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1.
Toxicol Appl Pharmacol ; 486: 116940, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38677602

RESUMO

L-theanine (L-THE), a non-protein amino acid isolated from Camelia sinensis, has antioxidant properties that could prevent oxidative damage and mitochondrial dysfunction generated by myocardial ischemia and reperfusion (I/R) injury. The present study aimed to identify the effects of pretreatment with L-THE in rat hearts undergoing I/R. Wistar rats received vehicle or 250 mg/Kg L-THE intragastrically for 10 days. On day 11, hearts were removed under anesthesia and exposed to I/R injury in the Langendorff system. Measurement of left ventricular developed pressure and heart rate ex vivo demonstrates that L-THE prevents I/R-induced loss of cardiac function. Consequently, the infarct size of hearts subjected to I/R was significantly decreased when L-THE was administered. L-THE also mitigated I/R-induced oxidative injury in cardiac tissue by decreasing reactive oxygen species and malondialdehyde levels, while increasing the activity of antioxidant enzymes, SOD and CAT. Additionally, L-THE prevents oxidative phosphorylation breakdown and loss of inner mitochondrial membrane potential caused by I/R, restoring oxygen consumption levels, increasing respiratory control and phosphorylation efficiency, as well as buffering calcium overload. Finally, L-THE modifies the expression of genes involved in the antioxidant response through the overexpression of SOD1, SOD2 and CAT; as well as the transcriptional factors PPARα and Nrf2 in hearts undergoing I/R. In conclusion, L-THE confers cardioprotection against I/R injury by preventing oxidative stress, protecting mitochondrial function, and promoting overexpression of antioxidant genes. More studies are needed to place L-THE at the forefront of cardiovascular research and recommend its therapeutic use.


Assuntos
Antioxidantes , Glutamatos , Mitocôndrias Cardíacas , Traumatismo por Reperfusão Miocárdica , Estresse Oxidativo , Ratos Wistar , Animais , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/patologia , Antioxidantes/farmacologia , Glutamatos/farmacologia , Masculino , Ratos , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo
2.
Trop Med Int Health ; 28(8): 641-652, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37414409

RESUMO

OBJECTIVE: To evaluate the association between Highly Active Antiretroviral Therapy (HAART) discontinuation time and therapeutic failure (TF) in Venezuelan immigrants with HIV that restart HAART. METHODS: We carried out a retrospective cohort study in a large hospital in Peru. We included Venezuelan immigrants who restarted HAART and were followed over at least 6 months. The primary outcome was TF. Secondary outcomes were immunologic (IF), virologic (VF) and clinical (CF) failures. The exposure variable was HAART discontinuation, categorised as no discontinuation, less than 6 months, and 6 months or more. We applied generalised linear models Poisson family with robust standard errors to calculate crude (cRR) and adjusted (aRR) relative risks by statistical and epidemiological criteria. RESULTS: We included 294 patients, 97.2% were males, and the median age was 32 years. Out of all the patients, 32.7% discontinued HAART for less than 6 months, 15.0% discontinued for more than 6 months and the remaining 52.3% did not discontinue. The cumulative incidence of TF was 27.9%, 24.5% in VF, 6.0% in IF and 6.0% in CF. Compared with non-discontinued HAART patients, the discontinuation for less than 6 months (aRR = 1.98 [95% CI: 1.27-3.09]) and from 6 months to more (aRR = 3.17 [95% CI: 2.02-4.95]) increased the risk of TF. Likewise, treatment discontinuation of up to 6 months (aRR = 2.32 [95% CI: 1.40-3.84]) and from 6 months to more (aRR = 3.93 [95% CI: 2.39-6.45]) increased the risk of VF. CONCLUSIONS: HAART discontinuation increases the probability of TF and VF in Venezuelan immigrants.


