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1.
Colloids Surf B Biointerfaces ; 131: 29-38, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25942700

RESUMO

Thorough understanding of magnetic nanoparticle (MNP) properties is essential for developing new theranostics. In this study, we provide evidence that non-modified magnetic iron oxide nanoparticles and their functionalized derivatives may be used to restrict growth and capture different pathogens. Coprecipitation of Fe(2+) and Fe(3+) ions in an alkaline solution was used to synthesize MNPs that subsequently were functionalized by gold and aminosilane coating. Transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were used to assess their physicochemical properties. A significant decrease of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans outgrown from medium after addition of MNPs or their derivatives was observed during 24h culture. Measurement of optical density revealed that using MNPs, these pathogens can be quickly captured and removed (with efficiency reaching almost 100%) from purposely infected saline buffer and body fluids such as human blood plasma, serum, abdominal fluids and cerebrospinal fluids. These effects depend on nanoparticle concentration, surface chemistry, the type of pathogen, as well as the surrounding environment.


Assuntos
Candida albicans/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Nanopartículas de Magnetita/toxicidade , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Varredura Diferencial de Calorimetria , Candida albicans/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Ouro/química , Ferro/química , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Microscopia Eletrônica de Transmissão , Pseudomonas aeruginosa/crescimento & desenvolvimento , Silanos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/crescimento & desenvolvimento , Fatores de Tempo
2.
J Nanobiotechnology ; 13: 32, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25929281

RESUMO

BACKGROUND: Ceragenins, synthetic mimics of endogenous antibacterial peptides, are promising candidate antimicrobial agents. However, in some settings their strong bactericidal activity is associated with toxicity towards host cells. To modulate ceragenin CSA-13 antibacterial activity and biocompatibility, CSA-13-coated magnetic nanoparticles (MNP-CSA-13) were synthesized. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to characterize MNP-CSA-13 physicochemical properties. Bactericidal action and ability of these new compounds to prevent Pseudomonas. aeruginosa biofilm formation were assessed using a bacteria killing assay and crystal violet staining, respectively. Release of hemoglobin from human red blood cells was measured to evaluate MNP-CSA-13 hemolytic activity. In addition, we used surface activity measurements to monitor CSA-13 release from the MNP shell. Zeta potentials of P. aeruginosa cells and MNP-CSA-13 were determined to assess the interactions between the bacteria and nanoparticles. Morphology of P. aeruginosa subjected to MNP-CSA-13 treatment was evaluated using atomic force microscopy (AFM) to determine structural changes indicative of bactericidal activity. RESULTS: Our studies revealed that the MNP-CSA-13 nanosystem is stable and may be used as a pH control system to release CSA-13. MNP-CSA-13 exhibits strong antibacterial activity, and the ability to prevent bacteria biofilm formation in different body fluids. Additionally, a significant decrease in CSA-13 hemolytic activity was observed when the molecule was immobilized on the nanoparticle surface. CONCLUSION: Our results demonstrate that CSA-13 retains bactericidal activity when immobilized on a MNP while biocompatibility increases when CSA-13 is covalently attached to the nanoparticle.


Assuntos
Antibacterianos/farmacologia , Nanopartículas de Magnetita , Esteroides/química , Antibacterianos/efeitos adversos , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Varredura Diferencial de Calorimetria , Eritrócitos/efeitos dos fármacos , Humanos , Nanopartículas de Magnetita/química , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Pseudomonas aeruginosa/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Esteroides/farmacologia , Termogravimetria
3.
Am J Med Sci ; 349(5): 385-91, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25789686

RESUMO

BACKGROUND: It has been previously demonstrated that patients with reflux esophagitis exhibit a significant impairment in the secretion of salivary protective components versus controls. However, the secretion of salivary protective factors in patients with nonerosive reflux disease (NERD) is not explored. The authors therefore studied the secretion of salivary volume, pH, bicarbonate, nonbicarbonate glycoconjugate, protein, epidermal growth factor (EGF), transforming growth factor alpha (TGF-α) and prostaglandin E2 in patients with NERD and compared with the corresponding values in controls (CTRL). METHODS: Salivary secretion was collected during basal condition, mastication and intraesophageal mechanical (tubing, balloon) and chemical (initial saline, acid, acid/pepsin, final saline) stimulations, respectively, mimicking the natural gastroesophageal reflux. RESULTS: Salivary volume, protein and TGF-α outputs in patients with NERD were significantly higher than CTRL during intraesophageal mechanical (P < 0.05) and chemical stimulations (P < 0.05). Salivary bicarbonate was significantly higher in NERD than CTRL group during intraesophageal stimulation with both acid/pepsin (P < 0.05) and saline (P < 0.01). Salivary glycoconjugate secretion was significantly higher in the NERD group than the CTRL group during chewing (P < 0.05), mechanical (P < 0.05) and chemical stimulation (P < 0.01). Salivary EGF secretion was higher in patients with NERD during mechanical stimulation (P < 0.05). CONCLUSIONS: Patients with NERD demonstrated a significantly stronger salivary secretory response in terms of volume, bicarbonate, glycoconjugate, protein, EGF and TGF-α than asymptomatic controls. This enhanced salivary esophagoprotection is potentially mediating resistance to the development of endoscopic mucosal changes by gastroesophageal reflux.


