Preparation and characterization of rare earth modified nanocrystalline Al2O3/13 wt%TiO2 feedstock for plasma spraying

The preparation and characterization of RE modified nanocrystalline Al2O3/13 wt%TiO2 feedstock for plasma spraying are described in this paper. Taking individual nano particles as starting materials, by wet ball milling, spray drying, sintering and plasma treating, nanocrystalline plasma sprayable feedstock is prepared. The as-prepared feedstocks were analyzed by XRD, SEM, EDS, TEM and HRTEM methods. As shown from analyses results, the reconstituted agglomerate feedstock possesses spherical geometry, proper particle size, homogeneous composition distribution and nano scaled grains. There are three dimensional net structures in the prepared feedstock, which could be retained in coatings if the feedstock does not melt or partially melts during the plasma spray process. The three dimensional net structures could play an important role in improving crack propagation resistance and wear resistance of coatings. The reconstitution process and characterization methods discussed in this paper can also be applied to prepare intraclass nanocrystalline feedstock such as ZrO2/Y2O3 and Cr2O3 et al.

Charge order in LuFe2O4: antiferroelectric ground state and coupling to magnetism

X-ray scattering by multiferroic LuFe2O4 is reported. Below 320 K, superstructure reflections indicate an incommensurate charge order with propagation close to (1/3 1/3 3/2). The corresponding charge configuration, also found by electronic structure calculations as most stable, contains polar Fe/O double layers with antiferroelectric stacking. Diffuse scattering at 360 K, with (1/3 1/3 0) propagation, indicates ferroelectric short-range correlations between neighboring double layers. The temperature dependence of the incommensuration indicates that charge order and magnetism are coupled.

Imaging findings of extraventricular neurocytoma: report of 3 cases and review of the literature

Extraventricular neurocytoma (EVN) is rare entity with similar biologic behavior and histopathologic characteristics to neurocytomas that occur in the lateral ventricles, according to the 2007 World Health Organization classification. We report the cases of 3 patients with extraventricular neurocytoma, which presented as large tumors in the left frontal and parietal lobes and in the sellar region. MR imaging showed cystic degeneration, calcification and/or hemorrhage, intense enhancement, and perilesional edema. EVN should be considered in the differential diagnosis for large, heterogeneous, enhancing brain tumors that occur in young people.

Three-dimensional magnetic correlations in multiferroic LuFe2O4

We present single crystal neutron diffraction measurements on multiferroic LuFe(2)O(4). Magnetic reflections are observed below transitions at 240 and 175 K indicating that the magnetic interactions in LuFe(2)O(4) are three-dimensional in character. The magnetic structure is refined as a ferrimagnetic spin configuration below the 240 K transition. Below 175 K a significant broadening of the magnetic peaks is observed along with the buildup of a diffuse component to the magnetic scattering.

Quantum spin correlations in an organometallic alternating-sign chain

High resolution neutron scattering is used to study excitations in the organometallic magnet (CH3)2NH2CuCl3 (DMACuCl3). Combined with bulk magnetization and susceptibility studies, the new results imply that DMACuCl3 is a realization of the S=1/2 alternating antiferromagnetic-ferromagnetic (AFM-FM) chain. Coupled-cluster calculations indicate that the AFM and FM interactions have nearly the same strength, while analysis of scattering intensities shows evidence for interdimer spin correlations. Results are discussed in the context of recent ideas concerning quantum entanglement.

Changes of cytosol glucocorticoid receptor and renal Na(+)-K(+)-ATPase activity after swimming training in rat

AIM

The aim of this study was to determine whether the down-regulation of glucocorticoid receptor (GR) by physical changes in plasma glucocorticoid hormones (GCs) is accompanied by changes in the responsiveness of target cells to GCs in rats.

METHODS

Normal male Sprague-Dawley rats were left to swim for 60 min. At 15 min and at 3, 12, 24 h after swimming training, groups of rats were sacrificed.

RESULTS

The results show that exposure of rats to a 60-min swimming stress provokes corticosterone secretion, which results in a rapid depletion of GR from renal cytosol and the subsequent induction of the renal Na(+)-K(+)-ATPase. By employing RU38486 and Trilostane before swimming training, both the effects of GCs on regulating GR binding activity and related changes in GR binding capacity to Na(+)-K(+)-ATPase activity are also investigated. RU38486 was shown to reduce GR by about 80% and the inducing effort of GCs on Na(+)-K(+)-ATPase was prevented by pretreatment of RU38486 and Trilostane.

CONCLUSION

These data suggest that physiological fluctuations in endogenous hormone secretion are sufficient to result not only in substantial cytosol GR down-regulation, but in a coordinate physiological response.

