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1.
Alzheimers Res Ther ; 16(1): 211, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39358805

RESUMO

BACKGROUND: Recent magnetic resonance imaging (MRI) studies have established that brain iron accumulation might accelerate cognitive decline in Alzheimer's disease (AD) patients. Both normal aging and AD are associated with cerebral atrophy in specific regions. However, no studies have investigated aging- and AD-selective iron deposition-related cognitive changes during normal aging. Here, we applied quantitative susceptibility mapping (QSM) to detect iron levels in cortical signature regions and assessed the relationships among iron, atrophy, and cognitive changes in older adults. METHODS: In this Taizhou Imaging Study, 770 older adults (mean age 62.0 ± 4.93 years, 57.5% women) underwent brain MRI to measure brain iron and atrophy, of whom 219 underwent neuropsychological tests nearly every 12 months for up to a mean follow-up of 2.68 years. Global cognition was assessed using the Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). Domain-specific cognitive scores were obtained from MoCA subscore components. Regional analyses were performed for cortical regions and 2 signature regions where atrophy affected by aging and AD only: Aging (AG) -specific and AD signature meta-ROIs. The QSM and cortical morphometry means of the above ROIs were also computed. RESULTS: Significant associations were found between QSM levels and cognitive scores. In particular, after adjusting for cortical thickness of regions of interest (ROIs), participants in the upper tertile of the cortical and AG-specific signature QSM exhibited worse ZMMSE than did those in the lower tertile [ ß = -0.104, p = 0.026; ß = -0.118, p = 0.021, respectively]. Longitudinal analysis suggested that QSM values in all ROIs might predict decline in ZMoCA and key domains such as attention and visuospatial function (all p < 0.05). Furthermore, iron levels were negatively correlated with classic MRI markers of cortical atrophy (cortical thickness, gray matter volume, and local gyrification index) in total, AG-specific signature and AD signature regions (all p < 0.05). CONCLUSION: AG- and AD-selective iron deposition was associated with atrophy and cognitive decline in elderly people, highlighting its potential as a neuroimaging marker for cognitive aging.


Assuntos
Atrofia , Encéfalo , Envelhecimento Cognitivo , Ferro , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Humanos , Feminino , Masculino , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Idoso , Ferro/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Atrofia/patologia , Envelhecimento Cognitivo/fisiologia , China , Envelhecimento/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo
2.
Biosensors (Basel) ; 14(5)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38785692

RESUMO

This study presents a biosensor fabricated based on integrated passive device (IPD) technology to measure microbial growth on solid media in real-time. Yeast (Pichia pastoris, strain GS115) is used as a model organism to demonstrate biosensor performance. The biosensor comprises an interdigital capacitor in the center with a helical inductive structure surrounding it. Additionally, 12 air bridges are added to the capacitor to increase the strength of the electric field radiated by the biosensor at the same height. Feasibility is verified by using a capacitive biosensor, and the change in capacitance values during the capacitance detection process with the growth of yeast indicates that the growth of yeast can induce changes in electrical parameters. The proposed IPD-based biosensor is used to measure yeast drop-added on a 3 mm medium for 100 h at an operating frequency of 1.84 GHz. The resonant amplitude of the biosensor varies continuously from 24 to 72 h due to the change in colony height during vertical growth of the yeast, with a maximum change of 0.21 dB. The overall measurement results also fit well with the Gompertz curve. The change in resonant amplitude between 24 and 72 h is then analyzed and reveals a linear relationship with time with a coefficient of determination of 0.9844, indicating that the biosensor is suitable for monitoring yeast growth. Thus, the proposed biosensor is proved to have potential in the field of microbial proliferation detection.


Assuntos
Técnicas Biossensoriais , Leveduras/crescimento & desenvolvimento
3.
Front Bioeng Biotechnol ; 12: 1398189, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38803847

RESUMO

Cytotoxicity assays are crucial for assessing the efficacy of drugs in killing cancer cells and determining their potential therapeutic value. Measurement of the effect of drug concentration, which is an influence factor on cytotoxicity, is of great importance. This paper proposes a cytotoxicity assay using microwave sensors in an end-point approach based on the detection of the number of live cells for the first time. In contrast to optical methods like fluorescent labeling, this research uses a resonator-type microwave biosensor to evaluate the effects of drug concentrations on cytotoxicity by monitoring electrical parameter changes due to varying cell densities. Initially, the feasibility of treating cells with ultrapure water for cell counting by a microwave biosensor is confirmed. Subsequently, inhibition curves generated by both the CCK-8 method and the new microwave biosensor for various drug concentrations were compared and found to be congruent. This agreement supports the potential of microwave-based methods to quantify cell growth inhibition by drug concentrations.

