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1.
J. Health Biol. Sci. (Online) ; 12(1): 1-4, jan.-dez. 2024. ilus
Artículo en Inglés | LILACS | ID: biblio-1554327

RESUMEN

Introduction: Segmental and Focal Glomerulosclerosis (FSGS) is an entity characterized by glomerular damage involving the podocyte as the main target. A variant with a worse prognosis, poor response to corticosteroid therapy, and rapid progression to end-stage renal disease is recognized as collapsing FSGS. Case Report: A 102-year-old man with nephrotic syndrome and acute kidney injury underwent renal biopsy, revealing collapsing FSGS. He achieved an excellent response to immunosuppressive treatment, presenting renal recovery, and was discharged from dialysis treatment. Discussion: Diagnosis and definition of treatment in the elderly are challenging, and each case must be individualized and have functionality and risk assessed in a naturally immunosuppressed population.


Introdução: Glomeruloesclerose Segmentar e Focal (GESF) é uma entidade caracterizada por lesão glomerular que envolve o podócito como principal alvo. Uma variante de pior prognóstico, baixa resposta à corticoterapia, e rápida evolução para doença renal terminal é reconhecida como GESF colapsante. Relato de Caso: Um homem de 102 anos com síndrome nefrótica e lesão renal aguda foi submetido a biópsia renal, revelando GESF colapsante. Ele obteve excelente resposta ao tratamento imunossupressor, apresentando recuperação renal e recebendo alta de terapia renal substitutiva. Discussão: Diagnóstico e definição de tratamento nos idosos são desafiadores, devendo-se individualizar cada caso, avaliar funcionalidade e risco em uma população naturalmente imunossupressa.


Asunto(s)
Humanos , Masculino , Anciano de 80 o más Años , Anciano , Anciano Frágil , Glomerulonefritis , Fallo Renal Crónico , Síndrome Nefrótico
2.
J. Health Biol. Sci. (Online) ; 12(1): 1-4, jan.-dez. 2024. ilus
Artículo en Inglés | LILACS | ID: biblio-1551179

RESUMEN

The compound "ADE" is an injectable oil for veterinary use which contains large amounts of vitamins A, D and E. The parenteral application in humans leads to a granuloma reaction which triggers hypercalcemia. A 42-year-old man was admitted with lower limb pain, nephrolithiasis and nephrocalcinosis. Laboratory tests revealed creatinine 4.59 mg/dl, calcium 13.3 mg/dl and parathormone 13.8 pg/ml. He underwent an ureterolithotripsy, stent placement, intravenous crystalloid fluids, and corticosteroid. He improved symptoms, kidney function and normalized serum calcium. The "ADE"-induced hypercalcemia diagnosis can be challenging. The early diagnosis may avoid negative outcomes.


O composto "ADE'' é um óleo veterinário injetável que contém grandes quantidades de vitaminas A, D e E. A aplicação parenteral causa reação granulomatosa e hipercalcemia. Um homem de 42 anos foi admitido com dor no membro inferior, nódulos musculares endurecidos, nefrolitíase e nefrocalcinose. O laboratório revelou creatinina 4,59 mg/dl, cálcio 13,3 mg/dl e paratormônio 13,8 pg/ml. Foi tratado com ureterolitotripsia, cateter duplo-J, cristaloide intravenoso e corticoterapia. Ele apresentou melhora dos sintomas, função renal e normalizou cálcio. O diagnóstico da hipercalcemia pelo "ADE'' pode ser desafiador. O diagnóstico precoce pode evitar desfechos negativos.


Asunto(s)
Humanos , Masculino , Adulto , Lesión Renal Aguda , Hipercalcemia , Nefrolitiasis , Nefrocalcinosis
3.
Parasit Vectors ; 16(1): 391, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891604

