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1.
Neural Regen Res ; 20(1): 224-233, 2025 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38767487

RESUMEN

JOURNAL/nrgr/04.03/01300535-202501000-00030/figure1/v/2024-05-14T021156Z/r/image-tiff Axonal remodeling is a critical aspect of ischemic brain repair processes and contributes to spontaneous functional recovery. Our previous in vitro study demonstrated that exosomes/small extracellular vesicles (sEVs) isolated from cerebral endothelial cells (CEC-sEVs) of ischemic brain promote axonal growth of embryonic cortical neurons and that microRNA 27a (miR-27a) is an elevated miRNA in ischemic CEC-sEVs. In the present study, we investigated whether normal CEC-sEVs engineered to enrich their levels of miR-27a (27a-sEVs) further enhance axonal growth and improve neurological outcomes after ischemic stroke when compared with treatment with non-engineered CEC-sEVs. 27a-sEVs were isolated from the conditioned medium of healthy mouse CECs transfected with a lentiviral miR-27a expression vector. Small EVs isolated from CECs transfected with a scramble vector (Scra-sEVs) were used as a control. Adult male mice were subjected to permanent middle cerebral artery occlusion and then were randomly treated with 27a-sEVs or Scra-sEVs. An array of behavior assays was used to measure neurological function. Compared with treatment of ischemic stroke with Scra-sEVs, treatment with 27a-sEVs significantly augmented axons and spines in the peri-infarct zone and in the corticospinal tract of the spinal grey matter of the denervated side, and significantly improved neurological outcomes. In vitro studies demonstrated that CEC-sEVs carrying reduced miR-27a abolished 27a-sEV-augmented axonal growth. Ultrastructural analysis revealed that 27a-sEVs systemically administered preferentially localized to the pre-synaptic active zone, while quantitative reverse transcription-polymerase chain reaction and Western Blot analysis showed elevated miR-27a, and reduced axonal inhibitory proteins Semaphorin 6A and Ras Homolog Family Member A in the peri-infarct zone. Blockage of the Clathrin-dependent endocytosis pathway substantially reduced neuronal internalization of 27a-sEVs. Our data provide evidence that 27a-sEVs have a therapeutic effect on stroke recovery by promoting axonal remodeling and improving neurological outcomes. Our findings also suggest that suppression of axonal inhibitory proteins such as Semaphorin 6A may contribute to the beneficial effect of 27a-sEVs on axonal remodeling.

2.
Risk Manag Healthc Policy ; 17: 2271-2280, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39355058

RESUMEN

Objective: This study investigates the prevalence and determinants of social isolation in peritoneal dialysis (PD) patients, focusing on the influence of environmental systems and individual behaviors on their social well-being. Methods: We conducted a cross-sectional study from December 2023 to February 2024 at Shenzhen Traditional Chinese Medicine Hospital. A total of 259 PD patients were enrolled using a consecutive sampling method. Data were collected via validated tools including the Pittsburgh Sleep Quality Index (PSQI), Lubben Social Network Scale-6 (LSNS-6), Family APGAR Questionnaire, and Social Anxiety Subscale of Self-Consciousness Scale (SASS-CS). Statistical analyses utilized Spearman correlation and multiple linear regression to identify factors associated with social isolation. Results: The average score for social isolation was 11 (range 7-15). Significant predictors of social isolation included education level, physical inactivity, and normal hemoglobin concentrations. Social isolation was negatively correlated with family functionality and positively correlated with social anxiety. Regression analysis confirmed education, family functionality, and social anxiety as significant independent predictors of social isolation. Conclusion: Social isolation is common among PD patients, driven by factors such as education level, physical inactivity, and unexpectedly, normal hemoglobin levels linked to greater family isolation. Targeted interventions like education, physical activity promotion, and innovative therapies such as animal-assisted activities and social gardening can help reduce isolation and improve patient well-being.


