Short-term storage and cryopreservation of Urechis unicinctus (Echiura: Urechidae) sperm

In the present study, attempts were made to preserve Urechis unicinctus sperm at 4°C. Cryopreservation procedures were optimized for various cryoprotectants and freezing rates, equilibration times and dilution ratios. During short‐term storage, the motility of undiluted sperm was extended for 6 days of cold storage,and in 70% and 100% artificial seawater only persisted for 2 and 4 days respectively. The survival rate of undiluted sperm was maintained at a high level accordingly. After cryopreservation, the highest motility and survival rate (41.5±2.2%) were obtained in 15% dimethyl sulphoxide (Me₂SO) using a freezing rate of 30°C min^?1. After thawing the sperm cryopreserved in glycerol lost almost all motility. The motility and survival rate of post‐thawing sperm did not show significant differences after 8 and 15 min equilibration using 15% Me₂SO as cryoprotectant; the values were significantly higher than those of 2 min equilibration. Comparisons of motility and survival rate between treatments pooled by dilution ratio showed that the effect of 1:1 ratio (sperm volume to cryoprotectant volume) was best. There was no difference between 1:3 and 1:5, and other ratioswere significantly worse.     

对山东某猪场一起仔猪腹泻的流行病学调查

本文针对发生腹泻疫情的某猪场开展了实验室检测和流行病学调查,实验室检测表明该疫情的病原为猪流行性腹泻病毒。流行病学调查显示,此次腹泻疫情于2013年11月份开始暴发,2014年3月份结束,发病猪的种类具有明显的次序,育肥猪首先发生,其次是母猪,新生仔猪最后发病;发病率和死亡率与猪的种类、日龄密切相关,育肥猪和母猪发病后仅出现腹泻症状而不死亡,仔猪发病后腹泻症状明显而且死亡率随着年龄的增长急剧下降,3日龄以下仔猪死亡率可达100%,1周龄仔猪死亡率降至72.73%,12日龄仔猪死亡率仅有10%。对猪场风险因素分析表明,饲料车辆直接进入猪场、卖猪车辆与饲养人员接触、粪便通道没有封闭、饲养人员流动等是影响此次腹泻疫情的高风险因素,通过降低高风险因素很好地控制了疫病。     

Protective efficacy of a live attenuated Mycoplasma hyopneumoniae vaccine with an ISCOM-matrix adjuvant in pigs

An attenuated Mycoplasma hyopneumoniae vaccine that requires intrathoracic administration is commercially available for use against mycoplasmal pneumonia in China. Given the limitations of such a route of administration, this study was undertaken to assess the capacity of an ISCOM-matrix adjuvant to enhance immunogenicity following intramuscular use. Immune responses in pigs following vaccination and subsequent intra-tracheal bacterial inoculation were examined using lymphocyte proliferation, serology and mucosal IgA in both nasal and saliva swabs.Vaccination induced clear lymphocyte proliferation, but only slight serum antibody responses although these were significantly increased following experimental infection. Mucosal IgA was not detected in either nasal or salivary secretions. Following bacterial challenge, animals vaccinated with the adjuvant-containing live vaccine exhibited less severe pulmonary lesions (median score 3.67) than unvaccinated pigs (median score 13.58). The degree of ciliary loss on the respiratory tract surface was reduced in vaccinated pigs compared with experimentally infected controls. The findings indicated that the adjuvant vaccine administered IM provided protection against experimentally induced mycoplasmal pneumonia and could have commercial potential.     

Breaking seasonal limitation: year-round sporogenesis in the brown alga Laminaria saccharina by blocking the transport of putative sporulation inhibitors

Year-round induction of sporogenesis of Laminaria saccharina was performed by mechanically blocking the transport of the putative sporulation inhibitors produced by the blade meristem and culturing the plants in constant short days. Sporogenesis was successfully induced by removal of the blade meristem, either by cultivating distal blade fragments or by performing a transverse cut in the frond. The earliest sorus formation after artificial induction was 10 days. The age of the sporophytes used for induction was 6–11 months or 2 years in tank-grown or field-collected sporophytes, respectively. Zoospores were successfully released in all cases. Thus, by year-round artificial induction of sporogenesis, (1) sporeling production of L. saccharina and thereafter sporophyte cultivation could be achieved without seasonal limitation, and (2) the life cycle of L. saccharina (from spore to spore) could be completed within 8 months under controlled conditions.     

