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1.
Biotech Histochem ; : 1-7, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38726944

RESUMO

Anterior cruciate ligament injuries are frequent afflictions related to sports or physical trauma. Autograft reconstruction strategies cause secondary injury to the patient. One alternative, supported by clinical evidence, is porcine xenografts. For clinical use, xenografts must be conditioned to avoid immune rejection. The most widely accepted procedure is tissue decellularization. We analyzed three decellularization strategies: the application of the anionic detergent sodium dodecyl sulfate (SDS), sonication, and freezing and thawing cycles. The treated tissues were evaluated histologically using H&E, Masson's trichrome, Verhoeff-van Gieson staining, and DAPI for fluorescent staining of nuclei. Finally, collagen fiber preservation was evaluated by quantifying this protein by colorimetry. The most efficient decellularization techniques were sonication and SDS. Collagen fibers were preserved in all experimental conditions.

2.
Arch Pathol Lab Med ; 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38797525

RESUMO

CONTEXT.­: Interpretation of alkaline phosphatase (ALP) activity is essential for the diagnosis of certain diseases. ALP changes during life and may vary between different populations. OBJECTIVE.­: To establish reference intervals (RIs) and percentile charts for ALP activity in the Spanish population through a multicentric observational study and to compare the RIs to those defined in other countries. DESIGN.­: A total of 662 350 ALP measurements from individuals ages 0 to 99 years from 9 Spanish tertiary care centers collected between 2020 and 2022 were analyzed. This study is the largest published in the literature to date. RESULTS.­: Continuous percentile charts for ALP according to sex and age were established which can be used as RIs. Higher levels are reached during the first weeks of life. In puberty, a differential evolution is observed in both sexes, reaching a peak at 10 to 13 years of age in boys and remaining stable in girls at this age. Significant differences were also observed in adults, higher in men between ages 20 and 49 years and between ages 50 and 79 years in women, as reported in some countries. CONCLUSIONS.­: ALP activity follows an age- and sex-dependent fluctuation with geographic differences. It is important to have appropriate reference values for each population in order to allow for a correct diagnostic interpretation and early diagnosis of diseases related to ALP abnormalities.

3.
Int Orthop ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589709

RESUMO

PURPOSE: Third and fourth-generation minimal invasive osteotomies (MIO) for the treatment of hallux valgus (HV) have become popular procedures worldwide with promising results due to the improvement in the fixation method. The tricortical cannulated screw placement remains a complex procedure that is technically challenging and requires a long skill learning curve with high radiation exposure mainly in the form of intensifier shots (IS) required for the MIO fixation. This study aims to compare the number of X-ray IS required using three different techniques for the cannulated guide placement. METHODS: A retrospective cross-sectional observational and comparative study was conducted to assess the number of X-rays IS required for correct cannulated screw guide placement using three different techniques: traditional perforator, the drill and joystick, and K-wire first techniques. RESULTS: A total of 53 MIS procedures from thirty-one patients in two different hospitals were included. IS X-rays were 155.1 ± 29.7 in the traditional technique (n = 14), 143.0 ± 43.2 in the drill and joystick technique (n = 22), and 85 ± 18.7 in the K-wires first technique (n = 17), p = < 0.001 using one-way ANOVA. CONCLUSIONS: The K-wire first technique statistically significantly decreases X-ray IS numbers p ≤ 0.001. There were no statistically significant differences between the traditional (after osteotomy K-wire placement) and the drill and joystick techniques (p = 0.36).

4.
J Mech Behav Biomed Mater ; 152: 106413, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38281439

RESUMO

Keratoconus is a progressive ocular disorder affecting the corneal tissue, leading to irregular astigmatism and decreased visual acuity. The architectural organization of corneal tissue is altered in keratoconus, however, data from ex vivo testing of biomechanical properties of keratoconic corneas are limited and it is unclear how their results relate to true mechanical properties in vivo. This study explores the mechanical properties of keratoconic corneas through numerical simulations of non-contact tonometry (NCT) reproducing the clinical test of the Corvis ST device. Three sensitivity analyses were conducted to assess the impact of corneal material properties, size, and location of the pathological area on NCT results. Additionally, novel asymmetry-based indices were proposed to better characterize corneal deformations and improve the diagnosis of keratoconus. Our results show that the weakening of corneal material properties leads to increased deformation amplitude and altered biomechanical response. Furthermore, asymmetry indices offer valuable information for locating the pathological tissue. These findings suggest that adjusting the Corvis ST operation, such as a camera rotation, could enhance keratoconus detection and provide insights into the relative position of the affected area. Future research could explore the application of these indices in detecting early-stage keratoconus and assessing the fellow eye's risk for developing the pathology.


