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1.
J Colloid Interface Sci ; 675: 989-998, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39003818

RESUMO

In this paper, a novel, simple and mild soft template assisted strategy and further carbonization approach has been constructed to the size-tunable preparation of porous Cu-N-C/Surfactant catalysts successfully. Note that the pluronic F127 has a significant influence on the synthesis of porous Cu-N-C/F127 with the atomically dispersed Cu-N4 and adjacent Cu atomic clusters (ACs) than other surfactants owing to their particular non-ionic structure. By combining a series of experimental analysis and density functional theory (DFT) calculations, the synergistic effects between the adjacent Cu ACs and atomically dispersed Cu-N4 are favorable for manipulating the binding energy of O2 adsorption and intermediates desorption at the atomic interface of catalysts, resulting in an excellent electrocatalytic ORR performance with a faster kinetics for Cu-N-C/F127 than those of the Cu-N-C, Cu-N-C/CTAB, Cu-N-C/SDS, and comparable with the commercial Pt/C catalyst. This method not only provides a novel approach for synthesizing highly effective copper based single atom catalysts toward ORR, but also offers an in-depth understanding of the synergisms of adjacent ACs on the Cu single atoms (SAs) for highly effective electrocatalytic ORR and Zn-air Battery.

3.
Nat Commun ; 15(1): 5702, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977693

RESUMO

Anion exchange membrane (AEM) water electrolysis employing non-precious metal electrocatalysts is a promising strategy for achieving sustainable hydrogen production. However, it still suffers from many challenges, including sluggish alkaline hydrogen evolution reaction (HER) kinetics, insufficient activity and limited lifetime of non-precious metal electrocatalysts for ampere-level-current-density alkaline HER. Here, we report an efficient alkaline HER strategy at industrial-level current density wherein a flexible WS2 superstructure is designed to serve as the cathode catalyst for AEM water electrolysis. The superstructure features bond-free van der Waals interaction among the low Young's modulus nanosheets to ensure excellent mechanical flexibility, as well as a stepped edge defect structure of nanosheets to realize high catalytic activity and a favorable reaction interface micro-environment. The unique flexible WS2 superstructure can effectively withstand the impact of high-density gas-liquid exchanges and facilitate mass transfer, endowing excellent long-term durability under industrial-scale current density. An AEM electrolyser containing this catalyst at the cathode exhibits a cell voltage of 1.70 V to deliver a constant catalytic current density of 1 A cm-2 over 1000 h with a negligible decay rate of 9.67 µV h-1.

4.
Hortic Res ; 11(7): uhae134, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38974191

RESUMO

Eggplant is one of the most important vegetables worldwide, with some varieties displaying prickles. These prickles, present on the leaves, stems, and fruit calyxes, posing challenges during cultivation, harvesting, and transportation, making them an undesirable agronomic trait. However, the genetic mechanisms underlying prickle morphogenesis in eggplant remain poorly understood, impeding genetic improvements. In this study, genetic analyses revealed that prickle morphogenesis is governed by a single dominant nuclear gene, termed PE (Prickly Eggplant). Subsequent bulk segregant RNA-sequencing (BSR-seq) and linkage analysis preliminarily mapped PE to chromosome 6. This locus was then fine mapped to a 9233 bp interval in a segregating population of 1109 plants, harboring only one candidate gene, SmLOG1, which encodes a LONELY GUY (LOG)-family cytokinin biosynthetic enzyme. Expression analyses via transcriptome and qRT-PCR demonstrate that SmLOG1 is predominantly expressed in immature prickles. CRISPR-Cas9 knockout experiments targeting SmLOG1 in prickly parental line 'PI 381159' abolished prickles across all tissues, confirming its critical role in prickle morphogenesis. Sequence analysis of SmLOG1 pinpointed variations solely within the non-coding region. We developed a cleaved amplified polymorphic sequences (CAPS) marker from a distinct SNP located at -735-bp within the SmLOG1 promoter, finding significant association with prickle variation in 190 eggplant germplasms. These findings enhance our understanding of the molecular mechanisms governing prickle development in eggplant and facilitate the use of marker-assisted selection (MAS) for breeding prickleless cultivars.

5.
Proc Natl Acad Sci U S A ; 121(28): e2403143121, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38959041

RESUMO

Currently, the nanofluidic synapse can only perform basic neuromorphic pulse patterns. One immediate problem that needs to be addressed to further its capability of brain-like computing is the realization of a nanofluidic spiking device. Here, we report the use of a poly(3,4-ethylenedioxythiophene) polystyrene sulfonate membrane to achieve bionic ionic current-induced spiking. In addition to the simulation of various electrical pulse patterns, our synapse could produce transmembrane ionic current-induced spiking, which is highly analogous to biological action potentials with similar phases and excitability. Moreover, the spiking properties could be modulated by ions and neurochemicals. We expect that this work could contribute to biomimetic spiking computing in solution.


Assuntos
Potenciais de Ação , Poliestirenos , Sinapses , Potenciais de Ação/fisiologia , Sinapses/fisiologia , Poliestirenos/química , Nanotecnologia/métodos , Nanotecnologia/instrumentação
6.
Exp Aging Res ; : 1-19, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023066

RESUMO

OBJECTIVE: To observe the effects of Tai Chi training on depression symptoms and serum kynurenine metabolites in perimenopausal women and explore the mechanism of Tai Chi training in anti-depression. METHODS: A total of 72 perimenopausal women with depression were randomly selected from Lishi District and divided into a Tai Chi training group (36 cases) and a control group (36 cases). At the same time, 36 perimenopausal healthy women were randomly selected as the normal group. The Tai Chi training group was intervened with 24 simplified Tai Chi exercises, and the depression self-rating scale was used to evaluate the depression status. The levels of tryptophan (Trp) and kynurenine (KYN) metabolites in serum were determined by high-performance liquid chromatography-ultraviolet detection. RESULTS: Before the experiment, compared with the normal healthy group, the depression self-rating scale scores, serum KYN and quinolinic acid (QUIN) levels, and KYN/Trp ratio of the control group and Tai Chi group were significantly increased (p < .01), and the serum kynurenic acid (KYNA) level was significantly decreased (p < .01). After the experiment, compared with the normal healthy group, the depression self-rating scale scores of the Tai Chi group were significantly decreased (p < .01), the serum KYNA content was increased (p < .01), the serum KYN and QUIN contents were significantly decreased (p < .01), and the KYN/Trp ratio was significantly decreased (p < .01). CONCLUSION: Tai Chi training can significantly improve depression symptoms in perimenopausal women. The mechanism of Tai Chi training in improving depression symptoms in perimenopausal women may be achieved by regulating abnormal kynurenine metabolism.


Depression is the most common psychological disorder in perimenopausal women. A series of active substances produced by tryptophan metabolism through kynurenine pathway are closely related to the occurrence and development of depression.One of China's unique traditional sports, Tai Chi is a fitness exercise that combines sport and medical treatment, suitable for groups of all ages and levels.Tai Chi training significantly improved depressive symptoms in perimenopausal women, and the mechanism may be through altering abnormal decreases in KYN metabolism.

7.
Adv Mater ; : e2401920, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39011802

RESUMO

Responsive materials and actuators are the basis for the development of various leading-edge technologies but have so far mostly been designed based on polymers, incurring key limitations related to sensitivity and environmental tolerance. This work reports a new responsive material, laser-printed carbon film (LPCF), produced via direct laser transformation of a liquid organic precursor and consists of graphitic and amorphous carbons. The high activity of amorphous carbon combined with the dual-gradient structure enables the LPCF to have a actuation speed of 9400° s-1 in response to the stimulus of organic vapor. LPCF exhibits a conductivity of 950 S m-1 and excellent resistance to various extreme environmental conditions, which are unachievable for polymer-based materials. Additionally, an LPCF-based all-carbon soft robot that can mimic the complex continuous backward somersaulting motions without manual intervention is constructed. The locomotion velocity of the robot reaches a value of 1.19 BL s-1, which is almost one to two orders of magnitude faster than that of reported soft robots. This work not only offers a new paradigm for highly responsive materials but also provides a great design and engineering example for the next generation of biomimetic robots with life-like performance.

