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1.
Biomedicines ; 11(10)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37893043

RESUMO

The dysregulated expression of cyclin genes can lead to the uncontrolled proliferation of cancer cells. Histone demethylase Jumonji-C domain-containing protein 5 (KDM8, JMJD5) and cyclin A1 (CCNA1) are pivotal in cell cycle progression. A promising candidate for augmenting cancer treatment is Allyl isothiocyanate (AITC), a natural dietary chemotherapeutic and epigenetic modulator. This study aimed to investigate AITC's impact on the KDM8/CCNA1 axis to elucidate its role in oral squamous cell carcinoma (OSCC) tumorigenesis. The expression of KDM8 and CCNA1 was assessed using a tissue microarray (TMA) immunohistochemistry (IHC) assay. In vitro experiments with OSCC cell lines and in vivo experiments with patient-derived tumor xenograft (PDTX) and SAS subcutaneous xenograft tumor models were conducted to explore AITC's effects on their expression and cell proliferation. The results showed elevated KDM8 and CCNA1 levels in the OSCC patient samples. AITC exhibited inhibitory effects on OSCC tumor growth in vitro and in vivo. Additionally, AITC downregulated KDM8 and CCNA1 expression while inducing histone H3K36me2 expression in oral cancer cells. These findings underscore AITC's remarkable anticancer properties against oral cancer, highlighting its potential as a therapeutic option for oral cancer treatment by disrupting the cell cycle by targeting the KDM8/CCNA1 axis.

2.
J Bone Miner Res ; 38(8): 1092-1103, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37254266

RESUMO

This systematic review and meta-analysis aimed to investigate the effect of nonalcoholic fatty liver disease (NAFLD) on bone mineral density (BMD) and the risk of osteoporosis and osteoporotic fracture in adults. We searched PubMed, MEDLINE, Embase, CINAHL, Web of Science, Cochrane Library, and Scopus for observational studies published from inception to January 2023 that reported adjusted effect sizes of NAFLD on BMD, osteopenia/osteoporosis, and osteoporotic fracture. The data were synthesized using multilevel and random-effects models. A total of 19 studies were included; of these, nine (21,294 participants) evaluated the effect of NAFLD on BMD, six (133,319 participants) investigated the risk of osteoporosis, and five (227,901 participants) assessed the risk of osteoporotic fracture. This meta-analysis showed that NAFLD was associated with decreased BMD (mean difference -0.019 g/cm2 , 95% confidence interval [CI] -0.036 to -0.002, I2 = 93%) and increased risks of osteoporosis (adjusted risk ratio [RR] = 1.28, 95% CI 1.08 to 1.52, I2 = 84%) and osteoporotic fractures (adjusted RR = 1.17, 95% CI 1.00 to 1.37, I2 = 67%). Subgroup analyses revealed that NAFLD had a significantly detrimental effect on BMD in men and on the BMD of the femoral neck and total hip. Stratified analyses by ethnicity demonstrated that NAFLD was not associated with BMD, osteoporosis, or osteoporotic fracture in non-Asian populations. The publication bias of all included studies was low; however, there was considerable heterogeneity among the studies, warranting a careful interpretation of the findings. Overall, our results suggest that NAFLD is associated with decreased BMD and an increased risk of osteoporosis or osteoporotic fractures. Male sex and the BMD of the femoral neck and total hip may be potential risk factors for decreased BMD in adults with NAFLD. Additionally, ethnic disparities were observed between Asian and non-Asian populations regarding BMD and osteoporotic fractures. © 2023 American Society for Bone and Mineral Research (ASBMR).


