Studies on the Mechanism of Aging of Distilled Liquors

Since the aging process of distilled liquors is regarded as the result of extraction of phenolic components from wooden barrel, the authors carried out the fractionation of the alcohol extract of oak wooden chips and examined the effect of the resultant fraction on whisky or brandy.

A top fraction which was obtained by means of the method of silicic acid column chromatography developed a similar flavor to the aging flavor of distilled liquors when it was warmed with raw distilled liquor. The fraction contained phenolic components such as syringic and vanillic acidlike substances and unknown polyphenolic compounds. The authors suggested that these substances in the top fraction are concerned with the development of aging flavor. On the other hand, gallic acid was found from the other fraction.     

衰老机制研究进展

回顾了衰老机制研究发展的主要理论,包括:基因控制理论中的程序性衰老理论;基因组的不稳定性与衰老相关基因的表达;蛋白质与衰老关系中的错误灾变理论;蛋白质在衰老过程中的变化;多基因控制的进化理论;衰老的神经内分泌理论;衰老的免疫理论;生活速率理论;生殖与老化;氧化应激假设。介绍了利用SAM小鼠为动物模型进行衰老机制研究的进展。     

生物体发育过程中细胞膜电位变化与衰老

维持一定的跨质膜电势,关乎到细胞内外物质交换的基本代谢能否顺利进行,因此是所有细胞生存的前提。这是生物的单细胞祖先发展出的有效生存手段,当进化到多细胞生物体后却遇到麻烦。多细胞生物为细胞营群居生活,在物理导体的静电荷分布规律的支配下,个体细胞所携外正内负的净电荷有向细胞集团边缘汇集的趋势,导致多数细胞失去本身所携净电荷,不能维持正常跨膜电势,从而逐渐失去活力。这可能就是多细胞生物衰老的根本原因。衰老是生物体在发育中随细胞数量增多不可避免的自然发生的效应。有证据显示以上描述的电荷分布变化过程的假说是真实存在。植物体中细胞所携电荷的汇集,以及随之发生的带电离子从高浓度区向低浓度区的扩散流失,可导致产生有趣的植物生电的现象,例如大树发电。对植物电压、电的极性、高密度电荷位点分布的测结果与此假说理论完全吻合。     

Studies on the Mechanism of Interferon Action

Interferon does not inactivate viruses or viral RNA. Virus growth is inhibited in interferon-treated cells, but apart from conferring resistance to virus growth, no other effect of interferon on cells has been definitely shown to take place. Interferon binds to cells even in the cold, but a period of incubation at 37°C is required for development of antiviral activity. Cytoplasmic uptake of interferon has not been unequivocally demonstrated. Studies with antimetabolites indicate that the antiviral action of interferon requires host RNA and protein synthesis. Experiments with 2-mercapto-1(β-4-pyridethyl) benzimidazole (MPB) suggest that an additional step is required between the binding and the synthesis of macromolecules. Interferon does not affect the adsorption, penetration, or uncoating of RNA or DNA viruses, but viral RNA synthesis is inhibited in cells infected with RNA viruses. The main action of interferon appears to be the inhibition of the translation of virus genetic information probably by inhibiting the initiation of virus protein synthesis.     

Studies on the Mechanism of Activation of Pepsinogen

Experiments were carried out on the effects of substrate or competitive inhibitor on the rate of appearance of N-terminal isoleucine residue of pepsin and peptides released from pepsinogen in its conversion to pepsin. Assumptions were made from these experiments, that an active site is initially formed in pepsinogen by acidification of its solution, and that peptide bond between 41-glutamyl and 42-isoleucyl residues locates in the juxtaposition to the active site forming an intramolecular enzyme-substrate complex. Thus, N-terminal tail of pepsinogen is released by a hydrolysis catalyzed by its own active site.

It was Indeed ascertained in this study that neither a small amount of pepsin which could be accompanied by pepsinogen preparation used contributes to the initial step of hydrolysis of pepsinogen nor pepsin formed accelerates the following activation process.

Therefore, it was concluded that the conversion of pepsinogen to pepsin is self-degrad-ation process.     

