Search PubMed⌕ Search

Biomedical subjects

S Moore

Publications and source records attributed to S Moore.

At least 19 recordsLinked to original sources
PubMed1992

Use of magnetic resonance imaging to analyze the performance of hollow-fiber bioreactors.

Preliminary experiments were described that demonstrate that MRI is an effective tool for the noninvasive study of hollow-fiber bioreactors. Flow-compensated velocity-encoding pulse sequences were successively applied to analyze the velocity patterns in a module operated without cells, with an artificially induced flow field perturbation. Diffusion damping pulse sequences were also used to spatially resolve regions of cell growth in a bioreactor. These experiments provide the necessary basis from which future flow and spectroscopic studies can be conducted.

Animals↗
PubMed1992

Sulfated proteoglycans of rabbit aorta: selective extraction and alternative method for glycosaminoglycan moiety analysis.

Three different solutions containing urea, guanidine hydrochloride, or a detergent mixture were used to extract proteoglycan molecules (PG) metabolically labeled with 35S from normal rabbit aortic tissue. The size distribution of whole sulfated PG and the glycosaminoglycan (GAG) compositions in the three extracts were compared and found to be characteristically determined by the type of solution used for extraction. The spectrum of sulfated PG isolated by each solution was maintained at consecutive extractions of the tissue, even if this was used after another type of solution. The extracts obtained by using the urea- or guanidine-containing solutions contained similar, rather balanced populations of large and small PG, while the detergent-containing buffer was found to preferentially extract smaller, heparan sulfate-rich aortic PG. The selectivity of various extracting solutions could be exploited to obtain preparations enriched in certain types of sulfated PG. On the other hand, one could obtain a larger variety of 35S-labeled PG from the tissue by consecutively using two solutions with different capacities of extraction. The distribution of GAG moieties among PG populations, separated by size chromatography, was investigated by one of the commonly used methods and by a new method. The standard method is based on comparison of the chromatographic profiles of the extract before and after enzymatic digestions, requiring several chromatographic runs for a sample. In the alternative method proposed, the fractions obtained after a single chromatographic separation are adsorbed onto a support membrane. Processing of the whole membrane by GAG-specific, enzymatic treatments allows simultaneous assessment of GAG types in each fraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Neuropeptide F-immunoreactivity in the monogenean parasite Diclidophora merlangi.

The localisation and distribution of neuropeptide F (NPF)-immunoreactivity (IR) in the monogenean fish-gill parasite, Diclidophora merlangi, have been investigated by whole-mount immunocytochemistry interfaced with confocal scanning laser microscopy and, at the ultrastructural level, by indirect immunogold labeling. Using antisera directed to intact synthetic NPF (Moniezia expansa, residues 1-39) or to the C-terminal decapeptide (residues 30-39) of synthetic NPF (M. expansa), immunostaining was found throughout the central (CNS) and peripheral nervous systems (PNS), including the innervation of the reproductive system. Immunoreactivity was found to be more intense using the antiserum to the C-terminal decapeptide fragment of NPF. At the subcellular level, gold labeling of NPF-IR was found exclusively over the contents of dense-cored vesicles that occupied nerve axons of both the CNS and the PNS. The distribution pattern of immunostaining for NPF mirrored exactly that previously documented for the vertebrate pancreatic polypeptide (PP) family of peptides and for FMRFamide. This finding and the results of preabsorption experiments strongly suggest that NPF is the predominant native neuropeptide in D. merlangi and that it accounts for most of the immunostaining previously obtained with PP and FMRFamide antisera.

Animals↗
PubMed1992

Enhanced incorporation of [14C]glucosamine into glycosaminoglycans of aortic neointima of balloon-injured and cholesterol-fed rabbits in vitro.

