RESUMO
The intraoral vertical ramus osteotomy (IVRO) is a useful technique for mandibular setback surgery. However, there is a tendency for lateral flaring of the proximal segments on the non-deviation side after the correction of mandibular asymmetry with this technique. The purpose of this retrospective study was to evaluate the positional changes of the proximal segments after IVRO setback in skeletal class III patients with asymmetry, using preoperative and postoperative computed tomography scan data, and to apply the results in clinical practice. A total of 28 skeletal class III patients with asymmetry who underwent bimaxillary orthognathic surgery were included. A three-dimensional cone beam computed tomography scan was obtained preoperative, at 1month postoperative, and at 1year postoperative. At 1month after the surgery, the proximal segments showed an outward rotation, lateral flaring, and anterior rotation of the condylar head. All postsurgical directional changes had returned to the preoperative state at 1year postoperative, and there was no statistically significant difference in postoperative angulation changes between the two sides. The results showed no statistical differences in the positional changes of the proximal segments between the deviation and non-deviation sides. This study reaffirms the benefits of the IVRO for a minimal bony interference between the proximal and distal segments in three dimensions, including mandibular asymmetry cases.
Assuntos
Procedimentos Cirúrgicos Ortognáticos , Prognatismo , Cefalometria , Assimetria Facial , Humanos , Mandíbula , Osteotomia Sagital do Ramo Mandibular , Estudos RetrospectivosRESUMO
BACKGROUND: Abdominal wall hernias are common in patients with ascites. Elective surgical repair is recommended for the treatment of abdominal wall hernias. However, surgical hernia repair in cirrhotic patients with refractory ascites is controversial. In this study, we aimed to evaluate the outcomes of elective surgical hernia repair in patients with liver cirrhosis with and without refractory ascites. METHOD: From January 2005 to June 2018, we retrospectively reviewed the records of consecutive patients with liver cirrhosis who underwent a surgical hernia repair. RESULTS: This study included 107 patients; 31 patients (29.0%) had refractory ascites. Preoperatively, cirrhotic patients with refractory ascites had a higher median model for end-stage liver disease (MELD) score (13.0 vs 11.0, P = 0.001) than those without refractory ascites. The 30-day mortality rate (3.2% vs 0%, P = 0.64) and the risk of recurrence (hazard ratio 0.410; 95% CI 0.050-3.220; P = 0.39) did not differ significantly between cirrhotic patients with refractory ascites and cirrhotic patients without refractory ascites. Among cirrhotic patients with refractory ascites, albumin (P = 0.23), bilirubin (P = 0.37), creatinine (P = 0.97), and sodium levels (P = 0.35) did not change significantly after surgery. CONCLUSION: In advanced liver cirrhosis patients with refractory ascites, hernias can be safely treated with elective surgical repair. Mortality rate within 30 days did not differ by the presence or absence of refractory ascites. Elective hernia repair might be beneficial for treatment of abdominal wall hernia in cirrhotic patients with refractory ascites.
Assuntos
Ascite , Hérnia Ventral/cirurgia , Herniorrafia , Cirrose Hepática , Idoso , Ascite/etiologia , Ascite/mortalidade , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Feminino , Hérnia Ventral/complicações , Hérnia Ventral/mortalidade , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Herniorrafia/mortalidade , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Estudos Retrospectivos , Telas Cirúrgicas , Resultado do TratamentoRESUMO
Endochondral ossification during long bone development and natural fracture healing initiates by mesenchymal cell condensation, directed by local morphogen signals and mechanical cues. Here, we aimed to mimic development for regeneration of large bone defects. We hypothesized that engineered human mesenchymal condensations presenting transforming growth factor-ß1 (TGF-ß1) and/or bone morphogenetic protein-2 (BMP-2) from encapsulated microparticles promotes endochondral defect regeneration contingent on in vivo mechanical cues. Mesenchymal condensations induced bone formation dependent on morphogen presentation, with BMP-2 + TGF-ß1 fully restoring mechanical function. Delayed in vivo ambulatory loading significantly enhanced the bone formation rate in the dual morphogen group. In vitro, BMP-2 or BMP-2 + TGF-ß1 initiated robust endochondral lineage commitment. In vivo, however, extensive cartilage formation was evident predominantly in the BMP-2 + TGF-ß1 group, enhanced by mechanical loading. Together, this study demonstrates a biomimetic template for recapitulating developmental morphogenic and mechanical cues in vivo for tissue engineering.
