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1.
J Ophthalmol ; 2021: 8853811, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33777447

RESUMO

Nanophthalmos is a clinical phenotype of simple microphthalmos, in which the anterior and posterior segments of the eyeball do not develop into a normal size without other major ocular or systemic anomalies. Typical clinical manifestations of nanophthalmos include short axial length, thickened sclera, small cornea, shallow anterior chamber, and increased lens-to-eye volume ratio. Currently, there is a lack of recognized diagnostic criteria for nanophthalmos. With the development of eye examination technologies, such as biological measurement and imaging examination, visualization and quantification of the eyeball's shape and structure in nanophthalmos can be realized. New clinical features have been reported, which are of great significance for diagnosing and treating nanophthalmos. This review introduces the related concepts of nanophthalmos and the new developments in its clinical characterization.

2.
Optom Vis Sci ; 97(12): 1099-1104, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33252540

RESUMO

SIGNIFICANCE: This review summarizes the main factors of refractive error after silicone oil removal combined with cataract surgery.The post-operative refractive results of silicone oil removal combined with cataract surgery are closely related to the patient's future vision quality. This report summarizes the factors that influence the difference between the actual post-operative refractive power and the pre-operatively predicted refractive power after silicone oil removal combined with cataract surgery, including axial length, anterior chamber depth, silicone oil, commonly used tools for measuring intraocular lens power, and intraocular lens power calculation formulas, among others. The aim of the report is to assist clinical and scientific research on the elimination of refractive error after silicone oil removal combined with cataract surgery.


Assuntos
Extração de Catarata/efeitos adversos , Erros de Refração/etiologia , Óleos de Silicone , Sucção/efeitos adversos , Câmara Anterior/patologia , Comprimento Axial do Olho/patologia , Tamponamento Interno , Humanos , Implante de Lente Intraocular , Erros de Refração/prevenção & controle , Testes Visuais
3.
Huan Jing Ke Xue ; 40(7): 3355-3360, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854738

RESUMO

The red soils in southern China are generally classified as phosphorus-deficient, and therefore planting crops in these regions usually requires high applications of phosphate fertilizer. However, the effect of phosphorus addition on N2O emissions in rice-rapeseed rotation soils is not clear. We carried out an incubation experiment with the rice-rapeseed rotation soil from Qianjiang and Xianning to explore the effect of different concentrations of phosphorus (0, 15, and 30 mg·kg-1) and different concentrations of nitrogen (0 and 100 mg·kg-1) on N2O emission. Studies have shown that the addition of phosphorus has a significant effect on soil N2O emissions, but the pathways of impact are varied:in the case of low nitrogen soil, the addition of phosphorus promotes the fixation of nitrogen in the soil by microorganisms and thus reduces N2O emissions; in case of sufficient nitrogen content in soil, adding less phosphorus promotes the activity of nitrifies and thereby promotes the emission of N2O, while adding more phosphorus also promotes fixation by microorganisms in the soil; when there is a high content of available phosphorus in the soil, whether the nitrogen is sufficient or not, the addition of phosphorus will inhibit the emission of N2O.

