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1.
Opt Express ; 31(23): 39169-39181, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38018002

RESUMO

This paper proposes a novel three-dimensional hologram calculation method based on the angular spectrum approach, with the aim of reducing the noise generated during the hologram reconstruction process. The proposed algorithm divides the spatial domain into multiple layers and employs the angular spectrum method to propagate the image between these layers, thus avoiding the paraxial approximation. To enhance the quality of the hologram, an error iteration algorithm is utilized to alleviate the occurrence of aliasing errors when directly superimposing holograms. Moreover, constraint factors are introduced between different layers within the same region to effectively utilize spatial resources for multi-image reconstruction, thereby mitigating the noise caused by inter-layer crosstalk. The feasibility of the proposed method is demonstrated through numerical simulations and optical experiments, highlighting its potential applicability to a wide range of three-dimensional reconstruction algorithms.

2.
Appl Opt ; 61(25): 7393-7400, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256040

RESUMO

The diffraction characteristics of orthogonal gratings with variable duty cycles and phase modulation depths are analyzed by using a spatial light modulator. The calculation methods of the transmission function, far-field diffraction light field, and diffraction efficiency of orthogonal gratings are deduced in theory. Meanwhile, the influences of the duty cycle and phase modulation depth on the diffraction characteristics of the orthogonal grating are discussed. The simulation and experimental results verify the correctness of the theoretical derivation. This method can be widely used in the fields of an optical vortex array, laser parallel processing, optical computing, optical communication, and optoelectronic hybrid processing.

3.
Front Immunol ; 13: 888250, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35592333

RESUMO

Tumor protein 53 (TP53) mutation predicts an unfavorable prognosis in diffuse large B-cell lymphoma (DLBCL), but the molecular basis for this association remains unclear. In several malignancies, the cytidine deaminase apolipoprotein B mRNA editing enzyme catalytic subunit 3B (APOBEC3B) has been reported to be associated with the TP53 G/C-to-A/T mutation. Here, we show that the frequency of this mutation was significantly higher in relapsed/refractory (R/R) than in non-R/R DLBCL, which was positively associated with the APOBEC3B expression level. APOBEC3B overexpression induced the TP53 G/C-to-A/T mutation in vitro, resulting in a phenotype similar to that of DLBCL specimens. Additionally, APOBEC3B-induced p53 mutants promoted the growth of DLBCL cells and enhanced drug resistance. These results suggest that APOBEC3B is a critical factor in mutant p53-driven R/R DLBCL and is therefore a potential therapeutic target.


Assuntos
Linfoma Difuso de Grandes Células B , Proteína Supressora de Tumor p53 , Citidina Desaminase/metabolismo , Humanos , Linfoma Difuso de Grandes Células B/patologia , Antígenos de Histocompatibilidade Menor/genética , Mutação , Prognóstico , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
4.
Appl Opt ; 60(17): 5104-5109, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34143076

RESUMO

A flattop beam is useful in ultrafast laser processing. A laser beam shaping method for high energy utilization and uniformity is presented using a complex hologram displayed on a spatial light modulator. The hologram consists of a geometric mask, an external blazed grating, and internal gradient orthogonal gratings. The gradient orthogonal gratings can change the incident light energy distribution and obtain flattop beams with high energy utilization. Experimental results show that the presented method can obtain an arbitrary geometric shape with a steep edge and high uniformity. Meanwhile, the bigger the geometric mask size, the higher the energy utilization will be, and it is up to 78.70%.

5.
Front Neurol ; 11: 355, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32477242

RESUMO

Purpose: Surgical resection has been traditionally used as a treatment for cavernous sinus hemangioma (CSH). However, this is usually difficult due to tumor vascularity and results in complications especially in large and giant CSH (volume >20 cm3). Previous studies have reported that radiotherapy (RT) provides an alternative treatment modality for hemangiomas. However, the optimized dose and fractions which control CSH and also protect the cognitive function remain unclear. This study reports our experience in the management of symptomatic large and giant CSH. Methods: Fifty-four patients with symptomatic large (20 cm3 40 cm3, >4 cm in diameter) CSH were enrolled in a retrospective study between January 2007 and December 2018. The prescription dose to the target margin was 50 Gy in 25 fractions. Results: The mean pre-RT tumor volume was 60.9 cm3 which ranged from 20.2 to 230.5 cm3. The clinical data obtained was analyzed retrospectively following a mean follow-up period of 35.0 months which ranged from 1 to 140 months. All patients experienced tumor shrinkage within 3 months after radiotherapy. There was an average mean tumor reduction of 79.7% (range, 48.4-98.5%) with no patients experiencing tumor progression and recurrence. All the 54 patients experienced symptomatic improvement within 1 month to 12 months after radiotherapy. Within the entire follow up period, no patients experienced any form of permanent complications or symptomatic radiation toxicity. Neurocognitive impairment studies were conducted before and after radiotherapy on 28 patients while the studies were conducted after the last follow up in 40 patients. The cognitive function of all the participants had normal MoCA-scores of 28.25 pre-radiotherapy. The post-treatment MoCA-scores were also clinically stable (28.04, p = 0.78), and the average MoCA-score did not show any decline until the last follow-up (27.61, p = 0.13). Conclusion: The optimal dose and fractions of radiotherapy treatment for symptomatic large and giant cavernous sinus hemangioma remain unclear. This study, therefore, used a marginal dose of 50 Gy in 25 fractions in radiotherapy and this was proven to be effective and relatively safe in the treatment of symptomatic large and giant CSHs.

