Effective Plasma Flow of the Individual Kidney. Determination on the Basis of the [131I]Hippuran Renogram

1972 ◽  
Vol 30 (4) ◽  
pp. 395-403 ◽  
Author(s):  
N. Norman
Keyword(s):  
1988 ◽  
Vol 11 (4) ◽  
pp. 313-316 ◽  
Author(s):  
G.M. Frascà ◽  
A. Buscaroli ◽  
L.C. Borgnino ◽  
A. Vangelista

This study analyses 75 membrane plasma exchanges carried out in 18 patients where various amounts of heparin were used to define the heparin kinetic during plasma exchange and the appropriate anticoagulation. A specific assay was employed to measure heparin concentration. Our results showed that: 1) the heparin distribution volume exceeded the expected value by 10 to 25%; 2) the drug is filtered with a sieving coefficient = 1; 3) the appropriate concentration range is within 0.2 and 0.5 Ul/ml.; 4) the heparin blood levels strictly correlate with a PTT (p<0.001); 5) the individual need for heparin is related to the patient Hct (p<0.001) and plasma flow (p<0.001). Simple quidelines are provided to determine the appropriate heparin dosage in single patients.


PEDIATRICS ◽  
1959 ◽  
Vol 23 (6) ◽  
pp. 1115-1124
Author(s):  
Norman Kretchmer ◽  
William A. Dickinson ◽  
Helen McNamara ◽  
Richard Karl

Primary aldosteronism has provoked a great deal of interest since first described. Many recent reviews of this subject have been published. Consequently the literature is not reviewed extensively here. [See FIG. 8, FIG. 9, FIG. 10 In Source PDF] Hypertension in the pediatric age period is exceedingly important because this diagnosis implies a rather poor prognosis. However, an individual with primary aldosteronism has a form of hypertension which is curable, making the diagnosis of this discase imperative. In this particular case, a 9-year-old boy was seen for a routine school examination at which time hypertension was discovered. The diagnostic procedures were designed for the consideration of disorders of the central nervous system, kidneys, ability for psychologic adjustment, cardiovascular system and, finally, of the endocrine system. In this patient there were coexistent findings of pyelonephritis and primary aldosteronism. From all the evidence presented, it is reasonable to conclude that there was hypersecretion of aldosterone by the adrenal glands of this boy since early infancy. Hypokalemia is associated with increased secretion of aldosterone and has also been shown to predispose the individual to pyelonephritis. Also it is well known that, in the presence of hypokalemia, the kidney is unable to concentrate urine. In view of the facts that the major histopathologic effects of hypokalemia are seen in the collecting tubule and concentration of urine occurs in this part of the nephron, it is possible to assume a direct association. Since surgery, hypokalemia has disappeared and with it so has the polyuria. There has also been improvement in renal concentrating ability, glomerular filtration rate and urea clearance. The renal plasma flow and the ability of the kidney to respond to vasopressin have not yet improved. It is possible that there exists permanent scarring of the kidney and that this is reflected [See FIG. 11. In Source PDF] in depressed renal plasma flow. Similar to the well-documented study of van Buchem and co-workers, who studied an adolescent with primary aldosteronism, there was no evidence of muscular weakness in this case associated with the hypokalemia. Because only a subtotal adrenalectomy was performed, the patient is leading a completely normal life free of medication and the dangers attendant to adrenal insufficiency. Rough measurement of the urinary excretion of other steroid compounds indicates that they are present in amounts expected for the normal child. He has had mild infections since discharge; during none of these has the patient required therapeutic support. Because of the viability of the remaining adrenal tissue it is expected that he will pass through a normal pubescence and adolescence. Finally, it is standard procedure during the investigation of an individual with hypertension to test for the presence of pheochromocytoma. Since 1932, in this hospital there has not been one pheochromocytoma discovered in an individual below the age of 14 years. It is our opinion that it certainly is equally as important to consider seriously the possibility of primary aldosteronism in every child admitted to the hospital with a diagnosis of essential hypertension, because hypertension in children due to primary aldosteronism, as shown in the present report, is a curable disease.


Author(s):  
C.N. Sun

The present study demonstrates the ultrastructure of the gingival epithelium of the pig tail monkey (Macaca nemestrina). Specimens were taken from lingual and facial gingival surfaces and fixed in Dalton's chrome osmium solution (pH 7.6) for 1 hr, dehydrated, and then embedded in Epon 812.Tonofibrils are variable in number and structure according to the different region or location of the gingival epithelial cells, the main orientation of which is parallel to the long axis of the cells. The cytoplasm of the basal epithelial cells contains a great number of tonofilaments and numerous mitochondria. The basement membrane is 300 to 400 A thick. In the cells of stratum spinosum, the tonofibrils are densely packed and increased in number (fig. 1 and 3). They seem to take on a somewhat concentric arrangement around the nucleus. The filaments may occur scattered as thin fibrils in the cytoplasm or they may be arranged in bundles of different thickness. The filaments have a diameter about 50 A. In the stratum granulosum, the cells gradually become flatted, the tonofibrils are usually thin, and the individual tonofilaments are clearly distinguishable (fig. 2). The mitochondria and endoplasmic reticulum are seldom seen in these superficial cell layers.


Author(s):  
Anthony J. Godfrey

Aldehyde-fixed chick retina was embedded in a water-containing resin of glutaraldehyde and urea, without dehydration. The loss of lipids and other soluble tissue components, which is severe in routine methods involving dehydration, was thereby minimized. Osmium tetroxide post-fixation was not used, lessening the amount of protein denaturation which occurred. Ultrathin sections were stained with 1, uranyl acetate and lead citrate, 2, silicotungstic acid, or 3, osmium vapor, prior to electron microscope examination of visual cell outer segment ultrastructure, at magnifications up to 800,000.Sections stained with uranyl acetate and lead citrate (Fig. 1) showed that the individual disc membranes consisted of a central lipid core about 78Å thick in which dark-staining 40Å masses appeared to be embedded from either side.


Author(s):  
Anthony A. Paparo ◽  
Judith A. Murphy

The purpose of this study was to localize the red neuronal pigment in Mytilus edulis and examine its role in the control of lateral ciliary activity in the gill. The visceral ganglia (Vg) in the central nervous system show an over al red pigmentation. Most red pigments examined in squash preps and cryostat sec tions were localized in the neuronal cell bodies and proximal axon regions. Unstained cryostat sections showed highly localized patches of this pigment scattered throughout the cells in the form of dense granular masses about 5-7 um in diameter, with the individual granules ranging from 0.6-1.3 um in diame ter. Tissue stained with Gomori's method for Fe showed bright blue granular masses of about the same size and structure as previously seen in unstained cryostat sections.Thick section microanalysis (Fig.l) confirmed both the localization and presence of Fe in the nerve cell. These nerve cells of the Vg share with other pigmented photosensitive cells the common cytostructural feature of localization of absorbing molecules in intracellular organelles where they are tightly ordered in fine substructures.


Author(s):  
William W. Thomson ◽  
Elizabeth S. Swanson

The oxidant air pollutants, ozone and peroxyacetyl nitrate, are produced in the atmosphere through the interaction of light with nitrogen oxides and gaseous hydrocarbons. These oxidants are phytotoxicants and are known to deleteriously affect plant growth, physiology, and biochemistry. In many instances they induce changes which lead to the death of cells, tissues, organs, and frequently the entire plant. The most obvious damage and biochemical changes are generally observed with leaves.Electron microscopic examination of leaves from bean (Phaseolus vulgaris L.) tobacco (Nicotiana tabacum L.) and cotton (Gossipyum hirsutum L.) fumigated for .5 to 2 hours with 0.3 -1 ppm of the individual oxidants revealed that changes in the ultrastructure of the cells occurred in a sequential fashion with time following the fumigation period. Although occasional cells showed severe damage immediately after fumigation, the most obvious change was an enhanced clarity of the cell membranes.


Author(s):  
D. E. Becker

An efficient, robust, and widely-applicable technique is presented for computational synthesis of high-resolution, wide-area images of a specimen from a series of overlapping partial views. This technique can also be used to combine the results of various forms of image analysis, such as segmentation, automated cell counting, deblurring, and neuron tracing, to generate representations that are equivalent to processing the large wide-area image, rather than the individual partial views. This can be a first step towards quantitation of the higher-level tissue architecture. The computational approach overcomes mechanical limitations, such as hysterisis and backlash, of microscope stages. It also automates a procedure that is currently done manually. One application is the high-resolution visualization and/or quantitation of large batches of specimens that are much wider than the field of view of the microscope.The automated montage synthesis begins by computing a concise set of landmark points for each partial view. The type of landmarks used can vary greatly depending on the images of interest. In many cases, image analysis performed on each data set can provide useful landmarks. Even when no such “natural” landmarks are available, image processing can often provide useful landmarks.


Author(s):  
B. Carragher ◽  
M. Whittaker

Techniques for three-dimensional reconstruction of macromolecular complexes from electron micrographs have been successfully used for many years. These include methods which take advantage of the natural symmetry properties of the structure (for example helical or icosahedral) as well as those that use single axis or other tilting geometries to reconstruct from a set of projection images. These techniques have traditionally relied on a very experienced operator to manually perform the often numerous and time consuming steps required to obtain the final reconstruction. While the guidance and oversight of an experienced and critical operator will always be an essential component of these techniques, recent advances in computer technology, microprocessor controlled microscopes and the availability of high quality CCD cameras have provided the means to automate many of the individual steps.During the acquisition of data automation provides benefits not only in terms of convenience and time saving but also in circumstances where manual procedures limit the quality of the final reconstruction.


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