Small vessel vasculitis limited to pleuropulmonary manifestations,possibly induced by endotoxin

AIMS: We investigated a rare case of small vessel vasculitis (SVV) limited to pleuropulmonary manifestations, possibly induced by endotoxin, to determine the activation of immuno-mediated cells and endothelia in the pleuropulmonary circulation. METHODS AND RESULTS: A 44-year-old man with a high fever was X-rayed, revealing bilateral pleural effusion and atelectasis in the chest. His laboratory data were within normal limits except for a high white blood cell count and a high C-reactive protein level. Autoantibodies including anti-neutrophil cytoplasmic antibody were negative. Endotoxin was detected in his sera, but repeated cultures of sputa, urine, blood and the pleural effusion were negative for bacteria. Video-assisted thoracic surgery was performed and lung and parietal pleura specimens were obtained. Histology showed arterioles or small arteries infiltrated by monocytes or neutrophils with fibrinoid necrosis and acute or chronic venulitis. A diagnosis of SVV in the lung and pleura was made. Immunohistochemistry revealed that interleukin (IL)-1beta was expressed in monocytes and vascular cell adhesion molecule (VCAM)-1 on endothelial cells in the vasculitic lesions in the lung. CONCLUSIONS: Endotoxin possibly induced the inflammation in this apparently unique case of pleuropulmonary small vessel vasculitis. Immunohistochemistry revealed the expression of IL-1beta and VCAM-1 which may have caused activation of monocytes and endothelial cells within the vasculitic lesions.     

Markers of Intestinal Permeability Are Rapidly Improved by Alcohol Withdrawal in Patients with Alcohol-Related Liver Disease

Changes in intestinal microbiome and barrier function are critical in the development of alcohol-related liver disease (ALD). Here, we determined the effects of a one-week alcohol withdrawal on parameters of intestinal barrier function in heavy drinkers with ALD in comparison to healthy non-drinkers (controls). In serum samples of 17 controls (m = 10/f = 7) and 37 age-matched ALD patients (m = 26/f = 11) undergoing a one-week alcohol withdrawal, markers of liver health and intestinal barrier function were assessed. Liver damage, e.g., fibrosis and hepatic steatosis, were assessed using FibroScan. Before alcohol withdrawal, markers of liver damage, lipopolysaccharide binding protein (LBP) and overall TLR4/TLR2 ligands in serum were significantly higher in ALD patients than in controls, whereas intestinal fatty acid binding protein (I-FABP) and zonulin protein concentrations in serum were lower. All parameters, with the exception of LBP, were significantly improved after alcohol withdrawal; however, not to the level of controls. Our data suggest that one-week of abstinence improves markers of intestinal barrier function and liver health in ALD patients.     

大鼠酒精性肝病血浆内毒素水平及其对肝脏的损害作用

目的　观察实验性大鼠酒精性肝病时血浆内毒素水平及其在酒精性肝损害中的作用。方法　随机将Wistar大鼠分为乙醇喂养组和葡萄糖喂养对照组。乙醇喂养组大鼠饮水中加入乙醇 (剂量 5～ 1 2 g·kg-1·d-1)喂养 ,对照组饮水中加入相同量的葡萄糖。两组大鼠分别于 4周和 8周活杀取材测定其血浆中内毒素浓度变化及血清中谷丙转氨酶 (ALT)水平变化 ,并在光镜和电镜下观察肝脏的形态学改变。结果　乙醇喂养组大鼠喂养 4周和 8周时血浆内毒素浓度分别为 1 2 9± 2 1 pg/ml和 1 87±3 5pg/ml,明显高于对照组的 48± 9pg/ml和 53± 1 1 pg/ml(P <0 0 5) ;乙醇组血清ALT浓度为 1 1 2± 1 5IU/L和 1 47± 2 2IU/L。也明显高于对照组的 3 1± 1 2IU/L和 3 3± 9IU/L(P <0 0 5)。乙醇组肝组织发生显著的病理变化 ,主要表现为脂肪变性、炎性细胞浸润及细胞坏死。对照组肝组织病理变化不明显。结论　乙醇能诱导大鼠血中内毒素浓度升高 ,造成肝脏损害     

透析膜和内毒素对单个核细胞白细胞介素—1受体拮抗物产生的协同作用

目的：研究不同透析膜和内毒素对尿毒素对尿毒症患者外周血单个核细胞（PBMC）白细胞介素－1受体拮抗物（IL－1Ra）基因转录和IL－1Ra合成的影响。方法：细胞和不同透析膜孵育后采用细胞原位杂交检测mRNA水平,PBMC培养后采用酶联免疫吸附试验法测定细胞IL－1Ra水平。结果：不同析膜孵育后的PBMC在未用内毒素刺激情况下IL－1RamRNA水平有显著判别,但IL－1Ra合成量无差异。其中正常人仅有极微量IL－1Ra合成;内毒素刺激下的PBMC IL－1Ra合成明显明显高于未刺激组,与铜仿膜孵育后的合成量明显高于聚砜膜孵育后和对照组。结论：内毒素和透析膜对正常人和尿毒症患者PBMC的IL－1Ra的合成协同作用。     

