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1.
Ann Surg Oncol ; 26(9): 2864-2873, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31183640

RESUMO

BACKGROUND: The impact of cardiorespiratory comorbidity on operative outcomes after esophagectomy remains controversial. This study investigated the effect of cardiorespiratory comorbidity on postoperative complications for patients treated for esophageal or gastroesophageal junction cancer. PATIENTS AND METHODS: A European multicenter cohort study from five high-volume esophageal cancer centers including patients treated between 2010 and 2017 was conducted. The effect of cardiorespiratory comorbidity and respiratory function upon postoperative outcomes was assessed. RESULTS: In total 1590 patients from five centers were included; 274 (17.2%) had respiratory comorbidity, and 468 (29.4%) had cardiac comorbidity. Respiratory comorbidity was associated with increased risk of overall postoperative complications, anastomotic leak, pulmonary complications, pneumonia, increased Clavien-Dindo score, and critical care and hospital length of stay. After neoadjuvant chemoradiotherapy, respiratory comorbidity was associated with increased risk of anastomotic leak [odds ratio (OR) 1.83, 95% confidence interval (CI) 1.11-3.04], pneumonia (OR 1.65, 95% CI 1.10-2.47), and any pulmonary complication (OR 1.52, 95% CI 1.04-2.22), an effect which was not observed following neoadjuvant chemotherapy or surgery alone. Cardiac comorbidity was associated with increased risk of cardiovascular and pulmonary complications, respiratory failure, and Clavien-Dindo score ≥ IIIa. Among all patients, forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio > 70% was associated with reduced risk of overall postoperative complications, cardiovascular complications, atrial fibrillation, pulmonary complications, and pneumonia. CONCLUSIONS: The results of this study suggest that cardiorespiratory comorbidity and impaired pulmonary function are associated with increased risk of postoperative complications after esophagectomy performed in high-volume European centers. Given the observed interaction with neoadjuvant approach, these data indicate a potentially modifiable index of perioperative risk.


Assuntos
Adenocarcinoma/cirurgia , Doenças Cardiovasculares/epidemiologia , Neoplasias Esofágicas/cirurgia , Esofagectomia/efeitos adversos , Complicações Pós-Operatórias , Transtornos Respiratórios/epidemiologia , Adenocarcinoma/patologia , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/etiologia , Estudos de Coortes , Comorbidade , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Carcinoma de Células Escamosas do Esôfago/cirurgia , Junção Esofagogástrica/patologia , Junção Esofagogástrica/cirurgia , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Prognóstico , Transtornos Respiratórios/diagnóstico , Transtornos Respiratórios/etiologia , Taxa de Sobrevida
3.
Dis Esophagus ; 32(4)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30351390

RESUMO

Esophagectomy is an extensive procedure with severe postoperative effects. It can be assumed that the greater the trauma, the longer the nutritional recovery. This retrospective observational single-center cohort study compared weight development after esophagectomy with open and minimally invasive techniques. Three groups were compared in this study, one representing the first 41 patients who underwent the minimally invasive McKeown esophagectomy (MIMK). The second group included the first 84 consecutive patients operated with the minimally invasive Ivor-Lewis esophagectomy (MIIL). The third group comprised 100 consecutive patients operated with open thoracoabdominal Ivor-Lewis esophagectomy (IL). Virtually all patients submitted to a minimally invasive esophagectomy (MIE) and the majority with an IL had a jejunal catheter inserted during operation for postoperative enteral feeding. All together 225 patients were included in this study. The mean weight loss during the first year was 13.1% (±4.1), 11.2% (±6.1), and 9.6% (±7.5) in the IL, MIIL, and MIMK group, respectively (P = 0.85 and P = 0.95, respectively). The median duration of postoperative enteral nutrition support varied substantially within the groups and was 23.5 days in the IL group (range: 0-2033 days), 54.5 days in those having an MIIL (range: 0-308 days; P ≤ 0.001) and 57.0 days among patients in the MIMK group (range: 0-538 days; P ≤ 0.022). There was no difference in the risk of losing at least 10% of the preoperative weight at 3 or 6 months postoperatively between the groups. However, in patients who suffered severe complications (Clavien-Dindo score ≥ IIIb) after MIIL, there was a nonsignificant trend toward a lower risk of a 10% or greater weight loss, 3 months postoperatively. In conclusion, the greater surgical trauma associated with the traditional open esophagectomy was not followed by more severe weight loss, or other signs of poorer nutritional recovery, when compared to minimal invasive surgical techniques.