8.
J Neuroeng Rehabil ; 21(1): 98, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851703

RESUMO

PURPOSE: This pilot study aimed to investigate the effects of REX exoskeleton rehabilitation robot training on the balance and lower limb function in patients with sub-acute stroke. METHODS: This was a pilot, single-blind, randomized controlled trial. Twenty-four patients with sub-acute stroke (with the course of disease ranging from 3 weeks to 3 months) were randomized into two groups, including a robot group and a control group. Patients in control group received upright bed rehabilitation (n = 12) and those in robot group received exoskeleton rehabilitation robot training (n = 12). The frequency of training in both groups was once a day (60 min each) for 5 days a week for a total of 4 weeks. Besides, the two groups were evaluated before, 2 weeks after and 4 weeks after the intervention, respectively. The primary assessment index was the Berg Balance Scale (BBS), whereas the secondary assessment indexes included the Fugl-Meyer Lower Extremity Motor Function Scale (FMA-LE), the Posture Assessment Scale for Stroke Patients (PASS), the Activities of Daily Living Scale (Modified Barthel Index, MBI), the Tecnobody Balance Tester, and lower extremity muscle surface electromyography (sEMG). RESULTS: The robot group showed significant improvements (P < 0.05) in the primary efficacy index BBS, as well as the secondary efficacy indexes PASS, FMA-LE, MBI, Tecnobody Balance Tester, and sEMG of the lower limb muscles. Besides, there were a significant differences in BBS, PASS, static eye-opening area or dynamic stability limit evaluation indexes between the robotic and control groups (P < 0.05). CONCLUSIONS: This is the first study to investigate the effectiveness of the REX exoskeleton rehabilitation robot in the rehabilitation of patients with stroke. According to our results, the REX exoskeleton rehabilitation robot demonstrated superior potential efficacy in promoting the early recovery of balance and motor functions in patients with sub-acute stroke. Future large-scale randomized controlled studies and follow-up assessments are needed to validate the current findings. CLINICAL TRIALS REGISTRATION: URL: https://www.chictr.org.cn/index.html.Unique identifier: ChiCTR2300068398.


Assuntos
Exoesqueleto Energizado , Extremidade Inferior , Equilíbrio Postural , Robótica , Reabilitação do Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/instrumentação , Reabilitação do Acidente Vascular Cerebral/métodos , Masculino , Projetos Piloto , Feminino , Pessoa de Meia-Idade , Extremidade Inferior/fisiopatologia , Equilíbrio Postural/fisiologia , Método Simples-Cego , Robótica/instrumentação , Idoso , Adulto , Acidente Vascular Cerebral/fisiopatologia , Eletromiografia , Resultado do Tratamento , Recuperação de Função Fisiológica
9.
Neurochem Res ; 49(8): 2148-2164, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38822986

RESUMO

Carbon monoxide poisoning (COP) represents a significant global health burden, characterized by its morbidity and high mortality rates. The pathogenesis of COP-induced brain injury is complex, and effective treatment modalities are currently lacking. In this study, we employed network pharmacology to identify therapeutic targets and associated signaling pathways of Zhuli Decoction (ZLD) for COP. Subsequently, we conducted both in vitro and in vivo experiments to validate the therapeutic efficacy of ZLD in combination with N-butylphthalide (NBP) for acute COP-induced injury. Our network pharmacology analysis revealed that the primary components of ZLD exerted therapeutic effects through the modulation of multiple targets and pathways. The in vitro and in vivo experiments demonstrated that the combination of NBP and ZLD effectively inhibited apoptosis and up-regulated the activities of P-PI3K (Tyr458), P-AKT (Ser473), P-GSK-3ß (Ser9), and Bcl-2, thus leading to the protection of neuronal cells and improvement in cognitive function in rats following COP, which was better than the effects observed with NBP or ZLD alone. The rescue experiment further showed that LY294002, a PI3K inhibitor, significantly attenuated the therapeutic efficacy of NBP + ZLD. The neuroprotection effects of NBP and ZLD against COP-induced brain injury are closely linked to the activation of the PI3K/AKT/GSK-3ß signaling pathway.


