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1.
Eur J Cancer Prev ; 31(4): 377-384, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34545023

RESUMO

BACKGROUND: The incidence of cutaneous melanoma has risen faster than almost any other type of cancer in the last 50 years. Ultraviolet (UV) radiation and genetic susceptibility are the most important risk factors. OBJECTIVE: We aimed to determine the epidemiologic indicators of melanoma in Hungary, a country with an estimated population of 9.8 million and an area of 93 030 km2. METHODS: Anonymized patient records from the National Health Insurance Fund Management covering the entire population were used to determine the incidence and prevalence of melanoma in the counties of Hungary from 2013 to 2017. Altogether 20 030 melanoma cases were identified for inclusion in this study. RESULTS: The prevalence of melanoma increased over the investigated period and was significantly higher among women than men. The incidence of melanoma stagnated during this period and the incidence rate was the highest among the elderly. Interestingly, the incidence was higher in males in the elderly population, while the incidence was higher in females in the younger (<60 years) population. Geographical variations in ambient UV radiation did not show statistically significant correlation with the regional variability of epidemiologic indicators, probably due to small differences in the number of bright sunshine hours per year between regions. Although Hungary is a relatively small country, we observed regional heterogeneity in socioeconomic factors. Notably, a significant and strong negative correlation was found between single-person household rates and melanoma prevalence. CONCLUSION: In addition to ambient UV radiation, melanoma incidence and prevalence appear to be related to age, gender and socioeconomic factors.


Assuntos
Melanoma , Neoplasias Cutâneas , Idoso , Feminino , Humanos , Hungria/epidemiologia , Incidência , Masculino , Melanoma/epidemiologia , Melanoma/etiologia , Melanoma/prevenção & controle , Prevalência , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/prevenção & controle , Fatores Socioeconômicos , Raios Ultravioleta/efeitos adversos
3.
J Gastrointestin Liver Dis ; 26(4): 395-402, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29253055

RESUMO

BACKGROUND AND AIMS: Aspirin is one of the most widely used medication for its analgesic and anti-platelet properties and thus a major cause for gastrointestinal (GI) bleeding. This study compared the preventive effect of histamine-2 receptor antagonists (H2RAs) and proton-pump inhibitors (PPIs) against chronic low-dose aspirin (LDA)-related GI bleeding and ulcer formation. METHODS: Electronic databases of Pubmed, Embase and Cochrane Central Register of Controlled Trials were searched for human observations (randomised controlled trials and observational studies) comparing the long term effects of PPIs and H2RAs treatment in the prevention of GI bleeding or ulcer formation in patients on chronic LDA treatment listed up till September 30, 2016. Two independent authors searched databases using PICO questions (aspirin, H2RA, PPI, GI bleeding or ulcer), and reviewed abstracts and articles for comprehensive studies keeping adequate study quality. Data of weighted odds ratios were statistically evaluated using Comprehensive Metaanalysis (Biostat, Inc., Engelwood, MJ, USA), potential bias was checked. RESULTS: Nine studies for GI bleeding and eight studies for ulcer formation were found meeting inclusion criteria, altogether 1,879 patients were included into review. The H2RAs prevented less effectively LDA-related GI bleeding (OR= 2.102, 95% CI: 1.008-4.385, p<0.048) and ulcer formation (OR= 2.257, 95% CI: 1.277-3.989, p<0.005) than PPIs. CONCLUSION: The meta-analysis showed that H2RAs were less effective in the prevention of LDA-related GI bleeding and ulcer formation suggesting the preferable usage of PPIs in case of tolerance.


Assuntos
Aspirina/efeitos adversos , Hemorragia Gastrointestinal/prevenção & controle , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Bomba de Prótons/uso terapêutico , Aspirina/administração & dosagem , Esquema de Medicação , Hemorragia Gastrointestinal/induzido quimicamente , Humanos , Úlcera Péptica/induzido quimicamente , Úlcera Péptica/prevenção & controle
4.
Curr Neuropharmacol ; 14(8): 901-913, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27440445

