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1.
Am J Physiol Gastrointest Liver Physiol ; 321(5): G461-G476, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34431405

RESUMEN

Multiple theories have been proposed describing the pathogenic mechanisms of Helicobacter pylori (H. pylori)-associated gastric motility disorders. We assessed ex vivo pyloric activity in H. pylori-infected rats, and tried to explore the associated ghrelin hormone alteration and pyloric fibrogenesis. In addition, miR-1 was assessed in pyloric tissue samples, being recently accused of having a role in smooth muscle dysfunction. Ninety adult male Wistar albino rats were assigned into nine groups: 1) control group, 2) sterile broth (vehicle group), 3) amoxicillin control, 4) omeperazole control, 5) clarithromycin control, 6) triple therapy control, 7) H. pylori- group, 8) H. pylori-clarithromycin group, and 9) H. pylori-triple therapy group. Urease enzyme activity was applied as an indicator of H. pylori infection. Ex vivo pyloric contractility was evaluated. Serum ghrelin was assessed, and histological tissue evaluation was performed. Besides, pyloric muscle miR-1 expression was measured. The immunological epithelial to mesenchymal transition (EMT) markers; transforming growth factor ß (TGFß), α-smooth muscle actin (α-SMA), and E-cadherin-3 were also evaluated. By H. pylori infection, a significant (P < 0.001) reduced pyloric contractility index was recorded. The miR-1 expression was decreased (P < 0.001) in the H. pylori-infected group, associated with reduced serum ghrelin, elevated TGFß, and α-SMA levels and reduced E-cadherin levels. Decreased miR-1 and disturbed molecular pattern were improved by treatment. In conclusion, H. pylori infection was associated with reduced miR-1, epithelial to mesenchymal transition, and pyloric hypomotility. The miR-1 may be a target for further studies to assess its possible involvement in H. pylori-associated pyloric dysfunction, which might help in the management of human H. pylori manifestations and complications.NEW & NOTEWORTHY This work is investigating functional, histopathological, and molecular changes underlying Helicobacter pylori hypomotility and is correlating these with miR-1, whose disturbance is supposed to be involved in smooth muscle dysfunction and cell proliferation according to literature. Epithelial to mesenchymal transition and reduced ghrelin hormone may contribute to H. pylori infection-associated hypomotility. H. pylori infection was associated with reduced pyloric miR-1 expression. Targeting miR-1 could be valuable in the clinical management of pyloric hypofunction.


Asunto(s)
Transición Epitelial-Mesenquimal , Motilidad Gastrointestinal , Infecciones por Helicobacter/microbiología , Helicobacter pylori/patogenicidad , Músculo Liso/microbiología , Píloro/microbiología , Gastropatías/microbiología , Actinas/metabolismo , Animales , Antibacterianos/farmacología , Cadherinas/metabolismo , Modelos Animales de Enfermedad , Quimioterapia Combinada , Transición Epitelial-Mesenquimal/efectos de los fármacos , Motilidad Gastrointestinal/efectos de los fármacos , Ghrelina/sangre , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/fisiopatología , Masculino , MicroARNs/genética , MicroARNs/metabolismo , Músculo Liso/efectos de los fármacos , Músculo Liso/metabolismo , Músculo Liso/fisiopatología , Inhibidores de la Bomba de Protones/farmacología , Píloro/efectos de los fármacos , Píloro/metabolismo , Píloro/fisiopatología , Ratas Wistar , Gastropatías/tratamiento farmacológico , Gastropatías/metabolismo , Gastropatías/fisiopatología , Factor de Crecimiento Transformador beta/metabolismo
2.
Biomed Res Int ; 2019: 1948519, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30723734

RESUMEN

Our previous study showed that neonatal S. pneumoniae infection aggravated airway inflammation and airway hyperresponsiveness (AHR) in an OVA-induced allergic asthma model. As airway smooth muscle (ASM) plays a pivotal role in AHR development, we aim to investigate the effects of neonatal S. pneumoniae pneumonia on ASM structure and AHR development. Non-lethal neonatal pneumonia was established by intranasally infecting 1-week-old BALB/C mice with the S. pneumoniae strain D39. Five weeks after infection, the lungs were collected to assess the levels of α-SMA and the contractile proteins of ASM. Our results indicate that neonatal S. pneumoniae pneumonia significantly increased adulthood lung α-SMA and SMMHC proteins production and aggravated airway inflammatory cells infiltration and cytokines release. In addition, the neonatal S. pneumoniae pneumonia group had significantly higher Penh values compared to the uninfected controls. These data suggest that neonatal S. pneumoniae pneumonia promoted an aberrant ASM phenotype and AHR development in mice model.


