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1.
Nucleic Acids Res ; 52(16): 9397-9406, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39077944

RESUMO

G-quadruplex (G4) structures play integral roles in modulating biological functions and can be regulated by small molecules. The MYC gene is critical during tumor initiation and malignant progression, in which G4 acts as an important modulation motif. Herein, we reported the MYC promoter G4 recognized by a platinum(II) compound Pt-phen. Two Pt-phen-MYC G4 complex structures in 5 mM K+ were determined by NMR. The Pt-phen first strongly binds the 3'-end of MYC G4 to form a 1:1 3'-end binding complex and then binds 5'-end to form a 2:1 complex with more Pt-phen. In the complexes, the Pt-phen molecules are well-defined and stack over four bases at the G-tetrad for a highly extensive π-π interaction, with the Pt atom aligning with the center of the G-tetrad. The flanking residues were observed to rearrange and cover on top of Pt-phen to stabilize the whole complex. We further demonstrated that Pt-phen targets G4 DNA in living cells and represses MYC gene expression in cancer cells. Our work elucidated the structural basis of ligand binding to MYC promoter G4. The platinum compound bound G4 includes multiple complexes formation, providing insights into the design of metal ligands targeting oncogene G4 DNA.


Assuntos
Quadruplex G , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc , Quadruplex G/efeitos dos fármacos , Humanos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/química , DNA/química , DNA/metabolismo , Compostos de Platina/química , Genes myc , Platina/química
2.
BMC Genomics ; 25(1): 398, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654150

RESUMO

Pinellia ternata (Thunb.) Briet., a valuable herb native to China, is susceptible to the "sprout tumble" phenomenon because of high temperatures, resulting in a significant yield reduction. However, the molecular regulatory mechanisms underlying the response of P. ternata to heat stress are not well understood. In this study, we integrated transcriptome and miRNAome sequencing to identify heat-response genes, microRNAs (miRNAs), and key miRNA-target pairs in P. ternata that differed between heat-stress and room-temperature conditions. Transcriptome analysis revealed extensive reprogramming of 4,960 genes across various categories, predominantly associated with cellular and metabolic processes, responses to stimuli, biological regulation, cell parts, organelles, membranes, and catalytic and binding activities. miRNAome sequencing identified 1,597 known/conserved miRNAs that were differentially expressed between the two test conditions. According to the analysis, genes and miRNAs associated with the regulation of transcription, DNA template, transcription factor activity, and sequence-specific DNA binding pathways may play a major role in the resistance to heat stress in P. ternata. Integrated analysis of the transcriptome and miRNAome expression data revealed 41 high-confidence miRNA-mRNA pairs, forming 25 modules. MYB-like proteins and calcium-responsive transcription coactivators may play an integral role in heat-stress resistance in P. ternata. Additionally, the candidate genes and miRNAs were subjected to quantitative real-time polymerase chain reaction to validate their expression patterns. These results offer a foundation for future studies exploring the mechanisms and critical genes involved in heat-stress resistance in P. ternata.


Assuntos
Resposta ao Choque Térmico , MicroRNAs , Pinellia , Plântula , Transcriptoma , Pinellia/genética , Pinellia/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Resposta ao Choque Térmico/genética , Plântula/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas
3.
Hum Reprod ; 39(2): 310-325, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38011909

