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1.
Heliyon ; 10(11): e31590, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38841503

RESUMO

The tourism sector is presently facing new challenges resulting from the increasing digitalization of society. Boosted by industry 4.0, new tourism dynamics are emerging. Nonetheless, the real significance of this revolutionary trend and its implications still lack further development. Aiming to assess the state-of-the-art about the digital transformation on the tourism sector, triggered by the 4.0 paradigm, the present study followed a systematic literature review approach, adopting the PRISMA protocol guidelines. A total of 44 manuscripts were considered relevant for analysis. The findings illustrate that the 4.0 paradigm is being embraced from three main perspectives: the visitor-technology interaction and its influence on decision-making, the digital competencies in tourism students, and the technology penetration in different sub-sectors of the supply chain. However, studies conceptualizing the 4.0 paradigm in the tourism sector are lacking, beyond empirical research on areas such as digital skills, pros and cons of industry 4.0 technologies, and spatial consequences.

2.
Nucleic Acids Res ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783112

RESUMO

Protein-protein interactions (PPIs) play a vital role in cellular functions and are essential for therapeutic development and understanding diseases. However, current predictive tools often struggle to balance efficiency and precision in predicting the effects of mutations on these complex interactions. To address this, we present DDMut-PPI, a deep learning model that efficiently and accurately predicts changes in PPI binding free energy upon single and multiple point mutations. Building on the robust Siamese network architecture with graph-based signatures from our prior work, DDMut, the DDMut-PPI model was enhanced with a graph convolutional network operated on the protein interaction interface. We used residue-specific embeddings from ProtT5 protein language model as node features, and a variety of molecular interactions as edge features. By integrating evolutionary context with spatial information, this framework enables DDMut-PPI to achieve a robust Pearson correlation of up to 0.75 (root mean squared error: 1.33 kcal/mol) in our evaluations, outperforming most existing methods. Importantly, the model demonstrated consistent performance across mutations that increase or decrease binding affinity. DDMut-PPI offers a significant advancement in the field and will serve as a valuable tool for researchers probing the complexities of protein interactions. DDMut-PPI is freely available as a web server and an application programming interface at https://biosig.lab.uq.edu.au/ddmut_ppi.

3.
Sci Rep ; 14(1): 11575, 2024 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773273

RESUMO

Leishmaniasis is a disease caused by a protozoan of the genus Leishmania, affecting millions of people, mainly in tropical countries, due to poor social conditions and low economic development. First-line chemotherapeutic agents involve highly toxic pentavalent antimonials, while treatment failure is mainly due to the emergence of drug-resistant strains. Leishmania arginase (ARG) enzyme is vital in pathogenicity and contributes to a higher infection rate, thus representing a potential drug target. This study helps in designing ARG inhibitors for the treatment of leishmaniasis. Py-CoMFA (3D-QSAR) models were constructed using 34 inhibitors from different chemical classes against ARG from L. (L.) amazonensis (LaARG). The 3D-QSAR predictions showed an excellent correlation between experimental and calculated pIC50 values. The molecular docking study identified the favorable hydrophobicity contribution of phenyl and cyclohexyl groups as substituents in the enzyme allosteric site. Molecular dynamics simulations of selected protein-ligand complexes were conducted to understand derivatives' interaction modes and affinity in both active and allosteric sites. Two cinnamide compounds, 7g and 7k, were identified, with similar structures to the reference 4h allosteric site inhibitor. These compounds can guide the development of more effective arginase inhibitors as potential antileishmanial drugs.


Assuntos
Arginase , Inibidores Enzimáticos , Leishmania , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Arginase/antagonistas & inibidores , Arginase/química , Arginase/metabolismo , Leishmania/enzimologia , Leishmania/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Relação Quantitativa Estrutura-Atividade , Proteínas de Protozoários/antagonistas & inibidores , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Sítio Alostérico , Antiprotozoários/farmacologia , Antiprotozoários/química , Domínio Catalítico
4.
Pharmaceutics ; 16(5)2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38794280

