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R L Hackett

Publications and source records attributed to R L Hackett.

At least 73 records · Page 4Linked to original sources
PubMed1979

Histologic study of the early events in oxalate induced intranephronic calculosis.

The early phases of calcium oxalate crystal formation in rat kidneys after intraperitoneal challenge with sodium oxalate were examined. From the results we conclude that the crystals are formed intraluminally in the proximal tubules of the renal cortex. The size, number, and distribution of calcium oxalate particles depend on the amount of sodium oxalate injected and the time interval after its injection. Tubular necrosis and dilation were evident after administration of higher doses of sodium oxalate. The papillary tip and corticomedullary junction were the preferential sites for crystal localization after longer periods of injections of higher doses of sodium oxalate.

Animals↗
PubMed1978

Quantitation of particles in the freeze-fractured nuclear membrane after renal ischemia.

Changes in the number and sizes of membrane-associated particles have been quantitated in the protoplasmic (P) and exoplasmic (E) fracture faces of the outer membrane of nuclei isolated from the inner cortex following renal ischemia and reflow in the rat. No changes were observed in the inner nuclear membrane. After 20-min ischemia, the number of particles in both fracture faces decreased. With reflow, the total number of particles decreased after both 20- and 60-min ischemia. The partition coefficient (Kp = CPF/CEF) increased from 10 to 11 and 17 at 20- and 60-min ischemia then fell below control values to a Kp of 7 after 120 min. After reflow, Kp steadily decreased except after 20-min ischemia followed by 240-min reflow when Kp began to rise. The sizes of particles were predominantly 60 A in the P face of control outer membranes but became larger after ischemia. After 20- and 60-min ischemia with reflow, the size distribution became more normal. The shifts in particle numbers and sizes seem to indicate modifications within the membrane resulting from ischemia.

Animals↗
PubMed1976

Tridimensional ultrastructure of freeze-fractured rat kidney cortex (studied in stereo).

The tridimensional ultrastructure of the inner cortex of rat kidney has been studied by observing freeze-fractured tissue in stereo. The complex structure of the tubules, fenestrated capillaries and glomeruli is more readily observed through the irregular fracturing of the tissue that occurs in this technique. The ultrastructure of the brush border and interdigitating membranes of the proximal tubules, the structure of the fenestrated endothelial membranes of the capillaries and the ribbon-like appearance of the filtration space between the foot processes of the glomeruli were especially well depicted in stereo images of freeze-fractured renal tissue.

Animals↗
PubMed1976

Plasma membrane changes in freeze-fractured rat kidney cortex following renal ischemia.

Ischemia was produced in the inner cortex of the rat kidney by clamping the pedicle (artery, vein, and ureter) and severing collateral connections. After 30 minutes of ischemia, a slight aggregation of membrane-associated particles was observed in the freeze-fractured plasma membranes. The aggregation was progressive after 60 and 120 minutes of ischemia. These changes were reversible after 15 and 240 minutes of reflow of blood following 30 or 60 minutes of ischemia. The changes were irreversible after 120 minutes of ischemia. The cells were vacuolated after ischemic periods of 30 minutes or longer and after 120 minutes of ischemia the tissue was severely damaged and aggregation of membrane-associated particles was evident in the vacuolar membranes. No changes in the tissue or plasma membrane were observed after 5 or 20 minutes of ischemia.

Animals↗
PubMed1975

Primary signet ring cell carcinoma of bladder exemplifying vesical epithelial multipotentiality.

The eighth reported case of primary signet ring cell carcinoma of the urinary bladder is described clinically and pathologically. It is unusual because of complete replacement of the transitional epithelium by squamous and glandular metaplasia. The latter was particularly striking, demonstrating "normal" colonic mucosa, cystitis glandularis, well-differentiated adenocarcinoma, poorly differentiated adenocarcinoma, and the rare signet ring cell carcinoma variant. The possible origin of such changes is discussed.

Adenocarcinoma, Mucinous↗