Assuntos
Ceratocone , Humanos , Ceratocone/diagnóstico , Córnea , Tonometria Ocular , Biomarcadores , Manometria
5.
Biomech Model Mechanobiol ; 23(2): 525-537, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38063955

RESUMO

Transcatheter aortic valve implantation (TAVI) and thoracic endovascular aortic repair (TEVAR) are minimally invasive procedures for treating aortic valves and diseases. Finite element simulations have proven to be valuable tools in predicting device-related complications. In the literature, the inclusion of aortic pre-stress has not been widely investigated. It plays a crucial role in determining the biomechanical response of the vessel and the device-tissue interaction. This study aims at demonstrating how and when to include the aortic pre-stress in patient-specific TAVI and TEVAR simulations. A percutaneous aortic valve and a stent-graft were implanted in aortic models reconstructed from patient-specific CT scans. Two scenarios for each patient were compared, i.e., including and neglecting the wall pre-stress. The neglection of pre-stress underestimates the contact pressure of 48% and 55%, the aorta stresses of 162% and 157%, the aorta strains of 77% and 21% for TAVI and TEVAR models, respectively. The stent stresses are higher than 48% with the pre-stressed aorta in TAVI simulations; while, similar results are obtained in TEVAR cases. The distance between the device and the aorta is similar with and without pre-stress. The inclusion of the aortic wall pre-stress has the capability to give a better representation of the biomechanical behavior of the arterial tissues and the implanted device. It is suggested to include this effect in patient-specific simulations replicating the procedures.


Assuntos
Aneurisma da Aorta Torácica , Procedimentos Endovasculares , Substituição da Valva Aórtica Transcateter , Humanos , Procedimentos Endovasculares/métodos , Valva Aórtica/cirurgia , Stents , Aorta/cirurgia , Substituição da Valva Aórtica Transcateter/métodos , Resultado do Tratamento , Aorta Torácica/cirurgia , Prótese Vascular
6.
Artigo em Português | LILACS | ID: biblio-1551115

RESUMO

Este estudo objetivou estimar a prevalência do uso do cigarro eletrônico e a associação com fatores preditores. Trata-se de um estudo transversal, analítico, com amostra probabilística de universitários matriculados em um Centro Universitário de Montes Claros, Minas Gerais, Brasil no segundo semestre de 2022. A variável dependente referiu-se ao uso do cigarro eletrônico. As variáveis independentes referiram a fatores sociodemográficas, laborais e comportamentais. A associação entre as variáveis investigadas e a prevalência do uso do CE foi verificada pela análise bivariada e a regressão de Poisson. Foram entrevistados 730 universitários, com a média de idade de anos 22,56 (±6,25). Destes, 21,8 % faziam o uso cigarro eletrônico e após a análise multivariada manteve-se associado ao desfecho não ter companheiro (RP= 3,31; IC95% 1,04-10,48), morar com amigos/sozinho (RP=1,53; IC95% 1,07-2,18), ter histórico de usuários de cigarro eletrônico na residência (RP= 1,76; IC95%: 1,17- 1,89), consumir bebida alcoólica (RP= 3,07; IC95%: 1,72-5,49) e não praticar atividade física (RP= 3,37; IC95% 2,35-4,83). Conhecer sobre o cigarro eletrônico foi fator protetor (RP= 0,31 IC95% 0,20-0,46). Registrou-se elevada prevalência do uso do cigarro eletrônico, e manteve associados a fatores sociodemográficos e comportamentais. Esses achados chamam a atenção para a necessidade de novas medidas regulatórias, a fim de reduzir o uso desse dispositivo.


This study aimed to estimate the prevalence of e-cigarette use and the association with predictors. This is a cross-sectional, analytical study with a probabilistic sample of university students enrolled in a University Center of Montes Claros, Minas Gerais, Brazil in the second half of 2022. The dependent variable referred to the use of electronic cigarettes. The independent variables referred to sociodemographic, labor and behavioral factors. The association between the variables investigated and the prevalence of EC use was verified by bivariate analysis and Poisson regression. A total of 730 university students were interviewed, with a mean age of 22.56 (±6.25). Of these, 21.8% used electronic cigarettes and after multivariate analysis, it remained associated with the outcome of not having a partner (PR= 3.31; CI95% 1.04-10.48), living with friends/alone (PR=1.53; CI95% 1.07-2.18), having a history of e-cigarette users in the residence (PR= 1.76; CI95%: 1.17- 1.89), alcohol consumption (PR= 3.07; CI95%: 1.72-5.49) and not practicing physical activity (PR= 3.37; IC95% 2.35-4.83). Knowing about electronic cigarettes was a protective factor (PR= 0.31 CI95% 0.20-0.46). There was a high prevalence of e-cigarette use, and it was associated with sociodemographic and behavioral factors. These findings draw attention to the need for new regulatory measures in order to reduce the use of this device.


