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1.
J Pharm Biomed Anal ; 248: 116328, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38943819

RESUMO

Oxylipins are important low abundant signaling molecules in living organisms. In platelets they play a primary role in platelet activation and aggregation in the course of thrombotic events. In vivo, they are enzymatically synthesized by cyclooxygenases, lipoxygenases, or cytochrome P450 isoenzmes, resulting in diverse polyunsaturated fatty acid (FA) metabolites including hydroxy-, epoxy-, oxo-FAs, and endoperoxides with pro-thrombotic or anti-thrombotic effects. In a recent study, it was reported that hemin induces platelet death which was accompanied by enhanced reactive oxygen species (ROS) production (measured by flow cytometry) and lipid peroxidation (as determined by proxy using flow cytometry with BODIPY-C11 as sensor). Lipidomic studies further indicated significant changes of the platelet lipidome upon ex vivo hemin treatment, amongst others oxylipins were increased. The effect could be (at least partly) reversed by riociguat/diethylamine NONOate diethylammonium salt (DEA/NO) which modulates the soluble guanylate cyclase(sGC)-cGMP-cGMP-dependent protein kinase I(cGKI) signaling axis. In the original work, oxylipins were measured by a non-enantioselective UHPLC-tandem-MS assay which may not give the full picture whether oxylipin elevation is due to ROS or by enzymatic processes. We present here the study of the stereochemical disposition of hemin-induced platelet lipidome alterations using Chiralpak IA-U column with amylose tris(3,5-dimethylphenylcarbamate) chiral selector immobilized on 1.6 µm silica particles. It was found that the major platelet oxylipins 12-HETE, 12-HEPE and 14-HDoHE (from 12-LOX) and 12-HHT (from COX-1) were present in S-configuration indicating their enzymatic formation. On the other hand, both R and S enantiomers of 9- and 13-HODE, 11- and 15-HETE were detected, possibly due to enzyme promiscuity rather than non-specific oxidation (by ROS or autoxidation), as confirmed by multi-loop based two-dimensional LC-MS using selective comprehensive mode with achiral RPLC in the 1st dimension and chiral LC in the 2nd using a multiple heart-cutting interface. For 12-HETrE, a peak at the retention time of the R-enantiomer was ruled out as isobaric interference by 2D-LC-MS. In particular, arachidonic acid derivates 12(S)-HHT, 11(R)-HETE and 15(S)-HETE were found to be sensitive to hemin and cGMP modulation.


Assuntos
Plaquetas , GMP Cíclico , Hemina , Oxilipinas , Espectrometria de Massas em Tandem , Oxilipinas/farmacologia , Oxilipinas/química , Espectrometria de Massas em Tandem/métodos , Estereoisomerismo , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , GMP Cíclico/metabolismo , Humanos , Hemina/metabolismo , Hemina/química , Cromatografia Líquida/métodos , Espécies Reativas de Oxigênio/metabolismo , Lipidômica/métodos , Peroxidação de Lipídeos/efeitos dos fármacos
2.
Carbohydr Polym ; 327: 121617, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38171699

RESUMO

Glycans mediate various biological processes through carbohydrate-protein interactions, and glycan microarrays have become indispensable tools for understanding these mechanisms. However, advances in functional glycomics are hindered by the absence of convenient and universal methods for obtaining natural glycan libraries with diverse structures from glycoconjugates. To address this challenge, we have developed an integrative approach that enables one-pot release and simultaneously capture, separation, structural characterization, and functional analysis of N/O-glycans. Using this approach, glycoconjugates are incubated with a pyrazolone-type heterobifunctional tag-ANPMP to obtain glycan-2ANPMP conjugates, which are then converted to glycan-AEPMP conjugates. We prepared a tagged glycan library from porcine gastric mucin, soy protein, human milk oligosaccharides, etc. Following derivatization by N-acetylation and permethylation, glycans were subjected to detailed structural characterization by ESI-MSn analysis, which revealed >83 highly pure glycan-AEPMPs containing various natural glycan epitopes. A shotgun microarray is constructed to study the fine details of glycan-bindings by proteins and antisera.


