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1.
Analyst ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38895826

RESUMO

Algal growth depends strongly on phosphorus (P) as a key nutrient, underscoring the significance of monitoring P levels. Algal species display a sensitive response to fluctuations in P availability, notably through the expression of alkaline phosphatase (AP) when challenged with P-depletion. As such, alkaline phosphatase activity (APA) serves as a valuable metric for P availability, offering insights into how algae utilize and fix available P resources. However, current APA quantification methods lack single cell resolution, while also being time- and reagent consuming. Microfluidics offers a promising cost-effective solution to these limitations, providing a platform for precise single-cell analysis. In this study, a trap-based microfluidic device was integrated with a commercially available AP live stain to study the single cell APA response of a model algae strain, Chlamydomonas reinhardtii, when exposed to different exogenous P levels. A three-step culture-starve-spike process was used to induce APA in cells cultured under two different basal P levels (1 and 21 mM). When challenged with different spiked P levels (ranging from 0.1-41 mM), C. reinhardtii cells demonstrated a highly heterogeneous APA response. Two-way ANOVA confirmed that this response is influenced by both spiked and basal P levels. Utilizing an unsupervised machine learning approach (HDBSCAN), distinct subpopulations of C. reinhardtii cells were identified exhibiting varying levels of APA at the single-cell level. These subpopulations encompass significant groups of individual cells with either notably high or low APA, contributing to the overall behavior of the cohorts. Considerable intrapopulation differences in APA were observed across cohorts with similar average behavior. For instance, while some cohorts exhibited a concentrated distribution around the overall average APA, others displayed subpopulations dispersed across a wider range of APA levels. This underscores the potential bias introduced by analyzing a small number of cells in bulk, which may skew results by overrepresenting extreme behavioral subpopulations. The findings if this study highlight the need for analytical approaches that account for single cell heterogeneity in APA and demonstrate the utility of microfluidics as a well-suited means for such investigations. This study illuminates the complexities of APA regulation at the single cell level, providing crucial insights that advance our understanding of algal phosphorus metabolism and environmental responses.

2.
Sensors (Basel) ; 23(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37960497

RESUMO

Heart diseases rank among the most fatal health concerns globally, with the majority being preventable through early diagnosis and effective treatment. Electrocardiogram (ECG) analysis is critical in detecting heart diseases, as it captures the heart's electrical activities. For continuous monitoring, wearable electrocardiographic devices must ensure user comfort over extended periods, typically 24 to 48 h. These devices demand specialized algorithms with low computational complexity to accommodate memory and power consumption constraints. One of the most crucial aspects of ECG signals is accurately detecting heartbeat intervals, specifically the R peaks. In this study, we introduce a novel algorithm designed for wearable devices, offering two primary attributes: robustness against noise and low computational complexity. Our algorithm entails fitting a least-squares parabola to the ECG signal and adaptively shaping it as it sweeps through the signal. Notably, our proposed algorithm eliminates the need for band-pass filters, which can inadvertently smooth the R peaks, making them more challenging to identify. We compared the algorithm's performance using two extensive databases: the meta-database QT database and the BIH-MIT database. Importantly, our method does not necessitate the precise localization of the ECG signal's isoelectric line, contributing to its low computational complexity. In the analysis of the QT database, our algorithm demonstrated a substantial advantage over the classical Pan-Tompkins algorithm and maintained competitiveness with state-of-the-art approaches. In the case of the BIH-MIT database, the performance results were more conservative; they continued to underscore the real-world utility of our algorithm in clinical contexts.


Assuntos
Cardiopatias , Dispositivos Eletrônicos Vestíveis , Humanos , Processamento de Sinais Assistido por Computador , Eletrocardiografia/métodos , Algoritmos
3.
Stroke ; 53(11): 3289-3294, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35946402