Asunto(s)
Pulmón/metabolismo , Músculo Liso/metabolismo , Neumonía/genética , Hipersensibilidad Respiratoria/genética , Actinas/genética , Animales , Animales Recién Nacidos , Líquido del Lavado Bronquioalveolar/microbiología , Modelos Animales de Enfermedad , Humanos , Pulmón/microbiología , Pulmón/patología , Ratones , Músculo Liso/microbiología , Músculo Liso/patología , Fenotipo , Neumonía/complicaciones , Neumonía/microbiología , Neumonía/patología , Hipersensibilidad Respiratoria/complicaciones , Hipersensibilidad Respiratoria/microbiología , Hipersensibilidad Respiratoria/patología , Streptococcus pneumoniae/patogenicidad
3.
J Pathol ; 240(1): 15-24, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27218225

RESUMEN

Despite antibiotic treatment, up to 40% of patients have impaired fertility after epididymitis due to serovars of Escherichia coli, a frequent pathogen. The reasons for infertility are unclear, but it may result from epididymal duct obstruction. To determine whether E. coli infection of the epididymis causes obstruction due to fibrosis, and to identify the key mediators, tissues from patients with epididymitis were assessed. Additionally, epididymitis was induced with uropathogenic E. coli (UPEC) or commensal serovars in wild-type and MyD88(-/-) mice, which are relatively unresponsive to bacterial pathogens. Epididymal organ cultures were treated with activin A and bacteria and their histology and levels of cytokines and fibrosis markers were analysed. Patients with epididymitis showed severe fibrosis of the epididymal duct. In mice, UPEC infection also caused fibrosis and ductal obstruction in the cauda epididymis. Levels of mRNA for fibrotic markers (α-smooth muscle actin, fibronectin) and cytokines (activin A, TNFα, IL-1α, IL-1ß, IL-6) and total collagen levels were significantly elevated. This fibrotic response was blunted by the loss of MyD88. Activin A induced fibrosis in cultured epididymis, which was inhibited by the activin-binding protein follistatin. In summary, bacterial epididymitis causes fibrosis and obstruction. The milder tissue damage in Myd88(-/-) UPEC epididymitis highlights the importance of the host response to infection in causing epididymal damage. Elevated levels of activin A in vivo and fibrotic remodelling elicited by activin A in vitro indicate that this cytokine is a potential target for supplementary treatment to antibiotic therapy. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Epidídimo/microbiología , Epididimitis/microbiología , Infecciones por Escherichia coli/patología , Músculo Liso/microbiología , Escherichia coli Uropatógena , Actinas/metabolismo , Anciano , Animales , Colágeno/metabolismo , Citocinas/metabolismo , Epidídimo/metabolismo , Epidídimo/patología , Epididimitis/metabolismo , Epididimitis/patología , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Fibronectinas/metabolismo , Fibrosis/metabolismo , Fibrosis/microbiología , Fibrosis/patología , Humanos , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Músculo Liso/metabolismo , Músculo Liso/patología , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo
4.
PLoS One ; 9(10): e110519, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25334003

RESUMEN

BACKGROUND: A number of studies have revealed a link between chronic periodontitis and cardiovascular disease in obese patients. However, there is little information about the influence of periodontitis-associated bacteria, Porphyromonas gingivalis (Pg), on pathogenesis of atherosclerosis in obesity. METHODS: In vivo experiment: C57BL/6J mice were fed with a high-fat diet (HFD) or normal chow diet (CD), as a control. Pg was infected from the pulp chamber. At 6 weeks post-infection, histological and immunohistochemical analysis of aortal tissues was performed. In vitro experiment: hTERT-immortalized human umbilical vein endothelial cells (HuhT1) were used to assess the effect of Pg/Pg-LPS on free fatty acid (FFA) induced endothelial cells apoptosis and regulation of cytokine gene expression. RESULTS: Weaker staining of CD31 and increased numbers of TUNEL positive cells in aortal tissue of HFD mice indicated endothelial injury. Pg infection exacerbated the endothelial injury. Immunohistochemically, Pg was detected deep in the smooth muscle of the aorta, and the number of Pg cells in the aortal wall was higher in HFD mice than in CD mice. Moreover, in vitro, FFA treatment induced apoptosis in HuhT1 cells and exposure to Pg-LPS increased this effect. In addition, Pg and Pg-LPS both attenuated cytokine production in HuhT1 cells stimulated by palmitate. CONCLUSIONS: Dental infection of Pg may contribute to pathogenesis of atherosclerosis by accelerating FFA-induced endothelial injury.


