Molecular evolution and gene expression of ferritin family involved in immune defense of lampreys.

Ferritin, one of the key regulators of iron homeostasis, is widely present throughout almost all species. The vertebrate ferritin family, which originates from a single gene in the ancestral invertebrates, contains the widest variety of ferritin subtypes among all animal species. However, the evolutionary history of the vertebrate ferritin family remains to be further clarified. In this study, genome-wide identification of the ferritin homologs is performed in lampreys, which are the extant representatives of jawless vertebrates that diverged from the future jawed vertebrates more than 500 million years ago. Molecular evolutionary analyses show that four members of the lamprey ferritin family, L-FT1-4, are derived from a common ancestor with jawed vertebrate ferritins prior to the divergence of the jawed vertebrate ferritin subtypes. The lamprey ferritin family shares evolutionarily conserved characteristics of the ferritin H subunit with higher vertebrates, but certain members such as L-FT1 additionally accumulate some features of the M or L subunits. Expression profiling reveals that lamprey ferritins are highly expressed in the liver. The transcription of L-FT1 is significantly induced in the liver and heart during lipopolysaccharide stimulation, indicating that L-FTs may play a role in the innate immune response to bacterial infection in lampreys. Furthermore, the transcriptional expression of L-FT1 in quiescent and LPS-activated leukocytes is up- and down-regulated by the lamprey TGF-ß2, an essential regulator of the inflammatory response, respectively. Our results provide new insights into the origin and evolution of the vertebrate ferritin family and reveal that lamprey ferritins may be involved in immune regulation as target genes of the TGF-ß signaling pathway.

Spatial-ID: a cell typing method for spatially resolved transcriptomics via transfer learning and spatial embedding.

Spatially resolved transcriptomics provides the opportunity to investigate the gene expression profiles and the spatial context of cells in naive state, but at low transcript detection sensitivity or with limited gene throughput. Comprehensive annotating of cell types in spatially resolved transcriptomics to understand biological processes at the single cell level remains challenging. Here we propose Spatial-ID, a supervision-based cell typing method, that combines the existing knowledge of reference single-cell RNA-seq data and the spatial information of spatially resolved transcriptomics data. We present a series of benchmarking analyses on publicly available spatially resolved transcriptomics datasets, that demonstrate the superiority of Spatial-ID compared with state-of-the-art methods. Besides, we apply Spatial-ID on a self-collected mouse brain hemisphere dataset measured by Stereo-seq, that shows the scalability of Spatial-ID to three-dimensional large field tissues with subcellular spatial resolution.

Antitumor Effect of Si-Jun-Zi Decoction on SGC7901 Gastric Cancer Cells by CMTM2 Activation.

The Si-Jun-Zi decoction (SJZ), a traditional Chinese medicine (TCM) formula, is used clinically against multiple malignancies, including gastric cancer (GC). In previous study, we have shown that SJZ plays an anticancer role in SGC7901 cell xenograft mice models. However, the underlying mechanisms are unclear. The objective of this study was to evaluate the effect and mechanism of SJZ on the proliferation, migration, invasion, and cancer stem cell-like properties of GC cells. High-throughput mRNA sequencing analysis was performed to investigate the global alterations in gene expression in xenograft tumors, and 56 significantly differentially expressed genes (43 upregulated and 13 downregulated genes) were identified between the SJZ group and the Model group totally. We focused on CMTM2, which was significantly increased after SJZ intervention, as a candidate target gene of SJZ. The results indicated that CMTM2 expression was elevated in SJZ-treated SGC7901 cells and knocking-down CMTM2 expression partially hampered the inhibitory effects of SJZ on the proliferation, migration, and invasion of GC cells. Moreover, SJZ treatment repressed the spheroid and colony-forming capacity in GC cells, accompanied by downregulation of stem cell markers including SOX2, NANOG, and CD44. CMTM2 knockdown antagonized the effects of SJZ on the cancer stem cell-like properties of SGC7901 cells. Thus, SJZ effectively suppressed the proliferation, migration, invasion, and cancer stem cell-like properties of GC cells in vitro by upregulating CMTM2 expression.

