A comparative immunohistochemical study of Kuru and senile plaques with a special reference to glial reactions at various stages of amyloid plaque formation.

The authors examined 10 patients with Gerstmann-Sträussler syndrome or Creutzfeldt-Jakob disease and 10 with Alzheimer''s disease (AD). Immunohistochemistry using anti-prion protein (PrP) and anti-beta/A4 protein (beta/A4) coupled with formic acid pretreatment could detect Congophilic and non-Congophilic deposits. Prion protein deposits were classified into five types and compared with types of beta/A4 deposits. Kuru plaques with multicentric cores and fine granular deposits were a characteristic feature of PrP deposits. Some types of PrP or beta/A4 deposits depend on the anatomic sites. To clarify the relationship of microglia and astrocytes to PrP or beta/A4 deposits, double-immunostaining method was performed. In both kuru and senile plaques, microglia were closely linked to the Congophilic plaques. Astrocytes, however, extended their processes toward the plaques even in the non-Congophilic plaques. These observations strongly suggest that similar glial association with plaque formation may be involved in both kuru and senile plaques, although the amyloid core proteins differ.     

The laboratory of tomorrow. Particular reference to hematology

A serious prediction can only be an extrapolation of recent developments. To be exact, the development has to continue in the same direction, which is only a probability. Probable development of hematological technology: Progress in methods. Development of new labelling methods: radio-elements, antibodies. Monoclonal antibodies. Progress in equipment: Cell counters and their adaptation to routine hemograms is a certainty. From analyzers: a promise that will perhaps become reality. Coagulometers: progress still to be made. Hemagglutination detectors and their application to grouping: good achievements, but the market is too limited. Computerization and automation: What form will the computerizing take? What will the computer do? Who will the computer control? What should the automatic analyzers be? Two current levels. Relationships between the automatic analysers and the computer. Advantages: rapidity, fidelity and above all, reliability. Memory: large capacity and easy access. Disadvantages: conservatism and technical dependency. How can they be avoided? Development of the environment: Laboratory input: outside supplies, electricity, reagents, consumables. Samples and their identification. Output: distribution of results and communication problems. Centralization or decentralization? Conclusions: What will tomorrow's laboratory be? 3 hypotheses: optimistic, pessimistic, and balanced.     

A comparative cytochemical study of the yolk platelets in the growing oocytes of Triturus cristatus and Rana esculenta.

Recent cytochemical techniques for the detection of proteins, neutral and acid mucopolysaccharides, lipids and phospholipids in the yolk platelets of the growing oocytes of Rana esculenta and Triturus vulgaris are employed. Cytochemical analysis showed that the yolk in the form of granules or platelets, in the constituting itself the most prominent cytoplasmic inclusion of amphibian eggs, contains a protein moiety consisting of individual typical amino acids lacking tryptophan in Triturus, a carbohydrate fraction consisting of neutral mucopolysaccharides distributed in the superficial layer of each platelet, and phospholipids, phosphoproteins and lipoproteins which are present only in the main body of the same platelets. The different amino acid composition indicated a protein heterogeneity which could be connected with the tissue incompatibility of the transplantations when these last were effected between the orders Urodela and Anura. The different protein composition of the yolk also can be reflected at the species-specific level. The cytochemical data are further reviewed with the mode of utilization of the yolk platelets.     

An ultrastructural, cytochemical, and autoradiographic study of the mucous membrane of the human cervical canal with reference to subcolumnar basal cells.

This study presents a detailed ultrastructural examination of the human endocervix with evidence for the differentiation of subcolumnar basal cells into mucus-secreting cells and ciliated columnar cells. Cytochemical studies in which peroxidatic activity was used indicate that there are two cell types in the endocervical mucosa which can be distinguished by different localization of reaction product. It may be that estrogen sensitivity accounts for such differences. Autoradiographic investigations demonstrated that glandular cells and subcolumnar basal cells synthesize DNA in premenopausal and postmenopausal women. In addition, subcolumnar basal cells actively synthesized RNA, reflecting their ability for further growth and development.     

Evaluation of four automated hematology analyzers. A comparative study of differential counts (imprecision and inaccuracy).

The authors evaluated the performance of four modern, commercially available hematology analyzers for imprecision and inaccuracy in determining the leukocyte differential count. The evaluation was performed according to International Committee for Standardization in Haematology protocols and the National Committee for Clinical Laboratory Standards H20-T standard, using the same group of patients simultaneously. Imprecision was very low among all the analyzers for neutrophils and lymphocytes (coefficient of variation maximum = 4.12%), whereas for the other leukocyte populations it tended to increase as their presence percentage decreased. The imprecision of the analyzers was still lower than that of the microscopic method. The correlation with the manual 800 cell count (inaccuracy) was good for neutrophils, lymphocytes, and eosinophils (r = 0.974 to 0.888), less so for monocytes (r = 0.757 to 0.490), whereas it was poor for basophils (r = 0.532 to 0.078).     

Lymphocytic ("microscopic") colitis: a comparative histopathologic study with particular reference to collagenous colitis

Lymphocytic colitis, previously termed "microscopic colitis", is a clinicopathologic syndrome of watery diarrhea, grossly normal colonoscopy, and mucosal inflammatory changes. Since lymphocytic colitis is a new, incompletely characterized entity, a histopathologic study was performed to compare lymphocytic colitis (n = 16), collagenous colitis (n = 17), idiopathic inflammatory bowel disease (n = 16), acute colitis (n = 16), and histologically normal colon (n = 12). The study was a blinded semiquantitative analysis of histologic features in the surface epithelium, lamina propria, and crypts. The most distinctive feature of lymphocytic colitis was increased intraepithelial lymphocytes, particularly in the surface epithelium (P = .0001 v idiopathic inflammatory bowel disease, acute colitis, and normal colon). Other prominent features of lymphocytic colitis included surface epithelial damage (P less than .005 v idiopathic inflammatory bowel disease and normal colon), increased lamina propria chronic inflammation (P less than .01 v normal), and minimal crypt distortion or active cryptitis. There were striking similarities between lymphocytic colitis and collagenous colitis, but subepithelial collagen thickening was seen only in collagenous colitis. Idiopathic inflammatory bowel disease showed prominent crypt distortion and greater active inflammation, in addition to minimal intraepithelial lymphocytes. Acute colitis occasionally demonstrated prominent surface epithelial damage, but was otherwise dissimilar from lymphocytic colitis. We reached the following conclusions: (1) the entity "microscopic colitis" shows characteristic histopathology including prominent lymphocytic infiltration of epithelium, and thus, a more appropriate designation is lymphocytic colitis; (2) although lymphocytic colitis closely resembles collagenous colitis, each entity is distinct on biopsy; and (3) lymphocytic colitis is readily distinguishable from idiopathic inflammatory bowel disease, acute forms of colitis, and normal colorectum.     

A contribution to the study of the afferents to the pigeon optic tectum

Summary The origins of several afferent pathways to the pigeon's tectum were studied using the horseradish peroxidase tracing technique. The results confirm the presence of several previously described afferents, and add further data on intertectal and hyperstriatofugal projections. Two new sources of afferents to the tectum, located in the hypothalamus and the septum, were identified. The latter is described in greater detail.     

Ultrastructural and cytochemical studies of the subcommissural organ in the domestic chicken with special reference to the apical secretion.

Ultrastructural and cytochemical studies were undertaken with special reference to the apical secretion in the ependymal cells of the subcommissural organ in the domestic chicken. Glucose-6-phosphatase (G6Pase) and acid phosphatase (AcPae) were used as cytochemical markers for the endoplasmic reticulum (ER) and lysosomes, respectively. Periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) cytochemistry was employed to detect glycoconjugates. Most dense bodies were negative with AcPase staining. Dilated cisternal of ER were reacted with G6Pase cytochemistry. Golgi saccules and several kinds of spherical bodies were stained with PA-TCH-SP cytochemistry. Our results suggest that: 1) most dense bodies in the apical cytoplasm belong to the secretory granules discharged into the ventricular cavity, 2) dilated cisternae of the ER serve as the storage site of the substance which eventually becomes the secretory product, however, contents of the ER are not directly released into the ventricular cavity. Findings of this studies lead us to speculate that there are two intracellular transportation via different compartments: one is a transport via small vesicles from the perinuclear ER to the Golgi apparatus and the other is a transport bypassing the Golgi apparatus via cisternae of ER from the perinuclear ER to the supra-Golgi region. The substances in these two structures seem to be intermingled with each other and matured into secretory granules. This granules may be discharged into the ventricular cavity by exocytosis.