1. Why is this study needed? Peritoneal dialysis is a common treatment for severe kidney disease. This study is crucial because it examines how being isolated affects patients undergoing this treatment, as social isolation can worsen their health outcomes. 2. What is the key problem/issue/question this manuscript addresses? The main issue addressed is understanding the factors that contribute to social isolation in peritoneal dialysis patients and how this isolation impacts their health and quality of life. 3. What is the main point of your study? The study explores how various factors such as education levels, physical activity, and family support influence social isolation among these patients. It also looks at the broader environmental and social settings that affect their interactions and mental health. 4. What are your main results and what do they mean? Our findings show that patients with higher education, better family support, and more physical activity are less socially isolated. Addressing these factors can greatly enhance the well-being and social interactions of peritoneal dialysis patients, suggesting the need for targeted support and community integration initiatives.

3.
Biosens Bioelectron ; 267: 116799, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39312835

RESUMEN

Alcohol sensing plays a critical role in medical detection and personal health management. AIE materials with high sensitivity, selectivity and fast response have been widely used in biosensing, but their application in the field of alcohol sensing still needs further research and development. Furthermore, developing flexible phase change materials (PCMs) is significant for the research of human-body thermal management. In this study, a kind of flexible polyacrylonitrile (PAN)/polyvinylpyrrolidone (PVP)/polyethylene glycol (PEG)/Py-CH (pyrene-based AIE molecule)/SiO2@h-BN composite fiber textile (PAB) with alcohol sensing performance, writable fluorescence property, and human body thermal management function has been prepared via electrospinning technique. The PAN/PVP fiber matrix successfully integrated AIE fluorescent sensing material and PCM into a multi-functional composite with great shape stability. Owing to the introduction of novel pyrene-based Py-CH with AIE characteristic, this innovative textile exhibited wonderful fluorescent properties, including sensitive alcohol fluorescence sensing, writable fluorescence performance and variable temperature fluorescence. Furthermore, proposed PAB textile delivered a high energy storage density of 87∼90 J/g, excellent thermal reliability, great comprehensive mechanical flexibility and enhanced thermal conductivity for flexible human body thermal management. Hence, this flexible multifunctional AIE/PCM composite sensing textiles can be widely used in alcohol sensing, fluorescence anti-counterfeiting and flexible body thermal management.

4.
Heliyon ; 10(18): e36984, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39315208

RESUMEN

The world faces two significant challenges: promoting sustainable economic growth and reaching carbon neutrality. In BRICS countries, these challenges are shaped by renewable energy, green taxes, and trade openness. These countries were selected for their strategic location and the abundance of relevant data collected over the period of 1990-2021, providing a distinctive window into the energy and economic dynamics of the area. The link between renewable energy consumption, green taxes, trade openness, and natural resources and their effects on carbon emissions in BRICS countries is examined in this study using the Fully Modified Ordinary Least Square Method (FMOLS) estimator and the Drisc Kraay estimator for the robustness test. The findings indicate that using renewable energy and green taxes primarily contribute to reducing emissions, particularly at higher emissions levels. The study reveals that various factors, namely financial globalization, trade openness, efficient resource management, and population growth, substantially impact carbon neutrality. Population growth positively impacts carbon neutrality, while using renewable energy sources mitigates it. Furthermore, the empirical findings show a statistically significant positive association between financial globalization, efficient resource management, and carbon neutrality in BRICS nations. Therefore, it is necessary to implement an integrated ecological governance strategy to control and direct financial resources towards sustainable development and green energy.

5.
J Immunol ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39258879

RESUMEN

B cell activation is accompanied by dynamic metabolic reprogramming, supported by a multitude of nutrients that include glucose, amino acids, and fatty acids. Although several studies have indicated that fatty acid mitochondrial oxidation is critical for immune cell functions, contradictory findings have been reported. Carnitine palmitoyltransferase II (CPT2) is a critical enzyme for long-chain fatty acid oxidation in mitochondria. In this study, we test the requirement of CPT2 for humoral immunity using a mouse model with a lymphocyte-specific deletion of CPT2. Stable [13C] isotope tracing reveals highly reduced fatty acid-derived citrate production in CPT2-deficient B cells. Yet, CPT2 deficiency has no significant impact on B cell development, B cell activation, germinal center formation, and Ab production upon either thymus-dependent or -independent Ag challenges. Together, our findings indicate that CPT2-mediated fatty acid oxidation is dispensable for humoral immunity, highlighting the metabolic flexibility of lymphocytes.