Assuntos
Neoplasias Esofágicas/fisiopatologia , Esofagectomia/efeitos adversos , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Complicações Pós-Operatórias/fisiopatologia , Redução de Peso , Adulto , Idoso , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Estudos Retrospectivos , Fatores de Tempo
4.
5.
Dis Esophagus ; 31(10)2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-29897443

RESUMO

Minimally invasive esophagectomy (MIE) has been introduced at many centers worldwide as evidence is accumulating that it reduces the risk of postoperative morbidity and mortality and decreases the length of hospital stay compared to conventional open esophagectomy. The study is a single institution cohort study of 366 consecutive patients treated with curative intent for cancer in the esophagus or gastroesophageal junction, comparing MIE to open surgery. The outcomes studied were peroperative bleeding, operation time, lymph node yield, complications, length of stay and overall survival. The results showed that MIE was associated with reduced peroperative bleeding and operation time. The patients in the MIE group had a statistically significant reduced risk of postoperative complications, 60.2% compared to 78.8% in the open group. In the MIE group 28.4% of the patients had postoperative complications classified according to the Clavien-Dindo classification system as grade IIIb-V compared to 38.2% in the open group, P = 0.046. Median hospital stay was reduced with 10 days comparing MIE to open surgery, P < 0.001. Mean number of resected lymph nodes was 31 in the MIE group and 22 in the open group (P < 0.001), while the R0 resections were 91.5% versus 85% (P = 0.057). Overall long-term survival was higher in the MIE group, a difference that however did not reach statistical significance (adjusted hazard ratio for three-year survival 0.76, 95% CI 0.54-1.08). In conclusion, MIE at a high volume center with a devoted specialist team reduces the risk of peroperative bleeding, operation time, and severe postoperative complications compared to open surgery for esophageal or junctional cancer. The number of resected lymph nodes was increased and the R0 resections were similar between the groups indicating a good oncological quality of the surgery.


Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Junção Esofagogástrica/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/mortalidade , Esofagectomia/mortalidade , Feminino , Humanos , Tempo de Internação , Excisão de Linfonodo/métodos , Linfonodos/cirurgia , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/mortalidade , Duração da Cirurgia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Resultado do Tratamento
7.
Andrologia ; 48(3): 347-54, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26174043

RESUMO

Although Lepidium meyenii (maca), a plant growing in Peru's central Andes, has been traditionally used for enhancing fertility and reproductive performance in domestic animals and human beings, effects of maca on reproductive organs are still unclear. This study examined whether feeding the hydroalcoholic extract powder of maca for 6 weeks affects weight of the reproductive organs, serum concentrations of testosterone and luteinising hormone (LH), number and cytoplasmic area of immunohistochemically stained Leydig cells, and steroidogenesis of cultured Leydig cells in 8-week-old male rats. Feeding the extract powder increased weight of seminal vesicles, serum testosterone level and cytoplasmic area of Leydig cells when compared with controls. Weight of prostate gland, serum LH concentration and number of Leydig cells were not affected by the maca treatment. The testosterone production by Leydig cells significantly increased when cultured with 22R-hydroxycholesterol or pregnenolone and tended to increase when cultured with hCG by feeding the extract powder. The results show that feeding the hydroalcoholic extract powder of maca for 6 weeks increases serum testosterone concentration associated with seminal vesicle stimulation in male rats, and this increase in testosterone level may be related to the enhanced ability of testosterone production by Leydig cells especially in the metabolic process following cholesterol.


