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1.
J Musculoskelet Neuronal Interact ; 13(4): 442-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24292614

RESUMO

Exogenous stimulation of skeletal muscle or tendon is often used to improve range of motion. Despite substantial research efforts, however, the effects of vibration on flexibility have not been clarified. In this review, we investigated the effects of acute and chronic intervention programs which used vibration to improve flexibility in young healthy individuals. Effect size was calculated using data from a total of 600 participants in 19 studies before and after the introduction of vibration-based intervention, and a total of 324 participants in 13 studies on the additive effects of vibration compared with the identical conditions without vibration. Sub-group analyses were performed based on intervention period, type of exercise, and type of vibration. Meta-analysis showed that vibration interventions had significant effects on flexibility (standardized mean difference [SMD]=-0.79, 95% confidence interval [CI]=-1.14- -0.43; p<0.001), albeit with the possibility of heterogeneity (I(2)=75%). Another meta-analysis revealed a significant additive effect of vibration on flexibility compared with the identical condition without vibration (SMD=0.25, 95%CI=0.03-0.48; P=0.03), with small heterogeneity (I(2)=0%). The risk of publication bias was low judged from Kendall's τ statistic. We concluded that the use of vibration might lead to additive improvements in flexibility.


Assuntos
Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Amplitude de Movimento Articular/fisiologia , Vibração , Adulto , Humanos
2.
J Musculoskelet Neuronal Interact ; 13(3): 380-90, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23989260

RESUMO

Exercise with whole-body vibration (WBV) is becoming popular as an alternative to conventional training or as supplementary training. However, despite increasing research efforts in this field, additive effects of WBV on muscle performance remain unclarified. In this review, we investigated the additive effects of long-term WBV on muscle strength and power. This meta-analysis was restricted to randomized controlled trials lasting for at least 5 weeks comparing exercise with and without WBV, or comparing only WBV exposure and control. Data from a total of 314 participants in 10 studies on knee extension muscle strength, and 249 participants in 7 studies on countermovement jump height were pooled using random-effect models. Meta-analysis showed significant additional effects of WBV on muscle strength (standardized mean difference [SMD]=0.76, 95% confidence interval [CI]=0.21-1.32; p=0.007) and countermovement jump (SMD=0.87, 95% CI=0.29-1.46; p=0.003). Based on these findings, we concluded that the use of WBV would lead to greater improvements in both knee extension muscle strength and countermovement jump than under identical conditions without WBV.


Assuntos
Exercício Físico/fisiologia , Força Muscular/fisiologia , Vibração , Humanos , Músculo Esquelético/fisiologia
3.
Scand J Med Sci Sports ; 23(1): 84-95, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21812821

RESUMO

The effects of resistance training (RT) combined with whole-body vibration (WBV) on muscle fitness, particularly muscle hypertrophy and neuromuscular performance, are not well understood. We investigated the effects of WBV in healthy, untrained participants after a 13-week RT course by performing magnetic resonance imaging and by measuring maximal isometric (with electromyography) and isokinetic knee extension strengths, isometric lumbar extension torque, countermovement-jump, knee extension endurance, and sit-ups. Thirty-two individuals (22-49 years old) were randomly assigned to RT groups with (RT-WBV, n=16) or without WBV (RT, n=16). Following the RT course, significantly higher increases in the cross-sectional areas of m. psoas major (vs baseline values) and erector spinae muscle (vs the RT group) were observed in the RT-WBV group (+10.7%, P<0.05; +8.7%, P<0.05) compared with the RT group (+3.8%, P=0.045; 0.0%). Higher increases from baseline were also observed in maximal isometric force, concentric knee extension torque, countermovement-jump, and maximal isometric lumbar extension torque in RT-WBV (+63.5%; +76.7%, +15.0%, and +51.5%, respectively; P<0.05) than in those of RT (+25.6%, P=0.001; +17.8%, P=0.18; +11.3%, P=0.001; and +26.4%, P<0.001, respectively). The WBV-induced increases in muscle hypertrophy and isometric lumbar extension torque suggest a potential benefit of incorporating WBV into slow-velocity RT programs involving exercises of long duration.


