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1.
Biochem J ; 477(1): 45-60, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31820794

RESUMO

Membrane-active peptides have been extensively studied to probe protein-membrane interactions, to act as antimicrobial agents and cell-penetrating peptides (CPPs) for the delivery of therapeutic agents to cells. Hundreds of membrane-active sequences acting as CPPs have now been described including bioportides that serve as single entity modifiers of cell physiology at the intracellular level. Translation of promising CPPs in pre-clinical studies have, however, been disappointing as only few identified delivery systems have progressed to clinical trials. To search for novel membrane-active peptides a sequence from the EGFR juxtamembrane region was identified (named EJP18), synthesised, and examined in its L- and D-form for its ability to mediate the delivery of a small fluorophore and whole proteins to cancer cell lines. Initial studies identified the peptide as being highly membrane-active causing extensive and rapid plasma membrane reorganisation, blebbing, and toxicity. At lower, non-toxic concentrations the peptides outperformed the well-characterised CPP octaarginine in cellular delivery capacity for a fluorophore or proteins that were associated with the peptide covalently or via ionic interactions. EJP18 thus represents a novel membrane-active peptide that may be used as a naturally derived model for biophysical protein-membrane interactions or for delivery of cargo into cells for therapeutic or diagnostic applications.


Assuntos
Peptídeos Penetradores de Células/farmacologia , Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/tratamento farmacológico , Receptores ErbB/farmacologia , Proteínas de Fluorescência Verde/administração & dosagem , Células HeLa , Humanos , Células MCF-7 , Domínios Proteicos
2.
Int J Obes (Lond) ; 42(2): 231-243, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28630461

RESUMO

BACKGROUND: Obesity is associated with gut microbiota dysbiosis, disrupted intestinal barrier and chronic inflammation. Given the high and increasing prevalence of obesity worldwide, anti-obesity treatments that are safe, effective and widely available would be beneficial. We examined whether the medicinal mushroom Antrodia cinnamomea may reduce obesity in mice fed with a high-fat diet (HFD). METHODS: Male C57BL/6J mice were fed a HFD for 8 weeks to induce obesity and chronic inflammation. The mice were treated with a water extract of A. cinnamomea (WEAC), and body weight, fat accumulation, inflammation markers, insulin sensitivity and the gut microbiota were monitored. RESULTS: After 8 weeks, the mean body weight of HFD-fed mice was 39.8±1.2 g compared with 35.8±1.3 g for the HFD+1% WEAC group, corresponding to a reduction of 4 g or 10% of body weight (P<0.0001). WEAC supplementation reduced fat accumulation and serum triglycerides in a statistically significant manner in HFD-fed mice. WEAC also reversed the effects of HFD on inflammation markers (interleukin-1ß, interleukin-6, tumor necrosis factor-α), insulin resistance and adipokine production (leptin and adiponectin). Notably, WEAC increased the expression of intestinal tight junctions (zonula occludens-1 and occludin) and antimicrobial proteins (Reg3g and lysozyme C) in the small intestine, leading to reduced blood endotoxemia. Finally, WEAC modulated the composition of the gut microbiota, reducing the Firmicutes/Bacteroidetes ratio and increasing the level of Akkermansia muciniphila and other bacterial species associated with anti-inflammatory properties. CONCLUSIONS: Supplementation with A. cinnamomea produces anti-obesogenic, anti-inflammatory and antidiabetic effects in HFD-fed mice by maintaining intestinal integrity and modulating the gut microbiota.


Assuntos
Antrodia/química , Dieta Hiperlipídica , Disbiose/dietoterapia , Microbioma Gastrointestinal/efeitos dos fármacos , Inflamação/dietoterapia , Obesidade/dietoterapia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Modelos Animais de Doenças , Disbiose/fisiopatologia , Resistência à Insulina/fisiologia , Masculino , Medicina Tradicional , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/fisiopatologia
3.
Transplant Proc ; 48(2): 507-11, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27109988