6.
Sci Rep ; 7(1): 4866, 2017 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-28687760

RESUMO

It has been reported that in patients with operable stage I non-small cell lung cancer (NSCLC), overall survival (OS) is better in those who undergo hypofractionated stereotactic radiation therapy (HSRT) than in those who undergo surgery. However, the reason that HSRT has a better OS has not been fully explored. Here, we analyzed reconstitution kinetics in immune cells in the peripheral blood of NSCLC patients after HSRT. We found that HSRT increased the frequency of total T cells, especially the proportion of CD8+ T cells, but decreased the frequency of inhibitory Tregs. Intracellular staining showed that after HSRT, peripheral CD8+ T cells were transformed into activated T cells, which express high levels of TNF-α, IFN-γ, granzyme B and IL-2. HSRT also increased the production of IL-2, TNF-α, and IFN-γ but down-regulated the production of TGF-ß in CD4+ T cells. The frequencies of naïve B cells and double-negative B cells were lower, while the proportions of MZ-like B cells, transitional B cells and plasmablast cells were higher after HSRT. Collectively, our results demonstrate that HSRT activates the peripheral immune response and indicate the dynamic variation in peripheral lymphocytes after HSRT, which is very important for optimizing combination treatments in clinical practice.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Reconstituição Imune/efeitos da radiação , Imunidade Celular/efeitos da radiação , Radiocirurgia/métodos , Idoso , Subpopulações de Linfócitos B/imunologia , Citocinas/metabolismo , Feminino , Humanos , Ativação Linfocitária/efeitos da radiação , Masculino , Subpopulações de Linfócitos T/imunologia
7.
Neurosci Lett ; 569: 99-103, 2014 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-24631568

RESUMO

It was reported that venlafaxine protects microvascular endothelial cells injury in several models. But the mechanisms of venlafaxine protects cell injury still poor understanding. Here, we shows that in the cultured human brain microvascular endothelial cells (HBMEC), we found that venlafaxine protects methylglyoxal (MGO)-induced cell injury, and the venlafaxine significant reduction in the level of reactive oxygen species, down-regulated expression of pro-apoptotic activated caspase-3 and Bax, increased BDNF release and expression of anti-apoptotic Bcl-2 in the cultured HBMEC. Furthermore, we found that venlafaxine inhibits MGO-induced phosphorylation of JNK. Moreover, venlafaxine increased AKT phosphorylation and the protective effects of venlafaxine was inhibited by PI3K/AKT inhibitor. These findings suggest that venlafaxine protects MGO-induced HBMEC injury through PI3K/AKT and JNK pathway as the potential underlying mechanisms of HBMEC injury in diabetes.


Assuntos
Antidepressivos/farmacologia , Apoptose , Encéfalo/irrigação sanguínea , Cicloexanóis/farmacologia , Células Endoteliais/efeitos dos fármacos , Microvasos/citologia , Fármacos Neuroprotetores/farmacologia , Aldeído Pirúvico/farmacologia , Linhagem Celular , Células Endoteliais/citologia , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Cloridrato de Venlafaxina
8.
J Clin Immunol ; 33(4): 767-74, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23435610

RESUMO

PURPOSE: T-helper (Th) cells abnormalities are considered to be associated with the pathogenesis of Systemic lupus erythematosus (SLE). Recently, The Th22 cells have been identified and implicated in the pathogenesis of autoimmune diseases such as Rheumatoid arthritis (RA), although therir role in Systemic lupus erythematosus (SLE) remains unclear. The present study intends to investigate their roles in SLE. METHODS: Clinical data were collected in 65 SLE patients and 30 healthy controls. The patients were divided into active and inactive groups. CD4(+)IFN-γ(-)IL-17(-)IL-22(+)Tcells (Th22 cells),CD4(+) IFN-γ(-)IL-22(-)IL-17(+)T cells (Th17 cells),and CD4(+) IFN-γ(+) (Th1 cells) were assayed by flow cytometry. Serum interleukin-22 (IL-22) and IL-17 levels were measured by enzyme-linked immunosorbent assay. RESULTS: The main observation focused on increased Th22 cells in patients with sole lupus skin disease and decreased Th22 cells in patients with sole lupus nephritis. Likewise, concentrations of serum IL-22 were increased in patients with sole lupus skin disease, and decreased in patients with sole lupus nephritis. Additionally, there was a positive correlation between the percentage of Th22 cells and IL-22 production. The percentage of Th17 cells or concentration of serum IL-17 correlated positively with Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). CONCLUSION: Th22 seems to be a more significant index to predict the tissue involvement of SLE than Th17, although Th17 may play a role in the activity of SLE.


Assuntos
Lúpus Eritematoso Sistêmico/imunologia , Subpopulações de Linfócitos T/imunologia , Células Th1/imunologia , Células Th17/imunologia , Adulto , Antígenos CD4/metabolismo , Separação Celular , Dermatite/diagnóstico , Dermatite/etiologia , Dermatite/imunologia , Feminino , Citometria de Fluxo , Humanos , Interferon gama/metabolismo , Interleucina-17/sangue , Interleucina-17/imunologia , Interleucinas/sangue , Interleucinas/imunologia , Lúpus Eritematoso Sistêmico/diagnóstico , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/etiologia , Nefrite Lúpica/imunologia , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , Prognóstico , Índice de Gravidade de Doença , Adulto Jovem , Interleucina 22
9.
J Asian Nat Prod Res ; 11(3): 219-28, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19408145

RESUMO

Berbamine, a natural compound from the plant Berberis amurensis, is a traditional Chinese medicine mainly used in stimulating normal hematopoiesis in clinic. Our previous studies demonstrated that berbamine has anti-leukemia activity. In this study, we investigated the anticancer activity of berbamine against human hepatocellular carcinoma (HCC) HepG2 cells in vitro and in vivo. Berbamine treatment decreased the cell growth in a dose-dependent manner with an IC(50) value of 34.5 +/- 0.5 microM. Flow cytometric analysis of apoptosis using Annexin V/propidium iodide staining showed that the percentage of apoptotic cells was increased in a time-dependent manner. Berbamine treatment increased the expression level of Fas and P53, caused depolarization of mitochondrial membrane and decrease of membrane potential, and activated caspase-3, -8, and -9 in HepG2 cells. Berbamine-induced apoptosis could be blocked by the broad caspase inhibitor z-VAD-fmk. HepG2 human HCC xenograft mice treated with berbamine showed a significant reduction in tumor growth rates compared to saline-treated mice. These studies suggest that berbamine exerts anticancer effects on human HCC HepG2 cells in vivo and in vitro, the induction of p53 and the activity of the Fas apoptotic system may participate in the anticancer activity of berbamine in HepG2 cells.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Benzilisoquinolinas/química , Benzilisoquinolinas/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacocinética , Apoptose/efeitos dos fármacos , Benzilisoquinolinas/farmacocinética , Berberina/química , Bisbenzimidazol/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Medicina Tradicional Chinesa , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Plantas Medicinais/química , Fatores de Tempo , Proteína Supressora de Tumor p53/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Receptor fas/metabolismo
10.
Zhongguo Zhong Yao Za Zhi ; 33(21): 2517-20, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19149263

RESUMO

OBJECTIVE: To study the effects of brucea javanica oil on the expression of vascular endothelial growth factor (VEGF) in A549 cell line. METHOD: A549 cells were incubated with different concentrations of brucea javanica oil (0.5, 1.25, 2.5, 5 g x L(-1) for 48 h respectively. VEGF level in supernatant was determined by VEGF ELISA kits and mRNA expression of VEGF was evaluated by RT-PCR. PMN in health volunteers was treated as control groups. RESULT: Supernatant VEGF protein and mRNA expression were significantly elevated in A549 cells compared with the mononuclear cells (120.73 vs 21.21, P < 0.05). Brucea javanica oil (2.5 g x L(-1)) could reduced supernatant VEGF protein in A549 cells (20.30 vs 120.73, P < 0.05), but had no effect on the expression of VEGF mRNA (1.0230 vs 0.9573). It was found that brucea javanica oil (5 g x L(-1)) significantly reduced VEGF mRNA expression (0.4682 vs 0.9573, P < 0.05). CONCLUSION: Brucea javanica oil can depress the VEGF mRNA expression and secretion in A549 cells, which may be one of the mechanisms of its antitumor effect.


Assuntos
Brucea/química , Regulação da Expressão Gênica/efeitos dos fármacos , Óleos de Plantas/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Medicamentos de Ervas Chinesas/farmacologia , Ensaio de Imunoadsorção Enzimática , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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