Contribution of mutation I142M in fusion protein and Q44R in matrix protein of Newcastle disease virus to virulence in ducks

Although verogenic Newcastle disease viruses (NDVs) generally cause subclinical infection in waterfowls such as ducks, NDVs with high virulence in waterfowl have been sporadically reported. We previously reported that the NDV d5a20b strain, which is obtained by serial passaging of the velogenic 9a5b strain in domestic ducks, showed increased virulence in ducks (Hidaka et al., 2021). The d5a20b strain had 11 amino acid substitutions in its P/V, M, F, HN, and L proteins as compared to 9a5b. In the present study, we generated a series of recombinant (r) NDVs with these amino acid substitutions to identify the molecular basis of virulence of NDV in ducks, and evaluated their influences on virulence and in vitro viral properties. Each of the single amino acid substitutions in either the F protein I142M or the M protein Q44R contributed to the enhancement of intracerebral and intranasal pathogenicity in domestic ducks. The cell-cell fusion activity of the virus with F I142M was five times higher than that of the parental r9a5b. The virus with M Q44R rapidly replicated in duck embryo fibroblasts. Additionally, the rM+F+HN strain, which has the same amino acid sequences as d5a20b in M, F, and HN proteins, showed the highest level of virulence and replication efficiency among the generated recombinant viruses, nearly comparable to rd5a20b. These results suggest that multiple factors are involved in the high growth ability of NDV in duck cells, leading to increased virulence in vivo.     

Spatial–temporal evolution of the port–hinterland relationship: A case study of the Midstream Yangtze River,China

Most scientific attention on port studies centers on deep sea ports, especially container ports. In this paper, in contrast, attention is focused on the spatial–temporal development of inland waterway ports on the Midstream Yangtze River from 2001 to 2013. The aim of this study is to assess two relevant and complementary questions of the hinterland evolution: its geographical extent and the coordination relationship with the inland port. To conduct the study, it was necessary to first identify the boundaries of the ports' hinterlands within the given timeframe. Then, the coupling coordination degree model was introduced to explore the underlying relationship between the port service and hinterland economy. Furthermore, to better depict the intricate economic characteristics of the hinterland, the development stage theory was applied in the models. The results highlight the emergence of a discontinuous hinterland at Wuhan Port and its reinforcement of primacy with respect to fierce hinterland rivalry. It also demonstrates that an interplay between major ports and their corresponding hinterlands evolves from the transitional stage, characterized by lagging port service, to the multi‐stage, wherein the supply of ports partly outstrips hinterland demand.     

Quantitative assessment of muscle mass and gene expression analysis in dogs with glucocorticoid-induced muscle atrophy

The present study aimed to quantitatively evaluate muscle mass and gene expression in dogs with glucocorticoid-induced muscle atrophy. Five healthy beagles received oral prednisolone for 4 weeks (1 mg/kg/day), and muscle mass was then evaluated via computed tomography. Histological and gene expression analyses were performed using biopsy samples from the biceps femoris before and after prednisolone administration. The cross-sectional area of the third lumbar paraspinal and mid-femoral muscles significantly decreased after glucocorticoid administration (from 27.5 ± 1.9 to 22.6 ± 2.0 cm² and from 55.1 ± 4.7 to 50.7 ± 4.1 cm², respectively; P<0.01). The fast- and slow-twitch muscle fibers were both atrophied (from 2,779 ± 369 to 1,581 ± 207 μm² and from 2,871 ± 211 to 1,971 ± 169 μm², respectively; P<0.05). The expression of the growth factor receptor-bound protein 10 (GRB10) significantly increased after prednisolone administration (P<0.05). Because GRB10 suppresses insulin signaling and the subsequent mammalian target of rapamycin complex 1 activity, increased expression of GRB10 may have resulted in a decrease in protein anabolism. Taken together, 1 mg/kg/day oral prednisolone for 4 weeks induced significant muscle atrophy in dogs, and GRB10 might participate in the pathology of glucocorticoid-induced muscle atrophy in canines.     

