Antimicrobial photodynamic therapy has been proposed as an alternative to suppress subgingival species. This results from the balance among Streptococcus sanguis, Streptococcus mutans and Candida ...albicans in the dental biofilm. Not all the photosensitizers have the same photodynamic effect against the different microorganims. The objective of this study is to compare in vitro the photodynamic effect of methylene blue (MB), rose Bengal (RB) and curcumin (CUR) in combination with white light on the cariogenic microorganism S. mutans, S. sanguis and C. albicans.
Photodynamic therapy with MB, RB and CUR inhibited 6 log 10 the growth of both bacteria but at different concentrations: 0.31-0.62 μg/ml and 0.62-1.25 μg/ml RB were needed to photoinactivate S. mutans and S. sanguis, respectively; 1.25-2.5 μg/ml MB for both species; whereas higher CUR concentrations (80-160 μg/ml and 160-320 μg/ml) were required to obtain the same reduction in S. mutans and S. sanguis viability respectively. The minimal fungicidal concentration of MB for 5 log10 CFU reduction (4.5 McFarland) was 80-160 μg/ml, whereas for RB it ranged between 320 and 640 μg/ml. For CUR, even the maximum studied concentration (1280 μg/ml) did not reach that inhibition. Incubation time had no effect in all experiments.
Photodynamic therapy with RB, MB and CUR and white light is effective in killing S. mutans and S. sanguis strains, although MB and RB are more efficient than CUR. C. albicans required higher concentrations of all photosensitizers to obtain a fungicidal effect, being MB the most efficient and CUR ineffective.
Climate change and plastic pollution are likely the most relevant challenges for the environment in the 21st century. Developing cost-effective technologies for the bioconversion of methane (CH4) ...into polyhydroxyalkanoates (PHAs) could simultaneously mitigate CH4 emissions and boost the commercialization of biodegradable polymers. Despite the fact that the role of temperature, nitrogen deprivation, CH4:O2 ratio or micronutrients availability on the PHA accumulation capacity of methanotrophs has been carefully explored, there is still a need for optimization of the CH4-to-PHA bioconversion process prior to becoming a feasible platform in future biorefineries. In this study, the influence of different cultivation broth pH values (5.5, 7, 8.5 and 10) on bacterial biomass growth, CH4 bioconversion rate, PHA accumulation capacity and bacterial community structure was investigated in a stirred tank bioreactor under nitrogen deprivation conditions. Higher CH4 elimination rates were obtained at increasing pH, with a maximum value of 50.4 ± 2.7 g CH4·m−3·h−1 observed at pH 8.5. This was likely mediated by an increased ionic strength in the mineral medium, which enhanced the gas-liquid mass transfer. Interestingly, higher PHB accumulations were observed at decreasing pH, with the highest PHB contents recorded at a pH 5.5 (43.7 ± 3.4 %w·w−1). The strong selective pressure of low pH towards the growth of Type II methanotrophic bacteria could explain this finding. The genus Methylocystis increased its abundance from 34 % up to 85 and 90 % at pH 5.5 and 7, respectively. On the contrary, Methylocystis was less abundant in the community enriched at pH 8.5 (14 %). The accumulation of intracellular PHB as energy and carbon storage material allowed the maintenance of high CH4 biodegradation rates during 48 h after complete nitrogen deprivation. The results here obtained demonstrated for the first time a crucial and multifactorial role of pH on the bioconversion performance of CH4 into PHA.
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•Low pH (5.5–7.0) is a strong selective pressure towards the growth of Methylocystis.•A higher abundance of Methylocystis entails higher PHA accumulation (>40 %w·w−1).•High pH (8.5) boosts the CH4 degradation performance (>50 g CH4·m−3·h−1).•Very high pH (10) supported a negligible biomass growth and induced cell lysis.•PHA accumulation started immediately after nitrogen deprivation (<10 mg N·L−1).
Deep brain stimulation (DBS) in the subgenual cingulated gyrus (SCG) is a promising new technique that may provide sustained remission in resistant major depressive disorder (MDD). Initial studies ...reported a significant early improvement in patients, followed by a decline within the first month of treatment, an unexpected phenomenon attributed to potential placebo effects or a physiological response to probe insertion that remains poorly understood. Here we characterized the behavioural antidepressant-like effect of DBS in the rat medial prefrontal cortex, focusing on modifications to rodent SCG correlate (prelimbic and infralimbic (IL) cortex). In addition, we evaluated the early outcome of DBS in the SCG of eight patients with resistant MDD involved in a clinical trial. We found similar antidepressant-like effects in rats implanted with electrodes, irrespective of whether they received electrical brain stimulation or not. This effect was due to regional inflammation, as it was temporally correlated with an increase of glial-fibrillary-acidic-protein immunoreactivity, and it was blocked by anti-inflammatory drugs. Indeed, inflammatory mediators and neuronal p11 expression also changed. Furthermore, a retrospective study indicated that the early response of MDD patients subjected to DBS was poorer when they received anti-inflammatory drugs. Our study demonstrates that electrode implantation up to the IL cortex is sufficient to produce an antidepressant-like effect of a similar magnitude to that observed in rats receiving brain stimulation. Moreover, both preclinical and clinical findings suggest that the use of anti-inflammatory drugs after electrode implantation may attenuate the early anti-depressive response in patients who are subjected to DBS.
Abstract
This paper reports the synthesis and electrochemical performance of electrospun polyaniline (PANI) nanofiber membranes that work as high‐performance electrodes in an all‐textile ...supercapacitor (SC). The electrospun separator membrane consists of a mix of polyacrylonitrile (PAN) and poly (ethylene sulfonate) (PES). The all‐textile SC consists of a PES‐PAN membrane, previously soaked in an electrolyte, stacked between two PANI fiber electrodes. Scanning electron microscopy and Fourier‐transform infrared spectroscopy are carried out to characterize the morphology and chemical structure of the PANI and PES‐PAN fiber membranes. Cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy are carried out to characterize the electrochemical properties of the SCs. The all‐textile SC shows very competitive specific capacitances of 275 F/g at 0.25 A/g and a maximum specific power of 1350 Wkg
−1
. These all‐electrospun SCs show higher performance than the SCs using PANI films and commercial cellulose as separators. Finally, we report a flexible all‐electrospun and all‐solid‐state SC was fabricated using flexible substrates and a gel‐type electrolyte. Flexible SC has a specific capacitance of 270 F/g, confirming that the performance of all‐electrospun SCs is a promising approach for future textile energy storage devices for its potential use in wearable devices.
The COVID-19 pandemic is expected to increase suicidal behavior. However, data available to date are inconsistent. This study examines suicidal thoughts and behaviors and suicide trends in 2020 ...relative to 2019 as an approximation to the impact of the pandemic on suicidal behavior and death in the general population of Catalonia, Spain. Data on suicide-related thoughts and behaviors (STBs) and suicidal mortality were obtained from the Catalonia Suicide Risk Code (CSRC) register and the regional police, respectively. We compared the monthly crude incidence of STBs and suicide mortality rates of 2020 with those of 2019. Joinpoint regression analysis was used to assess changes in trends over time during the studied period. In 2020, 4,263 consultations for STBs and 555 suicide deaths were registered in Catalonia (approx. 7.5 million inhabitants). Compared to 2019, in 2020 STBs rates decreased an average of 6.3% (incidence rate ratio, IRR=0.94, 95% CI 0,90–0,98) and overall suicide death rates increased 1.2% (IRR=1.01, 95% CI 0.90–1.13). Joinpoint regression results showed a substantial decrease in STBs rates with a monthly percent change (MPC) of -22.1 (95% CI: -41.1, 2.9) from January-April 2020, followed by a similar increase from April-July 2020 (MPC=24.7, 95% CI: -5.9, 65.2). The most restrictive measures implemented in response to the COVID-19 pandemic reduced consultations for STBs, suggesting that the “stay at home” message may have discouraged people from contacting mental health services. STBs and mortality should continue to be monitored in 2021 and beyond to understand better the mid-to-long term impact of COVID-19 on suicide trends.