High-resolution 3D spatiotemporal transcriptomic maps of developing Drosophila embryos and larvae.

Drosophila has long been a successful model organism in multiple biomedical fields. Spatial gene expression patterns are critical for the understanding of complex pathways and interactions, whereas temporal gene expression changes are vital for studying highly dynamic physiological activities. Systematic studies in Drosophila are still impeded by the lack of spatiotemporal transcriptomic information. Here, utilizing spatial enhanced resolution omics-sequencing (Stereo-seq), we dissected the spatiotemporal transcriptomic changes of developing Drosophila with high resolution and sensitivity. We demonstrated that Stereo-seq data can be used for the 3D reconstruction of the spatial transcriptomes of Drosophila embryos and larvae. With these 3D models, we identified functional subregions in embryonic and larval midguts, uncovered spatial cell state dynamics of larval testis, and revealed known and potential regulons of transcription factors within their topographic background. Our data provide the Drosophila research community with useful resources of organism-wide spatiotemporally resolved transcriptomic information across developmental stages.

Molecular Evolution of Transforming Growth Factor-ß (TGF-ß) Gene Family and the Functional Characterization of Lamprey TGF-ß2.

The transforming growth factor-ßs (TGF-ßs) are multifunctional cytokines capable of regulating a wide range of cellular behaviors and play a key role in maintaining the homeostasis of the immune system. The TGF-ß subfamily, which is only present in deuterostomes, expands from a single gene in invertebrates to multiple members in jawed vertebrates. However, the evolutionary processes of the TGF-ß subfamily in vertebrates still lack sufficient elucidation. In this study, the TGF-ß homologs are identified at the genome-wide level in the reissner lamprey (Lethenteron reissneri), the sea lamprey (Petromyzon marinus), and the Japanese lamprey (Lampetra japonica), which are the extant representatives of jawless vertebrates with a history of more than 350 million years. The molecular evolutionary analyses reveal that the lamprey TGF-ß subfamily contains two members representing ancestors of TGF-ß2 and 3 in vertebrates, respectively, but TGF-ß1 is absent. The transcriptional expression patterns show that the lamprey TGF-ß2 may play a central regulatory role in the innate immune response of the lamprey since it exhibits a more rapid and significant upregulation of expression than TGF-ß3 during lipopolysaccharide stimuli. The incorporation of BrdU assay reveals that the lamprey TGF-ß2 recombinant protein exerts the bipolar regulation on the proliferation of the supraneural myeloid body cells (SMB cells) in the quiescent and LPS-activated state, while plays an inhibitory role in the proliferation of quiescent and activated leukocytes in lampreys. Furthermore, caspase-3/7 activity analysis indicates that the lamprey TGF-ß2 protects SMB cells from apoptosis after serum deprivation, in contrast to promoting apoptosis of leukocytes. Our composite results offer valuable clues to the origin and evolution of the TGF-ß subfamily and imply that TGF-ßs are among the most ancestral immune regulators in vertebrates.

High-Throughput Sequencing Reveals the Differential MicroRNA Expression Profiles of Human Gastric Cancer SGC7901 Cell Xenograft Nude Mouse Models Treated with Traditional Chinese Medicine Si Jun Zi Tang Decoction.

