM adversely affects muscle function, the capacity to perform activities of daily living, quality of life and ultimately may increase the risk of premature mortality. Systemic inflammation initiated by obesity and prolonged overnutrition not only contributes to insulin resistance typical of T2DM, but also promotes muscle atrophy via decreased muscle protein synthesis and increased ubiquitin-proteasome, lysosomal-proteasome and caspase 3- mediated protein degradation. Emerging evidence suggests that the inflammation-sensitive Nuclear Factor κ B (NF-κB) and Signal Transducer and Activator of Transcription 3 (STAT3) pathways may contribute to muscle atrophy in T2DM. In contrast, exercise appears to be an effective tool in promoting muscle hypertrophy, in part due to its effect on systemic and local (skeletal muscle) inflammation. The current review discusses the role inflammation plays in muscle atrophy in T2DM and the role of exercise training in minimising the effect of inflammatory markers on skeletal muscle. We also report original data from a cohort of obese patients with T2DM compared to age-matched controls and demonstrate that patients with T2DM have 60% higher skeletal muscle expression of the atrophy transcription factor FoxO1. This review concludes that inflammatory pathways in muscle, in particular, NF-κB, potentially contribute to T2DM-mediated muscle atrophy. Further in-vivo and longitudinal human research is required to better understand the role of inflammation in T2DM-mediated atrophy and the anti-inflammatory effect of exercise training under these conditions.


Assuntos
Diabetes Mellitus Tipo 2 , Atividades Cotidianas , Exercício Físico , Genes Sintéticos , Humanos , Músculo Esquelético , Atrofia Muscular , NF-kappa B , Qualidade de Vida , Proteínas Recombinantes
6.
Heart Lung Circ ; 25(10): 955-60, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27265644

RESUMO

Myocardial infarction (MI) in the "young" is a significant problem, however there is scarcity of data on premature coronary heart disease (CHD) and MI in the "young". This may lead to under-appreciation of important differences that exist between "young" MI patients versus an older cohort. Traditional differences described in the risk factor profile of younger MI compared to older patients include a higher prevalence of smoking, family history of premature CHD and male gender. Recently, other potentially important differences have been described. Most "young" MI patients will present with non-ST elevation MI but the proportion presenting with ST-elevation MI is increasing. Coronary angiography usually reveals less extensive disease in "young" MI patients, which has implications for management. Short-term prognosis of "young" MI patients is better than for older patients, however contemporary data raises concerns regarding longer-term outcomes, particularly in those with reduced left ventricular systolic function. Here we review the differences in rate, risk factor profile, presentation, management and prognosis between "young" and older MI patients.


Assuntos
Infarto do Miocárdio , Fumar , Função Ventricular Esquerda , Fatores Etários , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/fisiopatologia , Doença da Artéria Coronariana/terapia , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Prognóstico , Fatores de Risco , Fumar/efeitos adversos , Fumar/fisiopatologia , Fumar/terapia
7.
Rev Cardiovasc Med ; 16(1): 20-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25813793

RESUMO

Heart failure with preserved ejection fraction (HFPEF) is common, and at least half of patients presenting with signs and symptoms of heart failure are found to have preserved left ventricular systolic function. They have high mortality and morbidity and exert a substantial impact on health care costs worldwide. A range of conditions has been shown to predispose individuals to development of diastolic dysfunction and HFPEF. Chronic hypertension is the most common cause; it has been suggested that up to 60% of patients with HFPEF are hypertensive. Coronary artery disease, obesity, and diabetes are some of the other common contributory factors. Early detection of asymptomatic patients identified as at risk of developing this syndrome has the potential to reduce the risk of subsequent heart failure; this may be of benefit to focus our attention on prevention and intervention strategies in this population.