RESUMO

BACKGROUND: The authors, as internists, registered significant difference in the long lasting actions of surgical and chemical (atropine treatment) vagotomy in patients with peptic ulcer during second half of the last century (efficency, gastric acid secretion, gastrointestinal side effects, briefly benefical and harmful actions were examined). AIMS: 1. Since the authors participated in the establishing of human clinical pharmacology in this field, they wanted to know more and more facts of the acute and chronic effects of surgical and chemical (atropine treatment) on the gastrointestinal mucosal biochemisms and their actions altered by bioactive compounds and scavengers regarding the development of gastric mucosal damage and protection. METHODS: The observations were carried out in animals under various experimental conditions (in intact, pylorus-ligated rats, in different experimental ulcer models, together with application of various mucosal protecting compounds) without and with surgical vagotomy and chemical vagotomy produced by atropine treatment. RESULTS: 1. No changes were obtained in the cellular energy systems (ATP, ADP, AMP, cAMP, "adenylate pool", "energy charge" [(ATP+0.5 ADP)/ (ATP+ADP+AMP)] of stomach (glandular part, forestomach) in pylorus ligated rats after surgical vagotomy in contrast to those produced by only chemical vagotomy; 2. The effects of the gastric mucosal protective compounds [atropine, cimetidine, prostaglandins, scavengers (like vitamin A, ß-carotene), capsaicin] disappeared after surgical vagotomy; 3. The extents of different chemical agents induced mucosal damaging effects were enhanced by surgical vagotomy and was not altered by chemical vagotomy; 4. The existence of feedback mechanisms of pharmacological (cellular and intracellular) regulatory mechanisms between the membrane-bound ATPdependent energy systems exists in the gastric mucosa of intact animals, and after chemical vagotomy, but not after surgical vagotomy. CONCLUSIONS: 1. Increased vagal nerve activity takes place in the gastric mucosal damage; 2 both surgical and chemical vagotomy result mucosal protective affect on the gastric mucosal in different damaging experimental models; 3. The capsaicin-induced gastric mucosal damage depends on the applied doses, presence of anatomically intact vagal nerve (but independent from the chemical vagotomy), 4. The central and pheripheral neural regulations differ during gastric mucosal damage and protection induced by drugs, bioactive compounds, scavengers.


Assuntos
Encéfalo/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Intestinal/metabolismo , Nervo Vago/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Mucosa Gástrica/efeitos dos fármacos , Humanos , Mucosa Intestinal/efeitos dos fármacos , Nervo Vago/efeitos dos fármacos , Nervo Vago/cirurgia
5.
World J Gastrointest Pharmacol Ther ; 2(5): 36-41, 2011 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-22046579

RESUMO

AIM: To study the role of capsaicin-sensitive afferent nerves in Helicobacter pylori (H. pylori) positive chronic gastritis before and after eradication. METHODS: Gastric biopsy samples were obtained from corpus and antrum mucosa of 20 healthy human subjects and 18 patients with H. pylori positive chronic gastritis (n = 18) before and after eradication. Traditional gastric mucosal histology (and Warthin-Starry silver impregnation) and special histochemical examinations were carried out. Immunohistochemistry for capsaicin receptor (TRVP1), calcitonin gene-related peptide (CGRP) and substance P (SP) were carried out by the labeled polymer immunohistological method (Lab Vision Co., USA) using polyclonal rabbit and rat monoclonal antibodies (Abcam Ltd., UK). RESULTS: Eradication treatment was successful in 16 patients (89%). Seven patients (7/18, 39%) remained with moderate complaints, meanwhile 11 patients (11/28, 61%) had no complaints. At histological evaluation, normal gastric mucosa was detected in 4 patients after eradication treatment (4/18, 22%), and moderate chronic gastritis could be seen in 14 (14/18, 78%) patients. Positive immuno-staining for capsaicin receptor was seen in 35% (7/20) of controls, 89% (16/18, P < 0.001) in patients before and 72% (13/18, P < 0.03) after eradication. CGRP was positive in 40% (8/20) of controls, and in 100% (18/18, P < 0.001) of patients before and in 100% (18/18, P < 0.001) after eradication. The immune-staining of gastric mucosa for substance-P was positive in 25% (5/20) of healthy controls, and in 5.5% (3/18, P > 0.05) of patients before and in 0% of patients (0/18, P > 0.05) after H. pylori eradication. CONCLUSION: Distibution of TRVP1 and CGRP is altered during the development of H. pylori positive chronic gastritis. The immune-staining for TRVP1, CGRP and SP rwemained unchanged before and after H. pylori eradication treatment. The capsaicin-sensitive afferentation is an independent from the eradication treatment. The 6 wk time period might not be enough time for the restituion of chronic H. pylori positive chronic gastritis. The H. pylori infection might not represent the main pathological factor in the development of chronic gastritis.

