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Biomedical subjects

H W Harris

Publications and source records attributed to H W Harris.

107 records · Page 6Linked to original sources
PubMed1986

Progressive tubulointerstitial renal disease in infancy with associated hepatic abnormalities.

Clinical, pathologic, and biochemical data are reported in two male infants who had rapidly progressive renal failure, enlarged kidneys, hepatosplenomegaly, and fat malabsorption. One infant, studied prior to the onset of significant renal insufficiency, manifested renal Fanconi syndrome, hyperparathyroidism, and marked hypocalcemia. After a brief period of dialysis, both received renal transplants. Neither has clinical evidence of reoccurrence of the renal disorder in the transplant, but both still have hepatic abnormalities. Morphologic features present in both patients include a renal lesion characterized by tubulointerstitial injury with a tubulocystic component and hepatic abnormalities with bile duct proliferation, portal fibrosis, and inflammation. These cases do not readily conform to any single published diagnostic category, including nephronophthisis-congenital hepatic fibrosis or infantile polycystic kidney disease, and appear to be unique.

Biopsy↗
PubMed1986

Fluorescent markers to study membrane retrieval in antidiuretic hormone-treated toad urinary bladder.

Antidiuretic hormone (ADH) stimulation of toad urinary bladder causes fusion of intracellular vesicles called aggrephores with the apical plasma membrane of granular cells. Aggrephores contain intramembrane particle aggregates whose appearance in the apical membrane is believed to produce a large increase in its water permeability. ADH removal (ADH washout) is thought to cause the retrieval of aggrephores into granular cell cytoplasm. We studied granular cell uptake of dextran and horseradish peroxidase conjugated with fluorescein, rhodamine, or both during ADH washout. Granular cell uptake of fluorescent dextran was dependent on prior exposure to ADH, a linear function of dextran concentration, and increased by a transepithelial osmotic gradient. Immediately after removal of ADH, granular cell fluorescence was finely dispersed and located near the apical surface. Subsequently, it coalesced into larger bodies. This change was most apparent when a single bladder was subjected to two cycles of ADH stimulation and removal using a dextran containing a different fluorophore for each cycle. The ultrastructural correlate for these fluorescent patterns was identified using rhodamine-labeled horseradish peroxidase. Electron microscopy showed that after detachment from the apical membrane, label was initially in tubular-shaped vesicles near the apical surface. Later, these vesicles clustered near multivesicular bodies and transferred their label to these structures. These tubular vesicles closely resemble the morphology of aggrephores visualized by freeze-fracture electron microscopy. We conclude that these fluorescent compounds can be used as markers for the luminal contents of membrane retrieved during ADH washout and allow detailed study of its intracellular processing.

Animals↗
PubMed1986

Transepithelial water flow regulates apical membrane retrieval in antidiuretic hormone-stimulated toad urinary bladder.

Antidiuretic hormone (ADH) increases the osmotic water permeability (Posm) of toad urinary bladder. This increase is believed to be produced by fusion of intracellular vesicles called aggrephores with the granular cell apical plasma membrane. Aggrephores contain intramembrane particle aggregates postulated to be water channels. ADH-stimulated Posm is decreased by osmotic gradient exposure, which is termed flux inhibition. We studied flux inhibition by exposing ADH-stimulated bladders to various osmotic gradients. Osmotic water flow was initially proportional to the applied osmotic gradient, but Posm decreased with time. Ultrastructural and quantitative studies of endocytosis demonstrate that apical membrane retrieval was a direct function of the transepithelial osmotic gradient. Posm remained unchanged when apical membrane retrieval was blocked by incubation of bladders at 2 degrees C, or under low water-flow conditions. These effects were reversed by increases in temperature or the applied osmotic gradient. We conclude that apical membrane retrieval causes the phenomenon of flux inhibition.

Animals↗
PubMed1986

Altered immunoglobulin status in congenital nephrotic syndrome.

The serum and urine immunoglobulin concentrations of a patient with congenital nephrotic syndrome of the Finnish type (CNS) were studied during an 11 month period. The serum IgG levels were never higher than 25% and most were below 2% of normal infant values. Serum IgM levels rose to three times normal and IgA concentrations varied. The selective protein index (SPI) showed apparent selective proteinuria (SPI less than 0.06). Intravenous gamma-globulin infusions were carried out to raise serum IgG levels. The infused IgG was initially contained within the intravascular space, but within 30 hours 55% was lost in the urine. Compared to the steady state, the renal clearance of IgG showed a 20-fold increase immediately post-infusion. We conclude that children with CNS should be considered essentially agammaglobulinemic throughout the first year of life and perhaps longer. Intravenous IgG infusions provide only hours of sufficient IgG replacement due to rapid urinary losses and may be detrimental.

