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1.
Nature ; 610(7933): 661-666, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36198794

RESUMEN

Networks of optical clocks find applications in precise navigation1,2, in efforts to redefine the fundamental unit of the 'second'3-6 and in gravitational tests7. As the frequency instability for state-of-the-art optical clocks has reached the 10-19 level8,9, the vision of a global-scale optical network that achieves comparable performances requires the dissemination of time and frequency over a long-distance free-space link with a similar instability of 10-19. However, previous attempts at free-space dissemination of time and frequency at high precision did not extend beyond dozens of kilometres10,11. Here we report time-frequency dissemination with an offset of 6.3 × 10-20 ± 3.4 × 10-19 and an instability of less than 4 × 10-19 at 10,000 s through a free-space link of 113 km. Key technologies essential to this achievement include the deployment of high-power frequency combs, high-stability and high-efficiency optical transceiver systems and efficient linear optical sampling. We observe that the stability we have reached is retained for channel losses up to 89 dB. The technique we report can not only be directly used in ground-based applications, but could also lay the groundwork for future satellite time-frequency dissemination.

2.
Nature ; 589(7841): 214-219, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33408416

RESUMEN

Quantum key distribution (QKD)1,2 has the potential to enable secure communication and information transfer3. In the laboratory, the feasibility of point-to-point QKD is evident from the early proof-of-concept demonstration in the laboratory over 32 centimetres4; this distance was later extended to the 100-kilometre scale5,6 with decoy-state QKD and more recently to the 500-kilometre scale7-10 with measurement-device-independent QKD. Several small-scale QKD networks have also been tested outside the laboratory11-14. However, a global QKD network requires a practically (not just theoretically) secure and reliable QKD network that can be used by a large number of users distributed over a wide area15. Quantum repeaters16,17 could in principle provide a viable option for such a global network, but they cannot be deployed using current technology18. Here we demonstrate an integrated space-to-ground quantum communication network that combines a large-scale fibre network of more than 700 fibre QKD links and two high-speed satellite-to-ground free-space QKD links. Using a trusted relay structure, the fibre network on the ground covers more than 2,000 kilometres, provides practical security against the imperfections of realistic devices, and maintains long-term reliability and stability. The satellite-to-ground QKD achieves an average secret-key rate of 47.8 kilobits per second for a typical satellite pass-more than 40 times higher than achieved previously. Moreover, its channel loss is comparable to that between a geostationary satellite and the ground, making the construction of more versatile and ultralong quantum links via geosynchronous satellites feasible. Finally, by integrating the fibre and free-space QKD links, the QKD network is extended to a remote node more than 2,600 kilometres away, enabling any user in the network to communicate with any other, up to a total distance of 4,600 kilometres.

3.
Nature ; 582(7813): 501-505, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32541968

RESUMEN

Quantum key distribution (QKD)1-3 is a theoretically secure way of sharing secret keys between remote users. It has been demonstrated in a laboratory over a coiled optical fibre up to 404 kilometres long4-7. In the field, point-to-point QKD has been achieved from a satellite to a ground station up to 1,200 kilometres away8-10. However, real-world QKD-based cryptography targets physically separated users on the Earth, for which the maximum distance has been about 100 kilometres11,12. The use of trusted relays can extend these distances from across a typical metropolitan area13-16 to intercity17 and even intercontinental distances18. However, relays pose security risks, which can be avoided by using entanglement-based QKD, which has inherent source-independent security19,20. Long-distance entanglement distribution can be realized using quantum repeaters21, but the related technology is still immature for practical implementations22. The obvious alternative for extending the range of quantum communication without compromising its security is satellite-based QKD, but so far satellite-based entanglement distribution has not been efficient23 enough to support QKD. Here we demonstrate entanglement-based QKD between two ground stations separated by 1,120 kilometres at a finite secret-key rate of 0.12 bits per second, without the need for trusted relays. Entangled photon pairs were distributed via two bidirectional downlinks from the Micius satellite to two ground observatories in Delingha and Nanshan in China. The development of a high-efficiency telescope and follow-up optics crucially improved the link efficiency. The generated keys are secure for realistic devices, because our ground receivers were carefully designed to guarantee fair sampling and immunity to all known side channels24,25. Our method not only increases the secure distance on the ground tenfold but also increases the practical security of QKD to an unprecedented level.

