Publications by authors named "Katarina Vielfort"

causes the most common sexually transmitted bacterial infection and trachoma, an eye infection. Untreated infections can lead to sequelae, such as infertility and ectopic pregnancy in women and blindness. We previously enhanced the antichlamydial activity of the fluoroquinolone ciprofloxacin by grafting a metal chelating moiety onto it.

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We herein present the synthesis of diversely functionalized pyrimidine fused thiazolino-2-pyridones KSO-mediated oxidative coupling of 6-amino-7-(aminomethyl)-thiazolino-2-pyridones with aldehydes. The developed protocol is mild, has wide substrate scope, and does not require transition metal catalyst or base. Some of the synthesized compounds have an ability to inhibit the formation of Amyloid-β fibrils associated with Alzheimer's disease, while others bind to mature amyloid-β and α-synuclein fibrils.

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is a strict intracellular bacterium that causes sexually transmitted infections and eye infections that can lead to life-long sequelae. Treatment options are limited to broad-spectrum antibiotics that disturb the commensal flora and contribute to selection of antibiotic-resistant bacteria. Hence, development of novel drugs that specifically target would be beneficial.

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70 kDa heat shock proteins (Hsp70) are essential chaperones of the protein quality control network; vital for cellular fitness and longevity. The four cytosolic Hsp70's in yeast, Ssa1-4, are thought to be functionally redundant but the absence of Ssa1 and Ssa2 causes a severe reduction in cellular reproduction and accelerates replicative aging. In our efforts to identify which Hsp70 activities are most important for longevity assurance, we systematically investigated the capacity of Ssa4 to carry out the different activities performed by Ssa1/2 by overproducing Ssa4 in cells lacking these Hsp70 chaperones.

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infections are a global health problem and new approaches to treat with drugs of high specificity would be valuable. A library of substituted ring fused 2-pyridones has been synthesized and evaluated for their ability to attenuate infectivity. pharmacokinetic studies were performed, with the best candidates demonstrating that a C8-methylsulfonamide substituent improved pharmacokinetic properties important for oral administration.

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The ability to introduce targeted genetic modifications in microbial genomes has revolutionized our ability to study the role and mode of action of individual bacterial virulence factors. Although the fastidious lifestyle of obligate intracellular bacterial pathogens poses a technical challenge to such manipulations, the last decade has produced significant advances in our ability to conduct molecular genetic analysis in Chlamydia trachomatis, a major bacterial agent of infertility and blindness. Similar approaches have not been established for the closely related veterinary Chlamydia spp.

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Caloric restriction (CR) extends the lifespan of flies, worms, and yeast by counteracting age-related oxidation of H2O2-scavenging peroxiredoxins (Prxs). Here, we show that increased dosage of the major cytosolic Prx in yeast, Tsa1, extends lifespan in an Hsp70 chaperone-dependent and CR-independent manner without increasing H2O2 scavenging or genome stability. We found that Tsa1 and Hsp70 physically interact and that hyperoxidation of Tsa1 by H2O2 is required for the recruitment of the Hsp70 chaperones and the Hsp104 disaggregase to misfolded and aggregated proteins during aging, but not heat stress.

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The host epithelium is both a barrier against, and the target for microbial infections. Maintaining regulated cell growth ensures an intact protective layer towards microbial-induced cellular damage. Neisseria gonorrhoeae infections disrupt host cell cycle regulation machinery and the infection causes DNA double strand breaks that delay progression through the G2/M phase.

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We investigated cell cycle progression in epithelial cervical ME-180 cells during colonization of three different Lactobacillus species utilizing live cell microscopy, bromodeoxyuridine incorporation assays, and flow cytometry. The colonization of these ME-180 cells by L. rhamnosus and L.

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Pancreatic β-cells secrete insulin in response to various stimuli to control blood glucose levels. This insulin release is the result of a complex interplay between signaling, membrane potential and intracellular calcium levels. Various nutritional and hormonal factors are involved in regulating this process.

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The constant shedding and renewal of epithelial cells maintain the protection of epithelial barriers. Interference with the processes of host cell-cycle regulation and barrier integrity permits the bacterial pathogen Neisseria gonorrhoeae to effectively colonize and invade epithelial cells. Here, we show that a gonococcal infection causes DNA damage in human non-tumor vaginal VK2/E6E7 cells with an increase of 700 DNA strand breaks per cell per hour as detected by an alkaline DNA unwinding assay.

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Polymorphonuclear neutrophils (PMNs) are important components of the human innate immune system and are rapidly recruited at the site of bacterial infection. Despite the effective phagocytic activity of PMNs, Neisseria gonorrhoeae infections are characterized by high survival within PMNs. We reveal a novel type IV pilus-mediated adherence of pathogenic Neisseria to the uropod (the rear) of polarized PMNs.

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Lactobacilli are normal inhabitants of our microbiota and are known to protect against pathogens. Neisseria gonorrhoeae is a human specific pathogenic bacterium that colonises the urogenital tract where it causes gonorrhoea. In this study we analysed early interactions between lactobacilli and gonococci and investigated how they compete for adherence to human epithelial cervical cells.

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