Glycosaminoglycans (GAG), which form the elementary constituent of extracellular matrix proteoglycans (PG), are implicated in the pathogenesis of atherosclerosis, mainly due to their lipoprotein binding capability and their abundance in a developing lesion during atherogenesis. However, the reasons for the increment of GAG content are poorly understood. In the present study, the influence of two well known atherogenic factors on arterial GAG synthesis were examined by estimating the incorporation of [14C]glucosamine into aortic GAG in an in vitro incubation system. Radioactivity associated with GAG was taken to represent their synthesis. GAG synthesis by neointimal tissue of rabbit aortas, 12 weeks following balloon catheter deendothelialization was measured and compared in rabbits fed a normal or 0.25% cholesterol supplemented diet for the preceding 6 weeks. In normolipaemic rabbits synthesis was found to be 12,438 +/- 173, 17,884 +/- 1390 and 15,960 +/- 1355 dpm/mg dry defatted tissue from uninjured (control), deendothelialized (DEA) and reendothelialized (REA) areas of rabbit aortas, respectively. This incorporation of radioactivity was significantly greater in hypercholesterolaemic rabbits corresponding to 13,426 +/- 239, 32,670 +/- 3077 and 27,496 +/- 3287 in the control, DEA and REA, respectively. The results demonstrated a synergistic effect of cholesterol feeding and arterial endothelial denudation in stimulating GAG synthesis. Although GAG synthesis was found to be stimulated by either cholesterol feeding or arterial injury, the stimulation by cholesterol feeding alone was only marginal. Further, results show a much higher retention of newly synthesized GAG by the tissue from REA. This study provided a possible explanation for increased GAG content in a developing proliferative lesion.

Animals↗
PubMed1992

The social context of adolescent sexuality: safe sex implications.

This study was an examination of the sexual worlds of 153 adolescents aged 15 to 18 years through the content analysis of interviews on the topics of love, romance, relationships between the sexes, sexual values and sexual behaviors. The aim was to develop more detailed descriptions of the dimension of adolescent sexuality and relate these dimensions to sexual risk, that is, the tendency to engage in unprotected intercourse, an activity which increases vulnerability to AIDS and other sexually transmitted diseases. To this end, seven themes were isolated from the interview scripts, these being permissiveness, double standards, belief about sexual control (the Id Factor), romance, regrets about permissiveness, sexual aggression, and questioning. Measures of four of these themes were constructed, and sex and sub-group differences explored, as were the relationships between themes and sexual risk. The implications of different "pathways" to sexual risk-taking were discussed.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Neuropeptide F (Moniezia expansa): localization and characterization using specific antisera.

Immunocytochemical techniques used in conjunction with confocal scanning laser microscopy (CSLM) and electron microscopy have been used to demonstrate, for the first time, the distribution of the parasitic platyhelminth neuropeptide, neuropeptide F (NPF) in the cestode, Moniezia expansa. Antisera were raised to intact NPF(1-39) and to the C-terminal decapeptide of NPF(30-39). These antisera were characterized and validated for use in both immunocytochemistry and radioimmunoassay (RIA). NPF immunoreactivity (IR) was detected using both antisera throughout all of the major components of the central and peripheral nervous systems of the worm. The pattern of NPF-IR was found to mirror the IR obtained using a C-terminally directed pancreatic polypeptide (PP) antiserum and FMRFamide antisera; blocking studies using these antisera revealed that FMRFamide and PP antisera cross-react with NPF(M. expansa). RIA of acid-alcohol extracts of the worm measured 114 ng/g using the C-terminal NPF antiserum and 56 ng/g using the whole-molecule-directed antiserum. While the C-terminally-directed NPF antiserum cross-reacts with NPF-related peptides from other invertebrates, the whole-molecule-directed NPF antiserum is specific for NPF(M. expansa). The C-terminal NPF antiserum has potential for use in the identification and purification of NPF analogues from other platyhelminth parasites.

Amino Acid Sequence↗
PubMed1992

Anaesthetic modification of regional myocardial functional adjustments during myocardial ischaemia: halothane vs fentanyl.

