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Biomedical subjects

D L Moore

Publications and source records attributed to D L Moore.

At least 55 records · Page 3Linked to original sources

Platelet-endothelial cell interactions in vitro following freeze-thaw injury or detergent treatment.

Platelet interactions with cultured bovine endothelial cells were studied following freeze-thaw damage or detergent treatment. Platelets from whole blood, platelet-rich plasma, or gel-filtered plasma did not interact directly with freeze-thaw-damaged endothelial cells. Freezing and thawing did result in the exposure of an extracellular matrix located beneath the cells, which proved very thrombogenic. Platelets from all sources attached to both microfilament and amorphous components of the extracellular matrix, although only platelets from whole blood demonstrated aggregation and extensive pseudopodia formation. Treatment of cells with Triton-X detergent resulted in exposure of an intracellular cytoskeleton. Most platelets attached to the cytoskeleton were located near the cell border and had one or more pseudopodia either in contact with extracellular or intracellular material. Adhesion of platelets to the extracellular matrix may represent platelet-collagen or platelet-fibronectin interactions since both are produced by an incorporated into the extracellular matrix. Platelet interaction with endothelial cytoskeletons may represent contact of pseudopodia with the now exposed matrix located beneath the cells. The possibility that platelets also adhered to intracellular components could not be eliminated. These findings are in agreement with data from a freeze-thaw injury model of perfused aorta. In addition, they tend to indicate that physical insult is not sufficient to induce platelet interaction with the endothelial surface, but that chemical modification enhances platelet deposition.

Adenosine Diphosphate↗

Studies on the structural basis of the heterogeneity of human prostatic and seminal acid phosphatases.

We studied possible causes of the electrophoretic heterogeneity of the acid phosphatase (EC 3.1.3.2) purified by affinity chromatography from human prostate and human seminal fluid. The isoelectric focusing pattern in polyacrylamide gel shows numerous bands in the pH range 4.0-5.2 and 5.5-5.9. Treatment with neuraminidase under conditions shown to cause complete removal of sialic acid does not abolish the observed heterogeneity. Although there is a change of the more acidic forms to ones having more basic pI values, at least 4 distinct bands remain. Structural differences at the amino terminal end can be ruled out as the cause of the remaining electrophoretic heterogeneity. Lysine is shown to be the amino terminal amino acid for both the prostatic and seminal fluid enzymes. The sequences of the first 23 amino acids are shown to be identical for the prostatic and seminal fluid acid phosphatases. The functional enzyme contains no metal ion but it can be stoichiometrically inactivated by cupric ion.

Acid Phosphatase↗

Misattribution in a fearful situation following different modes of arousal.

52 female college students were exposed to procedures expected to produce some physical or emotional arousal (viewing a sexually-explicit film or riding an exercise bicycle) and were subsequently asked to approach a snake, of which they had previously reported being afraid. Their performance was compared to that of control subjects who had been exposed to non-arousing tasks (viewing a film about sunspots or reading an article about exercise). The prediction that prior arousal would produce misattribution and reduce snake avoidance was not supported.

Adolescent↗

In vitro model for the study of platelet-vessel wall interactions following a freeze- thaw injury.

Platelet-endothelial cell interactions are important for maintaining normal hemodynamics. The intact endothelial cell lining is considered nonthrombogenic, but following disruption of the lining, platelets bind to the subendothelium. There is also much conjecture concerning the affinity of platelets for damaged endothelial cells. A model is described for the study of platelet-aorta vessel wall interactions following freeze-thaw insult. Using this model, we found that control aortas (37 degrees C) perfused with platelet-rich plasma or gel-filtered platelets showed no generalized platelet-endothelial cell interactions, although some platelets did adhere to areas of exposed subendothelium. Following freeze-thaw insult (-15 degrees or -20 degrees C), the endothelial lining was grossly disrupted. The remaining endothelium was severely damaged, demonstrating holes and pits in the plasma membranes and separation of adjacent cell borders. Platelets readily adhered to the basal lamina but were rarely noted in sole contact with the damaged endothelium. Platelet binding did not result in morphologic changes, degranulation, or aggregation. Using transmission electron microscopy, we noted platelets in contact with amorphous material and microfibrils but not collagen fibers of the subendothelium. It is concluded that this model is suitable for the in vitro study of certain hemodynamic phenomena associated with blood vessel freeze-thaw injury. In addition, freeze-thaw damage in this in vitro model indicated that platelet-vessel wall interactions were limited to areas of exposed subendothelium.

Animals↗

The detection and diagnosis of early occult and minimal breast cancer.

This article has attempted to describe the present status of efforts toward routine detection of breast cancer at a stage when it is readily curable and to point out, not only the potentials of screening programs, but also the problems and difficulties that beset them. We believe that efficient, safe screening and accurate early diagnosis are achievable and that trial directed toward this end should not only continue but expand. We see no other avenue that offers as bright a prospect for a meaningful reduction in breast cancer mortality and the monstrous toll--medical, emotional, sociologic and monetary--it exacts.

Adult↗

The Schistosoma mansoni egg granuloma: quantitation of cell populations.

Granulomas were induced by the intravenous injection of eggs of Schistosoma mansoni into the lungs of mice which were either unsensitised, sensitised by prior intraperitoneal injection of eggs, or naturally infected with S. mansoni. At various time intervals after egg injection (8, 16 and 32 days in unsensitised mice; 4, 8 and 16 days in sensitised mice; and 8 days in mice infected for 4, 8 16 and 24 wk) the lungs were removed from groups of mice and were placed in a Waring blender at low speed. Complete intact granulomas were isolated, the lesions were dispersed with collagenase and pronase and the cell populations quantified and classified as eosinophils, neutrophils and mononuclear cells less than or equal to 12 or greater than 12 micron in diameter. Small mononuclear cells consisting almost exclusively of lymphocytes were the predominant cells initially, but eosinophils became the most common cell type, reaching a peak of 71% of cells in sensitised animals 16 days after injection. Large mononuclear cells remained relatively constant at about 30% of the total cells. Neutrophils neverreached more than 10% of cells. Sensitisation by a prior intraperitoneal injection of eggs led to an acceleration of granuloma formation. In infected mice, the granulomas with the largest cell counts were seen 8 wk after infection while the smaller granulomas in the mice infected for 16 or 24 wk confirm the previously reported modulation of this immunopathological reaction.

Animals↗

Effects of autologous plasma on lymphocyte transformation in malaria and in acute protein-energy malnutrition. Comparison of purified lymphocyte and whole blood cultures.

Phytohaemagglutinin (PHA) induced lymphocyte transformation in whole blood and in purified lymphocyte cultures was investigated in Gambian children with acute Plasmodium falciparum malaria or with acute protein-energy malnutrition (PEM). Responses of purified lymphocytes cultured in the absence of autologous plasma were normal, with one exception. Autologous plasma depressed the response of purified lymphocytes to a low dose of PHA in several malaria and PEM patients. In whole blood cultures of 1 day and of 3 day duration, responses of several children with malaria or PEM were less than those of control children. Responses were not related to absolute lymphocyte counts. In 3 day, but not 1 day, cultures from control and malarious children, responses were inversely proportional to neutrophil counts. Cultures of whole blood and of purified lymphocytes in autologous plasma gave comparable results in 58 of 70 patients.

Cell Separation↗

Liver dysfunction following small-bowel bypass for obesity. Nonoperative treatment of fatty metamorphosis with parenteral hyperalimentation.

A patient with liver dysfunction following small-bowel bypass for obesity was treated successfully with intravenous hyperalimentation. The hepatic steatosis and dysfunction were most likely caused by the preferential absorption of carbohydrate in the remaining small bowel, with resulting relative protein starvation. Routine use of high-protein, low-carbohydrate diets postoperatively until weight stabilization has occurred may prevent this complication.

Adult↗

In vitro retentive strength of fixed bridges constructed with acrylic pontics and an ultraviolet-light-polymerized resin.

The in vitro retentive strength of 24 test bridges was studied. The bridges were maxillary canine to central incisor spans, and an acrylic pontic replaced the lateral incisors. The pontic was retained by a resin polymerized with ultraviolet light. The mean forces necessary to dislodge the pontic bonded to natural teeth in the three-unit bridges were determined to be 41.5 lb for a force applied toward the incisal edge and 55.8 lb for a force applied toward the gingival ridge. A promising clinical application of this technique is suggested.

Acrylic Resins↗

The detection and diagnosis of early, occult and minimal breast cancer.