Assuntos
Desenvolvimento Ósseo/fisiologia , Osso e Ossos/fisiologia , Morfogênese/fisiologia , Osteogênese/fisiologia , Animais , Biomimética/métodos , Osso e Ossos/metabolismo , Células Cultivadas , Humanos , Masculino , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/fisiologia , Ratos , Engenharia Tecidual , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismoRESUMO
BACKGROUND: There have been conflicting results about the association between Behçet's disease and smoking. Smoking has been reported to be a protective factor for Behçet's disease, whereas smoking may have a role in triggering Behçet's disease. OBJECTIVES: The aim of this study was to investigate the incidence of Behçet's disease in Korea according to smoking status using nationwide population data. METHODS: We analysed clinical data from individuals 20 years of age and older who received a health examination arranged by the Korean national insurance programme between 2009 and 2012. The incidence of Behçet's disease was analysed according to smoking status reported by individuals during their health examination. Newly diagnosed cases of Behçet's disease were identified using claims data from baseline to the date of diagnosis or until 31 December 2016. RESULTS: The risk of Behçet's disease was lower in current smokers compared with never-smokers regardless of the amount and duration of smoking. The decreased risk of Behçet's disease in current smoker persisted after adjusting for age, sex, regular exercise, drinking status, BMI, diabetes mellitus, hypertension, and dyslipidaemia, history of stroke and/or history of ischaemic heart diseases. LIMITATIONS: Genetic susceptibility or family history of Behçet's disease was not considered. CONCLUSIONS: This study found a decreased incidence of Behçet's disease in current smokers compared with never-smokers. Further investigation of the pathophysiology responsible for the negative association between smoking and Behçet's disease is needed.
Assuntos
Síndrome de Behçet/epidemiologia , Fumar/epidemiologia , Adulto , Idoso , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Adulto JovemRESUMO
Aims: The aim of this study was to compare the rate of mortality and causes of death in Korean patients who undergo surgery for a fracture of the hip, up to 11 years after the injury, with a control group from the general population. Materials and Methods: National cohort data from Korean Health Insurance Review and Assessment Service - National Sample Cohort were used. A ratio of 1:4 matched patients with a fracture who underwent surgery (3383, fracture group) between 2003 and 2012, and controls (13 532) were included. The matches were processed for age, gender, income, and region of residence. We also undertook analyses of subgroups according to age and gender. The mean follow-up was 4.45 years (1 to 11). Results: The prevalence of hypertension, diabetes, and stroke was significantly higher in the fracture group and dyslipidemia in the controls. Both crude and adjusted hazard ratios (HR) for the rate of mortality in the fracture group were > 2 (crude HR 2.03, 95% confidence interval (CI) 1.91 to 2.17, p < 0.001; adjusted HR 2.07, 95% CI 1.94 to 2.21, p < 0.001). The HRs were also > 2 for both men and women, and for both those aged ≥ 50 years and < 50 years. However, for those aged < 50 years, they were insignificant. The rates of mortality due to all 11 major causes of death classified following Korean standard classification of diseases were significantly higher in the fracture group compared with the control group, except those in the mental and behavioral disorders category. Conclusion: The rate of mortality in the fracture group was significantly higher than in the control group up to 11 years after the surgery. The rate of death due to almost every major cause was significantly higher in the fracture group compared with the control group. Cite this article: Bone Joint J 2018;100-B:436-42.