RESUMO

STUDY QUESTION: What is the mechanism behind cryoinjury in human sperm, particularly concerning the interplay between reactive oxygen species (ROS) and autophagy, and how does it subsequently affect sperm fate? SUMMARY ANSWER: The freeze-thaw operation induces oxidative stress by generating abundant ROS, which impairs sperm motility and activates autophagy, ultimately guiding the sperm toward programmed cell death such as apoptosis and necrosis, as well as triggering premature capacitation. WHAT IS KNOWN ALREADY: Both ROS-induced oxidative stress and autophagy are thought to exert an influence on the quality of frozen-thawed sperm. STUDY DESIGN, SIZE, DURATION: Overall, 84 semen specimens were collected from young healthy fertile males, with careful quality evaluation. The specimens were split into three groups to investigate the ROS-induced cryoinjury: normal control without any treatment, sperm treated with 0.5 mM hydrogen peroxide (H2O2) for 1 h, and sperm thawed following cryopreservation. Samples from 48 individuals underwent computer-assisted human sperm analysis (CASA) to evaluate sperm quality in response to the treatments. Semen samples from three donors were analyzed for changes in the sperm proteome after H2O2 treatment, and another set of samples from three donors were analyzed for changes following the freeze-thaw process. The other 30 samples were used for fluorescence-staining and western blotting. PARTICIPANTS/MATERIALS, SETTING, METHODS: Sperm motility parameters, including progressive motility (PR %) and total motility (PR + NP %), were evaluated using the CASA system on a minimum of 200 spermatozoa. The proteomic profiles were determined with label-free mass spectrometry (MS/MS) and protein identification was performed via ion search against the NCBI human database. Subsequently, comprehensive bioinformatics was applied to detect significant proteomic changes and functional enrichment. Fluorescence-staining and western blot analyses were also conducted to confirm the proteomic changes on selected key proteins. The ROS level was measured using 2',7'-dichlorodihydrofluorescein diacetate labeling and the abundance of bioactive mitochondria was determined by evaluating the inner mitochondrial membrane potential (MMP) level. Molecular behaviors of sequestosome-1 (p62 or SQSTM1) and microtubule-associated proteins 1A/1B light chain 3 (LC3) were monitored to evaluate the state of apoptosis in human sperm. Fluorescent probes oxazole yellow (YO-PRO-1) and propidium iodide (PI) were utilized to monitor programmed cell death, namely apoptosis and necrosis. Additionally, gradient concentrations of antioxidant coenzyme Q10 (CoQ10) were introduced to suppress ROS impacts on sperm. MAIN RESULTS AND THE ROLE OF CHANCE: The CASA analysis revealed a significant decrease in sperm motility for both the H2O2-treatment and freeze-thaw groups. Fluorescence staining showed that high ROS levels were produced in the treated sperm and the MMPs were largely reduced. The introduction of CoQ10 at concentrations of 20 and 30 µM resulted in a significant rescue of progressive motility (P < 0.05). The result suggested that excessive ROS could be the major cause of sperm motility impairment, likely by damaging mitochondrial energy generation. Autophagy was significantly activated in sperm when they were under oxidative stress, as evidenced by the upregulation of p62 and the increased conversion of LC3 as well as the upregulation of several autophagy-related proteins, such as charged multivesicular body protein 2a, mitochondrial import receptor subunit TOM22 homolog, and WD repeat domain phosphoinositide-interacting protein 2. Additionally, fluorescent staining indicated the occurrence of apoptosis and necrosis in both H2O2-treated sperm and post-thaw sperm. The cell death process can be suppressed when CoQ10 is introduced, which consolidates the view that ROS could be the major contributor to sperm cryoinjury. The freeze-thaw process could also initiate sperm premature capacitation, demonstrated by the prominent increase in tyrosine phosphorylated proteins, verified with anti-phosphotyrosine antibody and immunofluorescence assays. The upregulation of capacitation-related proteins, such as hyaluronidase 3 and Folate receptor alpha, supported this finding. LARGE SCALE DATA: The data underlying this article are available in the article and its online supplementary material. LIMITATIONS, REASONS FOR CAUTION: The semen samples were obtained exclusively from young, healthy, and fertile males with progressive motility exceeding 60%, which might overemphasize the positive effects while possibly neglecting the negative impacts of cryoinjury. Additionally, the H2O2 treatment conditions in this study may not precisely mimic the oxidative stress experienced by sperm after thawing from cryopreservation, potentially resulting in the omission of certain molecular alterations. WIDER IMPLICATIONS OF THE FINDINGS: This study provides substantial proteomic data for a comprehensive and deeper understanding of the impact of cryopreservation on sperm quality. It will facilitate the design of optimal protocols for utilizing cryopreserved sperm to improve applications, such as ART, and help resolve various adverse situations caused by chemotherapy, radiotherapy, and surgery. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from the Major Innovation Project of Research Institute of National Health Commission (#2022GJZD01-3) and the National Key R&D Program of China (#2018YFC1003600). All authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Preservação do Sêmen , Sêmen , Masculino , Humanos , Espécies Reativas de Oxigênio/metabolismo , Sêmen/metabolismo , Motilidade dos Espermatozoides , Peróxido de Hidrogênio , Proteômica , Espectrometria de Massas em Tandem , Espermatozoides/metabolismo , Estresse Oxidativo , Criopreservação/métodos , Preservação do Sêmen/efeitos adversos , Preservação do Sêmen/métodos , Necrose/metabolismo
4.
Nucleic Acids Res ; 50(14): 7816-7828, 2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35766415