6.
Materials (Basel) ; 17(18)2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39336219

RESUMEN

The widespread adoption of arc additive manufacturing techniques across various industries has advanced the field of SS316L stainless steel manufacturing. It is crucial to acknowledge that different welding modes exert distinct influences on the forming and mechanical performance. This study analyzed the thermal input associated with four specific welding modes in LORCH MIG welding, clarifying the transition dynamics of molten droplets through waveform analysis and examining the resultant effects on microstructure and performance characteristics. The Pulse, Speed-Pulse-XT, and Twin-Pulse modes were found to induce spatter during the manufacturing process, consequently reducing molding efficiency in comparison to the SA-XT mode. Notably, the Twin-Pulse mode, characterized by double-pulse agitation, generated fish scale patterns along the lateral surfaces of the fabricated parts, promoting anisotropic grain growth. This microstructural refinement, compared to single-pulse samples with equivalent thermal input, resulted in enhanced mechanical properties. Nevertheless, the horizontal tensile strength of the three pulse modes was lower than the industrial standard for SA-XT mode and forging. In contrast, the SA-XT mode with an average hardness of 168.1 ± 6.9 HV and a tensile strength of 443.58 ± 5.7 MPa. Therefore, while three pulse modes offer certain microstructural advantages, the SA-XT mode demonstrates superior overall performance.

7.
Bioengineering (Basel) ; 11(9)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39329615

RESUMEN

BACKGROUND: Intraoral scans (IOS) provide precise 3D data of dental crowns and gingival structures. This paper explores an application of IOS in human identification. METHODS: We propose a dental biometrics framework for human identification using 3D dental point clouds based on machine learning-related algorithms, encompassing three stages: data preprocessing, feature extraction, and registration-based identification. In the data preprocessing stage, we use the curvature principle to extract distinguishable tooth crown contours from the original point clouds as the holistic feature identification samples. Based on these samples, we construct four types of local feature identification samples to evaluate identification performance with severe teeth loss. In the feature extraction stage, we conduct voxel downsampling, then extract the geometric and structural features of the point cloud. In the registration-based identification stage, we construct a coarse-to-fine registration scheme in order to realize the identification task. RESULTS: Experimental results on a dataset of 160 individuals demonstrate that our method achieves a Rank-1 recognition rate of 100% using complete tooth crown contours samples. Utilizing the remaining four types of local feature samples yields a Rank-1 recognition rate exceeding 96.05%. CONCLUSIONS: The proposed framework proves effective for human identification, maintaining high identification performance even in extreme cases of partial tooth loss.

8.
Clin Appl Thromb Hemost ; 30: 10760296241279800, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39262220

RESUMEN

Background: Thrombolytic therapy is essential for acute ischemic stroke (AIS) management but poses a risk of hemorrhagic transformation (HT), necessitating accurate prediction to optimize patient care. Methods: A comprehensive search was conducted across PubMed, Web of Science, Scopus, Embase, and Google Scholar, covering studies from inception until July 10, 2024. Studies were included if they used machine learning (ML) or deep learning algorithms to predict HT in AIS patients treated with thrombolysis. Exclusion criteria included studies involving endovascular treatments and those not evaluating model effectiveness. Data extraction and quality assessment were performed following PRISMA guidelines and using the Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) and Prediction Model Risk of Bias Assessment Tool (PROBAST) tools. Results: Out of 1943 identified records, 12 studies were included in the final analysis, encompassing 18 007 AIS patients who received thrombolytic therapy. The ML models demonstrated high predictive performance, with pooled area under the curve (AUC) values ranging from 0.79 to 0.95. Specifically, XGBoost models achieved AUCs of up to 0.953 and Artificial Neural Network (ANN) models reached up to 0.942. Sensitivity and specificity varied significantly, with the highest sensitivity at 0.90 and specificity at 0.99. Significant predictors of HT included age, glucose levels, NIH Stroke Scale (NIHSS) score, systolic and diastolic blood pressure, and radiomic features. Despite these promising results, methodological disparities and limited external validation highlighted the need for standardized reporting and further rigorous testing. Conclusion: ML techniques, especially XGBoost and ANN, show great promise in predicting HT following thrombolysis in AIS patients, enhancing risk stratification and clinical decision-making. Future research should focus on prospective study designs, standardized reporting, and integrating ML assessments into clinical workflows to improve AIS management and patient outcomes.


