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21.
AIM: To observe the effects of some component of Chinese herbs for external use on proliferation of human umbilical vein endothelial cells (HUVEC) and investigate the mechanism of promoting tissue repair. METHODS: The method of MTT was used to examine the effects of Rg1, Rh1, perlolyrine, cinnamyl aldehyde, muscone, astragaluspolysaccharin (APS), velver antler polypeptide (VAP) and soluble extract of boswellia carterii birdw (BCB) on proliferation of HUVEC. RESULTS: APS did not promote proliferation of HUVEC at 9.75 mg/L-2.5 g/L; Rh1 promoted proliferation of HUVEC at 1.94 mg/L-0.5 g/L (P<0.05 or P<0.01), and Rg1 inhibited proliferation of HUVEC at 31 mg/L (P<0.05); VAP promoted proliferation of HUVEC at 1 mg/L-0.5 g/L with optimal dose of 10 mg/L (P<0.01), Cinnamyl aldehyde promoted proliferation of HUVEC at 2 g/L(P<0. 05); Muscone and soluble extract of BCB inhibited proliferation of HUVEC at 1 g/L, 0.5-2.5 kg/L(P<0. 01), respectively; Perlolyrine inhibited proliferation of HUVEC at 0.125 g/L-0.5 g/L(P<0. 01). CONCLUSION: The external herbs for supplementing Qi and warming Yang can promote HUVEC proliferation and improve angiogenesis during tissue repair. The external herbs for promoting blood circulation and accelerating capillary movement may have influence upon other stages of tissue repair.  相似文献   
22.
Oncosis is another form of cell death, which is different from apoptosis. The review will discuss the recent advances of oncosis on pathological morphology, nuclear biochemical changes and molecular mechanisms.  相似文献   
23.
24.
ABSTRACT

1. Enzymes have been used commercially for nearly 40 years and save significant costs through sparing of expensive nutrients but the mechanism by which this is achieved is still debated.

2. The research focused on non-starch polysaccharidase (NSPase) enzymes is used as an example of where greater progress could have been made if the details of the work had been described more fully and the analysis of the data generated had been broader in scope and more critical.

3. Lack of standardisation of the details presented in the materials and methods has been identified as a significant barrier to meaningful retrospective analysis and thus limits advances in the understanding of the mode of action of these enzymes.

4. The identity of the enzyme employed and its activity is often lacking, and more importantly the purity is rarely disclosed. Contaminant activities which are neither listed nor assayed could play a significant role in the responses observed.

5. The dose optimum of most enzymes is often considerably higher than that employed in most studies. Thus studies claiming synergy between two ‘activities’ should ensure that the response is not related to each enzyme simply augmenting the dose of just one activity in the finished feed. This is a common problem, and coupled with the lack of factorial experiments to justify the presence of each enzyme in a multi-enzyme product, it is not surprising that there is still debate as to whether single or multi-enzymes are best suited poultry rations.

6. The three proposed mechanisms for NSPases (viscosity, cell wall and prebiotic) are discussed, and along with their strengths and weaknesses it is suggested that a re-evaluation of each is needed. Viscosity may have to be re-evaluated as being a function not only of the cereal being fed, but of the age of the animal as well. The cell wall theory as described is poorly modelled in vitro and hence the validity of these data is questioned. The prebiotic theory may need significant modification as it appears that the quantities of oligomers produced are insufficient to generate the additional volatile fatty acids (VFA)’s reported. It is likely that all three mechanisms play a role in the responses observed, but the prebiotic mechanism probably plays by far the most important part in low viscosity diets.

