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1.
Arch Biochem Biophys ; 759: 110102, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39029644

RESUMEN

Abdominal aortic aneurysm (AAA) is a dangerous condition affecting the aorta. Macrophage pyroptosis, phenotypic transformation, and apoptosis of aortic smooth muscle cells (ASMCs) are pivotal mechanisms in AAA pathogenesis. This study explores how Gasdermin B (GSDMB) regulates macrophage non-canonical pyroptosis and its impact on the phenotypic transformation and apoptosis of ASMCs, thereby unveiling the role of GSDMB in AAA pathogenesis. Immunofluorescence analysis was used to assess the expression levels and localization of GSDMB, cysteinyl aspartate-specific protease-4 (Caspase-4), and N-terminal of cleaved GSDMD (N-GSDMD) in AAA tissues. A cell model that mimics macrophage non-canonical pyroptosis was established by treating THP-1 cells with lipopolysaccharide (LPS). THP-1 cells with reduced or increased GSDMB were generated using small interfering RNA (siRNA) or plasmids. Co-culture experiments involving THP-1 cells and HASMCs were conducted to explore the impact of GSDMB on HASMCs. The mitochondrial reactive oxygen species (mtROS) scavenger Mito-TEMPO lowered mtROS levels in THP-1 cells. Our findings revealed that GSDMB was significantly upregulated in AAA macrophages, which was accompanied by robust non-canonical pyroptosis. THP-1 cells showed non-canonical pyroptosis in response to LPS, which was accompanied by an increase in GSDMB. Further research demonstrated that altering GSDMB, either by knockdown or overexpression, can affect macrophage non-canonical pyroptosis as well as the phenotypic transformation and apoptosis of HASMCs. LPS-induced non-canonical pyroptosis in THP-1 cells was associated with an increase in mtROS, whereas Mito-TEMPO effectively decreased non-canonical pyroptosis and the expression of GSDMB. These findings suggest that GSDMB plays a role in AAA macrophage non-canonical pyroptosis, which influences the phenotypic transformation and apoptosis of HASMCs. The mtROS-Dynamin-Related Protein 1 (Drp1) axis is likely to regulate the GSDMB-mediated non-canonical pyroptosis.

2.
Pediatr Infect Dis J ; 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38985999

RESUMEN

Pentavalent rotavirus vaccine (RV5) coverage and changes in rotavirus detection in the prevaccine and postvaccine era in Chengdu were investigated. The results showed that the coverage of RV5 had been increasing but still relatively low. Nevertheless, the dramatical decline in the rotavirus detection was observed after the introduction of RV5. Efforts to improve the coverage of rotavirus vaccination should continue to maximize the public health benefits.

3.
BMJ Open ; 14(7): e084900, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025823

RESUMEN

INTRODUCTION: Care workers play a fundamental role in delivering care services in long-term care institutions. Burnout has been found to have a negative impact on care recipients and organisations providing care. Little is known about the key factors associated with care workers' burnout. This systematic review aims to explore the prevalence, severity and correlates of burnout among care workers before and during COVID-19 pandemic. METHODS AND ANALYSIS: A five-stage framework outlined by Whittemore and Knafl will be used. The following databases will be used to identify relevant literature, including Medline (PubMed), EMBASE, Cochrane library, PsycINFO, CINAHL, Scopus and Web of Science. RevMan will be used to assist the meta-analysis. Heterogeneity of the included studies will be tested using the I 2 test. ETHICS AND DISSEMINATION: No ethics approval is required as this study only involves secondary data analysis. The findings will be published in peer-reviewed journals and presented at relevant conferences. PROSPERO REGISTRATION NUMBER: CRD42024499178.


Asunto(s)
Agotamiento Profesional , COVID-19 , Cuidados a Largo Plazo , Metaanálisis como Asunto , Revisiones Sistemáticas como Asunto , Humanos , Agotamiento Profesional/epidemiología , COVID-19/epidemiología , COVID-19/psicología , Personal de Salud/psicología , SARS-CoV-2 , Proyectos de Investigación
4.
Mol Med ; 30(1): 90, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886644

RESUMEN

BACKGROUND: Aortic dissection (AD) is a macrovascular disease which is pathologically characterized by aortic media degeneration.This experiment aims to explore how iron deficiency (ID) affects the function of vascular smooth muscle cell (VSMC) and participates in the occurrence and development of AD by regulating gene expression. METHODS: The relationship between iron and AD was proved by Western-blot (WB) and immunostaining experiments in human and animals. Transcriptomic sequencing explored the transcription factors that were altered downstream. WB, flow cytometry and immunofluorescence were used to demonstrate whether ID affected HIF1 expression through oxygen transport. HIF1 signaling pathway and phenotypic transformation indexes were detected in cell experiments. The use of the specific HIF1 inhibitor PX478 further demonstrated that ID worked by regulating HIF1. RESULTS: The survival period of ID mice was significantly shortened and the pathological staining results were the worst. Transcriptomic sequencing indicated that HIF1 was closely related to ID and the experimental results indicated that ID might regulate HIF1 expression by affecting oxygen balance. HIF1 activation regulates the phenotypic transformation of VSMC and participates in the occurrence and development of AD in vivo and in vitro.PX478, the inhibition of HIF1, can improve ID-induced AD exacerbation.


Asunto(s)
Disección Aórtica , Músculo Liso Vascular , Miocitos del Músculo Liso , Oxígeno , Transducción de Señal , Animales , Humanos , Masculino , Ratones , Disección Aórtica/metabolismo , Disección Aórtica/etiología , Disección Aórtica/genética , Disección Aórtica/patología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Factor 1 Inducible por Hipoxia/metabolismo , Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Deficiencias de Hierro , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/metabolismo , Oxígeno/metabolismo , Fenotipo
5.
Front Immunol ; 15: 1368727, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38895126

RESUMEN

Background: Psoriasis is a chronic dermatological condition characterized by a complex pathogenesis that impacts approximately 3% of adults in the United States and brings enormous social burdens. For many diseases, the systemic immune-inflammatory index (SII), defined as neutrophils × platelets/lymphocytes, has been recognized as a prognostic indicator. Therefore, we conducted a cross-sectional study to assess the association between SII and psoriasis among outpatient US adults. Methods: In this cross-sectional study, we used data on the US adults 20 to 59 years of age from the National Health and Nutrition Examination Survey (NHANES) spanning 2003-2006 and 2009-2014. Sample-weighted logistic regression and stratified analysis of subgroups were used. Results: Among the 16,831 adults, there were 8,801 women and 8,030 men, with a psoriasis prevalence rate of 3.0%. A fully adjusted model revealed a positive association between a SII higher than 479.15 × 109/L and a high risk of psoriasis. According to subgroup analysis and interaction testing (p for interaction > 0.05), age, sex, alcohol drinking status, marital status, and body mass index (BMI) were not significantly correlated with this positive association. Conclusion: Our findings suggested that SII higher than 479.15 × 109/L was positively associated with a high risk of psoriasis among outpatient US adults. To the best of our knowledge, this is the first cross-sectional study using NHANES data focused on the risk of higher SII on psoriasis among outpatient US adults. The outcomes of this cross-sectional serve to supplement previous research, indicating a need for larger-scale prospective cohorts for further validation.


Asunto(s)
Encuestas Nutricionales , Psoriasis , Humanos , Psoriasis/inmunología , Psoriasis/epidemiología , Femenino , Masculino , Adulto , Persona de Mediana Edad , Estudios Transversales , Estados Unidos/epidemiología , Adulto Joven , Inflamación/inmunología , Pacientes Ambulatorios , Prevalencia , Neutrófilos/inmunología
6.
J Hazard Mater ; 475: 134854, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38889468

