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1.
Opt Express ; 32(6): 10577-10586, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571265

RESUMO

Optical vortex arrays (OVAs) are complex light fields with versatile structures that have been widely studied in large-capacity optical communications, optical tweezers, and optical measurements. However, generating OVAs with arbitrary structures without explicit analytical expressions remains a challenge. To address this issue, we propose an alternative scheme for customizing OVAs with arbitrary structures using an epicycle model and vortex localization techniques. This method can accurately generate an OVA with an arbitrary structure by pre-designing the positions of each vortex. The influence of the number and coordinates of the locating points on customized OVAs is discussed. Finally, the structures of the OVA and each vortex are individually shaped into specifically formed fractal shapes by combining cross-phase techniques. This unique OVA will open up novel potential applications, such as the complex manipulation of multiparticle systems and optical communication based on optical angular momentum.

2.
Opt Lett ; 49(9): 2213-2216, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691682

RESUMO

Optical vortex (OV) modulation is a powerful technique for enhancing the intrinsic degrees-of-freedom in structured light applications. Particularly, the lattices involving multiple OVs have garnered significant academic interest owing to their wide applicability in optical tweezers and condensed matter physics. However, all OVs in a lattice possess the same order, which cannot be modulated individually, limiting its versatile application. Herein, we propose, to our knowledge, a novel concept, called the hot-swap method, to design a switchable hybrid-order OV lattice, in which each OV is easily replaced by arbitrary orders. We experimentally generated the switchable hybrid-order OV lattice and studied its characteristics, including interferograms, retrieved phase, energy flow, and orbital angular momentum. Furthermore, the significant advantages of the switchable hybrid-order OV lattice are demonstrated through the independent manipulation of multiple yeast cells. This study provides a novel scheme for accurate control and modulation of OV lattices, which greatly facilitates the diverse applications of optical manipulation and particle trapping and control.

3.
J Opt Soc Am A Opt Image Sci Vis ; 41(4): 694-699, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568669

RESUMO

The degree of paraxiality (DOP) of a radially polarized twisted multi-Gaussian Schell-model (RPT MGSM) beam is discussed, and the influence of the source parameters on its DOP is studied. It is shown that the parameters of the beam source, including the boundary characteristic, the beam waist width, the coherence width of the source correlation, and the twist factor, have a significant impact on the DOP of the RPT MGSM beam. To explain the behaviors of the DOP, the far-field divergence angle of this beam is also discussed.

4.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(7): 840-843, 2024 Jul 10.
Artigo em Zh | MEDLINE | ID: mdl-38946369

RESUMO

OBJECTIVE: To explore the clinical phenotype and genetic basis of a child with Neutral lipid storage disease with myopathy (NLSDM). METHODS: A child who was admitted to the First Affiliated Hospital of Zhengzhou University in February 2021 for a history of elevated creatine kinase (CK) for over 2 months was selected as the study subject. Clinical and laboratory examinations were carried out, and the child was subjected to whole exome sequencing. Candidate variants were validated by Sanger sequencing of her family members. RESULTS: The patient, a 9-year-old female, had exhibited weakness in the lower limbs, elevated CK level, and refractory cardiomyotrophy. Genetic testing revealed that she has harbored c.32C>G (p.S11W) and c.516C>G (p.N172K) compound heterozygous variants of the PNPLA2 gene, which were respectively inherited from her mother and father. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were rated as likely pathogenic (PM1+PM2_Supporting+PP3+PP4). CONCLUSION: The c.32C>G (p.S11W) and c.516C>G (p.N172K) compound heterozygous variants of the PNPLA2 gene probably underlay the myasthenia gravis and elevated creatine kinase in this child.


Assuntos
Lipase , Erros Inatos do Metabolismo Lipídico , Doenças Musculares , Humanos , Feminino , Criança , Doenças Musculares/genética , Erros Inatos do Metabolismo Lipídico/genética , Lipase/genética , Mutação , Testes Genéticos , Sequenciamento do Exoma , Creatina Quinase/sangue , Linhagem , Fenótipo , Aciltransferases
5.
Opt Express ; 31(16): 26069-26077, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710476

RESUMO

We introduce a class of twisted sinc-correlation partially coherent array sources, by applying the construction theory of correlation function. Spectral density of such novel focused beam propagating in free space is analyzed. It is shown that the intensity distribution presents a good twisted effect and splitting phenomenon upon propagation. The array dimension, the intensity distribution and spatial distribution of the lobes can be flexibly regulated by altering the source parameters. We also explore the spatial evolution of multiple correlation singularities of this light field, where the phase distribution appears as a rotational spiral windmill profile during propagation. Furthermore, the coherence orbital angular momentum of the twisted source beam is investigated. These findings could be useful in the particle manipulation and free-space optical communication.

