Substance P-like immunoreactive nerve fibers in the pars distalis of the anterior pituitary in the dog

Summary The pars distalis of the anterior pituitary is known to be regulated by hypothalamic hormones. Recently, we have discovered the presence of substance P-like immunoreactive nerve fibers in the pars distalis of the monkeys. Substance P-like immunoreactivity in the pars distalis of the dog was investigated in this study. A substantial amount of substance P-like immunoreactive nerve fibers with a large amount of varicosities were found. They were widely distributed in the gland, more abundant along its periphery. Most of them were closely related to the glandular tissue, some were located on vascular walls. Substance P-like immunoreactive nerve fibers were also found in the meningeal sheath of the anterior pituitary. They could be followed into the parenchyma of the gland.     

Foliar Spraying of 6-Benzylaminopurine Promotes Growth and Flavonoid Accumulation in Mulberry (Morus alba L.)

Journal of Plant Growth Regulation - Mulberry (Morus alba L.) leaf, a “source of both medicine and food”, contains antioxidant ingredients such as flavonoids, alkaloids and polyphenols....     

长江安庆新洲水域鱼类群落结构及多样性

沙洲水域环境良好,饵料资源丰富,栖息生境多样,为鱼类的生长繁殖提供了优良的生存环境。为了解长江安庆新洲水域鱼类群落结构特征,于2017年4月、7月、10月和12月对安庆江段新洲水域鱼类群落进行季节性调查。共采集鱼类64种,分属5目11科48属,其中62.5%为鲤科鱼类。以物种数和多样性指数分析群落多样性特征,结果表明新洲水域鱼类种类多样性水平较高。单因素方差分析表明,该群落多样性季节差异显著(P0.05),空间差异不明显。新洲水域鱼类群落优势种为鳊(Parabramis pekinensis Basilewsky, 1855)、鲤(Cyprinus carpio Linnaeus, 1758)、贝氏■(Hemiculter bleekeri Warpachowsky, 1887)、银鮈(Squalidus argentatus Sauvage et Dabry, 1874)和似鳊(Pseudobrama simoni Bleeker, 1864)。4种摄食功能群中,杂食性(42.19%)和肉食性(35.94%)鱼类物种数比例较高;3种生态类群中,淡水定居性鱼类占绝对优势(84.37%);3种栖息水层类型中,底层鱼类物种数比例较高,占37.50%。大型经济鱼类占总渔获物比例低(0.01%),但个体较大,因而相对重要性指数(IRI)高。总体上,新洲鱼类群落多样性和丰富度指数较高,均匀度指数偏低,个体小型化趋势明显。捕捞强度过大、水利工程建设导致的江湖阻隔及外来物种入侵是新洲水域渔业资源衰退的主要因素。由此,建议持续开展长江渔业资源监测,加强长江干流沙洲水域渔业资源保护。     

Heterogeneous Coupling between Interdependent Lattices Promotes the Cooperation in the Prisoner’s Dilemma Game

In the research realm of game theory, interdependent networks have extended the content of spatial reciprocity, which needs the suitable coupling between networks. However, thus far, the vast majority of existing works just assume that the coupling strength between networks is symmetric. This hypothesis, to some extent, seems inconsistent with the ubiquitous observation of heterogeneity. Here, we study how the heterogeneous coupling strength, which characterizes the interdependency of utility between corresponding players of both networks, affects the evolution of cooperation in the prisoner’s dilemma game with two types of coupling schemes (symmetric and asymmetric ones). Compared with the traditional case, we show that heterogeneous coupling greatly promotes the collective cooperation. The symmetric scheme seems much better than the asymmetric case. Moreover, the role of varying amplitude of coupling strength is also studied on these two interdependent ways. Current findings are helpful for us to understand the evolution of cooperation within many real-world systems, in particular for the interconnected and interrelated systems.     

Human Alzheimer’s disease synaptic <Emphasis Type="Italic">O</Emphasis>-GlcNAc site mapping and iTRAQ expression proteomics with ion trap mass spectrometry

Neuronal synaptic functional deficits are linked to impaired learning and memory in Alzheimer’s disease (AD). We recently demonstrated that O-GlcNAc, a novel cytosolic and nuclear carbohydrate post-translational modification, is enriched at neuronal synapses and positively regulates synaptic plasticity linked to learning and memory in mice. Reduced levels of O-GlcNAc have been observed in AD, suggesting a possible link to deficits in synaptic plasticity. Using lectin enrichment and mass spectrometry, we mapped several human cortical synaptic O-GlcNAc modification sites. Overlap in patterns of O-GlcNAcation between mouse and human appears to be high, as previously mapped mouse synaptic O-GlcNAc sites in Bassoon, Piccolo, and tubulin polymerization promoting protein p25 were identified in human. Novel O-GlcNAc modification sites were identified on Mek2 and RPN13/ADRM1. Mek2 is a signaling component of the Erk 1/2 pathway involved in synaptic plasticity. RPN13 is a component of the proteasomal degradation pathway. The potential interplay of phosphorylation with mapped O-GlcNAc sites, and possible implication of those sites in synaptic plasticity in normal versus AD states is discussed. iTRAQ is a powerful differential isotopic quantitative approach in proteomics. Pulsed Q dissociation (PQD) is a recently introduced fragmentation strategy that enables detection of low mass iTRAQ reporter ions in ion trap mass spectrometry. We optimized LTQ ion trap settings for PQD-based iTRAQ quantitation and demonstrated its utility in O-GlcNAc site mapping. Using iTRAQ, abnormal synaptic expression levels of several proteins previously implicated in AD pathology were observed in addition to novel changes in synaptic specific protein expression including Synapsin II.     

