A dynamical system analysis of the development of spontaneous lower extremity movements in newborn and young infants

This study's aim was to evaluate the characteristics of newborn and young infants' spontaneous lower extremity movements by using dynamical systems analysis. Participants were 8 healthy full-term newborn infants (3 boys, 5 girls, mean birth weight and gestational age were 3070.6 g and 39 weeks). A tri-axial accelerometer measured limb movement acceleration in 3-dimensional space. Movement acceleration signals were recorded during 200 s from just below the ankle when the infant was in an active alert state and lying supine (sampling rate 200 Hz). Data were analyzed linearly and nonlinearly. As a result, the optimal embedding dimension showed more than 5 at all times. Time dependent changes started at 6 or 7, and over the next four months decreased to 5 and from 6 months old, increased. The maximal Lyapnov exponent was positive for all segments. The mutual information is at its greatest range at 0 months. Between 3 and 4 months the range in results is narrowest and lowest in value. The mean coefficient of correlation for the x-axis component was negative and y-axis component changed to a positive value between 1 month old and 4 months old. Nonlinear time series analysis suggested that newborn and young infants' spontaneous lower extremity movements are characterized by a nonlinear chaotic dynamics with 5 to 7 embedding dimensions. Developmental changes of an optimal embedding dimension showed a U-shaped phenomenon. In addition, the maximal Lyapnov exponents were positive for all segments (0.79-2.99). Infants' spontaneous movement involves chaotic dynamic systems that are capable of generating voluntary skill movements.     

Oxetanocin—Oxetanose Chemistry: Lewis Acid Promoted Glycosidations of the D-Erythrooxetanose Derivatives

Abstract

Upon treatment of 1-O-acetyl-D-erythrooxetanoses (17a,b and 26) with trimethylsilyl N-benzoyladenine or allyltrimethylsilane in the presence of SnCl₄, the ring expanded products (18, 19 and 29) or the acyclic compounds (27 and 28) were obtained. The reaction mechanism involving a novel ring opening process is discussed.     

The role of fibroblast growth factors on the differentiation of vaginal epithelium of neonatal mice

The uterus and upper 3/5 of the vagina originate from the Müllerian duct; however, these organs show quite distinct characteristics in morphology and function. To investigate factors controlling vaginal epithelial cell differentiation from a single layer of pseudostratified epithelium to a multi-layered stratified epithelium with keratin, we focused on fibroblast growth factors (Fgfs). Transformation related protein 63 (Trp63) expression, a marker of stratified epithelium, increased in the Müllerian vaginal epithelial cells from days 0 to 5, and keratin 14 (Krt14) was expressed from day 5, suggesting that Trp63-negative vaginal epithelial cells can differentiate into Trp63-positive cells after birth. Fgf7 and Fgf10 were localized in the vaginal stroma but their receptor, Fgf receptor 2IIIb (Fgfr2IIIb), was localized in the vaginal epithelium. Both Fgf9 and its receptor, Fgfr2IIIc, were localized in the vaginal epithelium. Vaginae cultured with FGF10 or anti-FGF9 antibody showed stratified epithelium with an intense Krt14 expression; however, an inhibitor of phosphorylation of mitogen-activated protein kinase 1/3 (MAPK1/3) canceled the effect of FGF10 and anti-FGF9 antibody. Thus, Fgf10 stimulates the differentiation of pseudostratified epithelial cells into stratified cells via MAPK1/3 pathway, and Fgf9 inhibits this differentiation in the neonatal mouse vagina.     