RESUMO

Silybin (SIB) is a hepatoprotective drug known for its poor oral bioavailability, attributed to its classification as a class IV drug with significant metabolism during the first-pass effect. This study explored the potential of solid lipid nanoparticles with (SLN-SIB-U) or without (SLN-SIB) ursodeoxycholic acid and polymeric nanoparticles (PN-SIB) as delivery systems for SIB. The efficacy of these nanosystems was assessed through in vitro studies using the GRX and Caco-2 cell lines for permeability and proliferation assays, respectively, as well as in vivo experiments employing a murine model of Schistosomiasis mansoni infection in BALB/c mice. The mean diameter and encapsulation efficiency of the nanosystems were as follows: SLN-SIB (252.8 ± 4.4 nm, 90.28 ± 2.2%), SLN-SIB-U (252.9 ± 14.4 nm, 77.05 ± 2.8%), and PN-SIB (241.8 ± 4.1 nm, 98.0 ± 0.2%). In the proliferation assay with the GRX cell line, SLN-SIB and SLN-SIB-U exhibited inhibitory effects of 43.09 ± 5.74% and 38.78 ± 3.78%, respectively, compared to PN-SIB, which showed no inhibitory effect. Moreover, SLN-SIB-U demonstrated a greater apparent permeability coefficient (25.82 ± 2.2) than PN-SIB (20.76 ± 0.1), which was twice as high as that of SLN-SIB (11.32 ± 4.6) and pure SIB (11.28 ± 0.2). These findings suggest that solid lipid nanosystems hold promise for further in vivo investigations. In the murine model of acute-phase Schistosomiasis mansoni infection, both SLN-SIB and SLN-SIB-U displayed hepatoprotective effects, as evidenced by lower alanine amino transferase values (22.89 ± 1.6 and 23.93 ± 2.4 U/L, respectively) than those in control groups I (29.55 ± 0.7 U/L) and I+SIB (34.29 ± 0.3 U/L). Among the prepared nanosystems, SLN-SIB-U emerges as a promising candidate for enhancing the pharmacokinetic properties of SIB.

5.
Sci Rep ; 14(1): 8991, 2024 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637583

RESUMO

COVID-19 is a multisystemic disease caused by the SARS-CoV-2 airborne virus, a member of the Coronaviridae family. It has a positive sense single-stranded RNA genome and encodes two non-structural proteins through viral cysteine-proteases processing. Blocking this step is crucial to control virus replication. In this work, we reported the synthesis of 23 statine-based peptidomimetics to determine their ability to inhibit the main protease (Mpro) activity of SARS-CoV-2. Among the 23 peptidomimetics, 15 compounds effectively inhibited Mpro activity by 50% or more, while three compounds (7d, 8e, and 9g) exhibited maximum inhibition above 70% and IC50 < 1 µM. Compounds 7d, 8e, and 9g inhibited roughly 80% of SARS-CoV-2 replication and proved no cytotoxicity. Molecular docking simulations show putative hydrogen bond and hydrophobic interactions between specific amino acids and these inhibitors. Molecular dynamics simulations further confirmed the stability and persisting interactions in Mpro's subsites, exhibiting favorable free energy binding (ΔGbind) values. These findings suggest the statine-based peptidomimetics as potential therapeutic agents against SARS-CoV-2 by targeting Mpro.


Assuntos
COVID-19 , Proteases 3C de Coronavírus , Peptidomiméticos , Humanos , SARS-CoV-2/metabolismo , Peptidomiméticos/farmacologia , Simulação de Acoplamento Molecular , Inibidores de Proteases/química , Aminoácidos , Simulação de Dinâmica Molecular , Antivirais/farmacologia , Antivirais/química
6.
Bioorg Med Chem ; 102: 117671, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38452407

RESUMO

The search for novel anticancer drugs is essential to expand treatment options, overcome drug resistance, reduce toxicity, promote innovation, and tackle the economic impact. The importance of these studies lies in their contribution to advancing cancer research and enhancing patient outcomes in the battle against cancer. Here, we developed new asymmetric hybrids containing two different naphthoquinones linked by a 1,2,3-1H-triazole nucleus, which are potential new drugs for cancer treatment. The antitumor activity of the novel compounds was tested using the breast cancer cell lines MCF-7 and MDA-MB-231, using the non-cancer cell line MCF10A as control. Our results showed that two out of twenty-two substances tested presented potential antitumor activity against the breast cancer cell lines. These potential drugs, named here 12g and 12h were effective in reducing cell viability and promoting cell death of the tumor cell lines, exhibiting minimal effects on the control cell line. The mechanism of action of the novel drugs was assessed revealing that both drugs increased reactive oxygen species production with consequent activation of the AMPK pathway. Therefore, we concluded that 12g and 12h are novel AMPK activators presenting selective antitumor effects.


