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1.
Front Immunol ; 13: 984697, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36203614

RESUMEN

Background: The human leukocyte antigen (HLA) susceptibility gene is the main genetic risk factor for primary biliary cholangitis (PBC). The prognosis of patients with PBC is linked to gut microbiota dysbiosis. However, whether the HLA alleles are associated with the gut microbiota distribution and disease severity remains unknown. Methods: A cohort of 964 Chinese patients with PBC was enrolled at Beijing YouAn Hospital, Beijing, China. High-resolution genotyping of the HLA class I and class II loci from 151 of these patients was performed using sequence-based PCR. Stool samples were collected from 43 of the 151 fully HLA-typed patients to analyze their microbiota compositions via 16S RNA gene sequencing. Results: Of the 964 patients, the male:female ratio was 114:850, and 342 of these patients (35.5%) had already developed liver cirrhosis (LC) before enrollment. Patients with PBC showed a significantly higher frequency of HLA DRB1*08:03 than did the controls (21.2% vs. 9.0%, P=0.0001). HLA-DRB1*03:01, DRB1*07:01, DRB1*14:05, and DRB1*14:54 frequencies were also increased but did not reach significance after Bonferroni's correction. Conversely, the DQB1*03:01 frequency was significantly lower in patients with PBC than in the controls (24.5% vs. 39.2%, P=0.0010). The patients' gut microbiota were analyzed from four perspectives. The microbial community abundances were significantly lower in FHRAC-positive patients (patients with a combination of five HLA DRB1 high-risk alleles) than in FHRAC-negative patients (P<0.05). Of the top 10 microbial genera, Lachnospiraceae_incertae_sedis was higher in the FHRAC-positive patients than in the FHRAC-negative patients (P<0.05). linear discriminant analysis (LDA) effect-size (LEfSe) analysis showed different microbes at different levels in the FHRAC-negative patients but not in the FHRAC-positive patients. DQB1*03:01-positive patients contained mostly Lactobacillaceae at the family level. A comparison of the FHRAC-positive patients with and without liver cirrhosis showed that the abundances of Veillonella were significantly higher in patients with cirrhosis and FHRAC than in those without cirrhosis and are FHRAC-negative. Conclusion: The HLA class II genes may influence the gut microbiota compositions in patients with PBC. Differential gut microbiota were expressed at different taxonomic levels. Some bacterial abundances may be increased in FHRAC-positive patients with PBC and cirrhosis.


Asunto(s)
Microbioma Gastrointestinal , Cirrosis Hepática Biliar , Femenino , Microbioma Gastrointestinal/genética , Genes MHC Clase II , Antígenos HLA/genética , Cadenas HLA-DRB1/genética , Humanos , Cirrosis Hepática Biliar/genética , Masculino , ARN
2.
Front Immunol ; 13: 1098076, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36685575

RESUMEN

Background: A variety of autoantibodies have been detected in primary biliary cholangitis (PBC), while the presence of autoantibody clusters and their clinical significance have not been fully understood. We aimed at defining autoantibody clusters and to better understand the clinical features and prognosis of PBC patients based on autoantibody clusters under real-world conditions. Methods: We retrospectively analyzed 788 inpatients with PBC evaluated between October 2008 and July 2019, and included 537 patients. Nineteen autoantibodies which were measured routinely were investigated for cluster analysis. Two-step clustering, Kaplan-Meier survival, and Cox regression analyses were used. Results: Five clusters were defined. A cluster of antinuclear antibodies (ANA) and anti-gp210 positive patients were identified with a high rate of cirrhosis at baseline and low survival rate; a cluster of ANA, anti-centromere antibodies (ACA) and/or anti-CENP-B female dominant patients with older disease onset, low level of platelet count at baseline, high rate of hepatic decompensation, and low survival rate was also characterized; and another cluster of anti-mitochondrial antibodies (AMA) and/or AMA-M2, anti-Ro52 and a high rate of anti-gp210 positive patients were identified with a high proportion of male patients and low survival rate. A subgroup of patients with anti-SSA and/or anti-SSB coexists with SjS was also identified; patients with only AMA and/or AMA-M2-positive with a benign clinical outcome and relatively high complication of non-alcoholic fatty liver disease (NAFLD) were also identified. Only anti-gp210 was considered as a significant predictor for poor outcomes especially in patients with cirrhosis. Conclusion: Clustering methods allow the identification of distinct autoantibody profiles of PBC that form clinical subsets and can be useful for personalized approaches to diagnosis, clinical management, and the prediction of clinical outcomes. Anti-gp210 was the strongest predictive factor for poor outcomes especially in PBC patients with cirrhosis under real-world conditions.


