Nuclear DNA helicase II (NDH II) was first isolated from calf thymus using a DNA-unwinding assay. Subsequently it has been shown to be a homologue of human RNA helicase A (RHA) and the maleless protein (MLE) from Drosophila. Accordingly, the protein possesses both DNA and RNA unwinding activities. Also, it can use all four NTPs or dNTPs to fuel the reaction. At its N-terminus it possesses two double-strand RNA binding domains (dsRBD I and II), while the C-terminus comprises an imperfect glycine (G)- and arginine (R)-rich repeat, a so-called RGG-box that preferably binds to ssDNA or ssRNA. Many proteins interact with NDH II both at its N- and C-terminus and thereby mediate transcriptional regulation, RNA processing, and transport, the DNA damage response and genome surveillance. The latter includes the histone variant gamma-H2AX and the Werner syndrome helicase (WRN). Here we describe experimental approaches to obtain mechanistic information about this important nuclear helicase.

Variable pressure and temperature conductivity measurements on the bisthiaselenazolyl radical dimer [1a](2) have established the presence of a weakly metallic state over the pressure range 5-9 GPa. To explore the origin of this metallization we have examined the crystal and molecular structure of [1a](2) as a function of pressure. At ambient pressure the dimer consists of two radicals linked by a hypervalent 4-center 6-electron S...Se-Se...S sigma-bond into an essentially coplanar arrangement. The dimers are packed in cross-braced slipped pi-stack arrays running along the x-direction of the monoclinic (space group P2(1)/c) unit cell. Pressurization to 4 GPa induces little change in the molecular structure of [1a](2) or in the slipped pi-stack crystal architecture. Near 5 GPa, however, stress on the dimer leads to buckling of the two halves of the molecule and a contraction in the metrics of the S...Se-Se...S unit. These structural changes can be understood in terms of an electronic configurational switch from a 4-center 6-electron sigma-bonded dimer to a more conventional pi-bonded arrangement. At the same time the slipped pi-stack arrays undergo a concertina-like compression, and the crystal structure experiences highly anisotropic changes in cell dimensions. DFT calculations on the molecular electronic structure of the dimer indicate a marked decrease in the HOMO-LUMO gap as the dimer buckles. Related solid-state calculations indicate a rapid closure of the valence/conduction band gap in the same pressure region and the formation of a quasi-metallic state. Metallization of [1a](2) thus arises as much from intramolecular changes, which give rise to a collapse of the HOMO-LUMO gap and near coalescence of the valence and conduction bands, as from increased intermolecular interactions, which cause widening and overlap of the band edges.

OBJECTIVE: To investigate the effect of six cold traditional Chinese medicine on the energy metabolism factors in rats skeletal muscle. METHOD: The activity of Na(+)-K(+) -ATPase, Ca(2+) -ATPase and succinate dehydrogenase (SDH), the content of muscle glycogen, and the mRNA expression of skeletal muscle uncoupling protein 3 (UCP3) were measured after rats having been administrated with water extracts of Radix Sophorae Flavescentis, Fructus Gardeniae, Cortex Phellodendri, Radix Scutellariae, Rhizoma Coptidis, and Radix Gentianae respectively at the dose of 6.0, 7.0, 8.4, 6.0, 7.0, 4.0 g x kg(-1) for 30 days. RESULT: The activity of Na(+) -K(+) -ATPase has been depressed significantly and the content of skeletal muscle glycogen has been increased remarkably by six cold traditional Chinese medicine. The decreased tendency has been found on activity of Ca(2+) -ATPase and SDH, only the Radix scutellariaeg group decreased the Ca(2+) -ATPase activity significantly (P < 0.05), the SDH activity was decreased high significantly by Radix scutellariae, Cortex Phellodendri, Radix Gentianae and significantly by Rhizoma Coptidis. The mRNA expression of UCP3 has been decreased high significantly by all five cold traditional Chinese medicine except Cortex Phellodendri group with the decreased tendency of UCP3 mRNA expression. CONCLUSION: The cold traditional Chinese medicine has the significant effects on the skeletal muscle energy metabolism by decreasing the utlization of the glucose and the activity of mitochondria SDH to reduce the production of ATP, and depressing the activity of Na(+)-K(+) -ATPase and Ca(2+) -ATPase to cut down the consumption of ATP, by decreasing the mRNA expression of UCP3 to decrease the heat production.

