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1.
Small ; 20(19): e2309230, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38112271

RESUMO

Bone infection poses a major clinical challenge that can hinder patient recovery and exacerbate postoperative complications. This study has developed a bioactive composite scaffold through the co-assembly and intrafibrillar mineralization of collagen fibrils and zinc oxide (ZnO) nanowires (IMC/ZnO). The IMC/ZnO exhibits bone-like hierarchical structures and enhances capabilities for osteogenesis, antibacterial activity, and bacteria-infected bone healing. During co-cultivation with human bone marrow mesenchymal stem cells (BMMSCs), the IMC/ZnO improves BMMSC adhesion, proliferation, and osteogenic differentiation even under inflammatory conditions. Moreover, it suppresses the activity of Gram-negative Porphyromonas gingivalis and Gram-positive Streptococcus mutans by releasing zinc ions within the acidic infectious microenvironment. In vivo, the IMC/ZnO enables near-complete healing of infected bone defects within the intricate oral bacterial milieu, which is attributed to IMC/ZnO orchestrating M2 macrophage polarization, and fostering an osteogenic and anti-inflammatory microenvironment. Overall, these findings demonstrate the promise of the bioactive scaffold IMC/ZnO for treating bacteria-infected bone defects.


Assuntos
Regeneração Óssea , Colágeno , Células-Tronco Mesenquimais , Nanofios , Osteogênese , Alicerces Teciduais , Óxido de Zinco , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Nanofios/química , Regeneração Óssea/efeitos dos fármacos , Alicerces Teciduais/química , Humanos , Colágeno/química , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Animais , Porphyromonas gingivalis/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Streptococcus mutans/fisiologia , Streptococcus mutans/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos
2.
Nat Commun ; 14(1): 6963, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37907455

RESUMO

Infected bone defects are a major challenge in orthopedic treatment. Native bone tissue possesses an endogenous electroactive interface that induces stem cell differentiation and inhibits bacterial adhesion and activity. However, traditional bone substitutes have difficulty in reconstructing the electrical environment of bone. In this study, we develop a self-promoted electroactive mineralized scaffold (sp-EMS) that generates weak currents via spontaneous electrochemical reactions to activate voltage-gated Ca2+ channels, enhance adenosine triphosphate-induced actin remodeling, and ultimately achieve osteogenic differentiation of mesenchymal stem cells by activating the BMP2/Smad5 pathway. Furthermore, we show that the electroactive interface provided by the sp-EMS inhibits bacterial adhesion and activity via electrochemical products and concomitantly generated reactive oxygen species. We find that the osteogenic and antibacterial dual functions of the sp-EMS depend on its self-promoting electrical stimulation. We demonstrate that in vivo, the sp-EMS achieves complete or nearly complete in situ infected bone healing, from a rat calvarial defect model with single bacterial infection, to a rabbit open alveolar bone defect model and a beagle dog vertical bone defect model with the complex oral bacterial microenvironment. This translational study demonstrates that the electroactive bone graft presents a promising therapeutic platform for complex defect repair.


Assuntos
Osteogênese , Alicerces Teciduais , Ratos , Animais , Coelhos , Cães , Biomimética , Regeneração Óssea , Diferenciação Celular , Bactérias
3.
World J Surg ; 47(6): 1548-1561, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36882637

RESUMO

BACKGROUND: Liver cancer resection is an effective but complex way to treat liver cancer, and complex anatomy is one of the reasons for the difficulty of surgery. The use of 3D technology can help surgeons cope with this dilemma. This article intends to conduct a bibliometric analysis of the role of 3D technology in liver cancer resection. METHODS: (TS = (3D) OR TS = (three-dimensional)) AND (TS = (((hepatic) OR (liver)) AND ((cancer) OR (tumor) OR (neoplasm)))) AND (TS = (excision) OR TS = (resection)) was used as a search strategy for data collection in the Web of Science (WoS) Core Collection. CiteSpace, Carrot2 and Microsoft Office Excel were used for data analysis. RESULTS: Three hundred and eighty-eight relevant articles were obtained. Their annual and journal distribution maps were produced. Countries/regions and institutions collaboration, author collaboration, references co-citations and their clusters and keywords co-occurrences and their clusters were constructed. Carrot2 cluster analysis was performed. CONCLUSIONS: There was an overall upward trend in the number of publications. China's contribution was greater, and the USA had greater influence. Southern Med Univ was the most influential institution. However, the cooperation between institutions still needs to be further strengthened. Surgical Endoscopy and Other Interventional Techniques was the most published journal. Couinaud C and Soyer P were the authors with the highest citations and centrality, respectively. "Liver planning software accurately predicts postoperative liver volume and measures early regeneration" was the most influential article. 3D printing, 3D CT and 3D reconstruction may be the mainstream of current research, and augmented reality (AR) may be a future hot spot.


