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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
2.
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
3.
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
4.
Lett Appl Microbiol ; 64(4): 254-260, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28140472

RESUMO

Previously, we reported a positive effect the probiotic formulation, Lactobacillus acidophilus INMIA 9602 Er-2 strain 317/402 (Narine strain), had on the blood characteristics of patients with familial Mediterranean fever disease (FMF). The aim of this investigation was to evaluate the effect of the Narine probiotic on growth characteristics in the predominant commensal Escherichia coli isolates from the gut microbiota in FMF-positive study participants. Bacterial growth of 192 prevalent commensal E. coli isolates found in the volunteer participants' guts was evaluated using Verhulst's logistic function. This study showed that the duration of the preparatory growth phase for the E. coli isolates collected from FMF-positive volunteers was significantly shorter, whereas the duration of the logarithmic growth phase was significantly longer (P < 0·03) than that of the isolates collected from healthy participants. The Narine probiotic formulation caused a significant extension (P < 0·001) of the preparatory growth phase in the commensal E. coli isolated from FMF subjects a month after the Narine probiotic administration was terminated. The data suggest that the mathematical model characterizes the growth of commensal E. coli isolates from FMF-positive participants and it can be useful in a decision-making process on the practical use of probiotics during FMF. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to demonstrate the effects of Narine, containing the probiotic Lactobacillus acidophilus, on the growth of gut commensal Escherichia coli from study participants with familial Mediterranean fever disease (FMF). Verhulst's logistic function was demonstrated to act as a possible tool for the evaluation and quantification of effects produced by the probiotic formulation in FMF participants.


Assuntos
Escherichia coli/crescimento & desenvolvimento , Febre Familiar do Mediterrâneo/microbiologia , Microbioma Gastrointestinal , Lactobacillus acidophilus/fisiologia , Probióticos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Adulto Jovem
5.
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
6.
9.
Lett Appl Microbiol ; 48(4): 465-71, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19187492

RESUMO

AIMS: We examined whether the presence of Helicobacter is related to that of Acanthamoeba in river and soil environments. METHODS AND RESULTS: The samples (river n = 51, soil n = 75) were collected in Sapporo City, Japan. PCR with primers for Helicobacter genus-specific and standard culture techniques were used to detect helicobacter. Prevalence of acanthamoeba was also evaluated by genus-specific PCR. The prevalence of Helicobacter genus-specific DNA in river water samples and in soil samples was 88% and 0%, respectively. No successful culture of helicobacter was achieved. The prevalence of Acanthamoeba genus-specific DNA in river samples and in soil samples was 61% and 96%, respectively. No statistical correlation between the prevalence of helicobacter and either that of acanthamoeba or water quality parameters (pH, turbidity and coliform group) except for temperature was found. CONCLUSIONS: We revealed the presence of helicobacter in river water and non-existence of helicobacter in soil. However, the distribution of helicobacter did not overlap with that of acanthamoeba in rivers. SIGNIFICANCE FOR IMPACT OF THE STUDY: The role of acanthamoeba on the survival of helicobacter might be limited as the both are coincidentally present in the environment.


Assuntos
Acanthamoeba/isolamento & purificação , Helicobacter pylori/isolamento & purificação , Rios , Microbiologia do Solo , Solo/parasitologia , Acanthamoeba/genética , Animais , Primers do DNA , DNA Bacteriano/análise , DNA Bacteriano/isolamento & purificação , DNA de Protozoário/análise , DNA de Protozoário/isolamento & purificação , Helicobacter pylori/genética , Humanos , Japão , Reação em Cadeia da Polimerase/métodos , Prevalência , Rios/química , Rios/microbiologia , Rios/parasitologia , Sensibilidade e Especificidade
10.
Int J Tuberc Lung Dis ; 10(11): 1286-91, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17131790

