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1.
Biochem Biophys Res Commun ; 691: 149308, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38029542

RESUMO

This study tried to generate anti-idiotypic antibodies (Ab2s) which mimic Cry2Aa toxin using a phage-display antibody library (2.8 × 107 CFU/mL). The latter was constructed from a mouse immunized with F (ab')2 fragments digested from anti-Cry2Aa polyclonal antibodies. The F (ab')2 fragments and Plutella xylostella (P. xylostella) brush border membrane vesicles (BBMV) were utilized as targets for selection. Eight mouse phage-display single-chain variable fragments (scFvs) were isolated and identified by enzyme-linked immunoassay (ELISA), PCR and DNA sequencing after four rounds of biopanning. Among them, M3 exhibited the highest binding affinity with F (ab')2, while M4 bound the best with the toxin binding region of cadherin of P. xylostella (PxCad-TBR). Both of these two fragments were chosen for prokaryotic expression. The expressed M3 and M4 proteins with molecular weights of 30 kDa were purified. The M4 showed a binding affinity of 29.9 ± 2.4 nM with the PxCad-TBR and resulted in 27.8 ± 4.3 % larvae mortality against P. xylostella. Computer-assisted molecular modeling and docking analysis showed that mouse scFv M4 mimicked some Cry2Aa toxin binding sites when interacting with PxCad-TBR. Therefore, anti-idiotypic antibodies generated by BBMV-based screening could be useful for the development of new bio-insecticides as an alternative to Cry2Aa toxin for pest control.


Assuntos
Bacteriófagos , Inseticidas , Lepidópteros , Anticorpos de Cadeia Única , Animais , Camundongos , Biblioteca Gênica , Anticorpos de Cadeia Única/química , Endotoxinas/metabolismo , Anticorpos Anti-Idiotípicos , Biblioteca de Peptídeos
2.
J Invertebr Pathol ; 205: 108129, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38754546

RESUMO

Bacillus thuringiensis (Bt) Cry2Aa is a member of the Cry pore-forming, 3-domain, toxin family with activity against both lepidopteran and dipteran insects. Although domains II and III of the Cry toxins are believed to represent the primary specificity determinant through specific binding to cell receptors, it has been proposed that the pore-forming domain I of Cry2Aa also has such a role. Thus, a greater understanding of the functions of Cry2Aa's different domains could potentially be helpful in the rational design of improved toxins. In this work, cry2Aa and its domain fragments (DI, DII, DIII, DI-II and DII-DIII) were subcloned into the vector pGEX-6P-1 and expressed in Escherichia coli. Each protein was recognized by anti-Cry2Aa antibodies and, except for the DII fragment, could block binding of the antibody to Cry2Aa. Cry2Aa and its DI and DI-II fragments bound to brush border membrane vesicles (BBMV) from H. armigera and also to a ca 150 kDa BBMV protein on a far western (ligand) blot. In contrast the DII, DIII and DII-III fragments bound to neither of these. None of the fragments were stable in H. armigera gut juice nor showed any toxicity towards this insect. Our results indicate that contrary to the general model of Cry toxin activity domain I plays a role in the binding of the toxin to the insect midgut.


Assuntos
Toxinas de Bacillus thuringiensis , Proteínas de Bactérias , Endotoxinas , Proteínas Hemolisinas , Mariposas , Animais , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Toxinas de Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/metabolismo , Mariposas/metabolismo , Mariposas/microbiologia , Sítios de Ligação , Bacillus thuringiensis/metabolismo , Controle Biológico de Vetores , Domínios Proteicos , Helicoverpa armigera
3.
Biochem Biophys Res Commun ; 686: 149176, 2023 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-37924670

RESUMO

As skin injuries resulting from acute trauma, burns, and chronic diseases present significant challenges to healthcare systems worldwide, the promotion of skin wound healing remains an unmet therapeutic area. Dietary nitrate serves as a crucial pathway for the production of nitric oxide, which plays various physiological roles in the body, including vasodilation, increased blood flow, and antioxidant activity. However, the impact of dietary nitrate on skin wound healing remains uncertain. This study aimed to investigate the role of dietary nitrate in infected skin wound healing using a mouse model. We created a full-thickness wound infection model in mice and examine the effects of dietary nitrate (0.5 mmol/kg/d and 1 mmol/kg/d) on wound healing. The results demonstrated that dietary nitrate significantly increased serum nitrate and nitrite levels, leading to accelerated wound healing by increasing microvascular density, promoting collagen deposition and re-epithelialization. Moreover, nitrate supplementation exhibited a certain degree of reduction in inflammatory factors within the body. Our study also found that 1 mmol/kg/d nitrate has a more effective therapeutic effect and can increase blood perfusion and expedite the formation of new blood vessels, thereby promoting skin wound healing. These results indicate that dietary nitrate presents a novel therapeutic approach for infected skin wound healing.


