Effect of music on the latency of recognition of even and odd numbers

The influence of music of a specified intensity on the latency of recognition of even and odd numbers with the involvement of the left and the right hands, respectively, has been studied. Musical accompaniment decreases the latency of recognition to a greater extent if the left hand is involved. Apparently, this is related to the activating influence of music on the right hemisphere in persons who are not professional musicians. The increase in the efficiency of recognition caused by musical accompaniment is considered to be an expression of the dominant principle.     

Enzymatic and chemical methods for the generation of pure hyaluronan oligosaccharides with both odd and even numbers of monosaccharide units

Hyaluronan oligosaccharides display physiological activities not associated with the polymer and are widely used to characterize hyaluronan-binding proteins. They can also be used as biocompatible starting blocks for chemical derivatization. Here we present methods for generating milligram quantities of unusual odd- and even-numbered oligosaccharides, greatly increasing the diversity of reagents for use in such studies. These methods are based upon protocols from the 1960s, at which time it was very difficult to assess the stereochemical purity of the products. To address this, products were analyzed with modern high-field nuclear magnetic resonance spectroscopy. Alkaline beta-elimination conditions previously used to remove reducing-terminal N-acetylglucosamine residues in fact introduce a significant ( approximately 30%) level of stereoisomerism in the products by alkali-catalyzed keto-enol tautomerizations. Milder alkaline conditions were used to overcome this problem, reducing the contamination to <5%. The elimination by-products from this reaction were isolated and characterized, allowing the mechanism of alkaline degradation of hyaluronan to be investigated for the first time. beta-Glucuronidase was used to remove nonreducing-terminal glucuronic acid residues from oligosaccharides. Odd-numbered oligosaccharides with terminal glucuronic acid residues isolated from hyaluronidase digests are shown to originate from acid-catalyzed acetal hydrolysis during boiling denaturation and also have significant levels of stereochemical impurities.     

Effect of constituting amino acid residue numbers on molecularly imprinted chiral recognition sites

In the present study, the effect of constituting amino acid residue numbers of oligopeptide derivatives, which are candidate materials to construct molecular recognition sites, on chiral recognition ability was investigated. Chiral recognition sites were formed from oligopeptide derivatives, of which constituting amino acid residue numbers were three to six, by adopting an alternative molecular imprinting. It was made clear that the number four, in other words, the tetrapeptide derivative, is the best candidate material to form a chiral recognition site.     

Comparison of emotion recognition from facial expression and music

The recognition of basic emotions in everyday communication involves interpretation of different visual and auditory clues. The ability to recognize emotions is not clearly determined as their presentation is usually very short (micro expressions), whereas the recognition itself does not have to be a conscious process. We assumed that the recognition from facial expressions is selected over the recognition of emotions communicated through music. In order to compare the success rate in recognizing emotions presented as facial expressions or in classical music works we conducted a survey which included 90 elementary school and 87 high school students from Osijek (Croatia). The participants had to match 8 photographs of different emotions expressed on the face and 8 pieces of classical music works with 8 offered emotions. The recognition of emotions expressed through classical music pieces was significantly less successful than the recognition of emotional facial expressions. The high school students were significantly better at recognizing facial emotions than the elementary school students, whereas girls were better than boys. The success rate in recognizing emotions from music pieces was associated with higher grades in mathematics. Basic emotions are far better recognized if presented on human faces than in music, possibly because the understanding of facial emotions is one of the oldest communication skills in human society. Female advantage in emotion recognition was selected due to the necessity of their communication with the newborns during early development. The proficiency in recognizing emotional content of music and mathematical skills probably share some general cognitive skills like attention, memory and motivation. Music pieces were differently processed in brain than facial expressions and consequently, probably differently evaluated as relevant emotional clues.     

