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1.
ACS Nano ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38700899

RESUMEN

Spin in semiconductors facilitates magnetically controlled optoelectronic and spintronic devices. In metal halide perovskites (MHPs), doping magnetic ions is proven to be a simple and efficient approach to introducing a spin magnetic momentum. In this work, we present a facile metal ion doping protocol through the vapor-phase metal halide insertion reaction to the chemical vapor deposition (CVD)-grown ultrathin Cs3BiBr6 perovskites. The Fe-doped bismuth halide (Fe:CBBr) perovskites demonstrate that the iron spins are successfully incorporated into the lattice, as revealed by the spin-phonon coupling below the critical temperature Tc around 50 K observed through temperature-dependent Raman spectroscopy. Furthermore, the phonons exhibit significant softening under an applied magnetic field, possibly originating from magnetostriction and spin exchange interaction. The spin-phonon coupling in Fe:CBBr potentially provides an efficient way to tune the spin and lattice parameters for halide perovskite-based spintronics.

2.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(2): 232-236, 2024 Mar 30.
Artículo en Chino | MEDLINE | ID: mdl-38605628

RESUMEN

In order to realize the diagnosis of slit lamp in cross-regional patients and improve the real-time and convenience of diagnosis, a remote slit lamp diagnosis platform based on Internet of Things (IoT) technology is designed. Firstly, the feasibility of remote slit lamp is analyzed. Secondly, the IoT platform architecture of doctor/server/facility (D/S/F) is proposed and a remote slit lamp is designed. Finally, the performance of the remote slit lamp diagnostic platform is tested. The platform solves the communication problem of distributed slit lamps and realizes respectively numerical control of multi-area slit lamp by multi-eye experts. The test results show that the remote control delay of the platform is less than 20 ms, which supports multiple experts to diagnose multiple patients separately.


Asunto(s)
Internet de las Cosas , Lámpara de Hendidura , Humanos , Tecnología
3.
Front Cell Dev Biol ; 12: 1381920, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38566827

RESUMEN

Introduction: Despite the abundance of research indicating the participation of immune cells in prostate cancer development, establishing a definitive cause-and-effect relationship has proven to be a difficult undertaking. Methods: This study employs Mendelian randomization (MR), leveraging genetic variables related to immune cells from publicly available genome-wide association studies (GWAS), to investigate this association. The primary analytical method used in this study is inverse variance weighting (IVW) analysis. Comprehensive sensitivity analyses were conducted to assess the heterogeneity and horizontal pleiotropy of the results. Results: The study identifies four immune cell traits as causally contributing to prostate cancer risk, including CD127- CD8+ T cell %CD8+ T cell (OR = 1.0042, 95%CI:1.0011-1.0073, p = 0.0077), CD45RA on CD39+ resting CD4 regulatory T cell (OR = 1.0029, 95%CI:1.0008-1.0050, p = 0.0065), CD62L- Dendritic Cell Absolute Count (OR = 1.0016; 95%CI:1.0005-1.0026; p = 0.0039), CX3CR1 on CD14+ CD16- monocyte (OR = 1.0024, 95%CI:1.0007-1.0040, p = 0.0060). Additionally, two immune cell traits are identified as causally protective factors: CD4 on monocyte (OR = 0.9975, 95%CI:0.9958-0.9992, p = 0.0047), FSC-A on plasmacytoid Dendritic Cell (OR = 0.9983, 95%CI:0.9970-0.9995, p = 0.0070). Sensitivity analyses indicated no horizontal pleiotropy. Discussion: Our MR study provide evidence for a causal relationship between immune cells and prostate cancer, holding implications for clinical diagnosis and treatment.

