Development and age‐related change of cerebrovascular noradrenergic (NA) innervation in the Japanese quail

Development of cerebrovascular noradrenergic (NA) innervation was investigated in the Japanese quail, using histofluorescence technique and quantitative analysis. Cerebral perivascular NA nerves arose from the cerebral carotid (CCA), internal ethmoidal (IEA) and vertebral (VA) arteries before hatching, with the first appearance on the CCA and IEA at embryonic day (E) 8 and of the VA at E14. Nerves arising from the IEA were greater in number and spread more rapidly than those from the CCA and VA. On E16, fluorescent fiber bundles lying on the anterior circulation subdivided rapidly into thin fibers. Consequently, the number of NA nerves over the arterial system increased greatly at hatching, particularly along the distal portion of the anterior ramus. At the same developmental stage, all the major arteries of the anterior and posterior circulation were almost entirely covered by NA nerves. The abrupt reorganization of cerebrovascular NA innervation in newborn quails may be related to some specific trophic and vasomotor roles for structural and functional improvement of the cerebral circulation that is required for its brain differentiation at this critical period of development. The supply of NA nerves to the anterior and posterior circulations sequentially increased during development from posthatching day (P) 1–15. Plexuses of NA nerves in each of the major cerebral arteries at P22 and P42–50 were similar in meshwork construction to each other, and to those seen at P15. Likewise, there was no clear statistical difference in the nerve density of the corresponding arteries among the three posthatching ages, except for the caudal basilar artery.     

运用RAPD法识别杨树品种技术的研究

在正确提取ＤＮＡ后,探讨了在成本最低、效果最好的基础上,得出了ＤＮＡ最佳增殖反应液的组成（１０Ｘｂｕｆｆｅｒ１．５０、ｄｎｔｐｓ ０．３０、ＭｇＣｌ２ ０．６０、灭菌水 １０．５７、Ｐｒｉｍｅｒ１．００、Ｔａｇ０．０３、ＤＮＡ１．００）,其次用 ６０个引物对杨柳科属和杨属的 １３个品种进行了人工分析,发现多态标记 ３２个,用其中的任意 １３个标记就能区别 １３品种。     

Development of the musculature and muscular abnormalities in larval seven-band grouper Epinephelus septemfasciatus

There are a number of reports documenting skeletal development in groupers, but surprisingly little is known about muscle development. We have documented muscle development in the seven-band grouper Epinephelus septemfasciatus (Thunberg), focusing primarily on the cranial muscles from 0 days post-hatching (dph) to 28 dph, using a modified whole mount immunohistochemical staining method. The eye muscles developed first followed by the cheek muscles, which completed development prior to first feeding. The muscles associated with the opercle and the levator internus 1 developed gradually and were not linked to first feeding. Later, between 12 and 16 dph, the muscle composition in the dorsal branchial arches changed to the adult form. We observed a number of cultured larvae that exhibited abnormal musculature in the body and jaw. Our results provide the first documentation of muscle development in larval seven-band grouper. This information can be used to detect abnormalities during development and provide a marker to assess the effect of changes in larval rearing techniques.     

Spontaneous captive breeding and larval development in the green and red variants of the Japanese sea cucumber Apostichopus japonicus (Selenka 1867)

We report the spontaneous spawning, larval development, survival rate and larval growth rate patterns observed in the green and red variants of the Japanese sea cucumber Apostichopus japonicus. The green variant adapted well to the captive conditions in the Sasebo City Fisheries Center and spontaneously spawned without any induction or stimulation. One hundred individual green variants spawned nine times and produced approximately 155 million eggs. In contrast, 50 individual red variants showed poor adaptation to captivity and spawned spontaneously only three times, producing about 12 million eggs. Larval development and growth rate pattern was almost identical between the two variants of A. japonicus. In contrast, the larval survival rate for the green variant was over 90% up to the auricularia stage (10 days), but much low (less than 30%) for the red variant. We demonstrated that the green variant of A. japonicus was easier to rear in captivity. This provides a useful method for maintaining sustainable harvests and eventually contributing to restocking and sea ranching of the existing population. Further studies about optimal ecological conditions and behaviour are needed to improve egg production and survival rate of the red variant of A. japonicus.     

