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1.
Nat Chem Biol ; 20(4): 484-492, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37945893

RESUMO

GPR101 is an orphan G protein-coupled receptor actively participating in energy homeostasis. Here we report the cryo-electron microscopy structure of GPR101 constitutively coupled to Gs heterotrimer, which reveals unique features of GPR101, including the interaction of extracellular loop 2 within the 7TM bundle, a hydrophobic chain packing-mediated activation mechanism and the structural basis of disease-related mutants. Importantly, a side pocket is identified in GPR101 that facilitates in silico screening to identify four small-molecule agonists, including AA-14. The structure of AA-14-GPR101-Gs provides direct evidence of the AA-14 binding at the side pocket. Functionally, AA-14 partially restores the functions of GH/IGF-1 axis and exhibits several rejuvenating effects in wild-type mice, which are abrogated in Gpr101-deficient mice. In summary, we provide a structural basis for the constitutive activity of GPR101. The structure-facilitated identification of GPR101 agonists and functional analysis suggest that targeting this orphan receptor has rejuvenating potential.


Assuntos
Receptores Acoplados a Proteínas G , Camundongos , Animais , Microscopia Crioeletrônica , Receptores Acoplados a Proteínas G/metabolismo , Ligantes
2.
Appl Opt ; 62(14): 3519-3527, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37706964

RESUMO

A switchable and tunable dual-function absorber/polarization converter is presented in this work. The constitution of the structure, which incorporates patterned graphene and photosensitive silicon (Si), can minimize undesired optical losses. Simulated results show that when the Si is metallic, the structure behaves as a broadband absorption of more than 90% in the range of 1.45-3.36 THz. Its peak absorption can be tuned from 22% to 99.8% by changing the Fermi energy of graphene. Furthermore, the interference theory analyzes the physical mechanism for broadband absorption. When the Si is in the dielectric state, the structure has a transmission polarization conversion function, which realizes the conversion from linear to cross-polarized waves. The polarization conversion ratio (PCR) is greater than 90% in the 3.82-4.43 THz range. Meanwhile, the cross-polarization transmission can be dynamically tuned from 28% to 97%, and the PCR can also be tuned from 17% to 99.9% by adjusting the conductivity of the Si. The reason for realizing polarization conversion is explained by the polarization decomposition method. This study provides a design opinion of high-performance multifunctional tunable terahertz devices.

3.
Sensors (Basel) ; 23(9)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37177677

RESUMO

In this study, the integrated three-in-one (temperature, humidity, and wind speed) microsensor was made through the technology of the Micro-electro-mechanical Systems (MEMS) to measure three important physical quantities of the internal environment of the cold air pipe of the Heating, Ventilation and Air Conditioning (HVAC) in the factory, plan the installation positions of the integrated three-in-one microsensor and commercially available wind speed sensor required by the internal environment of the cold air pipe, and conduct the actual 310-h long term test and comparison. In the experiment, it was also observed that the self-made micro wind speed sensor had higher stability compared to the commercially available wind speed sensor (FS7.0.1L.195). The self-made micro wind speed sensor has a variation range of ±200 mm/s, while the commercially available wind speed sensor a variation range of ±1000 mm/s. The commercially available wind speed sensor (FS7.0.1L.195) can only measure the wind speed; however, the self-made integrated three-in-one microsensor can conduct real-time measurements of temperature and humidity according to the environment at that time, and use different calibration curves to know the wind speed. As a result, it is more accurate and less costly than commercially available wind speed sensors. The material cost of self-made integrated three-in-one microsensor includes chemicals, equipment usage fees, and wires. In the future, factories may install a large number of self-made integrated three-in-one microsensors in place of commercially available wind speed sensors. Through real-time wireless measurements, the self-made integrated three-in-one microsensors can achieve the control optimization of the HVAC cold air pipe's internal environment to improve the quality of manufactured materials.

4.
BMC Oral Health ; 23(1): 508, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37479973

RESUMO

BACKGROUND: Whether slim the face or not after removed third molars is the concern of some orthodontic treatment candidates. The aim of this article is to explore the volume changes of facial soft and hard tissues after third molars extraction, as well as develop a reproducible clinical protocol to precisely assess facial soft tissue volume change. METHODS: A non-randomized, non-blind, self-controlled pilot study was conducted. 24 adults aged 18-30 had ipsilateral third molars extracted. The body weight change was controlled within 2 kg. Structured light scans were taken under a standardized procedure pre-extraction (T0), three (T1), and six (T2) months post-extraction; CBCTs were taken at T0 and T2. The projection method was proposed to measure the soft tissue volume (STV) and the soft tissue volume change (STVC) by the Geomagic software. The hard tissue volume change (HTVC) was measured in the Dragonfly software. RESULTS: The final sample size is 23, including 5 males (age 26.6 ± 2.5 years) and 18 females (age 27.3 ± 2.5 years). The HTVC was - 2.33 ± 0.46ml on the extraction side. On the extraction side, the STV decreased by 1.396 (95% CI: 0.323-2.470) ml (P < 0.05) at T1, and increased by 1.753 (95% CI: -0.01-3.507) ml (P = 0.05) at T2. T2 and T0 had no difference (P > 0.05). The inter and intra-raters ICC of the projection method was 0.959 and 0.974. There was no correlation between the STVC and HTVC (P > 0.05). CONCLUSIONS: After ipsilateral wisdom teeth extraction, the volume of hard tissue on the extraction side reduces, and the volume of facial soft tissue does not change evidently. However, further research with large sample size is still needed. The STV measurement has excellent repeatability. It can be extended to other interested areas, including forehead, nose, paranasal, upper lip, lower lip and chin, which is meaningful in the field of orthodontics and orthopedics. TRIAL REGISTRATION: ChiCTR, ChiCTR1800018305 (11/09/2018), http://www.chictr.org.cn/showproj.aspx?proj=28868 .


