Blood Concentrations Of Nutrients Research Articles

Nutritional status and its response to treatment of children, with and without HIV infection, hospitalized for the management of tuberculosis

Background: The association of childhood tuberculosis (TB) and malnutrition is known, but treatment response, the influence of the acute-phase response (APR) and concomitant HIV infection are not well documented.Aim: To evaluate the nutritional response and APR in HIV-infected and uninfected children hospitalised for the treatment of TB and receiving standard anti-tuberculosis chemotherapy.Methods: During a study of the pharmacokinetics of standard anti-tuberculosis agents, anthropometric parameters were measured and blood concentrations of nutrients and C-reactive protein (CRP) determined at 1 and 4 months after initiation of chemotherapy.Results: 24 HIV-infected and 34 HIV-uninfected children were studied. On enrolment, 31·6% of HIV-infected and 2·9% of HIV-uninfected children were underweight, and 31·6% and 14·7%, respectively, were stunted. Mean values of weight, height/length, head circumference and mid-upper-arm circumference on enrolment and at 4-month assessment in HIV-infected and uninfected children did not differ. Mean triceps skinfold (TSF) (8·17 and 9·73 cm) and subscapular skinfold (SSF) thicknesses (5·75 and 7·5 cm) on enrolment differed significantly (P = 0·03 and P = 0·003); by 4 months, TSF had declined to 5·97 cm (P<0·001) and 8·87 cm (P = 0·05), respectively, and SSF to 5·57 cm (P = 0·79) and 6·73 cm (P = 0·04); the arm muscle area (AMA) was low in a majority of children on enrolment and remained so at the second assessment. CRP was raised in 66·6% and 53·3% of HIV-infected and -uninfected children on enrolment, but at 4-month assessment was raised in 63·2% and 15·2%, respectively. Other micronutrient and haematological findings probably reflect an APR, but no children had sub-normal zinc or magnesium values; most selenium and vitamin C and E values were normal. An elevated platelet count (>420×109/L) was significantly more common in HIV-uninfected children, and was still raised in 39% at 4 months.Conclusion: A majority of HIV-infected and uninfected children had an APR but it had resolved by 4 months in most HIV-uninfected children. In both groups, low and declining skinfolds and a persistently low AMA indicate a persistent disturbance of fat and protein metabolism, despite successful chemotherapy.

Variability characteristics and test selection in herd-level nutritional and metabolic profile testing.

Nutritional assessment based on animal response factors is the basis of essentially all dietary recommendations. Blood concentrations of nutrients, metabolites, and hormones are important animal response factors associated with nutriture, making blood analysis an important nutritional assessment technique. There are, however, numerous sources of variability, other than nutrition, affecting the concentration of blood analytes used in nutritional assessment. Minimizing the effects of non-nutrient sources of variability and maximizing the effects of nutritional variability is the objective in designing strategies for blood sampling and testing for nutritional assessment. Important non-nutrient sources of variability are age, sex, gestation stage, lactation stage and milk yield, and season. When interpreting test results, grouping animals by these characteristics is an important means of minimizing the effects of non-nutritional variability. Within these groups, it is important to take an adequate number of samples, generally starting out with at least seven. Finally, selecting appropriate tests is critical. Tests commonly used for clinicopathologic evaluations are not necessarily the best tests for nutritional assessment. Analytes should be chosen that are likely to have a large portion of their total variability caused by nutritional effects. This generally does not include those metabolites the blood concentrations of which are rigidly controlled by homeostatic forces.

Digestion of wheat protein in the preruminant calf: ileal digestibility and blood concentrations of nutrients

Three milk substitute diets (control, SWP76 and SWP36) were given to ileo-caecal cannulated preruminant calves. In these diets, skim milk powder was either the only protein source or totally or partially (48%) replaced by a mixture of solubilized wheat protein concentrate (SWP) and whey powder (76% and 24%; crude protein basis), respectively. The apparent ileal digestibility of nitrogen was lower ( P<0.02) with the SWP76 and SWP36 diets than with the control (0.85, 0.89 and 0.91, respectively) and also with the SWP76 than with the SWP36. Similar trends were observed for most amino acids (AA), except for cystine which showed higher values with the SWP-containing diets than with the control ( P<0.05). Assuming the true digestibility of milk protein was total, the real digestibility would be ≥0.95 for most essential AA of SWP+whey proteins. Repetitive fractions rich in glutamine, proline and phenylalanine, which are abundant in wheat protein, appeared to partially escape digestion. The amount of undigested endogenous protein could also be slightly higher (7–17%) with the SWP-containing diets than with the control. The pre-feeding plasma concentrations were lower ( P<0.001) with the SWP76 than with the control for triglycerides and similar with both diets for free methionine and threonine. In contrast, most post-feeding values were higher ( P≤0.05) with the SWP76 than with the control. The SWP36 diet gave values or patterns intermediate to those recorded with the other diets. Most of these differences were consistent with a faster abomasal emptying for fat and protein with the SWP-containing diets, especially the SWP76. As far as threonine and methionine were concerned, they could also have been increased by the fact that larger parts of these AA were free in the SWP-containing diets.