改性壳聚糖基导电复合材料神经导管的体内降解及组织相容性观察

目的探讨改性壳聚糖基导电复合材料神经导管的体内降解及组织相容性，以期为组织工程神经构建提供新的支架材料。方法采用微乳液聚合法合成纳米聚吡咯（polypyrrole，PPy），与壳聚糖共混后注入定制的成管模型，冷冻干燥及脱酸后，制成改性纳米 PPy/壳聚糖复合材料导管（记作 CP 导管）；再经不同程度乙酰化（乙酰化反应时间分别为 30、60、90 min）改性，制备不同乙酰度的 CP 导管（记作 CAP1、CAP2、CAP3 导管）。各导管予红外光谱、扫描电镜进行表征，使用四探针电导仪测定电导率。取 30 只雌性 SD 大鼠，于背部左、右侧各制备 4 个皮下筋膜隧道，分别植入上述导管。术后 2、4、6、8、10、12 周取材，大体观察导管形态及完整性、扫描电镜观察导管微观结构、测量导管降解率，以观察导管体内降解性能；行 HE 染色及抗巨噬细胞免疫荧光染色，观察导管体内组织相容性。结果经表征证实乙酰化改性后的各导管 1 562 cm^–1左右的酰胺Ⅱ谱带增强，表示壳聚糖乙酰化改性成功。各导管均具备导电性能，组间电导率差异无统计学意义（P>0.05）。扫描电镜观察示各导管表面相对光滑、结构致密，无明显差异。导管植入体内后，随时间延长均出现一定程度塌陷，其中 CAP3 导管尤为明显；亦出现不同程度质量丢失，且乙酰化度越高，质量变化越大（P<0.05）。扫描电镜观察示植入 12 周后材料出现较多孔隙，且随着乙酰化度增加，孔隙呈增大趋势。组织学观察显示术后早期各导管均有较多巨噬细胞、淋巴细胞浸润，随着植入时间延长，淋巴细胞有所减少、成纤维细胞增多、胶原纤维增生明显。 结论不同乙酰度的改性壳聚糖基导电复合材料神经导管均有较好的体内生物相容性、可导电、可降解，且降解性与乙酰度相关，有望为组织工程神经构建提供一种新的支架材料。     

卡氏乳香中1个新的降二萜

目的 研究卡氏乳香Boswellia carterii中的化学成分及其抗骨质疏松活性。方法 运用硅胶柱色谱、ODS柱色谱和制备高效液相色谱等方法进行化学成分分离,通过波谱数据及文献对比对其进行结构解析。结果 卡氏乳香的95%乙醇提取物中分离得到11个化合物,分别鉴定为 (1R,2E,8S,9R)-1,9-环氧-8-乙酰氧基-4,5-二氧代降西松烷型-2-烯（1）、rel(1S,3R,7E,11S,12R)-1,12-epoxy-4-methylenecembr-7-ene-3,11-diol（2）、boscartin F（3）、boscartene K（4）、fidmansumbin-13(17)-en-3,16-diene（5）、3α-acetoxyl-7-oxo-tirucalla-8,24-dien-21-oic acid（6）、boscartene N（7）、3β-hydroxy-tirucallic acid（8）、α-boswellic acid（9）、boscarterol O（10）、boscarterol F（11）。结论 化合物1是新化合物,命名为卡氏乳香素,化合物5为首次从乳香中分离得到,化合物2和10首次从该属植物中分离得到。对11个化合物进行抗骨质疏松活性筛选,发现化合物1、3、6和10具有良好的抑制破骨细胞活性。     

An Oil-in-Water adjuvant significantly increased influenza A/H7N9 split virus Vaccine-Induced circulating follicular helper T (cTFH) cells and antibody responses