Population structure of Solanum carolinense along the Takano River in Kyoto, Japan as determined by amplified fragment length polymorphism analysis

Areas infested with Solanum carolinense, an introduced perennial weed, have increased quickly in Japan. The genetic structure of a S. carolinense population along the Takano River in Kyoto, Japan was investigated using amplified fragment length polymorphism (AFLP) analysis to reveal how introductions and local spread have contributed to the development of this population. Along a terrace beside the river and an adjacent roadside, we defined a cluster of above‐ground shoots in the population as a subpopulation and 60 subpopulations were identified. Seventeen of these were selected and 165 shoots were analyzed by AFLP analysis using three primer pairs. The AFLP profiles revealed 69 genotypes and the presence of several clones, i.e. genotypes that were present in more than one individual. In total, 19 clones, comprising 2–34 identical genotypes, could be identified in the population. Each of these clones, except one, was allocated within each of the subpopulations. Clustering of the subpopulations was supported by high bootstrap values in all cases. Therefore, introductions from distant regions have mainly contributed to the development of this population, and local spread by seed or vegetative reproduction has rarely been important. The most likely introduction route of S. carolinense to this population was via planting associated with construction works.     

马尾松早期促进开花结实方法的研究

１９９７年在京山县太子山林场５年生马尾松无性系种子园内,用三种生长调节剂Ｃ．Ｃ．Ｃ．ＧＡ,ＢＡＰ分施用量、处理时期、处理次数三个因素进行叶面喷洒实验。结果表明ＢＡＰ有促进开花的作用。１９９８年在中心苗圃３年生嫁接苗实验区,利用１９９７年对促进开花结实有效果的ＢＡＰ进一步分时期、处理次数二因素进行了实验,结果表明ＢＡＰ对马尾松苗期开花也有明显的促进作用。两年的实验结果表明,ＢＡＰ能促进马尾松早期开花,这对缩短马尾松育种周期,加速新品种的开发具有非常现实的意义。     

Clinical evaluation of urinary liver-type fatty acid-binding protein for the diagnosis of renal diseases in dogs

Liver-type fatty acid-binding protein (L-FABP) is a biomarker for the early detection of renal diseases in humans. L-FABP is a cytotoxic oxidation product secreted from the proximal tubules under ischemic and oxidative stress conditions. First, L-FABP gene expression in the kidney and liver was evaluated. Next, the urinary L-FABP concentrations in dogs with or without renal diseases were measured using a novel enzyme-linked immunosorbent assay kit. Urinary L-FABP was normalized relative to urinary creatinine (uCre) concentrations (µg/g uCre). Finally, the relationships between urinary L-FABP and renal biomarkers used in canine medicine or serum alanine transaminase (ALT) as an indicator of liver damage were examined. Serum and urine samples from 94 client-owned dogs including 23 dogs with renal diseases and 71 dogs without renal diseases were used for analysis. Relative L-FABP gene expression was confirmed both in the liver and kidney. Dogs with renal diseases had a significantly higher urinary L-FABP than those without, and its predictive cutoff value was 26 µg/g uCre. Urinary L-FABP was significantly correlated with serum creatinine (r=0.4674, P<0.01), urea nitrogen (r=0.4907, P<0.01), urine specific gravity (r=−0.5100, P<0.01), and urine protein/creatinine ratio (r=0.7216, P<0.01), but not with serum ALT. Hence, dogs with a high urinary L-FABP value were more likely to have renal diseases.     

Endogenous 5-HT outflow from chicken aorta by 5-HT uptake inhibitors and amphetamine derivatives

Chemoreceptor cells aggregating in clusters in the chicken thoracic aorta contain 5-hydroxytryptamine (5-HT) and have voltage-dependent ion channels and nicotinic acetylcholine receptors, which are characteristics typically associated with neurons. The aim of the present study was to investigate the effects of 5-HT uptake inhibitors, fluvoxamine, fluoxetine and clomipramine (CLM), and amphetamine derivatives, p-chloroamphetamine (PCA) and methamphetamine (MET), on endogenous 5-HT outflow from the isolated chick thoracic aorta in vitro. 5-HT was measured by using a HPLC system with electrochemical detection. The amphetamine derivatives and 5-HT uptake inhibitors caused concentration-dependent increases in endogenous 5-HT outflow. PCA was about ten times more effective in eliciting 5-HT outflow than MET. The 5-HT uptake inhibitors examined had similar potency for 5-HT outflow. PCA and CLM increased 5-HT outflow in a temperature-dependent manner. The outflow of 5-HT induced by PCA or 5-HT uptake inhibitors was independent of extracellular Ca²⁺ concentration. The 5-HT outflow induced by CLM, but not that by PCA, was dependent on the extracellular NaCl concentration. These results suggest that the 5-HT uptake system of 5-HT-containing chemoreceptor cells in the chicken thoracic aorta has characteristics similar to those of 5-HT-containing neurons in the mammalian central nervous system (CNS).