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1.
Nature ; 616(7955): 66-72, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36949195

RESUMO

Precise integration of two-dimensional (2D) semiconductors and high-dielectric-constant (k) gate oxides into three-dimensional (3D) vertical-architecture arrays holds promise for developing ultrascaled transistors1-5, but has proved challenging. Here we report the epitaxial synthesis of vertically aligned arrays of 2D fin-oxide heterostructures, a new class of 3D architecture in which high-mobility 2D semiconductor fin Bi2O2Se and single-crystal high-k gate oxide Bi2SeO5 are epitaxially integrated. These 2D fin-oxide epitaxial heterostructures have atomically flat interfaces and ultrathin fin thickness down to one unit cell (1.2 nm), achieving wafer-scale, site-specific and high-density growth of mono-oriented arrays. The as-fabricated 2D fin field-effect transistors (FinFETs) based on Bi2O2Se/Bi2SeO5 epitaxial heterostructures exhibit high electron mobility (µ) up to 270 cm2 V-1 s-1, ultralow off-state current (IOFF) down to about 1 pA µm-1, high on/off current ratios (ION/IOFF) up to 108 and high on-state current (ION) up to 830 µA µm-1 at 400-nm channel length, which meet the low-power specifications projected by the International Roadmap for Devices and Systems (IRDS)6. The 2D fin-oxide epitaxial heterostructures open up new avenues for the further extension of Moore's law.

2.
Nat Mater ; 22(7): 832-837, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36894772

RESUMO

The scaling of silicon-based transistors at sub-ten-nanometre technology nodes faces challenges such as interface imperfection and gate current leakage for an ultrathin silicon channel1,2. For next-generation nanoelectronics, high-mobility two-dimensional (2D) layered semiconductors with an atomic thickness and dangling-bond-free surfaces are expected as channel materials to achieve smaller channel sizes, less interfacial scattering and more efficient gate-field penetration1,2. However, further progress towards 2D electronics is hindered by factors such as the lack of a high dielectric constant (κ) dielectric with an atomically flat and dangling-bond-free surface3,4. Here, we report a facile synthesis of a single-crystalline high-κ (κ of roughly 16.5) van der Waals layered dielectric Bi2SeO5. The centimetre-scale single crystal of Bi2SeO5 can be efficiently exfoliated to an atomically flat nanosheet as large as 250 × 200 µm2 and as thin as monolayer. With these Bi2SeO5 nanosheets as dielectric and encapsulation layers, 2D materials such as Bi2O2Se, MoS2 and graphene show improved electronic performances. For example, in 2D Bi2O2Se, the quantum Hall effect is observed and the carrier mobility reaches 470,000 cm2 V-1 s-1 at 1.8 K. Our finding expands the realm of dielectric and opens up a new possibility for lowering the gate voltage and power consumption in 2D electronics and integrated circuits.


Assuntos
Grafite , Silício , Eletrônica , Semicondutores
4.
Neurosurg Focus ; 56(1): E15, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38163359

RESUMO

OBJECTIVE: Mixed-reality simulation is an emerging tool for creating anatomical models for preoperative planning. Its use in neurosurgical training (NT) has been limited because of the difficulty in real-time interactive teaching. This study describes the development of a patient-specific, interactive mixed-reality NT system. The authors took cases of intracranial tumor resection or neurovascular compression (NVC) as examples to verify the technical feasibility and efficacy of the mixed-reality NT system for residents' training and preoperative planning. METHODS: This study prospectively enrolled 40 patients who suffered from trigeminal neuralgia, hemifacial spasms, or intracranial tumors. The authors used a series of software programs to process the multimodal imaging data, followed by uploading the holographic models online. They used a HoloLens or a standard iOS device to download and display the holographic models for training. Ten neurosurgical residents with different levels of surgical experience were trained with this mixed-reality NT system. Change in surgical strategy was recorded, and a questionnaire survey was conducted to evaluate the efficacy of the mixed-reality NT system. RESULTS: The system allows the trainer and trainee to view the mixed-reality model with either a HoloLens or an iPad/iPhone simultaneously online at different locations. Interactive manipulation and instant updates were able to be achieved during training. A clinical efficacy validation test was conducted. The surgeons changed their exploration strategy in 48.3% of the NVC cases. For residents with limited experience in surgery, the exploration strategy for 75.0% of all patients with NVC was changed after the residents were trained with the mixed-reality NT system. Of the 60 responses for intracranial tumors, the trainee changed the surgical posture in 19 (31.7%) cases. The change of the location (p = 0.0338) and size (p = 0.0056) of craniotomy are significantly related to the experience of the neurosurgeons. CONCLUSIONS: The mixed-reality NT system is available for local or real-time remote neurosurgical resident training. It may effectively help neurosurgeons in patient-specific training and planning of surgery for cases of NVC and intracranial tumor. The authors expect the system to have a broader application in neurosurgery in the near future.


Assuntos
Neoplasias Encefálicas , Neurocirurgia , Humanos , Neurocirurgia/educação , Procedimentos Neurocirúrgicos/métodos , Simulação por Computador , Neurocirurgiões/educação , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia
5.
Sensors (Basel) ; 24(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38339612

RESUMO

Addressing conventional neurosurgical navigation systems' high costs and complexity, this study explores the feasibility and accuracy of a simplified, cost-effective mixed reality navigation (MRN) system based on a laser crosshair simulator (LCS). A new automatic registration method was developed, featuring coplanar laser emitters and a recognizable target pattern. The workflow was integrated into Microsoft's HoloLens-2 for practical application. The study assessed the system's precision by utilizing life-sized 3D-printed head phantoms based on computed tomography (CT) or magnetic resonance imaging (MRI) data from 19 patients (female/male: 7/12, average age: 54.4 ± 18.5 years) with intracranial lesions. Six to seven CT/MRI-visible scalp markers were used as reference points per case. The LCS-MRN's accuracy was evaluated through landmark-based and lesion-based analyses, using metrics such as target registration error (TRE) and Dice similarity coefficient (DSC). The system demonstrated immersive capabilities for observing intracranial structures across all cases. Analysis of 124 landmarks showed a TRE of 3.0 ± 0.5 mm, consistent across various surgical positions. The DSC of 0.83 ± 0.12 correlated significantly with lesion volume (Spearman rho = 0.813, p < 0.001). Therefore, the LCS-MRN system is a viable tool for neurosurgical planning, highlighting its low user dependency, cost-efficiency, and accuracy, with prospects for future clinical application enhancements.


Assuntos
Realidade Aumentada , Cirurgia Assistida por Computador , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Neuronavegação/métodos , Estudos de Viabilidade , Tomografia Computadorizada por Raios X , Lasers , Cirurgia Assistida por Computador/métodos , Imageamento Tridimensional/métodos
6.
J Asian Nat Prod Res ; 26(4): 510-518, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37705345

RESUMO

Eriocitrin is a flavonoid glycoside with strong antioxidant capacity that has a variety of pharmacological activities, such as hypolipidemic, anticancer and anti-inflammatory effects. We found that the gut microbiota could rapidly metabolize eriocitrin. By using LC/MSn-IT-TOF, we identified three metabolites of eriocitrin metabolized in the intestinal microbiota: eriodictyol-7-O-glucoside, eriodictyol, and dihydrocaffeic acid. By comparing these two metabolic pathways of eriocitrin (the gut microbiota and liver microsomes), the intestinal microbiota may be the primary metabolic site of eriocitrin metabolism. These findings provide a theoretical foundation for the study of pharmacologically active substances.


Assuntos
Flavanonas , Microbioma Gastrointestinal , Antioxidantes/farmacologia , Flavonoides/farmacologia , Biotransformação
7.
J Asian Nat Prod Res ; : 1-10, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869213

RESUMO

Liquiritigenin is a natural medicine. However, its inhibitory effect and its potential mechanism on bladder cancer (BCa) remain to be explored. It was found that it could be visualized that the transplanted tumours in the low-dose liquiritigenin -treated group and the high-dose liquiritigenin -treated group were smaller than those in the model group. Liquiritigenin treatment led to alterations in Lachnoclostridium, Escherichia-Shigella, Alistipes and Akkermansia. Non-targeted metabolomics analysis showed that a total of multiple differential metabolites were identified between the model group and the high-dose liquiritigenin-treated group. This provides a new direction and rationale for the antitumour effects of liquiritigenin.

8.
J Thromb Thrombolysis ; 56(3): 388-397, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37466848

RESUMO

Coronary microvascular endothelial cells (CMECs) react to changes in coronary blood flow and myocardial metabolites and regulate coronary blood flow by balancing vasoconstrictors-such as endothelin-1-and the vessel dilators prostaglandin, nitric oxide, and endothelium-dependent hyperpolarizing factor. Coronary microvascular endothelial cell dysfunction is caused by several cardiovascular risk factors and chronic rheumatic diseases that impact CMEC blood flow regulation, resulting in coronary microcirculation dysfunction (CMD). The mechanisms of CMEC dysfunction are not fully understood. However, the following could be important mechanisms: the overexpression and activation of nicotinamide adenine dinucleotide phosphate oxidase (Nox), and mineralocorticoid receptors; the involvement of reactive oxygen species (ROS) caused by a decreased expression of sirtuins (SIRT3/SIRT1); forkhead box O3; and a decreased SKCA/IKCA expression in the endothelium-dependent hyperpolarizing factor electrical signal pathway. In addition, p66Shc is an adapter protein that promotes oxidative stress; although there are no studies on its involvement with cardiac microvessels, it is possible it plays an important role in CMD.


Assuntos
Isquemia Miocárdica , Doenças Vasculares , Humanos , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Microcirculação , Células Endoteliais/metabolismo , Doenças Vasculares/metabolismo , Vasos Coronários , Endotélio Vascular/metabolismo
9.
Nano Lett ; 22(9): 3770-3776, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35467885

RESUMO

High-mobility and air-stable two-dimensional (2D) Bi2O2Se semiconductor holds promise as an alternative fast channel material for next-generation transistors. However, one of the key challenges remaining in 2D Bi2O2Se is to prepare high-quality crystals to fabricate the high-performance transistors with a high on-state current density. Here, we present the free-standing growth of strain-free 2D Bi2O2Se crystals. An ultrahigh Hall mobility of 160 000 cm2 V-1 s-1 is measured in strain-free Bi2O2Se crystals at 2 K, which enables the observation of Shubnikov-de Haas quantum oscillations and shows substantially higher (>4 times) mobility over previous in-plane 2D crystals. The fabricated 2D transistors feature an on-off current ratio of ∼106 and a record-high on-state current density of ∼1.33 mA µm-1, which is comparable to that of commercial Si and Ge n-type field-effect transistors (FETs) for similar channel length. Strain-free 2D Bi2O2Se provides a promising material platform for studying novel quantum phenomena and exploration of high-performance low-power electronics.

10.
Int J Mol Sci ; 24(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38139020

RESUMO

Organic phosphorus (OP) is an essential component of the soil P cycle, which contributes to barley nutrition after its mineralization into inorganic phosphorus (Pi). However, the dynamics of OP utilization in the barley rhizosphere remain unclear. In this study, phytin was screened out from six OP carriers, which could reflect the difference in OP utilization between a P-inefficient genotype Baudin and a P-efficient genotype CN4027. The phosphorus utilization efficiency (PUE), root morphological traits, and expression of genes associated with P utilization were assessed under P deficiency or phytin treatments. P deficiency resulted in a greater root surface area and thicker roots. In barley fed with phytin as a P carrier, the APase activities of CN4027 were 2-3-fold lower than those of Baudin, while the phytase activities of CN4027 were 2-3-fold higher than those of Baudin. The PUE in CN4027 was mainly enhanced by activating phytase to improve the root absorption and utilization of Pi resulting from OP mineralization, while the PUE in Baudin was mainly enhanced by activating APase to improve the shoot reuse capacity. A phosphate transporter gene HvPHT1;8 regulated P transport from the roots to the shoots, while a purple acid phosphatase (PAP) family gene HvPAPhy_b contributed to the reuse of P in barley.


