Assembly, growth and conductive properties of tellurium nanorods produced by Rhodococcus aetherivorans BCP1

Tellurite (TeO32-) is a hazardous and toxic oxyanion for living organisms. However, several microorganisms can bioconvert TeO32- into the less toxic form of elemental tellurium (Te0). Here, Rhodococcus aetherivorans BCP1 resting (non-growing) cells showed the proficiency to produce tellurium-based nanoparticles (NPs) and nanorods (NRs) through the bioconversion of TeO32-, depending on the oxyanion initial concentration and time of cellular incubation. Te-nanostructures initially appeared in the cytoplasm of BCP1 cells as spherical NPs, which, as the exposure time increased, were converted into NRs. This observation suggested the existence of an intracellular mechanism of TeNRs assembly and growth that resembled the chemical surfactant-assisted process for NRs synthesis. The TeNRs produced by the BCP1 strain showed an average length (>700 nm) almost doubled compared to those observed in other studies. Further, the biogenic TeNRs displayed a regular single-crystalline structure typically obtained for those chemically synthesized. The chemical-physical characterization of the biogenic TeNRs reflected their thermodynamic stability that is likely derived from amphiphilic biomolecules present in the organic layer surrounding the NRs. Finally, the biogenic TeNRs extract showed good electrical conductivity. Thus, these findings support the suitability of this strain as eco-friendly biocatalyst to produce high quality tellurium-based nanomaterials exploitable for technological purposes

An open source, parallel DSMC code for rarefied gas flows in arbitrary geometries

This paper presents the results of validation of an open source Direct Simulation Monte Carlo (DSMC) code for general application to rarefied gas flows. The new DSMC code, called dsmcFoam, has been written within the framework of the open source C++ CFD toolbox OpenFOAM. The main features of dsmcFoam code include the capability to perform both steady and transient solutions, to model arbitrary 2D/3D geometries, and unlimited parallel processing. Test cases have been selected to cover a wide range of benchmark examples from 1D to 3D. These include relaxation to equilibrium, 2D flow over a flat plate and a cylinder, and 3D supersonic flows over complex geometries. In all cases, dsmcFoam shows very good agreement with data provided by both analytical solutions and other contemporary DSMC codes

Effect of Surgical Flap on IL-1β and TGF-β Concentrations in the Gingival Crevicular Fluid of Patients with Moderate to Severe Chronic Periodontitis

Background: Growth factors play a major part in wound healing in many tissues including the periodontium. Transforming growth factor-β1 (TGF-β1) is one of these factors present in the gingival crevicular fluid. In addition, it is considered as one of the most important anti-inflammatory cytokines. Interleukin-1β is a proinflammatory cytokine that presents itself in gingival inflammation and the GCF. Such factors might be of value as prognostic markers of wound healing activity and the therapeutic progress following flap surgery. Objective: The aim of this study was to evaluate the effect of surgical flap on the concentration of IL-1β and TGF-β in the GCF of patients with moderate to severe chronic periodontitis. Methods: The GCF samples were collected, using the Perio-Paper strip at phase 1 (pre-surgery), phase 2 (4th week post surgery) and phase 3 (12th week post surgery) from 20 sites of 10 patients undergoing flap surgery. After the elution, IL-1β and TGF-β concentrations were measured by enzyme-linked immunosorbent assay (ELISA). Results: The mean TGF-β and IL-1β concentration decreased from phase 1 to phase 3 (p<0.05). There were no significant statistical correlations between IL-1β and TGF-β1 concentrations in the 3 assessment phases. There was a significant statistical correlation between TGF-β1 concentrations and the Plaque Index (PI) in phase 2 (p<0.05). There was a significant statistical correlation (p<0.05) between IL-1β and TGF-β1 concentration and the probing pocket depth (PPD). Conclusion: The flap surgery has a significant effect on decreasing IL-1β concentration. In the case of TGF-β1, probably the decrease in the concentration after treatment might be due to the removal of the inflammatory stimulants

One-dimensional Modelling and Optimisation of an Industrial Steam Methane Reformer

