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1.
Heliyon ; 10(9): e26674, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707392

RESUMO

Little is known about the simultaneous effects of non-pharmacological interventions (NPI) on healthy older adults' behavior and brain plasticity, as measured by psychometric instruments and magnetic resonance imaging (MRI). The purpose of this scoping review was to compile an extensive list of randomized controlled trials published from January 1, 2000, to August 31, 2023, of NPI for mitigating and countervailing age-related physical and cognitive decline and associated cerebral degeneration in healthy elderly populations with a mean age of 55 and over. After inventorying the NPI that met our criteria, we divided them into six classes: single-domain cognitive, multi-domain cognitive, physical aerobic, physical non-aerobic, combined cognitive and physical aerobic, and combined cognitive and physical non-aerobic. The ultimate purpose of these NPI was to enhance individual autonomy and well-being by bolstering functional capacity that might transfer to activities of daily living. The insights from this study can be a starting point for new research and inform social, public health, and economic policies. The PRISMA extension for scoping reviews (PRISMA-ScR) checklist served as the framework for this scoping review, which includes 70 studies. Results indicate that medium- and long-term interventions combining non-aerobic physical exercise and multi-domain cognitive interventions best stimulate neuroplasticity and protect against age-related decline and that outcomes may transfer to activities of daily living.

2.
bioRxiv ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38659897

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a morbid fibrotic lung disease with limited treatment options. The pathophysiology of IPF remains poorly understood, and elucidation of the cellular and molecular mechanisms of IPF pathogenesis is key to the development of new therapeutics. B-1 cells are an innate B cell population which play an important role linking innate and adaptive immunity. B-1 cells spontaneously secrete natural IgM and prevent inflammation in several disease states. One class of these IgM recognize oxidation-specific epitopes (OSE), which have been shown to be generated in lung injury and to promote fibrosis. A main B-1 cell reservoir is the pleural space, adjacent to the typical distribution of fibrosis in IPF. In this study, we demonstrate that B-1 cells are recruited to the lung during injury where they secrete IgM to OSE (IgM OSE ). We also show that the pleural B-1 cell reservoir responds to lung injury through regulation of the chemokine receptor CXCR4. Mechanistically we show that the transcription factor Id3 is a novel negative regulator of CXCR4 expression. Using mice with B-cell specific Id3 deficiency, a model of increased B-1b cells, we demonstrate decreased bleomycin-induced fibrosis compared to littermate controls. Furthermore, we show that mice deficient in secretory IgM ( sIgM -/- ) have higher mortality in response to bleomycin-induced lung injury, which is partially mitigated through airway delivery of the IgM OSE E06. Additionally, we provide insight into potential mechanisms of IgM in attenuation of fibrosis through RNA sequencing and pathway analysis, highlighting complement activation and extracellular matrix deposition as key differentially regulated pathways.

3.
BMC Complement Med Ther ; 24(1): 141, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575952

RESUMO

BACKGROUND: The optimal stimulation for brain development in the early academic years remains unclear. Current research suggests that musical training has a more profound impact on children's executive functions (EF) compared to other art forms. What is crucially lacking is a large-scale, long-term genuine randomized controlled trial (RCT) in cognitive neuroscience, comparing musical instrumental training (MIP) to another art form, and a control group (CG). This study aims to fill this gap by using machine learning to develop a multivariate model that tracks the interconnected brain and EF development during the academic years, with or without music or other art training. METHODS: The study plans to enroll 150 children aged 6-8 years and randomly assign them to three groups: Orchestra in Class (OC), Visual Arts (VA), and a control group (CG). Anticipating a 30% attrition rate, each group aims to retain at least 35 participants. The research consists of three analytical stages: 1) baseline analysis correlating EF, brain data, age, gender, and socioeconomic status, 2) comparison between groups and over time of EF brain and behavioral development and their interactions, including hypothesis testing, and 3) exploratory analysis combining behavioral and brain data. The intervention includes intensive art classes once a week, and incremental home training over two years, with the CG receiving six annual cultural outings. DISCUSSION: This study examines the potential benefits of intensive group arts education, especially contrasting music with visual arts, on EF development in children. It will investigate how artistic enrichment potentially influences the presumed typical transition from a more unified to a more multifaceted EF structure around age eight, comparing these findings against a minimally enriched active control group. This research could significantly influence the incorporation of intensive art interventions in standard curricula. TRIAL REGISTRATION: The project was accepted after peer-review by the Swiss National Science Foundation (SNSF no. 100014_214977) on March 29, 2023. The study protocol received approval from the Cantonal Commission for Ethics in Human Research of Geneva (CCER, BASEC-ID 2023-01016), which is part of Swiss ethics, on October 25, 2023. The study is registered at clinicaltrials.gov (NCT05912270).