Assuntos
Lepidium , Células Intersticiais do Testículo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Testosterona/sangue , Animais , Células Cultivadas , Estradiol/sangue , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Hormônio Luteinizante/sangue , Masculino , Tamanho do Órgão/efeitos dos fármacos , Próstata/efeitos dos fármacos , Ratos , Ratos Wistar , Testosterona/biossíntese
8.
Bone Marrow Transplant ; 44(2): 105-11, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19151794

RESUMO

Some studies have shown that intensive glucose control (IGC) improves outcome in the intensive care unit setting. However, it is the benefit of IGC in hematopoietic SCT (HSCT) that is not well defined. Between June 2006 and May 2007, IGC was maintained prospectively after allogeneic HSCT and clinical outcomes were compared with a cohort matched for conditioning regimen, source of stem cells, age and relation to donor. A stratified Cox regression model was used. There were no significant differences in baseline clinical characteristics. The median age was 43.5 years in both groups. The primary diagnosis was a hematologic malignancy. Patients in the IGC group had a lower glucose level (least-square mean, 116.4 vs 146.8 mg per 100 ml, P<0.001) compared to the standard glucose control group. The incidences of documented infections and bacteremia were significantly lower in the IGC group (14 vs 46%, P=0.004, 9 vs 39%, P=0.002, respectively). IGC tended to reduce the incidence of renal dysfunction (19 vs 37%, P=0.36) and the elevation of C-reactive protein (18 vs 38%, P=0.13). This study suggests that IGC has may have a beneficial effect after HSCT. IGC should be evaluated further in a large prospective, randomized study.


Assuntos
Glicemia/análise , Doença Enxerto-Hospedeiro/terapia , Transplante de Células-Tronco Hematopoéticas , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Transplante Homólogo , Resultado do Tratamento
9.
Oncogene ; 20(46): 6724-30, 2001 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-11709707

RESUMO

To search for anti-cancer agents, a screening system for Ras signal inhibitors was developed using a NIH3T3 cell line with an introduced reporter gene which is controlled by the Ras-responsive element (RRE). With this screening system, malolactomycin D was identified as a selective inhibitor of transcription from the RRE. This compound was found to preferentially inhibit the anchorage-independent growth rather than the anchorage-dependent growth of Ras-transformed NIH3T3 cells. The expression of matrix metalloproteinases MMP-1 and MMP-9, which have RRE in their promoters, were reduced by treatment with malolactomycin D at the translational and transcriptional levels. Analysis of the activity of mitogen-activated protein (MAP) kinases, which play important roles in transduction of the Ras signal, showed that malolactomycin D inhibits the activation of p38 MAP kinase and Jun N-terminal-kinase (JNK) but not extracellular signal-regulated kinase 1 or 2 (ERK1 or 2). These findings suggest that by inhibiting the pathway that leads to the activation of p38 MAP kinase and JNK, malolactomycin D suppresses the expression of MMPs. Since MMPs play important roles in metastasis and maintenance of the microenvironment of tumor cells, both of which facilitate tumor growth, the inhibition of MMPs by malolactomycin D is believed to contribute to its ability to inhibit Ras-mediated tumorigenesis.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Macrolídeos , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Transcrição Gênica , Proteínas ras/metabolismo , Células 3T3 , Ágar/metabolismo , Animais , Northern Blotting , Western Blotting , Divisão Celular , Transformação Celular Neoplásica , Relação Dose-Resposta a Droga , Proteínas Quinases JNK Ativadas por Mitógeno , Luciferases/metabolismo , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Metástase Neoplásica , Regiões Promotoras Genéticas , Fatores de Tempo , Transfecção , Proteínas Quinases p38 Ativadas por Mitógeno
10.
Infect Immun ; 69(11): 6660-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11598035