Assuntos
Hepatopatia Gordurosa não Alcoólica , Osteoporose , Fraturas por Osteoporose , Masculino , Humanos , Adulto , Fraturas por Osteoporose/complicações , Densidade Óssea , Hepatopatia Gordurosa não Alcoólica/complicações , Osteoporose/complicações , Osteoporose/epidemiologia , Colo do Fêmur
4.
BMC Musculoskelet Disord ; 22(1): 294, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33743671

RESUMO

BACKGROUND: The impact of associated chest wall injuries (CWI) on the complications of clavicle fracture repair is unclear to date. This study aimed to investigate the complications after surgical clavicle fracture fixation in patients with and without different degrees of associated CWI. METHODS: A retrospective review over a four-year period of patients who underwent clavicle fracture repair was conducted. A CWI and no-CWI group were distinguished, and the CWI group was subdivided into the minor-CWI (three or fewer rib fractures without flail chest) and complex-CWI (flail chest, four or more rib fractures) subgroup. Demographic data, classification of the clavicle fracture, number of rib fractures, and associated injuries were recorded. Overall complications included surgery-related complications and unplanned hospital readmissions. Univariate analysis and stepwise backward multivariate logistic regression were used to identify potential risk factors for complications. RESULTS: A total of 314 patients undergoing 316 clavicle fracture operations were studied; 28.7% of patients (90/314) occurred with associated CWI. Patients with associated CWI showed a significantly higher age, body mass index, and number of rib fractures. The overall and surgical-related complication rate were similar between groups. Unplanned 30-day hospital readmission rates were significantly higher in the complex-CWI group (p = 0.02). Complex CWI and number of rib fractures were both independent factor for 30-day unplanned hospital readmission (OR 1.59, 95% CI: 1.00-2.54 and OR 1.33, 95% CI: 1.06-1.68, respectively). CONCLUSION: CWI did not affect surgery-related complications after clavicle fracture repair. However, complex-CWI may increase 30-day unplanned hospital readmission rates.


Assuntos
Tórax Fundido , Traumatismos Torácicos , Parede Torácica , Clavícula/diagnóstico por imagem , Clavícula/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Humanos , Estudos Retrospectivos , Traumatismos Torácicos/epidemiologia , Traumatismos Torácicos/cirurgia , Parede Torácica/cirurgia
5.
ACS Nano ; 15(4): 7596-7607, 2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33760607

RESUMO

The exine capsules of pollen particles exhibit a variety of characteristic surface morphologies that promote their cell interactions; their use as antigen carriers for vaccination has been proposed. However, the allergy-causing substances in pollen particles may not all be removed, even by vigorous chemical treatments. To resolve this issue, this work develops systemic approaches for synthesizing pollen-mimetic metal-organic frameworks (MOFs), which comprise aluminum (Al) ions and an organic linker (2-aminoterephthalic acid), with tunable spike-like nanostructures on their surfaces. The as-synthesized MOFs act not only as a delivery vehicle that carries a model antigen (ovalbumin, OVA) but also as an adjuvant (Al). Scanning and transmission electron microscopies images reveal that the aspect ratio of the nanospikes that are grown on the MOFs can be controlled. A higher aspect ratio of the nanospikes on the MOFs is associated with greater cell attachment and faster and more efficient phagocytosis in cells, which results in greater expressions of pro-inflammatory cytokines. Consequently, a more robust immune response against the antigen of interest is elicited. These findings have broad implications for the rational design of the future antigen/adjuvant-presenting particles for vaccination.


Assuntos
Estruturas Metalorgânicas , Nanoestruturas , Comunicação Celular , Imunidade Humoral , Ovalbumina , Pólen
6.
Medicine (Baltimore) ; 99(32): e21611, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32769919

RESUMO

BACKGROUND: Low back pain (LBP) affects approximately 51% to 57% of hospital nurses and nurses' aides in Europe. New high-risk groups include home- and long-term-care nurses and physiotherapists. A number of European countries are experiencing a shortage of healthcare workers. Light therapy has been shown to be an effective treatment for various musculoskeletal disorders, including lateral epicondylitis, temporomandibular joint pain, carpal tunnel syndrome, and delayed-onset muscle soreness. A systematic review and meta-analysis demonstrated that low-level laser therapy is an effective method for relieving non-specific chronic low back pain (NSCLBP). However, the efficacy of light-emitting diode (LED) therapy for NSCLBP is disputed. This study aims to evaluate the effect of LED therapy on NSCLBP. METHODS AND ANALYSIS: We conducted a prospective, double-blind, randomized placebo-controlled trial of 148 patients with NSCLBP. The patients were randomly assigned to 2 groups: intervention group, where patients received LED photobiomodulation therapy 3 times a week for 2 weeks, and the sham group, where patients had sham therapy 3 times a week for 2 weeks. Primary outcome measures included the visual analog scale for pain, lumbar active range of motion assessments, and chair-rising times. Secondary outcome measures included a multidimensional fatigue inventory, fear-avoidance beliefs questionnaire, and the Oswestry disability index. The outcome measures were assessed before therapy and 2weeks, 4 weeks, 8 weeks, 12 weeks, and 6 months after the first interventions were completed. DISCUSSION: This study is a prospective, single-center, double-blind, randomized, controlled study. This study aims to research the efficacy of a 2-week LED program for NSCLBP working nurse. Our results will be useful for patients, working nurses, nurses' aides, and other healthcare workers with chronic low back pain. TRIAL REGISTRATION NUMBER: NCT04424823.


