Spatial and temporal patterns of benthic macrofauna in Gorgan Bay, south Caspian Sea, Iran

We quantified the distribution, abundance and assemblage structure of macrofauna at 22 stations in Gorgan Bay, seasonally in 2012-2013. Also, depth, temperature, salinity, DO, TOM and sediment particle size were measured in each station. The highest concentration of TOM was measured near the western littoral zone (10.22) while the mouth part and north-eastern area was characterized by the lowest values (2.65 % and 4.69). A total of 31658 individuals belonging to 12 families and 14 species were identified. Polychaeta with 3 species was the most dominant group in terms of abundance. The four most abundant taxa making up 85% of all specimens were Streblospio gynobranchiata, Tubificidae, Hediste diversicolor and Abra segmentum. The maximum density (7,893 ind/m^2) was obtained at station 1 while the minimum (1,777 ind/m^2) was observed at station 16. The western area was characterized by the highest species diversity (H', 1.94) and the stations 10, 8 and 7 were characterized by the lowest diversity indices (H', 0.72, 0.77 and 0.87, respectively). The PCA showed that water parameters with more temporary variations had a greater significance in explaining the system variability, and a not marked but evident difference between the two parts of Gorgan Bay was observed and supported by nmMDS test. So Gorgan Bay presents transitional macrobenthic assemblages that are spatially distributed along substrate gradients but it seems that the coastal ecosystem of the south Caspian Sea and mouth-eastern part of Gorgan Bay is very dynamic and some species are forming a metapopulation toward western sites

Elimination of carbon monoxide using non-thermal plasma

Background and aims: Non-thermal plasma is considered as a successful new technology with high efficiency in the air pollution control. Various types of atmospheric pollutants adversely influence on the human health and the environment regionally and globally. Carbon monoxide has been introduced as a critical pollutant which can cause the environmental and health effects. The growing concerns about effects of air pollution on human health, and also more stringent strategies of choosing the air quality standards, have motivated the development of air pollution control techniques, particularly the non-thermal plasmas techniques. Therefore, the aim of this study is the removal of the carbon monoxide (CO) contaminants in the dry air and argon atmospheres in order to determine of the effective parameters. Methods: The current study has determined the effects of temperature, the CO concentration, the voltage and the residence time on the CO elimination efficiency by ASTM D 5835 method in the system of negative plasma reactor (diluted by dry air) and the system of positive plasma reactor (diluted by argon gas), simultaneously. Results: The results indicated that the temperature and the residence time did not have a significant effect on the CO removal in the both dry air and argon gas systems. However, the most important variable in the both systems was the voltage in the vicinity of 8 kilovolts with the p<0.05 and the mean effect of 37 and 13.2 in the dry air and argon gas systems, respectively. Conclusion: The results of CO elimination in the dry air and argon atmosphere indicate that the dry air system, due to present of the oxygen active ions, has better performance compared to the argon gas system

Assessment of Organophosphorus Pesticide Residues in Water and Sediment Collected from the Southern Caspian Sea

Pollution of water resources by uncontrolled pesticide use is a serious health and environmental issue. In this study, concentrations of three organophosphorus pesticides (diazinon, malathion, and azinphos-methyl) in water and sediment samples from five estuaries (Sefidrud, Chalus, Babolrud, Tajan, and Gorganrud) along the Caspian Sea were investigated. Samples were collected from surface water and sediment during summer to autumn, and pesticides were analysed by gas chromatography-mass spectrometry (GC-MS). Results indicated that salinity and turbidity in Gorganrud were higher (salinity: range 2–8%; turbidity: range 1–9%) compared to other stations. Higher diazinon (water: 0.08±0.06, sediment: 0.04±0.01), malathion (water: 0.09±0.06, sediment: 0.05±0.01) and azinphos-methyl (water: 0.1±0.08, sediment: 0.06± 0.02) concentrations were observed in the Tajan river compared to other stations. Mean concentrations of diazinon, malathion and azinphos-methyl pesticides were higher in the summer compared to the autumn. Azinphos-methyl concentrations were higher than sediment quality guidelines (SQGs), which warrants ongoing monitoring. Our research provides insights into the presence of organophosphate pesticides (OPs) in rivers that enter into the Caspian Sea. Further work to better understand the environmental pollution of OPs in the Caspian Sea is ongoing

Distribution pattern of heavy metals in the surficial sediment of Gorgan Bay (South Caspian Sea, Iran)

The Gorgan Bay is an important ecosystem receiving discharge from their tributaries. In this study, concentration of Pb, Zn, Ni, Fe, Al, Cu and As was seasonally determined at 22 sampling points during 2012-2013. Sediment samples were collected using a Van Veen grab. The levels of heavy metals were determined by ICP-AES (Inductively Coupled Plasma Atomic Emission Spectrometry) and AAS (Atomic Absorption Spectrophotometer). The percentages of sand, silt, clay and TOM (Total Organic Matter) in the sediment samples were determined (44.4± 15, 53.4 ± 14, and 2.2± 2.2 and 7.2% ± 1.6, respectively). The results showed that range of Al, As, Cu, Fe, Ni, Pb and Zn in the sediment samples were 0.4-2%, 2.6-8.6 ppm, 8.1-12.4 ppm, 0.9-1.2%, 11.5-16.8 ppm, 5.9-13.6 ppm and 21.8-28.8 ppm, respectively. In spring, both Al and Ni were higher than the guideline level. In the event that arsenic was exceeds the guidelines in summer. In general, according to the results of EF (Enrichment Factor) and PLI (Pollution Load Index) can be concluded, Gorgan Bay is low risk and not contaminated. According to the results of the nmMDS (non-metric Multidimensional Scaling), PCA (Principal Components Analysis) and the map of distribution of heavy metals, it seems Gorgan Bay are divided into two separate zones (the eastern and the western parts)

