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1.
Polymers (Basel) ; 16(7)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38611146

RESUMO

Cork composites are byproducts from wine stopper production, resulting from the agglomeration of cork granules with a thermoset resin. The resulting compound is a versatile and durable material with numerous industrial applications. Due to its unique properties, such as low-density, high-strength, excellent energy absorption, and good thermal and acoustic insulators, cork composites find room for application in demanding industries such as automotive, construction, and aerospace. However, agglomerated cork typically has a polyurethane matrix derived from petrochemical sources. This study focuses on developing eco-friendly porous polyurethane biocomposites manufactured with the used cooking oil polyol modified with cork. Since cork and polyurethane foam are typically used for impact shock absorption, the manufactured samples were subjected to impact loading. The assessment of crashworthiness is performed through 100 J impact tests. A finite element numerical model was developed to simulate the compression of these new composites under impact, and the model validation was performed. The highest specific absorbed energy was obtained for petrochemical polyol composites with the 3% addition of natural or modified cork. The research conducted in this study showcased the feasibility of substituting certain petrochemical components used for the synthesis of the polyurethane matrix with ecological waste vegetable oil components.

2.
Adv Colloid Interface Sci ; 327: 103157, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38626554

RESUMO

Shear thickening fluids (STFs) are a unique type of fluids that can quickly transform into a solid-like state when subjected to forces (rate dependent). These fluids are created by dispersing micro and nanoparticles within a medium. When the force is removed, they return to their original liquid state. Shear thickening fluids can absorb a significant amount of impact energy, making them useful for reducing vibrations and serving as a damper. This study provides a comprehensive and brief overview of existing literature on shear thickening fluids, including their properties, classification, and the rheological mechanisms behind the shear thickening behaviour. It also examines the use of these fluids in various applications, such as improving resistance to stabs and spikes, protecting against low- and high-velocity impacts, and as a new medium for energy dissipation in industries such as battery safety, vibration control and adaptive structures. Lastly, this work reviews the promising combination of STFs with cork. Given the sustainability of cork and its energy absorption capacity, cork-STF composites are a promising solution for various impact-absorbing applications. Overall, the paper underscores the versatility and potential of STFs, and advocates for further research and exploration.

3.
PLoS One ; 19(2): e0278738, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359001

RESUMO

OBJECTIVES: To identify and describe the profile of potential transthyretin cardiac amyloidosis (ATTR-CM) cases in the Brazilian public health system (SUS), using a predictive machine learning (ML) model. METHODS: This was a retrospective descriptive database study that aimed to estimate the frequency of potential ATTR-CM cases in the Brazilian public health system using a supervised ML model, from January 2015 to December 2021. To build the model, a list of ICD-10 codes and procedures potentially related with ATTR-CM was created based on literature review and validated by experts. RESULTS: From 2015 to 2021, the ML model classified 262 hereditary ATTR-CM (hATTR-CM) and 1,581 wild-type ATTR-CM (wtATTR-CM) potential cases. Overall, the median age of hATTR-CM and wtATTR-CM patients was 66.8 and 59.9 years, respectively. The ICD-10 codes most presented as hATTR-CM and wtATTR-CM were related to heart failure and arrythmias. Regarding the therapeutic itinerary, 13% and 5% of hATTR-CM and wtATTR-CM received treatment with tafamidis meglumine, respectively, while 0% and 29% of hATTR-CM and wtATTR-CM were referred to heart transplant. CONCLUSION: Our findings may be useful to support the development of health guidelines and policies to improve diagnosis, treatment, and to cover unmet medical needs of patients with ATTR-CM in Brazil.