Assuntos
Fármacos Anti-HIV , Emigrantes e Imigrantes , Infecções por HIV , Masculino , Humanos , Adulto , Feminino , Terapia Antirretroviral de Alta Atividade , HIV , Estudos de Coortes , Peru/epidemiologia , Fármacos Anti-HIV/uso terapêutico , Estudos Retrospectivos , Infecções por HIV/epidemiologia , Hospitais , Contagem de Linfócito CD4 , Carga Viral
3.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208750

RESUMO

Entamoeba histolytica (protozoan; family Endomoebidae) is the cause of amoebiasis, a disease related to high morbidity and mortality. Nowadays, this illness is considered a significant public health issue in developing countries. In addition, parasite resistance to conventional medicinal treatment has increased in recent years. Traditional medicine around the world represents a valuable source of alternative treatment for many parasite diseases. In a previous paper, we communicated about the antiprotozoal activity in vitro of the methanolic (MeOH) extract of Ruta chalepensis (Rutaceae) against E. histolytica. The plant is extensively employed in Mexican traditional medicine. The following workup of the MeOH extract of R. chalepensis afforded the furocoumarins rutamarin (1) and chalepin (2), which showed high antiprotozoal activity on Entamoeba histolytica trophozoites employing in vitro tests (IC50 values of 6.52 and 28.95 µg/mL, respectively). Therefore, we offer a full scientific report about the bioguided isolation and the amebicide activity of chalepin and rutamarin.


Assuntos
Furocumarinas/isolamento & purificação , Ruta/metabolismo , Amebicidas/isolamento & purificação , Amebicidas/farmacologia , Antiprotozoários/farmacologia , Benzopiranos/metabolismo , Entamoeba histolytica/efeitos dos fármacos , Entamoeba histolytica/patogenicidade , Furocumarinas/farmacologia , Concentração Inibidora 50 , Medicina Tradicional , México , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia
4.
Molecules ; 19(12): 21044-65, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25517343

RESUMO

Amoebiasis caused by Entamoeba histolytica is associated with high morbidity and mortality is becoming a major public health problem worldwide, especially in developing countries. Because of the side-effects and the resistance that pathogenic protozoa build against the standard antiparasitic drugs, e.g., metronidazole, much recent attention has been paid to plants used in traditional medicine around the world in order to find new antiprotozoal agents. We collected 32 plants used in Northeast Mexican traditional medicine and the methanolic extracts of these species were screened for antiprotozoal activity against E. histolytica trophozoites using in vitro tests. Only 18 extracts showed a significant inhibiting activity and among them six plant extracts showed more than 80% growth inhibition against E. histolytica at a concentration of 150 µg/mL and the IC50 values of these extracts were determined. Lippia graveolens Kunth and Ruta chalepensis Pers. showed the more significant antiprotozoal activity (91.54% and 90.50% growth inhibition at a concentration of 150 µg/mL with IC50 values of 59.14 and 60.07 µg/mL, respectively). Bioassay-guided fractionation of the methanolic extracts from these two plants afforded carvacrol (1) and chalepensin (2), respectively, as bioactive compounds with antiprotozoal activity.


Assuntos
Amebicidas/farmacologia , Entamoeba histolytica/efeitos dos fármacos , Lippia/química , Extratos Vegetais/farmacologia , Ruta/química , Amebicidas/isolamento & purificação , Cimenos , Avaliação Pré-Clínica de Medicamentos , Furocumarinas/isolamento & purificação , Furocumarinas/farmacologia , Concentração Inibidora 50 , Medicina Tradicional , México , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Extratos Vegetais/isolamento & purificação
5.
Plants (Basel) ; 13(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38794444

RESUMO

Argemone mexicana L. has been used in traditional Mexican medicine. Among its bioactive constituents, berberine (BER) has garnered attention for its cytotoxic properties against different tumor cell lines. This study investigates the in vitro toxicity against HEP-G2 (human hepatocellular carcinoma) and murine lymphoma (L5178Y-R) cells using the MTT assay of the methanol extract (AmexM), sub-partitions of A. mexicana, and BER. Selectivity indices (SIs) were determined by comparing their cytotoxic effects on VERO (monkey kidney epithelial) and PBMC (human peripheral blood mononuclear) non-tumoral cells. Additionally, the anti-hemolytic effect of these treatments was assessed using the AAPH method. The treatment with the most promising activity against tumor cells and anti-hemolytic efficacy underwent further evaluation for toxicity in Artemia salina and antioxidant activities using DPPH, ABTS, and FRAP assays. BER demonstrated an IC50 = 56.86 µg/mL in HEP-G2 cells and IC50 < 5.0 µg/mL in L5178Y-R cells, with SI values of 15.97 and >5.40 in VERO and PBMC cells, respectively. No significant hemolytic effects were observed, although AmexM and BER exhibited the highest anti-hemolytic activity. BER also demonstrated superior antioxidant efficacy, with lower toxicity in A. salina nauplii compared to the control. Additionally, BER significantly attenuated nitric oxide production. This study highlights the antiproliferative effects of A. mexicana, particularly BER, against HEP-G2 and L5178Y-R tumor cell lines, along with its selectivity towards normal cells. Furthermore, its anti-hemolytic and antioxidant potentials were demonstrated, suggesting that BER is a promising candidate for potent chemotherapeutic agents.

