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1.
Artigo em Inglês | MEDLINE | ID: mdl-38040523

RESUMO

BACKGROUND: Obesity is a common public health issue and is currently deemed a disease. Research has shown that the risk of gallstones in individuals with obesity is elevated. This study aimed to explore the bile proteomics differences between cholelithiasis patients with obesity and normal body weight. METHODS: Bile samples from 20 patients (10 with obesity and 10 with normal body weight) who underwent laparoscopic cholecystectomy at our center were subjected to tandem mass tag labeling (TMT) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), followed by further bioinformatic analysis. RESULTS: Among the differentially-expressed proteins, 23 were upregulated and 67 were downregulated. Bioinformatic analysis indicated that these differentially-expressed proteins were mainly involved in cell development, inflammatory responses, glycerolipid metabolic processes, and protein activation cascades. In addition, the activity of the peroxisome proliferator-activated receptor (PPAR, a subfamily of nuclear receptors) signaling pathway was decreased in the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Two downregulated proteins in the PPAR signaling pathway, APOA-I and APOA-II, were confirmed using enzyme-linked immunosorbent assay. CONCLUSIONS: The PPAR signaling pathway may play a crucial role in the development of cholelithiasis among patients with obesity. Furthermore, biliary proteomics profiling of gallstones patients with obesity is revealed, providing a reference for future research.

2.
Pharm Biol ; 60(1): 1960-1968, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36205548

RESUMO

CONTEXT: Swertia mussotii Franch. (Gentianaceae) is a source of the traditional Tibetan medicine, ZangYinChen, and is used to treat chronic hepatitis and many types of jaundice. OBJECTIVE: This study explored the therapeutic effects and mechanism of S. mussotii on non-alcoholic fatty liver disease in diet-induced hypercholesterolaemia. MATERIALS AND METHODS: After a week of adaptive feeding, 32 Sprague-Dawley rats were divided into four groups: (1) Control, (2) Control-S, (3) Model, and (4) Model-S. During the 12 experimental weeks, we established the Model using a high-fat diet. Control-S and Model-S were given 1.0 g/kg S. mussotii water extract via gavage starting in the fifth week until the end of experiment. RESULTS: When compared with Model rats, the S. mussotii water extract led to a reduction in high-density lipoproteins (43.9%) and albumin (13.9%) and a decrease in total cholesterol (54.0%), triglyceride (45.6%), low-density lipoproteins (8.6%), aspartate aminotransferase (11.0%), alanine aminotransferase (15.5%), alkaline phosphatase (19.1%), total protein (6.4%), and glucose (20.8%) in serum. A reduction in three cytokines (IL-1ß, IL-6, and TNFα) was detected. Histopathological examination showed that liver steatosis was significantly relieved in S. mussotii-treated high-fat diet rats. S. mussotii also caused a downregulation in the expression of TLR4 (43.2%), MyD88 (33.3%), and a decrease in phosphorylation of NF-κB. DISCUSSION AND CONCLUSIONS: Our findings indicate that S. mussotii may act as a potential anti-inflammation drug via inhibition of the TLR4/MyD88/NF-κB pathway. Further in vivo and in vitro studies are needed to validate its potential in clinical medicine.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Swertia , Alanina Transaminase/metabolismo , Albuminas/metabolismo , Albuminas/farmacologia , Fosfatase Alcalina , Animais , Aspartato Aminotransferases , Colesterol/metabolismo , Dieta Hiperlipídica , Glucose/metabolismo , Interleucina-6/metabolismo , Lipoproteínas HDL/metabolismo , Lipoproteínas HDL/farmacologia , Lipoproteínas LDL/metabolismo , Fígado , Fator 88 de Diferenciação Mieloide , NF-kappa B/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Fosforilação , Ratos , Ratos Sprague-Dawley , Swertia/metabolismo , Receptor 4 Toll-Like/metabolismo , Triglicerídeos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Água/farmacologia
3.
Tohoku J Exp Med ; 254(1): 17-23, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34011804

RESUMO

Tripartite motif-containing 44 (TRIM44) was reported to be involved in the tumorigenesis of several tumors, but its function in laryngeal squamous cell carcinoma has not been investigated yet. In the present study, we aimed to elucidate the function of TRIM44 in laryngeal squamous cell carcinoma, and identify the compounds which could inhibit TRIM44 expression. Our results showed that TRIM44 was upregulated in tumor tissues and cell lines of laryngeal squamous cell carcinoma. Knockdown of TRIM44 significantly inhibited cell growth of laryngeal squamous cell carcinoma by suppressing TLR4, phosphorylated AKT and phosphorylated NF-κB p65 expression in vitro. Moreover, TRIM44 knockdown inhibited tumor growth in nude mice, which further suggested that TRIM44 exerted oncogenic activity in laryngeal squamous cell carcinoma. Interestingly, it was found that nuciferine significantly inhibited the mRNA levels of TRIM44 after screening a small natural compound library. Our further studies showed nuciferine markedly downregulated the protein levels of TRIM44 and its substrate TLR4 in a concentration-dependent manner in laryngeal squamous cell carcinoma cells. Moreover, the activation of downstream kinases of TLR4 such as AKT signaling pathway was also inhibited by nuciferine. Additionally, nuciferine markedly inhibited cell survival of laryngeal squamous cell carcinoma in a concentration-dependent manner. In contrast, TRIM44 overexpression significantly reduced the cytotoxicity of nuciferine in laryngeal squamous cell carcinoma cells. In conclusion, this study indicated that inhibiting TRIM44 would be a useful strategy for the treatment of laryngeal squamous cell carcinoma, and nuciferine could be a potential chemical applicated in the therapy of laryngeal squamous cell carcinoma.


Assuntos
Aporfinas , Neoplasias de Cabeça e Pescoço , Peptídeos e Proteínas de Sinalização Intracelular , Animais , Carcinogênese , Proteínas de Transporte , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas c-akt/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Receptor 4 Toll-Like , Proteínas com Motivo Tripartido/metabolismo
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2036-41, 2016 Jul.
Artigo em Zh | MEDLINE | ID: mdl-30035872

RESUMO

In this research, the terahertz spectra data of the aging wheat processed under manual control environment by ATR accessory were collected. After the data diversity based on the composite score by PCA, the non-destructive identification models of aging wheat were developed by PLS-DA algorithm. The results showed that for the absorption coefficient spectrum, the accuracy of the experimental group, control group of the calibration set and cross validation set were 84.2%, 94.7%, 84.2% and 81.6% respectively, while the accuracy of the experimental group and control group of the external validation set were 73.7% and 100.0% respectively; for the refractive index spectrum, the accuracy of the experimental group, control group of the calibration set and cross validation set were 84.2%, 92.0%, 76.3% and 76.3% respectively, while the accuracy of the experimental group and control group of the external validation set were 84.2% and 89.5% respectively. The research indicates that ATR-THz technology should be of great potentials in the application in the non-destructive identification of aging wheat.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(11): 2938-43, 2014 Nov.
Artigo em Zh | MEDLINE | ID: mdl-25752035

RESUMO

In the present paper, the micro-NIR spectrometer with the splitter of linear variable filter was used to develop the recognition models of the West Lake Longjing tea and the ordinary flat tea of the year 2012 and 2013. The NIR spectral data of different years and different storage times were decomposed by PCA algorithm. The PLS-DA models were developed by the representative samples selected by the mathematical characteristics of PCA-scores' distribution in order to analyze the reason for the inadaptability of the models according to mathematical principles and find out the solution for its correction. Being examined by the external validation set, the adaptability of the authenticity identification model was enhanced effectively. The result of this research indicated that, for the West Lake Longjing tea and the ordinary flat tea, the correct recognition rate of the model developed by all different-year samples' NIR spectral data would be enhanced effectively. The model developed by the NIR spectral data of different storage time samples indicated that the physicochemical properties of the ordinary flat tea have changed remarkably after cryopreservation for 3 months, while the physicochemical properties of the West Lake Longjing tea are relatively stable. The model adaptabilities for different years and different storage times were studied according to the mathematical perspective of the principal component characteristics of spectral data. After the authenticity identification model of West Lake Longjing tea was developed, the prediction accuracy was enhanced effectively. This research would provide reference for not only the application of NIR spectroscopy in quality grading and safety of agricultural products, but also the enhancement of the prediction accuracy of the NIR grading models for agricultural products.


Assuntos
Análise de Alimentos/métodos , Chá/classificação , Algoritmos , Modelos Teóricos , Espectroscopia de Luz Próxima ao Infravermelho
6.
Clin Exp Pharmacol Physiol ; 40(7): 449-57, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23662699

RESUMO

Chronic intermittent hypoxia (CIH) contributes to the development of cardiovascular diseases in patients with obstructive sleep apnoea. Many studies have shown an association between increased circulating endothelin (ET)-1 levels and CIH. The aim of the present study was to determine the role of ET receptors in altered aortic function in an animal model of CIH. Rats were subjected to CIH (Fi o2 9% for 1 min, repeated every 2 min for 8 h/day, 7 days/week) for 3 weeks. After 3 weeks, the rats were killed and their aortas retrieved for use in in vitro experiments (isometric force measurement), histological analysis, immunohistochemistry and western blotting. Aortas from rats subjected to CIH exhibited marked endothelial dysfunction and increased responsiveness to ET-1. Furthermore, CIH induced increased ET-1 and ETA receptor expression, whereas ETB receptor expression was decreased. Aortic contractile responses to ET-1 were inhibited by the ETA and ETB receptor antagonists BQ-123 and BQ-788, respectively. Acetylcholine-induced relaxation responses were significantly attenuated in aortas from rats subjected to CIH, whereas CIH had no significant effect on aortic responses to sodium nitroprusside. The results of the present study suggest that increased expression of ETA receptors, which mediate a potent vasoconstrictor response, plays an important role in the pathogenesis of CIH. In addition, decreased endothelial ETB receptor expression, which is associated with the functional decline of endothelium-dependent vasodilation, also contributes to the pathogenesis of CIH. It appears that the ETB receptor-induced buffering of ET-1 responsiveness is mediated via a nitric oxide-dependent mechanism.


Assuntos
Endotelina-1/metabolismo , Hipóxia/fisiopatologia , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/metabolismo , Vasoconstrição/fisiologia , Animais , Aorta/metabolismo , Aorta/fisiopatologia , Modelos Animais de Doenças , Antagonistas do Receptor de Endotelina A , Antagonistas do Receptor de Endotelina B , Endotelina-1/genética , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Hipóxia/genética , Hipóxia/metabolismo , Masculino , Óxido Nítrico/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor de Endotelina A/genética , Receptor de Endotelina B/genética , Vasoconstrição/genética , Vasodilatação/genética , Vasodilatação/fisiologia
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 69-73, 2013 Jan.
Artigo em Zh | MEDLINE | ID: mdl-23586227

RESUMO

The safety of wheat flour is always focused by all quarters of society. Based on comparing the feature of NIR spectra of calcium oxide, calcium hydroxide and calcium carbonate in this research, the diffuse reflection NIR spectra of the wheat flour samples with different content of calcium oxide, calcium hydroxide and calcium carbonate mixed in were collected. The calibration models of lime and calcium carbonate were developed by partial least square algorithm, with the validation method of cross validation. The result indicated that the determination coefficients (R2) of lime and calcium carbonate are 99.80% and 96.98% respectively, the root mean square errors of calibration set are 0.19 and 0.34 respectively; the root mean square errors of cross validation set are 0.26 and 0.75 respectively; the root mean square errors of prediction set are 0.63 and 0.44 respectively; the ratio performance deviations (RPD) are 8.57 and 5.24 respectively, which indicated that the calibration models were precise enough to adapt to the on-site rapid determination of lime in wheat flour. The result of F-test indicated that a very remarkable correlation exists between the estimated and specified values of the calibration sets and the external validation sets. This research, to some extent, will provide some reference methods for the rapid determination of wheat flour for quality safety, which is important for the quality control of wheat flour.


Assuntos
Compostos de Cálcio/análise , Farinha/análise , Contaminação de Alimentos/análise , Óxidos/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Calibragem , Análise dos Mínimos Quadrados , Reprodutibilidade dos Testes
8.
Se Pu ; 41(6): 527-534, 2023 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-37259878

RESUMO

Halogenated polycyclic aromatic hydrocarbons (H-PAHs), including chlorinated polycyclic aromatic hydrocarbons (Cl-PAHs) and brominated polycyclic aromatic hydrocarbons (Br-PAHs), are compounds in which one or more hydrogen atoms replaced by chlorine or bromine atoms. These compounds are not only difficult to degrade but also highly fat soluble and toxic. They are a new type of high-risk organic pollutants with structures similar to those of dioxins, and their toxicity is even higher than that of the parent polycyclic aromatic hydrocarbons (PAHs). The bioaccumulation of H-PAHs can be predicted by their octanol-water partition coefficient (Kow); in general, higher bioaccumulation capacity and Kow values indicate greater fat solubility. Therefore, animal-derived foods with higher fat contents, such as animal meat, milk, aquatic products, and their processed forms, are more likely to be contaminated with higher contents of H-PAHs than those with lower fat contents. In this work, a gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) method coupled with stable isotope dilution was established to determine 15 H-PAHs in aquatic products. The instrument and pretreatment methods were systematically optimized. The GC-MS/MS used in this method can effectively eliminate matrix interferences and features high sensitivity and low analytical cost; thus, it has good application prospects. The samples were added with an isotope internal standard before extraction to calibrate the loss of the tested substance during the pretreatment process, extracted by accelerated solvent extraction, purified using gel permeation chromatography and PRiME HLB columns, and then analyzed by GC-MS/MS. The use of two DB-5MS chromatographic columns (30 m×0.25 mm×0.25 µm) and microplate fluidics technology to connect chromatographic columns 1 and 2 in series led to better separation effects, good peak shapes, and high target compound responses. The 15 H-PAHs demonstrated good linearities in the range of 1-50 µg/L, with correlation coefficients (r) greater than or equal to 0.993. The relative standard deviation (RSD) values of the relative response factor (RRF) of the H-PAHs were less than 9%, the method detection limit (MDL) was 0.009-0.072 µg/kg, and the method quantification limit (MQL) was 0.031-0.240 µg/kg. Three spiked levels of 0.25, 1.0, 2.5 µg/kg were added to the blank samples to determine the recovery and precision. The recoveries for these spiked levels were 74.6%-116.8%, 77.8%-123.2%, and 71.9%-124.8%, respectively, and the corresponding RSDs were 0.6%-8.2%, 0.6%-9.0%, and 0.4%-10.6%, respectively. The total actual content of H-PAHs in aquatic product samples was 0.60-3.54 µg/kg. Among the H-PAHs investigated, 9-chlorophenanthrene (9-ClPhe) showed the greatest detection rate (100%) and highest content (1.15 µg/kg), indicating that H-PAHs widely exist in aquatic products. Thus, further assessment of the dietary exposure risk of these compounds is necessary. The developed method simplifies the pretreatment step, and has the advantages of simplicity, rapid analysis, high recoveries, and good stability. It is suitable for the qualitative and quantitative analysis of H-PAHs in actual aquatic product samples and provides reliable technical support for the residue status and risk assessment of H-PAHs in aquatic products.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Animais , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Ambientais/análise , Isótopos
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(3): 826-9, 2012 Mar.
Artigo em Zh | MEDLINE | ID: mdl-22582662

RESUMO

The concentrations of main heavy metal pollutants (Cu, Zn, Pb, Cr and As) in soil were tested by NITON XL3 600 portable X-ray fluorescence spectrometry (PXRF). The results showed that the minimum? detection limits for elements Cu, Zn, Pb, Cr and As were 23.96, 11.69, 8.58, 19.23, 6.24 mg x kg(-1), respectively. The soil composition standard material GSS-5 was detected by PXRF for 5 replicate measurements, The accuracy was 96%-102% and relative standard deviations (RSD) was 1.0%-7.6%. In term of field situ testing, RSD was less than 20%, and accuracy was 55%-119%. The performance was assessed by laboratory testing and field situ detection, and the results indicated that PXRF is effective for rapid, quantitative monitoring of soil metal contamination.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(8): 2223-7, 2012 Aug.
Artigo em Zh | MEDLINE | ID: mdl-23156786

RESUMO

Offner imaging spectrometer is a kind of pushbroom imaging system. Hyperspectral images acquired by Offner imaging spectrometers require relative motion of sensor and scene that is translation or rotation. Via rotating scan with a reflector at the front of sensor's len, large objects can be entirely captured. But for the changes in object distances, geometric distortion occurs. A formula of space projection from an object point to an image point by one capture was derived. According to the projection relation and slit's motion curve, the object points' coordinates on a reference plan were obtained with rotation angle for a variable. A rotating scan device using a reflector was designed and installed on an Offner imaging spectrometer. Clear images were achieved from the processing of correction algorithm.

11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(3): 589-94, 2011 Mar.
Artigo em Zh | MEDLINE | ID: mdl-21595197

RESUMO

Labor intensive, time consuming, high technical requirements in operation and much affected by human factors is the limitation of diagnosing the crop information with conventional method, which could not make diagnosis real-time and rapid. Imaging spectral technique could simultaneously obtain the image and spectral information of crops. It could diagnose the growth and insects information of crop rapidly and non-destructively. In recent years, imaging spectroscopy has been widely used in diagnosis of the information of crop, so it provides technical support for agricultural informatization. In the present study, the principle of imaging spectroscopy was presented. The application progress of imaging spectroscopy technique in crop detection was investigated, including seed component detection, seed variety discrimination, seed disease and insect pest detection, field crop growth monitoring and field crop disease and insects monitoring. Then the paper analyzed difficulty of imaging spectroscopy for crop measurement, and the prospect of this technique was also discussed.


Assuntos
Produtos Agrícolas , Análise Espectral/métodos , Agricultura/métodos
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(9): 2313-8, 2011 Sep.
Artigo em Zh | MEDLINE | ID: mdl-22097817

RESUMO

FTIR microspectroscopy technique was born in the mid-nineties. The research on this technique has just began abroad, and this technology has not yet been widely recognized in China. It is a rapid, nondestructive testing technology, has the advantages of microdomain, visualization, high precision and high sensitivity. In the present study, the composition, operational principle and working mode of FTIR microspectroscopy were summarized. The progress in application of FTIR microspectroscopy technique was investigated in some fields, including biomedicine, microbiology, forensic science, materials science, nutrition and feed science and agricultural products. The difficulty of FTIR microspectroscopy research and the prospects of this technique were also discussed.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(9): 2377-82, 2011 Sep.
Artigo em Zh | MEDLINE | ID: mdl-22097830

RESUMO

The NIR/MIR micro-imaging can supply not only the information of spectra, but also the information of spacial distribution of the sample, which is superior to the traditional NIR/MIR spectroscopy analysis. In the present paper, polyethylene and parafilm, with similar appearances, were regarded as the research objects, of which the NIR/MIR micro-imaging was collected. Chemical imaging (CI) and compare correlation imaging were carried out for the two materials respectively to discuss the imaging methods of the two materials. The result indicated that the differentiation of the CI values of the two materials in the NIR/MIR CI for material II was 0.004 8 and 0.254 8 respectively, while those in the NIR/MIR CI for material I were 0.002 6 and 0.326 5, respectively. Clear CI was acquired, and the two materials could be differentiated. The result of the compare correlation imagings indicated that the compare correlation imagings, in which the NIR/MIR spectra of the two materials were regarded as reference spectra respectively, can differentiate the two materials remarkably with clear imagings. In the compare correlation imagings of MIR micro-imaging, the difference of the correlation coefficients between the two materials' MIR spectra and the reference spectrum was more than 0.12, which showed a better imaging result; while a tiny difference of the correlation coefficients between the two materials' NIR spectra and the reference spectrum could be employed to show a clear imaging result for NIR compare correlation imaging so as to differentiate the two materials. This thesis, to some extent, can supply the reference to not only the rapid discrimination of the safety of the packaging material for agri-food, but also the imaging methods for NIR/MIR micro-imaging to differentiate the different materials.

14.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 9): m1026, 2009 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-21577393

RESUMO

In the title compound, [Mg(C(12)H(8)N(2))(2)(H(2)O)(2)][Cr(2)O(7)]·2C(12)H(8)N(2), the cation and anion are situated on a twofold rotation axis. The Mg(II) ion is coordinated by four N atoms from two 1,10-phenanthroline ligands and two O atoms from coordinated water mol-ecules in a distorted octa-hedral geometry. Inter-molecular O-H⋯N and O-H⋯O hydrogen bonds and π-π inter-actions between the aromatic rings [shortest centroid-centroid separation = 3.527 (2) Å] link the cations, anions and 1,10-phenanthroline solvent mol-ecules into a hydrogen-bonded cluster.

15.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): m894, 2009 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-21583356

RESUMO

The title compound, [Ru(2)(C(13)H(15)S)(2)(CO)(4)], is a centrosymmetric binuclear metal-carbonyl complex containing an Ru-Ru single bond [2.7511 (8) Å]. Each Ru(I) atom is coordinated by two bridging carbonyl ligands, one terminal carbonyl ligand and one η(5)-cyclo-penta-dienyl group. The complex has a trans conformation and the two cyclo-penta-dienyl ring planes are parallel. The crystal structure involves weak C-H⋯O hydrogen bonds.

16.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 8): m895, 2009 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-21583357

RESUMO

In the crystal structure of the title compound, [Ru(2)(C(14)H(17)O)(2)(CO)(4)], each Ru(I) atom is connected to one end-on and two bridging carbonyl groups and one cyclo-penta-dienyl ring. The two Ru atoms are connected into binuclear complexes via two bridging carbonyl groups, forming four-membered rings which are located on centres of inversion. The Ru-Ru distance of 2.7483 (11) Šcorresponds to a single bond. The two carbonyl groups in these binuclear complexes are trans-oriented.

17.
World J Gastroenterol ; 14(40): 6249-53, 2008 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-18985819

RESUMO

AIM: To investigate the ultrastructural location of midkine (MK) in nucleolus and function corresponding to its location. METHODS: To investigate the ultrastructural location of MK in nucleolus with immunoelectronic microscopy. To study the role that MK plays in ribosomal biogenesis by real-time PCR. The effect of MK on anti-apoptotic activity of HepG2 cells was studied with FITC-conjugated annexin V and propidium iodide PI double staining through FACS assay. RESULTS: MK mainly localized in the granular component (GC), dense fibrillar component (DFC) and the border between the DFC and fibrillar center (FC). The production of 45S precursor rRNA level was decreased significantly in the presence of MK antisense oligonucleotide in the HepG2 cells. Furthermore, it was found that exogenous MK could protect HepG2 from apoptosis significantly. CONCLUSION: MK was constitutively translocated to the nucleolus of HepG2 cells, where it accumulated and mostly distributed at DFC, GC components and at the region between FC and DFC, MK played an important role in rRNA transcription, ribosome biogenesis, and cell proliferation in HepG2 cells. MK might serve as a molecular target for therapeutic intervention of human carcinomas.


Assuntos
Carcinoma Hepatocelular/metabolismo , Nucléolo Celular/metabolismo , Neoplasias Hepáticas/metabolismo , Fatores de Crescimento Neural/metabolismo , RNA Ribossômico/metabolismo , Transcrição Gênica , Transporte Ativo do Núcleo Celular , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/ultraestrutura , Linhagem Celular Tumoral , Nucléolo Celular/ultraestrutura , Proliferação de Células , Separação Celular , Citometria de Fluxo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/ultraestrutura , Microscopia Imunoeletrônica , Midkina , Fatores de Crescimento Neural/genética , Oligonucleotídeos Antissenso/metabolismo , Reação em Cadeia da Polimerase
18.
Int J Oncol ; 52(5): 1651-1660, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29568945

RESUMO

Pancreatic cancer is one of the most lethal types of cancer; owing to low early detection rates and high metastasis rates, it is associated with an extremely poor prognosis. Therefore, a better understanding of the molecular mechanisms that underlie its metastasis and the identification of potential prognostic biomarkers are urgently required. Although high expression levels of asparaginyl endopeptidase (AEP) have been detected in various types of solid tumor, the expression and functions of AEP in pancreatic carcinomas have yet to be determined. The present study aimed to examine the putative functions of AEP in pancreatic carcinoma. Immunohistochemical analysis revealed that AEP was highly expressed in pancreatic cancer tissues compared with adjacent normal tissues. Patients with high AEP expression exhibited a significantly shorter overall survival time. Results from multivariate Cox regression analysis revealed that AEP was an independent prognostic factor for overall survival. Gain- and loss-of-function experiments demonstrated that knockdown of AEP expression significantly reduced the invasive ability of pancreatic cancer cells, whereas overexpression of AEP increased the invasive ability. In addition, AEP was detected in exosomes that were derived from cultured pancreatic ductal adenocarcinoma cells (PDACs) and in the serum from patients with PDAC. The Matrigel-Transwell invasion assay revealed that exosomes enriched with AEP were able to enhance the invasive ability of PDAC cells, whereas exosomes lacking AEP decreased the invasive ability. Furthermore, results from the present study suggested that AEP may be crucial for activation of the phosphoinositide 3-kinase/RAC­α serine/threonine-protein kinase signaling pathway in PDAC cells. The present study data indicated that high AEP expression may be important for pancreatic carcinoma progression in an exosome-dependent manner, and that AEP may be an independent indicator of poor prognosis in patients with PDAC and may be a novel prognostic biomarker or therapeutic target in pancreatic carcinoma.

19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(7): 1319-22, 2007 Jul.
Artigo em Zh | MEDLINE | ID: mdl-17944404

RESUMO

With the widespread application of remote sensing (RS) in agriculture, monitoring and prediction of crop nutrition condition attracts attention of many scientists. Foliar nitrogen content (N) is one of the most important nutrients for plant growth, and vertical leaf N gradient is an important indicator of crop nutrition situation. Investigations have been made on N vertical distribution to describe the growth status of winter wheat. Results indicate that from the canopy top to the ground surface, N shows an obvious gradient decreasing trend. The objective of this study was to discuss the inversion method of N vertical distribution with canopy reflected spectrum by the partial least squares regression (PLS) method. PLS was selected for the inversion of upper, middle and lower layers of N. To improve the accuracy of prediction, the N in the upper layer as well as in the middle and bottom layers should be taken into consideration when crop nutrition condition is appraised by RS data. The established models by the observed data in year 2001-2002 were validated by the data in year 2003-2004. The inversion precision and error were acceptable. It provided a theoretic basis for widely and non-damaged variable rate nitrogen application of winter wheat by canopy reflected spectrum.


Assuntos
Análise dos Mínimos Quadrados , Nitrogênio/análise , Folhas de Planta/química , Espectrofotometria/métodos , Triticum/química , Agricultura/métodos , Nitrogênio/metabolismo , Folhas de Planta/metabolismo , Análise de Regressão , Reprodutibilidade dos Testes , Estações do Ano , Triticum/metabolismo
20.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 31(6): 567-71, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27215026

RESUMO

OBJECTIVE: To study the impacts of exposure to electromagnetic radiation (EMR) on liver function in rats. METHODS: Twenty adult male Sprague-Dawley rats were randomly divided into normal group and radiated group. The rats in normal group were not radiated, those in radiated group were exposed to EMR 4 h/ d for 18 consecutive days. Rats were sacrificed immediately after the end of the experiment. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and those of malondialdehyde (MDA) and glutathione (GSH) in liver tissue were evaluated by colorimetric method. The liver histopathological changes were observed by hematoxylin and eosin staining and the protein expression of bax and bcl- 2 in liver tissue were detected by immunohistochemical method. Terminal-deoxynucleotidyl transferase mediated nick and labelling (TUNEL) method was used for analysis of apoptosis in liver. RESULTS: Compared with the normal rats, the serum levels of ALT and AST in the radiated group had no obvious changes (P>0.05), while the contents of MDA increased (P < 0.01) and those of GSH decreased (P < 0.01) in liver tissues. The histopathology examination showed diffuse hepatocyte swelling and vacuolation, small pieces and focal necrosis. The immunohistochemical results displayed that the expression of the bax protein was higher and that of bcl-2 protein was lower in radiated group. The hepatocyte apoptosis rates in radiated group was higher than that in normal group (all P < 0.01). CONCLUSION: The exposure to 900 MHz mobile phone 4 h/d for 18 days could induce the liver histological changes, which may be partly due to the apoptosis and oxidative stress induced in liver tissue by electromagnetic radiation.


Assuntos
Telefone Celular , Radiação Eletromagnética , Fígado/patologia , Fígado/efeitos da radiação , Animais , Apoptose , Masculino , Estresse Oxidativo , Proteômica , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem
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