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1.
Appl Immunohistochem Mol Morphol ; 32(8): 362-370, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39076030

RESUMO

SATB2 has been reported to be highly specific for lower gastrointestinal tract tumors. On the basis of its ileum-colon conversion effects, which involve the activation of colonic genes in cooperation with CDX2 and HNF4A, we hypothesized that SATB2 and CDX2 might define the characteristics of colorectal cancers (CRCs). In the present study, the clinicopathologic and immunohistochemical characteristics of 269 CRCs were analyzed according to SATB2 and CDX2 expression. CRCs with SATB2- and/or CDX2- phenotypes showed associations with poorly differentiated histotypes ( P <0.00001), mucus production ( P =0.0019), and mismatch repair-deficient phenotypes ( P <0.00001). SATB2-/CDX2- CRCs were significantly associated with CK20-negativity, with or without CK7 expression ( P <0.00001), as well as with MUC5AC-positivity ( P <0.00001), and CD10-negativity ( P =0.00047). Negativity for SATB2 or CDX2 was associated with the expression of PD-L1 in both all CRC ( P <0.00001) and mismatch repair-proficient CRC ( P =0.000091). Multivariate Cox hazard regression analysis identified negativity for SATB2 and/or CDX2 as potential independent risk factors for patients with CRC. Regarding the diagnostic utility of SATB2, all of the 44 CRC metastases could be diagnosed as colorectal in origin if the immunohistochemical phenotypes (including CK7, CK20, and p53) of the primary lesions and patient history were considered. Among the other 684 tumors, we were unable to distinguish a case of CK7-/CK20+/CDX2+/SATB2+ ovarian mucinous cystadenocarcinoma from metastatic CRC without the patient history and clinical information.


Assuntos
Fator de Transcrição CDX2 , Neoplasias Colorretais , Imuno-Histoquímica , Proteínas de Ligação à Região de Interação com a Matriz , Fatores de Transcrição , Humanos , Fator de Transcrição CDX2/metabolismo , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Ligação à Região de Interação com a Matriz/metabolismo , Proteínas de Ligação à Região de Interação com a Matriz/genética , Feminino , Masculino , Pessoa de Meia-Idade , Fatores de Transcrição/metabolismo , Idoso , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/genética , Adulto , Idoso de 80 Anos ou mais , Queratina-20/metabolismo , Queratina-20/genética
2.
J Pathol Clin Res ; 10(4): e12386, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38890810

RESUMO

Evidence for the tumour-supporting capacities of the tumour stroma has accumulated rapidly in colorectal cancer (CRC). Tumour stroma is composed of heterogeneous cells and components including cancer-associated fibroblasts (CAFs), small vessels, immune cells, and extracellular matrix proteins. The present study examined the characteristics of CAFs and collagen, major components of cancer stroma, by immunohistochemistry and Sirius red staining. The expression status of five independent CAF-related or stromal markers, decorin (DCN), fibroblast activation protein (FAP), podoplanin (PDPN), alpha-smooth muscle actin (ACTA2), and collagen, and their association with clinicopathological features and clinical outcomes were analysed. Patients with DCN-high tumours had a significantly worse 5-year survival rate (57.3% versus 79.0%; p = 0.044). Furthermore, hierarchical clustering analyses for these five markers identified three groups that showed specific characteristics: a solid group (cancer cell-rich, DCNLowPDPNLow); a PDPN-dominant group (DCNMidPDPNHigh); and a DCN-dominant group (DCNHighPDPNLow), with a significant association with patient survival (p = 0.0085). Cox proportional hazards model identified the PDPN-dominant group (hazard ratio = 0.50, 95% CI = 0.26-0.96, p = 0.037) as a potential favourable factor compared with the DCN-dominant group. Of note, DCN-dominant tumours showed the most advanced pT stage and contained the lowest number of CD8+ and FOXP3+ immune cells. This study has revealed that immunohistochemistry and special staining of five stromal factors with hierarchical clustering analyses could be used for the prognostication of patients with CRC. Cancer stroma-targeting therapies may be candidate treatments for patients with CRC.


