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1.
Can J Infect Dis Med Microbiol ; 2024: 7502110, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38660494

RESUMEN

Introduction: The development of combinatorial adjuvants is a promising strategy to boost vaccination efficiency. Accumulating evidence indicates that manganese exerts strong immunocompetence and will become an enormous potential adjuvant. Here, we described a novel combination of Mn2+ plus aluminum hydroxide (AH) adjuvant that significantly exhibited the synergistic immune effect. Methodology. Initially, IsdB3 proteins as the immune-dominant fragment of IsdB proteins derived from Staphylococcus aureus (S. aureus) were prepared. IsdB3 proteins were identified by western blotting. Furthermore, we immunized C57/B6 mice with IsdB3 proteins plus Mn2+ and AH adjuvant. After the second immunization, the proliferation of lymphocytes was measured by the cell counting kit-8 (CCK-8) and the level of IFN-γ, IL-4, IL-10, and IL-17 cytokine from spleen lymphocytes in mice and generation of the antibodies against IsdB3 in serum was detected with ELISA, and the protective immune response was assessed through S. aureus challenge. Results: IsdB3 proteins plus Mn2+ and AH obviously stimulated the proliferation of spleen lymphocytes and increased the secretion of IFN-γ, IL-4, IL-10, and IL-17 cytokine in mice, markedly enhanced the generation of the antibodies against IsdB3 in serum, observably decreased bacterial load in organs, and greatly improved the survival rate of mice. Conclusion: These data showed that the combination of Mn2+ and AH significantly acted a synergistic effect, reinforced the immunogenicity of IsdB3, and offered a new strategy to increase vaccine efficiency.

2.
Front Optoelectron ; 17(1): 2, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38240874

RESUMEN

The utilization of the dispersive Fourier transformation approach has enabled comprehensive observation of the birth process of dissipative solitons in fiber lasers. However, there is still a dearth of deep understanding regarding the extinction process of dissipative solitons. In this study, we have utilized a combination of experimental and numerical techniques to thoroughly examine the breathing dynamics of dissipative solitons during the extinction process in an Er-doped mode-locked fiber laser. The results demonstrate that the transient breathing dynamics have a substantial impact on the extinction stage of both steady-state and breathing-state dissipative solitons. The duration of transient breathing exhibits a high degree of sensitivity to variations in pump power. Numerical simulations are utilized to produce analogous breathing dynamics within the framework of a model that integrates equations characterizing the population inversion in a mode-locked laser. These results corroborate the role of Q-switching instability in the onset of breathing oscillations. Furthermore, these findings offer new possibilities for the advancement of various operational frameworks for ultrafast lasers.

3.
Immun Inflamm Dis ; 11(7): e928, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37506158

RESUMEN

INTRODUCTION: Staphylococcus aureus seriously threatens human and animal health. IsdB137-361 of the iron surface determinant B protein (IsdB) from S. aureus exhibits the strong immunogenicity, but its immunoprotective effect is still to be further promoted. Because PEI-PLGA nanoparticles are generated by PEI conjugate with PLGA to develop great potential as a novel immune adjuvant, the immunogenicity of IsdB137-361 is likely be strengthened by PEI-PLGA. METHODS: Here, PEI-PLGA nanoparticles containing IsdB137-361 proteins were prepared by optimizing the entrapment efficiency. Mice were immunized with IsdB137-361 -PEI-PLGA nanoparticles to assess their anti-S. aureus effects. The level of IFN-γ, IL-4, IL-17, and IL-10 cytokines from spleen lymphocytes in mice and generation of the antibodies against IsdB137-361 in serum was assessed by ELISA, the protective immune response was appraised by S. aureus challenge. RESULTS: IsdB137-361 proteins loaded by PEI-PLGA were able to stimulate effectively the proliferation of spleen lymphocytes and increase the secretion of IFN-γ, IL-4, IL-17, and IL-10 cytokine from spleen lymphocytes, and significantly enhance generation of the antibodies against IsdB137-361 in serum, reduce the level of bacterial load in liver, spleen and kidney, and greatly improve the survival rate of mice after challenge. CONCLUSION: These data showed that PEI-PLGA nanoparticles can significantly enhance the immunogenicity of IsdB137-361 proteins, and provide an important reference for the development of novel immune adjuvant.