Asunto(s)
Autoanticuerpos , Cirrosis Hepática Biliar , Humanos , Masculino , Femenino , Autoanticuerpos/análisis , Estudios Retrospectivos , Cirrosis Hepática Biliar/diagnóstico , Pacientes Internos , Anticuerpos Antinucleares/análisis , Cirrosis Hepática , China/epidemiología
3.
Huan Jing Ke Xue ; 41(9): 4141-4149, 2020 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-33124296

RESUMEN

Municipal wastewater methanogenesis is one of the ways to utilize municipal wastewater resources.In this study, a biofilter used to treat actual municipal wastewater was employed to investigate the methanogenesis in a pilot-scale reactor. The method of rapid start-up, the influence of temperature on the reactor performance, and the changes in the microbial structure were investigated in the pilot-scale study. The rapid start-up of the biofilter reactor was achieved by the combination of intermittent and continuous operations. The effluent concentration of SCOD was 60 mg ·L-1at the stable operation stage. The biofilter was operated steadily at a temperature higher than 14℃, the accumulation of volatile fatty acids (VFA) was low, and the effluent concentrations of SCOD and TCOD were 69 mg ·L-1and 90 mg ·L-1, respectively. In addition, the metabolism of hydrolysis and methanogenesis tended to balance off under such conditions. However, the abundance of microorganisms that can hydrolyze organic matter and produce methane decreased. The abundance of Peptostreptococcaceae increased even the temperature was lower than 10℃, which typically increases VFA production. Therefore, the concentrations of effluent VFA and TCOD increased, but methane production decreased. The effluent concentration of SCOD was relatively stable. The microbial abundance and diversity were the richest at 19℃ in the reactor. The acetolactic methanogens were the dominant methanogens at low temperatures. The anaerobic biological filter for the treatment of urban sewage starts quickly and can resist the impact of continuous temperature reduction. Moreover, it does not need backwashing after running for nine months, and it is not easily clogged.Therefore,the functions of biological contact oxidation and filtration retention of the biological filter can be more fully utilized.


Asunto(s)
Microbiota , Aguas Residuales , Anaerobiosis , Reactores Biológicos , Metano , Aguas del Alcantarillado , Temperatura , Eliminación de Residuos Líquidos
4.
Huan Jing Ke Xue ; 40(9): 4121-4127, 2019 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-31854876

RESUMEN

Upflow anaerobic filter (UAF) with actual domestic wastewater were examined in this study. The Impacts of hydraulic retention time (HRT) on the performance of a UAF and a primary methanogen group were investigated at mesophilic conditions. The chemical oxygen demand (COD) removal rate was more than 75% after 28 days acclimation at 35℃ and HRT of 24 h. With a gradual decrease in the HRT, the COD removal rate first increased and then decreased. When the HRT was 5 h, the COD removal rate was the highest, with an average 81.71% and a maximum of 87.18%. When the HRT decreased to 2.5 h, the average COD removal rate decreased to 75.12%. The methane produced per unit mass of substrate consumed (CH4/CODre) and volume fraction increased with a decrease in HRT. When the HRT was 2.5 h, it reached 0.30 L·g-1, and the volume fraction of methane was maintained at about 73%. The energy generated by the system met the energy demands of the peristaltic pump. Quantitative analysis of the primary methanogen group in the system indicates that Methanosarcinales is the dominant in the system. With a decrease in HRT, the abundances of acetoclastic and hydrogenotrophic methanogens increased significantly.

5.
Zhen Ci Yan Jiu ; 43(8): 492-4, 2018 Aug 25.
Artículo en Chino | MEDLINE | ID: mdl-30232851

RESUMEN

OBJECTIVE: To observe the influence of repeated shallow fire-needle acupuncture stimulation plus cupping on local neuralgia and serum substance P(SP)content in patients with acute herpes zoster (AHZ). METHODS: A total of 60 cases of AHZ patients were randomly divided into control (medication) group and treatment (medication plus fire-needle) group (n=30 in each). Patients of both groups were ordered to take Famciclovir (0.25 g/time, three times a day) and Mecobalamin (0.5 g/time, three times a day) orally for 7 days. In addition, patients of the treatment group were also treated by repeated shallow fire-needle stimulation and cupping, once a day for 7 days. Before and after the treatment, the patient's pain severity was assessed using visual analogue scale (VAS) and serum SP concentration was measured using ELISA. RESULTS: After the treatment, the VAS scores and serum SP concentrations in both groups were significantly decreased in comparison with those of their own pre-treatment (P<0.01), and were significantly lower in the treatment group than in the control group(P<0.01). There was a highly positive correlation between the decreased VAS score and serum SP content in the treatment group(P<0.01). CONCLUSION: Repeated shallow fire-needle stimulation plus cupping can accelerate the relief of local neuralgia in AHZ patients, which may be associated with its effect in down-regulating serum SP level.


