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1.
J Chem Phys ; 160(17)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38748025

RESUMEN

Determining the correlation between the size of a single quantum dot (QD) and its photoluminescence (PL) properties is a challenging task. In the study, we determine the size of each QD by measuring its absorption cross section, which allows for accurate investigation of size-dependent PL blinking mechanisms and volume scaling of the biexciton Auger recombination at the single-particle level. A significant correlation between the blinking mechanism and QD size is observed under low excitation conditions. When the QD size is smaller than their Bohr diameter, single CsPbI3 perovskite QDs tend to exhibit BC-blinking, whereas they tend to exhibit Auger-blinking when the QD size exceeds their Bohr diameter. In addition, by extracting bright-state photons from the PL intensity trajectories, the effects of QD charging and surface defects on the biexcitons are effectively reduced. This allows for a more accurate measurement of the volume scaling of biexciton Auger recombination in weakly confined CsPbI3 perovskite QDs at the single-dot level, revealing a superlinear volume scaling (τXX,Auger ∝ σ1.96).

2.
Cancer Imaging ; 24(1): 66, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783331

RESUMEN

BACKGROUND: To determine the predictive value of interstitial lung abnormalities (ILA) for epidermal growth factor receptor (EGFR) mutation status and assess the prognostic significance of EGFR and ILA in patients with non-small cell lung cancer (NSCLC). METHODS: We reviewed 797 consecutive patients with a histologically proven diagnosis of primary NSCLC from January 2013 to October 2018. Of these, 109 patients with NSCLC were found to have concomitant ILA. Multivariate logistic regression analysis was used to identify the significant clinical and computed tomography (CT) findings in predicting EGFR mutations. Cox proportional hazard models were used to identify significant prognostic factors. RESULTS: EGFR mutations were identified in 22 of 109 tumors (20.2%). Multivariate analysis showed that the models incorporating clinical, tumor CT and ILA CT features yielded areas under the receiver operating characteristic curve (AUC) values of 0.749, 0.838, and 0.849, respectively. When combining the three models, the independent predictive factors for EGFR mutations were non-fibrotic ILA, female sex, and small tumor size, with an AUC value of 0.920 (95% confidence interval[CI]: 0.861-0.978, p < 0.001). In the multivariate Cox model, EGFR mutations (hazard ratio = 0.169, 95% CI = 0.042-0.675, p = 0.012; 692 days vs. 301 days) were independently associated with extended overall survival compared to the wild-type. CONCLUSION: Non-fibrotic ILA independently predicts the presence of EGFR mutations, and the presence of EGFR mutations rather than non-fibrotic ILA serves as an independent good prognostic factor for patients with NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Receptores ErbB , Enfermedades Pulmonares Intersticiales , Neoplasias Pulmonares , Mutación , Tomografía Computarizada por Rayos X , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Femenino , Masculino , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/mortalidad , Persona de Mediana Edad , Anciano , Pronóstico , Enfermedades Pulmonares Intersticiales/genética , Enfermedades Pulmonares Intersticiales/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Valor Predictivo de las Pruebas , Adulto , Anciano de 80 o más Años
3.
Artículo en Inglés | MEDLINE | ID: mdl-38683705

RESUMEN

Graph neural networks (GNNs) have advanced graph classification tasks, where a global pooling to generate graph representations by summarizing node features plays a critical role in the final performance. Most of the existing GNNs are built with a global average pooling (GAP) or its variants, which however, take no full consideration of node specificity while neglecting rich statistics inherent in node features, limiting classification performance of GNNs. Therefore, this article proposes a novel competitive covariance pooling (CCP) based on observation of graph structures, i.e., graphs generally can be identified by a (small) key part of nodes. To this end, our CCP generates node-level second-order representations to explore rich statistics inherent in node features, which are fed to a competitive-based attention module for effectively discovering key nodes through learning node weights. Subsequently, our CCP aggregates node-level second-order representations in conjunction with node weights by summation to produce a covariance representation for each graph, while an iterative matrix normalization is introduced to consider geometry of covariances. Note that our CCP can be flexibly integrated with various GNNs (namely CCP-GNN) to improve the performance of graph classification with little computational cost. The experimental results on seven graph-level benchmarks show that our CCP-GNN is superior or competitive to state-of-the-arts. Our code is available at https://github.com/Jillian555/CCP-GNN.