Assuntos
Neuropatias Amiloides Familiares , Amiloidose , Cardiomiopatias , Humanos , Brasil/epidemiologia , Pré-Albumina , Saúde Pública , Estudos Retrospectivos , Aprendizado de Máquina , Cardiomiopatias/diagnóstico , Cardiomiopatias/epidemiologia , Neuropatias Amiloides Familiares/diagnóstico , Neuropatias Amiloides Familiares/epidemiologia
4.
Cureus ; 16(1): e51432, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38298291

RESUMO

A 57-year-old male, with chronic bilateral knee pain and a history of poorly controlled hyperuricemia leading to gouty attacks, underwent orthopedic assessment. Radiographic and MRI findings confirmed chronic gouty arthropathy with erosive bony defects, the most significant on the right proximal tibia. Total knee arthroplasty (TKA) was performed without any complications, addressing the bony defect with cement and a semi-constrained prosthesis. However, a gouty attack led to prolonged wound discharge and periprosthetic infection postoperatively, prompting revision surgery with debridement, antibiotics, and implant retention (DAIR). Intraoperative cultures revealed methicillin-sensitive Staphylococcus aureus (MSSA). The treatment included vancomycin and rifampicin. Two years post-surgery, the patient walked pain-free with a knee range of motion of 0-90º. This report highlights the complexity of treating gout-related knee osteoarthritis, emphasizing early intervention to mitigate risks of extensive surgical procedures and infections.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38243591

RESUMO

BACKGROUND: Although impaired left ventricular (LV) global longitudinal strain (GLS) with apical sparing is a feature of cardiac amyloidosis (CA), its diagnostic accuracy has varied across studies. We aimed to determine the ability of apical sparing ratio (ASR) and most common echocardiographic parameters to differentiate patients with confirmed CA from those with clinical and/or echocardiographic suspicion of CA, but with this diagnosis ruled out. METHODS: We identified 544 patients with confirmed CA and 200 controls as defined above (CTRL Patients). Measurements from transthoracic echocardiograms (TTE) were performed using artificial intelligence software (Us2.AI, Singapore) and audited by an experienced echocardiographer. Receiver-operating characteristic curve analysis was used to evaluate the diagnostic performance and optimal cutoffs for the differentiation of CA patients from CTRL Patients. Additionally, a group of 174 healthy subjects (Healthy CTRL) was included to provide insight on how Patients and Healthy controls differed echocardiographically. RESULTS: LV GLS was more impaired (-13.9 ± 4.6% vs -15.9 ± 2.7%, p < 0.0005) and ASR was higher (2.4 ± 1.2 vs 1.7 ± 0.9, p < 0.0005) in the CA group vs. CTRL Patients. Relative wall thickness and ASR were the most accurate parameters for differentiating CA from CTRL Patients (AUC: 0.77 and 0.74, respectively). However, even with the optimal cutoff of 1.67, ASR was only 72% sensitive and 66% specific for CA, indicating presence of apical sparing in 32% of CTRL Patients and even in 6% Healthy CTRLs. CONCLUSIONS: Apical sparing did not prove to be a CA-specific biomarker for accurate identification of CA, when compared to clinically similar controls with no CA.

