Ehrlich II –2nd World Conference on Magic Bullets

Disulfiram as a New Promising Anticancer Drug CVEK B Palacky University, Olomouc, Czech Republic Proteasome: Proteasome is a giant protease responsible for degradation of about 90% of cellular proteins. Key signaling proteins are activated through proteasome processing (e.g. nuclear factor-κB); moreover, proteasome plays an important role in regulation of transcription and other crucial cellular events. Curiously enough, the proteasome has become an attractive target in cancer therapy as first-in-class proteasome inhibitor bortezomib (Velcade) was approved for clinical use against multiple myelome and mantle cell lymphoma. At the present time, there are plenty of ongoing clinical trials of bortezomib in various cancers. New use for old drug: An old drug against alcoholism, disulfiram (Antabuse), can create metal complexes which are potent proteasome inhibitors (Cvek & Dvorak Drug Discov Today 2008). Even further, disulfiram taken with zinc gluconate led to clinical remission in a patient with metastatic melanoma (Brar et al. Mol Cancer Ther 2004). There are substantial advantages of such “repurposing” of disulfiram: The drug (just because it is old) is cheap, safe, and is able to enter phase II clinical trials directly (Chong & Sullivan Nature 2007). JAMM domain inhibition: Molecular mechanism of such disulfiram-mediated proteasome inhibition is putatively based on interaction between the metal complexes and key zinc subunit (JAMM domain protein Poh1) of the proteasome (Cvek & Dvorak Curr Pharm Des 2007). This approach could be an attractive strategy for future proteasome targeting in patients (Gallery et al. Mol Cancer Ther 2007). Conclusions: Although there are two clinical trials of disulfiram as an anticancer agent listed in US National Cancer Institute database, they are not proteasome-focused (as disulfiram has other abilities to suppress cancer). Thus, potencial anticancer effects of disulfiram in the patients should be carefully evaluated in light of current knowledge on proteasome inhibition.

Behavioural and cellular consequences of excessive amounts of the powerful brain chemical dopamine LEBEL M and CYR M Neuroscience Research Group, UQTR, Trois-Rivières, Qué., Canada. Background: Parkinson’s disease is associated with severe degeneration of nigrostriatal dopamine producing neurons. Pharmacological dopamine replacement with its synthesis precursor, Levodopa, remains the most effective treatment for Parkinsonism. However, long term treatment with Levodopa leads to the emergence of abnormal involuntary movements known as dyskinesia. Here we demonstrate that high doses of levodopa, leading to excessive amounts of dopamine in the brain, could be toxic to neuronal cells. Results: Recently, we have demonstrated in cell cultures model and in rats striatum slices that activation of D1 receptors could regulate functions of structural proteins such as the microtubule associated protein tau. Whether dysfunctions in cytoskeletal-associated proteins are associated to Levodopa-induced dykinesia is unknown. This study investigated, in striatal neurons of 6-hydroxydopamine lesioned rats receiving or not Levodopa therapy, the expression and phosphorylation levels of tau. Our results demonstrated that, whereas dopamine depletion was without effects, intermittent administrations of Levodopa were associated with dyskinetic behaviours and had profound influence on tau phosphorylation. Conclusions: These data provided novel evidence that alterations in cytoskeletal constituents could play a role in the emergence of motor dysfunctions associated with dopamine replacement therapy.