Radical mastectomy as originally conceived at the turn of the century consisted of complete removal of the breast tissue, the overlying skin, the pectoral muscles, the intervening lymphatics and the axillary lymph nodes. The aim was logical but initially the results were poor. Only 41% of the 76 patients in Halsted's original series were without disease at the end of 3 years. The principal reason for this was the advanced stage of disease in the patients selected for treatment. By contrast, Gilbertsen, using clinical examination alone, surveyed women 45 years of age or older and found that of 32 patients with breast cancers detected by the screening procedure, 24 had no axillary lymph node involvement. The absolute 5-year survival rate of this group was 96%, which approaches the anticipated survival of comparable women free of breast cancer. Those with positive lymph nodes had an absolute survival rate of 75% at 5 years. Further, of 13 patients observed for 10 years, the survival rate for those without node involvement was 90% and for patients with node involvement was 33%. Patients treated at the Barnes Hospital in St. Louis between 1912 and 1933 were contrasted with similarly treated patients at the Barnes Hospital and the Ellis Fischel Cancer Hospital from 1940 to 1955. A poorer survival rate in the earlier series was related primarily to the greater frequency of advanced and larger tumors. That a significant reduction in breast cancer mortality can be achieved is becoming increasingly apparent. Among survey-detected breast cancers in the study conducted by the Health Insurance Plan of Greater New York, the 6-year mortality was half of that of controls. This reduction is even more impressive when one considers that among these patients were many with full invasive, mass-forming carcinomas at the time of initial screening. A recent report by Wanebo, Huvos and Urban discusses the treatment of prognostically favorable forms of breast cancer by modified radical mastectomy. It is possible to select from among their patients those who fit the definition of minimal breast cancer. In this group the 5-year survival rate was 97% and the 10-year survival rate was 95%. Only 1 patient died of breast cancer in 10 years. In another reported group of 65 patients with intraductal carcinoma only, there were no deaths due to breast cancer in 10 years. Should the NCI-ACS demonstration projects show, as now seems probable, that community screening programs can be effective in early breast cnacer detection, it is to be anticipated that widespread public demand for screening facilities will follow. This may present insurmountable logistic and economic problems. The total number of radiologists in the United States is not sufficient to screen annually the total population of women over age 40, or even over age 50. There is great need for the development of criteria for the ready identification of that segment of the population in which most of the cancers would be found...

Adult↗

Marginal penetration of composite resin restorations as indicated by a tracer dye.

There was no evidence of marginal penetration of a tracer dye around Class V preparations lined with a BIS-GMA sealant, filled with Nuva-fil (a composite restorative material), and covered with the sealant. In the control group, 72 per cent of the Adaptic restorations showed varying degrees of marginal penetration.

Coloring Agents↗

Arthropod-borne viral infections of man in Nigeria, 1964-1970.

During the years 1964 to 1970, 171 arboviruses of 15 different types were isolated from humans in Nigeria. Isolation rates were highest in 1969, and lowest in 1965 and 1967. Monthly arbovirus activity was highest in the rainy season months of June, July and August and lowest in the dry months of January and February. Viruses were isolated from all age groups, with the majority from children one to four years old. The viruses isolated in largest numbers were chikungunya and yellow fever, which caused epidemics in 1969, and dengue types 1 and 2 and Tataguine, which are endemic in Ibadan. Bwamba virus was isolated in 1964 and 1969, and Bunyamwera group viruses were encountered for the first time in 1969. Other viruses recovered less frequently were Zika, Igbo-Ora (an agent related to o'nyong-nyong), two viruses related to the Uganda mosquito virus Ug MP 359, Dugbe, Thogoto, Lebombo and Shuni. Several of these are new agents and have not previously been isolated from man. Clinical details are presented where available.

Adolescent↗

Depression of lymphocyte response to phytohaemagglutinin in the presence of plasma from children with acute protein energy malnutrition.

Phytohaemagglutinin-induced lymphocyte transformation of four healthy adults and a child with kwashiorkor was performed in the presence of plasma from nineteen patients with protein energy malnutrition and a nutritionally normal child. Marked inhibition occurred in the presence of plasma from six patients who subsequently died, moderate inhibition occurred in six other patients in the acute stage and in two of these six in the convalescent stage, whilst in the remaining seven there was no effect. Reduction in response did not appear to be due to plasma cytotoxicity. Plasma factors in some cases of malnutrition, associated with certain infections appear to inhibit the lymphocyte response and this may have prognostic implications.

Adult↗

A study of the influence during trituration of air-borne impurities on the strength of amalgam.

The purpose of this study was to determined the effect of air-borne gaseous impurities, introduced during trituration, on the strength of amalgams. Four experiments were conducted. Each experiment consisted of a control group (1) in which the amalgam was triturated in air and an experimental group (2) in which the amalgam was triturated in argon, an inert gas. Standard specimens yielded mean diametral tensile strengths of 5950 psi (1) and 6603 psi (2). Hand compacted specimens yielded mean diametral tensile strengths of 5829 psi (1) and 6412 psi (2). Standard specimens yielded mean compacted hydraulically yielded mean uniaxial tensile strengths of 10,928 psi (1) and 11,660 psi (2). Statistically, the differences between the means for each experiment are significant. Hence, trituration in an inert gas has been shown to be an effective method for increasing the strength of amalgam.

Air Pollution↗