9.
Cardiovasc Ultrasound ; 12: 8, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24529199

RESUMO

AIMS: 2D speckle tracking echocardiography allows for assessment of left ventricular (LV) torsional deformation as a composite function of the radial, longitudinal and circumferential fibres. We test the hypothesis that post-exercise LV torsional dynamics are more sensitive markers for myocardial dysfunction than resting measures, and better predictors for exercise capacity compared to post-exercise LV diastolic filling pressure (E/e'). METHODS: We studied 88 patients referred for stress echocardiogram. Treadmill exercise was performed using Bruce protocol, and echo images were acquired using GE Vivid 7. LV rotational dynamics were analysed by speckle tracking method using the GE ECHOPAC software. Tertiles were defined according to exercise capacity measured by the achieved metabolic equivalents (METS) adjusted for age and gender. Comparison was made between LV torsional dynamics and E/e' to correlate with METS to predict exercise capacity. RESULTS: Mean age of the study population was 58 years, 48% females. Patients with systolic dysfunction or evidence of ischaemia were excluded from the analysis. No significant correlation was found between METS and LV torsion measures at rest. There was statistically significant correlation between METS and post-exercise LV torsion (r=0.34, p=0.001), twist velocity increase (r=0.27, p=0.01), and incremental change in torsion (r=0.22, p<0.05). In addition, a correlation was also shown between post-exercise E/e' and METS (r=-0.33, p=0.002). CONCLUSION: Post-exercise LV torsional dynamics correlate with exercise capacity and may be a useful tool for assessing LV myocardial function in subjects with normal LVEF.


Assuntos
Teste de Esforço , Ventrículos do Coração/fisiopatologia , Anormalidade Torcional/diagnóstico por imagem , Anormalidade Torcional/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Ecocardiografia/métodos , Módulo de Elasticidade , Técnicas de Imagem por Elasticidade/métodos , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Volume Sistólico
10.
JACC Heart Fail ; 12(2): 275-286, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37498272

RESUMO

BACKGROUND: Clinical and echocardiographic features predict incident heart failure (HF), but the optimal strategy for combining them is unclear. OBJECTIVES: This study sought to define an effective means of using echocardiography in HF risk evaluation. METHODS: The same clinical and echocardiographic evaluation was obtained in 2 groups with HF risk factors: a training group (n = 926, followed to 7 years) and a validation group (n = 355, followed to 10 years). Clinical risk was categorized as low, intermediate, and high using 4-year ARIC (Atherosclerosis Risk In Communities) HF risk score cutpoints of 9% and 33%. A risk stratification algorithm based on clinical risk and echocardiographic markers of stage B HF (SBHF) (abnormal global longitudinal strain [GLS], diastolic dysfunction, or left ventricular hypertrophy) was developed using a classification and regression tree analysis and was validated. RESULTS: HF developed in 12% of the training group, including 9%, 18%, and 73% of low-, intermediate-, and high-risk patients. HF occurred in 8.6% of stage A HF and 19.4% of SBHF (P < 0.001), but stage A HF with clinical risk of ≥9% had similar outcome to SBHF. Abnormal GLS (HR: 2.92 [95% CI: 1.95-4.37]; P < 0.001) was the strongest independent predictor of HF. Normal GLS and diastolic function reclassified 61% of the intermediate-risk group into the low-risk group (HF incidence: 12%). In the validation group, 11% developed HF over 4.5 years; 4%, 17%, and 39% of low-, intermediate-, and high-risk groups. Similar results were obtained after exclusion of patients with known coronary artery disease. The echocardiographic parameters also provided significant incremental value to the ARIC score in predicting new HF admission (C-statistic: 0.78 [95% CI: 0.71-0.84] vs 0.83 [95% CI: 0.77-0.88]; P = 0.027). CONCLUSIONS: Clinical risk assessment is adequate to classify low and high HF risk. Echocardiographic evaluation reclassifies 61% of intermediate-risk patients.


Assuntos
Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Humanos , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Ecocardiografia/métodos , Fatores de Risco , Hipertrofia Ventricular Esquerda , Medição de Risco , Função Ventricular Esquerda , Volume Sistólico , Prognóstico
11.
Fitoterapia ; 176: 106025, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38768797

RESUMO

Algae and its metabolites have been a popular subject of research in numerous fields over the years. Various reviews have been written on algal bioactive components, but a specific focus on Antarctic-derived algae is seldom reviewed. Due to the extreme climate conditions of Antarctica, it is hypothesized that the acclimatized algae may have given rise to a new set of bioactive compounds as a result of adaptation. Although most studies done on Antarctic algae are based on ecological and physiological studies, as well as in the field of nanomaterial synthesis, some studies point out the potential therapeutic properties of these compounds. As an effort to shed light on a different application of Antarctic algae, this review focuses on evaluating its different medicinal properties, including antimicrobial, anticancer, antioxidative, anti-inflammatory, and skin protective effects.