Peritoneal Transport Dynamics of Icodextrin and Its Influence on The Membrane Permeability In Vitro CZYŻEWSKA K, GRZELAK T, SZARY B Poznan Univ. Med. Sci., Poznan, Poland Background: Glucose polymer (icodextrin) is used during peritoneal dialysis for development of an effective ultrafiltration. It has been proposed also as a carrier solution of antineoplastic drugs and a factor to reduce of adhesion formation during intraperitoneal chemotherapy. The aim of the presented study was the comparative analyses of the peritoneal transport dynamics of icodextrin in the different conditions and its effects on the transfer of small and large molecules across peritoneal membrane intact and chemically injured in vitro. The rabbit parietal peritoneum, modified Ussing chamber and mathematical model of mass transport were used to calculate the diffusive permeability coefficient (P) in cm x s^-1. Results: Icodextrin (7.5 g/dL) peritoneal transport in vitro, in the control conditions, directed from the interstitial (I) to the mesothelial (M) side of the membrane changes with time, but in the opposite direction is constant. Asymmetry of glucose polymer diffusion is observed: IM predominates over MI. Fluid stirring intensification and chemical injury by sodium deoxycholate enhance bidirectional transfer of icodextrin. MI transfer of icodextrin, but not IM is restricted more by tissue barriers than stagnant fluid layers. Glucose and gentamicin intensify (MI direction only) of the examined parameters, but methylglyoxal does not change the P values. Icodextrin modifies the transport dynamics of low and high molecular weight solutes across intact and mesothelium denuded peritoneum. For example it induces asymmetry of uric acid and albumin transport. IM transfer dominates MI transfer of uric acid. In contrast, in albumin transport MI was higher than IM. For the injured peritoneum the decrease in time of the bidirectional uric acid and urea transport, caused by icodextrin, is noted. Glucose polymer periodically augments and next diminishes gentamicin transfer directed from I to M side of the peritoneum. The decrease of antibiotics transport occurs also to the opposite direction. Conclusion: The results may be important for the clinical point of view. The increase of icodextrin absorption from the abdominal space to blood, during peritoneal dialysis, may have a negative impact on the efficacy of this therapy. In contrast, asymmetry of uric acid and albumin transperitoneal transport induced by icodextrin, may be observed in vivo, seems to be beneficial.

Dopamine transmission and the search for the ideal antidepressant drug D'AQUILA PS, SERRA G Department of Drug Sciences, University of Sassari, Sassari, Italy. Background: We examined (i) the relationship between antidepressant treatment and two stress regimes, Chronic Mild Stress (CMS) and Daily Restraint Stress (DRS), which differ in their ability to affect sensitivity to dopamine agonists and (ii) the effect of different antimanic drugs on antidepressant-induced dopaminergic supersensitivity. CMS, a model of depression, is based on the exposure to a variety of mild stressors (e.g. short periods of crowding, isolation, food and water deprivation etc.), DRS consists of daily sessions of 1 hour immobilization, and they result either in a decreased or in an increased sensitivity to dopamine agonists, respectively. Methods: Male Wistar or Sprague-Dawley rats were used. No-stress, CMS and DRS subjects were daily treated with the antidepressant desipramine. Stress and drug administration were commenced simultaneously and carried out for 7 weeks. The antimanic drugs lithium, carbamazepine and valproate, in three different experiments, were coadministered with the antidepressant imipramine for 3-4 weeks. After the chronic drug/stress treatments, the subjects were challenged with the dopamine D2-like agonist quinpirole and the motor response was measured. Results: As expected, antidepressants and DRS potentiated while CMS reduced the motor response to quinpirole. Desipramine countered stress effect in both cases. Carbamazepine, but neither lithium nor valproate, prevented the imipramine-induced potentiation, an effect likely due to liver enzymatic induction. Conclusions: 1) Countering stress effect on dopaminergic sensitivity, rather than just inducing a potentiation, might be what matters to attain the antidepressant therapeutic effect. 2) The failure of antimanic treatments to prevent dopaminergic supersensitivity might reflect their poor efficacy in treating antidepressant-induced manic switches, thus providing the basis for a possible model of antidepressant-induced mania.