Assuntos
Refluxo Gastroesofágico , Saliva , Glândulas Salivares , Adulto , Dinoprostona/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Feminino , Refluxo Gastroesofágico/metabolismo , Refluxo Gastroesofágico/fisiopatologia , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Estimulação Física , Saliva/metabolismo , Eliminação Salivar , Glândulas Salivares/metabolismo , Glândulas Salivares/fisiopatologia , Cloreto de Sódio/metabolismo , Estimulação Química , Fator de Crescimento Transformador alfa/metabolismo
4.
Adv Med Sci ; 59(2): 281-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25181642

RESUMO

PURPOSE: A significantly compromised epidermal growth factor (EGF) secretion by basal parotid saliva may contribute to the development of Barrett's esophagus (BE). The rate of secretion of EGF as well as a wide spectrum of protective factors in total basal and stimulated saliva in BE patients remains to be explored. We therefore studied the rate of secretion of salivary buffers, glycoconjugate, protein, EGF, transforming growth factor α (TGFα) and prostaglandin E2 (PGE2), evoked by esophago-salivary reflex, in patients with BE and controls (CTRL). MATERIAL/METHODS: Salivary secretion was collected during basal condition, mastication, and intraesophageal mechanical and chemical stimulations respectively, mimicking the natural gastroesophageal reflux scenario. RESULTS: Salivary pH in BE was significantly lower than in controls during mechanical (p<0.001) and chemical stimulations (p<0.001). Bicarbonate and protein outputs in BE were significantly lower during mechanical (p<0.05) and chemical stimulations (p<0.01). The non-bicarbonate and glycoconjugate outputs in BE were lower during chemical stimulation (p<0.05) and during mechanical (p<0.05) and chemical stimulations (p<0.05) respectively. The rate of salivary EGF output in BE was significantly lower during mechanical stimulation (p<0.05). We observed a higher TGFα output during mastication (p<0.05) and PGE2 secretion during basal and masticatory condition (p<0.05) in BE. CONCLUSIONS: Patients with BE demonstrated significantly compromised salivary pH and rate of secretion of bicarbonate, non-bicarbonate, glycoconjugate, protein and EGF. This impairment could potentially predispose to the development of accelerated esophageal mucosal injury. Potential restoration of this impairment by masticatory stimulation of salivary secretion using sugarless chewing gum justifies further clinical exploration.


Assuntos
Esôfago de Barrett/fisiopatologia , Regulação para Baixo , Esôfago/fisiopatologia , Reflexo Anormal , Glândulas Salivares/fisiopatologia , Salivação , Adulto , Idoso , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade , Saliva/química , Saliva/metabolismo , Glândulas Salivares/metabolismo
5.
Clin Exp Med ; 11(2): 81-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20953890

RESUMO

It is suggested that gastric mucins, and in particular some specific glycan structures that can act as carbohydrate receptors, are involved in the interactions with Helicobacter pylori adhesins. The main aim of our study was to evaluate glycosylation pattern of glycoproteins of gastric juice before and at the end of eradication therapy. Gastric juices were taken from 13 clinical patients and subjected to analysis. Pooled fractions of the void volume obtained after gel filtration were subjected to ELISA tests. To assess the relative amounts of carbohydrate structures, lectins and monoclonal antibodies were used. Changes in the level of MUC 1 and MUC 5AC mucins and of carbohydrate structures, which are suggested to be receptors for Helicobacter pylori adhesins, were observed by the end of the eradication treatment. Our results support the idea about the involvement of MUC 5AC and MUC 1 with some specific sugar structures in the mechanism of Helicobacter pylori infection.