AIMS/HYPOTHESIS: Treatment with the Cu(II)-selective chelator triethylenetetramine (TETA) improves cardiovascular disease in human patients, and cardiac and vascular/renal disease in rats used as a model of diabetes. Here we tested two hypotheses: first, that TETA elicits greater improvement in organ function than less Cu-selective transition-metal-targeted treatments; second, that the therapeutic actions of TETA are consistent with mediation through suppression of oxidative stress. METHODS: Rats were made diabetic with streptozotocin (55 mg/kg, i. v.) and treated from 8 weeks after disease induction for the following 8 weeks with effective dosages of oral TETA, or one of three less Cu-selective transition-metal-targeted treatments: D: -penicillamine, deferiprone or Zn acetate. Treatment effects were measured in ex vivo cardiac and aortic tissues, plasma and urine. RESULTS: Diabetes damaged both cardiac and renal/vascular function by impairing the ability of cardiac output to respond physiologically to rising afterload, and by significantly elevating the urinary albumin/creatinine ratio. Diabetes also lowered total antioxidant potential and heparan sulphate levels in cardiac and arterial tissues, and serum ferroxidase activity, whereas it elevated urinary heparan sulphate excretion. TETA treatment rectified or partially rectified all these defects, whereas the other three experimental treatments were ineffectual. By contrast, none of the four drug treatments lowered diabetes-mediated elevations of plasma glucose or lipid concentrations. CONCLUSIONS/INTERPRETATION: TETA may limit the cardiac and renal/vascular damage inflicted by diabetes through its actions to reinforce antioxidant defence mechanisms, probably acting through selective chelation of 'loosely-bound'/chelatable Cu(II). It may also improve heparan sulphate homeostasis and bolster antioxidant defence by increasing vascular extracellular superoxide dismutase activity. Urinary albumin/creatinine ratio might prove useful for monitoring TETA treatment.

Selenium (Se) is an essential trace mineral mediating its biological function primarily through selenoproteins. Accumulated lines of evidence indicate important roles of selenoproteins in the maintenance of optimal brain functions via redox regulation. Decreased expression of several selenoproteins is associated with the pathologies of a few age-associated neurodisorders, including Parkinson's disease, Alzheimer's disease and epilepsy. Recent advances using genetically manipulated mouse models demonstrate that selenoproteins offer protection against neurodegeneration primarily through redox regulation. Therapies targeting specific selenoproteins influencing redox regulation could delay the onset of neurodisorders, improve quality of life of patients already affected, and perhaps rescue patients with certain diseases by using novel gene therapies.

A chronocoulometric DNA sensor was constructed based on doped screen-printed electrode (SPE). Polyaniline nanotubes (PANINTs) and ionic liquid (IL) [C(12)mim][PF(6)] were doped into the commercial graphite ink (Electrodag 423SS) for the printing of the SPE, and chitosan was covered on the electrode surface. A homogeneous, stable and highly conductive electrode surface was thus obtained. A chronocoulometric DNA sensor was established based on this SPE. The target DNA sequences were specifically recognized by the capture probes immobilized on the SPE surface and the reporter probes labeled on reporter Au nanoparticles, which also carried bio-bar-code DNA sequences. The signals were generated through chronocoulometric interrogation of [Ru(NH(3))(6)](3+) ions that bound to the DNA strands (mainly bio-bar-code DNAs) via electrostatic interactions. The target DNA could be quantitatively detected in the range from 1.0x10(-16)M to 1.0x10(-14)M, and a detection limit of 8.0x10(-17)M was found. Selectivity against three-mismatched DNA was found in this sensor.

