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1.
J Pharm Biomed Anal ; 217: 114829, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35636006

RESUMO

IOA-289 is a novel small molecule inhibitor of autotaxin developed as a first-in-class therapy of fibrotic pathologies including cancer. A method for quantitation of IOA-289 in human plasma was developed using a stable isotope labeled compound ([13C4]IOA-289) as internal standard. The analytes were extracted from human plasma by protein precipitation and the analysis was performed by liquid chromatography coupled with tandem mass spectrometric detection (LCMS/MS). The chromatographic separation was performed with a gradient elution from a BEH C18 column and under these conditions the retention time and the run time were 1 and 2 min, respectively. The assay was fully validated over the range 3-3000 ng/mL, proved to be accurate, precise and selective and was successfully applied to quantitate IOA-289 in plasma samples from subjects in a first-in-humanclinical trial.


Assuntos
Plasma , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
2.
J Exp Med ; 184(3): 863-71, 1996 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9064346

RESUMO

A unique experimental model has been developed for dissecting the integrity of CD8+ T cell-mediated immunity to a persistent gammaherpesvirus under conditions of CD4+ T cell deficiency. Respiratory challenge of major histocompatibility complex class II -/- and +/+ C57BL/6J mice with the murine gammaherpesvirus 68 (MHV-68) leads to productive infection of both lung and adrenal epithelial cells. Virus titers peak within 5-10 d, and are no longer detected after day 15. Persistent, latent infection is established concurrently in splenic and lymph node B cells, with higher numbers of MHV-68+ lymphocytes being found in all lymphoid sites analyzed from the +/+ mice concurrent with the massive, but transient splenomegaly that occurred only in this group. From day 17, however, the numbers of infected B lymphocytes were consistently higher in the -/- group, while the frequency of this population diminished progressively in the +/+ controls. Infectious MHV-68 was again detected in the respiratory tract and the adrenals of the -/- (but not the +/+) mice from day 22 after infection. The titers in these sites rose progressively, with the majority of the -/- mice dying between days 120 and 133. Even so, some CD8+ effectors were still functioning as late as 100 d after infection. Depletion of CD8+ T cells at this stage led to higher virus titers in the -/- lung, and to the development of wasting in some of the -/- mice. Elimination of the CD8+ T cells from the +/+ group (day 80) increased the numbers of MHV-68+ cells in the spleen, but did not reactivate the infection in the respiratory tract. The results are consistent with the interpretation that CD8+ T cell-mediated control of this persistent gammaherpesvirus is progressively lost in the absence of the CD4+ T cell subset. This parallels what may be happening in AIDS patients who develop Kaposi's sarcoma and various Epstein Barr virus associated disease processes.


Assuntos
Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos/imunologia , Herpesvirus Humano 4 , Mononucleose Infecciosa/imunologia , Animais , Formação de Anticorpos , Ensaio de Imunoadsorção Enzimática , Antígenos H-2/imunologia , Herpesvirus Humano 4/crescimento & desenvolvimento , Interferon gama/metabolismo , Interleucina-6/metabolismo , Cinética , Camundongos , Camundongos Endogâmicos C57BL , Ativação Viral
3.
J Exp Med ; 185(9): 1641-50, 1997 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-9151901

RESUMO

The murine gamma-herpesvirus 68 has many similarities to EBV, and induces a syndrome comparable to infectious mononucleosis (IM). The frequency of activated CD8+ T cells (CD62L(lo)) in the peripheral blood increased greater than fourfold by 21 d after infection of C57BL/6J (H-2(b)) mice, and remained high for at least a further month. The spectrum of T cell receptor usage was greatly skewed, with as many as 75% of the CD8+ T cells in the blood expressing a Vbeta4+ phenotype. Interestingly, the Vbeta4 dominance was also seen, to varying extents, in H-2(k), H-2(d), H-2(u), and H-2(q) strains of mice. In addition, although CD4 depletion from day 11 had no effect on the Vbeta4 bias of the T cells, the Vbeta4+CD8+ expansion was absent in H-2IA(b)-deficient congenic mice. However, the numbers of cycling cells in the CD4 antibody-depleted mice and mice that are CD4 deficient as a consequence of the deletion of MHC class II, were generally lower. The findings suggest that the IM-like disease is driven both by cytokines provided by CD4+ T cells and by a viral superantigen presented by MHC class II glycoproteins to Vbeta4+CD8+ T cells.