6.
JAMA Cardiol ; 9(1): 25-34, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37966817

RESUMO

Importance: Tafamidis has been shown to improve survival in patients with transthyretin amyloid cardiomyopathy (ATTR-CM) compared with placebo. However, its effect on cardiac function has not been fully characterized. Objective: To examine the effect of tafamidis on cardiac function in patients with ATTR-CM. Design, Setting, and Participants: This was an exploratory, post hoc analysis of the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT), a multicenter, international, double-blind, placebo-controlled phase 3 randomized clinical trial conducted from December 2013 to February 2018. The ATTR-ACT included 48 sites in 13 counties and enrolled patients aged 18 to 90 years with ATTR-CM. Data were analyzed from July 2018 to September 2023. Intervention: Patients were randomized to tafamidis meglumine, 80 mg or 20 mg, or placebo for 30 months. Main Outcomes and Measures: Patients were categorized based on left ventricular (LV) ejection fraction at enrollment as having heart failure with preserved ejection fraction (≥50%), mildly reduced ejection fraction (41% to 49%), or reduced ejection fraction (≤40%). Changes from baseline to month 30 in LV ejection fraction, LV stroke volume, LV global longitudinal strain, and the ratio of early mitral inflow velocity to septal and lateral early diastolic mitral annular velocity (E/e') were compared in patients receiving tafamidis, 80 mg, vs placebo. Results: A total of 441 patients were randomized in ATTR-ACT, and 436 patients had available echocardiographic data. Of 436 included patients, 393 (90.1%) were male, and the mean (SD) age was 74 (7) years. A total of 220 (50.5%), 119 (27.3%), and 97 (22.2%) had heart failure with preserved, mildly reduced, and reduced LV ejection fraction, respectively. Over 30 months, there was less pronounced worsening in 4 of the echocardiographic measures in patients receiving tafamidis, 80 mg (n = 176), vs placebo (n = 177) (least squares mean difference: LV stroke volume, 7.02 mL; 95% CI, 2.55-11.49; P = .002; LV global longitudinal strain, -1.02%; 95% CI, -1.73 to -0.31; P = .005; septal E/e', -3.11; 95% CI, -5.50 to -0.72; P = .01; lateral E/e', -2.35; 95% CI, -4.01 to -0.69; P = .006). Conclusions and Relevance: Compared with placebo, tafamidis, 80 mg, attenuated the decline of LV systolic and diastolic function over 30 months in patients with ATTR-CM. Approximately half of patients had mildly reduced or reduced LV ejection fraction at enrollment, suggesting that ATTR-CM should be considered as a possible diagnosis in patients with heart failure regardless of underlying LV ejection fraction. Trial Registration: ClinicalTrials.gov Identifier: NCT01994889.


Assuntos
Amiloidose , Cardiomiopatias , Insuficiência Cardíaca , Disfunção Ventricular Esquerda , Feminino , Humanos , Masculino , Cardiomiopatias/tratamento farmacológico , Insuficiência Cardíaca/tratamento farmacológico , Pré-Albumina , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
7.
J. bras. econ. saúde (Impr.) ; 15(3): 190-199, Dezembro/2023.
Artigo em Inglês, Português | LILACS-Express | LILACS | ID: biblio-1553993

RESUMO

Objective: To generate data on the costs associated with the diagnosis and treatment of obstructive ypertrophic cardiomyopathy (HCM) from the perspective of the private health system in Brazil. Methods: A modified Delphi panel including seven different specialists (three clinical cardiologists with experience in obstructive HCM, two hemodynamicists with experience in septal ablation and two cardiac surgeons with expertise in myectomy), from two Brazilian states (São Paulo and Pernambuco), was conducted between August and November 2022. Two rounds of questions about the use of healthcare resources according to the functional class (NYHA I-IV) and a panel in a virtual platform were conducted to obtain the final consensus. Micro-costing defined costs and unit values were determined based on official price lists. Results: The total diagnosis cost per patient was estimated at BRL 11,486.81. The obstructive HCM management costs analysis showed average annual costs per patient of BRL 17,026.74, BRL 19,401.46, BRL 73,310.07, and BRL 94,885.75 for the functional classes NYHA I, NYHA II, NYHA III, and NYHA IV, respectively. The average costs per patient related to procedures in a year were BRL 12,698.53, BRL 13,462.30, BRL 58,841.67, and BRL 75,595.90 for the functional classes NYHA I, II, III, and IV, respectively. Conclusions: The annual costs of HCM management increased according to the functional class, highlighting the need for safe and effective strategies to improve patient's NYHA functional class while promoting a decrease in the need for invasive therapies.