Assuntos
Antineoplásicos , Neoplasias da Mama , Naftoquinonas , Humanos , Feminino , Células MCF-7 , Espécies Reativas de Oxigênio/metabolismo , Triazóis/farmacologia , Naftoquinonas/farmacologia , Proteínas Quinases Ativadas por AMP , Proliferação de Células , Apoptose , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Ensaios de Seleção de Medicamentos Antitumorais
7.
Curr Med Chem ; 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38310396

RESUMO

INTRODUCTION: Thrombotic disorders are among the leading causes of morbidity and mortality worldwide. Drugs used in the prevention and treatment of atherothrombosis have pharmacokinetic limitations and adverse effects such as hemorrhagic conditions, highlighting the importance of developing more effective antiplatelet agents. ethod: In this work, we synthesized N,N'-disubstituted ureas 3a-3j and evaluated their antiplatelet profiles through in vitro, ex vivo, and in silico studies. The synthesized derivatives exhibited a selective inhibitory profile against platelet aggregation induced by arachidonic acid (AA) in vitro, without significantly affecting other aspects of primary hemostasis and blood coagulation. The compounds that showed inhibition greater than 85% were submitted to the analysis of their potency by calculating the concentration required to inhibit 50% of platelet aggregation induced by AA (IC50). Urea derivative 3a was the most potent with IC50 of 1.45 µM. Interestingly, this derivative inhibited more than 90% of platelet aggregation induced by AA ex vivo, with a similar effect to acetylsalicylic acid. In the hemolysis assay, most of the urea derivatives presented values below 10% suggesting good hemocompatibility. Additionally, the compounds tested at 100 µM also showed no cytotoxic effects in HepG2 and Vero cells. RESULT: The in silico results suggested that compound 3a may bind to the key residue of COX-1 similar to AA and known COX-1 inhibitors, and the results are also in agreement with our SAR, which suggests that the inhibition of this enzyme is the most likely mechanism of antiplatelet activity. CONCLUSION: Therefore, these results demonstrated that N,N'-disubstituted ureas are promising candidates for the development of novel antiplatelet agents.

8.
Sci Rep ; 14(1): 3110, 2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326387

RESUMO

The main objective of the present work was to highlight differences and similarities in gene expression patterns between different pluripotent stem cell cardiac differentiation protocols, using a workflow based on unsupervised machine learning algorithms to analyse the transcriptome of cells cultured as a 2D monolayer or as 3D aggregates. This unsupervised approach effectively allowed to portray the transcriptomic changes that occurred throughout the differentiation processes, with a visual representation of the entire transcriptome. The results allowed to corroborate previously reported data and also to unveil new gene expression patterns. In particular, it was possible to identify a correlation between low cardiomyocyte differentiation efficiencies and the early expression of a set of non-mesodermal genes, which can be further explored as predictive markers of differentiation efficiency. The workflow here developed can also be applied to analyse other stem cell differentiation transcriptomic datasets, envisaging future clinical implementation of cellular therapies.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Humanos , Transcriptoma , Diferenciação Celular/genética , Células-Tronco Pluripotentes/metabolismo , Perfilação da Expressão Gênica/métodos , Miócitos Cardíacos/metabolismo
9.
Hum Genet ; 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227011

RESUMO

Missense mutations are known contributors to diverse genetic disorders, due to their subtle, single amino acid changes imparted on the resultant protein. Because of this, understanding the impact of these mutations on protein stability and function is crucial for unravelling disease mechanisms and developing targeted therapies. The Critical Assessment of Genome Interpretation (CAGI) provides a valuable platform for benchmarking state-of-the-art computational methods in predicting the impact of disease-related mutations on protein thermodynamics. Here we report the performance of our comprehensive platform of structure-based computational approaches to evaluate mutations impacting protein structure and function on 3 challenges from CAGI6: Calmodulin, MAPK1 and MAPK3. Our stability predictors have achieved correlations of up to 0.74 and AUCs of 1 when predicting changes in ΔΔG for MAPK1 and MAPK3, respectively, and AUC of up to 0.75 in the Calmodulin challenge. Overall, our study highlights the importance of structure-based approaches in understanding the effects of missense mutations on protein thermodynamics. The results obtained from the CAGI6 challenges contribute to the ongoing efforts to enhance our understanding of disease mechanisms and facilitate the development of personalised medicine approaches.