6.
Biomed Signal Process Control ; 85: 104905, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36993838

RESUMO

Purpose: A semi-supervised two-step methodology is proposed to obtain a volumetric estimation of COVID-19-related lesions on Computed Tomography (CT) images. Methods: First, damaged tissue was segmented from CT images using a probabilistic active contours approach. Second, lung parenchyma was extracted using a previously trained U-Net. Finally, volumetric estimation of COVID-19 lesions was calculated considering the lung parenchyma masks.Our approach was validated using a publicly available dataset containing 20 CT COVID-19 images previously labeled and manually segmented. Then, it was applied to 295 COVID-19 patients CT scans admitted to an intensive care unit. We compared the lesion estimation between deceased and survived patients for high and low-resolution images. Results: A comparable median Dice similarity coefficient of 0.66 for the 20 validation images was achieved. For the 295 images dataset, results show a significant difference in lesion percentages between deceased and survived patients, with a p-value of 9.1 × 10-4 in low-resolution and 5.1 × 10-5 in high-resolution images. Furthermore, the difference in lesion percentages between high and low-resolution images was 10 % on average. Conclusion: The proposed approach could help estimate the lesion size caused by COVID-19 in CT images and may be considered an alternative to getting a volumetric segmentation for this novel disease without the requirement of large amounts of COVID-19 labeled data to train an artificial intelligence algorithm. The low variation between the estimated percentage of lesions in high and low-resolution CT images suggests that the proposed approach is robust, and it may provide valuable information to differentiate between survived and deceased patients.

7.
Plants (Basel) ; 12(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37299182

RESUMO

Ruta chalepensis is an herb used to treat various ailments, and its potential cytotoxic effects on different tumor cell lines have been extensively studied. The present study aimed to evaluate the cytotoxic activity of R. chalepensis methanol extract (RCME), sub-partitions obtained from solvents of increasing polarity, and major compounds, as well as their hemolytic, anti-hemolytic, and antioxidant potential. The in vitro cytotoxic activity against the human hepatocarcinoma (HEP-G2) and the murine lymphoma cell line (L5178Y-R) was evaluated using the colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay, whereas selectivity indices (SIs) were determined by comparing cytotoxicity against normal African green monkey kidney cells (VERO) and human peripheral blood mononuclear cells (PBMC). Hemolytic and anti-hemolytic activities were evaluated on human erythrocytes. The most effective cytotoxic treatment was evaluated for nitric oxide release by J774A.1 macrophages. Antioxidant activity of R. chalepensis material was also determined. Results showed that RCME produced significant (p < 0.05) cytotoxicity in HEP-G2 (IC50 = 1.79 µg/mL) and L5178Y-R (IC50 = 1.60 µg/mL) cells and exhibited high SIs (291.50 and 114.80, respectively). In addition, the n-hexane fraction (RCHF) showed an IC50 of 18.31 µg/mL in HEP-G2 cells and an SI of 9.48 in VERO cells, whereas the chloroform fraction (RCCF) evidenced an IC50 of 1.60 µg/mL in L5178Y-R cells and an SI of 34.27 in PBMC cells. Chalepensin (CHL), rutamarin (RTM), and graveolin (GRV), which are major components of R. chalepensis, showed high activity against L5178Y-R cells, with IC50 of 9.15, 15.13 and SI of 45.08 µg/mL, respectively. In addition, CHL, RTM, and GRV showed SIs of 24.76, 9.98, and 3.52, respectively, when compared with PBMC cells. RCME at concentrations of 125 µg/mL and 250 µg/mL, significantly (p < 0.05) decreased nitrite production in J774A.1 cells, when exposed to lipopolysaccharide. This study demonstrated that RCME showed significant cytotoxic activity against HEP-G2 and L5178Y-R cells, without affecting normal VERO, PBMC, and J774A.1 cells.