Asunto(s)
Periodontitis/microbiología , Animales , Aorta/microbiología , Aorta/patología , Apoptosis/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Células Endoteliales de la Vena Umbilical Humana , Humanos , Lipopolisacáridos/toxicidad , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Músculo Liso/microbiología , Músculo Liso/patología , Palmitatos/toxicidad , Periodontitis/patología , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Porphyromonas gingivalis/aislamiento & purificación , Receptor Toll-Like 4/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia Arriba/efectos de los fármacos
5.
Neurogastroenterol Motil ; 25(12): 984-e777, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24118564

RESUMEN

BACKGROUND: Lactobacillus species might positively affect gastrointestinal motility. These Gram-positive bacteria bind Toll-like receptor 2 (TLR2) that elicits anti-inflammatory activity and exerts protective effects on damage induced by lipopolysaccharide (LPS). Whether such effect occurs in gastrointestinal smooth muscle has not been established yet. Aim of this study was to characterize the effects of Lactobacillus rhamnosus GG (LGG) and of supernatants harvested from LGG cultures on human colonic smooth muscle and to explore their protective activity against LPS-induced myogenic morpho-functional alterations. METHODS: The effects of LGG (ATCC 53103 strain) and of supernatants have been tested on both human colonic smooth muscle strips and isolated cells in the absence or presence of LPS obtained from a pathogenic strain of Escherichia coli. Their effects on myogenic morpho-functional properties, on LPS-induced NFκB activation, and on cytokine production have been evaluated. Toll-like receptor 2 expression has been analyzed by qPCR and flow cytometry. KEY RESULTS: Lactobacillus rhamnosus GG exerted negligible transient effects per se whereas it was capable of activating an intrinsic myogenic response counteracting LPS-induced alterations. In particular, both LGG and supernatants significantly reduced the LPS-induced morpho-functional alterations of muscle cells, i.e. cell shortening and inhibition of contractile response. They also hindered LPS-induced pro-inflammatory effects by decreasing pro-inflammatory transcription factor NFκB activation and pro-inflammatory cytokine IL-6 secretion, and restored the secretion levels of anti-inflammatory cytokine IL10. CONCLUSIONS & INFERENCES: Taken together these data demonstrate that LGG protects human colonic smooth muscle from LPS-induced myogenic damage and might be beneficial on intestinal motor disorders due to bacterial infection.


Asunto(s)
Colon/microbiología , Lacticaseibacillus rhamnosus , Lipopolisacáridos/toxicidad , Músculo Liso/microbiología , Probióticos/farmacología , Células Cultivadas , Colon/efectos de los fármacos , Motilidad Gastrointestinal , Humanos , Músculo Liso/efectos de los fármacos
6.
Gastroenterol Hepatol ; 34(7): 449-53, 2011.
Artículo en Español | MEDLINE | ID: mdl-21763037

RESUMEN

INTRODUCTION: Helicobacter species have recently been found to be associated with some diseases of the biliary tree but this relationship remains unclear and further studies are required. The aim of this study was to determine the presence of H. pylori-type bacteria in patients with a diagnosis of chronic cholecystitis through histopathological study of surgical gallbladder specimens. MATERIALS AND METHODS: Surgical gallbladder specimens from patients with a diagnosis of chronic cholecystitis were examined histopathologically. The macroscopic characteristics of the specimens were identified. Histopathological slices were stained with hematoxylin-eosin and Giemsa. RESULTS: Of the 68 patients who underwent cholecystectomy, 56 (81%) were women and 12 (19%) were men. The mean age was 39.56+11.94 years. H. pylori-type bacteria were found in 6%. CONCLUSIONS: The results of this study do not allow us to conclude that the presence of H. pylori-type bacteria is a major factor in the etiology and/or pathogenesis of chronic cholecystitis. In patients with chronic cholecystitis undergoing cholecystectomy included in the present study, the etiology of the disease may be more closely linked with the presence of gallstones.


Asunto(s)
Colecistitis/microbiología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Adulto , Colecistectomía , Colecistitis/patología , Colecistitis/cirugía , Colelitiasis/microbiología , Colelitiasis/cirugía , Colesterol/análisis , Enfermedad Crónica , Femenino , Fibrosis , Vesícula Biliar/química , Vesícula Biliar/microbiología , Vesícula Biliar/patología , Infecciones por Helicobacter/patología , Infecciones por Helicobacter/cirugía , Humanos , Hipertrofia , Masculino , Persona de Mediana Edad , Músculo Liso/microbiología , Músculo Liso/patología
8.
Int J Infect Dis ; 14 Suppl 3: e70-2, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20207571