Asunto(s)
Nanopartículas , Infecciones Estafilocócicas , Humanos , Animales , Ratones , Staphylococcus aureus , Interleucina-10 , Interleucina-17 , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Interleucina-4 , Proteínas de la Membrana , Adyuvantes Inmunológicos , Citocinas , Infecciones Estafilocócicas/prevención & control
4.
Phys Rev Lett ; 130(15): 153801, 2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37115872

RESUMEN

Bound states of solitons ("molecules") occur in various settings, playing an important role in the operation of fiber lasers, optical emulation, encoding, and communications. Soliton interactions are generally related to breathing dynamics in nonlinear dissipative systems, and maintain potential applications in spectroscopy. In the present work, dichromatic breather molecules (DBMs) are created in a synchronized mode-locked fiber laser. Real-time delay-shifting interference spectra are measured to display the temporal evolution of the DBMs, that cannot be observed by means of the usual real-time spectroscopy. As a result, robust out-of-phase vibrations are found as a typical intrinsic mode of DBMs. The same bound states are produced numerically in the framework of a model combining equations for the population inversion in the mode-locked laser and cross-phase-modulation-coupled complex Ginzburg-Landau equations for amplitudes of the optical fields in the fiber segments of the laser cavity. The results demonstrate that the Q-switching instability induces the onset of breathing oscillations. The findings offer new possibilities for the design of various regimes of the operation of ultrafast lasers.

5.
Iran J Immunol ; 20(1): 57-66, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36932950

RESUMEN

Background: Staphylococcus aureus is an opportunistic pathogen responsible for various infections with diverse clinical presentation and severity. The α-hemolysin is a major virulence factor in the pathogenesis of S. aureus infections. Objective: To produce a chimeric fusion protein for hemolytic detection of the S. aureus isolates and as a component of a multi-antigen vaccine. Methods: The fused strategy employed a flexible linker to incorporate the possible B cell and T cell determinants into one chimera (HlaD). The humoral and cellular response to the HlaD in mice was assessed to reveal a non-significant difference compared with the full-length α-hemolysin mutant (Hla H35L). Results: The results of the protective effect, the mimetic lung cell injury, and bacterial clearness demonstrated that the mice vaccinated with the HlaD alleviated the severity of the infection of the S. aureus, and the HlaD could similarly function with Hla H35L. Conclusion: The chimeric fusion (HlaD) provided a diagnostic antigen for hemolysis of the S. aureus strains and a potential vaccine component.


Asunto(s)
Infecciones Estafilocócicas , Staphylococcus aureus , Animales , Ratones , Staphylococcus aureus/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Pulmón/metabolismo , Factores de Virulencia/metabolismo
6.
J Virol Methods ; 312: 114652, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36493528

RESUMEN

Orf is an acute and highly contracted human and animal infection caused by orf virus (ORFV), which mainly affects sheep, goats, and other species. Clinically, opportunistic or conditional pathogens such as Staphylococcus aureus (S. aureus) are often detected in cases of orf, which greatly increases the risk of disease progression and clinical death. It has been reported that TRAP gene products of S. aureus can broadly influence bacterial life and pathogenicity in vivo, and introduction of exogenous TRAP genes may help to inhibit the proliferation of bacteria. In order to achieve the combined control of ORFV and S. aureus, a novel approach to design a S. aureus TRAP gene vaccine using a live attenuated ORFV vector is proposed. In this study, CRISPR/Cas9 gene editing technology was used to disable vascular endothelial growth factor E of ORFV (VEGF-v) and introduced TRAP gene into this position. TRAP gene expression was detected in keratinocytes infected with recombinant virus. The construction and experimental verification of recombinant ORFV (ORFV-v/TRAP) will provide a reference for in-depth studies on the prevention and control of mixed infectious disease.


Asunto(s)
Ectima Contagioso , Virus del Orf , Animales , Humanos , Ovinos , Virus del Orf/genética , Sistemas CRISPR-Cas , Edición Génica , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Expresión Génica
7.
Front Cell Infect Microbiol ; 13: 1213694, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38259972