6.
Curr Pharm Des ; 17(16): 1556-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21548870

RESUMO

Our clinical observations proved that the the duodenal ulcer in patients healed without any inhibition of gastric acid secretion (1965), and the healing rates of atropine vs cimetidine vs Carbenoxolone were equal and superior to that of placebo in randomized, prospective and multiclinical study of DU patients (1978). The phenomenon of gastric cytoprotection was defined by André Robert in rats (1979). The essential point of this phenomenon is that the prostaglandins prevent the chemical-induced gastric mucosal damage without affecting gastric acid secretion, this being originally suggested as a reaction specific to prostaglandins. Since then gastrointestinal cytoprotection has been shown with various agents (anticholinergic agents, H(2)RA, growth factors, body protecting compound, BPC) and retinoids in animals; the latter differing from the actions of vitamin A. In examining the various components of gastrointestinal cytoprotection , different studies have performed in isolated cells, stable cell lines, animal experiments, healthy human subjects, in patients chronic gastric and duodenal ulcers, and with different gastrointestinal disorders. Our attention has focused on the effects of cytoprotective agents on cellular viability, mitochondrial and DNA damage, oxygen free radicals, natural antioxidant systems, mucosal biochemistry, vascular events, gastrointestinal mucosal protection as well as in their prevention of different human diseases. This paper gives an overview on the different approaches for the exploring gastrointestinal cytoprotection (at the level of isolated cells, animal experiments, healthy human beings and patients with different gastrointestinal disorders). It has been indicated that the gastric cytoprotection exists in animals, human healthy subjects, patients with different gastrointestinal disorders. The our human observation in patients with duodenal ulcer healed without any changes of gastric acid secretion, there were no significant differences between the cimetidine vs. atropine (as antisecterory agents) or vs. Carbenoxolone vs. retinoid (as cytoprotective compounds) treatment. Also we indicated the presence of intact vagal nerve basically necessary for development of gastrointestinal cytoprotection and for capsaicin-sensitive vagal nerve induced mucosal protection (1982).


Assuntos
Citoproteção , Gastroenteropatias/prevenção & controle , Animais , Feminino , Gastroenteropatias/patologia , Humanos , Masculino , Ratos
7.
Eur J Ophthalmol ; 18(5): 703-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18850546

RESUMO

PURPOSE: The purpose of the study was to examine the corneal inflammatory reaction and Langerhans cells with confocal microscopy after metal foreign body removal. METHODS: Corneal metal foreign body was removed from 9 eyes of 9 consecutive patients 12.1+/-13.6 (4 to 72) hours after superficial angle grinder injury. Both eyes were examined with the Heidelberg Retina Tomograph II (HRT II) Rostock Cornea Module. Morphology and density of epithelium, nerves, metal deposits, keratocytes, endothelium, and Langerhans cells were compared to the uninjured fellow eyes (controls). RESULTS: Irregularity and partially missing superficial epithelium was found in all cases. Around the area of injury prolonged basal and wing epithelial cells were found in all eyes. The basal epithelium density is lower than in the control eye (p=0.043). Density of Langerhans cells (68.1+/-24.2/mm2) was increased in the epithelium, compared to controls (35.2+/-21.8/mm2, p=0.012). Keratocyte and endothelium densities were not different from that of controls. Some keratocytes showed signs of activation and the inhomogeneous background reflectivity revealed extracellular matrix alterations. Inflammatory reaction was observed up to260 micronm depth. The metal foreign body particles had high reflectivity and irregular edge. CONCLUSIONS: In vivo confocal microscopy provided additional information to biomicroscopic signs such as epithelial damage and inflammation. It showed the effects of metal foreign bodies in the cornea: nerve damage and Langerhans cell density increase. Langerhans cells seem to play an important role in the inflammatory response after corneal foreign body injuries.