Computational investigation of the substrate recognition mechanism of protein D-aspartyl (L-isoaspartyl) O-methyltransferase by docking and molecular dynamics simulation studies and application to interpret size exclusion chromatography data

Unusual amino acid residues such as L-β-aspartyl (Asp), D-α-Asp, and D-β-Asp have been detected in proteins and peptides such as α-crystallin in the lens and β-amyloid in the brain. These residues increase with age, and hence they are associated with age-related diseases. The enzyme protein D-aspartyl (L-isoaspartyl) O-methyltransferase (PIMT) can revert these residues back to the normal L-α-Asp residue. PIMT catalyzes transmethylation of S-adenosylmethionine to L-β-Asp and D-α-Asp residues in proteins and peptides. In this work, the substrate recognition mechanism of PIMT was investigated using docking and molecular dynamics simulation studies. It was shown that the hydrogen bonds of Ser60 and Val214 to the carboxyl group of Asp are important components during substrate recognition by PIMT. In addition, specific hydrogen bonds were observed between the main chains of the substrates and those of Ala61 and Ile212 of PIMT when PIMT recognized L-β-Asp. Hydrophobic interactions between the (n-1) residue of the substrates and Ile212 and Val214 of PIMT may also have an important effect on substrate binding. Volume changes upon substrate binding were also evaluated in the context of possible application to interpretation of size exclusion chromatography data.     

Chemical and Biological O-Demethylation of Rotenone Derivatives

3-O-Demethyl and 2,3-O,O-didemethyl derivatives of natural rotenone (5′β-rotenone), 5′α-rotenone, d-epirotenone (5′β-epirotenone) and 5′α-epirotenone are obtained upon reacting 5′β-rotenone or 5′β-epirotenone with two or three molar equivalents of boron tribromide followed by recyclization of the E-ring using sodium bicarbonate. 3-Methoxy-¹⁴C-5′β-rotenone is prepared in 16% yield by treating 3-O-demethyl-5′β-rotenone with methyl-¹⁴C iodide in the presence of alkali followed by epimerization of the ¹⁴C-5′β-epirotenone byproduct for increased yield of ¹⁴C-5′β-rotenone. 3-O-Demethylation is established as a detoxification mechanism for 5′β-rotenone or for one of its metabolites based on the expiration by mice and rats of 27% and 13%, respectively, of the administered radiocarbon as ¹⁴carbon dioxide.     

Acid and Enzymatic Hydrolysis of an Acidic Polysaccharide from Soy Sauce

Mild acid hydrolysis of an acidic polysaccharide (APS-I) from soy sauce resulted in a degraded polysaccharide (DPS), the mixture of neutral sugar, D-galacturonic acid, its α-1,4-linked homologous di- and trisaccharides, and acidic oligosaccharides containing residues of D-galacturonic acid and L-rhamnose. Besides the above-mentioned sugars, an aldobiouronic acid containing D-xylose moiety was also yielded in the enzymatic hydrolysates with a crude polysaccharidase preparation. However, only a β-l, 4-galactobiose was isolated from the lower molecular fraction of enzymatic digest of APS-I with a typical hemicellulase preparation. DPS containing 83% of D-galacturonic acid was able to be degraded by endo-polygalacturonase, but APS-I was not because of its highly was discussed on the basis of these results, periodate oxidation study.     

Polysaccharides of Soybean Seeds

Partial acid hydrolysate of the “hot-water-extract” fraction of soybean seed polysaccharides contained a homologous series of galacto-oligasaccharides as a major component group. Two of them were isolated by column chromatography. They gave, on methylation followed by acid hydrolysis, 2,3,4,6-tetra-, and 2,3,6-tri-O-methyl D-galactose, and were, therefore, 1,4-linked galacto-di- and trisaccharides, respectively. They were hydrolyzed with human saliva to liberate D-galactose but not with brewer’s yeast. The alditols derived from these oligosaccharides showed infrared absorptions at 885 and 895 cm^?1, respectively. These two results were strong evidences for the presence of β-linkages in the molecules of the oligossacharides. The optical rotation and the melting point of the disaccharide agreed with those of the β-1, 4-linked galactodisaccharide hitherto reported. Thus d-galacto-pyranosyl residues in the arabinogalactan are probably connected mainly by β-1,4-linkage.     

