RESUMO
Biologically active ß-1,3-oligosaccharides with rapidly growing biomedical applications are produced from hydrolysis of curdlan polysaccharide. The water-insoluble curdlan impedes its hydrolysis efficiency which is enhanced by our newly developed alkali-neutralization treatment process to increase the stability of curdlan suspension to more than 20 days, while the untreated control settled within 5 min. A putative double-layer structure model comprising of a compact core and a hydrated outer layer was proposed to describe the treated curdlan particles based on sedimentation and scanning electron microscopy observation. This model was verified by single- and two-step acid hydrolysis, indicative of the reduced susceptibility to hydrolysis when close to the compact core. Electrospray ionization-mass spectrometry, thin-layer chromatography analyses, and effective HPLC procedure led to the development of improved process to produce purified individual ß-1,3-oligosaccharides with degrees of polymerization from 2 to 10 and potential for biomedical applications from curdlan hydrolyzate. Our new curdlan oligosaccharide production process offers an even better alternative to the previously published processes.
Assuntos
Ácidos/química , Álcalis/química , Oligossacarídeos/isolamento & purificação , beta-Glucanas/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Hidrólise , Microscopia Eletrônica de Varredura , Espectrometria de Massas por Ionização por Electrospray , ÁguaRESUMO
OBJECTIVE: To establish a stable mouse model of acquired aplastic anemia. METHODS: Female BALB/C mice aged 6 months were intraperitoneally injected with cyclophosphamide and cyclosporine for 14 days. The number of peripheral blood cells, the concentration of hemoglobin, the number of bone marrow nucleated cells, bone marrow smear, bone marrow pathological sections and other indexes were observed. RESULTS: In BALB/C mice injected intraperitoneally with cyclophosphamide and cyclosporine, the number of peripheral blood cells and the concentration of hemoglobin were significantly decreased, especially the white blood cells and platelets. Bone marrow smear showed a significant decrease in the number of nucleated cells and bone marrow hyperplasia. Bone marrow pathology showed decreased hematopoietic cells and increased non-hematopoietic cells such as adipocytes. CONCLUSION: The mouse model with intraperitoneal injection of cyclophosphamide and cyclosporine can meet the diagnostic criteria of acquired aplastic anemia, which can be used as a mouse model for the study of the pathogenesis and treatment of acquired aplastic anemia.
Assuntos
Anemia Aplástica , Animais , Medula Óssea , Ciclofosfamida , Ciclosporina , Feminino , Camundongos , Camundongos Endogâmicos BALB CRESUMO
The objective of this study was to evaluate the effects and underlying physiological mecha-nisms of partial root zone irrigation (PRI) and rational close planting, as well as their interaction on yield and water productivity (WP) of cotton and to explore new alternatives of water-saving irrigation in dry land areas. A factorial field experiment with irrigation mode (normal irrigation, partial root-zone irrigation and deficient irrigation) and plant population density (135000, 180000 and 225000 plants·hm-2) was conducted in the west of Inner Mongolia to examine their effects on cotton growth, yield, water productivity and related physiological characters. The results showed that the irrigation mode and plant density as well as their interaction significantly affected the biomass, yield, yield components and harvest index. Under normal irrigation, the biomass and the number of bolls per unit area increased with the increasing of plant density, but the harvest index and boll weight significantly reduced. The yield of high plant density was comparable to that of medium plant density, both of which were increased significantly compared with that of low plant density. The content of abscisic acid (ABA) significantly increased and that of auxin (IAA) significantly reduced in cotton leaves under partial root-zone irrigation, which significantly increased the harvest index by improving the partitioning of assimilates to reproductive organs under partial root-zone irrigation. The number of bolls per unit area increased and boll mass remained unchanged with the increasing of density under partial root-zone irrigation. The yield of high density increased by 6.7% and 11.5% compared with that of medium and low density under partial root zone irrigation. The pre-frost seed cotton increased by 22.5%, the amount of irrigation reduced by 30%, and water productivity increased by 49.3% under partial root zone irrigation compared with that under normal irrigation at high plant density. Plant density did not affect photosynthetic rate (Pn) of functional leaves, but irrigation mode significantly affected Pn. Deficient irrigation significantly reduced the Pn of the main-stem functional leaves, but the Pn under partial root-zone irrigation was comparable to that of normal irrigation. The jasmonate (JA) content and the expression level of plasma membrane intrinsic protein (PIP) gene were significantly increased in the hydrated root under partial root-zone irrigation compared with those under normal irrigation. The results suggested that the increased JA content, as a signal molecule, up-regulated the expression level of PIP gene in dehydrated root and increased water uptake capacity of roots and guaranteed water balance of leaves, and then contributed to a relatively high Pn. Partial root-zone irrigation combined with relatively high plant density (225000 plants·hm-2) is an important agronomic alternative for water saving in cotton plantation in the dry land areas.