8.
Artigo em Inglês | MEDLINE | ID: mdl-34891245

RESUMO

Heart rate variability (HRV) has been extensively investigated as a noninvasive marker to evaluate the functionality of the autonomic nervous system (ANS). Many studies have provided photoplethysmography (PPG) as a surrogate for electrocardiogram (ECG) signal HRV measurements. Remote PPG (rPPG) has been also investigated for pulse rate variability (PRV) estimation but in controlled conditions. We remotely extracted PRV using a smartphone camera for subjects in static and lateral motion while their respiratory rate was set to three breathing rates in an indoor illumination environment. PRV was compared with ECG-based HRV as a gold standard. We tested our algorithms on five healthy subjects. The results showed high correlation for rPPG-based HRV by presenting means of standard deviation of normal-to-normal intervals (SDNN) and root mean square of successive heartbeat interval differences (RMSSD) correlation coefficient greater than 0.95 in rest and greater than 0.87 in motion. The error of mean low frequency over high frequency (LF/HF) ratio estimated from PRV was 0.13 in rest and 0.25 in lateral motion. Moreover, a statistically significant correlation was obtained between HRV and PRV power spectra and temporal signals for all performed tasks. The obtained results contributed to confirm that remote imaging measurement of cardiac parameters is a promising, convenient, and low-cost alternative to specialized biomedical sensors in a diversity of relevant experimental maneuver.


Assuntos
Taxa Respiratória , Smartphone , Eletrocardiografia , Frequência Cardíaca , Humanos , Fotopletismografia
9.
IEEE J Biomed Health Inform ; 25(2): 602-612, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32750916

RESUMO

As a reliable indicator for individual's healthiness conditions, heart rate (HR) has been widely considered and used. Imaging photoplethysmography (iPPG) is recently highlighted as a promising HR measurement method, due to its non-contact characteristics, by extracting the HR from facial video recordings. In this study, we propose a camera-based HR monitoring technique that estimates HR information from iPPG signals extracted from a video sequence. Videos were recorded using a smartphone or a laptop camera. We adopted the plane-orthogonal-to-skin (POS) method to compute iPPG. The proposed method is evaluated by applying it to extract HR of 9 subjects at rest and during two motion conditions (lateral and frontal) while they were performing several respiratory maneuvers-spontaneous, metronome, and forced. Automatic face detection algorithms were implemented in the proposed method. Our experimental results show that mean values of HR have 0.56% error and 99.4% accuracy when compared to HR calculated from the gold-standard electrocardiography (ECG) reference in diverse conditions of motions and respiratory maneuvers.


Assuntos
Fotopletismografia , Smartphone , Algoritmos , Frequência Cardíaca , Humanos , Monitorização Fisiológica
10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 1957-1960, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891670

RESUMO

Blind linear unmixing (BLU) methods allow the separation of multi and hyperspectral data into end-members and abundance maps in an unsupervised fashion. However, due to incident noise, the abundance maps can exhibit high presence of granularity. To address this problem, in this paper, we present a novel proposal for BLU that considers spatial coherence in the abundance estimations, through a total spatial variation component. The proposed BLU formulation is based on the blind end-member and abundance extraction perspective with total spatial variation (EBEAE-STV). In EBEAE-STV, internal abundances are added to incorporate the spatial coherence in the cost function, which is solved by a coordinates descent algorithm. The results with synthetic data show that the proposed algorithm can significantly decrease the granularity in the estimated abundances, and the estimation errors and computational times are lower compared to state of the art methodologies.Clinical relevance- The proper and robust estimation of end-members and their respective contributions (abundances) in multi-spectral and hyper-spectral images from the proposed EBEAE-STV methodology might provide useful information in several biomedical applications, such as chemometric analysis on different biological samples, tumor identification and brain tissue classification for hyper-spectral imaging, among others.


