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1.
ACS Nano ; 18(27): 17672-17680, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38920321

RESUMO

Layer-engineered interlayer excitons from heterostructures of transition-metal dichalcogenides (TMDCs) exhibit a rich variety of emissive states and intriguing valley spin-selection rules, the effective modulation of which is crucial for excitonic physics and related device applications. Strain or high pressure provides the possibility to tune the energy of the interlayer excitons; however, the reported emission intensity is substantially quenched, which greatly limits their practical application in optoelectronic devices. Here, via applying uniaxial strain based on polyvinyl alcohol (PVA) encapsulation technique, we report enhanced layer-engineered interlayer exciton emission intensity with largely modulated emission energy in WSe2/WS2 heterobilayer and heterotrilayer. Both momentum-direct and momentum-indirect interlayer excitons were observed, and their emission energies show an opposite shift tendency upon applied strain, which agrees with our DFT calculations. We further demonstrate that intralayer and interlayer exciton states with low phonon interactions can be modulated through the mechanical strain applied to the PVA substrate at low temperatures. Due to strain-induced breaking of the 3-fold rotational symmetry, we observe the enhanced valley polarization of interlayer excitons. Our study contributes to the understanding and modulation of the optical properties of interlayer excitons, which could be exploited for optoelectronic device applications.

2.
Ther Adv Respir Dis ; 18: 17534666231221771, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38235607

RESUMO

BACKGROUND: With the rise of targeted treatments for asthma, treatment with omalizumab is a new option. OBJECTIVES: To assess the improvement of pulmonary function with additional omalizumab treatment in patients (⩾6 years old) with moderate-to-severe allergic asthma. DATA SOURCES AND METHODS: Observational studies of randomized controlled trials of add-on omalizumab for the treatment of patients with moderate-to-severe allergic asthma, published from the establishment till August 2022, were retrieved from WAN FANG DATA, PubMed, CNKI, Embase, Cochrane, and Web of Science databases. Data extraction and quality evaluation were performed on the literature that met the inclusion criteria, using RevMan 5.3 to analyze the data. RESULTS: A total of 11 randomized controlled clinical trials were included, involving a total of 3578 patients with asthma, 1856 patients in the omalizumab group, and 1722 patients in the control group. The improvement in Forced expiratory volume in 1 s as a percentage of predicted normal and Forced expiratory volume in 1 s was more pronounced in the omalizumab-treated group [MD = 3.91, 95% confidence interval (CI): 1.89-5.94, p = 0.0002; MD = 0.09, 95% CI: 0.05-0.13, p < 0.0001], while the improvement in Morning Peak expiratory flow rate was not statistically different between the two groups (MD = 3.64, 95% CI: -22.17-29.45, p = 0.78). CONCLUSION: Additional omalizumab treatment showed some improvement in lung function in patients with moderate-to-severe asthma. TRIAL REGISTRATION: PROSPERO ID:CRD42022378498.


Improvement of lung function in asthmatic patients with additional omalizumabIn this paper, by screening clinical trials related to the treatment of patients with moderate and severe asthma with omalizumab plus, we extracted indicators related to lung function for meta-analysis and found that in patients with moderate to severe asthma, the addition of omalizumab can improve lung function to a certain extent and delay the worsening of lung function.


Assuntos
Antiasmáticos , Asma , Omalizumab , Humanos , Antiasmáticos/uso terapêutico , Asma/diagnóstico , Asma/tratamento farmacológico , Volume Expiratório Forçado , Pulmão , Omalizumab/uso terapêutico , Resultado do Tratamento
3.
Cell Signal ; 115: 111016, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38128708

RESUMO

Tumor immunosuppression are prominent characteristics of brain glioma. Current standard modality including surgical resection and chemoradiotherapy do not significantly improve clinical outcomes. Cancer-associated fibroblasts (CAFs) that regard as important stromal cells in tumor microenvironment have been confirmed to play crucial roles in tumor development. However, the effects of CAFs on tumor immunosuppression in glioma are not well expounded. In this study, we report that CAFs contributes to the formation of glioma immunosuppressive microenvironment. Specifically, we found that glioma-derived Jagged1 enhanced the proliferation and PD-L1 expression of CAFs in vitro. Importantly, we discovered that Notch1, c-Myc and PD-L1 expression were significantly increased in high Jagged1-expressing gliomas, moreover, we further confirmed that Notch1 and PD-L1 expression located on the CAFs in glioma tissues. We also found that glioma-derived Jagged1 promotes the increase of tumor-infiltrating macrophages, M2 macrophages and Foxp3 Treg cells, as well as no significance of M1 macrophages and CD8+ T cells, indicating potential immunosuppression. This study opens up novel therapeutic strategies reversing CAF immunosuppression for gliomas.