Assuntos
Apoptose , Benzofuranos , Glicogênio Sintase Quinase 3 beta , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Ratos Sprague-Dawley , Transdução de Sinais , Animais , Benzofuranos/farmacologia , Benzofuranos/uso terapêutico , Apoptose/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Masculino , Ratos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Quimioterapia Combinada
10.
Neuromolecular Med ; 26(1): 27, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935278

RESUMO

Glioma is the most common primary intracranial tumor with high mortality and poor prognosis. The purpose of this study was to investigate how single-nucleotide polymorphisms (SNPs) of the NID2 gene affect glioma risk and prognosis. Four candidate SNPs of NID2 in 529 glioma patients and 478 healthy controls were successfully genotyped by Agena MassARRAY mass spectrometer. Logistic regression was utilized to assess the associations between NID2 SNPs and glioma risk under different genetic models. Furthermore, the relationship between risk-related SNPs in NID2 and the prognosis of glioma patients was explored through Kaplan-Meier (KM) survival curve and Cox proportional hazard regression analysis. The results showed that rs11846847 (OR 1.24, p = 0.017) and rs1874569 (OR 1.22, p = 0.026) were significantly associated with an increased risk of glioma, and rs11846847 also had a risk-increasing effect on glioma in participants ≤ 40 years old. The interaction model of rs11846847 and rs1874569 could be more suitable for forecasting glioma risk. We also discovered a significant association between rs1874569 and poor prognosis in glioma patients (HR 1.32, p = 0.039) and especially CC genotype was relevant to shorter overall survival (OS) and progression-free survival (PFS) in patients with high-grade glioma. Additionally, the study demonstrated that gross total resection or chemotherapy improve glioma prognosis in the Chinese Han population. This study is the first to provide evidence for the association of NID2 SNPs with glioma risk and prognosis, suggesting that NID2 variants might be potential factors for glioma.


Assuntos
Povo Asiático , Neoplasias Encefálicas , Proteínas de Ligação ao Cálcio , Predisposição Genética para Doença , Glioma , Polimorfismo de Nucleotídeo Único , Humanos , Glioma/genética , Glioma/mortalidade , Feminino , Masculino , Neoplasias Encefálicas/genética , Prognóstico , Adulto , Pessoa de Meia-Idade , Povo Asiático/genética , Proteínas de Ligação ao Cálcio/genética , China/epidemiologia , Estudos de Casos e Controles , Estimativa de Kaplan-Meier , Genótipo , Modelos de Riscos Proporcionais , Fatores de Risco , População do Leste Asiático , Moléculas de Adesão Celular
11.
Medicine (Baltimore) ; 103(18): e38038, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701277

RESUMO

The present study aimed to establish an effective prognostic nomogram model based on the Naples prognostic score (NPS) for resectable thoracic esophageal squamous cell carcinoma (ESCC). A total of 277 patients with ESCC, who underwent standard curative esophagectomy and designated as study cohort, were retrospectively analyzed. The patients were divided into different groups, including NPS 0, NPS 1, NPS 2, and NPS 3 or 4 groups, for further analysis, and the results were validated in an external cohort of 122 ESCC patients, who underwent surgery at another cancer center. In our multivariate analysis of the study cohort showed that the tumor-node-metastasis (TNM) stage, systemic inflammation score, and NPS were the independent prognostic factors for the overall survival (OS) and progression-free survival (PFS) durations. In addition, the differential grade was also an independent prognostic factor for the OS in the patients with ESCC after surgery (all P < .05). The area under the curve of receiver operator characteristics for the PFS and OS prediction with systemic inflammation score and NPS were 0.735 (95% confidence interval [CI] 0.676-0.795, P < .001) and 0.835 (95% CI 0.786-0.884, P < .001), and 0.734 (95% CI 0.675-0.793, P < .001) and 0.851 (95% CI 0.805-0.896, P < .001), respectively. The above independent predictors for OS or PFS were all selected in the nomogram model. The concordance indices (C-indices) of the nomogram models for predicting OS and PFS were 0.718 (95% CI 0.681-0.755) and 0.669 (95% CI 0.633-0.705), respectively, which were higher than that of the 7th edition of American Joint Committee on Cancer TNM staging system [C-index 0.598 (95% CI 0.558-0.638) for OS and 0.586 (95% CI 0.546-0.626) for PFS]. The calibration curves for predicting the 5-year OS or PFS showed a good agreement between the prediction by nomogram and actual observation. In the external validation cohort, the nomogram discrimination for OS was better than that of the 7th edition of TNM staging systems [C-index: 0.697 (95% CI 0.639-0.755) vs 0.644 (95% CI 0.589-0.699)]. The calibration curves showed good consistency in predicting the 5-year survival between the actual observation and nomogram predictions. The decision curve also showed a higher potential of the clinical application of predicting the 5-years OS of the proposed nomogram model as compared to that of the 7th edition of TNM staging systems. The preoperative NPS-based nomogram model had a certain potential role for predicting the prognosis of ESCC patients.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Esofagectomia , Nomogramas , Humanos , Masculino , Feminino , Estudos Retrospectivos , Carcinoma de Células Escamosas do Esôfago/cirurgia , Carcinoma de Células Escamosas do Esôfago/mortalidade , Carcinoma de Células Escamosas do Esôfago/patologia , Pessoa de Meia-Idade , Neoplasias Esofágicas/cirurgia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Prognóstico , Esofagectomia/métodos , Idoso , Estadiamento de Neoplasias , Adulto
12.
Front Cardiovasc Med ; 11: 1364332, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707890

