Natural competence is the principal driver of streptococcal evolution. While acquisition of new traits could facilitate rapid fitness improvement for bacteria, entry into the competent state is a highly orchestrated event, involving an interplay between various pathways. We present a new type of competence-predation coordination mechanism in Streptococcus sanguinis.
View Article and Find Full Text PDFis an early colonizer of the oral microbiome with documented bactericidal activity against the oral pathogen . has been observed to possess the typical competence regulon found within most oral streptococci; however, the competence-stimulating peptide (CSP) responsible for QS activation and the regulatory role of the competence regulon is yet to be explored. Herein, we have both confirmed the identity of the CSP and utilized a wide range of phenotypic assays to characterize its regulatory role in competence, biofilm formation, and hydrogen peroxide formation.
View Article and Find Full Text PDFsubsp. is an emerging opportunistic pathogen responsible for septicemia and endocarditis in the elderly. Invasive infections by subsp.
View Article and Find Full Text PDFThe emergence and spread of multidrug resistant (MDR) pathogens with acquired resistance to almost all available antimicrobial agents has severely threatened the international healthcare community over the last two decades. The last resort antibiotic vancomycin is critical for treatment of several of these pathogens; howeverc vancomycin resistance is spreading due to the undesired accumulation of IV vancomycin in the colon post-treatment. This accumulation exerts selective pressure upon members of the colonic microflora, including , which possess vancomycin resistance genes.
View Article and Find Full Text PDFCyclic peptide scaffolds are key components of signal transduction pathways in both prokaryotic and eukaryotic organisms since they act as chemical messengers that activate or inhibit specific cognate receptors. In prokaryotic organisms these peptides are utilized in non-essential pathways, such as quorum sensing, that are responsible for virulence and pathogenicity. In the more evolved eukaryotic systems, cyclic peptide hormones play a key role in the regulation of the overall function of multicellular organisms, mainly through the endocrine system.
View Article and Find Full Text PDFTumor cell subpopulations called cancer stem cells (CSCs) or tumor-initiating cells (TICs) have self-renewal potential and are thought to drive metastasis and tumor formation. Data suggest that these cells are resistant to current chemotherapy and radiation therapy treatments, leading to cancer recurrence. Therefore, finding new drugs and/or drug combinations that cause death of both the differentiated tumor cells as well as CSC populations is a critical unmet medical need.
View Article and Find Full Text PDFBundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz
August 2010
The education of medical professionals is divided into medical studies, postgraduate training leading to the qualification as a specialist, and continuing professional development. During education, all scientific knowledge and practical skills are to be acquired, which enable the physician to practice responsibly in a specialized medical area. In the present article, relevant curricula are analyzed regarding the consideration of medical device-related topics, as the clinical application of medical technology has reached a central position in modern patient care.
View Article and Find Full Text PDFG-protein-coupled receptors (GPCR) participate in many disease pathways and represent the largest family of therapeutic targets. Thus, great investments are made to discover drugs modulating GPCR-mediated events. Among functional assays for screening GPCRs, the Transfluor imaging assay is based on redistribution of cytosolic beta-arrestin to an activated GPCR and has become widely used in high-content screening.
View Article and Find Full Text PDFThe recently identified mas-related-gene (MRG) family of receptors, located primarily in sensory neurons of the dorsal root ganglion, has been implicated in the perception of pain. Thus, antagonists of this class of receptors have been postulated to be useful analgesics. Toward this end, we developed a cell-based beta-lactamase (BLA) reporter gene assay to identify small molecule antagonists of the human MRG-X1 receptor from a library of compounds.
View Article and Find Full Text PDFAssay Drug Dev Technol
February 2005
Cell-based functional assays are becoming popular in many HTS laboratories because of recent advances in detection and automation technologies. However, the supply of large amounts of live cells with consistent cellular response for day-to-day screening operations over several days/weeks is a tremendous challenge. The high cost of cell culture, labor-intensive nature of the work, and inherent variability in cellular responses from time to time tend to be prohibitive for extensive applications of cell-based assays in HTS.
View Article and Find Full Text PDFThe measurement of intracellular calcium response transients in living mammalian cells is a popular functional assay for identification of agonists and antagonists to receptors or channels of pharmacological interest. In recent years, advances in fluorescence-based detection techniques and automation technologies have facilitated the adaptation of this assay to 384-well microplate format high-throughput screening (HTS) assays. However, the cost and time required performing the intracellular calcium HTS assays in the 384-well format can be prohibitive for HTS campaigns of greater than 1 x 10(6) wells.
View Article and Find Full Text PDFThe efficacy-safety and pharmacokinetics of the six-dose regimen of artemether-lumefantrine (Coartem/Riamet; Novartis Pharma AG, Basel, Switzerland) were assessed in a randomized trial in 219 patients (> or = 12 years old) with acute, uncomplicated Plasmodium falciparum malaria in Thailand. One hundred and sixty-four patients received artemether-lumefantrine and 55 received the standard treatment combination of mefloquine-artesunate. Both drugs induced rapid clearance of parasites and malaria symptoms.
View Article and Find Full Text PDFCurrent chemotherapy for the treatment of infections caused by the liver fluke Fasciola hepatica is not satisfactory. Therefore, the efficacy and tolerability of triclabendazole (TCZ) was assessed for this indication. Eighty-two patients (51 female, 31 male, age 15-81 yr, mean 42 yr) with chronic or latent F.