Assuntos
Carboidratos/análise , Suco Gástrico/química , Mucina-5AC/análise , Mucina-1/análise , Adulto , Cromatografia em Gel , Ensaio de Imunoadsorção Enzimática , Feminino , Glicosilação , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade
6.
Am J Physiol Cell Physiol ; 300(1): C105-12, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20943960

RESUMO

LL-37 peptide is a multifunctional host defense molecule essential for normal immune responses to infection or tissue injury. In this study we assess the impact of LL-37 on endothelial stiffness and barrier permeability. Fluorescence microscopy reveals membrane localization of LL-37 after its incubation with human umbilical vein endothelial cells (HUVECs). A concentration-dependent increase in stiffness was observed in HUVECs, bovine aortic endothelial cells (BAECs), human pulmonary microvascular endothelial cells, and mouse aorta upon LL-37 (0.5-5 µM) addition. Stiffening of BAECs by LL-37 was blocked by P2X7 receptor antagonists and by the intracellular Ca²(+) chelator BAPTA-AM. Increased cellular stiffness correlated with a decrease in permeability of HUVEC cell monolayers after LL-37 addition compared with nontreated cells, which was similar to the effect observed upon treatment with sphingosine 1-phosphate, and both treatments increased F-actin content in the cortical region of the cells. These results suggest that the antiinflammatory effect of LL-37 at the site of infection or injury involves an LL-37-mediated increase in cell stiffening that prevents increased pericellular permeability. Such a mechanism may help to maintain tissue fluid homeostasis.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Células Endoteliais/citologia , Células Endoteliais/fisiologia , Actinas/fisiologia , Junções Aderentes/fisiologia , Animais , Aorta/efeitos dos fármacos , Bovinos , Membrana Celular , Células Cultivadas , Citoesqueleto/fisiologia , Humanos , Camundongos , Permeabilidade/efeitos dos fármacos , Catelicidinas
7.
Hepatogastroenterology ; 57(98): 367-71, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20583445

RESUMO

BACKGROUND/AIMS: Helicobacter pylori resides primarily in the gastric mucus layer composed of carbohydrate-rich glycoproteins, mucins. Carbohydrates of the secretory MUC 5AC mucin are one of the proved receptors for H. pylori adhesins. A participation of the membrane-associated MUC 1 in the mechanism of infection is also suggested. The main aim of the study was to support the participation of the membrane associated MUC 1 mucin in the mechanism of infection. METHODOLOGY: 13 gastric juices were included in the study. The presence of MUC 5AC and MUC 1 mucins as well as H. pylori bindings were performed using ELISA tests. RESULTS: MUC 1 and MUC 5AC mucins were present in all the examined juices. H. pylori adhered to both glycoproteins. CONCLUSIONS: H. pylori bind to the secretory MUC 5AC mucin as well as to the epithelial MUC 1. This supports the idea that the membrane-associated mucin is involved in the mechanism of H. pylori infection.


Assuntos
Suco Gástrico/metabolismo , Infecções por Helicobacter/metabolismo , Helicobacter pylori/metabolismo , Mucina-5AC/metabolismo , Mucina-1/metabolismo , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
PLoS One ; 5(4): e10380, 2010 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-20454462

RESUMO

BACKGROUND: Protein distribution profiles along the human intestinal tract of transporters involved in the absorption of cholesterol and long-chain fatty acids (LCFA) have been scarcely evaluated. METHODOLOGY/PRINCIPAL FINDINGS: In post-mortem samples from 11 subjects, intestinal transporter distribution profiles were determined via Western Blot. Differences in transporter protein levels were statistically tested using ANOVA and Tukey's Post Hoc comparisons. Levels in all segments were expressed relative to those in duodenum. Except for ABCG5 and FATP4, levels (mean+/-SEM) were the highest in the ileum. For ABCA1, ileal levels (1.80+/-0.26) differed significantly from those in duodenum (P = 0.049) and proximal colon (0.92+/-0.14; P = 0.029). ABCG8 levels in ileum (1.91+/-0.30) differed from those in duodenum (P = 0.041) and distal colon (0.84+/-0.22; P = 0.010) and jejunum (1.64+/-0.26) tended to be higher than distal colon (0.84+/-0.22; P = 0.087). Ileal NPC1L1 levels (2.56+/-0.51) differed from duodenum levels (P = 0.019) and from distal colon (1.09+/-0.22; P = 0.030). There was also a trend (P = 0.098) for higher jejunal (2.23+/-0.37) than duodenal NPC1L1 levels. The levels of ABCG5 did not correlate with those of ABCG8. FAT/CD36 levels in ileum (2.03+/-0.42) differed from those in duodenum (P = 0.017), and proximal and distal colon (0.89+/-0.13 and 0.97+/-0.15 respectively; P = 0.011 and P = 0.014). FABPpm levels in ileum (1.04+/-0.13) differed from proximal (0.64+/-0.07; P = 0.026) and distal colon (0.66+/-0.09; P = 0.037). CONCLUSIONS/SIGNIFICANCE: The distribution profiles showed a bell-shape pattern along the GI-tract with the highest levels in ileum for ABCA1, ABCG8, NPC1L1, FATCD36 and FABPm, suggesting a prominent role for ileum in transporter-mediated uptake of cholesterol and LCFAs.


