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1.
Int J Biol Macromol ; 271(Pt 1): 132564, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38782324

RESUMO

Recently, the incidence of Achilles tendon ruptures (ATRs) has become more common, and repair surgery using a bioabsorbable suture is generally preferred, particularly in the case of healthy patients. Sutures composed of poly(lactic-co-glycolic acid) (PLGA) are commonly used in ATR surgeries. Nevertheless, owing to the inherent limitations of PLGA, novel bioabsorbable sutures that can accelerate Achilles tendon healing are sought. Recently, several studies have demonstrated the beneficial effects of atelocollagen on tendon healing. In this study, poly(3,4-dihydroxy-L-phenylalanine) (pDOPA), a hydrophilic biomimetic material, was used to modify the hydrophobic surface of a PLGA suture (Vicryl, VC) for the stable coating of atelocollagen on its surface. The main objective was to fabricate an atelocollagen-coated VC suture and evaluate its performance in the healing of Achilles tendon using a rat model of open repair for ATR. Structural analyses of the surface-modified suture indicated that the collagen was successfully coated on the VC/pDOPA suture. Postoperative in vivo biomechanical analysis, histological evaluation, ultrastructural/morphological analyses, and western blotting confirmed that the tendons in the VC/pDOPA/Col group exhibit superior healing than those in the VC and VC/pDOPA groups after 1 and 6 weeks following the surgery. The this study suggests that atelocollagen-coated PLGA/pDOPA sutures are preferable for future medical applications, especially in the repair of ATR.


Assuntos
Tendão do Calcâneo , Colágeno , Suturas , Cicatrização , Animais , Tendão do Calcâneo/cirurgia , Tendão do Calcâneo/efeitos dos fármacos , Tendão do Calcâneo/lesões , Ratos , Cicatrização/efeitos dos fármacos , Colágeno/química , Masculino , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Implantes Absorvíveis , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Ratos Sprague-Dawley , Modelos Animais de Doenças , Regeneração/efeitos dos fármacos , Traumatismos dos Tendões/cirurgia
2.
Int J Biol Macromol ; 253(Pt 5): 127154, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37793524

RESUMO

The rising demand for green and clean energy urges the enlargement of economical and proficient electrode materials for supercapacitors. Herein, we designed a novel electrode material by porous cellulose graphitic carbon (CC) derived from bio-waste cornhusk via the pyrolysis route, and α-Fe2O3 decorated nanostructure with CC (CCIO) was achieved in situ pyrolysis of corn-husk and Fe(NO3)3·9H2O metal salt followed by a coating of polypyrrole (CCIOP). The CC, CCIO, and CCIOP nanocomposite electrodes were characterized by XRD, Raman, FTIR, FE-SEM/EDX, FE-TEM, XPS, and BET analysis. The CCIOP nanocomposite electrode exhibits an enhanced specific capacitance (Csp) of 290.9 F/g, which is substantial to its pristine CC (128.3 F/g), PPy (140.3 F/g), and CCIO (190.7 F/g). The Csp of CCIOP in a three-electrode system, using 1 M Na2SO4 electrolyte exhibits excellent capacity retention of 79.1 % even at a high current density of 10 A/g. The as-fabricated asymmetric supercapacitor (ASC) delivered a remarkable capacity retention of 88.7 % with a coulombic efficiency of 98.8 % even after 3000 cycles. The study shows successful utilization of cellulose from bio-waste cornhusk into a substantial template applicable in future alternative energy storage devices.


Assuntos
Grafite , Nanocompostos , Polímeros , Celulose , Carbono , Pirróis , Eletrodos
3.
Artigo em Inglês | MEDLINE | ID: mdl-36612326

RESUMO

As the most successful platform for peer-based accommodation sharing, Airbnb has transformed the lodging industry into something much more affordable and accessible for travelers on a budget. Compared to a hotel stay, however, its variability of facility and service has created guests' negative emotions such as regret and dissatisfaction. These emotions may cause stress, which negatively affect mental health. Therefore, we explore the factors that influence Airbnb guests' regret, and investigate the relationship between their regret, dissatisfaction, and negative behavioral intention. Structural equation model is utilized on a total of 456 U.S. consumers to examine the relationship among Airbnb users' responses. The findings indicate that price perception influences regret and dissatisfaction the most. The study also reveals that regret has a positive correlation with dissatisfaction, while does not have an influence on switching intention and negative word of mouth. Based on the result, theoretical and managerial implications are discussed.