4.
Adv Mater ; 36(13): e2312081, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38102981

RESUMEN

Osteoporosis, characterized by an imbalance in bone homeostasis, is a global health concern. Bone defects are difficult to heal in patients with osteoporosis. Classical drug treatments for osteoporotic bone defects have unsatisfactory efficacy owing to side effects and imprecise delivery problems. In this study, a magnetic aggregation-induced bone-targeting poly(lactic-co-glycolic acid, PLGA)-based nanocarrier (ZOL-PLGA@Yoda1/SPIO) is synthesized to realize dual-targeted delivery and precise Piezo1-activated therapy for osteoporotic bone defects. Piezo1 is an important mechanotransducer that plays a key role in regulating bone homeostasis. To achieve dual-targeting properties, ZOL-PLGA@Yoda1/SPIO is fabricated using zoledronate (ZOL)-decorated PLGA, superparamagnetic iron oxide (SPIO), and Piezo1-activated molecule Yoda1 via the emulsion solvent diffusion method. Bone-targeting molecular mediation and magnetic aggregation-induced properties can jointly and effectively achieve precise delivery to localized bone defects. Moreover, Yoda1 loading enables targeted and efficient mimicking of mechanical signals and activation of Piezo1. Experiments in vivo and in vitro demonstrate that ZOL-PLGA@Yoda1/SPIO can activate Piezo1 in bone defect areas of osteoporotic mice, improve osteogenesis through YAP/ß-catenin signaling axis, promote a well-coordinated osteogenesis-angiogenesis coupling, and significantly accelerate bone reconstruction within the defects without noticeable side effects. Overall, this novel dual-targeting nanocarrier provides a potentially effective strategy for the clinical treatment of osteoporotic bone defects.


Asunto(s)
Compuestos Férricos , Osteogénesis , Osteoporosis , Humanos , Ratones , Animales , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Osteoporosis/tratamiento farmacológico , Fenómenos Magnéticos , Canales Iónicos
5.
Org Lett ; 25(42): 7716-7720, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37842950

RESUMEN

Herein, a direct cross-dehydrogenative C-H amination of indoles has been successfully achieved, enabled by the merger of photocatalysis with nickel catalysis. This developed process does not require stoichiometric oxidants and prefunctionalization of amine partners, providing a concise platform for C-N bond formation. Moreover, the synthetic practicality of this transformation was well revealed by its high step- and atom-economy, high reaction efficiency, and broad functional group tolerance.

6.
Org Lett ; 25(38): 7062-7066, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37726866

RESUMEN

A visible-light-induced radical relay strategy to access heterocycles bearing a monofluoromethylsufonyl moiety is reported, with PhI(OCOCH2F)2 as the CH2F radical precursor and DABSO as the SO2 source. A range of oxindoles, containing a CH2FSO2CH2- group at the C3 position, were synthesized from N-arylacrylamides in up to 97% yields. The protocol features catalyst-free photochemical tandem, mild reaction conditions, broad functional group compatibility, and good to excellent yields.

7.
Redox Biol ; 62: 102677, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36989572

RESUMEN

Ferroptosis, an iron-dependent lipid peroxidation-driven programmed cell death, is closely related to cancer therapy. The development of druggable ferroptosis inducers and their rational application in cancer therapy are critical. Here, we identified Tubastatin A, an HDAC6 inhibitor as a novel druggable ferroptosis inducer through large-scale drug screening. Tubastatin A directly bonded to GPX4 and inhibited GPX4 enzymatic activity through biotin-linked Tubastatin A putdown and LC/MS analysis, which is independent of its inhibition of HDAC6. In addition, our results showed that radiotherapy not only activated Nrf2-mediated GPX4 transcription but also inhibited lysosome-mediated GPX4 degradation, subsequently inducing ferroptosis tolerance and radioresistance in cancer cells. Tubastatin A overcame ferroptosis resistance and radioresistance of cancer cells by inhibiting GPX4 enzymatic activity. More importantly, Tubastatin A has excellent bioavailability, as demonstrated by its ability to significantly promote radiotherapy-induced lipid peroxidation and tumour suppression in a mouse xenograft model. Our findings identify a novel druggable ferroptosis inducer, Tubastatin A, which enhances radiotherapy-mediated antitumor effects. This work provides a compelling rationale for the clinical evaluation of Tubastatin A, especially in combination with radiotherapy.