Assuntos
Protocolos Clínicos , Dor Lombar/terapia , Terapia com Luz de Baixa Intensidade/normas , Enfermeiras e Enfermeiros/estatística & dados numéricos , Adolescente , Adulto , Idoso , Dor Crônica/terapia , Método Duplo-Cego , Humanos , Terapia com Luz de Baixa Intensidade/instrumentação , Terapia com Luz de Baixa Intensidade/métodos , Pessoa de Meia-Idade , Manejo da Dor/métodos , Manejo da Dor/normas , Medição da Dor/métodos , Estudos Prospectivos , Inquéritos e Questionários , Escala Visual Analógica
7.
Biomaterials ; 230: 119629, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31767446

RESUMO

Most cancer vaccines under development are associated with defined tumor antigens rather than with all antigens of whole tumor cells, limiting the anti-tumor immune responses that they elicit. This work proposes an immunomodulator (R848)-loaded nanoparticle system (R848@NPs) that can absorb near-infrared light (+NIR) to cause low-temperature hyperthermia that interacts synergistically with its loaded R848 to relieve the tumor-mediated immunosuppressive microenvironment, generating robust anti-tumor memory immunity. In vitro results reveal that the R848@NPs could be effectively internalized by dendritic cells, causing their maturation and the subsequent regulation of their anti-tumor immune responses. Post-treatment observations in mice in which tumors were heat-treated at high temperatures reveal that tumor growth was significantly inhibited initially but not in the longer term, while low-temperature hyperthermia or immunotherapy alone simply delayed tumor growth. In contrast, a combined therapy that involved low-temperature hyperthermia and immunotherapy using R848@NPs/+NIR induced a long-lasting immunologic memory and consequently inhibited tumor growth and prevented cancer recurrence and metastasis. These results suggest that the method that is proposed herein is promising for generating cancer vaccines in situ, by using the tumor itself as the antigen source and the introduced R848@NPs/+NIR to generate a long-term anti-tumor immunity, for personalized immunotherapy.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Animais , Células Dendríticas , Hipertermia , Imunoterapia , Camundongos , Temperatura , Receptor 7 Toll-Like , Microambiente Tumoral , Vacinação
8.
Angew Chem Int Ed Engl ; 57(31): 9875-9879, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-29923670

RESUMO

Inflammation is involved in many human pathologies, including osteoarthritis (OA). Hydrogen (H2 ) is known to have anti-inflammatory effects; however, the bioavailability of directly administered H2 gas is typically poor. Herein, a local delivery system that can provide a high therapeutic concentration of gaseous H2 at inflamed tissues is proposed. The delivery system comprises poly(lactic-co-glycolic acid) microparticles that contain magnesium powder (Mg@PLGA MPs). Mg@PLGA MPs that are intra-muscularly injected close to the OA knee in a mouse model can act as an in situ depot that can evolve gaseous H2 continuously, mediated by the cycle of passivation/activation of Mg in body fluids, at a concentration that exceeds its therapeutic threshold. The analytical data that are obtained in the biochemical and histological studies indicate that the proposed Mg@PLGA MPs can effectively mitigate tissue inflammation and prevent cartilage from destruction, arresting the progression of OA changes.