Objetivo: Gerar dados acerca dos custos associados ao diagnóstico e tratamento da cardiomiopatia hipertrófica (CMH) obstrutiva, sob a perspectiva do sistema de saúde privado no Brasil. Métodos: Um painel Delphi modificado incluindo sete especialistas (três cardiologistas clínicos com experiência em CMH obstrutiva, dois hemodinamicistas com experiência em ablação de septo e dois cirurgiões cardíacos com experiência em miectomia) de dois estados brasileiros (São Paulo e Pernambuco) foi conduzido entre agosto e novembro de 2022. Foram realizadas duas rodadas de perguntas acerca da utilização de recursos de acordo com a classe funcional (NYHA I-IV) e uma reunião virtual para obtenção do consenso final. Os custos foram definidos por meio de microcusteio, e os valores unitários foram definidos com base em listas de preço oficiais. Resultados: O custo total do diagnóstico por paciente foi estimado em R$ 11.486,81. A análise de custos de manejo da CMH obstrutiva mostrou custos médios anuais por paciente de R$ 17.026,74, R$ 19.401,46, R$ 73.310,07 e R$ 94.885,75 para as classes funcionais NYHA I, NYHA II, NYHA III e NYHA IV, respectivamente. Os custos médios por paciente relacionados a procedimentos em um ano foram de R$ 12.698,53, R$ 13.462,30, R$ 58.841,67 e R$ 75.595,90 para as classes NYHA I, II, III e IV, respectivamente. Conclusões: Os custos anuais com o manejo da CMH aumentam de acordo com a classe funcional, destacando a necessidade de estratégias seguras e eficazes capazes de melhorar a classe funcional NYHA do paciente, ao mesmo tempo que promove diminuição da necessidade de terapias invasivas.

8.
Materials (Basel) ; 16(24)2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38138655

RESUMO

Metal additive manufacturing (AM) is a layer-by-layer process that makes the direct manufacturing of various industrial parts possible. This method facilitates the design and fabrication of complex industrial, advanced, and fine parts that are used in different industry sectors, such as aerospace, medicine, turbines, and jewelry, where the utilization of other fabrication techniques is difficult or impossible. This method is advantageous in terms of dimensional accuracy and fabrication speed. However, the parts fabricated by this method may suffer from faults such as anisotropy, micro-porosity, and defective joints. Metals like titanium, aluminum, stainless steels, superalloys, etc., have been used-in the form of powder or wire-as feed materials in the additive manufacturing of various parts. The main criterion that distinguishes different additive manufacturing processes from each other is the deposition method. With regard to this criterion, AM processes can be divided into four classes: local melting, sintering, sheet forming, and electrochemical methods. Parameters affecting the properties of the additive-manufactured part and the defects associated with an AM process determine the method by which a certain part should be manufactured. This study is a survey of different additive manufacturing processes, their mechanisms, capabilities, shortcomings, and the general properties of the parts manufactured by them.

9.
Autops Case Rep ; 13: e2023449, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38034520

RESUMO

Giant cell arteritis (GCA) is a type of chronic vasculitis that affects medium and large-caliber arteries, frequently related to aortic involvement and, consequently, to aneurysm formation. However, associated valvulitis with giant cells is uncommon. We describe the case of a 50-year-old female patient with aortic aneurysm and valvular insufficiency, whose anatomopathological examination revealed giant-cell aortic valvulitis associated with giant cell aortitis.

10.
N Engl J Med ; 389(17): 1553-1565, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37888916

RESUMO

BACKGROUND: Transthyretin amyloidosis, also called ATTR amyloidosis, is associated with accumulation of ATTR amyloid deposits in the heart and commonly manifests as progressive cardiomyopathy. Patisiran, an RNA interference therapeutic agent, inhibits the production of hepatic transthyretin. METHODS: In this phase 3, double-blind, randomized trial, we assigned patients with hereditary, also known as variant, or wild-type ATTR cardiac amyloidosis, in a 1:1 ratio, to receive patisiran (0.3 mg per kilogram of body weight) or placebo once every 3 weeks for 12 months. A hierarchical procedure was used to test the primary and three secondary end points. The primary end point was the change from baseline in the distance covered on the 6-minute walk test at 12 months. The first secondary end point was the change from baseline to month 12 in the Kansas City Cardiomyopathy Questionnaire-Overall Summary (KCCQ-OS) score (with higher scores indicating better health status). The second secondary end point was a composite of death from any cause, cardiovascular events, and change from baseline in the 6-minute walk test distance over 12 months. The third secondary end point was a composite of death from any cause, hospitalizations for any cause, and urgent heart failure visits over 12 months. RESULTS: A total of 360 patients were randomly assigned to receive patisiran (181 patients) or placebo (179 patients). At month 12, the decline in the 6-minute walk distance was lower in the patisiran group than in the placebo group (Hodges-Lehmann estimate of median difference, 14.69 m; 95% confidence interval [CI], 0.69 to 28.69; P = 0.02); the KCCQ-OS score increased in the patisiran group and declined in the placebo group (least-squares mean difference, 3.7 points; 95% CI, 0.2 to 7.2; P = 0.04). Significant benefits were not observed for the second secondary end point. Infusion-related reactions, arthralgia, and muscle spasms occurred more often among patients in the patisiran group than among those in the placebo group. CONCLUSIONS: In this trial, administration of patisiran over a period of 12 months resulted in preserved functional capacity in patients with ATTR cardiac amyloidosis. (Funded by Alnylam Pharmaceuticals; APOLLO-B ClinicalTrials.gov number, NCT03997383.).


