A recombinant vaccine of H5N1 HA1 fused with foldon and human IgG Fc induced complete cross-clade protection against divergent H5N1 viruses

Development of effective vaccines to prevent influenza, particularly highly pathogenic avian influenza (HPAI) caused by influenza A virus (IAV) subtype H5N1, is a challenging goal. In this study, we designed and constructed two recombinant influenza vaccine candidates by fusing hemagglutinin 1 (HA1) fragment of A/Anhui/1/2005(H5N1) to either Fc of human IgG (HA1-Fc) or foldon plus Fc (HA1-Fdc), and evaluated their immune responses and cross-protection against divergent strains of H5N1 virus. Results showed that these two recombinant vaccines induced strong immune responses in the vaccinated mice, which specifically reacted with HA1 proteins and an inactivated heterologous H5N1 virus. Both proteins were able to cross-neutralize infections by one homologous strain (clade 2.3) and four heterologous strains belonging to clades 0, 1, and 2.2 of H5N1 pseudoviruses as well as three heterologous strains (clades 0, 1, and 2.3.4) of H5N1 live virus. Importantly, immunization with these two vaccine candidates, especially HA1-Fdc, provided complete cross-clade protection against high-dose lethal challenge of different strains of H5N1 virus covering clade 0, 1, and 2.3.4 in the tested mouse model. This study suggests that the recombinant fusion proteins, particularly HA1-Fdc, could be developed into an efficacious universal H5N1 influenza vaccine, providing cross-protection against infections by divergent strains of highly pathogenic H5N1 virus.     

Mixotrophy in the newly described phototrophic dinoflagellate Woloszynskia cincta from western Korean waters: feeding mechanism, prey species and effect of prey concentration

Woloszynskia species are dinoflagellates in the order Suessiales inhabiting marine or freshwater environments; their ecophysiology has not been well investigated, in particular, their trophic modes have yet to be elucidated. Previous studies have reported that all Woloszynskia species are photosynthetic, although their mixotrophic abilities have not been explored. We isolated a dinoflagellate from coastal waters in western Korea and established clonal cultures of this dinoflagellate. On the basis of morphology and analyses of the small/large subunit rRNA gene (GenBank accession number=FR690459), we identified this dinoflagellate as Woloszynskia cincta. We further established that this dinoflagellate is a mixotrophic species. We found that W. cincta fed on algal prey using a peduncle. Among the diverse prey provided, W. cincta ingested those algal species that had equivalent spherical diameters (ESDs) ≤12.6 μm, exceptions being the diatom Skeletonema costatum and the dinoflagellate Prorocentrum minimum. However, W. cincta did not feed on larger algal species that had ESDs≥15 μm. The specific growth rates for W. cincta increased continuously with increasing mean prey concentration before saturating at a concentration of ca. 134 ng C/ml (1,340 cells/ml) when Heterosigma akashiwo was used as food. The maximum specific growth rate (i.e. mixotrophic growth) of W. cincta feeding on H. akashiwo was 0.499 d(-1) at 20 °C under illumination of 20 μE/m(2) /s on a 14:10 h light-dark cycle, whereas its growth rate (i.e. phototrophic growth) under the same light conditions without added prey was 0.040 d(-1). The maximum ingestion and clearance rates of W. cincta feeding on H. akashiwo were 0.49 ng C/grazer/d (4.9 cells/grazer/d) and 1.9 μl/grazer/h, respectively. The calculated grazing coefficients for W. cincta on co-occurring H. akashiwo were up to 1.1 d(-1). The results of the present study suggest that grazing by W. cincta can have a potentially considerable impact on prey algal populations.     

旱作小麦覆膜穴播栽培综合效应

缺水、干旱是制约宁南山区农业生产发展,特别是限制旱作农田生产力水平提高的首要问题。小麦是宁南山区第一大作物,其中,旱作种植约占９０％。近年来,利于提高旱作小麦抗旱、节水性能的品种选用和栽培技术研究没有大的突破,使其生产出现了较长时期的徘徊局面。因此,对旱作小麦从农业技术和农水结合入手,找出一条投资少、见效快、节水、抗旱、增产、增效的新出路,已明显摆在我们面前。宁南山区春、夏季气温分布特征及存在于７月份的热季、热干风天气过程,形成了小麦出苗期长,分蘖期、幼穗分化期、籽粒灌浆期短的“一长三短”生育…     

Immobilization of lipase from Candida rugosa on Sepabeads(®): the effect of lipase oxidation by periodates

The objective of this paper was the investigation of a suitable Sepabeads^? support and method for immobilization of lipase from Candida rugosa. Three different supports were used, two with amino groups, (Sepabeads^? EC-EA and Sepabeads^? EC-HA), differing in spacer length (two and six carbons, respectively) and one with epoxy group (Sepabeads^? EC-EP). Lipase immobilization was carried out by two conventional methods (via epoxy groups and via glutaraldehyde), and with periodate method for modification of lipase. The results of activity assays showed that lipase retained 94.8% or 87.6% of activity after immobilization via epoxy groups or with periodate method, respectively, while glutaraldehyde method was inferior with only 12.7% of retention. The immobilization of lipase, previously modified by periodate oxidation, via amino groups has proven to be more efficient than direct immobilization of lipase via epoxy groups. In such a way immobilized enzyme exhibited higher activity at high reaction temperatures and higher thermal stability.     

