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P Brown

Publications and source records attributed to P Brown.

At least 19 recordsLinked to original sources
PubMed1992

Community clinics for leg ulcers and impact on healing.

OBJECTIVE: To evaluate the effectiveness of community clinics for leg ulcers. DESIGN: All patients with leg ulceration were invited to community clinics that offered treatment developed in a hospital research clinic. Patients without serious arterial disease (Doppler ankle/brachial index > 0.8) were treated with a high compression bandage of four layers. SETTING: Six community clinics held in health centres in Riverside District Health Authority supported by the Charing Cross vascular surgical service. PATIENTS: All patients referred to the community services with leg ulceration, irrespective of cause and duration of ulceration. MAIN OUTCOME MEASURES: Time to complete healing by the life table method. RESULTS: 550 ulcerated legs were seen in 475 patients of mean (SD) age 73.8 (11.9) years. There were 477 venous ulcers of median size 4.2 cm2 (range 0.1-117 cm2), 128 being larger than 10 cm2. These ulcers had been present for a median of three months (range one week to 63 years) with 150 present for over one year. Four layer bandaging in the community clinics achieved complete healing in 318 (69%) venous ulcers by 12 weeks and 375 (83%) by 24 weeks. There were 56 patients with an ankle/brachial arterial pressure index < 0.8, indicating arterial disease. The 50 patients with pressure index < 0.8 > 0.5 were treated with reduced compression, and 24 (56%) healed by 12 weeks and 31 (75%) by 24 weeks. The figures for overall healing for all leg ulcers were 351/550 (67%) at 12 weeks and 417/550 (81%) at 24 weeks, compared with only 11/51 (22%) at 12 weeks before the community clinics were set up. CONCLUSIONS: Community clinics for venous ulcers offer an effective means of achieving healing in most patients with leg ulcers.

Aged↗
PubMed1992

Familial Creutzfeldt-Jakob disease (codon 200 mutation) with supranuclear palsy.

OBJECTIVE: To identify a possible gene defect in a large kindred with atypical Creutzfeldt-Jakob disease (CJD). SUBJECTS: Over 360 kindred members, with and without progressive dementia. METHODS: Family, hospital, and clinic records were reviewed. The DNA was extracted from paraffin-embedded brain tissue of two deceased patients, and from blood leukocytes of nine healthy persons at risk. DNA was subjected to polymerase chain reaction and then analyzed by restriction endonuclease and single nucleotide primer extension. RESULTS: Nine family members had progressive fatal neurological disease consistent with CJD without myoclonus or typical electroencephalographic findings. Supranuclear gaze palsy was present in all five patients who underwent eye examinations. Two neuropathologically confirmed cases and five of nine at-risk family members had an identical mutation (GAG to AAG, glutamic acid to lysine) in codon 200 of the amyloid gene (PRNP) on chromosome 20. CONCLUSIONS: Clinically atypical CJD with early supranuclear gaze palsy but without myoclonus or characteristic electroencephalographic periodicity patterns is associated with the codon 200Lys mutation in the largest CJD kindred yet reported. The clinical concept of familial CJD should be enlarged to include this unusual phenotype.

Adult↗
PubMed1992

Fatal familial insomnia and familial Creutzfeldt-Jakob disease: disease phenotype determined by a DNA polymorphism.

Fatal familial insomnia (FFI) and a subtype of familial Creutzfeldt-Jakob disease (CJD), two clinically and pathologically distinct diseases, are linked to the same mutation at codon 178 (Asn178) of the prion protein gene. The possibility that a second genetic component modified the phenotypic expression of the Asn178 mutation was investigated. FFI and the familial CJD subtype segregated with different genotypes determined by the Asn178 mutation and the methionine-valine polymorphism at codon 129. The Met129, Asn178 allele segregated with FFI in all 15 affected members of five kindreds whereas the Val129, Asn178 allele segregated with the familial CJD subtype in all 15 affected members of six kindreds. Thus, two distinct disease phenotypes linked to a single pathogenic mutation can be determined by a common polymorphism.

Adult↗
PubMed1992

Recent human evolution in East Asia and Australasia.

In both East Asia and Australasia arguments for evolutionary continuity between middle-late Pleistocene hominid populations and modern Homo sapiens are of long standing. In both regions, however, problems of chronological distribution, dating and preservation of hominid skeletal materials provide an effective barrier to extending regional sequences back to 'archaic' Homo sapiens or Homo erectus. The earliest securely dated modern Homo sapiens in East Asia are currently represented by Zhoukoudian Upper Cave at a minimum of 29 ka BP. In Australia skeletal remains of modern Homo sapiens have been dated to 26 ka BP, with archaeological materials at 38 to 50 ka BP. Late Pleistocene human skeletons from sites like Coobool Creek are morphologically and metrically outside the range of recent Australian Aboriginal populations. Similarly Liujiang and the Upper Cave crania can be distinguished from recent East Asian 'Mongoloids'. Evolutionary change within the Holocene needs to be taken into consideration when the evidence for regional evolutionary continuity is considered.

Animals↗
PubMed1992

Creutzfeldt-Jakob disease cosegregates with the codon 178Asn PRNP mutation in families of European origin.

We recently discovered an amino acid-altering heterozygous mutation in codon 178 of the PRNP amyloid precursor gene in patients with familial Creutzfeldt-Jakob disease. This mutation is now shown to be associated with the occurrence of disease in 7 unrelated families of Western European origin, among which a total of 65 members are known to have died from Creutzfeldt-Jakob disease. The mutation was detected in each of 17 tested patients, including at least 1 affected member of each family, and in 16 of 36 of their first-degree relatives, but not in affected families with other mutations, patients with the nonfamilial form of the disease, or 83 healthy control individuals. Linkage analysis in two informative families yielded a lod score of 5.30, which, because no recombinants were found, strongly suggests that codon 178Asn is the actual disease mutation.

Adult↗
PubMed1992

Phenotypic characteristics of familial Creutzfeldt-Jakob disease associated with the codon 178Asn PRNP mutation.

A group of 43 patients from seven families affected by Creutzfeldt-Jakob disease (CJD) with the codon 178Asn mutation of the PRNP amyloid precursor gene is compared to a group of 211 patients with the sporadic form of the disease. As a group, the patients with the codon 178Asn mutation had an earlier age at onset of illness (almost always presenting as an insidious loss of memory), a longer duration of illness, and an absence of periodic electroencephalographic activity. Transmission of disease to primates was accomplished using brain tissue homogenates from 6 of 10 patients, resulting in significantly shorter incubation periods than those due to sporadic CJD inocula. These findings are interpreted and discussed in terms of possible differences in the temporospatial evolution of damage to the brain, and of accelerated induction of polymerized amyloid protein by its mutationally altered template precursor.

Age Factors↗
PubMed1992

Candidate biomarkers for application as intermediate end points of lung carcinogenesis.

The need for validated intermediate end point markers to facilitate lung cancer chemointervention research is compelling. Three major classes of lung markers are relevant for this application. Since lung cancer includes four distinct histologies, markers that map degrees of histologic differentiation are important. Many of the markers for squamous differentiation overlap with the candidates for application in the study of head and neck cancer. Production of tissue-specific cell products especially for surfactant or CEA is of interest, because the gene structure is known and many differentiation-related polymorphisms exist. This strategy would be useful for adenomatous type tissue. A second type of marker is the broad group of differentiation markers. The carbohydrate or blood group-like antigens comprise a representative example. Carbohydrate structures are expressed in a specific sequence during fetal processes, and this sequence appears to reverse with the development of a cancer. Retrodifferentiation of specific differentiation markers is the basis of a major effort to effect earlier lung cancer detection using sputum immunocytochemistry. The final class includes markers which affect either positive or negative aspects of growth. Candidates in this area include growth factors or their receptors, or genes that regulate growth. If the intermediate end point marker reflects tumor biology and that biology is in the causal path of tumor progression, serial observation of that parameter should indicate the success of the intervention. In all three of these examples, the clinical material to be analyzed could be sputum specimens, bronchial biopsies or resected lung tissue. Systematic analysis of these markers in context of intervention trials is required to validate their utility.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1992

Voluntary stimulus-sensitive jerks and jumps mimicking myoclonus or pathological startle syndromes.

Five patients who presented with stimulus-induced jerking as part of an apparent myoclonic or pathological startle syndrome are reported. Neurophysiological observations in these patients suggested the jerks were voluntary in origin. These included (a) variable latencies to the onset of stimulus induced jerks, (b) latencies were greater than that seen in reflex myoclonus of cortical or brainstem origin, and were (c) longer than the fastest voluntary reaction times of normal subjects, (d) variable patterns of muscle recruitment within each jerk and, (e) significant habituation with repeated stimulation. It is argued that these features are consistent with a voluntary origin for the jerks and enable them to be distinguished from the stereotyped electrophysiological characteristics of myoclonus of cortical and brainstem origin. Electrophysiological recordings may help identify patients with this form of psychogenic movement disorder.

Adult↗
PubMed1992

Serum cortisol concentration and testosterone to cortisol ratio in elite prepubescent male gymnasts during training.

Serum cortisol concentrations and testosterone:cortisol concentration ratios of eight prepubescent elite male gymnasts (mean age 10 years 11 months) and 11 controls (mean age 11 years 1 month) were examined during 5 consecutive training days. During this period, the gymnasts trained 3 h each day with moderate intensity mobility, strength and skill exercises while the controls were relatively sedentary. Blood samples were taken from all the boys in both groups before (1630 hours) and 30 min after (2000 hours) training on 4 days. Serum cortisol concentrations of the gymnasts were not significantly different from those of the controls throughout the experiment. Serum cortisol concentrations of both groups were significantly larger (P < 0.05) at 1630 hours than at 2000 hours, indicating that cortisol secretion followed the typical adult circadian change, seemingly unaltered by training. However, there was a significant decrease (P < 0.05) in the testosterone:cortisol ratio of the gymnasts when compared with controls from day 1 to day 3. After a rest on day 4 the testosterone: cortisol ratio of the gymnasts significantly increased (P < 0.05) but the ratio of the control group also increased indicating that there may have been some day-to-day change by factor(s) other than training. The most obvious factor which may have accounted for the unresponsiveness of serum cortisol concentration to the gymnastics training was that the exercise intensity was too low. However, several days of the training seemed to reduce the anabolic to catabolic balance but further experiments are needed to confirm this finding.

Child↗
PubMed1992

An insert mutation in the chromosome 20 amyloid precursor gene in a Gerstmann-Sträussler-Scheinker family.

We report the finding of an insert mutation in the chromosome 20 amyloid precursor gene in a family with neuropathologically-verified, experimentally-transmitted Gerstmann-Sträussler-Scheinker syndrome (GSS). The insert consisted of 8 extra copies of a repeating octapeptide coding sequence in the region between codons 51 and 91; it was identified in the proband and a presently unaffected at-risk niece by full sequencing of the open reading frame, and was visualized electrophoretically in the proband and 6 of 12 at-risk relatives. Although affected members in this French-Breton family have shown a variety of clinical profiles, including durations of illness that ranged from 3 months to 13 years, all autopsied cases (including the patient with the shortest illness) have had the distinctive multicentric amyloid plaques that define GSS as a nosologic entity.

Adult↗
PubMed1992

Familial Creutzfeldt-Jakob disease in Chile is associated with the codon 200 mutation of the PRNP amyloid precursor gene on chromosome 20.

We have found the codon 200Lys mutation in 6 Chilean CJD families, including a family in the rural case cluster in Chillán. Thus, all 3 of the known clusters of CJD, in Slovakia, Libyan-born Israeli Jews, and Chile, are linked to the presence of the same mutation. The phenotypic features of the disease in these families are similar to those reported for other clustered or individual families elsewhere in the world. The heterogeneous genetic composition of the Chilean population interpreted in light of historical migration patterns suggests that the mutation may have entered Chile by Jewish emigration from Spain.

Adult↗
PubMed1992

Relation of rotation to egocentric and allocentric spatial learning in the rat.

In this experiment, we asked whether the relation between amphetamine-induced rotation and the learning and retention of left-right discrimination extends to allocentric spatial learning or is limited to egocentric spatial tasks. Rotation was established following injections of d-amphetamine sulfate, and rats were classified as nonrotators, midrotators, or strong rotators. Animals were successively trained on navigation in the Morris water maze (allocentric) and delayed spatial alternation in a water T-maze (egocentric). There were no rotation effects in water maze learning but rotators and nonrotators differed significantly in delayed spatial alternation learning but not relearning. Strong rotators learned more slowly than midrotators, clearly implying that rotational bias and directional learning are not linearly related. We show that it is egocentric spatial learning that is facilitated by a nigrostriatal dopamine asymmetry and extend the generality of the left-right discrimination findings.

Amphetamine↗
PubMed1992

Short report: comparison of two doses of balsalazide in maintaining ulcerative colitis in remission over 12 months.

In a four-centre prospective double-blind trial, 108 patients with ulcerative colitis in remission were randomized to receive balsalazide in doses of 3 g or 6 g/day for 12 months. The patients were assessed at 3-monthly intervals clinically, sigmoidoscopically and with routine haematology and biochemistry. Remission rates of 77% (3 g/day) and 68% (6 g/day) at 12 months were not significantly different. Intolerance reactions leading to withdrawal from the study occurred in only 9 patients (8%), all occurring in the first 7 weeks of the study. Balsalazide is therefore both highly effective in maintaining remission in ulcerative colitis and well tolerated in both conventional and high dosage (the latter equivalent to 5.5 g/day of sulphasalazine). In this study no distinct advantage in maintenance of remission has been found for the higher dose of balsalazide.

Adult↗
PubMed1992

Propriospinal myoclonus in multiple sclerosis.

The clinical and electrophysiological features of segmental myoclonus affecting the right arm and upper trunk are described in a patient with multiple sclerosis. Electrophysiological studies suggested that the myoclonus was propagated from a generator site in the cervical cord, where lesions were found using MRI. The spread of electromyographic activity in each myoclonic jerk was slow and variable. These findings are characteristic of propriospinal myoclonus, which has not been associated with multiple sclerosis previously.

Adult↗