Assuntos
Densidade Microvascular , Nitratos , Nitratos/metabolismo , Cicatrização , Pele/metabolismo , Colágeno/metabolismo
4.
BMC Plant Biol ; 23(1): 94, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36782126

RESUMO

The indica rice variety XYXZ carries elite traits including appearance and eating quality. Here, we report the de novo assembly of XYXZ using Illumine paired-end whole-genome shotgun sequencing and Nanopore sequencing. We annotated 39,722 protein-coding genes in the 395.04 Mb assembly. In comparison to other cultivars, XYXZ showed a larger gene size including the transcripts and introns, and more exons per gene. And hundreds of ultra-long genes were also detected. A total of 4362 complete LTRs were annotated, and among them, many were located next to or in protein-coding genes including several genes related to rice quality. We observed the different distributions of LTRs in these genes among XYXZ, Nipponbare, and R498, implying these LTRs might potentially affect expressions of the proximal genes and rice quality. Overall, This chromosome-length genome assembly of XYXZ provides a valuable resource for gene discovery, genetic variation and evolution, and the breeding of high-quality rice.


Assuntos
Genoma de Planta , Oryza , Oryza/genética , Melhoramento Vegetal , Sequenciamento Completo do Genoma , Cromossomos
5.
Opt Express ; 31(16): 25815-25828, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710457

RESUMO

The vertical profile of optical turbulence is a key factor in the performance design of astronomical telescopes and adaptive optics instruments. As site-testing campaigns are extremely expensive, the selection of appropriate spatial resolution data and estimation methods is extremely important. This study investigated the effect of using different methods (Dewan, HMNSP99, Thorpe method) to estimate the refractive index structure constant (C n2) using different resolution data (5 m, 25 m, ERA5 data) in Huaihua, Hunan. Compared with Dewan, HMNSP99 for estimating C n2 using 5 m and 25 m resolution data, the Thorpe method almost always shows the best performance, with RXY above 0.75 and lower RMSE and MRE between estimated and measured C n2. The results of C n2 estimation using HMNSP99 at different resolution data varied widely, indicating that HMNSP99 is more sensitive to the data resolution and the temperature gradient is more sensitive to the resolution. Using ERA5 data, the two methods of estimating C n2 using Dewan and HMNSP99 have close results. It indicates that the wind shear is the main factor when the spatial resolution of the data is reduced to a certain degree, and the contribution of temperature gradient is small in the high altitude turbulence.

6.
Anal Biochem ; 664: 115030, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36572217

RESUMO

Anti-idiotypic antibodies (Ab2) are valuable tools that can be used for a better understanding of molecular mimicry and the immunological network. In this work, we showed a new application of a phage-displayed alpha-type Ab2 (Ab2α) to improve the sensitivity of an enzyme-linked immunosorbent assay (ELISA) detecting cyanobacterial toxin microcystin-LR (MC-LR). A monoclonal antibody (mAb) against MC-LR was used as an antigen to isolate binders in a camelid nanobody library. After three rounds of panning, three unique clones with strong binding against anti-MC-LR mAbs were isolated. These clones could specifically bind to anti-MC-LR mAbs without influencing mAbs binding with MC-LR, meaning these clones were Ab2αs. Based on the signal amplification effect of phage coat proteins and the non-competitive nature of Ab2α, a novel competitive ELISA method for MC-LR was established with a phage-displayed Ab2α. It showed that the phage-displayed Ab2α greatly enhanced the ELISA signal and sensitivity of the method was improved 3.5-fold to the conventional one. Combining with the optimization of pre-incubation time, the optimized ELISA decreased its limit of detection (LOD) from 4.5 ng/mL to 0.8 ng/mL (5.6-fold improvement). This new application of Ab2α may potentially be employed to improve the sensitivity of immunoassays for other environmental pollutants.