Assuntos
Amiloidose , Cardiomiopatias , Pré-Albumina , RNA Interferente Pequeno , Humanos , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/etiologia , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Pré-Albumina/genética , Pré-Albumina/metabolismo , RNA Interferente Pequeno/uso terapêutico , Amiloidose Familiar/complicações , Amiloidose Familiar/tratamento farmacológico , Amiloidose Familiar/genética , Fígado/metabolismo , Método Duplo-Cego , Amiloidose/complicações , Amiloidose/tratamento farmacológico , Amiloidose/genética
11.
Front Cardiovasc Med ; 10: 1121083, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37588035

RESUMO

Introduction: The role of myocardial strain in risk prediction for acute myocarditis (AMC) patients, measured by cardiac magnetic resonance (CMR), deserves further investigation. Our objective was to evaluate the association between myocardial strain measured by CMR and clinical events in AMC patients. Material and methods: This was a prospective single-center study of patients with AMC. We included 100 patients with AMC with CMR confirmation. The primary outcome was the composite of all-cause mortality, heart failure and AMC recurrence in 24 months. A subgroup analysis was performed on a sample of 36 patients who underwent a second CMR between 6 and 18 months. The association between strain measures and clinical events or an increase in left ventricular ejection fraction (LVEF) was explored using Cox regression analysis. Global peak radial, circumferential and longitudinal strain in the left and right ventricles was assessed. ROC curve analysis was performed to identify cutoff points for clinical event prediction. Results: The mean follow-up was 18.7 ± 2.3 months, and the composite primary outcome occurred in 26 patients. The median LVEF at CMR at baseline was 57.5% (14.6%). LV radial strain (HR = 0.918, 95% CI: 0.858-0.982, p = 0.012), LV circumferential strain (HR = 1.177, 95% CI: 1.046-1.325, p = 0.007) and LV longitudinal strain (HR = 1.173, 95% CI: 1.031-1.334, p = 0.015) were independently associated with clinical event occurrence. The areas under the ROC curve for clinical event prediction were 0.80, 0.79 and 0.80 for LV radial, circumferential, and longitudinal strain, respectively. LV longitudinal strain was independently correlated with prognosis (HR = 1.282, CI 95%: 1.022-1.524, p = 0.007), even when analyzed together with ejection fraction and delayed enhancement. LV and right ventricle (RV) strain were not associated with an increase in LVEF. Finally, when the initial CMR findings were compared with the follow-up CMR findings, improvements in the measures of LV and RV myocardial strain were observed. Conclusion: Measurement of myocardial strain by CMR can provide prognostic information on AMC patients. LV radial, circumferential and longitudinal strain were associated with long-term clinical events in these patients.

