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1.
Cancers (Basel) ; 16(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39001509

RESUMO

Lung cancer, the leading cause of cancer-related incidence and mortality worldwide, is characterised by high invasiveness and poor prognosis. Novel therapeutic targets are required, especially for patients with inoperable metastatic disease requiring systemic therapies to improve patients' welfare. Recently, studies indicated that TMEM176B is a positive regulator in breast and gastric cancers, and it could be a potential target for treatment. In this study, we used single-cell sequencing, proteomics, Co-IP, and in vivo and in vitro experimental models to investigate the role of TMEM176B in lung adenocarcinoma development. Our study indicated that TMEM176B expression was enhanced in lung adenocarcinoma tissues, and it was associated with shorter overall survival (OS). TMEM176B promoted cellular functions, including cell proliferation, invasion, migration and adhesion in vitro and tumour growth in vivo. Moreover, the tube formation ability of endothelial cells was enhanced by treating with the tumour cell-conditioned medium. We have also demonstrated that TMEM176B regulated EMT via the FGFR1/JNK/Vimentin/Snail signalling cascade. Overall, our study suggests TMEM176B could be a potential therapeutic target in lung adenocarcinoma.

2.
Ann Lab Med ; 44(4): 343-353, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38433572

RESUMO

Background: Genetic defects in the human thyroid-stimulating hormone (TSH) receptor (TSHR) gene can cause congenital hypothyroidism (CH). However, the biological functions and comprehensive genotype-phenotype relationships for most TSHR variants associated with CH remain unexplored. We aimed to identify TSHR variants in Chinese patients with CH, analyze the functions of the variants, and explore the relationships between TSHR genotypes and clinical phenotypes. Methods: In total, 367 patients with CH were recruited for TSHR variant screening using whole-exome sequencing. The effects of the variants were evaluated by in-silico programs such as SIFT and polyphen2. Furthermore, these variants were transfected into 293T cells to detect their Gs/cyclic AMP and Gq/11 signaling activity. Results: Among the 367 patients with CH, 17 TSHR variants, including three novel variants, were identified in 45 patients, and 18 patients carried biallelic TSHR variants. In vitro experiments showed that 10 variants were associated with Gs/cyclic AMP and Gq/11 signaling pathway impairment to varying degrees. Patients with TSHR biallelic variants had lower serum TSH levels and higher free triiodothyronine and thyroxine levels at diagnosis than those with DUOX2 biallelic variants. Conclusions: We found a high frequency of TSHR variants in Chinese patients with CH (12.3%), and 4.9% of cases were caused by TSHR biallelic variants. Ten variants were identified as loss-of-function variants. The data suggest that the clinical phenotype of CH patients caused by TSHR biallelic variants is relatively mild. Our study expands the TSHR variant spectrum and provides further evidence for the elucidation of the genetic etiology of CH.


Assuntos
Hipotireoidismo Congênito , Humanos , China , Hipotireoidismo Congênito/diagnóstico , Hipotireoidismo Congênito/genética , AMP Cíclico , Oxidases Duais/genética , Mutação , Fenótipo , Receptores da Tireotropina/genética , Tireotropina
3.
Nat Commun ; 15(1): 2386, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493205

RESUMO

Charge density waves (CDWs) involved with electronic and phononic subsystems simultaneously are a common quantum state in solid-state physics, especially in low-dimensional materials. However, CDW phase dynamics in various dimensions are yet to be studied, and their phase transition mechanism is currently moot. Here we show that using the distinct temperature evolution of orientation-dependent ultrafast electron and phonon dynamics, different dimensional CDW phases are verified in CuTe. When the temperature decreases, the shrinking of c-axis length accompanied with the appearance of interchain and interlayer interactions causes the quantum fluctuations (QF) of the CDW phase until 220 K. At T < 220 K, the CDWs on the different ab-planes are finally locked with each other in anti-phase to form a CDW phase along the c-axis. This study shows the dimension evolution of CDW phases in one CDW system and their stabilized mechanisms in different temperature regimes.

