Enzyme-Cytochemistry of Human Chorion Laeve at Term: Enzyme Localization on the Chorionic Trophoblast

Erythrocyte ghosts containing varying amounts of alkaline phosphatase were used to study the localization mechanisms of three metal salt and one azo method for this enzyme. For the azo method, the minimal amount of alkaline phosphatase that can be visualized within the ghosts proved only to be limited by the optical properties of the azo compound. In contrast, for the metal salt methods, a certain threshold activity had to be present in the ghosts in order to obtain correct localization of the final reaction product. The localization properties of both azo and metal salt methods conformed to the theories of cytochemical enzyme localization presented to date. By determining the rate constant of the capture reaction and the diffusion constant of the primary product, the localization properties of the azo method could be predicted. Some remaining discrepancies between theory and practice are discussed.

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Gastric Ulcers Produced by Cisplatin

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099337 ◽

1981 ◽

Vol 39 ◽

pp. 582-583

Author(s):

S.K. Aggarwal ◽

J. San Antonio

Keyword(s):

Electron Microscopy ◽

Single Dose ◽

Side Effects ◽

Antitumor Agent ◽

Gastric Ulcers ◽

Enzyme Cytochemistry ◽

Intestinal Toxicity ◽

Ovarian Cancers ◽

Inner Surface

Cisplatin (cis-dichlorodiammineplatinum(II)) a potent antitumor agent is now available for the treatment of testicular and ovarian cancers. It is however, not free from its serious side effects including nephrotoxicity, gastro intestinal toxicity, myelosuppression, and ototoxicity. Here we now report that the drug produces peculiar bloating of the stomach in rats and induces acute ulceration.Wistar-derived rats weighing 200-250 g were administered cisplatin(9 mg/kg) ip as a single dose in 0.15 M NaCl. After 3 days the animals were sacrificed by decapitation. The stomachs were removed, the contents analyzed for pepsin and acidity. The inner surface was examined with a dissecting microscope after a moderate stretching for ulcers. Affected areas were fixed and processed for routine electron microscopy and enzyme cytochemistry.The drug treated animals kept on food and water consistently showed bloating and lesions (Fig. 1) with a frequency of 6-70 ulcers in the rumen section of the stomachs.

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Integrated morphometrical and electron energy loss image analysis in cytochemistry

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153981 ◽

1989 ◽

Vol 47 ◽

pp. 402-403

Author(s):

W.C. de Bruijn ◽

A.A.W. de Jong ◽

C.W.J. Sorber

Keyword(s):

Image Analysis ◽

Acid Phosphatase ◽

Chemical Analysis ◽

Active Form ◽

List Type ◽

Type Number ◽

Enzyme Cytochemistry ◽

Related Data ◽

Endogenous Peroxidase ◽

Electron Energy Loss

One aspect of enzyme cytochemistry is, whether all macrophage lysosomal hydrolytical enzymes are present in an active form, or are activated upon stimulation. Integrated morphometrical and chemical analysis has been chosen as a tool to illucidate that cytochemical problem. Mouse peritoneal resident macrophages have been used as a model for this complicated integration of morphometrical and element-related data. Only aldehyde-fixed cells were treated with three cytochemical reactions to detect different enzyme activities within one cell (for details see [1,2]). The enzyme-related precipitates anticipated to be differentiated, were:(1).lysosomal barium and sulphur from aryl sulphatase activity,(2).lysosomal cerium and phosphate from acid phosphatase activity and(3).platinum/di-amino-benzidine( D A B) complex from endogenous peroxidase activity.

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High time resolution enzyme cytochemistry of rod outer segment

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161953 ◽

1990 ◽

Vol 48 (3) ◽

pp. 878-879

Author(s):

Takuma Saito ◽

Toshihiro Takizawa

Keyword(s):

Enzyme Activities ◽

Outer Segment ◽

Rapid Change ◽

High Time Resolution ◽

Visual Cell ◽

Enzyme Cytochemistry ◽

Activation Effect ◽

Rod Outer Segment ◽

Enzymatic Cascades ◽

Rapid Drop

Cells and tissues live on a number of dynamic metabolic pathways, which are made up of sequential enzymatic cascades.Recent biochemical and physiological studies of vision research showed the importance of cGMP metabolism in the rod outer segment of visual cell, indicat ing that the photon activated rhodopsin exerts activation effect on the GTP binding protein, transducin, and this act ivated transducin further activates phosphodiesterase (PDEase) to result in a rapid drop in cGMP concentration in the cytoplasm of rod outer segment. This rapid drop of cGMP concentration exerts to close the ion channel on the plasma membrane and to stop of inward current brings hyperpolarization and evokes an action potential.These sequential change of enzyme activities, known as cGMP cascade, proceeds quite rapidly within msec order. Such a rapid change of enzyme activities, such as PDEase in rod outer segment, was not a matter of conventional histochemical invest igations.