Assuntos
Antioxidantes , Regiões Antárticas , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Humanos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/isolamento & purificação , Antineoplásicos/farmacologia , Antineoplásicos/isolamento & purificação , Produtos Biológicos/farmacologia , Produtos Biológicos/isolamento & purificação , Estrutura Molecular
12.
Curr Pharm Des ; 29(35): 2827-2840, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37936453

RESUMO

Today, cardiovascular diseases are among the biggest public health threats worldwide. Atherosclerosis, a chronic inflammatory disease with complex aetiology and pathogenesis, predispose many of these conditions, including the high mortality rate-causing ischaemic heart disease and stroke. Nevertheless, despite the alarming prevalence and absolute death rate, established treatments for atherosclerosis are unsatisfactory in terms of efficacy, safety, and patient acceptance. The rapid advancement of technologies in healthcare research has paved new treatment approaches, namely cell-based and nanoparticle-based therapies, to overcome the limitations of conventional therapeutics. This paper examines the different facets of each approach, discusses their principles, strengths, and weaknesses, analyses the main targeted pathways and their contradictions, provides insights on current trends as well as highlights any unique mechanisms taken in recent years to combat the progression of atherosclerosis.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Doença da Artéria Coronariana , Isquemia Miocárdica , Humanos , Aterosclerose/tratamento farmacológico , Doença Crônica
13.
Biology (Basel) ; 12(8)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37627026

RESUMO

Microalgae are well known for their metal sorption capacities, but their potential in the remediation of hydrophobic organic compounds has received little attention in polar regions. We evaluated in the laboratory the ability of an Antarctic microalga to remediate diesel hydrocarbons and also investigated physiological changes consequent upon diesel exposure. Using a polyphasic taxonomic approach, the microalgal isolate, WCY_AQ5_1, originally sampled from Greenwich Island (South Shetland Islands, maritime Antarctica) was identified as Tritostichococcus sp. (OQ225631), a recently erected lineage within the redefined Stichococcus clade. Over a nine-day experimental incubation, 57.6% of diesel (~3.47 g/L) was removed via biosorption and biodegradation, demonstrating the strain's potential for phytoremediation. Fourier transform infrared spectroscopy confirmed the adsorption of oil in accordance with its hydrophobic characteristics. Overall, degradation predominated over sorption of diesel. Chromatographic analysis confirmed that the strain efficiently metabolised medium-chain length n-alkanes (C-7 to C-21), particularly n-heneicosane. Mixotrophic cultivation using diesel as the organic carbon source under a constant light regime altered the car/chl-a ratio and triggered vacuolar activities. A small number of intracellular lipid droplets were observed on the seventh day of cultivation in transmission electron microscopic imaging. This is the first confirmation of diesel remediation ability in an Antarctic green microalga.