Assuntos
Intestinos/química , Proteínas de Membrana Transportadoras/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Colesterol/metabolismo , Proteínas de Transporte de Ácido Graxo/análise , Ácidos Graxos/metabolismo , Feminino , Expressão Gênica , Humanos , Íleo/química , Íleo/metabolismo , Absorção Intestinal , Mucosa Intestinal/metabolismo , Masculino , Pessoa de Meia-Idade
9.
Antimicrob Agents Chemother ; 54(6): 2525-33, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20308375

RESUMO

The rising number of antibiotic-resistant bacterial strains represents an emerging health problem that has motivated efforts to develop new antibacterial agents. Endogenous cationic antibacterial peptides (CAPs) that are produced in tissues exposed to the external environment are one model for the design of novel antibacterial compounds. Here, we report evidence that disubstituted dexamethasone-spermine (D2S), a cationic corticosteroid derivative initially identified as a by-product of synthesis of dexamethasone-spermine (DS) for the purpose of improving cellular gene delivery, functions as an antibacterial peptide-mimicking molecule. This moiety exhibits bacterial killing activity against clinical isolates of Staphylococcus aureus, Pseudomonas aeruginosa present in cystic fibrosis (CF) sputa, and Pseudomonas aeruginosa biofilm. Although compromised in the presence of plasma, D2S antibacterial activity resists the proteolytic activity of pepsin and is maintained in ascites, cerebrospinal fluid, saliva, and bronchoalveolar lavage (BAL) fluid. D2S also enhances S. aureus susceptibility to antibiotics, such as amoxicillin (AMC), tetracycline (T), and amikacin (AN). Inhibition of interleukin-6 (IL-6) and IL-8 release from lipopolysaccharide (LPS)- or lipoteichoic acid (LTA)-treated neutrophils in the presence of D2S suggests that this molecule might also prevent systemic inflammation caused by bacterial wall products. D2S-mediated translocation of green fluorescent protein (GFP)-labeled glucocorticoid receptor (GR) in bovine aorta endothelial cells (BAECs) suggests that some of its anti-inflammatory activities involve engagement of glucocorticoid receptors. The combined antibacterial and anti-inflammatory activities of D2S suggest its potential as an alternative to natural CAPs in the prevention and treatment of some bacterial infections.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Dexametasona/análogos & derivados , Espermina/análogos & derivados , Animais , Antibacterianos/química , Anti-Inflamatórios/química , Peptídeos Catiônicos Antimicrobianos , Infecções Bacterianas/tratamento farmacológico , Biofilmes/efeitos dos fármacos , Catelicidinas/química , Catelicidinas/farmacologia , Bovinos , Células Cultivadas , Dexametasona/química , Dexametasona/farmacologia , Desenho de Fármacos , Humanos , Técnicas In Vitro , Interleucinas/biossíntese , Macrófagos/efeitos dos fármacos , Macrófagos/fisiologia , Testes de Sensibilidade Microbiana , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Fagocitose/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Receptores de Glucocorticoides/efeitos dos fármacos , Espermina/química , Espermina/farmacologia , Staphylococcus aureus/efeitos dos fármacos
10.
BMC Microbiol ; 9: 187, 2009 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-19728885

RESUMO

BACKGROUND: The worldwide appearance of drug-resistant strains of H. pylori motivates a search for new agents with therapeutic potential against this family of bacteria that colonizes the stomach, and is associated with adenocarcinoma development. This study was designed to assess in vitro the anti-H. pylori potential of cathelicidin LL-37 peptide, which is naturally present in gastric juice, its optimized synthetic analog WLBU2, and the non-peptide antibacterial agent ceragenin CSA-13. RESULTS: In agreement with previous studies, increased expression of hCAP-18/LL-37 was observed in gastric mucosa obtained from H. pylori infected subjects. MBC (minimum bactericidal concentration) values determined in nutrient-containing media range from 100-800 microg/ml for LL-37, 17.8-142 microg/ml for WLBU2 and 0.275-8.9 microg/ml for ceragenin CSA-13. These data indicate substantial, but widely differing antibacterial activities against clinical isolates of H. pylori. After incubation in simulated gastric juice (low pH with presence of pepsin) CSA-13, but not LL-37 or WLBU2, retained antibacterial activity. Compared to LL-37 and WLBU2 peptides, CSA-13 activity was also more resistant to inhibition by isolated host gastric mucins. CONCLUSION: These data indicate that cholic acid-based antimicrobial agents such as CSA-13 resist proteolytic degradation and inhibition by mucin and have potential for treatment of H. pylori infections, including those caused by the clarithromycin and/or metronidazole-resistant strains.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Esteroides/farmacologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Linhagem Celular Tumoral , Suco Gástrico/microbiologia , Mucosa Gástrica/metabolismo , Infecções por Helicobacter/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Esteroides/metabolismo , Catelicidinas
11.
Clin Biochem ; 42(1-2): 72-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18955039

