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1.
Adv Sci (Weinh) ; : e2400569, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38666385

RESUMEN

The photoreceptor cilium is vital for maintaining the structure and function of the retina. However, the molecular mechanisms underlying the photoreceptor cilium integrity and retinal homeostasis are largely unknown. Herein, it is shown that kinesin family member 11 (KIF11) localizes at the transition zone (connecting cilium) of the photoreceptor and plays a crucial role in orchestrating the cilium integrity. KIF11 depletion causes malformations of both the photoreceptor ciliary axoneme and membranous discs, resulting in photoreceptor degeneration and the accumulation of drusen-like deposits throughout the retina. Mechanistic studies show that the stability of KIF11 is regulated by an interplay between its UFMylation and ubiquitination; UFMylation of KIF11 at lysine 953 inhibits its ubiquitination by synoviolin 1 and thereby prevents its proteasomal degradation. The lysine 953-to-arginine mutant of KIF11 is more stable than wild-type KIF11 and also more effective in reversing the ciliary and retinal defects induced by KIF11 depletion. These findings identify a critical role for KIF11 UFMylation in the maintenance of photoreceptor cilium integrity and retinal homeostasis.

2.
Materials (Basel) ; 17(7)2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38612215

RESUMEN

The spectral and spatial characteristics of Acousto-Optic Tunable Filters (AOTFs), such as a tuning curve, spectral resolution, angular aperture, and diffraction efficiency, are determined by the device's acousto-optic crystal configuration and piezoelectric transducer. For high-throughput spectral imaging applications, it is essential to enlarge the spectral bandwidth and angular aperture during the design phase of AOTFs. Thus, phase mismatch due to incident angle or wavelength was studied analytically using phase diagrams in this paper. Additionally, a performance parameter analysis model was established based on the use of mercurous bromide crystals for large angular aperture AOTF device design, and the impact of crystal and transducer design parameters on the spectral bandwidth and angular aperture was evaluated. This also experimentally validates the diffraction capability of AOTFs made from mercurous bromide crystal, which possess a broad spectral transmission ability ranging from visible to long-wave infrared.

3.
Materials (Basel) ; 17(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38473440

RESUMEN

The angular and spectral properties crucial for the functionality of acousto-optic (AO) devices are determined by phase-matching geometries in AO interactions. In applications such as spectral imagers based on acousto-optic tunable filters (AOTFs), systematic throughput is constrained by the angle separating diffracted and transmitted light. This research introduces an analytical model that elucidates the angular-spectral properties of diffracted beams in mercurous halide crystals. These crystals possess a wide transmissive spectral range, from visible light to long-wave infrared light. The study computes and confirms correlations between the separation angle and parameters including incident angle, polarization, acoustic angle, and crystal birefringence. Experimental validation conducted on mercurous halide and tellurium dioxide crystals demonstrates that higher birefringence in crystals significantly amplifies the separation angle, augmenting the device's performance. The study contributes to the development of devices with large separation angles during the design phase, enhancing systematic throughput in spectral imaging applications.

4.
Eur J Med Chem ; 268: 116254, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38377826

RESUMEN

Pyroptosis is one kind of programmed cell death in which the cell membrane ruptures and subsequently releases cell contents and pro-inflammatory cytokines including IL-1ß and IL-18. Pyroptosis is caused by many types of pathological stimuli, such as hyperglycemia (HG), oxidative stress, and inflammation, and is mediated by gasdermin (GSDM) protein family. Increasing evidence indicates that pyroptosis plays an important role in multiple diseases, such as cancer, kidney diseases, inflammatory diseases, and cardiovascular diseases. Therefore, the regulation of pyroptosis is crucial for the occurrence, development, and treatment of many diseases. Hydrogen sulfide (H2S) is a biologically active gasotransmitter following carbon monoxide (CO) and nitrogen oxide (NO) in mammalian tissues. So far, three enzymes, including 3-mercaptopyruvate sulphurtransferase (3-MST), cystathionine γ- Lyase (CSE), and Cystine ß-synthesis enzyme (CBS), have been found to catalyze the production of endogenous H2S in mammals. H2S has been reported to have multiple biological functions including anti-inflammation, anti-oxidative stress, anti-apoptosis and so on. Hence, H2S is involved in various physiological and pathological processes. In recent years, many studies have demonstrated that H2S plays a critical role by regulating pyroptosis in various pathological processes, such as ischemia-reperfusion injury, alcoholic liver disease, and diabetes cardiomyopathy. However, the relevant mechanism has not been completely understood. Therefore, elucidating the mechanism by which H2S regulates pyroptosis in diseases will help understand the pathogenesis of multiple diseases and provide important new avenues for the treatment of many diseases. Here, we reviewed the progress of H2S regulation of pyroptosis in different pathological processes, and analyzed the molecular mechanism in detail to provide a theoretical reference for future related research.