Assuntos
Hidrogênio/química , Magnésio/uso terapêutico , Compostos Organometálicos/uso terapêutico , Osteoartrite/tratamento farmacológico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/uso terapêutico , Animais , Humanos , Magnésio/química , Camundongos , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Osteoartrite/metabolismo , Osteoartrite/patologia , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Células RAW 264.7 , Propriedades de Superfície
9.
J Am Chem Soc ; 139(37): 12923-12926, 2017 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-28870078

RESUMO

Hydrogen gas can reduce cytotoxic reactive oxygen species (ROS) that are produced in inflamed tissues. Inspired by natural photosynthesis, this work proposes a multicomponent nanoreactor (NR) that comprises chlorophyll a, l-ascorbic acid, and gold nanoparticles that are encapsulated in a liposomal (Lip) system that can produce H2 gas in situ upon photon absorption to mitigate inflammatory responses. Unlike a bulk system that contains free reacting molecules, this Lip NR system provides an optimal reaction environment, facilitating rapid activation of the photosynthesis of H2 gas, locally providing a high therapeutic concentration thereof. The photodriven NR system reduces the degrees of overproduction of ROS and pro-inflammatory cytokines both in vitro in RAW264.7 cells and in vivo in mice with paw inflammation that is induced by lipopolysaccharide (LPS). Histological examinations of tissue sections confirm the ability of the NR system to reduce LPS-induced inflammation. Experimental results indicate that the Lip NR system that can photosynthesize H2 gas has great potential for mitigating oxidative stress in tissue inflammation.


Assuntos
Ouro/metabolismo , Hidrogênio/metabolismo , Inflamação/metabolismo , Nanopartículas Metálicas/química , Estresse Oxidativo , Fotossíntese , Animais , Ouro/química , Hidrogênio/química , Inflamação/induzido quimicamente , Lipopolissacarídeos/metabolismo , Camundongos , Conformação Molecular , Células RAW 264.7
10.
J Orthop Surg Res ; 12(1): 131, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28915928

RESUMO

BACKGROUND: This meta-analysis compared clinical outcomes of arthroplasty vs. osteosynthesis for displaced femoral neck fractures. METHODS: Meta-analysis was performed on the difference in revision rate and overall mortality between participants undergoing osteosynthesis vs. total hip arthroplasty (THA), osteosynthesis vs. hemiarthroplasty (HA), or THA vs. HA. RESULTS: Pooled direct and indirect results indicated no significant difference in mortality between THA and HA (pooled OR = 0.87, 95% CI 0.55 to 1.38; P = 0.556), between THA and osteosynthesis (pooled OR = 1.17, 95% CI 0.69 to 1.99; P = 0.553), and between HA and osteosynthesis (pooled OR = 1.21, 95% CI 0.84 to 1.74; P = 0.304). Pooled direct and indirect results indicated no significant difference in revision rates between THA and HA (pooled OR = 0.90, 95% CI 0.26 to 3.19; P = 0.874). But, fewer revisions (OR = 0.19, 95% CI 0.10 to 0.34; P = 0.000) were seen in patients treated with THA than osteosynthesis and also in those treated with HA than osteosynthesis (OR = 0.12, 95% CI 0.07 to 0.20; P = 0.000). After excluding studies without showing normal cognition in inclusion criteria, pooled direct and indirect results also indicated no significant difference in mortality between THA, HA, and osteosynthesis. Similarly, there was no significant difference in revision rates between THA and HA, but HA and THA had significantly lower revision rates compared with osteosynthesis. CONCLUSIONS: There was no significant difference in overall mortality among osteosynthesis, HA, and THA. However, HA and THA had significantly lower revision rates compared with osteosynthesis. Results of the present study provide support for the use of hip arthroplasty to treat displaced fractures of the femoral neck.


