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The regulatory role of Toll-like receptors after ischemic stroke: neurosteroids as TLR modulators with the focus on TLR2/4
Get PDFIschemic stroke is the most common cerebrovascular disease and considered as a worldwide leading cause of death. After cerebral ischemia, different pathophysiological processes including neuroinflammation, invasion and aggregation of inflammatory cells and up-regulation of cytokines occur simultaneously. In this respect, Toll-like receptors (TLRs) are the first identified important mediators for the activation of the innate immune system and are widely expressed in glial cells and neurons following brain trauma. TLRs are also able to interact with endogenous and exogenous molecules released during ischemia and can increase tissue damage. Particularly, TLR2 and TLR4 activate different downstream inflammatory signaling pathways. In addition, TLR signaling can alternatively play a role for endogenous neuroprotection. In this review, the gene and protein structures, common genetic polymorphisms of TLR2 and TLR4, TLR-related molecular pathways and their putative role after ischemic stroke are delineated. Furthermore, the relationship between neurosteroids and TLRs as neuroprotective mechanism is highlighted in the context of brain ischemia. © 2018, Springer Nature Switzerland AG
Inhibitory effects of chronic administration of vitamin D 3 on pentylenetetrazole-induced seizures in mice
Get PDFVitamin D 3 as a neuroactive steroid hormone plays an important role in the nervous system. Recent clinical and experimental studies have shown an association between vitamin D-related disorders and epilepsy. Therefore, this study was designed to examine the effects of chronic administration of vitamin D 3 on pentylenetetrazole (PTZ)-induced seizure in mice. This interventional study was conducted on 120 mice in 12 groups. Two control groups acutely and chronically received a mixture of almond oil and paraffin; three groups were acutely given vitamin D 3 at doses of 2000, 4000 and 6000 IU/kg; three groups chronically received vitamin D 3 with similar doses for two weeks and two groups chronically and acutely received a sub-effective dose of vitamin D 3 and diazepam. Slow intravenous infusion of PTZ (5 mg/mL) was performed at a constant rate (0.3 mL/min) via an infusion pump to induce clonic and tonic seizures. Acute injection of different concentrations of vitamin D 3 (2000, 4000 and 6000 IU/kg i.p.) did not significantly increase a seizure threshold. However, a seizure threshold in the groups chronically treated with 4000, and 6000 IU/kg of vitamin D 3 was significantly higher than that in the control group (P < 0.001). Moreover, a combination of the sub-effective dose of vitamin D 3 (2000 IU/kg) and diazepam (0.1 mg/kg) significantly increased seizure threshold. Our findings suggest that administration of vitamin D supplement can be considered as a potential add-on treatment in seizure and due to the vitamin D deficiency results from the long-term use of most anti-seizure drugs, this supplementation becomes more important. © 201
Contribution of regulatory T cells to cancer: A review
No full textRegulatory T cells (Tregs) represent a low number of T-cell population under normal conditions, and they play key roles for maintaining immune system in homeostasis. The number of these cells is extensively increased in nearly all cancers, which is for dampening responses from immune system against cancer cells, metastasis, tumor recurrence, and treatment resistance. The interesting point is that apoptotic Tregs are stronger than their live counterparts for suppressing responses from immune system. Tregs within the tumor microenvironment have extensive positive cross-talks with other immunosuppressive cells including cancer-associated fibroblasts, cancer cells, macrophage type 2 cells, and myeloid-derived suppressor cells, and they have negative interactions with immunostimulatory cells including cytotoxic T lymphocytes (CTL) and natural killer cells. A wide variety of markers are expressed in Tregs, among them forkhead box P3 (FOXP3) is the most specific marker and the master regulator of these cells. Multiple signals are activated by Tregs including transforming growth factor-β, signal transducer and activator of transcription, and mTORC1. Treg reprogramming from an immunosuppressive to immunostimulatory proinflammatory phenotype is critical for increasing the efficacy of immunotherapy. This would be applicable through selective suppression of tumor-bearing receptors in Tregs, including FOXP3, programmed death-1, T-cell immunoglobulin mucin-3, and CTL-associated antigen-4, among others. Intratumoral Tregs can also be targeted by increasing the ratio for CTL/Treg. © 2018 Wiley Periodicals, Inc
Loop-mediated isothermal amplification assay for identification of clinical Enterococcus species
