Ehrlich II –2nd World Conference on Magic Bullets



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Xenon: a magic bullet for the treatment of acute brain ischemia?
ABRAINI JH,1,2 DAVID HN,2 HAELEWYN B,2 RISSO JJ.3
1 ERT 1083 “Pharmacologie et Formulation de Gaz-Médicaments”, UMR 6232, Université de Caen, CNRS, CEA, Centre CYCERON, Caen, France; 2 NNOXe Pharmaceuticals, Quebec, Canada ; 3 IMNSSA, Toulon, France.
Background: As a general consensus, the noble and remarkably safe anesthetic gas xenon, which possesses low-affinity antagonistic properties at the NMDA receptor, has been clearly demonstrated as a promising preclinical neuroprotective agent for the treatment of acute cerebral ischemia (and other hypoxic-ischemic insults), with no proven adverse side effects when used at subanesthetic concentrations. However, surprisingly, possible interactions between xenon and tissue-type plasminogen activator (t-PA), a serine protease with thrombolytic activity that is the only drug approved for the treatment of acute brain ischemia, have never been investigated.

Methods: We review in vitro and in vivo unpublished and published structural, electrophysiological, electrochemical, biochemical, and pharmacological data on the mechanisms of action and the neuroprotective effects of xenon, and its interactions with t-PA.

Results: We show that xenon would produce its antagonistic action at the NMDA receptor by binding on a specific hydrophobic pocket that may be located on the NR1 subunit. In addition, we also show that xenon has exceptional neuroprotective properties that take place within a limited but interesting therapeutic window following ischemia onset. Finally, we show de novo that xenon at concentrations higher than 25 vol% reduces the thrombolytic and proteolytic properties of t PA both in vitro and in vivo in rats subjected to a thrombo-embolic model of middle cerebral artery by interacting directly with the catalytic site of t-PA.

Conclusions: Overall, these data indicate that xenon should be used for the treatment of acute ischemic stroke according to a well-defined therapeutic sequence. We propose that xenon at concentrations higher than 25 vol% should not be administered in patients suffering ischemia due to the risk of inhibiting the benefits of t-PA-induced thrombolysis or possible endogenous fibrinolysis in patients who cannot be treated with t PA. Then, once blood flow would be restored spontaneously or by t-PA, xenon could be used at higher subanesthetic doses, if necessary, to increase neuroprotection and to reduce the risk of adverse proteolytic side-effect of t PA therapy that is hemorrhaging.


Central Nervous Systems involvement in dogs naturally infected by Leishmania chagasi/infantum
ABREU-SILVA AL1,  DE  CARVALHO DA SILVA AP1, DE MACEDO AA1, DE CARVALHO NETA AV2,  AND DA SILVA CALABRESE K3
1Departamento de Patologia da Universidade Estadual do Maranhão, São Luís – Maranhão Brazil.,

2Departamento de Quimica e Biologia da Universidade Estadual do Maranhão, São Luís – Maranhão Brazil.,



3Laboratório de Imunomodulação, Departamento de Protozoologia do Instituto Oswaldo Cruz, Rio de Janeiro, Brazil.
Blood brain barrier (BBB) was described by Paul Ehrlich when he injected dyes in the blood stream and observed that all tissues stained, except the organs of central nervous system (CNS). This barrier is very efficient in controlling substances that could cause damage to the brain. However, several pathogens are able to cross it. In order to demonstrate that Leishmania chagasi/ infantum is also capable to produce lesions in CNS, the brain of thirty dogs naturally infected by the protozoan were studied. The samples were submitted to histopathological, imunohistochemical exams and Polimerase Chain Reaction (PCR). Histopathological analysis revealed that the amastigotes forms were associated to an inflammatory reaction. It was observed mainly in the cerebellum and thalamus. Both PCR and immunohistochemistry confirmed the presence of the parasite in 20% of the examined brains. Previous studies in our laboratory evidenced that mice experimentally infected by L. amazonensis also developed inflammatory infiltrates composed by eosinophils and parasitized macrophages. Mast cells were frequently observed. Both studies demonstrated that Leishmania is able to change the permeability of BBB leading to lesions. Although, the brain is considered a healthy place immunologically privileged several pathogens can cross this barrier and cause injury. Different hypotheses have been postulated to explain how the efficient BBB is impaired. In accordance to Persidsky et al. (2006), it occurs during inflammatory process due to disruption of junction complexes between brain microvascular endothelial cells with subsequent formation of a paracellular route that facilitates entry of leukocytes into cerebral parenchyma. We suppose that Leishmania reached brain of mice and canine through immature monocytes.


New Silver Compounds as Wound Healing Material Problems and Opportunities
ABU-YOUSSEF MA , GOHAR YB, ÖHRSTRÖM LC,D, LANGER VC, MASSOUD AA,C
aDepartment of Chemistry, Faculty of Science, Alexandria University, P.O. Box 426 Ibrahimia, 21321 Alexandria, EGYPT, bDepartment of Microbiology, Faculty of Science, Alexandria University, 21321 Alexandria, EGYPT, cDepartment of Chemical and Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, SWEDEN, dRebact, Stena Center 1C, 412 92 Göteborg, SWEDEN.