RESUMO

G-quadruplex (G4) transitions play integral roles in regulating biological functions and can be modified by ligands. However, little is known about G4 transitions. Herein, we reveal distinct pathways of a platinum(II) compound Pt-phen converting parallel-stranded MYC G4 to a hybrid-type structure. Three NMR structures, 1:1 5'-end binding, 1:1 3'-end binding and 2:1 Pt-phen-MYC G4 complexes, were determined by NMR. We find that Pt-phen drives G4 transition at a low ratio. Under physiological 100 mM K+ conditions, a significant stable hydrogen-bonded T:T:A triad is formed at 3'-end of hybrid-type Myc1234, and consequently, Pt-phen first binds the 5'-end to form a 1:1 5'-end binding complex and then disrupts the 3' T:T:A triad and binds 3'-end to form a 2:1 complex with more Pt-phen. Remarkably, the G4 transition pathway is different in 5 mM K+ with Pt-phen first binding the 3'-end and then the 5'-end. 'Edgewise-loop and flanking/ligand/G-tetrad' sandwich structure formation and terminal T:T:A triad stabilization play decisive roles in advancing and altering transition pathways. Our work is the first to elucidate the molecular structures of G4 transitions driven by a small molecule. The ligand-driven G4 transition is a dynamic process that includes a quick G4 transition and multiple complexes formation.


Assuntos
Quadruplex G , Compostos de Platina , Ligantes , Espectroscopia de Ressonância Magnética , Estrutura Molecular
5.
Zhongguo Zhong Yao Za Zhi ; 49(8): 2128-2137, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812228

RESUMO

The rhizosphere is an important place for material exchange between medicinal plants and soil. Root exudates are the medium of material and signal exchange between plants and soil and are the key factors in the regulation of rhizosphere microecology. Rhizosphere microorganisms are an important part of the rhizosphere microecology of medicinal plants, and the interaction between root exudates and rhizosphere microorganisms has an important influence on the growth and quality formation of medicinal plants. Rational utilization of the interaction between root exudates and rhizosphere microorganisms of medicinal plants is one of the important ways to ensure the healthy growth of medicinal plants and promote the development of ecological planting of Chinese medicinal materials. In the paper, the research status of root exudates and rhizosphere microorganisms of medicinal plants in recent years was summarized. The interaction mechanism between root exudates and rhizosphere microorganisms of medicinal plants, as well as the influence of rhizosphere microorganisms on the growth of medicinal plants, were analyzed. In addition, the advantages and promoting effects of intercropping ecological planting mode on rhizosphere microecology of medicinal plants and quality improvement of Chinese medicinal materials were explained, providing a good basis for the study of the interaction among medicinal plants, microorganisms, and soil. Furthermore, it could produce important theoretical and practical significance for the ecological planting and sustainable utilization of medicinal plants.


Assuntos
Raízes de Plantas , Plantas Medicinais , Rizosfera , Microbiologia do Solo , Plantas Medicinais/metabolismo , Plantas Medicinais/microbiologia , Plantas Medicinais/química , Plantas Medicinais/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Bactérias/metabolismo , Bactérias/classificação , Exsudatos de Plantas/metabolismo , Exsudatos de Plantas/química
6.
Plant J ; 111(6): 1660-1675, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35861696

RESUMO

Maize (Zea mays) is an important cereal crop worldwide. However, its yield and quality are adversely affected by salt stress resulting from soil hypersalinity. Exploring the regulatory mechanisms of stress responses is of vital importance to increase maize seed production. In the present study, we screened ethyl methanesulfonate-induced maize mutants and identified a salt-tolerant mutant. A single base was mutated in ZmWRKY20, leading to the formation of a truncated protein variant. A detailed phenotypic analysis revealed that this mutant had significantly higher resistance to wilting and lower reactive oxygen species levels than the inbred line B73. ZmWRKY20 showed transcriptional activity in yeast and specifically bound W-boxes according to the results of our yeast one-hybrid, electrophoretic mobility shift, and dual-luciferase assays. Overexpression of ZmWRKY20 decreased salt tolerance in maize. Transcriptome profiling revealed that ZmWRKY20 overexpression extensively reprogrammed genes involved in regulating defense and oxidation-reduction responses. The results substantiate that ZmWRKY20 is directly targeted to the basic leucine zipper (bZIP) motif in the transcription factor ZmbZIP111. It was also verified that ZmWRKY20 interacts with ZmWRKY115 and both proteins act jointly to enhance ZmbZIP111 repression. The results indicate that the ZmWRKY20 and ZmWRKY115 transcription factors interact in the nucleus, leading to repression of ZmbZIP111 expression by directly binding its promoter, and increase the sensitivity of maize seedlings to salt stress. The current study improves our understanding of the complicated responses of maize to salt stress.


