Inhibition of flower stalk elongation and abnormal flower development by short-day treatment in a Japanese variety of Chinese chive (Allium tuberosum Rottler ex Sprengel)

Chinese chive is produced year-round in Japan, therefore it is important to demonstrate the relationships of short-day (SD) conditions with flower stalk elongation and flower formation for optimizing the cropping system, e.g. the increase in harvests per year. To clarify the influence of short photoperiod on flower stalk elongation and flower formation in Chinese chive, 8 h SD treatments were applied at different developmental stages of flower stalk elongation and flower formation. When the SD treatment started from vegetative or floral-initiated stages, the earlier the SD treatment started, the fewer flower stalks appeared. Also, the earlier the SD treatment started, the less the flowers bloomed and the more the flower stalk elongation was inhibited at the end of SD treatments. Many involucres did not open and withered with death of florets in SD when the SD treatment started between the umbel or flower bud differentiation and the perianth to stamen-formation stages. Also, all or part of the florets aborted and there were no complete inflorescences in the later SD treatments. We found that, in Chinese chive, the development of flower stalk elongation and flower formation were inhibited with the earlier SD treatment, after vegetative or floral-initiated stages. Furthermore, it is considered that Chinese chive needs long-day (LD) for the flower stalk elongation and inflorescence formation after the initiation of the flower bud. The plant has a qualitative LD requirement with the same photoperiodic requirement for both flower bud initiation and flower development.     

Modulating effect of acorn barnacle C-type lectins on the crystallization of calcium carbonate

ABSTRACT:   The modulating effect of invertebrate C-type lectins on the crystallization of calcium carbonate was investigated. The multiple C-type lectins, named BRA-1, -2 and -3, isolated from the acorn barnacle Megabalanus rosa inhibited the nucleation and growth of calcium carbonate crystals. Among BRA, BRA-2 most efficiently inhibited the crystal nucleation of aragonite and calcite at the concentrations of > 3.3 and > 26 μg/mL, respectively. The inhibitory activities of BRA were enhanced by the addition of various biomolecules such as D-glucosamine, D-galactosamine, chitosan oligosaccharides, L-arginine and L-aspartic acid. Although the crystals of aragonite and calcite were formed in the presence of lower concentrations of BRA, the shape and size of the crystals were changed. These results further indicate the participation of the lectins in biomineralization.     

Changes in crustacean hyperglycemic hormones in Pacific whiteleg shrimp Litopenaeus vannamei subjected to air-exposure and low-salinity stresses

Changes in crustacean hyperglycemic hormone (CHH)-family peptides in response to stress were investigated in Litopenaeus vannamei. Stress treatments consisted of air exposure and low salinity. High-performance liquid chromatography was used to quantify CHH-family peptides in the X-organ?Csinus gland complex (XO?CSG) in the eyestalks. Among the CHH-family peptides analyzed, only the level of sinus gland peptide-G (SGP-G) in the XO?CSG was decreased. SGP-G was also detectable by Western blotting analysis in the hemolymph of animals subjected to stress. These results suggest that SGP-G was secreted from the XO?CSG into the hemolymph during stress. Glucose levels in the hemolymph increased under conditions during which SGP-G was detected in the hemolymph. Hyperglycemia was also observed when SGP-G was injected. SGP-G may function to shift energy use to deal with stress.     

Dietary supplementation of red alga Pyropia spheroplasts on growth,feed utilization and body composition of sea cucumber,Apostichopus japonicus (Selenka)

