A preliminary investigation of ROI-image reconstruction with the rebinned BPF algorithm

The reconstruction of a three-dimensional image of a specimen from a set of electron micrographs reduces, under certain assumptions about the imaging process in the microscope, to the mathematical problem of reconstructing a density distribution from a set of its plane projections.In the absence of noise we can formulate a purely geometrical criterion, which, for a general object, fixes the resolution attainable from a given finite number of views in terms of the size of the object. For simplicity we take the ideal case of projections collected by a series of m equally spaced tilts about a single axis.

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Surface ultrastructure of danazol treated rat endometrium: A SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007641x ◽

1983 ◽

Vol 41 ◽

pp. 556-557

Author(s):

R.P. Apkarian ◽

J.S. Sanfilippo

Keyword(s):

Cross Sections ◽

Reproductive Tract ◽

Preliminary Investigation ◽

Breast Disease ◽

Distal Segment ◽

Uterine Horn ◽

Female Reproductive Tract ◽

Ultrastructural Changes ◽

Cycle Phase ◽

Sprague Dawley

The synthetic androgen danazol, is an isoxazol derivative of ethisterone. It is utilized in the treatment of endometriosis, fibrocystic breast disease, and has a potential use as a contraceptive. A study was designed to evaluate the ultrastructural changes associated with danazol therapy in a rat model. The preliminary investigation of the distal segment of the rat uterine horn was undertaken as part of a larger study intended to elucidate the effects of danazol on the female reproductive tract.Cross-sections (2-3 mm in length) of the distal segment of the uterine horn from sixteen Sprague-Dawley rats were prepared for SEM. Ten rats in estrus served as controls and six danazol treated rats were noted to have alterations of the estrus cycle i.e. a lag in cycle phase or noncycling patterns. Specimens were fixed in 3% glutaraldehyde in 0.05M phosphate buffer containing CaCl2 at pH 7.0-7.4 and chilled to 4°C. After a brief wash in distilled water, specimens were passed through a graded series of ethanol, critical point dryed in CO2 from absolute ethanol, and coated with 6nm Au. Observations were made with an IS1-40 SEM operated at 15kV.

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A Comparison of the Ultrastructural Morphology of Hepatic Necrosis in BDF1 Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099350 ◽

1981 ◽

Vol 39 ◽

pp. 586-587

Author(s):

Becky Jackson

Keyword(s):

Endoplasmic Reticulum ◽

Smooth Endoplasmic Reticulum ◽

Preliminary Investigation ◽

Hepatic Necrosis ◽

Hepatic Tissue ◽

Pronounced Increase ◽

Glycogen Store ◽

Ultrastructural Morphology ◽

Mitochondrial Integrity ◽

Glycogen Stores

Preliminary investigation has indicated similarity in hepatic ultrastructural morphology in nutritional deprivation, and cyanide induced hepatic necrosis. Analysis of hepatic tissue has indicated disruption of intracellular membranes, specifically, reduction in rough endoplasmic reticulum (RER) mitochondrial integrity, and glycogen stores. An increase in smooth endoplasmic reticulum (SER) portion was observed.To further investigate the apparent equivalence of necrotic morphology, ultrastructura1ly, BDF1 mice were subjected to senescence, nutritional deprevation, potassium cyanide (KCN) induced toxemia, and acetaminophen induced toxemia. Controls were utilized to ellucidate non-necrotic hepatocellular normals. U1trastructura1 investigation of controls (Fig. 1) shows densely granular RER, abundant glycogen stores, and morphologically normal mitochondria. Subjects with acetaminophen induced necrosis exhibit reduced normal RER with increased levels of dialated, vesicular RER in apparent conversion to SER (Fig. 2), loss of mitochondrial integrity, and glycogen store reduction. Senescent subjects exhibit a pronounced increase in SER and loss of glycogen store. (Fig. 3). Investigation of the senescent SER at high magnification (Fig. 5) indicates that the SER is arising from degranulating and vesiculating RER.

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Ultrastructural Effects of Acute Kepone Treatment in Rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010009141x ◽

1976 ◽

Vol 34 ◽

pp. 286-287

Author(s):

Richard L. Klein ◽

Åsa K. Thureson-Klein ◽

Harihara M. Mehendale

Keyword(s):

Neurological Disorders ◽

Corn Oil ◽

Preliminary Investigation ◽

Reproductive Capacity ◽

Ultrastructural Changes ◽

Lipid Deposition ◽

Severe Toxicity ◽

Sprague Dawley ◽

Ether Anesthesia ◽

Sprague Dawley Rats

KeponeR (decachlorooctahydro-1,3,4-metheno-2H-cyclobuta[cd]pentalen-2-one) is an insecticide effective against ants and roaches. It can cause severe toxicity in fishes, birds, rodents and man. Prominent effects include hepatic lipid deposition and hypertrophy, impairment of reproductive capacity and neurological disorders. Mitochondrial oligomycin-sensitive Mg2+-ATPase is also inhibited. The present study is a preliminary investigation of tissue ultrastructural changes accompanying physiological signs of acute toxicity, which after two days treatment include: pronounced hypersensitivity and tremor, various degrees of anorexia and adipsia, and decreased weight gain.Three different series of adult male Sprague-Dawley rats (Charles River or CD-I) were treated by intubation with Kepone in corn oil at a dose of 50 mg per kg for 3 successive days or at 200 ppm in food for 8 days. After ether anesthesia, rats were immediately perfused via a cannula in the left ventricle with 4% p-formaldehyde and 0.5% glutaraldehyde in Millonig's phosphate buffer at pH 7.2 for 20-30 min at 22°C.

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