Biomedical subjects
J Black
Publications and source records attributed to J Black.
Laparoscopic pericardial fenestration for malignant pericardial effusion.
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Quantitative analysis of rat synaptosomes and cerebrum using high-resolution 1H magnetic resonance spectroscopy.
This study explored the utility of 1H magnetic resonance spectroscopy to study a standard synaptosomally enriched preparation (P2 pellet) made from rat cerebrum. The preparation contained high concentrations of N-acetylaspartate and gamma-aminobutyric acid and low concentrations of glutamine, indicating that they were in fact rich in neuronal cytosol. Synaptosomes contained half the lactate and glutamine of cerebrum. Alanine, aspartate, glutamate, and succinate had the same concentrations in synaptosomes and cerebrum.
Decreased neutrophil respiratory burst on exposure to cobalt-chrome alloy and polystyrene in vitro.
The effect of biomaterials on the superoxide-producing ability of neutrophils was studied. Human peripheral blood neutrophils were incubated with cobalt-base alloy (F-75) or polystyrene beads of a nonphagocytosable size. Respiratory burst activity was studied by measuring superoxide dismutase inhibitable reduction of cytochrome C. Neutrophils were found to release no more superoxide anion on incubation for up to 3 h with either material in a protein-free medium than controls without foreign material. However, the ability of neutrophils incubated with either biomaterial to subsequently respond to phorbol myristate acetate challenge was decreased (p less than 0.05). Chemical analysis of supernatants for the F-75 samples showed a high concentration of cobalt in the medium within 1 h of incubation. Minimal chromium and nickel was detected. No correlation could be demonstrated between metal in solution and the respiratory burst defect in neutrophils. Instead it appears that interaction of cells with either surface was the critical event in altering the response to phorbol myristate acetate. This observed functional defect may play an important role in rendering tissue around implanted biomaterials susceptible to infections.
Development of FRP composite structural biomaterials: ultimate strength of the fiber/matrix interfacial bond in in vivo simulated environments.
Fiber reinforced polymer (FRP) composites are being developed as alternatives to metals for structural orthopedic implant applications. FRP composite fracture behavior and environmental interactions are distinctly different from those which occur in metals. These differences must be accounted for in the design and evaluation of implant performance. Fiber/matrix interfacial bond strength in a FRP composite is known to strongly influence fracture behavior. The interfacial bond strength of four candidate fiber/matrix combinations (carbon fiber/polycarbonate, carbon fiber/polysulfone, polyaramid fiber/polycarbonate, polyaramid fiber/polysulfone) were investigated at 37 degrees C in dry and in vivo simulated (saline, exudate) environments. Ultimate bond strength was measured by a single fiber-microdroplet pull-out test. Dry bond strengths were significantly decreased following exposure to either saline or exudate with bond strength loss being approximately equal in both the saline and exudate. Bond strength loss is attributed to the diffusion of water and/or salt ions into the sample and their interaction with interfacial bonding. Because bond degradation is dependent upon diffusion, diffusional equilibrium must be obtained in composite test samples before the full effect of the test environment upon composite mechanical behavior can be determined.
Human neutrophil response to short-term exposure to F-75 cobalt-based alloy.
The effect of biomaterials on the activation of human neutrophils was studied. Human neutrophils were incubated with F-75 cobalt-based alloy or polystyrene microspheres of a nonphagocytosable size with two times total neutrophil plane surface area. Scanning and transmission electron microscope (SEM, TEM), energy dispersive x-ray microanalysis (EDX), and graphite furnace atomic absorption spectroscopy (GFAAS) were used to analyze changes in cellular morphology and metal content. This report presents evidence that human PMNs display morphological changes related to foreign material challenge, including activation on F-75 bead surfaces, pinocytosis of corrosion products, formation of intracellular vacuoles, degranulation, etc. Moreover, when PMNs were present, the corrosion release rate of F-75 increased as much as three times over cell-free controls.
Determination of three-dimensional morphometry of adherent cells by surface profilometry.
A three-dimensional, non-contacting surface profiler was used to analyse cells that had been previously prepared for scanning electron microscopy. The height of ten attached and spread cells was measured in both two- and three-dimensions (2-D and 3-D). The 2-D scan is a typical, linear profilometer output, while a 3-D image is produced with a 3-D detector. The 3-D contour plots of each cell were then compared with scanning electron microscopy micrographs by digitizing four morphological parameters: perimeter, surface area, long axis and short axis of each cell. A paired Student's t test showed that the two imaging techniques are not equivalent. Non-equivalence was attributed to a difference in the method of calibration. However, when combined with scanning electron microscopy, the profiler allowed complete three-dimensional quantitative analysis of cellular morphology.
Viral susceptibility of an immortalized human microvascular endothelial cell line.
CDC/EU.HMEC-1 is the first immortalized human microvascular endothelial cell line that retains morphologic, phenotypic, and functional characteristics of a normal human microvascular endothelial cell. This study evaluates a variety of viruses and their effects on this human endothelial cell line. The data indicate that adenoviruses, some herpesviruses, reoviruses and most picornaviruses grow well in HMEC-1, with distinctive cytopathic effects. The paramyxoviruses, however, do not appear to propagate, nor does HIV. The findings indicate that microvascular endothelial cells may act as a reservoir of these viruses; it also suggests the possibility that microvascular endothelium could be involved in the processing and presentation of antigen to immune cells.
Relapsing polychondritis--a study of four cases.
Four case reports of relapsing polychondritis, (RP), are presented, together with a literature review and management suggestions. There are approximately 211 reported cases in world literature making RP an uncommon condition associated with high morbidity and mortality rates. The key to the management of RP is based on accurate and early diagnosis though the ideal medical regimen has yet to be elucidated.
Who is winning?
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No second thoughts here.
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Managing conflict.
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Merry Christmas John.
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Writing for publication: advice to potential authors.
If you have thought about writing for publication, then take the time to read this article! Plastic Surgical Nursing Editor Joyce Black, MSN, RNC, CPSN, will discuss each step of the process, including tips on generating a topic, writing the first draft, editing your work, and submitting to a journal. Advice to authors on submitting to Plastic Surgical Nursing will also be discussed.
Sexual harassment in the workplace.
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Laparoscopic excision of an intra-abdominal testis.
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