Effect of Ketoconazole and Rifampicin on the Pharmacokinetics of Ranitidine in Healthy Human Volunteers: A Possible Role of P-Glycoprotein

AbstractThe role of triglycerides carried in the triglyceride-rich lipoproteins (TRL) in the progression of atherosclerosis is uncertain. Identification of oxidized triglycerides and its possible association with atherosclerosis were largely ignored. Here we applied mass spectrometric approach to detect and identify triglyceride hydroperoxides (TGOOH) in human plasma and lipoproteins.EDTA plasma was collected from healthy human volunteers (n=9) after 14–16 h of fasting. Very low-density lipoprotein (VLDL)We identified 11 molecular species of TGOOH in either plasma or VLDL and IDL, of which TGOOH-18:1/18:2/16:0, TGOOH-18:1/18:1/16:0, TGOOH-16:0/18:2/16:0, TGOOH-18:1/18:1/18:1, and TGOOH-16:0/20:4/16:0 were most dominant. These TGOOH molecules are carried by TRL but not by LDL and HDL. Mean concentration of TGOOH in plasma, VLDL and IDL were, respectively, 56.1±25.6, 349.8±253.6 and 512.5±173.2 μmol/mol of triglycerides.This is the first report to identify several molecular species of oxidized triglycerides in TRL. Presence of oxidized triglyceride may contribute to the atherogenicity of TRL. Further work is needed to elucidate the association of the oxidized triglyceride in atherosclerosis.

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Role of prebiotics and probiotics in oral health

Nutrition & Food Science ◽

10.1108/nfs-03-2017-0056 ◽

2018 ◽

Vol 48 (1) ◽

pp. 16-29 ◽

Cited By ~ 2

Author(s):

Richard Frank Tester ◽

Farage H. Al-Ghazzewi

Keyword(s):

Oral Care ◽

The Body ◽

In Vivo Studies ◽

Gut Health ◽

Healthy Human ◽

Content Type ◽

Human Volunteers ◽

Health Related

Purpose This paper aims to focus on the utilisation of pre- and probiotics for oral care and the state of knowledge at this time. Design/methodology/approach Pre- and probiotics describe beneficial carbohydrates and microbiota, respectively, for optimal gut health. Carbohydrates provide energy selectively for the gut-friendly bacteria. The use of both carbohydrates and bacteria is, however, being expanded into other areas of the body – including the skin, vagina and oral cavity – for health-related applications. Findings There is increased interest in both pre- and probiotics for oral care products. The importance of oral microflora and their selective substrates is discussed against a background of contemporary oral care approaches. The issues and benefits are discussed in this review. Originality/value It is clear that consumption of prebiotics and probiotics may play a role as potential prophylactic or therapeutic agents for reducing the presence of organisms in the mouth associated with tooth decay. To confirm a beneficial effect of pre- and probiotics further in vivo studies involving healthy human volunteers should be considered.

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Risk-Promoting Effects of Reward-Paired Cues in Human Sign- and Goal-Trackers

10.31234/osf.io/rxbpw ◽

2021 ◽

Author(s):

Mariya Cherkasova ◽

Eve Limbrick-Oldfield ◽

Luke Clark ◽

Jason J. S. Barton ◽

A. Jon Stoessl ◽

...

Keyword(s):

Eye Gaze ◽

Cost Benefit ◽

Incentive Salience ◽

Healthy Human ◽

Sign Tracking ◽

Reward Delivery ◽

Human Volunteers ◽

Within Subjects ◽

Goal Tracking

The incentive sensitization theory of addiction proposes that through repeated associations with addictive rewards, addiction-related stimuli acquire a disproportionately powerful motivational pull on behaviour. Animal research suggests trait-like individual variation in the degree of incentive salience attribution to reward-predictive cues, defined phenotypically as sign-tracking (high) and goal-tracking (low incentive salience attribution). While these phenotypes have been linked to addiction features in rodents, their translational validity has been little studied. Here, we examined whether sign- and goal-tracking in healthy human volunteers modulates the effects of reward-paired cues on cost-benefit decision making. Sign-tracking was measured in a Pavlovian conditioning paradigm as the amount of eye gaze fixation on the reward-predictive cue versus the location of impending reward delivery. In Study 1 (Cherkasova et al, 2018), participants were randomly assigned to perform a two-choice lottery task in which rewards were either accompanied (cued, n=63) or unaccompanied (uncued, n=68) by money images and casino jingles. In Study 2, participants (n=58) performed cued and uncued versions of the task in a within-subjects design. Across both studies, cues promoted riskier choice, and both studies yielded evidence of goal-tracking being associated with greater risk-promoting effects of cues. These findings are at odds with the notion of sign-trackers being preferentially susceptible to the influence of reward cues on behavior and point to the role of mechanisms besides incentive salience in mediating such influences.