6.
Arch Biochem Biophys ; 736: 109523, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36682704

RESUMO

OBJECTIVE: Acute myeloid leukemia (AML) remains a common hematopoietic malignancy, and drug resistance greatly blunts the efficacy of chemotherapy in AML treatment. Adriamycin (ADM, also called doxorubicin), is one of the most widely used chemotherapeutics for treating cancers. Herein, we studied the molecular mechanisms underlying microRNA-188-5p (miR-188-5p)-mediated ADM resistance in AML. METHODS: Differentially expressed miRNAs were screened in normal and malignant hematopoietic cells by bioinformatics tools. MiR-188-5p expression in primary bone marrow CD34+ cells and AML cells was evaluated. AML/ADM cells were established using THP-1 and Kasumi-1 cells. The effect of miR-188-5p on the drug resistance in AML/ADM cells was examined by delivery of miR-188-5p-inhibitor. The binding relationship between TET1 and miR-188-5p was analyzed by ChIP, and the downstream target of miR-188-5p was predicted by bioinformatics analysis and validated by dual-luciferase assay. Finally, rescue experiments were carried out in vitro and in vivo. RESULTS: miR-188-5p was highly expressed in AML cells, and miR-188-5p-inhibitor sensitized the AML/ADM cells to ADM. Inhibition of TET1 reduced miR-188-5p promoter hydroxymethylation and downregulated miR-188-5p. miR-188-5p bound to the 3'UTR of PTEN to inhibit PTEN expression, and the PI3K/AKT signaling was activated upon inhibition of PTEN. Suppression of PTEN conferred resistance again to AML/ADM cells in the presence of miR-188-5p inhibitor. CONCLUSION: TET1 elevates miR-188-5p expression by promoting miR-188-5p promoter hydroxymethylation, and miR-188-5p inhibits PTEN expression to induce PI3K/AKT signaling pathway activation, leading to ADM resistance in AML.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , MicroRNAs/genética , MicroRNAs/metabolismo , Leucemia Mieloide Aguda/genética , Doxorrubicina/farmacologia , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Proliferação de Células , Oxigenases de Função Mista/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
7.
Ecotoxicol Environ Saf ; 252: 114615, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36773438

RESUMO

The diseases caused by Vibrio during shrimp breeding program have the risk of spreading in different aquatic areas through larvae transportation between different regions. Therefore, the population distribution and the virulence and antibiotic resistance risk of 5 pathogenic Vibrio in shrimp (Penaeus vannamei) breeding system in China were evaluated for the first time. A total of 418 isolates were recovered from shrimp, breeding water and biological baits samples, and 312 isolates were identified as Vibrio genus based on 16s rDNA, among which V. alginolyticus, V. harveyi, V. parahaemolyticus, V. cholerae and V. campbellii were the dominant species. And 10/20 kinds of virulence genes (chiA, luxR, vhh, tlh, chxA, sepro, flaA, vch, VAC and rpoS) were detected among the 5 Vibrio species. Multiple antibiotic resistance (MAR) index of the 5 dominant Vibrio isolates were 0.13-0.88 %, and 36.5 % isolates with MAR < 0.2. But the antibiotic resistance pattern abundance (ARPA) index ranged from 0.25 to 0.56, which indicated the antibiotic phenotypes of Vibrio species in the shrimp breeding system in China were homogeneity. Furthermore, resistance quotients (RQs) calculation results displayed that the dominant Vibrio species in the shrimp breeding system in China showed no or low selection pressure for resistance to cefoperazone/sulbactam, enrofloxacin, ciprofloxacin, fluoroquine, florfenicol, tetracycline and doxycycline. But only 5 resistance genes were detected, which were strA (43.8 %), strB (11.7 %), QnrVC (2.9 %), sul2 (8.8 %) and Int4 (8.8 %), respectively, and the antimicrobial resistance genotypes were not previously correlated with their phenotypes. The relevant research results provide theoretical basis for epizootic tracking in aquatic system in China, and targeting its final risk in aquatic ecosystem and public health perspectives.