Assuntos
Artroplastia de Quadril/mortalidade , Fraturas do Colo Femoral/cirurgia , Fixação Interna de Fraturas/mortalidade , Reoperação/estatística & dados numéricos , Fraturas do Colo Femoral/mortalidade , Humanos
11.
J Am Chem Soc ; 138(16): 5222-5, 2016 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-27075956

RESUMO

In the absence of adequate oxygen, cancer cells that are grown in hypoxic solid tumors resist treatment using antitumor drugs (such as doxorubicin, DOX), owing to their attenuated intracellular production of reactive oxygen species (ROS). Hyperbaric oxygen (HBO) therapy favorably improves oxygen transport to the hypoxic tumor tissues, thereby increasing the sensitivity of tumor cells to DOX. However, the use of HBO with DOX potentiates the ROS-mediated cytotoxicity of the drug toward normal tissues. In this work, we hypothesize that regional oxygen treatment by an implanted oxygen-generating depot may enhance the cytotoxicity of DOX against malignant tissues in a highly site-specific manner, without raising systemic oxygen levels. Upon implantation close to the tumor, the oxygen-generating depot reacts with the interstitial medium to produce oxygen in situ, effectively shrinking the hypoxic regions in the tumor tissues. Increasing the local availability of oxygen causes the cytotoxicity of DOX that is accumulated in the tumors to be significantly enhanced by the elevated production of ROS, ultimately allaying the hypoxia-induced DOX resistance in solid malignancies. Importantly, this enhancement of cytotoxicity is limited to the site of the tumors, and this feature of the system that is proposed herein is unique.


Assuntos
Antineoplásicos/farmacologia , Doxorrubicina/farmacologia , Implantes de Medicamento/farmacologia , Oxigenoterapia Hiperbárica/métodos , Hipóxia Tumoral/efeitos dos fármacos , Animais , Antígenos de Neoplasias/metabolismo , Cloreto de Cálcio/química , Anidrase Carbônica IX/metabolismo , Catalase/química , Catalase/metabolismo , Linhagem Celular Tumoral , Doxorrubicina/farmacocinética , Implantes de Medicamento/química , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Camundongos Nus , Oxigênio , Peróxidos/química , Tomografia por Emissão de Pósitrons , Ensaios Antitumorais Modelo de Xenoenxerto
12.
J Am Chem Soc ; 137(39): 12462-5, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26391111

RESUMO

Inflammation is associated with many diseases, in which activated inflammatory cells produce various reactive oxygen species (ROS), including H2O2. This work proposes an ultrasensitive ROS-responsive hollow microsphere (HM) carrier that contains an anti-inflammatory drug, an acid precursor consisting of ethanol and FeCl2, and sodium bicarbonate (SBC) as a bubble-generating agent. In cases of inflamed osteoarthritis, the H2O2 at low concentration diffuses through the HMs to oxidize their encapsulated ethanol in the presence of Fe(2+) by the Fenton reaction, establishing an acidic milieu. In acid, SBC decomposes to form CO2 bubbles, disrupting the shell wall of the HMs and releasing the anti-inflammatory drug to the problematic site, eventually protecting against joint destruction. These results reveal that the proposed HMs may uniquely exploit biologically relevant concentrations of H2O2 and thus be used for the site-specific delivery of therapeutics in inflamed tissues.


Assuntos
Anti-Inflamatórios/química , Preparações de Ação Retardada/química , Inflamação/tratamento farmacológico , Microesferas , Espécies Reativas de Oxigênio , Anti-Inflamatórios/farmacologia , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Gases/química , Limite de Detecção
13.
Cell Physiol Biochem ; 36(3): 1250-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26138885

