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K R Berquist

Publications and source records attributed to K R Berquist.

48 records · Page 3Linked to original sources
PubMed1971

Sensitive matrix gel diffusion test for the detection of Australia antigen.

A matrix gel diffusion (MGD) procedure with a sensitivity comparable to the complement fixation test (CF) has been developed for detecting Australia antigen in serum. The test utilizes a thin layer of agar (0.1 mm) with an applied plastic matrix. Reactants are introduced directly onto the surface of the agar through wells in the plastic matrix. End points obtained by CF with a panel of 11 sera varied from 1:8 to 1:512. When these sera were tested by MGD, end points for detection of antigen were within one dilution of that obtained by CF.

Agar↗
PubMed1968

Hemagglutinating activity of enteroviruses recovered in two primary cell lines and a stable line.

A microhemagglutination technique was used to detect hemagglutinating properties of enteroviruses recovered in two primary cell lines, monkey kidney (MK) and human amnion (HAm), and in a continuous cell line, human embryonic lung (HEL). During a 3-year period, 1,528 isolations of enteroviruses were tested for hemagglutinating activity and hemagglutination inhibition response; 96.3% of the viruses were also identified by virus neutralization tests. Enteroviruses recovered in HEL were far less likely to develop hemagglutinins than viruses isolated in MK or HAm. Of the enteroviruses known to agglutinate human type O cells, 77.8% of the primary viral isolates from MK, 62.1% of the isolates from HAm, and 20.3% of the isolates from HEL exhibited this property. An additional 8.1% of the isolations obtained in HEL hemagglutinated human cells after a single passage in MK. The microhemagglutination technique using microtiter equipment was simple to perform, saved time and valuable typing sera, and helped to obtain identifications rapidly.

Child↗
PubMedDate not supplied

Viral hepatitis, type B, in experimental animals.

Evidence of natural infection with hepatitis B virus (HBV) in chimpanzees was followed by demonstration that this species provides a highly sensitive animal model system for experimental type B hepatitis. With rare exceptions, inoculation of sero-negative chimps with materials containing infectious HBV produces serologic evidence of infection including appearance of circulating hepatitis B surface antigen (HBs Ag) and subsequently development of antibody to HBs Ag and hepatitis B core antigen. Serum enzyme elevations indicative of liver damage occurred in 31 of 46 aminals infected to date. The antigenic subtypes of HBV in the inocula breed true in the infected animals, and HBV titers of sera containing the adw and ayw subtypes have been established as 10(7.5) infectious units/ml. Rhesus monkeys also provide a valuable animal model for type B hepatitis, but they appear to be less sensitive than chimps, and they do not develop evidence of liver damage.

Animals↗
PubMedDate not supplied

Immunofluorescent localization of hepatitis B antigens in chimpanzee tissues.

Three chimpanzee chronic carriers of hepatitis B surface antigen (HBs Ag) were examined by immunofluorescent techniques to determine the localization of HBs Ag and hepatitis B core antigen (HBc Ag) in their tissues. All specimens were quick-frozen in liquid nitrogen and stored at -70degrees until sectioned. Frozen sections were prepared and stained for examination by fluorescent microscopy. For staining, anti-HBs and anti-HBc labeled with fluorescein isothiocyanate were used. HBs Ag was found in the liver of all three animals. In two animals which were necropsied, HBs Ag was detected in other tissues, e.g., lymph nodes, spleen, and kidney. Specificity of these tests was demonstrated by blocking with purified HBs Ag. Examination of various tissues revealed HBc Ag only in the liver. 32 samples of liver, from different sites from one chimpanzee, were examined and all were positive for both HBs Ag and HBc Ag. The finding of HBc Ag only in the liver further supports the assertion that the liver is the sole site of replication of hepatitis B virus in chronic carriers.

Adrenal Glands↗