Four new taraxastane-type triterpenoic acids from Cirsium setosum

Four new taraxastane-type triterpenoids acids 3β,22α-dihydroxy-20-taraxasten-30-oic acid (1), 3β-hydroxy-22-oxo-20-taraxasten-30-oic acid (2), 3-oxo-22α-hydroxy-20- taraxasten-30-oic acid (3), and 3β,19β-dihydroxy-20-taraxasten-30-oic acid (4) were isolated and characterized from Cirsium setosum (Willd.) MB. Their structures were determined by the combination of 1D and 2D NMR experiments ((1)H-(1)HCOSY, HSQC, HMBC and ROESY) and mass spectrometry. Compound 2 exhibited potent selective cytotoxicity against human ovarian cancer cell line A2780 with an IC50 value of 3.9 μM.

[Association of Crohn's disease with transcobalamin Ⅱ gene polymorphisms and serum homocysteine, folate and vitamin B12 levels in Chinese patients]

OBJECTIVE

To investigate the association of Crohn's disease (CD) with transcobalamin Ⅱ (TCN2) gene polymorphisms and serum homocysteine (Hcy), folate, and vitamin B12 levels in Chinese patients.

METHODS

In a total of 307 CD patients (CD group) and 574 healthy controls (control group) of Han ethnicity selected at 4 hospitals in Wenzhou between January 2007 and August 2015, TCN2 gene polymorphisms (rs1801198, C/G; rs9606756, A/G) in peripheral blood were determined using improved multiple ligase detection reaction (iMLDR). The Simplified Crohn's Disease Activity Index (CDAI) was applied to evaluate activity of CD. Eighty-eight CD patients and 138 age- and sex-matched controls were randomly selected from all the study subjects using computer-generated random numbers, in whom serum Hcy level was tested by enzymatic cycling assay, folate and vitamin B12 levels were examined by chemiluminescence immunoassay.

RESULTS

(1) The mutant allele (G) and genotype (CG+ GG) of rs1801198 were not significantly different between the CD group and the control group (both P>0.05), but more prevalent in patients with stricturing CD than in controls (65.75% vs 56.10%, 93.15% vs 82.40%, both P<0.05). The frequencies of mutant allele (G) and heterozygous genotype (AG) of rs9606756 were higher in CD patients than in controls (2.44% vs 1.05%, 4.89% vs 2.09%, both P<0.05), also higher in patients with stricturing CD or ileocolonic CD compared with controls (stricturing CD: 4.79% vs 1.05%, 9.59% vs 2.09%; ileocolonic CD: 3.18% vs 1.05%, 6.36% vs 2.09%; all P<0.05). The two polymorphic loci (rs1801198 and rs9606756) were shown to be in a weak linkage disequilibrium. The frequency of haplotype (GG) was higher in the CD patients than in the controls (2.23% vs 0.81%, P<0.05). (2) When compared with the controls, the serum Hcy level was higher in the CD patients (P=0.023), whereas the folate and vitamin B12 levels were decreased in the CD patients (both P<0.001). The prevalence of hyperhomocysteinemia (Hcy >15 μmol/L), folate deficiency (folate <4 μg/L) and vitamin B12 deficiency (<203 ng/L) were higher in the CD patients than in the controls (18.18% vs 4.35%, 27.27% vs 5.07%, 31.82% vs 5.07%, all P<0.01). Compared to the patients at remission stage (CDAI<5), the serum Hcy level was increased in those at active stage (CDAI≥5) (P=0.005), while the folate and vitamin B12 levels were decreased in the patients ate active stage (both P<0.05). (3) According to the results of multivariate linear regression analysis, average Hcy level in the CD patients was negatively associated with folate level (β=-0.494, P<0.001), while positively correlated with percentage of neutrophils (β=0.294, P=0.004). Unconditional Logistic regression showed that both folate deficiency and vitamin B12 deficiency were independent risk factors for CD (OR=5.415, OR=7.112, both P<0.001).

CONCLUSIONS

TCN2 rs1801198 mutation might be associated with increased risk of stricturing CD. TCN2 rs9606756 mutation might be a potential functional locus to affect CD susceptibility. Individuals carrying the haplotype (GG) formed by TCN2 (rs1801198 and rs9606756) seem to be at higher risk of developing CD. Hyperhomocysteinemia, folate deficiency, and vitamin B12 deficiency are prevalent in this cohort of CD patients of Han ethnicity from Zhejiang province. Both folate deficiency and vitamin B12 deficiency are independent risk factors for CD.

Nutritional effects on the mycelial growth and enzymatic activity of Isaria farinosa, and Hepialus larvae growth

AIMS

To investigate the nutritional requirements of the mycelial growth and pathogenesis-related enzymatic activity on Isaria farinosa and the nutritional effect of fungus on its host Hepialus larvae.

METHODS AND RESULTS

Sixteen carbon sources, 16 nitrogen sources and 9 vitamin combinations were tested. The nutritional conditions that significantly prevented I. farinosa pathogenesis were selected as feed additives for rearing Hepialus larvae. Citric acid significantly inhibited the growth of I. farinosa and the activity of three enzymes. l-histidine and l-aspartic acid significantly reduced the dry weights of mycelia and their protease and lipase activities. Vitamin combination that lacked VB 1 significantly increased the growth of I. farinosa and enhanced its chitinase and lipase activities. l-aspartic acid, VB 1 or a combination of them were beneficial for maintaining the larvae survival rate and decreasing the disease rate. The result provides new insight to develop a nutrition-based strategy to control fungal epidemics during insect rearing.

CONCLUSIONS

The ability of some specific nutrients to inhibit mycelial growth and enzymatic activity can prevent epidemics of fungal disease.

SIGNIFICANCE AND IMPACT OF THE STUDY

These results will aid in the development of nutrition-based strategies to control entomopathogenic fungal epidemics during the large-scale rearing of insects.

A self-contrast approach to evaluate the inhibitory effect of chrysosplenetin, in the absence and presence of artemisinin, on the in vivo P-glycoprotein-mediated digoxin transport activity

In this study, we used a self-contrast method, which excluded the individual difference, to evaluate the inhibitory effect of chrysosplentin (CHR) in the presence or absence of artemisinin (ART) on the P-glycoprotein (P-gp) transport activity. A sensitive and rapid UHPLC-MS/MS method was applied for quantification of digoxin, a P-gp-specific substrate, in rat plasma. A pharmacokinetic study was carried out: first after an oral administration of digoxin at a dose of 0.09 mg/kg (first period), followed by a 20-day wash-out, then after another administration of digoxin (second period). During the second period, test compounds were orally given three times per day for seven consecutive days. Results showed that the t1/2 of digoxin in all the groups had no significant difference between the first and second periods. The AUC0-24 , Cmax , tmax , and Clz /F of the negative control and ART alone groups showed no difference. However, the AUC0-24 and Cmax in the CHR alone, CHR-ART (1:2) and verapamil (positive control) groups showed 2.34-, 3.04-, 1.79-, and 1.81-, 1.99-, 2.06-fold increases along with 3.50-, 3.84- and 4.76-fold decreases for CLz /F, respectively. The tmax in the CHR-ART (1:2) group increased 3.73-fold. In conclusion, our self-contrast study suggested that CHR, especially when combined with ART in a ratio of 1:2, inhibited P-gp activity while ART alone has no effect. Copyright © 2016 John Wiley & Sons, Ltd.

