Expression of gamma-aminobutyric acid type A receptor α_2 subunit in the dorsal root ganglion of rats with sciatic nerve injury

The γ-aminobutyric acid neurotransmitter in the spinal cord dorsal horn plays an important role in pain modulation through primary afferent-mediated presynaptic inhibition. The weakening of γ-aminobutyric acid-mediated presynaptic inhibition may be an important cause of neuropathic pain. γ-aminobutyric acid-mediated presynaptic inhibition is related to the current strength of γ-aminobutyric acid A receptor activation. In view of this, the whole-cell patch-clamp technique was used here to record the change in muscimol activated current of dorsal root ganglion neurons in a chronic constriction injury model. Results found that damage in rat dorsal root ganglion neurons following application of muscimol caused concentration-dependent activation of current, and compared with the sham group, its current strength and γ-aminobutyric acid A receptor protein expression decreased. Immunofluorescence revealed that γ-aminobutyric acid type A receptor α2 subunit protein expression decreased and was most obvious at 12 and 15 days after modeling. Our experimental findings confirmed that the y-aminobutyric acid type A receptor α2 subunit in the chronic constriction injury model rat dorsal root ganglion was downregulated, which may be one of the reasons for the reduction of injury in dorsal root ganglion neurons following muscimol-activated currents.

Microwave-assisted Polycondensation of L-2-Hydroxy-3-phenylpropanoic Acid

Amorphous poly (L-2-hydroxy-3-phenylpropanoic acid) (PLHPPA) was synthesized by the microwave-assisted polycondensation of L-2-hydroxy-3-phenylpropanoic acid (LHPPA). The weight average molar mass (Mw) of PLHPPA ranged from 3600 to 5300 and polydispersity index (Mw/Mn) from 1.0 to 1.4 when the reaction mixture was irradiated by microwave at 255, 340 and 510 w for 1 to 10 h, respectively.

Free fatty acids, glucose, and insulin in type 2 diabetes mellitus

Xu et al used the HOMA2 model to estimate theβ-cell function and insulin resistance levels in an individual from simultaneously measured fasting plasma glucose and fasting plasma insulin levels.This method is based on the assumption that the glucose-insulin axis is central for the metabolic activities,which led to type 2 diabetes.However,significant downregulation of both the NKX2-1 gene and the TPD52L3 gene force an increase in the release of free fatty acids(FFAs)into the blood circulation,which leads to a marked reduction in membrane flexibility.These data favor a FFA-glucose-insulin axis.The authors are invited to extend their study with the introduction of the saturation index(number of carbon-carbon double bonds per 100 fatty-acyl chains),as observed in erythrocytes.

Rice Aroma: A Natural Gift Comes with Price and the Way Forward

Aromatic rice belongs to a small but important sub-group of rice,which is highly regarded for its excellent aroma and superior grain quality.Aromatic rice,especially Basmati-and Jasmine-type rice,is being traded at a high price in the local and global markets.Genetically,rice aroma is a phenotypical expression of spontaneous recessive mutations of the OsBadh2 gene(also known as fgr/badh2/osbadh2/os2AP gene).These mutations inhibit the flow ofγ-aminobutyraldehyde(GAB-ald)toγ-aminobutyric acid(GABA),and consequently,the accumulated GAB-ald is diverted to a potent flavour component 2-acetyl-1-pyrroline(2AP)by a non-enzymatic reaction with methylglyoxal.The natural incidence of non-functional osbadh2 mutation along with selection and nursing by the farmer from the ancient time makes rice aroma as a prominent natural gift.As GABA and methylglyoxal play significant roles in stress tolerance,and their biosynthesis is strictly regulated in rice plants,the accumulation of 2AP in aromatic rice depends on the interaction of various genetic and environmental factors,and its production may come at some costs of sacrificing tolerance.This review focused on some potential underlying genes in the 2AP and GABA biosynthesis pathways,and analyzed most aspects of aroma formation in rice,and summarized the molecular mechanism of aroma production together with its genetic and non-genetic influencing factors.The present review also stated approaches to produce high-quality aromatic rice via developing novel cultivars and with good agronomic knowledge-based practice.

The Influence of Aziridine on the Aging of Composite Solid Rocket Propellant

Aging of a solid composite propellant containing HTPB/AP/AL was performed in order to validate the conformance of the accelerated aging data to the Arrhenius law. The main objective of the work was to examine the influence of the aziridine bonding agents family on the propellant aging. Aging of the prepared propellant samples was conducted as follows: 1. Four samples, one free of bonding agents, and three containing aziridine based bonding agents MAPO,HX-752, MAT4 were aged at 65°C. 2. Another four samples based on HX-752, MAT4 with different curing agents were aged at 65°C. The measured mechanical properties of the free bonding agent propellant samples were very far from the specifications and this illustrates the importance of the bonding agents in both the preparation and the aging phases.The prepared bonding agent 'MAT4' gave remarkable improvements of the mechanical properties comparing with HX-752 and MAPO. The aziridine bonding agents family inhibited the rate of decomposition of the propellant during the aging periods and supported the propellant matrix against decomposition at the elevate temperatures. Using of HMDI as curing agent gave slight better mechanical properties to the IPDI.