Effect of inorganic ions on bud cell formation by <Emphasis Type="Italic">Fusarium oxysporum</Emphasis> in potato dextrose broth

Potato dextrose broth (PDB), a well-known medium for cultivation of fungi, can be made from potato extract and glucose (handmade PDB) or bought as a commercial powder (commercial PDB). Previously, we reported that bud cell formation and fungal biomass of Fusarium oxysporum in handmade PDB are higher than in commercial PDB, and the presence of high molecular weight (>20 MDa) carbohydrates in PDB promoted bud cell formation by most strains of F. oxysporum. In this study, we report the effects of inorganic ions in PDB on bud cell formation and fungal biomass production by F. oxysporum. Concentrations of Mg, K, Fe, PO₄ ³⁻ and SO₄ ²⁻ were higher and of Na and Cl⁻ were lower in handmade PDB than in commercial PDB. Adding each inorganic ion alone to commercial PDB showed that Mg is critical for enhancement of bud cell formation by some strains of F. oxysporum. The addition of Mg²⁺ with raw potato starch to commercial PDB promoted bud cell formation by some, but not all, of the seven F. oxysporum strains tested in this study.     

The discovery of pyridalyl: a novel insecticidal agent for controlling lepidopterous pests

Synthesis of analogues of two compounds with known insecticidal activity, both of which contain a 3,3-dichloro-2-propenyloxy group, produced 2-(trifluoromethyl)-4-phenoxyphenyl 3,3-dichloro-2-propenyl ether, which had weak activity against lepidopterous larvae. Structural modifications around this lead compound led to the development of pyridalyl [Pleo, S-1812; 2,6-dichloro-4-(3,3-dichloroallyloxy)phenyl 3-[5-(trifluoromethyl)-2-pyridyloxy]propyl ether], which belongs to a new class of insecticides. Pyridalyl gives very good control of various lepidopterous and thysanopterous pests on cotton and vegetables, without phytotoxicity. It controls populations of Heliothis virescens F and Plutella xylostella (L) which are resistant to various currently used insecticides. It also produces unique insecticidal symptoms, so it may have a different mode of action from other existing insecticides. Pyridalyl is also less harmful than existing insecticides to various beneficial arthropods, so it should provide an important tool in IPM and insecticidal management programmes for the control of lepidopterous and thysanopterous pests. The first market introduction is expected in Japan and some Asian countries in the years between 2004 and 2005.     

Involvement of stathmin in proliferation and differentiation of immortalized human endometrial stromal cells

Uterine endometrial stromal cells differentiate into decidual cells during the late secretory phase of the menstrual cycle and pregnancy. However, the biochemical mechanisms of decidualization have yet to be definitively elucidated. In the present study, we transfected primary human endometrial stromal cell with a temperature-sensitive mutant of simian virus 40 large T antigen and thereby established an immortalized stromal cell line (EtsT) in order to examine the role of stathmin, a cytosolic phosphoprotein that regulates microtubule dynamics, in stromal cell differentiation. When treated with the decidual stimulus dibutyryl-cAMP (db-cAMP) or forskolin, the fibroblastic cell-shaped EtsT cells transformed into large- and round-shaped cells and secreted large amounts of the decidual markers prolactin (PRL) and insulin-like growth factor binding protein-1 (IGFBP-1). Analysis of the stathmin protein levels in the db-cAMP- and forskolin-treated EtsT cells revealed that the total and phosphorylated protein levels dropped as decidualization progressed. Suppression of stathmin expression by transfection with small interfering RNA (siRNA) suppressed EtsT cell proliferation. It also abolished db-cAMP-induced PRL and IGFBP-1 mRNA expression and protein secretion. Thus, stathmin expression can be considered an integral factor regulating the initial stage of the process of human endometrial stromal cell differentiation.     

Effects of taurine levels in broodstock diet on reproductive performance of yellowtail Seriola quinqueradiata

The effect of dietary taurine was investigated on reproductive performance in yellowtail Seriola quinqueradiata. Two-year-old fish of average body weight 6.1kg were fed on diets containing three levels of taurine (T-0, T-0.5 or T-1.0%) for 5 months prior to spawning. For spawning investigations, fish were induced to maturity by human chorionic gonadotrop in injection (600 IU/kg-fish) and artificially inseminated. Oocyte growth improved significantly (P<0.05) with the increase of dietary taurine. The collection of eggs from females reared on the T-0% diet was not successful. The success rate of spawning for females fed on T-0.5 and 1.0% diets was one out of six, and six out of seven, respectively. The taurine levels of the liver and serum in the T-0% diet group were much lower than that in the T-0.5 and T-1.0% diet groups (P<0.05). Fish fed the T-0% diet showed higher contents of serine in the liver and serum. The taurine content of the ovary was not significantly different among the different dietary treatments. These results indicate that taurine has a positive effect on the improvement of spawning performance of yellowtail.