BackgroundUnadjuvanted A/H7N9 vaccines are poorly immunogenic. The immune response is improved with the addition of MF59, an oil-in-water adjuvant. However, the cellular immunologic responses of MF59-adjuvanted A/H7N9 vaccine are not fully understood.Methods37 participants were vaccinated with 2 doses of 2013 influenza A/H7N9 vaccine (at Days 1 and 21) with or without MF59 and enrolled in an immunology substudy. Responses were assessed at multiple timepoints (Days 0, 8, 21, 29, and 42) for hemagglutination inhibition (HAI) and neutralizing antibody (Neut) assays, memory B cell responses by enzyme-linked ImmunoSpot; circulating follicular helper T cells (cT_FH) and CD4 + T cells by intracellular cytokine staining.ResultsMF59-adjuvanted influenza A/H7N9 vaccine induced significantly higher hemagglutination inhibition (HAI) and neutralizing antibody (Neut) responses when compared to unadjuvanted vaccine. The adjuvanted vaccine elicited significantly higher levels of Inducible T-cell Co-Stimulator (ICOS) expression by CXCR3⁺CXCR5⁺CD4⁺ cT_FH cells, compared to unadjuvanted vaccine. The magnitude of increase in cT_FH cells (from baseline to Day 8) and in IL-21 expressing CD154⁺CD4⁺ T cells (from baseline to Days 8 and 21) correlated with HAI (at Day 29) and Neut antibody (at Days 8 and 29) titers. The increase in frequency of IL-21 expressing CD154⁺CD4⁺T cells (from baseline to Day 21) correlated with memory B cell frequency (at Day 42).ConclusioncT_FH activation is associated with HAI and Neut responses in recipients of MF59-adjuvanted influenza A/H7N9 vaccine relative to unadjuvanted vaccine. Future studies should focus on optimizing the cT_FH response and use cT_FH as an early biomarker of serological response to vaccination.This trial was registered at clinicaltrials.gov, trial number NCT01938742.     

Some Actions of 9-Amino-1,2,3,4-Tetrahydroacridine (THA) on Cholinergic Transmission and Membrane Currents in Rat Sympathetic Ganglia

THA (Tacrine) is an anticholinesterase drug reported to alleviate cognitive deficit in Alzheimer's disease. We have used rat isolated superior cervical sympathetic ganglia as a model mammalian cholinergic neural system to study effects of THA on cholinergic synaptic transmission and postsynaptic membrane currents. At 0.1 - 3 microM, THA augmented the postsynaptic depolarizations and inward clamp currents produced by acetylcholine but not by the cholinesterase-resistant analogue, DMPP. Higher concentrations depressed these responses to both acetylcholine and DMPP, and reduced the acetylcholine-induced increase in membrane current noise. At 1 microM, THA did not affect the amplitude or time-course of fast (nicotinic) excitatory postsynaptic currents (epscs) evoked by single orthodromic volleys, but higher concentrations induced a biphasic epsc decay. In contrast, low concentrations of THA (1 - 3 microM) greatly augmented and prolonged the muscarinic slow epsc evoked by repetitive orthodromic volleys: this effect was blocked by 1 microM atropine. Concentrations above 0.1 mM produced a membrane depolarization and inhibited a variety of membrane ionic currents, including voltage-gated Ca current and subsequent Ca-activated K currents, and voltage-gated M- and A-type K currents. It is concluded that the principal effect of THA is to inhibit cholinesterase, and that the main consequence of this is to augment and prolong the muscarinic slow epsc. In contrast, the nicotinic fast epsc is not increased but instead may be reduced through a nicotinic channel-blocking action. Although THA could also block several other ion channels the concentrations required were too high to contribute significantly to its principal pharmacological actions on ganglionic transmission.     

