Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 147
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 120(1): e2215484119, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36574683

RESUMEN

We report the discovery of a dodecagonal quasicrystal Mn72.3Si15.6Cr9.7Al1.8Ni0.6-composed of a periodic stacking of atomic planes with quasiperiodic translational order and 12-fold symmetry along the two directions perpendicular to the planes-accidentally formed by an electrical discharge event in an eolian dune in the Sand Hills near Hyannis, Nebraska, United States. The quasicrystal, coexisting with a cubic crystalline phase with composition Mn68.9Si19.9Ni7.6Cr2.2Al1.4, was found in a fulgurite consisting predominantly of fused and melted sand along with traces of melted conductor metal from a nearby downed power line. The fulgurite may have been created by a lightning strike that combined sand with material from downed power line or from electrical discharges from the downed power line alone. Extreme temperatures of at least 1,710 °C were reached, as indicated by the presence of SiO2 glass in the sample. The dodecagonal quasicrystal is an example of a quasicrystal of any kind formed by electrical discharge, suggesting other places to search for quasicrystals on Earth or in space and for synthesizing them in the laboratory.

2.
Nano Lett ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958407

RESUMEN

Piwi-interacting RNAs (piRNAs) are small noncoding RNAs that repress transposable elements to maintain genome integrity. The canonical catalytic hairpin assembly (CHA) circuit relies on random collisions of free-diffused reactant probes, which substantially slow down reaction efficiency and kinetics. Herein, we demonstrate the construction of a spatial-confined self-stacking catalytic circuit for rapid and sensitive imaging of piRNA in living cells based on intramolecular and intermolecular hybridization-accelerated CHA. We rationally design a 3WJ probe that not only accelerates the reaction kinetics by increasing the local concentration of reactant probes but also eliminates background signal leakage caused by cross-entanglement of preassembled probes. This strategy achieves high sensitivity and good specificity with shortened assay time. It can quantify intracellular piRNA expression at a single-cell level, discriminate piRNA expression in tissues of breast cancer patients and healthy persons, and in situ image piRNA in living cells, offering a new approach for early diagnosis and postoperative monitoring.

3.
Anal Chem ; 96(1): 599-605, 2024 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-38156620

RESUMEN

Circular RNAs (circRNAs) represent an emerging category of endogenous transcripts characterized by long half-life time, covalently closed structures, and cell-/tissue-specific expression patterns, making them potential disease biomarkers. Herein, we demonstrate the construction of fluorescent G-quadruplex nanowires for label-free and accurate monitoring of circular RNAs in breast cancer cells and tissues by integrating proximity ligation-rolling circle amplification cascade with lighting up G-quadruplex. The presence of target circRNA facilitates the SplintR ligase-mediated ligation of the padlock probe. Upon the addition of primers, the ligated padlock probe can serve as a template to initiate subsequent rolling circle amplification (RCA), generating numerous long G-quadruplex nanowires that can incorporate with thioflavin T (ThT) to generate a remarkably improved fluorescence signal. Benefiting from good specificity of SplintR ligase-mediated ligation reaction and exponential amplification efficiency of RCA, this strategy can sensitively detect target circRNA with a limit of detection of 4.65 × 10-18 M. Furthermore, this method can accurately measure cellular circRNA expression with single-cell sensitivity and discriminate the circRNA expression between healthy para-carcinoma tissues and breast cancer tissues, holding great potential in studying the pathological roles of circRNA and clinic diagnostics.


Asunto(s)
Neoplasias de la Mama , Nanocables , Humanos , Femenino , ARN Circular , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , Colorantes Fluorescentes/química , Ligasas , Técnicas de Amplificación de Ácido Nucleico/métodos
4.
J Appl Toxicol ; 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760888

