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1.
J Am Chem Soc ; 142(41): 17543-17556, 2020 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-32960592

RESUMEN

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.


Asunto(s)
Huesos/metabolismo , Nanoestructuras/química , Osteoclastos/metabolismo , Osteoporosis/prevención & control , Fosfatidiletanolaminas/química , Polietilenglicoles/química , Animales , Resorción Ósea/metabolismo , Dióxido de Carbono/química , Colesterol/química , Femenino , Humanos , Lecitinas/química , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Fosfatidiletanolaminas/metabolismo , Polietilenglicoles/metabolismo , Ligando RANK/metabolismo , Bicarbonato de Sodio/química , Propiedades de Superficie , Tetraciclina/química
2.
BMC Musculoskelet Disord ; 18(1): 378, 2017 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-28865444

RESUMEN

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.


Asunto(s)
Artroplastia de Reemplazo de Cadera/tendencias , Artroplastia de Reemplazo de Rodilla/tendencias , Pérdida de Sangre Quirúrgica/prevención & control , Transfusión de Sangre Autóloga/tendencias , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Transfusión Sanguínea/métodos , Transfusión Sanguínea/tendencias , Transfusión de Sangre Autóloga/métodos , Humanos , Trasplante Homólogo
3.
J Bone Joint Surg Am ; 98(18): 1578-85, 2016 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-27655986

RESUMEN

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.


Asunto(s)
Terapia por Acupuntura , Dolor Crónico/terapia , Osteoartritis de la Rodilla/terapia , Manejo del Dolor/métodos , Dolor Crónico/fisiopatología , Humanos , Osteoartritis de la Rodilla/fisiopatología , Dimensión del Dolor , Resultado del Tratamiento
4.
Biomaterials ; 81: 1-13, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26713680

RESUMEN

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.


Asunto(s)
Autofagia/efectos de los fármacos , Quitosano/química , Gelatina/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Microesferas , Osteoartritis/tratamiento farmacológico , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Animales , Cartílago/efectos de los fármacos , Cartílago/metabolismo , Cartílago/patología , Quitosano/síntesis química , Condrocitos/efectos de los fármacos , Condrocitos/patología , Reactivos de Enlaces Cruzados/química , Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Gelatina/síntesis química , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/síntesis química , Inyecciones Intraarticulares , Luz , Metacrilatos/síntesis química , Metacrilatos/química , Ratones Endogámicos C57BL , Proteínas Asociadas a Microtúbulos/metabolismo , Osteoartritis/patología , Extractos Vegetales/farmacología , Sinomenium/química , Sus scrofa
5.
J Immunol ; 173(6): 4207-17, 2004 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-15356172

RESUMEN

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.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Cisteína/metabolismo , Diterpenos/farmacología , Medicamentos Herbarios Chinos/farmacología , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Antiinflamatorios no Esteroideos/aislamiento & purificación , Unión Competitiva/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Línea Celular , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Diterpenos/aislamiento & purificación , Diterpenos/metabolismo , Evaluación Preclínica de Medicamentos , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/metabolismo , Selectina E/biosíntesis , Selectina E/metabolismo , Endotelio Vascular/citología , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/metabolismo , Inhibidores de Crecimiento/farmacología , Células HL-60 , Humanos , Hipersensibilidad/patología , Hipersensibilidad/prevención & control , Proteínas I-kappa B/antagonistas & inhibidores , Proteínas I-kappa B/metabolismo , Leucocitos/efectos de los fármacos , Leucocitos/metabolismo , Leucocitos/patología , Pulmón/efectos de los fármacos , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Inhibidor NF-kappaB alfa , FN-kappa B/genética , Subunidad p50 de NF-kappa B , Células 3T3 NIH , Infiltración Neutrófila/efectos de los fármacos , Sondas de Oligonucleótidos/antagonistas & inhibidores , Sondas de Oligonucleótidos/metabolismo , Oxidación-Reducción , Peritonitis/patología , Peritonitis/prevención & control , Unión Proteica/efectos de los fármacos , Choque Séptico/prevención & control , Factor de Transcripción ReIA
6.
Pharmazie ; 58(11): 833-5, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14664342

RESUMEN

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.


Asunto(s)
Asteraceae/química , Fenoles/química , Daño del ADN/efectos de los fármacos , Dimetilsulfóxido , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Rotación Óptica , Estrés Oxidativo/efectos de los fármacos , Fenoles/aislamiento & purificación , Extractos Vegetales/química , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
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