Assuntos
Força Muscular/fisiologia , Aptidão Física/fisiologia , Treinamento Resistido/métodos , Vibração , Músculos Abdominais/fisiologia , Adulto , Análise de Variância , Antropometria , Eletromiografia , Ingestão de Energia/fisiologia , Feminino , Humanos , Contração Isométrica/fisiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Torque , Adulto Jovem
4.
Clin Exp Immunol ; 169(1): 1-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22670772

RESUMO

Co-stimulatory molecules are important for regulating T cell activation and immune response. CD274 [programmed death ligand 1 (PD-L1), B7-H1] has emerged as an important immune modulator that can block T cell receptor signalling. We have investigated whether PD-L1 and other co-stimulatory ligands could be expressed in human B cells stimulated by cytosine-phosphate-guanosine (CpG)-DNA. CpG-DNA strongly induced the co-inhibitory molecule ligand, PD-L1, of human B cells. Results show that nuclear factor-kappa B (NF-κB) signalling is involved directly in CpG-DNA-induced PD-L1 expression in human B cells. We sought to determine the effect of CpG-DNA-treated B cells on T helper type 2 (Th2) cytokine production in Cry j 1 (Japanese pollen antigen)-stimulated human CD4-positive cells from patients with seasonal allergic rhinitis caused by Japanese cedar pollen. CpG-DNA-treated B cells reduced Cry j 1-induced interleukin (IL)-5 and IL-13 production in CD4-positive cells. When the binding of PD-1 to PD-L1 was inhibited by PD-1-immunoglobulin (Ig), this chimera molecule reversed the previously described reductions in IL-5 and IL-13 production. In contrast, the CpG B-treated B cells increased both interferon (IFN)-γ and IL-12 production in the presence of Cry j 1-stimulated CD4-positive cells. CpG-DNA simultaneously reduced the expression of B7RP-1 [also known as inducible co-stimulator ligand (ICOSL), B7-H2] and the ligand of CD30 (CD30L). These results indicate that CpG-DNA induces co-inhibitory molecule ligand PD-L1 expression in human B cells and PD-L1 can suppress Th2 cytokine production in Cry j 1-stimulated CD4-positive cells, while CpG-DNA increased Th1 cytokine production and reduced the expression of co-stimulatory molecule ligands that can promote Th2 inflammatory responses.


Assuntos
Linfócitos B/imunologia , Antígeno B7-H1/imunologia , Citocinas/biossíntese , Oligodesoxirribonucleotídeos/imunologia , Pólen/imunologia , Células Th2/imunologia , Adjuvantes Imunológicos/farmacologia , Antígenos de Plantas/imunologia , Linfócitos B/efeitos dos fármacos , Comunicação Celular/imunologia , Células Cultivadas , Citocinas/imunologia , Humanos , Ligante Coestimulador de Linfócitos T Induzíveis/imunologia , Interferon gama/imunologia , Interleucina-12/imunologia , Interleucina-13/imunologia , Interleucina-5/imunologia , Ativação Linfocitária/imunologia , Subunidade p50 de NF-kappa B/imunologia , Oligodesoxirribonucleotídeos/farmacologia , Proteínas de Plantas/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Rinite Alérgica Sazonal/imunologia
5.
Int J Oral Maxillofac Surg ; 51(8): 992-999, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34551875