Assuntos
Bacteriófagos , Biblioteca de Peptídeos , Ensaio de Imunoadsorção Enzimática/métodos , Imunoensaio , Anticorpos Monoclonais
7.
Appl Opt ; 62(4): 1115-1122, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36821172

RESUMO

Understanding turbulence in the free atmosphere is important for analyzing atmospheric pollution, forecasting weather, and light transmission. In this paper, we have tried to estimate the atmospheric refractive index structure constant C n2, the turbulent dissipation rate ε, and the turbulent diffusion coefficient K simultaneously during the experiment time over Lhasa, using the sounding data coupled with the Thorpe method. The result shows that the C n2 estimation gives a better performance with the correlation coefficients and the average relative error when compared with C n2 estimated by Dewan and HMNSP99. Besides this, the measured and estimated C n2, estimated ε, and K all show larger values in the troposphere, especially near the tropopause. It is worth noting that C n2 and ε are similar in terms of height distribution. These attempts at estimation all suggest that the Thorpe method can be used to estimate the intensity of turbulence in the free atmosphere over Lhasa.

8.
Gynecol Endocrinol ; 39(1): 2210232, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37187204

RESUMO

OBJECTIVE: To investigate the potential molecular mechanism of traditional Chinese medicine Guizhi Fuling Wan (GZFLW) inhibiting granulosa cells (GCs) autophagy in polycystic ovary syndrome (PCOS). METHODS: Control GCs and model GCs were cultured and treated with blank serum or GZFLW-containing serum. The levels of H19 and miR-29b-3p in GCs were detected using qRT-PCR, target genes of miR-29b-3p were identified using luciferase assay. The protein expressions of Phosphatase and tensin homolog (PTEN), Matrix Metalloproteinase (MMP)-2, and Bax were measured using western blot. The level of autophagy was detected via MDC staining, the degree of autophagosomes and autophagic polymers was observed using dual fluorescence-tagged mRFP-eGFP-LC3. RESULTS: GZFLW intervention reduced the expression of autophagy-related proteins PTEN, MMP-2 and Bax, by upregulating the expression of miR-29b-3p and downregulated the expression of H19 (p < .05 or p < .01). The number of autophagosomes and autophagy polymers was significantly decreased by GZFLW treatment. However, the inhibition of miR-29b-3p and overexpression of H19 induced a significant increase in the number of autophagosomes and autophagic polymers, which attenuated the inhibitory effect of GZFLW on autophagy (p < .05 or p < .01). In addition, inhibition of miR-29b-3p or overexpression of H19 can attenuate the effect of GZFLW on the expression of PTEN, MMP-2 and Bax proteins (p < .05 or p < .01). CONCLUSION: Our study found that GZFLW inhibits autophagy in PCOS GCs via H19/miR-29b-3p pathway.


Assuntos
MicroRNAs , Síndrome do Ovário Policístico , Animais , Feminino , Camundongos , Apoptose , Autofagia/genética , Proteína X Associada a bcl-2 , Proliferação de Células/genética , Células da Granulosa/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/metabolismo
9.
Anim Biotechnol ; 33(5): 981-991, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33325776

RESUMO

Circular RNA (circRNA) is a new non-coding RNA with a highly conserved and stable covalently closed loop structure, and it plays an important role in a variety of biological processes and the occurrence of diseases. Based on the sequencing results, circRNA_3079 had the most significant difference between the infected group and normal group, up to about 8 times. It has attracted our attention and was selected for further verification and analysis. Though the characteristics analysis of circRNA_3079 in chicken, we found circRNA_3079 is a stable, circular transcript, which mainly exists in the cytoplasm. And it is widely expressed in various tissues of chickens, and highly expressed in lung, spleen, lymph and bursa of fabricius. Bioinformatics analysis results showed that circRNA_3079 and the predicted target genes are enriched in many pathways related to immunity or tumors, such as p53 signaling pathway, Jak-STAT signaling pathway and NOD-like receptor signaling pathway, which revealed that circRNA_3079 may indirectly regulate the ALV-J infection process through the regulation of target genes.HIGHLIGHTSCircRNA_3079 is an abundant and stable circular RNA expressed in different tissues and cells in chicken.The circularization of circRNA_3079 does not depend on the reverse complementary repetitive sequence of the flanking sequence.CircRNA_3079 may indirectly regulate the ALV-J infection process.