View Article and Find Full Text PDFTrans R Soc Trop Med Hyg
February 2001
The efficacy and safety of the 6-dose regimen of artemether-lumefantrine were assessed in an open randomized trial in children and adults presenting with acute, uncomplicated Plasmodium falciparum malaria in Thailand between November 1997 and March 1998. 200 patients were enrolled in 2 centres: 150 received artemether-lumefantrine (i.e.
View Article and Find Full Text PDFIn India, treatment of acute, uncomplicated Plasmodium falciparum malaria is becoming increasingly difficult due to resistance to chloroquine, thus there is a need for new antimalarial drugs. CGP 56697 (co-artemether), a new drug, is a combination of artemether and lumefantrine in a single oral formulation (one tablet = 20 mg of artemether plus 120 mg of lumefantrine). In a double-blind study, 179 patients with acute uncomplicated P.
View Article and Find Full Text PDFThe pharmacokinetics of benflumetol as a fixed combination, artemether-benflumetol (CGP 56697), following three regimens [regimen A: four tablets at 0, 8, 24 and 48 h (320 mg artemether, 1,920 mg benflumetol); regimen B: two tablets at 0, 8, 24 and 48 h (160 mg artemether, 960 mg benflumetol); regimen C: four tablets at 0, 8 and 24 h (240 mg artemether, 1,440 mg benflumetol)] were investigated in 39 patients with acute uncomplicated falciparum malaria. All patients showed a rapid initial response with a median parasite clearance time of 40, 41 and 39.5 h and a fever clearance time of 27.
View Article and Find Full Text PDFTrop Med Int Health
November 1999
Diagnosis of infection with the liver fluke Fasciola hepatica is usually difficult. Ultrasonography (US) might be a useful diagnostic alternative, and we assessed the value of sequential US in the diagnosis and monitoring of fascioliasis in 76 patients at baseline and for 60 days after treatment with triclabendazole. At baseline, biliary abnormalities were observed in 52 patients.
View Article and Find Full Text PDFCGP 56697 (Riamet) is a new oral anti-malarial drug composed of artemether and lumefantrine (benflumetol) which combines the fast, short-acting artemether for rapid parasite clearance with the prolonged action of lumefantrine for intended radical cure. In this double-blind, comparative trial, the efficacy and tolerability of CGP 56697, given as a course of 4 x 4 tablets over 48 h, was compared to halofantrine, given as 3 x 2 tablets over 12 h with a second course 1 week later. Patients (mostly non-immune) with acute, uncomplicated Plasmodium falciparum infection were randomly assigned to either CGP 56697 (n = 51) or halofantrine (n = 52).
View Article and Find Full Text PDFMultiple dose pharmacokinetics of artemether and dihydroartemisinin were investigated in chinese patients treated for malaria. They received over 2 days either 4 x 80 mg artemether orally (n = 48) or 4 x 80-480 mg co-artemether (n = 40), a combination of artemether and lumefantrine (benflumetol). Lag time = 0.
View Article and Find Full Text PDFCoartemether is a fixed 1:6 ratio of artemether and lumefantrine (benflumetol), a joint development between Novartis Pharma and the Academy of Military Medical Sciences (Beijing, China). It is well tolerated and has a high efficacy against uncomplicated and drug resistant falciparum malaria by oral administration. The preclinical profile of coartemether revealed no prohibitive toxicological, teratogenic or mutagenic findings.
View Article and Find Full Text PDFBr J Clin Pharmacol
December 1998
Aims: To investigate the pharmacokinetic and pharmacodynamic properties of artemether and benflumetol in a fixed combination tablet (CGP 56697) and to offer an explanation for the lower than expected cure rate in a Thai clinical trial.
Methods: Two hundred and sixty patients were enrolled into a randomized, double-blind, parallel group, dose-finding trial. CGP 56697 was given orally, either as: A, 4 x 4 tablets over 48 h; B, 4 x 2 tablets over 48 h or C, 3 x 4 tablets over 24 h.
Aims: Preliminary results indicate higher absorption of triclabendazole (TCBZ) administered postprandially. Therefore, the influence of food on the pharmacokinetics of TCBZ and its active sulphoxide (TCBZ-SO) and sulphone (TCBZ-SO2) metabolites was investigated.
Methods: Two single doses (10 mg kg(-1)) of TCBZ were administered to 20 patients with fascioliasis.
A randomized, open trial involving 260 Tanzanian children, aged 1-5 years, with acute Plasmodium falciparum malaria was conducted to evaluate the efficacy of the combination antimalarial CGP 56697 (artemether and benflumetol), and to compare it with chloroquine, the standard drug used for malaria treatment in the Kilombero area. Children who had received rescue medication within the first 48 h or had a negative slide at the same time were excluded. Seven-day parasitological cure rates were 94% (95% CI 88-97.
View Article and Find Full Text PDFObjective: To test the efficacy of a new compound drug (CGP 56697) against acute, uncomplicated falciparum malaria.
Method: Reappearing parasites were analysed by PCR-RFLP within a randomized controlled trial. 130 patients received chloroquine and 130 patients were treated with CGP 56697.