Assuntos
Música , Criança , Humanos , Pré-Escolar , Música/psicologia , Função Executiva , Encéfalo , Projetos de Pesquisa , Cognição/fisiologia
4.
Artigo em Inglês | MEDLINE | ID: mdl-38440159

RESUMO

INTRODUCTION: Research in low- and middle-income countries (LMICs), where the majority of global tobacco users reside, is critical to addressing the global tobacco epidemic. This analysis describes the global tobacco control research portfolio funded by the National Cancer Institute from fiscal years 2000 to 2019. METHODS: We used the National Institutes of Health Query, View, Report database to identify extramural grants relevant to global tobacco control research. Abstracts were analyzed to describe grant characteristics, including topic areas, tobacco products, countries, and regions of focus. Bibliometric and co-authorship network analyses were performed for publications associated with relevant grants. RESULTS: Of the 93 relevant grants with foreign (non-US) involvement, the majority (83.9%) supported research in upper and lower middle-income countries. The majority of grants (86.0%) focused on cigarettes, with a small subset of grants addressing smokeless tobacco, waterpipe use, or other non-cigarette products. Most grants focused on at least one of the six tobacco control policy measures in the World Health Organization MPOWER package; almost half (48.4%) focused on monitoring tobacco use and around one-third (32.3%) focused on offering tobacco cessation treatment, while other MPOWER measures received less attention in the research portfolio. While most of these grants, and the funding initiatives that supported them, emphasized research in low- and middle-income countries (LMICs), only 3 of 93 grants were awarded directly to LMIC-based institutions. CONCLUSIONS: There is a critical need for research to develop and test strategies to adapt, implement, and scale up evidence-based interventions across diverse LMIC settings. This study identified gaps in research activity that should be addressed to strengthen global tobacco control research capacity.

5.
Animals (Basel) ; 14(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38473157

RESUMO

BACKGROUND: Myxomatous mitral valve degeneration is the most common canine heart disease. Several clinical trials have investigated various treatments. The latest recommendations are published in the ACVIM consensus guidelines (2019). Our study aimed to investigate how closely veterinary practitioners apply the treatment recommendations of these guidelines and the latest clinical trials. METHODS: An online survey was sent to Dutch and Belgian veterinary practices via digital channels. RESULTS: The data from 363 fully completed surveys were analyzed. For stage B1 disease, 93% recommended, correctly, no treatment. For stage B2 disease, 67% of the respondents recommended starting pimobendan as monotherapy. For chronic treatment of stage C disease, 16 different drug combinations were mentioned, but nobody recommended surgery. Only 48% of the respondents recommended the only evidence-based drug combination: a loop diuretic with pimobendan. A concerning finding was the simultaneous prescription of two loop diuretics, by 19% of the respondents. CONCLUSIONS: Treatment recommendations showed an increasing variation with more advanced disease stages from B1 through B2 to C. This reflects the increasing disagreement among the panelists who prepared the ACVIM consensus guidelines. Practitioners of our study seem to practice more evidence-based medicine than veterinary cardiologists, as it was reported in a recent survey-based study.

6.
Cancer ; 130(1): 150-161, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37688396

RESUMO

BACKGROUND: This study investigated the influence of oral microbial features on the trajectory of oral mucositis (OM) in patients with squamous cell carcinoma of the head and neck. METHODS: OM severity was assessed and buccal swabs were collected at baseline, at the initiation of cancer treatment, weekly during cancer treatment, at the termination of cancer treatment, and after cancer treatment termination. The oral microbiome was characterized via the 16S ribosomal RNA V4 region with the Illumina platform. Latent class mixed-model analysis was used to group individuals with similar trajectories of OM severity. Locally estimated scatterplot smoothing was used to fit an average trend within each group and to assess the association between the longitudinal OM scores and longitudinal microbial abundances. RESULTS: Four latent groups (LGs) with differing patterns of OM severity were identified for 142 subjects. LG1 has an early onset of high OM scores. LGs 2 and 3 begin with relatively low OM scores until the eighth and 11th week, respectively. LG4 has generally flat OM scores. These LGs did not vary by treatment or clinical or demographic variables. Correlation analysis showed that the abundances of Bacteroidota, Proteobacteria, Bacteroidia, Gammaproteobacteria, Enterobacterales, Bacteroidales, Aerococcaceae, Prevotellaceae, Abiotrophia, and Prevotella_7 were positively correlated with OM severity across the four LGs. Negative correlation was observed with OM severity for a few microbial features: Abiotrophia and Aerococcaceae for LGs 2 and 3; Gammaproteobacteria and Proteobacteria for LGs 2, 3, and 4; and Enterobacterales for LGs 2 and 4. CONCLUSIONS: These findings suggest the potential to personalize treatment for OM. PLAIN LANGUAGE SUMMARY: Oral mucositis (OM) is a common and debilitating after effect for patients treated for squamous cell carcinoma of the head and neck. Trends in the abundance of specific microbial features may be associated with patterns of OM severity over time. Our findings suggest the potential to personalize treatment plans for OM via tailored microbiome interventions.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Microbiota , Estomatite , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Carcinoma de Células Escamosas/tratamento farmacológico
7.
J Cutan Pathol ; 51(1): 63-69, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37565512

