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1.
Phys Rev Lett ; 132(15): 156201, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38683007

RESUMEN

In conventional systems, the coefficient of friction (COF) is typically positive, signifying a direct relationship between frictional and normal forces. Contrary to this, we observe that the load dependence of friction exhibits a unique bell-shaped curve when studying the frictional properties between graphite and α-Al_{2}O_{3} surfaces. As the applied normal force increases, the friction initially rises and then decreases. Finite element simulations reveal this behavior is due to edge detachment at the graphite/α-Al_{2}O_{3} interface as the normal force approaches a critical value. Because friction in superlubric contacts predominantly arises from edges, their detachment leads to a decrease in overall friction. We empirically validate these findings by varying the radii of curvature of the tips and the thicknesses of graphite flakes. This unprecedented observation offers a new paradigm for tuning COF in superlubric applications, enabling transitions from positive to negative values.

2.
Mol Clin Oncol ; 19(5): 85, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37809346

RESUMEN

Gastroenteropancreatic (GEP) neuroendocrine tumors (NETs) are one of the most common types of NETs, accounting for 65-75% of all NETs. However, epidemiological characteristics of patients with GEP-NETs in China are still lacking. The present retrospective study aimed to investigate the local epidemiology of GEP-NETs and assess the prognostic factors in China. The data of 267 patients with GEP-NETs who were admitted to the First Affiliated Hospital of Bengbu Medical College (Bengbu, China) and the Affiliated Hospital of West Anhui Health Vocational College (Lu'an, China) were retrospectively reviewed. The clinical and pathological characteristics of the patients, as well as follow-up information, were collected, and the 5-year survival rate was calculated. Kaplan-Meier curves and log-rank analysis were used to analyze the prognostic factors. The stomach (100/267; 37.5%) was the most common site of GEP-NETs and the liver (25/39; 64.1%) was the most common metastatic site. A total of 166 (62.2%) and 219 (82.0%) patients had positive results for chromogranin A (CgA) and synaptophysin (Syn), respectively. The percentage of patients with tumor grade G1, G2 and G3 was 33.3, 21.0 and 45.7%, respectively. The 5-year overall survival rate was 79.7%, and the age, tumor site, distant metastasis and tumor grading upon diagnosis were all prognostic factors. In conclusion, the present case series investigated the epidemiology and prognostic factors of GEP-NETs in China. CgA and Syn could be used as diagnostic markers for NETs and the stomach was the most common primary tumor site. Lymph node metastasis, tumor site, distant metastasis and tumor grading were important prognostic factors.

3.
Am J Transl Res ; 14(11): 8049-8063, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36505306

RESUMEN

OBJECTIVE: The purpose of this investigation was to study the expression profile and potential function of circular RNA (circRNA) and long noncoding RNA (lncRNA) in triple-negative breast cancer (TNBC). METHODS: RNA sequencing technology was used to detect differentially expressed circRNAs and lncRNAs between TNBC tissues and the adjacent tissue. The potential functions of these different RNAs were analyzed by GO and KEGG enrichment analysis by bioinformatics tools. We also selected and analyzed these key circRNAs and lncRNAs to verify their important functions in TNBC. RESULTS: A total of 139 differentially expressed circRNAs and 1001 lncRNAs were obtained. The co-expression analysis showed that the hub lncRNAs (OIP5-AS1, DRAIC) were associated with several tumors and mainly enriched in tumor metastasis. We also screened 5 circRNA-hosting genes (NTRK2, FNTA, BAPGEF2, MGST2, ADH1B) that were associated with the brain-derived neurotrophic factor (BDNF) receptor signaling pathway and cerebral cortex development, as well as AMPK and TGF-ß signaling pathway. CONCLUSION: We identified a large number of differentially expressed circRNAs and lncRNAs, which provide useful insight in understanding TNBC carcinogenesis.

