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1.
J Dent Res ; 98(5): 556-563, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30786812

RESUMO

Zirconia (ZrO2) dental implants provide good biocompatibility, have good corrosion resistance, and have a color that is similar to that of natural teeth. Unfortunately, ZrO2 is a bioinert material and therefore achieves osseointegration difficultly. In this study, we sought to enhance osseointegration by producing rough ZrO2 surfaces that contain hydroxyl groups (designated ZSA) through the use of sandblasting in conjunction with alkaline treatment. We immobilized type I collagen on ZSA surfaces using the natural cross-linker, procyanidin. Our results further showed that surfaces produced in ZSA-P/C featured more and steadier type I collagen than surfaces produced in ZSA-C. The ZSA-P/C also presented superior cell responses in terms of adhesion, proliferation, and mineralization of human bone marrow mesenchymal stem cells. The enhanced cell responses in the ZSA-P/C were induced through the prolonged activation of focal adhesion kinase, AKT (the phosphoinositide 3-kinase pathway), and p38 (the mitogen-activated protein kinase pathway). The simple and novel approach to immobilize type I collagen on roughened ZrO2 surfaces presented in this article can likely benefit dental implant applications.


Assuntos
Colágeno Tipo I , Zircônio , Implantes Dentários , Humanos , Osseointegração , Fosfatidilinositol 3-Quinases , Propriedades de Superfície , Titânio
2.
Dis Esophagus ; 29(4): 392-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25715747

RESUMO

Esophagitis is the second most common gastrointestinal manifestation of cytomegalovirus (CMV) infection after colitis. CMV esophagitis has been reported in patients who have undergone transplantation, are on long-term renal dialysis, or who have the human immunodeficiency virus infection. This study aimed to investigate the clinical characteristics and manifestations of CMV esophagitis in patients who underwent diagnostic endoscopy. A total of 16 patients with histologically proven CMV infection were identified from 1539 patients with esophageal ulcers and analyzed retrospectively (January 2006 to December 2013). Patients' personal data (age, smoking, and alcohol consumption), underlying systemic diseases (diabetes mellitus, end-stage renal disease, and chronic obstructive pulmonary disease), malignancy, indication for esophagogastroduodenoscopy, endoscopic characteristics, and diagnostic methods (pathological or serological findings) were collected for further analysis. Among the patients with CMV esophagitis, the mean age was 59.94 years (range, 23-84 years). The male : female ratio was 1.67:1. Odynophagia and epigastralgia were common symptoms. Of the 16 patients, 3 (18.75%) were infected with the human immunodeficiency virus and 9 (56.25%) had an underlying malignancy, including lung cancer (6 patients), esophageal cancer (2 patients), gastric cancer (1 patient), ampulla of Vater cancer (1 patient), and lymphoma (1 patient). Six of the 9 patients (66.7%) with malignancy had been administered concurrent chemoradiotherapy (CCRT). In this study, patients with malignancy who had been administered CCRT were at increased risk for CMV esophagitis, which had not been reported before in the literature. CMV esophagitis should be considered as a potential treatment-related complication of CCRT.


Assuntos
Quimiorradioterapia/efeitos adversos , Infecções por Citomegalovirus , Esofagite , Infecções por HIV/epidemiologia , Neoplasias , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/fisiopatologia , Endoscopia do Sistema Digestório/métodos , Esofagite/diagnóstico , Esofagite/epidemiologia , Esofagite/fisiopatologia , Esofagite/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/terapia , Estudos Retrospectivos , Fatores de Risco , Avaliação de Sintomas/métodos , Taiwan/epidemiologia
3.
Int J Oral Maxillofac Surg ; 44(12): 1480-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26149939

