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1.
BMC Genomics ; 25(1): 602, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886667

RESUMO

BACKGROUND: Spermatogenesis is a highly regulated and complex process in which DNA methylation plays a crucial role. This study aimed to explore the differential methylation profiles in sperm DNA between patients with asthenospermia (AS) and healthy controls (HCs), those with oligoasthenospermia (OAS) and HCs, and patients with AS and those with OAS. RESULTS: Semen samples and clinical data were collected from five patients with AS, five patients with OAS, and six age-matched HCs. Reduced representation bisulfite sequencing (RRBS) was performed to identify differentially methylated regions (DMRs) in sperm cells among the different types of patients and HCs. A total of 6520, 28,019, and 16,432 DMRs were detected between AS and HC, OAS and HC, and AS and OAS groups, respectively. These DMRs were predominantly located within gene bodies and mapped to 2868, 9296, and 9090 genes in the respective groups. Of note, 12, 9, and 8 DMRs in each group were closely associated with spermatogenesis and male infertility. Furthermore, BDNF, SMARCB1, PIK3CA, and DDX27; RBMX and SPATA17; ASZ1, CDH1, and CHDH were identified as strong differentially methylated candidate genes in each group, respectively. Meanwhile, the GO analysis of DMR-associated genes in the AS vs. HC groups revealed that protein binding, cytoplasm, and transcription (DNA-templated) were the most enriched terms in the biological process (BP), cellular component (CC), and molecular function (MF), respectively. Likewise, in both the OAS vs. HC and AS vs. OAS groups, GO analysis revealed protein binding, nucleus, and transcription (DNA-templated) as the most enriched terms in BP, CC, and MF, respectively. Finally, the KEGG analysis of DMR-annotated genes and these genes at promoters suggested that metabolic pathways were the most significantly associated across all three groups. CONCLUSIONS: The current study results revealed distinctive sperm DNA methylation patterns in the AS vs. HC and OAS vs. HC groups, particularly between patients with AS and those with OAS. The identification of key genes associated with spermatogenesis and male infertility in addition to the differentially enriched metabolic pathways may contribute to uncovering the potential pathogenesis in different types of abnormal sperm parameters.


Assuntos
Astenozoospermia , Metilação de DNA , Oligospermia , Humanos , Masculino , Astenozoospermia/genética , Adulto , Oligospermia/genética , Espermatozoides/metabolismo , Espermatogênese/genética , Estudos de Casos e Controles , Epigênese Genética
2.
BMC Genomics ; 25(1): 325, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561670

RESUMO

BACKGROUND: Non-coding RNA is a key epigenetic regulation factor during skeletal muscle development and postnatal growth, and miR-542-3p was reported to be conserved and highly expressed in the skeletal muscle among different species. However, its exact functions in the proliferation of muscle stem cells and myogenesis remain to be determined. METHODS: Transfection of proliferative and differentiated C2C12 cells used miR-542-3p mimic and inhibitor. RT-qPCR, EdU staining, immunofluorescence staining, cell counting kit 8 (CCK-8), and Western blot were used to evaluate the proliferation and myogenic differentiation caused by miR-542-3p. The dual luciferase reporter analysis and rescued experiment of the target gene were used to reveal the molecular mechanism. RESULTS: The data shows overexpression of miR-542-3p downregulation of mRNA and protein levels of proliferation marker genes, reduction of EdU+ cells, and cellular vitality. Additionally, knocking it down promoted the aforementioned phenotypes. For differentiation, the miR-542-3p gain-of-function reduced both mRNA and protein levels of myogenic genes, including MYOG, MYOD1, et al. Furthermore, immunofluorescence staining immunized by MYHC antibody showed that the myotube number, fluorescence intensity, differentiation index, and myotube fusion index all decreased in the miR-542-3p mimic group, compared with the control group. Conversely, these phenotypes exhibited an increased trend in the miR-542-3p inhibitor group. Mechanistically, phosphatase and tensin homolog (Pten) was identified as the bona fide target gene of miR-542-3p by dual luciferase reporter gene assay, si-Pten combined with miR-542-3p inhibitor treatments totally rescued the promotion of proliferation by loss-function of miR-542-3p. CONCLUSIONS: This study indicates that miR-542-3p inhibits the proliferation and differentiation of myoblast and Pten is a dependent target gene of miR-542-3p in myoblast proliferation, but not in differentiation.


