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Biomedical subjects

A Pár

Publications and source records attributed to A Pár.

At least 19 recordsLinked to original sources
PubMed2004

Co-infections with hepatitis G and TT virus in patients with chronic hepatitis C in Hungary.

The significance of co-infections with novel hepatitis viruses Hepatitis G (GBV-C, HGV) and TT virus (TTV) in chronic hepatitis C is not clear. We determined the prevalence of HGV RNA and TTV DNA in chronic hepatitis C patients and in asymptomatic hepatitis C virus (HCV) carriers, and assessed the influence of these agents on the course of HCV infection. Seventy-seven patients with chronic hepatitis C--50 of them treated with interferon (IFN)--and 33 HCV carriers with normal alanine aminotransferase have been investigated. Previous HBV infection was detected by testing serum HBsAg and aHBc. HGV RNA and TTV DNA were detected by PCR. In the healthy population, the prevalence of anti-HCV was 0.3%, HGV RNA 8.0% and TTV DNA 18.5%. In chronic hepatitis C HGV RNA occurred in 9.09% and TTV DNA in 40.25% of cases. In IFN-treated patients with sustained remission, the frequency of TTV was 20% vs. 45.7% found in non-responders. Among asymptomatic HCV-carriers, the prevalence of HGV RNA was 9.09% and TTV DNA 75.7%. Neither HGV RNA nor TTV DNA had apparent effect on the HCV infection. TTV was detected with the lowest frequency in persons with sustained remission due to IFN, suggesting antiviral effect of IFN on TTV.

Adolescent↗
PubMed2001

[Molecular genetics and gene therapy in diseases of the esophagus, stomach, colon and pancreas].

There has been a major improvement in our knowledge in the area of molecular genetics in the past 20 years. It has become evident that genetic factors are important in the initiation, progression and prognosis of most diseases. Many studies addressed the issue of tumorigenesis, which provided insight into the molecular basis of the sequencional development of cancer, driven by the accumulation of genomic defects. Most of the neoplasms are genetically heterogeneous, independent pathways and simultaneous tumorigenesis may exist within the same organ. As some mutations exist in benignant and also in malignant conditions, it is an important challenge to define the molecular characteristics of significant versus non-significant lesions. A new form of therapeutic intervention is gene therapy. During the next decade it will likely play an increasing role in clinical practice and particularly in the treatment of cancer.

Animals↗
PubMed2001

Mechanisms of action of retinoids in gastrointestinal mucosal protection in animals, human healthy subjects and patients.

UNLABELLED: Retinoids prevent chemically induced gastric mucosal damage without inhibiting gastric acid secretion ("nutritional gastric cytoprotection"). The gastroprotective effects of retinoids do not depend on 1) vitamin A activity; 2) number of unsaturated double bonds; 3) the presence of a characteristic chemical structure of their terminal components; however, they depend on 1) intact vagal nerve and 2) adrenals in experimental animals. The gastric cytoprotective effect of retinoids produces a dose-dependent inhibition of ATP-transformation into ADP. It also increases the transformation of ATP into cAMP. Other features of these gastric cytoprotective effects of retinoids include: 1) The retinoid-induced gastric mucosal protection differs from that of PGs; 2) The cAMP is an intracellular signal in the development of gastric mucosal damage produced by chemicals (e.g., ethanol, HCl, indomethacin) and in the protection of gastric mucosa induced by retinoids (but not by PGs); 3) The gastric mucosal protection induced by retinoids and gastric mucosal permeability can be separated in time. The existence of gastric mucosal protection can be demonstrated in healthy persons (against indomethacin treatment), in patients with gastric ulcer (GU) and duodenal ulcer (DU) without any inhibition of gastric acid secretion. The serum levels of vitamin A and zeaxanthin were significantly decreased in patients with chronic gastrointestinal (GI) inflammatory diseases (e.g., terminal ileitis, ulcerative colitis), colorectal polyposis, and different (e.g., esophageal, gastric, pancreatic, hepatocellular and colorectal) malignant diseases. The serum levels of vitamin A provitamins were unchanged and their GI mucosal protective effects do not depend on vitamin A activity. CONCLUSIONS: 1) Abundant experimental and human observations clearly proved the defensive role of retinoids in the GI tract; 2) There is a correlation between the a) scavenger properties of retinoids vs. intact vagal nerve; b) scavenging properties vs. intact adrenals. 3) The GI mucosal protective effect of retinoids is correlated with biochemical changes in the GI mucosa.

Adenosine Diphosphate↗
PubMed2001

[Gastrointestinal immunology].

