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1.
Front Chem ; 10: 940184, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36212067

RESUMO

Microcapsule self-healing technology is an effective scheme to improve the durability of cementitious composites. In this paper, the compressive properties of microcapsule-based self-healing cementitious composites after freeze-thaw cycles were studied using acoustic emission (AE), and the changes in AE characteristics, compressive strength, mass loss rate, and electric flux of microcapsule-based self-healing cementitious composites with different microcapsule contents and freeze-thaw cycles were studied. The results show that if the content of the microcapsule is appropriate, with the increase in the number of freeze-thaw cycles, the AE hits will generally increase first and then decrease, and the early AE events will also decrease. Because of the different contents of microcapsules, the improvement effect and defect effect change dynamically with the number of freeze-thaw cycles, which is also reflected in the dynamic process of compressive strength. After 100 freeze-thaw cycles, the compressive strength of self-healing cementitious composite samples with 5% content of microcapsules and 3% content of microcapsules is the highest. The changes in mass loss rate and electric flux are similar to the AE characteristic parameters, which further verifies the results of AE. The research results of this paper provide experimental data and experimental methods for the engineering application of microcapsule self-healing cement-based composites in cold areas.

2.
Materials (Basel) ; 14(17)2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34500957

RESUMO

Self-healing concrete designs can protect against deterioration and improve durability. However, there is no unified conclusion regarding the effective preparation and mechanical properties of self-healing concrete. In this paper, microcapsules are used in cement-based materials, the reasonable dosage of microcapsules is determined, and the self-healing performance of the microcapsule self-healing system under different curing agents is explored. The microcapsules and curing agent are shown to enhance the flexural and compressive strength of mortar specimens at relatively low contents. The optimal microcapsule content in terms of compressive strength is 1-3%. When the content of the microcapsule reaches 7%, the strength of the specimen decreases by approximately 30%. Sodium fluorosilicate is better-suited to the microcapsule self-healing cement-based system than the other two fluorosilicates, potassium fluorosilicate and magnesium, which have similarly poor healing performance as curing agents. Healing time also appears to significantly influence the microcapsule self-healing system; mortar specimens that healed for 28 days are significantly higher than those that healed for 7 days. This work may provide a valuable reference for the design and preparation of self-healing cementitious composite structures.

3.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 34(2): 130-133, 2018 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-29926676

RESUMO

OBJECTIVES: To investigate the effect of two kinds of fermented food, noni juice and natto, on blood glucose and lipids in induced diabetic mice. METHODS: Female (ICR) mice were induced into diabetes by an injection of alloxan (55 mg/kg, i. v.). After 72 hours, those mice whose fasting blood glucose levels were over 12.00 mmol/L and urine sugar was strongly positive (+ + +) were regarded as diabetical model and were randomly divided into three groups (n=10):diabetical model (DM) group, noni juice (NJ) group and natto (NT) group. Another ten normal female ICR mice were taken as normal control (NC) group. The mice in NJ and NT groups were gavaged with noni juice (25.0 ml/kg) and natto (0.6 g/kg) respectively. The other two groups were given normal saline (25.0 ml/kg). Continuous gavage administration was given for 30 days, the water-drinking volume and food-intake were recorded. After 1.5 h of the last administration, the glucose tolerance of mice was measured. Finally, the changes in glycated serum protein(GSP), insulin(Ins) and blood lipids of blood samples of mice, taken from the femoral artery, were determined. RESULTS: Compared to the NC group, the water-drinking amount and food-intake, GSP and total cholesterol (TC), triglyceride(TG) and low density lipoprotein (LDL) in DM group were increased significantly (P<0.01), while glucose tolerance, Ins and high density lipoprotein (HDL) were decreased significantly (P<0.01). However, when it came to DM group, NJ and NT could significantly (P<0.01 or P<0.05) reduce, GSP, TG and LDL, meanwhile improve glucose tolerance, Ins and HDL (P<0. 01). CONCLUSIONS: Both noni juice and natto could reduce the blood glucose levels in induced diabetical mice and improve blood lipids, which suggested that they may have certain application value in prevention and treatment of diabetic mellitus.


