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Effective Therapeutics (effective + therapeutics)
Selected AbstractsBeta-lactam antibiotics: from antibiosis to resistance and bacteriologyAPMIS, Issue 1 2010KOK-FAI KONG Kong K-F, Schneper L, Mathee K. Beta-lactam antibiotics: from antibiosis to resistance and bacteriology. APMIS 2010; 118: 1,36. This review focuses on the era of antibiosis that led to a better understanding of bacterial morphology, in particular the cell wall component peptidoglycan. This is an effort to take readers on a tour de force from the concept of antibiosis, to the serendipity of antibiotics, evolution of beta-lactam development, and the molecular biology of antibiotic resistance. These areas of research have culminated in a deeper understanding of microbiology, particularly in the area of bacterial cell wall synthesis and recycling. In spite of this knowledge, which has enabled design of new even more effective therapeutics to combat bacterial infection and has provided new research tools, antibiotic resistance remains a worldwide health care problem. [source] Synthesis and assembly of a full-length human monoclonal antibody in algal chloroplastsBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2009Miller Tran Abstract Monoclonal antibodies can be effective therapeutics against a variety of human diseases, but currently marketed antibody-based drugs are very expensive compared to other therapeutic options. Here, we show that the eukaryotic green algae Chlamydomonas reinhardtii is capable of synthesizing and assembling a full-length IgG1 human monoclonal antibody (mAb) in transgenic chloroplasts. This antibody, 83K7C, is derived from a human IgG1 directed against anthrax protective antigen 83 (PA83), and has been shown to block the effects of anthrax toxin in animal models. Here we show that 83K7C heavy and light chain proteins expressed in the chloroplast accumulate as soluble proteins that assemble into complexes containing two heavy and two light chain proteins. The algal-expressed 83K7C binds PA83 in vitro with similar affinity to the mammalian-expressed 83K7C antibody. In addition, a second human IgG1 and a mouse IgG1 were also expressed and shown to properly assemble in algal chloroplast. These results show that chloroplasts have the ability to fold and assemble full-length human mAbs, and suggest the potential of algae as a platform for the cost effective production of complex human therapeutic proteins. Biotechnol. Bioeng. 2009; 104: 663,673 © 2009 Wiley Periodicals, Inc. [source] Inhibition of Amyloid Fibrillization of Hen Egg-White Lysozymes by Rifampicin and p -BenzoquinoneBIOTECHNOLOGY PROGRESS, Issue 3 2007Valerie H. Lieu It has been reported that more than 20 different human proteins can fold abnormally, resulting in the formation of pathological deposits and several lethal degenerative diseases. Despite extensive investigations on amyloid fibril formation, the detailed molecular mechanism remained rather elusive. The current research, utilizing hen egg-white lysozymes as a model system, is aimed at exploring inhibitory activities of two potential molecules against lysozyme fibril formation. We first demonstrated that the formation of lysozyme amyloid fibrils at pH 2.0 was markedly enhanced by the presence of agitation in comparison with its quiescent counterpart. Next, via numerous spectroscopic techniques and transmission electron microscopy, our results revealed that the inhibition of lysozyme amyloid formation by either rifampicin or its analogue p -benzoquinone followed a concentration-dependent fashion. Furthermore, while both inhibitors were shown to acquire an anti-aggregating and a disaggregating activity, rifampicin, in comparison with p -benzoquinone, served as a more effective inhibitor against in vitro amyloid fibrillogenesis of lysozyme. It is our belief that the data reported in this work will not only reinforce the findings validated by others that rifampicin and p -benzoquinone serve as two promising preventive molecules against amyloid fibrillogenesis, but also shed light on a rational design of effective therapeutics for amyloidogenic diseases. [source] Microarray analysis of changes in renal phenotype in the ethylene glycol rat model of urolithiasis: potential and pitfallsBJU INTERNATIONAL, Issue 4 2004Daniel H.-C. OBJECTIVES To investigate, in an initial study, the use of microarray analysis (MA) to develop an information base for urolithiasis. MA enables the screening of thousands of genes simultaneously making it the technique of choice for situations where the results are known, but the underlying mechanisms are not. Little is known about the pathological changes occurring in the kidney during urolithiasis and this has severely hampered efforts to develop effective therapeutics. MATERIALS AND METHODS Male rats were treated with 0.75% ethylene glycol for 2, 4 or 8 weeks; after death the kidneys were processed for RNA isolation and MA, conducted using a rat-based chip (one kidney/chip) and the results confirmed by reverse transcription-polymerase chain reaction (RT-PCR, 21 probe sets; control, four rats; treated, five rats). Targets were defined as different by the software if the fold change (FC) was ,,2, and sorted into functional categories using a data-mining tool. The repeatability of MA was investigated by subjecting the 4-week samples to MA in two independent runs. RESULTS The results for targets with a FC of , 2 were plotted (y = 1.01x , 0.75; r2 0.84). Comparing the results obtained by RT-PCR and MA showed a good qualitative correlation for those targets having a FC of ,,5 as determined by MA. Changes in the expression of genes associated with tubule function and regulation, oxidative damage, and inflammation were the most common in the functional categories. Changes in the expression of tubule-specific markers indicated that there was damage to the proximal (,-adducin, organic anion and cation transporters, sodium-hydrogen exchange protein-isoform 3) and distal tubules (,-adducin, kallikrein) at 2 and 4 weeks. Increased expression of mitochondrial uncoupling protein indicated that there were changes to the mitochondria and oxidative stress at 2 and 4 weeks. CONCLUSION This study shows the power of MA as an exploratory technique, and changes in the expression of several physiologically important genes whose expression has not previously been reported to be affected by hyperoxaluria or calcium oxalate crystalluria. [source] Insight Into the Kinetic of Amyloid , (1,42) Peptide Self-Aggregation: Elucidation of Inhibitors' Mechanism of ActionCHEMBIOCHEM, Issue 17 2007Manuela Bartolini Dr. Abstract The initial transition of amyloid , (1,42) (A,42) soluble monomers/small oligomers from unordered/,-helix to a ,-sheet-rich conformation represents a suitable target to design new potent inhibitors and to obtain effective therapeutics for Alzheimer's disease. Under optimized conditions, this reliable and reproducible CD kinetic study showed a three-step sigmoid profile that was characterized by a lag phase (prevailing unordered/,-helix conformation), an exponential growth phase (increasing ,-sheet secondary structure) and a plateau phase (prevailing ,-sheet secondary structure). This kinetic analysis brought insight into the inhibitors' mechanism of action. In fact, an increase in the duration of the lag phase can be related to the formation of an inhibitor,A, complex, in which the non-amyloidogenic conformation is stabilized. When the exponential rate is affected exclusively, such as in the case of Congo red and tetracycline, then the inhibitor affinity might be higher for the pleated ,-sheet structure. Finally, by adding the inhibitor at the end of the exponential phase, the soluble protofibrils can be disrupted and the A, amyloidogenic structure can revert into monomers/small oligomers. Congo red and tetracycline preferentially bind to amyloid in the ,-sheet conformation because both decreased the slope of the exponential growth, even if to a different extent, whereas no effect was observed for tacrine and galantamine. Some very preliminary indications can be derived about the structural requirements for binding to nonamyloidogenic or ,-sheet amyloid secondary structure for the development of potent antiaggregating agents. On these premises, memoquin, a multifunctional molecule that was designed to become a drug candidate for the treatment of Alzheimer's disease, was investigated under the reported circular dichroism assay and its anti-amyloidogenic mechanism of action was elucidated. [source] | |||||||||||||