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1.
Plant Cell Environ ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39267528

RESUMO

The isolated microspores can be reprogrammed towards embryogenesis via stress treatment during in vitro culture, and produce (doubled) haploid plants as a breeding source of new genetic variability. However, the mechanism underlying the cell fate transition from gametogenesis to embryogenesis remains largely unknown. Here, we report that autophagy plays a key role in cell fate transition for microspore embryogenesis (referred to as androgenesis) in Nicotiana tabacum. Immunofluorescence and transmission electronic microscopy detection unveiled that autophagy was triggered in microspores following exposure to inductive stress, and a transient wave of the numerous autophagy-related genes (ATGs) expression occurred before the initiation of microspore embryogenesis. Suppression or promotion of the original autophagy levels could inhibit microspore embryogenesis, indicating that stress-induced autophagic homeostasis is essential for cell fate transition. Furthermore, quantitative proteomics analysis revealed that autophagy might be involved in lignin biosynthesis and chromatin decondensation for promoting reprogramming for androgenesis initiation. Altogether, we reveal an essential role of autophagy in the microspore cell fate transition and androgenesis initiation, providing novel insight for understanding this critical developmental process.

2.
Physiol Plant ; 176(5): e14476, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39262125

RESUMO

Drought stress is a predominant abiotic factor leading to decreased alfalfa yield. Genomic ploidy differences contribute to varying adaptation mechanisms of different alfalfa cultivars to drought conditions. This study employed a multi-omics approach to characterize the molecular basis of drought tolerance in a tetraploid variant of alfalfa (Medicago sativa, Xinjiang-Daye). Under drought treatment, a total of 4446 genes, 859 proteins, and 524 metabolites showed significant differences in abundance. Integrative analysis of the multi-omics data revealed that regulatory modules involved in flavonoid biosynthesis, plant hormone signalling transduction, linoleic acid metabolism, and amino acid biosynthesis play crucial roles in alfalfa adaptation to drought stress. The severity of drought led to the substantial accumulation of flavonoids, plant hormones, free fatty acids, amino acids, and their derivatives in the leaves. Genes such as PAL, 4CL, CHI, CHS, PP2C, ARF_3, and AHP_4 play pivotal regulatory roles in flavonoid biosynthesis and hormone signalling pathways. Differential expression of the LOX gene emerged as a key factor in the elevated levels of free fatty acids. Upregulation of P5CS_1 and GOT1/2 contributed significantly to the accumulation of Pro and Phe contents. ERF19 emerged as a principal positive regulator governing the synthesis of the aforementioned compounds. Furthermore, observations suggest that Xinjiang-Daye alfalfa may exhibit widespread post-transcriptional regulatory mechanisms in adapting to drought stress. The study findings unveil the critical mechanisms by which Xinjiang-Daye alfalfa adapts to drought stress, offering novel insights for the improvement of alfalfa germplasm resources.


Assuntos
Adaptação Fisiológica , Secas , Regulação da Expressão Gênica de Plantas , Medicago sativa , Tetraploidia , Medicago sativa/genética , Medicago sativa/fisiologia , Medicago sativa/metabolismo , Adaptação Fisiológica/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Flavonoides/metabolismo , Flavonoides/biossíntese , Reguladores de Crescimento de Plantas/metabolismo , Multiômica
3.
BMC Surg ; 24(1): 11, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172798

RESUMO

BACKGROUND: In various surgical specialties, preoperative surgical warm-up has been demonstrated to affect a surgeon's performance and the perioperative outcomes for patients. However, the influence of warm-up activities on video-assisted thoracoscopic surgery lobectomy (VATSL) remains largely unexplored. This study aims to investigate the potential effects of preoperative surgical warm-up on VATSL. METHODS: A cohort of 364 patients diagnosed with lung cancer through pathology and undergoing VATSL at the Thoracic Surgery Department of Xuzhou Medical University from January 2018 to September 2022 were included. Patients were categorized into two groups: the warm-up group, comprising 172 patients undergoing their first VATSL of the day, and the warm-up effect group, consisting of 192 patients undergoing their second VATSL on the same day. Propensity score matching was employed to compare operation times and postoperative complications between the two groups, resulting in 159 matched cases in each group. RESULTS: There were no statistically significant differences in operation time (154.5 ± 54.9 vs. 147.2 ± 54.4 min, p = 0.239) and postoperative complications (including pulmonary infection, atelectasis, long-term pulmonary air leakage requiring incision suture in the operating room, and postoperative pleural effusion) (14:22 cases, p = 0.157) between the warm-up and warm-up effect groups. CONCLUSION: The findings suggest that preoperative surgical warm-up does not significantly affect the perioperative outcomes of VATSL.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Cirurgiões , Humanos , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Cirurgia Torácica Vídeoassistida/métodos , Pneumonectomia/métodos , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
4.
World J Microbiol Biotechnol ; 40(6): 182, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38668902