Assuntos
Antígenos Virais/imunologia , Gammaherpesvirinae/imunologia , Mononucleose Infecciosa/imunologia , Superantígenos/imunologia , Animais , Ciclo Celular , Modelos Animais de Doenças , Feminino , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Ativação Linfocitária , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T alfa-beta/fisiologia , Baço/citologia , Linfócitos T/imunologia , Fatores de Tempo
4.
J Viral Hepat ; 15(7): 515-22, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18331250

RESUMO

The Fas / Fas-ligand (FasL) system is an important death signal pathway in the liver. An enhanced local inflammatory response prompted by FasL expression, which contributes to neutrophil recruitment and interleukin-1 beta (IL-1beta) release, seems to be crucial to chronic liver damage, persistence of viral infections, and probably initiation and / or promotion of HCC. In order to evaluate the expression of Fas, FasL, and IL-1beta in different stages of human liver disease and to determine whether hepatitis B virus (HBV) and hepatitis C virus (HCV) infections modulate their expression, also in relation to apoptosis, we examined 87 liver samples obtained from patients with: chronic hepatitis (CH) (n.42), cirrhosis (n.9) and hepatocellular carcinoma (HCC) (n.16) and corresponding peritumoural tissues (n.16); histologically-normal liver (n.4) as controls. Fas, FasL and IL-1beta mRNA were quantified using reverse transcriptase-polymerase chain reaction. The apoptotic index was evaluated by TUNEL analysis. Our data showed a progressive Fas / FasL increase from CH to cirrhosis followed by a decline from the latter to HCC. In histological sections apoptosis was detected in HCC. A significant difference emerged between HCV and HBV-related disease for IL-1beta expression only in CH. A significant positive correlation between IL-1beta and FasL in HCV-related disease (P = 0.014) and an inverse correlation between IL-1beta and Fas in HBV-related disease (P = 0.021) were observed. The different pattern of IL-1beta, Fas and FasL expression found in HCV- and HBV-mediated liver disease, points to a different modulation of immune response B and C virus induced, while the decline in Fas / FasL expression in HCC may be related to defence mechanisms adopted by HCC cells against the immune system.


Assuntos
Apoptose/fisiologia , Carcinoma Hepatocelular/metabolismo , Proteína Ligante Fas/metabolismo , Hepatite B Crônica/metabolismo , Hepatite C Crônica/metabolismo , Neoplasias Hepáticas/metabolismo , Adulto , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Feminino , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Humanos , Hepatopatias/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade
5.
Curr Opin Immunol ; 9(4): 477-83, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9287187

RESUMO

Virus infections cause a much more profound perturbation of the lymphoid tissue than can be accounted for by the exigencies of the antigen-specific response. The extent of this 'immunological dissonance' is seen most dramatically in mice infected with a persistent gamma-herpesvirus, MHV-68. A profile of massive, continuing proliferation of both T and B cells in the lymph nodes and spleen leads to a dramatic increase in the prevalence of a CD62Llow CD8+ T cell subset in the blood, a pattern first detected two to three weeks after intranasal exposure to the inducing virus. This syndrome, which seems identical to human infectious mononucleosis (IM), persists for a further month or more. Part of the IM-like phase of MHV-68 infection reflects the selective expansion of Vbeta4+ CD8+ T cells, with the Vbeta4 effect being apparent for several different MHC class I H-2 types but not in mice that are deficient in MHC class II glycoprotein expression. Depleting CD4(+) T helper cells in MHV-68-infected mice leads to the decreased proliferation of the CD8+ T cells in the spleen and fewer CD62Llow CD8+ T lymphocytes than would be expected in peripheral blood, but fails to diminish the prominence of the V4beta+ CD8+ population. The results so far of this unique experimental mouse model of IM suggest that both cytokine-mediated effects and a viral superantigen are operating to promote the dramatic expansion and persistence of activated CD8+ T cells in the vascular compartment.