Assuntos
6-Fitase , Hordeum , Fósforo/metabolismo , Hordeum/genética , Hordeum/metabolismo , 6-Fitase/metabolismo , Ácido Fítico/metabolismo , Genótipo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
11.
Neurosurg Focus ; 52(6): E3, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35921180

RESUMO

OBJECTIVE: To increase access to health interventions and healthcare services for patients in resource-constrained settings, strategies such as telemedicine must be implemented for the allocation of medical resources across geographic boundaries. Telecollaboration is the dominant form of surgical telemedicine. In this study, the authors report and evaluate a novel mobile internet-based mixed-reality interactive telecollaboration (MIMIT) system as a new paradigm for telemedicine and validate its clinical feasibility. METHODS: The application of this system was demonstrated for long-distance, real-time collaboration of neuroendoscopic procedures. The system consists of a local video processing workstation, a head-mounted mixed-reality display device, and a mobile remote device, connected over mobile internet (4G or 5G), allowing global point-to-point communication. Using this system, 20 cases of neuroendoscopic surgery were performed and evaluated. The system setup, composite video latency, technical feasibility, clinical implementation, and future potential business model were analyzed and evaluated. RESULTS: The MIMIT system allows two surgeons to perform complex visual and verbal communication during the operation. The average video delay time is 184.25 msec (range 160-230 msec) with 4G mobile internet, and 23.25 msec (range 20-26 msec) with 5G mobile internet. Excellent image resolution enabled remote neurosurgeons to visualize all critical anatomical structures intraoperatively. Remote instructors could easily make marks on the surgical view; then the composite image, as well as the audio conversation, was transferred to the local surgeon. In this way, a real-time, long-distance collaboration can occur. This system was used for 20 neuroendoscopic surgeries in various cities in China and even across countries (Boston, Massachusetts, to Jingzhou, China). Its simplicity and practicality have been recognized by both parties, and there were no technically related complications recorded. CONCLUSIONS: The MIMIT system allows for real-time, long-distance telecollaborative neuroendoscopic procedures and surgical training through a commercially available and inexpensive system. It enables remote experts to implement real-time, long-distance intraoperative interaction to guide inexperienced local surgeons, thus integrating the best medical resources and possibly promoting both diagnosis and treatment. Moreover, it can popularize and improve neurosurgical endoscopy technology in more hospitals to benefit more patients, as well as more neurosurgeons.


Assuntos
Neuroendoscopia , Telemedicina , Estudos de Viabilidade , Humanos , Internet , Neurocirurgiões
12.
J Neurooncol ; 151(2): 157-171, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33128099

RESUMO

PURPOSE: Long noncoding RNAs (LncRNAs) are essential epigenetic regulators with critical roles in tumor initiation and malignant progression; however, the mechanism by which aberrantly expressed lncRNA RP11-84E24.3 regulates the pathogenesis of glioma is not fully understood. Here, we investigate the function of lncRNA RP11-84E24.3 in glioma onset and progression as well as identify a molecular pathway regulated by this lncRNA. METHODS: Differentially expressed lncRNAs related to glioma were identified. The aberrant expression of lncRNA RP11-84E24.3 was verified in samples from patients with glioma as well as glioma cell lines. The role of lncRNA RP11-8424.3 in proliferation, apoptosis, migration, and invasion was assessed using gain- and loss-of function approaches, EdU incorporation, flow cytometry, wound healing and Transwell invasion assays. Western blot analysis was utilized to examine the expression of proteins associated with epithelial-to-mesenchymal transition (EMT). The interaction between lncRNA RP11-84E24.3, TFAP2C and SNAI1 was confirmed using RNA pull-down, ChIP and luciferase reporter assays. RESULTS: LncRNA RP11-84E24.3 was up-regulated in both glioma tissues and cell lines. LncRNA RP11-84E24.3 overexpression enhanced the proliferation, migration and invasion of glioma cells while reducing apoptosis. This was associated with a decrease in E-cadherin expression and an increase in N-cadherin and Vimentin expression. LncRNA RP11-84E24.3 directly targeted TFAP2C protein, resulting in increased SNAI1 expression. Knockdown of TFAP2C or SNAI1 reversed the effects of lncRNA RP11-84E24.3 overexpression, while silencing lncRNA RP11-84E24.3 inhibited tumor formation of glioma cells in vivo. CONCLUSIONS: LncRNA RP11-84E24.3 increased SNAI1 expression by forming a complex with TFAP2C protein, promoting EMT in glioma cells and tumor formation.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Transição Epitelial-Mesenquimal , Glioma/patologia , RNA Longo não Codificante/genética , Fatores de Transcrição da Família Snail/metabolismo , Fator de Transcrição AP-2/metabolismo , Adulto , Animais , Apoptose , Biomarcadores Tumorais/genética , Carcinogênese/genética , Carcinogênese/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Glioma/metabolismo , Humanos , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Prognóstico , Fatores de Transcrição da Família Snail/genética , Fator de Transcrição AP-2/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Proc Natl Acad Sci U S A ; 115(37): 9145-9150, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-30150389

RESUMO

One of the characteristics of topological materials is their nontrivial Berry phase. Experimental determination of this phase largely relies on a phase analysis of quantum oscillations. We study the angular dependence of the oscillations in a Dirac material [Formula: see text] and observe a striking spin-zero effect (i.e., vanishing oscillations accompanied with a phase inversion). This indicates that the Berry phase in [Formula: see text] remains nontrivial for arbitrary field direction, in contrast with previous reports. The Zeeman splitting is found to be proportional to the magnetic field based on the condition for the spin-zero effect in a Dirac band. Moreover, it is suggested that the Dirac band in [Formula: see text] is likely transformed into a line node other than Weyl points for the field directions at which the spin zero occurs. The results underline a largely overlooked spin factor when determining the Berry phase from quantum oscillations.

14.
Sensors (Basel) ; 21(5)2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33804518

RESUMO

This paper focuses on 6Dof object pose estimation from a single RGB image. We tackle this challenging problem with a two-stage optimization framework. More specifically, we first introduce a translation estimation module to provide an initial translation based on an estimated depth map. Then, a pose regression module combines the ROI (Region of Interest) and the original image to predict the rotation and refine the translation. Compared with previous end-to-end methods that directly predict rotations and translations, our method can utilize depth information as weak guidance and significantly reduce the searching space for the subsequent module. Furthermore, we design a new loss function function for symmetric objects, an approach that has handled such exceptionally difficult cases in prior works. Experiments show that our model achieves state-of-the-art object pose estimation for the YCB- video dataset (Yale-CMU-Berkeley).

15.
Biotechnol Lett ; 42(8): 1535-1545, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32246347

RESUMO

OBJECTIVE: Although the extracellular polysaccharides have been analyzed in the previous period, the biochemical, enzymological characters and stimulation and inhibition effect on glucansucrase are not fully understood. RESULTS: After three steps purification, salting out, DEAE-Sepharose and Sephadex G-75, the final specific activity was 264.84 U/mg protein with 4.31-fold. The SDS-PAGE analysis of fraction gave a single band 170.35 kDa in the stained gel. The active band was analyzed with LC-MS/MS to identify glucansucrase. The highest coverage rate of dextransucrase from Leu. citreum (ACY92456.2) was 55.60%, the results were speculated that the glucansucrase secreted from Leu. citreum B-2 may be a novel glucansucrase. The purified enzyme was optimally active at 20-30 °C and pH 6.0-8.0. Metal ions K+, Na+, Ca2+, Mn2+, Mg2+, and Cr+ had an apparent stimulating effect on enzyme activity, especially in divalent ions Ca2+ and Mn2+, the residual activities were higher than 200%. In a reverse, Hg+, acetonitrile, SDS, salt, and guanidine expressed inhibition effect on enzyme residual activity. The KM and Vmax were detected to be 4.82 mM and 0.97 U/mg, respectively. CONCLUSION: All these data collectively indicate that B-2 glucansucrase is a novel one, which have good properties and may applied to new food areas.