Assuntos
Tolerância ao Sal , Zea mays , Metanossulfonato de Etila/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/genética , Tolerância ao Sal/genética , Solo , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zea mays/metabolismo
7.
Inorg Chem ; 62(16): 6255-6262, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37026758

RESUMO

An aqueous stable europium-based metal-organic framework with properties of ratiometric fluorescence sensing, namely, {[(CH3)2NH2][Eu(TCPB)(H2O)2]·DMF}n (Eu-MOF; H4TCPB = 1,2,4,5-tetrakis(4-carboxyphenyl)-benzene), was synthesized under solvothermal conditions and structurally characterized. Crystal structure analysis shows that Eu-MOF is a three-dimensional porous crystal, in which the EuIII ion is an eight-coordinate square inverse prism with eight oxygen atoms. Fluorescence measurements show that Eu-MOF exhibits characteristic emission of the EuIII ion and ligand. Eu-MOF displays good selectivity and sensitivity as a ratiometric fluorescence sensor for phosphate anions with a low detection limit in Tris-HCl buffer solution. Furthermore, Eu-MOF also has a good ability to identify salicylaldehyde through fluorescence quenching with a detection limit of 0.095 ppm. Therefore, it is an excellent fluorescent sensing material for phosphate and organic salicylaldehyde.

8.
Inorg Chem ; 62(51): 21322-21328, 2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38071665

RESUMO

Lanthanide-based metal-organic frameworks show good potential for applications due to their unique structures and functional properties. A highly thermally and acid-base stable Eu-MOF was synthesized by a solvothermal method with the molecular formula {[(CH3)2NH2]2[Eu2(NDDP)2(H2O)2]·H2O}n (Eu-MOF, H4NDDP = 5,5'-(naphthalene-2,6-diyl)diisophthalic acid). Eu-MOF takes a three-dimensional (4,4,8)-connected topology. The water molecules involved in the coordination, free water molecules, and [(CH3)2NH2]+ cations in the pore can be used as proton carriers. The proton conductivity attains 1.25 × 10-4 S cm-1 at room temperature and 2.42 × 10-3 S cm-1 at 70 °C and 98% relative humidity. Combined with the dual-emission properties from the ligands and Eu(III) ions enables Eu-MOF to be used as a ratiometric fluorescent sensor for phosphate efficiently and rapidly, with a limit of detection of 0.12 µM in the Tris-HCl buffer solution. These results provide a new approach for the construction of MOFs with high proton conductivity and a ratiometric fluorescence response.

9.
Sensors (Basel) ; 23(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36679560

RESUMO

The rapid development of AIOT-related technologies has revolutionized various industries. The advantage of such real-time sensing, low costs, small sizes, and easy deployment makes extensive use of wireless sensor networks in various fields. However, due to the wireless transmission of data, and limited built-in power supply, controlling energy consumption and making the application of the sensor network more efficient is still an urgent problem to be solved in practice. In this study, we construct this problem as a tree structure wireless sensor network mathematical model, which mainly considers the QoS and fairness requirements. This study determines the probability of sensor activity, transmission distance, and transmission of the packet size, and thereby minimizes energy consumption. The Lagrangian Relaxation method is used to find the optimal solution with the lowest energy consumption while maintaining the network's transmission efficiency. The experimental results confirm that the decision-making speed and energy consumption can be effectively improved.


