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Genomic properties of 62 field isolates of bovine viral diarrhea virus (BVDV) collected from 1974 to 1999 in Japan were investigated. The 5′ untranslated region (UTR) was amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) and the 244 to 247 base nucleotide sequences were determined. Serological properties were also characterized by the cross-neutralization test using antisera against the representative strain of the classified genotype. Using phylogenetic tree analysis, BVDV 1 was subdivided into two major clusters, BVDV-1a (29 isolates) and BVDV-1b (27 isolates). In group 1a, 3 differed from the other viruses, and were classified in a branch assigned as 1a′. However, 4 isolates (So CP/75, 190 CP, 190 NCP and KS86-1-NCP) could not be assigned to group 1a or 1b. In comparison with the published sequence data, KS86-1-NCP, 190 CP and 190 NCP were similar to the Southern Africa isolates that have recently been proposed as BVDV 1c. The 5′ UTR sequence of So CP/75 was unique among those of BVDV 1, suggesting that the isolate should be classified into a new genotype. Only 2 out of 62 isolates collected in 1989 and 1990 were identified as BVDV 2. The results of the cross-neutralization test strongly supported these data, suggesting a close correlation between the 5′ UTR sequence and the antigenicity of BVDV.

The relative contribution of voltage-sensitive Ca 2+ channels, Ca 2+ -ATPases, and Ca 2+ release from intracellular stores to spontaneous oscillations in cytosolic free Ca 2+ concentration ([Ca 2+ ] i ) observed in secretory cells is not well characterized owing to a lack of specific inhibitors for a novel thapsigargin (Tg)-insensitive Ca 2+ -ATPase expressed in these cells. We show that spontaneous [Ca 2+ ] i oscillations in GH 3 cells were unaffected by Ca 2+ depletion in inositol-1,4,5-trisphosphate (IP 3 )-sensitive Ca 2+ stores by the treatment of Tg, but could be initiated by application of caffeine. Moreover, we demonstrate for the first time that these spontaneous [Ca 2+ ] i oscillations were highly temperature dependent. Decreasing the temperature from 22 to 17°C resulted in an increase in the frequency, a reduction in the amplitude, and large inhibition of [Ca 2+ ] i oscillations. Furthermore, the rate of ATP-dependent 45 Ca 2+ uptake into GH 3 -derived microsomes was greatly reduced at 17°C. The effect of decreased temperatures on extracellular Ca 2+ influx was minor because the frequency and amplitude of spontaneous action potentials, which activate L-type Ca 2+ channels, was relatively unchanged at 17°C. These results suggest that in GH 3 secretory cells, Ca 2+ influx via L-type Ca 2+ channels initiates spontaneous [Ca 2+ ] i oscillations, which are then maintained by the combined activity of Ca 2+ -ATPase and Ca 2+ -induced Ca 2+ release from Tg/IP 3 -insensitive intracellular stores.

The purpose of this study was to identify whether the central extracellular fluid volume status following hypo- and hypervolaemia can be measured by the initial distribution volume of glucose or by the extravascular lung water. These two estimates were compared with the initial distribution volume of sucrose which has been used as an indicator for the measurement of the extracellular fluid volume. The above three estimates were determined by the administration of glucose, chilled saline and sucrose solutions, before and after haemorrhage (30 mL kg-1), and subsequent fluid load (lactated Ringer's solution 90 mL kg-1). The distribution volumes of glucose and sucrose decreased after haemorrhage and increased after fluid load compared with normovolaemic values, and a linear correlation was obtained between these two distribution volumes (r = 0.93, P < 0.001, n = 36). However, the extravascular lung water remained statistically unchanged throughout the procedure, despite a weak linear correlation with the sucrose distribution volume (r = 0.38, n = 33, P < 0.05). These results indicate that the initial distribution volume of glucose is more useful as an indicator of the central extracellular fluid volume status than the extravascular lung water.

A molluscicidal fraction occurs naturally in the bark of a vine (gogo in Tagalog), Entada phaseoloides, which grows indigeneously and abundantly in the Philippines. Butanol fraction of the methanol extracts of the bark was most toxic against Oncomelania quadrasi with the LC50 of 3.6-5.8 ppm. Analytical work on the butanol fraction by thin layer chromatography indicated that the active molluscicidal agents contained at least two kinds of saponins. The potency of E. phaseoloides remained rather stable over a wide range of pH values, in the presence of minerals and yeast cells and after ultraviolet irradiation of solutions. Our preliminary field trials, however, showed that doses as higher than 40 g per square meter would be needed to produce a satisfactory molluscicidal effect under field conditions.

Viral retinochoroiditis was induced experimentally by inoculation of herpes simplex virus into the vitreous body in rabbits. The animals were sensitized systemically using 2 pathogens as antigens (herpes simplex virus and toxoplasma gondii) 3 weeks prior to intraocular inoculation. Serum and intraocular fluid were collected 2 weeks after inoculation. The intraocular fluid antibody titers and quotients for these 2 pathogens were then measured to determine the effects of serum antibodies, which are thought to enter the eyes as a result of destruction of the blood-ocular barrier. Experimental criteria for antibody quotients were also determined. Antibody quotients for the etiological virus (herpes simplex virus) ranged from 2 to 20, with an average of 9.7. Those for toxoplasma gondii, the antibody of which is thought to enter the eye from the blood, were all less than 5 with average of 1.9. From these results, it would seem that when the antibody quotient of a pathogen in more than 6 in the intraocular fluid, it is likely to be an etiological organism, while the possibility of infection is very low when the quotient is under 2. More precise studies are required to identify an etiological pathogen when the quotient is 2-6.