Asunto(s)
Terapia por Acupuntura , Herpes Zóster , Moxibustión , Neuralgia , Humanos , Sustancia P , Resultado del Tratamiento
6.
Huan Jing Ke Xue ; 39(11): 5051-5057, 2018 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-30628228

RESUMEN

Batch experiments were conducted under normal temperature conditions to study the generation of N2O in the partial nitrification process under different dissolved oxygen concentrations and their production pathways. When dissolved oxygen was 0.5, 1.5, and 2.5 mg·L-1, the proportion of N2O released into the total nitrogen input was 4.35%, 3.27%, and 2.63%, respectively. With increase dissolved oxygen, the proportion of N2O released to total influent nitrogen was reduced. Isotope measurements showed that when dissolved oxygen was 0.5 mg·L-1, only denitrification by ammonia-oxidizing bacteria (AOB) produced N2O. However, when dissolved oxygen increased to 1.5 mg·L-1, the activity of nitrifying bacteria increased, and 4.52% of N2O was generated through a hydroxylamine oxidation process, whereas the N2O generated by AOB denitrification accounted for 95.48%. When dissolved oxygen continuously increased to 2.5 mg·L-1, the proportion of N2O produced by hydroxylamine oxidation increased to 9.11%, and the N2O generated by AOB denitrification accounted for 90.89%. The change in dissolved oxygen concentration affects the N2O production pathway in the short-cut nitrification process, and avoiding excessive NO2--N accumulation can reduce the production of N2O.


Asunto(s)
Bacterias/metabolismo , Desnitrificación , Nitrificación , Óxido Nitroso/análisis , Oxígeno/química , Amoníaco/química , Reactores Biológicos , Isótopos , Oxidación-Reducción , Aguas del Alcantarillado
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(11): 3671-5, 2016 Nov.
Artículo en Chino | MEDLINE | ID: mdl-30226685

RESUMEN

LIBS (laser-induced breakdown spectroscopy) was used to detect Fe element content in soybean oil quantitatively. In this experiment, a series of soybean oil samples with different concentrations of Fe were used; LIBS spectra were collected with a two-channel high precision spectrometer. According to the LIBS spectrum of samples, two characteristic wavelength of Fe (404.58 and 406.36 nm) were determined, and different simple regression methods (exponential regression, linear regression and quadratic regression) were used to establish the quantitative analysis models of Fe content using each characteristic spectral line. The results indicate that the average relative error of Fe I 404.58 and Fe I 406.36 in simple exponential regression, linear regression and quadratic regression models were 29.49%, 8.93%, 8.70% and 28.95%, 8.63%, 8.44%, respectively. The results of Fe I 406.36 regression models is better than that of Fe I 404.58, and the quadratic regression model is optimal among the three regression models. According to these results, LIBS technology has certain feasibility for detecting Fe in soybean oil; the quadratic linear regression model can improve the prediction accuracy of Fe element effectively.


Asunto(s)
Hierro/análisis , Rayos Láser , Análisis de Regresión , Aceite de Soja , Análisis Espectral
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(10): 3341-5, 2016 Oct.
Artículo en Chino | MEDLINE | ID: mdl-30246985

RESUMEN

In order to monitor chromium (Cr) content in soybean oil, laser induced breakdown spectroscopy (LIBS) was used to detect Cr content in this research. Pine wood chips was used to enrich heavy metal of Cr, and the spectra of pine wood chips were acquired in the wavelength range of 206.28~481.77 nm by a two-channel high-precision spectrometer. Then, uninformative variable elimination (UVE) method was used to select sensitive wavelength variables for heavy metal of Cr, and calibration model of Cr in soybean oil was developed with partial least squares (PLS) regression, the performance of the calibration model was compared to univariate and full PLS calibration models. The results indicate that the performance of UVE-PLS calibration model is better than that of univariate and full PLS calibration models, the correlation coefficient, root mean square error of calibration (RMSEC), root mean square error of cross validation (RMSECV), root mean square error of prediction (RMSEP) are 0.990, 0.045 mg·g-1, 0.050 mg·g-1 and 0.054 mg·g-1, respectively. After UVE variable selection, the number of wavelength variables in UVE-PLS calibration model is about 2% of wavelength variables in full PLS calibration model. This means UVE is an effective variable selection method which can select correlative variables for heavy metal of Cr.

