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S Moore

Publications and source records attributed to S Moore.

At least 253 records · Page 14Linked to original sources
PubMed1988

The plasma proteases, thrombin and plasmin, degrade the proteoglycan of rabbit aorta segments in vitro: an integrated ultrastructural and biochemical study.

The effects of plasmin and thrombin on the proteoglycan component of uninjured and deendothelialized rabbit thoracic aorta were examined in vitro. Aortas labelled with 35S in vivo, were exposed to each protease and the 35S-products released from the vessel were analysed. Aortas exposed to the same enzymes were examined by transmission electron microscopy of ruthenium red-stained sections, and the proteoglycan content evaluated by morphometric analysis. In uninjured vessels with endothelium intact, there was no evidence of release of proteoglycan by either enzyme unless very high concentrations were used. High concentrations of both plasmin and thrombin induced vacuolation of endothelial cells, and changes in the fine structure of smooth muscle cells. In contrast exposure of de-endothelialized vessels to smaller concentrations of plasmin or thrombin resulted in a significant loss of proteoglycan, and less marked changes in the morphology of the smooth muscle cells. Thrombin treatment released 35S-labelled products containing chondroitin-, dermatan- and heparan-sulphates whereas plasmin released products containing only chondroitin- and dermatan-sulphates together with other, unknown 35S-labelled products. These observations indicate the potential of non-specific, plasma-derived proteases to degrade arterial connective tissue.

Animals↗
PubMed1987

The identification of specific Rhesus-polypeptide-blood-group-ABH-active-glycoprotein complexes in the human red-cell membrane.

1. RhD,c and E immune complexes isolated from 3H- and 125I-surface-radiolabelled and unlabelled intact human red cells were analysed by SDS/polyacrylamide-gel electrophoresis. 2. Apparent Mr values of 31,900 for RhD polypeptide and 33,100 for Rhc,E polypeptide were obtained under both reducing and non-reducing conditions. Glycosylation of RhD,c and E polypeptides was not detected. 3. RhD,c and E immune complexes also contain a glycoprotein component. RhD glycoprotein (apparent Mr 45,000-100,000) is distinct from Rhc,E glycoprotein(s) (apparent Mr 35,000-65,000). Rh (Rhesus) glycoprotein carbohydrate moieties are susceptible to endo-beta-galactosidase digestion and carry blood-group-ABH determinants. This suggests the presence of polylactosaminoglycan-type structures. 4. Rh glycoproteins are not present in Rh immune complexes as a result of non-specific adsorption of membrane glycoproteins during the membrane-solubilization phase of immune-complex isolation because RhD immune complexes isolated from a 1:1 (v/v) mixture of Acde/cde and OcDE/cDE red cells do not contain blood-group-A-active glycoprotein. 5. Blood-group-A immune complexes isolated from group-A red cells of the appropriate Rh phenotypes contain the 31,900- and 33,100-apparent-Mr Rh polypeptides. 6. It was concluded from the above evidence that non-covalent Rh-glycoprotein-Rh-polypeptide complexes exist in the native red-cell membrane. 7. The 31,900- and 33,100-apparent-Mr Rh polypeptides are absent from blood-group-A immune complexes isolated from regulator type Rhnull cells (donor A.L.), but are replaced by a 33,800-apparent-Mr Rhnull-specific polypeptide (Rhnull polypeptide). It is suggested that Rhnull polypeptide is an aberrant product of the Rh gene complex.

Antigen-Antibody Complex↗
PubMed1987

Proteoglycan composition of rabbit arterial wall under conditions of experimentally induced atherosclerosis.