RESUMO

OBJECTIVE: To determine the significance of Pneumocystis jirovecii infection in the Kenyan paediatric population. DESIGN: Sixty samples of induced sputum from children aged < or =23 months, half of whom were human immunodeficiency virus (HIV) positive, admitted with severe pneumonia in Nairobi were subjected to immunofluorescent staining for detection of P. jirovecii and microbiological culture. RESULTS: P. jirovecii was detected in 8/60 (13%) as a copathogen with other respiratory pathogens. Five of eight samples with >5 oocysts were from HIV-positive children aged < or =6 months, while equivocally scored samples (< or =5 oocysts) were from HIV-negative children aged >6 months. Klebsiella pneumoniae was significantly recovered in 26/ 60 (43%), followed by Escherichia coli 11/60 (18%) and Staphylococcus aureus 8/60 (13%). Streptococcus pneumoniae, Haemophilus influenzae and Pseudomonas aeruginosa were isolated infrequently. Candida albicans was recovered from 27/60 (45%), while the frequency of C. tropicalis, C. glabrata and C. parapsilosis was 7%, 5% and 3% respectively. Multidrug resistance among E. coli and K. pneumoniae were: sulphamethoxazoletrimethoprim 100% vs. 69%, chloramphenicol 55% vs. 73% and ampicillin 100% vs. 89%. CONCLUSION: Paediatricians in Kenya should be aware of Pneumocystis pneumonia, irrespective of the patient's HIV status.


Assuntos
Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/microbiologia , População Urbana , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Pré-Escolar , Humanos , Incidência , Lactente , Quênia/epidemiologia , Pneumonia por Pneumocystis/epidemiologia , Estudos Retrospectivos , Índice de Gravidade de Doença
11.
Hum Exp Toxicol ; 35(8): 818-32, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26437792

RESUMO

Probiotics are live microorganisms ingested for the purpose of conferring a health benefit on the host. Development of new probiotics includes the need for safety evaluations that should consider factors such as pathogenicity, infectivity, virulence factors, toxicity, and metabolic activity. Clostridium butyricum MIYAIRI 588(®) (CBM 588(®)), an anaerobic spore-forming bacterium, has been developed as a probiotic for use by humans and food animals. Safety studies of this probiotic strain have been conducted and include assessment of antimicrobial sensitivity, documentation of the lack of Clostridium toxin genes, and evaluation of CBM 588(®) on reproductive and developmental toxicity in a rodent model. With the exception of aminoglycosides, to which anaerobes are intrinsically resistant, CBM 588(®) showed sensitivity to all antibiotic classes important in human and animal therapeutics. In addition, analysis of the CBM 588(®) genome established the absence of genes for encoding for α, ß, or ε toxins and botulin neurotoxins types A, B, E, or F. There were no deleterious reproductive and developmental effects observed in mice associated with the administration of CBM 588(®) These data provide further support for the safety of CBM 588(®) for use as a probiotic in animals and humans.


Assuntos
Anormalidades Induzidas por Medicamentos , Antibacterianos/farmacologia , Toxinas Bacterianas/genética , Clostridium butyricum/genética , Probióticos/toxicidade , Reprodução/efeitos dos fármacos , Anormalidades Induzidas por Medicamentos/etiologia , Animais , Toxinas Botulínicas/genética , Clostridium butyricum/efeitos dos fármacos , Farmacorresistência Bacteriana , Enterotoxinas/genética , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Neurotoxinas/genética , Gravidez , Probióticos/farmacologia , Probióticos/normas
12.
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
13.
Neuroscience ; 82(4): 999-1007, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9466424

RESUMO

Phosphoinositide-specific phospholipase C is a key enzyme in signal transduction. We have previously demonstrated that an isozyme of phospholipase C, phospholipase C-delta1, accumulates aberrantly in the brains of patients with Alzheimer's disease. In the present study, we examined the property of phospholipase C isozymes in human brains using the methods of chromatofocusing and gel filtration chromatography, and investigated their changes in Alzheimer's disease brains. The chromatofocusing profile of human brain phospholipase C activity on a Mono P HR column demonstrated that phospholipase C-gamma1, exhibiting an isoelectric point value of 5.2, and phospholipase C-delta1, exhibiting isoelectric point values of 5.2 and 4.6, are partly overlapped in their elution. In contrast, the elution profiles of control and Alzheimer's disease brain phospholipase C on Superdex 200 pg column gel filtration chromatography indicated that phospholipase C-gamma1 and phospholipase C-delta1 can be separated with the elution position having a molecular weight of about 240,000 and 140,000, respectively, in the human brain. Using this gel filtration chromatography it was revealed that the phospholipase C-gamma1 activity was significantly decreased and the phospholipase C-delta1 activity was significantly increased in Alzheimer's disease brains compared with controls. These results suggest that the phospholipase C isozymes are differentially involved in Alzheimer's disease.


