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D Graham

Publications and source records attributed to D Graham.

At least 109 records · Page 6Linked to original sources

Chlamydial antibody crossreactivity with peripheral blood mononuclear cells of patients with ankylosing spondylitis: the role of HLA B27.

We have previously reported the association of Chlamydia trachomatis with HLA B27+ related diseases. To investigate the possibility that chlamydial antibodies serve to localize the immune response in such diseases, we examined the crossreactivity of chlamydial antibodies (rabbit anti-D and anti-L2 serotypes) with peripheral blood mononuclear cells of patients with ankylosing spondylitis (AS) and anterior uveitis (AU) and with human and bovine ocular tissue and cells in culture. Our results indicate a significantly increased percentage binding of chlamydial antibody (D serotype) to the mononuclear cells of HLA B27+ patients with AS when compared with HLA B27- patients with AS (12.9% +/- 2.2 versus 5.4% +/- 2.2), B27+ controls (5.5% +/- 1.5) and B27- controls (6.1% +/- 1.0). There was no significant difference between controls and HLA B27+ patients with AU (6.6% +/- 1.9) and B27- patients with AU (8.7% +/- 1.1). This crossreactivity could not be blocked by monoclonal HLA B27 antibody. Chlamydial antibodies (D and L2) crossreact with human and bovine conjunctiva but not uvea, tissue culture derived iris fibroblasts or smooth muscle cells. Our results provide additional support for the concept of crossreactivity between antibodies to microbial agents and peripheral blood mononuclear cells of patients with HLA B27+ AS.

Adolescent

Characterization of [3H]paroxetine binding to rat cortical membranes.

Paroxetine is a selective and potent inhibitor of 5-hydroxytryptamine uptake into serotonergic neurons. The specific binding of [3H]paroxetine to rat cortical membranes at 22 degrees C was examined in this study. Our results indicate the presence of a single saturable high affinity binding component for [3H]paroxetine. Scatchard analysis revealed a Kd of 0.15 +/- 0.01 nM, and a Bmax of 549 +/- 36 fmol/mg protein. The kinetically derived dissociation constant was 0.034 +/- 0.008 nM. [3H]Paroxetine binding was inhibited selectively by 5-HT uptake blockers, and a good correlation was demonstrated between the potency of various drugs to inhibit [3H]paroxetine binding and [3H]5-hydroxytryptamine uptake. Also, lesions performed with the neurotoxin, 5,7-dihydroxytryptamine resulted in a 94% decrease in endogenous 5-hydroxytryptamine levels and concomitantly, a 90% reduction in [3H]paroxetine binding when compared to sham controls. These results indicate that the binding site labelled by [3H]paroxetine is associated with the neuronal 5-hydroxytryptamine transporter complex.

Animals

Purification and characterization of the glycine receptor of pig spinal cord.

A large-scale purification procedure was developed to isolate the glycine receptor of pig spinal cord by affinity chromatography on aminostrychnine agarose. After an overall purification of about 10 000-fold, the glycine receptor preparations contained three major polypeptides of Mr 48 000, 58 000, and 93 000. Photoaffinity labeling with [3H]strychnine showed that the [3H]strychnine binding site is associated with the Mr 48 000 and, to a much lesser extent, the Mr 58 000 polypeptides. [3H]Strychnine binding to the purified receptor exhibited a dissociation constant KD of 13.8 nM and was inhibited by the agonists glycine, taurine, and beta-alanine. Gel filtration and sucrose gradient centrifugation gave a Stokes radius of 7.1 nm and an apparent sedimentation coefficient of 9.6 S. Peptide mapping of the [3H]strychnine-labeled Mr 48 000 polypeptides of purified pig and rat glycine receptor preparations showed that the strychnine binding region of this receptor subunit is highly conserved between these species. Also, three out of six monoclonal antibodies against the glycine receptor of rat spinal cord significantly cross-reacted with their corresponding polypeptides of the pig glycine receptor. These results show that the glycine receptor of pig spinal cord is very similar to the well-characterized rat receptor protein and can be purified in quantities sufficient for protein chemical analysis.

Animals

Cholera.

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Cholera

Variable distributions of serum creatine kinase reference values. Relationship to exercise activity.

Although the effect of exercise on serum creatine kinase (CK: EC 2.7.3.2) activity is well known, no standard protocol for blood collection conditions has been developed. Variable frequency distributions of CK activities have been reported for reference range samples from different laboratories and have been attributed to laboratory differences. In this study the frequency distributions of creatine kinase activities (CK: EC 2.7.3.2) in serum samples obtained from the same groups of volunteers varied from a normal Gaussian distribution, to skewed distributions, on different occasions. In one collection extremely high CK values followed the performance of an eccentric exercise step test 5-8 days previously. In 2 students serum CK activities had not returned to resting values 12 and 15 days later. Peak serum CK values occurred within 24 h of other types of exercise. Serum CK frequency distributions in blood samples obtained from a group of nurses was skewed, whereas the distribution in mothers of school children was Gaussian. When repeat samples were obtained from the nurses after instruction to avoid exercise, the distribution became Gaussian. In view of the increasing levels of physical activity in the community, a standard protocol for serum CK analysis is required, in which exercise activity over the previous three weeks should be documented. Test subjects should be counselled to avoid unusual eccentric exercise and sampling should include 3 tests at least 1 week apart.

Adolescent

Microbiology of chronic otitis media with effusion among Australian Aboriginal children: role of Chlamydia trachomatis.

Serum, eye secretions, post-nasal swabs, external ear swabs and middle ear effusions (MEE) were collected from 131 Australian Aboriginal children with chronic otitis media with effusion (COME). The children were all resident in a trachoma endemic region. Chlamydia trachomatis was recovered from the MEE of 2 children. Probable bacterial pathogens were isolated from 34 (12.7%) ears. The remainder were sterile (52.4%) or contained normal skin flora (34.9%). Serum and secretions were examined by the microimmunofluorescent technique for the presence, titre and serotype of anti-chlamydial antibody. Antibody, predominantly of the C serotype, was found in a high percentage of sera (80%) and secretions (approximately 50%). This serotype is associated with ocular trachoma. It is concluded that C. trachomatis is associated with COME among some Aboriginal children in this trachoma endemic area.

Adolescent

Decreased chemiluminescent associated phagocytic response of peripheral blood mononuclear cells to Chlamydia trachomatis in patients with HLA-B27+ anterior uveitis.

The chemiluminescent (CL) associated phagocytic response of peripheral blood monocytes to two serovars of Chlamydia trachomatis, Shigella flexneri and zymosan was assessed in a group of 26 patients with anterior uveitis (AU). HLA-B27+ patients with AU, when compared to HLA-B27- patients with AU and appropriate controls, had a significantly decreased CL response to C. trachomatis but no difference between groups in the response to S. flexneri and zymosan. The decreased chemiluminescent (phagocytic) response of mononuclear phagocytes to Chlamydiae may indicate an important abnormality in the pathogenesis of HLA-B27+ AU.

Adolescent

The use of intravenous meptazinol for analgesia in colonoscopy.

A double blind study comparing intravenous pethidine and meptazinol has been performed to establish the efficacy and safety of meptazinol as an analgesic agent in colonoscopy. Twenty two patients received pethidine and 23 patients received meptazinol and no difference in analgesic effect or sedative effect could be demonstrated either by observer or patient assessment using a visual analogue scale. A group of 10 patients in the pethidine group and 9 in the meptazinol group had continuous recording of electrocardiogram, pulse rate and blood pressure throughout the procedure. Significant falls in both systolic and diastolic blood pressure were recorded in the pethidine group but not the meptazinol group. Benign cardiac arrhythmias were recorded in both groups before and after the administration of premedicant drug and 1 patient in each group had transient ST depression. Side effects were recorded with equal frequency in each group except for vomiting which occurred in 5 of 23 meptazinol patients but none of the pethidine patients. Meptazinol is an effective analgesic drug in colonoscopy which produces less cardiovascular depression than pethidine and thus may be useful in selected patients especially the elderly or those with known cardiovascular disease.

Azepines

Chemical properties, distribution, and physiology of plant and algal carbonic anhydrases.

Plant carbonic anhydrases (CAs) have a range of molecular weights (MW). Among flowering plants, dicotyledons with C3 photosynthesis have two isoenzymes of 140-250K each with 6 subunits, while monocotyledons have two isoenzymes of 42-45K. Plant and animal CAs have a similar amino acid content, subunit size and zinc content, suggesting they are homologous proteins, although the higher plant CAs have no esterase activity and are not strongly inhibited by sulfonamides. Algal CAs vary widely in MW and some are highly sensitive to sulfonamides like the animal enzymes. The two plant isoenzymes, from the chloroplast and cytosol, can be separated by gradient polyacrylamide gel electrophoresis and subsequently visualized by enzymic H+ ion production. In plants, CAs probably facilitate diffusion of CO2 to the site of photosynthetic fixation; they may also have a role in pH regulation, in the use of bicarbonate by aquatic plants and in concentrating inorganic carbon within the chloroplast.

Carbonic Anhydrases

Photoaffinity-labelling of the glycine receptor of rat spinal cord.

The irreversible incorporation upon ultraviolet illumination of the glycine receptor antagonist, [3H]strychnine, into synaptic membrane fractions of rat spinal cord has been investigated. The specificity of this photoaffinity-labelling reaction for the glycine receptor was demonstrated by the following results: (a) the Kd value (9.7 nM) of the glycine-displaceable irreversible incorporation of [3H]strychnine was similar to the previously reported Kd of [3H]strychnine binding to the glycine receptor; (b) pre-illumination of the membranes with unlabelled strychnine led to a corresponding reduction in the number, but not the affinity, of reversible glycine-displaceable [3H]strychnine binding sites; (c) the ultraviolet light-induced incorporation into the membranes of [3H]strychnine was inhibited by different glycine receptor agonists; other neurotransmitter substances had little or no effect. Also, [3H]strychnine alone was shown to be stable upon illumination with ultraviolet light; this suggests that photocrosslinking of [3H]strychnine may require energy transfer from specific groups of its high-affinity receptor binding site. Upon sodium dodecyl sulphate/polyacrylamide gel electrophoresis a single labelled polypeptide with a relative molecular mass of 48000 was revealed from spinal cord membranes photoaffinity-labelled with [3H]strychnine. Spinal cord membranes photoaffinity-labelled with the gamma-aminobutyric acid receptor ligand [3H]flunitrazepam, however, gave a single polypeptide with a relative molecular mass of 5- 0000. Treatment of membranes, labelled with [3H]strychnine, by endoglycosidase H did not alter the relative molecular mass of the 48000-Mr labelled polypeptide. Trypsin treatment, on the other hand, successively produced major fragments of relative molecular masses of 42000 and 37000. Also, even after extensive treatment with trypsin or chymotrypsin, greater than or equal to 90% of the radioactivity incorporated into the labelled membranes remained membrane-associated. It is concluded that the strychnine binding site of the glycine receptor is located on a protease-inaccessible, i.e. probably hydrophobic domain of the 48000-Mr subunit.

Affinity Labels

The natural disease course of ankylosing spondylitis.

One hundred fifty war veterans with ankylosing spondylitis were entered into a prospective study in 1947. In 1957, 142 were traced, and they have been reviewed periodically. Eighty-one of these patients were still alive in 1980. Information was obtained from 67 (83%) of the survivors and 51 were reexamined. This report is based on the clinical findings in these 51 patients, who have a mean disease duration of 38 years. Forty-seven (92%) were functioning well. The disease in 21 (41%) had progressed to cause severe spinal restriction. Of those, 12 had peripheral joint involvement early in their course and 9 had iritis. Seventy-four percent of the patients who had mild spinal restriction after 10 years did not progress to having more severe restriction. Eighty-one percent of the patients who had severe spinal restriction in 1980 were severely restricted within the first 10 years. Hips that were normal after 10 years of disease did not become diseased subsequently. This study suggests that a predictable pattern of ankylosing spondylitis emerges within the first 10 years of the disease.

Adult