ABSTRACT
<p><b>OBJECTIVE</b>To monitor the 3-dimensional (3D) morphological changes of C6/36 cells during dengue virus (DENV) infection using a live-cell imaging technique based on digital holographic microscopy and provide clues for better understanding the mechanisms of DENV infection.</p><p><b>METHODS</b>C6/36 cells were seeded in 6-well plates to determine the optimal imaging density under a holographic cell imager, and the morphological changes of the cells were recorded in response to a culture temperature change from 28 degrees celsius; to 37 degrees celsius; C6/36 cells were infected with 4 DENV strains with different serotypes at 28 degrees celsius; and incubated at 37 degrees celsius; for 24 h, and the 3D holograms and relevant morphological parameters were recorded at different time points using HoloMonitor M4 holographic cell imaging and analysis system.</p><p><b>RESULTS</b>The holograms of C6/36 cells inoculated at the optimal density for imaging (4×10per well) showed unified 3D morphologies of the single cells with minimal dispersions in the cell area, thickness and volume (P<0.05), which did not undergo obvious changes when the cells were incubated at 37 degrees celsius; for 24 h (P>0.05). The cell area and volume of the cells infected with the 4 DENV strains all increased and the cell thickness was reduced during incubation. Among the 4 strains, DENV-1 and DENV-2 caused reduced cell thickness while DENV-3 and DENV-4 increased the cell thickness, and the pattern and degree of such changes differ among the 4 strains.</p><p><b>CONCLUSIONS</b>Digital holographic microscopy allows monitoring of the complex morphological changes of cells during DENV infection. The 4 DENV strains with different serotypes causes characteristic cell damages during infection.</p>
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of ginsenoside Rb1 on cerebral infarction volume as well as IL-1 beta in the brain tissue and sera of focal cerebral ischemia/reperfusion (I/R) injury model rats.</p><p><b>METHODS</b>The I/R rat model was established by using thread according to Zea-Longa. SD rats were randomly divided into five groups, i.e., the sham-operation group, the model group, the low dose ginsenoside Rb1 (20 mg/kg) group, the medium dose ginsenoside Rb1 group (40 mg/kg), and the high dose ginsenoside Rb1 group (80 mg/kg), 12 in each group. Rats in the sham-operation group only received middle cerebral artery occlusion (MCAO) but without thread insertion. The MCAO model was prepared in the rest 4 groups, followed by MCAO2 h later. Ginsenoside Rb1 at each dose was peritoneally administrated to rats in corresponding groups immediately after cerebral ischemia. Equal volume of normal saline was administered to rats in the sham-operation group. Rats' cerebral infarction volume, integrals of neurologic defect degree, expression of IL-1 beta content in the brain tissue and sera were observed 24 h after 2-h cerebral I/R.</p><p><b>RESULTS</b>In the model group, integrals of neurologic defect degree were improved (P < 0.01), IL-1 beta positive cells in the brain tissue increased and serum IL-1 beta content elevated (P < 0.05), when compared with the sham-operation group. In comparison of the model group, integrals of neurologic defect degree were lowered in the medium dose and high dose ginsenoside Rb1 groups (P < 0.05, P < 0.01). The cerebral infarction volume was all shrunken in each ginsenoside Rb1 group, IL-1 beta positive cells in the brain tissue decreased, and IL-1 beta content in serum reduced (P < 0.01, P < 0.05). Compared with the low dose ginsenoside Rb1 group, integrals of neurologic defect degree decreased, the cerebral infarction volume shrunken, and IL-1 beta content in serum reduced in the high dose ginsenoside Rb1 group (P < 0.01, P < 0.05).</p><p><b>CONCLUSION</b>Ginsenoside Rb1 (20, 40, 80 mg/kg) might effectively release local cerebral ischemia by down-regulating the IL-1 beta expression.</p>