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B Allan

Publications and source records attributed to B Allan.

10 recordsLinked to original sources

AIDS help-line.

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Acquired Immunodeficiency Syndrome

Paediatric AIDS.

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Acquired Immunodeficiency Syndrome

Hypertension registers in general practice: levels of control and nondrug management.

Sixty-five general practitioners throughout Northland agreed to establish and maintain hypertension registers for a three year trial period beginning in 1982. Opportunistic blood pressure screening was undertaken of all patients aged 20-69 attending practices for whatever reason. Patients with an average of six readings on at least three separate occasions which exceeded WHO criteria for hypertension (diastolic blood pressure greater than 95 mmHg and/or systolic blood pressure greater than 160 mmHg) were entered onto the registers as were patients already receiving antihypertensive drugs. In all 3703 patients were registered. The percentage exceeding WHO criteria fell from 49.4% to 38.8% for those followed up for twelve months and from 48.6% to 34.5% for those followed up for twenty-four months. The percentage with diastolic blood pressure less than 90 mmHg increased significantly for each follow up group and with length of follow up. Overall 8.2% at entry were managed without drugs, for those followed up for thirty months this fell to 6.2% with individual practice percentage varying from nil to over twenty. There appears scope to manage between 10-20% of hypertensives without drugs.

Adult

Autonomic regulation of potassium release from human labial salivary glands in vitro.

Labial salivary-gland slices from normal human subjects were incubated in vitro according to various protocols. The autonomic regulation of these was significantly different from that of most major salivary glands. K release was stimulated by incubation with a cholinergic agonist but not with alpha- or beta-adrenergic agonists. The cholinergically-induced K release was dependent on agonist concentration and was inhibited by the addition of atropine, and by the removal of Ca in the presence of EGTA.

Adult

The role of prophylactic brain irradiation in limited stage small cell lung cancer: clinical, neuropsychologic, and CT sequelae.

Ninety-four patients with limited stage small cell lung cancer treated between 1981 and 1985 with a regimen including prophylactic brain irradiation (PBI) after combination chemotherapy were assessed for compliance with PBI, brain relapse, and neurologic morbidity. Seventy-seven percent of patients had PBI and of these, 22% developed brain metastases after a median time of 11 months post treatment. The brain was the apparent unique initial site of relapse in 10% of PBI cases but more commonly brain relapse was preceded or accompanied by failure at other sites, especially the chest. Brain metastases were the greatest cause of morbidity in 50% of PBI failures. Twelve of 14 PBI patients alive 2 years after treatment had oncologic, neurologic, and neuropsychological evaluation, and brain CT. All long-term survivors were capable of self care and none fulfilled diagnostic criteria for dementia, with three borderline cases. One third had pretreatment neurologic dysfunction and two thirds post treatment neurologic symptoms, most commonly recent memory loss. Fifty percent had subtle motor findings. Intellectual functioning was at the 38th percentile with most patients having an unskilled occupational history. Neuropsychologic impairment ratings were borderline in three cases and definitely impaired in seven cases. CT scans showed brain atrophy in all cases with mild progression in those having a pre-treatment baseline. Periventricular and subcortical low density lesions identical to the CT appearance of subcortical arteriosclerotic encephalopathy were seen in 82% of posttreatment CT studies, and lacunar infarcts in 54%. Neuropsychologic impairment scores and the extent of CT periventricular low density lesions were strongly associated (rank correlation 0.7, p less than .05). Overall, PBI after intensive combination chemotherapy did not induce gross dementia or neurologic dysfunction but its risk/benefit ratio is not overwhelmingly favorable, with failure to prevent brain relapse in 1/5 patients and subtle but detectable motor findings and neuropsychologic impairment in the majority.

Atrophy

Heat shock response of Pseudomonas aeruginosa.

The general properties of the heat shock response in Pseudomonas aeruginosa were characterized. The transfer of cells from 30 to 45 degrees C repressed the synthesis of many cellular proteins and led to the enhanced production of 17 proteins. With antibodies raised against the Escherichia coli proteins, two polypeptides of P. aeruginosa with apparent molecular weights of 76,000 and 61,000 (76K and 61K proteins) were shown to be analogous to the DnaK and GroEL heat shock proteins of E. coli due to their immunologic cross-reactivity. The major sigma factor (sigma 87) of P. aeruginosa was shown to be a heat shock protein that was immunologically related to the sigma 70 of E. coli by using polyclonal antisera. A hybridoma was produced, and the monoclonal antibody MP-S-1 was specific for the sigma 87 and did not cross-react with sigma 70 of E. coli. A smaller 40K protein was immunoprecipitated with RNA polymerase antisera from cells that had been heat shocked. The 40K protein was also associated with RNA polymerase which had been purified from heat-shocked cells and may be the heat shock sigma factor of P. aeruginosa. Exposure to ethanol resulted in the production of seven new proteins, three of which appeared to be heat shock proteins.

Animals

DNA-dependent RNA polymerase from Pseudomonas aeruginosa.

DNA-dependent RNA polymerase was purified from Pseudomonas aeruginosa. The subunit structure was typical of other eubacterial RNA polymerases in having beta' (157,000), beta (148,000), sigma (87,000), and alpha 2 (45,000) subunits as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme was dependent on Mg2+, displaying optimal activity at 10 mM MgCl2. Ca2+ and Zn2+ could not replace MgCl2 in the assay system, while Mn2+, produced partial activity. KCl at concentrations greater than 10 mM inhibited enzyme activity. Optimal enzyme activity was observed at pH 8.5-9.0. The RNA polymerase was stable in 50% (w/v) glycerol at 4 degrees C for more than 3 months. Enzyme activity was inhibited in vitro by heparin, streptolydigin, streptovaracin, actinomycin D, and rifampicin.

DNA-Directed RNA Polymerases