Marinobacter panjinensis sp. nov., a moderately halophilic bacterium isolated from sea tidal flat environment.

Two moderately halotolerant bacterium strains, designated PJ-16T and PJ-38, were isolated from a tidal flat of the red beach in Panjin City, Liaoning Province, PR China. Cells were found to be Gram-stain-negative, aerobic, motile, rod-shaped with a single polar flagellum. Optimum growth of strain PJ-16T occurred at 30 °C, pH 7.0 and 0.2-8.0  % (w/v) NaCl, and strain PJ-38 at 30 °C, pH 6.0-7.0 and 0.2-8.0  % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain PJ-16T was most closely related to Marinobacter denitrificans KCTC 62941T (99.2 % 16S rRNA gene sequence similarity), Marinobacter algicola DSM 16394T (98.6 %), Marinobacter salarius JCM 19399T (98.4 %) and Marinobacter confluentis KCTC 42705T (98.2 %), and strain PJ-38 was most closely related to M. denitrificans KCTC 62941T (99.1 %), M. algicola DSM 16394T (98.6 %), M. salarius JCM 19399T (98.4 %) and M. confluentis KCTC 42705T (98.1 %). The G+C content of the genomic DNA of strain PJ-16T based on its draft genomic sequence was 57.4 mol%. The major cellular fatty acids of strain PJ-16T were C16 : 0, C16 : 1 ω7c/C16 : 1 ω6c and C18 : 1 ω9c. The major respiratory quinone of PJ-16T was ubiquinone-9 and the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The results of the phenotypic, phylogenetic and genomic analyses revealed that strains PJ-16T and PJ-38 represent a novel species of the genus Marinobacter, and the name Marinobacter panjinensis sp. nov. is proposed. The type strain is PJ-16T (= CGMCC 1.13694T= KCTC 72023T).

[Characteristic fingerprint and multi-components quantitative determination for Fuke Qianjin Capsules by HPLC].

To establish an HPLC characteristic fingerprint method of Fuke Qianjin Capsules,and determine the contents of its main components. The analysis was carried out on a Kromasil 100-5-C18 analytical column(4. 6 mm ×250 mm,5 µm) with gradient elution by acetonitrile(A)-0. 1% phosphoric acid aqueous solution(B),a flow rate at 1. 0 m L·min-1 and the detection wavelength of 254 nm.The column temperature was 30 ℃,and the injection volume was 10 µL. The determination method of genistin,jatrorrhizine,andrographolide and 14-deoxy-11,12-didehydroandrographolide index components were studied methodologically. The common mode of the characteristic fingerprint of Fuke Qianjin Capsules was set up with 8 common peaks,which were identified as genistin,jatrorrhizine,palmatine,berberine,andrographolide,14-deoxy-11,12-didehydroandrographolide,Z-ligustilide,and Z-3-butylidenephthalide,respectively,in comparison with the references. The similarities of 20 batches of Fuke Qianjin Capsules samples were above 0. 95. All of the above-mentioned 4 analytes could be well separated under the optimized chromatographic conditions. RSD of precision and repeatability experiment were both less than 1. 5%,and the sample solution was stable during 72 h. All of the compounds had a good linearity and linear range. The contents of genistin,jatrorrhizine,andrographolide,and 14-deoxy-11,12-didehydroandrographolide in 20 batches of Fuke Qianjin Capsules samples were 28. 66-56. 04,94. 77-197. 92,1 705. 33-4 148. 93 and 462. 16-1 225. 96 µg in each capsule,respectively. The developed HPLC characteristic fingerprint and quantitative analysis methods were reliable,accurate and sensitive,and could be used effectively evaluate the quality of Fuke Qianjin Capsules samples.

Dietary Total Prenylflavonoids from the Fruits of Psoralea corylifolia L. Prevents Age-Related Cognitive Deficits and Down-Regulates Alzheimer's Markers in SAMP8 Mice.

