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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 265: 120344, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34481145

RESUMO

In this paper, terahertz (THz) spectra of four DNA nucleosides (Adenosine, Thymidine, Cytidine and Guanosine) and two nucleoside derivatives (Ribavirin and Entecavir, first time reported) in the solid phase were studied experimentally by Fourier Transform Infrared Spectroscopy (FTIR) in the frequency of 1-10 THz. The lattice energy, geometric structure, vibration spectrum of them were analyzed theoretically by the generalized energy-based fragmentation approach under periodic boundary conditions (denoted as PBC-GEBF) and the density functional theory (DFT). The intra- and inter-molecular weak interactions corresponding to the vibrational modes of the crystal, polymer and monomer were obtained, with the help of the potential energy distribution (PED) and reduced density gradient (RDG) methods. It was found that the sum of electronic and thermal free energies increased from the monomer to polymer, and from the polymer to crystal. For example, the inter-molecular interaction energy from the monomer to dimer of adenosine increased 6.969 kcal/mol, and that from the dimer to crystal (the periodic boundary conditions were considered) increased 666.792 kcal/mol. Therefore, only the crystal structure constrained the periodic boundary conditions could well describe the experimental results, although the former scholars chose the monomer or polymer as the initial configuration due to the limitation of computing resources and methods. In THz band, the vibrational modes were generally originated from the collective vibration (more than 99% of them were vibration, only less than 1% of them were rotation and translation) of all molecules involved, which could reflect the molecular structure and spatial distribution of different substances. In order to accurately identify the spectra, we studied the location, type and contribution of all weak interactions, and found that the strong characteristic peaks corresponding to the strong hydrogen bonds came from inter-molecular, while the weak hydrogen bonds mainly originated from intra- and inter-molecular, the out-of-plane bending made the largest contribution, accounting for more than 90%. Furthermore, taking guanine, guanosine and two guanosine derivatives (Ribavirin and Entecavir) as examples, the differences of weak interaction among them caused by different molecular configuration, arrangement and substituent position were studied, and the fundamental reason of THz spectrum change was found. This research can lay a foundation for crystal engineering, supramolecular chemistry, molecular recognition and self-assembly, protein-ligand interaction, etc.


Assuntos
Preparações Farmacêuticas , Espectroscopia Terahertz , Ligação de Hidrogênio , Nucleosídeos , Vibração
2.
Curr Protoc ; 1(11): e307, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34792865

RESUMO

This protocol describes a step-by-step chemical synthesis approach to prepare N3 -methylcytidine (m3 C) and its phosphoramidite. The method for synthesizing m3 C starts from commercially available cytidine, and proceeds via N3 -methylation in the presence of MeI, which generates the N3 -methylcytidine (m3 C) nucleoside, followed by the installation of several protecting groups at sites that include the 5'-hydroxyl group (4,4'-dimethoxytrityl protection), the 4-amino group (benzoyl protection), and the 2'-hydroxyl group (tert-butyldimethylsilyl, TBDMS, protection). Standard phosphoramidite chemistry is applied to prepare the final m3 C phosphoramidite for solid-phase synthesis of a series of RNA oligonucleotides. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Synthesis of N3 -methylcytidine (m3 C) and its phosphoramidite Basic Protocol 2: Automated synthesis of m3 C modified RNA oligonucleotides.


Assuntos
Oligonucleotídeos , RNA , Citidina , Nucleosídeos , Técnicas de Síntese em Fase Sólida
3.
Curr Protoc ; 1(11): e281, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34748276

RESUMO

Ribavirin analogs substituted at position 5 of the heterocyclic base are interesting for their biological activity. This protocol describes a synthetic route to several such ribavirin analogs with a wide range of substituents.© 2021 Wiley Periodicals LLC. Basic Protocol 1: Synthesis and purification of 5-substituted ethyl 1,2,4-triazole-3-carboxylates - synthetic precursors of nucleobases Basic Protocol 2: Synthesis and purification of protected 1,2,4-triazole nucleoside analogs Basic Protocol 3: Synthesis and purification of 5-substituted ribavirin analogs.