Assuntos
Redes de Comunicação de Computadores , Tecnologia sem Fio , Simulação por Computador , Algoritmos , Modelos Teóricos
10.
Int J Mol Sci ; 24(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37511363

RESUMO

Using petiole material as explants and directly inducing the formation of microtubers without going through the callus stage is an essential way to rapidly expand scarce medical plants such as Pinellia ternata. However, the early molecular mechanism underlying the formation of the microtuber is largely elusive. Here, we conducted cytology and dynamic transcriptome analyses of inchoate microtubers in Pinellia explants and identified 1092 differentially expressed genes after their cultivation in vitro for 0, 5, and 15 days. Compared with 0 day, the number and size of the microtuber cells were larger at 5 and 15 days of culture. Detailed categorization revealed that the differentially expressed genes were mainly related to responses to stimulus, biological regulation, organelles, membranes, transcription factor activity, and protein binding. Further analysis revealed that the microtuber at different incubation days exhibited quite a difference in both hormone signaling pathway transduction and the regulation pattern of transcription factors. Therefore, this study contributes to a better understanding of the early molecular regulation during the formation of the microtuber and provides new insights for the study of the rapid expansion of P. ternata and other medical plants.


Assuntos
Pinellia , Pinellia/genética , Perfilação da Expressão Gênica , Hormônios/metabolismo , Expressão Gênica
11.
Acta Cardiol Sin ; 39(4): 628-642, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37456949

RESUMO

Background: Studies on disease burden in Taiwan are lacking. We aimed to quantify the burden of cardiovascular disease (CVD) attributable to high body mass index (BMI) in Taiwan. Methods: Using a comparative risk assessment approach from the Global Burden of Disease study, we estimated the population attributable fraction (PAF), attributable CVD burden, and disability-adjusted life years (DALYs) according to sex, age, and area of residence in Taiwan. The BMI distribution for the population was obtained from the National Health Interview Survey in 2013. CVD was defined as an ischemic heart disease or stroke. Results: The attributable PAF for CVD from high BMI was 18.0% (19.6% in men and 15.6% in women), and it was highest (42.7%) in those aged 25-30 years. Adults aged 60-65 years had the highest absolute DALYs (11,546). The average relative age-standardized attributable burden was 314 DALYs per 100,000 person-years, and it was highest in those aged 75-80 years (1,407 DALYs per 100,000 person-years). Those living in Taitung County had the highest PAF of 21.9% and the highest age-standardized attributable burden (412 DALYs). Conclusions: In Taiwan, an 18% reduction in CVDs could be achieved if obesity/overweight was prevented. Prevention was most effective in early adulthood. The absolute CVD burden from obesity/overweight was highest in middle-aged men, and the relative burden was highest in older adults. Resource allocation in targeted populations and specific areas to eliminate CVD and health inequities is urgently required.

12.
Molecules ; 27(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35566188

RESUMO

Protein hydrolysates from various sources, including tuna cooking juice, soy protein isolate, sodium caseinate, wheat gluten and skin gelatin from porcine, tilapia, halibut and milkfish were analyzed to screen their antiproliferative activities against the human oral squamous carcinoma cell line, HSC-3. The soy protein isolate was selected for further investigations based on its hydrolysates with bromelain (SB) and thermolysin (ST), showing the greatest inhibition of cell growth. The SB and ST hydrolysates showed antiproliferative activities up to 35.45-76.39% against HSC-3 cells at 72 h, and their IC50 values were 0.74 and 0.60 mg/mL, respectively. SB and ST induced cell cycle arrest in the S phase through a pathway independent of p21 and p27 protein expression. Further, ST induced the apoptosis of HSC-3 cells by downregulating expression of Bcl-2, PARP, caspase 3 and caspase 9, but an upregulating expression of p53 and cleaved caspase 3. Unlike ST, SB may induce necrosis on HSC-3 cells. Thus, soybean hydrolysates may be a good source for providing antiproliferative peptides against HSC-3, while SB and ST may have the potential to be developed as functional foods.