(Imido)vanadium(V) complexes containing the (2-anilidomethyl)pyridine ligand, V(NR)Cl(2)[2-ArNCH(2)(C(5)H(4)N)] (R = 1-adamantyl (Ad), cyclohexyl (Cy), phenyl), exhibit remarkably high catalytic activities (e.g. TOF = 2 730 000 h(-1) (758 s(-1)) by V(NAd)Cl(2)[2-(2,6-Me(2)C(6)H(3))NCH(2)(C(5)H(4)N)) for ethylene dimerization in the presence of MAO, affording 1-butene exclusively (selectivity 90.4 to >99%). The steric bulk of the imido ligand plays an important role in the selectivity (polymerization vs dimerization), and the electronic nature directly affects the catalytic activity (activity: R = Ad > Cy > Ph).

A chelation-assisted copper(II)-catalyzed ortho-acyloxylation of the 2-arylpyridine sp(2) C-H bond with anhydride is described. The procedure tolerates various functional groups, such as carbomethoxyl, methoxyl, fluoro, bromo, chloro, and cyano groups, affording the mono- or diacyloxylated products in moderate to good yields. Importantly, this procedure uses O(2) as a clean terminal oxidant.

The malic enzyme-encoding cDNA (GQ372891) from the oleaginous yeast Lipomyces starkeyi AS 2.1560 was isolated, which has an 1719-bp open reading frame flanked by a 290-bp 5' untranslated sequence and a 92-bp 3' untranslated sequence. The proposed gene, LsME1, encoded a protein with 572 amino acid residues. The protein presented 58% sequence identity with the malic enzymes from Yarrowia lipolytica CLIB122 and Aspergillus fumigatus Af293. The LsME1 gene was cloned into the vector pMAL-p4x to express a fusion protein (MBP-LsME1) in Escherichia coli TB1. The fusion protein was purified and then cleaved by Factor Xa to give the recombinant LsME1. This purified enzyme took either NAD(+) or NADP(+) as the coenzyme but preferred NAD(+). The K (m) values for malic acid, NAD(+) and NADP(+) were 0.85 +/- 0.05 mM, 0.34 +/- 0.08 mM, and 7.4 +/- 0.32 mM, respectively, at pH 7.3.

Pertussis continues to circulate in Chinese communities and older children, adolescents and adults are sources of infection for unprotected infants. Two studies conducted in Jiangsu Province in the People's Republic of China assessed the immunogenicity, reactogenicity and safety of Boostrix(), a combined reduced antigen content diphtheria-tetanus-acellular pertussis vaccine (dTpa) when administered as a booster dose to children 6 to 8 years of age. Immunogenicity was assessed before and one month after vaccination in a subset. Reactogenicity was assessed over a 4-day follow-up using diary cards. A total of 690 Chinese subjects were enrolled. Boostrix() was well tolerated. One month after the booster dose, 100% of dTpa recipients had seroprotective antibody concentrations against diphtheria and tetanus. The percentage of subjects with a response against pertussis antigens (using locally defined cut-offs) was 91.9% for pertussis toxoid, 98.8% for filamentous hemagglutinin, and 100% for pertactin. The exploratory analysis showed no statistically significant differences between dTpa or diphtheria-tetanus vaccine in terms of the percentage of subjects with seroprotective antibodies against diphtheria or tetanus. These studies demonstrate that Boostrix() is well tolerated and immunogenic when administered as a booster dose to 6 to 8 year old Chinese children previously immunized with a combined diphtheria-tetanus-pertussis vaccine. Introduction of dTpa into the routine Chinese immunization schedule would provide booster vaccination against pertussis without the addition of further injections into the Chinese vaccination schedule and is likely to promote improved pertussis control in older children.

In this paper, we report a biomolecule-assisted soft chemistry route for constructing complex Bi(2)S(3) nanostructures that exhibit controlled wetting behavior. The as-synthesized sample was characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), field emission SEM (FE-SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM), Fourier transform infrared (FT-IR), Raman, x-ray photoelectron (XPS) and photoluminescence (PL). The Raman spectra indicate that the surface optical (SO) phonon mode occurs in Bi(2)S(3) nanoparticles. The SO phonon mode is attributed to the defects on the surface of Bi(2)S(3) nanoparticles. In addition, the possible formation mechanism of the self-assembled urchin-like Bi(2)S(3) complex nanostructures is discussed. The established complex nanostructure can control the surface topology of a membrane to create a superhydrophobic surface. A water contact angle (CA) of > 150 degrees of the as-synthesized Bi(2)S(3) complex nanostructures can be obtained, which may find potential application in environmental chemistry.

