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1.
Adv Sci (Weinh) ; 11(16): e2307683, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38358041

RESUMO

Osteoarthritis (OA) is the most common degenerative joint disease worldwide, with the main pathological manifestation of articular cartilage degeneration. It have been investigated that pharmacological activation of transient receptor potential vanilloid 1 (TRPV1) significantly alleviated cartilage degeneration by abolishing chondrocyte ferroptosis. In this work, in view of the thermal activated feature of TRPV1, Citrate-stabilized gold nanorods (Cit-AuNRs) is conjugated to TRPV1 monoclonal antibody (Cit-AuNRs@Anti-TRPV1) as a photothermal switch for TRPV1 activation in chondrocytes under near infrared (NIR) irradiation. The conjugation of TRPV1 monoclonal antibody barely affect the morphology and physicochemical properties of Cit-AuNRs. Under NIR irradiation, Cit-AuNRs@Anti-TRPV1 exhibited good biocompatibility and flexible photothermal responsiveness. Intra-articular injection of Cit-AuNRs@Anti-TRPV1 followed by NIR irradiation significantly activated TRPV1 and attenuated cartilage degradation by suppressing chondrocytes ferroptosis. The osteophyte formation and subchondral bone sclerosis are remarkably alleviated by NIR-inspired Cit-AuNRs@Anti-TRPV1. Furthermore, the activation of TRPV1 by Cit-AuNRs@Anti-TRPV1 evidently improved physical activities and alleviated pain of destabilization of the medial meniscus (DMM)-induced OA mice. The study reveals Cit-AuNRs@Anti-TRPV1 under NIR irradiation protects chondrocytes from ferroptosis and attenuates OA progression, providing a potential therapeutic strategy for the treatment of OA.


Assuntos
Condrócitos , Ouro , Nanotubos , Osteoartrite , Animais , Masculino , Camundongos , Condrócitos/metabolismo , Condrócitos/efeitos dos fármacos , Modelos Animais de Doenças , Progressão da Doença , Ouro/química , Raios Infravermelhos , Camundongos Endogâmicos C57BL , Nanotubos/química , Osteoartrite/metabolismo , Osteoartrite/tratamento farmacológico , Canais de Cátion TRPV/metabolismo
2.
Research (Wash D C) ; 7: 0316, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371274

RESUMO

Transient receptor potential vanilloid family member 1 (TRPV1) has been revealed as a therapeutic target of osteoarthritis (OA), the most common deteriorating whole joint disease, by impeding macrophagic inflammation and chondrocytes ferroptosis. However, the clinical application for capsaicin as the TRPV1 agonist is largely limited by its chronic toxicity. To address this issue, we developed a bifunctional controllable magnetothermal switch targeting TRPV1 for the alleviation of OA progression by coupling of magnetic nanoparticles (MNPs) to TRPV1 monoclonal antibodies (MNPs-TRPV1). Under the alternating magnetic field (AMF) stimulation, MNPs-TRPV1 locally dissipated heat, which was sufficient to trigger the opening and activation of TRPV1, and effectively impeded macrophagic inflammation and chondrocyte ferroptosis. This magnetothermal modulation of TRPV1 simultaneously attenuated synovitis and cartilage degeneration in mice incurred by destabilization of medial meniscus surgery, indicating the delayed OA progression. Furthermore, MNPs-TRPV1 with AMF exposure remarkably reduced knee pain sensitivity, alleviated the crippled gait, and improved spontaneous ambulatory activity performance in the mice OA model. Overall, this work provides a potential pathogenesis-based precise OA therapy with temporally and spatially magnetothermal modulation of TRPV1 in a controllable manner.

3.
Bioresour Technol ; 377: 128935, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36958683

RESUMO

This study aimed to elucidate the multiple strategies employed by anaerobes during granulation in a laboratory upflow anaerobic sludge blanket reactor, based on microbial succession and interactions. The anaerobic granulation process featured staged dominance of microbial genera, corresponding well with the environmental traits. Across the stages (selection, seeding, expansion, and maturation), chemotaxis attraction of nitrogen and/or carbon sources and flagellar motion were the primary strategy of microbial assembly. The second messengers - cyclic adenosine and guanosine monophosphates - partially regulated the agglomeration of filamentous Euryachaeota and Chloroflexi as the inner cores, while quorum sensing mediated the expansion of granules prior to maturation. Antagonism or competition governed the interactions within the phylogenetic molecular ecological network during sludge granulation, which were largely driven by the low-abundance (<1%) taxa. These new insights suggest that better engineering solutions to enhance chemotaxis attraction and species selection could achieve more efficient anaerobic granular sludge processes.