Wounds are a major medical problem affecting about 10% of all hospitalized patients and costing more than $5 billion US$ per year in the USA alone.1 The major problem, especially with large wounds, such as burns, and chronical wounds, is the risk of infection. And that this not a mere inconvenience, event today infected wounds may be lethal to hospitalized patients. The antibacterial properties of silver and its low toxicity, combined with the ease of topical applications and surface coatings using the metal and its compounds has led to a revival of silver use in medicine.2 Silver containing wound dressings are today based on mainly silver or simple silver salts such as the nitrate or the sulphate. The only silver coordination compound used to any extent is the [Ag(sulfadiazine)]n coordination polymer patented in 1973, a prescription drug in the US and sold under trade names such as Silvazine in preparations as a 1% cream.

In this contribution we will discuss some problems affecting different types of silver therapy, i.e. silver resistant bacteria (contrary to popular belief this does exist and may be a growing problem), coupling of silver and antibiotic resistance (remains to be proven, but a link exists), in vitro and in vivo studies (difficult to extrapolate and documented effect of existing preparations not always good).

We will also examine the opportunities that new coordination compounds may give in this respect and what grounds there are to expect that other species other than just the “naked” Ag+ ion could be the active antimicrobial agents. New silver complexes were synthesized by direct mixing of aqueous solutions of silver nitrate and ethanolic solutions of the corresponding ligand. Also solid state techniques were employed to synthesis [Ag(2-aminopyridine)3](NO3) and [Ag3(2-aminopyridine)4(NO3)2](NO3). Further synthesis and structural details are described elsewhere.3 UV- as well as 1H-NMR titrations were carried out to investigate the structural behavior and stability at different ratios. Antibacterial activity of the complexes was determined according to the recommendations of NCCLS (1999) for the use of a broth microdilution method. The activity (1/MIC) of some Ag(I) nicotinate and iso-nicotinate compounds compared to silversulfadiazine against some clinically isolated multi-resistant bacteria.3


1 J. E. Williamson, Dressing for success: New wound care products aid healing, efficiencies, Healthcare Purchasing News, Jan., 2005. 2 S. Silver, L. T. Phung, G. Silver, J Ind. Microbiol. Biotechnol., 2006, 33, 627–634. 3 M. A. M. Abu-Youssef, R. Dey, A. A. Massoud, Y. Gohar, V. Langer, L. Öhrström, Swedish Patent Application, 0701314-7, 2007; M. A. M. Abu-Youssef, R. Dey, A. A. Massoud, Y. Gohar, V. Langer, L. Öhrström, Inorg. Chem., 2007,5893; Morsy A. M. Abu-Youssef, Vratislav Langer and Lars Ohrstrom, Dalton Trans.,2006, 2542.


PKC-ι inhibition by ICA-1 reduces cell proliferation in Neuroblastoma
PILLAI P, DESAI S, WIN H, OSTROV D* AND ACEVEDO-DUNCAN M
Department of Chemistry, University of South Florida, Tampa, Fl

James A. Haley Veteran’s Hospital, Tampa, Fl



*University of Florida, Gainesville, Fl

Abstract
Neuroblastomas are highly lethal tumors and 85% of cerebral neuroblastoma occurs in children and 15% in adults. Neuroblastoma is the fourth most common type of cancer in children. According to the American Cancer Society, there are approximately 650 new cases of neuroblastoma each year in the United States. Despite significant educational efforts, improved diagnostic techniques, and rigorous therapies, neuroblastoma control remains static. To address this health issue, the objectives of this research was to investigate the use protein kinase C-iota (PKC- ι) inhibitors on the proliferation of neuroblastoma cells. Previous work has shown that inhibition of PKC- ι is a promising means by which to prevent and treat certain cancers. Here, we report the identification of a PKC- ι inhibitor (1H-imidazole-4-carboxamide, 5-amino-1-[2,3-dihydroxy-4-[(phosphonooxy) methyl] cyclopentyl]-,[1R-(1α, 2β, 3 β, 4 α)] (ICA-1) that targets a unique sequence (amino acid residues 469-475) in the catalytic domain of PKC- inhibits PKC- ι activity and is effective in blocking the proliferation of BE(2)-C neuroblastoma cells. Our data support significant proof of concept that ICA-1 inhibits the proliferation of neuroblastoma cells and may be a novel chemotherapeutic for the treatment of patients with neuroblastoma.





Generation of Human Gene Knockout Cell Lines: Application to Assessment of Genotoxic Anticancer Drugs
ADACHI N
International Graduate School of Arts and Sciences, Yokohama City University, Yokohama, Japan.
Background: DNA damage causes cancer, is used to treat cancer, and is responsible for many of the side effects of cancer therapies. It is thus important to understand how chemotherapeutic agents cause DNA damage and how cells cope with such damage, particularly in the context of human somatic cells. Many of chemotherapeutic agents currently used in the clinic target DNA topoisomerases; for example, camptothecin is a topoisomerase I inhibitor, while etoposide a topoisomerase II inhibitor. These agents, like ionizing radiation, have been shown to induce DNA double-strand breaks (DSBs), but clearly by distinct mechanisms. In human somatic cells, the roles of two major DSB repair pathways, homologous recombination (HR) and nonhomologous end-joining (NHEJ), in the repair of topoisomerase-induced DNA damage are not completely understood.

