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J Quinn

Publications and source records attributed to J Quinn.

At least 181 records · Page 10Linked to original sources
PubMed1988

A monoclonal antibody (anti-L-35) which reacts with human osteoclasts and cells of the mononuclear phagocyte system.

The immunohistochemical reactivity of a monoclonal antibody, anti-L-35, on a wide range of tissues is described. Anti-L-35 showed a high specificity for known and presumptive cells of the mononuclear phagocyte system including monocytes, sinus histiocytes, tangible body macrophages, interdigitating reticulum cells, Kupffer cells, alveolar macrophages, microglia, synoviocytes and Langerhans cells. Anti-L-35 also stained osteoclasts in fetal and adult bone including osteoclast-like giant cells of the giant-cell tumour of bone. Anti-L-35 did not react with any other cell type in the tissues screened apart from renal proximal tubular epithelium and megakaryocytes. This study has shown that L-35 is not restricted to activated T-cells, as previously reported, and provides further immunohistochemical evidence that monocytes, macrophages and osteoclasts contain common cellular antigens.

Adult↗
PubMed1987

Leucocyte common antigen is present on osteoclasts.

Using a large panel of monoclonal antibodies which recognize the leucocyte common antigen (LCA), the presence of LCA on osteoclasts in both fetal and adult human bone specimens has been determined by immunohistochemistry. LCA is evident on the surface of fetal human osteoclasts in bone imprints and cryostat sections. LCA was also found on osteoclasts in specimens of fixed, decalcified osteoarthritic bone. The intensity and pattern of osteoclast reactivity were similar to those of foreign-body type macrophage polykaryons in inflammatory lesions. These results favour derivation of osteoclasts and their precursors from the multipotential haemopoietic stem cell which produces peripheral blood leucocytes and argues against their origin from a separate stem cell.

Adult↗
PubMed1987

Removal of observer variability from the determination of the volume of isoflow.

The initial attractiveness of the volume of isoflow (VisoV) as an index of early small airways dysfunction has faded, perhaps because of VisoV's high variability, a significant part of which is contributed by the observer. We suggest here that the observer variability can be removed by filtering the flow data in the reciprocal volume domain, by using a modified foreign gas mixture in which some of the helium is replaced by neon, and by reading VisoV from a plot of density dependence vs. lung inflation. Support for these suggestions is drawn from both model simulations and experiments. Model simulations suggested that VisoV would be increased by the substitution of neon for some of the helium in the usual helium-oxygen (Helox) mixture. This was confirmed in tests on matched groups of normal and asymptomatic asthmatic children. The inclusion of 20% neon (Heneox20) was found to reduce the coefficient of variation in the mean value of VisoV in both groups of subjects. An interesting result of this test was that VisoV using Heneox20 was significantly higher in the asthmatic group than in the normal group, whereas VisoV using Helox was not. The results for density dependence (DD) between the 2 groups were not significantly different using Heneox20 but were using Helox. Plots of DD (derived from heavily filtered flow curves) vs. lung inflation showed an unambiguous value for VisoV.

Adolescent↗
PubMed1987

Effect of decalcification agents on immunoreactivity of cellular antigens.

The effects of several strong acids, weak acids, a proprietary decalcifier, and edetic acid on the immunohistochemical staining of cryostat and fixed paraffin embedded sections of tissue from a variety of normal and pathological calcified and uncalcified specimens were studied. Even decalcification in strong acids (HCl, HN03, 5% trichloracetic acid, HCl-edetic acid did not diminish the reactivity of many useful antigens (including leucocyte common antigen, intermediate filaments, S100 protein and epithelial membrane antigen). Weaker acids (formic acid, acetic acid) and edetic acid decalcified more slowly and generally showed greater preservation of antigenic reactivity with better morphology and staining quality. Trichloracetic acid was also useful as a quick one step fixation and decalcifying agent for both cryostat and routinely processed sections. Knowledge of the preservation of antigenic reactivity in decalcified tissue will be useful in the diagnosis of tumours of uncertain histogenesis and origin which affect calcified tissues.

Acids↗
PubMed1986

Osteoclasts contain macrophage and megakaryocyte antigens.

The origin and mechanism of formation of the osteoclast remains controversial. Although it is known to be derived from a circulating mononuclear percursor, the identity of this cell is unknown. Using a panel of monoclonal antibodies raised against macrophage and other marrow-derived cells, we determined the immunocytochemical staining of human osteoclasts in both fetal bone metaphyseal imprints and frozen sections. Osteoclasts and marrow mononuclear cells were stained by three broad spectrum antimacrophage antibodies, EBM-11, Y182a and BM2. T310, an antibody which stains macrophages and T helper cells, and C17, an antimegakaryocyte antibody, also stained osteoclasts. EBM-11, Y182a and BM2 also stained megakaryocytes in bone imprints as well as normal bone marrow smears. The presence of macrophage-associated antigens in osteoclasts, megakaryocytes and bone marrow mononuclear cells indicates that they are phenotypically similar to macrophages.

Antibodies, Monoclonal↗
PubMed1986

MRI simulator for instruction in pulse-sequence selection.

An ordinary desk-top microcomputer was programmed to simulate MR images for specified spin-echo pulse sequences. Model pixel maps of proton density and T1 and T2 relaxation times were made from published estimated values for regions of the human head, neck, and spine. Images were generated and displayed from the model maps and user-specified pulse-sequence parameters in less than 30 sec/image. Models for various pathologic conditions, including calcification, subacute hemorrhage, porencephaly, lipoma, and multiple sclerosis, were superimposed on the images of normal anatomy to create unknown cases. Simulated images can easily demonstrate the effect of pulse-sequence selection on the contrast of normal structures and pathologic conditions. Use of simulated images is an excellent technique for gaining experience in pulse-sequence selection. Low-cost microcomputers can provide adequate image detail and reasonable image display time of synthetic MR images for teaching purposes.

Computer-Assisted Instruction↗
PubMed1985

Cortisol kinetics and fluid distribution in brook trout (Salvelinus fontinalis).

Cortisol kinetics were examined in brook trout (Salvelinus fontinalis) to assess possible relationships with body fluid distribution during acclimation to sea water (SW). The disappearance curve of [3H]cortisol in plasma, after a bolus injection, was analysed by compartmental analysis using a three-pool mammillary model. The results indicated that only approximately 10% of the total exchangeable cortisol was located in the plasma pool. Over 75% of the total cortisol was associated with a large slowly exchanging pool and the remaining cortisol was located in a second extravascular tissue pool which was in rapid exchange with the plasma pool. Two days after transfer of trout from fresh water to SW, when plasma chloride concentration was at a new steady state, body weight, intracellular fluid volume, haematocrit and inulin clearance rate were lowered but plasma, blood and extracellular volumes were unaltered. Cortisol plasma clearance rate was unaltered but plasma cortisol concentration, cortisol secretion rate, total cortisol pool size and interpool transport rates were increased. These results are consistent with an acute role for cortisol in SW adaptation of brook trout. The fraction of the total cortisol cleared was smaller and the average time that cortisol spent in the tissue pools was slightly longer in trout after transfer to SW, possibly reflecting altered fluid dynamics. The fractional disappearance rate was larger at higher plasma cortisol concentrations in the SW trout. This relationship is compatible with the hypothesis that cortisol protein binding protects cortisol from metabolism.

Adaptation, Physiological↗
PubMed1985

Use of physician-hired nurses. A survey.

The results of a survey conducted on the practice of using physician-hired nurses in hospitals are reported. Nursing administrators need information on the nursing services that are being provided in direct association with the medical practice of physicians, particularly when those services influence the quality and cost-effectiveness of patient care. The information can be used to plan more effective approaches to the delivery of nursing health care services.

Educational Status↗
PubMed1984

A unique approach to performance standards for clinicians in a CMHC.

Performance standards were developed for clinicians of a large comprehensive mental health center. Clinicians were required to provide a minimum average of 20 hours of face-to-face service per week. Credit values, ranging from .5 to 3.0, were assigned for each hour of service provided based on the difficulty of the service to deliver and the amount of paperwork required. Total credits were considered as an extra accomplishment and utilized as a criterion for determining merit increases. The results indicated an increase in the utilization of family and group therapy as well as a more equitable system for evaluating widely differing services.

Community Mental Health Services↗