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1.
BMC Cancer ; 24(1): 1100, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39232704

RESUMEN

BACKGROUND: Regulatory T (Treg) cells reportedly play crucial roles in tumor angiogenesis as well as antitumor immunity. In order to explore their therapeutic potential, we investigated the precise prognostic impact of Treg markers in endometrial carcinoma. METHODS: We performed multiplexed immunofluorescence and quantitative image analyses of CD25, FOXP3, CTLA4, and CD45RA in tumor specimens from 176 consecutive patients treated at our institution for primary endometrial carcinomas. Bioinformatics analyses were further conducted to corroborate the findings. RESULTS: High CD25+, FOXP3+, and CD25+FOXP3+CD45RA- stromal cell counts correlated with better overall survival (OS) (p = 0.00019, 0.028 and 0.0012) and MSI-high (p = 0.015, 0.016 and 0.047). High CD45RA+ stromal cell count was associated with superficial myometrial invasion (p = 0.0038). Bioinformatics survival analysis by Kaplan-Meier plotter showed that high CD25, FOXP3, CTLA4, and CD45RA mRNA expressions correlated with better OS (p = 0.046, 0.00042, 0.000044, and 0.0022). Univariate and multivariate analyses with various clinicopathologic prognostic factors indicated that high CD25+ or CD25+FOXP3+CD45RA- stromal cell count was significant and independent for favorable OS (p = 0.0053 and 0.0015). We subsequently analyzed the correlations between the multiplexed immunofluorescence results and treatment-free interval (TFI) after primary chemotherapy in recurrent cases, finding no significant associations. Further analysis revealed that high ratio of CD25+ : CD8+ cell count or CD25+FOXP3+CD45RA- : CD8+ cell count correlated with longer TFI (p = 0.021 and 0.021). CONCLUSION: The current observations suggest that the balance between CD25+ or CD25+FOXP3+CD45RA- cells and CD8+ cells, corresponding to promoting or inhibiting effect on tumor angiogenesis, affect tumor chemosensitivity leading to prognostic significance. CD25+FOXP3+CD45RA- effector Treg tumor infiltration may serve as a useful prognostic biomarker and a potential target for immunotherapeutic manipulation of tumor chemosensitivity by novel management for advanced/recurrent endometrial carcinomas.


Asunto(s)
Biomarcadores de Tumor , Neoplasias Endometriales , Factores de Transcripción Forkhead , Subunidad alfa del Receptor de Interleucina-2 , Antígenos Comunes de Leucocito , Linfocitos T Reguladores , Humanos , Femenino , Neoplasias Endometriales/inmunología , Neoplasias Endometriales/patología , Neoplasias Endometriales/mortalidad , Neoplasias Endometriales/genética , Factores de Transcripción Forkhead/metabolismo , Factores de Transcripción Forkhead/genética , Pronóstico , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Biomarcadores de Tumor/metabolismo , Antígenos Comunes de Leucocito/metabolismo , Persona de Mediana Edad , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Anciano , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Adulto , Estimación de Kaplan-Meier , Antígeno CTLA-4/metabolismo , Anciano de 80 o más Años
2.
EBioMedicine ; 108: 105343, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39276680

RESUMEN

BACKGROUND: Highly pathogenic respiratory RNA viruses such as SARS-CoV-2 and its associated syndrome COVID-19 pose a tremendous threat to the global public health. Innate immune responses to SARS-CoV-2 depend mainly upon the NF-κB-mediated inflammation. Identifying unknown host factors driving the NF-κB activation and inflammation is crucial for the development of immune intervention strategies. METHODS: Published single-cell RNA sequencing (scRNA-seq) data was used to analyze the differential transcriptome profiles of bronchoalveolar lavage (BAL) cells between healthy individuals (n = 27) and patients with severe COVID-19 (n = 21), as well as the differential transcriptome profiles of peripheral blood mononuclear cells (PBMCs) between healthy individuals (n = 22) and severely ill patients with COVID-19 (n = 45) or influenza (n = 16). Loss-of-function and gain-of-function assays were performed in diverse viruses-infected cells and male mice models to identify the role of TOMM34 in antiviral innate immunity. FINDINGS: TOMM34, together with a list of genes encoding pro-inflammatory cytokines and antiviral immune proteins, was transcriptionally upregulated in circulating monocytes, lung epithelium and innate immune cells from individuals with severe COVID-19 or influenza. Deficiency of TOMM34/Tomm34 significantly impaired the type I interferon responses and NF-κB-mediated inflammation in various human/murine cell lines, murine bone marrow-derived macrophages (BMDMs) and in vivo. Mechanistically, TOMM34 recruits TRAF6 to facilitate the K63-linked polyubiquitination of NEMO upon viral infection, thus promoting the downstream NF-κB activation. INTERPRETATION: In this study, viral induction of TOMM34 is positively correlated with the hyperinflammation in severely ill patients with COVID-19 and influenza. Our findings also highlight the physiological role of TOMM34 in the innate antiviral signallings. FUNDING: A full list of funding sources can be found in the acknowledgements section.

