Selection Shapes the Robustness of Ligand-Binding Amino Acids

The phenotypes of biological systems are to some extent robust to genotypic changes. Such robustness exists on multiple levels of biological organization. We analyzed this robustness for two categories of amino acids in proteins. Specifically, we studied the codons of amino acids that bind or do not bind small molecular ligands. We asked to what extent codon changes caused by mutation or mistranslation may affect physicochemical amino acid properties or protein folding. We found that the codons of ligand-binding amino acids are on average more robust than those of non-binding amino acids. Because mistranslation is usually more frequent than mutation, we speculate that selection for error mitigation at the translational level stands behind this phenomenon. Our observations suggest that natural selection can affect the robustness of very small units of biological organizatio

Comparison of the effectiveness of chlorine, ozone, and photocatalytic disinfection in reducing the risk of antibiotic resistance pollution

Effectiveness of conventional chlorine and ozone disinfection on reduction of antibiotic resistance was compared with less commonly applied heterogeneous photocatalytic process. For this purpose plasmid DNA isolated from a multi-resistant Escherichia coli (E. coli) HB101 was treated in two different concentrations with the three oxidation processes. Oxidative damage on the plasmid DNA was analyzed with gel electrophoresis by comparing the extent of conformational changes in the DNA structure. The effectiveness of the applied oxidant in reducing the risk of resistance transfer was also evaluated by comparing the ability of treated plasmid DNA to transform competent cells. Chlorine did not affect plasmid DNA structure at the studied doses, while ozone and photocatalytic treatment resulted in conformational changes and the damage increased with increasing oxidant doses. Transformation experiments confirmed a similar trend. Chlorine did not affect the transformability and the cell counts of competent cells transformed with chlorine treated plasmid DNA were similar to those transformed by non-treated plasmid DNA in the control experiments

Artificial grammar learning in Williams syndrome and in typical development: the role of rules, familiarity and prosodic cues

Artificial grammar learning (AGL) is an empirical paradigm which investigates basic pattern- and structural processing in different populations. It can inform how higher cognitive functions, such as language use, take place. Our study used AGL to assess how children with Williams syndrome (WS) (n=16) extract patterns in structured sequences of synthetic speech, how they compare to typically developing (TD) children (n=60), and how prosodic cues affect learning. The TD group was divided into: a group whose non-verbal abilities (NVMA) were within the range of the WS group, and a group whose chronological age (CA) was within the range of the WS group. TD children relied mainly on rule-based generalization when making judgements about sequence acceptability, whereas children with WS relied on familiarity with specific stimulus combinations. The TD participants whose NVMA were similar to the WS group, showed less evidence of relying on grammaticality than TD participants whose CA was similar to the WS group. In absence of prosodic cues, the children with WS did not demonstrate evidence of learning. Results suggest that, in WS children, the transition to rule-based processing in language does not keep pace with TD children and may be an indication of differences in neuro-cognitive mechanisms

Dynamic reorganization of the functional brain networks associated with concept learning: a multimodal approach

Concept learning is a lifelong process that starts at the very early days of our lives. An intact concept learning requires extracting and associating the commonalities and distinctions between the set of experiences, events, objects, and facts happening around us in a meaningful way. Extracted commonalities, and semantic features, are used in organizing the information into categorized representations in the brain. In order to encode and store the newly acquired knowledge efficiently, the human brain supports a wealth of cognitive abilities; comprehension, categorization, association, binding, and memory all require establishing new neural pathways across the distinct sensory-motor, memory, and association areas. The human brain is a plastic organ and shows rapid adaptation to changing dynamics and cognitive demands. The brain always seeks to reach a computationally optimum organizational structure to establish efficient information transactions. The efficiency supports the rapid encoding and maintenance of the newly acquired knowledge and accompanying skills across diverse regions of the brain. In this study, by combining the high spatio-temporal power of multimodal imaging, we aimed to capture the fast-changing dynamics of the brain towards an efficient state with learning a set of novel concepts. Benefiting from the high spatio-temporal strength of the EEG and fMRI, we investigated the reorganization of the brain dynamics both at the functional and cortico-electrical levels. By establishing the whole-brain level time-varying connectivity elicited to the online and incidental concept learning, we aimed to investigate the evolution of the brain networks towards an efficient state as the successful acquisition and encoding of the concept knowledge is achieved

Selection shapes the robustness of ligand-binding amino acids

Abstract The phenotypes of biological systems are to some extent robust to genotypic changes. Such robustness exists on multiple levels of biological organization. We analyzed this robustness for two categories of amino acids in proteins. Specifically, we studied the codons of amino acids that bind or do not bind small molecular ligands. We asked to what extent codon changes caused by mutation or mistranslation may affect physicochemical amino acid properties or protein folding. We found that the codons of ligand-binding amino acids are on average more robust than those of non-binding amino acids. Because mistranslation is usually more frequent than mutation, we speculate that selection for error mitigation at the translational level stands behind this phenomenon. Our observations suggest that natural selection can affect the robustness of very small units of biological organization

