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Spent mushroom substrate (SMS) is the by-products of mushroom production, which is mainly composed of disintegrated lignocellulosic biomass, mushroom mycelia and some minerals. The huge output and the lack of effective utilization methods make SMS becoming a serious environmental problem. In order to improve the application of SMS and SMS derived biochar (SBC), composted SMS (CSMS), SBC, combined plant growth-promoting rhizobacteria (PGPR, Bacillus subtilis BUABN-01 and Arthrobacter pascens BUAYN-122) and SBC immobilized PGPR (BCP) were applied in the lettuce seedling. Seven substrate treatments were used, including (1) CK, commercial control; (2) T1, CSMS based blank control; (3) T2, T1 with combined PGPR (9:1, v/v); (4) T3, T1 with SBC (19:1, v/v); (5) T4, T1 with SBC (9:1, v/v); (6) T5, T1 with BCP (19:1, v/v); (7) T6, T1 with BCP (9:1, v/v). The physicochemical properties of substrate, agronomic and physicochemical properties of lettuce and rhizospheric bacterial and fungal communities were investigated. The addition of SBC and BCP significantly (p < 0.05) improved the total nitrogen and available potassium content. The 5% (v/v) BCP addiction treatment (T5) represented the highest fresh weight of aboveground and underground, leave number, chlorophyll content and leaf anthocyanin content, and the lowest root malondialdehyde content. Moreover, high throughput sequencing revealed that the biochar immobilization enhanced the adaptability of PGPR. The addition of PGPR, SBC and BCP significantly enriched the unique bacterial biomarkers. The co-occurrence network analysis revealed that 5% BCP greatly increased the network complexity of rhizospheric microorganisms and improved the correlations of the two PGPR with other microorganisms. Furthermore, microbial functional prediction indicated that BCP enhanced the nutrient transport of rhizospheric microorganisms. This study showed the BCP can increase the agronomic properties of lettuce and improve the rhizospheric microbial community.
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Introduction: Broken eggs are a byproduct of the poultry industry and a potential nitrogen source for mushroom cultivation. However, its feasibility needs to be evaluated experimentally. Methods: In this study, a series of different addition amounts (0, 1.8, 3.6, 5.3 and 8.5%, w/w) of broken egg mixture (BEM) were applied in the composting cultivation process of oyster mushroom. The physicochemical properties and bacterial communities of composting substrate, and agronomic and nutritional properties of fruiting bodies were determined. Results and discussion: The results showed that the BEM addition significantly (P < 0.05) increased the total nitrogen content in the composted substrate, and the contents of crude protein, total amino acids and essential amino acids of mushrooms. The P3 treatment (initial C/N of 26:1) showed the highest biological efficiency (BE) of 100.19% and a low contamination rate (CR) of 7.00%, while the higher dosage of BEM (P4 and P5) led to a sharp decrease in BE and a sharp increase in CR. High throughput sequencing revealed that the addition of BEM significantly (P < 0.05) changed the bacterial communities in the substrate at the beginning of composting. Streptococcus and Lactococcus were predominant bacterial genera in BEM treatments at the beginning stage of composting, while Acinetobacter became predominant at the ending stage. The co-occurrence network analysis showed that the P3 treatment demonstrated a much more complex bacterial community. The structural equation model analysis indicated that the addition of BEM affected the bacterial communities and nitrogen metabolism during composting, which further affected agronomic and nutritional properties of oyster mushrooms. An appropriate amount of BEM combined with composting processes can significantly improve the yield and quality of oyster mushroom, providing a new way for efficient utilization of BEM.