RESUMO

The effect of barium ions on the biomineralization of calcium and magnesium ions is often overlooked when utilizing microbial-induced carbonate precipitation technology for removing barium, calcium, and magnesium ions from oilfield wastewater. In this study, Bacillus licheniformis was used to bio-precipitate calcium, magnesium, and barium ions. The effects of barium ions on the physiological and biochemical characteristics of bacteria, as well as the components of extracellular polymers and mineral characteristics, were also studied in systems containing coexisting barium, calcium, and magnesium ions. The results show that the increasing concentrations of barium ions decreased pH, carbonic anhydrase activity, and concentrations of bicarbonate and carbonate ions, while it increased the contents of humic acids, proteins, polysaccharides, and DNA in extracellular polymers in the systems containing all three types of ions. With increasing concentrations of barium ions, the content of magnesium within magnesium-rich calcite and the size of minerals precipitated decreased, while the full width at half maximum of magnesium-rich calcite, the content of O-C=O and N-C=O, and the diversity of protein secondary structures in the minerals increased in systems containing all three coexisting ions. Barium ions does inhibit the precipitation of calcium and magnesium ions, but the immobilized bacteria can mitigate the inhibitory effect. The precipitation ratios of calcium, magnesium, and barium ions reached 81-94%, 68-82%, and 90-97%. This research provides insights into the formation of barium-enriched carbonate minerals and offers improvements for treating oilfield wastewater.


Assuntos
Bacillus licheniformis , Bário , Biomineralização , Cálcio , Magnésio , Magnésio/metabolismo , Bacillus licheniformis/metabolismo , Bário/metabolismo , Cálcio/metabolismo , Águas Residuárias/microbiologia , Águas Residuárias/química , Concentração de Íons de Hidrogênio , Íons , Anidrases Carbônicas/metabolismo , Carbonato de Cálcio/metabolismo
5.
Int J Mol Sci ; 24(5)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36902478

RESUMO

As a member of the TRIM (tripartite motif) protein family, TRIM56 can function as an E3 ubiquitin ligase. In addition, TRIM56 has been shown to possess deubiquitinase activity and the ability to bind RNA. This adds to the complexity of the regulatory mechanism of TRIM56. TRIM56 was initially found to be able to regulate the innate immune response. In recent years, its role in direct antiviral and tumor development has also attracted the interest of researchers, but there is no systematic review on TRIM56. Here, we first summarize the structural features and expression of TRIM56. Then, we review the functions of TRIM56 in TLR and cGAS-STING pathways of innate immune response, the mechanisms and structural specificity of TRIM56 against different types of viruses, and the dual roles of TRIM56 in tumorigenesis. Finally, we discuss the future research directions regarding TRIM56.


Assuntos
Carcinogênese , Proteínas com Motivo Tripartido , Vírus , Humanos , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Vírus/metabolismo
6.
Angew Chem Int Ed Engl ; 61(8): e202115800, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-34842317