Asunto(s)
Accidente Cerebrovascular Hemorrágico , Accidente Cerebrovascular Isquémico , Aprendizaje Automático , Terapia Trombolítica , Humanos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Terapia Trombolítica/efectos adversos , Terapia Trombolítica/métodos , Accidente Cerebrovascular Hemorrágico/inducido químicamente , Accidente Cerebrovascular Hemorrágico/epidemiología , Medición de Riesgo/métodos
9.
Anal Chim Acta ; 1324: 343102, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39218581

RESUMEN

BACKGROUND: Hexavalent chromium (Cr (VI)) is highly carcinogenic to humans. Ascorbic acid (AA) deficiency can be hazardous to health. And the dual-effect fluorescence detection of them is an important research topic. Carbon dots (CDs) based on cellulose are excellent candidates for the fluorescence probes due to their low cost and environmental friendliness. But most of them exhibit shortwave emission, small Stokes shift and poor fluorescence performance, all of which limit their use. Therefore, there is an urgent need for cellulose CDs with longer emission wavelengths and larger Stokes shifts in dual-effect fluorescence detection of Cr (VI) and AA. RESULTS: Under optimal conditions (180 °C, 12 h), we prepared cellulose-based nitrogen-doped carbon dots (N-CDs) by a simple one-step hydrothermal process, which display longer emission wavelengths (ex: 370 nm, em: 510 nm), larger Stokes shifts (140 nm) and high fluorescence quantum yield (QY: 19.27 %). The continuous "turn-off" and "turn-off-on" fluorescence detection platforms were constructed based on the internal filtering effect (IFE) between Cr6+ and N-CDs, and Cr6+ reduced to Cr3+ by AA at pH = 6. The platform has been successfully simultaneous detect Cr (VI) and AA with a wide range of 0.01-40 µM and 0.1-100 µM. And the lowest limits of detection (LOD) are 0.0303 µM and 0.072 µM, respectively. In the presence of some other metals, non-metal ions and water-soluble acids in the fruits, this fluorescent platform can demonstrate a high level of interference immunity. SIGNIFICANCE AND NOVELTY: This represents the first yellow-green cellulose-based N-CDs with large Stokes shift for dual-effect detection of Cr (VI) and AA in real water samples and fresh fruits. The fluorescence detection platform has the advantage of low volume detection. Less than 2 mL of sample is required for testing and results are available in <5 min. This method is rare and supply a novel idea for the quantitative monitoring of Cr (VI) and AA.

10.
bioRxiv ; 2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39131369

RESUMEN

Objective: We aim to explore the role of mechanistic target of rapamycin complex (mTORC) 2 in systemic lupus erythematosus (SLE) development, the in vivo regulation of mTORC2 by type I interferon (IFN) signaling in autoimmunity, and to use mTORC2 targeting therapy to ameliorate lupus-like symptoms in an in vivo lupus mouse model and an in vitro coculture model using human PBMCs. Method: We first induced lupus-like disease in T cell specific Rictor, a key component of mTORC2, deficient mice by topical application of imiquimod (IMQ) and monitored disease development. Next, we investigated the changes of mTORC2 signaling and immunological phenotypes in type I IFNAR deficient Lpr mice. We then tested the beneficial effects of anti-Rictor antisense oligonucleotide (Rictor-ASO) in a mouse model of lupus: MRL/lpr mice. Finally, we examined the beneficial effects of RICTOR-ASO on SLE patients' PBMCs using an in vitro T-B cell coculture assay. Results: T cell specific Rictor deficient mice have reduced age-associated B cells, plasma cells and germinal center B cells, and less autoantibody production than WT mice following IMQ treatment. IFNAR1 deficient Lpr mice have reduced mTORC2 activity in CD4+ T cells accompanied by restored CD4+ T cell glucose metabolism, partially recovered T cell trafficking, and reduced systemic inflammation. In vivo Rictor-ASO treatment improves renal function and pathology in MRL/lpr mice, along with improved immunopathology. In human SLE (N = 5) PBMCs derived T-B coculture assay, RICTOR-ASO significantly reduce immunoglobulin and autoantibodies production (P < 0.05). Conclusion: Targeting mTORC2 could be a promising therapeutic for SLE.