RESUMEN

BACKGROUND: Leprosy is a chronic inflammatory disease caused by Mycobacterium leprae, which affects not only the peripheral nerves and skin, but also various internal viscera through hematogenous spread, especially in lepromatous cases. Histology in its own way plays a vital role, not only in classifying the established lesion, but also in confirming the clinical diagnosis. During the latent period of subclinical involvement, the apparently normal looking skin might also be undergoing some pathological changes. METHODS: We investigated skin biopsy material taken from 60 patients with clinically diagnosed leprosy at Subharti Hospital, Subharti Medical College, Meerut, India. Hematoxylin and eosin staining and Harada's modified allochrome method for acid-fast bacilli were applied for histological investigations. RESULTS: The pattern of leprosy among the patients was indeterminate in 25 cases (41.7%), tuberculoid in 14 (23.3%), borderline tuberculoid in six (10%), borderline leprosy in four (6.7%), borderline lepromatous in four (6.7%), and lepromatous leprosy in seven (11.7%). Changes were seen in the arrector pili muscle of normal appearing skin in all types of leprosy, but involvement was greater at the lepromatous end of the spectrum compared to the tuberculoid end. CONCLUSIONS: Results of this study revealed definitive histological changes in the arrector pili muscle in normal appearing skin. The presence of AFB is significant as far as dissemination and transmission of the disease is concerned.


Asunto(s)
Lepra/patología , Músculo Liso/patología , Piel/patología , Femenino , Humanos , India , Lepra/microbiología , Lepra Dimorfa/patología , Lepra Lepromatosa/patología , Lepra Tuberculoide/patología , Masculino , Músculo Liso/microbiología , Piel/microbiología
9.
Neurogastroenterol Motil ; 22(3): 341-e87, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19814773

RESUMEN

BACKGROUND Cystic fibrosis (CF) has multiple effects on the gastrointestinal system, including altered motility. The Cftr knockout mouse model of CF has impaired small intestinal transit but the mechanism is unknown. METHODS Behaviour of circular smooth muscle was studied in an organ bath. Expression levels of prostaglandin (PG) degradative genes were measured by quantitative RT-PCR, and PGE(2) levels were measured by enzyme immunoassay. KEY RESULTS Cystic fibrosis circular muscle activity was erratic and had variable frequency of contractions, as compared to WT. The CF tissue was non-responsive to cholinergic stimulation or direct KCl depolarization. PGE(2) and PGF(2alpha) are significantly elevated in the CF mouse small intestine, and we hypothesized these contribute to impaired smooth muscle activity. After inhibition of PG synthesis, the CF circular muscle exhibited greater cholinergic responsiveness, which was reversed by exogenous PGE(2). PGF(2alpha) enhanced activity of CF tissue only after inhibition of PG synthesis. The enteric microbiota was implicated in PGE(2)-mediated dysmotility because broad spectrum antibiotic treated WT mice, which have slowed transit, exhibit impaired circular muscle activity. This was accompanied by decreased expression of PG degradative genes and increased intestinal PGE(2) levels. Furthermore, administration of oral laxative, which eradicates bacterial overgrowth and improves transit in CF mice, increased expression of PG degradative genes, decreased PGE(2) levels, and improved CF muscle activity. CONCLUSIONS & INFERENCES These results suggest that the enteric microbiota modulates PGE(2) levels in a complex manner, which affects enteric smooth muscle activity and contributes to slower small intestinal transit in CF.


Asunto(s)
Fibrosis Quística/fisiopatología , Intestino Delgado/fisiopatología , Músculo Liso/fisiopatología , Análisis de Varianza , Animales , Antibacterianos/administración & dosificación , Fibrosis Quística/metabolismo , Fibrosis Quística/microbiología , Dinoprostona/metabolismo , Modelos Animales de Enfermedad , Femenino , Vaciamiento Gástrico/efectos de los fármacos , Tránsito Gastrointestinal/efectos de los fármacos , Tránsito Gastrointestinal/fisiología , Técnicas para Inmunoenzimas , Intestino Delgado/metabolismo , Intestino Delgado/microbiología , Masculino , Ratones , Ratones Endogámicos CFTR , Contracción Muscular/fisiología , Músculo Liso/metabolismo , Músculo Liso/microbiología
10.
Przegl Epidemiol ; 57(2): 255-62, 2003.
Artículo en Polaco | MEDLINE | ID: mdl-12910592

RESUMEN

In this study, using scanning and transmission electron microscope, we attempt to evaluate ultrastructural alterations of endothelial cells, macrophages and smooth muscles cells. The inflammatory process has an essential impact on the development of Chlamydia infection. Specimens from human carotid were obtained from patients who underwent endarterectomy. For examination under scanning and transmission electron microscope vessel sections were fixed in paraformaldehyde and glutaraldehyde. We analysed alterations of endothelial cells covering advanced atherosclerotic plaque in carotid using scanning electron microscope. Smooth muscle cells had undergone the heaviest proliferation among the cells on artery wall. In the tested material we detect diversified morphological forms of Chlamydia sp. We found that one of the pathogens that may lead to atherosclerotic lesions is Chlamydia pneumoniae.