Low temperature fabrication for high-performance semitransparent CsPbI_(2)Br perovskite solar cells

All-inorganic CsPbI_(2)Br perovskite with suitable bandgap and excellent thermal stability has been reported as the most promising candidate for efficient perovskite solar cells (PSCs). However, the high annealing temperature (> 250 ℃) and poor stability of α-CsPbI_(2)Br greatly limit the future application in photovoltaic field. Herein, a facile method is reported to prepare α-CsPbI_(2)Br perovskite film with high stability at low temperature (70 ℃) by incorporating a small amount of γ-aminobutyric acid (GABA) in the precursor solutions. The devices exhibit reproducible photovoltaic performance with a champion efficiency up to 15.16%, along with the excellent stability, maintaining more than 80% of its initial efficiency after stored in ambient condition for 600 h without any encapsulation. Most importantly, the method enables fabrication of semitransparent CsPbI_(2)Br PSCs with a PCE of 6.76%, as well as an average visible transparency (AVT) of 25.38%. To the best of our knowledge, this is the first attempt to apply CsPbI_(2)Br to the semitransparent solar cells.

Waggle needling Yanglingquan(GB34) enhances cerebral blood flow and ameliorates condition of spastic paresis in rats with middle cerebral artery occlusion induced by surgical nylon suture

OBJECTIVE:To evaluate the therapeutic efficacy and the influence on cerebral blood supply of waggle needling Yanglingquan(GB34) on spastic paresis(SP) rats after middle cerebral artery occlusion(MCAO) induced and investigate its mechanism of relieving neurobehavior deficiency.METHODS:SP rat model was produced by permanent MCAO.Rats were divided into five groups:blank control group(Control),sham operation group(Sham),model group(Model),waggle needling group(WN) and perpendicular needling group(PN).SP rats were treated with acupuncture from day 3 after MCAO,once a day for 6 d.The modified neurological severity score(m NSS) and modified Ashworth scale(MAS) were conducted on days 0,1,3,5,7 and 9.Cerebral blood flow(CBF) in ischemic cortex was measured by laser speckle imaging 5 min pre ischemia,5 min post ischemia,and after intervention on day 9.All rats were sacrificed at day 9 and the protein and m RNA expressions of γ2 subunit of the γ-aminobutyric acid receptor A(GABAAγ2) and K+-Cl-cotransporter 2(KCC2) in the ischemic cortex and lumber enlargement was measured by Western blotting and real-time quantitative polymerase chain reaction.RESULTS:Both Control and Sham groups showed no changes in m NSS and MAS scores and in the regional CBF.Compared with Model group,both WN and PN treatments significantly ameliorated neurological deficit(P < 0.01),decreased muscle tone(P < 0.05),and enhanced CBF(P < 0.001) in SP rats;moreover,WN showed superior effects than PN(P < 0.001).In line with the improvement in neurobehavior,acupuncture interventions up-regulated the expressions of GABAAγ2 and KCC2 in the ischemic cortex as well as lumber enlargement(P < 0.01) in SP rats,and those changes were more obvious in WN(P < 0.05).CONCLUSIONS:Acupuncture at Yanglingquan(GB34) enhanced cerebral blood flow and ameliorated SP in permanent MCAO rats,while waggle needling was superior to regular perpendicular needling.Waggle needling Yanglingquan(GB34) would be a potential complementary therapy for SP.

Thymosin Alpha-1 Inhibits Complete Freund’s Adjuvant-Induced Pain and Production of Microglia-Mediated Pro-inflammatory Cytokines in Spinal Cord

Activation of inflammatory responses regulates the transmission of pain pathways through an integrated network in the peripheral and central nervous systems.The immunopotentiator thymosin alpha-1(Tal)has recently been reported to have anti-inflammatory and neuroprotective functions in rodents.However,how Tα1 affects inflammatory pain remains unclear.In the present study,intraperitoneal injection of Tal attenuated complete Freund's adjuvant(CFA)-induced pain hypersensitivity,and decreased the up-regulation of pro-inflammatory cytokines(TNF-α,IL-1β,and IL-6)in inflamed skin and the spinal cord.We found that CFA-induced peripheral inflammation evoked strong microglial activation,but the effect was reversed by Tα1.Notably,Tα1 reversed the CFA-induced up-regulation of vesicular glutamate transporter(VGLUT)and down-regulated the vesicular γ-aminobutyric acid transporter(VGAT)in the spinal cord.Taken together,these results suggest that Tα1 plays a therapeutic role in inflammatory pain and in the modulation of microgliainduced pro-inflammatory cytokine production in addition to mediation of VGLUT and VGAT expression in the spinal cord.

谷氨酸系列化合物专利

L-谷氨酸-5-甲酯的合成方法L-谷氨酸-5-甲酯（L—Glutamic acid 5-methyl ester）是合成多种氨基酸和氨基酸药物的重要原料。本发明以H2SO4为催化剂，在甲醇溶剂中对谷氨酸进行酯化，酯化反应结束后，用Ba（OH）2除去催化量的H2SO4，再回收甲醇，可获得含量98％以上的L-谷氨酸-5-甲酯产品。回收的95％甲醇溶剂可再用于酯化反应。本发明的合成工艺简单易行，