Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Dis Markers ; 2022: 8316335, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35111269

RESUMO

BACKGROUND: Exposure to nicotine has been observed associated with tumor progression, metastasis, and therapy resistance of many cancers. Hepatocellular carcinoma (HCC) is one major cancer related to the liver and the most difficult to treat malignancies worldwide. The underlying mechanism of nicotine in the stimulation of HCC tumorigenesis is still not studied well. METHODS: Classically, nicotine binds to nicotinic acetylcholine receptors (nAChRs) and induces many downstream cancer-associated signaling pathways. Big data analysis is used to explore the importance of a7nAChR-Jak2 axis in the progression of hepatocellular carcinoma. Bioinformatic analysis was performed to determine gene associated with a7nAChR-Jak2 axis of HCC patients. Biological importance of a7nAChR-Jak2 axis was investigated in vitro (Hun7 and HepG2 cell lines), and athymic nude mouse models bearing HepG2-HCC cells xenografts were established in vivo. RESULT: We found that nicotine exposure stimulated the HCC tumorigenicity by inducing the expression of one of the key nAChRs subunit that is α7nAChR as well as the expression of Janus kinase (JAK)-2. In both the in vitro and in vivo studies, the reduced overexpression of α7nAChR and increased sensitization of HCC towards treatment is observed with dehydrocrenatidine (DHCT), a novel and potent JAK family kinase inhibitor. Interestingly, DHCT treatment results in the reduction of the epithelial-mesenchymal transition process which leads to a significant reduction of clonogenicity, migratory, and invasive ability of HCC cells. Moreover, DHCT treatment also inhibits the cancer stem cell phenotype by inhibiting the tumor-sphere formation and reducing the number of ALDH1+ cells population in nicotine-stimulated HCC cells. CONCLUSIONS: Taken together, the presented results indicate the positive effect of inhibition of nicotine induced overexpression of α7nAChR and JAK2, unique to HCC. Thus, these findings suggest the nicotine effect on HCC progression via α7nAChR-mediated JAK2 signaling pathways, and DHCT treatment enhances the therapeutic potential of HCC patients via overcoming/reversing the effect of nicotine in HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Carbolinas , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Janus Quinase 2/metabolismo , Neoplasias Hepáticas/genética , Camundongos , Nicotina/farmacologia , Nicotina/uso terapêutico , Transdução de Sinais
2.
J Surg Res ; 167(2): 237-44, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19926099

RESUMO

BACKGROUND: Cholestasis occurs in a wide variety of human liver diseases, and hepatocellular injury is an invariant feature of cholestasis, causing liver dysfunction and inflammation, promoting fibrogenesis, and ultimately leading to liver failure. Insulin-like growth factor 1 (IGF1) acts in an autocrine and paracrine manner to promote glucose utilization, using phosphatidylinositol 3 kinase (PI3 K)/Akt, the downstream glycogen synthase kinase 3ß (GSK3ß), and anti-apoptotic pathways. This study investigated whether gene transfer of IGF1 could attenuate hepatocellular injury after bile duct ligation in rats. MATERIALS AND METHODS: Experiments were performed in 80 male Sprague-Dawley rats. Thirty minutes after bile duct ligation, hydrodynamics-based gene transfection with IGF1 plasmid via rapid tail vein injection. The rats were randomly divided into the following four groups: sham operated; BDL treated with pCMV-IGF1 gene; BDL treated with vehicle for pCMV-LacZ gene; and BDL only. RESULTS: IGF1 expression in liver after a single administration of IGF-1 plasmid was demonstrated. Liver function index, including serum alanine aminotransferase and aspartate aminotransferase, were significantly reduced in IGF1 gene transfer rats. We determined the mechanism of IGF1 gene transfer after BDL in terms of activation of Akt, inhibition of GSK3ß, and blockage of caspase-9 cleavage. Furthermore, hepatocyte stellate cell activation was markedly inhibited in IGF1 gene-treated rats. Apoptosis was significantly attenuated by IGF1 gene therapy. CONCLUSIONS: This study demonstrated that gene transfer of IGF1 could attenuate hepatocellular apoptosis and injury after bile duct ligation in rats.


