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Xiang S, Fuji K, Sato S, Xiao S, Bird JP, Aoki N, Ochiai Y. Metal-insulator transition in the quasi-one-dimensional transport of fractional quantum Hall states. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:202201. [PMID: 25920938 DOI: 10.1088/0953-8984/27/20/202201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We investigate edge state transmission in quantum point contacts (QPCs) in the fractional quantum-Hall regime, finding behavior reminiscent of a metal-insulator transition. The transition is suggested by an unusual behavior of the differential conductance in the fractional-quantum-Hall regime, and by the presence of a fixed point and universal scaling in the temperature dependence of the linear conductance. Noting that the 0.7 feature evolves continuously into a last fractional plateau at high magnetic fields, we suggest that this still unresolved feature may itself be viewed as a manifestation of a local, microscopic, metal-insulator transition.
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Wang G, Xiao S, Gao C. The effects of cardiopulmonary bypass on pulmonary function during robotic cardiac surgery. Perfusion 2015; 30:213-8. [PMID: 25784166 DOI: 10.1177/0267659114537327] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND We aimed to investigate the effects of cardiopulmonary bypass (CPB) on pulmonary function under the conditions of one-lung ventilation (OLV) and carbon dioxide pneumothorax in robotic cardiac surgery. METHODS Ninety-eight patients underwent robotic cardiac surgery using the da Vinci Surgical System, including 58 on-pump surgeries and 40 off-pump surgeries. Respiratory parameters and arterial blood gases were assessed at the following time points: 25 min after the induction of anesthesia under two-lung ventilation (T1), 25 min after OLV (T2), 25 min after the termination of CPB under OLV in the on-pump group or 25 min after the main surgery intervention in the off-pump group (T3) and 20 min before the end of surgery (T4). Dynamic lung compliance (Cdyn), alveolar-arterial PO2 difference (PA-aDO2), oxygenation index (OI) and artery-alveolar O2 pressure ratio (a/A) were calculated. RESULTS No significant differences in pulmonary function parameters between T2 and T3 were observed in the off-pump group. However, in the on-pump group, compared with those at T2, PETCO2, Ppeak, PaCO2 and PA-aDO2 at T3 were higher, whereas SpO2, Cdyn, PaO2, OI and a/A were lower (p<0.05). Comparisons between the two groups at T3 indicated that SpO2, Cdyn, PaO2, OI and a/A were higher, while Ppeak, PaCO2 and PA-aDO2 were lower in the off-pump group (p<0.01). CONCLUSIONS In robotic cardiac surgery under the conditions of OLV and carbon dioxide pneumothorax, CPB worsened pulmonary function and tolerance to OLV and carbon dioxide pneumothorax.
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Zhou X, Liu GK, Xiao S, Zhang SS. First Report of Meloidogyne graminicola Infecting Banana in China. PLANT DISEASE 2015; 99:420. [PMID: 30699708 DOI: 10.1094/pdis-08-14-0810-pdn] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Bananas (Musa spp.) are one of world's most popular fruits, and China is the third largest banana-producing country in the world. Root-knot nematodes, Meloidogyne spp., are common pests of banana worldwide, but damage to this crop caused by M. graminicola has not been reported up to now. During a survey of root-knot nematode species infecting banana in Fujian Province, China, swollen, galled primary and secondary root samples of Musa nana cv. Tianbao (AAA) were collected from two commercial fields in Nanjing County in May 2013. The affected plants did not exhibit obvious above-ground symptoms. Seriously infected roots were malformed and dehiscent, with the tissue discolored and rotting. Examination of symptomatic roots revealed one to several females of Meloidogyne sp. within each gall, with egg masses that were often completely embedded within the gall without protruding through the root surface, and with second-stage juveniles (J2) hatched inside the galls. Population densities of this nematode ranged from 452 to 2,056 eggs and