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Zhang AP, Liu CF, Sun RC, Xie J, Chen XY. Homogeneous acylation of eucalyptus wood at room temperature in dimethyl sulfoxide/N-methylimidazole. BIORESOURCE TECHNOLOGY 2012; 125:328-331. [PMID: 23069606 DOI: 10.1016/j.biortech.2012.08.131] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 07/24/2012] [Accepted: 08/28/2012] [Indexed: 06/01/2023]
Abstract
Succinoylation and benzoylation of ball-milled eucalyptus wood using succinic anhydride and benzoyl chloride as acylating reagent, respectively, were investigated at room temperature using dimethyl sulfoxide/N-methylimidazole (DMSO/NMI) as reaction medium without additional catalysts. The effects of the corresponding acylating reagent dosage (1-5:1 for succinoylation and 0.5-5:1 for benzoylation) and reaction time (0.35-5h for succinoylation and 0.5-3h for benzoylation) on the extent of acylation, measured by weight percent gain (WPG), were studied. WPG of succinoylation and benzoylation was in the range of 70.8-144.7% and 17.3-43.1%, respectively. The efficiency of acylation at room temperature significantly increased in DMSO/NMI compared with ionic liquid 1-butyl-3-methylimidazolium chloride because of the role of NMI as solvent, base and catalyst. Fourier transform infrared (FT-IR), and solid-state cross-polarization/magic-angle spinning (CP/MAS) (13)C nuclear magnetic resonance (NMR) spectroscopy studies provided evidence for the occurrence of succinoylation and benzoylation reactions and the attachment of functional groups via ester bonds.
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Xiong L, Leung HW, Chen XY, Han JH, Leung WH, Soo OY, Lau YL, Wong KS. Autonomic dysfunction in ischemic stroke with carotid stenosis. Acta Neurol Scand 2012; 126:122-8. [PMID: 22077726 DOI: 10.1111/j.1600-0404.2011.01617.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVES Impaired autonomic function is common in acute ischemic stroke. Previous limited studies have suggested that atherosclerosis may affect the distensibility of the carotid sinus and then impair the cardiovascular autonomic function. This study sought to investigate cardiovascular autonomic function in patients with ischemic stroke with carotid stenosis. METHODS Eighty-five patients with ischemic stroke (58 ones without carotid stenosis and 27 ones with carotid stenosis, average 6 months after stroke onset) and 37 elderly controls were recruited. All performed Ewing's battery autonomic function tests. RESULTS From Ewing's battery of autonomic function tests, atypical, definite, or severe autonomic dysfunction was identified in 69.0% patients without carotid stenosis and 88.9% with carotid stenosis, with significant difference between the two groups, and the prevalence of autonomic dysfunction in both groups was higher than that in controls (21.6%). Patients with carotid stenosis showed impairment of all parasympathetic tests (all P < 0.05) and one of the sympathetic tests [Mean fall in systolic blood pressure (BP) on standing: P = 0.051], and those without carotid stenosis only showed impairment in two parasympathetic tests (Valsalva ratio: P = 0.014; heart rate response to deep breathing: P < 0.001) in comparison with controls. Patients with carotid stenosis had significantly more impairment than those without carotid stenosis in some autonomic parameters (Valsalva ratio: P < 0.05; mean fall in systolic BP on standing: P < 0.05). CONCLUSIONS Cardiovascular autonomic function is impaired in patients with ischemic stroke, but patients with carotid stenosis show more severely impaired parasympathetic and sympathetic functions.
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Djurisic AB, Chen XY, Leung YH. Recent progress in hydrothermal synthesis of zinc oxide nanomaterials. RECENT PATENTS ON NANOTECHNOLOGY 2012; 6:124-134. [PMID: 22292608 DOI: 10.2174/187221012800270180] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 09/29/2011] [Accepted: 12/11/2011] [Indexed: 05/31/2023]
Abstract
Hydrothermal synthesis is of considerable interest due to its low cost, simplicity and relatively low growth temperature (typically below 200 °C). Since the synthesis is performed in aqueous solutions (no organic solvents), it can also be safe and environmentally friendly (depending on precursor chemicals). Consequently, it has been a subject of intense research in recent years. In this article, we review recent progress in hydrothermal synthesis of zinc oxide nanomaterials, with focus on practical relevance for a variety of applications.
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Zheng LP, Yang JX, Chen XY. A new species of Triplophysa (Nemacheilidae: Cypriniformes), from Guangxi, southern China. JOURNAL OF FISH BIOLOGY 2012; 80:831-841. [PMID: 22471802 DOI: 10.1111/j.1095-8649.2012.03227.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A new species, Triplophysa huapingensis, is described from the Hongshuihe River, Guangxi, China. The new species is distinguished from other species of Triplophysa by the following combination of characters: body covered with scales, lateral line complete, eyes not degenerate, dorsal fin truncate, caudal fin forked, tip of pelvic fin not reaching anus, eight branched rays of dorsal fin, six branched rays of pelvic fin, 16 branched rays of caudal fin, grey and black diffused blotches on dorsal and lateral head and body. A key to all recorded species of Triplophysa in the Xijiang River system is provided.
