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1.
Rev Sci Instrum ; 95(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38717266

RESUMO

In the field of precision industries, measuring micro-angular errors plays a crucial role in improving the accuracy of equipment. Therefore, this study aims to develop a two-degree-of-freedom (two-DOF) angular error measurement system for simultaneously measuring the assembly angle errors of the bond head in a die bonding machine. This system is based on the laser collimation method and constructed by using components such as a fiber laser and position-sensitive detectors. It utilizes the angular drift compensation of the laser beam and averaging function to improve the measurement accuracy. In addition, the mathematical model of the proposed system was established by using skew-ray tracing. Through experiments, the measuring accuracy of ±0.25 arcsec and measuring repeatability of 0.3 arcsec could be achieved.

2.
J Am Chem Soc ; 145(42): 23188-23195, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37820275

RESUMO

Inorganic molecular cages are emerging multifunctional molecular-based platforms with the unique merits of rigid skeletons and inherited properties from constituent metal ions. However, the sensitive coordination bonds and vast synthetic space have limited their systematic exploration. Herein, two giant cage-like clusters featuring the organic ligand-directed inorganic skeletons of Ni4[La74Ni104(IDA)96(OH)184(C2O4)12(H2O)76]·(NO3)38·(H2O)120 (La74Ni104, 5 × 5 × 3 - C2O4) and [La84Ni132(IDA)108(OH)168(C2O4)24(NO3)12(H2O)116]·(NO3)72·(H2O)296 (La84Ni132, 5 × 5 × 5 - C2O4) were discovered by a high-throughput synthetic search. With the assistance of machine learning analysis of the experimental data, phase diagrams of the two clusters in a four-parameter synthetic space were depicted. The effect of alkali, oxalate, and other parameters on the formation of clusters and the mechanism regulating the size of two n × m × l clusters were elucidated. This work uses high-throughput synthesis and machine learning methods to improve the efficiency of 3d-4f cluster discovery and finds the highest-nuclearity 3d-4f cluster to date by regulating the size of the n × m × l inorganic cages through oxalate ions, which pushes the synthetic methodology study on elusive inorganic giant cages in a significantly systematic way.

3.
J Am Chem Soc ; 145(35): 19333-19337, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37638550

RESUMO

The conventional approach toward molecules with large two-photon absorption (TPA) involves donor-acceptor conjugation. Herein we show a new strategy involving the use of hexa-branched nanographenes. We synthesized two hexa-branched nanographenes, one with six benzoaceanthrylene arms fused to the coronene core and the other with six pyrenyl arms fused to the coronene core. Neither of these hexa-branched nanographenes has a donor-acceptor structure, yet they exhibited high TPA values of 3.6 × 103 and 1.9 × 104 GM, respectively, which are the highest values recorded for heteroatom-free hydrocarbon molecules. Theoretical analysis suggests that the fused branched structures are responsible for the large TPA cross-section. These findings illustrate the importance of the topology of the fused conjugated skeleton in TPA and provide an alternative structural design toward large TPA.

4.
Cancer Med ; 12(8): 9559-9569, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36846977

RESUMO

BACKGROUND: Patients with a 5-year recurrence-free survival post liver resection for colorectal cancer liver metastases (CRLM) are considered to be potentially cured. However, there is a deficit of data on long-term follow-up and the recurrence status among these patients in the Chinese population. We analyzed real-world follow-up data of patients with CRLM who underwent hepatectomy, explored the recurrence patterns, and established a prediction model for a potential cure scenario. METHODS: Patients who underwent radical hepatic resection for CRLM during 2000-2016, with actual follow-up data for at least 5 years, were enrolled. The observed survival rate was calculated and compared among the groups with different recurrence patterns. The predictive factors for 5-year non-recurrence were determined using logistic regression analysis; a recurrence-free survival model was developed to predict long-term survival. RESULTS: A total of 433 patients were included, of whom 113 patients were found non-recurrence after 5 years follow-up, with a potential cure rate of 26.1%. Patients with late recurrence (>5 months) and lung relapse showed significantly superior survival. Repeated localized treatment significantly improved the long-term survival of patients with intrahepatic or extrahepatic recurrences. Multivariate analysis showed that RAS wild-type CRC, preoperative CEA <10 ng/ml, and liver metastases ≤3 were independent factors for a 5-year disease-free recurrence. A cure model was developed based on the above factors, achieving good performance in predicting long-term survival. CONCLUSIONS: About one quarter patients with CRLM could achieve potential cure with non-recurrence at 5-year after surgery. The recurrence-free cure model could well distinguish the long-term survival, which would aid clinicians in determining the treatment strategy.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Neoplasias Colorretais/patologia , População do Leste Asiático , Hepatectomia , Neoplasias Hepáticas/secundário , Recidiva Local de Neoplasia/cirurgia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
5.
J Surg Oncol ; 125(6): 1002-1012, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35171534