The concentration and composition of proteoglycans (PG) of the neointima developed following balloon catheter removal of aortic endothelium in rabbits, were assessed. PG were extracted from the aortic intimal-medial tissues with 4 M guanidinium chloride in the presence of protease inhibitors and purified subsequently by cesium chloride gradient ultracentrifugation and fractionation by high-performance liquid chromatography (HPLC). PG so obtained was analysed for its protein, cholesterol and glycosaminoglycan (GAG) content. For the characterization of the GAG moiety, an exhaustive proteolytic digestion was done. The GAG were then recovered by ethanolic precipitation and their relative distribution was determined after a selective enzymatic digestion using specific enzymes. Results show a significant increase in the amount of PG in the areas of the injured arterial wall covered by regenerated endothelium. In addition, changes in the composition of GAG were also found in the PG isolated from experimental animals when compared to PG isolated from normal aorta. A marked increase in the content of chondroitin sulfates and dermatan sulfate of injured tissue was seen. Hyaluronic acid content also changed in response to de-endothelialization and cholesterol feeding, but only moderately. The content of heparan sulfate remained unaffected in experimental tissues. Furthermore, cholesterol feeding aggravated the injury-induced increment of GAG. These findings are consistent with previously reported morphological observations, and correlate well with reports that arterial injury and cholesterol feeding act synergistically in the evolution of the atherosclerotic lesion and provide further evidence that the interaction of lipid and PG of the arterial wall may be of particular importance to our comprehension of the pathogenesis of atherosclerosis.

Animals↗
PubMed1987

Residual leukemia cannot be detected in very early remission peripheral blood stem cell collections in acute non-lymphoblastic leukemia.

We have used a combined cell culture and cytogenetic approach to study the level of residual leukemia during the very early remission (VER) phase of acute non-lymphoblastic leukemia. Clonogenic leukemic cells were induced to proliferate by phytohemagglutinin-stimulated leucocyte conditioned medium and identified by a leukemia-associated karyotype t(8;21) and a morphological marker (Auer rod). When leukemic blasts were cultured, the leukemic karyotype and Auer rods were most readily detected after 3-9 days. When VER blood cells were cultured, no leukemia-associated karyotype or Auer rods could be detected. Based on the number of VER blood cell derived metaphases analysed, the incidence of leukemic blasts among dividing cells is less than 2%.

Cells, Cultured↗
PubMed1987

CT body stereotaxic system for placement of needle arrays.

A new CT body stereotaxic system that is particularly suited to multiple placements of needles precisely in parallel is described. By scanning through a right triangle placed on the patient's skin, the stereotaxic method defines an entry point for the first needle placement. An articulating arm is then used to aim the needle at the entry point and hold the needle at the correct angle. The arm can be angled so that the complex approaches from one scan plane to another can be made to place needle arrays through inaccessible lesions, for instance, beneath the diaphragm. Animal and phantom studies have shown that placement of multiple needle arrays in parallel from CT scan data is possible.

Biopsy, Needle↗
PubMed1986

The effects of acute high dose fentanyl administration on experimental brain edema: analysis of intracranial pressure, systemic arterial pressure, central venous pressure and brain water content.

In rabbits who had brain edema and intracranial hypertension induced by a combined cold lesion (over the left hemisphere) and a metabolic blocker (6-aminonicotinamide), the authors analyzed the response of multiple parameters following the administration of 6 mcg/kg/dose of fentanyl every 5 minutes for 1 hour (12 doses), combined with nitrous oxide anesthesia. All animals were mechanically ventilated and the PaCO2 was maintained at 37-43 torr. Gross pathology and extent of Evans Blue extravasation was no different from pretreatment control animals. The systolic arterial pressure and the central venous pressure showed no change during the experiment. The intracranial pressure remained elevated despite fentanyl, but did not increase or decrease throughout the administration of the agent. The brain water content remained unchanged in the right hemisphere, but revealed a significant increase following fentanyl in the cold-lesioned left hemisphere for the gray (p less than 0.005) and white matter (p less than 0.05).

Animals↗
PubMed1986

An experimental study on the effects of DMSO and indomethacin on cerebral circulation and intracranial pressure.

Albino rabbits with a cryogenic lesion to the left parieto-occipital cortex had cerebral blood flow studies (CBF) with the hydrogen clearance technique 24 hours after the insult. Similar subgroups were treated with DMSO (1 g/kg) bolus, DMSO (2 g/kg) infusion, indomethacin (20 mg/kg) bolus, and indomethacin followed by DMSO. Following DMSO bolus administration there was an immediate rise in CBF over both hemispheres, with a significant paradoxical decrease at 30 minutes, followed by a second smaller rise at 60 minutes. With DMSO infusion, the rise in CBF was sustained throughout the infusion period with no paradoxical decrease. With indomethacin there was an initial decrease immediately following the drug, and at 60 minutes there was a rise in the insulted left hemisphere, more than the right one. Indomethacin administration 15 minutes prior to DMSO failed to halt the immediate increase in CBF noted following DMSO bolus injection. These results, together with the changes that occurred in intracranial pressure and brain water content, are analyzed.

Animals↗
PubMed1986

Carrier-linked primaquine in the chemotherapy of malaria.

The antimalarial effect of intravenously administered primaquine (PQ) can be improved and its toxicity diminished by linking it to a macromolecular carrier protein. A thiol-containing primaquine derivative 8-[[4-(2-amino-3-mercaptopropionamido)-1-methylbutyl]amino]-6- methoxyquinoline was synthesized. This compound could readily be linked via a disulfide bond to a carrier protein containing (pyridyldithio)propionate groups. The derivative was coupled to serum albumin as well as to serum albumin that contained covalently linked lactose residues. The protein-drug conjugates were tested for their antimalarial activity in mice inoculated with Plasmodium berghei. The causal prophylactic activity of the conjugate with the lactosaminated serum albumin was 2 times higher than that of the free drug; the mean causal prophylactic doses (CPD50) were 6 and 13 mg of primaquine base/kg, respectively. Moreover, its acute lethal toxicity had decreased at least 6.5-fold (mean lethal dose (LD50) greater than 85 mg of primaquine base/kg). The therapeutic index of this conjugate was at least 12 times higher than that of the free drug. This allowed the administration of a dose that cured 100% of the animals (17.5 mg of primaquine base/kg), in a single injection. With unmodified serum albumin the conjugate showed an increased therapeutic efficacy (the CPD50 was approximately 10 mg of primaquine base/kg) and a strongly reduced lethal toxicity.

Animals↗
PubMed1986

Mural thrombi of the right atrium and acute bacterial endocarditis complicating a LeVeen shunt.

A cirrhotic woman with a LeVeen shunt developed right atrial thrombi, acute bacterial endocarditis, and a major pulmonary embolus. The right atrial mural thrombi and resultant pulmonary emboli arose as a result of the placement of the venous end of the LeVeen shunt within the right atrium. This untoward event must be added to the growing list of complications associated with the placement of such catheters.

Adult↗
PubMed1986

Acute experimental cerebral ischemia: MR enhancement using Gd-DTPA.

The effects of a paramagnetic contrast agent, gadolinium-DTPA (Gd-DTPA), on magnetic resonance (MR) imaging of acute cerebral ischemia was investigated in a feline model of middle cerebral artery occlusion. Imaging was performed both before and after administration of an intravenous dose of 0.2 mmol/kg of Gd-DTPA. The animals were then sacrificed for pathologic correlation. No changes in intensity or relaxation times were noted before or after Gd-DTPA administration in two animals with 2 hours of occlusion. Infarcts were noted before and after contrast enhancement in all six cats with ischemia of greater than 16-hours duration. Gd-DTPA caused significant increase in intensity of infarct but not in that of normal cerebral tissue. Rapid enhancement was visible in infarcts of 16-24 hours, but such enhancement was slower in infarcts of 72-168 hours, presumably owing to slowed inflow caused by increased vasogenic edema in the latter group. Contrast enhancement of acute cerebral ischemic lesions with Gd-DTPA offers no improvement in sensitivity of MR imaging, although the conspicuity of the lesion may be improved. Additionally, contrast media may provide potential temporal and pathophysiological data for better characterization of cerebral ischemia.

Animals↗
PubMed1986

CT body stereotaxis: an aid for CT-guided biopsies.

A new body stereotaxic system used to facilitate CT-guided biopsies is described. By scanning through a triangle placed on the patient's skin, the method defines an entry point for the biopsy. An articulating arm is then used to aim the needle at the entry point and hold the needle at the correct angle. The arm can be angled so that complex approaches from one scan plane to another can be made in order to take biopsies of lesions beneath the diaphragm. Using the system, 23 of 25 lesions were hit on the first needle manipulation; two manipulations were needed for each of the other two lesions. In comparison with previous experience, procedure time was decreased and the numbers of needle manipulations and localization scans were decreased 75% and 90%, respectively.

Biopsy, Needle↗
PubMed1985

Seat belts.

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Adult↗