Independent mitochondrial origin and historical genetic differentiation in North Eastern Asian cattle.

In order to clarify the origin and genetic diversity of cattle in North Eastern Asia, this study examined mitochondrial displacement loop sequence variation and frequencies of Bos taurus and Bos indicus Y chromosome haplotypes in Japanese, Mongolian, and Korean native cattle. In mitochondrial analyses, 20% of Mongolian cattle carried B. indicus mitochondrial haplotypes, but Japanese and Korean cattle carried only B. taurus haplotypes. In contrast, all samples revealed B. taurus Y chromosome haplotypes. This may be due to the import of zebu and other cattle during the Mongol Empire era with subsequent crossing with native taurine cattle. B. taurus mtDNA sequences fall into several geographically distributed haplogroups and one of these, termed here T4, is described in each of the test samples, but has not been observed in Near Eastern, European or African cattle. This may have been locally domesticated from an East Eurasian strain of Bos primigenius.

An experimental study of the combined effect of radiotherapy and chemotherapy on head and neck squamous cell carcinoma cell line.

OBJECTIVE: We have reported clinical effects of radiotherapy combined with either CDDP or CBDCA for head and neck cancer. In this study, we examined the combined effects of either CDDP or CBDCA with irradiation on the cell lines established from tongue SCC. METHODS: The effects of irradiation, chemotherapy and the combined therapy on growth of the cell lines were examined respectively by the Alamar Blue assay. RESULTS: The combination of 0.1 and 0.25 microg/ml CDDP with four times exposure to I Gy 60Co. which did not affect the growth of the cell lines, suppressed the growth synergistically. The combination of 1.0 and 2.0 ) microg/ml of CBDCA with four times exposure to 1 Gy 60Co showed synergistically suppressive effects on the growth of the cell lines. CONCLUSION: It was suggested that the radiotherapy combined with the platium coordination complexes had a clinical usefulness in patients with head and neck cancer.

Microsurgical techniques in the genetic engineering of Mammalian embryos at the preimplantation stage.

The genetic engineering of mammalian whole embryos has become one of the most popular and fruitful techniques in modern developmental biology, not only to investigate the normal development and pathogenesis of diseases but also to develop future gene-therapy applications for human genetic diseases. Although the rapid advancement of molecular biological techniques has created a theoretical basis for genetically engineering mammalian embryos, it has become practical only after the establishment of the culture system for mammalian embryos, which normally develop (hidden from the human eye) in the oviduct and the uterus, the improvement of optic instruments, and finally, the development and establishment of microsurgical techniques.