RESUMO

The association between XRCC6/Ku70, an upstream player in the DNA double-strand break repair system, and the risk of nasopharyngeal carcinoma (NPC) was examined. In this case-control study, 176 NPC patients and 352 cancer-free controls were genotyped, and the associations of XRCC6 promoter T-991C (rs5751129), promoter G-57C (rs2267437), promoter G-31A (rs132770), and intron 3 (rs132774) polymorphisms with NPC risk were evaluated. NPC tissue samples were also assessed for their XRCC6 mRNA and protein expression by real-time quantitative reverse transcription PCR and Western blotting, respectively. With regard to the XRCC6 promoter T-991C, the TC and CC genotypes were associated with a significantly increased risk of NPC compared with wild-type TT genotype (adjusted odds ratio 2.02 and 3.42, 95% confidence interval 1.21-3.32 and 1.28-8.94, P=0.0072 and 0.0165, respectively). The mRNA and protein expression levels for NPC tissues revealed significantly lower XRCC6 mRNA and protein expression in the NPC samples with TC/CC genotypes compared to those with the TT genotype (P=0.0210 and 0.0164, respectively). These findings suggest that XRCC6 may play an important role in the carcinogenesis of NPC and could serve as a chemotherapeutic target for personalized medicine and therapy.


Assuntos
Antígenos Nucleares/genética , Proteínas de Ligação a DNA/genética , Neoplasias Nasofaríngeas/genética , Adolescente , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Carcinoma , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Autoantígeno Ku , Masculino , Carcinoma Nasofaríngeo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Inquéritos e Questionários , Taiwan
4.
Aliment Pharmacol Ther ; 38(9): 1054-64, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24024757

RESUMO

BACKGROUND: The burden of gastroesophageal reflux disease (GERD) is increasing in the Asia area and the majority of GERD patients have non-erosive reflux disease (NERD). AIM: To evaluate the efficacy and safety of sodium alginate suspension compared to omeprazole in adult subjects with NERD. METHODS: In this 4-week, double-blind, parallel study, 195 NERD subjects were randomised to one of two treatment groups: sodium alginate suspension 20 mL three times a day and omeprazole 20 mg once daily. The primary efficacy endpoint was the percentage of patients achieving adequate heartburn or regurgitation relief at day 28 assessed by patient diary. The secondary efficacy endpoints included percentage of patients achieving adequate heartburn or regurgitation relief, change from baseline of the Reflux Disease Questionnaire total score at day 14 and 28 from baseline, and patients' overall satisfaction. RESULTS: In this study, 183 subjects were included in the intent-to-treat population, and 172 subjects were included in the per-protocol population. Non-inferiority of sodium alginate to omeprazole was demonstrated in the intent-to-treat population [difference, 2.7% (53.3% vs. 50.5%, P = 0.175), 95% lower confidence interval -11.9%, above the preset margin of -19%]. All of the secondary efficacy endpoints were comparable between two groups. The incidence of adverse event was relatively low and there was no difference between the two groups (5.4% vs. 5.5% for sodium alginate vs. omeprazole). No severe adverse event was noted in this study. CONCLUSION: The study showed that sodium alginate was as effective as omeprazole for symptomatic relief in patients with non-erosive reflux disease (Clinicaltrials.gov NCT01338077).


Assuntos
Alginatos/uso terapêutico , Refluxo Gastroesofágico/tratamento farmacológico , Omeprazol/uso terapêutico , Inibidores da Bomba de Prótons/uso terapêutico , Administração Oral , Adulto , Alginatos/administração & dosagem , Método Duplo-Cego , Feminino , Refluxo Gastroesofágico/patologia , Fármacos Gastrointestinais/administração & dosagem , Fármacos Gastrointestinais/uso terapêutico , Ácido Glucurônico/administração & dosagem , Ácido Glucurônico/uso terapêutico , Azia/tratamento farmacológico , Azia/etiologia , Ácidos Hexurônicos/administração & dosagem , Ácidos Hexurônicos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Omeprazol/administração & dosagem , Satisfação do Paciente , Inibidores da Bomba de Prótons/administração & dosagem , Inquéritos e Questionários , Suspensões , Resultado do Tratamento
6.
J Cardiovasc Surg (Torino) ; 53(4): 507-16, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22071470

