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1.
Mol Cell Proteomics ; : 100804, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38901673

RESUMO

Osmotic stress significantly hampers plant growth and crop yields, emphasizing the need for a thorough comprehension of the underlying molecular responses. Previous research has demonstrated that osmotic stress rapidly induces calcium influx and signaling, along with the activation of a specific subset of protein kinases, notably the Raf-SnRK2 kinase cascades within minutes. However, the intricate interplay between calcium signaling and the activation of RAF-SnRK2 kinase cascades remains elusive. Here in this study, we discovered that Raf-like protein (RAF) kinases undergo hyperphosphorylation in response to osmotic shocks. Intriguingly, treatment with the calcium chelator EGTA robustly activates RAF-SnRK2 cascades, mirroring the effects of osmotic treatment. Utilizing high-throughput DIA-based phosphoproteomics, we unveiled the global impact of EGTA on protein phosphorylation. Beyond the activation of RAFs and sucrose non-fermenting-1-related protein kinase 2s (SnRK2s), EGTA treatment also activates mitogen-activated protein kinase (MAPKs) cascades, Calcium-dependent protein kinases (CDPKs), and receptor-like protein kinases, etc. Through overlapping assays, we identified potential roles of mitogen-activated protein kinase kinase kinase kinases (MAP4Ks) and receptor-like protein kinases in the osmotic-stress-induced activation of RAF-SnRK2 cascades. Our findings illuminate the regulation of phosphorylation and cellular events by Ca2+ signaling, offering insights into the (exocellular) Ca2+ deprivation during early hyperosmolality sensing and signaling.

2.
Opt Express ; 32(9): 16351-16361, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859264

RESUMO

Active control of induced reflection is crucial for many potential applications ranging from slowing light to biosensing devices. However, most previous approaches require patterned nanostructures to achieve controllable induced reflection, which hinders their further applications due to complicated architectures. Herein, we propose a lithography-free multilayered structure to achieve the induced reflection through the coupling of dual-topological-interface-states. The multilayers consist of two one-dimensional (1D) photonic crystals (PCs) and an Ag film separated by a Spacer, topological edge state (TES) and topological Tamm state (TTS) can be excited simultaneously and their coupling induces the reflection window. The coupled-oscillator model is proposed to mimic the coupling between the TES and TTS, and the analytical results are in good agreement with finite element method (FEM). In addition, the TES-TTS induced reflection is robust to the variation of structural parameters. By integrating an ultra-thin phase-change film of Ge2Sb2Te5 (GST) into the multilayers, the induced reflection can be switched through the phase transition of the GST film. The multipole decomposition reveals that the vanished reflection window is arising from the disappearance of TTS associated with the toroidal dipole (TD) mode.

3.
Opt Express ; 32(8): 13978-13985, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859355

RESUMO

Optical chirality is highly demanded for biochemical sensing, spectral detection, and advanced imaging, however, conventional design schemes for chiral metamaterials require highly computational cost due to the trial-and-error strategy, and it is crucial to accelerate the design process particularly in comparably simple planar chiral metamaterials. Herein, we construct a bidirectional deep learning (BDL) network consists of spectra predicting network (SPN) and design predicting network (DPN) to accelerate the prediction of spectra and inverse design of chiroptical response of planar chiral metamaterials. It is shown that the proposed BDL network can accelerate the design process and exhibit high prediction accuracy. The average process of prediction only takes ∼15 ms, which is 1 in 40000 compared to finite-difference time-domain (FDTD). The mean-square error (MSE) loss of forward and inverse prediction reaches 0.0085 after 100 epochs. Over 95.2% of training samples have MSE ≤ 0.0042 and MSE ≤ 0.0044 for SPN and DPN, respectively; indicating that the BDL network is robust in the inverse deign without underfitting or overfitting for both SPN and DPN. Our founding shows great potentials in accelerating the on-demand design of planar chiral metamaterials.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38814595

RESUMO

Objective: Our aim was to analyze the risk factors of hypertensive disorders of pregnancy (HDP) and explore its influence on fetal risk factors, infant's blood cells and markers of inflammation. Methods: A total of 123 patients with HDP were in the HDP group, and 121 healthy pregnant women were selected as the control group. The general clinical data of the participants were recorded. Statistics of maternal and infant outcomes, delivery methods, routine blood lab results and coagulation factors of the newborn were recorded. Univariate analysis and multi-factor analysis were used to explore the risk factors for HDP. Results: The overall incidence of poor maternal outcomes in the HDP group was higher than in the control group. The incidence of premature delivery; postpartum hemorrhage; coagulopathy; placental abruption; heart failure and hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome was significantly higher in the HDP group than in the control group (P < .05). The cesarean section rate in the HDP group was significantly higher than in the control group (P < .05). The overall incidence of poor outcomes in fetuses and newborns in the HDP group was higher than in the control group. The incidence of infant low birth weight, intraventricular hemorrhage (IVH), neonatal respiratory distress syndrome (NRDS), asphyxia and all-cause neonatal death were higher than in the control group (P < .05). The incidence of small gestational age (SGA), fetal distress and intrauterine death in the HDP group were higher than in the control group (P < .05). In the HDP group, neonatal white blood cells (WBC), neutrophils (NEUT) and platelets (PLT) were significantly lower than in the control group (P < .05), while hemoglobin (Hgb) and hematocrit (Hct) were higher (P < .05). Conclusions: HDP endangers the health of mother and infant; Age, body mass index (BMI) (>24 kg/m2), parity, history of hypertension, family history of hypertension and other factors may be involved in the occurrence and development of HDP.

5.
J Neurosci Res ; 101(7): 1154-1169, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36854050

RESUMO

Mild cognitive impairment is a nonmotor complication in Parkinson's disease (PD) that have a high risk of developing dementia. White matter is associated with cognitive function in PD and the alterations may occur before the symptoms of the disease. Previous diffusion tensor imaging (DTI) studies lacked specificity to characterize the concrete contributions of distinct white matter tissue properties. This may lead to inconsistent conclusions about the alteration of white matter microstructure. Here, we used neurite orientation dispersion and density imaging (NODDI) and white matter fiber clustering method to uncover local white matter microstructures in PD with mild cognitive impairment (PD-MCI). This study included 23 PD-MCI and 20 PD with normal cognition (PD-NC) and 21 healthy controls (HC). To probe specific and fine-grained differences, metrics of NODDI and DTI in white matter fiber clusters were evaluated using along-tract analysis. Our results showed that PD-MCI patients had significantly lower neurite density index (NDI) and orientation dispersion index (ODI) in white matter fiber clusters in the prefrontal region. Correlation analysis and receiver operating characteristic (ROC) analysis revealed that the diagnostic performance of NODDI-derived metrics in cingulum bundle (2 clusters) and thalamo-frontal (2 clusters) were superior to DTI metrics. Our study provides a more specific insight to uncover local white matter abnormalities in PD-MCI, which benefit understanding the underlying mechanism of cognitive decline in PD and predicting the disease in advance.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Substância Branca , Humanos , Imagem de Tensor de Difusão/métodos , Neuritos , Substância Branca/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia
6.
Opt Express ; 31(20): 32393-32403, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37859044

RESUMO

We propose a heterogeneous structure, which are composed of two valley photonic crystals (VPCs) with opposite valley Chern numbers and air channel. With the increasing width of the air channel, valley-locked waveguide modes are found in topological bandgap by analyzing energy bands. Finite element method (FEM) simulation results show that the fundamental and high order modes are valley-locked, propagating unidirectionally under the excitation of chiral source, and possess higher flux compared to the valley-locked topological edge state in the domain wall. Besides, the immunity to backscattering in bend and couplers, and the robustness to random disorders are discussed in detail. We also investigate the one-way multimode interference (MMI) effect based on valley-locked waveguide modes, and design topological beam splitters. Our study provides a novel idea for topological transport with high flux, and more freedom to design valley-locked waveguide devices, including bends, couplers and splitters.

7.
Opt Express ; 31(1): 774-775, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36607010

RESUMO

Erratum to "Creating perfect composite vortex beams with a single all-dielectric geometric metasurface." [Opt. Express30, 40231 (2022)10.1364/OE.475158]. Here are some mistakes in the paper, which needs to be revised.

8.
Invest New Drugs ; 41(5): 664-676, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37542666

RESUMO

Liposomal doxorubicin exhibits stronger drug accumulation at the tumor site due to the Enhanced Permeability and Retention (EPR) effect. However, the prognosis for the patient is poor due to this drug's lack of targeting and tumor metastasis during treatment. Vascular epidermal growth factor receptor (VEGFR2) plays an important role in angiogenesis and cancer metastasis. To enhance antitumor efficacy of PEGylated liposomal doxorubicin, we constructed a VEGFR2-targeted and doxorubicin-loaded immunoliposome (Lipo-DOX-C00) by conjugating a VEGFR2-specific, single chain antibody fragment to DSPE-PEG2000-MAL, and then we inserted the antibody-conjugated polymer into liposomal doxorubicin (Lipo-DOX). The immunoliposome was formed uniformly with high affinity for VEGFR2. In vitro, Lipo-DOX-C00 enhanced doxorubicin internalization into LLC and 4T1 cells compared with non-conjugated, liposomal doxorubicin. In vivo, Lipo-DOX-C00 delivered DOX to tumor tissues effectively, which exhibited an improved antitumor and anti-metastasis efficacy in both LLC subcutaneous tumor models and 4T1 tumor models. In addition, the combined therapy of a VEGFR2-MICA bispecific antibody (JZC01) and Lipo-DOX-C00 achieved enhanced inhibition of cancer growth and metastasis due to activation of the immune system. Our study provides a promising approach to clinical application of liposomal doxorubicin.

9.
NMR Biomed ; 36(7): e4904, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36633539

RESUMO

The human visual pathway starts from the retina, passes through the retinogeniculate visual pathway, the optic radiation, and finally connects to the primary visual cortex. Diffusion MRI tractography is the only technology that can noninvasively reconstruct the visual pathway. However, complete and accurate visual pathway reconstruction is challenging because of the skull base environment and complex fiber geometries. Specifically, the optic nerve within the complex skull base environment can cause abnormal diffusion signals. The crossing and fanning fibers at the optic chiasm, and a sharp turn of Meyer's loop at the optic radiation, contribute to complex fiber geometries of the visual pathway. A fiber trajectory distribution (FTD) function-based tractography method of our previous work and several high sensitivity tractography methods can reveal these complex fiber geometries, but are accompanied by false-positive fibers. Thus, the related studies of the visual pathway mostly applied the expert region of interest selection strategy. However, interobserver variability is an issue in reconstructing an accurate visual pathway. In this paper, we propose a unified global tractography framework to automatically reconstruct the visual pathway. We first extend the FTD function to a high-order streamline differential equation for global trajectory estimation. At the global level, the tractography process is simplified as the estimation of global trajectory distribution coefficients by minimizing the cost between trajectory distribution and the selected directions under the prior guidance by introducing the tractography template as anatomic priors. Furthermore, we use a deep learning-based method and tractography template prior information to automatically generate the mask for tractography. The experimental results demonstrate that our proposed method can successfully reconstruct the visual pathway with high accuracy.


Assuntos
Demência Frontotemporal , Vias Visuais , Humanos , Vias Visuais/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Imageamento por Ressonância Magnética
10.
Plant Cell ; 32(8): 2621-2638, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32439826

RESUMO

Camalexin is a major phytoalexin that plays a crucial role in disease resistance in Arabidopsis (Arabidopsis thaliana). We previously characterized the regulation of camalexin biosynthesis by the mitogen-activated protein kinases MPK3 and MPK6 and their downstream transcription factor WRKY33. Here, we report that the pathogen-responsive CALCIUM-DEPENDENT PROTEIN KINASE5 (CPK5) and CPK6 also regulate camalexin biosynthesis in Arabidopsis. Chemically induced expression of constitutively active CPK5 or CPK6 variants was sufficient to induce camalexin biosynthesis in transgenic Arabidopsis plants. Consistently, the simultaneous mutation of CPK5 and CPK6 compromised camalexin production in Arabidopsis induced by the fungal pathogen Botrytis cinerea Moreover, we identified that WRKY33 functions downstream of CPK5/CPK6 to activate camalexin biosynthetic genes, thereby inducing camalexin biosynthesis. CPK5 and CPK6 interact with WRKY33 and phosphorylate its Thr-229 residue, leading to an increase in the DNA binding ability of WRKY33. By contrast, the MPK3/MPK6-mediated phosphorylation of WRKY33 on its N-terminal Ser residues enhances the transactivation activity of WRKY33. Furthermore, both gain- and loss-of-function genetic analyses demonstrated the cooperative regulation of camalexin biosynthesis by CPK5/CPK6 and MPK3/MPK6. Taken together, these findings indicate that WRKY33 functions as a convergent substrate of CPK5/CPK6 and MPK3/MPK6, which cooperatively regulate camalexin biosynthesis via the differential phospho-regulation of WRKY33 activity.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Vias Biossintéticas , Indóis/metabolismo , Tiazóis/metabolismo , Fatores de Transcrição/metabolismo , Arabidopsis/microbiologia , Botrytis , DNA de Plantas/metabolismo , Resistência à Doença , Regulação da Expressão Gênica de Plantas , Fosforilação , Doenças das Plantas/microbiologia , Ativação Transcricional/genética
11.
Plant Cell ; 32(9): 2806-2822, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32586913

RESUMO

The crosstalk between brassinosteroid (BR) and jasmonic acid (JA) signaling is crucial for plant growth and defense responses. However, the detailed interplay between BRs and JA remains obscure. Here, we found that the rice (Oryza sativa) Glycogen synthase kinase3 (GSK3)-like kinase OsGSK2, a conserved kinase serving as a key suppressor of BR signaling, enhanced antiviral defense and the JA response. We identified a member of the JASMONATE ZIM-domain (JAZ) family, OsJAZ4, as a OsGSK2 substrate and confirmed that OsGSK2 interacted with and phosphorylated OsJAZ4. We demonstrated that OsGSK2 disrupted the OsJAZ4-OsNINJA complex and OsJAZ4-OsJAZ11 dimerization by competitively binding to the ZIM domain, perhaps helping to facilitate the degradation of OsJAZ4 via the 26S proteasome pathway. We also showed that OsJAZ4 negatively modulated JA signaling and antiviral defense and that the BR pathway was involved in modulating the stability of OsJAZ4 protein in an OsCORONATINE INSENSITIVE1-dependent manner. Collectively, these results suggest that OsGSK2 enhances plant antiviral defenses by activating JA signaling as it directly interacts with, phosphorylates, and destabilizes OsJAZ4. Thus, our findings provide a clear link between BR and JA signaling.


Assuntos
Brassinosteroides/metabolismo , Ciclopentanos/metabolismo , Oryza/metabolismo , Oxilipinas/metabolismo , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Oryza/genética , Oryza/microbiologia , Fosforilação , Doenças das Plantas/virologia , Proteínas de Plantas/genética , Vírus de Plantas/patogenicidade , Plantas Geneticamente Modificadas , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Multimerização Proteica , Transdução de Sinais
12.
Opt Lett ; 48(24): 6488-6491, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38099780

RESUMO

Chiral quasi-bound states in the continuum (QBIC) offer novel mechanisms to achieve intrinsic chiroptical responses. However, current studies on chiral QBIC metasurfaces are restricted to the excitation of intrinsic chirality and fail to dynamically control its circular dichroism (CD) responses. Herein, we construct a phase-change metasurface based on paired Ge2Sb2Te5 (GST) bars to demonstrate the dynamic control of the CD responses of chiral QBIC. The modified coupled mode theory (CMT) is proposed to evaluate the intrinsic chirality, and the predicted results are in good agreement with the finite-difference time-domain (FDTD) results. The maximal intrinsic chirality is associated with the spin-selected dipole mode, i.e., the coupled magnetic dipole (MD) QBIC mode for the left-handed circularly polarized (LCP) light and the decoupled electric dipole (ED) QBIC mode for the right-handed circularly polarized (RCP) light. By varying the volume fraction of GST, the location of chiral BIC can be tuned linearly, and the corresponding chiral response can be switched.

13.
Appl Opt ; 62(9): 2292-2299, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-37132868

RESUMO

Photothermoelectric conversion in chiral metasurfaces with thermoelectric material provides an effective way to achieve circular polarization recognition. In this paper, we propose a circular-polarization-sensitive photodetector in a mid-infrared region, which is mainly composed of an asymmetric silicon grating, a film of gold (Au), and the thermoelectric B i 2 T e 3 layer. The asymmetric silicon grating with the Au layer achieves high circular dichroism absorption due to a lack of mirror symmetry, which results in a different temperature increasing on the surface of the B i 2 T e 3 layer under right-handed circularly polarized (RCP) and left-handed circularly polarized (LCP) excitation. Then the chiral Seebeck voltage and output power density are obtained, thanks to the thermoelectric effect of B i 2 T e 3. All the works are based on the finite element method, and the simulation results are conducted by the Wave Optics module of COMSOL, which is coupled with the Heat Transfer module and Thermoelectric module of COMSOL. When the incident flux is 1.0W/c m 2, the output power density under RCP (LCP) light reaches 0.96m W/c m 2 (0.01m W/c m 2) at a resonant wavelength, which achieves a high capability of detecting circular polarization. Besides, the proposed structure shows a faster response time than that of other plasmonic photodetectors. Our design provides a novel, to the best of our knowledge, method for chiral imaging, chiral molecular detection, and so on.

14.
Appl Opt ; 62(22): 5969-5975, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706950

RESUMO

For many high-precision applications such as filtering, sensing, and photodetection, active control of resonant responses of metasurfaces is crucial. Herein, we demonstrate that active control of resonant asymmetric transmission can be realized based on the topological edge state (TES) of an ultra-thin G e 2 S b 2 T e 5 (GST) film in a photonic crystal grating (PCG). The PCG is composed of two pairs of one-dimensional photonic crystals (PCs) separated by a GST film. The phase change of the GST film re-distributes the field distributions of the PCG; thus active control of narrowband asymmetric transmission can be achieved due to the switch of the on-off state of the TES. According to multipole decompositions, the appearance and disappearance of the synergistically reduced dipole modes are responsible for the high-contrast asymmetric transmission of the PCG. In addition, the asymmetric transmission performances are robust to the variation of structural parameters, and good unidirectional transmission performances with a high peak transmission and high contrast ratio can be balanced, as the layer number of the two PCs is set as four. By changing the crystallization fraction of GST, the peak transmission and peak contrast ratio of asymmetric transmission can be flexibly tuned with the resonance locations kept almost the same.

15.
BMC Pediatr ; 23(1): 136, 2023 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-36966278

RESUMO

OBJECTIVE: To investigate the perinatal and in-hospital risk factors associated with the high incidence of amblyopia in preterm infants and to analyze the correlation between the amblyopia and neurodevelopment. METHODS: Children discharged from the neonatal intensive care unit (NICU) at 12 months of corrected gestational age were retrospectively included in this study. Ocular screening was performed in children. At the risk of amblyopia was determined according to the American Academy of Ophthalmology Guidelines for automated preschool vision screening factors. Differences in perinatal characteristics, complications during hospitalization, and treatment modalities between the two groups of children were analyzed, and multifactorial logistic regression analysis was used to identify the independent risk factors for amblyopia. The results of developmental assessment were collected retrospectively to analyze the correlation between amblyopia and various aspects of neurological development. RESULTS: A total of 128 preterm infants, 30 in the amblyopia risk group and 98 in the non-amblyopia risk group, were included in this study. Univariate analysis showed that the amblyopia risk group had lower birth weights, higher rates of asphyxia, preterm brain white matter injury, bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), sepsis during hospitalization, and higher rates of treatment with pulmonary surfactant (PS), blood transfusion, invasive ventilator, and levothyroxine. Logistic regression analysis showed that BPD in the neonatal period (odds ratio [OR] 8.355, 95% confidence interval [CI] 1.492, 46.786), brain white matter injury (OR 16.742, 95% CI 0.684, 409.804), treatment with levothyroxine (OR 2.859, 95% CI 0.946, 8.639), and use of an invasive ventilator (OR 2.983, 95% CI 0.942, 9.445) were independent risk factors for amblyopia at 12 months of corrected gestational age, while the administration of glucocorticoids (OR 0.055, 95% CI 0.004, 0.737) was a protective factor. Regarding neurodevelopmental assessment, the number of infants with lagging fine motor development was greater in the amblyopia risk group. CONCLUSION: The presence of BPD in the neonatal period, brain white matter damage in preterm infants, and use of levothyroxine and invasive ventilator were high risk factors for amblyopia. The use of glucocorticoids therapy was a protective factor. Children with risk of amblyopia had a higher rate of poor fine motor development.


Assuntos
Displasia Broncopulmonar , Recém-Nascido Prematuro , Lactente , Gravidez , Feminino , Criança , Recém-Nascido , Humanos , Pré-Escolar , Idade Gestacional , Incidência , Estudos Retrospectivos , Tiroxina , Displasia Broncopulmonar/epidemiologia , Fatores de Risco
16.
J Integr Neurosci ; 22(6): 157, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38176929

RESUMO

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by misfolding of α-synuclein. Clinical manifestations include slowly developing resting tremor, muscle rigidity, bradykinesia and abnormal gait. The pathological mechanisms underlying PD are complex and yet to be fully elucidated. Clinical studies suggest that the onset of gastrointestinal symptoms may precede motor symptoms in PD patients. The microbiota-gut-brain axis plays a bidirectional communication role between the enteric nervous system and the central nervous system. This bidirectional communication between the brain and gut is influenced by the neural, immune and endocrine systems related to the gut microbiome. A growing body of evidence indicates a strong link between dysregulation of the gut microbiota and PD. In this review, we present recent progress in understanding the relationship between the microbiota-gut-brain axis and PD. We focus on the role of the gut microbiota, the unique changes observed in the microbiome of PD patients, and the impact of these changes on the progression of PD. Finally, we evaluate the role of current treatment strategies for PD, including probiotics, fecal microbial transplants, dietary modifications, and related drug therapies.


Assuntos
Microbioma Gastrointestinal , Doença de Parkinson , Probióticos , Humanos , Doença de Parkinson/terapia , Eixo Encéfalo-Intestino , Encéfalo/patologia
17.
J Integr Plant Biol ; 65(9): 2122-2137, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37226855

RESUMO

Multicellular organisms such as plants contain various cell types with specialized functions. Analyzing the characteristics of each cell type reveals specific cell functions and enhances our understanding of organization and function at the organismal level. Guard cells (GCs) are specialized epidermal cells that regulate the movement of the stomata and gaseous exchange, and provide a model genetic system for analyzing cell fate, signaling, and function. Several proteomics analyses of GC are available, but these are limited in depth. Here we used enzymatic isolation and flow cytometry to enrich GC and mesophyll cell protoplasts and perform in-depth proteomics in these two major cell types in Arabidopsis leaves. We identified approximately 3,000 proteins not previously found in the GC proteome and more than 600 proteins that may be specific to GC. The depth of our proteomics enabled us to uncover a guard cell-specific kinase cascade whereby Raf15 and Snf1-related kinase2.6 (SnRK2.6)/OST1(open stomata 1) mediate abscisic acid (ABA)-induced stomatal closure. RAF15 directly phosphorylated SnRK2.6/OST1 at the conserved Ser175 residue in its activation loop and was sufficient to reactivate the inactive form of SnRK2.6/OST1. ABA-triggered SnRK2.6/OST1 activation and stomatal closure was impaired in raf15 mutants. We also showed enrichment of enzymes and flavone metabolism in GC, and consistent, dramatic accumulation of flavone metabolites. Our study answers the long-standing question of how ABA activates SnRK2.6/OST1 in GCs and represents a resource potentially providing further insights into the molecular basis of GC and mesophyll cell development, metabolism, structure, and function.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Proteínas Quinases/metabolismo , Proteômica , Arabidopsis/metabolismo , Ácido Abscísico/metabolismo , Estômatos de Plantas/fisiologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
18.
Genet Epidemiol ; 45(5): 455-470, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33645812

RESUMO

Genetic studies of two related survival outcomes of a pleiotropic gene are commonly encountered but statistical models to analyze them are rarely developed. To analyze sequencing data, we propose mixed effect Cox proportional hazard models by functional regressions to perform gene-based joint association analysis of two survival traits motivated by our ongoing real studies. These models extend fixed effect Cox models of univariate survival traits by incorporating variations and correlation of multivariate survival traits into the models. The associations between genetic variants and two survival traits are tested by likelihood ratio test statistics. Extensive simulation studies suggest that type I error rates are well controlled and power performances are stable. The proposed models are applied to analyze bivariate survival traits of left and right eyes in the age-related macular degeneration progression.


Assuntos
Oftalmopatias , Variação Genética , Oftalmopatias/genética , Estudos de Associação Genética , Humanos , Modelos Genéticos , Fenótipo
19.
Antimicrob Agents Chemother ; 66(6): e0218821, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35652644

RESUMO

Antibiotic resistance is the most important factor leading to failed Helicobacter pylori eradication therapy, and personalized treatment based on antibiotic susceptibility is becoming increasingly important. To strengthen the understanding of antibiotic genotypic resistance of H. pylori and identify new antibiotic resistance loci, in this study, we identified phenotypic resistance information for 60 clinical isolates and compared the concordance of phenotypic and genotypic resistance using whole-genome sequencing (WGS). Clarithromycin and levofloxacin genotypic resistance was in almost perfect concordance with phenotypic resistance, with kappa coefficients of 0.867 and 0.833, respectively. All strains with the R16H/C mutation and truncation in rdxA were metronidazole resistant, with 100% specificity. For other genes of concern, at least one phenotypically sensitive strain had a previous mutation related to antibiotic resistance. Moreover, we found that the A1378G mutation of HP0399 and the A149G mutation of FabH might contribute to tetracycline resistance and multidrug resistance, respectively. Overall, the inference of resistance to clarithromycin and levofloxacin from genotypic resistance is reliable, and WGS has been very helpful in discovering novel H. pylori resistance loci. In addition, WGS has also enhanced our study of strain lineages, providing new ways to understand resistance information and mechanisms.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Amoxicilina/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Claritromicina/farmacologia , Claritromicina/uso terapêutico , Farmacorresistência Bacteriana/genética , Genótipo , Infecções por Helicobacter/tratamento farmacológico , Humanos , Levofloxacino/farmacologia , Levofloxacino/uso terapêutico , Metronidazol/uso terapêutico , Testes de Sensibilidade Microbiana
20.
Opt Express ; 30(9): 14408-14420, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473184

RESUMO

Flexible control of light absorption within the lithography-free nanostructure is crucial for many polarization-dependent optical devices. Herein, we demonstrated that the lithography-free tunable absorber (LTA) can be realized by using two one-dimensional (1D) photonic crystals (PCs) consisting of an α-MoO3 layer at visible region. The two 1D PCs have different bulk band properties, and the topological interface state-induced light absorption enhancement of α-MoO3 can be realized as the α-MoO3 thin film is inserted at the interface between the two 1D PCs. The resonant cavity model is proposed to evaluate the anisotropic absorption performances of the LTA, and the results are in good agreement with those of the transfer matrix method (TMM). The absorption efficiency of the LTA can be tailored by the number of the period of the two PCs, and the larger peak absorption is the direct consequence of the larger field enhancement factor (FEF) within the α-MoO3 layer. In addition, near-perfect absorption can be achieved as the LTA is operated at the over-coupled resonance. By varying the polarization angle, the absorption channels can be selected and the reflection response can be effectively modulated due to the excellent in-plane anisotropy of α-MoO3.

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