Evaluation of the Growth, Sporulation, Fungicide Efficacy, and Host Range of Ramularia sphaeroidea.

Ramularia sphaeroidea was primarily identified based on the characteristics of its conidia and several sequences. The fungus causes severe leaf spot disease on hairy vetch (Vicia villosa var. glabrescens) in Yunnan Province in China. The growth, sporulation, fungicide efficacy, and host range of the pathogen were evaluated to aid in disease management. Different types of culture media and carbon and nitrogen sources were used to evaluate the growth of R. sphaeroidea. Oatmeal, maltose, and potassium nitrate agar had a higher amount of sporulation. Difenoconazole (10%) was the most effective fungicide against the leaf disease caused by R. sphaeroidea. In addition, foliar inoculation sprays were used to assess the host range of R. sphaeroidea in six different plant species, including alfalfa (Medicago sativa L.), sainfoin (Onobrychis viciifolia Scop.), erect milkvetch (Astragalus adsurgens Pall.), common vetch (Vicia sativa L.), red clover (Trifolium pratense L.), and white clover (Trifolium repens L.). R. sphaeroidea successfully infected these plants, indicating that it has a wider host range than hairy vetches.

Germination and Invasion of Paraphoma radicina on Roots of a Susceptible and a Resistant Alfalfa Cultivar (Medicago sativa).

Alfalfa Paraphoma root rot (APRR) (Paraphoma radicina) is a recently described alfalfa disease widely distributed in China, first reported in 2020. So far, the resistance levels of 30 alfalfa cultivars to APRR have been characterized; however, the resistance mechanisms among these cultivars remain unknown. In the present study, the alfalfa resistance mechanisms against APRR were investigated by studying the difference of P. radicina infecting susceptible (Gibraltar) and resistant (Magnum II) alfalfa cultivars under the light microscope and scanning electronic microscope. The conidial germination and germ tube growth in the root exudates of different resistant cultivars were also compared. The results revealed that conidial germination, germ tube development, and P. radicina penetration into root tissues of resistant plants were delayed. In susceptible and resistant cultivars, P. radicina infected roots by penetrating epidermal cells and the intercellular space between epidermal cells. During the infection process, germ tubes penetrated the root surface directly or formed appressoria. However, the penetration percentage on the susceptible cultivar was significantly higher than on the resistant cultivar, irrespective of the infection route. Moreover, disintegrated conidia and germ tubes were observed on resistant cultivar roots at 48 h postinoculation. The conidial germination and germ tube growth in root exudates of susceptible cultivars were significantly higher than in resistant cultivars. The current findings implied that the alfalfa resistance mechanism might be related to root exudates. These findings could provide insights into the alfalfa resistance mechanism following P. radicina infection.

Alternaria gansuense, a Plant Systematic Fungal Pathogen Producing Swainsonine in Vivo and in Vitro.

Astragalus adsurgens (A. adsurgens), which is considered a forage in China, grows widely in Eurasia and North America. However, Alternaria gansuense (A. gansuense) (synonym: Embellisia astragali) systematically infects A. adsurgens, producing swainsonine (SW), which poisons domesticated animals. In this study, we hypothesized that the A. gansuense SW-producing fungus is morphologically and molecularly related to the locoweed endophyte, Alternaria oxytropis (A. oxytropis), which systematically grows in host plants. Therefore, pure cultures of the fungi from diseased plants or endophytic interactions were collected from fields and assayed for SW via high-performance liquid chromatography linked to mass spectroscopy (HPLC-MS). The production of SW was also detected in A. adsurgens, A. oxytropis and diseased plants by assaying for the presence of the ß-ketoacyl synthase (KS) gene, which is required for SW synthesis. Diseased A. adsurgens and pure cultures of A. gansuense have SW and the healthy-looking A. adsurgens plants also contained SW, probably because they were infected with A. gansuense. Therefore, A. adsurgens-infected A. gansuense are not safe for livestock consumption.

Colletotrichum truncatum-A New Etiological Anthracnose Agent of Sword Bean (Canavalia gladiata) in Southwestern China.

Anthracnose is a disease caused by Colletotrichum species. They are well known as major plant pathogens, and a black stem disease, specifically caused by Colletotrichum truncatum and primarily infecting sword bean (Canavalia gladiata), was observed in the Yunnan province, China. To aid disease management and to determine pathogenic characteristics, the species causing the leaf spot disease of hairy vetch was verified as C. truncatum. A sequence analysis of the ITS, ACT, GAPDH, and HIS3 genes was conducted, as well as morphological and cultural characteristics, to identify this Colletotrichum species, which has curved conidia. C. truncatum isolates from sword bean formed a distinctive group among Colletotrichum species, including those that infect other forage and field crops. Artificially inoculated sword bean seedlings showed typical symptoms of anthracnose, which were similar to field observations. To the best of our knowledge, this is the first report of C. truncatum causing black stem disease on sword beans in China.

Effects of timothy Cladosporium eyespot on photosynthesis and biomass.

