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1.
Sci Rep ; 13(1): 10267, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37355715

RESUMO

Digital holography provides access to quantitative measurement of the entire complex field, which is indispensable for the investigation of wave-matter interactions. The emerging iterative phase retrieval approach enables to solve the inverse imaging problem only from the given intensity measurements and physical constraints. However, enforcing imprecise constraints limits the reconstruction accuracy and convergence speed. Here, we propose an advanced iterative phase retrieval framework for single-shot in-line digital holography that incorporates adaptive constraints, which achieves optimized convergence behavior, high-fidelity and twin-image-free reconstruction. In conjunction with morphological operations which can extract the object structure while eliminating the irrelevant part such as artifacts and noise, adaptive constraints allow the support region to be accurately estimated and automatically updated at each iteration. Numerical reconstruction of complex-valued objects and the capability of noise immunity are investigated. The improved reconstruction performance of this approach is experimentally validated. Such flexible and versatile framework has promising applications in biomedicine, X-ray coherent diffractive imaging and wavefront sensing.


Assuntos
Holografia , Holografia/métodos , Artefatos
2.
Opt Express ; 31(10): 15940-15941, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157683

RESUMO

We have found an error in our work reported in [Opt. Express31(4), 6241 (2023)10.1364/OE.483433], which we correct in this erratum. The authors apologize for this error and emphasize that none of the results are affected by this error.

3.
Opt Express ; 31(4): 6241-6251, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823885

RESUMO

The circle Olver beams (COBs) generated by modulation on the basis of a new type of Olver beam are presented numerically and experimentally. The zeroth order COB is the circle Airy beam. We demonstrate auto-focusing of the COBs with both inward and outward accelerations, where the odd order COBs display auto-defocusing while the even order COBs (ECOBs) tend to focus more abruptly. We also explore the effect of the decay factor and the scaling factor on the beams' focusing properties, such as the initial energy distribution, the focusing position, the focusing intensity and the focusing depth, by using the parity mode. In addition, we verify the self-healing property of the COBs. Finally, we set up an experimental platform to implement particle capture and manipulation with the ECOBs. Our results offer practical applications for particle manipulation, laser processing, etc.

4.
Opt Express ; 30(7): 11331-11344, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35473080

RESUMO

Tornado waves (ToWs), which refer to a light that accelerates and twists over both the radial and the angular directions, have gained a great deal of interest since the concept was introduced by Brimis et al [Opt. Lett.45, 280 (2020)10.1364/OL.45.000280]. In this paper, we superimpose two pairs of ring swallowtail vortex beams (RSVBs) to generate ToWs and we call them tornado swallowtail waves (ToSWs). Each pair consists of RSVBs while carrying orbital angular momentum of opposite helicity and slightly different with the radius of the main ring of RSVBs. The waves spiral forward and reveal intensity maxima, exhibiting a tornado-like intensity profile during propagation. Meanwhile, the angular acceleration of the ToSWs is illustrated via tracing the angular position of the high-intensity main lobes. It is found that ToSWs present very high values of angular acceleration. Compared with typical tornado waves, ToSWs are more diverse and tunable, giving a new degree of freedom to tailor the propagation dynamics due to the flexibility of the swallowtail diffraction catastrophe. In addition, we confirm such waves experimentally and the results match well with the numerical ones. Also, we demonstrate the ability of optical manipulation of ToSWs for the first time in that they allow for particles not only to be trapped but also to be rotated. Finally, we analyze the poynting vectors and power exchange of ToSWs to demonstrate convincingly the physical mechanism.

5.
Opt Express ; 30(9): 14146-14160, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473165

RESUMO

The Talbot-like effect of symmetric Pearcey beams (SPBs) is presented numerically and experimentally in the free space. Owing to the Talbot-like effect, the SPBs have the property of periodic, multiple autofocusing and self-healing. Meanwhile, the focusing positions and focusing times of SPBs are controlled by the beam shift factor and the distribution factors. Furthermore, the beam shift factor can also affect the Talbot-like effect and the Talbot period. It is believed that the results can diversify the application of the Talbot effect.

6.
Appl Opt ; 61(8): 1906-1911, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35297880

RESUMO

In this paper, by phase-modulating an optical wavefront on circular symmetric Airy vortex beams, we present the circular symmetric Airy-like vortex beams propagating along predesigned parabolic trajectories. Our result shows that we can realize the propagation of an optical vortex with a closed ring lobe along an accelerating parabolic trajectory within a certain propagation distance by using this kind of phase-modulated circular symmetric Airy beam. The vortex that is superimposed on the beams is able to reproduce after being blocked. Additionally, a single twisted dark channel or multiple tornado dark channels with orbital angular momentum rotating along the predesigned parabolic trajectories can also be formed when we impose the off-axis optical vortex on this kind of beam, which has potential in applications of light capturing.

7.
Opt Express ; 30(2): 1762-1772, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209330

RESUMO

We introduce a new type of multiple and off-axis optical bottles (OBs) based on the chirped circular Pearcey Gaussian vortex beam. This kind of beam allows the generation of the OBs with a perfect bottle shape through coherent superposition. Also, we show that the number and the position of the OBs can be precisely and flexibly controlled. The experimental results agree well with our numerical simulations, and we observe stable trapping of the mesocarbon microbeads particles by the proposed bottle beam.

8.
Opt Express ; 30(4): 6193-6202, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35209560

RESUMO

We introduce controllable Laguerre Gaussian wave packets (LGWPs) with self-accelerating and self-focusing properties along their predesigned parabolic trajectory via phase modulation. Numerically and experimentally recorded intensity patterns of controllable LGWPs with topological charges are obtained, and it is obvious that they agree well with the theoretical model. Furthermore, spatiotemporally controllable LGWPs can propagate stably along predesigned trajectories for many Rayleigh lengths. This paper not only provides a theoretical propagation model for these multi-dimensional controllable LGWPs, but also promotes further development of the basic research into self-bending and autofocusing structured light fields.

9.
Opt Express ; 30(1): 232-242, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-35201202

RESUMO

A new type of Airy beam arisen from the modification of Fourier spectrum is introduced numerically and experimentally. The autofocusing Airy beam (AAB) exhibits the features of off-axis autofocusing and transverse self-accelerating, producing a needle-like focus in the longitudinal direction and a tiny focal spot at the focusing plane. Furthermore, the focusing properties such as focusing position, focal spot size, focusing intensity and depth of focus can be adjusted by modulating parameters of the AAB. Experimental demonstrations of particle trapping and manipulation with the AAB are also presented. The number of trapped particles can be controlled by changing the focal spot size at the autofocusing plane. Our results offer practical applications in particle manipulation, fluorescent imaging technology, laser spectroscopy and so on.

10.
Appl Opt ; 60(32): 10168-10175, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34807124

RESUMO

We introduce the propagation of Pearcey Gaussian (PG) beams in a strongly nonlocal nonlinear medium (SNNM) analytically. Our results show that PG beams propagating in the SNNM have two different focusing positions. The intensity peak appears at different focusing positions depending on the selection of the nonlinear parameters. In addition, the effects of the nonlinear parameters and the scaling factor on the trajectory, the position of the intensity focusing, the intensity evolution between focus locations, and the radiation force are studied.

11.
Appl Opt ; 60(23): 6730-6735, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613149

RESUMO

In this paper, the propagation properties of the odd-Pearcey Gaussian beam (OPGB) in a parabolic potential are investigated analytically and numerically. Except for the auto-focusing at the focal plane, the OPGB performs a weak off-axis focusing unexpectedly. The focusing distance and the focal intensity can be adjusted by choosing an appropriate parabolic parameter. Also, the Poynting vector of the OPGB is demonstrated. In addition, we investigate the radiation forces of the OPGB and find that the trapping points can be generated during propagation.

12.
Nature ; 521(7551): 222-6, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-25754330

RESUMO

Psoriasis is a chronic inflammatory skin disorder that affects approximately 2-3% of the population worldwide and has severe effects on patients' physical and psychological well-being. The discovery that psoriasis is an immune-mediated disease has led to more targeted, effective therapies; recent advances have focused on the interleukin (IL)-12/23p40 subunit shared by IL-12 and IL-23. Evidence suggests that specific inhibition of IL-23 would result in improvement in psoriasis. Here we evaluate tildrakizumab, a monoclonal antibody that targets the IL-23p19 subunit, in a three-part, randomized, placebo-controlled, sequential, rising multiple-dose phase I study in patients with moderate-to-severe psoriasis to provide clinical proof that specific targeting of IL-23p19 results in symptomatic improvement of disease severity in human subjects. A 75% reduction in the psoriasis area and severity index (PASI) score (PASI75) was achieved by all subjects in parts 1 and 3 (pooled) in the 3 and 10 mg kg(-1) groups by day 196. In part 2, 10 out of 15 subjects in the 3 mg kg(-1) group and 13 out of 14 subjects in the 10 mg kg(-1) group achieved a PASI75 by day 112. Tildrakizumab demonstrated important clinical improvement in moderate-to-severe psoriasis patients as demonstrated by improvements in PASI scores and histological samples.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Imunoterapia , Interleucina-23/antagonistas & inibidores , Terapia de Alvo Molecular , Psoríase/tratamento farmacológico , Adolescente , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Método Duplo-Cego , Epitélio/efeitos dos fármacos , Epitélio/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-23/química , Interleucina-23/imunologia , Pessoa de Meia-Idade , Subunidades Proteicas/antagonistas & inibidores , Subunidades Proteicas/química , Subunidades Proteicas/imunologia , Psoríase/imunologia , Psoríase/metabolismo , Psoríase/patologia , Pele/efeitos dos fármacos , Pele/imunologia , Pele/metabolismo , Pele/patologia , Resultado do Tratamento , Adulto Jovem
13.
Chest ; 144(6): 1795-1802, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24077095

RESUMO

BACKGROUND: The effects of mometasone furoate and fluticasone propionate on the hypothalamic-pituitary-adrenal axis were compared when administered from combination metered-dose inhaler (MDI) products. METHODS: In a randomized, open-label, placebo-controlled, parallel group study, 66 patients with mild to moderate asthma received one of the following four treatments bid through an MDI for 42 days: mometasone furoate/formoterol (MF/F) 200 µg/10 µg, MF/F 400 µg/10 µg, fluticasone propionate/salmeterol (FP/S) 460 µg/42 µg, or placebo. Plasma cortisol concentrations were measured over 24 h on days -1 (baseline) and 42. Geometric mean ratio (GMR) and 90% CI for mean change from baseline to day 42 in 24-h plasma cortisol area under the curve (AUC) were calculated for each treatment. If the 90% CI for the GMRs fell within 70% to 143%, treatments were deemed comparable. RESULTS: Mean baseline cortisol AUCs were similar across groups. Mean cortisol effects (change from baseline) were similar for MF/F 400 µg/10 µg and FP/S 460 µg/42 µg (GMR, 119%; 90% CI, 101%-140%). Effects of MF/F 200 µg/10 µg on cortisol AUC were similar to placebo (GMR, 92%; 90% CI, 78%-110%), whereas MF/F 400 µg/10 µg and FP/S 460 µg/42 µg lowered cortisol AUC vs placebo (GMR, 78% [90% CI, 66%-92%] and 66% [90% CI 56%-78%], respectively). All treatments were generally well tolerated. CONCLUSIONS: MF/F 400 µg/10 µg or FP/S 460 µg/42 µg bid through an MDI led to similar reductions from baseline in mean cortisol AUC (22% and 34% lower than placebo, respectively), whereas the effect of MF/F 200 µg/10 µg was similar to placebo.


Assuntos
Albuterol/análogos & derivados , Androstadienos/farmacologia , Asma/tratamento farmacológico , Etanolaminas/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Inaladores Dosimetrados , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Pregnadienodiois/farmacologia , Administração por Inalação , Adolescente , Adulto , Albuterol/administração & dosagem , Albuterol/farmacologia , Albuterol/uso terapêutico , Androstadienos/administração & dosagem , Androstadienos/uso terapêutico , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Asma/sangue , Broncodilatadores/administração & dosagem , Broncodilatadores/farmacologia , Broncodilatadores/uso terapêutico , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Quimioterapia Combinada , Etanolaminas/administração & dosagem , Etanolaminas/uso terapêutico , Feminino , Combinação Fluticasona-Salmeterol , Fumarato de Formoterol , Glucocorticoides/administração & dosagem , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Pessoa de Meia-Idade , Furoato de Mometasona , Sistema Hipófise-Suprarrenal/fisiologia , Pregnadienodiois/administração & dosagem , Pregnadienodiois/uso terapêutico , Resultado do Tratamento , Adulto Jovem
14.
Growth Factors ; 24(4): 268-78, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17381068

RESUMO

Chondrogenic promotion by rhGDF5 with or without rhTGFbeta3 was studied in pellet culture of human mesenchymal stem cells (HMSCs). A synergy between rhGDF5 and rhTGFbeta3 was observed in promoting chondrogenesis. rhBMP2, rhBMP6, rhBMP7 and rhTGFbeta1 were further tested and showed the same effect. To explore the mechanism, the expression of TGFbetatype I and II receptors, ALK5, ALK2, ALK3, ALK6, TGFbetaRII, BMPRII, ActRII was studied. ALK6 showed increase by the rhTGFbeta1 or rhTGFbeta3 treatment. ALK6 protein expression also showed increase by rhTGFbeta3. rhTGFbeta1/rhTGFbeta3 induced ALK6 up-regulation was inhibited by SD-208, a TGFbeta type I receptor inhibitor. Chondrogenesis by rhTGFbetal/rhTGFbeta3 or the combination between rhTGFbetal/rhTGFbeta3 and rhGDF5 also was diminished by SD-208. SMAD1/5/8 phosphorylation in nascent human mesenchymal stem cells (HMSCs) was stimulated weakly by rhGDF5 but strongly by rhBMP7. The rhGDF5 stimulated SMAD1/5/8 phosphorylation was enhanced by rhTGFbetal/rhTGFbeta3 but inhibited by SD-208. The rhBMP7 stimulated SMAD1/5/8 phosphorylation did not show influence by rhTGFbeta3 and SD-208. Our results indicated the potential involvement of ALK6 activation by rhTGFbetas in the synergy between rhTGFbetas and rhBMPs.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo I/metabolismo , Proteínas Morfogenéticas Ósseas/farmacologia , Condrogênese , Células-Tronco Mesenquimais/fisiologia , Fator de Crescimento Transformador beta3/farmacologia , Receptores de Ativinas Tipo I/metabolismo , Proteína Morfogenética Óssea 7 , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/fisiologia , Sinergismo Farmacológico , Fator 5 de Diferenciação de Crescimento , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Fosforilação , Pteridinas/farmacologia , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Regulação para Cima
15.
J Rheumatol ; 29(9): 1907-13, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12233885

RESUMO

OBJECTIVE: Treatment of autoimmune diseases with therapies that tolerize pathogenic lymphocytes may obviate the need for longterm global immunosuppression. In vitro, non-Fc receptor binding derivatives of anti-murine CD3 monoclonal antibodies tolerize type 1 T cells and stimulate type 2 T cells. Recently, a humanized non-FcR binding derivative of the anti-human CD3 Mab OKT3, huOKT3gamma1(ala-ala), has been described. We hypothesized that this Mab may be safe and efficacious in the treatment of type 1 T lymphocyte mediated chronic autoimmune diseases such as psoriatic arthritis (PsA). METHODS: In a Phase I/II trial, 7 patients with PsA were treated with escalating daily doses of huOKT3gamma1(ala-ala) for 12 to 14 days. Number of tender and swollen joints and a visual analog pain scale were used to rate disease activity at entry and Day 30 and Day 90 after treatment. RESULTS: At Day 30, 6 of 7 patients had > or = 75% improvement in the number of inflamed joints and an average 63% improvement on the patient pain scale. Two of 6 responders had sustained improvement at Day 90. No patient treated with an initial dose < or = 1 mg had significant side effects, nor did they have detectable increases in serum cytokines. One patient treated with 4 mg without escalation developed mild cytokine release symptoms associated with elevation of interleukin 10. Transient T cell depletion occurred following treatment with the maximum dose of 4 mg, which resolved by Day 30. Antiidiotypic antibodies developed in 2 patients; however, there was no concurrent decrease in efficacy. CONCLUSION: These data indicate that huOKT3gamma1(ala-ala) may be useful in treating PsA.


Assuntos
Artrite Psoriásica/tratamento farmacológico , Dose Máxima Tolerável , Muromonab-CD3/uso terapêutico , Adolescente , Adulto , Idoso , Artrite Psoriásica/diagnóstico , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Índice de Gravidade de Doença , Resultado do Tratamento
16.
N Engl J Med ; 346(22): 1692-8, 2002 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-12037148

RESUMO

BACKGROUND: Type 1 diabetes mellitus is a chronic autoimmune disease caused by the pathogenic action of T lymphocytes on insulin-producing beta cells. Previous clinical studies have shown that continuous immune suppression temporarily slows the loss of insulin production. Preclinical studies suggested that a monoclonal antibody against CD3 could reverse hyperglycemia at presentation and induce tolerance to recurrent disease. METHODS: We studied the effects of a nonactivating humanized monoclonal antibody against CD3--hOKT3gamma1(Ala-Ala)--on the loss of insulin production in patients with type 1 diabetes mellitus. Within 6 weeks after diagnosis, 24 patients were randomly assigned to receive either a single 14-day course of treatment with the monoclonal antibody or no antibody and were studied during the first year of disease. RESULTS: Treatment with the monoclonal antibody maintained or improved insulin production after one year in 9 of the 12 patients in the treatment group, whereas only 2 of the 12 controls had a sustained response (P=0.01). The treatment effect on insulin responses lasted for at least 12 months after diagnosis. Glycosylated hemoglobin levels and insulin doses were also reduced in the monoclonal-antibody group. No severe side effects occurred, and the most common side effects were fever, rash, and anemia. Clinical responses were associated with a change in the ratio of CD4+ T cells to CD8+ T cells 30 and 90 days after treatment. CONCLUSIONS: Treatment with hOKT3gamma1(Ala-Ala) mitigates the deterioration in insulin production and improves metabolic control during the first year of type 1 diabetes mellitus in the majority of patients. The mechanism of action of the anti-CD3 monoclonal antibody may involve direct effects on pathogenic T cells, the induction of populations of regulatory cells, or both.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Complexo CD3/imunologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Adolescente , Adulto , Anticorpos Monoclonais/efeitos adversos , Peptídeo C/sangue , Relação CD4-CD8 , Criança , Citocinas/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/imunologia , Feminino , Hemoglobinas Glicadas/análise , Humanos , Contagem de Linfócitos , Masculino
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