Impairment of spatial memory accuracy improved by Cbr1 copy number resumption and GABA receptor-dependent enhancement of synaptic inhibition in Down syndrome model mice.

Down syndrome is a complex genetic disorder caused by the presence of three copies of the chromosome 21 in humans. The most common models, carrying extra-copies of overlapping fragments of mouse chromosome 16 that is syntenic to human chromosome 21, are Ts2Cje, Ts1Cje and Ts1Rhr mice. In electrophysiological analyses using hippocampal slices, we found that the later phase of the depolarization during tetanic stimulation, which was regulated by GABA receptors, was significantly smaller in Ts1Cje and Ts2Cje mice than that in WT controls but not in Ts1Rhr mice.

Measurement of the α1-proteinase inhibitor (α1-antitrypsin) of common marmoset and intestinal protein loss in wasting syndrome.

Although wasting marmoset syndrome (WMS) is one of the biggest problems facing captive marmoset colonies, the mechanisms underlying its pathogenesis remain unclear. In our clinical experience, it is difficult to cure WMS-affected marmosets with severe hypoalbuminemia. Thus, the mechanisms underlying hypoalbuminemia in WMS must be understood.

Ts1Cje Down syndrome model mice exhibit environmental stimuli-triggered locomotor hyperactivity and sociability concurrent with increased flux through central dopamine and serotonin metabolism.

Ts1Cje mice have a segmental trisomy of chromosome 16 that is orthologous to human chromosome 21 and display Down syndrome-like cognitive impairments. Despite the occurrence of affective and emotional impairments in patients with Down syndrome, these parameters are poorly documented in Down syndrome mouse models, including Ts1Cje mice. Here, we conducted comprehensive behavioral analyses, including anxiety-, sociability-, and depression-related tasks, and biochemical analyses of monoamines and their metabolites in Ts1Cje mice.

Search for plasma biomarkers in drug-free patients with bipolar disorder and schizophrenia using metabolome analysis.

Aim: There is an urgent need for diagnostic biomarkers of bipolar disorder (BD) and schizophrenia (SZ); however, confounding effects of medication hamper biomarker discovery. In this study, we conducted metabolome analyses to identify novel plasma biomarkers in drug-free patients with BD and SZ.

Methods: We comprehensively analyzed plasma metabolites using capillary electrophoresis time-of-flight mass spectrometry in patients with SZ (n = 17), BD (n = 6), and major depressive disorder (n = 9) who had not received psychotropics for at least 2 weeks, and in matched healthy controls (n = 19).

ERp44 Exerts Redox-Dependent Control of Blood Pressure at the ER.

Blood pressure maintenance is vital for systemic homeostasis, and angiotensin II is a critical regulator. The upstream mechanisms that regulate angiotensin II are not completely understood. Here, we show that angiotensin II is regulated by ERp44, a factor involved in disulfide bond formation in the ER.

Photochemistry of fac-[Re(bpy)(CO)3Cl].

The photochemistry of fac-[Re(bpy)(CO)(3)Cl] (1 a; bpy=2,2'-bipyridine) initiated by irradiation using <330 nm light has been investigated. Isomerization proceeded in THF to give the corresponding mer-isomer 1 b. However, in the presence of a small amount of MeCN, the main product was the CO-ligand-substituted complex (OC-6-24)-[Re(bpy)(CO)(2) Cl(MeCN)] (2 c; bpy=2,2'-bipyridine).

Effects of the disappearance of one charge on ultrafast fluorescence dynamics of the FMN binding protein.

Crystal structures of E13T (Glu13 was replaced by Thr13) and E13Q (Glu13 was replaced by Gln13) FMN binding proteins (FMN-bp) from Desulfovibrio vulgaris, strain Miyazaki F, were determined by the X-ray diffraction method. Geometrical factors related to photoinduced electron transfer from Trp32, Tyr35, and Trp106 to the excited isoalloxazine (Iso*) were compared among the three forms of FMN-bp. The rate of ET is considered to be fastest from Trp32 to Iso* in FMN-bp and then from Tyr35 and Trp106.

Ultrafast solvation dynamics of flavin mononucleotide in the reductase component of p-hydroxyphenylacetate hydroxylase.