Assuntos
Emoções , Intenção , Custos e Análise de Custo , Habitação
4.
Sci Rep ; 12(1): 5009, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35322150

RESUMO

Senecavirus A (SVA) is a cause of vesicular disease in pigs, and infection rates are rising within the swine industry. Recently, anthrax toxin receptor 1 (ANTXR1) was revealed as the receptor for SVA in human cells. Herein, the role of ANTXR1 as a receptor for SVA in pigs was investigated by CRISPR/Cas9 genome editing. Strikingly, ANTXR1 knockout (KO) pigs exhibited features consistent with the rare disease, GAPO syndrome, in humans. Fibroblasts from wild type (WT) pigs supported replication of SVA; whereas, fibroblasts from KO pigs were resistant to infection. During an SVA challenge, clinical symptoms, including vesicular lesions, and circulating viremia were present in infected WT pigs but were absent in KO pigs. Additional ANTXR1-edited piglets were generated that were homozygous for an in-frame (IF) mutation. While IF pigs presented a GAPO phenotype similar to the KO pigs, fibroblasts showed mild infection, and circulating SVA nucleic acid was decreased in IF compared to WT pigs. Thus, this new ANTXR1 mutation resulted in decreased permissiveness of SVA in pigs. Overall, genetic disruption of ANTXR1 in pigs provides a unique model for GAPO syndrome and prevents circulating SVA infection and clinical symptoms, confirming that ANTXR1 acts as a receptor for the virus.


Assuntos
Infecções por Picornaviridae , Picornaviridae , Doenças dos Suínos , Alopecia , Animais , Anodontia , Transtornos do Crescimento , Atrofias Ópticas Hereditárias , Fenótipo , Picornaviridae/genética , Doenças Raras , Receptores de Peptídeos , Suínos
5.
Anim Cells Syst (Seoul) ; 23(5): 335-345, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31700699

RESUMO

The present study investigated the cellular properties in the dental tissue-derived mesenchymal stem cells (DSCs) exposed to nevirapine (NVP), an inhibitor of reverse transcriptase (RTase). After a prolonged exposure of DSCs for 2 weeks, the population doubling time (PDT) was significantly (P < .05) increased by delayed cell growth in the DSCs treated with 250 and 500 µM NVP, compared with untreated DSCs. Furthermore, the G1 phase of cell cycle with high activity of senescence-associated ß-galactosidase was also significantly (P < .05) increased in the 250 µM NVP-treated DSCs, compared with untreated DSCs. The level of telomerase activity was unchanged between control and treatment. However, following the treatment of NVP, negative surface markers for mesenchymal stem cells (MSCs), such as CD34 and CD45, were significantly (P < .05) increased, while positive surface markers for MSCs, such as CD90 and CD105, were significantly (P < .05) decreased in the NVP-treated DSCs than those of untreated DSCs. Furthermore, the differentiation capacity into mesodermal lineage was gradually decreased, and a significant (P < .05) decrease of expression level of NANOG, OCT-4 and SOX-2 transcripts was observed in the DSCs treated with NVP, compared with untreated control DSCs. Taken together, the present results have revealed that inhibition of RTase by NVP induces delayed cell growth and loss of stemness.