RESUMO

Background: Postoperative acute kidney injury (PO-AKI) is a prevalent complication among patients with acute type A aortic dissection (aTAAD) for which unrecognized trajectories of renal function recovery, and their heterogeneity, may underpin poor success in identifying effective therapies. Methods: This was a retrospective, single-center cohort study in a regional Great Vessel Center including patients undergoing aortic dissection surgery. Estimated glomerular filtration rate (eGFR) recovery trajectories of PO-AKI were defined through the unsupervised latent class mixture modeling (LCMM), with an assessment of patient and procedural characteristics, complications, and early-term survival. Internal validation was performed by resampling. Results: A total of 1,295 aTAAD patients underwent surgery and 645 (49.8%) developed PO-AKI. Among the PO-AKI cohort, the LCMM identified two distinct eGFR trajectories: early recovery (ER-AKI, 51.8% of patients) and late or no recovery (LNR-AKI, 48.2% of patients). Binary logistic regression identified five critical determinants regarding poor renal recovery, including chronic kidney disease (CKD) history, renal hypoperfusion, circulation arrest time, intraoperative urine, and myoglobin. LNR-AKI was associated with increased mortality, continuous renal replacement therapies, mechanical ventilation, ICU stay, and hospital stay. The assessment of the predictive model was good, with an area under the curve (AUC) of 0.73 (95% CI: 0.69-0.76), sensitivity of 61.74%, and specificity of 75.15%. The internal validation derived a consistent average AUC of 0.73. The nomogram was constructed for clinicians' convenience. Conclusion: Our study explored the PO-AKI recovery patterns among surgical aTAAD patients and identified critical determinants that help to predict individuals at risk of poor recovery of renal function.

13.
Cereb Cortex ; 34(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38771245

RESUMO

Arterial spin-labeled perfusion and blood oxygenation level-dependent functional MRI are indispensable tools for noninvasive human brain imaging in clinical and cognitive neuroscience, yet concerns persist regarding the reliability and reproducibility of functional MRI findings. The circadian rhythm is known to play a significant role in physiological and psychological responses, leading to variability in brain function at different times of the day. Despite this, test-retest reliability of brain function across different times of the day remains poorly understood. This study examined the test-retest reliability of six repeated cerebral blood flow measurements using arterial spin-labeled perfusion imaging both at resting-state and during the psychomotor vigilance test, as well as task-induced cerebral blood flow changes in a cohort of 38 healthy participants over a full day. The results demonstrated excellent test-retest reliability for absolute cerebral blood flow measurements at rest and during the psychomotor vigilance test throughout the day. However, task-induced cerebral blood flow changes exhibited poor reliability across various brain regions and networks. Furthermore, reliability declined over longer time intervals within the day, particularly during nighttime scans compared to daytime scans. These findings highlight the superior reliability of absolute cerebral blood flow compared to task-induced cerebral blood flow changes and emphasize the importance of controlling time-of-day effects to enhance the reliability and reproducibility of future brain imaging studies.