Odontogenic tumours: a retrospective study of 1642 cases in a Chinese population

A total of 1642 odontogenic tumour cases retrieved from the files of the College of Stomatology, Sichuan University, China were retrospectively analyzed for gender, age, tumour site and relative frequency of various types, and the data compared with that of previous reports. The final diagnosis in each case was based on the WHO 2005 histopathological classification of odontogenic tumours. Of these tumours 1592 (97.0%) were benign and 50 (3.0%) were malignant. Ameloblastoma (40.3%) was the most frequent type, followed by keratocystic odontogenic tumour (35.8%), odontoma (4.7%) and odontogenic myxoma (4.6%). The mean age of the patients was 32.1, with a wide range (3-84 years). The male-female ratio and maxilla-mandible ratio were 1.4:1 and 1:4.0, respectively. Ameloblastoma and keratocystic odontogenic tumours, important indications of extensive surgical procedures, are not considered rare in this Chinese population, whereas odontoma is uncommon.

Origin of the Mesozoic magmatism in the North China Craton: constraints from petrological and geochemical data

Voluminous plutonic and volcanic rocks were emplaced in the eastern part of the North China Craton (NCC) in the Mesozoic. The Mesozoic igneous rocks include a variety of rock types ranging from monzogabbroic, through monzonitic to monzogranitic, and locally to syenitic. Monzonitic rocks are dominant, and frequently contain mafic enclaves (dioritic in composition). The principal geochemical signatures of these Mesozoic rocks include high-K calc-alkaline to shoshonitic affinity, high Sr–Ba abundances and high Sr/Y, La/Yb, and highly enriched Sr–Nd isotopic compositions with εNd(t) ranging from −8 to −20 and ISr from 0.7053 to 0.710. Zircon sensitive high-resolution ion microprobe dating reveals that these Mesozoic rocks formed between 180 Ma and 120 Ma, but are predominantly confined to a narrow range of 135–127 Ma. The sudden surge of Mesozoic magmatism was genetically linked to the upwelling of asthenosphere in a back-arc extensional regime that was caused by subduction of the palaeo-pacific plate beneath the eastern NCC. Upwelling of hot asthenospheric mantle material triggered partial melting of enriched subcontinental lithosperic mantle, generating voluminous mafic magmas. The mafic magmas underplated in the lower crust and sparked melting of the latter, producting granitic melts. We suggest that the Mesozoic rocks in the NCC probably originated from mixing between the coeval mafic and granitic melts, followed by fractionation of ferromagnesian phases and subordinate plagioclase, rather than from melting of mafic lower crust as previously suggested by many others.

Novel IRF6 mutations in Chinese patients with Van der Woude syndrome

Van der Woude syndrome (VWS) (OMIM 119300) is a dominantly inherited, developmental disorder that is characterized by pits and/or sinuses of the lower lip and a cleft lip and/or cleft palate. Mutations in the interferon regulatory factor 6 gene (IRF6) have been recently identified in patients with VWS, with more than 60 mutations reported. However, the VWS phenotype, IRF6 mutation genotypes, and their interrelationships in Chinese VWS patients have not been studied. Here, we report 11 Chinese families with variable clinical phenotypes of VWS and identified mutations in all patients. Of the 11 mutations, 8 appeared to be novel: CC5.6GT, T342A, 566delA, C748T, C756A, C989A, C1209G, and 1316delT. Seven mutations caused a change or loss of the IRF6 domain. The marked phenotypic variation may be caused by the action of certain modifier genes on IRF6 function.

Probing Nanoscale Ferroelectricity by Ultraviolet Raman Spectroscopy

We demonstrated that ultraviolet Raman spectroscopy is an effective technique to measure the transition temperature (Tc) in ferroelectric ultrathin films and superlattices. We showed that one-unit-cell-thick BaTiO3 layers in BaTiO3/SrTiO3 superlattices are not only ferroelectric (with Tc as high as 250 kelvin) but also polarize the quantum paraelectric SrTiO3 layers adjacent to them. Tc was tuned by approximately 500 kelvin by varying the thicknesses of the BaTiO3 and SrTiO3 layers, revealing the essential roles of electrical and mechanical boundary conditions for nanoscale ferroelectricity.

Serological identification and bioinformatics analysis of immunogenic antigens in multiple myeloma

Identifying appropriate tumor antigens is critical to the development of successful specific cancer immunotherapy. Serological analysis of tumor antigens by a recombinant cDNA expression library (SEREX) allows the systematic cloning of tumor antigens recognized by the spontaneous autoantibody repertoire of cancer patients. We applied SEREX to the cDNA expression library of cell line HMy2, which led to the isolation of six known characterized genes and 12 novel genes. Known genes, including ring finger protein 167, KLF10, TPT1, p02 protein, cDNA FLJ46859 fis, and DNMT1, were related to the development of different tumors. Bioinformatics was performed to predict 12 novel MMSA (multiple myeloma special antigen) genes. The prediction of tumor antigens provides potential targets for the immunotherapy of patients with multiple myeloma (MM) and help in the understanding of carcinogenesis. Crude lysate ELISA methodology indicated that the optical density value of MMSA-3 and MMSA-7 were significantly higher in MM patients than in healthy donors. Furthermore, SYBR Green real-time PCR showed that MMSA-1 presented with a high number of copy messages in MM. In summary, the antigens identified in this study may be potential candidates for diagnosis and targets for immunotherapy in MM.