Alzheimer's disease (AD) is a serious threat for the aging society. In this study, we examined the preventive effect of the total prenylflavonoids (TPFB) prepared from the dried fruits of Psoralea corylifolia L., using an age-related AD mouse model SAMP8. We found that long-term dietary TPFB at 50 mg/kg·day significantly improved cognitive performance of the SAMP8 mice in Morris water maze tests, similar to 150 mg/kg·day of resveratrol, a popular neuro-protective compound. Furthermore, TPFB treatment showed significant improvements in various AD markers in SAMP8 brains, which were restored to near control levels of the normal mice, SAMR1. TPFB significantly reduced the level of amyloid ß-peptide 42 (Aß42), inhibited hyperphosphorylation of the microtubule-associated protein Tau, induced phosphorylation of Ser9 of the glycogen synthase kinase 3ß (GSK-3ß), and decreased the expression of the proinflammatory cytokines TNFα, IL-6, and IL-1ß. Finally, TPFB also markedly reduced the level of serum derivatives of reactive oxygen metabolites (d-ROMs), a biomarker of oxidative stress in vivo. These results showed that dietary TPFB could effectively prevent age-related cognitive deficits and AD-like neurobiochemical changes, and may have a potential role in the prevention of Alzheimer's disease.

Multi-Target Anti-Alzheimer Activities of Four Prenylated Compounds from Psoralea Fructus.

Alzheimer's disease (AD) is an age-related neurodegenerative disease that is mediated by multiple signaling pathways. In recent years, the components of Psoralea Fructus (PF) have demonstrated some anti-Alzheimer effects both in vitro and in vivo. To further reveal the active compounds of PF and their mechanisms regulating key targets of AD, in this study, we identified four prenylated compounds from the 70% ethanolic aqueous extract of PF, namely bavachin, bavachinin, bavachalcone, and isobavachalcone. Multi-target bioactivity analysis showed that these compounds could differentially inhibit neuroinflammation, oxidative damage, and key AD-related protein targets, such as amyloid ß-peptide 42, ß-secretase, glycogen synthase kinase 3ß, and acetylcholinesterase. These compounds may generate beneficial effects in AD prevention and treatment.

[Chemical constituents from Fukeqianjin formula].

Fukeqianjin formula, a traditional Chinese medicine compound, consists of eight Chinese medicinal materials including roots of Moghania macrophylla, roots of Rosa laevigata, aerial parts of Andrographis paniculata, caulis of Mahonia fortunei, roots of Zanthoxylum dissitum, roots of Angelica sinensis, caulis of Spatholobus suberectus, and roots of Codonopsis pilosula. The chemical constituents from Fukeqianjin formula were studied in this paper. The compounds were separated and purified by repeated column chromatographic methods including silica gel, Sephadex LH-20, macroporous adsorptive resin, and reverse phase high performance liquid chromatography. And their chemical structures were determined by spectral data analyses. Thirty-eight compounds were obtained and identified as Z-3-butylidenephthalide (1), Z-ligustilide (2), senkyunolide I (3), senkyunolide H (4), vanillin (5), 7-O-methylwogonin (6), wogonin (7), panicolin (8), 19-hydroxy-8(17),13-labdadien-15,16-olide (9), andrograpanin (3,14-dideoxyandrographolide; 10), andrographolide (11), 14-deoxy-11,12-didehydroandrographolide (12), isoandrographolide (13), andrographin (2'-O-methylskullcapflavone, 14), biochanin A (15), 5-hydroxy-7,8,2',5'-tetramethoxyflavone (16), formononetin (17), daidzein (18), genistein (19), benzoic acid (20), vanillic acid (21), trans-ferulic acid (22), salicylic acid (23), daidzin (24), genistein-7-O-ß-D-apiofuranosyl-(1→6)-O-ß-D-glucopyranoside (25), apigenin-7-O-ß-D-glucuronide (26), andrographidin C (27), apigenin-7-O-ß-D-(6"-methyl)glucuronide (28), neoandrographolide (29), genistin (30), andrographiside (31), 14-deoxy-11,12-didehydroandrographiside (32), lobetyolin (33), epicatechin (34), catechin (35), palmatine (36), berberine (37), and jatrorrhizine (38), respectively. From the results of an individual medicinal material studies, it can be judged that compounds 17, 19, 24 and 30 as flavonoids came from the roots of M. macrophylla, compounds 36-38 as alkaloids came from the caulis of M. fortunei, compounds 6-8, 14, 16, and 27 as flavonoids as well as 9-13, 29, 31, and 32 as diterpenes came from the aerial parts of A. paniculata, compound 5 as phenols came from the roots of Z. dissitum, compounds 1-4 as phthalides as well as compound 22 as phenylpropanoids came from the roots of A. sinensis, compound 33 as alkynes came from the roots of C. pilosula, compounds 15, 17-19 as flavonoids as well as compound 21 as phenolic acids came from the caulis of S. suberectus. While compounds 34 and 35 as flavanoids could come from both the caulis of S. suberectus and roots of R. laevigata. The chemical composition of traditional Chinese medicine compound can be tracked from the original sources. This work provides a demonstration for the material basis study of traditional Chinese medicine compound. Compounds 25, 26 and 28 have not so far been isolated and identified from the above-mentioned single herb.