4.
Physiol Behav ; 279: 114545, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38580203

RESUMEN

Oxytocin is a peptide released into brain regions associated with the processing of aversive memory and threat responses. Given the expression of oxytocin receptors across this vigilance surveillance system of the brain, we investigated whether pharmacological antagonism of the receptor would impact contextual aversive conditioning and memory. Adult male rats were conditioned to form an aversive contextual memory. The effects of peripheral administration of either the competitive antagonist Atosiban or noncompetitive antagonist L-368,899 were compared to saline controls. Oxytocin receptor antagonism treatment did not significantly impact the consolidation of aversive contextual memory in any of the groups. We conclude that peripheral antagonism of oxytocin signalling did not impact the formation of aversive memory.


Asunto(s)
Consolidación de la Memoria , Receptores de Oxitocina , Ratas , Masculino , Animales , Oxitocina/farmacología , Miedo/fisiología , Condicionamiento Psicológico/fisiología
5.
Comput Methods Programs Biomed ; 249: 108145, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38582038

RESUMEN

BACKGROUND AND OBJECTIVE: Obstetricians use Cardiotocography (CTG), which is the continuous recording of fetal heart rate and uterine contraction, to assess fetal health status. Deep learning models for intelligent fetal monitoring trained on extensively labeled and identically distributed CTG records have achieved excellent performance. However, creation of these training sets requires excessive time and specialist labor for the collection and annotation of CTG signals. Previous research has demonstrated that multicenter studies can improve model performance. However, models trained on cross-domain data may not generalize well to target domains due to variance in distribution among datasets. Hence, this paper conducted a multicenter study with Deep Semi-Supervised Domain Adaptation (DSSDA) for intelligent interpretation of antenatal CTG signals. This approach helps to align cross-domain distribution and transfer knowledge from a label-rich source domain to a label-scarce target domain. METHODS: We proposed a DSSDA framework that integrated Minimax Entropy and Domain Invariance (DSSDA-MMEDI) to reduce inter-domain gaps and thus achieve domain invariance. The networks were developed using GoogLeNet to extract features from CTG signals, with fully connected, softmax layers for classification. We designed a Dynamic Gradient-driven strategy based on Mutual Information (DGMI) to unify the losses from Minimax Entropy (MME), Domain Invariance (DI), and supervised cross-entropy during iterative learning. RESULTS: We validated our DSSDA model on two datasets collected from collaborating healthcare institutions and mobile terminals as the source and target domains, which contained 16,355 and 3,351 CTG signals, respectively. Compared to the results achieved with deep learning networks without DSSDA, DSSDA-MMEDI significantly improved sensitivity and F1-score by over 6%. DSSDA-MMEDI also outperformed other state-of-the-art DSSDA approaches for CTG signal interpretation. Ablation studies were performed to determine the unique contribution of each component in our DSSDA mechanism. CONCLUSIONS: The proposed DSSDA-MMEDI is feasible and effective for alignment of cross-domain data and automated interpretation of multicentric antenatal CTG signals with minimal annotation cost.


Asunto(s)
Cardiotocografía , Monitoreo Fetal , Embarazo , Femenino , Humanos , Cardiotocografía/métodos , Entropía , Monitoreo Fetal/métodos , Contracción Uterina , Frecuencia Cardíaca Fetal/fisiología
6.
Int J Dermatol ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38682296

RESUMEN

BACKGROUND: Our aim was to target the unsatisfied need for early detection of the at-risk population and determine the subgroup of patients whose psoriasis (PsO) could transform into psoriatic arthritis (PsA). METHODS: A retrospective and longitudinal case-control study was conducted at Beijing Chao-yang Hospital. It included 75 patients who were clinically diagnosed with PsA in the case group and 345 who solely suffered from PsO without PsA in the control group. A variety of baseline covariates were gathered from every patient with PsO. Univariate and multivariate analyses and receiver operating characteristic (ROC) curves were used to identify underlying risk factors and determine whether it was necessary to examine the imaging of PsO patients. RESULTS: In multivariate logistic regression analysis, age ≥40 (odds ratio (OR): 1.04, 95% confidence interval (CI): 1.02-1.06, P < 0.01), nail involvement (OR: 1.17, 95% CI: 1.09-1.32, P < 0.01), erythrocyte sedimentation rate (ESR) (OR: 1.03, 95% CI: 1.01-1.06, P < 0.05) and elevated high-sensitivity C-reactive protein (hs-CRP) (OR: 1.31, 95% CI: 1.13-1.53, P < 0.01) were perceived to be risk factors for the transformation from PsO into clinical PsA. By combining magnetic resonance imaging (MRI)-detected enthesitis with tenosynovitis, combined predictors demonstrated better diagnostic efficacy, with an improvement in specificity (94.3% vs. 69%) and similarities in sensitivity (89% vs. 84.6%). The areas under the ROC curve (AUCs) amounted to 0.925 (95% CI: 0.882-0.967, P < 0.01) and 0.858 (95% CI: 0.814-0.903, P < 0.01). CONCLUSIONS: It was identified that age ≥40, nail involvement, as well as an elevated ESR, and hs-CRP served as independent risk factors for PsO transforming into PsA. Additionally, MRI provides additional value for the early recognition of PsA.