Assuntos
Penaeidae , Vibrio , Animais , Antibacterianos/farmacologia , Penaeidae/genética , Virulência/genética , Ecossistema , Farmacorresistência Bacteriana/genética , Vibrio/genética
8.
Ecotoxicol Environ Saf ; 233: 113347, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35219956

RESUMO

Benzophenone-3 (BP-3) is widely used in a variety of cosmetics and is prevalent in drinking water or food, and women were under notable high exposure burden of BP-3. Reports show the associations between prenatal exposure to BP-3 and the risk of fetal loss, but its underlying mechanism remains largely unknown. Pregnant ICR mice were gavaged with BP-3 from gestational day (GD) 0 to GD 6 at doses of 0.1, 10 and 1000 mg/kg/day. The samples were collected on GD 12. Ultra-performance liquid chromatography coupled with mass spectrometry-based metabolomics was used to detect metabolome changes in fetal mice, the uterus and the placenta to identify the underlying mechanism. The results showed that the body weight and relative organ weights of the liver, brain and uterus of pregnant mice were not significantly changed between the control group and the treatment group. BP-3 increased fetal loss, and induced placental thrombosis and tissue necrosis with enhancement of platelet aggregation. Metabolomic analysis revealed that fructose and mannose metabolism, the TCA cycle, arginine and proline metabolism in the fetus, arginine and proline metabolism and biotin metabolism in the uterus, and arginine biosynthesis and pyrimidine metabolism in the placenta were the key changed pathways involved in the above changes. Our study indicates that exposure to BP-3 can induce placental thrombosis and fetal loss via the disruption of maternal and fetal metabolism in mice, providing novel insights into the influence of BP-3 toxicity on the female reproductive system.


Assuntos
Placenta , Efeitos Tardios da Exposição Pré-Natal , Animais , Benzofenonas , Feminino , Feto , Metabolômica , Camundongos , Camundongos Endogâmicos ICR , Gravidez
9.
Opt Express ; 29(24): 39419-39427, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809307

RESUMO

When the first-order radially polarized vortex beam propagates in an uniaxial crystal, the spin and the orbital angular momentum parts can be separated. It is called the optical spin-orbit Hall effect. In this study, we investigate the tight focusing of the radially polarized vortex beam theoretically and find the spatial separation of the spin and the orbital angular momentum parts occurs in the focal plane when the polarization order equals 1 and the vortex charge equals 1 (or -1). Moreover, when the initial phase of the polarization state takes π/2, the spatial separation of intensity in the focal plane corresponds to the spatial separation of the spin and the orbital angular momentum parts. This phenomenon can be considered as a manifestation of the optical spin-orbit Hall effect in the tight focusing of radially polarized vortex beam. Also, we show that, when the polarization order is greater than 1, the initial phase change of polarization state just leads to the rotation of the focal field and the spin and the orbital angular momentum density in the focal plane. Our results provide the potential application in the field of optical micro-manipulation.

10.
Opt Express ; 28(13): 18607-18615, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32672158

RESUMO

The controlled and continuous negative energy flow (from negative to positive) on the optical axis in the focal region is obtained by adjusting the polarization distribution of the input second-order radially polarized beam (the polarization topological charge is equal to 2). Moreover, the similar evolution of negative energy flow also can be achieved for the tightly focused vector beams with polarization topological charge -2. It is because both the beams with polarization topological charges 2 and -2 can possess the same polarization and spin flow density distributions with the help of the polarization modulation. The results provide a potential method for modulating the effects induced by the spin-orbit coupling in tight focusing of optical beam.

11.
Appl Opt ; 59(11): 3432-3439, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32400458

RESUMO

The behavior of the twisted electomagnetic (EM) Gaussian Schell-model array beams in anisotropic random turbulence is investigated. An example illustrates that a twisted EM source can produce lattice-like patterns in degree of polarization with rotation or not, which depends on the setting of the initial twist phase. One also finds that the anisotropy of the medium leads to an anisotropic beam spreading, and we can effectively limit such turbulence-induced effects by optimizing the initial twist and source correlation widths. Moreover, after transmitting through the turbulence for sufficiently long distances, the intensity and coherence are mainly affected by turbulence statistics; however, for the case of polarization, the initial twist plays a dominant role in determining its distribution profile.