RESUMO

OBJECTIVES: To evaluate the differences in glycoforms of ascitic fluids which can be considered as useful in discrimination between benign and malignant patients. DESIGN AND METHODS: The investigations were carried out on 17 benign and 13 malignant patients. To obtain high molecular weight material, gel exclusion chromatography was applied. To evaluate the relative amounts of different glycoforms, ELISA tests with biotinylated lectins were used. RESULTS: The fucosylation pattern was found to be similar in malignant and benign group. Fucose linked by alpha 1-6 bond was the most abundant structure. Sialylation was found to be more typical for malignant patients. Alpha 2-6 bond was observed on higher level than alpha 2-3 linkage. T and Tn antigens were present on rather low level with a slight prevalence of T antigen in malignant group. The glycoforms recognized by DSA lectin were more numerous in benign patients. CONCLUSIONS: The evaluation of the level of some ascitic fluids glycoforms can be useful in differentiation between malignant and benign diseases.


Assuntos
Líquido Ascítico/química , Fucose/química , Neoplasias/química , Antígenos Glicosídicos Associados a Tumores/química , Antígenos Virais de Tumores/química , Ensaio de Imunoadsorção Enzimática , Feminino , Glicosilação , Humanos , Lectinas/química , Masculino , Mucina-1/química
12.
Hepatogastroenterology ; 55(86-87): 1887-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19102415

RESUMO

BACKGROUND/AIMS: Helicobacter pylori that resides in the gastric mucus layer is the major etiological factor in gastritis, gastric ulcers and carcinomas. Among others, carbohydrate structures of MUC 1 mucin are also considered by some authors as being important in the mechanism of infection. The main aim of our study was to establish whether Helicobacter pylori treatment has any influence on the level of soluble form of MUC 1 mucin in gastric juice. METHODOLOGY: We examined two groups of Helicobacter pylori infected patients. The first group was treated with omeprazole (at the end of the therapy the bacterium was still present). The second group was treated with omeprazole and antibiotics, and the bacterium eradication was confirmed. MUC 1 mucin was determined by Western blotting technique. RESULTS: Before the therapy, the level of MUC 1 was found to be low in almost all cases, while at the end of the treatment in both groups of patients an increase of MUC 1 mucin was observed. CONCLUSIONS: Our results can confirm the thesis that Helicobacter pylori inhibits the expression of MUC 1 mucin on cell membranes.


Assuntos
Suco Gástrico/química , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Mucina-1/análise , Amoxicilina/uso terapêutico , Infecções por Helicobacter/metabolismo , Humanos , Omeprazol/uso terapêutico
13.
J Immunol ; 181(7): 4936-44, 2008 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-18802097

RESUMO

The various functions of gelsolin in extracellular compartments are not yet clearly defined but include actin scavenging and antiinflammatory effects. Gelsolin was recently reported to bind endotoxin (LPS) from various Gram-negative bacteria with high affinity. In this study we investigate whether gelsolin also interacts with bacterial wall molecules of Gram-positive bacteria such as lipoteichoic acid (LTA) and whether gelsolin's interaction with bacterial lipids from Gram-negative or Gram-positive bacteria affects their cellular inflammatory responses. A peptide based on the PPI binding site of gelsolin (160-169) binds purified LTA at the same molecular ratio that it binds phosphatidylinositol 4,5-bisphosphate. The OD of recombinant human plasma gelsolin was found to decrease following the addition of purified LTA, and the binding of gelsolin to LTA inhibits F-actin depolymerization by gelsolin. Simultaneously, the ability of LTA to activate translocation of NF-kappaB, E-selectin expression, and adhesion of neutrophils to LTA-treated human aortic endothelial cells was compromised by gelsolin. Gelsolin was able to partially inhibit LPS- or LTA-induced release of IL-8 from human neutrophils but was unable to prevent Gram-positive Bacillus subtilis or Gram-negative Pseudomonas aeruginosa growth and had no effect on the antibacterial activity of the cathelicidin-derived antibacterial peptide LL37. These data suggest that extracellular gelsolin is involved in the host immune recognition of LTA or LPS following release of these molecules from the bacterial outer membrane during cell division or attack by drugs and immune components.


