Biomedical subjects
Publications and source records attributed to M C Murray.
The first potent small molecule sst2 antagonists are reported. Altering known sst2 agonist molecules yielded compounds with high sst2 binding affinity and full antagonist activity. Compound 7a, for example, displaced somatostatin binding to the sst2 receptor with an IC(50)=2.9 nM and antagonized somatostatin action with an IC(50)=29nM.
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The objective of this study was to determine whether the maternal infecting human immunodeficiency virus (HIV) type 1 clade affects mother-to-child transmission frequency. Mothers in the mother-to-child HIV-1 transmission study in Nairobi, Kenya, were grouped by HIV-1 status of their first enrolled child: uninfected, perinatally infected, or postnatally infected. Restriction fragment length polymorphism (RFLP) analysis was used to determine HIV-1 viral clades of nested polymerase chain reaction products from HIV-1 protease or p24 genes. When inconclusive, sequencing determined the clade. Clade distributions within the groups were compared. The 3 groups displayed a uniform clade distribution. The predominant clades were A (59%) and D (20%). Clades B, C, F, mixed, and recombinant infections comprised the remainder (21%). No significant association was seen between clades A and D and either frequency or mode of vertical transmission. RFLP analysis revealed 2 clade B infections, 9 mixed, and 5 p24/protease recombinant infections in the study population.
Most of the information available to guide the clinician in making occlusal records focuses on the clinical techniques and methods involved. There is little objective information regarding the use of the more recently introduced elastomeric materials which are growing in popularity in the clinic. Much of the published work relies on the clinical experience of the authors rather than the properties of the material to be used to make the occlusal records. This paper aims to review the materials currently available to clinicians for use in occlusal registrations. The materials are discussed with regard to their suitability for the task and suggestions given regarding their use. Setting aside considerations of technique, it is suggested that there would be value in basing the selection of materials for occlusal registration on objective research. However, it may well be that the technique, as with many other things in dentistry, is as important as the specific properties of the materials used.
OBJECTIVE: To test the efficacy of a group-administered cognitive-behavioral psychotherapy (CBT) protocol for pediatric posttraumatic stress disorder (PTSD) after a single-incident stressor. METHOD: After a school-wide selection-to-treatment procedure conducted in two elementary and two junior high schools, children and adolescents with DSM-IV PTSD by structured interview were entered into an 18-week, group-administered CBT protocol using a single case across time and setting experimental design. Assessments of PTSD, anxiety, depression, trait anger, locus of control, and disruptive behavior were conducted at baseline, posttreatment, and at 6-month follow-up. RESULTS: Experimental control across time (staggered start date) and setting (school and age) was demonstrated. Fourteen of 17 subjects completed treatment. Of these, 8 (57%) no longer met DSM-IV criteria for PTSD immediately after treatment; 12 (86%) of 14 were free of PTSD at 6-month follow-up. On intent-to-treat analyses, treatment produced a robust beneficial effect posttreatment on the Clinician-Administered PTSD Scale-Child and Adolescent Version, with additional improvement accruing at follow-up (p < .001). Improvements of a similar magnitude were seen for depression (p < .001), anxiety (p < .001), and anger (p < .005). Locus of control remained external from pre- to posttreatment but became strongly internal at follow-up (p < .001). CONCLUSION: More clinical trials are required to confirm that CBT is a safe, acceptable, and effective treatment for PTSD in children and adolescents.
The results of a study to investigate the effectiveness of a propolis-containing mouthrinse in the inhibition of de novo plaque formation are presented. Subjects used a propolis-containing rinse, a negative control and a positive control in a double-blind, parallel, de novo plaque formation study design. The chlorhexidine mouthrinse was significantly better than the others in plaque inhibition. The propolis-containing rinse was marginally better than the negative control, but this difference was not significant.
OBJECTIVES: To compare the relative amounts of elastase (primary polymorphonuclear leucocyte granule constituent) and lactoferrin (secondary PMN granule constituent) in the gingival crevicular fluid (GCF) of healthy, gingivitis and periodontitis sites. DESIGN: This cross-sectional study looked at the two GCF constituents in three categories of disease status within the same subject. MATERIALS AND METHODS: Patients with chronic adult periodontitis were screened and those exhibiting all three types of sites ie periodontally healthy, gingivitis and periodontitis sites were recruited (n=10) and had GCF collected from the three sites. Lactoferrin and elastase were measured in eluates of GCF by enzyme-linked immunosorbent assay. RESULTS: The absolute amount of lactoferrin measured in ng per 30 s samples was significantly lower in healthy and gingivitis sites as compared to periodontitis sites; however this difference failed to reach significance when the concentration of lactoferrin in GCF was used as the analytical unit. No significant differences were found for elastase levels at any sites when expressed as either absolute amounts or concentrations. Secondary granule release, as evidenced by lactoferrin levels, occurs during cell migration and the process is independent of primary granule release, which is thought to correlate with PMN activation. The relationship between granule constituents in the samples showed significant differences, the highest lactoferrin/elastase ratio being at periodontitis sites (P<0.001). CONCLUSIONS: These findings imply a change in the relative amounts of elastase and lactoferrin released at different disease level sites, wth an almost 10-fold increase in the proportion of lactoferrin to elastase in periodontitis sites over healthy and gingivitis sites. This variation in the release by PMNs of primary and secondary granule constituents may indicate alterations in PMN function in different disease environments.
Rhoptries have been isolated from Plasmodium falciparum schizont-infected erythrocytes by isopycnic density centrifugation. Gradient fractions were analyzed by immunoblotting with antibodies against two polypeptides of 140 and 110 kDa, known to be components of the rhoptry. The proteins were present primarily in fractions with a density of 1.16 g ml-1. Electron microscopy of these fractions indicated they were enriched in rhoptries. For the most part, the isolated organelle retained in situ morphology, although some rhoptries were distorted, indicating the structure of some of the organelles is not rigid. Electrophoretic analysis of the rhoptry fractions indicated the presence of a number of proteins, many of which have not been identified to date. Properties of proteins in the isolated rhoptry were examined using the 140 and 110 kDa proteins as representative markers. Both proteins are present in a complex with a 130-kDa protein, as all three co-immunoprecipitate. At the late schizont stage, the rhoptry proteins are present in two distinct forms; a soluble form with an Mr of 480 000 which would correspond to a single copy of the 140/130/110 kDa complex and a form that can be sedimented at 130 000 x g. Properties of the sedimentable form suggest that the proteins are included in structures that resemble membranes. Ionic detergents were required to solubilize the proteins while high concentrations of NaCl and Na2CO3 resulted in only partial solubilization. Furthermore, treatment of disrupted rhoptries with phospholipase A and C resulted in the release of proteins into the soluble form.
Phosphorylation changes in the erythrocyte membrane and cytoskeletal proteins as a consequence of infection by the malarial parasite Plasmodium falciparum were examined. Spectrin, band 3, band 4.1, ankyrin and glycophorin are phosphorylated in normal erythrocytes. As a consequence of invasion by the merozoite, the extracellular stage of the parasite, into 32P-prelabeled normal erythrocytes, all the major 32P-labeled erythrocyte proteins are dephosphorylated. As the parasite develops intracellularly from the immature ring stage to the mature schizont stage, selective phosphorylation of certain host proteins, spectrin, ankyrin and band 3 is observed. Band 4.1 does not appear to incorporate [32P]phosphate at any stage of parasite development. These observed phosphorylation changes may be important in the regulation of the cytoskeletal organization in P. falciparum-infected cells.
The sialic acid residues of alpha 1-acid glycoprotein and fetuin were modified by introduction of an amino residue, such as glycine and [3H]glycine. This modification involved (a) the selective periodate oxidation of the exocyclic carbon atoms of the sialic acid residue generating an aldehyde group at C-7, and (b) the reduction of the Schiff base formed with an amino compound by use of sodium cyanoborohydride. Thin layer chromatography, high pressure liquid chromatography, and amino acid composition data of the modified glycoprotein showed that the conversion was essentially quantitative. The glycine-modified sialic acids were isolated by mild acid hydrolysis and identified by g.l.c.-m.s. and n.m.r. spectroscopy, thus confirming that the quantitative modification produced a glycine-aminated C-7 sialic acid analog. Strong acid hydrolysis of the glycine-modified sialic acid yielded a fragment that had chromatographic characteristics similar to those of glycine.
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The residues of DDT and its analogs were estimated in a number of cod liver samples (Gadus morhua) collected at six sampling sites off the Atlantic Coast of the Maritime Provinces of Canada during the summer of 1971. The residue levels indicated widespread distribution of DDT over the entire region sampled. Variations in the relative contributions of p,p'-DDE and p,p'-DDT to the total DDT residues (xiDDT) were noted and the tendency for these residues to preferentially accumulate in lipid rich tissues was demonstrated. The residue levels found in cod livers were compared to the residue levels determined in cod flesh taken from some of the same specimens and also to residue levels in commercially refined cod liver oils. Samples of each of these types were stored at -29 degrees C and analyzed in 1973 for DDT and PCB simultaneously. The xiDDT residues determined by both methods of analysis were compared.
Tooth wear leads to alterations in both static and functional occlusal contacts and may contribute to temporomandibular joint disorders and dysfunction. Treatment of tooth wear may be time consuming, expensive and destructive of remaining tooth tissues. Bruxism has been associated with the recording of abnormally high clenching forces. This paper describes a technique for the provision of the canine riser restoration, which deliberately alters the cuspal incline in canine teeth to provide a canine guided occlusion. These restorations may help to control excessive loading of teeth, limit further tooth wear and assist in the management of temporomandibular disorders and dysfunction.