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1.
Circ Res ; 131(5): 424-441, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35899624

RESUMO

BACKGROUND: Inflamed endothelial cells (ECs) trigger atherogenesis, especially at arterial regions experiencing disturbed blood flow. UCP2 (Uncoupling protein 2), a key mitochondrial antioxidant protein, improves endothelium-dependent relaxation in obese mice. However, whether UCP2 can be regulated by shear flow is unknown, and the role of endothelial UCP2 in regulating inflammation and atherosclerosis remains unclear. This study aims to investigate the mechanoregulation of UCP2 expression in ECs and the effect of UCP2 on endothelial inflammation and atherogenesis. METHODS: In vitro shear stress simulation system was used to investigate the regulation of UCP2 expression by shear flow. EC-specific Ucp2 knockout mice were used to investigate the role of UCP2 in flow-associated atherosclerosis. RESULTS: Shear stress experiments showed that KLF2 (Krüppel-like factor 2) mediates fluid shear stress-dependent regulation of UCP2 expression in human aortic and human umbilical vein ECs. Unidirectional shear stress, statins, and resveratrol upregulate whereas oscillatory shear stress and proinflammatory stimuli inhibit UCP2 expression through altered KLF2 expression. KLF2 directly binds to UCP2 promoter to upregulate its transcription in human umbilical vein ECs. UCP2 knockdown induced expression of genes involved in proinflammatory and profibrotic signaling, resulting in a proatherogenic endothelial phenotype. EC-specific Ucp2 deletion promotes atherogenesis and collagen production. Additionally, we found endothelial Ucp2 deficiency aggravates whereas adeno-associated virus-mediated EC-Ucp2 overexpression inhibits carotid atherosclerotic plaque formation in disturbed flow-enhanced atherosclerosis mouse model. RNA-sequencing analysis revealed FoxO1 (forkhead box protein O1) as the major proinflammatory transcriptional regulator activated by UCP2 knockdown, and FoxO1 inhibition reduced vascular inflammation and disturbed flow-enhanced atherosclerosis. We showed further that UCP2 level is critical for phosphorylation of AMPK (AMP-activated protein kinase), which is required for UCP2-induced inhibition of FoxO1. CONCLUSIONS: Altogether, our studies uncover that UCP2 is novel mechanosensitive gene under the control of fluid shear stress and KLF2 in ECs. UCP2 expression is critical for endothelial proinflammatory response and atherogenesis. Therapeutic strategies enhancing UCP2 level may have therapeutic potential against atherosclerosis.


Assuntos
Aterosclerose , Placa Aterosclerótica , Proteína Desacopladora 2/metabolismo , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Células Cultivadas , Endotélio/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamação/genética , Inflamação/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Camundongos , Placa Aterosclerótica/metabolismo , Estresse Mecânico
2.
BMC Med Imaging ; 24(1): 121, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789936

RESUMO

OBJECTIVES: At present, there are many limitations in the evaluation of lymph node metastasis of lung adenocarcinoma. Currently, there is a demand for a safe and accurate method to predict lymph node metastasis of lung cancer. In this study, radiomics was used to accurately predict the lymph node status of lung adenocarcinoma patients based on contrast-enhanced CT. METHODS: A total of 503 cases that fulfilled the analysis requirements were gathered from two distinct hospitals. Among these, 287 patients exhibited lymph node metastasis (LNM +) while 216 patients were confirmed to be without lymph node metastasis (LNM-). Using both traditional and deep learning methods, 22,318 features were extracted from the segmented images of each patient's enhanced CT. Then, the spearman test and the least absolute shrinkage and selection operator were used to effectively reduce the dimension of the feature data, enabling us to focus on the most pertinent features and enhance the overall analysis. Finally, the classification model of lung adenocarcinoma lymph node metastasis was constructed by machine learning algorithm. The Accuracy, AUC, Specificity, Precision, Recall and F1 were used to evaluate the efficiency of the model. RESULTS: By incorporating a comprehensively selected set of features, the extreme gradient boosting method (XGBoost) effectively distinguished the status of lymph nodes in patients with lung adenocarcinoma. The Accuracy, AUC, Specificity, Precision, Recall and F1 of the prediction model performance on the external test set were 0.765, 0.845, 0.705, 0.784, 0.811 and 0.797, respectively. Moreover, the decision curve analysis, calibration curve and confusion matrix of the model on the external test set all indicated the stability and accuracy of the model. CONCLUSIONS: Leveraging enhanced CT images, our study introduces a noninvasive classification prediction model based on the extreme gradient boosting method. This approach exhibits remarkable precision in identifying the lymph node status of lung adenocarcinoma patients, offering a safe and accurate alternative to invasive procedures. By providing clinicians with a reliable tool for diagnosing and assessing disease progression, our method holds the potential to significantly improve patient outcomes and enhance the overall quality of clinical practice.


Assuntos
Adenocarcinoma de Pulmão , Aprendizado Profundo , Neoplasias Pulmonares , Metástase Linfática , Tomografia Computadorizada por Raios X , Humanos , Metástase Linfática/diagnóstico por imagem , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Masculino , Feminino , Tomografia Computadorizada por Raios X/métodos , Pessoa de Meia-Idade , Idoso , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Adulto , Radiômica
3.
Med Res Rev ; 43(6): 2086-2114, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37119045

RESUMO

The prevalence of cardiovascular disease (CVD) has been rising due to sedentary lifestyles and unhealthy dietary patterns. Peroxisome proliferator-activated receptor α (PPARα) is a nuclear receptor regulating multiple biological processes, such as lipid metabolism and inflammatory response critical to cardiovascular homeostasis. Healthy endothelial cells (ECs) lining the lumen of blood vessels maintains vascular homeostasis, where endothelial dysfunction associated with increased oxidative stress and inflammation triggers the pathogenesis of CVD. PPARα activation decreases endothelial inflammation and senescence, contributing to improved vascular function and reduced risk of atherosclerosis. Phenotypic switch and inflammation of vascular smooth muscle cells (VSMCs) exacerbate vascular dysfunction and atherogenesis, in which PPARα activation improves VSMC homeostasis. Different immune cells participate in the progression of vascular inflammation and atherosclerosis. PPARα in immune cells plays a critical role in immunological events, such as monocyte/macrophage adhesion and infiltration, macrophage polarization, dendritic cell (DC) embedment, T cell activation, and B cell differentiation. Cardiomyocyte dysfunction, a major risk factor for heart failure, can also be alleviated by PPARα activation through maintaining cardiac mitochondrial stability and inhibiting cardiac lipid accumulation, oxidative stress, inflammation, and fibrosis. This review discusses the current understanding and future perspectives on the role of PPARα in the regulation of the cardiovascular system as well as the clinical application of PPARα ligands.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Sistema Cardiovascular , Humanos , PPAR alfa/agonistas , PPAR alfa/metabolismo , Células Endoteliais/metabolismo , Aterosclerose/tratamento farmacológico , Inflamação/tratamento farmacológico , Doenças Cardiovasculares/tratamento farmacológico
4.
BMC Plant Biol ; 23(1): 353, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37420192

RESUMO

BACKGROUND: Wheat (Triticum aestivum L.) is a major cereal crop that is grown worldwide, and it is highly dependent on sufficient N supply. The molecular mechanisms associated with nitrate uptake and assimilation are still poorly understood in wheat. In plants, NRT2 family proteins play a crucial role in NO3- acquisition and translocation under nitrate limited conditions. However, the biological functions of these genes in wheat are still unclear, especially their roles in NO3- uptake and assimilation. RESULTS: In this study, a comprehensive analysis of wheat TaNRT2 genes was conducted using bioinformatics and molecular biology methods, and 49 TaNRT2 genes were identified. A phylogenetic analysis clustered the TaNRT2 genes into three clades. The genes that clustered on the same phylogenetic branch had similar gene structures and nitrate assimilation functions. The identified genes were further mapped onto the 13 wheat chromosomes, and the results showed that a large duplication event had occurred on chromosome 6. To explore the TaNRT2 gene expression profiles in wheat, we performed transcriptome sequencing after low nitrate treatment for three days. Transcriptome analysis revealed the expression levels of all TaNRT2 genes in shoots and roots, and based on the expression profiles, three highly expressed genes (TaNRT2-6A.2, TaNRT2-6A.6, and TaNRT2-6B.4) were selected for qPCR analysis in two different wheat cultivars ('Mianmai367' and 'Nanmai660') under nitrate-limited and normal conditions. All three genes were upregulated under nitrate-limited conditions and highly expressed in the high nitrogen use efficiency (NUE) wheat 'Mianmai367' under low nitrate conditions. CONCLUSION: We systematically identified 49 NRT2 genes in wheat and analysed the transcript levels of all TaNRT2s under nitrate deficient conditions and over the whole growth period. The results suggest that these genes play important roles in nitrate absorption, distribution, and accumulation. This study provides valuable information and key candidate genes for further studies on the function of TaNRT2s in wheat.


Assuntos
Nitratos , Triticum , Nitratos/metabolismo , Triticum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Nitrogênio/metabolismo
5.
Opt Express ; 31(8): 12189-12199, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37157383

RESUMO

A leaky-wave antenna (LWA) based on reconfigurable spoof surface plasmon polaritons (SSPP) is proposed for beam scanning in the Ka band, which consists of a reconfigurable SSPP waveguide and a periodic array of metal rectangular split rings. Both numerical simulations and experimental measurements show that the reconfigurable SSPP-fed LWA has good performance in the frequency range from 25 to 30 GHz. Specifically, as the bias voltage changes from 0 to 15 V, we can achieve the maximum sweep range of 24° at a single frequency and 59° at multiple frequency points, respectively. Owing to the wide-angle beam-steering feature, as well as the field confinement and wavelength compression properties derived from the SSPP architecture, the proposed SSPP-fed LWA possesses great potential applications in the compact and miniaturized devices and systems of the Ka band.

7.
BMC Nurs ; 22(1): 360, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803355

RESUMO

BACKGROUND: Workplace bullying experienced by clinical nurses is a critical and pervasive issue that not only detrimentally impacts nurses but also poses a significant threat to the overall quality of nursing services and patient care. This study aimed to determine the mediating role of organizational commitment in the relationship between workplace bullying and turnover intention among clinical nurses in China. METHODS: Participants were recruited from 40 hospitals in various provinces of China from December 2, 2021 to February 25, 2023, using convenience sampling. After obtaining hospital ethical approval and participants' informed consent, clinical nurses (n = 585) from different nursing departments in different hospitals completed the questionnaire. The Socio-demographic Questionnaire, Negative Acts Qestionnaire, Chinese Workers' Organizational Commitment Scale and Turnover Intention Questionnaire were used to collect general demographic data of nurses and assess workplace bullying they experienced, their level of organizational commitment and turnover intention. Descriptive statistics, Pearson correlation analyses and structural equation model were adopted to analyze the data. RESULTS: Pearson's correlation analysis showed that that workplace bullying was significantly negatively correlated with organizational commitment (r = - 0.512, P<0.01) and significantly positively correlated with turnover intention (r = 0.558, P<0.01), organizational commitment was significantly negatively correlated with turnover intention (r = - 0.539, P<0.01). Mediation analysis indicated organizational commitment partially mediated the association between workplace bullying and turnover intention. The total effect (ß = 0.69) of workplace bullying on turnover intention consisted of its direct effect (ß = 0.41) and the indirect effect mediated through organizational commitment (ß = 0.280), with the mediating effect accounting for 40.58% of the total effect. CONCLUSION: Organizational commitment mediated the associations of workplace bullying and turnover intention. Therefore, healthcare organizations and nursing managers should develop appropriate strategies to enhance nurses' organizational commitment in order to reduce their turnover intention.

8.
Zhongguo Zhong Yao Za Zhi ; 48(11): 3000-3013, 2023 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-37381974

RESUMO

Huocao(a traditional Chinese herbal medicine) moxibustion is a characteristic technology in Yi medicine suitable for cold-dampness diseases. Huocao, as the moxibustion material, is confusedly used in clinical practice and little is known about its quality control. In this study, UPLC method was used to establish the chemical fingerprint of non-volatile components in Huocao, and the contents of eight phenolic acids such as chlorogenic acid were determined. Multivariate statistical analysis was performed to obtain the indicator components of Huocao for quality evaluation, and thus a comprehensive evaluation system for the quality of Huocao was built. The UPLC fingerprints of 49 batches of Huocao were established, and there were 20 common peaks, of which eight phenolic acids including neochlorogenic acid and chlorogenic acid were identified. Except for three batches of Huocao, the similarity of the other 46 batches was higher than 0.89, suggesting that the established fingerprint method could be used for quality control of the medicinal herb. The correlation coefficient between entropy weight score of the eight phenolic acids and comprehensive fingerprint score in Huocao was 0.875(P<0.01), which indicated that the eight phenolic acids could be used as indicator components for the quality evaluation of Huocao. Furthermore, in multivariate statistical analysis on the common peaks of fingerprint and the contents of the eight phenolic acids, chlorogenic acid, isochlorogenic acid A and isochlorogenic acid C were screened to be the indicator components. The results revealed that the proposed method achieved a simple and accurate quality control of Huocao based on UPLC fingerprint and multi-component content determination, which provided useful data for establishing the quality standard of Huocao.


Assuntos
Ácido Clorogênico , Hidroxibenzoatos , Entropia , Controle de Qualidade
9.
Zhongguo Zhong Yao Za Zhi ; 48(5): 1218-1228, 2023 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-37005806

RESUMO

In this study, ultra-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry(UPLC-Q-TOF-MS) and gas chromatography-mass spectrometry(GC-MS) were combined with non-targeted metabonomic analysis based on multivariate statistics analysis, and the content of five indicative components in nardosinone was determined and compared by UPLC. The main chemical components of Nardostachyos Radix et Rhizoma with imitative wild cultivation and wild Nardostachyos Radix et Rhizoma were comprehensively analyzed. The results of multivariate statistical analysis based on liquid chromatography-mass spectrometry(LC-MS) and GC-MS were consistent. G1 and G2 of the imitative wild cultivation group and G8-G19 of the wild group were clustered into category 1, while G7 of the wild group and G3-G6 of the imitative wild cultivation group were clustered into category 2. After removing the outlier data of G1, G2, and G7, G3-G6 of the imitative wild cultivation group were clustered into one category, and G8-G19 of the wild group were clustered into the other category. Twenty-six chemical components were identified according to the positive and negative ion modes detected by LC-MS. The content of five indicative components(VIP>1.5) was determined using UPLC, revealing that chlorogenic acid, isochlorogenic acid A, isochlorogenic acid C, linarin, nardosinone, and total content in the imitative wild cultivation group were 1.85, 1.52, 1.26, 0.90, 2.93, and 2.56 times those in the wild group, respectively. OPLS-DA based on GC-MS obtained 10 diffe-rential peaks. Among them, the relative content of α-humulene and aristolene in the imitative wild cultivation group were extremely significantly(P<0.01) and significantly(P<0.05) higher than that in the wild group, while the relative content of 7 components such as 5,6-epoxy-3-hydroxy-7-megastigmen-9-one, γ-eudesmol, and juniper camphor and 12-isopropyl-1,5,9-trimethyl-4,8,13-cyclotetrade-catriene-1,3-diol was extremely significantly(P<0.01) and significantly(P<0.05) lower than that in the wild group, respectively. Therefore, the main chemical components of the imitative wild cultivation group and wild group were basically the same. However, the content of non-volatile components in the imitative wild cultivation group was higher than that in the wild group, and the content of some volatile components was opposite. This study provides scientific data for the comprehensive evaluation of the quality of Nardostachyos Radix et Rhizoma with imitative wild cultivation and wild Nardostachyos Radix et Rhizoma.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Gasosa-Espectrometria de Massas , Cromatografia Líquida , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas em Tandem
10.
J Am Chem Soc ; 144(40): 18272-18285, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36173417

RESUMO

Materials with metastable phases can exhibit vastly different properties from their thermodynamically favored counterparts. Methods to synthesize metastable phases without the need for high-temperature or high-pressure conditions would facilitate their widespread use. We report on the electrochemical growth of microcrystals of bismuth selenide, Bi2Se3, in the metastable orthorhombic phase at room temperature in aqueous solution. Rather than direct epitaxy with the growth substrate, the spontaneous formation of a seed layer containing nanocrystals of cubic BiSe enforces the metastable phase. We first used single-crystal silicon substrates with a range of resistivities and different orientations to identify the conditions needed to produce the metastable phase. When the applied potential during electrochemical growth is positive of the reduction potential of Bi3+, an initial, Bi-rich seed layer forms. Electron microscopy imaging and diffraction reveal that the seed layer consists of nanocrystals of cubic BiSe embedded within an amorphous matrix of Bi and Se. Using density functional theory calculations, we show that epitaxial matching between cubic BiSe and orthorhombic Bi2Se3 can help stabilize the metastable orthorhombic phase over the thermodynamically stable rhombohedral phase. The spontaneous formation of the seed layer enables us to grow orthorhombic Bi2Se3 on a variety of substrates including single-crystal silicon with different orientations, polycrystalline fluorine-doped tin oxide, and polycrystalline gold. The ability to stabilize the metastable phase through room-temperature electrodeposition in aqueous solution without requiring a single-crystal substrate broadens the range of applications for this semiconductor in optoelectronic and electrochemical devices.

11.
Nature ; 540(7634): 579-582, 2016 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-27926730

RESUMO

The Yorkie homologues YAP (Yes-associated protein) and TAZ (transcriptional coactivator with PDZ-binding motif, also known as WWTR1), effectors of the Hippo pathway, have been identified as mediators for mechanical stimuli. However, the role of YAP/TAZ in haemodynamics-induced mechanotransduction and pathogenesis of atherosclerosis remains unclear. Here we show that endothelial YAP/TAZ activity is regulated by different patterns of blood flow, and YAP/TAZ inhibition suppresses inflammation and retards atherogenesis. Atheroprone-disturbed flow increases whereas atheroprotective unidirectional shear stress inhibits YAP/TAZ activity. Unidirectional shear stress activates integrin and promotes integrin-Gα13 interaction, leading to RhoA inhibition and YAP phosphorylation and suppression. YAP/TAZ inhibition suppresses JNK signalling and downregulates pro-inflammatory genes expression, thereby reducing monocyte attachment and infiltration. In vivo endothelial-specific YAP overexpression exacerbates, while CRISPR/Cas9-mediated Yap knockdown in endothelium retards, plaque formation in ApoE-/- mice. We also show several existing anti-atherosclerotic agents such as statins inhibit YAP/TAZ transactivation. On the other hand, simvastatin fails to suppress constitutively active YAP/TAZ-induced pro-inflammatory gene expression in endothelial cells, indicating that YAP/TAZ inhibition could contribute to the anti-inflammatory effect of simvastatin. Furthermore, activation of integrin by oral administration of MnCl2 reduces plaque formation. Taken together, our results indicate that integrin-Gα13-RhoA-YAP pathway holds promise as a novel drug target against atherosclerosis.

12.
BMC Med Inform Decis Mak ; 22(1): 9, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35016658

RESUMO

BACKGROUND: This study was designed for the research and development (R&D) and application of a storage inflow and outflow management system enabling departments to perform efficient, scientific, and information-based consumable management. METHODS: In the endocrinology department of a hospital, expert and R&D teams in consumable management were set up, and an information-based storage inflow and outflow management system for consumables was designed and developed. The system was operated on a personal computer and was divided into three modules: public consumables, bed consumables, and quality control management. The functions of the system included storage inflow and outflow, early warnings, response to user queries, and statistics on consumables. Data were derived from the hospital information system (HIS,ZHIY SOFTWARE HIS VERSION4.0) and a questionnaire survey. Economic indicators, work efficiency of consumable management, nurse burnout, consumable stockroom management, and staff satisfaction were compared under manual management, Excel-based management, and the consumable storage inflow and outflow management system. The results of the questionnaire were analysed using the R software, version 4.1.0. RESULTS: Dates were obtained from manual management, Excel-based management and the consumable storage inflow and outflow management system. Under these three methods, the daily prices of department consumables per bed were 53.43 ± 10.27 yuan, 38.65 ± 8.56 yuan, and 31.98 ± 7.36 yuan, respectively, indicating that the new management system reduced costs for the department. The time spent daily on consumable management was shortened from 119.5 (106.75, 123.5) min to 56.5 (48.5, 60.75) to 20 (17.25, 24.25) min. Nurses' emotional fatigue and job indifference scores, respectively, decreased from 22.90 ± 1.65 and 8.75 ± 1.25 under manual management to 19.70 ± 1.72 and 6.90 ± 1.37 under Excel-based management and to 17.20 ± 2.04 and 6.00 ± 1.30 under the novel system; the satisfaction of the warehouse keeper and collection staff, respectively, increased from 76.62% and 80.78% to 91.6% and 90.5% to 98.8% and 98.5% under the three successive systems. CONCLUSIONS: The storage inflow and outflow management system achieved produced good results in the storage and classification of consumables.


Assuntos
Equipamentos Descartáveis , Administração de Materiais no Hospital , Endocrinologia , Departamentos Hospitalares , Sistemas de Informação Hospitalar , Humanos , Inquéritos e Questionários
13.
Zhongguo Zhong Yao Za Zhi ; 47(9): 2480-2490, 2022 May.
Artigo em Chinês | MEDLINE | ID: mdl-35531704

RESUMO

The fingerprint of Boenninghausenia albiflora var. albiflora was established by ultra performance liquid chromatography(UPLC), and the content of 12 active components including chlorogenic acid was determined. Multivariate statistical analysis was used to explore the indicator components of B. albiflora var. albiflora and a comprehensive evaluation system was created for the quality of B. albiflora var. albiflora. In this study, 33 batches of B. albiflora var. albiflora with different sources were collected and studied, and the UPLC fingerprint of B. albiflora var. albiflora was developed. There were 37 common peaks, of which 12 components were identified, and the content of these 12 components was measured. In combination of the common peaks and the content of chemical components, multivariate statistical analysis was performed, and the results showed that 6 components [daphnoretin, isoimperatorin, astragalin, imperatorin, neochlorogenic acid, and isoquercitrin(weight coefficient>0.1)] were selected as chemical markers for the quality of B. albiflora var. albiflora. Technique for order of preference by similarity to ideal solution(TOPSIS) analysis and chemometrics revealed that the quality of S32, S28 and S29 were superior, while that of S12, S7 and S16 were inferior. The quality evaluation method of B. albiflora var. albiflora constructed in this study was accurate and reliable, with simpleness and easiness to operate. It is suggested that the 6 above-mentioned active components could be used as indicator components for quality control of B. albiflora var. al-biflora. The samples were harvested during the flowering and fruiting period, which is from the beginning of July to the end of August.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Medicamentos de Ervas Chinesas/química , Análise Multivariada , Controle de Qualidade
14.
Zhongguo Zhong Yao Za Zhi ; 47(4): 922-930, 2022 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-35285191

RESUMO

The present study explored the kinetics and variation of volatile components of Atractylodis Macrocephalae Rhizoma during the hot-air drying process to obtain the optimal process parameters under multiple goals such as drying efficiency and drying quality. The dry basis moisture content and drying rate curves along with the change of drying time of Atractylodis Macrocephalae Rhizoma were investigated at five levels of drying air temperatures(30, 40, 50, 60, and 70 ℃). The relationship between moisture ratio and time in the drying process of Atractylodis Macrocephalae Rhizoma was fitted and verified by Midilli model, Page model, Overhults model, Modified Page model, Logaritmic model, Two terms Exponential model, and Newton model. Meanwhile, the effective diffusion coefficient of moisture(D_(eff)) and activation energy(E_a) in Atractylodis Macrocephalae Rhizoma were calculated under different drying air temperatures. GC-MS was used to determine the volatile components and content changes of the fresh Atractylodis Macrocephalae Rhizoma and dried products at different temperatures. The dry basis moisture content and drying rate of Atractylodis Macrocephalae Rhizoma were closely related to the temperature of the drying medium, and the moisture of the Atractylodis Macrocephalae Rhizoma decreased with the prolonged drying time. As revealed by the drying rate curve, the drying rate increased with the increase in hot air temperature, and the migration of moisture was accelerated. The comparison of the correlation coefficient(R~2), chi-square(χ~2), and root mean standard error(RMSE) of each model indicated that the parameter average of the Midilli model had the highest degree of fit, with R~2=0.999 2, χ~2=8.78×10~(-5), and RMSE=8.20×10~(-3). Besides, the D_(eff) at 30-70 ℃ was in the range of 1.04×10~(-9)-6.28×10~(-9) m~2·s~(-1), and E_a was 37.47 kJ·mol~(-1). The volatile components of fresh Atractylodis Macrocephalae Rhizoma and dried products at different temperatures were determined by GC-MS, and 18, 18, 18, 17, 17, and 18 compounds were identified respectively, which accounted for more than 84.76% of the volatile components. In conclusion, the hot-air drying of Atractylodis Macrocephalae Rhizoma can be model-fitted and verified and the variation law of the moisture and volatile components of Atractylodis Macrocephalae Rhizoma with temperature is obtained. This study is expected to provide new ideas for exploring the drying characteristics and quality of aromatic Chinese medicine.


Assuntos
Atractylodes , Medicamentos de Ervas Chinesas , Temperatura Alta , Cinética , Rizoma
15.
Acta Pharmacol Sin ; 42(10): 1598-1609, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33495519