RESUMO

BACKGROUND: Pigmented purpuric dermatosis (PPD) is characterized by grouped petechiae, purpuric macules, and pigmentation in the bilateral lower extremities. It runs a chronic and relapsing course. Pathophysiology is poorly understood, but it has been proposed to be an immune-complex disease or capillaritis. This study aimed to determine the incidence and patterns of positive direct immunofluorescence (DIF) findings in patients with clinically and histopathologically confirmed PPD. The association between DIF deposition type and clinical profile was also analyzed. METHODS: Patients with a clinical and histopathologic PPD diagnosis who had undergone DIF studies at a tertiary medical center with attached dermatopathology and immunofluorescence diagnostic centers between January 2002 and December 2021 were included in this study. Data on age, sex, disease duration, comorbidities, and drug intake were collected from medical records. RESULTS: There were 65 patients who satisfied the inclusion criteria. Among them, 58 (89%) had at least one positive finding and 53 (82%) were vascular deposition of immunoglobulin (Ig), complement, or fibrinogen. The most common vascular deposition was fibrinogen (71%) followed by C3 (62%), IgM (18%), IgA (6%), and IgG (3%). Fibrinogen deposition was associated with hypertension (p < 0.03). There was no association between vascular DIF deposition of IgG, IgA, and C3, with age, sex, comorbidities, disease duration, and drug history. CONCLUSION: The most common DIF findings in PPD were vascular deposition of fibrinogen and C3, with or without Ig presence. DIF findings supported a vascular origin in PPD but not an immune complex-mediated disease. Hypertension was associated with fibrinogen deposition and may play a role in its pathophysiology.


Assuntos
Hipertensão , Púrpura , Dermatopatias Vasculares , Humanos , Estudos Retrospectivos , Técnica Direta de Fluorescência para Anticorpo , Fibrinogênio/análise , Imunoglobulina A , Imunoglobulina G
8.
Int J Mol Sci ; 24(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38069314

RESUMO

Oral mucositis (OM) is a common and clinically impactful side effect of cytotoxic cancer treatment, particularly in patients with head and neck squamous cell carcinoma (HNSCC) who undergo radiotherapy with or without concomitant chemotherapy. The etiology and pathogenic mechanisms of OM are complex, multifaceted and elicit both direct and indirect damage to the mucosa. In this narrative review, we describe studies that use various omics methodologies (genomics, transcriptomics, microbiomics and metabolomics) in attempts to elucidate the biological pathways associated with the development or severity of OM. Integrating different omics into multi-omics approaches carries the potential to discover links among host factors (genomics), host responses (transcriptomics, metabolomics), and the local environment (microbiomics).


Assuntos
Antineoplásicos , Neoplasias de Cabeça e Pescoço , Mucosite , Estomatite , Humanos , Estomatite/etiologia , Neoplasias de Cabeça e Pescoço/complicações , Carcinoma de Células Escamosas de Cabeça e Pescoço/complicações
9.
Sci Rep ; 13(1): 22855, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129450

