RESUMO
Carbon dots (CDs) possess the merits such as energy efficiency, green sustainability and environmental friendliness, comparing with top-down synthesis methods at higher pressure or temperature condition. Here, a variety of emission states CDs were prepared by using the method of room temperature chemistry by selecting green raw materials such as glucose, p-phthalaldehyde and m-diethylaminophenol. The luminescence mechanism was studied in detail. The luminescent center of blue emitting carbon dots (B-CDs) and green emitting carbon dots (G-CDs) is CO bond, and the increased contents of CO bond lead to the creation of new energy levels between the energy gaps of HOMO and LUMO levels, which results in the red shift of luminescence wavelength. The emission state of red emitting carbon dots (R-CDs) is due to the formation of amino N. In addition, R-CDs have an exclusive respond to dopamine (DA) and are regarded as good fluorescent probes for detecting DA. Furthermore, the addition of ascorbic acid (AA) restores the luminescence of R-CDs quenched by DA. Therefore, R-CDs has great application potential as a selective fluorescent "turn on-off" probe.
RESUMO
In order to study the construction of digital three-dimensional model of rabbit vascular network and provide a powerful basis for the model construction and image processing of human vascular network, in this study, rabbit abdominal and pelvic vessels are perfused with latex-bismuth oxide contrast agent. After that, the internal fibrous structure of the abdominal and pelvic vascular network in rabbits is studied by micro-computed tomography (Micro-CT). Angiography and post-processing software are performed. Firstly, six female rabbits are selected as the study subjects and are anesthetized by intraperitoneal injection of 12% chloral hydrate. After complete anesthesia, laparotomy is performed on the rabbits. The abdominal wall of the rabbit is cut longitudinally to expose the pelvic and abdominal cavity completely. The posterior peritoneum is found and opened. The catheter is inserted into the abdominal aorta and renal artery to complete the abdominal aorta and arterial intubation. Latex, bismuth oxide and potassium hydroxide are mixed in a ratio of 1:1:1 to form latex-bismuth oxide mixed solution as a mixed contrast agent for blood vessel perfusion. After the rabbit is perfused with mixed contrast medium, four organs, including bladder, uterus, small intestine and kidney, are selected as the research organs to construct the three-dimensional model of vascular network in this study. Finally, the above organs are scanned in vitro by micro-CT technology, and the original images of each organ are processed. Then, Mimics 17.0 software is used to build a digital three-dimensional model of the abdominal and pelvic vascular network in rabbits, obtain the information parameters of each network, and analyze the classification and diameter of blood vessels. The results show that the classification of bladder vascular network can only be divided into two levels, uterine vascular network can be divided into three levels, and small intestine and kidney vascular network can be divided into four levels. Therefore, the combination of micro-CT scanning and contrast agent can successfully construct a digital three-dimensional model of rabbit vascular network, which provides a new idea and method for the study of human abdominal and pelvic organs and physiological characteristics.
RESUMO
In order to effectively apply the high-fat cell model to the regulation of vascular homeostasis and the repair of vascular endothelial cell injury, and to provide a new theoretical basis for the treatment of vascular homeostasis imbalance in the future, in this study, the mouse thoracic aorta tissue is extracted by using mouse endothelial cells. Western blotting and immunofluorescence resonance energy transfer (Immuno-FRET) are then used to verify the distribution and physical coupling properties of TRPV4 and Nox2 in cells. Finally, mouse mesenteric endothelial cells are isolated and cultured to induce FFA high-fat cell model. The results show that the nucleic acid expression levels of TRPV4 and Nox2 in RNA are significantly different from those of TRPV4 and Nox2 in protein. The relative values of TRPV4 and Nox2 in the control group are relatively low (0.8⯱â¯0.11). However, the relative values of TRPV4 and Nox2 are higher in the FFA high-fat cell model induced by the experimental group, and the values are (1.7⯱â¯0.8). Obviously, the relative values of TRPV4 and Nox2 in the experimental group are higher than those in the control group. The expression of reactive oxygen species (ROS) in vascular endothelial cells of control group is (1.0⯱â¯0.16), and that in FFA group is (2.5⯱â¯0.46). The expression of ROS in FFA cell model with HC067047A inhibitor is (1.5⯱â¯0.38). In the FFA cell model with apo inhibitor, ROS expression is (1.2⯱â¯0.23). Thus, in the FFA high-fat cell model induced successfully, the physical coupling of TRPV4 and Nox2 increases in primary endothelial cells, and the increase of physical coupling of TRPV4 and Nox2 results in the increase of ROS expression, which also means the imbalance of ROS homeostasis in vascular endothelial cells and the change of vascular endothelial cell permeability. The expression levels of TRPV4 and Nox2 are used as indicators of whether the vascular function is stable or unbalanced, thus providing a new theoretical basis for the treatment of cardiovascular diseases.
RESUMO
Chemical studies on the roots of Fraxinus rhynchophylla led to the isolation of fraxisecoside (1), a novel coumarin-secoiridoid hybrid glycoside, namely, fraxetin-8-O-[11'-methyl-oleosidyl-(7'-->6'')]-beta-D-glucopyranoside and 14 known compounds. Their structures were elucidated based on chemical evidence and spectroscopic analysis, including extensive 2D NMR methods. Compound 2 was first isolated as a pure compound. Compound 1 exhibited moderate PTP1B inhibition activity. Compounds 1 and 2 showed inhibition activity against B- and T-cell proliferation, without cytotoxicity.