RESUMEN

Multidrug and toxin extrusion protein 1 (MATE1), an efflux transporter mainly expressed in renal proximal tubules, mediates the renal secretion of organic cationic drugs. The inhibition of MATE1 will impair the excretion of drugs into the tubular lumen, leading to the accumulation of nephrotoxic drugs in the kidney and consequently potentiating nephrotoxicity. Screening and identifying potent MATE1 inhibitors can predict or minimize the risk of drug-induced kidney injury. Flavonoids, a group of polyphenols commonly found in foodstuffs and herbal products, have been reported to cause transporter-mediated food/herb-drug interactions. Our objective was to investigate the inhibitory effects of flavonoids on MATE1 in vitro and in vivo and to assess the effects of flavonoids on cisplatin-induced kidney injury. Thirteen flavonoids exhibited significant transport activity inhibition (>50%) on MATE1 in MATE1-MDCK cells. Among them, the six strongest flavonoid inhibitors, including irisflorentin, silymarin, isosilybin, sinensetin, tangeretin, and nobiletin, markedly increased cisplatin cytotoxicity in these cells. In cisplatin-induced in vivo renal injury models, irisflorentin, isosilybin, and sinensetin also increased serum creatinine and blood urea nitrogen levels to different degrees, especially irisflorentin, which exhibited the most potent nephrotoxicity with cisplatin. The pharmacophore model indicated that the hydrogen bond acceptors at the 3, 5, and 7 positions may play a critical role in the inhibitory effect of flavonoids on MATE1. Our findings provide helpful information for predicting the potential risks of flavonoid-containing food/herb-drug interactions and avoiding the exacerbation of drug-induced kidney injury via MATE1 mediation.

5.
J Asian Nat Prod Res ; 26(3): 353-371, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37589480

RESUMEN

The organic anion transporter 3 (OAT3), an important renal uptake transporter, is associated with drug-induced acute kidney injury (AKI). Screening and identifying potent OAT3 inhibitors with little toxicity in natural products, especially flavonoids, in reducing OAT3-mediated AKI is of great value. The five strongest OAT3 inhibitors from the 97 flavonoids markedly decreased aristolochic acid I-induced cytotoxicity and alleviated methotrexate-induced nephrotoxicity. The pharmacophore model clarified hydrogen bond acceptors and hydrophobic groups are the critical pharmacophores. These findings would provide valuable information in predicting the potential risks of flavonoid-containing food/herb-drug interactions and optimizing flavonoid structure to alleviate OAT3-related AKI.


Asunto(s)
Lesión Renal Aguda , Flavonoides , Transportadores de Anión Orgánico Sodio-Independiente , Lesión Renal Aguda/tratamiento farmacológico , Lesión Renal Aguda/metabolismo , Transporte Biológico , Flavonoides/farmacología , Flavonoides/química , Transportadores de Anión Orgánico/efectos de los fármacos , Transportadores de Anión Orgánico/metabolismo , Relación Estructura-Actividad , Transportadores de Anión Orgánico Sodio-Independiente/efectos de los fármacos , Transportadores de Anión Orgánico Sodio-Independiente/metabolismo
6.
Anal Chem ; 95(12): 5454-5462, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36930460

RESUMEN

N6-Methyladenosine (m6A) has emerged as a key post-transcriptional regulator in mRNA metabolism, and its dysregulation is associated with multiple human diseases. Herein, we construct a single-molecule fluorescent biosensor for antibody-free detection of locus-specific m6A in cancer cells and tissues. A 5'-biotinylated capture probe and a 3'-hydroxylated assistant probe are designed for the recognition of specific m6A-mRNA. The m6A-sensitive endoribonuclease MazF can identify and cleave the unmethylated mRNA, and the retained intact m6A-mRNA can hybridize with assistant probes and capture probes to achieve sandwich hybrids. The sandwich hybrids are immobilized on magnetic beads (MBs) to initiate the terminal deoxynucleotidyl transferase (TdT)-assisted polymerization, facilitating the continuous incorporation of Cy5-dATP to form long Cy5-polyA tails for the production of an on-bead amplified fluorescence signal. After magnetic separation and exonuclease digestion, numerous Cy5 fluorophores are released and subsequently measured by single-molecule detection. Especially, this biosensor is implemented simply and isothermally without the involvement of either radiolabeling or m6A-specific antibody. Moreover, this biosensor shows ultrahigh sensitivity with a detection limit of 2.24 × 10-17 M, and it can discriminate a 0.01% m6A level from a large pool of coexisting counterparts. Furthermore, this biosensor can be used for monitoring cellular m6A-mRNA expression and differentiating the m6A level in the breast cancer patient tissues from that in the healthy person tissues, providing a new avenue for clinical diagnosis and epitranscriptomic research.


