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Biomedical subjects

A Mayr

Publications and source records attributed to A Mayr.

At least 181 records · Page 10Linked to original sources
PubMed1976

Oral immunization against pox. Studies on fowl pox as a model.

Oral vaccination against fowl pox is both effective and harmless. A suitable vaccine strain is the attenuated HP-1 strain in the 200th to 400th tissue culture passage. For optimal immunization virus of the 200th to 270th passage level should be applied twice at an interval of 3 to 4 weeks. Vaccination dose should contain 10(7.0)TCID50. Chickens may be effectively immunized already at 5 days. Immunity is against both homologous and heterologous virus and proves equally resistant to oral, cutaneous and intravenous challenge. Protection of mucous membranes of the upper respiratory and digestive tract forms faster than after cutaneous immunization. Compared to conventional fowl pox vaccination, drinking water vaccination facilitates the technicalities of vaccination; there are immunological advantages and risks of complications are avoided. It can therefore be recommended as a model for vaccination against smallpox in man.

Administration, Oral↗
PubMed1975

Sporadic bovine meningo-encephalitis-isolation of a paramyxovirus.

Isolation of a viral agent (107) directly from brain explants of a 15-month-old heifer with symptoms of a sporadic encephalomyelitis is described. The virus shares properties with the paramyxovirus family. It grows in a variety of cell cultures from different species, and induces nuclear and cytoplasmic inclusion bodies in infected cells. Nucleocapsids measuring 17 nm in diameter were found in the nucleus and cytoplasm of these cells when studied electron microscopically, thus indicating a close relationship of the agent to the measles-distemper-rinderpest group. No infectious virus was released from infected cells, although alignment of nucleocapsids was observed beneath the cell membrane, and no hemagglutinating activity could be detected with the methods employed. The 107 agent was compared serologically with parainfluenza viruses type 1, 2 and 3, simian virus 5, mumps and Newcastle disease virus (NDV), two bovine respiratory syncytial viruses and measles/subacute sclerosing panencephalitis, distemper and rinderpest viruses, always using 107 virus infected CV1 cells and antiserum of the different viruses in indirect FA tests. Positive FA reactions were observed only with two sera obtained from SSPE patients with high antibody titer to SSPE virus, and with one rabbit-anti-rinderpest serum. The titers of these sera to 107 virus, however, were significantly lower than those against homologous viruses. Five out of 9 sera from randomly selected healthy cattle showed antibody titers between 1:10 and 1:80 to 107 virus in FA tests. The significance of these results is discussed with respect to the epidemiology of SSPE in children and its possible implication with rinderpest in Europe.

Animals↗
PubMed1975

[Experimental investigations on oral immunization with tetanus-toxoid (author's transl)].

Model-experiments in mice were used for the investigation of oral immunization with tetanus-toxoid. The efficacy of oral toxoid application was tested by challenge and anti-toxin determination. The oral immunization with tetanus-toxoid induced only a sufficient protection, when toxoid was in intensive contact with the mucous membranes of the oral cavity. Local immunization via gastro-intestinal-tract failed. After a single vaccination with 200 Lf tetanus-toxoid onto mucous membranes of the oral cavity the efficiency index was 75. In comparison, a single subcutaneous application of 2 Lf tetanus-toxoid resulted in an efficiency index of 100 and a single intranasal immunization of 100 Lf in an efficiency index of 93. So the application of toxoid subcutaneously or onto nasal mucous membranes induced higher protection than oral application. Temporary development of immunity after immunization via the mucous membranes of the oral cavity was much better than parenteral immunization. 20 per cent of orally immunized animals were immune 5 days p. vacc. At the same time subcutaneously immunized animals failed to develop any protection. The efficiency rates obtained in challenge correlate with antitoxin content in the serum.

Administration, Oral↗