RESUMO

BACKGROUND: We analyzed the main factors associated with intravenous thrombolysis (IVT) in patients with minor ischemic stroke. METHODS: Data were obtained from a prospective, government-mandated, population-based registry of stroke code patients in Catalonia (6 Comprehensive Stroke Centers, 8 Primary Stroke Centers, and 14 TeleStroke Centers). We selected patients diagnosed with ischemic stroke and National Institutes of Health Stroke Scale (NIHSS) ≤5 at hospital admission from January 2016 to December 2020. We excluded patients with a baseline modified Rankin Scale score of ≥3, absolute contraindication for IVT, unknown stroke onset, or admitted to hospital beyond 4.5 after stroke onset. The main outcome was treatment with IVT. We performed univariable and binary logistic regression analyses to identify the most important factors associated with IVT. RESULTS: We included 2975 code strokes; 1433 (48.2%) received IVT of which 30 (2.1%) had a symptomatic hemorrhagic transformation. Patients treated with IVT as compared to patients who did not receive IVT were more frequently women, had higher NIHSS, arrived earlier to hospital, were admitted to a Comprehensive Stroke Centers, and had large vessel occlusion. After binary logistic regression, NIHSS score 4 to 5 (odds ratio, 40.62 [95% CI, 31.73-57.22]; P<0.001) and large vessel occlusion (odds ratio, 16.39 [95% CI, 7.25-37.04]; P<0.001) were the strongest predictors of IVT. Younger age, female sex, baseline modified Rankin Scale score of 0, earlier arrival to hospital (<120 minutes after stroke onset), and the type of stroke center were also independently associated with IVT. The weight of large vessel occlusion on IVT was higher in patients with lower NIHSS. CONCLUSIONS: Minor stroke female patients, with higher NIHSS, arriving earlier to the hospital, presenting with large vessel occlusion and admitted to a Comprehensive Stroke Centers were more likely to receive intravenous thrombolysis.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Feminino , Humanos , Isquemia Encefálica/terapia , Estudos Prospectivos , Resultado do Tratamento , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/complicações , Terapia Trombolítica , Trombectomia , Fibrinolíticos/uso terapêutico
4.
Sensors (Basel) ; 22(5)2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35270994

RESUMO

In this paper, we addressed the problem of dataset scarcity for the task of network intrusion detection. Our main contribution was to develop a framework that provides a complete process for generating network traffic datasets based on the aggregation of real network traces. In addition, we proposed a set of tools for attribute extraction and labeling of traffic sessions. A new dataset with botnet network traffic was generated by the framework to assess our proposed method with machine learning algorithms suitable for unbalanced data. The performance of the classifiers was evaluated in terms of macro-averages of F1-score (0.97) and the Matthews Correlation Coefficient (0.94), showing a good overall performance average.


Assuntos
Algoritmos , Aprendizado de Máquina , Projetos de Pesquisa
5.
Stroke ; 52(12): 3908-3917, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34455823

RESUMO

BACKGROUND AND PURPOSE: We evaluated whether stroke severity, functional outcome, and mortality are different in patients with ischemic stroke with or without coronavirus disease 2019 (COVID-19) infection. METHODS: A prospective, observational, multicentre cohort study in Catalonia, Spain. Recruitment was consecutive from mid-March to mid-May 2020. Patients had an acute ischemic stroke within 48 hours and a previous modified Rankin Scale (mRS) score of 0 to 3. We collected demographic data, vascular risk factors, prior mRS score, National Institutes of Health Stroke Scale score, rate of reperfusion therapies, logistics, and metrics. Primary end point was functional outcome at 3 months. Favourable outcome was defined depending on the previous mRS score. Secondary outcome was mortality at 3 months. We performed mRS shift and multivariable analyses. RESULTS: We evaluated 701 patients (mean age 72.3±13.3 years, 60.5% men) and 91 (13%) had COVID-19 infection. Median baseline National Institutes of Health Stroke Scale score was higher in patients with COVID-19 compared with patients without COVID-19 (8 [3-18] versus 6 [2-14], P=0.049). Proportion of patients with a favourable functional outcome was 33.7% in the COVID-19 and 47% in the non-COVID-19 group. However, after a multivariable logistic regression analysis, COVID-19 infection did not increase the probability of unfavourable functional outcome. Mortality rate was 39.3% among patients with COVID-19 and 16.1% in the non-COVID-19 group. In the multivariable logistic regression analysis, COVID-19 infection was a risk factor for mortality (hazard ratio, 3.14 [95% CI, 2.10-4.71]; P<0.001). CONCLUSIONS: Patients with ischemic stroke and COVID-19 infection have more severe strokes and a higher mortality than patients with stroke without COVID-19 infection. However, functional outcome is comparable in both groups.