败血症弥散性血管内凝血时的白细胞溶血毒性的探讨

分别以凝血活酶和活大肠杆菌诱发家兔DIC,观察到活菌组血浆血红蛋白显著升高。同时WBC、MDA升高,而SOD活性显著下降。另分别以家兔贫白细胞血和富白细胞血与内毒素温育,结果前者溶血轻微,而后者溶血显著,且MDA升高。这表明感染致DIC时,内毒素等物质激活白细胞,可能通过自由基机制表现出溶血毒性。     

Investigation of infection risk and the value of urine endotoxin during extrac orporeal shock wave lithotripsy

目的　探讨体外冲击波碎石 (ESWL)导致机体感染的可能性及测定尿液内毒素的价值和意义。方法　 16 4例上尿路结石病人分成 5组。A组 :4 8例肾结石病人 ,结石 1- 4枚 (直径均≤ 2cm)。B组 :2 4例肾结石病人 ,结石 1- 3枚 (直径均 >2cm)。C组 :2 2例肾结石病人 ,结石 1- 3枚 ,伴 1- 2枚输尿管结石。D组 :51例输尿管结石病人 ,结石 1- 3枚 (直径为 0 5- 1 2cm)。E组 :19例复杂性肾结石病人。除A组外均有不同程度尿流梗阻。ESWL治疗前均无尿路感染。所有患者ESWL治疗前后取血、尿作细菌培养及以鲎试验测内毒素浓度。结果　所有病人ESWL治疗前、后血液内毒素浓度均无显著性变化 ,血液细菌培养均为阴性。B、C和E组ESWL治疗后尿液内毒素均较治疗前显著性升高。A和D组ESWL治疗前后尿液内毒素浓度均无显著性改变。ESWL治疗后B、C和E组尿液细菌培养阳性率较A和D组显著升高 ,或非常显著升高。结论　直径≤ 2cm、对引流系统无明显影响的肾结石或直径 0 5- 1 2cm的输尿管结石 ,ESWL治疗导致泌尿系感染的可能性较小 ;但复杂性、直径 >2cm的肾结石、或肾结石伴输尿管结石 ,即使ESWL治疗前无菌尿症 ,ESWL导致泌尿系感染的可能性大 ,预防性使用抗生素是必要的。另外 ,尿液内毒素测定是诊断ESWL病人泌尿系是否感染的一个     

内毒素对大鼠胰岛细胞凋亡及其意义的研究

目的：探讨内毒素对大鼠胰岛细胞凋亡作用的意义。方法：采用单细胞凝胶电泳和DNA凝胶电泳技术,分析外源NO供体（硝普钠）和LPS对离体胰岛细胞的凋亡及胰岛素合成与分泌的影响。结果：体外试验显示,外源NO明显引起胰岛细胞DNA断裂,出现慧星尾和凋亡梯状带,并呈剂量依赖关系,高浓度NO（60mmol/L,SNP)可引起胰岛细胞DNA随机降解,外源NO强裂抑制葡萄糖刺激β－细胞的胰岛素合成与分泌,LPS离体条件下,对胰岛细胞凋亡作用不明显。结论：LIPS通过整体作用诱导炎症细胞和胰岛细胞iNOS表达,产生NO介导胰岛细胞凋亡,从而抑制胰岛素合成与分泌。     

Evidence for a dilator function of 8-iso prostaglandin F2α in rat pulmonary artery

1. 8-Iso prostaglandin F_2α (8-iso PGF_2α) is one of a series of prostanoids formed independently of the cyclo-oxygenase pathway. It has been shown to be upregulated in many conditions of oxidant stress where its formation is induced by free radical-catalysed actions on arachidonic acid. As 8-iso PGF_2α is formed in vivo in diseases in which oxidant stress is high such as septic shock, we have assessed the relative potency and efficacy of this compound in pulmonary arteries from control and lipopolysaccharide (LPS)-treated rats.
2. Several studies have characterized the contractile actions of 8-iso PGF_2α on various smooth muscle preparations, but its potential dilator actions have not been addressed. Thus these studies examined both the contractile and dilator actions of 8-iso PGF_2α in rat pulmonary artery rings. The thromboxane mimetic U46619, PGE₂ sodium nitroprusside (SNP) and acetyl choline (ACh) were used for comparison. Each prostanoid had to be dissolved in ethanol to a maximum concentration of 1×10⁻² M. At high concentrations, ethanol directly contracted pulmonary vessels. We were therefore limited by the actions of the vehicle such that we were unable to add prostanoids at concentrations higher than 1×10⁻⁴ M. In some cases this meant that maximum responses were not achieved and in these cases the E_max and pD₂ values are apparent estimates.
3. The following rank order of potency was obtained from contractile studies; U46619>8-iso PGF_2α>PGE₂, each prostanoid producing concentration-dependent contractions (10⁻¹⁰3×10⁻⁴ M, 10⁻⁹10⁻⁴ M, 10⁻⁸10⁻⁴ M, respectively). As has been shown previously for other smooth muscle preparations, the thromboxane receptor (TP) antagonist ICI 192605, (1×10⁻⁶, 1×10⁻⁵ and 1×10⁻⁴ M), inhibited the contractions of 8-iso PGF_2α in a concentration-dependent fashion.
4. The nitric oxide synthase inhibitor, N^G-nitro-L-arginine methyl ester (L-NAME; 1×10⁻⁴ M), enhanced the contractile function of both 8-iso PGF_2α and PGE₂, but had no effect on that caused by U46619. Similarly, L-NAME inhibited the dilator function of all agents tested except the exogenous nitric oxide (NO) donor SNP, indicating that PGE₂ and 8-iso PGF_2α like ACh, act through the release of NO. The specificity of the effects of L-NAME were confirmed in studies with the inactive enantiomer D-NAME (1×10⁻⁴ M), which did not affect the contractile or the dilator actions of 8-iso PGF_2α. Furthermore, ICI 192605 enhanced the dilator actions of 8-iso PGF_2α, suggesting that the dilator component of 8-iso PGF_2α was achieved via activation of a non-TP receptor.
5. Isoprostanes may modulate vascular tone by a direct action on TP receptors to cause contraction and via a distinct receptor leading to the release of NO to cause dilatation.

     

Effects of tyrphostins and genistein on the circulatory failure and organ dysfunction caused by endotoxin in the rat: a possible role for protein tyrosine kinase

1. Here we compared the effects of various inhibitors of the activity of protein tyrosine kinase on (i) the expression of the activity of the inducible isoform of nitric oxide (NO) synthase (iNOS) caused by endotoxin (lipopolysaccharide, LPS) in cultured macrophages, (ii) the induction of iNOS and cyclo-oxygenase 2 (COX-2) protein and activity in rats with endotoxaemia, and (iii) the circulatory failure and organ dysfunction caused by LPS in the anaesthetized rat.
2. Activation of murine cultured macrophages with LPS (1 μg ml⁻¹) resulted, within 24 h, in a significant increase in nitrite (an indicator of the formation of NO) in the cell supernatant. This increase in nitrite was attenuated by the tyrphostins AG126, AG556, AG490 or AG1641 or by genistein in a dose-dependent fashion (IC₅₀: ∼15 μM). In contrast, tyrphostin A1 (an analogue of tyrphostin AG126) or daidzein (an analogue of genistein) had no effect on the rise in nitrite caused by LPS.
3. Administration of LPS (E. coli, 10 mg kg⁻¹, i.v.) caused hypotension and a reduction of the pressor responses elicited by noradrenaline (NA, 1 μg kg⁻¹, i.v.). Pretreatment of rats with the tyrphostins AG126, AG490, AG556, AG1641 or A1 attenuated the circulatory failure caused by LPS. Although genistein attenuated the vascular hyporeactivity to NA, it did not affect the hypotension caused by LPS. Daidzein did not affect the circulatory failure caused by LPS.
4. Endotoxaemia for 360 min resulted in rises in the serum levels of (i) urea and creatinine (indicators of renal failure), (ii) alanine aminotransferase (ALT), aspartate aminotransferase (AST), bilirubin and γ-glutamyl transferase (γGT) (indicators of liver injury/dysfunction), lipase (an indicator of pancreatic injury) as well as lactate (an indicator of tissue hypoxia). None of the tyrosine kinase inhibitors tested had a significant effect on the rise in the serum levels of urea, but the tyrphostins AG126, AG556 or A1 significantly attenuated the rises in the serum levels of creatinine caused by LPS. In addition, all tyrphostins and genistein attenuated the liver injury/failure, the pancreatic injury, the hypoglycaemia and the lactic acidosis caused by LPS. In contrast, daidzein did not reduce the organ injury/dysfunction or the lactic acidosis caused by LPS.
5. Injection of LPS resulted (within 90 min) in a substantial increase in the serum level of tumour necrosis factor α (TNFα), which was attenuated by pretreatment of LPS-rats with any of the tyrphostins used. Genistein, but not daidzein, also reduced the rise in the serum levels of TNFα caused by LPS. Endotoxaemia for 6 h also resulted in a substantial increase in the expression of iNOS and COX-2 protein and activity in the lung, which was attenuated by pretreatment of LPS-rats with the tyrphostins AG126, AG556 or genistein, but not by daidzein.
6. Thus, tyrphostins (AG126, AG490, AG556, AG1641 or A1) and genistein, but not daidzein (inactive analogue of genistein), prevent the (i) circulatory failure, (ii) the multiple organ dysfunction (liver and pancreatic dysfunction/injury, lactacidosis, hypoglycaemia), as well as (iii) the induction of iNOS and COX-2 protein and activity in rats with endotoxic shock