Asunto(s)
Arterias Carótidas/microbiología , Arterias Carótidas/ultraestructura , Enfermedades de las Arterias Carótidas/microbiología , Enfermedades de las Arterias Carótidas/patología , Infecciones por Chlamydia/microbiología , Chlamydophila pneumoniae , Anciano , Endotelio Vascular/microbiología , Endotelio Vascular/ultraestructura , Femenino , Humanos , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Mitocondrias Musculares/microbiología , Mitocondrias Musculares/ultraestructura , Músculo Liso/microbiología , Músculo Liso/ultraestructura
11.
Respir Med ; 97(8): 933-8, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12924521

RESUMEN

It has been argued whether bronchiectasis is truly caused by MAC infection or just a predisposed condition in which MAC colonizes. Our present study was designed to evaluate the pathological findings of bronchiectases caused by Mycobacterium avium intracellulare complex (MAC) lung infection and to demonstrate MAC in the lesion of bronchiectases. A retrospective study was performed in nine cases with positive cultures for MAC in whom lung resections were performed. A determination of whether or not MAC caused pulmonary disease was made using the 1997 criteria required by the American Thoracic Society. In addition, MAC were cultured from all nine lung specimens. Pathological findings of bronchiectases were evaluated in these nine patients. Destruction of bronchial cartilage and smooth muscles layer, obstruction of airway by granulomas, and ulceration of bronchial mucosa were frequently observed. Our present study demonstrates that destruction of fundamental bronchial structure due to extensive granuloma formation throughout the airways was likely the main cause of bronchiectases in MAC infection.


Asunto(s)
Bronquiectasia/patología , Infección por Mycobacterium avium-intracellulare/patología , Adulto , Anciano , Bronquiectasia/microbiología , Cartílago/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Liso/microbiología , Complejo Mycobacterium avium , Infección por Mycobacterium avium-intracellulare/complicaciones , Estudios Retrospectivos
12.
Shock ; 19(4): 378-82, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12688551

RESUMEN

In the obstructed gut, nitric oxide (NO) may influence intestinal barrier function and translocation of bacteria. By using a novel experimental approach, we investigated the effect of supplementation and inhibition of NO synthesis on the time interval necessary for translocation of green fluorescent protein-transfected Escherichia coli (GFP-uv E. coli) in a rat model of small bowel obstruction. In anesthetized Wistar rats, 4 x 10(8) GFP-uv E. coli were administered into a reservoir of terminal ileum formed by ligature. Animals were randomized to receive either i.v. arginine (10 mg/kg), aminoguanidine (300 mg/kg), L-NAME (25 mg/kg), or saline (control). Translocation of GFP-uv E. coli was assessed using intravital video microscopy. Minimal transit time of translocation was measured as time from injection of GFP-uv E. coli into the gut lumen until bacteria were observed in the lamina submucosa and as time from injection of bacteria into the gut lumen until bacteria were observed in the lamina muscularis propria. Minimal transit times were expressed as mean +/- SD. Bacterial translocation into the submucosa and muscularis propria took 36 +/- 7 min and 81 +/- 9 min, respectively in control animals receiving saline. Aminoguanidine and L-NAME caused a marked delay of minimal transit time into the submucosa (63 +/- 5 min and 61 +/- 7 min, respectively; P < 0.05). Arginine significantly accelerated bacterial translocation into the muscularis propria (61 +/- 9 min, P < 0.05). GFP-uv E. coli were detected on frozen sections of small bowel, mesentery, liver, and spleen 2 h after GFP-uv E. coli administration in all animals. A marked upregulation of inducible NO synthase (NOS) in the obstructed bowel segment was demonstrated on immunohistochemistry. The assessment of a newly defined parameter, minimal bacterial transit time, may serve as an additional functional aspect of intestinal barrier function for pathophysiological and pharmacological studies. Aminoguanidine, L-NAME, and arginine were effective in influencing minimal transit time of E. coli during small bowel obstruction.


