Source, occurrence, and fate of pharmaceuticals in natural waters

The consumption of pharmaceuticals has increased in the last few decades. After usage, pharmaceuticals are excreted via urine and feces and transported to wastewater treatment plants (WWTPs) where they are subjected to treatment processes, and finally discharged into rivers. In order to assess aquatic risk associated with short- and long-term exposure to pharmaceuticals, temporal-spatial variability in the concentrations should be monitored in different water compartments. In this thesis, occurrence and fate of pharmaceuticals and other organic pollutants were studied in Swedish and Canadian rivers and WWTPs, and the major sources of contaminations were identified. The ranges of mean concentrations of the pharmaceuticals and personal care products (PPCPs), hormones, and pesticides were 2.4-13755 ng L-1 and 0.5-112 ng L-1 in treated wastewaters and rivers, respectively. WWTPs and combined sewer overflows (CSOs) were identified as major sources of PPCPs in rivers. However, a large gathering of people at a river shore could temporarily contribute to a high input of pharmaceuticals. A temporal study of mass flows and corresponding removal efficiencies (REs) of WWTP-derived pharmaceuticals showed winter accumulations for most of the compounds. This might reflect high water flow rates and negligible rates of bio- and phototransformation in this season. REs of beta-blockers were season-dependent, with the highest removal in the summer and fall. This was due to biotransformation, indicated by high water temperature and chlorophyll a mass flows during those seasons. Yearly median REs of nutrients were low compared to pharmaceuticals. Yet, REs of atenolol and nitrate-nitrogen (NO3-N) were related and had similar seasonal trends. Carbamazepine REs were the lowest among the pharmaceuticals. The latter combined with the persistence of carbamazepine in WWTPs and a lake showed its potential as an indicator of cumulative contamination. A correlation between caffeine concentrations and fecal coliforms in rivers confirmed caffeine as an indicator of recent urban fecal contamination. A high caffeine/carbamazepine ratio might be indicative of raw sewage discharge in a river, justified by higher concentrations of caffeine than carbamazepine in raw sewage and negligible removal of carbamazepine in WWTPs. The outcomes of the thesis show that source characteristics, water flow rates, and environmental conditions are essential factors that control detection frequency, concentrations and associated mass flows, and the fate of pharmaceuticals in aquatic environments. Also, pharmaceuticals can be used as indicators of recent and cumulative fecal contamination in drinking water sources

Wnt Signaling in Stem Cells and Cancer

__Abstract__ Mammalian development starts from a fertilized egg that initially generates few pluripotent cells which eventually give rise to the embryo proper. Different ‘flavors’ of pluripotency have been captured in vitro which led to the establishment of different pluripotent cell lines. Mouse embryonic stem cells (mESCs) are derived from the preimplantation embryo and have three defining properties: self-renewal, pluripotency, and contribution to chimera formation. By applying specific culture conditions or ectopic expression of the pluripotency factors, similar pluripotent cells can be derived from germ cells or differentiated cells referred to as embryonic germ (EG) and induced pluripotent cells (iPSCs), respectively. When established from post-implantation embryo, the cultured cells are termed epi stem cells (EpiSCs). EpiSCs have limited potential for chimerism and germ line transmission and require different culture conditions when compared to ESCs. Hence, mouse ESCs and EpiSCs represent two different phases of pluripotency usually referred to as the naïve and primed states. By employing genetic manipulation or specific culture conditions, the different pluripotent cells can be interconverted which leads to several intermediate states. Unlike their murine counterparts, human ESCs closely resemble the rodent primed EpiSCs and respond to similar signaling pathways. Tumorigenic transformation of primordial germ cells (PGC) and gonocytes can also give rise to pluripotent cells known as embryonal carcinoma cells (hECs), thought to represent the malignant counterpart of hESCs. Among different signaling pathways, Wnt signaling plays a central role in self-renewal and differentiation of pluripotent cells

Evaluation of Porin Interaction with Adenine Nucleotide Translocase and Cyclophilin-D Proteins after Brain Ischemia and Reperfusion

Objective (s) Porin is a mitochondrial outer membrane channel, which usually functions as the pathway for the movement of various substances in and out of the mitochondria and is considered to be a component of the permeability transition (PT) pore complex that plays a role in the PT. We addressed the hypothesis that porin interacts with other mitochondrial proteins after ischemic injury.Materials and MethodsFor this purpose, we used in vivo 4-vessel occlusion model of rat brain and porin purification method by hydroxyapatite column. After SDS gel electrophoresis and silver nitrate staining, Western blotting was done for porin, adenine nucleotide translocase and cyclophilin-D proteins.Results Porin was purified from mitochondrial mixture in ischemic brain and control groups. Investigation of interaction of adenine nucleotide transposes (ANT) and cyclophilin-D with porin by Western blotting showed no proteins co-purified with porin from injured tissues.Conclusion The present study implies that there may not be interaction between porin, and ANT or cyclophilin-D, and if there is any, it is not maintained during the purification procedure