Assuntos
Reatores Biológicos , Esgotos , Anaerobiose , Filogenia , Bactérias Anaeróbias
4.
Carbohydr Polym ; 300: 120252, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372483

RESUMO

Bacterial cellulose (BC) is a significant polysaccharide that bacteria create under specific growth conditions that exhibits high purity, high water-holding capacity, high crystallinity, strong mechanical capabilities, and high biocompatibility. Pure BC has been studied, marketed, and frequently combined with other materials to provide additional potential effects. Additionally, because of the abundance of hydroxyl groups in BC, it can be readily changed to yield derivatives or composites with improved physicochemical and functional characteristics for a variety of applications such as artificial blood vessel manufacturing, soft tissue engineering, and bone tissue engineering. In this review, state-of-the-art manufacturing, structural traits, and applications of BC are summarized, along with in situ and ex situ modification techniques and their biomedical applications. Finally, the future growth opportunities and obstacles for BC and its composites in the biological sector are anticipated.


Assuntos
Celulose , Engenharia Tecidual , Celulose/química , Bactérias/química , Materiais Biocompatíveis/química
5.
Int J Biol Macromol ; 222(Pt A): 994-1006, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36191783

RESUMO

Lignin is a major phenolic polymer from the plant biomass. Due to its abundant functional groups (carboxyl and hydroxyl groups), lignin could act as an antioxidant, antimicrobial as well as an immune modulator. These remarkable biological properties render lignin a highly potential bioactive candidate in the biomedical applications including tissue engineering. Although several effective applications of lignin-based composites have been reported in tissues repairing and organ regeneration, a systematic review to summarize the recent utilization of lignin-based composites in different tissue engineering fields is still lacking. Hence, the aim of this review is to delineate the biological functions of lignin and to highlight the latest applications of lignin-based composites in different tissue engineering fields, such as bone regeneration, organ regeneration and wound dressing. This review will serve as an illuminating resource to direct and promote the biomedical applications of lignin and lignin-based composites.


Assuntos
Lignina , Engenharia Tecidual , Regeneração Óssea , Polímeros , Biomassa
6.
Int J Biol Macromol ; 212: 547-560, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35643155

RESUMO

Lignin, the most abundant natural and sustainable phenolic compound in biomass, has exhibited medicinal values due to its biological activities decided by physicochemical properties. Recently, the lignin and its derivatives (such as lignosulfonates and lignosulfonate) have been proven efficient in regulating cellular process and the extracellular microenvironment, which has been regarded as the key factor in disease progression. In orthopaedic diseases, especially the degenerative diseases represented by osteoarthritis and osteoporosis, excessive activated inflammation has been proven as a key stage in the pathological process. Due to the excellent biocompatibility, antibacterial and antioxidative activities of lignin and its derivatives, they have been applied to stimulate cells and restore the uncoupling bone remodeling in the degenerative orthopaedic diseases. However, there is a lack of a systemic review to state the current research actuality of lignin and lignin-derived compounds in treating degenerative orthopaedic diseases. Herein, we summarized the current application of lignin and lignin-derived compounds in orthopaedic diseases and proposed their possible therapeutic mechanism in treating degenerative orthopaedic diseases. It is hoped this work could guide the future preparation of lignin/lignin-derived drugs and implants as available therapeutic strategies for clinically degenerative orthopaedic diseases.


Assuntos
Lignina , Ortopedia , Biomassa , Lignina/farmacologia , Lignina/uso terapêutico , Fenóis
7.
Carbohydr Polym ; 270: 118342, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34364595

RESUMO

The naturally tight entanglement of fibers in bacterial cellulose (BC) results in low printability when BC is used as a bioink for printing scaffolds. In this study, neat BC was treated by TEMPO-mediated oxidation (TO-BC) and maleic acid (MA-BC) to prepare homogeneous BC dispersions to fabricate scaffolds for bone regeneration. Results showed that the treatments released individual fibrils in the corresponding uniform dispersions without impairing inherent crystalline properties. Compared with TO-BC, MA-BC hybridized with gelatin could endow the gel with improved rheological properties and compression modulus for 3D printing. Both TO-BC and MA-BC dispersions showed good osteoblast viability. However, MA-BC possessed more pronounced ability to express osteogenic marker genes and formation of mineralized nodules in vitro. Compared with TO-BC-based gelatin scaffolds, MA-BC-based gelatin scaffolds showed a better ability to stimulate the regeneration of rat calvaria, demonstrating a higher bone mineral density of newly formed bone and trabecular thickness in vivo.


