Kinetin inhibits proliferation of hepatic stellate cells by interrupting cell cycle and induces apoptosis by down-regulating ratio of Bcl-2/Bax / 华中科技大学学报（医学）（英德文版）

Liver fibrosis is an important health problem that can further progress into cirrhosis or liver cancer, and result in significant morbidity and mortality. Inhibiting proliferation and inducing apoptosis of hepatic stellate cells (HSCs) may be the key point to reverse liver fibrosis. At present, anti-fibrosis drugs are rare. Kinetin is a type of plant-derived cytokinin which has been reported to control differentiation and induce apoptosis of human cells. In this study, the HSCs were incubated with different concentrations of kinetin. The proliferation of rat HSCs was measured by MTT assay, cell cycle and apoptosis were analyzed by flow cytometry, and the apoptosis was examined by TUNEL method. The expression of Bcl-2 and Bax proteins was detected by immunocytochemistry staining. It was found that kinetin could markedly inhibit proliferation of HSCs. In a concentration range of 2 to 8 μg/mL, the inhibitory effects of kinetin on proliferation of HSCs were increased with the increased concentration and the extension of time (P < 0.01). Flow cytometry indicated that kinetin could inhibit the DNA synthesis from G0/G1 to S phase in a dose-dependent manner (P < 0.01). The apoptosis rates of the HSCs treated with 8, 4 and 2 μg/mL kinetin (25.62% ± 2.21%, 15.31% ± 1.9% and 6.18% ± 1.23%, respectively) were increased significantly compared with the control group (3.81% ± 0.93%) (P < 0.01). All the DNA frequency histogram in kinetin-treated groups showed obvious hypodiploid peak (sub-G1 peak), and with the increase of kinetin concentrations, the apoptosis rate of HSCs also showed a trend of increase. It was also found that kinetin could down-regulate the expression of Bcl-2, and up-regulate the expression of Bax, leading to the decreased ratio of Bcl-2/Bax significantly. The kinetin-induced apoptosis of HSCs was positively correlated with the expression of Bax, and negatively with the expression of Bcl-2. It was concluded that kinetin can inhibit activation and proliferation of HSCs by interrupting the cell cycle at G1/S restriction point and inducing apoptosis of HSCs via reducing the ratio of Bcl-2/Bax.

A clinical analysis of 33 cases of Kimura's disease / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To improve the diagnosis and treatment of Kimura's disease (KD) by investigating its clinical characteristics, pathological features and complications.@*METHOD@#The clinical data of 33 cases of KD were analyzed retrospectively.@*RESULT@#Of 33 cases, 22 showed the mass on head and neck, while in the other cases, the mass distributed in the region of groin, axillary fossa, hilum of lung and mesentery. Regional lymph nodes were involved in 21 cases and major salivary glands were invaded in 8 cases. Twenty-three cases had typical peripheral eosinophilia, although only in 2 patients the quantity of serum total IgE increased markedly. Urine abnormalities happened to 7 cases, such as massive proteinuria (3 cases) and hematuria (2 cases). Among 6 cases which underwent bone marrow aspiration, 2 showed eosinophilia. Two cases were complicated with nephritic syndrome. Six cases were combined with local inflammation on head and neck and 2 cases were combined with malignant tumor.@*CONCLUSION@#Mass on the head and neck is the typical clinical manifestation in KD, with regional lymph nodes and major salivary glands involved most. Serum total IgE and histopathologic examination should always be done to confirm KD, especially in the cases with unknown eosinophilia increasing.

