Publications by authors named "C Knapp"

The experiments presented here are based on the reconfiguration of an ancient medicine, Lemnian Earth (LE) (terra sigillata, stamped earth, sphragis), an acclaimed therapeutic clay with a 2500-year history of use. Based on our hypothesis that LE was not a natural material but an artificially modified one involving a clay-fungus interaction, we present results from experiments involving the co-culture of a common fungus, Penicillium purpurogenum (Pp), with two separate clay slurries, smectite and kaolin, which are the principal constituents of LE. Our results show: (a) the leachate of the Pp+smectite co-culture is antibacterial in vitro, inhibiting the growth of both Gram-positive and Gram-negative bacteria; (b) in vivo, supplementation of regular mouse diet with leachates of Pp+smectite increases intestinal microbial diversity; (c) Pp+kaolin does not produce similar results; (d) untargeted metabolomics and analysis of bacterial functional pathways indicates that the Pp+smectite-induced microbiome amplifies production of short-chain fatty acids (SCFAs) and amino acid biosynthesis, known to modulate intestinal and systemic inflammation.

View Article and Find Full Text PDF

Rationale: Psychostimulants, such as amphetamine (AMPH) and methylphenidate (MPH), non-selectively elevate extracellular concentrations of the catecholamine neurotransmitters, dopamine (DA) and norepinephrine (NE), and are common pharmacological strategies used to improve prefrontal cortex (PFC)-dependent cognitive dysfunction. However, this approach can be problematic given AMPH has been shown to increase preference for risky choices in a rodent assay of risk/reward decision making. SK609 is a novel NE reuptake blocker that selectively activates DA D3 receptors without affinity for the DA transporter.

View Article and Find Full Text PDF

Background: The prevalence of depression is high in the chronic kidney disease (CKD) (20-40%) and dialysis (30-50%) populations. Less is known about how depressive symptoms change over time in patients with CKD.

Methods: Participants in the Brain in Kidney Disease (BRINK) cohort study completed a depressive symptom questionnaire (PHQ-9) and serum creatinine testing annually.

View Article and Find Full Text PDF
Article Synopsis
  • Researchers found that carbon dioxide can be inserted into a silicon-nitrogen bond of a specific chemical compound (N-heterocyclic iminosilane) in a way that can be reversed.
  • Tests in liquid conditions showed that this insertion process doesn't release or absorb heat, making it thermoneutral, and can go back to its original state.
  • In solid form, the carbon dioxide can be stored for a long time, but it only gets released when heated to 133°C.
View Article and Find Full Text PDF
Article Synopsis
  • SNARE-mediated membrane fusion is influenced by the lipid composition of bilayers, affecting how proteins interact with lipids and the membranes' physical properties, like curvature.
  • Research on yeast vacuole fusion revealed that certain lysophospholipids, specifically lysophosphatidylcholine (LPC), can inhibit fusion based on their acyl chain length and saturation.
  • The study also showed that head group size is crucial in blocking fusion, with different lysolipids having varying effects on calcium transport and vacuole acidification.
View Article and Find Full Text PDF