Assuntos
Doença de Alzheimer/enzimologia , Encéfalo/enzimologia , Isoenzimas/química , Fosfolipases Tipo C/química , Idoso , Doença de Alzheimer/patologia , Encéfalo/patologia , Cromatografia , Cromatografia em Gel , Humanos , Imunoquímica , Peso Molecular
14.
Cell Stress Chaperones ; 5(1): 21-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10701836

RESUMO

The complete dnaK operon of Listeria monocytogenes was isolated by chromosome walking using the previously cloned dnaK gene as a probe. Molecular analysis of the locus identified 6 genes in the order hrcA, grpE, dnaK, dnaJ, orf35, and orf29. Primer extension analysis revealed 3 transcription start sites-S1, S2, and S3-upstream of the hrcA, grpE, and dnaJ, respectively. The transcription from S1 was heat inducible. Analysis of the sequences revealed the consensus promoter sequences of gram-positive bacteria, P1 and P2 upstream of the hrcA and dnaJ, respectively. The hrcA gene and a regulatory sequence, designated CIRCE (controlling inverted repeat of chaperone expression), play a role in the regulation of expression of the dnaK locus in response to heat shock in several gram-positive bacteria. Their presence upstream of the dnaK locus in L. monocytogenes suggested a similar regulatory mechanism for the transcription initiated at the promoter, P1. Northern blot analysis led to the detection of 4 mRNA species of 4.9 kb, 3.6 kb, 3.6 kb, and 1.2 kb; the first 2 species were heat inducible. The current results indicate that 4 distinct transcripts directed by 3 promoters are involved in the expression of the dnaK operon of L. monocytogenes.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Escherichia coli , Genes Bacterianos , Proteínas de Choque Térmico HSP70/genética , Listeria monocytogenes/genética , Óperon , Regiões Promotoras Genéticas , Sequência de Aminoácidos , Bactérias/genética , Clonagem Molecular , Proteínas de Ligação a DNA , Regulação Bacteriana da Expressão Gênica , Proteínas de Choque Térmico HSP40 , Proteínas de Choque Térmico/genética , Temperatura Alta , Dados de Sequência Molecular , Peso Molecular , RNA Mensageiro/genética , Sequências Reguladoras de Ácido Nucleico , Proteínas Repressoras/genética , Análise de Sequência , Especificidade da Espécie , Transcrição Gênica
15.
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
16.
J Biochem ; 98(1): 149-56, 1985 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2931425

RESUMO

Heavy meromyosin (HMM) and subfragment-1 (S1) were obtained from squid mantle myosin by tryptic digestion and chymotryptic digestion, respectively. Squid HMM(T) and S1(CT) preparations contained stoichiometric amounts of the two types of light chain subunit; regulatory light chain, LC-2, and essential light chain, LC-1. No difference was detected in the chymotryptic digestibilities of squid mantle myosin in Ca-medium and in EDTA-medium. This is in contrast to the digestibility of scallop adductor myosin. The Mg-ATPase activity of HMM(T) alone and that of acto-HMM(T) were both sensitive to calcium ions. In contrast, the activity of S1(CT) alone and that of acto-S1(CT) were both insensitive to calcium ions. The affinity of HMM(T) for actin was not affected by calcium ions, but the amount of HMM(T) bound to actin was increased by calcium ions from 20% to 60% of the total amount of HMM(T). On the other hand, the actin affinity of S1(CT) and the amount of S1(CT) bound to actin were both unaffected by calcium ions. The role of calcium ions in the regulation of contraction in molluscan muscles is discussed.


Assuntos
Adenosina Trifosfatases/metabolismo , Decapodiformes/análise , Subfragmentos de Miosina/isolamento & purificação , Miosinas/isolamento & purificação , Fragmentos de Peptídeos/isolamento & purificação , Actinas/metabolismo , Actomiosina/metabolismo , Animais , ATPase de Ca(2+) e Mg(2+)/metabolismo , Cálcio/metabolismo , Quimotripsina/metabolismo , Ativação Enzimática , Substâncias Macromoleculares , Peso Molecular , Subfragmentos de Miosina/metabolismo , Miosinas/metabolismo , Fragmentos de Peptídeos/metabolismo , Cloreto de Potássio/farmacologia , Ligação Proteica , Tripsina/metabolismo , Ureia/farmacologia
17.
Histol Histopathol ; 6(1): 21-4, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1806052

RESUMO

The brain from a Siamese cat with sphingomyelinosis was examined with lectin histochemistry. Swollen neurons were stained with Canavalia ensiformis agglutinin (Con A). Some of them were also stained with Ricinus communis agglutinin-I (RCA-I) and Ulex europaeus agglutinin-I (UEA-I). A small number of axonal spheroids and glia cells were positive for Con A, RCA-I, UEA-I and wheat germ agglutinin. Control tissues were weakly stained with Con A, but not with any of the other lectins. These results indicate that affected neurons contain mannose and glucose residues in addition to sphingomyelin. This study points to the possibility that the characteristics of lectin histochemical study might be helpful for the diagnosis of sphingomyelinosis.