4.
Neurospine ; 21(1): 273-285, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38317559

RESUMO

OBJECTIVE: This study aimed to evaluate the effects of 2 endoscopic spine surgeries on the biomechanical properties of normal and osteoporotic spines. METHODS: Based on computed tomography images of a healthy adult volunteer, 6 finite element models were created. After validating the normal intact model, a concentrated force of 400 N and a moment of 7.5 Nm were exerted on the upper surface of L3 to simulate 6 physiological activities of the spine. Five types of indices were used to assess the biomechanical properties of the 6 models, range of motion (ROM), maximum displacement value, intervertebral disc stress, maximum stress value, and articular protrusion stress, and by combining them with finite element stress cloud. RESULTS: In normal and osteoporotic spines, there was no meaningful change in ROM or disc stress in the 2 surgical models for the 6 motion states. Model N1 (osteoporotic percutaneous transforaminal endoscopic discectomy model) showed a decrease in maximum displacement value of 20.28% in right lateral bending. Model M2 (unilateral biportal endoscopic model) increased maximum displacement values of 16.88% and 17.82% during left and right lateral bending, respectively. The maximum stress value of L4-5 increased by 11.72% for model M2 during left rotation. In addition, using the same surgical approach, ROM, maximum displacement values, disc stress, and maximum stress values were more significant in the osteoporotic model than in the normal model. CONCLUSION: In both normal and osteoporotic spines, both surgical approaches were less disruptive to the physiologic structure of the spine. Furthermore, using the same endoscopic spine surgery, normal spine biomechanical properties are superior to osteoporotic spines.

6.
Nano Lett ; 24(1): 67-73, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38149785

RESUMO

Two-dimensional transition metal nitrides offer intriguing possibilities for achieving novel electronic and mechanical functionality owing to their distinctive and tunable bonding characteristics compared to other 2D materials. We demonstrate here the enabling effects of strong bonding on the morphology and functionality of 2D tungsten nitrides. The employed bottom-up synthesis experienced a unique substrate stabilization effect beyond van-der-Waals epitaxy that favored W5N6 over lower metal nitrides. Comprehensive structural and electronic characterization reveals that monolayer W5N6 can be synthesized at large scale and shows semimetallic behavior with an intriguing indirect band structure. Moreover, the material exhibits exceptional resilience against mechanical damage and chemical reactions. Leveraging these electronic properties and robustness, we demonstrate the application of W5N6 as atomic-scale dry etch stops that allow the integration of high-performance 2D materials contacts. These findings highlight the potential of 2D transition metal nitrides for realizing advanced electronic devices and functional interfaces.

7.
Nat Commun ; 14(1): 8082, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38057310

RESUMO

The pathogenesis of thyroid dysgenesis (TD) is not well understood. Here, using a combination of single-cell RNA and spatial transcriptome sequencing, we identify a subgroup of NF-κB-activated thyrocytes located at the center of thyroid tissues in postnatal mice, which maintained a partially mesenchymal phenotype. These cells actively protruded out of the thyroid primordium and generated new follicles in zebrafish embryos through continuous tracing. Suppressing NF-κB signaling affected thyrocyte migration and follicle formation, leading to a TD-like phenotype in both mice and zebrafish. Interestingly, during thyroid folliculogenesis, myeloid cells played a crucial role in promoting thyrocyte migration by maintaining close contact and secreting TNF-α. We found that cebpa mutant zebrafish, in which all myeloid cells were depleted, exhibited thyrocyte migration defects. Taken together, our results suggest that myeloid-derived TNF-α-induced NF-κB activation plays a critical role in promoting the migration of vertebrate thyrocytes for follicle generation.