RESUMO

OBJECTIVE: To assess prognostic influences of RAS mutational status and primary tumor site on cases with colorectal liver metastasis (CRLM) who underwent hepatectomy. METHODS: Clinicopathological data of 762 patients with CRLM who underwent hepatectomy between January 2000 and November 2018 were retrospectively analyzed. The left-sided tumors (LST) included tumors located in the splenic flexure, descending colon, sigmoid colon, and rectum; while right-sided tumors (RST) included those located in the cecum, ascending colon, and transverse colon. RAS mutational status was determined using Sanger sequencing or next-generation sequencing, including KRAS (Codons 12, 13, and 61) and NRAS (Codons 12, 13, and 61), which were defined as wild-type (RASwt) and mutant-type (RASmut), respectively. Survival curves were plotted using the Kaplan-Meier plotter and compared by the log rank test. The clinicopathological data were analyzed using univariate and multivariate analyses. RESULTS: The 5-year overall survival (OS) in the LST group was longer than that in the RST group (OS: 47.1% vs. 31.0%, p = 0.000, respectively), and the OS in the RASwt group was longer compared with that in the RASmut group (OS: 53.6% vs. 24.0%, p = 0.000). Besides, overall survival of the patients after hepatectomy was alternative, which was stratified by primary tumor site, with the 1-, 3-, and 5-year survival rates of 93.1%, 62.1%, and 47.1% for patients with LST, and 91.1%, 42.8%, and 31.0% for patients with RST, respectively. OS and disease-free survival (DFS) were significantly different stratified by RAS mutational status, with the 1-, 3-, and 5-year rates of 96.9%, 67.9%, and 53.6% for patients with RASwt tumors, and 85.7%, 41.5%, and 24.0% for patients with RASmut tumors, respectively. The 1-, 3-, and 5-year DFS rates were 51.9%, 30.0%, and 26.7% for patients with RASwt tumors, and 35.8%, 18.2%, and 14.9% for patients with RASmut tumors, respectively. The results of multivariate analysis showed that RAS mutational status and primary tumor site were both independent influencing factors of OS. CONCLUSION: RAS mutational status and primary tumor site affect OS independently in CRLM patients undergoing hepatectomy. The worse prognosis of RST cannot be simply attributed to the imbalance of RAS mutational status in different primary tumor sites.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Mutação , Neoplasias Colorretais/genética , Neoplasias Colorretais/cirurgia , Hepatectomia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Prognóstico , Estudos Retrospectivos , Proteínas ras/genética
6.
Eur J Protistol ; 82: 125860, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34990900

RESUMO

The current study investigated the potential functions of amoeboid cell formation and migration in a thraustochytrid strain, Aurantiochytrium limacinum BL10. Our results showed that: (1) When the surface of an agar plate was inoculated with BL10, amoeboid cells mainly emerged on the periphery of isolated colonies. The amoeboid cells then migrated outwards to form small vegetative cell clusters, which favored rapid colony expansion. In addition, amoeboid cells were capable of self-recognition (i.e. they were able to distinguish BL10 from other thraustochytrid species), and could choose whether to evade (self colonies) or approach (non-self colonies). These observations indicated that amoeboid cells were employed by BL10 to help colonize empty territories and to outcompete other thraustochytrid species in previously colonized territories. (2) When the agar medium was soft, amoeboid cells were able to penetrate the surface and migrate throughout, thereby allowing BL10 to colonize the interior of the solid matrix. This finding suggested that amoeboid cell formation and migration may help Aurantiochytrium colonize the interior of solid matrices to obtain additional nutrients and spatial resources. The mechanisms underlying the regulation of amoeboid cell formation and migration as well as the extraordinary microbial social behaviors of BL10 are also discussed in this article.


Assuntos
Amoeba , Estramenópilas , Meios de Cultura
7.
J Clin Med ; 8(11)2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31717600