Studies on the Mechanism of Activation of Pepsinogen

The mechanism of activation of pepsinogen was studied. It was found that no peptide bond cleavage occurred in the molecule of denatured pepsinogen at pH 2. It was inferred from this that a specific secondary and tertiary structure is formed in the molecule of pepsinogen in acid and that it might be necessary for the hydrolysis of the peptide bond. From the circular dichroism studies on pepsinogen and pepsin, it was found that there is a conformational change in the molecule of pepsinogen at pH 4.3~4.5 and that this change is followed by a gradual formation of pepsin.     

Histochemical and Autoradiographic Studies on the Effects of Aging on the Mucopolysaccharides of the Periosteum

An autoradiographic study was made using S³⁵-sulfate for the localization, distribution, and variation in the mucopolysaccharide content of the femoral periosteum of rats from birth to old age. The mucopolysaccharides were also studied histochemically, using toluidine blue O, Rinehart and Abu'l-Haj's colloidal iron method, and the periodic acid-Schiff reaction, before and after hyaluronidase treatment. Autoradiograms revealed the uptake of S³⁵ particularly in the vicinity of the preosseous zone and adjacent osteoblasts. This labelling was highest at the period of rapid bone growth. With increasing age, the S³⁵ uptake became progressively less. The preosseous zone showed γ-metachromatic staining at all ages after treatment with toluidine blue. Active osteoblasts were mostly orthochromatic, however, β-metachromasia was exhibited at a later age. Abundant amounts of intra- and extracellular mucopolysaccharides of both the acid and neutral type were demonstrated in the periosteum. S³⁵ uptake and γ-metachromasia show the presence of sulfated mucopolysaccharides, of which chondroitin sulfate predominates in the preosseous zone. Since S³⁵ uptake is high in active osteoblasts, the inability to demonstrate metachromasia in osteoblasts may indicate either that chondroitin sulfate is liberated as fast as it is being produced, or that it may be present within the cells in a precursor form not detectable by histochemical methods.     

Studies on the Flowering Mechanism in Lemna

The dark reaction of the short day plant Lemna perpusilla was investigated. It was found that 3-phosphoglycerate and pyruvate (10^?6M) increased the flowering rate in the presence of nitrates. Pyruvate-2-¹⁴C was added to the culture solution during two hours of the dark reaction and ¹⁴C was incorporated into serine, aspartate and glutamate. It was postulated that pyruvate reacted with a nitrogen source forming an intermediate, possibly aspartate, which was further converted into serine. L. perpusilla failed to flower when the dark period was interrupted with red light and as a result endogenous serine accumulated in a high concentration. The dark reaction of L. perpusilla, in which serine was involved, required (1) oxygen, (2) ATP, (3) moderate temperature, and (4) an enzyme system.     

Studies on the Mechanism of Mold Protease Production

The activating factors of the inactive protease in cell-free extracts obtained from growing mycelia of Aspergillus sojae KS were studied. It was found that the several kinds of metals were involved in activation, and the role of these metals on the activation was investigated. The velocity of the activation was maximal around pH 10 as well as around pH 5. It was proved that a kinase (enzyme) capable of activating the inactive protease in alkaline solution does exist in the cell-free extract.     

Studies on the Mechanism of Mold Protease Production

Inactive protease in the cell free extracts obtained from growing cells of Aspergillus sojae KS was collected in a supernatant of ultracentrifugation at 14×l0⁴ g, and in fractions obtained by acetone of 35~50 per cent and by ammonium sulfate of 0.5~0.6 saturation.

The inactive protease has the same resistance against pH or heat treatments as active protease has. The activation of the inactive protease was maximal between pH 5~6, and was accelerated by several kinds of protease, and was not affected by thioglycollate and KCN.     

Studies on the Oxidation Mechanism of Vitamin E

α-Tocopherol model compound, 2,2,5,7,8-pentamethyl-6-hydroxychroman was oxidized under oxygen bubbling. Four oxidation products of 2-(γ,γ-dimethylallyl)-3,5,6-trimethyl-1,4-benzoquinone (B), 2,2,7,8-tetramethyl-5-formyl-6-hydroxychroman (C), trimer (D) and tocopherylethane (G) were identified, and spirodimer (E) was tentatively identified by TLC. Two of them, (B) and (C) have not been obtained in the oxidation of α-tocopherol model compound with p-quinone, alkaline ferricyanide and other compounds as oxidizing agent. A scheme of oxidation mechanism of α-tocopherol model compound was also proposed.     

