Pristine C60 Fullerene Nanoparticles Ameliorate Hyperglycemia-Induced Disturbances via Modulation of Apoptosis and Autophagy Flux

Neurochemical Research - Diabetes mellitus is a prevalent metabolic disorder associated with multiple complications including neuropathy, memory loss and cognitive decline. Despite a long history...     

Halogenated Kojic Acid Derivatives,Related Compounds,and their Physiological Eflects on Plant Growth

Kojic acid has a slight stimulatory effect on plant growth as measured by the use of duckweed grown under aseptic conditions on a synthetic liquid medium. It is thought that this stimulation is due to the formation of chelatcs. This presentation is primarily concerned with the effect of various derivatives of kojic acid, particularly halogenated derivatives, on plant growth as measured by this same system. Halogenation of the 2-position results in toxic compounds. Substitution in the 6-position results in compounds with beneficial growth effects. Blockage of the 5-position causes a loss of stimulatory ability, interpreted as a loss of chelating power.     

Studies on the Degradation Mechanisms of Proteins and their Derivatives in the Foods

The volatile sulfur components produced by boiling soybean meal hydrolyzates (AMINOSAN-EKI) have been identified as dimethyl sulfide and hydrogen sulfide. No mercaptan or disulfides were detected.

The main precursor of dimethyl sulfide is supposed to be methionine methylsulfonium compound derived from methionine and pectin substances (–COOCH₃) during the hydrolysis of soybean meal by hydrochloric acid.     

Studies on the Degradation Mechanisms of Proteins and their Derivatives in the Foods

Cysteine-aldehyde compounds were prepared by the reactions of l-cysteine with formaldehyde, acetaldehyde, n-butyraldehyde, benzaldehyde and furfural in 50% ethanol solutions. Hydrogen sulfide and ammonia liberated from cysteine-aldehyde compounds in heated aqueous solutions (oil bath : 120°C) were determined. Although thiazolidine derivatives were stable generally in boiling aqueous solution, l-cysteine-furfural compound was unstable and a large amount of hydrogen sulfide compared with other compounds was released.     

Studies on Chlorosis-Inducing Activities and Plant Growth Inhibition of Benzophenone Derivatives

Some benzophenones substituted with methyl, methoxy, hydroxy or halogen groups inhibited growth and induced chlorosis in various plants. The structure activity relationships about the chlorosis-inducing activity and the growth inhibitory activity of the 3-methyl-benzophenones were well expressed by use of hydrophobic contant π, and Hammett’s σ. The highest selectivity for phytotoxic activities against barnyardgrass and the rice plant was with 3,3′-dimethyl-4-methoxybenzophenone (Methoxyphenone).     

不同剂量柚皮素对FADU细胞生长的调节及机制研究

目的:探究不同剂量柚皮素(naringenin)对人下咽癌FADU细胞的作用及其相关机制。方法:以不同剂量(0、100、200、400、800μg/m L)柚皮素对FADU细胞进行处理,倒置显微镜观察细胞形态学变化;cck-8法检测药物作用后不同时间(24、48、72 h)FADU细胞增殖的变化;流式细胞仪检测柚皮素作用48 h细胞凋亡的变化;采用Transwell趋化小室体外侵袭实验测定48 h后细胞的侵袭能力的变化;蛋白免疫印迹法检测48 h后细胞内PI3K/AKT信号通路凋亡相关蛋白表达的影响。结果:cck-8法检测发现柚皮素抑制FADU细胞增殖作用明显,呈浓度和时间依赖性;流式细胞结果发现200,400,800μg/m L柚皮素作用48 h后,FADU细胞的凋亡率显著增高,差异有统计学意义(P0.05)。Transwell体外侵袭实验发现,随着柚皮素浓度增加,FADU细胞穿透聚碳酸酯滤膜的能力逐渐减弱,柚皮素有效的抑制FADU细胞在体外的侵袭能力,呈浓度依赖性。同时,蛋白免疫印迹法凋亡相关蛋白检测结果表明,FADU细胞内BCL2、P-AKT和P-PI3K蛋白表达均受到明显抑制。结论:柚皮素能有效抑制人下咽癌FADU细胞的增殖、体外侵袭能力,诱导细胞凋亡;其机制与下调PI3K/AKT信号通路凋亡相关蛋白表达有关。     

A Comparison of the Effect of 6-Benzylaminopurine Derivatives on some Aspects of Plant Growth

Soybean callus treated with 6-benzylaminopurine and its riboside elicit better growth than 6-benzyladenosine 5′-monophosphate. This can probably be attributed to differences in the rate at which the different compounds are taken up and/or metabolized. In the case of lettuce seed germination the ribotide is unable to substitute for red light in the dark; this supports previous suggestions that in certain situations it is physiologically less active than the free base or riboside.     

