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1.
Angew Chem Int Ed Engl ; : e202410710, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949854

RESUMO

Metallo-supramolecular cages have garnered tremendous attention for their diverse yet molecular-level precision structures. However, physical properties of these supramolecular ensembles, which are of potential significance in molecular electronics, remain largely unexplored. We herein constructed a series of octahedral metallo-cages and cage-fullerene complexes with notably enhanced structural stability. As such, we could systematically evaluate the electrical conductivity of these ensembles at both single-molecule level and aggregated bulk state (as well-defined films). Our findings reveal that counteranions and fullerene guests play a pivotal role in determining the electrical conductivity of aggregated state, while such effects are less significant for single-molecule conductance. Both counteranions and fullerenes effectively tune the electronic structures and packing density of metallo-supramolecular assemblies, and facilitate efficient charge transfer between the cage hosts and fullerenes, resulting in a notable one order of magnitude increase in electrical conductivity of the aggregated state.

2.
Molecules ; 29(11)2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38893316

RESUMO

For designing single-molecule devices that have both conjugation systems and structural flexibility, a hyperconjugated molecule with a σ-π bond interaction is considered an ideal candidate. In the investigation of conductance at the single-molecule level, since few hyperconjugation systems have been involved, the strategy of building hyperconjugation systems and the mechanism of electron transport within this system remain unexplored. Based on the skipped-conjugated structure, we present a rational approach to construct a hyperconjugation molecule using a hydroxyl group, which serves as a bridge to interact with the conjugated fragments. The measurement of single-molecule conductance reveals a two-fold conductance enhancement of the hyperconjugation system having the 'bridging' hydroxyl group compared to hydroxyl-free derivatives. Theoretical studies demonstrate that the hydroxyl group in the hyperconjugation system connects the LUMO of the two conjugated fragments and opens a through-space channel for electron transport to enhance the conductance.

4.
Langmuir ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332611

RESUMO

An asymmetric structure is an important strategy for designing highly conductive molecular wires for a gap-fixed molecular circuit. As the conductance enhancement in the current strategy is still limited to about 2 times, we inserted a methylene group as a spacer in a conjugated structure to modulate the structural symmetry. We found that the conductance drastically enhanced in the asymmetric molecular wire to 1.5 orders of magnitude as high as that in the symmetric molecular wire. First-principles quantum transport studies attributed the effective enhancement to the synchronization of improved energy alignment and nearly symmetric coupling between the frontier orbitals and the electrodes.

5.
Clin Case Rep ; 11(12): e8289, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38084356

RESUMO

There are no reports of application of inotuzumab ozogamicin (InO) for the treatment of MRD in r/r B-ALL. We firstly report the efficacy of InO for a patient experienced morphological relapse after HSCT and molecular relapse after CART therapy.

6.
Nano Lett ; 23(20): 9399-9405, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37877237

RESUMO

An accurate rule for predicting conductance is the cornerstone of developing molecular circuits and provides a promising solution for miniaturizing electric circuits. The successful prediction of series molecular circuits has proven the possibility of establishing a rule for molecular circuits under quantum mechanics. However, the quantitatively accurate prediction has not been validated by experiments for parallel molecular circuits. Here we used 1,3-dihydrobenzothiophene (DBT) to build the parallel molecular circuits. The theoretical simulation and single-molecule conductance measurements demonstrated that the conductance of the molecule containing one DBT is the unprecedented linear combination of the conductance of the two individual channels with respective contribution weights of 0.37 and 0.63. With these weights, the conductance of the molecule containing two DBTs is predicted as 1.81 nS, matching perfectly with the measured conductance (1.82 nS). This feature offers a potential rule for quantitatively predicting the conductance of parallel molecular circuits.

7.
BMC Med ; 21(1): 270, 2023 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488510

RESUMO

BACKGROUND: The introduction of multiparameter MRI and novel biomarkers has greatly improved the prediction of clinically significant prostate cancer (csPCa). However, decision-making regarding prostate biopsy and prebiopsy examinations is still difficult. We aimed to establish a quick and economic tool to improve the detection of csPCa based on routinely performed clinical examinations through an automated machine learning platform (AutoML). METHODS: This study included a multicenter retrospective cohort and two prospective cohorts with 4747 cases from 9 hospitals across China. The multimodal data, including demographics, clinical characteristics, laboratory tests, and ultrasound reports, of consecutive participants were retrieved using extract-transform-load tools. AutoML was applied to explore potential data processing patterns and the most suitable algorithm to build the Prostate Cancer Artificial Intelligence Diagnostic System (PCAIDS). The diagnostic performance was determined by the receiver operating characteristic curve (ROC) for discriminating csPCa from insignificant prostate cancer (PCa) and benign disease. The clinical utility was evaluated by decision curve analysis (DCA) and waterfall plots. RESULTS: The random forest algorithm was applied in the feature selection, and the AutoML algorithm was applied for model establishment. The area under the curve (AUC) value in identifying csPCa was 0.853 in the training cohort, 0.820 in the validation cohort, 0.807 in the Changhai prospective cohort, and 0.850 in the Zhongda prospective cohort. DCA showed that the PCAIDS was superior to PSA or fPSA/tPSA for diagnosing csPCa with a higher net benefit for all threshold probabilities in all cohorts. Setting a fixed sensitivity of 95%, a total of 32.2%, 17.6%, and 26.3% of unnecessary biopsies could be avoided with less than 5% of csPCa missed in the validation cohort, Changhai and Zhongda prospective cohorts, respectively. CONCLUSIONS: The PCAIDS was an effective tool to inform decision-making regarding the need for prostate biopsy and prebiopsy examinations such as mpMRI. Further prospective and international studies are warranted to validate the findings of this study. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2100048428. Registered on 06 July 2021.


Assuntos
Inteligência Artificial , Neoplasias da Próstata , Masculino , Humanos , Estudos Retrospectivos , Algoritmos , Aprendizado de Máquina
8.
Front Immunol ; 14: 1181620, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143650

RESUMO

The treatment of B-cell acute lymphoblastic leukemia (B-ALL) with central nervous system (CNS) involvement poses a significant clinical challenge because most chemotherapeutic agents exhibit weak permeability to the blood-brain barrier (BBB). In addition, current anti-CNS leukemia treatments often bring short or long-term complications. Immunotherapy including chimeric antigen T-cell therapy and bispecific antibody have shown profound treatment responses in relapsed/refractory B-ALL. However, there is a lack of data on the efficacy of bispecific antibody in treating B-ALL with CNS involvement. Here, we report two ALL patients with CNS leukemia who received blinatumomab. Case 1 was diagnosed with chronic myeloid leukemia in lymphoid blast phase. The patient developed CNS leukemia and bone marrow relapse during the treatment with dasatinib. Case 2 was diagnosed with B-ALL and suffered early hematologic relapse and cerebral parenchyma involvement. After treatment with one cycle of blinatumomab, both patients achieved complete remission in the bone marrow and CNS. Furthermore, this is the first report on the efficacy of blinatumomab in treating CNS leukemia with both of the cerebral spinal fluid and the cerebral parenchymal involvement. Our results suggest that blinatumomab might be a potential option for the treatment of CNS leukemia.


Assuntos
Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Antineoplásicos/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Recidiva , Sistema Nervoso Central
10.
Blood Adv ; 7(17): 4913-4925, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36897251

RESUMO

We conducted a single-arm, open-label, single-center phase 1 study to assess the safety and efficacy of multicycle-sequential anti-CD19 chimeric antigen receptor (CAR) T-cell therapy in combination with autologous CD19+ feeding T cells (FTCs) and tyrosine kinase inhibitor (TKI) as consolidation therapy in patients under the age of 65 years with de novo Ph-positive CD19+ B-cell acute lymphoblastic leukemia. Participants were given induction chemotherapy as well as systemic chemotherapy with TKI. Afterward, they received a single cycle of CD19 CAR T-cell infusion and another 3 cycles of CD19 CAR T-cell and CD19+ FTC infusions, followed by TKI as consolidation therapy. CD19+ FTCs were given at 3 different doses. The phase 1 results of the first 15 patients, including 2 withdrawals, are presented. The most common adverse events were cytopenia (13/13) and hypogammaglobinemia (12/13). There was no incidence of cytokine release syndrome above grade 2 or immune effector cell-associated neurotoxicity syndrome or grade 4 nonhematological toxicities. All 13 patients achieved complete remission, including 12 patients with a complete molecular response (CMR) at the data cutoff. The relapse-free survival was 84%, and the overall survival was 83% with a median follow-up of 27 months. The total number of CD19-expressing cells decreased with an increasing CMR rate. CD19 CAR T cells survived for up to 40 months, whereas CD19+ FTCs vanished in 8 patients 3 months after the last infusion. These findings could form the basis for the development of an allo-HSCT-free consolidation paradigm. This trial was registered at www.clinicaltrials.gov as #NCT03984968.


Assuntos
Antígenos CD19 , Imunoterapia Adotiva , Linfoma de Células B , Síndromes Neurotóxicas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Idoso , Humanos , Antígenos CD19/imunologia , Antígenos CD19/uso terapêutico , Quimioterapia de Consolidação , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Linfócitos T , Imunoterapia Adotiva/métodos
11.
Talanta ; 253: 123896, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36103749

RESUMO

Tinuvin 622, an oligomeric light stabilizer, is widely used in plastics to reduce light and heat induced degradation and extend their service life, therefore its detection is of great importance for quality control of plastic products. However, the classical analytical methods of Tinuvin 622, such as chromatography and mass spectrometry, are difficult to achieve direct qualitative and quantitative analysis, and simultaneously to obtain the molecular weight and molecular weight distribution information. Herein, we propose for the first time the combination of gel permeation chromatography with multi-angle laser light scattering as a simple and direct method to detect Tinuvin 622 in polymers and simultaneously to obtain its molecular weight distribution information. The linearity of the method was good in the concentration range of 0.1-5.0 mg/mL Tinuvin 622 with correlation coefficient (R2 = 0.9999), and the recoveries of Tinuvin 622 at three addition levels ranged from 94.0% to 98.7%, with relative standard deviations of no more than 1.73%. The proposed method has been successfully used to detect Tinuvin 622 in actual samples of polymer additives. Compared with existing analytical methods, Tinuvin 622 has a single peak shape in our method, which is easy to identify and quantify accurately; more importantly, our method can simultaneously characterize the molecular weight and molecular weight distribution of Tinuvin 622, which makes up for the shortcomings of other approaches and provides a new tool for quality monitoring of polymer additives.


Assuntos
Lasers , Polímeros , Cromatografia em Gel
12.
Angew Chem Int Ed Engl ; 61(40): e202210097, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-35981229

RESUMO

The Fano resonance in single-molecule junctions could be created by interaction with discrete and continuous molecular orbitals and enables effective electron transport modulation between constructive and destructive interference within a small energy range. However, direct observation of Fano resonance remains unexplored because of the disappearance of discrete orbitals by molecule-electrode coupling. We demonstrated the room-temperature observation of Fano resonance from electrochemical gated single-molecule conductance and current-voltage measurements of a para-carbazole anion junction. Theoretical calculations reveal that the negative charge on the nitrogen atom induces a localized HOMO on the molecular center, creating Fano resonance by interfering with the delocalized LUMO on the molecular backbone. Our findings demonstrate that the Fano resonance in electron transport through single-molecule junctions opens pathways for designs of interference-based electronic devices.

13.
Small ; 18(20): e2200361, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35481610

RESUMO

Investigating the correlations of electron transport between multiple channels shows vital promises for the design of molecule-scale circuits with logic operations. To control the electron transport through multiple channels, the modulation of electronegativity shows an effective frontier orbit control method with high universality to explore the interactions between transport channels. Here, two series of compounds with a single nitrogenous conductive channel (Sg) and dual-channels (Db) are designed to explore the influence of electronegativity on electron tunneling transport. Single-molecule conductance measured via the scanning tunneling microscope break junction technique (STM-BJ) reveals that the conductance of Db series is significantly suppressed as the electronegativity of nitrogen becomes negative, while the suppression on Sg is less obvious. Theoretical calculations confirm that the effect of electronegativity extends to a dispersive range of molecular frameworks owing to the delocalized orbital distribution from the dual-channel structure, resulting in a more significant conductance suppression effect than that on the single-channel. This study provides the experimental and theoretical potentials of electronegativity gating for molecular circuits.


Assuntos
Nanotecnologia , Nitrogênio , Condutividade Elétrica , Transporte de Elétrons
14.
Nano Lett ; 21(22): 9729-9735, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34761680

RESUMO

Unveiling the internal dynamics of rotation in molecular machine at single-molecule scale is still a challenge. In this work, three crank-shaped molecules are elaborately designed with the conformational flipping between syn and anti fulfilled by two naphthyl groups rotating freely along 1,3-butadiynyl axis. By investigating the single-molecule conductance using scanning tunnelling microscope break junction (STM-BJ) technique and theoretical simulation, the internal rotation of these crank-shaped molecules is well identified through low and high conductance corresponding to syn- and anti-conformations. As demonstrated by theoretically computational study, the orbital energy changes with the conformational flipping and influences the intraorbital quantum interference, thus eventually modulating the single-molecule conductance. This work demonstrates single-molecule conductance measurement to be a rational approach for characterizing the internal rotation of molecular machines.


Assuntos
Conformação Molecular , Nanotecnologia , Rotação , Simulação por Computador
15.
Front Oncol ; 11: 726926, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540696

RESUMO

OBJECTIVE: To explore the role of chidamide, decitabine plus priming regimen in the salvage treatment of relapsed/refractory acute myeloid leukemia. METHODS: A clinical trial was conducted in relapsed/refractory acute myeloid leukemia patients using chidamide, decitabine, cytarabine, idarubicin, and granulocyte-colony stimulating factor, termed CDIAG, a double epigenetic priming regimen. RESULTS: Thirty-five patients were recruited. Three patients received 2 treatment cycles. In 32 evaluable patients and 35 treatment courses, the completed remission rate (CRR) was 42.9%. The median OS time was 11.7 months. The median OS times of responders were 18.4 months, while those of nonresponders were 7.4 months (P = 0.015). The presence of RUNX1 mutations was associated with a high CRR but a short 2-year OS (P = 0.023) and PFS (P = 0.018) due to relapse after treatment. The presence of IDH mutations had no effect on the remission rate (80.0% vs. 73.3%), but showed a better OS (2-year OS rate: 100.0% vs. 28.9%). Grade 3/4 nonhematological adverse events included pneumonia, hematosepsis, febrile neutropenia, skin and soft tissue infection and others. CONCLUSION: The double epigenetic priming regimen (CDIAG regimen) showed considerably good antileukemia activity in these patients. Adverse events were acceptable according to previous experience. The study was registered as a clinical trial. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/, identifier:NCT03985007.

16.
Se Pu ; 39(7): 750-757, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34227373

RESUMO

Prednisolone is an adrenal glucocorticoid drug with immunosuppressive, anti-inflammatory, anti-allergic, and antiviral effects that are widely exploited in clinical treatment. The hydrazine residue to prednisolone directly affects medication safety and threatens the patient's health. At present, there are no relevant laws, regulations, and standards to control the residual limit of hydrazine in drugs at home or abroad. Therefore, a simple, rapid, accurate, reliable, sensitive, and selective method is urgently needed for the determination of trace hydrazine in prednisolone. Hydrazine has strong polarity and reductivity, with unstable physical and chemical properties, thus being easily oxidized. In addition, because of the lack of chromophores and low molecular weight, the detection of hydrazine is very difficult. Therefore, a derivative reagent should be introduced to reduce its polarity and generate a derivative product with a high molecular weight as well as stable physical and chemical properties. Acetone, as a common laboratory reagent, is inexpensive and can rapidly react with hydrazine; therefore, it is an ideal derivative reagent for the determination of hydrazine. In this study, a method based on precolumn derivatization with gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) was developed for the determination of hydrazine in prednisolone by optimizing the derivatization reagent, GC and MS conditions, solvent system, and derivatization conditions. Method validation was then carried out using the established method, and the results were satisfactory. In this study, 1 g of prednisolone sample was weighed and placed in a 10 mL centrifuge tube with a plug; then, a methanol-dichloromethane dilution solvent (14∶23, v/v) was added to the scale line, and the sample was vortexed until completely dissolved. About 100 µL of the test solution prepared above was pipetted into the sample vial, followed by the addition of 900 µL acetone. The resulting solution was vortexed and mixed well. The sample was diluted and derivatized simultaneously in acetone solution, acetone/methanol-dichloromethane dilution solvent (9∶1, v/v), and then detected and analyzed by GC-MS/MS. In this study, the derivatization reaction between hydrazine and acetone did not require the addition of acetic acid and ultrasound conditions, or the use of other reagents for the extraction operation. The reaction was instantaneous, and rapid determination of hydrazine in prednisolone could be achieved. The standard curve was obtained with a good correlation coefficient (r2=0.9999) in the range 1-12 µg/L. The limits of detection and quantitation were 0.03 mg/kg and 0.10 mg/kg, respectively. The relative standard deviation (RSD) of injection precision was 1.10%. The recoveries and repeatability were good; the recoveries of low-, medium-, and high-concentration spiked samples were 96.15%-96.46% at spiked concentrations of 1, 6, and 12 µg/L, respectively, and the corresponding RSDs were 1.77%-2.12%. The intermediate precision was good, and the RSD of the determination results obtained on the same instrument by different laboratory technicians at different times was 1.77%. The durability was good, and the degree of influence of the detection results was studied by changing the chromatographic conditions. Under the original condition or conditions with initial column temperature ±5 ℃, heating rate ±2 ℃/min, or column flow rate ±0.1 mL/min, the hydrazine content in the sample solution at a spiked concentration of 6 µg/L was detected, and the RSD of the detection results was 2.58%. The established method was applied to detect hydrazine in a prednisolone standard substance procured from the market and nine batches of prednisolone samples provided by a pharmaceutical company. No hydrazine was detected in any of these samples. The established method is simple, reliable, highly sensitive, and highly selective, and it can be applied for the detection of hydrazine in prednisolone.


Assuntos
Contaminação de Medicamentos , Hidrazinas , Prednisolona , Cromatografia Gasosa-Espectrometria de Massas , Hidrazinas/análise , Prednisolona/análise , Solventes , Espectrometria de Massas em Tandem
19.
Commun Biol ; 3(1): 612, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097765

RESUMO

Myostatin (MSTN), associated with the "double muscling" phenotype, affects muscle growth and fat deposition in animals, whereas how MSTN affects adipogenesis remains to be discovered. Here we show that MSTN can act through the MEF2C/miR222/SCD5 cascade to regulate fatty acid metabolism. We generated MSTN-knockout (KO) cloned Meishan pigs, which exhibits typical double muscling trait. We then sequenced transcriptome of subcutaneous fat tissues of wild-type (WT) and MSTN-KO pigs, and intersected the differentially expressed mRNAs and miRNAs to predict that stearoyl-CoA desaturase 5 (SCD5) is targeted by miR222. Transcription factor binding prediction showed that myogenic transcription factor 2C (MEF2C) potentially binds to the miR222 promoter. We hypothesized that MSTN-KO upregulates MEF2C and consequently increases the miR222 expression, which in turn targets SCD5 to suppress its translation. Biochemical, molecular and cellular experiments verified the existence of the cascade. This novel molecular pathway sheds light on new targets for genetic improvements in pigs.


Assuntos
Ácidos Graxos , Fatores de Transcrição MEF2/metabolismo , MicroRNAs/metabolismo , Miostatina , Estearoil-CoA Dessaturase/metabolismo , Animais , Ácidos Graxos/genética , Ácidos Graxos/metabolismo , Edição de Genes , Técnicas de Inativação de Genes , Fatores de Transcrição MEF2/genética , MicroRNAs/genética , Miostatina/genética , Miostatina/metabolismo , Regiões Promotoras Genéticas/genética , Estearoil-CoA Dessaturase/genética , Gordura Subcutânea/metabolismo , Sus scrofa , Suínos , Transcriptoma/genética
20.
Cancer Cell Int ; 20: 87, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32206038

RESUMO

BACKGROUND: LncRNA NEAT1 has been identified as a tumour driver in many human cancers. However, the underlying mechanism of lncRNA NEAT1 in diffuse large B-cell lymphoma (DLBCL) progression is unclear. METHODS: The expression levels of NEAT1, GLI1 and miR-34b-5p were detected by RT-qPCR and Western blotting in DLBCL tissues and cell lines. MTT and colony formation assays were performed to examine cell proliferation, while annexin-V staining and TUNEL assays were performed to measure cell apoptosis. The effect of NEAT1, GLI1 and miR-34b-5p on cell cycle-associated proteins was evaluated by Western blotting. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were employed to investigate the interaction between NEAT1 and miR-34b-5p or GLI1 and miR-34b-5p. Moreover, chromatin immunoprecipitation (ChIP) was performed to demonstrate the interaction between MYC and NEAT1. RESULTS: NEAT1 and GLI1 were upregulated while miR-34b-5p was downregulated in DLBCL tissues and cell lines compared to normal controls. Knockdown of NEAT1 or overexpression of miR-34b-5p inhibited cell proliferation but promoted cell apoptosis. Overexpression of NEAT1 reversed GLI1-knockdown induced attenuation of cell proliferation. In other words, NEAT1 acted as a competing endogenous RNA (ceRNA), regulating the miR-34b-5p-GLI1 axis, further affecting the proliferation of DLBCL. Moreover, MYC modulated NEAT1 transcription by directly binding to the NEAT1 promoter. CONCLUSION: We revealed that MYC-regulated NEAT1 promoted DLBCL proliferation via the miR-34b-5p-GLI1 pathway, which could provide a novel therapeutic target for DLBCL.

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