Assuntos
MicroRNAs , MicroRNAs/genética , MicroRNAs/metabolismo , Epigênese Genética , Proliferação de Células/genética , Diferenciação Celular/genética , RNA Mensageiro/metabolismo , Desenvolvimento Muscular/genética , Mioblastos , Luciferases/genética , Luciferases/metabolismo
3.
Macromol Rapid Commun ; 45(6): e2300631, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38158931

RESUMO

A water-soluble polymeric pyrene-based polythioacetal (PTA-Py) with thioacetal units in the main chain is simply synthesized by direct polycondensation of 3, 6-dioxa-1, 8-octanedithiol, 1-pyrene formaldehyde, and mPEG2k-SH. The probe PTA-Py shows a good fluorescence response to Hg2+ ions due to the Hg2+-promoted deprotection reaction of thioacetal groups to regenerate the original 1-pyrene formaldehyde compound. After adding Hg2+ to the PTA-Py solution, the fluorescence intensity (FI) gradually increases with increasing concentrations of Hg2+. Compared with other metal ions, the probe exhibits high sensitivity, good selectivity, and rapid response to Hg2+. The low detection limits are 12.3 nm in ethanol-PBS buffer and 13.3 nm in water, respectively. The results imply that the simply synthesized water-soluble polymeric probe had potential applications in the rapid detection of Hg2+ ions in aqueous solutions. Moreover, the polymeric PTA-Py shows high sensitivity for CH3Hg+ with detection limits of 26.5 nm in ethanol/PBS buffer. In addition, PTA-Py can efficiently detect Hg2+ ions in HeLa cells. The results demonstrate that a valuable method is developed for biocompatible polymeric sensors for Hg2+ ions in biological and environmental samples.


Assuntos
Mercúrio , Humanos , Corantes Fluorescentes , Células HeLa , Água , Pirenos , Polímeros , Íons , Espectrometria de Fluorescência , Etanol , Formaldeído
4.
Bioorg Chem ; 144: 107163, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38306825

RESUMO

The development of effective antibacterial drugs to combat bacterial infections, particularly the biofilm-related infections, remains a challenge. There are two important features of bacterial biofilms, which are well-known critical factors causing biofilms hard-to-treat in clinical, including the dense and impermeable extracellular polymeric substances (EPS) and the metabolically repressed dormant and persistent bacterial population embedded. These characteristics largely increase the difficulty for regular antibiotic treatment due to insufficient penetration into EPS. In addition, the dormant bacteria are insensitive to the growth-inhibiting mechanism of traditional antibiotics. Herein, we explore the potential of a series of new oligopyridinium-based oligomers bearing a multi-biomacromolecule targeting function as the potent bacterial biofilm eradication agent. These oligomers were rationally designed to be "charge-on-backbone" that can offer a special alternating amphiphilicity. This novel and unique feature endows high affinity to bacterial membrane lipids, DNAs as well as proteins. Such a broad multi-targeting nature of molecules not only enables its penetration into EPS, but also plays vital roles in the bactericidal mechanism of action that is highly effective against dormant and persistent bacteria. Our in vitro, ex vivo, and in vivo studies demonstrated that OPc3, one of the most effective derivatives, was able to offer excellent antibacterial potency against a variety of bacteria and effectively eliminate biofilms in zebrafish models and mouse wound biofilm infection models.