11.
Zhonghua Nan Ke Xue ; 30(7): 653-657, 2024 Jul.
Artículo en Chino | MEDLINE | ID: mdl-39212402

RESUMEN

Of the complex causes of testicular pain, intervertebral disc degeneration is a nonnegligible one, which, however, often fails to get sufficient attention from doctors in clinical practice and consequently leads to misdiagnosis or missed diagnosis. This paper presents an overview of the pathogenesis and treatment of intervertebral disc-induced testicular pain in traditional Chinese and Western medicine, aiming to improve clinicians' understanding of this problem and provide some reference for the diagnosis and treatment of unexplained testicular pain. According to traditional Chinese medicine, the pathogenesis of intervertebral disc-induced testicular pain may be associated with exogenous cold and dampness, damp-heat invasion of Yin organs, qi and blood stagnation, and closely related to the liver, kidney and governor meridian. Western medicine believes that its pathogenesis may be related to nerve root stimulation, nerve root entrapment, Waller degeneration, referred pain, nerve hypersensitivity and other factors.


Asunto(s)
Degeneración del Disco Intervertebral , Medicina Tradicional China , Humanos , Masculino , Medicina Tradicional China/métodos , Degeneración del Disco Intervertebral/terapia , Dolor/etiología , Testículo , Disco Intervertebral , Enfermedades Testiculares/terapia
12.
World J Clin Cases ; 12(22): 5189-5195, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39109051

RESUMEN

BACKGROUND: This paper reports a rare presentation of multiple pulp stones (PSs) emerging in all teeth during mixed dentition. It offers valuable insights into the clinical diagnosis, treatment, and prognosis of multiple PSs, shedding light on their occurrence during the mixed dentition period. CASE SUMMARY: A 10-year-old girl presented with repeated pain in the mandibular right posterior teeth. Intraoral examination revealed carious lesions, abnormal tooth shapes, and anomalies in tooth number. Radiographic examinations showed multiple PSs with diverse shapes, sizes, and quantities in all teeth, alongside anomalies in tooth shape and number. Root canal therapy was initiated, but the patient initially lacked timely follow-up. Upon return for treatment completion, an extracted tooth revealed irregular calculus within the pulp cavity. CONCLUSION: This case underscores the importance of considering multiple PSs in mixed dentition, necessitating comprehensive evaluation and management strategies.

13.
Front Neurol ; 15: 1380287, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39165268

RESUMEN

Introduction: The increasing incidence of stroke globally has led to dysphagia becoming one of the most common complications in stroke patients, with significant impacts on patient outcomes. Accurate early screening for dysphagia is crucial to avoid complications and improve patient quality of life. Methods: Included studies involved stroke-diagnosed patients assessed for dysphagia using bedside screening tools. Data was sourced from Embase, PubMed, Web of Science, Scopus, and CINAHL, including publications up to 10 December 2023. The study employed both fixed-effect and random-effects models to analyze sensitivity, specificity, positive predictive value (PPV), and Negative Predictive Value (NPV), each with 95% confidence intervals. The random-effects model was particularly utilized due to observed heterogeneity in study data. Results: From 6,979 records, 21 studies met the inclusion criteria, involving 3,314 participants from 10 countries. The analysis included six assessment tools: GUSS, MASA, V-VST, BSST, WST, and DNTA, compared against gold-standard methods VFSS and FEES. GUSS, MASA, and V-VST showed the highest reliability, with sensitivity and specificity rates of 92% and 85% for GUSS, 89% and 83% for MASA, respectively. Heterogeneity among studies was minimal, and publication bias was low, enhancing the credibility of the findings. Conclusion: Our network meta-analysis underscores the effectiveness of GUSS, MASA, and V-VST in dysphagia screening for stroke patients, with high sensitivity and specificity making them suitable for diverse clinical settings. BSST and WST, with lower diagnostic accuracy, require more selective use. Future research should integrate patient-specific outcomes and standardize methodologies to enhance dysphagia screening tools, ultimately improving patient care and reducing complications. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/#recordDetails.