Assuntos
Córnea/imunologia , Lesões da Córnea , Corpos Estranhos no Olho/imunologia , Ferimentos Oculares Penetrantes/imunologia , Células de Langerhans/imunologia , Metais , Adulto , Contagem de Células , Epitélio Corneano/patologia , Corpos Estranhos no Olho/cirurgia , Ferimentos Oculares Penetrantes/cirurgia , Humanos , Células de Langerhans/patologia , Microscopia Confocal , Procedimentos Cirúrgicos Oftalmológicos
8.
Ophthalmologe ; 104(8): 697-700, 702-4, 2007 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-17593371

RESUMO

BACKGROUND: To investigate the particles of commercially used ophthalmic suspensions with the HRT II Rostock Cornea Module and to compare them with particle parameters given in the literature. METHODS: Software-aided analysis was carried out for the suspensions brinzolamide 1%, betaxolol HCl 0.25%, dexamethasone phosphate 0.1% and prednisolone acetate 0.5%, including measurements of length, area and circumference and calculation of ellipticity and shape factor (SF). RESULTS: Particle characteristics (SF and ellipticity) of different suspensions demonstrated that the particles are not spherical. Significant aggregation affinity of prednisolone acetate particles was observed. CONCLUSION: Exact and reproducible in vitro microstructural examination of ophthalmic suspensions was possible due to the high resolution of the HRT II Rostock Cornea Module.


Assuntos
Betaxolol/química , Dexametasona/química , Microscopia Confocal/instrumentação , Soluções Oftálmicas/química , Tamanho da Partícula , Prednisolona/química , Sulfonamidas/química , Tiazinas/química , Química Farmacêutica , Coloides/química , Microscopia Confocal/métodos , Suspensões
9.
Ophthalmologe ; 102(2): 140-6, 2005 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-15378334

RESUMO

BACKGROUND: Seven eyes with clear grafts after penetrating keratoplasty were examined with in vivo confocal corneal microscopy in 1999. Our aim was the confocal microscopic investigation of the subclinical changes in clear grafts after long-term follow-up. METHODS: The preoperative diagnoses were keratoconus (two), granular corneal dystrophy (two), pseudophakic bullous keratopathy due to ACL (two), and corneal ulcer (one). The epithelium, corneal nerves, keratocytes of the anterior and posterior stroma, and endothelium were evaluated with confocal microscopy. RESULTS: Mean density of basal epithelial cells was 3928+/-378 cells/mm(2) at 15 months and 3284+/-565 cells/mm(2) at 66 months postoperatively. At 15 months the keratocyte density was 750+/-113 cells/mm(2) in the anterior stroma and 601+/-98 cells/mm(2) in the posterior stroma, at 66 months 383+/-53 cells/mm(2) in the anterior stroma and 411+/-98 cells/mm(2) in the posterior stroma. Endothelial cell density decreased from 1719+/-576 cells/mm(2) (15 months) to 965+/-272 cells/mm(2) (66 months). CONCLUSIONS: In the follow-up period a significant decrease of keratocyte and endothelial cell density was detectable with confocal microscopy. The clinical importance of our findings must be clarified with further examinations on more patients.


Assuntos
Córnea/cirurgia , Doenças da Córnea/patologia , Doenças da Córnea/cirurgia , Transplante de Córnea/métodos , Sobrevivência de Enxerto , Microscopia Confocal/métodos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Transplantes , Resultado do Tratamento
10.
Exp Biol Med (Maywood) ; 227(6): 412-24, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12037131

RESUMO

Repair of superficial gastric mucosal injury is accomplished by the process of restitution-migration of epithelial cells to restore continuity of the mucosal surface. Actin filaments, focal adhesions, and focal adhesion kinase (FAK) play crucial roles in cell motility essential for restitution. We studied whether epidermal growth factor (EGF) and/or indomethacin (IND) affect cell migration, actin stress fiber formation, and/or phosphorylation of FAK and tensin in wounded gastric monolayers. Human gastric epithelial monolayers (MKN 28 cells) were wounded and treated with either vehicle or 0.5 mM IND for 16 hr followed by EGF. EGF treatment significantly stimulated cell migration and actin stress fiber formation, and increased FAK localization to focal adhesions, and phosphorylation of FAK and tensin, whereas IND inhibited all these at the baseline and EGF-stimulated conditions. IND-induced inhibition of FAK phosphorylation preceded changes in actin polymerization, indicating that actin depolymerization might be the consequence of decreased FAK activity. In in vivo experiments, rats received either vehicle or IND (5 mg/kg i.g.), and 3 min later, they received water or 5% hypertonic NaCl; gastric mucosa was obtained at 1, 4, and 8 hr after injury. Four and 8 hr after hypertonic injury, FAK phosphorylation was induced in gastric mucosa compared with controls. IND pretreatment significantly delayed epithelial restitution in vivo, and reduced FAK phosphorylation and recruitment to adhesion points, as well as actin stress fiber formation in migrating surface epithelial cells. Our study indicates that FAK, tensin, and actin stress fibers are likely mediators of EGF-stimulated cell migration in wounded human gastric monolayers and potential targets for IND-induced inhibition of restitution.