Ochracenoids A and B,Guaiazulene-Based Analogues from Gorgonian Anthogorgia ochracea Collected from the South China Sea

Two new guaiazulene-based analogues, ochracenoids A (1) and B (2), along with four known analogues (3–6), were isolated from the gorgonian Anthogorgia ochracea collected from the South China Sea. The planar structures of the new compounds were elucidated by comprehensive spectroscopic data. The absolute configuration of 1 was determined as 3R by the comparison of TDDFT calculated electronic circular dichroism with its experimental spectrum. Compound 1 is a rare guaiazulene-based analogue possessing a unique C₁₆ skeleton. The possible generation process of 1 through an intermolecular one-carbon-transfer reaction was also discussed. Compound 2 was previously described as a presumed intermediate involved in the biogenesis of anthogorgienes A and I. Compound 3 exhibited antiproliferative effects on the embryo development of zebrafish Danio rerio.     

Study on differences of reaction behavior of phenolic hydroxyl groups with vinyl sulfone reactive dyes and monochlorotriazine reactive dyes

Using p-methylphenol as a model compound for phenolic hydroxyl groups on silk fibroin, the reaction kinetics of two typical of reactive dyes including vinyl sulfone reactive dyes and monochlorotriazine reactive dyes with phenolic hydroxyl groups were studied by reverse phase ion-pair high-performance liquid chromatography. The results showed that, the reaction rates of monochlorotriazine reactive dyes with phenolic hydroxyl groups were by far faster than those of vinyl sulfone reactive dyes, attributed to the stability of resultants from the former. The optimum reaction conditions for phenolic hydroxyl groups with vinyl sulfone reactive dyes and monochlorotriazine reactive dyes were at 50–70 °C and pH=8–9 for the former, and at 85–95 °C and pH=8–9 for the latter. The methods and results in this paper would help to deeply study the reaction mechanisms of reactive dyes with silk fibroin.     

Effects of environment parameters on sol-gel transition and dry-spinnability of regenerated silk fibroin aqueous solution

Protein concentration, pH, the types and concentrations of metallic ions, and extensional flow are thought to be important environment parameters affecting the natural spinning process. In this study, we investigate the effects of the types and concentrations of metallic ions (Ca²⁺, Mg²⁺, and K⁺ ions), pH, and silk fibroin concentration on the sol-gel transition and the rheological behavior of a regenerated silk fibroin (RSF) aqueous solution. The results show that with an increase in the silk fibroin concentration, the weak acidic RSF aqueous solutions containing Mg²⁺ or Ca²⁺ ions undergo a phase transition to a weak gel state. Moreover, the rheological characterization of RSF aqueous solutions shows a dramatic change, and their apparent viscosities increase by almost three orders of magnitude and approach the apparent viscosity of the native dope in the silkworm gland. By using conventional pressure equipment, we investigate the dry-spinnability of weak gels. Further, we observe that the as-spun fibers exhibit a smooth surface and have inferior mechanical properties. The structure of the as-spun fibers is predominantly in a random coil or Silk I conformation.     

The synthesis of core-shell monodisperse P(St-MAA) microspheres and fabrication of photonic crystals Structure with Tunable Colors on polyester fabrics

The core-shell monodisperse P(St-MAA) microspheres with different diameters ranging from 200 nm to 400 nm were prepared by soap-free emulsion copolymerization, in which styrene (St) and methacrylic acid (MAA) were polymerizable monomers, and ammonium persulfate (APS) acted as initiator. The diameters and monodispersity of P(St-MAA) microspheres could be controlled by adjusting the concentrations of styrene, methacrylic acid and ammonium persulfate. The core-shell structure and chemical component distribution of the P(St-MAA) microspheres were confirmed by TEM and XPS. The photonic crystals on polyester fabrics with three-dimensionally ordered arrangement were fabricated by self-assembly of gravitational sedimentation with P(St-MAA) microspheres and exhibited brilliant structural colors without any chemical dyes and pigments. SEM, TEM and crystallographic analysis were applied to confirm a face centered cubic (fcc) structure of the photonic crystals on polyester fabrics. The versatile structural colors of the photonic crystals were dependent on the photonic band-gap which could be regulated by the spherical size of P(St-MAA) microspheres and viewing angles. This technology may provide a new strategy to color the fabrics and reduce the pollution in the current textile industry.     

Water-Soluble Polysaccharides Extracted from Pueraria lobata Delay Aging of Caenorhabditis elegans under Heat Stress

Plant Foods for Human Nutrition - Pueraria lobata is a perennial legume, commonly used as a food source in China. The polysaccharides extracted from P. lobata have demonstrated various biological...