MICA-STR, HLA-B haplotypic diversity and linkage disequilibrium in the Hunan Han population of southern China

Major histocompatibility complex (MHC) class I chain-related gene A (MICA) is located 46 kb centromeric to HLA-B and encodes a stress-inducible protein. MICA allelic variation is thought to be associated with disease susceptibility and immune response to transplants. This study was aimed to investigate the haplotypic diversity and linkage disequilibrium between human leukocyte antigen (HLA)-B and (GCT)(n) short tandem repeat in exon 5 of MICA gene (MICA-STR) in a southern Chinese Han population. Fifty-eight randomly selected nuclear families with 183 members including 85 unrelated parental samples were collected in Hunan province, southern China. HLA-B generic typing was performed by polymerase chain reaction-sequence-specific priming (PCR-SSP), and samples showing novel HLA-B-MICA-STR linkage were further typed for HLA-B allelic variation by high-resolution PCR-SSP. MICA-STR allelic variation and MICA gene deletion (MICA*Del) were detected by fluorescent PCR-size sequencing and PCR-SSP. Haplotype was determined through family segregation analysis. Statistical analysis was applied to the data of the 85 unrelated parental samples. Nineteen HLA-B specificities and seven MICA-STR allelic variants were observed in 85 unrelated parental samples, the most predominant of which were HLA-B*46, -B60, -B*13, and -B*15, and MICA*A5, MICA*A5.1 and MICA*A4, respectively. Genotype distributions of HLA-B, MICA-STR loci were consistent with Hardy-Weinberg proportions. The HLA-B-MICA-STR haplotypic phases of all 85 unrelated parental samples were unambiguously assigned, which contained 30 kinds of HLA-B, MICA-STR haplotypic combinations, nine of them have not been reported in the literature. Significant positive linkage disequilibria between certain HLA-B and MICA-STR alleles, including HLA-B*13 and MICA*A4, HLA-B*38 and MICA*A9, HLA-B*58 and MICA*A9, HLA-B*46 and MICA*A5, HLA-B*51 and MICA*A6, HLA-B*52 and MICA*A6, and HLA-B60 and MICA*A5.1, were observed. HLA-B*48 was linked to MICA*A5, MICA*A5.1 and MICA*Del. HLA-B*5801-MICA*A10 linkage was found in a family. Our data indicated a high degree of haplotypic diversity and strong linkage disequilibrium between MICA-STR and HLA-B in a southern Chinese Han population, the data will inform future studies on anthropology, donor-recipient HLA matching in clinical transplantation and HLA-linked disease association.

Oxaliplatin/CF/5-FU versus paclitaxel/CF/5-FU in patients with advanced gastric cancer: A phase II clinical trial

14014

Background: Although many randomized trials of chemotherapy for advanced gastric cancer have been reported during the past two decades, no standard regimens worldwide have been established yet. Now Paclitaxel and Oxaliplatin have shown promising activity in advanced gastric cancer. We prospectively evaluated toxicity, efficacy and survival of Oxaliplatin /CF/5-FU versus Paclitaxel/CF/5-FU. Methods: Metastatic or locally advanced gastric cancer; performance status (PS) 0–2. Patients (pts) were enrolled and randomized into arm A with Oxaliplatin 100mg/m2, 5-FU 400 mg/m2 bolus, FA 200 mg/m2 2h, 5-FU 2500 mg/m2 46h, q2w or into arm B with Paclitaxel 80 mg/m2, 5-FU 400 mg/m2 bolus, FA 200 mg/m2 2h, 5-FU 2500 mg/m2 46h, q2w. Results: From 2000 to 2005, (A/B) 46/43 pts were enrolled into this study. Median age (52/50 y), gender, PS, localization and numbers of metastatic sites were comparable for both arms. Pts who were not chemotherapy naive in A/B (% of pts) were 41.3/33.3. All pts were eligible and evaluable for toxicity and response. Overall response (CR+PR) rate for A/B (% of pts): 37.0/47.2 (p<0.05), tumor control rate (CR+PR+SD) 76.1/69.4(p<0.05). Median time to progression (TTP) were for A/B: 6.0 and 3.2 months. And median survival time for A/B were 13.4 and 13.8 months. Grade 3/4 toxicities were for A/B (% of pts): neutropenia 10.9/5.6, thrombocytopenia 4.3/2.8, anemia 0/2.8, vomiting 8.7/2.8, neurotoxic 0/2. No treatment-related death occurred in A/B. Conclusions: Oxaliplatin /CF/5-FU and Paclitaxel/CF/5-FU are both effective and safe in advanced or metastatic gastric cancer. Though Oxaliplatin /CF/5-FU had better tumor control rate and median TTP, there was no difference between the arms in the median survival time.

No significant financial relationships to disclose.

Effect of dendritic cell vaccine against a tongue squamous cell cancer cell line (Tca8113) in vivo and in vitro

Dendritic cells (DCs), as primary antigen-presenting cells with the capacity to activate naïve T lymphocytes, are considered to be promising adjuvants for immunity against cancer. In this study, the effect of T lymphocyte-mediated immunity induced by a DC vaccine against Tca8113 cells in vivo and in vitro was evaluated. DCs were from human peripheral blood monocytes cultured in the presence of granulocyte-macrophage colony stimulating factor, interleukin 4 and/or tumour necrosis factor alpha, and stimulated with Tca8113 cell lysate prepared by the freeze-thaw method. The autologous T cells activated by these DCs were used in an in vitro MTT assay to detect their tumouricidal activity and investigated for their anti-tumour effect in vivo by administration to nude mice with implanted tumours (Tca8113). An adequate number of DCs were successfully generated from the monocytes. The T cells activated by the DC-based vaccine killed Tca8113 cells in vitro (P<0.01), postponed tumour doubling time of the implanted tumours in nude mice (P<0.01) and inhibited the growth of the tumours (P<0.05). These results show that DCs from monocytes induce a lymphocyte-mediated immune response against tongue squamous carcinoma, and could be used as a vehicle for tumour antigens.

Adenoviral vector-mediated RTVP-1 gene-modified tumor cell-based vaccine suppresses the development of experimental prostate cancer

We previously identified a novel p53 target gene, RTVP-1, that possesses unique cytotoxic and immunostimulatory activities which make it potentially useful for cancer gene therapy. To test the therapeutic potential of RTVP-1 in a gene-modified tumor cell-based vaccine model, we used an adenoviral vector capable of efficient transduction and expression of RTVP-1 (AdRTVP-1), together with a highly metastatic mouse prostate cancer cell line (178-2 BMA). A vaccine was prepared with 178-2 BMA cells transduced with AdRTVP-1 or a control adenoviral vector expressing beta-galactosidase (Adbetagal). After irradiation of the cells, syngeneic 129/Sv mice were vaccinated three times at weekly intervals. After 3 weeks, they were challenged with orthotopic 178-2 BMA cells. After 21 days, fewer than 60% of the RTVP-1-cell-vaccinated mice developed tumors compared to 100% of the control mice. The RTVP-1-cell vaccine significantly reduced primary tumor wet weight compared with control Adbetagal-cell vaccine (P<0.0001 at 7 and 14 days). Experimental metastasis to lung was also significantly reduced (P=0.0377), and survival significantly increased (P=0.0002). In addition, significantly increased NK and CTL activities were demonstrated in the AdRTVP-1-cell-vaccinated mice. These findings indicate that RTVP-1 gene-modified cell-based vaccines may be useful in the prevention of recurrent prostate cancer.

The enhancement of cell adherence and inducement of neurite outgrowth of dorsal root ganglia co-cultured with hyaluronic acid hydrogels modified with Nogo-66 receptor antagonist in vitro

Hyaluronic acid hydrogels modified with polyclonal anti-Nogo-66 receptor antibody were developed in order to promote regeneration in the injured CNS. These modified hydrogels were intended not only to deliver antibodies, but also to serve as a scaffold for neural regeneration following their implantation into injured tissue. Since unmodified hyaluronic acid-hydrogels do not support cell attachment, the gels were modified with polyclonal anti-Nogo-66 receptor with the aim of altering the surface properties of the gels in such a way as to improve neuronal adherence and survival. After evaluating the immobilization efficiency of the system, chicken dorsal root ganglia and dorsal root ganglia cells were planted on the surface of the modified gels to determine cell viability. Dorsal root ganglia were also cultured close to the gels in order to assay the inducement of neurite outgrowth. In dorsal root ganglia and cell viability assay, dorsal root ganglia and neuron cells could adhere to the modified hydrogels and survive well, but it did not happen to unmodified hydrogels. After 72 h, these attached cells were stained positively with immuno-staining for neurofilament. Neurite outgrowth inducement assay showed that the number and length of dorsal root ganglia neurites on the side toward modified hydrogels were significantly more than that on the opposite side (both P<0.01). The results reveal that hyaluronic acid-hydrogels modified with anti-Nogo-66 receptor can support neural cell attachment and survival in vitro. Furthermore, this system can greatly induce neurite outgrowth. The results also indicate that this modified hydrogels have potential to repair injury in the CNS.

Polymerase Chain Reaction-Based Analysis Using Deaminated DNA of Dodecamer Expansions in CSTB, Associated with Unverricht-Lundborg Myoclonus Epilepsy

Progressive myoclonus epilepsy of the Unverricht-Lundborg type is an autosomal recessive disorder that is characterized clinically by myoclonic seizures and ataxia. The majority of affected individuals carry repeat expansions of a dodecamer in the promoter region of the cystatin B gene. The unusually high GC content of this tract is refractory to conventional polymerase chain reaction (PCR), and, as a result, a circumventive procedure involving the deamination of DNA with sodium bisulfite has been proposed. This study evaluates the effectiveness of this deamination modification for the detection of dodecamer repeat variants. An analysis of 258 healthy Japanese individuals revealed an allele with four copies of the dodecamer repeat with a frequency of 0.01, in addition to the more commonly observed two and three copy repeat alleles. Homozygous repeat expansions 600 and 680 base pairs in length were detected in the analyses of two affected individuals. For these cases, sequencing, along with an alternative PCR-stutter formation, revealed 41 and 48 copies, respectively, of the dodecamer repeat. The complete conversion of C to T was observed in the expanded tracts, indicating that no methylation occurred at the CpG sites. Based on these results, it was concluded that the use of deaminated DNA allows for a precise analysis of consecutive GC tracts.

Room-temperature ferroelectricity in strained SrTiO3

Systems with a ferroelectric to paraelectric transition in the vicinity of room temperature are useful for devices. Adjusting the ferroelectric transition temperature (T(c)) is traditionally accomplished by chemical substitution-as in Ba(x)Sr(1-x)TiO(3), the material widely investigated for microwave devices in which the dielectric constant (epsilon(r)) at GHz frequencies is tuned by applying a quasi-static electric field. Heterogeneity associated with chemical substitution in such films, however, can broaden this phase transition by hundreds of degrees, which is detrimental to tunability and microwave device performance. An alternative way to adjust T(c) in ferroelectric films is strain. Here we show that epitaxial strain from a newly developed substrate can be harnessed to increase T(c) by hundreds of degrees and produce room-temperature ferroelectricity in strontium titanate, a material that is not normally ferroelectric at any temperature. This strain-induced enhancement in T(c) is the largest ever reported. Spatially resolved images of the local polarization state reveal a uniformity that far exceeds films tailored by chemical substitution. The high epsilon(r) at room temperature in these films (nearly 7,000 at 10 GHz) and its sharp dependence on electric field are promising for device applications.

Self-assembled single-crystal ferromagnetic iron nanowires formed by decomposition

Arrays of perpendicular ferromagnetic nanowires have recently attracted considerable interest for their potential use in many areas of advanced nanotechnology. We report a simple approach to create self-assembled nanowires of alpha-Fe through the decomposition of a suitably chosen perovskite. We illustrate the principle behind this approach using the reaction 2La(0.5)Sr(0.5)FeO(3) --> LaSrFeO(4) + Fe + O(2) that occurs during the deposition of La(0.5)Sr(0.5)FeO(3) under reducing conditions. This leads to the spontaneous formation of an array of single-crystalline alpha-Fe nanowires embedded in LaSrFeO(4) matrix, which grow perpendicular to the substrate and span the entire film thickness. The diameter and spacing of the nanowires are controlled directly by deposition temperature. The nanowires show uniaxial anisotropy normal to the film plane and magnetization close to that of bulk alpha-Fe. The high magnetization and sizable coercivity of the nanowires make them desirable for high-density data storage and other magnetic-device applications.

MICA, HLA-B haplotypic variation in five population groups of sub-Saharan African ancestry

The human major histocompatibility complex (MHC) class I chain-related gene A (MICA), located 46 kb centromeric to HLA-B, encodes a stress-inducible protein, which is a ligand for the NKG2D receptor. In addition to its primary role in immune surveillance, data suggest that MICA is involved in the immune response to transplants and in susceptibility to some diseases. In this study, 152 subjects from the Yoruba (n=74), Efik (n=32), and Igbo (n=46) tribes of southern Nigeria, 39 nationwide African-American stem cell donors, and 60 African-American individuals residing in the metropolitan Boston area were studied for MICA, HLA-B allelic variation, haplotypic diversity, and linkage disequilibrium (LD). MICA and HLA-B exhibited a high degree of genetic diversity among the populations studied. In particular, MICA allele and HLA-B-MICA haplotype frequencies and LD in the Efik and Igbo tribes were significantly different from the other study groups. HLA-B and MICA loci demonstrated significant global LD in all five populations (P-values &<0.00001). LD also varied in a haplotype-specific manner. A novel MICA allele was detected in the Boston population. These findings are important from an anthropologic perspective, and will inform future HLA-linked disease association studies in related ethnic groups of African-derived ancestry.

Features of double chamber bed and case study

A double chamber bed (DCB) was developed in China in 1980 and has been utilised in more than 500 setups. This paper introduces the structure and operation features of DCB, and also the unique structure of DCB leads to its perfect operation features. It can be also considered as the best option in reconstruction projects which can replace other types of ion exchangers, such as fixed bed, double cell fluidized-bed, multi-bed. Four reconstruction project cases were introduced, which were selected from more than twenty plants designed by us. Through the case study, it is concluded that DCB can not only be used to treat different sources of water (river and well), but can also be used to treat water with the ratio of transient hardness to total cation to be less than 0.5 and the ratio of strong to weak anion to be more than 7.0. These findings enlarge the scope of application of DCB.

Flow measurements via two-particle azimuthal correlations in Au + Au collisions at sqrt [s(NN)]=130 GeV

Two-particle azimuthal correlation functions are presented for charged hadrons produced in Au+Au collisions at the Relativistic Heavy Ion Collider (sqrt [s(NN)]=130 GeV). The measurements permit determination of elliptic flow without event-by-event estimation of the reaction plane. The extracted elliptic flow values (v2) show significant sensitivity to both the collision centrality and the transverse momenta of emitted hadrons, suggesting rapid thermalization and relatively strong velocity fields. When scaled by the eccentricity of the collision zone epsilon, the scaled elliptic flow shows little or no dependence on centrality for charged hadrons with relatively low p(T). A breakdown of this epsilon scaling is observed for charged hadrons with pT >1.0 GeV/c.

Measurement of Lambda and Lambda(macro) particles in Au+Au collisions at the square root of S(NN) = 130 GeV

We present results on the measurement of Lambda and Lambda(macro) production in Au+Au collisions at square root of (S (NN) = 130 GeV with the PHENIX detector at the Relativistic Heavy Ion Collider. The transverse momentum spectra were measured for minimum bias and for the 5% most central events. The Lambda;/Lambda ratios are constant as a function of p(T) and the number of participants. The measured net Lambda density is significantly larger than predicted by models based on hadronic strings (e.g., HIJING) but in approximate agreement with models which include the gluon-junction mechanism.

Net charge fluctuations in Au + Au interactions at sqrt[s(NN)]=130 GeV

Data from Au + Au interactions at sqrt[s(NN)]=130 GeV, obtained with the PHENIX detector at the Relativistic Heavy-Ion Collider, are used to investigate local net charge fluctuations among particles produced near midrapidity. According to recent suggestions, such fluctuations may carry information from the quark-gluon plasma. This analysis shows that the fluctuations are dominated by a stochastic distribution of particles, but are also sensitive to other effects, like global charge conservation and resonance decays.

Centrality dependence of pi(+/-), K(+/-), p, and (-)p production from sqrt[s(NN)] = 130 GeV Au + Au collisions at RHIC

Identified pi(+/-), K(+/-), p, and (-)p transverse momentum spectra at midrapidity in sqrt[s(NN)] = 130 GeV Au+Au collisions were measured by the PHENIX experiment at RHIC as a function of collision centrality. Average transverse momenta increase with the number of participating nucleons in a similar way for all particle species. Within errors, all midrapidity particle yields per participant are found to be increasing with the number of participating nucleons. There is an indication that K(+/-), p, and (-)p yields per participant increase faster than the pi(+/-) yields. In central collisions at high transverse momenta (p(T) > or =2 GeV/c), (-)p and p yields are comparable to the pi(+/-) yields.

Transverse-mass dependence of two-pion correlations in Au+Au collisions at square root[s(NN)] = 130 GeV

Two-pion correlations in square root[s(NN)] = 130 GeV Au+Au collisions at RHIC have been measured over a broad range of pair transverse momentum k(T) by the PHENIX experiment at RHIC. The k(T) dependent transverse radii are similar to results from heavy-ion collisions at square root[s(NN)] = 4.1, 4.9, and 17.3 GeV, whereas the longitudinal radius increases monotonically with beam energy. The ratio of the outwards to sidewards transverse radii (R(out)/R(side)) is consistent with unity and independent of k(T).

Measurement of single electrons and implications for charm production in Au+Au collisions at square root[s(NN)] = 130 GeV

Transverse momentum spectra of electrons from Au+Au collisions at square root[s(NN)] = 130 GeV have been measured at midrapidity by the PHENIX experiment at the Relativistic Heavy Ion Collider. The spectra show an excess above the background from photon conversions and light hadron decays. The electron signal is consistent with that expected from semileptonic decays of charm. The yield of the electron signal dN(e)/dy for p(T) > 0.8 GeV/c is 0.025+/-0.004(stat)+/-0.010(syst) in central collisions, and the corresponding charm cross section is 380+/-60(stat)+/-200(syst) microb per binary nucleon-nucleon collision.

Suppression of hadrons with large transverse momentum in central Au+Au collisions at root square[s(NN)] = 130 GeV

Transverse momentum spectra for charged hadrons and for neutral pions in the range 1 GeV/c<p(T)<5 GeV/c have been measured by the PHENIX experiment at RHIC in Au+Au collisions at root square[s(NN)] = 130 GeV. At high p(T) the spectra from peripheral nuclear collisions are consistent with scaling the spectra from p+p collisions by the average number of binary nucleon-nucleon collisions. The spectra from central collisions are significantly suppressed when compared to the binary-scaled p+p expectation, and also when compared to similarly binary-scaled peripheral collisions, indicating a novel nuclear-medium effect in central nuclear collisions at RHIC energies.

Preparation and characterisation of fluorescent chitosans using 9-anthraldehyde as fluorophore

Chitosans with chemical composition ranging from a fraction of N-acetylated units (F(A)) of 0.01 to 0.61 were used to prepare fluorescence labelled chitosans by reductive amination with 9-anthraldehyde. Fluorescent chitosans with a low theoretical degree of substitution (DS, 0.001-1%) were prepared, and the actual DS of the products were determined by UV and (1)H NMR spectroscopy. The fluorescence excitation and emission spectra of the chitosan with F(A) of 0.09 and DS 1% showed an excitation maximum at 254 nm and an emission maximum at 413 nm. The intrinsic viscosities ([eta]) of the fluorescent chitosans were compared to those of the original chitosans, showing that the derivatisation procedure lead only to a negligible decrease in [eta]. The conformation of these fluorescent chitosans with very low DS-values is not altered and they can conveniently be directly quantified by UV or fluorescence spectroscopy.

[Expression of bone morphogenetic protein (BMP)-2, 4 in mouse embryonic tooth during the bud stage]

OBJECTIVE

The purpose of this paper was to investigate the distributions of bone morphogenic protein (BMP)-2, 4 in the developing molars of mice during the bud stage and, the functional relationship between BMP-2 and BMP-4.

METHODS

The distribution of BMP-2, 4 were examined in developing mouse molars on the 14th (the 14th embryonic day), using monoclonal antibodies and immunohistochemistry methods.

RESULTS

BMP-2, 4 were detected both in the epithelial cells and dental mesenchyme cells.

CONCLUSION

There is a similar distribution pattern between BMP-2 and BMP-4. Therefore, there may be a functional relationship between BMP-2 and BMP-4 during the development of mouse embryonic teeth in the bud stage.

MICA genetic polymorphism and linkage disequilibrium with HLA-B in 29 African-American families

The human major histocompatibility complex (MHC) class I chain-related gene A ( MICA) is located 46 kb upstream of HLA-B and encodes a stress-inducible protein which displays a restricted pattern of tissue expression. MICA molecules interact with NKG2D, augmenting the activation of natural killer cells, CD8(+) alpha beta T cells, and gamma delta T cells. MICA allelic variation is thought to be associated with disease susceptibility and immune response to transplants. We investigated MICA allelic variations and linkage disequilibrium with HLA-A, B, and DRB1 loci on 110 parental haplotypes from 29 African-American families. PCR/sequence-specific oligonucleotide probing (SSOP) was used to define MICA polymorphisms in exons 2, 3, and 4. Ambiguous allelic combinations were resolved by sequencing exons 2, 3, and 4. Exon 5 polymorphisms were analyzed by size sequencing. For HLA-A, B and DRB1 typing, low-resolution PCR/SSOP and allelic PCR/sequence-specific priming techniques were used. Twelve MICA alleles were observed, the most frequent of which were MICA*008, MICA*004, and MICA*002, with gene frequencies of 28.2, 26.4, and 25.5%, respectively. Thirty-eight HLA-B- MICA haplotypic combinations were uncovered, 22 of which have not been reported in the HLA homozygous typing cell lines from the 10th International Histocompatibility Workshop. Significant positive linkage disequilibria were found in 8 HLA-B- MICA haplotypes. Furthermore, haplotypes bearing HLA-B*1503, *1801, *4901, *5201, *5301, and *5703 were found to segregate with at least two different MICA alleles. Our results provide new data about MICA genetic polymorphisms in African-Americans, which will form the basis for future studies of MICA alleles in allogeneic stem cell transplantation outcome.

[Effects of IL-8 on neutrophils under fluid shear]

OBJECTIVE

In order to elucidate the effect of IL-8 on neutrophils in a systematic and all-round way, we introduced an important physiological environment of neutrophils, fluid flow, into this study on the changes in some responses of neutrophils to IL-8 and the inter relationship of those responses under the conditions of different patterns of flow field.

METHODS

After using IL-8 and steady flow or sinusoidal-oscillate fluid shear rate simultaneously acting on separated neutrophils for one minute, we measured the expression of CD18, CD62L and the F-actin content with flow cytometry and measured the free calcium concentration inside cells ([Ca2+]i) with the fluorescent stain Fura2/AM using the fluorescent spectrophotometer.

RESULTS

It was found that flow shear stress could influence the expression of surface adherence molecule of neutrophils under the action of IL-8. CD18 surface expression increased, and CD62L shed under different flow shear rates, but no significant relationship of these changes with the intensity and pattern of shear stress was noted. On the other hand, the F-actin content in neutrophils under the action of shear stress and IL-8 decreased significantly at low shear rate and then gradually increased at high shear rate (600s -1) to the control value (without shear). The [Ca2+]i concentration under the action of shear stress and IL-8 decreased significantly at low shear rate followed by a quick increase at high shear rate.

CONCLUSION

The flow shear stress can influence the activation effects of IL-8 on neutrophils and regulate the magnitude of neutrophil reactions to a great extent, and among these reactions, the change of [Ca2+]i concentration is the most sensitive one and the greatest one. This is in consistence with its second messenger role in the signal transduction pathway. Our results could serve as a basis on which to understand better the mechanism of inflammatory reaction wherein the neutrophils under flow condition of blood are involved.