12.
Plant Dis ; 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32870110

RESUMO

White clover (Trifolium repens L.) is an important perennial legume forage widely cultivated in China (Zhang et al. 2016). In April 2018, severe necrotic lesions on leaves were observed in a cultivated white clover field in Chongqing, China. Approximately 90% of plants in the field were affected. Leaf spots were amphigenous, dark-brown, elliptic to subcircular, with diameter ranging between 1 to 12 mm, well defined by brown margins and yellow halos. Severely infected leaves became withered and abscised. Stems and flowers were not affected by the disease. Symptomatic leaves were surface sterilized with 70% ethanol for 30 s followed by 0.1% HgCl2 treatment for 3 min, and rinsed in sterile water three times. Thereafter, tissue samples from margins of individual lesions were placed on potato dextrose agar (PDA) amended with 50 mg/L of chloramphenicol and incubated at 25℃ in the dark. An olivaceous gray fungal colony was consistently isolated (90.5% isolation frequency). After 15 days of incubation, subglobose, black pycnidia developed in the cultural medium. Conidia were hyaline, ellipsoid to oblong, nonseptate(n = 50), ranging from 4.0 to 7.5 µm long (5.6 ± 2.3µm) × 2.0 to 3.8 µm wide(2.8 ± 1.0 µm). On the basis of its morphological characteristics, the fungus was identified as Boeremia sp. (Aveskamp et al. 2010). To confirm the identity, the internal transcribed spacer region (ITS), large subunit ribosomal RNA (LSU), partial actin (ACT), RNA polymerase II second largest subunit (rpb2) and beta-tubulin (tub2) genes were amplified with primers ITS1/ITS4, LR0R/LR7, ACT-512F/ACT-783R, RPB2-5F2/fRPB2-7cR, and Btub2Fd/Btub4Rd, respectively, in eight representative isolates and sequenced(Aveskamp et al. 2009; Chen et al. 2015). BLAST results showed 100% identity of the ITS (506/506 nucleotides), LSU (966/966 nucleotides), ACT (244/244 nucleotides) and tub2 (297/297 nucleotides) sequences with those of B. exigua (KY419536, MK398746, EU880878, and MK514090) and 99.83% identity of those of the rpb2 (593/594 nucleotides) sequence with B. exigua (KT389572).Based on morphology and DNA sequence analysis, the associated fungus was identified as B. exigua. Representative sequences of one isolate (BT2-1) were deposited in GenBank (MN826339, MN836592, MT265217, MT265218 and MT265219). In a pathogenicity test, ten 2-month-old potted white clover plants were spray-inoculated with a spore and mycelial suspension (approximately 105 CFU/mL) and the control plants were inoculated with sterile distilled water. Plants were incubated in a greenhouse at 20 to 24°C under natural light and enclosed in plastic bags for the first 3 days to maintain high humidity. After 10 days, typical dark-brown lesions similar to those seen in naturally infected leaves developed on the inoculated leaves and not on the control plants. B. exigua was reisolated from the lesions, thus completing Koch's postulates. There is some evidence that B exigua is capable of invading seedling root tissue of white clover and causing necrotic lesions on roots (Skipp and Christensen,1982). However, to our knowledge, this is the first report of leaf spot on T. repens caused by B. exigua. This disease severely reduces forage quality and yield. Proper identification of the causal organism is essential in formulating management strategies.

13.
Opt Express ; 27(16): 22930-22938, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510577

RESUMO

In an optical vortex (OV) field, the orbital angular momentum (OAM) distribution strongly depends on the intensity, which results in difficulty in OAM independent modulation. To overcome this limitation, we propose a grafted optical vortex (GOV) via spiral phase reconstruction of two or more OVs with different topological charges (TCs). To remain the annular shape of the GOV's intensity, the Dirac δ-function is employed to restrict the energy in a ring. Theoretical analysis and manipulation experiments of polystyrene microspheres show that the magnitude and direction of the GOV's local OAM are controllable by modulating the grafted TCs while the intensity remains constant. The results of this work provide an ingenious method to control the local tangential force on the light ring, which will promote potential applications in optical trapping and rotating micro-particles.

