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Immunomodulation by Antibacterial
Agents: Interference with Phagocyte Functions The possibility that antibacterial agents, primarily directed against microorganisms, also modify host functions is widely recognized. The immune system may contribute to therapeutic efficacy in infectious diseases. The immune system itself is a complex pyramid of redundant cellular factors: humoral effectors: mediators, whose fine regulation is just beginning to be unraveled. Phagocytes, ubiquitous and multifaceted cells are key components of cellular immunity, being involved both in immediate defenses against non-self targets (pathogens, tumor cells, exogenous molecules, etc.) and in the regulation and triggering of specific immune responses. They are thus, prime targets of immune response modifiers. This review reconsiders the widely explored problem of interactions between antibacterial agents and phagocytes, focusing on future prospects in both infectious and non-infectious diseases. ________________________________________ New Antimicrobial
Agents With the problem of emerging of bacterial resistance, pharmaceutical industry is showing a revived interest in developing new antibiotics. Use of old antimicrobial agents that were discontinued, combination antibiotic therapy, and maximizing the usual doses have failed to overcome the problem of bacterial resistance. Till recently, new antibiotics were only made by structural modification of existing antibiotic classes. For example, thousand of quiniolones have been in the research; but only few reached the clinical trial phase and very few have been approved; yet some were withdrawn from the market. Synercid, a new antibiotic that was approved recently failed to play a major role. Linezolid belongs to a new class of antibiotics (oxazolidinone) was approved recently but its role is still to be determined. Telithromycin (a new ketolide) was approved mainly for upper respiratory tract infection. Cefditoren (a new oral cephalosporin) and ertapenem (carbapenem) were introduced recently and may be "me too" products. Daptomycin, faropenem, tigecycline, oritavancin…. etc. will be reviewed. Activity, efficacy, of new antibiotics that were introduced recently will be discussed. ________________________________________ In Vitro Sensitivity
of Madurella mycetomatis ________________________________________ Production of New
Antimicrobial Agents from Twenty eight isolates of thermophilic bacteria were isolated and identified from recreational thermal springs located along the Jordan rift Valley. All isolates that were strictly aerobic microorganisms were further supported by the presence of carbohydrate fermentations, citrate utilization and the absence of catalase activity. They were tested for the ability to inhibit the growth of 6 test organisms, i.e. Klebsiella pneumoniae, Candida albicans, Staphylococcus aureus, Psuedomonas aeruginosa, Enterobacter sp, and Escherichia coli by agar-deferred spot method. It was found that 5 isolates were capable to inhibit the growth of test organisms, these stains are Yersinia sp, Serratia sp., Chryseomonas luteola, Aeromonas hydrophila and Hafnia alvei. The highest inhibition zone of all test organisms was observed with Staphylococcus aureus (19mm), followed by Candida albicans (18mm), Escherchia coli (16mm) and Pseudomonas aeruginosa (16mm). Partial purification of the antimicrobial agents by thin layer chromatography gave one inhibitory bands with Rf values as follows: 0.25 for Yersinia sp.l, 0.32 for Serratia sp.l , 024 for Chryseomonas luteola, 0.22 for Aeromonas hydrophila and 0.27 for Hafnia alvei. ________________________________________ Nosocomial Fungemia
among Intensive Care Units' Patients: Identification, Susceptibility
to Antifungal Agents and Risk Factors. Faculty of Medicine, Zagazig University, Zagazig,
Egypt This work was done to determine the incidence of nosocomial fungemia among Intensive Care Units' (ICUs) patients of Zagazig University Hospitals, to identify incriminated fungi and their antifungal susceptibility and to conclude fungemia risk factors. Between April 1999-April 2001 a prospective surveillance of cases of nosocomial fungemia was done. Identification of yeasts and molds was carried out by morphological studies. Yeasts were further identified biochemically by the Yeast Biochemical Cards (YBC)) using the automated Vitek-JR Apparatus. Broth microdilution method was used to determine minimal inhibitory concentration (MIC) of fungal isolates by amphotericine B, fluconazole, itraconazole and ketoconazole. Then a case-control study was conducted where risk factors were analyzed using multivariate logistic regression model. The overall rate of nosocomial fungemia was 15.08% [21.8% in the Neonatal Intensive Care Unit (NICU), 25.88% in the Pediatric Hematology unit (PHU), 26.08% in the Oncology unit (OU) and 5.9% in the Surgical Intensive Care Unit (SICU) ]. Candida albicans predominated all fungal pathogens (45%), followed by Candida tropicalis (29%) and lastely, Aspergillus fumigatus (26%). MIC50 and MIC90 of amphotericin B were 1g/ml and 4 g/ml, 1g/ml and 8g/ml and 1g/ml against Candida albicans, Candida tropicalis and Aspergillus fumigatus respectively. MIC50 and MIC90 of fluconazole were 8g/ml and 32g/ml, 1g/ml and 32g/ml and 8g/ml and 64g/ml against Candida albicans, Candida tropicalis and Aspergillus fumigatus respectively. MIC50 and MIC90 of itraconazoe were 1g/ml and 2g/ml, 1g/ml and 16g/ml and 2g/ml and 8g/ml against Candida albicans, Candida tropicalis and Aspergillus fumigatus respectively. MIC50 and MIC90 of ketoconazole were 1g/ml and 16g/ml, 0.5g/ml and 1g/ml and 4g/ml and 32g/ml against Candida albicans, Candida tropicalis and Aspergillus fumigatus respectively. Independent risk factors for acquiring fungemia in NICU were suction, prematurity and diabetes mellitus; in the (PHU) were neutropenia, intake of cytotoxics and antibiotics; in the (OU); neutropenia and cytotoxics. It is recommended that sound infection control policies and procedures be implemented to protect ICU patients from acquiring nosocomial fungemia. It is also recommended to restrict the use of antifungal drugs to indicated cases, so the potency of the available limited number of antifungal drugs can be reserved. ________________________________________ Primary Cutaneous
Actinomycosis and Treatment Yasoob Sulaiman, Hisham
Y. M. Ali1, and Manhil M. Yehia1
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