Methods: We have recently developed a system using the human pre-B cell line Nalm-6 that enables rapid production of knockout cell lines. Using this system, we generated human cell lines deficient for Rad54, a HR protein, and/or DNA ligase IV (Lig4), a critical NHEJ ligase. Cells lacking Artemis, a nuclease involved in NHEJ, were also created by gene targeting using Nalm-6. Sensitivity assays were performed by clonogenic survival assays or by using the CellTiter-Glo Luminescent Viability Assay kit (Promega).

Results: We find that NHEJ is critical for repairing topoisomerase II- as well as low-dose irradiation-induced DNA damage, while HR is important for repairing topoisomerase I-induced DNA damage. Intriguingly, NHEJ negatively affects survival of cells treated with the topoisomerase I poison camptothecin. We also find that loss of Artemis not only leads to increased camptothecin resistance, independently of Lig4, but also alleviates hypersensitivity of Lig4-null cells to topoisomerase II inhibitors.

Conclusions: 1) HR and NHEJ have different roles in the repair of topoisomerase-mediated DNA damage. 2) Our data have significant implications for chemotherapy involving topoisomerase inhibitors. 3) A series of human gene knockout cell lines are useful in assessing cellular DNA damage and repair induced by chemotherapeutic agents.


Magic Bullets against the Autoimmune Diseases
ADAMS DD
University of Otago Medical School, Dunedin, New Zealand
Abstract
In 1908 Paul Ehrlich was awarded the Nobel Prize for discovering Salvarsan, a “magic bullet” that was more toxic for the spirochaete of syphilis than for man, and for showing that immune reactivity against host components did not normally occur but, as an abnormality, could be the basis of many disease processes. Today, knowledge of the autoimmune diseases has reached the stage of showing how they can be cured by “magic bullets” against the forbidden clones of B and T lymphocytes that cause them. The magic bullets can be made by isolating the target autoantigen and coupling it to a cytotoxic moiety, such as bungarotoxin or a molecule containing a radioactive element such as 131Iodine emitting short-range radioactivity in the form of beta particles (electrons). Such therapeutic molecules, administered intravenously, would home cytotoxically on the lymphocytes of the pathogenic forbidden clones, selectively destroying them. The autoantigen for rheumatoid arthritis, calpastatin, is already available for use in this way, and so is that for the probably autoimmune lethal stage of HIV infection, AIDS, in the form of the CD4 structure on helper T lymphocytes. Additionally, dangerously severe autoimmune diseases can be cured by chemical or radiological generalised immune ablation, which will destroy the forbidden clones, followed by immune restitution with autologous stem cells, taken previously from the patient’s own bone marrow. Because unlucky semi-random somatic mutations in immunoglobulin variable region (V) genes are responsible for occurrence of the pathogenic forbidden clones, they are unlikely to recur in the regenerated immune system (Burnet’s Forbidden Clone Theory) and this has been demonstrated therapeutically in cases of severe scleroderma.


Nicotinamide Mechanisms of Neuroprotection in Stroke
ADAMS JD
University of Southern California, School of Pharmacy, Los Angeles, CA, USA
Background: Stroke is a major cause of death in the USA. Although stroke can be treated by removing intracerebral clots or by administration of clot dissolving agents, therapy for stroke is inadequate. Patients frequently do not recover normal speech or motion following strokes. The current work explores the development of a new therapeutic agent, nicotinamide, for recovery from stroke.

Methods: The focal ischemia and reperfusion model of stroke in rats was used, as well as the global ischemia and reperfusion model in mice. Mechanistic experiments were performed with intracerebroventricular t-butylhydroperoxide treated mice. Nicotinamide was adminstered at various doses and various times before or after ischemia and reperfusion. Brain cell damage was examined by light and electron microscopy. The brain levels of pyridine dinucleotides, glutathione and ATP were measured. DNA fragmentation and poly(ADP-ribose) polymerase activity were assessed.

Results: Mechanistic studies show that glutathione is oxidized, NAD and ATP levels decrease during oxidative stress in the brain. Poly(ADP-ribose) polymerase is activated and DNA fragmentation occurrs during oxidative stress. Ischemia and reperfusion result in a central necrotic core surrounded by a limit that includes apoptotic cells. Nicotinamide used as a pretreatment or post-treatment is able to prevent both necrosis and apoptosis in the brain suffering from ischemia and reperfusion. Nicotinamide is partially effective even when given 6 hours after reperfusion. Nicotinamide increases brain NAD and ATP levels and regulates poly(ADP-ribose) polymerase activity.

Conclusions: Nicotinamide is an effective and safe neuroprotective agent. The mechanism of nicotinamide neuroprotection involves inhibition of poly(ADP-ribose) polymerase and stimulation of NAD synthesis. Poly(ADP-ribose) polymerase regulates the activities of a number of enzymes and genes. These results will be discussed in terms of caspase activation and the induction of IAPs.
Author’s disclosure statement: The author is part owner of the US patent for the use of nicotinamide as a neuroprotective agent in stroke and other conditions.