10.
Appl Opt ; 51(23): 5657-63, 2012 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-22885578

RESUMEN

We report the lattice damage and annealing properties of the 500 keV Si+ ions implanted Nd:YVO4 crystal with different doses. The Rutherford backscattering spectrometry/channeling technique was used to analyze the damage profiles of ion-implanted samples. A series of post-implant annealing was performed at temperatures from 250 °C to 400 °C to investigate the relation between lattice damage profile and the waveguide formation. Implantations at doses of more than 5×10(14) ions/cm2 can result in high damage ratio in the near-surface region and the lattice structure cannot be restored even after annealing at 400 °C. Such seriously damaged lattice is relatively stable and contributes to the waveguide structure. Convergence of the refractive index at the surface region after ion implantation is believed mainly due to the elastic collisions with the target atoms caused by nuclear energy loss.

11.
Opt Express ; 20(6): 6712-9, 2012 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-22418555

RESUMEN

We report on the formation and the optical properties of the planar and ridge optical waveguides in rutile TiO2 crystal by He+ ion implantation combined with micro-fabrication technologies. Planar optical waveguides in TiO2 are fabricated by high-energy (2.8 MeV) He+-ion implantation with a dose of 3 × 10¹6 ions/cm² and triple low energies (450, 500, 550) keV He+-ion implantation with all fluences of 2 × 10¹6 ions/cm² at room temperature. The guided modes were measured by a modal 2010 prism coupler at wavelength of 1539 nm. There are damage profiles in ion-implanted waveguides by Rutherford backscattering (RBS)/channeling measurements. The refractive-index profile of the 2.8 MeV He+-implanted waveguide was analyzed based on RCM (Reflected Calculation Method). Also ridge waveguides were fabricated by femtosecond laser ablation on 2.8 MeV ion implanted planar waveguide and Ar ion beam etching on the basis of triple keV ion implanted planar waveguide, separately. The loss of the ridge waveguide was estimated. The measured near-field intensity distributions of the planar and ridge modes are all shown.


Asunto(s)
Iones Pesados , Refractometría/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Titanio/química , Titanio/efectos de la radiación , Diseño de Equipo , Análisis de Falla de Equipo , Helio , Iones
12.
Appl Opt ; 50(21): 3865-70, 2011 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-21772368

RESUMEN

We fabricated a single-mode planar waveguide in z-cut Nd:YVO(4) by multienergy He ion implantation in total fluence of 4.5×10(16) ions/cm(2) at room temperature and investigated optical properties of Nd:YVO(4) before and after He ion implantation by measuring transmission, confocal microluminescence, and confocal Raman spectra. Absorption bands and the photoluminescence features of the bulk Nd:YVO(4) crystal have been preserved after He ion implantation. In Raman spectra, most of the peak positions and peak widths had no obvious change before and after He ion implantation. The guiding mode and near-field image in the waveguide were measured by the prism coupling method and end-face coupling method, respectively. We investigated the damage behavior of a Nd:YVO(4) waveguide after implantation, annealing treatment by the Rutherford backscattering/channeling technique. The minimum yield of the virgin z-cut Nd:YVO(4) was 1.98%, which increased to 4.73% after He ion implantation and decreased to 3.20% after annealing at 600 K for 30 minutes.

14.
J Mater Sci Mater Med ; 21(10): 2817-25, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20857324

RESUMEN

Amphiphilic triblock copolymers monomethoxyl poly(ethylene glycol) (mPEG)-b-poly(ε-caprolactone) (PCL)-b-poly(aminoethyl methacrylate)s (PAMAs) (mPECAs) were synthesized as gene delivery vectors. They exhibited lower cytotoxicity and higher transfection efficiency in COS-7 cells in presence of serum compared to 25 kDa bPEI. The influence of mPEG and PCL segments in mPECAs was evaluated by comparing with corresponding diblock copolymers. The studies showed the incorporation of the hydrophobic PCL segment in triblock copolymers affected the binding capability to pDNA and surface charges of complexes due to the formation of micelles increasing the local charges. The presence of mPEG segment in gene vector decreased the surface charges of the complexes and increased the stability of the complexes in serum because of the steric hindrance effect. It was also found that the combination of PEG and PCL segments into one macromolecule might lead to synergistic effect for better transfection efficiency in serum.


Asunto(s)
Técnicas de Transferencia de Gen , Vectores Genéticos , Polímeros/química , Polímeros/síntesis química , Animales , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Materiales Biocompatibles/toxicidad , Células COS , Chlorocebus aethiops , Portadores de Fármacos/síntesis química , Portadores de Fármacos/química , Portadores de Fármacos/toxicidad , Etilaminas/química , Glicoles de Etileno/química , Espectroscopía de Resonancia Magnética , Ensayo de Materiales , Metacrilatos/química , Micelas , Tamaño de la Partícula , Poliésteres/química , Polietilenglicoles/química , Polímeros/toxicidad , Transfección
15.
Opt Express ; 18(15): 15609-17, 2010 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-20720942

RESUMEN

We report on the fabrication of planar and ridge waveguides in lithium niobate by proton exchange combined with oxygen ion implantation. The implanted energy ranges from 600 to 1400 keV with a dose of 1 x 10(15) ions/cm(2). The modes in proton exchanged waveguide can be modulated by O ion implantation. There are different damage profiles in proton-exchanged and ion-implanted waveguides in Rutherford backscattering/channeling spectra. The refractive index profile in single-mode waveguide in lithium niobate has been obtained based on Intensity Calculation Method. Also ridge waveguide was fabricated on the basis of planar waveguide by Ar ion beam etching. The measured near-field intensity distributions of the ridge waveguide modes show a reasonable agreement with the simulated ones. The estimated propagation loss was approximately 2.2 dB/cm.

16.
Huan Jing Ke Xue ; 30(4): 1084-9, 2009 Apr 15.
Artículo en Chino | MEDLINE | ID: mdl-19545010

RESUMEN

To achieve stable advanced nitrogen removal via nitrite in SBR, factors influencing pH variation in treating real domestic wastewater were investigated. The characteristic points were found to be appeared obviously on pH profile at both ends of ammonia oxidization and denitrification by analyzing the mechanism of biological nitrogen removal and the balance of carbonic acid. Using pH as control parameter in SBR for treating domestic or municipal wastewater with low organic concentration and suitable alkalinity could achieve advanced nitrogen removal with effluent TN below 1 mg/L. Moreover, it could prevent the decrease of nitrite accumulation rate causing by excessive aeration, which plays an important role on the stability of advanced nitrogen removal via nitrite. Based on theoretical analysis and experimental study, the real-time control strategy of advanced nitrogen removal via nitrite was established. To accommodate the different water quality and retain the accuracy of control strategy, 18 adjustable variables were set up in control strategy. The control strategy established a foundation for developing control software and control system of advanced nitrogen removal via nitrite.


Asunto(s)
Reactores Biológicos , Nitritos/aislamiento & purificación , Nitrógeno/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos , Biodegradación Ambiental , Reactores Biológicos/microbiología , Nitritos/química , Nitrógeno/química
17.
J Zhejiang Univ Sci B ; 9(12): 990-5, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19067468

RESUMEN

The effect of L-proline as a promoter on the condensation reaction of salicylaldehyde or its derivatives with ethyl acetoacetate in neutral ionic liquid [emim]BF4 was studied. All reactions were carried out under mild reaction conditions and achieved high yields. Moreover, the ionic liquid containing L-proline could be recycled and reused for several times without noticeably decreasing in productivity. The results show that the L-proline-[emim]BF4 system has a potential in contribution to the development of environmentally friendly and inexpensive processes in organic syntheses.


Asunto(s)
Cumarinas/síntesis química , Líquidos Iónicos/química , Prolina/química
18.
Huan Jing Ke Xue ; 29(7): 1874-9, 2008 Jul.
Artículo en Chino | MEDLINE | ID: mdl-18828369

