Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
J Am Chem Soc ; 142(41): 17543-17556, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-32960592

RESUMO

Osteoporosis is a global chronic disease characterized by severe bone loss and high susceptibility to fragile fracture. It is widely accepted that the origin acidified microenvironment created by excessive osteoclasts causes irreversible bone mineral dissolution and organic degradation during osteoclastic resorption. However, current clinically available approaches are mainly developed from the perspective of osteoclast biology rather than the critical acidified niche. Here, we developed a smart "nanosacrificial layer" consisting of sodium bicarbonate (NaHCO3)-containing and tetracycline-functionalized nanoliposomes (NaHCO3-TNLs) that can target bone surfaces and respond to external secreted acidification from osteoclasts, preventing osteoporosis. In vitro and in vivo results prove that this nanosacrificial layer precisely inhibits the initial acidification of osteoclasts and initiates a chemically regulated biocascade to remodel the bone microenvironment and realize bone protection: extracellular acid-base neutralization first inhibits osteoclast function and also promotes its apoptosis, in which the apoptosis-derived extracellular vesicles containing RANK (receptor activator of nuclear factor-κ B) further consume RANKL (RANK ligand) in serum, achieving comprehensive osteoclast inhibition. Our therapeutic strategy for osteoporosis is based on original and precise acid-base neutralization, aiming to reestablish bone homeostasis by using a smart nanosacrificial layer that is able to induce chemically regulated biocascade effects. This study also provides a novel understanding of osteoporosis therapy in biomedicine and clinical treatments.


Assuntos
Osso e Ossos/metabolismo , Nanoestruturas/química , Osteoclastos/metabolismo , Osteoporose/prevenção & controle , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Animais , Reabsorção Óssea/metabolismo , Dióxido de Carbono/química , Colesterol/química , Feminino , Humanos , Lecitinas/química , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Fosfatidiletanolaminas/metabolismo , Polietilenoglicóis/metabolismo , Ligante RANK/metabolismo , Bicarbonato de Sódio/química , Propriedades de Superfície , Tetraciclina/química
2.
BMC Musculoskelet Disord ; 18(1): 378, 2017 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-28865444

RESUMO

BACKGROUND: Total joint arthroplasty is associated with significant blood loss and often requires blood transfusion. However, allogeneic blood transfusion (ABT) may lead to severe problems, such as immunoreaction and infection. Postoperative autotransfusion, an alternative to ABT, is controversial. We conducted a meta-analysis to evaluate the ability of postoperative autotransfusion to reduce the need for ABT following total knee arthroplasty (TKA) and total hip arthroplasty (THA). METHODS: Systematic literature searches for randomized controlled trials were performed using PubMed, Embase, and the Cochrane Library until February 2016. Relative risks (RRs) and weighted mean differences with 95% confidence intervals (CIs) were calculated using fixed-effect or random-effect models; we also evaluated publication bias and heterogeneity. RESULTS: Seventeen trials with a total of 2314 patients were included in the meta-analysis. The pooled RRs of ABT rate between autotransfusion and the regular drainage/no drainage groups for TKA and THA were 0.446 (95% CI = 0.287, 0.693; p < 0.001) and 0.757 (95% CI = 0.599, 0.958; p = 0.020), respectively. In the subgroup analysis performed in TKA patients according to control interventions, the pooled RRs were 0.377 (95% CI = 0.224, 0.634; p < 0.001) (compared with regular drainage) and 0.804 (95% CI = 0.453, 1.426, p = 0.456) (compared with no drainage). In the subgroup analysis performed for THA, the pooled RRs were 0.536 (95% CI = 0.379, 0.757, p < 0.001) (compared with regular drainage) and 1.020 (95% CI = 0.740, 1.405, p = 0.904) (compared with no drainage). CONCLUSIONS: Compared to regular drainage, autotransfusion reduces the need for ABT following TKA and THA. This reduction is not present when comparing autotransfusion to no drainage. However, the reliability of the meta-analytic results concerning TKA was limited by significant heterogeneity in methods among the included studies.


