Publications by authors named "Christopher C Calvert"

Article Synopsis
  • This study investigated the bioavailability of vitamin B-12 from chicken eggs that were enriched with a carbon-12 labeled version of B12 (C-B12), using accelerator mass spectrometry (AMS) instead of traditional radioactive methods.
  • Ten human volunteers consumed cooked eggs containing C-B12, and researchers measured its absorption through blood, urine, and stool samples over one week, finding that bioavailability ranged from 13.2% to 57.7% with an average of 30.2%.
  • The eggs provided around 1.4 to 2.6 μg of B12 per serving, confirming that eggs are a good source of this vitamin, contributing roughly 20% of the recommended daily allowance for adults
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Scope: This work aims to evaluate changes in the fecal metabolomic profile due to grape seed extract (GSE) intake by untargeted and targeted analysis using high resolution mass spectrometry in conjunction with multivariate statistics.

Methods And Results: An intervention study with six crossbred female pigs was performed. The pigs followed a standard diet for 3 days, then they were fed with a supplemented diet containing 1% (w/w) of MegaNatural® Gold grape seed extract for 6 days.

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Proanthocyanidin (PAC) consumption has been linked to better colonic health, but PACs are poorly absorbed, making them a target for colonic metabolism. The resulting metabolites are low molecular weight and could potentially be absorbed. To understand the effects of dietary PACs it would be important to resolve the metabolic issue and link these changes to microbial population changes in a suitable model for human digestion.

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The influence of dietary restriction on the negative feedback potency of 17-beta-estradiol (E2) was evaluated in both castrated male (wethers) and female sheep (OVX ewes) during the breeding season. In study 1, OVX ewes received maintenance or restricted dietary energy for 7 weeks or maintenance energy for 6 weeks prior to a 5 day fast (n=12ewes/feeding group). Estradiol (0.

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Gonadectomy predisposes domestic cats to undesired body weight gain and obesity. The disturbance responsible for this disregulation of energy balance has not been clearly identified. Energy intake and expenditure, body composition and plasma concentrations of leptin, insulin, glucose and triacylglycerol were determined during a 36-wk period in adult male (2-5 y) gonadectomized (n = 8) and intact (n = 8) normal cats and gonadectomized (n = 8) and intact (n = 8) lipoprotein lipase (LPL)-deficient cats.

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Synopsis of recent research by authors named "Christopher C Calvert"

  • Christopher C Calvert focuses on the bioavailability and metabolic effects of nutrients, particularly vitamin B-12 and proanthocyanidins from grape seeds, utilizing advanced techniques such as accelerator mass spectrometry and high-resolution mass spectrometry.
  • His research has revealed significant findings regarding the absorption and health impacts of these compounds on human and animal models, notably demonstrating how endogenous labeling can optimize the study of nutrient bioavailability.
  • Additionally, Calvert's work addresses the implications of diet on metabolic profiles and health outcomes, including alterations in gut microbiota and hormonal responses under conditions of dietary restriction, particularly in relation to weight management in pets.

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