Hydrogen peroxide (H2O2) is a key redox intermediate generated within cells. Existing probes for H2O2 have not solved the problem of detection of the ultra-low concentrations of the oxidant: these ...reporters are not sensitive enough, or pH-dependent, or insufficiently bright, or not functional in mammalian cells, or have poor dynamic range. Here we present HyPer7, the first bright, pH-stable, ultrafast, and ultrasensitive ratiometric H2O2 probe. HyPer7 is fully functional in mammalian cells and in other higher eukaryotes. The probe consists of a circularly permuted GFP integrated into the ultrasensitive OxyR domain from Neisseria meningitidis. Using HyPer7, we were able to uncover the details of H2O2 diffusion from the mitochondrial matrix, to find a functional output of H2O2 gradients in polarized cells, and to prove the existence of H2O2 gradients in wounded tissue in vivo. Overall, HyPer7 is a probe of choice for real-time H2O2 imaging in various biological contexts.
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•HyPer7 is an ultrasensitive, ultrafast, and pH-stable indicator for H2O2•Being controlled by the Trx system, H2O2 does not diffuse out from mitochondria•Intensity of the H2O2 gradient associates with the stability of cellular protrusions•H2O2 gradients can be visualized in wounded tissues with HyPer7
Pak et al. have developed HyPer7, a next-generation genetically encoded fluorescent probe for H2O2 detection. Importantly, HyPer7 is resistant to pH changes. Applying HyPer7 to study H2O2 diffusion from the mitochondrial matrix, the authors decipher the topology of H2O2 production by Complex I and visualize oxidant gradients in cell motility and wounded tissue.
The reaction between dithiomalondianilide (N,N'-diphenyldithiomalondiamide) and alkyl 3-aryl-2-cyanoacrylates in the presence of morpholine in the air atmosphere leads to the formation of alkyl ...6-amino-4-aryl-7-phenyl-3-(phenylimino)-4,7-dihydro-3H-1,2dithiolo3,4-b- pyridine-5-carboxylates in 37-72% yields. The same compounds were prepared in 23-65% yields by ternary condensation of aromatic aldehydes, ethyl(methyl) cyanoacetate and dithiomalondianilide. The reaction mechanism is discussed. The structure of ethyl 6-amino-4-(4-methoxyphenyl)-7-phenyl-3-(phenylimino)-4,7-dihydro-3H-1,2dithiolo3,4-bpyridine-5-carboxylate was confirmed by X-ray crystallography. Two of the prepared compounds showed a moderate growth-stimulating effect on sunflower seedlings. Three of the new compounds were recognized as strong herbicide safeners with respect to herbicide 2,4-D in the laboratory and field experiments on sunflower.
Introduction
Previous studies have shown that emotional eating is associated with binge eating disorder, body image disturbances and depression.
Objectives
In this study we wanted to find out if ...there is a relationship between emotional eating and body image and life satisfaction in non-clinical sample.
Methods
The study involved 182 normal participants (153 Female, 29 Male, mean age 22,6 ± 7,3), which were recruited in Moscow, Russia. Emotional eating was measured by the opposite pole of Eating for Physical Rather Than Emotional Reasons subscale of Intuitive Eating Scale-2 (IES-2), body image was measured by Multidimensional Body-Self Relations Questionnaire (MBSRQ), Satisfaction with Life Scale (SWLS) was used to measure the corresponding construct. Correlation analysis was performed in IBM SPSS Statistics 22.0.
Results
Emotional eating was associated with the following MBSRQ subscales: lower appearance evaluation (-0,431, p<0,0001), lower body areas satisfaction (-0,335, p<0,0001), as well as lower fitness evaluation (-0,208, p=0,005) and lower health evaluation (-0,182, p=0,014), but higher overweight preoccupation (0,279, p=0,0001) and overestimation of body weight (0,362, p<0,0001). It was also connected to lower satisfaction with life (-0,195, p=0,008).
Conclusions
The results of the study allow us to conclude that emotional eating may pose risks to psychological health of a normal individual. It was shown that emotional eating is connected to negative evaluation of one`s body appearance, fitness and health state, weight and shape concerns, and even to the lower level of satisfaction with one’s life.
Introduction
Recent studies showed that stress and anxiety increased during the Covid-19 pandemic (Bäuerle et al., 2020; Salari et al., 2020). It is important to identify factors which are related to ...this increase.
Objectives
In present study we investigated how perceived value threat of Covid-19 is related to anxiety and depression symptoms in April – May 2020 during the lockdown in Russia.
