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91.
Shinya Fujii Hama Watanabe Hiroki Oohashi Masaya Hirashima Daichi Nozaki Gentaro Taga 《PloS one》2014,9(5)
Dancing and singing to music involve auditory-motor coordination and have been essential to our human culture since ancient times. Although scholars have been trying to understand the evolutionary and developmental origin of music, early human developmental manifestations of auditory-motor interactions in music have not been fully investigated. Here we report limb movements and vocalizations in three- to four-months-old infants while they listened to music and were in silence. In the group analysis, we found no significant increase in the amount of movement or in the relative power spectrum density around the musical tempo in the music condition compared to the silent condition. Intriguingly, however, there were two infants who demonstrated striking increases in the rhythmic movements via kicking or arm-waving around the musical tempo during listening to music. Monte-Carlo statistics with phase-randomized surrogate data revealed that the limb movements of these individuals were significantly synchronized to the musical beat. Moreover, we found a clear increase in the formant variability of vocalizations in the group during music perception. These results suggest that infants at this age are already primed with their bodies to interact with music via limb movements and vocalizations. 相似文献
92.
93.
Shinji Hama Ayumi Yoshida Kazunori Nakashima Hideo Noda Hideki Fukuda Akihiko Kondo 《Applied microbiology and biotechnology》2010,87(2):537-543
The cell surface engineering system, in which functional proteins are genetically displayed on microbial cell surfaces, has
recently become a powerful tool for applied biotechnology. Here, we report on the surfactant modification of surface-displayed
lipase to improve its performance for enzymatic synthesis reactions. The lipase activities of the surfactant-modified yeast
displaying Rhizopus oryzae lipase (ROL) were evaluated in both aqueous and nonaqueous systems. Despite the similar lipase activities of control and
surfactant-modified cells in aqueous media, the treatment with nonionic surfactants increased the specific lipase activity
of the ROL-displaying yeast in n-hexane. In particular, the Tween 20-modified cells increased the cell surface hydrophobicity significantly among a series
of Tween surfactants tested, resulting in 8–30 times higher specific activity in organic solvents with relatively high log
P values. The developed cells were successfully used for the enzymatic synthesis of phospholipids and fatty acid methyl esters
in n-hexane, whereas the nontreated cells produced a significantly low yield. Our results thus indicate that surfactant modification
of the cell surface can enhance the potential of the surface-displayed lipase for bioconversion. 相似文献
94.
95.
Release of the lipopolysaccharide deacylase PagL from latency compensates for a lack of lipopolysaccharide aminoarabinose modification-dependent resistance to the antimicrobial peptide polymyxin B in Salmonella enterica 下载免费PDF全文
Salmonella enterica modifies its lipopolysaccharide (LPS), including the lipid A portion, to adapt to its environments. The lipid A 3-O-deacylase PagL exhibits latency; deacylation of lipid A is not usually observed in vivo despite the expression of PagL, which is under the control of a two-component regulatory system, PhoP-PhoQ. In contrast, PagL is released from latency in pmrA and pmrE mutants, both of which are deficient in aminoarabinose-modified lipid A, although the biological significance of this is not clear. The attachment of aminoarabinose to lipid A decreases the net anionic charge at the membrane's surface and reduces electrostatic repulsion between neighboring LPS molecules, leading to increases in bacterial resistance to cationic antimicrobial peptides, including polymyxin B. Here we examined the effects of the release of PagL from latency on resistance to polymyxin B. The pmrA pagL and pmrE pagL double mutants were more susceptible to polymyxin B than were the parental pmrA and pmrE mutants, respectively. Furthermore, introduction of the PagL expression plasmid into the pmrA pagL double mutant increased the resistance to polymyxin B. In addition, PagL-dependent deacylation of lipid A was observed in a mutant in which lipid A could not be modified with phosphoethanolamine, which partly contributes to the PmrA-dependent resistance to polymyxin B. These results, taken together, suggest that the release of PagL from latency compensates for the loss of resistance to polymyxin B that is due to a lack of other modifications to LPS. 相似文献
96.
Junji Watanabe Victor Grijalva Susan Hama Karen Barbour Franklin G. Berger Mohamad Navab Alan M. Fogelman Srinivasa T. Reddy 《The Journal of biological chemistry》2009,284(27):18292-18301
Hemoglobin (Hb) uniquely associates with proinflammatory HDL in atherogenic mice and coronary heart disease (CHD) patients. In this paper, we report that Hb and its scavenger proteins, haptoglobin (Hp) and hemopexin (Hx) are significantly increased in apoA-1-containing particles of HDL both in mouse models of hyperlipidemia and in CHD patients, when compared with wild type mice and healthy donors, respectively. We further demonstrate that the association of Hb, Hp, and Hx proteins with HDL positively correlates with inflammatory properties of HDL and systemic inflammation in CHD patients. Interestingly, HDL from Hp−/− mice under atherogenic conditions does not accumulate Hb and is anti-inflammatory, suggesting that (i) Hp is required for the association of Hb with HDL and (ii) Hb·Hp complexes regulate the inflammatory properties of HDL. Moreover, treatment of apoE−/− mice with an apoA-1 mimetic peptide resulted in significant dissociation of Hb·Hp complexes from HDL and improvement of HDL inflammatory properties. Our data strongly suggest that HDL can become proinflammatory via the Hb·Hp pathway in mice and humans, and dissociation of Hb·Hp·Hx complexes from apoA-1-containing particles of HDL may be a novel target for the treatment of CHD.Atherosclerosis is the leading cause of morbidity and mortality in Western society. The inverse relationship between HDL2 cholesterol and the risk of atherosclerosis is well established. Although HDL cholesterol is an epidemiological predictor of risk for coronary heart disease (CHD) (1), a significant number of CHD events occur in patients with normal LDL and HDL cholesterol levels (1, 2). Based on a number of recent studies in both animal models and human samples, it appears that the anti- or proinflammatory nature of HDL may be a more sensitive indicator of the presence or absence of atherosclerosis than HDL cholesterol levels. HDL exerts anti-inflammatory functions by promoting reverse cholesterol transport and preventing the oxidation of LDL (3, 4). We have previously shown that the anti-inflammatory functions of HDL can be impaired in humans (5) rabbits (6), and mice (7) during inflammatory processes. This impaired HDL is proinflammatory in nature, as characterized by (i) decreased levels and activity of anti-inflammatory, antioxidant factors, including apolipoprotein A1 (apoA-1) and PON1 (paraoxonase 1) (8); (ii) gain of proinflammatory proteins, such as serum amyloid A and ceruloplasmin (6); (iii) increased lipid hydroperoxide (LOOH) content (9); (iv) reduced potential to efflux cholesterol (10); and (v) diminished ability to prevent LDL oxidation (11). The molecular changes and mechanisms that promote anti-inflammatory HDL conversion to proinflammatory HDL are currently not well understood.We recently reported the identification and characterization of Hb associated with proinflammatory HDL in atherogenic/hyperlipidemic mice and in human CHD patients (12). We demonstrated that under normal circumstances, a small amount of Hb is always found outside of red blood cells (RBC) in the non-lipoprotein fractions of serum (on the order of 10 μm compared with the >1 m concentration of Hb in RBC). We further demonstrated that under conditions of hyperlipidemia in mice and in CHD patients, the non-RBC Hb moves out of the non-lipoprotein fractions and associates with HDL. This HDL-associated Hb was shown to play an important role in the modulation of HDL function, suggesting that Hb is not only a novel biomarker but may also serve as a therapeutic target for atherosclerosis (12). We therefore sought to determine the molecular mechanisms that play a role in the association of Hb with HDL.Hp and Hx are plasma proteins with the highest binding affinity for Hb (Kd ≈ 1 pm) and heme (Kd < 1 pm), respectively. They are expressed mainly in the liver and belong to the family of acute phase proteins, whose synthesis is induced during inflammatory processes (13, 14). Under conditions of increased hemolysis, Hb becomes highly toxic because of the oxidative properties of heme, which participates in the Fenton reaction to produce reactive oxygen species causing cell injury (15). Under these conditions, Hb is known to be scavenged by Hp·Hx complexes that utilize specific receptor pathways, thus protecting the body against the harmful effects of excess free Hb. We set out to determine whether the Hb·Hp·Hx system (i) also participates in the association of Hb with proinflammatory HDL and (ii) plays a role in the inflammatory properties of HDL.In this paper, we demonstrate that (i) Hb·Hp·Hx complexes associate with HDL in CHD patients and mouse models of hyperlipidemia but not in healthy human donors and wild type mice, and (ii) Hb·Hp·Hx association with HDL positively correlates with proinflammatory properties of HDL. We further show that HDL from Hp−/− mice on an atherogenic diet is anti-inflammatory and did not contain any Hb, suggesting that (i) Hp is required for the association of Hb with HDL, and (ii) Hp regulates the inflammatory properties of HDL. In contrast to HDL from Hp−/− mice, HDL from Hx−/− mice on normal chow was proinflammatory and associated with Hb and Hp, suggesting a novel protective role for Hx in HDL function. When apoE−/− mice were treated in vivo with an apoA-1 mimetic peptide, 4F, Hb·Hp·Hx dissociated from HDL. Our data strongly suggest that the association of Hb·Hp·Hx with HDL plays an important role in the functional status and inflammatory properties of HDL. 相似文献
97.
Tamalampudi S Talukder MM Hama S Tanino T Suzuki Y Kondo A Fukuda H 《Applied microbiology and biotechnology》2007,75(2):387-395
To expand the industrial applications of Candida antarctica lipase B (CALB), we developed Aspergillus oryzae whole-cell biocatalyst expressing the lipase-encoding gene from C. antarctica. A. oryzae niaD300, which was derived from the wild type strain RIB40, was used as the host strain. The CALB gene was isolated from
C. antarctica CBS6678 and expression plasmids were constructed with and without secretion signal peptide. The lipase gene was expressed
under the control of improved glaA and pNo-8142 promoters of plasmids pNGA142 and pNAN8142, respectively. The Southern blot
analysis demonstrated the successful integration of the CALB gene in the genome of A. oryzae. To determine the role of signal peptide, the expression plasmids were constructed with homologous and heterologous secretion
signal sequences of triacylglycerol lipase gene (tglA) from A. oryzae and lipase B (CALB) from C. antarctica, respectively. The C-terminal FLAG tag does not alter the catalytic properties of the lipase enzyme and Western blotting
analysis using anti-FLAG antibodies demonstrated the presence of cell wall and membrane bound lipase responsible for the biocatalytic
activity of the whole-cell biocatalyst. The resultant recombinant A. oryzae was immobilized within biomass support particles (BSPs) made of polyurethane foam (PUF) and the BSPs were successfully used
for the hydrolysis of para-nitrophenol butyrate (p-NPB) and for the optical resolution of (RS)-1-phenyl ethanol by enantioselective transesterification with vinyl acetate as acyl donor. 相似文献
98.
99.
Sang-Yong Kim Yoshiki Kashiwada Kazuyoshi Kawazoe Kotaro Murakami Han-Dong Sun Shun-Lin Li Yoshihisa Takaishi 《Phytochemistry letters》2009,2(3):110-113
Two new lindenane sesquiterpene dimers, spicachlorantins A and B (1 and 2), were isolated from the roots of Chloranthus spicatus along with a known related compound, chloramultilide A (3). Their structures and the absolute stereostructures were established by 1D and 2D NMR as well as by CD spectroscopic analyses. 相似文献
100.
Eyelid opening stretches mechanoreceptors in the supratarsal Müller muscle to activate the proprioceptive fiber supplied by the trigeminal mesencephalic nucleus. This proprioception induces reflex contractions of the slow-twitch fibers in the levator palpebrae superioris and frontalis muscles to sustain eyelid and eyebrow positions against gravity. The cell bodies of the trigeminal proprioceptive neurons in the mesencephalon potentially make gap-junctional connections with the locus coeruleus neurons. The locus coeruleus is implicated in arousal and autonomic function. Due to the relationship between arousal, ventromedial prefrontal cortex, and skin conductance, we assessed whether upgaze with trigeminal proprioceptive evocation activates sympathetically innervated sweat glands and the ventromedial prefrontal cortex. Specifically, we examined whether 60° upgaze induces palmar sweating and hemodynamic changes in the prefrontal cortex in 16 subjects. Sweating was monitored using a thumb-mounted perspiration meter, and prefrontal cortex activity was measured with 45-channel, functional near-infrared spectroscopy (fNIRS) and 2-channel NIRS at Fp1 and Fp2. In 16 subjects, palmar sweating was induced by upgaze and decreased in response to downgaze. Upgaze activated the ventromedial prefrontal cortex with an accumulation of integrated concentration changes in deoxyhemoglobin, oxyhemoglobin, and total hemoglobin levels in 12 subjects. Upgaze phasically and degree-dependently increased deoxyhemoglobin level at Fp1 and Fp2, whereas downgaze phasically decreased it in 16 subjects. Unilateral anesthetization of mechanoreceptors in the supratarsal Müller muscle used to significantly reduce trigeminal proprioceptive evocation ipsilaterally impaired the increased deoxyhemoglobin level by 60° upgaze at Fp1 or Fp2 in 6 subjects. We concluded that upgaze with strong trigeminal proprioceptive evocation was sufficient to phasically activate sympathetically innervated sweat glands and appeared to induce rapid oxygen consumption in the ventromedial prefrontal cortex and to rapidly produce deoxyhemoglobin to regulate physiological arousal. Thus, eyelid opening with trigeminal proprioceptive evocation may activate the ventromedial prefrontal cortex via the mesencephalic trigeminal nucleus and locus coeruleus. 相似文献