One-stop strategy for treatment of atrial fibrillation: feasibility and safety of combining catheter ablation and left atrial appendage closure in a single procedure / 中华医学杂志(英文版)

BACKGROUND@#Catheter ablation is effective in restoring sinus rhythm and left atrial appendage closure (LAAC) is increasingly used for stroke prevention in patients with atrial fibrillation (AF). We aimed to observe the feasibility and safety of performing AF ablation and LAAC in a single (one-stop) procedure.@*METHODS@#Consecutive AF patients who underwent the combined procedure of AF ablation and LAAC with WATCHMAN device between March 2017 and September 2018 were prospectively enrolled. Baseline and intra-procedural parameters were evaluated. Three-month and subsequent 1-year follow-up were performed in all and earlier-enrolled subjects, respectively.@*RESULTS@#A total of 178 AF patients (94 males, 68.9 ± 8.1 years) underwent the one-stop procedure with CHA2DS2-VASc score 3.3 ± 1.5 and HAS-BLED score 1.6 ± 1.0, respectively. Pulmonary vein isolation was achieved in all patients while additional linear ablation was applied if the operator deemed necessary, yielding immediate ablation success rate of 98.9% (176/178). In the subsequent LAAC, satisfactory seal (residual leak <5 mm) was achieved in all patients. One stroke and four cardiac perforations occurred peri-operatively. At 3-month follow-up, sinus rhythm and satisfactory seal were maintained in 153/178 (86.0%) and 178/178 (100%) patients, respectively. One stroke and one delayed cardiac tamponade occurred, while no device-related thrombus or device migration was observed. During the 1-year follow-up for the earlier enrolled subjects, 52/72 (72.2%) of the patients maintained sinus rhythm. There was no stroke or systemic embolism observed.@*CONCLUSION@#Combining catheter ablation and LAAC in a single procedure can be successfully and safely performed in non-valvular AF patients of Chinese population.

Serum peptidome profiling for identifying pathological patterns in patients with primary nephrotic syndrome / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Renal biopsy is necessary for diagnosing the pathological changes of primary nephrotic syndrome (NS). However, it is invasive, time-consuming and can not be performed frequent on the same patient. Thus, development of a non-invasive and rapid diagnostic method may improve clinical patient management.</p><p><b>METHODS</b>Proteomic tool magnetic bead-based matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MB-based MALDI TOF MS) was applied to serum to determine peptidome patterns that are characteristic of different pathological changes.</p><p><b>RESULTS</b>Serum specimen from 114 patients with NS (62 were minimal change disease (MCD), 30 were membranous nephropathy (MN), and 22 were focal segmental glomerulosclerosis (FSGS)) and 60 normal individuals were analyzed using MB-based MALDI TOF MS. The peptidome pattern was generated by genetic algorithms using a training set of 31 MCD, 15 MN, 11 FSGS and 30 normal individuals and was validated by an independent testing set of the remaining samples. The serum peptidome pattern, based on a panel of 14 peaks, accurately recognized samples from MCD, MN, FSGS and healthy control with sensitivities of 93.5%, 86.7%, 63.6% and 90.0%, and specificities of 98.2%, 94.4%, 100% and 89.5%, respectively. Moreover, one peptide from peptidome pattern was identified by liquid chromatography tandem mass spectrometry (LC MS/MS) as fibrinogen A.</p><p><b>CONCLUSION</b>Detection of the serum peptidome pattern is a rapid, non-invasive, high-throughout, and reproducible method for identifying the pathological patterns of patients with nephrotic syndrome.</p>

High mobility group box-1 stimulates proinflammatory cytokine production in endothelial cells via MAP kinases / 南方医科大学学报

