Search PubMed⌕ Search

Biomedical subjects

W B Greene

Publications and source records attributed to W B Greene.

At least 73 records · Page 4Linked to original sources
PubMed1984

Isokinetic torque levels in hemophiliac knee musculature.

The purposes of this study were to 1) measure peak torques generated by knee extensors and flexors in hemophilia patients; 2) describe flexor to extensor; 3) record the point in the arc of motion where peak torque was achieved; 4) correlate results with age, degree of hemophilic arthropathy, and presence of flexion contracture; and 5) compare results with reports on healthy subjects. Forty-seven patients (94 knees) with severe hemophilia were tested with a Cybex II isokinetic dynamometer at a speed of 30 degrees per second. Height, weight, thigh girths, and passive knee range of motion were recorded. Standing roentgenograms of the knee were evaluated to assess degree of arthropathy. Subjects were divided into groups by age and degree of arthropathy. Descriptive statistics were generated for all groups. Average peak extensor and flexor torque was similar for adolescents and adults. Increasing degree of arthropathy was associated with significant decreases in both extensor and flexor torque, an increase in flexor to extensor ratios and increasing knee flexion contractures. Across all groups, flexor to extensor ratios were abnormally high, particularly in patients with type IV arthropathy. The point in arc of motion where peak torques occurred did not differ significantly across groups and compared favorably with measures reported in the literature. For all ages, mean peak extensor and flexor torques were less than values reported in the literature for healthy subjects. Results of this study demonstrate the profound decrease in torque produced by knee musculature in hemophilia patients, particularly those with more severe arthropathy and knee flexion deformity.

Adolescent↗
PubMed1984

Effects of substituted dithiocarbamates on the testicular toxicity of cadmium.

Five substituted dithiocarbamates were evaluated for effectiveness in protecting mouse testes following administration of an LD100 dose of CdCl2 X 2.5 H2O (Cd). Toxicologic responses were assessed by light microscopic, electron microscopic, and computerized image analysis techniques. Diethyldithiocarbamate (DDTC) was the most effective antagonist. N-ethyl-N-hydroxyethyldithiocarbamate (EHDC), N-methyl-N-hydroxyethyldithiocarbamate (MHDC), and dimethyldithiocarbamate (DMDC) were moderately to minimally effective, while di-(hydroxyethyl)dithiocarbamate (DHDC) afforded no protection. Degenerative changes increased progressively in severity as the time interval between administration of Cd and DDTC was increased, but remained minimal when DDTC was given as late as two hours after Cd.

Animals↗
PubMed1983

Use of continuous passive slow motion in the postoperative rehabilitation of difficult pediatric knee and elbow problems.

Continuous passive slow motion (CPSM) was used to aid postoperative rehabilitation in seven difficult pediatric knee and elbow problems. Four patients had joint erosion secondary to hemophilic arthropathy and three patients had joint irregularities associated with long-standing limitation of joint movement. CPSM was started soon after surgery at the slow speed of 1 revolution every 12.5 min. The early, slow mobilization did not cause pain and established an arc of joint motion before intraarticular adhesions became a problem. Compared with a similar group not using CPSM, our hemophilia patients did not require postoperative manipulation, had decreased hospitalization time, and gained a greater range of motion. The group with long-standing limited joint mobility exhibited maintenance and in most cases improved motion after surgery. Thus CPSM after surgery enhances the rehabilitation process of difficult pediatric knee and elbow problems.

Child↗
PubMed1983

A modified isokinetic strengthening program for patients with severe hemophilia.

A modified isokinetic strengthening program for the knee flexors and extensors was evaluated in 32 patients with severe hemophilia. The program was effective in significantly strengthening the knee flexors and extensors; it did not increase the number of knee hemarthroses; and it could be done at home without special equipment. The greater increases in extensor and flexor strength among adolescents and adults were associated with less severe arthropathy, a 1 cm increase in thigh girth, and a greater number of days on which the exercises were done.

Adolescent↗
PubMed1983

The management of musculoskeletal problems in hemophilia. Part I. Principles of medical management of hemophilia.

Musculoskeletal bleeding in general and arthropathy in particular are the central problems among many in the two major forms of hemophilia: classic hemophilia, caused by factor VIII deficiency, and Christmas disease, caused by factor IX deficiency. Currently available replacement therapy, if properly used in a multidisciplinary setting, should provide significant benefit to hemophilic patients despite its cost and occasional complications.

Anemia, Hemolytic↗
PubMed1982

Surgery for scoliosis in congenital factor VII deficiency.

