Personnel available in Histochemistry

The routine production of large sections and of a few sections from a large number of blacks of tissue embedded in nitrocellulose often presents difficulties, large blocks often loosen if cemented to an intermediate carrier in the routine manner.     

Histochemistry of Plasmalogen

Unfixed frozen sections of kidney, heart and brain from Wistar rats were used for the following tests: 1. relative reactivity of plasmalogen in different tissues to fuchsin-sulfurous acid (FSA); 2. effect of various mercury compounds in producing the plasmal reaction, and use of dithizone to verify the attachment of mercury to tissue plasmalogen; 3. effect of pH as shown by graded concentrations of HCl and by phosphate and acetate buffers; 4. effect of various cations; 5. solubility of plasmalogen in methanol, ethanol, isopropanol, n-butanol, t-butanol, n-pentanol and ethylene glycol; 6. effect of blocking reactions: acetal formation, bromination and iodination. The results showed that the amount of plasmalogen in brain is very much greater than that in heart muscle or in kidney and that the brain plasmalogen appears to be more reactive. All the highly ionized mercury compounds, HgCl₂, Hg(NO₃)₂, Hg(CH₃COO)₂, and HgNO₃ gave identical, immediate reactions. The moderately ionized K₂HgI₄ gave a less rapid reaction. Hg compounds which are unable to deliver any appreciable amount of mercuric ion into solution (nonionized or insoluble) did not react. Dithizone, which forms a deep red color in combination with Hg-containing compounds, gave a positive reaction at the same sites that gave the plasmal reaction. This indicates that the Hg combines with tissue plasmalogen. The hydrolysis of plasmalogen as a function of pH and time showed that 6 N HCl gave as rapid a reaction as HgCl₂. As the pH was increased the rate of plasmal formation decreased. At pH 4.0 no plasmal was evident in 2 hr. AuCl₃ and PdCl₂ gave reactions identical with that of HgCl₂. No other cation tested gave a plasmal reaction. Plasmalogen was rapidly dissolved by the short chain monohydric alcohols but not by ethylene glycol. Plasmalogen did not dissolve appreciably in 60% or lower grades of ethanol. Bromination or iodination abolished the plasmal reaction, but iodination required a longer time to do so. A 1.2 N HCl solution in ethylene glycol inhibited the HgCl₂-FSA reaction by the formation of an acetal which is relatively insensitive to HgCl₂, but it did not inhibit the FSA reaction when hydrolysis was by 6 N HCl instead of HgCl₂. The vinyl ether structure proposed by Rapport and associates (1957) for plasmalogen is supported by the specific reaction with HgCl₂, the hydrolysis with acid, the addition of iodine, of bromine, and the formation of an acetal.     

基因治疗中外源基因的导入

基因治疗是将遗传物质导入靶细胞以达到治疗疾病的目的,目前基因治疗研究中的主要障碍是如何格外源基因导入靶细胞。本介绍基因治疗的原理和外源基因导入靶细胞时的常用方法,包括显微注射法、电穿孔法、基因枪粒子轰击法等。对基因治疗的现状、存在的问题及未来发展前景作了简要探讨。     

Histochemistry for nucleic acid research: 60 years in the European Journal of Histochemistry

Since the discovery of DNA structure in 1953, the deoxyribonucleic acid has always been playing a central role in biological research. As physical and ordered nucleotides sequence, it stands at the base of genes existence. Furthermore, beside this 2-dimensional sequence, DNA is characterized by a 3D structural and functional organization, which is of interest for the scientific community due to multiple levels of expression regulation, of interaction with other biomolecules, and much more. Analogously, the nucleic acid counterpart of DNA, RNA, represents a central issue in research, because of its fundamental role in gene expression and regulation, and for the DNA-RNA interplay. Because of their importance, DNA and RNA have always been mentioned and studied in several publications, and the European Journal of Histochemistry is no exception. Here, we review and discuss the papers published in the last 60 years of this Journal, focusing on its contribution in deepening the knowledge about this topic and analysing papers that reflect the interest this Journal always granted to the world of DNA and RNA.Key words: Cell nucleus, nucleic acids, chromatin, RNA processing, electron microscopy, immunohistochemistry, flow cytometry     

基因合成技术研究进展

基因合成是生物学中一项最基本的、最常用的技术.对DNA调控元件、基因、途径乃至整个基因组的合成是验证生物学假设和利用生物学为人类服务的有力工具.合成生物学的快速发展对基因合成能力提出了日益迫切的需求.近年来,基于微芯片基因合成技术取得了很多令人振奋的新进展,正在向着高通量、高保真、自动化的方向发展.文中综述了DNA化学合成和基因组装及相关技术的最新研究进展和发展趋势,这些新技术正在推动着合成生物学向着更高的水平发展.     

Histochemistry of sialo-mucins in connective tissues

Summary The present investigation was undertaken in an effort to differentiate histochemically between sialo-mucins and acid mucopolysaccharides in connective tissues.On the basis of previous studies regarding the histochemical identification of sialic acid in sections of animal salivary glands the author applied different technical procedures on cartilage and tooth germs of newborn rats.The results obtained indicated that in the tissues examined sialic acid is a normal component of the polysaccharide fraction of the connective tissue ground substance.On leave of absence at the University of Rome, Medical School, Viale Regina Elena 287-A, Rome, Italy.     

Histochemistry of implantation in the rabbit

Summary The distribution of glycogen, acid and neutral mucopolysaccharides, hydrolases alkaline phosphatases, and carbohydrate dehydrogenases is described in the rabbit blastocyst and its surroundings over the implantation period from 5 to 9 days.Glycogen is found mainly in the embryonic tissues, where peaks of concentration coincide with differentiation, some is also seen in the uterine epithelium and secretion, and large quantities accumulate in the developing decidua.Neutral mucopolysaccharide is found in the yolk-sac and embryonic endoderm, and as secretion droplets in the uterine epithelium and secretion.Acid mucopolysaccharide occurs in the embryonic coverings and uterine secretion.RNA is associated in the embryo with developing tissues, and accumulates in the developing decidual cells.Hydrolases (acid phosphatase, and B esterase) increase their activity in the trophoblast knobs, in developing syncytiotrophoblast, and in the embryonic endoderm. Degeneration of the uterine epithelium is associated with maximal hydrolase activity.Trophoblastic alkaline phosphatase activity (non-specific and specific) decreases from 5 to 7 days of gestation, then increases markedly in the developing syncytiotrophoblast. AMPase appears in the embryonic mesoderm. In the uterine epithelium intense brush border staining is seen, and TPPase and UDPase become visible for a short period in the Golgi region. Phosphatases increase their activity in the decidua to 8 days and then decrease.Carbohydrate dehydrogenases (except -glycero-phosphate and -hydroxy-butyrate dehydrogenases) increase their activity in embryonic tissues, particularly in the developing syncytiotrophoblast and endoderm. Symplasma formation in the uterine epithelium is also associated with increase in enzyme activity, and a similar increase, up to 8 days of gestation, is seen in the decidua with isocitrate, malate, glucose-6-phosphate, lactate, succinate, and furfuryl alcohol dehydrogenases.Some correlation is found between the histochemical findings and the phenomena of epithelial removal, uterine secretion, decidual formation and function, giant cell function, morphogenesis, and histiotrophic nutrition, and the results are compared with previous findings for the rat in which implantation is morphologically, and probably physiologically a very different process.     

Histochemistry: Live and in Color

Histochemistry—chemistry in the context of biological tissue—is an invaluable set of techniques used to visualize biological structures. This field lies at the interface of organic chemistry, biochemistry, and biology. Integration of these disciplines over the past century has permitted the imaging of cells and tissues using microscopy. Today, by exploiting the unique chemical environments within cells, heterologous expression techniques, and enzymatic activity, histochemical methods can be used to visualize structures in living matter. This review focuses on the labeling techniques and organic fluorophores used in live cells.