Assuntos
Glicemia , Diabetes Mellitus Experimental/sangue , Alimentos Fermentados , Lipídeos/sangue , Animais , Feminino , Sucos de Frutas e Vegetais , Camundongos , Camundongos Endogâmicos ICR , Distribuição Aleatória
4.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 34(2): 173-176, 2018 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-29926685

RESUMO

OBJECTIVES: To investigate the effects of saffron aqueous extract (SE) on blood glucose, lipid and pancreatic tissue in streptozocin-induced diabetes mice. METHODS: Diabetes mellitus mice were established by intraperitoneal injection of streptozocin (60 mg/kg) for two consecutive days. The 30 well-established diabetes mice were randomly divided into three groups(n=10):diabetic mellitus (DM) group, SE treated (SE) group and positive control (metformin hydrochloride, MH) group. Another ten normal mice were selected as normal control (NC) group. The mice in SE and MH groups were intragastrically administered with SE 100 mg/kg or MH 100 mg/kg once a day for 6 weeks, mice in DM and NC were given normal saline. The amount of food-intake, water consumption and body weight were measured weekly, the changes of the indicators including fasting blood glucose (FBG), oral glucose-tolerance test (OGTT), glycated serum protein (GSP), insulin (INS) and blood lipid were determined after 6 weeks of continuous administration. The pathologic changes in the pancreas tissues were detected by HE staining. RESULTS: Compared with the normal control group, the amount of food-intake, water consumption, area under the curve, FBG, GSP, and total cholesterol (TC) were significantly increased, while fasting weight, INS and high density lipoprotein cholesterol (HDL-c) were dramatically decreased in DM group. Compared with DM group, the water consumption, FBG, area under the curve and TC in SE group were starkly declined with a notable elevation of HDL-c and INS. In addition, the biopsy from DM mice showed the structure of pancreas islet was destroyed and reduced, and vascular proliferation with irregular shape. The damaged pancreas was obviously repaired by giving SE. CONCLUSIONS: The saffron aqueous extract had efficacy on blood glucose and blood lipids reduction, improvement on damaged pancreas in streptozocininduced diabetic mice, which suggested that saffron could be used for the treatment in diabetes.


Assuntos
Glicemia , Crocus/química , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Extratos Vegetais/farmacologia , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Insulina/sangue , Camundongos , Distribuição Aleatória , Estreptozocina
5.
Breast Cancer Res Treat ; 170(2): 321-328, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29564742

RESUMO

PURPOSE: While HER2 testing is well established in directing appropriate treatment for breast cancer, a small percentage of cases show equivocal results by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Alternative probes may be used in equivocal cases. We present a single community-based institution's experience in further evaluating these cases. PATIENTS AND METHODS: Between 2014 and 2016, 4255 samples were submitted for HER2 amplification testing by alternative probes, TP53, RAI1, and RARA. Of the patients tested by FISH, 505/3908 (12.9%) also had IHC data. RESULTS: Most (73.9%) FISH equivocal cases remained equivocal after IHC testing. However, 50.5% of equivocal cases were classified as HER2 amplified by alternative probes. Most cases were positive by more than one probe: 78% of positive cases by RAI1 and 73.9% by TP53. There was a significant difference between IHC and FISH alternative testing (p < 0.0001) among the equivocal cases by conventional FISH testing, 44% of IHC negative cases became positive while 36% of the positive IHC cases became negative by alternative FISH testing. Available data showed that 41% of patients were treated with palbociclib and were positive by alternative FISH. CONCLUSION: The prevalence of double HER2 equivocal cases and the discrepancy between IHC and alternative FISH testing suggest that FISH alternative testing using both RAI1 and TP53 probes is necessary for conclusive classification. Because almost half of FISH equivocal cases converted to HER2 amplified upon alternative testing, clinical studies to determine the benefit of anti-HER2 therapy in these patients are urgently needed.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Neoplasias da Mama/patologia , Feminino , Amplificação de Genes , Humanos , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
6.
Pharmacogn Mag ; 14(53): 70-75, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29576704