The paper is devoted to the actual questions of gastrointestinal immunology. In the first part, structure and function of gut-associated mucosal tissue (GALT), including the role of secretory immunoglobulins and importance of oral tolerance are shown. In the second part, the pathogenesis of unknown origin gastrointestinal and liver diseases (gluten sensitive enteropathy, inflammatory bowel diseases, autoimmune liver diseases, autoimmune pancreatitis) is described. Then the immunology of some gastrointestinal infections (Helicobacter pylori, hepatitis virus B and C, and HIV) and of alcoholic and drug induced, liver diseases is briefly summarized.

Animals↗
PubMed2000

[Hepatitis C virus infection and B-cell non-Hodgkin's lymphoma].

Oncogenesis is a multifactorial process in which environmental, genetical and infectious factors may be of importance. Specific viruses are supposed to have etiological role in about 15% of human tumors. Recently the B-cell proliferation inducing effect of the hepatotropic and lymphotropic hepatitis-C virus (HCV) came into the limelight based on the high prevalence of HCV positivity in B-cell non-Hodgkin's lymphoma (NHL) patients. The aim of the authors was to establish the prevalence of HCV infection in NHL patients. Paralelly the HBV, CMV and EBV markers, and the alterations of the humoral immune response (immunoglobulins, cryoglobulins, rheumatoid factor) were determined. 42 patients (24 male, 18 female; the mean age: 54.1 years, range 22-80 years) classified as 16 indolent (low risk), and 25 aggressive (intermediate risk) NHL and one with very aggressive Burkitt's lymphoma, according to the modified REAL classification were examined. Enzyme-linked immunosorbent assay (ELISA) for HBsAg and anti-HCV, HBsAg, anti EBV, anti CMV, furthermore polymerase chain reaction (PCR) for HCV-RNA were used. Anti-HCV was found in 6/42 NHL patients (14.3%), while anti-HCV and/or HCV-RNA PCR positivity revealed on overall HCV infection in 10/42 (23.8%) patients. None of them were HBsAg positive. Our findings support the hypothesis, that HCV might have an aetiological role in the lymphoproliferation leading to B-cell NHL.

Adult↗
PubMed2000

[Are the hemochromatosis (HFE) gene mutation and hepatitis C virus (HCV) infection risk factors for porphyria cutanea tarda?].

As it is not clear whether mutations in hemochromatosis gene (HFE) and hepatitis C virus (HCV) act independently in the pathogenesis of porphyria cutanea tarda (PCT), and prevalence of both risk factors reveals a great variety in different parts of the world, PCT patients from our Central East European country were investigated for this aspect. The occurrence of the C282Y and H63D mutations in HFE gene were determined in 19 PCT patients and compared with the reported control frequencies. Furthermore, the presence of HCV infection was determined and related to the patients' HFE status. The C282Y mutation was found in 3/19 cases (one patient was homozygous and two heterozygous), with an 10.5% allele frequency (vs. 3.8% control) (p < 0.05). Five patients were heterozygous for the H63D mutation, allele frequency 13.1%, which did not differ from the reported control prevalence of 12.3%. Six patients (31.7%) were HCV-RNA positive, out of the six one was heterozygous for H63D mutation and one was compound heterozygous. HCV infection and HFE C282Y mutations may probably be independent predisposing factors for development of PCT in Hungarian patients.

Adult↗
PubMed2000

[Oxidative stress and antioxidant defense in alcoholic liver disease and chronic hepatitis C].

In the past decade it became accepted that free radicals, lipid peroxidation and antioxidant defense play a role in various tissues damages, thus in certain liver diseases as well. Since only limited data have been reported concerning the oxidative stress in viral hepatitis, a comparative study was performed in patients (pts) with chronic hepatitis C and alcoholic liver disease. In addition, the effects of a flavonolignan drug silymarin were assessed. 10 pts with chronic hepatitis C, 5 pts with alcoholic hepatitis and 13 pts with alcoholic cirrhosis have been investigated. Biochemical liver tests (serum bilirubin, aminotransferases, ALT, AST, lactate dehydrogenase (LDH), pseudocholinesterase, prothrombin), malandialdehyde (MDA) levels in plasma and red blood cell (RBC) hemolysate, superoxide radical generating capacity of stimulated polymorphonuclear granulocytes (PMN), plasma concentrations of reduced (GSH) and oxidized (GSSG) glutathione, vitamin A, luteine and beta carotene, furthermore RBC superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase activities were determined. The level of plasma MDA--as the marker of lipid peroxidation--was highest in alcoholic cirrhosis (five times of normal) (p < 0.05), the RBC hemolysate MDA was most elevated in chronic hepatitis C (p < 0.05). The mean PMNs' superoxide radical generating capacity was 116.6% of normal control in alcoholic hepatitis, where the mean GSH level was the lowest (89.8% of normal). Plasma vitamin A content was lowest in alcoholic cirrhosis (68% of control) (p < 0.05). SOD activity was elevated in both chronic hepatitis C and alcoholic cirrhosis, where GPx activity was decreased (p < 0.05). There was a correlation between LDH and SOD activities (r = 0.77, p = 0.015). Silymarin treatment of one month duration resulted in normalization of serum bilirubin in 55% of treated pts, AST became normal in 45%, and RBC hemolyzate MDA level normalized in similar rate. A significant increase in both GSH and retinoids was found. Alterations in oxidative stress and antioxidant defense system were shown in chronic hepatitis C, not only in alcoholic liver disease. The parameters of lipid peroxidation and antioxidant defense may be useful surrogate markers for monitoring pts with liver disease during hepatoprotective treatment.