Assuntos
COVID-19/fisiopatologia , Estado Funcional , AVC Isquêmico/fisiopatologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , COVID-19/complicações , Estudos de Casos e Controles , Feminino , Humanos , AVC Isquêmico/complicações , AVC Isquêmico/mortalidade , AVC Isquêmico/terapia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Mortalidade , Análise Multivariada , Prognóstico , Estudos Prospectivos , SARS-CoV-2 , Índice de Gravidade de Doença , Trombectomia , Terapia Trombolítica
6.
BMC Public Health ; 21(1): 473, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750362

RESUMO

BACKGROUND: Venezuela is in the throes of a complex humanitarian crisis that is one of the worst in decades to impact any country outside of wartime. This case analysis describes the challenges faced by the ongoing Maracaibo Aging Study (MAS) during the deteriorating conditions in Venezuela. When the MAS began in 1997, it focused on memory-related disorders. Since then, strategic planning and proactive community participation allowed us to anticipate and address logistical, funding, and ethical challenges, and facilitated the enrollment and retention of more than 2500 subjects over 55 years of age. All participants, who are residents of the city of Maracaibo, Venezuela, underwent various assessments on several occasions. Here, we discuss how our approach to implementing a longitudinal, population-based study of age-related conditions has allowed our research program to continue throughout this period of political, economic, and social upheaval. DISCUSSION: As the social context in Venezuela became more complicated, new challenges emerged, and strategies to sustain the study and participation were refined. We identified five main mechanisms through which the evolving humanitarian crisis has affected implementation of the MAS: 1) community dynamics; 2) morale of researchers, staff, and participants; 3) financial feasibility; 4) components of the research process; and 5) impact on the health of staff, participants, and their families. Strategies to compensate for the impact on these components were implemented, based on inputs from community members and staff. Improved communication, greater involvement of stakeholders, broadening the scope of the project, and strengthening international collaboration have been the most useful strategies. Particular demands emerged, related to the increased mortality and comorbidities of participants and staff, and deterioration of basic services and safety. CONCLUSION: Although the MAS has faced numerous obstacles, it has been possible to continue a longitudinal research project throughout the humanitarian crisis, because our research team has engaged the community deeply and developed a sense of mutual commitment, and also because our project has provided funding to help keep researchers employed, somewhat attenuating the brain drain.


Assuntos
Participação da Comunidade , Hispânico ou Latino , Envelhecimento , Humanos , Pesquisadores , Venezuela
7.
J Stroke Cerebrovasc Dis ; 30(7): 105824, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33906070

RESUMO

INTRODUCTION: Recent small subcortical infarcts (RSSI) are considered an acute manifestation of cerebral small vessel disease (CSVD). We assessed whether the topography of RSSI was related to CSVD markers on magnetic resonance imaging (MRI). MATERIAL AND METHODS: We screened the local registries of two independent stroke centers in Catalonia and selected patients with a symptomatic RSSI on MRI performed during admission. RSSI location was classified into brainstem, supratentorial subcortical structures (SSS), and centrum semiovale (CSO) regions. Clinical variables, including vascular risk factors, were collected. Radiological markers of CSVD on MRI were evaluated individually and by means of the global CSVD burden score. The associations between each RSSI location and CSVD markers were studied in uni- and multivariate logistic regression analysis. RESULTS: Among 475 patients with RSSI, 152 (32%) had an infarct in the brainstem, 227 (48%) in SSS, and 96 (20%) in CSO region. The median CSVD burden score was 2 (IQR, 1-3). After adjusting for confounding factors, a RSSI in CSO was associated with higher periventricular and deep white matter hyperintensity scores [OR 1.64 (95% CI, 1.16-2.33), and OR 1.44 (95% CI, 1.07-1.93), respectively]. Higher CSVD burden score was positively associated with CSO [OR 1.48 (95% CI, 1.22-1.81)] and inversely associated with SSS [0.85 (95% CI, 0.72-0.99)] location after adjusting for relevant confounders. CONCLUSIONS: CSO RSSI were related to a higher burden of CSVD, particularly to white matter hyperintensities, compared to other RSSI locations. The pathophysiological significance of such findings should be investigated in the future with advanced neuroimaging techniques.


