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B Ferris

Publications and source records attributed to B Ferris.

49 records · Page 3Linked to original sources
PubMed1972

Characterization of human platelet vascular permeability-enhancing activity.

Human platelet acid extract obtained from both whole platelets and from isolated subcellular granules was partially purified by DEAE-cellulose chromatography and Sephadex gel filtration. The heat-stable, nondialyzable cationic protein fraction with a mol wt of approximately 30,000 produced a biphasic increase in vascular permeability in rabbit skin and also had antiheparin activity. The acute (15 min) increase in vascular permeability was blocked by prior treatment of the animal with antihistamine and was characterized histologically by edema of perivascular tissues and dilation of capillaries and veinules. The delayed (3 hr) permeability effect was not blocked by antihistamine and was characterized histologically by leukocytic infiltration into the skin. The experiments described suggest that human platelet lysosomal release of cationic proteins may increase vascular permeability by several mechanisms including endogenous histamine release as well as delayed chemotaxis.

Animals↗
PubMed1971

Macrophage plasma membranes. I. Isolation and studies on protein components.

Plasma membranes have been isolated from pure populations of rabbit alveolar macrophages which were swollen in water, fixed briefly with glutaraldehyde, disrupted by Dounce homogenization, and separated by sucrose gradient centrifugation. The recovered membranes exhibited good structural preservation and enzymatic activity; both morphologic and biochemical evidence indicated a high degree of purity (>90%) of the membrane preparation. Interiorized plasma membranes were also prepared without exposure to glutaraldehyde from phagocytic vacuoles recovered from alveolar macrophages which had ingested large numbers of polystyrene spheres. These membranes were contaminated with lysosomal constituents, but they were nevertheless of value for comparison to the "pure" membranes isolated by the glutaraldehyde procedure. Acrylamide gel electrophoresis of the solubilized plasma membranes and phagolysosomal membranes revealed similar protein patterns, with seven to nine individual components ranging in molecular weight from 70,000 to 140,000. The two most rapidly migrating components gave positive reactions for lipid as well as protein. A band containing carbohydrate was detected near the origin of the plasma membrane gels. Antisera were made by injecting guinea pigs with the purified rabbit alveolar macrophage plasma membranes. Gel diffusion and immunoelectrophoretic study of these antisera established the presence of rabbit immunoglobulin G and of one or two other antigenic constituents in the membrane preparation.

Acid Phosphatase↗
PubMed1971

Macrophage plasma membrane. II. Studies on synthesis and turnover of protein constituents.

Rabbit alveolar macrophages were incubated in vitro with radioactive protein precursors. Plasma membranes were isolated from these cells, dissolved in phenol-urea-acetic acid, and separated by acrylamide gel electrophoresis. (3)H-leucine was rapidly incorporated into membrane protein. The rate of labeling with (3)H-leucine was markedly different from one protein band to another, indicating heterogeneous or multistep synthesis and assembly of proteins in the alveolar macrophage plasma membrane. Cells incubated with (3)H-choline incorporated this compound into membrane lecithin. On gel electrophoresis the label derived from choline was located in the two bands migrating most rapidly towards the cathode. Studies on cells incubated with (3)H-glucosamine revealed incorporation of label into two protein bands, one located near the origin and the other migrating rapidly towards the cathode. The in vitro techniques were also employed for pulse-chase studies to gain information on rate of turnover of macrophage plasma membrane proteins. This turnover rate was rapid, with a half-life of approximately 8 hr. The radioactivity disappeared from the several protein bands at the same rate, suggesting bulk removal of membrane rather than catabolism of the individual proteins in situ. Endocytosis seems a likely mechanism to account for a major part of the plasma membrane removal. Studies on the protein components of phagolysosomal membranes from cells which had been labeled with (3)H-leucine revealed the presence of all of the major labeled protein bands characteristic of the plasma membrane except one, thus confirming the bulk interiorization of large segments or units of plasma membrane by endocytic processes.

Animals↗
PubMed1970

Increased vascular permeability produced by human platelet granule cationic extract.