Assuntos
Apoptose/fisiologia , Ductos Biliares/cirurgia , Colestase/patologia , Colestase/fisiopatologia , Hepatócitos/patologia , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/fisiologia , Animais , Caspase 9/fisiologia , Colestase/etiologia , Modelos Animais de Doenças , Técnicas de Transferência de Genes , Terapia Genética , Quinase 3 da Glicogênio Sintase/fisiologia , Glicogênio Sintase Quinase 3 beta , Hepatócitos/fisiologia , Ligadura/efeitos adversos , Fígado/fisiologia , Masculino , Plasmídeos/genética , Proteínas Proto-Oncogênicas c-akt/fisiologia , Ratos , Ratos Sprague-Dawley
3.
Ultrasound Med Biol ; 34(5): 841-52, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18222032

RESUMO

The shock wave is an effective noninvasive modality for resolving various tendon pathologies. However, scientific rationale and mechanism of shock wave therapy remains limited. This study aims to investigate the effects of shock waves and their biochemical mechanisms on tenocyte proliferation and collagen synthesis. Tenocytes harvested from Achilles tendons of Sprague-Dawley rats were used in this study. Cell viability was assayed by trypan blue exclusion methods. The colorimetric assay was determined to evaluate the mitochondria activity of the tenocytes after shock wave exposure. Synthesis of collagen, nitric oxide (NO) and transforming growth factor-beta1 (TGF-beta1) were determined and their gene expression was also studied. The results showed that there was a dose-dependent impairment of cell viability observed in 0.36 mJ/mm2 and 0.68 mJ/mm2 stimulation. In the proliferation assay, low energy level with low impulses (0.36 mJ/mm2 with 50 and 100 impulses) showed positive stimulatory effects, whereas the high energy level with high impulses (0.68 mJ/mm2 with 250 and 500 impulses) had significant inhibitory effects. At 0.36 mJ/mm2, 100 impulse shock waves treatment, up-regulation of proliferating cell nuclear antigen (PCNA) (at 6 and 24 h) and collagen type I, collagen type III and TGF-beta1 gene expression (at 24 h) were observed; these were followed by the increases in NO production (at 24 h), TGF-beta1 release (at 48 and 96 h) and collagen synthesis (at the 7th day). This study revealed that shock waves can stimulate tenocyte proliferation and collagen synthesis. The associated tenocyte proliferation is mediated by early up-regulation of PCNA and TGF-beta1 gene expression, endogenous NO release and synthesis and TGF-beta1 protein and then collagen synthesis.


Assuntos
Tendão do Calcâneo/citologia , Matriz Extracelular/efeitos da radiação , Ondas de Choque de Alta Energia/uso terapêutico , Cicatrização/efeitos da radiação , Tendão do Calcâneo/efeitos da radiação , Animais , Biomarcadores/análise , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo III/genética , Colágeno Tipo III/metabolismo , Matriz Extracelular/metabolismo , Expressão Gênica/efeitos da radiação , Masculino , Nitritos/metabolismo , Antígeno Nuclear de Célula em Proliferação/análise , Antígeno Nuclear de Célula em Proliferação/genética , RNA/análise , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
4.
Artif Organs ; 32(2): 167-74, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18269355

RESUMO

Metal pins used to apply skeletal traction or external fixation devices protruding through skin are susceptible to the increased incidence of pin site infection. In this work, we tried to establish the photokilling effects of titanium dioxide (TiO2) nanoparticles on an orthopedic implant with an in vitro study. In these photocatalytic experiments, aqueous TiO2 was added to the tested microorganism. The time effect of TiO2 photoactivation was evaluated, and the loss of viability of five different bacteria suspensions (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus hirae, and Bacteroides fragilis) was examined by the viable count procedure. The bactericidal effect of TiO2 nanoparticle-coated metal plates was also tested. The ultraviolet (UV) dosage used in this experiment did not affect the viability of bacteria, and all bacteria survived well in the absence of TiO2 nanoparticles. The survival curve of microorganisms in the presence of TiO2 nanoparticles showed that nearly complete killing was achieved after 50 min of UV illumination. The formation of bacterial colonies above the TiO2 nanoparticle-coated metal plates also decreased significantly. In this study, we clearly demonstrated the bactericidal effects of titanium dioxide nanoparticles. In the presence of UV light, the titanium dioxide nanoparticles can be applicable to medical facilities where the potential for infection should be controlled.