4.
Dis Markers ; 2018: 8721379, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29849828

RESUMO

Extracellular superoxide dismutase (ecSOD) is the major extracellular scavenger of reactive oxygen species and associated with the diabetic complication in patients with type 2 diabetes mellitus (T2DM). We aimed to investigate the serum ecSOD activity in Chinese patients with different stages of diabetic retinopathy (DR) and evaluate the association between the serum ecSOD activity and the severity of DR. A total of 343 T2DM patients were categorized into three groups: nondiabetic retinopathy (NDR) group, nonproliferative diabetic retinopathy (NPDR) group, and proliferative diabetic retinopathy (PDR) group. Serum ecSOD activities were measured by the autoxidation of the pyrogallol method. In this study, 271, 46, and 26 patients were enrolled in the NDR, NPDR, and PDR groups, respectively. We found a significantly decreased trend of serum ecSOD activity among NDR subjects (118.0 ± 11.5 U/mL) compared to NPDR subjects (108.5 ± 11.9 U/mL) (P < 0.001) and NPDR subjects compared to PDR subjects (102.7 ± 12.4 U/mL) (P = 0.041). Serum ecSOD activity was an independent risk factor for DR (OR = 0.920, P < 0.001) and was associated with the progression of DR. Serum ecSOD activity might be a biomarker for DR screening and evaluation of the clinical severity of DR in Chinese T2DM patients.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Retinopatia Diabética/sangue , Superóxido Dismutase/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Biomarcadores/metabolismo , Estudos de Casos e Controles , Retinopatia Diabética/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Superóxido Dismutase/metabolismo
5.
J Ophthalmol ; 2018: 7389412, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29850211

RESUMO

The surgical outcomes of macular holes (MHs) have improved greatly in recent years. The closure rate is as high as 90-100%, but the outcomes of some special types of MHs remain unsatisfactory. Internal limiting membrane (ILM) peeling dramatically improves the anatomic success rate, but recent studies have found that it could also cause mechanical and subclinical traumatic changes to the retina. Dyes are widely used, and apart from indocyanine green (ICG), the toxicities of other dyes require further research. Face-down posturing is necessary for MHs larger than 400 µm, and the duration of this posture is determined by the type of tamponade and the case. The ellipsoid zone has been shown to be highly correlated with visual outcome and recovery. New surgical methods include the inverted ILM flap technique and the ILM abrasion technique. However, they require further research to determine their effectiveness.

6.
Sci Rep ; 7(1): 15809, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-29150650

RESUMO

The freshwater snail Oncomelania hupensis is the unique intermediate host of the blood fluke Schistosoma japonicum, which is the major cause of schistosomiasis. The snail inhabits two contrasting environments: the hilly and marshland regions. The hilly snails are smaller in size and have the typical smooth shell, whereas the marshland snails are larger and possess the ribbed shell. To reveal the differences in gene expression between the hilly and marshland snails, a total of six snails, three per environment, were individually examined by RNA sequencing technology. All paired-end reads were assembled into contigs from which 34,760 unigenes were predicted. Based on single nucleotide polymorphisms, principal component analysis and neighbor-joining clustering revealed two distinct clusters of hilly and marshland snails. Analysis of expression changes between environments showed that upregulated genes relating to immunity and development were enriched in hilly snails, while those associated with reproduction were over-represented in marshland snails. Eight differentially expressed genes between the two types of snails were validated by qRT-PCR. Our study identified candidate genes that could be targets for future functional studies, and provided a link between expression profiling and ecological adaptation of the snail that may have implications for schistosomiasis control.


Assuntos
Ecossistema , Perfilação da Expressão Gênica , Schistosoma/fisiologia , Análise de Sequência de RNA , Caramujos/genética , Caramujos/parasitologia , Transcriptoma/genética , Animais , China , Análise por Conglomerados , Regulação da Expressão Gênica , Ontologia Genética , Geografia , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único/genética , Reprodutibilidade dos Testes
7.
Artigo em Chinês | MEDLINE | ID: mdl-27356422

RESUMO

Lysozyme generally exists in animals, plants and microorganisms, and it is used as a natural anti-infection material and one of the important non-specific immune factors in organisms. This paper reviews the progress of researches on its classification, gene structure and function, and expression regulation in Oncomelania hupensis, and on the factors affecting its activities in recent years, in order to further discuss its distribution in O. hupensis.


Assuntos
Muramidase/fisiologia , Caramujos/enzimologia , Animais , Expressão Gênica , Muramidase/classificação , Muramidase/genética
8.
Ying Yong Sheng Tai Xue Bao ; 25(5): 1340-8, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25129934

RESUMO

Dynamics of soil organic carbon mineralization affected by long-term fertilizations and temperature in relation to different soil carbon fractions were investigated in paddy soils. Soil samples were collected from the plough layer of 3 long-term national experimental sites in Xinhua, Ningxiang and Taojiang counties of Hunan Province. Mineralization of soil organic C was estimated by 33-day aerobic incubation at different temperatures of 10, 20 and 30 degrees C. The results showed that the rates of CO2 production were higher during the earlier phase (0-13 d) in all treatments, and then decreased according to a logarithm function. Higher incubation temperature strengthened C mineralization in the different treatments. The quantities of cumulative CO2 production in NPK with manure or straw treatments were greater than in inorganic fertilizers treatments. The Q10 values in the different soil treatments ranged from 1.01-1.53. There were significantly positive correlations between the Q10 values and soil total organic carbon (TOC), easy oxidation organic carbon (EOOC), humic acid carbon (C(HA)), fulvic acid carbon (CFA). The cumulative amount of mineralized C was significantly positively correlated with microbial biomass carbon (MBC) at 10 and 20 degrees C, but not significantly at 30 degrees C. Significant correlations were found between the cumulative amount of mineralized C and different soil carbon fractions and C(HA)/C(FA). The correlations of differ- ent soil carbon fractions with the ratio of cumulative mineralized C to TOC were negatively correlated at 10 degrees C, but not significantly at 20 and 30 degrees C. These results suggested that the application of NPK with manure or straw would be helpful to increase the sequestration of C in paddy soils and reduce its contribution of CO2 release in the atmosphere.


Assuntos
Carbono/análise , Fertilizantes , Solo/química , Temperatura , Biomassa , Substâncias Húmicas , Esterco , Oryza , Microbiologia do Solo
9.
Artigo em Chinês | MEDLINE | ID: mdl-25051822

RESUMO

OBJECTIVE: To explore the relationship between the Yangtze River floodplain ecological environment (vegetation, soil, water and light intensity) and the distribution of Oncomelania hupensis snails, so as to provide the evidence for ecological snail control. METHODS: Three regions (the Lu-Gang Bridge, Dragon Nest Lake in the bund, and Dragon Nest lake beach) were selected to investigate the plant characteristics (species, height, coverage, frequency and strain of clusters), soil characteristics (temperature, humidity, light intensity) and pH value. All the results were analyzed statistically with SPSS 18 software. RESULTS: A total of 920 boxes were investigated. The vegetation coverage was 3.7%-63.5%, and the dominant population was Cyperusrotundus L. cluster on the marshland. The soil temperature was 19.0 degrees C-24.0 degrees C, pH 5.0-5.7, and humidity 53%-75%. There were statistical significants in average number of living snails and dead snails among 3 groups (P < 0.05). As the light intensity was strong in summer and weak in winter, the snails were in the back surface in summer and front surface in winter respectively. The average number of living snails was the most near the water. The difference was statistical significant (P < 0.01) among three ranges (0-1 m, 1-3 m and 3-5 m). CONCLUSION: The snail survival and distribution have close relations with micro ecological environment factors, such as vegetation, soil, water and light intensity.


Assuntos
Inundações , Rios , Caramujos/crescimento & desenvolvimento , Animais , Vetores de Doenças , Controle de Pragas
10.
Artigo em Chinês | MEDLINE | ID: mdl-24822359

RESUMO

Oncomelania hupensis snails were collected from Qingyi River of Wuhu City from August 2012 to July 2013. Livers and pedal muscles of snails were dissected. Anthrone colorimetric method was used to evaluate the glycogen concentrations of whole-body, liver and muscle. The concentration of whole-body and liver glycogen decreased from September to next June. The whole body glycogen content in female (0.55 microg/mg) and male (0.88 microg/mg) snails was the lowest in June and April, respectively. The mean whole-body glycogen concentration in females and males was 2.99 and 3.39 microg/mg, respectively. Liver glycogen concentration was lowest in May (female = 0.29 microg/mg, male = 0.22 microg/mg), and reached peak level in August (female = 2.49 microg/mg, male = 2.78 microg/mg). The average liver glycogen concentration in female and male snails was 1.09 and 0.89 microg/mg, respectively. The muscle glycogen concentration gradually decreased from February to June, the lowest was found in June (female = 0.25 microg/mg, male = 0.41 microg/mg), and reached peak level in December (female =16.59 microg/mg, male = 10.06 microg/mg). The average muscle glycogen concentration in female and male snails was 799 and 605 microg/mg, respectively. There was a positive linear correlation between whole-body and liver glycogen concentrations (P < 0.05), and both of them had the similar trend in their monthly change. A positive linear correlation was found among whole-body, liver and muscle glycogen concentrations (P < 0.05).


Assuntos
Glicogênio/metabolismo , Caramujos/metabolismo , Animais , Fígado , Estações do Ano
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(9): 2478-82, 2013 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-24369656

RESUMO

The spectrometric oil analysis(SOA) is an important technique for machine state monitoring, fault diagnosis and prognosis, and SOA based remaining useful life(RUL) prediction has an advantage of finding out the optimal maintenance strategy for machine system. Because the complexity of machine system, its health state degradation process can't be simply characterized by linear model, while particle filtering(PF) possesses obvious advantages over traditional Kalman filtering for dealing nonlinear and non-Gaussian system, the PF approach was applied to state forecasting by SOA, and the RUL prediction technique based on SOA and PF algorithm is proposed. In the prediction model, according to the estimating result of system's posterior probability, its prior probability distribution is realized, and the multi-step ahead prediction model based on PF algorithm is established. Finally, the practical SOA data of some engine was analyzed and forecasted by the above method, and the forecasting result was compared with that of traditional Kalman filtering method. The result fully shows the superiority and effectivity of the

12.
Artigo em Chinês | MEDLINE | ID: mdl-24490395

RESUMO

OBJECTIVE: To explore the killing effects of exogenous NO on the cercariae of Schistosoma japonicum in vitro and the blocking effects of NO inhibitors. METHODS: The cercariae of S. japonicum were collected from naturally infected snails, and then formulated into a 1000 cercariae/ml suspension with RPMI 1640 medium. The relationship between the killing effects and doses of exogenous NO on cercariae were investigated through the suspension with different concentrations of NO generating agents (SNP) and negative control (without SNP). On the other hand, the blocking effects were also investigated through the suspensions being added 2.00 mmol/L SNP and four different NO inhibitors, Hb, FeSO4, L-cyst, L-arg and their combination. Additionally, the appropriate positive(2.00 mmol/L SNP) and negative controls (without NO generating agent) were used. RESULTS: The mortality rates of cercariae were (8.3 +/- 1.1)%, (6.26 +/- 2.3)%, and (9.3 +/- 1.0)% in the SNP 0.06, 0.1 and 0.2 mmol/L groups, respectively, and there were no statistically significant differences between the blank control group and the above-mentioned three groups, respectively (P > 0.05). The mortality rates of cercariae were(23.5 +/- 3.9)%, (46.0 +/- 1.1)%, and (59.4 +/- 0.5)% in the SNP 0.50, 1.00 and 2 mmol/L groups, respectively, and there were statistically significant differences between the blank control group and the above-mentioned groups, respectively (P < 0.05). The mortality rates of cercariae were (30.1 +/- 1.2)%, (45.1 +/- 1.4)%, (31.1 +/- 1.3)%, (34.2 +/- 3.1)%, (47.8 +/- 2.0)%, (49.1 +/- 0.6)%, and (44.2 +/- 0.1)% in the 2.00 mmol/L SNP suspensions which were added of Hb, FeSO4, L-cyst, L-arg, FeSO4+L-cyst, FeSO4+L-arg, FeSO4+L-arg+L-cyst, respectively. Compared with the 2.00 mmol/L SNP suspension, the mortality rates of the above-mentioned groups declined, and there were statistically significant differences (P < 0.05). CONCLUSION: There are killing effects of exogenous NO on the cercariae of S. japonicum in vitro, and four different NO inhibitors, Hb, FeSO4, L-cyst, L-arg and their combinations have some different degrees of blocking effects.