RESUMO

Hyperhomocysteinemia (HHcy) is an independent risk factor for cardiovascular diseases and increases mortality in type 2 diabetic patients. HHcy induces endoplasmic reticulum (ER) stress and oxidative stress to impair endothelial function. The glucagon-like peptide 1 (GLP-1) analog exendin-4 attenuates endothelial ER stress, but the detailed vasoprotective mechanism remains elusive. The present study investigated the beneficial effects of exendin-4 against HHcy-induced endothelial dysfunction. Exendin-4 pretreatment reversed homocysteine-induced impairment of endothelium-dependent relaxations in C57BL/6 mouse aortae ex vivo. Four weeks subcutaneous injection of exendin-4 restored the impaired endothelial function in both aortae and mesenteric arteries isolated from mice with diet-induced HHcy. Exendin-4 treatment lowered superoxide anion accumulation in the mouse aortae both ex vivo and in vivo. Exendin-4 decreased the expression of ER stress markers (e.g., ATF4, spliced XBP1, and phosphorylated eIF2α) in human umbilical vein endothelial cells (HUVECs), and this change was reversed by cotreatment with compound C (CC) (AMPK inhibitor). Exendin-4 induced phosphorylation of AMPK and endothelial nitric oxide synthase in HUVECs and arteries. Exendin-4 increased the expression of endoplasmic reticulum oxidoreductase (ERO1α), an important ER chaperone in endothelial cells, and this effect was mediated by AMPK activation. Experiments using siRNA-mediated knockdown or adenoviral overexpression revealed that ERO1α mediated the inhibitory effects of exendin-4 on ER stress and superoxide anion production, thus ameliorating HHcy-induced endothelial dysfunction. The present results demonstrate that exendin-4 reduces HHcy-induced ER stress and improves endothelial function through AMPK-dependent ERO1α upregulation in endothelial cells and arteries. AMPK activation promotes the protein folding machinery in endothelial cells to suppress ER stress.


Assuntos
Estresse do Retículo Endoplasmático/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Exenatida/farmacologia , Homocisteína/efeitos adversos , Dobramento de Proteína/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Chaperonas Moleculares/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo , Espécies Reativas de Oxigênio/metabolismo
16.
BMC Med Inform Decis Mak ; 21(1): 283, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34654419

RESUMO

BACKGROUND: The liver is an important organ that undertakes the metabolic function of the human body. Liver cancer has become one of the cancers with the highest mortality. In clinic, it is an important work to extract the liver region accurately before the diagnosis and treatment of liver lesions. However, manual liver segmentation is a time-consuming and boring process. Not only that, but the segmentation results usually varies from person to person due to different work experience. In order to assist in clinical automatic liver segmentation, this paper proposes a U-shaped network with multi-scale attention mechanism for liver organ segmentation in CT images, which is called MSA-UNet. Our method makes a new design of U-Net encoder, decoder, skip connection, and context transition structure. These structures greatly enhance the feature extraction ability of encoder and the efficiency of decoder to recover spatial location information. We have designed many experiments on publicly available datasets to show the effectiveness of MSA-UNet. Compared with some other advanced segmentation methods, MSA-UNet finally achieved the best segmentation effect, reaching 98.00% dice similarity coefficient (DSC) and 96.08% intersection over union (IOU).


Assuntos
Processamento de Imagem Assistida por Computador , Neoplasias , Humanos , Fígado/diagnóstico por imagem , Tomografia Computadorizada por Raios X
17.
Arterioscler Thromb Vasc Biol ; 39(4): 719-730, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30816805