Assuntos
Proteínas , Pirazolonas , Animais , Humanos , Suínos , Glicoconjugados , Polissacarídeos/química , Glicômica/métodos
3.
J Chromatogr A ; 1707: 464297, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37598531

RESUMO

Gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) can be used to detect the synthetic forms of endogenous anabolic androgenic steroids (EAAS) by comparing the 13C/12C ratios of the endogenous reference compound to that of the target compound. Isolation and enrichment of the target compound from urinary matrices is an essential prerequisite for the GC/C/IRMS confirmation procedure in doping control analysis. Boldenone (Bo) is a natural anabolic androgenic steroid (AAS) and a derivative of testosterone. The GC/C/IRMS confirmation procedure for Bo and its main metabolite 5ß-androst-1-en-17ß-ol-3-one (BoM) is extremely complicated due to the low concentrations and the enormously complex matrices in urine. The present study demonstrated a sample purification procedure for GC/C/IRMS by using online 2D-HPLC to purify Bo and BoM in urine samples. Bo and BoM with concentrations as low as 2 ng/mL were isolated and enriched with superior purity and selectivity. The validity of the method was verified with the technical document issued by the world anti-doping agency. The online 2D-HPLC purification procedure featured high selectivity for the analytes and no isotopic fractionation in the collection process. The present method can be used as a routine method allowing doping control laboratories to perform Boldenone confirmation.


Assuntos
Esteróides Androgênicos Anabolizantes , Testosterona , Cromatografia Gasosa-Espectrometria de Massas , Isótopos
4.
Biochem Biophys Rep ; 34: 101452, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36909453

RESUMO

d-Amino acids, rare enantiomers of amino acids, have been identified as biomarkers and therapeutic options for COVID-19. Methods for monitoring recovery are necessary for managing COVID-19. On the other hand, the presence of SARS-CoV2 virus in the blood is associated with worse outcomes. We investigated the potential of d-amino acids for assessing recovery from severe COVID-19. In patients with severe COVID-19 requiring artificial ventilation, the blood levels of d-amino acids, including d-alanine, d-proline, d-serine, and d-asparagine, which were lower than the normal range before treatment, quickly and transiently increased and surpassed the upper limit of the normal range. This increase preceded the recovery of respiratory function, as indicated by ventilation weaning. The increase in blood d-amino acid levels was associated with the disappearance of the virus in the blood, but not with inflammatory manifestations or blood cytokine levels. d-Amino acids are sensitive biomarkers that reflect the recovery of the clinical course and blood viral load. Dynamic changes in blood d-amino acid levels are key indicators of clinical course.

5.
J Chromatogr A ; 1685: 463599, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36345072

RESUMO

Glycomics analysis has been undermined by the lack of structurally defined individual glycans as model compounds. However, it is challenging to prepare individual glycans from natural resources, mainly due to separation difficulties caused by highly diverse structure, complicated mixture form and chromophore-free property of naturally-existing glycans. In this study, we report a simple, universal and low-cost glycan separation strategy, glycoselection, which allows preparation of individual reducing glycans from their mixtures through reversible chromogenic derivatization by hydrazide chemistry in combination with two-dimensional high-performance liquid chromatography (2D-HPLC). Investigations on reaction conditions using lactose and maltodextrin as model glycans showed the feasibility of reversible hydrazide labeling and one-pot hydrazone conversion under mild conditions, the good stability of hydrazone-form derivatives of glycans in solution and the difference among seven selected hydrazine-carrying chromogenic reagents in product yields during glycan labeling and post-column detagging. The 2D-HPLC separation conditions were established on maltodextrin, from which fourteen highly-purified individual reducing oligo-glucans were ultimately obtained. Using this strategy, we also successfully prepared and identified eleven individual neutral reducing N-glycans from chicken ovalbumin and thirteen individual neutral reducing oligosaccharides and eight individual sialylated ones from human milk, demonstrating its good applicability to different types of reducing glycans as well as biological samples. Given the compatibility of individual reducing glycans with almost all of glycan derivatization protocols and analytical techniques of glycans and the potential of the method for larger scale application, this work provides a universal approach to compound-specific analysis of natural glycans and has great significance for glycomics studies.