14.
Talanta ; 279: 126611, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39067202

RESUMEN

Peptidyl arginine deiminase 4 (PAD4) plays a critical role in many autoimmune diseases including rheumatoid arthritis. Herein, a trypsin assisted highly immunoassay method was established to determine PAD4 activity and screen potent inhibitors from herbal plants extracts and purified natural products. The method was applied to determine endogenous PAD4 activity in both cell and tissue lysates, as well as the inhibitory effects of 20 herbal plants and 50 purified natural products. The Cinnamomi ramulus extract showed strongest inhibitory potency with IC50 value lower than 5 µg/mL. Meanwhile, pyrroloquinoline quinone (PQQ), widely used as a dietary supplement, was discovered as a promising PAD4 inhibitor with an IC50 value lower than 4 µM. The inhibition kinetic analysis, drug affinity response target stability (DARTS) and molecular docking were performed to confirm the interaction between PQQ and PAD4. This method has great potential for researchers to monitor activities and discover potential inhibitors of PAD4.


Asunto(s)
Simulación del Acoplamiento Molecular , Extractos Vegetales , Arginina Deiminasa Proteína-Tipo 4 , Extractos Vegetales/química , Extractos Vegetales/farmacología , Humanos , Arginina Deiminasa Proteína-Tipo 4/antagonistas & inhibidores , Arginina Deiminasa Proteína-Tipo 4/metabolismo , Inmunoensayo/métodos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/análisis , Productos Biológicos/química , Productos Biológicos/farmacología , Tripsina/metabolismo , Tripsina/química , Evaluación Preclínica de Medicamentos , Animales
15.
Clin Nucl Med ; 49(10): 995-996, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39010313

RESUMEN

ABSTRACT: We reported imaging findings with a peculiar tau accumulation pattern in a 56 year-old woman with frontotemporal dementia caused by Q351R mutation in the microtubule-associated protein tau ( MAPT ) gene. She had a 10-year history of gradually worsening memory loss. 18 F-FDG PET demonstrated hypometabolism in medial temporal lobes, but 18 F-florbetapir PET manifested no abnormal amyloid beta deposition, which ruled out Alzheimer disease. 18 F-florzolotau PET showed tau proteins accumulated in medial temporal lobes, basal ganglia brainstem, and cerebellum. The pattern is different from other known MAPT gene mutation. Multitracer imaging can help differentiate between Alzheimer disease and frontotemporal dementia caused by MAPT mutation.


Asunto(s)
Demencia Frontotemporal , Mutación , Tomografía de Emisión de Positrones , Proteínas tau , Humanos , Proteínas tau/metabolismo , Proteínas tau/genética , Demencia Frontotemporal/diagnóstico por imagen , Demencia Frontotemporal/genética , Femenino , Persona de Mediana Edad , Compuestos de Anilina
16.
Eur J Immunol ; : e2451080, 2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39072720

RESUMEN

Although the functions of tyrosine phosphatases in T-cell biology have been extensively studied, our knowledge on the contribution of serine/threonine phosphatases in T cells remains poor. Protein phosphatase 2A (PP2A) is one of the most abundantly expressed serine/threonine phosphatases. It is important in thymocyte development and CD4+ T-cell differentiation. Utilizing a genetic model in which its catalytic subunit alpha isoform (PP2A Cα) is deleted in T cells, we investigated its contribution to CD8+ T-cell homeostasis and effector functions. Our results demonstrate that T-cell intrinsic PP2A Cα is critically required for CD8+ T-cell homeostasis in secondary lymphoid organs and intestinal mucosal site. Importantly, PP2A Cα-deficient CD8+ T cells exhibit reduced proliferation and survival. CD8+ T-cell antibacterial response is strictly dependent on PP2A Cα. Expression of Bcl2 transgene rescues CD8+ T-cell homeostasis in spleens, but not in intestinal mucosal site, nor does it restore defective antibacterial responses. Finally, proteomics and phosphoproteomics analyses reveal potential targets dependent on PP2A Cα, including mTORC1 and AKT. Thus, PP2A Cα is a key modulator of CD8+ T-cell homeostasis and effector functions.