Assuntos
Biomarcadores Tumorais , Fibroblastos Associados a Câncer , Neoplasias Colorretais , Humanos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/metabolismo , Masculino , Feminino , Biomarcadores Tumorais/análise , Fibroblastos Associados a Câncer/patologia , Fibroblastos Associados a Câncer/metabolismo , Idoso , Pessoa de Meia-Idade , Análise por Conglomerados , Imuno-Histoquímica , Microambiente Tumoral , Prognóstico , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/metabolismo , Células Estromais/patologia , Células Estromais/metabolismo , Decorina/análise , Decorina/metabolismo , Adulto , Idoso de 80 Anos ou mais , Estimativa de Kaplan-Meier
3.
Biochim Biophys Acta Mol Basis Dis ; 1870(6): 167275, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38844112

RESUMO

Albumin infusions improve circulatory and renal function in patients with decompensated cirrhosis. However, there is no convincing evidence that hypoalbuminemia contributes to ascites formation in liver cirrhosis. The aim of our study is to determine the exact role of hypoalbuminemia in the formation of ascites caused by liver cirrhosis and its underlying mechanism. Clinical profiles of patients with liver cirrhosis retrospectively analyzed. The details of albumin involved in ascites formation were investigated in rat model and murine model. Statistical analysis demonstrated hypoalbuminemia was an independent risk factor for ascites formation in patients with liver cirrhosis (OR = 0.722, P < 0.001). In carbon tetrachloride (CCl4)-induced rat model of liver cirrhosis, a significant reduction in serum albumin was observed in rats with ascites (13.37 g/L) compared with rats without ascites (21.43 g/L, P < 0.001). In thioacetamide (TAA)-treated mice, ascites amount of heterozygous albumin (Alb+/-) mice (112.0 mg) was larger than that of wild-type (Alb+/+) mice (58.46 mg, P < 0.001). In CCl4-induced chronic liver injury, ascites amounts of Alb+/- or Alb+/+ mice were 80.00 mg or 48.46 mg (P = 0.001). Further study demonstrated 24-h urinary sodium excretion in Alb+/- mice was lower than that of Alb+/+ mice in TAA/CCl4-induce murine models of liver cirrhosis. Additionally, serum sodium concentration of Alb+/- mice was lower than that of Alb+/+ mice. In cirrhotic mice, higher level of antidiuretic hormone was observed in Alb+/- mice compared with the control; and renal aquaporin (AQP2) expression in Alb+/- mice was significantly higher than that of WT mice. These revealed hypoalbuminemia contributed to the occurrence of ascites in liver cirrhosis through sodium and water retention.


Assuntos
Ascite , Hipoalbuminemia , Cirrose Hepática , Sódio , Animais , Hipoalbuminemia/metabolismo , Hipoalbuminemia/patologia , Ascite/metabolismo , Ascite/patologia , Sódio/metabolismo , Sódio/urina , Camundongos , Masculino , Humanos , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/complicações , Cirrose Hepática/genética , Feminino , Ratos , Tetracloreto de Carbono/toxicidade , Tetracloreto de Carbono/efeitos adversos , Pessoa de Meia-Idade , Aquaporina 2/metabolismo , Aquaporina 2/genética , Modelos Animais de Doenças , Estudos Retrospectivos , Albumina Sérica/metabolismo , Tioacetamida , Água/metabolismo , Idoso
4.
Micromachines (Basel) ; 15(4)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38675318

RESUMO

Arterial stiffness has been proved to be an important parameter in the evaluation of cardiovascular diseases, and Pulse Wave Velocity (PWV) is a strong indicator of arterial stiffness. Compared to regional PWV (PWV among different arteries), local PWV (PWV within a single artery) outstands in providing higher precision in indicating arterial properties, as regional PWVs are highly affected by multiple parameters, e.g., variations in blood vessel lengths due to individual differences, and multiple reflection effects on the pulse waveform. However, local PWV is less-developed due to its high dependency on the temporal resolution in synchronized signals with usually low signal-to-noise ratios. This paper presents a method for the noninvasive simultaneous measurement of two local PWVs in both left and right radial arteries based on the Fiber Bragg Grating (FBG) technique via correlation analysis of the pulse pairs at the fossa cubitalis and at the wrist. Based on the measurements of five male volunteers at the ages of 19 to 21 years old, the average left radial PWV ranged from 9.44 m/s to 12.35 m/s and the average right radial PWV ranged from 11.50 m/s to 14.83 m/s. What is worth mentioning is that a stable difference between the left and right radial PWVs was observed for each volunteer, ranging from 2.27 m/s to 3.04 m/s. This method enables the dynamic analysis of local PWVs and analysis of their features among different arteries, which will benefit the diagnosis of early-stage arterial stiffening and may bring more insights into the diagnosis of cardiovascular diseases.

