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1.
Nano Lett ; 24(20): 6061-6068, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38728017

RESUMO

van der Waals (vdW) superlattices, comprising different 2D materials aligned alternately by weak interlayer interactions, offer versatile structures for the fabrication of novel semiconductor devices. Despite their potential, the precise control of optoelectronic properties with interlayer interactions remains challenging. Here, we investigate the discrepancies between the SnS/TiS2 superlattice (SnTiS3) and its subsystems by comprehensive characterization and DFT calculations. The disappearance of certain Raman modes suggests that the interactions alter the SnS subsystem structure. Specifically, such structural changes transform the band structure from indirect to direct band gap, causing a strong PL emission (∼2.18 eV) in SnTiS3. In addition, the modulation of the optoelectronic properties ultimately leads to the unique phenomenon of thermally activated photoluminescence. This phenomenon is attributed to the inhibition of charge transfer induced by tunable intralayer strains. Our findings extend the understanding of the mechanism of interlayer interactions in van der Waals superlattices and provide insights into the design of high-temperature optoelectronic devices.

2.
Cancer Lett ; 592: 216909, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679407

RESUMO

Natural killer (NK) cells exert an indispensable role in innate immune responses against cancer progression, however NK cell dysfunction has been rarely reported in hepatocellular carcinoma (HCC). This study sought to uncover the immunoregulatory mechanisms of tumor-infiltrating NK cells in HCC. A consensus NK cell-based signature (NKS) was constructed using integrative machine learning algorithms based on multi-omics data of HCC patients. HCC tumors had lower numbers of infiltrating NK cells than para-tumor normal liver tissues. Based on the NK cell-associated genes, the NKS was built for HCC prognostic prediction and clinical utilities. Drug targets and novel compounds were then identified for high-NKS groups. RAC1 was confirmed as the hub gene in the NKS genes. RAC1 was upregulated in HCC tumors and positively correlated with shorter survival time. RAC1 overexpression in NK-92 cells facilitated the cancer-killing capacity by the anticancer cytotoxic effectors and the upregulated NKG2D. The survival time of PDX-bearing mice was also prolonged upon NK-92RAC1 cells. Mechanistically, RAC1 interacted with STAT3 and facilitated its activation, thereby enabling its binding to the promoter region of NKG2D and functioning as a transcriptional regulator in NK-92 via molecular docking, Co-IP assay, CHIP and luciferase experiments. Collectively, our study describes a novel function of RAC1 in potentiating NK cell-mediated cytotoxicity against HCC, highlighting the clinical utilities of NKS score and RAC1high NK cell subset in HCC immunotherapy.


Assuntos
Carcinoma Hepatocelular , Células Matadoras Naturais , Neoplasias Hepáticas , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Fator de Transcrição STAT3 , Proteínas rac1 de Ligação ao GTP , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , Animais , Camundongos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Imunoterapia/métodos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Masculino , Prognóstico , Ensaios Antitumorais Modelo de Xenoenxerto , Feminino
3.
Sensors (Basel) ; 24(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38610242

RESUMO

Current real-time direction judgment systems are inaccurate and insensitive, as well as limited by the sampling rate of analog-to-digital converters. To address this problem, we propose a dynamic real-time direction judgment system based on an integral dual-frequency laser interferometer and field-programmable gate array technology. The optoelectronic signals resulting from the introduction of a phase subdivision method based on the amplitude resolution of the laser interferometer when measuring displacement are analyzed. The proposed system integrates the optoelectronic signals to increase the accuracy of its direction judgments and ensures these direction judgments are made in real time by dynamically controlling the integration time. Several experiments were conducted to verify the performance of the proposed system. The results show that, compared with current real-time direction judgment systems, the proposed system makes accurate judgements during low-speed motions and can update directions within 0.125 cycles of the phase difference change at different speeds. Moreover, a sweep frequency experiment confirmed the system's ability to effectively judge dynamic directions. The proposed system is capable of accurate and real-time directional judgment during low-speed movements of a table in motion.