10.
Cien Saude Colet ; 28(11): 3383-3394, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37971018

RESUMO

The aim is to present validity evidence of the Brazilian-Portuguese Recovery Experience Questionnaire (REQ-PB) by applying a procedure to decentering cross-cultural scales translation and adaptation. First, we had a phase with bilingual experts, which assessed different criteria of translation quality. In sequence, we conducted the replication of the original research to achieve validity indicators in the Brazilian context. We carried out both Confirmatory Factor Analysis (to find structural validity indicators) and correlations with various external variables (to find convergent validity indicators). Step 1 showed promising results of decentering translation. In step 2 participated 164 workers and the CFA confirmed the four-factor model: psychological detachment from work, relaxation, mastery experience, and control over leisure time. The convergent validity showed a significant correlation with external variables. The REQ-PB showed adequate psychometric properties and may explain and compare empirical evidence of the recovery topic. We concluded that we have a good quality scale to be used in future research and integrated with other constructs to support interventions.


Assuntos
Etnicidade , Atividades de Lazer , Humanos , Brasil , Portugal , Inquéritos e Questionários , Psicometria , Reprodutibilidade dos Testes , Comparação Transcultural
11.
Curr Pharm Des ; 29(38): 3040-3049, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37957861

RESUMO

BACKGROUND: Oral suspensions are heterogeneous disperse systems, and the particle size distribution, crystalline form of the dispersed solid, and composition of the formulation can be listed as parameters that control the drug dissolution rate and its bioavailability. OBJECTIVE: The aim of this work was to develop a discriminative dissolution test, which, in association with in silico methodologies, can make it possible to safely anticipate bioavailability problems. METHODS: Nimesulide and ibuprofen (BCS class II) and cephalexin (BCS class I) oral suspensions were studied. Previously, solid-state structure and particle size in active pharmaceutical ingredients were characterized and the impact of differences on solubility was evaluated for the choice of discriminative medium. Afterwards, particle size distribution (0.1 to 360 µm), dissolution profile, and in vitro permeability in Caco-2 cell of commercial suspensions, were determined. These parameters were used as input for the establishment of the in vitro-in vivo correlation (IVIVC) for the suspensions using the GastroPlus™ with Wagner-Nelson and Loo- Riegelmann deconvolution approach. RESULTS: The predicted/observed pharmacokinetic model showed good correlation coefficients (r) of 0.960, 0.950, and 0.901, respectively. The IVIVC was established for one nimesulide and two ibuprofen suspensions with r between 0.956 and 0.932, and the percent prediction error (%PE) did not exceed 15%. CONCLUSION: In this work, we have performed a complete study combining in vitro/in silico approaches with the aim of anticipating the safety and efficacy of oral pharmaceutical suspensions in order to provide a regulatory tool for this category of products in a faster and more economical way.


Assuntos
Ibuprofeno , Sulfonamidas , Humanos , Disponibilidade Biológica , Ibuprofeno/química , Ibuprofeno/farmacocinética , Células CACO-2 , Solubilidade , Suspensões
12.
Rev Bras Enferm ; 76(5): e20220457, 2023.
Artigo em Inglês, Português | MEDLINE | ID: mdl-38018611

RESUMO

OBJECTIVES: to improve an instrument that measures postpartum women's satisfaction with obstetric care. METHODS: action research, developed from a preliminary version of an instrument prepared by nurse-midwives working in public services in the Federal District. The analysis of the results of application of instrument carried out in a pilot test, analysis of evidence of instrument validity, literature review, focus group with the instrument's developers and interview with the target audience were carried out. RESULTS: factorial analysis showed three existing factors in the construct. Seven nurses participated, discussing the instrument reformulation, and 20 mothers reported their perceptions about the care received during childbirth, generating five thematic units. FINAL CONSIDERATIONS: instrument improvement occurred through item and response scale reconstruction and reorganization, in addition to application of a pre-test with the target population, resulting in an instrument composed of 13 items.


