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1.
Blood ; 139(26): 3752-3770, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35439288

RESUMO

Differentiation blockade is a hallmark of acute myeloid leukemia (AML). A strategy to overcome such a blockade is a promising approach against the disease. The lack of understanding of the underlying mechanisms hampers development of such strategies. Dysregulated ribonucleotide reductase (RNR) is considered a druggable target in proliferative cancers susceptible to deoxynucleoside triphosphate (dNTP) depletion. Herein, we report an unanticipated discovery that hyperactivating RNR enables differentiation and decreases leukemia cell growth. We integrate pharmacogenomics and metabolomics analyses to identify that pharmacologically (eg, nelarabine) or genetically upregulating RNR subunit M2 (RRM2) creates a dNTP pool imbalance and overcomes differentiation arrest. Moreover, R-loop-mediated DNA replication stress signaling is responsible for RRM2 activation by nelarabine treatment. Further aggravating dNTP imbalance by depleting the dNTP hydrolase SAM domain and HD domain-containing protein 1 (SAMHD1) enhances ablation of leukemia stem cells by RRM2 hyperactivation. Mechanistically, excessive activation of extracellular signal-regulated kinase (ERK) signaling downstream of the imbalance contributes to cellular outcomes of RNR hyperactivation. A CRISPR screen identifies a synthetic lethal interaction between loss of DUSP6, an ERK-negative regulator, and nelarabine treatment. These data demonstrate that dNTP homeostasis governs leukemia maintenance, and a combination of DUSP inhibition and nelarabine represents a therapeutic strategy.


Assuntos
Leucemia Mieloide Aguda , Ribonucleotídeo Redutases , Replicação do DNA , Homeostase , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Polifosfatos , Ribonucleotídeo Redutases/genética , Ribonucleotídeo Redutases/metabolismo
2.
Opt Express ; 32(8): 14054-14066, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859361

RESUMO

We present a laser-driven interferometric fiber optic gyroscope (IFOG) with polarization self-compensation to achieve high scale-factor stability, sensitivity, and long-term stability. Coherent light with 200kHz linewidth is employed to keep the scale factor stable. The optical scheme ensures polarization reciprocity as well as the optimal working point for good sensitivity. Furthermore, a hybrid machine learning loop (MLL) method, combining the advantages of PID fast response and artificial neural network (ANN) dynamic search, can control a liquid crystal rotator (LCR) to dynamically compensate for slow drift induced by polarization coupling. In open environment, when the sensitivity is 0.005 ∘/h, the bias instability (BI) is significantly optimized from 0.6723°/h at 60s (PID) to 0.3869°/h at 200s (MLL), which is close to the Sagnac interferometric limit (SIL). Such IFOG can meet the real-time and robust requirements for inertial navigation systems in long-term measurement.

3.
Opt Express ; 32(7): 12982-12991, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571104

RESUMO

Quantum dense metrology (QDM) performs high-precision measurements by a two-mode entangled state created by an optical parametric amplifier (PA), where one mode is a meter beam and the other is a reference beam. In practical applications, the photon losses of meter beam are unavoidable, resulting in a degradation of the sensitivity. Here, we employ coherent feedback that feeds the reference beam back into the PA by a beam splitter to enhance the sensitivity in a lossy environment. The results show that the sensitivity is enhanced significantly by adjusting the splitting ratio of the beam splitter. This method may find its potential applications in QDM. Furthermore, such a strategy that two non-commuting observables are simultaneous measurements could provide a new way to individually control the noise-induced random drift in phase or amplitude of the light field, which would be significant for stabilizing the system and long-term precision measurement.