The reductase unit of p-hydroxyphenylacetate hydroxylase contains flavin mononucleotide (FMN) as a cofactor. Fluorescence decay curves measured by fluorescence up-conversion method were remarkably dependent on monitored emission wavelength. The fluorescence lifetime was shorter at the shorter emission wavelengths and longer at the longer wavelengths.

Ultrafast photodissociation dynamics of a hexaarylbiimidazole derivative with pyrenyl groups: dispersive reaction from femtosecond to 10 ns time regions.

The photodissociation dynamics of a hexaarylbiimidazole (HABI) derivative with two pyrenyl groups was investigated by time-resolved transient absorption spectroscopy and fluorescence measurements. Transient absorption spectroscopy revealed that photodissociation took place in the wide time region of <100 fs to 10 ns. On the other hand, fluorescence time profiles showed the dynamic red shift in the time region <100 ps.

Quantum mechanical study of photoinduced charge transfer in FMN binding protein.

CT interactions between Iso* and nearby aromatic amino acids in FBP were investigated by a semiempirical MO method. Atomic coordinates of lumiflavin as Iso, 3-methylindole as Trp, and 4-methylphenol as Tyr, used for MO calculations, were obtained from crystal, 20 NMR structures and 40 MD structures (20 ps time intervals). Geometries of Iso-Trp32, Iso-Trp106 and Iso-Tyr35 systems were optimized by the PM3 method.

Simultaneous analysis of ultrafast fluorescence decays of FMN binding protein and its mutated proteins by molecular dynamic simulation and electron transfer theory.

Ultrafast fluorescence decays of FMN binding proteins (FBP) from Desulfovibrio vulgaris (Miyazaki F) were analyzed with an electron transfer (ET) theory by Kakitani and Mataga (KM theory). Time-dependent distances among isoalloxazine (Iso) and Trp-32, Tyr-35, and Trp-106 in wild-type FBP (WT), among Iso and Tyr-32, Tyr-35, and Trp-106 in W32Y (Trp-32 was replaced by Tyr-32), and among Iso and Tyr-35 and Trp-106 in W32A (Trp-32 was replaced by Ala-32) were determined by molecular dynamic simulation (MD). Electrostatic energies between Iso anion and all other ionic groups, between Trp-32 cation and all other ionic groups, and between Tyr-32 cation and all other ionic groups were calculated in WT, W32Y, and W32A, from the MD coordinates.

Comparison between ultrafast fluorescence dynamics of FMN binding protein from Desulfovibrio vulgaris, strain Miyazaki, in solution vs crystal phases.

Ultrafast fluorescence dynamics of FMN binding protein (FBP) from Desulfobivrio vulgaris, strain Miyaxaki F, were compared in solution and crystal phases. Fluorescence lifetimes of FBP were 167 fs (96%) and 1.5 ps (4%) in solution (tau(av) = 220 fs), and 730 fs (60%) and longer than 10 ps (40%) in crystals (tau(av) = 4.

Donor-acceptor distance-dependence of photoinduced electron-transfer rate in flavoproteins.

Ultrafast fluorescence quenching of flavin in flavodoxin from Megasphaera elsdenii was investigated by means of a fluorescence up-conversion method. Fluorescence lifetimes of flavodoxin from M. elsdenii were estimated to be tau(1) approximately 165 fs (0.

Energy and electron transfer in the photosynthetic reaction center complex of Acidiphilium rubrum containing Zn-bacteriochlorophyll a studied by femtosecond up-conversion spectroscopy.

A photosynthetic reaction center (RC) complex was isolated from a purple bacterium, Acidiphilium rubrum. The RC contains bacteriochlorophyll a containing Zn as a central metal (Zn-BChl a) and bacteriopheophytin a (BPhe a) but no Mg-BChl a. The absorption peaks of the Zn-BChl a dimer (P(Zn)), the accessory Zn-BChl a (B(Zn)), and BPhe a (H) at 4 K in the RC showed peaks at 875, 792, and 753 nm, respectively.

Brain-derived neurotrophic factor enhances expression of superior cervical ganglia clone 10 in lateral geniculate nucleus and visual cortex of developing kittens.

Neuronal growth-associated proteins, including superior cervical ganglia clone 10 (SCG10) family molecules, play roles in neurite outgrowth and network formation as well as structural and functional plasticity. The present ontogenetic study revealed that the expression of neuronal growth-associated proteins in the visual cortex (VC) exhibited a sharp peak in the early postnatal period when growing lateral geniculate nucleus (LGN) axon terminals segregate into the ocular dominance columns depending on retinal activity. We then hypothesized that SCG10 family molecules, known for catastrophic factors of microtubules, play important roles in the formation of ocular dominance columns.

Experience-dependent pruning of dendritic spines in visual cortex by tissue plasminogen activator.

Sensory experience physically rewires the brain in early postnatal life through unknown processes. Here, we identify a robust anatomical consequence of monocular deprivation (MD) in layer II/III of visual cortex that corresponds to the rapid, functional loss of responsiveness preceding any changes in axonal input. Protrusions on pyramidal cell apical dendrites increased steadily after eye opening, but were transiently lost through competitive mechanisms after brief MD only during the physiological critical period.

Ultrafast charge separation and radiationless relaxation processes from higher excited electronic states of directly linked porphyrin-acceptor dyads.

We have investigated photoinduced electron transfer (ET) and related processes from the higher excited electronic state (S2) of Zn-porphyrin-imide acceptor directly linked supramolecular systems (ZP-I) designed especially for the critical studies of the energy gap law (EGL) of the charge separation (CS) from the S2 state, effects of solvent dynamics and intramolecular vibrations on this CS, and competition or cooperation between this CS and S2-->S1 conversion, etc. In this study, we have confirmed the modification of the EGL for the CS from S2 induced by the change of solvent polarity by comparing the EGL in toluene solution with that in THF, i.e.

Permissive proteolytic activity for visual cortical plasticity.

The serine protease, tissue-type plasminogen activator (tPA) is a key regulator of extracellular proteolytic cascades. We demonstrate a requirement for tPA signaling in the experience-dependent plasticity of mouse visual cortex during the developmental critical period. Proteolytic activity by tPA in the binocular zone was typically increased within 2 days of monocular deprivation (MD).

Experience-dependent plasticity of mouse visual cortex in the absence of the neuronal activity-dependent marker egr1/zif268.

Neuronal activity elicits a rapid increase in the expression of several immediate early genes (IEGs). To clarify a role for IEG response in activity-dependent development, we examined the contribution of the egr1/zif268 gene during visual cortical processing and plasticity in mice. We first analyzed the expression of egr1 mRNA in wild-type (WT) mice using Northern blot hybridization.

Energy-gap dependence of photoinduced charge separation and subsequent charge recombination in 1,4-phenylene-bridged zinc--free-base hybrid porphyrins.

A series of 1,4-phenylene-bridged ZP-HP hybrid porphyrins (ZP = zinc porphyrin, HP = free-base porphyrin) 1-8 ZH have been prepared in which an electron-donating ZP moiety is kept constant and electron-accepting HP moieties are varied by introducing electron-accepting substituents, so that the energy gap for charge separation, ZP-1HP*--> ZP(+)-HP-, covers a range of about 0.9 eV in DMF. Here selective excitation at the HP moiety was employed to avoid complication in the determination of electron transfer rates derived from energy transfer, 1ZP*-HP --> ZP-1HP*.

Effects of monocular enucleation on parvalbumin in rat visual system during postnatal development.

Purpose: To evaluate the hypothesis that the expression of the calcium-binding protein parvalbumin (PV) in a subpopulation of gamma-aminobutyric acid (GABA)ergic neurons is an appropriate molecular marker for the effect on ocular dominance plasticity of monocular deprivation during the postnatal sensitive period.

Methods: Long-Evans rats underwent monocular enucleation immediately before eye opening (postnatal day [P] 14). Immunohistochemical analysis using anti-PV antibody was performed on the superior colliculus (SC) and lateral geniculate nucleus (LGN) at P45.

Articular cartilage cells immortalized by a temperature sensitive mutant of SV40 large T antigen survive and form cartilage tissue in articular cartilage environment.

A chondrogenic cell line, TC6, was established by using cells derived from articular cartilage of transgenic mice harboring a temperature-sensitive mutant simian virus (SV) 40 large T-antigen gene. TC6 cells express genes encoding proteins related to cartilage phenotypes such as type II collagen. To examine the in vivo behavior of the TC6 cells, these cells were implanted into cavity-shaped full-thickness defects made in the articular cartilage of the central part of the patellar grooves of mouse femora.