Assuntos
Quimiometria , Imageamento Hiperespectral , Algoritmos , Diagnóstico por Imagem
11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 7320-7323, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892788

RESUMO

Parkinsonian Tremor (PT) is the most common symptom of Parkinson's disease. Its early detection plays an important role in the diagnosis of the disease as it is often mistaken for another type of tremor, called Essential Tremor (ET). Accelerometry analysis has proven to be a trustworthy method for determining the frequency, amplitude, and occurrence of tremor. In addition, the use of portable and wearable sensors has increased due to the rapid growth of Internet of Things (IoT) technology, allowing data to be collected, processed, stored, and transmitted. In this paper, a wearable system consisting of a digital 3-axis accelerometer ADXL345 and micro-controller unit ESP32 was implemented to transmit accelerometry (ACC) signals from each upper limb simultaneously to a Graphical User Interface (GUI), that was developed in Python as an MQTT client, allowing the user to visualize both real-time and offline signals as well as to add markers to indicate events during the acquisition. Furthermore, this GUI is capable of performing an offline analysis consisting of the computing of Power Spectral Density (PSD) using Welch's method and a Spectrogram to visualize a time-frequency distribution of the ACC signals.


Assuntos
Tremor Essencial , Doença de Parkinson , Acelerometria , Humanos , Doença de Parkinson/diagnóstico , Tremor/diagnóstico , Extremidade Superior
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 3850-3853, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892074

RESUMO

A two-step method for obtaining a volumetric estimation of COVID-19 related lesion from CT images is proposed. The first step consists in applying a U-NET convolutional neural network to provide a segmentation of the lung-parenchyma. This architecture is trained and validated using the Thoracic Volume and Pleural Effusion Segmentations in Diseased Lungs for Benchmarking Chest CT Processing Pipelines (PleThora) dataset, which is publicly available. The second step consists in obtaining the volumetric lesion estimation using an automatic algorithm based on a probabilistic active contour (PACO) region delimitation approach. Our pipeline successfully segmented COVID-19 related lesions in CT images, with exception of some mislabeled regions including lung airways and vasculature. Our workflow was applied to images in a cohort of 50 patients.


Assuntos
COVID-19 , Humanos , Pulmão/diagnóstico por imagem , Redes Neurais de Computação , SARS-CoV-2 , Tomografia Computadorizada por Raios X
13.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 7625-7628, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892855

RESUMO

The Biomedical Engineering (BME) bachelor pro-gram of the Faculty of Sciences in Universidad Autónoma de San Luis Potosí (UASLP) was created in June of 2010, with the aim of training professionals with an integral perspective in the engineering field by considering a multidisciplinary approach to develop and apply technology in the areas of medicine and biology. After 10 years, our BME program has achieved national recognition. Despite of being an emerging program, this achievement has been obtained by the consolidation of our academic staff, the outstanding participation of our students in national and international academic events, and the historical graduation results. In our comprehensive evaluation, we report an overall terminal efficiency (completion rate) of 67% and a graduation rate of 47.2%, where these values are above the average for an engineering program in our institution. Additionally, the BME program provides students with solid skills and background to carry out research activities, which has resulted in a considerable number of alumni pursuing graduate studies or have already completed one. Our results show that 90% of our former students are working after graduation, but only 44% work in the field of biomedical engineering, since the regional labor market starts to saturate given the fact that, at present, students from six generations have completed our BME bachelor program. In this way, few graduates visualize the wide spectrum of job options where a biomedical engineer can impact, by their distinctive comprehensive and multidisciplinary training. Therefore, it is necessary to propose new curricular design strategies to provide our students with an academic training that allows them to enter a globalized world, where there is an even greater spectrum of engineering possibilities related to the fields of medicine and biology, in line with current trends.


Assuntos
Engenharia Biomédica , Universidades , Bioengenharia , Engenharia Biomédica/educação , Humanos , Estudantes
14.
Plants (Basel) ; 10(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34579443