Assuntos
Actinas/metabolismo , Indometacina/farmacologia , Proteínas dos Microfilamentos/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Estômago/efeitos dos fármacos , Fibras de Estresse/metabolismo , Animais , Apoptose , Caspase 3 , Caspases/metabolismo , Morte Celular , Linhagem Celular , Movimento Celular , Inibidores de Ciclo-Oxigenase/farmacologia , Relação Dose-Resposta a Droga , Fator de Crescimento Epidérmico/metabolismo , Células Epiteliais/metabolismo , Quinase 1 de Adesão Focal , Proteína-Tirosina Quinases de Adesão Focal , Mucosa Gástrica/metabolismo , Humanos , Immunoblotting , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Mitomicina/farmacologia , Necrose , Fosforilação , Testes de Precipitina , Ratos , Ratos Sprague-Dawley , Tensinas , Fatores de Tempo , Tirosina/metabolismo
11.
Am J Gastroenterol ; 97(3): 542-53, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11922545

RESUMO

Epidemiological studies suggest that aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) reduce the incidence of and mortality from colorectal, gastric, and esophageal cancers. The precise mechanisms by which NSAIDs exert their chemopreventive effects are not fully explained, but likely involve inhibition of cyclo-oxygenase, the enzyme that converts arachidonic acid to prostaglandins. Two isoforms of this enzyme, cyclo-oxygenase 1 (COX-1) and COX-2, have been identified. COX-2 is absent in normal mucosa but is overexpressed in colonic, gastric, and esophageal cancers, as well as their precursor lesions. The inhibition of COX-2 through either pharmacological agents or gene deletion results in suppression of colonic polyp formation. NSAIDs reduce colonic, gastric, and esophageal cancer cell growth, in part, by inducing apoptosis. However, the antineoplastic effects of NSAIDs may be partly independent of their ability to inhibit COX-2. The mechanisms involved in the antineoplastic actions of NSAIDs include inhibition of angiogenesis (essential for delivery of oxygen and nutrients to a growing tumor), induction of apoptosis (which is usually reduced in cancer cells) by stimulation of proapoptotic genes, and direct inhibition of cancer cell growth by blocking signal transduction pathways responsible for cell proliferation.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticarcinógenos/farmacologia , Anticarcinógenos/uso terapêutico , Quimioprevenção , Neoplasias Gastrointestinais/prevenção & controle , Neoplasias Gastrointestinais/fisiopatologia , Animais , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/fisiopatologia , Humanos , Técnicas In Vitro , Camundongos
12.
Nat Med ; 8(3): 289-93, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11875501

RESUMO

Prostaglandins (PGs), bioactive lipid molecules produced by cyclooxygenase enzymes (COX-1 and COX-2), have diverse biological activities, including growth-promoting actions on gastrointestinal mucosa. They are also implicated in the growth of colonic polyps and cancers. However, the precise mechanisms of these trophic actions of PGs remain unclear. As activation of the epidermal growth factor receptor (EGFR) triggers mitogenic signaling in gastrointestinal mucosa, and its expression is also upregulated in colonic cancers and most neoplasms, we investigated whether PGs transactivate EGFR. Here we provide evidence that prostaglandin E2 (PGE2) rapidly phosphorylates EGFR and triggers the extracellular signal-regulated kinase 2 (ERK2)--mitogenic signaling pathway in normal gastric epithelial (RGM1) and colon cancer (Caco-2, LoVo and HT-29) cell lines. Inactivation of EGFR kinase with selective inhibitors significantly reduces PGE2-induced ERK2 activation, c-fos mRNA expression and cell proliferation. Inhibition of matrix metalloproteinases (MMPs), transforming growth factor-alpha (TGF-alpha) or c-Src blocked PGE2-mediated EGFR transactivation and downstream signaling indicating that PGE2-induced EGFR transactivation involves signaling transduced via TGF-alpha, an EGFR ligand, likely released by c-Src-activated MMP(s). Our findings that PGE2 transactivates EGFR reveal a previously unknown mechanism by which PGE2 mediates trophic actions resulting in gastric and intestinal hypertrophy as well as growth of colonic polyps and cancers.