Assuntos
Infecções Bacterianas , Peixe-Zebra , Animais , Camundongos , Biofilmes , Bactérias , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia
5.
J Am Chem Soc ; 145(42): 23372-23384, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37838963

RESUMO

Intracellular bacterial pathogens, such as Staphylococcus aureus, that may hide in intracellular vacuoles represent the most significant manifestation of bacterial persistence. They are critically associated with chronic infections and antibiotic resistance, as conventional antibiotics are ineffective against such intracellular persisters due to permeability issues and mechanistic reasons. Direct subcellular targeting of S. aureus vacuoles suggests an explicit opportunity for the eradication of these persisters, but a comprehensive understanding of the chemical biology nature and significance of precise S. aureus vacuole targeting remains limited. Here, we report an oligoguanidine-based peptidomimetic that effectively targets and eradicates intracellular S. aureus persisters in the phagolysosome lumen, and this oligomer was utilized to reveal the mechanistic insights linking precise targeting to intracellular antimicrobial efficacy. The oligomer has high cellular uptake via a receptor-mediated endocytosis pathway and colocalizes with S. aureus persisters in phagolysosomes as a result of endosome-lysosome interconversion and lysosome-phagosome fusion. Moreover, the observation of a bacterium's altered susceptibility to the oligomer following a modification in its intracellular localization offers direct evidence of the critical importance of precise intracellular targeting. In addition, eradication of intracellular S. aureus persisters was achieved by the oligomer's membrane/DNA dual-targeting mechanism of action; therefore, its effectiveness is not hampered by the hibernation state of the persisters. Such precise subcellular targeting of S. aureus vacuoles also increases the agent's biocompatibility by minimizing its interaction with other organelles, endowing excellent in vivo bacterial targeting and therapeutic efficacy in animal models.


Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Bactérias , Biologia , Testes de Sensibilidade Microbiana
6.
Environ Sci Technol ; 57(43): 16500-16511, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37844026

RESUMO

Nitrogen-containing organic compounds (NOCs), a type of important reactive-nitrogen species, are abundant in organic aerosols in haze events observed in Northern China. However, due to the complex nature of NOCs, the sources, formation, and influencing factors are still ambiguous. Here, the molecular composition of organic matters (OMs) in hourly PM2.5 samples collected during a haze event in Northern China was characterized using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). We found that CHON compounds (formulas containing C, H, O, and N atoms) dominated the OM fractions during the haze and showed high chemodiversity and transformability. Relying on the newly developed revised-workflow and oxidation-hydrolyzation knowledge for CHON compounds, 64% of the major aromatic CHON compounds (>80%) could be derived from the oxidization or hydrolyzation processes. Results from FT-ICR MS data analysis further showed that the aerosol liquid water (ALW)-involved aqueous-phase reactions are important for the molecular distribution of aromatic-CHON compounds besides the coal combustion, and the ALW-involved aromatic-CHON compound formation during daytime and nighttime was different. Our results improve the understanding of molecular composition, sources, and potential formation of CHON compounds, which can help to advance the understanding for the formation, evolution, and control of haze.


Assuntos
Poluentes Atmosféricos , Compostos de Nitrogênio , Compostos de Nitrogênio/análise , Água , Espectrometria de Massas/métodos , Compostos Orgânicos/análise , Nitrogênio/análise , China , Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental
7.
Environ Sci Technol ; 57(49): 20726-20735, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38035574

RESUMO

δ18O is widely used to track nitrate (NO3-) formation but overlooks NO3 radical reactions with hydrocarbons (HCs), particularly in heavily emitting hazes. This study introduces high-time resolution Δ17O-NO3- as a powerful tool to quantify NO3- formation during five hazes in three cities. Results show significant differences between Δ17O-NO3- and δ18O-NO3- in identifying NO3- formation. δ18O-NO3- results suggested N2O5 hydrolysis (62.0-88.4%) as the major pathway of NO3- formation, while Δ17O-NO3- shows the NO3- formation contributions of NO2 + OH (17.7-66.3%), NO3 + HC (10.8-49.6%), and N2O5 hydrolysis (22.9-33.3%), revealing significant NO3 + HC contribution (41.7-56%) under severe pollution. Furthermore, NO3- formation varies with temperatures, NOx oxidation rate (NOR), and pollution levels. Higher NO2 + OH contribution and lower NO3 + HC contribution were observed at higher temperatures, except for low NOR haze where higher NO2 + OH contributions were observed at low temperatures (T ← 10 °C). This emphasizes the significance of NO2 + OH in emission-dominated haze. Contributions of NO2 + OH and NO3 + HC relate to NOR as positive (fP1 = 3.0*NOR2 - 2.4*NOR + 0.8) and negative (fP2 = -2.3*NOR2 + 1.8*NOR) quadratic functions, respectively, with min/max values at NOR = 0.4. At mild pollution, NO2 + OH (58.1 ± 22.2%) dominated NO3- formation, shifting to NO3 + HC (35.5 ± 16.3%) during severe pollution. Additionally, high-time resolution Δ17O-NO3- reveals that morning-evening rush hours and high temperatures at noon promote the contributions of NO3 + HC and NO2 + OH, respectively. Our results suggested that the differences in the NO3- pathway are attributed to temperatures, NOR, and pollution levels. Furthermore, high-time resolution Δ17O-NO3- is vital for quantifying NO3 + HC contribution during severe hazes.


Assuntos
Monitoramento Ambiental , Dióxido de Nitrogênio , Nitratos/análise , Cidades , Isótopos de Nitrogênio/análise , China
8.
Acta Biochim Biophys Sin (Shanghai) ; 55(3): 472-483, 2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-36988349

RESUMO

The proliferation and differentiation of myoblasts are considered the key biological processes in muscle development and muscle-related diseases, in which the miRNAs involved remain incompletely understood. Previous research reported that miR-424(322)-5p is highly expressed in mouse skeletal muscle. Therefore, C2C12 cells are used as a model to clarify the effect of miR-424(322)-5p on the proliferation and differentiation of myoblasts. The data show that miR-424(322)-5p exhibits a decreasing trend upon myogenic differentiation. Overexpression of miR-424(322)-5p inhibits the proliferation of myoblasts, manifested by downregulation of proliferation marker genes ( CCNB1, CCND2, and CDK4), decreased percentage of EdU + cells, and reduced cell viability. In contrast, these phenotypes are promoted in myoblasts treated with an inhibitor of miR-424(322)-5p. Interestingly, its gain of function inhibits the expression of myogenic regulators, including MyoD, MyoG, MyHC, and Myf5. Additionally, immunofluorescence staining of MyHC and MyoD shows that overexpression of miR-424(322)-5p reduces the number of myotubes and decreases the myotube fusion index. Consistently, inhibition of its function mediated by an inhibitor promotes the expressions of myogenic markers and myotube fusion. Mechanistically, gene prediction and dual-luciferase reporter experiments confirm that enhancer of zeste homolog 1 ( Ezh1) is one of the targets of miR-424(322)-5p. Furthermore, knockdown of Ezh1 inhibits the proliferation and differentiation of myoblasts. Compared with NC and inhibitor treatment, inhibitor+si- EZH1 treatment rescues the phenotypes of proliferation and differentiation mediated by the miR-424(322)-5p inhibitor. Taken together, these data indicate that miR-424(322)-5p targets Ezh1 to negatively regulate the proliferation and differentiation of myoblasts.


Assuntos
MicroRNAs , Animais , Camundongos , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/genética , MicroRNAs/metabolismo , Mioblastos/metabolismo
9.
Anim Biotechnol ; 34(7): 2846-2854, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36125800

RESUMO

Tribbles homolog 2 (TRIB2) plays an important role in the follicular development of female mammals. However, its expression and function in the yak (Bos grunniens) are still unclear. In this study, we predicted the molecular characteristics of TRIB2, and revealed its expression pattern in yak (Bos grunniens) tissues and ovarian granulosa cells. We cloned the full length of the yak TRIB2 gene obtained by RT-PCR was 1368 bp and the coding sequence (CDS) was 624 bp, encoding 207 amino acids (AA). Homology analysis showed that the yak TRIB2 is highly conserved among species. TRIB2 was detected to be extensively expressed in seven tissues of the yak liver, spleen, lung, kidney, ovary, oviduct and uterus by qPCR. The expression of TRIB2 mRNA in the ovary during gestation was significantly lower than that in the non-pregnant (p < 0.05). At each stage of follicle development, the TRIB2 mRNA in granulosa cells showed a significant upward trend with the development of follicles. The expression of TRIB2 gradually decreased with the increase of the culture time of the granulosa cells in vitro. In conclusion, these results suggest that TRIB2 may play an important role in the follicular development of yaks.


