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Chen XF, Zhang HL, Chen J. First Report of Dickeya solani Causing Soft Rot in Imported Bulbs of Hyacinthus orientalis in China. PLANT DISEASE 2015; 99:155. [PMID: 30699774 DOI: 10.1094/pdis-09-14-0916-pdn] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A bacterial pathogen, Dickeya solani, emerged as a major threat to potato (Solanum tuberosum) production in Europe in 2004 and has spread to many potato-growing regions via international trade. In December 2013, soft rot symptoms were observed in hyacinth (Hyacinthus orientalis) bulbs imported from the Netherlands into China at Ningbo Port. Diseased bulbs gave off an offensive odor. The base and internal parts of diseased bulbs rotted, and the margins of diseased tissues showed brown discoloration. Isolation on nutrient agar glucose (NAG) medium resulted in dominating colonies of characteristic "fried egg" morphology (1). One colony was chosen for further investigation and tentatively named "isolate 6165-3." Under microscopic visualization after gram stain, the cells of isolate 6165-3 were gram-negative, motile, and rod shaped. The isolate was then identified as a member of genus Dickeya using the Biolog GN microplate. The 16S rRNA, recA, and dnaX sequences of isolate 6165-3 were subsequently determined and deposited in GenBank with accession numbers KM405240, KM405241, and KM405242, sharing 99% (16S rRNA), 100% (recA), and 100% (dnaX) nucleotide identity with those of known D. solani isolates, respectively. By this means, the isolate 6165-3 was identified as D. solani (1,2). To confirm the pathogenicity of the isolate, four plants each of 30-day-old hyacinth, 14-day-old potato, and 60-day-old moth orchid (Phalaenopsis amabilis) were inoculated with suspensions of the isolate with a concentration of 108 CFU/ml in sterile water by stabbing. Plants were incubated in a climate chamber at 28°C during the day and 24°C during the night with a relative humidity of 93% and a photoperiod of 12/12 h. Plants inoculated with sterile water were included as negative controls. After 2 or 3 days, typical symptoms such as water-soaked lesions and soft rot developed around the inoculation point, while the negative controls remained symptomless. Koch's postulates were fulfilled by re-isolating bacteria from lesions, which had identical sequence and morphology characters with the inoculated isolate. This is the first report of intercepted D. solani on hyacinth bulbs imported from the Netherlands into China, indicating that D. solani can spread via hyacinth. Further spread of the pathogen into potato production might lead to immeasurable economic consequences for China. References: (1) P. F. Sarris et al. New Dis. Rep. 24:21, 2011. (2) J. M. van der Wolf et al. Int. J. Syst. Evol. Microbiol. 64:768, 2014.
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Liang W, Zhang HL, Liu Y, Lu BC, Liu X, Li Q, Cao Y. Investigation of the association of two candidate genes (H-FABP and PSMC1) with growth and carcass traits in Qinchuan beef cattle from China. GENETICS AND MOLECULAR RESEARCH 2014; 13:1876-84. [PMID: 24668675 DOI: 10.4238/2014.march.17.15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Growth and carcass traits are economically important quality characteristics of beef cattle and are complex quantitative traits that are controlled by multiple genes. In this study, 2 candidate genes, H-FABP (encoding the heart fatty acid-binding protein) and PSMC1 (encoding the proteasome 26S subunit of ATPase 1) were investigated in Qinchuan beef cattle of China. PCR-SSCP and DNA sequencing methods were used to detect mutations in the H-FABP and PSMC1 genes in Qinchuan cattle, and a T>C mutation in exon 1 of H-FABP and a T>C mutation in exon 9 of PSMC1 were identified. The association of these 2 single nucleotide polymorphisms with growth and carcass traits of Qinchuan cattle was analyzed. The T>C mutation in H-FABP was significantly associated with body length and dressing percentage (P < 0.05) and the T>C mutation in PSMC1 with body length and hip width (P < 0.05), indicating that both of the 2 mutations in H-FABP and PSMC1 had effects on growth and carcass traits in the Qinchuan beef cattle breed. Thus, the results of our study suggest that the H-FABP and PSMC1 gene polymorphisms could be used as genetic markers in marker-assisted selection for improving Qinchuan beef cattle.