Assuntos
Assistência Odontológica , Feminino , Humanos , Masculino , Queixo , Lábio , Projetos Piloto , Adulto
5.
BMC Musculoskelet Disord ; 23(1): 59, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039039

RESUMO

BACKGROUND: To evaluate lumbar mobility in various positions using upright left and right bending radiographs in patients with degenerative lumbar spondylolisthesis (DLS), as well as to assess the impact of lateral instability on patient-reported outcomes. METHODS: This study retrospectively reviewed a consecutive series of patients with DLS between January 2019 and October 2020. The enrolled patients were divided into two groups: the lateral instability group (group L) and non-lateral instability group (group NL). Translational and angular motion in both sagittal and coronal planes and patient-reported outcomes were compared between the two groups. RESULTS: There were 104 (59.8%) patients in group L and 70 (40.2%) patients in group NL, with an average age of 60.6 ± 7.8 years. Patients with a right bending posture in group L had a higher slip percentage (14.2 ± 7.4% vs 9.2 ± 3.2%, p = 0.01) and slip angle (6.3 ± 1.5° vs 2.2 ± 0.8°, p = 0.021). Compared with group NL, group L demonstrated significantly larger angular motion in the coronal plane (2.4 ± 1.3° vs 1.0 ± 0.7°, p = 0.008). Patients with lateral instability had worse preoperative back pain (6.1 ± 1.6 vs 2.7 ± 1.9, p = 0.01) and Oswestry Disability Index (ODI) scores (37.7 ± 5.5 vs 25.6 ± 2.6, p = 0.002). In terms of pain characteristics, group L was characterized by pain when getting out of a car, when rising from a chair, and when climbing stairs (all p values < 0.05). CONCLUSION: Lumbar lateral instability, that is, increased mobility in the coronal plane on lateral bending radiographs, translational and/or angular, correlates to more pronounced patient related symptoms in degenerative L4-5 spondylolisthesis. The existence of lumbar lateral instability leads to worse impacts on patient-reported outcomes when patients change their positions including getting out of a car, rising from a chair, and climbing stairs.


Assuntos
Degeneração do Disco Intervertebral , Espondilolistese , Idoso , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Região Lombossacral , Pessoa de Meia-Idade , Estudos Retrospectivos , Espondilolistese/diagnóstico por imagem
6.
Am J Orthod Dentofacial Orthop ; 161(3): e287-e295, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34924284

RESUMO

INTRODUCTION: A standardized procedure was proposed to control involuntary motion and other factors during the capture of structural light scanning that could influence the morphology of 3-dimensional facial models; interoperator reproducibility was evaluated. METHODS: Twenty subjects volunteered for facial scanning. Three researchers scanned each volunteer 3 times on the same day using the FaceScan structural light scanning system (Isravision, Darmstadt, Germany) and after the proposed procedure. Captures were done at 5-minute intervals. The 3 facial scans acquired by the same researcher were compared by reverse engineering software (Geomagic; 3D Systems, Rock Hill, SC). Six facial regions, including forehead, nose, paranasal, upper lip, lower lip and chin, and cheek, were divided. With the first scan as a reference, the other 2 scans were registered, and surface-to-surface distance maps were acquired to calculate the mean, standard deviation, and root mean squares (RMS) between 2 surfaces. The reproducibility between 3 researchers was then evaluated by a 1-way analysis of variance. RESULTS: The mean of 6 facial regions was close to 0. The RMS of lip regions were largest (0.48-0.53 mm), the forehead was smallest (0.21 mm), and the others ranged 0.37 mm to 0.42 mm. The standard deviation was slightly smaller than RMS and had the same trend of change. There was no significant difference in RMS among the 3 researchers (P >0.05). CONCLUSIONS: With the constraint of the standardized procedure, the morphologic reproducibility of facial models in 6 regions was satisfying.


