[Exploration of the broken parts of a brake hose by ATR-FTIR and SEM].

ATR-FTIR and SEM were respectively utilized to analyze the chemical components and to observe the micromorphology of a broken brake hose from a traffic case, which could be a supplementary for the traditional microscopic examination. The instrumental analysis results indicated that the rubber from the brake hose had already aged; the rubber from external side had experienced brittle fracture and there were original hollows in the rubber from internal side. The breaking of the brake hose resulted from all these reasons. The experimental results also demonstrated that the fact could be reflected efficiently, accurately and objectively by the application of ATR-FTIR and SEM to the physical evidence from a case. Therefore, it could be an effective complement for traditional traffic trace examination.

Annexin 1-derived peptide Ac2-26 inhibits eosinophil recruitment in vivo via decreasing prostaglandin D2.

BACKGROUND: Asthma is a chronic inflammatory disease of the mucosa and is associated with excess TH2 cytokines, eotaxin, prostaglandin D2 (PGD2) and eosinophilia in the lungs. Previous studies have emphasized that the N-terminal peptide of annexin 1 (peptide Ac2-26) can inhibit mast cell degranulation, antigen-induced eotaxin release as well as the accumulation of both neutrophils and eosinophils in a model of rat pleurisy. The purpose of this study was to demonstrate anti-asthmatic effects of Ac2-26 in an asthma model and to explore possible mechanisms involved. METHODS: The effect of Ac2-26 on TH2 cytokine release, eotaxin production, PGD2 levels and the development of pulmonary eosinophilic inflammation was compared with glucocorticoids in an asthmatic rat model. The study was conducted on rats sensitized and challenged with ovalbumin and plethysmography measured airway responsiveness. Bronchoalveolar lavage (BAL) histopathology and the levels of cytokines, chemokines as well as PGD2 were examined. RESULTS: Our results showed that Ac2-26 suppressed the accumulation of eosinophils in airways, reduced IL-4, IL-5, IL-13, PGD2 and eotaxin levels in the BAL fluid, and lowered the expression of CRTH2. Exogenous PGD2 significantly attenuated the biological effects of Ac2-26. CONCLUSION: These results indicated that Ac2-26 exerted broad inhibitory effects on airway inflammation and hyperresponsiveness in a rat model of asthma. Exogenous PGD2 reversed the inhibitory effects of AC2-26 on eosinophil recruitment. Ac2-26 exhibited anti-asthmatic, immunomodulatory activity that was substantially mediated by decreasing PGD2 production and its CRTH2 receptor expression in vivo.

[Protection of oxymatrine against ischemia-reperfusion injury of liver and mechanism thereof: experiment with rats].

OBJECTIVE: To investigate the effects of oxymatrine on protecting the liver against ischemia-reperfusion injury (IRI) and explore the mechanism thereof. METHODS: Thirty male Wistar rats were randomly divided into 3 equal groups: IRI group (2 ml normal saline was injected into the dorsal vein of penis, 30 min later laparotomy was performed, arterial clamp was used to grip the hepatic artery and portal vein for 30 minutes and then removed, the vessels were reperfused for 90 min, and 4 ml blood was collected from the aorta; parts of the liver were resected); oxymatrine group (oxymatrine 40 mg/kg was injected into the dorsal vein of penis, and the other procedures were the same as in the IRI group); and sham operation group (2 ml normal saline was injected into the dorsal vein of penis, laparotomy was performed, 150 min after the injection 4 ml blood was collected from the aorta and parts of the liver were resected). The levels of alanine transaminase (ALT) and aspartate transaminase (AST) were detected. The liver tissues underwent HE staining and TUNEL staining for pathological examination. Suspension of single hepatocytes was prepared to observe the ratio of apoptotic cells and cell cycles by flow cytometry (FCM). Western blotting was used to examine the Fas protein expression. RESULTS: The AST and ALT levels of the IRI group were 1326 U/L +/- 211 U/L and 768 U/L +/- 175 U/L respectively, significantly higher than those of the sham operation group (112 U/L +/- 53 U/L and 55 U/L +/- 17 U/L, both P < 0.05) and those of the oxymatrine group (513 U/L +/- 96 U/L and 352 U/L +/- 72 U/L respectively, both P < 0.01). The liver cells of the sham operation group were normal, those of the IRI group showed remarkable edema and cytoplasm degeneration. TUNEL staining showed remarkably more apoptotic cells in the IRI group. FCM showed that the apoptotic rate of hepatocytes was 42.8% +/- 5.2% in the IRI group, significantly higher than in the oxymatrine group (8.8% +/- 1.8%, P < 0.01), and that the ratio of hepatocytes in G(0)/G(1) stage of the IRI group was 99.2% +/- 1.8%, significantly higher than that of the sham operation group (77.0% +/- 2.1%), and that of the oxymatrine group (87.6% +/- 2.8%) (both P < 0.05); the ratio of hepatocytes in the S stage of the IRI group was 0.52% +/- 0.25%, significantly lower than those of the sham operation group (23.94% +/- 1.84%) and oxymatrine group (12.42% +/- 0.46%) (both P < 0.01). The Fas protein expression was significantly highly in the IRI group than in the oxymatrine group. CONCLUSION: Remarkably reducing the IRI of hepatocytes, oxymatrine has potential to protect the liver against IRI during surgical intervention.