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1.
Annu Rev Biochem ; 85: 405-29, 2016 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-27088879

RESUMO

Sirtuins are NAD(+)-dependent enzymes universally present in all organisms, where they play central roles in regulating numerous biological processes. Although early studies showed that sirtuins deacetylated lysines in a reaction that consumes NAD(+), more recent studies have revealed that these enzymes can remove a variety of acyl-lysine modifications. The specificities for varied acyl modifications may thus underlie the distinct roles of the different sirtuins within a given organism. This review summarizes the structure, chemistry, and substrate specificity of sirtuins with a focus on how different sirtuins recognize distinct substrates and thus carry out specific functions.


Assuntos
Histonas/química , NAD/química , Processamento de Proteína Pós-Traducional , Sirtuínas/química , Acilação , Expressão Gênica , Histonas/genética , Histonas/metabolismo , Humanos , Hidrólise , Cinética , Lipoilação , Modelos Moleculares , Ácido Mirístico/química , Ácido Mirístico/metabolismo , NAD/metabolismo , Plasmodium falciparum/química , Plasmodium falciparum/enzimologia , Estrutura Secundária de Proteína , Sirtuínas/genética , Sirtuínas/metabolismo , Especificidade por Substrato , Ácido Succínico/química , Ácido Succínico/metabolismo , Thermotoga maritima/química , Thermotoga maritima/enzimologia
2.
Chem Rev ; 124(5): 2699-2804, 2024 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-38422393

RESUMO

The ability to gain spatiotemporal information, and in some cases achieve spatiotemporal control, in the context of drug delivery makes theranostic fluorescent probes an attractive and intensely investigated research topic. This interest is reflected in the steep rise in publications on the topic that have appeared over the past decade. Theranostic fluorescent probes, in their various incarnations, generally comprise a fluorophore linked to a masked drug, in which the drug is released as the result of certain stimuli, with both intrinsic and extrinsic stimuli being reported. This release is then signaled by the emergence of a fluorescent signal. Importantly, the use of appropriate fluorophores has enabled not only this emerging fluorescence as a spatiotemporal marker for drug delivery but also has provided modalities useful in photodynamic, photothermal, and sonodynamic therapeutic applications. In this review we highlight recent work on theranostic fluorescent probes with a particular focus on probes that are activated in tumor microenvironments. We also summarize efforts to develop probes for other applications, such as neurodegenerative diseases and antibacterials. This review celebrates the diversity of designs reported to date, from discrete small-molecule systems to nanomaterials. Our aim is to provide insights into the potential clinical impact of this still-emerging research direction.


Assuntos
Corantes Fluorescentes , Medicina de Precisão , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Fluorescência , Nanomedicina Teranóstica
3.
Nano Lett ; 24(14): 4082-4090, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38526914

RESUMO

The generally nonpolar SrTiO3 has attracted more attention recently because of its possibly induced novel polar states and related paraelectric-ferroelectric phase transitions. By using controlled pulsed laser deposition, high-quality, ultrathin, and strained SrTiO3 layers were obtained. Here, transmission electron microscopy and theoretical simulations have unveiled highly polar states in SrTiO3 films even down to one unit cell at room temperature, which were stabilized in the PbTiO3/SrTiO3/PbTiO3 sandwich structures by in-plane tensile strain and interfacial coupling, as evidenced by large tetragonality (∼1.05), notable polar ion displacement (0.019 nm), and thus ultrahigh spontaneous polarization (up to ∼50 µC/cm2). These values are nearly comparable to those of the strong ferroelectrics as the PbZrxTi1-xO3 family. Our findings provide an effective and practical approach for integrating large strain states into oxide films and inducing polarization in nonpolar materials, which may broaden the functionality of nonpolar oxides and pave the way for the discovery of new electronic materials.