7.
Adv Sci (Weinh) ; : e2308597, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664984

RESUMEN

The development of semi-artificial photosynthetic systems, which integrate metal-organic frameworks (MOFs) with industrial microbial cell factories for light-driven synthesis of fuels and valuable chemicals, represents a highly promising avenue for both research advancements and practical applications. In this study, an MOF (PCN-222) utilizing racemic-(4-carboxyphenyl) porphyrin and zirconium chloride (ZrCl4) as primary constituents is synthesized. Employing a self-assembly process, a hybrid system is constructed, integrating engineered Escherichia coli (E. coli) to investigate light-driven hydrogen and lysine production. These results demonstrate that the light-irradiated biohybrid system efficiently produce H2 with a quantum efficiency of 0.75% under full spectrum illumination, the elevated intracellular reducing power NADPH is also observed. By optimizing the conditions, the biohybrid system achieves a maximum lysine production of 18.25 mg L-1, surpassing that of pure bacteria by 332%. Further investigations into interfacial electron transfer mechanisms reveals that PCN-222 efficiently captures light and facilitates the transfer of photo-generated electrons into E. coli cells. It is proposed that the interfacial energy transfer process is mediated by riboflavin, with facilitation by secreted small organic acids acting as hole scavengers for PCN-222. This study establishes a crucial foundation for future research into the light-driven biomanufacturing using E. coli-based hybrid systems.

8.
Nano Lett ; 24(15): 4362-4368, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38488060

RESUMEN

Environmentally friendly, ultrafast display pixels of micrometer sizes are fabricated with nanometer-thick gold films and Si/SiO2 wafers. The color displayed is due to both the plasmon response of the gold film and the optical interference from the Fabry-Peerot cavity formed by the underlying silicon substrate, the semitransparent gold film and the air gap between them. When an electric potential is applied to the gold film, the electrostatic force induces an attraction between the gold film and the silicon wafer. Due to the flexibility of the film, the size of the air gap changes, resulting in a changing color. By applying different driving signals, we have achieved cyan, magenta, and yellow reflected colors. The maximum switching rate of the pixel is primarily determined by the thickness dependence of the metal drum and its Young's modulus and is typically in the MHz regime.

9.
Small ; : e2311984, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38461526

RESUMEN

A major issue with Fenton-like reaction is the excessive consumption of H2 O2 caused by the sluggish regeneration rate of low-valent metal, and how to improve the activation efficiency of H2 O2 has become a key in current research. Herein, a nano-heterostructure catalyst (1.0-MnCu/C) based on nano-interface engineering is constructed by supporting Cu and MnO on carbon skeleton, and its kinetic rate for the degradation of tetracycline hydrochloride is 0.0436 min-1 , which is 2.9 times higher than that of Cu/C system (0.0151 min-1 ). The enhancement of removal rate results from the introduced Mn species can aggregate and transfer electrons to Cu sites through the electron bridge Mn-N/O-Cu, thus preventing Cu2+ from oxidizing H2 O2 to form O2 •- , and facilitating the reduction of Cu2+ and generating more reactive oxygen species (1 O2 and ·OH) with stronger oxidation ability, resulting in H2 O2 utilization efficiency is 1.9 times as much as that of Cu/C. Additionally, the good and stable practical application capacity in different bodies demonstrates that it has great potential for practical environmental remediation.