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Zhou ZL, Lin SQ, Yang HY, Zhang HL, Xia JM. Antiviral Constituents from the Bulbs of Lilium lancifolium. ACTA ACUST UNITED AC 2014. [DOI: 10.14233/ajchem.2014.16978] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Punkkinen MPJ, Kokko K, Levämäki H, Ropo M, Lu S, Delczeg L, Zhang HL, Delczeg-Czirjak EK, Johansson B, Vitos L. Adhesion of the iron-chromium oxide interface from first-principles theory. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:495501. [PMID: 24184730 DOI: 10.1088/0953-8984/25/49/495501] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We determine the interface energy and the work of separation of the Fe/Cr2O3 interface using first-principles density functional theory. Starting from different structures, we put forward a realistic interface model that is suitable to study the complex metal-oxide interaction. This model has the lowest formation energy and corresponds to an interface between Fe and oxygen terminated Cr2O3. The work of separation is calculated to be smaller than the intrinsic adhesion energy of pure Fe or Cr2O3, suggesting that stainless steel surfaces should preferentially break along the metal-oxide interface. The relative stabilities and magnetic interactions of the different interfaces are discussed. Next we introduce Cr atoms into the Fe matrix at different positions relative to the interface. We find that metallic Cr segregates very strongly to the (FeCr)/Cr2O3 interface, and increases the separation energy of the interface, making the adhesion of the oxide scale mechanically more stable. The Cr segregation is explained by the enthalpy of formation.
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Zhao MX, Yu KF, Shi Q, Chen TR, Zhang HL, Chen TG. Coral communities of the remote atoll reefs in the Nansha Islands, southern South China Sea. ENVIRONMENTAL MONITORING AND ASSESSMENT 2013; 185:7381-7392. [PMID: 23355025 DOI: 10.1007/s10661-013-3107-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Accepted: 01/16/2013] [Indexed: 06/01/2023]
Abstract
During the months of May and June in the year 2007, a survey was conducted regarding coral reef communities in the remote atolls (Zhubi Reef and Meiji Reef) of Nansha Islands, southern South China Sea. The goals of the survey were to: (1) for the first time, compile a scleractinian coral check-list; (2) estimate the total richness, coral cover, and growth forms of the community; and (3) describe preliminary patterns of community structure according to geomorphological units. Findings of this survey revealed a total of 120 species of scleractinia belonging to 40 genera, while the average coral cover was 21 %, ranging from less than 10 % to higher than 50 %. Branching and massive corals were also found to be the most important growth forms of the whole coral community, while Acropora, Montipora, and Porites were the three dominant genera in the overall region, with their contributions to total coral cover measuring 21, 22, and 23 %, respectively. Overall, coral communities of the Nansha Islands were in a relative healthy condition with high species diversity and coral cover. Spatial pattern of coral communities existed among various geomorphological units. Mean coral cover was highest in the patch reef within the lagoon, followed by the fore reef slope, reef flat, and lagoon slope. The greatest contributors to total coral cover were branching Acropora (45 %) in the lagoon slope, branching Montipora (44 %) in the reef flat, and massive Porites (51 %) in the patch reef. Coral cover in the fore reef revealed a greater range of genera than in other habitats. The leeward fore reef slope had higher coral cover (> 50 %) when compared with the windward slope (< 10 %). The coral communities of the inner reef flat were characterized by higher coral cover (27 %) and dominant branching Montipora corals, while lower coral cover (4 %) was dominated by Psammocora with massive growth forms on the outer reef flat. Destructive fishing and coral bleaching were two major threats to coral communities in the study area.
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Zhang F, Mi Y, Qi JL, Li JW, Si M, Guan BC, Du XN, An HL, Zhang HL. Modulation of K(v)7 potassium channels by a novel opener pyrazolo[1,5-a]pyrimidin-7(4H)-one compound QO-58. Br J Pharmacol 2013; 168:1030-42. [PMID: 23013484 DOI: 10.1111/j.1476-5381.2012.02232.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 08/22/2012] [Accepted: 09/17/2012] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND AND PURPOSE Modulation of K(v)7/M channel function represents a relatively new strategy to treat neuronal excitability disorders such as epilepsy and neuropathic pain. We designed and synthesized a novel series of pyrazolo[1,5-a] pyrimidin-7(4H)-one compounds, which activate K(v)7 channels. Here, we characterized the effects of the lead compound, QO-58, on K(v)7 channels and investigated its mechanism of action. EXPERIMENTAL APPROACH A perforated whole-cell patch technique was used to record K(v)7 currents expressed in mammalian cell lines and M-type currents from rat dorsal root ganglion neurons. The effects of QO-58 in a rat model of neuropathic pain, chronic constriction injury (CCI) of the sciatic nerve, were also examined. KEY RESULTS QO-58 increased the current amplitudes, shifted the voltage-dependent activation curve in a more negative direction and slowed the deactivation of K(v)7.2/K(v)7.3 currents. QO-58 activated K(v)7.1, K(v)7.2, K(v)7.4 and K(v)7.3/K(v)7.5 channels with a more selective effect on K(v)7.2 and K(v)7.4, but little effect on K(v)7.3. The mechanism of QO-58's activation of K(v)7 channels was clearly distinct from that used by retigabine. A chain of amino acids, Val(224)Val(225)Tyr(226), in K(v)7.2 was important for QO-58 activation of this channel. QO-58 enhanced native neuronal M currents, resulting in depression of evoked action potentials. QO-58 also elevated the pain threshold of neuropathic pain in the sciatic nerve CCI model. CONCLUSIONS AND IMPLICATIONS The results indicate that QO-58 is a potent modulator of K(v)7 channels with a mechanism of action different from those of known K(v)7 openers. Hence, QO-58 shows potential as a treatment for diseases associated with neuronal hyperexcitability.
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Gumberidze A, Thorn DB, Fontes CJ, Najjari B, Zhang HL, Surzhykov A, Voitkiv A, Fritzsche S, Banaś D, Beyer H, Chen W, DuBois RD, Geyer S, Grisenti RE, Hagmann S, Hegewald M, Hess S, Kozhuharov C, Märtin R, Orban I, Petridis N, Reuschl R, Simon A, Spillmann U, Trassinelli M, Trotsenko S, Weber G, Winters DFA, Winters N, Yu D, Stöhlker T. Electron- and proton-impact excitation of hydrogenlike uranium in relativistic collisions. PHYSICAL REVIEW LETTERS 2013; 110:213201. [PMID: 23745869 DOI: 10.1103/physrevlett.110.213201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Indexed: 06/02/2023]
Abstract
The K shell excitation of H-like uranium (U(91+)) in relativistic collisions with different gaseous targets has been studied at the experimental storage ring at GSI Darmstadt. By performing measurements with different targets as well as with different collision energies, we were able to observe for the first time the effect of electron-impact excitation (EIE) process in the heaviest hydrogenlike ion. The large fine-structure splitting in H-like uranium allowed us to unambiguously resolve excitation into different L shell levels. State-of-the-art calculations performed within the relativistic framework which include excitation mechanisms due to both protons (nucleus) and electrons are in good agreement with the experimental findings. Moreover, our experimental data clearly demonstrate the importance of including the generalized Breit interaction in the treatment of the EIE process.