Assuntos
Satisfação do Paciente , Período Pós-Parto , Gravidez , Feminino , Humanos , Parto , Mães , Parto Obstétrico , Reprodutibilidade dos Testes , Inquéritos e Questionários
13.
Ciênc. Saúde Colet. (Impr.) ; 28(11): 3383-3394, nov. 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1520643

RESUMO

Abstract The aim is to present validity evidence of the Brazilian-Portuguese Recovery Experience Questionnaire (REQ-PB) by applying a procedure to decentering cross-cultural scales translation and adaptation. First, we had a phase with bilingual experts, which assessed different criteria of translation quality. In sequence, we conducted the replication of the original research to achieve validity indicators in the Brazilian context. We carried out both Confirmatory Factor Analysis (to find structural validity indicators) and correlations with various external variables (to find convergent validity indicators). Step 1 showed promising results of decentering translation. In step 2 participated 164 workers and the CFA confirmed the four-factor model: psychological detachment from work, relaxation, mastery experience, and control over leisure time. The convergent validity showed a significant correlation with external variables. The REQ-PB showed adequate psychometric properties and may explain and compare empirical evidence of the recovery topic. We concluded that we have a good quality scale to be used in future research and integrated with other constructs to support interventions.


Resumo O objetivo é apresentar evidências da validade do Questionário de Experiência de Restauro em português brasileiro (REQ-PB) por meio da aplicação de um procedimento de descentralização para tradução e adaptação de escalas transculturais. Inicialmente, tivemos uma fase com especialistas bilíngues que avaliaram a qualidade da tradução utilizando diferentes critérios. Na sequência, realizamos a replicação da pesquisa original para alcançar os indicadores de validade no contexto brasileiro. Efetuamos tanto a análise fatorial confirmatória (para encontrar indicadores de validade estrutural) quanto correlações com variáveis externas (para encontrar indicadores de validade convergentes). O passo 1 mostrou resultados promissores na tradução descentralizada. No passo 2, participaram 164 trabalhadores e a análise fatorial confirmatória confirmou o modelo de quatro fatores: distanciamento psicológico do trabalho, relaxamento, experiência de domínio e controle do tempo livre. A validade convergente mostrou uma correlação significativa com variáveis externas. O REQ-PB mostrou propriedades psicométricas adequadas capazes de explicar e comparar evidências empíricas do tópico de restauro. Em resumo, a escala pode ser utilizada em pesquisas futuras e integrada aoutros construtos para orientar intervenções.

14.
Front Oncol ; 13: 1202200, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37860190

RESUMO

Introduction: Cranial irradiation (IR) negatively regulates hippocampal neurogenesis and causes cognitive dysfunctions in cancer survivors, especially in pediatric patients. IR decreases proliferation of neural stem/progenitor cells (NSPC) and consequently diminishes production of new hippocampal neurons. Memantine, an NMDA receptor antagonist, used clinically to improve cognition in patients suffering from Alzheimer's disease and dementia. In animal models, memantine acts as a potent enhancer of hippocampal neurogenesis. Memantine was recently proposed as an intervention to improve cognitive impairments occurring after radiotherapy and is currently under investigation in a number of clinical trials, including pediatric patients. To date, preclinical studies investigating the mechanisms underpinning how memantine improves cognition after IR remain limited, especially in the young, developing brain. Here, we investigated whether memantine could restore proliferation in the subgranular zone (SGZ) or rescue the reduction in the number of hippocampal young neurons after IR in the juvenile mouse brain. Methods: Mice were whole-brain irradiated with 6 Gy on postnatal day 20 (P20) and subjected to acute or long-term treatment with memantine. Proliferation in the SGZ and the number of young neurons were further evaluated after the treatment. We also measured the levels of neurotrophins associated with memantine improved neural plasticity, brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). Results: We show that acute intraperitoneal treatment with a high, non-clinically used, dose of memantine (50 mg/kg) increased the number of proliferating cells in the intact brain by 72% and prevented 23% of IR-induced decrease in proliferation. Long-term treatment with 10 mg/kg/day of memantine, equivalent to the clinically used dose, did not impact proliferation, neither in the intact brain, nor after IR, but significantly increased the number of young neurons (doublecortin expressing cells) with radial dendrites (29% in sham controls and 156% after IR) and enhanced their dendritic arborization. Finally, we found that long-term treatment with 10 mg/kg/day memantine did not affect the levels of BDNF, but significantly reduced the levels of NGF by 40%. Conclusion: These data suggest that the enhanced dendritic complexity of the hippocampal young neurons after treatment with memantine may contribute to the observed improved cognition in patients treated with cranial radiotherapy.