RESUMO

The EuroQol 5-dimension 5-level (EQ-5D-5L) instrument is among the most used preference-based quality of life (QOL) measures for cost-utility analysis. Each dimension is evaluated on five levels. The aim of this study was to clarify whether the EQ-5D-5L, which consists of only five items, correlates with profile-based QOL measures in Japanese oral cancer patients during the perioperative period. One hundred participants with oral cancer undergoing radical therapy completed QOL assessments before treatment, at treatment completion, and 1 and 3 months after treatment using the EQ-5D-5L and Functional Assessment of Cancer Therapy - Head & Neck instrument (FACT-H&N, Japanese version). To clarify how the EQ-5D-5L reflects the FACT-H&N, multiple regression analyses were performed using FACT-H&N subscales. The ceiling effect of the EQ-5D-5L was investigated. The EQ-5D-5L moderately correlated with the FACT-H&N over the entire perioperative period (rs = 0.586, P < 0.01). In the multiple regression analysis, the EQ-5D-5L was strongly reflected in the physical wellbeing subscale of the FACT-H&N, excluding social wellbeing. The pre-treatment EQ-5D-5L score was decreased owing to the impacts of the dimensions of pain/discomfort and anxiety/depression. The EQ-5D-5L did not have a ceiling effect in oral cancer patients. The EQ-5D-5L appears to generally correlate with the FACT-H&N for oral cancer patients during the perioperative period.


Assuntos
Neoplasias Bucais , Qualidade de Vida , Humanos , Japão , Neoplasias Bucais/cirurgia , Período Perioperatório , Psicometria/métodos , Inquéritos e Questionários
6.
Heliyon ; 8(11): e11468, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36406717

RESUMO

Background: We previously reported a novel technique for fabricating dermo-epidermal junction (DEJ)-like micropatterned collagen scaffolds to manufacture an ex vivo produced oral mucosa equivalent (EVPOME) for clinical translation; however, more biomimetic micropatterns are required to promote oral keratinocyte-based tissue engineering/regenerative medicine. In addition, in-process monitoring for quality control of tissue-engineered products is key to successful clinical outcomes. However, evaluating three-dimensional tissue-engineered constructs such as EVPOME is challenging. This study aimed to update our technique to fabricate a more biomimetic DEJ structure of oral mucosa and to investigate the efficacy of optical coherence tomography (OCT) in combination with deep learning for non-invasive EVPOME monitoring. Methods: A picosecond laser-textured microstructure mimicking DEJ on stainless steel was used as a negative mould to fabricate the micropatterned collagen scaffold. During EVPOME manufacturing, OCT was applied twice to monitor the EVPOME and evaluate its epithelial thickness. Findings: Our moulding system resulted in successful micropattern replication on the curved collagen scaffold. OCT imaging visualised the epithelial layer and the underlying micropatterned scaffold in EVPOME, enabling to non-invasively detect specific defects not found before the histological examination. Additionally, a gradual increase in epithelial thickness was observed over time. Conclusion: These findings demonstrate the feasibility of using a stainless-steel negative mould to create a more biomimetic micropattern on collagen scaffolds and the potential of OCT imaging for quality control in oral keratinocyte-based tissue engineering/regenerative medicine.

7.
J Viral Hepat ; 16(7): 524-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19215576

RESUMO

In this study, 520 serum samples from Yezo-deer in the Hidaka district, Hokkaido, Japan were examined by enzyme-linked immunosorbent assay to investigate whether the animals were infected with hepatitis E virus (HEV). The distribution of optical density values showed a bimodal pattern and 181 samples (34.8%) were deemed to be antibody-positive against HEV. At least five (2.8%) of the positive sera gave specific bands by Western blot analysis. An age-dependent increase in prevalence of the antibodies was found among the animals. These findings indicate that Yezo-deer are a possible host for HEV infection. To avoid the risk of becoming HEV infected, the consumption of raw Yezo-deer meat must be prohibited.


Assuntos
Cervos , Anticorpos Anti-Hepatite/sangue , Vírus da Hepatite E/imunologia , Hepatite E/veterinária , Fatores Etários , Animais , Western Blotting/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Hepatite E/epidemiologia , Japão , Masculino , Prevalência , Testes Sorológicos
8.
Science ; 215(4537): 1249-51, 1982 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-7058343

RESUMO

Norethisterone (17 alpha-ethynyl-19-nortestosterone) is an effective irreversible inhibitor of estrogen synthetase (aromatase), the enzyme responsible for the conversion of androgens to estrogens, even at a 2 X 10(-6) molar concentration. This irreversible inactivation, which is directed toward the active site of aromatase and requires the cofactor-reduced nicotinamide adenine dinucleotide phosphate, is both time- and concentration-dependent. Ethisterone (17 alpha-ethynyltestosterone), in contrast, is not a suicide inhibitor of aromatase even at concentrations of 10(-4) molar.


