S-nitrosoglutathione-containing hydrogel accelerates rat cutaneous wound repair

BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization.     

超顺磁氧化铁标记神经干细胞移植治疗帕金森病大鼠脑MRI改变的研究

目的研究应用超顺磁氧化铁（SPIO）标记神经干细胞（NSCs）移植治疗帕金森病（PD）大鼠脑部MRI的改变。方法从大鼠胚胎脑中分离培养中脑NSCs,用脂质体转染法将SPIO标记NSCs;同时制作大鼠PD模型,SPIO标记的NSCs移植到PD大鼠右侧纹状体区,分别在移植后1周、2周、4周、6周、8周和10周给大鼠行MRI检查,2周、4周、6周、8周、10周时进行旋转行为评分,并与NSCs组和对照组比较。结果脑内移植SPIO标记NSCs的PD大鼠1周后MRI检查显示在移植区呈低信号改变;移植后10周,在T2和T2梯度回波仍可观察到移植区的低信号,同时移植区有混杂信号。NSCs移植大鼠的旋转行为评分在移植后2-10周明显少于对照组（均P〈0.05）。结论SPIO标记的NSCs可以在MRI上显示其在移植大鼠脑部的分布和存活情况,有利于NSCs移植治疗PD后的疗效观察。     

芳香烃羟化酶活性与苯并[a]芘中间代谢产物生成关系的研究

100mg香烟烟油,多氯联苯诱导大鼠肝S_9组分中芳香烃羟化酶代谢B[a]P为3-OH-B[a]P的活性分别升高约40,20倍,而代谢B[a] P生成6-OXY-B [a]P自由基产物却仅由多氯联苯诱导的S_9组分作用中才被观察到。     

HSV-2W株对Vero细胞分裂指数影响的研究

HSV-2 W株感染Vero细胞后,对细胞的分裂指数可产生以下影响:在一定作用时间内,接种病毒的细胞其分裂指数高于对照细胞而低于接种秋水仙素的细胞;接种病毒最多的细胞高于接种病毒量少的细胞;但超过一定时间,则差别不显著;接种病毒时间长的细胞低于接种病毒时间短的细胞;接种灭活病毒的细胞高于接种未来灭活病毒的细胞。根据以上结果就HSV-2对宿主的某些生物学作用讲行了讨论。     

hMSH2、hMLHl在胃癌中的表达及其临床意义

目的:探讨错配修复基因hMSH2、hMLH1蛋白的表达与胃癌临床病理学特性之间的关系。方法:采用免疫组织化学方法检测40例胃癌及50例胃炎组织中hMSH2、hMLH1蛋白的表达情况,并研究其与胃癌临床病理之间的关系。结果:40例胃癌标本中,hMSH2减低表达率为35%,hMLH1蛋白降低表达率为72.5%;淋巴结转移阳性的胃癌中,hMSH2、hMLH1蛋白表达明显减低。结论:hMSH2、hMLH1蛋白可能与早期胃癌和胃癌淋巴结转移有关。     

328. Mechanismen der langzeitakzeptanz allogener rattenlebertransplantate: makrophagenaustausch und suppressorzellaktivierung

Summary After orthotopic rat liver transplantation in the fully allogeneic BN (RT-1n) to LEW (RT-11) combination, the phenomenon of spontaneous tolerance of donor antigen occurs. We demonstrate two different immune mechanisms that may account for this process. Using adoptive transfer assays we show the presence of donor-specific T-suppressor lymphocytes in the spleens of long-term surviving liver graft, recipients. These cells prolong - adoptively transferred into irradiated syngeneic hosts — the survival of donor-specific (BN) but not third-party (DA) renal allografts (I00 days vs 1I days in control groups). Secondly, we demonstrate the replacement of Kupffer cells in the graft by recipient macrophages using polymorphic monoclonal antibodies in an immunoperoxidase technique. This may contribute to graft adaptation and thus to long-term graft acceptance.     