Cloning, expression, and characterization of a four-component O-demethylase from human intestinal bacterium Eubacterium limosum ZL-II.

Eubacterium limosum ZL-II was described to convert secoisolariciresinol (SECO) to its demethylating product 4,4'-dihydroxyenterodiol (DHEND) under anoxic conditions. However, the reaction cascade remains unclear. Here, the O-demethylase being responsible for the conversion was identified and characterized. Nine genes encoding two methyltransferase-Is (MT-I), two corrinoid proteins (CP), two methyltransferase-IIs (MT-II), and three activating enzymes (AE) were screened, cloned, and expressed in Escherichia coli. Four of the nine predicted enzymes, including ELI_2003 (MT-I), ELI_2004 (CP), ELI_2005 (MT-II), and ELI_0370 (AE), were confirmed to constitute the O-demethylase in E. limosum ZL-II. The complete O-demethylase (combining the four components) reaction system was reconstructed in vitro. As expected, the demethylating products 3-demethyl-SECO and DHEND were both produced. During the reaction process, ELI_2003 (MT-I) initially catalyzed the transfer of methyl group from SECO to the corrinoid of ELI_2004 ([CoI]-CP), yielding demethylating products and [CH3-CoIII]-CP; then ELI_2005 (MT-II) mediated the transfer of methyl group from [CH3-CoIII]-CP to tetrahydrofolate, forming methyltetrahydrofolate and [CoI]-CP. Due to the low redox potential of [CoII]/[CoI], [CoI]-CP was oxidized to [CoII]-CP immediately in vitro, and ELI_0370 (AE) was responsible for catalyzing the reduction of [CoII]-CP to its active form [CoI]-CP. The active-site residues in ELI_2003, ELI_2005, and ELI_0370 were subsequently determined using molecular modeling combined with site-directed mutagenesis. To our knowledge, this is the first study on the identification and characterization of a four-component O-demethylase from E. limosum ZL-II, which will facilitate the development of method to artificial synthesis of related bioactive chemicals.

Usefulness of the heart-rate variability complex for predicting cardiac mortality after acute myocardial infarction.

BACKGROUND: Previous studies indicate that decreased heart-rate variability (HRV) is related to the risk of death in patients after acute myocardial infarction (AMI). However, the conventional indices of HRV have poor predictive value for mortality. Our aim was to develop novel predictive models based on support vector machine (SVM) to study the integrated features of HRV for improving risk stratification after AMI. METHODS: A series of heart-rate dynamic parameters from 208 patients were analyzed after a mean follow-up time of 28 months. Patient electrocardiographic data were classified as either survivals or cardiac deaths. SVM models were established based on different combinations of heart-rate dynamic variables and compared to left ventricular ejection fraction (LVEF), standard deviation of normal-to-normal intervals (SDNN) and deceleration capacity (DC) of heart rate. We tested the accuracy of predictors by assessing the area under the receiver-operator characteristics curve (AUC). RESULTS: We evaluated a SVM algorithm that integrated various electrocardiographic features based on three models: (A) HRV complex; (B) 6 dimension vector; and (C) 8 dimension vector. Mean AUC of HRV complex was 0.8902, 0.8880 for 6 dimension vector and 0.8579 for 8 dimension vector, compared with 0.7424 for LVEF, 0.7932 for SDNN and 0.7399 for DC. CONCLUSIONS: HRV complex yielded the largest AUC and is the best classifier for predicting cardiac death after AMI.

