Publications by authors named "Yan Zhong Li"

18 Publications

  • Page 1 of 1

First Report of Leaf Spot Caused by Ramularia sphaeroidea on Vicia villosa var. glabrescens in China.

Plant Dis 2021 Jun 15. Epub 2021 Jun 15.

Lanzhou University, College of Pastoral Agriculture Science and Technology, No. 768, Jiayuguan West Road, Lanzhou, Gansu, China, 730020.

Hairy vetch is widely grown in southwestern China for green manure and forage. In December 2019, a leaf disease occurred on 80% plants of in an eight-hectare field in Qujing(N 25°28'12″, E 103°36'22″), Yunnan Province, China. The disease leaves had irregular, brown to dark brown leaf spots with white mold. Twenty diseased leaves from five plants were randomly collected from the field. The leaf samples were sterilized with 75% ethanol for 30 s and 1% NaClO for 75 s, rinsed three times with sterile distilled water, surface water removed with sterile filter paper, and placed onto potato dextrose agar (PDA) for culture at 20oC. The obtained fungal isolates were purified by transferring 1 to 2 mm hyphal tips onto fresh PDA plates and cultured under the same temperature condition. The isolates grew slowly, at a rate of 0.7 mm/d at 20℃ for 4 weeks. A diseased plant specimen (accession MHLZU19326) and three isolates (accessions YN1931401, YN1931402, and YN1931403) were deposited in the Mycological Herbarium of Lanzhou University (MHLZU). Conidia from the PDA cultures were hyaline, spherical, smooth, aseptate, and measured 2.13 to 3.67 × 4.56 to 5.77 μm (n = 50). Conidiophores were hyaline, smooth, and straight. DNA of purified isolates was extracted and the nuclear ribosomal internal transcribed spacer (ITS), , and genes were amplified and sequenced with primers ITS1/ITS4 (White et al. 1990), EF1-728F/EF2 (Carbone and Kohn 1999;O'Donnell et al. 1998), CylH3F/CylH3R (Crous et al. 2004), and gpd1/gpd2 (Berbee et al. 1999), respectively. DNA sequences of isolates YN1931401, YN1931402, and YN1931403 were deposited in GenBank for the ITS (accessions MW092181, MW332205, and MW332206), (MW448172 to MW448174), (MW448175 to MW448177), and (MW448178 to MW448180). These sequences had the highest similarities with sequences of Sacc. in GenBank, 99%(514∕516, 515∕517, and 514∕517 bp) for ITS, 99% (402∕403, 403∕405, and 405∕405bp) for , 99% (377∕378, 378∕378, and 376∕378bp) for , and 100% (558∕557, 557∕559 and 561∕565 bp) for . A phylogenetic tree generated with the sequences clustered the fungus closely with . Infection experiments were carried out with 50 plants of in 10 pots. A conidial suspension of 1. 0 × 106 conidia/ml with 0.01% Tween 80 was prepared by adding sterile distilled water to the YN1931401 culture and scraping with a sterile scalpel. The leaves of 25 healthy plants were sprayed with the conidial suspension, and those of the 25 control plants were sprayed with sterile water. All plants were covered with clear polyethylene bags for 3 days to maintain high humidity and then grown in a greenhouse at diurnal cycles of 18℃ for 18h with light and 22℃ for 6 h in dark. Ten days post-inoculation, the inoculated plants exhibited brown lesions similar to the symptoms observed in the field (Fig. 1-F), whereas no symptoms appeared on the control plants. The same fungus was re-isolated and identified as described above. has been reported on and in Ethiopia and Israel (Braun 1998), on various species including in California, the United States (Koike et al. 2004) and on in China (Zhang et al. 2006), but to our knowledge, this is the first report of this fungus causing leaf spot on in China.
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http://dx.doi.org/10.1094/PDIS-04-21-0862-PDNDOI Listing
June 2021

First report of alfalfa leaf spot caused by Leptosphaerulina australis in China.

Plant Dis 2021 Feb 8. Epub 2021 Feb 8.

Lanzhou University, College of Pastoral Agriculture Science and Technology, No. 768, Jiayuguan West Road, Lanzhou, Gansu, China, 730020.