Assuntos
Neoplasias Bucais , Proteínas de Soja , Animais , Apoptose , Caspase 3/metabolismo , Ciclo Celular , Pontos de Checagem do Ciclo Celular , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Bucais/metabolismo , Proteínas de Soja/farmacologia , Suínos
13.
Zhonghua Nan Ke Xue ; 27(6): 542-546, 2021 Jun.
Artigo em Zh | MEDLINE | ID: mdl-34914296

RESUMO

Extracellular vesicles are cell-to-cell communication tools that play important roles in sperm maturation, motility, and fertilization. Epididymosomes provide proteins, lipids, and genetic materials to sperm as the latter go through the epididymis, not only promoting sperm maturation, but also influencing sperm and offspring phenotypes at the epigenetic level. After ejaculation, prostasomes fuse with sperm, leading to changes in the composition of the sperm plasma membrane and the contents of sperm, which maintains the stability of the sperm plasma membrane and increases sperm motility as well. Uterosomes can enhance sperm capacitation and acrosome reaction. Oviductosomes participate in sperm capacitation and motility, provide non-coding RNA to sperm, and influence the development of embryos. However, studies on extracellular vesicles and spermatozoa are mostly based on animal experiments, and their applicability to humans remains to be further explored.


Assuntos
Vesículas Extracelulares , Motilidade dos Espermatozoides , Animais , Humanos , Masculino , Capacitação Espermática , Maturação do Esperma , Espermatozoides
14.
Indian J Microbiol ; 61(2): 195-202, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33927460

RESUMO

Biphenanthrene compound, 4, 8, 4', 8'-tetramethoxy (1, 1'-biphenanthrene)-2, 7, 2', 7'-tetrol (LF05), recently isolated from fibrous roots of Bletilla striata, exhibits antibacterial activity against several Gram-positive bacteria. In this study, we investigated the antibacterial properties, potential mode of action and cytotoxicity. Minimum inhibitory concentrations (MICs) tests showed LF05 was active against all tested Gram-positive strains, including methicillin-resistant Staphylococcus aureus (MRSA) and staphylococcal clinical isolates. Minimum bactericidal concentration (MBC) tests demonstrated LF05 was bactericidal against S. aureus ATCC 29213 and Bacillus subtilis 168 whereas bacteriostatic against S. aureus ATCC 43300, WX 0002, and other strains of S. aureus. Time-kill assays further confirmed these observations. The flow cytometric assay indicated that LF05 damaged the cell membrane of S. aureus ATCC 29213 and B. subtilis 168. Consistent with this finding, 4 × MIC of LF05 caused release of ATP in B. subtilis 168 within 10 min. Checkerboard test demonstrated LF05 exhibited additive effect when combined with vancomycin, erythromycin and berberine. The addition of rat plasma or bovine serum albumin to bacterial cultures caused significantly loss in antibacterial activity of LF05. Interestingly, LF05 was highly toxic to several tumor cells. Results of these studies indicate that LF05 is bactericidal against some Gram-positive bacteria and acts as a membrane structure disruptor. The application of biphenanthrene in the treatment of S. aureus infection, especially local infection, deserves further study.

15.
Angew Chem Int Ed Engl ; 60(28): 15340-15343, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33899272

RESUMO

G-quadruplexes (G4s) are prevalent in oncogenes and are potential antitumor drug targets. However, binding selectivity of compounds to G4s still faces challenges. Herein, we report a platinum(II) complex (Pt1), whose affinity to G4-DNA is activated by adaptive binding and selectivity controlled by binding kinetics. The resolved structure of Pt1/VEGF-G4 (a promoter G4) shows that Pt1 matches 3'-G-tetrad of VEGF-G4 through Cl- -dissociation and loop rearrangement of VEGF-G4. Binding rate constants are determined by coordination bond breakage/formation, correlating fully with affinities. The selective rate-determining binding step, Cl- -dissociation upon G4-binding, is 2-3 orders of magnitude higher than dsDNA. Pt1 potently targets G4 in living cells, effectively represses VEGF expression, and inhibits vascular growth in zebrafish. We show adaptive G4-binding activation and controlled by kinetics, providing a complementary design principle for compounds targeting G4 or similar biomolecules.


Assuntos
Antineoplásicos/farmacologia , Quadruplex G/efeitos dos fármacos , Compostos Organoplatínicos/farmacologia , Antineoplásicos/química , Sítios de Ligação/efeitos dos fármacos , Células HeLa , Humanos , Cinética , Estrutura Molecular , Compostos Organoplatínicos/química
16.
Plant Cell Rep ; 39(1): 135-148, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31659429

RESUMO

KEY MESSAGE: Overexpression in rice of the isolated salt-responsive WRKY114 gene from maize resulted in decreases in both salt-stress tolerance and abscisic acid sensitivity by regulating stress- and abscisic acid-related gene expression. WRKYs are an important family of transcription factors that widely participate in plant development, defense regulation and stress responses. In this research, WRKY114 encoding a WRKY transcription factor was cloned from maize (Zea mays L.). ZmWRKY114 expression was down-regulated by salt stress but up-regulated by abscisic acid (ABA) treatments. ZmWRKY114 is a nuclear protein with no transcriptional activation ability in yeast. A yeast one-hybrid experiment confirmed that ZmWRKY114 possesses an ability to specifically bind to W-boxes. The heterologous overexpression of ZmWRKY114 in rice enhanced the salt-stress sensitivity as indicated by the transgenic plants having reduced heights, root lengths and survival rates under salt-stress conditions. In addition, transgenic plants also retained lower proline contents, but greater malondialdehyde contents and relative electrical leakage levels. Additionally, ZmWRKY114-overexpressing plants showed less sensitivity to ABA during the early seedling growth stage. Further analyses indicated that transgenic rice accumulated higher levels of ABA than wild-type plants under salt-stress conditions. Transcriptome and quantitative real-time PCR analyses indicated that a few regulatory genes, which play vital roles in controlling plant stress responses and/or the ABA signaling pathway, were affected by ZmWRKY114 overexpression when rice was treated with NaCl. Thus, ZmWRKY114 may function as a negative factor that participates in salt-stress responses through an ABA-mediated pathway.


Assuntos
Oryza/genética , Proteínas de Plantas/metabolismo , Tolerância ao Sal , Fatores de Transcrição/metabolismo , Zea mays/genética , Ácido Abscísico/farmacologia , Núcleo Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Oryza/efeitos dos fármacos , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Salino/genética , Tolerância ao Sal/genética , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Fatores de Transcrição/genética , Zea mays/metabolismo
17.
Lipids Health Dis ; 19(1): 115, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32471496

RESUMO

BACKGROUND: Aortic stenosis is a common heart valvular disease whose pathological processes include an inflammatory reaction and lipid accumulation. However, its detailed pathogenesis is yet to be completely elucidated. Therefore, it is of great significance to further explore the molecular mechanisms of aortic stenosis. METHODS: Four datasets were downloaded from the Gene Expression Omnibus (GEO) database. Firstly, the differently expressed genes (DEGs) were screened between control and aortic stenosis samples. Secondly, weighted gene co-expression network analysis (WGCNA) was performed to find the highly relevant gene modules. Enrichment analysis and protein-protein interaction (PPI) networking were also performed, then Cytoscape was used to identify hub genes. Finally, the six participants (3 control participants and 3 patients with aortic stenosis) were recruited at the Tianjin Chest Hospital. In order to verify the expression level of USP14, several molecular experiments were performed, including hematoxylin-eosin (HE) staining, immunohistochemistry, immunofluorescence technology, real time-quantitative polymerase chain reaction (RT-qPCR), and western blotting. RESULTS: A total of 9636 DEGs were found between the control and aortic stenosis samples. The DEGs were mainly enriched in the autophagy-animal, cellular lipid catabolic process, apoptosis, and glycoside metabolic process categories. Eleven hub genes were identified via four different algorithms. Following verification of the patient samples, Ubiquitin-specific protease 14 (USP14) was found to be displayed at higher levels in the aortic stenosis samples. CONCLUSION: USP14 might be involved in the occurrence and development of aortic stenosis, so it would be a molecular target for early diagnosis and specific treatment of aortic stenosis. There is a significant association between the high expression of USP14 and aortic stenosis, indicating that this gene may be a genetic risk factor for aortic stenosis.


Assuntos
Estenose da Valva Aórtica/diagnóstico , Biomarcadores/metabolismo , Ubiquitina Tiolesterase/genética , Proteases Específicas de Ubiquitina/genética , Estenose da Valva Aórtica/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/genética , Humanos , Mapas de Interação de Proteínas/genética , Ubiquitina/genética , Ubiquitina Tiolesterase/isolamento & purificação , Proteases Específicas de Ubiquitina/isolamento & purificação
18.
Sensors (Basel) ; 20(20)2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33080918