RESUMO

Adherence of enterohemorrhagic Escherichia coli (EHEC) to the intestinal epithelium is critical for initiation of a bacterial infection. An in vitro infection study previously indicated that EHEC bacteria initially adhere diffusely and then proliferate to develop MC, a process that is mediated by various secreted proteins, such as EspA, EspB, EspD, Tir, and intimin, as well as other putative adherence factors. In the present study, we investigated the role of a large 93-kb plasmid (pO157) in the adherence of O157:H7 (O157Sakai) and found the toxB gene to be involved in the full adherence phenotype. A pO157-cured strain of O157Sakai (O157Cu) developed microcolonies on Caco-2 cells; however, the number of microcolonies was lower than that of O157Sakai, as were the production and secretion levels of EspA, EspB, and Tir. Introduction of a mini-pO157 plasmid (pIC37) composed of the toxB and ori regions restored full adherence capacity to O157Cu, including production and secretion of the proteins. In contrast, introduction of a pO157 mutant possessing toxB::Km into O157Cu could not restore the full adherence phenotype. Expression of truncated versions of His-tagged ToxB also promoted EspB production and/or secretion by O157Cu. These results suggest that ToxB contributes to the adherence of EHEC to epithelial cells through promotion of the production and/or secretion of type III secreted proteins.


Assuntos
Aderência Bacteriana/fisiologia , Escherichia coli O157/genética , Proteínas de Escherichia coli/fisiologia , Genes Bacterianos/fisiologia , Células CACO-2 , Células Epiteliais/microbiologia , Escherichia coli O157/fisiologia , Humanos , Fenótipo , Plasmídeos , Processamento Pós-Transcricional do RNA
11.
Infect Immun ; 69(5): 3164-74, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11292737

RESUMO

The enteric pathogen Salmonella enterica serovar Typhimurium, similar to other facultative intracellular pathogens, has been shown to respond to the hostile conditions inside macrophages of the host organism by producing a set of stress proteins that are also induced by various environmental stresses. The stress-induced ClpXP protease is a member of the ATP-dependent proteases, which are known to be responsible for more than 90% of all proteolysis in Escherichia coli. To investigate the contribution of the ClpXP protease to the virulence of serovar Typhimurium we initially cloned the clpP and clpX operon from the pathogenic strain serovar Typhimurium chi3306 and then created insertional mutations in the clpP and/or clpX gene. The Delta clpP and Delta clpX mutants were used to inoculate BALB/c mice by either the intraperitoneal or the oral route and found to be limited in their ability to colonize organs of the lymphatic system and to cause systemic disease in the host. A variety of experiments were performed to determine the possible reasons for the loss of virulence. An oxygen-dependent killing assay using hydrogen peroxide and paraquat (a superoxide anion generator) and a serum killing assay using murine serum demonstrated that all of the serovar Typhimurium Delta clpP and Delta clpX mutants were as resistant to these killing mechanisms as the wild-type strain. On the other hand, the macrophage survival assay revealed that all these mutants were more sensitive to the intracellular environment than the wild-type strain and were unable to grow or survive within peritoneal macrophages of BALB/c mice. In addition, it was revealed that the serovar Typhimurium ClpXP-depleted mutant was not completely cleared but found to persist at low levels within spleens and livers of mice. Interferon gamma-deficient mice and tumor necrosis factor alpha-deficient mice failed to survive the attenuated serovar Typhimurium infections, suggesting that both endogenous cytokines are essential for regulation of persistent infection with serovar Typhimurium.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Escherichia coli , Interferon gama/fisiologia , Salmonelose Animal/etiologia , Salmonella typhimurium/genética , Serina Endopeptidases/genética , Fator de Necrose Tumoral alfa/fisiologia , Adenosina Trifosfatases/fisiologia , Animais , Mapeamento Cromossômico , Endopeptidase Clp , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Salmonella typhimurium/patogenicidade , Serina Endopeptidases/fisiologia , Virulência
12.
Exp Cell Res ; 265(1): 54-63, 2001 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11281643

