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1.
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.

2.
Purinergic Signal ; 19(1): 315-327, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36121551

RESUMEN

Growing evidence reveals that microorganisms in the gut are linked to metabolic health and disease risk in human beings to a considerable extent. The focus of research at this stage must tend to focus on cause-and-effect studies. In addition to being a component of DNA and RNA, purine metabolites can be involved in purine signalling in the body as chemical messengers. Abnormalities in purinergic signalling may lead to neuropathy, rheumatic immune diseases, inflammation, tumors, and a wide range of other diseases. It has proved that gut microbes are involved in purinergic signalling. The relationship between these gut-derived purinergic signalling molecules and host metabolism may be one of the important clues to our understanding of the mechanisms by which the microbiota affects host metabolism.


Asunto(s)
Microbioma Gastrointestinal , Humanos , Inflamación , Transducción de Señal
3.
Neurol Sci ; 44(3): 881-887, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36383265

RESUMEN

BACKGROUND: Insulin-like growth factor 1 (IGF-1) and epidermal growth factor (EGF) exert neuroprotective effects in Parkinson's disease (PD). To date, studies on the relationships between serum IGF-1 and EGF levels and nonmotor symptoms in PD patients have been rare. METHODS: A Siemens automatic chemical analyzer was used to determine serum IGF-1 levels, and enzyme-linked immunosorbent assay was used to detect serum EGF levels in 100 healthy controls and 100 PD patients, including those in the early (n = 49) and middle-late (n = 51) stage of the disease. Evaluation of motor symptoms and nonmotor symptoms in PD patients was assessed by the associated scales. RESULTS: Serum IGF-1 and EGF levels were higher in PD patients than in healthy controls, and serum IGF-1 and EGF levels were higher in early stage PD patients than in middle-late stage PD patients. Serum IGF-1 levels were significantly negatively correlated with anxiety, depression, and cognitive dysfunction; serum EGF levels were significantly negatively correlated with cognitive dysfunction. Combining IGF-1 and EGF in the diagnosis of PD was more valuable than using a single factor in the diagnosis. CONCLUSIONS: This study shows that serum IGF-1 levels were correlated with the nonmotor symptoms of anxiety, depression, and cognitive dysfunction and that EGF levels were correlated with cognitive dysfunction. The combination of IGF-1 and EGF increased the value for a PD diagnosis. This is the first report of the simultaneous detection of IGF-1 and EGF levels to explore the correlation with nonmotor symptoms of PD.


Asunto(s)
Disfunción Cognitiva , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/diagnóstico , Factor de Crecimiento Epidérmico , Factor I del Crecimiento Similar a la Insulina/metabolismo , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Cognición
4.
Eur J Neurosci ; 55(6): 1471-1482, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35243702

RESUMEN

Obstructive sleep apnoea syndrome (OSAS) is a potentially severe sleep disorder characterized by intermittent hypoxia, and there is growing evidence that OSAS can lead to cognitive decline. Extracellular signal-regulated protein kinase 1/2 (ERK1/2) plays a key role in synaptic plasticity. We established CIH model in male SD rats and examined their expression of p-ERK1/2 and PSD-95, as well as in CIH group; the effect of SL327 on the expression of p-ERK1/2 and PSD-95 in hippocampus of CIH model rats was observed by pretreating the experimental rats with SL327 during peak time of p-ERK1/2 expression. Mean oxygen saturation in the tail artery was lower in the CIH group. CIH groups exhibited increased escape latencies in the navigation test and decreased numbers of platform crossings in the space exploration test. Reduced volume, irregular structure, deepened cytoplasmic eosinophilic staining in the cytoplasm and decreased nuclear size were found in hippocampal neurons in the 28-d CIH and 28-d CIH + SL327 group. The hippocampus of CIH rats' p-ERK expressions gradually increased with prolonged CIH exposure but decreased after SL327 treatment. Moreover, PSD-95 expressions gradually reduced in the 14-d CIH, 21-d CIH and 28-d CIH groups but increased in the SL327-treated group. The SL327 intervention decreased p-ERK1/2 expression, increased PSD-95 expression and improved cognitive function in CIH rats. The present findings provide some insights into the mechanisms underlying OSAS-associated cognitive impairment.


Asunto(s)
Sistema de Señalización de MAP Quinasas , Apnea Obstructiva del Sueño , Animales , Cognición , Homólogo 4 de la Proteína Discs Large/metabolismo , Hipocampo/metabolismo , Hipoxia/metabolismo , Masculino , Proteína Quinasa 1 Activada por Mitógenos , Ratas , Ratas Sprague-Dawley , Apnea Obstructiva del Sueño/metabolismo
5.
Neurol Sci ; 43(3): 1747-1754, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34405296

RESUMEN

BACKGROUND: Uric acid (UA) plays a protective role in Parkinson's disease (PD). To date, studies on the relationship between serum UA levels and nonmotor symptoms and brain gray matter volume in PD patients have been rare. METHODS: Automated enzymatic analysis was used to determine serum UA levels in 68 healthy controls and 88 PD patients, including those at the early (n = 56) and middle-late (n = 32) stages of the disease. Evaluation of motor symptoms and nonmotor symptoms in PD patients was assessed by the associated scales. Image acquisition was performed using a Siemens MAGNETOM Prisma 3 T MRI scanner. RESULTS: Serum UA levels in early stage PD patients were lower than those in healthy controls, and serum UA levels in the middle-late stage PD patients were lower than those in the early stage PD patients. Serum UA levels were significantly negatively correlated with the disease course, dysphagia, anxiety, depression, apathy, and cognitive dysfunction. ROC assessment confirmed that serum UA levels had good predictive accuracy for PD with dysphagia, anxiety, depression, apathy, and cognitive dysfunction. Furthermore, UA levels were significantly positively correlated with gray matter volume in whole brain. CONCLUSIONS: This study shows that serum UA levels were correlated with the nonmotor symptoms of dysphagia, anxiety, depression, apathy, and cognitive dysfunction and the whole-brain gray matter volume. That is the first report examining the relationships between serum UA and clinical manifestations and imaging features in PD patients.


Asunto(s)
Apatía , Enfermedad de Parkinson , Progresión de la Enfermedad , Sustancia Gris/diagnóstico por imagen , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico por imagen , Ácido Úrico
6.
Neurol Sci ; 43(8): 4753-4759, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35486332

RESUMEN

BACKGROUND: Arylsulfatase A (ARSA), a lysosomal enzyme, has been shown to inhibit the aggregation and propagation of α-synuclein (α-syn) through its molecular chaperone function. The relationship between ARSA levels and Parkinson's disease (PD) in the Chinese Han population remains controversial, and few quantitative research studies have investigated the relationship between plasma ARSA levels and PD. OBJECTIVES: The purpose of this study was to investigate the relationships between ARSA levels and cognitive function in PD patients and to evaluate the association of ARSA and α-syn levels with nonmotor symptoms. METHODS: Enzyme-linked immunosorbent assay (ELISA) was used to measure the plasma ARSA and α-syn levels in 50 healthy controls, 120 PD patients (61 PD patients with no cognitive impairment (PD-NCI) and 59 PD patients with cognitive impairment (PD-CI)). Motor symptoms and nonmotor symptoms (cognitive function, Unified Parkinson's Disease Rating Scale (UPDRS) score, depression, anxiety, constipation, olfactory dysfunction, sleep disruption, and other symptoms) were assessed with the relevant scales. The Kruskal-Wallis H test was used for comparison between groups, and Pearson/Spearman analysis was used for correlation analysis. RESULTS: The plasma ARSA concentrations were lower in the PD-CI group than in the PD-NCI group. The plasma α-syn levels in the PD-CI group were higher than those in the healthy control group, and the plasma ARSA levels were correlated with the Mini-Mental State Examination (MMSE scores) and Hoehn and Yahr (H-Y) stage. CONCLUSION: We used a quantitative assessment method to show that low plasma ARSA levels and high α-syn levels are related to cognitive impairment in PD patients. Plasma ARSA levels gradually decrease with PD progression.