RESUMO

Due to the popularity of indoor positioning technology, indoor navigation applications have been deployed in large buildings, such as hospitals, airports, and train stations, to guide visitors to their destinations. A commonly-used user interface, shown on smartphones, is a 2D floor map with a route to the destination. The navigation instructions, such as turn left, turn right, and go straight, pop up on the screen when users come to an intersection. However, owing to the restrictions of a 2D navigation map, users may face mental pressure and get confused while they are making a connection between the real environment and the 2D navigation map before moving forward. For this reason, we developed ARBIN, an augmented reality-based navigation system, which posts navigation instructions on the screen of real-world environments for ease of use. Thus, there is no need for users to make a connection between the navigation instructions and the real-world environment. In order to evaluate the applicability of ARBIN, a series of experiments were conducted in the outpatient area of the National Taiwan University Hospital YunLin Branch, which is nearly 1800 m2, with 35 destinations and points of interests, such as a cardiovascular clinic, x-ray examination room, pharmacy, and so on. Four different types of smartphone were adopted for evaluation. Our results show that ARBIN can achieve 3 to 5 m accuracy, and provide users with correct instructions on their way to the destinations. ARBIN proved to be a practical solution for indoor navigation, especially for large buildings.

19.
Zhonghua Nan Ke Xue ; 26(3): 219-222, 2020 Mar.
Artigo em Zh | MEDLINE | ID: mdl-33346960

RESUMO

The novel coronavirus disease 2019 (COVID-19) broke out in December 2019 and has been rapidly escalating throughout the world. Clinical findings show that the patients with either symptomatic or asymptomatic COVID-19 can be a potential source of infection. Although respiratory droplets and close contact are considered to be the main routes of transmission, there is the possibility of aerosol transmission in a relatively closed environment. The nucleic acid of the novel coronavirus can be detected in nasopharyngeal swabs, sputum and other lower respiratory tract secretions, blood, feces, urine and so on, but whether it exists in the semen has not been confirmed. It is reported that the novel coronavirus may affect the testis that highly expresses angiotensin-converting enzyme 2 (ACE2) and theoretically the semen is a possible carrier of the virus considering the fact that it is discharged from the same channel as the urine. Andrology laboratorians are exposed to most of the specimens above, including semen, and some open operations in the laboratory increase the risk of aerosol generation. Therefore, corresponding protective procedures are necessitated in andrology laboratories to reduce the risk of infection during the outbreak of COVID-19. Based on the knowledge and experience available as regards the pandemic and the characteristics of the work in the andrology laboratory, we summarize some biosafety points for andrology laboratorians to attend to during the outbreak of COVID-19.


Assuntos
Andrologia/organização & administração , COVID-19 , Contenção de Riscos Biológicos , Laboratórios/organização & administração , Humanos , Masculino
20.
Zhongguo Zhong Yao Za Zhi ; 45(17): 4230-4237, 2020 Sep.
Artigo em Zh | MEDLINE | ID: mdl-33164408

RESUMO

A method based on high performance liquid chromatography(HPLC) was developed for simultaneous content determination of 14 components in rhubarb charcoal. After 18 batches of raw rhubarb materials were heated at different temperatures and time points, the contents of 14 components(5 categories) were determined, including gallic acid, 5-hydroxymethylfurfural(5-HMF), 5 kinds of free anthraquinone, 5 kinds of bound anthraquinone and 2 kinds of sennosides. In the analysis of sample color characteristics combined with principal component analysis(PCA), it was found that 18 batches of samples can be grouped into five categories, with the traditional traits "black charred on the surface, dark brown inside" as the standard. Samples of category A, B, C and D were "less" carbonized, and category E samples were carbonized "moderately or a little bit excessively". The corresponding components sennoside and combined anthraquinone showed a one-way decreasing pattern, and the contents of free anthraquinone, gallic acid and 5-HMF showed an increasing pattern before decreasing. The results showed that the contents of free anthraquinone and gallic acid in the samples were larger than those in raw materials while the contents of glycosides and combined anthraquinone were lower than those in raw materials when the samples were "less" "moderately" or "a little bit excessively" carbonized. The two change modes of the component contents of the studied samples have good robustness, and have a reference value for more comprehensive evaluation and control of different heating conditions from the perspective of chemical characterization on the color and content of rhubarb charcoal and the change mode of the content of other carbon medicines.


Assuntos
Medicamentos de Ervas Chinesas , Rheum , Antraquinonas , Carvão Vegetal , Cromatografia Líquida de Alta Pressão , Calefação
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