During myocardial ischaemia, functional compensation occurs by non-ischaemic regions of the left ventricle (LV). Anaesthetics may affect compensation by altering contractility, metabolism and perfusion. This was studied in dogs anaesthetized with fentanyl (150 micrograms kg-1 loading dose and 100 micrograms kg-1 h-1) or 0.75% and 1.5% halothane and subjected to left anterior descending artery (LAD) occlusion. After 15 min of anterior wall ischaemia, cardiac output, mean arterial pressure and LV maximum dP/dt were diminished in the 1.5% halothane but not in the 0.75% halothane or fentanyl groups. In all groups, stroke volume decreased, LV end-diastolic pressure increased and anterior wall function deteriorated (measured as systolic shortening, peak systolic intramyocardial pressure (IMP), regional wall stroke work (RSW) and slope of preload recruitable stroke work curve (Mw)) with ischaemia. Functional changes in the lateral (non-ischaemic) wall were different between groups. Regional function during occlusion in this area improved with fentanyl (mean (SEM) IMP, RSW and Mw increased by 23 (2)%, 37 (3)% and 69 (7)%, respectively), was relatively well maintained with 0.75% halothane and diminished with 1.5% halothane.

Anesthesia, Inhalation↗
PubMed1992

Investigation of evidence for anticipatory postural adjustments in seated subjects who performed a reaching task.

The paradigm for study of anticipatory postural adjustments permits investigation of the coordination of postural and voluntary components of functional movement. The purpose of this study was to investigate whether there were anticipatory postural adjustments for voluntary movement in seated subjects under clinically relevant conditions. Eight neurologically normal subjects performed a reaching task to a target placed at shoulder height, 45 degrees to the right of midline. Onsets and magnitudes of lateral and fore-aft reactive forces associated with the movement and of electromyographic (EMG) activity of the ipsilateral deltoid and external abdominal oblique and contralateral paraspinal muscles were monitored. Conditions of trunk support, reach speed, and distance reached were manipulated. Onsets of deltoid muscle EMG activity preceded onsets of postural muscle (external oblique and paraspinal) EMG activity in 70% of all trials for seated subjects in contrast to reports of EMG activity onset in the postural muscles in advance of the prime mover in standing subjects who performed a similar task. The role of the trunk musculature and the significance of reactive forces in advance of hand movement were equivocal. This study has implications for evaluation of postural instability in persons unable to stand for testing.

Adult↗
PubMed1992

In situ ultrastructural characterization of chondroitin sulfate proteoglycans in normal rabbit aorta.

We used a monoclonal antibody recognizing chondroitin sulfate (CS) to investigate by immunocytochemistry the characteristics displayed in situ by aortic proteoglycans (PG) containing CS side chains. The antibody specifically precipitated metabolically labeled PG from aortic extracts. Anti-CS specificity was also tested directly on tissue sections and was confirmed by the virtual abolition of immunolabeling on those previously digested with CS-specific enzymes. The overall CS-PG distribution assessed by light microscopy after embedding in Lowicryl KM4 by silver-enhanced immunogold recapitulated that obtained on frozen sections with immunoperoxidase. Extracellular concentrations of CS-PG were very high in the innermost regions of aorta and decreased in the media. The reaction was weak and diffuse in the adventitia. By electron microscopy, the detailed labeling of CS-PG discriminated patterns of organization at both the regional and the molecular level and enabled morphometric estimations. In relation to other components of the extracellular matrix, we found that CS-PG and elastin mutually excluded each other, while two types of CS-PG were differently associated with collagen within media or adventitia. The use of high-resolution immunodetection for the in situ characterization of aortic CS-PG could add specific information relevant to many biological processes in which these molecules have been implicated.

Animals↗
PubMed1992

Laryngeal chondrosarcomas: a clinicopathologic study of 11 cases, including two "dedifferentiated" chondrosarcomas.