4.
Proc Natl Acad Sci U S A ; 120(34): e2302603120, 2023 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-37579161

RESUMEN

Certain transmembrane and membrane-tethered signaling proteins export from cilia as BBSome cargoes via the outward BBSome transition zone (TZ) diffusion pathway, indispensable for maintaining their ciliary dynamics to enable cells to sense and transduce extracellular stimuli inside the cell. Murine Rab-like 2 (Rabl2) GTPase resembles Chlamydomonas Arf-like 3 (ARL3) GTPase in promoting outward TZ passage of the signaling protein cargo-laden BBSome. During this process, ARL3 binds to and recruits the retrograde IFT train-dissociated BBSome as its effector to diffuse through the TZ for ciliary retrieval, while how RABL2 and ARL3 cross talk in this event remains uncertain. Here, we report that Chlamydomonas RABL2 in a GTP-bound form (RABL2GTP) cycles through cilia via IFT as an IFT-B1 cargo, dissociates from retrograde IFT trains at a ciliary region right above the TZ, and converts to RABL2GDP for activating ARL3GDP as an ARL3 guanine nucleotide exchange factor. This confers ARL3GTP to detach from the ciliary membrane and become available for binding and recruiting the phospholipase D (PLD)-laden BBSome, autonomous of retrograde IFT association, to diffuse through the TZ for ciliary retrieval. Afterward, RABL2GDP exits cilia by being bound to the ARL3GTP/BBSome entity as a BBSome cargo. Our data identify ciliary signaling proteins exported from cilia via the RABL2-ARL3 cascade-mediated outward BBSome TZ diffusion pathway. According to this model, hedgehog signaling defect-induced Bardet-Biedl syndrome caused by RABL2 mutations in humans could be well explained in a mutation-specific manner, providing us with a mechanistic understanding behind the outward BBSome TZ passage required for proper ciliary signaling.


Asunto(s)
Cilios , Proteínas Hedgehog , Humanos , Factores de Ribosilacion-ADP/genética , Factores de Ribosilacion-ADP/metabolismo , Cilios/metabolismo , GTP Fosfohidrolasas/metabolismo , Guanosina Trifosfato/metabolismo , Proteínas Hedgehog/metabolismo , Proteínas de la Membrana/metabolismo , Transporte de Proteínas/genética , Proteínas de Unión al GTP rab/metabolismo , Chlamydomonas
5.
Ann Neurol ; 96(1): 87-98, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38661228

RESUMEN

OBJECTIVE: Exposure to heavy metals has been reported to be associated with impaired cognitive function, but the underlying mechanisms remain unclear. This pilot study aimed to identify key heavy metal elements associated with cognitive function and further explore the potential mediating role of metal-related DNA methylation. METHODS: Blood levels of arsenic, cadmium, lead, copper, manganese, and zinc and genome-wide DNA methylations were separately detected in peripheral blood in 155 older adults. Cognitive function was evaluated using the Mini-Mental State Examination (MMSE). Least absolute shrinkage and selection operator penalized regression and Bayesian kernel machine regression were used to identify metals associated with cognitive function. An epigenome-wide association study examined the DNA methylation profile of the identified metal, and mediation analysis investigated its mediating role. RESULTS: The MMSE scores showed a significant decrease of 1.61 (95% confidence interval [CI]: -2.64, -0.59) with each 1 standard deviation increase in ln-transformed arsenic level; this association was significant in multiple-metal models and dominated the overall negative effect of 6 heavy metal mixture on cognitive function. Seventy-three differentially methylated positions were associated with blood arsenic (p < 1.0 × 10-5). The methylation levels at cg05226051 (annotated to TDRD3) and cg18886932 (annotated to GAL3ST3) mediated 24.8% and 25.5% of the association between blood arsenic and cognitive function, respectively (all p < 0.05). INTERPRETATION: Blood arsenic levels displayed a negative association with the cognitive function of older adults. This finding shows that arsenic-related DNA methylation alterations are critical partial mediators that may serve as potential biomarkers for further mechanism-related studies. ANN NEUROL 2024;96:87-98.