Assuntos
Vírus da Leucose Aviária , Leucose Aviária , Animais , Leucose Aviária/genética , Vírus da Leucose Aviária/genética , Galinhas/genética , Proteínas NLR , RNA Circular/genética , RNA não Traduzido , Proteína Supressora de Tumor p53
10.
Anim Biotechnol ; 33(6): 1322-1332, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33752552

RESUMO

Totally, 315 42-day-old male Xueshan chickens were allocated into 3 caging densities, 14, 21 and 28 birds/m2. Each treatment was represented by 5 replicates. The body weight (BW), slaughter performance, meat quality, behavioral assessment, and the cecal microorganisms were detected at the market age. The results showed that the BW of broilers in the low- and medium-density groups was significantly higher (p < 0.05) than that of the high-density group from the age of 10 weeks. Only the feather quality of the broilers in the low-density group improved significantly (p < 0.05) compared with those of the other two groups. And, the abdominal fat percentage and the fat content of thigh muscle of broilers in the low- and medium-density groups were higher (p < 0.05) than those in the high-density group. No significant difference (p > 0.05) was noted in the other traits. The abundance of some microbial like Akkermansiaceae, Lactobacillaceae and Faecalibacterium may be correlated with the BW and fat content of broilers. The findings of this study suggest that increasing the stocking density decreased the final BW, fat content and the feather quality, whereas no evidence was found that stocking density caused changes in other parameters.


Assuntos
Criação de Animais Domésticos , Peso Corporal , Galinhas , Microbioma Gastrointestinal , Carne , Animais , Masculino , Criação de Animais Domésticos/métodos , Ceco/microbiologia , Carne/análise , Carne/normas , Densidade Demográfica
11.
Opt Lett ; 46(17): 4208-4211, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469976

RESUMO

Optical see-through head-mounted displays are actively developed in recent years. An appropriate method for mutual occlusion is essential to provide a decent user experience in many application scenarios of augmented reality. However, existing mutual occlusion methods fail to work well with a large field of view (FOV). In this Letter, we propose a double-parabolic-mirror structure that renders hard-edge occlusion within a wide FOV. The parabolic mirror increases the numerical aperture of the system significantly, and the usage of paired parabolic mirrors eliminates most optical aberrations. A liquid crystal on silicon device is introduced as the spatial light modulator for imaging a bright see-through view and rendering sharp occlusion patterns. A loop structure is built to eliminate vertical parallax. The system is designed to obtain a maximum monocular FOV of H114∘×V95∘ with hard-edge occlusion, and a FOV of H83.5∘×V53.1∘ is demonstrated with our bench-top prototype.

12.
Anal Biochem ; 625: 114222, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33932355

RESUMO

The anti-idiotypic antibody is widely used in the field of immunology to simulate structural features or even induce the biological activity of antigens. In this study, we obtained seven anti-idiotypic single-chain variable fragments (scFv) antibodies of Cry2Aa toxin from a phage-displayed mutant library constructed using error-prone PCR technique. A mutant designated 2-12B showed the best binding ability amongst all anti-idiotypic scFv isolates to Plutella xylostella brush border membrane vesicles (BBMVs). 2-12B and Cry2Aa toxin shared a potential receptor of polycalin in P. xylostella BBMVs. Homology modeling and molecular docking demonstrated that 2-12B and Cry2Aa toxin have seven common binding amino acid residues in polycalin. Insect bioassay results suggested that 2-12 had insecticidal efficacy against P. xylostella larvae. These results indicated that the Cry2Aa anti-idiotypic scFv antibody 2-12B partially mimicked the structure and function of Cry2Aa toxin. The anti-idiotypic scFv antibody provides the basic material for the future study of surrogate molecules or new insecticidal materials.


