The effects of migration on the immunity of Black-Headed Gulls (Chroicocephalus ridibundus: Laridae)

In order to elucidate the relationship between migration period and immunity related to susceptibility, we conducted research on Black-headed gulls (Chroicocephalus ridibundus). We captured 260 gulls and collected their peripheral blood. Their leukocyte (WBC) count, percentages of heterophils (Het) and lymphocytes (Lym), heterophil and lymphocyte ratio (H/L ratio), and CD4 and CD8α expression levels (CD4 and CD8α, respectively) were quantitatively analyzed over three migration periods (Autumn migration, Wintering, Spring migration). In Adult gulls, WBC counts and CD4 levels significantly increased. Moreover, the Het and H/L ratio decreased from the Autumn migration to Wintering. Conversely, only WBC counts and CD4 levels measurements significantly decreased from Wintering to Spring migration (P<0.05). The tested parameters of the Tokyo-bay population show a greater significant difference than the measurements of immunity of the Mikawa-bay population. This study suggests that the migratory period has a negative effect on an aspect of the immune system. Including the period-difference in the immune systems in the local population, it is necessary to investigate the relationship between the ecology of migratory birds and their immunity.     

Comparison of corn gluten meal and meat meal as a protein source in dry foods formulated for cats

OBJECTIVE: To compare the nutritional value of corn gluten meal (CGM) and meat meal (MM) as a dietary source of protein in dry food formulated for adult cats. ANIMALS: 8 healthy adult cats (4 males and 4 females). PROCEDURE: Diets containing CGM or MM as the main protein source were each fed for a 3-week period in a crossover study. Digestibility and nutritional balance experiments were conducted during the last 7 days of each period. Furthermore, freshly voided urine was obtained to measure urinary pH, struvite crystals, and sediment concentrations. RESULTS: Daily food intake and dry-matter digestibility were significantly higher for the MM diet. Fecal moisture content also was higher for the MM diet. Apparent nitrogen (N) absorption and N retention were higher for the MM diet, even when values were expressed as a percentage to account for differences in N intake. Urinary pH, struvite activity product, number of struvite crystals in urine, and urinary sediment concentrations were not different between diets. Retention of calcium, phosphorus, and magnesium was lower for the CGM diet, and cats lost body calcium and magnesium when fed the CGM diet. CONCLUSIONS AND CLINICAL RELEVANCE: Meat meal was superior to CGM as a protein source in dry foods formulated for cats, because dry-matter digestibility and N utilization were higher for the MM diet. In addition, net loss of body calcium and magnesium for the CGM diet suggests that mineral requirements increase when CGM is used as a protein source.     

The first record of sucking louse, Neohaematopinus callosciuri, infesting pallas squirrels in Japan

A species of sucking louse, Neohaematopinus callosciuri, was found for the first time in Japan. The species was found on an invasive species of squirrel, Pallas squirrel, Callosciurus erythraeus, in the Kamakura district, Kanagawa Prefecture, Japan. A total of 52 lice were obtained from 22 of 104 squirrels captured. The lice were about three times more prevalent in male squirrels than in females and were detected most frequently in the winter. As N. callosciuri has never been reported on wild animals in Japan, this species probably was introduced into Japan along with their host, Pallas squirrels.     

Suppression of feline coronavirus replication in vitro by cyclosporin A

ABSTRACT: The feline infectious peritonitis virus (FIPV) is a member of the feline coronavirus family that causes FIP, which is incurable and fatal in cats. Cyclosporin A (CsA), an immunosuppressive agent that targets the nuclear factor pathway of activated T-cells (NF-AT) to bind cellular cyclophilins (CyP), dose-dependently inhibited FIPV replication in vitro. FK506 (an immunosuppressor of the pathway that binds cellular FK506-binding protein (FKBP) but not CyP) did not affect FIPV replication. Neither cell growth nor viability changed in the presence of either CsA or FK506, and these factors did not affect the NF-AT pathway in fcwf-4 cells. Therefore, CsA does not seem to exert inhibitory effects via the NF-AT pathway. In conclusion, CsA inhibited FIPV replication in vitro and further studies are needed to verify the practical value of CsA as an anti-FIPV treatment in vivo.     