J2 per 5 g of fresh roots. Males were rarely observed. Morphological measurements of 25 females and 20 J2 matched the original description of M. graminicola (1). The perineal patterns of females were dorsoventrally ovoid, with low to moderately high and round dorsal arches and lacking obvious lateral lines; striae were smooth and some were broken by a few obvious irregular, zig-zag striae in the dorsal part of the pattern; phasmids were close together (13.1 to 19.7 μm). The J2 had long tapered tails (63.4 to 75.5 μm), with long narrow hyalines (13.1 to 19.9 μm) and marked clavate termini. DNA was extracted from one mature female. The ITS1-5.8S-ITS2 rDNA region was amplified with V5367/26S (TTGATTACGTCCCTGCCCTTT/TTTCACTCGCCGTTACTAAGG) (2) and the COII and IRNA mtDNA genes were amplified with C2F3/MRH106 (GGTCAATG TTCAGAAATTTGTGG/AATTTCTAAAGACTTTTCTTAGT) (3) and then sequenced. The sequences were subjected to a database search using BLAST to verify the identity. Sequences from the ITS region were 788 bp (GenBank Accession Nos. KM111531 and KM236560) and were 96.8 to 99.1% identical to the known sequences of M. graminicola in Genbank. Sequences from the mtDNA were 666 bp (KM111533 and KM236559) and showed 99.1 to 99.4% homology with the known sequences of M. graminicola (KJ139963 and HG529223). In glasshouse tests, banana plantlets (M. nana cv. Tianbao) about 20 cm high were transplanted in 25-cm-diameter pots and inoculated with 5,000 J2 of each collected population of M. graminicola replicated six times; a noninoculated control was included. After 15 weeks, all inoculated plants were stunted and chlorotic. Galling symptoms on roots were similar to those in the field, and dissection of galled root tissue revealed that different life stages of the nematode were present, with population densities ranging from 1,238 to 6,562 eggs and J2 per 5 g of fresh roots. The noninoculated control plants grew well and had no galling symptoms on the roots. These results confirmed the nematodes' pathogenicity on banana. On the basis of these results, the root-knot nematodes isolated from banana in Nanjing County were confirmed as M. graminicola. To our knowledge, this is the first report of a natural infection of banana with M. graminicola. References: (1) A.M. Golden and W. Birchfield. Plant Dis. Rep. 52:423, 1968. (2) T. C. Vrain et al. Fund. Appl. Nematol. 15:565, 1992. (3) J. Xu et al. Eur. J. Plant Pathol. 110:309, 2004.
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Li Z, Zhao B, Zhang Y, Tu C, Zheng Y, He X, Xiao S. Failure of rapamycin in the treatment of multiple haemangiomas associated with Maffucci syndrome. Clin Exp Dermatol 2015; 40:951-4. [PMID: 25623423 DOI: 10.1111/ced.12545] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/20/2014] [Indexed: 11/30/2022]
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Zhang Y, Zhang D, Tu C, Zhou P, Zheng Y, Peng Z, Feng Y, Xiao S, Li Z. Wnt5a is involved in the pathogenesis of cutaneous lichen planus. Clin Exp Dermatol 2015; 40:659-64. [PMID: 25581355 DOI: 10.1111/ced.12561] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2014] [Indexed: 12/24/2022]
Abstract
BACKGROUND Cutaneous lichen planus (CLP) is a chronic inflammatory and immune-mediated disease. Wnt5a is one of the most extensively studied Wnt proteins, and has important functions in stimulating inflammation, cell proliferation, cell fate determination and cell differentiation. Wnt5a expression in CLP has not been comprehensively studied to date. AIM To determine the expression and distribution of Wnt5a in CLP. METHODS Skin samples were obtained from patients with CLP and healthy controls (HCs). The WNT5A gene was detected by real-time quantitative PCR, and Wnt5a protein by immunohistochemical analysis and western blotting. RESULTS WNT5A mRNA was upregulated in CLP samples compared with the HC skin samples (P < 0.001). Wnt5a protein was overexpressed in all layers of the epidermis and dermis in CLP lesions compared with HC skin (all P < 0.001). These results were confirmed by western blotting. CONCLUSIONS The data presented in this study suggest that Wnt5a pathway may play an important role in the pathogenesis of CLP.
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Shi BJ, Jiang Y, Gao T, Xiao S, Xue M, Liu Y, Hao J, Diao QC. Epidermolysis bullosa pruriginosa: two novel mutations (A2054V and G2233R) in the COL7A1 gene. J Eur Acad Dermatol Venereol 2014; 30:175-8. [PMID: 25284350 DOI: 10.1111/jdv.12683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Gu B, Yang Z, Huang S, Xiao S, Zhang B, Yang L, Zhao J, Zhao Z, Shen J, Liu J. Radiation-induced Brachial Plexus Injury After Radiotherapy for Nasopharyngeal Carcinoma. Jpn J Clin Oncol 2014; 44:736-742. [DOI: 10.1093/jjco/hyu062] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Shi BJ, Xiao S, Zhang Z, Lü J, Xue M, Jiang Y, Liu Y, Hao J, Diao QC. The ATP2C1 gene in Hailey-Hailey disease patients: one novel deletion and one novel splicing mutation. J Eur Acad Dermatol Venereol 2014; 29:2495-7. [PMID: 24981372 DOI: 10.1111/jdv.12603] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Godini H, Xiao S, Kim M, Holst N, Jašo S, Görke O, Steinbach J, Wozny G. Experimental and model-based analysis of membrane reactor performance for methane oxidative coupling: Effect of radial heat and mass transfer. J IND ENG CHEM 2014. [DOI: 10.1016/j.jiec.2013.09.022] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Wang YF, Xiao S, Huang YK, Zhou X, Zhang SS, Liu GK. First Report of Meloidogyne enterolobii on Carrot in China. PLANT DISEASE 2014; 98:1019. [PMID: 30708858 DOI: 10.1094/pdis-02-14-0119-pdn] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Carrot (Daucus carota var. sativus) is one of the 10 most economically important vegetable crops in the world. Recently, stunted and yellowing carrots grown on sandy soil in several commercial fields were observed in Dongshan County, Fujian Province, China. Many round to irregular shaped lumps and swellings were present on the surface of tap and fibrous roots, often with secondary roots emerging from the galls on taproots. Severe infection caused short, stubby, forked taproots leading to losses in quality and marketability. Meloidogyne sp. females and egg masses were dissected from the galls. The perineal patterns from 20 females were oval shaped with moderate to high dorsal arches and mostly lacking obvious lateral lines. The second-stage juvenile mean body length (n = 20) was 416 (390 to 461) μm; lateral lips were large and triangular in face view; tail was thin and length was averaged 56.1 (49.8 to 62.1) μm, with a broad, bluntly rounded tip. These morphological characteristics matched the original description of M. enterolobii (5). Species identity was further explored by sequencing the mitochondrial DNA (mtDNA) region between COII and the lRNA genes using primers C2F3/MRH106 (GGTCAATGTTCAGAAATTTGTGG/AATTTCTAAAGACTTTTCTTA GT) (4). A DNA fragment of ~840 bp was obtained and the sequence (GenBank Accession No. KJ146864) was compared with those in GenBank using BLAST and was 100% identical to the sequences of M. enterolobii and M. mayaguensis, a synonym of M. enterolobii (4). Part of the rDNA spanning ITS1, 5.8S gene, ITS2 was amplified with primers V5367/26S (TTGATTACGTCCCTGCCCTTT/TTTCACTCGCCGTTACTAAGG) (3), and the sequence obtained (KJ146863) was 99 to 100% identical to sequences of M. enterolobii (KF418369.1, KF418370.1, JX024149.1, and JQ082448.1). For further confirmation, M. enterolobii specific primers Me-F/Me-R (AACTTTTGTGAAAGTGCCGCTG/TCAGTTCAGGCAGGATCAACC) (2) were used for amplification of the rDNA-IGS2 sequences of eight populations of the nematode from three localities. A 200-bp amplification product was produced by each population, whereas no product was amplified from control populations of M. incognita or M. javanica. A single product of ~320 bp was obtained using primers 63VNL/63VTH (GAAATTGCTTTATTGTTACTAAG/TAGCCACAGCAAAATAGTTTTC ) (1) from the mtDNA 63-bp repeat region for these populations, and the sequence (KJ146861) showed 100% identity with sequences of M. enterolobii (AJ421395.1, JF309159.1, and JF309160.1). Therefore, the population of Meloidogyne sp. on carrot was confirmed to be M. enterolobii. This nematode has been reported to infect more than 20 plant species belonging to seven families, including Annonaceae, Cucurbitaceae, Convolvulaceae, Fabaceae, Marantaceae, Myrtaceae, and Solanaceae in China. To our knowledge, this is the first report of infection of carrot by M. enterolobii and the first record of M. enterolobii parasitizing a plant in the family Apiaceae in China. M. enterolobii has been reported in Guangdong and Hainan provinces, China. This is the first report of M. enterolobii in Fujian Province, in southeast China. References: (1) V. C. Blok et al. Nematology 4:773, 2002. (2) H. Long et al. Acta Phytopathol. Sin. 36:109, 2006. (3) T. C. Vrain et al. Fundam. Appl. Nematol. 15:565, 1992. (4) J. Xu et al. Eur. J. Plant Pathol. 110:309, 2004. (5) B. Yang and J. D. Eisenback. J. Nematol. 15:381, 1983.
