Sampling problems in an heterogeneous organ: Quantitation of relative and total volume of pancreatic islets by light microscopy

1983 ◽  
Vol 132 (1) ◽  
pp. 43-55 ◽  
Author(s):  
J. P. Kroustrup ◽  
H. J. G. Gundersen
Author(s):  
T. Peterson ◽  
G. Sawada ◽  
B. Wyse ◽  
B. Gilchrist ◽  
A. Diani

The Ob/Ob mouse of the genetic background C57BL/6J is characterized by obesity, hyperglycemia, insulin resistance, and hyperplasia of the pancreatic beta cells. Under electron microscopy, the beta cells from this animal model display degranulation, proliferation of the rough endoplasmic reticulum, and expansion of the Golgi apparatus, all of which are indicative of a stressed pattern of insulin storage and synthesis.Ciglitazone has been reported to function as an oral hypoglycemic agent in the 0b/0b mouse. This depression of plasma glucose was associated with a significant elevation in pancreatic insulin as observed in our laboratory after six weeks of drug treatment (100 mg/kg-day incorporated into Purina Mouse Chow). Pancreatic islets of treated and age-sex matched control C57BL/6J-Ob/Ob mice were then analyzed by ultramorphology and light microscopy to determine the effect of ciglitazone on beta cells. Under electron microscopy, the pancreatic beta cells of treated mice were well granulated with rare abnormalities of the citoplasmic organelles and insulin secretory granules occupied most of the cytoplasm of the islet - cells.


Diabetologia ◽  
1974 ◽  
Vol 10 (S1) ◽  
pp. 501-508 ◽  
Author(s):  
A. A. Like ◽  
G. C. Gerritsen ◽  
W. E. Dulin ◽  
P. Gaudreau

Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).


Author(s):  
C. T. Nightingale ◽  
S. E. Summers ◽  
T. P. Turnbull

The ease of operation of the scanning electron microscope has insured its wide application in medicine and industry. The micrographs are pictorial representations of surface topography obtained directly from the specimen. The need to replicate is eliminated. The great depth of field and the high resolving power provide far more information than light microscopy.


Author(s):  
Bruce Mackay

The broadest application of transmission electron microscopy (EM) in diagnostic medicine is the identification of tumors that cannot be classified by routine light microscopy. EM is useful in the evaluation of approximately 10% of human neoplasms, but the extent of its contribution varies considerably. It may provide a specific diagnosis that can not be reached by other means, but in contrast, the information obtained from ultrastructural study of some 10% of tumors does not significantly add to that available from light microscopy. Most cases fall somewhere between these two extremes: EM may correct a light microscopic diagnosis, or serve to narrow a differential diagnosis by excluding some of the possibilities considered by light microscopy. It is particularly important to correlate the EM findings with data from light microscopy, clinical examination, and other diagnostic procedures.


Author(s):  
F. B. P. Wooding ◽  
K. Pedley ◽  
N. Freinkel ◽  
R. M. C. Dawson

Freinkel et al (1974) demonstrated that isolated perifused rat pancreatic islets reproduceably release up to 50% of their total inorganic phosphate when the concentration of glucose in the perifusion medium is raised.Using a slight modification of the Libanati and Tandler (1969) method for localising inorganic phosphate by fixation-precipitation with glutaraldehyde-lead acetate we can demonstrate there is a significant deposition of lead phosphate (identified by energy dispersive electron microscope microanalysis) at or on the plasmalemma of the B cell of the islets (Fig 1, 3). Islets after incubation in high glucose show very little precipitate at this or any other site (Fig 2). At higher magnification the precipitate seems to be intracellular (Fig 4) but since any use of osmium or uranyl acetate to increase membrane contrast removes the precipitate of lead phosphate it has not been possible to verify this as yet.


Author(s):  
Gladys Harrison

With the advent of the space age and the need to determine the requirements for a space cabin atmosphere, oxygen effects came into increased importance, even though these effects have been the subject of continuous research for many years. In fact, Priestly initiated oxygen research when in 1775 he published his results of isolating oxygen and described the effects of breathing it on himself and two mice, the only creatures to have had the “privilege” of breathing this “pure air”.Early studies had demonstrated the central nervous system effects at pressures above one atmosphere. Light microscopy revealed extensive damage to the lungs at one atmosphere. These changes which included perivascular and peribronchial edema, focal hemorrhage, rupture of the alveolar septa, and widespread edema, resulted in death of the animal in less than one week. The severity of the symptoms differed between species and was age dependent, with young animals being more resistant.


Author(s):  
Joseph E. Mazurkiewicz

Immunocytochemistry is a powerful investigative approach in which one of the most exacting examples of specificity, that of the reaction of an antibody with its antigen, isused to localize tissue and cell specific molecules in situ. Following the introduction of fluorescent labeled antibodies in T950, a large number of molecules of biological interest had been studied with light microscopy, especially antigens involved in the pathogenesis of some diseases. However, with advances in electron microscopy, newer methods were needed which could reveal these reactions at the ultrastructural level. An electron dense label that could be coupled to an antibody without the loss of immunologic activity was desired.


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