4.
Artículo en Chino | MEDLINE | ID: mdl-34304516

RESUMEN

Objective:To explore the value of indocyanine green(ICG) combined with methylene blue in the identification of sentinel lymph nodes(SLNs) in patients diagnosed with papillary thyroid microcarcinoma(PTMC). Methods:Ninety patients were enrolled and were randomized into group A and group B with 45 patients in each group. ICG combined with methylene blue were injected into the thyroid in group A, and only methylene blue were injected into thyroid in group B. Blue-stained or fluorescent nodes observed using near-infrared fluorescence imaging systems were defined as SLNs. After SLNs were removed, central lymph nodes(CLNs) dissection was completed in both groups. The pathological data and postoperative outcomes were compared between two groups. Results:There were significantly more SLNs(2.93/2.17) and CLNs(4.51/3.89) were dissected in group A than in group B(P<0.05). There were no significant differences in sensitivity, accuracy and the false-negative rate according the SLNs in two groups(P>0.05), but group A has higher sensitivity and accuracy rates, and lower false-negative rate. There were no significant differences in the amount of blood loss, the amount of lymphatic drainage, and incidence of hoarseness and lymphatic leakage in two groups(P>0.05). In group A, the operating time was longer, and the rate of hypoparathyroidism was lower(P<0.05). Conclusion:Sentinel lymph nodes biopsy using ICG combined with methylene blue is feasible and safe for SLNs identification in PTMC patients. It is also clinically significant for the parathyroid gland protection.


Asunto(s)
Ganglio Linfático Centinela , Carcinoma Papilar , Colorantes , Estudios de Factibilidad , Humanos , Verde de Indocianina , Ganglios Linfáticos/diagnóstico por imagen , Azul de Metileno , Biopsia del Ganglio Linfático Centinela , Neoplasias de la Tiroides
5.
Langmuir ; 36(14): 3821-3825, 2020 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-32202117

RESUMEN

We investigated the interfacial instability of emulsion droplets via in situ measuring the oil/water interfacial tension (IFT) using the capillary suction method. The discrete phase of the oil-in-water emulsion contains a hydrophobic polymer (polystyrene, PS) and a fatty alcohol cosurfactant n-cetyl alcohol (CA) or n-octadecanol (OD), both of which were dissolved in an organic solvent (chloroform). The continuous phase is an aqueous solution of surfactant (sodium dodecyl sulfate, SDS). Upon removal of the organic solvent, the concentrations of CA and PS increase gradually, which induce a continual decrease of the IFT until the occurrence of interfacial instability. Micropipette tensiometry performed on an evaporating emulsion droplet reveals that interfacial instability is triggered when the IFT decreases close to ∼0.17 mN/m. As a result, micron particles with wrinkled surfaces can be obtained after the complete removal of the organic solvent. The effect of the initial concentration and alkyl chain length of the cosurfactant on the interfacial instability and surface roughness of the formed particles was studied. This study provides theoretical guidance for the preparation of micrometer-sized polymer particles with diverse morphologies via the interfacial instability of emulsion droplets.

6.
Mol Clin Oncol ; 9(5): 553-560, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30345051

RESUMEN

The aim of the present meta-analysis compared left colic artery (LCA) preservation with non-preservation in laparoscopic resection of rectal cancer in terms of feasibility, efficacy and safety. The PubMed, Ovid, Embase, Web of Science, CBM, CNKI, VIP and WanFang Data databases were searched prior to June 2017 for studies comparing LCA preservation and non-preservation in laparoscopic resection for rectal cancer. Two researchers screened the literature independently, extracted the data and evaluated the risk of bias. The study was performed using RevMan 5.3 software for meta-analysis. A total of 10 studies comparing LCA preservation and non-preservation in laparoscopic resection for rectal cancer were selected for this meta-analysis, with a combined study population of 1,471 patients. The results of the meta-analysis demonstrated that, when comparing LCA preservation with non-preservation in laparoscopic resection for rectal cancer, there were significant differences between the two groups in terms of operative time (P<0.01), estimated blood loss (P<0.01), percentage of neostomy (P<0.01), the number of retrieved lymph nodes (P<0.01), time to first postoperative exhaust (P<0.01) and amount of anastomotic leakage (P<0.01). However, there were no significant differences in postoperative hospital stay (P=0.28), incidence of recurrence (P=0.73) and incidence of metastasis (P=0.52). Therefore, compared with LCA non-preservation, patients in whom the LCA was preserved during laparoscopic resection for rectal cancer had a better prognosis. However, there was no difference in recurrence or metastasis between the two groups. Although the operative time and estimated blood loss were increased with LCA preservation, these may be reduced with improving proficiency of the operating surgeons. The conclusions of the present study require verification by larger samples and high-quality randomized controlled trials.