5.
Int J Mol Sci ; 25(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38473788

RESUMO

Colorectal cancer (CRC) is one of the most common gastrointestinal cancers worldwide, with high morbidity and mortality rates. The evidence for the tumor-supporting capacities of cancer-associated fibroblasts (CAFs) that modulate cancer cell proliferation, invasion, metastasis, and tumor immunity, including in CRC, has been attracting attention. The present study examined the expression status of CD70 and POSTN in CRC and analyzed their association with clinicopathological features and clinical outcomes. In the present study, in total 15% (40/269) and 44% (119/269) of cases exhibited CD70 and POSTN expression on CAFs, respectively. Co-expression of CD70 and POSTN was detected in 8% (21/269) of patients. Fluorescent immunohistochemistry identified the co-expression of CD70 and POSTN with FAP and PDPN, respectively. ACTA2 was not co-expressed with CD70 or POSTN in CRC CAFs. CRC with CD70+/POSTN+ status in CAFs was significantly associated with distant organ metastasis (p = 0.0020) or incomplete resection status (p = 0.0011). CD70+/POSTN+ status tended to associate with advanced pT stage (p = 0.032) or peritoneal metastasis (p = 0.0059). Multivariate Cox hazards regression analysis identified CD70+/POSTN+ status in CAFs [hazard ratio (HR) = 3.78] as a potential independent risk factor. In vitro experiments revealed the activated phenotypes of colonic fibroblasts induced by CD70 and POSTN, while migration and invasion assays identified enhanced migration and invasion of CRC cells co-cultured with CD70- and POSTN-expressing colonic fibroblasts. On the basis of our observations, CD70 and POSTN immunohistochemistry can be used in the prognostication of CRC patients. CRC CAFs may be a promising target in the treatment of CRC patients.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Colorretais , Humanos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos/metabolismo , Imuno-Histoquímica , Proliferação de Células , Neoplasias Colorretais/patologia , Moléculas de Adesão Celular/metabolismo , Ligante CD27/metabolismo
6.
Int J Biol Macromol ; 264(Pt 1): 130581, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447828

RESUMO

Neutrophilic asthma is a persistent and severe inflammatory lung disease characterized by neutrophil activation and the mechanisms of which are not completely elucidated. Ubiquitin D (UBD) is a ubiquitin-like modifier participating in infections, immune responses, and tumorigenesis, while whether UBD involves in neutrophilic asthma needs further study. In this study, we initially found that UBD expression was significantly elevated and interleukin 17 (IL-17) signaling was enriched in the endobronchial biopsies of severe asthma along with neutrophils increasing by bioinformatics analysis. We further confirmed that UBD was upregulated in the lung tissues of neutrophilic asthma mouse model. UBD overexpression promoted IL-17 signaling activation. Knockdown of UBD suppressed the activation of IL-17 signaling. UBD interacted with TRAF2 and reduced the total and the K48-linked ubiquitination of TRAF2. However, IL-17 A stimulation increased both the total and the K48-linked ubiquitination of TRAF2. Together, these findings indicated that UBD was upregulated and played a critical role in IL-17 signaling which contributed to a better understanding of the complex mechanisms in neutrophilic asthma.


Assuntos
Asma , Interleucina-17 , Animais , Camundongos , Fator 2 Associado a Receptor de TNF/metabolismo , Asma/metabolismo , Pulmão/metabolismo , Neutrófilos/metabolismo , Ubiquitinas/metabolismo , Inflamação/patologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-38430605