3.
Proc Natl Acad Sci U S A ; 121(35): e2400385121, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39167602

RESUMEN

Type 2 diabetes (T2D) is potentially linked to disordered tryptophan metabolism that attributes to the intricate interplay among diet, gut microbiota, and host physiology. However, underlying mechanisms are substantially unknown. Comparing the gut microbiome and metabolome differences in mice fed a normal diet (ND) and high-fat diet (HFD), we uncover that the gut microbiota-dependent tryptophan metabolite 5-hydroxyindole-3-acetic acid (5-HIAA) is present at lower concentrations in mice with versus without insulin resistance. We further demonstrate that the microbial transformation of tryptophan into 5-HIAA is mediated by Burkholderia spp. Additionally, we show that the administration of 5-HIAA improves glucose intolerance and obesity in HFD-fed mice, while preserving hepatic insulin sensitivity. Mechanistically, 5-HIAA promotes hepatic insulin signaling by directly activating AhR, which stimulates TSC2 transcription and thus inhibits mTORC1 signaling. Moreover, T2D patients exhibit decreased fecal levels of 5-HIAA. Our findings identify a noncanonical pathway of microbially producing 5-HIAA from tryptophan and indicate that 5-HIAA might alleviate the pathogenesis of T2D.


Asunto(s)
Dieta Alta en Grasa , Microbioma Gastrointestinal , Resistencia a la Insulina , Hígado , Diana Mecanicista del Complejo 1 de la Rapamicina , Receptores de Hidrocarburo de Aril , Transducción de Señal , Triptófano , Proteína 2 del Complejo de la Esclerosis Tuberosa , Animales , Dieta Alta en Grasa/efectos adversos , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Triptófano/metabolismo , Microbioma Gastrointestinal/efectos de los fármacos , Ratones , Receptores de Hidrocarburo de Aril/metabolismo , Hígado/metabolismo , Humanos , Proteína 2 del Complejo de la Esclerosis Tuberosa/metabolismo , Proteína 2 del Complejo de la Esclerosis Tuberosa/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/microbiología , Masculino , Ratones Endogámicos C57BL , Obesidad/metabolismo , Obesidad/microbiología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico
4.
World J Diabetes ; 15(6): 1070-1073, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38983803

RESUMEN

In this editorial, we commented on the article published in the recent issue of the World Journal of Diabetes. Diabetic cardiomyopathy (DCM) is characterized by myocardial fibrosis, ventricular hypertrophy and diastolic dysfunction in diabetic patients, which can cause heart failure and threaten the life of patients. The pathogenesis of DCM has not been fully clarified, and it may involve oxidative stress, inflammatory stimulation, apoptosis, and autophagy. There is lack of effective therapies for DCM in the clinical practice. Statins have been widely used in the clinical practice for years mainly to reduce cholesterol and stabilize arterial plaques, and exhibit definite cardiovascular protective effects. Studies have shown that statins also have anti-inflammatory and antioxidant effects. We were particularly concerned about the recent findings that atorvastatin alleviated myocardial fibrosis in db/db mice by regulating the antioxidant stress and anti-inflammatory effects of macrophage polarization on diabetic myocardium, and thereby improving DCM.

6.
World J Diabetes ; 15(5): 923-934, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38766441

RESUMEN

BACKGROUND: Diabetes foot is one of the most serious complications of diabetes and an important cause of death and disability, traditional treatment has poor efficacy and there is an urgent need to develop a practical treatment method. AIM: To investigate whether Huangma Ding or autologous platelet-rich gel (APG) treatment would benefit diabetic lower extremity arterial disease (LEAD) patients with foot ulcers. METHODS: A total of 155 diabetic LEAD patients with foot ulcers were enrolled and divided into three groups: Group A (62 patients; basal treatment), Group B (38 patients; basal treatment and APG), and Group C (55 patients; basal treatment and Huangma Ding). All patients underwent routine follow-up visits for six months. After follow-up, we calculated the changes in all variables from baseline and determined the differences between groups and the relationships between parameters. RESULTS: The infection status of the three groups before treatment was the same. Procalcitonin (PCT) improved after APG and Huangma Ding treatment more than after traditional treatment and was significantly greater in Group C than in Group B. Logistic regression analysis revealed that PCT was positively correlated with total amputation, primary amputation, and minor amputation rates. The ankle-brachial pressure and the transcutaneous oxygen pressure in Groups B and C were greater than those in Group A. The major amputation rate, minor amputation rate, and total amputation times in Groups B and C were lower than those in Group A. CONCLUSION: Our research indicated that diabetic foot ulcers (DFUs) lead to major amputation, minor amputation, and total amputation through local infection and poor microcirculation and macrocirculation. Huangma Ding and APG were effective attreating DFUs. The clinical efficacy of Huangma Ding was better than that of autologous platelet gel, which may be related to the better control of local infection by Huangma Ding. This finding suggested that in patients with DFUs combined with coinfection, controlling infection is as important as improving circulation.

7.
J Am Chem Soc ; 146(22): 14927-14934, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38767459

RESUMEN

Bicyclo[1.1.0]butane-containing compounds feature a unique chemical reactivity, trigger "strain-release" reaction cascades, and provide novel scaffolds with considerable utility in the drug discovery field. We report the synthesis of new bicyclo[1.1.0]butane-linked heterocycles by a nucleophilic addition of bicyclo[1.1.0]butyl anions to 8-isocyanatoquinoline, or, alternatively, iminium cations derived from quinolines and pyridines. The resulting bicyclo[1.1.0]butanes are converted with high regioselectivity to unprecedented bridged heterocycles in a rhodium(I)-catalyzed annulative rearrangement. The addition/rearrangement process tolerates a surprisingly large range of functional groups. Subsequent chemo- and stereoselective synthetic transformations of urea, alkene, cyclopropane, and aniline moieties of the 1-methylene-5-azacyclopropa[cd]indene scaffolds provide several additional new heterocyclic building blocks. X-ray structure-validated quantum mechanical DFT calculations of the reaction pathway indicate the intermediacy of rhodium carbenoid and metallocyclobutane species.

8.
Artículo en Inglés | MEDLINE | ID: mdl-38449110

RESUMEN

Epileptic seizures are unpredictable events caused by abnormal discharges of a patient's brain cells. Extensive research has been conducted to develop seizure prediction algorithms based on long-term continuous electroencephalogram (EEG) signals. This paper describes a patient-specific seizure prediction method that can serve as a basis for the design of lightweight, wearable and effective seizure-prediction devices. We aim to achieve two objectives using this method. The first aim is to extract robust feature representations from multichannel EEG signals, and the second aim is to reduce the number of channels used for prediction by selecting an optimal set of channels from multichannel EEG signals while ensuring good prediction performance. We design a seizure-prediction algorithm based on a vision transformer (ViT) model. The algorithm selects channels that play a key role in seizure prediction from 22 channels of EEG signals. First, we perform a time-frequency analysis of processed time-series signals to obtain EEG spectrograms. We then segment the spectrograms of multiple channels into many non-overlapping patches of the same size, which are input into the channel selection layer of the proposed model, named Sel-JPM-ViT, enabling it to select channels. Application of the Sel-JPM-ViT model to the Boston Children's Hospital-Massachusetts Institute of Technology scalp EEG dataset yields results using only three to six channels of EEG signals that are slightly better that the results obtained using 22 channels of EEG signals. Overall, the Sel-JPM-ViT model exhibits an average classification accuracy of 93.65%, an average sensitivity of 94.70% and an average specificity of 92.78%.