14.
Heart Rhythm ; 20(8): 1178-1187, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37172670

RESUMO

Conduction system pacing (CSP)-His bundle pacing (HBP) and left bundle branch area pacing (LBBAP)-are emerging alternatives to biventricular pacing (BVP) for cardiac resynchronization therapy (CRT) in heart failure. However, evidence is largely limited to small and observational studies. We conducted a meta-analysis including a total of 15 randomized controlled trials (RCTs) and non-RCTs that compare CSP (HBP and LBBAP) with BVP in patients with CRT indications. We assessed the mean differences in QRS duration (QRSd), pacing threshold, left ventricular ejection fraction (LVEF), and New York Heart Association (NYHA) class score. CSP resulted in a pooled mean QRSd improvement of -20.3 ms (95% confidence interval [CI] -26.1 to -14.5 ms; P < .05; I2= 87.1%) vs BVP. For LVEF, a weighted mean increase of 5.2% (95% CI 3.5%-6.9%; P < .05; I2 = 55.6) was observed after CSP vs BVP. The mean NYHA score was reduced by -0.40 (95% CI -0.6 to -0.2; P < .05; I2 = 61.7) after CSP vs BVP. A subgroup analysis of outcomes stratified by LBBAP and HBP demonstrated statistically significant weighted mean improvements of QRSd and LVEF with both CSP modalities compared with BVP. LBBAP resulted in NYHA improvement compared with BVP, without differences between CSP subgroups. LBBAP is associated with a significantly lowered mean pacing threshold of -0.51 V (95% CI -0.68 to -0.38 V) while HBP had increased the mean threshold (0.62 V; 95% CI -0.03 to 1.26 V) compared with BVP; however, this was associated with significant heterogeneity. Overall, both CSP techniques are feasible and effective CRT alternatives for heart failure. Further RCTs are needed to establish long-term efficacy and safety.


Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Humanos , Fascículo Atrioventricular , Eletrocardiografia/métodos , Resultado do Tratamento , Sistema de Condução Cardíaco , Doença do Sistema de Condução Cardíaco , Terapia de Ressincronização Cardíaca/métodos , Função Ventricular Esquerda , Volume Sistólico , Insuficiência Cardíaca/terapia
15.
Plants (Basel) ; 12(13)2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37447097

RESUMO

Research has confirmed that the utilisation of Antarctic microorganisms, such as bacteria, yeasts and fungi, in the bioremediation of diesel may provide practical alternative approaches. However, to date there has been very little attention towards Antarctic microalgae as potential hydrocarbon degraders. Therefore, this study focused on the utilisation of an Antarctic microalga in the bioremediation of diesel. The studied microalgal strain was originally obtained from a freshwater ecosystem in Paradise Bay, western Antarctic Peninsula. When analysed in systems with and without aeration, this microalgal strain achieved a higher growth rate under aeration. To maintain the growth of this microalga optimally, a conventional one-factor-at a-time (OFAT) analysis was also conducted. Based on the optimized parameters, algal growth and diesel degradation performance was highest at pH 7.5 with 0.5 mg/L NaCl concentration and 0.5 g/L of NaNO3 as a nitrogen source. This currently unidentified microalga flourished in the presence of diesel, with maximum algal cell numbers on day 7 of incubation in the presence of 1% v/v diesel. Chlorophyll a, b and carotenoid contents of the culture were greatest on day 9 of incubation. The diesel degradation achieved was 64.5% of the original concentration after 9 days. Gas chromatography analysis showed the complete mineralisation of C7-C13 hydrocarbon chains. Fourier transform infrared spectroscopy analysis confirmed that strain WCY_AQ5_3 fully degraded the hydrocarbon with bioabsorption of the products. Morphological and molecular analyses suggested that this spherical, single-celled green microalga was a member of the genus Micractinium. The data obtained confirm that this microalga is a suitable candidate for further research into the degradation of diesel in Antarctica.

16.
Physiol Genomics ; 44(3): 211-9, 2012 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-22147268

RESUMO

Chronic atrial fibrillation (AF) is a complication associated with the dilated atria of patients with valvular heart disease and contributes to worsened pathology. We examined microRNA (miRNA) expression profiles in right and left atrial appendage tissue from valvular heart disease (VHD) patients. Right atrial (RA) appendage from patients undergoing coronary artery bypass grafting and left atrial (LA) appendage from healthy hearts, not used for transplant, were used as controls. There was no detectable effect of chronic AF on miRNA expression in LA tissue, but miRNA expression in RA was strongly influenced by AF, with 47 miRNAs (15 higher, 32 lower) showing differential expression between the AF and control sinus rhythm groups. VHD induced different changes in miRNA expression in LA compared with RA. Fifty-three (12 higher, 41 lower) miRNAs were altered by VHD in LA, compared with 5 (4 higher, 1 lower) in RA tissue. miRNA profiles also differed between VHD-LA and VHD-RA (13 higher, 26 lower). We conclude that VHD and AF influence miRNA expression patterns in LA and RA, but these are affected differently by disease progression and by the development of AF. These findings provide new insights into the progression of VHD.