Coherent control of two-photon fluorescence (TPF) of 2('),7(')-dichlorofluorescein in methanol solution was experimentally investigated by shaping the femtosecond pulse with the phase jump. The experimental results indicated that the TPF intensity induced by the shaped femtosecond pulses with certain phase jump could be coherently enhanced. The physical mechanisms for TPF enhancement in the molecular system were explicitly discussed and analyzed, which could be attributed to the wave-packet constructive interference in the excited states. Finally, two phase-locked femtosecond pulses were used to explore the wave-packet constructive interference in the excited states of 2('),7(')-dichlorofluorescein, which validate experimentally the proposed mechanism.

A theoretical study on fluorescence spectra of six coumarin dyes is given in the present paper. Their geometric configurations were optimized by semi-empirical method AM1. For all optimal configurations, there is no imaginary frequency in vibrational analysis. On this basis, the electronic spectra were calculated by CIS method. All the calculated results are basically consistent with experimental values.

OBJECTIVE: To analysis chemical components of volatile oil from the seed of Nigella glandulifera (NG), comparing them with those from the seed of foreign N. sativa (NS) and N. damascene (ND), and to quantify thymoquinone in the volatile oil extracted by hydrodistillation (HD) from the seed of NG. METHOD: The volatile oil was extracted by supercritical CO2 extraction (SFE-CO2 ) and HD from the seed of NG and its chemical components was analysed by GC-MS, the relative percentage of components were determined by peak aera normalization method and compare with those of the seed of NS and ND. The content of the thymoquinone in the volatile oil was determined by one point external standard method. RESULT: In terms of the volatile compounds, p-cymene is the major component of NG and NS, their relative percentage contents are 33.75% and 61.48%, respectively. beta-Elemene is the major component of ND, its relative percentage content is 73.24%. The relative percentage contents of thymoquinone are 3.73% (HD), 3.80% and 0.08% in NG, NS and ND, respectively. Linoleic acid is a major component of volatile oil by SFE-CO2 in NG, but its content of p-cymene is lower. The absolute percentage content of thymoquinone is 1.58% by HD in volatile oil of NG. CONCLUSION: There are comparatively large differences of volatile components in NG, NS and ND.

The ubiquity of fluoroquinolone antibiotics (FQs) in surface waters urges insights into their fate in the aqueous euphotic zone. In this study, eight FQs (ciprofloxacin, danofloxacin, levofloxacin, sarafloxacin, difloxacin, enrofloxacin, gatifloxacin, and balofloxacin) were exposed to simulated sunlight, and their photodegradation was observed to follow apparent first-order kinetics. Based on the determined photolytic quantum yields, solar photodegradation half-lives for the FQs in pure water and at 45 degrees N latitude were calculated to range from 1.25 min for enrofloxacin to 58.0 min for balofloxacin, suggesting that FQs would intrinsically photodegrade fast in sunlit surface waters. However, we found freshwater and seawater constituents inhibited their photodegradation. The inhibition was further explored by a central composite design using sarafloxacin and gatifloxacin as representatives. Humic acids (HA), Fe(III), NO(3)(-), and HA-Cl(-) interaction inhibited the photodegradation, as they mainly acted as radiation filters and/or scavengers for reactive oxygen species. The photodegradation product identification and ROS scavenging experiments indicated that the FQs underwent both direct photolysis and self-sensitized photo-oxidation via *OH and (1)O(2). Piperazinyl N(4)-dealkylation was primary for N(4)-alkylated FQs, whereas decarboxylation and defluorination were comparatively important for the other FQs. These results are of importance toward the goal of assessing the persistence of FQs in surface waters.