Asunto(s)
Ferroptosis , Neoplasias , Humanos , Animales , Ratones , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Apoptosis , Peroxidación de Lípido
8.
Nano Lett ; 23(5): 2023-2030, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36797055

RESUMEN

Topological phonons and magnons potentially enable low-loss, quantum coherent, and chiral transport of information and energy at the atomic scale. Van der Waals magnetic materials are promising to realize such states due to their recently discovered strong interactions among the electronic, spin, and lattice degrees of freedom. Here, we report the first observation of coherent hybridization of magnons and phonons in monolayer antiferromagnet FePSe3 by cavity-enhanced magneto-Raman spectroscopy. The robust magnon-phonon cooperativity in the 2D limit occurs even in zero magnetic field, which enables nontrivial band inversion between longitudinal and transverse optical phonons caused by the strong coupling with magnons. The spin and lattice symmetry theoretically guarantee magnetic-field-controlled topological phase transition, verified by nonzero Chern numbers calculated from the coupled spin-lattice model. The 2D topological magnon-phonon hybridization potentially offers a new route toward quantum phononics and magnonics with an ultrasmall footprint.

9.
J Orthop Surg Res ; 18(1): 47, 2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36647099

RESUMEN

BACKGROUND: This study investigated the characteristics of humeral geometric and morphological parameters in northern Chinese population by three-dimensional measurements, and compared whether there were differences in humeral morphology among populations from different geographical regions. METHODS: Computed tomography scans of 80 humerus were obtained, reconstructed and measured. Differences in humeral morphological parameters between genders and sides were compared. Correlation analysis was used to explore possible correlations among the parameters. The differences in humeral geometric morphometric parameters between Western and East Asian populations were compared according to pool results of present and previous studies. RESULTS: The average (and standard deviation) of humeral head radius curvature, arc angle, diameter, and thickness was 151.79 ± 6.69°, 23.36 ± 2.08 mm, 44.83 ± 3.92 mm and 17.55 ± 1.84 mm in coronal humeral head plane, and 152.05 ± 8.82°, 21.81 ± 1.88 mm, 41.77 ± 3.44 mm and 16.52 ± 1.92 mm in transversal humeral head plane. The average of the humeral head medial offset and posterior offset was 7.34 ± 2.47 mm and 0.08 ± 1.72 mm. Humeral head inclination angle, arc angle and radius curvature of humeral neck-shaft averaged 137.69 ± 4.92°, 34.7 ± 5.29° and 55.76 ± 13.43 mm. Superior, inferior, anterior, posterior concave angle of humeral anatomical neck averaged 150.41 ± 10.91°, 146.55 ± 10.12°, 146.43 ± 13.53° and 149.33 ± 14.07°. The average of height of the greater tuberosity, height of the lesser tuberosity, depth, concave angle and volume of the intertubercular groove was 14.19 ± 1.7 mm, 8.9 ± 1.54 mm, 0.92 ± 0.31 mm3, 31.28 ± 9.61 mm, 4.98 ± 1.19 mm and 89.35 ± 17.62°. The upper angle of the greater tuberosity averaged 161.04 ± 7.84°, the upper angle of the greater tuberosity was 165.94 ± 3.6°. Differences in parameters of proximal humerus between genders and sides were found. There was no correlation between parameters of proximal humerus and age. Correlations were found among humeral morphological parameters. East Asian populations differed in proximal humeral morphology from Western populations. CONCLUSIONS: This study will provide references for diagnosing and classifying shoulder disease, designing prosthesis and instrument, enhancing surgical precision and guiding patient recovery.