Assuntos
Anticorpos Anti-Idiotípicos/química , Anticorpos Monoclonais/química , Toxinas de Bacillus thuringiensis/química , Endotoxinas/química , Proteínas Hemolisinas/química , Região Variável de Imunoglobulina/química , Anticorpos de Cadeia Única/química , Animais , Anticorpos Anti-Idiotípicos/genética , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Anti-Idiotípicos/metabolismo , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Toxinas de Bacillus thuringiensis/imunologia , Toxinas de Bacillus thuringiensis/metabolismo , Membrana Celular/metabolismo , Endotoxinas/imunologia , Endotoxinas/metabolismo , Proteínas Hemolisinas/imunologia , Proteínas Hemolisinas/metabolismo , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Região Variável de Imunoglobulina/metabolismo , Simulação de Acoplamento Molecular , Mariposas , Mutação , Biblioteca de Peptídeos , Conformação Proteica , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/metabolismo
13.
Phys Chem Chem Phys ; 23(23): 12950-12957, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34086019

RESUMO

Concerted electron and proton transfer is a key step for the reversible conversion of molecular hydrogen in both heterogeneous nanocatalysis and metalloenzyme catalysis. However, its activation mechanism involving electron and proton transfer kinetics remains elusive. With the most widely used catalytic hydride reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) as a model reaction, we evaluate the catalytic activity of noble metal nanoparticles (NPs) trapped in porous silica in aqueous NaBH4 solution. By virtue of a novel combination of catalyst design, reaction kinetics, isotope labeling, and multiple spectroscopic techniques, the real catalytic site for the conversion of -NO2 to -NH2 is identified to be the water-hydroxyl transition metal complex, which could further react with NaBH4 to form a new triangular configuration metal complex of H3B-water-hydroxyl with dynamic features. It yields an ensemble of surface electronic states (SESs) though space overlapping of p orbitals of one B and several O atoms (including the O atoms of 4-NP), which could act as an alternative channel for concerted electron and proton transfer. This work highlights the critical role of the conceptual SESs model in heterogeneous catalysis to tune the chemical reactivity and also sheds light on the intricate working of the [FeFe]-hydrogenases.

14.
Appl Microbiol Biotechnol ; 104(17): 7345-7354, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32666189

RESUMO

Pyrethroids are insecticides that are widely used in rural and urban areas worldwide. After entering the environment, pyrethroids are rapidly metabolized or degraded by various biological or abiotic methods. In this study, a single-chain variable fragment (scFv) which could simultaneously detect three pyrethroid metabolites was constructed based on a hybridoma raised against 3-phenoxybenzoic acid (3-PBA). By molecular docking, it showed that there were hydrogen bonds, hydrophobic interactions, CH-π interaction, and cation-π interaction between 3-PBA and its scFv. All the contact residues contributing to hydrogen bonds are located in VH-CDR2 or its neighboring region, and two of them were mutants of the closest germline sequence. Based on competitive ELISA, the half maximal inhibitory concentration (IC50) of the scFv for 3-PBA, 3-phenoxybenzaldehyde (PBAld), and 3-phenoxybenzyl alcohol (PBAlc) were calculated to be 0.55, 0.59, and 0.63 µgmL-1, respectively. The scFv also showed 23.91%, 13.41%, 1.15%, 1.00%, and 0.56% cross-reactivity with phenothrin, deltamethrin, fenvalerate, beta-cypermethrin, and fenpropathrin. The broad specificity of the scFv may be due to its hapten design. The scFv could be employed in class-specific immunoassays for pyrethroid metabolites with phenoxybenzyl (PB) group. It is also potentially used for characterizing degradation of pyrethroids or detecting PBAlc (PBAld) alone, and the detection results should be confirmed by other selective methods. KEY POINTS: • A scFv which can simultaneously detect 3-PBA, PBAlc, and PBAld was constructed. • Antibody informatics and binding mode of the scFv were obtained. • The reason for its broad specificity was discussed. • It could be used to monitor single or multi-pyrethroid metabolites with PB group.


Assuntos
Inseticidas , Piretrinas , Anticorpos de Cadeia Única , Simulação de Acoplamento Molecular , Anticorpos de Cadeia Única/genética
15.
J Sci Food Agric ; 100(14): 5230-5238, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32519367

RESUMO

BACKGROUND: Black sweet corn as an edible fruit has various nutritional qualities. This study discusses changes in the vitamin C and E, folate, and carotenoid content during black sweet corn maturation, and also the effects of preharvest weather conditions and of related genes in multi-vitamin biosynthesis pathways. RESULTS: Most vitamin levels improved, especially vitamin C and carotenoid levels, while the folate content dropped rapidly. Transcript levels of most genes in folate biosynthesis showed trends that were similar to the content changes. VTC2 and GLDH, which are regulated by light, had high expression levels leading to an increase in ascorbate content during maturation. γ-Tocotrienol is the main vitamin E component, and HGGT, the key gene controlling the synthesis of tocotrienols, had a much higher expression level than other genes. Lutein and zeaxanthin were the dominant carotenoid components. A rapid reduction in the transcription level of LCYε could result in a lower lutein production rate . CONCLUSION: Black sweet corn has a high nutritional value and is rich in vitamins, including zeaxanthin, γ-tocotrienols, and ascorbic acid. The best harvest time is between 20-25 days after pollination (DAPs) when kernels had a good taste as well as relatively high vitamin levels. © 2020 Society of Chemical Industry.


