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Biomedical subjects

L Ortona

Publications and source records attributed to L Ortona.

At least 109 records · Page 6Linked to original sources
PubMed1983

Incidence of antibodies against rabbit liver specific lipoprotein (RLSP) in chronic active hepatitis.

In chronic active hepatitis (CAH) evidence exists that circulating autoantibodies against liver specific lipoprotein (LSP) could play a role in the development of hepatocellular injury. We evaluated the presence of autoantibodies in CAH against LSP using rabbit LSP, as antigen in a radioimmunoprecipitation test. Fifty-one patients with histologically diagnosed CAH were investigated. Among these 16 were HBsAg+, 15 were HBsAg-/anti-HBc+, 10 were non-A, non-B, 10 were autoimmune CAH. Anti-LSP were detected in six of 16 (37%) HBsAg+ (mean titre of 1:198); four of 15 (33%) HBsAg-/anti-HBc+ (mean titre of 1:246); two of 10 (20%) non-A, non-B (mean titre of 1:185); seven of 10 (70%) autoimmune CAH (mean titre of 1:307). No correlation was evident between the titre of anti-LSP and the values of AST, bilirubin or IgG. The findings seem to be consistent with the following conclusions: (a) CAH patients develop an humoral immune response to determinants in LSP which are not species specific. This is further evidence that rabbit LSP could be considered a suitable alternative to the human preparation in evaluation of autoimmunity in CAH and (b) the different behaviour of anti-LSP in patients with viral CAH (B, non-A, non-B) in respect of patients with autoimmune CAH suggests a variable importance of these antibodies in the mechanism of ongoing liver cell injury according to the various types of CAH.

Animals↗
PubMed1982

[Hepatitis A, B, and non-A, non-B. Epidemiologic, clinical and differential immunologic aspects].

The results of a clinical and epidemiological investigation on the differential characters of hepatitis A, hepatitis B and hepatitis non-A, non-B (NANB) are reported. A more accurate nosological definition of NANB hepatitis has showed the following characters: on incubation period intermediate between hepatitis A and hepatitis B; transmission similar to hepatitis B; onset of the disease and clinical features similar to hepatitis A; jaundice of lower intensity than hepatitis A; lower IgM levels than hepatitis A; a remarkable tendency to evolve towards chronic liver disease, higher than hepatitis A and hepatitis B.

Animals↗
PubMed1981

[Serological diagnosis of hepatitis A: determination with the RIA of anti-A specific IgM after absorption of IgG with protein A of Staphylococcus aureus].

The research of specific IgM anti virus A (anti HAV-IgM), by absorbtion of IgG with Staphylococcus aureus A protein, has been conducted in the sera of 49 patients with acute hepatitis non B (HBsAg negative). Twenty-nine of these patients (59.2%) were anti HAV-IgM positive and therefore were diagnosed as viral hepatitis A, while twenty (40.8%) were anti HAV-IgM negative and were considered as non A-non B hepatitis. In the present work the practical utility of the detection specific IgM by absorbtion with A protein is discussed also in respect of the more expensive and less sensitive technique of gel fractionation of the sera. In addition our preliminary results document a decreasing incidence of viral hepatitis A in all the cases seen in the period 1978-1979. This event, which needs further investigations, could also be due to a more significant incidence of non A-non B hepatitis, probably as consequence of increasing drug-addiction.

Antibodies, Viral↗
PubMed1981

Direct and serum-induced lymphocytotoxicity against rabbit hepatocytes in chronic active hepatitis.

The direct and the serum-induced lymphocytotoxicity against cultured rabbit hepatocytes were evaluated in 25 patients with chronic active hepatitis (CAH) (15 HBsAg+). Twelve out of fifteen HBsAg+ and nine out of ten HBsAg- patients have shown an increased cytotoxicity for rabbit hepatocytes. Moreover the sera of the same patients were able to induce a significant cytotoxicity in normal lymphocytes against rabbit hepatocytes. The addition of LSP was able to inhibit the cytotoxic reaction for rabbit hepatocytes in all cases with positive cytotoxic index. Indeed, the results we have obtained are the following. a) A significant lymphocytotoxicity for rabbit hepatocytes exists in patients with CAH, and this is unrelated to HBsAg status. b) A linear correlation ( r = 0.88; p less than 0.001) exists between the direct and the serum-induced lymphocytotoxicity in CAH hepatitis. c) The cytotoxicity to rabbit hepatocytes seems to be an antibody mediated process and the target antigen seems to be LSP.

