Genomic Structure of a Geminivirus in the Genus Begomovirus from Yellow Vein-affected Eupatorium makinor

A virus from yellow vein-affected Eupatorium makinoi was tentatively designated as Eupatorium-infecting geminivirus (EuGV) on the basis of whitefly transmissibility, electron microscopic observation of geminate particles in sap and symptomatology. EuGV-speciflc DNA fragments were obtained by polymerase chain reaction (PCR). Based on the restriction analysis of the PCR products, EuGV was suggested to have a monopartite genome. We determined the putative, complete nucleotide sequence of the EuGV genome which is comprised of 2766 nucleotides. The EuGV sequence had two virus sense open reading frames (ORF)(V1, V2), four complementary sense ORFs (C1–C4) and a non-coding region termed the intergenic region. This genome structure is quite similar to other monopartite begomoviruses already reported. The nucleotide and amino acid sequences were compared with other begomoviruses. The results supported the conclusion that EuGV is distinct and divergent from other begomoviruses, whereas potential sequence motifs reported in other geminiviruses are well conserved. Received 17 March 1999/ Accepted in revised form 12 November 1999     

Mapping the relative risk of surface water acidification based on cumulative acid deposition over the past 25 years in Japan

Sensitivity maps of atmospheric acid deposition in Japan have not been updated in 20 years. Here, we propose new relative risk maps of surface water acidification in forests based on a weighted overlay of cumulative potential acid deposition (CPAD) simulated for a 25-year period (1981–2005), including the sensitivities of soil and bedrock to acidification. We assumed that relative acidification risk is high in areas that exhibit high sensitivities of soil and bedrock to acid and have received a large amount of cumulative acid deposition over the past several decades. We aggregated fine soil and bedrock maps into a 20-km mesh for overlay onto an 80-km mesh map of CPAD by considering their spatial structures in Japan. Allocation of the weights among CPAD and soil and bedrock sensitivities was performed based on observational trends in river pH over the past 30 years. The resulting risk map for surface water acidification showed that large areas of western Japan, as well as smaller areas of Hokkaido, Tohoku, Kanto, and Kyushu, are at high risk of surface water acidification. Seventy-seven percent of all rivers for which a declining trend in pH was observed from 2001 to 2009 were also high-risk areas. Acid deposition might be one factor controlling surface water acidification in areas with high bedrock sensitivity, in addition to high CPAD and soil sensitivity, although the risk of soil acidification remains unclear.     

Relationship between growth hormone (GH) pulses in the peripheral circulation and GH-releasing hormone and somatostatin profiles in the cerebrospinal fluid of goats

Growth hormone (GH) is secreted in a pulsatile manner, but the underlying mechanisms of GH pulse generation remain to be resolved. In the present study, we investigated the relationship between GH pulses in the peripheral circulation and GH-releasing hormone (GHRH) and somatostatin (SRIF) profiles in the cerebrospinal fluid (CSF) of male goats. The effects of an intracerebroventricular (icv) injection of neuropeptide Y (NPY), galanin and ghrelin were also analyzed. Blood and CSF samples were collected every 15 min for 8 hr from the jugular vein and third ventricle, respectively. GH pulsatility in the goat was found to consist of distinct large pulses of 5 hr periodicity and small pulses of 1 hr periodicity. GHRH and SRIF in the CSF fluctuated in a pulsatile manner with 1 hr periodicity, and most of the descending phase of SRIF pulses were associated with the initiation of GH pulses. Icv injections of NPY, galanin and ghrelin stimulated GHRH release without affecting SRIF release. In addition, NPY suppressed, and galanin and ghrelin induced large GH pulses, although ghrelin was much more effective than galanin. These results suggest that an hourly fall in SRIF is involved in generating intrinsic circhoral rhythm of GH pulsatility. The mechanisms underlying the generation of large GH pulses of 5 hr periodicity remain unknown, while direct action of NPY and/or ghrelin on the pituitary might be involved.     

Increased locomotor activity,increased food and water intake and decreased PVN neurons in H1 calponin gene-deficient mice

Calponin (h1 or basic) is an actin-binding protein that is expressed abundantly in smooth muscle. Our previous study using h1 calponin-null mutant mice demonstrated that h1 calponin inhibits the shortening velocity of smooth muscle contraction without significantly affecting the amplitude of force production. Furthermore, early onset of osteogenesis and increased bone formation have been reported in mutated mice. In the present study, we examined the effect of h1 calponin depletion on the metabolism and behavior of mice and found that the mutated mice showed increased locomotor activity, as well as increased intake of food and water, associated with the decreased number of neurons in the paraventricular nucleus of the hypothalamus (PVN).     