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Objective: To analyze the clinical features and genetic characteristics of two patients with hereditary hemorrhagic telangiectasia (HHT) and to review the relevant literature. Methods: The clinical data of two HHT patients admitted to the author's hospital between April 2019 and February 2022 were retrospectively analyzed. Meanwhile, the genetic analysis was performed with their consent. Results: The first patient was a 62-year-old woman who had been complaining of shortness of breath and fever for 20 days. Her previous medical history included brain abscess drainage and video-assisted thoracoscopic surgery for a pulmonary hemangioma. A right heart catheterization revealed no pulmonary arterial hypertension, and an abdominal enhanced magnetic resonance imaging revealed multiple arteriovenous malformations in the liver. Her ACVRL1 heterozygous variants were discovered through whole-exon gene testing. The second case involved a 47-year-old woman who had been experiencing chest tightness for the past 2 years. Several years ago, she underwent brain abscess drainage and embolization of a pulmonary arteriovenous fistula. Ultrasound revealed generalized hepatic vascular dilation, and enhanced computed tomography revealed numerous pulmonary venous fistulas scattered in both lungs as well as multiple arteriovenous malformations in the liver. Her whole-exon gene testing revealed that she, like her son, had heterozygous ENG variants. Conclusion: HHT patients may experience infection, bleeding, dyspnea, and other symptoms. Imaging is important in disease diagnosis and management because early detection and treatment can prevent major complications and disability or even death.
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A short-term composting process to prepare substrate is an effective way to cultivate oyster mushrooms (Pleurotus spp.), which can increase the yield of mushrooms and lower the rate of contamination in non-industrialized cultivation. Moreover, it is different from the traditional composting processes for fertilizers and lacks systematic study, such as microbial succession and compost quality. In this study, a series of different tests of composting duration (0, 2, 4 and 5 d) were performed. A composting duration of 4-5 d over 58 °C was suitable for mushroom cultivation based on the biological efficiency (BE) range of 69.76-73.41 % and the contamination rate of 0 %. The content of total carbon (TC) continuously decreased during composting, while the content of total nitrogen (TN) reacted in an opposite matter. The final TN and C/N ratios were 1.89 % and 28/1, respectively, which fell well within the optimal range of nutritional requirements for oyster mushroom cultivation. The composting bacteria were more diverse than the fungal species. Caldibacillus, Thermobispora, Thermopolyspora, Thermobacillus and Ureibacillus were the predominant bacterial genera during the thermophilic stage. Co-occurrence patterns of microbial communities and physicochemical properties were performed using a network analysis, which indicated that bacteria can play more efficient roles than fungi in the degradation of organic matter. The structural equation model showed that composting duration significantly affected bacterial diversity, lignocellulose degradation rates, and BE. The correlations between bioinformatics parameters with composting characters and agronomic traits were determined by the Mantel test and showed that the induction of bacterial diversity over time rapidly activated carbon metabolism during short-term composting. This study provides a new idea of agro-waste composting for mushroom cultivation.
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Agaricales , Compostagem , Microbiota , Pleurotus , Bactérias/metabolismo , Carvão Vegetal/metabolismo , Fertilizantes/análise , Nitrogênio/análise , Pleurotus/metabolismoRESUMO
Wetlands are an important global source and sink of methane. However, human activities and climatic conditions are causing serious degradation of wetlands in China. In response to this, the relevant departments have progressively carried out wetland restoration projects over the past few years. To investigate the response of microbial communities of bacteria, methanogens, and methanotrophs during degradation and restoration of wetlands, soil samples were collected from undegraded reed wetlands, degraded reed wetlands, and restored reed wetlands in the Songnen Plain. Microbial diversity and community composition were studied by high-throughput sequencing based on the 16S rRNA gene of bacteria, the mcrA gene of methanogens, and the pmoA gene of methanotrophs. The results indicate that the degradation of reed wetlands results in a decrease in bacterial and methanogenic α-diversity and an increase in methanotrophic α-diversity. Bacterial α-diversity and methanogenic α-diversity were both significantly positively correlated with soil water content. At different taxonomic levels, higher relative abundances of Rhizobiales and Methanobacteriaceae were detected in the undegraded wetland soils. Wetland degradation decreased the relative abundance of Rhizobiales but increased that of the pathogenic bacteria Burkholderiaceae and microorganisms resistant to harsh and extreme environments including Sphingomonas, Rubrobacter, Methylobacter, Methylomonas, and Methylococcus. In the restored wetland soils, the relative abundances of Bacillus, Methanosarcinaceae, Methanomicrobiaceae, and the type â ¡ methanotroph Methylocystis were higher. Therefore, different wetland conditions can indirectly change soil properties and, consequently, change the community structure of methanogens and methanotrophs.
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Microbiota , Áreas Alagadas , Humanos , Metano , Filogenia , RNA Ribossômico 16S , Solo , Microbiologia do SoloRESUMO
An extracellular laccase (GLL) was purified from fermentation broth of the litter-decomposing fungus Gymnopus luxurians by four chromatography steps, which resulted in a high specific activity of 118.82 U/mg, purification fold of 41.22, and recovery rate of 42.05%. It is a monomeric protein with a molecular weight of 64 kDa and N-terminal amino acid sequence of AIGPV TDLHI, suggesting that GLL is a typical fungal laccase. GLL demonstrated an optimum temperature range of 55°C-65°C and an optimum pH 2.2 toward 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). It displayed considerably high thermostability and pH stability with about 63% activity retained after 24 h at 50°C, and 86% activity retained after 24 h at pH 2.2, respectively. GLL was significantly enhanced in the presence of K+, Na+, and Mg2+ ions. It demonstrated K m of 539 µM and k cat /K m of 140 mM-1â s-1 toward ABTS at pH 2.2 and 37°C. Acetosyringone (AS) and syringaldehyde (SA) were the optimal mediators of GLL (0.4 U/ml) for dye decolorization with decolorization rates of about 60%-90% toward 11 of the 14 synthetic dyes. The optimum reaction conditions were determined to be mediator concentration of 0.1 mM, temperature range of 25°C -60°C, and pH 4.0. The purified laccase was the first laccase isolated from genus Gymnopus with high thermostability, pH stability, and effective decolorization toward dyes, suggesting that it has potentials for textile and environmental applications.
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In this study, a novel process combining partial denitrification (PD, NO3--NâNO2--N) and denitrifying phosphorus removal (DPR) in an anaerobic-anoxic-aerobic sequencing batch reactor (SBR) was developed. By comprehensively controlling the influent C/N ratio, anaerobic drainage ratio, and anoxic duration, the nitrite accumulation and phosphorus removal performance of a system treating high-strength nitrate and municipal wastewaters was investigated. The results showed that, after 140 days, the nitrate-to-nitrite transformation ratio (NTR) was 80.1%, and PO43--P removal efficiency was 97.64%. In the anaerobic stage (180 min), glycogen-accumulating organisms (GAOs) and phosphorus-accumulating organisms (PAOs) efficiently utilized the carbon source in municipal wastewater to enhance intracellular carbon storage. In the anoxic stage (150 min), denitrifying GAOs (DGAOs) and heterotrophic denitrifying bacteria (DOHOs) carried out endogenous and exogenous short-range denitrification, respectively, to achieve stable nitrite accumulation; simultaneously, denitrifying PAOs (DPAOs) carried out denitrifying phosphorus uptake to achieve efficient phosphorus removal. In the aerobic stage (10 min), without initiating ammonia/nitrite oxidation, PAOs absorbed excessive phosphorus, which improved the phosphorus removal performance of the system. The effluent NO2--N/NH4+-N of a ratio of 1.31:1 (close to the theoretical value of ANAMMOX process, 1.32:1), with little PO43--P and COD (0.30 and 12.94 mg·L-1), meets the requirements for deep-level nitrogen removal by coupling with ANAMMOX process.
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BACKGROUND: This study aimed to observe the hypoglycemic effect of cassia seed extract in rats with type-2 diabetes mellitus and its effect on reducing insulin resistance in the skeletal muscle. METHODS: 50 rats were randomly divided into the normal, model, high-dose, middle-dose, and low-dose groups of cassia seed extract (n = 10 each). A high-fat diet combined with streptozotocin administration was adopted to build type 2 diabetes models. The cassia seed extract groups were fed different concentrations cassia seed extract while the normal and model groups were fed the same volume of normal saline. The weight, FINS, GIR, insulin tolerance, blood glucose and blood lipid level, oxidative stress indices and expressions related to the LKB1-AMPK-GLUT4 pathway were detected and compared between the two groups. RESULTS: Compared with the normal group, the model group showed lower weight, glucose infusion rate and expressions related to LKB1-AMPK-GLUT4 pathway and higher FINS, insulin tolerance, blood glucose and blood lipid level and oxidative stress indices (all P < 0.05). Compared with the model group, higher weight, glucose infusion rate and expressions related to LKB1-AMPK-GLUT4 pathway and lower FINS, insulin tolerance, blood glucose and blood lipid level and oxidative stress indices were observed in all groups that were administered cassia see extract (all P < 0.05). CONCLUSION: Cassia seed extract could noticeably improve the insulin resistance of diabetic rats and enhance the insulin sensitivity of their skeletal muscles. Its mechanism may be related to damage repair of the LKB1-AMPK-GLUT4 signaling pathway and oxidative stress in the skeletal muscle.