A feeding experiment was conducted in a closed recirculating system to evaluate the effects of freeze‐dried spheroplasts prepared from Pyropia yezoensis (Ueda) on feed intake, growth and biochemical composition of sea cucumber, Apostichopus japonicus (Selenka). Pyropea spheroplasts (PS) were prepared through enzymatic treatment to break down the complex mixture of polysaccharides cell walls that might be easier for growth energy partitioning. Sea cucumbers were fed‐formulated diets with 10 (Diet 1), 30 (Diet 2) and 50 g/kg (Diet 3) inclusion level of PS. A diet without PS was used as a control (Diet 4). The experiment was conducted for 6 weeks maintaining water temperature 15 ± 1°C, photoperiod 18:06 hours (D:L). Feed was supplied ad‐libitum at 16.00 h once in a day, and the remaining feed and faeces were removed in the next day. Results showed that the highest growth was observed in the 50 g/kg PS diet compared to other treatments. Total weight gain, mean weight gain, net yield, protein efficiency ratio (PER) and protein gain (%) were significantly higher in the 50 g/kg PS diet (p < .05). A significantly higher percentage of energy was allocated for growth in the 50 g/kg PS diet. The highest specific growth rate and feed conversion efficiency (p < .05) were observed in the higher percentage of PS diet. Both the growth performance and biochemical analysis showed that superior growth was observed with increasing levels of PS in the diet. We infer that PS can be used as a new, cheaper feed ingredient in the formulated diet of A. japonicus.     

Immunohistochemical changes in production of pituitary hormones during artificial maturation of female Japanese eel <Emphasis Type="Italic">Anguilla japonica</Emphasis>

ABSTRACT:   Specific antibodies against follicle-stimulating hormone β subunit (FSHβ), prolactin (PRL), and somatolactin (SL) of the Japanese eel Anguilla japonica were produced. These antibodies, as well as antibodies against luteinizing hormone β subunit (LHβ) and growth hormone (GH) produced previously, were used to examine changes in the production of pituitary hormones in female eels during maturation induced by salmon pituitary homogenate (SPH) injection. Immunohistochemical observations showed a decrease in FSH production after SPH injection, suggesting that SPH inhibits FSH production. In contrast, LH production increased markedly with maturation. The number of GH producing cells decreased gradually during maturation, possibly because of inhibition by exogenous GH present in the SPH and/or endogenous insulin-like growth factor-I produced by the stimulation of salmon GH. Although changes in the number of PRL producing cells with maturation were not evident, the number of SL producing cells showed a peak at the late vitellogenic stages, and thereafter decreased to the migratory nucleus stage. These results suggest that GH and SL are involved in sexual maturation in SPH injected eels, as in other fishes.     

Correlation analysis of hypothalamic mRNA levels of appetite regulatory neuropeptides and several metabolic parameters in 28‐day‐old layer chickens

Various lines of evidence suggest that appetite‐related neuropeptides in the hypothalamus are regulated by adiposity signals such as leptin and insulin in mammals. In the present study, we examined age‐dependent changes in the weight of abdominal fat and hypothalamic mRNA levels of neuropeptide Y (NPY, an orexigenic neuropeptide) and proopiomelanocortin (POMC, a precursor of anorexigenic neuropeptides) in growing chickens at 7, 14, 21 and 28 days of age. Hypothalamic NPY mRNA levels were significantly (P < 0.05) decreased after 14 days of age, whereas hypothalamic POMC mRNA levels were significantly (P < 0.05) increased at 28 days of age. The percentage of abdominal fat was significantly increased after 14 days of age in chickens. We next examined the correlation of hypothalamic NPY and POMC mRNA levels and several parameters at 28 days of age. There were no significant correlations between hypothalamic mRNA levels of NPY or POMC and the percentage of abdominal fat. These findings suggest that the gene expressions of NPY and POMC do not depend on adiposity in chickens, at least in 28‐day‐old layer chickens.     

The urinary lipid profile in cats with idiopathic cystitis

Although feline idiopathic cystitis (FIC) distresses of many cats, its pathogenesis is unknown and the diagnosis is challenging. Polyunsaturated fatty acids (PUFAs) are metabolized into various lipid mediators. Lipid mediators such as prostaglandins (PGs) modulate inflammation and many of them are excreted into the urine. Thus, the investigation of the urinary lipid profile may reveal pathogenesis and help diagnosis of FIC. We collected urine samples from five FIC cats by spontaneous urination and analyzed 158 types of lipid mediators in urines using liquid chromatography-mass spectrometry. The urinary levels of PUFAs were higher in FIC compared to those of the healthy group. The excretions of a major inflammatory mediator, PGD₂, were less in FIC. Other well-known inflammatory mediators such as PGE₂, PGI₂, and their metabolites did not show a difference. In contrast, the levels of PGF_2α and its 2 metabolites and PGF_3α were higher in FIC. These results may provide new insights into the future management of cat FIC.     