4.
J Neurochem ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38533619

RESUMO

Though previous studies revealed the potential associations of elevated levels of plasma fibrinogen with dementia, there is still limited understanding regarding the influence of Alzheimer's disease (AD) biomarkers on these associations. We sought to investigate the interrelationships among fibrinogen, cerebrospinal fluid (CSF) AD biomarkers, and cognition in non-demented adults. We included 1996 non-demented adults from the Chinese Alzheimer's Biomarker and LifestylE (CABLE) study and 337 from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. The associations of fibrinogen with AD biomarkers and cognition were explored using multiple linear regression models. The mediation analyses with 10 000 bootstrapped iterations were conducted to explore the mediating effects of AD biomarkers on cognition. In addition, interaction analyses and subgroup analyses were conducted to assess the influence of covariates on the relationships between fibrinogen and AD biomarkers. Participants exhibiting low Aß42 were designated as A+, while those demonstrating high phosphorylated tau (P-tau) and total tau (Tau) were labeled as T+ and N+, respectively. Individuals with normal measures of Aß42 and P-tau were categorized as the A-T- group, and those with abnormal levels of both Aß42 and P-tau were grouped under A+T+. Fibrinogen was higher in the A+ subgroup compared to that in the A- subgroup (p = 0.026). Fibrinogen was higher in the A+T+ subgroup compared to that in the A-T- subgroup (p = 0.011). Higher fibrinogen was associated with worse cognition and Aß pathology (all p < 0.05). Additionally, the associations between fibrinogen and cognition were partially mediated by Aß pathology (mediation proportion range 8%-28%). Interaction analyses and subgroup analyses showed that age and ApoE ε4 affect the relationships between fibrinogen and Aß pathology. Fibrinogen was associated with both cognition and Aß pathology. Aß pathology may be a critical mediator for impacts of fibrinogen on cognition.

5.
Small ; : e2312218, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38716754

RESUMO

Room-temperature phosphorescent materials, renowned for their long luminescence lifetimes, have garnered significant attention in the field of optical materials. However, the challenges posed by thermally induced quenching have significantly hindered the advancement of luminescence efficiency and stability. In this study, thermally enhanced phosphorescent carbon nanodots (CND) are developed by incorporating them into fiber matrices. Remarkably, the phosphorescence lifetime of the thermally enhanced CND exhibits a twofold enhancement, increasing from 326 to 753 ms, while the phosphorescence intensity experienced a tenfold enhancement, increasing from 25 to 245 as the temperature increased to 373 K. Rigid fiber matrices can effectively suppress the non-radiative transition rate of triplet excitons, while high temperatures can desorb oxygen adsorbed on the surface of the CND, disrupting the interaction between the CND and oxygen. Consequently, a thermally enhanced phosphorescence is obtained. In addition, benefiting from the thermally enhanced phosphorescence property of CND, a warning indicator with an anti-counterfeiting function for monitoring cold-chain logistics is demonstrated based on CND.

6.
J Transl Med ; 22(1): 598, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937806

RESUMO

BACKGROUND: Monocyte-derived alveolar macrophages (Mo_AMs) are increasingly recognised as potential pathogenic factors for idiopathic pulmonary fibrosis (IPF). While scRNAseq analysis has proven valuable in the transcriptome profiling of Mo_AMs, the integration analysis of multi-omics may provide additional dimensions of understanding of these cellular populations. METHODS: We performed multi-omics analysis on 116 scRNAseq, 119 bulkseq and five scATACseq lung tissue samples from IPF. We built a large-scale IPF scRNAseq atlas and conducted the Monocle 2/3 as well as the Cellchat to explore the developmental path and intercellular communication on Mo_AMs. We also reported the difference in metabolisms, tissue repair and phagocytosis between Mo_AMs and tissue-resident alveolar macrophages (TRMs). To determine whether Mo_AMs affected pulmonary function, we projected clinical phenotypes (FVC%pred) from the bulkseq dataset onto the scRNAseq atlas. Finally, we used scATATCseq to uncover the upstream regulatory mechanisms and determine key drivers in Mo_AMs. RESULTS: We identified three Mo_AMs clusters and the trajectory analysis further validated the origin of these clusters. Moreover, via the Cellchat analysis, the CXCL12/CXCR4 axis was found to be involved in the molecular basis of reciprocal interactions between Mo_AMs and fibroblasts through the activation of the ERK pathway in Mo_AMs. SPP1_RecMacs (RecMacs, recruited macrophages) were higher in the low-FVC group than in the high-FVC group. Specifically, compared with TRMs, the functions of lipid and energetic metabolism as well as tissue repair were higher in Mo_AMs than TRMs. But, TRMs may have higher level of phagocytosis than TRMs. SPIB (PU.1), JUNB, JUND, BACH2, FOSL2, and SMARCC1 showed stronger association with open chromatin of Mo_AMs than TRMs. Significant upregulated expression and deep chromatin accessibility of APOE were observed in both SPP1_RecMacs and TRMs. CONCLUSION: Through trajectory analysis, it was confirmed that SPP1_RecMacs derived from Monocytes. Besides, Mo_AMs may influence FVC% pred and aggravate pulmonary fibrosis through the communication with fibroblasts. Furthermore, distinctive transcriptional regulators between Mo_AMs and TRMs implied that they may depend on different upstream regulatory mechanisms. Overall, this work provides a global overview of how Mo_AMs govern IPF and also helps determine better approaches and intervention therapies.


Assuntos
Fibrose Pulmonar Idiopática , Macrófagos Alveolares , Monócitos , Humanos , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/genética , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/patologia , Monócitos/metabolismo , Masculino , Perfilação da Expressão Gênica , Feminino , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Pessoa de Meia-Idade , Fenótipo , Pulmão/patologia , Pulmão/metabolismo , Regulação da Expressão Gênica
7.
J Hum Genet ; 69(5): 197-203, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38374166

RESUMO

CAPZA2 encodes the α2 subunit of CAPZA, which is vital for actin polymerization and depolymerization in humans. However, understanding of diseases associated with CAPZA2 remains limited. To date, only three cases have been documented with neurodevelopmental abnormalities such as delayed motor development, speech delay, intellectual disability, hypotonia, and a history of seizures. In this study, we document a patient who exhibited seizures, mild intellectual disability, and impaired motor development yet did not demonstrate speech delay or hypotonia. The patient also suffered from recurrent instances of respiratory infections, gastrointestinal and allergic diseases. A novel de novo splicing variant c.219+1 G > A was detected in the CAPZA2 gene through whole-exome sequencing. This variant led to exon 4 skipping in mRNA splicing, confirmed by RT-PCR and Sanger sequencing. To our knowledge, this is the third study on human CAPZA2 defects, documenting the fourth unambiguously diagnosed case. Furthermore, this splicing mutation type is reported here for the first time. Our research offers additional support for the existence of a CAPZA2-related non-syndromic neurodevelopmental disorder. Our findings augment our understanding of the phenotypic range associated with CAPZA2 deficiency and enrich the knowledge of the mutational spectrum of the CAPZA2 gene.


Assuntos
Proteína de Capeamento de Actina CapZ , Deficiências do Desenvolvimento , Epilepsia , Heterozigoto , Hipotonia Muscular , Mutação , Pré-Escolar , Feminino , Humanos , Masculino , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Epilepsia/genética , Sequenciamento do Exoma , Deficiência Intelectual/genética , Deficiência Intelectual/patologia , Hipotonia Muscular/genética , Hipotonia Muscular/patologia , Fenótipo , Splicing de RNA/genética , Proteína de Capeamento de Actina CapZ/genética
8.
Opt Express ; 32(1): 785-794, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175098

RESUMO

Cavity optomechanical (COM) entanglement, playing an essential role in building quantum networks and enhancing quantum sensors, is usually weak and easily destroyed by noises. As feasible and effective ways to overcome this obstacle, optical or mechanical parametric modulations have been used to improve the quality of quantum squeezing or entanglement in various COM systems. However, the possibility of combining these powerful means to enhance COM entanglement has yet to be explored. Here, we fill this gap by studying a COM system containing an intra-cavity optical parametric amplifier (OPA), driven optically and mechanically. By tuning the relative strength and the frequency mismatch of optical and mechanical driving fields, we find that constructive interference can emerge and significantly improve the strength of COM entanglement and its robustness to thermal noises. This work sheds what we believe to be a new light on preparing and protecting quantum states with multi-field driven COM systems for diverse applications.

9.
Opt Express ; 32(12): 22020-22030, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859542

RESUMO

We propose how to achieve chiral photon blockade by spinning a nonlinear optical resonator. We show that by driving such a device at a fixed direction, completely different quantum effects can emerge for the counter-propagating optical modes, due to the spinning-induced breaking of time-reversal symmetry, which otherwise is unattainable for the same device in the static regime. Also, we find that in comparison with the static case, robust non-classical correlations against random backscattering losses can be achieved for such a quantum chiral system. Our work, extending previous works on the spontaneous breaking of optical chiral symmetry from the classical to purely quantum regimes, can stimulate more efforts towards making and utilizing various chiral quantum effects, including applications for chiral quantum networks or noise-tolerant quantum sensors.

10.
Scand J Immunol ; 100(3): e13393, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38922971

RESUMO

It is urgent to explore factors affecting immunotherapy efficacy to benefit non-small cell lung cancer (NSCLC) patient survival. Bioinformatics predicted genes associated with programmed cell death ligand 1 (PD-L1) expression and analysed phospholipase A2 group IID (PLA2G2D) expression in NSCLC. BODIPY 493/503 dye staining and kits detected lipids, triglycerides, and phospholipids in H1299 cells, respectively. Extracellular vesicles (EVs) were extracted for morphology and size assessment using electron microscopy. Western blot assayed CD9, CD63, HSP90, EVs-PD-L1, PD-L1, and PLA2G2D expression. CCK-8, LDH, and ELISA tested proliferation and toxicity of CD8+ T cells, interleukin-2, and interferon-gamma secretion, respectively. PLA2G2D, PD-L1, and Ki67 expression was detected by immunohistochemistry. Immunofluorescence assayed PLA2G2D localisation and CD8+ T cell content. Flow cytometry assessed PD-L1 and CD8 expression. In NSCLC, upregulated EVs-PD-L1 and clinical characteristics showed a strong correlation. H1299 cells with overexpression PD-L1 significantly reduced proliferation, toxicity of CD8+ T cells, and interleukin-2 and interferon-gamma levels. Bioinformatics revealed positive correlations between PLA2G2D and overexpressed PD-L1. PLA2G2D was expressed in macrophages and dendritic cells in NSCLC tissue. Overexpression PLA2G2D (oe-PLA2G2D) increased lipids, triglycerides, and phospholipids contents in H1299 cells. oe-PLA2G2D significantly reduced proliferation, toxicity of CD8+ T cells, and interleukin-2 and interferon-gamma levels. si-PD-L1 restored inhibition of oe-PLA2G2D on CD8+ T cells. oe-PLA2G2D significantly increased mice tumour volume and weight, upregulated expression of blood EVs-PD-L1 and tissue PD-L1, PLA2G2D, Ki67, and decreased CD8+ T cell content. PLA2G2D facilitated immune escape in NSCLC by regulating CD8+ T cell immune function by upregulating EVs-PD-L1.


Assuntos
Antígeno B7-H1 , Linfócitos T CD8-Positivos , Carcinoma Pulmonar de Células não Pequenas , Vesículas Extracelulares , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/imunologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Humanos , Antígeno B7-H1/metabolismo , Neoplasias Pulmonares/imunologia , Vesículas Extracelulares/imunologia , Vesículas Extracelulares/metabolismo , Animais , Camundongos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Evasão Tumoral/imunologia , Feminino , Masculino , Proliferação de Células , Pessoa de Meia-Idade
11.
Phys Rev Lett ; 133(4): 043601, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39121413

RESUMO

Realizing precise control over multiquanta emission is crucial for quantum information processing, especially when integrated with advanced techniques of manipulating quantum states. Here, by spinning the resonator to induce the Sagnac effect, we can obtain nonreciprocal photon-phonon and photon-magnon super-Rabi oscillations under conditions of optically driving resonance transitions. Opening dissipative channels for such super-Rabi oscillations enables the realization of directional bundle emissions of entangled photon-phonon pairs and photon-magnon pairs by transferring the pure multiquanta state to a bundled multiquanta outside of the system. This nonreciprocal emission is a flexible switch that can be controlled with precision, and simultaneous emissions of different entangled pairs (such as photon-phonon or photon-magnon pairs) can even emerge but in opposite directions by driving the resonator from different directions. This ability to flexibly manipulate the system allows us to achieve directional entangled multiquanta emitters, and has also potential applications for building hybrid quantum networks and on-chip quantum communications.