Prevention of Mucositis and Improvement in Compliance of Head & Neck Cancer Patients undergoing Radio-Chemotherapy by Curcumin
ADHVARYU MR1, VAKHARIA BC2, REDDY MN1, SRIVASTAV SP3
1Veer Narmad South Gujarat University, Surat, India; 2Shree Gurudev Sarvajanik Charitable trust, Surat, India; 3Lions Cancer Research Center, Surat, India.
Background: Oral mucositis (OM) is a common complication and a dose limiting toxicity in up to 90% of head & neck cancer patients (HNCP) undergoing radio-chemotherapy (RCT). Its adverse effects on schedule of therapy, quality of life and economic burden to the patients and system warrant an urgent need for a potent cell specific radioprotector. Several adjuvant agents like folic acid, Vit-E, antibiotic mouth rinse etc have been tried to prevent OM without remarkable success. Curcumin has shown radioprotective as well as radiosensitizing potential in in vitro studies with its antioxidant, free radical scavenging activity and ability to arrest cell cycle in G2 and M phase in malignant cells. Objective of this pilot study was to evaluate effects of curcumin on OM in HNCP under going RCT.

Methods: 95 HNCPs were given conventional RCT and 109 HNCP were given 2 gm of curcumin/day orally in 3 divided doses in addition to RCT for two months starting from 3 days before planned radiation. OM gradation as per WHO oral toxicity scale was done weekly for the whole RCT period and follow-up was continued for 6 months in both the groups. Incidence, onset and duration of OM in each grade, and patient compliance in term of uninterrupted completion of scheduled RCT were compared in both controlled and curcumin treated group by Chi-square test (P≤ 0.05).

Results: There was a significant decrease in incidence of grade III and IV OM (P≤ 0.001) among curcumin treated group. Patient compliance in terms of completion of scheduled RCT increased from 53% to 89.0% (P ≤ 0.001).

Conclusion: 1. Curcumin showed a significant adjuvant protective activity against RCT induced OM in HNCP 2. Long term follow-up required for its effects on recurrence and survival in HNCP.




Preparation and Evaluation of Mucinated Sodium Alginate Microparticles for Oral Delivery of Insulin
ADIKWU MU1, BUILDERS FP2
1Department of Pharmaceutics, University of Nigeria, 410001 Nsukka, Nigeria; 2Department of Pharmaceutical Technology and Raw Material Development,

National Institute for Pharmaceutical Research and Development, Abuja, Nigeria


Background: Effective oral insulin delivery remains a challenge to the pharmaceutical industry. A novel formulation of insulin using new biomaterials is necessary to formulate and administer insulin via the oral route. Aims: 1) To develop new biocompatible delivery materials through cross-linking for the delivery of insulin. 2) To study the level of protection of insulin against degradation when formulated using the new biomaterial. 3) To study the in vitro and in vivo release of the insulin and its effect on blood glucose level in diabetic rabbits.

Methods: Cross-linking of mucin-sodium alginate of ratios 0:1 to 1:3 was effected in liquid paraffin using acetone at -30 oC. The microparticles were diffusion-filled and further coated with 1.5 % w/v cellulose acetate phthalate in acetone at -30 oC. Diabetes was induced in 32 rabbits weighing between 1.8-2.5 kg using 120 mg/kg of alloxan and these used for the anti-diabetic assessment. Insulin-loaded microparticles containing 50 IU/kg was given to the rabbits in 2 ml of distilled water using gastric intubation using distilled water as the negative control and 50 IU/kg subcutaneously as the positive control.

Results: The microparticles formed were generally multi-particulate, discrete and free flowing. Before insulin loading, microparticles were round and smooth, becoming fluffier, less spherical and larger with rough and pitted surface after insulin loading. The mean dissolution time of insulin from the microparticles prepared with sodium alginate, mucin, sodium alginate: mucin ratios of 1:1, 3:1 and 1:3 were 11.21±0.75, 3.3±0.42, 6.69±023, 8.52±0.95 and 3.48±0.65 (min) respectively. The percentage blood glucose reduction for the subcutaneously administered insulin was significantly (p < 0.001) higher than for the formulations. The blood glucose reduction effect produced by the orally administered insulin-loaded microparticles prepared with 3 parts of sodium alginate and 1 part of mucin after 5 h was, however, equal to that produced by the subcutaneously administered insulin solution.

Conclusion: This study shows that the oral route could be an effective alternative for the delivery of insulin using this polymer cross-link.


Trends in Co-Occuring Diseases in Patients Treated for Alcohol and Drug Problems in Canada.
ADRIAN M
Nova Southeastern University, Ft. Lauderdale, FL, USA
Background: Understanding the disease experience of alcohol and drug patients (AD) is needed for rational decision-making in health care and disease prevention. Aim: 1) To improve measurement of co-occurring disease (co-morbidity) in AD patients using population-based data 2) to easily identify reduced co-morbidity using a new more sensitive measure.

Method: Co-morbidity was measured using the standardized morbidity ratio (MR), comparing 1985-86 Hospital Medical Records Institute data for all inpatient cases(n=52,200) with primary (P) or secondary (S) alcohol or drug diagnoses in all Ontario hospitals to data for all patients in all Canadian hospitals, using indirect age-sex standardization and adjusting for multiple diagnoses. The modified MR (mMR) was used to improve measurement and visual display (graphing) of reduced co-morbidities.

Results: Compared to all patients, AD patients had more co-morbidity. Generally, MR was higher in patients with primary (P) rather than secondary (S) AD diagnoses Patients treated for the use or misuse of prescription drugs had the highest MR (MRP=13.3 and MRS=3.5). MR was intermediate for patients who used illegal drugs (MRP=8.9 and MRS=4.7), and lower for alcohol patients (MRP=6.7 and MRS =4.1). Co-morbidity in alcohol patients stemmed from practically all diagnostic categories, but co-morbidities in drug patients were due to fewer diagnostic categories. AD patients had particularly high MR for mental disorders, infections and parasitic conditions, and injuries and poisonings. Cocaine cases had high MR for infectious and parasitic diseases, and diseases of the skin and subcutaneous tissue. Amphetamine cases had high MR for diseases of the digestive system, and of the musculoskeletal system and connective tissue. Graphing results using the mMR clearly show AD patients had reduced co-morbidity from complications of pregnancy, childbirth and the puerperium, and from conditions originating in the perinatal period, but a higher rate of congenital anomalies.