Adult↗
PubMed1980

[Detection of virus A antibody through epidemiology and diagnosis of hepatitis A].

In the present work the Authors report the results of the research of HAAb in 383 subjects living in Rome with negative history for hepatitis (divided for age, sex and occupation) and in 64 acute non B hepatitis (HBsAg-). In the latter, the titer of HAAb was determined at the beginning and later during the course of the disease. A fractionation of 13 sera of these patients was done and the type of specific immunoglobulin was determined. Among the subject with negative history for hepatitis, 68.9% was positive during first 6 months of age 6.2% from 6 months to 5 y.o., 27.6% from 6 to 12 y.o., 45.4% from 12 to 17 y.o., 76.8% from 18 to 25 y.o., 82.2% from 26 to 45 y.o., 90.2% from 46 to 65 y.o.. There was no statistically significant difference either between males and females, or among various occupations. Among the 64 patients with non B hepatitis, 25 (39%) were hepatitis A (because they showed either a seroconversion for HAAb or a positive HAAb-IgM); 12 (18.7%) were non A-non B hepatitis because HAAb negative or HAAb positive but negative for HAAb-IgM; while 27 (42.2%) were impossible to classify because they showed a positivity for HAAb but not a seroconversion during the disease. The limit of the determination of HAAb and the utility of the research of IgM antibody for the diagnosis of hepatitis A are discussed.

Adolescent↗
PubMed1980

Immune response to rabbit liver-specific lipoprotein in acute viral hepatitis.

A serial prospective study of cell-mediated immunity to rabbit liver-specific lipoprotein (RLSP) has been done in 26 patients with acute viral hepatitis (AH) (18 HBsAg+ and eight HBsAg-) using a lymphocyte transformation test. An increased stimulation index was recorded in 56% of HBsAg+ cases and in 63% of the HBsAg- group at the first determination within 2 weeks of presentation. A progressive return to normal values was observed during the course of the disease. In one patient, however, the stimulation index remained high at 6 months after presentation and liver biopsy showed the appearance of chronic active hepatitis. Results within the normal range of values were observed when a macromolecular kidney protein fraction was used as antigen: further evidence of an organ-specific component in RLSP preparation to which the immune response seems to be directed. These findings demonstrate the existence of a common and time-limited sensitization to RLSP in acute viral hepatitis irrespective of HBsAg status. It is suggested that RLSP may be a useful alternative to human LSP in evaluating immune reactions in liver diseases.

Acute Disease↗
PubMed1979

[Further observations on the HBeAg-HBeAb system in the course of hepatitis and in HBsAg carriers].

The HBeAg-HBeAb system has been studied by means of the microimmunodiffusion technique on agar in patients suffering from acute hepatitis at various stages of the disease, in patients with chronic liver diseases and in asymptomatic carriers of HBsAg. The results correlate the presence of HBeAg with the state of the disease (initial phase of acute or chronic hepatitis) and the presence of HBeAb with clinical cure of an acute hepatitis or with the condition of healthy carrier. It is a personal impression also that an HBsAg + hepatitis can be cured more rapidly the better the immune response expressed by the appearance of HBeAb, and that a lacking or deficient immune response to HBeAg may underlie the chronic course of the disease. Emphasis is also laid on the early disappearance of HBeAb in patients with acute hepatitis, this being matched by its persistence in asymptomatic carriers of HBsAg. In this regard, the first results reported here on the identification of the immune globulin class to which the HBeAb belongs would appear to confirm the hypothesis that the anti-e response is of IgM type in acute hepatitis and of IgG type in HBsAg carriers.

Antibodies, Viral↗
PubMed1979

[Hepatitis and drug addiction: clinical and immunological studies].

The association drug addiction-hepatitis has so increased in recent years to represent a social epidemiological and clinical problem all over the world. Although the clinical picture of hepatitis is already well defined in drug-abusers, it remains to be completely understood the mechanism responsible for the significant incidence of progression from acute to chronic hepatitis in this population. The viral infection, the drug itself, the drug contaminants, the immunological defects (cellular and/or humoral) may be considered as possible contributing factors to this event. For this reason the Authors have performed an immunological study either in a group of drug-abusers with acute and chronic hepatitis, or in a group of 82 "asymptomatic" drug addicts without a history of liver diseases. The results of this study are the following: - In all the drug-addicts considered there is a common contact with virus B. - There are significant alternations of the cellular and humoral immunity in drug-addicts with acute and chronic hepatitis. - In the "asymptomatic" group the humoral immunity is slightly altered (hyper IgM, circulating immunocomplexes), while normal the cellular response. All these findings are critically evaluated also in respect with the new immunopathological mechanisms of hepatitis B.