4.
J Neuroeng Rehabil ; 21(1): 37, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38504351

RESUMO

BACKGROUND: Children with unilateral cerebral palsy (UCP) are encouraged to participate in the regular school curriculum. However, even when using the less-affected hand for handwriting, children with UCP still experience handwriting difficulties. Visual-motor integration (VMI) is a predictor of handwriting quality. Investigating VMI in children with UCP is important but still lacking. Conventional paper-based VMI assessments is subjective and use all-or-nothing scoring procedures, which may compromise the fidelity of VMI assessments. Moreover, identifying important shapes that are predictive of VMI performance might benefit clinical decision-making because different geometric shapes represent different developmental stepping stones of VMI. Therefore, a new computer-aided measure of VMI (the CAM-VMI) was developed to investigate VMI performance in children with UCP and to identify shapes important for predicting their VMI performance. METHODS: Twenty-eight children with UCP and 28 typically-developing (TD) children were recruited. All participants were instructed to complete the CAM-VMI and Beery-Buktenica Developmental Test of Visual-Motor Integration (Beery-VMI). The test items of the CAM-VMI consisted of nine simple geometric shapes related to writing readiness. Two scores of the CAM-VMI, namely, Error and Effort, were obtained by image registration technique. The performances on the Beery-VMI and the CAM-VMI of children with UCP and TD children were compared by independent t-test. A series of stepwise regression analyses were used to identify shapes important for predicting VMI performance in children with UCP. RESULTS: Significant group differences were found in both the CAM-VMI and the Beery-VMI results. Furthermore, Error was identified as a significant aspect for predicting VMI performance in children with UCP. Specifically, the square item was the only significant predictor of VMI performance in children with UCP. CONCLUSIONS: This study was a large-scale study that provided direct evidence of impaired VMI in school-aged children with UCP. Even when using the less-affected hand, children with UCP could not copy the geometric shapes as well as TD children did. The copied products of children with UCP demonstrated poor constructional accuracy and inappropriate alignment. Furthermore, the predictive model suggested that the constructional accuracy of a copied square is an important predictor of VMI performance in children with UCP.


Assuntos
Paralisia Cerebral , Desenvolvimento Infantil , Criança , Humanos , Desempenho Psicomotor , Computadores , Mãos
5.
Phys Rev Lett ; 130(7): 073601, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36867793

RESUMO

Interferometers are crucial for precision measurements, including gravitational waves, laser ranging, radar, and imaging. The phase sensitivity, the core parameter, can be quantum-enhanced to break the standard quantum limit (SQL) using quantum states. However, quantum states are highly fragile and quickly degrade with losses. We design and demonstrate a quantum interferometer utilizing a beam splitter with a variable splitting ratio to protect the quantum resource against environmental impacts. The optimal phase sensitivity can reach the quantum Cramér-Rao bound of the system. This quantum interferometer can greatly reduce the quantum source requirements in quantum measurements. In theory, with a 66.6% loss rate, the sensitivity can break the SQL using only a 6.0 dB squeezed quantum resource with the current interferometer rather than a 24 dB squeezed quantum resource with a conventional squeezing-vacuum-injected Mach-Zehnder interferometer. In experiments, when using a 2.0 dB squeezed vacuum state, the sensitivity enhancement remains at ∼1.6 dB via optimizing the first splitting ratio when the loss rate changes from 0% to 90%, indicating that the quantum resource is excellently protected with the existence of losses in practical applications. This strategy could open a way to retain quantum advantages for quantum information processing and quantum precision measurement in lossy environments.

6.
Phys Rev Lett ; 131(15): 150804, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897768

RESUMO

A quantum memory with the performances of low noise, high efficiency, and high bandwidth is of crucial importance for developing practical quantum information technologies. However, the excess noises generated during the highly efficient processing of quantum information inevitably destroy quantum state. Here, we present a quantum memory with built-in excess-noise eraser by integrating a photon-correlated quantum interferometry in quantum memory, where the memory efficiency can be enhanced and the excess noises can be suppressed to the vacuum level via destructive interference. This quantum memory is demonstrated in a rubidium vapor cell with a 10-ns-long photonics signal. We observe ∼80% noise suppression, the write-in efficiency enhancement from 87% to 96.2% without and with interferometry, and the corresponding memory efficiency excluding the noises from 70% to 77%. The fidelity is 93.7% at the single-photon level, significantly exceeding the no-cloning limit. Such interferometry-integrated quantum memory, the first expansion of quantum interference techniques to quantum information processing, simultaneously enables low noise, high bandwidth, high efficiency, and easy operation.