Asunto(s)
Cognición , Metilación de ADN , Epigenoma , Análisis de Mediación , Metales Pesados , Humanos , Metilación de ADN/efectos de los fármacos , Metilación de ADN/genética , Femenino , Masculino , Metales Pesados/sangre , Anciano , Cognición/efectos de los fármacos , Epigenoma/genética , Proyectos Piloto , Arsénico/sangre , Arsénico/toxicidad , Estudio de Asociación del Genoma Completo , Persona de Mediana Edad , Disfunción Cognitiva/genética , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/sangre , Anciano de 80 o más Años , Pruebas de Estado Mental y Demencia
6.
Exp Cell Res ; 434(1): 113877, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38072302

RESUMEN

Exploration of the molecular mechanisms of mesenchymal stem cell (MSC) growth has significant clinical benefits. Long non-coding RNAs (lncRNAs) have been reported to play vital roles in the regulation of the osteogenic differentiation of MSCs. However, the mechanism by which lncRNA affects the proliferation and apoptosis of MSCs is unclear. In this study, sequencing analysis revealed that LINC00707 was significantly decreased in non-adherent human MSCs (non-AC-hMSCs) compared to adherent human MSCs. Moreover, LINC00707 overexpression promoted non-AChMSC proliferation, cell cycle progression from the G0/G1 phase to the S phase and inhibited apoptosis, whereas LINC00707 silencing had the opposite effect. Furthermore, LINC00707 interacted directly with the quaking (QKI) protein and enhanced the E3 ubiquitin-protein ligase ring finger protein 6 (RNF6)-mediated ubiquitination of the QKI protein. Additionally, the overexpression of QKI rescued the promotive effects on proliferation and inhibitory effects on apoptosis in non-AC-hMSCs induced by the ectopic expression of LINC00707. Thus, LINC00707 contributes to the proliferation and apoptosis in non-AChMSCs by regulating the ubiquitination and degradation of the QKI protein.


Asunto(s)
Células Madre Mesenquimatosas , ARN Largo no Codificante , Humanos , Osteogénesis/genética , Proliferación Celular/genética , Apoptosis/genética , Células Madre Mesenquimatosas/metabolismo , Ubiquitinación , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ARN/metabolismo
7.
Proc Natl Acad Sci U S A ; 119(36): e2207963119, 2022 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-36037363

RESUMEN

The filamentous, multicellular cyanobacterium Anabaena sp. PCC 7120 (Anabaena) is a prokaryotic model for the study of cell differentiation and cell-cell interactions. Upon combined-nitrogen deprivation, Anabaena forms a particular cell type, heterocyst, for aerobic nitrogen fixation. Heterocysts are semiregularly spaced among vegetative cells. Heterocyst differentiation is coupled to cell division, but the underlying mechanism remains unclear. This mechanism could be mediated by the putative protease HetF, which is a divisome component and is necessary for heterocyst differentiation. In this study, by suppressor screening, we identified PatU3, as a negative regulator acting downstream of HetF for cell division and heterocyst development. The inactivation of patU3 restored the capacity of cell division and heterocyst differentiation in the ΔhetF mutant, and overexpression of patU3 inhibited both processes in the wild-type background. We demonstrated that PatU3 was a specific substrate of the protease activity of HetF. Consequently, PatU3 accumulated in the hetF-deficient mutant, which was responsible for the resultant mutant phenotype. The cleavage site of PatU3 by HetF was mapped after the Arg117 residue, whose mutation made PatU3 resistant to HetF processing, and mimicked the effect of hetF deletion. Our results provided evidence that HetF regulated cell division and heterocyst differentiation by controlling the inhibitory effects of PatU3. This proteolytic pathway constituted a mechanism for the coordination between cell division and differentiation in a prokaryotic model used for studies on developmental biology and multicellularity.