RESUMO

BACKGROUND: Intestinal stem cells (ISCs) are responsible for the regeneration of intestinal epithelium. In a previous study, we demonstrated that sodium selenite is 1 of the key factors that enhances the growth of ISCs in crypt culture medium. The goal of the present article was to investigate the effect of selenite on the proliferative and antioxidative activities of ISCs. MATERIALS AND METHODS: Five-week old BALB/C mice were administered phosphate-buffered saline or sodium selenite (4 mg/kg/d) for 7 days before ISCs were harvested. The proliferative activity of ISC was indexed by the growth of crypt organoids. The messenger RNA expression levels of ISC markers were quantified by using real-time polymerase chain reaction. The activity of antioxidative enzymes was assayed for glutathione peroxidase (GPx), thioredoxin reductase (TrxR), and superoxide dismutase. RESULTS: Treatment with sodium selenite induced a 1.88-fold increase in the growth number of organoids from ISCs, with elevated expression of leucine-rich repeat-containing G-protein-coupled receptor 5, B lymphoma Moloney murine leukemia virus insertion region homolog-1, and Musashi-1, compared with the ISCs from control samples treated with phosphate-buffered saline. The antioxidative activity of GPx and TrxR was significantly enhanced in the selenite-treated groups (1.55- and 1.23-fold increases, respectively). CONCLUSIONS: Selenite positively regulated the proliferation of ISCs and activated the expression of ISC markers. The elevated activity of GPx and TrxR induced by selenite should promote the antioxidative ability of ISCs and benefit the growth of organoids.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Organoides/efeitos dos fármacos , Ácido Selenioso/farmacologia , Células-Tronco/efeitos dos fármacos , Oligoelementos/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Mucosa Intestinal/patologia , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores Acoplados a Proteínas G/biossíntese , Células-Tronco/citologia
4.
J Laryngol Otol ; 129(6): 607-10, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26074261

RESUMO

BACKGROUND: Pregnancy-associated pyogenic granuloma (pregnancy tumour) is not uncommon. However, control of severe bleeding associated with the lesion by transarterial embolisation has never been reported. CASE REPORT: We report the case of a 33-year-old pregnant woman (34 weeks gestation) who presented with a pregnancy-associated pyogenic granuloma of the mandibular gingiva with a life-threatening haemorrhage. The bleeding stopped soon after transarterial micro-embolisation and regressed after one month; thus, no further surgical excision was needed. The patient was free of post-operative wound pain and infection, and there was no recurrence after one year of follow up. CONCLUSION: In general, surgical excision is the first treatment choice for pregnancy tumours. However, it is limited by the risk of marked deformity or incomplete excision when large lesions or difficult surgical areas are encountered. For large tumours, transarterial embolisation may be a safer alternative.


Assuntos
Embolização Terapêutica/métodos , Doenças da Gengiva/complicações , Granuloma Piogênico/complicações , Hemorragia/terapia , Complicações na Gravidez , Adulto , Feminino , Hemorragia/etiologia , Humanos , Gravidez
5.
Cell Death Differ ; 22(10): 1590-604, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25633197

RESUMO

Colorectal carcinoma (CRC) is characterized by unlimited proliferation and suppression of apoptosis, selective advantages for tumor survival, and chemoresistance. Lipopolysaccharide (LPS) signaling is involved in both epithelial homeostasis and tumorigenesis, but the relative roles had by LPS receptor subunits CD14 and Toll-like receptor 4 (TLR4) are poorly understood. Our study showed that normal human colonocytes were CD14(+)TLR4(-), whereas cancerous tissues were CD14(+)TLR4(+), by immunofluorescent staining. Using a chemical-induced CRC model, increased epithelial apoptosis and decreased tumor multiplicity and sizes were observed in TLR4-mutant mice compared with wild-type (WT) mice with CD14(+)TLR4(+) colonocytes. WT mice intracolonically administered a TLR4 antagonist displayed tumor reduction associated with enhanced apoptosis in cancerous tissues. Mucosa-associated LPS content was elevated in response to CRC induction. Epithelial apoptosis induced by LPS hypersensitivity in TLR4-mutant mice was prevented by intracolonic administration of neutralizing anti-CD14. Moreover, LPS-induced apoptosis was observed in primary colonic organoid cultures derived from TLR4 mutant but not WT murine crypts. Gene silencing of TLR4 increased cell apoptosis in WT organoids, whereas knockdown of CD14 ablated cell death in TLR4-mutant organoids. In vitro studies showed that LPS challenge caused apoptosis in Caco-2 cells (CD14(+)TLR4(-)) in a CD14-, phosphatidylcholine-specific phospholipase C-, sphingomyelinase-, and protein kinase C-ζ-dependent manner. Conversely, expression of functional but not mutant TLR4 (Asp299Gly, Thr399Ile, and Pro714His) rescued cells from LPS/CD14-induced apoptosis. In summary, CD14-mediated lipid signaling induced epithelial apoptosis, whereas TLR4 antagonistically promoted cell survival and cancer development. Our findings indicate that dysfunction in the CD14/TLR4 antagonism may contribute to normal epithelial transition to carcinogenesis, and provide novel strategies for intervention against colorectal cancer.