12.
Radiol Cardiothorac Imaging ; 5(3): e220112, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37404789

RESUMO

Purpose: To evaluate myocardial T1 mapping and extracellular volume (ECV) parameters in different stages of Chagas cardiomyopathy and determine whether they are predictive of disease severity and prognosis. Materials and Methods: Prospectively enrolled participants (July 2013 to September 2016) underwent cine and late gadolinium enhancement (LGE) cardiac MRI and T1 mapping with a precontrast (native) or postcontrast modified Look-Locker sequence. The native T1 and ECV values were measured among subgroups that were based on disease severity (indeterminate, Chagas cardiomyopathy with preserved ejection fraction [CCpEF], Chagas cardiomyopathy with midrange ejection fraction [CCmrEF], and Chagas cardiomyopathy with reduced ejection fraction [CCrEF]). Cox proportional hazards regression and the Akaike information criterion were used to determine predictors of major cardiovascular events (cardioverter defibrillator implant, heart transplant, or death). Results: In 107 participants (90 participants with Chagas disease [mean age ± SD, 55 years ± 11; 49 men] and 17 age- and sex-matched control participants), the left ventricular (LV) ejection fraction and the extent of focal and diffuse or interstitial fibrosis were correlated with disease severity. Participants with CCmrEF and participants with CCrEF showed significantly higher global native T1 and ECV values than participants in the indeterminate, CCpEF, and control groups (T1: 1072 msec ± 34 and 1073 msec ± 63 vs 1010 msec ± 41, 1005 msec ± 69, and 999 msec ± 46; ECV: 35.5% ± 3.6 and 35.0% ± 5.4 vs 25.3% ± 3.5, 28.2% ± 4.9, and 25.2% ± 2.2; both P < .001). Remote (LGE-negative areas) native T1 and ECV values were also higher (T1: 1056 msec ± 32 and 1071 msec ± 55 vs 1008 msec ± 41, 989 msec ± 96, and 999 msec ± 46; ECV: 30.2% ± 4.7 and 30.8% ± 7.4 vs 25.1% ± 3.5, 25.1% ± 3.7, and 25.0% ± 2.2; both P < .001). Abnormal remote ECV values (>30%) occurred in 12% of participants in the indeterminate group, which increased with disease severity. Nineteen combined outcomes were observed (median follow-up time: 43 months), and a remote native T1 value greater than 1100 msec was independently predictive of combined outcomes (hazard ratio, 12 [95% CI: 4.1, 34.2]; P < .001). Conclusion: Myocardial native T1 and ECV values were correlated with Chagas disease severity and may serve as markers of myocardial involvement in Chagas cardiomyopathy that precede LGE and LV dysfunction.Keywords: MRI, Cardiac, Heart, Imaging Sequences, Chagas Cardiomyopathy Supplemental material is available for this article. © RSNA, 2023.

13.
J Safety Res ; 85: 254-265, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37330875

RESUMO

INTRODUCTION: The paper addresses an important accident type that involves children in bicycle seats - the bicycle fall over. It is a significant and common accident type and many parents have been reported to experience this type of "close call." The fall over occurs at low velocities and even while a bicycle is standing still, and may result from a split-second lack of attention on behalf of the accompanying adult (e.g. while loading groceries, i.e. while not being exposed to traffic per se). Moreover, irrespective of the low velocities involved, the trauma that may result to the head of the child is considerable and may be life-threatening, as shown in the study. METHOD: The paper presents two methods to address this accident scenario in a quantitative way: in-situ accelerometer-based measurement and numerical modeling approaches. It is shown that the methods produce consistent results under the prerequisites of the study. They are therefore promising methods to be used in the study of this type of accident. RESULTS: The importanance of the protective role of a child helmet is without discussion in everyday traffic.However, this study draws attention to one particular effect observed in this accident type: that the geometry of the helmet may at times expose the child's head to considerably larger forces, by having contact with the ground. The study also highlights the importance of neck bending injuries during bicycle fall over, which are often neglected in the safety assessment - not only for children in bicycle seats. The study concludes that considering only head acceleration may lead to biased conclusions about using helmets as protective devices.


Assuntos
Traumatismos Craniocerebrais , Lactente , Adulto , Criança , Humanos , Traumatismos Craniocerebrais/etiologia , Traumatismos Craniocerebrais/prevenção & controle , Ciclismo/lesões , Pais , Dispositivos de Proteção da Cabeça , Equipamentos de Proteção
14.
Pharmaceutics ; 15(6)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37376186

RESUMO

Extracellular vesicles (EVs) comprise a broad range of secreted cell-derived membrane vesicles. Beyond their more well-characterized role in cell communication, in recent years, EVs have also been shown to play important roles during infection. Viruses can hijack the biogenesis of exosomes (which are small EVs) to promote viral spreading. Additionally, these exosomes are also important mediators in inflammation and immune responses during both bacterial and viral infections. This review summarizes these mechanisms while also describing the impact of bacterial EVs in regulating immune responses. Finally, the review also focuses on the potential and challenges of using EVs, in particular, to tackle infectious diseases.