15.
Proteins ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37870486

RESUMO

Proteins are molecular machinery that participate in virtually all essential biological functions within the cell, which are tightly related to their 3D structure. The importance of understanding protein structure-function relationship is highlighted by the exponential growth of experimental structures, which has been greatly expanded by recent breakthroughs in protein structure prediction, most notably RosettaFold, and AlphaFold2. These advances have prompted the development of several computational approaches that leverage these data sources to explore potential biological interactions. However, most methods are generally limited to analysis of single types of interactions, such as protein-protein or protein-ligand interactions, and their complexity limits the usability to expert users. Here we report CSM-Potential2, a deep learning platform for the analysis of binding interfaces on protein structures. In addition to prediction of protein-protein interactions binding sites and classification of biological ligands, our new platform incorporates prediction of interactions with nucleic acids at the residue level and allows for ligand transplantation based on sequence and structure similarity to experimentally determined structures. We anticipate our platform to be a valuable resource that provides easy access to a range of state-of-the-art methods to expert and non-expert users for the study of biological interactions. Our tool is freely available as an easy-to-use web server and API available at https://biosig.lab.uq.edu.au/csm_potential.

16.
Tissue Eng Part C Methods ; 29(12): 583-595, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37842845

RESUMO

Fecal incontinence, although not life-threatening, has a high impact on the economy and patient quality of life. So far, available treatments are based on both surgical and nonsurgical approaches. These can range from changes in diet, to bowel training, or sacral nerve stimulation, but none of which provides a long-term solution. New regenerative medicine-based therapies are emerging, which aim at regenerating the sphincter muscle and restoring continence. Usually, these consist of the administration of a suspension of expanded skeletal-derived muscle cells (SkMDCs) to the damaged site. However, this strategy often results in a reduced cell viability due to the need for cell harvesting from the expansion platform, as well as the non-native use of a cell suspension to deliver the anchorage-dependent cells. In this study, we propose the proof-of-concept for the bioprocessing of a new cell delivery method for the treatment of fecal incontinence, obtained by a scalable two-step process. First, patient-isolated SkMDCs were expanded using planar static culture systems. Second, by using a single-use PBS-MINI Vertical-Wheel® bioreactor, the expanded SkMDCs were combined with biocompatible and biodegradable (i.e., directly implantable) poly(lactic-co-glycolic acid) microcarriers prepared by thermally induced phase separation. This process allowed for up to 80% efficiency of SkMDCs to attach to the microcarriers. Importantly, SkMDCs were viable during all the process and maintained their myogenic features (e.g., expression of the CD56 marker) after adhesion and culture on the microcarriers. When SkMDC-containing microcarriers were placed on a culture dish, cells were able to migrate from the microcarriers onto the culture surface and differentiate into multinucleated myotubes, which highlights their potential to regenerate the damaged sphincter muscle after administration into the patient. Overall, this study proposes an innovative method to attach SkMDCs to biodegradable microcarriers, which can provide a new treatment for fecal incontinence.