Assuntos
Apêndice Atrial/metabolismo , Fibrilação Atrial/etiologia , Fibrilação Atrial/metabolismo , Regulação da Expressão Gênica/fisiologia , Doenças das Valvas Cardíacas/complicações , MicroRNAs/metabolismo , Idoso , Análise de Variância , Feminino , Perfilação da Expressão Gênica , Doenças das Valvas Cardíacas/fisiopatologia , Humanos , Modelos Lineares , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vitória
17.
BMJ Case Rep ; 15(5)2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35550326

RESUMO

A woman in her 50s with a background of chronic obstructive pulmonary disease secondary to smoking presented with intermittent chest tightness, dyspnoea and vomiting for 4 days. A presumed diagnosis of acute coronary syndrome (ACS) was made based on dynamic ischaemic ECG changes and elevation in high-sensitivity cardiac troponin T levels. She underwent emergent coronary angiography which demonstrated mild coronary artery disease with left ventriculography suggestive of mid-wall variant Takotsubo cardiomyopathy. Thyroid function tests performed to investigate sinus tachycardia were consistent with hyperthyroidism, and her thyroid-stimulating hormone receptor antibody was elevated. A diagnosis of thyroid storm was made in the setting of a newly diagnosed Graves' disease and the patient was subsequently commenced on guideline-based therapy. This case demonstrates that Takotsubo cardiomyopathy, a mimic of ACS, is a possible complication of thyroid storm and therefore hyperthyroidism should be considered in the list of differentials in patients presenting with Takotsubo cardiomyopathy.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Cardiomiopatia de Takotsubo , Crise Tireóidea , Síndrome Coronariana Aguda/complicações , Angiografia Coronária/efeitos adversos , Doença da Artéria Coronariana/complicações , Feminino , Humanos , Cardiomiopatia de Takotsubo/complicações , Cardiomiopatia de Takotsubo/diagnóstico , Crise Tireóidea/complicações , Crise Tireóidea/diagnóstico
18.
JACC Cardiovasc Imaging ; 15(8): 1380-1387, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35926896

RESUMO

BACKGROUND: Current guidelines distinguish stage B heart failure (SBHF) (asymptomatic left ventricular [LV] dysfunction) from stage A heart failure (SAHF) (asymptomatic with heart failure [HF] risk factors) on the basis of myocardial infarction, LV remodeling (hypertrophy or reduced ejection fraction [EF]) or valvular disease. However, subclinical HF with preserved EF may not be identified with these criteria. OBJECTIVES: The purpose of this study was to assess the prediction of incident HF with global longitudinal strain (GLS) in patients with SAHF and SBHF. METHODS: The authors analyzed echocardiograms (including GLS) in 447 patients (age 65 ± 11 years; 77% male) enrolled in a prospective study of HF in individuals at risk of incident HF, with normal or mildly impaired EF (≥40%). Long-term follow-up was obtained via data linkage. Analysis was performed using a competing risks model. RESULTS: After a median of 9 years of follow-up, 50 (10%) of the 447 patients had new HF admissions, and 87 (18%) died. In multivariable analysis, all imaging variables were independent predictors of HF admissions, including left ventricular ejection fraction (LVEF) (HR: 0.97 [95% CI: 0.94-0.99]), LV mass index (HR: 1.01 [95% CI: 1.00-1.02]), left atrial volume index (HR: 1.02 [95% CI: 1.00-1.05]), and E/e' (HR: 1.05 [95% CI: 1.01-1.24]), incremental to clinical variables (age and Charlson comorbidity score). However, the addition of GLS provided value incremental to both clinical and other echocardiographic parameters (P = 0.004). Impaired GLS (<18%) (HR: 4.09 [95% CI: 1.87-8.92]) was independent and incremental to all clinical and other echocardiographic variables in predicting HF, and impaired LVEF, left ventricular hypertrophy, left atrial enlargement, high E/e', or SBHF were not predictive. CONCLUSIONS: The inclusion of GLS as a criterion for SBHF would add independent and incremental information to standard markers of SBHF for the prediction of subsequent HF admissions.