Comparison of mammalian VIP bioactivities in dispersed acini from guinea pig pancreas

Mammalian VIP is identical in pig, cow, human, rat, dog and goat but differs in the guinea pig (GP) in positions 5, 9, 19, and 26. We now demonstrate that GP, goat, rat and synthetic mammalian VIP are indistinguishable in their inhibition of binding of 125I-labelled synthetic VIP to dispersed acini from GP pancreas and that GP, pig, dog, goat and synthetic VIP are also similar in their efficacy and potency in stimulating amylase release from these acini. Thus in spite of the differences in amino acid sequence, GP VIP appears to have full biologic potency in its action on dispersed acini from GP pancreas.     

Peripheral versus central components of the effects of dermorphin on intestinal motility in the fed rat

The effects of subcutaneous (s.c.), intraperitoneal (i.p.), intrathecal (i.t.) and intracerebroventricular (i.c.v.) injection of dermorphin (DER) on intestinal myoelectrical activity were examined in fed rats with chronically implanted electrodes on the small and large bowel. DER s.c. restored the 'fasting' pattern of duodenal activity, i.e., the migrating myoelectric complex (MMC), corresponding to an inhibition by about 40% of the fed pattern for 120 min at a dose as small as 0.5 nM per rat. DER i.p. strongly inhibited (about 65%) the fed pattern for 120 min. A fasting pattern lasting 80 min, or a marked inhibition lasting 150 min were recorded after 0.5 nM DER i.t. or i.c.v., respectively. On the contrary, the colonic pattern of activity was inhibited by DER whatever the route used, although the duration of inhibition was different from each other. For both the small and large intestine, similar doses of DER were more efficient by i.c.v. than by i.t. routes, and by i.p. than by s.c. routes. A plurality of sites of action is suggested, including local receptors which are activated, particularly at the duodenal level by i.p. DER (0.5 nM). The supraspinal component of the immediate effects of i.c.v. DER (0.1 nM) were demonstrated by a preferential effect on the colon that was even more intense than after i.t. DER.     

Alzheimer’s Disease-Related Protein Expression in the Retina of Octodon degus

New studies show that the retina also undergoes pathological changes during the development of Alzheimer’s disease (AD). While transgenic mouse models used in these previous studies have offered insight into this phenomenon, they do not model human sporadic AD, which is the most common form. Recently, the Octodon degus has been established as a sporadic model of AD. Degus display age-related cognitive impairment associated with Aβ aggregates and phosphorylated tau in the brain. Our aim for this study was to examine the expression of AD-related proteins in young, adult and old degus retina using enzyme-linked or fluorescence immunohistochemistry and to quantify the expression using slot blot and western blot assays. Aβ4G8 and Aβ6E10 detected Aβ peptides in some of the young animals but the expression was higher in the adults. Aβ peptides were observed in the inner and outer segment of the photoreceptors, the nerve fiber layer (NFL) and ganglion cell layer (GCL). Expression was higher in the central retinal region than in the retinal periphery. Using an anti-oligomer antibody we detected Aβ oligomer expression in the young, adult and old retina. Immunohistochemical labeling showed small discrete labeling of oligomers in the GCL that did not resemble plaques. Congo red staining did not result in green birefringence in any of the animals analyzed except for one old (84 months) animal. We also investigated expression of tau and phosphorylated tau. Expression was seen at all ages studied and in adults it was more consistently observed in the NFL-GCL. Hyperphosphorylated tau detected with AT8 antibody was significantly higher in the adult retina and it was localized to the GCL. We confirm for the first time that Aβ peptides and phosphorylated tau are expressed in the retina of degus. This is consistent with the proposal that AD biomarkers are present in the eye.     

Drosophila S6 Kinase Like Inhibits Neuromuscular Junction Growth by Downregulating the BMP Receptor Thickveins

Synaptic connections must be precisely controlled to ensure proper neural circuit formation. In Drosophila melanogaster, bone morphogenetic protein (BMP) promotes growth of the neuromuscular junction (NMJ) by binding and activating the BMP ligand receptors wishful thinking (Wit) and thickveins (Tkv) expressed in motor neurons. We report here that an evolutionally conserved, previously uncharacterized member of the S6 kinase (S6K) family S6K like (S6KL) acts as a negative regulator of BMP signaling. S6KL null mutants were viable and fertile but exhibited more satellite boutons, fewer and larger synaptic vesicles, larger spontaneous miniature excitatory junctional potential (mEJP) amplitudes, and reduced synaptic endocytosis at the NMJ terminals. Reducing the gene dose by half of tkv in S6KL mutant background reversed the NMJ overgrowth phenotype. The NMJ phenotypes of S6KL mutants were accompanied by an elevated level of Tkv protein and phosphorylated Mad, an effector of the BMP signaling pathway, in the nervous system. In addition, Tkv physically interacted with S6KL in cultured S2 cells. Furthermore, knockdown of S6KL enhanced Tkv expression, while S6KL overexpression downregulated Tkv in cultured S2 cells. This latter effect was blocked by the proteasome inhibitor MG132. Our results together demonstrate for the first time that S6KL regulates synaptic development and function by facilitating proteasomal degradation of the BMP receptor Tkv.