Assuntos
Neoplasias do Colo/metabolismo , Dinoprostona/metabolismo , Receptores ErbB/metabolismo , Mucosa Gástrica/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Ativação Transcricional/fisiologia , Animais , Linhagem Celular , Dinoprostona/farmacologia , Inibidores Enzimáticos/farmacologia , Mucosa Gástrica/citologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Genes src/fisiologia , Humanos , Hipertrofia/patologia , Metaloproteinases da Matriz/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Fosforilação , Quinazolinas/farmacologia , Ratos , Ratos Sprague-Dawley , Tirfostinas/farmacologia
13.
Am J Pathol ; 160(3): 963-72, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11891194

RESUMO

Nonsteroidal anti-inflammatory drugs, both nonselective and cyclooxygenase-2 (COX-2) selective, delay gastric ulcer healing. Whether they affect esophageal ulcer healing remains unexplored. We studied the effects of the COX-2 selective inhibitor, celecoxib, on esophageal ulcer healing as well as on the cellular and molecular events involved in the healing process. Esophageal ulcers were induced in rats by focal application of acetic acid. Rats with esophageal ulcers were treated intragastrically with either celecoxib (10 mg/kg, once daily) or vehicle for 2 or 4 days. Esophageal ulceration triggered increases in: esophageal epithelial cell proliferation; expression of COX-2 (but not COX-1); hepatocyte growth factor (HGF) and its receptor, c-Met; and activation of extracellular signal-regulated kinase 2 (ERK2). Treatment with celecoxib significantly delayed esophageal ulcer healing and suppressed ulceration-triggered increases in esophageal epithelial cell proliferation, c-Met mRNA and protein expression, and ERK2 activity. In an ex vivo organ-culture system, exogenous HGF significantly increased ERK2 phosphorylation levels in esophageal mucosa. A structural analog of celecoxib, SC-236, completely prevented this effect. These findings indicate that celecoxib delays esophageal ulcer healing by reducing ulceration-induced esophageal epithelial cell proliferation. These actions are associated with, and likely mediated by, down-regulation of the HGF/c-Met-ERK2 signaling pathway.


Assuntos
Inibidores de Ciclo-Oxigenase/farmacologia , Doenças do Esôfago/metabolismo , Esôfago/metabolismo , Esôfago/patologia , Isoenzimas/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismo , Sulfonamidas/farmacologia , Úlcera/metabolismo , Animais , Celecoxib , Ciclo-Oxigenase 2 , Inibidores de Ciclo-Oxigenase 2 , Regulação para Baixo/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Doenças do Esôfago/patologia , Esôfago/efeitos dos fármacos , Masculino , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Prostaglandina-Endoperóxido Sintases , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Pirazóis , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Úlcera/patologia , Cicatrização/efeitos dos fármacos
14.
Gastroenterology ; 122(2): 458-68, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11832460

RESUMO

BACKGROUND & AIMS: Cellular and molecular mechanisms of esophageal ulcer healing remain unexplored. We studied the sequential cellular events and the expression of keratinocyte growth factor (KGF) and its receptor (KGF-R) during the healing of experimental esophageal ulcers. METHODS: Esophageal ulcers were produced in rats by local application of acetic acid. Studies included (1) ulcer size, (2) quantitative histology, and (3) KGF and KGF-R messenger RNA and protein expression by reverse-transcription polymerase chain reaction, Western blotting, and immunostaining. In separate groups, ulcer size and esophageal epithelial proliferation were evaluated after a single injection of recombinant human KGF (1 mg/kg) around the ulcer. RESULTS: Ulcers were fully developed 3 days after induction, and 58% of ulcers were re-epithelialized by 9 days. At 3 days, in esophageal tissue bordering the ulcers, KGF messenger RNA and protein were increased by 191% and 151%, respectively, and KGF-R messenger RNA and protein were increased by 357% and 237%, respectively. KGF was expressed in stromal cells, whereas KGF-R was expressed in epithelial cells. At 6 days, epithelial proliferation at the ulcer margin was increased by 216%, and treatment with KGF further enhanced cell proliferation and accelerated ulcer healing. CONCLUSIONS: KGF is a likely mediator of esophageal epithelial proliferation and ulcer healing.