14.
Opt Lett ; 44(6): 1379-1382, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30874655

RESUMO

Topological charge (TC) of an optical vortex (OV) is a crucial parameter. We propose two factors, namely, the phase jump factor and the phase gradient factor, to replace the parameter of TC through unwrapping the TC definition integral. Based on these two factors, we report on a novel OV, referred to as the remainder-phase optical vortex (ROV). The properties of the ROV are studied in depth by adjusting these two factors. Results show that the phase gradient factor determines the total orbital angular momentum (OAM), whereas the phase jump factor decides the number of split unit vortices and reshapes the structure of the OAM distribution. This work provides a novel OV with controllable OAM distribution, which will open up new applications such as particle manipulation, beam shaping, and micro-fabrication.

15.
Anal Chem ; 90(13): 8188-8195, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29874038

RESUMO

Ocular neovascularization can result in devastating diseases that lead to marked vision impairment and eventual visual loss. In clinical implementation, neovascular eye diseases are first diagnosed by fluorescein angiography and then treated by multiple intravitreal injections, which nevertheless involves vision-threatening complications, as well as lack of real-time monitoring disease progression and timely assessment of therapeutic outcomes. To address this critical issue, we herein present a kind of theranostic agents made of peptide-functionalized silicon nanoparticles (SiNPs), suitable for simultaneous ocular neovascularization imaging and therapy. Typically, in addition to negligible toxicity and high specific binding ability to human retinal microvascular endothelial cells tube formation, the cyclo-(Arg-Gly-Asp-d-Tyr-Cys) ( c-(RGDyC))-conjugated SiNPs (SiNPs-RGD) features efficacious antiangiogenic ability in wound healing migration, transwell migration, transwell invasion, and tube formation assays. Taking advantage of these unique merits, we further employ the SiNPs-RGD for labeling angiogenic blood vessels and neovascularization suppression, demonstrating obvious inhibition of new blood vessels formation in mouse corneas. These results suggest the SiNPs-RGD as a novel class of high-quality theranostic probes is suitable for simultaneous diagnosis and treatment in ocular neovascular diseases.


Assuntos
Nanopartículas/química , Oligopeptídeos/química , Oligopeptídeos/uso terapêutico , Imagem Óptica/métodos , Retina/fisiopatologia , Silício/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacocinética , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Linhagem Celular , Estabilidade de Medicamentos , Corantes Fluorescentes/química , Humanos , Células MCF-7 , Camundongos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/fisiopatologia , Oligopeptídeos/farmacocinética , Oligopeptídeos/farmacologia , Retina/diagnóstico por imagem , Retina/efeitos dos fármacos , Nanomedicina Teranóstica , Fatores de Tempo , Distribuição Tecidual
16.
Opt Express ; 26(18): 22965-22975, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184953

RESUMO

As a spatial structured light field, the optical vortex (OV) has attracted extensive attention in recent years. In practice, the OV lattice (OVL) is an optimal candidate for applications of orbital angular momentum (OAM)-based optical communications, microparticle manipulation, and micro/nanofabrication. However, traditional methods for producing OVLs meet a significant challenge: the OVL structures cannot be adjusted freely and form a close-packed arrangement, simultaneously. To overcome these difficulties, we propose an alternative scheme to produce close-packed OVLs (CPOVLs) with controllable structures. By borrowing the concept of the close-packed lattice from solid-state physics, CPOVLs with versatile structures are produced by using logical operations of expanding OV primitive cells combined with the technique of phase mask generation. Then, the existence of OAM states in the CPOVLs is verified. Furthermore, the energy flow and OAM distribution of the CPOVLs are visualized and analyzed. From a light field physics viewpoint, this work increases the adjustment dimensions and extends the fundamental understanding of the OVL, which will introduce novel applications.


Assuntos
Simulação por Computador , Gálio/química , Lasers , Luz , Modelos Químicos , Espalhamento de Radiação , Ressonância de Plasmônio de Superfície/métodos
17.
Opt Express ; 26(2): 651-662, 2018 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-29401947

RESUMO

We report a novel method to freely transform the modes of a perfect optical vortex (POV). By adjusting the scaling factor of the Bessel-Gauss beam at the object plane, the POV mode transformation can be easily controlled from circle to ellipse with a high mode purity. Combined with the modulation of the cone angle of an axicon, the ellipse mode can be freely adjusted along the two orthogonal directions. The properties of the "perfect vortex" are experimentally verified. Moreover, fractional elliptic POVs with versatile modes are presented, where the number and position of the gaps are controllable. These findings are significant for applications that require the complex structured optical field of the POV.