Assuntos
Apoptose , Carcinogênese , Neoplasias Colorretais/metabolismo , Células Epiteliais/fisiologia , Receptores de Lipopolissacarídeos/fisiologia , Receptor 4 Toll-Like/fisiologia , Animais , Células CACO-2 , Colo/metabolismo , Colo/fisiologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Células Epiteliais/metabolismo , Humanos , Camundongos , Transdução de Sinais
6.
Blood Cancer J ; 5: e339, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26832848

RESUMO

Epithelial-mesenchymal transition (EMT) is a critical process for inducing stem-like properties of epithelial cancer cells. However, the role of EMT inducers in hematological malignancies is unknown. Twist1, an EMT inducer necessary for cell migration, has recently been found to have transcriptionally regulatory activity on the expression of Bmi1, and these two are capable of promoting tumorigenesis in a synergized manner. Knowing that Bmi1 expression is essential for maintenance of leukemic stem cells, we speculate that Twist1 might govern the pathogenesis of acute myeloid leukemia (AML) development as well. We found that upregulated Twist1 increased Bmi1 expression in AML and endued leukemic cells a higher proliferative potential and increased resistance to apoptosis. In primary AML samples, there was strong positive correlation between the expression levels of Twist1 and Bmi1. AML patients whose leukemic blasts harbored overexpressed Twist1 had a more aggressive clinical phenotype, but they were more likely to have a better clinical outcome after standard therapy. In vitro studies confirmed that Twist1-overexpressing leukemic cells were more susceptible to cytarabine, but not daunorubicin, cytotoxicity. Our findings suggest that, in a subset of AML patients, Twist1 has a prominent role in the pathogenesis of the disease that leads to unique clinical phenotypes.


Assuntos
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Proteínas Nucleares/genética , Proteína 1 Relacionada a Twist/genética , Antineoplásicos/uso terapêutico , Medula Óssea , Linhagem Celular , Citarabina/uso terapêutico , Transição Epitelial-Mesenquimal , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Proteínas Nucleares/metabolismo , Complexo Repressor Polycomb 1/metabolismo , Prognóstico , Proteína 1 Relacionada a Twist/metabolismo
7.
Clin Microbiol Infect ; 18(6): E149-57, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22439904

RESUMO

The limited sensitivity of serological tests for mycobacterial antigens has encouraged the development of a nanoparticle probe specific for the extrapulmonary form of Mycobacterium tuberculosis (Mtb). We developed an innovative probe comprised of super-paramagnetic iron oxide (SPIO) nanoparticles conjugated with Mtb surface antibody (MtbsAb-nanoparticles) to provide ultrasensitive imaging of biomarkers involved in extrapulmonary Mtb infection. MtbsAb-nanoparticles were significantly conjugated with Mtb bacilli. The extent of contrast enhancement reduction on magnetic resonance imaging (MRI) for Mtb and human monocytic THP1 cells was proportional to the concentration of MtbsAb-nanoparticles. When MtbsAb-nanoparticles were intravenously injected into mice bearing Mtb granulomas, the granulomatous site showed a 14-fold greater reduction in signal intensity enhancement on T(2) -weighted MR images compared with an opposing site that received PBS injection. Mtb sAb-nanoparticles represent a new non-invasive technology for the diagnosis of extrapulmonary Mtb.


Assuntos
Anticorpos Antibacterianos , Compostos Férricos , Mycobacterium tuberculosis/isolamento & purificação , Nanopartículas , Tuberculose/diagnóstico , Animais , Imageamento por Ressonância Magnética/métodos , Camundongos
8.
J Bone Joint Surg Br ; 94(2): 227-30, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22323691

RESUMO

In patients with traumatic brain injury and fractures of long bones, it is often clinically observed that the rate of bone healing and extent of callus formation are increased. However, the evidence has been unconvincing and an association between such an injury and enhanced fracture healing remains unclear. We performed a retrospective cohort study of 74 young adult patients with a mean age of 24.2 years (16 to 40) who sustained a femoral shaft fracture (AO/OTA type 32A or 32B) with or without a brain injury. All the fractures were treated with closed intramedullary nailing. The main outcome measures included the time required for bridging callus formation (BCF) and the mean callus thickness (MCT) at the final follow-up. Comparative analyses were made between the 20 patients with a brain injury and the 54 without brain injury. Subgroup comparisons were performed among the patients with a brain injury in terms of the severity of head injury, the types of intracranial haemorrhage and gender. Patients with a brain injury had an earlier appearance of BCF (p < 0.001) and a greater final MCT value (p < 0.001) than those without. There were no significant differences with respect to the time required for BCF and final MCT values in terms of the severity of head injury (p = 0.521 and p = 0.153, respectively), the types of intracranial haemorrhage (p = 0.308 and p = 0.189, respectively) and gender (p = 0.383 and p = 0.662, respectively). These results confirm that an injury to the brain may be associated with accelerated fracture healing and enhanced callus formation. However, the severity of the injury to the brain, the type of intracranial haemorrhage and gender were not statistically significant factors in predicting the rate of bone healing and extent of final callus formation.


