No abstract

A temperature sensitive (ts) vaccine strain designated ts-11 was selected after exposure of a low passage culture of the immunogenic Australian field isolate (strain 80083) of Mycoplasma gallisepticum to 100 mg/ml of N-methyl-N-nitro-N-nitrosoguanidine. Viable counts (assayed as colour changing units (CCU)/25 microliters) of a thawed stock culture of ts-11 were typically log10 3 to log10 5 higher when incubated at 33 degrees C (the permissive temperature) than duplicate viable counts incubated at 39.5 degrees C (the restrictive temperature). Doses of approximately 2 x 10(7) CCU of ts-11 caused no gross lesions or loss of egg production when inoculated into the air sacs of susceptible chickens and no clinical or pathological signs of sinusitis when inoculated into the infraorbital sinuses of susceptible turkey poults, whereas the parent strain 80083 was demonstrably pathogenic. However, 1 of 10 poults inoculated intra-abdominally with approximately 2 x 10(7) CCU of ts-11 did show signs of mild airsacculitis. Eight-week-old pullets were vaccinated by eye drop with up to 1.4 x 10(7) CCU of ts-11 and simultaneously subjected to several stressful management practices, without apparent ill effects. Administration by coarse aerosol of 5 ml of ts-11 vaccine/25 day-old broilers, with or without 25 doses of infectious bronchitis virus vaccine caused no obvious signs of respiratory disease. The non virulent ts phenotype was maintained after 3 passages of strain ts-11 in chickens. Chickens vaccinated 3 weeks previously with ts-11 or with strain 80083 were placed in contact with susceptible chickens for a period of 2 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

The gastric cancer incidence in Semarang, Indonesia, is exceedingly low: only approximately 1/100th of the level in Japan. To elucidate the reason, we carried out an ecological study recruiting 69 male and 102 female participants from the general populace in January 2005. Positive urea breath tests were 0% for both men and women, and Helicobacter pylori (H. pylori) IgG antibodies were found in 2% (0-5, 95% confidence interval) of men and 2% (0 -4) of women, significantly lower than the 62% (58-65) and 57% (53-60), respectively, in Japan. Furthermore, there were no positive findings with the pepsinogen tests in Semarang, again significant in comparison with the 23% (22-25) and 22% (20-23) in Japan. Variation in smoking levels and consumption of NaCl, vegetables and fruit were found, but not to an extent that would allow explanation of the major differences in gastric cancer incidence. We may conclude that the very low prevalence of H. pylori infection and thus chronic atrophic gastritis account for the rarity of stomach cancer in Semarang, Indonesia. (Cancer Sci 2005; 96: 873-875) S ince 2002, we have been conducting a collaborative epidemiologic appraisal of host and environmental factors for stomach and colorectal cancer in several South-east Asian countries. Ecological and case-control studies are now being carried out in Hanoi and Ho Chi Minh City, Vietnam; Khon Kaen, Thailand; and Yogyakarta and Semarang, Indonesia, in order to take advantage of the major variation in cancer incidence among these geographical areas and also with data for Japan. Stomach cancer incidence rates in Hanoi, Ho Chi Minh City, Khon Kaen, Yogyakarta and Semarang are approximately 1/2, 1/4, 1/10, 1/50 and 1/100 those prevailing in Japan, respectively: the annual age-adjusted incidence rates for Semarang were 0.6/10 5 for men and 0.3/10 5 for women during 1990-1999, and the respective figures for Japan in 1995 were 67/10 5 and 27/10 5 .(1,2)Gastric cancer may be caused by environmental or lifestyle risks, host genetic polymorphisms, as well as aging.(3) Many laboratory studies have pointed to roles for carcinogenic substances, including amine pyrolysate products and nitrosamines; however, grilled or barbecued meat and fish are categorized as possible risk factors in humans.(3) A probable risk factor for stomach cancer is salt or salty foods, which act synergistically with Helicobacter pylori (H. Pylori) infection in the development of stomach cancer in experimental animals (4) and humans. (5) Convincing preventive factors are vegetables and fruit and refrigeration, and a probable preventive factor is vitamin C. The International Agency for Research on Cancer (IARC) has concluded that gastric cancer is a smokerelated malignancy.(6) H. pylori is a definite carcinogen, (7)(8)(9) and is accepted to be a major factor for chronic atrophic gastritis (CAG), (5) a precursor lesion for stomach cancer.We here report the results of an ecological study of stomach cancer with reference to H. pylori infection and pepsinogen tests as a marker of CAG, ...

No abstract

The immunogenicity of the ts-11 vaccine strain of Mycoplasma gallisepticum was assessed following eye drop or coarse aerosol administration in chickens of various ages. Protection was evalualted following intra-abdominal (IA) or fine droplet aerosol administration of virulent M. gallisepticum, usually the Ap3AS strain and was measured mainly by the scoring of gross air sac lesions or by egg production. Vaccination of chickens with ts-11 did not elicit a substantial serum antibody response as measured by rapid serum agglutination test, or ELISA. Protection was never demonstrated when no M. gallisepticum serum antibody response was detected in a vaccinated group of chickens. Failure to protect occurred usually, although not invariably, following aerosol administration of the vaccine. Vaccination by eye drop usually, although not invariably provided protection against challenge. In one experiment, chickens vaccinated by eye drop at 8-weeks were as susceptible as non vaccinated controls when challenged by IA inoculation at 13-weeks-of-age. Yet other birds from the same vaccinated group were resistant when challenged in an identical way at 23-weeks. No measurable increase in M. gallisepticum specific serum antibody concentrations occurred in the intervening period. Equally surprising was the response of another group of birds in the same experiment that had been vaccinated with a higher dose of ts-11. An antibody response was detected in this group, but they were susceptible to challenge at 23-weeks. Interestingly, a drop in egg production commenced 4 weeks after challenge, 2 weeks later than that observed in a non vaccinated group challenged at the same time.(ABSTRACT TRUNCATED AT 250 WORDS)