Assuntos
Hepatectomia , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/cirurgia , Tecnologia , Bibliometria
4.
Int J Mol Sci ; 23(22)2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36430435

RESUMO

Apart from the well-established role of the gonadotropin-inhibitory hormone (GnIH) in the regulation of the reproductive functions, much less is known about the peripheral role of the GnIH and its receptor in the metabolic processes. On account of pig being an excellent model for studies of food intake and obesity in humans, we investigated the peripheral effects of the GnIH on food intake and energy homeostasis and revealed the underlying mechanism(s) in female piglets in vivo. Compared to the vehicle-treated group, intraperitoneally injected GnIH significantly increased the food intake and altered the meal microstructure both in the fasting and ad libitum female piglet. GnIH-triggered hyperphagia induced female piglet obesity and altered islet hormone secretion in the pancreas, accompanied with dyslipidemia and hyperglycemia. Interestingly, GnIH decreased the glucose transport capacity and glycogen synthesis, whereas it increased the gluconeogenesis in the liver, while it also induced an insulin resistance in white adipose tissue (WAT) via inhibiting the activity of AKT-GSK3-ß signaling. In terms of the lipid metabolism, GnIH reduced the oxidation of fatty acids, whereas the elevated fat synthesis ability in the liver and WAT was developed though the inhibited AMPK phosphorylation. Our findings demonstrate that peripheral GnIH could trigger hyperphagia-induced obesity and an associated glycolipid metabolism disorder in female piglets, suggesting that GnIH may act as a potential therapeutic agent for metabolic syndrome, obesity and diabetes.


Assuntos
Hormônios Hipotalâmicos , Humanos , Animais , Feminino , Suínos , Hormônios Hipotalâmicos/fisiologia , Quinase 3 da Glicogênio Sintase , Gonadotropinas , Hiperfagia , Obesidade/etiologia
5.
Int J Mol Sci ; 23(15)2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35897643

RESUMO

Gonadotropin-inhibitory hormone (GnIH) is a reproductive inhibitor and an endogenous orexigenic neuropeptide that may be involved in energy homeostasis and reproduction. However, whether GnIH is a molecular signal link of metabolism and the reproductive system, and thus, regulates reproductive activity as a function of the energy state, is still unknown. In the present study, we investigated the involvement of GnIH in glycolipid metabolism and reproduction in vivo, and in the coupling between these two processes in the testis level. Our results showed that chronic intraperitoneal injection of GnIH into male mice not only increased food intake and altered meal microstructure but also significantly elevated body mass due to the increased mass of liver and epididymal white adipose tissue (eWAT), despite the loss of testicular weight. Furthermore, chronic intraperitoneal administration of GnIH to male mice resulted in obesity-related glycolipid metabolic derangements, showing hyperlipidemia, hyperglycemia, glucose intolerance, and insulin resistance through changes in the expression of glucose and lipid metabolism-related genes in the pancreas and eWAT, respectively. Interestingly, the expression of GnIH and GPR147 was markedly increased in the testis of mice under conditions of energy imbalance, such as fasting, acute hypoglycemia, and hyperglycemia. In addition, chronic GnIH injection markedly inhibited glucose and lipid metabolism of mice testis while significantly decreasing testosterone synthesis and sperm quality, inducing hypogonadism. These observations indicated that orexigenic GnIH triggers hyperphagia-induced obesity-related metabolic derangements and hypogonadism in male mice, suggesting that GnIH is an emerging candidate for coupling metabolism and fertility by involvement in obesity and metabolic disorder-induced reproductive dysfunction of the testes.


Assuntos
Hiperglicemia , Hipogonadismo , Hormônios Hipotalâmicos , Animais , Glucose , Glicolipídeos , Gonadotropinas , Hiperfagia/complicações , Hipogonadismo/etiologia , Hormônios Hipotalâmicos/genética , Masculino , Camundongos , Obesidade/complicações , Sêmen/metabolismo
6.
Chem Commun (Camb) ; 58(15): 2468-2471, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35024704

RESUMO

We report a new osmium(VI) nitrido complex bearing a nonplanar tetradentate ligand with potent anticancer activity. This complex causes mitochondrial damage, which induces liver cancer cell death via oncosis and apoptosis. This is the first osmium-based anticancer candidate that induces oncosis.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Mitocôndrias/efeitos dos fármacos , Nitrilas/farmacologia , Osmio/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Mitocôndrias/metabolismo , Estrutura Molecular , Nitrilas/química , Osmio/química
7.
Dalton Trans ; 49(47): 17173-17182, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33119012

RESUMO

The osmium(vi) nitrido complex [OsVI(N)(sap)(py)Cl] is a potential anti-cancer drug with promising in vitro antiproliferative activities toward a panel of cancer cell lines, including cisplatin-resistant cells (IC50 values of 2.8-13.8 µM). This drug targets DNA and changes its conformation via covalent binding and insertion. In vitro studies indicate that the drug induces HepG2 cells G2/M phase arrest, disrupts the mitochondrial membrane potential and causes caspase-mediated apoptosis. Further in vivo studies using HepG2-bearing nude mice reveal that this drug not only shows good antitumor efficacy of inhibiting tumor growth, but also does not show the side effect of weight loss.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Complexos de Coordenação/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/metabolismo , Neoplasias Hepáticas Experimentais/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Nus , Modelos Moleculares , Estrutura Molecular , Nitrilas/química , Nitrilas/farmacologia , Osmio/química , Osmio/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
8.
ACS Nano ; 13(6): 6581-6595, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31125522