Assuntos
Fraturas do Quadril/mortalidade , Fraturas do Quadril/cirurgia , Complicações Pós-Operatórias/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Modelos de Riscos Proporcionais , República da Coreia/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Rifaximin might decrease the risk of portal hypertension-related complications by controlling small intestinal bacterial overgrowth. AIM: To evaluate whether rifaximin was associated with the risk of death and cirrhotic complications. METHODS: We conducted a retrospective study that included 1042 patients experiencing hepatic encephalopathy (HE): 421 patients without hepatocellular carcinoma (HCC; the non-HCC cohort) and 621 patients with HCC (the HCC cohort). The primary endpoint was overall survival and secondary endpoints were recurrence of HE and the development of spontaneous bacterial peritonitis (SBP), hepatorenal syndrome (HRS) and variceal bleeding. RESULTS: In the non-HCC cohort, 145 patients received rifaximin plus lactulose (the rifaximin group) and 276 patients received lactulose alone (the control group). The multivariate analysis revealed that rifaximin was significantly associated with lower risk of death (adjusted hazard ratio [aHR], 0.697; P = .024) and reduced the risk of recurrent HE (aHR, 0.452; P < .001), SBP (aHR, 0.210; P < .001) and variceal bleeding (aHR, 0.425; P = .011) but not HRS (aHR, 0.598; P = .08). In the HCC cohort, 173 patients received rifaximin plus lactulose and 448 patients received lactulose. Rifaximin was not associated with the risk of death (aHR, 1.177; P = .121). Rifaximin was associated with lower risk of SBP (aHR, 0.323; P < .001) but not with variceal bleeding (aHR, 0.660; P = .104) or recurrent HE (aHR, 0.689; P = .057). The risk of Clostridium difficile-associated diarrhoea was not different between the groups (aHR, 0.028; P = .338). CONCLUSIONS: In patients without HCC, rifaximin treatment was significantly associated with prolonged overall survival and reduced risks of spontaneous bacterial peritonitis, variceal bleeding and recurrent hepatic encephalopathy.
Assuntos
Anti-Infecciosos/uso terapêutico , Encefalopatia Hepática/tratamento farmacológico , Rifamicinas/uso terapêutico , Idoso , Infecções Bacterianas/prevenção & controle , Carcinoma Hepatocelular/tratamento farmacológico , Varizes Esofágicas e Gástricas/prevenção & controle , Feminino , Encefalopatia Hepática/complicações , Humanos , Lactulose/uso terapêutico , Cirrose Hepática/etiologia , Neoplasias Hepáticas/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Peritonite/prevenção & controle , Recidiva , Estudos Retrospectivos , Rifaximina , Prevenção SecundáriaRESUMO
Mandibular step osteotomy is a useful technique for large mandibular setbacks. We report a case of a patient who had a mandibular step osteotomy using a CAD/CAM-derived wafer for mandibular setback with reduction of the arch.
Assuntos
Osteotomia Mandibular/métodos , Prognatismo/cirurgia , Contenções , Adulto , Cefalometria , Desenho Assistido por Computador , Humanos , Imageamento Tridimensional , Masculino , Prognatismo/diagnóstico por imagemRESUMO
UNLABELLED: Quercetin is a flavonol believed to have beneficial effects on human health. Rutin, found in many plants, fruits and vegetables, is metabolized by human intestinal bacteria and converted to quercetin, where it is absorbed through the intestinal epithelium. This study aimed to isolate and characterize human intestinal bacteria capable of converting rutin to quercetin. A bacterium that can metabolize rutin was isolated from human faecal samples and identified by 16S rRNA gene sequencing. The whole-cell enzymatic activities on flavonoid glycoside and the conversion profiles of the isolate were also analysed. The bacterium was identified as Enterococcus avium EFEL009 and was shown to convert rutin to isoquercetin and then to quercetin under anaerobic conditions. Microscopic analysis revealed short chains of cocci with diameters of approx. 1 µm. ß-Glucosidase was shown to be constitutively expressed in Ent. avium, while α-rhamnosidase was expressed following induction by rutin. Both enzymes were mainly localized to the cell surface. This study is the first report on the isolation of a quercetin-producing Ent. avium FEEL009, which could be a potential industrial starter bacterium. SIGNIFICANCE AND IMPACT OF THE STUDY: Quercetin is a member of the flavonoids family reported to have better cytoprotective abilities, stronger inhibition of lipopolysaccharide-induced nitric oxide production, and better chemoprevention than rutin. This is the first report on the isolation and characterization of Enterococcus avium EFEL009 from the human intestine which is capable of converting rutin to quercetin.
Assuntos
Enterococcus/isolamento & purificação , Enterococcus/metabolismo , Intestinos/microbiologia , Quercetina/biossíntese , Rutina/metabolismo , Quimioprevenção , Fezes/microbiologia , Flavonoides/metabolismo , Glicosídeo Hidrolases/biossíntese , Glicosídeos/metabolismo , Humanos , Lipopolissacarídeos , Dados de Sequência Molecular , Óxido Nítrico/biossíntese , Quercetina/farmacologia , RNA Ribossômico 16S/genética , beta-Glucosidase/biossínteseRESUMO
The anti-apoptotic effects of heat-shock protein (Hsp70) were assessed in SCG neurones following nerve growth factor (NGF) withdrawal. The results showed that the virally mediated expression of Hsp70 mirrored the effects of the c-Jun-N-terminal kinase (JNK) binding domain (JBD) of JNK interacting protein (an inhibitor of JNK and c-Jun activation) and suppressed the phosphorylation of c-Jun. Preventing c-Jun transcriptional activity subsequently led to reduced cytochrome c release and prevented caspase activation as indicated by a decrease in poly (ADP-ribose) polymerase-1 (PARP) cleavage. Together, these results show that Hsp70 is a highly effective inhibitor of apoptosis in sympathetic neurones and that it mediates this effect primarily by suppressing c-Jun transcriptional signalling.
Assuntos
Apoptose/fisiologia , Proteínas de Choque Térmico HSP70/metabolismo , Neurônios/fisiologia , Proteínas Proto-Oncogênicas c-jun/metabolismo , Gânglio Cervical Superior/citologia , Animais , Animais Recém-Nascidos , Sobrevivência Celular , Células Cultivadas , Citocromos c/metabolismo , Ativação Enzimática , Proteínas de Fluorescência Verde/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Mitocôndrias/metabolismo , Fator de Crescimento Neural/metabolismo , Pirofosfatases/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/fisiologia , Transfecção/métodosRESUMO
We studied the ability of heat shock, DnaJ-like-1 (HSJ1) proteins (which contain DnaJ and ubiquitin-interacting motifs) to reduce polyglutamine-mediated inclusion formation. The experiments demonstrated that expression of heat shock protein 70 (hsp70), hsp40, HSJ1a, and HSJ1b significantly reduced protein inclusion formation in a model of spinal and bulbar muscular atrophy (SBMA). HSJ1a also mediated a significant decrease in the number of inclusions formed in a primary neuronal model of protein aggregation. Studies to elucidate the mechanisms underlying these reductions showed that hsp70 and hsp40 increased chaperone-mediated refolding. In contrast, expression of HSJ1 proteins did not promote chaperone activity but caused an increase in ubiquitylation. Furthermore, HSJ1a was associated with a ubiquitylated luciferase complex, and in the presence of HSJ1a but not an HSJ1a UIM mutant (HSJ1a-deltaUIM) there was a reduction in luciferase protein levels. Together these results show that HSJ1 proteins mediated an increase in target protein degradation via the ubiquitin-proteasome system (UPS). We also found that the expression of HSJ1a significantly decreased the number of neurons containing inclusions in an in vivo model of polyglutamine disease. These findings indicate that targeted modification of the UPS to facilitate degradation of misfolded proteins may represent a highly effective therapeutic avenue for the treatment of polyglutamine disease.