Asunto(s)
Anabaena , Proteínas Bacterianas , División Celular , Proteolisis , Anabaena/citología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica
8.
Nano Lett ; 24(4): 1341-1350, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38252869

RESUMEN

In situ drug synthesis using the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction has attracted considerable attention in tumor therapy because of its satisfactory effectiveness and reduced side-effects. However, the exogenous addition of copper catalysts can cause cytotoxicity and has hampered biomedical applications in vivo. Here, we design and synthesize a metal-organic framework (MOF) to mimic copper chaperone, which can selectively modulate copper trafficking for bioorthogonal synthesis with no need of exogenous addition of copper catalysts. Like copper chaperones, the prepared ZIF-8 copper chaperone mimics specifically bind copper ions through the formation of coordination bonds. Moreover, the copper is unloaded under the acidic environment due to the dissipation of the coordination interactions between metal ions and ligands. In this way, the cancer cell-targeted copper chaperone mimics can selectively transport copper ions into cells. Regulation of intracellular copper trafficking may inspire constructing bioorthogonal catalysis system with reduced metal cytotoxicity in live cells.


Asunto(s)
Alquinos , Cobre , Cobre/farmacología , Cobre/química , Alquinos/química , Azidas/química , Reacción de Cicloadición , Catálisis , Iones
9.
Nano Lett ; 24(22): 6465-6473, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38767853

RESUMEN

Neutrophilic superhalide-anion-triggered chalcogen conversion-based Zn batteries, despite latent high-energy merit, usually suffer from a short lifespan caused by dendrite growth and shuttle effect. Here, a superhalide-anion-motivator reforming strategy is initiated to simultaneously manipulate the anode interface and Se conversion intermediates, realizing a bipolar regulation toward longevous energy-type Zn batteries. With ZnF2 chaotropic additives, the original large-radii superhalide zincate anion species in ionic liquid (IL) electrolytes are split into small F-containing species, boosting the formation of robust solid electrolyte interphases (SEI) for Zn dendrite inhibition. Simultaneously, ion radius reduced multiple F-containing Se conversion intermediates form, enhancing the interion interaction of charged products to suppress the shuttle effect. Consequently, Zn||Se batteries deliver a ca. 20-fold prolonged lifespan (2000 cycles) at 1 A g-1 and high energy/power density of 416.7 Wh kgSe-1/1.89 kW kgSe-1, outperforming those in F-free counterparts. Pouch cells with distinct plateaus and durable cyclability further substantiate the practicality of this design.

10.
BMC Genomics ; 25(1): 340, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575872

RESUMEN

BACKGROUND: The popularity of Muscovy ducks is attributed not only to their conformation traits but also to their slightly higher content of breast and leg meat, as well as their stronger-tasting meat compared to that of typical domestic ducks. However, there is a lack of comprehensive systematic research on the development of breast muscle in Muscovy ducks. In addition, since the number of skeletal muscle myofibers is established during the embryonic period, this study conducted a full-length transcriptome sequencing and microRNA sequencing of the breast muscle. Muscovy ducks at four developmental stages, namely Embryonic Day 21 (E21), Embryonic Day 27 (E27), Hatching Day (D0), and Post-hatching Day 7 (D7), were used to isolate total RNA for analysis. RESULTS: A total of 68,161 genes and 472 mature microRNAs were identified. In order to uncover deeper insights into the regulation of mRNA by miRNAs, we conducted an integration of the differentially expressed miRNAs (known as DEMs) with the differentially expressed genes (referred to as DEGs) across various developmental stages. This integration allowed us to make predictions regarding the interactions between miRNAs and mRNA. Through this analysis, we identified a total of 274 DEGs that may serve as potential targets for the 68 DEMs. In the predicted miRNA‒mRNA interaction networks, let-7b, miR-133a-3p, miR-301a-3p, and miR-338-3p were the hub miRNAs. In addition, multiple DEMs also showed predicted target relationships with the DEGs associated with skeletal system development. These identified DEGs and DEMs as well as their predicted interaction networks involved in the regulation of energy homeostasis and muscle development were most likely to play critical roles in facilitating the embryo-to-hatchling transition. A candidate miRNA, miR-301a-3p, exhibited increased expression during the differentiation of satellite cells and was downregulated in the breast muscle tissues of Muscovy ducks at E21 compared to E27. A dual-luciferase reporter assay suggested that the ANKRD1 gene, which encodes a transcription factor, is a direct target of miR-301a-3p. CONCLUSIONS: miR-301a-3p suppressed the posttranscriptional activity of ANKRD1, which is an activator of satellite cell proliferation, as determined with gain- and loss-of-function experiments. miR-301a-3p functions as an inducer of myogenesis by targeting the ANKRD1 gene in Muscovy ducks. These results provide novel insights into the early developmental process of black Muscovy breast muscles and will improve understanding of the underlying molecular mechanisms.