Laryngeal chondrosarcomas are uncommon, and those that contain a distinct, nonchondroid, high-grade spindle cell sarcoma (the so-called "dedifferentiated" chondrosarcoma or chondrosarcoma with additional malignant mesenchymal component [CAMMC]) are extremely rare. Laryngeal CAMMC merit special attention, as CAMMC in other sites portends a poor prognosis. Eleven patients with laryngeal chondrosarcomas are reported on; 2 of these patients had CAMMC. On follow-up, 3 of the 11 patients had recurrences. The first had recurrence 4 and 11 years after tumor enucleation; that patient died disease free 2 years after salvage total laryngectomy. The second had recurrence 2 years after partial laryngectomy and was lost to follow-up after salvage total laryngectomy. The last patient recurred 13 years after partial laryngectomy and underwent salvage total laryngectomy; that patient was one of the two who developed CAMMC, and he also developed stomal recurrence of the "dedifferentiated" component 3 years after total laryngectomy. The other 8 patients are disease free after partial laryngectomy (6) or total laryngectomy (2) 10 months to 12 years later (mean: 51 months). This includes the 1 other patient with CAMMC, who is disease free 60 months after total laryngectomy. Laryngeal CAMMC has been shown, in at least one of the two patients, to be associated with a poor outcome. Patients with recurrent laryngeal chondrosarcomas do not have a poorer outcome after salvage total laryngectomy. The authors advocate partial laryngectomy if technically feasible.

Adult↗
PubMed1992

Human GM-CSF receptor alpha-chain gene is highly polymorphic but not rearranged in AML.

Acute myeloid leukaemia (AML) blast cells express haemopoietic growth factor receptors. However, their presence does not predict response to the cognate ligand in vitro. This suggests that haemopoietic growth factor receptor structure or function may be abnormal in some cases of acute myeloid leukaemia. The granulocyte-macrophage colony-stimulating factor receptor alpha-chain gene (GM-CSF-R) has recently been localised to the pseudoautosomal region of the sex chromosomes. A sex chromosome is lost in 25% of cases of AML FAB subtype M2. The loss of one allele of this gene may have some aetiological significance in AML if the other allele is altered leading to abnormal receptor structure, function or number. In this initial study, we have examined DNA from leukaemic cells of 29 patients with AML, including three with FAB subtype M2 with deletion of an X or Y chromosome for evidence of gross rearrangement of this gene. We report that although the gene is highly polymorphic for a number of restriction enzymes, we have found no evidence of gross rearrangement in AML.

Adolescent↗
PubMed1992

The detection of Philadelphia chromosome negative metaphases in long-term bone marrow cultures of the peripheral blood from patients with chronic myeloid leukemia predicts response to interferon-alpha 2a.

The cytogenetic response of 10 patients with chronic myeloid leukaemia (CML) to human recombinant interferon-alpha 2a (rhIFN alpha 2a) was compared to the Philadelphia chromosome (Ph) status of the pre-treatment peripheral blood cells after in vitro culture under long-term bone marrow culture (LTBMC) conditions. Pre-treatment light density peripheral blood cells were cultured in LTBMC on sex-mismatched irradiated allogeneic stromal layers with weekly cytogenic examination of metaphases in the non-adherent cell fraction. This was correlated with the patients' response to rhIFN alpha. Two groups of patients, five showing a cytogenetic response (responsive) and five who failed to achieve a cytogenetic response (nonresponsive) were studied. At the initiation of the LTBMCs the Ph' was found to be present in 100% of the cells analysed for nine patients and 97% for one patient. Pretreatment peripheral blood from four responsive patients demonstrated a decline in the proportion of Ph'-positive cells (Ph+) after 1 to 2 weeks in LTBMC. In contrast, peripheral blood from all the non-responsive subjects showed persistence of the Ph+ clone in 100% of the cells analysed out to a maximum of 3 to 5 weeks in LTBMC. A significant difference was observed (Fisher exact test, p = 0.023) between the two patient groups in respect to the appearance of normal clones in the nonadherent population. The presence of Ph- metaphases in LTBMC of peripheral blood cells of CML patients may predict their cytogenetic response to rhIFN alpha 2a.

Bone Marrow↗