Este estudio tuvo como objetivo estimar la prevalencia del uso de cigarrillos electrónicos y la asociación con predictores. Se trata de un estudio analítico transversal con una muestra probabilística de estudiantes universitarios matriculados en un Centro Universitario de Montes Claros, Minas Gerais, Brasil, en el segundo semestre de 2022. La variable dependiente se refería al uso de cigarrillos electrónicos. Las variables independientes se refirieron a factores sociodemográficos, laborales y conductuales. La asociación entre las variables investigadas y la prevalencia de uso de CE fue verificada por análisis bivariado y regresión de Poisson. Fueron entrevistados 730 estudiantes universitarios, con una edad promedio de 22,56 (±6,25). De estos, 21,8% utilizaron cigarrillos electrónicos y después del análisis multivariado, se mantuvo asociado con el resultado de no tener pareja (RP= 3,31; IC95% 1,04-10,48), vivir con amigos/solo (RP=1,53; IC95% 1,07-2,18), con antecedentes de usuarios de cigarrillos electrónicos en la residencia (RP= 1,76; IC95%: 1,17- 1,89), consumo de alcohol (RP= 3,07; IC95%: 1,72-5,49) y no practicar actividad física (RP= 3,37; IC95% 2,35-4,83). El conocimiento de los cigarrillos electrónicos fue un factor protector (RP= 0,31 IC95% 0,20-0,46). Hubo una alta prevalencia de uso de cigarrillos electrónicos, y se asoció con factores sociodemográficos y de comportamiento. Estos hallazgos llaman la atención sobre la necesidad de nuevas medidas regulatorias para reducir el uso de este dispositivo.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Universidades , Prevalência , Sistemas Eletrônicos de Liberação de Nicotina/instrumentação , Comportamento/fisiologia , Conhecimento
7.
BMC Genomics ; 24(1): 696, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37986038

RESUMO

BACKGROUND: Isabel Island is a Mexican volcanic island primarily composed of basaltic stones. It features a maar known as Laguna Fragatas, which is classified as a meromictic thalassohaline lake. The constant deposition of guano in this maar results in increased levels of phosphorus, nitrogen, and carbon. The aim of this study was to utilize high-quality genomes from the genus Halomonas found in specialized databases as a reference for genome mining of moderately halophilic bacteria isolated from Laguna Fragatas. This research involved genomic comparisons employing phylogenetic, pangenomic, and metabolic-inference approaches. RESULTS: The Halomonas genus exhibited a large open pangenome, but several genes associated with salt metabolism and homeostatic regulation (ectABC and betABC), nitrogen intake through nitrate and nitrite transporters (nasA, and narGI), and phosphorus uptake (pstABCS) were shared among the Halomonas isolates. CONCLUSIONS: The isolated bacteria demonstrate consistent adaptation to high salt concentrations, and their nitrogen and phosphorus uptake mechanisms are highly optimized. This optimization is expected in an extremophile environment characterized by minimal disturbances or abrupt seasonal variations. The primary significance of this study lies in the dearth of genomic information available for this saline and low-disturbance environment. This makes it important for ecosystem conservation and enabling an exploration of its biotechnological potential. Additionally, the study presents the first two draft genomes of H. janggokensis.


Assuntos
Halomonas , Halomonas/genética , Halomonas/metabolismo , Lagos/microbiologia , Filogenia , Ecossistema , Genômica , Nitrogênio/metabolismo , Fósforo/metabolismo , RNA Ribossômico 16S/genética , DNA Bacteriano/genética
8.
J Neuroinflammation ; 20(1): 230, 2023 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-37805585