RESUMO

BACKGROUND: Low concentrations of carbon monoxide (CO) have anti-inflammatory effects and can reduce bone erosion in a murine collagen-induced arthritis model. The objective of this study was to assess the effects of CO on receptor activator of NF-κB ligand (RANKL), one of the key stimulators of osteoclastogenesis. METHODS: The in vivo effects of CO on RANKL expression were assessed in a collagen antibody-induced arthritis model in mice. Cell proliferation and apoptosis were assessed in the RAW246.7 cell line stimulated with RANKL and exposed to either air or CO. The number of tartrate resistant acid phosphatase (TRAP)-positive RAW246.7 cells was also examined after treatment with RANKL and the peroxisome proliferator-activated receptor gamma (PPARγ) agonist, Troglitazone. RESULTS: CO reduced RANKL expression in the synovium of arthritic mice. Although CO slightly increased RAW246.7 cell proliferation, no differences in activated caspase 3 levels were detected. In addition, Troglitazone ameliorated the inhibitory effects of CO on RANKL-induced TRAP expression by RAW246.7 cells. CONCLUSIONS: CO suppresses osteoclast differentiation by inhibiting the RANKL-induced activation of PPAR-γ. Given the role of the PPAR-γ/cFos (AP-1) pathway in regulating the transcription factor, NFATc1, the master regulator of osteoclastogenesis, further studies are warranted to explore CO in treating inflammatory bone disorders.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antimetabólitos/farmacologia , Artrite Experimental/tratamento farmacológico , Monóxido de Carbono/farmacologia , Osteoclastos/efeitos dos fármacos , Ligante RANK/antagonistas & inibidores , Fosfatase Ácida/genética , Fosfatase Ácida/metabolismo , Administração por Inalação , Animais , Apoptose/efeitos dos fármacos , Artrite Experimental/genética , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Caspase 3/genética , Caspase 3/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cromanos/farmacologia , Regulação da Expressão Gênica , Isoenzimas/genética , Isoenzimas/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Osteoclastos/metabolismo , Osteoclastos/patologia , PPAR gama/antagonistas & inibidores , PPAR gama/genética , PPAR gama/metabolismo , Ligante RANK/farmacologia , Transdução de Sinais , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia , Fosfatase Ácida Resistente a Tartarato , Tiazolidinedionas/farmacologia , Troglitazona
14.
Angew Chem Int Ed Engl ; 54(34): 9890-3, 2015 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-26136242

RESUMO

Multidrug resistance (MDR) resulting from the overexpression of drug transporters such as P-glycoprotein (Pgp) increases the efflux of drugs and thereby limits the effectiveness of chemotherapy. To address this issue, this work develops an injectable hollow microsphere (HM) system that carries the anticancer agent irinotecan (CPT-11) and a NO-releasing donor (NONOate). Upon injection of this system into acidic tumor tissue, environmental protons infiltrate the shell of the HMs and react with their encapsulated NONOate to form NO bubbles that trigger localized drug release and serve as a Pgp-mediated MDR reversal agent. The site-specific drug release and the NO-reduced Pgp-mediated transport can cause the intracellular accumulation of the drug at a concentration that exceeds the cell-killing threshold, eventually inducing its antitumor activity. These results reveal that this pH-responsive HM carrier system provides a potentially effective method for treating cancers that develop MDR.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Camptotecina/análogos & derivados , Liberação Controlada de Fármacos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Óxido Nítrico/síntese química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/química , Camptotecina/química , Camptotecina/farmacologia , Feminino , Humanos , Concentração de Íons de Hidrogênio , Irinotecano , Células MCF-7 , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Nus , Óxido Nítrico/química
15.
Biomaterials ; 56: 26-35, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25934276

RESUMO

Repeated cancer treatments are common, owing to the aggressive and resistant nature of tumors. This work presents a chitosan (CS) derivative that contains self-doped polyaniline (PANI) side chains, capable of self-assembling to form micelles and then transforming into hydrogels driven by a local change in pH. Analysis results of small-angle X-ray scattering indicate that the sol-gel transition of this CS derivative may provide the mechanical integrity to maintain its spatial stability in the microenvironment of solid tumors. The micelles formed in the CS hydrogel function as nanoscaled heating sources upon exposure to near-infrared light, thereby enabling the selective killing of cancer cells in a light-treated area. Additionally, photothermal efficacy of the micellar hydrogel is evaluated using a tumor-bearing mouse model; hollow gold nanospheres (HGNs) are used for comparison. Given the ability of the micellar hydrogel to provide spatial stability within a solid tumor, which prevents its leakage from the injection site, the therapeutic efficacy of this hydrogel, as a photothermal therapeutic agent for repeated treatments, exceeds that of nanosized HGNs. Results of this study demonstrate that this in situ-formed micellar hydrogel is a highly promising modality for repeated cancer treatments, providing a clinically viable, minimally invasive phototherapeutic option for therapeutic treatment.