17.
Talanta ; 278: 126492, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38955099

RESUMEN

Dysregulation of peptidyl arginine deiminase 4 (PAD4) is involved in a variety of diseases including rheumatoid arthritis (RA) and Alzheimer's disease (AD), and it has emerged as potential and promising therapeutic target. However, no PAD4 inhibitor is ready for clinical use. Immobilized enzyme screening technology has gained increasing attention due to its low cost, reusability, easy separation from the reaction mixture, and resistance to changes in environmental conditions. In this study, PAD4 was immobilized on the magnetic nanoparticles (MNP) to prolong its activity stability, and a simple and rapid screening strategy of traditional Chinese medicine inhibitors based on immobilized PAD4 was established. The PAD4 enzyme was immobilized on magnetic nanoparticles (MNP) via Schiff base reaction using glutaraldehyde (GA) as crosslinking agent. Compared with free PAD4, the resulting MNP@GA@PAD4 exhibited an enhanced tolerance to temperature and storage stability, and its reusability was greatly improved with 66 % of initial enzyme activity after being recycled 10 times. The inhibitory activity of the immobilized PAD4 was assessed using two known PAD4 inhibitors GSK484 and BB-Cl-amidine. The semi-maximum inhibitory concentrations (IC50) of GSK484 and BB-Cl-amidine for MNP@GA@PAD4 were 1.00 and 0.97 µM, respectively, for free PAD4 were 0.64 and 0.85 µM, respectively. Finally, the MNP@GA@PAD4 was employed to rapid screen of natural PAD4 inhibitors from forty traditional Chinese medicines (TCMs). Under the same conditions, the controlled experiment was conducted with free PAD4. The screening results of TCMs inhibitors on MNP@GA@PAD4 and free PAD4 were similar, the alcohol extracts of Cinnamomi Cortex and Caryophylli Flos had significant inhibitory effects on PAD4 enzyme activity. The IC50 values of Cinnamomi Cortex extract for MNP@GA@PAD4 and free PAD4 were determined as 27 and 48 µg/mL, respectively. The IC50 values of Caryophylli Flos extracts for MNP@GA@PAD4 and free PAD4 were determined as 48 and 32 µg/mL, respectively. For the first time, this study proposed a method to immobilize PAD4 on magnetic materials, and developed a rapid, reusable and feasible strategy to screening natural PAD4 inhibitors from TCMs.


Asunto(s)
Inhibidores Enzimáticos , Enzimas Inmovilizadas , Nanopartículas de Magnetita , Arginina Deiminasa Proteína-Tipo 4 , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Enzimas Inmovilizadas/antagonistas & inhibidores , Nanopartículas de Magnetita/química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Arginina Deiminasa Proteína-Tipo 4/antagonistas & inhibidores , Arginina Deiminasa Proteína-Tipo 4/metabolismo , Arginina Deiminasa Proteína-Tipo 4/química , Humanos , Medicina Tradicional China , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Evaluación Preclínica de Medicamentos
18.
Se Pu ; 42(7): 711-720, 2024 Jul.
Artículo en Chino | MEDLINE | ID: mdl-38966979

RESUMEN

Protein citrullination is an irreversible post-translational modification process regulated by peptidylarginine deiminases (PADs) in the presence of Ca2+. This process is closely related to the occurrence and development of autoimmune diseases, cancers, neurological disorders, cardiovascular and cerebrovascular diseases, and other major diseases. The analysis of protein citrullination by biomass spectrometry confronts great challenges owing to its low abundance, lack of affinity tags, small mass-to-charge ratio change, and susceptibility to isotopic and deamidation interferences. The methods commonly used to study the protein citrullination mainly involve the chemical derivatization of the urea group of the guanine side chain of the peptide to increase the mass-to-charge ratio difference of the citrullinated peptide. Affinity-enriched labels are then introduced to effectively improve the sensitivity and accuracy of protein citrullination by mass spectrometry. 2,3-Butanedione or phenylglyoxal compounds are often used as derivatization reagents to increase the mass-to-charge ratio difference of the citrullinated peptide, and the resulting derivatives have been observed to contain α-dicarbonyl structures. To date, however, no relevant studies on the reactivity of dicarbonyl compounds with citrullinated peptides have been reported. In this study, we determined whether six α-dicarbonyl and two ß-dicarbonyl compounds undergo derivatization reactions with standard citrullinated peptides using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Among the α-dicarbonyl compounds, 2,3-butanedione and glyoxal reacted efficiently with several standard citrullinated peptides, but yielded a series of by-products. Phenylglyoxal, methylglyoxal, 1,2-cyclohexanedione, and 1,10-phenanthroline-5,6-dione also derivated efficiently with standard citrullinated peptides, generating a single derivative. Thus, a new derivatization method that could yield a single derivative was identified. Among the ß-dicarbonyl compounds, 1,3-cyclohexanedione and 2,4-pentanedione successfully reacted with the standard citrullinated peptides, and generated a single derivative. However, their reaction efficiency was very low, indicating that the ß-dicarbonyl compounds are unsuitable for the chemical derivatization of citrullinated peptides. The above results indicate that the α-dicarbonyl structure is necessary for realizing the efficient and specific chemical derivatization of citrullinated peptides. Moreover, the side chains of the α-dicarbonyl structure determine the structure of the derivatives, derivatization efficiency, and generation (or otherwise) of by-products. Therefore, the specific enrichment and precise identification of citrullinated peptides can be achieved by synthesizing α-dicarbonyl structured compounds containing affinity tags. The proposed method enables the identification of citrullinated proteins and their modified sites by MS, thereby providing a better understanding of the distribution of citrullinated proteins in different tissues. The findings will be beneficial for studies on the mechanism of action of citrullinated proteins in a variety of diseases.