Assuntos
Antibacterianos/farmacologia , Pinos Ortopédicos/microbiologia , Materiais Revestidos Biocompatíveis/farmacologia , Fármacos Fotossensibilizantes , Titânio/farmacologia , Bacteroides fragilis/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Contagem de Colônia Microbiana , Enterococcus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fixadores Externos , Humanos , Nanopartículas Metálicas , Infecções Relacionadas à Prótese/prevenção & controle , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Raios Ultravioleta
5.
PLoS One ; 8(7): e68662, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23874710

RESUMO

BACKGROUND: Mounting evidence supports the use of laparoscopic techniques for the treatment of simple appendicitis. However, most of the advantages of these techniques are of limited clinical relevance. This study compares the treatment outcomes of laparoscopic appendectomies and open appendectomies performed in Taiwan. METHODS: This study uses data from the 2007 to 2009 Taiwan National Health Insurance Research Database. The study sample included 65,339 patients, hospitalized with a discharge diagnosis of acute appendicitis (33.8% underwent laparoscopic appendectomy). A generalized estimated equation (GEE) was performed to explore the relationship between the use of laparoscopy and 30-day re-admission. Hierarchical linear regressions were performed to examine the relationship between the use of laparoscopy, the length of stay (LOS), and the cost per discharge. RESULTS: A significantly lower proportion of patients undergoing laparoscopic appendectomies were re-admitted within 30 days of their index appendectomy, in comparison to patients undergoing open appendectomies (0.66% versus 1.925, p<0.001). Compared with patients undergoing open appendectomies, patients undergoing laparoscopic appendectomies had a shorter LOS (4.01 versus 5.33 days, p<0.001) and a higher cost per discharge (NT$40,554 versus NT$38,509, p<0.001. In 2007, the average exchange rate was US$1=NT$31.0). GEE revealed that the odds ratio of 30-day readmission for patients undergoing laparoscopic appendectomy was 0.38 (95% CI=0.33-0.46) that of patients undergoing open appendectomies, after adjusting for surgeon, hospital, and patient characteristics, as well as for the clustering effect of particular surgeons and the propensity score. CONCLUSION: This study found that laparoscopic appendectomies had a lower 30-day re-admission rate, and a shorter LOS, but a slightly higher cost per discharge than open appendectomies.


Assuntos
Apendicectomia , Laparoscopia , Doença Aguda , Adulto , Apendicectomia/economia , Apendicectomia/estatística & dados numéricos , Apendicite/economia , Apendicite/epidemiologia , Apendicite/cirurgia , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Laparoscopia/economia , Laparoscopia/estatística & dados numéricos , Tempo de Internação/economia , Tempo de Internação/estatística & dados numéricos , Masculino , Alta do Paciente/economia , Alta do Paciente/estatística & dados numéricos , Readmissão do Paciente/economia , Readmissão do Paciente/estatística & dados numéricos , Médicos/estatística & dados numéricos , Taiwan/epidemiologia , Resultado do Tratamento
6.
Dig Dis Sci ; 53(2): 556-63, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17676395

RESUMO

Cholestasis occurs in a wide variety of human liver diseases, and hepatocellular injury is an invariant feature of cholestasis causing liver dysfunction and inflammation, promoting fibrogenesis, and ultimately leading to liver failure. alpha-Melanocyte-stimulating hormone (alpha-MSH) is a potent anti-inflammatory agent in many models of inflammation, suggesting that it inhibits a critical step common to different forms of inflammation. The aim of this study was to investigate whether the gene transfer of alpha-MSH could attenuate hepatic inflammation after bile duct ligation in the rat. Studies were performed in bile duct-ligated (BDL) rats. Hydrodynamic-based gene transfection with alpha-MSH plasmid via rapid tail vein injection was performed 30 min after ligation of bile duct. The endpoints were studied as markers of inflammation 7 days after bile duct ligation. alpha-MSH expression in liver via a single administration of naked plasmid was demonstrated. Liver inflammation index, including neutrophil infiltration and serum alanine aminotransferase, were significantly reduced in alpha-MSH gene transfer rats. Markers for liver inflammation, including expression of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and inducible NO synthase (iNOS) mRNA, as assessed by real-time PCR, were also attenuated by alpha-MSH gene therapy. Expression of iNOS protein in liver diminished after alpha-MSH gene transfer. Consistent with these data, hepatic stellate cells (HSC) and Kupffer cells were markedly inhibited in alpha-MSH gene-treated rats. Our findings show that gene transfer of alpha-MSH could attenuate hepatic inflammation after bile duct ligation in the rat.