[Efficacy analysis of radiofrequency ablation combined with 125I seed for multiple nodular hepatocellular carcinoma]

OBJECTIVE

To investigate the clinical efficacy of radiofrequency ablation(RFA)combined with (125)I seed in patients with multiple nodular hepatocellular carcinoma(HCC).

METHODS

The clinical data of 47 patients with multiple nodular HCC confirmed clinically or pathologically in the Fifth Affiliated Hospital of Wenzhou Medical University between January 2009 and September 2014 were retrospectively analyzed. All patients were divided into two groups depending on treatment: RFA group(n=29); RFA combined with (125)I seed group(n=18). Survival time was estimated with the Kaplan-Meier analysis. The survival curve was compared by Log-rank test.

RESULTS

The clinical data and tumor situation of patients between two groups did not show significant differences. The follow-up time ranged from 2 to 55 months. At the end of the study, the median progression-free survival of two groups were 18 months and 11 months, and the differences were statistically significant(P=0.036). The overall survival rates in RFA combined with (125)I seed group at 1, 2, and 3 years (94.4%, 78.0%, 66.8%, respectively) were higher than those in RFA group (88.5%, 68.6%, 57.1%, respectively). However, the differences between the two groups were not statistically significant(P=0.554).

CONCLUSIONS

For multiple nodular HCC, RFA combined with (125)I seed can prolong progression-free survival, have an advantage in local control rate, and is better than single RFA at short-term curative effect.However, its long-term outcomes should be further explored by a large-sample, multi-center and randomized trial.

Unified Strouhal-Reynolds number relationship for laminar vortex streets generated by different-shaped obstacles

A structure-based Strouhal-Reynolds number relationship, St=1/(A+B/Re), has been recently proposed based on observations of laminar vortex shedding from circular cylinders in a flowing soap film. Since the new St-Re relation was derived from a general physical consideration, it raises the possibility that it may be applicable to vortex shedding from bodies other than circular ones. The work presented herein provides experimental evidence that this is the case. Our measurements also show that, in the asymptotic limit (Re→∞), St(∞)=1/A≃0.21 is constant independent of rod shapes, leaving B the only parameter that is shape dependent.

Chemotherapy combined with target drugs in the treatment of advanced colorectal cancer: a meta-analysis based on Chinese patients

BACKGROUND

Colorectal carcinoma is one of most diagnosed solid malignant carcinoma. The chemotherapy combined with target drugs in the treatment of advanced colorectal cancer in not conclusive.

METHODS

The clinical studies reporting the activity and adverse events between chemotherapy alone versus chemotherapy combined with anti-epidermal growth factor receptor drugs were screened in the databases of Medline, the Cochrane Library, Wanfang and CNKI and included in this meta-analysis. The risk ratio (RR) and its 95% confidence interval (CI) for treatment response and adverse events were pooled by random or fixed effect model.

RESULTS

A total of 10 clinical studies reporting chemotherapy combined with the target in the treatment of advanced colorectal cancer were included in this study. The pooled RR was 3.26 (95% CI: 1.74-6.11, P < 0.05), 1.49 (95% CI: 1.23-1.80) and 1.65 (95% CI: 1.37-1.98) for complete response (CR), partial response and objective response rate, respectively. For nausea and vomiting events, the RR was 1.62 (95% CI: 1.33-1.97, P < 0.05) indicating higher incidence of nausea and vomiting was observed in the combined group compared with chemotherapy alone. However, the diarrhea (RR = 1.10, 95% CI: 0.86-1.42, P > 0.05), liver function damage (RR = 1.03, 95% CI: 0.74-1.42), myelosuppression (RR = 1.04, 95% CI: 0.83-1.31) and neurotoxicity (RR = 1.12, 95% CI: 0.93-1.35) were not different between the two groups.

CONCLUSION

For Chinese patients with advanced colorectal cancer, chemotherapy combined with target drug can improve the response rate, but also increase the risk of nausea and vomiting.

Impact of enteral nutrition on postoperative immune function and nutritional status

We studied the effects of enteral nutrition (EN) support initiated 1 week before surgery on postoperative nutritional status, immune function, and inflammatory response in gastric cancer patients. A total of 200 gastric cancer patients were randomly divided into two groups: EN starting 1 week before surgery (study group) and EN starting early after surgery (control group). The two groups received EN support, following different therapeutic schedules, until the 9th day after operation. In the patients, body weight, skinfold thickness, upper-arm circumference, white blood cell count, albumin, prealbumin, C-reactive protein, peripheral immunoglobulins (IgA, IgG, and IgM), T lymphocyte subsets, interleukin-6, and tumor necrosis factor-α were measured 10 days before and after surgery and on the first day after surgery. There was no statistically significant difference in the results of recovery time of passage of gas by anus, abdominal distension, stomachache, blood glucose, hepatic and renal functions, and electrolytes between the two groups of patients (P > 0. 05). Adverse reactions occurred to both groups at 1 and 2 days after operation. Such conditions was improved after the intravenous drip rate was adjusted. The albumin and prealbumin levels of the patients in both groups decreased at 1 day after operation (P < 0. 05). The levels rose when the research was finished (P < 0. 05). The prealbumin level of the study group was higher than that of the control group at 10 days after operation (P < 0. 05). The IgG level of the study group was higher than that of the control group at 10 days after operation (P < 0. 05). The two groups of inflammatory reaction indicators of the study group were lower than those of the control group at 10 days after operation (P < 0. 05). This study indicates that appropriate preoperative EN support for gastric cancer patients can improve their postoperative nutritional status and immune function, can reduce inflammatory response, and is more conducive to the recovery of patients.

Astrocytic Cx 43 and Cx 40 in the mouse hippocampus during and after pilocarpine-induced status epilepticus

Astrocytes have now been well accepted to play important roles in epileptogenesis by controlling gliotransmitter release and neuronal excitability, contributing to blood-brain barrier dysfunction and involving in brain inflammation. Recent studies indicate that abnormal expression of gap junction protein connexin (Cx) may also be a contributing factor for seizure generation. To further address this issue, we investigated the progressive changes of Cx 43 and Cx 40 in the mouse hippocampus at 4 h, 1 day, 1 week and 2 months during and after pilocarpine-induced status epilepticus (PISE). The co-localization of Cx 43 and Cx 40 with glial fibrillary acidic protein (GFAP) was also examined. We observed that Cx 43 and Cx 40 protein expression remained unaltered at 4 h during and at 1 day (acute stage) after PISE. However, their expression was significantly increased in CA1 and CA3 areas and in the dentate gyrus at 1 week (latent stage) and 2 months (chronic stage) after PISE. Double immunofluorescence labeling indicated the localization of Cx 43 and Cx 40 in astrocytes. Combined with progressive neuronal loss in the mouse hippocampus, our results suggest that the increase in gap junctions in the neuronoglial syncytium of reactive astrocytes may be implicated in synchronization of hippocampal hyperactivity leading to neuronal loss and epileptogenesis.

The gene expression patterns of BMPR2, EP300, TGFβ2, and TNFAIP3 in B-Lymphoma cells

OBJECTIVE

The results of a previous study showed that a clear dysregulation was evident in the global gene expression of the BCL11A-suppressed B-lymphoma cells. In this study, the bone morphogenetic protein receptor, type II (BMPR2), E1A binding protein p300 (EP300), transforming growth factor-β2 (TGFβ2), and tumor necrosis factor, and alpha-induced protein 3 (TNFAIP3) gene expression patterns in B-cell malignancies were studied.

METHODS

The relative expression levels of BMPR2, EP300, TGFβ2, and TNFAIP3 mRNA in B-lymphoma cell lines, myeloid cell lines, as well as in cells from healthy volunteers, were determined by real-time quantitative reverse transcript-polymerase chain reaction (qRT-PCR) with SYBR Green Dye. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as reference.

RESULTS

The expression level of TGFβ2 mRNA in B-lymphoma cell lines was significantly higher than those in the cells from the healthy control (P<0.05). However, the expression level of TNFAIP3 mRNA in B-malignant cells was significantly lower than that of the healthy control (P<0.05). The expression levels of BMPR2 and EP300 mRNA showed no significant difference between B-malignant cell lines and the healthy group (P>0.05). In B-lymphoma cell lines, correlation analyses revealed that the expression of BMPR2 and TNFAIP3 (r=0.882, P=0.04) had significant positive relation. The expression levels of BMPR2, EP300, and TNFAIP3 mRNA in cell lines from myeloid leukemia were significantly lower than those in the cells from the healthy control (P<0.05). The expression levels of TGFβ2 mRNA showed no significant difference between myeloid leukemia cell lines and the healthy control or B-malignant cell lines (P>0.05). The expression levels of BMPR2, EP300, and TNFAIP3 mRNA in B-lymphoma cells were significantly higher than those of the myeloid leukemia cells (P<0.05).

CONCLUSION

Different expression patterns of BMPR2, EP300, TGFβ2, and TNFAIP3 genes in B-lymphoma cells exist.

A compact two-way high-power microwave combiner

A compact 2-way high-power microwave (HPM) waveguide combiner as an important equipment to realize the coherent microwave combination was theoretically designed, built, and proof-of-principle experimentally tested. The theoretical and experimental S-parameters are basically consistent with each other: return loss <-25 dB, and the isolation degree between 2-channels of the HPM combiner >25 dB to avoid the inter-modulating between the HPM sources. The C-band HPM experiment was carried out, and the power capacity of the HPM combiner was demonstrated to reach multi-gigawatts.

The biophysical property of A549 cells transferred by VEGF-D

Vascular endothelial growth factor-D (VEGF-D) together with VEGF-C is considered to be associated with lymphangiogenesis and angiogenesis and involve in tumorization. This study aims to investigate the influence of exogenous VEGF-D gene on the biophysical property of cell surface of lung adenocarcinoma cell line. A panel of lung adenocarcinoma cell lines were examined the expression of VEGF-D and VEGF-C by real-time PCR. The VEGF-D recombinant plasmid containing enhanced green fluorescence protein (EGFP) was constructed and transfected to the cell line with no expression of VEGF-D and confirmed by real-time PCR and Western blot analysis. Topographic images of cells were obtained by using atomic force microscope (AFM) in contact mode. Unlike VEGF-C, VEGF-D was found to have a very low expression or undetectable expression in lung adenocarcinoma cell lines. The VEGF-D recombinant plasmid had been constructed successfully and was transferred into the human lung adenocarcinoma cell line A549 cells which had no endogenous expression of VEGF-D, and exogenous VEGF-D could be detected in mRNA and protein expression levels in the gene modified cells, while the VEGF-C gene expression had no change after VEGF-D transfection. After transfection, the irregular microspikes or nano clusters could observe on the surface of A549 cells, and VEGF-D transfected A549 cells became more rigid. The exogenous VEGF-D gene might cause the remarkable biophysical architectural changes in the A549 cells, which might as a novel biomarker for evaluation of its biological function.

[Autotoxicity of aqueous extracts from plant of cultivated Astragalus membranaceus var. mongholicus]

OBJECTIVE

To exploring the relationship between continuous cropping obstacle and autotoxicity of Astragalus membranaceus var. mongholicus, autotoxic effect of plant aqueous extract were determined.

METHODS

Distilled water (CK), aqueous extract of plant, including root, stem and leaf (12.5, 25, 50 and 100 mg/mL respectively)were applied to testing their effect on early growth of Astragalus membranaceus var. mongholicus. Specifically, seed germination rate, germination index, emergence rate, elongation of radical and embryo, and seedling vigor index were determined.

RESULTS

The aqueous extract of root, stem, and leaf at 25 mg/mL significantly inhibited the seed germination and seedling growth of Astragalus membranaceus var. mongholicus, and this inhibitory effect generally increased with the increase of the concentration of aqueous extracts. To the comprehensive allelopathic effect, the extracts from Astragalus membranaceus var. mongholicus stem were more inhibitory than those from leaf and root. The germination index and seedling vigor index were more sensitive to extract than other determined parameters.

CONCLUSION

Aqueous extracts from Astragalus membranaceus var. mongholicus plant gave inhibitory effects on Astragalus. membranaceus var. mongholicus germination and seedling growth, and this inhibitory effect generally increased with the increases of aqueous extract concentration at a certain ranges. In conclusion, there is an autotoxicity in continuous cropping of Astragalus membranaceus var. mongholicus.

A new periplogenin cardenolide from the seeds of Antiaris toxicaria

A new periplogenin cardenolide, periplogulcoside (1), together with three known cardenolides, was isolated from the seeds of Antiaris toxicaria. The structure of the new compound was characterized as periplogenin-3-O-β-D-glucopyranosyl-(1 → 4)-β-D-glucopyranoside (1) by spectroscopic methods including 1D and 2D NMR, HR-TOF-MS, and CD spectrometry, and the known compounds were identified by comparison of their NMR and HR-TOF-MS data with those reported in the literature. Compound 1 showed significant cytotoxicity against Hela and HepG-2 cell lines.

[Determination of chrysosplenetin, metabolic inhibitor of artemisinin, in rat plasma by UPLC-ms/MS and study on its pharmacokinetics]

OBJECTIVE

The study aimed to develop the assay of chrysosplenetin (CHR), a metabolic inhibitor of artemisinin by UPLC-MS/MS in rat plasma and investigate the pharmacokinetics parameters of CHR.

METHOD

The plasma samples were precipitated by acetonitrile to remove the proteins. Separation was carried out on a Shim-pack XR-ODS C,18(2. 0 mm x 100 mm, 2. 2 micromp.m) column using a mobile phase containing methanol-0. 1% formic acid (87:13) using by diazepam as internal standard. Mass spectrometer with electrospray ionization (ESI) operated in the positive ion mode was used for analysis. Total analysis time was 2 min.

RESULT

The assay was linear in the range 5-5 000 microg L-1 (r =0. 999 3) with recoveries in the range from 69. 0% to 81.2% and satisfied inter-, intra- precision and accuracy. CHR after oral administration is not easy to absorb with double or multimodal peak phenomenon. The t1/2 of CHR after intravenous injection was very short and that of low, medium, and high dosage was (17. 01 +/- 8. 06) , (24. 62 +/- 4. 59), (28. 46+/- 4. 63) min, respectively.

CONCLUSION

The developed method was special, rapid, and sensitive for determination of CHR pharmacokinetics. [Key words] UPLC-MS/MS; chrysosplenetin; pharmacokinetics; plasma; rat

Cytotoxic monacolin analogs from Monascus purpureus-fermented rice

Two new monacolin analogs, monacolins O (1) and P (2), along with three known analogs, have been isolated from the ethanolic extract of Monascus purpureus-fermented rice. Their structures and absolute configurations were elucidated by spectroscopic methods, especially 2D NMR and CD spectral analyses as well as chemical method. Both 1 and 2 were tested against five tumor cell lines, and compound 1 exhibited selective cytotoxic activity against A2780 and A549 cell lines, with IC50 values of 3.7 and 8.0 μM, respectively.

[Separation and identification of endophytic fungi from desert plant Cynanchum komarovii]

OBJECTIVE

The research aimed to investigate the entophytic fungal community of Cynanchum Komarrovii, including the biodiversity in different organs and the correlations with ecological environment. Endophytic fungi with patent bioactivity were also rapidly screened.

METHOD

PDA medium was used to isolate and purify the endophytic fungi from C. komarovii living in Shaanxi and Ningxia district, respectively. The strains were identified based on the morphological characteristics of the fungi and similarity of 5.8S gene and internal transcribed spacer (ITS) sequence. Pyriculaia oryzae model was applied to preliminarily screen the active fungi.

RESULT

Ninety-four strains of endophytic fungi were isolated and identified to 9 species, 13 genera, 9 families and 6 orders, among them, 47 strains were from the plants living in Ningxia. And then, 5 of them were isolated from roots, 14 from branches, and 28 from leaves. They were identified belonging to 8 species, 9 genera, 5 families and 4 orders. Additionally, 47 strains were from the plants living in Shaanxi. 16 were isolated from the roots, 18 from branches, 13 from leaves. They were identified belonging to 5 species, 8 genera, 6 families and 4 orders. By preliminary screening, 18 strains of endophytes completely inhibited the germination of conidium, which showed a potential bioactivity for these fungi. Both N4 and S17 strains had stronger growth inhibition effect.

CONCLUSION

Endophytic fungi from desert plant C. komarovii have the feature of diversity. Different geographical environment and type of organizations lead to the significant difference on the quantity and the species composition. Most of fungi in Ningxia C. komarovii distribute in leaves. However, most of those in Shaanxi C. komarovii distribute in stems and leaves. It also indicated that endophytes from C. komarovii had a strong antifungal activity.

trans-Dibromidotetra-kis-(pyridine-κN)ruthenium(II)

The title complex, [RuBr₂(C₅H₅N)₄], contains two independent complex mol­ecules in each of which the Ru^II atom is located on a site of 222 symmetry and has a distorted octa­hedral coordination geometry with four pyridine N atoms and two Br atoms. The Br aroms are trans-disposed as a result of symmetry.

Allo-HSCT for acute leukemia of ambiguous lineage in adults: the comparison between standard conditioning and intensified conditioning regimens

Knowledge concerning the clinical and biological characteristics of acute leukemia of ambiguous lineage (ALAL) is limited so that there has been a lack of uniformity in treatment. In this report, we retrospectively investigated the effect of intensified conditioning on adult ALAL undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). A total of 59 patients with ALAL (male in 37 cases and female in 22 cases) were consecutively enrolled in the data analyses. Twenty-four patients received the standard conditioning (total body irradiation (TBI) + cyclophosphamide (CY) or busulfan + CY protocol) and 35 received the intensified conditioning (TBI + CY + etoposide or fludarabine + cytarabine plus TBI + CY + etoposide protocol). Five-year transplant-related mortality was 17.6 ± 9.6 % and 25.5 ± 8.0 %, the 5-year overall survival (OS) post-transplantation was 23.8 ± 8.9 % and 64.0 ± 8.4 %, disease-free survival was 16.7 ± 7.6 % and 55.8 ± 9.4 %, the 5-year cumulative incidence of relapse was 80.8 ± 8.5 % and 28.8 ± 9.9 %, respectively, in the standard and the intensified group (P = 0.380, P = 0.029, P = 0.005, and P < 0.001). Both univariate and multivariate analysis indicated that the intensified conditioning regimen and acute graft-versus-host disease were favorable factors to reduce the relapse. The younger patients, patients with CR at the time of transplantation, and the intensified conditioning regimen were favorable factors to elevate the survival. In conclusion, intensified conditioning regimens followed by allo-HSCT might improve long-term survival and decrease relapse of leukemia in adult ALAL compared to the standard conditioning regimens.

Structure-activity relationship of a guanine-free oligodeoxynucleotide as immunopotent inhibitor

Excessive innate immune response could contribute to the pathogenesis of inflammatory and autoimmune diseases. It is required to develop agents to inhibit the overwhelming innate immune response. SAT05f, an inhibitory ODN with CCT repeat sequence found in human microsatellite DNA, has been demonstrated to down-regulate TLR7/9-mediated innate immune response, protect mice from D-GalN/CpG ODN induced lethal shock, and reduce anti-ssDNA antibody level in the lupus-prone mice induced by chronic graft versus host disease (cGVHD). In this article, to explore the structure-activity relationship of SAT05f, we designed and synthesized a series of ODNs based on the sequence of SAT05f by changing repeat number of the CCT unit, substituting CCT unit with AAG at 3' end or 5' end or in the middle and by forming hairpin at 5' or 3' end, and tested their inhibitory effect on the CpG ODN induced proliferation and TNF-α production in murine immune cells. The results indicated that 1) at least 8 CCT units were required for a CCT repeat ODN to display its inhibitory activity; 2) CCT unit at 3' end of SAT05f was necessary for its full inhibitory activity; and 3) 5' end of SAT05f could be modified to design a more potent SAT05f derived inhibitory ODN. The data provided here would be helpful for finding a potent inhibitory ODN as a candidate medicament for the treatment of diseases associated with over-activated innate immune response.

Serum prolactin levels and the acute-phase efficacy in drug-naïve schizophrenia treated with ziprasidone and olanzapine (translated version)

OBJECTIVES. To study the efficacy and associated serum prolactin levels of ziprasidone and olanzapine treatment in drug-naïve schizophrenia patients. METHODS. All 78 inpatients with drug-naïve schizophrenia were recruited from the Department of Psychology, The Third Affiliated Hospital of Sun Yat-sen University. They were divided into either olanzapine group (n = 49 [24 men, 25 women]; mean [standard deviation] age, 24 [6] years) or ziprasidone group (n = 29 [14 men, 15 women]; mean [standard deviation] age, 23 [7] years), all of whom were treated for 4 weeks. The serum prolactin level, the Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression-Severity (CGI-S), and Clinical Global Impression-Improvement scores were measured before and at the end of treatment. RESULTS. In the olanzapine group, the respective mean (standard deviation) PANSS and CGI-S scores after the treatment (62 ± 15 and 3 ± 1) were significantly lower than those before the treatment (104 ± 14 and 6 ± 1) [p < 0.01]. In the ziprasidone group, the corresponding scores after the treatment (75 ± 20 and 4 ± 1) were also significantly lower than those before the treatment (104 ± 17 and 6 ± 1) [p < 0.01]. The decreases in mean (standard deviation) PANSS total (42 ± 17) and PANSS positive scores (12 ± 6) in the olanzapine group were significantly higher than those in the ziprasidone group (29 ± 12 and 6 ± 4, respectively) [p < 0.01]. The increase of serum prolactin in the ziprasidone female group (47 ± 51 µg/L) was significantly higher than that in the ziprasidone male group (17 ± 11 µg/L), the olanzapine male group (5 ± 16 µg/L), and the olanzapine female group (21 ± 34 µg/L) [p < 0.05]. CONCLUSIONS. Both ziprasidone and olanzapine are effective for treating drug-naïve acute schizophrenia, but olanzapine was superior to ziprasidone in terms of positive and general psychopathological symptoms. In women, ziprasidone was associated with greater changes in prolactin level than olanzapine.

Origin of strong white electroluminescence from dense Si nanodots embedded in silicon nitride

Strong white electroluminescence (EL) from SiN-based devices containing Si nanodots with a density of more than 4.6×10(12)cm(2) was investigated. The white EL illustrates enhanced light emission with increasing applied voltage and can be divided into two components, a dominant peak at ~710 nm and weak one at ~550 nm, which are close to those of the PL spectra optically pumped by the 325 and 488 nm lines, respectively. Based on the PL characteristics, we propose that the dominant EL band arises from the band-to-band recombination in the dense Si nanodots where quantum confinement plays a decisive role in the light emission, whereas the weak EL band originates from the radiative Si dangling bond (K⁰) centers in the silicon nitride matrix.

Synthesis of crystalline beta-FeSi2 under high-temperature and high-pressure

In this paper, we report the synthesis of crystalline beta-FeSi2 via the reaction of Si and Fe powders under high-temperature and high-pressure. X-ray diffraction and Raman scattering results confirm formation of the beta-FeSi2 phase. Scanning electron microscopy, high-resolution transmission electron microscopy, and selected-area electron diffraction patterns show that the beta-FeSi2 phase coexists with Si phase with small nanocrystal sizes. The formation of the beta-FeSi2 phase is a result of Si diffusion into Fe region. The obtained results suggest that the removal of Si phase can be reached through increasing Fe content and prolonging the duration of high-pressure thermal treatment.

Oxygen vacancy density-dependent transformation from infrared to Raman active vibration mode in SnO2 nanostructures

Raman spectra acquired from spherical, cubic, and cuboid SnO2 nanocrystals (NCs) reveal a morphologically independent Raman mode at ∼302 cm(-1). The frequency of this mode is slightly affected by the NC size, but the intensity increases obviously with decreasing NC size. By considering the dipole changes induced by oxygen vacancies and derivation based on the density functional theory and phonon confinement model, an oxygen vacancy density larger than 6% is shown to be responsible for the transformation of the IR to Raman active vibration mode, and the intensity enhancement is due to strong phonon confinement.

Anthraquinones from the roots of Knoxia valerianoides

Five new 9,10-anthraquinones (1-5) were isolated from an ethanol extract of the roots of Knoxia valerianoides. Their structures including absolute configuration of 1 were determined by spectroscopic analysis. Compounds 4 and 5 showed moderate activity against nitrogen oxide production in macrophages induced by lipopolysaccharide, at 10(- 5) M, with inhibition ratios of 50.4 ± 3.6 and 41.7 ± 2.1%, respectively.

Mn²+-bonded reduced graphene oxide with strong radiative recombination in broad visible range caused by resonant energy transfer

The photoluminescence (PL) characteristics of Mn(2+)-bonded reduced graphene oxide (rGO) are studied in details. The Mn(2+)-bonded rGO is synthesized using MnO(2)-decorated GO as the intermediate products and ideal tunable PL is obtained by enhancing the long-wavelength (450-550 nm) emission. The PL spectra excited by different wavelengths are analyzed to elucidate the mechanism, and the resonant energy transfer between Mn(2+) and sp(2) clusters of the rGO appears to be responsible for the enhanced long-wavelength emission. To examine the effect of Mn(2+) on the long-wavelength emission from the Mn(2+)-bonded rGO, the PL characteristics of Mn(2+)-bonded rGO with smaller Mn concentrations are studied and weaker emission is observed. Our theoretical calculation corroborates the experimental results.

IL-17RA aptamer-mediated repression of IL-6 inhibits synovium inflammation in a murine model of osteoarthritis

OBJECTIVE

Generate DNA aptamers to inhibit IL-17RA-mediated synovial inflammation in an experimental mouse model of osteoarthritis (OA).

METHODS

A novel cell-SELEX method was applied to obtain DNA aptamers specific for IL-17RA. A single-stranded (ss) DNA library with four(30) probes was synthesised. By incubating this library with NIH3T3 cells, we collected DNA ligands that could bind the cell surface. The collected ligands were incubated with IL-17RA-deficient NIH3T3 cells, and unbound ssDNA was harvested from the supernatant for the next round of selection. After 12 cycles, specific aptamers against IL-17RA were generated. For animal experiments, a meniscectomy was performed on Balb/C mice to generate an animal model of OA. Mice received weekly intra-articular (i.a.) injections of aptamers or control treatments for 6 weeks. Synovial membranes were evaluated by histomorphology and the mRNAs of critical inflammatory cytokines were measured by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

An aptamer termed RA10-6 was obtained that could efficiently block IL-17 binding to IL-17RA in a dose-dependent manner in vitro. Histological examination and quantitative RT-PCR results showed that OA mice that injected with RA10-6, especially in combination with celecoxib demonstrated inhibition of synovial thickening and reduction in IL-6 levels in the synovial tissue.

CONCLUSION

Our results suggest that RA10-6 can inhibit synovial inflammation by blocking IL-17/IL-17RA-mediated IL-6 expression. RA10-6 acted synergistically with celecoxib to inhibit IL-6 expression in synovial tissues. Thus, aptamers targeting IL-17RA might serve as potent adjunctive agents for the early treatment of OA.

[Spectral study on the interaction of [Cu(DPPZ)(L-Ser)]+ complex with DNA and its analytical application]

The characteristics of resonance light scattering (RLS), UV-visible absorption spectra and fluorescence spectra of [Cu(DPPZ)(L-Ser)]+ with DNA were studied and a RLS method for the determination of DNA was established. [Cu(DPPZ) (L-Ser)]+ could assemble on the surface of DNA through intercalation, and enhanced the RLS of DNA in the tris buffer of pH 7. 2. The maximum resonance light scattering peak appeared at 400 nm. Under the optimum conditions, the enhanced intensity of RLS was proportional to the concentration of DNA over the range of 0.42 - 4.2 ng x mL(-1), with a detection limit (3sigma/k) of 0.29 ng x mL(-1). The method was used for the determination of DNA samples with the recoveries between 97.8% and 106%.

Green light stimulates terahertz emission from mesocrystal microspheres

The discovery of efficient sources of terahertz radiation has been exploited in imaging applications, and developing a nanoscale terahertz source could lead to additional applications. High-frequency mechanical vibrations of charged nanostructures can lead to radiative emission, and vibrations at frequencies of hundreds of kilohertz have been observed from a ZnO nanobelt under the influence of an alternating electric field. Here, we observe mechanical resonance and radiative emission at ∼ 0.36 THz from core-shell ZnO mesocrystal microspheres excited by a continuous green-wavelength laser. We find that ∼ 0.016% of the incident power is converted into terahertz radiation, which corresponds to a quantum efficiency of ∼ 33%, making the ZnO microspheres competitive with existing terahertz-emitting materials. The mechanical resonance and radiation stem from the coherent photo-induced vibration of the hexagonal ZnO nanoplates that make up the microsphere shells. The ZnO microspheres are formed by means of a nonclassical, self-organized crystallization process, and represent a straightforward route to terahertz radiation at the nanoscale.

Longitudinal optical phonon-plasmon coupling in luminescent 3C-SiC nanocrystal films

Glycerol-passivated 3C-SiC nanocrystal (NC) solid films with tunable blue photoluminescence show abnormal longitudinal optical (LO) phonon behavior. As the NC size increases, the LO phonon intensity increases in the Raman spectra of the solid films and is even larger than that of the transverse optical mode. The Raman spectra cannot be fitted by using only the phonon confinement model. When further considering the coupling between the LO phonon and plasmon induced by the surface deformation potential in the glycerol layer, good agreement is achieved between the experiments and theory. This indicates that the coupled LO phonon-plasmon effect arising from the surface bonding structure plays a crucial role in the modified LO phonon behavior.

Adult hepatic cavernous haemangioma with highly elevated alpha-fetoprotein

A 35-year-old Chinese man presented with dull pain in the right hypochondrial region for the previous 2 months. Laboratory examination revealed that his serum alpha-fetoprotein level was 1890 microg/L (reference range, 0-20 microg/L), and computed tomographic scan showed a hypodense lesion in the left liver lobe. At laparotomy, a dark reddish soft tumour (3.0 x 3.5 cm in diameter) was found in the medial segment of the liver (segment III). The tumour became markedly smaller than that before resection, and a vessel-like structure was found on the cut surface. Intra-operative pathology and postoperative histopathology examinations revealed that the tumour was a cavernous haemangioma of the liver. The serum alpha-fetoprotein level decreased to 3.5 microg/L by the fourth postoperative week. Clinicians should be aware that some rare tumours besides hepatocellular carcinoma and endodermal sinus tumours (yolk sac tumour), for example, hepatic haemangioma, can produce alpha-fetoprotein.

First Report of Root and Stem Rot Caused by Phytophthora nicotianae on Peperomia tetraphylla in China

Peperomia tetraphylla, an evergreen herb, is becoming increasingly popular as a potted ornamental plant in southern China. In the summer of 2008, in some commercial flower nurseries in Shenzhen, Guangdong Province, P. tetraphylla showed extensive black stem and root rot, with leaves dropping from the rotten stem. Small pieces (approximately 3 mm²) of stems and leaves were excised from the margins of the black lesions, surface disinfected for 30 s to 1 min in 0.1% HgCl₂, plated onto potato dextrose agar (PDA), and incubated at 25°C in the dark. All the plated samples yielded Phytophthora, and microscopic examination of pure cultures grown on PDA plates showed arachnoid colonies with abundant aerial mycelium, chlamydospores, and a few sporangia. Numerous sporangia were formed in sterile soil extract. Sporangia were ovoid or obpyriform, noncaducous, with prominent solitary papillae, and measured 31 to 52 μm (average 38 μm) × 21 to 34 μm (average 27 μm). Chlamydospores were spherical and 21 to 34 μm in diameter (average 28 μm). The internal transcribed spacer (ITS) region of rDNA of a single isolate was amplified using primers ITS₄/ITS₅ and sequenced (2). The ITS sequence, when submitted for a BLAST search in the NCBI database, showed 100% homology with the sequences of two reference isolates of Phytophthora nicotianae (Accession Nos. AY833526 and EU433396) and the consensus ITS sequence was deposited in the NCBI as Accession No. GQ499373. The isolate was identified as Phytophthora nicotianae on the basis of morphological and molecular characteristics (1). Pathogenicity of the isolate was confirmed by inoculating 1-year-old plants of P. tetraphylla growing in pots. The isolate was grown for 7 days on PDA plates and mycelial plugs, 5 mm in diameter and taken from the advancing margins of the colonies, were buried approximately 1 cm deep near the base of the stem in such a way that the mycelium on the plugs was in contact with the surface of the stem, which had been wiped earlier with 70% ethanol and gently wounded with a needle. Plants treated the same way but inoculated with sterile PDA plugs served as control plants. Three plants in each pot were inoculated and there were five replications each for the treatment and the control. All plants were kept in a greenhouse at 22 to 32°C. After 6 to 7 days, the inoculated plants showed black lesions around the mycelial plugs; symptoms of root and stem rot developed rapidly thereafter and the plants collapsed within 2 weeks. All symptoms on the inoculated plants were identical to those observed in naturally diseased plants, whereas the control plants remained healthy. The same fungus was consistently reisolated from the inoculated plants. To our knowledge, this is the first report of Phytophthora nicotianae on P. tetraphylla in China. References: (1) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society, St. Paul, MN, 1996. (2) J. B. Ristaino et al. Appl. Environ. Microbiol. 64:948, 1998.

Crystalline core/shell Si/SiO2 nanotubes formed via interfacial stress imbalance

Crystalline core/shell Si/SiO2 nanotubes (NTs) with outer diameters of 130-220 nm and lengths of approximately 1 microm have been synthesized using thermal evaporation. High resolution scanning electron microscopy reveals that the NT formation stems from the intrinsic interfacial stress imbalance in the strained Si/SiO2 bilayered film, consequently leading to NTs with different orifice levels. The NT diameters depend strongly on the bilayer film thicknesses and crystal orientations of the Si and SiO2 layers. A modified Timoshenko formula is derived to calculate the dependence of the tube diameter on the bilayer film thickness. The obtained results are consistent well with experimental data.

Primary solitary fibrous tumor of the vulva: a case report

BACKGROUND

Solitary fibrous tumor (SFT) of the female genital tract is an extremely rare neoplasm of mesenchymal origin.

CASE

A case of primary SFT originated from the vulva of a 39-year-old woman. The tumor presented as a 10-cm, well-circumscribed lump and was composed of bland-looking cells admixed with thin and thick collagen fibers with the appearance of hemangiopericytoma. Immunohistochemically, the spindle cells were strongly positive for CD99 and vimentin, with focal positivity for CD34, and were negative for S100, SMA, desmin, ER, PR, etc. Microscopic evaluation and immunohistochemistry supported the diagnosis of a primary benign vulvar SFT. The patient remained well 10 months after excision.

CONCLUSION

To the best of our knowledge, this report is the first Chinese case of vulvar SFT in the English-language literature. SFT should be taken into consideration during the diagnostic process with spindle cell lesions of the vulva. The outcome of this tumor is based mostly on complete surgical resection.

Tunneling of micron-sized droplets through soap films

When a micron-sized water droplet impacts on a freely suspended soap film with speed v(i), there exists a critical impact velocity of penetration v(C). Droplets with v(i)<v(C) merge and flow with the film after impacts, whereas droplets with v(i)>v(C) tunnel through it. In all cases, the film remains intact despite the fact that the droplet radius (R_{0}=26 μm) is much greater than the film thickness (0<h≲10 μm) . The critical velocity v(C) is measured as a function of h , and interestingly v(C) approaches an asymptotic value v(C0)≃520 cm/s in the limit h→0 . This indicates that in addition to an inertial effect, a deformation or stretching energy of the film is required for penetration. Quantitatively, we found that this deformation energy corresponds to the creation of ∼14 times of the cross-sectional area of the droplet (14πR(0)(2)) or a critical Weber number We(C)}(≡2ρ(w) v(C0)(2) R(0)/σ)≃44 , where ρ(w) and σ are, respectively, the density and the surface tension of water.

Hexagonal Domain-Like Charge Density Wave Phase of TaS2 Determined by Scanning Tunneling Microscopy

The structure of the room-temperature charge density wave (CDW) phase in octahedrally coordinated tantalum disulfide, 1T-TaS2, has been a controversial issue for over 15 years. Large-scale scanning tunneling microscope images of the intralayer structure of this phase exhibit a domain-like pattern defined by a variation in the maximum CDW amplitude. The circular domains, consisting of high-amplitude CDWs, are arranged in a regular hexagonal lattice (period 73+/-3 angstroms) that is rotated relative to the CDWs. In addition, from the analysis of atomic resolution images it was determined that there is a well-defined phase shift between the CDWs in adjacent domains, and that within a domain the CDW superlattice is commensurate with the atomic lattice. These results provide evidence for the hexagonal discommensurate CDW phase in 1T-TaS2 and also suggest an explanation for the long-standing controversy concerning the structure of this phase.

Glycerol-bonded 3C-SiC nanocrystal solid films exhibiting broad and stable violet to blue-green emission

We have produced glycerol-bonded 3C-SiC nanocrystal (NC) films, which when excited by photons of different wavelengths, produce strong and tunable violet to blue-green (360-540 nm) emission as a result of the quantum confinement effects rendered by the 3C-SiC NCs. The emission is so intense that the emission spots are visible to the naked eyes. The light emission is very stable and even after storing in air for more than six months, no intensity degradation can be observed. X-ray photoelectron spectroscopy and absorption fine structure measurements indicate that the Si-terminated NC surfaces are completely bonded to glycerol molecules. Calculations of geometry optimization and electron structures based on the density functional theory for 3C-SiC NCs with attached glycerol molecules show that these molecules are bonded on the NCs causing strong surface structural change, while the isolated levels in the conduction band of the bare 3C-SiC NCs are replaced with quasi-continuous bands that provide continuous tunability of the emitted light by changing the frequencies of exciting laser. As an application, we demonstrate the potential of using 3C-SiC NCs to fabricate full-color emitting solid films by incorporating porous silicon.

Size-independent low-frequency Raman scattering in Ge-nanocrystal-embedded SiO2 films

The peak position and linewidth of the low-frequency Raman mode observed from amorphous silica films embedded with Ge nanocrystals doped with Si show a size-independent behavior. Spectral analysis reveals the formation of a thin amorphous GeSi layer on the surface of the Ge nanocrystal. Theoretical calculation based on a modified three-region model discloses that the acoustic impedance of the interfacial GeSiO layer is responsible for the size-independent behavior. During high-temperature annealing, Ge atoms are segregated from the interface into the core, and the GeSiO interface layer is converted to SiO(2), leading to disappearance of the size-independent vibration mode.

Predictive ability of direct genomic values for lifetime net merit of Holstein sires using selected subsets of single nucleotide polymorphism markers

The objective of the present study was to assess the predictive ability of subsets of single nucleotide polymorphism (SNP) markers for development of low-cost, low-density genotyping assays in dairy cattle. Dense SNP genotypes of 4,703 Holstein bulls were provided by the USDA Agricultural Research Service. A subset of 3,305 bulls born from 1952 to 1998 was used to fit various models (training set), and a subset of 1,398 bulls born from 1999 to 2002 was used to evaluate their predictive ability (testing set). After editing, data included genotypes for 32,518 SNP and August 2003 and April 2008 predicted transmitting abilities (PTA) for lifetime net merit (LNM$), the latter resulting from progeny testing. The Bayesian least absolute shrinkage and selection operator method was used to regress August 2003 PTA on marker covariates in the training set to arrive at estimates of marker effects and direct genomic PTA. The coefficient of determination (R(2)) from regressing the April 2008 progeny test PTA of bulls in the testing set on their August 2003 direct genomic PTA was 0.375. Subsets of 300, 500, 750, 1,000, 1,250, 1,500, and 2,000 SNP were created by choosing equally spaced and highly ranked SNP, with the latter based on the absolute value of their estimated effects obtained from the training set. The SNP effects were re-estimated from the training set for each subset of SNP, and the 2008 progeny test PTA of bulls in the testing set were regressed on corresponding direct genomic PTA. The R(2) values for subsets of 300, 500, 750, 1,000, 1,250, 1,500, and 2,000 SNP with largest effects (evenly spaced SNP) were 0.184 (0.064), 0.236 (0.111), 0.269 (0.190), 0.289 (0.179), 0.307 (0.228), 0.313 (0.268), and 0.322 (0.291), respectively. These results indicate that a low-density assay comprising selected SNP could be a cost-effective alternative for selection decisions and that significant gains in predictive ability may be achieved by increasing the number of SNP allocated to such an assay from 300 or fewer to 1,000 or more.