Asunto(s)
Sulfuro de Hidrógeno , Animales , Humanos , Sulfuro de Hidrógeno/metabolismo , Piroptosis , Inflamación , Óxido Nítrico/metabolismo , Citocinas , Mamíferos/metabolismo
5.
BMC Infect Dis ; 24(1): 214, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38369460

RESUMEN

BACKGROUND: Application of accumulated experience and management measures in the prevention and control of coronavirus disease 2019 (COVID-19) has generally depended on the subjective judgment of epidemic intensity, with the quality of prevention and control management being uneven. The present study was designed to develop a novel risk management system for COVID-19 infection in outpatients, with the ability to provide accurate and hierarchical control based on estimated risk of infection. METHODS: Infection risk was estimated using an auto regressive integrated moving average model (ARIMA). Weekly surveillance data on influenza-like-illness (ILI) among outpatients at Xuanwu Hospital Capital Medical University and Baidu search data downloaded from the Baidu Index in 2021 and 22 were used to fit the ARIMA model. The ability of this model to estimate infection risk was evaluated by determining the mean absolute percentage error (MAPE), with a Delphi process used to build consensus on hierarchical infection control measures. COVID-19 control measures were selected by reviewing published regulations, papers and guidelines. Recommendations for surface sterilization and personal protection were determined for low and high risk periods, with these recommendations implemented based on predicted results. RESULTS: The ARIMA model produced exact estimates for both the ILI and search engine data. The MAPEs of 20-week rolling forecasts for these datasets were 13.65% and 8.04%, respectively. Based on these two risk levels, the hierarchical infection prevention methods provided guidelines for personal protection and disinfection. Criteria were also established for upgrading or downgrading infection prevention strategies based on ARIMA results. CONCLUSION: These innovative methods, along with the ARIMA model, showed efficient infection protection for healthcare workers in close contact with COVID-19 infected patients, saving nearly 41% of the cost of maintaining high-level infection prevention measures and enhancing control of respiratory infections.


Asunto(s)
COVID-19 , Infección Hospitalaria , Virosis , Humanos , Infección Hospitalaria/epidemiología , Infección Hospitalaria/prevención & control , Pacientes Ambulatorios , Control de Infecciones
6.
Nat Commun ; 15(1): 365, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38191484

RESUMEN

WDR44 prevents ciliogenesis initiation by regulating RAB11-dependent vesicle trafficking. Here, we describe male patients with missense and nonsense variants within the WD40 repeats (WDR) of WDR44, an X-linked gene product, who display ciliopathy-related developmental phenotypes that we can model in zebrafish. The patient phenotypic spectrum includes developmental delay/intellectual disability, hypotonia, distinct craniofacial features and variable presence of brain, renal, cardiac and musculoskeletal abnormalities. We demonstrate that WDR44 variants associated with more severe disease impair ciliogenesis initiation and ciliary signaling. Because WDR44 negatively regulates ciliogenesis, it was surprising that pathogenic missense variants showed reduced abundance, which we link to misfolding of WDR autonomous repeats and degradation by the proteasome. We discover that disease severity correlates with increased RAB11 binding, which we propose drives ciliogenesis initiation dysregulation. Finally, we discover interdomain interactions between the WDR and NH2-terminal region that contains the RAB11 binding domain (RBD) and show patient variants disrupt this association. This study provides new insights into WDR44 WDR structure and characterizes a new syndrome that could result from impaired ciliogenesis.


Asunto(s)
Ciliopatías , Genes Ligados a X , Repeticiones WD40 , Animales , Humanos , Masculino , Encéfalo , Ciliopatías/genética , Cognición , Pez Cebra/genética
7.
J Cell Physiol ; 239(4): e31195, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38230579

RESUMEN

Phosphatidylinositol 4-kinase beta (PI4KB) is a member of the PI4K family, which is mainly enriched and functions in the Golgi apparatus. The kinase domain of PI4KB catalyzes the phosphorylation of phosphatidylinositol to form phosphatidylinositol 4-phosphate, a process that regulates various sub-cellular events, such as non-vesicular cholesterol and ceramide transport, protein glycosylation, and vesicle transport, as well as cytoplasmic division. In this study, a strain of PI4KB knockout mouse, immunofluorescence, reverse transcription polymerase chain reaction and microinjection were used to characterize the cytological location and biological function of PI4KB in the mouse embryos. we found that knocking down Pi4kb in mouse embryos resulted in embryonic lethality at around embryonic day (E) 7.5. Additionally, we observed dramatic fluctuations in PI4KB expression during the development of preimplantation embryos, with high expression in the 4-cell and morula stages. PI4KB colocalized with the Golgi marker protein TGN46 in the perinuclear and cytoplasmic regions in early blastomeres. Postimplantation, PI4KB was highly expressed in the epiblast of E7.5 embryos. Treatment of embryos with PI4KB inhibitors was found to inhibit the development of the morula into a blastocyst and the normal progression of cytoplasmic division during the formation of a 4-cell embryo. These findings suggest that PI4KB plays an important role in mouse embryogenesis by regulating various intracellular vital functions of embryonic cells.


Asunto(s)
1-Fosfatidilinositol 4-Quinasa , Embrión de Mamíferos , Ratones , Animales , Blastocisto/fisiología , Desarrollo Embrionario/genética , Ratones Noqueados
8.
Mol Neurobiol ; 61(3): 1271-1281, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37697221

RESUMEN

Autophagy is a conservative self-degradation system, which includes the two major processes of enveloping abnormal proteins, organelles and other macromolecules, and transferring them into lysosomes for the subsequent degradation. It holds the stability of the intracellular environment under stress. So far, three types of autophagy have been found: microautophagy, chaperone-mediated autophagy and macroautophagy. Many diseases have the pathological process of autophagy dysfunction, such as nervous system diseases. Pyroptosis is one kind of programmed cell death mediated by gasdermin (GSDM). In this process of pyroptosis, the activated caspase-3, caspase-4/5/11, or caspase-1 cleaves GSDM into the N-terminal pore-forming domain (PFD). The oligomer of PFD combines with the cell membrane to form membrane holes, thus leading to pyroptosis. Pyroptosis plays a key role in multiple tissues and organs. Many studies have revealed that autophagy and pyroptosis participate in the nervous system, but the mechanisms need to be fully clarified. Here, we focused on the recent articles on the role and mechanism of pyroptosis and autophagy in the pathological processes of the nervous system.


Asunto(s)
Inflamasomas , Piroptosis , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Autofagia , Sistema Nervioso/metabolismo , Caspasas/metabolismo
9.
J Cell Biol ; 223(1)2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38032388

RESUMEN

In vertebrates, multiciliated cells (MCCs) are terminally differentiated cells that line the airway tracts, brain ventricles, and reproductive ducts. Each MCC contains dozens to hundreds of motile cilia that beat in a synchronized manner to drive fluid flow across epithelia, the dysfunction of which is associated with a group of human diseases referred to as motile ciliopathies, such as primary cilia dyskinesia. Given the dynamic and complex process of multiciliogenesis, the biological events essential for forming multiple motile cilia are comparatively unelucidated. Thanks to advancements in genetic tools, omics technologies, and structural biology, significant progress has been achieved in the past decade in understanding the molecular mechanism underlying the regulation of multiple motile cilia formation. In this review, we discuss recent studies with ex vivo culture MCC and animal models, summarize current knowledge of multiciliogenesis, and particularly highlight recent advances and their implications.


Asunto(s)
Cilios , Ciliopatías , Animales , Humanos , Diferenciación Celular , Epitelio , Modelos Animales
10.
J Mol Cell Biol ; 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38059869

RESUMEN

Carbohydrate metabolism disorders (CMDs), such as diabetes, galactosemia, and mannosidosis, cause ciliopathy-like multiorgan defects. However, the mechanistic link of cilia to CMD complications is still poorly understood. Herein, we describe a significant cilium disassembly upon treatment of cells with pathologically relevant aldoses rather than the corresponding sugar alcohols. Moreover, environmental aldehydes are able to trigger cilium disassembly by the steric hindrance effect of their formyl groups. Mechanistic studies reveal that aldehydes stimulate extracellular calcium influx across the plasma membrane, which subsequently activates the calmodulin-Aurora A-histone deacetylase 6 pathway to deacetylate axonemal microtubules and triggers cilium disassembly. In vivo experiments further show that Hdac6 knockout mice are resistant to aldehyde-induced disassembly of tracheal cilia and sperm flagella. These findings reveal a previously unrecognized role for formyl group-mediated cilium disassembly in the complications of CMDs.

12.
Front Pharmacol ; 14: 1280308, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37886126

RESUMEN

With an increasing worldwide prevalence, hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver in the world. It is also the primary reason for cancer-related death in the world. The pathogenesis of HCC is complex, such as DNA methylation changes, immune regulatory disorders, cell cycle disorders, chromosomal instability, and so on. Although many studies have been conducted on HCC, the molecular mechanisms of HCC are not completely understood. At present, there is no effective treatment for HCC. Hydrogen sulfide (H2S) has long been regarded as a toxic gas with the smell of rotten eggs, but recent studies have shown that it is an important gasotransmitter along with carbon monoxide (CO) and nitric oxide (NO). Increasing evidence indicates that H2S has multiple biological functions, such as anti-inflammation, anti-apoptosis, anti-oxidative stress, and so on. Recently, a lot of evidence has shown that H2S has a "double-edged sword" effect in HCC, but the mechanism is not fully understood. Here, we reviewed the progress on the role and mechanism of H2S in HCC in recent years, hoping to provide a theoretical reference for future related research.

13.
Biosens Bioelectron ; 237: 115534, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37527624

RESUMEN

A double-cycle system has been developed for specifically detecting trace amounts of Pb2+ by significantly decreasing the background signal. The detection involves two types of RNA cleavage reactions: one using a Pb2+-specific GR5 DNAzyme (PbDz) and the other utilizing a newly constructed 10-23 DNAzyme with two hairpins embedded in its catalytic center (hpDz). The ring-structured hpDz (c-hpDz) exhibits significantly lower activity compared to the circular 10-23 DNAzyme without hairpin structures, which plays a crucial role in reducing the background signal. When Pb2+ is present, PbDz cleaves c-hpDz to its active form, which then disconnects the molecular beacon to emit the fluorescent signal. The method allows for rapid and sensitive Pb2+ detection within 40 min for 10 fM of Pb2+ and even as short as 10 min for 100 nM of Pb2+. Additionally, visual detection is possible through the non-crosslinking assembly of Au nanoparticles. The entire process can be performed in one pot and even one step, making it highly versatile and suitable for a wide range of applications, including food safety testing and environmental monitoring.


Asunto(s)
Técnicas Biosensibles , ADN Catalítico , Nanopartículas del Metal , ADN Catalítico/química , Plomo , Oro/química , Nanopartículas del Metal/química , Técnicas Biosensibles/métodos , Límite de Detección
14.
Phytother Res ; 37(10): 4740-4754, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37559472

RESUMEN

Gastric cancer (GC) is one of the most common malignant tumors worldwide. Thus, the development of safe and effective therapeutic compounds for GC treatment is urgently required. Here, we aimed to examine the role of picropodophyllin (PPP), a compound extracted from the rhizome of Dysosma versipellis (Hance) M. Cheng ex Ying, on the proliferation of GC cells. Our study revealed that PPP inhibits the proliferation of GC cells in a dose-dependent manner by inducing apoptosis. Moreover, our study elucidated that PPP suppresses the growth of GC tumor xenografts with no side effects of observable toxicity. Mechanistically, PPP exerts its effects by blocking the AKT/mammalian target of rapamycin (mTOR) signaling pathway; these effects are markedly abrogated by the overexpression of constitutively active AKT. Furthermore, drug affinity responsive target stability (DARTS) and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) revealed that heat shock protein 90 (HSP90) may be a potential target of PPP. Surface plasmon resonance and immunoprecipitation assay validated that PPP directly targets HSP90 and disrupts the binding of HSP90 to AKT, thereby suppressing GC cell proliferation. Thus, our study revealed that PPP may be a promising therapeutic compound for GC treatment.

15.
Elife ; 122023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37466224

RESUMEN

The BBSome is an octameric protein complex that regulates ciliary transport and signaling. Mutations in BBSome subunits are closely associated with ciliary defects and lead to ciliopathies, notably Bardet-Biedl syndrome. Over the past few years, there has been significant progress in elucidating the molecular organization and functions of the BBSome complex. An improved understanding of BBSome-mediated biological events and molecular mechanisms is expected to help advance the development of diagnostic and therapeutic approaches for BBSome-related diseases. Here, we review the current literature on the structural assembly, transport regulation, and molecular functions of the BBSome, emphasizing its roles in cilium-related processes. We also provide perspectives on the pathological role of the BBSome in ciliopathies as well as how these can be exploited for therapeutic benefit.