RESUMO

The host immune response to bone biomaterials is vital in determining scaffold fates and bone regeneration outcomes. The nanometer-scale interface of biomaterials, which independently controls physical inputs to cells, regulates osteogenic differentiation of stem cells and local immune response. Herein, we fabricated biomimetic hierarchical intrafibrillarly mineralized collagen (HIMC) with a bone-like staggered nanointerface and investigated its immunomodulatory properties and mesenchymal stem cell (MSC) recruitment during endogenous bone regeneration. The acquired HIMC potently induced neo-bone formation by promoting CD68+CD163+ M2 macrophage polarization and CD146+STRO-1+ host MSC recruitment in critical-sized bone defects. Mechanistically, HIMC facilitated M2 macrophage polarization and interleukin (IL)-4 secretion to promote MSC osteogenic differentiation. An anti-IL4 neutralizing antibody significantly reduced M2 macrophage-mediated osteogenic differentiation of MSCs. Moreover, HIMC-loaded-IL-4 implantation into critical-sized mandible defects dramatically enhanced bone regeneration and CD68+CD163+ M2 macrophage polarization. The depletion of monocyte/macrophages by clodronate liposomes significantly impaired bone regeneration by HIMC, but did not affect MSC recruitment. Thus, in emulating natural design, the hierarchical nanointerface possesses the capacity to recruit host MSCs and promote endogenous bone regeneration by immunomodulation of macrophage polarization through IL-4.


Assuntos
Materiais Biomiméticos/química , Regeneração Óssea , Macrófagos/metabolismo , Células-Tronco Mesenquimais/citologia , Nanoconjugados/química , Alicerces Teciduais/química , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/metabolismo , Materiais Biomiméticos/farmacologia , Cálcio/química , Diferenciação Celular , Células Cultivadas , Colágeno/química , Humanos , Interleucina-4/química , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Células THP-1
9.
Pharm Dev Technol ; 24(6): 794-802, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30907676

RESUMO

In this study, reduction-sensitive self-assembled polymer nanoparticles based on poly (lactic-co-glycolic acid) (PLGA) and chondroitin sulfate A (CSA) were developed and characterized. PLGA was conjugated with CSA via a disulfide linkage (PLGA-ss-CSA). The critical micelle concentration (CMC) of PLGA-ss-CSA conjugate is 3.5 µg/mL. The anticancer drug doxorubicin (DOX) was chosen as a model drug, and was effectively encapsulated into the nanoparticles (PLGA-ss-CSA/DOX) with high loading efficiency of 15.1%. The cumulative release of DOX from reduction-sensitive nanoparticles was only 34.8% over 96 h in phosphate buffered saline (PBS, pH 7.4). However, in the presence of 20 mM glutathione-containing PBS environment, DOX release was notably accelerated and almost complete from the reduction-sensitive nanoparticles up to 96 h. Moreover, efficient intracellular DOX release of PLGA-ss-CSA/DOX nanoparticles was confirmed by CLSM assay in A549 cells. In vitro cytotoxicity study showed that the half inhibitory concentrations of PLGA-ss-CSA/DOX nanoparticles and free DOX against A549 cells were 1.141 and 1.825 µg/mL, respectively. Therefore, PLGA-ss-CSA/DOX nanoparticles enhanced the cytotoxicity of DOX in vitro. These results suggested that PLGA-ss-CSA nanoparticles could be a promising carrier for drug delivery.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Sulfatos de Condroitina/química , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/análogos & derivados , Células A549 , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacologia , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Humanos , Neoplasias/tratamento farmacológico
10.
Int J Radiat Biol ; 91(5): 420-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25651040

RESUMO

PURPOSE: To investigate whether extremely low frequency electromagnetic field (ELF-EMF) exposure could induce oxidative stress in workers performing tour-inspection near transformers and distribution power lines. MATERIALS AND METHODS: Occupational short-term 'spot' measurements were performed. In total, 310 inspection workers exposed to ELF-EMF were selected as the exposure group and 300 logistical staff as the control group. Plasma total antioxidant capacity (T-AOC) and glutathione peroxidase (GPx) activity were tested by the colorimetric method. Superoxide dismutase (SOD) activity was tested using the xanthine oxidase method. Plasma malondialdehyde (MDA) concentration was determined with a thiobarbituric acid assay. The micronucleus cell frequency (MCF) and Micronuclei frequency (MN) were also tested for genotoxic assessment. RESULTS: No significant changes of enzyme activities or MDA concentration were found. Neither the frequency of micronucleus lymphocytes nor micronuclei frequency changes were statistically significant. CONCLUSION: Continual ELF-EMF exposure might not induce oxidative stress in workers from a power supply bureau.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Exposição Ocupacional/efeitos adversos , Estresse Oxidativo/efeitos da radiação , Adulto , Biomarcadores/sangue , Estudos Transversais , Fontes de Energia Elétrica , Humanos , Masculino
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