Assuntos
Herpesvirus Humano 4/fisiologia , Mononucleose Infecciosa/imunologia , Animais , Antígenos Virais/imunologia , Linfócitos T CD4-Positivos/imunologia , Citocinas/fisiologia , Modelos Animais de Doenças , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Herpesvirus Humano 4/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Ativação Linfocitária , Cooperação Linfocítica , Tecido Linfoide/imunologia , Tecido Linfoide/virologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Superantígenos/imunologia
6.
World J Gastroenterol ; 11(28): 4396-9, 2005 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-16038040

RESUMO

AIM: Trace elements (TE) metabolism is altered in inflammatory bowel diseases. TE (zinc and copper) are constituents of antioxidant enzymes. Iron is involved in the pathogenesis of chronic inflammation. The aim was to evaluate zinc and copper status and the effects of iron manipulation in experimental colitis. METHODS: Twenty-four male Sprague-Dawley rats were divided into four groups: standard diet, iron-deprived diet, iron-supplemented diet, and sham-treated controls. Macroscopic damage was scored. DNA adducts were measured in the colon. Liver and colonic concentration of TE were measured. RESULTS: Macroscopic damage was reduced in iron-deprived groups and increased in iron-supplemented rats. Damage to the DNA was reduced in iron-deprived groups and increased in iron-supplemented groups. Liver and colonic iron concentrations were reduced in iron-deprived and increased in iron-supplemented rats. Liver zinc concentration was reduced after supplementation whereas colonic levels were similar in controls and treated rats. Liver copper concentration was reduced in all the colitic groups except in the iron-supplemented group whereas colonic concentration was increased in iron-deprived rats. CONCLUSION: Iron deprivation diminishes the severity of DNBS colitis while supplementation worsens colitis. Zinc and copper status are modified by iron manipulation.


Assuntos
Colite/dietoterapia , Suplementos Nutricionais , Ferro/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Oligoelementos/farmacologia , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley
7.
Free Radic Biol Med ; 27(11-12): 1284-91, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10641722

RESUMO

UNLABELLED: Chronic hepatitis C virus (HCV) infection is associated with an increased production of reactive oxygen species within the liver that are responsible for the oxidation of intracellular macromolecules. To ascertain whether the increased risk of hepatocellular carcinoma in individuals with chronic HCV infection is related to an accumulation of oxidative DNA damage, the 8-hydroxydeoxyguanosine (8-OHdG) content in the DNA of liver tissue and leukocytes of 87 individuals with HCV- or HBV-related liver disease and of 10 healthy controls was measured. Serum levels of thiobarbituric acid reactive substances (TBARS) were also assessed as an index of lipid peroxidation. RESULTS: The 8-OHdG content in the circulating leukocytes correlated with that of liver tissue (r = 0.618, p < .0004). HCV patients had the highest median 8-OHdG levels (p < .0004). 8-OHdG leukocyte levels in HCV patients were higher than in HBV patients (p < .04) and they significantly correlated with the clinical diagnosis (p < .025), the serum ferritin levels (p < .05), and the amount of liver steatosis (p < .001). No correlation was found with age, gender, history of drinking or smoking, ALT or GGT levels, ESR, alpha-1, or gamma-globulin level and Ishak score. TBARS levels were significantly higher in cirrhotics than in noncirrhotics (p < .01). CONCLUSIONS: The 8-OHdG level in circulating leukocytes is a reliable marker of oxidative stress occurring in the liver of individuals with chronic HCV infection. DNA oxidative damage appears to be an early and unique event in the natural history of HCV-related hepatitis. This injury increases the risk of genomic damage and may be one of the important factors involved in the carcinogenic process in cases of HCV-related chronic liver disease.


Assuntos
Dano ao DNA , Hepatite C Crônica/genética , Leucócitos/química , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Idoso , DNA/análise , DNA/sangue , Desoxiguanosina/análogos & derivados , Desoxiguanosina/análise , Desoxiguanosina/sangue , Fígado Gorduroso/sangue , Feminino , Ferritinas/sangue , Hepatite C Crônica/sangue , Hepatite C Crônica/metabolismo , Humanos , Peroxidação de Lipídeos , Fígado/química , Cirrose Hepática/metabolismo , Masculino , Pessoa de Meia-Idade , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
8.
J Comp Neurol ; 159(2): 257-87, 1975 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1078672