NeuroCausal Metadata

The data will be downloaded with the specific clinical keywords to narrow down the database into clinical studies. This component will be kept as publically open

Serum N-terminal-pro-B-type natriuretic peptide (NT-pro-BNP) levels in hyperthyroidism and hypothyroidism

WOS: 000252185000001PubMed ID: 18271501Natriuretic peptides represent a novel diagnostic tool in the assessment of heart failure. N-terminal-pro-B-type natriuretic peptide (NT-proBNP), a member of the natriuretic peptid family, is produced and released from cardiac ventricles. Changes in cardiac functions are observed in thyroid dysfunctions. The aim of this study was to assess the changes in serum NT-proBNP levels and to evaluate impact of thyroid hormones on serum NT-proBNP in patients with hyperthyroidism and hypothyroidism. Serum NT-proBNP levels were measured in 21 patients with hyperthyroidism and in 24 patients with hypothyroidism and compared with 20 healthy control subjects. Patients without cardiac disease were included into the study as well. Serum NT-proBNP levels were measured by electrochemiluminescence immunoassay. Serum NT-proBNP levels were higher in hyperthyroid patients than in hypothyroid patients and in control subjects, with mean values of 239.03 +/- 47.33, 45.97 +/- 13.48, 55.57 +/- 13.01 pg/ml, respectively (p < 0.0001). Serum NT-proBNP and thyroid hormones were correlated in all patients. Moreover, there was a significant positive correlation between serum NT-proBNP and serum free T4 (FT4) levels (r = 0,549, p = 0.012) in hyperthyroidic patients. Multiple regression analyses demonstrated that increasing FT4 was independently associated with a high serum NT-proBNP levels, whereas heart rate was not in hyperthyroid patients. Serum NT-proBNP levels are higher in the hyperthyroid state as compared with the hypothyroid and euthyroid state. Thyroid dysfunction affects serum NT-proBNP levels, possibly influencing the secretion of the peptide. Therefore, thyroid function has to be considered when evaluating high serum NT-proBNP levels in patients without cardiac dysfunction

Impact of renal function or folate status on altered plasma homocysteine levels in hypothyroidism

WOS: 000236535900016PubMed ID: 16543681Hyperhomocysteinemia is an independent risk factor for coronary, peripheral and cerebrovascular diseases. Moderately elevated total homocysteine (tHcy) levels have been reported in patients with overt hypothyroidism. Plasma tHcy concentration is affected by several physiological factors and is elevated tinder conditions of impaired folate and cobalamin status and in renal failure. The aim of this Study was to assess plasma tHcy concentrations and to evaluate the role of potential determinants of plasma tHcy levels in hypothyroid patients. Fasting plasma tHcy, serum homocysteine-related vitamins folate and vitamin B-12, serum cystatin C (CysC) and creatinine, were determined in 22 hypothyroid patients and compared with 25 healthy control subjects. Creatinine clearance (CCr) was calculated using the Cockroft-Gault formula. Plasma tHcy levels were determined by HPLC with fluorescence detection and serum CysC by automated particle enhanced immunoturbidimetry. Plasma tHcy, creatinine levels were significantly higher, and serum CysC levels, and creatinine clearance values were lower in hypothyroid patients than in control subjects. Folate levels were lower in hypothyroidic group compared to the control group. There were no differences in vitamin 13, levels between hypothyroid and control groups. Positive correlation was noted between tHcy and creatinine levels in hypothyroid patients (r = 0.596); however, an inverse correlation was found between tHcy and folate levels (r = -0.705) in hypothyroid patients. In conclusion, tHcy was increased in hypothyroidism, and this increase was more strongly associated with changes in serum folate than in serum creatinine and CysC, suggesting an altered folate status

Is there a distinct harbor porpoise subpopulation in the Marmara Sea?

Genetic population structure of geographically isolated endangered Black Sea harbor porpoise (Phocoena phocoena relicta) is little known in Turkish waters, especially in the Turkish Straits System (TSS- Marmara Sea, Bosphorus and Dardanelles), which connects the Black Sea and the Aegean Sea. Mitochondrial DNA sequences of 70 new individuals sampled in the Turkish Black Sea, TSS and Aegean Sea, revealed five new haplotypes from the Black Sea. The findings support the idea that harbor porpoises from the Black Sea dispersed into the Aegean through the TSS. Considering signatures of population expansion, all subpopulations showed a signature of population expansion. The network data and the Phi st calculations indicated that the Marmara Sea subpopulation was significantly differentiated from all of the other subpopulations, and supports the notion of its isolated. The finding of a potential management unit (MU) within an already heavily impacted subpopulation as a whole suggests that the individuals of P. p. relicta inhabiting the Marmara Sea require a very rigorous conservation strategy to ensure the survival of this subpopulation, represented by its unique haplotype