Assuntos
NF-kappa B , Células Epiteliais da Tireoide , Animais , Camundongos , Células Mieloides , Fator de Necrose Tumoral alfa , Peixe-Zebra
9.
Horm Res Paediatr ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37703865

RESUMO

INTRODUCTION: Congenital hypothyroidism (CH), the most common neonatal endocrine disorder world-wide, can be caused by variants in the thyroid peroxidase (TPO) gene. This study aimed to identify TPO variants in Chinese patients with CH, analyze their impact on TPO function, and establish relationships between TPO genotypes and clinical characteristics. METHODS: A total of 328 patients with CH were screened for TPO variants by performing whole exome sequencing. The function of the detected TPO variants was investigated via transfection assays in vitro. The pathogenic effect of five novel variants was further assessed in silico. RESULTS: Among 328 patients with CH, 19 TPO variants, including six novel ones, were identified in 43 patients. Eighteen patients (5.5%) carried biallelic TPO variants. In vitro experiments showed that TPO activity was impaired to varying degrees in 17 variants. Furthermore, we determined that a residual TPO enzyme activity threshold of 15% may serve as a criterion for differentiating CH severity. CONCLUSIONS: According to our study, the prevalence of TPO variants among Chinese patients with CH was 13.1 %. Five novel variants led to impaired TPO function by altering its structure or by affecting its expression or cellular localization, which should result in impaired thyroid hormone synthesis.

10.
Front Endocrinol (Lausanne) ; 14: 1204678, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600710

RESUMO

Introduction: In recent years, the potential toxicities of different pharmaceuticals toward the thyroid system have received increasing attention. In this study, we aim to evaluate the toxic effects of pazopanib and axitinib, two anti-tumor drugs with widespread clinical use, on thyroid function in the zebrafish model. Methods: We measured levels of thyroid-related hormones using the commercial Enzyme-Linked Immunosorbent Assay (ELISA) kit. Whole-mount in situ hybridization (WISH) analysis was employed to detect target gene expression changes. Morphology of the thyroid were evaluated by using transgenic Tg (tg: EGFP) fish line under a confocal microscope. The relative mRNA expression of key genes was verified through quantitative real-time polymerase chain reaction (RT‒qPCR). The size and number of the follicles was quantified whereby Hematoxylin-Eosin (H & E) staining under a light microscope. Results: The results revealed that fertilized zebrafish embryos were incubated in pazopanib or axitinib for 96 hours, development and survival were significantly affected, which was accompanied by significant disturbances in thyroid endocrine system (e.g., increased thyroid-stimulating hormone (TSH) content and decreased triiodothyronine (T3) and thyroxine (T4) content, as well as transcription changes of genes associated with the hypothalamus-pituitary-thyroid (HPT) axis. Moreover, based on whole-mount in situ hybridization staining of tg and histopathological examination of zebrafish embryos treated with pazopanib and axitinib, we observed a significantly abnormal development of thyroid follicles in the Tg (tg: EGFP) zebrafish transgenic line. Conclusion: Collectively, these findings indicate that pazopanib and axitinib may have toxic effects on thyroid development and function, at least partially, by influencing the regulation of the HPT axis. Thus, we believe that the potential thyroid toxicities of pazopanib and axitinib in their clinical applications should receive greater attention.


Assuntos
Antineoplásicos , Peixe-Zebra , Animais , Axitinibe , Glândula Tireoide , Larva , Animais Geneticamente Modificados
11.
Rev Sci Instrum ; 94(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37212646

RESUMO

Time-resolved angle-resolved photoemission spectroscopy (Tr-APRES) gives direct insight into electron dynamics by providing temporal-, energy-, and momentum-resolved information in one experiment. A major obstacle to using high harmonic generation (HHG) probe pulses for photoemission spectroscopy is the low conversion efficiency, that is, the low flux of probe photons. We use a Yb-KGW based duo-laser source with an oscillator to pump two separate amplifiers and generate two synchronized pulsed laser sources with average energies of 7.5 and 6 W. By using the multiplate continuum method and chirped mirrors, the resulting flux of HHG photons at 33-70 eV can be increased 50-fold (up to 1011 photons/s) by using post-compressed 30 fs pulses compared with the photon flux generated by the fundamental 190 fs pulses. Moreover, pulses from the 6 W amplifier are used to pump an optical parametric amplifier that can vary the wavelengths for photoexcitation. The system performance is demonstrated by applying Tr-ARPES to single-crystal graphite. The front tilt broadening is significantly suppressed by the off-plane mounted conical grating, leading to a 184 fs temporal resolution that is mainly limited by the pump pulse. The energy resolution is 176 meV.

12.
Front Pharmacol ; 14: 1122890, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937842

RESUMO

Background: Cancer, also known as a malignant tumor, is caused by the activation of oncogenes, which leads to the uncontrolled proliferation of cells that results in swelling. According to the World Health Organization (WHO), cancer is one of the main causes of death worldwide. The main variables limiting the efficacy of anti-tumor treatments are side effects and drug resistance. The search for natural, safe, low toxicity, and efficient chemical compounds in tumor research is essential. Berberine is a pentacyclic isoquinoline quaternary ammonium alkaloid isolated from Berberis and Coptis that has long been used in clinical settings. Studies in recent years have reported the use of berberine in cancer treatment. In this study, we performed a bibliometric analysis of berberine- and tumor-related research. Materials and methods: Relevant articles from January 1, 2002, to December 31, 2021, were identified from the Web of Science Core Collection (WOSCC) of Clarivate Analytics. Microsoft Excel, CiteSpace, VOSviewer, and an online platform were used for the literary metrology analysis. Results: A total of 1368 publications had unique characteristics. Publications from China were the most common (783 articles), and Y. B. Feng (from China) was the most productive author, with the highest total citations. China Medical University (Taiwan) and Sun Yat-sen University (China) were the two organizations with the largest numbers of publications (36 each). Frontiers in Pharmacology was the most commonly occurring journal (29 articles). The present body of research is focused on the mechanism, molecular docking, and oxidative stress of berberine in tumors. Conclusion: Research on berberine and tumors was thoroughly reviewed using knowledge map and bibliometric methods. The results of this study reveal the dynamic evolution of berberine and tumor research and provide a basis for strategic planning in cancer research.

13.
J Med Genet ; 60(9): 874-884, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36898841

RESUMO

BACKGROUND: In several countries, thyroid dyshormonogenesis is more common than thyroid dysgenesis in patients with congenital hypothyroidism (CH). However, known pathogenic genes are limited to those directly involved in hormone biosynthesis. The aetiology and pathogenesis of thyroid dyshormonogenesis remain unknown in many patients. METHODS: To identify additional candidate pathogenetic genes, we performed next-generation sequencing in 538 patients with CH and then confirmed the functions of the identified genes in vitro using HEK293T and Nthy-ori 3.1 cells, and in vivo using zebrafish and mouse model organisms. RESULTS: We identified one pathogenic MAML2 variant and two pathogenic MAMLD1 variants that downregulated canonical Notch signalling in three patients with CH. Zebrafish and mice treated with N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butylester, a γ-secretase inhibitor exhibited clinical manifestations of hypothyroidism and thyroid dyshormonogenesis. Through organoid culture of primary mouse thyroid cells and transcriptome sequencing, we demonstrated that Notch signalling within thyroid cells directly affects thyroid hormone biosynthesis rather than follicular formation. Additionally, these three variants blocked the expression of genes associated with thyroid hormone biosynthesis, which was restored by HES1 expression. The MAML2 variant exerted a dominant-negative effect on both the canonical pathway and thyroid hormone biosynthesis. MAMLD1 also regulated hormone biosynthesis through the expression of HES3, the target gene of the non-canonical pathway. CONCLUSIONS: This study identified three mastermind-like family gene variants in CH and revealed that both canonical and non-canonical Notch signalling affected thyroid hormone biosynthesis.


Assuntos
Hipotireoidismo Congênito , Animais , Humanos , Camundongos , Hipotireoidismo Congênito/genética , Proteínas de Ligação a DNA/genética , Células HEK293 , Mutação , Proteínas Nucleares/genética , Hormônios Tireóideos/genética , Transativadores/genética , Fatores de Transcrição/genética , Peixe-Zebra
14.
Jt Dis Relat Surg ; 34(1): 50-57, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700263

RESUMO

OBJECTIVES: This study aims to compare the effectiveness and safety of intra-articular hyaluronic acid (HA) injections of ArtiAid®-Mini (AAM) and Ostenil®-Mini (OM) for the treatment of trapeziometacarpal joint osteoarthritis. PATIENTS AND METHODS: Between February 2018 and April 2020, this 24-week, double-blind, prospective, randomized, non-inferiority trial included a total of 17 patients (8 males, 9 females; mean age: 60.3±9.5 years; range, 42 to 76 years) who were treated with either intra-articular AAM (n=8) or OM (n=9). The primary outcome was pain according to a change in Visual Analog Scale (VAS) at 12 weeks after the last injection. The secondary outcomes included the change of VAS at Weeks 2, 4, and 24 after the injection, satisfaction, range of motion (ROM) of trapeziometacarpal joint, pinch strength, grip strength, and adverse events at Weeks 2, 4, 12, and 24 after the injection. RESULTS: Eight patients with AAM and eight patients with OM completed the follow-up. No significant differences in primary and secondary outcomes were observed between the two groups at baseline and each time point (p>0.05). The intra-group differences were significant in each time point. CONCLUSION: The intra-articular injection of either AAM or OM is effective and safe for patients with trapeziometacarpal osteoarthritis up to 24 weeks.


Assuntos
Osteoartrite do Joelho , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Resultado do Tratamento , Ácido Hialurônico , Injeções Intra-Articulares
15.
Graefes Arch Clin Exp Ophthalmol ; 261(5): 1473-1481, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36484805

RESUMO

PURPOSE: We aimed to investigate misalignment (tilt and decentration) and rotational stability of the implantable collamer lens V4c 6 months after implantation and to explore the potential risk factors associated with postoperative misalignment and rotation. METHODS: A total of 36 eyes of 36 patients with high myopia and myopic astigmatism who underwent implantable collamer lens V4c implantation were included in this study. Tilt, decentration, and rotation of the implantable collamer lens were assessed postoperatively at l week, 1 month, 3 months, and 6 months. Correlation analysis was used to identify the potential risk factors for implantable collamer lens tilt, decentration, and rotation at 6 months postoperatively. Higher-order aberration was measured to evaluate the effect of implantable collamer lens misalignment on visual quality at pupil diameters of 4.0 mm and 6.0 mm. RESULTS: The tilt and decentration at the last follow-up were 2.43 ± 1.35° and 0.278 ± 0.160 mm, respectively. There was a significant positive correlation between tilt and decentration (r = 0.31, P = 0.046). No significant correlation was detected between implantable collamer lens decentration and internal higher-order aberrations (P > 0.05). The degree of implantable collamer lens rotation (3.11 ± 2.00°) was significantly associated with the vault (r = - 0.422, P = 0.01), while it was positively associated with the preoperative anterior chamber depth (r = 0.36, P = 0.034). No significant correlation was found between postoperative astigmatism and rotation (r = - 0.07, P = 0.351). CONCLUSIONS: The implantable collamer lens V4c provides relatively stable misalignment and rotation after implantation. The ICL lens vault is a potential risk factor for postoperative implantable collamer lens rotation. The absolute value of decentration and tilt was relatively small, which showed no correlation with internal higher-order aberration in short-term observation.


Assuntos
Astigmatismo , Cristalino , Lentes Intraoculares , Miopia , Lentes Intraoculares Fácicas , Humanos , Implante de Lente Intraocular , Acuidade Visual , Miopia/diagnóstico , Miopia/cirurgia , Astigmatismo/diagnóstico , Astigmatismo/etiologia , Astigmatismo/cirurgia
16.
J Formos Med Assoc ; 122(2): 91-97, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36476674

RESUMO

This mini-review provides the practice guideline recommendations for ventilation of remodeled negative-pressure isolation wards for COVID-19 Patients. Remodeled "quasi-negative-pressure" isolation wards had been proved a feasible, inexpensive, safe, and effective measure to contain nosocomial outbreaks. We should first determine the minimum required ventilation volume of an isolation ward based on the severity of COVID-19 patients. Mechanical ventilation remains the mainstay for achieving the requirement, while the assistance of recirculation is also helpful. Beyond adequate ventilation volume, the "clean to less-clean" directional airflow remains the golden rule for the solution of indoor ventilation. The virus-laden exhaust should be treated with HEPA/UV device or be kept away from living organisms, buildings, and air inlets.


Assuntos
COVID-19 , Humanos , Isolamento de Pacientes , Ventilação , Hospitais , Surtos de Doenças
17.
Respir Care ; 68(3): 417-428, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36195349

RESUMO

Intermittent mandatory ventilation (IMV) is one kind of breath sequence used to classify a mode of ventilation. IMV is defined as the ability for spontaneous breaths (patient triggered and patient cycled) to exist between mandatory breaths (machine triggered or machine cycled). Over the course of more than a century, IMV has evolved into 4 distinct varieties, each with its own advantages and disadvantages in serving the goals of mechanical ventilation (ie, safety, comfort, and liberation). The purpose of this paper is to describe the evolution of IMV, review relevant supporting evidence, and discuss the rationales for each of the 4 varieties. Also included is a brief overview of the background information required for a proper perspective of the purpose and design of the innovations. Understanding these different forms of IMV is essential to recognizing the similarities and differences among many dozens of different modes of ventilation. This recognition is important for clinical application, education of caregivers, and research in mechanical ventilation.


Assuntos
Ventilação com Pressão Positiva Intermitente , Respiração Artificial , Humanos , Respiração
18.
Oncol Res ; 32(1): 163-174, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38188684

RESUMO

Hepatocellular carcinoma (HCC) is a leading cause of death worldwide. Current therapies are effective for HCC patients with early disease, but many patients suffer recurrence after surgery and have a poor response to chemotherapy. Therefore, new therapeutic targets are needed. We analyzed gene expression profiles between HCC tissues and normal adjacent tissues from public databases and found that the expression of genes involved in lipid metabolism was significantly different. The analysis showed that AKR1C3 was upregulated in tumors, and high AKR1C3 expression was associated with a poorer prognosis in HCC patients. In vitro, assays demonstrated that the knockdown of AKR1C3 or the addition of the AKR1C3 inhibitor indomethacin suppressed the growth and colony formation of HCC cell lines. Knockdown of AKR1C3 in Huh7 cells reduced tumor growth in vivo. To explore the mechanism, we performed pathway enrichment analysis, and the results linked the expression of AKR1C3 with prostaglandin F2 alpha (PGF2α) downstream target genes. Suppression of AKR1C3 activity reduced the production of PGF2α, and supplementation with PGF2α restored the growth of indomethacin-treated Huh7 cells. Knockdown of the PGF receptor (PTGFR) and treatment with a PTGFR inhibitor significantly reduced HCC growth. We showed that indomethacin potentiated the sensitivity of Huh7 cells to sorafenib. In summary, our results indicate that AKR1C3 upregulation may promote HCC growth by promoting the production of PGF2α, and suppression of PTGFR limited HCC growth. Therefore, targeting the AKR1C3-PGF2α-PTGFR axis may be a new strategy for the treatment of HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Aldo-Ceto Redutases/genética , Dinoprosta , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Linhagem Celular , Indometacina/farmacologia , Membro C3 da Família 1 de alfa-Ceto Redutase
19.
Int J Mol Sci ; 23(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35955552

RESUMO

Chronic inflammation caused by liver damage or infection plays an important role in the development and progression of hepatocellular carcinoma (HCC). The activation of Toll-like receptors 4 (TLR4) is involved in HCC tumorigenesis. Moreover, high TLR4 expression in HCC has been linked to poor prognosis. Although the expression of TLR4 in HCC is relatively low compared to hematopoietic cells, it is important to explore the molecular mechanism leading to the elevation of TLR4 in HCC. In this study, we aimed to investigate the positive regulating loop for TLR4 expression in HCC in response to chronic inflammation. Our results confirm that the mRNA expression of TLR4 and proinflammatory cytokines, including interleukin 6 (IL6) and C-C motif chemokine ligand 2 (CCL2), positively correlate in human HCC samples. High TLR4 expression in HCC is more susceptible to lipopolysaccharide (LPS); TLR4 activation in HCC provides growth and survival advantages and thus promotes tumorigenesis. It has been shown that the LIN28/let-7 microRNA (miRNA) axis is a downstream effector of the TLR4 signal pathway, and let-7 miRNA is a potential post-transcriptional regulator for TLR4. Thus, we investigated the correlation between TLR4 and LIN28A mRNA and let-7g miRNA in HCC clinical samples and found that the expression of TLR4 was positively correlated with LIN28A and negatively correlated with let-7g miRNA. Moreover, by culturing PLC/PRF5 (PLC5) HCC cells in low-dose LPS-containing medium to mimic chronic inflammation for persistent TLR4 activation, the mRNA and protein levels of TLR4 and LIN28A were elevated, and let-7g miRNA was decreased. Furthermore, the 3' untranslated region (3'UTR) of TLR4 mRNA was shown to be the target of let-7g miRNA, suggesting that inhibition of let-7g miRNA is able to increase TLR4 mRNA. While parental PLC5 cells have a low susceptibility to LPS-induced cell growth, long-term LPS exposure for PLC5 cells leads to increased proliferation, cytokine expression and stemness properties. In conclusion, our studies demonstrate positive feedback regulation for chronic TLR4 activation in the modulation of TLR4 expression level through the LIN28A/let-7g pathway in HCC and suggest a connection between chronic inflammation and TLR4 expression level in HCC for promoting tumorigenesis.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Carcinogênese/genética , Carcinoma Hepatocelular/metabolismo , Retroalimentação , Humanos , Inflamação , Lipopolissacarídeos/farmacologia , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , RNA Mensageiro/genética , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
20.
Respir Care ; 67(7): 857-862, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35610027

RESUMO

BACKGROUND: Critical-care ventilators provide patient circuit compensation (CC) to counteract the loss of volume due to patient circuit compliance. No studies show the effect of inspiratory efforts (indicating maximal value of the muscle pressure waveforms [Pmax]) on CC function. The goal of this study was to determine how Pmax affects volume delivery with or without CC for both volume control continuous mandatory ventilation with set-point targeting scheme (VC-CMVs) and pressure control continuous mandatory ventilation with adaptive targeting scheme (PC-CMVa) modes on the Servo-u ventilator. METHODS: A breathing simulator was programmed to represent an adult with moderate ARDS with different Pmax. It was connected to a ventilator set to VC-CMVs or PC-CMVa. The change in tidal volume (ΔVT) was defined as the difference between VT with CC on versus off. VT error was defined as the difference between the simulator displayed VT and the set VT with CC on versus off. RESULTS: For both VC-CMVs and PC-CMVa modes, ΔVT decreased as Pmax increased. The VT error decreased as Pmax increas-ed for VC-CMVs. In contrast, VT error increased on PC-CMVa mode as Pmax increased and peaked 39.0% for Pmax = 15 cm H2O. For both modes, the difference in VT errors for CC on versus CC off decreased as Pmax increased. CONCLUSIONS: CC corrected the delivered VT for volume lost due to compression in the patient circuit as expected. This compensation volume decreases as airway pressure drops due to patient Pmax.


Assuntos
Síndrome do Desconforto Respiratório , Ventiladores Mecânicos , Adulto , Humanos , Respiração com Pressão Positiva , Respiração Artificial , Síndrome do Desconforto Respiratório/terapia , Volume de Ventilação Pulmonar/fisiologia
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