Decreased expression of heat shock protein HSP90α after exposure to doxorubicin in breast cancer cell lines (MCF-7 and MDA-MB-231)

Background and purpose: Incidence of breast cancer is increasing day by day. Scientists are interested in the effects of inhibition of breast cancer cell on treatment of this cancer. The aim of this study was to determine IC50 of doxorubicin in 24 hours on cell lines MCF-7 and MDA-MB-231 and the expression of heat shock protein HSP90α as a factor in the cell before and after 24 hours exposure to doxorubicin in both breast cancer cell lines. Materials and methods: A descriptive interventional study was done in two cell lines MCF-7 and MDA-MB-231` after 24 hours exposure to doxorubicin. Sensitivity of cells to doxorubicin was determined using MTT Assay in excel software. HSP90α heat shock protein expression were qualitatively compared in both cell lines before and after exposure to doxorubicin using immunofluorescent techniques (Immunocytochemistry). Results: MTT Assay showed that IC50 value in MDA-MB-231 and MCF7 cells after 24 hours exposure to doxorubicin (the dose that kills 50% of cells) were 14.521 and 16.3315µM, respectively. Immunocytochemistry revealed that HSP90α protein expression in both cell lines after exposure to doxorubicin decreased compared to the control group. Conclusion: Cell density in cell lines (ER-) MDA-MB-231 and line MCF-7 (ER+) after exposure to doxorubicin and increasing the dose of medication, decreased indicating a dose dependent effect. Also, apoptosis occurred in both cell lines and expression of HSP90α decreased but MDA-MB-231 cells were found to be more sensitive. © 2017, Mazandaran University of Medical Sciences. All rights reserved

Mesenchymal stem cells improve ischemic stroke injury by anti-inflammatory properties in rat model of middle cerebral artery occlusion

Background: Ischemic stroke is a major cause of permanent disability and inflammation has a prominent role in stroke pathology. Stem cell therapy is a new approach for stroke treatment. Mesenchymal stem cells (MSCs) are appropriate for this approach due to neuroprotective and immunomodulatory effects. Objectives: In this experimental study, the neuroprotective effects of mesenchymal stem cells (MSCs) on brain injury after transient middle cerebral artery occlusion (tMCAO) in rats was investigated with emphasis on inflammatory factors. Methods: Mesenchymal Stem Cells were isolated from bone marrow of rats and expanded by cell culture. Thirty-six male Wistar rats were randomly selected and divided to 6 groups. The MCAO model was performed in 4 groups with 24 and 72 hours of reperfusion. A single infusion of 2 × 106 MSCs was transplanted in one of the 24-hour and 72-hour groups and others received saline. In the sham groups, surgery was done without MCAO. Behavioral tests were evaluated and infarct volume was measured by staining of brain sections. Serum levels of Interleukin (IL) 1β and Tumor necrosis factor (TNF) α were measured by the enzyme linked immunosorbent assay (ELISA). Relative expression of Interleukin (IL)1β, tumor necrotizing factor (TNF)α, and IL6 genes were assessed in penumbra of the ischemic region using real time polymerase chain reaction (PCR). Results: The study results indicated that total behavioral scores were increased 72 hours after MSC transplantation (14.5 ± 2.0, P < 0.01). Moreover, MSCs decreased the infarct volume both 24 hours (18.82 ± 1.58, P < 0.01) and 72 hours (14.4 ± 1.53, P < 0.05) after MCAO. Serum levels of IL-1β and TNFα were increased after MCAO, yet MSCs transplantation decreased IL-1β (368.3 ± 109.5, P < 0.001) and TNFα (126.9 ± 38.6, P < 0.01) compared to saline. Also, relative gene expression of IL1β, TNFα, and IL6 was decreased by MSCs transplantation (P < 0.05). Conclusions: The MSCs had a neuroprotective effect in ischemic stroke via modulation of inflammatory response, and serum levels of IL1β and TNFα could be used as markers for evaluating anti-inflammatory effects of MSCs

Morphology of Rat Hippocampal CA1 Neurons Following Modified Two and Four-Vessels Global Ischemia Models