Conclusion: 1) AD patients had more co-morbidity than all patients combined, with co-morbidity involving more diagnostic categories for alcohol than drug patients, but they had less co-morbidity related to reproduction than all patients. 2) mMR is a sensitive measure of reduced co-morbidity.


TOPICAL IMMUNOTHERAPY WITH DIPHENYLCYCLOPOPENONE IN VITILIGO: A PRELIMINARY EXPERIENCE
AGHAEI S, MD1, SAFAEE-ARDEKANI GR, MD2
1- Jahrom University of Medical Sciences, School of Medicine, Jahrom, Iran

2- Shiraz University of Medical Sciences, School of Medicine, Shiraz, Iran


Background: Despite recent significant therapeutic advances, vitiligo remains as a clinical conundrum. Topical immunotherapy has been extensively tested in the treatment of various dermatologic disorders especially those believed to have an immunologic basis. The aim of this study was to evaluate the role of topical DPCP in the treatment of vitiligo.

Methods: Nineteen patients with limited vitiligo lesions were enrolled in this study. After sensitization with 2% DPCP, progressively higher concentrations beginning at 0.001% were applied weekly for 6 months to depigmented skin. The maximum concentration of DPCP in acetone was 2%.

Results: Thirteen of 19 patients were evaluated at the end of 6 months. Four patients with focal vitiligo, 3 patients with vitiligo vulgaris, and 3 patients with segmental vitiligo showed marked (grade 3) repigmentation.

Conclusion: Marginal and central repigmentation with hyperpigmented borders was seen in the majority of lesions. Further controlled trials should be undertaken to evaluate the use of topical DPCP in vitiligo, as this preliminary study is encouraging.


Studies on Interactions of Water Soluble Vitamins with Zinc Through cell, Protein and Animal Models in Health and Disease
TUPE RS and AGTE VV
Agharkar Research Institute, G.G. Agarkar Road, Pune 411004, India
Background: Zinc (Zn) is required as a catalytic, structural and regulatory ion for enzymes, proteins and transcription factors and is thus a key trace element in many homeostatic mechanisms of the body. Vitamins like riboflavin, nicotinic acid, thiamine, folic acid and ascorbic acid have functional groups capable of forming complexes with Zn. However, the interaction of water-soluble vitamins with Zn has not received much attention.

Methods: We have examined the Zn-vitamin interactions at a variety of conditions like different Zn concentrations, different cell and protein models and under normal and oxidative stress (OS) conditions. The interactions were studied in vitro, by using erythrocytes under deficient, normal and excess Zn states.

Results: Under Zn-deficient state, thiamine significantly enhanced the erythrocyte Zn uptakes (p<0.05), whereas ascorbic acid and riboflavin inhibited it (p<0.05). In another study, an in vitro erythrocyte Zn uptake was compared among healthy and diabetic subjects and it was found that Zn uptakes of healthy subjects were 17-52% higher than those for diabetic subjects. Furthermore, erythrocyte super oxide dismutase, plasma ascorbic acid and status of riboflavin were negatively correlated with Zn uptakes in healthy subjects (p<0.01). These interactions were also studied in precision cut rat liver slices, where it was found that folic acid showed inhibitory effect on Zn uptake under both normal and OS conditions as seen by dose response curves. Ascorbic acid showed marked enhancing effect on Zn uptake under OS. These in vitro interactions were confirmed in vivo using male Wistar rats. The 21 days old rats were used to examine the effect of niacin supplementation on Zn absorption under chronic OS generated by tert-butyl hydro peroxide at a dose of 0.2 mM/Kg body weight. Niacin supplementation increased the Zn absorption and improved antioxidant enzyme profile. The albumin being the major Zn carrier protein in plasma and the albumin bound Zn (ABZn) comprises 80% plasma Zn. Folic acid and thiamine significantly enhanced the ABZn (p<0.010), while nicotinic acid inhibited Zn binding to albumin.

Conclusions: These results collectively suggest that vitamins are playing an important role in distribution of circulating Zn among albumin, blood cells and liver and giving a new dimension to their functionality in Zn metabolism in health and disease conditions.





Association of Fluoroquinolone and ESBL-Resistance in Gram-Negative Organisms from Oncology Patients of Lagos University Teaching Hospital (LUTH), Nigeria
AIBINU, IE, ADENIPEKUN, EO, NWAKA, DUC, ADELOWOTAN, AO, AJEKIGBE, AT. ADEYEMI, OF AND ODUGBEMI, TOLU
College Of Medicine, University Of Lagos. Nigeria
Background: This study determined the gram-negative bacilli associated with various cancer infections and defined fluoroquinolone susceptibility and Extended-Spectrum Beta-Lactamase production in isolated strains.