A computer-aided diagnostic algorithm improves the accuracy of transesophageal echocardiography for left atrial thrombi: a single-center prospective study.

OBJECTIVES: We investigated whether transesophageal echocardiography (TEE) assisted with a computer-aided diagnostic (CAD) algorithm was superior to TEE in diagnosing left atrial (LA)/left atrial appendage (LAA) thrombi in patients with atrial fibrillation (AF) in a single prospective study. METHODS: Transesophageal echocardiography was performed in patients with AF, and images were reconstructed. Gray level co-occurrence matrix-based features were calculated and then classified using an artificial neural network. The original data and processed images by the CAD system were studied by 5 radiologists independently in a blind manner. The diagnostic performance of each radiologist was evaluated. RESULTS: One hundred thirty patients with AF were investigated. Thirty-one patients (23.9%) had a diagnosis of LA/LAA thrombi. The mean sensitivity ± SD of TEE for LA/LAA thrombi was 0.933 ± 0.027, which was noticeably improved by CAD (0.955 ± 0.021; P < .05). The specificity of TEE was 0.811 ± 0.055, which was markedly lower than that by TEE plus CAD (0.970 ± 0.009; P < .05). The positive predictive value of TEE was low (0.613 ± 0.073) compared to that of TEE plus CAD (0.908 ± 0.027; P < .001), whereas the negative predictive values were comparable for TEE, CAD, and TEE plus CAD. Diagnosis of an LA/LAA thrombus by TEE plus CAD had a higher accuracy rate (0.966 ± 0.011) than that by TEE (0.840 ± 0.047; P < .01). The mean area under the receiver operating characteristic curve (Az) for TEE was 0.834 ± 0.009 (95% confidence interval [CI], 0.815-0.852), which was markedly lower than the Az for TEE plus CAD (0.932 ± 0.005; 95% CI, 0.921-0.943). The use of CAD significantly improved the Az values for all 5 radiologists (P < .001). CONCLUSIONS: The CAD algorithm significantly improves the diagnostic accuracy of TEE for LA/LAA thrombi in patients with AF.

[Inhibitory effects of Rhodiola plants and their oligomeric proanthocyanidins on tyrosinase and Abeta42 aggregation].

Tyrosinase is a key enzyme related to skin pigmentation disorders of elderly people, while self-aggregation of the amyloid-beta peptide, Abeta42, has been considered as a key event in the pathogenesis of Alzheimer's disease (AD). The present study was undertaken to investigate the inhibitory effects of 20 samples from Rhodiola species on tyrosinase and Abeta42 aggregation, and to isolate their corresponding bioactive components. The results demonstrated that the oligomeric proanthocyanidins (OPCs) commonly found in Rhodiola species were the major bioactive components corresponding to their anti-tyrosinase and anti-Abeta42 aggregation bioactivities. Salidroside, a representative compound of Rhodiola plants, proved not to be active in the present studies.

Analysis of chemical constituents and taxonomic similarity of Salvia species in China using LC/MS.

Salvia species have an extensive distribution and a long history of medical use in China. In this study, chemical differences between different Salvia species were thoroughly investigated, and 86 constituents were characterized through a sensitive HPLC-DAD-ESI-MS (n) method. In total, 19 Salvia species were screened. Our study suggested that Ser. Brachylomae, Ser. Digitaloidites, Ser. Castaneae, and Ser. Miltiorrhizae were the sibling series (Ser. is short for series) and that Ser. Brachylomae, Ser. Maximowicziana, and Ser. Campanulatae were unique with regard to their constituents in addition to having componential affinity. This study offered a simple chemotaxonomy approach and a reasonable bioactivity interpretation of Salvia species.