RESUMO

The scanning electron microscope (SEM) was used to investigate the morphology of the neuroepithelial regions of the vestibular ampullary structures in 47 White King pigeons. The specific neural surfaces studied were (1) the cristae ampullares of the vertical and lateral membranous ampullae, (2) the hair cells lining the cristae, (3) the ampullary nerve fibers, and (4) the bipolar cells of the vestibular (Scarpa's) ganglion. Additionally, some observations of the gross anatomical structures of the bony labyrinth are given. Arguments are advanced which show that if the surface area of a given semicircular canal can be projected onto one of the three normal head planes, then that canal can be made to respond to motion in the appropriate plane, provided that the projected area is sufficiently large to achieve a threshold pressure as determined by a generalized form of Groen's equation ('57). With regard to the cristae ampullares, it is hypothesized that their surface areas can be described by means of a revolved catenary, i.e., a catenoid of revolution. (The catenary is found in nature as the approximate shape taken by a flexible cable when it is suspended at two points). The surface area of a catenoid provides a minimum surface of revolution. In the context of a crista, this implies that the given number of hair cells could not be fitted onto a smaller surface area. One advantage of this is that nature is able to utilize a thinner cupula than would be possible with other configurations and therefore an increased sensitivity to cupular motion can be realized. A second important factor is that all hair cells must revolve (by way of cupular motion) about the same centre of rotation in response to angular acceleration. Thus, all of the orthogonally-positioned hair cell tufts on the cristae surface may be stimulated simultaneously by way of a tangential shear. Other arguments show that the classical "swing door" type of cupular motion is not consistent with SEM and other recent observations. Two alternate modes of cupular motion are presented, each of which requires far less energy expenditure than does the "swing door" cupula. The suggestion is then made that, during normal head movements, the cupula behaves as a drum much like the tympanic membrane and that only for large, non-physiological motions does the "swinging door" mode of cupular motion take place. It must be remembered, however, that cupular motions during normal physiological head movements are infinitesimally small (Oman and Young, '72).


Assuntos
Columbidae/anatomia & histologia , Terminações Nervosas/ultraestrutura , Nervo Vestibular/citologia , Vestíbulo do Labirinto/inervação , Animais , Epitélio , Feminino , Masculino , Microscopia Eletrônica de Varredura , Canais Semicirculares/inervação , Vestíbulo do Labirinto/ultraestrutura
9.
Clin Exp Metastasis ; 15(4): 418-25, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9219730

RESUMO

The urokinase-type plasminogen activator (UPA) and its inhibitor PAI-1 are thought to play an important part in gastric cancer (GC) invasion and metastasis. Little is known about the behavior and prognostic impact of the receptor for UPA (UPAR). The aims of the present study were: (1) to measure UPAR, UPA and PAI-1 levels in GC and in non-malignant tissue distant from the tumor (NORM); (2) to evaluate their relationship with histomorphological parameters; and (3) to determine their prognostic value. UPAR, UPA and PAI-1 levels were determined by ELISA in GC and NORM samples from 20 patients with GC undergoing surgery. The GC was also examined in terms of the presence (n = 10) or absence (n = 10) of metastasis, differentiation (five differentiated, 15 undifferentiated) and histotype. Survival was analysed using life table analysis. UPAR, UPA and PAI-1 were significantly higher in GC vs NORM, in the presence of metastasis (UPAR, UPA) and in undifferentiated GC (UPAR, PAI-1). UPAR significantly correlated with UPA and PAI-1. Low levels of UPAR (P = 0.04), UPA (P = 0.007) and PAI-1 (P = 0.02) were associated with a better survival. Our results demonstrate a sharp increase in UPAR in GC and suggest a prognostic role for it. The concomitant activation of UPAR, UPA and PAI-1 in GC confirm the important role of the plasminogen activator system in the process of invasion and metastasis.


Assuntos
Inibidor 1 de Ativador de Plasminogênio/metabolismo , Receptores de Superfície Celular/metabolismo , Neoplasias Gástricas/metabolismo , Adulto , Idoso , Antígenos/análise , Carcinoma/diagnóstico , Carcinoma/metabolismo , Diferenciação Celular , Feminino , Mucosa Gástrica/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Inibidor 1 de Ativador de Plasminogênio/imunologia , Valor Preditivo dos Testes , Prognóstico , Receptores de Superfície Celular/imunologia , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Análise de Regressão , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/secundário , Taxa de Sobrevida , Ativador de Plasminogênio Tipo Uroquinase/imunologia , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
10.
Viral Immunol ; 14(4): 391-402, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11792068

RESUMO

Intranasal infection of mice with murine gamma-herpesvirus 68 (MHV-68) elicits a striking CD8+ T-cell lymphocytosis following the establishment of latency, which includes a marked increased frequency of Vbeta4+ CD8+ T cells. The Vbeta4+ CD8+ T cells do not recognize a conventional viral peptide, but are stimulated by an uncharacterized ligand expressed on latently infected, activated B cells. The selective expansion of Vbeta4+ CD8+ T cells after MHV-68 infection is observed in all mouse strains examined, although the fold-increase varies widely, ranging from less than twofold to greater than 10-fold. The factors controlling the variation are currently undefined. In the current study, CD8+ T cell activation and Vbeta4+ CD8+ T-cell frequencies were analyzed in 18 inbred strains of mice. The data show that the magnitude of the Vbeta4+ CD8+ T-cell response correlates with the degree of CD8+ T cell-activation, and that both major histocompatibility complex (MHC) and non-MHC genes contribute to the magnitude of the activation. Furthermore, the magnitude of the response does not reflect major differences in susceptibility to viral infection and/or corresponding differences in the acute response. Rather the degree of Vbeta4+ CD8+ T cell activation may be determined by differences in levels of expression of the stimulatory ligand at the peak of latency.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por Herpesviridae/imunologia , Rhadinovirus , Infecções Tumorais por Vírus/imunologia , Animais , Feminino , Variação Genética , Ativação Linfocitária , Contagem de Linfócitos , Complexo Principal de Histocompatibilidade/genética , Complexo Principal de Histocompatibilidade/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Endogâmicos NZB , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia
11.
Mol Cell Endocrinol ; 193(1-2): 85-8, 2002 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-12161006

RESUMO

There is considerable evidence that reactive oxygen species (ROS) have a causative role in chronic hepatic injury and cancer development via direct and indirect mechanisms. Estrogens produce free oxygen radicals through redox cycling and affect cell proliferation, also in the liver. We are presently involved in evaluating the possible relationship between estrogens receptor expression, type of receptor, oxidative DNA damage and c-myc in chronic liver disease. The data on DNA adducts, c-myc mRNA and variant estrogen receptor in patients with HCV- or HBV-related chronic liver disease are suggesting that those positive for variant liver estrogen receptor present higher genomic oxidative damage, as reflected in 8-OHdG levels. We are also observing that patients with chronic hepatitis and cirrhosis, when positive for variant estrogen receptor, present higher c-myc m-RNA expression, a factor reportedly associated with increased genomic instability, augmented cytoproliferation and carcinogenesis. Our own and other author's data are shedding new light on estrogen pathophysiology, liver damage and hepatic cancer.


Assuntos
Hepatopatias/metabolismo , Estresse Oxidativo/fisiologia , Receptores de Estrogênio/fisiologia , Animais , Dano ao DNA , Hepatite Viral Humana , Humanos , Hepatopatias/patologia , Hepatopatias/virologia
12.
Eur J Cancer Prev ; 4(2): 181-6, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7767245

RESUMO

This study aimed to identify the factors associated with the development of gastric precancerous changes, in a prospective series of patients undergoing endoscopy. Risk factors and associated mucosal changes were evaluated in 134 endoscoped patients affected by chronic non-atrophic (n = 76) or atrophic gastritis (CAG) (n = 32), with or without intestinal metaplasia (IM), or lacking any major histological changes (n = 26). The following variables were taken into account: age, alcohol consumption, smoking habit, vitamin C intake (using a questionnaire), gastric juice vitamin C (HPLC on gastric juice samples obtained at endoscopy), H. pylori infection, gastric mucosa malondialdehyde (MDA; a measure of free radical production) and extent of CAG in gastric biopsies (only for IM). Tissue MDA levels were significantly higher, and vitamin C levels significantly lower in CAG and IM patients (P = 0.01). Multiple regression analysis showed significant correlations for: CAG vs age (P < 0.02), MDA (< 0.02) and gastric vitamin C (< 0.05); IM vs age (P < 0.0005), CAG (< 0.0005) and MDA (< 0.001). Using stepwise discrimination analysis, the independent variables included in the model were: for CAG, age (P < 0.003), MDA (< 0.05), gastric juice vitamin C (< 0.05); for IM, CAG (P < 0.0005), age (< 0.001), MDA (< 0.03) and vitamin C intake (< 0.05). H. pylori was not included. The major determinants for CAG and IM were age, free radical production (as measured by MDA), vitamin C (for CAG) and vitamin C intake and CAG (for IM).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Gastrite Atrófica/etiologia , Intestinos/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/análise , Doença Crônica , Feminino , Suco Gástrico/química , Mucosa Gástrica/química , Humanos , Masculino , Malondialdeído/análise , Metaplasia/etiologia , Pessoa de Meia-Idade , Estudos Prospectivos
13.
Eur J Cancer Prev ; 1(1): 43-8, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1842683

RESUMO

Exposure to N-nitroso-compounds and aromatic amines, xenobiotics which require an activation in order to exert their genotoxic potential, is causally associated with gastric cancer. We evaluated the capacity of microsome-containing fractions from human gastric mucosa to activate two model carcinogenic compounds. A 9,000 x g supernatant (S9) was obtained from gastric mucosal specimens and, for comparison, from human liver and aroclor-induced and non induced rat liver. The capacity of the S9 to activate N-nitrosopyrrolidine (NPY) and 2-aminofluorene (2AF) to mutagenic metabolites was tested in the Ames/Salmonella reversion assay, while dimethylnitrosamine (DMN) and aminopyrine (AP) demethylation activities were spectrophotometrically evaluated by using an enzymatic assay of the amount of formaldehyde released following the enzymatic demethylation of the corresponding substrates. Results indicate that human gastric S9 fractions may activate 2AF to a genotoxic derivative and are characterized by DMN and AP demethylase activities higher (p < 0.05) than those of human liver, when expressed in mg/protein (p < 0.05). Although the parameters evaluated can only be considered as a partial measure of the general activating capacity toward dietary and environmental procarcinogens, these results suggest that human gastric mucosa may be directly involved in the metabolic activation of these compounds to mutagenic/carcinogenic species.


Assuntos
Carcinógenos/farmacocinética , Mucosa Gástrica/metabolismo , Aminopirina N-Desmetilase/metabolismo , Animais , Arocloros/farmacologia , Citocromo P-450 CYP2E1 , Sistema Enzimático do Citocromo P-450/metabolismo , Relação Dose-Resposta a Droga , Fluorenos/farmacocinética , Humanos , Fígado/metabolismo , Mutagênicos/farmacocinética , N-Nitrosopirrolidina/farmacocinética , Oxirredutases N-Desmetilantes/metabolismo , Pró-Fármacos/farmacocinética , Ratos , Extratos de Tecidos/metabolismo
14.
Clin Chim Acta ; 291(2): 171-87, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10675722

RESUMO

Cysteine and serine proteases are involved in cancer invasion and metastasis. In the past few years we investigated the tissue levels of these proteases in gastric cancer (GC), gastric precancerous changes (CAG), colorectal cancer (CRC) and the plasma and serum levels of proteases in several gastrointestinal tumours, using ELISA methods. Significantly higher antigen levels were found not only in GC tissue but also in CAG with respect to the levels found normal tissue; with respect to CAG, patients with dysplasia had higher levels than patients without dysplasia. The same findings were obtained in CRC. In general protease levels correlated with the major histomorphological parameters, such as grading and histotype in GC as well as in CRC. Tissue protease levels had a strong prognostic impact in GC, in which UPA was singled out by multivariate analysis as the major prognostic factor, and CRC. The plasma levels of urokinase-type plasminogen activator (UPA) and the serum levels of cathepsin B were significantly increased in patients with gastrointestinal tumours. In conclusions, cysteine and serine proteases may have a part not only in GC and CRC invasion and metastasis, but also in the progression of gastric precancerous changes into cancer. They are strong prognostic factors in GC and CRC. These proteases may also have a role as tumour markers in the early diagnosis of gastrointestinal tract tumours.


Assuntos
Endopeptidases/metabolismo , Neoplasias Gastrointestinais/enzimologia , Biomarcadores Tumorais , Neoplasias Gastrointestinais/patologia , Humanos , Hidrólise , Lesões Pré-Cancerosas/enzimologia , Lesões Pré-Cancerosas/patologia
15.
J Invest Surg ; 14(6): 303-12, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11905498

RESUMO

Reperfusion injury represents a key event leading to graft nonfunction. Maintaining adequate nitric oxide levels and stimulating vasodilator synthesis can probably minimize endothelial damage. The aim of this study was to investigate the effect of L-arginine, a substrate of nitric oxide synthesis, and oligotide, a promoter of prostacyclin synthesis, on liver function and morphology after warm ischemia-reperfusion injury. After constructing a side-to-side portacaval shunt, ischemia was induced by clamping the hepatic hilum for 2 h above the shunt, in 19 female pigs divided into a control group (n = 7), an L-arginine treatment group (n = 6), and an oligotide treatment group (n = 6). Liver function tests and measurements of serum and red blood cell malondialdehyde and plasma nitric oxide levels were performed before reperfusion and at 1, 10, 60, and 120 min after reperfusion. Liver biopsies, taken before reperfusion and at 30 min and 7 days after reperfusion, were analyzed for tissue malondialdehyde, histological-ultrastructural features, and apoptosis evaluation. Thirty minutes after reperfusion, liver malondialdehyde, sinusoidal congestion, necrosis, and apoptosis were significantly lower in the L-arginine group than in the controls (p < .05). On postoperative day 7, tissue malondialdehyde decreased, while plasma nitric oxide and hepatocyte glycogen content were increased in the L-arginine group compared to controls (p < .05). This study demonstrates the protective effect of L-arginine on hepatic lipoperoxidation and liver morphology in a pig model of warm ischemia-reperfusion injury. The increased plasma levels of nitric oxide a week after ischemia-reperfusion injury support the hypothesis that it has a role in preventing liver damage. The same beneficial effect was not confirmed for oligotide.


Assuntos
Arginina/farmacologia , Isquemia/patologia , Fígado/irrigação sanguínea , Oligodesoxirribonucleotídeos/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Apoptose , Feminino , Isquemia/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/ultraestrutura , Óxido Nítrico/análise , Óxido Nítrico/fisiologia , Substâncias Protetoras/farmacologia , Suínos
16.
Biol Trace Elem Res ; 47(1-3): 193-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7779547

RESUMO

In an attempt to elucidate further the mechanisms involved in alcohol-mediated liver damage and the correlation between alcohol and viruses in chronic liver lesions, we determined the levels of liver glutathione (GSH), thiobarbituric acid reactive substances (TBARS), iron (Fe), and zinc (Zn) in 31 patients with chronic viral hepatitis (CAH), 6 with alcohol-related chronic hepatitis (CALD), 6 with alcoholic cirrhosis (AC), 8 with primary biliary cirrhosis (PBC), and 10 healthy controls (C). Liver GSH was significantly lower in CALD and AC patients (p < 0.005). TBARS levels were significantly higher in CAH, CALD, and PBC patients (p < 0.001, < 0.02, and < 0.001, respectively). In CAH patients, alcohol consumption correlated inversely with GSH and directly with TBARS (p < 0.05). Patients with both CAH and alcohol abuse had a further reduction in liver GSH levels (p < 0.005). Tissue levels of Fe were significantly increased in CALD and AC patients with respect to controls and CAH patients, whereas no significant difference was observed in Zn. These data confirm that patients with chronic ethanol exposure reveal a depletion in liver GSH content clearly correlated with an increase in lipid peroxidation and Fe liver storage. On the other hand, these findings appear to suggest no significant change in Zn levels in chronic hepatitis.


Assuntos
Glutationa/metabolismo , Hepatite Viral Humana/metabolismo , Ferro/metabolismo , Peroxidação de Lipídeos , Cirrose Hepática Alcoólica/metabolismo , Cirrose Hepática Biliar/metabolismo , Fígado/metabolismo , Feminino , Glutationa/análogos & derivados , Dissulfeto de Glutationa , Humanos , Masculino , Valores de Referência , Caracteres Sexuais , Substâncias Reativas com Ácido Tiobarbitúrico/análise
17.
Orv Hetil ; 137(30): 1637-41, 1996 Jul 28.
Artigo em Húngaro | MEDLINE | ID: mdl-9019701

RESUMO

Cysteine proteases (cathepsin B and L), the serine protease urokinase-type plasminogen activator and its inhibitor type-1 play an important part in cancer invasion and metastasis. The authors determined the protease concentrations in gastric cancer tissues, using the ELISA method, in patients with gastric cancer. They evaluated the prognostic role of proteases and the relationship that these proteases may have with other histomorphological prognostic parameters such as tumor staging, grading, histotype, Borrmann classification. The Cox survival analysis showed that cathepsin B (p = 0.002), urokinase-type plasminogen activator (p = 0.0001) and the inhibitor type-1 (p = 0.0004) significantly correlated with poor prognosis. The tumor staging, grading, Borrmann classification correlated also significantly with survival time. Urokinase-type plasminogen activator was selected as the single independent variable in the Cox model (p = 0.0001).