Assuntos
Ovário , Útero , Bovinos/genética , Feminino , Animais , Sequência de Aminoácidos , Ovário/metabolismo , Útero/metabolismo , Células da Granulosa/metabolismo , RNA Mensageiro/genética , Mamíferos/genética , Mamíferos/metabolismo
10.
J Am Chem Soc ; 144(23): 10622-10639, 2022 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-35657057

RESUMO

Gram-negative bacteria, especially the ones with multidrug resistance, post dire challenges to antibiotic treatments due to the presence of the outer membrane (OM), which blocks the entry of many antibiotics. Current solutions for such permeability issues, namely lipophilic-cationic derivatization of antibiotics and sensitization with membrane-active agents, cannot effectively potentiate the large, globular, and hydrophilic antibiotics such as vancomycin, due to ineffective disruption of the OM. Here, we present our solution for high-degree OM binding of vancomycin via a hybrid "derivatization-for-sensitization" approach, which features a combination of LPS-targeting lipo-cationic modifications on vancomycin and OM disruption activity from a sensitizing adjuvant. 106- to 107-fold potentiation of vancomycin and 20-fold increase of the sensitizer's effectiveness were achieved with a combination of a vancomycin derivative and its sensitizer. Such potentiation is the result of direct membrane lysis through cooperative membrane binding for the sensitizer-antibiotic complex, which strongly promotes the uptake of vancomycin and adds to the extensive antiresistance effectiveness. The potential of such derivatization-for-sensitization approach was also supported by the combination's potent in vivo antimicrobial efficacy in mouse model studies, and the expanded application of such strategy on other antibiotics and sensitizer structures.


Assuntos
Bactérias Gram-Negativas , Vancomicina , Animais , Antibacterianos/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Vancomicina/farmacologia
11.
Anal Biochem ; 655: 114824, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35944695

RESUMO

Food-borne diseases caused by pathogenic bacteria are one of the serious factors affecting human health. However, the most commonly used detection methods for pathogenic bacteria not only require expensive instruments, but also take a long time due to the complicated and cumbersome detection process. Therefore, the development of a fast, simple, and low-cost detection method for pathogenic bacteria is crucial for food safety and human health. In this work, based on the high binding ability of antimicrobial peptide (AMP) and polymyxin B (PMB) to bacteria, combined with magnetic separation technology, a new enzyme-free colorimetric strategy was constructed to achieve visual detection of Gram-negative bacteria in complex samples. The sensor system was divided into the following two parts: a colorimetric signal amplification nanoprobe, which was modified with AMP to enable effective binding of the colorimetric probe to the surface of bacteria, and a PMB-modified magnetic nanobead (MNB), which was used as the capture and enrichment unit of Gram-negative bacteria, as a result of which PMB could effectively distinguish Gram-negative bacteria from Gram-positive bacteria. Under optimized conditions, the detection limit of the method for Gram-negative bacteria (e.g. E. coli (G-)) was as low as 10 CFU/mL, and it was successfully applied to complex real samples. In addition, the developed colorimetric sensor offered advantages, such as fast response, less time consumption, high sensitivity, and low cost. It can be expected to become a new diagnostic tool for on-site detection of pathogenic bacteria in remote areas.


Assuntos
Colorimetria , Escherichia coli , Humanos , Bactérias , Colorimetria/métodos , Bactérias Gram-Negativas , Fenômenos Magnéticos
12.
Molecules ; 27(18)2022 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-36144830

RESUMO

We used next-generation QTAIM (NG-QTAIM) to explain the cis-effect for two families of molecules: C2X2 (X = H, F, Cl) and N2X2 (X = H, F, Cl). We explained why the cis-effect is the exception rather than the rule. This was undertaken by tracking the motion of the bond critical point (BCP) of the stress tensor trajectories Tσ(s) used to sample the Uσ-space cis- and trans-characteristics. The Tσ(s) were constructed by subjecting the C1-C2 BCP and N1-N2 BCP to torsions ± θ and summing all possible Tσ(s) from the bonding environment. During this process, care was taken to fully account for multi-reference effects. We associated bond-bending and bond-twisting components of the Tσ(s) with cis- and trans-characteristics, respectively, based on the relative ease of motion of the electronic charge density ρ(rb). Qualitative agreement is found with existing experimental data and predictions are made where experimental data is not available.


Assuntos
Teoria Quântica , Ligação de Hidrogênio
13.
Nat Chem Biol ; 15(9): 889-899, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31427817

RESUMO

Mycobacterium tuberculosis (Mtb) is the world's most deadly pathogen. Unlike less virulent mycobacteria, Mtb produces 1-tuberculosinyladenosine (1-TbAd), an unusual terpene nucleoside of unknown function. In the present study 1-TbAd has been shown to be a naturally evolved phagolysosome disruptor. 1-TbAd is highly prevalent among patient-derived Mtb strains, where it is among the most abundant lipids produced. Synthesis of TbAd analogs and their testing in cells demonstrate that their biological action is dependent on lipid linkage to the 1-position of adenosine, which creates a strong conjugate base. Furthermore, C20 lipid moieties confer passage through membranes. 1-TbAd selectively accumulates in acidic compartments, where it neutralizes the pH and swells lysosomes, obliterating their multilamellar structure. During macrophage infection, a 1-TbAd biosynthesis gene (Rv3378c) confers marked phagosomal swelling and intraphagosomal inclusions, demonstrating an essential role in regulating the Mtb cellular microenvironment. Although macrophages kill intracellular bacteria through phagosome acidification, Mtb coats itself abundantly with antacid.


Assuntos
Antiácidos/metabolismo , Lipídeos/biossíntese , Lipídeos/química , Mycobacterium tuberculosis/metabolismo , Fagossomos/metabolismo , Animais , Regulação Bacteriana da Expressão Gênica , Humanos , Concentração de Íons de Hidrogênio , Lisossomos , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Mycobacterium kansasii/genética , Prevalência
14.
Physiol Mol Biol Plants ; 27(1): 69-80, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33627963

RESUMO

Pear (Pyrus spp.) belongs to the genus Pyrus, in the family Rosaceae. Some varieties of pear fruit exhibit bulged surface, which seriously affects the quality and commodity value of the pear fruit. In this study, we performed anatomical, physiological, and transcriptomic analysis to explore the mechanism of paclobutrazol (PBZ) on the bulged surface of pear fruit. The vascular bundles of flesh were more evenly distributed, and the fruit cells were more compactly arranged and smaller in size treated with PBZ. However, the auxin (IAA) content of flesh was decreased in the treated group. Furthermore, the GO and KEGG analysis of differentially expressed genes (DEGs) showed that auxin, phenylpropanoid metabolic pathways, and transcriptional factor genes were significantly enriched on the relieved bulged surface of pear fruit. And it was analyzed that some genes contained auxin responded cis-elements from the selected DEGs in the promoter region. We conclude that PBZ plays a negative role in cell division, cell elongation, and vascular bundle development on the bulged surface of pear fruit through the involvement of auxin-related genes. This study will provide a theoretical basis for the regulation of the bulged surface of pear fruit by a growth retardant agent. SUPPLEMENTARY INFORMATION: The online version of this article (10.1007/s12298-021-00929-z) contains supplementary material, which is available to authorized users.

15.
Eur J Clin Microbiol Infect Dis ; 39(9): 1771-1779, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32242313

RESUMO

Pentamidine sensitizes FDA-approved antibiotics to combat Gram-negative pathogens. We screened 1374 FDA-approved non-antibiotics for their ability to be sensitized by pentamidine against Escherichia coli. We identified mitomycin C and mefloquine as potent hits effective against multiple drug-resistant, Gram-negative bacteria. Killing kinetics and an in vivo model with Caenorhabditis elegans (C. elegans) revealed that such combinations produced synergy against colistin-resistant Enterobacter cloacae (E. cloacae). These findings suggest combinations of FDA-approved non-antibiotics, and pentamidine can be repurposed into new antimicrobial agents.


Assuntos
Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Pentamidina/farmacologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Caenorhabditis elegans/efeitos dos fármacos , Reposicionamento de Medicamentos , Farmacorresistência Bacteriana Múltipla , Sinergismo Farmacológico , Quimioterapia Combinada , Enterobacter cloacae/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Modelos Animais , Pentamidina/administração & dosagem , Pentamidina/uso terapêutico , Estados Unidos , United States Food and Drug Administration
16.
Physiol Mol Biol Plants ; 26(10): 2085-2094, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33088052

RESUMO

OVATE family proteins (OFPs) are the plant-specific transcription factors, and have significant functions in regulating plant growth, development and resistance. The OFP genes have been investigated in several plants, but they still lack a systematic analysis of OFP genes in Chinese pear and some other five Rosaceae genomes. Here, 28 PbrOFPs were identified within Chinese pear and compared them with those of other five Rosaceae genomes. Evolutionary tree revealed that all OFP genes from six Rosaceae genomes were divided into eight groups. Seventeen conserved microsynteny regions were detected in Chinese pear genome, suggested that these PbrOFP genes might be considered to have originated from the large-scale duplication events., indicating these PbrOFP genes might contain specialized regulatory mechanisms in these tissues, such as flower, ovary and fruit. Remarkably, two PbrOFP genes (Pbr010426.1 and Pbr010427.1) were up-regulated under Venturia nashicola treatment, and five PbrOFP genes were up-regulated under PEG treatment, suggesting that these genes might play crucial roles in defence to environmental stresses. Our data presented a systematic analysis and might aid in the selection of appropriate PbrOFPs for further functional studies in Chinese pear, especially in response to the mechanism of biotic and abiotic stresses.

17.
Biochem Biophys Res Commun ; 512(3): 517-523, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30904161

RESUMO

Invasive aspergillosis (IA) is a life-threatening disease impacting immunocompromised individuals. Standard treatments of IA, including polyenes and azoles, suffer from high toxicity and emerging resistance, leading to the need to develop new antifungal agents with novel mechanisms of action. Ergosterol biosynthesis is a classic target for antifungals, and squalene synthase (SQS) catalyzes the first committed step in ergosterol biosynthesis in Aspergillus spp. making SQS of interest in the context of antifungal development. Here, we cloned, expressed, purified and characterized SQS from the pathogen Aspergillus flavus (AfSQS), confirming that it produced squalene. To identify potential leads targeting AfSQS, we tested known squalene synthase inhibitors, zaragozic acid and the phosphonosulfonate BPH-652, finding that they were potent inhibitors. We then screened a library of 744 compounds from the National Cancer Institute (NCI) Diversity Set V for inhibition activity. 20 hits were identified and IC50 values were determined using dose-response curves. 14 compounds that interfered with the assay were excluded and the remaining 6 compounds were analyzed for drug-likeness, resulting in one compound, celastrol, which had an AfSQS IC50 value of 830 nM. Enzyme inhibition kinetics revealed that celastrol binds to AfSQS in a noncompetitive manner, but did not bind covalently. Since celastrol is also known to inhibit growth of the highly virulent Aspergillus fumigatus by inhibiting flavin-dependent monooxygenase siderophore A (SidA, under iron starvation conditions), it may be a promising multi-target lead for antifungal development.


Assuntos
Antifúngicos/farmacologia , Aspergillus flavus/enzimologia , Inibidores Enzimáticos/farmacologia , Farnesil-Difosfato Farnesiltransferase/antagonistas & inibidores , Farnesil-Difosfato Farnesiltransferase/metabolismo , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Aspergillus flavus/genética , Aspergillus flavus/metabolismo , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Clonagem Molecular , Farnesil-Difosfato Farnesiltransferase/genética , Humanos , Modelos Moleculares , Terapia de Alvo Molecular , Triterpenos Pentacíclicos , Ácidos Tricarboxílicos/farmacologia , Triterpenos/farmacologia
18.
Cancer Cell Int ; 19: 199, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31384174

RESUMO

BACKGROUND: Ovarian cancer is often accompanied by the production of ascites, and patients with repeated ascites are associated with chemotherapy resistance. The previous study confirmed that the ovarian cancer patients who developed ascites after chemotherapy had elevated autophagy levels in the ascites and precipitated cells, which was positively correlated with MDR1 expression in the blood of patients. METHODS: In order to explore the correlation between autophagy and chemoresistant, we searched TCGA and GEO database to analyze the correlation between LC3B and MDR1, and identified the targeting miRNA of LC3B. It was verified by dual luciferase that miR-204 can target LC3B. The ovarian cancer cell line and the BALB/c nude mice tumor-bearing model were selected for in vitro and in vivo verification. In vitro studies confirmed that ovarian cancer cells were more sensitive to cisplatin by inhibiting LC3B. RESULTS: Overexpression of miR-204 reduced the expression of LC3B, Atg7, and MDR1, and promoted apoptosis. In vivo studies have also confirmed that reducing the level of autophagy in ovarian cancer cells increases the sensitivity to cisplatin. CONCLUSIONS: It suggests that miR-204 can be used as a tumor suppressor gene and LC3B expression level can be used as a potential molecular marker to guide the diagnosis and treatment of patients with ovarian cancer.

19.
Asia Pac J Clin Nutr ; 28(4): 783-792, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31826376

RESUMO

BACKGROUND AND OBJECTIVES: Citrus fruit are suggested to be associated with reduced risk of nasopharyngeal carcinoma (NPC), but findings from epidemiologic studies have been inconsistent. We aimed to synthesize the association by conducting a meta-analysis of existing evidence. METHODS AND STUDY DESIGN: Databases including Medline, EMBASE, Web of science, and the Cochrane Library were searched for eligible studies up to March 2019 using a series comprehensive searching terms. The adjusted odds ratios (ORs) of citrus fruit intake with NPC risk from each study were extracted to calculate a pooled association estimate with its 95% confidence interval (CI). RESULTS: Nine studies totaling 3304 cases and 3850 controls were included in this analysis. Citrus fruit intake was significantly associated with reduced risk of NPC (OR: 0.72, 95% CI 0.58-0.91, p=0.005). In addition, this association tended to be stronger in Chinese (OR: 0.67, 95% CI 0.54-0.84, p<0.001). Dose-response analysis using cubic splines showed the risk of NPC decreased by 21% for citrus fruit intake of 4 times/week (OR: 0.79, 95% CI 0.66-0.94). CONCLUSIONS: Consumption of citrus fruit was associated with a significantly reduced risk of NPC, especially in Chinese.


Assuntos
Citrus , Dieta , Frutas , Carcinoma Nasofaríngeo/prevenção & controle , Humanos , Fatores de Risco
20.
J Sci Food Agric ; 99(12): 5491-5498, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31095729

RESUMO

BACKGROUND: During planting, storage and transportation of maize excessive amounts of pesticides are used to ensure production, resulting in pesticide residues on the maize that can threaten human health. Plasma, compared with other technologies, has been widely regarded as a green, safe and promising technology for surface decontamination to ensure maize safety and quality. RESULTS: The aim of this study is to discuss plasma effects on the degradation of chlorpyrifos and carbaryl on maize surface and the changes of treated maize quality. Results achieved the largest degradation efficiency of chlorpyrifos and carbaryl, up to 91.5% and 73.1%, respectively. The physical changes of maize were observed by scanning electron microscopy (SEM), showing a decrease in contact angle, an increase in surface free energy and polar component, leading to improved hydrophilicity of the treated maize. There was no significant change of vitamin B2 content of maize. A significant increase of acid value and decrease of moisture content and starch content were observed within acceptable limits. CONCLUSION: It is reasonable to believe that argon plasma treatment enhances the edible safety of maize while maintaining maize quality. © 2019 Society of Chemical Industry.


Assuntos
Argônio/farmacologia , Resíduos de Praguicidas/química , Gases em Plasma/farmacologia , Zea mays/química , Zea mays/efeitos dos fármacos , Argônio/química , Carbaril/química , Clorpirifos/química , Contaminação de Alimentos/análise , Cinética , Controle de Qualidade , Riboflavina/análise , Amido/análise
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