Assuntos
Encéfalo/patologia , Lectinas , Doenças de Niemann-Pick/patologia , Lectinas de Plantas , Esfingomielinas/análise , Animais , Sequência de Carboidratos , Gatos , Concanavalina A , Feminino , Glucose/análise , Manose/análise , Dados de Sequência Molecular , Ricina
18.
FEMS Microbiol Lett ; 168(2): 277-82, 1998 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9835039

RESUMO

We have succeeded in producing monoclonal antibodies which neutralize the vacuolation of rabbit kidney cells by a cytotoxin produced by Helicobacter pylori. Vacuolating activity of several H. pylori strains correlated with ELISA values using these monoclonal antibodies and culture supernatants of the strains. These results indicate that the molecules recognized by the monoclonal antibodies might be the vacuolating toxin produced by H. pylori. In addition, the sera from patients with gastritis and gastric cancer reacted strongly with the antigens captured by the monoclonal antibodies from the supernatant containing H. pylori vacuolating toxin.


Assuntos
Anticorpos Monoclonais/imunologia , Proteínas de Bactérias/imunologia , Citotoxinas/imunologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/imunologia , Helicobacter pylori/metabolismo , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Toxinas Bacterianas/imunologia , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Infecções por Helicobacter/imunologia , Helicobacter pylori/crescimento & desenvolvimento , Helicobacter pylori/isolamento & purificação , Humanos , Immunoblotting , Rim/citologia , Camundongos , Testes de Neutralização , Úlcera Péptica/microbiologia , Coelhos , Neoplasias Gástricas/microbiologia , Vacúolos
19.
FEMS Microbiol Lett ; 65(3): 311-5, 1991 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-1916231

RESUMO

Nine monoclonal antibodies (mAb) to Clostridium difficile toxin A were produced. The isotype of one mAb (37B5) was IgG2b, kappa, and that of the other eight mAbs was IgM, kappa. Immunoblot analysis after non-denatured PAGE showed that with the exception of one mAb (112G6) all mAbs gave a positive reaction with the 540 kDa band of toxin A. Immunoblot analysis showed that four mAbs (2E15, 3B4, 37B5 and 49C4) gave a positive reaction with the 240 kDa major band of toxin A. In neutralisation tests with these mAbs for enterotoxicity, mouse lethality, haemagglutination activity and cytotoxicity, 37B5 neutralised enterotoxicity in a rabbit ileal loop response test but did not neutralise any other biological activities. None of the other eight mAbs showed any neutralising activities at all.


Assuntos
Anticorpos Monoclonais/imunologia , Toxinas Bacterianas , Clostridioides difficile/imunologia , Enterotoxinas/imunologia , Hemaglutinação/imunologia , Íleo/imunologia , Animais , Anticorpos Monoclonais/biossíntese , Western Blotting , Reações Cruzadas , Eletroforese em Gel de Poliacrilamida , Enterotoxinas/antagonistas & inibidores , Enterotoxinas/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Coelhos
20.
FEMS Microbiol Lett ; 175(1): 107-11, 1999 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10361715

RESUMO

To evaluate the viability of Helicobacter pylori cultured under anaerobic conditions, H. pylori strain TK1029 was grown on blood agar in a microaerophilic environment at 37 degrees C for 4 days, and subsequently cultured under anaerobic conditions for 1 to 35 days. Colony formation by bacteria on blood agar plates cultured under anaerobic conditions was observed only for up to 4 days of microaerophilic incubation. By Gram staining, the morphological form of the bacteria was shown to be predominantly coccoid. However, bacteria cultured under anaerobic conditions for 15 to 35 days formed colonies on blood agar after pre-incubation of bacteria with PBS, but not without pre-incubation. These results suggest that H. pylori survives long-term culture under anaerobic conditions and that both pre-incubation in non-nutrient solution and high density of bacterial concentration might be important for recovery of H. pylori cultured for a prolonged time under anaerobic conditions.


Assuntos
Helicobacter pylori/crescimento & desenvolvimento , Anaerobiose , Técnicas Bacteriológicas , Biópsia , Contagem de Colônia Microbiana , Meios de Cultura , Infecções por Helicobacter/microbiologia , Helicobacter pylori/fisiologia , Humanos , Estômago/microbiologia
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