Objective. The present study aimed to investigate the potential mechanism underlying the antitumor effect of Si Jun Zi Tang (SJZT) decoction on gastric cancer. Methods. Twelve human gastric cancer SGC7901 cell xenograft nude mouse models were established. The mice were randomly divided into the Model group and SJZT group. SJZT exerted significant antitumor effects after 21 days of decoction administration. High-throughput sequencing was used to analyze the microRNA (miRNA) expression profiles of tumor tissues. Bioinformatics analysis was performed to provide further information regarding the differentially expressed miRNAs. Five representative differentially expressed miRNAs and four predicted target genes were further validated using quantitative real-time reverse transcription PCR (qRT-PCR). Results. We identified 33 miRNAs that were differentially expressed in the SJZT group compared with the Model group. Among them, 32 miRNAs were upregulated and 1 miRNA was downregulated. Bioinformatic analysis showed that most of miRNAs acted as tumor suppressors and their target genes participated in multiple signaling pathways, including the PI3K/Akt signaling pathway, microRNAs in cancer, and Wnt signaling pathway. The qRT-PCR result confirmed that miR-223-3p, miR-205-5p, miR-147b-3p, and miR-223-5p were overexpressed and their respective paired target genes FUT9, POU2F1, MUC4, and RAB14 mRNA were obviously downregulated in the SJZT group compared with those in the Model group. Network analysis revealed that miR-223-3p and miR-205-5p shared two targets POU2F1 (encoding POU class 2 homeobox 1) and FUT9 (encoding fucosyltransferase 9), suggesting they have a common role in certain pathways. Conclusion. This study provided novel insights into the anticancer mechanism of SJZT against gastric cancer, which might be partly related to the modulation of miRNA expression and their target pathways in tumors.

[Mechanism of puerarin reversing SH-SY5Y cell injury induced by Aß_(1-42) based on proteomics].

Puerarin has the anti-Alzheimer's disease (AD) activity,which can reverse nerve injury induced by Aßand inhibit neuronal apoptosis.However,its potential pharmacodynamic mechanism still needs to be further researched.The occurrence and development of AD is due to the change of multiple metabolic links in the body,which leads to the destruction of balance.Puerarin may act on multiple targets and multiple metabolic processes to achieve therapeutic purposes.Quantitative proteomic analysis provides a new choice to understand the mechanism as completely as possible.This research adopted SH-SY5Y cells induced by Aß_(1-42)to establish AD cell model,and Aßimmunofluorescence detection showed that Aßdecreased significantly after puerarin intervention.The mechanism of puerarin reversing SH-SY5Y cell injured by Aß_(1-42)was further explored by using label-free non-labeled quantitative technology and Western blot detection based on bioinformatics analysis result.The results showed that most of the differential proteins were related to biological processes such as cellular component organization or biogenesis,cellular component organization and cellular component biogenesis,and they mainly participated in the top ten pathways of P value such as pathogenic Escherichia coli infection,m TOR signaling pathway,regulation of autophagy,regulation of actin cytoskeleton,spliceosome,hepatocellular carcinoma,tight junction,non-small cell lung cancer,apoptosis and gap junction.Annexin V/PI flow cytometry and TUNEL were used to detect apoptosis,and the results showed that Aßdecreased significantly and the rate of apoptosis decreased significantly after puerarin intervention.Western blot analysis found that the protein expression level of autophagy related protein LC3Ⅱwas up-regulated after Aßinduction,and the degree of this up-regulation was further enhanced in puerarin intervention group.The trend of the ratio of LC3Ⅱ/LC3Ⅰamong groups was the same as the protein expression level of LC3Ⅱ，the protein expression level of p62 in the control group,AD model group and puerarin intervention group decreased successively.Protein interaction network analysis showed that CAP1 was correlated with TUBA1B,HSP90AB2P,DNM1L,TUBA1A and ERK1/2,and the correlation between CAP1 and ERK1/2 was the highest among them.Western blot showed that the expressions of p-ERK1/2,Bax and CAP1 were significantly down-regulated and the protein expression level of Bcl-2 was significantly up-regulated after puerarin intervention.Therefore,puerarin might improve the SH-SY5Y cells injured by Aß_(1-42)through the interaction of multiple biological processes and pathways in cells multiple locations,and CAP1 might play an important role among them.

stLFRsv: A Germline Structural Variant Analysis Pipeline Using Co-barcoded Reads.

