Because compounds accumulate through dry periods and enter aquatic systems in just a few seasonal events such as snowmelt and summer storms, surface waters in semi-arid, cold regions, such as the Canadian Prairies, are particularly vulnerable to loading of contaminant from runoff events from surfaces. This study assessed concentrations of metals and selected trace organics entering a river via surface runoff from an urban region and how these semi-arid regions with large seasonal variations in temperature might differ from more temperate regions. Selected potentially harmful elements (PHEs) including, Mn with Cr, Cu, Zn, Ba and U all exceeded guideline discharge values set by the Canadian Council of the Ministers of the Environment (CCME) by as much as 16-fold. Variation among discharges during spring, summer and winter was observed. For example, across the whole city, an estimated 6 kg of zinc was discharged in a spring storm, 36 kg in a summer storm and 17 tonnes in snowmelt. The mass of Zn discharged is similar to the annual loading estimated for Stockholm, Sweden, but in Saskatoon, Saskatchewan, Canada, the bulk of runoff was during snowmelt. The mean sum of poly- and per-fluoroalkyl substances (PFAS) in stormwater was 9.0 ng L-1, which is consistent with concentrations observed in other Canadian cities (6.5-16 ng L-1). These concentrations of PFAS are likely due to dispersed sources and orders of magnitude less than thresholds for toxicity to fish and aquatic invertebrates.

• MeSH
• chemické látky znečišťující vodu analýza   MeSH
• kovy MeSH
• monitorování životního prostředí MeSH
• roční období MeSH
• teplota MeSH
• velkoměsta MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Saskatchewan MeSH
• Švédsko MeSH
• velkoměsta MeSH

• MeSH
• genderová identita MeSH
• sexualita MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• sexuologie
• NLK Publikační typ
• elektronické časopisy

• MeSH
• nádory hrudníku MeSH
• patologie MeSH

• Konspekt
• Patologie. Klinická medicína

BACKGROUND: Fungal beta-N-acetylhexosaminidases catalyze the hydrolysis of chitobiose into its constituent monosaccharides. These enzymes are physiologically important during the life cycle of the fungus for the formation of septa, germ tubes and fruit-bodies. Crystal structures are known for two monomeric bacterial enzymes and the dimeric human lysosomal beta-N-acetylhexosaminidase. The fungal beta-N-acetylhexosaminidases are robust enzymes commonly used in chemoenzymatic syntheses of oligosaccharides. The enzyme from Aspergillus oryzae was purified and its sequence was determined. RESULTS: The complete primary structure of the fungal beta-N-acetylhexosaminidase from Aspergillus oryzae CCF1066 was used to construct molecular models of the catalytic subunit of the enzyme, the enzyme dimer, and the N-glycosylated dimer. Experimental data were obtained from infrared and Raman spectroscopy, and biochemical studies of the native and deglycosylated enzyme, and are in good agreement with the models. Enzyme deglycosylated under native conditions displays identical kinetic parameters but is significantly less stable in acidic conditions, consistent with model predictions. The molecular model of the deglycosylated enzyme was solvated and a molecular dynamics simulation was run over 20 ns. The molecular model is able to bind the natural substrate - chitobiose with a stable value of binding energy during the molecular dynamics simulation. CONCLUSION: Whereas the intracellular bacterial beta-N-acetylhexosaminidases are monomeric, the extracellular secreted enzymes of fungi and humans occur as dimers. Dimerization of the fungal beta-N-acetylhexosaminidase appears to be a reversible process that is strictly pH dependent. Oligosaccharide moieties may also participate in the dimerization process that might represent a unique feature of the exclusively extracellular enzymes. Deglycosylation had only limited effect on enzyme activity, but it significantly affected enzyme stability in acidic conditions. Dimerization and N-glycosylation are the enzyme's strategy for catalytic subunit stabilization. The disulfide bridge that connects Cys448 with Cys483 stabilizes a hinge region in a flexible loop close to the active site, which is an exclusive feature of the fungal enzymes, neither present in bacterial nor mammalian structures. This loop may play the role of a substrate binding site lid, anchored by a disulphide bridge that prevents the substrate binding site from being influenced by the flexible motion of the loop.

• MeSH
• Aspergillus oryzae enzymologie   MeSH
• beta-N-acetylhexosaminidasy chemie   izolace a purifikace   metabolismus   MeSH
• dimerizace MeSH
• financování organizované MeSH
• glykosylace MeSH
• koncentrace vodíkových iontů MeSH
• konformace proteinů MeSH
• molekulární modely MeSH
• počítačová simulace MeSH
• Ramanova spektroskopie metody   MeSH
• spektroskopie infračervená s Fourierovou transformací metody   MeSH
• stabilita enzymů MeSH