Assuntos
Calo Ósseo/fisiopatologia , Lesões Encefálicas/fisiopatologia , Fraturas do Fêmur/fisiopatologia , Consolidação da Fratura/fisiologia , Traumatismo Múltiplo/fisiopatologia , Adolescente , Adulto , Calo Ósseo/patologia , Feminino , Fraturas do Fêmur/cirurgia , Fixação Intramedular de Fraturas/métodos , Escala de Coma de Glasgow , Humanos , Masculino , Período Pós-Operatório , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
9.
Neurogastroenterol Motil ; 23(4): 362-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21199176

RESUMO

BACKGROUND: Identification of neuronal progenitor/stem cells in the postnatal gut suggests the development of transplantation approaches to enteric nervous system (ENS) diseases. Many clinical applications would require engrafting large segments of postnatal gut in vivo. We investigated the ability of unselected gut cells vs selected enteric neural crest stem cells (eNCSCs) to engraft and differentiate in the postnatal gut in the Hirschsprung disease (HD, ednrb(sl/sl)) rat. METHODS: Total intestinal cells or eNCSCs (α(4) integrin(+), p75(++)) from embryonic day (E)14.5 rats carrying a marker transgene (human placental alkaline phosphatase, hPAP) were injected intraperitoneally (i.p.) into neonatal HD rats and their healthy littermates. The entire gut was systematically analyzed 3 weeks later for hPAP(+) cells between the serosal surface and the muscularis mucosae. Engrafted cells were examined for HuC/D, S-100B, neuropeptide Y (NPY), neuronal nitric oxide synthase (nNOS), and vasoactive intestinal peptide (VIP) expression. KEY RESULTS: No rats (0/33) injected with unselected cells had hPAP(+) cells in the ENS that expressed neuronal or glial markers. 5/11 healthy and 4/5 HD rats injected with eNCSCs showed widespread but low density engraftment in the ENS with cells expressing neuronal or glial markers. Neurons expressed nNOS and VIP. There was no engraftment in the colon of either HD or wildtype rats. CONCLUSIONS & INFERENCES: Enteric neural crest stem cells will engraft diffusely throughout the postnatal gut of HD rats and differentiate into neurons and glia. Engraftment is not uniform, likely related to age-dependent changes in the gut mesenchyme. Intraperitoneal injection is easily performed in sick neonates and may be developed as a technique to supply exogenous ENS cells to the diseased postnatal gut.


Assuntos
Doença de Hirschsprung/cirurgia , Intestinos/inervação , Crista Neural/transplante , Transplante de Células-Tronco/métodos , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Injeções Intraperitoneais , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Ratos , Ratos Endogâmicos WKY , Peptídeo Intestinal Vasoativo/metabolismo
10.
Ann Oncol ; 20(7): 1249-56, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19276396

RESUMO

BACKGROUND: The study compared the efficacy of a first-line treatment with day 1 i.v. vinorelbine (NVBiv) and day 8 oral vinorelbine (NVBo) versus docetaxel (DCT) in a cisplatin-based combination in advanced non-small-cell lung cancer, in terms of time to treatment failure (TTF), overall response, progression-free survival (PFS), overall survival (OS), tolerance and quality of life (QoL). METHODS: Patients were randomly assigned to receive cisplatin 80 mg/m2 with NVBiv 30 mg/m2 on day 1 and NVBo 80 mg/m2 on day 8 every 3 weeks, after a first cycle of NVBiv 25 mg/m2 on day 1 and NVBo 60 mg/m2 on day 8 (arm A) or cisplatin 75 mg/m2 and DCT 75 mg/m2 on day 1 every 3 weeks (arm B), for a maximum of six cycles in both arms. RESULTS: From 2 February 2004 to 1 January 2006, 390 patients were entered in a randomised study and 381 were treated. The patient characteristics are as follows (arms A/B): metastatic (%) 80.5/84.8; patients with three or more organs involved (%) 45.3/40.8; median age 59.4/62.1 years; male 139/146; squamous (%) 34.2/33.5; adenocarcinoma (%) 41.6/39.3; median TTF (arms A/B in months) [95% confidence interval (CI)]: 3.2 (3.0-4.2), 4.1 (3.4-4.5) (P = 0.19); overall response (arms A/B) (95% CI): 27.4% (21.2% to 34.2%), 27.2% (21.0% to 34.2%); median PFS (arms A/B in months) (95% CI): 4.9 (4.4-5.9), 5.1 (4.3-6.1) (P = 0.99) and median OS (arms A/B in months) (95% CI): 9.9 (8.4-11.6), 9.8 (8.8-11.5) (P = 0.58). The median survival for squamous histology was 8.87/9.82 months and for adenocarcinoma 11.73/11.60 months for arms A and B, respectively. Main haematological toxicity was grade 3-4 neutropenia: 24.4% (arm A) and 28.8% (arm B). QoL as measured by the Lung Cancer Symptom Scale was similar in both arms. CONCLUSIONS: Both arms provided similar efficacy in terms of response, time-related parameters and QoL, with an acceptable tolerance profile. In the current Global Lung Oncology Branch trial 3, NVBo was shown to be effective as a substitute for the i.v. formulation. This can relieve the burden of the i.v. injection on day 8 and can optimise the hospital's resources and improve patient convenience.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Administração Oral , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Terapia Combinada , Intervalo Livre de Doença , Docetaxel , Esquema de Medicação , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Estimativa de Kaplan-Meier , Masculino , Estudos Prospectivos , Qualidade de Vida , Análise de Sobrevida , Taxoides/administração & dosagem , Resultado do Tratamento , Vimblastina/administração & dosagem , Vimblastina/análogos & derivados , Vinorelbina
11.
Pediatr Cardiol ; 29(2): 292-6, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17874221