RESUMEN

A large amount of evidence shows that different kinds of microorganisms can jointly cope with environmental pressures including cell hosts. For example, in many cases, it has been found that secondary or mixed infection of animals caused by ORFV (an epitheliophilic Parapoxvirus) and bacteria (such as Staphylococcus aureus or Streptococcus) shows a mutual aid mode that indirectly leads to the deterioration of the disease. However, the lack of research on the co-pathogenic mechanism, including how to hijack and destroy the cell host in the pathological microenvironment, has hindered the in-depth understanding of the pathogenic process and consequences of this complex infection and the development of clinical treatment methods. Here, we summarized the current strategies of trapping cell hosts together, based on the previously defined ORFV-Host (O-H) system. The opportunistic invasion of S. aureus destroyed the delicate dynamic balance of the O-H, thus aggravating tissue damage through bacterial products (mediated by Agr), even causing sepsis or inducing cytokine storms. In fact, the virus products from its adaptive regulatory system (VARS) weaken the immune attacks and block molecular pathways, so that S. aureus can settle there more smoothly, and the toxins can penetrate into local tissues more quickly. This paper focuses on the main challenges faced by cell hosts in dealing with mixed infection, which provides a starting point for us to deal with this disease in the future.


Asunto(s)
Coinfección , Virus del Orf , Infecciones Estafilocócicas , Animales , Staphylococcus aureus , Síndrome de Liberación de Citoquinas
8.
J Cancer ; 13(11): 3258-3267, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36118528

RESUMEN

Peroxiredoxin 5 (PRDX5) is the member of Prxs family, widely reported to be involved in various types of cell death. We previously found that PRDX5 knockdown increases the susceptibility of cell death upon oxidative stress treatment. Ethyl ß-carboline-3-carboxylate (ß-CCE), an alkaloid extracted from Picrasma quassioides, has been reported to play a role in neuronal disease, but its anti-cancer potential on liver cancers remains unknown. Here, we studied the effect of PRDX5 on ethyl ß-carboline-3-carboxylate (ß-CCE)-induced apoptosis of hepatomas. High expression level of PRDX5 was deeply related with the postoperative survival of patients with liver cancer, indicating that PRDX5 may be a biomarker of live cancer processing. Moreover, PRDX5 over-expression in HepG2 cells significantly inhibited ß-CCE-induced cell apoptosis and cellular ROS levels as well as mitochondrial dysfunction. Signalling pathway analysis showed that ß-CCE could significantly up-regulate the ROS-dependent MAPK signalling, which were in turn boosts the mitochondria-dependent cell apoptosis. Moreover, PRDX5 over-expression could reverse the anti-cancer effects induced by ß-CCE in HepG2 cells. Our findings suggest that PRDX5 has a protective role on ß-CCE-induced liver cancer cell death and provides new insights for using its anti-cancer properties for liver cancer treatment.

9.
In Vivo ; 36(3): 1178-1187, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35478127

RESUMEN

BACKGROUND/AIM: Ethyl ß-carboline-3-carboxylate (ß-CCE) is one of the effective ingredients of Picrasma quassioides (P. quassioides). As a ß-carboline alkaloid, it can antagonize the pharmacological effects of benzodiazepines by regulating neurotransmitter secretion through receptors, thus affecting anxiety and physiology. However, its efficacy in cancer treatment is still unclear. MATERIALS AND METHODS: We explored the effect of b-CCE on SiHa cells using MTT assay, western blot, flow cytometry, LDH release, T-AOC, SOD, and MDA assays. RESULTS: We investigated the cytotoxicity of ß-CCE in SiHa cells and verified that ß-CCE could induce cell apoptosis in a time- and concentration-dependent manner. In this process, treatment with ß-CCE significantly increased the levels of cytoplasmic and mitochondrial reactive oxygen species (ROS), which disturb the oxidation homeostasis by regulating the total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity, and malondialdehyde (MDA) production. Notably, the addition of N-acetylcysteine (NAC) (ROS scavenger) effectively alleviated ß-CCE-induced apoptosis in SiHa cells. In addition, ß-CCE might activate the p38/MAPK signaling pathway, as the pre-treatment with SB203580 (p38 inhibitor) significantly reduced ß-CCE-induced apoptosis in SiHa cells. CONCLUSION: ß-CCE has an anti-tumor activity. It activates the p38/MAPK signaling pathway by increasing intracellular ROS levels, which subsequently induce SiHa cell apoptosis. Our results provide a novel therapeutic target for treatment of cervical cancer.