Assuntos
Quitosana/química , Hidrogéis/química , Raios Infravermelhos , Micelas , Neoplasias/terapia , Fototerapia/métodos , Animais , Linhagem Celular Tumoral , Quitosana/análogos & derivados , Humanos , Concentração de Íons de Hidrogênio , Luz , Nanopartículas Metálicas/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Camundongos Nus , Nanosferas/química , Transplante de Neoplasias , Transição de Fase , Fenilenodiaminas/química , Polímeros/química , Espalhamento de Radiação , Espectrofotometria Ultravioleta , Viscosidade
16.
J Control Release ; 199: 53-62, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25499553

RESUMO

Eradicating subcutaneous bacterial infections remains a significant challenge. This work reports an injectable system of hollow microspheres (HMs) that can rapidly produce localized heat activated by near-infrared (NIR) light and control the release of an antibiotic via a "molecular switch" in their polymer shells, as a combination strategy for treating subcutaneous abscesses. The HMs have a shell of poly(d,l-lactic-co-glycolic acid) (PLGA) and an aqueous core that is comprised of vancomycin (Van) and polypyrrole nanoparticles (PPy NPs), which are photothermal agents. Experimental results demonstrate that the micro-HMs ensure efficiently the spatial stabilization of their encapsulated Van and PPy NPs at the injection site in mice with subcutaneous abscesses. Without NIR irradiation, the HMs elute a negligible drug concentration, but release substantially more when exposed to NIR light, suggesting that this system is suitable as a photothermally-responsive drug delivery system. The combination of photothermally-induced hyperthermia and antibiotic therapy with HMs increases cytotoxicity for bacteria in abscesses, to an extent that is greater than the sum of the two treatments alone, demonstrating a synergistic effect. This treatment platform may find other clinical applications, especially for localized hyperthermia-based cancer therapy.


Assuntos
Abscesso/terapia , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Sistemas de Liberação de Medicamentos , Dermatopatias/terapia , Abscesso/tratamento farmacológico , Animais , Antibacterianos/farmacologia , Temperatura Alta , Raios Infravermelhos , Injeções Subcutâneas , Ácido Láctico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Microesferas , Nanopartículas , Fotoquímica , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Pirróis , Dermatopatias/tratamento farmacológico , Distribuição Tecidual , Vancomicina/administração & dosagem , Vancomicina/farmacologia , Vancomicina/uso terapêutico , Cicatrização/efeitos dos fármacos
17.
Small ; 10(20): 4100-5, 2014 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24976002

RESUMO

Treating inflammation with a dual-switch-controlled release system: The release of a drug from the developed microbead system occurs only in response to both an increase in local temperature and an acidic environmental pH. This dual-switch-controlled release system has the advantages of distinguishing between inflamed and healthy tissues to improve treatment efficacy.


Assuntos
Sistemas de Liberação de Medicamentos , Concentração de Íons de Hidrogênio , Microesferas , Microscopia Confocal , Microscopia Eletrônica de Varredura
18.
BMC Syst Biol ; 8: 57, 2014 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-24886323

RESUMO

BACKGROUND: During osteoclastogenesis, the maturation of osteoclast (OC) progenitors is stimulated by the receptor activator of nuclear factor-κB ligand (RANKL). Excess OC production plays a critical role in the pathogenesis of inflammatory bone disorders. Conversely, the inhibition of abnormal OC proliferation reduces inflammation-induced bone loss. Low concentrations of carbon monoxide (CO) are known to decrease inflammation and OC-mediated bone erosion but the molecular mechanism is unknown. RESULTS: To obtain insight into the biological function of CO, cultured RANKL-treated RAW 264.7 cells were used in an in vitro experimental model of osteoclastogenesis. The results showed that CO inhibited: 1) tartrate-resistant acid phosphatase (TRAP)-positive cell formation; 2) F-actin ring production; 3) c-fos pathway activation; 4) the expression of cathepsin K, TRAP, calcitonin receptor, and matrix metalloproteinase-9 mRNAs; 5) the expression of nuclear factor of activated T cells, cytoplasmic, calcineurin-dependent 1 in translation. Protein-protein interaction analysis predicted mitogen-activated protein kinase kinase kinase 4 as the controlling hub. CONCLUSIONS: Low-concentrations of CO (250 ppm) may inhibit osteoclastogenesis. Data from STRING- and IPA-based interactome analyses suggested that the expression of proteins with the functions of signal transduction, enzymes, and epigenetic regulation are significantly altered by CO during RANKL-induced osteoclastogenesis. Our study provides the first interactome analysis of osteoclastogenesis, the results of which supported the negative regulation of OC differentiation by CO.