Crystal structure and conformation of polypeptides: L-leucylglycylglycylglycine

Crystals of L-leucylglycylglycylglycine, LGGG (C₁₂H₂₂N₄O₅), grown from an ethanol-water solution, are orthorhombic, space groups P2₁2₁2₁, with unit cell dimensions (at 22 ± 3°) a = 9.337(1), b = 10.995(1), c = 15.235(1)Å, v = 1563.4 ų, Z = 4 with a density of D_obs= 1.29 g-cm^-3 and D_calc= 1.279 g°cm^-3. The crystal structure was solved by the application of direct methods and refined to an R value of 0.029 for 1018 reflections with I ± 2s?. The molecule exists as a zwitterion in the crystal. The trans peptide backbone takes up a folded conformation at the middle glycylglycyl link accompanied by a significant nonplanarity up to Δω of 8° at the middle peptide and is relatively more extended at the two ends. The molecules are linked together intermolecularly in an infinite sequence of head to tail 1–4′ hydrogen bonds, as is typical of charged peptides. It is interesting to note that while glycylglycylglycine takes up an extended β-sheet conformation, addition of Leu to the N-terminal results in a bent conformation.     

Cardiovascular regulation and lipoprotein profile during administration of co-dergocrine in essential hypertension

Summary Co-dergocrine has recently been demonstrated acutely to lower plasma norepinephrine (NE) and blood pressure (BP) in patients with essential hypertension, and similar results have been obtained during chronic administration of co-dergocrine to healthy men. The present study investigated the effect of 3 weeks of treatment with co-dergocrine 4 mg/day on BP, plasma catecholamines, certain other BP-regulating factors and serum lipoproteins in patients with essential hypertension. Compared to placebo conditions, co-dergocrine decreased supine BP and heart rate by −7% and the upright plasma NE level by −24%. Supine plasma NE also fell (−24%). Total cholesterol and the LDL + VLDL-cholesterol lipoprotein fraction were lowered by −6%. No significant change was observed in plasma renin activity, angiotensin II, aldosterone and epinephrine levels, whole blood and plasma volume, exchangeable sodium, and the cardiovascular responsiveness to NE, angiotensin II and isoproterenol. The findings suggest that in patients with essential hypertension, chronic treatment with co-dergocrine may slightly decrease sympathetic outflow and, at least in the short-term, lower the potentially atherogenic serum LDL + VLDL − cholesterol fraction.     

过氧化氢对不同时相HepG2细胞氧化作用的研究

背景与目的:研究过氧化氢(H2O2)对不同时相HepG2细胞作用的选择性,以进一步探讨H2O2:诱导肿瘤细胞凋亡的机制.材料与方法:以胸腺嘧啶核苷(TdR)阻断法获得不同细胞周期时相的同步化细胞,分别加入800 μmol/L的H2O2作用3 h,并检测各组细胞的丙二醛(MDA)含量、黄嘌呤氧化酶(XOD)和5'核苷酸酶(5'NT)的活性及抗羟自由基(抗·OH)和抗超氧阴离子自由基(抗O2)的活性.结果:经H2O2处理的各组MDA含量和XOD、抗·OH、抗O2活性显著高于对照组,其差异均具有统计学意义(P均＜0.01),5'NT活性低于对照组(P＜0.01).与未同步化组比较,同步化于S期和G2/M期的细胞MDA含量和XOD、5'NT、抗·OH和抗O2活性显著升高,其差异均具有统计学意义(P均＜0.01),而同步化于G1期的细胞MDA含量、XOD、5'NT和抗O2-活性显著降低,差异均具有统计学意义(P均＜0.01).结论:H2O2作用同步化HepG2细胞后,代谢产生自由基的酶活性,脂质过氧化产物含量以及抗氧化水平均表现出细胞周期特异性,这可能是过氧化氢对不同时相HepG2细胞损伤作用不同的原因.     

可逆性胆碱酯酶抑制剂的研究:2-氧化-1,3,2-二氧磷杂环己烷类化合物的合成

本文报道2-氧化-1,3,2-二氧磷杂环己烷类衍生物的合成,希望寻找效果较好的可逆性胆碱酯酶抑制剂。初步药理实验证明,所合成的大部分化合物具有一定的抑制乙酰胆碱酯酶的作用,且毒性较低。通过对中间体Ⅱ进行质谱分析,发现该类化合物中大部分存在M-57碎片离子峰,利用高分辨质谱和亚稳离子测定,确定了该碎片离子的生成过程。