Asunto(s)
Arginina/farmacología , Traslocación Bacteriana/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Escherichia coli/fisiología , Guanidinas/farmacología , Enfermedades del Íleon/microbiología , Obstrucción Intestinal/microbiología , NG-Nitroarginina Metil Éster/farmacología , Donantes de Óxido Nítrico/farmacología , Óxido Nítrico/farmacología , Animales , Traslocación Bacteriana/fisiología , Escherichia coli/química , Genes Reporteros , Proteínas Fluorescentes Verdes , Enfermedades del Íleon/complicaciones , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/microbiología , Obstrucción Intestinal/complicaciones , Proteínas Luminiscentes/análisis , Proteínas Luminiscentes/genética , Masculino , Modelos Animales , Músculo Liso/efectos de los fármacos , Músculo Liso/microbiología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Ratas , Ratas Wistar , Factores de Tiempo , Transfección
13.
J Invertebr Pathol ; 82(3): 167-75, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12676553

RESUMEN

Spiroplasma kunkelii distribution and infection mechanisms in the intestines and Malpighian tubules of Dalbulus maidis were investigated by transmission electron microscopy. Spiroplasmas were found between microvilli and in endocytic vesicles of the midgut epithelium. At the basal part, cytoplasmic vesicles contained multiple spiroplasmas with tube-like extensions and spiroplasmas accumulated between the laminae rara and densa of the basal lamina. Tip structures of flask-shaped spiroplasmas pierced the lamina densa that was discontinuous in close proximity to spiroplasmas. Spiroplasmas were found in hemolymph, crossed the basal lamina of Malpighian tubule epithelium and accumulated at high numbers in muscle cells that had cytopathogenic changes. S. kunkelii had perithrochous approximately 8nm diameter structures determined to be fimbriae protruding from the cell surface, and similar structures were adhering to the basal lamina of midgut epithelium and to external lamina of muscle cells. Further, spiroplasmas had pili-like appendages at one or both cell poles and appeared to conjugate. This is the first time that fimbriae and pili have been observed in a mollicutes.


Asunto(s)
Hemípteros/microbiología , Insectos Vectores/ultraestructura , Túbulos de Malpighi/microbiología , Spiroplasma/patogenicidad , Spiroplasma/ultraestructura , Animales , Femenino , Inmunohistoquímica , Masculino , Túbulos de Malpighi/ultraestructura , Microscopía Electrónica , Músculo Liso/microbiología , Músculo Liso/ultraestructura , Infecciones por Mycoplasmatales/patología
14.
Pancreatology ; 2(5): 449-55, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12378112

RESUMEN

BACKGROUND: Infections are frequent complications and determine clinical course and outcome in severe pancreatitis. A novel animal model was used to assess minimal transit time of bacterial translocation (BT) across the gut mucosa in vivo using green fluorescent protein-transfected Escherichia coli and intravital video microscopy. METHODS: Three hours after induction of acute pancreatitis by i.p. injection of 40 microg/kg cerulein, 0.5 ml of a suspension of green fluorescent protein-transfected E. coli were injected into the lumen of a small bowel reservoir formed by ligature in anesthetized Wistar rats. Translocation of E. coli was assessed by intravital microscopy. Animals were sacrificed 5 h after induction of pancreatitis. RESULTS: BT across the mucosa and into the muscularis propria took a mean +/- SD of 36.4 +/- 8 min and 80.9 +/- 9.5 min, respectively, in sham animals. Pancreatitis resulted in a significantly shorter minimal transit time across the mucosa (16.4 +/- 4.9 min, p = 0.007) and into the muscularis propria (47.7 +/- 2.5 min, p = 0.001). E. coli were detected on frozen cross-sections and on bacteriological examination of pancreatic tissue in animals with acute pancreatitis but not in controls. DISCUSSION: Intravital microscopy of fluorescent bacteria is a new approach towards studying BT in vivo. Minimal transit time of BT serves as a novel functional aspect of mucosal barrier function during acute pancreatitis. The observation of fluorescent bacteria translocating from the small bowel lumen into the pancreas provides substantial experimental proof for the gut-origin-hypothesis of infectious complications in pancreatitis.


Asunto(s)
Escherichia coli/aislamiento & purificación , Íleon/microbiología , Mucosa Intestinal/microbiología , Pancreatitis/microbiología , Enfermedad Aguda , Animales , Ceruletida , Modelos Animales de Enfermedad , Masculino , Microscopía por Video , Músculo Liso/microbiología , Necrosis , Pancreatitis/inducido químicamente , Pancreatitis/patología , Ratas , Ratas Wistar
15.
J Clin Microbiol ; 40(5): 1783-90, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11980960