<p><b>OBJECTIVE</b>To examine the synergistic effect of recombinant human high mobility group box 1 (HMGB1) protein and lipopolysaccharides (LPS) on the release of interleukin-8 (IL-8) and monocyte chemotactic protein 1 (MCP-1) in human umbilic vein endothelial cells (HUVECs), and explore the role of mitogen-activated protein kinases (MAPK) signal transduction in cytokine release.</p><p><b>METHODS</b>HUVECs were incubated with recombinant HMGB1 (0-75 ng/ml) for 24 h and the culture medium supernatant was harvested for detection of IL-8 and MCP-1 with LiquiChip system. At 0, 1, 3, 6, 12 and 24 h after stimulation with 15 ng/ml HMGB1 or 15 ng/ml HMGB1 plus 10 ng/ml LPS, the levels of IL-8 and MCP-1 in the HUVECs were examined. To test the effect of MAPK inhibitors, HUVCs were pretreated with the inhibitors SB203580 (20 mol/L), PD98059 (20 mol/L), and JNK inhibitor II (50 nmol/L) 1 h before HMGB1 and LPS stimulation.</p><p><b>RESULTS</b>The levels of IL-8 and MCP-1 were significantly increased in the HUVECs stimulated with HMGB1 protein at the concentrations of 3, 15 and 75 ng/ml in comparison with the control levels (P<0.01). Since 3-6 h after the stimulation with HMGB1, the levels of IL-8 and MCP-1 began to increase gradually, and steadily increased at 12 and 24 h, all significantly higher than those of the control group (P<0.01). Stimulation of the HUVECs with LPS (10 ng<ml) or HMGB1 (15 ng/ml) alone resulted in significantly increased levels of IL-8 and MCP-1 (P<0.01), which were further increased after costimulation with LPS and HMGB1, suggesting a synergistic effect between HMGB1 and LPS (P<0.01). This synergistic effect was significantly inhibited by pretreatment with MAPK signaling kinases inhibitors, especially the p38 MAP kinase inhibitor SB203580, and the cocktail of MAP kinase inhibitors almost totally blocked the expression of these chemokines in HUVECs treated with HMGB1 and LPS.</p><p><b>CONCLUSION</b>HMGB1 protein can activate HUVECs to produce the chemokines IL-8 and MCP-1 in a dose- and time-dependent manner. HMGB1 also acts synergistically with LPS to induce IL-8 and MCP-1 release, which might play an important role in the development of sepsis. MAPK signal transduction plays an important role in HMGB1 and LPS-induced IL-8 and MCP-1 release.</p>

Extraction and two-dimensional liquid chromatographic fractionation of plasma membrane proteome of mouse liver cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To extract the plasma membrane proteins from mouse liver cells and investigate the approach for fractionating the protein mixtures by two-dimensional liquid chromatography.</p><p><b>METHODS</b>The plasma membrane of the liver cells from 10 mice was extracted by differential centrifugation and sucrose density-gradient centrifugation. The plasma membrane proteins were exchanged with the start buffer and separated by chromatofocusing in the first-dimensional fractionation. The final results were transformed into UV/pI maps using ProteoVue software.</p><p><b>RESULTS</b>We successfully extracted the plasma membrane proteins from mouse liver cells. Sixteen fractions between pH 8.5-4.0 were recovered in the first-dimensional chromatofocusing followed by 2D- chromatographic fractionation, and the results were displayed as UV/pI maps.</p><p><b>CONCLUSION</b>This approach for fractionating the mouse liver cell plasma membrane protein study provides the foundation for further studies on the functions of plasma membrane proteins and differential proteome of diseases.</p>

Analysis of Toll-like receptor 4 and myeloid differentiation protein-2 interaction with fluorescence resonance energy transfer / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the interaction between Toll-like receptor (TLR) 4 and myeloid differentiation protein-2 (MD-2) in living cells using fluorescence resonance energy transfer (FRET) technology.</p><p><b>METHODS</b>The coding sequences of TLR4 and MD-2 (without the signal peptide sequence) were amplified by PCR and cloned into enhanced cyan fluorescence protein (CFP) and enhanced yellow fluorescence protein (YFP) expression vectors carrying TLR4 signal peptides (pECFP-C1-SP and pEYFP-C1-SP). HEK293 cells were transfected respectively or together with the reconstructed plasmids verified by enzyme digestion and sequence analysis, and the expression and sublocalization of these fluorescence proteins in the cells were observed using fluorescence microscope. FRET in the cells coexpressing CFP-TLR4 and YFP-MD-2 was detected using routine and acceptor photobleaching method.</p><p><b>RESULTS</b>The reconstructed plasmids were expressed in HEK293 cells. The cyan or yellow fluorescence was located in the cytoplasm, mainly around the nucleus in the cells transfected with pECFP/TLR4 or pEYFP/MD-2, and both the cyan and yellow fluorescence located mainly in the membrane and occasional in the cytoplasm of cells cotransfected with pECFP/TLR4 and pEYFP/MD-2. Routine or acceptor photobleaching detected FRET phenomena in cells coexpressing CFP-TLR4 and YFP-MD-2, suggesting direct interaction between TLR4 and MD-2.</p><p><b>CONCLUSION</b>This study provides direct evidence of the interaction between TLR4 and MD-2 in living cells.</p>