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1.
Skin Res Technol ; 30(4): e13694, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38606725

RESUMO

BACKGROUND: Exosomes and other secretory membrane vesicles are collectively referred to as extracellular vesicles (EVs). Relevant data indicate that stem cell-derived extracellular vesicles (SC-EVs) play a critical role in angiogenesis by transmitting crucial information such as proteins, second messengers, and genetic material between cells. Therefore, this study aimed to map current trends on SC-EVs for angiogenesis and provide directions for future research to advance this important field. METHODS: We conducted a thorough search for relevant studies on SC-EVs for angiogenesis from 2003 to 2023 using the Web of Science database. Subsequently, we used VOSviewer and CiteSpace to analyze the collected data. RESULTS: A total of 2359 relevant publications, which included original articles and reviews, related to the role of SC-EVs in angiogenesis were screened in this study based on the search strategy. China and the United States were leading in this field, with China having a higher output in terms of publications and citations (1172, 43681). Also, the top five universities were located in China, with Shanghai Jiao Tong University having the highest output. Stem Cell Research & Therapy and International Journal of Molecular Sciences, are prominent platforms for researchers in this field to share their findings and advancements, and they had most of published studies on SC-EVs for angiogenesis. The results derived from the cluster analysis suggested that future investigations should predominantly prioritize studying the involvement of SC-EVs in angiogenesis across various diseases, with a specific emphasis on skin wound healing. CONCLUSION: In this comprehensive review, global trends in SC-EVs for angiogenesis were analyzed. The analysis of journals, institutions, references, and keywords could assist researchers in deciding on the direction of research. The role of SC-EVs in promoting angiogenesis during wound healing and repair represents an emerging research focus.


Assuntos
Vesículas Extracelulares , Pesquisa com Células-Tronco , Humanos , Angiogênese , Bibliometria , China , Estados Unidos
2.
Opt Express ; 31(2): 1557-1566, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785188

RESUMO

The filamentation of the femtosecond vortex beam has attracted much attention because of the unique filamentation characteristics, such as annular distribution and helical propagation, and related applications. The critical power for self-focusing of the femtosecond vortex beams is a key parameter in the filamentation process and applications. But until now, there is no quantitative determination of the critical power. In this work, we experimentally determine the self-focusing critical power of femtosecond vortex beams in air by measuring fluorescence using a photomultiplier tube. The relation between the self-focusing critical power and the topological charge is further obtained. Our work provides a simple method to determine the self-focusing critical power not only for vortex beams but also for Airy, Bessel, vector, and other structured laser beams.

3.
Opt Express ; 31(20): 32752-32760, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859070

RESUMO

The nonlinear propagation dynamics of vortex femtosecond laser pulses in optical media is a topic with significant importance in various fields, such as nonlinear optics, micromachining, light bullet generation, vortex air lasing, air waveguide and supercontinuum generation. However, how to distinguish the various regimes of nonlinear propagation of vortex femtosecond pulses remains challenging. This study presents a simple method for distinguishing the regimes of nonlinear propagation of femtosecond pulses in fused silica by evaluating the broadening of the laser spectrum as the input pulse power gradually increases. The linear, self-focusing and mature filamentation regimes for Gaussian and vortex femtosecond pulses in fused silica are distinguished. The critical powers for self-focusing and mature filamentation of both types of laser pulses are obtained. Our work provides a rapid and convenient method for distinguishing different regimes of nonlinear propagation and determining the critical powers for self-focusing and mature filamentation of Gaussian and structured laser pulses in optical media.

4.
Opt Express ; 30(10): 16987-16995, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221531

RESUMO

The filamentation of the femtosecond laser pulse in air with a preformed density hole is studied numerically. The result shows that density-hole-induced defocusing effect can relieve the self-focusing of the pulse, and by changing the length of the density hole and relative delay time, the filamentation length, intensity, spectral energy density and broaden region can be effectively controlled. When a short density hole with millisecond delay time is introduced, a significant elongation of the filamentation and enhancement of supercontinuum intensity can be obtained. This study provides a new method to control filamentation by pulse sequence.