Analysis of rice <Emphasis Type="Italic">RNA-dependent RNA polymerase 1</Emphasis> (<Emphasis Type="Italic">OsRDR1</Emphasis>) in virus-mediated RNA silencing after particle bombardment

RNA-dependent RNA polymerases (RDRs) play a key role in various RNA silencing pathways in many organisms. Using the nucleotide sequence of SGS2/SDE1/RDR6 in Arabidopsis as the search query for sequences that flank the insertions of rice retrotransposon Tos17, we selected rice mutant lines (OsRDR1). RT-PCR analysis showed that OsRDR1 mRNA was undetectable in leaves and calli of the mutants, while it was detected in wild type. RNA silencing was induced by particle bombardment to investigate any effects of OsRDR1 on RNA silencing with β-glucuronidase or green fluorescent protein DNA/RNA in the mutant lines. The results showed that RNA silencing was impaired in these mutant lines by inverted repeat (IR) DNA or in vitro transcribed double-stranded RNA. Further, the mutant lines were bombarded with Brome mosaic bromovirus (BMV, a ssRNA virus) or Wheat dwarf geminivirus (WDV, a ssDNA virus), each carrying the IR sequence of a reporter gene. As a result, RNA silencing was impaired by BMV. Interestingly, however, it was not impaired by WDV. Thus we propose that OsRDR1 is required for RNA silencing mediated by Bromovirus, but not by Geminivirus in this system.     

Emergence and frequency of highly benzimidazole-resistant Colletotrichum gloeosporioides, pathogen of Japanese pear anthracnose, after discontinued use of benzimidazole

From July to October 1999, two Japanese pear varieties, Housui and Niitaka, were unexpectedly infected with Colletotrichum gloeosporioides causing anthracnose in Saga Prefecture of Japan. More than 90?% of the anthracnose fungus strains collected in 1999 were highly benzimidazole-resistant and distributed at high frequencies across pear-producing areas. The control of anthracnose by benzimidazole fungicides could not be confirmed in orchards where the isolation frequency of resistant strains was high. The frequency of resistant strains did not significantly decline, even 2?C5?years after the last use of benzimidazole fungicides.     

Identification of potato scab-causing Streptomyces sp. occurring in strongly acidic soils in Saga Prefecture in Japan

Acid scab of potatoes occurs frequently in strongly acidic soils at pH 3.9–5.2. On the basis of the phylogenetic relationships derived from 16S rDNA sequences and physiological characteristics, we identified the organism causing this disease in potatoes grown in the Uwaba district of Saga Prefecture, Kyushu Island, southwest Japan, as Streptomyces acidiscabies. Another pathogen that occurred more frequently in weakly acidic to neutral soils, rather than strongly acidic soils, was identified as S. scabiei. Streptomyces acidiscabies tended to produce superficial lesions, while S. scabiei mostly produced raised and/or erumpent lesions.     

L-leucine: a neuroactive substance in insects

A compound was isolated from the blood of silkworm larvae, Bombyx mori, which had been prostrated with DDT; this compound increased the spontaneous discharge in the isolated abdominal nerve cord of the American cockroach, Periplaneta americana. The compound was identified as L-leucine.     

Aboveground productivity of an unsuccessful 140-year-old <Emphasis Type="Italic">Cryptomeria japonica</Emphasis> plantation in northern Kyushu,Japan

We measured the aboveground biomass, biomass increment and litterfall production of a 140-year-old, abandoned Cryptomeria japonica plantation in order to infer the effects of topography on biomass production. The plantation was unsuccessful and the naturally regenerated broad-leaved trees contributed 93.4% (374.2 Mg ha⁻¹) of the total aboveground biomass (400.2 Mg ha⁻¹). Comparing between different slope positions, aboveground biomass decreased downslope corresponding to the decrease in broad-leaved tree biomass. The biomass of C. japonica did not vary with slope position. Biomass increment and litterfall production of the broad-leaved trees also decreased downslope. However, litterfall production per unit biomass and aboveground net primary production per unit biomass increased downslope. Results of a path analysis showed that biomass increment of C. japonica decreased with increasing topographical convexity, whereas biomass and litterfall production of broad-leaved tree increased. Litterfall production of broad-leaved tree decreased with increasing biomass of C. japonica, suggesting that, despite their small biomass, the presence of residual C. japonica may have negative effects on the distribution and productivity of the broad-leaved trees. Our results indicated that total aboveground biomass of the study site was comparable to that of old-growth C. japonica plantations. We inferred that the variation in aboveground biomass of the broad-leaved trees was largely determined by the topography, while their productivity was affected by interactions with planted C. japonica.     

土槿皮乙酸B增加活性氧水平诱导人乳腺癌MCF-7细胞凋亡和衰老的研究

本研究旨在研究土槿皮乙酸B(PAB)诱导人乳腺癌MCF-7细胞凋亡和衰老与活性氧的关系。在相差显微镜下观察4 μmol/L PAB在36 h诱导细胞凋亡小体的出现;LDH方法显示PAB时间依赖性的增加凋亡比率;SA-β-半乳糖苷酶显示4 μmol/L PAB作用3 d后,去药再作用5 d,96%的细胞蓝染,细胞变大且扁平;流式细胞仪检测用DCFH-DA染色后4 μmol/L PAB 时间依赖性增加细胞内活性氧水平。所以4 μmol/L PAB通过增加细胞内活性氧水平促进细胞凋亡和衰老。