RESUMEN

Microplastics (MPs) have attracted widespread attention because they can lead to combined toxicity by adsorbing heavy metals from the environment. Exposure to lead (Pb), a frequently adsorbed heavy metal by MPs, is common. In the current study, the coexistence of MPs and Pb was assessed in human samples. Then, mice were used as models to examine how co-exposure to MPs and Pb promotes aortic medial degeneration. The results showed that MPs and Pb co-exposure were detected in patients with aortic disease. In mice, MPs and Pb co-exposure promoted the damage of elastic fibers, loss of vascular smooth muscle cells (VSMCs), and release of inflammatory factors. In vitro cell models revealed that co-exposure to MPs and Pb induced excessive reactive oxygen species generation, impaired mitochondrial function, and triggered PANoptosome assembly in VSMCs. These events led to PANoptosis and inflammation through the cAMP/PKA-ROS signaling pathway. However, the use of the PKA activator 8-Br-cAMP or mitochondrial ROS scavenger Mito-TEMPO improved, mitochondrial function in VSMCs, reduced cell death, and inhibited inflammatory factor release. Taken together, the present study provided novel insights into the combined toxicity of MPs and Pb co-exposure on the aorta.


Asunto(s)
Plomo , Microplásticos , Especies Reactivas de Oxígeno , Animales , Especies Reactivas de Oxígeno/metabolismo , Plomo/toxicidad , Humanos , Microplásticos/toxicidad , Masculino , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/patología , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Aorta/efectos de los fármacos , Aorta/patología , Músculo Liso Vascular/efectos de los fármacos , Músculo Liso Vascular/patología , Músculo Liso Vascular/metabolismo , Ratones Endogámicos C57BL , Ratones , Femenino , Persona de Mediana Edad , Enfermedades de la Aorta/inducido químicamente , Enfermedades de la Aorta/patología , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo
7.
J Leukoc Biol ; 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748684

RESUMEN

Neutrophils are essential cells involved in inflammation. However, the specific mechanism of neutrophil chemotaxis induced by Treponema Pallidum (T. pallidum) remains unknow. In this study, human umbilical vein endothelial cells (HUVECs) were utilized as target cells to investigate the expression levels of chemokines when stimulated with different concentrations of Tp0768(also known as TpN44.5 or TmpA, a T. pallidum infection dependent antigen). The results indicated that Tp0768 treatment enhanced neutrophil chemotaxis in HUVECs, which was closely associated with the expression levels of CXCL1(C-X-C Motif Chemokine Ligand 1), CXCL2(C-X-C Motif Chemokine Ligand 2), and CXCL8(C-X-C Motif Chemokine Ligand 8, also known as interleukin-8). At the same time, the results show that Toll Like Receptor 2 (TLR2) signaling pathway is activated and endoplasmic reticulum stress (ER stress) occurs. Furthermore, the findings revealed that the use of protein kinase RNA-like endoplasmic reticulum kinase (PERK) and Immunoglobulin-Regulated Enhancer 1 (IRE1) inhibitors reduced the expression levels of CXCL1, CXCL2, and CXCL8. Additionally, inhibiting TLR2 significantly decreased the expression levels of ER stress-related proteins (PERK and IRE1), CXCL1, CXCL2, and CXCL8. Consequently, neutrophil chemotaxis was significantly inhibited after treatment with TLR2, PERK, and IRE1 inhibitors. These findings shed light on the role of Tp0768 in enhancing neutrophil chemotaxis in endothelial cells, providing a foundation for further exploration of syphilis pathogenesis and offering a new direction for the diagnosis and treatment of T. pallidum infection.

8.
Biochem Pharmacol ; 219: 115967, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38065291

RESUMEN

It is well known that aortic dissection (AD) is a very aggressive class of vascular diseases. S-adenosylmethionine (SAM) is an autophagy inhibitor with anti-inflammatory and anti-oxidative stress effects; however, the role of SAM in AD is unknown. In this study, we constructed an animal model of AD using subcutaneous minipump continuous infusion of AngII-induced ApoE-/-mice and a cytopathic model using AngII-induced primary vascular smooth muscle cells (VSMCs) to investigate the possible role of SAM in AD. The results showed that mice in the AngII + SAM group had significantly lower AD incidence, significantly prolonged survival, and reduced vascular elastic fiber disruption compared with mice in the AngII group. In addition, SAM significantly inhibited autophagy in vivo and in vitro. Meanwhile, SAM also inhibited the cellular phenotypic switch, mainly by up regulating the expression levels of contractile marker proteins [α-smooth muscle actin (α-SMA) and smooth muscle 22α (SM22α)] and down regulating the expression levels of synthetic marker proteins [osteoblast protein (OPN), matrix metalloproteinase-2 (MMP2), and matrix metalloproteinase-9 (MMP9)]. Molecularly, SAM inhibited AD formation mainly by activating the PI3K/AKT/mTOR signaling pathway. Using a PI3K inhibitor (LY294002) significantly reversed the protective effect of SAM in AngII-induced mice and VSMCs.Our study demonstrates the protective effect of SAM on mice under AngII-induced AD for the first time. SAM prevented AD formation mainly by inhibiting cellular phenotypic switch and autophagy, and activation of the PI3K/AKT/mTOR signaling pathway is a possible molecular mechanism. Thus, SAM may be a novel strategy for the treatment of AD.


Asunto(s)
Angiotensina II , Disección Aórtica , Ratones , Animales , Angiotensina II/metabolismo , Músculo Liso Vascular/metabolismo , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 2 de la Matriz/metabolismo , S-Adenosilmetionina/metabolismo , S-Adenosilmetionina/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Disección Aórtica/inducido químicamente , Disección Aórtica/prevención & control , Serina-Treonina Quinasas TOR/metabolismo , Miocitos del Músculo Liso , Células Cultivadas , Autofagia
10.
J Transl Med ; 21(1): 925, 2023 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-38124174

RESUMEN

BACKGROUND: Heart transplantation (HT) has been approved as an optimal therapeutic regimen for patients with terminal-stage cardiac failure. However, cold ischaemia‒reperfusion (I/R) injury remains an unavoidable and outstanding challenge, which is a major factor in early graft dysfunction and an obstacle to long-term survival in HT. Cold I/R injury induces cardiac graft injury by promoting mitochondrial dysfunction and augmenting free radical production and inflammatory responses. We therefore designed a mitochondrion-targeted nanocarrier loaded with Coenzyme Q10 (CoQ10) (CoQ10@TNPs) for treatment of cold I/R injury after cardiac graft in a murine heterotopic cardiac transplantation model. METHODS: Hybrid nanoparticles composed of CaCO3/CaP/biotinylated-carboxymethylchitosan (CaCO3/CaP/BCMC) were synthesized using the coprecipitation method, and the mitochondria-targeting tetrapeptide SS31 was incorporated onto the surface of the hybrid nanoparticles through biotin-avidin interactions. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) analysis were used for characterisation. In vitro, the hypoxia-reoxygenation model of H9c2 cells was employed to replicate in vivo cold I/R injury and treated with CoQ10@TNPs. The impact of CoQ10@TNPs on H9c2 cell injury was assessed by analysis of oxidative damage and apoptosis. In vivo, donor hearts (DHs) were perfused with preservation solution containing CoQ10@TNPs and stored in vitro at 4 °C for 12 h. The DHs were heterotopically transplanted and analysed for graft function, oxidative damage, apoptosis, and inflammatory markers 1 day post-transplantation. RESULTS: CoQ10@TNPs were successfully synthesized and delivered CoQ10 to the mitochondria of the cold ischaemic myocardium. In vitro experiments demonstrated that CoQ10@TNPs was taken up by H9c2 cells at 4 °C and localized within the mitochondria, thus ameliorating oxidative stress damage and mitochondrial injury in cold I/R injury. In vivo experiments showed that CoQ10@TNPs accumulated in DH tissue at 4 °C, localized within the mitochondria during cold storage and improved cardiac graft function by attenuating mitochondrial oxidative injury and inflammation. CONCLUSIONS: CoQ10@TNPs can precisely deliver CoQ10 to the mitochondria of cold I/R-injured cardiomyocytes to effectively eliminate mitochondrial reactive oxygen species (mtROS), thus reducing oxidative injury and inflammatory reactions in cold I/R-injured graft tissues and finally improving heart graft function. Thus, CoQ10@TNPs offer an effective approach for safeguarding cardiac grafts against extended periods of cold ischaemia, emphasizing the therapeutic potential in mitigating cold I/R injury during HT. These findings present an opportunity to enhance existing results following HT and broaden the range of viable grafts for transplantation.


