Isolation of a hexaprenylhydroquinone sulfate from the marine sponge Dysidea sp. as an H,K-ATPase inhibitor

A hexaprenylhydroquinone sulfate has been isolated as an H,K-ATPase inhibitor from a marine sponge Dysidea sp. It also inhibited phospholipase A2 as well as secretion of gastric acid in rats.     

5-Thio-d-glucose:o-diphenoloxidase inhibition as its mechanism of action

Summary 5-Thio-d-glucose completely inhibitedo-diphenoloxidase from animal as well as plant sources. It has been reported that thioglucose suppresses spermatogenesis in mice and also insect metamorphosis, probably through inhibition of glucose transport. Inhibition ofo-diphenoloxidase (which is active in spermatozoa and insect larvae) is suggested as an alternative mechanism of action of thioglucose.     

Isolation and characterization of a new hemagglutinin from the red alga Gracilaria bursa-pastoris

A new agglutinin has been isolated from the red alga Gracilaria bursa-pastoris by affinity chromatography on a yeast mannan-Cellulofine column. This agglutinin was isolated as a monomeric glycoprotein with a relatively low molecular weight. It had an isoelectric point of 4.7 and contained large amounts of Gly, Asx and Glx. It agglutinated trypsin-treated rabbit erythrocytes at the low concentration of 30 ng/ml. The activity was inhibited only by glycoproteins bearing N-glycans. This agglutinin also showed mitogenic activity for mouse splenic lymphocytes.     

硼氢化钠作为能量载体的新型能量转换技术(英文)

硼氢化钠作为能量载体的新型能量转换技术,它由直接硼氢化钠燃料电池、硼氯化钠水解制氢和硼氢化钠再生技术构成。通过总结了近年来在直接硼氢化钠燃料电池、硼氢化钠水解制氢和硼氢化钠再生技术上的进展,发现硼氢化钠作为能量载体的新型能量转换技术的雏形已日渐形成,本文总结和讨论了该项技术的优点和面临的挑战。     

Transthyretin: the servant of many masters

Transthyretin (TTR) (formerly, thyroxine binding prealbumin) is an evolutionarily conserved serum and cerebrospinal fluid protein that transports holo-retinol-binding protein and thyroxine. Its serum concentration has been widely used to assess clinical nutritional status. It is also well known that wild-type transthyretin and approximately 100 different mutants give rise to a variety of forms of systemic amyloid deposition. It has been suspected and recently established that TTR can suppress the Alzheimer’s disease phenotype in transgenic animal models of cerebral Aβ deposition. Thus, while TTR is a systemic amyloid precursor, in the brain it seems to have an anti-amyloidogenic effect. TTR is found in other organs as a result of local synthesis or transport, suggesting that it may have other, as yet undiscovered, functions. It is possible that its capacity to bind many classes of compounds allows it to serve as an endogenous detoxifier of molecules with potential pathologic effects.     

Isolation and characterization of a new hemagglutinin from the red algaGracilaria bursa-pastoris

Summary A new agglutinin has been isolated from the red algaGracilaria bursa-pastoris by affinity chromatography on a yeast mannan-Cellulofine column. This agglutinin was isolated as a monomeric glycoprotein with a relatively low molecular weight. It had an isoelectric point of 4.7 and contained large amounts of Gly, Asx and Glx. It agglutinated trypsin-treated rabbit erythrocytes at the low concentration of 30 ng/ml. The activity was inhibited only by glycoproteins bearing N-glycans. This agglutinin also showed mitogenic activity for mouse splenic lymphocytes.     

Effect of fasting on skeletal muscle triglyceride content

Summary The effect of prolonged food deprivation on the triglyceride level in different types of skeletal muscle was studied in the rat. It has been found that fasting gradually reduces the triglyceride content in each muscle type. It is concluded that i.m. triglycerides play an important role as energy fuel during fasting.     

Effect of fasting on skeletal muscle triglyceride content

The effect of prolonged food deprivation on the triglyceride level in different types of skeletal muscle was studied in the rat. It has been found that fasting gradually reduces the triglyceride content in each muscle type. It is concluded that i.m. triglycerides play an important role as energy fuel during fasting.     

Occurrence of polyploidy and multinuclearity in the differentiating liver of chick embryo

Summary Increase in nuclear size in liver has been used as an index of polyploidy. It has long been considered that the occurrence of polyploidy and multinuclearity are characteristics of mammalian liver. The present study shows the occurrence of these phenomena in the liver of birds, so these features are not confined to mammals. 3 classes of nuclear size groups have been identified. The simultaneous occurrence of polyploidy and binuclearity indicates some sort of interrelationship between them.     

Die polarographische Untersuchung von Chalkonen und Flavanonen

Summary It has been found by polarographic analysis in neutral or acid solution that chalcones show two reduction potentials, while flavanones show only one.It was possible to determine 2'-hydroxy-chalcone beside flavanone with a polarograph.The formation rate of a chalcone from an aldehyde and a ketone could be followed polarographically.     

Making more synapses: a way to store information?

Although information may be stored in the brain as changes in the strength of existing synapses, formation of new synapses has long been thought of as an additional substrate for memory storage. The identification of subcellular structural changes following learning in mammals poses a serious ‘needle-in-the-haystack’ problem. In most attempts to demonstrate structural plasticity during learning, animals have been exposed for prolonged periods to complex environments, where they are confronted with a variety of sensory, motor and spatial challenges throughout the exposure period. These environments are thought to promote several forms of learning. Repeated exposure to such environments has been shown to increase the density of spines and dendritic complexity in relevant brain structures. The number of neurons has also been reported to increase in some areas. It is not clear, however, whether the new synapses emerging from these forms of plasticity mediate specific information storage, or whether they reflect a more general sophistication of the excited parts of the network.     

核受体LXRa靶基因研究进展

核受体的研究近几年已有飞速的发展。LXRa(Liver X Receptor a)是一种与脂类代谢有关的核受体。研究发现LXRa的靶基因具有调节脂类的吸收、运输、转化和生物合成的功能,此外,LXRa在糖类的代谢等方面也有重要的调控作用。研究结果表明LXRa与动脉粥样硬化的发生有非常密切的关系。目前利用LXRa为靶标进行抗动脉粥样硬化药物筛选已经成为一个重要的研究方法。     

Isolation of the yellow fever virus from an egg-cluster and the larvae of the tick Amblyomma variegatum]

The yellow fever virus is isolated in natura from eggs of a Tick Amblyomma variegatum. It is then isolated from larvae issued from the same egg-cluster and also from blood of a monkey bitten by larvae of the same origin. It is reported that the same virus has been previously obtained from adults of the same species of Tick. An acarine appears for the first time as a sylvatic vector and reservoir (at least temporary) of yellow fever.     

The locus ceruleus: a possible neural focus for genetic differences in emotionality

The Maudsley Reactive and Non-Reactive strains have been developed as a model for the study of individual variations in stress-reactivity, and many differences in biobehavioral systems have been found between them. This review discusses limitations of the 'emotionality' construct in accounting for differences between the Maudsley strains and offers an alternative, theoretical approach. Amaral and Sinnamon have proposed that the locus ceruleus (LC) plays a stress-attenuating role in mediating behavioral, physiological and neuroendocrine response to prepotent, emergency-provoking stimuli and, building upon this formulation, it is proposed that the LC has been an important focus for gene action in the Maudsley model. It is suggested that the LC of the Non-Reactive strain is more strongly activated by stressful stimuli than the LC of Reactive rats, and is the basis of many of the behavioral and physiological differences between them. Behavioral and biochemical evidence consistent with this proposition is reviewed. Identification of the LC as a target for gene-action in the Maudsley model has an important advantage. It substitutes variations at a specific anatomic location in the brain for a loosely defined construct like emotionality, and the hypothesis is amenable to empirical tests by a variety of experimental approaches.     

The dental amalgam issue. A review

Summary Using an interdisciplinary approach, the current position in the dental amalgam controversy and the potential impact of amalgam mercury on human health are reviewed. Aspects of materials science, corrosion, mercury exposure, toxicology, neurology and immunology are included.New data on mercury exposure from corroded amalgam fillings in vivo are presented. The exposure can reach levels considerably over known threshold limit values. Also, measurements of mercury absorption from intraoral air are presented. The vital importance of avoiding a galvanic amalgam-gold coupling is emphasized. The symptomatology of a disabled patient, who recovered after amalgam removal, has been included.It is concluded that discussion of the dental amalgam issue has suffered from the lack of an interdisciplinary approach. It would be wise to learn from the lesson of acrodynia, and consider amalgam mercury among other possible factors in neurological and immunological diseases of unclear etiology.     

The dental amalgam issue. A review

Using an interdisciplinary approach, the current position in the dental amalgam controversy and the potential impact of amalgam mercury on human health are reviewed. Aspects of materials science, corrosion, mercury exposure, toxicology, neurology and immunology are included. New data on mercury exposure from corroded amalgam fillings in vivo are presented. The exposure can reach levels considerably over known threshold limit values. Also, measurements of mercury absorption from intraoral air are presented. The vital importance of avoiding a galvanic amalgam-gold coupling is emphasized. The symptomatology of a disabled patient, who recovered after amalgam removal, has been included. It is concluded that discussion of the dental amalgam issue has suffered from the lack of an interdisciplinary approach. It would be wise to learn from the lesson of acrodynia, and consider amalgam mercury among other possible factors in neurological and immunological diseases of unclear etiology.     

Tubular and glomerular nephropathy induced in rabbits by injection of a heterologous antitubular basement membrane serum]

A nephropathy affecting both tubules and glomeruli has been induced in Rabbits by the injection of an heterologous immune serum directed against Rabbit tubular basement membrane. It differs from experimental antiglomerular basement membrane nephropathy by the fixation of antibodies and C3 on tubular basement membrane and by the occurrence of glucosuria.     

Hsp70 in parasites: as an inducible protective protein and as an antigen

The heat shock (HS) response is a general homeostatic mechanism that protects cells and the entire organism from the deleterious effects of environmental stresses. It has been demonstrated that heat shock proteins (HSP) play major roles in many cellular processes, and have a unique role in several areas of cell biology, from chronic degenerative diseases to immunology, from cancer research to interaction between host and parasites. This review deals with thehsp70 gene family and with its protein product, hsp70, as an antigen when pathogens infect humans. Members of HSP have been shown to be major antigens of many pathogenic organisms when they experience a major temperature shift upwards at the onset of infection and become targets for host B and T cells.