Mechanisms of Dipolar Ortho/Para-H2O Conversion in Ice

In this paper a possible explanation for an unexpected ortho/para-water ratio in the gas clouds of comets is given. The description is based on the quantum-mechanical density matrix formalism and the spin temperature concept. Only the nuclear spin system is treated quantum-mechanically. Employing the model of a four spin system, created by two nearest neighbour water molecules, spin eigenstates and their dynamics under the influence of their mutual dipolar interactions are studied. It is shown that a fast conversion between ortho- and para-states occurs on a msec time scale, caused by the intermolecular homonuclear magnetic dipolar interaction. Moreover the spin eigenstates of water in an ice crystal are determined by magnetic dipolar interactions and are not given by normal ortho- and para-H2O states of gaseous water. As a result of this the spin temperature of gaseous water evaporated from ice depends strongly on its evaporation history and the ortho/para-ratio of water molecules are only an indirect measure of the temperature of ice crystals from where they descend. This result could explain the unexpected experimentally observed ortho/para-ratios in the clouds of comets.

Genomic full length sequence of HLA-Cw*030301, identified by cloning and sequencing

Genomic full length sequence of human leukocyte antigen (HLA)-Cw*030301 that differs from Cw*030401 by two-nucleotide exchange at nt 473 (G>A) in exon 2 and nt 3033 (G>C) in 3'UTR, was identified by cloning and sequencing from a male Chinese donor.

SHARP-2 gene silencing by lentiviral-based short hairpin RNA interference prolonged rat kidney transplant recipients' survival time

Split- and hairy-related protein-2 (SHARP-2) controls the expression of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma), which both play a key role in transplant rejection. This study was designed to investigate whether SHARP-2 short hairpin RNA interference (shRNAi) could prolong the survival of rat kidney transplant recipients. A lentiviral-based shRNAi construct, LV-SHARP-2iC, showed a SHARP-2 gene silencing efficiency of 84% in normal rat kidney cells. In activated T-cells, SHARP-2 gene silencing with the LV-SHARP-2iC construct resulted in 61% and 69% down-regulation of IL-2 and IFN-gamma, respectively, compared with a scramble control construct. When donor kidney was perfused with 5 x 10(7) transforming units of the LV-SHARP-2iC construct, the median survival time of the transplant recipients was prolonged by 4 - 5 days compared with control groups. In conclusion, recombinant lentiviral LV-SHARP-2iC construct effectively silenced SHARP-2 gene expression, which reduced IL-2 and IFN-gamma mRNA expression and prolonged rat kidney transplant recipients' survival.

A novel HLA-Cw*04 allele, Cw*04010103, identified by genomic full length cloning and sequencing

A novel human leukocyte antigen-Cw*04 allele, Cw*04010103, was identified by genomic full length cloning and sequencing from a male Chinese donor. It differs from the closest related allele Cw*04010101 by one nucleotide exchange at nt 1111 (G>A) in intron 3.

K/pi Fluctuations at relativistic energies

We report K/pi fluctuations from Au + Au collisions at sqrt[s(NN)]= 19.6, 62.4, 130, and 200 GeV using the STAR detector at the Relativistic Heavy Ion Collider. K/pi fluctuations in central collisions show little dependence on incident energy and are on the same order as those from NA49 at the Super Proton Synchrotron in central Pb + Pb collisions at sqrt[s(NN)]=12.3 and 17.3 GeV. We report results for the collision centrality dependence of K/pi fluctuations and results for charge-separated fluctuations. We observe that the K/pi fluctuations scale with the charged particle multiplicity density.

A Comparison of Proximal Femoral Nail Antirotation and Dynamic Hip Screw Devices in Trochanteric Fractures

This prospective, randomized study compared the functional outcome and complications associated with a proximal femoral nail antirotation (PFNA) device with those of a traditional extramedullary device, the dynamic hip screw (DHS), in patients with trochanteric fracture. A total of 121 patients were randomized to the PFNA group ( n = 58) or the DHS group ( n = 63). Perioperative information and complications were recorded, and assessments of functional outcome were made. The DHS group required a longer operative time and was associated with greater blood loss than the PFNA group. The re-operation rate was lower in the PFNA group compared with the DHS group, especially in patients with unstable fractures, although there was no statistically significant difference in the overall complication rate between the two groups. There were no significant differences in functional outcome between the PFNA and the DHS groups. In conclusion, the PFNA device is useful in the treatment of trochanteric fractures.

Comparative responses in rare minnow exposed to 17beta-estradiol during different life stages

Present in the excrement of humans and animals, 17beta-estradiol (E(2)) has been detected in the aquatic environment in a range from several nanograms to several hundred nanograms per liter. In this study, the sensitivities of rare minnows during different life stages to E(2) at environmentally relevant (5, 25, and 100 ng l(-1)) and high (1000 ng l(-1)) concentrations were compared using vitellogenin (VTG) and gonad development as biomarkers under semistatic conditions. After 21 days of exposure, VTG concentrations in whole-body homogenates were analyzed; the results indicated that the lowest observed effective concentration for VTG induction was 25 ng l(-1) E(2) in the adult stage, but 100 ng l(-1) E(2) in the larval and juvenile stages. After exposure in the early life stage, the larval and juvenile fish were transferred to clean water until gonad maturation. No significant difference in VTG induction was found between the exposure and control groups in the adults. However, a markedly increased proportion of females and appearance of hermaphrodism were observed in the juvenile-stage group exposed to 25 ng l(-1) E(2). These results showed that VTG induction in the adult stage is more sensitive than in larval and juvenile stages following exposure to E(2). The juvenile stage may be the critical period of gonad development. Sex ratio could be a sensitive biomarker indicating exposure to xenoestrogens in early-life-stage subchronic exposure tests. The results of this study provide useful information for selecting sensitive biomarkers properly in aquatic toxicology testing.