Assuntos
Fibroblastos Associados a Câncer , Glioma , Proteína Jagged-1 , Humanos , Antígeno B7-H1/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Glioma/metabolismo , Microambiente Tumoral , Proteína Jagged-1/metabolismo
4.
Opt Lett ; 47(15): 3800-3803, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35913318

RESUMO

We investigate the impact of Raman scattering on pure quartic solitons (PQSs) in an optical fiber with quartic dispersion. An analytical expression of the Raman-induced frequency shift (RIFS) of a PQS is obtained by using the variational approach with the Gaussian function ansatz. We find the RIFS of a PQS is inversely proportional to the sixth power of pulse width, when the fiber is short enough. The RIFS of a PQS is more sensitive to the pulse width, compared with that of a conventional soliton which is inversely proportional to the fourth power of pulse width. The theoretical predictions show good agreement with numerical results. In addition, we also discuss the RIFS of the other three typical pulses with the same peak power and pulse width as the PQS. These results provide a thorough understanding of the role of higher-order nonlinear effects on the propagation dynamics of PQSs.

5.
Biomed Chromatogr ; 35(11): e5187, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34061396

RESUMO

Burdock root is the root of Arctium lappa L., a plant of the Compositae family, which has the effects of dispersing wind and heat, detoxifying and reducing swelling. In order to better control the quality of burdock root, a screening study of quality control indicators was carried out. The current research combines biological activity evaluation with chemical analysis to screen and identify the biologically active compounds of burdock root as chemical components for the quality control of herbal medicine. The efficacy of 10 batches of ethanol extracts of burdock roots was evaluated by a tumor inhibition experiment in S180 tumor-bearing mice. The five main chemical components of these extracts were simultaneously quantitatively measured by ultra-high performance liquid chromatography combined with triple quadrupole mass spectrometry. Pearson correlation analysis was used to establish the relationship between these extracts' biological activity and chemical properties. The results showed that chlorogenic acid, caffeic acid and cynarin were positively correlated with the effect of inhibiting tumor growth, and further bioassays confirmed this conclusion. In conclusion, chlorogenic acid, caffeic acid and cynarin can be used as quality control markers for burdock root's antitumor effect.


Assuntos
Antineoplásicos Fitogênicos , Arctium/química , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais , Espectrometria de Massas em Tandem/métodos , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Limite de Detecção , Modelos Lineares , Camundongos , Neoplasias Experimentais/patologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/normas , Raízes de Plantas/química , Reprodutibilidade dos Testes
6.
Saudi J Biol Sci ; 25(2): 248-252, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29472773

RESUMO

Twelve representative buffalo were selected from 22 suckling calves, 41 weaned calves, 57 reserve bulls and 20 adult bulls for slaughter. The study aims to assess the effect of age on dressing percentage, meat percentage and carcass meat yield and physico-chemical properties of longissimus dorsi and biceps femoris, and to evaluate the correlation between live weight and marbling, backfat thickness, rib eye area. The results showed that the slaughter performance and meat quality of Binlangjang male buffalo showed an obvious change with age. The dressing percentage decreased from 54.93% to 51.22% with the increase of age, while meat percentage and carcass meat yield increased gradually with age, which were 34.58-38.59%, 62.95-75.34%; Marbling, backfat thickness and rib eye area increased with age, and there was significant difference between the situation before 3 months and after 12 months of age (P < 0.05). The moisture content was maximum at birth, which then gradually decreased, but the difference was insignificant (P > 0.05). The levels of fat, protein, cholesterol and inosine acid were significantly different before 3 months of age from those after 12 months (P < 0.05). Cholesterol content was negatively correlated with age, the minimum was 80.25 mg/100 g; Inosine acid content increased with age, reaching 133.11 mg/100 g. Marbling, backfat thickness, rib eye area had a high correlation with live weight, with correlation coefficients respectively at 0.9096, 0.9291, 0.9551. Based on the prediction model of live weight, Buffaloes was suitable for slaughtering for superior slaughter performance and meat quality after 24 months of age.

7.
Sci Rep ; 7(1): 122, 2017 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-28273924

RESUMO

The approximate analytical expressions of tripole-mode and quadrupole-mode solitons in (1 + 1)-dimensional nematic liquid crystals are obtained by applying the variational approach. It is found that the soliton powers for the two types of solitons are not equal with the same parameters, which is much different from their counterparts in the Snyder-Mitchell model (an ideal and typical strongly nolocal nonlinear model). The numerical simulations show that for the strongly nonlocal case, by expanding the response function to the second order, the approximate soliton solutions are in good agreement with the numerical results. Furthermore, by expanding the respond function to the higher orders, the accuracy and the validity range of the approximate soliton solutions increase. If the response function is expanded to the tenth order, the approximate solutions are still valid for the general nonlocal case.

8.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 31(2): 235-239, 2017 02 15.
Artigo em Chinês | MEDLINE | ID: mdl-29786260

RESUMO

Objective: To determine the efficacy of D980-nm laser in dissolving fat and renewing skin, and to explore the clinical application of D980-nm laser in reconstruction of photodamaged skin. Methods: Eighteen 12-14 month-old male Sprague-Dawley rats, weighing 400-450 g, were randomly divided into 3 groups ( n=6). The rat skin at the left side was exposed to D980-nm laser irradiation at a density of 20 J/cm 2, a power of 8 W, a pulse width of 20 ms, and a pulse frequency of 40 Hz for 1 time (group A), 2 times of 5-minute interval (group B), and 3 times of 5-minute interval (group C) as a treatment course, for 4 treatment courses with an interval of 1 week; the other side of the skin was not treated as the control groups (groups A1, B1, and C1, respectively). After 8 weeks, the skin was harvested for HE staining and immunohistochemical staining to observe the structure changes of skin, to measure the dermal thickness, to count the number of fibroblasts, and detect the expressions of transforming growth factor ß 1 (TGF-ß 1) and basic fibroblast growth factor (bFGF). Results: Compared with groups A1, B1, and C1, the skin structure was significantly improved in groups A, B, and C. After D980-nm laser irradiation, the number of fat cells decreased; local angiogenesis was observed; the total number of fibroblasts and fibers increased; the collagen fiber had large diameter, and arranged closely and regularly; the dermal thickness and the number of the fibroblasts increased; and the expressions of TGF-ß 1 and bFGF were significantly enhanced, showing significant differences ( P<0.05). With increased D980-nm laser irradiation times, the above indexes increased, showing significant differences between group C and groups A, B ( P<0.05). Conclusion: D980-nm laser treatment has lipolytic and tender effect on the skin, and the frequency of the treatment is an important factor in skin renewal.


Assuntos
Fibroblastos/metabolismo , Terapia a Laser , Tecido Adiposo , Animais , Fator 2 de Crescimento de Fibroblastos/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Pele , Fator de Crescimento Transformador beta1/metabolismo
9.
Zhong Xi Yi Jie He Xue Bao ; 10(8): 918-24, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22883409

RESUMO

OBJECTIVE: To establish a rat model of ulcerative colitis with syndrome of spleen deficiency and dampness stagnancy. METHODS: Sixty rats were divided into normal control group, ulcerative colitis group, ulcerative colitis with syndrome of spleen deficiency and dampness stagnancy group (model group) and strengthening spleen for resolving dampness group. Ulcerative colitis in rats was induced by enema containing trinitrobenzene sulfonic acid (TNBS) and ethanol. The rats in the model group were suffered from standing in water, limiting sleeping time and abnormal diet based on administration of TNBS and ethanol. The rats in the spleen strengthening and dampness resolving group were gastrically administered with Shenlin Baizhu Powder, a compound traditional Chinese herbal medicine. Symptoms, signs and pathological changes in colon tissue of rats were observed after modeling. The levels of interleukin (IL)-6, IL-8 and tumor necrosis factor-α (TNF-α) in serum of rats were measured by enzyme-linked immunosorbent assay. RESULTS: The rats in the model group showed lethargy, poor appetite, loss of energy, diarrhea and bloody stool. Their body weight decreased significantly compared with the normal control group, and similar changes were found in the comparison of food intake, drinking amount, urine amount, stool wet weight and assay of spontaneous activity (P<0.05). When observed under a light microscope, the colon tissues of rats in the model group showed mucosal edema, congestion, inflammatory cell infiltration and ulceration. The degree of colon injury and IL-6, IL-8 and TNF-α levels were significantly increased (P<0.05) as compared to those in the normal control group. The changes mentioned above were improved by Shenlin Baizhu Powder (P<0.05). CONCLUSION: The rat model of ulcerative colitis with syndrome of spleen deficiency and dampness stagnancy is successfully induced and has the characteristics of ulcerative colitis of humans both in pathological changes and in syndrome.


