Publications by authors named "Riek M"

Recently, serious infections related to the use of tofacitinib (TOF) for treatment of rheumatoid arthritis (RA) have raised considerable interest. This study aimed to compare the risk for serious infections in patients with RA upon receiving TOF versus biologic disease-modifying antirheumatic drugs (bDMARDs) by age at treatment initiation. We identified adult RA patients exposed to TOF or bDMARDs using data collected by the Swiss registry for inflammatory rheumatic diseases (SCQM) from 2015 to 2018.

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Article Synopsis
  • Patients with inflammatory rheumatic diseases (IRD) are at greater risk of severe COVID-19 outcomes, prompting the need to evaluate the effectiveness of mRNA vaccines and treatments in this group.
  • A study compared the antibody responses of IRD patients who received two doses of BNT162b2 and mRNA-1273 vaccines, analyzing samples at various intervals after vaccination.
  • Results showed that mRNA-1273 led to significantly higher antibody levels compared to BNT162b2, particularly benefiting elderly patients, and specific medications lowered antibody responses.
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In order to stabilize a 10-P-3 species with symmetry and two lone pairs on the central phosphorus atom, a specialized ligand is required. Using an NCN pincer, previous efforts to enforce this planarized geometry at P resulted in the formation of a -symmetric, 10π-electron benzazaphosphole that existed as a dynamic "bell-clapper" in solution. Here, OCO pincers 1 and 2 were synthesized, operating under the hypothesis that the more electron-withdrawing oxygen donors would better stabilize the 3-center, 4-electron O-P-O bond of the 10-P-3 target and the sp-hybridized benzylic carbon atoms would prevent the formation of aromatic P-heterocycles.

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Objectives: To examine the effectiveness of tocilizumab (TCZ) with and without synthetic disease-modifying antirheumatic drugs (sDMARDs) in a large observational study.

Methods: Patients with rheumatoid arthritis treated with TCZ who had a baseline visit and information on concomitant sDMARDs were included. According to baseline data, patients were considered as taking TCZ as monotherapy or combination with sDMARDs.

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Objectives: To determine the frequency of use of biologic DMARDs (bDMARDs) in monotherapy, to describe the baseline characteristics of patients treated with bDMARDs in monotherapy and to compare the effectiveness of bDMARDs in monotherapy with that of bDMARDs in combination with synthetic DMARDs (sDMARDs).

Methods: Using data from the Swiss RA (SCQM-RA) registry, bDMARD treatment courses (TCs) were classified either as monotherapy or as combination therapy, depending on the presence of concomitant sDMARDs. Prescription of bDMARD monotherapy was analysed using logistic regression.

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Objectives: To investigate the impact of smoking on the response to treatment with a first tumour necrosis factor inhibitor (TNFi) in patients with axial spondyloarthritis (axSpA) in a real-life cohort.

Methods: Patients fulfilling the Assessment of SpondyloArthritis international Society (ASAS) classification criteria for axSpA in the Swiss Clinical Quality Management Cohort were included in this study. The potential association between smoking status and differential response to TNFi in terms of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Ankylosing Spondylitis Disease Activity Score (ASDAS) was analysed using multiple adjusted longitudinal mixed effect models.

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Objectives: The objective of this evaluation study is to assess a web-based application, currently available on iPad, to document questionnaires regarding patient reported outcomes such as quality of life. Based on the single source approach, the results of these questionnaires are available in the electronic health record to be used for treatment and research purposes. The assessment focuses on the usability and efficiency of the system.

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Background: Documenting quality of life (QoL) in routine medical care and using it both for treatment and for clinical research is not common, although such information is absolutely valuable for physicians and patients alike. We therefore aimed at developing an efficient method to integrate quality of life information into the clinical information system (CIS) and thus make it available for clinical care and secondary use.

Methods: We piloted our method in three different medical departments, using five different QoL questionnaires.

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Background: Saquinavir and ritonavir, both human immunodeficiency virus-1 protease inhibitors, also inhibit the adenosine triphosphate-dependent efflux pump P-glycoprotein (P-gp), which is located at a variety of anatomic sites, including the human intestine. P-gp plays an important role in the absorption, distribution and elimination of numerous drugs. This study investigated the inhibitory potential of multiple administrations of ritonavir-boosted saquinavir at the target therapeutic dose of 1,000 mg saquinavir/100 mg ritonavir twice daily on the pharmacokinetics of oral digoxin, a model P-gp substrate that is predominantly excreted as unchanged drug in the urine.

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Study Objective: To investigate the inhibitory potential of multiple doses of ritonavir-boosted saquinavir on the pharmacokinetics of oral midazolam, a cytochrome P450 (CYP) 3A4 model substrate.

Design: Prospective, open-label, one-sequence, two-period crossover study.

Setting: Clinical pharmacology unit in the United Kingdom.

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This study was performed to determine the effect of two protease inhibitors, saquinavir (SQV, oral 1000 mg bid) boosted by ritonavir (RTV, oral 100 mg bid), on pharmacokinetics (PK) of methadone in opiate-dependent HIV-negative patients on stable methadone maintenance therapy. This was a two-center, open-label, one-sequence cross-over, multiple-dose study in 13 HIV-negative patients who were on stable methadone therapy (oral, 60-120 mg qd). All patients continued methadone treatment on days 2-15.

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OBJECTIVE: This study was designed to investigate the pharmacokinetic effects of coadministration of saquinavir/ritonavir with efavirenz at steady state. METHODS: Healthy volunteers in this open-label, two-arm, one-sequence, two-period crossover study (planned enrollment of 40 participants) were randomized to one of two treatment arms: those in Arm 1 were scheduled to receive saquinavir/ritonavir 1,000/100 mg orally twice daily for 29 days and efavirenz 600 mg orally once daily starting on day 15 and continuing through day 29; participants randomized to Arm 2 were to receive efavirenz once daily for 29 days and saquinavir/ritonavir 1,000/100 mg twice daily starting on day 15 through day 29. Assessments included vital signs, laboratory analyses, electrocardiography, and blood levels of total saquinavir, ritonavir, and efavirenz.

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OBJECTIVES: Rifampin is a potent inducer of the cytochrome P450 3A4 isoenzyme (CYP3A4) that metabolizes most protease inhibitor (PI) antiretrovirals. This study was designed to evaluate the steady-state pharmacokinetics and tolerability of the coadministration of the PIs saquinavir and ritonavir (a CYP3A4 inhibitor used as a pharmacoenhancer of other PIs) and rifampin when coadministered in healthy HIV-negative volunteers. METHODS: In an open-label, randomized, one sequence, two-period crossover study involving 28 healthy HIV-negative volunteers, arm 1 was randomized to receive saquinavir/ritonavir 1000/100 mg twice daily while arm 2 received rifampin 600 mg once daily for 14 days.

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The effects of food on the pharmacokinetics of erlotinib were investigated in two open-label, randomized studies. In a single-dose crossover study (n = 18), 150 mg of erlotinib was administered under either fasting or fed conditions. In the first period, an approximate doubling in the area under the plasma concentration-time curve was evidenced by the geometric mean ratio (GMR) of 2.

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Background: Erlotinib is an orally active antitumor agent. Analyses in vitro using human liver microsomes and recombinant enzymes showed that erlotinib was metabolized primarily by CYP3A4, with a secondary contribution from CYP1A2.

Methods: A computer-based simulation model, SimCYP, predicted that CYP3A4 contributed to approximately 70% of the metabolic elimination of erlotinib, with CYP1A2 being responsible for the other approximately 30%.

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The genetic structure of metapopulations offers insights into the genetic consequences of local extinction and recolonization. We studied allozyme variation in rock pool metapopulations of two species of waterfleas (Daphnia) with the aim to understand how these dynamics influence genetic differentiation. We screened 138 populations of D.

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Objective: To establish the bioequivalence of a 500 mg film-coated tablet of saquinavir mesylate (FCT SQV) to the 200 mg hard-capsule saquinavir mesylate (HC SQV), both boosted with ritonavir and administered under fed conditions.

Methods: We carried out a multi-centre, open-label, randomized, two-sequence, four-period, two-treatment, replicated crossover study in 93 healthy men and 7 healthy women. Individuals were randomly assigned to receive sequential single doses of saquinavir in one of two treatment sequences: ABAB or BABA.

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If colonization of empty habitat patches causes genetic bottlenecks, freshly founded, young populations should be genetically less diverse than older ones that may have experienced successive rounds of immigration. This can be studied in metapopulations with subpopulations of known age. We studied allozyme variation in metapopulations of two species of water fleas (Daphnia) in the skerry archipelago of southern Finland.

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The deleterious effects of inbreeding have long been known, and inbreeding can increase the risk of extinction for local populations in metapopulations. However, other consequences of inbreeding in metapopulations are still not well understood. Here we show the presence of strong inbreeding depression in a rockpool metapopulation of the planktonic freshwater crustacean Daphnia magna, which reproduces by cyclical parthenogenesis.

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Immigrants to habitats occupied by conspecific organisms are usually expected to be competitively inferior, because residents may be locally adapted. If residents are inbred, however, mating between immigrants and residents results in offspring that may enjoy a fitness advantage from hybrid vigor. We demonstrate this effect experimentally in a natural Daphnia metapopulation in which genetic bottlenecks and local inbreeding are common.

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The consequences of group-keeping as a social stressor on the solitary-living golden hamster were studied. Two females at the same stage of the estrous cycle were kept together for 5 weeks. Behavioral observations showed that the dominance structures within groups were unstable.

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We have considered the extracellular serine protease thrombin and its receptor as endogenous mediators of neuronal protection against brain ischemia. Exposure of gerbils to prior mild ischemic insults, here two relatively short-lasting occlusions (2 min) of both common carotid arteries applied at 1-day intervals 2 days before a severe occlusion (6 min), caused a robust ischemic tolerance of hippocampal CA1 neurons. This resistance was impaired if the specific thrombin inhibitor hirudin was injected intracerebroventricularly before each short-lasting insult.

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