Co-barcoded reads originating from long DNA fragments (mean length >30 kbp) maintain both single base level accuracy and long-range genomic information. We propose a pipeline, stLFRsv, to detect structural variation using co-barcoded reads. stLFRsv identifies abnormal large gaps between co-barcoded reads to detect potential breakpoints and reconstruct complex structural variants (SVs). Haplotype phasing by co-barcoded reads increases the signal to noise ratio, and barcode sharing profiles are used to filter out false positives. We integrate the short read SV caller smoove for smaller variants with stLFRsv. The integrated pipeline was evaluated on the well-characterized genome HG002/NA24385, and 74.5% precision and a 22.4% recall rate were obtained for deletions. stLFRsv revealed some large variants not included in the benchmark set that were verified by long reads or assembly. For the HG001/NA12878 genome, stLFRsv also achieved the best performance for both resource usage and the detection of large variants. Our work indicates that co-barcoded read technology has the potential to improve genome completeness.

Tanshinone IIA protects mice against atherosclerotic injury by activating the TGF-ß/PI3K/Akt/eNOS pathway.

OBJECTIVE: Explored the mechanism of action of tanshinone IIA (TIIA) against atherosclerosis. METHODS: ApoE mice were divided into two groups of 10: model and TIIA. A control group of 10 wild-type mice was created. ApoE mice were fed a high-fat diet for 12 weeks. The TIIA group received TIIA once daily. Mice were anesthetized, blood collected by cardiac puncture, and the aortic sinus/arch collected for histology and molecular studies, respectively. RESULTS: Mice intima in the model group had large areas of plaque formation, serum levels of total cholesterol (TC), triglycerides, and low-density lipoprotein-cholesterol (LDL-C) increased significantly, and high-density lipoprotein-cholesterol (HDL-C) levels decreased significantly in the model group after 12 weeks. Staining [hematoxylin and eosin (H&E), Oil-Red-O] showed that the aorta had lesions, a higher degree of plaque formation, and considerable lipid deposition in model-group mice. After TIIA treatment, expression of HDL-C was increased significantly and that of TC, triglycerides and LDL-C decreased significantly, and plaque size and lipid deposition improved obviously. Analyses of protein phosphorylation in aortic tissue suggested that the transforming growth factor (TGF)-ß/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/endothelial nitric oxide synthase (eNOS) pathway was activated in TIIA-treated mice. CONCLUSION: TIIA can lower levels of serum lipids, stabilize atherosclerotic plaques, reduce endothelial injury, and inflammatory damage by activation of the TGF-ß/PI3K/Akt/eNOS pathway.

IL-1ß promotes the nuclear translocaiton of S100A4 protein in gastric cancer cells MGC803 and the cell's stem-like properties through PI3K pathway.

It has been shown that nuclear expression of S100A4 is significantly correlated with increased metastasis and reduced survival in patients with gastric cancer and many other cancers. However, the factors which could influence the nuclear contents of S100A4 in cancer cells are not clear. It has also been reported that Interleukin-1ß (IL-1ß) promotes the nuclear translocation of S100A4 in chondrocytes. Previous studies have shown that IL-1ß promotes the stemness of colon cancer cells, and S100A4 is also involved in maintaining cancer-initiating cells in head and neck cancers. We speculate that IL-1ß might promote the nuclear translocation of S100A4 protein in MGC803 gastric cancer cells and therefore enhance their stem-like properties. The results from Western-blot and qRT-PCR analysis showed that IL-1ß increased the nuclear and total cellular content of S100A4 protein and S100A4 mRNA level in MGC803 cells. LY294002, a pharmacological inhibitor of Phosphoinositide 3-kinase (PI3K) reversed the above effects. Functional studies indicated that IL-1ß promoted the colony-forming and spheroid-forming capabilities of the cells and the expression of SOX2 and NANOG gene. PI3K or S100A4 inhibition reversed the IL-1ß-mediated increase in colony and spheroid-forming capabilities of the cells. LY294002 also reversed the elevated SOX2 and NANOG expression induced by IL-1ß. Our study demonstrated that IL-1ß promote the nuclear translocation of S100A4 protein in gastric cancer cells MGC803, which are PI3K dependent, suggesting the existence of IL-1ß-PI3K-S100A4 pathway for the first time. The study also showed that IL-1ß promoted stem-like properties of the cells through the new pathway.

miR-3189-3p Mimics Enhance the Effects of S100A4 siRNA on the Inhibition of Proliferation and Migration of Gastric Cancer Cells by Targeting CFL2.