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Zhang HL, Fan HJ, Liu XL, Wu Y, Hou SS. Molecular cloning of the perilipin gene and its association with carcass and fat traits in Chinese ducks. GENETICS AND MOLECULAR RESEARCH 2013; 12:1582-92. [PMID: 23765965 DOI: 10.4238/2013.may.13.12] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The perilipin (PLIN) gene is a candidate gene of carcass and fat traits in ducks. In order to study the molecular character of the PLIN gene and its function in different breeds of Chinese ducks, samples were obtained from the Chinese Academy of Agricultural Sciences Research Center for Birds, including 95 Peking ducks of the Z2 series, 91 Peking ducks of the Z4 series, 82 hybrid systems (Z2 x Z4), and 93 Cherry Valley ducks. We used RT-PCR and 3'-RACE to clone the duck PLIN gene, detect SNPs and analyze their associations with carcass and fat traits. A 2212-bp sequence was cloned with the complete coding region and a 3'-untranslated region. We found a nucleotide mutation (C → T) in exon 2 of the PLIN gene. There were no significant correlations between the 3 genotypes (CC, CT, TT) in breast muscle weight (BMW), leg muscle weight (LMW), subcutaneous fat weight (SFW), and intramuscular fat (IMF) in the Cherry Valley duck. The CC and CT genotypes had significant differences in carcass weight (CW), carcass net weight (CNW), and percentage of abdominal fat weight (AFW); there were significant differences in AFW and percentage of SFW. In Z4, there were no significant correlations between the 3 genotypes (TT, CC, and CT) in CW, BMW, LMW, SFW, AFW, the percentage of SFW and AFW, and IMF. CNW was significantly different between TT, CC, and CT genotypes. In Z2 x Z4, there were no significant correlations between the 3 genotypes in CW, BMW, LMW, SFW, AFW, the percentage of SFW and AFW, and IMF, while the CC and CT genotypes had significant differences in CNW. In Z2, there were no significant differences between the 3 genotypes in all traits. We deduced that the PLIN gene is a potential major gene. It is linked to a major gene affecting meat quality traits. This SNP has potential as a molecular marker for marker-assisted selection.
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Zhou ZL, Feng ZC, Fu CY, Zhang HL, Xia JM. Steroidal and phenolic glycosides from the bulbs of Lilium pumilum DC and their potential Na+/K+ ATPase inhibitory activity. Molecules 2012; 17:10494-502. [PMID: 22945028 PMCID: PMC6268628 DOI: 10.3390/molecules170910494] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 08/25/2012] [Accepted: 08/29/2012] [Indexed: 11/21/2022] Open
Abstract
A new steroidal saponin, named pumilum A (1), and a new phenolic glycoside, threo-1-(4′-hydroxy-2′-methoxyphenyl)-2-(2′′,4′′-dihydroxyphenyl)-1,3-propanediol-4′-O-β-D-glucopyranoside (7) were isolated from the methanolic extract of the bulbs of Lilium pumilum DC, along with five known steroidal saponins. Their chemical structures were elucidated on the basis of detailed spectroscopic analysis, including 1D and 2D NMR techniques and chemical methods. In addition, the inhibitory activity of all the isolates on Na+/K+ ATPase was evaluated.
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Zhu Y, Hong YP, Zhang HL, Shi GH, Xiao WJ, Wang ZH, Yao XD, Zhang SL, Dai B, Ye DW. Conditional survival in patients treated with vascular endothelial growth factor-targeted therapy for advanced renal cell carcinoma. J Cancer Res Clin Oncol 2012; 138:1901-7. [PMID: 22744643 DOI: 10.1007/s00432-012-1266-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 06/05/2012] [Indexed: 11/25/2022]
Abstract
PURPOSE Conditional survival (CS) offers more relevant prognostic information for patients once they have survived for some time. The objective of this study was to determine the CS for advanced renal cell carcinoma (RCC) patients treated with vascular endothelial growth factor-targeted therapy. METHODS A total of 345 patients treated between 2006 and 2011 fulfilled the inclusion criteria and were reviewed for analyses. The 1-year conditional and actual survival rates were calculated for survivors from treatment to month 24. Subgroup-specific CS rates were generated after adjustment of the covariate influence. The Cox proportional hazard models were used to assess the prognostic factors at baseline and 1-year landmark. RESULTS The probabilities of surviving an additional year given survival to 6, 12, 18, and 24 months were 72.2, 76.3, 78.2, and 78.6 %, respectively. Remarkable increase in CS was observed in patients initially classified as intermediate or poor risk according to Heng risk groups. For patients survived 24 months after treatment, the adjusted CS for the following year was over 80 % regardless of initial risk attribution. Compared to baseline analysis, Heng risk groups were less predictive of survivorship after surviving 1 year. The addition of disease control status to multifactorial model significantly improved survival estimation for 1-year survivors (p < 0.01). CONCLUSIONS CS provides useful information regarding life expectancy for survivors of advanced RCC treated with targeted therapy. Furthermore, disease control status within a specific period of time is critical to the prediction of subsequent survival.
