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1.
Nano Lett ; 24(1): 356-361, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38109180

RESUMO

Analog systems may allow image processing, such as edge detection, with low computational power. However, most demonstrated analog systems, based on either conventional 4-f imaging systems or nanophotonic structures, rely on coherent laser sources for illumination, which significantly restricts their use in routine imaging tasks with ambient, incoherent illumination. Here, we demonstrated a metalens-assisted imaging system that can allow optoelectronic edge detection under ambient illumination conditions. The metalens was designed to generate polarization-dependent optical transfer functions (OTFs), resulting in a synthetic OTF with an isotropic high-pass frequency response after digital subtraction. We integrated the polarization-multiplexed metalens with a polarization camera and experimentally demonstrated single-shot edge detection of indoor and outdoor scenes, including a flying airplane, under ambient sunlight illumination. The proposed system showcased the potential of using polarization multiplexing for the construction of complex optical convolution kernels toward accelerated machine vision tasks such as object detection and classification under ambient illumination.

2.
J Org Chem ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38327084

RESUMO

Transition-metal-catalyzed asymmetric cross-coupling represents a powerful strategy for C-C bond formation and the synthesis of enantiomerically pure molecules. Here, we report a dual nickel/photoredox-catalyzed enantioselective reductive cross-coupling of aryl halides with α-bromobenzoates, readily generated from aliphatic aldehydes, to provide diverse chiral secondary benzylic alcohols that are important motifs in bioactive natural products and pharmaceuticals. This dual catalytic system features mild conditions, good functional group tolerance, broad substrate scope, excellent enantiocontrol, and avoidance of stoichiometric metal reductants, presenting great potential for late-stage functionalization of complex molecules.

3.
J Org Chem ; 89(4): 2223-2231, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38326966

RESUMO

A nickel-catalyzed reductive anti-arylative cyclization of alkynyl enones with aryl halides has been developed. The reaction avoids the use of stoichiometric organometallic reagents and has a broad reaction scope and high functional group tolerance. This method offers an efficient way to access a variety of synthetically useful carbocycles that are widely found in many natural products and biologically active molecules.

4.
Bioorg Chem ; 153: 107826, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39299177

RESUMO

Receptor activator of nuclear factor-κB ligand (RANKL) is considered the principal regulator of osteoclast differentiation. Therefore, strategies interfering with the RANKL-RANK signaling pathway may effectively inhibit osteoclast differentiation and mitigate bone resorption. Consequently, RANKL has become a promising target for new drug design strategies. Despite extensive research on specific drugs and antibodies, only a few have shown efficacy in treating osteoporosis. To address this challenge, we aimed to explore new approaches for designing drugs for osteoporosis. In this study, a 3D quantitative structure-activity relationship (QSAR) pharmacophore model was built for RANKL with reference to known inhibitor IC50 values. The optimal pharmacophore model was then employed as a 3D query to screen databases for novel lead compounds. The obtained compounds were subjected to ADMET and TOPKAT analyses to predict drug pharmacokinetics and toxicity. Molecular docking and de novo evolution approaches were applied to verify the docking binding affinities of the compounds. Five candidate compounds were subjected to further in vitro analyses to assess their anti-osteoporotic effects, among which compound 4 demonstrated significant inhibitory activity, achieving an inhibitory rate of 92.6 % on osteoclastogenesis at a concentration of 10 µM. Subsequent molecular dynamics (MD) simulations to assess the stability and behavior of compound 4 and its evolved variant, ZINC00059014397_Evo, within the RANKL binding site revealed that the variant is a potential therapeutic agent for targeting osteoclasts. This study offers valuable insights for developing next generation RANKL inhibitors for osteoporosis treatments.

5.
Microb Pathog ; 180: 106112, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37059211

RESUMO

Sepsis is a systemic infection affects several organs, which needs novel therapy for the management of it, thus protective effect of Rhoifolin was estimated against sepsis. Cecal ligation and puncture (CLP) method was used to induce sepsis and thereafter mice were treated with rhoifolin (20 and 40 mg/kg, i.p.) for one week. Food intake and survival rate was determined sepsis mice, moreover liver function test and cytokines was estimated in the serum of sepsis mice. In the lung tissue homogenate, oxidative stress parameters were determined, histopathological analysis was performed in liver and lung tissue of sepsis mice. Food intake and percentage of survival was improved in rhoifolin treated group than sham group. Level of liver function enzyme and cytokine was reduced significantly in the serum of rhoifolin treated sepsis mice. Treatment with rhoifolin ameliorates the altered oxidative stress parameters, and mRNA expression of Toll-like receptor 4 (TLR-4) in lung tissue of sepsis mice. Histopathological changes were also reverse in rhoifolin treated group than sham group of mice. In conclusion, result of report indicates Rhoifolin treatment reduces oxidative stress and inflammation in CLP induced sepsis mice, as it regulates TLR4/MyD88/NF-κB pathway.


Assuntos
Fígado , Sepse , Camundongos , Animais , Fígado/patologia , Inflamação/patologia , Citocinas/metabolismo , Punções , Flavonoides/farmacologia , Sepse/tratamento farmacológico , Sepse/metabolismo , Ceco/patologia , Modelos Animais de Doenças
6.
Phys Rev Lett ; 130(12): 123801, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37027878

RESUMO

The combination of conventional polarization optical elements, such as linear polarizers and waveplates, is widely adopted to tailor light's state of polarization (SOP). Meanwhile, less attention has been given to the manipulation of light's degree of polarization (DOP). Here, we propose metasurface-based polarizers that can filter unpolarized incident light to light with any prescribed SOP and DOP, corresponding to arbitrary points located both at the surface and within the solid Poincaré sphere. The Jones matrix elements of the metasurface are inverse-designed via the adjoint method. As prototypes, we experimentally demonstrated metasurface-based polarizers in near-infrared frequencies that can convert unpolarized light into linear, elliptical, or circular polarizations with varying DOPs of 1, 0.7, and 0.4, respectively. Our Letter unlocks a new degree of freedom for metasurface polarization optics and may break new ground for a variety of DOP-related applications, such as polarization calibration and quantum state tomography.

7.
Ann Hepatol ; 17(2): 268-273, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29469049

RESUMO

INTRODUCTION: Radiofrequency ablation (RFA) is an effective and minimally invasive technique for the management of hepatic hemangiomas (HHs). This study aims to assess the safety and efficacy of laparoscopic RFA for HHs. MATERIAL AND METHODS: Forty-four patients with 50 hepatic hemangiomas (5-10 cm in diameter) undergoing laparoscopic RFA from January 2012 to May 2015 at three tertiary hospitals in China were retrospectively analyzed. RESULTS: Thirty-three patients with subcapsular hemangiomas were treated with a laparoscopic approach, and 11 patients with lesions in the liver parenchyma were treated with a combined laparoscopy and an ultrasound-guided percutaneous approach. No conversion to open surgery or two-step surgery occurred during the study period. Patients with small hemangiomas (< 7 cm) required a significantly shorter operating time (71.1 ± 20.18 min vs. 106 ± 23.55 min, p = 0.000) and fewer punctures compared with patients with large hemangiomas (> 7 cm) (4.61 ± 1.09 vs. 6.73 ±1.01, P < 0.05). According to the Dindo-Clavien classification, 15 patients experienced 34 Grade 1 complications, and two had complications of Grade 3a. All complications were resolved by conservative treatment. Forty-three (86.0%) HHs in 38 patients were completely ablated after RFA, and 7 (14.0%) HHs in 6 patients were incompletely ablated. All patients were followed up for 6-24 months (mean 15 ± 6 months). CONCLUSION: The data showed that laparoscopic RFA is an effective treatment for small (< 10 cm) HHs. While the incidence of postoperative complications remains high, the majority of complications are minor. Patients undergoing laparoscopic RFA for HHs, even for the small ones, should be carefully selected.


Assuntos
Hemangioma/cirurgia , Laparoscopia , Neoplasias Hepáticas/cirurgia , Ablação por Radiofrequência/métodos , Adulto , China , Tomada de Decisão Clínica , Feminino , Hemangioma/diagnóstico por imagem , Hemangioma/patologia , Humanos , Laparoscopia/efeitos adversos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Complicações Pós-Operatórias/etiologia , Ablação por Radiofrequência/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral , Ultrassonografia de Intervenção
8.
Dig Dis Sci ; 62(5): 1321-1326, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28251501

RESUMO

BACKGROUND: Laparoscopic common bile duct exploration (LCBDE) is being increasingly used for management of common bile duct (CBD) stones. Primary CBD closure has been reported to have better short-term outcomes compared to T-tube placement. However, primary CBD closure cannot be performed in all patients. AIM: This study aims to evaluate the short- and long-term outcomes of LCBDE with primary CBD closure in appropriately selected patients and compare them with T-tube drainage. METHODS: Retrospective analysis of patients undergoing LCBDE in our department from June 2011 to October 2014 was performed. Primary closure was performed in 52 patients (group A), and a T-tube was placed in 33 patients (group B). Patient demographics, intraoperative findings, postoperative stay, complications, and long-term follow-up data were recorded and compared. RESULTS: The mean operating time was much longer in group A compared to group B (113.92 vs. 95.92 min, p = 0.032). The overall complication rate (9.6 vs. 6.3%, p = 0.701) and hospital stay (4 vs. 5.11 days, p = 0.088) were similar in both groups. No patient required conversion to the open procedure. Bile leakage was more frequent in group A (5.78 vs. 0%, p = 0.279), but this was not statistically significant. All three patients with bile leakage were treated successfully by conservative measures and gradual drain withdrawal. On long-term follow-up, recurrent stones were detected in two patients in group A. No patient was found to develop CBD stricture. CONCLUSION: LCBDE and primary CBD closure has excellent short- and long-term outcomes when performed in appropriately selected patients.


Assuntos
Ducto Colédoco/cirurgia , Cálculos Biliares/cirurgia , Laparoscopia/métodos , Seleção de Pacientes , Técnicas de Fechamento de Ferimentos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
9.
Mol Cell Biochem ; 394(1-2): 199-208, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24894820

RESUMO

Streptococcus pneumoniae is an important pathogen of pneumonia in human. Human alveolar epithelium acts as an effective barrier and is an active participant in host defense against invasion of bacterial by production of various mediators. Sirtuin 1 (SIRT1), the prototypic class III histone deacetylase, is involved in the molecular control of lifespans and immune responses. This study aimed at examining the role of SIRT1 in mediating S. pneumoniae-induced human ß-defensin-2 (hBD2) and interleukin-8(IL-8) expression in the alveolar epithelial cell line A549 and the underlying mechanisms involved. A549 cells were infected with S. pneumoniae for indicated times. Exposure of A549 cells to S. pneumoniae increased the expressions of SIRT1 protein, hBD2 and IL-8 mRNA, and protein. The SIRT1 activator resveratrol enhanced S. pneumoniae-induced gene expression of hBD2 but decreased IL-8 mRNA levels. Blockade of SIRT1 activity by the SIRT1 inhibitors nicotinamide reduced S. pneumoniae-induced hBD2 mRNA expression but increased its stimulatory effects on IL-8 mRNA. S. pneumoniae-induced activation of extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase (MAPK). SIRT1 expression was attenuated by selective inhibitors of ERK and p38 MAPK. The hBD2 mRNA production was decreased by pretreatment with p38 MAPK inhibitor but not with ERK inhibitor, whereas the IL-8 mRNA expression was controlled by phosphorylation of ERK. These results suggest that SIRT1 mediates the induction of hBD2 and IL-8 gene expression levels in A549 cell by S. pneumoniae. SIRT1 may play a key role in host immune and defense response in A549.


Assuntos
Células Epiteliais/enzimologia , Células Epiteliais/microbiologia , Interleucina-8/metabolismo , Alvéolos Pulmonares/enzimologia , Alvéolos Pulmonares/microbiologia , Sirtuína 1/metabolismo , Streptococcus pneumoniae/patogenicidade , beta-Defensinas/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática , Ativadores de Enzimas/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Interações Hospedeiro-Patógeno , Humanos , Interleucina-8/genética , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/imunologia , RNA Mensageiro/metabolismo , Transdução de Sinais , Sirtuína 1/genética , Streptococcus pneumoniae/imunologia , Fatores de Tempo , Regulação para Cima , beta-Defensinas/genética , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
Light Sci Appl ; 13(1): 88, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600108

RESUMO

Spectroscopic ellipsometry is a potent method that is widely adopted for the measurement of thin film thickness and refractive index. Most conventional ellipsometers utilize mechanically rotating polarizers and grating-based spectrometers for spectropolarimetric detection. Here, we demonstrated a compact metasurface array-based spectroscopic ellipsometry system that allows single-shot spectropolarimetric detection and accurate determination of thin film properties without any mechanical movement. The silicon-based metasurface array with a highly anisotropic and diverse spectral response is combined with iterative optimization to reconstruct the full Stokes polarization spectrum of the light reflected by the thin film with high fidelity. Subsequently, the film thickness and refractive index can be determined by fitting the measurement results to a proper material model with high accuracy. Our approach opens up a new pathway towards a compact and robust spectroscopic ellipsometry system for the high throughput measurement of thin film properties.

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