15.
Materials (Basel) ; 16(8)2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37109868

RESUMO

Renewable materials are materials that are replenished naturally and can be used again and again. These materials include things such as bamboo, cork, hemp, and recycled plastic. The use of renewable components helps to reduce the dependence on petrochemical resources and reduce waste. Adopting these materials in various industries such as construction, packaging, and textiles can lead to a more sustainable future and decrease the carbon footprint. The presented research describes new porous polyurethane biocomposites based on used cooking oil polyol (50 per hundred polyol-php) modified with cork (3, 6, 9, and 12 php). The research described here demonstrated that it is possible to replace some petrochemical raw materials with raw materials of renewable origin. This was achieved by replacing one of the petrochemical components used for the synthesis of the polyurethane matrix with a waste vegetable oil component. The modified foams were analyzed in terms of their apparent density, coefficient of thermal conductivity, compressive strength at 10% of deformation, brittleness, short-term water absorption, thermal stability, and water vapor permeability, while their morphology was examined using scanning electron microscopy and the content of closed cells. After the successful introduction of a bio-filler, it was found that the thermal insulation properties of the modified biomaterials were comparable to those of the reference material. It was concluded that it is possible to replace some petrochemical raw materials with raw materials of renewable origin.

16.
J Mech Behav Biomed Mater ; 142: 105797, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37058864

RESUMO

Although the cervical spine supports and controls the kinematics of the head, it is vulnerable to injuries during mechanical loading. Severe injuries often result in damage to the spinal cord, leading to significant ramifications. The role of gender in determining the outcome of such injuries has been established as significant. In order to better understand the essential mechanics and develop treatments or preventative measures, various forms of research have been conducted. Computational modelling is one of the most useful and extensively utilised methods, as it provides information that would otherwise be difficult to obtain. As such, the primary goal of this research is to create a new finite element of the female cervical spine that will more accurately represent the group most affected by such injuries. This work is a continuation of a previous study where a model was created from the computer tomography scans of a 46-year-old female. A functioning spinal unit consisting of the C6-C7 segment was simulated as a validation procedure. The experimental data obtained from cadaveric specimens, that assessed the range of motion of different cervical segments in flexion-extension, axial rotation, and lateral bending, was used to validate the reduced model.


Assuntos
Vértebras Cervicais , Medula Espinal , Humanos , Feminino , Pessoa de Meia-Idade , Análise de Elementos Finitos , Vértebras Cervicais/diagnóstico por imagem , Amplitude de Movimento Articular , Fenômenos Biomecânicos , Rotação
17.
Comput Methods Programs Biomed ; 231: 107430, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36827824

RESUMO

BACKGROUND AND OBJECTIVE: Traumatic brain injuries are one of the leading causes of death and disability in the world. To better understand the interactions and forces applied in different constituents of the human head, several finite element head models have been developed throughout the years, for offering a good cost-effective and ethical approach compared to experimental tests. Once validated, the female finite element head model (FeFEHM) will allow a better understanding of injury mechanisms resulting in neuronal damage, which can later evolve into neurodegenerative diseases. METHODS: This work encompasses the approached methodology starting from medical images and finite element modelling until the validation process using novel experimental data of brain displacements conducted on human cadavers. The material modelling of the brain is performed using an age-specific characterization of the brain using microindentation at dynamic rates and under large deformation, with a similar age to the patient used to model the FeFEHM. RESULTS: The numerical displacement curves are in good accordance with the experimental data, displaying similar peak times and values, in all three anatomical planes. The case study result shows a similarity between the pressure fields of the FeFEHM compared to another model, highlighting the future potential of the model. CONCLUSIONS: The initial objective was met, and a new female finite element head model has been developed with biofidelic brain motion. This model will be used for the assessment of repetitive impact scenarios and its repercussions on the female brain.