We present our statistical study of near-infrared (NIR) variability of X-ray-selected active galactic nuclei (AGNs) in the COSMOS field, using UltraVISTA data. This is the largest sample of AGN light ...curves in YJHKs bands, making it possible to have a global description of the nature of AGNs for a large range of redshifts and for different levels of obscuration. To characterize the variability properties of the sources, we computed the structure function. Our results show that there is an anticorrelation between the structure function A parameter (variability amplitude) and the wavelength of emission and a weak anticorrelation between A and the bolometric luminosity. We find that broad-line (BL) AGNs have a considerably larger fraction of variable sources than narrow-line (NL) AGNs and that they have different distributions of the A parameter. We find evidence that suggests that most of the low-luminosity variable NL sources correspond to BL AGNs, where the host galaxy could be damping the variability signal. For high-luminosity variable NL sources, we propose that they can be examples of "true type II" AGNs or BL AGNs with limited spectral coverage, which results in missing the BL emission. We also find that the fraction of variable sources classified as unobscured in the X-ray is smaller than the fraction of variable sources unobscured in the optical range. We present evidence that this is related to the differences in the origin of the obscuration in the optical and X-ray regimes.
Abstract Kynurenic acid (KYNA) is an endogenous metabolite of the kynurenine pathway for tryptophan degradation and an antagonist of both N-methyl- d -aspartate (NMDA) and alpha-7 nicotinic ...acetylcholine (α7nACh) receptors. KYNA has also been shown to scavenge hydroxyl radicals ( OH) under controlled conditions of free radical production. In this work we evaluated the ability of KYNA to scavenge superoxide anion (O2− ) and peroxynitrite (ONOO− ). The scavenging ability of KYNA (expressed as IC50 values) was as follows: OH = O2− > ONOO− . In parallel, the antiperoxidative and scavenging capacities of KYNA (0–150 μM) were tested in cerebellum and forebrain homogenates exposed to 5 μM FeSO4 and 2.5 mM 3-nitropropionic acid (3-NPA). Both FeSO4 and 3-NPA increased lipid peroxidation (LP) and ROS formation in a significant manner in these preparations, whereas KYNA significantly reduced these markers. Reactive oxygen species (ROS) formation were determined in the presence of FeSO4 and/or KYNA (0–100 μM), both at intra and extracellular levels. An increase in ROS formation was induced by FeSO4 in forebrain and cerebellum in a time-dependent manner, and KYNA reduced this effect in a concentration-dependent manner. To further know whether the effect of KYNA on oxidative stress is independent of NMDA and nicotinic receptors, we also tested KYNA (0–100 μM) in a biological preparation free of these receptors – defolliculated Xenopus laevis oocytes – incubated with FeSO4 for 1 h. A 3-fold increase in LP and a 2-fold increase in ROS formation were seen after exposure to FeSO4 , whereas KYNA attenuated these effects in a concentration-dependent manner. In addition, the in vivo formation of OH evoked by an acute infusion of FeSO4 (100 μM) in the rat striatum was estimated by microdialysis and challenged by a topic infusion of KYNA (1 μM). FeSO4 increased the striatal OH production, while KYNA mitigated this effect. Altogether, these data strongly suggest that KYNA, in addition to be a well-known antagonist acting on nicotinic and NMDA receptors, can be considered as a potential endogenous antioxidant.
•Electrochemical oxidation of NOR using a Sb-doped SnO2 ceramic anode was studied.•The behaviour was compared with that of a BDD anode.•NOR was efficiently oxidized over both anodes tested.•The use ...of a membrane-divided cell showed positive aspects in terms of MCE and COT.•It prevents the intermediate products formed from being reduced on the cathode.