RESUMO

Prolyl hydroxylase domain 2 (PHD2) is an important enzyme in the human body that perceives changes in oxygen concentration and regulates response in hypoxic environments. Evaluation of PHD2 inhibitory activity of natural products is crucial for drug development of hypoxia related diseases. At present, the detection of low concentration of α-ketoglutaric acid (the substrate of PHD2 enzymatic reaction) requires derivatization reactions or sample pretreatment, which undoubtedly increases the workload of PHD2 inhibitory activity evaluation. In this paper, a direct detection approach of α-ketoglutaric acid was established by using the online stacking strategy of capillary electrophoresis to evaluate the PHD2 inhibitory activity of natural products. Under optimized conditions, detection of a single sample can be achieved within 2 min. By calculation, the intraday precision RSD of the apparent electrophoretic mobility and peak areas of α-ketoglutaric acid are 0.92 % and 0.79 %, respectively, and the interday RSD were 1.27 % and 0.96 % respectively. The recoveries of the present approach were 97.9-105.2 %, and the LOQ and LOD were 2.0 µM and 5.0 µM, respectively. Furthermore, this approach was applied for the evaluation of inhibitory activity of PHD2 for 13 natural products, and PHD2 inhibitory activity of salvianolic acid A was firstly reported. The present work not only realizes evaluation of PHD2 inhibitory activity through direct detection of α-ketoglutaric acid, but also provides technical support for the discovery of potential drug molecules in hypoxia related diseases.


Assuntos
Produtos Biológicos , Eletroforese Capilar , Prolina Dioxigenases do Fator Induzível por Hipóxia , Ácidos Cetoglutáricos , Humanos , Produtos Biológicos/farmacologia , Eletroforese Capilar/métodos , Prolina Dioxigenases do Fator Induzível por Hipóxia/antagonistas & inibidores , Ácidos Cetoglutáricos/análise
8.
Pathobiology ; 91(5): 313-325, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527431

RESUMO

INTRODUCTION: Over the past decade, classifications using immune cell infiltration have been applied to many types of tumors; however, mesotheliomas have been less frequently evaluated. METHODS: In this study, 60 well-characterized pleural mesotheliomas (PMs) were evaluated immunohistochemically for the characteristics of immune cells within tumor microenvironment (TME) using 10 immunohistochemical markers: CD3, CD4, CD8, CD56, CD68, CD163, FOXP3, CD27, PD-1, and TIM-3. For further characterization of PMs, hierarchical clustering analyses using these 10 markers were performed. RESULTS: Among the immune cell markers, CD3 (p < 0.0001), CD4 (p = 0.0016), CD8 (p = 0.00094), CD163+ (p = 0.042), and FOXP3+ (p = 0.025) were significantly associated with an unfavorable clinical outcome. Immune checkpoint receptor expressions on tumor-infiltrating lymphocytes such as PD-1 (p = 0.050), CD27 (p = 0.014), and TIM-3 (p = 0.0098) were also associated with unfavorable survival. Hierarchical clustering analyses identified three groups showing specific characteristics and significant associations with patient survival (p = 0.016): the highest number of immune cells (ICHigh); the lowest number of immune cells, especially CD8+ and CD163+ cells (ICLow); and intermediate number of immune cells (ICInt). ICHigh tumors showed significantly higher expression of PD-L1 (p = 0.00038). Cox proportional hazard model identified ICHigh [hazard ratio (HR) = 2.90] and ICInt (HR = 2.97) as potential risk factors compared with ICLow. Tumor CD47 (HR = 2.36), tumor CD70 (HR = 3.04), and tumor PD-L1 (HR = 3.21) expressions were also identified as potential risk factors for PM patients. CONCLUSION: Our findings indicate immune checkpoint and/or immune cell-targeting therapies against CD70-CD27 and/or CD47-SIRPA axes may be applied for PM patients in combination with PD-L1-PD-1 targeting therapies in accordance with their tumor immune microenvironment characteristics.


Assuntos
Biomarcadores Tumorais , Linfócitos do Interstício Tumoral , Neoplasias Pleurais , Microambiente Tumoral , Humanos , Microambiente Tumoral/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Análise por Conglomerados , Neoplasias Pleurais/imunologia , Neoplasias Pleurais/patologia , Linfócitos do Interstício Tumoral/imunologia , Mesotelioma/imunologia , Mesotelioma/patologia , Adulto , Mesotelioma Maligno/imunologia , Mesotelioma Maligno/patologia , Idoso de 80 Anos ou mais , Prognóstico , Imuno-Histoquímica
9.
Liver Int ; 44(3): 691-705, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38082504

