Grouped, stacked rods and tapeta lucida in the retina of Japanese anchovy Engraulis japonicus

ABSTRACT: Morphology of the photoreceptor cells and tapetum of the Japanese anchovy Engraulis japonicus was studied by histologically and by chemical analysis. The Japanese anchovy has a duplex retina. The cones form parallel rows consisting of alternately placed long cones and bifid cones. Both types of cones are intimately associated and form triple units that are regularly spaced along the row of cones. The rods are grouped and stacked. This fish has a retinal tapetum lucidum composed of guanine and hypoxanthine. Three structures of the tapetum lucidum were recognized: platelet, diamond and rod types. Photomechanical changes include movements of the photoreceptor cells and the retinal tapetum. The retina of the Japanese anchovy is thought to be highly sensitive and well adapted to a dim light environment.     

Clinical pharmacokinetics of oseltamivir and its active metabolite oseltamivir carboxylate after oral administration in horses

The aim of this study was to investigate the pharmacokinetics of oseltamivir carboxylate (OC) in horses (n=6) after oral administration of its prodrug oseltamivir. The binding rate of OC to horse plasma proteins was negligible (<1%). Oral administration of oseltamivir of 2 mg/kg body weight of oseltamivir to horses provided a plasma concentration of OC (mean maximum concentration: 257.9 ng/ml) above the inhibitory concentrations against equine influenza A viruses determined in vitro. However, because OC is rapidly eliminated from horse plasma (mean elimination half-life: 2.5 hr), administration intervals should be less than 10 hr to retain a suitable concentration when using a single dose of 2 mg/kg oseltamivir.     

Hypertrophic cardiomyopathy in a mixed breed cat family

A spayed female mixed cat (case 1) and its female offspring, the result of a pairing between case 1 and its male sibling, were diagnosed with hypertrophic cardiomyopathy (HCM). A pedigree survey revealed that the prevalence of HCM was at least 12.5% in the family, which was considered to be significantly higher than that in a hospital-based population (approximately 1.6%). Thus, this finding seems to support the suspected occurrence of familial HCM in this group of related cats.     

Species composition of Modellidae and Cerambycidae (Coleoptera) in a coppice woodland

A continuous sampling of canopy beetles was carried out to determine variations in the abundance, species diversity, richness, and composition of the Mordellidae and Cerambycidae in a coppice woodland. Changes in the abundance and the species richness were monitored at three heights in the forest throughout the season in 1999, using yellow and blue water pan traps. The results showed significant variations in the abundance of Mordellidae among the canopy layers, while little variation was found for Cerambycidae. The abundance, species diversity, and richness were generally greater in summer. The results showed distinct species compositions in both families among layers.     

Lipid-rich bovine serum albumin improves the viability and hatching ability of porcine blastocysts produced in vitro

The effects of lipid-rich bovine serum albumin (LR-BSA) on the development of porcine blastocysts producedin vitro were examined. Addition of 0.5 to 5 mg/ml LR-BSA to porcine blastocyst medium(PBM) from Day 5 (Day 0 = in vitro fertilization) significantly increased the hatching ratesof blastocysts on Day 7 and the total cell numbers in Day-7 blastocysts. When Day-5 blastocysts were culturedwith PBM alone, PBM containing LR-BSA, recombinant human serum albumin or fatty acid-free BSA, addition ofLR-BSA significantly enhanced hatching rates and the cell number in blastocysts that survived compared withother treatments. The diameter, ATP content and numbers of both inner cell mass and total cells in Day-6 andDay-7 blastocysts cultured with PBM containing LR-BSA were significantly higher than in blastocysts culturedwith PBM alone, whereas LR-BSA had no effect on mitochondrial membrane potential. The mRNA levels of enzymesinvolved in fatty acid metabolism and β-oxidation (ACSL1, ACSL3,CPT1, CPT2 and KAT) in Day-7 blastocysts weresignificantly upregulated by the addition of LR-BSA. The results indicated that LR-BSA enhanced hatchingability and quality of porcine blastocysts produced in vitro, as determined by ATP content,blastocyst diameter and expression levels of the specific genes, suggesting that the stimulatory effects ofLR-BSA arise from lipids bound to albumin.     

