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71.
The effects of air freezing (AF), immersion freezing (IF) and ultrasound-assisted immersion freezing (UF) at different power levels (125, 165, 205 and 245 W) on the structure and gel properties of the myofibrillar protein (MP) of chicken breast were investigated. UF at 165 W (UF-165) had no obvious negative impact on the primary structure of the MP and effectively reduced the change in the secondary and tertiary structure. In addition, UF-165 significantly reduced the losses in the elastic modulus (G′), gel strength, and gel water holding capacity (P < 0.05). According to low field nuclear magnetic resonance analysis, the T21 and T22 of the UF-165 MP gels were shorter than those of the AF and IF samples, which meant that the UF-165 reduced the mobility of the immobilized water and free water in MP gel. A scanning electron microscopy analysis showed that the appropriate ultrasonic power promoted the formation of a compact and homogeneous protein gel network. These results suggested that the appropriate ultrasonic power maintained the MP structure and reduced the loss of gel quality. 相似文献
72.
本研究选取18例男性乳腺恶性肿瘤患者作为研究组,纳入同期41例男性良性乳腺肿瘤及50例健康体检男性分别作为良性对照组和健康对照组,通过对比分析发现,研究组CDFI参数[搏动指数(PI)、阻力指数(RI)、血流速度(PSV)]高于良性对照组和健康对照组(P<O.05);PI、RI、PSV联合诊断男性乳腺恶性肿瘤的AUC高... 相似文献
73.
Ilknur Babahan Ali Özmen Mehran Aksel Mehmet Dincer Bilgin Rukiye Gumusada Muhammet Emin Gunay Fatih Eyduran 《应用有机金属化学》2020,34(7):e5632
In this study, a novel bidentate ligand containing oxime, hydrazone, and indole moieties and its BF2+-bridged transition metal complexes [Ni(II), Cu(II), and Co(II)] were synthesized and their cytotoxic activities against prostate and breast cancer cells were investigated. The vic-dioxime ligand bearing indole–hydrazone side groups was synthesized by reacting antiglyoximehydrazine (GH2) with 3-methoxy indole. The ligand forms mononuclear complexes with a metal-to-ligand ratio of 1:2 with M = Co(II)(H2O)2, Ni(II), and Cu(II). These metal complexes were then reacted with BF3(C2H5)2O to obtain BF2+-bridged transition metal complexes. The Co(II) complex of the ligand is proposed to be octahedral with water molecules as axial ligands, whereas the Ni(II) and Cu(II) complexes are proposed to be square planar. Spectral studies showed that the ligand bonded to the metal ion in a neutral bidentate fashion through the azomethine nitrogen atom and the imine oxime group. Structural assignments are supported by a combination of 1H nuclear magnetic resonance (NMR), 13C NMR, Fourier-transform infrared, LC/MS, elemental analyses, and magnetic susceptibility testing. For determining the cytotoxic effects of the novel anticancer products, cancer cells were cultured. The antiproliferative effects were determined using the MCF-7 breast cancer and PC-3 prostate cancer cell lines. The antiproliferative effects of the products were analyzed and their apoptotic or necrotic effects were determined with the Hoechst/propidium iodide double staining method in both cancer cell lines. Paclitaxel was used as the positive control (1 μm ). The results indicated that the newly synthesized compounds are effective on both cell lines between concentrations of 5 and 40 μm and show their effects by apoptotic mechanisms. Besides, these products were found to be more effective on the MCF-7 cell line. The cytotoxic efficiency of the newly synthesized products was more than that of paclitaxel (depending on concentration), which is a chemotherapeutic agent used in cancer therapy. 相似文献
74.
Dr. Yanyan Huang Dr. Xue You Lingna Wang Prof. Dr. Guanxin Zhang Dr. Shilang Gui Dr. Yulong Jin Prof. Dr. Rui Zhao Prof. Dr. Deqing Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(25):10128-10137
Tuning autophagy in a controlled manner could facilitate cancer therapy but it remains challenging. Pyridinium-substituted tetraphenylethylene salts (PTPE 1 — 3 ), able to target mitochondria and disrupt autophagy after forming complexes with albumin, are reported. Mitochondrion affinity and autophagy-inducing activity are improved by prolonging the length of alkyl chains in PTPE 1 – 3 . PTPE 1 – 3 demonstrate proautophagic activity and a mitophagy blockage effect. Failure of autophagosome–lysosome fusion in downstream autophagy flux results in cancer cell death. Moreover, fast formation of complexes of PTPE 1 – 3 with albumin in blood can facilitate biomimetic delivery and deep tumor penetration. Efficient tumor accumulation and effective tumor suppression are successfully demonstrated with in vitro and in vivo studies. PTPE 1 – 3 salts exhibit dual functionality: they target and image mitochondria because of aggregation-induced emission effects and they are promising for cancer therapy. 相似文献
75.
Yanyan Huang Xue You Lingna Wang Guanxin Zhang Shilang Gui Yulong Jin Rui Zhao Deqing Zhang 《Angewandte Chemie (International ed. in English)》2020,59(25):10042-10051
Tuning autophagy in a controlled manner could facilitate cancer therapy but it remains challenging. Pyridinium‐substituted tetraphenylethylene salts (PTPE 1 — 3 ), able to target mitochondria and disrupt autophagy after forming complexes with albumin, are reported. Mitochondrion affinity and autophagy‐inducing activity are improved by prolonging the length of alkyl chains in PTPE 1 – 3 . PTPE 1 – 3 demonstrate proautophagic activity and a mitophagy blockage effect. Failure of autophagosome–lysosome fusion in downstream autophagy flux results in cancer cell death. Moreover, fast formation of complexes of PTPE 1 – 3 with albumin in blood can facilitate biomimetic delivery and deep tumor penetration. Efficient tumor accumulation and effective tumor suppression are successfully demonstrated with in vitro and in vivo studies. PTPE 1 – 3 salts exhibit dual functionality: they target and image mitochondria because of aggregation‐induced emission effects and they are promising for cancer therapy. 相似文献
76.
R L Ehman G E Wesbey K L Moon R D Williams M T McNamara W R Couet T N Tozer R C Brasch 《Magnetic resonance imaging》1985,3(1):89-97
Nitroxyl spin labels have been shown to be effective in vivo contrast agents for magnetic resonance imaging (MRI) of the central nervous system, myocardium, and urinary tract. A new pyrrolidine nitroxyl contrast agent (PCA) with better resistance to in vivo metabolic inactivation than previously tested agents was studied for its potential to enhance subcutaneous neoplasms in an animal model. Twenty-two contrast enhancement trials were performed on a total of 15 animals 4-6 weeks after implantation with human renal adenocarcinoma. Spin echo imaging was performed using a .35 T animal imager before and after intravenous administration of PCA in doses ranging from 0.5 to 3mM/kg. The intensity of tumor tissue in the images increased an average of 35% in animals receiving a dose of 3 mM/kg. The average enhancement with smaller doses was proportionately less. Tumor intensity reached a maximum within 15 min of injection. The average intensity difference between tumor and adjacent skeletal muscle more than doubled following administration of 3 mM/kg of PCA. Well-perfused tumor tissue was more intensely enhanced than adjacent poorly perfused and necrotic tissue. 相似文献
77.
78.
Paul E Sijens Matthijs Oudkerk Pieter van Dijk Peter C Levendag Charles J Vecht 《Magnetic resonance imaging》1998,16(10):1273-1280
Fifteen percent loss in the peak area of choline containing compounds (Cho) was recently observed in 1H MR spectra of contrast-enhancing tumor at 5–10 min after Gd-contrast administration [Magn. Reson. Med. 37:222–225, 1997]. In this study, chemical shift imaging (CSI, 1500/135 ms PRESS) was used to assess the spectral changes in 47 Gd-enhancing glial brain tumors and metastatic brain tumors measured at 0–5, 5–10, and/or 10–15 min after administration of Gd-contrast. Percent Cho peak area losses measured at these times, 3 ± 3, 12 ± 2, and 14 ± 3 SEM, respectively, coincided with trends of line narrowing and up-field shift of the Cho peak. Significant changes in creatine and N-acetyl acetate signals were not observed. It is concluded that the Gd-induced loss of tumor Cho signal measured after 5 min, typically required for post contrast-MRI and the positioning of the CSI volume on tumor, shows little further change with time, if any. 相似文献
79.
Hybrid Nanoreactors: Enabling an Off‐the‐Shelf Strategy for Concurrently Enhanced Chemo‐immunotherapy
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Yannan Yang Dr. Jie Tang Dr. Prasanna Lakshmi Abbaraju Manasi Jambhrunkar Dr. Hao Song Min Zhang Dr. Chang Lei Jianye Fu Zhengying Gu Yang Liu Prof. Chengzhong Yu 《Angewandte Chemie (International ed. in English)》2018,57(36):11764-11769
Immunosuppressive tumors generally exhibit poor response to immune checkpoint blockade based cancer immunotherapy. Rationally designed hybrid nanoreactors are now presented that have integrated functions as Fenton catalysts and glutathione depletion agents for amplifying the immunogenic cell death and activating immune cells. A simple physical mixture of nanoreactors and chemodrugs in combination with immune checkpoint blockades show synergistically and concurrently enhanced chemo‐immunotherapy efficacy, inhibiting the growth of both treated primary immunosuppressive tumors and untreated distant tumors. The off‐the‐shelf strategy uses tumor antigens generated in situ and avoids cargo loading, and is thus a substantial advance in personalized nanomedicine for clinical translation. 相似文献
80.
The guaianolide ring containing sesquiterpene thapsigargin is found in the roots and fruits of Mediterranean plant Thapsia garganica L. It is known for its activity as a potent antagonist for Ca2+-ATPase (sarco–endoplasmic reticulum Ca2+-ATPase) inhibition. Recently, a prodrug mipsagargin is being investigated to target the blood vessel of the cancer cells for the treatment of tumors. The limited natural supply (low isolation and only localized growth (Mediterranean area)) from the natural sources strongly urges for the development of chemical synthetic strategies to access these natural products. This review pertain the various strategies used so far in the thapsigargin’s synthesis, focusing on major contributions in the total synthesis till date. 相似文献