Ras as a target for exploratory study of monoterpene perillyl alcohol intranasal administration in patients with recurrent gliomas DA FONSECA CO Associate Professor of Neurosurgery, Universidade Federal Fluminense, Brazil. Upon completion of his master´s degree in medical genetics at the Federal Rio de Janeiro University in 2003, Dr Fonseca joined the Laboratório de Patologia Celular – Departamento de Biologia Celular, of the Federal Fluminense University where he directed research in basic câncer research with translational research. This led to the development of invention of new approach for delivery drugs for malignant gliomas. He concludes PhD Thesis “Exploratory study of monoterpene perillyl alcohol intranasal administration in patients with recurrent gliomas” in 2007. Dr Fonseca pioneered a new technology, intranasal administration of monoterpene perillyl alcohol. Intranasal administration of perillyl alcohol is not only an unique delivery method, but the use of perillyl alcohol as a novel chemotherapeutic agent inhibiting the ras pathway is extremely exciting. His results have demonstrated that intranasal perillyl alcohol will soon be able technique in armamentarium against malignant gliomas (Da Fonseca et al 2006; Da Fonseca et al 2006; Da Fonseca et al in press). It is expected that this work will lead development of methods for combine drugs with different therapeutic targets.

Methotrexate (MTX) Induces Permanent Growth Arrest in Human Adenocarcinoma Cells DABROWSKA M^1, MOSIENIAK G^1, SIKORA E^1, RODE W^1 ^1Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland. Background: MTX is a classic antifolate successfully used in cancer chemotherapy for nearly 60 years. MTX was found to induce apoptosis, senescence or differentiation as treatment outcomes in various cancerous cell types. A major hurdle in MTX cytostatic efficacy is resistance to the drug. The present study is aimed at characterization of response of human adenocarcinoma C85 cells to clinically relevant MTX doses. Methods: CytoTox-One Homogeneous Membrane Integrity assay (Promega) was performed on C85 cells exposed to MTX concentrations ranging between 10^-9 – 10^-5M. Growth arrest was followed by 5-bromo-2-deoxyuridine (BrdU) incorporation assay in cells either exposed to 1 µM MTX or exposed to 1 µM MTX and allowed to recover after treatment. Cell cycle distribution of cells exposed to 1 µM MTX for 48 h and allowed to recover for subsequent 96 h, was analyzed using BD FACSCalibur flow cytometer and CellQuest software. Western blot analysis was employed to determine p21^Waf1/Cip1, p16^INK4a and dihydrofolate reductase (DHFR) levels in C85 cells treated as in the case of cell cycle analysis. Senescence-associated β-galactosidase (SA-β-Gal) activity was visualized microscopically in C85 cells allowed to recover for 96 h after 48 h exposure to 1 µM MTX, using 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside as a chromogenic substrate. Results: LDH release from C85 cells exposed to MTX showed the lowest rate for cells treated with 10 µM MTX for 48 h and allowed to recover for 72 h, with 14-fold reduction vs. cells grown under control conditions (each experiment performed in triplicate). In cells allowed to recover for 48 or 96 h after 48 h exposure to 1 µM MTX, BrdU incorporation was reduced by 80% (average from three experiments). Fraction of polyploid cells remained constant at 10% level in (i) control cells, (ii) cells exposed to 1 µM MTX for 48 h and (iii) cells exposed to 1 µM MTX for 48 h and allowed to recover for 96 h. In the course of MTX exposure and recovery, p16^INK4a expression was reduced, p21^Waf1/Cip1 induced but DHFR level was maintained. Conclusions: MTX-induced senescence in C85 cells is manifested by a permanent G1 phase growth arrest, SA-β-Gal expression and induction of p21^Waf1/Cip1 expression. It is not accompanied by any increase in polyploidy and, despite apparent growth arrest, no change of DHFR level is observed.

The Effect of 4Hz (30dB) Infrasound on Heart Muscle Contractility DADASYAN E, AYRAPETYAN G UNESCO Chair-Life Sciences International Postgraduate Educational Center, Yerevan, Armenia Background: Previously was shown that Infrasound (IS) at 4 Hz (30dB) frequency had modulating effect on heart muscle contractility. The molecular mechanism underlying this influence is not clear yet. The purpose of the present work is to study the molecular mechanism of infrasound. We have studied the effect of 4Hz (30dB) infrasound on heart muscle contractility, and Na/K pomp activity. We also measured the intracellular concentration of Ca^2+ ions by ^45Ca, and the content of intracellular cyclic nucleotides (cAMP, cGMP). Methods: Removed snail (Helix pomatia) hearts were cannulated and suspended in bath with physiological solution (PS). PS was exposed to 4Hz (30dB) IS for 30 minutes. ^45Ca uptake by muscles incubated in normal and IS-treated PS was measured by ^45Ca isotope. ^45Ca-uptake and intracellular cyclic nucleotides contents (cAMP and cGMP) were measured by Wallac 1450 liquid scintillation counter. Results: IS at 4 Hz (30dB) frequency increased the amplitude and frequency of heart muscle contractility as well as the intracellular Ca^2+ ions concentration. By measuring the content of intracellular cyclic nucleotides (cAMP, cGMP) we observed that by the increase of intracellular Ca^2+ concentration caused the increase of cGMP content and decrease of cAMP contents in the cells. Figure The effects of 4Hz (30dB) IS treated PS on the intracellular contents of cGMP and cAMP of heart muscle. Conclusions: It is suggested that IS at 4Hz frequency and (30dB) intensity –induced transient relaxation of heart muscles caused the activation of Na/K pump in result of the increase of cGMP-dependent Ca efflux.

Genetic immunization: comparison of water-in-oil liposome-based delivery of cDNAs with in vivo electroporation. DAFTARIAN P^1,2; MANSOUR M^3; CHOWDHURY R^1; BROWN RG^3;  KENYON N^1; LEMMON V^4  1. Wallace H. Coulter Center for Translational Research, University of Miami Miller School of Medicine, Miami, FL. 2. Department of Microbiology & Immunology, University of Miami Miller School of Medicine, Miami, FL. 3. ImmunoVaccine Technologies Inc. Halifax NS, Canada. 4. Miami Project to Cure Paralysis, University of Miami Miller School of Medicine, Miami, FL.  With the current shift from genomics to proteomics, monoclonal antibodies (mAbs) are expected to become a $50 billion market by the year 2012. However, making truly useful monoclonal antibodies that target native forms of proteins has been hampered by challenges in protein production and purification. Membrane proteins, for instance, are difficult to purify yet are among the best candidates for drug development because 50% of the current drugs on the market work via membrane proteins. We have developed improved methods that bypass the need for purification of proteins for immunization or for the screening of hybridoma supernatants.  We have used two different DNA delivery methods into mice: (I) "in vivo electroporation", using CUY21SC from Protech International, Inc., and (II) water-in-oil liposome-based platform from ImmunoVaccine Technologies.  The genes of interest (such as Human L1) were placed downstream of the immediate early promoter/enhancer sequences of cytomegalovirus intron A immediate-early (IE) gene. Mice received 100 µg of plasmid by intra-dermal injection. Sera and positive clones were screened using an improved FLISA screen on fixed/permeablized/blocked Cos-7 cells transfected with the genes of interest plated in 96-well plates and read by LI-COR Odyssey.  Fusions were performed using Stemcell Technologies fusion protocol modified to take advantage of a stereo Video microscope for picking clones.  While both immunization protocols resulted in strong protein expression/immune responses, in vivo electroporation resulted in the expression of protein mainly in the injection site reaction while the water-in-oil liposome emulsion directed the expression of the delivered gene into the lymph nodes. Collectively, these methods increase the breath, magnitude, and durability of immune responses to native antigens and importantly, eliminate the need to produce and purify large quantities of protein for immunization, dramatically reducing monoclonal antibody production costs. Incidentally, our data suggest that described methods may be used for nucleotide delivery in general such siRNA, RNA and DNA.   Acknowledgements Protech International, Inc. for providing the electroporator and electrodes. ImmunoVaccine Technologies Inc. for providing the water-in-oil liposome platform. Development costs supported by the Wallace H. Coulter Center for Translational Research and the University of Miami Neuroscience Center.