Assuntos
Irrigação Agrícola/métodos , Gossypium/crescimento & desenvolvimento , Água , Biomassa , China , FotossínteseRESUMO
Proline is a special imino acid in protein and the isomerization of the prolyl peptide bond has notable biological significance and influences the final structure of protein greatly, so the correlation between proline synonymous codon usage and local amino acid, the correlation between proline synonymous codon usage and the isomerization of the prolyl peptide bond were both investigated in the Escherichia coli genome by using a novel method based on information theory. The results show that in peptide chain, the residue at the first position C-terminal influences the usage of proline synonymous codon greatly and proline synonymous codons contain some factors influencing the isomerization of the prolyl peptide bond.
Assuntos
Códon/genética , Escherichia coli/genética , Prolina/genética , Genoma Bacteriano , Peptídeos/química , Conformação ProteicaRESUMO
In this paper a software sensor based on a fuzzy neural network approach was proposed for real-time estimation of nutrient concentrations. In order to improve the network performance, fuzzy subtractive clustering was used to identify model architecture, extract and optimize fuzzy rule of the model. A split network structure was applied separately for anaerobic and aerobic conditions was employed with dynamic modeling methods such as autoregressive with exogenous inputs and multi-way principal component analysis (MPCA). The proposed methodology was applied to a bench-scale anoxic/oxic process for biological nitrogen removal. The simulative results indicate that the learning ability and generalization of the model performed well and also worked well for normal batch operations corresponding to three data points inside the confidence limit determined by MPCA. Real-time estimation of NO(3)(-), NH(4)(+) and PO(4)(3-) concentration based on fuzzy neural network analysis were successfully carried out with the simple on-line information regarding the anoxic/oxic system.
Assuntos
Reatores Biológicos , Oxigênio/química , Algoritmos , Amônia/química , Meios de Cultura/metabolismo , Desenho de Equipamento , Lógica Fuzzy , Modelos Estatísticos , Redes Neurais de Computação , Nitrogênio/química , Fosfatos/química , Análise de Componente Principal , Análise de Regressão , Software , Fatores de TempoRESUMO
Based on the acquisition of heavy metal data from 216 topsoil samples of the agricultural land in Baoshan District, a typical region of Shanghai City, the content, distribution characteristics and sources of the heavy metals in agricultural soil of Shanghai Baoshan District were analyzed with the methods of combining multivariate statistics and geo-statistical. The results show that the average concentrations of the Cd, Hg, As, Cr, Pb, Cu and Zn in agricultural soil of Baoshan District are 0.195, 0.148, 7.44, 82.5, 29.1, 33.2 and 124.5 mg x kg(-1), they are lower than the secondary standards of the national soil environment; but the average concentrations of the Cd, Hg, Cr, Pb, Cu and Zn are more than background values of soil in Shanghai. Especially the Cd, Hg, Zn, they are 1.50, 1.48, 1.45 times higher than the background values, showing a net cumulative trend. The results of correlation analysis and factor analysis show that the sources of these elements can be divided into three categories; the Zn, Cd, Hg and Pb as one class; the Cr and Cu as another class; the As in a separate category. The concentrations of the former two classes are much higher than the background value, implying mainly from various human activities; the content of the As is almost the same as the background value of soil, it has the lowest degree of variation. Spatial structure analysis shows that the distribution of the As is influenced by the soil structural variations, such as soil parent material, topography, and other elements are mainly affected by random factors of human activities. Through the probability distribution of contour lines of the critical value, it can be found that the Cd, Zn, Cr, Cu, Hg come mainly from the point sources of pollution, but the source of Pb is relatively dispersed.
Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Agricultura , China , Cidades , Análise Multivariada , Solo/análiseRESUMO
OBJECTIVE: To verify the improvement function of warming-reinforcing acupuncture combined with rehabilitation training on the early motor function of hemiparalysis patients caused by ischemic brain stroke. METHODS: Eighty cases were randomly divided into a warming-reinforcing acupuncture combined with rehabilitation training group (group A) and a rehabilitation training group (group B), 40 cases in each group. Both groups were treated with internal routine treatment. The Motor Relearning Program rehabilitation was used in group B, while warming-reinforcing acupuncture combined with Motor Relearning Program rehabilitation were used in group A. Jianyu (LI 15), Quchi (LI 11), Hegu (LI 4), Yanglingquan (GB 34), Yinlingquan (SP 9), Zusanli (ST 36), Sanyinjiao (SP 6) were selected, and warming-reinforcing method was used in these points, they were treated for 3 weeks. The neurological functional deficits scores of hemiparalysis patients, Fugl-Meyer Score, Motor Function Assessment Score (MAS), Barthel Index and Mini-mental State Examination (MMSE) were used to evaluate the condition of hemiparalysis patients before and after treatment. RESULTS: The effective rate of group A (87.5%, 35/40) superior to that of group B (67.5%, 27/40) (P < 0.05). The neurological functional deficit scores, Fugl-Meyer score, MAS and Barthel Index of both groups were improved after treatment (P < 0.01, P < 0.05), and the improved degree of group A was better than that of group B (P < 0.01, P < 0.05). CONCLUSION: There is obvious improvement function of warming-reinforcing acupuncture combined with rehabilitation training on the early motor function of hemiparalysis patients caused by ischemic brain stroke, and the function is better than that of simple rehabilitation training.
Assuntos
Terapia por Acupuntura , Isquemia Encefálica/complicações , Hemiplegia/reabilitação , Hemiplegia/terapia , Atividade Motora , Acidente Vascular Cerebral/complicações , Atividades Cotidianas , Adulto , Idoso , Idoso de 80 Anos ou mais , Hemiplegia/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
OBJECTIVE: To observe the therapeutic effect of heat-reinforcing needling combined with modem rehabilitation training on the motor function of ischemic stroke patients. METHODS: Fifty case of ischemic stroke patients were randomly divided into rehabilitation (Rehab, n=40) and acupuncture (Acup) + Rehab (n=40) groups. Heat-reinforcing needling was applied to Jianyu (LI 15), Quchi (LI 11), Hegu (LI 14), Zusanli (ST 36), Yanglingquan (GB 34), Yinlingquan (SP 9) and Sanyinjiao (SP 6), once daily for 3 weeks. Rehabilitation training including healthy limb and joint movement was conducted, once daily for 3 weeks. The patient's neurological impairment degree and the motor function (Fugl-Meyer index) were evaluated before and after the treatment. RESULTS: After the treatment, of the each 40 cases in Rehab and Acup + Rehab groups, 10 (25.0%) and 17 (42.5%) experienced marked improvement in their symptoms, 17 (42.5%) and 18 (45.0%) had improvement, 13 (32.5%) and 5 (12.5%) failed, with the effective rates being 67.5% and 87.5% respectively. The therapeutic effect of Acup + Rehab group was markedly superior to that of Rehab group (P<0.05). Comparison between two groups showed no significant differences in the scores of clinical neurological impairment degree and the scores of Fugl-Meyer index before the treatment (P>0.05). After the treatment, the scores of neurological impairment degree of two groups both decreased significantly (P<0.05), and the scores of the Fugl-Meyer index of the upper and lower limbs increased significantly in two groups (P<0.05). The score of neurological impairment degree of Acup + Rehab group was significantly lower than that of Rehab group (P<0.05), while the scores of the Fugl-Meyer index of two limbs of Acup + Rehab group were obviously higher than those of Rehab group (P<0.01). CONCLUSION: The therapy of heat-reinforcing needling combined with rehabilitation training is significantly superior to that of simple rehabilitation training in improving neurological impairment and motor function of ischemic stroke patients.