Steam methane reforming is one of the most promising processes to convert natural gas into valuable products such as hydrogen. In this study, a one-dimensional model was used to model and optimise an industrial steam methane reformer, using mass and thermal balances coupled with pressure drop in the reformer tube. The proposed model was validated by the experimental data. Furthermore, the effects of flowrate and temperature of the feed, tube wall temperature, and tube dimension on the reformer performance were studied. Finally, a multiobjective optimisation was done for methane slip minimisation and hydrogen production maximisation using genetic algorithm. The results illustrated the optimum feed flowrate of 2761.9 kmol h–1 (minimum 32 mol.% produced hydrogen and maximum 0.15 mol.% unreacted methane). This is one of the few studies on investigation of steam methane reformer using a simple and effective model, and genetic algorithm. This work is licensed under a Creative Commons Attribution 4.0 International License

The effects of probiotics, prebiotics and synbiotics on the reduction of IBD complications, a periodic review during 2009–2020

Aims: To perform a systematic review on randomized controlled trials to examine the efficacy of probiotics, prebiotics and synbiotics in the treatment of IBD. Methods and Results: PubMed, Web of science, Scopus and Google Scholar were systematically searched from January 2009 to January 2020 using the following keywords: ‘Inflammatory Bowel Disease’, ‘Probiotics’ and ‘Clinical trial’. The statistical analysis was performed using SPSS software version 24.0. A total of 1832 articles were found during the initial search and 21 clinical trials were eligible. Studies comparing the effects of probiotics and placebo among patients with active ulcerative colitis (UC) showed a significant difference in clinical outcomes. Moreover, probiotics improved the overall induction of remission rates among patients with Crohn’s disease (CD). Probiotics significantly decreased the IL-1β, TNF-α and IL-8 levels. Also, the need for systemic steroids, hospitalization, surgery, as well as histological score and disease activity index significantly decreased in patients who used probiotic or pro-/synbiotics. Conclusions: The use of probiotics, as food supplements, can induce anti-inflammatory reactions, balance the intestinal homeostasis and induce remission in IBD. The efficacy of probiotics on remission induction is more reported in UC rather than CD. Larger well-designed clinical trials are needed to further determine whether probiotics are of clear benefits for remission in IBD. © 2020 The Society for Applied Microbiolog

Cold gas analysis of a waste-gas incinerator to enhance mixing capabilities using CFD

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.Reducing the combustion length, improving the flame stability, generating sufficient vortical recirculation zones, and extending the durability of furnace insulation are some reasons to target swirling flow in combustion chambers with sufficient swirl characteristics. These reasons aim to increase the species residence time and improve the mixing quality in the related combustion chambers. As is known, burning the waste-gas material in incinerators can produce toxic pollutants. Nevertheless, one main objective in incineration combustor is to improve the flow mixing characteristics. Our concern in this paper is to improve the mixing characteristics of one available incinerator with some unsuitable pollution using the CFD simulation. We study the flow patterns and analyze the mixing quality to monitor the influence of waste-gas inlet crosssections and its position into the incinerator chamber. The degree of mixing is analyzed using the standard deviation parameter, which determines the homogeneity of the fuel mixture fraction in the incinerator chamber. The improvement of mixing characteristics and increasing the residence time in the incinerator are two important factors, which are suitably elaborated and discussed in this paper. The mixing study is provided for cold gas assumption.dc201

Preclinical studies of166Ho-chitosan for treatment of hepatocellular carcinoma

Introduction: Recently, due to the special characteristics of166Ho and chitosan,166Ho-chitosan complex was developed for treatment of tumors such as hepatocellular carcinoma. This complex has been lately prepared with high radiochemical purity in our lab. The preclinical studies of the complex however should be performed to evaluate the tracer concentration in target and normal tissues before human use. Methods: In this study,166Ho-chitosan was prepared and its preclinical studies for treatment of hepatocellular carcinoma was carried out by injection of the radiopharmaceutical into the rabbit's liver via two different methods, surgery and venography. Leakage of the injected activity from the injection site in the rabbit organs was investigated using SPECT and SPECT-CT imaging up to 24 hours. Results: Both SPECT and SPECT-CT imaging of the rabbits showed that there was no significant leakage of the injected activity. Almost all the activity would remain in the injection site at least 24 h post injection. Conclusion: Considering all of the excellent features of the complex, this radiopharmaceutical is suggestive for treatment of hepatocellular carcinoma by radioembolization method