Assuntos
Infartos do Tronco Encefálico/etiologia , Infarto Cerebral/etiologia , Doenças de Pequenos Vasos Cerebrais/complicações , Leucoencefalopatias/etiologia , Idoso , Idoso de 80 Anos ou mais , Infartos do Tronco Encefálico/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Feminino , Humanos , Leucoencefalopatias/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença
8.
Sensors (Basel) ; 19(9)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064133

RESUMO

With the rapid deployment of the Internet of Things and cloud computing, it is necessary to enhance authentication protocols to reduce attacks and security vulnerabilities which affect the correct performance of applications. In 2019 a new lightweight IoT-based authentication scheme in cloud computing circumstances was proposed. According to the authors, their protocol is secure and resists very well-known attacks. However, when we evaluated the protocol we found some security vulnerabilities and drawbacks, making the scheme insecure. Therefore, we propose a new version considering login, mutual authentication and key agreement phases to enhance the security. Moreover, we include a sub-phase called evidence of connection attempt which provides proof about the participation of the user and the server. The new scheme achieves the security requirements and resists very well-known attacks, improving previous works. In addition, the performance evaluation demonstrates that the new scheme requires less communication-cost than previous authentication protocols during the registration and login phases.

9.
Sensors (Basel) ; 19(4)2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30769781

RESUMO

The monitoring and processing of electrocardiogram (ECG) beats have been actively studied in recent years: new lines of research have even been developed to analyze ECG signals using mobile devices. Considering these trends, we proposed a simple and low computing cost algorithm to process and analyze an ECG signal. Our approach is based on the use of linear regression to segment the signal, with the goal of detecting the R point of the ECG wave and later, to separate the signal in periods for detecting P, Q, S, and T peaks. After pre-processing of ECG signal to reduce the noise, the algorithm was able to efficiently detect fiducial points, information that is transcendental for diagnosis of heart conditions using machine learning classifiers. When tested on 260 ECG records, the detection approach performed with a Sensitivity of 97.5% for Q-point and 100% for the rest of ECG peaks. Finally, we validated the robustness of our algorithm by developing an ECG sensor to register and transmit the acquired signals to a mobile device in real time.


Assuntos
Eletrocardiografia/métodos , Coração/fisiologia , Algoritmos , Coração/diagnóstico por imagem , Humanos , Modelos Lineares , Processamento de Sinais Assistido por Computador
10.
Ophthalmology ; 125(6): 807-814, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29310962

RESUMO

PURPOSE: To determine which nocturnal blood pressure (BP) parameters (low levels or extreme dipper status) are associated with an increased risk of glaucomatous damage in Hispanics. DESIGN: Observational cross-sectional study. PARTICIPANTS: A subset (n = 93) of the participants from the Maracaibo Aging Study (MAS) who met the study eligibility criteria were included. These participants, who were at least 40 years of age, had measurements for optical tomography coherence, visual field (VF) tests, 24-hour BP, office BP, and intraocular pressure <22 mmHg. METHODS: Univariate and multivariate logistic regression analyses under the generalized estimating equations (GEE) framework were used to examine the relationships between glaucomatous damage and BP parameters, with particular attention to decreases in nocturnal BP. MAIN OUTCOME MEASURES: Glaucomatous optic neuropathy (GON) based on the presence of optic nerve damage and VF defects. RESULTS: The mean age was 61.9 years, and 87.1% were women. Of 185 eyes evaluated, 19 (26.5%) had signs of GON. Individuals with GON had significantly lower 24-hour and nighttime diastolic BP levels than those without. However, results of the multivariate GEE models indicated that the glaucomatous damage was not related to the average systolic or diastolic BP levels measured over 24 hours, daytime, or nighttime. In contrast, extreme decreases in nighttime systolic and diastolic BP (>20% compared with daytime BP) were significant risk factors for glaucomatous damage (odds ratio, 19.78 and 5.55, respectively). CONCLUSIONS: In this population, the link between nocturnal BP and GON is determined by extreme dipping effects rather than low nocturnal BP levels alone. Further studies considering extreme decreases in nocturnal BP in individuals at high risk of glaucoma are warranted.