RESUMO

AIM: Although implantation of bone marrow mononuclear cells (BMI) was shown to improve outcomes in patients with severe peripheral arterial occlusive disease (PAOD), little experience has been reported in patients with an arterial occlusion level above the knee, ischemic gangrene, and high cardiovascular risk. This study sought to investigate the timing of gangrene tissue debridement and the safety of BMI in these patients. METHODS: Six "no-option" PAOD patients were enrolled with an arterial occlusion level above the knee, ischemic gangrene, and 3 systemic diseases related to a high cardiovascular risk. The ischemic status was evaluated by measuring the ankle-brachial index (ABI), transcutaneous oxygen pressure (TcPO2), and wound healing after BMI. RESULTS: All patients safely underwent the procedures with intravenous general anesthesia by titrating propofol. Major lower extremity amputation, minor debridement amputation, and debridement surgery were performed in 2 (33.3%), 1 (16.7%), and 2 (33.3%) patients, respectively, 3.1 2.8 months after BMI. Compared to the amputation group (N=3), the salvage group (N=3) had a significantly higher baseline ABI (P=0.02) and a shorter distance between the gangrene site and arterial occlusion site (P=0.01). In the 3 patients who underwent debridement, ABI and TcPO2 significantly improved 1 month after BMI, and gangrenous tissues were debrided 3.8 ± 3.6 (range, 1~8) months after BMI with complete healing within 1 month. CONCLUSION: Autologous BMI therapy is safe in patients at high cardiovascular risk with an arterial occlusion level above the knee and ischemic gangrene. Effective predictors of BMI include the baseline ABI and distance to the ischemia. Gangrene tissue should be debrided at least 1 month after BMI.


Assuntos
Arteriopatias Oclusivas/cirurgia , Transplante de Medula Óssea , Doenças Cardiovasculares/etiologia , Desbridamento , Artéria Femoral/cirurgia , Isquemia/cirurgia , Extremidade Inferior/cirurgia , Idoso , Amputação Cirúrgica , Análise de Variância , Angiografia Digital , Índice Tornozelo-Braço , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/diagnóstico , Monitorização Transcutânea dos Gases Sanguíneos , Transplante de Medula Óssea/efeitos adversos , Constrição Patológica , Desbridamento/efeitos adversos , Feminino , Artéria Femoral/diagnóstico por imagem , Gangrena , Humanos , Isquemia/diagnóstico , Isquemia/etiologia , Salvamento de Membro , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Cintilografia , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Taiwan , Fatores de Tempo , Transplante Autólogo , Resultado do Tratamento , Cicatrização
7.
J Laryngol Otol ; 123(10): 1131-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19646293

RESUMO

OBJECTIVES: Vocal cysts with fold atrophy often result in more severe glottal incompetence than vocal cysts along during phonation. Although total excision or marsupialisation are reliable treatments for vocal fold cysts, any post-operative vocal deficit with significant glottal gap will need further treatment. This study aimed to evaluate the efficacy of combined treatment consisting of marsupialisation of the cyst immediately followed by strap muscle transposition laryngoplasty. METHOD: Under direct laryngomicroscopy, microscissors were used to make a disc-shaped incision encircling the equator of the cyst. After marsupialisation of the cyst, a simultaneous medialisation laryngoplasty with strap muscle transposition was performed. RESULTS: Seven patients with vocal cysts and marked vocal fold atrophy were included in the study. After surgery, subjective improvement in voice quality was reported by all patients. Patients' glottal incompetence and vocal performance were markedly improved. CONCLUSION: Marsupialisation is a simple and effective surgical technique for vocal fold cysts. For cases of vocal cysts with marked vocal fold atrophy, marsupialisation followed by medialisation laryngoplasty with strap muscle transposition may be considered.


