Journal of Sciences, Islamic Republic of Iran
Volume:29 Issue: 3, Summer 2018

Root canal disinfection is one of the main factors governing success of endodontic therapy. Antimicrobial photodynamic therapy (aPDT) is presented as a promising antimicrobial therapy that can eliminate microbiota present in infected root canal systems. In this study, a series of experiments investigated the effects of aPDT on cell viability and biofilm degradation ability of endopathogenic microbiota. Enterococcus faecalis and Pseudomonas aeruginosa strains as the versatile pathogenic microbiota in endodontic infections were used as the tested strains. Curcumin (CUR) and light-emitting diode (LED) were used as the photosensitizer and light source, respectively. The antimicrobial and anti-biofilm effects of CUR-aPDT were assessed by colony forming unit (CFU), and crystal violet assays. CUR-aPDT significantly decreased the CFU/mL count of E. faecalis and P. aeruginosa compared to the control group (P

In recent years, the spread of drug-resistant strains of Streptococcus pneumoniae, as the most common causes of bacterial respiratory infections, threatens public health. Therefore, the use of new antimicrobial medicines to inhibit this pathogen is an urgent demand. In this research project, the inhibitory effects of thirty recently synthesized compounds including thiazole, thiazolidine, imidazole, tetrahydropyrimidine, oxazolidine and thiazepine derivatives against this bacterium have been studied as well. The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC), zone diameters of bacterial growth inhibition were also measured by a disk diffusion method. All the obtained results were compared with antibacterial effects of gentamicin and penicillin antibiotics. Among all investigated compounds, only derivatives 3d, 5a, 5b, 7, 9c, 15, 17c and 17d showed inhibitory effects against S. pneumonia. As a result, the most and least effects respectively belonged to thiazole derivative 15 and thiazepine derivative 17c with zone diameters of bacterial growth inhibition= 20.2, 9.3 mm, MIC= 64, 2048 μg/mL and MBC= 128, 4096 μg/mL. Whereas thiazole derivative 15 exhibited a good inhibitory activity against the mentioned pathogen, it can be replaced as a good agent instead of antibiotics.

The expression of heat shock protein 27 (Hsp27) as a chaperone protein, is increased in response to various stress stimuli such as anticancer chemotherapy. This phenomenon can lead to survive of the cells and causes drug resistance. In this study, a series of methanesulfonamide derivatives as dual Hsp27 and tubulin inhibitors in the treatment of cancer were applied to quantitative structure–activity relationship (QSAR) analysis. A collection of chemometrics methods such as MLR, FA-MLR, PCR, and GA-PLS was applied to make relations between structural characteristics and anti-proliferative activity of them against SKBR-3 breast cancer cell line. The best multiple linear regression equation was obtained from GA-PLS. Concerning this model, new potent lead compounds were designed based on new structural patterns using in silico-screening study. To obtain their binding mode, binding site and types of their interactions to both tubulin and HSP27, molecular docking studies were also conducted on these compounds. The validity of docking protocol was also explored. The results obtained from this docking study indicate that the important amino acids inside the active site cavity that are in charge of essential interactions with HSP27 are Arg140, Thr139, Phe138, Cys137, Arg136, Phe104, His103, Val101, and Asp100. And this important amino acids in essential interactions with tubulin are Asn258, Val238, Cys241, Asn350, Leu255, Met259, Val315, Thr353, Arg221, Thr179 and Ser178.

In this research seismicity parameters, repeat times and occurrence probability of large earthquakes are estimated for 35 seismic lineaments in Persian plateau and the surrounding area. 628 earthquakes of historical time and present century with MW>5.5 were used for further data analysis. A probabilistic model is used for forecasting future large earthquake occurrences in each chosen lineament. Based on the processing, it reveals that high risk (P>66%) regions in Iran for MW≥7.0 earthquake occurrence in the next 20 years are Apsheron, Main Recent Fault, Dasht-e Bayaz, Golbaf, Minab, Makran and Bandar-e Abbas areas. North Tabriz fault and Ipac, Toroud and Neyshabour fault systems, which are form the southern border between the north and central Iran, have the largest repeat times (>40 years) for 5.5≤MW

This study was carried out in the Ravar plain, a typical arid zone in southeastern Iran, with the objectives of evaluating hydrochemical quality of the groundwater resources and identifying the processes that modify the groundwater composition. Groundwater samples were collected from representative wells spread over the study area. Major cations and anions along with physico-chemical parameters were measured as per the standard methods. The study approach includes conventional graphical plots and multivariate analysis of the hydrochemical data to define the hydrogeochemical evaluation of groundwater system based on the ionic constituents, water types and hydrochemical facies. The results indicated that the groundwater in the study area is alkaline (pH 7.1–7.8), hard (TH 350-4000 mg/l) and brackish (TDS 868–13000 mg/l). The Chadha’s diagram shows that the prevalent water type is Na–Cl–SO4, with alkali metals exceeding the alkaline earth metals. Gibbs and Durov diagrams as well as ionic ratio plots indicated that evaporation, water–rock interaction and ion exchange are the main processes that regulate the groundwater quality. It was also found that the majority of groundwater samples are undersaturated with respect to evaporitic minerals and oversaturated with respect to carbonate minerals. The application of principal component analysis resulted in two PCs. PC I with loading on Cl-, Na, SO4-2, EC, and Ca which is related to degree of groundwater mineralization while PC II with opposite loadings of HCO3- and pH. The findings of the study may be applicable to areas with similar characteristics elsewhere in arid regions.

The study area is located in Jabal-Barez Ranges, southeastern part of Kerman Copper Belt (KCB), where the porphyry copper mineralization such as Kerver occurs. This article deals with the enhancement of hydrothermal alteration minerals for exploration of porphyry Cu mineralization, and differentiates intense hydrothermal alteration zones from those with low intensity. Shortwave Infrared (SWIR) bands of ASTER data were used for mineral enhancement. The spectra of representative alteration mineral assemblages consisting of sericite illite, kaolinite montmorillonite and epidote chlorite were extracted from SWIR bands of ASTER. The spectra were applied for mineral discrimination using Mixture Tuned Matched Filtering (MTMF) technique. The image processing results were verified using field observation, spectral measurements, thin section and X-ray diffraction studies of the samples. Findings exhibit ASTER capability to discriminate different alteration zones. Findings also significantly show the role of MTMF algorithm as a useful technique for mineral exploration.

One of the most important reactions of the URCA that lead to the cooling of a neutron star, is neutron beta-decay ( ). In this research, the energy spectra and wave functions of massive fermions taking into account the Anomalous Magnetic Moment (AMM) in the presence of a strong changed magnetic field are calculated. For this purpose, the Dirac-Pauli equation for charged and neutral fermions is solved by Perturbation and Frobenius series method, respectively. The results of the Frobenius series method are in good agreement with the results of Nikiforov-Uvarov method (NU). In continuous, using the calculated wave functions, the general relation of neutron decay cross-section in the non-relativistic limit has been obtained. This relation has been derived by the four-fermion Lagrangian within the framework of the standard model of weak interactions. These calculations from the perspective of nuclear astrophysics can be important.