Assuntos
Envelhecimento/fisiologia , Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia , Glaucoma de Ângulo Aberto/fisiopatologia , Hipotensão/fisiopatologia , Doenças do Nervo Óptico/fisiopatologia , Idoso , Monitorização Ambulatorial da Pressão Arterial , Estudos Transversais , Feminino , Glaucoma de Ângulo Aberto/diagnóstico , Gonioscopia , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Doenças do Nervo Óptico/diagnóstico , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica , Tonometria Ocular , Venezuela , Campos Visuais/fisiologia
11.
Alzheimers Dement ; 14(2): 140-147, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28943198

RESUMO

INTRODUCTION: There are few longitudinal studies of dementia in developing countries. We used longitudinal data from the Maracaibo Aging Study to accurately determine the age- and sex-specific incidence of dementia in elderly Latin Americans. METHODS: The Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition, Text Revision) was used to diagnose dementia, which was classified as Alzheimer's disease, vascular dementia, or other. Age- and sex-specific incidence was estimated as the number of new cases of dementia divided by person-years (p-y) of follow-up. RESULTS: The incidence of all dementia diagnoses was 9.10 per 1000 p-y (95% confidence interval [CI] 7.13-11.44; 8026 total p-y), 5.18 for Alzheimer's disease (95% CI 3.72-7.03; 7916 total p-y), and 3.35 for vascular dementia (95% CI 2.19-4.91; 7757 total p-y). DISCUSSION: Among Maracaibo Aging Study participants younger than 65 years, the incidence of dementia was higher than that of US Whites. Among individuals older than 65 years, the incidence was comparable to the mean of previous incidence estimates for other populations worldwide.


Assuntos
Envelhecimento , Demência/epidemiologia , Avaliação Geriátrica , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Apolipoproteína E4/genética , Planejamento em Saúde Comunitária , Demência/diagnóstico , Demência/genética , Feminino , Humanos , Incidência , América Latina/epidemiologia , Modelos Logísticos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
12.
Circulation ; 130(6): 466-74, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-24906822

RESUMO

BACKGROUND: Data on risk associated with 24-hour ambulatory diastolic (DBP24) versus systolic (SBP24) blood pressure are scarce. METHODS AND RESULTS: We recorded 24-hour blood pressure and health outcomes in 8341 untreated people (mean age, 50.8 years; 46.6% women) randomly recruited from 12 populations. We computed hazard ratios (HRs) using multivariable-adjusted Cox regression. Over 11.2 years (median), 927 (11.1%) participants died, 356 (4.3%) from cardiovascular causes, and 744 (8.9%) experienced a fatal or nonfatal cardiovascular event. Isolated diastolic hypertension (DBP24≥80 mm Hg) did not increase the risk of total mortality, cardiovascular mortality, or stroke (HRs≤1.54; P≥0.18), but was associated with a higher risk of fatal combined with nonfatal cardiovascular, cardiac, or coronary events (HRs≥1.75; P≤0.0054). Isolated systolic hypertension (SBP24≥130 mm Hg) and mixed diastolic plus systolic hypertension were associated with increased risks of all aforementioned end points (P≤0.0012). Below age 50, DBP24 was the main driver of risk, reaching significance for total (HR for 1-SD increase, 2.05; P=0.0039) and cardiovascular mortality (HR, 4.07; P=0.0032) and for all cardiovascular end points combined (HR, 1.74; P=0.039) with a nonsignificant contribution of SBP24 (HR≤0.92; P≥0.068); above age 50, SBP24 predicted all end points (HR≥1.19; P≤0.0002) with a nonsignificant contribution of DBP24 (0.96≤HR≤1.14; P≥0.10). The interactions of age with SBP24 and DBP24 were significant for all cardiovascular and coronary events (P≤0.043). CONCLUSIONS: The risks conferred by DBP24 and SBP24 are age dependent. DBP24 and isolated diastolic hypertension drive coronary complications below age 50, whereas above age 50 SBP24 and isolated systolic and mixed hypertension are the predominant risk factors.


Assuntos
Monitorização Ambulatorial da Pressão Arterial/métodos , Pressão Sanguínea/fisiologia , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Vigilância da População/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Seguimentos , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Resultado do Tratamento , Adulto Jovem
13.
Curr Hypertens Rep ; 16(9): 470, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25097109

RESUMO

UNLABELLED: Variability is a phenomenon attributed to most biological processes and is a particular feature of blood pressure (BP) that concerns many physicians regarding the clinical meaning and the impact on their clinical practice. In this review, we assessed the role of different indices of BP variability in cardiovascular risk stratification. We reviewed the indices of BP variability derived from ambulatory BP monitoring (day-to-night ratio, morning surge of BP, and short-term BP variability) and home BP measurement (standardized conventional BP measurement and self-BP measurement), and summarized our recent results with the intention to provide a clear message for clinical practice. CONCLUSION: BP variability, either derived from ambulatory BP measurement or home BP measurement does not substantially refine cardiovascular risk prediction over and beyond the BP level. Practitioners should be aware that BP level remains the main modifiable risk factor derived from BP measurement and contributes to improving the control of hypertension and adverse health outcomes.