Asunto(s)
Quitosano , Lesiones Cardíacas , Trasplante de Corazón , Daño por Reperfusión , Ratones , Humanos , Animales , Trasplante de Corazón/métodos , Quitosano/farmacología , Quitosano/metabolismo , Donantes de Tejidos , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/prevención & control , Daño por Reperfusión/metabolismo , Mitocondrias , Miocitos Cardíacos/metabolismo
11.
J Orthop Translat ; 43: 21-35, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37965195

RESUMEN

Background: Large defects of long tubular bones due to severe trauma, bone tumor resection, or osteomyelitis debridement are challenging in orthopedics. Bone non-union and other complications often lead to serious consequences. At present, autologous bone graft is still the gold standard for the treatment of large bone defects. However, autologous bone graft sources are limited. Silicon rubber (SR) materials are widely used in biomedical fields, due to their safety and biocompatibility, and even shown to induce nerve regeneration. Materials and methods: We extracted rat bone marrow mesenchymal stem cells (BMMSCs) in vitro and verified the biocompatibility of silicone rubber through cell experiments. Then we designed a rabbit radius critical sized bone defect model to verify the effect of silicone rubber sealed channel inducing bone repair in vivo. Results: SR sealed channel could prevent the fibrous tissue from entering the fracture end and forming bone nonunion, thereby inducing self-healing of long tubular bone through endochondral osteogenesis. The hematoma tissue formed in the early stage was rich in osteogenesis and angiogenesis related proteins, and gradually turned into vascularization and endochondral osteogenesis, and finally realized bone regeneration. Conclusions: In summary, our study proved that SR sealed channel could prevent the fibrous tissue from entering the fracture end and induce self-healing of long tubular bone through endochondral osteogenesis. In this process, the sealed environment provided by the SR channel was key, and this might indicate that the limit of self-healing of bone exceeded the previously thought. The translational potential of this article: This study investigated a new concept to induce the self-healing of large bone defects. It could avoid trauma caused by autologous bone extraction and possible rejection reactions caused by bone graft materials. Further research based on this study, including the innovation of induction materials, might invent a new type of bone inducing production, which could bring convenience to patients. We believed that this study had significant meaning for the treatment of large bone defects in clinical practice.

12.
BMC Med Educ ; 23(1): 882, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978370

RESUMEN

"Clinical basic inspection technology" is one of the essential courses in the medical laboratory profession. Combining the characteristics of the discipline itself, the research and practice of the BOPPPS model based on the OBE concept in clinical basic laboratory experiment teaching are discussed, and the reform of in teaching objectives, teaching contents, and teaching design path is implemented. The "student-centered" teaching process is divided into six stages: before, during, and after class, and the teaching process is continuously improved to achieve the desired teaching effect. Results of the experiment teaching show that the model has improved students' active participation and developed their clinical thinking skills, and more than 95% of students are satisfied with this teaching model.


Asunto(s)
Medicina , Estudiantes , Humanos , Pensamiento , Competencia Clínica , Laboratorios
13.
J Voice ; 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37891129

RESUMEN

The incidence rate of voice diseases is increasing year by year. The use of software for remote diagnosis is a technical development trend and has important practical value. Among voice diseases, common diseases that cause hoarseness include spasmodic dysphonia, vocal cord paralysis, vocal nodule, and vocal cord polyp. This paper presents a voice disease detection method that can be applied in a wide range of clinical. We cooperated with Xiangya Hospital of Central South University to collect voice samples from 352 different patients. The Mel Frequency Cepstrum Coefficient (MFCC) parameters are extracted as input features to describe the voice in the form of data. An innovative model combining MFCC parameters and single convolution layer CNN is proposed for fast calculation and classification. The highest accuracy we achieved was 92%, it is fully ahead of the original research results and internationally advanced. And we use advanced voice function assessment databases (AVFAD) to evaluate the generalization ability of the method we proposed, which achieved an accuracy rate of 98%. Experiments on clinical and standard datasets show that for the pathological detection of voice diseases, our method has greatly improved in accuracy and computational efficiency.