RESUMO

Alteration of basaltic glass and in situ mineral growth are fundamental processes that influence the chemical and material properties of Earth's oceanic crust. These processes have evolved at the basaltic island of Surtsey (SW Iceland) since eruptions terminated in 1967. Here, subaerial and submarine lapilli tuff samples from a 192 m-deep borehole drilled in 2017 (SE-02b) are characterized through petrographic studies, X-ray powder diffraction analyses, and SEM-EDS imaging and chemical analyses. The integrated results reveal (i) multi-stage palagonitization processes in basaltic glass and precipitation of secondary minerals from matrix pore fluids, (ii) multi-stage crystallization of secondary phillipsite, analcime and Al-tobermorite in the vesicles of basaltic pyroclasts and (iii) variations in palagonitization processes as a function of thermal and hydrological domains. Although temperature appears to be an important factor in controlling rates of secondary mineralization, the chemistry of original basaltic components and interstitial fluids also influences reaction pathways in the young pyroclastic deposits. The integration of systematic mineralogical analyses of the 50-year-old tuff from one of the most carefully monitored volcanic sites on Earth, together with temperature monitoring in boreholes since 1980, provide a reference framework for evaluating mineralogical evolution in other Surtseyan-type volcanoes worldwide.

10.
Vet Sci ; 10(12)2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38133238

RESUMO

BACKGROUND: ACVIM developed and published guidelines for staging myxomatous mitral valve degeneration in dogs in 2009. An updated version was published in 2019. The present study aimed to investigate whether these guidelines are actually used by the intended public more than a decade after their first publication. METHODS: An online survey was distributed among Dutch and Belgian veterinarians through online channels and mailing lists. RESULTS: Of the 524 responses, only 363 complete surveys were analyzed. The ACVIM guidelines are used by 60% of the respondents. Veterinarians find it more difficult to differentiate stage B1 from B2 in asymptomatic dogs compared to diagnosing stage C. Three-quarters of the respondents would recommend echocardiography for an incidentally detected new murmur with an intensity of 3 out of 6 in an adult dog. Two-thirds of the respondents find coughing a convincing finding for stage C disease. Close to half of the respondents associate a horizontal, dull percussion line with pulmonary edema. For confirming cardiogenic pulmonary edema, 98% of the respondents used thoracic radiographs. CONCLUSIONS: Veterinary practitioners might not have the expected training and equipment to be able to apply the guidelines in their practices, especially in the differentiation of stage B1 from stage B2.

11.
ACS Omega ; 8(39): 35791-35799, 2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37810720

RESUMO

The mutable collagenous tissue (MCT) of sea cucumber, with its ability to rapidly change its stiffness and extensibility in response to different environmental stress conditions, serves as inspiration for the design of new smart functional biomaterials. Collagen, extracted from the body wall of Stichopus cf. horrens, a species commonly found in the Philippines, was characterized for its suitability as stimuli-responsive films. Protein BLAST search showed the presence of sequences commonly found in type VII and IX collagen, suggesting that Stichopus horrens collagen is heterotypic. The maximum transition temperature recorded was 56.0 ± 2 °C, which is higher than those of other known sources of marine collagen. This suggests that S. horrens collagen has better thermal stability and durability. Collagen-based thin films were then prepared, and atomic force microscopy (AFM) imaging showed the visible collagen network comprising the films. The thin films were subjected to thermomechanical analysis with degradation starting at >175 °C. At 100-150 °C, the collagen-based films apparently lose their translucency due to the removal of moisture. Upon exposure to ambient temperature, instead of degrading, the films were able to revert to the original state due to the readsorption of moisture. This study is a demonstration of a smart biomaterial developed from S. cf. horrens collagen with potential applications in food, pharmaceutical, biomedical, and other collagen-based research.

12.
Dent Clin North Am ; 67(4): 707-709, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37714630

RESUMO

In this case a woman with gestational diabetes and otherwise healthy pregnancy needs scaling and root planning for the treatment of stage I periodontal disease during pregnancy. Her daily blood sugars are in the target range, and there are no contraindications to providing necessary dental treatment under local anesthesia with vasoconstrictors in her case.


Assuntos
Diabetes Gestacional , Doenças Periodontais , Feminino , Gravidez , Humanos , Diabetes Gestacional/terapia , Nível de Saúde
13.
Dent Clin North Am ; 67(4): 605-607, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37714605

RESUMO

An older adult with diabetes is taking glipizide, a sulfonylurea class drug. Subsequently, she experiences a hypoglycemic episode in the dental office. Prompt recognition of hypoglycemia and administration of glucose or sugar is vital. Patient and provider education about the risks of hypoglycemia in older adults may help to prevent future hypoglycemic episodes.