RESUMO

An ideal cancer treatment should not only destroy primary tumors but also improve the immunogenicity of the tumor microenvironment to achieve a satisfactory anti-tumor immune effect. We designed a carbonic anhydrase IX (CAIX)-anchored rhenium(I) photosensitizer, named CA-Re, that not only performs type-I and type-II photodynamic therapy (PDT) with high efficiency under hypoxia (nanomolar-level phototoxicity), but also evokes gasdermin D (GSDMD) mediated pyroptotic cell death to effectively stimulate tumor immunogenicity. CA-Re could disrupt and self-report the loss of membrane integrity simultaneously. This promoted the maturation and antigen-presenting ability of dendritic cells (DCs), and fully activated T cells dependent adaptive immune response in vivo, eventually eliminating distant tumors at the same time as destroying primary tumors. To the best of our knowledge, CA-Re is the first metal complex-based pyroptosis inducer.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/farmacologia , Complexos de Coordenação/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Animais , Antígenos de Neoplasias/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Morte Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Células Dendríticas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Piroptose/efeitos dos fármacos , Rênio/química , Rênio/farmacologia , Relação Estrutura-Atividade , Linfócitos T/efeitos dos fármacos , Hipóxia Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
7.
Technol Soc ; 66: 101669, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34898759

RESUMO

With the progress of epidemic containment, the Chinese government has relaxed its regulatory policies on street vending, hoping to help people who have lost their livelihoods and to assist in the restoration of social and economic order. In response, Chinese people poured into the stall economy, especially individual peddlers, with great expectations for street vending. Street vending has become a hot topic on Chinese social network sites (SNSs). Based on the push-pull-mooring framework, SNS information overload theory was introduced and combined with the actual situations of street vending in China, and a structural equation model was established to study factors affecting individual Chinese peddlers' intention to engage in street vending and the effects of SNS information overload on these factors. Results revealed that perceived policy benefits, subjective norms, and switching cost perceptions of individual peddlers were positive factors affecting their intention to engage in street vending. SNS information overload positively affected individual peddlers' dissatisfaction with their original business model, anxieties over their livings, perception of policy benefits, and subjective norms but negatively affected individual peddlers' perception of switching costs.

8.
BMC Cardiovasc Disord ; 20(1): 297, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32552856

RESUMO

BACKGROUND: The present study aimed to summarize the clinical application of microincision vein harvesting (MVH) of the great saphenous vein in coronary artery bypass grafting (CABG). METHODS: From July 2014 to October 2017, 160 patients underwent coronary artery bypass grafting. Among them, 80 patients received MVH of the great saphenous vein, and 80 received open venous harvesting (OVH). The results of the sampling operation, complications during hospitalization, and the long-term patency of the great saphenous vein were compared between the two groups. RESULTS: All the patients in both groups received successful operations. The difference in the length of the veins obtained and the injury of the veins was not statistically significant (P > 0.05). The difference in the long-term patency rate of the graft vessels between the two groups was not statistically significant. The in-hospital mortality rate was the same in both groups. The MVH group had noticeable advantages over the OVH group in terms of the vein collection times, the incision length, and the complications experienced when performing the leg incisions (P < 0.01). The time relating to the patients' observed early out-of-bed activity was significantly longer in the MVH group. Furthermore, the patients' hospitalization length was significantly shorter in the MVH group compared to the OVH group (P < 0.05). The MVH group had significant advantages in pain score and patient satisfaction, and this difference was also statistically significant (P < 0.05). CONCLUSIONS: The MVH procedure met the requirements of CABG in vein grafting. When compared with OVH, MVH can significantly reduce leg incision complications and improve patients' overall satisfaction with their hospital experience.


Assuntos
Ponte de Artéria Coronária , Microcirurgia , Veia Safena/transplante , Coleta de Tecidos e Órgãos/métodos , Idoso , Ponte de Artéria Coronária/efeitos adversos , Ponte de Artéria Coronária/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Tempo de Internação , Masculino , Microcirurgia/efeitos adversos , Microcirurgia/mortalidade , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Retrospectivos , Veia Safena/diagnóstico por imagem , Veia Safena/fisiopatologia , Fatores de Tempo , Coleta de Tecidos e Órgãos/efeitos adversos , Coleta de Tecidos e Órgãos/mortalidade , Resultado do Tratamento , Grau de Desobstrução Vascular
9.
J Org Chem ; 84(17): 11306-11315, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31433638

RESUMO

An enantioselective organocatalytic desymmetrization of 2,2-disubstituted cyclopentene-1,3-diones via a formal C(sp2)-H amidation is reported. The reaction was carried out with N-methoxy amide as the nitrogen source and commercially available cinchonidine as the catalyst under mild reaction conditions, releasing methanol as the only byproduct. It provides an efficient way to synthesize enantioenriched chiral cyclopentenyl amines bearing an all-carbon quaternary stereogenic carbon center.

10.
Mikrochim Acta ; 186(10): 668, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31486902

RESUMO

A fluorometric method is described for the determination of ofloxacin (OFL). It is based on the use of the fluorescent intercalator SYBR Green I (SG-I). The OFL-aptamer has G-quadruplex structures and can be recognized by SG-I. It results in strong fluorescence of SG-I. If OFL is present, OFL will bind to its aptamer to form stable complexes. This induces the despiralization of partial dsDNA regions, leads to changes in the structure of the aptamer. Thus, SG-I is released from the OFL-aptamer into solution. Hence, the fluorescence of SG-I drops. Fluorescence decreases linearly in the 1.1 to 200 nM OFL concentration range, and the limit of detection is 0.34 nM. The method shows good selectivity to much interference including analogues, hormones, pesticides. It is also effortless and fast with the times of measurement of <40 min. In addition, good recoveries of 91.3-119.0% were found for tap water, river water and artificial urine spiked with OFL with relative standard deviation (RSD) of ≤11.6%. Graphical abstract A sensitive fluorometric method is developed for ofloxacin (OFL) detection in aqueous samples based on the fluorescence intensity change of SYBR Green I (SG-I) with or without OFL.

11.
Mikrochim Acta ; 185(7): 355, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29971570

RESUMO

A colorimetric method is presented for the determination of the antibiotic ofloxacin (OFL) in aqueous solution. It is based on the use of an aptamer and gold nanoparticles (AuNPs). In the absence of OFL, the AuNPs are wrapped by the aptamer and maintain dispersed even at the high NaCl concentrations. The solution with colloidally dispersed AuNPs remains red and has an absorption peak at 520 nm. In the presence of OFL, it will bind to the aptamer which is then released from the AuNPs. Hence, AuNPs will aggregate in the salt solution, and color gradually turns to blue, with a new absorption peak at 650 nm. This convenient and specific colorimetric assay for OFL has a linear response in the 20 to 400 nM OFL concentration range and a 3.4 nM detection limit. The method has a large application potential for OFL detection in environmental and biological samples. Graphical abstract Schematic of a sensitive and simple colorimetric aptasensor for ofloxacin (OFL) detection in tap water and synthesic urine. The assay is based on the salt-induced aggregation of gold nanoparticles which results in a color change from red to purple.

12.
Anal Chem ; 89(10): 5193-5200, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28418637

RESUMO

Polyethylene glycols (PEGs) are synthetic polymers composed of repeating ethylene oxide subunits. They display excellent biocompatibility and are widely used as pharmaceutical excipients. To fully understand the biological fate of PEGs requires accurate and sensitive analytical methods for their quantitation. Application of conventional liquid chromatography-tandem mass spectrometry (LC-MS/MS) is difficult because PEGs have polydisperse molecular weights (MWs) and tend to produce multicharged ions in-source resulting in innumerable precursor ions. As a result, multiple reaction monitoring (MRM) fails to scan all ion pairs so that information on the fate of unselected ions is missed. This Article addresses this problem by application of liquid chromatography-triple-quadrupole/time-of-flight mass spectrometry (LC-Q-TOF MS) based on the MSALL technique. This technique performs information-independent acquisition by allowing all PEG precursor ions to enter the collision cell (Q2). In-quadrupole collision-induced dissociation (CID) in Q2 then effectively generates several fragments from all PEGs due to the high collision energy (CE). A particular PEG product ion (m/z 133.08592) was found to be common to all linear PEGs and allowed their total quantitation in rat plasma with high sensitivity, excellent linearity and reproducibility. Assay validation showed the method was linear for all linear PEGs over the concentration range 0.05-5.0 µg/mL. The assay was successfully applied to the pharmacokinetic study in rat involving intravenous administration of linear PEG 600, PEG 4000, and PEG 20000. It is anticipated the method will have wide ranging applications and stimulate the development of assays for other pharmaceutical polymers in the future.


Assuntos
Polietilenoglicóis/análise , Espectrometria de Massas em Tandem/métodos , Animais , Cromatografia Líquida de Alta Pressão , Meia-Vida , Limite de Detecção , Masculino , Peso Molecular , Plasma/química , Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , Ratos , Ratos Wistar , Reprodutibilidade dos Testes
13.
Anal Biochem ; 523: 17-23, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28137603

RESUMO

In this paper, we developed a fluorescent aptasensor for 17ß-estradiol (E2) determination in aqueous solution using label-free E2-specific aptamer, gold nanoparticles (AuNPs) and Rhodamine B (RhoB) as sensing probe, fluorescent quencher and fluorescent indicator respectively. In the absence of E2, AuNPs were wrapped by E2 aptamer and maintained dispersed in NaCl solution basically. These dispersed AuNPs could effectively impair the originally high fluorescence of RhoB. Contrarily, in the presence of E2, E2 aptamer could specifically combine with E2 to form E2-aptamer complex, so the AuNPs were released by E2 aptamer and aggregated under the influence of NaCl. The aggregated AuNPs have a weak influence on RhoB fluorescence. Therefore, the E2 concentration can be determined by the change of fluorescence intensity of RhoB. This fluorescent assay has a detection limit as low as 0.48 nM, a linear range from 0.48 to 200 nM, and high selectivity over other disrupting chemicals. It was applied to determine E2 in water samples with recoveries in the range of 94.3-111.7%. The fluorescent aptasensor holds great potential for E2 detection in environmental water samples.


Assuntos
Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Estradiol/análise , Fluorescência , Ouro/química , Nanopartículas Metálicas/química , Rodaminas/química , Corantes Fluorescentes/química , Humanos , Limite de Detecção
14.
Anal Biochem ; 514: 2-7, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27615801

RESUMO

This paper proposes an aptasensor for progesterone (P4) detection in human serum and urine based on the aggregating behavior of gold nanoparticles (AuNPs) controlled by the interactions among P4-binding aptamer, target P4 and cationic surfactant hexadecyltrimethylammonium bromide (CTAB). The aptamer can form an aptamer-P4 complex with P4, leaving CTAB free to aggregate AuNPs in this aptasensor. Thus, the sensing solution will turn from red (520 nm) to blue (650 nm) in the presence of P4 because P4 aptamers are used up firstly owing to the formation of an aptamer-P4 complex, leaving CTAB free to aggregate AuNPs. However, in the absence of P4, CTAB combines with aptamers so that AuNPs still remain dispersed. Therefore, this assay makes it possible to detect P4 not only by absorbance measurement but also through naked eyes. By monitoring the variation of absorbance and color, a CTAB-induced colorimetric assay for P4 detection was established with a detection limit of 0.89 nM. Besides, the absorbance ratio A650/A520 has a linear correlation with the P4 concentration of 0.89-500 nM. Due to the excellent recoveries in serum and urine, this biosensor has great potential with respect to the visual and instrumental detection of P4 in biological fluids.


Assuntos
Técnicas Biossensoriais/instrumentação , Colorimetria/métodos , Progesterona/sangue , Progesterona/urina , Aptâmeros de Nucleotídeos , Técnicas Biossensoriais/métodos , Cetrimônio , Compostos de Cetrimônio/química , Colorimetria/instrumentação , Ouro/química , Humanos , Nanopartículas Metálicas/química , Sensibilidade e Especificidade , Tensoativos/química
15.
Drug Metab Dispos ; 43(10): 1430-40, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26239185