4.
Ann Intensive Care ; 14(1): 60, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38641687

RESUMO

BACKGROUND: Weaning from invasive mechanical ventilation (MV) is a complex and challenging process that involves multiple pathophysiological mechanisms. A combined ultrasound evaluation of the heart, lungs, and diaphragm during the weaning phase can help to identify risk factors and underlying mechanisms for weaning failure. This study aimed to investigate the accuracy of lung ultrasound (LUS), transthoracic echocardiography (TTE), and diaphragm ultrasound for predicting weaning failure in critically ill patients. METHODS: Patients undergoing invasive MV for > 48 h and who were readied for their first spontaneous breathing trial (SBT) were studied. Patients were scheduled for a 2-h SBT using low-level pressure support ventilation. LUS and TTE were performed prospectively before and 30 min after starting the SBT, and diaphragm ultrasound was only performed 30 min after starting the SBT. Weaning failure was defined as failure of SBT, re-intubation, or non-invasive ventilation within 48 h. RESULTS: Fifty-one patients were included, of whom 15 experienced weaning failure. During the SBT, the global, anterior, and antero-lateral LUS scores were higher in the failed group than in the successful group. Receiver operating characteristic curve analysis showed that the areas under the curves for diaphragm thickening fraction (DTF) and global and antero-lateral LUS scores during the SBT to predict weaning failure were 0.678, 0.719, and 0.721, respectively. There was no correlation between the LUS scores and the average E/e' ratio during the SBT. Multivariate analysis identified antero-lateral LUS score > 7 and DTF < 31% during the SBT as independent predictors of weaning failure. CONCLUSION: LUS and diaphragm ultrasound can help to predict weaning failure in patients undergoing an SBT with low-level pressure support. An antero-lateral LUS score > 7 and DTF < 31% during the SBT were associated with weaning failure.

5.
BMC Cancer ; 24(1): 519, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38654216

RESUMO

BACKGROUND: Uveal melanoma (UVM) is the most common primary intraocular tumor in adults, with a median survival of 4-5 months following metastasis. DNA damage response (DDR) upregulation in UVM, which could be linked to its frequent activation of the PI3K/AKT pathway, contributes to its treatment resistance. We have reported that embryonic stem cell microenvironments (ESCMe) can revert cancer cells to less aggressive states through downregulation of the PI3K signaling, showing promise in modulating the DDR of UVM. METHODS: Since nonhomologous end joining (NHEJ) is the main DNA repair mechanism in UVM, this study utilized gene expression analysis and survival prognosis analysis to investigate the role of NHEJ-related genes in UVM based on public databases. Xenograft mouse models were established to assess the therapeutic potential of ESC transplantation and exposure to ESC-conditioned medium (ESC-CM) on key DNA repair pathways in UVM. Quantitative PCR and immunohistochemistry were used to analyze NHEJ pathway-related gene expression in UVM and surrounding normal tissues. Apoptosis in UVM tissues was evaluated using the TUNEL assay. RESULTS: PRKDC, KU70, XRCC5, LIG4 and PARP1 showed significant correlations with UM progression. High expression of PRKDC and XRCC5 predicted poorer overall survival, while low PARP1 and XRCC6 expression predicted better disease-free survival in UVM patients. ESCMe treatment significantly inhibited the NHEJ pathway transcriptionally and translationally and promoted apoptosis in tumor tissues in mice bearing UVM. Furthermore, ESC transplantation enhanced DDR activities in surrounding normal cells, potentially mitigating the side effects of cancer therapy. Notably, direct cell-to-cell contact with ESCs was more effective than their secreted factors in regulating the NHEJ pathway. CONCLUSIONS: Our results suggest that NHEJ-related genes might serve as prognostic markers and therapeutic targets in UVM. These findings support the therapeutic potential of ESC-based therapy in enhancing UVM sensitivity to radiochemotherapy and improving treatment outcomes while minimizing damage to healthy cells.


Assuntos
Dano ao DNA , Melanoma , Microambiente Tumoral , Neoplasias Uveais , Animais , Humanos , Neoplasias Uveais/genética , Neoplasias Uveais/patologia , Neoplasias Uveais/metabolismo , Neoplasias Uveais/mortalidade , Camundongos , Melanoma/genética , Melanoma/patologia , Melanoma/metabolismo , Melanoma/terapia , Células-Tronco Embrionárias/metabolismo , Reparo do DNA por Junção de Extremidades , Linhagem Celular Tumoral , Apoptose/genética , Regulação Neoplásica da Expressão Gênica , Feminino , Ensaios Antitumorais Modelo de Xenoenxerto , Prognóstico , Masculino , Autoantígeno Ku/metabolismo , Autoantígeno Ku/genética , Transdução de Sinais , Reparo do DNA
6.
Bone Res ; 12(1): 16, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443372

RESUMO

Bone is a mechanosensitive tissue and undergoes constant remodeling to adapt to the mechanical loading environment. However, it is unclear whether the signals of bone cells in response to mechanical stress are processed and interpreted in the brain. In this study, we found that the hypothalamus of the brain regulates bone remodeling and structure by perceiving bone prostaglandin E2 (PGE2) concentration in response to mechanical loading. Bone PGE2 levels are in proportion to their weight bearing. When weight bearing changes in the tail-suspension mice, the PGE2 concentrations in bones change in line with their weight bearing changes. Deletion of cyclooxygenase-2 (COX2) in the osteoblast lineage cells or knockout of receptor 4 (EP4) in sensory nerve blunts bone formation in response to mechanical loading. Moreover, knockout of TrkA in sensory nerve also significantly reduces mechanical load-induced bone formation. Moreover, mechanical loading induces cAMP-response element binding protein (CREB) phosphorylation in the hypothalamic arcuate nucleus (ARC) to inhibit sympathetic tyrosine hydroxylase (TH) expression in the paraventricular nucleus (PVN) for osteogenesis. Finally, we show that elevated PGE2 is associated with ankle osteoarthritis (AOA) and pain. Together, our data demonstrate that in response to mechanical loading, skeletal interoception occurs in the form of hypothalamic processing of PGE2-driven peripheral signaling to maintain physiologic bone homeostasis, while chronically elevated PGE2 can be sensed as pain during AOA and implication of potential treatment.


Assuntos
Interocepção , Osteoartrite , Animais , Camundongos , Dinoprostona , Tornozelo , Encéfalo , Dor
7.
Foods ; 13(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38540870

RESUMO

Enzyme-assisted ultrasonic extraction (EAUE) was utilized and optimized for extracting polysaccharides from Schizochytrium limacinum meal (SLMPs) via the response surface methodology. The optimal EAUE conditions were determined as follows: enzyme concentration at 5.18%, ultrasonic temperature at 53 °C, ultrasonic duration of 40 min, ultrasonic power at 60 W, and a liquid-to-material ratio of 34 mL/g, achieving a polysaccharide extraction yield of 11.86 ± 0.61%. The purified polysaccharide component, SLMP1-1, isolated using DEAE Sepharose Fast Flow and Sephadex G-100 columns, exhibited potent antioxidant activity. SLMP1-1, with a molecular weight of 25.5 kDa, comprises glucose, mannose, arabinose, and galactose in a molar ratio of 16.39:14.75:1:693.03. 1H NMR analysis revealed the α configuration of SLMP1-1. Antioxidant assessments, including DPPH, ABTS, and ferric ion reduction assays, were detected with inhibitory values at 21.82-82.98%, 38.21-98.46%, and 3.30-20.30% at 0.2-1.0 mg/mL. This confirmed the effective antioxidant capacity of SLMP1-1, which is notably enhanced post oral and gastric digestion. The findings suggest that polysaccharides extracted from Schizochytrium limacinum meal hold significant promise as natural antioxidants.