[Preliminary exploration of inhibitory activities of Salvia species on PTP1B].

An in vitro screening model was applied to test the inhibitory activities of 17 Salvia species on protein tyrosine phosphatase 1B (PTP1B). Root methanol extracts from wild-collected Salvia species were analyzed using this model. Most of the samples tested showed positive activities on human PTP1B. The inhibition rates of Salvia crude extracts varied from 9.76% to 100% at 30 microg x mL(-1), with the most convincing effects coming from Salvia evansiana and Salvia castanea. HPLC analysis revealed seven components shared by Salvia samples could be related to the inhibitory activities.

Plasma pharmacokinetics and cerebral nuclei distribution of major constituents of Psoraleae fructus in rats after oral administration.

BACKGROUND: The fruit of Psoralea corylifolia L., Psoraleae fructus (PF), is widely used in traditional Chinese medicine as a well-known herbal tonic. Previous studies have shown that PF and its major constituents may have potential values in the treatment of Parkinson and Alzheimer diseases, though their pharmacokinetics and brain distribution were largely unknown. PURPOSE: To develop a liquid chromatographic-tandem mass spectrometry (LC-MS/MS) method for simultaneous studies of the plasma pharmacokinetics and cerebral nuclei (including cerebellum, thalamus, brainstem, hippocampus, corpus striatum and cortex) distribution in rats of eleven known PF compounds following as psoralen, isopsoralen, psoralidin, bavachin, bavachinin, isobavachin, isobavachalcone, bavachalcone, neobavaisoflavone, corylifol A, and corylin. METHODS: Rats were orally administered via gavage at a single dose of PF extract at 1.2 g/kg. The eleven known PF compounds were extracted from rat plasma and cerebral nuclei at different time points, and then determined by the established LC-MS/MS method. Non-compartmental pharmacokinetic profiles were calculated, and the distribution in rat plasma and cerebral nuclei were compared. RESULTS: The results showed that all the tested compounds were quickly absorbed into rat plasma and distributed almost evenly to the cerebral nuclei. The distribution concentrations at different nuclei varied at one determined time point, but the overall trends were basically similar to the plasma concentration-time results. Psoralen and isopsoralen, the two highest coumarins contained in PF, displayed far higher plasma concentrations (AUC0→∞, plasma≈53,884∼65,578 ng·h/ml) and central nervous system penetration (AUC0→∞, brain nuclei ≈44,659∼65,823 ng·h/g) than the prenylflavonoids (other compounds except psoralidin, AUC0→∞, plasma≈69∼324 ng·h/ml; AUC0→∞, brain nuclei ≈119∼3662 ng·h/g). However, the total brain-to-plasma ratios of the prenylflavonoids were higher than the coumarins, suggesting the prenylflavonoids can more readily enter the brain than the coumarins. CONCLUSION: The established LC-MS/MS method is sensitive and specific for the simultaneous quantitation of the eleven PF compounds in rat plasma and cerebral nuclei. The results of plasma pharmacokinetics and cerebral nuclei distribution may reveal the possible substance basis for the CNS activities of PF, and highlight the application possibility of PF and its major constituents in the treatment of Parkinson and Alzheimer diseases.

Field evaluation of two commercial RT-rtPCR assays for porcine reproductive and respiratory syndrome virus detection using sera from ill and healthy pigs, China.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a highly contagious respiratory virus causing severe morbidity in pigs worldwide. Control strategies for PRRSV often rely on detecting PRRSV, culling or isolating sick pigs, disinfecting pig barns, vaccination, and monitoring for virus spread. Given the high economic impact of PRRSV on pig farms, there is a great need for rapid and reliable PRRSV detection assays. We compared the performance of 2 commercial reverse-transcription real-time PCR (RT-rtPCR) assays, the VetMAX PRRSV NA and EU reagents (ABI assay) and the PRRSV general RT-rtPCR kit (Anheal assay), for the molecular detection of PRRSV in sera collected from pigs in China. Between June and September 2015, sera were collected from 219 healthy and 104 suspected PRRSV-infected pigs on 4 farms in China. Employing blinding, the 2 assays were run by 2 laboratories (Guangzhou Animal Health Inspection Institute [GAHII] and Sun Yat-sen University [SYSU] laboratories) and compared. Although both assays detected PRRSV with 100% specificity at both laboratories, the sensitivity (95% vs. 78% at GAHII; 94% vs. 72% at SYSU Laboratory) and the reproducibility (kappa value 0.933 vs. 0.931) were slightly better for the ABI assay compared to the Anheal assay.