Agammaglobulinemia↗
PubMed1980

Structural characterization of the phosphorylation sites of human erythrocyte spectrin.

The phosphorylation sites of spectrin dimer were characterized before and after incubation of intact human red cells with [32P]orthophosphate. Phosphate measurements of unlabeled spectrin dimer show it contains 4.0 +/- 0.3 covalent protein phosphates, all located on band 2. Quantitation of the number of exchangeable phosphorylation sites in erythrocytes labeled with [32P]orthophosphate yields 3.9 +/- 0.3 phosphates/spectrin dimer, indicating that all four spectrin phosphorylation sites are metabolically active. Tryptic and chymotryptic peptide mapping reveals that the dimer contains three unique 32P-labeled tryptic peptides of approximately 4,600 (A1), 3,500 (A2), and 2,400 (B) daltons. Peptide A1 contains both phosphoserine and phosphothreonine while peptides A2 and B possess only phosphoserine. Peptides A1 and A2 remain associated after trypsinization of spectrin dimer and are only separable in detergents. All three 32P-labeled tryptic peptides are contained within a 20,000 dalton cyanogen bromide fragment which is within a 60,000 dalton staphylococcal protease phosphopeptide. All these fragments are found within a 90,000 dalton nitrothiocyanobenzoic acid phosphopeptide. The purified 20,000 dalton fragment contains no homoserine or homoserine lactone and is the COOH-terminal cyanogen bromide peptide of band 2. The isolated tryptic peptide B possesses no lysine or arginine and is presumably the COOH-terminal tryptic peptide of band 2 and the most distal phosphopeptide. Thus, the four phosphorylation sites of spectrin dimer are clustered at the extreme COOH-terminal end of band 2.

Adenosine Triphosphate↗
PubMed1980

Comparison of the phosphorylation of human erythrocyte spectrin in the intact red cell and in various cell-free systems.

Knowledge of the position and characteristics of the four spectrin phosphorylation sites (Harris, H. W., Jr., and Lux, S. E. (1980) J. Biol. Chem. 255, 11512-11520) was used to study the kinetics of spectrin phosphorylation in the intact red cell. Incubation of intact erythrocytes in the presence of [32P]orthophoshate produced a simultaneous increase in the specific activities of all the spectrin phosphorylation sites. The dephosphorylation of spectrin followed an identical pattern. Spectrin phosphate turnover in intact red cells was then quantitatively compared to isotope labeling patterns produced by phosphorylation of spectrin in various cell-free systems ("in vitro phosphorylation"). 33P-Labeled spectrin dimer, prepared by preincubation of red cells in [33P]orthophosphate, was phosphorylated by a spectrin kinase preparation (Hosey, M. M., and Tao, M. (1977) Biochim. Biophys. Acta 482, 348-357) and [gamma-32P]ATP. Under conditions where no dephosphorylation occurred as judged by loss of 33P label, 0.46 +/- 0.1 mol of 32P-labeled phosphate was incorporated/mol of spectrin dimer. The exogenous 32P label was located in a position and ratio identical with that of the endogenous 33P lebel. Similar results were obtained when the membrane-bound spectrin present in ghosts was phosphorylated using the procedure of Birchmeier and Singer (1977) J. Cell Biol. 73, 647-659). These data indicate that within the intact red cell all of the spectrin phosphates possess an identical rate of isotope exchange and approximately 90% of the spectrin phosphorylation sites are occupied. The remaining 10% may be phosphorylated in vitro by soluble or membrane-bound spectrin kinase in a pattern that is identical with that of the intact erythrocyte.

Adenosine Triphosphate↗
PubMed1980

Micro quantitative Edman manual sequencing.

A manual Edman technique is described which allows sequential quantitative determination of from 3 to 10 amino terminal residues on quantities of peptides or proteins down to one nanomole. This is achieved by a fast, efficient method of obtaining the anilinothiazolinone or phenylthiohydantoin amino acid, and quantitating by either back hydrolysis and amino acid analysis or by a new, rapid, high resolution, quasi-isocratic, high-pressure liquid chromatographic procedure. The overall method has been extensively tested successfully on both peptides and proteins of known and unknown amino-terminal sequence and the results included here. In addition, a wide variety of applications relevant to primary structure analysis such as sequencing blocked polypeptides, use of denaturing agents as coupling buffers, reduction of protein or peptide losses on consecutive sequencing and peptide mixture analysis are all incorporated in the methodology outlined.