Assuntos
Colestase Extra-Hepática/tratamento farmacológico , Terapia Genética , alfa-MSH/uso terapêutico , Alanina Transaminase/sangue , Animais , Colestase Extra-Hepática/metabolismo , Colestase Extra-Hepática/patologia , Ducto Colédoco/cirurgia , Técnicas de Transferência de Genes , Imuno-Histoquímica , Interleucina-1beta/sangue , Células de Kupffer/metabolismo , Ligadura , Masculino , Neutrófilos/metabolismo , Óxido Nítrico Sintase Tipo II/sangue , Plasmídeos , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/sangue , alfa-MSH/genética , alfa-MSH/metabolismo
7.
J Orthop Surg Res ; 3: 12, 2008 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-18312690

RESUMO

Soy protein, a rich source of phytoestrogens, exhibit estrogen-type bioactivity. The purpose of this study was to determine if ingestion of isoflavones before ovariectomy can prevent bone loss following ovariectomy. Twenty-four nulliparous Wistar rats were randomly divided into four groups. In the normal diet groups, a sham operation was performed on Group A, while ovariectomy was performed on Group B. For Groups C and D, all rats were fed with an isoflavone-rich (25 mg/day) diet for one month, then bilateral ovariectomy were performed. In the rats in Group C, a normal diet was begun following the ovariectomy. The rats in Groups D continued to receive the isoflavone-rich diet for two additional months postoperatively. All rats were sacrificed 60 days after surgery. The weight of bone ash of the long bones and whole lumbar spine were determined. A histological study of cancellous bone was done and biochemical indices of skeletal metabolism were performed and analyzed. The markers of bone metabolism exhibited no significant changes. When compared with the sham-operated rats fed a normal diet, the bone mass of ovariectomized rats decreased significantly; pre-ovariectomy ingestion of an isoflavone-rich diet did not prevent bone loss. The bone mass of rats treated with an isoflavone-rich diet for three months was higher than controls two months after ovariectomy. Dietary isoflavones did not prevent the development of post-ovariectomy bone loss, but long-term ingestion of an isoflavone-rich diet increased the bone mineral contents after ovariectomy in young rats.

8.
J Orthop Surg Res ; 2: 13, 2007 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-17711591

RESUMO

BACKGROUND AND PURPOSE: Intensive eccentric exercise can cause muscle damage. We simulated an animal model of isokinetic eccentric exercise by repetitively stretching stimulated triceps surae muscle-tendon units to determine if such exercise affects the mechanical properties of the unit within its physiologic excursion. METHODS: Biomechanical parameters of the muscle-tendon unit were monitored during isokinetic eccentric loading in 12 rabbits. In each animal, one limb (control group) was stretched until failure. The other limb (study group) was first subjected to isokinetic and eccentric cyclic loading at the rate of 10.0 cm/min to 112% (group I) or 120% (group II) of its initial length for 1 hour and then stretched to failure. Load-deformation curves and biomechanical parameters were compared between the study and control groups. RESULTS: When the muscle-tendon unit received eccentric cyclic loading to 112%, changes in all biomechanical parameters - except for the slope of the load-deformation curve - were not significant. In contrast, most parameters, including the slope of the load-deformation curve, peak load, deformation at peak load, total energy absorption, and energy absorption before peak load, significantly decreased after isokinetic eccentric cyclic loading to 120%. CONCLUSION: We found a threshold for eccentrically induced injury of the rabbit triceps surae muscle at between 12% and 20% strain, which is within the physiologic excursion of the muscle-tendon units. Our study provided evidence that eccentric exercise may induce changes in the biomechanical properties of skeletal muscles, even within the physiologic range of the excursion of the muscle-tendon unit.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA