Influence of splenic high mobility group box-1 protein on immune function of regulatory T lymphocytes in scald rats / 中华烧伤杂志

<p><b>OBJECTIVE</b>To observe the influence of high mobility group box-1 protein (HMGB1) derived from spleen on the phenotype of regulatory T lymphocytes (Treg) and HMGB1-mediated immune function in severely scalded rats after delayed resuscitation.</p><p><b>METHODS</b>One hundred and four Wistar rats were divided into normal control group (NC, n = 8), sham scald group (SS, n = 32), scald group (S, n = 32), and ethyl pyruvate (EP) treatment group (EPT, n = 32) according to the random comparison table. Rats in the latter 2 groups were subjected to 30%TBSA full-thickness scald, which were intraperitoneally injected with Ringer solution or EP solution at post scald hour (PSH) 6 (delayed antishock treatment) and administered with 4 mL Ringer solution or EP solution per 12 hours after PSH 12 till PSH 48. Rats in SS group were treated the same as that of S group except for sham scald with 37 degrees C water. Injured rats were sacrificed at post scald day (PSD) 1, 3, 5, 7 (rats in NC group were also sacrificed), and CD4(+)CD25(+)Treg were isolated from spleen with magnetic-activated cell sorting method. The content of HMGB1 in spleen and IL-2 level in supernatant were determined with ELISA. The expression of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) on Treg was determined with flow cytometry, and the proliferation activity of T lymphocytes was also detected (recorded as absorbance value). Data were processed with analysis of variance among groups and independent samples t test.</p><p><b>RESULTS</b>(1) Compared with that of rats in SS group and EPT group, the expression of splenic HMGB1 in S group increased significantly on PSD 1 through PSD 7 [peaked on PSD 1: (46.7 +/- 8.3) ng/mg protein]. (2) Compared with that in SS group, the expression of CTLA-4 in S group was enhanced significantly on PSD 1 through PSD 5 (with t value respectively 10.459, 12.051, 4.029, P < 0.05 or P < 0.01); while that in EPT group decreased significantly on PSD 1 through PSD 7 as compared with that from S group (with t value respectively 2.796, 9.913, 9.581, 10.022, P < 0.05 or P < 0.01). (3) Compared with that of rats in SS group, the proliferation activity of T lymphocytes in S group was markedly suppressed on PSD 1 through PSD 7 (nadir on PSD1: 0.167 +/- 0.059), and release of IL-2 was decreased significantly [nadir on PSD 5: (44 +/- 24) pg/mL]. T lymphocytes proliferation activity was restored and excretion of IL-2 increased in EPT group as compared respectively with that of S group at each time point.</p><p><b>CONCLUSIONS</b>The release of HMGB1 may stimulate splenic Treg to mature, thereby induce suppression of proliferation activity of T lymphocytes and immune function. EP can ameliorate immune dysfunction in animals with delayed resuscitation through inhibiting the synthesis and release of HMGB1.</p>

Isolation and identification of arboviruses from mosquito pools in some regions of Liaoning province,China / 中华流行病学杂志

Objective To isolate and identify arboviruses from mosquito pools in some regions of Liaoning province.Methods Mosquitoes were collected from Shenyang,Yingkou,Panjin,Jinzhou and Dandong cities of Liaoning province in 2006.Viruses were isolated by inoculating the specimens onto C6/ 36 and BHK-21cells.The new isolates were identified using serological and molecular biological methods.Results 5410 mosquitoes were collected from the five cities in total.Three isolates produced CPE in C6/ 36 cell and five isolates produced CPE in both C6/36 and BI-IK-21 cell.Three isolates (LN0684,LN0688 and LN0689) were identified as Banna virus and one isolate (LN0636) was identified as Getah virus.Phylogenetic analysis showed that the three Banna virus strains were clustered into the same evolution branch as the other Chinese isolates.The identity of nucleotide sequence was between 91.2% and 94.7%,compared with other Banna virus strains.The new isolated Getah virus was clustered into the same branch with the strain of South Korea (swine).The identity of nucleotide sequence was 99.2%,when comparing with the strain of South Korea and was 95% to 99% with the strains fi'om Russia,mainland of China and Taiwan region.Conehmion Eight virus isolates,including three Banna virus,one Getah virus and four unknown virus strains were isolated from mosquitoes in Liaoning province.Banna virus and Getah virus were reported for the first time in Liaoning province,while Getah virus showed the highest nucleotide homology with the South Korea strains.

Significance of changes in plasma bactericidal/permeability-increasing protein levels in patients with severe surgical infection / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate changes in endogenous bactericidal/permeability-increasing protein (BPI) levels and their significance in patients with surgical sepsis.</p><p><b>METHODS</b>In the prospective study, 19 surgical patients with infection were involved. The plasma BPI, lipopolysaccharide-binding protein (LBP) and interleukin-6 levels were measured on post-infected days 1, 3, 5, 7 and 14 by an enzyme-linked immunosorbent assay (ELISA). Plasma endotoxin concentrations were determined by the modified chromogenic Limulus Amebocyte Lysate (LAL).</p><p><b>RESULTS</b>Compared with normal controls, significant lower plasma BPI/LBP ratios were observed in septic patients on days 1 to 5 after infection (P < 0.01), and in severe septic patients on days 1 to 7 (P < 0.01). Moreover, plasma BPI/LBP ratios were much lower in severe sepsis than those in sepsis on days 1 to 3 after infection (P < 0.05).</p><p><b>CONCLUSIONS</b>Plasma BPI and LBP levels increased rapidly after infection, but BPI/LBP ratios were significantly decreased during sepsis. Plasma BPI/LBP ratios appear to be closely related to the severity of sepsis in patients complicated by surgical infection.</p>

The potential role of high mobility group-1 protein in the pathogenesis of sepsis-induced multiple organ dysfunction syndrome in rats / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the potential role of high mobility group-1 protein (HMG-1) in the pathogenesis of sepsis-induced multiple organ dysfunction syndrome in rats.</p><p><b>METHODS</b>Using a sepsis model by cecal ligation and puncture (CLP), 80 male Wistar rats were randomly divided into four groups: normal control (n = 10), sham operation (n = 10), CLP (subdivided into 2, 6, 12, 24, 48, 72 h post-CLP, n = 60), and sodium butyrate treatment (subdivided into 12, 24 h post-CLP, n = 20). At serial time points in each group, animals were sacrificed, and blood as well as tissue samples from the liver, lung, kidney and small intestine were harvested to measure organ function parameters and HMG-1 mRNA expression by the reverse transcription polymerase chain reaction (RT-PCR) taking GAPDH as an internal standard. Also, additional experiments were performed to observe the effect of treatment with sodium butyrate on survival rate in septic rats (n = 57).</p><p><b>RESULTS</b>HMG-1 mRNA levels significantly increased in various tissues during 6 - 72 h after CLP (P < 0.05 or 0.01), and were markedly inhibited by sodium butyrate at 12 h and 24 h (P < 0.05 or 0.01). Early treatment with sodium butyrate also could markedly reduce serum alanine aminotransferase, creatinine levels at 12 h post-CLP and pulmonary myeloperoxidase activities at 24 h. Furthermore, treatment with sodium butyrate could significantly improve the 1- to 6-day survival rates in animals subjected to CLP (P < 0.05 or 0.01).</p><p><b>CONCLUSIONS</b>HMG-1 might play an important role in the development of excessive inflammatory response and subsequent multiple organ dysfunction syndrome.</p>