Assuntos
Regeneração Óssea , Celulose/química , Gelatina/química , Polissacarídeos Bacterianos/química , Impressão Tridimensional , Alicerces Teciduais/química , Animais , Óxidos N-Cíclicos/química , Hidrogéis/química , Hidrólise , Maleatos/química , Camundongos , Nanofibras/química , Osteoblastos/metabolismo , Osteogênese , Oxirredução , Ratos , Crânio/metabolismo , Engenharia Tecidual/métodos
8.
Angew Chem Int Ed Engl ; 59(29): 12199-12205, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-32239787

RESUMO

Reported herein is the development of the first enantioselective monodentate ligand assisted Pd-catalyzed domino Heck carbonylation reaction with CO. The highly enantioselective domino Heck carbonylation of N-aryl acrylamides and various nucleophiles, including arylboronic acids, anilines, and alcohols, in the presence of CO was achieved. A novel monodentate phosphoramidite ligand, Xida-Phos, has been developed for this reaction and it displays excellent reactivity and enantioselectivity. The reaction employs readily available starting materials, tolerates a wide range of functional groups, and provides straightforward access to a diverse array of enantioenriched oxindoles having ß-carbonyl-substituted all-carbon quaternary stereocenters, thus providing a facile and complementary method for the asymmetric synthesis of bioactive hexahydropyrroloindole and its dimeric alkaloids.

9.
Biotechnol Biofuels ; 12: 189, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31384296

RESUMO

BACKGROUND: Prehydrolyzate, which is from the prehydrolysis process in dissolving pulps industry, contains various sugar-derived and lignin compounds such as xylooligosaccharides (XOS), gluco-oligosaccharides, xylose, glucose, and soluble lignin (S-L). The XOS has several beneficial effects on human physiology. XOS and S-L in prehydrolyzate are difficult to efficiently fractionate due to their similar molecular weights and water solubility. In this work, we proposed a sustainable and green process using polystyrene divinylbenzene (PS-DVB) resin to simultaneously separate and recover XOS and S-L. Enzymatic hydrolysis with endo-1,4-ß-xylanase and fermentation with P. stipites were sequentially applied to purify XOS to minimize xylose content as well as amplify contents of xylobiose and xylotriose. In addition, 2D-HSQC NMR was used to analyze the structural characteristics of XOS and S-L. Furthermore, the biological abilities of antioxidants and prebiotics of these fractions were investigated by scavenging radicals and cultivating intestinally beneficial bacterias, respectively. RESULTS: Results showed that PS-DVB resin could simultaneously separate XOS and solubilized lignin with excellent yields of 93.2% and 85.3%, respectively. The obtained XOS after being purified by enzymatic hydrolysis and fermentation contained 57.7% of xylobiose and xylotriose. 10.4% amount of inherent xylan was found in the S-L fraction obtained by PS-DVB resin separation. 2D-HSQC NMR revealed that lignin carbohydrate complexes existed in both XOS and S-L as covalent linkages between lignin and 4-O-methylglucuronoarabinoxylan. The biological application results showed that the antioxidant capacity of S-L was stronger than XOS, while XOS was superior in promoting growth of intestinal Bifidobacteria adolescentis and stimulating production of short-chain fatty acids by Lactobacillus acidophilus. CONCLUSIONS: The proposed strategy of sequentially combining hydrophobic resin separation, enzymatic hydrolysis, and fermentation was successfully demonstrated and resulted in simultaneous production of high-quality XOS and solubilized lignin. These biomass-derived products in prehydrolyzate can be regarded as value-adding prebiotics and antioxidants.

10.
Org Biomol Chem ; 16(23): 4333-4337, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29808898

RESUMO

A modular 2H-azirine synthesis from ketoxime acetates via Cs2CO3-mediated cyclization has been developed. The reaction utilizes easily available starting materials and provides a general synthetic route to 2,3-diaryl-2H-azirines in good to excellent yields under mild conditions, which is complementary to the conventional approaches for the synthesis of 2H-azirines. A gram-scale reaction was performed to demonstrate the scale-up applicability of this synthetic method. Importantly, 2H-azirines can be efficiently converted to various azaheterocycles.

11.
Hell J Nucl Med ; 19(1): 42-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26929939

RESUMO

OBJECTIVE: We present a case of systemic lupus erythematosus (SLE) related autoimmune haemolytic anaemia (AIHA) and lymphadenopathy. AIHA as a serious complication of SLE, requiring urgent appropriate management. The timely differential diagnosis between SLE with lymphadenopathy and lymphoma, primary and SLE-related AIHA often looms as practical challenge under clinical scenario. Fluorine-18 fluorodeoxyglucose position emission tomography/computed tomography ((18)F-FDG PET/CT) performed for fever of a known origin and for possible malignancy, showed increased (18)F-FDG uptake in lymph nodes, as well as increased spleen uptake, which was probably due to lymphoma. CONCLUSIONS: A symmetrically increased (18)F-FDG uptake in small lymph nodes with multiple serous cavity effusion helped the differential diagnosis between SLE related AIHA and lymphoma. In addition, PET/CT can visualize not only the degree of disease activity or the "burden of inflammation" but also the distribution of the disease in the entire body.