Involvement of activin and inhibin in the regulation of food and water intake in the rat

The expression of activin and inhibin has been demonstrated in the hypothalamus, but their physiological roles in the brain remain to be elucidated. In the present study, involvement of activin and inhibin in the regulation of food and water intake was examined. Male rats were deprived of food or water for 12 and 60 hr, and mRNA levels of activin/inhibin alpha, betaA and betaB subunits in the hypothalamus were estimated by RT-PCR. Gene expression of alpha subunit transiently decreased at 12 hr of food deprivation, while it did not change during water deprivation. Food and water deprivation for 60 hr increased mRNA levels of betaA and betaB subunits, respectively. These results indicated that gene expression of each subunit was independently regulated. Injection of activin A (0.5 and 4.0 microg) into the third ventricle decreased food intake. Water intake was suppressed by 4.0 microg, but not 0.5 microg, of activin A. Intracerebroventricular injection of inhibin A (0.5 and 4.0 microg) decreased water intake in a dose dependent manner without affecting food intake, suggesting that inhibin could act independently of activin. Taken together, it is suggested that activin and inhibin take part in the central regulation of nutrient and fluid balance, though further study is needed to determine precise molecular species involved.     

Distribution of Arcobacter species among livestock in Japan

A survey was conducted to examine the distribution of Arcobacter species among livestock in Japan. During May 1999 and May 2000, fecal samples from cattle (n=332) and swine (n=250), chicken cloacal swabs (n=234), and vaginal swabs of cattle (n=61) and swine (n=15) were submitted for the isolation of Arcobacter species. Arcobacter species were isolated from 3.6 and 10.0% of the cattle and swine fecal samples, respectively, along with 14.5% of chicken cloacal swabs. No significant seasonal differences were observed. Species-specific polymerase chain reaction assay showed that A. butzleri was the most prevalent species (83.3, 60.0 and 47.1% of the cattle, swine and chicken isolates, respectively), followed by A. cryaerophilus 1B (16.7, 36.0 and 55.9% of the cattle, swine and chicken isolates, respectively). Of the samples from vaginal swabs, 8.1 and 13.3% were positive for Arcobacter in cattle and swine, respectively. This is the first report demonstrating the distribution of Arcobacter species among livestock in Japan.     

Characterization of Staphylococcus aureus strains isolated from bovine mastitis in Japan

Fifty-three strains of Staphylococcus aureus isolated from cows affected with mastitis from 21 prefectures in Japan were characterized by phenotypic and genotypic methods. Thirty-three (62.3%) strains showed biotype K-beta+CV:A, coagulase type VI, and sensitivity to bovine phages of group III or IV. These 33 strains could be subdivided into two groups on the basis of the production of staphylococcal enterotoxins (SEs) and on toxic shock syndrome toxin-1 (TSST-1). By pulsed-field gel electrophoresis, the 16 SEC- and TSST-1-producing strains showed similar patterns that differed by only a few fragments, suggesting that they were genetically closely related. Fifteen of 17 non SEC-producing strains which did not produce any other SEs and TSST-1 were genetically different from the SEC-producing strains and showed genetic diversity.     

Spatially resolved calcium dynamics of mammalian Purkinje cells in cerebellar slice

Microfluorometric imaging was used to study the correlation of intracellular calcium concentration with voltage-dependent electrical activity in guinea pig cerebellar Purkinje cells. The spatiotemporal dynamics of intracellular calcium concentration are demonstrated during spontaneous and evoked activity. The results are in agreement with hypotheses of dendritic segregation of calcium conductances suggested by electrophysiological experiments. These in vitro slice fluorescence imaging methods are applicable to a wide range of problems in central nervous system biochemical and electrophysiological functions.     

Endocarditis in chickens caused by subclinical infection of Streptococcus gallolyticus subsp. gallolyticus

Streptococcus gallolyticus subsp. gallolyticus causes endocarditis in humans and acute septicemia in domestic birds. We describe here the infective endocarditis caused by the bacterium found among clinically healthy broilers at two abattoirs in Japan. The chickens were thought to be healthy because of the lack of clinical symptoms and normal levels of mortality before slaughtering. At the time of inspection, some chickens were condemned because of organ disorders characterized by vegetative valvular endocarditis as well as focal necrosis in heart, liver, and spleen. Streptococcus gallolyticus subsp. gallolyticus was isolated from the organs as a pure culture, indicating that the bacterium probably was the causative agent of the disorders. Amplified fragment length polymorphism analysis of the isolates collected at the abattoirs from chickens grown in nine different farms indicated that the isolates were different variants of the same clonal lineage and may have been derived from the same ancestor. These results suggest that S. gallolyticus subsp. gallolyticus causes infectious endocarditis in chickens and that healthy chickens may possess the bacterium in their normal flora as an opportunistic pathogen.