Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 68
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
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.
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
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.
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.

5.
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.

6.
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.

7.
Int J Med Sci ; 19(2): 377-392, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35165523

RESUMO

Background: Necroptosis, a cell death of caspase-independence, plays a pivotal role in cancer biological regulation. Although necroptosis is closely associated with oncogenesis, cancer metastasis, and immunity, there remains a lack of studies determining the role of necroptosis-related genes (NRGs) in the highly immunogenic cancer type, kidney renal clear cell carcinoma (KIRC). Methods: The information of clinicopathology and transcriptome was extracted from TCGA database. Following the division into the train and test cohorts, a three-NRGs (TLR3, FASLG, ZBP1) risk model was identified in train cohort by LASSO regression. The overall survival (OS) comparison was conducted between different risk groups through Kaplan-Meier analysis, which was further validated in test cohort. The Cox proportional hazards regression model was introduced to assess its impact of clinicopathological factors and risk score on survival. ESTIMATE and CIBERSORT algorithms were introduced to evaluate immune microenvironment, while enrichment analysis was conducted to explore the biological significance. Correlation analysis was applied for the correlation assessment between checkpoint gene expression and risk score, between gene expression and therapeutic response. Gene expressions from TCGA were verified by GEO datasets and immunohistochemistry (IHC) analysis. Results: This NRGs-related signature predicted poorer OS in high-risk group, which was also verified in test cohort. Risk score could also independently predict survival outcome of KIRC. Significant changes were also found in immune microenvironment and checkpoint gene expressions between different risk groups, with immune functional enrichment in high-risk group. Interestingly, therapeutic response was correlated with the expressions of NRGs. The expressions of NRGs from TCGA were consistent with those from GEO datasets and IHC analysis. Conclusion: The NRGs-related signature functions as a novel prognostic predictor of immune microenvironment and therapeutic response in KIRC.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Necroptose/genética , Transcriptoma/genética , Microambiente Tumoral/genética , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/mortalidade , Estudos de Coortes , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Análise de Regressão , Fatores de Risco
8.
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
9.
J Ultrasound Med ; 40(11): 2477-2486, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33470432

RESUMO

OBJECTIVES: To evaluate the value of time-intensity curve (TIC) analysis of contrast-enhanced ultrasound (CEUS) signal to differentiate malignant from benign orbital space-occupying lesions. METHODS: The CEUS signal of 111 patients with orbital space-occupying lesions was retrospectively analyzed using SonoLiver software. TIC-related parameters such as the arrival time (AT), rise time (RT), time to peak (TTP), maximum intensity (IMAX), mean transit time (mTT), slope of the increase (RS), and slope of the decrease (DS) were compared between the malignant and benign groups. Receiver operating characteristic (ROC) curve analysis was used to acquire the cutoff values of these parameters for differential diagnosis. RESULTS: TIC patterns were characterized by fast increase and fast decrease in signal intensity in the malignant group, fast increase and a slow decrease in signal intensity in the benign group. The differences in the IMAX, RS, DS, mTT, TTP, and RT between the 2 groups were statistically significant (p <.01), while the difference in the AT were not (p = .672). ROC curve analysis showed that IMAX = 427.20, DS = 34.72, and mTT = 33.55 were the best cutoff values for differential diagnosis of malignant and benign space-occupying lesions. The accuracy rate of CEUS visual evaluation for differential diagnosis was 66.67% (74/111), while TIC quantitative analysis could effectively improve the accuracy to 89.19% (99/111). CONCLUSIONS: TIC analysis can improve CEUS efficiency to differentiate malignant from benign orbital space-occupying lesions.


Assuntos
Meios de Contraste , Diagnóstico Diferencial , Humanos , Curva ROC , Estudos Retrospectivos , Ultrassonografia
10.
J Ultrasound Med ; 40(9): 1787-1794, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33174632