14.
Front Endocrinol (Lausanne) ; 14: 1212570, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37842293

RESUMEN

Aims: Evidence on the association between the risk of new-onset osteoporosis and oral anticoagulants remains controversial. We aimed to compare the risk of osteoporosis associated with the use of direct oral anticoagulants (DOACs) with that associated with warfarin use. Methods: Studies published up to 15 March 2023 that investigated the association between the use of DOACs and warfarin and the incidence of osteoporosis were identified by online searches in PubMed, Embase, the Cochrane Library, and Web of Science conducted by two independent investigators. Random-effects or fixed-effect models were employed to synthesize hazard ratios (HRs)/relative ratios (RRs) with 95% confidence intervals (CIs) for estimating the risk of osteoporosis correlated with DOAC and warfarin prescriptions (PROSPERO No. CRD42023401199). Results: Our meta-analysis ultimately included four studies involving 74,338 patients. The results suggested that DOAC use was associated with a significantly lower incidence of new-onset osteoporosis than warfarin use (pooled HR: 0.71, 95% CI: 0.57 to 0.88, p < 0.001, I 2: 85.1%). Subanalyses revealed that rivaroxaban was associated with a lower risk of osteoporosis than both warfarin and dabigatran. In addition, DOACs were associated with a lower risk of developing osteoporosis than warfarin in both male and female patients, in patients with atrial fibrillation (AF), and in patients who underwent therapy for > 365 days. Conclusion: DOAC users experienced a lower incidence of osteoporosis than warfarin users. This study may give us insight into safe anticoagulation strategies for patients who are at high risk of developing osteoporosis. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO, identifier CRD42023401199.


Asunto(s)
Fibrilación Atrial , Osteoporosis , Accidente Cerebrovascular , Humanos , Masculino , Femenino , Warfarina/efectos adversos , Accidente Cerebrovascular/epidemiología , Hemorragia/complicaciones , Anticoagulantes/efectos adversos , Fibrilación Atrial/inducido químicamente , Fibrilación Atrial/epidemiología , Fibrilación Atrial/complicaciones , Osteoporosis/inducido químicamente , Osteoporosis/tratamiento farmacológico , Osteoporosis/epidemiología
15.
Appl Opt ; 62(27): 7233-7239, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37855579

RESUMEN

Phase sensitive amplifiers (PSAs) based on optical parametric amplification feature near noiseless amplification, which is of considerable benefit for improving the performance of optical communication systems. Currently, the majority of research on PSAs is carried out on the basis of highly nonlinear fibers or periodically poled lithium niobite waveguides, with the impediments of being susceptible to environmental interference and requiring complex temperature control systems to maintain quasi-phase matching conditions, respectively. Here, a near-noiseless and small-footprint PSA based on dispersion-engineered AlGaAs-on-insulator (AlGaAsOI) waveguides is proposed and demonstrated theoretically. The phase-dependent gain and the phase-to-phase transfer function of the PSA are calculated to analyze its characteristics. Furthermore, we investigate in detail the effects of linear loss, nonlinear coefficient, and pump power on the PSA gain and noise figure (NF) in AlGaAsOI waveguides. The results show that a PSA based on an AlGaAsOI waveguide is feasible with a maximum phase sensitive gain of 33 dB, achieving an NF of less than 1 dB over a gain bandwidth of 245 nm with a gain of >15d B, which completely covers the S + C + L band. This investigation is worthwhile for noiseless PSAs on photonic integrated chips, which are promising for low-noise optical amplification, multifunctional photonic integrated chips, quantum communication, and spectroscopy, and as a reference for low-noise PSAs depending on the third-order nonlinearity, χ (3), of the waveguide material.

