Publications by authors named "Birgit Reiter"

Background: Isotope tracing experiments in cellular metabolomics are challenged by the multiple isomers and in-source fragments, which need to be considered to obtain unbiased isotopologue ratio measurements. Thus, both, selectivity and sensitivity are key requirements for customized workflows. Trapped ion mobility spectrometry (TIMS) introduces an additional separation dimension to mass spectrometry, separating otherwise co-eluting isomers by measuring the ion mobility of a molecule.

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Objectives: This study measured the penetration of ceftaroline and ceftazidime/avibactam into cerebrospinal fluid (CSF) to evaluate the potential of both drugs for treatment of central nervous system (CNS) infections.

Methods: In this prospective, single-centre pharmacokinetic (PK) study, 24 healthy volunteers equally divided into two groups received four doses of either 600 mg ceftaroline fosamil or 2000/500 mg ceftazidime/avibactam as intravenous infusions over 2 h at 8 h intervals for 4 doses. Plasma samples were obtained on both study days and CSF was sampled once per subject at either 2 h, 4 h or 8 h after the start of the last infusion via lumbar puncture.

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Objective: Metabolomics measurements of eccrine sweat may provide novel and relevant biomedical information to support predictive, preventive and personalised medicine (3PM). However, only limited data is available regarding metabolic alterations accompanying chemotherapy of breast cancer patients related to residual cancer burden (RCB) or therapy response. Here, we have applied Metabo-Tip, a non-invasive metabolomics assay based on the analysis of eccrine sweat from the fingertips, to investigate the feasibility of such an approach, especially with respect to drug monitoring, assessing lifestyle parameters and stratification of breast cancer patients.

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Introduction: Hemodialysis patients (HDPs) exhibit extensive cardiovascular risk. The widely prescribed anti-platelet agent clopidogrel is metabolically activated by cytochrome enzymes, which may be impaired by uremia and chronic low-grade inflammation, typically present in HDPs. We conducted a prospective multicenter study to investigate the pharmacokinetics and pharmacodynamics of clopidogrel in HDPs and healthy volunteers (HVs).

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Article Synopsis
  • Clomipramine (CLOMI) is effective for premature ejaculation but may cause erectile dysfunction, while yohimbine (YOH) helps with erectile dysfunction and could boost libido; combining both drugs may harness their benefits.
  • In a study with 15 healthy male subjects, researchers analyzed how these drugs interact when taken together, assessing their pharmacokinetics and safety profiles through various plasma sampling methods.
  • Results indicated a significant interaction with YOH when combined with CLOMI, suggesting competitive inhibition of YOH metabolism by CLOMI, but this interaction is considered minor according to regulatory guidelines, which supports further studies on their combined efficacy.
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Background: Obesity in pregnancy is linked to adverse clinical outcomes such as gestational diabetes. Recently, a risk score calculated by different ceramide concentrations was recognized as a new way to investigate cardiovascular risk. The aim was to analyze if the ceramide risk score and cardiometabolic risk vary between normal-weight, obese, and females with prior Roux-en-Y bypass surgery (RYGB) during pregnancy.

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Background: Invasive aspergillosis is a severe fungal infection that affects multiple organ systems including the CNS and the lungs. Isavuconazole, a novel triazole antifungal agent, has demonstrated promising activity against Aspergillus spp. However, data on the penetration of isavuconazole into the CNS and ELF and intracellular accumulation remain limited.

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Objective: To test whether recombinant human diamine oxidase (rhDAO) with a mutated heparin-binding motif (mHBM), which shows an increased alpha-distribution half-life, prevents histamine-induced hemodynamic effects.

Material: Thirty-eight female guinea pigs were either pretreated with rhDOA_mHBM or buffer.

Treatment And Methods: Guinea pigs received a continuous infusion of histamine.

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Background: A drug-drug interaction (DDI) may occur when transitioning from intravenous P2Y inhibition with cangrelor to oral P2Y inhibition with prasugrel. However, this has never been tested in patients undergoing percutaneous coronary intervention (PCI).

Objectives: This study sought to rule out a DDI when cangrelor and prasugrel are concomitantly administered in PCI patients.

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Objectives: Peritonitis is a serious complication in patients undergoing automated peritoneal dialysis (APD) that increases morbidity and frequently disqualifies patients from the peritoneal dialysis programme. Ceftazidime/avibactam (CAZ/AVI) is a potential treatment option for APD patients with peritonitis caused by resistant Gram-negative bacteria, but limited data exist on systemic and target-site pharmacokinetics (PK) in patients undergoing APD. This study set out to investigate the PK of CAZ/AVI in plasma and peritoneal dialysate (PDS) of patients undergoing APD.

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Background: Combining mouse experiments with big data analysis of the Austrian population, we investigated the association between high-dose statin treatment and bone quality.

Methods: The bone microarchitecture of the femur and vertebral body L4 was measured in male and ovariectomized female mice on a high-fat diet containing simvastatin (1.2 g/kg).

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To investigate long COVID-19 syndrome (LCS) pathophysiology, we performed an exploratory study with blood plasma derived from three groups: 1) healthy vaccinated individuals without SARS-CoV-2 exposure; 2) asymptomatic recovered patients at least three months after SARS-CoV-2 infection and; 3) symptomatic patients at least 3 months after SARS-CoV-2 infection with chronic fatigue syndrome or similar symptoms, here designated as patients with long COVID-19 syndrome (LCS). Multiplex cytokine profiling indicated slightly elevated pro-inflammatory cytokine levels in recovered individuals in contrast to patients with LCS. Plasma proteomics demonstrated low levels of acute phase proteins and macrophage-derived secreted proteins in LCS.

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Background: There are no studies specifically designed to rule out a drug-drug interaction (DDI) when cangrelor is used among patients who have been pretreated with ticagrelor.

Objectives: This study sought to rule out a DDI among cangrelor-treated patients who have been pretreated with ticagrelor.

Methods: In this prospective, randomized, double-blind, placebo-controlled, crossover, pharmacokinetic (PK) and pharmacodynamic (PD) study, patients with coronary artery disease (N = 20) were pretreated with a 180-mg ticagrelor loading dose and after 1 hour randomized to placebo or cangrelor (bolus and infusion for 2 hours).

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Objectives: The efficacy and quality of generic antibacterial drug formulations are often questioned by both healthcare specialists and patients. Therefore, the present study investigated the interchangeability of generic drugs with their originators by comparing bioequivalence parameters and stability data of generic cefepime, linezolid and piperacillin/tazobactam with their respective originator drugs.

Methods: In this open-label, randomized, crossover bioequivalence study, three groups of 12 healthy volunteers each received a single intravenous infusion of either 2 g of cefepime or 4.

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Background And Objective: In microdose studies, drug pharmacokinetics is measured in humans after administration of subtherapeutic doses. While previous microdose studies focused primarily on plasma pharmacokinetics, we set out to evaluate the feasibility of microdosing for a pharmacokinetic assessment in subcutaneous tissue and epithelial lining fluid.

Methods: Healthy subjects received a single intravenous bolus injection of a microdose of [C]ciprofloxacin (1.

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Objective: Targeted temperature management (TTM) is part of standard post-resuscitation care. TTM may downregulate cytochrome enzyme activity and thus impact drug metabolism. This study compared the pharmacokinetics (PK) of pantoprazole, a probe drug of CYP2C19-dependent metabolism, at different stages of TTM following cardiac arrest.

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Targeting interleukin-6 (IL-6) is a promising strategy to counteract antibody-mediated rejection (ABMR). In inflammatory states, IL-6 antagonism was shown to modulate cytochrome P450 (CYP), but its impact on drug metabolism in ABMR treatment was not addressed so far. We report a sub-study of a phase 2 trial of anti-IL-6 antibody clazakizumab in late ABMR (ClinicalTrials.

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Ketamine is a powerful glutamatergic long-lasting antidepressant, efficient in intractable major depression. Whereas ketamine's immediate psychomimetic side-effects were linked to glutamate changes, proton MRS (H-MRS) showed an association between the ratio of glutamate and glutamine and delayed antidepressant effect emerging ∼2 h after ketamine administration. While most H-MRS studies focused on anterior cingulate, recent functional MRI connectivity studies revealed an association between ketamine's antidepressant effect and disturbed connectivity patterns to the posterior cingulate cortex (PCC), and related PCC dysfunction to rumination and memory impairment involved in depressive pathophysiology.

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Introduction: Converging evidence suggests that ketamine elicits antidepressant effects enhanced neuroplasticity precipitated by a surge of glutamate and modulation of GABA. Magnetic resonance spectroscopic imaging (MRSI) illustrates changes to cerebral glutamate and GABA immediately following ketamine administration during dissociation. However, few studies assess subacute changes in the first hours following application, when ketamine's antidepressant effects emerge.

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Background: Cannabis has increasingly been used for medical and recreational purposes. The main pharmacological compound in cannabis is tetrahydrocannabinol (THC), which has sedative, anxiolytic and analgesic effects. In some animal models, THC has also been shown to reduce the minimum alveolar concentration (MAC) of halothane and cyclopropane, but its effect on sevoflurane, currently the most commonly used inhalational anaesthetic agent, has not been investigated.

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Background: Acidic pH has been shown to impact the antibiotic activity of non-β-lactams in urine.

Objectives: To investigate the in vitro activity of ceftolozane/tazobactam compared with meropenem at different pH settings in urine.

Methods: We determined the MICs for 30 clinical isolates of Escherichia coli, 25 clinical isolates of Klebsiella pneumoniae and 24 clinical isolates of Proteus mirabilis in pooled human urine and standard growth medium at pH 5 and 7.

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In vitro pharmacodynamic models are used to optimize in vivo dosing regimens in antimicrobial drug development. One limiting factor of such models is the lack of host factors such as corpuscular blood components as erythrocytes which have already been shown to impact activity of antibiotics and/or growth of the pathogen. However, the impact of thrombocytes has not previously been investigated.

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Article Synopsis
  • New-onset diabetes often improves after pancreaticoduodenectomy (PD), possibly due to increased production of glucagon-like peptide-1 (GLP-1) caused by changes in digestion.
  • The study involved comparing GLP-1 release in 15 patients who had a Whipple procedure versus 15 who had pylorus-preserving surgery, measuring various blood markers after a test meal.
  • Results showed that faster gastric emptying and the type of surgery were linked to higher GLP-1 levels, and patients with Whipple surgery had better blood sugar control compared to those with pylorus preservation.
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It has been shown that protein binding, temperature, and pH influence in vitro pharmacodynamic (PD) models. The fact that corpuscular blood compounds might also have an important impact is something which has, until now, often been neglected. We investigated if the addition of human erythrocytes to standard growth media (Mueller Hinton Broth, MHBII) has an influence on bacterial growth behavior and on antibiotic efficacy.

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Human milk oligosaccharides (HMOs) are bioactive glycans linked with health benefits to both the breast-fed infant and lactating mother. We hypothesized that HMOs are present before lactation, already during pregnancy, and are influenced by maternal body composition. In a pilot study, we investigated individual and temporal variations in HMO composition and concentration in maternal serum at gestational weeks 10-14 ( visit 1), 20-24 ( visit 2), and 30-35 (visit 3) (V1, V2, and V3, respectively) and associations with maternal body composition.

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