ROS-mediated ERK activation in delayed protection from anoxic preconditioning in neonatal rat cardiomyocytes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The activation of extracellular signal-regulated kinase1/2 (ERK1/2) has been shown to be important signaling pathway in the ischemic preconditioning (IPC) response. Recently, some studies suggest a key role for the mitochondrial ATP-sensitive potassium channel (mKATP) as both a trigger and an end effector of acute and delayed protection of IPC. Hence, this study was undertaken to elucidate the relationship between mKATP and ERK1/2 in the delayed protection mechanism of anoxic preconditioning (APC).</p><p><b>METHODS</b>An APC model was established using cultured neonatal rat cardiomyocytes. Pharmacological agents [diazoxide, 5-hydroxydecanoate (5-HD), 2-mercaptopropionylglycine (MPG), and PD98059] were used to modulate mKATP and ERK1/2 activation. Cellular injury was evaluated by measuring cellular superoxide dismutase (SOD) activity, cell viability, and lactate dehydrogenase (LDH) release. The generation of cellular reactive oxygen species (ROS) and the activation of ERK1/2 were determined at different time points starting from the beginning of preconditioning with anoxia or diazoxide (an mKATP opener).</p><p><b>RESULTS</b>Cell viability and SOD activity in the APC [(81.9 +/- 11.4)%, (13.6 +/- 3.7) U/L] and diazoxide [(79.2 +/- 12.4)%, (16.5 +/- 4.6) U/L] groups were significantly higher than in the anoxia/reoxygenation (A/R) [(42.2 +/- 7.3)%, (8.8 +/- 2.8) U/L] group (all P < 0.01). LDH activity in the APC group [(101.9 +/- 18.9) U/L] and diazoxide group [(97.5 +/- 17.7) U/L] was significantly lower than in the A/R group [(250.5 +/- 43.6) U/L] (all P < 0.01). Both APC and diazoxide simultaneously facilitated intracellular ROS generation and rapid ERK1/2 activation. But the effects of APC and diazoxide were remarkedly attenuated by 5-HP (an mKATP blocker) and by MPG (a free radical scavenger). In addition, the ERK1/2 inhibitor PD98059 also abolished the cellular protective effects induced by diazoxide.</p><p><b>CONCLUSION</b>mKATP may mediate ERK1/2 activation during anoxia preconditioning by generating ROS, which then triggers the delayed protection of APC in rat cardiomyocytes.</p>

Different roles of ERK(1/2) and p38 MAPK(alpha/beta) in cellular signaling during cardiomyocyte anoxia preconditioning / 生理学报

Preconditioning (PC) exhibits earlier and delayed protection. But the mechanism of cellular signaling in delayed protection of PC remains unclear. We explored the roles of ERK(1/2) and p38 MAPK(alpha/beta) (p38(alpha/beta)) in delayed protection of anoxia preconditioning (APC). The anoxia/reoxygenation (A/R) injury and APC models were established in cultured neonatal rat cardiomyocytes. An ERK(1/2) inhibitor (PD98059) and a p38(alpha/beta) blocker (SB203580) were applied and their effects on A/R and APC models were observed. The cellular contents of MDA, SOD, cell viability and LDH release was measured at the end of the study. ERK(1/2) and p38 MAPK total activity was measured by in-gel myelin basic protein phosphorylation assay at different points during sustained anoxia. The results obtained are as follows: (1) PD98059 (but not SB203580), administered in preconditioning anoxia phase in APC group, abolished completely the delayed protection of APC; (2) SB203580 administered in sustained anoxia phase in A/R group could relieve cell injury induced by anoxia, but not by PD98059; (3) the highest activity of ERK(1/2) and p38 MAPK induced by anoxia appeared at 4 h after the beginning of sustained anoxia. APC inhibited the over activation of both ERK(1/2) and p38 during the following sustained anoxia. These results suggest that ERK(1/2) activation during preconditioning may be an important link of cell signal transduction in the mechanism of APC delayed protection. p38(alpha/beta) activation at the preconditioning stage dose not participate in signaling of APC delayed protection. The excessive activation of p38(alpha/beta) is possibly a key factor in mediating cell injury induced by sustained anoxia. The inhibition of p38(alpha/beta) excessive activation during subsequent sustained anoxia might play a role in delayed protection mechanism of APC.

Influence of SEN virus infection on their response to lamivudine in patients with chronic hepatitis B / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the influence of SEN virus infection on their response to lamivudine in patients with chronic hepatitis B (CHB).</p><p><b>METHODS</b>SEN virus-D and -H DNA were detected in 45 CHB patients who received lamivudine 12 months with nested-PCR, and YMDD motif mutations in HBV DNA were investigated with gene chip.</p><p><b>RESULTS</b>The positive rate of SEN virus DNA was 11.1% (5/45), and there were four out of the five SEN virus DNA positive patients whose HBV DNA was positive, among them, two patients existed YMDD motif mutation. While ten out of the forty SEN virus DNA negative patients appeared HBV DNA positive. The response rate was significant lower in SEN virus-infected patients than that in uninfected patients (chi 2=3.97, P<0.05).</p><p><b>CONCLUSION</b>Coinfection with SEN virus in chronic hepatitis B patients may adversely affect the outcome of treatment with lamivudine</p>