Personalized Prevention of Colorectal Neoplasia: High Magnesium and Low Calcium among People with a Functional Polymorphism in the Magnesium Transporter DAI Q, SHRUBSOLE M, NESS RM, SCHLUNDT D, CAI Q, SMALLEY WE, LI M, SHYR Y, ZHENG W Vanderbilt University, Nashville, USA Background Growing evidence from studies conducted in Western societies has linked low intake of magnesium to insulin resistance and systemic inflammation and, thus, risk of diseases common in Western countries, such as colorectal cancer, type II diabetes and coronary heart disease. Migration studies found that after moving to Western societies, the incidence of the aforementioned diseases in East Asian immigrants, a population with traditionally low risks, approached that for Caucasians. We found that mean intake of magnesium in the US population is, however, not different or even slightly higher than that in East Asia. Instead, the ratio of calcium to magnesium intake is much higher in the US population (2.8)than in East Asia (1.6). Transient receptor potential melastatin 7 (TRPM7) is a newly found gene essential to magnesium absorption and homeostasis. Methods: To test whether the association of colorectal polyps with intake of calcium and/or magnesium and Thr1482Ile polymorphism in the TRPM7 gene is modified by the calcium/magnesium intake ratio. Included in the study were a total of 688 adenoma cases, 210 hyperplastic polyp cases, and 1,306 polyp-free controls from The Tennessee Colorectal Polyp Study (TCPS). Results We found total magnesium consumption was linked to a significantly reduced risk of colorectal adenoma, particularly for those with a low calcium/magnesium ratio. An inverse association trend was found for hyperplastic polyps. Further, we found the common Thr1482Ile polymorphism was associated with an elevated risk of both adenomatous and hyperplastic polyps. Moreover, this polymorphism significantly interacted with the calcium/magnesium intake ratio in relation to both adenomatous and hyperplastic polyps. People who carry at least one 1482Ile allele, and if they consumed diets with a high calcium/magnesium ratio, were particularly at an elevated risk of adenoma (odds ratio (OR) =1.60, 95% confidence interval (CI) =1.12-2.29) and hyperplastic polyps (OR=1.85, 95%CI=1.09-3.14) vs. those who do not carry the polymorphism. We will also update novel unpublished findings in the presentation. Conclusions These findings, if confirmed, may provide a new avenue for the personalized prevention of magnesium deficiency and, thus, colorectal cancer.

Cyclotides, ultrastable peptide frameworks for magic bullet drug delivery DALY NL^1, GUNASEKERA S^1, FOLEY F^1, CLARK RJ^1, FABRI, L^2, CRAIK DJ^1 ^1Institute for Molecular Bioscience, University of Queensland. 4072 Australia. ^2CSL Richmond Victoria, Australia. Background: Cyclotides are plant derived mini-proteins with compact folded structures and exceptional stability. Their stability derives from a head-to-tail cyclized backbone coupled with a cystine knot arrangement of three-conserved disulfide bonds. Taking advantage of this stable framework we developed novel VEGF-A antagonists by grafting a peptide epitope involved in VEGF-A antagonism onto the stable cyclotide framework. Antagonists of this kind have potential therapeutic applications in diseases where angiogenesis is an important component of disease progression, including cancer and rheumatoid arthritis. Methods: This study involved the use of solid phase peptide synthesis to produce several analogues of the prototypic cyclotide kalata B1 with a poly-arginine epitope that specifically inhibits the interaction of VEGF with the KDR receptor, grafted into the backbone. The peptides were cyclized and oxidized and their structures analzyed using NMR spectroscopy. Their biolgoical activity was assessed in a cell based VEGF-A antagonism assay and their in vitro stability determined in human serum. Results: The grafted peptides were successfully cyclized and oxidized and maintained the native cyclic cystine knot fold. Furthermore the grafted peptides were more stable in human serum than the linear poly R epitope. The most active analogue was a graft into loop 3, which showed low micromolar activity in the VEGF-A antagonism assay. Calculation of the three-dimensional structures suggested that disorder in the poly R region might allow adaptation to the receptor site and facilitate biological activity. Conclusions: We confirmed that a range of grafted cyclotide analogues can be synthesized and form a cystine knot motif with stability in human serum. The large number of known cyclotide sequences, which can be thought of as nature’s combinatorial library of cyclotides, helped to direct the design process for the grafted analogues. Biological activity was maintained in one of the grafted analogues, validating the potential of this framework in drug design. Given that the epitope grafted into the scaffold differs significantly from the native sequence, it appears likely that the cyclotide framework can accommodate a wide range of epitopes, broadening its scope in drug design.

Insulin Suppresses High Mobility Group-B1 (HMG-B1) Protein and Toll Like Receptor Expression: Further Evidence of its Anti-Inflammatory Effect DANDONA P Kaleida Health, State University of New York at Buffalo We have previously shown that insulin at low doses exerts a potent and rapid anti-inflammatory effect through the suppression of pro-inflammatory transcription factors, NFkB and Egr-1. In addition, insulin suppresses plasma CRP, SAA and PAI-1 concentrations and may reduce the size of the infarct in patients with acute myocardial infarction. Our recent work has demonstrated that the expression of toll like receptors, TLR-2 which recognizes gram positive bacterial lipopeptides, and, TLR-4 which is the specific receptor for endotoxin, is also suppressed by insulin infused at a low dose (2U/h). Insulin also suppresses the activity of PU.1, the transcription factor which regulates TLR expression. TLRs 4 and 2 mediate inflammation induced by endotoxin and Gram positive bacteria while they are also known to mediate diet induced obesity related insulin resistance and injury related to ischemia/reperfusion. Thus, insulin may have potentially important therapeutic effects in endotoxemia, bacteremia and septicemia. Our most recent work shows that a low dose infusion of insulin (2U/h) leads to a reduction in the expression of HMG-B1, an intranuclear chromatin related protein which is able to open the nucleosomes such that gene promoters are can be bound by RNA polymerase II and pro-inflammatory transcription factors leading to the transcription of inflammatory genes. Since endotoxin induced inflammation is mediated by TLR-4 (receptor for endotoxin) and NFkB whose action is amplified by HMG-B1, these actions of insulin are appropriate for controlling endotoxin induced inflammation. Our most recent work also shows that the intake of cream and a high fat high carbohydrate meal results in an increase in plasma endotoxin concentrations and may therefore contribute to post prandial oxidative stress and inflammation. Thus, the natural post prandial increase in insulin may neutralize the effects of macronutrient related increase in endotoxin. Corticosteroids are the most commonly used anti-inflammatory agents and therefore we examined the effect of hydrocortisone on these indices. It is of interest that a high dose of hydrocortisone does not affect the expression of TLR-4 while it paradoxically increases the expression of HMG-B1. Clearly, therefore, insulin is potentially the ideal agent for controlling endotoxin induced inflammation. These actions may have contributed to the success of previously reported studies using insulin in the setting of intensive care. More prospective controlled studies are required for insulin alone and in combination with corticosteroids. Furthermore, the cardioprotective effect of insulin related to its vasodilatory, anti-inflammatory, anti-platelet, anti-thrombotic and anti-apoptotic actions is currently being tested by us in 600 patients with acute anterior ST elevation myocardial infarction in a prospective study measuring the size of the infarct MRI to demonstrate a reduction in the size of the infarct. Our work has clearly opened up several areas of inflammation and cardioprotection which require careful investigation for the potential novel beneficial effects of insulin.