Computerized-aid diagnosis of breast mass using ultrasound image.

This paper presents a comparative study of the diagnostic results of the ultrasologists with/without using a novel enhancement algorithm for breast ultrasonic images based on fuzzy entropy principle and textural information. Totally, 350 ultrasound images of 115 cases were analyzed including 59 benign and 56 malignant lesions. The original breast images were fuzzified, the edge and textural information were extracted, and the images were enhanced. The original and enhanced images were assessed and evaluated by ultrasologists using double blind method before and after enhancement. The diagnostic sensitivity and specificity were calculated by the areas (Az) under the receiver operating characteristic (ROC) curves. And the two diagnostic results before and after enhancement were compared by Chi-square test in a 2 x 2 table. The results demonstrated that the discrimination rate of breast masses had been highly improved after employing the novel enhancement algorithm. The result indicates the sensitivity could be raised from 74.3% to 89.3% with the false-positive rate 14.3%, and the area (Az) under the ROC curve of diagnosis also increased from 0.84 to 0.93. The novel enhancement algorithm can increase the classification accuracy and decrease the rate of missing and misdiagnosis, and it is useful for breast cancer control.

[Analysis of ITS sequences of some medicinal plants and their related species in Salvia].

Molecular systematic techniques were applied to reveal the genetic diversity of medicinal plants and their related species in Salvia. The internal transcribed spacer (ITS) as well as 5.8S rDNA sequences of 27 samples of Salvia were amplified using PCR method and sequenced. Mega 3.1 was used to analyze the genetic diversity within genus. The complete sequences of ITS plus 5.8S rDNA are about 612-617 bp. A phylogenetic tree generated by Neighbor-Joining method partly supported the morphological classification within Salvia, but incompatible results were also obtained in the treatment of phylogenetic positions of some species such as Salvia trijuga, Salvia flava var. flava and Salvia flava var. megalentha. The ITS regions of present Salria species showed considerable variation between subgenera in contrast with the conservative 5.8S rDNA sequences. The native Salvia species might have a different origin from the foreign species. The phylogenetic positions of subgenera and sections inferred by ITS analysis were comparable with that of traditional classification, while the phylogeny within sections is still doubtful due to limited information in ITS sequence and need to be further proved by other evidence. ITS analysis in this study supports the rationality of using species from Drymosphace section as substitute drug resources of Dan shen, but also reveals significant genetic differences between high mountain Dan shen species such as Salvia przewalskii with traditional Dan shen origins.

[Identification of metastasis-associated proteins of ovarian cancer by proteomics].

OBJECTIVE: To investigate the differenal protein expression profiles of ovarian tumor cell lines with distinct metastatic abilities. METHODS: The ovarian cancer cell line HO8910 and HO8910pm, derived from same parental cells but exhibited different metastatic ability, were investigated by two-dimensional gel electrophoresis (2-DE)-MALDI-TOF-MS proteomic approach. RESULTS: Thirty-nine proteins were detected by 2-DE to have expression disparity levels over 2 folds between two cell lines. Eighteen of them were identified by MALDI-TOF-MS. The proteins are involved in apoptosis, extra cellular matrix (ECM), cytoskeleton, growth factor, glycolysis, protein metabolism and immune system. CONCLUSION: The data are valuable for the identification of differentially expressed proteins involved in the biological behavior of human ovarian cancer.

Proteomics-based analysis of a pair of glioma cell lines with different tumor forming characteristics.