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Pattern of ventilation in young adults

Journal of Applied Physiology ◽

10.1152/jappl.1964.19.2.195 ◽

1964 ◽

Vol 19 (2) ◽

pp. 195-198 ◽

Cited By ~ 149

Author(s):

Henrik H. Bendixen ◽

Gene M. Smith ◽

Jere Mead

Keyword(s):

Average Rate ◽

Respiratory Frequency ◽

Respiratory Cycle ◽

Healthy Human ◽

Inspiratory Phase ◽

Human Volunteers ◽

The Mean ◽

Physiologic Role ◽

Phase Normal

The ventilatory pattern at rest was examined in 28 healthy human volunteers by recording pneumograph tracings for a 1-hr period. The mean respiratory frequency was 19/min in females, 16/min in males, but with considerable variation both within and among subjects. The mean inspiratory phase accounted for one-third of the respiratory cycle, but this fraction increased with increasing respiratory frequency and decreased when the frequency slowed. Tidal volumes varied greatly, and sighing (breaths larger than three times the average tidal volume) occurred at an average rate of 10/hr for females, 9/hr for males. The possible physiologic role of periodic deep breaths, or sighs, in providing reinflation of atelectatic areas is discussed. respiratory cycle at rest; respiratory frequency and tidal volumes; periodic deep breaths (sighing); inspiratory phase as related to expiratory phase; normal breathing; hyperinflation; respiration; rate of respiration; pneumographic tracings Submitted on November 8, 1962

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Effect of silymarin pretreatment on the bioavailability of domperidone in healthy human volunteers

Drug Metabolism and Drug Interactions ◽

10.1515/dmdi-2014-0013 ◽

2014 ◽

Vol 29 (4) ◽

Cited By ~ 4

Author(s):

Shravan Kumar Yamsani ◽

Madhusudan Rao Yamsani

Keyword(s):

Oral Bioavailability ◽

Pharmacokinetic Parameters ◽

Rat Intestine ◽

Healthy Human ◽

P Glycoprotein ◽

Human Volunteers ◽

Significant Difference

AbstractThe aim of this study was to investigate the effect of silymarin pretreatment on domperidone oral bioavailability in humans.The rats were pretreated with silymarin for 7 days. The transport of domperidone across the rat intestine (duodenum, jejunum, ileum, and colon) was studied by usingIn the everted sac and non-everted sac study with silymarin pretreatment, domperidone transport increased from the duodenum, jejunum, ileum, and colon. The silymarin pretreatment increased the bioavailability of domperidone. There was a statistically significant difference in the pharmacokinetic parameters CThe significant difference in absorption of domperidone on pretreatment with silymarin is due to the inhibition of P-glycoprotein and CYP3A. Silymarin, which inhibits CYP3A4, should be contraindicated for domperidone.

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Differential 5-HT3 mediation of human gastrocolonic response and colonic peristaltic reflex

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1998.275.3.g498 ◽

1998 ◽

Vol 275 (3) ◽

pp. G498-G505 ◽

Cited By ~ 9

Author(s):

Einar S. Björnsson ◽

William D. Chey ◽

Uri Ladabaum ◽

Michelle L. Woods ◽

Forrest G. Hooper ◽

...

Keyword(s):

Motor Function ◽

Healthy Human ◽

Double Blind ◽

Peristaltic Reflex ◽

Colonic Motor ◽

Human Volunteers ◽

Gastrocolonic Response ◽

Colonic Distension ◽

Antral Distension

Colonic motor function is modulated by extended and local neural reflexes involving unknown mediators. To test the role of serotonin (5-HT3) pathways, increases in colonic tone during antral distension and duodenal lipid perfusion (gastrocolonic responses) and changes in orad and caudad colonic tone in response to local colonic distension (peristaltic reflex) were measured after double-blind granisetron (10 μg/kg) or placebo infusion in healthy human volunteers. Antral distension evoked increases in colonic tone, which were blunted by granisetron ( P < 0.05) without effects on antral compliance. Intraduodenal lipid perfusion also evoked increased colonic tone, which was reduced by granisetron ( P < 0.05). In contrast, orad colonic contractions and caudad relaxations and contractions during colonic distension were unaffected by granisetron. In conclusion, 5-HT3 receptor antagonism blunts both the mechano- and chemoreceptor components of the human gastrocolonic response without altering antral compliance. In contrast, 5-HT3 pathways play no role in the ascending or descending components of the colonic peristaltic reflex. These findings demonstrate different roles for 5-HT3 receptors in the control of colonic motor function by the proximal gastrointestinal tract and by local neural reflexes.

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