Assuntos
Sementes/crescimento & desenvolvimento , Vitaminas/biossíntese , Zea mays/metabolismo , Carotenoides/análise , Carotenoides/metabolismo , Cor , Luteína/análise , Luteína/metabolismo , Sementes/química , Sementes/metabolismo , Tocotrienóis/análise , Tocotrienóis/metabolismo , Vitaminas/análise , Zea mays/química , Zea mays/crescimento & desenvolvimento , Zeaxantinas/análise , Zeaxantinas/metabolismo
16.
IUBMB Life ; 70(6): 553-562, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29626382

RESUMO

Patients with gastric ulcer (GU) have a significantly higher risk of developing gastric cancer (GC), especially within 2 years after diagnosis. The main way to improve the prognosis of GC is to predict the tumorigenesis and metastasis in the early stage. The objective of this study was to demonstrate the ability of human plasma amino acid metabolic profile for discriminating GC and GU. In this study, we first used liquid chromatography-tandem mass spectrometry technique to characterize the plasma amino acid metabolism in GC and GU patients. Plasma samples were collected from 84 GC patients and 82 GU patients, and 22 amino acids were detected in each patient. Partial least squares-discriminant analysis model was performed to analyze the data of these amino acids. We observed seven differential amino acids between GC and GU. A regression analysis model was established using these seven amino acids. Finally, a panel of five differential amino acids, including glutamine, ornithine, histidine, arginine and tryptophan, was identified for discriminating GC and GU with good specificity and sensitivity. The receiver operating characteristic curve was used to evaluate diagnostic ability of the regression model and area under the curve was 0.922. In conclusion, this study demonstrated the potential values of plasma amino acid metabolic profile and metabolomic analysis technique in assisting diagnosis of GC. More studies are needed to highlight the theoretical strengths of metabolomics to understand the potential metabolic mechanisms in GC. © 2018 IUBMB Life, 70(6):553-562, 2018.


Assuntos
Aminoácidos/metabolismo , Biomarcadores/metabolismo , Metaboloma , Neoplasias Gástricas/diagnóstico , Úlcera Gástrica/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Metabolômica , Pessoa de Meia-Idade , Curva ROC , Neoplasias Gástricas/metabolismo , Úlcera Gástrica/metabolismo
17.
Anal Biochem ; 518: 53-59, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27838242

RESUMO

Cry1Ie toxin was an insect-resistant protein used in genetically modified crops (GMC). In this study, a large human VH gene nanobodies phage displayed library was employed to select anti-Cry1Ie toxin antibody by affinity panning. After 5 rounds of panning, total 12 positive monoclonal phage particles were obtained. One of the identified positive phage nanobody was expressed in E.coli BL21 and the purified protein was indicated as a molecular mass of approximately 20 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Then a sensitive indirect competitive time-resolved fluoroimmunoassay (IC-TRFIA) was established for detection of Cry1Ie toxin by the purified protein. The working range of detection for Cry1Ie toxin standards in the IC-TRFIA were 0.08-6.44 ng mL-1 and the medium inhibition of control (IC50) was 0.73 ng mL-1. It showed a weak cross-reactivity with Cry1Ab toxin (at 5.6%), but did not recognize Cry1B, Cry1C, Cry1F, and Cry2A toxins (were <0.1%). The average recoveries of Cry1Ie toxin from respectively spiked in rice, corn and soil samples were in the range of 83.5%-96.6% and with a coefficient of variation (CV) among 2.0%-8.6%. These results showed the IC-TRFIA was promising for detection of Cry1Ie toxin in agricultural and environmental samples.


Assuntos
Bacillus thuringiensis/química , Proteínas de Bactérias/análise , Endotoxinas/análise , Análise de Alimentos/métodos , Proteínas Hemolisinas/análise , Oryza/química , Biblioteca de Peptídeos , Anticorpos de Domínio Único/química , Toxinas de Bacillus thuringiensis , Fluorimunoensaio/métodos , Humanos
18.
Anal Biochem ; 525: 89-91, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28274723

RESUMO

Soluble anti-bovine serum albumin (BSA) single-chain variable fragments (scFvs) were expressed in E. Coli. HB2151. The antigen-binding equilibrium dissociation constant of the scFvs was determined to be 2.9 × 10-8 M by surface plasmon resonance analysis. A competitive ELISA for the detection of BSA was developed using the antibody fragment above. The limits of detection (I10) and I50 were 0.002 and 0.74 µg/ml respectively, with a recovery between 87.8 and 119.2% in spiked milk samples. The assay has the potential to be used to detect concentration of BSA in milk or other matrix instead of the ELISA based on traditional antibodies.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Escherichia coli/metabolismo , Proteínas do Leite/análise , Leite/química , Soroalbumina Bovina/análise , Anticorpos de Cadeia Única/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Bovinos , Soroalbumina Bovina/imunologia , Ressonância de Plasmônio de Superfície
19.
IUBMB Life ; 68(12): 980-984, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27797142

RESUMO

Arginine is one of the human nonessential amino acids critical for the growth of human cancers. The aim of this study is to investigate the variation of arginine between breast cancer (BC) patients and benign mammary gland disease (control) patients to determine its value in predicting the risk of BC. We also explore the associations between arginine levels and breast cancer subtypes. Preoperative blood samples were obtained from 267 patients (102 BC and 165 controls) in 2015. Plasma arginine values were determined for all preoperative blood samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to analyse differences in arginine levels between BC patients and control patients and the correlations between arginine and clinicopathologic parameters in BC. The arginine levels of BC patients were significantly lower than those of control patients (5.96 [3.76-12.47] vs. 12.54 [7.14-24.94], P = 0.000). The area under the curve (AUC) for arginine was 0.721 (95% CI, 0.660-0.782, P < 0.0001). The concentration of arginine was significantly different among different molecular BC subtypes (P = 0.030). Our results suggested that plasma arginine was associated with breast cancer molecular subtypes. © 2016 IUBMB Life, 68(12):980-984, 2016.


Assuntos
Arginina/sangue , Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Estudos de Casos e Controles , China , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC
20.
IUBMB Life ; 68(10): 817-22, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27641058

RESUMO

Breast cancer (BC) is the most commonly diagnosed cancer in women worldwide. Arginine is a semiessential amino acid in humans and is essential for several biological pathways in malignant and normal cells, such as ornithine and N1, N12-diacetylspermine (DiAcSpm). This study aimed to determine the role of arginine and these downstream molecules in BC. Plasma arginine, ornithine, and arginine-to-ornithine ratio (AOR) were analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Urine samples were measured by the colloid gold aggregation to test determination of urinary diAcSpm. A principal component analysis was performed to evaluate the results observed between breast tumor and control characteristics. Differences in individual metabolite concentrations between BC patients and controls were tested by receiver operating characteristics (ROC) analyses. Student's t tests were used to detect the differences between two groups of normally distributed variables, and Wilcoxon sign rank tests were performed for asymmetrically distributed variables. As we analyzed, BC patients had lower plasma arginine and arginine/ornithine level, and higher plasma ornithine and urinary DiAcSpm concentrations as compared with control patients (P = 0.028, 0.020, 0.002, and 0.011, respectively). And the ROC curve was drawn and the area under the curve of the metabolites was calculated to be 0.659 (P = 0.028), 0.645 (P = 0.045), 0.7233 (P = 0.002), 0.683 (P = 0.011), respectively. In addition, our analysis showed that arginine concentrations and AOR had a positive correlation with ER status, while ornithine had a negative correlation with T stage (P = 0.042, 0.023, respectively).In conclusion, arginine and these downstream molecules were biomarkers for BC. More studies are needed to highlight the theoretical strengths. © 2016 IUBMB Life, 68(10):817-822, 2016.


Assuntos
Arginina/sangue , Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Ornitina/sangue , Adolescente , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Curva ROC , Espermina/análogos & derivados , Espermina/sangue , Adulto Jovem
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