4.
Biosensors (Basel) ; 14(4)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38667173

RESUMO

Since different quantities of white blood cells (WBCs) in solution possess an adaptive osmotic pressure of cells, the WBCs themselves and in solution have similar concentrations, resulting in them having similar dielectric properties. Therefore, a microwave sensor could have difficulty in sensing the quantity variation when WBCs are in solution. This paper presents a highly sensitive, linear permittivity-inspired microwave biosensor for WBCs, counting through the evaporation method. Such a measurement method is proposed to record measurements after the cell solution is dripped onto the chip and is completely evaporated naturally. The proposed biosensor consists of an air-bridged asymmetric differential inductor and a centrally located circular fork-finger capacitor fabricated on a GaAs substrate using integrated passive fabrication technology. It is optimized to feature a larger sensitive area and improved Q-factor, which increases the effective area of interaction between cells and the electromagnetic field and facilitates the detection of their changes in number. The sensing relies on the dielectric properties of the cells and the change in the dielectric constant for different concentrations, and the change in resonance properties, which mainly represents the frequency shift, corresponds to the macroscopic change in the concentration of the cells. The microwave biosensors are used to measure biological samples with concentrations ranging from 0.25 × 106 to 8 × 106 cells per mL in a temperature (26.00 ± 0.40 °C) and humidity (54.40 ± 3.90 RH%) environment. The measurement results show a high sensitivity of 25.06 Hz/cells·mL-1 with a highly linear response of r2 = 0.99748. In addition, a mathematical modeling of individual cells in suspension is performed to estimate the dielectric constant of individual cells and further explain the working mechanism of the proposed microwave biosensor.


Assuntos
Técnicas Biossensoriais , Humanos , Contagem de Leucócitos , Leucócitos/citologia , Micro-Ondas
5.
ACS Sens ; 8(10): 3862-3872, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37752695

RESUMO

In this work, a new type, highly sensitive, and reusable nanoplastics (NPs) microwave detection method is proposed, which can be used to rapidly analyze NPs with different surface charges and sizes. The effective dielectric constant of NPs varies according to the different concentrations, particle sizes, and surface charges of NPs in aqueous solution. The feasibility of the microwave method for differential-charged NPs detection is verified using a complementary split ring resonator sensor manufactured on a cost-effective printed circuit board, which shows a high sensitivity only for positively charged NPs (PS-NH2) detection. To achieve microwave detection of both positively and negatively charged NPs (PS-SO3H), a microscale spiral-coupled resonator sensing chip is manufactured through integrated passive technology, which demonstrates extremely low detection limits and high sensitivity for both PS-NH2 and PS-SO3H, with different concentrations, particle sizes, and charges. In addition, for NPs solution doped with methyl orange, the device can still perform stable measurements, overcoming the inability of traditional NPs molecular element determination and optical detection methods to detect NPs aqueous solution with organic matter doping and color presence. The proposed microwave detection method could also be extended to sensing detection for detecting other hazardous environmental substances.


Assuntos
Microplásticos , Micro-Ondas
6.
World J Gastrointest Oncol ; 14(9): 1604-1621, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36187393

RESUMO

Hepatocellular carcinoma (HCC) is a highly heterogeneous, invasive, and conventional chemotherapy-insensitive tumor with unique biological characteristics. The main methods for the radical treatment of HCC are surgical resection or liver transplantation. However, recurrence rates are as high as 50% and 70% at 3 and 5 years after liver resection, respectively, and even in Milan-eligible recipients, the recurrence rate is approximately 20% at 5 years after liver transplantation. Therefore, reducing the postoperative recurrence rate is key to improving the overall outcome of liver cancer. This review discusses the risk factors for recurrence in patients with HCC radical surgical resection and adjuvant treatment options that may reduce the risk of recurrence and improve overall survival, including local adjuvant therapy (e.g., transcatheter arterial chemoembolization), adjuvant systemic therapy (e.g., molecular targeted agents and immunotherapy), and other adjuvant therapies (e.g., antiviral and herbal therapy). Finally, potential research directions that may change the paradigm of adjuvant therapy for HCC are analyzed.