Improvement of heart failure by human amniotic mesenchymal stromal cell transplantation in rats

Background: Recently, stem cells have been considered for the treatment of heart diseases, but no marked improvement has been recorded. This is the first study to examine the functional and histological effects of the transplantation of human amniotic mesenchymal stromal cells (hAMSCs) in rats with heart failure (HF). Methods: This study was conducted in the years 2014 and 2015. 35 male Wistar rats were randomly assigned into 5 equal experimental groups (7 rats each) as 1-Control 2-Heart Failure (HF) 3-Sham 4-Culture media 5-Stem Cell Transplantation (SCT). Heart failure was induced using 170 mg/kg/d of isoproterenol subcutaneously injection in 4 consecutive days. The failure confirmed by the rat cardiac echocardiography on day 28. In SCT group, 3�106 cells in 150 μl of culture media were transplanted to the myocardium. At the end, echocardiographic and hemodynamic parameters together with histological evaluation were done. Results: Echocardiography results showed that cardiac ejection fraction in HF group increased from 58/73 � 9 to 81/25 � 6/05 in SCT group (p value &lt; 0.001). Fraction shortening in HF group was increased from 27/53 � 8/58 into 45/55 � 6/91 in SCT group (p value &lt; 0.001). Furthermore, hAMSCs therapy significantly improved mean diastolic blood pressure, mean arterial pressure, left ventricular systolic pressure, rate pressure product, and left ventricular end-diastolic pressure compared to those in the HF group, with the values reaching the normal levels in the control group. A marked reduction in fibrosis tissue was also found in the SCT group (p value &lt; 0.001) compared with the animals in the HF group. Conclusion: The transplantation of hAMSCs in rats with heart failure not only decreased the level of fibrosis but also conferred significant improvement in heart performance in terms of echocardiographic and hemodynamic parameters. � 2016, Tehran Heart Center. All rights reserved

Nanoencapsulation of luminescent 3-hydroxypicolinate lanthanide complexes

We have synthesized luminescent nanoparticles comprising a core of lanthanide complexes and shells of amorphous silica using reverse micelles as nanoreactors. 3-Hydroxypicolinate complexes of Eu(III), Tb(III), and the corresponding heteronuclear complexes have been investigated as the photoactive cores. The size of the silica particles is within the nanometer scale, which, together with the ability for surface biofunctionalization, opens up perspectives for their use in bioapplications. Optical studies of the as-prepared nanoparticles reveal that the luminescence properties of the 3-hydroxypicolinate complexes in the matrices are markedly different from their original features

The effect of probiotics on respiratory tract infection with special emphasis on COVID-19: Systemic review 2010�20

To evaluate the effects of probiotics on respiratory tract infection (RTI) a systematic review of randomized controlled trials (RCTs) from January 2010 to January 2020 was conducted. The PubMed, Google Scholar, Embase, Scopus, Clinicaltrials.gov, and International Clinical Trials Registry Platform databases were systematically searched for the following keywords: respiratory tract infection, probiotics, viral infection, COVID-19, and clinical trial. A total of 27 clinical trials conducted on 9433 patients with RTI plus 10 ongoing clinical studies of probiotics intervention in Coronavirus disease 2019 (COVID-19) were reviewed. The review looked at the potency of probiotics for the hindrance and/or treatment of RTI diseases, this may also apply to COVID-19. The review found that probiotics could significantly increase the plasma levels of cytokines, the effect of influenza vaccine and quality of life, as well as reducing the titer of viruses and the incidence and duration of respiratory infections. These antiviral and immune-modulating activities and their ability to stimulate interferon production recommend the use of probiotics as an adjunctive therapy to prevent COVID-19. Based on this extensive review of RCTs we suggest that probiotics are a rational complementary treatment for RTI diseases and a viable option to support faster recovery. © 2021 The Author