A novel variant of human interferon alpha 1 gene

A 520-base pair human IFN-alpha gene was isolated by PCR method twice from chromosome DNA of a Chinese (Han Nationality) fetal liver. The nucleotide sequences were determined. These two separately amplified DNA fragments shared the completely identical nucleotide sequence but possessed C and G at positions 410 and 541, respectively, which differ from those of IFN-alpha 1 and IFN-alpha D previously described. Therefore the deduced amino acid sequence would have an Ala at position 114 and a Val at position 158. At all other sites it has the same amino acids as those in IFN-alpha 1 and IFN-alpha D. We recommend that IFN-alpha D gene, IFN-alpha I gene and IFN-alpha I/158V gene found in our laboratory, be named IFN-alpha 1a gene, IFN-alpha 1b gene and IFN-alpha 1c gene.

Lack of effects of selenium on N-nitrosomethylbenzylamine-induced tumorigenesis, DNA methylation, and oncogene expression in rats and mice

The effects of dietary selenium deficiency and excess on N-nitrosomethylbenzylamine-(NMBA) induced esophageal neoplasia in rats and forestomach tumors in mice and the effects of dietary selenium on DNA adduct formation and on the activities of DNA adduct-repairing enzyme and oncogene expression in rat esophagus were investigated. The esophageal and forestomach tumors were induced by administration of NMBA by gavage with a total dose of 39 mg/kg body wt in rats and 12 mg/kg body wt in mice. Neither selenium dietary deficiency (Se < 0.02 ppm) nor selenium excess (2.0 ppm) showed any significant effect on the incidence of tumors or number of tumors per tumor-bearing animal. For the DNA adduct formation studies, rats were given a dose of NMBA intraperitoneally after six weeks on the different selenium-containing diets. No significant difference in the amount of the DNA adduct O6-methyldeoxyguanosine was found among the different selenium-treated groups. In a parallel group of rats that did not receive NMBA, the levels of esophageal O6-methyldeoxyguanosine DNA methyltransferase were not significantly altered by dietary selenium levels. The c-myc oncogene expression in rat esophagus was induced by the administration of NMBA (3 mg/kg body wt) by gavage once a week for eight weeks. Dietary selenium did not show any effects on its expression. On the basis of the results of these studies, dietary selenium has no effects in the NMBA-induced tumor model.

Preliminary study of quantification of regurgitant volume in mitral regurgitation by color Doppler echocardiography

A method for quantification of regurgitant volume in mitral regurgitation (MR) was studied. 31 cases of MR were investigated with color Doppler. The reliability of measuring velocity by Doppler and the influence of pressure gradient on MR were assessed and confirmed by experimental device. The results suggested that the best method in quantification of the regurgitant volume was "calibrating method" (r = 0.99; P less than 0.01), the next to the best was "volume method" (r = 0.74; P less than 0.01), whereas the regurgitant volume evaluated by multiplication of area, velocity and time was far from the actual regurgitant volume (r = 0.47; P greater than 0.05). The velocity of blood flow measured by Doppler is closely correlated to results obtained from experiments (r = 0.69; P less than 0.05). We believe that the ratio of back flow area and average area of left atrium calculated by Helmcke's method reflects the severity of the disease to a certain degree, bu there are many problems unsolved, e.g. the determination of the velocity of blood flow by color Doppler is dependent on the degree of brightness of coloration; the brighter the color, the quicker the speed it represents, whereas the darker coloration speaks for slower speed.

[Electron microscopic observation of the effects of Rhodiola kirilowii (Regel.) Maxim. in preventing damage of the rat viscera by a hypoxic high altitude environment]

This paper has shown that the pathologic damages done to rat's viscera due to hypoxic environment of altitude can be reduced significantly by oral administrations of Shengmaiyin, Danshen-Chuanxiong mixture and Rhodiola kirilowii. Shengmaiyin that maintains interior substances in the plate layer bodies proves more effective than Danshen-Chuanxiong mixture, while the latter excels in preventing capillary contraction, thus improving blood circulation. Rhodiola kirilowii has the effects of both Shengmaiyin and Danshen-Chuanxiong mixtures.

RFLP for human DBH (dopamine beta-hydroxylase)

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Observation of high-order degenerate wave mixing in BaTiO(3)

We report for the first time to our knowledge some phenomena of high-order degenerate wave mixing observed in a BaTiO(3) crystal when self-pumped phase conjugation occurs. Applications of these phenomena are discussed.

Estrogen influences dolichyl phosphate distribution among glycolipid pools in mouse uteri

The steroid hormone 17 beta-estradiol dramatically induces uterine N-linked glycoprotein assembly [Dutt, A., Tang, J.-P., Welply, J. K., & Carson, D. D. (1986) Endocrinology (Baltimore) 118, 661-673]. To determine the role that dolichyl phosphate availability plays in this induction, we studied the effects of estrogen priming on the content of dolichyl phosphate and the distribution of dolichyl phosphate among various glycolipids in uteri. Dolichol-linked saccharides were metabolically labeled to equilibrium with either [3H]glucosamine or [3H]mannose and extracted from primary explants of uterine tissue. The amount of dolichol-linked saccharide was calculated from the specific radioactivity determined for the corresponding sugar nucleotides extracted from the tissues. The major dolichol-linked saccharides identified were mannosylphosphoryldolichol (MPD), oligosaccharylpyrophosphoryldolichol (OSL), and N,N'-diacetylchitobiosylpyrophosphoryldolichol (CBL). Estrogen increased the levels of MPD and OSL 4-fold; however, CBL levels did not change. After 3 days of treatment, the levels of these glycolipids were very similar to those in uteri from pregnant mice. Remarkably, MPD constituted 90-95% of dolichol-linked saccharides detected under all conditions. The tissue contents of total dolichyl phosphate and alkali-labile dolichyl phosphate, presumably MPD, were estimated by liquid chromatography. The levels of alkali-labile dolichyl phosphate determined in this way were in good agreement with the values estimated for MPD by metabolic labeling; moreover, alkali-labile dolichyl phosphate constituted 50-98% of the total dolichyl phosphate pool. The variations in MPD content depended upon the steroid hormone influence, most notably that of estrogen.(ABSTRACT TRUNCATED AT 250 WORDS)

Resistance to trimethoprim and other antibiotics in shigellae isolated in the province of Ontario

Antimicrobial susceptibility determinations for three commonly used and seven seldom used antibacterial drugs against 482 strains of shigellae isolated in Ontario during 1977 and 1978 were carried out. Resistance to the first-line treatment drugs, ampicillin and tetracycline, occurred in 20.5 and 39.2% of strains, respectively. The emergence of trimethoprim-sulfamethoxazole resistance was noted for the first time in 3.2% of the strains in 1978. All strains retained their susceptibility to gentamicin, nalidixic acid, and polymyxin but were variably susceptible to chloramphenicol, cephalexin, and rifampin.