RESUMEN

BACKGROUND: The tick Amblyomma cajennense sensu stricto (A. cajennense s.s.) frequently parasitizes animals and humans in the Amazon biome, in addition to being a vector of Rickettsia amblyommatis. In the present study, we evaluated both the population dynamics of A. cajennense s.s. in a degraded area of the Amazon biome and the presence of rickettsial organisms in this tick population. METHODS: The study was carried out in a rural area of the Santa Inês municipality (altitude: 24 m a.s.l.), Maranhão state, Brazil. Ticks were collected from the environment for 24 consecutive months, from June 2021 to May 2023. The region is characterized by two warm seasons: a rainy season (November-May) and a dry season (June-October). We characterized the temporal activity of A. cajennense s.s. on the vegetation by examining questing activity for each life stage (larvae, nymphs, adults [males and females]) in relation to the dry and rainy season. Ticks collected in this study were randomly selected and individually tested by a TaqMan real-time PCR assay that targeted a 147-bp fragment of the rickettsial gltA gene. RESULTS: Overall, 1843 (62.4%) adults (52.6% females, 47.4% males), 1110 (37.6%) nymphs and 398 larval clusters were collected. All adult females and nymphs were morphologically identified as A. cajennense s.s. Larval activity was observed from April to December, with a peak from June to September (dry season); nymph abundance peaked from September to November (transition period between dry and rainy seasons); and adult ticks were abundant from October to May (spring/summer/early autumn). The infection rate by R. amblyommatis in A. cajennense s.s. ticks was at least 7% (7/99). CONCLUSION: Our data suggest a 1-year generation pattern for A. cajennense s.s., with a well-defined seasonality of larvae, nymphs and adults in the Amazon biome. Larvae predominate during the dry season, nymphs are most abundant in the dry-rainy season transition and adults are most abundant in the rainy season. The presence of R. amblyommatis in adult ticks suggests that animals and humans in the study region are at risk of infection by this species belonging to the spotted fever group of Rickettsia.


Asunto(s)
Ixodidae , Infecciones por Rickettsia , Rickettsia , Garrapatas , Animales , Humanos , Masculino , Femenino , Estaciones del Año , Amblyomma , Rickettsia/genética , Infecciones por Rickettsia/epidemiología , Infecciones por Rickettsia/microbiología , Garrapatas/microbiología , Brasil/epidemiología , Ninfa/microbiología , Larva/microbiología , Ecosistema
4.
Sci Rep ; 13(1): 9280, 2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37286659

RESUMEN

Results of measurements on the thermoelectric power of 45 nm diameter interconnected nanowire networks consisting of pure Fe, dilute FeCu and FeCr alloys and Fe/Cu multilayers are presented. The thermopower values of Fe nanowires are very close to those found in bulk materials, at all temperatures studied between 70 and 320 K. For pure Fe, the diffusion thermopower at room temperature, estimated to be around - 15 [Formula: see text]V/K from our data, is largely supplanted by the estimated positive magnon-drag contribution, close to 30 [Formula: see text]V/K. In dilute FeCu and FeCr alloys, the magnon-drag thermopower is found to decrease with increasing impurity concentration to about 10 [Formula: see text]V/K at 10[Formula: see text] impurity content. While the diffusion thermopower is almost unchanged in FeCu nanowire networks compared to pure Fe, it is strongly reduced in FeCr nanowires due to pronounced changes in the density of states of the majority spin electrons. Measurements performed on Fe(7 nm)/Cu(10 nm) multilayer nanowires indicate a dominant contribution of charge carrier diffusion to the thermopower, as previously found in other magnetic multilayers, and a cancellation of the magnon-drag effect. The magneto-resistance and magneto-Seebeck effects measured on Fe/Cu multilayer nanowires allow the estimation of the spin-dependent Seebeck coefficient in Fe, which is about - 7.6 [Formula: see text]V/K at ambient temperature.

5.
Nanomaterials (Basel) ; 13(11)2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37299636

RESUMEN

Thermoelectric energy conversion based on flexible materials has great potential for applications in the fields of low-power heat harvesting and solid-state cooling. Here, we show that three-dimensional networks of interconnected ferromagnetic metal nanowires embedded in a polymer film are effective flexible materials as active Peltier coolers. Thermocouples based on Co-Fe nanowires exhibit much higher power factors and thermal conductivities near room temperature than other existing flexible thermoelectric systems, with a power factor for Co-Fe nanowire-based thermocouples of about 4.7 mW/K2m at room temperature. The effective thermal conductance of our device can be strongly and rapidly increased by active Peltier-induced heat flow, especially for small temperature differences. Our investigation represents a significant advance in the fabrication of lightweight flexible thermoelectric devices, and it offers great potential for the dynamic thermal management of hot spots on complex surfaces.