Methods
Three hundred and four participants were recruited online (M
age
=33.18, SD=13.33, 108 males, 194 females). Participants completed the Short Schwartz’s Value Survey (SSVS; Lindeman & Verkasalo, 2010). They were next asked to rate how likely their values could be threatened because of the Covid-19. They also completed the State-Trait Anxiety Inventory (Spielberger, 1983) and Beck Depression Inventory-II (Beck et al., 1996).
Results
A multiple linear regression model was built to assess how own values and values threatened by Covid-19 explain state anxiety during the lockdown. Threat to openness values was positively related to state anxiety (b=1.07, SE=.49, β=.13, p=.032). Threat to conservation values was only marginally related to state anxiety (b=1.03, SE=.58, β=.13, p=.074). The effects of self-enhancement and self-transcendence values were not significant.
Conclusions
When Covid-19 is perceived as a threat to openness to change values – hedonism, stimulation and self-direction – people experience higher level of anxiety symptoms. Interestingly, perceived threat of Covid-19 to security, conformity and tradition was only marginally related to anxiety. Future studies might explore how encouraging people to fulfill their openness to change values in a safe mode might decrease the level of anxiety.
Introduction
It is known that negative body image can cause significant emotional distress for an individual and thus lead to lower subjective well-being. Previous research has shown that both ...disordered eating and body mass are connected to negative body image.
Objectives
To examine how disordered eating and BMI can predict different aspects of body image.
Methods
A sample of 180 healthy respondents (152 Female, 28 Male, mean age 22,62±7,35) were recruited in Moscow. Disordered eating was measured by Eating Attitude Test (EAT-26; Garner D. et al., 1982), body image was measured by Multidimensional Body-Self Relations Questionnaire (MBSRQ; Cash T. F., 1990). Body mass index (BMI) was calculated on the basis of self-reported data (height and weight). Multiple linear regression analysis was performed in IBM SPSS Statistics 22.0.
Results
Regression model with both predictors determined self-classified weight (SCW; R
2
=0,569, p<0,0001), overweight preoccupation (OWP; R
2
=0,497, p<0,0001), body areas satisfaction (BASS; R
2
=0,259, p<0,0001), and appearance evaluation (R
2
= 0,229, p<0,0001), but only disordered eating symptoms predicted appearance (R
2
= 0,193, p<0,0001) and health (R
2
= 0,036, p<0,05) orientation, and none of the predictors affected fitness or health evaluation and fitness orientation.
Conclusions
Symptoms of disordered eating and body mass index in normal population can predict self-evaluation of one`s appearance as less attractive, body size as bigger and weight as heavier. Only symptoms of disordered eating predicted higher extent of investment in one’s appearance and health. And neither IBM, nor disordered eating predicted self-evaluation of one`s health and fitness or the extent of investment in fitness.
Introduction
People with mental disorder can share negative stereotypes, related to mental disorders. This might cause self-stigmatization, which is negatively related to quality of life and ...compliance with treatment. This self-stigmatization can be non-conscious or implicit, which might complicate it detection and further therapy.
Objectives
In present study we investigated the role of values in implicit self-stigmatization among 40 women diagnosed with schizophrenia (mean age 23.77 years ±6).
Methods
Participants completed the Portrait Value Questionnaire (Schwartz, 2003) and two brief implicit association tests (BIAT), measuring implicit self-esteem and attitudes towards mental disorders (Corrigan et al., 2010). The results of two BIATs were combined as a measure of implicit self-stigmatization.
Results
A linear regression model was built. Four values (self-enhancement, self-transcendence, openness to change and conservation values) were entered as independent variables, while implicit self-stigmatization – as dependent variable. It was found that self-transcendence values were marginally negatively related to implicit self-stigmatization (b=-.122, β=-.398, SE=.064, p=.067), while other values were not significantly related to it (ps>.125).
Conclusions
Self-transcendence values – values related to the well-being of others, which include tolerance, altruism and protection for the welfare of all people and for nature – are negatively related to implicit or non-conscious self-stigmatization. This finding, although marginally significant, is in line with previous studies. Previous studies showed that self-transcendence values are also negatively associated with explicit or conscious self-stigmatization (Lannin et al., 2020). Thus, these values can be targets for programs which aim to decrease self-stigmatization tendencies among patients with mental illness.