Assuntos
Anemia Hemolítica Autoimune/diagnóstico , Fluordesoxiglucose F18 , Lúpus Eritematoso Sistêmico/diagnóstico , Doenças Linfáticas/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adolescente , Anemia Hemolítica Autoimune/etiologia , Diagnóstico Diferencial , Feminino , Humanos , Lúpus Eritematoso Sistêmico/complicações , Doenças Linfáticas/etiologia , Imagem Multimodal/métodos , Compostos Radiofarmacêuticos , Imagem Corporal Total/métodos
12.
Genet Test Mol Biomarkers ; 20(4): 176-84, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26918371

RESUMO

OBJECTIVE: To investigate the potential prognostic roles of polymorphisms in the X-ray repair cross-complementing group 1 (XPCC1), xeroderma pigmentosum group D (XPD) and excision repair cross-complementing group 1 (ERCC1) genes for patients with hepatocellular carcinoma (HCC) receiving transcatheter arterial chemoembolization (TACE). METHODS: Clinical data and blood samples from 308 HCC patients receiving TACE were collected between January 2010 and December 2013. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RLFP) analyses was used to determine the genotypes of the XPCC1 (rs25487), XPD (rs13181) and ERCC1 (rs11615) genes. The relationships between the genotypes and the efficacy of TACE treatment were analyzed. RESULTS: The XRCCI rs25487 polymorphism was associated with a favorable prognosis in HCC patients receiving TACE (p = 0.006), and patients carrying variant genotypes (A/A + G/A) were associated with significantly reduced risk of death compared with those with the wild genotype (G/G) (HR = 0.556; 95% CI = 0.354-0.874). These findings were supported by Kaplan-Meier survival curve analysis showing that median survival time for patients with A/A + G/A genotypes was significantly longer compared with those with the G/G genotype (11.2 month vs. 8.0 months; log rank p = 0.006). Stratified analyses revealed that A/A + G/A genotypes of XRCC1 rs25487 are associated with significantly reduced risk of death compared with the G/G genotype in patients grouped by tumor size, portal vein tumor thrombus (PVTT), alpha-fetoprotein (AFP) and TNM stage (all p < 0.05). The ERCC1 rs13181 and XPD rs11615 polymorphisms were not predictive of clinical outcome for HCC patients receiving TACE (both p > 0.05). CONCLUSION: The XRCC1 rs25487 polymorphisms are prognostic for HCC patients receiving TACE. The ERCC1 and XPD polymorphisms had no relationship to the clinical outcomes.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Proteínas de Ligação a DNA/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Proteína Grupo D do Xeroderma Pigmentoso/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/mortalidade , Quimioembolização Terapêutica/métodos , Reparo do DNA , Proteínas de Ligação a DNA/sangue , Proteínas de Ligação a DNA/metabolismo , Endonucleases/sangue , Endonucleases/genética , Endonucleases/metabolismo , Feminino , Predisposição Genética para Doença , Testes Genéticos , Genótipo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Proteína 1 Complementadora Cruzada de Reparo de Raio-X , Proteína Grupo D do Xeroderma Pigmentoso/sangue , Proteína Grupo D do Xeroderma Pigmentoso/metabolismo
13.
Hell J Nucl Med ; 18(1): 2-4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25679071

RESUMO

Fluorine-18-labeled 2-fluoro-2-deoxy-D-glucose positron emission tomography/computerized tomography ((18)F-FDG PET/CT) plays an important role in detecting differentiated thyroid carcinoma (DTC) metastases with elevated thyroglobulin (Tg) and negative radioiodine ((131)I) uptake. In conclusion, (18)F-FDG PET/CT may fail to detect all DTC metastases, while (131)I WBS combined with (131)I SPET/CT may be a better cheaper and diagnostic tool as suggested by the case we presented here. Positive metastases in both (131)I and (18)F-FDG SPET/CT may indicate worse prognosis. Future research may add more evidence as to which is the best diagnostic imaging modality and relate it to the molecular mechanism of the uptake of the radionuclide used.


Assuntos
Fluordesoxiglucose F18 , Radioisótopos do Iodo , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundário , Masculino , Metástase Neoplásica , Prognóstico , Imagem Corporal Total
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