10.
Poult Sci ; 103(4): 103533, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38359770

RESUMEN

Artificial insemination (AI) technology has greatly promoted the development of the chicken industry. Recently, AI technology has also begun to be used in the duck industry, but there are some problems. Numerous researchers have shown that microbes colonizing in semen can degrade semen quality, and AI can increase the harmful microbial load in hen's reproductive tract. Different from the degraded external genitalia of roosters, drakes have well-developed external genitalia, which may cause drake semen to be more susceptible to microbial contamination. However, information on the compositions, sources, and effects of semen microbes on semen quality remains unknown in drakes. In the current study, high-throughput sequencing technology was used to detect microbial communities in drake semen, environmental swabs, cloacal swabs, and the spermaduct after quantifying the semen quality of drakes to investigate the effects of microbes in the environment, cloaca, and spermaduct on semen microbiota and the relationships between semen microbes and semen quality. Taxonomic analysis showed that the microbes in the semen, environment, cloaca, and spermaduct samples were all classified into 4 phyla and 25 genera. Firmicutes and Proteobacteria were the dominant phyla. Phyllobacterium only existed in the environment, while Marinococcus did not exist in the cloaca. Of the 24 genera present in semen: Brachybacterium, Brochothrix, Chryseobacterium, Kocuria, Marinococcus, Micrococcus, Rothia, Salinicoccus, and Staphylococcus originated from the environment; Achromobacter, Aerococcus, Corynebacterium, Desemzia, Enterococcus, Jeotgalicoccus, Pseudomonas, Psychrobacter, and Turicibacter originated from the cloaca; and Agrobacterium, Carnobacterium, Chelativorans, Devosia, Halomonas, and Oceanicaulis originated from the spermaduct. In addition, K-means clustering analysis showed that semen samples could be divided into 2 clusters based on microbial compositions, and compared with cluster 1, the counts of Chelativorans (P < 0.05), Devosia (P < 0.01), Halomonas (P < 0.05), and Oceanicaulis (P < 0.05) were higher in cluster 2, while the sperm viability (P < 0.05), total sperm number (P < 0.01), and semen quality factor (SQF) (P < 0.01) were lower in cluster 2. Furthermore, functional prediction analysis of microbes showed that the activities of starch and sucrose metabolism, phosphotransferase system, ABC transporters, microbial metabolism in diverse environments, and quorum sensing pathways between cluster 1 and cluster 2 were significantly different (P < 0.05). Overall, environmental/cloacal microbes resulted in semen contamination, and microbes from the Chelativorans, Devosia, Halomonas, and Oceanicaulis genera may have negative effects on semen quality in drakes by affecting the activities of starch and sucrose metabolism, phosphotransferase system, ABC transporters, and quorum sensing pathways that are associated with carbohydrate metabolism. These data will provide a basis for developing strategies to prevent microbial contamination of drake semen.


Asunto(s)
Pollos , Análisis de Semen , Masculino , Animales , Femenino , Análisis de Semen/veterinaria , Semillas , Transportadoras de Casetes de Unión a ATP , Fosfotransferasas , Almidón , Sacarosa
11.
Cereb Cortex ; 34(2)2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38306660

RESUMEN

Using event-related potentials, this study examined how self-esteem affects neural responses to competence (interpersonal) feedback when the need for relatedness (competence) is thwarted or met. Participants with low and high self-esteem acted as advisors who selected one of two options for a putative advisee. Subsequently, they passively observed the advisee, accepted, or rejected their advice (i.e. interpersonal feedback) and received correct or incorrect outcomes (i.e. competence feedback). When interpersonal feedback was followed by competence feedback, high self-esteem participants showed a smaller P3 following incorrect than correct outcomes, irrespective of whether the advice had been accepted or rejected. However, low self-esteem participants showed this P3 effect only when the advice was rejected, and the P3 difference disappeared when the advice was accepted. When competence feedback was followed by interpersonal feedback, both low self-esteem and high self-esteem individuals showed a larger P2 for rejection than for acceptance and a larger late potential component for incorrect than correct outcomes. These findings suggest that when interpersonal feedback is followed by competence feedback, low self-esteem and high self-esteem individuals have a desire for self-positivity. When competence feedback is followed by interpersonal feedback, they may have motives for self-change. Our findings shed light on the motivational mechanisms for self-esteem and feedback.


