Immunoglobulin level in viral hepatitis patients]

The results of studying the dynamics of serum immunoglobulins in patients with viral hepatitis varying in severity are presented. At the acute stage of the disease pronounced shifts in the content of all the three classes of immunoglobulins were found to occur in the patients irrespective of their age. Higher levels of IgM detected in women seem to be due to the physiological peculiarities of the female organism. Gamma globulin prophylaxis, when carried out at the incubation period, has been shown to exert a negative influence on humoral immunity.     

Detection of Epstein-Barr viral antibodies in patients with acute viral hepatitis

Serum samples obtained from 44 patients with virus A hepatitis, 23 patients with virus B hepatitis, 65 patients with virus non A, non B hepatitis and 100 healthy adults were studied for the presence of Epstein-Barr (EB) virus in the indirect immunofluorescence test. In this work lymphoblastoid cell lines PH3-J-1 and CN37 were used. Among patients with different forms of hepatitis, the statistically significant elevation of the titers of antibodies to EB virus was detected only in the group of patients with virus non A, non B hepatitis, and in 6 cases the etiological role of EB virus was confirmed by serological and hematological methods.     

Serologic studies in viral hepatitis]

Comparative studies of sera from 710 patients with viral hepatitis and contacts were made during the 1958-1973 period for hepatitis antigens (Au antigen and the Botevgrad antigen). The percentage of virus hepatitis in patients positive for the Au and the Botevgrad antigens varied in different years. The percentage of those positive for the Au antigen ranged from 50 in 1958 to 8.8 in 1970-1971, while for the Botevgrad antigen--it ranged from 32.6 in 1962-1963 to 6.1 in 1966. In case of contacts, mostly in the 7-14 age group the sera positive for the Au antigen were found in a low percentage (2.09 percent) of cases; as to the Botevgrad antigen, 20 persons were found positive during various epidemics (55 percent). Simultaneous presence of both antigens was found in 4 of the 710 patients with virus hepatitis (0.56 percent), and in 2 of 431 contacts (0.46 percent).     

Role of epithelial nitric oxide in airway viral infection

The airway mucosal epithelium is the first site of virus contact with the host, and the main site of infection and inflammation. Nitric oxide (NO) produced by the airway epithelium is vital to antiviral inflammatory and immune defense in the lung. Multiple mechanisms function coordinately to support high-level basal NO synthesis in healthy airway epithelium and further induction of NO synthesis in the infected airway of normal hosts. Hosts deficient in NO synthesis, such as those patients with cystic fibrosis, have impaired antiviral defense and may benefit from therapies to augment NO levels in the airways.     

Reactive oxygen species and nitric oxide in viral diseases

Metabolites derived from superoxide (o₂ ^??) and nitric oxide (NO?) play an important role in antimicrobial and antitumoral defense, but may also harm the host. Low levels of such metabolites can also facilitate viral replication because of their mitogenic effects on cells. Most viruses grow better in proliferating cells, and indeed, many viruses induced in their host cell changes similar to those seen early after treatment with mitogenic lectins. Influenza and paramyxoviruses activate in phagocytes the generation of superoxide by a mechanism involving the interaction between the viral surface glycoproteins and the phagocyte’s plasma membrane. Interestingly, viruses that activate this host defense mechanism are toxic when injected in the bloodstream of animals. Mice infected with influenza virus undergo oxidative stress. In addition, a wide array of cytokines are formed in the lung, contributing to the systemic effects of influenza. Oxidative stress is seen also in chronic viral infections, such as AIDS and viral hepatitis. Oxidant production in viral hepatitis may contribute to the emergence of hepatocellular carcinoma, a tumor seen in patients after years of chronic inflammation of the liver. Antioxidants and agents that downregulate proinflammatory cytokines and lipid mediators may be a useful complement to specific antiviral drugs in the therapy of viral diseases.     

The epidemiological differential diagnostic signs of viral hepatitis A and viral hepatitis E]

A retrospective epidemiologic analysis of cases diagnosed as hepatitis A (HA) has been made in territories characterized by high intensity (4 towns in Central Asia) and low intensity (Novomoskovsk, Tula Province) of the epidemic process development. Morbidity structures for different age and social groups of the population, as well as the morbidity time course, both annual and over many years, were analyzed over 1973-1986. Specific features in the development of the epidemic process in HA and hepatitis E (HE), formerly called hepatitis non-A, non-B with the fecal/oral mechanism of the infection transmission, were studied. Twelve epidemiological differential diagnostic signs of these two infections were formulated, classified, and validated. Contribution of centralized water supply and sewage systems to the development of HE epidemic process and the regulating role of infectious immunological mechanisms in the development of HA epidemic process were demonstrated.     

Synthesis of nitric oxide in the bovine retina.

In the absence of light, high concentrations of cGMP open ion channels in the plasma membranes of rod outer segments. The source of stimulation of retinal guanylate cyclase is not known. Nitric oxide is a potent stimulator of guanylate cyclase in other cell systems. The present data demonstrate that nitric oxide synthase, an enzyme responsible for the production of nitric oxide, is present in retina, and specifically in the rod outer segments. This enzyme uses L-arginine as a substrate and is NADPH- and calcium- dependent. L-arginine-derived nitric oxide may be a source of activation of guanylate cyclase in the retina.