RESUMO

Objective- TFEB (transcription factor EB) was recently reported to be induced by atheroprotective laminar flow and play an anti-atherosclerotic role by inhibiting inflammation in endothelial cells (ECs). This study aims to investigate whether TFEB regulates endothelial inflammation in diabetic db/db mice and the molecular mechanisms involved. Approach and Results- Endothelial denudation shows that TFEB is mainly expressed in ECs in mouse aortas. Western blotting shows TFEB total protein level decreases whereas the p-TFEB S142 (phosphorylated form of TFEB) increases in db/db mouse aortas, suggesting a decreased TFEB activity. Adenoviral TFEB overexpression reduces endothelial inflammation as evidenced by decreased expression of vascular inflammatory markers in db/db mouse aortas, and reduced expression of a wide range of adhesion molecules and chemokines in human umbilical vein ECs. Monocyte attachment assay shows TFEB suppresses monocyte adhesion to human umbilical vein ECs. RNA sequencing of TFEB-overexpressed human umbilical vein ECs suggested TFEB inhibits NF-κB (nuclear factor-kappa B) signaling. Indeed, luciferase assay shows TFEB suppresses NF-κB transcriptional activity. Mechanistically, TFEB suppresses IKK (IκB kinase) activity to protect IκB-α from degradation, leading to reduced p65 nuclear translocation. Inhibition of IKK by PS-1145 abolished TFEB silencing-induced inflammation in human umbilical vein ECs. Lastly, we identified KLF2 (Krüppel-like factor 2) upregulates TFEB expression and promoter activity. Laminar flow experiment showed that KLF2 is required for TFEB induction by laminar flow and TFEB is an anti-inflammatory effector downstream of laminar flow-KLF2 signaling in ECs. Conclusions- These findings suggest that TFEB exerts anti-inflammatory effects in diabetic mice and such function in ECs is achieved by inhibiting IKK activity and increasing IκBα level to suppress NF-κB activity. KLF2 mediates TFEB upregulation in response to laminar flow.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/fisiologia , Angiopatias Diabéticas/prevenção & controle , Células Endoteliais/metabolismo , Regulação da Expressão Gênica/fisiologia , Quinase I-kappa B/fisiologia , Transdução de Sinais/fisiologia , Fator de Transcrição RelA/fisiologia , Animais , Aorta/metabolismo , Adesão Celular , Diabetes Mellitus Tipo 2/genética , Angiopatias Diabéticas/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação , Fatores de Transcrição Kruppel-Like/fisiologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Condicionamento Físico Animal , Receptores para Leptina/deficiência , Proteínas Recombinantes/metabolismo , Transcrição Gênica
18.
Anal Bioanal Chem ; 412(7): 1483-1495, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31965244

RESUMO

The focus of this study was the analysis of the complex chemical composition from different parts of Buddleja davidii, whose species are commonly known as ornamental plants and herbal medicines in many countries. As an herbal medicine, it has been utilized for stroke treatments, headache, wound healing, neurological disorder, etc. However, the understanding of its chemical matrices is still insufficient. Therefore, an online two-dimensional reversed phase liquid chromatography x hydrophilic interaction liquid chromatography (RPLCxHILIC) system coupled with mass spectrometry was applied for further detailed investigation of the chemical constituents in Buddleja dividii. In this two-dimensional liquid chromatography (2D-LC) method, a new at-column dilution (ACD) modulator was introduced in the 2D-LC system to solve the incompatibility problem of the mobile phase between two dimensions, which resulted in a 2D-LC analysis with high orthogonality. For the root extract, as one of the analyzed samples, the optimization of the 1D and 2D gradients was carried out carefully. With this new modulator, much better peak separation and better peak shape were achieved compared to two-dimensional liquid chromatography system using a traditional standard (TS) modulator. With a similar approach, the other four parts of Buddleja davidii were well separated. Comparing the different analyzed parts, flowers and leaves showed the most complex profiles. MS and MS/MS data were obtained successfully, which demonstrated the potential of the proposed RPLCxHILIC-MS system in the constituents' analysis of herbal medicine. However, due to the lack of reported reference information, 24 compounds could be tentatively identified.


Assuntos
Buddleja/química , Cromatografia de Fase Reversa/métodos , Medicamentos de Ervas Chinesas/química , Interações Hidrofóbicas e Hidrofílicas , Técnicas de Diluição do Indicador , Espectrometria de Massas em Tandem/métodos
19.
Yi Chuan ; 41(7): 599-610, 2019 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-31307969

RESUMO

Variety pedigree contains a lot of information, including parental origin, breeding methods, genetic relationship, and so on. Studying them could reveal the evolution characteristics and rules of breeding and ultimately guide practice. The pedigrees of 326 wheat varieties from 1936 to 2017 in the history of the Sichuan Province was collected and analyzed in terms of breeding methods, parental composition, changes of high frequency parents and backbone parents, genetic contribution, distribution of translocation lines and synthetic germplasms. Over the past 80 years since 1930s, breeders have selected 387 direct parents from a large number of materials, made 256 combinations by means of cross breeding, and have released 314 varieties from them, which contributed directly to wheat breeding and production in Sichuan. Wheat breeding experienced a process from utilizing landraces, introducing foreign germplasm to creating breeding materials independently; high-frequency parents and backbone parents used for breeding gradually changed in different stage of the breeding history. Synthetic germplasms contributed greatly to wheat breeding in recent years. The consistency of breeding objectives will inevitably lead to the loss of genetic diversity and the fragility of genetic basis. In the future, the protection and utilization of genetic resources should be strengthened. In this review, the development of wheat breeding in Sichuan was summarized through pedigree analysis, in order to provide a reference for future research.


Assuntos
Melhoramento Vegetal , Triticum/genética , China , Linhagem
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