RESUMO

Sulfonation is an important metabolic pathway for hesperetin. However, the mechanisms for the cellular disposition of hesperetin and its sulfate metabolites are not fully established. In this study, disposition of hesperetin via the sulfonation pathway was investigated using human embryonic kidney (HEK) 293 cells overexpressing sulfotransferase 1A3. Two monosulfates, hesperetin-3'-O-sulfate (H-3'-S) and hesperetin-7-O-sulfate (H-7-S), were rapidly generated and excreted into the extracellular compartment upon incubation of the cells with hesperetin. Regiospecific sulfonation of hesperetin by the cell lysate followed the substrate inhibition kinetics (Vmax = 0.66 nmol/min per mg, Km = 12.9 µM, and Ksi= 58.1 µM for H-3'-S; Vmax = 0.29 nmol/min per mg, Km = 14.8 µM, and Ksi= 49.1 µM for H-7-S). The pan-multidrug resistance-associated protein (MRP) inhibitor MK-571 at 20 µM essentially abolished cellular excretion of both H-3'-S and H-7-S (the excretion activities were only 6% of the control), whereas the breast cancer resistance protein-selective inhibitor Ko143 had no effects on sulfate excretion. In addition, knockdown of MRP4 led to a substantial reduction (>47.1%; P < 0.01) in sulfate excretion. Further, H-3'-S and H-7-S were good substrates for transport by MRP4 according to the vesicular transport assay. Moreover, sulfonation of hesperetin and excretion of its metabolites were well characterized by a two-compartment pharmacokinetic model that integrated drug uptake and sulfonation with MRP4-mediated sulfate excretion. In conclusion, the exporter MRP4 controlled efflux transport of hesperetin sulfates in HEK293 cells. Due to significant expression in various organs/tissues (including the liver and kidney), MRP4 should be a determining factor for the elimination and body distribution of hesperetin sulfates.


Assuntos
Arilsulfotransferase/metabolismo , Hesperidina/metabolismo , Fígado/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Sulfatos/metabolismo , Animais , Transporte Biológico/fisiologia , Células HEK293 , Humanos , Ratos
16.
BMC Cancer ; 15: 50, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25885449

RESUMO

BACKGROUND: Drug resistance is a major challenge in cancer therapeutics. Abundant evidence indicates that DNA repair systems are enhanced after repetitive chemotherapeutic treatments, rendering cancers cells drug-resistant. Flap endonuclease 1 (FEN1) plays critical roles in DNA replication and repair and in counteracting replication stress, which is a key mechanism for many chemotherapeutic drugs to kill cancer cells. FEN1 was previously shown to be upregulated in response to DNA damaging agents. However, it is unclear about the transcription factors that regulate FEN1 expression in human cancer. More importantly, it is unknown whether up-regulation of FEN1 has an adverse impact on the prognosis of chemotherapeutic treatments of human cancers. METHODS: To reveal regulation mechanism of FEN1 expression, we search and identify FEN1 transcription factors or repressors and investigate their function on FEN1 expression by using a combination of biochemical, molecular, and cellular approaches. Furthermore, to gain insights into the impact of FEN1 levels on the response of human cancer to therapeutic treatments, we determine FEN1 levels in human breast cancer specimens and correlate them to the response to treatments and the survivorship of corresponding breast cancer patients. RESULTS: We observe that FEN1 is significantly up-regulated upon treatment of chemotherapeutic drugs such as mitomycin C (MMC) and Taxol in breast cancer cells. We identify that the transcription factor/repressor YY1 binds to the FEN1 promoter and suppresses the expression of FEN1 gene. In response to the drug treatments, YY1 is dissociated from the FEN1 promoter region leading over-expression of FEN1. Overexpression of YY1 in the cells results in down-regulation of FEN1 and sensitization of the cancer cells to MMC or taxol. Furthermore, we observe that the level of FEN1 is inversely correlated with cancer drug and radiation resistance and with survivorship in breast cancer patients. CONCLUSION: Altogether, our current data indicate that YY1 is a transcription repressor of FEN1 regulating FEN1 levels in response to DNA damaging agents. FEN1 is up-regulated in human breast cancer and its levels inversely correlated with cancer drug and radiation resistance and with survivorship in breast cancer patients.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Endonucleases Flap/genética , Regulação Neoplásica da Expressão Gênica , Fator de Transcrição YY1/metabolismo , Antineoplásicos/farmacologia , Sequência de Bases , Sítios de Ligação , Neoplasias da Mama/mortalidade , Linhagem Celular , Sequência Conservada , Feminino , Humanos , Estimativa de Kaplan-Meier , Motivos de Nucleotídeos , Prognóstico , Regiões Promotoras Genéticas , Ligação Proteica
17.
J Sep Sci ; 38(8): 1351-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25631297

RESUMO

The pentapeptide thymopentin (Arg-Lys-Asp-Val-Tyr, RKDVY) corresponds to amino acids 32-36 of the 49 amino acid immunomodulatory polypeptide, thymopoietin, whose biological activity is partially reproduced. Thymopentin is widely used in the clinic and represents a promising target for drug design but bioanalytical and pharmacokinetic data are limited due to its enzymatic instability. This paper reports a rapid and sensitive method based on liquid chromatography with tandem mass spectrometry for the determination of thymopentin in beagle dog blood. To inactivate peptidases and stabilize thymopentin, acetonitrile was added to blood samples immediately after collection followed by addition of stable isotope-labeled thymopentin as internal standard and washing with dichloromethane. Chromatography was carried out on an Ascentis Express Peptide ES-C18 column using gradient elution with methanol and aqueous 0.1% formic acid at a flow rate of 0.6 mL/min. Positive electrospray ionization mass spectrometry with selected reaction monitoring achieved linearity in the range of 1.5-800 ng/mL with good accuracy/precision and minimal matrix effects. The method was successfully applied to a pharmacokinetic study in beagle dogs after intravenous administration of 0.2 mg/kg thymopentin.


Assuntos
Cromatografia Líquida , Espectrometria de Massas em Tandem , Timopentina/sangue , Acetonitrilas/química , Animais , Calibragem , Cães , Modelos Lineares , Cloreto de Metileno/química , Peptídeos/química , Controle de Qualidade , Reprodutibilidade dos Testes , Espectrometria de Massas por Ionização por Electrospray
18.
Xenobiotica ; 45(11): 945-53, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26068529

RESUMO

1. UDP-glucuronosyltransferase 1A1 (UGT1A1) plays an irreplaceable role in detoxification of bilirubin and many drugs (e.g., SN-38). Here we aimed to explore the potential of UGT1A1-overexpressing HeLa cells (or HeLa1A1 cells) as a tool to accurately identify UGT1A1 inhibitors. 2. Determination of glucuronidation rates (ß-estradiol and SN-38 as the substrates) was performed using HeLa1A1 cells and uridine diphosphoglucuronic acid (UDPGA)-supplemented cDNA expressed UGT1A1 enzyme (or microsomes). The inhibitory effects (IC50 values) of 20 structurally diverse compounds on the UGT1A1 activity were determined using HeLa1A1 cells and microsomal incubations. 3. In HeLa1A1 cells, the IC50 values for inhibition of ß-estradiol glucuronidation by the tested compounds ranged from 0.33 to 94.6 µM. In the microsomal incubations, the IC50 values ranged from 0.47 to 155 µM. It was found that the IC50 values of all test compounds derived from the cells were well consistent with those from the microsomes (deviated by less than two-fold). Further, the IC50 values from the cells were strongly correlated with those from microsomes (r = 0.944, p < 0.001). Likewise, the IC50 values (0.37-77.3 µM) for inhibition of SN-38 glucuronidation in the cells were close to those (0.42-122 µM) for glucuronidation inhibition in microsomes. A strong correlation was also observed between the two sets of IC50 values (r = 0.978, p < 0.001). 4. In conclusion, UGT1A1-overexpressing HeLa cells were an appropriate tool to accurately depict the inhibition profiles of chemicals against UGT1A1.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Glucuronosiltransferase/antagonistas & inibidores , Glucuronosiltransferase/biossíntese , Microssomos/enzimologia , Glucuronosiltransferase/genética , Células HeLa , Humanos
19.
Biomol Biomed ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38980684

RESUMO

Lupus nephritis (LN) is an autoimmune disease that rapidly progresses as a secondary consequence of systemic lupus erythematosus (SLE) and has a very poor prognosis. Therefore, this study aimed to identify characteristics of immune cell infiltration and investigate potential therapeutic targets using bioinformatics methods and the Murphy Roths Large/lymphoproliferation (MRL/lpr) mouse model. In this study, a total of 2,810 differentially expressed genes (DEGs) were identified, which were primarily enriched in inflammatory and immune regulation pathways. From these DEGs, 226 immune-related genes (IRGs) were also identified. The single-sample gene set enrichment analysis (ssGSEA) revealed that patients with LN had increased infiltration of effector memory CD4+ T cells, effector memory CD8+ T cells, gamma delta T cells, myeloid-derived suppressor cells (MDSC), follicular helper T cells, Th1 cells, and Th2 cells, and this was closely correlated with the DEG-IRGs. Furthermore, the potential therapeutic biomarkers, CD244, S100 calcium binding protein P (S100P), and vascular endothelial growth factor C (VEGFC), were identified by Random Forest Approach (RFA), which were validated in LN mice. These findings provide new evidence and insights for further research on diagnosis and treatment of LN by identifying critical genes and their associations with immune infiltration.

20.
Int Immunopharmacol ; 138: 112566, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38943968

RESUMO

BACKGROUND: T cell infiltration and differentiation play a central part in the development of lupus nephritis (LN). Our prior research has indicated that protein, the primary active component of cordyceps (WCP), a traditional Chinese medicine, possesses properties that can enhance renal fibrosis and provide kidney protection. Nonetheless, the connection between WCP and T cell infiltration and differentiation in LN remains poorly understood. OBJECTIVE: The objective of this research was to assess the immunomodulatory impacts of WCP in LN mice and elucidate the underlying mechanism through in vivo and in vitro investigations. METHODS: To investigate the impact and mechanism of WCP in MRL/lpr lupus-prone mice, WCP (1.5 g/kg/d), Bailing capsules (BC, 0.75 g/kg/d), and saline in equivalent quantities were administered to the mice over a period of 8 weeks. The therapeutic effects, T cell infiltration and differentiation of WCP on MRL/lpr mice were verified through ELISA, Hematoxylin-eosin (H&E), Periodic Acid Schiff (PAS) staining, immunofluorescence, Luminex analysis and flow cytometry. The mechanism by which WCP alleviates LN was investigated using tissues of mice, T cells and Mouse Podocyte Clone-5 (MPC-5) cells by transcriptomics, Western blot (WB), and Real-time quantitative polymerase chain reaction (RT-qPCR). RESULTS: We found that WCP improved LN in MRL/lpr mice by reducing urinary protein, creatinine, and serum auto antibodies, increasing complement 3 (C3) level, improving renal immunopathology and downregulating serum cytokines, including IFN-γ, IL-12, and RANTES. Notably, the infiltration of CD4+ and CD8+ T cells in the kidney was reduced by WCP. Similarly, the cell transwell co-culturation study showed that the WCP treated MPC-5 cells were weaker in inducing T cell migration. Consistent with this finding, our observations revealed that WCP could inhibit T cell-related chemokine expression in kidney and MPC-5 cells, as well as reduce the levels of TLR4, MYD88, phosphorylated-p38, phosphorylated-ERK, and phosphorylated-JNK. On the other hand, WCP was found to greatly inhibit the Th1 cells differentiation in vivo and in vitro. Cytokine-receptor induced Th1 cell differentiation pathway and PI3K-AKT pathway were the most enriched pathways based on differentially expressed genes (DEGs) enrichment analysis among different cell groups. Results from RT-qPCR and WB showed that WCP notably reduced the levels of IL-12, p-STAT4, IFN-γ, p-STAT1, p-PI3K, and p-AKT in T cells. CONCLUSION: WCP demonstrated positive immunomodulatory effects on LN disease, by decreasing the T cells infiltration through TLR4/MYD88/MAPK signaling pathway and inhibiting Th1 cells differentiation via IL-12-STAT4 and IFN-γ-STAT1 pathways, in addition to the PI3K-AKT pathway.


Assuntos
Diferenciação Celular , Cordyceps , Rim , Nefrite Lúpica , Camundongos Endogâmicos MRL lpr , Células Th1 , Animais , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , Cordyceps/química , Diferenciação Celular/efeitos dos fármacos , Células Th1/imunologia , Células Th1/efeitos dos fármacos , Camundongos , Feminino , Rim/patologia , Rim/efeitos dos fármacos , Rim/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos
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