6.
Multimed Tools Appl ; : 1-17, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37362706

RESUMEN

Lung cancer has the highest incidence in the world. The standard tests for its diagnostics are medical imaging exams, sputum cytology, and lung biopsy. Computed Tomography (CT) of the chest plays an essential role in the early detection of nodules since it can allow for more treatment options and increases patient survival. However, the analysis of these exams is a tiring and error-prone process. Thus, computational methods can help the specialist in this analysis. This work addresses the classification of pulmonary nodules as benign or malignant on CT images. Our approach uses the pre-trained VGG16, VGG19, Inception, Resnet50, and Xception, to extract features from each 2D slice of the 3D nodules. Then, we use Principal Component Analysis to reduce the dimensionality of the feature vectors and make them all the same length. Then, we use Bag of Features (BoF) to combine the feature vectors of the different 2D slices and generate only one signature representing the 3D nodule. The classification step uses Random Forest. We evaluated the proposed method with 1,405 segmented nodules from the LIDC-IDRI database and obtained an accuracy of 95.34%, F1-Score of 91.73, kappa of 0.88, sensitivity of 90.53%, specificity of 97.26% and AUC of 0.99. The main conclusion was that the combination by BoF of features extracted from 2D slices using pre-trained architectures produced better results than training 2D and 3D CNNs in the nodules. In addition, the use of BoF also makes the creation of the nodule signature independent of the number of slices.

7.
ACS Omega ; 8(7): 6663-6668, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36844586

RESUMEN

A network of silver nanowires (Ag-NWs) is grown by electrodeposition in a nanoporous membrane with interconnected nanopores. This bottom-up approach fabrication method gives a conducting network with a 3D architecture and a high density of Ag-NWs. The network is then functionalized during the etching process, which leads to a high initial resistance as well as memristive behavior. The latter is expected to arise from the creation and the destruction of conducting silver filaments in the functionalized Ag-NW network. Moreover, after several cycles of measurement, the resistance of the network switches from a high-resistance regime in the GΩ range with tunnel conduction to a low-resistance regime presenting negative differential resistance in the kΩ range.

8.
Molecules ; 28(3)2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36770711

RESUMEN

3-heptylidene-4,6-dimethoxy-3H-isobenzofuran-1-one (Phthalide 1) is the precursor of three resorcinol lipids that have been described as potential chemotherapeutic agents and capable of potentiating the effects of cyclophosphamide. In this study, we evaluated the genotoxic potential, cell-killing potential, and interactions with cyclophosphamide and cisplatin of phthalide 1. Twelve groups were created from 120 mice: Negative Control, cyclophosphamide (100 mg/kg), cisplatin (6 mg/kg), Phthalide 1 (5, 10 and 20 mg/kg), and associations of 1 with cyclophosphamide and 1 with cisplatin. The results demonstrate that 1 increases (p < 0.05) the frequency of chromosomal damage, liver and kidney cell death, and splenic phagocytosis. The association of 1 with cyclophosphamide and cisplatin demonstrated a chemopreventive effect and, therefore, a reduction (p < 0.05) in the frequency of chromosomal damage. However, cell death and splenic phagocytosis did not suffer significant variations. As a result of the above, 1 has potential chemotherapeutic application and may be a candidate for developing a new generation of chemotherapeutics. In addition, it has characteristics to be used as a chemotherapy adjuvant in association with cyclophosphamide and cisplatin since it increases the frequency of cell death induced by chemotherapy. We also reported that the chemopreventive effect of 1, in association with cyclophosphamide and cisplatin, can prevent adverse effects (induction of DNA damage in non-tumor cells) without interfering with the mode of action of chemotherapy drugs and, therefore, without reducing the induction of cell death.


Asunto(s)
Anticarcinógenos , Antineoplásicos , Ratones , Animales , Cisplatino/efectos adversos , Antineoplásicos/toxicidad , Ciclofosfamida/toxicidad , Apoptosis , Daño del ADN , Anticarcinógenos/farmacología
9.
J Ethnopharmacol ; 303: 115991, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36470307