Jasmonates,New Regulators of Plant Growth and Development: Many Facts and Few Hypotheses on their Actions

Jasmonates, ubiquitous cyclopentanone compounds, are reviewed as new regulators for plant growth and development. They may complement the group of well-established “classic” phytohormones. Jasmonates influence a multiplicity of plant physiological processes by inhibition, promotion or induction. In many aspects they are similar to abscisic acid, especially in responses to stress. The review contains information on the chemical structures and metabolism of jasmonates, contributes to their biological role and describes possible mode(s) of action at the level of molecular biology and gene expression. In particular, emphasis is placed on the gene expression and accumulation of jasmonate-induced abundant polypeptides as a stress response of the plant cells. A hypothesis is attempted in which endogenous jasmonates represent an integral part of the signal transduction chain between stress signal(s) and stress response(s).     

The Effect of the Ethylene Action Inhibitor 1-Cyclopropenylmethyl Butyl Ether on Early Plant Growth

Increased levels of ethylene in plants are responsible for many deleterious effects such as early senescence, fruit deterioration and inhibition of root elongation. Several cyclopropene derivatives have previously been studied as inhibitors of ethylene action in plants. This study focuses on one such compound, 1-cyclopropenylmethyl butyl ether and its effect on the growth of roots and shoots of canola plants as well as rooting of mung bean seedlings 1-cyclopropenylmethyl butyl ether increased root length in canola plants, but had no significant effect on shoot length. In rooting studies, mung bean seedlings treated with 1-cyclopropenylmethyl butyl ether prior to root excision had fewer numbers of roots than control plants that were not treated with the ethylene action inhibitor. The same rooting study, when repeated in the presence of 1-aminocyclopropane-1-carboxylic acid (ACC), demonstrated an overall increase in the number of roots of inibitor-treated and non-treated plants, however, the inhibitor was still effective in decreasing the number of roots, compared to its non-treated conterpart. Online publication: 7 April 2005     

The Action of Fusicoccin Alone and with Some Plant Growth Substances on Tobacco Tissue Cultures

The interaction of fusicoccin, a terpenoid glucoside produced by Fusicoccum amygdali Del., and some plant growth regulating substances, i.e., indole-3-acetic acid, kinetin, 2,4-dichlorophenoxy-acetic acid and abscisic acid, was investigated on pith and sub-cultured callus cultures of Nicotiana tabacum L. Addition of fusicoccin alone to the basal medium, either in the light or in the dark, caused a fairly good development of tobacco callus. When fusicoccin and kinetin were simultaneously added to the culture medium, the callus growth increased. However, fusicoccin in combination with indole-3-acetic acid caused limited callus development: the tissue appeared brown and reduced in volume. Addition of fusicoccin with 2,4-dichlorophenoxyacetic acid stimulated growth of callus and chlorophyll was formed under light. Finally, abscisic acid did not interfere with the effect of fusicoccin on the callus growth.     

Action Mechanisms of the Secondary Metabolite Euplotin C: Signaling and Functional Role in Euplotes

ABSTRACT. Among secondary metabolites, the acetylated hemiacetal sesquiterpene euplotin C has been isolated from the marine, ciliated protist Euplotes crassus, and provides an effective mechanism for reducing populations of potential competitors through its cytotoxic properties. However, intracellular signaling mechanisms and their functional correlates mediating the ecological role of euplotin C are largely unknown. We report here that, in E. vannus (an Euplotes morphospecies that does not produce euplotin C and shares with E. crasssus the same interstitial habitat), euplotin C rapidly increases the intracellular concentration of both Ca²⁺ and Na⁺, suggesting a generalized effect of this metabolite on cation transport systems. In addition, euplotin C does not induce oxidative stress, but modulates the electrical properties of E. vannus through an increase of the amplitude of graded action potentials. These events parallel the disassembling of the ciliary structures, the inhibition of cell motility, the occurrence of aberrant cytoplasmic vacuoles, and the rapid inhibition of phagocytic activity. Euplotin C also increases lysosomal pH and decreases lysosomal membrane stability of E. vannus. These results suggest that euplotin C exerts a marked disruption of those homeostatic mechanisms whose efficiency represents the essential prerequisite to face the challenges of the interstitial environment.     