Assuntos
Doenças do Esôfago/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Úlcera/metabolismo , Cicatrização/fisiologia , Animais , Western Blotting , Divisão Celular/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Doenças do Esôfago/tratamento farmacológico , Doenças do Esôfago/patologia , Fator 7 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos/farmacologia , Imunofluorescência , Expressão Gênica/fisiologia , Masculino , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Receptores de Fatores de Crescimento de Fibroblastos/análise , Receptores de Fatores de Crescimento de Fibroblastos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Úlcera/tratamento farmacológico , Úlcera/patologia , Cicatrização/efeitos dos fármacos
15.
Hepatology ; 35(2): 393-402, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11826414

RESUMO

Activation of endothelial nitric oxide synthase (eNOS) in portal hypertensive (PHT) gastric mucosa leads to hyperdynamic circulation and increased susceptibility to injury. However, the signaling mechanisms for eNOS activation in PHT gastric mucosa and the role of TNF-alpha in this signaling remain unknown. In PHT gastric mucosa we studied (1) eNOS phosphorylation (at serine 1177) required for its activation; (2) association of the phosphatidylinositol 3-kinase (PI 3-kinase), and its downstream effector Akt, with eNOS; and, (3) whether TNF-alpha neutralization affects eNOS phosphorylation and PI 3-kinase-Akt activation. To determine human relevance, we used human microvascular endothelial cells to examine directly whether TNF-alpha stimulates eNOS phosphorylation via PI 3-kinase. PHT gastric mucosa has significantly increased (1) eNOS phosphorylation at serine 1177 by 90% (P <.01); (2) membrane translocation (P <.05) and phosphorylation (P <.05) of p85 (regulatory subunit of PI 3-kinase) by 61% and 85%, respectively; (3) phosphorylation (P <.01) and activity (P <.01) of Akt by 40% and 52%, respectively; and (4) binding of Akt to eNOS by as much as 410% (P <.001). Neutralizing anti-TNF-alpha antibody significantly reduced p85 phosphorylation, phosphorylation and activity of Akt, and eNOS phosphorylation in PHT gastric mucosa to normal levels. Furthermore, TNF-alpha stimulated eNOS phosphorylation in human microvascular endothelial cells. In conclusion, these findings show that in PHT gastric mucosa, TNF-alpha stimulates eNOS phosphorylation at serine 1177 (required for its activation) via the PI 3-kinase-Akt signal transduction pathway.


Assuntos
Mucosa Gástrica/enzimologia , Hipertensão Portal/enzimologia , Óxido Nítrico Sintase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Células Cultivadas , Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Ativação Enzimática/fisiologia , Humanos , Hipertensão Portal/fisiopatologia , Microcirculação , Óxido Nítrico Sintase Tipo III , Fosforilação/efeitos dos fármacos , Veia Porta/fisiopatologia , Proteínas Proto-Oncogênicas c-akt , Ratos , Ratos Sprague-Dawley , Valores de Referência , Fator de Necrose Tumoral alfa/farmacologia , Pressão Venosa
16.
FASEB J ; 16(2): 264-6, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11772947