8.
Cell Signal ; 117: 111072, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38307306

RESUMO

BACKGROUND: Cuproptosis is a novel form of cell death that exhibits close association with mitochondrial respiration and occurs through distinct mechanisms compared to previously characterized forms of cell death. However, the precise impact of cuproptosis-associated genes (CAGs) on prognosis, immune profiles, and treatment efficacy in hepatocellular carcinomas (HCC) remains poorly understood. METHODS: A comprehensive analysis of CAGs in hepatocellular carcinoma (HCC) prognosis was conducted using genomic data from HCC patients. Consensus clustering analysis was performed to determine molecular subtypes related to cuproptosis in HCC. The single-sample gene set enrichment analysis (ssGSEA) algorithm was applied to quantify the infiltration levels of immune cells, while the "ESTIMATE" package was employed to calculate tumor purity, stromal scores, and immune scores in the tumor microenvironment (TME). Principal component analysis (PCA) algorithm was utilized to construct a risk score related to CAGs. Finally, CCK8, wound healing, Transwell migration/invasion, EDU and xenograft model were employed to explore the potential oncogenic role of MTF1. RESULTS: Three distinct patterns of cuproptosis modification were identified, each associated with unique functional enrichments, clinical characteristics, immune cell infiltration, immune checkpoints, tumor microenvironment (TME), and prognosis. A CAGs-related risk score (Cuscore) was developed to predict prognosis in TCGA and validated in GSE76427 and ICGC datasets. Notably, patients with a low Cuscore had better prognoses and were more likely to benefit from immunotherapy.Additionally, the high Cuscore group in HCC also revealed three potential therapeutic targets (TUBA1B, CDC25B, and CSNK2A1) as well as several therapeutic compounds. Moreover, the experiment measured the expression levels of six prognosis-related CAGs, wherein knockdown of MTF1 exhibited suppression of proliferation, invasion, and migration formation in HCC cell lines. CONCLUSION: The findings have enhanced our comprehension of the cuproptosis characteristics in HCC, and stratification based on CuScore may potentially enhance the prediction of patients' prognosis and facilitate the development of effective and innovative treatment strategies.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Algoritmos , Morte Celular , Linhagem Celular , Microambiente Tumoral/genética , Apoptose
9.
Foods ; 12(24)2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38137229

RESUMO

Inhibiting α-amylase can lower postprandial blood glucose levels and delay glucose absorption, offering an effective approach for the development of antidiabetic diets. In this study, an active constituent with inhibitory activity against α-amylase was isolated and purified by bioassay-guided fractionation from Carya cathayensis Sarg. peel (CCSP). The active constituent was identified by NMR and Q-Exactive Orbitrap Mass Spectrometry as 5-O-p-coumaroylquinic acid (5-CQA). 5-CQA possessed strong inhibitory activity against α-amylase, with an IC50 value of 69.39 µM. In addition, the results of the kinetic study indicated that 5-CQA was a potent, reversible, noncompetitive inhibitor against α-amylase. The findings indicate that 5-CQA derived from CCSP has potential as a novel inhibitor against α-amylase, which can help mitigate postprandial blood sugar spikes, making it suitable for inclusion in antidiabetic diets.