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Aristolochia triangularis Cham. has been used in Brazilian traditional medicine for various therapeutic purposes, including as a leaf-based infusion for diabetes management. AIM OF THE STUDY: This study was designed to chemically characterize an infusion of in natura A. triangularis leaves and evaluate the in vivo anti-hyperglycemic properties of this infusion. MATERIALS AND METHODS: Chemical composition was examined using liquid-liquid extraction procedure, chromatographic methods, NMR, and LC-MS/MS. The in vivo anti-hyperglycemic activity of the freeze-dried infusion of A. triangularis leaves (Inf-L-At) was assessed using oral glucose tolerance test (OGTT). Initially, normoglycemic male rats were pre-treated with orally administered Inf-L-At at doses of 62.5, 125, and 250 mg/kg for two consecutive days. On the day of the OGTT, fasting animals received a glucose load (4 g/kg) 30 min after treatment with Inf-L-At, and the blood glucose levels were verified at 15, 30, 60, and 180 min. Intestinal maltase, lactase, and sucrase activities and muscle and liver glycogen contents were also assessed after the OGTT. RESULTS: Inf-L-At extract led to glycemic reduction with no dose-response at 15, 30, and 60 min comparable to that of the antidiabetic drug glibenclamide and was accompanied by an increase in hepatic and muscle glycogen contents. Additionally, there was a significant statistically decrease in the in vitro activity of disaccharidases. Maltase and sucrase activities were inhibited at all doses, whereas lactase activity was inhibited only at 62.5 and 250 mg/kg. In total, 75 compounds were found in the infusion, including seven new ones, (7S*,8S*,7ꞌS*,8ꞌR*)-4,4ꞌ-dihydroxy-3,3ꞌ-dimethoxy-7,9ꞌ-epoxylignan-7ꞌ-ol; 4ꞌ-hydroxy-3ꞌ-methoxy-3,4-methylenedioxy-7,9ꞌ-epoxylignan-9,7ꞌ-diol; triangularisines A, B, and C; N-ethyl-N-methyl-affineine; and N-methyl pachyconfine, and one previously not described as a natural product, epi-secoisolariciresinol monomethyl ether. CONCLUSION: The results demonstrated the anti-hyperglycemic activity of the infusion from A. triangularis leaves and showed that it is a rich source of lignoids, alkaloids, and glycosylated flavonoids, which are known to exhibit antidiabetic effects and other biological properties that can be beneficial for patients with chronic hyperglycemia, thus certifying the popular use of this herbal drink.


Asunto(s)
Aristolochia , Ratas , Masculino , Animales , alfa-Glucosidasas , Extractos Vegetales/uso terapéutico , Cromatografía Liquida , Brasil , Espectrometría de Masas en Tándem , Hipoglucemiantes/uso terapéutico , Hojas de la Planta/química , Lactasa , Sacarasa , Glucemia
10.
Chem Res Toxicol ; 36(1): 66-82, 2023 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-36548215

RESUMEN

Cancer incidence is increasing, and the drugs are not very selective. These drugs cause adverse effects, and the cells become resistant. Therefore, new drugs are needed. Here, we evaluated the effects of ZIM, a candidate for chemotherapy, and 4-AA alone and in association with commercial chemotherapeutic agents. Subsequently, the results of ZIM and 4-AA were compared. Male Swiss mice were treated with doses of 12, 24, or 48 mg/kg ZIM or 4-AA alone or in association with cisplatin (6 mg/kg), doxorubicin (16 mg/kg), and cyclophosphamide (100 mg/kg). Biometric parameters, DNA damage (comet and micronuclei), cell death, and splenic phagocytosis were evaluated. DNA docking was also performed to confirm the possible interactions of ZIM and 4-AA with DNA. 4-AA has been shown to have low genotoxic potential, increase the frequency of cell death, and activate phagocytosis. ZIM causes genomic and chromosomal damage in addition to causing cell death and activating phagocytosis. In association with chemotherapeutical agents, both 4-AA and ZIM have a chemopreventive effect and, therefore, reduce the frequency of DNA damage, cell death, and splenic phagocytosis. The association of 4-AA and ZIM with commercial chemotherapeutic agents increased the frequency of lymphocytes compared to chemotherapeutic agents alone. Molecular docking demonstrated that ZIM has more affinity for DNA than 4-AA and its precursors (1 and 2). This was confirmed by the lower interaction energy of the complex (-119.83 kcal/mol). ZIM can break the DNA molecule and, therefore, its chemotherapeutic effect can be related to DNA damage. It is considered that ZIM has chemotherapeutic potential. However, it should not be used in combination with cisplatin, doxorubicin, and cyclophosphamide as it reduces the effects of these drugs.


Asunto(s)
Antineoplásicos , Cisplatino , Ratones , Animales , Masculino , Cisplatino/toxicidad , Ampirona/farmacología , Simulación del Acoplamiento Molecular , Muerte Celular , Ciclofosfamida/farmacología , Doxorrubicina/farmacología , Daño del ADN , ADN , Norbornanos/farmacología , Antineoplásicos/toxicidad
11.
Rev. bras. oftalmol ; 82: e0015, 2023. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1431667