Assuntos
Cistos/cirurgia , Doenças da Laringe/cirurgia , Músculos Laríngeos/transplante , Laringoscopia/métodos , Laringe/cirurgia , Prega Vocal/cirurgia , Adulto , Atrofia/patologia , Atrofia/cirurgia , Feminino , Humanos , Laringoscopia/normas , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Retalhos Cirúrgicos , Prega Vocal/patologia , Qualidade da Voz , Adulto Jovem
8.
J Neurol ; 255(6): 831-8, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18458862

RESUMO

Glycogen-storage disease type II (GSDII; OMIM #232300), an autosomal recessive disorder caused by a deficiency of the glycogen hydrolysis enzyme acid alpha-glucosidase (acid GAA; acid maltase, EC. 3.2.10.20), results in the accumulation of glycogen in the lysosome. We performed a molecular genetic study on 29 patients with infantile-onset glycogen-storage disease type II (GSDII), 6 with juvenile-onset GSDII and one carrier for GSDII. Seventeen different mutations were identified among them; 8 were novel mutations: c.421C > A (p.L141M), c.872T > C (p.L291P), c.893A > C (p.Y298S), c.1375G > A (p.D459N), c.1437G > C (p.K479N), c.1509_1511del (p.A504del), c.1960T > C (p.S654P), and c.2174G > C (p.R725P). One of the mutations identified, c.2238G > C (p.W746C), which was a sequence change of unknown pathogenic significance causing diminished enzyme activity,was found homozygously in a juvenile-onset patient. We also found a juvenile-onset patient with homozygote c.1935C > A mutation which was frequently found in infantile-onset patients. In addition to mutations, we also identified 14 new polymorphisms in the acid alpha-glucosidase gene. The genotype/phenotype correlations indicated that c.2238G > C (p.W746C) is correlated with juvenile- onset GSDII and that c.872T > C (p.L291P) and c.1411_1414del (p.E471fsX5) are correlated with infantile-onset GSDII. Mutational analysis of GAA is useful in genetic counseling and prenatal diagnosis of the disease.


Assuntos
Predisposição Genética para Doença/genética , Doença de Depósito de Glicogênio Tipo II/enzimologia , Doença de Depósito de Glicogênio Tipo II/genética , Mutação/genética , alfa-Glucosidases/genética , Adulto , Povo Asiático/genética , Análise Mutacional de DNA , Regulação Enzimológica da Expressão Gênica/genética , Marcadores Genéticos/genética , Testes Genéticos , Genótipo , Doença de Depósito de Glicogênio Tipo II/etnologia , Homozigoto , Humanos , Pessoa de Meia-Idade , Fenótipo , Polimorfismo Genético/genética , Taiwan
9.
Scand J Rheumatol ; 36(4): 278-84, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17763205

RESUMO

OBJECTIVES: To investigate the association between tumour necrosis factor-alpha (TNFalpha), TNF receptor superfamily member 1A (TNFRSF1A, also known as TNFRI), TNFRSF1B (TNFRII), and interleukin-1beta (IL-1beta) single nucleotide polymorphisms (SNPs) and the susceptibility to persistent palindromic rheumatism (PR). METHODS: Fifty-six unrelated patients with persistent PR and 100 unrelated healthy controls were genotyped for TNFalpha -308G/A, -238G/A, and +488G/A, TNFRSF1A -609G/T and +36A/G, TNFRSF1B +676T/G and +1663G/A, and IL-1beta -511C/T, -31T/C, and +3954C/T using real-time polymerase chain reaction (RT-PCR). RESULTS: The TNFRSF1A +36G allele [odds ratio (OR) = 3.94, p = 0.003, corrected p (p(c)) = 0.03] and the TNFRSF1A +36AG genotype (OR = 4.81, p = 0.002, p(c) = 0.04) were significantly associated with persistent PR. The frequency of TNFRSF1B +676T/+1663A was increased in PR patients (OR = 2.12, p = 0.01), but failed to reach statistical significance after Bonferroni correction. No correlation was observed between persistent PR and TNFalpha, TNFRSF1A -609G/T, or IL-1beta SNPs. CONCLUSIONS: The results of this study provide evidence of an association between persistent PR and SNPs within the TNFRSF1A gene, and suggest that TNFRI is involved in the aetiopathogenesis of PR.