Assuntos
Cercárias/efeitos dos fármacos , Óxido Nítrico/farmacologia , Schistosoma japonicum/efeitos dos fármacos , Animais , Arginina/farmacologia , Cisteína/farmacologia , Compostos Ferrosos/farmacologia , Hemoglobinas/farmacologia , Nitroprussiato/farmacologia
13.
Chemistry ; 18(12): 3631-6, 2012 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-22328175

RESUMO

The induced aggregation of achiral building blocks by a chiral species to form chiral aggregates with memorized chirality has been observed for a number of systems. However, chiral memory in isolated aggregates of achiral building blocks remains rare. One possible reason for this discrepancy could be that not much is understood in terms of designing these chiral aggregates. Herein, we report a strategy for creating such isolable chiral aggregates from achiral building blocks that retain chiral memory after the facile physical removal of the chiral templates. This strategy was used for the isolation of chiral homoaggregates of neutral achiral π-conjugated carboxylic acids in pure aqueous solution. Under what we have termed an "interaction-substitution" mechanism, we generated chiral homoaggregates of a variety of π-conjugated carboxylic acids by using carboxymethyl cellulose (CMC) as a mediator in acidic aqueous solutions. These aggregates were subsequently isolated from the CMC templates whilst retaining their memorized supramolecular chirality. Circular dichroism (CD) spectra of the aggregates formed in the acidic CMC solution exhibited bisignated exciton-coupled signals of various signs and intensities that were maintained in the isolated pure homoaggregates of the achiral π-conjugated carboxylic acids. The memory of the supramolecular chirality in the isolated aggregates was ascribed to the substitution of COOH/COOH hydrogen-bonding interaction between the carboxylic acid groups within the aggregates for the hydrogen-bonding interactions between the COOH groups of the building blocks and the chiral templates. We expect that this "interaction-substitution" procedure will open up a new route to isolable pure chiral aggregates from achiral species.

14.
Org Biomol Chem ; 10(7): 1418-23, 2012 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22212662

RESUMO

Developing cavity-based supramolecular hydrogels is in its infancy because not many such hydrogelators are available. Reported herein is our creation of rigid cavitand cyclotriveratrylene (CTV) based hydrogelators from the molecular backbones of CTVs that were in limited cases shown to form organogels. For doing so deprotonable -COOH or protonable -NH(2) was introduced as terminal group into the rigid and hydrophobic CTV backbones. We thus successfully obtained optically anisotropic supramolecular hydrogels from these new CTVs hydrogelators with excellent thermostability and high tolerance towards strong electrolytes. The obtained CTV-1 and CTV-2 hydrogels are luminescent and exhibit reversible gel-to-sol and sol-to-gel transitions upon pH variations. The success in creating CTV-1 and CTV-2 hydrogelators on the basis of the skeleton of a CTV-organogelator suggests that balancing the hydrophilic and hydrophobic characters of the ionic and hydrophobic moieties well in the gelator molecule is important for designing a promising hydrogelator.