Assuntos
Inibidores da Aromatase , Anticoncepcionais Orais/farmacologia , Estrogênios/biossíntese , Noretindrona/farmacologia , Oxirredutases/antagonistas & inibidores , Sítios de Ligação/efeitos dos fármacos , Feminino , Humanos , Cinética , Microssomos/enzimologia , Placenta/enzimologia , Gravidez
9.
Clin Exp Allergy ; 38(12): 1875-81, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19037964

RESUMO

BACKGROUND: IL-33, an IL-1-like cytokine, is a ligand for IL1RL1, which is an important effector molecule of type 2 T helper responses. Although IL-33/IL1RL1 interaction has been suggested to be important in induction of allergic airway inflammation, serum levels of IL-33 and the genetic influences of the polymorphisms of IL-33 in human allergic diseases are unclear. OBJECTIVE: The aim of this study was to examine whether the serum IL-33 level and polymorphisms in IL-33 are associated with Japanese cedar (JC) pollinosis, the most common form of allergic rhinitis, and a major public health problem, in Japan. METHODS: We performed linkage disequilibrium (LD) mapping of the gene using the HapMap database, and two selected tag single nucleotide polymorphisms were genotyped. We conducted an association study of IL-33 (JC pollinosis, n=170; normal controls, n=100) and measured the IL-33 levels in sera of the 270 subjects by ELISA. RESULTS: Serum levels of IL-33 were significantly higher in patients with JC pollinosis (P=0.0018) than in controls. In genetic association analysis, we found a positive association between the polymorphism and JC pollinosis (P=0.048). CONCLUSION: Our results support a role for IL-33 in the pathogenesis of JC pollinosis.


Assuntos
Alérgenos/efeitos adversos , Cryptomeria/imunologia , Interleucinas/sangue , Interleucinas/genética , Pólen/efeitos adversos , Rinite Alérgica Sazonal/imunologia , Adulto , Suscetibilidade a Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina E/sangue , Interleucina-33 , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Rinite Alérgica Sazonal/sangue , Rinite Alérgica Sazonal/genética , Adulto Jovem
10.
J Steroid Biochem Mol Biol ; 178: 159-166, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29229304

RESUMO

Cytochrome P450 17A1 (CYP17A1) is a dual-function enzyme catalyzing reactions necessary for cortisol and androgen biosynthesis. CYP17A1 is a validated drug target for prostate cancer as CYP17A1 inhibition significantly reduces circulating androgens and improves survival in castration-resistant prostate cancer. Germline CYP17A1 genetic variants with altered CYP17A1 activity manifesting as various endocrinopathies are extremely rare; however, characterizing these variants provides critical insights into CYP17A1 protein structure and function. By querying the dbSNP online database and publically available data from the 1000 genomes project (http://browser.1000genomes.org), we identified two CYP17A1 nonsynonymous genetic variants with unknown consequences for enzymatic activity and stability. We hypothesized that the resultant amino acid changes would alter CYP17A1 stability or activity. To test this hypothesis, we utilized a HEK-293T cell-based expression system to characterize the functional consequences of two CYP17A1 variants, D216H (rs200063521) and G162R (rs141821705). Cells transiently expressing the D216H variant demonstrate a selective impairment of 16α-hydroxyprogesterone synthesis by 2.1-fold compared to wild-type (WT) CYP17A1, while no effect on 17α-hydroxyprogesterone synthesis was observed. These data suggest that substrate orientations in the active site might be altered with this amino acid substitution. In contrast, the G162R substitution exhibits decreased CYP17A1 protein stability compared to WT with a near 70% reduction in protein levels as determined by immunoblot analysis. This variant is preferentially ubiquitinated and degraded prematurely, with an enzyme half-life calculated to be ∼2.5 h, and proteasome inhibitor treatment recovers G162R protein expression to WT levels. Together, these data provide new insights into CYP17A1 structure-function and stability mechanisms.