Structure of even/odd trinucleotide repeat sequences modulates persistence of non-B conformations and conversion to duplex

Expansion of trinucleotide repeats (TNR) has been implicated in the emergence of neurodegenerative diseases. Formation of non-B conformations such as hairpins by these repeat sequences during DNA replication and/or repair has been proposed as a contributing factor to expansion. In this work we employed a combination of fluorescence, chemical probing, optical melting, and gel shift assays to characterize the structure of a series of (CTG)(n) sequences and the kinetic parameters describing their interaction with a complementary sequence. Our structure-based experiments using chemical probing reveal that sequences containing an even or odd number of CTG repeats adopt stem-loop hairpins that differ from one another by the absence or presence of a stem overhang. Furthermore, we find that this structural difference dictates the rate at which the TNR hairpins convert to duplex with a complementary CAG sequence. Indeed, the rate constant describing conversion to (CAG)(10)/(CTG)(n) duplex is slower for sequences containing an even number of CTG repeats than for sequences containing an odd number of repeats. Thus, when both the CAG and CTG hairpins have an even number of the repeats, they display a longer lifetime relative to when the CTG hairpin has an odd number of repeats. The difference in lifetimes observed for these TNR hairpins has implications toward their persistence during DNA replication or repair events and could influence their predisposition toward expansion. Taken together, these results contribute to our understanding of trinucleotide repeats and the factors that regulate persistence of hairpins in these repetitive sequences and conversion to canonical duplex.     

乙酰唑胺对氧惊厥潜伏期的影响

为探讨脑血流调节与氧惊厥的关系,在复制大鼠氧惊厥模型的基础上,采用行为学方法测定氧惊厥潜伏期,并测定不司部位脑组织氧化与抗氧化指标,采用腹腔注射不同剂量脑血管扩张药物乙酰唑胺,观察脑血管扩张对氧化状态以及氧惊厥潜伏期的影响。观察结果为:(1)与生理盐水组相比,乙酰唑胺200、20 mg/kg体重组腹腔给药后氧惊厥潜伏期(纯氧6 ATA暴露)明显缩短(P<0.01),乙酰唑胺2 mg/kg体重组无明显改变(P>0.05);(2)腹腔给乙酰唑胺(20 mg/kg体重)或生理盐水后,各组各部位脑组织GSH-PX无显著差异(P>0.05),但随暴露时间的延长,其活力呈现先升高后降低的趋势;与对照组相比,乙酰唑胺6min组和生理盐水16min组皮层丙二醛(maleic dialdehyde,MDA)含量均明显增多(P<0.01),乙酰唑胺16 min组海马MDA含量明显增多(P<0.01)。结果表明,乙酰唑胺可缩短氧惊厥潜伏期,加重脑组织氧化损伤。     

Effect of music on motor reaction time and interhemispheric relations

Influence of music on motor reaction time (RT) was studied. Warning and triggering stimuli were presented either in the left or in the right visual fields. RT was recorded when playing classical or variety music; control sessions were not accompanied by music. Music shortened RT, and its stimulating effect was the stronger the longer were the initial RTs without music. The influence of variety music was more effective than of the classic one. RT was shortened more when the triggering stimulus was presented in the left visual field. This phenomenon is considered to be an evidence of predominant influence of music on the right cerebral hemisphere due to greater activation from emotional structures.     

Base stacking and even/odd behavior of hairpin loops in DNA triplet repeat slippage and expansion with DNA polymerase

Repetitions of CAG or CTG triplets in DNA can form intrastrand hairpin loops with combinations of normal and mismatched base pairs that easily rearrange. Such loops may promote primer-template slippage in DNA replication or repair to give triplet-repeat expansions like those associated with neurodegenerative diseases. Using self-priming sequences (e.g. (CAG)(16)(CTG)(4)), we resolve all hairpin loops formed and measure their slippage and expansion rates with DNA polymerase at 37 degrees C. Comparing CAG/CTG loop structures with GAC/GTC structures, having similar hydrogen bonding but different base stacking, we find that CAG, CTG, and GTC triplets predominantly form even-membered loops that slip in steps of two triplets, whereas GAC triplets favor odd-numbered loops. Slippage rates decline as hairpin stability increases, supporting the idea that slippage initiates more easily in less stable regions. Loop stabilities (in low salt) increase in the order GTC < CAG < GAC < CTG, while slippage rates decrease in the order GTC > CAG approximately GAC > CTG. Loops of GTC compared with CTG melt 9 degrees C lower and slip 6-fold faster. We interpret results in terms of base stacking, by relating melting temperature to standard enthalpy changes for doublets of base pairs and mispairs, considering enthalpy-entropy compensation.     