Assuntos
Ribavirina , Triazóis , Ácidos Carboxílicos , Nucleosídeos
4.
Molecules ; 26(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34770855

RESUMO

In the last two years, nucleosides analogues, a class of well-established bioactive compounds, have been the subject of renewed interest from the scientific community thanks to their antiviral activity. The COVID-19 global pandemic, indeed, spread light on the antiviral drug Remdesivir, an adenine C-nucleoside analogue. This new attention of the medical community on Remdesivir prompts the medicinal chemists to investigate once again C-nucleosides. One of the essential building blocks to synthetize these compounds is the D-(+)-ribono-1,4-lactone, but some mechanistic aspects linked to the use of different carbohydrate protecting groups remain unclear. Here, we present our investigations on the use of benzylidene as a ribonolactone protecting group useful in the synthesis of C-purine nucleosides analogues. A detailed 1D and 2D NMR structural study of the obtained compounds under different reaction conditions is presented. In addition, a molecular modeling study at the B3LYP/6-31G* level of theory with the SM8 solvation model for CHCl3 and DMSO to support the obtained results is used. This study allows for clarifying mechanistic aspects as the side reactions and structural rearrangements liked to the use of the benzylidene protecting group.


Assuntos
Compostos de Benzilideno/química , Lactonas/química , Nucleosídeos/síntese química , Ribose/análogos & derivados , Adenina/análogos & derivados , Antivirais/química , COVID-19/tratamento farmacológico , COVID-19/prevenção & controle , Humanos , Lactonas/síntese química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Nucleosídeos/metabolismo , Nucleosídeos de Purina , Ribose/síntese química , Ribose/química , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Estereoisomerismo
5.
PLoS One ; 16(10): e0258198, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34618855

RESUMO

In southern Ontario, Canada, the two-spotted spider mite (Tetranychus urticae) is an emerging pest of soybean (Glycine max) due to the increasing incidence of warmer, drier weather conditions. One key strategy to manage soybean pests is breeding resistant cultivars. Resistance to pathogens and herbivores in soybean has been associated with isoflavonoid phytoalexins, a group of specialized metabolites commonly associated with root, leaf and seed tissues. A survey of 18 Ontario soybean cultivars for spider mite resistance included evaluations of antibiosis and tolerance in relation to isoflavonoid and other metabolites detected in the leaves. Ten-day and 4-week trials beginning with early growth stage plants were used to compare survival, growth, fecundity as well as damage to leaves. Two-spotted spider mite (TSSM) counts were correlated with HPLC measurements of isoflavonoid concentration in the leaves and global metabolite profiling by high resolution LC-MS to identify other metabolites unique to the most resistant (R) and susceptible (S) cultivars. Within 10 days, no significant difference (P>0.05) in resistance to TSSM was determined between cultivars, but after 4 weeks, one cultivar, OAC Avatar, was revealed to have the lowest number of adult TSSMs and their eggs. Other cultivars showing partial resistance included OAC Wallace and OAC Lakeview, while Pagoda was the most tolerant to TSSM feeding. A low, positive correlation between isoflavonoid concentrations and TSSM counts and feeding damage indicated these compounds alone do not explain the range of resistance or tolerance observed. In contrast, other metabolite features were significantly different (P<0.05) in R versus S cultivars. In the presence of TSSM, the R cultivars had significantly greater (P<0.05) concentrations of the free amino acids Trp, Val, Thr, Glu, Asp and His relative to S cultivars. Furthermore, the R cultivar metabolites detected are viable targets for more in-depth analysis of their potential roles in TSSM defense.


Assuntos
Resistência à Doença/imunologia , Interações Hospedeiro-Parasita , Doenças das Plantas/imunologia , Doenças das Plantas/parasitologia , Soja/imunologia , Soja/parasitologia , Tetranychidae/fisiologia , Aminoácidos/análise , Animais , Flavonoides/análise , Herbivoria/fisiologia , Metabolômica , Nucleosídeos/análise , Peptídeos/análise , Folhas de Planta/química , Análise de Componente Principal , Soja/crescimento & desenvolvimento
6.
Se Pu ; 39(9): 1006-1011, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34486840