Assuntos
Oxigenases de Função Mista/metabolismo , Mutação , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 17-alfa-Hidroxilase/metabolismo , Domínio Catalítico , Células HEK293 , Meia-Vida , Humanos , Conformação Proteica , Esteroide 17-alfa-Hidroxilase/química , Ubiquitinação
11.
Leukemia ; 32(12): 2729-2730, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30232464

RESUMO

Owing to the insufficient specificity of the anti-myeloproliferative leukemia protein (MPL) antibody in the original version of this Article, Figure 6 and parts of Figures 2a, 4e, and 5a do not represent the correct information. The corrected version of Figure 6 is in this correction and those of Figures 2a, 4e, and 5a are shown in the supplemental information.

12.
Bone Joint J ; 99-B(2): 175-183, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28148658

RESUMO

AIMS: Transtrochanteric rotational osteotomy (TRO) is performed for young patients with non-traumatic osteonecrosis of the femoral head (ONFH) to preserve the hip. We aimed to investigate the long-term outcomes and the risk factors for failure 15 years after this procedure. PATIENTS AND METHODS: This study included 95 patients (111 hips) with a mean age of 40 years (21 to 64) who underwent TRO for ONFH. The mean follow-up was 18.2 years (3 to 26). Kaplan-Meier survivorship analyses were performed with conversion to total hip arthroplasty (THA) and radiological failure due to secondary collapse of the femoral head or osteoarthritic changes as the endpoint. Multivariate analyses were performed to assess risk factors for each outcome. RESULTS: Survival rates at 15 years with conversion to THA and radiological failure as the endpoint were 59% (95% confidence interval (CI) 49 to 67) and 30% (95% CI 22 to 39), respectively. Necrotic type C2 ONFH (lesions extending laterally to the acetabular edge) (hazards ratio (HR) 3.9) and age > 40 years (HR 2.5) were risk factors for conversion to THA. Stage > 3a ONFH (HR 2.0) and age > 40 years (HR 1.9) were risk factors for radiological failure. CONCLUSION: The 15 year outcomes after TRO for ONFH are unfavorable because osteoarthritic changes occur after five years post-operatively. Cite this article: Bone Joint J 2017;99-B:175-83.


Assuntos
Necrose da Cabeça do Fêmur/cirurgia , Osteotomia/métodos , Adulto , Feminino , Fêmur/cirurgia , Necrose da Cabeça do Fêmur/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/etiologia , Estudos Retrospectivos , Rotação , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
13.
Leukemia ; 31(12): 2709-2716, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28386106

RESUMO

Myelofibrosis (MF) may be caused by various pathogenic mechanisms such as elevation in circulating cytokine levels, cellular interactions and genetic mutations. However, the underlying mechanism of MF still remains unknown. Recent studies have revealed that fibrocytes, the spindle-shaped fibroblast-like hematopoietic cells, and the thrombopoietin (TPO)/myeloproliferative leukemia protein (MPL; TPO receptor) signaling pathway play a certain role in the development of MF. In the present study, we aimed to investigate the relationship between fibrocytes and MPL activation. We showed that TPO or a TPO receptor agonist directly induces fibrocyte differentiation using murine fibrocyte cell lines and a murine MF model. Conversely, elimination of macrophages expressing MPL by clodronate liposomes reversed the MF phenotype of the murine model, suggesting that fibrocyte differentiation induced by MPL activation contributes to the progression of MF. Furthermore, we revealed that SLAMF7high MPLhigh monocytes in human peripheral blood mononuclear cells were possible fibrocyte precursors and that these cells increased in number in MF patients not treated with ruxolitinib. Our findings confirmed a link between fibrocytes and the TPO/MPL signaling pathway, which could result in a greater understanding of the pathogenesis of MF and lead to the development of novel therapeutic interventions.


Assuntos
Mielofibrose Primária/etiologia , Mielofibrose Primária/metabolismo , Receptores de Trombopoetina/metabolismo , Animais , Medula Óssea/metabolismo , Medula Óssea/patologia , Diferenciação Celular , Linhagem Celular , Ácido Clodrônico/farmacologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imuno-Histoquímica , Janus Quinase 2/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Monócitos/citologia , Monócitos/metabolismo , Fenótipo , Mielofibrose Primária/patologia , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Trombopoetina/metabolismo
14.
Cancer Res ; 42(8 Suppl): 3299s-3306s, 1982 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6177401

RESUMO

Two distinct aromatase-active protein complexes are solubilized by use of deoxycholate and separated by diethylamino-ethyl-cellulose chromatography from lyophilized powder of 900 X g precipitate fraction of human term placenta. Aromatase activity to produce estriol, the major estrogen of human pregnancy, was designated to be aromatase I activity and measured by estriol formation from 16 alpha-hydroxytestosterone. Aromatases II activity was the designation for that which produces estrone plus estradiol and was measured by androstenedione aromatization. Aromatases II and I are eluted with 0.25 M and 0.5 M Tris buffer, respectively, from diethylaminoethyl-cellulose column in an Mr 2 million soluble complex. Each has a minimum active Mr 135,000 subunit, which is isolated by Bio-Gel filtration in the presence of detergents, and consists of a reduced nicotinamide adenine dinucleotide phosphate:cytochrome P-450 reductase (Mr 83,000) and a cytochrome P-450 (Mr 52,000). Aromatase II was found to be the major aromatase, containing approximately five times more aromatase activity, reduced nicotinamide adenine dinucleotide phosphate:cytochrome c reductase activity, cytochrome P-450, and protein than did aromatase I. Antibodies raised in rabbits against aromatase II and its reductase suppressed aromatase II activity of breast cancer tissues, as well as of adult male lung tissue, placental microsomes, and solubilized aromatase. The breast carcinoma specimens responded to the antibodies in different degrees, but there was no response to antibodies against rat liver cytochrome P-450. The results indicate similar antigenic structures for breast cancer and placental aromatase but not for rat liver cytochrome P-450.


Assuntos
Anticorpos/imunologia , Aromatase/isolamento & purificação , Neoplasias da Mama/enzimologia , Carcinoma Intraductal não Infiltrante/enzimologia , Oxirredutases/isolamento & purificação , Placenta/imunologia , Adulto , Idoso , Formação de Anticorpos , Aromatase/imunologia , Cromatografia DEAE-Celulose , Epitopos , Estrogênios/biossíntese , Estrona/biossíntese , Estrona/imunologia , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez
15.
Cancer Gene Ther ; 23(1): 24-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26584532

RESUMO

Ovarian cancer (OC) in which carbonyl reductase 1 (CBR1) is highly expressed has good prognosis. The aims of this study were to determine the optimal conditions for delivering CBR1 DNA to OC cells via a polyamidoamine (PAMAM) dendrimer and to examine the therapeutic effectiveness of using a CBR1/PAMAM dendrimer to treat OC. The ratio for mixture of the PAMAM dendrimer and CBR1 plasmid DNA was defined as the ratio of the number of moles of phosphate groups in plasmid DNA to the number of moles of amino groups in PAMAM, which was expressed as N/P ratio. Mice were intraperitoneally injected with OC cells (HRA) to create peritoneal carcinomatosis. CBR1 DNA/PAMAM dendrimer complexes were administered on alternate days after injection of HRA cells. Cells transfected with CBR1 DNA at N/P ratio of 20:1 for 48 h produced the highest level of CBR1 expression. All the mice in control group died prior to day 25. However, all the mice administered the CBR1 DNA/PAMAM dendrimer survived (P<0.001). Use of a PAMAM dendrimer allowed CBR1 DNA to be delivered to cancer cells. The results suggested that CBR1 DNA/PAMAM dendrimer complexes may represent a potent gene therapy for the treatment of advanced OC.