Methods: Materials for research were blood culture, urine, aspirates, fluids and swabs from cancer wounds. Samples were cultured and organisms isolated were determined using API system (Bio-Merieux). Antimicrobial resistance was estimated by the disc diffusion method according to NCCLS/CLSI recommendations and ESBL detection was carried out using the Double Disk Synergy Test method

Result: Of the 103 strains isolated 22 (21.4%) were found to be resistant to only ciprofloxacin. Only 1 of these resistances to ciprofloxacin was observed to have an accompanying production of ESBL. Of the 7 isolates that had resistance to a combination of two fluoroquinolones, 2 (28.6%) were found to be ESBL-producers. Cross resistance to the 3 quinolones tested, occurred in 40 (38.8%) of the strains isolated. The strains in this group were observed to be associated in most of the cases with MDR [35 (37.5%)] and production of ESBL [16(41%)]. This group was observed to be predominant amongst strains of E.coli, Pseudomonas spp and Klebsiella spp.

Conclusion: Cross-resistance to fluoroquinolones has emerged amongst these clinical isolates and more worrisome is its association with ESBL-Production and Multidrug Resistance. Multi-drug resistance may be one of the contributing factors to the high mortality rate amongst these group of patients reported in developing countries. Antibiotic resistance surveillance is thus of utmost importance in contributing to the reduction of the high morbidity and mortality rate reported amongst cancer patients in this part of the world.


Clinical Applications of Ghrelin
AKAMIZU T1, IWAKURA H1, ARIYASU H1, KANGAWA K1,2
1 Kyoto University, Kyoto, JAPAN; 2 National Cardiovascular Center, Suita, JAPAn.
Background: Ghrelin is a 28-amino-acid peptide hormone that was discovered in 1999 as an endogenous ligand for the growth hormone (GH)-secretagogue receptor (GHS-R). Ghrelin plays a critical role in a variety of physiological processes including stimulation of GH secretion and food. These actions of ghrelin should be invaluable for the development of novel treatments and disease diagnostic techniques.

Methods: Study 1: we attempted to evaluate the clinical response to repeated ghrelin administration in patients with anorexia caused by functional disorders. Subjects were included in this study, who 1) are diagnosed with functional anorexia, 2) are lean, and 3) exhibit decreased FI. Subjects received an intravenous infusion of 3 microg/kg ghrelin for thirty minutes twice a day for two weeks. We investigated the effects of ghrelin administration on food intake (FI), appetite, hormones, and metabolic parameters. Study 2: we evaluated the effects of ghrelin administration on physical performance and body composition in patients undergoing elective total hip replacement (THR) as treatment for osteoarthritis (OA). Thirty-two patients were assigned to two groups of sixteen subjects each; the ghrelin group received intravenous injections of 2 microg/kg ghrelin, while the placebo group received vehicle alone. Subjects received twice daily injections for three weeks beginning one week before surgery.

Results: Study 1: Ghrelin administration tended to increase daily FI in comparison to levels before and after completion of treatment, although this difference that was the primary endpoint of this study did not reach statistical significance. Hunger sensation was significantly elevated at the end of drip infusion. Study 2: While ghrelin significantly increased lean body mass after the three-week injection period, it did not affect muscle strength or walking ability. Significant decreases in fat mass and GH responses to ghrelin injection were also observed.

Conclusions: Ghrelin treatment has stimulatory effects on appetite in patients with functional anorexia. On the other hand, ghrelin administration did not provide any favorable effect on physical performance in patients with OA undergoing THR, despite increased lean tissue reserves. Further studies remain necessary to confirm the efficacy of ghrelin treatment for anorexia- and catabolism/aging-related disorders.



Effect of Diabetes Mellitus on Pharmacokinetics (PK) and Pharmacodynamics (PD) of Immunosuppressive agents: Ciclosporin, Tacrolimus and Mycophenolic Acid
AKHLAGHI F1, CHITNIS SD1, MENDONZA AE1, PATEL CG1, GOHH RY2
1Clinical Pharmacokinetics Research Laboratory, Uni. of Rhode Island, Kingston, RI, USA; 2Division of Transplantation, Brown Uni. Medical School, Providence, RI, USA.
Background: A large percentage of kidney transplant recipients are diabetics but little is known on the effect of diabetes on the disposition or effect of immunosuppressive agents.

Methods: The PK and PD studies included 42 and 32 stable kidney transplants, sampled for 12 or 2 hours post dose, respectively. Approximately 50% of patients were diabetic (D) that were demographically matched with non-diabetic (ND) controls. Immunosuppressive agents’ total, unbound and metabolite concentrations were measured by LC-MS/MS. Markers of T-cell activity (ATP concentration in CD4 cells, intracellular cytokines IL-2, IFN- and TNF- in CD3 cells) and B-cell activity (co-stimulatory proteins CD54 [ICAM-1], CD86 [B7.2] and CD95 [Fas antigen] in stimulated CD19) were determined. Inosine monophosphate dehydrogenase (IMPDH) activity was also measured in some patients.

Results: Pharmacokinetics: As summarized in the Table, both ciclosporin (CsA) Cmax and AUC was reduced in Ds and CsA free fraction was higher. Tacrolimus absorption was delayed with no effect on the overall AUC. Diabetes delayed mycophenolate mofetil (MMF) absorption rate but not the enteric coated Na-MPA. The concentration of some metabolites of ciclosporin or MPA was lower in Ds.