RESUMO

High expression of circulating vascular endothelial growth factor (VEGF) has been reported in patients with Kawasaki disease (KD). In the pathophysiology of KD, VEGF is considered to be involved, especially in the development of coronary artery lesions. This study aimed to examine whether the VEGF-634 promoter polymorphism is a marker of KD susceptibility or severity in Chinese patients in Taiwan. The study included 93 KD patients and 96 normal control subjects. Genotype and allelic frequencies for the VEGF gene polymorphism in the two groups were compared. The number of individuals with the VEGF-634 G/G genotype was significantly greater among the patients with KD than among the healthy control subjects (p = 0.011). The odds ratio for the development of KD in individuals with the VEGF-634 G/G genotype was found to be 2.03 (95% confidence interval [CI], 1.14-3.63) compared with the VEGF-634 G/C and VEGF-634 C/C genotypes. No significant difference was observed in the genotype or allelic frequencies of VEGF C-634 G polymorphism between the patients with and those without coronary artery lesions. In conclusion, the results suggest that VEGF-634 G/G genotype may be involved in the development of KD in Taiwanese children.


Assuntos
DNA/genética , Síndrome de Linfonodos Mucocutâneos/genética , Polimorfismo Genético , Fator A de Crescimento do Endotélio Vascular/genética , Alelos , Pré-Escolar , Feminino , Seguimentos , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Incidência , Lactente , Masculino , Síndrome de Linfonodos Mucocutâneos/sangue , Síndrome de Linfonodos Mucocutâneos/epidemiologia , Reação em Cadeia da Polimerase , Prognóstico , Taiwan/epidemiologia , Fator A de Crescimento do Endotélio Vascular/biossíntese
12.
Br J Cancer ; 96(11): 1659-66, 2007 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-17505517

RESUMO

Survivin is an oncogenic protein involved in cell division and acts as an anti-apoptotic factor. It is highly expressed in most cancers and is associated with chemotherapy resistance, increased tumour recurrence, and shorter patient survival. This makes anti-survivin therapy an attractive cancer treatment strategy. These functions are mediated by several survivin spliced variants, whose expression may correlate with cancer progression. One of the spliced variants, survivin-DeltaEx3, is known to inhibit apoptosis, through undefined mechanisms. Here, we characterised these mechanisms upon TNFalpha-mediated apoptosis, and showed that survivin-DeltaEx3 acts as an adaptor, allowing the formation of a complex between Bcl-2 and activated caspase-3. The Bcl-2/survivin-DeltaEx3 complex, but not survivin-DeltaEx3 itself, inhibits the activity of caspase-3. Bcl-2 is therefore linked to the postmitochondrial apoptotic machinery by survivin-DeltaEx3. Thus, survivin-DeltaEx3 plays a key role in the inhibition of caspase-3 activity, and in the control of the mitochondrial checkpoint of apoptosis. This study suggests that targeting survivin-DeltaEx3, rather than survivin alone, could be relevant for treating human cancers.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/fisiologia , Proteínas de Neoplasias/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Apoptose/genética , Caspase 3/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Inibidoras de Apoptose/fisiologia , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Modelos Biológicos , Modelos Moleculares , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Survivina
13.
Oncogene ; 25(14): 1991-2003, 2006 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-16301996