Assuntos
Face , Imageamento Tridimensional , Face/anatomia & histologia , Face/diagnóstico por imagem , Humanos , Imageamento Tridimensional/métodos , Lábio/anatomia & histologia , Nariz/anatomia & histologia , Nariz/diagnóstico por imagem , Reprodutibilidade dos Testes
7.
Entropy (Basel) ; 21(1)2019 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33266775

RESUMO

In the practical application of quantum entanglement, entangled particles usually need to be distributed to many distant parties or stored in different quantum memories. In these processes, entangled particles unavoidably interact with their surrounding environments, respectively. We here systematically investigate the entanglement-decay laws of cat-like states under independent Pauli noises with unbalanced probability distribution of three kinds of errors. We show that the robustness of cat-like entangled states is not only related to the overall noise strength and error distribution parameters, but also to the basis of qubits. Moreover, we find that whether a multi-qubit state is more robust in the computational basis or transversal basis depends on the initial entanglement and number of qubits of the state as well as the overall noise strength and error distribution parameters of the environment. However, which qubit basis is conductive to enhancing the robustness of two-qubit states is only dependent on the error distribution parameters. These results imply that one could improve the intrinsic robustness of entangled states by simply transforming the qubit basis at the right moment. This robustness-improving method does not introduce extra particles and works in a deterministic manner.

8.
J Asian Nat Prod Res ; 18(12): 1138-1142, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27268250

RESUMO

Two new dammarane-type triterpenoid saponins, namely ginsenoside Rk6 (1) and ginsenoside-Rh22 (2), were isolated from notoginseng medicinal fungal substance. The structures of 1 and 2 were established as 3ß,6α,12ß,26-tetrahydroxydammar-20(21),24(25)(E)-diene-6-O-ß-D-glucopyranoside and 3ß,6α, 20(S)-trihydroxy-12(R),23(R)-expoxy-13(S),17(S)-dammar-24-ene-6-O-ß-D-glucopyranoside on the basis of spectroscopic analysis and chemical analysis, respectively.


Assuntos
Fungos/química , Ginsenosídeos/isolamento & purificação , Panax/microbiologia , Saponinas/isolamento & purificação , Triterpenos/isolamento & purificação , Ginsenosídeos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Raízes de Plantas/química , Rizoma/química , Saponinas/química , Estereoisomerismo , Triterpenos/química , Damaranos
9.
J Asian Nat Prod Res ; 18(9): 865-70, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27053377

RESUMO

Two new dammarane-type triterpenoid saponins, namely ginsenosides Rb4 (1) and Rb5 (2), were isolated from ginseng medicinal fungal substance. The structures of 1 and 2 were established as 3ß,12ß,20(S)-trihydroxydammar-24(25)-ene-3-O-[α-d-glucopyranosyl-(1→4)-ß-d-glucopyranosyl-(1→2)-ß-d-glucopyranosyl]-20-O-ß-d-glucopyranoside and 3ß,12ß,20(S)-trihydroxydammar-24(25)-ene-3-O-[α-d-glucopyranosyl-(1→4)-α-d-glucopyranosyl-(1→4)-ß-d-glucopyranosyl-(1→2)-ß-d-glucopyranosyl]-20-O-ß-d-glucopyranoside on the basis of spectroscopic analysis and chemical analysis, respectively.


Assuntos
Ginsenosídeos/isolamento & purificação , Panax/química , Saponinas/isolamento & purificação , Triterpenos/isolamento & purificação , Ginsenosídeos/química , Estrutura Molecular , Raízes de Plantas/química , Rizoma/química , Saponinas/química , Estereoisomerismo , Triterpenos/química , Damaranos
10.
J Oral Pathol Med ; 42(4): 315-21, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23121285

RESUMO

Oral lichen planus (OLP) is a common oral mucosal disease, which is generally considered a potentially malignant lesion. To identify efficiently prognostic biomarker, we investigated the microRNA-137 (miR-137) promoter methylation in OLP and compared with the samples from healthy volunteers and patients with oral squamous cell carcinoma (OSCC). A total of 20 OLP and 12 patients with OSCC as well as 10 healthy subjects were subjected to miR-137 promoter methylation analysis using methylation-specific PCR (MSP). To address the malignancy prediction potential from miR-137 promoter methylation status, methylation of the p16 gene, a well-known tumor suppressor, was investigated in the same samples. The p16 methylation and miR-137 promoter methylation were found to be 25% and 35% in patients with OLP, 50% and 58.3% in patients with OSCC, and 0% and 0% in healthy subjects, respectively. The differences between miR-137 and p16 methylation levels were statistically significant between healthy controls and patients. Methylation levels of the two promoters were also influenced by age, gender, and lesion duration. Interestingly, aberrant promoter methylation of the p16 and miR-137 genes was only found in the epithelium but not in the connective tissue from patients with OLP. This raises the possibility to use miR-137 methylation as a biomarker for malignant prediction in patients with OLP.


Assuntos
Carcinoma de Células Escamosas/genética , Líquen Plano Bucal/genética , MicroRNAs/genética , Neoplasias Bucais/genética , Regiões Promotoras Genéticas/genética , Adulto , Fatores Etários , Consumo de Bebidas Alcoólicas , Biomarcadores Tumorais/análise , Transformação Celular Neoplásica/genética , Tecido Conjuntivo/patologia , Inibidor p16 de Quinase Dependente de Ciclina/análise , Epitélio/patologia , Feminino , Genes p16 , Humanos , Líquen Plano Bucal/patologia , Masculino , Metilação , MicroRNAs/análise , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Lesões Pré-Cancerosas/genética , Fatores de Risco , Fatores Sexuais , Fatores de Tempo
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