Asunto(s)
Citrulinación , Péptidos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Péptidos/química
19.
Natl Sci Rev ; 11(8): nwae116, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39007007

RESUMEN

Flexible multiplexing chips that permit reconfigurable multidimensional channel utilization are indispensable for revolutionary 6G terahertz communications, but the insufficient manipulation capability of terahertz waves prevents their practical implementation. Herein, we propose the first experimental demonstration of a flexible multiplexing chip for terahertz communication by revealing the unique mechanism of topological phase (TP) transition and perseveration in a heterogeneously coupled bilayer valley Hall topological photonic system. The synthetic and individual TPs operated in the coupled and decoupled states enable controllable on-chip modular TP transitions and subchannel switching. Two time-frequency interleaved subchannels support 10- and 12-Gbit/s QAM-16 high-speed data streams along corresponding paths over carriers of 120 and 130 GHz with 2.5- and 3-GHz bandwidths, respectively. This work unlocks interlayer heterogeneous TPs for inspiring ingenious on-chip terahertz-wave regulation, allowing functionality-reconfigurable, compactly integrated and CMOS-compatible chips.

20.
Environ Res ; 259: 119478, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38917931

RESUMEN

The alarming depletion of global inland lakes in recent decades makes it essential to predict water inflow from rivers to lakes (WIRL) trend and unveil the dominant influencing driver, particularly in the context of climate change. The raw time series data contains multiple components (i.e., long-term trend, seasonal periodicity, and random noise), which makes it challenging for traditional machine/deep learning techniques to effectively capture long-term trend information. In this study, a novel FactorConvSTLnet (FCS) method is developed through integrating STL decomposition, convolutional neural networks (CNN), and factorial analysis into a general framework. FCS is more robust in long-term WIRL trend prediction through separating trend information as a modeling predictor, as well as unveiling predominant drivers. FCS is applied to typical inland lakes (the Aral Sea and the Lake Balkhash) in Central Asia, and results indicate that FCS (Nash-Sutcliffe efficiency = 0.88, root mean squared error = 67m³/s, mean relative error = 10%) outperforms the traditional CNN. Some main findings are: (i) during 1960-1990, reservoir water storage (WSR) was the dominant driver for the two lakes, respectively contributing to 71% and 49%; during 1991-2014 and 2015-2099, evaporation (EVAP) would be the dominant driver, with the contribution of 30% and 47%; (ii) climate change would shift the dominant driver from human activities to natural factors, where EVAP and surface snow amount (SNW) have an increasing influence on WIRL; (iii) compared to SSP1-2.6, the SNW contribution would decrease by 26% under SSP5-8.5, while the EVAP contribution would increase by 9%. The findings reveal the main drivers of shrinkage of the inland lakes and provide the scientific basis for promoting regional ecological sustainability.


Asunto(s)
Cambio Climático , Aprendizaje Profundo , Lagos , Lagos/química , Minería de Datos , Monitoreo del Ambiente/métodos
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