Assuntos
Polimorfismo de Nucleotídeo Único , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Doenças Reumáticas/genética , Adulto , Idade de Início , Anticorpos Antinucleares/sangue , Mapeamento Cromossômico , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 12 , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Interleucina-1beta/genética , Masculino , Pessoa de Meia-Idade , Peptídeos Cíclicos/sangue , Doenças Reumáticas/sangue , Doenças Reumáticas/classificação , Fator Reumatoide/sangue
10.
Rheumatology (Oxford) ; 44(5): 662-5, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15741196

RESUMO

OBJECTIVE: To estimate in a Chinese population the prevalence of undifferentiated spondyloarthropathy (USpA) among first-degree relatives (FDRs) of ankylosing spondylitis (AS) probands, and to compare the clinical features of familial USpA with those of sporadic USpA. METHODS: The FDRs of two separate cohorts of consecutive AS probands were evaluated for the prevalence of USpA, using the Modified New York criteria and the European Spondylitis Study Group criteria for AS and SpA, respectively. Sporadic USpA and FDRs of non-SpA rheumatic patient probands served as separate controls. RESULTS: Among the 301 FDRs of 102 AS probands, 7.0% were USpA. This was 1000 times higher than the 147 FDRs of 40 non-SpA probands (P = 0.00230). Within the AS families, USpA was less male-dominated than AS (33.3 vs 72.5%) (P = 0.006). The only feature distinguishing familial from sporadic USpA was that the percentages of HLA B27 were 100 and 50%, respectively (P<0.001). CONCLUSION: USpA and AS coexist in the same Chinese families, both being predisposed by HLA B27. In these families, a female gender favours the development of USpA rather than AS. A significant subset of sporadic USpA (HLA B27-negative group) has a different genetic predisposition compared with familial USpA.


Assuntos
Predisposição Genética para Doença , Espondiloartropatias/genética , Adulto , China/epidemiologia , Estudos de Coortes , Feminino , Antígeno HLA-B27/análise , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Espondiloartropatias/etnologia , Espondilite Anquilosante/etnologia , Espondilite Anquilosante/genética
11.
Eye (Lond) ; 19(5): 571-4, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15184943

RESUMO

PURPOSE: Pterygium, a complex disease, is associated with ultraviolet radiation, immunoinflammatory process, genetic factors, and virus infection. Ultraviolet radiation induces secretion of proinflammatory cytokines by the ocular surface epithelium, inflammatory cells in the tear fluid, or both. Among these cytokines, tumour necrosis factor (TNF)alpha and interleukin (IL)-1beta activate pterygium body fibroblasts, resulting in a phenotype capable of expressing various proteinases associated with extracellular matrix remodelling, angiogenesis, and fibroblast proliferation, which are important for pterygium formation and recurrence. The genetic factor was proposed to play a role in pterygium formation, but there were few studies to clarify this proposition. For investigating genetic factors, the association between pterygium and TNF-alpha and IL-1beta polymorphisms is evaluated in this study. METHODS: A total of 128 pterygium patients and 103 volunteers without pterygium were enrolled in this study. Polymerase chain reaction-based analysis was used to resolve the TNF-alpha-308 promoter, IL-1beta-511 promoter, IL-1beta exon 5, and IL-1 receptor antagonist (IL-1 Ra) polymorphisms. RESULTS: There were no significant differences in the frequency of genotypes and alleles of TNF-alpha-308 promoter, IL-1beta-511 promoter, IL-1beta exon 5, and IL-1 Ra polymorphisms between both groups. CONCLUSIONS: The correlation between pterygium and TNF-alpha-308 promoter, IL-1beta-511 promoter, IL-1beta exon 5, and IL-1 Ra polymorphisms does not exist and those polymorphisms are not useful genetic markers for pterygium susceptibility. Further studies on other polymorphisms or haplotypes of TNF-alpha and IL-1beta are necessary.