Assuntos
Terapia por Acupuntura , Isquemia Encefálica/reabilitação , Isquemia Encefálica/terapia , Atividade Motora , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/fisiopatologiaRESUMO
With the removal of vegetative branches plus the maintenance of early fruiting branches as the control, the effects of various training modes on the source-sink relation of field-grown cotton were examined in 2005 and 2006. The results showed that compared with the control, either the removal of vegetative branches plus the removal of early fruiting branches (I), the maintenance of vegetative branches plus the removal of early fruiting branches (II), or the maintenance of vegetative branches plus the maintenance of early fruiting branches (III) could increase the leaf area per plant significantly, with the average maximum LAI across the two years increased by 10.3%, 28.3%, and 9.5%, respectively, and resulting in the decreases of the load per leaf area and the ratio of sink to source. I and II alleviated the leaf senescence of cotton plants as indicated by the enhanced leaf chlorophyll content and the reduced percentage of yellow leaves and C/N ratio of functional leaves, and II also induced the late-maturing of cotton plants. III had no significant effects on senescence alleviation. I produced approximately equal seed cotton, but II and III produced 6.4%-15.6% less and 6.3% more seed cotton than the control, respectively. It was concluded that either the maintenance of vegetative branches or the removal of early fruiting branches could be an effective pathway to regulate the ratio of sink to source, C/N, and maturity performance of cotton plants.
Assuntos
Agricultura/métodos , Biomassa , Gossypium/crescimento & desenvolvimento , Carbono/metabolismo , Gossypium/metabolismo , Nitrogênio/metabolismoRESUMO
Alpha-amylase is an enzyme of great significance to industry, but most alpha-amylases are unstable at lower pH. In this paper, we have studied the related dipeptide and characteristic dipeptide of optimal pH in alpha-amylase. On analysis, it gives the explicit results as follows: (1) Ten dipeptides are associated with alpha-amylase's optimal pH. AH, DV, EH, HR, and YV are of positive correlation, AM, IC, NG, NL, and PS are of negative correlation. (2) GE, RE, GS, and KS are higher pH alpha-amylase characteristic dipeptides; AS, GS, DY, and GI are high pH alpha-amylase characteristic dipeptides; TE, VR, DS, and ET are middle pH alpha-amylase characteristic dipeptides; DK, NT, PT, and RV are low pH alpha-amylase characteristic dipeptides; AT, DS, GR, and SR are lower pH alpha-amylase characteristic dipeptides.
Assuntos
Dipeptídeos/metabolismo , alfa-Amilases/metabolismo , Dipeptídeos/química , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , alfa-Amilases/químicaRESUMO
In this paper, a novel approach has been introduced to predict the disulfide-bonding state of cysteines in proteins by means of a linear discriminator based on their dipeptide composition. The prediction is performed with a newly enlarged dataset with 8114 cysteine-containing segments extracted from 1856 non-homologous proteins of well-resolved three-dimensional structures. The oxidation of cysteines exhibits obvious cooperativity: almost all cysteines in disulfide-bond-containing proteins are in the oxidized form. This cooperativity can be well described by protein's dipeptide composition, based on which the prediction accuracy of the oxidation form of cysteines scores as high as 89.1% and 85.2%, when measured on cysteine and protein basis using the rigorous jack-knife procedure, respectively. The result demonstrates the applicability of this new relatively simple method and provides superior prediction performance compared with existing methods for the prediction of the oxidation states of cysteines in proteins.