Assuntos
Glicômica , Hidrazonas , Humanos , Cromatografia Líquida de Alta Pressão , Glicômica/métodos , Polissacarídeos/química , Hidrazinas
6.
Anal Bioanal Chem ; 414(23): 6761-6769, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35895102

RESUMO

Due to the complex manufacturing process of therapeutic monoclonal antibodies, it is hardly possible to produce an identical copy of the original product (originator). Consequently, follow-on products (biosimilars) must demonstrate their efficacy being similar to the originator in terms of structure and function. During this process, a variety of analytical methods are required for this purpose. This study focuses on three particularly relevant analytical techniques: high-resolution mass spectrometry, fragment crystallisable (Fc) affinity chromatography, and two-dimensional peptide mapping. Each analytical method proved able to identify specific differences between originator and biosimilar. High-resolution mass spectrometry was used to characterize the glycan pattern. It was shown that a trastuzumab biosimilar did not have the G0:G0F sugar modification identified in the originator. The application of affinity chromatography to rituximab showed that originator and biosimilar interacted differently with the immobilized Fc receptor. Furthermore, 2D-HPLC peptide mapping demonstrated the influence of orthogonality of separation dimensions, leading to differentiation of a rituximab originator and biosimilar.


Assuntos
Antineoplásicos Imunológicos , Medicamentos Biossimilares , Anticorpos Monoclonais/química , Medicamentos Biossimilares/química , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Rituximab
7.
EClinicalMedicine ; 43: 101223, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34934934

RESUMO

BACKGROUND: Endogenous molecules that provide an unbiased and a precise evaluation of kidney function are still necessary. We explored the potential of clearance of d-serine, a rare enantiomer of serine and a biomarker of kidney function, as a measure of glomerular filtration rate (GFR). METHODS: This was a cross-sectional observational study of 200 living kidney transplant donors and recipients enrolled between July 2019 and December 2020 in a single Japanese center, for whom GFR was measured by clearance of inulin (C-in). Clearance of d-serine (C-dSer) was calculated based on blood and urine levels of d-serine, as measured by two-dimensional high-performance liquid chromatography. Analytical performance was assessed by calculating biases. Utilizing data from 129 participants, we developed equations for C-in based on C-dSer and C-cre using a linear regression model, and the performance was validated in 68 participants. FINDINGS: The means of C-in and C-dSer were 66.7 and 55.7 mL/min/1.73 m2 of body surface area, respectively, in the entire cohort. C-dSer underestimated C-in with a proportional bias of 22.0% (95% confidence interval, 14.2-29.8%) and a constant bias of -1.24 (-5.78-3.31), whereas the proportional bias was minor to that of C-cre (34.6% [31.1-38.2%] and 2.47 (-1.18-6.13) for proportional and constant bias, respectively). Combination of C-dSer and C-cre measured C-in with an equation of 0.391 × C-dSer + 0.418 × C-cre + 3.852, which reduced the proportional bias (6.5% [-0.2-13.1%] and -4.30 [-8.87-0.28] for proportional and constant bias, respectively). In the validation dataset, this equation performed well with median absolute residual of 3.5 [2.3-4.8], and high ratio of agreement (ratios of 30% and 15% different from C-in [P30 and P15] of 98.5 [91.4-100] and 89.7 [80.0-95.2], respectively). INTERPRETATION: The smaller proportional bias compared to that of C-cre is an advantage of C-dSer as a measure of C-in. Combinational measurement of d-serine and creatinine, two endogenous molecules, has the potential to serve as a measure of GFR with precision and minor biases and can support important clinical decisions. FUNDING: Japan Society for the Promotion of Science (JSPS, grant number 17H04188), Japan Agency of Medical Research and Development (AMED, JP20gm5010001), Osaka Kidney Bank (OKF19-0010), Shiseido Co., Ltd and KAGAMI Inc.

8.
Sichuan Mental Health ; (6): 424-428, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-987374

RESUMO

ObjectiveTo develop a two-dimensional high-performance liquid chromatography (2D-HPLC) for simultaneous determination of the contents of four kinds of Uncaria alkaloids: rhynchophylline, isorhynchophylline, corynoxeine and isocorynoxeine. MethodsThe 2D-HPLC apparatus was comprised of a first chromatographic column in version Aston SC2 (3.5 mm×25 mm, 5 μm), an intermediate column in version Aston SH C18 (3.5 mm×10 mm, 5 μm), and an analytical column in version Aston SCB (4.6 mm×125 mm, 5 μm). The mobile phase of the first and second liquid chromatography system were CAA-1 and mixed mobile phase (V BPI-1 basic mobile phase ∶ V MPI-1 mobile phase ∶ V OPI-1 organic mobile phase = 45∶14∶41). The chromatographic parameters included a flow rate of 1.0 mL/min, a column temperature of 40℃, a wavelength of 254 nm, an injection volume of 500 μL and a detection time of 9.5 min. ResultsThe linear ranges of rhynchophylline, isorhynchophylline, corynoxeine and isocorynoxeine were 9.77~10 000.00 ng/mL (r=0.999 6), 10.74~11 000.00 ng/mL (r=0.999 7), 10.74~11 000.00 ng/mL (r=0.999 7), 10.74~11 000.00 ng/mL(r=0.999 6), respectively. The relative standard deviation (RSD) of precision, stability and repeatability were all less than 5.00%. The accuracy was 95.20%~104.01%, and the recovery rate was 93.63%~101.38%. ConclusionThe 2D-HPLC developed for simultaneous determination of four kinds of alkaloids in Uncaria is simple and accurate, which can be used as a new method for quality control of Uncaria.

9.
Anal Bioanal Chem ; 413(28): 7119-7128, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34628527

RESUMO

Complete characterization and quantification of monoclonal antibodies often rely on enzymatic digestion with trypsin. In order to accelerate and automate this frequently performed sample preparation step, immobilized enzyme reactors (IMER) compatible with standard HPLC systems were used. This allows an automated online approach in all analytical laboratories. We were able to demonstrate that the required digestion time for the model monoclonal antibody rituximab could be reduced to 20 min. Nevertheless, a previous denaturation of the protein is required, which also needs 20 min. Recoveries were determined at various concentrations and were 100% ± 1% at 100 ng on column, 96% ± 7% at 250 ng on column and 98% ± 2% at 450 ng on column. Despite these good recoveries, complete digestion was not achieved, resulting in a poorer limit of quantification. This is 50 ng on column under optimized IMER conditions, whereas an offline digest on the same system achieved 0.3 ng on column. Furthermore, our work revealed that TRIS buffers, when used with an IMER system, led to alteration of the peptides and induced modifications in the peptides. Therefore, the addition of TRIS should be avoided when working at elevated temperatures of about 60 °C. Nevertheless, our results have shown that the recovery is not significantly influenced whether TRIS is used or not (recovery: 96 ± 7% with TRIS vs. 100 ± 9% without TRIS).


Assuntos
Anticorpos Monoclonais/análise , Reatores Biológicos , Enzimas Imobilizadas/química , Anticorpos Monoclonais/química , Automação , Desnaturação Proteica , Rituximab/análise , Rituximab/química , Tripsina/química
10.
Drug Discov Ther ; 15(3): 143-149, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34234063

RESUMO

An electrophysiological bioassay was used to isolate the active compound from Hochuekkito (HET), which the current authors previously described as having potent agonist action against serotonin 2C receptors (5-HT2CR). Synthetic 5-HT2CR mRNA was injected into Xenopus oocytes to specifically express these receptors. Crude extracts and purified products were subjected to an electrophysiological bioassay using the voltage clamp method. HET stimulated a 5-HT2CR-induced current response, whereas Juzentaohoto (JTT), which has anti-depressive action similar to that of HET, did not. Current responses were not observed with an extract mixed with five types of herbal medicines common to HET and JTT but were detected with an extract with the five types of herbal medicines found in HET alone (Hoc5). When the responses to each of the five types of Hoc5 were examined, current responses were noted with Cimicifugae rhizoma (CR) and Citrus unshiu Markovich extracts. Since efficacy and the EC50 value were higher for CR, its constituents were separated using three-dimensional high-performance liquid chromatography and the current response at each of the isolated peaks was examined. One constituent displayed a strong response and was identified as a single substance with a molecular weight of 283.1393 based on liquid chromatography/mass spectrometry. These results will contribute to the isolation of 5-HT2CR-stimulating constituents in HET and the identification of trace constituents with agonist action.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Oócitos/efeitos dos fármacos , Receptor 5-HT2C de Serotonina/fisiologia , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Animais , Bioensaio , Medicamentos de Ervas Chinesas/química , Fenômenos Eletrofisiológicos , Oócitos/fisiologia , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , RNA Mensageiro/administração & dosagem , Receptor 5-HT2C de Serotonina/genética , Serotonina/farmacologia , Agonistas do Receptor 5-HT2 de Serotonina/análise , Xenopus laevis
11.
J Pharm Biomed Anal ; 195: 113871, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33429251

