Biomedical subjects

G C Simmons

Publications and source records attributed to G C Simmons.

At least 19 recordsLinked to original sources

PubMed1983

The association of hepatitis B viral infection and hepatocellular carcinoma in New Zealand.

Eighty-eight patients presented to the Auckland hospitals with proven hepatocellular carcinoma between 1970 and 1981. The clinicopathological characteristics were analysed according to the racial and ethnic background of the patients. The cancer incidence for Auckland resident Polynesians (Pacific Islanders) was 5.8/100 000/year, that for the native Maori was 2.8/100 000/year and for the European was 0.6/100 000/year. The mean age in presentation of the hepatocellular carcinoma was 44, 49 and 63 years for Pacific Islanders, Maori and Europeans respectively. In general (non-tumorous) population, the hepatitis B surface antigen (HBSAg) carrier rate was 7.0% for the Pacific Islander and Maori and 0.5% for the Europeans. In the tumour patients where HBSAg were tested, 66% of Pacific Islanders, 100% of Maori and 0% of Europeans had positive antigenaemia. Histological sections were studied by orcein staining. Positive staining for viral particles were found mainly (80%) in hepatocytes of Pacific Island and/or Maori patients. These data indicated that within the same area, Pacific Islanders and Maori had a higher HBSAg carrier rate, higher incidence of hepatocellular carcinoma and presented at a younger age, and in the tumour-bearing patients had a higher incidence of HBSAg antigenaemia as well as viral particles in their liver.

Carcinoma, Hepatocellular↗

PubMed1980

Immunoglobulin classes in serum antibody reactions in cattle following vaccination with Brucella abortus strain 19 and killed 45/20 vaccines.

A group of 4 cows was vaccinated with Brucella abortus strain 19, followed 8 weeks later by a single dose of B. abortus 45/20 vaccine. A similar group received 2 doses of B. abortus 45/20 vaccine 8 weeks apart. The antibody responses of the groups were compared by testing whole serums and separated IgM and IgG fractions by the Rose Bengal Plate (RBP) agglutination and the complement fixation tests (CFT) using rough and smooth B. abortus antigens. Animals that had received B. abortus strain 19 responded to the 45/20 vaccine with increased titres to the smooth antigen. These relevant antibodies were predominantly of the IgG class. Standard CFT and RBP test antibodies could be detected in IgM and IgG fractions after the primary inoculation with B. abortus strain 19 vaccine.

Animals↗

PubMed1978

Factors in the spread of salmonellas in meatworks with special reference to contamination of knives.

Immersion of knives momentarily in hot water (82 degrees C) was ineffective in destroying salmonellas on knives used in a meatworks to carry out the bung dropping operation. Laboratory experiments confirmed that knives covered with meat products required 10 or more seconds to be effectively decontaminated at this temperature. Examination of knives used for slaughtering and for dressing beef carcases showed that knives coming into contact with hides had higher counts for salmonella and a higher percentage positive than knives used for other cutting operations. Knives used for cutting the skin of the forelegs and hindlegs had the highest counts.

Animals↗

PubMed1976

The effect of dazomet on salmonellas on artificially contaminated eggs.

Salmonellas were isolated from the surface of only 1 of 21 artificially contaminated eggs after they had been treated with dazomet. By comparison salmonellas were isolated from the surface of 13 of the 21 untreated eggs. Penetration by the salmonellas through the shells to the shell membranes resulted from the immersion of warm eggs in a cold suspension of salmonella cells. While the dazomet treatment reduced the incidence of salmonellas within the shells and shell membranes, elimination of salmonellas from all eggs was not achieved. However, the numbers of surviving salmonellas on the eggs were small; a count of 4 per shell being recorded compared to greater than 110,000 per shell of the untreated eggs. The failure to achieve complete elimination of salmonellas within the shell and membranes appeared to be due to inadequate penetration of the fumigant to these structures.

Animals↗

PubMed1975

A study of the number and phage patterns of Staphylococcus aureus in an abattoir.

Two hundred and forty-seven samples were taken from various areas within an abattoir and the levels of Staphylococcus aureus determined. Sixty-one phage patterns were found in the 141 samples containing coagulase-positive staphylococci. The incidence of coagulase positive staphylococci increased as processing progressed. Articles such as mesh gloves, hands and aprons which were either difficult to effectively clean or maintained at elevated temperatures harboured the greatest numbers of staphylococci. Over 50% of the positive samples contained multiple phage patterns of staphylococci.

Abattoirs↗

PubMed1975

The use of fluff counts in a study of hygiene in Queensland hatcheries.

During 1972, 333 fluff samples were tested from 13 Queensland hatcheries and assessed according to the English standards for total count, coliforms and fungi. They were also assessed as being "standard" or "substandard", using a combination of the criteria of the English system. All hatcheries had at least 2 substandard samples and all the samples from 2 hatcheries were substandard.

Animals↗

PubMed1973