PubMed Health⌕ Search

Biomedical subjects

P L Moore

Publications and source records attributed to P L Moore.

At least 19 recordsLinked to original sources
PubMed2003

Gunshot injuries to the temporal bone.

The current incidence of missile injury to the temporal bone (MITB) is very low in the United Kingdom. However, the increasing frequency of firearm violence in Britain suggests a greater risk of occurrence. This, along with the devastating potential sequelae of MITB (facial palsy, dead ear, intracranial damage, major vascular injury and cosmetic disfigurement), requires otolaryngologists to be conversant with all aspects of their management. The risk of major complications is much higher with MITB than with temporal bone injury following blunt trauma, and surgical management is, therefore, much more common. We present one such case, and review the literature outlining the pathogenesis, clinical features, and recommended management.

Adult↗
PubMed2001

Atypical lipoma of the tongue.

We report an atypical lipoma arising in the tongue of a 43-year-old man who presented with an indolent dorsal lingual swelling. Atypical lipomas contain multivacoulated lipoblasts, which distinguishes them from benign lipomas. The superficial location in this case distinguishes this tumour from well-differentiated liposarcoma, which is biologically similar in lacking the propensity for metastasis. The superficial location of atypical lipoma allows a complete resection, which is often not possible for the deep-seated counterpart. Atypical lipoma and well-differentiated liposarcoma, if left in situ, may undergo transition to de-differentiated liposarcoma. Atypical lipoma should be completely excised with a cuff of normal tissue in order to prevent repeated local recurrence and the possibility of de-differentiation.

Adult↗
PubMed2000

Relevance of commercial diagnostic tests to detection of enteric adenovirus infections in South Africa.

The prevalence of enteric adenoviruses detected by an in-house enzyme-linked immunosorbent assay (the RIVM-ELISA) ranged from 13 to 38%, and subgroup F adenoviruses comprised 86%. All subgroup F adenoviruses reacted with both RIVM anti-adenovirus type 40 (Ad40) and anti-adenovirus type 41 (Ad41) monoclonal antibodies but were not detected by Adenoclone Type 40/41 enzyme immunoassay (EIA). The correlation between the Biotrin EIA and RIVM-ELISA results was low (26%). Immunospecific tests suggest that a significant proportion of enteric adenoviruses, possibly comprising previously unidentified or emerging types, are not detected by commercial diagnostic tests in South Africa.

Adenovirus Infections, Human↗
PubMed1997

The influence of flooring on standing balance among older persons.

This study investigated the effects of flooring on balance during quiet standing in healthy young and older participants. Seven flooring conditions were examined, including a hard tile floor and combinations of low-pile and high-pile carpet with urethane foam and rubber padding. The resulting floors provided a variety of compliant surfaces, ranging from very soft to hard. Participants stood during three separate visual conditions: eyes open, eyes closed, and looking at a moving visual surround. Three measures of postural sway were calculated using center of pressure recordings during the trails. The results showed that the amplitude of sway was higher in the older than in the younger participants, particularly in the moving visual surround condition. Flooring compliance was found to have an effect on sway during moving visual environments, with the largest effects found among the older participants. Softer floors increased the amount of sway in the older participants. These results suggest that floor compliance influences standing postural stability in older people, particularly in destabilizing visual environments.

Adult↗
PubMed1991

Dihydrotetramethylrosamine: a long wavelength, fluorogenic peroxidase substrate evaluated in vitro and in a model phagocyte.

Dihydrotetramethylrosamine, a fluorogenic substrate for peroxidase, and its fluorescent oxidation product, tetramethylrosamine chloride, were evaluated. The substrate is colorless and nonfluorescent while the oxidized dye absorbs at 550 nm and emits at 574 nm in both methanol and water. In vitro assays demonstrated that the substrate was oxidized to the fluorophore by horseradish peroxidase in the presence of hydrogen peroxide. In vivo uptake and oxidation of the substrate by Amoeba proteus was characterized by the initial appearance of fluorescent phagocytic vacuoles with subsequent localization in vesicular organelles the size and shape of protozoan mitochondria. Similar staining patterns occurred in cells incubated with substrate, oxidized rosamine or rhodamine 123, a known mitochondrial stain.

Amoeba↗
PubMed1991

Cascade blue derivatives: water soluble, reactive, blue emission dyes evaluated as fluorescent labels and tracers.

Fluorescent dyes based on the pyrenyloxytrisulfonic acid (Cascade Blue) structure were prepared and evaluated. The dyes contain functional groups that react with amines, thiols, acids, aldehydes, and ketones, forming covalently bonded, fluorescent derivatives of molecules with broad biological interest. Reactive groups in the Cascade Blue dyes include carboxylic acids and activated esters, amines, hydrazides, alcohols, photoaffinity reagents, acrylamides, and haloacetamides. The dyes exhibited absorption maxima at 374-378 nm and 399-403 nm, with extinction coefficients in the range of 1.9 x 10(4)-2.4 x 10(4) M-1cm-1 and 2.3 x 10(4)-3.0 x 10(4) M-1cm-1, respectively. Emission maxima ranged from 422-430 nm. The spectral properties of the fluorescent dyes are sufficiently different from fluorescein to permit simultaneous use of both dyes with minimum spectral interference. The Cascade Blue derivatives have narrower spectral bandwidths and smaller Stokes' shifts than other reactive dyes with similar spectral properties, do not show appreciable sensitivity to pH, have higher solubilities in aqueous solution, and have good to excellent quantum yields. Cascade Blue conjugates of a number of histochemically and biologically useful molecules were prepared, including dextrans, albumins, Fc receptor binding proteins, antibodies, lectins, membrane receptor binding proteins, and biotin binding proteins, as well as biological particles and bacteria. Cascade Blue conjugates of secondary and tertiary labels yielded specific fluorescence localization in the indirect immunofluorescent staining of human epithelial cell (HEp-2) nuclei.