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Du XN, Zhang X, Qi JL, An HL, Li JW, Wan YM, Fu Y, Gao HX, Gao ZB, Zhan Y, Zhang HL. Characteristics and molecular basis of celecoxib modulation on K(v)7 potassium channels. Br J Pharmacol 2012; 164:1722-37. [PMID: 21564087 DOI: 10.1111/j.1476-5381.2011.01483.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND PURPOSE Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor used for the treatment of pain and inflammation. Emerging and accumulating evidence suggests that celecoxib can affect cellular targets other than COX, such as ion channels. In this study, we characterized the effects of celecoxib on K(v)7 K(+) channels and compared its effects with the well-established K(v)7 channel opener retigabine. EXPERIMENTAL APPROACH A perforated whole-cell patch technique was used to record K(v)7currents expressed in HEK 293 cells and M-type currents from rat superior cervical ganglion neurons. KEY RESULTS Celecoxib enhanced K(v)7.2-7.4, K(v)7.2/7.3 and K(v)7.3/7.5 currents but inhibited K(v)7.1 and K(v)7.1/KCNE1 currents and these effects were concentration dependent. The IC(50) value for inhibition of K(v)7.1 channels was approximately 4 µM and the EC(50) values for activation of K(v)7.2-7.4, K(v)7.2/K(v)7.3 and K(v)7.3/K(v)7.5 channels were approximately 2-5 µM. The effects of celecoxib were manifested by increasing current amplitudes, shifting the voltage-dependent activation curve in a more negative direction and slowing the deactivation of K(v)7 currents. 2,5-Dimethyl-celecoxib, a celecoxib analogue devoid of COX inhibition activity, has similar but greater effects on K(v)7currents. K(v)7.2(A235T) and K(v) 7.2(W236L) mutant channels, which have greatly attenuated responses to retigabine, showed a reversed response to celecoxib, from activation to inhibition. CONCLUSIONS AND IMPLICATIONS These results suggest that K(v)7 channels are targets of celecoxib action and provide new mechanistic evidence for understanding the effects of celecoxib. They also provide a new approach to developing K(v)7 modulators and for studying the structure-function relationship of K(v)7 channels.
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Zhang HL, Yu JY, Feng ZG, Xue LH, Wu SP. Effect of aging on the morphology of bitumen by atomic force microscopy. J Microsc 2011; 246:11-9. [PMID: 22171593 DOI: 10.1111/j.1365-2818.2011.03578.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Yang YC, Zhang HL, Zhou ZH. Ketopiperazinediacetate zinc and copper complexes in the degradation of ethylenediaminetriaceta. INORG CHEM COMMUN 2011. [DOI: 10.1016/j.inoche.2011.03.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Xiao Y, Zhang HL, Bai LY, Wang XM, Li WG, Yang LG. [Active DNA demethylation in mammals]. YI CHUAN = HEREDITAS 2011; 33:298-306. [PMID: 21482518 DOI: 10.3724/sp.j.1005.2011.00298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
DNA methylation is a stable and heritable epigenetic mark, and it is one of the best characterized epigenetic modifications. Active DNA demethylation has been reported both in plant and animal cells, and the mechanism behind it is becoming clear in plant. Whereas a bona fide enzyme, which is responsible for active DNA demethylation, have not been identified in mammals, and active demethylation pathway is controversial. In the present review, we described that active DNA demethylation take place in a spatial- and temporal-specific way on the basis of recent literatures. Moreover, several candidate pathways such as oxygenation and deamination of 5-methyl cytosine and DNA repair pathways, which may be responsible for the active process were introduced on a cell- and tissue-specific view. The aim of this paper is to help re-searchers reveal the mechanism underlying this important event during epigenetic reprogramming in mammals.