7.
Drug Discov Today ; 27(5): 1350-1366, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35248748

RESUMO

The screening of compound-protein interactions (CPIs) is one of the most crucial steps in finding hit and lead compounds. Deep learning (DL) methods for CPI prediction can address intrinsic limitations of traditional HTS and virtual screening with the advantage of low cost and high efficiency. This review provides a comprehensive survey of DL-based CPI prediction. It first summarizes popular databases of small-molecule compounds, proteins and binding complexes. Then, it outlines classical representations of compounds and proteins in turn. After that, this review briefly introduces state-of-the-art DL-based models in terms of design paradigms and investigates their prediction performance. Finally, it indicates current challenges and trends toward better CPI prediction and sketches out crucial approaches toward practical applications.


Assuntos
Aprendizado Profundo , Bases de Dados Factuais , Descoberta de Drogas/métodos , Proteínas/metabolismo
8.
Yi Chuan ; 43(10): 980-987, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34702710

RESUMO

In the era of big data and precision medicine, large population cohort studies are one of the preferred designs for studying the etiology of chronic diseases, and cohort genetic resources have become important strategic resources of China. Promoting the standardized construction and utilization of cohort genetic resources can effectively promote the original innovation of research and technological development in the field of biomedicine, and make full use of the rich genetic resources of China. To provide a reference for the construction and utilization of genetic resources in the cohort research in China, we took the Taizhou Longitudinal Study (TZL) as an example and introduced the principles, methods, standard system, and practical experience of the collection, preservation, and shared utilization of genetic resources in the process of the cohort construction.


Assuntos
Genética Humana , China , Estudos de Coortes , Humanos , Estudos Longitudinais , Recursos Humanos
9.
Micromachines (Basel) ; 11(9)2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32878285

RESUMO

A stepped planar microstrip structure is proposed and demonstrated as a candidate of the ultra-wideband (UWB) antenna in the paper. In the structure, two L-shaped slots are introduced into the rectangular microstrip patch to broaden the current path at both edges of the radiating patch. The impedance bandwidth of the antenna can be extended by using the stepped impedance resonator (SIR) structure at one end of the radiation patch and connecting with the feed line. The symmetrical two I-shaped slots are loaded on the SIR microstrip to improve in-band performance and further widen the operating band. The proposed new structure can have an improvement in the in-band characteristics while extending the operating bandwidth. A broadband impedance bandwidth of 2.39 GHz to 13.78 GHz at S11 < -10 dB is demonstrated based on the proposed novel structure. The reflection coefficient and radiation characteristics are characterized in the paper. The tiny antenna, with the benefit of small area 36 mm × 23 mm, shows potential applications in ultra-wideband communication systems, wireless energy harvesting systems, and other wireless systems.

10.
Zhongguo Zhong Yao Za Zhi ; 43(13): 2831-2835, 2018 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-30111038

RESUMO

Field surveys and literatures show that Polygonati Rhizome (Huangjing) was firstly recorded in Shen Nong&s Herbal Classic, and widely used as a medicinal and edible plant. It has a long history of cultivation, and the researches on chemistry have made some progress. The future development is prospected on health market. But the Polygonati Rhizome industry has faced a lot of problems, including the resource depletion, unstable quality, low-tech in cultivation and germplasm confusion, unclear of functional composition, decentralized, small scaled and primary processing products. The suggestion for sustainable development are listed below. First, the relevant researches should focused on material basis and biological mechanism of core effects. To speed up the selection and breeding of improved varieties, ensure the supply of high-quality seedlings and eliminate the unauthentic species are the most important measures. Secondly, to strengthen the conservation and rational use of wild resources, break through the key technologies of high-quality artificial cultivation on light regulation, site control, density control and precision harvesting are also very important. Thirdly, to reveal the toxicity-reducing-and-efficacy-enhancing mechanism of processing, optimize the parameters and setup the standard operating procedure are indispensable. Fourthly, that full advantage of the root, leaf, flower and fruit resources should be strengthened for enlarged health products based on the development of exact functional factors. Above all, Polygonati Rhizome could be a growing market in the future driven by the technological innovation, cultural creativity, integration of three industries, brand strategy and internet+technique.