Assuntos
Artroplastia de Quadril/tendências , Artroplastia do Joelho/tendências , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue Autóloga/tendências , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Transfusão de Sangue/métodos , Transfusão de Sangue/tendências , Transfusão de Sangue Autóloga/métodos , Humanos , Transplante Homólogo
3.
J Bone Joint Surg Am ; 98(18): 1578-85, 2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-27655986

RESUMO

BACKGROUND: Acupuncture reportedly relieves chronic knee pain and improves physical function in patients diagnosed with osteoarthritis, but the duration of these effects is controversial. The aim of this study was to evaluate the temporal effects of acupuncture on chronic knee pain due to knee osteoarthritis by means of a meta-analysis. METHODS: The PubMed, Embase, and Cochrane Central Register of Controlled Trials databases were searched for studies published through March 2015. Ten randomized controlled trials of acupuncture compared with sham acupuncture, usual care, or no intervention for chronic knee pain in patients with clinically diagnosed or radiographically confirmed knee osteoarthritis were included. All of the studies were available in English. Weighted mean differences (WMDs), 95% confidence intervals (CIs), publication bias, and heterogeneity were calculated. RESULTS: The acupuncture groups showed superior pain improvement (p < 0.001; WMD = -1.24 [95% CI, -1.92 to -0.56]; I(2) > 50%) and physical function (p < 0.001; WMD = 4.61 [95% CI, 2.24 to 6.97]; I(2) > 50%) in the short term (up to 13 weeks). The acupuncture groups showed superior physical function (p = 0.016; WMD = 2.73 [95% CI, 0.51 to 4.94]; I(2) > 50%) but not superior pain improvement (p = 0.199; WMD = -0.55 [95% CI, -1.39 to 0.29]; I(2) > 50%) in the long term (up to 26 weeks). Subgroup analysis revealed that the acupuncture groups tended to have better outcomes compared with the controls. Significant publication bias was not detected (p > 0.05), but the heterogeneity of the studies was substantial. CONCLUSIONS: This meta-analysis demonstrates that acupuncture can improve short and long-term physical function, but it appears to provide only short-term pain relief in patients with chronic knee pain due to osteoarthritis. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Terapia por Acupuntura , Dor Crônica/terapia , Osteoartrite do Joelho/terapia , Manejo da Dor/métodos , Dor Crônica/fisiopatologia , Humanos , Osteoartrite do Joelho/fisiopatologia , Medição da Dor , Resultado do Tratamento
4.
Biomaterials ; 81: 1-13, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26713680

RESUMO

Reduced expression of autophagy regulators has been observed in pathological cartilage in humans and mice. The present study aimed to investigate the synergistic therapeutic effect of promotion of chondrocyte autophagy via exposure to sinomenium (SIN) encapsulated by chitosan microspheres (CM-SIN) and photo-crosslinked gelatin methacrylate (GelMA) hydrogel, with the goal of evaluating CM-SIN as a treatment for patients with osteoarthritis. First, we fabricated and characterized GelMA hydrogels and chitosan microspheres. Next, we measured the effect of SIN on cartilage matrix degradation induced by IL1-ß in chondrocytes and an ex vivo model. SIN ameliorated the pathological changes induced by IL1-ß at least partially through activation of autophagy. Moreover, we surgically induced osteoarthritis in mice, which were injected intra-articularly with CM-SIN and GelMA. Cartilage matrix degradation and chondrocyte autophagy were evaluated 4 and 8 weeks after surgery. Treatment with the combination of CM-SIN and GelMA retarded the progression of surgically induced OA. SIN ameliorated cartilage matrix degradation at least partially by inducing autophagy in vivo. Our results demonstrate that injection of the combination of GelMA hydrogel and CM-SIN could be a promising strategy for treating patients with osteoarthritis.