RESUMO

Stroke is the most common cause of long-term disability and places a high economic burden on the global healthcare system. Functional outcomes from stroke are largely determined by the extent of ischemic injury, however, there is growing recognition that systemic inflammatory responses also contribute to outcomes. Mast cells (MCs) rapidly respond to injury and release histamine (HA), a pro-inflammatory neurotransmitter that enhances inflammation. The gut serves as a major reservoir of HA. We hypothesized that cromolyn, a mast cell stabilizer that prevents the release of inflammatory mediators, would decrease peripheral and central inflammation, reduce MC trafficking to the brain, and improve stroke outcomes. We used the transient middle cerebral artery occlusion (MCAO) model of ischemic stroke in aged (18 mo) male mice to investigate the role of MC in neuroinflammation post-stroke. After MCAO we treated mice with 25 mg/kg body weight of cromolyn (MC stabilizer) by oral gavage. Cromolyn was administered at 3 h, 10 h, 24 h and every 24 h for 3 days post-stroke. Three control groups were used. One group underwent a sham surgery and was treated with cromolyn, one received sham surgery with PBS vehicle and the third underwent MCAO with PBS vehicle. Mice were euthanized at 24 h and 3 days post-stroke. Cromolyn administration significantly reduced MC numbers in the brain at both 24 h and 3 days post-stroke. Infarct volume was not significantly different between groups, however improved functional outcomes were seen at 3 days post-stroke in mice that received cromolyn. Treatment with cromolyn reduced plasma histamine and IL-6 levels in both the 24-h and 3-day cohorts. Gut MCs numbers were significantly reduced after cromolyn treatment at 24 h and 3 days after stroke. To determine if MC trafficking from the gut to the brain occurred after injury, GFP+MCs were adoptively transferred to c-kit-/- MC knock-out animals prior to MCAO. 24 h after stroke, elevated MC recruitment was seen in the ischemic brain. Preventing MC histamine release by cromolyn improved gut barrier integrity and an improvement in stroke-induced dysbiosis was seen with treatment. Our results show that preventing MC histamine release possesses prevents post-stroke neuroinflammation and improves neurological and functional outcomes.


Assuntos
Liberação de Histamina , Acidente Vascular Cerebral , Humanos , Camundongos , Masculino , Animais , Mastócitos , Cromolina Sódica/farmacologia , Cromolina Sódica/uso terapêutico , Histamina , Doenças Neuroinflamatórias , Acidente Vascular Cerebral/complicações , Inflamação/tratamento farmacológico , Inflamação/etiologia , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Isquemia
10.
Aging Cell ; 22(11): e13977, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37675802

RESUMO

Iron imbalance in the brain negatively affects brain function. With aging, iron levels increase in the brain and contribute to brain damage and neurological disorders. Changes in the cerebral vasculature with aging may enhance iron entry into the brain parenchyma, leading to iron overload and its deleterious consequences. Endothelial senescence has emerged as an important contributor to age-related changes in the cerebral vasculature. Evidence indicates that iron overload may induce senescence in cultured cell lines. Importantly, cells derived from female human and mice generally show enhanced senescence-associated phenotype, compared with males. Thus, we hypothesize that cerebral endothelial cells (CEC) derived from aged female mice are more susceptible to iron-induced senescence, compared with CEC from aged males. We found that aged female mice, but not males, showed cognitive deficits when chronically treated with ferric citrate (FC), and their brains and the brain vasculature showed senescence-associated phenotype. We also found that primary culture of CEC derived from aged female mice, but not male-derived CEC, exhibited senescence-associated phenotype when treated with FC. We identified that the transmembrane receptor Robo4 was downregulated in the brain vasculature and in cultured primary CEC derived from aged female mice, compared with those from male mice. We discovered that Robo4 downregulation contributed to enhanced vulnerability to FC-induced senescence. Thus, our study identifies Robo4 downregulation as a driver of senescence induced by iron overload in primary culture of CEC and a potential risk factor of brain vasculature impairment and brain dysfunction.


Assuntos
Senescência Celular , Sobrecarga de Ferro , Camundongos , Humanos , Animais , Masculino , Feminino , Idoso , Senescência Celular/fisiologia , Células Endoteliais , Envelhecimento , Ferro , Receptores de Superfície Celular
11.
Sci Total Environ ; 903: 165984, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-37574072

RESUMO

Currently, discharge regulations for wastewater treatment plants (WWTPs) are based on conventional parameters, but more is needed to ensure safe water reuse. In particular, emerging pollutants, as antimicrobials and antibiotic resistance genes (ARGs), are not considered. This research focuses on the fate of emerging biological contaminants during wastewater treatment in Mexico City. intI1 and the ARGs cphA-02, OXA-10 and sul1 were analyzed by qPCR; pathogenic bacteria species were characterized by high throughput sequencing of complete 16S rRNA gene, and fragments of SARS-CoV-2 were quantified by RT-qPCR. Conventional parameters (chemical oxygen demand and coliform bacteria) were also determined. Two sampling campaigns (rainy and dry seasons) were carried out in four municipal WWTPs in Mexico City, representing five biological treatment processes: conventional activated sludge, extended aeration activated sludge, membrane bioreactor, direct anaerobic digestion, and constructed wetland, followed by ultraviolet light or chlorine disinfection. In most cases, gene fragments of SARS-CoV-2 were eliminated below the detection limit of RT-qPCR. The abundance of intI1 positively correlated with the sul1, OXA-10, and cphA-02 abundances; intI1 and the ARGs here studied were partially removed in the WWTPs, and in most cases, the number of copies per second discarded in the sludge were higher those in the effluent. The treatment processes decreased the abundance of dominant bacterial groups in the raw wastewater, while enriching bacterial groups in the effluent and the biological sludge, with possible pollutant removal capabilities. Bacterial communities in the raw wastewater showed the predominance of the genus Arcobacter (from 62.4 to 86.0 %) containing potentially pathogenic species. Additionally, DNA of some species persisted after the treatment processes: A. johnsonii, A. junii, A. caviae, A. hydrophila, A. veronii, A. butzleri, A. cryaerophilus, Chryseobacterium indologenes, Hafnia paralvei, M. osloensis, Pseudomonas putida and Vibrio cholerae, which deserves special attention in future regulation for safe water reuse.