Asunto(s)
Técnicas Biosensibles , Neoplasias , Humanos , Límite de Detección , Neoplasias/diagnóstico
7.
Anal Chem ; 95(48): 17945-17953, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-38000786

RESUMEN

N6-Methyladenosine (m6A) is the most pervasive and evolutionarily conserved epitranscriptomic modification in long noncoding RNA (lncRNA), and its dysregulation may induce aberrant transcription and translation programs. Herein, we demonstrate the methylation-powered assembly of a single quantum dot (QD)-based fluorescence resonance energy transfer (FRET) nanosensor for antibody- and enzyme-free monitoring of locus-specific m6A in clinical tissues. The m6A-sensitive DNAzyme VMC10 is employed to identify a specific m6A site in lncRNA, and it catalyzes the hydrolytic cleavage of unmethylated lncRNA. The cleaved lncRNA fails to trigger the subsequent catalytic hairpin assembly (CHA) reaction due to the energy barrier. In contrast, when m6A-lncRNA is present, the methyl group in m6A protects lncRNA from VMC10-mediated cleavage. With the aid of an assistant probe, the retained intact m6A-lncRNA is released from the VMC10/lncRNA complex and subsequently triggers the CHA reaction, generating abundant AF647/biotin dual-labeled duplexes. The assembly of AF647/biotin dual-labeled duplexes onto 605QD results in efficient FRET between 605QD and AF647. The FRET signal can be simply quantified by single-molecule detection. Notably, this assay can be implemented in an antibody-free and enzyme-free manner. This nanosensor can sensitively quantify target m6A with a detection limit of 0.47 fM, and it can discriminate as low as a 0.001% m6A level from excess coexisting counterparts. Importantly, this nanosensor can monitor the cellular m6A level with single-cell sensitivity and profile target m6A expression in breast cancer and healthy para-cancerous tissues, providing a powerful tool for studying the physiological and pathological functions of m6A.


Asunto(s)
Técnicas Biosensibles , Puntos Cuánticos , ARN Largo no Codificante , Transferencia Resonante de Energía de Fluorescencia/métodos , Metilación , Biotina , ARN Largo no Codificante/genética , Anticuerpos
8.
Int Arch Occup Environ Health ; 96(10): 1361-1371, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37874403

RESUMEN

BACKGROUND AND PURPOSE: Efforts to improve nurses' physical and mental health are critical to ensuring the safety and quality of the healthcare system. Long-term studies targeting the relevancy of nurses' occupation characteristics with health conditions remain insufficient. This study aimed to examine the relationship between nurses' night shift and sleep problems and metabolic abnormalities risk. METHODS: This study was a part of the National Nurse Health Study, an ambispective cohort study in China, in 2021. Based on an integration physical examination data system, this study carried out a retrospective analysis of 730 nurses from 2018 to 2020 and combined with a questionnaire survey in 2021. The STROBE guidelines were adopted for reporting. RESULTS: In the 23 (23.0, 24.0) months follow-up, higher night shift load was associated with more sleep problems such as shortened sleep duration, sleep disorders, poor sleep quality, and sleep deprivation. Moreover, night shift load was associated with chronic diseases risk factors, increasing body mass index and body fat, with more night shift density, increasing the occurrence of low levels of high-density lipoprotein cholesterol, high triglyceride, triglyceride/high-density lipoprotein cholesterol ratio, and serum uric acid. CONCLUSION: The night shift load has become an occupational health concern, contributing to chronic diseases relevant metabolic risk factors and negative influence on sleep health. Focus on the strategies to improve the sleep quality of nurses undergoing night shift work, optimize work scheduling and ongoing monitor the relevant risk factors are essential to enhance the stability and well-being of the nursing workforce. CLINICAL TRIALS REGISTRATION INFORMATION: NCT04572347, on October 1, 2020. https://www. CLINICALTRIALS: gov/ct2/show/NCT04572347.


Asunto(s)
Enfermeras y Enfermeros , Tolerancia al Trabajo Programado , Humanos , Estudios Retrospectivos , Estudios de Cohortes , Estudios de Seguimiento , Ácido Úrico , Sueño , Privación de Sueño , Enfermedad Crónica , Triglicéridos , Lipoproteínas HDL , Colesterol
9.
J Appl Toxicol ; 43(10): 1421-1435, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37057715

