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Young adults who ingested 1.3 g/kg/day of either animal protein-rich diet or a soy protein-rich diet did not reveal a significant difference in the level of protein turnover. Whole-body protein turnover was estimated in the fed state using the glycine test at the end of the two-week controlled diet period. The results have suggested that properly processed soy protein is fully capable of meeting human amino acid and nitrogen needs.

The 15N leucine-dilution method effectively differentiates between the exogenous and the endogenous contributions to nitrogen fluxes in the human intestines. It can be used with or without labeled dietary protein to compare the digestion and absorption of meals at different levels in the intestine. An estimation of exogenous nitrogen and amino acids 300 min after yoghurt ingestion shows that 62% plus or minus 30% of the exogenous nitrogen and 75% plus or minus 12% of amino acids are absorbed in the upper jejunum.

Compartmental modeling of postprandial dietary nitrogen distribution in humans. Am J Physiol Endocrinol Metab 279: E161-E175, 2000.--A linear 11-compartment model was developed to describe and simulate the postprandial distribution of dietary nitrogen. The values of its 15 constant diffusion coefficients were estimated from the experimental measurement of [sup.15]N nitrogen kinetics in the intestine, blood, and urine after the oral administration of [sup.15]N-labeled milk protein in humans. Model structure development, parameter estimation, and sensibility analysis were achieved using SAAM II and SIMUSOLV softwares. The model was validated at each stage of its development by testing successively its a priori and a posteriori identifiability. The model predicted that, 8 h after a meal, the dietary nitrogen retained in the body comprised 28% free amino acids and 72% protein, ~30% being recovered in the splanchnic bed vs. 70% in the peripheral area. Twelve hours after the meal, these values had decreased to 18 and 23% for the free amino acid fraction and splanchnic nitrogen, respectively. Such a model constitutes a useful, explanatory tool to describe the processes involved in the metabolic utilization of dietary proteins. mathematical model; parameter estimation; kinetics; protein metabolism; optimization

The evolution and luminal effects of different quantities of casein and beta-lactoglobulin were investigated in the upper jejunum of 35 volunteers who ingested 400 mL water with either beta-lactoglobulin or casein in either low or high doses (72.6 mmol N, Lbetalg; 71.7 mmol N, LCas; 368.2 mmol N, Hbetalg; 386.8 mmol N, HCas). The flow rate of the liquid effluents as well as the nitrogen movements were measured and the exogenous ([15N]) and endogenous nitrogen fractions analyzed in the upper jejunum after milk protein ingestion. The basal jejunal liquid flow rate (mL/min) was 3.88 +/- 1.84 and peaked in the 0-20 min period for water (9.92 +/- 3.72) and Lbetalg (7.27 +/- 3.08) and during the 20-40 min period for LCas (5.69 +/- 2.49), HCas (6.32 +/- 1.85), and Hbetalg (6.11 +/- 2.31). One hour after water, LCas, Lbetalg, Hbetalg, and HCas ingestion, 100%, 95%, 85%, 71%, but only 38% of the liquid phase of the meal were passed through the jejunum, respectively. The flow rate of the endogenous nitrogen was 12.93 +/- 5.22 mmol N/h before meal ingestion; remained unchanged after water, LCas, or Hbetalg ingestion; but increased significantly (P < 0.05) after Lbetalg and HCas ingestion. The net disappearance of exogenous nitrogen in the upper jejunum 240 min after HCas, Lbetalg, LCas, and Hbetalg ingestion was 82.6 +/- 9.5%, 61.6 +/- 9.6%, 58.4 +/- 14.7%, and 44.7 +/- 24.4%, respectively. The exogenous fraction of protein nitrogen recovered in the upper intestinal lumen represented 43.3% of the ingested Hbetalg nitrogen, but only 4.9% of the ingested HCas nitrogen. In conclusion, casein and beta-lactoglobulin present differences in both the intestinal kinetics of amino acid delivery and in the nature of the products in the intestinal lumen. These differences have to be taken into account from both nutritional and physiologic points of view for the utilization of these proteins in humans. (c) 1996 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

Drivers of environmental change and policy processes are pushing the sub-Saharan African region to do more in the struggle against climate change as the region suffers most from climate change impact. To this end, this study investigates how the interaction effects of a sustainable financing model in energy use influence carbon emissions in Sub-Saharan African economies. It is based on the theory that energy consumption is determined by increased economic financing. Panel data analysis of thirteen countries from 1995 to 2019 is used to explore the interaction effect on CO2 emissions, taking a market-induced energy demand perspective. The study employed the fully modified ordinary least squares technique, removing all heterogeneity effects in a panel estimation. The econometric model was estimated with (and without) the interaction effect. The study finds support for the Pollution-Haven hypothesis and the Environmental Kuznets "inverted U-shaped" Curve Hypothesis in the region. It identifies a long-run relationship between the financial sector, economic activity, and CO2 emissions, with fossil fuel consumption in industrial activities increasing CO2 emissions by about 2.5 times. However, the study also reveals that the interactive effect of financial development can significantly reduce CO2 emissions, providing important implications for policymakers in Africa. The study suggests regulatory incentives to encourage banking credit intermediation for environmentally friendly energy sources. This research makes a valuable contribution to understanding the environmental impact of the financial sector in sub-Saharan Africa, an area that has received limited empirical attention. The findings highlight the relevance of the financial sector for policy formulation in addressing environmental issues in the region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2023. Published by Elsevier Ltd. All rights reserved.)

Background: Nuclear transfer has the potential to become one strategy for fish genetic resources management, by allowing fish reconstruction from cryopreserved somatic cells. Survival rates after nuclear transfer are still low however. The part played by unsuitable handling conditions is often questioned, but the different steps in the procedure are difficult to address separately. In this work led on goldfish (Carassius auratus), the step of somatic cells injection was explored. Non-enucleated metaphase II oocytes were used as a template to explore the toxicity of the injection medium, to estimate the best location where the cell should be injected, and to assess the delay necessary between cell injection and oocyte activation., Results: Trout coelomic fluid was the most suitable medium to maintain freshly spawned oocytes at the metaphase II stage during oocyte manipulation. Oocytes were then injected with several media to test their toxicity on embryo development after fertilization. Trout coelomic fluid was the least toxic medium after injection, and the smallest injected volume (10 pL) allowed the same hatching rates as the non injected controls (84.8% +/- 23). In somatic cell transfer experiments using non enucleated metaphase II oocytes as recipient, cell plasma membrane was ruptured within one minute after injection. Cell injection at the top of the animal pole in the oocyte allowed higher development rates than cell injection deeper within the oocyte (respectively 59% and 23% at mid-blastula stage). Embryo development rates were also higher when oocyte activation was delayed for 30 min after cell injection than when activation was induced without delay (respectively 72% and 48% at mid-blastula stage)., Conclusions: The best ability of goldfish oocytes to sustain embryo development was obtained when the carrier medium was trout coelomic fluid, when the cell was injected close to the animal pole, and when oocyte activation was induced 30 min after somatic cell injection. Although the experiments were not designed to produce characterized clones, application of these parameters to somatic cell nuclear transfer experiments in enucleated metaphase II oocytes is expected to improve the quality of the reconstructed embryos.

In order to determine how soya-bean proteins are digested and metabolized in the human intestine before colonic bacterial fermentation and to estimate their true digestibility, the gastro-jejunal behaviour of soya-bean proteins in water and in two other forms (a concentrated soya-bean-protein solution (isolate) and a drink composed of crude soya-bean proteins (soymilk)) was studied in humans. Experiments were carried out in eight healthy volunteers using a double-lumen steady-state intestinal perfusion method with polyethyleneglycol (PEG) as a non-absorbable volume marker. Gastric emptying and N and electrolyte contents of the jejunal digesta were analysed. Gastric half-emptying time (min) of the liquid phase after water ingestion (12.59 (SE 0.12)) was shorter (P < 0.05) than those for soymilk (37.74 (SE 11.57)) and isolate (36.52 (SE 11.23)). Electrolytic balances showed that for all meals, Na+, Cl- and K+ were secreted when Ca2+ was efficiently absorbed from the jejunal lumen. Gastro-jejunal N absorption for isolate and soymilk were 63 and 49% respectively, and were not significantly different from one another; after water ingestion, endogenous N was estimated to be 21 mmol. An estimate of the exogenous:endogenous values for the effluents was obtained from the amino acid compositions of soymilk and effluents after water or soymilk ingestion, indicating that 70% of the total N was exogenous and 30% endogenous. Under these conditions the endogenous fraction represented 31 mmol after soymilk ingestion and the gastro-jejunal N balance indicated that 54% of the soymilk was absorbed. This finding indicates that the true gastrojejunal digestibility of soya-bean proteins is similar to that of milk proteins.

In rainbow trout (Salmo gairdnerii) lipoprotein profiles change during the annual sexual cycle. Among other factors, lipoprotein lipase (LPL) activity might play a role. This enzyme is activated by trout serum suggesting the existence of a cofactor corresponding to apoprotein CII in this species. In the present study, we determined more accurately some characteristics of the enzyme activity inhibited by 0.3 M NaCl. Trout serum and high density lipoproteins (HDL) activated both rat and trout adipose tissue LPLs. A fraction of apo HDL obtained by gel filtration also activated the enzyme. The mean Mr was 10,000. Isoelectric focusing of the same fraction gave several bands of proteins with apparent pI in the range of 4.2-4.9. These results show that in trout, LPL is activated by a cofactor similar to that in mammals, the apo CII. In addition, a fraction mainly containing apo AI (+ traces of apo C) activated trout LPL and reinforced the activation by apo CII. These findings suggest that trout apo AI may promote the activating effect of apo CII on trout LPL.