RESUMO

BACKGROUND AND AIM: Hepatotoxicity is a well-defined reaction to methotrexate (MTX), a drug commonly used for the treatment of rheumatoid arthritis and various tumours. We sought to elucidate the mechanism underlying MTX-induced hepatotoxicity and establish a potentially effective intervention strategy. METHODS: We administered MTX to liver cells and mice and assessed hepatotoxicity by cell viability assay and hepatic pathological changes. We determined ferroptosis and ferritinophagy by detecting ferroptosis-related markers and autophagic degradation of ferritin heavy chain 1 (FTH1). RESULTS: We have shown that hepatocytes treated with MTX undergo ferroptosis, and this process can be attenuated by ferroptosis inhibitors. Interestingly, NCOA4-mediated ferritinophagy was found to be involved in MTX-induced ferroptosis, which was demonstrated by the relief of ferroptosis through the inhibition of autophagy or knockdown of Ncoa4. Furthermore, MTX treatment resulted in the elevation of high-mobility group box 1 (HMGB1) expression. The depletion of Hmgb1 in hepatocytes considerably alleviated MTX-induced hepatotoxicity by limiting autophagy and the subsequent autophagy-dependent ferroptosis. It is noteworthy that glycyrrhizic acid (GA), a precise inhibitor of HMGB1, effectively suppressed autophagy, ferroptosis and hepatotoxicity caused by MTX. CONCLUSION: Our study shows the significant roles of autophagy-dependent ferroptosis and HMGB1 in MTX-induced hepatotoxicity. It emphasizes that the inhibition of ferritinophagy and HMGB1 may have potential as a therapeutic approach for preventing and treating MTX-induced liver injury.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Ferroptose , Proteína HMGB1 , Animais , Camundongos , Autofagia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Metotrexato/toxicidade , Metotrexato/uso terapêutico
10.
Pathol Int ; 74(1): 13-25, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38050808

RESUMO

The present study analyzed the expression of five independent immunohistochemical markers, CD4, CD8, CD66b, CD68, and CD163, on immune cells within the colorectal cancer (CRC) tumor microenvironment (TME). Using hierarchical clustering, patients were successfully classified according to significant associations with clinicopathological features and/or survival. Patients with mismatch repair-proficient (pMMR) CRC were categorized into four groups with survival differences (p = 0.0084): CD4Low , CD4High , MΦHigh , and CD8Low . MΦHigh tumors showed significantly higher expression of CD47 (p < 0.0001), a phagocytosis checkpoint molecule. These tumors contained significantly greater numbers of PD-1+ (p < 0.0001), TIM-3+ (p < 0.0001), and SIRPA+ (p < 0.0001) immune cells. Notably, 10% of the patients with pMMR CRC expressed PD-L1 (CD274) on tumor cells with significantly worse survival (p = 0.00064). The Cox proportional hazards model identified MΦ High (hazard ratio [HR] = 2.02, 95%, p = 0.032), CD8Low (HR = 2.45, p = 0.011), and tumor PD-L1 expression (HR = 2.74, p = 0.0061) as potential risk factors. PD-L1-PD-1 and/or CD47-SIRPA axes targeting immune checkpoint therapies might be considered for patients with pMMR CRC according to their tumor cells and tumor immune microenvironment characteristics.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/patologia , Antígeno CD47 , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Biomarcadores Tumorais/análise , Microambiente Tumoral
11.
Micromachines (Basel) ; 14(11)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38004881

RESUMO

Semiconductor chips on a substrate have a wide range of applications in electronic devices. However, environmental temperature changes may cause mechanical buckling of the chips, resulting in an urgent demand to develop analytical models to study this issue with high efficiency and accuracy such that safety designs can be sought. In this paper, the thermal buckling of chips on a substrate is considered as that of plates on a Winkler elastic foundation and is studied by the symplectic superposition method (SSM) within the symplectic space-based Hamiltonian system. The solution procedure starts by converting the original problem into two subproblems, which are solved by using the separation of variables and the symplectic eigenvector expansion. Through the equivalence between the original problem and the superposition of subproblems, the final analytical thermal buckling solutions are obtained. The SSM does not require any assumptions of solution forms, which is a distinctive advantage compared with traditional analytical methods. Comprehensive numerical results by the SSM for both buckling temperatures and mode shapes are presented and are well validated through comparison with those using the finite element method. With the solutions obtained, the effects of the moduli of elastic foundations and geometric parameters on critical buckling temperatures and buckling mode shapes are investigated.