大鼠卵泡发育过程中基质金属蛋白酶-2，-9的作用

目的：探讨基质金属蛋白酶-2,-9（MMP-2,-9）在大鼠卵泡发育的组织重建中的作用。方法：采用原位杂方法检测动情周期大鼠卵泡中MMP-2,-9mRNAs的基因表达变化,并通过密度扫描方法对原位杂交结果进行半定量分析。结果：在动情周期中,各情期卵巢中卵泡的颗粒细胞和发育良好的卵泡的膜细胞中均可检测到MMP-2m-RNA的杂交信号;MMP-9mRNA的表达始于已发育良好的窦前卵泡的膜细胞,此后在小窦状卵泡、窦状卵泡及排卵前卵泡的膜细胞中均检测到MMP-9mRNA的杂交信号。结论：MMP-2,-9可能通过其基因的表达变化参与卵泡的发育过程。     

杂多化合物九钨三钛硅酸盐致畸毒性研究

目的 :观察九钨三钛硅酸盐 ( α- K8H2 〔Si W9Ti3 O4 0 〕· 1 5H2 O,简称 α- Ti3 )孕期给药对大鼠胎仔的毒性影响。方法 :大鼠孕期以 57.0 9,1 71 .2 8和 51 3.83mg/ kg剂量经口给予α- Ti3 ,并以Vit A为阳性对照及蒸馏水为阴性对照 ,产前剖腹检测胎鼠生长发育指标、外观内脏骨骼形态等。结果 :三个剂量组均未见胎鼠外观、内脏及骨骼畸形。低剂量组与高剂量组的活胎率升高 ,吸收胎数下降 ,与阴性对照组比较有显著性差异 (均为 P<0 .0 5)。低、中、高剂量组的胎鼠体重和身长高于阴性对照组 (分别为 P<0 .0 5,P<0 .0 1 ,P<0 .0 1 ) ,且增长程度与剂量呈正相关 ( r=0 .840 8,0 .72 2 8,P<0 .0 0 5,0 .0 5)。低、中、高三个剂量组的上枕骨骨化程度及胸骨块数高于阴性对照组和阳性对照组 ( P<0 .0 5,0 .0 1 ,0 .0 1 ,0 .0 5和 P<0 .0 5,0 .0 1 ,0 .0 1 )。各剂量组的母鼠肝脏重量及肝体比值不同程度下降。其中 ,中、高剂量组及阳性对照组的肝重及肝体比值与阴性对照组比较差异显著 (肝重比较分别为 P<0 .0 5,P<0 .0 5和 P<0 .0 1 ,肝体比值比较均为 P<0 .0 5)。结论 :α- Ti3 致畸试验未见胎鼠畸形 ,但可提高胎鼠生长发育指标和骨骼骨化程度。     

东亚钳蝎毒BmK-9-(2)对豚鼠心室肌细胞钠通道的影响

目的 :观察东亚钳蝎毒 Bm K- 9- (2 )对豚鼠心室肌细胞钠通道的作用。方法 :采用全细胞膜片钳方法。结果 :Bm K- 9- (2 )使钠通道峰值电流增加 2 7%。峰值钠电导增加 1 7%。钠通道未失活成分增加 8%。 Bm K- 9- (2 )对心肌细胞钙通道没有明显影响。结论 :Bm K- 9- (2 )可激活钠通道并使钠通道失活过程延长     

Purification of the NADH reductase component of the steroid 9α-hydroxylase fromMycobacterium fortuitum

The NADH reductase component of the steroid 9α-hydroxylase fromMycobacterium fortuitum was purified to homogeneity. Recovery of the enzyme from the 50≈60% ammonium sulfate saturated fraction was 49%, with a purification factor of 100-fold. The NADH reductase has a relative molecular mass of 60 KDa as determined by SDS-PAGE. The absorption maxima at 410 and 450 nm indicate the presence of iron-sulfur group and flavin. These prosthetic groups seemed to function as redox groups that transfer electrons from NADH to the following protein. The K_M value for NADH as substrate was 68 μM. The NH₂-terminal amino acid sequence of the reductase was determined as Met-Asp-Ala-Ile-Thr-Asn-Val-Pro-Leu-Pro-Ala-Asn-Glu-Pro-Val-His-Asp-Tyr-Ala-Thr. This sequence does not show a homology with the NH₂-terminal sequences reported for the reductase component of other monooxygenases, suggesting that the NADH reductase component of the steroid 9α-hydroxylase system is novel.