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In this study, we examined the association between soy isoflavones and lipid profiles, apolipoprotein levels in patients with type 2 diabetes in China. The study population was composed of 120 cases (80 women with type 2 diabetes and 40 healthy women). Objects in treatment group received isoflavones 435 mg/day for 2 months, then lipid profiles were analyzed by the colorimetry method and apolipoprotein levels were determined by immune turbidimetric method. And all the indexes were determined after oral glucose tolerance test. The levels of total cholesterol, triglyceride and LDL-C significantly reduced and the levels of HDL-C and apolipoprotein A1 significantly raised in the treatment group after intervention (p<0.05). After oral glucose tolerance test, the level of total cholesterol was lower at postprandial 6 h than at empty stomach in treatment group, it had significantly difference (p<0.05). LDL-C levels in the treatment group not only decreased after intervention, but also was significantly lower at postprandial 4, 6 h than in non-intervention group. The ratio of apolipoprotein A1/apolipoprotein B at postprandial 2 h was the highest after treatment in isoflavone group. Supplementation with 435 mg/day of isoflavones exerted favorable effect on the blood total cholesterol, LDL-C levels and the ratio of apolipoprotein A1/apolipoprotein B in Chinese type 2 diabetes women.
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Gravity matching navigation algorithm is one of the key technologies for gravity aided inertial navigation systems. With the development of intelligent algorithms, the powerful search ability of the Artificial Bee Colony (ABC) algorithm makes it possible to be applied to the gravity matching navigation field. However, existing search mechanisms of basic ABC algorithms cannot meet the need for high accuracy in gravity aided navigation. Firstly, proper modifications are proposed to improve the performance of the basic ABC algorithm. Secondly, a new search mechanism is presented in this paper which is based on an improved ABC algorithm using external speed information. At last, modified Hausdorff distance is introduced to screen the possible matching results. Both simulations and ocean experiments verify the feasibility of the method, and results show that the matching rate of the method is high enough to obtain a precise matching position.
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Algoritmos , Inteligência Artificial , Tecnologia/métodos , GravitaçãoRESUMO
In order to obtain the lead compound for treatment of rheumatoid arthritis (RA), in this study, therapeutic efficacy of three bispecific antibodies (BsAB-1, BsAB-2 and BsAB-3) against both hIL-1beta and hIL-17 were compared on CIA model mice. First, by ELISA method we compared the binding capacity of the three bispecific antibodies to the two antigens. The results showed that all three antibodies could simultaneously bind both antigens, among these antibodies, BsAB-1 was superior over BsAB-2 and BsAB-3. CIA model was established with chicken type II collagen (CII) and developed RA-like symptoms such as ankle swelling, skin tight, hind foot skin hyperemia. The CIA mice were treated with three antibodies once every two days for total of 29 days. Compared with the CIA model mice, the RA-like symptoms of the antibody treated-mice significantly relieved, while the BsAB-1 treated-mice were almost recovered. CII antibody level in the serum and cytokines (IL-2, IL-1beta, IL-17A and TNF-alpha) expression in the spleen were examined. Compared with the CIA model mice, all three antibodies could significantly reduce CII antibody and cytokine expression levels. BsAB-1 antibody was more potent than BsAB-2 and BsAB-3. In summary, BsAB-1 is superior over BsAB-2 and BsAB-3 in amelioration of RA symptoms and regulation of CII antibody production and pro-inflammatory cytokine expression, therefore, BsAB-1 can be chosen as a lead compound for further development of drug candidate for treatment of RA.
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Anticorpos Biespecíficos/uso terapêutico , Artrite Experimental/terapia , Artrite Reumatoide/terapia , Animais , Anticorpos/metabolismo , Anticorpos Biespecíficos/imunologia , Reações Antígeno-Anticorpo , Artrite Experimental/induzido quimicamente , Artrite Experimental/metabolismo , Artrite Reumatoide/induzido quimicamente , Artrite Reumatoide/metabolismo , Colágeno Tipo II/imunologia , Interleucina-17/metabolismo , Interleucina-1beta/metabolismo , Interleucina-2/metabolismo , Masculino , Camundongos , Baço/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
There are more than 50 000 workers in Jinchuan Group Co, Ltd (JNMC). Since all staff in JNMC are eligible for a medical examination every two years, only 23 484 nickel-exposed subjects who participated in medical examination were included in this study. Their data, collected from June 22, 2011 to September 28, 2012, in a comprehensive epidemiological survey and during medical examinations, permitted an extensive evaluation of the relation between metal exposure, gene, epigenetics and risk of human diseases. Their lifestyle investigation showed that the overall prevalence of current smokers, alcohol drinkers, and tea drinkers was 39.1%, 19.7%, and 55.2%, respectively. The prevalence of hypertension, allergic rhinitis and cholecystitis , the top 3 prevalent diseases, was 11.7%, 11.0%, and 8.9%, respectively.
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Hipertensão/epidemiologia , Neoplasias/epidemiologia , Níquel/toxicidade , Exposição Ocupacional/estatística & dados numéricos , Adulto , Idoso , Consumo de Bebidas Alcoólicas/epidemiologia , Biomarcadores Tumorais/análise , China/epidemiologia , Colecistite/epidemiologia , Estudos de Coortes , Feminino , Humanos , Hipertensão/etiologia , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Neoplasias/etiologia , Neoplasias/mortalidade , Rinite Alérgica , Rinite Alérgica Perene/epidemiologia , Fumar/epidemiologia , Adulto JovemAssuntos
Lesão Pulmonar Aguda/induzido quimicamente , Compostos Organometálicos/toxicidade , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/patologia , Animais , Proteína Quinase CDC2/genética , Proteína Quinase CDC2/metabolismo , Ciclo Celular/efeitos dos fármacos , Quinase 1 do Ponto de Checagem , Feminino , Pulmão/metabolismo , Pulmão/patologia , Pulmão/ultraestrutura , Masculino , Malondialdeído/metabolismo , Microscopia Eletrônica de Transmissão , Estresse Oxidativo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To assess the curative effects of different drugs on liver cell damage of rats induced by acute nickel carbonyl poisoning. METHODS: In present study 220 SD rats were divided into control group (10 rats), carbonyl nickel group (10 rats), 20 mg/kg methylprednisolone group (40 rats), 100 mg/kg DDC group (40 rats), 10 µmol/kg sodium selenite group (40 rats), 0.25 ml shenfuhuiyangtang group (40 rats) and 20 mg/kg methylprednisolone with 100 mg/kg DDC group (40 rats). All rats except for control group inhaled passively 250 mg/m(3) carbonyl nickel for 30 minutes. At 4h and 30h after exposure, the drugs were given intraperitoneally to the rats. On the 3rd and 7th days after exposure, the liver samples were taken from 10 rats each group. The DNA damage of liver cells was detected using comet assay, the ultrastructure changes in liver cells were examined under an electronmicroscope. RESULTS: Compared to carbonyl nickel group, the tail lengths of liver cells in 5 groups administrated at 4 h or 30 h and tested on the 3rd or 7th day after exposure decreased significantly (P < 0.05). Compared to the control group, the tail lengths of liver cells in sodium selenite and shenfuhuiyangtang groups administrated at 4h after exposure or sodium selenite, shenfuhuiyangtang and methylprednisolone with DDC groups administrated at 30h after exposure increased significantly (P < 0.05 or P < 0.01), when tested on the 3rd day after exposure. Except from methylprednisolone sub-group administrated at 4h and tested on the 7th day after exposure, the tail lengths of liver cells in other groups administrated at 4 h or 30 h and tested on the 7th day after exposure increased significantly (P < 0.05). Compared to carbonyl nickel group, the Olive moment of liver cells in 5 groups administrated at 4 h or 30 h tested on the 3rd or 7th day after exposure decreased significantly (P < 0.05 or P < 0.01). Compared to the control group, the Olive moment of liver cells in following groups (selenite and shenfuhuiyangtang groups administrated at 4 h or 30 h and tested on the 3rd or 7th day after exposure, DDC group administrated at 4 h or 30 h and tested on the 7th day after exposure, DDC group administrated at 30h and tested on the 3rd day after exposure, and methylprednisolone with DDC group administrated at 30 h and tested on the 7th day after exposure) increased significantly (P < 0.05 or P < 0.01). As compared with carbonyl nickel group, the ultrastructure observation indicated that the nucleus and other organelles of liver cells in methylprednisolone, DDC and methylprednisolone with DDC groups administrated at 4h and tested on the 3rd day were access to normal levels. CONCLUSION: The results of present study showed that methylprednisolone, DDC and methylprednisolone with DDC could improve obviously the repair of rat liver cell damage induced by acute carbonyl nickel poisoning, and the curative effects of early treatment were better than those of later treatment.
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Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Hepatócitos/patologia , Metilprednisolona/uso terapêutico , Compostos Organometálicos/intoxicação , Zalcitabina/uso terapêutico , Animais , Doença Hepática Induzida por Substâncias e Drogas/patologia , Dano ao DNA , Medicamentos de Ervas Chinesas/uso terapêutico , Masculino , Ratos , Ratos Sprague-Dawley , Selenito de Sódio/uso terapêuticoRESUMO
OBJECTIVE: To investigate the submerged culture conditions and nutritional requirments for the production of mycelial biomass and exopolysaccharides (EPS) by medicinal mushroom Phellinus baumii. METHOD: The carbon sources, nitrogen sources, inoculum volume, initial pH and temperature were investigated based on shake flask cultures, respectively. RESULT: The glucose was the most suitable carbon source for both mycelial biomass and EPS production, soy peptone was favorable nitrogen sources for both mycelial biomass and EPS production. The optimal inoculum volume, initial pH and temperature for both mycelial growth and EPS production were 6%, 6.0 and 28 degrees C, respectively. CONCLUSION: The study obtained basic datas for large-scale submerged culture of P. baumii.
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Basidiomycota/crescimento & desenvolvimento , Basidiomycota/metabolismo , Biomassa , Micélio/crescimento & desenvolvimento , Micélio/metabolismo , Polissacarídeos/biossíntese , Concentração de Íons de Hidrogênio , TemperaturaRESUMO
OBJECTIVE: To breed good strains by protoplast fusion in Phellinus baumii. METHODS: 5.8S rDNA-ITS sequences, mycelial growth rate, mycelial biomass and exopolysaccharides (EPS) production of 7 strains in different origins were analyzed, respectively. Then the inactivated parent protoplast and the PEG induction were used in the process of protoplast fusion. RESULTS: The strain P. baumii SA02 and P. baumii SA04 were selected as the parent strains. R002, R003 and R005 had antagonistic effects with parent strains. CONCLUSION: R002, R003 and R005 are fusants of the parent strains.
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Basidiomycota/crescimento & desenvolvimento , Micélio/crescimento & desenvolvimento , Protoplastos , Basidiomycota/metabolismo , Biomassa , Fermentação , Micélio/metabolismo , Polissacarídeos/biossínteseRESUMO
An isothermal batch experiment was conducted in the laboratory to compare adsorption of bacteriophages MS2 and phiX174 onto 6 different soils (red loam soil, red clay soil, wushan soil, huangni soil, sandy fluvo-aquic soil and loamy fluvo-aquic soil) in China. Soils with sterilized or non-sterilized treatment were used. Relative coefficients of each numerical simulation of the isotherms using three models were evaluated. The results show that the properties of the soil and virus, and presence/absence of the soil autochthonous microorganisms have pronounced effect on the virus adsorption. Both MS2 and phiX174 are almost completely adsorbed by the red clay soil, but minimal adsorption is observed in the two fluvo-aquic soils. Adsorption of phiX174 to all the non-sterilized soils is generally much greater than that of MS2, while sterilization leads to opposite results. Freundlich and Langmuir isotherms are found to have better coefficients to simulate the apparent steady-state virus concentrations. Freundlich isotherm is capable of demonstrating the effect of virus concentration on adsorption behavior. Langmuir isotherms can be used to compare relative adsorption among treatments, while the present study suggests that maximum adsorption can not be calculated when using the Langmuir isotherms.