Electrochemical oxidation of Norfloxacin (NOR) in sodium sulphate media has been comparatively studied in an undivided and in a divided electrolytic cell both containing either a boron doped diamond (BDD) or a novel Sb-doped SnO2 ceramic anode under galvanostatic operation. The electro-oxidation was found to occur with first order kinetics mainly when using both anodes. The results showed the great oxidizing power of BDD in relation to the ceramic anode to convert NOR and all the intermediate accumulated into CO2. In the case of the BDD, although a 92% of TOC abatement was achieved, the complete mineralization was not possible probably due to the carboxylic acids still present in solution. On the contrary, for the ceramic electrode, which presented a maximum value of TOC removal of about 63%, the total mineralization of the aromatic oxidation intermediates was not reached under the experimental conditions.
The use of a membrane divided cell showed positive aspects in terms of molecule degradation, degree of mineralization and current efficiency since prevents the intermediate products formed during the NOR oxidation process from being reduced on the cathode.
Aim
To analyse and compare the root canal microbiome present in root‐filled teeth of two different geographical populations, and to study their functional potential using a next‐generation sequencing ...approach.
Methodology
Sequencing data obtained from surgical specimens from previously treated teeth with periapical bone loss from Spain and USA were included in the study. Taxa were classified using SILVA v.138 database. Differences in genera abundances among the 10 most abundant genera were evaluated using a Kruskal–Wallis test. Alpha diversity indices were calculated in mothur. The Shannon and Chao1 indices were used. Analyses of similarity (ANOSIM) to determine differences in community composition were done in mothur, with Bonferroni correction for multiple comparisons. p‐Values < .05 were considered statistically significant. Identification of enriched bacteria function prediction in the study groups (KEGG pathways) was carried out by linear discriminant analysis effect size (LEfSe) via Python 3.7.6.
Results
A greater alpha‐diversity (Shannon and Chao1 indices) was observed from samples obtained in Spain (p = .002). Geography showed no significant effects on community composition via an ANOSIM using Bray–Curtis dissimilarities (R = 0.03, p = .21). Bacterial functional analysis prediction obtained by PICRUSt showed that 5.7% KEGG pathways differed between the Spain and US samples.
Conclusions
The taxonomic assessment alone does not fully capture the microbiome's differences from two different geographical locations. Carbohydrate and amino acid metabolism were enriched in samples from Spain, while samples from USA had a higher representation of pathways related to nitrogen, propanoate metabolism, and secretion systems.
Background: Tissue factor (TF) is the main initiator of the coagulation cascade and elements that may upregulate its expression might provoke thrombotic events. Systemic lupus erythematosus (SLE) and ...antiphospholipid syndrome (APS) are autoimmune diseases characterized by a high TF expression in monocytes. Objectives: To examine the role of microRNAs (miRNAs) in TF expression and to evaluate their levels in SLE and APS patients. Methods: An in silico search was performed to find potential putative binding sites of miRNAs in TF mRNA. In vitro validation was performed transfecting cells expressing TF (THP‐1 and MDA‐MB‐231) with oligonucleotide miRNA precursors and inhibitors. Additionally, reporter assays were performed to test for the binding of miR‐20a to TF mRNA. Levels of miRNAs and TF were measured by quantitative (qRT‐PCR) in patients with APS and SLE. Results: Overexpression of miRNA precursors, but not inhibitors, of two of the members of cluster miR‐17∼92, for example miR‐19b and miR‐20a, in cells expressing TF decreased TF mRNA, protein levels, and procoagulant activity between 30% and 60%. Reporter assays showed that miR‐20a binds to TF mRNA. Finally, we measured levels of miR‐19b and miR‐20a in monocytes from patients with APS and SLE and observed significantly lower miRNAs levels in comparison with healthy subjects inversely correlated with the levels of TF. Conclusions: Down‐regulation of miR‐19b and miR‐20a observed in patients with SLE and APS could contribute to increased TF expression and thus provoke the hypercoagulable state characteristic of these patients.
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