16.
Int Immunopharmacol ; 124(Pt A): 110922, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37699303

RESUMEN

Acute rejection may manifest following heart transplantation, despite the implementation of relatively well-established immunosuppression protocols. The significance of the mTOR signaling pathway in rejection is widely acknowledged. BEZ235, a second-generation mTOR inhibitor with dual inhibitory effects on PI3K and mTOR, holds promise for clinical applications. This study developed a nanodelivery system, BEZ235@NP, to facilitate the intracellular delivery of BEZ235, which enhances efficacy and reduces adverse effects by improving the poor solubility of BEZ235. In the complete MHCII-mismatched model, BEZ235@NP significantly prolonged cardiac allografts survival compared to free BEZ235, which was attributed to more effective suppression of effector T cell activation and promotion of greater expansion of Tregs. These nanoparticles demonstrated excellent biosafety and exhibited no short-term biotoxicity upon investigation. To elucidate the mechanism, primary T cells were isolated from the spleen and it was observed that BEZ235@NP treatment resulted in the arrest of these cells in the G0/G1 phase. As indicated by Western blot analysis, BEZ235@NP substantially reduced mTOR phosphorylation. This, in turn, suppressed downstream pathways and ultimately exerted an anti-proliferative and anti-activating effect on cells. Furthermore, it was observed that inhibition of the mTOR pathway stimulated T-cell autophagy. In conclusion, the strategy of intracellular delivery of BEZ235 presents promising applications for the treatment of acute rejection.


Asunto(s)
Quitosano , Trasplante de Corazón , Nanopartículas , Quinolinas , Animales , Ratones , Quitosano/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proliferación Celular , Quinolinas/uso terapéutico , Quinolinas/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Nanopartículas/uso terapéutico , Línea Celular Tumoral
17.
Appl Opt ; 62(23): G18-G25, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37707059

RESUMEN

Satellite free-space optical (FSO) communication is very promising in improving the bandwidth and capacity of space information networks in the future. However, the inter-satellite transmission distance of over 1000 km leads to unstable optical beam pointing, acquisition, and tracking and then generates optical power jitter by a large margin before detection-demodulation. Therefore, it is difficult to realize high-stability and long-time FSO communication between satellites due to the generated bit error rate (BER) by jitter. In this paper, we report an autonomously self-designed and high-integration laser communication payload (LCP) and on-orbit-demonstrated inter-satellite 145 min, zero-BER FSO stable communication with a line rate of 2.8 Gbps. Moreover, based on the inter-satellite laser communication link, a video phone was clearly implemented for more than 10 min, and authentic user data transmitted 459,149 packets, achieving results of zero-packet loss. Summarily, this on-orbit experiment demonstrated an excellent performance of the LCP owing to the distinctive design of integrating a high-power amplifier and low-noise amplifier optical amplification function. Our space mission was successfully completed, and the on-orbit demonstration results may offer a significant reference for the field of satellite laser communication and space information networks.

18.
Orthop Surg ; 15(4): 1045-1052, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36846936

RESUMEN

OBJECTIVE: Recently, some clinical studies have reported the use of an intramedullary nailing system for treating unstable femoral neck fractures or femoral neck fractures combined with femoral shaft fractures in young adults, and the results have indicated certain advantages. However, no study has investigated the mechanical properties of this method. We aimed to evaluate the mechanical stability and clinical efficacy of the Gamma nail combined with one cannulated compression screw (CCS) fixation for treating Pauwels type III femoral neck fracture in young and middle-aged adults. METHODS: This study consists of two parts: a clinical retrospective study and randomized controlled biomechanical test. Twelve adult cadaver femora were used to test and compare the biomechanical properties among three fixation methods: three parallel CCS (group A), Gamma nail (group B), and Gamma nail combined with one cannulated compression screw (group C). The single continuous compression test, cyclic load test, and ultimate vertical load test were used to evaluate the biomechanical performance of the three fixation methods. We also conducted a retrospective study of 31 patients with Pauwels type III femoral neck fractures, including 16 patients with fractures fixed with three parallel CCS (CCS group) and 15 patients with fractures fixed with Gamma nail combined with one CCS (Gamma nail + CCS group). The patients were followed up for at least 3 years, and all were evaluated for surgical time (from skin incision to closure), surgical blood loss, hospital stay, and the Harris hip score. RESULTS: In mechanical experiments, we have found that the mechanical advantages of Gamma nail fixation are not as good as those of conventional CCS fixation. However, the mechanical properties of Gamma nail fixation combined with one cannulated screw perpendicular to the fracture line are much better than those of Gamma nail fixation and CCS fixation. No significant difference was found in the incidence of femoral head necrosis and nonunion between the CCS and Gamma nail + CCS groups. Moreover, there was no statistically significant difference in the Harris hip scores between the two groups. One patient in the CCS group showed significant withdrawal of cannulated screws at 5 months after surgery, whereas in the Gamma nail + CCS group, all patients, including those with femoral neck necrosis, showed no loss of stability of the fixation. CONCLUSION: Among the two fixation methods evaluated in this study, Gamma nail combined with one CCS fixation showed better biomechanical properties and may reduce complications associated with unstable fixation devices.


Asunto(s)
Fracturas del Cuello Femoral , Fijación Interna de Fracturas , Persona de Mediana Edad , Adulto Joven , Humanos , Fijación Interna de Fracturas/métodos , Estudios de Seguimiento , Estudios Retrospectivos , Tornillos Óseos , Fracturas del Cuello Femoral/cirugía , Resultado del Tratamiento
19.
Mol Microbiol ; 119(1): 86-100, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36480422

RESUMEN

Endothelial cell injury is a key factor in the spread of infection and pathogenicity of Treponema pallidum. The migration and adhesion reaction mediated by T. pallidum lipoprotein plays an important role. This study aimed to systematically explore the migration and adhesion effect of T. pallidum lipoprotein Tp0768 and its molecular mechanism. Stimulating vascular endothelial cells with Tp0768 increased the expression of ICAM-1, MCP-1, and IL-8. Moreover, it promoted the migration and adhesion of THP-1 cells to vascular endothelial cells. Our results revealed that Tp0768 promoted the THP-1 cells migrating and adhering to vascular endothelial cells by the PERK and IRE-1α pathways of endoplasmic reticulum (ER) stress. We further demonstrated that the inhibition of the NF-κB pathway and the downregulation of hypoxia-inducible factor 1 alpha (HIF-1α) reduced the mRNA levels of ICAM-1, MCP-1, and IL-8 induced by Tp0768. Also, the adhesion rate of THP-1 cells to endothelial cells decreased. After inhibiting ER stress, NF-κB p65 nuclear translocation was weakened, and the mRNA level of HIF-1α was also significantly downregulated. Our results indicated that T. pallidum lipoprotein Tp0768 promoted the migration and adhesion of THP-1 cells to vascular endothelial cells through ER stress and NF-κB/HIF-1α pathway.


Asunto(s)
FN-kappa B , Treponema pallidum , Humanos , FN-kappa B/metabolismo , Treponema pallidum/genética , Treponema pallidum/metabolismo , Células THP-1 , Molécula 1 de Adhesión Intercelular/genética , Células Endoteliales/metabolismo , Interleucina-8 , ARN Mensajero/metabolismo , Retículo Endoplásmico/metabolismo
20.
Infection ; 51(2): 305-321, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36260281

RESUMEN

BACKGROUND: Syphilis is a chronic sexually transmitted disease caused by Treponema pallidum subspecies pallidum (T. pallidum), which is a public health problem that seriously affects human health worldwide. T. pallidum is characterized by early transmission and immune escape and is therefore termed an "invisible pathogen". METHODS: This review systematically summarizes the host's innate and adaptive immune responses to T. pallidum infection as well as the escape mechanisms of T. pallidum. PURPOSE: To lay the foundation for assessing the pathogenic mechanism and the systematic prevention and treatment of syphilis. CONCLUSION: The immune escape mechanism of T. pallidum plays an important role in its survival. Exploring the occurrence and development of these mechanisms has laid the foundation for the development of syphilis vaccine.


Asunto(s)
Sífilis , Treponema pallidum , Humanos , Vacunas Bacterianas
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