Asunto(s)
MicroARNs , Animales , MicroARNs/genética , MicroARNs/metabolismo , Patos/genética , Patos/metabolismo , Perfilación de la Expresión Génica , Músculo Esquelético/metabolismo , ARN Mensajero/genética , Transcriptoma
11.
Mol Microbiol ; 120(5): 740-753, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37804047

RESUMEN

The filamentous cyanobacterium Anabaena sp. PCC 7120 is able to form heterocysts for nitrogen fixation. Heterocyst differentiation is initiated by combined-nitrogen deprivation, followed by the commitment step during which the developmental process becomes irreversible. Mature heterocysts are terminally differentiated cells unable to divide, and cell division is required for heterocyst differentiation. Previously, we have shown that the HetF protease regulates cell division and heterocyst differentiation by cleaving PatU3, which is an inhibitor for both events. When hetF is required during the developmental program remains unknown. Here, by controlling the timing of hetF expression during heterocyst differentiation, we provide evidence that hetF is required just before the beginning of heterocyst morphogenesis. Consistent with this finding, transcriptome data show that most of the genes known to be involved in the early step (such as hetR and ntcA) or the commitment step (such as hetP and hetZ) of heterocyst development could be expressed in the ΔhetF mutant. In contrast, most of the genes involved in heterocyst morphogenesis and nitrogen fixation remain repressed in the mutant. These results indicated that in the absence of hetF, heterocyst differentiation is able to be initiated and proceeds to the stage just before heterocyst envelope formation.


Asunto(s)
Anabaena , Cianobacterias , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica/genética , Cianobacterias/metabolismo , Diferenciación Celular
12.
J Hum Genet ; 69(5): 197-203, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38374166

RESUMEN

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.


Asunto(s)
Proteína CapZ , Discapacidades del Desarrollo , Epilepsia , Heterocigoto , Hipotonía Muscular , Mutación , Preescolar , Femenino , Humanos , Masculino , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/patología , Epilepsia/genética , Secuenciación del Exoma , Discapacidad Intelectual/genética , Discapacidad Intelectual/patología , Hipotonía Muscular/genética , Hipotonía Muscular/patología , Fenotipo , Empalme del ARN/genética , Proteína CapZ/genética
13.
Inorg Chem ; 63(4): 1714-1719, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38231843

RESUMEN

Exploring nonlinear optical (NLO) materials with short ultraviolet cutoff edges are significant for developing an all-solid-state laser. Here, a noncentrosymmetric zinc fluoride hydrate, ZnF2(H2O)4, was synthesized by a hydrothermal method. It crystallizes in the polar space group of Pca21. The compound consists of the central Zn2+ combined with F- and coordination water to form the [ZnF2(H2O)4] octahedra, and each octahedron is isolated from each other to form a 0-dimensional structure. As an acentric compound, ZnF2(H2O)4 shows a phase-matchable second-harmonic-generation (SHG) activity with an intensity about 0.5 times that of KH2PO4. More attractively, it also shows a short ultraviolet cutoff edge below 200 nm, which is rare in reported halide hydrate systems. Interestingly, from ZnF2 to ZnF2(H2O)4, the partial substitution of the coordinated F atoms by H2O molecules leads to the structural transformation from centric to acentric with SHG activity off to on. Structural analyses, NLO activity, and theoretical calculations are presented in this work.

