人参培养细胞中粗多糖的提取分离及其理化特性

人参(Panax ginseng)是我国传统的珍贵药材,利用人参细胞培养方法产生人参皂甙类有用成分已有不少报道。现代医药学研究表明,人参多糖有较强的药理活性,如刺     

Evaluation of Ethanol on Gastric Epithelial Restoration in Vitro

Ethanol exerts damaging effects on gastric mucosa and delays ulcer healing. To investigate the effect of ethanol on the wound repairing process, we used a wound repair model using primary cultured gastric mucosal cells. A confluent monolayer gastric mucosal cell sheet consisting mainly of mucous cells was wounded to make a cell-free area of constant size. Cell-free area was restored with time after wounding and monitored every 12 hr using a computer image analyzer to observe epithelial cell restoration quantitatively in the presence and absence of ethanol (2.0%). It was found that, although the control wound was completely repaired in 36 to 48 hr, the group treated with 2.0% ethanol showed a significant delay of repair. In the control, 5-bromodeoxyuridine-positive cells appeared around the wound in 24 to 36 hr. In contrast, the group treated with 2.0% ethanol showed no 5-bromodeoxyuridine-positive cells during the experiment. In conclusion, 2.0% ethanol retarded the repair of gastric mucosal restoration by inhibiting the initial gastric cell migration, followed by inhibition of proliferation of cells.     

肝基质鼠尾胶对日本血吸虫培养细胞AKP和ACP影响的研究

目的 研究肝基质、鼠尾胶对日本血吸虫成虫培养细胞碱性磷酸酶(AKP)和酸性磷酸酶(ACP)活性的影响,筛选适合日本血吸虫细胞培养的基质。方法 将虫龄28d的日本血吸虫成虫细胞,接种于预先铺敷有肝基质和鼠尾胶的小盖玻片上常规培养,未铺敷基质者作对照。运用酶细胞化学方法,分别于培养5、14、21、35d对日本血吸虫成虫培养细胞进行AKP和ACP染色,显微镜下观察并拍照,图像分析仪测定其含量,并作统计分析。结果 铺敷的基质不同,培养细胞的AKP和ACP活性不同。AKP、ACP着色深浅均按对照组、鼠尾胶组、肝基质组依次加深。定量分析显示,培养14d内,肝基质组与鼠尾胶组细胞AKP活性明显高于对照组(肝基质组P<0.01;鼠尾胶组P<0.05);两基质组培养细胞之间差异也有显著性(P<0.05)。培养21d后,肝基质组细胞AKP活性分别高于鼠尾胶组和对照组(P<0.01);后两者培养细胞之间的AKP活性无明显差异(P>0.05)。培养5d细胞的ACP活性,肝基质组与鼠尾胶组明显高于对照组(P<0.05),两基质组相互比较差异无显著性(P>0.05);培养14d后,各组之间两两比较均有差异(P<0.05),肝基质组培养细胞ACP活性最强,鼠尾胶组次之,对照组最弱。结论 肝基质较为适合日本血吸虫培养细胞的存活与生长。     

Effects of insulin, dexamethasone and glucagon on the production of apolipoprotein A-I in cultured rat hepatocytes

Cultured rat hepatocytes were used to study the effects of hormones on the production of apo A-I. In addition, we compared these effects with the production of albumin. Hepatocytes were isolated from normal adult rat livers and cultured in MEM, as nearly confluent monolayers. In the absence of hormones, apo A-I and albumin accumulated in the culture medium almost linearly for periods up to 24 h. The rates of accumulation of apo A-1 and albumin in the medium were 22 ng/mg cell protein per h and 1.2 μg/mg cell protein per h, respectively. During the incubations the cellular contents of apo A-1 remained constant.

Insulin stimulated the production of albumin at concentrations over 10⁻¹⁰ M, but inhibited the production of apo A-I at concentrations over 10⁻⁸ M. Dexamethasone showed no significant effects on albumin production but stimulated apo A-1 production at concentrations over 10⁻⁶ M. Glucagon inhibited the production of albumin and apo A-I dose-dependently at concentrations over 10⁻¹⁰ M. Thus, the production of albumin and apo A-1 are presumably controlled by different regulatory mechanisms.     

The use of Biobrane as a delivery method for cultured epithelial autograft in burn patients

Background

Cultured epithelial autografts (CEA) are well described in the literature and are advantageous when dealing with major burns. There have been many methods of CEA application described, however they all have their own difficulties. Here we describe a novel technique of culturing the keratinocytes in Biobrane^®.

Methods

Skin samples were taken from three patients and cultured into pre-confluent keratinocytes. These were seeded in Biobrane^® and applied directly to the patients’ wounds.

Results

Three patients had Biobrane^® with seeded keratinocytes applied. The Biobrane was applied to both donor and burn wound sites, with healing times being similar to the keratinocyte sheets.

Conclusion

The experience of the authors shows that using Biobrane^® seeded with keratinocytes was easier to handle and quicker to produce than confluent sheets of keratinocytes, with no perceived disadvantages to the patients.     

Organ-cultured chick embryonic hearts of various ages. I. Electrophysiology

Tetrodotoxin (TTX)-insensitive slow Na⁺ channels are converted or replaced by TTX-sensitive fast Na⁺ channels during normal embryonic development of the chick heart, and rapid reversion occurs in monolayer cell culture (denervated). Fast Na⁺ channels first appear at 4 to 5 days, which is about the time of innervation. Studies were done to determine whether changes in cation channels will occur while hearts are in organ culture. To test whether fast Na⁺ channels will develop in the absence of innervation, hearts from chick embryos 2 to 3 days old were placed into culture for 6 to 8 days. Although the resting potentials of the ventricular cells were about the same as those obtained from fresh 8 to 10 day old hearts, the maximum rate of rise of the action potentials ($\text{+}\text{V}\text{?}{}_{\mathrm{<mtext>max</mtext>}}$) did not reach the high value (about 80 V/s) expected from the calendar age. Instead $\text{+}\text{V}\text{?}{}_{\mathrm{<mtext>max</mtext>}}$ remained at about the same value (12 V/s) that the hearts had when placed into culture. The action potentials were completely insensitive to TTX. The slow channels admit primarily Na⁺ and not Ca²⁺ because Mn²⁺ (1 mm) and lowering [Ca²⁺]₀ to nearly zero by EGTA did not diminish $\text{+}\text{V}\text{?}{}_{\mathrm{<mtext>max</mtext>}}$. To test whether the fast Na⁺ channels disappear in organ culture, hearts from embryos 15 to 19 days old were cultured as whole hearts or minced hearts. The whole hearts survived well for 1 to 6 days; the $\text{+}\text{V}\text{?}{}_{\mathrm{<mtext>max</mtext>}}$ values remained high (～ 100 V/s), and TTX completely blocked the action potentials. The minced hearts had variable $\text{+}\text{V}\text{?}{}_{\mathrm{<mtext>max</mtext>}}$ values, depending on the piece. Those pieces which had a low $\text{+}\text{V}\text{?}{}_{\mathrm{<mtext>max</mtext>}}$ were insensitive to TTX, and those which had a high or intermediate $\text{+}\text{V}\text{?}{}_{\mathrm{<mtext>max</mtext>}}$, were reduced to 5 to 20 V/s by TTX; these persisting responses in TTX were not blocked by Mn²⁺ or zero [Ca²⁺]₀. The results suggest that, while in organ culture, young hearts do not gain fast Na⁺ channels or lose the slow Na⁺ channels that would normally occur in situ. Organ-cultured old hearts left intact do not lose their fast Na⁺ channels. Thus, young or old hearts retain the channels that they originally possessed when placed into culture. Mincing initiates a gain of slow Na⁺ channels, and in some pieces, a partial loss of fast Na⁺ channels.     

NADPH氧化酶对培养的小鼠血管平滑肌细胞Toll样受体4介导的炎症表型的影响

目的 探讨NADPH氧化酶对培养的小鼠血管平滑肌细胞(vascular smooth muscle cell,VSMC)Toll样受体4(Toll-like receptor 4,TLR4)介导的炎症表型中的作用.方法 分别采用NADPH氧化酶激动剂血小板衍生生长因子-BB(platelet-derived growth factor-BB,PDGF-BB)和抑制剂夹竹桃麻素(apocynin)处理培养的C57BL/6J和TLR4-/-小鼠胸主动脉VSMC.分别采用荧光探针二氯荧光素双醋酸盐染色法检测VSMC内活性氧(reactive oxygen species,ROS)含量,酶联免疫吸附法检测VSMC白细胞介素(interleukin,IL)-6、IL-1β和肿瘤坏死因子-α(tumor necrosis factor-o,TNF-α)表达,四甲基偶氮唑蓝染色法和Boyden小室检测VSMC的增殖和迁移.结果 PDGF-BB处理可显著增高C57BL/6J和TLR4-/-VSMC内ROS含量,而夹竹桃麻素可抑制ROS生成.PDGF-BB处理可使C57BL/6J VSMC IL-6[(52.69±3.49)ng/ml对(35.04±2.74) ng/ml,P=0.001]、IL-1β[(79.68±2.33) ng/ml对(62.38±0.54)ng/ml,P=0.000]和TNF-α[(218.35±5.42)ng/ml对(124.74±4.59) ng/ml,P=0.000]表达显著上调,增殖(1.69±0.53对1.04±0.40,P=0.000)和迁移(42.ll±4.05对1.69±0.53,P=0.000)能力均显著增强,而夹竹桃麻素预处理则可显著抑制VSMC IL-6[(42.11±4.05) ng/ml对(52.69±3.49) ng/ml,P=0.010]、IL-1β[(67.57± 1.36)ng/ml对(79.68±2.33) ng/ml,P=0.000]和TNF-α[(156.18±6.98) ng/ml对(218.35±5.42) ng/ml,P=0.000]表达以及增殖(1.23±0.42对1.69± 0.53,P=0.000)和迁移(42.11±4.05对52.69±3.49,P=0.000).TLR4-/-VSMC经PDGF-BB和夹竹桃麻素处理后,IL-6、IL-1β和TNF-α表达以及增殖和迁移能力均无显著变化.结论 NADPH氧化酶衍生的ROS参与了TLR4介导的VSMC炎症表型以及增殖和迁移,可能是其影响动脉粥样硬化发生和发展的重要机制.     

L’ingénierie cutanée pour le traitement des brûlures graves

Severe burned patients need definitive and efficient wound coverage. Outcome of massive burns has been improved by using cultured epithelial autografts (CEA). Despite fragility, percentages of success take, cost of treatment and long-term tendency to contracture, this surgical technique has been developed in few burn centres. First improvements were to combine CEA and dermis-like substitute. Cultured skin substitutes provide earlier skin closure and satisfying functional result. These methods have been used successfully in massive burns. Second improvement was to allow skin regeneration by using epidermal stem cells. Stem cells have capacity to differentiate into keratinocytes, to promote wound repair and to regenerate skin appendages. Human mesenchymal stem cells contribute to wound healing and were evaluated in cutaneous radiation syndrome. Skin regeneration and tissue engineering methods remain a complex challenge and offer the possibility of new treatment for injured and burned patients.