Assuntos
Lesões Encefálicas Traumáticas , Traumatismos Craniocerebrais , Feminino , Humanos , Análise de Elementos Finitos , Cabeça , Encéfalo/fisiologia , Traumatismos Craniocerebrais/etiologia , Lesões Encefálicas Traumáticas/complicações , Fenômenos Biomecânicos
18.
Biology (Basel) ; 12(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36671775

RESUMO

The biomechanics of traumatic injuries of the human body as a consequence of road crashes, falling, contact sports, and military environments have been studied for decades. In particular, traumatic brain injury (TBI), the so-called "silent epidemic", is the traumatic insult responsible for the greatest percentage of death and disability, justifying the relevance of this research topic. Despite its great importance, only recently have research groups started to seriously consider the sex differences regarding the morphology and physiology of women, which differs from men and may result in a specific outcome for a given traumatic event. This work aims to provide a summary of the contributions given in this field so far, from clinical reports to numerical models, covering not only the direct injuries from inertial loading scenarios but also the role sex plays in the conditions that precede an accident, and post-traumatic events, with an emphasis on neuroendocrine dysfunctions and chronic traumatic encephalopathy. A review on finite element head models and finite element neck models for the study of specific traumatic events is also performed, discussing whether sex was a factor in validating them. Based on the information collected, improvement perspectives and future directions are discussed.

19.
Eur Heart J Cardiovasc Imaging ; 24(6): 829-837, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36624559

RESUMO

AIMS: While cardiac magnetic resonance (CMR) is often obtained early in the evaluation of suspected cardiac amyloidosis (CA), it currently cannot be utilized to differentiate immunoglobulin (AL) and transthyretin (ATTR) CA. We aimed to determine whether a novel CMR and light-chain biomarker-based algorithm could accurately diagnose ATTR-CA. METHODS AND RESULTS: Patients with confirmed AL or ATTR-CA with typical late gadolinium enhancement (LGE) and Look-Locker pattern for CA on CMR were retrospectively identified at three academic medical centres. Comprehensive light-chain analysis including free light chains, serum, and urine electrophoresis/immunofixation was performed. The diagnostic accuracy of the typical CMR pattern for CA in combination with negative light chains for the diagnosis of ATTR-CA was determined both in the entire cohort and in the subset of patients with invasive tissue biopsy as the gold standard. A total of 147 patients (age 70 ± 11, 76% male, 51% black) were identified: 89 ATTR-CA and 58 AL-CA. Light-chain biomarkers were abnormal in 81 (55%) patients. Within the entire cohort, the sensitivity and specificity of a typical LGE and Look-Locker CMR pattern and negative light chains for ATTR-CA was 73 and 98%, respectively. Within the subset with biopsy-confirmed subtype, the CMR and light-chain algorithm were 69% sensitive and 98% specific. CONCLUSION: The combination of a typical LGE and Look-Locker pattern on CMR with negative light chains is highly specific for ATTR-CA. The successful non-invasive diagnosis of ATTR-CA using CMR has the potential to reduce diagnostic and therapeutic delays and healthcare costs for many patients.


Assuntos
Amiloidose , Cardiomiopatias , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Meios de Contraste , Gadolínio , Estudos Retrospectivos , Pré-Albumina , Amiloidose/diagnóstico , Espectroscopia de Ressonância Magnética , Cardiomiopatias/patologia
20.
Autops. Case Rep ; 13: e2023449, 2023. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1520268

RESUMO

ABSTRACT Giant cell arteritis (GCA) is a type of chronic vasculitis that affects medium and large-caliber arteries, frequently related to aortic involvement and, consequently, to aneurysm formation. However, associated valvulitis with giant cells is uncommon. We describe the case of a 50-year-old female patient with aortic aneurysm and valvular insufficiency, whose anatomopathological examination revealed giant-cell aortic valvulitis associated with giant cell aortitis.

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