Random dispersal of Bursaphelenchus xylophilus (Nematoda: Aphelenchoididae) in Pinus densiflora branches

Bursaphelenchus xylophilus is the causative agent of pine wilt disease. These nematodes disperse in the cortical and wood resin canals of host tree branches in the early stage of infection. To determine whether the dispersal can be regarded as diffusion, we inoculated B. xylophilus into living or boiled Pinus densiflora branch sections and investigated the spatial distribution 24 hr later. Assuming that some nematodes disperse randomly in the axial direction of branch sections and the rest remain at the inoculation site, the coefficient of diffusion (D) by dispersers was estimated to be 23.7–40.7 and 109.4 cm²/day for the living and boiled branches, respectively. The proportion of nondispersers was estimated to be 0.46–0.79 and 0.52 for the living and boiled branches, respectively. When the nematodes were inoculated at the centre of upright living branch sections, they dispersed up and down at similar D values of 7.4 and 7.9 cm²/day, respectively.     

Relationship between the biological activities of methylated derivatives of (-)-epigallocatechin-3-O-gallate (EGCG) and their cell surface binding activities

It was previously reported that (-)-epigallocatechin-3-O-gallate (EGCG) suppresses the expression of the high-affinity IgE receptor FcepsilonRI in human basophilic cells and that this suppressive effect is associated with EGCG binding to the cell surface. This study examined the effects of five methylated derivatives of EGCG, (-)-epigallocatechin-3-O-(3-O-methyl)gallate (EGCG 3' 'Me), (-)-epigallocatechin-3-O-(4-O-methyl)gallate (EGCG 4' 'Me), (-)-4'-O-methyl-epigallocatechin-3-O-gallate (EGCG 4'Me), (-)-epigallocatechin-3-O-(3,4-O-methyl)gallate (EGCG 3' '4' 'diMe), and (-)-4'-O-methyl-epigallocatechin-3-O-(4-O-methyl)gallate (EGCG 4'4' 'diMe) on FcepsilonRI expression and ERK1/2 phosphorylation, and each of their cell surface binding activities was measured. Of these five methylated derivatives, three that are methylated at the 3' '- and/or 4' '-position, EGCG 3' 'Me, EGCG 4' 'Me, and EGCG 3' '4' 'diMe, suppressed FcepsilonRI expression and ERK1/2 phosphorylation, although the suppressive effects were lower than that of EGCG. EGCG 4'Me and EGCG 4'4' 'diMe, both of which are methylated at the 4'-position, did not demonstrate a suppressive effect. Furthermore, it was found that EGCG 3' 'Me, EGCG 4' 'Me, EGCG 3' '4' 'diMe, and EGCG 4'Me, which are methylated at the 3' '- and/or 4' '-positions or the 4'-position, could bind to the cell surface even though their binding activities were lower than that of EGCG. Only EGCG 4'4' 'diMe, which is methylated at both the 4'- and 4' '-positions, could not bind. These results suggest that the trihydroxyl structure of the B ring is essential for EGCG to exert the suppressive effects and that the hydroxyl groups on both the 4'-position in the B ring and the 4' '-position in the gallate are crucial for the cell surface binding activity of EGCG.     

Rapid identification of Ochroconis gallopava by a loop-mediated isothermal amplification (LAMP) method

Ochroconis gallopava is a species of dematiaceous fungi recognized as a causative agent of zoonotic and emerging fungal infections. It affects the central nervous system and respiratory tracts of humans, birds and cats. We designed O. gallopava species-specific primer sets to aid in its identification by a loop-mediated isothermal amplification (LAMP) method based on the D1/D2 domain of the LSU rDNA sequence. The LAMP method successfully detected the gene from both fungal DNA and experimentally infected brains and spleens of mice and will be helpful in the diagnosis of O. gallopava infection.