Molecular identification and phylogenetic classification of Leishmania spp. isolated from human cutaneous leishmaniasis in Iran: A cross-sectional study

Background: In Iran, both forms of cutaneous (CL) and visceral leishmaniasis (VL) have been reported; so the accurate species identification of the parasite(s) and the analysis of genetic diversity are necessary. Methods: The smears were collected from lesions samples of 654 patients with CL, who attended local health centers in 12 provinces of Iran during 2013-2015. The smears were checked for the presence of amastigotes by light microscopy. DNA of 648 Leishmania isolates, amplified by targeting a partial sequence of ITS (18S rRNA�ITS1�5.8S rRNA�ITS2) gene. Twenty-five of all the amplicons were sequenced and analyzed with restriction fragment length polymorphism (RFLP) using the Taq1 enzyme. Results: All the smears were positive microscopically. The PCR-RFLP analysis revealed that 176 (27) CL patients were infected with L. tropica and, 478 (73) with L. major. The dominant species in all over Iran is L. major. The sequencing results of all CL patients and RFLP analysis confirmed each other. Based on our phylogenetic tree, 25 ITS DNA sequences were grouped into two clusters representing L. major and L. tropica species. Phylogenetic tree derived from the ITS sequences supports a clear divergence between L. major from the other species. Conclusion: Discrimination of Iranian Leishmania isolates using ITS gene gives us this opportunity to detect, identify, and construct the phylogenetic relationship of Iranian isolates. © 2018, Tehran University of Medical Sciences (TUMS). All rights reserved

In vitro antibacterial activity and durability of a nano-curcumin-containing pulp capping agent combined with antimicrobial photodynamic therapy

Background: Considering the antibacterial properties of nano-curcumin (nCur) reinforced with antimicrobial photodynamic therapy (aPDT), this study aimed to assess the antibacterial activity and durability of Activa BioActive Base/Liner (ABBL) containing nCur (nCur-ABBL) as a pulp capping agent against Streptococcus mutans, the most common cause of secondary caries. Materials and methods: In this in vitro experimental study, ABBL discs containing 0.5 , 1, 2, and 5 (w/w) concentrations of nCur were fabricated. After aPDT using light emitting diode (LED) at 435 +/- 20 nm wavelength for 5 min, the discs were undergone aging in artificial saliva for 90 days. The antibacterial activity of the discs against S. mutans was evaluated by the disc agar diffusion test, and the number of bacterial colonies present in the biofilm formed on the disc surfaces was counted after 0, 15, 30, and 60 days of aging. Results: The maximum growth inhibition zone was noted around the 5 nCur-ABBL discs. Increasing the con-centration of nCur from 0.5 to 5 combined with aPDT significantly decreased the number of S. mutans colonies in the biofilm over time (P 0.05). Conclusion: According to our data, 5 nCur-ABBL revealed the largest growth inhibition zone in S. mutans culture. Moreover, 5 nCur can serve as an excellent ABBL additive in aPDT producer against S. mutans biofilms up to 60 days of aging period

Expression patterns of oxyR induced by oxidative stress from Porphyromonas gingivalis in response to photo-activated disinfection

Maryam Pourhajibagher,1&ndash;3 Roghayeh Ghorbanzadeh,4 Abbas Bahador1,3,5 1Department of Microbiology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran; 2Dental Implant Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; 3Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran; 4Private Practice, Tehran, Iran; 5Laser Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran Introduction: Porphyromonas gingivalis, an important endodontic pathogen, may be exposed to sublethal doses of photo-activated disinfection (sPAD) during root canal therapy. Such an exposure can affect bacterial survival and virulence features. In this study, we evaluated the effect of sPAD-related oxidative stresses on the expression of oxidative stress response gene (oxyR) in P.&nbsp;gingivalis clinical isolates surviving in vitro photodynamic treatment. Materials and methods: To determine the sPAD, 16 clinical P. gingivalis isolates photosensitized with toluidine blue O (TBO), methylene blue (MB), and indocyanine green (ICG) were irradiated with specific wavelength and energy density of diode laser corresponding to the photosensitizers following bacterial viability measurements. The effects of sPAD on the expression ratio of oxyR of 16 clinical P. gingivalis isolates were then assessed using quantitative real-time PCR (qRT-PCR) assay. Results: Maximum values of sPAD against P. gingivalis were 6.25, 15.6, and 25 &micro;g/mL at fluencies of 171.87, 15.6, and 93.75 J/cm2, respectively, for TBO-, ICG-, and MB-sPAD (P&gt;0.05). ICG-, MB-, and TBO-sPAD could increase the oxyR gene expression of the clinical P. gingivalis isolates 12.3-, 5.6-, and 8.5-fold, respectively. ICG-sPAD increased the expression of oxyR gene in clinical isolates of P. gingivalis ~1.5- and 2-fold higher than TBO- and MB-sPAD, respectively. Conclusion: Our results showed that upregulation of oxyR during sPAD may lead to better survival and increased pathogenicity of P. gingivalis isolates. Therefore, selection of appropriate photo-activated disinfection dosage should be considered for the successful treatment of endodontic infection. Keywords: antimicrobial photodynamic therapy, indocyanine green, methylene blue, oxidative stress, Porphyromonas gingivalis, toluidine blue O, low-level laser therap