Assuntos
Proteínas de Bactérias , Glicosiltransferases , Leuconostoc/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Estabilidade Enzimática , Glicosiltransferases/química , Glicosiltransferases/isolamento & purificação , Glicosiltransferases/metabolismo , Concentração de Íons de Hidrogênio , Cinética , Cloreto de Sódio , Ureia
16.
Zhongguo Zhong Yao Za Zhi ; 45(11): 2552-2559, 2020 Jun.
Artigo em Zh | MEDLINE | ID: mdl-32627488

RESUMO

Scutellariae Radix(Huangqin) is a well-known traditional Chinese medicine(TCM) used for the treatment of clearing heat in clinical application. It is bitter-cold by using directly, but the bitter-cold property can be relieved after wine-frying. The study of taste changes before and after wine-frying of Scutellariae Radix is of great significance in identifying Scutellariae Radix and wine-processed Scutellariae Radix and clarifying the traditional theory of wine-processing. In this experiment, 10 batches of Scutellariae Radix and wine-processed Scutellariae Radix were prepared. The contents of 5 flavonoids were determined by high performance liquid chromatography(HPLC), and principal component analysis(PCA) was performed with 5 flavonoids as variables. As a result, the contents were different in different batches of Scutellariae Radix, but Scutellariae Radix and wine-processed Scutellariae Radix could not be distinguished. Five sensory attributes(sour, salty, fresh, sweet, and bitter) were evaluated by artificial tasting, and the response values of 7 sensors(AHS, AHS, PKS, CTS, NMS, CPS, ANS, SCS) representing the taste of pieces were detected by electronic tongue. The correlation between sensory evaluation and response values of the electronic tongue were analyzed, and the results showed that the sensory evaluation of sour, salty, fresh, sweet, bitter and AHS, CTS, NMS, ANS, SCS sensors had different degrees of correlation, indicating that the electronic tongue technology can be used as an alternative to artificial taste and can serve as a means for quantifying the taste, and it can be used to evaluate the taste of TCM pieces. The taste method was used to analyze the response values of the electronic tongue, and the results showed that the bitterness of wine-processed Scutellariae Radix decreased and the salty taste increased. PCA was used to analyze taste changes before and after wine-processed Scutellariae Radix, and the results showed that taste differences between 2 pieces were divided into 2 categories. PCA loading scattering plots showed that response of saltiness and bitterness were the major factors to affect overall taste in Scutellariae Radix and wine-processed Scutellariae Radix. Based on electronic tongue response values, the Fisher discriminant model for Scutellariae Radix and wine-processed Scutellariae Radix was established, which showed that it could effectively discriminate them with a recognition rate of 100%. The experimental results showed that the electronic tongue combined with multivariate statistical analysis can be used to evaluate taste of TCM, at the same time, it could provide a fast and simple method for identifying different processed products.


Assuntos
Scutellaria baicalensis , Vinho/análise , Cromatografia Líquida de Alta Pressão , Medicina Tradicional Chinesa , Paladar
17.
Zhongguo Zhong Yao Za Zhi ; 44(20): 4467-4475, 2019 Oct.
Artigo em Zh | MEDLINE | ID: mdl-31872634

RESUMO

Scutellariae Radix is one of the commonly used heat-clearing and damp-drying drugs in clinical practice. Establishment of the quality evaluation system for Scutellariae Radix is of great significance to ensure safety and effectiveness of clinical drug use.Scutellariae Radix pieces were prepared under different processing conditions with 3 softening methods: boiling,atmospheric steaming and pressurized steaming. High performance liquid chromatography( HPLC) method was used to determine the content of five flavonoids in Scutellariae Radix,and L*,a*,b*values representing color chromaticity of Scutellariae Radix powder were measured by colorimeter,then total color value E*was calculated. Simple correlation and canonical correlation analysis was used to explore the correlation between color of Scutellariae Radix powder and content of five flavonoids. The results showed that the contents of baicalin and wogonoside were significantly positively correlated with L*,b*and E*values,but negatively correlated with a*value. The contents of wogonin,apigenin,and melaleuca A were positively correlated with a*value,but negatively correlated with L*,b*,and E*values( P<0. 01). There was a significant negative correlation between the content of flavonoid glycosides and flavonoid aglycones( P<0. 01).All of these indicated that the color of Scutellariae Radix powder was significantly correlated with content of five flavonoids. The experiment results proved that when color difference between Huangqin pieces and medicinal materials was kept at ΔL*<6,Δb*<3,ΔE*<6,the total amount of the two glycosides in the pieces was about ±1. 5% of the medicinal materials; in this case,the total amount of the two glycosides was relatively high and stable,indicating that the color of Huangqin decoction pieces is a concrete manifestation of its intrinsic quality,and the chromaticity value detected by colorimeter can be used as a means to quickly evaluate the quality of Scutellariae Radix pieces. The results provide a new detection index for the characteristic quality evaluation system of Scutellariae Radix pieces.