10.
Wideochir Inne Tech Maloinwazyjne ; 18(2): 328-342, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37680724

RESUMO

Introduction: The impact of severe hydronephrosis on the outcomes of minimally invasive percutaneous nephrolithotomy (MPCNL) remains controversial; it is still a subject well worth exploration. Aim: To investigate the effects of severe hydronephrosis on surgical outcomes of MPCNL, especially on operative time (OT) and stone-free rate (SFR). Material and methods: In total, 301 patients who underwent MPCNL were included in this study and divided into 4 groups according to the degree of hydronephrosis (nil, mild, moderate, and severe hydronephrosis, respectively). Univariate analyses and multivariate logistic analyses were used to determine the risk factors affecting OT and SFR. Results: Patients with severe hydronephrosis had a longer OT (p < 0.001), a decreased SFR (p < 0.001), and a higher postoperative haemoglobin drop and blood transfusion rate compared to the other 3 cohorts (p = 0.011 and p = 0.043, respectively). Univariate analyses determined that severe hydronephrosis, calyx for access, stone location, stone type, stone size, and number of tracts significantly correlated with OT, while severe hydronephrosis, stone location, stone type, and stone size showed a strong association with SFR (all p < 0.05). Multivariate analyses further identified that severe hydronephrosis (OR = 3.496, p = 0.013), stone location (≥ 4 calyces: OR = 3.024, p = 0.017), stone type (staghorn: OR = 5.204, p = 0.002), and stone size (≥ 1600 mm2: OR = 12.669, p < 0.001; 800-1599 mm2: OR = 5.194, p < 0.001) were significant risk factors affecting OT, while SFR was independently influenced by stone type (staghorn: OR = 4.377, p = 0.039; multiple: OR = 3.778, p = 0.044), stone location (≥ 4 calyces: OR = 4.413, p = 0.020; 2-3 calyces: OR = 3.617, p = 0.034), and severe hydronephrosis (OR = 7.093, p = 0.001). Conclusions: Severe hydronephrosis is a significant risk factor that can lead to longer OT and lower SFR, and correlates with increased risk of bleeding and blood transfusion rate in some cases during MPCNL. Accordingly, severe hydronephrosis is an influential factor that should not be ignored when performing MPCNL.

11.
Opt Express ; 31(18): 29255-29270, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710730

RESUMO

To improve the measurement accuracy of interferometer displacement measurement systems, this study analyzes the characteristics of the interference signal to identify sources of nonlinear errors and develops compensation strategies. Specifically, a model is established for the nonlinear errors of the interferometer, which can be attributed to a laser and polarizing beam splitter (PBS). Following that, the dual orthogonal lock-in amplification algorithm is used to separate and compensate for the frequency uncertainty and amplitude errors. Additionally, a real-time compensation algorithm based on ellipse fitting is proposed to compensate for errors caused by the PBS and the uncertainty of amplitude caused by the light source. Experimental results demonstrate that the peak-to-peak value of the compensated nonlinear error is reduced from 11.62 nm to 5.37 nm.

12.
Entropy (Basel) ; 25(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37238547

RESUMO

The Internet of Vehicles (IoV) enables vehicular data services and applications through vehicle-to-everything (V2X) communications. One of the key services provided by IoV is popular content distribution (PCD), which aims to quickly deliver popular content that most vehicles request. However, it is challenging for vehicles to receive the complete popular content from roadside units (RSUs) due to their mobility and the RSUs' constrained coverage. The collaboration of vehicles via vehicle-to-vehicle (V2V) communications is an effective solution to assist more vehicles to obtain the entire popular content at a lower time cost. To this end, we propose a multi-agent deep reinforcement learning (MADRL)-based popular content distribution scheme in vehicular networks, where each vehicle deploys an MADRL agent that learns to choose the appropriate data transmission policy. To reduce the complexity of the MADRL-based algorithm, a vehicle clustering algorithm based on spectral clustering is provided to divide all vehicles in the V2V phase into groups, so that only vehicles within the same group exchange data. Then the multi-agent proximal policy optimization (MAPPO) algorithm is used to train the agent. We introduce the self-attention mechanism when constructing the neural network for the MADRL to help the agent accurately represent the environment and make decisions. Furthermore, the invalid action masking technique is utilized to prevent the agent from taking invalid actions, accelerating the training process of the agent. Finally, experimental results are shown and a comprehensive comparison is provided, which demonstrates that our MADRL-PCD scheme outperforms both the coalition game-based scheme and the greedy strategy-based scheme, achieving a higher PCD efficiency and a lower transmission delay.