RESUMO

For the enantiomer discriminated determination of lactate (LA) and 3-hydroxybutyrate (3HB) in various complicated samples, a three-dimensional HPLC (3D-HPLC) system has been designed and developed by investigating the separation of the target analytes from unknown substances observed in the real target matrices. LA and 3HB were pre-column derivatized with 4-nitro-7-piperazino-2,1,3-benzoxadiazole for the sensitive fluorescence detection and introduced into the 3D-HPLC system composed of reversed-phase, mixed-mode and enantioselective separations. The present method was validated by calibration curves, precision and accuracy using standard solutions and human samples, and sufficient values were obtained. Using the method, the levels of d-LA, l-LA, d-3Hb and l-3HB were determined, and their concentrations were 9.9, 1004.2, 79.7 and 2.1 µM in the human plasma and 16.0, 86.6, 8.7 and 4.8 µM in the human urine, respectively. The present 3D-HPLC system could selectively determine trace amounts of the target hydroxy acid enantiomers without disturbance of the intrinsic interfering substances in complicated matrices and the applications to various disease samples are expected.


Assuntos
Ácido Láctico , Ácido 3-Hidroxibutírico , Cromatografia Líquida de Alta Pressão , Humanos , Estereoisomerismo
12.
Drug Test Anal ; 13(2): 338-347, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32853478

RESUMO

19-Norandrosterone (19-NA) is the main metabolite of nandrolone and/or its precursors, which can be found naturally in human urine in trace amount. Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) confirmation procedure can be used to identify a potential exogenous origin of 19-NA in urine sample. Sample purification for GC-C-IRMS analysis is crucial to the whole confirmation procedure because the concentration of 19-NA in the urine to be tested is very low. Online two-dimensional high-performance liquid chromatography (2D-HPLC) clean-up procedure with high separation capacity is used to isolate and enrich 19-NA as a sample pretreatment process. Linearity, lowest detectable concentration, uncertainty, and selectivity of the method are validated according to the World Anti-doping Agency's (WADA) requirement. Isotope fractionation effect was not observed during the 2D-HPLC purification process. The validated method provides a high efficient and convenient confirmation procedure to determine the origin of 19-NA.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Estranos/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Desenho de Equipamento , Estranos/isolamento & purificação , Humanos , Limite de Detecção , Detecção do Abuso de Substâncias/métodos
13.
Biochim Biophys Acta Proteins Proteom ; 1868(9): 140463, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32512180

RESUMO

d-Amino acids, enantiomers of l-amino acids, are increasingly recognized as physiologically active molecules as well as potential biomarkers for diseases. d-Amino acid oxidase (DAO) catalyzes the oxidative deamination of d-amino acids and is present in a wide variety of organisms from yeasts to humans. Previous studies indicated that LEA rats lacked DAO activity, and levels of d-Ser and d-Ala were markedly increased in their tissues, suggesting a mutated locus responsible for the lack of Dao activity (ldao) existed in the LEA genome. Sequence analysis identified deletion breakpoints located in intron 4-5 of the Dao gene and intron 1-2 of the Svop gene, resulting in a 54.1-kb deletion which encompassed exons 5-12 of the Dao gene and exons 2-16 of the Svop gene. We developed a novel congenic rat strain, F344-Daoldao, harboring the Daoldao mutation from LEA rats delivered onto the F344 genetic background. Compared to the parental F344 strain, in F344-Daoldao rats d-Ala was markedly increased in both cerebrum and cerebellum, while d-Ser content was increased in cerebellum but not cerebrum. d-Ala, d-Ser, d-Pro and d-Leu levels were also elevated in F344-Daoldao plasma. F344-Daoldao rats represent a novel model system that will aid in elucidating the physiological functions of d-amino acids in vivo. (203 words).


Assuntos
D-Aminoácido Oxidase/genética , D-Aminoácido Oxidase/metabolismo , Mutação , Aminoácidos/metabolismo , Animais , Regulação da Expressão Gênica no Desenvolvimento , Rim , Masculino , Ratos , Ratos Endogâmicos F344 , Análise de Sequência de DNA , Transcriptoma
14.
Mol Biol (Mosk) ; 53(6): 982-997, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31876277

RESUMO

The CRISPR/Cas system is currently widely used for genome editing. The procedure of genome editing includes two necessary steps: (i) searching for the most effective guide RNA, and (ii) analyzing clones for presence of the desired mutation. This review presents the methods used to assess the efficiency of the CRISPR/Cas system and to confirm mutation in the target locus and discusses their advantages and disadvantages. It aims to provide information that could help researchers to choose a technique most appropriate for their specific tasks and available resources.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Edição de Genes/normas
15.
J Pharm Biomed Anal ; 175: 112758, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31330279