12.
Behav Sci (Basel) ; 13(7)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37503995

RESUMO

Autism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder characterised by deficits in social interaction and communication, as well as restricted and stereotyped interests. Due of the high prevalence of gastrointestinal disorders in individuals with ASD, researchers have investigated the gut microbiota as a potential contributor to its aetiology. The relationship between the microbiome, gut, and brain (microbiome-gut-brain axis) has been acknowledged as a key factor in modulating brain function and social behaviour, but its connection to the aetiology of ASD is not well understood. Recently, there has been increasing attention on the relationship between the immune system, gastrointestinal disorders and neurological issues in ASD, particularly in relation to the loss of specific species or a decrease in microbial diversity. It focuses on how gut microbiota dysbiosis can affect gut permeability, immune function and microbiota metabolites in ASD. However, a very complete study suggests that dysbiosis is a consequence of the disease and that it has practically no effect on autistic manifestations. This is a review of the relationship between the immune system, microbial diversity and the microbiome-gut-brain axis in the development of autistic symptoms severity and a proposal of a novel role of gut microbiome in ASD, where dysbiosis is a consequence of ASD-related behaviour and where dysbiosis in turn accentuates the autistic manifestations of the patients via the microbiome-gut-brain axis in a feedback circuit.

13.
Environ Monit Assess ; 195(8): 975, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37474709

RESUMO

The study explores the spatio-temporal variation of water quality parameters in the Hooghly estuary, which is considered an ecologically-stressed shallow estuary and a major distributary for the Ganges River. The estimated parameters are chlorophyll-a, total suspended matter (TSM), and chromophoric dissolved organic matter (CDOM). The Sentinel-3 OLCI remote sensing imageries were analyzed for the duration of October 2018 to February 2019. We observed that the water quality of the Hooghly estuaries is comparatively low-oxygenated, mesotrophic, and phosphate-limited. Ongoing channel dredging for maintaining shipping channel depth keeps the TSM in the estuary at an elevated level, with the highest amount of TSM observed during March of 2019 (41.59g m-3) at station A, upstream point. Since the pre-monsoon season, TSM data shows a decreasing trend towards the mouth of the estuary. Chl-a concentration is higher during pre-monsoon than monsoon and post-monsoon periods, with the highest value observed in April at 1.09 mg m-3 in station D during the pre-monsoon period. The CDOM concentration was high in the middle section (January-February) and gradually decreased towards the estuary's head and mouth. The highest CDOM was found in February at locations C and D during the pre-monsoon period. Every station shows a significant correlation among CDOM, TSM, and Chl-a measured parameters. Based on our satellite data analysis, it is recommended that SNAP C2RCC be regionally used for TSM, Chl-a, and CDOM for water quality product retrieval and in various algorithms for the Hooghly estuary monitoring.


Assuntos
Monitoramento Ambiental , Qualidade da Água , Estuários , Clorofila A , Rios
14.
Sci Total Environ ; 887: 164057, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37178842