A novel cyclic isomaltooligosaccharide (cycloisomaltodecaose, CI-10) produced by Bacillus circulans T-3040 displays remarkable inclusion ability compared with cyclodextrins

Cyclodextrans (CIs) are cyclic isomaltooligosaccharides and only CI-7, CI-8, and CI-9 were known. CI-7, CI-8, and CI-9, consisting of seven, eight, and nine glucoses, respectively, bound by alpha-(1-->6) linkages, are known to be produced by T-3040 strain of Bacillus circulans. However, we have found, using 13C NMR and mass spectrometry, that this strain also produces CI-10, CI-11 and CI-12. These large CIs are very soluble in water and inhibit the glucan synthesis of glucansucrases to the same degree as do the smaller CIs. The CIs were thought to be poor at forming inclusion complexes with chemical compounds, due to their flexible alpha-(1-->6)-glucosidic structure. Among these six CIs, CI-10 was much better at forming an inclusion complex, and it ability to do so was as good as cyclodextrins, as determined by its ability to stabilize the color of Victoria blue B. Therefore, CI-10 may be the most commercially useful CI.     

Purification and properties of bovine kidney ribonucleases

Two RNases (RNases K1 and K2) were purified from bovine kidney by means of column chromatography on phospho-cellulose, Sephadex G-50, CM-cellulose, heparin-Sepharose, nd agarose-APUP. They were named RNase K1 and RNase K2 in order of elution from the heparin-Sepharose column. The purity of RNase K1 thus obtained was about 90% by SDS-disc electrophoresis. RNase K2 was purified to homogeneity by SDS- and pH 4.3 disc electrophoresis. The yield of RNase K2 was 3.4 mg from 11 kg of kidneys. The antigenic properties of the two bovine renal RNases were studied by Ouchterlony's double diffusion analysis. RNase K1 and RNase A were serologically indistinguishable. RNase K2 did not cross-react immunologically with RNase K1 or RNase A. The molecular weights of these RNases determined by gel-filtration on Sephadex G-50 were 13,400 and 14,600 for RNase K1 and RNase K2, respectively. The pH optima for RNase K1 and RNase K2 were 8.5 and 6.5, respectively. Both RNase K1 and RNase K2 were as acid stable as RNase A. RNase K2 was less heat-stable than RNase K1 and RNase A. Although both renal RNases were pyrimidine nucleotide-specific enzymes, RNase K1 and RNase A were more preferential or cytidylic acid than RNase K2. The chemical composition of RNase K2 was determined. RNase K2, like human urinary RNase Us, contained one tryptophan residue. The N-terminal sequences of RNase K2 and RNase Us were determined by Edman degradation. Rnase K2 had a homologous sequence of about 10 amino acid residues with the sequence of RNase Us, a typical non-secretory RNase, within the N-terminal 30 residues.     

Primary structure of a base non-specific ribonuclease from Rhizopus niveus

The primary structure of a base non-specific ribonuclease from Rhizopus niveus (RNase Rh) was determined by nucleotide sequence analysis of the DNA fragment encoding RNase Rh gene including signal peptide sequence, and amino acid sequence analysis of the peptide obtained from RNase Rh and RNase Rh' (a protease-modified RNase Rh created during the course of purification). The sequence determined was: MKAVLALATLIGSTLASSCSSTA LSCSNSANSDTCCSPEYGLVVLNMQWAPGYGPANAFTLHGLWPDKCSGAYAPSGGCDSN RASSSIASVIKSKDSSLYNSMLTYWPSNQGNNNVFWSHEWSKHGTCVSTYDPDCYDNYE EGEDIVDYFQKAMDLRSQYNVYKAFSSNGITPGGTYTATEMQSAIESYFGAKAKIDCSSG TLSDVALYFYVRGRDTYVITDALSTGSCSGDVEYPTK (the sequence of signal peptide is underlined). The sequence indicates that the homology with the sequence of RNase T2 from A. oryzae with the same base specificity is about 42% and that the sequences around the two histidine residues which are supposed to be involved in the active site are fairly conserved.