Assuntos
Cisteína Endopeptidases/metabolismo , Serina Endopeptidases/metabolismo , Neoplasias Gástricas/enzimologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico
18.
Orv Hetil ; 136(12): 643-7, 1995 Mar 19.
Artigo em Húngaro | MEDLINE | ID: mdl-7535908

RESUMO

Hepatocellular carcinoma is a tumor with high mortality. Adequate oncological therapy is essential to modify the poor prognosis. Transcatheter arterial chemoembolisation has been proposed as a useful and well-tolerated treatment for unresectable carcinoma. In the study 51 patients with unresectable carcinoma (mean age 61.6, range 45-81, Child-Pugh A = 34 patients, Child-B = 13, Child-C = 4; Okuda I = 33 patients, Okuda II = 18) underwent chemoembolisation. A total of 122 procedure were performed, with a median number of 2.4 (range 1-6) per patient. One and two year survivals are 91% and 74% respectively (Child-A: 100% and 82%; Child-B: 100% and 63%; Child-C 0% at 1 year). The difference among the 3 groups is statistically significant (p = 0.001). Median overall survival is 20 months, with 22, 20 and 6 month in Child-A, B and C patients respectively (p = 0.006). Commonly reported side effects and biochemical changes included: fever, pain and increased serum amylase, transaminase levels. One patient developed a liver abscess and died of liver failure. In addition, in 18 patients (35%) mild to severe changes in glucose metabolism were also observed. Mild hyperglycemia was observed in 14 patients, with severe derangement in 4 patients (8%). It is suggested that careful evaluation of glucose metabolism is advisable in patients being considered for chemoembolisation. Their results confirm the usefulness of chemoembolisation in Child-A and B patients with unresectable hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Cateterismo Periférico , Feminino , Humanos , Hungria/epidemiologia , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Paliativos
19.
Orv Hetil ; 136(25): 1315-8, 1995 Jun 18.
Artigo em Húngaro | MEDLINE | ID: mdl-7596589

RESUMO

Cathepsin B and cathepsin L--cysteine proteinases--may play an important role in cancer invasion and metastasis. The authors determined tissue antigen concentrations of cathepsins, using the ELISA method, in 25 patients with gastric cancer (17 males, 8 females, mean age 62, range 31-84). They evaluated the possible relationship that these proteinases may have with the presence of metastases, differentiation and histotype. Significantly higher cathepsin B and cathepsin L antigen levels were found: 1. in gastric cancer tissues vs. normal tissues distant from tumors (CATB: p < 0.05, CATL: p < 0.005); 2. in diffuse vs. intestinal type cancers (p < 0.05); 3. in patients with poorly vs. well-differentiated cancers (p < 0.05); in gastric cancers with vs. without metastasis (p < 0.05). Their results confirm that cathepsin B and L play an important role in gastric cancer invasion and metastasis. Considering the significantly higher cathepsins detected in cancers with metastasis, a poor differentiation and of diffuse histotype, these proteinases could be useful for identification gastric cancer patients with a poor prognosis.


Assuntos
Catepsina B/química , Catepsinas/química , Cisteína Endopeptidases/metabolismo , Endopeptidases , Neoplasias Gástricas/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Catepsina L , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/patologia
20.
Orv Hetil ; 136(29): 1545-9, 1995 Jul 16.
Artigo em Húngaro | MEDLINE | ID: mdl-7637971

RESUMO

This retrospective study was undertaken to evaluate the diagnostic usefulness of 244 sonographically guided fine- needle aspiration biopsy in 226 patients with ultrasonographically suspected hepatic malignant lesions. A final diagnosis of malignancy was established in 166 cases (73%) (145 hepatocellular carcinoma, 21 metastasis); benign lesions were aspirated in 60 cases (27%). The diagnostic sensitivity of this technique was 93%, with 100% specificity. When both cytology and microhistology were obtained, the positive correlation of the two techniques was 80% In the series of 244 fine-needle aspiration biopsy the authors had only one acute complication. They report one case of needle tract tumor seeding after biopsy. These results confirm the usefulness of sonographically guided fine-needle aspiration biopsy in diagnosing malignant hepatic tumors. The procedure is simple, safe, free of important side effects. The authors believe that ultrasound guided fine-needle aspiration biopsy represents the first choice of invasive technique in the assessment of hepatic focal benign lesions and malignant tumours.


Assuntos
Biópsia por Agulha/instrumentação , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/ultraestrutura , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/ultraestrutura , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/ultraestrutura , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ultrassonografia
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