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Biomedical subjects

J Zajac

Publications and source records attributed to J Zajac.

At least 37 records · Page 2Linked to original sources
PubMed1992

[Detection of antibodies to infectious bronchitis of fowl using the ELISA, hemagglutination-inhibition test and agar-gel precipitation test].

Chicks of a conventional poultry flock, Shaver Starcross 288 hybrid, were vaccinated with infectious bronchitis (IB) virus H 120 at the age of 21 days. Three weeks later, the chicks were divided into three groups and separate groups were infected with infectious bronchitis viruses M 41 and D 274 or revaccinated with virus H 120. The content of specific antibodies to antigens prepared from homologous and heterologous viruses of infectious bronchitis used for chick vaccination and infection was investigated at regular intervals in the separate groups of chicks by means of an ELISA technique and haemagglutination-inhibition test (HIT). Serotype specificity of haemagglutination-inhibition test was documented by the results; the specificity was obvious mainly after the first vaccination and two weeks after infection, or after chick revaccination (Fig. 1). The dynamics of postinfective or postvaccinal antibodies, recorded by the ELISA technique, had analogical patterns in the separate groups of chicks, and there were no larger differences in the values determined on the basis of different antigens during the investigation (Fig. 2). A total of 52 group samples of fowl serum was examined by the ELISA technique and agar-gel precipitin test (AGPT) in another part of this study. Ten serums of identical origin represented the separate groups. The result of this examination was evaluated from the percentage of samples with precipitin activity in the group, or from the average value of ELISA. Mutual comparison of the mentioned values indicated that the precipitin activity was limited by the positivity degree of ELISA reaction (Fig. 3).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Wplyw rodzaju bodzća dzẃiekowego na oznaczanie progu slichowego metoda ABR. [The effect of brief tone envelopes on ABR and behavioral thresholds].

The present study examines the effect of brief tone envelopes on ABR and behavioral thresholds in small groups of normal and hearing-impaired subjects. The hearing-impaired subjects had very steep high-frequency hearing loss in 2-6 kHz region. The stimuli for both ABR and behavioural estimates were 2 and 4 kHz tone burst with linear and nonlinear envelopes. Behavioural thresholds were estimated using a computer controlled, modified block up-down method. The ABR thresholds were evaluated from the recordings collected in automatic acquisition process. Results of our experiments showed that for different stimulus envelopes both behavioural and ABR thresholds were similar in normal range of hearing. However, for impaired ears at high frequencies, both psychoacoustic and ABR thresholds differ, sometimes quite significantly, depending on stimulus envelope.

Audiometry, Pure-Tone↗
PubMed1991

A new treatment for acquired reactive perforating collagenosis.

Acquired reactive perforating collagenosis is reported in an insulin dependent diabetic patient with renal impairment, managed successfully with surgical debridement and split skin grafting. The literature on treatment of reactive perforating collagenosis is reviewed.

Adult↗
PubMed1991

[Antibody response in mice, rabbits and pigs in response to vaccination with an inactivated oil vaccine containing rotavirus and Escherichia coli strains with K88, K99 and 987P fimbrial antigens].

In trials with mice, rabbits and weanling piglets, four experimental charges of a combined inactivated oil vaccine against diarrhoeas in mammals were tested: the vaccine was to be implanted to sows and it contained porcine rotavirus (PRV); two charges also contained bovine rotavirus and bacterins of enterotoxicogenic strains of E. coli with protective antigens K88, K99 and 987P. At low starting antibody titres the twofold i.m. implantation of 0.2 ml vaccine stimulated in mice the production of antibodies to reach the average titre value of 1:128 against PRV and of 1:256 against BRV; in rabbits the twofold i.m. implantation of 2 ml vaccine stimulated the antibody development to reach the average titres of 1:508 or 1:500, and in weanlings after the twofold i. m. implantation of the vaccine the titres were 1:1028 or 1:469; in mice agglutination antibodies to antigen K88 had the average value of 1:68, to antigen K99 the value of 1:44 and to antigen 987P the value of 1:8192; in rabbits the respective titres were 1:285, 1:136 and 1:6006 and in pigs 1:570, 1:631 and 1:8192. The antibodies to antigen 987P persisted at the same level in pigs for six months. Even though there was a gradual decrease in the antibodies to antigens K88 and K99, at that time the values were 9.8 times, or 15.2 times higher than the starting values, and only the antibodies to PRV dropped to the pre-vaccination level. Repeated administration of vaccine to pigs after six months from revaccination induced, with the exception of antigen 987P, an increase in antibodies in a fortnight to reach such titres that were recorded after revaccination.

Adhesins, Escherichia coli↗
PubMed1990

Effect of Cd2+ on ATP synthesis coupled to electron transfer in cadmium-resistant and -sensitive Staphylococcus aureus.