RESUMO

BACKGROUND: Noni juice has been extensively used as folk medicine for the treatment of arthritis, infections, analgesic, colds, cancers, and diabetes by Polynesians for many years. Due to the lack of standard scientific evaluation methods, various kinds of commercial Noni juice with different quality and price were available on the market. OBJECTIVE: To establish a sensitive, reliable, and accurate high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry (HPLC-ESI-MS/MS) method for separation, identification, and simultaneous quantitative analysis of bioactive constituents in Noni juice. MATERIALS AND METHODS: The analytes and eight batches of commercially available samples from different origins were separated and analyzed by the HPLC-ESI-MS/MS method on an Agilent ZORBAX SB-C18 (150 mm × 4.6 mm i.d., 5 µm) column using a gradient elution of acetonitrile-methanol-0.05% glacial acetic acid in water (v/v) at a constant flow rate of 0.5 mL/min. RESULTS: Seven components were identification and all of the assay parameters were within the required limits. Components were within the correlation coefficient values (R2 ≥ 0.9993) at the concentration ranges tested. The precision of the assay method was <0.91% and the repeatability between 1.36% and 3.31%. The accuracy varied from 96.40% to 103.02% and the relative standard deviations of stability were <3.91%. Samples from the same origin showed similar content while different origins showed significant different result. CONCLUSIONS: The developed methods would provide a reliable basis and be useful in the establishment of a rational quality control standard of Noni juice. SUMMARY: Separation, identification, and simultaneous quantitative analysis method of seven bioactive constituents in Noni juice is originally developed by high-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometryThe presented method was successfully applied to the quality control of eight batches of commercially available samples of Noni juiceThis method is simple, sensitive, reliable, accurate, and efficient method with strong specificity, good precision, and high recovery rate and provides a reliable basis for quality control of Noni juice. Abbreviations used: HPLC-ESI-MS/MS: High-performance liquid chromatography with electrospray ionization triple quadrupole mass spectrometry, LOD: Limit of detection, LOQ: Limit of quantitation, S/N: Signal-to-noise ratio, RSD: Relative standard deviations, DP: Declustering potential, CE: Collision energy, MRM: Multiple reaction monitoring, RT: Retention time.

7.
Oncotarget ; 9(17): 13682-13693, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29568386

RESUMO

BACKGROUND: The role of MET amplification in lung cancer, particularly in relation to checkpoint inhibition and EGFR WT, has not been fully explored. In this study, we correlated PD-L1 expression with MET amplification and EGFR, KRAS, or TP53 mutation in primary lung cancer. METHODS: In this retrospective study, tissue collected from 471 various tumors, including 397 lung cancers, was tested for MET amplification by FISH with a MET/centromere probe. PD-L1 expression was evaluated using clone SP142 and standard immunohistochemistry, and TP53, KRAS, and EGFR mutations were tested using next generation sequencing. RESULTS: Our results revealed that PD-L1 expression in non-small cell lung cancer is inversely correlated with EGFR mutation (P=0.0003), and positively correlated with TP53 mutation (P=0.0001) and MET amplification (P=0.004). Patients with TP53 mutations had significantly higher MET amplification (P=0.007), and were more likely (P=0.0002) to be EGFR wild type. There was no correlation between KRAS mutation and overall PD-L1 expression, but significant positive correlation between PD-L1 expression and KRAS with TP53 co-mutation (P=0.0002). A cut-off for the ratio of MET: centromere signal was determined as 1.5%, and 4% of lung cancer patients were identified as MET amplified. CONCLUSIONS: This data suggests that in lung cancer both MET and TP53 play direct roles in regulating PD-L1 opposing EGFR. Moreover, KRAS and TP53 co-mutation may cooperate to drive PD-L1 expression in lung cancer. Adding MET or TP53 inhibitors to checkpoint inhibitors may be an attractive combination therapy in patients with lung cancer and MET amplification.

8.
Biomed Res Int ; 2016: 9027489, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27610384

RESUMO

Echinococcosis is a serious parasitic disease caused by Echinococcus tapeworms. Protoscoleces are sometimes released during surgical treatment for hydatid cysts, causing the recurrence of echinococcosis. Protoscoleces may be susceptible to radiation therapy. In this study Echinococcus protoscoleces were cultured in vitro and then divided into four different γ-ray irradiation dose groups (10 Gy, 20 Gy, 40 Gy, and 80 Gy) and a blank group. The protoscoleces were then implanted into the abdominal cavity of mice. Four months later, we observed that the incidence and weight of cysts declined with the increase of irradiation dose. γ-ray irradiation can suppress the generation of Echinococcus originated from protoscolex, the reason of which is due to the damaging to the structure of Echinococcus. Irradiation may prevent echinococcosis recurrence after surgical removal of hydatid cysts.


Assuntos
Equinococose/radioterapia , Echinococcus , Raios gama/uso terapêutico , Animais , Feminino , Camundongos
9.
J Synchrotron Radiat ; 22(4): 1062-71, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26134812

RESUMO

The characteristics of Friedel pairs in diffraction contrast tomography (DCT) are studied in the condition that the rotation axis of the sample is not exactly perpendicular to the incident X-ray direction. For the rotation axis approximately aligned along the vertical direction, the Friedel pairs close to the horizontal plane are insensitive to the non-perpendicularity of the rotation axis, and can be used to refine the sample-to-detector distance and X-ray energy, while the Friedel pairs close to the vertical direction are sensitive to the non-perpendicularity of the rotation axis, and can be used to determine the rotation axis orientation. The correct matching proportion of Friedel pairs decreases with increasing non-perpendicularity of the rotation axis. A method of data processing considering rotation axis misalignment is proposed, which significantly increases the correct matching and indexing proportions of the diffraction spots. A pure aluminium polycrystalline sample is investigated using DCT at beamline 4W1A of Beijing Synchrotron Radiation Facility. Based on the analysis of Friedel pairs, the sample-to-detector distance and X-ray energy are refined to be 8.67 mm and 20.04 keV, respectively. The non-perpendicular angle of the rotation axis is calculated to be 0.10°. With these refined geometric parameters, the matching proportion of the spatial position of diffraction spots is 90.62%. Three-dimensional reconstruction of the sample with 13 grains is realised using the algebraic reconstruction technique. It is demonstrated that the precise correction of the orientation of the sample rotation axis is effective in DCT suffering from rotation axis misalignment, and the higher accuracy in determining the rotation axis is expected to improve the reconstruction precision of grains.

10.
Radiat Prot Dosimetry ; 133(1): 20-4, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19211571

RESUMO

The cell killing abilities of soft X-rays on and off the oxygen K-shell edges on yeast cells have been investigated using a micrometer soft X-ray microprobe from synchrotron radiation. The dose depositions at different X-ray energies in the cell were discussed. At the same time, the cells were irradiated by (60)Co gamma-rays and the abilities in inducing yeast cell killing were compared with those produced by soft X-rays. The results showed that soft X-rays on and off the O(K) edge had higher ability of radiation damage than (60)Co gamma-rays. The total killing abilities of the three soft X-rays on yeast cells were almost similar and the differences of the X-rays in inducing yeast cell killing on and off the O(K) edge were not obvious.


Assuntos
Sobrevivência Celular/efeitos da radiação , Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/efeitos da radiação , Relação Dose-Resposta à Radiação , Doses de Radiação , Raios X
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(2): 331-4, 2008 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-18479016

RESUMO

To investigate the application of human finger nails in the diagnosis of cancer, Fourier transform infrared (FTIR) spectroscopy was employed to study the finger nails from some normal people and some with esophagus cancer and others with an operation for curing esophagus cancer five months ago. The results showed that there are obvious differences between FTIR spectra in them in spectral parameters such as frequency, intensity and band shape etc. The changes in the phosphate symmetric stretching vibration v(s) (PO2-) and asymmetric stretching vibration v(a)s(PO2-) modes are uniform, the v(s) (PO2-) and v(a)s(PO2-) absorption peaks of cancerous ones shift to high wave number compared with those of normal people, while those with operation shift to low wave number compared with those of cancerous ones. The C-O stretching vibration mode of protein located at 1 164 cm(-1) is composed of three absorption peaks located at 1 173.3, 1 158.0 and 1 151.1 cm(-1) respectively, meanwhile, the intensities and the wave numbers of the three peaks of cancerous ones all increase compared with normal people. The wave numbers of amide I and amide II of cancerous ones are both lower than those of normal people, while those with operation are between the cancerous ones and normal people, which suggest that the contents of protein and alpha-helix in finger nails of normal people, cancerous ones and the ones with operation are discriminative. The peak of bending vibration delta(CH2) mode of CH2 groups of protein lipid of cancerous ones shifts to high wave number slightly and the intensity of the peak weakens compared with that of normal people, which indicate that the methylene chain in the finger nails membrane lipids of cancerous ones is more ordered than that of normal people. Nevertheless, the peak of stretching vibration v(s) (CH2) of cancerous ones is lower than that of normal people, while that of the ones with operation is between cancerous ones and normal ones. As a result, the pathological changes in viscera can induce the changing of framework structure of phosphate in nucleic acid molecule of finger nails, and destroy the hydrogen bond of C-O(H) group in amino acid remnant group in finger nails. Furthermore, it also can decrease the C-O bond in keratin which participates in the action of hydrogen bond, and prompt the changing of content of keratin in finger nails, nevertheless the content of keratin in finger nails of cancerous ones can be resumed to level of normal people by operation.