BACKGROUND: Lectins are proteins of non-immune origin capable of binding saccharide structures with high specificity and affinity. Considering the high encoding capacity of oligosaccharides, this makes lectins important for adhesion and recognition. The present study is devoted to the PA-IIL lectin from Pseudomonas aeruginosa, an opportunistic human pathogen capable of causing lethal complications in cystic fibrosis patients. The lectin may play an important role in the process of virulence, recognizing specific saccharide structures and subsequently allowing the bacteria to adhere to the host cells. It displays high values of affinity towards monosaccharides, especially fucose--a feature caused by unusual binding mode, where two calcium ions participate in the interaction with saccharide. Investigating and understanding the nature of lectin-saccharide interactions holds a great potential of use in the field of drug design, namely the targeting and delivery of active compounds to the proper site of action. RESULTS: In vitro site-directed mutagenesis of the PA-IIL lectin yielded three single point mutants that were investigated both structurally (by X-ray crystallography) and functionally (by isothermal titration calorimetry). The mutated amino acids (22-23-24 triad) belong to the so-called specificity binding loop responsible for the monosaccharide specificity of the lectin. The mutation of the amino acids resulted in changes to the thermodynamic behaviour of the mutants and subsequently in their relative preference towards monosaccharides. Correlation of the measured data with X-ray structures provided the molecular basis for rationalizing the affinity changes. The mutations either prevent certain interactions to be formed or allow formation of new interactions--both of afore mentioned have strong effects on the saccharide preferences. CONCLUSION: Mutagenesis of amino acids forming the specificity binding loop allowed identification of one amino acid that is crucial for definition of the lectin sugar preference. Altering specificity loop amino acids causes changes in saccharide-binding preferences of lectins derived from PA-IIL, via creation or blocking possible binding interactions. This finding opens a gate towards protein engineering and subsequent protein design to refine the desired binding properties and preferences, an approach that could have strong potential for drug design.

• MeSH
• bakteriální adheziny genetika   chemie   MeSH
• chromatografie afinitní MeSH
• financování organizované MeSH
• jednonukleotidový polymorfismus MeSH
• konformace proteinů MeSH
• krystalografie rentgenová MeSH
• lektiny genetika   chemie   MeSH
• molekulární modely MeSH
• monosacharidy chemie   MeSH
• mutageneze cílená MeSH
• proteinové inženýrství MeSH
• Pseudomonas aeruginosa genetika   MeSH
• Ralstonia solanacearum chemie   MeSH
• rekombinantní proteiny genetika   izolace a purifikace   MeSH
• rostlinné lektiny chemie   MeSH
• substituce aminokyselin MeSH
• vazebná místa MeSH

The Body Appreciation Scale-2 (BAS-2) is a widely used measure of a core facet of the positive body image construct. However, extant research concerning measurement invariance of the BAS-2 across a large number of nations remains limited. Here, we utilised the Body Image in Nature (BINS) dataset - with data collected between 2020 and 2022 - to assess measurement invariance of the BAS-2 across 65 nations, 40 languages, gender identities, and age groups. Multi-group confirmatory factor analysis indicated that full scalar invariance was upheld across all nations, languages, gender identities, and age groups, suggesting that the unidimensional BAS-2 model has widespread applicability. There were large differences across nations and languages in latent body appreciation, while differences across gender identities and age groups were negligible-to-small. Additionally, greater body appreciation was significantly associated with higher life satisfaction, being single (versus being married or in a committed relationship), and greater rurality (versus urbanicity). Across a subset of nations where nation-level data were available, greater body appreciation was also significantly associated with greater cultural distance from the United States and greater relative income inequality. These findings suggest that the BAS-2 likely captures a near-universal conceptualisation of the body appreciation construct, which should facilitate further cross-cultural research.

• MeSH
• faktorová analýza statistická MeSH
• genderová identita * MeSH
• jazyk (prostředek komunikace) MeSH
• lidé MeSH
• představa o vlastním těle * psychologie   MeSH
• průzkumy a dotazníky MeSH
• psychometrie MeSH
• reprodukovatelnost výsledků MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Body-positive online content (BPOC) has recently become widespread, yet the factors that explain its association with body satisfaction have scarcely been studied. The current study investigates the indirect association between the self-reported frequency of viewing BPOC and body satisfaction through body appreciation and the moderating roles of body-ideal internalization, self-esteem, intentional searching, and gender. Utilizing survey data from 1530 Czech adolescents aged 13-18 (M=15.4, SD=1.7, 50 % girls), the present study found limited support for an indirect connection between the frequency of viewing BPOC and body satisfaction through body appreciation. Nonetheless, an indirect association appeared among adolescents with average and above-average frequencies for intentional searching for BPOC. Other investigated moderating factors were not significant. The present findings suggest that BPOC may be positively associated with body image, but only for those who deliberately search for it. The study highlights the importance of individual moderating factors in the context of BPOC and the remaining research gaps, such as the examination of its various types and aspects and their relationship with body image.