Timothy is a forage mainly grown in Min County, Gansu Province, China. In 2021, a leaf spot disease outbreak on timothy grass occurred in Min County, adversely affecting its growth and productivity. Therefore, this study investigated the leaf spot disease incidence in Min County, morphologically and molecularly characterized the disease-causing pathogen, and assessed its effects on the growth, photosynthesis, and biomass of timothy seedlings re-inoculated with the isolated pathogen. In the field, the disease incidence on plants and leaves was 100 and 85%, respectively. Morphologically, young lesions were ellipsoidal-fusiform with dark purple margins and an off-white center, while the mature lesions were eye-shaped spots with a light brown center and dark purple edges. Molecular characterization identified the pathogen as Cladosporium phlei causing Cladosporium eyespot disease. The net photosynthetic rate, transpiration rate, fresh shoot weight, and dry shoot weight of timothy seedlings 14 days after inoculation with the pathogen were decreased by 29.77, 56, 45.45, and 46.42%, respectively, implying that Cladosporium eyespot disease is an important timothy grass disease in Min County. Therefore, developing an integrated control strategy is urgent to lessen the economic loss.

The Characterization and the Biological Activity of Phytotoxin Produced by Paraphoma radicina.

Paraphoma radicina is a new pathogen that causes alfalfa paraphoma root rot (APRR), leading to alfalfa production losses. The resistance levels of 30 alfalfa cultivars to APRR have already been characterized. However, the pathogenic mechanism of P. radicina is still unclear. This study aimed to assess the effects of a crude toxin extracted from P. radicina cell-free culture filtrate (CFCF) on susceptible and resistant cultivars of alfalfa. Meanwhile, the crude toxin components were detected using gas chromatography-mass spectrometry (GC-MS) analysis. CFCF cultured in MEB medium for 14 days and crude toxin extracted by ethyl acetate induced significant phytotoxicity caused the average lesion areas of 5.8 and 3.9 mm2, respectively, on alfalfa leaves. The crude toxin exhibited resistance to high temperature, as shown by a lesion area of 3.6 mm2 when treated at 120 °C for 30 min. Different concentrations of the crude toxin in water and MS medium had different effects on susceptible and resistant cultivars. Moreover, the crude toxin affected the plasma membrane, mitochondria, and nuclear membranes of alfalfa root cortical cells. Further, it induced significant phytotoxicity on Sonchus oleraceus L., Capsella bursa-pastoris (Linn.) Medic, and Chenopodium album L. Agropyron cristatum L. (average lesion areas; 11.6, 15.8, 21.4, and 6.2 mm2, respectively), indicating that the crude toxin of P. radicina is a non-host-selective toxin. GC-MS analysis detected four possible active substances in the toxin (3-hydroxypyridine, 5-methylresorcinol, 3-Hydroxypropionic acid, and 4-Hydroxyphenylethanol). Therefore, this study may provide insight into the pathogenic mechanism of P. radicina to alfalfa.

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

Hairy vetch Vicia villosa Roth is widely grown in southwestern China for green manure and forage. In December 2019, a leaf disease occurred on 80% plants of V. villosa var. glabrescens 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), tef1-α, his3 and gapdh 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), tef1-α (MW448172 to MW448174), his3 (MW448175 to MW448177), and gapdh (MW448178 to MW448180). These sequences had the highest similarities with sequences of Ramularia sphaeroidea Sacc. in GenBank, 99%(514∕516, 515∕517, and 514∕517 bp) for ITS, 99% (402∕403, 403∕405, and 405∕405bp) for tef1-α, 99% (377∕378, 378∕378, and 376∕378bp) for his3, and 100% (558∕557, 557∕559 and 561∕565 bp) for gapdh . A phylogenetic tree generated with the sequences clustered the fungus closely with R. sphaeroidea. Infection experiments were carried out with 50 plants of V. villosa var. glabrescens 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. R. sphaeroidea has been reported on V. fabae and V. sativa in Ethiopia and Israel (Braun 1998), on various Vicia species including V. villosa in California, the United States (Koike et al. 2004) and on V. craccain China (Zhang et al. 2006), but to our knowledge, this is the first report of this fungus causing leaf spot on V. villosa in China.

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

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.

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

OBJECTIVE: To expound the roles of mTOR and NF-kB signaling pathway in intermittent hypoxia (IH)-induced damage of hippocampal neurons. METHODS: 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, IKKß, BDNF, TNF-α, IL-1ß, PSD-95 and SYN in hippocampal neurons were examined. RESULTS: Compared with normal control rats or neurons, IH-treated group had elevated expression levels of NF-kB, TNF-α and IL-1ß and suppressed expression level of BDNF, PSD-95 and SYN. These results were reversed upon pre-treatment with Rapa and PDTC. Furthermore, IκBα and IKKß 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. CONCLUSION: 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.

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

Verticillium wilt caused by Verticillium alfalfae 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 Verticillium 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 V. alfalfae, with a high virulence to milkvetch, sainfoin, and stylo. This study confirmed that V. alfalfae has become established in some regions of Gansu, China and that is a risk to the alfalfa industry in China.

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

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.

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

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.

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

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.

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

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.

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

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).

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

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.

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

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

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.

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

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.

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

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.