Fat intake in Hong Kong Chinese children.

The people of Hong Kong are experiencing a transition in dietary practices and lifestyle that can be observed in the fat intakes of Hong Kong children as compared with those of their counterparts on mainland China. The studies described here include 1) a longitudinal and observational dietary survey beginning with a cohort of 174 newborns and concluding with 124 children at age 7 y; 2) a biochemical study of serum lipids in relation to dietary fat intake at age 7 y; 3) a chemical fatty acid analysis and comparison of duplicate meals collected from 20 Hong Kong and 20 mainland Chinese children at age 7 y; 4) a dietary assessment of 52 lactoovovegetarian children aged 4-14 y; and 5) a comparison of the growth of all subjects with US National Center for Health Statistics standards. About 30% of the total daily energy intake of Hong Kong Chinese children aged 1-7 y was contributed by fat-much more than that in the traditional Chinese diet. Growth of the children was not impaired, including that of children on the mainland and of those lactoovovegetarians in Hong Kong whose fat intakes were lower. Mean serum cholesterol of Hong Kong Chinese children at age 7 y was 4.59 mmol/L, significantly higher than that of their counterparts on the mainland, 4.16 mmol/L. Foods consumed in Hong Kong had a significantly lower ratio of 18:2 to 14:0. Nutritional deficiency was uncommon. Chinese children in Hong Kong had a dietary fat intake that was both quantitatively and qualitatively different from the traditional Chinese diet.

A 12-month comparative trial of auranofin and D-penicillamine in rheumatoid arthritis.

The oral gold salt auranofin, 6 mg per day, was compared with oral d-penicillamine, 500 mg per day, in a single-blind trial in 40 patients suffering with definite or classic rheumatoid arthritis. The patients were randomly allocated into the two therapeutic regimens (19 patients auranofin; 21 patients d-penicillamine) and monitored at a minimum of four-week intervals during the first year of treatment. Significant diminution in rheumatoid disease activity, as assessed by numerous clinical and laboratory parameters, was observed in both the auranofin- and penicillamine-treated groups. No significant differences existed for these parameters between the two groups, either initially or at the end of the trial period. Ten patients were lost from the trial over the 52-week period. Three subjects were withdrawn from the auranofin-treated group (increasing severity of rheumatoid arthritis at four weeks; severe diarrhea at four weeks; probable drug-related erosive gastritis at 40 weeks). Seven subjects were permanently withdrawn from the penicillamine-treated group (four, skin rashes four to eight weeks; one, heavy proteinuria at 24 weeks; one, therapeutic failure at 32 weeks; one, compliance failure at eight weeks), and treatment was temporarily withheld in three further patients because of thrombocytopenia (two) and proteinuria (one). We conclude that both drugs are effective in rheumatoid arthritis and that the lesser toxicity with auranofin will make it a valuable addition to our therapeutic armamentarium.

Incidence of major complications of neurolytic coeliac plexus block.

The number of neurolytic coeliac plexus blocks carried out in England and Wales over a 5 year period (1986-1990) was ascertained. The number of cases of the major complications of permanent paraplegia and/or loss of anal and bladder sphincter function following on from such blocks, over the same period of time, was also ascertained. The information was obtained by means of a questionnaire which was sent to most of the pain clinics in England and Wales. There were 2730 neurolytic blocks carried out over the 5 year period. The number of cases of permanent paraplegia following on from the blocks was four. Of these four cases, three of them also had loss of anal and bladder sphincter function--loss of sphincter function never occurred in isolation. The incidence of major complications following neurolytic coeliac plexus block was thus one case per 683 blocks.

Thyroid dysfunction and rheumatic diseases.

Musculoskeletal symptoms developing during the treatment of thyroid disease were studied in 150 patients; 17 developed a symptom complex of early morning stiffness together with shoulder girdle pain and weakness; similar symptoms were seen in only 3 of 100 controls. A prospective study of 16 patients with recent onset rheumatoid arthritis followed during the first 6 months of penicillamine therapy showed no changes in thyroid function tests. It is suggested that changing or abnormal thyroid status may precipitate or exacerbate musculoskeletal disease. Finally, in a retrospective study of 26 patients with both thyroid disease and rheumatoid arthritis, 4 patients had a simultaneous onset of both myxoedema and rheumatoid arthritis, the activity of which was greatly improved by correction of the hypothyroid state.

Local complications of thiopentone injection. A further report.

Cases of local complications following the injection of thiopentone and reported to Medical Defence Union and to the Medical Protection Society in the period 1970-77 were analysed. There was no case of gangrene distal to the site of injection, but two cases of isolated damage to nerves, muscles and tendons and two cases of local tissue necrosis at the site of injection. A comparison of the results of the present investigation with those of two previous investigations indicates that the frequency of such complications has diminished over the period 1957-77.

A method of gas chromatography using electron-capture detection for the determination of blood concentrations of halothane, chloroform and trichloroethylene.

A method of gas chromatography using electron-capture detection for the determination of the concentration of the halogenated anaesthetic agents halothane, chloroform and trichloroethylene in blood is described. The accuracy of the analysis (measured blood concentration as a percentage of the calculated concentration) was: Halothane (11 blood samples in the range 37.9-6.00 mg/100 ml), mean 100.7 (SD 2.27), range 97.3-104.0; (12 samples in the range 0.164-0.0045 mg/100 ml), mean 98.8 (SD 6.80), range 90.7-111.1. Chloroform (five blood samples in the range 63.6-7.40 mg/100 ml), mean 100.4 (SD 1.30), range 99.3-102.5. Trichloroethylene (five blood samples in the range 20.6-13.2 mg/100 ml), mean 101.6 (SD 1.60), range 99.6-104.0.

Protein Degradation in Lemna with Particular Reference to Ribulose Bisphosphate Carboxylase: II. The Effect of Nutrient Starvation.

The concept of ribulose bisphosphate carboxylase as a storage protein is not supported in the case of Lemna minor, where the enzyme appears to be particularly stable under conditions of nitrogen starvation. Total nutrient starvation in light and in the dark induced the degradation of this enzyme, but not at an enhanced rate compared with other leaf proteins and, surprisingly, darkness inhibited the degradation of chlorophyll which occurs with total nutrient starvation in the light. The data suggest that Lemna is not programmed to senesce in response to nutrient starvation. Differences in the pattern of protein degradation, which occurred under the stress conditions employed, are not consistent with a simple model of protein degradation in which the degradative system is assumed to be located in the vacuole. The data is best explained by a dual system in which cytosolic proteins are degraded by a vacuolar/lysosomal system and chloroplast proteins are degraded within the chloroplast. Whatever the system of degradation, our data do not support the proposed correlation between the rate of protein degradation and either protein charge or size.

Protein degradation in lemna with particular reference to ribulose bisphosphate carboxylase: I. The effect of light and dark.

Ribulose bisphosphate carboxylase from Lemna minor resembles the structure reported for the enzyme from other plants. When grown in the light, the enzyme appears to undergo little or no degradation, as measured by a double-isotope method. This situation is similar to that reported for wheat and barley, but is unlike that reported for maize, where the enzyme degrades at the same rate as total protein. Prolonged periods of darkness usually induce leaf senescence, characterized by the rapid degradation of chlorophyll and protein, with ribulose bisphosphate carboxylase undergoing preferential degradation. In L. minor there is selective protein degradation in the dark, but chlorophyll and ribulose bisphosphate carboxylase are stable when fronds are kept in the darkness for up to 8 days. It appears that Lemna is not programmed to senesce, or at least that darkness does not induce senescence in Lemna. Although there is no evidence for in vivo degradation or modification of ribulose bisphosphate carboxylase during prolonged periods of darkness, extracts from fronds which have been kept in the dark for periods in excess of 24 hours convert ribulose bisphosphate carboxylase to a more acidic form. The properties of the dark-induced system which acts on ribulose bisphosphate carboxylase, suggest that it may be a mixed function oxidase. The proposition that the selectivity of protein degradation is genetically determined, so that the rate at which a protein is degraded is determined by its charge or size, was tested for fronds grown in the light or maintained in the dark. There was no significant correlation between protein degradation and either charge or size, in light or dark.

Is protein degradation correlated with either the charge or size of Lemna proteins?

Evidence is presented that the organelles of Lemna minor do not degrade as functional units. The proteins of Lemna show wide differences in their rates of degradation and ribulose bisphosphate carboxylase (EC 4.1.1.39) has a particularly slow rate of degradation. Contrary to some earlier evidence, we found no correlation between the rate of soluble-protein degradation and either charge or size of proteins. We could find no correlation between protein degradation and subunit size in any of the organelles of Lemna.

The separation of proteins based on their age, for the study of protein degradation in Escherichia coli.

Density labelling with 2H2O has been used in association with isopycnic centrifugation to isolate proteins of known age from cultures of Escherichia coli. The physical properties of protein samples of known age have been examined to detect a correlation between specific properties and susceptibility to degradation. No evidence of a correlation between size, charge, thermodynamic properties or amino acid composition, on one hand, and susceptibility to degradation, on the other hand, was observed following step-down conditions of growth. However, the SH content of proteins in E. coli does appear to be correlated with their susceptibility to degradation.

Protein turnover in the attached leaves of non-stressed and stressed barley seedlings.

Protein turnover was examined, using tritiated water, in various 2-cm regions of 7-11-d-old, first leaves of barley (Hordeum vulgare). Differences were found between the regions in their protein turnover and their responses to stress. The rate constant for degradation for total protein was the same throughout the leaf and the average half-life (t1/2) of protein=approx. 220 h. Only in the older regions did a 24-h pulse of(3)H2O preferentially label protein with a t1/2 (90 h) considerably shorter than the t1/2 for total protein. 'Soluble' protein was degraded faster than 'insoluble' protein and contained an appreciable short-lived protein component observable by short-pulse labelling. The rate of protein synthesis was greatest in the cells of the youngest region and declined as each region aged. The mean rate of protein synthesis over the 4-d period was 4 and 7 nmol h(-1) of amino-N with respect to the regions 1-3 and 7-9 cm from the leaf tip. Seedlings, stressed by adding polyethylene glycol (2.0 MPa) to the roots, showed a marked loss of protein from the older leaf regions with only small losses in the younger regions. Amino acids accumulated in the younger region continuously whereas in the older region little accumulation occurred until day 3 of stress when proline levels increased. Protein synthesis was decreased by between 30% and 50% in all leaf regions. In the region 1-3 cm from the leaf tip, the rate of protein degradation of total protein was enhanced and equalled the rate of degradation of 24-h-pulse-labelled protein which was not itself significantly affected by stress (t1/2=approx. 90 h). In the region 3-5 cm, the degradation of both 4-d and 24-h-labelled protein was enhanced by stress to rates similar to those found in the region 1-3 cm. This was largely through increases in the degradation of the 'insoluble' protein, but the degradation of 'soluble' protein was also raised. Protein degradation in the region 7-9 cm was not affected by stress.

Synthesis of oxalic Acid by enzymes from lettuce leaves.

A rapid purification of lactate dehydrogenase and glycolate oxidase from lettuce (Lactuca sativa) leaves is described. The kinetics of both enzymes are reported in relation to their possible roles in the production of oxalate. Lettuce lactate dehydrogenase behaves like mammalian dehydrogenase, catalyzing the dismutation of glyoxylate to glycolate and oxalate. A model is proposed in which glycolate oxidase in the peroxisomes and lactate dehydrogenase in the cytosol are involved in the production of oxalate. The effect of pH on the balance between oxalate and glycolate produced from glyoxylate suggests that in leaves lactate dehydrogenase may function as part of an oxalate-based biochemical, pH-stat.

The molecular basis of the selectivity of protein degradation in stressed senescent barley (Hordeum vulgare cv. Proctor) leaves.

The molecular basis for the selectivity of protein degradation has been examined in osmotically stressed and senescent barley leaves. Relatively weak correlations between the in-vivo rate of loss of enzyme activity, and the charge and molecular weight of the enzymes ahve been detected. We interpret these correlations as supporting the view that the selectivity of enzyme degradation is the result of the physical properties of the enzymes being degraded. The weakness of the correlates is taken to mean that a number of properties which contribute to the selectivity are independent of one another. Under in-vitro conditions (autolysis at 0° C), the loss of enzyme activity was weakly correlated with the charge of the enzymes. However, there was a general similarity between the in-vivo pattern of loss of enzyme activity and the in-vitro patterns under a number of conditions. Furthermore double-isotope experiments demonstrated that the in-vivo degradation of soluble protein was reflected by in-vitro degradation under a number of conditions. Consequently we conclude that the selectivity of protein degradation is largely independent of the nature of the proteolytic system.