12.
Pharmaceuticals (Basel) ; 16(8)2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37631068

RESUMO

Neuroinflammation is a common pathogenetic sign of depression and is closely linked to the development of depression. Many clinical anti-inflammatory drugs act as antidepressants by reducing the neuroinflammatory response. Previous research found that gypenosides and their bioactive compound gypenoside-14 (GP-14) had neuroprotective effects against hypoxia-induced injury and reduced neuroinflammation-related high-altitude cerebral edema. Here we investigated the effects of GP-14 on the lipopolysaccharide (LPS)-induced depression-like behavior model. LPS (0.5 mg/kg) was injected into mice intraperitoneally for 7 consecutive days to induce depression-like behavior, which is considered a model for the exacerbation of depression. GP-14 in the amount of 100 mg/kg was simultaneously administered by gavage for 7 days. In the LPS-induced depression model, GP-14 not only attenuated depression-like behavior but also improved the anxiety-like behavior of the mice. Additionally, GP-14 treatment mitigated learning and cognitive decline in depressed mice. ELISA and immunofluorescence staining results revealed that GP-14 inhibited the upregulation of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6), and suppressed the activation of astrocytes induced with LPS, indicating its potent anti-inflammatory effect. GP-14 pretreatment in C8 cells and primary astrocytes can inhibit the activation of the NF-κB signaling pathway and downregulate the levels of pro-inflammatory factors. In summary, our findings showed that GP-14 had significant anti-inflammation and anti-depression properties; thus, GP-14 could be a promising lead compound for treating depression.

13.
Microsyst Nanoeng ; 9: 96, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37484501

RESUMO

Spiking neural networks (SNNs) have immense potential due to their utilization of synaptic plasticity and ability to take advantage of temporal correlation and low power consumption. The leaky integration and firing (LIF) model and spike-timing-dependent plasticity (STDP) are the fundamental components of SNNs. Here, a neural device is first demonstrated by zeolitic imidazolate frameworks (ZIFs) as an essential part of the synaptic transistor to simulate SNNs. Significantly, three kinds of typical functions between neurons, the memory function achieved through the hippocampus, synaptic weight regulation and membrane potential triggered by ion migration, are effectively described through short-term memory/long-term memory (STM/LTM), long-term depression/long-term potentiation (LTD/LTP) and LIF, respectively. Furthermore, the update rule of iteration weight in the backpropagation based on the time interval between presynaptic and postsynaptic pulses is extracted and fitted from the STDP. In addition, the postsynaptic currents of the channel directly connect to the very large scale integration (VLSI) implementation of the LIF mode that can convert high-frequency information into spare pulses based on the threshold of membrane potential. The leaky integrator block, firing/detector block and frequency adaptation block instantaneously release the accumulated voltage to form pulses. Finally, we recode the steady-state visual evoked potentials (SSVEPs) belonging to the electroencephalogram (EEG) with filter characteristics of LIF. SNNs deeply fused by synaptic transistors are designed to recognize the 40 different frequencies of EEG and improve accuracy to 95.1%. This work represents an advanced contribution to brain-like chips and promotes the systematization and diversification of artificial intelligence.

14.
Med Phys ; 50(10): 5987-6007, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37345214

RESUMO

Oxygen-enhanced MR imaging (OE-MRI) is a special proton imaging technique that can be performed without modifying the scanner hardware. Many fundamental studies have been conducted following the initial reporting of this technique in 1996, illustrating the high potential for its clinical application. This review aims to summarise and analyse current pulse sequences and T1 measurement methods for OE-MRI, including fundamental theories, existing pulse sequences applied to OE-MRI acquisition and T1 mapping. Wash-in and wash-out time identify lung function and are sensitive to ventilation; thus, dynamic OE-MRI is also discussed in this review. We compare OE-MRI with the primary competitive technique, hyperpolarised gas MRI. Finally, an overview of lower-field applications of OE-MRI is highlighted, as relatively recent publications demonstrated positive results. Lower-field OE-MRI, which is lower than 1.5 T, could be an alternative modality for detecting lung diseases. This educational review is aimed at researchers who want a quick summary of the steps needed to perform pulmonary OE-MRI with a particular focus on sequence design, settings, and quantification methods.