Asunto(s)
Relaciones Interpersonales , Autoimagen , Humanos , Motivación
12.
Waste Manag ; 177: 169-176, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38325017

RESUMEN

Chemical looping gasification (CLG) is a promising technology that utilizes lattice oxygen for partial oxidation of solid organic waste to produce high-quality syngas. The utilization of low-cost and high-performance oxygen carriers (OCs) is important for the success of this technology. The red mud from aluminum production was mixed with calcium and manganese oxides to prepare CaMn0.5Fe0.5O3-δ perovskite OCs. The comparative redox tests were carried out to analyze the reactivity using a thermogravimetric analyzer (TGA). Multiple cycle CLG experiments were conducted on a wet municipal sludge in a lab-scale fluidized bed to produce the hydrogen-rich gas. The results showed that the CaMn0.5Fe0.5O3-δ-washed demonstrated higher oxygen transfer capacity and better cycling stability with a maximum weight loss of 7.3096 %. After the 5th cycle in CLG, the syngas obtained using CaMn0.5Fe0.5O3-δ-washed maintained a H2 volume fraction exceeding 40%. However, an increase in CO2 production was also observed, which could be due to the catalytic effect of MnO in the OC on the steam-reforming reaction. The XRD curves showed that fresh CaMn0.5Fe0.5O3-δ-washed exhibited prominent diffraction peaks characteristic of perovskite. It was observed that after undergoing 5 cycles, the presence of iron calcium silicate structures containing Mn became evident due to the attachment of sludge ash, leading to the increased impurities on the surface of OCs with a decrease in the specific surface area. Additionally, some of the reacted OC particles exhibited a hollow structure, facilitating the fluidization. This preliminary study provides the basis for the improvement of the OC performance in sludge gasification.


Asunto(s)
Compuestos de Calcio , Óxidos , Aguas del Alcantarillado , Titanio , Aluminio , Oxígeno , Residuos Sólidos
13.
Front Microbiol ; 15: 1342839, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38362498

RESUMEN

Background: Streptococcus pneumoniae is a common pathogen that colonizes the human upper respiratory tract, causing high morbidity and mortality worldwide. This study aimed to investigate the prevalence status of S. pneumoniae isolated from patients of all ages in Southwest China, including serotype, antibiotic susceptibility and other molecular characteristics, to provide a basis for clinical antibiotic usage and vaccine development. Methods: This study was conducted from January 2018 to March 2022 at West China Hospital, West China Second University Hospital, First People's Hospital of Longquanyi District (West China Longquan Hospital), Meishan Women and Children's Hospital (Alliance Hospital of West China Second University Hospital) and Chengdu Jinjiang Hospital for Women and Children Health. Demographic and clinical characteristics of 263 pneumococcal disease (PD) all-age patients were collected and analyzed. The serotypes, sequence types (STs), and antibiotic resistance of the strains were determined by next-generation sequencing, sequence analysis and the microdilution broth method. Results: The most common pneumococcal serotypes were 19F (17.87%), 19A (11.41%), 3 (8.75%), 23F (6.46%) and 6A (5.70%). Coverage rates for PCV10, PCV13, PCV15, PCV20 and PCV24 were 36.12, 61.98, 61.98, 63.12 and 64.26%, respectively. Prevalent STs were ST271 (12.55%), ST320 (11.79%), ST90 (4.18%), ST876 (4.18%) and ST11972 (3.42%). Penicillin-resistant S. pneumoniae (PRSP) accounted for 82.35 and 1.22% of meningitis and nonmeningitis PD cases, respectively. Resistance genes msrD (32.7%), mefA (32.7%), ermB (95.8%), tetM (97.3%) and catTC (7.6%) were found among 263 isolates. Most isolates showed high resistance to erythromycin (96.96%) and tetracycline (79.85%), with more than half being resistant to SXT (58.94%). A few isolates were resistant to AMX (9.89%), CTX (11.03%), MEN (9.13%), OFX (1.14%), LVX (1.14%) and MXF (0.38%). All isolates were susceptible to vancomycin and linezolid. Conclusion: Our study provides reliable information, including the prevalence, molecular characterization and antimicrobial resistance of S. pneumoniae isolates causing pneumococcal diseases in Southwest China. The findings contribute to informed and clinical policy decisions for prevention and treatment.