RESUMO

We previously found that fibronectin (FN) had a functional site (YTIYVIAL sequence in the 14th type III module) suppressing the integrin-mediated cell adhesion to extracellular matrix. FN-derived peptides containing this antiadhesive site were also shown to regulate cellular processes such as proliferation, differentiation, and apoptosis. The present study shows that the FN-derived antiadhesive peptides suppress the myofibroblastic conversion of rat hepatic stellate cells (HSC). Freshly isolated HSC underwent myofibroblastic conversion during culture in the presence of FBS, as evaluated by indices representing the phenotypic activation of HSC, including increased proliferation, consumption of vitamin A-enriched lipid droplets, and expression of alpha-smooth muscle actin. However, appearance of these myofibroblastic characters was suppressed by coculturing HSC with the FN-derived antiadhesive peptides. On the other hand, the activated HSC, which had already acquired the myofibroblastic phenotype through repeated subculture, secreted FN and then stimulated matrix assembly of ED-A (+) cellular FN as well as plasma FN, while the FN-derived antiadhesive peptides inhibited them. Furthermore, the FN-derived antiadhesive peptides suppressed the integrin-mediated adhesion of the primary HSC to plasma FN and ED-A (+) cellular FN substrates. These results suggested that the FN-derived antiadhesive peptides down-regulated the myofibroblastic conversion of HSC in an indirect manner by inhibiting the integrin-mediated adhesive interaction of HSC with ED-A (+) cellular FN.


Assuntos
Fibronectinas/metabolismo , Hepatócitos/citologia , Sequência de Aminoácidos , Animais , Adesão Celular , Divisão Celular , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibronectinas/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Peptídeos/metabolismo , Peptídeos/farmacologia , Fenótipo , Ratos , Ratos Wistar
14.
J Gastroenterol Hepatol ; 15(4): 374-80, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10824880

RESUMO

BACKGROUND: It has been suggested that gastric mucosal injury induced by Helicobacter pylori infection is mediated by interleukin-8 (IL-8). METHODS: We studied the effect of plaunotol, a drug extracted from the Plau-noi tree of Thailand, and reported it to be effective in the treatment of ulcers, of IL-8 secretion induced by H. pylori and of the inhibitory adhesion activity of the bacterium to gastric epithelial cells. Moreover, the therapeutic effect of plaunotol on H. pylori infection was assessed by using the gnotobiotic murine model. RESULTS: Plaunotol inhibited the growth of H. pylori (1.5 x 10(4) c.f.u./mL) at high doses (24-48 microg/mL), but not at low doses (3-6 microg/mL). Interleukin-8 secretion induced by H. pylori was inhibited by coculture with plaunotol in a dose-dependent manner. The adhesion of H. pylori to MKN45 cells was also suppressed by coculture with plaunotol in a dose-dependent manner. An in vivo study showed that plaunotol improved histological gastritis and decreased the H. pylori antibody titre. CONCLUSIONS: These findings suggest that plaunotol has a therapeutic effect on gastritis induced by H. pylori.


Assuntos
Antiulcerosos/uso terapêutico , Álcoois Graxos/uso terapêutico , Mucosa Gástrica/efeitos dos fármacos , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Interleucina-8/metabolismo , Úlcera Gástrica/tratamento farmacológico , Administração Oral , Animais , Antiulcerosos/administração & dosagem , Anticorpos Antibacterianos/análise , Aderência Bacteriana/efeitos dos fármacos , Diterpenos , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Álcoois Graxos/administração & dosagem , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/fisiologia , Humanos , Imunoensaio , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Coelhos , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Úlcera Gástrica/metabolismo , Úlcera Gástrica/microbiologia , Úlcera Gástrica/patologia , Células Tumorais Cultivadas/efeitos dos fármacos
15.
Infect Immun ; 68(6): 3448-54, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10816497

RESUMO

We previously established a monoclonal antibody (MAb), designated H9, which reacts with the heat shock protein 60 (HSP60) homologue of Helicobacter pylori as well as with other bacterial and human HSP60s. To determine the importance of a cross-reactive epitope on H. pylori HSP60 in H. pylori immunopathogenesis, we performed (i) mapping of an epitope on H. pylori HSP60 recognized by the H9 MAb, (ii) analysis of immunoglobulin G responses of patients with or without H. pylori infection to its epitope region, and (iii) studies of the protective effect of immunization with its epitope region on H. pylori infection in mice. The epitope recognized by the H9 MAb was mapped to the sequence of amino acids 189 to 203 (VEGMQFDRGYLSPYF) on the H. pylori HSP60 molecule. It was confirmed that the synthesized peptide designated pH9 was recognized by the H9 MAb. Enzyme-linked immunosorbent assay analysis showed that patients with H. pylori infection (n = 349) had significantly lower titers of pH9 antibody than did uninfected patients (n = 200) (P < 0.001), but this was not the case with purified H. pylori HSP60 recombinant Escherichia coli GroEL, or recombinant human HSP60. In C57BL/6 mice immunized with the pH9 peptide with Freund's complete adjuvant (FCA), the number of H. pylori organisms colonizing the stomach was significantly lower than that in mice immunized with pCont plus FCA (P < 0.0001) or FCA only (P < 0.005). The results suggest that the immune response to the cross-reactive epitope (pH9 region) on H. pylori HSP60 is unique and might be associated with protection against H. pylori infection.