Asunto(s)
Artroplastia de Reemplazo , Articulación del Hombro , Femenino , Humanos , Masculino , Artroplastia de Reemplazo/métodos , Pueblos del Este de Asia , Cabeza Humeral/diagnóstico por imagen , Cabeza Humeral/cirugía , Húmero/diagnóstico por imagen , Húmero/cirugía , Hombro/cirugía , Articulación del Hombro/cirugía , Tomografía Computarizada por Rayos X , China
10.
J Org Chem ; 88(10): 6354-6363, 2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35723452

RESUMEN

A visible-light-induced defluorinative dichloromethylation of α-CF3 alkenes was developed with cheap and readily accessible chloroform simultaneously as a dichloromethylation reagent and reaction medium, leading to the facile preparation of new polyhalogenated scaffolds. Notably, the change from CHCl3 to CDCl3 offers a straightforward pathway for accessing the deuterated analogues with excellent degrees of D incorporation. Mechanistic studies suggested the reaction underwent a radical addition of the dichloromethyl radical with alkenes, followed by sequential single-electron transfer and defluorination. This protocol features mild conditions, easy operation, facile scalability, and high efficiency, allowing convenient access to dichloronated gem-difluoroalkenes.

11.
Front Surg ; 9: 1035840, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36439530

RESUMEN

Background: Damage to the parathyroid glands remains a frequent complication after thyroidectomy, often resulting in hypoparathyroidism. Accordingly, identifying the parathyroid glands during thyroid surgical procedures is indispensable to prevent accidental surgical removal. Methods: The participants were randomly divided into three groups (indocyanine green [ICG], nanocarbon [NC], and control group). To identify and protect parathyroid glands during neck lymph node dissection in patients with thyroid cancer, IG was intravenously administered to the ICG group, whereas the NC group received an intra-thyroid injection of the NC suspension before dissection. IG was intravenously administered to each group after dissection. Subsequently, we analyzed surgical outcomes, including operative time, number of lymph nodes, serum calcium, and number of parathyroid glands. Results: We included 30 patients who underwent gasless transaxillary endoscopic thyroidectomy for thyroid cancer. Based on our findings, a greater number of parathyroid glands (P < 0.01) and higher postoperative parathyroid hormone (PTH) levels were detected in the NC and ICG groups than those in the control group (P < 0.01). The number of parathyroid glands and postoperative PTH levels in the NC group were higher than those in the ICG group (P < 0.01). Conclusions: Gasless transaxillary endoscopic thyroidectomy with NC and ICG for thyroid cancer could effectively protect the parathyroid gland and afford satisfactory clinical efficacy. NC could offer an advantage over ICG for protecting the parathyroid gland.

12.
Angew Chem Int Ed Engl ; 61(44): e202212292, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36083417

RESUMEN

A metal-free photosensitized protocol for regioselective diamination of alkene feedstocks over a single step was developed based on the rationally designed bifunctional diamination reagent, thus affording a range of differentially protected 1,2-diamines in moderate to high yields. Mechanistic studies reveal that the reaction is initiated with a triplet-triplet energy transfer between thioxanthone catalyst and diamination reagent, followed by fragmentation to simultaneously generate long-lived iminyl radical and transient amidyl radical. The excellent regioselectivity presumably stems from the large reactivity difference between two different N-centered radical species. This protocol is characterized by excellent regioselectivity, broad functional group tolerance, and mild reaction conditions, which would enrich the diversity and versatility of facilitate the diversity-oriented synthesis of 1,2-diamine-containing complex molecule scaffolds.

13.
Angew Chem Int Ed Engl ; 61(45): e202211035, 2022 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-36111983

RESUMEN

An unprecedented photoredox-catalyzed phosphine-mediated deoxygenation of hexafluoroacetone hydrate was established to accomplish the hydroxylpolyfluoroalkylation of electron-deficient alkenes. A range of bis(trifluoromethyl)carbinols were facilely accessed by using readily available hexafluoroacetone hydrate, instead of toxic gaseous hexafluoroacetone. A range of electron-deficient alkenes are tolerated, giving the corresponding hydro-hydroxylpolyfluoroalkylated products in moderate to high yields. Remarkable features of this synthetic strategy include operational simplicity, mild reaction conditions, excellent regioselectivity, and broad functional group tolerance. The success of this strategy relies on the delicate utilization of aldehyde/ketone-gem-diol intrinsic equilibrium, which offers an innovated open-shell pathway for the assembly of synthetically challenging polyfluoroalkylated scaffolds.


Asunto(s)
Alquenos , Fluorocarburos , Catálisis , Acetona
14.
Org Lett ; 24(25): 4640-4644, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35729079

RESUMEN

A photoinduced, photocatalyst-free cyanoalkylation of nitrostyenes was explored, affording a series of cyanoalkylated alkenes in moderate to good yields. Mechanistic studies reveal that an electron donor-acceptor complex formed between O-aryl oximes and DIPEA is presumably involved in this process. The excellent functional group compatibility of this newly designed synthetic protocol allows for cyanoalkylation of structurally varied substrates, which offers an eco-friendly pathway for the assembly of cyanoalkylated alkenes.

15.
Int Orthop ; 46(8): 1811-1819, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35668240

RESUMEN

PURPOSE: The purpose of our study is to compare the anatomic parameters of proximal humerus, glenoid, and glenohumeral joint between patients with recurrent anterior shoulder dislocation (RASD) and patients without RASD with the assistance of three-dimensional (3D) CT scans. METHODS: Sixty patients were included in the study and divided into group RASD and group control. 3D-CT models of shoulder joint for each included patient were reconstructed and multiple anatomic parameters were measured. RESULTS: There were no statistically significant differences between the two groups in morphological parameters of humerus and glenohumeral joints. Long diameter of glenoid was 3.50 ± 0.34 cm for patients in group RASD and 3.31 ± 0.32 cm in group control (p = 0.039). There was a statistically significant difference in the ratio of long to short diameter of glenoid (p < 0.001). Ratio of humeral head height to glenoid long diameter (Hhh/Gld) was 1.02 ± 0.07 in group RASD, significantly lower than 1.09 ± 0.08 in group control (p = 0.001). Longitudinal depth of glenoid was significantly higher in group RASD (p = 0.013). CONCLUSION: The glenoid morphology along long diameter is closely correlated with the stability of glenohumeral joint, including glenoid long diameter and glenoid longitudinal depth. It is especially noteworthy that the value of Hhh/Gld decreases in patients with RASD. The difference of Hhh/Gld between the two groups reminds us that the correlation of bony structure along long diameter between glenoid and humeral head plays an important role in RASD.


Asunto(s)
Cavidad Glenoidea , Luxaciones Articulares , Inestabilidad de la Articulación , Luxación del Hombro , Articulación del Hombro , Estudios de Casos y Controles , Cavidad Glenoidea/diagnóstico por imagen , Humanos , Cabeza Humeral/diagnóstico por imagen , Hombro , Luxación del Hombro/diagnóstico por imagen , Articulación del Hombro/anatomía & histología , Articulación del Hombro/diagnóstico por imagen , Tomografía Computarizada por Rayos X
16.
Nat Commun ; 13(1): 2527, 2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35534477

RESUMEN

Electron band topology is combined with intrinsic magnetic orders in MnBi2Te4, leading to novel quantum phases. Here we investigate collective spin excitations (i.e. magnons) and spin fluctuations in atomically thin MnBi2Te4 flakes using Raman spectroscopy. In a two-septuple layer with non-trivial topology, magnon characteristics evolve as an external magnetic field tunes the ground state through three ordered phases: antiferromagnet, canted antiferromagnet, and ferromagnet. The Raman selection rules are determined by both the crystal symmetry and magnetic order while the magnon energy is determined by different interaction terms. Using non-interacting spin-wave theory, we extract the spin-wave gap at zero magnetic field, an anisotropy energy, and interlayer exchange in bilayers. We also find magnetic fluctuations increase with reduced thickness, which may contribute to a less robust magnetic order in single layers.