RESUMO

The genus Zingiberaceae has been widely used for phytotherapeutic purposes in traditional medicine throughout the world for its anti-inflammatory activity. Experimental studies have established that inflammation caused by chronic infections represents a risk factor for different forms of cancer. The objective of this study was focused on determining the anti-inflammatory capacity and cytotoxic activity of aqueous extracts of Elettaria cardamomum (cardamom) and Curcuma Longa (turmeric). The extracts were obtained by maceration and, through GC-MS/MS, a total of 11 different chemical components were determined in the aqueous extract of cardamom and 7 in the extract of turmeric. The main compounds found in cardamom and turmeric were α-terpinyl acetate (54.46%) and ß-turmerone (33.45%), respectively. RT-qPCR results showed significantly lower gene expression levels of innate inflammatory cytokines (IL-6 and TNF-α) compared to the control (LPS). Also, it was observed that the extracts do not possess cytotoxic activity against different cell lines, where E. cardamomum showed EC50 (µg/mL) of 473.84 (HeLa cells), 237.36 (J774A.1 cells), 257.51 (Vero E6 cells), and 431.16 (Balb/C peritoneal cells) and C. longa showed EC50 (µg/mL) of 351.17 (HeLa cells), 430.96 (J774A.1 cells), 396.24 (Vero E6 cells), and 362.86 (Balb/C peritoneal cells). The results of this research suggest that natural extracts of E. cardamomum and C. longa possess anti-inflammatory effects and no cytotoxic activity against HeLa, J774A.1, Vero E6, and Balb/C peritoneal cell lines. Finally, it was observed that the extracts also decreased nitric oxide (NO) production in peritoneal macrophages.

15.
PLoS One ; 16(3): e0248301, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33735228

RESUMO

The deconvolution process is a key step for quantitative evaluation of fluorescence lifetime imaging microscopy (FLIM) samples. By this process, the fluorescence impulse responses (FluoIRs) of the sample are decoupled from the instrument response (InstR). In blind deconvolution estimation (BDE), the FluoIRs and InstR are jointly extracted from a dataset with minimal a priori information. In this work, two BDE algorithms are introduced based on linear combinations of multi-exponential functions to model each FluoIR in the sample. For both schemes, the InstR is assumed with a free-form and a sparse structure. The local perspective of the BDE methodology assumes that the characteristic parameters of the exponential functions (time constants and scaling coefficients) are estimated based on a single spatial point of the dataset. On the other hand, the same exponential functions are used in the whole dataset in the global perspective, and just the scaling coefficients are updated for each spatial point. A least squares formulation is considered for both BDE algorithms. To overcome the nonlinear interaction in the decision variables, an alternating least squares (ALS) methodology iteratively solves both estimation problems based on non-negative and constrained optimizations. The validation stage considered first synthetic datasets at different noise types and levels, and a comparison with the standard deconvolution techniques with a multi-exponential model for FLIM measurements, as well as, with two BDE methodologies in the state of the art: Laguerre basis, and exponentials library. For the experimental evaluation, fluorescent dyes and oral tissue samples were considered. Our results show that local and global perspectives are consistent with the standard deconvolution techniques, and they reached the fastest convergence responses among the BDE algorithms with the best compromise in FluoIRs and InstR estimation errors.


Assuntos
Corantes Fluorescentes/química , Processamento de Imagem Assistida por Computador/métodos , Modelos Químicos , Algoritmos , Conjuntos de Dados como Assunto , Humanos , Análise dos Mínimos Quadrados , Microscopia de Fluorescência , Mucosa Bucal/patologia , Neoplasias Bucais/patologia , Fatores de Tempo
16.
Rev Chilena Infectol ; 37(6): 750-755, 2020 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-33844816

RESUMO

BACKGROUND: Tuberculosis (TB) is one of the ten leading causes of death worldwide. AIM: To characterize the clinical and epidemiological point of view of TB cases reported in the Department of Caaguazú-Paraguay, from 2014 to 2017. METHODS: Observational, descriptive, retrospective study; Population: 659 cases of TB registered in the National Tuberculosis Control Program (NTCP); variables: age, sex, population group, type of TB, TB/HIV coinfection. We procesed database in Excel 2016 © using Stata 14.0®. RESULTS: 63.3% were of male gender, average age: 35.8 years, 39.6% were indigenous and 85.4% were liberty deprived persons known as inmates (LDP), 89.6% had pulmonary TB and 2,4% had TB/HIV coinfection. Incidence rate exceed 21.6/100,000 inhabitants in 2014. Indigenous incidence was 76.5/100,000 inhabitants in 2017, LDP incidence was 2,272.1/ 100,000 inhabitants in 2017. CONCLUSION: The incidence of TB in the Department of Caaguazú is low, mainly affecting men, while TB incidence in indigenous people and LDP was high.