RESUMO

Hospital effluents represent a threat to the environment owing to the content of toxic substances capable of altering the structure and function of ecosystems. Despite the available information about the impact of hospital effluents on aquatic organisms, the molecular mechanism underlying this process has received little or no attention. The present study aimed to evaluate the oxidative stress and gene expression induced by different proportions (2 %, 2.5 %, 3 % and 3.5 %) of hospital effluent treated by hospital wastewater treatment plant (HWWTP) in liver, gut, and gills of Danio rerio at different exposure times. Significant increases in the levels of protein carbonylation content (PCC), hydroperoxides content (HPC), lipoperoxidation level (LPX) and superoxide dismutase (SOD) and catalase (CAT) activity were observed in most of the organs evaluated at the four proportions tested with respect to the control group (p < 0.05). It was found that at longer exposure times there is a lower response in SOD activity, suggesting catalytic depletion due to the oxidative environment at the intracellular level. The lack of complementarity between SOD and mRNA activity patterns indicates that the activity itself is subordinated to post-transcriptional processes. Upregulation of transcripts related to antioxidant processes (sod, cat, nrf2), detoxification (cyp1a1) and apoptosis (bax, casp6, and casp9) was observed in response to oxidative imbalance. On the other hand, the metataxonomic approach allowed the characterization of pathogenic bacterial genera such as Legionella, Pseudomonas, Clostridium XI, Parachlamydia and Mycobacterium present in the hospital effluent. Our findings indicate that although hospital effluent was treated by HWWTP, it caused oxidative stress damage and disrupted gene expression by decreasing the antioxidant response in Danio rerio.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Antioxidantes/metabolismo , Ecossistema , Estresse Oxidativo , Catalase/metabolismo , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/toxicidade , Hospitais , Expressão Gênica
15.
Comput Methods Programs Biomed ; 234: 107515, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37011425

RESUMO

BACKGROUND AND OBJECTIVE: Mechanical thrombectomy is a minimally invasive procedure that aims at removing the occluding thrombus from the vasculature of acute ischemic stroke patients. Thrombectomy success and failure can be studied using in-silico thrombectomy models. Such models require realistic modeling steps to be effective. We here present a new approach to model microcatheter tracking during thrombectomy. METHODS: For 3 patient-specific vessel geometries, we performed finite-element simulations of the microcatheter tracking (1) following the vessel centerline (centerline method) and (2) as a one-step insertion simulation, where the microcatheter tip was advanced along the vessel centerline while its body was free to interact with the vessel wall (tip-dragging method). Qualitative validation of the two tracking methods was performed with the patient's digital subtraction angiography (DSA) images. In addition, we compared simulated thrombectomy outcomes (successful vs unsuccessful thrombus retrieval) and maximum principal stresses on the thrombus between the centerline and tip-dragging method. RESULTS: Qualitative comparison with the DSA images showed that the tip-dragging method more realistically resembles the patient-specific microcatheter-tracking scenario, where the microcatheter approaches the vessel walls. Although the simulated thrombectomy outcomes were similar in terms of thrombus retrieval, the thrombus stress fields (and the associated fragmentation of the thrombus) were strongly different between the two methods, with local differences in the maximum principal stress curves up to 84%. CONCLUSIONS: Microcatheter positioning with respect to the vessel affects the stress fields of the thrombus during retrieval, and therefore, may influence thrombus fragmentation and retrieval in-silico thrombectomy.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Trombose , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Trombose/diagnóstico por imagem , Trombose/cirurgia , Simulação por Computador , Resultado do Tratamento
16.
Polymers (Basel) ; 15(6)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36987218

RESUMO

A significant mechanical properties mismatch between natural bone and the material forming the orthopedic implant device can lead to its failure due to the inhomogeneous loads distribution, resulting in less dense and more fragile bone tissue (known as the stress shielding effect). The addition of nanofibrillated cellulose (NFC) to biocompatible and bioresorbable poly(3-hydroxybutyrate) (PHB) is proposed in order to tailor the PHB mechanical properties to different bone types. Specifically, the proposed approach offers an effective strategy to develop a supporting material, suitable for bone tissue regeneration, where stiffness, mechanical strength, hardness, and impact resistance can be tuned. The desired homogeneous blend formation and fine-tuning of PHB mechanical properties have been achieved thanks to the specific design and synthesis of a PHB/PEG diblock copolymer that is able to compatibilize the two compounds. Moreover, the typical high hydrophobicity of PHB is significantly reduced when NFC is added in presence of the developed diblock copolymer, thus creating a potential cue for supporting bone tissue growth. Hence, the presented outcomes contribute to the medical community development by translating the research results into clinical practice for designing bio-based materials for prosthetic devices.

17.
Nurs Rep ; 13(1): 297-306, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36976680

RESUMO

BACKGROUND: A flipped classroom integrating clinical simulation has been shown to be effective for basic life support (BLS) competencies in nursing students. Cardiopulmonary arrests (CPAs) in pregnant women have a low incidence but high morbidity and mortality. Current trends show an increasing incidence; however, most official university nursing training curricula do not include specific training modules for BLS in pregnant women. This study aims to know the satisfaction and self-confidence of nursing students with respect to a training intervention regarding in BLS in pregnant women. Additionally, it aims to assess the adequacy of this intervention for acquiring the necessary knowledge on the subject. METHODS: A cross-sectional study was conducted at the University of Jaen in 2022. Data were collected on sociodemographic factors, previous contact with the topic, and topic knowledge in addition to the use of an SCLS questionnaire to measure satisfaction. Participants took the BLS training (a flipped classroom integrating clinical simulation on this topic) before answering the questionnaire. RESULTS: A total of 136 students participated. The mean score on the BLS questionnaire was 9.10 out of 10 (SD = 1.01). The mean score for the SCLS questionnaire for females was 62.36 (SD = 7.70) and 56.23 (SD = 16.94) for the male group. Age showed a statistically significant association with SCLS score: the score decreased with an increase in age (p < 0.001). CONCLUSIONS: The flipped classroom, integrating simulation for BLS in pregnant women, improves self-confidence, satisfaction, and knowledge on the topic.