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Liaw YF, Jia JD, Chan HLY, Han KH, Tanwandee T, Chuang WL, Tan DM, Chen XY, Gane E, Piratvisuth T, Chen L, Xie Q, Sung JJY, Wat C, Bernaards C, Cui Y, Marcellin P. Shorter durations and lower doses of peginterferon alfa-2a are associated with inferior hepatitis B e antigen seroconversion rates in hepatitis B virus genotypes B or C. Hepatology 2011; 54:1591-9. [PMID: 22045673 DOI: 10.1002/hep.24555] [Citation(s) in RCA: 165] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
UNLABELLED As there is currently a lack of consensus on the most appropriate dose and duration of peginterferon alfa-2a (PEG-IFNα-2a) therapy in hepatitis B e antigen (HBeAg)-positive patients, the efficacy and safety of either 24 or 48 weeks' duration and 90 μg/week or 180 μg/week doses were compared. HBeAg-positive patients (n = 544; 34% genotype B, 51% genotype C) were randomized to receive PEG-IFNα-2a (2 × 2 factorial design) for 24 or 48 weeks and at 90 μg/week or 180 μg/week and included in the per-protocol population. The primary efficacy endpoint of the noninferiority study was HBeAg seroconversion 6 months posttreatment. The prespecified odds ratio (OR) noninferiority margin was 1.88 with a one-sided significance level of 0.025. The highest rates of HBeAg seroconversion 6 months posttreatment were in the 180/48 arm (36.2% versus 14.1%-25.8% in the other arms). When the dose and duration arms were pooled, the OR for noninferiority of 24 weeks versus 48 weeks was 2.17 (95% confidence interval [CI] 1.43, 3.31; P = 0.749) and for 90 μg versus 180 μg was 1.79 (95% CI 1.18, 2.72; P = 0.410). As the upper limit of the 95% CI of the ORs were >1.88, 24 weeks were inferior to 48 weeks and 90 μg/week was inferior to 180 μg/week. The highest rates of response in the 180/48 arm were achieved by patients with HBsAg <1,500 IU/mL at Week 12 (58%) or Week 24 (57%), whereas patients with HBsAg >20,000 IU/mL did not respond. Adverse events were typical of those associated with PEG-IFNα-2a. CONCLUSION Compared with lower doses and shorter durations, the licensed PEG-IFNα-2a treatment regimen (180 μg/48 weeks) was the most efficacious and beneficial for HBeAg-positive patients predominantly infected with hepatitis B virus genotypes B or C.
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Xue HB, Tan HH, Liu WZ, Chen XY, Feng N, Gao YJ, Song Y, Zhao YJ, Ge ZZ. A pilot study of endoscopic spray cryotherapy by pressurized carbon dioxide gas for Barrett's esophagus. Endoscopy 2011; 43:379-85. [PMID: 21437849 DOI: 10.1055/s-0030-1256334] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND STUDY AIMS Endoscopic spray cryoablation is a novel approach for the treatment of Barrett's esophagus. However, few studies have reported its efficacy, especially with the use of carbon dioxide (CO (2)). The aim of the current study was to evaluate the short term efficacy and complications using CO (2) in endoscopic cryoablation of Barrett's esophagus. METHODS Patients diagnosed with Barrett's esophagus underwent monthly stepwise cryoablation with pressurized CO (2) gas, with follow-up esophageal biopsies until complete histological reversal was achieved. Responses were analyzed with an intention-to-treat analysis according to complete response for intestinal metaplasia (CR-IM), which was defined as the elimination of all intestinal metaplasia including specialized intestinal metaplasia (SIM), subsquamous SIM, and dysplasia with intestinal metaplasia in the biopsies under narrow-band imaging (NBI). RESULTS In total, 22 patients were enrolled, 20 of whom completed the treatment. Two patients declined further ablation after the first cryotherapy session. A total of 44 sessions were performed; a median of 2 sessions per patient (range 1 - 3 sessions) were needed to complete the ablation of Barrett's esophagus. No severe complications occurred. Follow-up endoscopies were performed in 20 patients (90.9 %). Two patients (9.1 %) were lost to follow-up. Median follow-up was 10 months (range 6 - 18 months). After cryotherapy, 20 patients (90.9 %) reached CR-IM of Barrett's esophagus. Patients underwent a median number of 3 follow-up endoscopies (range 2 - 4) with biopsies. At 6 months, recurrence was evident in three patients (13.6 % of the overall population, 15.0 % of the CR-IM population). One of the three patients developed intestinal metaplasia but no dysplastic change and the other two developed subsquamous SIM. CONCLUSIONS The pressurized CO (2) spray cryotherapy is a relatively effective and safe endoscopic treatment for Barrett's esophagus.