A cationic protein extract obtained from isolated human platelet granules increased vascular permeability in mouse and rabbit skin. The permeability-enhancing effect was not inhibited by soybean trypsin and pancreatic trypsin inhibitor, methylsergide maleate, carboxypeptidase B, and C[unk]1 inactivator. Permeability-enhancing activity was blocked by prior treatment of challenged animals with antihistamine. The nondializable relatively heat-stable cationic granule protein extract possessed potent mastocytolytic activity. The experiments described suggest that human platelets exert a permeability-enhancing effect by lysosomal release of cationic proteins which cause histamine release from adjacent tissue mast cells.

Animals↗
PubMed1969

Studies on human platelet protease activity.

SOLUBILIZED PROTEIN DERIVED FROM HUMAN PLATELETS WAS FRACTIONATED BY DEAE CELLULOSE COLUMN CHROMATOGRAPHY AND ANALYZED FOR PROTEASE ACTIVITY USING THREE SUBSTRATES: denatured bovine hemoglobin, alpha casein, and purified plasminogen-free human fibrinogen. A protein fraction was found with proteolytic activity which was heat labile and not attributable to plasmin. The activity was not potentiated by cysteine or inhibited by iodoacetamide. Studies of pH optima indicated a broad range of enzyme activity with peaks in both the acid and alkaline region. Cathepsin A activity was detected in the platelet protease fraction by hydrolysis of the synthetic substrate N-carbobenzoxy-alpha-L-glutamyl-L-tyrosine. Similar proteolytic activity was found when the proteins derived from isolated platelet granules were examined. The results indicate that human platelets possess potent intracellular proteolytic enzymes. The relationship of this proteolytic activity to the hemostatic process is discussed.

Blood Coagulation↗
PubMedDate not supplied

The health effects of automobile exhaust. VI. Relationship of respiratory symptoms and pulmonary function in tunnel and turnpike workers.

To examine the effect of automobile exhaust on respiratory symptoms and pulmonary function, the authors studied 175 tunnel and turnpike workers employed by the Massachusetts Turnpike Authority on two occasions 3 yr apart beginning in 1972. A standard respiratory symptom and illness questionnaire was administered, spirometry was performed, and proximal hair lead and blood lead content were measured as biologic indices of automobile exhaust exposure. One hundred nine (63%) workers were current cigarette smokers, 41 (23%) were exsmokers, and 24 (14%) had never smoked. Smoking was strongly related to respiratory symptoms of cough (P less than .001) and phlegm production (P less than .001), but not to wheezing (P = .41), breathlessness (P = .14), bronchial asthma (P = .13), or frequent chest colds (P = .14). When workers were stratified by smoking status, no effect could be seen between high automobile exhaust exposure as measured by a variety of parameters and all of the above respiratory symptoms and illnesses. The level of pulmonary function [forced expiratory volume in 1 sec (FEV1.0) and forced vital capacity (FVC)] was not related to past or current exhaust exposure in a cross-sectional analysis when we controlled for age, height, and cigarette consumption. In a prospective analysis of 84 of these workers, the observed changes in FEV1.0 and FVC over 3 yr were unrelated to exhaust exposure after controlling for age, height, cigarette consumption, and initial level of pulmonary function.

Adult↗
PubMedDate not supplied

Congenital hip dislocation or dysplasia with subluxation: a radiologic study.

We studied the behavior of hips in congenital hip dislocation. Two types were identified: those that developed normally after closed reduction and those that required an osteotomy. Children with hips that required an osteotomy were older at presentation and at follow-up had worse subluxation, with shallower acetabula. In this group, the younger the age at which reduction was achieved, the less the residual subluxation of the hip at follow-up. The age at which the late osteotomy was performed did not appear to affect the residual hip subluxation or the acetabular development. We could not find any radiologic parameter that would predict the need for an osteotomy.

Child, Preschool↗
PubMedDate not supplied

The orthopaedic management of hypophosphataemic rickets.

The orthopaedic management of 19 patients with hypophosphataemic rickets was reviewed. Three groups of patients could be identified: teenagers or young adults without knee problems, those with knee problems, and adults or elderly patients with stiff joints due to mineralisation of ligaments. Osteotomies were best staged. Diaphyseal osteotomies were performed at all ages with stabilisation over an intramedullary nail; metaphyseal osteotomies were most successful at or close to maturity. Early degeneration of the knees with shedding of the articular cartilage was seen in young adults, and osteochondritis-like lesions were seen in some teenagers. Stiffness and bone pain were a feature in elderly patients.

Adolescent↗