18.
J Mech Behav Biomed Mater ; 140: 105707, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36801786

RESUMO

Additive manufacturing is widely used in the orthopaedic industry for the high freedom and flexibility in the design and production of personalized custom implants made of Ti6Al4V. Within this context, finite element modeling of 3D printed prostheses is a robust tool both to guide the design phase and to support clinical evaluations, possibly virtually describing the in-vivo behavior of the implant. Given realistic scenarios, a suitable description of the overall implant's mechanical behavior is unavoidable. Considering typical custom prostheses' designs (i.e. acetabular and hemipelvis implants), complex designs involving solid and/or trabeculated parts, and material distribution at different scales hinder a high-fidelity modeling of the prostheses. Moreover, uncertainties in the production and in the material characterization of small parts approaching the accuracy limit of the additive manufacturing technology still exist. While recent works suggest that the mechanical properties of thin 3D-printed parts may be peculiarly affected by specific processing parameters (i.e. powder grain size, printing orientation, samples' thickness) as compared to conventional Ti6Al4V alloy, the current numerical models make gross simplifications in describing the complex material behavior of each part at different scales. The present study focuses on two patient-specific acetabular and hemipelvis prostheses, with the aim of experimentally characterizing and numerically describing the dependency of the mechanical behavior of 3D printed parts on their peculiar scale, therefore, overcoming one major limitation of current numerical models. Coupling experimental activities with finite element analyses, the authors initially characterized 3D printed Ti6Al4V dog-bone samples at different scales, representative of the main material components of the investigated prostheses. Afterwards, the authors implemented the characterized material behaviors into finite element models to compare the implications of adopting scale-dependent vs. conventional scaleindependent approaches in predicting the experimental mechanical behavior of the prostheses in terms of their overall stiffness and the local strain distribution. The material characterization results highlighted the need for a scale-dependent reduction of the elastic modulus for thin samples compared to the conventional Ti6Al4V, which is fundamental to properly describe the overall stiffness and local strain distribution on the prostheses. The presented works demonstrate how an appropriate material characterization and a scale-dependent material description is needed to develop reliable FE models of 3D printed implants characterized by a complex material distribution at different scales.


Assuntos
Ligas , Próteses e Implantes , Animais , Cães , Análise de Elementos Finitos , Porosidade , Desenho de Prótese , Acetábulo , Impressão Tridimensional
19.
Rev. Psicol., Divers. Saúde ; 12(1)fev. 2023. tab, ilus
Artigo em Espanhol, Português | LILACS | ID: biblio-1523174

RESUMO

OBJETIVO: Comparar o engajamento acadêmico durante a pandemia de COVID-19 em estudantes de duas universidades. METODOLOGIA: Estudo quantitativo, transversal, correlacional, analítico, utilizando a escala de engajamento acadêmico. A amostra foi composta por 650 alunos de psicologia, selecionados durante o ano de 2021 de forma não aleatória por conveniência, em duas universidades da Baixa Califórnia, México, uma privada e outra pública (319 e 331 alunos respectivamente), a escola privada com experiência anterior em educação à distância, e a segunda, com implantação de educação à distância emergencial durante a pandemia do COVID-19, a coleta de dados foi realizada virtualmente por meio de questionário. RESULTADOS: os alunos da universidade com experiência em educação à distância percebem, em média, um nível de engajamento acadêmico maior do que os universitários sem experiência em educação à distância. VALOR: A transdisciplinaridade de pesquisadores-acadêmicos nas áreas de psicologia e saúde coletiva trouxe evidências sobre a importância dos aspectos psicológicos (engajamento acadêmico) em novos paradigmas de pedagogia educacional (educação à distância), em meio a grandes problemas médico-epidemiológicos (pandemia de COVID-19). CONCLUSÕES: Concluiu-se que o nível de engajamento acadêmico dos alunos está vinculado à experiência anterior em educação à distância.