14.
Artículo en Inglés | MEDLINE | ID: mdl-38595104

RESUMEN

OBJECTIVE: The purpose of this study is to identify the presence of occult peritoneal metastasis (OPM) in patients with advanced gastric cancer (AGC) by using clinical characteristics and abdominopelvic computed tomography (CT) features. METHODS: This retrospective study included 66 patients with OPM and 111 patients without peritoneal metastasis (non-PM [NPM]) who underwent preoperative contrast-enhanced CT between January 2020 and December 2021. Occult PMs means PMs that are missed by CT but later diagnosed by laparoscopy or laparotomy. Patients with NPM means patients have neither PM nor other distant metastases, indicating there is no evidence of distant metastases in patients with AGC. Patients' clinical characteristics and CT features such as tumor marker, Borrmann IV, enhancement patterns, and pelvic ascites were observed by 2 experienced radiologists. Computed tomography features and clinical characteristics were combined to construct an indicator for identifying the presence of OPM in patients with AGC based on a logistic regression model. Receiver operating characteristic curves and the area under the receiver operating characteristic curve (AUC) were generated to assess the diagnostic performance of the combined indicator. RESULTS: Four independent predictors (Borrmann IV, pelvic ascites, carbohydrate antigen 125, and normalized arterial CT value) differed significantly between OPM and NPM and performed outstandingly in distinguishing patients with OPM from those without PM (AUC = 0.643-0.696). The combined indicator showed a higher AUC value than the independent risk factors (0.820 vs 0.643-0.696). CONCLUSIONS: The combined indicator based on abdominopelvic CT features and carbohydrate antigen 125 may assist clinicians in identifying the presence of CT OPMs in patients with AGC.

15.
BMC Geriatr ; 24(1): 429, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750429

RESUMEN

BACKGROUND: The objective of this research is to investigate the dynamic developmental trends between Age-Friendly Environments (AFE) and healthy aging in the Chinese population. METHODS: This study focused on a sample of 11,770 participants from the CHARLS and utilized the ATHLOS Healthy Aging Index to assess the level of healthy aging among the Chinese population. Linear mixed model (LMM) was used to explore the relationship between AFE and healthy aging. Furthermore, a cross-lagged panel model (CLPM) and a random-intercept cross-lagged panel model (RI-CLPM) were used to examine the dynamic developmental trends of healthy aging, taking into account both Between-Person effects and Within-Person effects. RESULTS: The results from LMM showed a positive correlation between AFE and healthy aging (ß = 0.087, p < 0.001). There was a positive interaction between the geographic distribution and AFE (central region * AFE: ß = 0.031, p = 0.038; eastern region * AFE: ß = 0.048, p = 0.003). In CLPM and RI-CLPM, the positive effect of healthy aging on AFE is a type of Between-Person effects (ß ranges from 0.147 to 0.159, p < 0.001), while the positive effect of AFE on healthy aging is Within-Person effects (ß ranges from 0.021 to 0.024, p = 0.004). CONCLUSION: Firstly, individuals with high levels of healthy aging are more inclined to actively participate in the development of appropriate AFE compared to those with low levels of healthy aging. Furthermore, by encouraging and guiding individuals to engage in activities that contribute to building appropriate AFE, can elevate their AFE levels beyond the previous average level, thereby improving their future healthy aging levels. Lastly, addressing vulnerable groups by reducing disparities and meeting their health needs effectively is crucial for fostering healthy aging in these populations.