利用FAKOPP评价树干杨氏弹性模量可行性研究

杨氏弹性模量是反映树干或板材抗弯、抗压强度的重要指标,是开展林木材质育种研究的重要内容。笔者通过对多株树分别采用FAKOPP(应力波速度测定机)和敲打法2种不同方法测量同一树干的杨氏弹性模量,并对2种测定数据进行相关性分析,检验用FAKOPP测量立木状态下树干弹性模量的准确性。通过对杨树试验证明:二者具有很强相关性,说明利用FAKOPP的方法能准确评价树干杨氏弹性模量大小。     

Improvement of an enzyme-linked immunosorbent assay for equine herpesvirus type 4 by using a synthetic-peptide 24-mer repeat sequence of glycoprotein G as an antigen

To increase the sensitivity of an enzyme-linked immunosorbent assay (ELISA) for equine herpesvirus type 4 (EHV-4) that uses a 12-mer peptide of glycoprotein G (gG4-12-mer: MKNNPIYSEGSL) [4], we used a longer peptide consisting of a 24-mer repeat sequence (gG4-24-mer: MKNNPIYSEGSLMLNVQHDDSIHT) as an antigen. Sera of horses experimentally infected with EHV-4 reacted much more strongly to the gG4-24-mer peptide than to the gG4-12-mer peptide. We used peptide ELISAs to test paired sera from horses naturally infected with EHV-4 (n=40). gG4-24-mer ELISA detected 37 positive samples (92.5%), whereas gG4-12-mer ELISA detected only 28 (70.0%). gG4-24-mer ELISA was much more sensitive than gG4-12-mer ELISA.     

Permuted tRNA genes expressed via a circular RNA intermediate in Cyanidioschyzon merolae

A computational analysis of the nuclear genome of a red alga, Cyanidioschyzon merolae, identified 11 transfer RNA (tRNA) genes in which the 3' half of the tRNA lies upstream of the 5' half in the genome. We verified that these genes are expressed and produce mature tRNAs that are aminoacylated. Analysis of tRNA-processing intermediates for these genes indicates an unusual processing pathway in which the termini of the tRNA precursor are ligated, resulting in formation of a characteristic circular RNA intermediate that is then processed at the acceptor stem to generate the correct termini.     

Influence of light intensity on feeding, growth, and early survival of leopard coral grouper (Plectropomus leopardus) larvae under mass-scale rearing conditions

This study investigated the effect of different light intensities on feeding, growth and survival of early stage leopard coral grouper Plectropomus leopardus larvae. Four different light intensities (0, 500, 1000 and 3000 lx) were used and larvae were kept under constant light conditions from 0 day after hatching (DAH) to 5 DAH. The larvae were fed a small S-type of Thai strain rotifers at a density of 20 individuals/mL from 2 DAH. The number of rotifers in larval digestive organ and total length of larvae were examined at 3 h intervals between 04:00 and 22:00 h on 3 DAH, and thereafter at 6 h intervals until the end of the experiment (5 DAH). Four experimental trials of the larval rearing were repeated using by 60 kL mass-scale rearing tanks. The results indicate that coral grouper larvae are visual feeders and their food intake increases with increasing light intensity. Food intake of larvae reared at 3000 lx was significantly higher than those reared at 0–1000 lx on 3 DAH despite being the first-feeding day (P < 0.01). On 4 DAH, total length of larvae reared at 3000 lx was significantly larger than those reared at the lower light intensities (0, 500 and 1000 lx), and thereafter light intensity significantly influenced larval feeding and growth until the end of the experiment. Survival on 5 DAH did not show a significant difference between light intensities, but survival rate at 3000 lx and 1000 lx had a tendency to be higher than those reared at the lower light intensities (0 and 500 lx). In contrast, larvae reared at 0 lx exhibited stagnant and/or negative growth. These results indicate that light intensity is significantly the factor affecting larval feeding, growth, and survival in coral grouper larvae under the rearing conditions.