Adult↗
PubMed2000

Changes in the acute phase complement component and IL-6 levels in patients with chronic hepatitis C receiving interferon alpha-2b.

In order to study the effect of interferon alpha on the levels of acute phase complement proteins in vivo, serum concentrations of C9 and C1-inhibitor (C1-INH) were measured in patients with chronic hepatitis C before and 3 months after the beginning of interferon alpha2b therapy. Serum levels of the activation product of terminal complement pathway, C5b-9, HCV RNA and IL-6 were also determined. IFN alpha treatment significantly (P<0.0001) increased the serum concentrations of both complement proteins. C5b-9 levels were found to significantly decrease during the same period of time. When the patients were divided into responders or non-responders (more or less than 50% decrease in plasma HCV RNA concentrations) C9 and C1-INH levels were elevated only in the responder patients. There was no correlation between the changes of IL-6 levels or the amounts of IFN alpha administrated on one hand, and the changes in the complement protein levels on the other. These findings suggest that the marked increase in the serum concentrations of the acute phase complement proteins is a secondary phenomenon due to the IFN alpha-caused diminution of the viral load and the resulting immune complex-induced complement activation.

Acute-Phase Proteins↗
PubMed2000

[Treatment of alcoholic liver diseases. Abstinence, nutritional support, drug therapy, liver transplantation].

The review summarizes clinically established treatment forms of alcoholic liver disease in four main chapters: abstinence, nutritional supportation, drug therapy and liver transplantation are discussed. Drug therapy is described according to the three types of alcoholic hepatopathies (fatty liver, hepatitis and cirrhosis). Early diagnosis and treatment depending on the severity and stage of alcoholic liver disease are of importance for the attempts to retard progression and improve prognosis.

Alcohol Deterrents↗
PubMed2000

C5b-9 and interleukin-6 in chronic hepatitis C. Surrogate markers predicting short-term response to interferon alpha-2b.

BACKGROUND: Available data and our observations suggest that elevated levels of interleukin (IL)-6 and -10 and some complement parameters may be associated with a poor response to IFN alpha. We evaluated how baseline levels of C5b-9, IL-6, and IL-10 influence the outcome of IFN alpha treatment. METHODS: Fifty-one patients with established chronic hepatitis C were enrolled and treated with IFN alpha-2b. Before and after a 12-week-IFN-treatment (3 MU or 5 MU tiw) serum levels of IL-6, IL-10, C5b-9 and RNA of hepatitis C virus (HCV) were assessed. Sera of 46 sex- and age-matched, healthy blood donors served as control. RESULTS: While two-thirds of patients was considered 'responder', 14 patients had no significant decrease either in HCV RNA or in ALT levels. In the responder's group lower baseline levels of IL-6 and C5b-9 were found than those in the 'non-responder' group. As a result of IFN therapy HCV RNA and C5b-9 levels significantly decreased. While the serum concentration of IL-6 increased during the follow-up period, regarding IL-10, no change was observed. In patients with 'low' baseline levels of C5b-9 (<2053 ng/ml) IFN alpha resulted in a significantly (P = 0.0005) higher decrease in HCV RNA level. Regarding 'low' IL-6 values (< 1.47 pg/ml) similar but somewhat less significant (P = 0.0039) difference was found if the change of HCV RNA was investigated. The odds ratio of patients with low IL-6 and/or C5b-9 to responding to IFN alpha treatment was almost 10 times (CI: 9.1 (1.8-50.9)) higher as compared with patients without 'low' levels of these parameters. CONCLUSION: Our data suggest that serum level(s) of IL-6 and/or C5b-9 taken prior to the initiation of IFN treatment may serve as surrogate marker(s) in evaluating patients with chronic hepatitis C whether to get IFN alpha in monotherapy or to consider having combination therapy in the form of IFN alpha-ribavirin.