Assuntos
Autofagia/efeitos dos fármacos , Quitosana/química , Gelatina/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Microesferas , Osteoartrite/tratamento farmacológico , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Animais , Cartilagem/efeitos dos fármacos , Cartilagem/metabolismo , Cartilagem/patologia , Quitosana/síntese química , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Reagentes de Ligações Cruzadas/química , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Gelatina/síntese química , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntese química , Injeções Intra-Articulares , Luz , Metacrilatos/síntese química , Metacrilatos/química , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Osteoartrite/patologia , Extratos Vegetais/farmacologia , Sinomenium/química , Sus scrofa
5.
J Immunol ; 173(6): 4207-17, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15356172

RESUMO

NF-kappaB is a central transcriptional factor and a pleiotropic regulator of many genes involved in immunological responses. During the screening of a plant extract library of traditional Chinese herbal medicines, we found that NF-kappaB activity was potently inhibited by andrographolide (Andro), an abundant component of the plant Andrographis that has been commonly used as a folk remedy for alleviation of inflammatory disorders in Asia for millennia. Mechanistically, it formed a covalent adduct with reduced cysteine (62) of p50, thus blocking the binding of NF-kappaB oligonucleotide to nuclear proteins. Andro suppressed the activation of NF-kappaB in stimulated endothelial cells, which reduced the expression of cell adhesion molecule E-selectin and prevented E-selectin-mediated leukocyte adhesion under flow. It also abrogated the cytokine- and endotoxin-induced peritoneal deposition of neutrophils, attenuated septic shock, and prevented allergic lung inflammation in vivo. Notably, it had no suppressive effect on IkappaBalpha degradation, p50 and p65 nuclear translocation, or cell growth rates. Our results thus reveal a unique pharmacological mechanism of Andro's protective anti-inflammatory actions.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Cisteína/metabolismo , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Ligação Competitiva/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Diterpenos/isolamento & purificação , Diterpenos/metabolismo , Avaliação Pré-Clínica de Medicamentos , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/metabolismo , Selectina E/biossíntese , Selectina E/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Inibidores do Crescimento/farmacologia , Células HL-60 , Humanos , Hipersensibilidade/patologia , Hipersensibilidade/prevenção & controle , Proteínas I-kappa B/antagonistas & inibidores , Proteínas I-kappa B/metabolismo , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Leucócitos/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Inibidor de NF-kappaB alfa , NF-kappa B/genética , Subunidade p50 de NF-kappa B , Células NIH 3T3 , Infiltração de Neutrófilos/efeitos dos fármacos , Sondas de Oligonucleotídeos/antagonistas & inibidores , Sondas de Oligonucleotídeos/metabolismo , Oxirredução , Peritonite/patologia , Peritonite/prevenção & controle , Ligação Proteica/efeitos dos fármacos , Choque Séptico/prevenção & controle , Fator de Transcrição RelA
6.
Pharmazie ; 58(11): 833-5, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14664342

RESUMO

From the ethanolic extract of the whole plant of Anaphalis aureo-punctata, a new acylated flavonoid glycoside 3-O-kaempferol-3-O-acetyl-6-O-(p-coumaroyl)-beta-D-glucopyranoside (1), and five known phenolic compounds were isolated. Their structures were established by spectral methods (UV, IR, MS, 1D, 2D-NMR). The flavonoid glycosides, 1, 2 and 3 showed markedly inhibited oxidative DNA strand breaks induced by Fenton reaction and NADH/PMS in a concentration-dependent manner.


Assuntos
Asteraceae/química , Fenóis/química , Dano ao DNA/efeitos dos fármacos , Dimetil Sulfóxido , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Rotação Ocular , Estresse Oxidativo/efeitos dos fármacos , Fenóis/isolamento & purificação , Extratos Vegetais/química , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA