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3.
Aging Cell ; : e14266, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38958042

ABSTRACT

Age-related chronic inflammatory lung diseases impose a threat on public health, including idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD). However, their etiology and potential targets have not been clarified. We performed genome-wide meta-analysis for IPF with the largest sample size (2883 cases and 741,929 controls) and leveraged the summary statistics of COPD (17,547 cases and 617,598 controls). Transcriptome-wide and proteome-wide Mendelian randomization (MR) designs, together with genetic colocalization, were implemented to find robust targets. The mediation effect was assessed using leukocyte telomere length (LTL). The single-cell transcriptome analysis was performed to link targets with cell types. Individual-level data from UK Biobank (UKB) were used to validate our findings. Sixteen genetically predicted plasma proteins were causally associated with the risk of IPF and 6 proteins were causally associated with COPD. Therein, genetically-elevated plasma level of SCARF2 protein should reduce the risk of both IPF (odds ratio, OR = 0.9974 [0.9970, 0.9978]) and COPD (OR = 0.7431 [0.6253, 0.8831]) and such effects were not mediated by LTL. Genetic colocalization further corroborated these MR results of SCARF2. The transcriptome-wide MR confirmed that higher expression level of SCARF2 was associated with a reduced risk of both. However, the single-cell RNA analysis indicated that SCARF2 expression level was only relatively lower in epithelial cells of COPD lung tissue compared to normal lung tissue. UKB data implicated an inverse association of serum SCARF2 protein with COPD (hazard ratio, HR = 1.215 [1.106, 1.335]). The SCARF2 gene should be a novel target for COP.

4.
Phys Rev Lett ; 132(24): 246401, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38949361

ABSTRACT

Twisted bilayer graphene (TBG) can host the moiré energy flat bands with twofold degeneracy serving as a fruitful playground for strong correlations and topological phases. However, the number of degeneracy is not limited to two. Introducing a spatially alternative magnetic field, we report that the induced magnetic phase becomes an additional controllable parameter and leads to an undiscovered generation of fourfold degenerate flat bands. This emergence stems from the band inversion at the Γ point near the Fermi level with a variation of both twisted angle and magnetic phase. We present the conditions for the emergence of multifold degenerate flat bands, which are associated with the eigenvalue degeneracy of a Birman-Schwinger operator. Using holomorphic functions, which explain the origin of the double flat bands in the conventional TBG, we can generate analytical wave functions in the magnetic TBG to show absolute flatness with fourfold degeneracy. Moreover, we identify an orbital-related intervalley coherent state as the many-body ground state at charge neutrality. In contrast, the conventional TBG has only two moiré energy flat bands, and the highly degenerate flat bands with additional orbital channels in this magnetic platform might bring richer correlation physics.

5.
J Cancer ; 15(13): 4313-4327, 2024.
Article in English | MEDLINE | ID: mdl-38947397

ABSTRACT

Aquaporin 5 (AQP5) has been shown to have a pro-carcinogenic effect in numerous types of malignancies. This research intends to investigate the role and the molecular mechanism of AQP5 on enriched gastric cancer stem cells (GCSCs). Methods: Immunohistochemistry, western blot (WB), and RT-qPCR techniques were employed to identify the presence of AQP5 in gastric cancer (GC) and the neighboring paracancerous tissues. Additionally, a statistical analysis was conducted to determine the correlation between AQP5 expression and the pathological and histological parameters. Furthermore, the study aimed to assess the predictive value of AQP5 expression in long-term survival after GC surgery. GCSCs were enriched using the serum-free culture method. The expression of AQP5 in enriched GCSCs was explored using RT-qPCR and WB. Plate cloning, transwell, WB, RT-qPCR, and the sphere-forming assay were utilized to monitor the proliferation, migration, and self-renewal capability of GCSCs after AQP5 knockdown. WB and Immunofluorescence for Detecting the Effect of AQP5 on Autophagy. WB, RT-qPCR, and other experiments were used for in-depth investigation of the potential molecular regulatory mechanism of AQP5 in GC. Results: AQP5 was highly expressed in GC tissues and GC cells, and overexpression of AQP5 was associated with lymph node metastasis, increased tumor size, and low 5-year postoperative survival in GC patients; other studies have shown that the AQP5 was highly expressed in GCSCs. Knockdown of AQP5 suppressed tumorigenesis in vivo and inhibited the proliferative, migratory, and self-renewal capability of GCSCs. It was also found that AQP5 could activate the autophagy phenomenon of GCSCs, and mechanistically, we found that AQP5 could regulate TRPV4 to affect the self-renewal ability of GCSCs. Conclusion: AQP5 can be further explored for GC therapy, as it has shown a significant impact on the self-renewal capability of GCSCs, which prevents GC progression.