17.
Org Biomol Chem ; 20(21): 4415-4420, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35583213

RESUMEN

The mechanism of the phosphine-catalysed domino sequence of alkynoates and activated methylenes has been computationally studied. The computational results revealed that the [3 + 2] annulation sequence could be ruled out, due to a difficult Knoevenagel condensation of aromatic aldehydes and active methylenes. The reaction proceeds through a [4 + 1] annulation pathway, which involves a phosphine-catalysed MBH-type reaction followed by a [1,5]-proton shift and dehydration to afford vinyl phosphonium intermediates as four-carbon synthons in the annulation reaction. Then 1,3-dicarbonyls act as nucleophiles to attack vinyl phosphonium intermediates, subsequently leading to a stepwise [1,3]-proton shift and an intramolecular nucleophilic attack to close the five-member ring.

18.
J Org Chem ; 87(7): 4732-4741, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35317557

RESUMEN

Reported herein is a visible-light-induced, catalyst-free intramolecular cyclization of 4-phenylsulfonyl-2,3,5,6-tetrachloropyridine, leading to rapid assembly of a series of unprecedented benzo[4,5]thieno[3,2-c]pyridine 5,5-dioxide scaffolds under mild conditions. The rational introduction of a perchloropyridin-4-yl module significantly facilitated this photoinduced process and offers a versatile platform for broad structural variation. Mechanistic studies revealed that a newly identified charge-transfer complex with carbonate is crucial to this photoinduced process.

19.
Nat Cell Biol ; 24(1): 88-98, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35027735

RESUMEN

The accumulation of lipid peroxides is recognized as a determinant of the occurrence of ferroptosis. However, the sensors and amplifying process of lipid peroxidation linked to ferroptosis remain obscure. Here we identify PKCßII as a critical contributor of ferroptosis through independent genome-wide CRISPR-Cas9 and kinase inhibitor library screening. Our results show that PKCßII senses the initial lipid peroxides and amplifies lipid peroxidation linked to ferroptosis through phosphorylation and activation of ACSL4. Lipidomics analysis shows that activated ACSL4 catalyses polyunsaturated fatty acid-containing lipid biosynthesis and promotes the accumulation of lipid peroxidation products, leading to ferroptosis. Attenuation of the PKCßII-ACSL4 pathway effectively blocks ferroptosis in vitro and impairs ferroptosis-associated cancer immunotherapy in vivo. Our results identify PKCßII as a sensor of lipid peroxidation, and the lipid peroxidation-PKCßII-ACSL4 positive-feedback axis may provide potential targets for ferroptosis-associated disease treatment.


Asunto(s)
Coenzima A Ligasas/metabolismo , Ferroptosis/fisiología , Peroxidación de Lípido/fisiología , Proteína Quinasa C beta/metabolismo , Animales , Sistemas CRISPR-Cas/genética , Línea Celular Tumoral , Técnicas de Inactivación de Genes , Humanos , Inmunoterapia/métodos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Neoplasias/terapia , Fosforilación , Proteína Quinasa C beta/genética
20.
Org Lett ; 24(3): 924-928, 2022 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-35040648

RESUMEN

A highly modular 1,4-difunctionalization of 1,3-dienes with bromodifluoroacetamides and sulfinates/amines through a photoinduced palladium-catalyzed radical relay process is described herein. This developed protocol offers a facile and general route to access a variety of value-added CF2-incorporated alkenes in moderate to good yields. The versatility and flexibility of this approach have been well illustrated by readily accessible starting materials, synthetic convenience, and wide functional group compatibility.

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