7.
J Biomed Sci ; 30(1): 47, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37380972

RESUMO

BACKGROUND: A large proportion of the patients with cancer do not respond to immunotherapies. Recent studies suggested an important role for tumor-infiltrating cytotoxic T lymphocytes (CTL) in enhancing response to immunotherapy. Here, we aim to identify gene that induce proliferative and cytotoxic states of CD8+ T cells, and to investigate its effect on CAR-T cells against colorectal cancer. METHODS: Correlation between the expression of IFI35 with the activation and cytotoxicity of CD8+ T cells was assessed with TCGA and proteomic databases. Then we constructed murine colon cancer cells over-expressing IFI35 and tested their effect on anti-tumor immunity in both immunodeficient and immunocompetent mouse models. Flow cytometry and immunohistochemistry were performed to assess the immune microenvironment. Western blot analysis was used to identify the potential down-stream signaling pathway regulated by IFI35. We further investigated the efficacy of the rhIFI35 protein in combination with immunotherapeutic treatment. RESULTS: The transcriptional and proteomic analysis of the activation and cytotoxicity of CD8+ T cells in human cancer samples demonstrated that IFI35 expression is correlated with increased CD8+ T cell infiltration and predicted a better outcome in colorectal cancer. The number and cytotoxicity of CD8+ T cells were significantly increased in IFI35-overexpressing tumors. Mechanistically, we identified that the IFNγ-STAT1-IRF7 axis stimulated IFI35 expression, and that IFI35-mediated regulation of CD8+ T cell proliferation and cytotoxicity was dependent on PI3K/AKT/mTOR signaling pathway in vitro. Furthermore, IFI35 protein enhanced the efficacy of CAR-T cells against colorectal cancer cells. CONCLUSION: Our findings identify IFI35 as a new biomarker that can enhance the proliferation and function of CD8+ T cells, as well as increase the efficacy of CAR-T cells against colorectal cancer cells.


Assuntos
Antineoplásicos , Neoplasias do Colo , Humanos , Animais , Camundongos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt/genética , Linfócitos T CD8-Positivos , Proteômica , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Microambiente Tumoral
8.
Am J Occup Ther ; 77(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36730106

RESUMO

IMPORTANCE: Handwriting legibility is the main criterion for determining whether a child has handwriting difficulties. A comprehensive assessment of handwriting legibility with sound psychometrics is essential to timely identification of handwriting difficulties and outcome measurement after handwriting interventions. OBJECTIVE: To evaluate the psychometrics of the Computer-Aided Measure of Chinese Handwriting Legibility (CAM-CHL) and to investigate Chinese handwriting legibility in school-age children using the CAM-CHL. DESIGN: Cross-sectional, repeated observation, test-retest. SETTING: Elementary schools in Taiwan. PARTICIPANTS: We recruited 25 lower-grade children for the examination of test-retest reliability, 75 children from all grade levels, and 10 senior schoolteachers for the examination of the CAM-CHL's convergent validity and the investigation of handwriting legibility. OUTCOMES AND MEASURES: Children were asked to copy a set of Chinese characters as legibly as possible. We used the CAM-CHL to assess handwriting legibility in four domains: Size, Orientation, Position, and Deformation. The schoolteachers were asked to subjectively assess the handwriting legibility using a 3-point Likert-type scale. RESULTS: The CAM-CHL demonstrated good to excellent test-retest reliability and acceptable random measurement error in all legibility domains. The CAM-CHL had fair to moderate convergent validity with schoolteachers' perceptions. Additionally, upper-grade children had better handwriting legibility in the Size and Position domains than lower-grade children. CONCLUSIONS AND RELEVANCE: The CAM-CHL, a comprehensive and objective method of assessing Chinese handwriting legibility, has sound reliability and acceptable validity, suggesting its potential as an outcome measure for school-age children. What This Article Adds: The CAM-CHL can be used in comprehensive evaluations of Chinese handwriting legibility in school-age children. The CAM-CHL has acceptable psychometrics for use as an outcome measure.