Assuntos
Parede Celular/imunologia , Líquido Extracelular/metabolismo , Gelsolina/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/metabolismo , Neutrófilos/patologia , Staphylococcus aureus/imunologia , Ácidos Teicoicos/metabolismo , Actinas/antagonistas & inibidores , Actinas/metabolismo , Adesão Celular/imunologia , Parede Celular/metabolismo , Parede Celular/patologia , Células Cultivadas , Selectina E/biossíntese , Selectina E/genética , Selectina E/metabolismo , Líquido Extracelular/citologia , Líquido Extracelular/imunologia , Gelsolina/antagonistas & inibidores , Gelsolina/síntese química , Humanos , Imunidade Celular , Mediadores da Inflamação/antagonistas & inibidores , Interleucina-8/antagonistas & inibidores , Interleucina-8/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Neutrófilos/metabolismo , Neutrófilos/microbiologia , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/metabolismo , Ligação Proteica/imunologia , Staphylococcus aureus/metabolismo , Ácidos Teicoicos/antagonistas & inibidores
14.
J Antimicrob Chemother ; 62(2): 329-35, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18456648

RESUMO

OBJECTIVES: Cationic antimicrobial peptides (CAPs) are the effector molecules of innate immunity, similar in potency to classic antibiotics that function in the first-line of defence against infectious agents. The purpose of this study was to investigate the effects of negatively charged mucins on the antibacterial activity of the positively charged cathelicidin LL-37 peptide, its synthetic analogue WLBU2 and the antimicrobial cationic steroid CSA-13. METHODS: Mucin, DNA, F-actin and hCAP-18/LL-37 in saliva samples were evaluated by microscopy or immunoblotting. Bacterial killing assays and determination of MICs were used to determine bactericidal activity. Binding of rhodamine-B-labelled LL-37 peptide to mucin was fluorimetrically assessed. RESULTS: Microscopic evaluation of saliva after addition of rhodamine-B-labelled LL-37 showed localization similar to that observed after the addition of a specific mucin-binding lectin. Immunoblotting confirmed the presence of hCAP-18/LL-37 in saliva samples and LL-37 peptide bound to isolated submaxillary gland mucin-coated plates. Mucin/LL-37 binding was partially prevented by treatment of mucin with neuraminidase, indicating involvement of sialic acid moieties. Decreased LL-37 and WLBU2 antibacterial activity was observed in the presence of mucin or dialysed human saliva, whereas CSA-13 antibacterial activity was significantly resistant to inhibition by mucins. CONCLUSIONS: This study shows that the antibacterial LL-37 peptide and its synthetic analogue WLBU2 are inhibited by salivary mucin and that the cationic steroid CSA-13 retains most of its function in the presence of an equal amount of mucin or saliva.


Assuntos
Antibacterianos/antagonistas & inibidores , Peptídeos Catiônicos Antimicrobianos/antagonistas & inibidores , Mucinas/metabolismo , Saliva/química , Esteroides/antagonistas & inibidores , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Contagem de Colônia Microbiana , Humanos , Immunoblotting , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Saliva/metabolismo , Esteroides/farmacologia , Catelicidinas
15.
Dig Dis Sci ; 53(10): 2641-5, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18409003

RESUMO

Helicobacter pylori is considered as a causative agent of gastritis, duodenal and gastric ulcers, and gastric cancer. During inflammation, association of the pathogen of gastric epithelial cells and mucins is considered important. It was postulated that Lewis b structures of secretory MUC 5AC mucin can be a receptor for the bacterium. Some authors also suggest that epithelial MUC 1 mucin may be implicated in the mechanism of infection. The main aim of our work was to support this last suggestion by evaluation of the possible changes in MUC 1 and Lewis a and b levels in gastric juice before and at the end of eradication treatment. The gastric juices of ten examined patients were chromatographed on a Sepharose 4 B column, electrotransferred on Immobilon P membranes, and assessed for MUC 1 and Lewis a and b structures using monoclonal antibodies. In 90% of examined patients, higher amounts of MUC 1 mucin were observed at the end of eradication treatment. Similar results for Lewis a and b structures were found. In the case of MUC 1 and Lewis b, the differences were statistically significant. Helicobacter pylori influences expression of the soluble form of MUC 1 mucin and Lewis a and b structures present in gastric juice.


Assuntos
Antibacterianos/uso terapêutico , Suco Gástrico/metabolismo , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/metabolismo , Helicobacter pylori/efeitos dos fármacos , Antígenos do Grupo Sanguíneo de Lewis/metabolismo , Mucina-1/metabolismo , Adulto , Amoxicilina/farmacologia , Amoxicilina/uso terapêutico , Antibacterianos/farmacologia , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Feminino , Suco Gástrico/microbiologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Infecções por Helicobacter/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Omeprazol/farmacologia , Omeprazol/uso terapêutico
16.
Med Dosw Mikrobiol ; 59(1): 51-8, 2007.
Artigo em Polonês | MEDLINE | ID: mdl-17601031

RESUMO

A total of 154 adult patients with dyspeptic symptoms were studied. In case of 115 (74,68%) persons Helicobacter pylori infection was detected, taking into consideration positive results in a rapid urease test and histological examination and presence of antibodies in the serum. In 69,6% predominated high (> 72 IU/ml) level specific anty-H. pylori antibodies. In stool, antigen H. pylori was detected in 100 (64,9%) samples. In 137 cases were obtained results, this same like results of three early tests. Senitivity and specificity of HpSA test were 86,21% and 98,18%, respectively. It was significant (13,91%) percenage of false negative results.


