摘要:

Variations of lactose and oligosaccharides in human milk were studied over a 3-month lactation period by dialysis, chromatography on Bio-gel P-2 column, paper chroma-tography, colorimetric analysis and gas chromatography. Milk samples were collected from donors of various blood and secretor types. An increase in the concentration of lactose was noted: 59.25 ± 1.61 to 72.17 ± 1.35 g/l for the group of secretor A secretor LeaLeb individuals, and from 62.25 ± 1.35 to 73.15 ± 3.45 g/l for the group of secretor H secretor Lea Leb individuals. A decrease in the concentration of oligosaccharides was also found: from 16.71 ± 0.99 to 7.90 ± 1.29 g/l and from 18.51 ± 0.74 to 7.33 ± 0.65 g/l, respectively, for these same groups. In secretor H nonsecretor Lewis individuals, the concentration of lactose increased from 67.97 ± 3.09 to 77.42 ± 1.88 g/l, and the concentration of oligosaccharides decreased from 13.27 ± 0.40 to 3.47 ± 0.33 g/l. Analysis of oligosaccharide composition by chromatography showed that variations are in relation to the secretor Lewis type. All oligosaccharides decreased equally throughout the lactation period, regardless of the blood group. The decrease was more rapid, however, in the nonsecretor Lewis individuals. In these individuals, the absence of certain oligosaccharides is not compensated by an overproduction of the other oligosaccharides present or by biosynthesis of structurally different oligosaccharides. The origin of these oligosaccharides i

ISSN:0250-6807    

DOI:10.1159/000176947

出版商:S. Karger AG    

年代:1985

数据来源: Karger

ISSN:0250-6807    

DOI:10.1159/000176998

出版商:S. Karger AG    

年代:1985

数据来源: Karger

ISSN:0250-6807    

DOI:10.1159/000176999

出版商:S. Karger AG    

年代:1985

数据来源: Karger

ISSN:0250-6807    

DOI:10.1159/000177000

出版商:S. Karger AG    

年代:1985

数据来源: Karger

ISSN:0250-6807    

DOI:10.1159/000177002

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

From May 1976 until June 1982 a longitudinal study in 54 apparently healthy Austrian schoolchildren with a mean age of 11.2 years at their first visit was performed. The aim of this study was to determine if there are any age-related changes in serum lipids, lipoproteins and α-tocopherol concentrations during adolescence and whether a permanent relationship between lipoproteins and α-tocopherol can be observed. Total cholesterol showed a significant decrease from age 11 to 14 years in boys (from 195.5 ± 42.2 to 147.9 ± 40.3 mg/dl) as well as in girls (from 181.9 ± 29.7 to 144.1 ± 23.4 mg/dl); thereafter, a slight increase could be shown. Similar changes could be observed for LDL cholesterol. No significant sex differences were found either in total or in LDL cholesterol, whereas in HDL cholesterol concentrations, a decrease in boys between 12 and 14 years (from 58.4 ± 18.3 to 41.7 ± 10.8 mg/dl) and an increase in girls from 13 years onwards led to significantly lower values in boys than in girls from the age of 16 years onwards. No consistent changes could be shown for α-tocopherol blood levels. Nevertheless, a close relationship between total cholesterol and α-tocopherol could be observed during all our investigations (0.4695 ≤ r ≤ 0.7300, p < 0.05) and, to a lesser degree, between LDL cholesterol and α-tocopherol. Significant correlations between α-tocopherol and HDL cholesterol and between α-tocopherol and triglycerides occurred o

ISSN:0250-6807    

DOI:10.1159/000176948

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The oxygen consumption rates of virgin and lactating rats fed ad libitum were measured at temperatures ranging from 1 to 28 °C. The oxygen consumption rates of the virgin animals decreased progressively with increasing ambient temperature, but those of the lactating animals decreased slightly between 1 and 8 °C, remained approximately constant between 8 and 20 °C and fell rapidly above 20 °C. It is suggested that the fall in oxygen consumption rate above 20 °C in the lactating rats was due to a reduction in milk synthesis rate, and that the thermoneutral zone for normal lactation was 8–20 °C; this is a substantially cooler range than that of virgin rats (28–29 °C). The net energetic efficiency of milk production was calculated from the energy output in milk and the amount of energy used to produce milk (estimated from the oxygen consumption rates). The value obtained

ISSN:0250-6807    

DOI:10.1159/000176949

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The effects of two diets equal in protein content (12% of energy) but different in carbohydrates (80% of energy) or in fat (68% of energy) were studied in a changeover trial with 6 healthy young subjects. Each person was 2 weeks on each diet. Under the conditions of slight undernutrition and neutral temperature the balances of nitrogen, carbon and energy were assessed in 7-day collection periods, and according to 48-hour measurements of gaseous exchange (carbon-nitrogen balance method) by the procedures of indirect calorimetry. At isocaloric supply of metabolizable energy no differences were found in the retention of N, C and energy. The heat production calculated by indirect calorimetry was not significantly different with both diets. The lower body weight during the high-fat diet was due to higher sodium and water excretion. The high-fat diet resulted in lower fecal and higher urine excretion of nitrogen, but because of a compensative response no difference in nitrogen retention was observed between the two dietary regimens. The plasma concentrations of cholesterol, glucose and uric acid were higher with fat-rich diet; those of triglycerides were higher with carbohydrate-rich diet. The results demonstrate that the composition of the diet did not influence the energy balance.

ISSN:0250-6807    

DOI:10.1159/000176950

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Alterations in the relative proportions of very low density lipoprotein (VLDL) apoprotein C-III (apoC-III) isoforms have been previously observed under various dietary and metabolic states. This study was designed to evaluate the effects of a very high caloric restriction on plasma triglycerides and on the relative proportions of VLDL apoprotein C-II (apoC-II) and apoC-III isoforms in obese subjects. VLDL were isolated by preparative ultra-centrifugation from 12 obese women. ApoC-II and apoC-III subspecies were separated by analytical ultrathin-layer isoelectrofocusing. The mean body weight decreased significantly from 96.2 ± 8.7 to 90.6 ± 7.6 kg (p < 0.01). Mean total and VLDL triglycerides did not vary significantly. Apoprotein C-III2 (apoC-III1) as percentage of total apoprotein C increased (p < 0.01) and apoprotein CIII0 (apoC-III0) decreased (p < 0.01). Apoprotein C-III1 (apoC-III1) did not vary significantly. An inverse correlation was found between the percentage variation of apoC-III2 and that of apoC-III1 (r = -0.94; p < 0.01). The variations of apoC-III2 correlated positively (r = 0.83; p < 0.01), while those of apoC-III1 correlated inversely (r = -0.65, p < 0.025) with the changes of VLDL triglycerides. The apoC-III1 to apoC-III2 ratio as well as the apoC-III0 to apoC-III2 and apo C-III1 ratios decreased after diet (p from < 0.01 to < 0.001). Total apoC-III as well as apoC-III2 and apoC-III1 to apoC-II ratios did not vary. On the contrary, the apoC-III0 to apoC-II ratio decreased (p < 0.001). The data indicate that severe caloric restriction is associated with a modification in the relative proportions of VLDL apoC-III subspecies. Further studies are needed to define if these changes play a role in regulation of plasma triglycerides in ma

ISSN:0250-6807    

DOI:10.1159/000176951

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The assumption is currently made by international organisations that individuals of the same size living in the same environment and having the same mode of living will have the same energy requirements whatever their race. Reports of very low energy intakes are frequently doubted. To investigate possible racial differences the energy cost of standardised activities was measured in European, Asian, and African males under the same experimental conditions. Subjects were closely matched for height, weight and Quetelet index. The energy cost of each activity, lying, sitting and standing, was significantly higher, by 10–17%, in Europeans as compared to Asians and Africans, between whom no differences were found. Whether these differences are morphological or metabolic is discussed. It is concluded that differences in energy requirements do exist over and above those due to body size and activity.

ISSN:0250-6807    

DOI:10.1159/000176952

出版商:S. Karger AG    

年代:1985

数据来源: Karger