14.
Sensors (Basel) ; 24(3)2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38339617

RESUMEN

Across five studies, we present the preliminary technical validation of an infant-wearable platform, LittleBeats™, that integrates electrocardiogram (ECG), inertial measurement unit (IMU), and audio sensors. Each sensor modality is validated against data from gold-standard equipment using established algorithms and laboratory tasks. Interbeat interval (IBI) data obtained from the LittleBeats™ ECG sensor indicate acceptable mean absolute percent error rates for both adults (Study 1, N = 16) and infants (Study 2, N = 5) across low- and high-challenge sessions and expected patterns of change in respiratory sinus arrythmia (RSA). For automated activity recognition (upright vs. walk vs. glide vs. squat) using accelerometer data from the LittleBeats™ IMU (Study 3, N = 12 adults), performance was good to excellent, with smartphone (industry standard) data outperforming LittleBeats™ by less than 4 percentage points. Speech emotion recognition (Study 4, N = 8 adults) applied to LittleBeats™ versus smartphone audio data indicated a comparable performance, with no significant difference in error rates. On an automatic speech recognition task (Study 5, N = 12 adults), the best performing algorithm yielded relatively low word error rates, although LittleBeats™ (4.16%) versus smartphone (2.73%) error rates were somewhat higher. Together, these validation studies indicate that LittleBeats™ sensors yield a data quality that is largely comparable to those obtained from gold-standard devices and established protocols used in prior research.


Asunto(s)
Postura , Caminata , Adulto , Humanos , Movimiento (Física) , Caminata/fisiología , Postura/fisiología , Posición de Pie , Algoritmos , Fenómenos Biomecánicos
15.
Phys Chem Chem Phys ; 26(7): 6256-6264, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38305726

RESUMEN

Finding materials with suitable thermal conductivity (κ) is crucial for improving energy efficiency, reducing carbon emissions, and achieving sustainability. Atomic substitution and structural adjustments are commonly used methods. By comparing the κ of two different structures of two-dimensional (2D) IIIA-nitrides and their corresponding carbides, we explored whether atomic substitution has the same impact on κ in different structures. All eight materials exhibit normal temperature dependence, with κ decreasing as the temperature rises. Both structures are single atomic layers of 2D materials, forming M-N bonds, with the difference being that H-MN consists of hexagonal rings, while T-MN consists of tetragonal and octagonal rings. 2D IIIA-nitrides provide a good illustration of the impact of atomic substitution and structure on κ. On a logarithmic scale of κ, it approximates two parallel lines, indicating that different structures exhibit similar trends of κ reduction under the same conditions of atomic substitution. We analyzed the mechanisms behind the decreasing trend in κ from a phonon mode perspective. The main reason for the decrease in κ is that heavier atoms lower lattice vibrations, reducing phonon frequencies. Electronegativity increases, altering bonding characteristics and increasing anharmonicity. Reduced symmetry in complex structures decreases phonon group velocities and enhances phonon anharmonicity, leading to decreased phonon lifetimes. It's noteworthy that we found that atomic substitution and structure significantly affect hydrodynamic phonon transport as well. Both complex structures and atomic substitution simultaneously reduce the effects of hydrodynamic phonon transport. By comparing the impact of κ on two different structures of 2D IIIA-nitrides and their corresponding carbides, we have deepened our understanding of phonon transport in 2D materials. Heavier atomic substitution and more complex structures result in reduced κ and decreased hydrodynamic phonon transport effects. This research is likely to have a significant impact on the study of micro- and nanoscale heat transfer, including the design of materials with specific heat transfer properties for future applications.

16.
Biochem Biophys Res Commun ; 702: 149652, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38341922

RESUMEN

Prostatic acid phosphatase (PAP) is a glycoprotein that plays a crucial role in the hydrolysis of phosphate ester present in prostatic exudates. It is a well-established indicator for prostate cancer due to its elevated serum levels in disease progression. Despite its abundance in semen, PAP's influence on male fertility has not been extensively studied. In our study, we report a significantly optimized method for purifying human endogenous PAP, achieving remarkably high efficiency and active protein recovery rate. This achievement allowed us to better analyze and understand the PAP protein. We determined the cryo-electron microscopic (Cryo-EM) structure of prostatic acid phosphatase in its physiological state for the first time. Our structural and gel filtration analysis confirmed the formation of a tight homodimer structure of human PAP. This functional homodimer displayed an elongated conformation in the cryo-EM structure compared to the previously reported crystal structure. Additionally, there was a notable 5-degree rotation in the angle between the α domain and α/ß domain of each monomer. Through structural analysis, we revealed three potential glycosylation sites: Asn94, Asn220, and Asn333. These sites contained varying numbers and forms of glycosyl units, suggesting sugar moieties influence PAP function. Furthermore, we found that the active sites of PAP, His44 and Asp290, are located between the two protein domains. Overall, our study not only provide an optimized approach for PAP purification, but also offer crucial insights into its structural characteristics. These findings lay the groundwork for further investigations into the physiological function and potential therapeutic applications of this important protein.