Assuntos
Encéfalo , Circulação Cerebrovascular , Imageamento por Ressonância Magnética , Descanso , Humanos , Masculino , Feminino , Adulto , Circulação Cerebrovascular/fisiologia , Reprodutibilidade dos Testes , Descanso/fisiologia , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Encéfalo/irrigação sanguínea , Adulto Jovem , Imageamento por Ressonância Magnética/métodos , Imagem de Perfusão/métodos , Desempenho Psicomotor/fisiologia , Ritmo Circadiano/fisiologia , Nível de Alerta/fisiologia
14.
ACS Appl Mater Interfaces ; 16(21): 27952-27960, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808703

RESUMO

Capable of directly capturing various physiological signals from human skin, skin-interfaced bioelectronics has emerged as a promising option for human health monitoring. However, the accuracy and reliability of the measured signals can be greatly affected by body movements or skin deformations (e.g., stretching, wrinkling, and compression). This study presents an ultraconformal, motion artifact-free, and multifunctional skin bioelectronic sensing platform fabricated by a simple and user-friendly laser patterning approach for sensing high-quality human physiological data. The highly conductive membrane based on the room-temperature coalesced Ag/Cu@Cu core-shell nanoparticles in a mixed solution of polymers can partially dissolve and locally deform in the presence of water to form conformal contact with the skin. The resulting sensors to capture improved electrophysiological signals upon various skin deformations and other biophysical signals provide an effective means to monitor health conditions and create human-machine interfaces. The highly conductive and stretchable membrane can also be used as interconnects to connect commercial off-the-shelf chips to allow extended functionalities, and the proof-of-concept demonstration is highlighted in an integrated pulse oximeter. The easy-to-remove feature of the resulting device with water further allows the device to be applied on delicate skin, such as the infant and elderly.


Assuntos
Dispositivos Eletrônicos Vestíveis , Humanos , Pele/química , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Prata/química , Cobre/química , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Artefatos , Nanopartículas Metálicas/química , Movimento (Física) , Condutividade Elétrica
15.
Acta Radiol ; : 2841851241246364, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715339

RESUMO

BACKGROUND: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with an extended Tofts linear (ETL) model for tissue and tumor evaluation has been established, but its effectiveness in evaluating the pancreas remains uncertain. PURPOSE: To understand the pharmacokinetics of normal pancreas and serve as a reference for future studies of pancreatic diseases. MATERIAL AND METHODS: Pancreatic pharmacokinetic parameters of 54 volunteers were calculated using DCE-MRI with the ETL model. First, intra- and inter-observer reliability was assessed through the use of the intra-class correlation coefficient (ICC) and coefficient of variation (CoV). Second, a subgroup analysis of the pancreatic DCE-MRI pharmacokinetic parameters was carried out by dividing the 54 individuals into three groups based on the pancreatic region, three groups based on age, and two groups based on sex. RESULTS: There was excellent agreement and low variability of intra- and inter-observer to pancreatic DCE-MRI pharmacokinetic parameters. The intra- and inter-observer ICCs of Ktrans, kep, ve, and vp were 0.971, 0.952, 0.959, 0.944 and 0.947, 0.911, 0.978, 0.917, respectively. The intra- and inter-observer CoVs of Ktrans, kep, ve, vp were 9.98%, 5.99%, 6.47%, 4.76% and 10.15%, 5.22%, 6.28%, 5.40%, respectively. Only the pancreatic ve of the older group was higher than that of the young and middle-aged groups (P = 0.042, 0.001), and the vp of the pancreatic head was higher than that of the pancreatic body and tail (P = 0.014, 0.043). CONCLUSION: The application of DCE-MRI with an ETL model provides a reliable, robust, and reproducible means of non-invasively quantifying pancreatic pharmacokinetic parameters.