Assuntos
Neoplasias Esofágicas/química , Unhas/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Dedos , Humanos , Proteínas/química
12.
Skeletal Radiol ; 35(3): 156-64, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16249900

RESUMO

PURPOSE: To study the early change of bone matrix and soft tissue around articulation in adjuvant-induced arthritic (AIA) rats non-invasively by X-ray phase-contrast imaging (XPCI), a new imaging method. MATERIALS AND METHODS: Adjuvant-induced arthritis was established in male Sprague-Dawley (SD) rats (n=6, age 40 days) by subcutaneous injection of Freund's complete adjuvant (FCA) into the left hindpaw. In vivo XPCI evaluation of the early soft tissue and bone changes in AIA rats was consecutively performed and correlated with changes in volumes of right hindpaws and body weights. In comparison, the changes in the AIA rats were also evaluated with absorption-contrast imaging using the same X-ray source as XPCI and conventional radiography at the same time. After the imaging evaluation, AIA rats were subjected to histological examination. RESULTS: There was significant difference between the score of XPCI and the other two methods in demonstrating soft tissue (P<0.01), bone details (P<0.01) and lesions (P<0.001). By day 10 after subcutaneous injection of FCA, bone changes in the right hindpaw were not obvious, but swelling of soft tissue appeared. By day 12, bone erosion in the articular facet and the area around the articular facet, was detected, along with osteoporosis, and swelling of soft tissue was aggravated. By day 14 bone erosions became fused and expanded, especially in the margin area around the articular facet. At day 16 bone erosion still existed. Joint interspaces seemed wider than normal, and swelling of soft tissue was significant. By day 18 periosteal new bone formation was seen definitely, destruction of bone decreased, bone density around the articular was enhanced, and swelling of soft tissue was relieved. XPCI could clearly distinguish all these alterations, which could not be demonstrated by absorption-contrast imaging and conventional radiography. During the test period, the volume of the right hindpaw and the body weight of the AIA rats also changed significantly compared with the normal rat. Histological examination confirmed that adjuvant-induced arthritis had occurred in all rats of the adjuvant group. CONCLUSION: Osteoporosis, bone erosion and periosteal new bone formation take place at the early stage of adjuvant-induced arthritis. XPCI can evaluate non-invasively these subtle bone changes that are "blind areas" for conventional radiography.


Assuntos
Artrite Experimental/diagnóstico por imagem , Análise de Variância , Animais , Artrite Experimental/patologia , Modelos Animais de Doenças , Progressão da Doença , Adjuvante de Freund , Membro Posterior , Inflamação/diagnóstico por imagem , Masculino , Radiografia , Ratos , Ratos Sprague-Dawley
13.
Zhonghua Nan Ke Xue ; 9(2): 124-8, 2003 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12749134

RESUMO

Soft X-ray microscopy is a microimaging technique using soft X-ray as illuminative source. It fills the gap between optical and electron microscopy. Soft X-ray microscopes have better resolution than visible microscopes. In comparison with electron microscopes, it can examine thick (up to 10 micrometers for biological samples) and wet specimens in their natural states without being dehydrated, sectioned and stained. In addition, soft X-ray microscopy can map elements and analyze the biological macromolecules such as protein and DNA in the examined samples. In this paper, the advantages of soft X-ray microscopy for biology are briefly described. The applications of soft X-ray microscopy to the analysis of mammal and human sperm are illustrated.


Assuntos
Microscopia/métodos , Espermatozoides/ultraestrutura , Raios X , Animais , Humanos , Masculino
14.
J Opt Soc Am A Opt Image Sci Vis ; 20(3): 588-95, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12630847

RESUMO

A high-resolution three-dimensional (3D) imaging technology has been developed, which is a combination of x-ray holography and computerized tomography (CT) technology called holographic computerized tomography (HCT). The theory and experimental techniques on biological specimens with the use of synchrotron radiation are discussed. Projections at different angles are reconstructed with the numerical method of in-line holography, and then the reconstructed data with a higher lateral resolution are used to restore the 3D image by the CT technique. With this method, the degradation caused by the diffraction of x rays is canceled, and 3D images with high resolution of micrometer magnitude in both the lateral and the longitudinal directions are obtained.


Assuntos
Holografia/métodos , Imageamento Tridimensional/métodos , Tomografia Computadorizada por Raios X , Animais , Aranhas , Raios X
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