Profile of volatile compounds in 11 brandies by headspace solid-phase microextraction followed by gas chromatography-mass spectrometry

A headspace solid-phase microextraction (HS-SPME) method coupled with gas chromatography-mass spectrometry (GC-MS) was applied for the qualitative or semiquantitative characterization of brandy volatiles. SPME variables (SPME fiber, extraction temperature and time, and ethanol concentration) were optimized. A total of 144 compounds were from the brandies' volatiles, tentatively identified or identified by comparing mass spectra and retention indices of the standards or from literature. Of these, 57 are common to 11 brandies. They were mainly represented by esters and alcohols, such as 2-methyl propanol, 3-methyl butanol, 1-hexanol, ethyl octanoate, and ethyl decanoate, which were quantitatively determined. Chromatographic peaks were integrated using selective ion method (SIM) and the semiquantitative data analyzed using principal component analysis (PCA) and cluster analysis (CA) to study relationships between volatile composition and brandy. Eleven brandies were differentiated into 3 groups: 1 for Hennessy VSOP and XO samples, 1 for Changyu PEGASE VSOP and XO-1, 2, 3 samples, and the other for Changyu PEGASE brandy and VO, Taro brandy, Baiyang River brandy, and Wealth XO samples. The classification of groups is consistent with the brandy samples by variety and grade.

Genetic polymorphism of catechol O-methyltransferase and pharmacokinetics of levodopa in healthy Chinese subjects

We studied the distribution of catechol O-methyltransferase (COMT) genotypes in the Chinese Fujian Han population and explored the potential effect of COMT genetic polymorphism on the pharmacokinetics of levodopa. Polymerase chain reaction (PCR) was employed in the COMT genotype analysis of 166 volunteers. After a single oral dose of levodopa/benserazide, the plasma concentration of levodopa was determined by high-performance liquid chromatography (HPLC) with electrochemical detection (ECD). In the 166 subjects, the frequencies of G/G, G/A and A/A COMT genotypes were 58.4%, 36.7% and 4.9%, respectively. The frequency of the homozygous A/A genotype was much lower than in caucasians and Southwest Asians. COMT activity of erythrocytes in the G/A genotype group was significantly lower than in the G/G genotype group but significantly higher than in the A/A genotype group. There was no significant difference in pharmacokinetic parameters, including t(1/2alpha), t(1/2beta), AUC(0-infinity), CL/F, C(max), t(max) and V/F. The frequency of COMT genotypes in the Chinese Fujian Han population, which is related to COMT enzyme activity, is significantly different from that in caucasians and Southwest Asians. The pharmacokinetic characteristics of levodopa in healthy Chinese subjects may not be dependent on their COMT genotype status. From the 166 volunteers, 5 G/G, 5 G/A and 4 A/A genotype male subjects were recruited for the study of levodopa pharmacokinetics.

The effect of Malononitrilamides (FK778) on phenotypic properties of human peripheral dendritic cells

BACKGROUND

FK778, a malononitrilamide analogue of lefunomide, is currently a promising immunosuppressive drug. Because the cellular and molecular mechanisms underlying the effects of FK778 are not entirely clarified. We studied its effects on human peripheral dendritic cells.

METHODS

Peripheral blood mononuclear cells (PBMC) from 12 healthy volunteers were isolated by density separation over Ficoll solution. After resuspension in adaptive immunotherapy medium (AIM)-V medium, they were cultured without exogenous growth factors. The study group was treated with FK 778 (50 microg/mL) or Rapamycin (10 ng/mL). The phenotype of dendritic cell was ascertained by indirect immunoflurescence for analysis by flow cytometry.

RESULTS

Compared with the Rapamycin-treated controls, the expressions of CD80, CD83, CD86, HLA-DA, CD54, CD62, CCR5, and CCR7 in the FK778-treated myeloid dendritic cells and the expression of CD80, CD83, CD86, HLA-DA, and CD54 in the FK778-treated plasmacytoid dendritic cells were significantly down-regulated.

CONCLUSION

FK778 inhibited the differentiation and maturation of dendritic cells.

Selective precipitation of Cu from Zn in a pS controlled continuously stirred tank reactor

Copper was continuously and selectively precipitated with Na(2)S to concentrations below 0.3 ppb from water containing around 600 ppm of both Cu and Zn in a Continuously Stirred Tank Reactor. The pH was controlled at 3 and the pS at 25 (pS=-log(S(2-))) by means of an Ag(2)S sulfide selective electrode. Copper's recovery and purity were about 100%, whereas the total soluble sulfide concentration was below 0.02 ppm. X-ray diffraction (XRD) analysis showed that copper precipitated as hexagonal CuS (covellite). The mode of the particle size distribution (PSD) of the CuS precipitates was around 36 microm. The PSD increased by high pS values and by the presence of Zn. Depending on the turbulence, the CuS precipitates can grow up to 200 microm or fragment in particles smaller than 3 microm in a few seconds. Zn precipitation with Na(2)S at pH 3 and 4, in batch, always lead to Zn concentrations above 1 ppm. Zn precipitated as cubic ZnS (spharelite).