13.
Front Bioeng Biotechnol ; 11: 1152067, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37122864

RESUMO

Background: Cardiovascular and cerebrovascular diseases are major global health problems, and the main cause is atherosclerosis. Recently, molecular imaging has been widely employed in the diagnosis and therapeutic applications of a variety of diseases, including atherosclerosis. Substantive facts have announced that molecular imaging has broad prospects in the early diagnosis and targeted treatment of atherosclerosis. Objective: We conducted a scientometric analysis of the scientific publications over the past 23 years on molecular imaging research in atherosclerosis, so as to identify the key progress, hotspots, and emerging trends. Methods: Original research and reviews regarding molecular imaging in atherosclerosis were retrieved from the Web of Science Core Collection database. Microsoft Excel 2021 was used to analyze the main findings. CiteSpace, VOSviewer, and a scientometric online platform were used to perform visualization analysis of the co-citation of journals and references, co-occurrence of keywords, and collaboration between countries/regions, institutions, and authors. Results: A total of 1755 publications were finally included, which were published by 795 authors in 443 institutions from 59 countries/regions. The United States was the top country in terms of the number and centrality of publications in this domain, with 810 papers and a centrality of 0.38, and Harvard University published the largest number of articles (182). Fayad, ZA was the most productive author, with 73 papers, while LIBBY P had the most co-citations (493). CIRCULATION was the top co-cited journal with a frequency of 1,411, followed by ARTERIOSCL THROM VAS (1,128). The co-citation references analysis identified eight clusters with a well-structured network (Q = 0.6439) and highly convincing clustering (S = 0.8865). All the studies calculated by keyword co-occurrence were divided into five clusters: "nanoparticle," "magnetic resonance imaging," "inflammation," "positron emission tomography," and "ultrasonography". Hot topics mainly focused on cardiovascular disease, contrast media, macrophage, vulnerable plaque, and microbubbles. Sodium fluoride ⁃PET, targeted drug delivery, OCT, photoacoustic imaging, ROS, and oxidative stress were identified as the potential trends. Conclusion: Molecular imaging research in atherosclerosis has attracted extensive attention in academia, while the challenges of clinical transformation faced in this field have been described in this review. The findings of the present research can inform funding agencies and researchers toward future directions.

14.
Nano Lett ; 23(7): 3070-3077, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36995751

RESUMO

Triggered by the expanding demands of semiconductor devices, strain engineering of two-dimensional transition metal dichalcogenides (TMDs) has garnered considerable research interest. Through steady-state measurements, strain has been proved in terms of its modulation of electronic energy bands and optoelectronic properties in TMDs. However, the influence of strain on the spin-orbit coupling as well as its related valley excitonic dynamics remains elusive. Here, we demonstrate the effect of strain on the excitonic dynamics of monolayer WS2 via steady-state fluorescence and transient absorption spectroscopy. Combined with theoretical calculations, we found that tensile strain can reduce the spin-splitting value of the conduction band and lead to transitions between different exciton states via spin-flip mechanism. Our findings suggest that the spin-flip process is strain-dependent, provides a reference for application of valleytronic devices, where tensile strain is usually existing during their design and fabrication.

15.
Ying Yong Sheng Tai Xue Bao ; 34(1): 203-212, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36799395

RESUMO

Soil microorganisms play an important role in the biogeochemical cycles of terrestrial ecosystems. How-ever, it is still unclear how the amount and duration of nitrogen (N) addition affect soil microbial community structure and whether there is a correlation between the changes in microbial community structure and their nutrient limi-tation status. In this study, we conducted an N addition experiment in a subtropical Pinus taiwanensis forest to simulate N deposition with three treatments: control (CK, 0 kg N·hm-2·a-1), low N (LN, 40 kg N·hm-2·a-1), and high N (HN, 80 kg N·hm-2·a-1). Basic soil physicochemical properties, phospholipid fatty acids content, and carbon (C), N and phosphorus (P) acquisition enzyme activities were measured after one and three years of N addition. The relative nutrient limitation status of soil microorganisms was analyzed using ecological enzyme stoichiometry. The results showed that one-year N addition did not affect soil microbial community structure. Three-year LN treatment significantly increased the contents of Gram-positive bacteria (G+), Gram-negative bacteria (G-), actinomycetes (ACT), and total phospholipid fatty acids (TPLFA), whereas three-year HN treatment did not significantly affect soil microbial community, indicating that bacteria and ACT might be more sensitive to N addition. Nitrogen addition exacerbated soil C and P limitation. Phosphorus limitation was the optimal explanatory factor for the changes in soil microbial community structure. It suggested that P limitation induced by N addition might be more beneficial for the growth of certain oligotrophic bacteria (e.g. G+) and the microorganisms participating in the P cycling (e.g. ACT), with consequences on soil microbial community structure of subtropical Pinus taiwanensis forest.


