A karyomorphological study of the genusHypericum (Hypericaceae) in Japan

Chromosome numbers were determined in 226 collections ofHypericum of Japan, representing nine species and one interspecific hybrid. These included the first cytological records forH. erectum var.caespitosum, H. samaniense, H. hakonense, H. sikokumontanum, H. kamtschaticum var.kamtschaticum, H. kamtschaticum var.hondoense, H. pseudopetiolatum, H. yojiroanum andH. tosaense. Counts of 2n=16 were made throughout for collections of six species, and those of 2n=18 forH. ascyron. Intraspecific polyploidy was found inH. samaniense (2x and 3x, x=8) andH. pseudopetiolatum (2x and 4x, x=8). Results of the karyotype analysis showed that three different karyotypes could be recognized, and they were parallel to the subdivision ofHypericum by Kimura (1951). The chromosomes were very small and mostly median centromeric. It was suggested that the role of polyploidy in the evolutionary differentiation ofHypericum in Japan might have been rather limited.     

DEMOGRAPHIC PARAMETERS OF INDO-PACIFIC BOTTLENOSE DOLPHINS (TURSIOPS ADUNCUS) AROUND MIKURA ISLAND, JAPAN

Long-term identification surveys were conducted using video records on Indo-Pacific bottlenose dolphin ( Tursiops aduncus ) around Mikura Island, Tokyo, Japan. On 246 surveys, 3,996 min of video were recorded during each summer season from 1994 to 2001. Two hundred and twenty individuals were observed, including juveniles and neonates, that were not cataloged, but could be identified by association with their mothers. Over the eight-year study period, the total number of identified and cataloged individuals was 169. The annual number of newly identified dolphins stabilized at ∼ 10 after 1995. In the middle of each research season, a plateau in the number of reidentified individuals was reached. Most of the dolphins were observed frequently–percentages of reidentified dolphins in adjoining years were greater than 86% and 62 individuals were seen consecutively during the eight years. There were no significant differences in the sex ratio between years. The sex ratio was skewed significantly towards male for subadults and towards female for adults. The survival rate of one-year-old calves was 86.7%, and the mean age at weaning was 3.5 yr. The calving interval averaged 3.4 yr among adult females. The mean annual birth, fecundity, and recruitment rates were 0.071, 0.239, and 0.068, respectively. Mikura Island is located in the pelagic ocean with no protected bay area existing around the island. Dolphins do not regularly inhabit any other locations besides Mikura within the Izu island chain. Thus, this island may be important core habitat of these dolphins.     

Role of the p70 S6 kinase cascade in neutrophilic differentiation and proliferation of HL-60 cells-a study of transferrin receptor-positive and -negative cells obtained from dimethyl sulfoxide- or retinoic acid-treated HL-60 cells

Previously, we suggested that p70 S6 kinase (p70 S6K) plays an important role in the regulation of neutrophilic differentiation of HL-60 cells; this conclusion was based on our analysis of transferrin receptor (Trf-R) positive (Trf-R(+)) and negative (Trf-R(-)) cells that appeared after treatment with dimethyl sulfoxide (Me(2)SO). In this study, we analyzed the upstream of p70 S6K in relation to the differentiation and proliferation of both cell types. The granulocyte colony-stimulating factor (G-CSF)-induced enhancement of phosphatidylinositol 3-kinase (PI3K) activity in Trf-R(+) cells was markedly higher than that in Trf-R(-) cells. Wortmannin, a specific inhibitor of PI3K, partially inhibited G-CSF-induced p70 S6K activity and G-CSF-dependent proliferation, whereas rapamycin, an inhibitor of p70 S6K, completely inhibited these activities. The wortmannin-dependent enhancement of neutrophilic differentiation was similar to that induced by rapamycin. From these results, we conclude that the PI3K/p70 S6K cascade may play an important role in negative regulation of neutrophilic differentiation in HL-60 cells. For the G-CSF-dependent proliferation, however, p70 S6K appears to be a highly important pathway through not only a PI3K-dependent but also possibly an independent cascade.     

How a small enterprise improved the conditions of night and shift work using local resources

A small oxygen factory in Cantho Province located in the Mekong Delta Area in the southern part of Vietnam was studied to provide practical support measures to improve night and shift work. A direct observation study and a fatigue symptom survey during the work were conducted. The factory applied discontinuous two-shift systems in two teams. Depending on customers' demands, they frequently prolonged oxygen production until midnight. The study results showed work-related risks such as carrying heavy oxygen cylinders, workers' sleepiness during the night work, and increased fatigue feelings among production operators. Based on the study results, better strategies for night and shift work schedules such as regular work hours minimizing overtime and night work were discussed with the managers and workers. A follow-up visit three months later confirmed many improvements undertaken in the factory. Better work arrangements for night and shift workers were made including local lighting, resting corners, filling the height gaps on the work floors, and clear work instructions. Prolonged mid-night shift was stopped. It was concluded that local small enterprises in Vietnam have much potential to improve their conditions of shift and night work once practical support measures based on their local practice is given.     

Captive environment influences the composition and diversity of fecal microbiota in Indo-Pacific bottlenose dolphins,Tursiops aduncus

Captive environments impact the microbiota of captive animals; however, the comparison of microbiota between wild and captive dolphins has been poorly investigated. To explore the impact of a captive environment, we characterized the fecal microbiota of nine wild and four captive Indo-Pacific bottlenose dolphins, Tursiops aduncus, using a next-generation sequencing and revealed differences in the fecal microbiota between the analyzed groups. Statistical differences in abundances of the phyla Firmicutes and Proteobacteria were found between the wild and captive dolphins. Thirty-six genera (22.9% of the total genera detected in all dolphins) were shared between the groups, whereas 79 (50.3%) and 42 (26.8%) genera were found only in the wild or captive dolphins, respectively. Several pathogenic bacterial genera, including Morganella and Mycoplasma, were detected only in the captive dolphins, and the genus Lactobacillus was found only in the wild dolphins. LefSe and SIMPER analyses revealed that the genus Clostridium sensu stricto 1 was significantly more abundant in the captive dolphins than in the wild ones and contributed the most to the dissimilarity of fecal microbiota between the groups. Our results indicate that the captive environment impacts the fecal microbiota of dolphins and reinforces the importance of monitoring potentially pathogenic bacteria in captivity.