Assuntos
Proteínas de Choque Térmico HSP40/genética , Corpos de Inclusão/metabolismo , Atrofia Muscular Espinal/terapia , Peptídeos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Células Cultivadas , Dependovirus/genética , Vetores Genéticos/genética , Proteínas de Choque Térmico HSP40/fisiologia , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/fisiologia , Imuno-Histoquímica , Imunoprecipitação , Luciferases/química , Luciferases/genética , Luciferases/metabolismo , Masculino , Microscopia de Fluorescência , Atrofia Muscular Espinal/metabolismo , Atrofia Muscular Espinal/patologia , Neurônios/metabolismo , Peptídeos/genética , Dobramento de Proteína , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Receptores Androgênicos/genética , Receptores Androgênicos/fisiologia , TransfecçãoRESUMO
Calcium sulfite hemihydrate (CaSO(3).0.5H2O), a common byproduct of coal-fired utilities, is fairly insoluble and can decompose to release toxic SO2 under highly acidic soil conditions; however, it can also oxidize to form gypsum. The objective of this study was to examine the effects of application rate and soil pH on the oxidation of calcium sulfite under laboratory conditions. Oxidation rates measured by release of SO4-S to solution decreased with increasing application rate. Leachate SO4-S from soils amended with 1.0 to 3.0 g kg-1 CaSO3 increased over a 21 to 28 d period before reaching a plateau. At 4 g kg-1, maximum SO4-S release was delayed until Week 7. Oxidation and release of SO4-S from soil amended with 3.0 g kg-1 calcium sulfite increased markedly with decreasing soil pH. After only 3 d incubation, the concentrations of SO4-S in aqueous leachates were 77, 122, 170, 220, and 229 mg L-1 for initial soil pH values of 7.8, 6.5, 5.5, 5.1, and 4.0, respectively. At an initial soil pH value of 4.0, oxidation/dissolution did not increase much after 3 d. At higher pH values, oxidation was maximized after 21 d. These results suggest that autumn surface applications of calcium sulfite in no-till systems should permit ample time for oxidation/dissolution reactions to occur without introducing biocidal effects related to oxygen scavenging. Soil and annual crops can thus benefit from additions of soluble Ca and SO4 if calcium sulfite is applied in advance of spring planting.
Assuntos
Cálcio/química , Gases/química , Solo , Sulfitos/química , Enxofre/química , Concentração de Íons de Hidrogênio , OxirreduçãoRESUMO
Maternally inherited mitochondrial DNA (mtDNA) has been suggested to be a genetic factor for diabetes. Reports have shown a decrease of mtDNA content in tissues of diabetic patients. We investigated the effects of mtDNA depletion on glucose metabolism by use of rho(0) SK-Hep1 human hepatoma cells, whose mtDNA was depleted by long-term exposure to ethidium bromide. The rho(0) cells failed to hyperpolarize mitochondrial membrane potential in response to glucose stimulation. Intracellular ATP content, glucose-stimulated ATP production, glucose uptake, steady-state mRNA and protein levels of glucose transporters, and cellular activities of glucose-metabolizing enzymes were decreased in rho(0) cells compared with parental rho(+) cells. Our results suggest that the quantitative reduction of mtDNA may suppress the expression of nuclear DNA-encoded glucose transporters and enzymes of glucose metabolism. Thus this may lead to diabetic status, such as decreased ATP production and glucose utilization.
Assuntos
DNA Mitocondrial/metabolismo , Glucose/farmacocinética , Proteínas de Transporte de Monossacarídeos/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Carcinoma Hepatocelular , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Inibidores Enzimáticos/farmacologia , Etídio/farmacologia , Glucosefosfato Desidrogenase/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Neoplasias Hepáticas , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Proteínas de Transporte de Monossacarídeos/genética , Células Tumorais CultivadasRESUMO
Eudragit microspheres, to float in the gastrointestinal tract, were prepared to prolong a gastrointestinal transit time. To enhance their buoyancy, non-volatile oil was added to the dispersed phase. When an oil component was not miscible with water, over 90% was entrapped within the microspheres and prolonged the floating time of the microspheres. Depending on the solvent ratio, the morphologies of the microspheres were different and the best result was obtained when the ratio of dichloromethane:ethanol:isopropanol was 5:6:4. As the isopropanol portion increased, the time to form microspheres was delayed and the amount of fibre-like substance produced was decreased, due to the slow diffusion rate of the solvent. Compared with microspheres prepared without non-volatile oil, the release rate of the drug from microspheres was faster in all cases tested, except the microspheres containing mineral oil. The solubility of the drug in the non-volatile oil affected the release profiles of the drugs. The non-volatile oil tends to decrease the glass transition temperature of prepared microspheres and change the release profile. The internal morphology of the microspheres was slightly different depending on the entrapped oil phase used. Tiny spherical objects were present at the inner surface of microspheres and the inside of the shell.
