Biomedical subjects

S Bingham

Publications and source records attributed to S Bingham.

105 records · Page 6Linked to original sources

PubMed1981

Dose-related effects of flurazepam on human sleep-walking patterns.

Two consecutive nights of flurazepam at each of 15, 26, and 45 mg were compared to placebo in a Latin-square double-blind crossover design using 24 healthy young-adult males. Flurazepam had significant hypnotic effects on objective and subjective measures of efficacy: shorter sleep latency, longer sleep time, and fewer awakenings. It also induced morning sedation along with decrements in cognitive performance. Flurazepam had dose-related impacts on both human and computer-scored EEG-EOG parameters: less stages 3 + 4 and decreased EEG delta, less stage 1 REM and decreased REM density, more stage 2 and increased EEG spindling. Also, EEG alpha and movement artifact were decreased and EEG beta was increased. Only a few of the EEG-EOG variables and none of the subjective indices had cumulative changes on the two drug nights. Stage shifting was unaffected at the two lower doses on the first night but decreased at all three dose levels on the second night; percent stages 3 + 4 was unaffected on the first night but decreased at all dose levels on the second night. The rate of delta waveform activity was also diminished by a greater amount on the second night. This study conclusively established that flurazepam affects the EEG-EOG architecture of sleep on each of the first two nights of administration.

Adult↗

PubMed1981

The diet of individuals: a study of a randomly-chosen cross section of British adults in a Cambridgeshire village.

1. The dietary intakes of sixty-three adults, randomly-selected from the electoral role of a large village near Cambridge, have been measured using the weighed-intake technique for 7 d. 2. Mean (+/- SD) daily intakes (g) for men and women respectively were: energy (MJ) 10.0 +/0 2.4, 8.2 +/- 2.1; fat 104 +/- 27, 90 +/- 27; protein 77 +/- 20, 67 +/- 16; carbohydrate 285 +/- 81, 229 +/- 74; sucrose 91 +/- 47, 57 +/- 33. 3. When interviewed at the end of the study 40% of subjects said they were watching their weight. 4. Women ate less food over all than men, and proportionately less potato and bread, and used only one-third as much sugar in drinks, probably in an attempt to control their weight. Men took considerably more alcohol than the women. In the age-group 20-39 years alcohol provided 9% (1.0 MJ/d) of the total energy intake in the men. 5. Wide variation in the intake of nutrients was observed amongst the individuals. For vitamin C and fibre intake this was partly partly explained by seasonal variation but for most nutrients total energy intake and food choice were the main determinants. The range of intakes of nutrients such as fat was similar in these individuals to that seen amongst countries internationally. It is suggested that if differences in nutrient intake amongst the various populations of the world can be associated with disease risk, then the same interpretation should be possible in individuals.

Adult↗

PubMed1981

Dose-related effects of phenobarbitone on human sleep-waking patterns.

1 Twenty-four healthy male subjects had two consecutive drug nights at 2-week intervals using placebo and 80, 140 and 240 mg doses of phenobarbitone in a double-blind cross-over design. 2 Phenobarbitone produced significant dose-related decreases in sleep latency and number of awakenings, along with increased total sleep time. 3 Both subjective and objective measures of sleep indicated the presence of cumulative (first v second night) effects of phenobarbitone, especially decreases in the number of awakenings and in delta waveform activity. 4 Measures of REM sleep were highly sensitive to phenobarbitone. The high dose decreased REM density to 30% of baseline on the first night and to 18% on the second night. 5 EEG alpha activity was decreased, beta activity was increased and sigma spindle activity was unaffected by phenobarbitone during sleep. 6 Subjects experienced some impairment of cognitive performance along with residual sedation the following morning.

Adult↗

PubMed1979

Events surrounding the early development of Euglena chloroplasts. 15. Origin of plastid thylakoid polypeptides in wild-type and mutant cells.

Techniques are described for the isolation of plastid thylakoid membranes from light-grown and dark-grown cells of Euglena gracilis var. bacillaris, and from mutants affecting plastid development. These membranes, which have minimal contamination with other cell fractions, are localized in sucrose gradients by using the thylakoid membrane sulfolipid as a specific marker. The plastid thylakoid membrane polypeptides isolated from these membranes were separated on SDS polyacrylamide gels and yielded patterns containing 30-40 polypeptides. Light-grown strain Z gave patterns identical with bacillaris. Since the plastid thylakoid polypeptide patterns obtained from dark-grown wild-type cells and from a bleached mutant W3BUL in which plastid DNA is undetectable are identical, it appears that the proplastid thylakoid polypeptides of wild-type cannot be coded in plastid DNA and are probably coded in nuclear DNA. The plastid thylakoid polypeptide patterns obtained from various dark-grown mutants, making large but abnormal chloroplasts, show a correlation between the amount of chlorophyll formed and the amount of a plastid thylakoid polypeptide thought to be associated wtth one of the pigment-protein light-harvesting complexes. Treatment with SAN 9789 (4-chloro-5-(methylamino)-2(alpha, alpha, alpha,-trifluoro-m-tolyl)-3-(2H(pyridazinone) known to block carotenoid synthesis at the level of phytoene, causes a progressive loss of all plastid thylakoid polypeptides during growth in darkness and results in the establishment of a new, lowere steady-state level of sulfolipid. At least ten of the plastid thylakoid polypeptides become labeled when isolated chloroplasts are supplied with radioactive amono acids; of these six are undectable in W3BUL and are, therefore, candidates for coding by plastid DNA.

Chloroplasts↗

PubMed1979

Events surrounding the early development of Euglena chloroplasts. 16. Plastid thylakoid polypeptides during greening.

Using sulfolipid to locate plastid thylakoid membranes in gradients from dark-grown resting cells it has been possible to study the plastid thylakoid membrane polypeptides of Euglena gracilis var. bacillaris undergoing light-induced chloroplast development. All plastid thylakoid bands seen in dark-growing wild-type cells and in mutant W3BUL in which plastid DNA is undetectable, are observed to increase in amount during plastid development. Others, which are undetectable in dark-grown wild-type and W3BUL increase greatly during plastid development and appear to be those associated with pigment-protein complexes. The data obtained from experiments where the polypeptides were labeled with 35S during development, either continuously or in pulses, were consistent with these findings. Cycloheximide strongly inhibited the increases in amount in all bands and chloramphenicol or streptomycin produced a lower level of inhibition in all bands indicating tight control of theformation of each plastid membrane constituent by the others. The formation of a polypeptide band of 25 000 molecular weight, thought to be a part of a pigment-protein complex of the thylakoid, and chlorophyll synthesis were inhibited identically by these antibiotics.

Chloramphenicol↗

PubMed1979

Dietary fibre and regional large-bowel cancer mortality in Britain.

The relationship between food intake and cancer of the large bowel was assessed by calculating the average intakes of foods, nutrients and dietary fibre in the different regions of Great Britain and relating these to the regional pattern of death from colon and rectal cancers between 1969 and 1973. No significant associations were found with the consumption of fat, animal protein or beer, nor with current estimates of total dietary fibre intake. Average intakes of the pentose fraction of total dietary fibres, and of vegetables other than potatoes, were negatively correlated with the truncated age- and sex-standardized death rates from colon cancer (r = -0.960 and -0.940). Specific components of dietary fibre may therefore inhibit colon carcinogenesis.

Adult↗

PubMed1979

Intakes and sources of dietary fiber in the British population.

Intakes of dietary fiber and its different components have been measured in a random sample of the population in Cambridgeshire, England and compared with data from the British National Food Survey. Sixty-three men and women ages 20 to 80 were included in the sample. Total dietary fiber intake was 19.9 +/- 5.3 g/day compared with the calculated value of 19.7 g/day from the 1976 National Food Survey. There was a 4-fold range in fiber intake from 8 to 32 g/day; no significant trends with age or between men and women were detected. Vegetables supplied the majority of the fiber (41.3%); cereals 30.5%, and fruit and mixed sources 28.2%. Of the components of dietary fiber noncellulosic polysaccharide, cellulose, and lignin intakes were 13.8, 4.7, and 1.4 g/day, respectively. In the noncellulosic fraction, hexoses contributed 7.4 g, pentoses and uronic acids 3.3 and 3.0 g. Vegetables and unrefined cereals were the main sources of pentose. These intakes are low in comparison with limited international data from developing countries and of a similar order to those known in dietary experiments to produce low stool weights, slow transit time, and concentrated feces. They could readily be increased by simple dietary changes.

Adult↗

PubMed1979

Low-residue diets: a reappraisal of their meaning and content.

Dietary fibre appears to be the only constituent of food that markedly affects faecal weight and probably total colonic content in normal individuals. It is proposed that low-residue diets intended to reduce large-bowel contents should be renamed low-dietary-fibre diets and be put on a quantitative basis. A low-dietary-fibre diet would contain 10 g or less. Other dietary modifications may also be necessary in diseases causing malabsorption.

Animals↗

PubMed1978