Effect of mercurial compounds on structure-linked latency of lysosomal hydrolases

1. A partially purified lysosomal preparation was obtained from adult mouse livers by sucrose-density-gradient centrifugation of a large-granule fraction. 2. This lysosome-enriched subfraction was contaminated approx. 10% by mitochondrial cytochrome c oxidase and malate dehydrogenase. 3. Free acid phosphohydrolase and beta-glucuronidase contributed less than 10% of the total (Triton X-100-solubilized) activity in contrast with approx. 30% free N-acetyl-beta-d-glucosaminidase when assayed in an iso-osmotic incubation system. 4. Exposure of the lysosomal preparation to inorganic Hg(2+) ions and organic mercurials (p-chloromercuribenzoate, phenylmercuric acetate) induced an irreversible loss of structure-linked latency with resulting enzyme activation. 5. Maximal activation was related to log [Hg(2+)] and pH. The response was all-or-none for individual particles; the dose-response curve portrayed the variation in particle resistance within the lysosomal population. 6. l-Cysteine and GSH totally prevented Hg(2+) ion-induced hydrolase activation. Ascorbate provided approx. 50% protection. 7. The three lysosomal hydrolases were differentially activated at constant [Hg(2+)], suggesting a different pattern of binding, unique for each enzyme studied.     

The human EEG in recognition of noisy visual images accompanied by music

The recognition of noisy visual images (Arabic numerals) carried out under the conditions of recognition accompanied by classical or rock music of a specified power improves the recognition. When music-accompanied recognition of visual images is carried out, the structure of coherent relations (their number and significance level) observed during recognition without musical accompaniment is activated and the left-sided asymmetry of the coherence values is also retained (instead of the right-sided asymmetry, which appears in response to music alone). In other words, when the recognition dominant is formed at the behavioral level, changes in the spatial organization of the neocortical electrical processes also seem to follow the dominant principle.     

Interhemispheric EEG interrelations in recognition of masked visual images accompanied by music

Changes in the EEG depend on the style of accompanying music. Classical music produces more patterns with increased diagonal coherences in the γ frequency band, where two foci of integration are formed at points T ₄ and T ₆. During listening to rock music, a larger proportion of all changes occurred in the θ-and α₁ frequency bands; an integration focus was formed at point T ₆ in the α₁ and γ frequency bands. An increase in diagonal coherences that was observed during the recognition was especially pronounced in the Δ-, θ-and α₁ frequency bands. In addition, there was an increase in the coherence between the potentials recorded at points O ₁-P ₄ and O ₂-F ₇, and it was observed in all the frequency bands. During the recognition of masked visual images accompanied by classical or rock music, there were more patterns with an increased diagonal coherence of the currently dominant activity. Before erroneous recognition, a widely generalized increase in coherence over the brain cortex was observed in the Δ, θ, and α₁ bands, which was an informative indicator of the subsequent erroneous recognition. In tests with recognition unaccompanied by music, as well as with music, the main change in symmetrical coherences was either a decrease in or an absence of changes in this indicator versus the background value.     

Effect of negative air ions on morphine-induced changes in the latency of the tail-flick reflex

Adult male Long-Evans rats were exposed to negatively charged air ions at high concentrations (7 x 10(5)/cm3) for six days. Sham-exposed rats were treated identically except that the source of ions was not activated. At the end of the exposure, the latency of the tail-flick reflex was measured in each rat before and 30 and 60 min after an injection of morphine sulphate. The tail-flick reflex was initiated by thermal stimulation. Two heat settings were employed, the lower considered to impart a submaximal and the higher a maximal thermal stimulus. Three morphine doses were tested: 0.5, 1.0, and 1.5 mg/kg. Statistically significant differences between ion-exposed and sham-exposed rats were observed in tail-flick latencies 30 min after the administration of the two lower doses, but not after the highest dose of morphine sulphate. These differences were found at both intensities of thermal stimulation. Tail-flick latencies measured in each group prior to morphine injection were not affected by negative-ion exposure. The data indicate that exposure of rats to negative air ions tends to inhibit the action of morphine on the latency of the tail-flick reflex at morphine doses below 1.0 mg/kg.