RESUMO

OBJECTIVES: Coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic, raising widespread public health concerns. Our team treated hospitalized patients with COVID-19 in Wuhan, where the outbreak first began, and we suspected that SARS-CoV-2 may cause testicular infection in male patients. We conducted this study to explore that observation. METHODS: We enrolled male patients with a confirmed diagnosis of COVID-19 and performed a bedside ultrasound (US) examination of the scrotum, focused on findings of acute inflammation such as tunica albuginea thickening, enlargement and heterogeneous echogenicity of the testis, epididymis, or both, an abscess, scrotal wall edema, and hydrocele. Then we compared the proportions of observed epididymo-orchitis in patients from different age groups and COVID-19 severity groups. RESULTS: A total of 142 patients with COVID-19 were enrolled in our study, and 32 (22.5%) patients had acute orchitis, epididymitis, or epididymo-orchitis on scrotal US imaging, according to the diagnosis criteria. The observed risk of acute scrotal infection increased with age, with the incidence reaching 53.3% in men older than 80 years. We also observed that men with severe COVID-19 had a significantly higher possibility of epididymo-orchitis compared to the nonsevere COVID-19 group (P = .037). CONCLUSIONS: This study shows US imaging evidence that SARS-CoV-2 may cause infection of the testis or epididymis, and the risk is worthy of the attention of clinicians.


Assuntos
COVID-19 , Orquite , Idoso de 80 Anos ou mais , China/epidemiologia , Humanos , Masculino , Orquite/diagnóstico por imagem , Orquite/epidemiologia , SARS-CoV-2 , Ultrassonografia
11.
Clin Invest Med ; 43(3): E44-48, 2020 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-32971584

RESUMO

PURPOSE: Pulmonary hypertension (PH) is a frequent and serious cardiovascular complication in patients with end-stage renal disease (ESRD) on dialysis. The purpose of this study was to investigate the prevalence of PH and its associated factors in patients with ESRD on maintenance dialysis and predialysis patients. METHODS: The medical records of ESRD patients who underwent kidney transplantation between January 2011 and December 2017 were retrospectively reviewed. Demographic and clinical characteristics including echocardiographic findings before joining the waiting list for transplantation were evaluated and compared among groups divided according to dialysis or not and dialysis types. The results of transthoracic Doppler echocardiography were used to determine the pulmonary artery pressure. Pulmonary hypertension was defined as a systolic pulmonary artery pressure (sPAP) greater than 35 mmHg. Univariate and multivariate analyses were used to investigate factors associated with PH. RESULTS: Data from 35 pre-dialysis patients with ESRD, 72 maintenance hemodialysis (HD) and 34 peritoneal dialysis (PD) patients were analysed. Pulmonary hypertension was 20.69% in pre-dialysis patients, 16.7% in HD patients and 14.7% in PD patients (P=0.957). There were negative correlations between sPAP and calcium (r=-0.230, P=0.012), Ca×P(r=-0.210, P=0.021), hemoglobin (r=-0.243, P=0.008) and a positive correlation between sPAP and cardiac output (r=0.481, P=0.000). Cardiac output (CO) was an independent risk factor of sPAP (B=1.431, confidence interval [CI] 95%: 0.687 to 2.175, P=0.000). CONCLUSION: Incidence of PH was not statistically different in ESRD patients on dialysis and pre-dialysis patients. Uremia may play a major role in the pathogenesis of PH in patients.


Assuntos
Hipertensão Pulmonar , Falência Renal Crônica , Diálise , Humanos , Hipertensão Pulmonar/etiologia , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Estudos Retrospectivos
12.
Int J Hyperthermia ; 36(1): 1129-1136, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31744350

RESUMO

Background: Tertiary hyperparathyroidism (THPT) is very common in hemodialysis patients with secondary hyperparathyroidism. However, a medical treatment is not indicated for THPT.Purpose: To investigate the feasibility, safety and efficacy of microwave ablation (MWA) in treating THPT.Materials and methods: Twenty-three patients with THPT were enrolled and treated with MWA. Clinical characteristics, serum levels of intact parathyroid hormone (iPTH), calcium, phosphorus and alkaline phosphatase (ALP), as well as treatment outcomes, were evaluated pre- and post-MWA. All patients were followed for >36 months for all assessable clinical data.Results: All patients successfully completed MWA. The mean follow-up was 47.0 ± 8.4 months. Immediately 1-day post-MWA, iPTH, calcium, phosphorus and ALP levels significantly decreased (all p < 0.001). During the long-term follow-up, iPTH levels increased gradually until 24 months and then remained at stable levels. After MWA, serum calcium reached stable levels at 24 months, while phosphorus and ALP reached stable levels at 6 months, and the levels were in the normal range or slightly higher than the upper normal limit. No obvious blood flow signals or significant recurrence was observed in the surgical nodules during follow-up. In the last follow-up, all nodules were persistent, but their maximum diameter and average volume were significantly lower after MWA (both p < 0.001), with an average reduction of 75.9 ± 11.3%. All patients had no major complications during MWA and follow-up.Conclusions: MWA is feasible, safe, effective and minimally invasive in treating THPT. Thus, MWA can be a nonsurgical alternative for treating THPT patients who are ineligible for surgery.