Assuntos
Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Idoso , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Fatores de Risco , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda
19.
J Am Soc Echocardiogr ; 35(2): 187-195, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34508839

RESUMO

BACKGROUND: Heart failure (HF) remains a common complication for patients with coronary artery disease (CAD), especially after acute myocardial infarction. Although left ventricular ejection fraction (LVEF) is conventionally used to assess cardiac function for risk stratification, it has been shown in other settings to underestimate the risk of HF compared with global longitudinal strain (GLS). Moreover, most evidence pertains to early-onset HF. We sought the clinical and myocardial predictors for late-onset HF in patients with CAD. METHODS: We analyzed echocardiograms (including GLS) in 334 patients with CAD (ages 65 ± 11 years, 77% male) who were enrolled in the Nurse-Led Intervention for Less Chronic Heart Failure trial, a prospective, randomized controlled trial that compared standard care with nurse-led intervention to prevent HF in individuals at risk of incident HF. Long-term (9 years) follow-up was obtained via data linkage. Analysis was performed using a competing-risk model. RESULTS: Baseline LVEF values were normal or mildly impaired (LVEF ≥ 40%) in all subjects. After a median of 9 years of follow-up, 50 (15%) of the 334 patients had new HF admissions, and 68 (20%) died. In a competing-risk model, HF was associated with GLS (hazard ratio = 1.15 [1.05-1.25], P = .001), independent of estimated glomerular filtration rate (hazard ratio = 0.98 [0.97-0.99], P = .045), Charlson comorbidity score (hazard ratio = 1.64 [1.25-2.15], P < .001), or E/e' (hazard ratio = 1.08 [1.02-1.14], P = .01). Global longitudinal strain-but not conventional echocardiographic measures-added incremental value to a clinical model based on age, gender, and Charlson score (area under the curve, 0.78-0.83, P = .01). Global longitudinal strain was still associated with HF development in patients taking baseline angiotensin convertase enzyme inhibitors (hazard ratio = 1.21 [1.11-1.31], P < .01) and baseline beta-blockers (1.17 [1.09, 1.26]; P < .01). Mortality was associated with older men, risk factors (hypertension or diabetes), and comorbidities (AF and chronic kidney disease). CONCLUSIONS: Global longitudinal strain is independently associated with risk of incident HF in patients admitted with CAD and provides incremental prognostic value to standard markers. Identifying an at-risk subgroup using GLS may be the focus of future randomized controlled trails to enable targeted therapeutic intervention.


Assuntos
Doença da Artéria Coronariana , Insuficiência Cardíaca , Idoso , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Volume Sistólico , Função Ventricular Esquerda
20.
Plants (Basel) ; 11(1)2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-35009130

RESUMO

Oil pollution such as diesel poses a significant threat to the environment. Due to this, there is increasing interest in using natural materials mainly from agricultural waste as organic oil spill sorbents. Oil palm's empty fruit bunch (EFB), a cost-effective material, non-toxic, renewable resource, and abundantly available in Malaysia, contains cellulosic materials that have been proven to show a good result in pollution treatment. This study evaluated the optimum screening part of EFB that efficiently absorbs oil and the physicochemical characterisation of untreated and treated EFB fibre using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The treatment conditions were optimised using one-factor-at-a-time (OFAT), which identified optimal treatment conditions of 170 °C, 20 min, 0.1 g/cm3, and 10% diesel, resulting in 23 mL of oil absorbed. The predicted model was highly significant in statistical Response Surface Methodology (RSM) and confirmed that all the parameters (temperature, time, packing density, and diesel concentration) significantly influenced the oil absorbed. The predicted values in RSM were 175 °C, 22.5 min, 0.095 g/cm3, and 10%, which resulted in 24 mL of oil absorbed. Using the experimental values generated by RSM, 175 °C, 22.5 min, 0.095 g/cm3, and 10%, the highest oil absorption achieved was 24.33 mL. This study provides further evidence, as the data suggested that RSM provided a better approach to obtain a high efficiency of oil absorbed.

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