Assuntos
Pneumopatias , Oxigênio , Humanos , Pulmão/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Respiração
15.
Materials (Basel) ; 16(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37176311

RESUMO

Rock masses are inherently heterogeneous, with numerous fractures that significantly affect their mechanical properties, fracture characteristics, and acoustic emission features due to the interactions between fractures or between fractures and the rock mass. Microbially induced calcite precipitation (MICP) technology, as an emerging non-destructive biological grouting reinforcement method, can repair fractured rock masses and alter their internal conditions. To investigate the mechanical properties, failure process evolution, and MICP repair effects of sandstone before and after repair, uniaxial compression tests were conducted on prefabricated, fractured (0.7-2.0 mm width) filled and unfilled rock samples, with acoustic emission monitoring throughout the process. Acoustic emission signal characteristics of the rock samples under stress were comparatively analyzed, determining the rock failure process and the microscopic failure types at compression-density stages, elastic stages, and destruction stages. The results show that the properties of the filled specimens improved, the failure process was mitigated, and the final failure stage was dominated by tension signals, accounting for over 60% of the total. The filling effect was better than 1.5-2.0 mm when the fracture width was 0.7-1.0 mm. The study deeply reveals the evolutionary process of compressive failure of the two types of rocks under different fracture widths, and by correlating the acoustic emission parameters with the stress-strain process, it provides a theoretical basis for repairing rock fractures using microbial engineering technology and offers experimental evidence and possible directions for the improvement and optimization of MICP technology.

16.
Phytochemistry ; 211: 113704, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37146703

RESUMO

Zanthoxylum armatum DC. is an important medicinal plant, and its pericarps are commonly used as a natural spice in Asian countries. In this study, fifteen alkylamides were isolated and elucidated from the pericarps of Z. armatum, including five undescribed alkylamides (1-5) and ten known compounds (6-15). The molecular structures of all compounds were elucidated by 1D and 2D NMR spectroscopic analysis and mass spectrometry, among which the absolute configuration of compound 15 was determined by the Mo2(OAc)4-induced circular dichroism method. Moreover, all compounds were screened for their neuroprotective activity against H2O2-induced oxidative stress in human neuroblastoma SH-SY5Y cells for the evaluation of their neuroprotective activity. Especially, compounds 2-4 expressed potential neuroprotective activity, and further research showed that the cell viability was significantly enhanced in a concentration dependent manner when the cells were treated for 6 h. Moreover, compounds 2-4 could decrease reactive oxygen species accumulation. This paper enriched structure types of alkylamides in Zanthoxylum armatum.


Assuntos
Neuroblastoma , Zanthoxylum , Humanos , Zanthoxylum/química , Peróxido de Hidrogênio/farmacologia , Espectrometria de Massas , Estrutura Molecular
17.
ACS Omega ; 8(15): 14197-14207, 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37091375

RESUMO

To study the dynamic evolution law of the oxidation heating process of coal spontaneous combustion in the goaf during the advancing process of the working face, a dynamic model of oxidation heating of coal spontaneous combustion in the goaf was established on the basis of deformed geometry. Through numerical simulation research, the evolution and migration laws of seepage field, oxygen concentration field, temperature field, and high-temperature area of coal spontaneous combustion in the goaf during the advancement of the working face was obtained. The results indicate that the distribution of the bulking coefficient, porosity, and permeability of the falling coal and rock mass in the goaf is nonuniform. They are relatively large in the area near the working face and the inlet and return airway and remain relatively unchanged with the advancement of the working face, but they are constantly decreasing in the location of the gob in the middle and deep. The oxygen concentration in the goaf presents an asymmetrical distribution. The oxygen concentration distribution area on the inlet side is wider than that on the return air side. At the same depth of the goaf, the oxygen concentration gradually decreases from the inlet side to the return air side; after the advancement distance exceeds 200 m, the air leakage in the goaf basically disappears, and the oxygen concentration decreases to zero. The high-temperature area of coal spontaneous combustion oxidation in the goaf was mainly concentrated on the air inlet side and extended toward the return air side. The advancing speed has a significant effect on the oxidation heating process of coal spontaneous combustion in the dynamic goaf. Under the same propulsion distance, when the advancing speed is 6 m/day, the highest temperature in the goaf is about 40 °C, and when the advancing speed is 2 m/day, the highest temperature in the goaf is as high as 120 °C. The smaller the advancing speed, the higher the heating rate of the goaf and the closer the high-temperature area to the working surface. The higher the advancing speed, the lower the temperature of the high-temperature point of the goaf and the greater the depth of the high-temperature point of the high temperature area; when the advancing speed is 2 m/day, the highest temperature point in the goaf is 70 m away from the working face, whereas when the advancing speed is 6 m/day, it reaches 174.6 m.