Assuntos
Técnicas de Ablação/métodos , Hiperparatireoidismo/diagnóstico por imagem , Adulto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Retrospectivos
13.
BMC Endocr Disord ; 18(1): 49, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-30053902

RESUMO

BACKGROUND: Glycaemic control is one of the most effective strategies for the treatment of diabetes-related erectile dysfunction (DMED). Compared to conventional anti-diabetic drugs and insulin, islet transplantation is more effective in the treatment of diabetic complications. The aim of this study was to investigate the efficacy of islet transplantation for reversing advanced-stage DMED in rats and to observe its influence on corpus cavernosum fibrosis. METHODS: Wistar rats were intraperitoneally injected with streptozotocin to establish a diabetes model. After 12 weeks, the rats were divided into 4 groups: diabetic, insulin, islet transplantation, and normal control. Following supplementation, the changes in blood glucose and weight were determined sequentially. Penile erectile function was evaluated by apomorphine experiments in the fourth week, and the penile corpus cavernosum was also collected for assessment by Masson staining, immunohistochemistry and Western blot to observe the spongy tissue and the related cellular changes at the molecular level. RESULTS: Islet transplantation significantly ameliorated penile erectile function in advanced-stage diabetic rats. The ratio of corpus cavernosum smooth muscle cells to fibroblasts and the expression level of α-SMA in the islet transplantation group were significantly higher than those in the diabetic and insulin groups. In addition, the expression levels of TGF-ß1, p-Samd2, and connective tissue growth factor (CTGF) in the islet transplantation and insulin groups were much lower than those in the diabetic group, while those in the islet transplantation group were significantly lower than those in the insulin group. CONCLUSIONS: Our findings strongly suggest that islet transplantation can promote the regeneration of smooth muscle cells and ameliorate corpus cavernosum fibrosis to restore its normal structure in advanced-stage diabetic rats. The possible mechanism of ameliorating corpus cavernosum fibrosis by islet transplantation may be associated with improvement of the hyperglycaemic status in diabetic rats, thereby inhibiting the TGF-ß1/Samd2/CTGF pathway.


Assuntos
Diabetes Mellitus Experimental/terapia , Diabetes Mellitus Tipo 1/terapia , Transplante das Ilhotas Pancreáticas , Doenças do Pênis/terapia , Pênis/patologia , Animais , Complicações do Diabetes/terapia , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/complicações , Disfunção Erétil/etiologia , Disfunção Erétil/terapia , Fibrose/etiologia , Fibrose/terapia , Masculino , Doenças do Pênis/etiologia , Ratos , Ratos Wistar , Estreptozocina
14.
J Sci Food Agric ; 98(15): 5683-5689, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29736983

RESUMO

BACKGROUND: Soy protein isolate (SPI) has promising applications in various food products because of its excellent functional properties and nutritional quality. The structural and emulsifying properties of covalently modified SPI by (-)-epigallocatechin-3-gallate (EGCG) were investigated. RESULTS: SPI was covalently modified by EGCG under alkaline conditions. SDS-PAGE analysis revealed that EGCG modification caused crosslinking of SPI proteins. Circular dichroism spectra demonstrated that the secondary structure of SPI proteins was changed by EGCG modification. In addition, the modifications resulted in the perturbation of the tertiary structure of SPI as evidenced by intrinsic fluorescence spectra and surface hydrophobicity measurements. Oil-in-water emulsions of modified SPI had smaller droplet sizes and better creaming stability compared to those from unmodified SPI. CONCLUSION: The covalent modification by EGCG improved the emulsifying property of SPI. This study therefore provided an innovative approach for improving the emulsifying properties of proteins. © 2018 Society of Chemical Industry.


Assuntos
Proteínas de Soja/química , Catequina/análogos & derivados , Catequina/química , Dicroísmo Circular , Emulsões/química , Interações Hidrofóbicas e Hidrofílicas , Conformação Proteica em alfa-Hélice , Proteínas de Soja/isolamento & purificação
15.
Tumour Biol ; 37(7): 9343-55, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26779633

RESUMO

The prognosis of hepatocellular carcinoma (HCC) after surgical resection remains unsatisfactory for the majority of HCC patients who developed early recurrence or metastasis. There is still a lack of reliable biomarkers that can be used to predict the possibility of recurrence/metastasis in HCC patients after operation. In the current study, annexin A4, a calcium-dependent phospholipid-binding protein, has been found to be significantly elevated in HCC patients with early recurrence/metastasis, and had a strong correlation with portal vein tumor thrombosis (p = 0.03) and advanced BCLC stage (p = 0.002). Cox proportional hazards regression analysis revealed that annexin A4 was an independent prognostic predictor for both early recurrence/metastasis (HR = 1.519, p = 0.032) and overall survival (HR = 1.827, p = 0.009) after surgical resection. Meanwhile, Kaplan-Meier analysis showed that Patients with high-expression levels of annexin A4 had higher recurrence rate and shorter overall survival than those with low expression (log-rank test, p < 0.001). Furthermore, in vitro studies have demonstrated that overexpression of annexin A4 facilitated HCC cell migration and invasion via regulating epithelial-mesenchymal transition (EMT). In conclusion, annexin A4 has played important roles in the progression of HCC, and might act as a potential prognostic biomarker for HCC.


Assuntos
Anexina A4/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/secundário , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/patologia , Anexina A4/genética , Apoptose , Biomarcadores Tumorais/genética , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Células Tumorais Cultivadas
16.
Pharmazie ; 71(12): 733-737, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442004

RESUMO

Rapamycin (Rap), a specific inhibitor of the mTOR signaling, has been shown to affect lipid metabolism in vitro and in vivo. Sirt-1, an NAD+ dependent deacetylase, regulates a variety of cellular processes, including aging, lifespan extension and glucose and lipid metabolism. Herein, we applied a cellular steatosis model to investigate whether rapamycin's role in lipid metabolism is sirt 1-associated. Cells were exposed to palmitate stimulation for 48 h with or without rapamycin treatment. Lipid droplets in AML12 cells were observed by oil red O staining, and the intracellular lipid content was measured. We found that rapamycin treatment, at a relatively low concentration, significantly attenuated lipid aggregation, whereas knockdown of sirt-1 by siRNA abrogated rapamycin's effect on ameliorating lipid accumulation. Moreover, rapamycin exposure increased the expression levels of sirt-1 and AMPK, and enhanced sirt-1 deacetylase activity in steatotic AML12 hepatocytes. This is the first report demonstrating that rapamycin ameliorates lipid accumulation through upregulating sirt-1 signaling supporting the hypothesis that rapamycin may positively influence sirt-1 signaling in maintaining metabolic homeostasis.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Palmitatos/antagonistas & inibidores , Sirolimo/farmacologia , Sirtuína 1/efeitos dos fármacos , Animais , Linhagem Celular , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/biossíntese , Palmitatos/farmacologia , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
17.
Pharmazie ; 70(9): 604-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26492646

RESUMO

Rapamycin, a classical inhibitor of the mammalian target of rapamycin (mTOR), has been intensively studied for its role in metabolism and verified to induce metabolic defects through mTORC2/Akt pathway. However, disparity of the results exists depending on the differences of the animal models or the detailed procedures. Moreover, data regarding the effect of rapamycin treatment in diabetic models are sparse. Therefore, we investigated its influence on glucose and lipid metabolism, and further analyzed its effect on the mTORC2/Akt pathway in a high-fat diet- and streptozotocin-induced diabetic mice model. Three-weeks old C57BL/6J mice were fed with a high fat diet (60 kcal% fat) and intraperitoneally injected with streptozotocin (100 mg/kg) at 6 weeks of age. Rapamycin (2 mg/kg) was orally given to the mice daily for consecutive 6 weeks. Body weight, blood lipid parameters and HbA(1c)% values were evaluated. Oral glucose test and insulin tolerance test were performed. Furthermore, western blot assay was applied to investigate the protein epression levels of Akt and PKCα, two key targets of the mTORC2/Akt pathway. Rapamycin-treated diabetic mice demonstrated less weight gain, more profound symptoms of polydipsia, polyphagia and polyuria, significant liver fat accumulation and exacerbated metabolic disorders including insulin resistance, hyperglycemia and dyslipidemia. Contrary to what have been expected, though significantly inhibiting mTORC1/S6K1 signaling, chronic rapamycin treatment failed to down-regulate mTORC2/Akt pathway. Our findings provide evidence that chronic rapamycin treatment may exacerbate metabolism in diabetic subjects and does not down-regulate mTORC2/Akt signialing in a high-fat diet- and streptozotocin-induced diabetic mice model.