Assuntos
Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Chaperonina 60/imunologia , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Antígenos de Bactérias/genética , Chaperonina 60/genética , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Epitopos , Escherichia coli/genética , Feminino , Infecções por Helicobacter/sangue , Humanos , Immunoblotting , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Peptídeos/imunologia , Peptídeos/uso terapêutico , Proteínas Recombinantes/imunologia
16.
J Gastroenterol Hepatol ; 15(2): 168-74, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10735541

RESUMO

BACKGROUND: Gastric mucosal injury by Helicobacter pylori has been suggested to be mediated by various cytokines induced by this organism. Nitric oxide (NO) is an important effector molecule involved in immune regulation and defence. To clarify the mechanisms by which H. pylori induces gastric mucosal cell injury, we examined whether H. pylori induces gastric epithelial death via NO production. METHODS: Cytotoxic and non-cytotoxic strains of H. pylori were used. The death of MKN45 cells caused by H. pylori was examined by the 3-(4,5-dimethyl-thiazole-2yl)-2,5-diphenyl tetrazolium bromide (MTT) assays. Aminoguanidine was used to inhibit inducible nitric oxide synthase (iNOS) activity. Expression of iNOS mRNA was determined by the reverse transcriptase-polymerase chain reaction and the DNA fragmentation analysis was performed by using agarose gel electrophoresis. RESULTS: The MTT assay revealed that neither viable H. pylori nor other components of the microorganism induced cell death. Both preincubation of MKN45 cells with interferon-gamma for 6 h and coculture with TNF-alpha significantly increased the cytotoxicity of H. pylori. Both cytotoxic and non-cytotoxic strains of H. pylori induced cell death. Expression of iNOS mRNA was observed in MKN45 cells at 6, 8 and 12 h after H. pylori inoculation. The cytotoxicity of H. pylori was inhibited by aminoguanidine and DNA fragmentation analysis showed that H. pylori induced apoptosis. CONCLUSIONS: These findings suggested that viable H. pylori induces apoptosis of gastric epithelial cells via nitric oxide. Our study indicated that iNOS expression plays an important role in gastric cell injury.


Assuntos
Apoptose , Mucosa Gástrica/microbiologia , Helicobacter pylori , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico/biossíntese , Linhagem Celular , Células Epiteliais , Mucosa Gástrica/citologia , Humanos , Técnicas In Vitro , Óxido Nítrico Sintase Tipo II , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Vet Pathol ; 37(1): 104-7, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10643991

RESUMO

Histopathologic and immunohistochemical examinations were performed on localized amyloidosis associated with mammary tumors in two dogs. These tumors were identified as adenoma and adenocarcinoma. An acellular, amorphous pale eosinophilic material (amyloid) was observed in the lumina of acini lined by neoplastic cells and in the stroma of the tumors. Concentrically laminated pale eosinophilic bodies (corpora amylacea) were also found in the lumina of the acini. Amyloid and corpora amylacea stained positively with Congo red with and without 5% potassium permanganate pretreatment and revealed a green birefringence under polarized light. Corpora amylacea showed an occasional Maltese-cross pattern. Immunohistochemically, amyloid and corpora amylacea usually stained positively with anti-bovine alpha-casein antibody but negatively with anti-human amyloid AA, anti-bovine kappa-light and lambda-light chains, anti-human lactoferrin, anti-human transferrin, anti-human secretory component, and anti-human polyglucosan antibodies. These findings suggested that the amyloid deposition in these canine mammary tumors was related to lactating casein.