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Studies of Vegetative Plant Tissue Compatibility/Incompatibility: The Role of Acid Phosphatase in Lethal Cell Senescence in an Incompatible Heterograft

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002336 ◽

1980 ◽

Vol 38 ◽

pp. 530-531

Author(s):

Randy Moore

Keyword(s):

Acid Phosphatase ◽

Thick Layer ◽

Cell Necrosis ◽

Enzyme Localization ◽

Vegetative Plant ◽

Cell Autolysis ◽

Graft Interface ◽

System 1 ◽

Thin Fibril

Previous work has indicated that the graft incompatihility between Sedrmi telephoides and Solanum pennellil involves cell necrosis that results In a thick layer of collapsed cells at the graft Interface. This necrotic layer insulates the stock from the scion, which results in abscission of the Sedum scion after 4-6 weeks due to desiccation and starvation. Thus, cell autolysis (which is restricted to Sedum) characterizes the Incompatibility response in this system (1). In order to elucidate the events that lead to cell autolysis, and thus better understand the cellular site and mode of action of cellular incompatibility, the appearance and fate of the hydrolytlc enzyme acid phosphatase (AP) was followed in both the compatible Sedum autograft and the incompatible Sedum/Solanum heterograft. Acid phosphatase was localized by a modified Gomori-type reaction; positive (i.e., including NaF inhibitor) and negative (lacking substrate) controls showed no enzymatic precipitate. Following an initial association with the endoplasmic reticulum (ER) and dictyosomes at 6-10 hours after grafting, AP activity in the compatible Sedum autograft is associated primarily with the plasmalemma (Fig. 1). By 18-24 hours after grafting, the AP activity is restricted to the tono-plast and vacuole (Fig. 2). This strict compartmentation and absence of enzyme from the cytosol is maintained throughout the development of the compatible graft. While AP activity in the incompatible Sedum/Solanum heterograft is Initially similar to the compatible Sedum autograft (i.e., initially found on the ER and dictyosomes), there is a marked difference in enzyme localization in the two graft partners as the incompatibility response develops. As in the compatible autograft, Solanum cells at the graft interface show an Increase in AP activity that Is restricted to the vacuole and tonoplast, with little or no enzyme activity in the cytosol (Fig. 3). In comparable Sedum cells, however, there is a dramatic Increase In AP activity in the cytosol (Fig. h); this cytosollc AP activity is associated with thin fibril-like structures (Fig. 5) measuring approximately 60 A in diameter. This high cytoplasmic AP activity In Sedum cells results in cell autolysis, death, and eventual cell collapse to form the characteristic necrotic layer separating the two graft partners.

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Contribution of Microscopy to a Better Knowledge of the Biology ofGiardia lamblia

Microscopy and Microanalysis ◽

10.1017/s1431927604040954 ◽

2004 ◽

Vol 10 (5) ◽

pp. 513-527 ◽

Cited By ~ 13

Author(s):

Wanderley de Souza ◽

Adriana Lanfredi-Rangel ◽

Loraine Campanati

Keyword(s):

Golgi Complex ◽

Laser Scanning ◽

Diarrheal Disease ◽

Freeze Fracture ◽

Laser Scanning Microscopy ◽

Confocal Laser ◽

Enzyme Cytochemistry ◽

Morphological Studies ◽

Transmission Electron ◽

Microscopic Techniques

Giardia lambliais a flagellated protozoan of great medical and biological importance. It is the causative agent of giardiasis, one of the most prevalent diarrheal disease both in developed and third-world countries. Morphological studies have shown thatG. lambliadoes not present structures such as peroxisomes, mitochondria, and a well-elaborated Golgi complex. In this review, special emphasis is given to the contribution made by various microscopic techniques to a better knowledge of the biology of the protozoan. The application of video microscopy, immunofluorescence confocal laser scanning microscopy, and several techniques associated with transmission electron microscopy (thin section, enzyme cytochemistry, freeze-fracture, deep-etching, fracture-flip) to the study of the cell surface, peripheral vesicles, endoplasmic reticulum–Golgi complex system, and of the encystation vesicles found in trophozoites and during the process of trophozoite-cyst transformation are discussed.

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