Urinary organic acids in man. II. Effects of individual variation and diet on the urinary excretion of acidic metabolites.

1976 ◽  
Vol 22 (8) ◽  
pp. 1288-1291 ◽  
Author(s):  
R A Chalmers ◽  
M J Healy ◽  
A M Lawson ◽  
R W Watts
Keyword(s):  
Urinary Excretion ◽  
Individual Variation ◽  
Normal Population ◽  
Dietary Factors ◽  
Large Individual ◽  
Dietary Composition ◽  
Population Surveys ◽  
Urinary Organic Acids ◽  
Normal Ranges ◽  
Individual Variations

Abstract We have assessed individual variations in urinary acidic metabolite excretion and the effects of extreme alterations in dietary composition on these metabolites in selected normal persons who we considered representative of the general ambulant normal population. Extreme dietary alterations produced relatively small changes in the patterns or amounts of metabolite excretion, but large individual within-subject variations were observed. Our results indicate that variation in the ranges of excretion for the normal population mainly depend on individual metabolic variations rather than on dietary factors, and provide a basis for the assessment of the normal ranges determined from population surveys. Our results are discussed in relation to previous studies on the variability of urinary acidic metabolite excretion in man.

Urinary organic acids in man. III. Quantitative ranges and patterns of excretion in a normal population.

1976 ◽  
Vol 22 (8) ◽  
pp. 1292-1298 ◽  
Author(s):  
R A Chalmers ◽  
M J Healy ◽  
A M Lawson ◽  
J T Hart ◽  
R W Watts
Keyword(s):  
Organic Acids ◽  
Urinary Excretion ◽  
Frequency Distribution ◽  
Clinical Condition ◽  
Human Subjects ◽  
Normal Population ◽  
Distribution Patterns ◽  
Relative Significance ◽  
Urinary Organic Acids ◽  
Normal Human

Abstract We studied the urinary excretion of organic acids by normal human subjects in an ambulant normal population, chosen without conscious bias. Quantitative ranges and frequency distribution patterns of excretion are reported, as a basis on which to compare results obtained for patients whose clinical condition suggests that their excretion values may be abnormal. The quantitative valuse we observed enable the relative significance of different urinary anionic metabolites to be assessed, including the recently identified aldonic and deoxyaldonic acids. The frequency distribution patterns observed are discussed briefly.

Normal ranges for urinary excretion of calcium and magnesium in portuguese children

1992 ◽  
Vol 6 (3) ◽  
pp. 313-313 ◽  
Author(s):  
Gabriela Sa ◽  
H. Proen�a ◽  
F. C. Rosa
Keyword(s):  
Urinary Excretion ◽  
Normal Ranges ◽  
Calcium And Magnesium

Mental stress and cognitive performance do not increase overall level of cerebral O2 uptake in humans

1992 ◽  
Vol 73 (2) ◽  
pp. 420-426 ◽  
Author(s):  
P. L. Madsen ◽  
J. F. Schmidt ◽  
S. Holm ◽  
H. Jorgensen ◽  
G. Wildschiodtz ◽  
...  
Keyword(s):  
Mental Stress ◽  
Mental Arithmetic ◽  
Statistical Significance ◽  
Plasma Catecholamines ◽  
Synaptic Activity ◽  
Large Individual ◽  
Cerebral Metabolic Rate ◽  
Mental Activation ◽  
Individual Variations ◽  
Lactate Output

We measured cerebral metabolic rate of oxygen (CMRO2), cerebral blood flow (CBF), and cerebral lactate output during rest, during the execution of mental arithmetic, and during mental stress induced by physical and psychological annoyance. Measurements were performed in healthy volunteers by use of the Kety-Schmidt technique with 133Xe as the inert gas. Electroencephalographic desynchronization and highly significant increases in plasma catecholamines and heart rate verified that the test measurements were performed during conditions differing distinctly from the resting state. In accordance with an earlier study (Sokoloff et al. J. Clin. Invest. 34: 1101–1108, 1985), a minimal and nonsignificant 1% reduction of global CMRO2 during mental arithmetic was observed, signifying that this form of mental activation was unassociated with any detectable increase in overall cerebral synaptic activity. Mental stress induced a slight but highly significant (P less than 0.002) 6% reduction in global CMRO2. This finding is in contrast to results from earlier investigations and contradicts the generally accepted notion of an association between mental arousal and a diffuse upregulation of cerebral synaptic activity. During mental arithmetic and mental stress, cerebral lactate output increased by 207 and 344%, respectively, but because of large individual variations in the measured responses, the elevations reached statistical significance only during mental arithmetic.

scholarly journals Impaired skeletal growth in mice with haploinsufficiency of IGF-I: genetic evidence that differences in IGF-I expression could contribute to peak bone mineral density differences

2005 ◽  
Vol 185 (3) ◽  
pp. 415-420 ◽  
Author(s):  
S Mohan ◽  
D J Baylink
Keyword(s):  
Bone Mineral Density ◽  
Bone Mineral ◽  
Individual Variation ◽  
Normal Population ◽  
Quantitative Computed Tomography ◽  
Control Group ◽  
Mineral Density ◽  
Peak Bone Mineral Density ◽  
Igf I ◽  
Peak Bmd

Although it is well established that there is considerable inter-individual variation in the circulating levels of IGF-I in normal, healthy individuals and that a genetic component contributes substantially to this variation, the direct evidence that inter-individual variation in IGF-I contributes to differences in peak bone mineral density (BMD) is lacking. To examine if differences in IGF-I expression could contribute to peak BMD differences, we measured skeletal changes at days 23 (prepubertal), 31 (pubertal) and 56 (postpubertal) in mice with haploinsufficiency of IGF-I (+/−) and corresponding control mice (+/+). Mice (MF1/DBA) heterozygous for the IGF-I knockout allele were bred to generate +/+ and +/− mice (n=18–20 per group). Serum IGF-I was decreased by 23% (P<0.001) in mice with IGF-I haploinsufficiency (+/−) group at day 56 compared with the control (+/+) group. Femoral bone mineral content and BMD, as determined by dual energy X-ray absorptiometry, were reduced by 20% (P<0.001) and 12% respectively in the IGF-I (+/−) group at day 56 compared with the control group. The peripheral quantitative computed tomography measurements at the femoral mid-diaphysis revealed that periosteal circumference (7%, P<0.01) and total volumetric BMD (5%, P<0.05) were decreased significantly in the +/− group compared with the +/+ group. Furthermore, serum IGF-I showed significant positive correlations with both areal BMD (r=0.55) and periosteal circumference (r=0.66) in the pooled data from the +/+ and +/− groups. Our findings that haploinsufficiency of IGF-I caused significant reductions in serum IGF-I level, BMD and bone size, together with the previous findings, are consistent with the notion that genetic variations in IGF-I expression could, in part, contribute to inter-individual differences in peak BMD among a normal population.

Agarose gel electrophoresis with nitroblue tetrazolium coloration for determination of glycated lipoproteins in serum from diabetics

1990 ◽  
Vol 36 (1) ◽  
pp. 65-69 ◽  
Author(s):  
K Kobayashi ◽  
N Ogasahara ◽  
T Sakoguchi ◽  
M Kimura ◽  
K Taniuchi ◽  
...  
Keyword(s):  
Nitroblue Tetrazolium ◽  
Atherogenic Index ◽  
Large Individual ◽  
Diabetic Patients ◽  
Agarose Gel ◽  
Simple Method ◽  
Color Development ◽  
Normal Individuals ◽  
Individual Variations ◽  
Gel Film

Abstract We describe a simple method for determining glycated lipoproteins (glc LPs) in serum by agarose gel film electrophoresis, with color development with nitroblue tetrazolium. The resulting blue bands on the film were measured densitometrically at 545 nm to quantify alpha-, pre beta-, and beta-glc LPs. Each glc LP concentration (mmol/L) was calculated from the resulting percentage multiplied by the value for serum fructosamine. Only glc beta-LP was significantly correlated with the atherogenic index: low-density LP-cholesterol/high-density LP-cholesterol (r = 0.545, P less than 0.01). The concentration of glc beta-LP in sera from diabetics was 2.2-fold higher (0.84 mmol/L) than that (0.38 mmol/L) in normal individuals. Diabetic patients with complications had higher concentrations of glc beta-LP, with large individual variations, than did patients without complications, the greatest concentration (1.02 mmol/L) being found in patients with diabetic retinopathy and (or) nephropathy. The concentration of glc beta-LP (glc LDL) in serum seems to depend on the extent and duration of hyperglycemia; it may also be a useful diagnostic indicator of diabetic atherogenesis, microangiopathy (e.g., retinopathy or nephropathy), and other complications.

scholarly journals Development of comprehension of ironic utterances in 3- to 9-year-old Finnish-speaking children

2008 ◽  
Vol 12 (1) ◽  
pp. 55-69 ◽  
Author(s):  
Soile Loukusa ◽  
Eeva Leinonen
Keyword(s):  
Individual Variation ◽  
Age Groups ◽  
Large Individual ◽  
Literal Interpretation ◽  
Incorrect Answer ◽  
Significant Difference

Development of comprehension of ironic utterances in 3- to 9-year-old Finnish-speaking children This study explores the comprehension of simple ironic utterances in 210 Finnish children aged from 3 to 9 years. If the child answered the question correctly, he/she was asked to explain correct answers. The results indicated that there was large individual variation within age groups both in answers and explanations. In terms of correct answers there was a significant difference between 6- and 7-year-olds and in correct explanations between age groups of 3-4, 6-7 and 7-8. Analysis of incorrect answers showed that literal interpretation of an utterance was the most common incorrect answer type in all age groups. Totally irrelevant answers occurred only in children aged 3 and 4. In terms of incorrect explanations, "turntaking" and "incorrect focus" categories were the most common incorrect explanation types. Contrary to previous studies, in this study already some of the 3- and 4-year-olds showed an emerging ability to comprehend irony.

scholarly journals Comparative digestion of timothy (Phleum pratense) fibre by ruminants, equines and rabbits

1982 ◽  
Vol 47 (2) ◽  
pp. 267-272 ◽  
Author(s):  
Peter Udén ◽  
Peter J. Van Soest
Keyword(s):  
Body Weight ◽  
Individual Variation ◽  
Dry Matter ◽  
Phleum Pratense ◽  
Dry Matter Intake ◽  
Large Individual ◽  
Faecal Output ◽  
True Digestibility

1. The abilities of cattle, sheep, goats, equines and rabbits to digest mature timothy (Phleum pratense) hay were compared. Apparent digestibilities were partitioned into true digestibility, metabolic faecal output (MFO) and fibre digestibility. The aim of the study was to determine the relative effects of fermentation site (among groups) and of body-weight (within groups) on the efficiency of digestion.2. The ruminants were superior to equines, which were in turn superior to rabbits, in digesting fibre components of the hay. A large individual variation in digestibility was noted only for the equines. Increasing body-weight was associated with higher digestibility in ruminants, but no such trends were seen in the non-ruminants.3. The MFO expressed as a proportion of dry matter intake gave similar values for all groups (0·085–0·118). As a proportion of available microbial substrate originating from the feed, the values were found to be 0·167 for the ruminant, 0·425 for the equines and 2·13 for the rabbits. The value for the rabbits shows that their lower tract microflora must obtain energy from non-fibre components of the feed. No appreciable digestion of the generated microbes by the host was suggested by the values obtained for the equines.

Intra-Individual Variation in Serum AZT Concentration is Not Related to Intestinal Absorption or Small Intestinal Inflammatory Changes in Human Immunodeficiency Virus-Infected Subjects

1997 ◽  
Vol 8 (4) ◽  
pp. 327-332 ◽  
Author(s):  
RA Sherwood ◽  
JT Marsden ◽  
CA Stein ◽  
S Somasundaram ◽  
C Aitken ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Urinary Excretion ◽  
Intestinal Permeability ◽  
Absorptive Capacity ◽  
Individual Variation ◽  
Half Life ◽  
Intestinal Inflammation ◽  
Immunodeficiency Virus ◽  
Small Intestinal ◽  
Inflammatory Changes

3′-Azido-3′-deoxythymidine (AZT; zidovudine) either alone or in combination with didanosine or another nucleoside analogue is the first-line treatment for patients with human immunodeficiency virus (HIV) infection, many of whom have concurrent gastrointestinal (GI) disease. This study assessed whether the absorption of AZT was affected by GI disease. The absorption and pharmacokinetics of AZT in 23 HIV-infected individuals was measured after a single dose of AZT and was related in 12 patients to small intestinal function. Levels of AZT and its metabolite 5′-glucopyranuronosylthymidine (G-AZT) were measured by radioimmunoassay. Intestinal permeability was assessed by differential urinary excretion of orally administered lactulose/1-rhamnose; absorptive capacity was measured simultaneously by the urinary excretion of 3-o-methyl-D-glucose, d-xylose and 1-rhamnose. Small intestinal inflammation was assessed by faecal excretion of indium-labelled neutrophils. Peak levels of AZT in serum varied between 170 and 1820 ng mL−1. The metabolite G-AZT was present in serum at peak concentrations varying from 1020 to 9930 ng mL−1. There was up to a sevenfold variation in the area under the curve (AUC). The time to maximum serum concentration for AZT was between 30 and 120 min, with an absorption half-life of between 2 and 38 min. The median elimination half-life was 57 min (range 46–72 min), close to the predicted half-life of 60 min. Intestinal permeability was increased in six of the 12 subjects studied and eight had evidence of reduced absorptive capacity. Ten of the 12 patients had evidence of small intestinal inflammation. We concluded that neither changes in permeability nor absorptive capacity influenced the absorption of AZT. There was no relationship between the presence of intestinal inflammation and AZT absorption. This study showed a significant intra-individual variation of serum AZT levels which cannot be explained on the basis of altered intestinal absorptive capacity or intestinal inflammatory changes.

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