GDF15 is a downstream gene of S100A4. miR-3189 is embedded in the intron of GDF15-and coexpressed with it. miR-3189-3p functions to inhibit the proliferation and migration of glioblastoma cells. We speculated that S100A4 might regulate miR-3189-3p to affect its function in gastric cancer cells. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) showed that miR-3189-3p expression was significantly downregulated in MGC803 cells after S100A4 knockdown. Overexpression of miR-3189-3p significantly inhibited the proliferation and migration of the cells. Moreover, miR-3189-3p mimics enhanced the effects of an S100A4 siRNA on the inhibition of cell proliferation and migration. Dual luciferase reporter assays, qRT-PCR, and Western blotting verified that CFL2 is a direct target of miR-3189-3p. CFL2 mediates the regulation of miR-3189-3p on the proliferation and migration of MGC803 cells. Data mining based on Kaplan-Meier plots showed that high CFL2 expression is associated with poor overall survival and first progression in gastric cancer. These data suggested that miR-3189-3p mimics enhanced the effects of the S100A4 siRNA on the inhibition of gastric cancer cell proliferation and migration by targeting CFL2. The findings suggested that when targeting S100A4 to treat gastric cancer, consideration and correction for counteracting factors should obtain a satisfactory effect.

Effects of nuclear factor 5 of activated T cells on proliferation and apoptosis of human gastric cancer MGC803 cells / 中国肿瘤生物治疗杂志

@#Objective: To investigate the effects of nuclear factor 5 of activated T cells (NFAT5) on proliferation and apoptosis of human gastric cancer MGC803 cells and to explore the possible mechanisms. Methods: Three siRNAs targeting NFAT5 gene (siRNA2567, siRNA2714 and siRNA4562) and one negative control siRNA were designed and chemically synthesized before transfected into human gastric cancer cell line MGC803 by liposome. Real-time PCR was used to detect the changes of N F AT 5 mRNA expression in MGC803 cells to further pick out the siRNA that most effectively inhibit the expression of N F AT 5 . Further, Real-time PCR and Western blotting assay were carried out to test mRNAand protein levels of NFAT5 and S100A4 in cells 48 h after N F AT 5 -siRNAtransfection. Then, CCK-8 assay and FCM assay were used to detect the influence of silencing N F AT 5 on cell proliferation and apoptosis, respectively. Results: siRNA2567 was the most effective siRNA that significantly inhibited the expression of N F AT 5 mRNA ( P <0.01), and thus was validated as NFAT5-siRNA. Real-time PCR and Western blotting assay confirmed that both mRNA and protein levels of NFAT5 and S100A4 were down-regulated in cells 48 h after N F AT 5 -siRNAtransfection. Compared with NC-siRNAgroup, the proliferation ability of MGC803 cells in the N F AT 5 siRNAgroup was significantly down-regulated at 72 h and 96 h ( P <0.01).And FCM assay showed that compared with NC-siRNA group, cell apoptosis rate of N F AT 5 -siRNA group was significantly increased from (2.7±0.2)% to (7.9±0.2)%, ( P <0.01) 48 h after N F AT 5 -siRNA transfection. Conclusion: N F AT 5 -siRNA transfection can silence N F AT 5 gene expression in gastric cancer MGC803 cells effectively. N F AT 5 may inhibit proliferation and promote cell apoptosis of gastric cancer cells possibly through regulating S100A4 expression.

Rapid Targeted Next-Generation Sequencing Platform for Molecular Screening and Clinical Genotyping in Subjects with Hemoglobinopathies.

Hemoglobinopathies are among the most common autosomal-recessive disorders worldwide. A comprehensive next-generation sequencing (NGS) test would greatly facilitate screening and diagnosis of these disorders. An NGS panel targeting the coding regions of hemoglobin genes and four modifier genes was designed. We validated the assay by using 2522 subjects affected with hemoglobinopathies and applied it to carrier testing in a cohort of 10,111 couples who were also screened through traditional methods. In the clinical genotyping analysis of 1182 ß-thalassemia subjects, we identified a group of additional variants that can be used for accurate diagnosis. In the molecular screening analysis of the 10,111 couples, we detected 4180 individuals in total who carried 4840 mutant alleles, and identified 186 couples at risk of having affected offspring. 12.1% of the pathogenic or likely pathogenic variants identified by our NGS assay, which were undetectable by traditional methods. Compared with the traditional methods, our assay identified an additional at-risk 35 couples. We describe a comprehensive NGS-based test that offers advantages over the traditional screening/molecular testing methods. To our knowledge, this is among the first large-scale population study to systematically evaluate the application of an NGS technique in carrier screening and molecular diagnosis of hemoglobinopathies.

FAM107B is regulated by S100A4 and mediates the effect of S100A4 on the proliferation and migration of MGC803 gastric cancer cells.

FAM107B expression was decreased in stomach cancer and many other kinds of cancer. The forced expression of FAM107B in HeLa cells diminished proliferation in response to growth factors, suggesting that FAM107B might play important roles in many types of cancers. But the mechanisms underlying the decreased expression of FAM107B in cancers are not clear, the functional significance needs to be further clarified. Our previous findings from cDNA microarray showed that there are 179 differentially expressed genes after S100A4 inhibition in gastric cancer cells MGC803. FAM107B was an upregulated one among them. In the present study, we confirmed that FAM107B expression was upregulated in MGC803 cells after S100A4 inhibition by qRT-PCR. We demonstrated for the first time that FAM107B was downregulated by S100A4. The results from CCK-8 and transwell assay showed that FAM107B inhibition by siRNA led to significantly increased proliferation and migrating abilities of MGC803 cells, respectively, indicating that FAM107B plays important roles in inhibiting the proliferation and migration of MGC803 cells. The rescue experiment showed that FAM107B-siRNA transfection reversed the reduced proliferation and migration abilities induced by S100A4 inhibition in the cells. These findings suggest that, as a downstream effector, FAM107B at least partly mediates the effect of S100A4 on the proliferation and migration of MGC803 cells. In conclusion, we first provide experimental evidence suggesting that FAM107B was downregulated by S100A4 in gastric cancer MGC803 cells. And FAM107B at least partially mediates the biological effect of S100A4 in the cells.

Next-generation sequencing improves thalassemia carrier screening among premarital adults in a high prevalence population: the Dai nationality, China.

PURPOSE: Thalassemia is one of the most common monogenic diseases in southwestern China, especially among the Dai ethnic group. Here, we explore the feasibility of a next-generation sequencing (NGS) screening method specifically for the Dai people. METHODS: Blood samples were obtained from Dai people for premarital screening. Double-blind, parallel hemoglobinopathy screening was conducted using both traditional hematological methods (red cell indexes and hemoglobin electrophoresis, then DNA sequencing) and an NGS approach. RESULTS: Among 951 tested individuals, we found a thalassemia carrier rate of 49.5% (471/951) using the NGS screen, in contrast to 22.0% (209/951) found using traditional methods. Almost 74.8% (217/290) of α-thalassemia carriers and 30.5% (25/82) of composite α- and ß-thalassemia carriers were missed by traditional screens. The proportion of such α- and ß-thalassemia carriers among the Dai people is 8.6% (82/951). For ß-thalassemia carriers, the high ratio (66/99) of CD26 mutations may suggest a correlation between CD26 and the environmental adaption of the Dai people. CONCLUSIONS: Methodological comparisons demonstrate the superiority of NGS for both sensitivity and specificity, provide a comprehensive assessment of thalassemia screening strategies, and indicate that NGS is a competitive screening method, especially among populations with a high prevalence of disease.Genet Med advance online publication 26 January 2017.

S100A4 influences cancer stem cell-like properties of MGC803 gastric cancer cells by regulating GDF15 expression.

Many studies have revealed that S100A4 is involved in cancer progression by affecting a variety of biological functions. Our previous study showed that S100A4 influences many biological properties of gastric cancer cells; however, the underlying mechanisms are far from clear. In this study, we used cDNA microarray analysis to investigate the global alterations in gene expression in MGC803 gastric cancer cells after siRNA-mediated S100A4 inhibition. Among the total genes investigated, 179 differentially expressed genes (38 upregulated and 141 downregulated) were detected in S100A4-siRNA transfected MGC803 cells compared with NC-siRNA transfected cells. We focused on the GDF15 gene, which was significantly downregulated after S100A4 inhibition. ChIP studies showed that the S100A4 protein binds to the GDF15 promoter, implicating S100A4 in GDF15 regulation at the transcriptional level. GDF15 overexpression promoted CSC-like properties of MGC803 cells, such as spheroid and soft-agar colony forming abilities. S100A4 inhibition suppressed the CSC-like properties of the cells, whereas, GV141-GDF15 vector transfection reversed these effects. Our results suggest that S100A4 influences the CSC-like properties of MGC803 gastric cancer cells by regulating GDF15 expression.

Cytotoxic effects of tebufenozide in vitro bioassays.

Tebufenozide is considered an environmentally friendly pesticide due to its specificity on target insects, but the effects on human are well studied. Studies on the toxicity of tebufenozide at molecular and cellular level is poorly understood. The present study reveals non-selective cytotoxic effects of tebufenozide, and the apoptotic mechanism induced by tebufenozide on HeLa and Tn5B1-4 cells. We demonstrate that the viability of HeLa and Tn5B1-4 cells is inhibited by tebufenozide in a time- and concentration-dependent manner. Intracellular biochemical assays showed that tebufenozide-induced apoptosis of two cell lines concurrent with a decrease in the mitochondrial membrane potential and an increase reactive oxygen species generation, the release of cytochrome-c into the cytosol and a marked activation of caspase-3. These results indicate that a mitochondrial-dependent intrinsic pathway contributes to tebufenozide induced apoptosis in HeLa and Tn5B1-4 cells and suggests potential threats to ecosystems and human health.

Field and long-term demonstration of a wide area quantum key distribution network.

A wide area quantum key distribution (QKD) network deployed on communication infrastructures provided by China Mobile Ltd. is demonstrated. Three cities and two metropolitan area QKD networks were linked up to form the Hefei-Chaohu-Wuhu wide area QKD network with over 150 kilometers coverage area, in which Hefei metropolitan area QKD network was a typical full-mesh core network to offer all-to-all interconnections, and Wuhu metropolitan area QKD network was a representative quantum access network with point-to-multipoint configuration. The whole wide area QKD network ran for more than 5000 hours, from 21 December 2011 to 19 July 2012, and part of the network stopped until last December. To adapt to the complex and volatile field environment, the Faraday-Michelson QKD system with several stability measures was adopted when we designed QKD devices. Through standardized design of QKD devices, resolution of symmetry problem of QKD devices, and seamless switching in dynamic QKD network, we realized the effective integration between point-to-point QKD techniques and networking schemes.

2 GHz clock quantum key distribution over 260 km of standard telecom fiber.

We report a demonstration of quantum key distribution (QKD) over a standard telecom fiber exceeding 50 dB in loss and 250 km in length. The differential phase shift QKD protocol was chosen and implemented with a 2 GHz system clock rate. By careful optimization of the 1 bit delayed Faraday-Michelson interferometer and the use of the superconducting single photon detector (SSPD), we achieved a quantum bit error rate below 2% when the fiber length was no more than 205 km, and of 3.45% for a 260 km fiber with 52.9 dB loss. We also improved the quantum efficiency of SSPD to obtain a high key rate for 50 km length.