RESUMO

Flos Lonicerae Japonicae(Jinyinhua) possesses clearing heat and detoxification activity, and has been used as a traditional Chinese medicine to treat influenza for many years. Due to the complex chemical composition and diverse content of Jinyinhua, especially the many trace ingredients, the effective components are unknown. In this study, an improved two-dimensional high performance liquid chromatography-ultrafiltration combined with electrospray ionization-time-of-flight/mass spectroscopy (ESI-TOF/MS) approach was designed and used for the enrichment, screening and characterization of minor neuraminidase inhibitors in Jinyinhua. In the first dimension, semi-prep-HPLC was employed for the preliminary separation of different polarity components and enrichment of low content components from Jinyinhua extract. In the second dimension, hydrophilic interaction liquid chromatography and reverse phase-HPLC were used to separate the different polar fractions, respectively. The fractions then underwent ultrafiltration and ESI-TOF/MS for the comprehensive screening and characterization of potential neuraminidase inhibitors. As a result, a total of 44 compounds were found to have neuraminidase inhibitory activity, and 22 of these compounds were preliminarily identified by accurate molecular weight and UV absorption data compared with standards and references. The activity of 16 of these compounds was verified by the neuraminidase inhibition assay. This study provides support for the rapid screening of minor neuraminidase inhibitors from complex natural medicines.


Assuntos
Inibidores Enzimáticos/química , Neuraminidase/antagonistas & inibidores , Extratos Vegetais/química , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Lonicera/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Ultrafiltração/métodos
16.
J Forensic Leg Med ; 61: 108-114, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30553228

RESUMO

INTRODUCTION: Short Tandem Repeats (STRs) are defined as short lengths of 2-7 base pairs spreading through human genome which due to their highly diverse individually distribution are widely applied for identity detection and other forensic medicine purposes. Burdening considerable costs by the conventional methods such as capillary electrophoresis, we aimed to compare concomitant usage of multiplex PCR and denaturing high-performance liquid chromatography (DHPLC) as cheap, fast, highly accurate, and more accessible methods, with capillary electrophoresis (CE) to evaluate their potential for early screening of STRs. MATERIALS AND METHODS: The present study randomly included 20 blood samples from the subjects referred to forensic medicine of Semnan, Iran. According to the size and allele frequency, we selected 8 major STR loci including CSF1PO, VWA, D18S51, TPOX, Amelogenin, FGA, SE33, and Penta D. A quad-STR multiplex PCR was performed for each locus and the PCR products were then analyzed using DHPLC machine and compared with the basic genetic properties obtained by capillary electrophoresis. RESULTS: By optimizing the PCR and DHPLC conditions, our findings suggest this strategy as an effective method for STR detection. The genotypes were determined using size of loci which led to comparable results with capillary electrophoresis confirming an insignificant variation in the detection of TOPX, Amelogenin, CSF1PO, and D18S5 (p = 0.331), but discrepant results for FGA and VWA loci (p = 0.002). CONCLUSION: Our study proposed DHPLC method as an effective screening method to characterize TOPX, Amelogenin, CSF1PO, and D18S51 as frequently used STR loci during identity detection in forensic medicine.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Impressões Digitais de DNA , Repetições de Microssatélites , Amelogenina/genética , Eletroforese Capilar , Humanos , Reação em Cadeia da Polimerase Multiplex
17.
Anal Biochem ; 553: 24-27, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29777680

RESUMO

The plant hormone abscisic acid (ABA) regulates many processes, including response to drought, seed dormancy and abscission of leaves and fruits. For maintenance of ABA homeostasis, catabolism of ABA by 8'-hydroxylation and subsequent cyclisation to phaseic acid (PA) is crucial. However, detection of ABA 8'-hydroxylation activity is tedious. We present a simple and rapid method for detection of ABA 8'-hydroxylase activity by cloning cDNAs of interest and expressing the respective protein in yeast. Upon addition of ABA, PA is formed and subsequently quantified in the yeast cell culture supernatant by heart cutting 2D-HPLC or GC-MS.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Proteínas de Plantas/metabolismo , Plantas/enzimologia , Saccharomyces cerevisiae/enzimologia , Ciclização
18.
J Appl Glycosci (1999) ; 65(4): 45-49, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-34354512

