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1.
Langmuir ; 40(12): 6363-6374, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38470241

RESUMO

The programmed self-assembly of patchy nanoparticles (NPs) through a bottom-up approach is an efficient strategy for producing highly organized materials with a predetermined architecture. Herein, we report the preparation of di- and trivalent silica NPs with polystyrene (PS)/poly(4-vinylbenzyl azide) (PVBA) patches and assemble them in a THF mixture by lowering the solvent quality. Silica-PS/PVBA colloidal hybrid clusters were synthesized through the seeded growth emulsion copolymerization of styrene and 4-vinylbenzyl azide (VBA) in varying ratios. Subsequently, macromolecules on silica NPs originating from the copolymerization of growing PS or PVBA chains with the surface-grafted MMS compatibilizer are engineered by fine-tuning of polymer compositions or adjustment of solvent qualities. Moreover, multistage silica regrowth of tripod and tetrapod allowed a fine control of the patch-to-particle size ratio ranging from 0.69 to 1.54. Intriguingly, patchy silica NPs (1-, 2-, 3-PSNs) rather than hybrid clusters are successfully used as templates for multistep regrowth experiments, leading to the formation of silica NPs with a new morphology and size controllable PVBA/PS patches. Last but not least, combined with mesoscale dynamics simulations, the self-assembly kinetics of 2-PSN and 3-PSN into linear colloidal polymers and honeycomb-like lattices are studied. This work paves a new avenue for constructing colloidal polymers with a well-defined sequence and colloidal crystals with a predetermined architecture.

2.
Nano Lett ; 23(22): 10441-10448, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37818981

RESUMO

The low performance of sensors based on an all-dielectric metasurface limits their application compared to metallic counterparts. Here, for the first time, an all-dielectric BIC (bound states in the continuum) metasurface is employed for highly sensitive phase interrogation refractive index sensing. The proposed sensor is well analyzed, fabricated, and characterized. Experimentally, a high-performance BIC-based microfluidic sensing chip with a Q factor of 1200 is achieved by introducing symmetry breaking. A refractive index sensor with high figure of merit of 418 RIU-1 is demonstrated, which is beneficial to the phase interrogation. Notably, we measure a record phase interrogation sensitivity of 2.7 × 104 deg/RIU to the refractive index, thus enabling the all-dielectric BIC to rival the refractive index detection capabilities of metal-based sensors such as surface plasmon resonance. This scheme establishes a pivotal role of the all-dielectric metasurface in the field of ultrahigh sensitivity sensors and opens possibilities for trace detection in biochemical analysis and environment monitoring.

3.
Biochem Biophys Res Commun ; 683: 149116, 2023 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-37864924

RESUMO

Lipid droplets (LDs) are both energy storage and signaling organelles playing important roles in various physiological and pathological conditions. The mitochondria-ER contacts have been implicated in regulating the homeostasis of lipid droplets. However, our knowledge about the molecular mechanism behind this regulation is still limited. In this study, we identified CCDC127, a previously uncharacterized protein, as a new regulator of LDs by enhancing the mitochondria-ER contact sites (MERCS). Knockdown and overexpression of CCDC127 in HeLa cells significantly change the LDs abundance in opposite directions, suggesting that CCDC127 positively regulates the LDs. Additional analysis showed that CCDC127 localizes on the outer membrane of mitochondria through its N-terminus and promotes mitochondria fragmentation. Importantly, knockdown or overexpression of CCDC127 significantly down- or up-regulates, respectively, the formation of MERCS. Further experiments showed that CCDC127 is required to stabilize the MERCS tether protein VAPA. And overexpression or knockdown of VAPA reversed the effects of CCDC127 reduction or overexpression on LDs. Finally, we demonstrated that knocking down CCDC127 in the mesenchymal stem cells reduced their differentiation towards adipocytes. These findings provide a new molecular connection between LD homeostasis and MERCS regulation.


Assuntos
Gotículas Lipídicas , Mitocôndrias , Humanos , Células HeLa , Gotículas Lipídicas/metabolismo , Mitocôndrias/metabolismo , Receptores de Estrogênio/metabolismo , Homeostase , Metabolismo dos Lipídeos
4.
Ophthalmology ; 130(12): 1269-1278, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37480943

RESUMO

PURPOSE: To assess noninfectious uveitis (NIU) risk after coronavirus disease 2019 (COVID-19) vaccination in patients without a history of uveitis. DESIGN: A retrospective matched cohort study and self-controlled case series (SCCS) analysis using a longitudinal data asset with claims data from the OptumLabs Data Warehouse from December 11, 2020, through November 30, 2021. PARTICIPANTS: The matched cohort analysis included patients continuously enrolled for 730 days before December 11, 2020, who received a COVID-19 vaccination during the study period. This COVID-19-vaccinated group was matched to a COVID-19-unvaccinated historical cohort enrolled in 2018 and 2019. The SCCS design included individuals from the vaccinated cohort who experienced an NIU event during the study period. Enrollees with a history of uveitis were excluded. METHODS: Hazard ratios (HRs) were calculated using Cox proportional hazards models in the matched cohort design. Incidence rate ratios (IRRs) comparing NIU incidence in exposed risk periods after vaccination and unexposed control periods within individuals were calculated using conditional Poisson regression models in the SCCS design. Models were adjusted for age, recent receipt of non-COVID-19 vaccinations, corticosteroid or immunosuppressive use, and smoking history. Subgroup analyses were conducted by vaccination type and age group. MAIN OUTCOME MEASURES: Rates of NIU identified with International Classification of Diseases, Tenth Revision, codes. RESULTS: The matched cohort analysis included 4 611 378 patients, with 2 305 689 per cohort. The adjusted HR comparing NIU incidence in the COVID-19-vaccinated and unvaccinated cohort was 0.91 (95% confidence interval [CI], 0.75-1.10; P = 0.33). The SCCS analysis included 686 patients. The IRR comparing NIU risk after vaccination with risk during control intervals was 1.05 (95% CI, 0.89-1.23; P = 0.57). An increased risk was found in the subgroup aged 5 to 44 years (IRR, 1.40; 95% CI, 1.04-1.87; P = 0.024). CONCLUSIONS: The matched cohort and SCCS analyses did not detect increased NIU risk after COVID-19 vaccination overall in individuals without history of uveitis, providing reassurance about the vaccine's safety. The finding of increased risk in the youngest subgroup suggests heightened immune responses in younger individuals, warranting further investigation. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Assuntos
COVID-19 , Uveíte , Humanos , Estados Unidos/epidemiologia , Vacinas contra COVID-19/efeitos adversos , Estudos de Coortes , Estudos Retrospectivos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Uveíte/epidemiologia , Uveíte/etiologia , Vacinação/efeitos adversos
5.
FASEB J ; 36(4): e22233, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35225354

RESUMO

Cochlear outer hair cells (OHCs) are essential for hearing. A short, OHC-specific enhancer is necessary but not yet available for gene therapeutic applications in OHC damage. Such damage is a major cause of deafness. Prestin is a motor protein exclusively expressed in OHCs. We hypothesized that the cis-regulatory DNA fragment deletion of Slc26a5 would affect its expression. We tested this hypothesis by conducting CRISPR/Cas9-mediated large DNA fragment deletion of mouse Slc26a5 intron regions. First, starting from a ~13 kbp fragment, step-by-step, we narrowed down the sequence to a 1.4 kbp segment. By deleting either a 13 kbp or 1.4 kbp fragment, we observed delayed Prestin expression. Second, we showed that 1.4 kbp was an OHC-specific enhancer because enhanced green fluorescent protein (EGFP) was highly and specifically expressed in OHCs in a transgenic mouse where EGFP was driven by the 1.4 kbp segment. More importantly, specific EGFP was also driven by its homologous 398 bp fragment in human Slc26a5. This suggests that the enhancer is likely to be evolutionarily conserved across different species.


Assuntos
Sistemas CRISPR-Cas , Cóclea/metabolismo , Elementos Facilitadores Genéticos , Células Ciliadas Auditivas Externas/metabolismo , Íntrons , Proteínas Motores Moleculares/metabolismo , Transportadores de Sulfato/genética , Animais , Feminino , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Motores Moleculares/genética , Transportadores de Sulfato/antagonistas & inibidores , Transportadores de Sulfato/metabolismo
6.
Soft Matter ; 19(20): 3570-3579, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37159247

RESUMO

The formation and transformation of defects in confined liquid crystals are fascinating fundamental problems in soft matter. Here, we use molecular dynamics (MD) simulations to study ellipsoidal liquid crystals (LCs) confined in a spherical cavity, which significantly affects the orientation and translation of LC molecules near the surface. The liquid-crystal droplet can present the isotropic to smectic-B phase transition through the smectic-A phase, as the number density of the LC molecules increases. We further find the change of LC structure from bipolar to watermelon-striped during the phase transition from smectic-A (SmA) to smectic-B (SmB) phases. Our results reveal the transition from bipolar defects to the inhomogeneous structures with the coexistence of nematic and smectic phases in smectic liquid-crystal droplets. We also study the influence of the sphere size in the range of 10σ0 ≤ Rsphere ≤ 50σ0 on the structural inhomogeneities. It shows a weak dependence on the sphere size. We further focus on how the structures can be affected by the interaction strength εGB-LJ. Interestingly, we find the watermelon-striped structure can be changed into a configuration with four defects at the vertices of a tetrahedron upon increasing the interaction strength. The liquid crystals at a strong interaction strength of εGB-LJ = 10.0ε0 show the two-dimensional nematic phase at the surface. We further present an explanation for the origin of the striped-pattern formation. Our results highlight the potential for using confinement to control these defects and their associated nanostructural heterogeneity.

7.
J Chem Phys ; 159(10)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37681699

RESUMO

Confined liquid crystals (LCs) exhibit complex and intriguing structures, which are fascinating fundamental problems in soft matter. The helical structure of cylindrical cavities is of great importance in LC studies, particularly for their application in optical devices. In this study, we employ molecular dynamics simulations to explore the behavior of achiral smectic-B LCs confined in narrow cylindrical cavities, where geometric frustration plays an important role. By increasing the cylinder size, LCs exhibit a transition from multi-helical to layered structures. Notably, we observe two stable structures, namely the helical structure and the layered structure, at moderate cylinder size. We also investigate the effects of the arrangement of cylindrical wall particles (hexagonal or square array) and anchoring strength on the LC structure. Our findings reveal that both the hexagonal array and strong anchoring strength promote the formation of helical structures. Our study provides novel insights into the confinement physics of LCs and highlights the potential for achieving helical structures in achiral LCs, which will expand the future applications of LCs.

8.
J Chem Phys ; 158(10): 104902, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36922133

RESUMO

Normally, defects in two-dimensional, circular, confined liquid crystals can be classified into four types based on the position of singularities formed by liquid crystal molecules, i.e., the singularities located inside the circle, at the boundary, outside the circle, and outside the circle at infinity. However, it is considered difficult for small aspect ratio liquid crystals to generate all these four types of defects. In this study, we use molecular dynamics simulation to investigate the defect formed in Gay-Berne, ellipsoidal liquid crystals, with small aspect ratios confined in a circular cavity. As expected, we only find two types of defects (inside the circle and at the boundary) in circular, confined, Gay-Berne ellipsoids under static conditions at various densities, aspect ratios, and interactions between the wall and liquid crystals. However, when introducing an external field to the system, four types of defects can be observed. With increasing the strength of the external field, the singularities in the circular, confined system change from the inside to the boundary and the outside, and the farthest position that the singularities can reach depends on the strength of the external field. We further introduce an alternating, triangular wave, external field to the system to check if we can observe the transformation of different defects within an oscillating period. We find that the position of the singularities greatly depends on the oscillating intensity and oscillating period. By changing the oscillating intensity and oscillating period of the external field, the defect types can be adjusted, and the transformation between different defects can be easily observed. This provides a feasible way to modulate liquid crystal defects and investigate the transformation between different defects.

9.
J Chem Phys ; 159(22)2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38063227

RESUMO

Molecular dynamics simulations were used to analyze the mechanical properties and failure processes of poly(p-phenylene-terephthalamide) (PPTA), poly(p-phenylene-benzimidazole-terephthalamide) (PBIA), PBIA-PPTA (formed by 1:1 copolymerization of PPTA and PBIA), and poly(p-phenylene-benzobisoxazole) (PBO) crystals at different strain rates and temperatures. The failure stress and strain were found to be linear with the temperature and logarithmic strain rate. Moreover, based on the kinetic theory of fracture and the comprehensive simulation results, we formulated a model that describes the failure stress of the aforementioned crystals under varying strain rates and temperatures. Through the analysis of the failure process, we found that in PPTA, PBIA, and PBIA-PPTA crystals, the bond failure probability is correlated with the strain rate and temperature. The examination of bond lengths and angles unveiled that bonds with larger initial aligning angles are more susceptible to failure during the strain process. Intriguingly, the stretching process induced a conformational change in the PBO molecular chain, leading to a deviation from the linear relation in its stress-strain curve.

10.
Bioprocess Biosyst Eng ; 46(4): 611-620, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36735093

RESUMO

This work aimed to study the efficiency of nano- and micro- fiber membranes in immobilizing Actinobacillus succinogenes CCTCC M2012036 for succinic acid production. Among the four kinds of electrospun nanofiber membranes of cellulose acetate, chitosan, poly(vinyl alcohol) (PVA) and chitosan-PVA, the cellulose acetate nanofiber membrane-immobilized cells performed the best with a succinic acid concentration and yield to be 27.3 ± 3.5 g/L and 70.9 ± 5.8%. The cell-immobilized viscose microfiber membrane presented good reuse stability, and 17 batches of fermentation without activity loss were realized with the highest succinic acid yield of 83.20%. A microfiber membrane bioreactor was further constructed with the cell-immobilized viscose microfiber membrane to perform fermentation on a larger scale, and the concentration, yield and productivity of succinic acid were 73.20 g/L, 86.50% and 1.49 g/(L⋅h) using a fed-batch strategy, which were 124.30%, 127.60% and 124.2% of those obtained in the traditional fermenter. This study provided an approach for improving the practicality of biological succinic acid production.


Assuntos
Actinobacillus , Quitosana , Ácido Succínico , Reatores Biológicos , Fermentação
11.
Metab Eng ; 73: 201-213, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35934176

RESUMO

The oxidized kaurene (Ox-Kau) compounds are the core structures of many important diterpenoids with biological activities and economical values. However, easy access to diverse Ox-Kau products is still limited by low natural abundance, and large-scale manufacture remain challenging due to lack of proper heterologous production. To achieve an abundant source alternative to natural extracts, we here report a highly effective Escherichia coli-based platform for the de novo production of multiple Ox-Kau molecules from simple carbon source. Pathway optimization in prokaryotic cells through modification of transmembrane CYP450 oxidases, cytochrome b5 co-expression and AlphaFold-based protein engineering improved a 50-fold yield of steviol (1.07 g L-1), a key intermediate in the kaurenoid biosynthesis. Combinatorial biosynthetic strategy further led to a series of oxidized derivatives (20-600 mg L-1) with rich oxygenated functional groups on C3, C7, C16 and C19 previously hard to be introduced. Our engineered strains not only laid a foundation for realizing the industrial fermentation of gram-scale ent-kaurene diterpenoids, but also provided a reliable platform for characterization and utilization of kaurene-modifying oxidases, which may generate naturally rare or unnatural ent-kaurenoids with potential bioactivity.


Assuntos
Alquil e Aril Transferases , Diterpenos do Tipo Caurano , Diterpenos , Alquil e Aril Transferases/metabolismo , Diterpenos/metabolismo , Diterpenos do Tipo Caurano/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Plantas/metabolismo
12.
Ophthalmology ; 129(10): 1096-1106, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35588945

RESUMO

PURPOSE: To determine the dose-dependent risk of systemic corticosteroids (SCs) and the risk of other immunosuppressive therapies on coronavirus disease 2019 (COVID-19) infection, hospitalization, and death in patients with noninfectious uveitis (NIU). DESIGN: A retrospective cohort study from January 20, 2020, to December 31, 2020 (an era before widespread COVID-19 vaccination), using the Optum Labs Data Warehouse, a US national de-identified claims database. PARTICIPANTS: Patients who had at least 1 NIU diagnosis from January 1, 2017. METHODS: Unadjusted and adjusted hazard ratios (HRs) were estimated for each variable and COVID-19 outcome using Cox proportional hazards models, with time-updated dichotomous indicators for outpatient immunosuppressive medication exposure. To assess the dose-dependent effect of SC exposure, the average daily dose of prednisone over the exposed interval was included in the adjusted models as a continuous variable, in addition to the dichotomous variable. MAIN OUTCOME MEASURES: Incidence rates of COVID-19 infection, COVID-19-related hospitalization, and COVID-19-related in-hospital death. RESULTS: This study included 52 286 NIU patients of whom 12 000 (23.0%) were exposed to immunosuppressive medications during the risk period. In adjusted models, exposure to SCs was associated with increased risk of COVID-19 infection (HR, 2.66; 95% confidence interval [CI], 2.19-3.24; P < 0.001), hospitalization (HR, 3.26; 95% CI, 2.46-4.33; P < 0.001), and in-hospital death (HR, 1.99; 95% CI, 0.93-4.27; P = 0.08). Furthermore, incremental increases in the dosage of SCs were associated with a greater risk for these outcomes. Although tumor necrosis factor-α (TNF-α) inhibitors were associated with an increased risk of infection (HR, 1.48; 95% CI, 1.08-2.04; P = 0.02), other immunosuppressive treatments did not increase the risk of COVID-19 infection, hospitalization, or death. CONCLUSIONS: This study from an era before widespread COVID-19 vaccination demonstrates that outpatient SC exposure is associated with greater risk of COVID-19 infection and severe outcomes in patients with NIU. Future studies should evaluate the impact of immunosuppression in vaccinated NIU patients. Limiting exposure to SCs and use of alternative therapies may be warranted.


Assuntos
COVID-19 , Imunossupressores , Uveíte , Corticosteroides/efeitos adversos , COVID-19/complicações , COVID-19/epidemiologia , Vacinas contra COVID-19/efeitos adversos , Mortalidade Hospitalar , Hospitalização , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Prednisona/uso terapêutico , Estudos Retrospectivos , Resultado do Tratamento , Fator de Necrose Tumoral alfa/uso terapêutico , Uveíte/tratamento farmacológico
13.
Ophthalmology ; 129(3): 334-343, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34648828

RESUMO

PURPOSE: To identify if noninfectious uveitis (NIU) is associated with a greater risk of Coronavirus Disease 2019 (COVID-19) infection, hospitalization, and death. DESIGN: A retrospective cohort study from January 20, 2020 to December 31, 2020, using a national claims-based database. PARTICIPANTS: Enrollees who had continuous enrollment with both medical and pharmacy coverage for 3 years before January 20, 2020. Patients with an NIU diagnosis within 3 years of the start of the study were included in the NIU cohort. Those with infectious uveitis codes or new NIU diagnoses during the risk period were excluded. METHODS: Cox proportional hazard models were used to identify unadjusted hazard ratios (HRs) and adjusted HRs for all covariates for each outcome measure. Adjusted models accounted for patient demographics, health status, and immunosuppressive medication use during the risk period. MAIN OUTCOME MEASURES: Rates of COVID-19 infection, COVID-19-related hospitalization, and COVID-19-related in-hospital death identified with International Classification of Disease 10th revision codes. RESULTS: This study included 5 806 227 patients, of whom 29 869 (0.5%) had a diagnosis of NIU. On unadjusted analysis, patients with NIU had a higher rate of COVID-19 infection (5.7% vs. 4.5%, P < 0.001), COVID-19-related hospitalization (1.2% vs. 0.6%, P < 0.001), and COVID-19-related death (0.3% vs. 0.1%, P < 0.001). However, in adjusted models, NIU was not associated with a greater risk of COVID-19 infection (HR, 1.05; 95% confidence interval [CI], 1.00-1.10; P = 0.04), hospitalization (HR, 0.98; 95% CI, 0.88-1.09; P = 0.67), or death (HR, 0.90, 95% CI, 0.72-1.13, P = 0.37). Use of systemic corticosteroids was significantly associated with a higher risk of COVID-19 infection, hospitalization, and death. CONCLUSIONS: Patients with NIU were significantly more likely to be infected with COVID-19 and experience severe disease outcomes. However, this association was due to the demographics, comorbidities, and medications of patients with NIU, rather than NIU alone. Patients using systemic corticosteroids were significantly more likely to be infected with COVID-19 and were at greater risk of hospitalization and in-hospital death. Additional investigation is necessary to identify the impact of corticosteroid exposure on COVID-19-related outcomes.


Assuntos
COVID-19/epidemiologia , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Revisão da Utilização de Seguros/estatística & dados numéricos , SARS-CoV-2 , Uveíte/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bases de Dados Factuais , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Estados Unidos/epidemiologia , Uveíte/diagnóstico , Uveíte/tratamento farmacológico
14.
Soft Matter ; 18(13): 2654-2662, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35311843

RESUMO

Colloidal cubic diamond crystals with low-coordinated and staggered structures could display a wide photonic bandgap at low refractive index contrasts, which makes them extremely valuable for photonic applications. However, self-assembly of cubic diamond crystals using simple colloidal building blocks is still considerably challenging, due to their low packing fraction and mechanical instability. Here we propose a new strategy for constructing colloidal cubic diamond crystals through cooperative self-assembly of surface-anisotropic triblock Janus colloids and isotropic colloidal spheres into superlattices. In self-assembly, cooperativity is achieved by tuning the interaction and particle size ratio of colloidal building blocks. The pyrochlore lattice formed by self-assembly of triblock Janus colloids acts as a soft template to direct the packing of colloidal spheres into cubic diamond lattices. Numerical simulations show that this cooperative self-assembly strategy works well in a large range of particle size ratio of these two species. Moreover, photonic band structure calculations reveal that the resulting cubic diamond lattices exhibit wide and complete photonic bandgaps and the width and frequency of the bandgaps can also be easily adjusted by tuning the particle size ratio. Our work will open up a promising avenue toward photonic bandgap materials by cooperative self-assembly employing surface-anisotropic Janus or patchy colloids as a soft template.

15.
Soft Matter ; 18(13): 2569-2576, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35293929

RESUMO

Using simple achiral building blocks modulated by an external field to achieve chiral liquid crystal phases remains a challenge. In this study, a chiral helix liquid crystal phase is obtained for a simple Gay-Berne ellipsoid model under an alternating external field by using molecular dynamics simulations. Our results show that the chiral helix liquid crystal phase can be observed in a wide range of external field strengths when the oscillation period is smaller than the rotational characteristic diffusion timescale of ellipsoids. In addition, we find that the pitch and tilt angle of the helix structure can also be adjusted by changing the strength and oscillation period of the applied alternating external field. This may provide a feasible route for the regulation of chiral liquid crystal phases by an alternating external field.

16.
Phys Chem Chem Phys ; 24(13): 7874-7881, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35302134

RESUMO

Numerous crystals and Frank-Kasper phases in two-dimensional (2D) systems of soft particles have been presented by theoretical investigations. How to realize 2D crystals or Frank-Kasper phases via the direct self-assembly of three-dimensional (3D) systems remains an important issue. Here, through numerical simulations, we report the surprising finding of multiple 2D crystal structures in bilayered lamellae from the direct self-assembly of 3D systems of soft Janus particles. With varying the patch size and particle density, soft Janus particles, which exhibit very similar self-assembly behavior to giant amphiphiles, spontaneously form ordered bilayered lamellae. Within each layer of the bilayered lamellae, we find abundant highly-ordered 2D crystals including the Frank-Kasper σ phase and open kagome lattice. The kinetic mechanisms of the formation of these 2D crystals within the layers are revealed, and include a classical one-step nucleation mechanism and a two-step nucleation mechanism. Our findings suggest a simple route towards 2D crystals via the direct self-assembly of 3D systems of amphiphilic Janus building blocks.

17.
Int J Clin Pharmacol Ther ; 60(12): 509-514, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36197788

RESUMO

Patients with advanced gastric cancer experience rapid disease progression with limited survival, high mortality, and a lack of surgical options. Thus, radiochemotherapy or a combination of chemotherapeutics with targeted therapy is the mainstay of treatment. In comparison to the treatment of other malignant tumors, in gastric cancer, the development of molecularly targeted drugs has been relatively slow. Currently, there are two major classes of molecularly targeted drug regimens that have achieved a certain efficacy in clinical practice: anti-vascular endothelial growth factor (anti-VEGF) therapy and anti-epidermal growth factor receptor (anti-EGFR) therapy. Trastuzumab has been approved as the standard of care for first-line treatment in advanced human epidermal growth factor receptor 2 (HER2)-positive gastric cancer. Ramucirumab in combination with paclitaxel is the recommended regimen for second-line treatment, and apatinib is recommended as third-line treatment. This review summarizes the current status of targeted therapies in the treatment of gastric cancer and gives a perspective on the future.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Trastuzumab/uso terapêutico , Paclitaxel , Terapia de Alvo Molecular
18.
Clin Infect Dis ; 73(6): 949-956, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-33580245

RESUMO

BACKGROUND: The recombinant zoster vaccine had over 90% efficacy in preventing herpes zoster in clinical trials. However, its effectiveness outside of a clinical trial setting has not been investigated. This study aimed to assess the effectiveness of the recombinant zoster vaccine in general practice. METHODS: A de-identified administrative claims database, the OptumLabs Data Warehouse, was used to conduct this retrospective cohort study to assess the effectiveness of the recombinant zoster vaccine against herpes zoster in nonimmunocompromised, vaccine age-eligible individuals enrolled in the database for ≥365 days. RESULTS: A total of 4 769 819 adults were included in this study, with 173 745 (3.6%) adults receiving 2 valid doses of the recombinant zoster vaccine. The incidence rate of herpes zoster was 258.8 (95% confidence interval [CI], 230.0-289.4) cases per 100 000 person-years in vaccinated persons compared with 893.1 (95% CI, 886.2-900.0) in unvaccinated persons. Recombinant zoster vaccine effectiveness was 85.5% (95% CI, 83.5-87.3%) overall, with an effectiveness of 86.8% (95% CI, 84.6-88.7%) in individuals 50 to 79 years old compared with 80.3% (95% CI, 75.1-84.3%) in individuals aged 80 and older. In patients with a history of live zoster vaccine within 5 years of study inclusion, vaccine effectiveness was 84.8% (95% CI, 75.3-90.7%). CONCLUSIONS: Recombinant zoster vaccine effectiveness against herpes zoster was high in a real-world setting. Given the low vaccine coverage and high effectiveness, a major public health effort is needed to identify and address barriers to vaccination and increase immunization rates.


Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Herpes Zoster/epidemiologia , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos/epidemiologia
19.
Ophthalmology ; 128(12): 1699-1707, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33892049

RESUMO

PURPOSE: To examine the effectiveness of the recombinant zoster vaccine (RZV) for preventing herpes zoster ophthalmicus (HZO) in the general United States population. DESIGN: Retrospective, observational cohort study. PARTICIPANTS: Individuals enrolled in the OptumLabs Data Warehouse (OLDW; OptumLabs, Cambridge, MA) who were age eligible for herpes zoster (HZ) vaccination (≥50 years of age) from 2018 through 2019. The OLDW is a longitudinal, de-identified administrative claims and electronic health record database of patients in the United States with commercial insurance, Medicare Part D, or Medicare Advantage METHODS: Patients were required to have 365 days or more of continuous enrollment to be eligible. Those with a diagnosis code of HZ or an immunocompromising condition within 1 year before study inclusion were excluded. Vaccination with the RZV was ascertained by Current Procedural Terminology codes, and HZO was ascertained by International Classification of Diseases, Tenth Revision, codes. Cox proportional hazards regression models were used to estimate the hazard ratio of HZO associated with RZV, and inverse-probability weighting was used to control for confounding. Vaccine effectiveness was calculated from hazard ratios. MAIN OUTCOME MEASURES: Incidence of HZO in vaccinated versus unvaccinated person-times and vaccine effectiveness were assessed. RESULTS: From January 1, 2018, through December 31, 2019, a total of 4 842 579 individuals were included in this study. One hundred seventy-seven thousand two hundred eighty-nine (3.7%) received 2 valid doses of RZV. The incidence rate of HZO was 25.5 cases (95% confidence interval [CI], 17.4-35.8 cases) per 100 000 person-years in the vaccinated group compared with 76.7 cases (95% CI, 74.7-78.7 cases) in the unvaccinated group. The overall adjusted effectiveness of RZV against HZO was 89.1% (95% CI, 82.9%-93.0%). CONCLUSIONS: The effectiveness of RZV against HZO in individuals 50 years of age and older is high in a clinical setting. However, the low vaccination rate in this study highlights the public health need to increase HZV use. Ophthalmologists can play an important role in recommending vaccination to eligible patients.


Assuntos
Herpes Zoster Oftálmico/prevenção & controle , Vacina contra Herpes Zoster/administração & dosagem , Eficácia de Vacinas/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Current Procedural Terminology , Bases de Dados Factuais/estatística & dados numéricos , Registros Eletrônicos de Saúde/estatística & dados numéricos , Feminino , Seguimentos , Herpes Zoster Oftálmico/epidemiologia , Humanos , Incidência , Masculino , Medicare Part D/estatística & dados numéricos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Estados Unidos/epidemiologia , Vacinação , Vacinas Sintéticas
20.
Dev Dyn ; 249(2): 173-186, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31487081

RESUMO

BACKGROUND: Conditional loss-of-function studies are widely conducted using the Cre/Loxp system because this helps circumvent embryonic or neonatal lethality problems. However, Cre strains specific to the inner ear are lacking, and thus lethality frequently occurs even in conditional knockout studies. RESULTS: Here, we report a Rorb-IRES-Cre knockin mouse strain in which the Cre recapitulates the expression pattern of endogenous Rorb (RAR-related orphan receptor beta). Analysis of Rorb-IRES-Cre/+; Rosa26-CAG-LSL-tdTomato/+ cochlear samples revealed that tdTomato was expressed at the apical turn only by E12.5. TdTomato was observed in the apical and middle turns but was minimally expressed in the basal turn at E15.5, E18.5, and P5. However, most of the auditory hair cells (HCs) and supporting cells (SCs) in all three turns were tdTomato+ at P15 and P30. Intriguingly, no tdTomato+ vestibular cells were detected until P5 and a few cells were present at P15 and P30. Finally, we also confirmed Rorb mRNA and protein expression in cochlear HCs and SCs at P30. CONCLUSIONS: We reveal that Rorb expression exhibits an apical-to-basal gradient in cochleae. The cochlear-specific and apical-to-basal-gradient Rorb Cre activity should enable discrimination of gene functions in cochlear vs vestibular regions as well as low-frequency vs high-frequency regions in the cochlea.


Assuntos
Cóclea/metabolismo , Células Ciliadas Auditivas/metabolismo , Células Labirínticas de Suporte/metabolismo , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Animais , Cóclea/citologia , Orelha Interna/metabolismo , Integrases/genética , Integrases/metabolismo , Camundongos , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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