Glioma is the most common malignant disease in the brain, and recurrence is the main cause of death from this disease. Tumor recurrence involves multiple steps, and requires the accumulation of the altered expression of many different proteins. Identification of the recurrence associated protein profile in glioma cell lines will be helpful in clarifying the molecular mechanisms underlying glioma recurrence. In this report, two glioma cell lines with distinct tumor forming ability in vitro and in vivo were chosen and the different protein expression patterns were analyzed by proteomics method. To confirm the utility of this method, we validated the differential expression of one protein, cathepsin D, by immunohistochemistry analysis. Forty-six proteins appeared differently between two cell lines and 18 of them were identified. These 18 are involved in cell proliferation, DNA replication, protein synthesis, invasion, angiogenesis and neurotrophic factor. All of these molecules are important in tumor growth, and a subset of them may be related to glioma recurrence. These findings may contribute to the discovery of new diagnostic markers and therapeutic targets of glioma.

Josephson current through a quantum dot coupled to a Majorana zero mode.

Employing the Green's function method, we investigate the Josephson current through a quantum dot side coupled to a topological superconducting nanowire sustaining a pair of Majorana zero modes. It is found that the Josephson current is blocked when the quantum dot is side coupled to a superconducting nanowire in a topologically trivial phase. However, when the topological superconducting nanowire transitions from a topologically trivial to a topologically non-trivial phase, an Andreev bound state arises at the zero Fermi energy of the quantum dot due to leakage of the Majorana zero mode. Thus a Josephson current can be induced by leakage of the Majorana zero mode into the quantum dot. The Josephson current shows a plateau-like structure and a clear-cut trivial/non-trivial phase transition, as a function of a Zeeman field imposed on the system. The transition and plateau-like structure can be used to probe the existence of the Majorana zero mode. The current-phase relation has also been studied.

Identification of proteins of human colorectal carcinoma cell line SW480 by two-dimensional electrophoresis and MALDI-TOF mass spectrometry.

AIM: To conduct the proteomic analysis of human colorectal carcinoma cell line, SW480 by using two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption /ionization-time of flight mass spectrometry (MALDI-TOFMS). METHODS: The total proteins of human colorectal carcinoma cell line, SW480 were separated with 2-DE by using immobilized pH gradient strips and visualized by staining with silver nitrate. The gel images were acquired by scanner and 2-DE analysis software, Image Master 2D Elite. Nineteen distinct protein spots were excised from gel randomly and digested in gel by TPCK-trypsin. Mass analysis of the tryptic digest peptides mixture was performed by using MALDI-TOF MS. Peptide mass fingerprints (PMFs) obtained by the MALDI-TOF analysis were used to search NCBI, SWISS-PROT and MSDB databases by using Mascot software. RESULTS: PMF maps of all spots were obtained by MALDI-TOF MS and thirteen proteins were preliminarily identified. CONCLUSION: The methods of analysis and identification of protein spots of tumor cells in 2-DE gel with silver staining by MALDI-TOF MS derived PMF have been established. Protein expression profile of SW480 has been obtained. It is demonstrated that a combination of proteomics and cell culture is a useful approach to comprehend the process of colon carcinogenesis.

[Expression of IgVH and B7-1 in proteome of the human colorectal carcinoma cell lines].

OBJECTIVE: To conduct a proteomic analysis of human colorectal carcinoma cell lines LS174T and SW480 by two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). METHODS: The total proteins of human colorectal carcinoma cell lines LS174T and SW480 were separated with 2-DE using immobilized pH gradient strips and analyzed by MALDI-TOF-MS to obtain peptide mass fingerprints (PMFs). Proteins were identified by using Mascot software to search protein databases. RESULTS: Good resolution 2-DE maps were obtained. Some proteins including immunoglobulin heavy chain variable region (IgVH) and co-stimulatory molecule B7-1 were identified. IgVH and B7-1 were confirmed by electrospray ionization tandem spectrometry (ESI-MS/MS) and immunocytochemistry. CONCLUSION: There are IgVH and B7-1 expressions in human colorectal carcinoma cell lines LS174T and SW480. Results obtained will help to elucidate the mechanisms of tumor immune escape.