Assuntos
Rizoma , Melhoramento Vegetal , Folhas de Planta , Polygonatum , Desenvolvimento Sustentável
12.
J Org Chem ; 79(22): 10820-8, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25375772

RESUMO

Total synthesis of (±)-antroquinonol D, which is isolated from very expensive and rarely found Antrodia camphorata and which has potential anticancer properties, was achieved from 4-methoxyphenol. In addition, a Michael addition to dimethoxy cyclohexadienones was studied. The main step involved chelation and substrate-controlled diastereoselective reduction of cyclohexenone and lactonization. Lactone synthesis facilitated the diastereoselective reduction of ketone, which help control the desired stereochemistry at the crucial stereogenic center in the natural product. Other key reactions in the synthesis involved a Michael addition of dimethyl malonate on cyclohexadienone, dihydroxylation, and Wittig olefination. A sesquiterpene side chain was synthesized through coupling with geranyl phenyl sulfide and Bouveault-Blanc reduction.


Assuntos
Antineoplásicos/síntese química , Antrodia/química , Produtos Biológicos/química , Lactonas/síntese química , Ubiquinona/análogos & derivados , Antineoplásicos/química , Antineoplásicos/farmacologia , Lactonas/química , Estereoisomerismo , Ubiquinona/síntese química , Ubiquinona/química
13.
Zhongguo Zhong Yao Za Zhi ; 33(17): 2087-9, 2008 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19066046

RESUMO

OBJECTIVE: To reveal the relationship between the storage time of the bark of Magnolia officinalis and the content of phenols in it, and lay a theoretical foundation for the harvest, processing, management and storage. METHOD: The contents of magnolol and honokoiol in 15 bark samples, collected from the main producing areas in China, were determined in the time of freshly harvest and 3 and 10 years after respectively by HPLC method. RESULT: It showed that within a certain period of time, bark storage was favorable to conversion and accumulation of phenols, that the content of magnolol tended to increase from year 0 to year 3, then followed by slight decrease with years on account of volatilization of phenols, but was still higher when the bark was stored for 10 years than that that when the bark was freshly harvested, and the content of honokoiol still tended to increase when the bark had been stored for 10 years. CONCLUSION: The phenols in bark of M. officinalis is quite stable and the bark can be stored for 10 years or longer.


Assuntos
Compostos de Bifenilo/análise , Armazenamento de Medicamentos/métodos , Medicamentos de Ervas Chinesas/química , Lignanas/análise , Magnolia/química , Casca de Planta/química , Fatores de Tempo
14.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 25(8): 740-2, 2005 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16152837

RESUMO

OBJECTIVE: To observe the clinical effect of Pifubing Xuedu Pill (PXDP) combined with Diyin Tablet (DYT) in treating patients with psoriasis. METHODS: Sixty patients were divided into 2 groups by randomized controlled method. DYT was orally taken by all patients, while XDP was given additionally to patients in the treated group, the medication was continued for 1 month. The therapeutic effect, toxic and adverse reaction were observed. RESULTS: In the treated group, 7 patients were cured, 11 basically cured, 4 markedly effective, 7 improved, and 1 ineffective, with the clinical cured rate of 60.0% and the total effective rate 73.3%. In the control group, 3 were cured, 4 basically cured, 9 markedly effective, 10 improved, and 4 ineffective, with the clinical cured rate of 23.3% and the total effective rate 53.3%. No significant difference was shown in comparison of the total effective rate between the two groups (chi2 = 0.27, P > 0.05), however, significant difference was shown in comparison of the clinical cured rate (chi2 = 6.48, P < 0.05) between them. The toxic and adverse reaction in the treated group was obviously lower than those in the control group (t = 5.27, P <0.05). CONCLUSION: DYT combined with PXDP in treating psoriasis shows better therapeutic effect, with quicker initiation, lesser toxic and adverse reaction, and higher efficacy than using DYT alone.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Fitoterapia , Psoríase/tratamento farmacológico , Adolescente , Adulto , Quimioterapia Combinada , Feminino , Humanos , Masculino , Comprimidos
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