18.
Anticancer Drugs ; 29(7): 660-673, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29782351

RESUMO

Hexavalent chromium [Cr(VI)] is a common human carcinogen associated with lung cancer and other pulmonary diseases as exposure to excessive Cr(VI) induces malignant transformation in human lung epithelial cells. The mechanism underlying its carcinogenicity is unclear in terms of how it facilitates metastases. Cr(VI) compounds are reported to briefly promote cell migration in a concentration-dependent manner and oncogene liver kinase B1 (LKB1) was reduced in Cr(VI)-transformed cells. Overexpression of LKB1 in Beas-2B-Cr [Cr(VI) malignantly transformed Beas-2B cells] suppressed cell migration and invasion and inactivated FAK, Src, MMP-2, GSK3ß, ß-catenin, and HEF1, which contribute to cell migration and invasion. Silencing LKB1 with siRNA promoted migration and invasion, and activated these downstream proteins. Long-term exposure to Cr(VI) enhanced the migration and invasiveness of Beas-2B cells and reduced the expression of LKB1, while activating these proteins as mentioned above. Data suggest that LKB1 may regulate downstream proteins such as FAK, Src, MMP-2, GSK3ß, ß-catenin, and HEF1, and affect the migration and invasiveness of Beas-2B-Cr cells.


Assuntos
Movimento Celular/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Cromo/toxicidade , Células Epiteliais/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/patologia , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos Nus , Invasividade Neoplásica
19.
Opt Lett ; 42(1): 135-138, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28059197

RESUMO

We propose a method to determine the topological charge (TC) of a perfect vortex. With the phase shift technique, the perfect vortex and its conjugate beam exactly overlap and interfere. Consequently, the TC of a perfect vortex is determined by counting the number of interference fringes. This proposed method enables in situ determination of the TC of the perfect vortex without the need for additional optical elements, and it is immune to environmental vibration and parasitic interference.

20.
Anticancer Drugs ; 28(4): 446-456, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28125432

RESUMO

Apigenin (APG), a widely distributed flavonoid in vegetables and fruits, with low toxicity, and a nonmutagenic characteristic, has been reported to have many targets. Evidence indicates that APG can inhibit the proliferation, migration, invasion, and metastasis of some tumor cells, but the mechanism, specifically in lung cancer, is unclear. The phosphoinositide 3-kinase (PI3K)/Akt signaling pathway regulates a diverse set of cellular functions relevant to the growth and progression of lung cancer, including proliferation, survival, migration, and invasion. Our results showed that APG exerted anti-proliferation, anti-migration, and anti-invasion effects in A549 human lung cancer cells by targeting the PI3K/Akt signaling pathway. 3-(4, 5-dimethylthiszol-2-yl)-2, 5-diphenytetrazolium bromide assay and colony formation assay showed that APG suppressed cell proliferation in a dose-dependent and time-dependent manner. Cell motility and invasiveness were assayed using a wound healing and Transwell assay, suggesting that APG inhibited the migration and invasion of A549 cells. Western blot analyses were carried out to examine the Akt signaling pathways. The results confirmed that APG decreased Akt expression and its activation. Then, cells were transfected with Akt-active and Akt-DN plasmids separately. The migration and invasion of A549 cells were significantly changed, constitutively activating Akt or knocking down Akt, indicating that APG can suppress the migration and invasion of lung cancer cells by modulating the PI3K/Akt signaling pathway. Furthermore, the results indicated that APG not only suppressed phosphorylation of Akt, thereby preventing its activation, but also inhibited its downstream gene expression of matrix metalloproteinases-9, glycogen synthase kinase-3ß, and HEF1. Together, APG is a new inhibitor of Akt in lung cancer and a potential natural compound for cancer chemoprevention.


Assuntos
Apigenina/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Células A549 , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Terapia de Alvo Molecular , Invasividade Neoplásica , Proteína Oncogênica v-akt , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
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