6.
Bioresour Technol ; 261: 420-427, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29698891

RESUMO

Enormous disposal of paper wastes (PW) causing number of environmental problems. PW is efficiently used to extract multifunctional α-cellulose fibers (αCFs). Thus, αCFs extraction from PW, and functionalization with Fe3O4 and chitosan were successfully performed for immobilization of laccase. Therefore, in this investigation, PW extracted αCFs were tuned with supermagnetic Fe3O4 (M) and functionalized with chitosan (CTA) (M-PW-αCF-CTA). Furthermore, M-PW-αCF-CTA was glutaraldehyde cross-linked for covalent laccase immobilization. The synthesized materials were characterized by FT-IR, TGA, FE-SEM, FE-HR-TEM and VSM analyzes. M-PW-αCF-CTA exhibited magnetic saturation value of 14.72 emu/g. Laccase immobilized on M-PW-αCF-CTA (M-PW-αCF-CTA-Lac) gave 92% of activity recovery and loading capacity of 73.30 mg/g. M-PW-αCF-CTA-Lac showed excellent pH, temperature, and storage stabilities with the exceptional reusability potential. Moreover, M-PW-αCF-CTA-Lac was applied for repeated removal of carcinogenic Direct Red 28 (DR28). Therefore, M-PW-αCF-CTA-Lac is green and economical biocatalyst with extraordinary separation potential can be enforced for environmental pollutants reclamation.


Assuntos
Celulose , Poluentes Ambientais/metabolismo , Enzimas Imobilizadas , Lacase/metabolismo , Quitosana , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Cell Reprogram ; 12(2): 141-50, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20677929

RESUMO

Three viable female dogs, which have the same genotype, have been successfully produced by somatic cell nuclear transfer (SCNT); however, data on the growth pattern of cloned dogs are lacking. Thus, the aim of this study was (1) to assess growth parameters among those cloned dogs with measurement of body weight, height, and radiographic analysis of skull size and bone plate, and (2) to compare hematologic characteristics among the donor dog, cloned dogs, and age-matched control dogs. The cloned dogs were kept in the same environmental conditions. The body weight increased from 0.52, 0.46, and 0.52 kg at birth to 21.9, 22.9, and 20.4 kg at 68 weeks of age for individual cloned dogs, respectively. The withers height increased from 34.5, 32.6, and 35.2 cm at 8 weeks of age to 67.1 cm at 68 weeks of age in the three clones. The radiographic data demonstrated that patterns of bone growth were similar among cloned dogs, and all measured parameters of matured cloned dogs were similar with that of the fully grown donor dog. An age-specific pattern was identified on hematologic and serum biochemical measurements in both cloned dogs and age-matched controls. The parameters examined were within the normal reference ranges for healthy dogs. In conclusion, three genetically identical cloned dogs showed similar growth characteristics and had normal hematological and serum biochemical parameters.


Assuntos
Clonagem de Organismos/métodos , Técnicas de Transferência Nuclear , Animais , Contagem de Células Sanguíneas , Tamanho Corporal , Peso Corporal , Osso e Ossos/diagnóstico por imagem , Clonagem de Organismos/veterinária , Cães , Eritrócitos/imunologia , Feminino , Oócitos/citologia , Radiografia , Fatores de Tempo , Dente/fisiologia
8.
Biomacromolecules ; 4(4): 1013-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12857086

RESUMO

Small angle neutron scattering studies have been carried out on cellulose fibers from ramie and Populus maximowicii (cotton wood). Labile hydrogen atoms were replaced by deuterium atoms, in water-accessible disordered regions of the fibers, to increase the neutron scattering contrast between the disordered and crystalline regions. A meridional Bragg reflection, corresponding to a longitudinal periodicity of 150 nm, was observed when scattering collected from hydrogenated and deuterated dry ramie fibers was subtracted. No Bragg reflection was observed with the cotton wood fibers, probably because of lower orientation of the microfibrils in the cell wall. The ramie fibers were then subjected to electron microscopy, acid hydrolysis, gel permeation chromatography, and viscosity studies. The leveling off degree of polymerization (LODP) of the hydrolyzed samples matched exactly the periodicity observed in the diffraction studies. The weight loss related to the LODP was only about 1.5%, and thus, the microfibrils can be considered to have 4-5 disordered residues every 300 residues.


Assuntos
Boehmeria/química , Celulose/química , Microfibrilas/química , Ácidos/química , Boehmeria/ultraestrutura , Parede Celular/química , Parede Celular/ultraestrutura , Celulose/ultraestrutura , Cromatografia em Gel , Deutério/química , Hidrogênio/química , Concentração de Íons de Hidrogênio , Hidrólise , Microfibrilas/ultraestrutura , Microscopia Eletrônica de Varredura , Nêutrons , Espalhamento de Radiação , Viscosidade
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