RESUMO

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer deaths worldwide and is highly correlated with hepatitis virus infection. Our previous report shows that a DEAD box RNA helicase, DDX3, is targeted and regulated by hepatitis C virus (HCV) core protein, which implicates the involvement of DDX3 in HCV-related HCC development. In this study, the potential role of DDX3 in hepatocarcinogenesis is investigated by examining its expression in surgically excised human HCC specimens. Here we report the differential deregulation of DDX3 expression in hepatitis virus-associated HCC. A significant downregulation of DDX3 expression is found in HCCs from hepatitis B virus (HBV)-positive patients, but not from HCV-positive ones, compared to the corresponding nontumor tissues. The expression of DDX3 is differentially regulated by the gender and, moreover, there is a tendency that the downregulation of DDX3 expression in HCCs is more frequent in males than in females. Genetic knockdown of DDX3 with small interfering RNAs (siRNA) in a nontransformed mouse fibroblast cell line, NIH-3T3, results in a premature entry to S phase and an enhancement of cell growth. This enhanced cell cycle progression is linked to the upregulation of cyclin D1 and the downregulation of p21(WAF1) in the DDX3 knockdown cells. In addition, constitutive reduction of DDX3 expression increases the resistance of NIH-3T3 cells to serum depletion-induced apoptosis and enhances the ras-induced anchorage-independent growth, indicating the involvement of DDX3 in cell growth control. These findings together with the previous study suggest that the deregulation of DDX3, a DEAD box RNA helicase with cell growth-regulatory functions, is involved in HBV- and HCV-associated pathogenesis.


Assuntos
Carcinoma Hepatocelular/genética , Divisão Celular/fisiologia , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Hepacivirus/patogenicidade , Neoplasias Hepáticas/genética , RNA Helicases/genética , Animais , Sequência de Bases , Western Blotting , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , RNA Helicases DEAD-box , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Camundongos , Dados de Sequência Molecular , Células NIH 3T3 , RNA Helicases/fisiologia , RNA Interferente Pequeno/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência do Ácido Nucleico
14.
J Orthop Res ; 23(2): 446-53, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15734261

RESUMO

Chondrogenic differentiation by mesenchymal progenitor cells (MPCs) is associated with cytokines such as transforming growth factor-beta 1 (TGF-beta1) and dexamethasone. Extracellular matrix (ECM) also regulates the differentiation by MPCs. To define whether ECM plays a functional role in regulation of the chondrogenic differentiation by MPCs, an in vitro model was used. That model exposed to dexamethasone, recombinant human TGF-beta1(rhTGF-beta1) and collagens. The results showed that MPCs incorporated with dexamethasone and rhTGF-beta1 increased proliferation and expression of glycosaminoglycan (GAG) after 14 days. Type II collagen enhanced the GAG synthesis, but did not increase alkaline phosphatase (ALP) activity. When adding dexamethasone and rhTGF-beta1 MPCs increased mRNA expression of Sox9. Incorporation with type II collagen, dexamethasone and rhTGF-beta1, MPCs induced mRNA expression of aggrecan and enhanced levels of type II collagen, and Sox9 mRNA. In contrast, incorporation with type I collagen, dexamethasone and rhTGF-beta1 MPCs reduced levels of aggrecan, and Sox9 mRNA, and showed no type II collagen mRNA. Altogether, these results indicate that type I and II collagen, in addition to the cytokine effect, may play a functional role in regulating of chondrogenic differentiation by MPCs.


Assuntos
Condrócitos/efeitos dos fármacos , Colágeno Tipo II/farmacologia , Colágeno Tipo I/farmacologia , Células-Tronco Mesenquimais/fisiologia , Agrecanas , Animais , Diferenciação Celular/efeitos dos fármacos , Condrócitos/citologia , Dexametasona/farmacologia , Proteínas da Matriz Extracelular/genética , Glicosaminoglicanos/biossíntese , Humanos , Lectinas Tipo C , Proteoglicanas/genética , RNA Mensageiro/análise , Coelhos , Fator de Crescimento Transformador beta/farmacologia , Fator de Crescimento Transformador beta1
15.
Int J Oral Maxillofac Surg ; 34(3): 311-20, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15741041

RESUMO

The aim of this study was to design a biodegradable implant, in the form of a reconstituted collagen template in order to promote and support regeneration of the temporomandibular joint disc. Bovine collagen (Major Type I) was pepsinized, reduced by beta-mercaptoethanol, and reconstituted by glutaraldehyde. The reconstitution of the collagen increased the resistance to biological degradation by collagenase, optimized the pore size and possessed maximum biological activity for tissue regeneration. Forty-four New Zealand rabbits underwent either sham surgical procedures or partial temporomandibular joint discectomy. In animals that underwent partial discectomy, the discs were replaced by either reconstituted collagen templates or subdermal grafts. Some of the surgerized animals did not receive any type of implant or disc substitute. Gross and histological examination of the surgerized temporomandibular joints was carried out at 1-, 2-, and 3-month intervals after surgery on the selected groups of animals. Marked arthritic changes were observed after 3 months in the partially discectomized joints without implantation. In contrast, the discs, which received a reconstituted collagen template or subdermal graft exhibited regeneration and nearly normal morpology. No foreign body response was observed in experimental groups 3 months after implantation. This study demonstrated that the reconstituted collagen did as well as subdermal grafts in supporting and facilitating regeneration of the disc and the former was found to have some advantages over the latter.