RESUMEN

Organic cation transporter 2 (OCT2) is mainly responsible for the renal secretion of various cationic drugs, closely associated with drug-induced acute kidney injury (AKI). Screening and identifying potent OCT2 inhibitors with little toxicity in natural products in reducing OCT2-mediated AKI is of great value. Flavonoids are enriched in various vegetables, fruits, and herbal products, and some were reported to produce transporter-mediated drug-drug interactions. This study aimed to screen potential inhibitors of OCT2 from 96 flavonoids, assess the nephroprotective effects on cisplatin-induced kidney injury, and clarify the structure-activity relationships of flavonoids with OCT2. Ten flavonoids exhibited significant inhibition (>50%) on OCT2 in OCT2-HEK293 cells. Among them, the six most potent flavonoid inhibitors, including pectolinarigenin, biochanin A, luteolin, chrysin, 6-hydroxyflavone, and 6-methylflavone markedly decreased cisplatin-induced cytotoxicity. Moreover, in cisplatin-induced renal injury models, they also reduced serum blood urea nitrogen (BUN) and creatinine levels to different degrees, the best of which was 6-methylflavone. The pharmacophore model clarified that the aromatic ring, hydrogen bond acceptors, and hydrogen bond donors might play a vital role in the inhibitory effect of flavonoids on OCT2. Thus, our findings would pave the way to predicting the potential risks of flavonoid-containing food/herb-drug interactions in humans and optimizing flavonoid structure to alleviate OCT2-related AKI.


Asunto(s)
Lesión Renal Aguda , Cisplatino , Humanos , Transportador 2 de Cátion Orgánico/metabolismo , Cisplatino/toxicidad , Proteínas de Transporte de Catión Orgánico/metabolismo , Células HEK293 , Flavonoides/farmacología , Relación Estructura-Actividad , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/prevención & control
10.
Ophthalmic Res ; 66(1): 1300-1307, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37812921

RESUMEN

INTRODUCTION: This real-world study evaluated the efficacy, safety, and operative parameters of two perfluoropropane (C3F8) tamponade methods combined with pars plana vitrectomy (PPV) for retinal detachment (RD). METHODS: A retrospective study of 132 patients (132 eyes) with RD (pure C3F8 in 38 eyes, mixed C3F8 in 94 eyes). All eyes underwent PPV with C3F8 tamponade and were followed up for at least 3 months. Retinal reattachment rate, time of gas configuration and injection, C3F8 dosage, intraocular pressure (IOP), best corrected visual acuity, postoperative ocular inflammation, and patients' complaints were evaluated. RESULTS: The single-surgery retinal reattachment rates of the pure C3F8 group and mixed C3F8 group were 97.4% and 96.8%, respectively, with no significant difference (p = 1.00). The final retinal reattachment rates of the two groups were 100% and 97.2%, respectively, with no significant difference (p = 1.00). The gas configuration time, gas injection time, and C3F8 dosage were significantly less in the pure C3F8 group (all p < 0.001). Time, but not group, was the influencing factor of postoperative IOP changes in the two groups (p < 0.001, p = 0.547, respectively). Compared with the baseline, the IOP estimates of the pure C3F8 group showed a significant increase immediately after surgery (p < 0.001), and the mixed C3F8 group showed a significant increase immediately and 1-2 days after surgery (all p < 0.05). There was no statistical difference in ocular inflammation (p = 0.339) and patients' complaints of discomfort (p = 0.175) between the two groups. CONCLUSION: Both the two methods of C3F8 tamponade combined with PPV in RD patients showed good efficacy and safety, but the clinical operation of pure C3F8 tamponade was more convenient and eco-friendly.


Asunto(s)
Desprendimiento de Retina , Perforaciones de la Retina , Humanos , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/cirugía , Vitrectomía/métodos , Estudios Retrospectivos , Retina , Inflamación , Perforaciones de la Retina/cirugía
11.
Cogn Process ; 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38064117

RESUMEN

This research aims to study the impact of implicit emotion on the use of theory of mind and enrich the research on emotions and the use of theory of mind, thus allowing adults to apply theory of mind more effectively in the context of social interaction. This study includes 120 college students as participants. A two (level of theory of mind: high vs. low) * three (implicit emotional state: implicit positive emotion, implicit neutral emotion, or implicit negative emotion) * two (private knowledge: endowed vs. unendowed) between-subjects three-factor design was employed. This study obtained the following results: (1) The main effect of different implicit emotional states on college students' use of theory of mind is significant. College students with implicit positive emotions use theory of mind much less than those with implicit neutral and negative emotions. (2) In cases of implicit positive emotions, college students with a low level of theory of mind use theory of mind substantially less than students with a high level of theory of mind. In cases of implicit neutral and negative emotions, college students with the high and low theory of mind do not exhibit substantial differences in their use of theory of mind. This study concludes that different emotional states affect college students' use of theory of mind.

12.
Anal Chem ; 94(3): 1882-1889, 2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35000391

RESUMEN

MicroRNAs (miRNAs) play multiple crucial roles in post-transcriptional regulating gene expression, and the abnormal expression may induce various human diseases. Herein, we demonstrate the construction of a structure-switchable toehold dumbbell probe for sensitive and label-free measurement of microRNA in cancer cells and tissues on the basis of integrating exponential-rolling circle amplification (EXP-RCA) with linear-rolling circle amplification (LRCA). We designed a structure-switchable toehold dumbbell probe with annular and symmetric structure whose either side can hybridize with target miRNA to initiate EXP-RCA, greatly improving the detection sensitivity. Moreover, the dumbbell probe is designed with an appropriate standard free energy (G), and it cannot be activated by mismatched miRNAs, endowing this assay with good specificity. When target miRNA is present, it interacts with the dumbbell probe to activate EXP-RCA via toehold-mediated stand displacement, generating abundant triggers. The resulting triggers and target miRNA can function as primers to initiate LRCA, producing abundant long tandem repeats that can generate a distinct fluorescence signal using SYBR Gold as the indicator. This assay can be carried out homogeneously and isothermally without the requirement for either sophisticated modification/separation steps or any extra primers. It displays ultrahigh sensitivity with a limit of detection of 8.45 × 10-17 M and excellent specificity, and it can differentiate let-7a from its homologous analogues. Moreover, this method can accurately quantify let-7a expression at a single-cell level and can even distinguish the let-7a expression between non-small cell lung cancer patient tissues and healthy person tissues.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , Cartilla de ADN , Humanos , Límite de Detección , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , MicroARNs/genética , Técnicas de Amplificación de Ácido Nucleico/métodos
13.
Anal Chem ; 94(44): 15171-15175, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36305672

RESUMEN

MicroRNA (miRNA)-related single-nucleotide polymorphisms (miR-SNPs) are a novel class of genetic variations involved in multiple cellular functions, and they have emerged as promising biomarkers for cancer diagnostics and prognostics. Herein, we demonstrate for the first time the structure-switchable hairpin-powered exponential replications for sensing attomolar miR-SNPs in human cancer tissues with zero background. In the presence of target miR-196a2T, hairpin probes (i.e., HP1 and HP2) are splinted together to construct the dumbbell-shaped probe (DSP) with SplintR ligase catalysis. Once the DSP is formed, the self-primed polymerization extension and linear FIP/BIP-primed strand displacement DNA synthesis (SDS) are automatically repeated to activate self-circulated exponential amplification, producing large amounts of double-stranded DNAs (dsDNAs) which can be real-time monitored using SYBR Green I. This nanodevice can detect miR-196a2T with an ultralow detection limit of 2.46 aM; distinguish rare miR-196a2 SNP with a selectivity factor of 0.001%; and even profile miR-196a2T in human tissues for nonsmall cell lung cancer (NSCLC) diagnosis, risk assessment, and cancer type prediction. Notably, this nanodevice can be rapidly and homogeneously used in one tube in a real-time and label-free manner, providing a powerful point-of-care platform for noninvasive diagnostics and prognostics of miR-SNPs-related human cancers.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , Humanos , MicroARNs/genética , Polimorfismo de Nucleótido Simple , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , ADN , Técnicas de Amplificación de Ácido Nucleico
14.
Langmuir ; 38(44): 13392-13400, 2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36279423