5.
Opt Express ; 30(25): 44886-44895, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522902

RESUMO

Filamentation of intense femtosecond laser pulses in optical media has attracted great attention due to its various unique characteristics and potential applications. It is an important task to determine the critical power for the filamentation especially in many applications, which can be obtained by evaluating the transmitted pulse energy through a pinhole located in the filamentation region as a function of input laser energy. The pinhole diameter is very crucial to the measurement. However, there is no report on the experimental determination of critical power for filamentation in air by using the pinhole method and the influence of the pinhole diameter on the determination. In this paper, we numerically and experimentally investigate the influence of pinhole diameter on the determination of the filamentation critical power. The obtained critical power tends to a reasonable value as the decrease of the pinhole diameter, because the transmitted energy through the pinhole with a smaller diameter is more sensitive to the change of energy distribution in the beam cross section during the beginning process of filamentation. Under our experimental condition, the pinhole diameter as small as ∼50 µm is applicable to be used to determine the critical power for filamentation of femtosecond laser pulses in air.

6.
Opt Express ; 30(10): 17567-17576, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-36221576

RESUMO

Intense vector supercontinuum (SC) radiation with spatial polarization is obtained by using 800nm femtosecond vector laser beams in the air. The SC generated by azimuthally, radially, cylindrically polarized beams, and higher-order vector beams are investigated, respectively. The results show that the SC generated by vector beams is greatly enhanced compared to that by a Gaussian beam. The energy density of SC radiation reaches the order of 1µJ/nm in a bandwidth of 258 nm from 559 nm to 817 nm and 0.1 µJ/nm from 500 nm to 559 nm. Furthermore, by checking the polarization distribution of SC in different wavelengths from visible to near-infrared bands, we find that the SC maintains nearly the same polarization distribution as pump pulses. This work provides an effective and convenient way to generate powerful SC vector beams which may facilitate potential applications including optical communication, micro/nano-fabrication, and super-resolution microscopy.

7.
Opt Express ; 25(20): 23910-23919, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-29041341

RESUMO

One- and two-dimensional filament arrays are obtained in fused silica by using two and three interfered femtosecond laser beams, respectively. By modulating the number, cross angle, and azimuth of the beams, the dimension, period, orientation, and geometry of the filament-array can be controlled. The multiple beams interference method provides a convenient and effective method to generate and control the filament array in optical media with multiple degrees of freedom but without any external pulse modulation or focal element.

8.
Sci Rep ; 14(1): 5824, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461366

RESUMO

We perform numerical simulations to investigate the nonlinear propagation dynamics of femtosecond Gaussian and vortex beams in fused silica. By analyzing the extent of spectral broadening, we are able to distinguish between the linear, self-focusing, and filamentation regimes. Additionally, the maximum intensity and fluence distribution within the cross-section of the vortex beams are analyzed for different incident laser energies. The results demonstrate a direct correlation between the spectral broadening and the peak intensity of the femtosecond laser pulse. As a result, this provides a theoretical foundation for distinguishing different propagation regimes, and determining critical powers for self-focusing and filamentation of both femtosecond Gaussian and structured beams.

9.
Bioact Mater ; 36: 112-125, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38440324

RESUMO

Androgenic alopecia (AGA) is a highly prevalent form of non-scarring alopecia but lacks effective treatments. Stem cell exosomes have similar repair effects to stem cells, suffer from the drawbacks of high cost and low yield yet. Cell-derived nanovesicles acquired through mechanical extrusion exhibit favorable biomimetic properties similar to exosomes, enabling them to efficiently encapsulate substantial quantities of therapeutic proteins. In this study, we observed that JAM-A, an adhesion protein, resulted in a significantly increased the adhesion and resilience of dermal papilla cells to form snap structures against damage caused by dihydrotestosterone and macrophages, thereby facilitating the process of hair regrowth in cases of AGA. Consequently, adipose-derived stem cells were modified to overexpress JAM-A to produce engineered JAM-A overexpressing nanovesicles (JAM-AOE@NV). The incorporation of JAM-AOE@NV into a thermosensitive hydrogel matrix (JAM-AOE@NV Gel) to effectively addresses the limitations associated with the short half-life of JAM-AOE@NV, and resulted in the achievement of a sustained-release profile for JAM-AOE@NV. The physicochemical characteristics of the JAM-AOE@NV Gel were analyzed and assessed for its efficacy in promoting hair regrowth in vivo and vitro. The JAM-AOE@NV Gel, thus, presents a novel therapeutic approach and theoretical framework for promoting the treatment of low cell adhesion diseases similar to AGA.