The Stress Hormone Corticosterone Increases Synaptic ��-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid (AMPA) Receptors via Serum- and Glucocorticoid-inducible Kinase (SGK) Regulation of the GDI-Rab4 Complex

Corticosterone, the major stress hormone, plays an important role in regulating neuronal functions of the limbic system, although the cellular targets and molecular mechanisms of corticosteroid signaling are largely unknown. Here we show that a short treatment of corticosterone significantly increases α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)-mediated synaptic transmission and AMPAR membrane trafficking in pyramidal neurons of prefrontal cortex, a key region involved in cognition and emotion. This enhancing effect of corticosterone is through a mechanism dependent on Rab4, the small GTPase-controlling receptor recycling between early endosome and plasma membrane. Guanosine nucleotide dissociation inhibitor (GDI), which regulates the cycle of Rab proteins between membrane and cytosol, forms an increased complex with Rab4 after corticosterone treatment. Corticosterone also triggers an increased GDI phosphorylation at Ser-213 by the serum- and glucocorticoid-inducible kinase (SGK). Moreover, AMPAR synaptic currents and surface expression and their regulation by corticosterone are altered by mutating Ser-213 on GDI. These results suggest that corticosterone, via SGK phosphorylation of GDI at Ser-213, increases the formation of GDI-Rab4 complex, facilitating the functional cycle of Rab4 and Rab4-mediated recycling of AMPARs to the synaptic membrane. It provides a potential mechanism underlying the role of corticosteroid stress hormone in up-regulating excitatory synaptic efficacy in cortical neurons.     

Characterization of a novel 14 kDa bile acid-binding protein from rat ileal cytosol

A 14 kDa polypeptide in rat ileal cytosol has been identified as the major intestinal cytosolic bile acid-binding protein (I-BABP) by photoaffinity labeling with the radiolabeled 7,7-azo derivative of taurocholate (7,7-azo-TC). To further characterize I-BABP, the protein was purified by lysylglycocholate Sepharose 4B affinity and DE-52 anion-exchange chromatography. The purified I-BABP contained a single 14 kDa band on SDS-PAGE. The 14 kDa protein showed a 26-fold increase in binding affinity for [3H]7,7-azo-TC compared to cytosolic protein. Immunoblotting of protein fractions separated by affinity chromatography showed that neither liver fatty acid binding protein (L-FABP) nor intestinal fatty acid binding protein (I-FABP) bind to the affinity column and that the 14 kDa protein which bound to the column and was subsequently eluted with detergent did not cross-react with anti-L-FABP or anti-I-FABP. The 14 kDa protein labeled with [3H]7,7-azo-TC was radioimmunoprecipitated from cytosol by rabbit antiserum raised against purified I-BABP. I-BABP was shown to have a blocked N-terminus; however, its mixed internal sequence generated from cyanogen bromide-cleaved protein and amino acid composition indicated that it was related to (although clearly distinct from) both I-FABP and L-FABP. These studies have isolated a 14 kDa bile acid-binding protein from rat ileal cytosol which is immunologically and biochemically distinct from I-FABP and L-FABP.     

Preparation of cross-linked carboxymethyl chitosan for repairing sciatic nerve injury in rats

A successful nerve regeneration process was achieved with nerve repair tubes made up of 1-ethyl-3(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) cross-linked carboxymethyl chitosan (CM-chitosan) with improved biodegradability. Chitosan has a very slow degradation rate, while the EDC cross-linked CM-chitosan tubes degraded to 30% of original weight during 8 weeks of incubation in lysozyme solution. In vitro cell culture indicated that the CM-chitosan films presented no cytotoxicity to Schwann cells. From in vivo studies using a 10 mm rat sciatic nerve defect model investigated by histomorphometry analysis, the average diameter of the fibers and the average thickness of myelin sheath in the CM-chitosan tubes were 3.7 ± 0.33 and 0.33 ± 0.04 μm, respectively, which demonstrated equivalence to nerve autografts (the current “gold” standard); furthermore, the average fiber density in the CM-chitosan tubes was 20.5 × 10³/mm², which was similar to that of autografts (21 × 10³/mm²) and significantly higher than that of common chitosan tubes (15.3 × 10³/mm²).     

Ethanol production from pentoses and sugar-cane bagasse hemicellulose hydrolysate by Mucor and Fusarium species

The fermentation of carbohydrates and hemicellulose hydrolysate by Mucor and Fusarium species has been investigated, with the following results. Both Mucor and Fusarium species are able to ferment various sugars and alditols, including d-glucose, pentoses and xylitol, to ethanol. Mucor is able to ferment sugar-cane bagasse hemicellulose hydrolysate to ethanol. Fusarium F5 is not able to ferment sugar-cane bagasse hemicellulose hydrolysate to ethanol. During fermentation of hemicellulose hydrolysates, d-glucose was utilized first, followed by d-xylose and l-arabinose. Small amounts of xylitol were produced by Mucor from d-xylose through oxidoreduction reactions, presumably mediated by the enzyme aldose reductase¹ (alditol: NADP⁺ 1-oxidoreductase, EC 1.1.1.21). For pentose fermentation, d-xylose was the preferred substrate. Only small amounts of ethanol were produced from l-arabinose and d-arabitol. No ethanol was produced from l-xylose, d-arabinose or l-arabitol.