RESUMEN

Considerable attention has been paid to on-surface Ullmann coupling during the past decade owing to the feasible synthesis of artificial nanostructures. While previous reports mainly concentrated on coupling reactions on single-metal-atom surfaces, herein we present the Ullmann coupling of 2,7-dibromopyrene (Br2Py) on bimetallic surfaces, Bi-Ag(111) and Bi-Au(111), respectively, with scanning tunneling microscopy (STM) and X-ray photoemission spectroscopy (XPS). On the Bi-decorated Ag(111), self-assembly of intact Br2Py is realized due to the reduced activity at the interface. Subsequent annealing promotes the dehalogenation of Br2Py on Bi-Ag(111), while Bi adatoms do not bring any visible influence on coupling reactions. Furthermore, post-deposition of Bi onto preassembled nanostructures on Ag(111) immediately initiates the Ullmann coupling by inducing more Ag adatoms available on the surface, while stepwise annealing afterward leads to complete polymerization and formation of covalent chains with lateral displacement compared to that on the bare Ag(111), probably due to the space hindrance and confinement. For Bi-Au(111) with the modified reconstruction, higher-temperature annealing is required to trigger Ullmann coupling compared to that on Au(111). The exception is that the C-C coupling reaction remains impervious to Bi adatoms, and recovery of the Bi-Au reconstruction is realized after intensive annealing. In principle, bimetallic surfaces herein present intriguing behavior toward the controllable Ullmann coupling, and this report might provide different insights into the comprehensive atomistic elucidation of reaction mechanisms as well as the design of a new platform to effectively regulate Ullmann coupling.

15.
Anal Chem ; 93(43): 14568-14576, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34672523

RESUMEN

Single-nucleotide polymorphisms (SNPs) are important hallmarks of human diseases. Herein, we develop a single quantum dot (QD)-mediated fluorescence resonance energy transfer (FRET) nanosensor with the integration of multiple primer generation rolling circle amplification (MPG-RCA) for sensitive detection of SNPs in cancer cells. This assay involves only a linear padlock probe for MPG-RCA. The presence of a mutant target facilitates the circularization of linear padlock probes to initiate RCA, producing three short single-stranded DNAs (ssDNAs) with the assistance of nicking endonuclease. The resulting ssDNAs can function as primers to induce cyclic MPG-RCA, resulting in the exponential amplification and generation of large numbers of linker probes. The linker probes can subsequently hybridize with the Cy5-labeled reporter probes and the biotinylated capture probes to obtain the sandwich hybrids. The assembly of these sandwich hybrids on the 605 nm-emission quantum dot (605QD) generates the 605QD-oligonucleotide-Cy5 nanostructures, resulting in efficient FRET from the 605QD to Cy5. This nanosensor is free from both the complicated probe design and the exogenous primers and has distinct advantages of high amplification efficiency, zero background signal, good specificity, and high sensitivity. It can detect SNPs with a large dynamic range of 8 orders of magnitude and a detection limit of 5.41 × 10-20 M. Moreover, this nanosensor can accurately distinguish as low as 0.001% mutation level from the mixtures, which cannot be achieved by previously reported methods. Furthermore, it can discriminate cancer cells from normal cells and even quantify SNP at the single-cell level.


Asunto(s)
Neoplasias , Puntos Cuánticos , Humanos , ADN de Cadena Simple , Transferencia Resonante de Energía de Fluorescencia , Neoplasias/genética , Técnicas de Amplificación de Ácido Nucleico , Polimorfismo de Nucleótido Simple
16.
Rheumatology (Oxford) ; 60(3): 1067-1079, 2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33677596

RESUMEN

BACKGROUND: Clinical relapses are common in patients with ANCA-associated vasculitis (AAV). The aim of this systematic review was to estimate time-point prevalence and risk factors of relapse. METHODS: We searched PubMed, Embase, and Cochrane Library databases from their inception to March 30, 2020. Cohorts and post-hoc studies were included for the estimation of summary cumulative relapse rates (CRRs) and adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs). Sensitivity and meta-regression analyses were also performed. RESULTS: Of the 42 eligible studies, 24 studies with 6236 participants were used for the pooled analyses of CRRs. The summary 1-year, 3-year, and 5-year CRRs were 0.12 (95% CI, 0.10-0.14), 0.33 (0.29-0.38), and 0.47 (0.42-0.52), respectively. In meta-regressions, the baseline age was positively associated with 1-year CRR. The proportion of granulomatosis with polyangiitis was positively associated with 5-year CRR. Twenty-eight studies with 5390 participants were used for the meta-analysis of risk factors for relapse, including a lower level of baseline serum creatine, proteinase 3 (PR3)-ANCA positivity at diagnosis, an ANCA rise, extrarenal organ involvement (including lung, cardiovascular, upper respiratory, and gastrointestinal involvement), intravenous (vs oral) cyclophosphamide induction, a shorter course of immunosuppressant maintenance, and maintenance with mycophenolate mofetil (vs azathioprine). CONCLUSIONS: Our systematic review demonstrated that the 1-year, 3-year, and 5-year cumulative probabilities of relapse were ∼12%, 33%, and 47% in AAV patients receiving cyclophosphamide induction, respectively. Early identification of risk factors for relapse is helpful to the risk stratification of patients so as to achieve personalized treatment.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/tratamiento farmacológico , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/epidemiología , Ciclofosfamida/administración & dosificación , Humanos , Inmunosupresores/administración & dosificación , Prevalencia , Recurrencia , Factores de Riesgo
17.
Anal Biochem ; 631: 114357, 2021 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-34469746

RESUMEN

The growth and proliferation of most cancer cells involve the excessive uptake of glucose mediated by glucose transporters. An effective strategy for cancer therapy has been to inhibit the GLUTs that are usually overexpressed in a variety of tumor cells. 2-NBDG is a GLUT1 substrate that can be used as a probe for GLUT1 inhibitors. An accurate and simple assay for 2-NBDG in a HEK293T cell model overexpressing GLUT1 was developed using liquid chromatography-tandem mass spectrometry. Chromatographic separation was achieved using a Xbridge® Amide column (3.5 µm, 2.1 mm × 150 mm, Waters) with acetonitrile-water containing 2 µM ammonium acetate (80:20, v/v) at a flow rate of 0.25 mL/min. Mass detection was conducted in the parallel reaction monitoring (PRM) mode. The calibration curve for 2-NBDG showed good linearity in the concentration range of 5-500 ng/mL with satisfactory precision, a relative standard deviation ranging from 2.92 to 9.59% and accuracy with a relative error ranging from -13.14 to 7.34%. This method was successfully applied to quantify the uptake of GLUT1-mediated 2-NBDG, and the results clearly indicated inhibition of GLUT1 by WZB117 and quercetin (two potent glucose transporter inhibitors) in the GLUT1-HEK293T cell model. This study provides a convenient and accurate method for high-throughput screening of selective and promising GLUT1 inhibitors.


Asunto(s)
4-Cloro-7-nitrobenzofurazano/análogos & derivados , Cromatografía Liquida/métodos , Desoxiglucosa/análogos & derivados , Transportador de Glucosa de Tipo 1/metabolismo , Espectrometría de Masas en Tándem/métodos , 4-Cloro-7-nitrobenzofurazano/análisis , Desoxiglucosa/análisis , Estabilidad de Medicamentos , Glucosa/farmacocinética , Transportador de Glucosa de Tipo 1/genética , Células HEK293 , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Bioorg Chem ; 111: 104973, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34004586

RESUMEN

Parthenolide and micheliolide have attracted great attention in anticancer research due to their unique activities. In this study, thirteen parthenolide derivatives and twenty-three micheliolide derivatives were synthesized. Most synthesized compounds showed higher cytotoxicity than parthenolide or micheliolide. The in vivo anticancer activity of several representative compounds was evaluated in mice. One micheliolide derivative, 9-oxomicheliolide (43), showed promising in vivo antitumor activity compared with clinical drugs cyclophosphamide or temozolomide. Compound 43 was particularly effective against glioblastoma, with its tumor inhibition rate in mice comparable to the drug temozolomide. The discovery of compound 43 also demonstrates the feasibility of developing anticancer micheliolide derivatives by modification at C-9 position. Anticancer mechanism studies revealed that 9-oxomicheliolide exhibited inhibition effect against NF-κB and STAT3 signaling pathways, as well as induction effects of cell apoptosis. It is postulated that 9-oxomicheliolide is likely to be a modulator of the immune system, which regulates the anticancer immune responses.


Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , FN-kappa B/antagonistas & inhibidores , Factor de Transcripción STAT3/antagonistas & inhibidores , Sesquiterpenos de Guayano/farmacología , Sesquiterpenos/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Masculino , Ratones , Ratones Endogámicos , Estructura Molecular , FN-kappa B/metabolismo , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Factor de Transcripción STAT3/metabolismo , Sesquiterpenos/síntesis química , Sesquiterpenos/química , Sesquiterpenos de Guayano/síntesis química , Sesquiterpenos de Guayano/química , Relación Estructura-Actividad , Células Tumorales Cultivadas
19.
Genomics ; 112(5): 3668-3676, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32360888

RESUMEN

Heat stress (HS) seriously affects sow lactation performance and Long non-coding RNAs (lncRNAs) play vital roles in the regulation of transcription and post transcription. However, the mechanism of lncRNAs expression affecting lactation performance on the hypothalamus-pituitary-mammary axis of sows is still unclear. In this study, we performed RNA sequencing and bioinformatics analysis of the hypothalamus, pituitary, and mammary gland tissues of lactating sows under HS and thermal comfort. In total, the analysis identified 658, 6021, and 6745 differently expressed (DE) mRNAs, 26, 126, and 169 DE lncRNAs between comparison groups in the hypothalamus, pituitary, and mammary glands, respectively. The hormone genes and most DE mRNAs encoding heat shock protein were differently expressed in the HS group. In addition, 2, 60, and 86 pairs of DE lncRNAs and mRNAs correlation were observed in those tissues, respectively. Some lncRNAs may be involved in the regulation of lactation performance in the HS sows.


Asunto(s)
Respuesta al Choque Térmico , Hipotálamo/metabolismo , Glándulas Mamarias Animales/metabolismo , Hipófisis/metabolismo , ARN Largo no Codificante/genética , ARN Mensajero/genética , Animales , Femenino , Perfilación de la Expresión Génica , Reproducibilidad de los Resultados , Porcinos
20.
Molecules ; 26(2)2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33477555

RESUMEN

13a-(S)-3-pivaloyloxyl-6,7-dimethoxyphenanthro(9,10-b)-indolizidine (CAT3) is a novel oral anti-glioma pro-drug with a potent anti-tumor effect against temozolomide-resistant glioma. 13a(S)-3-hydroxyl-6,7-dimethoxyphenanthro(9,10-b)-indolizidine (PF403) is the active in vivo lipase degradation metabolite of CAT3. Both CAT3 and PF403 can penetrate the blood-brain barrier to cause an anti-glioma effect. However, PF403, which is produced in the gastrointestinal tract and plasma, causes significant gastrointestinal side effects, limiting the clinical application of CAT3. The objective of this paper was to propose a metabolism modification for CAT3 using a self-microemulsifying drug delivery system (SMEDDS), in order to reduce the generation of PF403 in the gastrointestinal tract and plasma, as well as increase the bioavailability of CAT3 in vivo and the amount of anti-tumor substances in the brain. Thus, a CAT3-loaded self-microemulsifying drug delivery system (CAT3-SMEDDS) was prepared, and its physicochemical characterization was systematically carried out. Next, the pharmacokinetic parameters of CAT3 and its metabolite in the rats' plasma and brain were measured. Furthermore, the in vivo anti-glioma effects and safety of CAT3-SMEDDS were evaluated. Finally, Caco-2 cell uptake, MDCK monolayer cellular transfer, and the intestinal lymphatic transport mechanisms of SMEDDS were investigated in vitro and in vivo. Results show that CAT3-SMEDDS was able to form nanoemulsion droplets in artificial gastrointestinal fluid within 1 min, displaying an ideal particle size (15-30 nm), positive charge (5-9 mV), and controlled release behavior. CAT3-SMEDDS increased the membrane permeability of CAT3 by 3.9-fold and promoted intestinal lymphatic transport. Hence, the bioavailability of CAT3 was increased 79% and the level of its metabolite, PF403, was decreased to 49%. Moreover, the concentrations of CAT3 and PF403 were increased 2-6-fold and 1.3-7.2-fold, respectively, in the brain. Therefore, the anti-glioma effect in the orthotopic models was improved with CAT3-SMEDDS compared with CAT3 in 21 days. Additionally, CAT3-SMEDDS reduced the gastrointestinal side effects of CAT3, such as severe diarrhea, necrosis, and edema, and observed less inflammatory cell infiltration in the gastrointestinal tract, compared with the bare CAT3. Our work reveals that, through the metabolism modification effect, SMEDDS can improve the bioavailability of CAT3 and reduce the generation of PF403 in the gastrointestinal tract and plasma. Therefore, it has the potential to increase the anti-glioma effect and reduce the gastrointestinal side effects of CAT3 simultaneously.


Asunto(s)
Antineoplásicos/farmacología , Sistemas de Liberación de Medicamentos , Glioblastoma/tratamiento farmacológico , Indolicidinas/farmacología , Fenantrenos/farmacología , Animales , Disponibilidad Biológica , Perros , Liberación de Fármacos , Emulsiones , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Células de Riñón Canino Madin Darby , Masculino , Ratones , Ratones Endogámicos ICR , Ratas , Ratas Sprague-Dawley
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA