Publications by authors named "Ulrich Klotz"

The use of biodegradable materials for implants is a promising strategy to overcome known long-term clinical complications related to permanent implants. Ideally, biodegradable implants support the damaged tissue for a certain period and then degrade, while the physiological function of the surrounding tissue is restored. Although Mg-based alloys nearly ideally lend themselves to biodegradable implants, a few critical shortcomings promoted the development of alternative alloy systems.

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The pharmacokinetics (PK) of ethanol are important in pharmacology and therapeutics because of potential drug-alcohol interactions as well as in forensic science when alcohol-related crimes are investigated. The PK of ethanol have been extensively studied since the 1930s, although some issues remain unresolved, such as the significance of first-pass metabolism, whether zero-order kinetics apply, and the effects of food on bioavailability. We took advantage of nonlinear mixed-effects modeling to describe blood-alcohol concentration (BAC) profiles derived from 3 published clinical studies involving oral, intraduodenal, and intravenous administration of ethanol with and without food.

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Zinc (Zn) and its alloys are proposed as promising resorbable materials for osteosynthesis implants. Detailed studies should be undertaken to clarify their properties in terms of degradability, biocompatibility and osteoinductivity. Degradation products of Zn alloys might affect directly adjacent cellular and tissue responses.

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Zinc (Zn) and Zn-based alloys have been proposed as a new generation of absorbable metals mainly owing to the moderate degradation behavior of zinc between magnesium and iron. Nonetheless, mechanical strength of pure Zn is relatively poor, making it insufficient for the majority of clinical applications. In this study, a novel Zn-2Ag-1.

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Zinc (Zn) alloys have been considered as promising absorbable metals, mainly due to their moderate degradation rates ranging between magnesium alloys and iron alloys. The degradation behavior depends on the specific physiological environment. Released metallic ions and corrosion products directly influence biocompatibility.

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Zn-based biodegradable metallic materials have been regarded as new potential biomaterials for use as biodegradable implants, mainly because of the ideal degradation rate compared with those of Mg-based alloys and Fe-based alloys. In this study, we developed and investigated a novel Zn-4 wt % Ag alloy as a potential biodegradable metal. A thermomechanical treatment was applied to refine the microstructure and, consequently, to improve the mechanical properties, compared to pure Zn.

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In recent years, the issue of herbal medicine-drug interactions has generated significant concern. Such interactions can increase the risk for an individual patient, especially with regard to drugs with a narrow therapeutic index (e.g.

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Nanoparticles delivery of oligonucleotides represents a potential approach for cancer treatment. However, most of the experiments were based on established cancer cell lines and may not reflect the original solid tumor in vivo. Both, tumor microenvironment and tumor cell biological properties in the tumor can influence the delivery efficiency of oligonucleotides.

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Ageing is characterized by a progressive decline in the functional reserve of multiple organs and systems, which can influence drug disposition. In addition, comorbidity and polypharmacy are highly prevalent in the elderly. As ageing is associated with some reduction in first-pass metabolism, bioavailability of a few drugs can be increased.

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The therapeutic effects and metabolism of mesalazine (5-aminosalicylic acid) in patients with inflammatory bowel disease require intracellular accumulation of the drug in intestinal epithelial cells and hepatocytes. The molecular mechanisms of mesalazine uptake into cells have not been characterized so far. Using human embryonic kidney cells stably expressing uptake transporters of the organic anion-transporting polypeptide (OATP) family, which are expressed in human intestine and/or liver, we found that mesalazine uptake is mediated by OATP1B1, OATP1B3, and OATP2B1 but not by OATP1A2 and OATP4A1.

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A promising approach for treatment of non-small cell lung cancer (NSCLC) is based on the inhibition of telomerase in cancer cells. The antisense oligonucleotide 2'-O-methyl-RNA binding to the RNA component of telomerase acts as a selective telomerase inhibitor. We developed chitosan-coated polylactide-coglycolide (PLGA) nanoparticles to mediate efficient delivery of 2'-O-methyl-RNA into human lung cancer cells.