RESUMEN

ABSTRACT Objective: To evaluate if participants, subjected to whole-body vibration, two different types of media (paper versus tablet) and two lighting environments (fluorescent versus LED), present a difference in eye-movement parameters during reading tasks. Methods: Fourteen adults silently read two different texts in each one of the eight randomized testing conditions (whole-body vibration versus media versus lighting), resulting in 16 different texts read per individual. Whole-body vibration was applied in the vertical direction, 5Hz and 0.8 m/s2 root-mean-square amplitude, a condition similar to those experienced by forklift truck drivers. Participants were in a sitting position with a backrest. An eye-tracker evaluated the eye-movements during the reading task. Results: Whole-body vibration significantly reduced the number of ocular fixations, and cross-correlation; and increased the reading efficiency, fixation duration, directional attack, and binocular anomalies. Neither the type of media nor the lighting environment interfered significantly with the eye-movements, both in situations with and without vibration. Conclusion: The results indicate that whole-body vibration interfered in the eye-movements during the reading task. This may impose a difficulty to process the visual information and to synchronously coordinate the binocular movements under vibration environments.


RESUMO Objetivo: Avaliar se participantes submetidos à vibração de corpo inteiro, a dois tipos diferentes de mídia (papel versus tablet) e a dois ambientes de iluminação (fluorescente versus LED) apresentam diferença nos parâmetros de movimento dos olhos durante tarefas de leitura. Métodos: Quatorze adultos leram silenciosamente dois textos diferentes em cada uma das oito condições de teste (vibração de corpo inteiro versus mídia versus iluminação), de forma aleatória, resultando em 16 textos diferentes lidos por indivíduo. A vibração de corpo inteiro foi aplicada no sentido vertical, com amplitude de 5Hz e 0,8m/s² da raiz do valor quadrático médio, em condição semelhante às vivenciadas pelos motoristas de empilhadeiras. Os participantes permaneceram em postura sentada com encosto. Um rastreador ocular avaliou os movimentos oculares durante a leitura. Resultados: A vibração de corpo inteiro reduziu significativamente o número de fixações oculares e a correlação cruzada entre os olhos e aumentou a eficiência de leitura, duração da fixação, ataque direcional e anomalias binoculares. Nem o tipo de mídia nem as condições de ambientes de iluminação interferiram significativamente nos movimentos oculares, tanto em situações com ou sem vibração. Conclusão: Os resultados indicam que a Vibração de Corpo Inteiro pode interferir nos movimentos oculares durante a leitura. Isso pode impor uma dificuldade no processamento da informação visual e na coordenação síncrona dos movimentos binoculares em ambientes de vibração.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Lectura , Vibración , Iluminación , Computadoras de Mano , Movimientos Oculares/fisiología , Estudios Prospectivos , Fijación Ocular/fisiología , Luz
12.
Sci Rep ; 12(1): 10605, 2022 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-35739153

RESUMEN

We investigate the impact of the DC current-induced Ampère-Oersted field on the dynamics of a vortex based spin-torque nano-oscillator. In this study we compare micromagnetic simulations performed using mumax[Formula: see text] and our analytical model based on the Thiele equation approach. The latter is improved by adding two important corrections to the Thiele equation approach. The first is related to the magneto-static contribution and depends on the aspect ratio of the magnetic dot. The second is a full analytical description of the Ampère-Oersted field contribution. The model describes quantitatively the simulation results in the resonant regime as well as the impact of the Ampère-Oersted field. Depending on the relative orientation between the vortex in-plane curling magnetisation (chirality) and the Ampère-Oersted field a strong splitting phenomenon appears in the fundamental properties (frequency and vortex core position) of the nano-oscillator. Thus, we show that the Ampère-Oersted field should not be neglected as it has a high impact on the spin-torque vortex oscillator dynamics.

13.
J Bodyw Mov Ther ; 31: 77-83, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35710226

RESUMEN

INTRODUCTION: The aim of this study was to verify the effects of a 4-week detraining period on the functional capacity of elderly women with type-2 diabetes (T2D) after 12 weeks of a PILATES training program. METHODS: Twenty-two individuals with T2D were randomly allocated into two groups: CONTROL (n = 11; 67.5 ± 6.3 years; 154.7 ± 6.1 cm; 73.5 ± 6.1 kg; calorie intake: 1487.5 ± 360.6 kcal/day) and PILATES (n = 11; 65.5 ± 5.5 years; 155.0 ± 4.5 cm; 66.2 ± 5.4 kg; calorie intake: 1289.3 ± 385.0 kcal/day). The PILATES group participated at a 12-week PILATES program at moderate intensity, 3x/week with each session lasting 60-min. The functional capacity was evaluated in the baseline (PRE), after 12-weeks (POST) and 4-week detraining period (4W_DT). The general index of functional capacity (GIFC) was calculated for all participants. RESULTS: In the PILATES group there was a reduction in performance (increased test time) for the GIFC after 4W_DT in relation to POST (p < 0.05), however, GIFC showing maintenance of performance gain in relation to the PRE (p > 0.05) (PRE: 36.0 ± 5.5 s vs. POST: 27.2 ± 4.0 s vs. 4W_DT: 29.0 ± 4.2 s). The CONTROL group had worse performance than the GIFC POST (35.3 ± 4.6 s) and 4W_DT (35.4 ± 4.6 s) when compared to the PILATES group (F = 106.967; np2 = 0.842; p < 0.001). CONCLUSION: A period of 4W_DT was not able to reduce the functional gains of elderly women with T2D after 12 weeks of PILATES training. These results have a practical application for training professionals, enabling better control and planning of training interruptions on the PILATES method for elderly women with T2D.


Asunto(s)
Diabetes Mellitus Tipo 2 , Técnicas de Ejercicio con Movimientos , Anciano , Diabetes Mellitus Tipo 2/terapia , Técnicas de Ejercicio con Movimientos/métodos , Femenino , Humanos
14.
Comput Biol Med ; 145: 105442, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35344867

RESUMEN

Chest radiographies, or chest X-rays, are the most standard imaging exams used in daily hospitals. Responsible for assisting in detecting numerous pathologies and findings that directly interfere in the patient's life, this exam is therefore crucial in screening patients. This work proposes a methodology based on a Convolutional Neural Networks (CNNs) ensemble to aid the diagnosis of chest X-ray exams by screening them with a high probability of being normal or abnormal. In the development of this study, a private dataset with frontal and lateral projections X-ray images was used. To build the ensemble model, VGG-16, ResNet50 and DenseNet121 architectures, which are commonly used in the classification of Chest X-rays, were evaluated. A Confidence Threshold (CTR) was used to define the predictions into High Confidence Normal (HCn), Borderline classification (BC), or High Confidence Abnormal (HCa). In the tests performed, very promising results were achieved: 54.63% of the exams were classified with high confidence; of the normal exams, 32% were classified as HCn with an false discovery rate (FDR) of 1.68%; and as to the abnormal exams, 23% were classified as HCa with 4.91% false omission rate (FOR).


Asunto(s)
Aprendizaje Profundo , Humanos , Redes Neurales de la Computación , Radiografía , Rayos X
15.
Nat Commun ; 13(1): 1016, 2022 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-35197449

RESUMEN

Deep learning has an increasing impact to assist research, allowing, for example, the discovery of novel materials. Until now, however, these artificial intelligence techniques have fallen short of discovering the full differential equation of an experimental physical system. Here we show that a dynamical neural network, trained on a minimal amount of data, can predict the behavior of spintronic devices with high accuracy and an extremely efficient simulation time, compared to the micromagnetic simulations that are usually employed to model them. For this purpose, we re-frame the formalism of Neural Ordinary Differential Equations to the constraints of spintronics: few measured outputs, multiple inputs and internal parameters. We demonstrate with Neural Ordinary Differential Equations an acceleration factor over 200 compared to micromagnetic simulations for a complex problem - the simulation of a reservoir computer made of magnetic skyrmions (20 minutes compared to three days). In a second realization, we show that we can predict the noisy response of experimental spintronic nano-oscillators to varying inputs after training Neural Ordinary Differential Equations on five milliseconds of their measured response to a different set of inputs. Neural Ordinary Differential Equations can therefore constitute a disruptive tool for developing spintronic applications in complement to micromagnetic simulations, which are time-consuming and cannot fit experiments when noise or imperfections are present. Our approach can also be generalized to other electronic devices involving dynamics.

16.
Saude e pesqui. (Impr.) ; 15(1): e9938, abr./jun. 2022.
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1368094

RESUMEN

O objetivo do presente estudo foi analisar o efeito da facilitação neuromuscular proprioceptiva (FNP), realizada em meio terrestre e aquático, na flexibilidade de posteriores da coxa e extensores do quadril em adultos saudáveis. Trata-se de um ensaio clínico aleatorizado. A amostra foi composta por 16 adultos (18 a 35 anos) de ambos os sexos, randomizados em dois grupos: experimental (GE, n=08), submetido ao alongamento por FNP no meio aquático; e controle (GC, n=08), que recebeu a FNP no meio terrestre. A intervenção foi realizada durante seis semanas, com duas sessões semanais. Pré e pós-intervenção a flexibilidade do quadril foi avaliada pela amplitude de movimento (ADM) utilizando um goniômetro posicionado sobre essa articulação. E para determinar a flexibilidade dos músculos posteriores da coxa foi utilizado o teste sentar e alcançar. Ambas as intervenções, propiciaram um aumento significativo na flexibilidade do GE e GC (p<0,05), entretanto não houve efeito significativo de ambiente (p>0,05).