7.
J Lipid Res ; 53(9): 1877-89, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22661308

RESUMEN

Regulation of hepatic very low density lipoprotein (VLDL) assembly and maturation is crucial in controlling lipid homeostasis and in the development of metabolic disorders, including obesity, hepatic steatosis, and insulin resistance. Cideb, a member of cell death-inducing DFF45-like effector (CIDE) protein family, has been previously shown to promote VLDL lipidation and maturation. However, the precise subcellular location of Cideb-mediated VLDL lipidation and the factors modulating its activity remain elusive. In addition to its localization to endoplasmic reticulum (ER) and lipid droplets (LD), we observed that Cideb was also localized to the Golgi apparatus. Mature and lipid-rich VLDL particles did not accumulate in the Golgi apparatus in Cideb(-/-) livers. Interestingly, we observed that hepatic perilipin 2/adipose differentiation-related protein (ADRP) levels were markedly increased in Cideb(-/-) mice. Liver-specific knockdown of perilipin 2 in Cideb(-/-) mice resulted in the reduced accumulation of hepatic triglycerides (TAG), increased VLDL-TAG secretion, and the accumulation of mature TAG-rich VLDL in the Golgi apparatus. These data reveal that Cideb and perilipin 2 play opposing roles in controlling VLDL lipidation and hepatic lipid homeostasis.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Lipoproteínas VLDL/metabolismo , Hígado/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis/deficiencia , Ayuno , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Aparato de Golgi/metabolismo , Hepatocitos/citología , Hepatocitos/metabolismo , Lipoproteínas VLDL/química , Hígado/citología , Masculino , Proteínas de la Membrana/deficiencia , Proteínas de la Membrana/genética , Ratones , Especificidad de Órganos , Tamaño de la Partícula , Perilipina-2 , Fenotipo , Transporte de Proteínas , Triglicéridos/metabolismo
8.
Hepatology ; 56(1): 95-107, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22278400

RESUMEN

UNLABELLED: High levels of dietary saturated fat have been closely associated with the development of hepatic steatosis, but the factors that mediate this process remain elusive. Here, we observed that the level of cell death-inducing DNA fragmentation factor-alpha-like effector a (Cidea) expression was highly correlated with the severity of hepatic steatosis in humans. Overexpression of Cidea in mouse liver resulted in increased hepatic lipid accumulation and the formation of large lipid droplets (LDs). In contrast, mice with a Cidea deficiency had decreased lipid accumulation and alleviated hepatic steatosis when they received a high-fat-diet feeding or in ob/ob mice. Furthermore, the knockdown of Cidea in livers of ob/ob mice resulted in significantly reduced hepatic lipid accumulation and smaller LDs. Importantly, we observed that Cidea expression in hepatocytes was specifically induced by saturated fatty acids (FAs), and such induction was reduced when sterol response element-binding protein (SREBP)1c was knocked down. In contrast, the overexpression of SREBP1c restored the saturated FA-induced expression of Cidea. In addition, we observed that the stability of Cidea protein in hepatocytes increased significantly in response to treatment with FAs. CONCLUSION: Cidea plays critical roles in promoting hepatic lipid accumulation and in the development of hepatic steatosis by acting as a sensor that responds to diets that contain FAs.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/metabolismo , Ácidos Grasos/metabolismo , Hígado Graso/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Animales , Biopsia con Aguja , Modelos Animales de Enfermedad , Hígado Graso/genética , Expresión Génica , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Obesos , Distribución Aleatoria , Valores de Referencia , Sensibilidad y Especificidad
9.
Cell Metab ; 9(2): 177-90, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19187774

RESUMEN

Secretion of triacylglycerol-enriched very-low-density lipoproteins (VLDLs) from the liver is vital for maintaining plasma lipid homeostasis. However, the process of VLDL assembly and lipidation is not well characterized. Here, we observed that liver of Cideb null mice had higher levels of triacylglycerols accompanied by low level of VLDL secretion. Furthermore, VLDL particles secreted from hepatocytes of Cideb null mice have low levels of triacylglycerols but normal levels of apoB. We also observed that Cideb is localized to endoplasmic reticulum and lipid droplets. Importantly, we have identified apoB as a Cideb-interacting protein. By infecting adenoviruses expressing various Cideb truncations into hepatocytes of Cideb null mice, we found that Cideb requires both its apoB-binding and lipid droplet association domains to restore the secretion of triacylglycerol-enriched VLDL particles. Our data suggest that Cideb promotes the formation of triacylglycerol-enriched VLDL particles and provides a molecular insight into VLDL lipidation and maturation in hepatocytes.


Asunto(s)
Apolipoproteínas B/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismo , Lipoproteínas VLDL/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis/genética , Retículo Endoplásmico/metabolismo , Ratones , Ratones Noqueados , Triglicéridos/metabolismo
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