Assuntos
Técnicas de Cultura de Células , Incontinência Fecal , Humanos , Técnicas de Cultura de Células/métodos , Qualidade de Vida , Reatores Biológicos , Músculos
17.
J Vet Intern Med ; 37(6): 2429-2442, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37670479

RESUMO

BACKGROUND: Cytosine arabinoside (Ara-C) is a nucleoside analog prodrug utilized for immunomodulatory effects mediated by its active metabolite Ara-CTP. Optimal dosing protocols for immunomodulation in dogs have not been defined. Cytarabine ocfosfate (CO) is a lipophilic prodrug of Ara-C that can be administered PO and provides prolonged serum concentrations of Ara-C. OBJECTIVES: Provide pharmacokinetic data for orally administered CO and determine accumulation and functional consequences of Ara-CTP within peripheral blood leukocytes. ANIMALS: Three healthy female hound dogs and 1 healthy male Beagle. METHODS: Prospective study. Dogs received 200 mg/m2 of CO PO q24h for 7 doses. Serum and cerebrospinal fluid (CSF) CO and Ara-C concentrations were measured by liquid chromatography-tandem mass spectroscopy (LC-MS/MS). Complete blood counts, flow cytometry, and leukocyte activation assays were done up to 21 days. Incorporation of Ara-CTP within leukocyte DNA was determined by LC-MS/MS. RESULTS: Maximum serum concentration (Cmax ) for Ara-C was 456.1-724.0 ng/mL (1.88-2.98 µM) and terminal half-life was 23.3 to 29.4 hours. Cerebrospinal fluid: serum Ara-C ratios ranged from 0.54 to 1.2. Peripheral blood lymphocyte concentrations remained within the reference range, but proliferation rates poststimulation were decreased at 6 days. Incorporation of Ara-CTP was not saturated and remained >25% of peak concentration at 13 days. CONCLUSIONS AND CLINICAL IMPORTANCE: Oral CO may produce prolonged serum Ara-C half-lives at concentrations sufficient to induce functional changes in peripheral leukocytes and is associated with prolonged retention of DNA-incorporated Ara-CTP. Application of functional and active metabolite assessment is feasible and may provide more relevant data to determine optimal dosing regimens for Ara-C-based treatments.


Assuntos
Arabinofuranosilcitosina Trifosfato , Pró-Fármacos , Feminino , Masculino , Cães , Animais , Cromatografia Líquida/veterinária , Estudos Prospectivos , Espectrometria de Massas em Tandem/veterinária , Leucócitos , Biomarcadores , Citarabina , DNA
18.
Knee Surg Sports Traumatol Arthrosc ; 31(11): 5087-5095, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37728760

RESUMO

PURPOSE: To investigate the combinations of variables that comprise the biopsychosocial model domains to identify clinical profiles of risk and protection of second anterior cruciate ligament injury. METHODS: One hundred and forty-five patients for return-to-sport testing after anterior cruciate ligament (ACL) reconstruction (ACLR) were contacted, and 97 were deemed eligible. All were evaluated between 6 and 24 months and followed up for 2 years. Participants answered the International Knee Documentation Committee (IKDC) and Anterior Cruciate Ligament-Return to Sport after Injury Scale (ACL-RSI), performed the postural stability assessment using the Biodex Balance System, and assessed muscle strength at 60° and 300°/s on the isokinetic dynamometer. Personal factors (age, gender, body mass index), body structures (graft type and concomitant injuries), and environmental factors (time between surgery and evaluation) were also collected. The participants were asked about the occurrence of a second ACL injury and return to sport after 2 years of follow-up. Classification and regression tree (CART) analysis was used to determine predictors of a second ACL injury. The receiver operating characteristic (ROC) curve was performed to verify the accuracy of the CART analysis, in addition to the sensitivity, specificity, and relative risk (RR) of the model. RESULTS: Of the initial 97 participants, 88 (89.8%) responded to follow-up and 14 (15.9%) had a second ACL injury (11 graft ruptures and three contralateral ACL). CART analysis identified the following variables as predictors of second ACL injury: return to sport, hamstring strength symmetry at 300°/s, ACL-RSI score, hamstrings/quadriceps ratio at 60°/s, and body mass index (BMI). CART correctly identified 9 (64.3%) of the 14 participants who were reinjured and 71 (95.9%) of the 74 participants who were not. The total correct classification was 90.9%. The area under the ROC curve was 0.88 (95% CI 0.72-0.99; p < 0.001), and the model showed a sensitivity of 75% (95% CI 42.8-94.5), specificity of 93.4% (95% CI 85.3-97.8), and RR of 15.9 (95% CI 4.9-51.4; p < 0.0001). CONCLUSION: The combination of hamstring strength symmetry, hamstring/quadriceps ratio (body functions); return to sport (activity and participation); psychological readiness; and BMI (personal factors) could identify three clinical risk profiles for a second ACL injury with good accuracy. LEVEL OF EVIDENCE: IV.