Assuntos
Antígenos de Bactérias/análise , Dispepsia/microbiologia , Fezes/microbiologia , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Adulto , Idoso , Reações Falso-Negativas , Feminino , Infecções por Helicobacter/complicações , Helicobacter pylori/imunologia , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Helicobacter ; 12(1): 63-7, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17241303

RESUMO

BACKGROUND: Helicobacter pylori eradication from the oral cavity is more difficult than from the stomach. Thus, if the bacterium survives the antibacterial therapy in the oral cavity, it would be able to re-infect the stomach within a few weeks. Since oral health status could correspond to oral infection with H. pylori, the aim of the study was to determine whether oral health and oral hygiene practices affect the efficacy of H. pylori eradication from the stomach. MATERIAL AND METHODS: The study was performed in 137 patients with peptic ulcer who had undergone a 7-day course of eradication treatment with one of two sets of drugs: 1, omeprazole, amoxicillin, and tinidazole or 2, omeprazole, clarithromycin, and tinidazole. The efficacy of H. pylori eradication from the stomach was evaluated at the second gastroscopy 4 weeks after cessation of eradication therapy by means of two methods: rapid urease test and histology. The examination of natural dentition and prosthetic restorations as well as the assessment of hygienic procedures referring to natural dentition and dentures accompanied the second gastroscopy. RESULTS: No association was found between the efficacy of H. pylori eradication from the stomach and the number of natural teeth, decayed teeth, use of dentures, debris index, or periodontal index. However, an association between eradication success and some oral hygiene procedures were noted. Unexpectedly, in patients treated with omeprazole, amoxicillin and tinidazole, the removal of dental prosthesis for the night and brushing the natural teeth twice a day or more reduced the efficacy of H. pylori eradication from the stomach. CONCLUSIONS: Oral health and oral hygiene practices seem unlikely to increase the efficacy of H. pylori eradication from the stomach.


Assuntos
Anti-Infecciosos/uso terapêutico , Antiulcerosos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Mucosa Bucal/microbiologia , Omeprazol/uso terapêutico , Higiene Bucal , Úlcera Péptica/tratamento farmacológico , Tinidazol/uso terapêutico , Amoxicilina/uso terapêutico , Antibacterianos/uso terapêutico , Claritromicina/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/microbiologia , Resultado do Tratamento
18.
Artigo em Inglês | MEDLINE | ID: mdl-15184853

RESUMO

OBJECTIVE: Oral health status may play a role in Helicobacter pylori eradication. Because adequate secretion of saliva promotes oral health, the aim of the study was to assess the effect of salivary secretion on the efficacy of H pylori eradication from the stomach. STUDY DESIGN: The study involved 90 H pylori-positive subjects with duodenal ulcer (68 men, 22 women, aged 20-70 years) in whom saliva was collected under basal conditions for 45 min before antibacterial treatment began. They received no drugs for at least 3 days prior to saliva collection. A 7-day course of either of 2 eradication regimens--omeprazole, amoxicillin, and tinidazole (OAT); or omeprazole, amoxicillin, and clarithromycin (OAC)--was used. The efficacy of eradication therapy was evaluated 30 days after its completion. RESULTS: The efficacy of H pylori eradication from the stomach (per protocol analysis) was 77.5% in the group of subjects treated with OAT and 81.6% with OAC. Combined analysis of both groups (OAT+OAC) showed reduced salivary secretion in subjects with eradication failure (0.395 +/- 0.266 vs 0.25 +/- 0.176 mL/min, P=.042). A similar outcome was obtained when the OAT group was analyzed separately (0.436 +/- 0.316 vs 0.211 +/- 0.216 mL/min, P=.022), but in the OAC group the difference was not significant. In the combined analysis, the efficacy of eradication therapy was lower in women than in men (52.9% vs 86.9%, P=.005). In women, it corresponded to salivary secretion (successful eradication 0.337 +/- 0.133 mL/min, unsuccessful eradication 0.180 +/- 0.144 mL/min, P=.043); whereas in men, the difference was not significant (successful eradication 0.405 +/- 0.282 mL/min, unsuccessful eradication 0.321 +/- 0.186 mL/min). CONCLUSION: Low salivary secretion may contribute to the decrease in efficacy of H pylori eradication from the stomach, at least in subjects treated with certain drug regimens.


