There was a 2- to 7-fold increase in nicotinamide methyltransferase activity in the livers of mice and rats bearing seven different kinds of tumors compared with the respective control normal livers, ...while activity in the tumors themselves was hardly detectable. The activity in the liver started to increase markedly 3-7 days after i.p. transplantation of Ehrlich ascites tumors into the mice, maintaining a plateau up to death. Metabolic conversion of 14C-nicotinamide to 14C-N1-methylnicotinamide was 3-fold higher in the slices of the ascites tumor host liver than in the normal liver, but the conversion to other radioactive metabolites was not significantly different. Nicotinamide methyltransferase was finally purified 20,000-fold with a yield of 4% from the cytosolic fraction of the ascites tumor host liver by means of five purification steps. At every purification step, only one enzyme fraction was detected. The enzyme finally isolated exhibited a single protein band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, with a molecular weight of 26,000. As for the compounds investigated, including the substrates for methyltransferases other than nicotinamide methyltransferase, only quinoline could be the substrate for enzyme activity. It is suggested that the increase in enzyme activity in the tumor host liver probably derived from the endogenous enzyme preexisting in the liver before tumor transplantation.
To increase the BMS (Beef Marbling Standard) score of Japanese Black Cattle, keeping the cattle serum vitamin A at a low level (30-40 IU/dl) during fattening age is an effective way. The traditional ...method of monitoring the serum vitamin A level is blood assay. However, it is costly, time-consuming and makes cattle stressful. A new approach by using 2CCD camera is proposed in this study. Pupil reflex of cattle with different vitamin A level was analyzed by image processing.
Farmers usually control cattle's serum vitamin A level to improve beef meat fat quality. They sometimes conduct blood tests, but that is invasive and another measurement system is desirable. The ...objective of this study was to investigate the relationship between serum vitamin A level and pupil colors of beef cattle for developing a vitamin A monitoring system by machine vision. Images of cattle eyes were collected and chromaticity values of pupil color were calculated. Although the values had variability, it was found that serum vitamin A had a negative correlation with red component, while it had a positive correlation with blue component.
In order to make better beef with high marbling score, breeders need to control serum vitamin A level from 30 IU/dl to 50 IU/dl during the middle fatting phase. Today, serum vitamin A level of beef ...cattle is usually measured by blood assay. However, blood assay has some disadvantages such as it is cost and time-consuming. For establishment of new method for prediction of serum vitamin A level, this study examined the relationship between serum vitamin A level of Japanese black cattle and the light reflection on pupil. Light reflection measurement was carried out by image processing. This study showed that B in RGB components around halation area on cattle's pupil of color images has possibility of correlation with serum vitamin A level.