12.
BMC Cancer ; 24(1): 112, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254060

RESUMO

BACKGROUND: Since the Z0011 trial, the assessment of axillary lymph node status has been redirected from the previous assessment of the occurrence of lymph node metastasis alone to the assessment of the degree of lymph node loading. Our aim was to apply preoperative breast ultrasound and clinicopathological features to predict the diagnostic value of axillary lymph node load in early invasive breast cancer. METHODS: The 1247 lesions were divided into a high lymph node burden group and a limited lymph node burden group according to axillary lymph node status. Univariate and multifactorial analyses were used to predict the differences in clinicopathological characteristics and breast ultrasound characteristics between the two groups with high and limited lymph node burden. Pathological findings were used as the gold standard. RESULTS: Univariate analysis showed significant differences in ki-67, maximum diameter (MD), lesion distance from the nipple, lesion distance from the skin, MS, and some characteristic ultrasound features (P < 0.05). In multifactorial analysis, the ultrasound features of breast tumors that were associated with a high lymph node burden at the axilla included MD (odds ratio [OR], 1.043; P < 0.001), shape (OR, 2.422; P = 0.0018), hyperechoic halo (OR, 2.546; P < 0.001), shadowing in posterior features (OR, 2.155; P = 0.007), and suspicious lymph nodes on axillary ultrasound (OR, 1.418; P = 0.031). The five risk factors were used to build the predictive model, and it achieved an area under the receiver operating characteristic (ROC) curve (AUC) of 0.702. CONCLUSION: Breast ultrasound features and clinicopathological features are better predictors of high lymph node burden in early invasive breast cancer, and this prediction helps to develop more effective treatment plans.


Assuntos
Neoplasias da Mama , Neoplasias Mamárias Animais , Humanos , Feminino , Animais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Axila , Ultrassonografia Mamária , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia
13.
BMC Cancer ; 24(1): 409, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566057

RESUMO

BACKGROUND: Accurate evaluation of axillary lymph node metastasis (LNM) in breast cancer is very important. A large number of hyperplastic and dilated lymphangiogenesis cases can usually be found in the pericancerous tissue of breast cancer to promote the occurrence of tumor metastasis.Shear wave elastography (SWE) can be used as an important means for evaluating pericancerous stiffness. We determined the stiffness of the pericancerous by SWE to diagnose LNM and lymphangiogenesis in invasive breast cancer (IBC). METHODS: Patients with clinical T1-T2 stage IBC who received surgical treatment in our hospital from June 2020 to December 2020 were retrospectively enrolled. A total of 299 patients were eventually included in the preliminary study, which included an investigation of clinicopathological features, ultrasonic characteristics, and SWE parameters. Multivariable logistic regression analysis was used to establish diagnostic model and evaluated its diagnostic performance of LNM. The correlation among SWE values, collagen volume fraction (CVF), and microlymphatic density (MLD) in primary breast cancer lesions was analyzed in another 97 patients. RESULTS: The logistic regression model is Logit(P)=-1.878 + 0.992*LVI-2.010*posterior feature enhancement + 1.230*posterior feature shadowing + 0.102*posterior feature combined pattern + 0.009*Emax. The optimum cutoff value of the logistic regression model was 0.365, and the AUC (95% CI) was 0.697 (0.636-0.758); the sensitivity (70.7 vs. 54.3), positive predictive value (PPV) (54.0 vs. 50.8), negative predictive value (NPV) (76.9 vs. 69.7), and accuracy (65.2 vs. 61.9) were all higher than Emax. There was no correlation between the SWE parameters and MLD in primary breast cancer lesions. CONCLUSIONS: The logistic regression model can help us to determine LNM, thus providing more imaging basis for the selection of preoperative treatment. The SWE parameter of the primary breast cancer lesion cannot reflect the peritumoral lymphangiogenesis, and we still need to find a new ultrasonic imaging method.


Assuntos
Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Humanos , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Linfangiogênese , Metástase Linfática/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Estudos Retrospectivos
14.
J Org Chem ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39135492

RESUMO

Thioesters make up an important class of bioactive compounds. Due to their chemoselectivity, they have been widely used in the synthesis of a wide range of complex bioactive molecules and natural products. At present, chemists have developed a variety of methods for the preparation of thioester compounds. However, these methods usually require the use of transition metal catalysis or harsh reaction conditions. The strategy of synthesizing thioester compounds via visible light-induced electron donor-acceptor (EDA) complex reactions avoids the problems associated with conventional methods through the development of photocatalysis. Here we report a sustainable method for thiocarbonylating aryl sulfonium salts via a visible light-induced EDA complex process without transition metals.

15.
J Org Chem ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138971

RESUMO

On the basis of a novel umpolung strategy, an efficient l-amino acid ester-mediated in situ reduction of 2-(2-oxoindolin-3-ylidene)malononitrile and sequential nucleophilic addition/cyclization cascade reaction is reported. Various densely substituted cyclopentene bispirooxindoles and dihydrofuran bispirooxindoles with two quaternary spirocenters were constructed in high yields (≤93%) with excellent diastereoselectivities (>20:1 dr). The method has advantages of readily available starting materials, mild reaction conditions, a one-pot process, a metal-free biomimetic reducing agent, a wide substrate scope, and operational simplicity (single filtration without column chromatography).

16.
Nature ; 558(7711): 569-572, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29950624

RESUMO

Creating optical components that allow light to propagate in only one direction-that is, that allow non-reciprocal propagation or 'isolation' of light-is important for a range of applications. Non-reciprocal propagation of sound can be achieved simply by using mechanical components that spin1,2. Spinning also affects de Broglie waves 3 , so a similar idea could be applied in optics. However, the extreme rotation rates that would be required, owing to light travelling much faster than sound, lead to unwanted wobbling. This wobbling makes it difficult to maintain the separation between the spinning devices and the couplers to within tolerance ranges of several nanometres, which is essential for critical coupling4,5. Consequently, previous applications of optical6-17 and optomechanical10,17-20 isolation have used alternative methods. In hard-drive technology, the magnetic read heads of a hard-disk drive fly aerodynamically above the rapidly rotating disk with nanometre precision, separated by a thin film of air with near-zero drag that acts as a lubrication layer 21 . Inspired by this, here we report the fabrication of photonic couplers (tapered fibres that couple light into the resonators) that similarly fly above spherical resonators with a separation of only a few nanometres. The resonators spin fast enough to split their counter-circulating optical modes, making the fibre coupler transparent from one side while simultaneously opaque from the other-that is, generating irreversible transmission. Our setup provides 99.6 per cent isolation of light in standard telecommunication fibres, of the type used for fibre-based quantum interconnects 22 . Unlike flat geometries, such as between a magnetic head and spinning disk, the saddle-like, convex geometry of the fibre and sphere in our setup makes it relatively easy to bring the two closer together, which could enable surface-science studies at nanometre-scale separations.

17.
Acta Pharmacol Sin ; 45(7): 1477-1491, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38538716

RESUMO

Refractory wounds are a severe complication of diabetes mellitus that often leads to amputation because of the lack of effective treatments and therapeutic targets. The pathogenesis of refractory wounds is complex, involving many types of cells. Rho-associated protein kinase-1 (ROCK1) phosphorylates a series of substrates that trigger downstream signaling pathways, affecting multiple cellular processes, including cell migration, communication, and proliferation. The present study investigated the role of ROCK1 in diabetic wound healing and molecular mechanisms. Our results showed that ROCK1 expression significantly increased in wound granulation tissues in diabetic patients, streptozotocin (STZ)-induced diabetic mice, and db/db diabetic mice. Wound healing and blood perfusion were dose-dependently improved by the ROCK1 inhibitor fasudil in diabetic mice. In endothelial cells, fasudil and ROCK1 siRNA significantly elevated the phosphorylation of adenosine monophosphate-activated protein kinase at Thr172 (pThr172-AMPKα), the activity of endothelial nitric oxide synthase (eNOS), and suppressed the levels of mitochondrial reactive oxygen species (mtROS) and nitrotyrosine formation. Experiments using integrated bioinformatics analysis and coimmunoprecipitation established that ROCK1 inhibited pThr172-AMPKα by binding to receptor-interacting serine/threonine kinase 4 (RIPK4). These results suggest that fasudil accelerated wound repair and improved angiogenesis at least partially through the ROCK1/RIPK4/AMPK pathway. Fasudil may be a potential treatment for refractory wounds in diabetic patients.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina , Diabetes Mellitus Experimental , Transdução de Sinais , Cicatrização , Quinases Associadas a rho , Animais , Quinases Associadas a rho/metabolismo , Quinases Associadas a rho/antagonistas & inibidores , Cicatrização/efeitos dos fármacos , Humanos , Diabetes Mellitus Experimental/metabolismo , Masculino , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/uso terapêutico , Camundongos , Transdução de Sinais/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por AMP/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Células Endoteliais da Veia Umbilical Humana , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/metabolismo , Feminino
18.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34607960