Assuntos
Microbiota , Pinus , Fósforo , Nitrogênio/análise , Solo/química , Biomassa , Microbiologia do Solo , Florestas , Fosfolipídeos , Ácidos Graxos , Bactérias , Carbono , China
16.
Ying Yong Sheng Tai Xue Bao ; 33(10): 2619-2627, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36384595

RESUMO

Priming effect (PE) plays an important role in regulating terrestrial soil carbon (C) cycling, but the impact of different C addition modes on the PE in subtropical forest ecosystems with increasing nitrogen (N) deposition is unclear. In this study, we investigated the effects of C addition patterns (single or repeated C addition) on soil PE by adding 13C-labeled glucose for 90 d in an incubation experiment with different levels of N application (0, 20, and 80 kg N·hm-2·a-1). The different patterns of glucose addition significantly increased soil organic C (SOC) mineralization and produced positive PE. Single glucose addition resulted in stronger PE than repeated addition. PE was significantly weakened with increasing N application levels, indicating that N deposition inhibited soil excitation in Phyllostachys edulis forests. The cumulative PE was significantly negatively correlated with ß-N-acetylaminoglucosidase (NAG) and peroxidase (PEO) activities, and was significantly positively correlated with microbial biomass P (MBP) and potential of hydrogen (pH). Our findings indicated that, when acting together on soil, N application and C addition could strongly affect soil C stocks by stimulating the mineralization of native soil organic matter in subtropical forests. The findings further indicated that single C addition model might overestimate the effect of exogenous readily decomposable organic C on PE and ignore the effect of N deposition on PE, which in turn would overestimate the mineralization loss of forest SOC.


Assuntos
Carbono , Solo , Nitrogênio/farmacologia , Ecossistema , Florestas , Poaceae , Glucose
17.
Ying Yong Sheng Tai Xue Bao ; 33(10): 2611-2618, 2022 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-36384594

RESUMO

As an important parameter regulating soil carbon mineralization, microbial carbon use efficiency (CUE) is essential for the understanding of carbon (C) cycle in terrestrial ecosystems. Three nitrogen supplemental levels, including control (0 kg N·hm-2·a-1), low nitrogen (40 kg N·hm-2·a-1), and high nitrogen (80 kg N·hm-2·a-1), were set up in a Castanopsis fabri forest in the Daiyun Mountain. The basic physical and chemical properties, organic carbon fractions, microbial biomass, and enzyme activities of the soil surface layer (0-10 cm) were measured. To examine the effects of increasing N deposition on microbial CUE and its influencing factors, soil microbial CUE was measured by the 18O-labelled-water approach. The results showed that short-term N addition significantly reduced microbial respiration rate and the activities of C and N acquisition enzymes, but significantly increased soil microbial CUE. ß-N-acetyl amino acid glucosidase (NAG)/microbial biomass carbon (MBC), microbial respiration rate, ß-glucosidase (BG)/MBC, cellulose hydrolase (CBH)/MBC, and soil organic carbon content were the main factors affecting CUE. Moreover, CUE significantly and negatively correlated with NAG/MBC, microbial respiration rate, BG/MBC, and CBH/MBC, but significantly and positively correlated with soil organic carbon. In summary, short-term N addition reduced the cost of soil microbial acquisition of C and N and microbial respiration, and thus increased soil microbial CUE, which would increase soil carbon sequestration potential of the C. fabri forest.


Assuntos
Carbono , Solo , Solo/química , Nitrogênio/análise , Microbiologia do Solo , Ecossistema , Florestas
18.
BMC Urol ; 22(1): 54, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35387631

RESUMO

OBJECTIVE: To explore the feasibility, safety, and effectiveness of single tract minimally invasive endoscopic combined intrarenal surgery (stmECIRS) in the improved prone frog split-leg position for staghorn stones. METHOD: A total of 83 patients with staghorn stones were retrospectively reviewed between January 2018 and June 2021. According to surgical procedure and position, patients were divided into a group of single tract minimally invasive percutaneous nephroscopy (stmPNL) in the prone position and a group of stmECIRS in the improved prone frog split-leg position (turned to the prone position after preset the flexible ureteroscope sheath in lithotomy position, meanwhile, bend both hips and knees to be frog abduction). Demographic characteristics, laboratory tests, stone characters, surgical information, stone-free rate (SFR), and perioperative complications were observed and analyzed. RESULTS: There were no significant differences in demographic characteristics, changes level of Scr and Hb, stone size, radiation density, length of hospital stay, and operation time between the two groups. One-stage SFR in the stmECIRS group was significantly higher than that in the stmPNL group (84.4% vs. 57.9%) (P = 0.007), only 2 patients required blood transfusion after surgery (P = 0.862), and other postoperative complications were not statistically significant (P = 0.345). CONCLUSIONS: StmECIRS in improved prone frog split-leg position has a higher one-stage SFR than stmPNL for staghorn renal stones, and without complications increased, which is a safe, efficient and feasible treatment.


Assuntos
Cálculos Renais , Nefrostomia Percutânea , Cálculos Coraliformes , Humanos , Cálculos Renais/cirurgia , Perna (Membro) , Nefrostomia Percutânea/métodos , Decúbito Ventral , Estudos Retrospectivos , Cálculos Coraliformes/cirurgia , Resultado do Tratamento
19.
J Cancer ; 13(4): 1214-1228, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281853

RESUMO

Purpose: The interplay of inflammation and immunity affects all stages from tumorigenesis to progression, and even tumor response to therapy. A growing interest has been attracted from the biological function of MICALL2 to its effects on tumor progression. This study was designed to verify whether MICALL2 could be a prognostic biomarker to predict kidney renal clear cell carcinoma (KIRC) progression, inflammation, and immune infiltration within tumor microenvironment (TME). Methods: We firstly analyzed MICALL2 expressions across 33 cancer types from the UCSC Xena database and verified its expression in KIRC through GEPIA platform and GEO datasets. The clinicopathological characteristics were further analyzed based on the median expression. Kaplan-Meier method, univariate and multivariate analyses were applied to compare survival outcomes. ESTIMATE and CIBERSORT algorithms were performed to assess immune infiltration, and a co-expression analysis was conducted to evaluate the correlation between MICALL2 and immunoregulatory genes. Enrichment analysis was finally performed to explore the biological significance of MICALL2. Results: MICALL2 was highly expressed in 16 types of cancers compared with normal tissues. MICALL2 expression increased with advanced clinicopathological parameters and was an independent predictor for poor prognosis in KIRC. Moreover, MICALL2 closely correlated with inflammation-promoting signatures and immune infiltration including T cell exhaustion markers. Consistently, MICALL2 involved in the regulation of signaling pathways associated with tumor immunity, tumor progression, and impaired metabolic activities. Conclusion: MICALL2 can function as a prognostic biomarker mediating inflammation, immune infiltration, and T cell exhaustion within the microenvironment of KIRC.

20.
J Cancer ; 13(4): 1385, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35281870

RESUMO

[This corrects the article DOI: 10.7150/jca.29205.].

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