Assuntos
Emulsões , Excipientes/química , Microesferas , Óleos/química , Acrilatos/química , Cromatografia Líquida de Alta Pressão , Análise Diferencial Térmica , Difusão , Microscopia Eletrônica de Varredura , Óleo Mineral/química , Miristatos/química , Tamanho da Partícula , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/análise , SolventesRESUMO
BACKGROUND AND OBJECTIVES: To identify risk factors for intraocular pressure (IOP) increases during hemodialysis (HD) in the early postoperative period following pars plana vitrectomy (PPV). PATIENTS AND METHODS: Comparisons of 36 vitrectomized eyes of 22 diabetics undergoing maintenance HD with those of 138 eyes of 69 nonoperated patients. Serial IOPs were measured before PPV, after PPV/before dialysis, and during dialysis. Serum osmolarity and blood pressure were also recorded. RESULTS: In 20 of 36 operated eyes (55.6%) and 18 of 138 nonoperated eyes (13.0%) IOP was increased (> or =4 mm Hg) during HD. In the operated group, marked increases (> or =7 mm Hg) were noted in 9 eyes and ocular pain in 5 eyes. Eyes with pre-existing outflow obstruction and/or acute postoperative outflow compromise carried high risks. No correlation with changes in serum osmolarity or blood pressure was found. CONCLUSION: Monitoring of IOP during HD seems warranted when diabetics with pre-existing outflow obstruction and/or postoperative outflow compromise, undergo HD following PPV.
Assuntos
Pressão Intraocular , Falência Renal Crônica/terapia , Hipertensão Ocular/etiologia , Complicações Pós-Operatórias , Diálise Renal/efeitos adversos , Vitrectomia , Hemorragia Vítrea/cirurgia , Adulto , Idoso , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/terapia , Feminino , Humanos , Pressão Intraocular/fisiologia , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Hipertensão Ocular/fisiopatologia , Descolamento Retiniano/complicações , Descolamento Retiniano/fisiopatologia , Descolamento Retiniano/cirurgia , Fatores de Risco , Hemorragia Vítrea/complicações , Hemorragia Vítrea/fisiopatologiaRESUMO
We investigated whether S-adenosylmethionine (SAM) treatment improved ischemic injury using perfused rat liver after sequential periods of 24 h cold and 20 min re-warming ischemia. SAM (100 micromol/L) was added to University of Wisconsin (UW) solution and Ringers lactate solution. After cold and sequential warm ischemia, releases of lactate dehydrogenase (LDH) and purine nucleoside phosphorylase (PNP) markedly increased during reperfusion. The increase in PNP was significantly reduced by SAM treatment. While the concentration of reduced glutathione (GSH) in ischemic livers significantly decreased, the concentration of glutathione disulfide (GSSG) increased. This decrease in GSH and increase in GSSG were suppressed by SAM treatment. Lipid peroxidation was elevated in cold and warm ischemic and reperfused livers, but this elevation was also prevented by SAM treatment. Hepatic ATP levels were decreased in the ischemic and reperfused livers to 42% of the control levels. However, treatment with SAM resulted in significantly higher ATP levels and preserved the concentration of AMP in ischemic livers. Our findings suggest that SAM prevents oxidative stress and lipid peroxidation and helps preserve hepatic energy metabolism.
Assuntos
Isquemia/tratamento farmacológico , Fígado/irrigação sanguínea , S-Adenosilmetionina/farmacologia , Trifosfato de Adenosina/análise , Animais , Metabolismo Energético/efeitos dos fármacos , Glutationa/metabolismo , Isquemia/metabolismo , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
We investigated the role of tumor necrosis factor (TNF)-alpha in the onset of neuronal and glial apoptosis after traumatic spinal cord crush injury in rats. A few TUNEL-positive cells were first observed within and surrounding the lesion area 4 h after injury, with the largest number observed 24-48 h after injury. Double-labeling of cells using cell type-specific markers revealed that TUNEL-positive cells were either neurons or oligodendrocytes. One hour after injury, an intense immunoreactivity to TNF-alpha was observed in neurons and glial cells in the lesion area, but also seen in cells several mm from the lesion site rostrally and caudally. The level of nitric oxide (NO) also significantly increased in the spinal cord 4 h after injury. The injection of a neutralizing antibody against TNF-alpha into the lesion site several min after injury significantly reduced both the level of NO observed 4 h thereafter as well as the number of apoptotic cells observed 24 h after spinal cord trauma. An inhibitor of nitric oxide synthase (NOS), N(G)-monomethyl-l-arginine acetate (l-NMMA), also reduced the number of apoptotic cells. This reduction of apoptotic cells was associated with a decrease in DNA laddering on agarose gel electrophoresis. These results suggest that: (i) TNF-alpha may function as an external signal initiating apoptosis in neurons and oligodendrocytes after spinal cord injury; and (ii) TNF-alpha-initiated apoptosis may be mediated in part by NO as produced by a NOS expressed in response to TNF-alpha.