Assuntos
Medicamentos de Ervas Chinesas , Scutellaria baicalensis , Cromatografia Líquida de Alta Pressão , Flavonoides
19.
Nutrients ; 16(4)2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38398843

RESUMO

The associations of dynapenic abdominal obesity and transitions with frailty progression remain unclear among middle-aged and older adults. We included 6937 participants from the China Health and Retirement Longitudinal Study (CHARLS) and 3735 from the English Longitudinal Study of Aging (ELSA). Participants were divided into non-dynapenia and non-abdominal obesity (ND/NAO), abdominal obesity alone (AO), dynapenia alone (D), and dynapenic abdominal obesity (D/AO). Frailty status was assessed by the frailty index (FI), and a linear mixed-effect model was employed to analyze the associations of D, AO, D/AO, and transitions with frailty progression. Participants with AO, D, and D/AO had increased FI progression compared with ND/NAO in both cohorts. D/AO possessed the greatest additional annual FI increase of 0.383 (95% CI: 0.152 to 0.614), followed by D and AO in the CHARLS. Participants with D in the ELSA had the greatest magnitude of accelerated FI progression. Participants who transitioned from ND/NAO to D and from AO to D/AO presented accelerated FI progression in the CHARLS and ELSA. In conclusion, dynapenic abdominal obesity, especially for D/AO and D, presented accelerated frailty progression. Our findings highlighted the essential intervention targets of dynapenia and abdominal obesity for the prevention of frailty progression.


Assuntos
Fragilidade , Obesidade Abdominal , Pessoa de Meia-Idade , Humanos , Idoso , Obesidade Abdominal/complicações , Obesidade Abdominal/epidemiologia , Estudos Longitudinais , Fragilidade/epidemiologia , Fragilidade/complicações , Circunferência da Cintura , Obesidade/complicações , Obesidade/epidemiologia , Força da Mão
20.
ACS Biomater Sci Eng ; 10(3): 1190-1206, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38343186

RESUMO

Cardiovascular disease poses a significant threat to human health in today's society. A major contributor to cardiovascular disease is atherosclerosis (AS). The development of plaque in the affected areas involves a complex pathological environment, and the disease progresses rapidly. Nanotechnology, combined with emerging diagnostic and treatment methods, offers the potential for the management of this condition. This paper presents the latest advancements in environment-intelligent responsive controlled-release nanoparticles designed specifically for the pathological environment of AS, which includes characteristics such as low pH, high reactive oxygen species levels, high shear stress, and multienzymes. Additionally, the paper summarizes the applications and features of nanotechnology in interventional therapy for AS, including percutaneous transluminal coronary angioplasty and drug-eluting stents. Furthermore, the application of nanotechnology in the diagnosis of AS shows promising real-time, accurate, and continuous effects. Lastly, the paper explores the future prospects of nanotechnology, highlighting the tremendous potential in the diagnosis and treatment of atherosclerotic diseases, especially with the ongoing development in nano gas, quantum dots, and Metal-Organic Frameworks materials.


Assuntos
Angioplastia Coronária com Balão , Aterosclerose , Doenças Cardiovasculares , Stents Farmacológicos , Nanopartículas , Humanos , Aterosclerose/diagnóstico , Aterosclerose/terapia , Aterosclerose/patologia , Nanopartículas/uso terapêutico
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