Asunto(s)
Neoplasias del Cuello Uterino , Apoptosis , Carbolinas/farmacología , Femenino , Humanos , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Superóxido Dismutasa/metabolismo , Neoplasias del Cuello Uterino/tratamiento farmacológico , Proteínas Quinasas p38 Activadas por Mitógenos
10.
Infect Genet Evol ; 98: 105220, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35066165

RESUMEN

Poxviruses are a family of specialized cytoplasm-parasitic DNA viruses that replicate and assembly in virus factory. In Parapoxvirus (PPV) genus, with the orf virus (ORFV) as a representative species of this genus, their behaviors are significantly different from that of Orthopoxvirus, and the plots of viral practical solutions for evading host immunity are intricate and fascinating, particularly to anti-host and host's antiviral mechanisms. In order to protect the virus factory from immune elimination caused by infection, PPVs attempt to interfere with multiple stress levels of host, mainly by modulating innate immunity response (IIR) and adaptive immunity response (AIR). Given that temporarily constructed by virus infection, ORFV-HOST (OH) system accompanied by viral strategies is carefully managed in the virus factory, thus directing many life-critical events once undergoing the IIR and AIR. Evolutionarily, to reduce the risk of system destruction, ORFV have evolved into a mild-looking mode to avoid overstimulation. Moreover, the current version of development also focus on recognizing and hijacking more than eight antiviral security mechanisms of host cells, such as the 2',5'-oligoadenylate synthetase (OAS)/RNase L and PKR systems, the ubiquitin protease system (UPS), and so on. In summary, this review assessed inescapable pathways as mentioned above, through which viruses compete with their hosts strategically. The OH system provides a panoramic view and a powerful platform for us to study the PPV-Host interaction, as well as the corresponding implications on a great application potential in anti-virus design.


Asunto(s)
Inmunidad Adaptativa , Ectima Contagioso/inmunología , Interacciones Huésped-Patógeno/inmunología , Inmunidad Innata , Virus del Orf/fisiología , Animales , Bovinos , Ectima Contagioso/virología , Humanos , Virus del Orf/genética , Ovinos
11.
Immun Inflamm Dis ; 9(3): 971-983, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34010502

RESUMEN

INTRODUCTION: Staphylococcus aureus (S. aureus) is a gram-positive opportunistic pathogen, there are currently no high effective vaccine against S. aureus in humans and animals, the development of an efficient vaccine remains an important challenge to prevent S. aureus infection. Here, we prepared Als3-Th-cell-epitope-Target of RNAIII Activating Protein (TRAP) (ATT) proteins plus the novel combined adjuvants to develop a promising vaccine candidate against S. aureus. METHODS: The recombinant pET-28a (+)-att plasmids were constructed, and the ATT proteins were expressed and obtained, then, ATT plus Freund's adjuvant or the novel combined adjuvants of cytosine-phosphate-guanosine oligodeoxynucleotides (CpG), muramyl dipeptides (MDP), and FIA were immunized in mice. After booster immunization, the levels of interferon-γ (IFN-γ), interleukin-4 (IL-4), IL-10 and IL-17A cytokine were evaluated, the humoral immune responses against TRAP were detected in mice, and the survival rate of mice was confirmed by challenge assay. RESULTS: The mice immunized with ATT plus Freund's adjuvant exhibited significantly higher level of IFN-γ, IL-4, IL-10, and IL-17A, and displayed the stronger humoral immune response against TRAP than control groups, importantly, the survival rate of these mice was significantly higher than control groups. In addition, compared with the control groups, ATT + CpG + MDP + FIA group was elicited significantly higher level of IFN-γ, IL-4, IL-10, and IL-17A and was triggered the stronger humoral immune responses against TRAP, moreover, generated the higher survival rate of mice. CONCLUSION: Als3 epitopes significantly enhanced TRAP immunogenicity. ATT plus the novel combined adjuvants of CpG, MDP, and FIA induced the strong immune response and protection against S. aureus, revealing the combination of CpG, MDP, and FIA adjuvant acts the synergistic effect.