A patient with severe congenital factor VII deficiency had an anterior and posterior spine fusion for severe scoliosis. For both operations, hemostatic management was 50 units of prothrombin complex concentrate (Konyne) per kilogram of body weight before surgery and every eight hours after surgery for the first 24 hours. Subsequently, 10 mL/kg of fresh frozen plasma was given daily for five days. No bleeding problems were encountered. A treatment protocol is outlined for replacement therapy management during surgery for patients with severe factor VII deficiency. Managing hemostatic control during surgery in patients with severe factor VII deficiency is relatively easy.

Adolescent↗
PubMed1982

Simultaneous fracture of the scaphoid and radius in a child.

A 15-year-old boy sustained an ipsilateral scaphoid and radius fracture, a combination of injuries that has only received brief mention in previous reports. Closed reduction and cast immobilization produced a satisfactory result. The distal radius injury was a comminuted fracture with a vertical component that extended to the physis without involvement of the epiphysis. The mechanism of injury may have been a severe impact delivered to the base of the hand with the wrist fixed in dorsiflexion, a force that would make a distal radial epiphyseal fracture unlikely.

Adolescent↗
PubMed1982

Partial foot amputations in children. A comparison of the several types with the Syme amputation.

We compared the results in fourteen children in whom part of the foot was amputated with the results in a similar group of patients who had a Syme amputation. Based on levels of activity, physical examination, prosthetic requirements, ratio of the length of the fore part of the foot to the hind part, and gait mechanics, we classified the children into three groups. In Group I (patients with a metatarsal ray or transmetatarsal amputation) the results were clearly superior to those in the group with Syme amputation. In Group II (patients with a Lisfranc, mid-tarsal, or Chopart amputation and no equinus contracture) the patients had better over-all function but needed to make greater adjustments for gait than did those with a Syme amputation. In Group III (patients with a Chopart amputation who had an equinus contracture and inadequate length of the fore part of the foot) the results were clearly inferior to those of patients with a Syme amputation.

Adolescent↗
PubMed1982

Intratubular calcium phosphate deposition in acute analgesic nephropathy in rabbits.

Earlier chronic studies using both animal and human autopsy material have suggested that the initial lesion of analgesic nephropathy is papillary necrosis with secondary cortical interstitial nephritis. The present study was designed to define ultrastructural changes in renal tubules exposed to high levels of analgesics. Female New Zealand White rabbits were given 5-7 g APC and sacrificed after periods of 6 to 36 hours. As early as 6 hours after treatment, hydroxyapatite crystallite aggregates were seen impacted in Segment III (straight segment) of the proximal tubule at the cortico-medullary junction. Ultrastructural changes included selective calcification of the brush border, mitochondrial calcification, and peroxisomal changes. It was concluded, on the basis of ultrastructural changes, that calcification of altered tubular cells may be an initial event in analgesic nephropathy.

Analgesics↗
PubMed1982

Traumatic bowing of the forearm in an adult.

A 24-year-old woman sustained a low-velocity, continuous pressure injury to the right forearm from a conveyer belt machine. The accident caused bowing of the radius and ulna, an injury not previously reported in adults. A closed manipulation with the patient under general anesthesia required considerable force to obtain partial reduction of the radial bowing and almost complete correction of the ulnar bowing. Follow-up examination at two years demonstrated no loss of position but persistent radial bowing. The injury is a good illustration of plastic deformation in bone which is a rare condition in adults due to the elastic properties of bone and typical fracture mechanics.

Accidents, Occupational↗
PubMed1981

Effects of prolonged exposure to dietary DDT and PCB on rat liver morphology.

Livers from mature female rats exposed for up to 36 weeks to dietary levels of Aroclor 1242 (75 or 150 ppm) and/or commercial grade DDT (75 to 150 ppm) were compared to those from animals receiving basal diets. In earlier studies, reproductive effects of the test substances were assessed. Moreover, the markedly abnormal gross appearance of the livers led to examination of the hepatic effects of PCB and DDT in more detail, at both the light microscope (LM) and electron microscope (EM) levels. Light microscopy revealed focal liver cell necrosis in rats fed PCB, DDT, and PCB-DDT combinations. Higher levels of PCB (150 ppm) increased the severity of necrosis. Feeding both DDT and PCB produced similar effects at 75 ppm, and caused atypical centrolobular regeneration, occasionally forming nodules, resembling small tumors. The experimentally induced injury was associated with the marked accumulation of iron-containing pigment in hepatocytes and Kupffer cells. Electron micrographs demonstrated the presence of whorl structures (myelin figures) within liver cell cytoplasm, and for the first time clearly illustrated the endocytotic expulsion of these membranous whorls from hepatocytes into the bile canaliculi and sinusoids. Other ultrastructural changes were similar to those previously reported in rats livers injured by several hepatotoxic substances. Mitochondria enclosed by or projecting into large non-lipid vacuoles were present in several experimental groups. The electron micrographs provide the most convincing evidence to date to support the hypothesis that myelin figures may be the vehicle whereby the cells rids itself of specific hepatotoxic substances.

Animals↗
PubMed1979

Host-tumor interactions: basis for the anemia in rats bearing the hepatoma 7777.

A significant anemia develops in Buffalo rats bearing the Morris hepatoma 7777. By indiceal measurements the red blood cells (RBCs) appear to be microcytic and hypochromic. Ferrokinetic studies demonstrate a decreased uptake of iron in the bone marrow and an increased incorporation of iron in the spleens of the tumor-bearing animals. RBC survival studies indicate the presence of a hemolytic component which appears to contribute to the anemia. The RBCs from tumor-bearing animals (T-RBC) have a greatly increased fragility in sodium chloride solutions. Inspection of these T-RBCs by electron microscopy demonstrates significant echinocytosis when they are compared to normal cells. Electrophoretic separation of the hemoglobin from T-RBCs shows a pattern different from normal cells and consistent with the pattern described for hemoglobin from spleen and bone marrow. The findings are consistent with bone marrow inadequacy and an increased splenic erythropoiesis which is insufficient to maintain normal hematological values. The hypothesis is presented that the RBCs synthesized under these circumstances appear in the circulation with an "immature" hemoglobin pattern and are hemolyzed more readily. This process then contributes to the hemolytic component and development of the anemia.

Anemia↗
PubMed1979

Structural changes in a porcine xenograft after implantation for 105 months.

Morphologic studies including light microscopy and transmission and scanning electron microscopy were performed on a formaldehyde-fixed porcine xenograft prosthesis that functioned well for 8 years and had been implanted for 105 months in the tricuspid valve position. It is the oldest implanted valve studied in this manner. Although all leaflets had some gross deterioration, only one had adherent thrombus. The degenerative changes in the connective tissue from all leaflets were similar to those recently reported in glutaraldehyde-fixed porcine valves implanted for shorter periods. The surfaces of the two nonthrombosed leaflets and small portions of the surface of the thrombosed leaflet were endothelized, and the endothelium appeared to have little or no effect on the degenerative changes in the subjacent connective tissue. Further, the endothelium did not extend over the examined portion of the synthetic anulus of the prosthesis, suggesting that its origin was possibly from cells circulating in the blood.

Adolescent↗
PubMed1979

Selective mitochondrial degeneration in renal tubules following hyperbaric oxygen exposure.

To study the ultrastructural effects of hyperoxia on the kidney, young adult Sprague Dawley rats were exposed to 3 atmospheres absolute (ATAs) of pure oxygen for 5 hours and were killed in a time sequence varying from immediately to 30 days after exposure. Their renal cortices were processed for electron microscopy. Selective mitochondrial changes were observed within sublethally and transiently altered proximal tubular epithelial cells. The most consistent finding was the accumulation of 0.08 mu to 0.5 mu round to ovoid homogeneous matrical inclusions which frequently formed larger confluent amorphous masses. The inclusions stained intensely with lead and uranium but appeared homogeneously electron-lucent in unstained sections. Energy-dispersive x-ray analysis revealed that they did not contain calcium or phosphorus. The inclusions were different from the innately electron-opaque flocculent densities commonly found in pathologically altered mitochondria. Since the mitochondria containing them were removed by autophagocytosis, it is suggested that the inclusions were associated with selective mitochondrial degeneration induced by hyperoxia. No glomerular lesions were found.

Animals↗
PubMed1979

Hemochromatosis caused by excessive vitamin iron intake.

Rare cases of hemochromatosis have been reported in patients who underwent prolonged oral iron therapy for hemolytic anemia or prolonged self-treatment with iron pills. A proportionately large segment of the South African Bantu tribe, who ingest large quantities of an alcoholic beverage brewed in iron pots, are found to have the disease. Reports of health fadists developing hemochromatosis due to excessive dietary iron intake, however, are extremely rare. This report presents clinical considerations and pathologic findings in a compulsive health fadist who consumed large numbers of vitamins containing iron. Clinical findings included the development and progression of cirrhosis of the liver, bronzing of the skin, and diabetes mellitus, all consistent with a diagnosis of hemochromatosis. Light microscopy of liver biopsies taken late in the course of the disease revealed a massive buildup of iron in the hepatocytes, less in the Kupffer cells, and sparse deposition in the epithelial cells of the bile duct. Minimal periportal fibrosis was noted. Electron microscopy showed numerous pleomorphic siderosomes with varying degrees of crystallization and ferritin attached at uniform intervals to the membranes of residual bodies. Abundant free ferritin was observed in most cells. The aggregated and membrane-associated ferritin was verified by non-dispersive x-ray analysis. An additional finding, noted only by electron microscopy, was the presence of many fat-storing cells of Ito, which are thought to be involved in the onset of fibrosis.

Cytoplasmic Granules↗