Background: An appropriate animal model of ischemia stroke is essential for evaluation of different therapeutic methods. Two and four-vessel global ischemia models are one of the most common types of transient cerebral ischemia. Objectives: In this study, the morphology of rat hippocampal CA1 neurons in modified models of two and four-vessel ischemia and reperfusion were evaluated. Materials and Methods: In this study, 20 Wistar rats were randomly divided into five groups. In group 2 and 3, both common carotid arteries were occluded for 10 minutes in either 3 or 24 hours of reperfusions, respectively. In group 4 and 5, both common carotid and vertebral arteries were occluded for 10 minutes in either 3 or 24 hours of reperfusions, respectively. Group 1 as control, underwent the whole surgery without any arteries occlusion. Hippocampi of the rats in all groups were processed and tissue sections were stained using the Nissl method. The morphology of CA1 neurons were studied under a light microscope and compared different groups. Results: In all groups ischemic changes were apparently observed in hippocampus CA1 neurons. In two-vessel occlusion model, after 3 and 24 hours of reperfusions, ischemic cells accounted for 14.9% and 23.2%, respectively. In four-vessel occlusion model, after 3 and 24 hours of reperfusions, ischemic cells accounted for 7.6% and 44.9% (P < 0.0001), respectively. Conclusions: Modified four-vessel occlusion model resulted in significant ischemic changes after 24 hours of reperfusion in CA1 neurons of rat hippocampus

Comparison of the effects of progesterone and 17 β-estradiol on Schwann cell markers expression in rat adipose-derived stem cells

Steroids promote the myelination and regeneration in the peripheral nervous system. Whereas, little is known about the inducing effects by which the hormones exert their effects on Schwann cells differentiation. This could be revealed by the expression of Schwann cell markers in adipose-derived stem cells (ADSCs). The purpose of this study was to present the effects of progesterone and 17 β-estradiol on the Schwann cell markers in rat ADSCs. The mesenchymal stem cell markers (CD73, and CD90) were assayed by flow cytometry. Rat ADSCs were sequentially treated with β-mercaptoethanol, and all-trans-retinoic acid, followed by a mixture of basic fibrobroblast growth factor, platelet-derived growth factor, forskolin and heregulin. In experimental groups, forskolin and heregulin were substituted by progesterone and 17 β-estradiol. After induction, the expression of Schwann cell markers P0, and S-100 and the cellular immunocytochemical staining positive rate of anti-S100 and anti-glial fibrillary acidic protein (GFAP) antibodies were compared in the experimental and control groups. Progesterone and 17 β-estradiol triggered P0 and S-100 genes expression and induced a cellular immunocytochemical staining positive rate of S-100 and GFAP in rats ADSCs. Progesterone induced these changes stronger than 17 β-estradiol. Thus, progesterone may induce rat ADSCs toward Schwann-like cells by expression of Schwann cell markers and is more potent than 17 β-estradiol in the expression of these markers. © 2018 Urmia University. All rights reserved

Vitamin B12 supplementation in end stage renal diseases : A systematic review

Acknowledgements The authors wish to thank Hossein Ansari, Javad Tarrahi, Dr. Sakineh Shabbidar and Dr. Hadi Tabibi for their technical and valuable comments.Peer reviewedPublisher PD

The Role of Mitochondrial DNA (mtDNA) in the Development of Diabetic Retinopathy (DR): A Systematic Review

Diabetic Retinopathy (DR) is the most prevalent health problem, which is influenced by environmental and genetic factors with an increasing prevalence. The current systematic review is focused on mtDNA modification, including polymorphism and mutation/deletion, with a direct effect on DR. This systematic search was initially done through PubMed, Cochrane, EMBASE, SCOPUS, and Web of Science without a restriction on the years of publication. The terms searched included ‘‘mtDNA’’, ‘‘mitochondrial DNA’’, ‘‘diabetes’’, ‘‘diabetic’’, ‘‘retina’’, and ‘‘diabetic retinopathy’’. Animal, cohort, cross-sectional, and in vitro studies, as well as case series, case reports, review articles, and Letters to Editor were excluded from this research. From 1528 resulting searched articles, only 12 papers were finally chosen as the case-control studies considering  mtDNA gene and DR. Actually, of these 12 articles, 8 studies were concerned with mtDNA polymorphisms (UCP1, UCP2, ROMO-1, and Mn-SOD) and 4 articles were related to mtDNA mutation (A3243G mutation in tRNALeu(UUR) gene and mtDNA deletion (ΔmtDNA 4977)). Some conflicting results were found between the selected genetic modifications of mtDNA, such as Mn-SOD, UCP1, ΔmtDNA 4977, tRNALeu (UUR), and ROMO-1. Finally, A3243G mutation in the tRNALeu (UUR) gene and rs660339 and V16A polymorphisms of UCP2 and Mn-SOD genes were respectively considered as the most important factors in the pathogenesis of DR.Â