Identification of surface structures on 3C-SiC nanocrystals with hydrogen and hydroxyl bonding by photoluminescence

SiC nanocrystals (NCs) exhibit unique surface chemistry and possess special properties. This provides the opportunity to design suitable surface structures by terminating the surface dangling bonds with different atoms thereby boding well for practical applications. In this article, we report the photoluminescence properties of 3C-SiC NCs in water suspensions with different pH values. Besides a blue band stemming from the quantum confinement effect, the 3C-SiC NCs show an additional photoluminescence band at 510 nm when the excitation wavelengths are longer than 350 nm. Its intensity relative to the blue band increases with the excitation wavelength. The 510 nm band appears only in acidic suspensions but not in alkaline ones. Fourier transform infrared, X-ray photoelectron spectroscopy, and X-ray absorption near-edge structure analyses clearly reveal that the 3C-SiC NCs in the water suspension have Si-H and Si-OH bonds on their surface, implying that water molecules only react with a Si-terminated surface. First-principle calculations suggest that the additional 510 nm band arises from structures induced by H(+) and OH(-) dissociated from water and attached to Si dimers on the modified (001) Si-terminated portion of the NCs. The size requirement is consistent with the observation that the 510 nm band can only be observed when the excitation wavelengths are relatively large, that is, excitation of bigger NCs.

Strong strain hardening in nanocrystalline nickel

Low strain hardening has hitherto been considered an intrinsic behavior for most nanocrystalline (NC) metals, due to their perceived inability to accumulate dislocations. In this Letter, we show strong strain hardening in NC nickel with a grain size of approximately 20 nm under large plastic strains. Contrary to common belief, we have observed significant dislocation accumulation in the grain interior. This is enabled primarily by Lomer-Cottrell locks, which pin the lock-forming dislocations and obstruct dislocation motion. These observations may help with developing strong and ductile NC metals and alloys.

Syntheses and growth mechanisms of 3C-SiC nanostructures from carbon and silicon powders

Cubic silicon carbide (3C-SiC) nanostructures such as needle- and Y-shaped nanowhiskers, smooth and pagoda-shaped nanorods are synthesized on a large scale from activated carbon and silicon powders at 1250 degrees C under atmospheric pressure. The use of ball-milled silicon powders results in the formation of nanowires and nanowhiskers, whereas non-milled silicon powders lead to nanorods together with unreacted silicon powders. Residual oxygen in the growth chamber initiates the carburization reactions which can proceed without further oxygen consumption. The size and morphology of the as-synthesized 3C-SiC nanostructures are observed to be related to the size and morphology of the starting silicon particles. An oxygen-assisted gas-solid model is proposed to explain the observed nanostructures.

Synthesis and characteristics of cubic silicon carbide nanospheres with smooth surfaces

Large quantities of cubic silicon carbide (3C-SiC) nanospheres are synthesized on silicon wafer using zinc sulphide (ZnS) and activated carbon powder. The synthesized nanospheres have smooth surfaces and their diameters range from 20 to 430 nm. The growth of these nanospheres can be explained by a gas-solid model. ZnS powder plays a key role in the formation of activated Si and SiOx. Carburization of the activated Si and SiOx by CO gas leads to the formation of the 3C-SiC nanospheres. Special three-dimensional structure of the product is related to high concentrations of the reactants.

Tin oxide nanoribbons with vacancy structures in luminescence-sensitive oxygen sensing

Vacancy structures in tin oxide nanoribbons fabricated via thermal evaporation and post-processing are probed by luminescence spectroscopy, and interesting properties that bode well for oxygen sensing are observed. Besides a broad 620-nm band, the fabricated tin oxide nanoribbons show a photoluminescence band at 480 nm when the measurement temperature is <100 K. The blue band appears from nanoribbons synthesized under high oxygen pressure or annealed under oxygen. The dependence suggests that the oxygen interstitial and vacancy densities determine the electronic states that produce the blue band. Calculation of the electron structures based on the density functional theory shows that decreased oxygen vacancies or increased oxygen interstitials enhance the 480-nm band but suppress the 620-nm band. The results reported here indicate that the tin oxide nanoribbons with vacancy structures have potential applications in luminescence-sensitive oxygen sensing.

Persistent skewness of a strongly active scalar

We present a skewness measurement of the density fluctuations deltarho[over ]_{l} on scales l in a vertical turbulent soap film driven by a temperature gradient. Unlike the temperature difference deltaT_{l} in Rayleigh-Bénard convection, the density difference in the film is strongly active because deltarho[over ]_{l}/rho[over ]>>deltaT_{l}T[over ] , where the over-bar indicates the mean. Our results show persistent nonzero skewness S_{y}(l) identical with <deltarho[over ]_{l};{3}>/<deltarho[over ]_{l};{2};{3/2}> on different scales along the gravity direction y[over ]; S_{y}(l) is positive for small l and negative for large l. The sign switch occurs approximately at the Bolgiano length scale l_{B}. The simultaneous presence of positive and negative skewnesses is interpreted here as a result of the structures of rising and falling plumes in a strongly stratified medium.

[Establishment of a B16 cell line stably expressing genes encoding HER2 multi-epitope peptides in vivo]

AIM

To establish a B16 cell line stably expressing genes encoding HER2 multi-epitope peptides in vivo.

METHODS

Eukaryotic expressing vector pcDNA3-GFP-HER2 was constructed by molecular cloning technique and transfected into B16 cells mediated by cationic liposome. After screened with G418, the transfected cells were passaged in vivo. The GFP-HER2 positive cells were isolated from tumor burdening mice by flow cytometry (FCM) sorting, and then monoclonized in the absence of G418 to obtain a B16 cell line stably expressing genes encoding HER2 multi-epitope peptides in vivo. This cell line was then identified after being passaged in vivo.

RESULTS

Restriction endonulease analysis and DNA sequencing showed that the pcDNA3-GFP-HER2 was constructed and a B16 cell line stably expressing genes encoding HER2 multi-epitope peptides in vivo was obtained successfully. The GFP-HER2 positive proportion maintained higher than 90% after being passaged in vivo.

CONCLUSION

A B16 cell line stably expressing genes encoding HER2 multi-epitope peptides is established successfully, which would provide a method to establish other cell lines stably expressing exogenous genes.