Asunto(s)
Acetilmuramil-Alanil-Isoglutamina , Staphylococcus aureus , Animales , Epítopos , Inmunidad , Ratones , ARN Bacteriano
12.
J Microbiol Biotechnol ; 31(5): 667-675, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-33879639

RESUMEN

Streptococcus agalactiae is an important bacterial pathogen and causative agent of diseases including neonatal sepsis and meningitis, as well as infections in healthy adults and pregnant women. Although antibiotic treatments effectively relieve symptoms, the emergence and transmission of multidrug-resistant strains indicate the need for an effective immunotherapy. Effector T helper (Th) 17 cells are a relatively newly discovered subpopulation of helper CD4+ T lymphocytes, and which, by expressing interleukin (IL)-17A, play crucial roles in host defenses against a variety of pathogens, including bacteria and viruses. However, whether S. agalactiae infection can induce the differentiation of CD4+ T cells into Th17 cells, and whether IL-17A can play an effective role against S. agalactiae infections, are still unclear. In this study, we analyzed the responses of CD4+ T cells and their defensive effects after S. agalactiae infection. The results showed that S. agalactiae infection induces not only the formation of Th1 cells expressing interferon (IFN)-γ, but also the differentiation of mouse splenic CD4+ T cells into Th17 cells, which highly express IL-17A. In addition, the bacterial load of S. agalactiae was significantly increased and decreased in organs as determined by antibody neutralization and IL-17A addition experiments, respectively. The results confirmed that IL-17A is required by the host to defend against S. agalactiae and that it plays an important role in effectively eliminating S. agalactiae. Our findings therefore prompt us to adopt effective methods to regulate the expression of IL-17A as a potent strategy for the prevention and treatment of S. agalactiae infection.


Asunto(s)
Interleucina-17/inmunología , Infecciones Estreptocócicas/inmunología , Streptococcus agalactiae/fisiología , Células Th17/inmunología , Animales , Carga Bacteriana/efectos de los fármacos , Carga Bacteriana/inmunología , Linfocitos T CD4-Positivos/inmunología , Diferenciación Celular , Proliferación Celular , Citocinas/inmunología , Femenino , Interleucina-17/administración & dosificación , Interleucina-17/antagonistas & inhibidores , Ratones , Bazo/inmunología , Bazo/microbiología , Infecciones Estreptocócicas/microbiología , Células TH1/inmunología
13.
Res Vet Sci ; 136: 422-429, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33812285

RESUMEN

Glyceraldehyde-3-phosphate dehydrogenase C (GapC) of Streptococcus dysgalactiae (S. dysgalactiae) is a highly conserved surface protein that can induce a protective immune response against S. dysgalactiae infection. To investigate the immune response and protective efficacy induced by epitope-vaccines against S. dysgalactiae infection, we constructed epitope-vaccines GTB1, GB1B2, and GTB1B2 using a T cell epitope (GapC63-77, abbreviated as GT) and two B cell epitopes (GapC30-36, abbreviated as GB1, and GapC97-103, abbreviated as GB2), which were identified in GapC1-150 of S. dysgalactiae in tandem by a GSGSGS linker. BALB/c mice were immunized via an intramuscular injection with the epitope vaccines. The levels of the cytokines, IFN-γ, IL-4, and IL-17, secreted by splenic lymphocytes and the antibody levels in the sera of the immunized mice were detected by ELISA. The immunized mice were subsequently challenged with S. dysgalactiae, and the bacterial colonization in the immunized-mouse organs was examined using the plate counting method. The results showed that the level of the cytokines induced by GTB1B2 was lower than that induced by GapC1-150, but higher than that induced by other epitope vaccines. The level of IgG induced by GTB1B2 was lower than that induced by GapC1-150, but higher than the levels induced by other epitope vaccines. The bacterial colonization numbers in the organs of the mice immunized with GTB1B2 were higher those of the mice immunized with GapC1-150, but significantly lower than those from the mice immunized with other epitope-vaccines. Our results demonstrated that the T cell and B cell epitopes in the epitope-vaccines worked synergistically against bacterial challenge. The multi-epitope vaccine, GTB1B2, could induce stronger cellular and humoral immune responses, and provide a better protective effect against S. dysgalactiae infection.


Asunto(s)
Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Inmunogenicidad Vacunal , Vacunas Estreptocócicas/inmunología , Streptococcus/inmunología , Animales , Citocinas/inmunología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Epítopos de Linfocito B/inmunología , Epítopos de Linfocito T/inmunología , Femenino , Ratones , Ratones Endogámicos BALB C
14.
Opt Lett ; 45(22): 6246-6249, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-33186961

RESUMEN

Creeping solitons, which belong to the class of pulsating solitons, can be meaningful for fundamental physics owing to their fruitful nonlinear dynamics. Their characteristics in mode-locked lasers have been studied theoretically, but it is difficult to experimentally observe evolution dynamics in real time. Here, we have experimentally observed the temporal and spectral evolution dynamics of creeping solitons in a passively mode-locked fiber laser by employing time-lens and dispersive Fourier transform technique. With the aid of Raman amplification, the measured recording length of the time lens in the asynchronous mode could be substantially improved. Temporal soliton snaking motion and spectral breathing dynamics are experimentally obtained, confirming intrinsic feature of pulsation dynamics. These results display how single-shot measurements can offer new insights into ultrafast transient dynamics in nonlinear optics.

15.
Front Vet Sci ; 7: 538, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33094105

RESUMEN

Orf is a widespread contagious epithelial viral disease found particularly in most sheep breeding countries in the world. Recently, an orf virus (ORFV) strain OV-HLJ05 was isolated from an outbreak in northeast China. Three genes of interest including ORFV011 (B2L), ORFV059 (F1L), and ORFV132 (VEGF) of ORFV, were recruited to identify and genetically characterize this newly isolated virus. Amino acid (aa) sequence compared with the ORFV references listed in GenBank, both B2L and F1L of OV-HLJ05 showed less microheterogeneity from their references. In contrast, the VEGF gene was included in the NZ7-VEGF like group as previously considered by Mercer in 2002. Unexpectedly, further multiple VEGF matches were made, using 34 published sequences from China and India, resulting in 27 strains of the NZ7 members. Based on Karki's report in 2020, NZ7-VEGF like viruses are emerging more and more frequently in these two countries, damaging the Asian sheep industry. Obvious heterogeneity with the NZ2, insertion of two oligopeptides TATI(L)QVVVAI(L) and SSSS(S) motif were found in the NZ7-like VEGF protein. These VEGFs are divided mainly into two types and a significant increase in the number of hydrogen bonds within the NZ7-like VEGF dimers was observed. The NZ7-like ORFV apparently favors the goat as a host and an emphasis on this in future epidemiological and pathological studies should be considered, focusing on the NZ7-like virus.

16.
Opt Lett ; 45(17): 4678-4681, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32870830

RESUMEN

Optoacoustic interaction can be strongly enhanced in tiny core fibers, and it holds significant potential for stable harmonic mode-locking at gigahertz (GHz) and higher repetition rate. In this Letter, we propose and demonstrate a microfiber-assisted GHz harmonic mode-locking fiber laser, which is achieved by the enhanced optomechanical coupling between cavity modes in microfiber with the waist length of ∼16cm and the waist diameter of ∼1.56µm. The repetition rates can be stably locked at 2.3828 GHz and predominately locked at 1.7852 GHz, corresponding to the frequencies of radial R01 and torsional-radial TR21 acoustic modes, respectively. Our results provide novel insight into the design of a high-repetition-rate laser source and the application of microfibers in the optomechanical field.

17.
Opt Lett ; 45(17): 4835-4838, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32870870

RESUMEN

Real-time measurement of ultrafast pulses together with high temporal resolution and long recording length is an urgent requirement of all optical communication systems and nonlinear science. Here, external motion dynamics of soliton pairs in mode-locking ultrafast fiber lasers can be single-shot characterized with long recording length, by using an asynchronous four-wave-mixing (FWM)-based temporal magnifier (AFTM) system. Recording length of more than one thousand roundtrips can be achieved through the AFTM system. Temporal propagation dynamics of soliton pairs with tunable separations are observed, revealing that soliton pairs with narrower separation display vibration-like dynamics, while the two solitons with wider separation remain relatively unchanged. We believe our results will provide a promising solution for real-time measurement of ultrafast pulse and can offer novel insights for ultrafast transient dynamics in nonlinear optics.

18.
In Vivo ; 34(4): 1823-1833, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32606152

RESUMEN

BACKGROUND/AIM: Picrasma quassioides (P. quassioides) is used in traditional Asian medicine widely for the treatment of anemopyretic cold, eczema, nausea, loss of appetite, diabetes mellitus, hypertension etc. In this study we aimed to understand the effect of P. quassioides ethanol extract on SiHa cervical cancer cell apoptosis. MATERIALS AND METHODS: The P. quassioides extract-induced apoptosis was analyzed using the MTT assay, fluorescence microscopy, flow cytometry and western blotting. RESULTS: P. quassioides extract induced cellular apoptosis by increasing the accumulation of cellular and mitochondrial reactive oxygen species (ROS) levels and inhibiting ATP synthesis. Pretreatment with N-Acetylcysteine (NAC), a classic antioxidant, decreased the intracellular ROS production and inhibited apoptosis. In addition, the P38 MAPK signaling pathway is a key in the apoptosis of SiHa cells induced by the P. quassioides extract. CONCLUSION: The P. quassioides extract exerts its anti-cancer properties on SiHa cells through ROS-mitochondria axis and P38 MAPK signaling. Our data provide a new insight for P. quassioides as a therapeutic strategy for cervical cancer treatment.


Asunto(s)
Picrasma , Neoplasias del Cuello Uterino , Apoptosis , Femenino , Humanos , Potencial de la Membrana Mitocondrial , Mitocondrias/metabolismo , Picrasma/metabolismo , Especies Reactivas de Oxígeno , Transducción de Señal , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/genética , Proteínas Quinasas p38 Activadas por Mitógenos/genética
19.
Anticancer Res ; 40(7): 3819-3830, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32620621

RESUMEN

BACKGROUND: Picrasma quassioides (PQ) is a traditional Asian herbal medicine with anti-tumor properties that can inhibit the viability of HepG2 liver cancer cells. H-Ras is often mutated in liver cancer, however, the effect of PQ treatment on H-Ras mutated liver cancer is unclear. This study aimed to investigate the role of PQ on ROS accumulation and mitochondrial dysfunction in H-ras mutated HepG2 (HepG2G12V) cells. MATERIALS AND METHODS: PQ ethanol extract-induced HepG2G12V apoptosis was analyzed by the MTT assay, fluorescence microscopy, flow cytometry and western blotting. RESULTS: PQ treatment affected cell migration and colony formation in HepG2G12V cells. Cleaved-caspase-3, cleaved-caspase-9 and BCL2 associated agonist of cell death (BAD) expression levels were increased, while the levels of B-cell lymphoma-extra large (Bcl-xL) were decreased with PQ treatment. PQ treatment led to a reduction of H-Ras expression levels in liver cancer cells, thus reducing their abnormal proliferation. Furthermore, it led to increased expression levels of Peroxiredoxin VI, which regulates the redox signal in cells. CONCLUSION: Taken together these results provide a new functional significance for the role of PQ in treating HepG2G12V liver cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Neoplasias Hepáticas/tratamiento farmacológico , Mitocondrias Hepáticas/efectos de los fármacos , Extractos Vegetales/farmacología , Proteínas Proto-Oncogénicas p21(ras)/genética , Especies Reactivas de Oxígeno/metabolismo , Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Genes ras , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Picrasma/química , Proteínas Proto-Oncogénicas p21(ras)/biosíntesis
20.
Mol Med Rep ; 22(3): 1831-1838, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32705184

RESUMEN

Apoptosis of pancreatic ß­cells is involved in the pathogenesis of type I and II diabetes. Peroxiredoxin I (Prx I) serves an important role in regulating cellular apoptosis; however, the role of Prx I in pancreatic ß­cell apoptosis is not completely understood. In the present study, the role of peroxiredoxin 1 (Prx I) during streptozotocin (STZ)­induced apoptosis of pancreatic ß­cells was investigated. The expression level of Prx I was decreased by STZ treatment in a time­dependent manner, and apoptosis of Prx I knockdown MIN6 cells was increased by STZ stimulation, compared with untransduced MIN6 cells. Furthermore, an intraperitoneal injection of STZ increased pancreatic islet damage in Prx I knockout mice, compared with wild­type and Prx II knockout mice. AKT and glycogen synthase kinase (GSK)­3ß phosphorylation significantly decreased following Prx I knockdown in MIN6 cells. However, phosphorylated ß­catenin and p65 levels significantly increased after STZ stimulation, compared with untransduced cells. The results of the present study indicate that deletion of Prx I mediated STZ­induced pancreatic ß­cell death in vivo and in vitro by regulating the AKT/GSK­3ß/ß­catenin signaling pathway, as well as NF­κB signaling. These findings provide a theoretical basis for treatment of pancreatic damage.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Regulación hacia Abajo , Células Secretoras de Insulina/citología , Peroxirredoxinas/genética , Transducción de Señal/efectos de los fármacos , Estreptozocina/efectos adversos , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Diabetes Mellitus Experimental/inducido químicamente , Regulación de la Expresión Génica/efectos de los fármacos , Técnicas de Inactivación de Genes , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Ratones , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo
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