Asunto(s)
Síndrome de Bardet-Biedl , Ciliopatías , Humanos , Cilios/metabolismo , Ciliopatías/genética , Ciliopatías/metabolismo , Síndrome de Bardet-Biedl/genética , Síndrome de Bardet-Biedl/metabolismo
16.
Materials (Basel) ; 16(12)2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37374427

RESUMEN

Spectral imaging detection using acousto-optical tunable filters (AOTFs) faces a significant challenge of low throughput due to the traditional design that only receives a single polarization light. To overcome this issue, we propose a novel polarization multiplexing design and eliminate the need for crossed polarizers in the system. Our design allows for simultaneous collection of ±1 order light from the AOTF device, resulting in a more than two-fold increase in system throughput. Our analysis and experimental results validate the effectiveness of our design in improving system throughput and enhancing the imaging signal-to-noise ratio (SNR) by approximately 8 dB. In addition, AOTF devices used in polarization multiplexing applications require optimized crystal geometry parameter design that does not follow the parallel tangent principle. This paper proposes an optimization strategy for arbitrary AOTF devices which can achieve similar spectral effects. The implications of this work are significant for target detection applications.

17.
Opt Lett ; 48(13): 3395-3398, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37390139

RESUMEN

The refractive index is a key factor in the design and analysis of noncollinear acousto-optic tunable filter (AOTF) devices. While previous studies have corrected and analyzed the effects of anisotropic birefringence and the rotatory property, they still rely on paraxial and elliptical approximations, which can introduce non-negligible errors (0.5° or more) into the geometric parameters of TeO2 noncollinear AOTF devices. In this paper, we address these approximations and their effects through refractive index correction. This fundamental theoretical research has significant implications for the design and application of noncollinear AOTF devices.


Asunto(s)
Ojo , Refractometría , Birrefringencia , Rotación
18.
Front Pharmacol ; 14: 1150325, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37153780

RESUMEN

Inflammasomes play an important role in innate immunity. As a signal platform, they deal with the excessive pathogenic products and cellular products related to stress and injury. So far, the best studied and most characteristic inflammasome is the NLR-family pyrin domain-containing protein 3(NLRP3) inflammasome, which is composed of NLRP3, apoptosis associated speck like protein (ASC) and pro-caspase-1. The formation of NLRP3 inflammasome complexes results in the activation of caspase-1, the maturation of interleukin (IL)-1ß and IL-18, and pyroptosis. Many studies have demonstrated that NLRP3 inflammasome not only participates in tumorigenesis, but also plays a protective role in some cancers. Hepatocellular carcinoma (HCC) is a major cause of cancer-related mortality. Currently, due to the lack of effective treatment methods for HCC, the therapeutic effect of HCC has not been ideal. Therefore, it is particularly urgent to explore the pathogenesis of HCC and find its effective treatment methods. The increasing evidences indicate that NLRP3 inflammasome plays a vital role in HCC, however, the related mechanisms are not fully understood. Hence, we focused on the recent progress about the role of NLRP3 inflammasome in HCC, and analyzed the relevant mechanisms in detail to provide reference for the future in-depth researches.

19.
Materials (Basel) ; 16(10)2023 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-37241335

RESUMEN

Acousto-optic interaction geometry determines the spectral and spatial response of an acousto-optic tunable filter (AOTF). The precise calibration of the acousto-optic interaction geometry of the device is a necessary process before designing and optimizing optical systems. In this paper, we develop a novel calibration method based on the polar angular performance of an AOTF. A commercial AOTF device with unknown geometry parameters was experimentally calibrated. The experimental results show high precision, in some cases falling within 0.01°. In addition, we analyzed the parameter sensitivity and Monte Carlo tolerance of the calibration method. The results of the parameter sensitivity analysis show that the principal refractive index has a large influence on the calibration results, while other factors have little influence. The results of the Monte Carlo tolerance analysis show that the probability of the results falling 0.1° using this method is greater than 99.7%. This work provides an accurate and easy-to-perform method for AOTF crystal calibration and can contribute to the characteristic analysis of AOTFs and the optical design of spectral imaging systems.

20.
Front Pharmacol ; 14: 1172147, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37124222

RESUMEN

Endoplasmic reticulum (ER) is an important organelle for protein translation, folding and translocation, as well as the post-translational modification and assembly of newly synthesized secreted proteins. When the excessive accumulation of misfolded and/or unfolded proteins exceeds the processing capacity of ER, ER stress is triggered. The integrated intracellular signal cascade, namely the unfolded protein response, is induced to avoid ER stress. ER stress is involved in many pathological and physiological processes including myocardial diseases. For a long time, hydrogen sulfide (H2S) has been considered as a toxic gas with the smell of rotten eggs. However, more and more evidences indicate that H2S is an important gas signal molecule after nitric oxide and carbon monoxide, and regulates a variety of physiological and pathological processes in mammals. In recent years, increasing studies have focused on the regulatory effects of H2S on ER stress in myocardial diseases, however, the mechanism is not very clear. Therefore, this review focuses on the role of H2S regulation of ER stress in myocardial diseases, and deeply analyzes the relevant mechanisms so as to lay the foundation for the future researches.

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