Assuntos
Determinação da Pressão Arterial/métodos , Pressão Sanguínea/fisiologia , Doenças Cardiovasculares/epidemiologia , Sistema Cardiovascular/fisiopatologia , Ritmo Circadiano/fisiologia , Monitorização Ambulatorial da Pressão Arterial/métodos , Doenças Cardiovasculares/fisiopatologia , Saúde Global , Humanos , Incidência , Fatores de Risco
14.
Eur Stroke J ; 9(1): 251-258, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37873938

RESUMO

INTRODUCTION: Arterial stiffness may have a significant impact on the development of cerebral small vessel disease (cSVD). PATIENTS AND METHODS: We obtained pulse wave velocity (24-h PWV) by means of ambulatory blood pressure monitoring (ABPM) in patients with a recent small subcortical infarct (RSSI). Patients with known cardiac or arterial embolic sources were excluded. Lacunes, microbleeds, white matter hyperintensities and enlarged perivascular spaces at baseline were assessed in a brain MRI and included in a cSVD score. A follow-up MRI was obtained 2 years later and assessed for the appearance of new lacunes or microbleeds. We constructed both unadjusted and adjusted models, and subsequently selected the optimal models based on the area under the curve (AUC) of the predicted probabilities. RESULTS: Ninety-two patients (mean age 67.04 years, 69.6% men) were evaluated and 25 had new lacunes or microbleeds during follow-up. There was a strong correlation between 24-h PWV and age (r = 0.942, p < 0.001). cSVD was associated with new lacunes or microbleeds when adjusted by age, 24-h PWV, NT-proBNP and hypercholesterolemia (OR 2.453, CI95% 1.381-4.358). The models exhibiting the highest discrimination, as indicated by their area under the curve (AUC) values, were as follows: 1 (AUC 0.854) - Age, cSVD score, 24-h PWV, Hypercholesterolemia; 2 (AUC 0.852) - cSVD score, 24-h PWV, Hypercholesterolemia; and 3 (AUC 0.843) - Age, cSVD score, Hypercholesterolemia. CONCLUSIONS: cSVD score is a stronger predictor for cSVD progression than age or hemodynamic parameters in patients with a RSSI.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Hipercolesterolemia , Rigidez Vascular , Masculino , Humanos , Idoso , Adulto Jovem , Adulto , Feminino , Estudos Longitudinais , Análise de Onda de Pulso , Hipercolesterolemia/complicações , Monitorização Ambulatorial da Pressão Arterial , Doenças de Pequenos Vasos Cerebrais/complicações , Estudos de Coortes , Hemorragia Cerebral/diagnóstico por imagem
16.
Am J Hypertens ; 37(5): 323-333, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38294177

RESUMO

BACKGROUND: Evidence shows that high 24-h blood pressure (BP) variability increases cardiovascular risk. We investigated whether 24-h BP variability relates to mortality and cardiovascular risk due to inherent variability and/or hypertensive loads in 24-h BP. METHODS: A total of 1,050 participants from the Maracaibo Aging Study (mean age, 66 years; women, 67.2%) underwent 24-h ambulatory BP monitoring and were followed between 2001 and 2016. To evaluate inherent BP variability, we used average real variability (ARV) as it captures variability among consecutive BP readings. 24-h systolic BP load was the proportion (%) of systolic BP readings ≥130 mm Hg during the daytime and ≥110 during the nighttime. Our primary endpoint was total mortality and major adverse cardiovascular endpoints (MACE). Statistics included Cox proportional models. RESULTS: During a median follow-up of 8.3 years, 299 participants died and 210 experienced MACE. Each +2 mm Hg (corresponding to 1-standard deviation) higher 24-h systolic ARV (mean value, 9.0 ±â€…2.0 mm Hg) was associated with higher hazard ratios (HRs) for mortality by 1.28-fold (95% confidence interval [CI], 1.14-1.43) and for MACE by 1.24-fold (95% CI, 1.08-1.42). Each 30% higher 24-h systolic BP load (median value, 63%) was associated with mortality and MACE with HRs of 1.29 (95% CI, 1.15-1.46) and 1.28 (95% CI, 1.10-1.48); respectively. After models were additionally adjusted by BP level, only ARV was associated with mortality (HR, 1.17; 95% CI, 1.04-1.33) and MACE (HR, 1.16; 95% CI, 1.00-1.34). CONCLUSIONS: High ARV and hypertensive loads in 24-h systolic BP were associated with mortality and cardiovascular risk, however, only ARV is associated independently of the BP level.


Assuntos
Doenças Cardiovasculares , Hipertensão , Humanos , Feminino , Idoso , Pressão Sanguínea/fisiologia , Fatores de Risco , Hipertensão/complicações , Monitorização Ambulatorial da Pressão Arterial , Fatores de Risco de Doenças Cardíacas
17.
Vet World ; 16(10): 2110-2119, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38023277

RESUMO

Background and Aim: Leptospirosis is considered a neglected tropical zoonosis in low-income countries due to surveillance system limitations and non-specificity of symptoms. Humans become infected through direct contact with carrier animals or indirectly through Leptospira-contaminated environments. Conventionally, equines have been considered an uncommon source of leptospirosis, but recent publications in Latin America suggest that their role in the maintenance and dispersion of the bacteria could be more relevant than expected, as horses are susceptible to a wide variety of zoonotic Leptospira spp. from domestic and wild animals with which they share the environment. A systematic review of the published literature was conducted to compile the available information on Leptospira spp. in Ecuador, with a special focus on equine leptospirosis, to better understand the epidemiology of the bacterium and identify possible knowledge gaps. Materials and Methods: A systematic review of the published literature was conducted in PubMed, SciELO and Web of Science databases to compile the available information on Leptospira spp. in Ecuador, with a special focus on equine leptospirosis, to better understand the epidemiology of the bacterium. We used a combination of the terms (Leptospira OR Leptospirosis) AND Ecuador, without restrictions on language or publication date. Results: Our literature review reveals that published scientific information is very scarce. Eighteen full-text original scientific articles related to Leptospira or leptospirosis cases in Ecuador were included in the systematic review. Most of the studies reported data obtained from one of the four regions (Coast), and specifically from only one of the 24 Provinces of Ecuador (Manabí), which evidence a large information bias at the geographical level. Furthermore, only the studies focused on humans included clinical signs of leptospirosis and there is only one study that analyzes the presence of Leptospira spp. in water or soil as a risk factor for pathogen transmission. Finally, only one study investigated Leptospira in horses. Conclusion: Since sentinel species can provide useful data on infectious diseases when epidemiologic al information is lacking, and horses could be considered excellent sentinel species to reveal circulating serovars, we propose developing a nationwide surveillance system using horses. This cost-effective epidemiological survey method provides a baseline for implementing specific prevention and control programs in Ecuador and neighboring developing countries.

18.
Int J Surg ; 109(6): 1603-1611, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37060247

RESUMO

BACKGROUND AND AIMS: Previous studies indicated that laparoscopic surgery could improve postoperative outcomes in acute appendicitis, acute cholecystitis, perforated gastroduodenal ulcer, or acute diverticulitis, but some reported opposite results or differences in the magnitude of improvement. A contemporary analysis using propensity score matching that compares outcomes is lacking. METHODS: Over a 6-month period, 38 centres (5% of all public hospitals) attending emergency general surgery patients on a 24 h, 7 days a week basis, enroled all consecutive adult patients who underwent laparoscopic surgery or open approach. RESULTS: The study included 2 645 patients with acute appendicitis [32 years (22-51), 44.3% women], 1 182 with acute cholecystitis [65 years (48-76); 46.7% women], and 470 with gastrointestinal tract perforation [65 years (50-76); 34% women]. After propensity score matching, hospital stays decreased in acute appendicitis [open, 2 days (2-4); lap, 2 days (1-4); P <0.001], acute cholecystitis [open, 7 days (4-12); lap, 4 days (3-6); P <0.001], and gastrointestinal tract perforation [open, 11 days (7-17); lap, 6 days (5-8.5); P <0.001]. A decrease in 30-day morbidity was observed in acute appendicitis (open, 15.7%; lap, 9.7%; P <0.001), acute cholecystitis (open, 41%; lap, 21.7%; P <0.001), and gastrointestinal tract perforation (open, 45.2%; lap, 23.5%; P <0.001). A decrease in 30-day mortality was found in acute cholecystitis (open, 8.8%; lap, 2.8%; P =0.013) and gastrointestinal tract perforation (open, 10.4%; lap, 1.7%; P =0.013). CONCLUSIONS: This clinically based, multicentre study suggests that an initial laparoscopic approach could be considered not only in patients with acute appendicitis or acute cholecystitis but also in patients with a perforation of the gastrointestinal tract.


Assuntos
Apendicite , Colecistite Aguda , Laparoscopia , Humanos , Adulto , Feminino , Masculino , Estudos Prospectivos , Apendicite/cirurgia , Pontuação de Propensão , Estudos Retrospectivos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Doença Aguda , Colecistite Aguda/cirurgia , Tempo de Internação
19.
J Hum Hypertens ; 37(1): 62-67, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35013570

RESUMO

NT-proBNP is produced from both atria and ventricles and it is increased in patients with cardiac disease. NT-proBNP is also associated with cerebral small vessel disease(cSVD) but there are no studies that had carried out a systematic evaluation of cardiac function in this specific setting. We conducted a prospective observational study in 100 patients within 30 days after a recent lacunar infarct by means of brain MRI, 24 h ambulatory blood pressure monitoring, transthoracic echocardiography, and plasmatic NT-proBNP. Global cSVD burden was quantified using a validated visual score (0 to 4) and dichotomized into 2 groups (0-2 or 3-4). Age (73.8 vs 63.5 years) and NT-proBNP (156 vs 76 pg/ml) were increased in patients with SVD 3-4, while daytime augmentation index normalized for the heart rate of 75 bpm (AIx75) (22.5 vs 25.6%) was decreased. The proportion of patients with left atrial enlargement, left ventricular hypertrophy, or septal e' velocity <7 cm/s was not different between both groups. NT-proBNP was increased in patients with left atrial enlargement (126 vs 88 pg/ml). In multivariate analysis, age (OR 1.129 CI 95% 1.054-1.209), daytime AIx75 (OR 0.91 CI 95% 0.84-0.987,) and NT-proBNP (OR 1.007 CI 95% 1.001-1.012,) were independently associated with cSVD score 3-4. In conclusion, as well as in other patients with cSVD we found an association between NT-proBNP and cSVD. This association was independent of cardiac function.


Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral Lacunar , Humanos , Pessoa de Meia-Idade , Biomarcadores , Monitorização Ambulatorial da Pressão Arterial , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem , Idoso
20.
J Hypertens ; 41(11): 1785-1792, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37694533

RESUMO

BACKGROUND: Low ocular perfusion pressure (OPP), which depends on the mean arterial pressure (MAP) and intraocular pressure (IOP), is associated with glaucoma. We studied 24-h MAP dysregulations and OPP in relation to the progression of glaucoma damage. METHODS: We retrospectively analyzed 155 normal-tension glaucoma (NTG) and 110 primary open-angle glaucoma (POAG) patients aged 18 years old followed at the University Hospital Leuven with repeated visual field tests ( n  = 7000 measures, including both eyes) who underwent 24-h ambulatory blood pressure monitoring. Twenty-four-hour MAP dysregulations were variability independent of the mean (VIM), and the five lowest dips in MAP readings over 24 h. OPP was the difference between 2/3 of the MAP and IOP. Glaucoma progression was the deterioration of the visual field, expressed as decibel (dB) changes in mean deviation analyzed by applying multivariable linear mixed regression models. RESULTS: The mean age was 68 years (53% were women). High 24-h VIMmap was associated with glaucoma progression in POAG ( P  < 0.001) independently of the 24-h MAP level. The estimated changes in mean deviation in relation to dip MAP measures ranged from -2.84 dB [95% confidence interval (CI) -4.12 to -1.57] to -2.16 dB (95% CI -3.46 to -0.85) in POAG. Reduced OPP along with high variability and dips in MAP resulted in worse mean deviation deterioration. CONCLUSION: The progression of glaucoma damage associates with repetitive and extreme dips in MAP caused by high variability in MAP throughout 24 h. This progression exacerbates if 24-h MAP dysregulations occur along with reduced OPP.


Assuntos
Glaucoma de Ângulo Aberto , Humanos , Feminino , Idoso , Adolescente , Masculino , Pressão Sanguínea/fisiologia , Estudos Retrospectivos , Monitorização Ambulatorial da Pressão Arterial , Pressão Intraocular , Perfusão
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