Pattern of carbon dioxide production and retention is similar in adult pigs when fed hourly,but not when fed a single meal

Background

The understanding of bicarbonate kinetics and CO₂ retention in the body is necessary to conduct amino acid tracer oxidation studies in both humans and laboratory animals. Significant metabolic activity is associated with eating which can affect bicarbonate steady state kinetics. A study was conducted to assess the impact of feeding regimen on the recovery of labelled bicarbonate and energy expenditure in adult female pigs (sows). Five catheterized sows (235 ± 5 kg) were fed semi-synthetic diets as: a single meal 2 h into the infusion after an overnight fast, or in eight hourly meals starting 2 h before the infusion. Oxygen consumption, CO₂ production and ¹⁴CO₂ recovery (ie fraction not retained) were determined during primed, constant intravenous infusions of NaH¹⁴CO₃.

Results

The ¹⁴CO₂ recovery (%) after fasting (58.1 ± 4.8) was lower than that after single meal feeding (78.8 ± 5.9) or hourly meal feeding (81.0 ± 2.6, P = 0.03). CO₂ production correlated with ¹⁴CO₂ recovery during hourly feeding (r = 0.40, P = 0.01); this relationship was not significant after single meal feeding (P = 0.30), probably due to physical activity-associated CO₂ production.

Conclusions

The correlation of CO₂ retention factors with CO₂ production during hourly feeding suggests that this regimen should be preferred for future amino acid kinetics studies.

     

Multimodal data acquisition at SARS-CoV-2 drive through screening centers: Setup description and experiences in Saarland,Germany

SARS-CoV-2 drive through screening centers (DTSC) have been implemented worldwide as a fast and secure way of mass screening. We use DTSCs as a platform for the acquisition of multimodal datasets that are needed for the development of remote screening methods. Our acquisition setup consists of an array of thermal, infrared and RGB cameras as well as microphones and we apply methods from computer vision and computer audition for the contactless estimation of physiological parameters. We have recorded a multimodal dataset of DTSC participants in Germany for the development of remote screening methods and symptom identification. Acquisition in the early stages of a pandemic and in regions with high infection rates can facilitate and speed up the identification of infection specific symptoms and large-scale data acquisition at DTSC is possible without disturbing the flow of operation.     

On a basic 31 kDa muscle membrane protein in cattle and pig, presumably equivalent to the class II antigen associated p31 molecule

In a recent paper we gave evidence by two-dimensional electrophoresis that, in man, the class II antigen associated glycoprotein p31 (also called Ii, In, M1, DRγ, XMl) is expressed not only in the membranes of B lymphocytes but also in those of muscle, liver and brain. It can therefore be assumed that the p31 is not really associated with the human class II antigens but is a ubiquitous molecule.
Here we demonstrate for the first time that the muscle membranes of cattle and pig contain corresponding polypeptides, with a molecular weight of about 31 kDa and an isoelectric point around 7.5, which comigrate in two-dimensional electrophoresis with p31 derived from the human muscle. Thus, in cattle and pig too, these proteins seem to be equivalent to the class II antigen associated p31, showing a tissue distribution wider than observed up to now. The molecules can be concentrated by ion-exchange chromatography.     

New protein polymorphisms in cattle

Preparation techniques are outlined for blood samples from cattle, which permit rapid separation of several constant fractions within a large number of animals. Electrophoretical examination of the blood fractions, the methods for which are described, rendered possible the phenotyping of 5 new polymorphic protein systems. Furthermore the electrophoresis of erythrocyte carboanhydrase was tested.
In about 550 cattle, including familial material of the breed 'Deutsche Schwarz-bunte', the observed phenotypes, segregation data and allele frequencies of 7 polymorphisms, are described. We were able to find new polymorphisms of serum post-transferrins (Ptf), leucocytic proteins 1 and 2 (Leu₁ and Leu₂), and erythrocytic proteins 1 and 2 (Ery₁, and Ery₂). Moreover, data of carbonic anhydrase isoenzymes stained with protein dyes, as well as identified as esterases, are given.