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Su ZQ, Wu SH, Zhang HL, Feng YF. Development and validation of an improved Bradford method for determination of insulin from chitosan nanoparticulate systems. PHARMACEUTICAL BIOLOGY 2010; 48:966-973. [PMID: 20731546 DOI: 10.3109/13880200903325615] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
CONTEXT Blank chitosan nanoparticles are currently used as reference for the calibration curve, which fails to resolve the supernatant of the nanoparticles in the interference of Coomassie Brilliant Blue G-250 reagent; supernatants are generated at different chitosan nanoparticulate prescriptions, which have different interferences. There are notable errors in the experimental results, and the method is not feasible. OBJECTIVE In this study, an improved, rapid, and economic Bradford method was developed and validated. MATERIALS AND METHODS The pH of the supernatant of blank chitosan nanoparticles was adjusted to 7-9 through adding saturated NaOH. The precipitation (free chitosan) in the solution was separated by centrifuging for about 10 min (4000 r/min). RESULTS The method eliminated the interference of free chitosan of different prescriptions. The results showed that the method presented a linearity in the range of 50-300 microg/mL (R(2) = 0.9992), and possessed a good inter-day and intra-day precision based on relative standard deviation values (less than 3.10%). Recovery of the supernatant of blank chitosan nanoparticles was between 98.30 and 99.93%, and the recovery of blank chitosan nanoparticles was between 95.57 and 100.27%. DISCUSSION AND CONCLUSION The method was further tested for determination of the association efficiency of insulin to nanoparticulate carriers composed of chitosan. Encapsulant release under simulated gastrointestinal fluids was evaluated.
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Zhang HL, Wang HC, Yu JY. Effect of aging on morphology of organo-montmorillonite modified bitumen by atomic force microscopy. J Microsc 2010; 242:37-45. [PMID: 21118229 DOI: 10.1111/j.1365-2818.2010.03435.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The morphology of unmodified and organo-montmorillonite modified bitumens was investigated by atomic force microscopy. The influence of thin film oven test and ultraviolet aging on the morphology of the binders was also analysed. The atomic force microscopy results showed that bitumen displayed a 'bee-like' structure and the dimension of the 'bee-like' structures was decreased to some extent with the introduction of organo-montmorillonite. Organo-montmorillonite showed a better interaction with the dispersed domains in comparison with the matrix in bitumen, which led to an obvious increase in the contrast between the dispersed domains and the matrix in bitumen. Compared with the unmodified bitumen, the single-phase trend in the organo-montmorillonite modified bitumen could be effectively prevented during thin film oven test and ultraviolet aging, indicating its good aging resistance which was in accordance with changes in physical properties of the organo-montmorillonite modified bitumen before and after aging.
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Pradhan AK, Nahar SN, Montenegro M, Yu Y, Zhang HL, Sur C, Mrozik M, Pitzer RM. Resonant X-ray enhancement of the Auger effect in high-Z atoms, molecules, and nanoparticles: potential biomedical applications. J Phys Chem A 2010; 113:12356-63. [PMID: 19888772 DOI: 10.1021/jp904977z] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
It is shown that X-ray absorption can be considerably enhanced at resonant energies corresponding to K-shell excitation into higher shells with electron vacancies following Auger emissions in high-Z elements and compounds employed in biomedical applications. We calculate Auger resonant probabilities and cross sections to obtain total mass attenuation coefficients with resonant cross sections and detailed resonance structures corresponding to Kalpha, Kbeta, Kgamma, Kdelta, and Keta complexes lying between 6.4-7.1 keV in iron and 67-80 keV in gold. The basic parameters were computed using the relativistic atomic structure codes and the R-matrix codes. It is found that the average enhancement at resonant energies is up to a factor of 1000 or more for associated K --> L, M, N, O, P transitions. The resonant energies in high-Z elements such as gold are sufficiently high to ensure significant penetration in body tissue, and hence the possibility of achieving X-radiation dose reduction commensurate with resonant enhancements for cancer theranostics using high-Z nanoparticles and molecular radiosensitizing agents embedded in malignant tumors. The in situ deposition of X-ray energy, followed by secondary photon and electron emission, will be localized at the tumor site. We also note the relevance of this work to the development of novel monochromatic or narrow-band X-ray emission sources for medical diagnostics and therapeutics.