Assuntos
Interleucina-1/genética , Polimorfismo Genético , Pterígio/genética , Fator de Necrose Tumoral alfa/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos
12.
J Phys Chem B ; 109(46): 21831-5, 2005 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-16853835

RESUMO

Taper- and rodlike Si nanowires (SiNWs) are synthesized successfully on Si and Si(0.8)Ge(0.2) substrates. The growth mechanisms of taper- and rodlike SiNWs are proposed to be oxide-assisted growth (OAG) and vapor-liquid-solid (VLS) growth, respectively. For taperlike SiNWs annealed at 1200 degrees C for 3 h, the emission peaks are found at 772, 478, and 413 nm. On the other hand, for rodlike SiNWs annealed at 1200 degrees C for 4 h, emission peaks are found at 783, 516, and 413 nm. From the field-emission measurements, the taperlike Si nanowires exhibit superior field-emission behavior with a turn-on field of 6.3-7.3 V/mum. The field enhancement, beta, has been estimated to be 700 and 1000 at low and high fields, respectively. The excellent field-emission characteristics are attributed to the perfect crystalline structure and the taperlike geometry of the Si nanowires.

13.
Anal Chem ; 77(1): 259-65, 2005 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-15623304

RESUMO

Carboxylated/oxidized diamond nanoparticles (nominal size 100 nm) exhibit exceptionally high affinity for proteins through both hydrophilic and hydrophobic forces. The affinity is so high that proteins in dilute solution can be easily captured by diamonds, simply separated by centrifugation, and directly analyzed by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS). No preseparation of the adsorbed molecules from diamonds is required for the mass spectrometric analysis. Compared to conventional MALDI-TOF-MS, an enhancement in detection sensitivity by more than 2 orders of magnitude is achieved for dilute solution containing cytochrome c, myoglobin, and albumin because of preconcentration of the probed molecules. The lowest concentration detectable is 100 pM for a 1-mL solution. Aside from the enhanced sensitivity, the overall performance of this technique does not show any sign of deterioration for highly contaminated protein solutions, and furthermore, no significant peak broadening and band shift were observed in the mass spectra. The promise of this new method for clinical proteomics research is demonstrated with an application to human blood serum.


Assuntos
Nanopartículas , Proteínas/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Adsorção , Proteínas Sanguíneas/análise , Diamante , Humanos
16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 65(6 Pt 1): 061601, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12188737

RESUMO

An efficient finite volume method is developed for the phase-field simulation of two-dimensional dendritic growth in a forced flow at various supercoolings. The adaptive nature of the method allows the dendrite in a large domain to evolve secondary structures, even at low supercoolings. In addition to good agreement with previous calculations on the tip shape and speed, the effects of forced flow at various supercoolings are investigated and compared with the Oseen-Ivantsov solution and good agreement is found. The steady dendrite shape in all cases continues to have a self-affine nature and the invariant scaling parameters are in good agreement with the estimation.

17.
Shock ; 15(2): 151-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11220644

RESUMO

This study was designed to investigate the role of NO and effect of iNOS inhibitor on the lung neutrophil deposition and damage after burn. In Experiment 1, specific pathogen-free (SPF) Sprague-Dawley rats underwent 35% total body surface area (TBSA) burn. On the 4th, 8th, 16th, and 24th h after burn, blood was collected for peroxynitrite-mediated dihydrorhodamine 123 (DHR 123) oxidation assay, and lung tissues were harvested for myeloperoxidase (MPO) test and histologic study. Pulmonary microvascular dysfunction was quantitated by measuring the extravasation of Evans blue dye (EBD). In Experiment 2, S-methylisothiourea (SMT) was given (7.5 mg/kg, intraperitoneal immediately post-burn) to suppress iNOS activity. On the 8th h after burn, the effect of SMT on blood DHR 123 oxidation, lung MPO, lung damage, and lung iNOS expression were evaluated. Lung MPO activity increased up to a maximum of 2-fold 8 h after burn. Blood DHR 123 oxidation increased up to a maximum of 2-fold 8 h after burn. Lung permeability increased up to a maximum of 2.5-fold 4 h after burn. SMT significantly decreased lung MPO activity, blood DHR 123 oxidation, and lung permeability by 31%, 41%, and 54%, respectively. SMT markedly decreased the thermal injury-induced perivascular and interstitial inflammatory cell infiltration and iNOS staining in bronchiolar epithelium, endothelial cells, and perivascular and interstitial inflammatory cells. In conclusion, thermal injury induces blood DHR 123 oxidation, lung neutrophil deposition, lung iNOS expression, and lung damage. Peroxynitrite might play an important role in thermal injury-induced lung neutrophil deposition and damage. Specific inhibition of lung iNOS expression and blood DHR 123 oxidation with SMT on thermal injury not only attenuated the lung neutrophil deposition, but also reduced lung damage.


Assuntos
Queimaduras/fisiopatologia , Isotiurônio/análogos & derivados , Lesão Pulmonar , Neutrófilos/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Animais , Queimaduras/complicações , Queimaduras/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Feminino , Isotiurônio/farmacologia , Pulmão/enzimologia , Pulmão/patologia , Masculino , Neutrófilos/efeitos dos fármacos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Permeabilidade , Peroxidase/antagonistas & inibidores , Peroxidase/metabolismo , Ratos , Ratos Sprague-Dawley , Rodaminas/sangue
18.
J Formos Med Assoc ; 99(6): 491-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10925556

RESUMO

BACKGROUND AND PURPOSE: Severe burns induce a disruption in gastrointestinal mucosal integrity and facilitate bacterial translocation (BT). Bombesin (BBS), a tetradecapeptide analogous to mammalian gastrin-releasing peptide, can induce the release of all gut hormones except secretin. This study examined the effects of BBS on mucosal immunity in rats after thermal injury. METHODS: Forty-two Sprague-Dawley rats were divided into one sham control group and six burn groups. Burn groups were subjected to 35% total body surface area burn injury. One to 6 days after the injury, six animals (one from each group) were killed every 24 hours. Biliary secretory immunoglobulin A (SIgA), jejunal mucosal height, intestinal permeability, and BT to the mesenteric lymph nodes (MLNs), liver, and spleen were examined. In a second experiment, three groups of rats (6 in each) received either sham treatment and saline injection, or thermal injury and saline injection, or thermal injury and BBS injection. Twenty-four hours after burns or sham treatment, six animals (1 from each group) were killed. The biliary SIgA, jejunal mucosal height, and BT to the MLNs, liver, and spleen were examined. RESULTS: The biliary SIgA decreased to one-seventh of normal levels 1 day after burn injury, and increased thereafter. The jejunal mucosal height decreased significantly to two-thirds of the normal value 1 day after burn injury. The intestinal mucosal permeability increased significantly to three times the normal level 2 days after the burn injury, and decreased thereafter. BBA significantly reduced the BT incidence and significantly increased the biliary SIgA and jejunal mucosal height 1 day after burn injury. CONCLUSIONS: The results of this study show that, in rats, the intestinal permeability increased, the gut mucosal barrier failed, and the gut immunity deteriorated in the first few days after burn injury. BBS therapy helped to restore the postburn gut mucosal barrier in rats, by increasing biliary SIgA levels and the jejunal mucosal height.


Assuntos
Bombesina/farmacologia , Queimaduras/imunologia , Mucosa Intestinal/efeitos dos fármacos , Animais , Translocação Bacteriana/efeitos dos fármacos , Imunidade nas Mucosas/efeitos dos fármacos , Imunoglobulina A Secretora/análise , Mucosa Intestinal/imunologia , Ratos , Ratos Sprague-Dawley
19.
Shock ; 13(2): 135-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10670843