Assuntos
Colite Ulcerativa , Modelos Animais de Doenças , Medicina Tradicional Chinesa , Animais , Colite Ulcerativa/patologia , Feminino , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
10.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 30(2): 182-7, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20462049

RESUMO

OBJECTIVE: To investigate the effects of drug-contained sera (DCS) of Naoluo Xintong (NLXT) and Zuogui Pill (ZGP) on the proliferation and differentiation of in vitro cultured embryonic neural stem cells (NSCs) in rats. METHODS: Rat's embryonic NSCs were cultured in medium supplemented with 10% DCS with NLXT and ZGP separately, the effects of DCS in enhancing proliferation and inducing differentiation were observed and compared by phase contrast microscopy and immunofluorescence staining. RESULTS: Majority of NSCs were induced to neurons, astrocytes or oligodendrocytes in medium supplemented with either DCS-NLXT or DCS-ZGP, with the growth of them promoted to some extent. However, DCS-NLXT induced the differentiation rather slowly but with the differentiated neurons more resemble to the mature neuron in morphology, while DCS-ZGP promoted the stem cell growth more effectively. CONCLUSION: Both NLXT and ZGP could promote the differentiation and growth of in vitro cultured NSCs, but with exiguous difference. It is feasible to induce the proliferation and differentiation of NSCs by way of using Chinese medicine drug-therapy for supplementing qi and activating blood circulation as well as that for tonifying Shen to generate marrow.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Soro/química , Animais , Células Cultivadas , Feminino , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Ratos Wistar
11.
J Am Chem Soc ; 132(16): 5572-3, 2010 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-20364814

RESUMO

A new tetragonal phase of PbTiO(3) was discovered, in which each TiO(6) octahedron pair shares an edge and stacks over following pairs in an interlaced manner to form a one-dimensional (1D) columned structure along the c-axis. This new tetragonal phase of PbTiO(3) transforms into a normal perovskite phase in air at elevated temperature.

12.
Appl Opt ; 47(30): 5668-81, 2008 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-18936816

RESUMO

We present a theoretical investigation on the formation of hot images in an intense laser beam through cascaded Kerr medium disks, to disclose the distribution and intensity of hot images in high-power disk amplifiers. It is shown that multiple hot images from an obscuration may be formed, instead of one hot image as reported previously in the literature. This gives a clear explanation for the curious damage pattern of hot images, namely, damage sites appearing on alternating optics in periodic trains. Further analysis demonstrates that the distribution and intensity of hot images depend closely on the number of Kerr medium disks, the distance from the obscuration to the front of the first disk downstream, the space between two neighboring disks, and the thickness and B integral of each disk. Moreover, we take two cascaded Kerr medium disks for example to detail multiple hot images from an obscuration and confirm the theoretical results by numerical simulations.

13.
Appl Opt ; 47(8): 1152-63, 2008 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-18327289

RESUMO

We present a study of the formation of a hot image in an intense laser beam through a slab of Kerr medium with gain and loss, beyond the thin-medium approximation, to especially disclose the dependence of the hot image on the size of obscuration. Based on the angular spectrum description of light propagation and the mean-field approximation we obtain the expression for intensity of the hot image, which clearly shows the dependence of intensity of the hot image on the size of obscuration. It is shown that, as the size of obscuration increases, the intensity of the corresponding hot image first increases gradually, after reaching a maximum value, it decreases rapidly to a minimum value, meaning that there exists an optimum size of obscuration, which leads to the most intense hot image. Further analysis demonstrates that the optimum size of obscuration is approximately determined by the effective fastest growing spatial frequency for a given case. For the output light beam of a given intensity, with the gain coefficient of the Kerr medium slab increasing, or the loss coefficient decreasing, the optimum size of obscuration becomes bigger, while the hot image from the obscuration of a given size becomes weaker, suggesting that high gain and low loss can efficiently suppress the hot image from obscurations. The theoretical predictions are confirmed by numerical simulations.

14.
Diagn Microbiol Infect Dis ; 58(4): 469-75, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17509797

RESUMO

Shigella sonnei replaced Shigella flexneri to become the predominant species for shigellosis in 2001 to 2003 in central Taiwan. A total of 425 S. sonnei isolates collected from 1996 to 2004 were available for characterization by pulsed-field gel electrophoresis (PFGE), inter-IS1 spacer typing (IST), and antimicrobial susceptibility testing. The results showed that at least 21 IST clones had emerged for the S. sonnei infections in 1996 to 2004. Most IST clones lasted for a short time; some circulated for 2 to 3 years. An IST1 clone, detected for the first time in 2000, was the most prevalent and responsible for the shigellosis epidemic in 2001 to 2003. Over 3 years of sustained transmission, the IST1 clone evolved into many strains with different PFGE genotypes and antibiograms. The ancestor, with a J16N09.0019 PFGE genotype, remained to be the predominant circulating strain in the period studied; however, new strains with certain PFGE genotypes and antibiograms could become major circulating strains for subsequent infections.


Assuntos
Disenteria Bacilar/epidemiologia , Disenteria Bacilar/microbiologia , Evolução Molecular , Shigella sonnei/efeitos dos fármacos , Shigella sonnei/genética , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana , Análise por Conglomerados , Elementos de DNA Transponíveis/genética , DNA Bacteriano/genética , DNA Intergênico/genética , Eletroforese em Gel de Campo Pulsado , Humanos , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Polimorfismo de Fragmento de Restrição , Shigella sonnei/classificação , Shigella sonnei/isolamento & purificação , Taiwan/epidemiologia
15.
J Clin Microbiol ; 44(11): 3928-33, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16988023

RESUMO

Shigella sonnei contains numerous IS1 elements. The existence of polymorphisms in the length of the inter-IS1 spacer is a basis for the development of a PCR-based method for the subtyping of S. sonnei strains. The usefulness of inter-IS1 spacer typing (IST) was evaluated and compared with that of pulsed-field gel electrophoresis (PFGE) by characterization of S. sonnei isolates from epidemiologically nonrelated cases and outbreaks and of isolates that were indistinguishable by PFGE and that were collected from independent infection events. IST was less discriminatory than PFGE, with discriminatory indices of 0.96 and 0.63, respectively, but was able to compensate for the drawbacks of PFGE. PFGE exhibited a high level of discriminatory power for S. sonnei isolates; however, PFGE was also, at times, too discriminatory, which was a disadvantage in constructing the clonal relationships among strains circulating over a period of months or years. Furthermore, IST provided greater subtyping information for isolates indistinguishable by PFGE. The present study indicates that IST is more useful than PFGE for investigating the genetic relationships among S. sonnei strains circulating over a longer time span and also for discriminating certain strains which are indistinguishable by PFGE.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Elementos de DNA Transponíveis , Shigella sonnei/classificação , Eletroforese em Gel de Campo Pulsado , Genótipo , Shigella sonnei/genética
16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 73(3 Pt 2): 036617, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16605687

RESUMO

We investigate modulation instability (MI) in negative-index material (NIM) with a Kerr nonlinear polarization based on a derived (3+1)-dimensional nonlinear Schrödinger equation for ultrashort pulse propagation. By a standard linear stability analysis, we obtain the expression for instability gain, which unifies the temporal, spatial, and spatiotemporal MI. It is shown that negative refraction not only brings some new features to MI, but also makes MI possible in ordinary material in which it is otherwise impossible. For example, spatial MI can occur in the defocusing regime, while it only occurs in the focusing regime in ordinary material. Spatiotemporal MI can appear in NIM in the case of anomalous dispersion and defocusing nonlinearity, while it cannot appear in ordinary material in the same case. We believe that the difference between the MI in NIM and in ordinary material is due to the fact that negative refraction reverses the sign of the diffraction term, with the signs of dispersion and nonlinearity unchanged. The most notable property of MI in NIM is that it can be manipulated by engineering the self-steepening effect by choosing the size of split-ring resonator circuit elements. To sum up the MI in ordinary material and in NIM, MI may occur for all the combinations of dispersion and nonlinearity.

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