Asunto(s)
Neoplasias de la Próstata , Semen , Humanos , Masculino , Semen/química , Semen/metabolismo , Microscopía por Crioelectrón , Próstata/metabolismo , Fosfatasa Ácida/metabolismo
17.
Obes Facts ; 17(2): 131-144, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38185107

RESUMEN

INTRODUCTION: The present study aimed to investigate whether and how normobaric intermittent hypoxic training (IHT) or remote ischemic preconditioning (RIPC) plus normoxic training (RNT) has a synergistic protective effect on lipid metabolism and vascular function compared with normoxic training (NT) in overweight or obese adults. METHODS: A total of 37 overweight or obese adults (36.03 ± 10.48 years) were randomly assigned to 3 groups: NT group (exercise intervention in normoxia), IHT group (exercise intervention in normobaric hypoxic chamber), and RNT group (exercise intervention in normoxia + RIPC twice daily). All participants carried out the same 1-h exercise intervention for a total of 4 weeks, 5 days per week. Physical fitness parameters were evaluated at pre- and postexercise intervention. RESULTS: After training, all three groups had a significantly decreased body mass index (p < 0.05). The IHT group had reduced body fat percentage, visceral fat mass (p < 0.05), blood pressure (p < 0.01), left ankle-brachial index (ABI), maximal heart rate (HRmax) (p < 0.05), expression of peroxisome proliferator-activated receptor-γ (PPARγ) (p < 0.01) and increased expression of SIRT1 (p < 0.05), VEGF (p < 0.01). The RNT group had lowered waist-to-hip ratio, visceral fat mass, blood pressure (p < 0.05), and HRmax (p < 0.01). CONCLUSION: IHT could effectively reduce visceral fat mass and improve vascular elasticity in overweight or obese individuals than pure NT with the activation of SIRT1-related pathways. And RNT also produced similar benefits on body composition and vascular function, which were weaker than those of IHT but stronger than NT. Given the convenience and economy of RNT, both intermittent hypoxic and ischemic training have the potential to be successful health promotion strategies for the overweight/obese population.


Asunto(s)
Metabolismo de los Lípidos , Sobrepeso , Adulto , Humanos , Homeostasis , Obesidad/terapia , Sobrepeso/terapia , Sirtuina 1
18.
BMC Med ; 22(1): 4, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38166913