Assuntos
Apoptose/fisiologia , Degeneração Neural/fisiopatologia , Neuroglia/metabolismo , Traumatismos da Medula Espinal/fisiopatologia , Fator de Necrose Tumoral alfa/metabolismo , Animais , Marcação In Situ das Extremidades Cortadas , Masculino , Degeneração Neural/imunologia , Degeneração Neural/patologia , Neuroglia/imunologia , Neuroglia/patologia , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Traumatismos da Medula Espinal/imunologia , Traumatismos da Medula Espinal/patologia , Fator de Necrose Tumoral alfa/imunologiaRESUMO
In the vertebrate central nervous system (CNS), tumour necrosis factor-alpha (TNF-alpha) is produced by astrocytes and microglia and mediates cell injury in nerve cells and oligodendrocytes. In the present study, we have used a specific inhibitor of p38 MAP kinase, SB203580 to examine the role of p38 MAP kinase in regulation of TNF-alpha production in human astrocytes and microglia in terms of levels of mRNA and secreted protein. A reverse transcriptase polymerase chain reaction (RT-PCR) analysis showed that increased levels of TNF-alpha mRNA were induced in astrocytes by IL-1beta treatment, and in microglia by bacterial lipopolysaccharide (LPS). In microglia, treatment with SB203580 reduced the level of TNF-alpha mRNA, but in astrocytes it did not. However, the secretion of TNF-alpha by both astrocytes and microglia was markedly inhibited by SB203580 at a low concentration. TNF-alpha secretion was reduced approximately 80% in astrocytes and 85% in microglia. The results demonstrate a key role played by p38 MAP kinase in upregulation of TNF-alpha mRNA levels in LPS-activated human microglia, whereas p38 MAP kinase is involved in post-transcriptional regulation of TNF-alpha production at translational level in IL-1beta-activated human astrocytes.
Assuntos
Astrócitos/metabolismo , Microglia/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Células Cultivadas , Inibidores Enzimáticos/farmacologia , Humanos , Imidazóis/farmacologia , Interleucina-1/farmacologia , Lipopolissacarídeos/farmacologia , Microglia/citologia , Microglia/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Piridinas/farmacologia , RNA Mensageiro/metabolismo , Fator de Necrose Tumoral alfa/genética , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
In higher vertebrates, reactive gliosis resulting from injury to the central nervous system (CNS) is characterized by a rapid increase in immunoreactivity (IR) to glial fibrillary acidic protein (GFAP). Little is known about the extracellular signals that initiate the increase in GFAP-IR following CNS injury. We demonstrated recently [T.H. Oh, G.J. Markelonis, J.R. Von Visger, B. Baik, M.T. Shipley, Acidic pH rapidly increases immunoreactivity of glial fibrillary acidic protein in cultured astrocytes, Glia 13 (1995) 319-322] that a rapid increase in GFAP-IR can be evoked in mature astrocyte cultures by exposing the cells to an acidic medium. We investigated the intracellular pathway(s) involved in initiating increased GFAP-IR, a hallmark of reactive astrocytes. The increase in GFAP-IR produced by exposure to acidic medium was blocked by pretreatment with nickel ions, by such blockers of L-type calcium channels as nifedipine, verapamil and diltiazem, by calpain inhibitor I, or by the intracellular calcium chelator, BAPTA-AM. At physiological pH, treatment with the calcium ionophore, A23187, resulted in increased GFAP-IR which could be blocked by pretreatment with calpain inhibitor I. Astrocytes exposed to low pH exhibited a marked increase in a GFAP fragment with a molecular weight of 48 kDa. In astrocytes exposed to acidic medium, alpha-fodrin, a selective endogenous substrate of calpain, was also found to be hydrolyzed producing fragments with molecular weights of 120-150 kDa. As anticipated, pretreatment with calpain inhibitor I prevented the proteolytic degradation of both GFAP and alpha-fodrin in these samples. These results suggest that the initial increase in GFAP-IR after CNS injury appears to be linked to Ca(++) influx, and is mediated further by a proteolytic process that seemingly involves the activation of the calcium-dependent protease, calpain I.