10.
J Cosmet Dermatol ; 21(12): 6893-6901, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36047672

RESUMO

OBJECTIVES: Patients with multiple pregnancies, multiple pregnancies, and a history of severe obesity, the abdominal wall muscles, and skin exhibit rectus abdominis separation and skin laxity due to prolonged overstretching, which causes damage to both the patient's appearance and health. Abdominoplasty is a surgical solution to the problems of separation of the rectus abdominis muscle and laxity of the skin of the abdominal wall under direct vision, which is important for patients with the above problems. Currently, many studies have been reported on abdominoplasty, however, no reverent bibliometric analyses of abdominoplasty have been published. METHODS: In this study, we screened 1,119 studies on abdominoplasty between 2011 and 2021 based on the Web of Science Core Collection (WOSCC) database and performed a bibliometric analysis. RESULTS: We found that high-quality research related to abdominoplasty has increased in the last decade, and the United States was the leading country in the field of abdominoplasty. Stanford university ranked first in number of publications and citations. Aesthetic surgery journal was the most productive journal, followed by the Plastic and reconstructive surgery and Aesthetic plastic surgery. In addition, bariatric surgery, venous thromboembolism, rectus diastasis, breast reconstruction and umbilicoplasty are the keywords of recent publications that are the focus of current research. CONCLUSION: This study provides a comprehensive analysis and visualization of global research trends on abdominoplasty from 2011 to 2021, and improvements in abdominoplasty to reduce the incidence of postoperative complications will remain a focus of future research.


Assuntos
Parede Abdominal , Abdominoplastia , Procedimentos de Cirurgia Plástica , Gravidez , Feminino , Humanos , Abdominoplastia/efeitos adversos , Parede Abdominal/cirurgia , Reto do Abdome/cirurgia , Complicações Pós-Operatórias
11.
J Cosmet Dermatol ; 21(8): 3486-3493, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34928541

RESUMO

OBJECTIVE: We aimed to explore a novel method for ear reconstruction stent remodeling to achieve high patient satisfactory outcomes. METHODS: This study is a retrospective review of patients with congenital or acquired ear defects who were prepared for one-stage ear reconstruction with high-density porous polyethylene stent between May 2020 and May 2021. A standardized data collection template was used to collect related variables. In this study, the detailed reconstruction surgery process is carefully described, and the postoperative healing process of the ear reconstruction was closely observed. RESULTS: A total of 26 patients for one-stage ear reconstruction with high-density porous polyethylene stent or autogenous costal cartilage scaffolds were admitted to the department of plastic surgery in our hospital between May 2020 and May 2021. All patients were followed until their ear flaps were alive and details of the ear shape were revealed. The patients with new remolding method were no severe complications and only a patient had stent exposure, and were highly satisfied with both appearance and function. CONCLUSIONS: The application of novel remodeling method is a promising way for ear reconstruction stent shaping with little postoperative complication and excellent postoperative patient satisfaction.


Assuntos
Microtia Congênita , Procedimentos de Cirurgia Plástica , Microtia Congênita/cirurgia , Orelha Externa , Humanos , Polietileno , Porosidade , Procedimentos de Cirurgia Plástica/efeitos adversos , Procedimentos de Cirurgia Plástica/métodos , Stents
12.
Toxicol Res (Camb) ; 11(2): 348-360, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35510230

RESUMO

Radioresistance is one of the key obstacles that may lead to the failure of cancer treatment. The underlying mechanisms of radioresistance remain largely unknown; however, increasing evidence has shown that long noncoding RNAs (lncRNAs) are involved in radiotherapy resistance of several cancers. In the present study, we demonstrated that radiation-elevated transcript (RET), a newly identified lnRNA, was highly expressed in cancer cells. Knockdown of RET significantly inhibited the proliferation and colony formation of cancer cells and markedly inhibited apoptosis. Furthermore, downregulation of RET in cancer cells significantly inhibited cell growth, decreased colony survival fractions, and promoted apoptosis in response to radiation treatment, indicating a role in radiation resistance. Moreover, RET knockdown significantly increased the expression of γ-H2AX, an indicator of DNA double strand damage, and reversed radiation-induced EMT, both of which contributed to its radiation resistance. In addition, a negative correlation was found between the expression of RET and PTEN. Rescue assays confirmed RET knockdown enhanced radiosensitivity of cancer cells by upregulating the expression of PTEN. Mechanistically, RET positively regulated Slug, a repressor of PTEN transcription, by acting as a molecular sponge of miR-3179. Our present study showed that RET conferred radioresistance by regulating miR-3179/Slug/PTEN axis, indicating that RET may be a potential target for the clinical application in cancer patients with radioresistance.

13.
Psychol Res Behav Manag ; 14: 393-403, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33859505

RESUMO

The incidence of neurodevelopmental disorders especially in children has been on the rise in recent decades, which is possibly caused by many different factors. In order to further explain this situation and arouse enough attention, this review will specifically elaborate genetic aspects and pathogenic hypothesis of these two kinds of neurodevelopmental diseases in children, autism and attention deficit hyperactivity disorder (ADHD) while analyzing the relationship between different environmental toxins and these two disorders. The effects of these pathogenic factors such as heavy metal lead, mercury, polyvinyl chloride (PVC) and polychlorinated biphenyls (PCBs) and their strong pathogenicity will be explained in detail through literature data retrieval and analysis. In addition, other neurotransmitter such as norepinephrine (NE) and serotonin (5-HT) signaling factors coming down to these two neurodevelopmental disorders and how their abnormal concentration present in the blood as well as the completely opposite results among experimental groups and control group will be elaborated. Furthermore, other high-risk and high-exposure factors may contribute to both diseases, such as alcohol and smoking abuse among parents, air pollutants PM2.5 and PM10 in the environment will also be discussed in the review. Since these environmental toxins and other harmful substances discussed in the paper have been linked to an increasing number of children with autism and ADHD in recent decades, from the medical perspective, this review will put forward certain succinct points to the aspects of minimizing relevant exposure or risks in clinical and daily life, as well as feasible suggestions in public health area for children, parents and prospective parents, to curb the growth of these two diseases in part by raising awareness in the population and reducing unnecessary exposure.

14.
Opt Express ; 18(25): 26007-17, 2010 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21164948

RESUMO

The propagation of tightly focused femtosecond laser pulse with numerical aperture of 0.12 in air is investigated experimentally. The formation and evolution of the filament bunch are recorded by time-resolved shadowgraph with laser energy from 2.4 mJ to 47 mJ. The distribution of electron density in breakdown area is retrieved using Nomarski interferometer. It is found that intensity clamping during filamentation effect still play a role even under strong external focusing. The electron density in some interaction zones is higher than 3 × 10(19) cm(-3), which indicates that each air molecule there is ionized.


Assuntos
Lasers , Ar , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
15.
Opt Lett ; 35(7): 974-6, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20364188

RESUMO

The third-harmonic (TH) emission characteristics from femtosecond laser filament, the center of which is screened by a thin metallic fiber, are experimentally investigated. The intensity of the TH emission has been enhanced for 1 order of magnitude by comparing with the undisturbed filament. The physical mechanism of the TH enhancement is analyzed to be the diffraction of the TH emission on the fiber and a redistribution of laser energy during the reconstruction of the two-colored filament. These two factors can release a part of the TH energy from the filament core into the background and keep more TH energy after the termination of filament.

16.
Opt Express ; 16(12): 8332-41, 2008 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-18545547

RESUMO

The influence of air turbulence on the long-range filamentation of femtosecond laser pulses has been numerically investigated. Simulations are performed for different parameters of air turbulence and laser pulses. Simulation results indicate that the diameter of filaments formed by free propagated fs laser pulse can be widened to mm level under air turbulence. However, the widening effect can be suppressed if the propagating distance before the on-set position of filamentation becomes shorter. The reduction of non-linear focal length can be realized by pre-focusing of the laser pulse or increasing of the laser intensity. The effect of the inner scale of air turbulence on the filamentation has also been studied.


Assuntos
Ar , Lasers , Modelos Teóricos , Refratometria/métodos , Processamento de Sinais Assistido por Computador , Simulação por Computador , Luz , Dinâmica não Linear , Espalhamento de Radiação
17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 78(5 Pt 2): 055401, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19113181

RESUMO

The characteristics of filaments formed by femtosecond-laser pulses freely propagating in air are different from those of filaments generated with a focal lens. A scheme combining (2D+1) modeling of the nonlinear Schrödinger equation and ray-tracing method is proposed to provide a fast estimate of the long-range filamentation process in a single-filament regime. A filament with a length of more than 100m is formed by a 10-mJ , negative chirped 350-fs laser pulse freely propagating in air. A ray-tracing calculation based on the refractive index field obtained from the nonlinear Schrödinger simulation shows that, in the 100-m propagation range, the main mechanism of filamentation is the spatiotemporal moving focus induced by the initial distribution of the laser intensity. The analysis of ray trajectories suggests that the energy exchange between background and filament core due to refocusing of light rays can be induced by Kerr self-focusing without the help of the ionization effect. The plasma defocusing can be observed only at a very short distance on the propagation track, and it prevents the collapse of the laser field.

18.
Brain Res Bull ; 142: 176-182, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30016728

RESUMO

OBJECTIVE: To investigate the prognostic value of aspirin reaction units (ARU) in a 3-month follow-up study in a cohort of Chinese patients with first-ever ischemic stroke. METHODS: Prospective single-center survey of acute ischemic stroke patients receiving aspirin therapy. Two hundred and seventy-five Chinese patients with first-ever ischemic stroke who previously received aspirin therapy were enrolled. ARU was measured using the VerifyNow system. A cutoff of 550 ARU was used to determine the presence of aspirin resistance (AR). RESULTS: Median age at study entry was 67 years (IQR: 59-75) and 142(51.6%) were male. A total of 52 of 275 enrolled patients (18.9%) were AR. Median regression estimated a statistically significant increase in NIHSS score of 0.033 point for every 1-point increase in ARU (95% CI, 0.024 to 0.068; P < 0.001). The unfavorable outcomes distribution across the ARU quartiles ranged between 11.8% (first quartile) to 64.8% (fourth quartile). After adjusting for other established risk factors, in multivariate models comparing the third and fourth quartiles against the first quartile of the ARU, levels of ARU were associated with unfavorable outcome, and the adjusted risk of unfavorable outcome increased by 145% (OR = 2.45 [95% CI 1.46-3.87], P = 0.011) and 317% (4.17[2.76-6.15], P < 0.001), respectively. Similarly, the adjusted risk of mortality increased by 215% (OR = 3.15 [95% CI 1.98-4.73], P = 0.008) and 429% (5.29[4.02-8.17], P < 0.001), respectively. CONCLUSIONS: The results suggest that AR is a meaningful and independent marker to predict short-term functional outcome in patients with ischemic stroke.


Assuntos
Aspirina/uso terapêutico , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Isquemia Encefálica/epidemiologia , Resistência a Medicamentos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/epidemiologia
19.
Opt Express ; 15(24): 16102-9, 2007 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-19550899

RESUMO

The robustness and prolongation of multiple filamentation (MF) for femtosecond laser propagation in air are investigated experimentally and numerically. It is shown that the number, pattern, propagation distance, and spatial stability of MF can be controlled by a variable-aperture on-axis pinhole. The random MF pattern can be optimized to a deterministic pattern. In our numerical simulations, we configured double filaments to principlly simulate the experimental MF interactions. It is experimentally and numerically demonstrated that the pinhole can reduce the modulational instability of MF and is favorable for a more stable MF evolution.

20.
Opt Express ; 14(2): 773-8, 2006 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-19503396

RESUMO

The spatial evolution of plasma filaments in air induced by femtosecond laser pulses is investigated experimentally. Several major filaments and small scaled additional filaments are detected in the plasma channel. The complicated interaction process of filaments as splitting, fusion and spreading is observed. The major filaments propagate stably, and the small scaled additional filaments can be attracted to the major filaments and merged with them. The major filaments are formed due to the perturbation of initial beam profile and the small scaled filaments are mainly caused by the transverse modulational instability.

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