18.
Cancers (Basel) ; 15(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36765564

RESUMO

Evidence for the tumor-supporting capacities of cancer-associated fibroblasts (CAFs) has rapidly been accumulating. To uncover clinicopathological importance of periostin (POSTN) expression in colorectal cancer (CRC), the present study immunohistochemically examined its expression status. Furthermore, to reveal its mechanisms involved, molecular experiments were performed. In CRC tissues, 44% of the cases (119/269) exhibited POSTN expression in the CAFs. In contrast, CRC cells expressed POSTN at almost undetectable levels. Survival analyses identified that patients with POSTN-positive CRC had a significantly worse 5-year survival rate (63.2% vs. 81.2%; p = 0.011). Univariate analyses revealed that POSTN positivity was associated with peritoneal (p = 0.0031) and distant organ metastasis (p < 0.001). Furthermore, immunohistochemical analyses identified a significant association between POSTN and p53 complete loss status in CRC cells. Decorin and fibroblast activation protein expression in CAFs was also associated with POSTN. POSTN significantly enhanced the migration of both CRC cells and fibroblasts with FAK and AKT or STAT3 activation, and co-culture assays demonstrated the communication between CRC cells and fibroblasts, which enhanced STAT3 activation in fibroblasts. On the basis of our results, we speculated that stromal POSTN accelerated metastasis via stromal remodeling capacity and activated the migration of both tumor and stromal cells.

19.
Sensors (Basel) ; 22(23)2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36501871

RESUMO

The large view angle and complex background of UAV images bring many difficulties to the detection of small pedestrian targets in images, which are easy to be detected incorrectly or missed. In addition, the object detection models based on deep learning are usually complex and the high computational resource consumption limits the application scenarios. For small pedestrian detection in UAV images, this paper proposes an improved YOLOv5 method to improve the detection ability of pedestrians by introducing a new small object feature detection layer in the feature fusion layer, and experiments show that the improved method can improve the average precision by 4.4%, which effectively improves the pedestrian detection effect. To address the problem of high computational resource consumption, the model is compressed using channel pruning technology to reduce the consumption of video memory and computing power in the inference process. Experiments show that the model can be compressed to 11.2 MB and the GFLOPs of the model are reduced by 11.9% compared with that before compression under the condition of constant inference accuracy, which is significant for the deployment and application of the model.


Assuntos
Pedestres , Humanos , Tecnologia
20.
J Clin Lab Anal ; 36(12): e24787, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36441597

RESUMO

BACKGROUND: To examine the association between low-density lipoprotein cholesterol (LDL-C) concentrations and the risk of a large hematoma volume after intracerebral hemorrhage (ICH). METHODS: Patients from the Kailuan study (Tangshan, China) who were hospitalized with ICH during 2006 and 2020 were included in this study. The concentration of lipid concentrations, hematoma volume and other clinical characteristics were retrospectively collected and analyzed. Hematoma volumes were measured on the first available brain scan using the ABC/2 method. LDL-C concentrations were obtained from the last physical examination before the occurrence of ICH. LDL-C concentration was categorized into four groups in accordance with the quartiles. Logistic regression was used to assess the association between LDL-C concentrations and the risk of a large hematoma volume of ≥30 ml. A generalized linear regression model was used to analyze the dose-response relationship between LDL-C concentration and hematoma volume. RESULTS: A total of 836 patients with ICH were evaluated. In the Multivariate logistic regression, compared to the second quartile of LDL_C, the first quartile of LDL_C had a significantly higher risk of a large hematoma volume (OR 2.49 [95% CI 1.54-4.01]), and the higher quartile of LDL_C is not associated with higher odds of large hematoma volume. In the generalized linear regression model, the adjusted ß for the association between LDL-C concentration and hematoma volume was 9.46 (95% confidence interval 2.87-16.04), whereas higher LDL-C concentration was not associated with a large hematoma volume. CONCLUSIONS: This study confirmed that low LDL-C concentrations prior to ICH are associated with a higher risk of a large hematoma volume.


Assuntos
Hemorragia Cerebral , Hematoma , Humanos , LDL-Colesterol , Estudos Retrospectivos , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/complicações , Hematoma/etiologia , Hematoma/complicações , Neuroimagem
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