RESUMO

To study the structure of ß-glucans, we developed a separation method and molecular library of ß-glucan oligosaccharides. The oligosaccharides were prepared by partial acid hydrolysis from laminarin, which is a ß-glucan of Laminaria digitata. They were labeled with the 2-aminopyridine fluorophore and separated to homogeneity by size-fractionation and reversed phase high-performance liquid chromatography (HPLC). Branching structures of all isomeric oligosaccharides from trimers to pentamers were determined, and a two-dimensional (2D)-HPLC map of the ß-glucan oligosaccharides was made based on the data. Next, structural analysis of the longer ß-glucan oligosaccharide was performed using the 2D-HPLC map. A branched decamer oligosaccharide was isolated from the ß-glucan and cleaved to smaller oligosaccharides by partial acid hydrolysis. The structure of the longer oligosaccharide was successfully elucidated from the fragment structures determined by the 2D-HPLC map. The molecular library and the 2D-HPLC map described in this study will be useful for the structural analysis of ß-glucans.

19.
Cytokine ; 103: 99-108, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28982581

RESUMO

The correlation of interleukin 10 (IL-10) with the outbreak and progression of cancer has been well established as it contributes to tumor immune evasion. Convincing number of evidences has been accumulated to reflect the critical correlation between IL-10 polymorphism and tumorogenesis. Several polymorphic sites at promoter regions have been reported to be associated with cancer susceptibility. The purpose of this study was to examine the effect of modulated genotypes in the promoter region of IL-10 gene with life-style habits in oral squamous cell carcinoma (OSCC) in the Indian population. A total of 300 subjects (100 OSCC, 50 precancer and 150 healthy controls) were recruited in this study. The IL-10 promoter region was amplified in 14 overlapping fragments by PCR and further screened through the high throughput technique of denaturing high-performance liquid chromatography (dHPLC) followed by sequencing. We identified three novel variations at positions (-924, -1045 & -1066); we also found some known SNPs (-592C/A, -657G/A, -851G/A, -819C/T, -1082A/G). The identified novel variations were submitted to the NCBI Gene Bank (accession numbers KT153594, KT291742 and KT291743). We also noticed a significant association of polymorphisms (-592C/A, -819C/T and -1082A/G) individually as well as in combination (haplotypes) along with lifestyle habits for the risk of oral carcinoma (p<0.0001). We have reported three novel SNPs in the Indian population for the first time, and these SNPs may be associated with OSCC. Besides, we showed the first evidence of IL-10 haplotypes, i.e., CCG and CTG, may act as a biomarker for early detection of oral pre-cancerous/cancerous lesions or treatment management of oral carcinoma.


Assuntos
Carcinoma de Células Escamosas/genética , Interleucina-10/genética , Neoplasias Bucais/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-28178596

RESUMO

Monoclonal antibodies are mainly produced by mammalian cell culture, which due to its complexity, results in a wide range of product variants/isoforms. With the growing implementation of Quality by Design (QbD) and Process Analytical Technology (PAT) in drug manufacturing, monitoring and controlling quality attributes within a predefined range during manufacturing may provide added consistency to product quality. To implement these concepts, more robust analytical tools could reduce the time needed for monitoring quality attributes during upstream processing. The formation of protein aggregates is one such quality attribute that can lead to safety and efficacy issues in the final drug product. Described in this study is a fully automated two-dimensional high performance liquid chromatography (2D-HPLC) method for characterizing protein aggregation of crude in-process bioreactor samples. It combines protein A purification and separation by size exclusion into a single analytical module that has the potential to be employed at-line within a bioprocessing system. This method utilizes a novel in-line fraction collection device allowing for the collection of up to twelve fractions from a single sample or peak which facilitates the subsequent linked analysis of multiple protein peaks of interest in one chromatography module.


Assuntos
Anticorpos Monoclonais , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Anticorpos Monoclonais/análise , Anticorpos Monoclonais/química , Anticorpos Monoclonais/isolamento & purificação , Cromatografia em Gel/instrumentação , Cromatografia em Gel/métodos , Desenho de Equipamento , Agregados Proteicos , Proteína Estafilocócica A/análise , Proteína Estafilocócica A/química , Proteína Estafilocócica A/isolamento & purificação
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