7. Future research would be improved if it considered all potential mechanisms when designing a trial. Significant failings are apparent as a result of adherence to tenets in explanation of the results. Most importantly, it should be emphasised that a hypothesis is there to be tested, not defended.  相似文献   
25.
Diabetes is characterized by an absolute or relative deficiency in β-cell mass, which cannot be reversed with existing therapeutic strategies. The restoration of the endogenous islet β-cells can stabilize the level of blood glucose. The islet β-cells can be obtained from the directional differentiation of stem cells, but the process is complex and has the risk of teratomas generation. Cell direct reprogramming, one terminal differentiated cell can transdifferentiate into another kind of terminal differentiated cell, which is other than directional differentiation from stem cells. Direct reprogramming gives rise to the generation of islet β-cells from one terminal differentiated cell, may be preferable for diabetes therapy because of its unique advantage.  相似文献   
26.
miR-let-7a在动物细胞的分化、增殖与凋亡等方面发挥越来越重要的作用。甲状腺激素(TH)作用非常广泛,机体的每个细胞几乎都是TH作用的靶细胞,其可以促进组织分化、生长和成熟。本实验用甲状腺素(T4)浓度分别为(0、0.02、0.03、0.05、0.075、0.1、0.2μmol/L)在体外培养猪的小肠上皮细胞。结果表明:T4处理组的细胞体积形态相对于空白对照组没有明显变化;当T4添加浓度为0.03μmol/L时,细胞的增殖率显著低于其他组(P0.05);当T4浓度为0~0.03μmol/L时,let-7a的表达随着添加剂量的增加而升高,浓度从0.03~0.2μmol/L变化时,let-7a的表达呈现降低趋势,浓度为0.03μmol/L时表达量极显著高于其他组(P0.01)。let-7a的表达量与细胞增殖呈负相关。  相似文献   
27.
The intestinal epithelial cells reside in close proximity to myofibroblasts and microbiota, which are supposed to have an impact on intestinal stem cells fate and to influence processes of tissue maturation and regeneration. Mechanism underlying these phenomena and their diversity among vertebrates can be studied in 3D organoid cultures. We investigated the growth of chicken embryo intestinal epithelial organoids in Matrigel with and without Toll-like receptors (TLRs) stimulation. The organoid cultures contained also some myofibroblasts with potential to promote intestinal stem cell survival. Organoid cells, expressing TLR4, TLR2 type 1 and TLR2 type 2 were incubated with their agonists (lipopolysaccharide – LPS and Pam3CSK4) or co-cultured with Lactobacillus acidophilus bacteria (LA-5). Pam3CSK4 and LA-5 promoted organoid growth, which was demonstrated by comparing the morphological parameters (mean number and area of organoids). The profile of prostaglandins (PG), known to promote intestinal regeneration, in supernatants from organoid and fibroblast cultures were evaluated. Both PGE2 and PGD2 were detected. As compared to unstimulated controls, supernatants from the Pam3CSK4-stimulated organoids contained twice as much of PGE2 and PGD2. The changes in production of prostaglandins and the support of epithelial cell growth by myofibroblasts are factors potentially responsible for stimulatory effect of TLR2 activation.  相似文献   
28.