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Chen S, Ma GP, Wang MS, Cheng AC, Zhu DK, Luo QH, Jia RY, Liu F, Chen XY, Han XF, Bo Y, Zhou DC. Efficacy study and field application of an inactivated new type gosling viral enteritis virus vaccine for domestic geese. Poult Sci 2011; 90:766-74. [PMID: 21406361 DOI: 10.3382/ps.2010-01135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
New type gosling viral enteritis virus (NGVEV) caused a serious disease in naive juvenile goslings. In the described studies the performance of 2 vaccines was analyzed: a vaccine containing adjuvanted inactivated NGVEV and a vaccine containing adjuvanted inactivated NGVEV and recombinant goose IL-2. Breeder geese were subcutaneously vaccinated at the beginning of the egg production period with the vaccines. Breeder geese sham vaccinated with PBS served as control. The cellular and humoral immune responses of the vaccinated breeder geese, as well as the presence of maternally derived antibody to NGVEV, were investigated by ELISA, virus neutralization test, and lymphocyte proliferation assay, respectively. A significantly higher immunogenicity (P < 0.05) was induced by the inactivated NGVEV-recombinant goose IL-2 adjuvant vaccine compared with the inactivated NGVEV vaccine. The offspring of the vaccinated birds were challenged with virulent NGVEV (100 50% lethal dose) and the protective efficacy of the vaccines was determined. Furthermore, in a field trial the efficacy of the inactivated NGVEV vaccine was recorded from years 2003 to 2007. No clinical signs or abnormal health status were observed in the vaccinated breeder geese and the progeny. After a single application, >80% protection was shown in the progeny of geese vaccinated against NGVEV challenge for approximately 5 mo. The extensive field trials further demonstrated that vaccination of breeder geese with the inactivated NGVEV vaccine could be a safe and efficacious means to control NGVE disease. Moreover, the level of maternally derived NGVEV antibody titer in the egg yolk reflected the level of NGVEV antibodies in the breeder geese, suggesting that the egg yolk could be used to monitor the vaccination efficacy in commercial goose breeder flocks.
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Chen XY, Sui C, Gan BC, Wei JH, Zhou YK. First Report of Corynespora Leaf Spot on Patchouli Caused by Corynespora cassiicola in China. PLANT DISEASE 2010; 94:1508. [PMID: 30743376 DOI: 10.1094/pdis-07-10-0492] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Patchouli (Pogostemon cablin (Blanco) Benth.) is mainly cultivated in Southeast Asia as a medicinal shrub and a source of patchouli oil used in perfumery. In 2008, a leaf spot disease was observed on patchouli plants grown on most farms (some farms had 99% incidence) in Wanning, the predominant cultivation location in the Hainan Province of China. The disease usually began at the tip of leaves, the main veins, or small veinlets. Severely irregular-shaped dark brown leaf spots expanded over 5 to 10 days, eventually causing infected leaves to abscise. The time from initial leaf lesions to abscission usually took 1 month. The disease was usually most severe in April and May, causing significant economic losses along with quality losses to patchouli oil extracted from leaves. To isolate the causal pathogen, diseased leaves were collected in August 2008 from a farm of the Hainan Branch Institute of Medicinal Plant Development in Wanning, surface sterilized in 75% ethanol for 1 min, transferred to potato dextrose agar (PDA), and incubated at 28°C for 14 days. Single-spore cultures of three isolates were obtained and identified as Corynespora cassiicola (Berk. & Curt.) Wei. on the basis of morphological and physiological features (1). Genomic DNA was extracted from all the cultures. The internal transcribed spacer (ITS) region of the rDNA was amplified using primers ITS1 (5'-TCCGATGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3'). Amplicons were 546 bp (GenBank Accession No. HM145960) and had 99% nucleotide identity with the corresponding sequence (GenBank Accession No. GU138988) of C. cassiicola isolated from cassava (Manihot esculenta Crantz). To satisfy Koch's postulates, 50-day-old potted plants in a tent were sprayed until runoff with a spore suspension (1 × 106 spores/ml) prepared from 10-day-old cultures. Using this spray method, one isolate was inoculated separately onto nine leaves of three potted plants. The potted plants were covered with plastic bags to maintain high humidity for 48 h and then placed outside under natural environmental conditions (temperature 20 to 28°C). Another nine leaves of three potted plants, sprayed only with sterile water, served as noninoculated control plants. Leaf spot symptoms similar to those on diseased field plants appeared after 7 days on all inoculated plants. C. cassiicola was reisolated from all inoculated test plants. No symptoms were observed on the control plants. To our knowledge, this is the first report of C. cassiicola causing a leaf spot disease on patchouli in China. Other previous reports of this disease were from Cuba (2). This pathogen has also been reported previously to be economically important on a number of other hosts. On patchouli plants, more attention should be given to prevention and control measures to help manage this disease. References: (1) M. B. Ellis. Dematiaceous Hyphomycetes. Commonwealth Mycological Institute: Kew, Surrey, England, 1971. (2) I. Sandoval et al. Cienc. Tec. Agric., Prot. Plant. 10:21, 1987.
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Shen FX, Ma GP, Cheng AC, Wang MS, Li CF, Sun KF, Chang H, Zhu DK, Jia RY, Chen XY, Sun T. Development and application of an indirect immunohistochemical method for the detection of duck plague virus vaccine antigens in paraffin sections and localization in the vaccinated duckling tissues. Poult Sci 2010; 89:1915-23. [PMID: 20709976 DOI: 10.3382/ps.2010-00848] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The objective of the present study was to develop and apply a streptavidin-alkaline phosphatase labeling system of indirect immunohistochemistry (SP-IHC) to detect antigenic distribution and localization regularity of duck plague virus (DPV) vaccine antigens in paraformaldehyde-fixed paraffin-embedded tissues of experimentally vaccinated ducklings. Male New Zealand rabbits were immunized with purified DPV antigens, which were engaged by a combination of differential centrifugation and sucrose-density gradient ultracentrifugation. The rabbit anti-DPV polyclonal antibodies were purified and used as the primary antibodies. Forty-eight 28-d-old DPV-free Pekin ducklings were subcutaneously inoculated with attenuated DPV vaccine in the immunization group and sterile PBS in the control group. The tissues were collected at sequential time points between 4 h and 18 wk postvaccination (PV) and were prepared for SP-IHC observation. The presence of DPV-specific antigens was first observed in the liver and spleen at 12 h PV; in the bursa of Fabricius, thymus, Harderian gland, esophagus, and intestinal tract at 1 d PV; and in the heart, lung, kidney, pancreas, and brain at 3 d PV. The positive staining reaction could be detected in the vaccinated duckling tissues until 18 wk PV, and no positive staining cells could be observed in the controls. The highest levels of positive staining reaction were found in the liver, spleen, bursa of Fabricius, thymus, and intestinal tract, whereas a few DPV vaccine antigens were distributed in the heart, pancreas, and esophagus. The target cells had a ubiquitous distribution, especially in the mucosal epithelial cells, lamina propria cells, macrophages, hepatocytes, and lymphocytes, which served as the principal sites for antigen localization. These findings demonstrated that SP-IHC was a reliable method for detecting antigenic distribution and localization regularity of DPV vaccine antigens in routine paraffin sections. The present study may be useful for describing proliferation and distribution regularity of DPV vaccine in the vaccinated duckling tissues and enhance further studies and clinical application of attenuated DPV vaccine.
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Chen S, Cheng AC, Wang MS, Zhu DK, Jia RY, Luo QH, Liu F, Chen XY, Yang JL. Humoral and cellular immune responses in adult geese induced by an inactivated vaccine against new type gosling viral enteritis virus. Poult Sci 2010; 89:2410-8. [PMID: 20952704 DOI: 10.3382/ps.2010-00958] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To assess the immunogenicity of an inactivated new type gosling viral enteritis virus (NGVEV) vaccine, we investigated 3 different doses of the inactivated vaccine and the inactivated vaccine in conjunction with 3 different doses of recombinant goose interleukin-2 (rGoIL-2) adjuvant. A virus concentration of 10(5) 50% embryo infective dose/mL was subcutaneously inoculated into adult geese divided into 6 groups. The dynamic changes of the humoral and cellular immunity responses elicited by the vaccines in the adult geese postvaccination (PV) were investigated using ELISA, virus neutralization test, and lymphocyte proliferation assay. The clearance of virus from the intestines of geese (175 d PV) was studied by histopathological examination and indirect immunofluorescence assay after virulent NGVEV challenge. This study showed that the inactivated NGVEV vaccine elicits strong humoral and cellular responses in the vaccinated adult geese. The absorbance values of specific anti-NGVEV antibodies, the neutralization antibody titer, and the lymphocyte proliferation index rapidly increased, peaked at about 28 d PV, progressed to the plateau stage, and then decreased slightly. The rGoIL-2 adjuvant enhanced the immune response, and this adjuvant in conjunction with the inactivated NGVEV vaccine induces a significantly higher specific anti-NGVEV antibody absorbance value, neutralization antibody titer, and lymphocyte proliferation index than the non-adjuvant-inactivated NGVEV vaccine (P < 0.05). The inactivated NGVEV vaccine conferred adequate efficient ability to clear NGVEV in vaccinated geese even in the last phase of the vaccination period (175 d PV). The inactivated NGVEV vaccine (0.5 mL/goose) with 1,000 units of rGoIL-2 adjuvant/goose is the most effective dose, thereby eliciting the strongest humoral and cellular immunity responses and providing the most efficacious clearance of NGVEV in vivo.