9.
Front Endocrinol (Lausanne) ; 15: 1368737, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38332891

Asunto(s)
Neoplasias , Humanos , Apoptosis
10.
Zhongguo Zhong Yao Za Zhi ; 49(1): 62-69, 2024 Jan.
Artículo en Chino | MEDLINE | ID: mdl-38403339

RESUMEN

The volatile oils are the effective components of Agastache rugosa, which are stored in the glandular scale. The leaves of pulegone-type A. rugosa were used as materials to observe the leaf morphology of A. rugosa at different growth stages, and the components of volatile oils in gland scales were detected by GC-MS. At the same time, qRT-PCR was used to determine the relative expression of key enzyme genes in the biosynthesis pathway of monoterpenes in volatile oils. The results showed that the density of A. rugosa glandular scale decreased first and then tended to be stable. With the growth of leaves, the relative content of pulegone decreased from 79.26% to 3.94%(89.97%-41.44%), while that of isomenthone increased from 2.43% to 77.87%(0.74%-51.01%), and the changes of other components were relatively insignificant. The correlation analysis between the relative content of monoterpenes and the relative expression levels of their key enzyme genes showed that there was a significant correlation between the relative content of menthone and isomenthone and the relative expression levels of pulegone reductase(PR)(r>0.6, P<0.01). To sum up, this study revealed the accumulation rules of the main components of the contents of the glandular scale of A. rugosa and the expression rules of the key enzyme genes for biosynthesis, which provided a scientific basis and data support for determining the appropriate harvesting period and quality control of the medicinal herbs. This study also initially revealed the biosynthesis mechanism of the monoterpenes mainly composed of pulegone and isomenthone in A. rugosa, laying a foundation for further research on the molecular mechanism of synthesis and accumulation of monoterpenes in A. rugosa.


Asunto(s)
Agastache , Monoterpenos Ciclohexánicos , Aceites Volátiles , Aceites Volátiles/análisis , Agastache/metabolismo , Monoterpenos/metabolismo
11.
World J Diabetes ; 14(11): 1585-1602, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38077806

RESUMEN

The complication of diabetes, which is known as diabetic foot ulcer (DFU), is a significant concern due to its association with high rates of disability and mortality. It not only severely affects patients' quality of life, but also imposes a substantial burden on the healthcare system. In spite of efforts made in clinical practice, treating DFU remains a challenging task. While mesenchymal stem cell (MSC) therapy has been extensively studied in treating DFU, the current efficacy of DFU healing using this method is still inadequate. However, in recent years, several MSCs-based drug delivery systems have emerged, which have shown to increase the efficacy of MSC therapy, especially in treating DFU. This review summarized the application of diverse MSCs-based drug delivery systems in treating DFU and suggested potential prospects for the future research.

12.
Zhongguo Zhong Yao Za Zhi ; 48(22): 6039-6050, 2023 Nov.
Artículo en Chino | MEDLINE | ID: mdl-38114210

RESUMEN

Terpenoids are important secondary metabolites of plants that possess both pharmacological activity and economic value. Terpene synthases(TPSs) are key enzymes in the synthesis process of terpenoids. In order to investigate the TPS gene family members and their potential functions in Schizonepeta tenuifolia, this study conducted a systematic analysis of the TPS gene family of S. tenuifolia based on the whole genome data of S. tenuifolia using bioinformatics methods. The results revealed 57 StTPS members identified from the genome database of S. tenuifolia. The StTPS family members encoded 285-819 amino acids, with protein molecular weights ranging from 32.75 to 94.11 kDa, all of which were hydrophilic proteins. The StTPS family members were mainly distributed in the cytoplasm and chloroplasts, exhibiting a random and uneven physical localization pattern. Phylogenetic analysis showed that the StTPS genes family were divided into six subgroups, mainly belonging to the TPS-a and TPS-b subfamilies. Promoter analysis predicted that the TPS gene family members could respond to various stressors such as light, abscisic acid, and methyl jasmonate(MeJA). Transcriptome data analysis revealed that most of the TPS genes were expressed in the roots of S. tenuifolia, and qRT-PCR analysis was conducted on genes with high expression in leaves and low expression in roots. Through the analysis of the TPS gene family of S. tenuifolia, this study identified StTPS5, StTPS18, StTPS32, and StTPS45 as potential genes involved in sesquiterpene synthesis of S. tenuifolia. StTPS45 was cloned for the construction of an prokaryotic expression vector, providing a reference for further investigation of the function and role of the TPS gene family in sesquiterpene synthesis.


Asunto(s)
Lamiaceae , Sesquiterpenos , Filogenia , Terpenos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Lamiaceae/genética
13.
Sci Bull (Beijing) ; 68(23): 3055-3079, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37926585

RESUMEN

The exponential growth of stationary energy storage systems (ESSs) and electric vehicles (EVs) necessitates a more profound understanding of the degradation behavior of lithium-ion batteries (LIBs), with specific emphasis on their lifetime. Accurately forecasting the lifetime of batteries under various working stresses aids in optimizing their operating conditions, prolonging their longevity, and ultimately minimizing the overall cost of the battery life cycle. Accelerated aging, as an efficient and economical method, can output sufficient cycling information in short time, which enables a rapid prediction of the lifetime of LIBs under various working stresses. Nevertheless, the prerequisite for accelerated aging-based battery lifetime prediction is the consistency of aging mechanisms. This review, by comprehensively summarizing the aging mechanisms of various components within LIBs and the battery degradation mechanisms under stress-accelerated conditions, provides a reference for evaluating the consistency of battery aging mechanisms. Furthermore, this paper introduces accelerated aging-based lifetime prediction models and offers constructive suggestions for future research on accelerated lifetime prediction of LIBs.

14.
Front Bioeng Biotechnol ; 11: 1283293, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37929200

RESUMEN

Introduction: When an intraocular lens (IOL) injector is inserted through a pre-cut corneal incision (e.g., an empirical size of 2.2 mm) during small incision cataract surgery, uncontrollable tearing to the corneal tissue may occur, which is highly associated with the incision shape, size, and location. The goal of this numerical study was to investigate the optimal incision scheme amongst three typical shapes, i.e., straight, frown, and chevron incisions using mechanical modeling and finite element analysis. Methods: Assuming that the damage is caused by the tissue fracture at the incision tips and is governed by the classical energy release rate (ERR) theory which compares the current ERR value subject to IOL injection and the material's intrinsic parameter, critical ERR G c. Results: It was found that for chevron incisions, the incision shape with an angle of 170° was superior which induced minimal ERR value, while for frown incisions, the shape with a central angle of 6° was optimal. Both chevron and frown incisions could allow a larger size of injector to inject through than a straight pre-cut. In particular, the frown incision performed the best due to its lowest corresponding ERR and easy operation. Discussion: It was also observed that regions where the embedded fibrils are more dispersed and exhibit high isotropy were more favorable. If necessary, the chevron incision was recommended to be more aligned with the direction exhibiting a larger modulus, for example, along the circumferential direction near the limbus. This study provides useful knowledge in operation design and a deep insight into mechanical damage to corneal wounds in small incision cataract surgery.

16.
Chem Sci ; 14(36): 9696-9703, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37736637

RESUMEN

Ring-opening of bicyclo[1.1.0]butanes (BCBs) is emerging as a powerful strategy for 1,3-difunctionalized cyclobutane synthesis. However, reported radical strain-release reactions are typically plagued with diastereoselectivity issues. Herein, an atom-economic protocol for the highly chemo- and diastereoselective polar strain-release ring-opening of BCBs with hydroxyarenes catalyzed by a π-acid catalyst AgBF4 has been developed. The use of readily available starting materials, low catalyst loading, high selectivity (up to >98 : 2 d.r.), a broad substrate scope, ease of scale-up, and versatile functionalizations of the cyclobutane products make this approach very attractive for the synthesis of 1,1,3-trisubstituted cyclobutanes. Moreover, control experiments and theoretical calculations were performed to illustrate the reaction mechanism and selectivity.

18.
Eur J Immunol ; 53(9): e2350501, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37369622

RESUMEN

Cholesterol plays essential roles in biological processes, including cell membrane stability and myelin formation. Cholesterol can be metabolized to oxysterols by enzymatic or nonenzymatic ways. Nonenzymatic cholesterol metabolites, also called cholesterol-autoxidation metabolites, are formed dependent on the oxidation of reactive oxygen species (ROS) such as OH• or reactive nitrogen species, such as ONOO- . Cholesterol-autoxidation metabolites are abundantly produced in diseases such as inflammatory bowel disease and atherosclerosis, which are associated with oxidative stress. Recent studies have shown that cholesterol-autoxidation metabolites can further regulate the immune system. Here, we review the literature and summarize how cholesterol-autoxidation metabolites, such as 25-hydroxycholesterol (25-OHC), 7α/ß-OHC, and 7-ketocholesterol, deal with the occurrence and development of infectious diseases through pattern recognition receptors, inflammasomes, ROS production, nuclear receptors, G-protein-coupled receptor 183, and lipid availability. In addition, we include the research regarding the roles of these metabolites in COVID-19 infection and discuss our viewpoints on the future research directions.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Humanos , Especies Reactivas de Oxígeno , Hidroxicolesteroles/metabolismo , Estrés Oxidativo , Oxidación-Reducción
19.
Viruses ; 15(6)2023 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-37376563

RESUMEN

Epizootic hemorrhagic disease (EHD) is an infectious viral disease caused by epizootic hemorrhagic disease virus (EHDV) and EHDV frequently circulates in wild and domestic ruminants. Sporadic outbreaks of EHD have caused thousands of deaths and stillbirths on cattle farms. However, not much is known about the circulating status of EHDV in Guangdong, southern China. To estimate the seroprevalence of EHDV in Guangdong province, 2886 cattle serum samples were collected from 2013 to 2017 and tested for antibodies against EHDV using a competitive ELISA. The overall seroprevalence of EHDV reached 57.87% and was highest in autumn (75.34%). A subset of positive samples were serotyped by a serum neutralization test, showing that EHDV serotypes 1 and 5-8 were circulating in Guangdong. In addition, EHDV prevalence always peaked in autumn, while eastern Guangdong had the highest EHDV seropositivity over the five-year period, displaying apparent temporal-spatial distribution of EHDV prevalence. A binary logistic model analysis indicated a significant association between cattle with BTV infections and seroprevalence of EHDV (OR = 1.70, p < 0.001). The co-infection of different serotypes of EHDV and BTV raises a high risk of potential genomic reassortment and is likely to pose a significant threat to cattle, thus urging more surveillance to monitor their circulating dynamics in China.


Asunto(s)
Virus de la Lengua Azul , Enfermedades de los Bovinos , Virus de la Enfermedad Hemorrágica Epizoótica , Infecciones por Reoviridae , Animales , Bovinos , Infecciones por Reoviridae/epidemiología , Infecciones por Reoviridae/veterinaria , Virus de la Enfermedad Hemorrágica Epizoótica/genética , Estudios Seroepidemiológicos , Granjas , Anticuerpos Antivirales
20.
Opt Express ; 31(10): 16929-16938, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37157761

RESUMEN

As a photonic-based microwave signal generation method, the optoelectronic oscillator (OEO) has the potential of meeting the increasing demand of practical applications for high frequency, broadband tunability and ultra-low phase noise. However, conventional OEO systems implemented with discrete optoelectronic devices have a bulky size and low reliability, which extremely limits their practical applications. In this paper, a hybrid-integrated wideband tunable OEO with low phase noise is proposed and experimentally demonstrated. The proposed hybrid integrated OEO achieves a high integration level by first integrating a laser chip with a silicon photonic chip, and then connecting the silicon photonic chip with electronic chips through wire-bonding to microstrip lines. A compact fiber ring and an yttrium iron garnet filter are also adopted for high-Q factor and frequency tuning, respectively. The integrated OEO exhibits a low phase noise of -128.04 dBc/Hz @ 10 kHz for an oscillation frequency of 10 GHz. A wideband tuning range from 3 GHz to 18 GHz is also obtained, covering the entire C, X, and Ku bands. Our work demonstrates an effective way to achieve compact high-performance OEO based on hybrid integration, and has great potential in a wide range of applications such as modern radar, wireless communication, and electronic warfare systems.

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