6.
Theranostics ; 14(9): 3565-3582, 2024.
Article in English | MEDLINE | ID: mdl-38948069

ABSTRACT

Cancer therapy has moved from single agents to more mechanism-based targeted approaches. In recent years, the combination of HDAC inhibitors and other anticancer chemicals has produced exciting progress in cancer treatment. Herein, we developed a novel prodrug via the ligation of dichloroacetate to selenium-containing potent HDAC inhibitors. The effect and mechanism of this compound in the treatment of prostate cancer were also studied. Methods: The concerned prodrug SeSA-DCA was designed and synthesized under mild conditions. This compound's preclinical studies, including the pharmacokinetics, cell toxicity, and anti-tumor effect on prostate cancer cell lines, were thoroughly investigated, and its possible synergistic mechanism was also explored and discussed. Results: SeSA-DCA showed good stability in physiological conditions and could be rapidly decomposed into DCA and selenium analog of SAHA (SeSAHA) in the tumor microenvironment. CCK-8 experiments identified that SeSA-DCA could effectively inhibit the proliferation of a variety of tumor cell lines, especially in prostate cancer. In further studies, we found that SeSA-DCA could also inhibit the metastasis of prostate cancer cell lines and promote cell apoptosis. At the animal level, oral administration of SeSA-DCA led to significant tumor regression without obvious toxicity. Moreover, as a bimolecular coupling compound, SeSA-DCA exhibited vastly superior efficacy than the mixture with equimolar SeSAHA and DCA both in vitro and in vivo. Our findings provide an important theoretical basis for clinical prostate cancer treatment. Conclusions: Our in vivo and in vitro results showed that SeSA-DCA is a highly effective anti-tumor compound for PCa. It can effectively induce cell cycle arrest and growth suppression and inhibit the migration and metastasis of PCa cell lines compared with monotherapy. SeSA-DCA's ability to decrease the growth of xenografts is a little better than that of docetaxel without any apparent signs of toxicity. Our findings provide an important theoretical basis for clinical prostate cancer treatment.


Subject(s)
Apoptosis , Cell Cycle Checkpoints , Histone Deacetylase Inhibitors , Prostatic Neoplasms , cdc25 Phosphatases , Male , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/pathology , Humans , Animals , Apoptosis/drug effects , Histone Deacetylase Inhibitors/pharmacology , Histone Deacetylase Inhibitors/therapeutic use , Histone Deacetylase Inhibitors/chemistry , Cell Line, Tumor , Cell Cycle Checkpoints/drug effects , cdc25 Phosphatases/metabolism , Mice , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Cell Proliferation/drug effects , Mice, Nude , Selenium/pharmacology , Selenium/chemistry , Selenium/therapeutic use , Xenograft Model Antitumor Assays , Prodrugs/pharmacology , Prodrugs/chemistry , Mice, Inbred BALB C
7.
Asian J Pharm Sci ; 19(3): 100910, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38948397

ABSTRACT

The early diagnosis of cancer is vital for effective treatment and improved prognosis. Tumor biomarkers, which can be used for the early diagnosis, treatment, and prognostic evaluation of cancer, have emerged as a topic of intense research interest in recent years. Nucleic acid, as a type of tumor biomarker, contains vital genetic information, which is of great significance for the occurrence and development of cancer. Currently, living cell nucleic acid probes, which enable the in situ imaging and dynamic monitoring of nucleic acids, have become a rapidly developing field. This review focuses on living cell nucleic acid probes that can be used for the early diagnosis of tumors. We describe the fundamental design of the probe in terms of three units and focus on the roles of different nanomaterials in probe delivery.