RESUMO

Human genetic studies have pointed to a prominent role for innate immunity and lipid pathways in immunological and neurodegenerative disorders. Our understanding of the composition and function of immunomodulatory lipid networks in innate immune cells, however, remains incomplete. Here, we show that phospholipase Cγ2 (PLCγ2 or PLCG2)-mutations in which are associated with autoinflammatory disorders and Alzheimer's disease-serves as a principal source of diacylglycerol (DAG) pools that are converted into a cascade of bioactive endocannabinoid and eicosanoid lipids by DAG lipase (DAGL) and monoacylglycerol lipase (MGLL) enzymes in innate immune cells. We show that this lipid network is tonically stimulated by disease-relevant human mutations in PLCγ2, as well as Fc receptor activation in primary human and mouse macrophages. Genetic disruption of PLCγ2 in mouse microglia suppressed DAGL/MGLL-mediated endocannabinoid-eicosanoid cross-talk and also caused widespread transcriptional and proteomic changes, including the reorganization of immune-relevant lipid pathways reflected in reductions in DAGLB and elevations in PLA2G4A. Despite these changes, Plcg2-/- mice showed generally normal proinflammatory cytokine and chemokine responses to lipopolysaccharide treatment, instead displaying a more restricted deficit in microglial activation that included impairments in prostaglandin production and CD68 expression. Our findings enhance the understanding of PLCγ2 function in innate immune cells, delineating a role in cross-talk with endocannabinoid/eicosanoid pathways and modulation of subsets of cellular responses to inflammatory stimuli.


Assuntos
Eicosanoides/metabolismo , Endocanabinoides/metabolismo , Imunidade Inata/imunologia , Macrófagos/imunologia , Fosfolipase C gama/metabolismo , Animais , Antígenos CD/biossíntese , Antígenos de Diferenciação Mielomonocítica/biossíntese , Células COS , Linhagem Celular , Chlorocebus aethiops , Citocinas/imunologia , Diglicerídeos/metabolismo , Fosfolipases A2 do Grupo IV/metabolismo , Células HEK293 , Humanos , Inflamação/imunologia , Lipopolissacarídeos/imunologia , Lipase Lipoproteica/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/imunologia , Monoacilglicerol Lipases/metabolismo , Fosfolipase C gama/genética , Prostaglandinas/biossíntese , Receptores Fc/imunologia , Transdução de Sinais/imunologia
19.
Proc Natl Acad Sci U S A ; 118(14)2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33785600

RESUMO

The contraction of heart cells is controlled by the intermolecular signaling between L-type Ca2+ channels (LCCs) and ryanodine receptors (RyRs), and the nanodistance between them depends on the interaction between junctophilin-2 (JPH2) in the sarcoplasmic reticulum (SR) and caveolin-3 (CAV3) in the transversal tubule (TT). In heart failure, decreased expression of JPH2 compromises LCC-RyR communication leading to deficient blood-pumping power. In the present study, we found that JPH2 and CAV3 transcription was concurrently regulated by serum response factor (SRF) and myocardin. In cardiomyocytes from torpid ground squirrels, compared with those from euthermic counterparts, myocardin expression was up-regulated, which boosted both JPH2 and CAV3 expression. Transmission electron microscopic imaging showed that the physical coupling between TTs and SRs was tightened during hibernation and after myocardin overexpression. Confocal Ca2+ imaging under the whole-cell patch clamp condition revealed that these changes enhanced the efficiency of LCC-RyR intermolecular signaling and fully compensated the adaptive down-regulation of LCCs, maintaining the power of heart contraction while avoiding the risk of calcium overload during hibernation. Our finding not only revealed an essential molecular mechanism underlying the survival of hibernating mammals, but also demonstrated a "reverse model of heart failure" at the molecular level, suggesting a strategy for treating heart diseases.