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Xiang S, Xiao S, Fuji K, Shibuya K, Endo T, Yumoto N, Morimoto T, Aoki N, Bird JP, Ochiai Y. On the zero-bias anomaly and Kondo physics in quantum point contacts near pinch-off. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:125304. [PMID: 24599094 DOI: 10.1088/0953-8984/26/12/125304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We investigate the linear and non-linear conductance of quantum point contacts (QPCs), in the region near pinch-off where Kondo physics has previously been connected to the appearance of the 0.7 feature. In studies of seven different QPCs, fabricated in the same high-mobility GaAs/AlGaAs heterojunction, the linear conductance is widely found to show the presence of the 0.7 feature. The differential conductance, on the other hand, does not generally exhibit the zero-bias anomaly (ZBA) that has been proposed to indicate the Kondo effect. Indeed, even in the small subset of QPCs found to exhibit such an anomaly, the linear conductance does not always follow the universal temperature-dependent scaling behavior expected for the Kondo effect. Taken collectively, our observations demonstrate that, unlike the 0.7 feature, the ZBA is not a generic feature of low-temperature QPC conduction. We furthermore conclude that the mere observation of the ZBA alone is insufficient evidence for concluding that Kondo physics is active. While we do not rule out the possibility that the Kondo effect may occur in QPCs, our results appear to indicate that its observation requires a very strict set of conditions to be satisfied. This should be contrasted with the case of the 0.7 feature, which has been apparent since the earliest experimental investigations of QPC transport.
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Fransson J, Kang MG, Yoon Y, Xiao S, Ochiai Y, Reno JL, Aoki N, Bird JP. Tuning the Fano resonance with an intruder continuum. NANO LETTERS 2014; 14:788-793. [PMID: 24460187 DOI: 10.1021/nl404133d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Through a combination of experiment and theory we establish the possibility of achieving strong tuning of Fano resonances (FRs), by allowing their usual two-path geometry to interfere with an additional, "intruder", continuum. As the coupling strength to this intruder is varied, we predict strong modulations of the resonance line shape that, in principle at least, may exceed the amplitude of the original FR itself. For a proof-of-concept demonstration of this phenomenon, we construct a nanoscale interferometer from nonlocally coupled quantum point contacts and utilize the unique features of their density of states to realize the intruder. External control of the intruder coupling is enabled by means of an applied magnetic field, in the presence of which we demonstrate the predicted distortions of the FR. This general scheme for resonant control should be broadly applicable to a variety of wave-based systems, opening up the possibility of new applications in areas such as chemical and biological sensing and secure communications.
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Lee J, Han JE, Xiao S, Song J, Reno JL, Bird JP. Formation of a protected sub-band for conduction in quantum point contacts under extreme biasing. NATURE NANOTECHNOLOGY 2014; 9:101-105. [PMID: 24441984 DOI: 10.1038/nnano.2013.297] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 12/05/2013] [Indexed: 06/03/2023]
Abstract
Managing energy dissipation is critical to the scaling of current microelectronics and to the development of novel devices that use quantum coherence to achieve enhanced functionality. To this end, strategies are needed to tailor the electron-phonon interaction, which is the dominant mechanism for cooling non-equilibrium ('hot') carriers. In experiments aimed at controlling the quantum state, this interaction causes decoherence that fundamentally disrupts device operation. Here, we show a contrasting behaviour, in which strong electron-phonon scattering can instead be used to generate a robust mode for electrical conduction in GaAs quantum point contacts, driven into extreme non-equilibrium by nanosecond voltage pulses. When the amplitude of these pulses is much larger than all other relevant energy scales, strong electron-phonon scattering induces an attraction between electrons in the quantum-point-contact channel, which leads to the spontaneous formation of a narrow current filament and to a renormalization of the electronic states responsible for transport. The lowest of these states coalesce to form a sub-band separated from all others by an energy gap larger than the source voltage. Evidence for this renormalization is provided by a suppression of heating-related signatures in the transient conductance, which becomes pinned near 2e(2)/h (e, electron charge; h, Planck constant) for a broad range of source and gate voltages. This collective non-equilibrium mode is observed over a wide range of temperature (4.2-300 K) and may provide an effective means to manage electron-phonon scattering in nanoscale devices.
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Zhou H, Luo H, Xiao S, Wang H, Gong G. Predictors for dose reduction of antiviral therapy in older patients infected with hepatitis C virus: a meta-regression analysis. Eur J Clin Microbiol Infect Dis 2013; 33:491-8. [PMID: 24193376 DOI: 10.1007/s10096-013-1992-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 09/30/2013] [Indexed: 01/19/2023]
Abstract
Treatment-related adverse events (AE) were more frequent in older patients treated by pegylated interferon (PEG-IFN) plus ribavirin (RBV) for chronic hepatitis C (CHC), and most of them required dose reduction. A meta-regression analysis was conducted to explore the possible reasons for this occurrence. We searched MEDLINE, EMBASE, and Web of Science through May 2013, for clinical trials examining the safety of PEG-IFN plus RBV in elderly patients with CHC. Data were extracted for host, viral, and outcome information. Single-arm meta-analysis was performed to evaluate AE. Meta-regression analysis was conducted to explore predictors for dose reduction secondary to AE. Eighteen observational studies met the inclusion criteria. The overall incidences of AE were 61.3%. Dose reductions due to AE were 54.2%. In patients with genotype 1, the rate of sustained virological response (SVR) was 36.9%. In patients with genotypes 2 or 3, the rate of SVR was 72.8%. Patients with more dose reduction due to AE have a tendency toward a lower likelihood of obtaining SVR (coefficient:-0.529), especially for genotype 1 patients. Host factors (male gender, coefficient 4.403; higher body weight, coefficient 0.140; and advanced fibrosis stage, coefficient 1.582) and viral factors (HCV genotype 1, coefficient 2.279) have a significant impact on dose reduction due to AE. Some host and viral factors affected dose reduction due to AE. Increasing rates of fibrosis with age may play a role as a mechanism affecting dose reduction secondary to AE and SVR in different age groups.
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Pang K, Tang Q, Schiffbauer JD, Yao J, Yuan X, Wan B, Chen L, Ou Z, Xiao S. The nature and origin of nucleus-like intracellular inclusions in Paleoproterozoic eukaryote microfossils. GEOBIOLOGY 2013; 11:499-510. [PMID: 24033870 DOI: 10.1111/gbi.12053] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Accepted: 07/23/2013] [Indexed: 05/19/2023]
Abstract
The well-known debate on the nature and origin of intracellular inclusions (ICIs) in silicified microfossils from the early Neoproterozoic Bitter Springs Formation has recently been revived by reports of possible fossilized nuclei in phosphatized animal embryo-like fossils from the Ediacaran Doushantuo Formation of South China. The revisitation of this discussion prompted a critical and comprehensive investigation of ICIs in some of the oldest indisputable eukaryote microfossils-the ornamented acritarchs Dictyosphaera delicata and Shuiyousphaeridium macroreticulatum from the Paleoproterozoic Ruyang Group of North China-using a suite of characterization approaches: scanning electron microscopy (SEM), transmission electron microscopy (TEM), and focused ion beam scanning electron microscopy (FIB-SEM). Although the Ruyang acritarchs must have had nuclei when alive, our data suggest that their ICIs represent neither fossilized nuclei nor taphonomically condensed cytoplasm. We instead propose that these ICIs likely represent biologically contracted and consolidated eukaryotic protoplasts (the combination of the nucleus, surrounding cytoplasm, and plasma membrane). As opposed to degradational contraction of prokaryotic cells within a mucoidal sheath-a model proposed to explain the Bitter Springs ICIs-our model implies that protoplast condensation in the Ruyang acritarchs was an in vivo biologically programmed response to adverse conditions in preparation for encystment. While the discovery of bona fide nuclei in Paleoproterozoic acritarchs would be a substantial landmark in our understanding of eukaryote evolution, the various processes (such as degradational and biological condensation of protoplasts) capable of producing nuclei-mimicking structures require that interpretation of ICIs as fossilized nuclei be based on comprehensive investigations.
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Yang Z, Ding J, Yang C, Gao Y, Li X, Chen X, Peng Y, Fang J, Xiao S. Immunomodulatory and anti-inflammatory properties of artesunate in experimental colitis. Curr Med Chem 2013; 19:4541-51. [PMID: 22834815 DOI: 10.2174/092986712803251575] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 06/27/2012] [Accepted: 07/11/2012] [Indexed: 11/22/2022]
Abstract
BACKGROUND Inflammatory bowel disease is a chronic and idiopathic gastrointestinal inflammation mediated by disregulated immune responses. Artemisinin (a chemical from a traditional Chinese herbal medicine Artemisia annua L.) and its derivatives have been proven to exhibit anti-inflammatory and immunomodulatory effects in the treatment of systemic lupus erythematosus and rheumatoid arthritis with low side-effects. This study is aimed to evaluate the potential therapeutic value of artesunate for inflammatory bowel disease. METHODS Murine colitis was induced by either oral administration of dextran sulfate sodium salt (DSS) or intrarectal delivery of 2,4,6- trinitrobenzene sulfonic acid (TNBS) or oxazolone. Mice were treated with artesunate (150mg/kg/day). Peritoneal macrophages were stimulated with lipopolysaccharide (LPS) in the presence or absence of artesunate. Changes in cytokines or proteins of interests were analyzed by enzyme-linked immunosorbent assay (ELISA) or SDS-PAGE/Western blot. RESULTS Artesunate significantly ameliorated DSS colitis and TNBS colitis (but not oxazolone colitis), including reduced weight loss and disease activity, as well as macroscopic and microscopic colonic injury. The expression of NF-κBp65 and p-IκB-α were reduced in artesunate treated TNBS colitis compared with untreated. The levels of IFN-γ, IL-17, and TNF-α were significantly decreased in artesunate treated TNBS colitis or DSS colitis. Furthermore, in vitro artesunate treatment significantly inhibited TNF-α production by LPS-activated macrophages. CONCLUSIONS Artesunate suppresses TNF-α expression in vitro and in vivo as well as T-helper (Th)1/Th17 responses in TNBS colitis model. Our data suggest a novel clinical application of artesunate as a potential therapy for Crohn's disease.
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Ganapathy S, Xiao S, Seo SJ, Lall R, Yang M, Xu T, Su H, Shadfan M, Ha CS, Yuan ZM. Low-dose arsenic induces chemotherapy protection via p53/NF-κB-mediated metabolic regulation. Oncogene 2013; 33:1359-66. [PMID: 23524579 PMCID: PMC4467814 DOI: 10.1038/onc.2013.81] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 01/02/2013] [Accepted: 01/11/2013] [Indexed: 02/08/2023]
Abstract
Most chemotherapeutical drugs kill cancer cells chiefly by inducing DNA damage, which unfortunately also causes undesirable injuries to normal tissues, mainly due to p53 activation. We report a novel strategy of normal tissue-protection that involves p53/NF-κB coordinated metabolic regulation. Pretreatment of untransformed cells with low doses of arsenic induced concerted p53 suppression and NF-κB activation, which elicited a marked induction of glycolysis. Significantly, this metabolic shift provided cells effective protection against cytotoxic chemotherapy, coupling the metabolic pathway to cellular resistance. Using both in vitro and in vivo models, we demonstrated an absolute requirement of functional p53 in arsenic-mediated protection. Consistently, a brief arsenic-pretreatment selectively protected only normal tissues but not tumors from toxicity of chemotherapy. An indispensable role of glycolysis in protecting normal tissues was demonstrated by using an inhibitor of glycolysis, 2-deoxyglucose, which almost totally abolished low-dose arsenic-mediated protection. Together, our work demonstrates that low-dose arsenic renders normal cells and tissues resistance to chemotherapy-induced toxicity by inducting glycolysis.
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Butterfield BJ, Cavieres LA, Callaway RM, Cook BJ, Kikvidze Z, Lortie CJ, Michalet R, Pugnaire FI, Schöb C, Xiao S, Zaitchek B, Anthelme F, Björk RG, Dickinson K, Gavilán R, Kanka R, Maalouf JP, Noroozi J, Parajuli R, Phoenix GK, Reid A, Ridenour W, Rixen C, Wipf S, Zhao L, Brooker RW. Alpine cushion plants inhibit the loss of phylogenetic diversity in severe environments. Ecol Lett 2013; 16:478-86. [DOI: 10.1111/ele.12070] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 09/04/2012] [Accepted: 12/08/2012] [Indexed: 11/28/2022]
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Guo X, Ding X, Lei M, Xie M, Zhong L, Xiao S. Non-invasive monitoring and evaluating cardiac function of pregnant women based on a relative value method. ACTA ACUST UNITED AC 2012; 99:382-91. [DOI: 10.1556/aphysiol.99.2012.4.2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Deng Z, Xiao S, Huang S, Gmitter FG. Development and characterization of SCAR markers linked to the citrus tristeza virus resistance gene from Poncirus trifoliata. Genome 2012; 40:697-704. [PMID: 18464859 DOI: 10.1139/g97-792] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Twelve new dominant randomly amplified polymorphic DNA (RAPD) fragments associated with a single dominant gene for resistance to citrus tristeza virus (CTV) were identified using bulked segregant analysis of an intergeneric backcross family. These and eight previously reported RAPDs were mapped in the resistance gene (Ctv) region; the resulting localized linkage map spans about 32 cM, with nine close flanking markers within 2.5 cM of Ctv. Seven of 20 RAPD fragments linked with the resistance gene were cloned and sequenced, and their sequences were used to design longer primers to develop sequence characterized amplified region (SCAR) markers that can be utilized reliably in marker-assisted selection, high-resolution mapping, and map-based cloning of the resistance gene. All seven cloned RAPDs were converted successfully into SCARs by redesigning primers, optimizing PCR parameters (especially the annealing temperature), or digesting amplification products with restriction enzymes. Four of the seven remained dominant markers, displaying presence-absence polymorphism patterns; the other three detected restriction site changes or length variations and thus were transformed into codominant markers. Two genomic regions rich in variability were also detected by two codominant SCAR markers.
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Schiffbauer JD, Wallace AF, Hunter JL, Kowalewski M, Bodnar RJ, Xiao S. Thermally-induced structural and chemical alteration of organic-walled microfossils: an experimental approach to understanding fossil preservation in metasediments. GEOBIOLOGY 2012; 10:402-423. [PMID: 22607551 DOI: 10.1111/j.1472-4669.2012.00332.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The identification and confirmation of bona fide Archean-Paleoproterozoic microfossils can prove to be a challenging task, further compounded by diagenetic and metamorphic histories. While structures of likely biological origin are not uncommon in Precambrian rocks, the search for early fossil life has been disproportionately focused on lesser thermally altered rocks, typically greenschist or lower-grade metamorphism. Recently, however, an increasing number of inferred micro- and macrofossils have been reported from higher-grade metasediments, prompting us to experimentally test and quantify the preservability of organic-walled microfossils over varying durations of controlled heating and under two differing redox conditions. Because of their relatively low-intensity natural thermal alteration, acritarchs from the Mesoproterozoic Ruyang Group were chosen as subjects for experimental heating at approximately 500°C, with durations ranging from 1 to 250 days and in both oxic (normal present day conditions) and anoxic conditions. Upon extraction, the opacity, reflectivity, color, microchemistry, and microstructures of the heated acritarchs were characterized using optic microscopy, scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The results differ for acritarchs prepared under oxic vs. anoxic conditions, with the anoxic replicates surviving experimental heating longer and retaining biological morphologies better, despite an increasing degree of carbonization with continuous heating. Conversely, the oxic replicates show aggressive degradation. In conjunction with fossils from high-grade metasediments, our data illustrate the preservational potential of organic-walled microfossils subjected to metamorphism in reducing conditions, offer insights into the search for microfossils in metasediments, and help to elucidate the influence of time on the carbonization/graphitization processes during thermal alteration.