[A study on mRNA expression levels of integrin beta 1 during the healing process of mandibular fractures]

OBJECTIVE

The aim of this study was to investigate the spatial and temporal mRNA expression changes of integrin beta 1 during the healing process of mandibular fractures.

METHODS

The in situ hybridization was performed using digoxigenin-labeled integrin beta 1 mRNA oligonucleotide probe. During the healing process of mandibular fractures, the staining pattern of beta 1 mRNA was examined both spatially and time-dependently.

RESULTS

Integrin beta 1 was widely present in the cells of the fractured bone, especially in osteoblasts. The positive staining was observed in the cytoplasm and nucleolus of osteoblasts. After 7 days of fracture, the expression level of integrin beta 1 increased. The peak appeared between the 14th and the 30th day, and almost recovered to normal between the 60th and 90th day.

CONCLUSION

During the healing process of mandibular fracture, the expression level of integrin beta 1 in bone, especially in osteoblasts rose. It is suggested that integrin beta 1 may play an important role in the fracture healing process.

Green tea epigallocatechin gallate: a natural inhibitor of fatty-acid synthase

We discover that epigallocatechin gallate (EGCG) from green tea is an inhibitor of fatty-acid synthase (FAS) from chicken liver. Its inhibition of FAS is composed of reversible fast-binding inhibition, through which 52 microM EGCG can inhibit 50% of the activity of FAS, and irreversible slow-binding inactivation following saturation kinetics with the dissociation constant of 0.352 mM and limiting rate constant of 0.0168 min(-1). The marked inhibition of ketoacyl reduction shows that the inhibition is related to beta-ketoacyl reductase of FAS. The observable protection of NADPH and competitive inhibition of NADPH for ketoacyl reduction indicate that EGCG may compete with NADPH for the same binding site. The synthetic inhibitor C75 does not show obvious fast-binding inhibition, but does exhibit irreversible slow-binding biphasic inactivation, which is demonstrated to be a second-order reaction. That the inactivation by C75 is protected by malonyl-CoA indicates C75 is similar to cerulenin in being a covalent inactivator of the beta-ketoacyl synthase.

Urea and hypertonicity increase expression of heme oxygenase-1 in murine renal medullary cells

Epithelial cells derived from the mammalian kidney medulla are responsive to urea at the levels of signal transduction and gene regulation. Hybridization of RNA harvested from control- and urea-treated murine inner medullary collecting duct (mIMCD3) cells with a cDNA expression array encoding stress-responsive genes suggested that heme oxygenase (HO)-1 mRNA was upregulated by urea. RNase protection assay confirmed this upregulation; hypertonicity also increased HO-1 mRNA expression but neither hypertonic NaCl nor urea were effective in the nonrenal 3T3 cell line. The effect on HO-1 expression appeared to be transcriptionally mediated on the basis of mRNA half-life studies and reporter gene analyses using the promoters of both human and chicken HO-1. Although urea signaling resembles that of heavy metal signaling in other contexts, the effect of urea on HO-1 transcription was independent of the cadmium response element in this promoter. Urea-inducible HO-1 expression was sensitive to antioxidants but not to scavengers of nitric oxide. Urea also upregulated HO-1 protein expression and pharmacological inhibition of HO-1 action with zinc protoporphyrin-sensitized mIMCD3 cells to the adverse effects of hypertonicity but not to urea. Coupled with the prior observation of others that HO-1 expression increases along the renal corticomedullary gradient, these data suggest that HO-1 expression may comprise an element of the adaptive response to hypertonicity and/or urea in renal epithelial cells.

[An outline of spreading of Western mediciine into Yantai in modern age]

At the turn of the last century, side by side with the infiltration of religious culture from Western countries, western medicine spread into Yantai. The religious force, headed by American Presbyterian Mission, carried out charitable activities in the process of preaching and laid down the foundation for western medicine rooted in Yantai by establishing schools, education and training followers. They cultivated local physicians by first setting up clinics which had later transformed into hospitals. These are their major measures for building bases for spreading Christianity by foreigners. The Temple Hill Hospital set up by the American physician Oscar F. Hills in Yantai was a successful example of mutual promotion of missionary and medical activities which pushed forward the spreading and development of western medicine in Yantai.

Ultraviolet upconversion in thulium-doped fluorozirconate fiber observed under two-color excitation

Ultraviolet upconversion signals at 293, 351, and 366 nm were observed from thulium-doped fluorozirconate fiber pumped with a 458-nm Ar(+) laser. The upconversion signal's intensity was enhanced 5x when the fiber was simultaneously pumped with a 458-nm Ar(+) laser and a 585-nm dye laser. There is evidence of the formation of defect centers under simultaneous excitation by visible and near-infrared lasers (458 and 750 nm), and there is no evidence of color-center formation when both of the exciting beams are in the visible (458 and 585 nm).