Assuntos
Coinfecção , Infecções por HIV , Tuberculose Pulmonar , Tuberculose , Adulto , Coinfecção/epidemiologia , Infecções por HIV/epidemiologia , Humanos , Incidência , Masculino , Paraguai/epidemiologia , Estudos Retrospectivos , Tuberculose/epidemiologia
17.
Med Biol Eng Comput ; 57(3): 565-576, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30267254

RESUMO

In medical imaging, the availability of robust and accurate automatic segmentation methods is very important for a user-independent and time-saving delineation of regions of interest. In this work, we present a new variational formulation for multiclass image segmentation based on active contours and probability density functions demonstrating that the method is fast, accurate, and effective for MRI brain image segmentation. We define an energy function assuming that the regions to segment are independent. The first term of this function measures how much the pixels belong to each class and forces the regions to be disjoint. In order for this term to be outlier-resistant, probability density functions were used allowing to define the structures to be segmented. The second one is the classical regularization term which constrains the border length of each region removing inhomogeneities and noise. Experiments with synthetic and real images showed that this approach is robust to noise and presents an accuracy comparable to other classical segmentation approaches (in average DICE coefficient over 90% and ASD below one pixel), with further advantages related to segmentation speed. Graphical Abstract.


Assuntos
Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Líquido Cefalorraquidiano/diagnóstico por imagem , Humanos , Probabilidade
18.
An. Fac. Cienc. Méd. (Asunción) ; 56(2): 27-34, 20230801.
Artigo em Espanhol | LILACS | ID: biblio-1444955

RESUMO

Introducción: El maltrato es una problemática que el mundo viene sufriendo y sosteniendo desde siglos anteriores y el sector salud no queda exento de tal agravio. En Latinoamérica existe un alto índice de maltratos en médicos. Objetivos: Determinar la percepción sobre el maltrato en médicos residentes de un hospital de referencia nacional de Paraguay durante el 2020. Materiales y métodos: Se realizó un estudio observacional, descriptivo de corte transversal, dónde fueron incluidos 240 residentes de las diferentes especialidades de un hospital de referencia nacional. Resultados: Ingresaron al estudio 240 médicos residentes, con una edad promedio de 27,3 ±1,6. El 52,08% (125) fueron del sexo masculino. En cuanto al maltrato psicológico, el 98,33% (236) recibió críticas o humillaciones, el 92,08% (221) ha sido víctima de gritos y el 39% (94) de guardia como castigo. Lo que respecta al maltrato físico, el 9% (22) de los residentes recibió golpes o empujones. El 7,92% (19) refirió haber recibido comentarios sexuales sobre su cuerpo o parte de él y el 2% (5) haber sido expuesto a material pornográfico, evidenciando el maltrato de índole sexual. En relación al perpetrador del total de episodios de maltrato que corresponde al 56,78% (494), el Residente Superior ha sido señalado como principal autor. Conclusión: Existe una alarmante frecuencia de maltrato en la formación profesional de los médicos residentes. Se destaca el maltrato psicológico en mayor proporción y al Residente Superior como principal perpetrador.


Introduction: Abuse is a problem that the world has been suffering and sustaining for centuries and the health sector is not exempt from such injury. In Latin America there is a high rate of mistreatment in doctors. Objectives: To determine the perception of mistreatment in resident doctors of a national reference hospital in Paraguay during 2020. Materials and methods: Cross-sectional study was carried out, where 240 residents of the different specialties of a national referral hospital were included. Results: 240 residents entered the study, with a mean age of 27.3 ± 1.6. 52.08% (125) were male. Regarding psychological abuse, 98.33% (236) received criticism or humiliation, 92.08% (221) have been the victim of shouting and 39% (94) on duty as punishment. Regarding physical abuse, 9% (22) of the residents received blows or shoves. 7.92% (19) reported having received sexual comments about their body or part of it and 2% (5) having been exposed to pornographic material, evidencing abuse of a sexual nature. In relation to the perpetrator of the total abuse episodes, which corresponds to 48.85% (594), the Senior Resident has been identified as the main author. Conclusion: There is an alarming frequency of abuse in the professional training of resident doctors. Psychological abuse stands out in a greater proportion and the Senior Resident as the main perpetrator.