RESUMEN

BACKGROUND: We aimed to determine whether and how the combination of acetazolamide and remote ischemic preconditioning (RIPC) reduced the incidence and severity of acute mountain sickness (AMS). METHODS: This is a prospective, randomized, open-label, blinded endpoint (PROBE) study involving 250 healthy volunteers. Participants were randomized (1:1:1:1:1) to following five groups: Ripc (RIPC twice daily, 6 days), Rapid-Ripc (RIPC four times daily, 3 days), Acetazolamide (twice daily, 2 days), Combined (Acetazolamide plus Rapid-Ripc), and Control group. After interventions, participants entered a normobaric hypoxic chamber (equivalent to 4000 m) and stayed for 6 h. The primary outcomes included the incidence and severity of AMS, and SpO2 after hypoxic exposure. Secondary outcomes included systolic and diastolic blood pressure, and heart rate after hypoxic exposure. The mechanisms of the combined regime were investigated through exploratory outcomes, including analysis of venous blood gas, complete blood count, human cytokine antibody array, ELISA validation for PDGF-AB, and detection of PDGF gene polymorphisms. RESULTS: The combination of acetazolamide and RIPC exhibited powerful efficacy in preventing AMS, reducing the incidence of AMS from 26.0 to 6.0% (Combined vs Control: RR 0.23, 95% CI 0.07-0.70, P = 0.006), without significantly increasing the incidence of adverse reactions. Combined group also showed the lowest AMS score (0.92 ± 1.10). Mechanistically, acetazolamide induced a mild metabolic acidosis (pH 7.30 ~ 7.31; HCO3- 18.1 ~ 20.8 mmol/L) and improved SpO2 (89 ~ 91%) following hypoxic exposure. Additionally, thirty differentially expressed proteins (DEPs) related to immune-inflammatory process were identified after hypoxia, among which PDGF-AB was involved. Further validation of PDGF-AB in all individuals showed that both acetazolamide and RIPC downregulated PDGF-AB before hypoxic exposure, suggesting a possible protective mechanism. Furthermore, genetic analyses demonstrated that individuals carrying the PDGFA rs2070958 C allele, rs9690350 G allele, or rs1800814 G allele did not display a decrease in PDGF-AB levels after interventions, and were associated with a higher risk of AMS. CONCLUSIONS: The combination of acetazolamide and RIPC exerts a powerful anti-hypoxic effect and represents an innovative and promising strategy for rapid ascent to high altitudes. Acetazolamide improves oxygen saturation. RIPC further aids acetazolamide, which synergistically regulates PDGF-AB, potentially involved in the pathogenesis of AMS. TRIAL REGISTRATION: ClinicalTrials.gov NCT05023941.


Asunto(s)
Mal de Altura , Precondicionamiento Isquémico , Humanos , Mal de Altura/prevención & control , Mal de Altura/diagnóstico , Acetazolamida , Estudios Prospectivos , Enfermedad Aguda , Hipoxia/prevención & control
19.
Genes (Basel) ; 15(1)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38275602

RESUMEN

Cervical cancer is a widespread malignancy among women, leading to a substantial global health impact. Despite extensive research, our understanding of the basic molecules and pathogenic processes of cervical squamous cell carcinoma is still insufficient. This investigation aims to uncover immune-related genes linked to CESC and delineate their functions. Leveraging data from the GEO and ImmPort databases, a total of 22 immune-related genes were identified. Multiple tools, including DAVID, the human protein atlas, STRING, GeneMANIA, and TCGA, were employed to delve into the expression and roles of these immune genes in CESC, alongside their connections to the disease's pathological features. Through RT-PCR, the study confirmed notable disparities in CXCL8 and CXCL10 mRNA expression between CESC and normal cervical tissue. The TCGA dataset's immune-related information reinforced the association of CXCL8 and CXCL10 with immune infiltration in CESC. This research sheds light on the potential of CXCL8 and CXCL10 as promising therapeutic targets and essential prognostic factors for individuals diagnosed with CESC.


Asunto(s)
Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias del Cuello Uterino , Femenino , Humanos , Neoplasias del Cuello Uterino/genética , Carcinoma de Células Escamosas/genética , Bases de Datos Factuales , Perfil Genético
20.
Nat Struct Mol Biol ; 31(1): 115-124, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38177687

RESUMEN

The subcortical maternal complex (SCMC) plays a crucial role in early embryonic development. Malfunction of SCMC leads to reproductive diseases in women. However, the molecular function and assembly basis for SCMC remain elusive. Here we reconstituted mouse SCMC and solved the structure at atomic resolution using single-particle cryo-electron microscopy. The core complex of SCMC was formed by MATER, TLE6 and FLOPED, and MATER embraced TLE6 and FLOPED via its NACHT and LRR domains. Two core complexes further dimerize through interactions between two LRR domains of MATERs in vitro. FILIA integrates into SCMC by interacting with the carboxyl-terminal region of FLOPED. Zygotes from mice with Floped C-terminus truncation showed delayed development and resembled the phenotype of zygotes from Filia knockout mice. More importantly, the assembly of mouse SCMC was affected by corresponding clinical variants associated with female reproductive diseases and corresponded with a prediction based on the mouse SCMC structure. Our study paves the way for further investigations on SCMC functions during mammalian preimplantation embryonic development and reveals underlying causes of female reproductive diseases related to SCMC mutations, providing a new strategy for the diagnosis of female reproductive disorders.


Asunto(s)
Desarrollo Embrionario , Oocitos , Embarazo , Femenino , Humanos , Ratones , Animales , Microscopía por Crioelectrón , Cigoto , Ratones Noqueados , Mamíferos
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