Amino Acid Sequence↗
PubMed1980

A high-speed, quasi-isocratic high-pressure liquid chromatography system for protein sequence analysis.

A simple, of less than 20 min duration, quasi-isocratic high-pressure liquid chromatographic system designed for effective analysis of phenylthiohydantoin-amino acids derived from Edman sequencing is described. A second 30-min quasi-isocratic system is presented which may be used when sequenced samples contain extraneous 254 nm-absorbing material. Conditions affecting chromatogram reproducibility are also examined.

Amino Acid Sequence↗
PubMed1976

Midline cutaneous and spinal defects. Midline cutaneous abnormalities associated with occult spinal disorders.

Failure of separation of the neuroectoderm from the epithellal ectoderm to proceed in an orderly and complete fashion results in a wide variety of defects involving the skin, spinal cord, and cauda equina, as well as the surrounding structures of mesodermal origin. Congenital dermal sinuses occur most commonly in the lumbosacral region, are usually associated with a spina bifida, and may connect the skin directly to the spinal canal. Epidermoid or dermoid cysts may form at any point along a dermal sinus. Four types of cutaneous or subcutaneous abnormalities commonly seen associated with occult spinal disorders are abnormal hair, angioma, lipoma, and dimple. It is essential that these lesions are investigated at an early age, since surgical excision may prevent future neurologic deficits.

Adolescent↗
PubMed1974

Enzyme activity of human central nervous system myelin.

Following ultracentrifugation in sucrose and hypotonic exposure ('osmotic shock'), myelin fractions were prepared from homogenates of human centrum ovale obtained post-mortem. Non-specific esterase (NsE), succinic dehydrogenase and acid phosphatase activities were determined. One isolation procedure utilized aqueous sucrose solutions only. Other preparative technics involved addition of phosphate buffer (pH 6.6 or 8.0) or varying concentrations of calcium or magnesium ions to preparative media. The NsE activity of myelin increased greatly when electrolytes were included in these preparative solutions. Morphologic homogeneity and protein and lipid contents of myelin were similar whatever the isolation procedure.

Acid Phosphatase↗
PubMed1966

Allescheria boydii and Aspergillus fumigatus skin test antigens.

May, Lewis K. (Woman's Medical College of Pennsylvania, Philadelphia), Ralph A. Knight, and H. William Harris. Allescheria boydii and Aspergillus fumigatus skin test antigens. J. Bacteriol. 91:2155-2157. 1966.-Protein and polysaccharide fractions were extracted from culture filtrates of Allescheria boydii and Aspergillus fumigatus by the methods of Seibert and of Heidelberger, and injected intradermally into guinea pigs previously infected with these fungi. The diameter of erythema and induration was determined at 8, 24, and 48 hr. The protein and polysaccharide antigens yielded specific skin reactions in homologously infected guinea pigs. Erythema appeared at 8 hr with both the protein and polysaccharide antigens. At this time, the polysaccharide skin tests showed erythema and a central blanched wheal. A similar wheal was not observed with the protein. The erythema of the polysaccharide reaction began fading at 24 hr, whereas the protein reaction remained unchanged through 48 hr with both antigens. In guinea pigs, the area of erythema was more constant and thus easier to measure than was induration.

Animals↗
PubMedDate not supplied

Necrotizing pancreatitis during pregnancy: a rare cause and review of the literature.

Acute pancreatitis is an uncommon cause of abdominal pain during pregnancy, and rarely progresses to the necrotizing from of the disease in this clinical setting. Hyperlipidemia is an infrequent cause of acute pancreatitis. Whereas only 100 cases of hyperlipidemia-induced necrotizing pancreatitis have been reported in the literature to date, all of the cases were mild in severity and responsive to conservative medical management. Herein we present a case of life-threatening necrotizing pancreatitis, which developed in a hyperlipidemic pregnant woman and required multiple peripartum pancreatic necrosectomies. Additionally, we review the evaluation of pregnant patients with abdominal pain, the pathophysiology of hyperlipidemia-induced necrotizing pancreatitis, and the operative care of this challenging group of patients, revisiting an innovative technique for management of the retroperitoneum.

Abdominal Pain↗