Get PDFBackground: Enterococci are recognized as a cause of nosocomial infections and a major public health problem. The reliable identification to the species level of enterococci should be considered. Objectives: The study aimed to develop a LAMP assay for the rapid and accurate detection of Enterococcus faecalis and E. faecium. Methods: In total, 57 enterococcal isolates from UTI patients were identified using conventional microbiological methods. Two sets of specific primers were designed for E. faecalis and E. faecium targeting the mtlf and efmC genes, respectively. The LAMP assays were conducted using specific primers, dNTPs, MgSO4, Bst DNA polymerase, and templates. Results: The results of phenotypic testing indicated that of the 57 enterococcal isolates, 49 (85.9) were identified as E. faecalis and eight (14.1) as E. faecium. The optimal reaction temperatures in the LAMP assays were 60 and 61°C for the detection of E. faecalis and E. faecium, respectively. All the 57 enterococcal isolates were identified as E. faecalis by the LAMP assay. Conclusions: The present study highlights the importance of the LAMP assay as a rapid and confirmatory tool for the identification of clinical Enterococcus spp. © 2019, Archives of Clinical Infectious Diseases
Evaluation of the thermal properties of SrCO3-microencapsulated palmitic acid composites as thermal energy storage materials
No full textA novel composite of SrCO3-microencapsulated palmitic acid (PA) (PA@SrCO3 microcapsules) was prepared an evaluated as a phase-change material through a self-assembly approach. Samples of the material were studied by Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometery (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) to determine the composition, crystalloid phase, microstructure, and morphology of the product. Also differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to monitor the thermal behavior of the PA@SrCO3 microcapsules. The data obtained through XRD and FTIR indicated the presence of characteristic peaks of PA and SrCO3, which is only possible when the species do not chemically react with each other. SEM images indicated the PA@SrCO3 microcapsules to be spheres with rough surfaces and average diameters of 1.5�2 µm. TEM images proved the samples as being composed of PA cores encapsulated in a SrCO3 coating. The DSC results showed that the samples had phase-change behaviors, similar to those of pristine PA (melting point = 66.9 °C, latent melting heat = 48.8 J g�1, freezing point = 55.7 °C, latent freezing heat = 43.2 J g�1, at a microencapsulation ratio of 43.92), and TGA results showed improvements in the thermal stability of PA@SrCO3 microcapsules as opposed to PA, due to the presence of the SrCO3 shell. © 2019, Akadémiai Kiadó, Budapest, Hungary
Exosome loaded alginate hydrogel promotes tissue regeneration in full-thickness skin wounds: An in vivo study
No full textWound healing is known as one of the most complicated biological processes for injured skin caused by surgical, trauma, burns, or diabetic diseases, which causes a nonfunctioning mass of fibrotic tissue. Recent reports have suggested that exosomes (EXOs) secreted by this type of stem cells may contribute to their paracrine effect. In this study, the EXOs were isolated from the supernatant of cultured adipose-derived stem cells (ADSCs) via ultracentrifugation and filtration. The EXO loaded in the alginate-based hydrogel was used as a bioactive scaffold to preserve the EXO in the wound site in the animal model. The physical and biochemical properties of EXO loaded Alg hydrogel were characterized and results proved that fabricated structure was biodegradable and biocompatible. This bioactive wound dressing technique has significantly improved wound closure, collagen synthesis, and vessel formation in the wound area. Results offer a new viewpoint and a cell-free therapeutic strategy, for wound healing through the application of the composite structure of EXO encapsulated in alginate hydrogel. © 2019 Wiley Periodicals, Inc
Assessing Iranians' parental competence: Development and psychometric properties of the Children's Sexual Behavior Questionnaire (CSBQ-IR), Iranian Version
No full textBackground: Parents are the first line mediators in sexuality development of children. However, the majority of parents tend to have close supervision on children sexual behaviors, particularly in the conservative cultures. This article describes the development and psychometric evaluation of an instrument to measure Iranian parents' competence in caring and nurturing their children sexually. Methods: The questionnaire was designed based on the principles in measurement, Waltz's theory. The Iranian version of Children's Sexual Behavior Questionnaire (CSBQ-IR) was developed and completed by 386 mothers and 101 fathers who participated in a community-based sexuality education program in Tehran, capital of Iran. Reliability was assessed by Kuder-Richardson reliability coefficient and Split half. CSBQ-IR was evaluated for its construct, inclusiveness and content validity by principle component analysis. Results: The Kuder-Richardson reliability coefficient and Split half reliability were found 0.425 and 0.457 that was on acceptable range. Meaning, grammar, wording and item allocation of the questionnaire were found to be appropriate with (content validity ratio CVR = 0.99) and (content validity index CVI = 0.8) respectively. Conclusion: CSBQ-IR provides a valid assessment of the parents' competency or incompetency in nurturing, communication, and managing their children's sexual behaviors. © 2019 Tabriz University of Medical Sciences. All rights reserved
Medicinal Plants As Natural Polarizers of Macrophages: Phytochemicals and Pharmacological Effects