Mechanisms and Physiologic Significance of Microwave Action on the Auditory System

Studies conducted by the authors and their coworkers on the mechanisms and physiologic significance of radiofrequency hearing effects are reviewed. Results of these studies demonstrate that 1) thermoelastic expansion of fluids and structures within the inner ear is the main mechanism by which auditory stimuli are produced by microwave pulses; 2) the frequency spectra of these stimuli are indistinguishable from the spectra of rectangular pulses with the same durations as the microwave pulses; 3) exposure to continuous-wave (CW) microwave radiation evokes an increase in the metsbolic activities of nuclei in the ascending auditory pathway and also decreases the latency and increases the magnitude of brainstem-evoked responses produced by acoustic clicks; and 4) the mechanism of the effects of CW microwave radiation on the auditory system is intracochlear heating. The significance of these findings is discussed in terras of potential applications of microwave stimuli in basic research on the auditory system and in terms of interpreting the results of past studies that demonstrate behavioral sensitivity to CW microwave fields.     

白藜芦醇对肿瘤细胞HL-60代谢热化学研究

目的：用微量热法研究了白藜芦醇对白血病细胞HL-60代谢作用的热化学特征。方法：等温量热仪测定HL-60细胞在白藜芦醇作用下生长代谢的热功率输出曲线。结果：白藜芦醇在20μg/mL-80μg/mL范围内,热曲线一直处于缓慢下降状态,对该肿瘤细胞有明显抑制作用,当计量达到100μg／mL-120μg／mL时,热功率曲线值呈缓慢增加趋势,抑制效果变弱。结论：白藜芦醇对细胞HL-60代谢有明显的抑制作用,为白藜芦醇在防治肿瘤中的应用提供了可靠的信息。     

Enhanced Efficiency of In Vitro Rootstock Micro-propagation Using Silica-Based Nanoparticles and Plant Growth Regulators in Myrobalan 29C (Prunus cerasifera L.)

Different experiments were conducted to establish and optimize an efficient in vitro micropropagation protocol for Myrobalan 29C rootstocks. Disinfection of initial explants with AgNPs (2.5%) reduced the needed amount of NaClO (5.0%) by half. The highest rates of induced active buds were obtained in the DKW (90.63%), MS (86.67%), modified MS (82.22%), and WPM (78.15%) culture media supplemented with BAP (2.22 μmol L^?1)?+?GA₃ (2.88 μmol L^?1)?+?IBA (0.05 μmol L^?1)?+?Fe-EDDHA (228.72 μmol L^?1). The highest quality of the proliferated shoots (5.0) was also achieved using DKW medium. Inclusion of GA₃ (5.76 μmol L^?1), Fe-EDDHA (114.36–228.72 μmol L^?1), or BAP (2.22 μmol L^?1) were also able to enhance the rate of shoot multiplication. Compared to the agar-solidified culture system, the established shoots proliferated more efficiently when immersed by bioreactor in the liquid DKW culture medium on a regular basis. Exogenous application of silica-based nanoparticles (NPs) including the chemically synthesized silica NPs (TSiO₂ NPs, 1.0 ppm), rice husk derived biogenic silica NPs (RSiO₂ NPs, 10.0 ppm), or amine modified silica NPs (ASiO₂ NPs, 10.0 ppm) to the multiplication medium increased the number of regenerated lateral shoots by 520%, 360%, and 349%, respectively. Proliferated shoots with well-developed root system were obtained from the rooting medium supplemented with 19.68 μmol L^?1 IBA. Our results indicated that the rootstocks of Myrobalan 29C could be efficiently propagated under in vitro condition providing proper culture medium and optimal concentrations of additives and plant growth regulators were adopted.

     

Studies on the Degradation Mechanisms of Proteins and Their Derivatives in the Foods

Cysteine mercaptals and mercaptoles were prepared by the reactions of l-cystine with formaldehyde, acetaldehyde, n-butyraldehyde, benzaldehyde, furfural, pyruvic acid and levulinic acid in 6 n hydrochloric or sulfuric acid. Hydrogen sulfide released from cysteine mercaptals and mercaptoles in heated aqueous solutions (oil bath: 120°C) was determined. Although a small amount of hydrogen sulfide was liberated from l-cystine on one hour heating, its amount increased suddenly after three hours. Among these compounds l-cystine mercaptal of furfural was most unstable and a large amount of hydrogen sulfide was produced.