The aim of the present study was to analyze the effect of proprioceptive neuromuscular facilitation (PNF), performed in land and aquatic environments, on the flexibility of the posterior thigh and hip extensors in healthy adults. This is a randomized clinical trial. The sample was composed of 16 adults (18 to 35 years old) of both sexes, randomized into two groups: experimental (EG, n=08), submitted to PNF stretching in the aquatic environment; and control (CG, n=08), which received PNF on land. The intervention was performed during six weeks, with two weekly sessions. Before and after the intervention, hip flexibility was assessed by range of motion (ROM) using a goniometer positioned over this joint. And to determine the flexibility of the posterior thigh muscles, the sit and reach test was used. Both interventions provided a significant increase in flexibility in the EG and CG (p<0.05), however there was no significant effect on the environment (p>0.05).

17.
Drug Chem Toxicol ; 45(4): 1504-1521, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33252270

RESUMEN

Pachira aquatica is a species used for medicinal and food purposes and has numerous phytochemicals that may have systemic toxic effects and damage to genetic material. This study aimed to evaluate acute and short-term oral toxicity, as well as genotoxic and clastogenic effects of oil extracted from P. aquatica (PASO) seeds in rats and Drosophila melanogaster. The results obtained with biochemical and hematological analyses did not show significant changes in any evaluated parameters when compared with reference values for the species used in the study. Data from the histopathological analysis corroborated results found in this study. These findings indicate low acute and short-term toxicity following oral PASO exposure in rats under the experimental conditions tested. Tests performed in rats showed that PASO did not present significant genotoxic or clastogenic effects on the cells analyzed with the three doses tested. Treatment with PASO in the offspring of HB crossing, which showed high cytochrome P450 levels, did not exhibit genotoxic activity, as demonstrated by the SMART test. These results suggest that products from the hepatic oil metabolism did not show genotoxicity under the conditions tested. Together, the results indicate that, under the experimental conditions tested, PASO is safe for repeated intake. As PASO exhibited low potential to cause harmful effects on living organisms, our study encourages further research aimed at assessing its pharmacological activity, since it is a widely consumed plant.


Asunto(s)
Bombacaceae , Malvaceae , Animales , Drosophila melanogaster , Mutágenos/química , Extractos Vegetales/farmacología , Ratas , Semillas , Pruebas de Toxicidad Aguda
18.
Trop Anim Health Prod ; 53(6): 524, 2021 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-34705124

RESUMEN

Whole genome sequencing of bovine breeds has allowed identification of genetic variants in milk protein genes. However, functional repercussion of such variants at a molecular level has seldom been investigated. Here, the results of a multistep Bioinformatic analysis for functional characterization of recently identified genetic variants in Brazilian Gyr and Guzerat breeds is described, including predicted effects on the following: (i) evolutionary conserved nucleotide positions/regions; (ii) protein function, stability, and interactions; (iii) splicing, branching, and miRNA binding sites; (iv) promoters and transcription factor binding sites; and (v) collocation with QTL. Seventy-one genetic variants were identified in the caseins (CSN1S1, CSN2, CSN1S2, and CSN3), LALBA, LGB, and LTF genes. Eleven potentially regulatory variants and two missense mutations were identified. LALBA Ile60Val was predicted to affect protein stability and flexibility, by reducing the number the disulfide bonds established. LTF Thr546Asn is predicted to generate steric clashes, which could mildly affect iron coordination. In addition, LALBA Ile60Val and LTF Thr546Asn affect exonic splicing enhancers and silencers. Consequently, both mutations have the potential of affecting immune response at individual level, not only in the mammary gland. Although laborious, this multistep procedure for classifying variants allowed the identification of potentially functional variants for milk protein genes.