Assuntos
Hipoglicemia , Hipoglicemiantes , Feminino , Humanos , Idoso , Hipoglicemiantes/efeitos adversos , Hipoglicemia/induzido quimicamente , Compostos de Sulfonilureia/efeitos adversos , Glipizida
14.
Dent Clin North Am ; 67(4): 609-611, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37714606

RESUMO

In this case a patient has multiple risk factors for diabetes including periodontal disease, family history positive for diabetes, and body mass index of 24 in an Asian American. He has no medical or dental home and upon presenting to the dental office would be a good candidate for diabetes screening.


Assuntos
Diabetes Mellitus Tipo 2 , Doenças Periodontais , Idoso , Masculino , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Fatores de Risco
15.
Dent Clin North Am ; 67(4): 613-615, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37714607

RESUMO

A patient with type II diabetes and renal disease developed infection and bleeding after periodontal osseous surgery. The clinician did not adequately assess the patient's long-term glycemic status or stage of chronic kidney disease (CKD) before initiating osseous surgery. Preoperative assessment of patients with diabetes should include at a minimum an Hba1c within 3 months and estimated glomerular filtration rate for CKD.


Assuntos
Diabetes Mellitus Tipo 2 , Procedimentos Cirúrgicos Bucais , Insuficiência Renal Crônica , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/cirurgia
16.
Dent Clin North Am ; 67(4): 617-619, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37714608

RESUMO

A patient with type I diabetes withheld her diabetes medications without consulting her physician and was not able to resume her normal diet after extensive dental surgery resulting in hyperglycemia postoperatively. Clear communication between clinicians and patient about the expected postoperative course and changes to factors that may influence glycemic control could prevent hyperglycemia in the postoperative period.


Assuntos
Diabetes Mellitus , Hiperglicemia , Feminino , Humanos , Hiperglicemia/etiologia , Comunicação , Período Pós-Operatório , Encaminhamento e Consulta
17.
Animals (Basel) ; 13(15)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37570236

RESUMO

BACKGROUND: A high perinatal mortality rate in the Stabyhoun breed prompted one of the Dutch breeding organizations to start an investigation. Preductal segmental tubular aortic hypoplasia is an extremely rarely documented congenital vascular anomaly in dogs, and it is suspected to be the result of constriction of ectopic ductal tissue in the aortic wall at birth. METHODS: Over a period of 18 months, Stabyhoun puppies that were stillborn, died or were euthanized before 3 weeks of age were submitted to post-mortem examination at the reporting institution. Pathologic findings were documented. RESULTS: Eight Stabyhoun puppies were submitted during the study period. In five of them, a severe preductal segmental tubular aortic hypoplasia was found. Two of the five puppies were stillborn, and three died spontaneously or were euthanized. CONCLUSIONS: Preductal tubular aortic hypoplasia was found in an unusually high frequency in the examined Stabyhoun puppies. Because the condition is believed to cause clinical signs only after birth, this anomaly cannot explain the death of the stillborn puppies. However, it might be responsible for cardiogenic pulmonary edema in the postnatal period. Routine dissection of the great vessels in perinatally deceased puppies would help to establish the prevalence of congenital anomalies of the aorta.

18.
Adv Healthc Mater ; 12(26): e2300960, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37395729

RESUMO

Bioresorbable perivascular scaffolds loaded with antiproliferative agents have been shown to enhance arteriovenous fistula (AVF) maturation by inhibiting neointimal hyperplasia (NIH). These scaffolds, which can mimic the three-dimensional architecture of the vascular extracellular matrix, also have an untapped potential for the local delivery of cell therapies against NIH. Hence, an electrospun perivascular scaffold from polycaprolactone (PCL) to support mesenchymal stem cell (MSC) attachment and gradual elution at the AVF's outflow vein is fabricated. Chronic kidney disease (CKD) in Sprague-Dawley rats is induced by performing 5/6th nephrectomy, then AVFs for scaffold application are created. The following groups of CKD rats are compared: no perivascular scaffold (i.e., control), PCL alone, and PCL+MSC scaffold. PCL and PCL+MSC significantly improve ultrasonographic (i.e., luminal diameter, wall-to-lumen ratio, and flow rate) and histologic (i.e., neointima-to-lumen ratio, neointima-to-media ratio) parameters compared to control, with PCL+MSC demonstrating further improvement in these parameters compared to PCL alone. Moreover, only PCL+MSC significantly reduces 18 F-fluorodeoxyglucose uptake on positron emission tomography. These findings suggest that adding MSCs promotes greater luminal expansion and potentially reduces the inflammatory process underlying NIH. The results demonstrate the utility of mechanical support loaded with MSCs at the outflow vein immediately after AVF formation to support maturation by minimizing NIH.


Assuntos
Fístula Arteriovenosa , Derivação Arteriovenosa Cirúrgica , Células-Tronco Mesenquimais , Insuficiência Renal Crônica , Ratos , Animais , Hiperplasia/patologia , Ratos Sprague-Dawley , Neointima/patologia , Implantes Absorvíveis , Tomografia Computadorizada por Raios X , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/patologia , Fístula Arteriovenosa/patologia , Células-Tronco Mesenquimais/patologia , Alicerces Teciduais
19.
Int J Mol Sci ; 24(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37511512

RESUMO

Mesenchymal stem cell (MSC)-seeded polymeric perivascular wraps have been shown to enhance arteriovenous fistula (AVF) maturation. However, the wraps' radiolucency makes their placement and integrity difficult to monitor. Through electrospinning, we infused gold nanoparticles (AuNPs) into polycaprolactone (PCL) wraps to improve their radiopacity and tested whether infusion affects the previously reported beneficial effects of the wraps on the AVF's outflow vein. Sprague Dawley rat MSCs were seeded on the surface of the wraps. We then compared the effects of five AVF treatments-no perivascular wrap (i.e., control), PCL wrap, PCL + MSC wrap, PCL-Au wrap, and PCL-Au + MSC wrap-on AVF maturation in a Sprague Dawley rat model of chronic kidney disease (n = 3 per group). Via micro-CT, AuNP-infused wraps demonstrated a significantly higher radiopacity compared to that of the wraps without AuNPs. Wraps with and without AuNPs equally reduced vascular stenoses, as seen via ultrasonography and histomorphometry. In the immunofluorescence analysis, representative MSC-seeded wraps demonstrated reduced neointimal staining for markers of infiltration with smooth muscle cells (α-SMA), inflammatory cells (CD45), and fibroblasts (vimentin) compared to that of the control and wraps without MSCs. In conclusion, AuNP infusion allows in vivo monitoring via micro-CT of MSC-seeded polymeric wraps over time, without compromising the benefits of the wrap for AVF maturation.


Assuntos
Fístula Arteriovenosa , Células-Tronco Mesenquimais , Nanopartículas Metálicas , Ratos , Animais , Ouro , Ratos Sprague-Dawley , Implantes Absorvíveis , Fístula Arteriovenosa/terapia
20.
Biomed Eng Online ; 22(1): 63, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355651

RESUMO

BACKGROUND: The underlying motivation of this work is to demonstrate that artificial muscle activity of known and unknown motion can be generated based on motion parameters, such as angular position, acceleration, and velocity of each joint (or the end-effector instead), which are similarly represented in our brains. This model is motivated by the known motion planning process in the central nervous system. That process incorporates the current body state from sensory systems and previous experiences, which might be represented as pre-learned inverse dynamics that generate associated muscle activity. METHODS: We develop a novel approach utilizing recurrent neural networks that are able to predict muscle activity of the upper limbs associated with complex 3D human arm motions. Therefore, motion parameters such as joint angle, velocity, acceleration, hand position, and orientation, serve as input for the models. In addition, these models are trained on multiple subjects (n=5 including , 3 male in the age of 26±2 years) and thus can generalize across individuals. In particular, we distinguish between a general model that has been trained on several subjects, a subject-specific model, and a specific fine-tuned model using a transfer learning approach to adapt the model to a new subject. Estimators such as mean square error MSE, correlation coefficient r, and coefficient of determination R2 are used to evaluate the goodness of fit. We additionally assess performance by developing a new score called the zero-line score. The present approach was compared with multiple other architectures. RESULTS: The presented approach predicts the muscle activity for previously through different subjects with remarkable high precision and generalizing nicely for new motions that have not been trained before. In an exhausting comparison, our recurrent network outperformed all other architectures. In addition, the high inter-subject variation of the recorded muscle activity was successfully handled using a transfer learning approach, resulting in a good fit for the muscle activity for a new subject. CONCLUSIONS: The ability of this approach to efficiently predict muscle activity contributes to the fundamental understanding of motion control. Furthermore, this approach has great potential for use in rehabilitation contexts, both as a therapeutic approach and as an assistive device. The predicted muscle activity can be utilized to guide functional electrical stimulation, allowing specific muscles to be targeted and potentially improving overall rehabilitation outcomes.


Assuntos
Redes Neurais de Computação , Extremidade Superior , Humanos , Masculino , Adulto Jovem , Adulto , Fenômenos Biomecânicos , Movimento/fisiologia , Músculos , Eletromiografia/métodos
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