Assuntos
Antibacterianos/uso terapêutico , Úlcera Duodenal/microbiologia , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Saliva/metabolismo , Adulto , Idoso , Amoxicilina/uso terapêutico , Antiulcerosos/uso terapêutico , Claritromicina/uso terapêutico , Úlcera Duodenal/tratamento farmacológico , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Boca/microbiologia , Omeprazol/uso terapêutico , Saliva/efeitos dos fármacos , Fatores Sexuais , Estômago/microbiologia , Tinidazol/uso terapêutico , Resultado do Tratamento
19.
Clin Biochem ; 36(7): 529-35, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14563446

RESUMO

OBJECTIVES: Intestinal-type fatty acid-binding protein (I-FABP) has been proposed as plasma marker for the detection of acute intestinal injury. However, intestinal mucosa also expresses liver-type FABP (L-FABP). We have investigated the tissue distribution of I-FABP and L-FABP in segments of the human intestine along the duodenal to colonal axis and the potential of both proteins to serve as plasma marker for the diagnosis of intestinal injury. DESIGN AND METHODS: I-FABP and L-FABP were measured with specific immunoassays in autopsy samples of the intestine (duodenum, jejunum, ileum and colon) of 23 subjects and in plasma samples from patients (n = 51) with intestinal and/or hepatic disease. Plasma reference values were established in normal healthy individuals (n = 92). RESULTS: The I-FABP tissue contents in duodenum, jejunum, ileum, proximal colon and distal colon amounted to 2.22, 4.79, 1.04, 0.27 and 0.25 mug/g ww, respectively. L-FABP tissue contents were markedly higher, amounting to 124 and 198 mug/g ww in duodenum and jejunum, and to 58, 26 and 44 mug/g ww in ileum, proximal colon and distal colon, respectively. Elevated plasma levels of both I-FABP and L-FABP were found in patients suffering from intestinal diseases, while only L-FABP was increased in cases of purely hepatocellular injury. CONCLUSIONS: I-FABP and L-FABP show a similar pattern of tissue distribution along the duodenal to colonal axis with highest tissue contents found in the jejunum but in each intestinal segment a >40-fold higher content of L-FABP than of I-FABP. Accordingly, besides I-FABP, also L-FABP is a useful plasma marker for the detection of intestinal injury, especially in patients undergoing intestinal surgery.


Assuntos
Proteínas de Transporte/análise , Intestinos/química , Fígado/química , Proteínas Supressoras de Tumor , Adulto , Idoso , Proteínas de Transporte/sangue , Ensaio de Imunoadsorção Enzimática , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Feminino , Saúde , Humanos , Enteropatias/diagnóstico , Enteropatias/metabolismo , Enteropatias/cirurgia , Intestinos/lesões , Intestinos/patologia , Intestinos/cirurgia , Masculino , Pessoa de Meia-Idade , Valores de Referência , Caracteres Sexuais , Fatores de Tempo
20.
Med Sci Monit ; 9(1): CR24-8, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12552246

RESUMO

BACKGROUND: Adenosine deaminase is an enzyme which is postulated to have a role in the generation of gastric mucosal inflammation. The aim of our study was to determine and compare adenosine deaminase activity in the gastric mucosa of patients with chronic gastritis developed in partially resected and intact stomachs. MATERIAL/METHODS: 182 patients were studied, 102 non-operated and 80 after distal gastric resection. Biopsy specimens were taken endoscopically from the gastric mucosa 2 cm proximal to the stoma or corresponding upper third of the intact stomach. Gastritis was classified according to the Sydney system. The activity of adenosine deaminase in the mucosal homogenates was measured by determination of ammonia liberated from the substrate and expressed in nmol NH3/mg protein/min. RESULTS: Adenosine deaminase activity was lower in partially resected than in intact stomachs, regardless of Helicobacter pylori infection. While no difference was found in adenosine deaminase activity between Billroth I and Billroth II procedures in subjects without H. pylori infection, the activity was lower in those with Billroth II procedure in the presence of H. pylori infection. As the severity of gastritis increased, enzyme activity decreased in the mucosa of the intact stomach, but was not significantly altered in the mucosa of the gastric remnant. CONCLUSIONS: Adenosine deaminase activity differs in intact and partially resected stomachs, but it does not appear to be a factor promoting chronic gastritis.


Assuntos
Adenosina Desaminase/metabolismo , Gastrite/enzimologia , Mucosa/enzimologia , Biópsia , Endoscopia , Gastrite/microbiologia , Helicobacter pylori/metabolismo , Humanos , Inflamação , Estômago/enzimologia , Estômago/microbiologia , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/microbiologia , Úlcera/enzimologia , Úlcera/microbiologia
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