Bis(2-aminoimidazolinium)diphenyl Compounds as DNA Minor Groove Binders with in Vivo Antitrypanosomal and Antimalarial Activity: the cation is important. Dardonville C^1; Mascaraque A^1; Nieto L^1; Rodríguez F^2; Rozas I^2; Kaiser M^3; Brun R^3; Nguyen B^4; Wilson WD^4 ^1Institute of Medicinal Chemistry, CSIC, Madrid, Spain; ^2School of Chemistry, Trinity College Dublin, Ireland; ^3Swiss Tropical Institute, Basel, Switzerland; ^4Department of Chemistry, Georgia State University, Atlanta, USA. Background: A pragmatic approach to the discovery of new drugs for neglected diseases is the “recycling” of available compounds. We have successfully applied this strategy during the last years with the (re)discovery of an attractive class of compounds (i.e., 2-aminoimidazolinium derivatives) showing excellent in vivo activity against T. brucei rhodesiense and P. falciparum, the ethiological agents of rhodesiense sleeping sickness and severe malaria, respectively. Methods: Based on their structural similarity with known antitrypanosomal and antimalarial agents, several series of dicationic compounds as well as their monocationic and neutral analogues were screened in vitro against T. b. rhodesiense, P. falciparum, and rat skeletal myoblast L6-cells as control for cytotoxicity. The compounds showing the highest activity and acceptable selectivity were assayed in vivo in models of acute and chronic T. brucei infections (STIB900 and GVR35 strains, respectively), and murine malaria (P. berghei). Their interaction with the DNA minor groove was also measured by thermal melting curves (Tm) and SPR experiments on AT sequence DNA polymers. Results: Several dicationic leads with nM in vitro activity and excellent selectivity against T. b. rhodesiense and P. falciparum were identified. A number of compounds cured 100% of the mice infected with T. b. rhodesiense and 4 compounds reduced the parasitemia in mice infected with P. berghei. A correlation between DNA binding affinity and trypanocidal activity was observed, indicating that DNA binding may be part of their mechanism of action. Most importantly, we found that the 2-aminoimidazoline cation afforded molecules with superior safety profile compared with its guanidine counterpart. Conclusion: 1) The rational screening of in-house libraries of compounds is a validated approach to find new drug leads for neglected diseases. 2) Bis(2-aminoimidazoline) derivatives represent a very promising class of DNA minor groove binding agents that have already demonstrated their antiprotozoal potential in vivo.

Dentistry and Antibiotic Resistance: The Need to Set Guidelines and Improve Prescribing Practices. DAR-ODEH NS^1, ABU-HAMMAD OA^2 ^1 Department of Oral Surgery, Oral Medicine, and Periodontics, Faculty of Dentistry, University of Jordan, Amman, Jordan; ^2 Department of Prosthodontics, Faculty of Dentistry, University of Jordan, Amman, Jordan Background: In the last decade, there has been an increasing interest in investigating antibiotic use by dentists. Aims: This study aims to evaluate 1) The degree of knowledge that the dental profession has, concerning therapeutic uses of antibiotics. Practices and knowledge of dentists worldwide will be assessed. 2) Deficits in our knowledge about antibiotics, and controversies about the correct use of antibiotics, will also be highlighted. Methods: A literature review was performed in Pubmed during May and June- 2008 using the keywords: antibiotics, dentistry, prescription. All articles that were written in English and which investigated dentists' knowledge about antibiotics in different countries were reviewed. Results: A large gap in knowledge was found between dentists practicing in Europe and North America and dentists who work in developing countries. Defects in knowledge about antibiotics were mainly in the fields of: indications for the use of therapeutic antibiotics, duration of antibiotic therapy, and alternatives to penicillin in penicillin-allergic patients. Conclusions: More appropriate methods for dental treatment should be employed to reduce unnecessaary antibiotics consumption. These methods may include appropriate dental treatment, analgesic therapy, and education of the patient. The medical and dental schools should improve their curriculum of microbiology. Efforts should be united to counteract this problem by encouraging collaboration of experts and scientists as well as decision-makers worldwide.