RESUMO

Currently, guanosine, adenosine, and uridine contents are specified as the quality criteria for related products in the quality standards for fermented Cordyceps powder preparations included in the 2020 edition of Chinese Pharmacopoeia. However, there are many other nucleosides in fermented Cordyceps powder, whose effect on the quality control has not yet been discussed. In this study, an ultra-performance liquid chromatography-ultraviolet detection (UPLC-UV) method was used for the quantitative analysis of 9 nucleosides (uracil, cytidine, guanidine, uridine, adenine, inosine, guanosine, thymidine, and adenosine) in 19 batches of fermented Cordyceps powder samples and products, and the corresponding fingerprints were established. In addition, a method for analyzing the index components was proposed based on statistics. By optimizing the sample extraction method, ultrasound-assisted extraction was selected to process 19 batches of samples. Chromatographic analysis was performed on an Agilent Eclipse Plus C18 column (150 mm×4.6 mm, 3.5 µm) using methanol and water as the mobile phases under gradient elution. The method was validated based on the calibration curves, accuracy, precision, repeatability, and recovery. The fingerprints of the 19 batches of samples were established, and 16 common peaks were obtained. Among them, nine nucleoside peaks were identified by standards, and their concentrations were determined by the external standard one-point method. Similarity evaluation of the fingerprints was conducted; the similarities of the 19 batches of samples were greater than 0.9. Then, chemical pattern recognition was performed. The same classification results were obtained by hierarchical clustering analysis (HCA) and principal component analysis (PCA). Thus, the samples could be segregated into five classes, and the fermented Cordyceps powders were classified as two types with different fermentation processes. Xinganbao capsules, Bailing capsules and Ningxinbao capsules were each separately classified into one class. This indicated that the chemical recognition pattern could effectively distinguish between the fermented Cordyceps powder and different products. PCA was used to calculate the weight value of each common peak for the first time, and the index components among the samples were selected according to the weight value. Finally, the selected index components were used to re-cluster the samples. The results were consistent with those obtained on the basis of the 16 common peaks, thus verifying the rationality of the index components. Therefore, uridine, guanosine, adenosine, adenine, and uracil are recommended for use as evaluation indicators for fermented Cordyceps powder and products, allowing for better distinction between the products on the market. In summary, the combination of liquid chromatographic fingerprints and chemical pattern recognition can provide a simple and reliable method for the analysis and quality control of fermented Cordyceps powder and products.


Assuntos
Cordyceps , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Nucleosídeos , Pós , Análise de Componente Principal
7.
Zhongguo Zhong Yao Za Zhi ; 46(12): 2912-2922, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34467681

RESUMO

The dried fruit body of Phylloporia ribis(Hymenochaetaceae), which prefers to live on the stumps of Lonicera japonica(Caprifoliaceae), has a variety of activities, whereas its pharmacodynamic material basis is not completely clear and there are few reports on its quality control and evaluation. In this study, an UPLC-Q-TOF-MS method was used to analyze the nucleosides and nucleobases in P. ribis and a HPLC method was established for simultaneous determination of 10 nucleosides and nucleobases. MS and MS/MS data were acquired in positive ion mode. Based on the data comparison of the sample and the reference substance, the literature data and the compound databases of ChemSpider and PubChem, 18 nucleosides and nucleobases were identified qualitatively from the water extract of P. ribis for the first time. After optimization, the HPLC was performed using a Welch Ultimate AQ C_(18) column(4.6 mm×250 mm, 5 µm) by gradient elution with acetonitrile and water as mobile phase, the flow rate of 1.0 mL·min~(-1), the detection wavelength of 260 nm, and the column temperature of 30 ℃. Through the investigation of the extraction method, solvent and time, it was determined that the test solution should be obtained by cold water extraction for 18 h. At the present HPLC conditions, 10 components of uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine and thymidine could be well separated(R > 1.5) and showed good linearity(r > 0.999 9) in the concentration ranges of 0.247-24.7, 0.283-28.3, 0.273-27.3, 0.256-25.6, 0.257-25.7, 0.318-31.8, 0.245-24.5, 0.267-26.7, 0.250-25.0 and 0.267-26.7 mg·L~(-1), respectively. The average reco-veries of 10 components were 95.78%-104.5%, and the RSDs were 2.2%-5.2%(n=6). The contents of 10 nucleosides and nucleobases in different samples of P. ribis varied greatly, which were 0.021-0.122, 0.004-0.029, 0.014-0.226, 0.009-0.442, 0.003-0.014, 0.002-0.146, 0.007-0.098, 0-0.054, 0.005-0.069, 0.004-0.081 and 0.072-1.28 mg·g~(-1) for uracil, cytidine, hypoxanthine, uridine, thymine, inosine, guanosine, 2'-deoxyinosine, 2'-deoxyguanosine, thymidine and total 10 components, respectively. These results demonstrated that the components had significant differences in the internal quality, and good quality control was needed to ensure the medical efficacy. This study provides a scientific basis for the discovery of pharmacodynamic ingredients, quality control and evaluation of P. ribis.


Assuntos
Nucleosídeos , Espectrometria de Massas em Tandem , Basidiomycota , Cromatografia Líquida de Alta Pressão , Guanosina
8.
Curr Protoc ; 1(9): e248, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34529364

RESUMO

This article summarizes the protocols for phosphoramidite chemistry and solid phase synthesis of RNA oligonucleotides containing N4 -methylcytidine (m4 C) and N4 ,N4 -dimethylcytidine (m4 2 C) residues for base-pairing, structural, and enzymatic activity studies. The two key m4 C and m4 2 C phosphoramidite building blocks can be synthesized starting from the partially protected cytidine nucleosides, followed by solid-phase synthesis and HPLC purification of the modified target RNA oligonucleotides. These modified RNA strands are then prepared for base pairing stability, specificity, and structural studies using UV-melting temperature (Tm ) measurements and X-ray crystallography. Functional studies are performed by reverse transcription assays in primer extension reactions employing different enzymes. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Chemical synthesis of m4 C phosphoramidite Basic Protocol 2: Synthesis of m4 2 C phosphoramidite Basic Protocol 3: Synthesis and purification of m4 C and m4 2 C containing RNA oligonucleotides.


Assuntos
Citidina , RNA , Pareamento de Bases , Nucleosídeos , Oligonucleotídeos
9.
Sci Rep ; 11(1): 17953, 2021 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504157

RESUMO

A new series of nucleosides, moieties, and Schiff bases were synthesized from sulfadimidine. Infrared (IR), 1HNMR, 13C NMR, and mass spectrometry techniques and elemental analysis were employed to elucidate the synthesized compounds. The prepared analogues were purified by different chromatographic techniques (preparative TLC and column chromatography). Molecular docking studies of synthesized compounds 3a, 4b, 6a, and 6e demonstrated the binding mode involved in the active site of DNA gyrase. Finally, all synthesized compounds were tested against selected bacterial strains. The most effective synthesized compounds against S. aureus were 3a, 4d, 4b, 3b, 3c, 4c, and 6f, which exhibited inhibition zones of inhibition of 24.33 ± 1.528, 24.67 ± 0.577, 23.67 ± 0.577, 22.33 ± 1.528, 18.67 ± 1.528 and 19.33 ± 0.577, respectively. Notably, the smallest zones were observed for 4a, 6d, 6e and 6g (6.33 ± 1.528, 11.33 ± 1.528, 11.67 ± 1.528 and 14.66 ± 1.155, respectively). Finally, 6b and 6c gave negative zone values. K. pneumoniae was treated with the same compounds and the following results were obtained. The most effective compounds were 4d, 4c, 4b and 3c, which showed inhibition zones of 29.67 ± 1.528, 24.67 ± 0.577, 23.67 ± 1.155 and 19.33 ± 1.528, respectively, followed by 4a and 3d (15.33 ± 1.528 for both), while moderate results (13.67 ± 1.155 and 11.33 ± 1.528) were obtained for 6f and 6g, respectively. Finally, 6a, 6b, 6c, 3a, and 3b did not show any inhibition. The most effective compounds observed for the treatment of E. coli were 4d, 4b, 4c, 3d, 6e and 6f (inhibition zones of 26.33 ± 0.577, 21.67 ± 1.528, 21.67 ± 1.528, 19.67 ± 1.528, 17.67 ± 1.155 and 16.67 ± 1.155, respectively). Compounds 3b, 3c, 6a, 6c, and 6g gave moderate results (13.67 ± 1.528, 12.67 ± 1.528, 11.33 ± 0.577, 15.33 ± 1.528 and 12.67 ± 1.528, respectively), while 6b showed no effect. The MIC values against S. aureus ranged from 50 to 3.125 mg, while those against E. coli and K. pneumoniae ranged from 50 to 1562 mg. In vitro, the antibacterial effects were promising. Further research is required to study the in vivo antibacterial effects of these compounds and determine therapeutic doses.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Simulação de Acoplamento Molecular/métodos , Nucleosídeos/química , Nucleosídeos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Sulfametazina/análogos & derivados , Domínio Catalítico , DNA Girase/metabolismo , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana/métodos , Nucleosídeos/síntese química , Bases de Schiff/química , Relação Estrutura-Atividade
10.
Antiviral Res ; 195: 105180, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34551346

RESUMO

Galidesivir (BCX4430) is an adenosine nucleoside analog that is broadly active in cell culture against several RNA viruses of various families. This activity has also been shown in animal models of viral disease associated with Ebola, Marburg, yellow fever, Zika, and Rift Valley fever viruses. In many cases, the compound is more efficacious in animal models than cell culture activity would predict. Based on favorable data from in vivo animal studies, galidesivir has recently undergone evaluation in several phase I clinical trials, including against severe acute respiratory syndrome coronavirus 2, and as a medical countermeasure for the treatment of Marburg virus disease.


Assuntos
Adenina/análogos & derivados , Adenosina/análogos & derivados , Antivirais/farmacologia , Pirrolidinas/farmacologia , Adenina/farmacologia , Adenosina/farmacologia , Animais , Ensaios Clínicos Fase I como Assunto , Avaliação Pré-Clínica de Medicamentos , Marburgvirus/efeitos dos fármacos , Nucleosídeos/análogos & derivados , SARS-CoV-2/efeitos dos fármacos
11.
Chemistry ; 27(59): 14738-14746, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34432342

RESUMO

Fluoro-substitution on the ribose moiety (e. g., 2'-F-deoxyribonucleotide) represents a popular way to modulate the ribose conformation and, hence, the structure and function of nucleic acids. In the present study, we synthesized 4'-F-deoxythymidine (4'-F T) and introduced it to oligodeoxyribonucleotides (ODNs). Though scission of the glycosylic bond of 4'-F T followed by strand cleavage occurred to some extent under alkaline conditions, the 4'-F T-modified ODNs were rather stable in neutral buffers. NMR studies showed that like 2'-F-deoxyribonucleoside, 4'-F T exists predominantly in the North conformation not only in the nucleoside form but also in the context of ODN strands. Circular dichroism spectroscopy, thermal denaturing and RNase H1 footprinting studies of 4'-F T-modified ODN/cDNA and ODN/cRNA duplexes indicated that the North conformation tendency of 4'-F T is maintained in the duplexes, leading to a local structural perturbation. Collectively, 4'-F-deoxyribonucleotide structurally resembles the 2'-F-deoxyribonucleotide but imparts less structural perturbation to the duplex than the latter.


Assuntos
Nucleosídeos , Oligodesoxirribonucleotídeos , Dicroísmo Circular , Conformação Molecular , Conformação de Ácido Nucleico
12.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445114

RESUMO

The strong decoration of tRNAs with post-transcriptional modifications provides an unprecedented adaptability of this class of non-coding RNAs leading to the regulation of bacterial growth and pathogenicity. Accumulating data indicate that tRNA post-transcriptional modifications possess a central role in both the formation of bacterial cell wall and the modulation of transcription and translation fidelity, but also in the expression of virulence factors. Evolutionary conserved modifications in tRNA nucleosides ensure the proper folding and stability redounding to a totally functional molecule. However, environmental factors including stress conditions can cause various alterations in tRNA modifications, disturbing the pathogen homeostasis. Post-transcriptional modifications adjacent to the anticodon stem-loop, for instance, have been tightly linked to bacterial infectivity. Currently, advances in high throughput methodologies have facilitated the identification and functional investigation of such tRNA modifications offering a broader pool of putative alternative molecular targets and therapeutic avenues against bacterial infections. Herein, we focus on tRNA epitranscriptome shaping regarding modifications with a key role in bacterial infectivity including opportunistic pathogens of the human microbiome.