Asunto(s)
Envejecimiento Saludable , Humanos , Envejecimiento Saludable/fisiología , China/epidemiología , Estudios Longitudinales , Masculino , Femenino , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Jubilación/tendencias , Pueblos del Este de Asia
16.
Proc Natl Acad Sci U S A ; 118(35)2021 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-34446551

RESUMEN

Many G protein-coupled receptors and other signaling proteins localize to the ciliary membrane for regulating diverse cellular processes. The BBSome composed of multiple Bardet-Biedl syndrome (BBS) proteins is an intraflagellar transport (IFT) cargo adaptor essential for sorting signaling proteins in and/or out of cilia via IFT. Leucine zipper transcription factor-like 1 (LZTFL1) protein mediates ciliary signaling by controlling BBSome ciliary content, reflecting how LZTFL1 mutations could cause BBS. However, the mechanistic mechanism underlying this process remains elusive thus far. Here, we show that LZTFL1 maintains BBSome ciliary dynamics by finely controlling BBSome recruitment to the basal body and its reassembly at the ciliary tip simultaneously in Chlamydomonas reinhardtii LZTFL1 directs BBSome recruitment to the basal body via promoting basal body targeting of Arf-like 6 GTPase BBS3, thus deciding the BBSome amount available for loading onto anterograde IFT trains for entering cilia. Meanwhile, LZTFL1 stabilizes the IFT25/27 component of the IFT-B1 subcomplex in the cell body so as to control its presence and amount at the basal body for entering cilia. Since IFT25/27 promotes BBSome reassembly at the ciliary tip for loading onto retrograde IFT trains, LZTFL1 thus also directs BBSome removal out of cilia. Therefore, LZTFL1 dysfunction deprives the BBSome of ciliary presence and generates Chlamydomonas cells defective in phototaxis. In summary, our data propose that LZTFL1 maintains BBSome dynamics in cilia by such a dual-mode system, providing insights into how LZTFL1 mediates ciliary signaling through maintaining BBSome ciliary dynamics and the pathogenetic mechanism of the BBS disorder as well.


Asunto(s)
Chlamydomonas reinhardtii/fisiología , Cilios/fisiología , Fototaxis , Factores de Transcripción/fisiología , Síndrome de Bardet-Biedl , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Unión Proteica , Transducción de Señal
17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(3): 257-265, 2024 Mar 10.
Artículo en Zh | MEDLINE | ID: mdl-38448011

RESUMEN

OBJECTIVE: To assess the value of optical genome mapping (OGM) for the detection of chromosomal structural abnormalities including ring chromosomes, balanced translocations, and insertional translocations. METHODS: Clinical data of four patients who underwent pre-implantation genetic testing concurrently with OGM and chromosomal microarray analysis at the Center of Reproductive Medicine of the Sixth Affiliated Hospital of Sun Yat-sen University from January to October 2022 due to chromosomal structural abnormalities were selected as the study subjects. Some of the results were verified by multi-color fluorescence in situ hybridization. RESULTS: The OGM has successfully detected a balanced translocation and fine mapped the breakpoints in a patient. Among two patients with insertional translocations, OGM has provided more refined breakpoint locations than karyotyping analysis in a patient who had chromosome 3 inserted into chromosome 6 and determined the direction of the inserted fragment. However, OGM has failed to detect the chromosomal abnormality in a patient with chromosome 8 inserted into the Y chromosome. It has also failed to detect circular signals in a patient with ring chromosome mosaicism. CONCLUSION: OGM has successfully detected chromosomal structural variations in the four patients and provided assistance for their diagnosis.


Asunto(s)
Cromosomas Humanos Par 3 , Cromosomas en Anillo , Humanos , Hibridación Fluorescente in Situ , Cromosomas Humanos Par 6 , Translocación Genética , Mapeo Cromosómico
18.
J Intern Med ; 293(3): 371-383, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36382924