9.
Front Endocrinol (Lausanne) ; 15: 1379398, 2024.
Article in English | MEDLINE | ID: mdl-38957444

ABSTRACT

Background: Diabetic gastroparesis is a common complication in patient with diabetes. Dietary intervention has been widely used in the treatment of diabetic gastroparesis. The aim of this study is to evaluate the role of diet in the treatment of diabetic gastroparesis. Methods: This systematic review was conducted a comprehensive search of randomized controlled trials using dietary interventions for the treatment of diabetic gastroparesis up to 9 November 2023. The primary outcomes were gastric emptying time and clinical effect, while fasting blood glucose, 2-hour postprandial blood glucose and glycosylated hemoglobin were secondary outcomes. Data analysis was performed using RevMan 5.4 software, and publication bias test was performed using Stata 15.1 software. Results: A total of 15 randomized controlled trials involving 1106 participants were included in this review. The results showed that patients with diabetic gastroparesis benefit from dietary interventions (whether personalized dietary care alone or personalized dietary care+routine dietary care). Compared with routine dietary care, personalized dietary care and personalized dietary care+routine dietary care can shorten the gastric emptying time, improve clinical efficacy, and reduce the level of fasting blood glucose, 2-hour postprandial blood glucose and glycosylated hemoglobin. Conclusions: Limited evidence suggests that dietary intervention can promote gastric emptying and stabilize blood glucose control in patients with diabetic gastroparesis. Dietary intervention has unique potential in the treatment of diabetic gastroparesis, and more high-quality randomized controlled trials are needed to further validate our research results. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023481621.


Subject(s)
Gastroparesis , Humans , Gastroparesis/diet therapy , Gastroparesis/therapy , Gastroparesis/etiology , Gastric Emptying , Blood Glucose/metabolism , Diabetes Complications/diet therapy , Randomized Controlled Trials as Topic , Treatment Outcome , Diabetes Mellitus/diet therapy
10.
Immunol Lett ; : 106890, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38959983

ABSTRACT

BACKGROUND: Autoimmune thyroiditis (AITD) is an organ-specific autoimmune disease. Substantial evidence suggests that Vitamin D (VitD) deficiency is closely associated with an increased risk of AITD. However, the effects of VitD3 on immune cells, especially Th17/Treg cell subsets, and the underlying molecular mechanism in AITD have not yet been investigated. METHODS: An experimental autoimmune thyroiditis (EAT) mouse model was established with a high-iodine diet. After 8 weeks, thyroid injury was assessed using hematoxylin and eosin (H&E) staining. ELISA was employed to measure serum levels of thyroxine (T3 and T4), thyroid autoimmune antibodies (Tg-Ab and TPO-Ab), and inflammatory cytokines. Flow cytometry and multiplex fluorescence immunohistochemical (mIHC) assays were used to analyze Th17/Treg cell subsets. The CCK-8 and flow cytometry assays were used to determine cell viability and apoptosis. RESULTS: Administration of VitD3 reduced thyroid follicle destruction, decreased lymphocyte infiltration, and lowered T3, T4, Tg-Ab, and TPO-Ab serum levels in EAT mice. VitD3 treatment also reduced the frequency of Th17 cells while promoting the Treg cell subset both in the thyroid tissue and in the splenocytes cultured in vitro. Furthermore, VitD3 administration suppressed the production of inflammatory cytokines in EAT mice. VitD3 was also found to regulate Treg cells' differentiation, viability, and apoptosis. Mechanistically, we discovered that VitD3 treatment upregulated YAP expression and activated the JAK/STAT pathway. Rescue assays confirmed that depletion of YAP counteracted the effects of VitD3 on Treg cell differentiation and function. CONCLUSION: Vitamin D3 attenuates AITD by modulating Th17/Treg cell balance via regulating the YAP/JAK1/STAT1 axis.

11.
Angew Chem Int Ed Engl ; : e202409328, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38958874

ABSTRACT

Proton supply is as critical as O2 activation for artificial photosynthesis of H2O2 via two-electron oxygen reduction reaction (2e- ORR). However, proton release via water dissociation is frequently hindered because of the sluggish water oxidation reaction (WOR), extremely limiting the efficiency of photocatalytic H2O2 production. To tackle this challenge, carboxyl-enriched supramolecular polymer (perylene tetracarboxylic acid - PTCA) is elaborately prepared by molecular self-assembly for overall photosynthesis of H2O2. Interestingly, the interconversion between carboxyl as Brønsted acid and its conjugated base realizes rapid proton circulation. Through this efficient tandem proton transfer process, the spatial effect of photocatalytic reduction and oxidation reaction is greatly enhanced with reduced reaction barrier. This significantly facilitates 2e- photocatalytic ORR to synthesize H2O2 and in the meanwhile promotes 4e- photocatalytic WOR to evolve O2. Consequently, the as-developed PTCA exhibits a remarkable H2O2 yield of 185.6 µM h-1 in pure water and air atmosphere under visible light illumination. More impressively, an appreciable H2O2 yield of 78.6 µM h-1 can be well maintained in an anaerobic system owing to in-situ O2 generation by 4e- photocatalytic WOR. Our study presents a novel concept for artificial photosynthesis of H2O2 via constructing efficient proton transfer pathway to enable rapid proton circulation.

12.
J Cancer Res Clin Oncol ; 150(6): 300, 2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38850373

ABSTRACT

PURPOSE: Tertiary lymphoid structures (TLSs) and CD8 + T-cells are potential prognostic indicators for pancreatic ductal adenocarcinoma (PDAC). We established a novel scoring system for evaluating the risk for PDAC based on TLS- and CD8 + T-cell-related genes. METHODS: We analyzed single-cell sequence data from PDAC patients in the Genome Sequence Archive. Bioinformatics and machine algorithms established and validated a scoring method (T-C score) based on PDAC survival-related genes highly expressed in TLSs and CD8 + T-cells. Patients were stratified into the low- and high-T-C score groups. Differences in survival, pathway enrichment, mutation status, immune cell infiltration, expression of immune checkpoint-associated genes, tumor stemness, and response to antitumor therapy were compared through computer simulation methods. RESULTS: Overall survival differed significantly between the training and validation cohorts' low- and high-T-C score groups. The low-T-C score group correlated with lower tumor mutation burden and lower levels of tumor stemness compared with the high-T-C score group. Patients with lower T-C scores exhibited advantages in immunotherapeutic responses and might be more sensitive to the chemotherapeutic regimen and multi-kinase inhibitors. CONCLUSION: The T-C score could serve as an effective model for predicting the survival and therapeutic responses of patients with PDAC.


Subject(s)
CD8-Positive T-Lymphocytes , Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Tertiary Lymphoid Structures , Humans , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/immunology , Carcinoma, Pancreatic Ductal/pathology , Prognosis , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/immunology , Pancreatic Neoplasms/pathology , CD8-Positive T-Lymphocytes/immunology , Tertiary Lymphoid Structures/genetics , Tertiary Lymphoid Structures/immunology , Tertiary Lymphoid Structures/pathology , Genomics/methods , Male , Female , Biomarkers, Tumor/genetics , Middle Aged , Aged
13.
Heliyon ; 10(11): e32187, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38868075

ABSTRACT

PAXLOVID™ (Co-packaging of Nirmatrelvir with Ritonavir) has been approved for the treatment of Coronavirus Disease 2019 (COVID-19). The goal of the experiment was to create an accurate and straightforward analytical method using ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) to simultaneously quantify nirmatrelvir and ritonavir in rat plasma, and to investigate the pharmacokinetic profiles of these drugs in rats. After protein precipitation using acetonitrile, nirmatrelvir, ritonavir, and the internal standard (IS) lopinavir were separated using ultra performance liquid chromatography (UPLC). This separation was achieved with a mobile phase composed of acetonitrile and an aqueous solution of 0.1% formic acid, using a reversed-phase column with a binary gradient elution. Using multiple reaction monitoring (MRM) technology, the analytes were detected in the positive electrospray ionization mode. Favorable linearity was observed in the calibration range of 2.0-10000 ng/mL for nirmatrelvir and 1.0-5000 ng/mL for ritonavir, respectively, within plasma samples. The lower limits of quantification (LLOQ) attained were 2.0 ng/mL for nirmatrelvir and 1.0 ng/mL for ritonavir, respectively. Both drugs demonstrated inter-day and intra-day precision below 15%, with accuracies ranging from -7.6% to 13.2%. Analytes were extracted with recoveries higher than 90.7% and without significant matrix effects. Likewise, the stability was found to meet the requirements of the analytical method under different conditions. This UPLC-MS/MS method, characterized by enabling accurate and precise quantification of nirmatrelvir and ritonavir in plasma, was effectively utilized for in vivo pharmacokinetic studies in rats.

14.
J Biomed Inform ; 156: 104672, 2024 Jun 09.
Article in English | MEDLINE | ID: mdl-38857738

ABSTRACT

In drug development and clinical application, drug-drug interaction (DDI) prediction is crucial for patient safety and therapeutic efficacy. However, traditional methods for DDI prediction often overlook the structural features of drugs and the complex interrelationships between them, which affect the accuracy and interpretability of the model. In this paper, a novel dual-view DDI prediction framework, DAS-DDI is proposed. Firstly, a drug association network is constructed based on similarity information among drugs, which could provide rich context information for DDI prediction. Subsequently, a novel drug substructure extraction method is proposed, which could update the features of nodes and chemical bonds simultaneously, improving the comprehensiveness of the feature. Furthermore, an attention mechanism is employed to fuse multiple drug embeddings from different views dynamically, enhancing the discriminative ability of the model in handling multi-view data. Comparative experiments on three public datasets demonstrate the superiority of DAS-DDI compared with other state-of-the-art models under two scenarios.

15.
Nat Commun ; 15(1): 5054, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38871698

ABSTRACT

Photoluminescence (PL) colour-changing materials in response to photostimulus play an increasingly significant role in intelligent applications for their programmability. Nevertheless, current research mainly focuses on photochemical processes, with less attention to PL transformation through uniform aggregation mode adjustment. Here we show photochromic luminescence in organic crystals (e.g. dimethyl terephthalate) with PL varying from dark blue to purple, then to bright orange-red, and finally to red. This change is attributed to the emergence of clusters with red emission, which is barely achieved in single-benzene-based structures, thanks to the subtle molecular rearrangements prompted by light. Crucial to this process are the through-space electron interactions among molecules and moderate short contacts between ester groups. The irradiated crystals exhibit reversible PL transformation upon sufficient relaxation, showing promising applications in information storage and smart optoelectronic devices. This research contributes to the development of smart photochromic luminescent materials with significant PL colour transformations through molecular rearrangement.

16.
Int J Biochem Cell Biol ; : 106610, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38879152

ABSTRACT

Colorectal cancer (CRC) is the third most common type of cancer in the world. It is characterized by complex crosstalk between various signaling pathways, as a result of which it is highly challenging to identify optimal therapeutic targets and design treatment strategies. In this study, we tested the effect of 700 compounds on the CRC cell line HT-29 by using the sulforhodamine B assay and screened out 17 compounds that exhibited high toxicity (indicated by an inhibition rate of ≥75% when applied at a concentration of 10µM) against the HT-29 cell line. Next, we investigated the mechanisms underlying the effects of these 17 highly toxic compounds. The results of ferroptosis analysis and electron microscopy showed that compounds 575 and 578 were able to significantly reverse RSL3-induced increase in ferroptosis, while compound 580 had a less pronounced ferroptosis-regulating effect. In subsequent experiments, western blotting showed that compounds 575, 578, and 580, which belong to a class of meroterpene-like compounds that affect ferroptosis, do not induce autophagy or apoptosis in the CRC cell line. Instead, Fe2+ chelation experiments showed that these three compounds can serve as iron chelators by chelating Fe2+ at a 1:1 (chelator: Fe2+) ratio. Specifically, the aldehyde and hydroxyl groups of the benzene ring in these compounds may chelate Fe2+, thus reducing Fe2+ levels in cells and inhibiting ferroptosis. These results indicate that these novel meroterpene-like compounds are potential therapeutic small-molecule candidates for targeting ferroptosis in tumors.

17.
Front Physiol ; 15: 1243629, 2024.
Article in English | MEDLINE | ID: mdl-38883186

ABSTRACT

Cu is an essential micronutrient for various physiological processes in almost all human cell types. Given the critical role of Cu in a wide range of cellular processes, the local concentrations of Cu and the cellular distribution of Cu transporter proteins in the lung are essential for maintaining a steady-state internal environment. Dysfunctional Cu metabolism or regulatory pathways can lead to an imbalance in Cu homeostasis in the lungs, affecting both acute and chronic pathological processes. Recent studies have identified a new form of Cu-dependent cell death called cuproptosis, which has generated renewed interest in the role of Cu homeostasis in diseases. Cuproptosis differs from other known cell death pathways. This occurs through the direct binding of Cu ions to lipoylated components of the tricarboxylic acid cycle during mitochondrial respiration, leading to the aggregation of lipoylated proteins and the subsequent downregulation of Fe-S cluster proteins, which causes toxic stress to the proteins and ultimately leads to cell death. Here, we discuss the impact of dysregulated Cu homeostasis on the pathogenesis of various respiratory diseases, including asthma, chronic obstructive pulmonary disease, idiopathic interstitial fibrosis, and lung cancer. We also discuss the therapeutic potential of targeting Cu. This study highlights the intricate interplay between copper, cellular processes, and respiratory health. Copper, while essential, must be carefully regulated to maintain the delicate balance between necessity and toxicity in living organisms. This review highlights the need to further investigate the precise mechanisms of copper interactions with infections and immune inflammation in the context of respiratory diseases and explore the potential of therapeutic strategies for copper, cuproptosis, and other related effects.

18.
Front Nutr ; 11: 1273851, 2024.
Article in English | MEDLINE | ID: mdl-38883859

ABSTRACT

Background: Although social capital has been linked to dietary intake particularly in disadvantaged populations, little is known about the mechanisms. This study aimed to investigate whether social support (SS) and nutrition knowledge (NK) mediate the association between social capital and healthy eating habits. Methods: A probability sample of two ethnic minority groups in Yunnan Province, Southwest China were included (n = 1,033, mean age 47.5 ± 14.7 years). Bonding and bridging social capital (BOC and BRC) were assessed with the Personal Social Capital Scale (PSCS-16). Dietary data were evaluated with the Chinese Healthy Eating Index (CHEI), a measure of diet quality which reflects adherence to the Chinese Dietary Guidelines. NK and SS were measured with a validated questionnaire and scale, respectively. Structural Equation Modeling was used to calculate the direct, indirect and total effects of social capital on CHEI scores. Results: The mean score of CHEI was 57.4 ± 9.8, which was significantly lower in men and older people. Low adherence to dietary guidelines were to observed in the consumption of dairy, beans, nuts, animal-source food vegetables and fruits. BOC and BRC were positively associated with CHEI score (ß = 0.37 and 0.38, all p < 0.05). Social support and nutrition knowledge mediated 45.9 and 39.5% of the total effect of social capital on CHEI score, respectively. Conclusion: Social capital appears to enhance adherence to dietary guidelines by improving nutrition knowledge and social support. Nutrition promotion programs therefore should consider incorporating strategies that foster social capital development, particularly in disadvantaged populations.

19.
Opt Lett ; 49(12): 3492-3495, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38875653

ABSTRACT

In this paper, a compact silicon-based photonic microwave frequency downconverter with broadband operation capability and continuous phase shift tunability is proposed and experimentally demonstrated. The photonic converter mainly comprises two micro-ring modulators (MRMs) connected in parallel and a cascaded resonator-based optical bandpass filter (OBPF) whose size is merely 200 × 700 µm2. In the proposed device, a radio frequency (RF) signal and a local oscillator (LO) signal drive the two MRMs for realizing the electro-optic conversion. The OBPF is utilized for selecting the first-order sidebands of both RF and LO signals. By manipulating the phase difference between the RF and LO optical sidebands through thermal-optic effect, the phase of the obtained intermediate frequency (IF) signal from a photodiode can be tuned continuously. Experimental results demonstrate a 137° phase shift while the RF signals of 20 and 40 GHz are downconverted to an IF signal of 0.4 GHz, which indicates the photonic microwave downconverter can be used in the Ka-band phased-array receiver.

20.
New Phytol ; 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38877698

ABSTRACT

Phytophthora parasitica causes diseases on a broad range of host plants. It secretes numerous effectors to suppress plant immunity. However, only a few virulence effectors in P. parasitica have been characterized. Here, we highlight that PpE18, a conserved RXLR effector in P. parasitica, was a virulence factor and suppresses Nicotiana benthamiana immunity. Utilizing luciferase complementation, co-immunoprecipitation, and GST pull-down assays, we determined that PpE18 targeted NbAPX3-1, a peroxisome membrane-associated ascorbate peroxidase with reactive oxygen species (ROS)-scavenging activity and positively regulates plant immunity in N. benthamiana. We show that the ROS-scavenging activity of NbAPX3-1 was critical for its immune function and was hindered by the binding of PpE18. The interaction between PpE18 and NbAPX3-1 resulted in an elevation of ROS levels in the peroxisome. Moreover, we discovered that the ankyrin repeat-containing protein NbANKr2 acted as a positive immune regulator, interacting with both NbAPX3-1 and PpE18. NbANKr2 was required for NbAPX3-1-mediated disease resistance. PpE18 competitively interfered with the interaction between NbAPX3-1 and NbANKr2, thereby weakening plant resistance. Our results reveal an effective counter-defense mechanism by which P. parasitica employed effector PpE18 to suppress host cellular defense, by suppressing biochemical activity and disturbing immune function of NbAPX3-1 during infection.

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