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Biomedical subjects

W B Greene

Publications and source records attributed to W B Greene.

At least 91 records · Page 5Linked to original sources
PubMed1975

Effects of obstruction of cardiac lymphatics.

A study was undertaken in the dog to determine whether changes occurred in the lymphatics of the endocardium and myocardium of both ventricles after obstruction of the cardiac lymphatics. Other investigators have reported ventricular subendocardial hemorrhage, increased elastic and fibrous tissue in the left ventricle endocardium, and opacification of the mitral valve leaflets. In 14 experiments the ventricular walls were injected with India ink. The efferent cardiac lymphatics were followed to their termination in the cardiac lymph node or nodes. These nodes were excised, as were afferent and efferent lymphatic trunks. After 4 to 16 weeks, with the aid of extracorporeal circulation and oxygenation, biopsies were taken of the myocardium and endocardium of the ventricles of the beating heart. Six animals were used as control subjects. Grossly, there were no changes in the endocardium, myocardium, or valve leaflets. Light and electron microscopy demonstrated no fibrosis or elastosis, and no lymphatics were identifiable. We were unable to establish evidence of permanent changes as a result of obstruction of the lymphatics of the dog heart.

Animals↗
PubMed1975

Effects of cardiac lymphatic obstruction on coronary arteries.

A study was undertaken to determine whether changes occurred in the coronary arteries of dogs after obstruction of the cardiac lymphatics. Other investigators have described changes in the walls of coronary arteries after cardiac lymphatic obstruction that caused compromise of the lumen. Adult mongrel dogs were subjected to an operation which occluded the cardiac lymphatics. Several days later, a second operation was done to remove specimens of the terminal branches of the coronary arteries. The specimens were studied by light and electron microscopy. There was no gross or microscopic evidence of altered morphology of the coronary arterial walls.

Animals↗
PubMed1966

Histochemical demonstration of phospholipase B (lysolecithinase) activity in rat tissues.

A method has been developed for the histochemical demonstration of phospholipase B (lysolecithinase) of rat tissues. The enzyme attacks lysolecithin with liberation of 1 mole of glycerylphosphorylcholine and 1 mole of fatty acid. The recommended procedure involves use of 6-10 micro frozen sections, fixed in cold calcium-formol and incubated at 37 degrees C in Tris buffered medium at pH 6.6 containing 2.2 X 10(-3) M lysolecithin and 1% cobalt acetate. The fatty acid liberated by enzymatic hydrolysis is trapped as a cobalt precipitate and is then converted to a black-brown precipitate by treatment with dilute ammonium sulfide in cold isotonic saline. Equivalent amounts of fatty acid and glycerylphosphorylcholine are recovered by extraction and analysis of the incubated sections and of the incubation medium, thus proving that lysolecithin hydrolysis occurs under the proposed reaction conditions. Staining is reduced by treating the sections with copper ions, mercury compounds, alcohols, acetone and by heating at 60 degrees C prior to incubation with substrate. Lowering of the pH of the incubation medium has similar effect. These findings are interpreted as evidence of the enzymatic nature of the reaction. Cells exhibiting a positive staining are found in the lamina propria of the intestinal villi and crypts, in the red pulp of the spleen and in the interstitial tissue of lung, liver and thymus. Similar elements are present in bone marrow smears and in leukocyte preparations obtained by peritoneal lavage. The morphologic and staining characteristics of these cells correspond to those of the eosinophilic leukocytes. Physical and chemical agents (x-irradiation, corticosteroids) which sharply decrease the number of eosinophils also reduce the number of cells shown histochemically to hydrolyze lysolecithin. A correspondent diminution of phospholipase B activity of homogenates of the same tissues can be shown in vitro. Differences in tissue distribution and chemical properties distinguish the phospholipase B from less specific esterases and lipases.

Acetone↗
PubMedDate not supplied

Closed treatment of hip dislocation in Down syndrome.

Two young children (three hips) with Down syndrome and dislocation of the hip were successfully treated by nonoperative methods by using the principle of prolonged immobilization or bracing. A 5-year, 6-month-old patient with bilateral habitual dislocation used an ambulatory abduction orthosis full-time for 6 months and then part-time for 4 months. Complete dislocation of the right hip in a 4-year, 6-month-old patient was managed by closed reduction, spica cast immobilization for 4 months, and then an ambulatory abduction orthosis for 8 months. Both patients developed stable, well-contained hips. Nonoperative management of hip dislocation in Down syndrome can be successful and avoids the complications associated with operations previously recommended for these patients.

Braces↗
PubMedDate not supplied

Femoral neck fracture in a child with autosomal dominant osteopetrosis.

A child with autosomal dominant osteopetrosis had successful treatment of a femoral neck fracture by internal fixation. Drilling the pins into the femoral neck was extremely difficult. The histopathology in osteopetrotic bone provides a probable explanation for the technical difficulty seen in this case.

Child↗
PubMedDate not supplied

Measurement of femoral torsion: comparison of standard roentgenographic techniques with ultrasound.

Measurement of femoral torsion by ultrasound was compared with measurements by standard roentgenographic techniques in a femoral model and in a clinical study. Magilligan, Ryder-Crane, and fluoroscopic determinations on the femoral model demonstrated acceptable interobserver and intraobserver variance. With high degrees of femoral torsion, ultrasound readings were less accurate and significantly lower than the actual angle of femoral torsion. In the clinical study, ultrasound measurements were compared with Magilligan measurements in 29 hips. Similar to the model, ultrasound readings were lower and discrepancy was greater at higher angles of torsion.

Biomechanical Phenomena↗
PubMedDate not supplied

Achilles tendon lengthening in cerebral palsy: comparison of inpatient versus ambulatory surgery.

The proper use of outpatient surgery is still being defined. In similar groups of cerebral palsied children, the results of Achilles tendon lengthening were compared in those having inpatient versus outpatient surgery. No significant anesthesia or surgical complication occurred in either group, and independent ambulation in casts was achieved at similar times. Pain medication requirements (based on an analgesic potency scale) averaged 9.5 +/- 6.0 for the children having outpatient surgery compared with 25.8 +/- 22.8 for those having inpatient surgery (p less than 0.02). Outpatient Achilles tendon lengthening provides psychological and economic advantages without compromise of surgical results.

Achilles Tendon↗