A disease was observed on alfalfa cultivar WL168 characterized by white to brown leaf spots of regular to round shapes, in Aluhorqin County, Inner Mongolia, China (120°13'23″ to 120°29'14″ E, 43°27'52″to 43°35'16″ N, 281.71m to360.13 m Altitude) during 2019 to 2020. The disease mainly presented in spring one month after re-greening and the incidence was 78.30% in this field. Twenty alfalfa plants with severe symptoms were used for pathogen isolation. The infected tissue was cut into 2 × 2 mm pieces, surface-sterilized (in 75% ethanol and 5% commercial bleach (NaClO) for 30 s and 2 min, respectively), rinsed five times with sterilized distilled water, and dried between sterile filter paper (Wang et al. 2019). The diseased tissue from each plant sample were cultured on potato dextrose agar (PDA) and incubated at 25 °C with 12 h light/day for ten days. A fungus was isolated from the diseased leaves at a 100% frequency. Fungal growth on PDA was round with a black surface, radial edge, and a dirty white center. The ascocarps were moved to a clean microscope slide to release asci and ascospores. Ascocarps were spheroidal, subglobose brown, 120 to 160 µm × 160 to 180 µm, which contain several ascus. The size of ascus were 31.0 to 41.6 μm × 75.0 to 87.5 μm and each asci having eight ascospores. Ascospores were ellipsoid to oblong with a gelatinous sheath, brown, 8.8 to 15.0 µm × 29.9 to 43.0 µm with 2 to 3 horizontal septums, and 0 to 2 vertical septums. A phylogenetic tree was constructed after DNA extraction, PCR with primers to amplify the ITS (VG9: 5'- TTACGTCCCTGCCCTTTGTA-3' and ITS4: 5'-TCCTCCGCTTATTGATATGC-3') and LSU (LR7: 5'-TACTACCACCAAGATCT-3' and LROR: 5'- GTACCCGCTGA ACTTAAGC -3') regions. The LSU (SUB8273071) and ITS (SUB8218291) amplicons showed 99% similarity with L. australis (EU754166.1) in the GenBank. To verify the pathogenicity, fungs plugs were inverted on three compound leaves of 20 alfalfa WL168 for two days. Agar plugs (PDA) were inverted on another 20 alfalfa WL168 three compound leaves which were control. All plants were maintained at 22 °C and 44% relative humidity in a growth chamber. Similar disease symptoms were observed on infected leaves ten days after inoculation, while control plants showed no symptoms. The same fungus was re-isolated from the lesions, and further morphological characterization and molecular assays, as described above. L. australis has been reported on various plants, including Prunusarmeniaca, Dolichos, Poa, Lolium, and Vitis in Australia (Graham and Luttrell., 1961), and also from Korean soil in 2018 (Weilan et al., 2018). Additionally, L. briosiana, which is common in the USA, China, and other countries, causes Leptosphaerulina leaf spot (Samacet al., 2015). L. trifolii is newly reported to occur in China (Liu et al., 2019). To the best of our knowledge, this is the first report of L. australis infecting alfalfa in China. Considering the large planting area in Inner Mongolia, this pathogen may losses to alfalfa cultivation. Hence, future studies should explore aspects of effective management of this disease.
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http://dx.doi.org/10.1094/PDIS-10-20-2136-PDNDOI Listing
February 2021

mTOR/NF-κB signaling pathway protects hippocampal neurons from injury induced by intermittent hypoxia in rats.

Int J Neurosci 2020 May 14:1-10. Epub 2020 May 14.

Department of Otorhinolaryngology, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, P.R. China.