Pharmacodynamics: The mean ± SD of ATP concentration was 298 ± 78 ng/mL in D and 359 ± 86 in ND patients (P=0.021). Expression of intracellular IL-2 in CD3 cells was lower in D (mean florescence intensity: D 104 ± 42, ND 145 ± 74; P=0.03). Also CD95 cell surface expression on B-cells was lower in Ds (D: 73 ± 28 ND: 114 ± 68; P=0.01) however despite a trend, expression of CD54 or CD86 did not differ. IMPDH activity was 17.5  2.8 vs. 46.6  2.5 nmol XMP/h/µgprotein, in D and ND, respectively (P<0.0001).

Conclusions: Diabetes variably affect the PK/PD of immunosuppressive agents. Adjusting immunosuppressive dose guided by the PD markers may prove useful in dose individualization of immunosuppressive agents in diabetics.




Chemotherapy of advanced colorectal carcinoma under hemodialysis
AKIYAMA S, TANAKA M
Mitsukaido Sakura Hospital, Mitsukaido, IB, Japan.
Background: Recent progress of hemodialysis therapy (HD) has prolonged the life span of patients sufferring from end stage renal disease (ESRD) and it increased the complication of malignant tumors. It is reported that the prevalence of colorectal cancer in HD patients is higher than that in a control population. Saltz regimen; combination therapy of irinotecan, 5-fluorouracil, and leucovorin is widely used for the treatment of metastatic colorectal cancer after the large randomized phase III trials. Chemotherapy of HD patients is difficult because there are few pharmacokinetic data of most cytotoxic agents much less combination chemotherapy. We encountered a patient of colorectal carcinoma on HD. It was decided to give combination chemotherapy with monitoring the pharmacokinetics of the patient.

Methods: CPT-11 was administered just after HD at a dose of 50 mg/m2 by 90-min intravenous infusion; followed by l-LV 10 mg/m2, administered over the course of 15min; and 5-FU (400 mg/m2), given by bolus intravenous injection after l-LV. Three drugs were given on days 1, 8 and 15 of a 35-day cycle. Blood samples were collected before administration and at 0.5, 4, 12, 24 hours after administration. Plasma concentration of CPT-11, SN-38 and 5-FU were compared to those in reference control values without ESRD. The plasma concentration of CPT-11, SN-38 and 5-FU were analyzed using high performance-liquid chromatography (HPLC).

Results: The pharmacokinetic results for each post administration value were not statistically different compared with the data of normal renal function. As for side effects, he experienced grade III hematological toxicity, which was easily controlled with G-CSF.
Time after administration (hrs) 0 0.5 4 12 24

CPT-11 (ng/ml) 0 820-845 610-790 340 95

SN-38   (ng/ml) 0 8.4-12.0 7.5-8.2 5.2 4.4

5-FU   (ng/ml) 0 7,200-12,300 0 0 0


Conclusions: These data suggest that Saltz regimen can be feasible for colorectal cancer patients receiving HD without dose reducing




In vitro Activities of Extracts from Naturals Plants on the Human Filaria Loa loa
MENGOME LE1, FEUYA TCHOUYA GR1, SOUZA A1, NSI EMVO E1, AKUE JP2
1 Institut de Pharmacopée et de Médecine Traditionnelle (IPHAMETRA), Libreville, Gabon;

2 Centre International de Recherches Médicales de Franceville (CIRMF), Franceville , Gabon.
Background: Loa loa is a human filaria endemic to West Africa. Current drugs such as Diethylcarbamazine (DEC) and Ivermectin induce severe adverse reactions like encephalitis and patient death in high microfilaremic individuals. Therefore there is a need for new drugs. Plants are known as potential nematocids, but no study has been carried out to examine their effect on Loa loa. Aim: to screen nematocidal plants used in traditional medicine for their filaricidal activity.

Methods: Plants were collected according to their traditional usage an identified using botanic criteria. Extracts were obtained by using different organic solvents (Dichloromethane, Methanol, Water). The resulting products were dissolved at 1mg/ml in Dimethylsulfoxid (DMSO). Co cultures of extract and filaria were made in duplicate using a 96 well cell culture plaque containing LLCMK2 cells, MEM medium with 10% Fetal calf serum and antibiotics. 5 Loa loa microfilaria were added in each well and plaques were incubated at 37°C in 5% CO2 atmosphere for 120 hours. The effects of plant extracts were measured by observing the motility and mobility of filaria in wells containing different concentrations of extract compared to negative controls (no extract or drug in the well) and positive controls (DEC or Ivermectin in the well ) at different concentrations.

Results: Extracts from seven plants species of the Euphorbiaceae, Caesalpiniacae, Compositeae, Mimosaceae, Ochnaceae, Rutaceae, Annonaceae family had microfilaricidal activity at concentrations of 95.6µg and 47.8µg, while plants from Lecytidaceae had no effects on filaria at these concentrations.

Conclusion: Crude extracts of some plants used in traditional medicine have in vitro effect on the human filaria Loa loa.


The Role of Ancient Iraqi People (Sumerian, Assyrian, Babylonian and Arabian) in the Development of Medicine as Viewed by Western Writers
AL MOSAWI AJ
University Hospital in Al Kadhimiyia,Baghdad,Iraq.
Background: The region of Iraq was historically known as Mesopotamia and was home to the world's first known civilizations These civilizations produced some of the earliest writing and some of the first sciences and medicine of the world; hence its common epithet, the "Cradle of Civilization". The aim of this paper is to study the views of the distinguished western writers regarding the role of ancient people of Iraq in the development of Medicine.