Assuntos
Monóxido de Carbono/farmacologia , Diferenciação Celular/efeitos dos fármacos , Biologia Computacional , Macrófagos/citologia , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Ligante RANK/farmacologia , Actinas/biossíntese , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Camundongos , Osteoclastos/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos
19.
Adv Healthc Mater ; 3(11): 1854-61, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24789379

RESUMO

In the conventional treatment of osteomyelitis, the penetration of antibiotics into the infected bone is commonly poor. To ensure that the local antibiotic concentration is adequate, this work develops an injectable calcium phosphate (CP) cement in which is embedded pH-responsive hollow microspheres (HMs) that can control the release of a drug according to the local pH. The HMs are fabricated using a microfluidic device, with a shell of poly(D,L-lactic-co-glycolic acid) (PLGA) and an aqueous core that contains vancomycin (Van) and NaHCO3. At neutral pH, the CP/HM cement elutes a negligible concentration of the drug. In an acidic environment, the NaHCO3 that is encapsulated in the HMs reacts with the acid rapidly to generate CO2 bubbles, disrupting the PLGA shells and thereby releasing Van locally in excess of a therapeutic threshold. The feasibility of using this CP/HM cement to treat osteomyelitis is studied using a rabbit model. Analytical results reveal that the CP/HM cement provides highly effective local antibacterial activity. Histological examination further verifies the efficacy of the treatment by the CP/HM cement. The above findings suggest that the CP/HM cement is a highly efficient system for the local delivery of antibiotics in the treatment of osteomyelitis.


Assuntos
Cimentos Ósseos/química , Cimentos Ósseos/farmacologia , Dióxido de Carbono/química , Gases/química , Inflamação/tratamento farmacológico , Osteomielite/tratamento farmacológico , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Fosfatos de Cálcio/química , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Ácido Láctico/química , Microesferas , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Vancomicina/administração & dosagem , Vancomicina/química
20.
Planta Med ; 80(4): 255-61, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24510366

RESUMO

Advanced oral cancer has a poor prognosis because of the lack of an effective treatment. We explored the efficiency of combined treatment with triptolide and ionizing radiation for treating oral cancer. Human tongue cancer cells were treated with triptolide, ionizing radiation, or triptolide plus ionizing radiation. Cell proliferation, cell cycle arrest, and apoptotic influences were analyzed by FACS and immunohistochemistry. Tumor potency was examined in an in vivo human tongue cancer cells xenograft mouse model. Our results demonstrated that triptolide caused a marked reduction in colony number that was further enhanced with increasing doses of ionizing radiation. Triptolide increased apoptosis and decreased the expression of anti-apoptotic proteins. In vivo, combination treatment synergistically reduced tumor weight and volume possibly via the induction of apoptosis and reduction in anti-apoptotic protein expression. In conclusion, triptolide plus ionizing radiation treatment had synergistic anti-tumor effects, especially in vivo, and may be a promising combined modality therapy for advanced oral cancer.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Diterpenos/uso terapêutico , Fenantrenos/uso terapêutico , Fitoterapia , Neoplasias da Língua/tratamento farmacológico , Tripterygium/química , Animais , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/radioterapia , Linhagem Celular Tumoral , Quimioterapia Adjuvante , Diterpenos/farmacologia , Compostos de Epóxi/farmacologia , Compostos de Epóxi/uso terapêutico , Humanos , Camundongos , Fenantrenos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Língua/efeitos dos fármacos , Neoplasias da Língua/radioterapia , Ensaios Antitumorais Modelo de Xenoenxerto
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