Adult↗
PubMed2000

Gastrointestinal tract as a part of immune defence.

The paper is devoted to reviewing the function of gastrointestinal mucosal immune system. Gut-associated lymphoid tissue (GALT) provides the host with protective mechanisms against invasion by potential pathogens across the mucosal surface, and on the other hand, it plays a role in the development of induced tolerance against harmless products of digestion and the normal intestinal flora, all of which are potentially immunogenic. First the organization of GALT, its afferent and efferent limbs are described, then the normal B cell homeostasis and finally the induced oral tolerance are discussed. Knowledge of mechanisms of mucosal immune response is essential to complete understanding of the pathogenesis and treatment of inflammatory gastrointestinal diseases as well.

Digestive System↗
PubMed2000

Pathogenesis and treatment of autoimmune hepatitis and chronic viral hepatitis B and C.

Immune mechanisms play a role in autoimmune hepatitis which is considered as "idiopathic" inflammatory liver disease of unknown etiology. However, even chronic viral hepatitis B and C have also features suggesting the importance of immunopathogenesis in their development. This paper discusses the major genetical and immunological factors in the above-mentioned chronic liver diseases and briefly summarizes their therapeutic modalities.

Hepatitis B, Chronic↗
PubMed1999

[Percutaneous drainage in the treatment of accidentally discovered hydatid cyst in patients with polycystic liver].

This article report on a not very well-known therapeutical procedure used among only fairly diagnosed cases based on international and Hungarian experiences. In Hungary echinococcus cyst of the liver is mostly treated surgically (the average mortality rate of liver resection is 0-6.3%). In many places the percutan puncture and drainage are contraindicated in case of echinococcus cysts. The authors assert that the percutaneous treatment of echinococcus cysts in proper technical and methodic circumstances in safe regarding the previous studies and their own data obtained of a few cases, and describe the technique and raise some question in them. Drainage treatment is very well tolerated by the patients it reduces the duration (of time) and the cost of the hospitalization.

Aged↗
PubMed1999

[Adenomyomatosis of the gallbladder].

A 64-year-old male patient was reported, surveying radiology and pathology of the adenomyomatosis. The authors emphasize the role of high resolution ultrasound and computer tomography in the diagnosis of gallbladder adenomyomatosis. Intramural cystic formation (anechoic diverticula) with echogenic foci and/or reverberation artifacts together with a full or a partial thickening of the gallbladder's wall was considered as the diagnostic criteria of the ultrasound examinations. They assist in finding the proper way among the difficulties of the different diagnosis, in the same time call the attention for the frequently misdiagnosed cases.

Adenomyoma↗
PubMed1999

[Interferon therapy of chronic viral hepatitis in Hungary: 5-year experience. A multicenter study].

In Hungary over the past 5 years more than thousand patients with chronic viral hepatitis have been examined and included in a treatment program with interferon (IFN) at 16 major hepatology centers, using unified diagnostic and therapeutical criteria. Authors give an account of their experiences on the clinical features of patients with chronic viral hepatitis and report the results of the treatment with IFN. According to the rules and availability of IFN for patients with chronic viral hepatitis in the country, virtually the entire Hungarian population with this diseases who required IFN therapy have been included. A total of 94 patients suffered from hepatitis B virus (HBV) infection, in addition 11 HBV + hepatitis Delta virus (HDV), 24 HBV + Hepatitis C virus (HCV) related liver disease, and 993 had chronic hepatitis C. IFN therapy for chronic HBV hepatitis consisted of IFN 5 MU thrice weekly for 6 months, and resulted in 33% seroconversion and sustained remission with 14% HBsAg clearance. For chronic hepatitis C treatment protocols (dose of IFN and duration of therapy) have changed with the time (from a weekly dose of 3 x 3 MU IFN for 6 months, to 3 x 3 MU for 12 months), and even a combination with ribavirin has been introduced. Although the therapeutic results showed a gradual improvement form a 13% sustained response over 22% in the first and second periods, respectively, differences were most significant with the advent of the combination therapy, that resulted in 36% remission rate. Only fibrosis in histology and baseline pretreatment HCV-RNA level appeared as predictors of response in chronic hepatitis C. Neither age nor gender did influence the outcome, but longer duration of treatment and higher total dose of IFN resulted moderately higher sustained remission rates. The experiences are in accordance with findings of suboptimal efficacy of IFN monotherapy reported worldwide and emphasize the need of seeking for newer and combination therapeutic modalities for these chronic viral diseases.

Adolescent↗