Assuntos
Implantes Absorvíveis , Regeneração Óssea/efeitos dos fármacos , Colágeno Tipo I/farmacologia , Disco da Articulação Temporomandibular/efeitos dos fármacos , Animais , Transplante Ósseo , Bovinos , Reação a Corpo Estranho , Masculino , Coelhos , Disco da Articulação Temporomandibular/fisiologia , Disco da Articulação Temporomandibular/cirurgia
16.
Anesthesiology ; 95(5): 1182-8, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11684988

RESUMO

BACKGROUND: In patients with acute respiratory distress syndrome, whether inverse ratio ventilation differs from high positive end-expiratory pressure (PEEP) for gas exchange under a similar mean airway pressure has not been adequately examined. The authors used arterial oxygenation, gastric intramucosal partial pressure of carbon dioxide (PiCO(2)), and pH (pHi) to assess whether pressure-controlled inverse ratio ventilation (PC-IRV) offers more benefits than pressure-controlled ventilation (PCV) with PEEP. METHODS: Seventeen acute respiratory distress syndrome patients were enrolled and underwent mechanical ventilation with a PCV inspiratory-to-expiratory ratio of 1:2, followed by PC-IRV 1:1 initially. Then, they were randomly assigned to receive PC-IRV 2:1, then 4:1 or 4:1, and then 2:1, alternately. The baseline setting of PCV 1:2 was repeated between the settings of PC-IRV 2:1 and 4:1. Mean airway pressure and tidal volume were kept constant by adjusting the levels of peak inspiratory pressure and applied PEEP. In each ventilatory mode, hemodynamics, pulmonary mechanics, arterial and mixed venous blood gas analysis, PiCO(2), and pHi were measured after a 1-h period of stabilization. RESULTS: With a constant mean airway pressure, PC-IRV 2:1 and 4:1 decreased arterial and mixed venous oxygenation as compared with baseline PCV 1:2. Neither the global oxygenation indices with oxygen delivery and uptake nor PiCO(2) and pHi were improved by PC-IRV. During PC-IRV, applied PEEP was lower, and auto-PEEP was higher. CONCLUSION: When substituting inverse ratio ventilation for applied PEEP to keep mean airway pressure constant, PC-IRV does not contribute more to better gas exchange and gastric intramucosal PiCO(2) and pHi than does PCV 1:2 for acute respiratory distress syndrome patients, regardless of the inspiratory-to-expiratory ratios.


Assuntos
Gasometria , Mucosa Gástrica/metabolismo , Hemodinâmica , Respiração com Pressão Positiva , Troca Gasosa Pulmonar , Respiração , Síndrome do Desconforto Respiratório/terapia , APACHE , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestésicos Intravenosos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Midazolam , Pessoa de Meia-Idade , Síndrome do Desconforto Respiratório/classificação
17.
Int J Pharm ; 222(2): 225-35, 2001 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-11427353

RESUMO

The influences of different mechanisms of penetration enhancers (such as menthol, azone, ethanol and nonivarnide) regarding the percutaneous absorption and skin irritation of ketoprofen formulations through rat skin were investigated by in vitro and in vivo study. The skin irritation degree at the end of the experiment (10 h) was deterinined by pathologic biopsy and colorimetry methods. In vitro, the menthol showed the most potent enhancing effect. Furthermore, the enhancement effect of a combination of menthol and nonivamide was higher than that of their individual use alone. In vivo the formulation containing 0.05% nonivantide, 5% menthol and 20% ethanol showed a higher penetration rate and an acceptable degree of skin irritation compared to a commercial product (Formax plus gel containing 3% ketoprofen), indicating that it could be used in the clinical situation.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Química Farmacêutica , Cetoprofeno/farmacocinética , Absorção Cutânea , Pele/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/efeitos adversos , Área Sob a Curva , Colorimetria , Géis , Meia-Vida , Cetoprofeno/efeitos adversos , Masculino , Ratos , Ratos Wistar , Pele/patologia
18.
Int J Pharm ; 215(1-2): 91-9, 2001 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-11250095

RESUMO

The skin permeation of estradiol from various proniosome gel formulations across excised rat skin was investigated in vitro. The encapsulation efficiency and size of niosomal vesicles formed from proniosomes upon hydration were also characterized. The encapsulation (%) of proniosomes with Span surfactants showed a very high value of about 100%. Proniosomes with Span 40 and Span 60 increased the permeation of estradiol across skin. Both penetration enhancer effect of non-ionic surfactant and vesicle-skin interaction may contribute to the mechanisms for proniosomes to enhance estradiol permeation. Niosome suspension (diluted proniosomal formulations) and proniosome gel showed different behavior in modulating transdermal delivery of estradiol across skin. Presence or absence of cholesterol in the lipid bilayers of vesicles did not reveal difference in encapsulation and permeation of the associated estradiol. The types and contents of non-ionic surfactant in proniosomes are important factors affecting the efficiency of transdermal estradiol delivery.