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Zhang RH, Hong QM, Yang JM, Zhang HL, Michael Blackburnb G, Zhou ZH. Syntheses, spectroscopies and structures of zinc complexes with malate. Inorganica Chim Acta 2009. [DOI: 10.1016/j.ica.2008.12.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Liu LX, Song CN, Song LP, Zhang HL, Dong X, Leng XG. Effects of alkylated-chitosan-DNA nanoparticles on the function of macrophages. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:943-948. [PMID: 19020960 DOI: 10.1007/s10856-008-3621-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 10/09/2008] [Indexed: 05/27/2023]
Abstract
Chitosan could form nanoparticles with DNA through electrostatic interaction, and hence protect the DNA from enzymatic degradation. Numerous studies have been working on modifying chitosan aiming at improving its transgenic efficacy. While the modification of chitosan with alkyl group has been shown to significantly improve the cell transfection efficiency, little is known about its impact on its biocompatibility. The current study was performed to investigate the impact of alkylated-chitosan/DNA nanoparticles on the function of the murine macrophage through observing its phagocytic activity and production of pro-inflammatory cytokines (IL-1beta, IL-6, IL-10, IL-12 and TNF-alpha). Our results demonstrated that the alkylated-chitosan/DNA nanoparticles at the concentration of 20 microg/ml DNA content had no significant impact on the production of cytokines and phagocytic activity of the macrophages as compared with the unmodified chitosan/DNA nanoparticles and negative control even after 24 h co-incubation. It suggested that the modification of chitosan with alkyl group should not have negative impact on the function of the macrophages.
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Wang Y, Liu YQ, Li XL, Cao LC, Wei DC, Zhang HL, Shi DC, Yu G. Large-scale growth and characteristics of N-doped carbon nanotubes with ultra-large cavity. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:1076-1079. [PMID: 19441459 DOI: 10.1166/jnn.2009.c091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
N-doped carbon nanotubes (CNTs) with ultra-large cavity have been synthesized by using a mixture of ZnO and graphite as catalyst in the floating catalyst method. The as-synthesized N-doped CNTs are very pure, and a striking characteristic structure is that the outer diameter is at least 10 times larger than the wall thickness. Moreover, electronic properties analysis reveals that the N-doped CNTs with ultra-large cavity have a reduced room temperature resistance compared with those of the common N-doped CNTs, which give an experimental prove for the previous theoretical predictions.
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Wang MX, Zhang HL, Zhang DL, Qi YW, Fan ZL, Li DY, Pan DJ, Cao YS, Qiu ZE, Yu P, Yang QW, Wang XK, Li ZC. Genetic structure of Oryza rufipogon Griff. in China. Heredity (Edinb) 2008; 101:527-35. [PMID: 18827837 DOI: 10.1038/hdy.2008.61] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Oryza rufipogon Griff. (common wild rice; CWR) is the ancestor of Asian cultivated rice (Oryza sativa L.). Investigation of the genetic structure and diversity of CWR in China will provide information about the origin of cultivated rice and the grain quality and yield. In this study, we used 36 simple sequence repeat (SSR) markers to assay 889 accessions, which were highly representative of whole germplasm in China. The analysis revealed a hierarchical genetic structure within CWR. First, CWR has diverged into two ecotypic populations, a south subtropical population (SSP) and a middle subtropical population (MSP), probably owing to natural selection by the different climates. The distribution of specific alleles and haplotypes indicated that Chinese CWR had both indica-like and japonica-like variations; the SSP was an indica-like type, whereas the MSP was more japonica-like. The SSP and MSP further diverged into five (HN, GD-GX1, GX2, FJ and YN) and two (JX-HuN1 and HuN2) geographical populations, respectively. The genetic data suggest the isolation by distance, although water systems also appear to play an important role in the formation of homogenous populations, and occasionally landscape was also involved. The population GD-GX1, which grew widely in Guangdong and Guangxi provinces, was the largest geographical population in China. It had a high level of genetic diversity (GD) and the closest genetic relationship with other inferred populations. The population HN, with the smallest SSR molecular weights and the highest level of GD, may be the most ancestral population.
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Li J, Zhang HL, Wang Z, Liang YM, Jiang L, Ma W, Yang DP. [Determination content of the antidepressant extraction and analysis the trace elements from Morinda officinalis]. ZHONG YAO CAI = ZHONGYAOCAI = JOURNAL OF CHINESE MEDICINAL MATERIALS 2008; 31:1337-1340. [PMID: 19180952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE To study on the antidepressive extraction and determinated the content of the oligosaccharides I , the proteins and the trace elements from Morinda officinalis. METHODS We analyzed the content of the total oligosaccharides, the proteins and the trace elements by Phenol-Sulferic acid, Coomassie brilliant blue and inductive coupling plasm atomic emission spectrometer (ICP-AES) methods, respectively. RESULTS The percent of the oligosaccharides and the proteins were 89.4% and 0.19% in the extraction from M. officinalis, respectively. The total actively oligosaccharides I were subjected to the D-941 ion column chromatography to give the extraction in which hardly and protein were determined. 12 kinds of trace element including Zn, Fe, Ca ect. in the extraction (the oligosaccharides I) were determined by ICP-AES without the noxious trace elements including As, Cd, Pb ect. CONCLUSION The antidepressive activity extraction(the oligosaccharides I ) was a highly pure and vegetal oligosaccharides.
