Seizaburo Sakamoto

Association of HLA class II alleles with preference and intake of dairy milk

Abstract The study investigated the possible association between HLA allele frequency and the preference and intake of dairy milk. Ninety-nine Japanese subjects (72 male, 27 female), aged 18–29 years (mean 20.4 years), provided their preference and intake of cow’s milk, by answering ‘like’ or ‘dislike’, and ‘often or daily’ or ‘seldom or never’. Their HLA class II genes (DRB1, DQA1 and DQB1) were analyzed by the polymerase chain reaction sequence specific oligonucleotide probes method. Among the 99 subjects, 37 answered ‘like’ and 62 answered ‘dislike’. For milk intake frequency, 56 of subjects answered ‘often or daily’ and 43 answered ‘seldom or never’. The frequency of HLA-DQA1∗0102 was significantly increased in the ‘dislike’ group for milk preference. The results of the present study suggest that the preference for cow’s milk is negatively associated with the frequency of HLA-DQA1∗0102.

Measurement of Halitosis with a Zinc Oxide Thin Film Semiconductor Sensor

Halitosis, defined as unpleasant oral odor, is a health concern among the general public. Halitosis has been conventionally diagnosed by organoleptic examination and by gas chromatographic analysis of the main source of halitosis, i.e., volatile sulfur compounds, such as H2S and CH3SH. Since gas chromatography requires a large-scale system and a long running time, we investigated the use of a zinc oxide thin film semiconductor sensor for measuring trace volatile sulfur compounds in mouth air. Mouth air samples collected in Teflon bags from 7 patients and 22 volunteers were analyzed by the three methods. The readings of the sensor were correlated with the values of the volatiles measured by gas chromatography (r = 0.712, P < 0.01), and also with the organoleptic scores given by three judges (r = 0.714, P < 0.01). The organoleptic scores were correlated with the gas chromatographic values (r = 0.703, P < 0.01).