Assuntos
Estradiol/farmacocinética , Absorção Cutânea/fisiologia , Celulose , Cromatografia Líquida de Alta Pressão , Composição de Medicamentos , Estradiol/administração & dosagem , Membranas Artificiais , Microssomos , Tamanho da Partícula , Fosfatidilcolinas , Fosfolipídeos , Tensoativos
19.
J Toxicol Clin Toxicol ; 38(6): 679-81, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11185978

RESUMO

CASE REPORT: A 34-year-old male was admitted to the emergency department with the development of quadriparesis and respiratory failure due to hypokalemia after prolonged glue sniffing. The patient was subsequently given mechanical ventilatory support for respiratory failure. He was weaned from the ventilator 4 days later after potassium replacement. Toluene is an aromatic hydrocarbon found in glues, cements, and solvents. It is known to be toxic to the nervous system, hematopoietic system, and causes acid-base and electrolyte disorders. Acute respiratory failure with hypokalemia and rhabdomyolysis with acute renal failure should be considered as potential events in a protracted glue sniffing.


Assuntos
Acidose Tubular Renal/complicações , Adesivos/intoxicação , Hipopotassemia/complicações , Insuficiência Respiratória/etiologia , Rabdomiólise/complicações , Transtornos Relacionados ao Uso de Substâncias/complicações , Acidose Tubular Renal/induzido quimicamente , Acidose Tubular Renal/patologia , Doença Aguda , Adulto , Humanos , Hipopotassemia/induzido quimicamente , Hipopotassemia/patologia , Masculino , Insuficiência Respiratória/induzido quimicamente , Insuficiência Respiratória/patologia , Rabdomiólise/induzido quimicamente , Rabdomiólise/patologia , Transtornos Relacionados ao Uso de Substâncias/patologia , Tolueno/intoxicação
20.
Prenat Diagn ; 19(11): 1048-51, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10589057

RESUMO

The combination of in vitro fertilization (IVF) with PCR technologies enables diagnosis of single gene defects for preimplantation genetic diagnosis. This has been accomplished by two-step nested PCR, or PEP-PCR followed by nested PCR processes. To improve the detection of single cell genetic defects, the lysate of a single lymphocyte, with or without cystic fibrosis DeltaF508 mutation (CFDeltaF508), was incubated in a higher ionic strength solution containing mercaptoethanol prior to the addition of primers to the denatured cellular DNA. A single cell in 5 microl lysis buffer was incubated at 65 degrees C for 15 min, cooled, and neutralized with an equal volume of neutralizing buffer. A 5 microl aliquot of a solution X containing 50 mM MgCl(2), 1 M NaCl, and 10 mM mercaptoethanol was added to the neutralized cell lysate, followed by incubation at 93 degrees C for 15 min. The step was crucial to the successful amplification of CFDeltaF508 DNA fragment. The incubation of cell lysate in solution with the high level of sulphydryl reducing agent and a high ionic strength of about 0.45, at 93 degrees C for 15 min, might denature many chromatin-binding proteins and also ensure the complete dissociation of dsDNA. After the addition of PCR mix, the resulting reaction mixture still contained a sufficient level of sulphydryl reducing agent and 0.135 total ionic strength. This might reduce significantly the interference of various protein factors with DNA, and favour the primer-template annealing. The efficient initial annealing of the primers to target DNA sequences would facilitate PCR amplification efficacy. In conclusion, in more than 80 single cells tested (apart from one) the CFDeltaF508 defect was successfully demonstrated with the present protocol (>99 per cent), without using fluorescent primers and expensive automatic instrumentation.


Assuntos
Fibrose Cística/genética , Fertilização in vitro , Reação em Cadeia da Polimerase/economia , Diagnóstico Pré-Implantação , Análise Custo-Benefício , DNA/análise , Fragmentação do DNA , Primers do DNA , Feminino , Fertilização in vitro/métodos , Amplificação de Genes , Humanos , Linfócitos , Mutação , Reação em Cadeia da Polimerase/métodos , Gravidez , Diagnóstico Pré-Implantação/métodos
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