Asunto(s)
Disfunción Cognitiva , Enfermedad de Parkinson , Ansiedad , Cerebrósido Sulfatasa , Cognición , Disfunción Cognitiva/complicaciones , Humanos , Enfermedad de Parkinson/diagnóstico
7.
Int J Mol Sci ; 23(24)2022 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-36555764

RESUMEN

The study of insect adaptation to the defensive metabolites of host plants and various kinds of insecticides in order to acquire resistance is a hot topic in the pest-control field, but the mechanism is still unclear. In our study, we found that a general signal pathway exists in H. armigera which can regulate multiple P450s, GSTs and UGTs genes to help insects decrease their susceptibility to xenobiotics. Knockdown of HaNrf2 and HaAhR expression could significantly increase the toxicity of xenobiotics to H. armigera, and simultaneously decrease the gene expression of P450s, GSTs and UGTs which are related to the xenobiotic metabolism and synthesis of insect hormone pathways. Then, we used EMSA and dual luciferase assay to verify that a crosstalk exists between AhR and Nrf2 to regulate multiple P450s, GSTs and UGTs genes to mediate H. armigera susceptibility to plant allelochemicals and insecticides. The detoxification genes' expression network which can be regulated by Nrf2 and AhR is still unknown, and there were also no reports about the crosstalk between AhR and Nrf2 that exist in insects and can regulate multiple detoxification genes' expression. Our results provide a new general signaling pathway to reveal the adaptive mechanism of insects to xenobiotics and provides further insight into designing effective pest-management strategies to avoid the overuse of insecticides.


Asunto(s)
Insecticidas , Mariposas Nocturnas , Animales , Insecticidas/farmacología , Larva/metabolismo , Xenobióticos/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Mariposas Nocturnas/genética , Mariposas Nocturnas/metabolismo , Insectos/metabolismo , Transducción de Señal
8.
Medicine (Baltimore) ; 103(33): e39269, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39151542

RESUMEN

BACKGROUND: To summarize the clinical experience of intracranial aneurysm clipping in the treatment of ruptured intracranial aneurysms in the second trimester of pregnancy. METHODS: A case of ruptured middle cerebral aneurysm in the second trimester of pregnancy was reported. Craniotomy and aneurysm clipping were performed at 24 weeks of pregnancy, and fetal preservation was continued after the operation. RESULTS: The prognosis of the parturient was good and the skull was missing on the operative side. A healthy baby boy was delivered by cesarean section 2 months after the operation, and skull repair was performed 4 months after the operation. During the follow-up for 1 year, the mother and son were healthy and no obvious sequelae were found. CONCLUSION: Ruptured intracranial aneurysm hemorrhage in mid-pregnancy is a rare and critical case. Summarizing the corresponding clinical experience will help to have a reference plan for the next time when facing a similar situation, and it will help to treat critically ill patients. The treatment of ruptured intracranial aneurysm in mid-pregnancy requires multidisciplinary collaboration, and cranial aneurysm clamping + fertility preservation can reduce the impact of radiation on the fetus and improve the prognosis for both the mother and the fetus.


Asunto(s)
Aneurisma Roto , Aneurisma Intracraneal , Segundo Trimestre del Embarazo , Humanos , Embarazo , Femenino , Aneurisma Intracraneal/cirugía , Aneurisma Intracraneal/complicaciones , Aneurisma Roto/cirugía , Aneurisma Roto/complicaciones , Adulto , Complicaciones Cardiovasculares del Embarazo/cirugía , Complicaciones Cardiovasculares del Embarazo/terapia , Craneotomía/métodos , Cesárea
9.
Heliyon ; 10(10): e30594, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38774318

RESUMEN

Aim: Disturbed intestinal microbiota has been implicated in the inflammatory microenvironment of the colon, which usually results in ulcerative colitis (UC). Given the limitations of these drugs, it is important to explore alternative means of protecting the gut health from UC. This study aimed to investigate the potential of polysaccharides as beneficial nutrients in the regulation of the gut microbiota, which determines the inflammatory microenvironment of the colon. Materials and methods: Mice were treated with dextran sulfate sodium (DSS) to evaluate the effects and mechanisms of Lycium barbarum polysaccharide (LBP) in remodeling the inflammatory microenvironment and improving gut health. Body weight and disease activity indices were monitored daily. Hematoxylin and eosin staining was used to analyze colon dynamics. The levels of inflammatory indicators and expression of MUC-2, claudin-1, ZO-1, and G-protein-coupled receptor 5 (TGR5) were determined using assay kits and immunohistochemistry, respectively. 16S rRNA high-throughput sequencing of the intestinal microbiota and liquid chromatography-tandem mass spectrometry for related bile acids were used. Results: LBP significantly improved the colonic tissue structure by upregulating MUC-2, claudin-1, and ZO-1 protein expression. The bacterial genus Dubosiella was dominant in healthy mice, but significantly decreased in mice treated with DSS. LBP rehabilitated Dubosiella in the sick guts of DSS mice to a level close to that of healthy mice. The levels of other beneficial bacterial genera Akkermansia and Bifidobacterium were also increased, whereas those of the harmful bacterial genera Turicibacter, Clostridium_sensu_stricto_1, Escherichia-Shigella, and Faecalibaculum decreased. The activity of beneficial bacteria promoted the bile acids lithocholic and deoxycholic acids in mice with UC, which improved the gut barrier function through the upregulation of TGR5. Conclusion: The inflammatory microenvironment in the gut is determined by the balance of the gut microbiota. LBP showed great potential as a beneficial nutrient for rehabilitating Dubosiella which is dominant in the gut of healthy mice. Nutrient-related LBP may play an important role in gut health management.

10.
J Adv Res ; 2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38286302

RESUMEN

INTRODUCTION: Unscientific application of insecticides has led to severe resistance of pests to almost all classes of insecticides. Enhanced detoxification is the most common mechanism for this kind of resistance. OBJECT: Fall armyworm (FAW) has developed insecticide resistance, which is often linked to the overexpression of detoxification genes. Herein, a multicomponent nano-pesticide is designed to increase its broad-spectrum susceptibility toward insecticides. METHOD: Regulatory function of nuclear factor erythroid 2-related factor 2 (Nrf2) in detoxification was confirmed using transcriptome sequencing, quantitative real-time PCR and enzyme activity measurement. A star polycation (SPc) was adopted to construct the pesticide/SPc/complex, whose self-assembly mechanism and characterization were examined using isothermal titration calorimetry, dynamic light scattering and transmission electron microscope. The delivery efficiency of SPc-loaded dsRNA was examined in vitro and in vivo using fluorescent tracer technique. A multicomponent nano-pesticide was created through the integration of bacterial expression system and nano-delivery system, and its bioactivity was tested in laboratory and field. RESULTS: We confirmed the crucial role of Nrf2 in regulating the detoxification in FAW, and silencing Nrf2 could decrease detoxification gene expression and increase insecticide susceptibility. We then applied the SPc to self-assemble a nanoplatform for delivering Nrf2 double-stranded RNA (dsRNA) and pesticide simultaneously. Nano-sized pesticide/SPc/dsRNA complex exhibited high delivery efficiency in vitro and in vivo. Excitingly, the insecticidal activities of pesticide/SPc/dsNrf2 complexes were remarkably improved with the normalized synergistic ratios of 5.43-6.25 for chlorantraniliprole, 4.45-15.00 for emamectin benzoate, and 6.75-15.00 for spinetoram. Finally, we developed a multicomponent nano-pesticide (pesticide/SPc/dsNrf2 complex) using a bacterial expression system and nano-delivery system. This approach exhibited excellent leaf protection and pest control efficacy. CONCLUSION: The integration between the pesticide nanometerization and insecticide susceptibility improvement offers a promising strategy to increase insecticidal activity. Our study provides a revolutionary and universal strategy to increase insecticidal activity and decease application doses.

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