16.
Opt Lett ; 49(9): 2401-2404, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691729

RESUMO

Transition-metal dichalcogenides (TMDCs), as emerging optoelectronic materials, necessitate the establishment of an experimentally viable system to study their interaction with light. In this study, we propose and analyze a WS2/PMMA/Ag planar Fabry-Perot (F-P) cavity, enabling the direct experimental measurement of WS2 absorbance. By optimizing the structure, the absorbance of A exciton of WS2 up to 0.546 can be experimentally achieved, which matches well with the theoretical calculations. Through temperature and thermal expansion strain induced by temperature, the absorbance of the A exciton can be tuned in situ. Furthermore, temperature-dependent photocurrent measurements confirmed the consistent absorbance of the A exciton under varying temperatures. This WS2/PMMA/Ag planar structure provides a straightforward and practical platform for investigating light interaction in TMDCs, laying a solid foundation for future developments of TMDC-based optoelectronic devices.

17.
Lab Chip ; 24(12): 3080-3092, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38747247

RESUMO

Digital PCR is a powerful method for absolute nucleic acid quantification and is widely used in the absolute quantification of viral copy numbers, tumor marker detection, and prenatal diagnosis. However, for most of the existing droplet-based dPCR systems, the droplet generation, PCR reaction, and droplet detection are performed separately using different instruments. Making digital PCR both easy to use and practical by integrating the qPCR workflow into a superior all-in-one walkaway solution is one of the core ideas. A new innovative and integrated digital droplet PCR platform was developed that utilizes cutting-edge microfluidics to integrate dPCR workflows onto a single consumable chip. This makes previously complex workflows fast and simple; the whole process of droplet generation, PCR amplification, and droplet detection is completed on one chip, which meets the clinical requirement of "sample in, result out". It provides high multiplexing capabilities and strong sensitivity while all measurements were within the 95% confidence interval. This study is the first validation of the DropXpert S6 system and focuses primarily on verifying its reliability, repeatability, and consistency. In addition, the accuracy, detection limit, linearity, and precision of the system were evaluated after sample collection. Among them, the accuracy assessment by calculating the absolute bias of each target gene yielded a range from -0.1 to 0.08, all within ±0.5 logarithmic orders of magnitude; the LOB for the assay was set at 0, and the LoD value calculated using probit curves is MR4.7 (0.002%); the linearity evaluation showed that the R2 value of the BCR-ABL was 0.9996, and the R2 value of the ABL metrics calculated using the ERM standard was 0.9999; and the precision evaluation showed that all samples had a CV of less than 4% for intra-day, inter-day, and inter-instrument variation. The CV of inter-batch variation was less than 7%. The total CV was less than 5%. The results of the study demonstrate that dd-PCR can be applied to molecular detection and the clinical evaluation of CML patients and provide more precise personal treatment guidance, and its reproducibility predicts the future development of a wide range of clinical applications.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Dispositivos Lab-On-A-Chip , Proteínas de Fusão bcr-abl/genética , Reação em Cadeia da Polimerase , Técnicas Analíticas Microfluídicas/instrumentação
18.
J Chromatogr A ; 1726: 464963, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38723493

RESUMO

The monitoring of organic compounds in aquatic matrices poses challenges due to its complexity and time-intensive nature. To address these challenges, we introduce a novel approach utilizing a dual-channel mono (1D) and comprehensive two-dimensional (2D) gas chromatography coupled with time-of-flight mass spectrometry (GC × GC-TOFMS) system, integrated with a robotic pretreatment platform, for online monitoring of both volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) in water matrices. Employing the robotic platform, we establish a suite of online liquid-liquid extraction (LLE) pretreatment processes for water samples, marking the first instance of such procedures. Leveraging the automatic headspace (HS) module, dual robotic preparations of HS and LLE are sequentially executed to extract VOCs and SVOCs from water matrices. The GC × GC-TOFMS system is distinguished by its dual-channel analytical column configuration, facilitating sequential analysis of VOCs in GC-TOFMS mode and SVOCs in GC × GC-TOFMS mode. Quantitative detection of 55 target VOCs and 104 SVOCs is achieved in a water sample using the instrument system. Our method demonstrates excellent correlation coefficients ranging from 0.990 to 1.000, method detection limits ranging from 0.08 to 4.78 µg L-1, relative standard deviations below 19.3 %, and recovery rates ranging from 50.0 % to 124.0 %. To validate the online monitoring capabilities of our system, we assess target SVOCs at three different concentration levels over a 3-day period. Most compounds exhibit recovery rates ranging from 70.0 % to 130.0 %. Furthermore, we apply our method to analyze a real water sample, successfully identifying over 100 target and nontarget VOCs/SVOCs, including alcohols, aldehydes, ketones, acids, esters, and phenols. These results highlight the efficacy of the proposed analysis system, capable of conducting two distinct analyses in automatic sequence, thereby enhancing the efficiency and accuracy of organic compound analysis in water matrices.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Extração Líquido-Líquido , Robótica , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Extração Líquido-Líquido/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Limite de Detecção
19.
Anal Chem ; 96(16): 6444-6449, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38597812