• MeSH
• lidé MeSH
• mladiství MeSH
• obranné mechanismy MeSH
• osobní uspokojení MeSH
• představa o vlastním těle * psychologie   MeSH
• průzkumy a dotazníky MeSH
• sebepojetí * MeSH
• Check Tag
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

The Breast Size Satisfaction Survey (BSSS) was established to assess women's breast size dissatisfaction and breasted experiences from a cross-national perspective. A total of 18,541 women were recruited from 61 research sites across 40 nations and completed measures of current-ideal breast size discrepancy, as well as measures of theorised antecedents (personality, Western and local media exposure, and proxies of socioeconomic status) and outcomes (weight and appearance dissatisfaction, breast awareness, and psychological well-being). In the total dataset, 47.5 % of women wanted larger breasts than they currently had, 23.2 % wanted smaller breasts, and 29.3 % were satisfied with their current breast size. There were significant cross-national differences in mean ideal breast size and absolute breast size dissatisfaction, but effect sizes were small (η2 = .02-.03). The results of multilevel modelling showed that greater Neuroticism, lower Conscientiousness, lower Western media exposure, greater local media exposure, lower financial security, and younger age were associated with greater breast size dissatisfaction across nations. In addition, greater absolute breast size dissatisfaction was associated with greater weight and appearance dissatisfaction, poorer breast awareness, and poorer psychological well-being across nations. These results indicate that breast size dissatisfaction is a global public health concern linked to women's psychological and physical well-being.

• MeSH
• celosvětové zdraví * MeSH
• dospělí MeSH
• lidé MeSH
• nespokojenost s tělem psychologie   MeSH
• osobní uspokojení * MeSH
• prsy * MeSH
• velikost orgánu MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND/AIMS: Growth hormone (GH) could have the potential to improve protein metabolism in sepsis but glutamine deficiency has been reported after GH treatment. The aim was to investigate the effects of glutamine deficiency in sepsis with and without GH treatment on protein and amino acid metabolism. METHODS: Cecal ligation and puncture (CLP) was used as a model of sepsis. Serious glutamine deficiency was induced by administration of glutamine synthetase inhibitor, methionine sulfoximine (MSO). Young Wistar rats were divided into 5 groups: control; CLP; CLP+MSO; CLP+GH, and CLP+MSO+GH. Parameters of protein metabolism were measured on incubated soleus and extensor digitorum longus muscles: [1-14C]leucine was used to estimate protein synthesis and leucine oxidation, tyrosine release was used to evaluate protein breakdown. Amino acid concentrations in plasma, skeletal muscle and incubation media were measured by HPLC. RESULTS/CONCLUSIONS: A reduced muscle glutamine concentration after MSO treatment is not associated with changes in the rates of protein synthesis or breakdown. MSO treatment decreased glutamine release from skeletal muscle and plasma glutamine concentration. Severe glutamine deficiency in GH-treated septic rats resulted in increased release of branched-chain amino acids from skeletal muscle. Copyright 2006 S. Karger AG, Basel.

• MeSH
• aminokyseliny metabolismus   MeSH
• financování organizované MeSH
• glutamin analýza   metabolismus   nedostatek   MeSH
• kosterní svaly metabolismus   MeSH
• krysa rodu rattus MeSH
• náhodné rozdělení MeSH
• potkani Wistar MeSH
• růstový hormon farmakologie   MeSH
• sepse metabolismus   patofyziologie   MeSH
• svalové proteiny metabolismus   MeSH
• vysokoúčinná kapalinová chromatografie metody   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH

AIM: The purpose of our study was to determine urinary iodine as an indicator of iodine supplementation in Roma (Gypsy) neonates compared to majority population neonates. METHODS: The groups studied were formed by 30 full-term Roma neonates and 151 majority population neonates. Iodine was determined from samples of urine collected on the 4th day after delivery, after alkaline ashing, using the Sandell-Kolthoff method. RESULTS: The median of urinary iodine in Roma neonates was 92.15 microg/l urine and in neonates from majority population mothers it was 109.20 microg/l urine. The mean of urinary iodine in Roma neonates was 114.55 microg/l urine (SD 71.68 microg/l) and in neonates from majority population mothers it was 141.86 microg/l urine (SD 87.42 microg/l). The difference was not statistically significant. Majority population mothers more frequently consumed nutrition supplements containing iodine as well as fish. CONCLUSIONS: Compared to older data, supplementation of neonates with iodine is higher. However, it does not reach optimum levels. The urinary iodine median in Roma neonates lies in the mild iodine deficiency band. Copyright 2006 S. Karger AG, Basel.

• MeSH
• dieta MeSH
• dospělí MeSH
• etnicita MeSH
• financování organizované MeSH
• jod aplikace a dávkování   moč   nedostatek   MeSH
• kolorimetrie MeSH
• lidé MeSH
• novorozenec MeSH
• nutriční stav MeSH
• potrava z moře (živočišná) MeSH
• spektrální analýza MeSH
• studie případů a kontrol MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• novorozenec MeSH
• ženské pohlaví MeSH
• Geografické názvy
• Česká republika MeSH