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Mok VCT, Lam WWM, Chen XY, Wong A, Ng PW, Tsoi TH, Yeung V, Liu R, Soo Y, Leung TW, Wong KS. Statins for asymptomatic middle cerebral artery stenosis: The Regression of Cerebral Artery Stenosis study. Cerebrovasc Dis 2009; 28:18-25. [PMID: 19420918 DOI: 10.1159/000215939] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2008] [Accepted: 01/21/2009] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The progression of cerebral atherosclerosis increases the risk of stroke and vascular events. Given the known benefits of statins in retarding coronary and carotid atherosclerosis progression, we studied the effects of statins on asymptomatic middle cerebral artery (MCA) stenosis progression. METHODS We conducted a randomized, double-blind, placebo-controlled study to evaluate the effects of simvastatin on the progression of MCA stenosis among stroke-free individuals who had mild to moderately elevated LDL cholesterol (3.0-5.0 mmol/l). Two hundred and twenty-seven subjects were randomized to either placebo (n = 114) or simvastatin 20 mg daily (n = 113). The severity of MCA stenosis at baseline and at the end of the study was graded by MRA into normal, minimal (<10%), mild (10-49%), moderate (50-90%) and severe (>90%). The primary outcome was the change in grading of MCA stenosis over 2 years. RESULTS At the end of the study, the LDL cholesterol level decreased by 1.43 and 0.12 mmol/l for the active and placebo groups, respectively (p < 0.001). There was no significant difference in the proportion of patients having stable, progressive and regressive MCA stenosis between the placebo (72, 22 and 6%) and active groups (78.6, 15.5 and 5.8%). The all-cause mortality was significantly lower in the active group (n = 0) relative to the placebo group (n = 7, p = 0.014). Any clinical events were also lower in the active group (n = 5) than in the placebo group (n = 13, p = 0.052). CONCLUSIONS Simvastatin 20 mg daily had no apparent effect upon the evolution of asymptomatic MCA stenosis over 2 years.
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Cheng J, Ju XL, Chen XY, Liu GY. Homology modeling of human α1β2γ2 and house fly β3 GABA receptor channels and Surflex-docking of fipronil. J Mol Model 2009; 15:1145-53. [DOI: 10.1007/s00894-009-0477-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2008] [Accepted: 01/22/2009] [Indexed: 11/29/2022]
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Liu P, Cao YL, Wang CX, Chen XY, Yang GW. Micro- and nanocubes of carbon with C8-like and blue luminescence. NANO LETTERS 2008; 8:2570-2575. [PMID: 18651780 DOI: 10.1021/nl801392v] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Micro- and nanocubes of carbon have been synthesized by laser ablation in liquid. The morphology and structure analyses indicated that these micro- and nanocubes are single crystals with a body-centered cubic structure with a lattice constant of 5.46 angstroms, which is so-called C 8-like structure, and they have a slightly truncated shape bounded mainly by (200) facets. A blue-purple luminescence at room temperature was observed in the cathodoluminescence spectrum of the synthesized single micro- and nanocube of carbon, which exhibited that this unique carbon nanomaterial is a new semiconductor with blue luminescence. The physical and chemical mechanisms of the synthesis of carbon micro- and nanocubes were pursued upon laser ablation in liquid.
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Abstract
BACKGROUND Chemotherapeutic agents such as topotecan can be used to treat ovarian cancer. The effects of using topotecan as a therapeutic agent have not been previously been systematically reviewed. OBJECTIVES To systematically evaluate the effectiveness and safety of topotecan for the treatment of ovarian cancer. SEARCH STRATEGY We searched the Cochrane Central Register of Controlled Trials (CENTRAL), (Issue 4, 2006); Cochrane Gynaecological Cancer Review Group (CGCRG) Specialised Register (Cochrane Library Issue 4, 2006); MEDLINE (January 1990 to 27 July 2006); EMBASE (January 1990 to 27 July 2006); The European Organization for the Research and Treatment of Cancer (EORTC) database (to 1 August 2006); CBM (Chinese Biomedical Database) (January 1990 to 27 July 2006). SELECTION CRITERIA Randomised controlled trials (RCTs) which randomized patients with ovarian cancer to single or combined use of topotecan versus interventions without topotecan, or different remedies of topotecan. DATA COLLECTION AND ANALYSIS Two review authors independently extracted and analysed data. MAIN RESULTS Six studies including 1323 participants were eligible for this review (Gordon 2004a; Gore 2001a; Gore 2002; Hoskins 1998; Huinink 2004; Placido 2004) All studies, as reported, were identified as being of poor methodological quality. Topotecan had comparable effectiveness to prolong progression-free survival (PFS) compared with pegylated liposomal doxorubicin (PLD), (16.1 weeks versus 17.0 weeks; p = 0.095). Overall survival (OS) time was similar in participants using PLD compared with topotecan (56.7 weeks versus 60 weeks; p = 0.341). Topotecan was more hematologically toxic compared with paclitaxel or PLD, relative risks (RRs) of hematological events: ranged from 1.03 to 14.46 and 1.73 to 27.12 respectively. A 21-day cycle of topotecan was more toxic than a 42-day cycle (RRs of hematological and non-hematological events ranged from 1.03 to 8). Intravenous and oral topotecan had comparable toxicity. Topotecan delayed progression more effectively compared with paclitaxel (23.1 weeks versus 14 weeks, p = 0.0021). Participants were more likely to respond to topotecan on a 21-day cycle as opposed to a 42-day cycle (RR 7.23, 95% CI 0.94 to 55.36). Small tumor diameter, sensitivity to platinum-based chemotherapy was associated with better prognosis. Small sample size, methodological flaws and poor reporting of the included trials made measurement bias of the trials difficult to assess. AUTHORS' CONCLUSIONS Topotecan appears to have a similar level of effectiveness as paclitaxel and PLD, though with different patterns of side effects. Larger, well-designed RCTs are required in order to define an optimal regime.
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Li XB, Ge ZZ, Chen XY, Liu WZ. Duodenal gastric metaplasia and Helicobacter pylori infection in patients with diffuse nodular duodenitis. ACTA ACUST UNITED AC 2008; 40:897-902. [PMID: 17653441 DOI: 10.1590/s0100-879x2006005000117] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Accepted: 04/26/2007] [Indexed: 11/22/2022]
Abstract
Whether the regression of gastric metaplasia in the duodenum can be achieved after eradication of Helicobacter pylori is not clear. The aim of the present study was to investigate the relationship between H. pylori infection and gastric metaplasia in patients with endoscopic diffuse nodular duodenitis. Eighty-six patients with endoscopically confirmed nodular duodenitis and 40 control patients with normal duodenal appearance were investigated. The H. pylori-positive patients with duodenitis received anti-H. pylori triple therapy (20 mg omeprazole plus 250 mg clarithromycin and 400 mg metronidazole, all twice daily) for one week. A control endoscopy was performed 6 months after H. pylori treatment. The H. pylori-negative patients with duodenitis received 20 mg omeprazole once daily for 6 months and a control endoscopy was performed 2 weeks after treatment. The prevalence of H. pylori infection was 58.1%, and the prevalence of gastric metaplasia was 57.0%. Seventy-six patients underwent endoscopy again. No influence on the endoscopic appearance of nodular duodenitis was found after eradication of H. pylori or acid suppression therapy. However, gastric metaplasia significantly decreased and complete regression was achieved in 15/28 patients (53.6%) 6 months after eradication of H. pylori, accompanied by significant improvement of other histological alterations. Only mild chronic inflammation, but not gastric metaplasia, was found in the control group, none with H. pylori infection in the duodenal bulb. Therefore, H. pylori infection is related to the extent of gastric metaplasia in the duodenum, but not to the presence of diffuse nodular duodenitis.
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Yang YH, Chen XY, Feng Y, Yang GW. Physical mechanism of blue-shift of UV luminescence of a single pencil-like ZnO nanowire. NANO LETTERS 2007; 7:3879-3883. [PMID: 18001107 DOI: 10.1021/nl071849h] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Cathodoluminescence spectroscopy is used to address the ultraviolet (UV) luminescence of a single pencil-like ZnO nanowire whose diameter gradually reduces from bottom to top in the range of 700-50 nm. It is found that the UV emission energy evidently shifts to the high energy with the ZnO nanowire's diameter decreasing and the blue-shift of 90 meV is observed when the nanowire diameter reduces to 50 from 700 nm. The physical mechanism of the UV blue-shift of the ZnO nanowire is attributed to the Burstein-Moss effect under the high carrier concentration.
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Chen XY, Wu TX, Liu GJ, Wang Q, Zheng J, Wei J, Ni J, Zhou LK, Duan X, Qiao JQ. Chinese medicinal herbs for influenza. Cochrane Database Syst Rev 2007:CD004559. [PMID: 17943819 DOI: 10.1002/14651858.cd004559.pub3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Influenza is an acute respiratory communicable disease which, during epidemics, can cause high morbidity and mortality. Traditional Chinese medicinal herbs, often administered following a particular theory, may be a potential medicine of choice. OBJECTIVES To assess the effect of Chinese medicinal herbs in preventing and treating influenza, and to estimate the frequency of adverse effects. SEARCH STRATEGY We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2007), which includes the Cochrane Acute Respiratory Infections Review Group specialised register; MEDLINE (January 1966 to January 2007); EMBASE (January 1988 to January 2007); CBM (Chinese Biomedical Database) (January 1980 to January 2007); and the Chinese Cochrane Center's Controlled Trials Register (up to January 2007). We also searched Current Controlled Trials (www.controlled-trials.com) and the National Research Register (http://www.update-software.com/National/) for ongoing trials and reference lists of articles. For more information we telephoned and wrote to researchers in the field, as well as trial authors of studies evaluated in the review SELECTION CRITERIA Randomised controlled trials (RCTs) comparing traditional Chinese medicinal herbs with placebo, no treatment, or chemical drugs normally used in preventing and treating uncomplicated influenza patients. DATA COLLECTION AND ANALYSIS Two review authors independently extracted data and assessed trial quality. MAIN RESULTS Two studies involving 1012 participants were reviewed. The methodological quality of both studies was 'poor'. Included RCTs separately compared two medicinal herbs with two different antiviral drugs, precluding any pooling of results. 'Ganmao' capsules were found to be more effective than amantadine in decreasing influenza symptoms and speeding recovery in one study, (in which adverse reactions were mentioned in the amantadine group although no data were reported). There were no significant differences between 'E Shu You' and ribavirin in treating influenza, nor in the occurrence of adverse reaction. AUTHORS' CONCLUSIONS The present evidence is too weak to support or reject the use of Chinese medicinal herbs for preventing and treating influenza. More RCTs with good methodological quality, larger numbers of participants and clear reporting are needed in the future. We recommend that all the clinical trials registered in the Chinese Clinical Trial Register and Chinese journals join in the Joint Statement of Establishing Chinese Clinical Trial Registration and Publishing System.
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Chen XY, Li J, Qi WQ, Shen SH. Experimental change on dopaminergic neurons in striatum of Parkinson disease rats. Histol Histopathol 2007; 22:1085-90. [PMID: 17616935 DOI: 10.14670/hh-22.1085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Parkinson's disease (PD) is a common neurodegenerative disorder characterized by selective and progressive demise of dopamine-containing neurons in the midbrain. In this study, we observe the expression of c-Jun in the striatum of rats with 6-hydroxydopamine (6-OHDA)-lesions after apomorphine (APO) intraperitoneal injection (ip) in substantia nigra compacta (SNc), and to study the mechanism of the rotations behavior. DESIGN The 6-OHDA was unilaterally injected into rat right SNC. The APO- induced abnormal rotations were investigated on the 1st, 4th, 7th, 14th, 21st days after lesion, respectively. Meanwhile dopaminergic degeneration and c-Jun expression were observed with microscope. Nissl's body staining and immunohistochemical method (ABC) were employed to study the changes of tyrosine hydroxylase (TH) and c-Jun in DA neurons. RESULTS We found that the number of dopaminergic neurons decreased gradually in the lesioned site and those neurons' electron-microscopic structure was severe damaged. There were over 75% of dopaminergic neurons lost, contralateral rotations over 7 turns per minute and c-Jun expressing in the ipsilateral striatum. CONCLUSION Dopaminergic neurons deletion may be linked to upregulation of c-Jun.
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Liu SX, Chen XY, Chen X. A TiO2/AC composite photocatalyst with high activity and easy separation prepared by a hydrothermal method. JOURNAL OF HAZARDOUS MATERIALS 2007; 143:257-63. [PMID: 17049160 DOI: 10.1016/j.jhazmat.2006.09.026] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Revised: 09/01/2006] [Accepted: 09/07/2006] [Indexed: 05/12/2023]
Abstract
In the present work, a TiO2/activated carbon (AC) photocatalyst with high activity and easy separation was prepared using a hydrothermal method. Phenol, methyl orange (MO) and Cr(VI) were used as target pollutants to test the activity and decantability. SEM, XRD, FTIR, diffuse reflectance spectra (UV/DRS) and N2 adsorption isotherms were used to characterize the crystalline and electronic structure. Results show that the AC composite has a significant effect on the TiO2 activity. With suitable AC content, the TiO2/xAC catalysts prepared were much more active. The TiO2/5AC catalyst exhibited easy separation and less deactivation after several runs, and was less sensitive to pH changes. UV/DRS revealed that no electronic bandgap changes in TiO2 occurred on addition of the AC. SEM and XRD results suggest that better TiO2 distribution can be achieved when an optimal AC content is used. A Ti-O-C bond was formed and a slight conjugation effect appeared between the AC bulk and TiO2. The advantages of the obtained TiO2/5AC catalyst revealed its great practical potential in wastewater treatment.
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Liu SX, Chen X, Chen XY, Liu ZF, Wang HL. Activated carbon with excellent chromium(VI) adsorption performance prepared by acid-base surface modification. JOURNAL OF HAZARDOUS MATERIALS 2007; 141:315-9. [PMID: 16914264 DOI: 10.1016/j.jhazmat.2006.07.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2005] [Revised: 07/01/2006] [Accepted: 07/04/2006] [Indexed: 05/11/2023]
Abstract
In the present work, activated carbon (AC) with excellent Cr(VI) adsorption performance especially at low concentrations was prepared by an acid-base surface modification method. Raw activated carbon (AC(0)) was first oxidized in boiling HNO(3) (AC(1)), then treated with a mixture of NaOH and NaCl (AC(2)). Batch equilibrium and continuous column adsorption were conducted to evaluate the adsorption performance. Boehm titration, elemental analysis, and N(2)/77K adsorption isotherm methods were used to characterize the surface properties and pore structure of modified ACs. The results revealed that the modified AC exhibited excellent Cr(VI) adsorption performance in terms of adsorption capacity and adsorption rate: AC(2)>AC(1)>AC(0). Modification caused S(BET) to decrease and the total number of surface oxygen acidic groups to increase. HNO(3) oxidization produced positive acid groups, and subsequently NaOH treatment replaced H(+) of surface acid groups by Na(+), and the acidity of AC decreased. The main cause of higher Cr(VI) adsorption capacity and rate for AC(2) was the presence of more oxygen surface acidic groups and suitable surface acidity. HNO(3)-NaOH modification shows potential for the preparation of high quality AC for the effective removal of low concentrations of Cr(VI).