Acute Disease↗
PubMed1979

Lymphocyte transformation test with rabbit liver specific lipoprotein (RLSP) in chronic active hepatitis.

Cellular sensitization to rabbit liver specific lipoprotein (RLSP) has been investigated using a lymphocyte transformation test in patients with chronic active hepatitis (CAH). A stimulation index greater than 2 was recorded in twenty out of twenty-five cases (eight of ten HBsAg positive and twelve of fiteen HBsAg negative) while values were lower than 2 in all the normal subjects. These results confirm the finding of sensitization to LSP in chronic active hepatitis irrespective of HBsAg status and show that rabbit LSP can be used as an alternative to the human antigen in the lymphocyte transformation test, and is further evidence that this liver membrane lipoprotein has antigenic determinants which have species-cross-reactivity.

Animals↗
PubMed1977

[Hepatitis A and hepatitis B. Clinical, epidemiological and differential immunological elements].

The Authors have already related in various papers the results of their research on humoral and cellular immunity in the course of viral hepatitis in relation to the behaviour of HBsAg determined with various methods and recently with the radio-immune assay. Since the high sensitivity of this latter technique consents a sufficiently precise differentiation of hepatitis into HBAg-positive (hepatitis B) and HBAg-negative (hepatitis A), the Authors have intended studying in this work the eventual clinical epidemiological and immunological differences between the two types of hepatitis, analyzing the results of their previous studies, extending the case data and gathering numerous other personal observations, clinical and laboratory, not yet published. The study was limited to 136 patients with viral hepatitis in wwhich the test for HBsAg was effected with RIA: of these 58 were HBAg+ and 78 HBAg-. Initially is discussed the incidence of two types of hepatitis in relation to age and sex and then the comparative incidence between them of the various routes of contagion. Particularly emphasized is the possibility of direct transmission of HBAg+ hepatitis, often responsible for infection within the family. The comparative determination of transaminases, bilirubin, immunoglobulins and complement has revealed some interesting variations in the behaviour of the two types of hepatitis. Instead, cellular immunity, studied by the rosette E technique, appeared depressed in the initial phase of sickness in both types of hepatitis. Space is dedicated to the behaviour of HBsAg in acute HBAg+ hepatitis in relation to the immunoglobulins and complement and in relation to the normalization of the transaminases and bilirubinemia. After a few brief observations on the frequent appearance of a joint symptomatology in the course of viral hepatitis, particularly in the HBAg+ form, the Authors report the data relative the evolution of the hepatitis cases examined. The percentage of a complete cure are about equal between hepatitis A and hepatitis B even recovery is significantly faster in the first type of hepatitis (HBAg-).

Adolescent↗
PubMed1975

[Further aspects of combination antibiotic therapy. Critical review and personal case studies].

A brief account of the aims sought by multiple antibiotic management is followed by an assessment of the antagonism and synergism displayed by associations of two bactericidal antibiotics, two bacteriostatic antibiotics, and one bactericidal and one bacteriostatic antibiotic. Instances of synergism between bactericides (particularly penicillins and aminosides) are mentioned. Stress is laid on recent studies on the mechanism of action of antibacterial drugs showing unmistakeable synergism between trimethoprim and sulphamethoxazol and between chloramphenicol and tetracycline. The antagonism between bactericides and bacteriostatics noted by Jawetz et Al. has not been confirmed clinically in a number of reported series. The main indications for combined antiobiotic therapy are reviewed: endocarditis, purulent meningitis, staphylococcia, brucellosis, salmonellosis, shigellosis, other Gram-negative infections and fever in the course of blood diseases. References is made to personal experience in the management of 35 cases of bacterial endocarditis, 15 cases of purulent meningitis and various forms of serious Gram-negative infection. Leaving aside exceptional cases, the clinical effects of antibiotic associations are uncertain and influenced by too many variables. The technique is still of importance, however, despite the introduction of many new antibiotics. It must not be thought of as a handy method for indiscriminate use, however; its indications (which are summarised) are quite clear.

Adult↗