RESUMO

Using the Taguchi method to narrow experimental parameters, the antimicrobial efficiency of a cold atmospheric plasma jet (CAPJ) treatment was investigated. An L9 array with four parameters of CAPJ treatments, including the application voltage, CAPJ-sample distance, argon (Ar) gas flow rate, and CAPJ treatment time, were applied to examine the antimicrobial activity against Escherichia coli (E. coli). CAPJ treatment time was found to be the most influential parameter in its antimicrobial ability by evaluation of signal to noise ratios and analysis of variance. 100% bactericidal activity was achieved under the optimal bactericidal activity parameters including the application voltage of 8.5 kV, CAPJ-sample distance of 10 mm, Ar gas flow rate of 500 sccm, and CAPJ treatment time of 300 s, which confirms the efficacy of the Taguchi method in this design. In terms of the mechanism of CAPJ's antimicrobial ability, the intensity of hydroxyl radical produced by CAPJ positively correlated to its antimicrobial efficiency. The CAPJ antimicrobial efficiency was further evaluated by both DNA double-strand breaks analysis and scanning electron microscopy examination of CAPJ treated bacteria. CAPJ destroyed the cell wall of E. coli and further damaged its DNA structure, thus leading to successful killing of bacteria. This study suggests that optimal conditions of CPAJ can provide effective antimicrobial activity and may be grounds for a novel approach for eradicating bacterial infections.

8.
Toxicol Lett ; 284: 1-9, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29195901

RESUMO

Idiopathic pulmonary fibrosis (IPF) and tumor are highly similar to abnormal cell proliferation that damages the body. This malignant cell evolution in a stressful environment closely resembles that of epithelial-mesenchymal transition (EMT). As a popular EMT-inducing factor, TGFß plays an important role in the progression of multiple diseases. However, the drugs that target TGFB1 are limited. In this study, we found that triptolide (TPL), a Chinese medicine extract, exerts an anti-lung fibrosis effect by inhibiting the EMT of lung epithelial cells. In addition, triptolide directly binds to TGFß and subsequently increase E-cadherin expression and decrease vimentin expression. In in vivo studies, TPL improves the survival state and inhibits lung fibrosis in mice. In summary, this study revealed the potential therapeutic effect of paraquat induced TPL in lung fibrosis by regulating TGFß-dependent EMT progression.


Assuntos
Diterpenos/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibrose Pulmonar Idiopática/prevenção & controle , Paraquat/toxicidade , Fenantrenos/uso terapêutico , Fator de Crescimento Transformador beta1/metabolismo , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Compostos de Epóxi/farmacologia , Compostos de Epóxi/uso terapêutico , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Simulação de Acoplamento Molecular , Fenantrenos/farmacologia , Ligação Proteica
9.
Phys Chem Chem Phys ; 17(21): 14193-200, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-25959436

RESUMO

This study describes the use of a composite nitrate salt solution as a precursor to synthesize CeO2 and Gd2O3-doped CeO2 (GDC) nanoparticles (NPs) using an atmospheric pressure plasma jet (APPJ). The microstructures of CeO2 and GDC NPs were found to be cubical and spherical shaped nanocrystallites with average particle sizes of 10.5 and 6.7 nm, respectively. Reactive oxygen species, detected by optical emission spectroscopy (OES), are believed to be the major oxidative agents for the formation of oxide materials in the APPJ process. Based on the material characterization and OES observations, the study effectively demonstrated the feasibility of preparing well-crystallized GDC NPs by the APPJ system as well as the gas-to-particle mechanism. Notably, the Bader charge of CeO2 and Ce0.9Gd0.1O2 characterized by density function theory (DFT) simulation and AC impedance measurements shows that Gd helps in increasing the charge on Ce0.9Gd0.1O2 NPs, thus improving their conductivity and making them candidate materials for electrolytes in solid oxide fuel cells.

10.
AMB Express ; 2(1): 42, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-22883641

RESUMO

This study explored the influence of various culture conditions on the biomass, lipid content, production of docosahexaenoic acid (DHA), and fatty acid composition of Aurantiochytrium mangrovei strain BL10. The variables examined in this study include the species and concentration of salt, the concentrations of the two substrates glucose and yeast extract, the level of dissolved oxygen, the cerulenin treatment, and the stages of BL10 growth. Our results demonstrate that BL10 culture produces maximum biomass when salinity levels are between 0.2 and 3.0%. Decreasing salinity to 0.1% resulted in a considerable decrease in the biomass, lipid content, DHA production, and DHA to palmitic acid (PA) (DHA/PA) ratio, signifying deterioration in the quality of the oil produced. The addition of 0.9% sodium sulfate to replenish salinity from 0.1% to 1.0% successfully recovered biomass, lipid content and DHA production levels; however, this also led to a decrease in DHA/PA ratio. An increase in oxygen and cerulenin levels resulted in a concomitant decrease in the DHA to docosapentaenoic acid (DPA) (DHA/DPA) ratio in BL10 oil. Furthermore, the DHA/DPA and DHA/PA ratios varied considerably before and after the termination of cell division, which occurred around the 24 hour mark. These results could serve as a foundation for elucidating the biochemistry underlying the accumulation of lipids, and a definition of the extrinsic (environmental or nutritional) and intrinsic (cell growth stage) factors that influence lipid quality and the production of DHA by BL10.

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