15.
Artigo em Chinês | MEDLINE | ID: mdl-21826900

RESUMO

OBJECTIVE: To explore the extraction methods of agglutinin from Oncomelania hupensis snail and study its haemagglutination activity. METHODS: Protein obtained by ammonium sulfate fractionation precipitation with 20%-100% saturation of ammonium sulfate. Its haemagglutination activity was determined by rabbit erythrocytes. The precipitation which could agglutinate rabbit erythrocytes was diluted with 2.5 mg/ml D-galactose, D-fructose, D-glucose, saccharose, maltose and lactose, respectively, and then their haemagglutination activity was tested. Snail agglutinin were incubated at different temperatures (25-90 degrees C) and assayed for agglutinating activity. The effect of pH on the haemagglutination activity was determined by using the PBS buffer at different pH values (3.0-10.0). RESULTS: Oncomelania snail agglutinin exhibited high haemagglutination activity in 20%-40% saturated ammonium sulfate pellet. Lactose and galactose could inhibit the haemagglutination activity of snail agglutinin. The agglutinin showed maximum activity at pH 7.0. In temperature range of 30-70 degrees C, the haemagglutination activity decreased with increasing temperature, and all activity lost beyond 80 degrees C. CONCLUSION: Galactose/lactose specific agglutinin exists in Oncomelania snail, its haemagglutination activity is affected by pH and temperature.


Assuntos
Aglutininas/isolamento & purificação , Aglutininas/metabolismo , Caramujos/química , Animais , Agregação Eritrocítica , Eritrócitos/efeitos dos fármacos , Hemaglutinação , Concentração de Íons de Hidrogênio , Coelhos , Temperatura
16.
Huan Jing Ke Xue ; 32(4): 1101-7, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21717754

RESUMO

The increasing pollution of organophosphorus pesticides (OP) in water have been of concerns. Taking the widely used triazophos as the object, a species sensitivity distribution (SSD) model was developed using a log-logistic distribution based on the median effective concentrations (EC50) of triazophos to aquatic species at various trophic levels, and then the model was tested and evaluated using probability plots and good-of-fit tests. The results showed that the SSD for aquatic biota exposed to triazophos was well fitted by a log-logistic distribution, which was totally determined by the two parameters, alpha = -0.4788 and beta = 0.7546, with standard error 0.2381 and 0.1078 respectively. Based on the SSD model, the hazardous concentration for 5% of the species (HC5) and the criteria maximum concentration (CMC) of triazophos were 1.992 x 10(-3) mg/L and 9.96 x 10(-4) mg/L, respectively. Through comparing the HC5 and CMC with the safe concentration for single-species, it could be found that environmental quality criteria derived from the SSD model was more strict, and closed to the real ecological environment. In addition, according to the reported data, the potentially affected fraction (PAF) of species exposed to triazophos in the Laizhou Bay (Bohai Sea, China) area was 0.36% predicted by the SSD model, and the corresponding risk might not be significant.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Organotiofosfatos/toxicidade , Triazóis/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biota , Chlorella/efeitos dos fármacos , Peixes , Água Doce/análise , Nível de Efeito Adverso não Observado , Medição de Risco , Especificidade da Espécie
17.
Ying Yong Sheng Tai Xue Bao ; 22(4): 1020-6, 2011 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-21774327

RESUMO

Fermentation pit is a kind of solid bioreactors with unique feature for brewing liquor, especially for Luzhou-flavor, which has significant effects on the quality of produced liquor. There exists a close and complicated correlation between pit age (using time) and microbial community. Taking the characteristic component phospholipid fatty acid (PLFA) in microbial cell membrane as an index, this paper studied the characteristics of the microbial community structure in the pit mud, fermented grains, and yellow water of different age (5-year, 100-year, and 300-year) fermentation pits. The results showed that the total PLFA content was the highest in pit mud, followed by in fermented grains, and in yellow water. The composition of PLFA differed with pit age, and the total PLFA content in yellow water decreased with increasing pit age. In pit mud, straight chain saturated fatty acid had the highest content, occupying 50.7-73.3% of total PLFA and being the highest in 300-year pit. As for the microbial community structure, the PLFA content characterizing Gram-positive (G+) anaerobic bacteria was higher in pit mud, and that characterizing Gram-negative (G-) anaerobic bacteria was higher in fermented grains and yellow water. The PLFA content characterizing G+ and G- bacteria in the pit mud of 100-year pit was higher than that in the pit mud of other ages' pits, while the PLFA content characterizing fungi was higher in the pit mud, fermented grains, and yellow water of 5-year pit, as compared with other ages' pits. Principal component analysis showed that the main varied microbial populations in 5- and 100-year pits were G- bacteria and fungi, and the main varied microbial population in 300-year pit was of bacteria. The indices frequency index, Simpson index, and Shannon index could be chosen for characterizing the diversity of microbial community in fermentation pits.


