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1.
Bioorg Med Chem ; 27(8): 1728-1741, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30862430

RESUMO

We efficiently synthesized 2'-O,4'-C-aminomethylene-bridged nucleic acid (2',4'-BNANC) monomers bearing the four nucleobases, guanine, adenine, thymine, and 5-methylcytosine and incorporated these monomers into oligonucleotides. Initially, we carried out the transglycosylation reaction on several 2'-O-substituted 5-methyluridines to evaluate the effects of 2'-substitutions on this reaction. Under the optimized conditions, purine nucleobases were successfully introduced, and 2',4'-BNANC monomers bearing adenine or guanine were obtained over several steps. In addition, the improved synthesis of the 2',4'-BNANC monomers bearing thymine or 5-methylcytosine was also achieved. The obtained 2',4'-BNANC monomers were subsequently incorporated into oligonucleotides and the duplex-forming abilities of the modified oligonucleotides were investigated. Duplexes containing 2',4'-BNANC monomers in both or either strands were found to possess excellent thermal stabilities.


Assuntos
5-Metilcitosina/química , Adenina/química , Hidrocarbonetos Aromáticos com Pontes/química , Guanina/química , Nucleotídeos/química , Oligonucleotídeos/síntese química , Glicosilação , Oligonucleotídeos/química , Timina , Temperatura de Transição , Raios Ultravioleta
2.
Fish Physiol Biochem ; 45(1): 231-243, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30387032

RESUMO

Cadmium (Cd) is known to be a potentially toxic heavy metals to the fish health and growth. Carassius auratus gibelio (C. a. gibelio) specimens were exposed to waterborne Cd (0, 0.05, 0.10, 0.15, and 0.20 mg/L CdCl2) for 14 days. Cd accumulation, liver and intestine histopathology, and intestinal microorganism were investigated in the present study. The results indicated that Cd accumulation in the gill, liver, intestine, and muscle gradually decreased as Cd concentration increased. The gill accumulated higher amounts of Cd than other tissues. The histopathology of liver and intestine underwent changes with different Cd concentrations, including hepatocyte hypertrophy, aggregation of blood cells, sinusoids, lipidosis, necrosis of hepatic tissues, the erosion of villi, necrosis in the mucosal layer, the appearance of vacuoles in the lamina propria, hyperplasia, and swelling of goblet cells. Moreover, the core gut microbiota existed in the intestinal microorganism and did not change as Cd concentration increased. However, the diversity of intestinal microorganism was significantly reduced compared with that of the control sample. The present results indicated that C. a. gibelio exposed to Cd suffered toxicity, and Cd could affect the biodiversity of the intestinal microbiota of C. a. gibelio.


Assuntos
Cádmio/metabolismo , Cádmio/toxicidade , Carpa Dourada , Intestinos/microbiologia , Poluentes Químicos da Água/toxicidade , Animais , Brânquias , Intestinos/efeitos dos fármacos
3.
J BUON ; 23(4): 919-924, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30358194

RESUMO

PURPOSE: To investigate the efficacy of ultrasonic elastography in the qualitative diagnosis of malignant and benign breast tumors. METHODS: The study included 200 female patients with benign (n=100) and breast carcinomas (n=100) treated between January 2015 and March 2017. Each patient underwent ultrasonic elastography before surgery and registration of the hardness score and lesion area diameter. Postoperatively the diagnosis was pathologically confirmed. RESULTS: The hardness scores of the benign group were below 3 points while in the malignant group was above 2 points (p <0.05). The average scores of the benign and breast carcinoma groups were 2.4±1.1 and 4.3±0.7 points, respectively. The lesion areas of the malignant group were 2.44 ± 1.63 cm2 and of the benign group 1.03 ± 1.01 cm2 (p <0.05). The accuracy, sensitivity, specificity, positive predictive value, negative predictive value and area under the curve (AUC) of ultrasonic elastography in the qualitative diagnosis of breast carcinoma were 86.73, 88.62, 84.47, 87.20, 86.14% and 91%, respectively. CONCLUSION: In the qualitative diagnosis of benign and breast carcinomas, ultrasonic elastography can contribute to the accurate diagnosis of the disease and can be used with success in clinical practice.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Adulto , Idoso , Neoplasias da Mama/patologia , Técnicas de Imagem por Elasticidade/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Pesquisa Qualitativa , Ultrassonografia/métodos , Adulto Jovem
4.
Langmuir ; 34(18): 5334-5341, 2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29665686

RESUMO

Recently, although several unconventional luminescent polymers have been synthesized, it still remains a significant challenge to prepare various new fluorescent polymers by functionalization of nonfluorescent polymers. A nonfluorescent 1 H,1 H,2 H,2 H-perfluoro-1-decanol grafted to nonfluorescent polystyrene- b-poly(acrylic acid) block copolymers through simply esterification reaction can exhibit strong blue emission. On the basis of control experiments and theoretical simulation, we have proposed that the luminescence stems from interchain n → π* interaction between the lone pair (n) of hydroxyl O atoms of carboxyl units and empty π* orbital of ester carbonyl unit. In addition, the fluorescent polymers are successfully employed for fluorescence imaging in living HeLa cell.

5.
J Agric Food Chem ; 65(30): 6179-6187, 2017 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-28654282

RESUMO

Our previous study indicated that pretreatment by dynamic high-pressure microfluidization (DHPM) and glycation with galactose was a promising method for decreasing the immunoglobulin E (IgE)-binding ability of ß-lactoglobulin (ß-LG). In this work, the conformational alteration of ß-LG subjected to DHPM and glycation treatment was investigated in relation to IgE-binding ability by orbitrap mass spectrometry. After DHPM pretreatment, lower IgE-binding ability of glycated ß-LG was observed with increasing pressures. Prior to DHPM pretreatment, 11 glycated sites were identified, while the number of glycation sites was increased to 12 after pretreatment. However, there was no significant difference of the glycation sites at the pressures of 50, 100, and 200 MPa, respectively. Average degree of substitution per peptide molecule of ß-LG (DSP) was investigated to assess the degree of glycation per glycation site. All of the samples pretreated by DHPM exhibited a higher glycation level than those without DHPM pretreatment. The shielding effects of epitopes owing to glycation contributed to the reduction of IgE-binding capacity. Orbitrap mass spectrometry could provide a comprehensive understanding of the nature of protein glycation.


Assuntos
Imunoglobulina E/química , Lactoglobulinas/química , Espectrometria de Massas/métodos , Glicosilação , Imunoglobulina E/metabolismo , Lactoglobulinas/metabolismo , Microfluídica , Peptídeos/química , Peptídeos/metabolismo , Pressão , Ligação Proteica , Conformação Proteica
6.
J Food Sci Technol ; 53(8): 3253-3270, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27784920

RESUMO

Ginger and garlic have long been used in Asian countries to enhance the flavor and to neutralize any unpleasant odors present in fish soup. The purpose of this study was to evaluate the change in the amount of volatile components present in fish soup compared to boiled water solutions of ginger and garlic. The fish soup was prepared by boiling oil-fried grass carp (Ctenopharyngodon idella) with or without ginger and/or garlic. Generally, boiling garlic and ginger in water led to a decrease in the amount of the principal volatile constituents of these spices, together with the formation of some new volatiles such as pentanal, hexanal, and nonanal. The results showed that 16 terpenes present in raw ginger, predominantly camphene, ß-phellandrene, ß-citral, α-zingiberene, and (E)-neral, were detected in fish soup with added ginger and thus remained in the solution even after boiling. Similarly, 2-propen-1-ol and three sulfur compounds (allyl sulfide, diallyl disulfide, and diallyl trisulfide) present in raw garlic, were present in trace amounts in the boiled garlic solution, but were present in considerably larger amounts in the boiled fish solution with garlic or garlic plus ginger. In conclusion, the effect of adding spices on the volatile profile of grass carp soup can be attributed to the dissolution of flavor volatiles mainly derived from raw spices into the solution, with few additional volatiles being formed during boiling. In addition, boiling previously fried grass carp with spices led to enhanced volatile levels compared to boiled spice solutions.

7.
Food Res Int ; 89(Pt 1): 882-888, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28460991

RESUMO

The effects of dynamic high-pressure microfluidization (DHPM) (80, 120, and 160MPa) treatment and glycation with galactose on the IgE-binding capacity and conformation of ß-lactoglobulin (ß-Lg) were investigated. The binding capacity of immunoglobulin E (IgE) from patients' sera with cow's milk allergy on ß-Lg glycated with galactose decreased after DHPM treatment. ß-Lg treated after different DHPM methods and pressures yielded a significant discrepancy in IgE-binding capacity. When ß-Lg was pretreated by DHPM, the IgE-binding capacity of ß-Lg-galactose conjugates decreased with increasing pressure; however, the conjugates showed higher IgE-binding capacity at 120MPa than that at 80 and 160MPa when the ß-Lg-galactose mixture was treated by DHPM. Results of thermal properties, intrinsic fluorescence spectroscopy, surface hydrophobicity, and circular dichroism (CD) spectra indicated the occurrence of protein unfolding, as well as the tertiary and secondary structural changes of ß-Lg. The results suggested pretreatment by DHPM and glycation with galactose was a promising approach for eliminating the IgE-binding capacity of ß-Lg.

8.
Bioorg Med Chem ; 19(3): 1162-6, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21256033

RESUMO

Using the copper(I)-catalyzed alkyne-azide 1,3-dipolar cycloaddition, a post-elongation modification of 1-ethynyl substituted nucleobases has been employed to construct 18 variations of oligonucleotides from a common oligonucleotide precursor. The triplex-forming ability of each oligonucleotide with dsDNA was evaluated by the UV melting experiment. It was found that triazole nucleobases generally tend to exhibit binding affinities in the following order: CG>TA>AT, GC base pairs. Among the triazole nucleobases examined, a 1-(4-ureidophenyl)triazole provided the best result with regard to affinity and selectivity for the CG base pair.


Assuntos
DNA/química , Oligonucleotídeos/química , Oligonucleotídeos/síntese química , Compostos de Fenilureia/síntese química , Triazóis/síntese química , Azidas/química , Pareamento de Bases , Desenho de Fármacos , Compostos Heterocíclicos , Compostos de Fenilureia/química , Triazóis/química
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