RESUMEN

The causative agent of Johne's disease is Mycobacterium avium subsp. paratuberculosis. This is a chronic, debilitating gastrointestinal disorder that affects ruminants and is responsible for significant economic loss. The specimen processing method that combines C(18)-carboxypropylbetaine (CB-18) treatment and lytic enzyme decontamination has been shown to improve the diagnosis of mycobacterioses. This processing method was applied to the isolation of M. avium subsp. paratuberculosis from ruminant tissue samples. The BACTEC 12B liquid culture system was used but was supplemented with 1% egg yolk emulsion, 4 microg of mycobactin J, and 0.5% pyruvate (12B/EMP) for use in conjunction with this method. The final concentration of antibiotics used was 10 microg of vancomycin, 30 microg of amphotericin B, and 20 microg of nalidixic acid (VAN) per ml. A 7H10-based solid medium was also used that included mycobactin J, pyruvate, and VAN but excluded the egg yolk emulsion (7H10/MPV). Several M. avium subsp. paratuberculosis isolates were examined during the evaluation of this processing method. It was observed that treatment with lytic enzymes stimulated the growth of M. avium subsp. paratuberculosis; however, the growth of one isolate was markedly inhibited due to the presence of vancomycin. Subsequently, the vancomycin concentration in the VAN formulation was reduced to 2 microg/ml. A blinded panel of 60 previously characterized tissue samples from bovine and bison were then processed and analyzed by smear and culture. Historically, 31 and 37 specimens were classified as positive by histology and culture, respectively. The overall sensitivity and specificity of smear relative to culture following CB-18 processing were 97.6 and 89.5%, respectively. The 12B/EMP/VAN liquid culture system recovered M. avium subsp. paratuberculosis from 39 specimens, whereas 7H10/MPV and Herrold's egg yolk media recovered M. avium subsp. paratuberculosis from 26 and 16 specimens, respectively. The average times to positive were 7.4 +/- 8.3, 29.9 +/- 2.6, and 24 +/- 0 days, respectively. The contamination rates were 4.8, 22.6, and 20.0%, respectively.


Asunto(s)
Betaína/análogos & derivados , Betaína/análisis , Infecciones por Mycobacterium/virología , Mycobacterium avium/aislamiento & purificación , Rumiantes/microbiología , Manejo de Especímenes/métodos , Tuberculosis/veterinaria , Animales , Técnicas Bacteriológicas , Bison/microbiología , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Íleon/microbiología , Indicadores y Reactivos , Cinética , Músculo Liso/microbiología , Infecciones por Mycobacterium/diagnóstico , Mycobacterium avium/crecimiento & desarrollo , Oxazoles/análisis , Reacción en Cadena de la Polimerasa/métodos , Factores de Tiempo , Tuberculosis/diagnóstico
16.
FEMS Immunol Med Microbiol ; 32(1): 9-15, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11750216

RESUMEN

Clinical studies have suggested a causal or contributory role of Chlamydia pneumoniae infection in asthma and atherosclerosis. The activation of synthetic functions of smooth muscle cells (SMC) including the production of cytokines and growth factors plays a major role in the formation of fibrous atherosclerotic plaques as well as in structural remodelling of the airway wall in chronic asthma. In this study we demonstrated that C. pneumoniae induced the production of low levels of interferon (IFN)-beta in bronchial and vascular SMC when infected cells were treated with tumour necrosis factor-alpha (TNF-alpha). IFN-beta production was analysed by reverse transcription-PCR and enzyme-linked immunosorbent assay. The upregulation of IFN-beta was paralleled by an increase in mRNA levels of interferon regulatory factor-1 and interferon-stimulated gene factor 3gamma, two transcription factors activating the expression of the IFN-beta gene. In addition, C. pneumoniae infection enhanced the mRNA level of indoleamine 2,3-dioxygenase, an IFN-inducible factor mediating the restriction of intracellular chlamydial growth, in TNF-alpha-stimulated SMC. C. pneumoniae-induced IFN-beta production by SMC may modulate inflammation and tissue remodelling during respiratory and vascular infection.


Asunto(s)
Infecciones por Chlamydia/microbiología , Chlamydophila pneumoniae/inmunología , Interferón beta/biosíntesis , Músculo Liso/microbiología , Bronquios/citología , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , Humanos , Factor 1 Regulador del Interferón , Factor 3 de Genes Estimulados por el Interferón , Subunidad gamma del Factor 3 de Genes Estimulados por el Interferón , Interferón beta/genética , Músculo Liso/inmunología , Músculo Liso Vascular/citología , Fosfoproteínas/metabolismo , Factores de Transcripción/metabolismo
17.
Infect Immun ; 68(6): 3635-41, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10816522