RESUMO

As two mainstream ionic detection techniques, ionic current rectification (ICR) suffers from large fluctuations in trace level detection, while resistive-pulse sensing (RPS) encounters easy clogs in high-concentration detection. By rationally matching the nanopore size with the DNA tetrahedron (TDN), this work bridges the two techniques to achieve reliable detection with wide linearity. As a representative analyte, miRNA-10b could specifically combine with and release TDN from the interior wall, which thus induced the simultaneous generation of distinct ICR and RPS signals. The ICR signals could be attributed to the balance between the effective orifice and surface charge density of the inner wall, while the RPS signals were induced by the complex of miRNA-10b and TDN passing through the nanopore. Such an operation contributed to a wide detection range of 1 fM-1 nM with a good linearity. The feasibility of this method is also validated in single-cell and real plasma detection.

20.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(2): 267-272, 2024 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-38595243

RESUMO

OBJECTIVE: To analyze the clinical characteristics of hemodialysis patients with corona virus disease 2019 (COVID-19) in a single-center from Beijing. METHODS: Patients with COVID-19 who received regular hemodialysis at Peking University Third Hospital from November 30, 2022 to January 4, 2023 were selected as the study objects. Clinical symptoms, severity and duration of symptoms during the period of virus positive were investigated in the form of questionnaires, and the basic information of the patients, as well as the results of blood tests (routine blood and blood biochemistry, etc.) before and after infection, dialysis treatment and the outcome of the disease were collected by consulting medical records. RESULTS: A total of 203 subjects were included in this study, including 148 mild cases (72.91%), 23 medium cases (11.33%), 32 severe and critical cases (15.76%), and 16 (7.88%) deaths occured during the follow-up. Clinical symptoms mainly included respiratory symptoms (among which 81.77% had cough, 68.97% had expectoration), fever (81.28%) and fatigue (65.52%), and fatigue and weakness had the longest duration [9 (5, 15) days] among all symptoms. Twenty-six patients (12.8%) reduced the dialysis sessions [1 (1, 2) times], 25 patients (12.32%) had the behavior of early finishing dialysis (27 times), reducing the dialysis time by 30.0 (20.0, 30.5) minutes. Univa-riate analysis showed that the hemoglobin, creatinine, urea nitrogen and ultrafiltration decreased signi-ficantly after infection (P < 0.05). There were significant differences in age, albumin, hemoglobin, creatinine levels and vascular access types among the patients with different clinical subtypes, and the changes of dialysis sessions, fever, expectoration and fatigue degree were also different among the patients with different clinical subtypes (P < 0.05). Multivariate Logistic regression analysis showed that age (OR=1.051, 95%CI: 1.017-1.086, P=0.003) and albumin levels (OR=0.905, 95%CI: 0.803-1.019, P=0.098) corrected by fever, expectoration and fatigue levels were still associated with the occurrence of pneumonia. CONCLUSION: The morbidity of pneumonia and the proportion of deaths in hemodialysis patients with COVID-19 were higher, and some clinical symptoms lasted for a longer time than the general population. During the infection period, the incidence of dialysis-related complications increased, hemoglobin and nutritional status decreased. Elderly patients and patients with low albumin level had a higher risk of developing pneumonia after infection.


Assuntos
COVID-19 , Humanos , Idoso , COVID-19/epidemiologia , COVID-19/terapia , Creatinina , Diálise Renal , Albuminas , Hemoglobinas
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