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Bacteriófago phi X 174/isolamento & purificação , Levivirus/isolamento & purificação , Microbiologia do Solo , Solo/análise , Adsorção , Bacteriófago phi X 174/crescimento & desenvolvimento , China , Cinética , Levivirus/crescimento & desenvolvimento , TermodinâmicaRESUMO
The presence of air-water interface in batch sorption experiments may result in inaccurate estimation of virus adsorption onto various soils. A batch sorption experiment was conducted to compare the adsorption results of MS2 in different soils under presence/absence of air-water interface. Soils with sterilization/nonterilization treatment were used. Virus recovery efficiency in a blank experiment (no soil) was also evaluated as affected by different amount of air-water interface. The presence of air-water interface altered the results of virus adsorption in different soils with different extent, with Sandy fluvo-aquic soil being the most considerably affected, followed by Red loam soil, and the least being Red clay soil, probably because of different soil properties associated with virus adsorption/inactivation. Soil sterilization resulted in more significant difference of virus adsorption onto the Sandy fluvo-aquic soil between the presence and absence of air-water interface, while a reduced difference was observed in the Red loam soil. The presence of air-water interface significantly decreased virus recovery efficiency, with the values being decreased with increase in the amount of air-water interface. Soil particles likely prohibit viruses from reaching the air-water interface or alter the forces at the solid-water-air interface so that the results from the blank experiment did not truly represent results from control blank, which probably resulted in adsorption difference between presence and absence of the air-water interface.
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Ar/análise , Levivirus/isolamento & purificação , Microbiologia do Solo , Água/análise , Adsorção , Movimentos do Ar , Silicatos de Alumínio , Argila , Solo/análise , Propriedades de Superfície , Movimentos da ÁguaRESUMO
OBJECTIVE: To isolate and identify the phenotype and biological characteristics of pancreas derived mesenchymal stem cell. METHODS: Fresh pancreas of 4-5 months old aborted fetus was dissected free from connective tissue, and was cut into small pieces. The adherent cells were harvested and subcultured, after the third subculture, the cells were used for examination. Cell cycle was analyzed by measuring DNA content by FACScan flow cytometer. Phenotype of MSCs was analyzed by immunohistochemical SA technique and differentiated cells were identified by relevant specific staining. RESULTS: Fetal pancreas derived cells gave rise to a population of adherent cells characterized by the presence of a predominant cell type with a typical fibroblast like morphology. By transmission electron microcopy, MSC had few endoplasmic reticulums and mitochondrias. During the log phase of growth, MSC proliferated with a two fold population at 30 h. MSC can be ex vivo expanded by successive cycles of trypsinization, seeding, and culture. Under these conditions, MSC had capability of passaging up to 30 times without displaying significant changes in morphology, with 2-fold increase in cell number after each passage. This indicates the high ex vivo expansion potential of MSC. The results showed that the yield of CFU-Fs was above 200 clones even after the 6th passage. Cell cycle analysis by flow cytometry revealed that more than 83% of cells were in the G0/G1 phases, while a small population of cells were actively engaged in proliferation (S + G2 + M = 17%). We also showed that more than 86% of cells were positive stained by FITC labeled CD44, CD29, CD13, and only about 1% of cells were positive for CD34, HLA-DR. Expression of collagen I, III was positive while vWF was negative. In the differentiation study, we found culture-expanded pancreas MSCs could be directed into the osteogenic lineage as detected by osteoblastic morphology, expression of alkaline phosphatase, modulation of osteocalcin mRNA production and the formation of a mineralized extracellular matrix. We also found that MSCs could give rise to the adipogenic and chondrogenic lineage as evidenced by accumulation of lipid-rich vacuoles within cells and the expression of lipoprotein lipase mRNA or the expression of collagen II and the deposition of proteoglycans. CONCLUSION: Mesenchymal stem cells existing in human pancreas can be isolated by their adherent ability and should be essential to sustain a steady supply of primitive cells in tissue remodeling.