Asunto(s)
Caseínas , Proteínas de la Leche , Animales , Bovinos/genética , Simulación por Computador , Mutación , Regiones Promotoras Genéticas
19.
Comput Biol Med ; 136: 104744, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34388465

RESUMEN

COVID-19 is a respiratory disease that, as of July 15th, 2021, has infected more than 187 million people worldwide and is responsible for more than 4 million deaths. An accurate diagnosis of COVID-19 is essential for the treatment and control of the disease. The use of computed tomography (CT) has shown to be promising for evaluating patients suspected of COVID-19 infection. The analysis of a CT examination is complex, and requires attention from a specialist. This paper presents a methodology for detecting COVID-19 from CT images. We first propose a convolutional neural network architecture to extract features from CT images, and then optimize the hyperparameters of the network using a tree Parzen estimator to choose the best parameters. Following this, we apply a selection of features using a genetic algorithm. Finally, classification is performed using four classifiers with different approaches. The proposed methodology achieved an accuracy of 0.997, a kappa index of 0.995, an AUROC of 0.997, and an AUPRC of 0.997 on the SARS-CoV-2 CT-Scan dataset, and an accuracy of 0.987, a kappa index of 0.975, an AUROC of 0.989, and an AUPRC of 0.987 on the COVID-CT dataset, using our CNN after optimization of the hyperparameters, the selection of features and the multi-layer perceptron classifier. Compared with pretrained CNNs and related state-of-the-art works, the results achieved by the proposed methodology were superior. Our results show that the proposed method can assist specialists in screening and can aid in diagnosing patients with suspected COVID-19.


Asunto(s)
COVID-19 , Aprendizaje Profundo , Algoritmos , Humanos , Redes Neurales de la Computación , SARS-CoV-2 , Tomografía Computarizada por Rayos X
20.
J Ethnopharmacol ; 280: 114478, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34343649

RESUMEN

ETHNOPHARMACOLOGY RELEVANCE: Aleurites moluccana is popularly used for the diseases like ulcers, fever, headache, asthma, conjunctivitis, gonorrhea, inflammation, hepatitis, and rheumatism. The seed, also known as "noz da Índia", has been popularly consumed for weight loss purposes but reports of toxicity have been associated with its ingestion. In the literature, there are not enough studies to elucidate its toxicology, so evaluating the general and genetic toxicological of A. moluccana seeds can provide data to ensure their intake. AIM OF THE STUDY: The objective of the present study was to elucidate the oral toxicity, mutagenicity, genotoxicity and cytotoxicity of A. moluccana seeds in vitro and in vivo assays. MATERIALS AND METHODS: The chemical composition of the aqueous extract of A. moluccana seeds (AEAMS) was analyzed in relation to phenolic compounds, tannins, flavonoids and fatty acid. For the in vitro assays, the cytotoxic potential was assessed by the MTS assay whereas the mutagenic potential was assessed by the Ames test. For in vivo assays, was conducted an acute oral toxicity study, with "Up-and-Down Procedure" and repeated dose toxicity with "Repeated Dose 28-Day Oral Toxicity". To assess genetic damage, mutagenic potential was assessed by the micronucleus test whereas the polychromatic erythrocyte/normochromatic erythrocyte ratio was obtained with bone marrow cells to determine the cytotoxic potential and genotoxic potential was assessed by the comet assay using peripheral blood cells. RESULTS: AEAMS did not show cytotoxic and mutagenic potential in vitro. No clinical signs of toxicity were observed in animals after the acute oral toxicity test, suggesting that the LD50 of aqueous extract of A. moluccana seeds > 2000 mg/kg in a single dose by intragastric route. However, in toxicity at repeated doses for 28 days, the doses initially established (250; 500 and 750 mg/kg/day by intragastric route) caused mortality in the animals and the reestablished doses (25, 50 and 100 mg/kg/day by intragastric route) showed no changes in parameters or clinical signs attributed to toxicity. Furthermore, AEAMS also did not show mutagenic, genotoxic and cytotoxic potential in vivo. CONCLUSIONS: AEAMS did not show cytotoxic, genotoxic and mutagenic potential in vitro and in vivo. And although the AEAMS has an LD50 > 2000 mg/kg, and does not have physiological, biochemical, hematological, histopathological changes or clinical signs related to toxicity when administered in low concentrations and for a short period, in high concentrations and continued use caused toxicity and mortality in Wistar rats. In order to obtain complementary results, is recommended highly that further mid and long-term toxicological studies are investigated, and in no-rodent specie.


Asunto(s)
Aleurites/química , Daño del ADN/efectos de los fármacos , Extractos Vegetales/toxicidad , Animales , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Femenino , Dosificación Letal Mediana , Masculino , Pruebas de Micronúcleos , Extractos Vegetales/administración & dosificación , Ratas , Ratas Wistar , Semillas , Pruebas de Toxicidad Aguda
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