Search PubMed⌕ Search

Biomedical subjects

V G Lockard

Publications and source records attributed to V G Lockard.

At least 37 records · Page 2Linked to original sources
PubMed1979

Adult rhabdomyoma of soft palate.

A case of adult rhabdomyoma of the soft palate in a 60-year-old man studied by methods including electron microscopy, is reported. The patient was free of recurrence 2 years later. The eleven previously documented cases of adult rhabdomyoma involving the oral cavity are reviewed. The concept that rhabdomyoma is a neoplasm rather than a hamartoma is favored. Adequate local excision appears to be curative. The differences between the cardiac and extracardiac forms of rhabdomyoma as well as between adult rhabdomyoma and especially granular-cell myoblastoma and fetal rhabdomyoma are presented.

Cell Membrane↗
PubMed1978

Decreased activity of NADPH oxidase in alveolar macrophages as a result of traumatic shock.

NADPH oxidase activity is significantly decreased in alveolar macrophages isolated from rabbits subjected to traumatic shock. In vitro studies indicate that activity of the enzyme is depressed in subcellular fractions of both resting and phagocytosing macrophages from shocked animals. Phagocytosis stimulates a twofold increase in NADPH oxidation in control alveolar macrophages, whereas NADPH oxidase activity is stimulated to a much lesser degree in macrophages from shocked animals. Results of this study suggest that the decreased activity of NADPH oxidase in alveolar macrophages from shocked animals may be associated with decreased bactericidal ability of the cells which was reported in a previous study (9).

Animals↗
PubMed1976

Alterations in rabbit alveolar macrophages as a result of traumatic shock.

Biochemical and electron microscope studies were conducted to determine the effects of traumatic shock on rabbit alveolar macrophages. Both resting and phagocytosing macrophages from the shocked animals, in comparison to comparable control macrophages, showed increased release of acid phosphatase from the cells into medium upon incubation in vitro, but decreases in the total content of acid phosphatase and beta-glucuronidase. Studies by electron microscopy showed ultrastructural alterations in macrophages from shocked animals consisting of a reduction in the number or a complete absence of lysosomes and, in some cases, increased amounts of rough endoplasmic reticulum and free ribosomes. In vitro incubation of macrophages from shocked animals with Pseudomonas aeruginosa showed that the process of bacterial ingestion was not impaired nor were the numbers of bacteria ingested decreased as compared to control macrophages. However, the ability of macrophages from shocked animals to destroy ingested bacteria appeared to be significantly altered. Extensive degradation of Pseudomonas was observed within phagocytic vacuoles of control macrophages after 15 minutes of incubation. In contrast, the majority of ingested organisms in macrophages from shocked animals showed no evidence of degradative changes.

Acid Phosphatase↗
PubMed1973

Alterations in the bactericidal ability of rabbit alveolar macrophages as a result of tumbling stress.

Bacteriologic and electron microscopic studies support observations that the degradative phase of the phagocytic process in rabbit alveolar macrophages is altered by subjecting the animals to tumbling stress. Macrophages from control and stressed rabbits have similar ultrastructural features. In vitro incubation of macrophages from stressed animals with Pseudomonas aeruginosa showed that the process of bacterial ingestion was not impaired, nor were the numbers of bacteria ingested decreased as compared to control macrophages. However, the ability of macrophages from stressed animals to kill ingested bacteria was significantly decreased. Bacterial plate counts after 30 minutes incubation showed that approximately 70% of the ingested organisms had been killed by control macrophages, whereas there was practically no kill by macrophages from stressed animals even after 90 minutes. Electron microscopy demonstrated extensive degradation of Pseudomonas within phagocytic vacuoles of control macrophages. These changes consisted of cytoplasmic swelling, clumping of nuclear material and disruption of the bacterial cell wall. In contrast, bacterial degradation was not observed within macrophages from stressed animals at any of the intervals studied (up to 90 minutes after rotation). This form of stress thus appears to deprive the alveolar macrophages of the ability to destroy ingested microorganisms, a factor which may be important to the establishment of pulmonary infections.

Animals↗
PubMed1972

Morphologic alterations in sheep after implantation of the Akutsu total artificial heart.

The present report describes morphologic alterations produced in sheep after implantation of a four-chambered total artificial heart. Two groups of sheep were studied. The first group was given no special antishock therapy and had an average survival time of 25.8 hours. Major morphologic changes produced in the first group were focal infarction and massive hemorrhage of the large and small bowel, ascites, severely altered lungs and multiple infarcts in the kidneys. The second group of sheep was given antishock therapy and showed an average survival time of 35.4 hours. Severe morphologic alterations in this group were generally absent in all organs except the lungs, which showed varying degrees of congestion, hemorrhage, edema, pneumonitis and atelectasis. Death in both of the above groups was due to development of irreversible hypotension and respiratory failure.

Animals↗
PubMedDate not supplied

Granular-cell myoblastoma of the cercum: report of a case.

A 9-mm granular-cell myoblastoma of the cecum found incidentally during appendectomy in a 17-year-old-girl is reported. Electronmicroscopic findings favor origin of the granular cells from an undifferentiated mesenchymal (fibroblast-like) cell. Review of the small number of previously reported cases revealed three involving the cecum, one each in the ascending and transverse colon and two in the rectum. Four patients were asymptomatic and their lesions were found incidentally. Three lesions simulated maligancy clinically; these patients underwent right hemicolectomy.

Adolescent↗
PubMedDate not supplied

Pentachlorophenol intoxication: report of a fatal case, with comments on the clinical course and pathologic anatomy.

A case of a 33-yr-old man who died following occupational exposure to pentachlorophenol is presented. Postmortem examination revealed cerebral edema and fatty degeneration of the viscera. Review of the literature indicates that the clinical syndrome of poisoning with the compound results from mitochondrial toxicity with derangement of aerobic metabolism.

Adult↗
PubMedDate not supplied

Unusual pigmented vesical lesion in a middle-aged woman.

Excess lipofuscin deposition in tissues is a phenomenon observed in normal aging. The amount of lipofuscin in myocardium, liver, skeletal muscle, and adnexal skin structures varies considerably with age and increases in older individuals. In addition, lipofuscin deposition occurs in association with specific, non-age-related processes; these include melanosis coli, the so-called brown bowel syndrome, and the black thyroid. Localized lipofuscinosis has also been described in the gallbladder, esophagus, and fallopian tubes. The present article adds lipofuscinosis vesicalis to the list of entities characterized by focal lipofuscin deposition. All cases have a characteristic gross appearance that is somewhat variable from entity to entity and in some cases may suggest clinically an ominous pathologic process.

Adult↗
PubMedDate not supplied

A simple technique for postembedding ultrastructural immunogold labeling.

A simple and reproducible method for postembedding ultrastructural immunogold labeling is described. Tissues are fixed in Carson-Millonig phosphate-buffered 4% formaldehyde, and then are embedded in LR White resin. Immunogold labeling of ultrathin sections is accomplished by means of an indirect method that employs a nonconjugated primary antibody and gold particles conjugated to antibody to immunoglobulin G. Technical aspects of fixation, embedding, and immunolabeling that influence the success of this protocol are discussed.

Antibodies↗