RESUMEN

Nitrite has been found in previous research an inhibitor on anoxic phosphorus uptake in enhanced biological phosphorus removal systems (EBPR). However, the inhibiting nitrite concentration reported varied in a large range and no kinetics study concerned on anoxic phosphorus uptake. This study investigates the nitrite inhibition on anoxic phosphorus uptake with sequencing batch reactor (SBR) in different concentrations of NO2- and under different pH gradient. The activated sludge was cultured with A2/O Oxidation Ditch pilot-scale reactor performing EBPR. The progress of SBR is as follows: the activated sludge was taken out an aerobic zone of the A2/O Oxidation Ditch to SBR, then phosphorus was released with acetate fed in anaerobic phase, subsequently phosphorus uptake proceeded with NO2- added in anoxic phase. It is pointed that not only NO2- but pH inhibited anoxic phosphorus uptake. The result indicated that (1) specific denitrification rate and specific phosphorus uptake rate correlated the original nitrite accord with Andrews's inhibition model under the constant pH. (2) If pH was in the range of 6.5 to 8.0, nitrite inhibited DPR much stronger when pH was less, vice versa. (3) Kinetics parameter was as follows: the max specific denitrification rate was 4.55 mg/(g x h), the half saturation constant of the denitrification process was 2.14 mg/L; and the max specific phosphorus uptake rate was 3.06 mg/(g x h), the half saturation constant of the phosphorus uptake process was 2.64 mg/L.


Asunto(s)
Bacterias Anaerobias/metabolismo , Reactores Biológicos/microbiología , Nitritos/química , Dióxido de Nitrógeno/química , Fósforo/metabolismo , Biodegradación Ambiental , Electrones , Cinética , Fósforo/aislamiento & purificación , Eliminación de Residuos Líquidos/métodos
19.
Huan Jing Ke Xue ; 29(3): 660-4, 2008 Mar.
Artículo en Chino | MEDLINE | ID: mdl-18649524

RESUMEN

In order to reduce nitrous oxide (N2O) production from real wastewater and optimize the DO concentration and the aeration mode, nitrification efficiency and N2O production from nitrification treating domestic wastewater under difference DO concentrations were investigated using lab-scale SBR. The obtained results show energy consumption was saved at DO concentration of 0.4 mg L(-1), whereas, ammonia oxidation rate was very low. Ammonia oxidation rate was increased with DO increasing. N2O was produced during the nitrification for treating domestic wastewater with low ammonium concentration. N2O production at the DO concentration of 0.4 mg L(-1) and 0.9 mg L(-1) were 1.5 mg L(-1) and 1.6 mg L(-1), respectively. While N2O production at the DO concentration of 1.5 mg L(-1) and 2.0 mg L(-1) were 0.5 mg L 1)and 0.4 mg L-'(-1)respectively. When DO concentration increased above 1.5 mg L-'(-1)the ammonia oxidation rate increased slightly with N2 0O production sharply decreasing. Therefore, from the aspects of enhancing the efficiency of nitrogen removal with lower energy consumption and reducing N2 Oproduction, the optimal controlled DO concentration was 1.5 mg L-. -1)


Asunto(s)
Reactores Biológicos , Nitrógeno/química , Óxido Nitroso/química , Oxígeno/química , Eliminación de Residuos Líquidos/métodos , Nitrógeno/metabolismo , Óxido Nitroso/metabolismo , Oxidación-Reducción , Oxígeno/metabolismo
20.
Int J Syst Evol Microbiol ; 58(Pt 6): 1458-62, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18523194

RESUMEN

The taxonomic position of a novel Gram-negative strain, designated SY1(T), isolated from a farm-soil sample obtained from Jiangsu Province, PR China, was characterized by using a polyphasic approach. The cells were non-motile, non-spore-forming rods. The organism grew optimally at 30-37 degrees C and at pH 6.0-8.0. Based on 16S rRNA gene sequence analysis, strain SY1(T) is a member of the genus Sphingobacterium; Sphingobacterium multivorum JCM 21156(T) was the nearest relative (98.5 % sequence similarity). The predominant fatty acids of strain SY1(T) were iso-C(15 : 0) (32.9 %), C(16 : 0) (10.9 %) and summed feature 3 (iso-C(15 : 0) 2-OH and/or C(16 : 1)omega7c; 24.1 %). The DNA G+C content was 38.5 mol%. The low level of DNA-DNA relatedness (2.2 %) to S. multivorum JCM 21156(T) in combination with differential morphological and biochemical properties demonstrated that strain SY1(T) (=KCTC 22131(T)=CGMCC 1.6855(T)) should be classified as representing a novel species of the genus Sphingobacterium for which the name Sphingobacterium siyangense sp. nov. is proposed.


Asunto(s)
Agricultura , Microbiología del Suelo , Sphingobacterium/clasificación , Sphingobacterium/aislamiento & purificación , Técnicas de Tipificación Bacteriana , China , ADN Bacteriano/análisis , ADN Ribosómico/análisis , Ácidos Grasos/análisis , Genes de ARNr , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Fenotipo , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Especificidad de la Especie , Sphingobacterium/genética , Sphingobacterium/fisiología
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