Gene transfer has been a critical step for gene therapy. Viral vectors and nonviral vectors are commonly used for gene transfer. It has been shown that nonviral vectors have the advantage over viral ones, as they are nonimmunogenic, easy to produce, and not oncogenic. However, they have the major limitation of inefficient transfection; the hybridized usage of nonviral vectors may provide a partial solution. This article reviews the hybrids (different materials used in one delivery system) of nonviral vectors for gene delivery including hybrids between cationic lipids and helper lipids, conjugates of peptides or targeting moieties and lipids, and hybrids of cationic liposomes and polymers.

Nuclear collisions recreate conditions in the universe microseconds after the Big Bang. Only a very small fraction of the emitted fragments are light nuclei, but these states are of fundamental interest. We report the observation of antihypertritons-comprised of an antiproton, antineutron, and antilambda hyperon-produced by colliding gold nuclei at high energy. Our analysis yields 70 +/- 17 antihypertritons ($${}_{\overline{\Lambda }};{3}\overline{\mathrm{H}}$$) and 157 +/- 30 hypertritons ($${}_{\Lambda };{3}\mathrm{H}$$). The measured yields of $${}_{\Lambda };{3}\mathrm{H}$$ ($${}_{\overline{\Lambda }};{3}\overline{\mathrm{H}}$$) and (3)He ((3)$$\overline{\mathrm{He}}$$) are similar, suggesting an equilibrium in coordinate and momentum space populations of up, down, and strange quarks and antiquarks, unlike the pattern observed at lower collision energies. The production and properties of antinuclei, and nuclei containing strange quarks, have implications spanning nuclear/particle physics, astrophysics, and cosmology.

In this paper, we report a kind of bioinspired high performance near-infrared improved transmittance silica surfaces with superhydrophobic properties by colloidal lithography, with transmittance about 99% from 1300 to 2000 nm. Meanwhile, the optical properties of such surfaces can be controlled by the antireflective structure morphologies resulting from the different reactive ion etching conditions. Using proper microspheres as mask, the high-performance near-infrared telecommunication optics can be achieved. Besides, the antireflective surfaces possess superhydrophobic properties after modified by fluorosilane. Such antireflective surfaces are promising for fabrication of highly light transmissive, antireflective, and superhydrophobic near-infrared optical materials to be used in many important fields.

This study aimed to examine the phenotypic, genetic and environmental correlations between percent fat mass (PFM) and bone parameters, especially hip geometry, among 786 males and 618 females aged 13-21 years from a Chinese twin cohort. PFM, bone area (BA), bone mineral content (BMC), cross-sectional area (CSA) and section modulus (SM) were obtained by dual-energy X-ray absorptiometry. Multiple linear regression models were used to assess the PFM-bone relationships. Structural equation model for twin design was used to estimate genetic/environmental influences on individual phenotype and phenotypic correlations. After controlling for body weight and other pertinent covariates, we observed inverse associations between PFM and bone parameters: compared to the lowest age- and gender-specific tertile of PFM, males in the highest tertile of PFM had lower measure of whole-body less head BA (WB-BA), lumbar-spine BA (L2L4-BA), total-hip BA (TH-BA), total-hip BMC, CSA and SM (all, p < 0.005, adjusted p < 0.05). Similar inverse associations were observed in females for all the above parameters except WB-BA and L2L4-BA. The above associations did not vary significantly by Tanner stages. In both genders, the estimated heritabilities were 80%-86% for BMC, 67%-80% for BA, 74%-77% for CSA and 64% for SM. Both shared genetics and environmental factors contributed to the inverse PFM-bone correlations. We concluded that in this sample of relatively lean Chinese adolescents, at a given body weight, PFM was inversely associated with BA, BMC and hip geometry in both genders, and such associations were attributed to both shared genetic and environmental factors. (c) 2010 American Society for Bone and Mineral Research.

Summary The objective of this methods paper is to examine a computational algorithm that may reveal how vessel length might depend on vessel diameter within any give stem or species. The computational method requires the assumption that vessels remain approximately constant in diameter over their entire length. When this method is applied to three species or hybrids in the genus Populus, vessel length is sometimes a linear function of vessel diameter and sometimes an exponential function of vessel diameter within a stem, based on R(2) values. Our results give within-species variation of vessel length versus diameter and we compare this to between-species variation of mean diameter versus mean length.