19.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1447182

RESUMO

Introducción: El maltrato es una problemática que el mundo viene sufriendo y sosteniendo desde siglos anteriores y el sector salud no queda exento de tal agravio. En Latinoamérica existe un alto índice de maltratos en médicos. Objetivos: Determinar la percepción sobre el maltrato en médicos residentes de un hospital de referencia nacional de Paraguay durante el 2020. Materiales y métodos: Se realizó un estudio observacional, descriptivo de corte transversal, dónde fueron incluidos 240 residentes de las diferentes especialidades de un hospital de referencia nacional. Resultados: Ingresaron al estudio 240 médicos residentes, con una edad promedio de 27,3 ±1,6. El 52,08% (125) fueron del sexo masculino. En cuanto al maltrato psicológico, el 98,33% (236) recibió críticas o humillaciones, el 92,08% (221) ha sido víctima de gritos y el 39% (94) de guardia como castigo. Lo que respecta al maltrato físico, el 9% (22) de los residentes recibió golpes o empujones. El 7,92% (19) refirió haber recibido comentarios sexuales sobre su cuerpo o parte de él y el 2% (5) haber sido expuesto a material pornográfico, evidenciando el maltrato de índole sexual. En relación al perpetrador del total de episodios de maltrato que corresponde al 56,78% (494), el Residente Superior ha sido señalado como principal autor. Conclusión: Existe una alarmante frecuencia de maltrato en la formación profesional de los médicos residentes. Se destaca el maltrato psicológico en mayor proporción y al Residente Superior como principal perpetrador.


Introduction: Abuse is a problem that the world has been suffering and sustaining for centuries and the health sector is not exempt from such injury. In Latin America there is a high rate of mistreatment in doctors. Objectives: To determine the perception of mistreatment in resident doctors of a national reference hospital in Paraguay during 2020. Materials and methods: Cross-sectional study was carried out, where 240 residents of the different specialties of a national referral hospital were included. Results: 240 residents entered the study, with a mean age of 27.3 ± 1.6. 52.08% (125) were male. Regarding psychological abuse, 98.33% (236) received criticism or humiliation, 92.08% (221) have been the victim of shouting and 39% (94) on duty as punishment. Regarding physical abuse, 9% (22) of the residents received blows or shoves. 7.92% (19) reported having received sexual comments about their body or part of it and 2% (5) having been exposed to pornographic material, evidencing abuse of a sexual nature. In relation to the perpetrator of the total abuse episodes, which corresponds to 48.85% (594), the Senior Resident has been identified as the main author. Conclusion: There is an alarming frequency of abuse in the professional training of resident doctors. Psychological abuse stands out in a greater proportion and the Senior Resident as the main perpetrator.

20.
Rev Chilena Infectol ; 35(1): 41-48, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-29652971

RESUMO

Background The main cause of death in HIV patients is tuberculosis (TB). However, few Latin American studies have evaluated the prognosis of patients with coinfection. Aim To determine the factors associated with survival in patients with HIV-TB coinfection treated at a Peruvian referral hospital. Methods A retrospective cohort study was performed based on clinical records of patients treated at the Department of Infectious Diseases in the Arzobispo Loayza National Hospital from 2004 to 2012. Survival was assessed using the Kaplan-Meier estimator and Cox Proportional Hazard Model. Results From 315 patients, 82 died during the follow-up. The mean of follow for each patient was 730 days. The multivariate analysis showed that receiving HAART (HR: 0,31; IC: 0,20-0,50; p < 0,01) and having more weight (HR: 0,96; IC 0,94-0,98; p < 0,01) when the coinfection was diagnosed, were protective factors; while having a pathology different from TB (HR: 1,88; IC: 1,19-2,98; p < 0,01), age in years (HR: 1,76; IC: 1,12-2,74; p ≤ 0,01) and being hospitalized when diagnosed with TB (HR: 1,69; IC 1,02-2,80; p < 0,04) were associated with lower survival. Discussion Receiving HAART and having more weight when the coinfection is diagnosed were associated with a higher chance of survival.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Coinfecção/mortalidade , Tuberculose/mortalidade , Tuberculose/virologia , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Adulto , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Coinfecção/tratamento farmacológico , Feminino , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Peru/epidemiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Tuberculose/tratamento farmacológico , Carga Viral
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