Cell Line↗
PubMed1986

Vasoactive characteristics of calcitonin in coronary and hepatic circulations.

Although parathyroid hormone (PTH) has been shown to possess potent vasodilator and hypotensive properties, little information is available on the cardiovascular effects of the other major calcium-regulating peptide hormone, calcitonin. In the present studies we examined the possibility that calcitonin may be vasoactive in the coronary and hepatic circulations. In anaesthetized open-chest or open-abdomen dogs, salmon calcitonin (sCT) (0.0001-10 IU/kg), PTH-(1-34) or adenosine were injected intra-arterially via the left circumflex or common hepatic artery. Flow probes were placed proximal to the injection sites to determine blood flow rates before and after injections. The results showed that sCT was vasoactive in the dog, eliciting opposite effects on basal flow in the coronary (vasoconstriction) and hepatic (vasodilatation) circulations, but augmenting PTH-induced vasodilatation in both regions.

Animals↗
PubMed1985

Cardiovascular responses to parathyroid hormone.

The synthetic amino terminal fragment of parathyroid hormone, PTH-(1-34), is a potent coronary artery vasodilator in the dog. In the present study, using instrumented open-chest dogs, we have performed the initial characterization of this effect and showed other dose-related cardiovascular effects of the hormone. A near-maximal flow response was obtained after intracoronary injection of 0.024 nmol X kg-1 PTH-(1-34) with minor, if any, concomitant changes in mean blood pressure, contractile force, or heart rate. At higher doses, mean blood pressure decreased while contractile force and heart rate increased in dose-dependent fashion. Infusion of PTH-(1-34) for 20 min showed that the vasodilatory effect could be sustained without a concomitant decrease in mean arterial pressure. Pharmacological characterization showed for the first time that the coronary response to PTH-(1-34) was unaltered in the presence of beta- or alpha-adrenergic, muscarinic, or histaminergic blockades. We conclude that PTH-(1-34), an endogenous circulating calcemic peptide, produces a large increase in coronary blood flow at doses sufficiently low to preclude complicating effects on blood pressure, contractile force, and heart rate. Furthermore, the results suggest that the vasodilatory effects may be specific.

Animals↗
PubMed1984

X-ray microanalysis: identification and quantification of elements in normal and pathologically altered cells.

It is apparent that advanced technology in X-ray microanalysis is rapidly becoming applicable to experimental cellular pathology. Additionally, it has already proven to be of significant value in diagnostic human pathology and clinical research, especially in the areas of environmental toxicology and forensic pathology. Like routine electron microscopy, X-ray microanalysis will soon be a necessary technology for any major medical center practicing 'state-of-the-art' medicine.

Calcinosis↗
PubMed1978

Phagocytosis of bacteria by polymorphonuclear leukocytes. A freeze-fracture, scanning electron microscope, and thin-section investigation of membrane structure.

The changes in membrane structure of rabbit polymorphonuclear (PMN) leukocytes during bacterial phagocytosis was investigated with scanning electron microscope (SEM), thin-section, and freeze-fracture techniques. SEM observations of bacterial attachment sites showed the involvement of limited areas of PMN membrane surface (0.01-0.25mum(2)). Frequently, these areas of attachment were located on membrane extensions. The membrane extensions were present before, during, and after the engulfment of bacteria, but were diminished in size after bacterial engulfment. In general, the results obtained with SEM and thin-section techniques aided in the interpretation of the three-dimensional freeze-fracture replicas. Freeze-fracture results revealed the PMN leukocytes had two fracture faces as determined by the relative density of intramembranous particles (IMP). Membranous extensions of the plasma membrane, lysosomes, and phagocytic vacuoles contained IMP's with a distribution and density similar to those of the plasma membrane. During phagocytosis, IMPs within the plasma membrane did not undergo a massive aggregation. In fact, structural changes within the membranes were infrequent and localized to regions such as the attachment sites of bacteria, the fusion sites on the plasma membrane, and small scale changes in the phagocytic vacuole membrane during membrane fusion. During the formation of the phagocytic vacuole, the IMPs of the plasma membrane appeared to move in with the lipid bilayer while maintaining a distribution and density of IMPs similar to those of the plasma membranes. Occasionally, IMPs were aligned to linear arrays within phagocytic vacuole membranes. This alignment might be due to an interaction with linearly arranged motile structures on the side of the phagocytic vacuole membranes. IMP-free regions were observed after fusion of lysosomes with the phagocytic vacuoles or plasma membrane. These IMP-free areas probably represent sites where membrane fusion occurred between lysosomal membrane and phagocytic vacuole membrane or plasma membrane. Highly symmetrical patterns of IMPs were not observed during lysosomal membrane fusion.

Animals↗
PubMed1977

Granule release by polymorphonuclear leukocytes treated with the ionophore A23187.

Polymorphonuclear leukocytes (PMN's) incubate three to eight minutes at 37 degrees C in medium containing 1 X 10(-6) M of the ionophore antibiotic A23187 released their cytoplasmic granules into the extracellular medium. Transmission electron microscopy of treated cells showed microfilament bundles extending between adjacent granules within the cytoplasm and between granules and the plasma membrane. Tiny dense projections (beads) 8-12 nm in diameter were observed along segments of the cytoplasmic surface of the plasma membrane with a periodicity of 20-30 nm. These beads were observed on the plasma membrane only in the vicinity of intra- or extracytoplasmic granules. The structural relationships of the beads with the plasma membrane microfilaments suggest they play a role in the process of ionophore-induced granule release from polymorphonuclear leukocytes.

Animals↗