Methods: the views of the distinguished western writers regarding the role of ancient people of Iraq in the development of Medicine were reviewed and studied.

Results: Samuel Noah Kramer considered the considered the Sumerian pharmacological tablets as the first pharmacopoeia. In summarizing the effects of Arabian in the development of medicine Stubb and Bleight stated in 1931”With Arabs began the real craft of apothecaries”. Meyerhof in 1944 wrote in his book “Pharmacology during the golden age of Arabian Medicine” “The establishment of hospitals was originated by Arabians”

Conclusions: The ancient Iraqi people played an important role in the early development of medicine.


Retargeting anticancer drugs to drug resistant cancers by using polymer Biotransport technology. Clinical proof of the concept
ALAKHOV VY
Suptarek Pharma Inc.,Montreal, Canada
Background: Anthracyclines are amongst the most widely used anticancer agents in man, but are limited by toxicity considerations, as well as by inherent or induced drug resistance. We have recently discovered that nonionic block copolymeric surfactants, i.e. hydrophobic polyethylene oxide polypropylene oxide block copolymers (Pluronics) can considerably reduce drug resistance of various tumour cells to anthracyclines and other cytotoxic drugs. Following this finding, we have developed a Pluronic-based formulation of doxorubicin (SP1049C) that is thermodynamically stable, safe and provides doxorubicin with high efficacy against both drug resistant and drug sensitive tumours.

Methods: Safety and plasma pharmacokinetics of SP1049C were evaluated in phase I clinical trial that was curried out in 26 advanced cancer patients; and efficacy of the product was tested in phase II clinical trial, in 21 patients with metastatic adenocarcinoma of the esophagus.

Results: The results of phase I trial demonstrated comparable safety and PK profiles of SP1049C to that of doxorubicin. The phase II trial revealed that the product has a high anticancer activity. The overall responce rate to SP1049C was 47%, (95% CI: 24 -71), and medial survival was 10 months, which compares favourably with other most active single agents tasted in this indication.

Conclusions: The performed clinical studies have assuared a further clinical development of SP1049C. At present it is entering an expanded international clinical phase II/III efficacy program including a single 300 patient pivotal phase III trial in patients with upper gastrointestinal tract.


Novel reporter probes for HSV1-tk gene expression
ALAUDDIN MM
Center for Advanced Biomedical Imaging Research (CABIR), The University of Texas M D Anderson Cancer center, Houston, TX, USA.
Herpes simplex virus type-1 thymidine kinase (HSV1-tk) gene is being used as a suicide gene for gene therapy of cancer. Cancer cells are transduced with a retroviral vector carrying HSV1-tk gene. The gene expressed in the proliferating cells produces the HSV1-Tk enzyme that selectively phosphorylates a guanosine derivative, ganciclovir, to its monophosphate. The ganciclovir monophosphate is then converted to its di-phosphate form by the cellular kinases and/or HSV1-TK, and finally to the triphosphate form by cellular kinases. The ganciclovir tri-phosphate becomes a pro-drug and inhibits DNA polymerase, thus kills the tumor cells.

Malignant tumors have been successfully treated in animal models with suicide gene therapy using HSV1-tk gene and ganciclovir. However, clinical results with this method showed that gene delivery to the tumor cell in human was not sufficient. Therefore, an in vivo method to assess the HSV1-TK enzyme activity after gene transfer is required for the optimization of gene delivery and establishment of treatment efficacy. Positron emission tomography (PET) is a non-invasive modality for in vivo imaging of HSV1-tk gene expression using reporter gene and reporter probe, and can provide repeated and quantitative assessment of the expression of genes in tissues and organs.

Non-invasive imaging of transgene expression involves the appropriate combination of a reporter gene and a reporter probe. Model systems have been established and validated by HSV1-tk gene as a reporter gene, and radiolabeled pyrimidine nucleoside and acycloguanosine analogues as reporter probes. Reporter probes can be used (i) to image vector targeting and level of HSV1-tk expression, (ii) to image the regulation of endogenous genes and signal-transduction pathways; and (iii) to monitor and quantitatively assess the expression of a second transgene that is cis-linked to the reporter gene by an internal ribosome entry site sequence.

Various radiolableld reporter probes have been developed during the past decade, and these are primarily purine and pyrimidine nucleoside analogues, such as 18F-FHPG, 18F-FHBG, 18F-FMAU, 18F-FIAU, 18F-FEAU, 18F-FFAU etc., and also radioiodinated analogues of FIAU. Among these probes, 18F-FHBG, 18F-FIAU and 18F-FEAU have been studies extensively. 18F-FHBG and 18F-FEAU have been recognized as ideal probes for PET imaging of HSV1-tk gene expression. We have studies these probes in the animal models and demonstrated that both 18F-FHBG and 18F-FEAU have efficacy for imaging of HSV1-tk gene expression, and they can be used selectively in PET imaging of native and mutated HSV1-tk gene expression. Thus 18F-FEAU is suitable for PET imaging of the native HSV1-tk gene expression; and 18F-FHBG is suitable for PET imaging of mutated HSV1-tk gene expression. This presentation will focus on these novel probes used for PET imaging of HSV1-tk gene expression with an emphasis on their application in pre-clinical animal models and human studies.




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