RESUMEN

BACKGROUND: Low-dose aspirin and metformin have been individually associated with a reduced risk of cancer. Whether their concurrent use in adults with type 2 diabetes mellitus (T2DM) is associated with a reduced risk of colorectal cancer (CRC) is unclear. OBJECTIVE: Among individuals with T2DM taking metformin, we sought to evaluate the association between low-dose aspirin versus no aspirin and the risk of CRC. METHODS: A multiple-database new-user cohort study of patients with T2DM taking metformin was conducted between 2007 and 2010 (Clinical Data Analysis and Reporting System [CDARS], Hong Kong) and 2007-2016 (The Health Improvement Network [THIN], UK). The primary outcome was incident CRC. Patients were followed from index date of prescription until the earliest occurrence of an outcome of interest, an incident diagnosis of any cancer, death, or until 31 December 2019. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CI). Estimates were pooled using an inverse variance random effects model, and heterogeneity was assessed using I2 . RESULTS: After one-to-one propensity-score matching, 57,534 patients were included (CDARS = 16,276; THIN = 41,258). The median (IQR) follow-up was 9.3 (6.5-10.7) years in CDARS and 3.2 (1.1-5.8) years in THIN. The concurrent use of low-dose aspirin and metformin was not associated with a lower risk of CRC compared to metformin only (HR = 0.89, 95% CI 0.75-1.05, I2  = 0%). CONCLUSION: Low-dose aspirin was not associated with a lower risk of CRC in patients with T2DM taking metformin. Our study does not support the routine use of low-dose aspirin in this population.


Asunto(s)
Neoplasias Colorrectales , Diabetes Mellitus Tipo 2 , Metformina , Adulto , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Metformina/uso terapéutico , Hipoglucemiantes/uso terapéutico , Estudios de Cohortes , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/prevención & control , Aspirina/uso terapéutico
19.
Small ; 19(35): e2301519, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37156740

RESUMEN

Combination therapies involving metabolic regulation and immune checkpoint blockade are considered an encouraging new strategy for cancer therapy. However, the effective utilization of combination therapies for activating tumor-associated macrophages (TAMs) remains challenging. Herein, a lactate-catalyzed chemodynamic approach to activate the therapeutic genome editing of signal-regulatory protein α (SIRPα) to reprogram TAMs and improve cancer immunotherapy is proposed. This system is constructed by encapsulating lactate oxidase (LOx) and clustered regularly interspaced short palindromic repeat-mediated SIRPα genome-editing plasmids in a metal-organic framework (MOF). The genome-editing system is released and activated by acidic pyruvate, which is produced by the LOx-catalyzed oxidation of lactate. The synergy between lactate exhaustion and SIRPα signal blockade can enhance the phagocytic ability of TAMs and promote the repolarization of TAMs to the antitumorigenic M1 phenotype. Lactate exhaustion-induced CD47-SIRPα blockade efficiently improves macrophage antitumor immune responses and effectively reverses the immunosuppressive tumor microenvironment to inhibit tumor growth, as demonstrated by in vitro and in vivo studies. This study provides a facile strategy for engineering TAMs in situ by combining CRISPR-mediated SIRPα knockout with lactate exhaustion for effective immunotherapy.


Asunto(s)
Edición Génica , Neoplasias , Humanos , Ácido Láctico/metabolismo , Macrófagos/metabolismo , Neoplasias/tratamiento farmacológico , Inmunoterapia , Microambiente Tumoral
20.
Small ; : e2308348, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38050941

RESUMEN

Perovskite structure compounds are significant candidates for designing new optical function materials due to their structural variability. Here, an inorganic tetravalent cerium fluoride, Na2 CeF6 , is derived from the perovskite structure through double-site cation co-substitution. Na2 CeF6 crystalizes in the non-centrosymmetric space group P 6 ¯ 2 m ${P}^{\bar{6}}2m$ . Edge-sharing connected NaF9 and CeF9 polyhedra build the whole 3D structure of Na2 CeF6 . Importantly, it represents the first Ce(IV) fluoride nonlinear optical (NLO) crystal and can produce a strong and phase-matchable second-harmonic generation (SHG) effect of ≈2.1 times that of KH2 PO4 (KDP), making it the strongest among non-lone pair electron metal fluoride system. Further, it exhibits a high laser-induced damage threshold (LIDT) of 74.65-76.25 MW cm-2 , which is over 20 times that of AgGaS2 . It also exhibits a wide transparent region (0.5-14.3 µm). This work provides a facile route for exploring high-performance halide NLO materials.

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