Assuntos
Antibacterianos/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Dieta Hiperlipídica , Complexos Multiproteicos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Ingestão de Líquidos , Ingestão de Alimentos/efeitos dos fármacos , Teste de Tolerância a Glucose , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/patologia , Masculino , Alvo Mecanístico do Complexo 2 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacos
18.
Zhongguo Zhong Yao Za Zhi ; 39(22): 4288-92, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25850254

RESUMO

Endophytic fungi were isolated from Macleaya cordata growing in Dabie Mountain by agar-block method, and then the endophytic fungi were grouped into different types based on their morphological characteristics, and thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) were employed to determine whether the metabolic substances contained sanguinarine or not, and then preliminarily identified by morphological method. The results showed that the leaves hosted the largest number of endophytes (96 isolates) followed by the stems (57 isolates) and finally the roots (28 isolates), respectively. Based on morphological characteristics the endophytic fungi were grouped into 26 types in our study. TLC and HPLC results showed that there was sanguinarine in the metabolic substances of BLH 51 strain. According to the morphological characteristic, the BLH 51 strain was identified as Fusarium proliferatum. All these indicated that the medicinal plant M. cordata harbors abundant endophytes, which could be a new source for the search of active secondary metabolites.


Assuntos
Benzofenantridinas/metabolismo , Endófitos/isolamento & purificação , Fungos/isolamento & purificação , Isoquinolinas/metabolismo , Papaveraceae/microbiologia , Papaveraceae/metabolismo , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia , Caules de Planta/microbiologia
19.
Front Nutr ; 11: 1416910, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39036495

RESUMO

With the advancement of medical care and the continuous improvement of organ support technologies, some critically ill patients survive the acute phase of their illness but still experience persistent organ dysfunction, necessitating long-term reliance on intensive care and organ support, known as chronic critical illness. Chronic critical illness is characterized by prolonged hospital stays, high mortality rates, and significant resource consumption. Patients with chronic critical illness often suffer from malnutrition, compromised immune function, and poor baseline health, which, combined with factors like shock or trauma, can lead to intestinal mucosal damage. Therefore, effective nutritional intervention for patients with chronic critical illness remains a key research focus. Nutritional therapy has emerged as one of the essential components of the overall treatment strategy for chronic critical illness. This paper aims to provide a comprehensive review of the latest research progress in nutritional support therapy for patients with chronic critical illness.

20.
Transplant Proc ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39013746

RESUMO

BACKGROUND: The most common method of inducing brain death in rats is inflating an intracranially placed balloon of a Fogarty catheter inserted through a burr hole. However, because of the poor controllability of balloon position, the standardization and stability of the model are compromised. This study examined an improved technique in which the balloon is placed and fixed through double holes. METHODS: Forty adult male Sprague-Dawley (SD) rats were randomly and equally assigned into the single-hole (SH) group and the double-hole (DH) group. In each rat in the DH group, 2 holes were made, at the left frontal bone and parietal bone. A Fogarty catheter was inserted outside of the dura mater through the frontal hole, and its tip was guided out through the parietal hole using an arc-shaped needle. The SH group served as a control. In both groups, normal saline was injected into the balloon at 40 µL/minute until breathing stopped. Mechanical ventilation was instituted immediately and provided for another 6 hours after the determination of brain death. RESULTS: Typical blood pressure patterns were observed in both groups during the brain death induction period, whereas the fluctuation seemed relatively mild in the DH group. Stable brain death with normotension for 6 hours was induced successfully in 18 rats (90%) in the DH group and in 9 rats (45%) in the SH group (P = .002). The mean arterial pressure at 3 hours and thereafter was significantly higher in the DH group compared to the SH group (P < .05). CONCLUSIONS: Our results demonstrate that the DH method is a simple and effective technique to make the brain death model more stable and standardized, possibly due to precise control of the direction of the cannulation and the position of the balloon.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA