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1.
Small ; 20(22): e2307671, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38221752

RESUMO

The recent groundbreaking achievement in the synthesis of large-sized single crystal C60 monolayer, which is covalently bonded in a plane using C60 as building blocks. The asymmetric lattice structure endows it with anisotropic phonon modes and conductivity. If these C60 are arranged in form of 1D fiber, the improved manipulation of phonon conduction along the fiber axis could be anticipated. Here, thermal properties of C60-fiber, including thermal transfer along the C60-fiber axis and across the interlayer interface are investigated using molecular dynamic simulations. Taking advantage of the distinctively hollow spherical structure of C60 building blocks, the spherical structure deformation and encapsulation induced thermal reduction can be up to 56% and 80%, respectively. By applying external electronic fields in H2O@C60 model, its thermal conductivity decreases up to 60%, which realizes the contactless thermal regulation. ln particular, the thermal rectification phenomenon is discovered by inserting atoms/molecules in C60 with a rational designed mass-gradient, and its maximum thermal rectification factor is predicted to ≈45%. These investigations aim to achieve effective regulation of the thermal conductivity of C60-fibers. This work showcases the potential of C60-fiber in the realms of thermal management and thermal sensing, paving the way to C60-based functional materials.

2.
ACS Sens ; 9(5): 2499-2508, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38683974

RESUMO

Carbon nanotubes (CNTs) hold great promise in next-generation sensors because of their remarkable physical properties. Yet, maintaining precise stacking configurations of CNTs to make full use of their remarkable properties is challenging because of their susceptibility to spontaneous reconstruction. Inspired by the weaving technology, we propose a CNT-graphene nanoribbon hybrid woven model that can maintain the specific structure of CNTs to achieve their elaborately designed function. In this study, comprehensive molecular dynamics simulations are carried out to investigate the thermal stability of the CNT-graphene hybrid woven model, as well as their potential for pressure sensing applications by utilizing the unique response of thermal transport to mechanical deformation at heterojunctions. The thermal stability is sensitive to the size of the graphene nanoribbon, and the woven structure remains stable from 200-500 K when its width is greater than 2.0 nm. Moreover, it is exciting that the sensors are effective at predicting the shapes of externally loaded objects through the analysis of the thermal conductivity distribution, which can be derived from the relationship between the thermal conduction and the pressure. Our findings shed light on the bottom-up functional design of nanomaterials and expand wider applications of high-performance nanosensors in other related fields.


Assuntos
Grafite , Simulação de Dinâmica Molecular , Nanotubos de Carbono , Pressão , Nanotubos de Carbono/química , Grafite/química , Condutividade Térmica
3.
Front Mol Neurosci ; 17: 1366855, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38685914

RESUMO

As wireless communication devices gain popularity, concerns about the potential risks of environmental exposure to complex frequency electromagnetic radiation (EMR) on mental health have become a public health issue. Historically, EMR research has predominantly focused on single- frequency electromagnetic waves, neglecting the study of multi-frequency electromagnetic waves, which more accurately represent everyday life. To address these concerns, our study compared the emotional effects of single-frequency and dual-frequency EMR while exploring potential molecular mechanisms and intervention targets. Our results revealed that single-frequency EMR at 2.65 or 0.8 GHz did not induce anxiety-like behavior in mice. However, exposure to dual-frequency EMR at 2.65/0.8 GHz significantly led to anxiety-like behavior in mice. Further analysis of mouse sera revealed substantial increases in corticosterone and corticotrophin releasing hormone levels following exposure to 2.65/0.8 GHz EMR. Transcriptome sequencing indicated a significant decrease in the expression of Cnr1, encoding cannabinoid receptor 1 Type (CB1R), in the cerebral. This finding was consistently verified through western blot analysis, revealing a substantial reduction in CB1R content. Additionally, a significant decrease in the endocannabinoid 2-arachidonoylglycerol was observed in the cerebral cortex. Remarkably, administering the cannabinoid receptor agonist Win55-212-2 significantly alleviated the anxiety-like behavior, and the cannabinoid receptor antagonist AM251 effectively counteracted the anti-anxiety effects of Win55-212-2. In summary, our research confirmed that dual-frequency EMR is more likely to induce anxiety-like behavior in mice than single-frequency EMR, with implications for the hypothalamic-pituitary-adrenal axis and the endocannabinoid system. Furthermore, our findings suggest that Win55-212-2 may represent a novel avenue for researching and developing anti-EMR drugs.

4.
Front Microbiol ; 15: 1354989, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476943

RESUMO

Introduction: Hypothyroidism has been found to be influenced by gut microbiota. However, it remains unclear which a taxon of gut microbiota plays a key role in this function. Identifying the key bacteria affects hypothyroidism and through what mechanism will be helpful for the prevention of hypothyroidism through specific clinical pathways. Materials and methods: In Study A, 35 families and 130 genera of gut microbiota are used as exposures, with hypothyroidism as the outcome. The causal effect of the gut microbiota on hypothyroidism is estimated through two-sample Mendelian randomization. Combining the results of the two taxonomical levels, key taxa are selected, which in Study B are investigated for their causal association with multiple generally admitted causes of hypothyroidism and their more upstream factors. For validating and revealing the potential mechanism, enrichment analyses of the related genes and interacting transcription factors were performed. Results: In Study A, Defluviitaleaceae (OR: 0.043, 95% CI: 0.005-0.363, P = 0.018)/Defluviitaleaceae_UCG_011 (OR: 0.385, 95% CI: 0.172-0.865, P = 0.021) are significantly causally associated with hypothyroidism at both taxonomical levels. In Study B, Defluviitaleaceae family and Defluviitaleaceae_UCG_011 genus show the causal association with decreased thyroiditis (Family: OR: 0.174, 95% CI: 0.046-0.653, P = 0.029; Genus: OR: 0.139, 95% CI: 0.029-0.664, P = 0.043), decreased subacute thyroiditis (Family: OR: 0.028, 95% CI: 0.004-0.213, P = 0.007; Genus: OR: 0.018, 95% CI: 0.002-0.194, P = 0.013), decreased influenza (Family: OR: 0.818, 95% CI: 0.676-0.989, P = 0.038; Genus: OR: 0.792, 95% CI: 0.644-0.974, P = 0.027), and increased anti-influenza H3N2 IgG levels (Family: OR: 1.934, 95% CI: 1.123-3.332, P = 0.017; Genus: OR: 1.675, 95% CI: 0.953-2.943, P = 0.073). The results of the enrichment analysis are consistent with the findings and the suggested possible mechanisms. Conclusion: Defluviitaleaceae of the gut microbiota displays the probability of causally inhibiting the clinical pathway of "Influenza-Subacute Thyroiditis-Hypothyroidism" and acts as the potential probiotics to prevent influenza, subacute thyroiditis, and hypothyroidism.

5.
Sci Prog ; 107(1): 368504241228668, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38385346

RESUMO

OBJECTIVE: This study aimed to investigate the effects of low-dose radiation on the abdominal aorta of mice and vascular endothelial cells. METHODS: Wild-type and tumor-bearing mice were exposed to 15 sessions of low-dose irradiation, resulting in cumulative radiation doses of 187.5, 375, and 750 mGy. The effect on the cardiovascular system was assessed. Immunohistochemistry analyzed protein expressions of PAPP-A, CD62, P65, and COX-2 in the abdominal aorta. Microarray technology, Gene Ontology analysis, and pathway enrichment analysis evaluated gene expression changes in endothelial cells exposed to 375 mGy X-ray. Cell viability was assessed using the Cell Counting Kit 8 assay. Immunofluorescence staining measured γ-H2AX levels, and real-time polymerase chain reaction quantified mRNA levels of interleukin-6 (IL-6), ICAM-1, and Cx43. RESULTS: Hematoxylin and eosin staining revealed thickening of the inner membranes and irregular arrangement of smooth muscle cells in the media membrane at 375 and 750 mGy. Inflammation was observed in the inner membranes at 750 mGy, with a clear inflammatory response in the hearts of tumor-bearing mice. Immunohistochemistry indicated increased levels of PAPP-A, P65, and COX-2 post-irradiation. Microarray analysis showed 425 up-regulated and 235 down-regulated genes, associated with processes like endothelial cell-cell adhesion, IL-6, and NF-κB signaling. Cell Counting Kit 8 assay results indicated inhibited viability at 750 mGy in EA.hy926 cells. Immunofluorescence staining demonstrated a dose-dependent increase in γ-H2AX foci. Reverse transcription quantitative PCR results showed increased expression of IL6, ICAM-1, and Cx43 in EA.hy926 cells post 750 mGy X-ray exposure. CONCLUSION: Repeated low-dose ionizing radiation exposures triggered the development of pro-atherosclerotic phenotypes in mice and damage to vascular endothelial cells.


Assuntos
Células Endoteliais , Neoplasias , Humanos , Células Endoteliais/metabolismo , Células Endoteliais/efeitos da radiação , Molécula 1 de Adesão Intercelular/metabolismo , Conexina 43/genética , Interleucina-6/genética , Ciclo-Oxigenase 2/genética , Proteína Plasmática A Associada à Gravidez , Radiação Ionizante , Fenótipo
6.
Transl Lung Cancer Res ; 13(5): 965-985, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38854934

RESUMO

Background: Tumor metastasis commonly affects pleura in advanced lung cancer and results in malignant pleural effusion (MPE). MPE is related to poor prognosis, but without systematic investigation on different cell types and their crosstalk at single cell resolution. Methods: We conducted single-cell RNA-sequencing (scRNA-seq) of lung cancer patients with pleural effusion. Next, our data were integrated with 5 datasets derived from individuals under normal, non-malignant disease and lung carcinomatous conditions. Mesothelial cells were re-clustered and their interactions with epithelial cells were comprehensively analyzed. Taking advantage of inferred ligand-receptor pairs, a prediction model of prognosis was constructed. The co-culture of mesothelial cells and malignant epithelial cells in vitro and RNA-seq was performed. Epidermal growth factor receptor (EGFR) antagonist cetuximab was utilized to prevent the lung cancer cells' invasiveness. Spatial distribution of cells in lung adenocarcinoma patients' samples were also analyzed to validate our findings. Results: The most distinctive transcriptome profiles between tumor and control were revealed in mesothelial cells, which is the predominate cell type of pleura. Five subtypes were divided, including one predominately identified in MPE which was characterized by enriched cancer-related pathways (e.g., cell migration) along evolutionary trajectory from normal mesothelial cells. Cancer-associated mesothelial cells (CAMCs) exhibited varied interactions with different subtypes of malignant epithelial cells, and multiple ligands/receptors exhibited significant correlation with poor prognosis. Experimentally, mesothelial cells can increase the migration ability of lung cancer cells through co-culturing. EGFR was the only affected gene in cancer cells that exhibited interaction with mesothelial cells and was associated with poor prognosis. Using EGFR antagonist cetuximab prevented the lung cancer cells' increased invasiveness caused by mesothelial cells. Moreover, epithelial mitogen (EPGN)-EGFR interaction was supported through spatial distribution analysis, revealing the significant proximity between EPGN+ mesothelial cells and EGFR+ epithelial cells. Conclusions: Our findings highlighted the important role of mesothelial cells and their interactions with cancer cells in pleural metastasis of lung cancer, providing potential targets for treatment.

7.
Cell Biosci ; 14(1): 54, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38678227

RESUMO

BACKGROUND: Extensive hepatocyte mortality and the absence of specific medical therapy significantly contribute to the unfavorable prognosis of acute liver failure (ALF). Ferroptosis is a crucial form of cell death involved in ALF. In this study, we aimed to determine the impact of Mediator complex subunit 1 (Med1) on ferroptosis and its potential hepatoprotective effects in ALF. RESULTS: Med1 expression is diminished in the liver of lipopolysaccharide (LPS)/D-galactosamine (D-GalN)-induced ALF mice, as well as in hepatocytes damaged by H2O2 or TNF-α/D-GalN in vitro. Med1 overexpression mitigates liver injury and decreases the mortality rate of ALF mice by ferroptosis inhibition. The mechanism by which Med1 inhibits erastin-induced ferroptosis in hepatocytes involves the upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream antioxidant genes heme oxygenase-1 (HO-1), glutamate cysteine ligase catalytic (GCLC), and NAD(P)H quinone oxidoreductase 1 (NQO1). Furthermore, Med1 overexpression suppresses the transcription of proinflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the liver of mice with LPS/D-GalN-induced ALF. CONCLUSION: Overall, our research findings indicate that Med1 suppresses ferroptosis and alleviates liver injury in LPS/D-GalN-induced ALF through the activation of Nrf2. These findings substantiate the therapeutic viability of targeting the Med1-Nrf2 axis as a means of treating individuals afflicted with ALF.

8.
Mil Med Res ; 11(1): 60, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39169415

RESUMO

BACKGROUND: The diagnosis of tuberculous pleurisy (TP) presents a significant challenge due to the low bacterial load in pleural effusion (PE) samples. Cell-free Mycobacterium tuberculosis DNA (cf-TB) in PE samples is considered an optimal biomarker for diagnosing TP. This study aimed to evaluate the applicability of cf-TB testing across diverse research sites with a relatively large sample size. METHODS: Patients suspected of TP and presenting with clinical symptoms and radiological evidence of PE were consecutively enrolled by treating physicians from 11 research sites across 6 provinces in China between April 2020 and August 2022. Following centrifugation, sediments obtained from PE were used for Xpert MTB/RIF (Xpert) and mycobacterial culture, while the supernatants were subjected to cf-TB testing. This study employed a composite reference standard to definite TP, which was characterized by any positive result for Mycobacterium tuberculosis (MTB) through either PE culture, PE Xpert, or pleural biopsy. RESULTS: A total of 1412 participants underwent screening, and 1344 (95.2%) were subsequently enrolled in this study. Data from 1241 (92.3%) participants were included, comprising 284 with definite TP, 677 with clinically diagnosed TP, and 280 without TP. The sensitivity of cf-TB testing in definite TP was 73.6% (95% CI 68.2-78.4), significantly higher than both Xpert (40.8%, 95% CI 35.3-46.7, P < 0.001) and mycobacterial culture (54.2%, 95% CI 48.4-59.9, P < 0.001). When clinically diagnosed TP was incorporated into the composite reference standard for sensitivity analysis, cf-TB testing showed a sensitivity of 46.8% (450/961, 95% CI 43.7-50.0), significantly higher than both Xpert (116/961, 12.1%, 95% CI 10.2-14.3, P < 0.001) and mycobacterial culture (154/961, 16.0%, 95% CI 13.8-18.5, P < 0.001). The specificities of cf-TB testing, Xpert, and mycobacterial culture were all 100.0%. CONCLUSIONS: The performance of cf-TB testing is significantly superior to that of Xpert and mycobacterial culture methods, indicating that it can be considered as the primary diagnostic approach for improving TP detection. Trial registration The trial was registered on Chictr.org.cn (ChiCTR2000031680, https://www.chictr.org.cn/showproj.html?proj=49316 ).


Assuntos
DNA Bacteriano , Mycobacterium tuberculosis , Derrame Pleural , Tuberculose Pleural , Humanos , Tuberculose Pleural/diagnóstico , Feminino , Mycobacterium tuberculosis/genética , Estudos Transversais , Masculino , Pessoa de Meia-Idade , Adulto , Derrame Pleural/microbiologia , Derrame Pleural/diagnóstico , China , DNA Bacteriano/análise , Ácidos Nucleicos Livres/análise , Idoso , Sensibilidade e Especificidade
9.
Invest. clín ; 63(1): 70-80, mar. 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1534643

RESUMO

Abstract We aimed to compare the efficacy and safety of ultra-mini percutaneous nephrolithotomy (UMP) and retrograde intrarenal surgery (RIRS) for the management of lower calyceal stones. A group of 136 patients with a single lower calyceal stone (2-3 cm in diameter) was divided into the UMP or RIRS groups. The average operation time in the RIRS group was significantly longer than that in the UMP group, and the intraoperative blood loss in the former was markedly less than that in the latter. Besides, in the RIRS group, the decreased value of postoperative Hb was obviously lower, the postoperative hospital stay was evidently shorter, and the total hospitalization expenses were markedly less than those in UMP group were. Moreover, the success rate of the first-stage lithotripsy in the UMP group was notably higher than that in RIRS group. The RIRS group had an obviously lower VAS score but a markedly higher BCS score than the UMP group six hours after surgery. At 24 h after operation, the levels of serum CRP, TNF-α and IL -6 in patients in both groups were remarkably increased, and they were evidently lower in the RIRS group than those in the UMP group were. Three days after surgery, the levels of serum CRP, TNF-α and IL -6 were notably lower in the UMP group than those in RIRS group were. RIRS and UMP are safe and effective in the treatment of 2-3 cm lower calyceal stones. The first-stage UMP is characterized by a high stone-free rate (SFR), short operation time and low postoperative infection risk, while RIRS is associated with less blood loss and low total expenses.


Resumen Nuestro objetivo fue comparar la eficacia y seguridad de la nefrolitotomía percutánea ultramini (UMP) y la cirugía intrarrenal retrógrada (CRIR) en el manejo quirúrgico de los cálculos caliceales inferiores. Un grupo de 136 pacientes con un solo cálculo calicial inferior (2-3 cm de diámetro) se dividió en un grupo UMP o un grupo CRIR. El tiempo de operación promedio en el grupo CRIR fue significativamente más largo que en el grupo UMP, y la pérdida de sangre intraoperatoria en el primero fue marcadamente menor que en el segundo. Además, en el grupo CRIR, el valor disminuido de la Hb postoperatoria fue obviamente menor, la estancia hospitalaria postoperatoria fue evidentemente más corta y los gastos totales de hospitalización fueron notablemente menores que los del grupo UMP. Además, la tasa de éxito de la litotricia de primera etapa en el grupo UMP fue notablemente más alta que en el grupo CRIR. El grupo CRIR tuvo una puntuación VAS obviamente más baja pero una puntuación BCS marcadamente más alta que el grupo UMP a seos horas después de la operación. A las 24 h después de la operación, los niveles séricos de PCR, TNF-α e IL -6 en los pacientes de ambos grupos aumentaron notablemente y fueron evidentemente más bajos en el grupo CRIR que en el grupo UMP. Tres días después de la operación, los niveles séricos de PCR, TNF-α e IL -6 fueron notablemente más bajos en el grupo UMP que en el grupo CRIR. Los procedimientos CRIR y el UMP son seguros y eficaces en el tratamiento de cálculos caliciales inferiores de 2-3 cm. El UMP de primera etapa se caracteriza por tener una tasa libre de cálculo (SFR) alta, un tiempo de operación corto y un riesgo de infección posoperatorio bajo, y el RIRS se caracteriza por una menor pérdida de sangre y gastos totales bajos.

10.
Clin. transl. oncol. (Print) ; 26(3): 756-764, mar. 2024.
Artigo em Inglês | IBECS (Espanha) | ID: ibc-230805

RESUMO

There are controversial about the application of cancer-directed surgery (CDS) in patients with liver metastases from gastric cancer, with improved responses to chemotherapy and targeted treatments, the role of CDS in metastatic gastric cancer to the liver needs to be revisited. This study aimed to evaluate the effect of CDS on patients with liver metastases from gastric cancer. Data for patients with liver metastases from gastric cancer were extracted from the population-based Surveillance, Epidemiology, and End Results (SEER) database. A total of 958 individuals were enrolled, 285 in the CDS group and 673 in the non-cancer guided surgery (Non-CDS) group. Following propensity score matching (PSM) analysis at 1:1 in the two groups,285 were included in the survival analysis for each group. Kaplan–Meier values and Cox proportional risk models were used to estimate the effect of CDS on patients' prognoses. Compared with the Non-CDS group, the CDS group significantly prolonged the median overall survival from 4 months (95% confidence interval [CI] 3–5) to 11 months (95% CI 8–12), p value < 0.001. Overall survival (OS) at 1 year was higher in the CDS group than in the Non-CDS group, at 44% (95 CI 38–50) and 25% (95 CI 20–30), respectively. OS at 3 years was also higher in the CDS group than in the Non-CDS group, at 24% (95 CI 19–29) and 6% (95 CI 3–9), respectively. Multivariate analysis showed that Non-CDS (hazard ratio[HR] = 2.26, 95% CI 1.88–2.72, p value < 0.001) was an adverse independent prognostic factor for patients (AU)


Assuntos
Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Estudos Retrospectivos , Estudos Prospectivos , Qualidade de Vida , Prognóstico
11.
Rev. bras. farmacogn ; 28(6): 732-737, Nov.-Dec. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-977741

RESUMO

ABSTRACT The present study was designed to investigate the effect of FPZ, a total flavonoids ointment topical application from Pouzolzia zeylanica var. microphylla (Wedd.) Masam, Urticaceae, on skin infections in mice. FPZ ointment anti-infective effect was investigated on Staphylococcus aureus-induced skin abscess and skin ulcers in mice by evaluating the variation in abscess volume, histopathology of skin tissue and healing rate. Secondary, it is topical anti-inflammatory activities on carrageenan-induced hind paw edema in mice was estimated. Besides, FPZ ointment fingerprint was performed by using ultra-performance liquid chromatography and FPZ ointment chemical constituents were isolated and identified by repeated column chromatograph and spectroscopic methods. The results revealed that FPZ ointment topical application at the concentration of 2.5-10% could attenuate skin abscess and ulcers and accelerate wound healing, as compared with control group treated with vehicle (p < 0.05). The histological analysis indicated that FPZ ointment acted via inflammation inhibition, granulation promotion and epidermis formation. Moreover, FPZ ointment effectively inhibited carrageenan-induced paw edema in a dose-dependent manner, especially 10% FPZ which showed superior activities in comparison with dexamethasone used as reference drug. FPZ ointment topical application showed a significant anti-infective effect against pyogenic bacterial skin infection in mice.

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