To expound the roles of mTOR and NF-kB signaling pathway in intermittent hypoxia (IH)-induced damage of hippocampal neurons. For rat experiments, mTOR inhibitor (Rapamycin, Rapa) and NF-κB signaling inhibitor (ammonium pyrrolidine dithiocarbamate, PDTC) were applied to inhibit mTOR and NF-κB signaling, respectively. For neuron experiments, hippocampal neurons from rat were successfully cultured. Different concentrations of Rapa and PDTC were added to the cultured hippocampal neurons. Rat or primary hippocampal neurons were exposed to normoxic or IH conditions after administration of Rapa and PDTC. The effects of Rapa and PDTC administration on learning and memory ability of rats and hippocampal injury after IH exposure were assayed by Morris water maze and H&E staining. Electron microscope was utilized to examine primary hippocampal neuron ultrastructure changes after IH exposure and Rapa or PDTC administration. The expressions of NF-κB-p65, IκBα, IKKβ, BDNF, TNF-α, IL-1β, PSD-95 and SYN in hippocampal neurons were examined. Compared with normal control rats or neurons, IH-treated group had elevated expression levels of NF-kB, TNF-α and IL-1β and suppressed expression level of BDNF, PSD-95 and SYN. These results were reversed upon pre-treatment with Rapa and PDTC. Furthermore, IκBα and IKKβ expressions were down-regulated in IH group. No notable difference was manifested in PDTC pre-treatment group, while a prominent increase was shown after Rapa pre-administration. The administration of PDTC and Rapa could prevent IH-induced hippocampal neuron impairment, indicating that inhibition of the mTOR and NF-κB pathway may likely act as a therapeutic target for obstructive sleep apnea.
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http://dx.doi.org/10.1080/00207454.2020.1766460DOI Listing
May 2020

Identification, Characterization, Pathogenicity, and Distribution of in Alfalfa Plants in China.

Plant Dis 2019 Jul 29;103(7):1565-1576. Epub 2019 Apr 29.

1 State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agricultural Science and Technology, Lanzhou University, Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Engineering Research Center of Grassland Industry, 730020 Lanzhou, China.

Verticillium wilt caused by results in severe production losses in alfalfa crops and is a Class A quarantined disease in China. During 2015 to 2017, 365 alfalfa fields from 21 locations in six provinces were surveyed, and 45 fields from three closely located sites in Gansu, China were found to have alfalfa plants with symptoms typical of Verticillium wilt, with disease incidence of 12.6 to 53.6%. Isolates were identified to species using morphological characteristics and a maximum likelihood phylogeny of the concatenated partial sequences of actin, elongation factor, glyceraldehyde-3-phosphate dehydrogenase, and tryptophan synthase gene regions of isolates. Isolation incidence was 93.9% from roots, 71.7% from stems, 66.1% from petioles, and 32.2% from leaves of field-infected plants, indicative of systemic disease and sporadic distribution of this pathogen. In greenhouse tests, the pathogen infected seedlings and colonized vascular tissues when inoculated on seeds, on root tips, in soil, or in injured, but not uninjured, aerial tissues, causing systemic symptoms like those in the field and significant losses. Pathogenicity testing also revealed that five locally grown perennial legumes (stylo, milkvetch, sainfoin, white clover, and red clover) could host , with a high virulence to milkvetch, sainfoin, and stylo. This study confirmed that has become established in some regions of Gansu, China and that is a risk to the alfalfa industry in China.
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http://dx.doi.org/10.1094/PDIS-07-18-1272-REDOI Listing
July 2019

Divalent oseltamivir analogues as potent influenza neuraminidase inhibitors.

Carbohydr Res 2019 May 1;477:32-38. Epub 2019 Apr 1.

Research Centre of Modern Analytical Technology, Tianjin University of Science & Technology, No. 29, 13th Avenue, TEDA, Tianjin, 300457, China; China International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal Chemistry, College of Biotechnology, Tianjin University of Science and Technology, No. 29, 13th Avenue, TEDA, Tianjin, 300457, China. Electronic address:

A panel of divalent oseltamivir and guanidino oseltamivir analogues with esterification on the carboxyl acid group as potent inhibitors of influenza virus neuraminidase was prepared via click reaction. The primary structure activity relationship study demonstrated that appropriate distance between two oseltamivir monomers around 30 Å can crosslink two adjacent neuraminidase tetramers on the virion surface and result in highly effective NA inhibitors against three strains of influenza virus and H7N9 virus like particle. This strategy also provides a basis for the multivalent modification on oseltamivir.
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http://dx.doi.org/10.1016/j.carres.2019.03.012DOI Listing
May 2019

MicroRNA-133a suppresses the proliferation, migration, and invasion of laryngeal carcinoma cells by targeting CD47.

Tumour Biol 2016 Oct 11. Epub 2016 Oct 11.

Department of Otorhinolaryngology, Qilu Hospital of Shandong University, No. 107, West Wenhua Road, Lixia District, Ji'nan, 250012, Shandong, People's Republic of China.

The study aims to investigate the possible mechanisms of microRNA-133a (miR-133a) targeting CD47 on cell proliferation, apoptosis, migration, and invasion in laryngeal carcinoma. Forty-two laryngeal carcinoma tissue specimens confirmed by pathological examination from laryngeal carcinoma patients as the case group were collected, and 20 chronic laryngitis tissues were gathered as the control group. The human laryngeal carcinoma cell line Hep-2 was marked as the miR-133a mimic, negative control (NC), miR-133a inhibitor, CD47-siRNA, miR-133a inhibitor + CD47-siRNA, and Mock groups. The expression of CD47 protein and miR-133a was detected by immunohistochemistry (IHC) and qRT-PCR. Dual luciferase assay system was used to determine the relationship between CD47 and miR-133a. Western blotting was used to measure the protein expression of CD47 and miR-133a. 5-Ethynyl-2'-deoxyuridine (EDU) method was used to detect the cell proliferation, and flow cytometry and Transwell were used to measure the cell apoptosis and migration and invasion, respectively. The miR-133a expression in laryngeal carcinoma tissues was significantly lower, while the CD47 expression was higher than that in chronic laryngitis tissues (both P < 0.01). The expression of miR-133a in the miR-133a mimic group was significantly higher than that in other groups (P < 0.05), and the messenger RNA (mRNA) and protein expression of CD47 in the CD47-siRNA and miR-133a mimic groups were significantly lower than those in the Mock and NC group (all P < 0.05), while the mRNA and protein expression of CD47 in the miR-133a inhibitor group were higher than in other groups (all P < 0.05). After transfection, the CD47-siRNA group had the strongest inhibitory activity, while the number of living cells in the miR-133a inhibitor group was significantly higher than that in other groups (all P < 0.05). The apoptosis rates in the miR-133a mimic and CD47-siRNA groups were significantly higher than that in the Mock and NC groups (all P < 0.05). The cell numbers that penetrated membrane in the miR-133a mimic and CD47-siRNA groups were less than in the Mock and NC groups (all P < 0.05). Upregulated miR-133a could inhibit proliferation, invasion, and migration and promote cell apoptosis in laryngeal carcinoma by targeting CD47. miR-133a targeting CD47 could be a new direction in the diagnosis and treatment of laryngeal carcinoma.
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http://dx.doi.org/10.1007/s13277-016-5451-xDOI Listing
October 2016

Enhanced anti-tumor activity of trichosanthin after combination with a human-derived cell-penetrating peptide, and a possible mechanism of activity.

Fitoterapia 2016 Jul 2;112:183-90. Epub 2016 Apr 2.

Institute of Chinese Materia Medica, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China; Zhejiang Reachall Pharmaceutical Co. Ltd, Zhejiang 322100, China. Electronic address:

Trichosanthin (TCS), a type I ribosome-inactivating protein (RIP-I) and renowned Chinese traditional medicine, displays a broad spectrum of biological and pharmacological properties. Particularly, its anti-tumor activity has received a great deal of attention. However, the cellular mechanism for TCS uptake varies with different tumor cell lines, leading to discrepancies in its reported ability to penetrate cells. In this study, HBD, a human derived cell-penetrating peptide (CPP), was used to improve the delivery of TCS into several types of tumor cells, including HeLa cells. Recombinant TCS (rTCS) with or without the fused HBD peptide was expressed in Escherichia coli cells and successfully purified by Ni-NTA affinity chromatography. The cellular uptake efficiency of FITC-labelled-rTCS-HBD was observed in HeLa cells and compared with the uptake efficiency of non-HBD conjugated rTCS under the same conditions using laser confocal microscopy. Moreover, the IC50 value of rTCS-HBD in the tested tumor cells was much lower than that of rTCS, indicating that HBD could efficiently deliver the rTCS into tumor cells. When compared with rTCS, rTCS-HBD induced higher rates of apoptosis in HeLa cells as analyzed by flow cytometry. Furthermore, the apoptotic events observed in HeLa cells incubated with HBD-fused rTCS included activation of Caspase-9, decrease in the Bcl-2/Bax ratio, and cleavage of PARP. These results strongly suggest the participation of mitochondria in apoptosis. This report illustrates one possible method for achieving the efficient transport of TCS into cells using a CPP as a vector, and increases the likelihood that TCS can be used in the clinic.
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http://dx.doi.org/10.1016/j.fitote.2016.03.019DOI Listing
July 2016

Cardiac structural and functional changes in old elderly patients with obstructive sleep apnoea-hypopnoea syndrome.

J Int Med Res 2014 Apr 20;42(2):395-404. Epub 2014 Jan 20.

Department of Emergency Medicine, Qilu Hospital, Shandong University, Jinan, Shandong Province, China.

Objective: To investigate cardiac structural changes in elderly patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) and the impact on left ventricular systolic and diastolic function.

Methods: The study enrolled elderly patients with OSAHS and age-matched healthy control subjects. Cardiac structure, left ventricular diastolic function and left ventricular systolic function were measured using a Doppler ultrasound scanner and compared between the two groups.

Results: The study included 136 patients with OSAHS and 50 healthy control subjects. There were significant differences in the echocardiography indicators that reflect cardiac structure, including interventricular septum, left ventricle posterior wall thickness, and left ventricular mass and mass index between the two groups. There were significant differences between the two groups in the ventricular septal early diastolic myocardial peak velocity/late diastolic myocardial peak velocity (Em/Am), mitral annulus Em/Am, and left ventricle posterior wall Em/Am. There were also significant differences in the indicators of interventricular septum, mitral annulus and left ventricular posterior wall systolic peak velocity between the two groups.

Conclusion: Elderly patients with OSAHS demonstrated cardiac structural changes and their left ventricular diastolic and systolic functions were significantly diminished.
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http://dx.doi.org/10.1177/0300060513502890DOI Listing
April 2014

A Shortcut to the Optimization of Cellulase Production Using the Mutant Trichoderma reesei YC-108.

Indian J Microbiol 2012 Dec 29;52(4):670-5. Epub 2012 Sep 29.

The Research Centre of Modern Analysis Technology, Tianjin University of Science & Technology, Tianjin, 300457 People's Republic China.

Trichoderma reesei YC-108, a strain isolated by a kind of newly invented plate was found to over produce cellulase and it was then used as a cellulase producer. To get the maximum amount of cellulase, the combination of the medium ingredients, which has a profound influence on metabolic pathway was optimized using response surface methodology. The optimum composition was found to be 24.63 g/L wheat bran, 30.78 g/L avicel, and 19.16 g/L soya-bean cake powder. By using the optimized medium, the filter paper activity (FPA) increased nearly five times to 15.82 IU/mL in a 30 L stirred fermenter, carboxymethyl cellulase activity (CMCase) was increased from 83.02 to 628.05 IU/mL and the CMCase/FPA ratio was nearly doubled compared with the parent strain at initial medium.
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http://dx.doi.org/10.1007/s12088-012-0311-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3516653PMC
December 2012

[Effects of electromagnetic radiation on health and immune function of operators].

Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2013 Aug;31(8):602-5

Hefei Center for Disease Control and Prevention Hefei 230061, China.

Objective: To investigate the effects of electromagnetic radiation on the physiological indices and immune function of operators.

Methods: The general conditions and electromagnetic radiation awareness rate of 205 operators under electromagnetic radiation were evaluated using a self-designed questionnaire. Physical examination, electrocardiography, and routine urine test were performed in these operators. Peripheral blood was collected from the operators under electromagnetic radiation for blood cell counting and biochemical testing, and their peripheral blood lymphocytes were cultured for determination of chromosomal aberrant frequency and micronucleus frequency. The data from these operators (exposure group) were compared with those of 95 ordinary individuals (control group).

Results: The chief complaint of giddiness, tiredness, dizziness, and amnesia showed significant differences between the exposure group and control group (P < 0.01), and the difference in headache became larger with an increase in working years. The awareness rate of electromagnetic radiation damage was significantly higher in the exposure group than in the control group. The difference in bradycardia was significant between the two groups (P <0.01), and the incidence was higher with longer working years. Significant differences between the two groups were also found in the numbers of individuals with elevated alanine aminotransferase, total bilirubin, and direct bilirubin (P < 0.01), populations with increased lymphocyte ratio and decreased neutrophil ratio (P < 0.01), populations with positive occult blood, urobilinogen, and bilirubin tests, and the number of individuals with increased micronucleus frequency of cultured peripheral blood lymphocytes (P < 0.01). In addition, the exposure group had significantly increased complement C3 and C4 (P < 0.01), significantly increased IgG (P < 0.05), and significantly decreased IgM (P < 0.01), as compared with the control group.

Conclusion: Electromagnetic radiation may lead to the changes in physiological indices, genetic effects, and immune function and affect the health and immune function in operators. The adverse effects are increased as the working years increase. So it is important to strengthen occupational protection of operators under electromagnetic radiation.
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August 2013

Nutritional study on Embellisia astragali, a fungal pathogen of milk vetch (Astragalus adsurgens).

Antonie Van Leeuwenhoek 2009 Mar 18;95(3):275-84. Epub 2009 Feb 18.

Key Laboratory of Grassland Agro-ecosystem, Ministry of Agriculture, College of Pastoral Agriculture Science and Technology, Gansu Ecological Research Institute, Lanzhou University, Lanzhou, China.

Embellisia astragali is a strong, virulent pathogen that develops within milk vetch (Astragalus adsurgens). In order to determine nutrient requirements, the fungus was cultured on 9 carbon sources, 9 nitrogen sources, and 13 growth media in the dark at 25 degrees C. Growth rates and sporulation capacity were measured after 4 and 12 weeks. All carbon sources supported growth, but only soluble starch, inulin, and dextrose supported sporulation. In general, better growth was obtained on disaccharides and polysaccharides than on monosaccharides. Compared with no growth on NH(4) (+)-N and urea, the fungus grew little on all NO(3) (-)-N, amino-N, and other organic-N such as peptone. There was no sporulation or very sparse conidia on almost all nitrogen sources with supplied dextrose or soluble starch as sole carbon source. The better growth and sporulation on most of the semidefined media than on defined media indicates that some components in plant or animal material may be vital to the fungus. Sporulation was positively correlated with growth rate in N source experiment at 12 weeks and in growth media experiment at 4 and 12 weeks. The fungus favors grow within agar with growth rate less than 1.18 mm day(-1).
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http://dx.doi.org/10.1007/s10482-009-9310-2DOI Listing
March 2009

Adsorption removal of phosphate from aqueous solution by active red mud.

J Environ Sci (China) 2007 ;19(10):1166-70

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.

Red mud is the waste of alumina industry and has high TiO2 and Fe2O3 content which are active components for the adsorption of anion pollutants. In this study, the uptake of phosphate by red mud activated by heat treatment and acid-heat treatment was investigated. The factors influencing the adsorption were also investigated. The result showed that the red mud sample treated using acid-heat method at 80 degrees C with 0.25 mol/L HCl for 2 h achieved the highest phosphate removal. For the heat-activated red mud, the sample heated at 700 degrees C for 2 h preformed better than the other heat treatment. Phosphate removal by the activated red mud was significantly pH dependent, and pH 7 was the optimal pH for phosphate removal. The adsorption fits Langmuir isotherm model well and the maximum adsorption capacities of the acid-heat activated red mud and the heat activated samples were 202.9 mgP/g and 155.2 mgP/g, respectively.
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http://dx.doi.org/10.1016/s1001-0742(07)60190-9DOI Listing
March 2008

Symptomology and etiology of a new disease, yellow stunt, and root rot of standing milkvetch caused by Embellisia sp. in Northern China.

Mycopathologia 2007 Jun 11;163(6):327-34. Epub 2007 May 11.

College of Pastoral Agriculture Science and Technology, Lanzhou University, Gansu Grassland Ecological Research Institute, P.O. Box 61, Lanzhou, 730020, China.

An Embellisia sp. has been established as the cause of a new disease of the herbaceous perennial forage legume, 'standing milkvetch' (Astragalus adsurgens Pall.) in Northern China, which severely reduces plant density and degrades A. adsurgens stands. The disease was common at an experimental location in Gansu Province where it was recognized by the occurrence of stunted plants with reddish-brown stems and yellow and necrotic leaf blades. An Embellisia sp. was isolated from symptomatic stem, leaf blade, petiole, and root tissues at varying frequencies of up to 90%. Single-spore isolates grew very slowly on PCA, PDA, V-8 and, wheat hay decoction agar. Pathogenicity was confirmed by inoculation of seeds, dipping 2-day-old pre-germinated seedlings in inoculum and spraying inoculum on 6-month-old plants. Symptoms on test plants included yellow leaf lesions, brown lesions on stems and petioles, stunted side-shoots with yellow, small, distorted and necrotic leaves, shoot blight, bud death, crown rot, root rot, and plant death. The disease is named as 'yellow stunt and root rot' of A. adsurgens to distinguish it from diseases caused by other known pathogens. Embellisia sp. is also pathogenic to A. sinicus but not to 11 other tested plant species.
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http://dx.doi.org/10.1007/s11046-007-9002-2DOI Listing
June 2007

[Breakage and regrowth of flocs coagulation with polyaluminum chloride (PACl)].

Huan Jing Ke Xue 2007 Feb;28(2):346-51

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.

The conventional jar test and the monitoring technique of floc size in line were employed to investigate the breakage and regrowth of the flocs formed by PACl. It was found that the breakage and regrowth of flocs varied with coagulation zones. The flocs formed in stabilization zone were of high strength and difficult to break, and could regrow better after broken, with the recovery factor of up to 259%. The flocs formed in charge neutralization zone were of the lowest strength and prone to break, but could reform completely after broken. The flocs formed in restabilization and sweep coagulation zones were also of high strength and difficult to break, but significantly irreversible after broken. The recovery factor of the broken flocs in sweep coagulation zone was only 18.6%. The effects of remixing on the breakage and regrowth of flocs increased with remixing intensity. In sweep coagulation zone, the settling height and mean settling velocity of the interface between flocs blanket and water were lower for the broken and partly reforming flocs than for those unbroken; Moreover, in flocculation settling and zone settling zones, the instantaneous settling velocity of the interface at the same flocs concentration was also lower for the broken flocs than for those unbroken, but in compression settling zone, the instantaneous settling velocity was the same whether the flocs were broken or not.
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February 2007

Performance of a novel vertical-flow settler: a comparative study.

J Environ Sci (China) 2006 ;18(5):858-63

State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.

By increasing particle concentration and G value (root-mean-square velocity gradient) to enhance flocculation, a novel vertical-flow settler was designed to increase sedimentation effectiveness, and to simultaneously improve operational stabilization. Due to the gradual decrease in upward flow-rate of raw water, a flocs blanket would form and suspend in the middle section of the settler, not at the bottom as in a conventional clarifier. Enough large flocs, resulted from flocculation or filtration, would continuously settle out of the flocs blanket, and simultaneously, the flocs in raw water or those forming above the blanket would ceaselessly enter the flocs blanket. As a result, the flocs concentration in the blanket could keep a dynamic balance. The hydrodynamic shear in the blanket was improved by flow separation, which was induced by the abrupt change in flow channel. Due to the floes blanket and improved hydrodynamic shear, flocculation would be enhanced, which was helpful for removing fine particles in raw water. A comparative study showed that the novel vertical-flow settler had a much better performance in the removal of the particles in raw water than a conventional one, when they treated kaolin suspensions of different concentrations (500, 100 and 50 mg/L, respectively) coagulated by polyaluminum chloride(PAC1) at the up-flow rates of I and 2 mm/s, respectively.
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http://dx.doi.org/10.1016/s1001-0742(06)60005-3DOI Listing
March 2007

[The role of adhesion molecules in the pathogenic mechanisms of hypertension in obstructive sleep apnea-hypopnea syndrome].

Zhonghua Jie He He Hu Xi Za Zhi 2004 Aug;27(8):511-4

The State Otolaryngology Institute of Shandong University, Jinan 250012, China.

Objective: To explore the role of adhesion molecules in the pathogenesis of hypertension in obstructive sleep apnea-hypopnea syndrome (OSAHS).

Methods: The levels of serum soluble intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and L-selectin in 30 OSAHS patients accompanied by hypertension, 30 normotensive OSAHS patients and 30 healthy controls were measured by enzyme-linked immunosorbent assay (ELISA) method. The relationship of the concentration of ICAM-1, VCAM-1 and L-selectin with the polysomnogram (PSG) parameters was analyzed.

Results: The levels of serum soluble ICAM-1 [(601 +/- 406) microg/L, (513 +/- 244) microg/L, respectively] and VCAM-1 [(578 +/- 176) microg/L, (480 +/- 144) microg/L, respectively] were significantly higher in OSAHS accompanied by hypertension and normotensive OSAHS than those in the healthy controls [(355 +/- 119) microg/L, (310 +/- 163) microg/L, q = 4.78, 3.07; 9.09, 5.76, P < 0.01, respectively]. But the levels of serum L-selectin was not significantly different among the three groups (P > 0.05). The levels of serum VCAM-1 were significantly higher in OSAHS accompanied by hypertension than those in the normotensive OSAHS (q = 3.32, P < 0.05). The was not significantly different between the two groups (P > 0.05). There was a significantly positive correlation between the concentration of ICAM-1 and the apnea hyponea index (AHI) as well as microarousal index in all the 60 OSAHS patients with and without hypertension (r = 0.465, P < 0.01, r = 0.226, P < 0.05). There was a significantly negative correlation between the concentration of ICAM-1 and the lowest oxygen desaturation in all the 60 OSAHS patients with and without hypertension (r = -0.368, P < 0.01).

Conclusion: The high level of serum VCAM-1 and ICAM-1 is an important risk factor for the development of hypertension in OSAHS patients.
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August 2004

[Evaluation of the serum endothelin-1 level and sleep architecture change in patients with obstructive sleep apnea hypopnea syndrome accompanied hypertension].

Zhonghua Er Bi Yan Hou Ke Za Zhi 2004 Feb;39(2):116-9

State Otorhinolaryngology Institute of China Shandong University, Jinan 250012, China.

Objective: To explore the role of endothelin-1 (ET-1) in the pathogenesis of hypertension in obstructive sleep apnea hypopnea syndrome (OSAHS).

Methods: The levels of serum ET-1 in 30 OSAHS patients accompanied by hypertension, 30 normotensive OSAHS patients and 30 healthy controls were measured by ET-1 enzyme immunoassay kit. Meanwhile the correlation about the concentration of ET-1 in OSAHS patients with the clinic, polysomnography (PSG) parameters was analyzed.

Results: OSAHS patients with or without hypertension compared with snoring group and normal people, the sleep structure was significantly disturbed. The time percentages of awake and stage I sleep were increased, while stage II sleep decreased significantly in OSAHS patients than those in snoring group (P < 0.01, respectively). There were no significantly difference about the sleep structure in the two OSAHS groups. The levels of serum ET-1 (mean +/- s) were significantly higher in OSAHS patients accompanied by hypertension and normotensive OSAHS patients(42.5 +/- 8.4) ng/L and (38.6 +/- 4.7) ng/L respectively than those in the healthy controls(33.1 +/- 5.4) ng/L (P < 0.01, respectively). In the two OSAHS groups, the levels of serum ET-1 were significantly higher in OSAHS patients accompanied by hypertension than those in the normotensive OSAHS patients (P < 0.05). There were positive correlations between the concentration of ET-1 and the apnea hypopnea index (AHI) in all the 60 OSAHS patients with and without hypertension (r = 0.334, P < 0.01). There were negative correlations between the concentration of ET-1 and the lowest oxygen desaturation in all the 60 OSAHS patients with and without hypertension (r = -0.230, P < 0.05).

Conclusion: These results indicate that the sleep disordered breathing and hypoxia may contribute to the elevation of ET-1 in the OSAHS patients and OSAHS patients accompanied by hypertension. ET-1 may play an important role in the pathogenesis of OSAHS-induced hypertension.
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February 2004

[Prevalence survey on Cyclospora cayetanensis and Cryptosporidium ssp. in diarrhea cases in Yunnan Province].

Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi 2002 ;20(2):106-8

Yunnan Center for Disease Control and Prevention, Kunming 650022.

Objective: To investigate the prevalence and distribution characteristics of Cyclospora cayetanensis and Cryptosporidium ssp. infection in diarrhea cases of Yunnan Province.

Methods: To collect fresh faeces from diarrhea cases in 7 counties/cities, examine the specimens by direct smear with iodine staining and modified acid-fast staining.

Results: The infection rate of C. cayetanensis and Cryptosporidium ssp. was 3.97% and 5.29%, respectively. The infection rate of the two pathogenic coccidians was as high as 10.64% and 8.51% in preschool children. C. cayetanensis was found in 3 counties and Cryptosporidium in 6 counties.

Conclusion: Both C. cayetanensis and Cryptosporidium ssp. are prevalent in Yunnan Province with the latter distributed more widely, and the two pathogens are more prevalent in preschool children.
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January 2004
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