The Role of PPARγ Agonist in Alzheimer’s disease. DASH SK, CHANDY MJ Department of Neurosciences, Apollo Hospitals Dhaka, Bangladesh. Abstract--Alzheimer’s disease is the most common cause of dementia. The increasing prevalence of the disease presents a challenge to the treating neurologist. Presently the drugs used for Alzheimer’s disease produce only symptomatic improvement. Currently various therapeutic strategies are under development for the treatment and prevention of Alzheimer’s disease, like γ secretase inhibitors, immunotherapy with anti Aβ antibodies,Aβ immunization, metal protein attenuation compounds, and peroxysomal proliferators activated receptors γ agonist,NSAIDS. Alzheimer’s disease has a marked inflammatory component. It is proposed that anti inflammatory therapies may be of value in Alzheimer’s disease. PPARS are members of nuclear hormone receptor super families that are activated by lipids in regulating inflammatory responses. PPARγ has been investigated in animal model for its role due to its anti inflammatory action in various C.N.S. diseases, having an inflammatory component. PPAR γ agonists have been demonstrated to suppress amyloid β mediated activation of microglia in vitro and to prevent cortical and hippocampal neuronal death. Various studies have shown that PPAR γ agonists may be of value in treatment of Alzheimer’s disease in animal models. The details of PPARγ agonists as a therapeutic target for the treatment of Alzheimer’s disease will be discussed. Abbreviations.-PPARγ (Peroxysomal Proliferators Receptor Activator Gamma), Aβ (Amyloid beta), NSAIDS (Nonsteroidal Anti-Inflammatory Drugs), C.N.S. (Central Nervous System).

Experimental studies on antimicrobial potentialities of antipsychotics and antiinflammatory drugs with special reference to their action on Mycobacterium tuberculosis DASTIDAR SG, DASGUPTA A Herbicure Healthcare Bio-Herbal Research Foundation Metro Garden City, D.H. Road, Kolkata 700 104, India Background: Excessive and inadvertent use of antibiotics and antibacterial chemotherapeutics has caused a significant increase in the occurrence of drug resistant pathogens including M. tuberculosis. Systematic search among various pharmacological categories of drugs have revealed that many of them possess potent antimicrobial property. Methods: The antipsychotics and antiinflammatory drugs were tested in vitro against 300 to 500 bacteria including two cag positive H. pylori and 45 mycobacteria. The MIC was determined by agar dilution technique following NCCLS guidelines along with detection of bactericidal/bacteriostatic action. Intensive in vivo experiments were carried out in mice employing S. enteritidis var typhimurium and M. tuberculosis H37Rv. Protection against V. cholerae was established in rabbit ileal loop model. Results: Antipsychotic drugs fluphenazine, flupenthixol, trifluoperazine and antiinflammatory agent diclofenac sodium possess remarkable antimicrobial effect against clinical isolates of Gram positive and Gram negative types. Diclofenac was found to inhibit synthesis of bacterial DNA. These compounds when injected intraperitoneally significantly protected Swiss white mice from the lethality of Salmonella infection. When tested in vitro these drugs could inhibit mycobacteria at 10-25?g/ml level. Diclofenac sodium when injected at 10 ?g/gm body weight resulted in statistically significant survival (p<0.01 according to ?2 test) of mice challenged with 50MLD of M. tuberculosis H37Rv. Flupenthixol provided visible inhibition in the ballooning of rabbit ileal loop infected with V. cholerae 569B. Conclusion: Definite detection of antibacterial particularly antitubercular functions in antipsychotics and antiinflammatory drugs may prove to have a profound impact in the treatment of various infections including tuberculosis. In course of time it will be possible to create a new generation of potential antimicrobics by suitable structural modification of these agents. Thus development of novel chemotherapeutic compounds would retain a paramount legacy in the history of therapy of infections as envisaged by Paul Ehrlich.