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Behrouz Taheri,1,2 Mohsen Mohammadi,3 Niloofar Momenzadeh,3 Zahra Farshadzadeh,2,4 Mona Roozbehani,5 Parva Dehghani,3 Sobhan Hajian,6 Sadegh Darvishi,6 Jebreil Shamseddin71Department of Medical Laboratory Sciences, School of Paramedicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 2Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 3The Persian Gulf Marine Biotechnology Research Center, The Persian Gulf Biomedical Sciences Research Institute, Bushehr University of Medical Sciences, Bushehr, Iran; 4Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 5Department of Medical Parasitology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; 6Student Research Committee, Bushehr University of Medical Sciences, Bushehr, Iran; 7Infection and Tropical Diseases Research Center, Hormozgan Health Institute, Hormozgan University of Medical Sciences, Bandar Abbas, IranPurpose: Piscidin-1 is an effective antimicrobial peptide (AMP) against a variety of microbes. However, its toxicity has been reported as a limitation for its potential therapeutic applications. The toxicity of piscidin-1 may be related to the long nonpolar face of this AMP. Here, we investigated different piscidin-1 analogs to reach a peptide with the reduced toxicity.Material and methods: In vitro and in vivo antibacterial activity and toxicity of piscidin-1 analogs generated by replacement of isoleucine at the border (I9) or the center (I16) of the nonpolar face of piscidin-1 by alanine or lysine were investigated.Results: The results indicated that among all peptides, piscidin-1 with the highest HPLC retention time (RT) and I16K-piscidin-1 with the lowest RT had the highest and lowest cytotoxicity, respectively. Although I16K-piscidin-1 possessed the same MIC value as the parent peptide (piscidin-1) and other analogs, I16K-piscidin-1 exhibited a higher rapidity of bactericidal action at 5×MIC. The β-galactosidase leakage and propidium iodide staining assays indicated a higher pore-forming capacity of I16K-piscidin-1 relative to the parent peptide (piscidin-1). Taken together, RT is suggested to have a direct association with the toxicity and an inverse association with the rapidity of bactericidal action and pore-forming capacity. After infection of mice with clinical colistin-resistant Acinetobacter baumannii or clinical methicillin-resistant Staphylococcus aureus strains, treatment with I16K-piscidin-1, but not piscidin-1 and other analogs, resulted in a significantly stronger bactericidal potency. Furthermore, I16K-piscidin-1 exhibited the lowest in vivo toxicity.&#x00A0Conclusion: Overall, in vitro and in vivo comparison of piscidin-1 and its analogs together documented that replacement of isoleucine at the center of the nonpolar face of piscidin-1(I16) by lysine leads to not only a decrease in toxicity potential but also an increase in bactericidal potential.Keywords: antimicrobial peptide, piscidin-1, toxicity activity, Staphylococcus aureus, Acinetobacter baumannii

Background and Objective: The incidence of ectopic pregnancy is increasing due to artificial reproductive technology and increasing rate of sexual transmitted diseases. Ectopic pregnancy is the most common cause of maternal mortality in the first trimester and it reduces the chance of future successful pregnancy. Identifying the risk factors can help to reduce the maternal mortality and morbidity due to early diagnosis and on time treatment. This study was carried out to assess the risk factors in ectopic pregnancy in northern, Iran. Materials and Methods: This case control study was carreid out on 150 patients with ectopic pregnancy as cases and 300 women with normal pregnancy as controls. The subjects were selected from teaching hospital in Babol in northern Iran, during 2005-09. The risk factors include history of tuble surgery, ectopic pregnancy, cesarean section, pregnancy with IUD, infertility, assisted fertility with IUI, multiple partener, pre-eighteen years marriages were recorded for each subject by direct interview and file. Data were analyzed using SPSS-16 and Chi-Square and exat Fisher tests. Results: Theraputic assisted fertility with IUI (95% CI: 3.02-185.09, OR: 23.6, P

Background&Objective: Due to side-effects of diabetes mellitus in pregnancy, the rapid diagnosis and its treatment is very important. The aim of this study is to determine gestational diabetes mellitus (GDM) incidence in pregnant women. Materials&Methods: This survey is an analytic cross sectional study that evaluated 401 pregnant women in Babol Obstetrics Clinic. A Glucose Challenge Test (GCT) was done for all of the high risk women for diabetes in the first trimester and for other pregnant women in 24-28 gestational weeks. If GCT was positive (Blood sugar>135 mg/dl one hour after oral administration of 50gr Glucose), then a Glucose Tolerance Test (GTT) was done. For women with a positive GTT, the diagnosis was GDM. Results: In 401 pregnant women with a mean age of 24.69±5.31 four patients had overt diabetes (1%). In another 397 women, a GCT was done and 44 women (11% of all patients) had a positive GCT and 19 patients (4.7% of all patients) had GDM of those with GDM 26.3% need insulin therapy in addition to a diabetic diet. We noted there was also a positive relation between age and impaired GCT (P

The effects of geometrical and material parameters of fluence transmission experiments were studied for glasses with a variety of compositions using a tight focus geometry.The greatest thermal lensing properties were found in lead silicate glasses and it was assumed that glass materials should have high values of absorption coefficient, small valuesfor specific heat capacity and a random network structure with a maximum numberof degrees of freedom to maximize thermal lensing.

We have studied the specific heat and the thermal conductivity in a 4-(n-octyl)-4'-cyanobiphenyl liquid crystal (LC)-photochromic molecules mixture, before, during, and after the photo-activation of the dispersed photochromic molecules, over both the smectic A-nematic and the nematic-isotropic phase transitions. The evaluation of the specific heat has enabled the determination of the changes of the phase transition characteristics induced by the photochromic molecules photoisomerization, while that of the thermal conductivity could be used to monitor the modifications induced in the average LC molecular orientation. The polarization microscopy imaging of the sample texture constituted a valuable support for the interpretation of the obtained thermal conductivity results. [ABSTRACT FROM AUTHOR]

The properties of permanent, laser induced refractive index gratings in rare-earth doped glasses have been characterized in a variety of materials including lithium borates, lead and magnesium silicates, lead borate-germanates and lead germanates. This work is combined with the previous results obtained on phosphate and silicate glasses to develop an understanding of the effects of glass composition (both network former and modifier ions) on the ability of a material to produce gratings with high scattering efficiencies. The grating efficiencies and the writing/erasing dynamics were studied, and the two-level-system-model developed previously was employed to explain the results. The results show the importance of having flexible glass networks with low polarizing power of the network former ions, and a high content of nonbridging oxygen ions. In addition, it is important to have light, highly polarizable modifier ions with weak chemical bond strengths to the oxygen ions. This type of glass combined with rare-earth ions that like to exist in more than one local coordination environment and that couple strongly to high energy vibrational modes of the host, are found to be very effective in producing local structural changes that lead to room-temperature-stable refractive index gratings. [ABSTRACT FROM AUTHOR]