Bioinformatics analysis of the sequences of orthologous zinc-containing peptidases of the M15_C subfamily revealed the presence of a conserved tryptophan residue near the active site, which is not ...involved in the formation of the protein core. Site-directed mutagenesis of this Trp114/109 residue using two representatives of the family, l-alanoyl-d-glutamate peptidases of bacteriophages T5 (calcium-activated EndoT5) and RB49 (EndoRB49, without ion regulation) as examples, and further analysis of the 1H NMR spectra of the mutants showed that a decrease in the volume of the W → F → A residue leads to changes in the hydrophobic core and active center of the protein, and also decreases the affinity for regulatory Ca2+ in the EndoT5 mutants. The inactive T5W114A mutant lacks the ability to bind the substrate. In general, the conserved Trp114/109 residue, due to the spatial restrictions of its side chain, significantly affects the formation of the catalytically active form of the enzyme and is critical for catalysis.
Fullerene is a nanosized carbon structure with potential drug delivery applications. We studied the bioeffects of a water-soluble fullerene derivative, fullerenol, with 10-12 oxygen groups (F10-12); ...its structure was characterized by IR and XPS spectroscopy. A bioluminescent enzyme system was used to study toxic and antioxidant effects of F10-12 at the enzymatic level. Antioxidant characteristics of F10-12 were revealed in model solutions of organic and inorganic oxidizers. Low-concentration activation of bioluminescence was validated statistically in oxidizer solutions. Toxic and antioxidant characteristics of F10-12 were compared to those of homologous fullerenols with a higher number of oxygen groups:F24-28 and F40-42. No simple dependency was found between the toxic/antioxidant characteristics and the number of oxygen groups on the fullerene’s carbon cage. Lower toxicity and higher antioxidant activity of F24-28 were identified and presumptively attributed to its higher solubility. An active role of reactive oxygen species (ROS) in the bioeffects of F10-12 was demonstrated. Correlations between toxic/antioxidant characteristics of F10-12 and ROS content were evaluated. Toxic and antioxidant effects were related to the decrease in ROS content in the enzyme solutions. Our results reveal a complexity of ROS effects in the enzymatic assay system.
Thermogenetics is a promising innovative neurostimulation technique, which enables robust activation of neurons using thermosensitive transient receptor potential (TRP) cation channels. Broader ...application of this approach in neuroscience is, however, hindered by a limited variety of suitable ion channels, and by low spatial and temporal resolution of neuronal activation when TRP channels are activated by ambient temperature variations or chemical agonists. Here, we demonstrate rapid, robust and reproducible repeated activation of snake TRPA1 channels heterologously expressed in non-neuronal cells, mouse neurons and zebrafish neurons in vivo by infrared (IR) laser radiation. A fibre-optic probe that integrates a nitrogen-vacancy (NV) diamond quantum sensor with optical and microwave waveguide delivery enables thermometry with single-cell resolution, allowing neurons to be activated by exceptionally mild heating, thus preventing the damaging effects of excessive heat. The neuronal responses to the activation by IR laser radiation are fully characterized using Ca
imaging and electrophysiology, providing, for the first time, a complete framework for a thermogenetic manipulation of individual neurons using IR light.
The current study evaluates the role of reactive oxygen species (ROS) in bioeffects of magnetite nanoparticles (MNPs), such as bare (Fe3O4), humic acids (Fe3O4-HA), and 3-aminopropyltriethoxysilane ...(Fe3O4-APTES) modified MNPs. Mössbauer spectroscopy was used to identify the local surrounding for Fe atom/ions and the depth of modification for MNPs. It was found that the Fe3O4-HA MNPs contain the smallest, whereas the Fe3O4-APTES MNPs contain the largest amount of Fe2+ ions. Bioluminescent cellular and enzymatic assays were applied to monitor the toxicity and anti-(pro-)oxidant activity of MNPs. The contents of ROS were determined by a chemiluminescence luminol assay evaluating the correlations with toxicity/anti-(pro-)oxidant coefficients. Toxic effects of modified MNPs were found at higher concentrations (>10−2 g/L); they were related to ROS storage in bacterial suspensions. MNPs stimulated ROS production by the bacteria in a wide concentration range (10−15−1 g/L). Under the conditions of model oxidative stress and higher concentrations of MNPs (>10−4 g/L), the bacterial bioassay revealed prooxidant activity of all three MNP types, with corresponding decay of ROS content. Bioluminescence enzymatic assay did not show any sensitivity to MNPs, with negligible change in ROS content. The results clearly indicate that cell-membrane processes are responsible for the bioeffects and bacterial ROS generation, confirming the ferroptosis phenomenon based on iron-initiated cell-membrane lipid peroxidation.
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