Assuntos
Bactérias/genética , Bactérias/patogenicidade , Transcriptoma/genética , Anticódon/genética , Humanos , Nucleosídeos/genética , Biossíntese de Proteínas/genética , Processamento Pós-Transcricional do RNA/genética , RNA de Transferência/genética , Virulência/genética
13.
Biomed Pharmacother ; 142: 111953, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34343897

RESUMO

Currently, there are over 230 different COVID-19 vaccines under development around the world. At least three decades of scientific development in RNA biology, immunology, structural biology, genetic engineering, chemical modification, and nanoparticle technologies allowed the accelerated development of fully synthetic messenger RNA (mRNA)-based vaccines within less than a year since the first report of a SARS-CoV-2 infection. mRNA-based vaccines have been shown to elicit broadly protective immune responses, with the added advantage of being amenable to rapid and flexible manufacturing processes. This review recapitulates current advances in engineering the first two SARS-CoV-2-spike-encoding nucleoside-modified mRNA vaccines, highlighting the strategies followed to potentiate their effectiveness and safety, thus facilitating an agile response to the current COVID-19 pandemic.


Assuntos
Engenharia Biomédica , Vacinas contra COVID-19 , COVID-19 , Desenvolvimento de Medicamentos/métodos , Descoberta de Drogas/métodos , SARS-CoV-2 , Engenharia Biomédica/métodos , Engenharia Biomédica/tendências , COVID-19/prevenção & controle , COVID-19/virologia , Vacinas contra COVID-19/classificação , Vacinas contra COVID-19/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Humanos , Imunogenicidade da Vacina , Lipossomos/farmacologia , Nanopartículas , Nucleosídeos/farmacologia , Nucleosídeos/fisiologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Sintéticas/farmacologia
15.
Vet Microbiol ; 260: 109186, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34333402

RESUMO

Replication of peste des petits ruminants virus (PPRV) strongly depends on the cellular environment and resources of host cells including nucleoside pool. Thus, enzymes involved in nucleoside biosynthesis (such as pyrimidine biosynthesis pathway) are regarded as attractive targets for antiviral drug development. Here, we demonstrate that brequinar (BQR) and leflunomide (LFM) which are two specific inhibitors of DHODH enzyme and 6-azauracil (6-AU) which is an ODase enzyme inhibitor robustly inhibit PPRV replication in HEK293T cell line as well as in peripheral blood mononuclear cells isolated from goat. We further demonstrate that these agents exert anti-PPRV activity via the depletion of purimidine nucleotide. Interestingly, these inhibitors can trigger the transcription of antiviral interferon-stimulated genes (ISGs). However, the induction of ISGs is largely independent of the classical JAK-STAT pathway. Combination of BQR with interferons (IFNs) exerts enhanced ISG induction and anti-PPRV activity. Taken together, this study reveals an unconventional novel mechanism of crosstalk between nucleotide biosynthesis pathways and cellular antiviral immunity in inhibiting PPRV replication. In conclusion, targeting pyrimidine biosynthesis represents a potential strategy for developing antiviral strategies against PPRV.


Assuntos
Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Nucleosídeos/metabolismo , Peste dos Pequenos Ruminantes/virologia , Vírus da Peste dos Pequenos Ruminantes/fisiologia , Animais , Compostos de Bifenilo/farmacologia , Células HEK293 , Humanos , Imunidade Celular , Interferons/farmacologia , Leflunomida/farmacologia , Leucócitos Mononucleares/imunologia , Vírus da Peste dos Pequenos Ruminantes/efeitos dos fármacos , Vírus da Peste dos Pequenos Ruminantes/imunologia , Pirimidinas/metabolismo , Uracila/análogos & derivados , Uracila/farmacologia , Replicação Viral
16.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3337-3348, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34396753

RESUMO

A high performance liquid chromatography( HPLC) method was established for the fast,and precise determination of ten nucleosides in Fritillariae Cirrhosae Bulbus and its counterfeits. Then multivariate statistical analyses,such as clustering analysis,principal component analysis( PCA),and Fisher' s linear discriminant analysis( LDA),were conducted to establish a discriminant function model for an integrated analysis. The results indicated that data acquisition time of a single sample was shortened within 16 min by the HPLC method. In the range of 5-1 000 mg·kg~(-1),the mass concentrations of all nucleosides exhibited good linear relationships with the corresponding peak areas( R2> 0. 999). The spiked recoveries were in the range of 93. 83%-108. 9% with RSDs of0. 12%-1. 3%( n = 5). The limit of quantitation( LOQ) was 0. 98-4. 13 mg·kg~(-1). As revealed by the clustering analysis,Fritillariae Cirrhosae Bulbus and the counterfeits could be discriminated into two clusters based on the content of nucleosides. Fisher's LDA could achieve this discrimination,while PCA dimension reduction failed. The accuracy of the discriminant function model established on the screened characteristic indicators reached 97. 5%. The present study proposed a new identification method of Fritillariae Cirrhosae Bulbus with one-dimensional indicators,which is simple,accurate,and reliable. It can provide a scientific basis for further optimizing the identification techniques for Fritillariae Cirrhosae Bulbus and inspiration for quality control strategy development of Chinese medicinal materials.


Assuntos
Medicamentos de Ervas Chinesas , Fritillaria , Cromatografia Líquida de Alta Pressão , Nucleosídeos , Raízes de Plantas
17.
Zhongguo Zhong Yao Za Zhi ; 46(14): 3494-3503, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34402271

RESUMO

In order to reveal the regional characteristics of nucleosides and amino acids in Elaphuri Davidiani Cornu,39 samples of Elaphuri Davidiani Cornu collected from 4 different regions were analyzed by UPLC-QTRAP ~®/MS2 method followed by orthogonal partial least-squares discrimination analysis( OPLS-DA) and cluster analysis( CA). The results showed all the samples contained abundant nucleosides and amino acids,with the total content of 45. 09 µg·g~(-1) and 634. 80 µg·g-1,respectively. The samples presented significant regional differences in the contents of individual components,and the main differential components included Ura,Hpro,Thr,Glu,G5 P,2'-dG,Adeno,Met,Ade,Gln,Orni,Phe,2'-dA,Hit,Lys,and Ile. Among them,Ura,Met,Glu,and Ile had the highest content in the samples from Dafeng in Jiangsu,Qinhu in Jiangsu,Beijing,and Shishou in Hubei,respectively. OPLS-DA and CA demonstrated that all the samples of Elaphuri Davidiani Cornu could be divided into three categories,reflecting the regional characteristics. The results indicated that the accumulation of nucleosides and amino acids in Elaphuri Davidiani Cornu was closely related to its habitat,providing a useful reference for the research on the quality formation,quality evaluation and control,as well as the comprehensive utilization of Elaphuri Davidiani Cornu. The findings suggested that the content factors of Ura,Met,Glu,and Ile could be included into the quality standard system of Elaphuri Davidiani Cornu as the characteristics of medicinal materials from different regions.


Assuntos
Cornus , Aminoácidos , Pequim , Nucleosídeos
18.
BMC Pregnancy Childbirth ; 21(1): 551, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34384374

RESUMO

BACKGROUND: We encourage Hepatitis B virus-infected mothers to breastfeed postpartum, even when continuing pregnancy category B nucleos(t)ide analogs (NAs) treatment. However, a large proportion of the Hepatitis B virus-infected mothers were noncompliant with this breastfeeding recommendation. This study aimed to investigate the factors associated with noncompliance with breastfeeding recommendation in Hepatitis B virus-infected mothers who had received NAs treatment during pregnancy. METHODS: A total of 155 mothers with chronic hepatitis B receiving NAs treatment for preventing mother-to-child transmission during the late gestation period were included and divided into exclusive breastfeeding (n = 63), mixed feeding (n = 34), and artificial feeding (n = 58) groups according to the postpartum feeding methods. Independent variables associated with feeding methods were analyzed using logistic regression analysis. RESULTS: Compared to the breastfeeding and mixed feeding groups, the artificial feeding group had significantly more multiparity, later postpartum timing of stopping NAs treatment, and a lower proportion of having knowledge of NAs medications (all P < 0.05). In addition, multivariable logistic regression analysis confirmed that multiparity, later postpartum timing of stopping NAs treatment, and lacking knowledge of medication were independent factors associated with noncompliance with breastfeeding recommendation. CONCLUSIONS: Hepatitis B virus-infected mothers who stopped NAs treatment at late postpartum period or had less knowledge of medication were more likely to be noncompliant with breastfeeding recommendation. Strengthening health education for participants taking NAs may be an important method to improve compliance with breastfeeding recommendation.


Assuntos
Antivirais/uso terapêutico , Aleitamento Materno , Nucleosídeos/uso terapêutico , Cooperação do Paciente , Período Pós-Parto , Telbivudina/uso terapêutico , Tenofovir/uso terapêutico , Adulto , China/epidemiologia , Feminino , Hepatite B Crônica/prevenção & controle , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Estudos Retrospectivos , Fatores de Risco
19.
Biomolecules ; 11(6)2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198819

RESUMO

Drugs targeting DNA and RNA in mammalian cells or viruses can also affect bacteria present in the host and thereby induce the bacterial SOS system. This has the potential to increase mutagenesis and the development of antimicrobial resistance (AMR). Here, we have examined nucleoside analogues (NAs) commonly used in anti-viral and anti-cancer therapies for potential effects on mutagenesis in Escherichia coli, using the rifampicin mutagenicity assay. To further explore the mode of action of the NAs, we applied E. coli deletion mutants, a peptide inhibiting Pol V (APIM-peptide) and metabolome and proteome analyses. Five out of the thirteen NAs examined, including three nucleoside reverse transcriptase inhibitors (NRTIs) and two anti-cancer drugs, increased the mutation frequency in E. coli by more than 25-fold at doses that were within reported plasma concentration range (Pl.CR), but that did not affect bacterial growth. We show that the SOS response is induced and that the increase in mutation frequency is mediated by the TLS polymerase Pol V. Quantitative mass spectrometry-based metabolite profiling did not reveal large changes in nucleoside phosphate or other central carbon metabolite pools, which suggests that the SOS induction is an effect of increased replicative stress. Our results suggest that NAs/NRTIs can contribute to the development of AMR and that drugs inhibiting Pol V can reverse this mutagenesis.


Assuntos
DNA Polimerase Dirigida por DNA/genética , Proteínas de Escherichia coli/genética , Mutagênese/efeitos dos fármacos , Nucleosídeos/análogos & derivados , Nucleosídeos/farmacologia , Antineoplásicos/farmacologia , Antivirais/farmacologia , Testes de Sensibilidade Microbiana/métodos , Mutagênese/fisiologia , Estavudina/análogos & derivados , Estavudina/farmacologia
20.
Talanta ; 233: 122548, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215051

RESUMO

The functionalized non-conjugated organic network modified silica microspheres are proposed as the stationary phase of liquid chromatography, which can effectively avoid some defects of organic framework materials in liquid chromatography. Due to the co-existing of pyridine ring, carbonyl group, amide group and triazine ring in the non-conjugated flexible organic network on the silica surface, the developed mixed-mode stationary phase exhibits multiple interactions between the stationary phase and the analytes during the separation process. A variety of nucleoside bases, organic acids, antibiotics, pesticides, alkylbenzenes, polycyclic aromatic hydrocarbons and sulfonamides achieved ideal resolution and flexible selectivity in separation. Compared with the commercial chromatographic columns under their optimized chromatographic conditions, it shows better performance for the separation of complex analytes. The influence of chromatographic conditions on retention behavior indicates that the column's multiple retention mechanisms make it suitable for mixed-mode liquid chromatography. The stationary phase prepared by the new design strategy also has excellent chromatographic reproducibility, repeatability and stability with the intraday RSD of 0.09%-0.12% (n = 10) and the interday RSD of 0.37%-1.64% (n = 5) for the retention time. The separation results of actual samples also prove its potential in the analysis of complex samples. In short, we designed and prepared the non-conjugated flexible network modified silica stationary phase material for liquid chromatography that is different from organic framework materials. Its excellent separation ability shows that we have successfully reported a new kind of liquid chromatography packing with functional design and facile preparation method.


Assuntos
Nucleosídeos , Dióxido de Silício , Cromatografia Líquida , Interações Hidrofóbicas e Hidrofílicas , Reprodutibilidade dos Testes
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