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Toscano G, Raza S, Xiao S, Wubs M, Jauho AP, Bozhevolnyi SI, Mortensen NA. Surface-enhanced Raman spectroscopy: nonlocal limitations. OPTICS LETTERS 2012; 37:2538-2540. [PMID: 22743447 DOI: 10.1364/ol.37.002538] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Giant field enhancement and field singularities are a natural consequence of the commonly employed local-response framework. We show that a more general nonlocal treatment of the plasmonic response leads to new and possibly fundamental limitations on field enhancement with important consequences for our understanding of surface-enhanced Raman spectroscopy (SERS). The intrinsic length scale of the electron gas serves to smear out assumed field singularities, leaving the SERS enhancement factor finite, even for geometries with infinitely sharp features. For silver nanogroove structures, mimicked by periodic arrays of half-cylinders (up to 120 nm in radius), we find no enhancement factors exceeding 10 orders of magnitude (10(10)).
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Li X, Zhang D, Xiao S, Peng Z. Four novel mutations of the ATP2C1 gene in Chinese patients are associated with familial benign chronic pemphigus. Clin Exp Dermatol 2012; 37:797-9. [PMID: 22607350 DOI: 10.1111/j.1365-2230.2012.04364.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Xiao S, Baker C, Oyewumi LK. Psychosocial processes influencing weight management among persons newly prescribed atypical antipsychotic medications. J Psychiatr Ment Health Nurs 2012; 19:241-7. [PMID: 22074295 DOI: 10.1111/j.1365-2850.2011.01773.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The purpose was to generate a theory of the psychosocial processes influencing weight management among persons newly prescribed atypical antipsychotic medications. A grounded theory research design was used to guide the study. Semi-structured interviews were the method of data collection, and analysis was performed using constant comparison. Using theoretical sampling, a sample of 11 participants with first-episode psychosis prescribed atypical antipsychotics for at least 8 weeks, and five participants with a diagnosis of chronic schizophrenia prescribed atypical antipsychotic medication for at least 3 years were recruited from an outpatient psychiatric programme. Contextual factors influencing weight management were: accessibility to resources, unstructured lifestyle, and others' perception of weight. Conditions influencing weight management were: rapid weight gain, insatiable hunger and lack of motivation boosters. Participants' early responses to weight gain included discontinuing medications, choosing lower-calorie foods, using walking in daily activities as exercise, accepting weight gain and trying to manage weight but giving up. The consequences revealed from data analysis were contemplating weight management and not trying, as the barriers to weight management exceeded the facilitators. The theoretical framework developed in this study can assist with the understanding and management of weight gain among this unique population.
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Zhou H, Liu Z, Liu J, Wang J, Zhou D, Zhao Z, Xiao S, Tao E, Suo WZ. Fractionated radiation-induced acute encephalopathy in a young rat model: cognitive dysfunction and histologic findings. AJNR Am J Neuroradiol 2011; 32:1795-800. [PMID: 21920857 DOI: 10.3174/ajnr.a2643] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Radiation-induced cognitive dysfunction is a common and serious complication after radiation therapy of brain tumor, yet knowledge of its mechanism is poorly understood. The aim of this study was to establish a young rat model for acute radiation encephalopathy, at both cognitive and pathologic levels, induced by fractionated irradiation. MATERIALS AND METHODS Four-week-old male rats were randomized into sham (0 Gy) and 2 experimental groups receiving fractionated irradiation of 5 Gy/day, 5 days/week, with total doses of 20 and 40 Gy, respectively. Cognition, BBB integrity, and potential astrogliosis were evaluated at 0, 4, 8, and 12 weeks' postirradiation. RESULTS Twenty-Gy irradiation led to transient cognitive impairment only at 4 weeks' postirradiation. Forty-Gy irradiation induced cognitive impairment at both 4 and 8 weeks' postirradiation, which was more severe than that induced by 20 Gy. Cognitive impairment was accompanied by a transient increase in BWC only at 4 weeks for the 40-Gy group. Disrupted BBB permeability was detected at 4 and 8 weeks' postirradiation for the 20-Gy group, and at 4, 8, and 12 weeks' postirradiation for 40-Gy group, respectively. Increased astrogliosis in the hippocampus could be detected at 4 weeks' postirradiation for 40-Gy group. CONCLUSIONS Fractionated irradiation in this experiment could induce acute brain injury, leading to cognitive impairment in young rats. BBB disruption might be a sensitive index for acute radiation encephalopathy. In addition, reactive astrogliosis might play an important role in this process. The present model, especially the 40-Gy irradiation group, is useful for basic and therapeutic studies of acute radiation encephalopathy.
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