No full textMacrophages are one of the crucial mediators of the immune response in different physiological and pathological conditions. These cells have critical functions in the inflammation mechanisms that are involved in the inhibition or progression of a wide range of diseases including cancer, autoimmune diseases, etc. It has been shown that macrophages are generally divided into two subtypes, M1 and M2, which are distinguished on the basis of their different gene expression patterns and phenotype. M1 macrophages are known as pro-inflammatory cells and are involved in inflammatory mechanisms, whereas M2 macrophages are known as anti-inflammatory cells that are involved in the inhibition of the inflammatory pathways. M2 macrophages help in tissue healing via producing anti-inflammatory cytokines. Increasing evidence indicated that the appearance of different macrophage subtypes is associated with the fate of diseases (progression versus suppression). Hence, polarization of macrophages can be introduced as an important venue in finding, designing and developing novel therapeutic approaches. Albeit, there are different pharmacological agents that are used for the treatment of various disorders, it has been shown that several natural compounds have the potential to regulate M1 to M2 macrophage polarization and vice versa. Herein, for the first time, we summarized new insights into the pharmacological effects of natural compounds on macrophage polarization. Copyright© Bentham Science Publishers; For any queries, please email at [email protected]
Protective effect of metformin, resveratrol and alpha-lipoic acid on radiation-induced pneumonitis and fibrosis: A histopathological study
No full textBackground: Radiation-induced pneumonitis and fibrosis are the most common side effects of chest radiotherapy. They result from massive and chronic production of Reactive Oxygen Species (ROS), inhibition of antioxidant enzymes as well as the release of several inflammatory mediators. In this study, we aimed to detect the radioprotective effects of metformin (as inhibitor of mitochondrial ROS), resveratrol (as stimulator of antioxidant defense enzymes) and alpha-lipoic acid (as direct antioxidant) for alleviating radiation-induced pneumonitis and fibrosis. Methods: 80 Male Mice were randomly allotted to eight groups which include G1: control; G2: res-veratrol; G3: alpha-lipoic acid; G4: metformin; G5: radiation; G6: radiation plus resveratrol; G7: radiation plus alpha-lipoic acid; G8: radiation plus metformin. Drugs� doses were as follows: 100 mg/kg metformin, 200 mg/kg resveratrol and 200 mg/kg alpha-lipoic acid. Irradiation with a single radiation dose of 18 Gy was performed using a cobalt-60 (60Co) gamma-ray source. After 80 days, all mice were sacrificed and their lung tissues evaluated for morphological changes using histopathological markers. Results: Irradiation led to acute pneumonitis including infiltration of inflammatory cells and dam-ages to alveolar and vascular, as well as mild fibrosis. Metformin, alpha-lipoic acid and resveratrol were able to reduce pneumonitis and overcome radiation-induced fibrosis. Conclusion: All agents could protect against radiation-induced lung injury moderately. It is possible that administering higher doses of these drugs over a long period of time could give better radiopro-tection of the lung. © 2019 Bentham Science Publishers
The effects of vitamin d supplementation on muscle function among postmenopausal women: A systematic review and meta-analysis of randomized controlled trials
Get PDFThe loss of muscle mass and its strength is one of the most critical changes in aging which is associated with an increased risk of falls, osteoporotic fractures and mobility disability. Vitamin D, with its extra-skeletal benefits, might improve muscle function in elderly. The current systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to summarize available relevant data and determine the effect of vitamin D supplementation on muscle function among postmenopausal women. We reached databases including; Cochrane library, Embase, PubMed, and Web of Science database until the end of May 2018 to identify relevant published RCTs. Heterogeneity among included studies was assessed using Q-test and I2 statistics. Random-effect model was applied to pool data and weighted mean difference (WMD) was calculated representing summary effect size. Outcomes of interest included the effects of vitamin D supplementation on hand grip strength (HGS), back muscle strength (BMS), and Timed Up and Go (TUG). Twelve RCTs out of 1739 potential reports were included in our meta-analysis. The pooled findings showed that vitamin D supplementation had no significant effect on HGS (WMD -0.03 kilogram (Kg); 95 CI, -0.26, 0.20; P=0.78), BMS (WMD 7.21 newton (N); 95 CI, -5.98, 20.40; P=0.28), and TUG (WMD 0.01 second (S); 95 CI, -0.17, 0.18; P=0.93) in postmenopausal women. Overall, the current meta-analysis showed that taking vitamin D supplementation by postmenopausal women did not affect markers of muscle function. Further studies are required to confirm the effect of vitamin D supplementation on markers of muscle function. © 2019, Leibniz Research Centre for Working Environment and Human Factors. All rights reserved