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Zhang HL, Lin HH, Tao L, Ma XH, Dai JL, Jia J, Cao ZW. Prediction of antibiotic resistance proteins from sequence-derived properties irrespective of sequence similarity. Int J Antimicrob Agents 2008; 32:221-6. [PMID: 18583101 DOI: 10.1016/j.ijantimicag.2008.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 03/13/2008] [Accepted: 03/15/2008] [Indexed: 11/29/2022]
Abstract
Increasing antibiotic resistance has become a worldwide challenge to the clinical treatment of infectious diseases. The identification of antibiotic resistance proteins (ARPs) would be helpful in the discovery of new therapeutic targets and the design of novel drugs to control the potential spread of antibiotic resistance. In this work, a support vector machine (SVM)-based ARP prediction system was developed using 1308 ARPs and 15587 non-ARPs. Its performance was evaluated using 313 ARPs and 7156 non-ARPs. The computed prediction accuracy was 88.5% for ARPs and 99.2% for non-ARPs. A potential application of this method is the identification of ARPs non-homologous to proteins of known function. Further genome screening found that ca. 3.5% and 3.2% of proteins in Escherichia coli and Staphylococcus aureus, respectively, are potential ARPs. These results suggest the usefulness of SVMs for facilitating the identification of ARPs. The software can be accessed at SARPI (Server for Antibiotic Resistance Protein Identification).
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Kushvaha SS, Xu H, Zhang HL, Wee ATS, Wang XS. Shape-controlled growth of indium and aluminum nanostructures on MoS2(0001). JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2008; 8:2707-2712. [PMID: 18572713 DOI: 10.1166/jnn.2008.460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The growth of indium and aluminum nanostructures on molybdenum disulphide (MoS2)(0001) substrate has been studied using scanning tunneling microscopy in ultra-high vacuum. At low coverage and room temperature (RT), mostly ultra-thin (approximately 1.2-2 nm) triangular In islands were observed on MoS2. With increasing coverage or high flux, large coalesced irregular islands along with triangular and round-shaped ones of increased average height were found. Triangular and round-shaped islands were obtained after annealing the RT-deposited In on MoS2 sample at 450 K. At approximately 375 K, exclusively triangular In islands were observed. Al nanoparticles with diameter in 4-16 nm range were obtained after a low-flux deposited whereas ramified islands were observed in a high flux at RT. Ultra-thin (approximately 1.20-2 nm) Al islands and films were obtained on MoS2 after deposition at 500 K. These results demonstrate that the shape of In and Al nanostructures grown on MoS2 can be controlled in self-assembly by adjusting substrate temperature, deposition flux and amount.
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Zhu F, Han LY, Chen X, Lin HH, Ong S, Xie B, Zhang HL, Chen YZ. Homology-free prediction of functional class of proteins and peptides by support vector machines. Curr Protein Pept Sci 2008; 9:70-95. [PMID: 18336324 DOI: 10.2174/138920308783565697] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Protein and peptide sequences contain clues for functional prediction. A challenge is to predict sequences that show low or no homology to proteins or peptides of known function. A machine learning method, support vector machines (SVM), has recently been explored for predicting functional class of proteins and peptides from sequence-derived properties irrespective of sequence similarity, which has shown impressive performance for predicting a wide range of protein and peptide classes including certain low- and non- homologous sequences. This method serves as a new and valuable addition to complement the extensively-used alignment-based, clustering-based, and structure-based functional prediction methods. This article evaluates the strategies, current progresses, reported prediction performances, available software tools, and underlying difficulties in using SVM for predicting the functional class of proteins and peptides.
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