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Acid secretion or intragastric pH play a very important role in the pathophysiology of acid-related disorders such as peptic ulcer (PU), gastrooesophageal reflux disease (GERD) or nonsteroidal anti-inflammatory drug (NSAID)-induced gastrointestinal lesions. Proton pump inhibitors (PPIs) represent the most potent/effective antisecretory drugs for these indications. For the selection among the various agents (omeprazole/esomeprazole (CAS 73590-58-6/119141-88-7), pantoprazole (CAS 102625-70-7), lansoprazole (CAS103577-45-3), rabeprazole (CAS 117976-83-3)) some features of their pharmacokinetic (PK) and pharmacodynamic (PD) properties should be considered as the clinical outcome depends on systemic drug exposure (PK) and elevation of intragastric pH about certain threshold levels (PD).

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Aging involves progressive impairments in the functional reserve of multiple organs, which might also affect drug metabolism and pharmacokinetics. In addition, the elderly population will develop multiple diseases and, consequently, often has to take several drugs. As the hepatic first-pass effect of highly cleared drugs could be reduced (due to decreases in liver mass and perfusion), the bioavailability of some drugs can be increased in the elderly.

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Aim: Comparative potency of proton-pump inhibitors (PPIs) is an important clinical issue. Most available trials have compared the different PPIs at one or a few selected specific dosages, making it difficult to derive quantitative equivalence dosages. Here we derived PPI dose equivalents based on a comprehensive assessment of dose-dependent effects on intragastric pH.

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The antisense oligonucleotide 2'-O-methyl-RNA is a selective telomerase inhibitor targeting the telomerase RNA component and represents a potential candidate for anticancer therapy. The poor cellular uptake of 2'-O-methyl-RNA is a limiting factor that may contribute to the lack of functional efficacy. To improve delivery of 2'-O-methyl-RNA and consequently antitumoral efficiency in human lung cancer cells, we have investigated several transfection reagents.

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Background: Proton pump inhibitors (PPIs) represent drugs of first choice for treating peptic ulcer, Helicobacter pylori infection, gastrooesophageal reflux disease, nonsteroidal anti-inflammatory drug (NSAID)-induced gastrointestinal lesions (complications), and Zollinger-Ellison syndrome.

Results: The available agents (omeprazole/esomeprazole, lansoprazole, pantoprazole, and rabeprazole) differ somewhat in their pharmacokinetic properties (e.g.

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Cardiovascular drugs are characterized by wide inter-individual variability in dose/plasma concentration/ response (therapeutic and/or toxic) relationships. Therefore, some patients achieve good therapeutic response to their drug therapy, while others do not. Also, some patients experience adverse effects, which vary from mild to life-threatening.

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Drug treatment of epilepsy is characterized by unpredictability of efficacy, adverse drug reactions, and optimal doses in individual patients, which, at least in part, is a consequence of genetic variation. Since genetic variability in drug metabolism was reported to affect the treatment with phenytoin more than 25 years ago, the ultimate goal of pharmacogenetics is to use the genetic makeup of an individual to predict drug response and efficacy, as well as potential adverse drug events. However, determining the practical relevance of pharmacogenetic variants remains difficult, in part because of problems with study design and replication.

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Shortening of telomeres prevents cells from uncontrolled proliferation. Progressive telomere shortening occurs at each cell division until a critical telomeric length is reached. Telomerase expression is switched off after embryonic differentiation in most normal cells, but it is expressed in a very high percentage of tumors of different origin.

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Introduction: The proportion of the elderly is constantly increasing and by the year 2025 20% of the population will be above 65 years of age. With advanced age, subjects will develop multiple diseases and often need to take several drugs.

Discussion: This polypharmacy increases the risk for drug interactions and adverse effects.

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Background: Prevention of contrast media (CM) induced nephropathy (CIN) by prophylaxis (e.g. N-acetylcysteine; NAC) is controversially discussed.

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