Assuntos
Sinalização do Cálcio , Hibernação , Miócitos Cardíacos/metabolismo , Animais , Caveolinas/genética , Caveolinas/metabolismo , Células Cultivadas , Acoplamento Excitação-Contração , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Nucleares/sangue , Proteínas Nucleares/metabolismo , Sciuridae , Transativadores/sangue , Transativadores/metabolismo
20.
J Med Internet Res ; 26: e58599, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042442

RESUMO

BACKGROUND: Diagnosing underlying causes of nonneurogenic male lower urinary tract symptoms associated with bladder outlet obstruction (BOO) is challenging. Video-urodynamic studies (VUDS) and pressure-flow studies (PFS) are both invasive diagnostic methods for BOO. VUDS can more precisely differentiate etiologies of male BOO, such as benign prostatic obstruction, primary bladder neck obstruction, and dysfunctional voiding, potentially outperforming PFS. OBJECTIVE: These examinations' invasive nature highlights the need for developing noninvasive predictive models to facilitate BOO diagnosis and reduce the necessity for invasive procedures. METHODS: We conducted a retrospective study with a cohort of men with medication-refractory, nonneurogenic lower urinary tract symptoms suspected of BOO who underwent VUDS from 2001 to 2022. In total, 2 BOO predictive models were developed-1 based on the International Continence Society's definition (International Continence Society-defined bladder outlet obstruction; ICS-BOO) and the other on video-urodynamic studies-diagnosed bladder outlet obstruction (VBOO). The patient cohort was randomly split into training and test sets for analysis. A total of 6 machine learning algorithms, including logistic regression, were used for model development. During model development, we first performed development validation using repeated 5-fold cross-validation on the training set and then test validation to assess the model's performance on an independent test set. Both models were implemented as paper-based nomograms and integrated into a web-based artificial intelligence prediction tool to aid clinical decision-making. RESULTS: Among 307 patients, 26.7% (n=82) met the ICS-BOO criteria, while 82.1% (n=252) were diagnosed with VBOO. The ICS-BOO prediction model had a mean area under the receiver operating characteristic curve (AUC) of 0.74 (SD 0.09) and mean accuracy of 0.76 (SD 0.04) in development validation and AUC and accuracy of 0.86 and 0.77, respectively, in test validation. The VBOO prediction model yielded a mean AUC of 0.71 (SD 0.06) and mean accuracy of 0.77 (SD 0.06) internally, with AUC and accuracy of 0.72 and 0.76, respectively, externally. When both models' predictions are applied to the same patient, their combined insights can significantly enhance clinical decision-making and simplify the diagnostic pathway. By the dual-model prediction approach, if both models positively predict BOO, suggesting all cases actually resulted from medication-refractory primary bladder neck obstruction or benign prostatic obstruction, surgical intervention may be considered. Thus, VUDS might be unnecessary for 100 (32.6%) patients. Conversely, when ICS-BOO predictions are negative but VBOO predictions are positive, indicating varied etiology, VUDS rather than PFS is advised for precise diagnosis and guiding subsequent therapy, accurately identifying 51.1% (47/92) of patients for VUDS. CONCLUSIONS: The 2 machine learning models predicting ICS-BOO and VBOO, based on 6 noninvasive clinical parameters, demonstrate commendable discrimination performance. Using the dual-model prediction approach, when both models predict positively, VUDS may be avoided, assisting in male BOO diagnosis and reducing the need for such invasive procedures.


Assuntos
Nomogramas , Obstrução do Colo da Bexiga Urinária , Urodinâmica , Humanos , Obstrução do Colo da Bexiga Urinária/diagnóstico , Obstrução do Colo da Bexiga Urinária/fisiopatologia , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Inteligência Artificial
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