Assuntos
Oxirredutases do Álcool/genética , Dendrímeros/química , Terapia Genética , Neoplasias Ovarianas/terapia , Poliaminas , Transfecção , Animais , Carcinoma/genética , Carcinoma/terapia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Nus , Neoplasias Ovarianas/genética , Plasmídeos , Transgenes , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Bone Joint J ; 103-B(9): 1551, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34465162
17.
Biochim Biophys Acta ; 1495(3): 237-49, 2000 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-10699463

RESUMO

Irradiation increases the generation of reactive oxygen intermediates, including hydrogen peroxide (H(2)O(2)). Myeloperoxidase (MPO), a heme-containing glycoprotein located in the primary granules of polymorphonuclear leukocytes and monocytes, reacts with H(2)O(2) and halide ion and produces a more potent microbicidal oxidant, hypochlorous acid (HOCl). Human HL60 promyelocytes constitutively had high levels of MPO protein and mRNA. Irradiation decreased the levels of MPO transcripts; the decrease in MPO transcripts by irradiation occurred in an almost dose-dependent manner. HL60 cells produce tumor necrosis factor alpha (TNFalpha), and irradiation markedly increased the TNFalpha production in these cells; in turn, TNFalpha decreased the levels of MPO transcripts in these cells. Furthermore, treatment of cells with anti-TNFalpha antibody blocked the reduction of MPO by irradiation. We also found that irradiation decreased the levels of the MPO mRNA with concomitant increased levels of TNFalpha mRNA in differentiation-induced HL60 cells and human THP-1 monocytic cells. Irradiation reduced the rate of MPO transcription but had only a slight effect on the half-life of MPO mRNA in HL60 cells. Our results suggest that irradiation reduces the steady-state levels of MPO mRNA mainly at transcriptional level and the endogenous production of TNFalpha is required for the reduction by irradiation in HL60 cells.


Assuntos
Raios gama , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Peroxidase/biossíntese , Fator de Necrose Tumoral alfa/fisiologia , Diferenciação Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Células HL-60 , Humanos , Proteínas Proto-Oncogênicas c-myc/genética , Estabilidade de RNA , RNA Mensageiro/metabolismo , RNA Mensageiro/efeitos da radiação , Ativação Transcricional/efeitos da radiação , Fator de Necrose Tumoral alfa/genética
18.
Biochim Biophys Acta ; 1163(2): 195-200, 1993 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-8490051

RESUMO

Mutant aromatase cytochrome P-450s, expressed in CHO cells after transfection with cDNAs, have been characterized in terms of their catalytic efficiencies. After solubilization from microsomes, specific aromatase P-450 content of wild-type and mutants Pro308Phe, Asp309Asn, Asp309Ala and Phe406Arg was quantitated by a sandwich enzyme-linked immunosorbent assay (ELISA). Microsomal aromatase activity was determined by the 3H-water method using [1 beta-3H]androstenedione as substrate. Estimations of the actual turnover rate (catalytic efficiency) were derived from the combined data. The P-450 content in the mutants varied but was always less than that in the wild type. Hence, the decreases in the Vmax observed in the mutant enzymes did not correlate completely with reductions in catalytic effectiveness. In recent studies on the structure-function relationship of aromatase cytochrome P-450, the observed reduction of enzyme activity in terms of Vmax following site-directed mutagenesis led to the assumption that there was a corresponding loss of catalytic effectiveness. The present study reveals that a lower P-450 content can contribute significantly to decreasing catalytic activity in the mutants. In fact, in mutant Phe406Arg which exhibited virtually no catalytically active aromatase, the specific P-450 content was below the detectable level. Because of its location, the result of this latter mutation could be a major structural perturbation of the heme-binding property. Thus, interpretation of losses and reductions in aromatase activity resulting from single amino-acid replacement should take into account changes in the specific content of aromatase cytochrome P-450.


Assuntos
Aromatase/genética , Androstenodiona/metabolismo , Animais , Aromatase/metabolismo , Células CHO/metabolismo , Catálise , Cricetinae , Ensaio de Imunoadsorção Enzimática , Estrogênios/biossíntese , Expressão Gênica , Heme/metabolismo , Mutagênese Sítio-Dirigida , Transfecção
19.
J Leukoc Biol ; 68(1): 87-96, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10914494

RESUMO

HL-60 cells undergo apoptosis when placed at room temperature (RT) [Shimura et al. (1997) FEBS Lett. 417, 379-384]. We report that superoxide anion radical, one of the reactive oxygen species (ROS), was produced after RT treatment. Affinity blot analysis with a biotinylated YVAD-CHO detected the generation of processed peptides with molecular masses of 15-25 kDa. Activation of such an ICE-like protease was completely abolished by N-acetylcysteine and exogenously expressed Bcl-2, known as antioxidants. We concluded that oxidative stress was a critical factor in the signal cascade of the apoptosis. Western blot analysis and experiments using tetrapeptide inhibitors suggested that caspases-1, -3, -4, -6, and -9 did not have an essential role in the apoptotic cascade. It is interesting that cyclosporin A (CsA) blocked RT-induced apoptosis with an inhibition of cytochrome c release from mitochondria. CsA, however, generated a significant amount of ROS with considerable reduction of mitochondrial membrane potential, implying that oxidative stress was one necessary factor for RT-induced apoptosis. It is also likely that mitochondrial membrane potential and the release of apoptotic factors from cytoplasm are differently regulated. Taken together with the reports that some Burkitt lymphoma cells showed apoptosis when exposed at low temperature followed by rewarming, and that hepatocytes or liver endothelial cells are susceptible to cold-induced apoptosis through the ROS function, we propose that studying the mechanism of RT-induced apoptosis of HL-60 cells may provide a therapeutic strategy for pathological conditions involving ROS, such as neurodegenerative diseases and ischemia.


Assuntos
Apoptose/fisiologia , Células HL-60/citologia , Estresse Oxidativo , Temperatura , Clorometilcetonas de Aminoácidos/farmacologia , Biotina/análogos & derivados , Biotina/farmacologia , Inibidores de Caspase , Caspases/fisiologia , Ciclosporina/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Grupo dos Citocromos c/metabolismo , Endopeptidases/fisiologia , Genes bcl-2 , Células HL-60/efeitos dos fármacos , Humanos , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Peso Molecular , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/fisiologia , Oligopeptídeos/farmacologia , Permeabilidade/efeitos dos fármacos , Inibidores de Proteases/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Proteínas Recombinantes de Fusão/fisiologia , Superóxido Dismutase/farmacologia , Superóxidos/metabolismo , Proteína bcl-X
20.
Mol Immunol ; 36(7): 423-32, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10449095

RESUMO

The crystal structure of a Fab fragment (Fab3-2C2) of a monoclonal antibody raised against aromatase cytochrome P450 P450arom) has been determined at 3.0 A resolution. P450arom is a membrane bound enzyme responsible for the catalysis of indrogens to estrogens, the process of aromatization, and hence has been implicated in hormone-dependent breast cancer. The Fab fragment of MAb3-2C2 IgG suppresses P450arom activity in a dose dependent manner. The Fab3-2C2 molecule crystallizes n the space group P2(1)2(1)2(1) with a unit cell of a= 154.89 A, b = 73.51 A, and c= 36.90 A. The crystal structure consists of a light and a heavy chain in the asymmetric unit, each characterized by the greek-key antiparallel beta barrel folding seen in all Fab structures. The average elbow angle between the two domains is 143 degrees. Modeling of the interactions between the variable domains of the antibody and a known model of P450arom maps the epitope to a region of the enzyme that is consistent with the available biochemical data and the activity-suppressing function of the antibody. The epitope mapping result is further supported by the inability of MAb3-2C2 IgG to suppress the activity of, or to interact with placental porcine P450arom, which is 81% identical (86% similar) to human P450arom but has a few key substitutions in the putative epitope region.


Assuntos
Anticorpos Monoclonais/química , Reações Antígeno-Anticorpo , Inibidores da Aromatase , Aromatase/imunologia , Fragmentos Fab das Imunoglobulinas/química , Sequência de Aminoácidos , Animais , Aromatase/isolamento & purificação , Sequência de Bases , Sequência Conservada , Cristalografia por Raios X , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Imunoglobulina G/química , Imunoglobulina G/imunologia , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Suínos
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