Assuntos
Computadores , Escrita Manual , Humanos , Criança , Psicometria , Reprodutibilidade dos Testes , Estudos Transversais
9.
J Environ Sci (China) ; 116: 151-162, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35219414

RESUMO

High-resolution vehicular emissions inventories are important for managing vehicular pollution and improving urban air quality. This study developed a vehicular emission inventory with high spatio-temporal resolution in the main urban area of Chongqing, based on real-time traffic data from 820 RFID detectors covering 454 roads, and the differences in spatio-temporal emission characteristics between inner and outer districts were analysed. The result showed that the daily vehicular emission intensities of CO, hydrocarbons, PM2.5, PM10, and NOx were 30.24, 3.83, 0.18, 0.20, and 8.65 kg/km per day, respectively, in the study area during 2018. The pollutants emission intensities in inner district were higher than those in outer district. Light passenger cars (LPCs) were the main contributors of all-day CO emissions in the inner and outer districts, from which the contributors of NOx emissions were different. Diesel and natural gas buses were major contributors of daytime NOx emissions in inner districts, accounting for 40.40%, but buses and heavy duty trucks (HDTs) were major contributors in outer districts. At nighttime, due to the lifting of truck restrictions and suspension of buses, HDTs become the main NOx contributor in both inner and outer districts, and its three NOx emission peak hours were found, which are different to the peak hours of total NOx emission by all vehicles. Unlike most other cities, bridges and connecting channels are always emission hotspots due to long-time traffic congestion. This knowledge will help fully understand vehicular emissions characteristics and is useful for policymakers to design precise prevention and control measures.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Dispositivo de Identificação por Radiofrequência , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental , Veículos Automotores , Emissões de Veículos/análise
10.
Biochem Biophys Res Commun ; 566: 67-74, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34119827

RESUMO

Our previous studies have initially identified HJURP, which encodes a Holliday junction recognizing protein, as a hepatocellular carcinoma (HCC) susceptibility gene. In this report, we showed that the HJURP is highly expressed in HCC tissues compared to adjacent normal tissues. Overexpression of HJURP in HCC tissues is mainly due to the hypomethylation of HJURP promoter region. Clinically, high expression of HJURP is significantly associated with poor overall survival and disease-free survival of patients with HCC, as well as in multiple other types of cancer. Gain- and loss-of functional studies demonstrated that HJURP promotes HCC cell proliferation, clone formation, migration and invasion. Additionally, HJURP enhances HCC tumorigenesis via reducing G0/G1 arrest and apoptosis. Mechanistically, by gene set enrichment analysis (GSEA) analysis, HJURP was identified as a modulator involved in CENPA-mediated centromere maintenance. Our results provide evidence of HJURP as an important oncogene that promotes HCC progression, and the HJURP pathway may be a potential target for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Metilação de DNA , Proteínas de Ligação a DNA/genética , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Prognóstico , Regulação para Cima
11.
Sens Actuators B Chem ; 331: 129415, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33519091

RESUMO

The coronavirus disease 2019 (COVID-19) epidemic continues to ravage the world. In epidemic control, dealing with a large number of samples is a huge challenge. In this study, a point-of-care test (POCT) system was successfully developed and applied for rapid and accurate detection of immunoglobulin-G and -M against nucleocapsid protein (anti-N IgG/IgM) and receptor-binding domain in spike glycoprotein (anti-S-RBD IgG/IgM) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Any one of the IgG/IgM found in a sample was identified as positive. The POCT system contains colloidal gold-based lateral flow immunoassay test strips, homemade portable reader, and certified reference materials, which detected anti-N and anti-S-RBD IgG/IgM objectively in serum within 15 min. Receiver operating characteristic curve analysis was used to determine the optimal cutoff values, sensitivity, and specificity. It exhibited equal to or better performances than four approved commercial kits. Results of the system and chemiluminescence immunoassay kit detecting 108 suspicious samples had high consistency with kappa coefficient at 0.804 (P < 0.001). Besides, the levels and alterations of the IgG/IgM in an inpatient were primarily investigated by the POCT system. Those results suggested the POCT system possess the potential to contribute to rapid and accurate serological diagnosis and epidemiological survey of COVID-19.

12.
Mediators Inflamm ; 2021: 6104529, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34456629

RESUMO

It has been considered that glucose fluctuation (GF) plays a role in renal injury and is related to diabetic nephropathy (DN) development. But the mechanism is still unclear. Aerobic glycolysis has become a topical issue in DN in recent years. There is an internal connection between GF, aerobic glycolysis, and DN. Curcumin (Cur) is a principal curcuminoid of turmeric and possesses specific protective properties in kidney functions. Cur also participates in the regulation of aerobic glycolysis switch. In this study, we first measured the levels of aerobic glycolysis and evaluated Cur's inhibitory ability in a cell model of HEK-293 under the condition of oscillating high glucose. The results indicated that GF exacerbated inflammation injury, oxidative stress, and apoptosis in HEK-293 cell, while Cur alleviated this cytotoxicity induced by GF. We found that GF increased aerobic glycolysis in HEK-293 cells and Cur presented a dose-dependent weakening effect to this exacerbation. Next, we built a panel of 17 miRNAs and 8 lncRNAs that were previously reported to mediate the Warburg effect. Our RT-qPCR results indicated that GF reduced the miR-489 content in the HEK-293 cell model and Cur could prevent this downregulation. Then, we planned to explore the character of miR-489 in Cur-triggered attenuation of the Warburg effect under GF condition. Our findings presented that Cur prevented GF-triggered aerobic glycolysis by upregulating miR-489 in HEK-293 cells. Next, we choose the miR-489/LDHA axis for further investigation. We confirmed that Cur prevented GF-triggered aerobic glycolysis via the miR-489/LDHA axis in HEK-293 cells. In conclusion, this study presented that Cur prevented GF-triggered renal injury by restraining aerobic glycolysis via the miR-489/LDHA axis in the HEK-293 cell model.


Assuntos
Curcumina , MicroRNAs , Proliferação de Células , Curcumina/farmacologia , Regulação Neoplásica da Expressão Gênica , Glucose/metabolismo , Glucose/toxicidade , Glicólise , Células HEK293 , Humanos , Rim/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo
13.
Zhongguo Zhong Yao Za Zhi ; 45(6): 1433-1439, 2020 Mar.
Artigo em Zh | MEDLINE | ID: mdl-32281358

RESUMO

The aim of this study was to observe the protective effect of water extract from Sabia parviflora on mice with acute liver injury induced by acetaminophen, and investigate its possible mechanism. Fifty-eight Kunming mice were divided into 6 groups, 8 in the normal group, 10 in the model group, 10 in the biphenyl diester group, and 10 each in the low, medium and high dose groups. After adaptive feeding for one week, the mice in normal group were intragastrically administered with an equal volume of 0.5% sodium carboxymethylcellulose sodium(CMC-Na), and the mice in other groups were intragastrically administered with corresponding drugs at 20 mL·kg~(-1) once a day. Then acetaminophen(200 mg·kg~(-1)) was administered after the above drug administration except the normal group. The behavior and signs of the experimental animals were observed every day and the samples were taken for experiments on the next day of the final administration. The liver mass and mass index were calculated. The blood was collected from the abdominal aorta and centrifuged to obtain the serum for detecting aspartate aminotransferase(AST) activity and alanine aminotransferase(ALT) activity. The liver tissue homogenate was used to detect superoxide dismutase(SOD) activity, glutathione(glutathione, r-glutamyl cysteingl+glycine, GSH) activity and malondialdehyde(MDA) content. Liver tissue was analyzed for histological analysis. The results showed that S. parviflora could alleviate the lipid peroxidation damage in the liver caused by acetaminophen, reduce the ALT and AST activities in serum, increase the levels of SOD and GSH in liver tissue, decrease the content of MDA in liver tissue, and inhibit the apoptosis. S. parviflora could also improve the live histopathological profile, protect liver cells and restore liver function. Among them, the high dose had the most significant effect and showed dose-effect relationship. This study indicated that S. parviflora had a significant protective effect on acetaminophen-induced liver injury in mice, and its mechanism may be related to its anti-oxidation effect and inhi-bitory effect on apoptosis.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Fígado/enzimologia , Malondialdeído/análise , Camundongos , Estresse Oxidativo , Superóxido Dismutase/metabolismo
14.
J Cell Biochem ; 119(7): 5082-5103, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28681936

RESUMO

This network meta-analysis is adopted in order to compare the toxicity of different chemotherapy regimens in the treatment of advanced/metastatic pancreatic cancer (PC). Randomized controlled trials (RCTs) about different chemotherapy regimens for advanced/metastatic PC were included in this network meta-analysis using Cochrane Library and PubMed electronic databases. The network meta-analysis was performed to combine direct and indirect evidence in order to calculate the odd ratios (OR) and draw a surface under the cumulative ranking (SUCRA) curve. A total of 19 RCTs were enrolled in this network meta-analysis including 12 chemotherapy regimens (Gemcitabine, Gemcitabine + S-1 [tegafur], Gemcitabine + nab-paclitaxel, Gemcitabine + Capecitabine, Gemcitabine + Cisplatin, FOLFIRINOX [oxaliplatin + irinotecan + fluorouracil + leucovorin], Gemcitabine + oxaliplatin, Gemcitabine + irinotecan, Gemcitabine + Exatecan, Gemcitabine + pemetrexed, Gemcitabine + 5-FU, S-1). The incidence of anemia of Gemcitabine + Capecitabine regimen was higher compared with Gemcitabine regimen, Gemcitabine + pemetrexed regimen exhibited the highest incidence rates of anemia and neutropenia; while Gemcitabine + S-1, Gemcitabine + Cisplatin and FOLFIRINOX regimens exhibited the highest incidence rates of neutropenia. However, S-1 regimen exhibited lower incidence rates of leukopenia and thrombocytopenia. Moreover, the incidence rates of nausea/vomiting and rash of Gemcitabine + S-1 regimen were higher compared with Gemcitabine regimen, while Gemcitabine + Cisplatin regimen had the highest incidence rate of nausea/vomiting. This study demonstrated that the hematologic toxicity of S-1 regimen was the lowest, while Gemcitabine regimen exhibited the lowest incidence rate of non-hematologic toxicity, providing guidance for the treatment of advanced/metastatic PC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Fluoruracila/uso terapêutico , Humanos , Irinotecano/uso terapêutico , Leucovorina/uso terapêutico , Metanálise em Rede , Oxaliplatina/uso terapêutico , Gencitabina
15.
Langmuir ; 34(26): 7663-7672, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29871483

RESUMO

In this study, an interface coassembly strategy is employed to rationally synthesize a yolk-shell CuO/silicalite-1@void@mSiO2 composite consisting of silicalite-1 supported CuO nanoparticles confined in the hollow space of mesoporous silica, and the obtained composite materials were used as a novel nonenzymatic biosensor for highly sensitive and selective detecting glucose with excellent anti-interference ability. The synthesis of CuO/silicalite-1@mSiO2 includes four steps: coating silicalite-1 particles with resorcinol-formaldehyde polymer (RF), immobilization of copper species, interface deposition of a mesoporous silica layer, and final calcination in air to decompose RF and form CuO nanoparticles. The unique hierarchical porous structure with mesopores and micropores is beneficial to selectively enrich glucose for fast oxidation into gluconic acid. Besides, the mesopores in the silica shell can effectively inhibit the large interfering substances or biomacromolecules diffusing into the void as well as the loss of CuO nanoparticles. The hollow chamber inside serves as a nanoreactor for glucose oxidation catalyzed by the active CuO nanoparticles, which are spatially accessible for glucose molecules. The nonenzymatic glucose biosensors based on CuO/silicalite-1@mSiO2 materials show excellent electrocatalytic sensing performance with a wide linear range (5-500 µM), high sensitivity (5.5 µA·mM-1·cm-2), low detection limit (0.17 µM), and high selectivity against interfering species. Furthermore, the unique sensors even display a good capability in the determination of glucose in real blood serum samples.


Assuntos
Técnicas Biossensoriais/métodos , Cobre/química , Glucose/análise , Dióxido de Silício/química , Técnicas Biossensoriais/instrumentação , Glicemia/análise , Limite de Detecção , Nanopartículas/química , Oxirredução
16.
Molecules ; 21(3): 232, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26927049

RESUMO

Two new thiazole and thiadiazole alkaloids, penicilliumthiamine A and B (2 and 3), were isolated from the culture broth of Penicillium oxalicum, a fungus found in Acrida cinerea. Their structures were elucidated mainly by spectroscopic analysis, total synthesis and X-ray crystallographic analysis. Biological evaluations indicated that compound 1, 3a and 3 exhibit potent cytotoxicity against different cancer cell lines through inhibiting the phosphorylation of AKT/PKB (Ser 473), one of important cancer drugs target.


Assuntos
Alcaloides/síntese química , Antineoplásicos/síntese química , Citotoxinas/síntese química , Penicillium/química , Tiadiazóis/síntese química , Tiazóis/síntese química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Expressão Gênica , Gafanhotos/microbiologia , Humanos , Estrutura Molecular , Penicillium/isolamento & purificação , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tiadiazóis/isolamento & purificação , Tiadiazóis/farmacologia , Tiazóis/isolamento & purificação , Tiazóis/farmacologia
17.
Zhong Yao Cai ; 39(3): 364-40, 2016 Mar.
Artigo em Zh | MEDLINE | ID: mdl-30091552

RESUMO

Objective: To investigate the estrogenic activities of alcohol extract from Phellinus lonicerinus( AEPL). Methods: Estrogen and anti-estrogen effects were evaluated by cell proliferation experiment in vitro. Through elevating young rat uterine weight, castrated female rats, and adult female rats uterus index serum estradiol( E2) and progesterone( P) were analyzed by enzyme immune methods, and uterine estrogen receptor α( ERα) and estrogen receptor ß( ERß) protein expressions were measeured by immunohistochemisty, and investigated the histopathological of uterus, ovary, and breast of adult female rats. Results: Compared with the control group, AEPL promoted estrogen-sensitive MCF-7 proliferation significantly( P < 0. 05 or P < 0. 01) in the doses of 5 ~ 50 µg / m L in vitro experiment; compared with the E2 control group, it also presented anti-estrogenic effect in E2-induced MCF-7 cells at the doses of 10 ~ 100 µg / m L( P < 0. 05 or P < 0. 01). In the animal experiments, AEPL remarkably increased serum E2 content and promoted growth of uterus in primary female mice at the dose of 300 mg / kg; and raised the serum E2 and P content, alleviated uterine atrophy caused by estrogen deficiency in castrated rats at the dose of 240 mg / kg. In adult female rats, AEPL markedly increased the serum P content at the dose of 120 mg / kg, and also markedly increased the serum E2 content at the dose of 120,240 mg / kg, and regulated the protein expressions of ERαand ERß. AEPL has no effects on histopathological changes of uterus, ovary and mammary gland in rats. Conclusion: AEPL shows estrogenic effects with fewer adverse reaction, which possesses the replacement of estrogen application prospects.


Assuntos
Basidiomycota , Animais , Proliferação de Células , Estradiol , Receptor beta de Estrogênio , Estrogênios , Etanol , Feminino , Humanos , Células MCF-7 , Camundongos , RNA Mensageiro , Ratos , Útero
18.
Zhong Yao Cai ; 38(8): 1680-4, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26983244

RESUMO

OBJECTIVE: To study the effects of ethanol extracts of Phellinus lonicerinus on hepatic stellate cells of fibrosis liver in rats. METHODS: The model rats of hepatic fibrosis were established by intraperitoneally injection of CCl4 olive oil solution at the dose of 2 mL/kg. And then the model rats were administered orally ethanol extract of Phellinus lonicerinus with 1 g/(kg · d) and 0.5 g/( kg · d) for consecutive eight weeks. Serum transforming growth factor-ß1, (TGF-ß1), liver total antioxidant capacity (T-AOC), total superoxide dismutase( T-SOD) activity and the content of malondialdehyde ( MDA) were determined. The α-smooth muscle actin (α-SMA), matrix metalloproteinases-1 (MMP-1) and tissue inhibitor of matrix metalloproteinases-1 (TIMP-1) were determined by immunohistochemical. RESULTS: Compared to the model group, the ethanol extracts of Phellinus lonicerinus decreased the content of serum TGF-ß1 and MDA in liver tissue, as well as increased the activity of T-SOD and the level of T-AOC. Immunohistochemical showed that the ethanol extracts of Phellinus lonicerinus downregulated the expression of α-SMA in liver tissue and the expression of TIMP-1, as well as upregulated the expression of MMP-1. CONCLUSION: The ethanol extracts of Phellinus lonicerinus has good antioxidative activity with application prospects in prevention of hepatic fibrosis. The mechanism may be related to inhibiting the activation of hepatic stellate cells induced by oxidative stress,reducing the TGF-ß1, and cytokines activating the hepatic stellate cells,and upregulating the expression of MMP-1 promoting the collagen degradation.


Assuntos
Basidiomycota/química , Produtos Biológicos/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Cirrose Hepática/tratamento farmacológico , Actinas/metabolismo , Animais , Antioxidantes/metabolismo , Tetracloreto de Carbono , Malondialdeído/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Estresse Oxidativo , Ratos , Superóxido Dismutase/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator de Crescimento Transformador beta1/sangue
19.
Sci Rep ; 14(1): 1787, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245561

RESUMO

In wireless sensor networks (WSNs), protocols with authentication and key agreement functions can enhance the security of the interaction between users and sensor nodes, guaranteeing the security of user access and sensor node information. Existing schemes have various security vulnerabilities and are susceptible to security attacks (e.g., masquerading user, password guessing, internal privilege, and MITT attacks), so they cannot meet the anonymity requirements or achieve forward security. To effectively improve the security performance of WSNs, an elliptic curve cryptography (ECC)-based three-factor authentication and key agreement scheme for WSNs is proposed. The scheme is based on the ECC protocol and combines biometrics, smart card and password authentication technology; uses a challenge/response mechanism to complete the authentication between users, gateways, and sensors; and negotiates a secure session key. The Burrows, Abadi and Needham logic for formal security analysis proves the correctness and security of the scheme, and the informal analysis of multiple known attacks proves that the scheme can resist various attacks and has high security characteristics. The feasibility of the scheme has been analysed and verified with the ProVerif tool. The efficiency analysis results show that the scheme is suitable for resource-constrained WSNs.

20.
Comput Med Imaging Graph ; 115: 102374, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38565036

RESUMO

Medical images play a vital role in medical analysis by providing crucial information about patients' pathological conditions. However, the quality of these images can be compromised by many factors, such as limited resolution of the instruments, artifacts caused by movements, and the complexity of the scanned areas. As a result, low-resolution (LR) images cannot provide sufficient information for diagnosis. To address this issue, researchers have attempted to apply image super-resolution (SR) techniques to restore the high-resolution (HR) images from their LR counterparts. However, these techniques are designed for generic images, and thus suffer from many challenges unique to medical images. An obvious one is the diversity of the scanned objects; for example, the organs, tissues, and vessels typically appear in different sizes and shapes, and are thus hard to restore with standard convolution neural networks (CNNs). In this paper, we develop a dynamic-local learning framework to capture the details of these diverse areas, consisting of deformable convolutions with adjustable kernel shapes. Moreover, the global information between the tissues and organs is vital for medical diagnosis. To preserve global information, we propose pixel-pixel and patch-patch global learning using a non-local mechanism and a vision transformer (ViT), respectively. The result is a novel CNN-ViT neural network with Local-to-Global feature learning for medical image SR, referred to as LGSR, which can accurately restore both local details and global information. We evaluate our method on six public datasets and one large-scale private dataset, which include five different types of medical images (i.e., Ultrasound, OCT, Endoscope, CT, and MRI images). Experiments show that the proposed method achieves superior PSNR/SSIM and visual performance than the state of the arts with competitive computational costs, measured in network parameters, runtime, and FLOPs. What is more, the experiment conducted on OCT image segmentation for the downstream task demonstrates a significantly positive performance effect of LGSR.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Humanos , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Diagnóstico por Imagem/métodos
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