Osteoarticular equine disease is a common cause of malady; in general, its therapy is supported on steroids and nonsteroidal anti-inflammatories. Nevertheless, many side effects may develop when these drugs are administered. Nowadays, the use of new alternatives for this pathology attention is demanded; in that sense, cannabinoid CB2 agonists may represent a novel alternative. Cannabinoid belongs to a group of molecules known by their psychoactive properties; they are synthetized by the Cannabis sativa plant, better known as marijuana. The aim of this study was to contribute to understand the pharmacology of cannabinoid CB2 receptors and its potential utilization on equine veterinary patients with a chronic degenerative painful condition. In animals, two main receptors for cannabinoids are recognized, the cannabinoid receptor type 1 and the cannabinoid receptor type 2. Once they are activated, both receptors exert a wide range of physiological responses, as nociception modulation. Recently, it has been proposed the use of synthetic cannabinoid type 2 receptor agonists; those receptors looks to confer antinociceptive properties but without the undesired psychoactive side effects; for that reason, veterinary patients, whit chronical degenerative diseases as osteoarthritis may alleviate one of the most common symptom, the pain, which in some cases for several reasons, as patient individualities, or side effects produced for more conventional treatments cannot be attended in the best way.  相似文献   
29.
The present study was aimed to explore the potential role of Toll-like receptors (TLRs) on the mink immunity, and accumulate alternative genetic material for the mink breeding for disease-resistant.Four pairs of primers were designed according to ferret TLR sequences in GenBank to obtain the sequences of TLR genes (TLR4, TLR6, TLR7 and TLR8) of mink and then performed bioinformatics analysis of these sequences.In addition, the expression of TLR4 and TLR7 genes in various tissues in young and adult minks were analyzed by RT-PCR. Sequence homology analysis showed that mink had higher homology with carnivora (ferrets, polar bear, panda, walrus, seals, dog, tiger and cat) which had the nearest perimeter in the phylogenetic tree.Tissue expression analysis showed that TLR4 and TLR7 were widely and differently expressed in variety tissues of mink.Interestingly, the expression of TLR4 and TLR7 in young mink were much higher than that in adult mink.  相似文献   
30.
胎盘免疫调节因子(placenta immunoregulating factor,PF)是从胎盘提取的小分子多肽,对病毒性疾病、免疫缺陷疾病及恶性肿瘤等具有潜在的临床应用价值.为检测牛(Bos taurus)和绵羊(Ovis aries)胎盘免疫调节因对人(Homo sapiens)胰腺癌细胞(pancreatic cancer cells-Ⅰ,PANC-Ⅰ)增殖与迁移的影响,本研究对从屠宰场获得的牛和绵羊胎盘进行分离,利用双酶水解法制备PF,将质量浓度为100~2 000 ng/mL的牛、羊PF作用于体外培养的PANC-Ⅰ细胞,以3-(4,5-二甲基噻唑-2-基)-5-(3-羧甲酯基)-2-(4-磺苯基)-2H-四唑(3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium,MTS)法观察细胞增殖抑制率,应用流式细胞技术检测其对PANC-Ⅰ细胞周期的影响.并利用Transwell迁移实验检测添加PF对PANC-Ⅰ细胞迁移能力的影响,同时通过实时荧光定量PCR法检测肿瘤抑制基因(tumor suppressor gene,PS3)和细胞周期依赖性蛋白激酶抑制因子1A基因(cyclin-dependent kinaseinhibitor 1A,P21)的表达情况.结果显示,17.11 g绵羊胎盘制得0.588 mg PF,6.61 g牛胎盘制得0.312 mgPF,胎盘质量与所得PF的质量比约为20 000∶1.在体外培养的PANC-Ⅰ细胞培养液中添加PF,从形态上观察,牛羊PF对PANC-Ⅰ细胞没有明显的影响.绵羊PF处理后PANC-Ⅰ细胞增殖抑制率为9.75%~22.89%,牛PF处理后PANC-Ⅰ细胞增殖抑制率为-3.81%~23.56%,增殖抑制率最显著的绵羊PF浓度为500 ng/mL,牛PF浓度为1 000 ng/mL.绵羊PF在浓度为500 ng/mL时,PANC-Ⅰ细胞的PI和SPF最低,而牛PF各浓度下的胰腺癌细胞增殖指数(proliferation index,PI)和增殖活性(S-phase fraction,SPF)没有明显的变化.同时,牛羊PF对PANC-Ⅰ细胞的迁移能力无显著影响.牛羊PF使PANC-Ⅰ细胞P53表达上调而P21表达下调.上述结果表明,在一定浓度下,PF对体外培养的PANC-Ⅰ细胞增殖有负调控作用,且牛羊胎盘免疫调节因子对胰腺癌细胞的影响不同,可能因为其存在的活性成分有区别.本研究为胰腺癌的治疗提供了新的思路.  相似文献   
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