Assuntos
Ácidos/metabolismo , Astrócitos/enzimologia , Cálcio/metabolismo , Calpaína/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Concentração de Íons de Hidrogênio , Sequência de Aminoácidos , Animais , Anticorpos , Astrócitos/citologia , Astrócitos/imunologia , Calcimicina/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Proteínas de Transporte/metabolismo , Proteínas de Transporte/farmacologia , Células Cultivadas , Quelantes/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Diltiazem/farmacologia , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Ativação Enzimática/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/análise , Proteína Glial Fibrilar Ácida/química , Glicoproteínas/farmacologia , Técnicas In Vitro , Ionóforos/farmacologia , Proteínas dos Microfilamentos/metabolismo , Proteínas dos Microfilamentos/farmacologia , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/farmacologia , Nifedipino/farmacologia , Prosencéfalo/citologia , Ratos , Ratos Endogâmicos F344 , Especificidade por Substrato , Verapamil/farmacologiaRESUMO
The effects of the pro-inflammatory cytokine interleukin-1-beta (IL-1beta) on levels of intracellular calcium [Ca(2+)](i) in cultured human microglia have been studied using the fluorescent Ca(2+) indicator fura-2. IL-1beta (2 ng/ml) caused a slow, progressive increase in [Ca(2+)](i) in standard Ca(2+)-containing physiological solution (PSS). A similar effect was observed in separate studies using Ca(2+)-free PSS, however, the mean rate of increase was significantly lower than that measured with PSS. Similar results were obtained in a separate protocol, where cells were exposed to both IL-1beta in Ca(2+)-free PSS and PSS. The slope of the IL-1beta induced increase of [Ca(2+)](i) in Ca(2+)-free PSS was not altered when adenosine triphosphate was added prior to application of the cytokine. These results suggest that IL-1beta-induced responses in human microglia involve both a Ca(2+) entry pathway and a mechanism of intracellular increase other than from IP(3)-sensitive stores.
Assuntos
Cálcio/metabolismo , Interleucina-1/metabolismo , Microglia/metabolismo , Células Cultivadas , Embrião de Mamíferos , Humanos , Interleucina-1/farmacologia , Microglia/efeitos dos fármacosRESUMO
Prolonged circulation of anticancer agent in blood is expected to decrease the host toxicity and enhance the anticancer activity. The purpose of this study is to develop and characterize the prolonged and sustained release formulation of anticancer agent using biodegradable poly(gamma-benzyl-L-glutamate)/poly(ethylene oxide) (PBLG/PEO) polymer nanoparticles. PBLG/PEO polymer is a hydrophilic/hydrophobic block copolymer and forms a micelle-like structure in solution. Spherical nanoparticles incorporating adriamycin were prepared by a dialysis method. The fluorescence intensity of adriamycin in the nanoparticles was increased when sodium dodecylsulfate was added. It is one of the evidences of entrapment of adriamycin in the polymer nanoparticles. Only 20% of entrapped drug was released in 24 h at 37 degrees C a and the release was dependent on the molecular weight of hydrophobic polymer. The endothermic peak of adriamycin at 197 degrees C disappeared in the nanoparticles system, suggesting the inhibition of a crystallization of adriamycin by polymer adsorption during the precipitation process. The mean residence time of adriamycin from the nanoparticles was more than threefold that from a free adriamycin. These results suggest usefulness of PBLG/PEO nanoparticles as a sustained and prolonged release carrier for adriamycin.