Assuntos
Bactérias/classificação , Reatores Biológicos/microbiologia , Fermentação , Fosfolipídeos/metabolismo , Vinho/microbiologia , Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Biodiversidade , Contagem de Colônia Microbiana , Ácidos Graxos/metabolismo , Dinâmica Populacional
18.
Chem Commun (Camb) ; 47(22): 6362-4, 2011 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-21541386

RESUMO

Developing of alternative chiral thiol stabilizers from the assembly of achiral thiol (e.g. thioglycolic acid) and chiral ligand (e.g. arginine) via both hydrogen bonding and electrostatic interactions was proposed and successfully applied to an efficient preparation of chiral CdS quantum dots (QDs). Chiral CdS QDs capped mainly with achiral thioglycolic acid were also obtained that may allow the chiral QDs to be modified for extended applications.


Assuntos
Compostos de Cádmio/química , Pontos Quânticos , Compostos de Sulfidrila/química , Sulfetos/química , Dicroísmo Circular , Ligação de Hidrogênio , Eletricidade Estática , Estereoisomerismo , Tioglicolatos/química
19.
Artigo em Chinês | MEDLINE | ID: mdl-24822347

RESUMO

OBJECTIVE: To isolate and purify agglutinin from Oncomelania hupensis snail and determine its molecular weight. METHODS: Agglutinin was preliminarily isolated from snail tissue homogenate by 0%-40% saturated ammonium sulfate, and then successively purified with Sephadex G-75 gel filtration and Sepharose 4B affinity chromatography. Bradford assay was used to determine the protein content. The agglutination activity was determined by rabbit erythrocytes. The purity of agglutinin preparations was assessed by SDS-PAGE. The molecular weight of agglutinin subunit was determined by Sephadex G-75 gel filtration. RESULTS: The specific activity of snail tissue homogenate was 21.74 titer/mg. After ammonium sulfate precipitation, Sephadex G-75 gel filtration and Sepharose 4B affinity chromatography, the specific activity of snail agglutinin from the homogenate solution increased to 61.93 titer/mg, 75.89 titer/mg and 963.86 titer/mg, respectively. SDS-PAGE analysis indicated that snail agglutinin (M, 53,000) was purified by Sephadex G-75 gel filtration and Sepharose 4B chromatography. The molecular weight of the snail agglutinin produced by Sephadex G-75 gel filtration was Mr 78,000. CONCLUSION: Combined use of salt fractionation, gel filtration and affinity chromatography can be efficient for extraction and purification of agglutinin from Oncomelania hupensis species. The snail agglutinin is characterized as mono subunit protein with a molecular weight of Mr 78,000.


Assuntos
Aglutininas/química , Aglutininas/isolamento & purificação , Caramujos/química , Animais , China , Cromatografia de Afinidade , Peso Molecular
20.
Chem Commun (Camb) ; 46(32): 5864-6, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-20517539

RESUMO

Substantially enhanced monosaccharide fluorescent sensing in aqueous solutions using a simple phenylboronic acid receptor is achieved by coupling the classic strategy based on saccharide-boronic acid interaction with catalytic Suzuki homocoupling reaction.


Assuntos
Ácidos Borônicos/química , Monossacarídeos/química , Catálise , Paládio/química , Espectrometria de Fluorescência
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