In the Cd2(+)-resistant Staphylococcus aureus 17810R which contains the plasmid-coded Cd2+ efflux system, accumulation of Cd2+ was highly reduced. Consequently, neither respiration nor ATP synthesis coupled to electron transfer were inhibited. The plasmidless S. aureus strain 17810S accumulated Cd2+ via the Mn2+ porter down the membrane potential (delta phi) which resulted in inhibition of respiration and of ATP synthesis.

Adenosine Triphosphate↗
PubMed1987

[Evaluation of the results of the ELISA reaction in the serologic diagnosis of bovine leukosis].

Blood serum samples collected from two cattle herds were examined by the immunodiffusion test (ID), pseudotype neutralization test (PsNT) and ELISA procedure for the presence of antibodies to the bovine leukosis virus. The spectrophotometric readings of the ELISA procedure were evaluated on the basis of the arithmetical mean (means) and standard deviation (Sd) of the values obtained in negative controls. The examination of 208 samples of serums taken in the negative herd confirmed in all cases a negative reaction in the ID and PsNT tests. In all samples the ELISA reaction values remained within the range delimited by the relation of means + 3 Sd, which was defined as the threshold value of positive reaction. Out of the 223 serum samples of the positive herd, 132 samples were within the range below means and five of them were leukosis-positive in PsNT. Twenty-nine samples were within the range of means to means + 3 Sd; five of them were found positive in PsNT and three in the ID test. Sixty-two samples were above the threshold value of positivity; of these, positivity was confirmed in 58 cases by PsNT and in 55 cases by ID. As the results suggest, the ELISA procedure is suitable for the detection of animals positively reacting to bovine leukosis, to which special attention should be paid.

Animals↗
PubMed1986

Comparative double-blind trial of the effectiveness and antigenicity of semisynthetic human insulin and purified porcine insulin in newly treated diabetic subjects.

A double-blind comparative trial of the effectiveness and antigenicity of semisynthetic human insulin (Novo) and highly purified (Monocomponent) porcine insulin was performed over a 12 month period in 20 diabetic subjects newly treated with insulin. Human insulin was shown to be indistinguishable from porcine insulin of comparable purity with respect to plasma glucose and glycosylated hemoglobin levels and insulin dose requirements. Human insulin was no less antigenic than porcine insulin; significant IgG-associated insulin binding activity was detected in six of the ten patients in the human insulin treated group and four of the ten patients in the porcine insulin treated group. In all patients, the binding activity was of low capacity. No adverse reactions to human insulin were noted. It is concluded that semisynthetic human insulin, like purified porcine insulin, is safe and effective. Although there may be advantages for human insulin in the setting of insulin allergy, this study does not indicate that human insulin has advantages over purified porcine insulin with respect to elicitation of antibodies of the IgG class.

Adult↗
PubMed1986

[Comparison of the immunizing effectiveness of subunit vaccine and inactivated viral oil vaccine against infectious rhinotracheitis of cattle].

Trials were conducted on rabbits and cattle to compare the immunizing effectiveness of the subunit vaccine against infectious bovine rhinotracheitis (IBR), representing antigens separated by the solubilization of the IBR virus-infected cells by means of Triton X-100 with oil adjuvant, with the inactivated oil IBR vaccine. The rabbits inoculated and re-vaccinated with both vaccines in an interval of three weeks produced neutralizing antibodies in medium titres, the values of these antibodies were balanced in both groups. Cattle immunized with the subunit vaccine reacted to the inoculation and re-vaccination by producing serum antibodies of higher titres, as compared with the cattle inoculated with the virus vaccine; secretory antibodies were detected only after re-vaccination and had balanced values in both test groups. After intranasal infection with the virulent virus performed after 14 days from re-vaccination, the calves inoculated with the subunit and virus vaccines were protected against clinical disease whereas the non-inoculated control calves fell ill with symptoms characteristic of IBR. The immunized animals of both experimental groups had a smaller amount of virus p.i. in nasal secretions and for a shorter time than the control non-inoculated calves. The intensity of multiplication and persistence of infectious virus excretion were the same in both experimental groups.

Animals↗
PubMed1984

Purification and some properties of protamine kinase from rabbit brain.

A protein kinase of high specificity towards protamine and ATP was isolated from rabbit brain and purified about 200-fold. The enzyme does not catalyse phosphorylation of acidic proteins, e.g. casein and phosvitin, nor is it susceptible to cyclic AMP or protein inhibitors of the cAMP-dependent kinase. The enzyme shows the highest activity in the presence of 10 mM-Mg2+ and 2 mM-dithiothreitol at pH 8. The only phosphorylated amino acid found in protamine phosphorylated by the enzyme was phosphoserine.

Adenosine Triphosphate↗