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Chen XY, He L, Kong SY, Li Q, Zhou MK. Sanchi for acute ischaemic stroke. THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS 2007. [DOI: 10.1002/14651858.cd006305] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Chen XY, Yu YY, Ma LN, Huang YL, Shen CL, Zhang WJ, Xu DZ, Si CW. [Effects of antiviral effects of agents and prognosis of chronic hepatitis B.]. ZHONGHUA SHI YAN HE LIN CHUANG BING DU XUE ZA ZHI = ZHONGHUA SHIYAN HE LINCHUANG BINGDUXUE ZAZHI = CHINESE JOURNAL OF EXPERIMENTAL AND CLINICAL VIROLOGY 2006; 20:219-22. [PMID: 17086275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
BACKGROUND To analyze the effects of difference antiviral agents and the effects of the treatments on long-term prognosis. METHODS Retrospective research method was applied. RESULTS About 40% of the patients were treated with interferon or lamivudine. After the treatment, in lamivudine group, the negative rate of HBV DNA was the highest. In the interferon group, the sero conversion rates of HBeAg/HBeAb were 22.9%. In the antiviral treatment patients, the disease progression and the occurrence of cirrhosis and liver cancer were much lower than those of the control groups. The mortality of cirrhosis and liver cancer in the HBeAg/HBeAb sero converted group was much lower than that of the group without HBeAg/HBeAb sero conversion groups (P less than 0.05). CONCLUSION The antiviral effects of interferon and lamivudine were better than those of the other drug groups. The antiviral drugs could relieve the disease progression and reduce the mortality of cirrhosis and liver cancer.
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Mo HB, Chen XY, Liu Y, Xia F, Yang KQ. Development of a multifunctional and efficient conjugal plasmid for use in Streptomyces spp. Appl Microbiol Biotechnol 2006; 70:705-10. [PMID: 16532313 DOI: 10.1007/s00253-006-0324-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2005] [Revised: 12/31/2005] [Accepted: 01/03/2006] [Indexed: 11/30/2022]
Abstract
A plasmid, pGB112, has recently been developed to transfer DNA from Escherichia coli to Streptomyces spp via conjugation. This technique made use of (A) E. coli replicon, (B) ampicillin (amp) resistance gene for selection in E. coli and thiostrepton (tsr) resistance gene for selection in Streptomyces, (C) a fragment of SCP2* replicon, (D) a 2.6 kb fragment of tra-cassette which consists of pIJ101 transfer gene (tra) and two ermE promoters, (E) a 0.8 kb fragment of oriT of (IncP) RK2. The results showed that this plasmid was able to transfer plasmid DNA from E. coli to Streptomyces coelicolor via conjugation, and that it could also transfer DNA between Streptomyces strains. Since this plasmid has both pBR322 and SCP2* replicons, it may provide a novel and useful method for genetic operation in E. coli and Streptomyces.
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Shi XG, Fawcett JP, Chen XY, Zhong DF. Structural identification of bitespiramycin metabolites in rat: a single oral dose study. Xenobiotica 2005; 35:343-58. [PMID: 16019956 DOI: 10.1080/00498250500087580] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Bitespiramycin is a macrolide antibiotic consisting of a mixture of some nine spiramycin ester derivatives. It has a similar spectrum of antibiotic activity to that of spiramycin but has superior pharmacokinetic properties. In this study, a rapid and facile LC/ESI-MSn method was applied to study the metabolism of bitespiramycin in rat following a single oral dose (80 mg kg-1). Concentrations of parent drug constituents and metabolites were determined in plasma, urine, feces and bile. Concentrations of parent drug constituents and metabolites in plasma were very low. In urine, feces and bile, parent drug constituents and 38 metabolites were identified on the basis of their chromatographic and mass spectrometric properties. The identity of 17 metabolites was confirmed by comparison with reference substances. The principal metabolites were the corresponding spiramycins formed by hydrolysis of the 4''-(3-methylbutanoate) groups. Other important metabolic pathways were: hydrolytic loss of the forosamine and mycarose sugars; aldehyde reduction; cysteine conjugation of the aldehyde group; and hydrolysis of the lactone ring. Products formed by lactone ring opening were found only in urine, and those formed by aldehyde reduction were found only in feces. Aldehyde reduction and hydrolytic loss of forosamine represent novel biotransformation pathways for spiramycin derivatives.
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Ding GH, Chen JW, Qiao XL, Huang LP, Lin J, Chen XY. Comparison of subcooled liquid vapor pressures of polychlorinated dibenzo-p-dioxins and dibenzofurans predicted by QSPR and GC-RI methods. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2005; 16:301-12. [PMID: 16234172 DOI: 10.1080/10659360500204525] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Subcooled liquid vapor pressures (P(L)) are of great importance for assessing the persistent behavior of organic pollutants. As P(L) cannot be determined by direct experiments, it is of interest to develop and evaluate various predictive methods. In the current study, gas chromatography retention index (GC-RI) and quantitative structure-property relationship (QSPR) methods were used to develop predictive models for P(L) of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The model development was based on P(L) values converted from consistent experimental solid vapor pressures (P(S)). The P(L) values predicted by the two methods are highly consistent with each other, and in-between sets of values predicted by others. Since the QSPR method can be regarded as independent of experiments, and can be used to interpret intermolecular interactions that govern the magnitude of P(L), it may be superior to the GC-RI method.
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