RESUMO

The expression of inducible nitric oxide synthase (iNOS) is increased in the intestine and results in mucosal damage after endotoxin challenge. Although the oral administration of total parenteral nutrition (TPN) solution promotes bacterial translocation (BT) and increases the intestinal permeability, the role of NO in the nutrition-induced loss of mucosal barrier function remains unclear. The distribution of fluorescein isothiocyanate-dextran (FITC-dextran, 4400) across the lumen of small intestine in rat was examined to investigate the role of NOS activity on the intestinal permeability under oral TPN feeding. Fifty-one rats were randomly divided into 4 groups. Group I (control group) was fed with rat chow, group II received TPN solution orally. Groups III and IV received TPN solution supplemented with NOS inhibitors. On day 9, FITC-dextran was injected into the intestinal lumen. After 30 min, blood samples were taken from portal vein and analyzed for plasma FITC-dextran level by fluorescence spectrophotometry. Samples of small intestine were frozen and sectioned in a cryostat for morphological and NOS histochemical studies. Homogenates of small intestine were used for NOS activity measurement. The plasma level of FITC-dextran showed a significant increase (P < 0.05) in rats fed with oral TPN compared with the control ones. Supplement with NOS inhibitors significantly decreased the intestinal permeability in groups III and IV compared with group II. Similarly, the total NOS activities showed a significant 2-fold increase (P< 0.05) in group II, and NOS inhibitors decreased the elevated NOS activity. These data suggest that oral TPN feeding for 9 days leads to an increase in permeability to dextran and the total NOS activity of small intestine, and both induction of the intestinal permeability and NOS activity were inhibited by treatment with NOS inhibitors. Addition of S-methylisothiourea (SMT), an iNOS selective inhibitor, profoundly inhibited 66% of the induced iNOS activity (P < 0.05) and reduced 74% of the diet-induced increase in intestinal permeability (P < 0.05) in group II. The induced permeability change in rats receiving oral TPN is mainly due to the activity of intestinal mucosal iNOS. The induction of iNOS is an important mediator for intestinal barrier dysfunction. Administration of SMT, which specifically decreases iNOS activity, is useful in the prevention of diet-induced barrier failure.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Óxido Nítrico Sintase/antagonistas & inibidores , Nutrição Parenteral Total/efeitos adversos , Administração Oral , Animais , Atrofia/etiologia , Atrofia/prevenção & controle , Translocação Bacteriana/efeitos dos fármacos , Dextranos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Feminino , Fluoresceína-5-Isotiocianato/análogos & derivados , Íleo/patologia , Absorção Intestinal/efeitos dos fármacos , Absorção Intestinal/fisiologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Isotiurônio/análogos & derivados , Isotiurônio/farmacologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Soluções/administração & dosagem , Soluções/efeitos adversos
20.
J Neurochem ; 73(4): 1769-72, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10501227

RESUMO

A >15-fold increase in vasoactive intestinal polypeptide (VIP) mRNA and VIP peptide levels occurred in primary chromaffin cells following exposure to the neurotrophic neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP)-27 with an EC50 of approximately 2 nM. PACAP induction of VIP expression was blocked by methoxyverapamil or by a combination of nimodipine and omega-conotoxin MVIIC, indicating a requirement for PACAP-initiated calcium entry through voltage-dependent calcium channels for regulation of VIP biosynthesis. Ascomycin, which inhibits calcineurin through formation of an ascomycin/FKBP12/calcineurin ternary complex, abolished the PACAP-evoked increase in VIP expression, whereas rapamycin, which also binds to FKBP12 but does not cause inhibition of calcineurin, did not. Cyclosporin A, which inhibits calcineurin through formation of a cyclosporin A/cyclophilin/calcineurin complex, also abolished PACAP-evoked VIP biosynthesis. These data indicate that PACAP regulates the expression of VIP via a signaling pathway that requires calcium influx and activation of calcineurin.


Assuntos
Medula Suprarrenal/metabolismo , Calcineurina/metabolismo , Cálcio/metabolismo , Células Cromafins/metabolismo , Neuropeptídeos/farmacologia , Neurotransmissores/farmacologia , Transcrição Gênica/fisiologia , Peptídeo Intestinal Vasoativo/genética , Medula Suprarrenal/citologia , Animais , Bovinos , Células Cultivadas , Células Cromafins/citologia , Ativação Enzimática , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , RNA Mensageiro/genética , Transcrição Gênica/efeitos dos fármacos
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