| OBJECTIVE: To compare academic engagement during the COVID-19 pandemic in students from two universities. METHODOLOGY: Quantitative, cross-sectional, correlational, analytical study, using the academic engagement scale. The sample was 650 undergraduate students in psychology, selected during the year 2021 in a non-random manner for convenience at two universities in Baja California, Mexico, one private and the other public (319 and 331 students respectively), the private school with experience previous in remote education, and the public school migrated to emergency remote education during the COVID-19 pandemic, data collection was carried out virtually through a questionnaire. RESULTS: University students with experience in remote education perceive on average a higher level of academic engagement than university students without experience in remote education. VALUE: The transdisciplinarity of researchers-academics in the areas of psychology and public health, provided evidence on the importance of psychological aspects (academic engagement) in new paradigms of educational pedagogy (remote education), in the midst of major medical-epidemiological problems (COVID 19 pandemic). CONCLUSIONS: It is concluded that the level of academic engagement of the students is linked to previous experience in remote education.


OBJETIVO: Comparar el engagement académico durante la pandemia COVID-19 en estudiantes de dos universidades. METODOLOGÍA: Estudio cuantitativo, transversal, correlacional, analítico, utilizando la escala engagement académico. La muestra fue de 650 estudiantes de licenciatura en psicología, seleccionados durante el año 2021 de manera no aleatoria por conveniencia en dos universidades de Baja California, México, una privada y la otra pública (319 y 331 alumnos respectivamente), la escuela privada con experiencia previa en educación remota, y la escuela pública migró a la educación remota de emergencia durante la pandemia COVID-19, la recolección de datos se realizó de manera virtual mediante un cuestionario. RESULTADOS: Los estudiantes de la universidad con experiencia en educación remota perciben en promedio mayor nivel de engagement académico que la universidad sin experiencia en educación remota. VALOR: La transdisciplinariedad de los investigadores-académicos en las áreas de psicología y salud pública, aportó evidencia sobre la importancia de aspectos psicológicos (engagement académico) en nuevos paradigmas de la pedagogía educativa (educación remota), en medio de grandes problemas médico-epidemiológicos (pandemia por COVID 19). CONCLUSIONES: Se concluye que el nivel de engagement académico de los alumnos se vincula a la experiencia previa en educación remota.


Assuntos
COVID-19 , Psicologia , Comportamento Social
20.
Chemosphere ; 313: 137383, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36436581

RESUMO

Primary sludge (PS) is associated with public health and environmental risks, so regulations focus on reducing the pathogenic and heavy metal contents of the treated material (biosolids), intended for soil amendments and land reclamation. The regulations set limits for Escherichia coli (or fecal coliforms), Salmonella spp., helminth eggs and enterovirus. However, the potential risk due to antibiotic resistant bacteria (ARB) and other human potential pathogenic bacteria (HPB) are not considered. In this work, three sludge treatment processes, having in common an anaerobic digestion step, were applied to assess the removal of regulated bacteria (fecal coliforms, Salmonella spp), ARB and HPB. The treatment arrangements, fed with PS from a full-scale wastewater treatment plant were: 1) Mesophilic anaerobic digestion followed by alkaline stabilization post-treatment (MAD-CaO); 2) Thermophilic anaerobic digestion (TAD) and, 3) Pre-treatment (mild thermo-hydrolysis) followed by TAD (PT-TAD). The results address the identification, quantification (colony forming units) and taxonomic characterization of ARB resistant to ß-lactams and vancomycin, as well as the taxonomic characterization of HPB by sequencing with PacBio. In addition, quantification based on culture media of fecal coliforms and Salmonella spp. is presented. The capabilities and limitations of microbiological and metataxonomomic analyses based on PacBio sequencing are discussed, emphasizing that they complement each other. Genus Aeromonas, Acinetobacter, Citrobacter, Enterobacter, Escherichia, Klebsiella, Ochrobactrum, Pseudomonas and Raoultella, among others, were found in the PS, which are of clinical or environmental importance, being either HPB, HPB-ARB, or non-pathogenic ARB with the potentiality of horizontal gene transfer. Based on the analysis of fecal coliforms and Salmonella spp., the three processes produced class A (highest) biosolids, suitable for unrestricted agriculture applications. Mild thermo-hydrolisis was effective in decreasing ARB cultivability, but it reappeared after the following TAD. O. intermedium (HPB-ARB) was enriched in MAD and TAD while Laribacter hongkongensis (HPB) did persist after the applied treatments.


Assuntos
Antagonistas de Receptores de Angiotensina , Esgotos , Humanos , Esgotos/microbiologia , Anaerobiose , Hidrólise , Biossólidos , Inibidores da Enzima Conversora de Angiotensina , Bactérias , Salmonella , Escherichia coli , Resistência Microbiana a Medicamentos , Digestão , Bactérias Anaeróbias
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