19.
Anim Reprod ; 20(2): e20230092, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37720727

RESUMO

Currently, gonadotropin products (follicle stimulating hormone, FSH, and luteinizing hormone, LH) used in animal reproduction are produced by extraction and purification from abattoir-derived pituitary glands. This method, relying on animal-derived materials, carries the potential risk of hormone contamination and pathogen transmission. Additionally, chorionic gonadotropins are extracted from the blood of pregnant mares (equine chorionic gonadotropin; eCG) or the urine of pregnant women (human chorionic gonadotropin; hCG). However, recent advancements have introduced recombinant gonadotropins for assisted animal reproduction therapies. The traditional use of FSH for superovulation has limitations, including labor requirements and variability in superovulation response, affecting the success of in vivo (SOV) and in vitro (OPU/IVEP) embryo production. FSH treatment for superstimulation before OPU can promote the growth of a homogenous follicular population and the recovery of competent oocytes suitable for IVEP procedures. At present, a single injection of a preparation of long-acting bovine recombinant FSH (rFSH) produced similar superovulation responses resulting in the production of good-quality in vivo and in vitro embryos. Furthermore, the treatment with eCG at FTAI protocol has demonstrated its efficacy in promoting follicular growth, ovulation, and P/AI, mainly in heifers and anestrous cows. Currently, treatment with recombinant glycoproteins with eCG-like activity (r-eCG) have shown promising results in increasing follicular growth, ovulation, and P/AI in cows submitted to P4/E2 -based protocols. Bovine somatotropin (bST) is a naturally occurring hormone found in cows. Recombinant bovine somatotropin (rbST), produced through genetic engineering techniques, has shown potential in enhancing reproductive outcomes in ruminants. Treatment with rbST has been found to improve P/IA, increase donor embryo production, and enhance P/ET in recipients. The use of recombinant hormones allows to produce non-animal-derived products, offering several advantages in assisted reproductive technologies for ruminants. This advancement opens up new possibilities for improving reproductive efficiency and success rates in the field of animal reproduction.

20.
Molecules ; 28(16)2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37630195

RESUMO

Schistosomiasis is a tropical disease transmitted in an aqueous environment by cercariae from the Schistosoma genus. This disease affects 200 million people living in risk areas around the world. The control of schistosomiasis is realized by chemotherapy, wastewater sanitation, health education, and mollusk control using molluscicidal agents. This work evaluates the effects of a nanoemulsion containing essential oil from Myrciaria floribunda leaves as a molluscicidal and cercaricidal agent against Biomphalaria glabrata mollusks and Schistosoma mansoni cercariae. The Myrciaria floribunda essential oil from leaves showed nerolidol, ß-selinene, 1,8 cineol, and zonarene as major constituents. The formulation study suggested the F3 formulation as the most promising nanoemulsion with polysorbate 20 and sorbitan monooleate 80 (4:1) with 5% (w/w) essential oil as it showed a smaller droplet size of approximately 100 nm with a PDI lower than 0.3 and prominent bluish reflection. Furthermore, this nanoemulsion showed stability after 200 days under refrigeration. The Myrciaria floribunda nanoemulsion showed LC50 values of 48.11 µg/mL, 29.66 µg/mL, and 47.02 µg/mL in Biomphalaria glabrata embryos, juveniles, and adult mollusks, respectively, after 48 h and 83.88 µg/mL for Schistosoma mansoni cercariae after 2 h. In addition, a survival of 80% was observed in Danio rerio, and the in silico toxicity assay showed lower overall human toxicity potential to the major compounds in the essential oil compared to the reference molluscicide niclosamide. These results suggest that the nanoemulsion of Myrciaria floribunda leaves may be a promising alternative for schistosomiasis control.


Assuntos
Moluscocidas , Myrtaceae , Óleos Voláteis , Adulto , Humanos , Óleos Voláteis/farmacologia , Moluscocidas/farmacologia , Eucaliptol , Niclosamida , Alimentos
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