RESUMEN

Chlamydia pneumoniae infection has been associated with asthma and atherosclerosis. Smooth muscle cells represent host cells for chlamydiae during chronic infection. In this study we demonstrated that C. pneumoniae infection of human smooth muscle cells in vitro increased production of interleukin 6 (IL-6) and basic fibroblast growth factor (bFGF) as shown by reverse transcription-PCR, immunoblotting, and enzyme-linked immunosorbent assay. In contrast, levels of platelet-derived growth factor A-chain mRNA were not affected after infection. The stimulation of bFGF and IL-6 production was most effective when viable chlamydiae were used as inoculum. Furthermore, inhibition of bacterial protein synthesis with chloramphenicol prevented up-regulation of IL-6 and bFGF in infected cells. Addition of IL-6 antibody to infected cultures diminished bFGF expression, indicating involvement of produced IL-6. These findings suggest that chlamydial infection of smooth muscle cells elicits a cytokine response that may contribute to structural remodeling of the airway wall in chronic asthma and to fibrous plaque formation in atherosclerosis.


Asunto(s)
Chlamydophila pneumoniae/inmunología , Factor 2 de Crecimiento de Fibroblastos/biosíntesis , Interleucina-6/biosíntesis , Músculo Liso/microbiología , Arteriosclerosis/etiología , Asma/etiología , Bronquios/citología , Chlamydia trachomatis/inmunología , Inmunoensayo , Factor de Crecimiento Derivado de Plaquetas/biosíntesis , Especificidad de la Especie
18.
Infect Immun ; 65(2): 503-6, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9009304

RESUMEN

Recent observations have shown that both Chlamydia pneumoniae antigens and DNA may be found within atherosclerotic lesions. In this study, we evaluated the ability of C. pneumoniae to infect cells that make up atherosclerotic lesions, including endothelial cells, smooth muscle cells, and cholesterol-loaded smooth muscle cells. The organism readily infected rabbit, bovine, and human aortic smooth muscle cells. Cholesterol-loaded smooth muscle cells were even more susceptible to C. pneumoniae infection. Chlamydia trachomatis inefficiently infected smooth muscle cells, demonstrating that this is not a characteristic of all members of the genus Chlamydia. C. pneumoniae infected bovine endothelial cells poorly. This study demonstrates that C. pneumoniae readily infects one of the important types of cells found within atherosclerotic lesions, i.e., smooth muscle cells with and without cholesterol loading.


Asunto(s)
Chlamydophila pneumoniae/inmunología , Músculo Liso/citología , Músculo Liso/microbiología , Animales , Bovinos , Recuento de Células , Línea Celular , Infecciones por Chlamydia/microbiología , Infecciones por Chlamydia/patología , Chlamydia trachomatis/inmunología , Colesterol/farmacología , Humanos , Inmunidad Innata , Músculo Liso/efectos de los fármacos , Conejos
20.
Langenbecks Arch Chir ; 379(6): 361-7, 1994.
Artículo en Alemán | MEDLINE | ID: mdl-7845163

RESUMEN

In an experimental study an intestinal neosphincter (INS) was constructed by modifying the principle of the ileocolic nipple-valve anastomosis by means of ultrasonic tissue fragmentation of the contacting serosa of the ileum and the corresponding mucosa of the ileum and colon. The healing of the muscle layers was studied histologically. The function of the INS was investigated in six dogs and compared intraindividually with that of the ileocecal valve and conventional end-to-end anastomosis. Morphologically the neospincters healed within 3 months without major fibrosis. The reference values of the aerobic and anaerobic bacterial counts in the terminal ileum were more than 2 logs lower than in the colon with the normal ileocecal valve, and after ileo-colonic end-to-end-anastomosis bacterial colonization of the terminal ileum was found both qualitatively and quantitatively. Subsequent interposition of the INS led to bacterial clearance of the terminal ileum. The median aerobic bacterial counts were lower by six logs and the an aerobic bacterial counts by 3 logs than in the colon. However, differences were not statistically significant owing to the wide variation in the individual values. Nevertheless, the demonstrable clearance of the terminal ileum could be explained by the orthograde passage with absolutely no stagnation and the relative competence of the INS in resisting retrograde pressure competence. In conclusion, ultrasonic fragmentation of the serosa and mucosa of the bowel allows construction of an INS from three muscle layers, which acts as a bacteriological barrier. Before it is introduced into the clinical setting its integration into the intestinal motility should be evaluated by further studies.


Asunto(s)
Anastomosis Quirúrgica/métodos , División Celular/fisiología , Válvula Ileocecal/cirugía , Cicatrización de Heridas/fisiología , Animales , Recuento de Colonia Microbiana , Perros , Femenino , Tránsito Gastrointestinal/fisiología , Válvula Ileocecal/microbiología , Válvula Ileocecal/patología , Masculino , Músculo Liso/microbiología , Músculo Liso/patología , Músculo Liso/cirugía , Técnicas de Sutura
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