RESUMO

Nonsteroidal anti-inflammatory drugs (NSAIDs) block prostaglandin synthesis and impair healing of gastrointestinal ulcers and growth of colonic tumors, in part, by inhibiting angiogenesis. The mechanisms of this inhibition are incompletely explained. Here we demonstrate that both nonselective (indomethacin) and COX-2-selective (NS-398) NSAIDs inhibit hypoxia-induced in vitro angiogenesis in gastric microvascular endothelial cells via coordinated sequential events: 1) increased expression of the von Hippel-Lindau (VHL) tumor suppressor, which targets proteins for ubiquitination leading to 2) reduced accumulation of hypoxia-inducible factor-1alpha (HIF-1alpha) and, as a result, 3) reduced expression of vascular endothelial growth factor (VEGF) and its specific receptor Flt-1. Because HIF-1alpha is the major trigger for hypoxia-induced activation of the VEGF and Flt-1 genes, this could explain how NSAIDs inhibit hypoxia-induced angiogenesis. Exogenous VEGF and, to a lesser extent, exogenous prostaglandins partly reversed the NSAIDs inhibition of hypoxia-induced angiogenesis. Taken together, these results indicate that NSAIDs inhibit hypoxia-induced angiogenesis in endothelial cells by inhibiting VEGF and Flt-1 expression through increased VHL expression and the resulting ubiquitination and degradation of HIF-1alpha. This action of NSAIDs has both prostaglandin-dependent and prostaglandin-independent components.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Ligases/efeitos dos fármacos , Fatores de Transcrição/efeitos dos fármacos , Proteínas Supressoras de Tumor , Ubiquitina-Proteína Ligases , Animais , Hipóxia Celular/fisiologia , Linhagem Celular , Fatores de Crescimento Endotelial/genética , Fatores de Crescimento Endotelial/metabolismo , Fatores de Crescimento Endotelial/farmacologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Indometacina/farmacologia , Ligases/genética , Ligases/metabolismo , Linfocinas/efeitos dos fármacos , Linfocinas/genética , Linfocinas/metabolismo , Linfocinas/farmacologia , Neovascularização Patológica/fisiopatologia , Neovascularização Patológica/prevenção & controle , Nitrobenzenos/farmacologia , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Proteína Tirosina Quinases/efeitos dos fármacos , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Sulfonamidas/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ubiquitina/metabolismo , Fator A de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , Proteína Supressora de Tumor Von Hippel-Lindau
17.
Graefes Arch Clin Exp Ophthalmol ; 239(5): 356-60, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11482339

RESUMO

BACKGROUND: The aim of our study was to evaluate the reliability and reproducibility of in vivo slit-scanning corneal microscopy by endothelial analysis. METHODS: We examined 12 normal eyes of 12 persons. We analysed intraobserver differences in group I and interobserver differences in group II by manual and automatic evaluation of endothelial images. We also compared the methods of analysis in the two groups. We observed endothelial density, mean cell area, coefficient of variation and number of cells within the frame. RESULTS: In group I we found no significant difference between the observed parameters either by automatic or manual analysis. In group II no significant difference between the two observers was found using automatic analysis. On manual analysis, however, we observed a significant difference between endothelial density and the number of evaluated cells (P=0.0034 and P=0.0028). We observed a significant difference (P<0.001) between automatic and manual analysis concerning each parameter, with a rather tight linear correlation (Pearson correlation between 0.76 and 0.94). CONCLUSION: Automatic endothelial analysis was reliable and well reproducible in both--intraobserver and interobserver--groups. By manual evaluation, the clinical significance of interobserver differences can be disregarded. The differences between automatic and manual methods of analysis can be traced back to measurement technical reasons. We observed tight linear correlation between parameters. The data can be described well by linear regression. In vivo slit-scanning corneal microscopy may be an alternative to specular microscopic analyses for clinical use.


Assuntos
Endotélio Corneano/citologia , Microscopia Confocal/normas , Adolescente , Adulto , Idoso , Contagem de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes
20.
Orv Hetil ; 135(43): 2371-2, 1994 Oct 23.
Artigo em Húngaro | MEDLINE | ID: mdl-7970655

RESUMO

Bread produced with selenium-enriched yeast was given to ten volunteers. The daily dose contained approximately 100 micrograms of selenium. The subjects' mean baseline whole blood selenium concentration (52.2 +/- 16.7 micrograms/l) was indicative of a suboptimal selenium status. After two weeks of supplementation, the subjects' mean whole blood selenium level increased significantly (to 66.1 +/- 11.9 micrograms/l). Supplementation of selenium-enriched bread seems to be an easily implementable and promptly acting method of selenium status improvement.


Assuntos
Pão , Alimentos Fortificados , Selênio/administração & dosagem , Selênio/sangue , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência
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