衰老的分子机制与干预研究的最新进展

随着全球老龄化时代的到来,衰老和衰老相关疾病带来的健康问题日益突出。如何最大限度地维持老龄人口健康、干预衰老相关疾病并延缓衰老的发生对于医疗系统、科研机构乃至整个社会都是巨大的挑战。目前,对于衰老的分子机制研究已经有长足的进步,对于衰老进程的生物学和遗传学机制已有突破性的认识,对于衰老相关疾病的发病机制也有了深刻的理解。但这些研究成果还远远达不到能够延缓人类衰老并遏制衰老相关疾病的发生的要求。该文将从衰老的分子机制和干预手段这两个方面入手,综述衰老的理论研究和实际应用中的主要成果和最新进展。     

Studies on the Mechanism of the Sporicidal Action of Glutaraldehyde

S ummary . Low concentrations (0.025–0.125%) of glutaraldehyde inhibited or prevented colony formation by Escherichia coli, Bacillus subtilis and B. pumilis in agar, and inhibited germination of spores of the Bacillus spp. in L-alanine plus D-glucose. Higher concentrations (2%) of glutaraldehyde at pH 8.5 were sporicidal. Pre-treatment of spores with glutaraldehyde lessened release of dipicolinic acid when the spores were subsequently heated at 100°, but not at 121°. Spores treated with glutaraldehyde and then with 0.5 M thioglycollic acid in 6 M urea at 70° were less sensitive to lysis by hydrogen peroxide than spores which had not been exposed to glutaraldehyde. Glutaraldehyde was less effective in preventing peroxide induced lysis if added to spores which had been previously exposed to thioglycollic acid plus urea at 70°. The mechanism of the sporicidal activity of glutaraldehyde is discussed in relation to these findings.     

Immunological Studies on the Mechanism of Gold Hypersensitivity Reactions

Immunological studies were performed on 12 patients with rheumatoid arthritis who developed reactions to gold. IgE levels were found to be raised in 10 of 11 patients tested at the time of the gold reaction, returning to normal on stopping therapy. Two of 12 patients with gold reactions had positive in-vitro lymphocyte transformation responses to gold.It is suggested that dermatological side effects in particular are mediated by a type I hypersensitivity response.     

补肾解毒方抗脑老化机制的体外研究

摘要 目的：探讨补肾解毒方含药血清抗脑老化的体外分子机制。方法：采用过氧化氢诱导制备人脑胶质细胞衰老模型,使用补肾解毒方含药血清干预以期达到对人脑胶质细胞衰老模型的治疗效果,CCK-8法检测细胞活力,采用β-半乳糖苷酶染色法观察衰老阳性细胞比例,活性氧荧光探针法检测胞内活性氧水平,流式细胞术检测细胞凋亡比例,qPCR检测细胞中衰老相关基因CXCL1、FOXO1、P16、IL1A、IGFBP3、IL6的转录水平。结果：补肾解毒方含药血清可显著增强细胞活力（P＜0.05）,显著减少过氧化氢诱导的衰老阳性细胞比例（P＜0.05）,降低活性氧水平,显著减少凋亡细胞比例（P＜0.01）,下调IL1A、IL6、CXCL1、IGFBP3、FOXO1转录水平。结论：补肾解毒方含药血清可显著抑制过氧化氢诱导的人脑胶质细胞衰老,其可能与增强细胞活力、抗炎、抗凋亡、降低胞内活性氧水平等有关。     

浓香型白酒窖池细菌群落

利用PCR-SSCP技术研究了不同窖龄浓香型白酒窖池细菌群落的变化规律,结果发现:(1)所有窖泥样品均出现9-22条较清晰的条带,其中均表现出较高优势度的条带7条,但各样品优势条带的变化规律不同;(2)所有窖泥样品平均生物多样性指数都在1.93-2.82之间,随着窖龄的增加,相同位置样品的多样性指数总体上呈递增趋势;(3)同一窖池不同位置样品的PCR-SSCP图谱相似性指数较高,在0.63-1.00之间,不同窖龄窖池的SSCP图谱相似性指数较低,在0.34-0.76之间。