Assuntos
Adenocarcinoma Papilar/veterinária , Adenoma/veterinária , Amiloidose/veterinária , Doenças do Cão/patologia , Neoplasias Mamárias Animais/patologia , Adenocarcinoma Papilar/patologia , Adenocarcinoma Papilar/cirurgia , Adenoma/patologia , Adenoma/cirurgia , Amiloide/análise , Amiloidose/patologia , Animais , Doenças do Cão/cirurgia , Cães , Evolução Fatal , Feminino , Imuno-Histoquímica , Neoplasias Mamárias Animais/cirurgia , Microscopia de Polarização/veterinária , Metástase Neoplásica
19.
Cell Stress Chaperones ; 4(2): 118-28, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10547061

RESUMO

Listeria monocytogenes is a facultative intracellular pathogen which can escape bactericidal mechanisms and grow within macrophages. The intracellular environment of macrophages is one of the most stressful environments encountered by an invading bacterium during the course of infection. To study the role of the major stress protein, DnaK, of L. monocytogenes in survival under intracellular stress induced by macrophage-phagocytosis as well as under extracellular environmental stresses, we cloned, sequenced, and analyzed the dnaK locus from L. monocytogenes. Then we constructed an insertional mutation in the dnaK gene by homologous recombination and characterized it. Sequencing has revealed that the dnaK locus consists of four open reading frames in the order hrcA-grpE-dnaK-dnaJ. The mutant grows neither at temperatures above 39 degrees C nor under acidic conditions e.g. pH 3.0. Using the macrophage cell line JA-4, the ability of the dnaK mutant to grow intracellularly was examined. Immediately after phagocytosis, the number of viable dnaK mutant bacteria found within macrophages was significantly lower compared to that of intracellular wild type bacteria. However, following a 1-3 h latency period, the mutant multiplied in a similar fashion to the wild type within macrophage cells. A quantitative analysis of intracellular bacteria in macrophage cells by microscope and a binding assay of bacteria to the surface of macrophages by ELISA revealed that the lower number of viable dnaK mutant in macrophages after phagocytosis is due to the low efficiency of phagocytosis resulting from the reduced binding capacity of the dnaK mutant. These results demonstrate that DnaK of L. monocytogenes is essentially required for survival under high temperatures and acidic conditions. Though it does not largely contribute to the survival of L. monocytogenes in macrophage cells, it is essential for efficient phagocytosis. This is the first evidence that DnaK is required for the efficient phagocytosis of a facultative intracellular pathogen with macrophages.


Assuntos
Proteínas de Escherichia coli , Proteínas de Choque Térmico HSP70/fisiologia , Listeria monocytogenes/metabolismo , Macrófagos/imunologia , Fagocitose , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática , Escherichia coli , Proteínas de Choque Térmico HSP70/genética , Camundongos , Microscopia Eletrônica , Dados de Sequência Molecular , Mutagênese Insercional , Propriedades de Superfície , Temperatura
20.
Hepatogastroenterology ; 46(29): 2961-4, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10576382

RESUMO

A resected case of metastatic liver carcinoid is presented. A 62 year-old woman, who had undergone removal of a typical bronchial carcinoid 19 years before, was found to have a well-defined, oval hepatic tumor on ultrasonography. The resected specimen was a hard and solid tumor, which was microscopically diagnosed as a carcinoid. Histological review of the previously resected lung tumor revealed that the liver tumor was a metastasis from the primary bronchial carcinoid. The patient is alive without recurrence 42 months after hepatectomy. This case suggests that typical bronchial carcinoid, a slowly growing tumor, may metastasize to distant sites after many years, and that re-excision of metastatic lesions may prolong survival time.


Assuntos
Tumor Carcinoide/secundário , Hepatectomia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/cirurgia , Tumor Carcinoide/patologia , Tumor Carcinoide/cirurgia , Feminino , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Pneumonectomia , Reoperação
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