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H Louis

Publications and source records attributed to H Louis.

At least 37 records · Page 2Linked to original sources
PubMed1998

Multisystemic production of interleukin 10 limits the severity of acute pancreatitis in mice.

BACKGROUND: Interleukin 10 (IL-10) decreases the severity of experimental acute pancreatitis. The role of endogenous IL-10 in modulating the course of pancreatitis is currently unknown. AIMS: To examine the systemic release of IL-10 and its messenger RNA production in the pancrease, liver, and lungs and analyse the effects of IL-10 neutralisation in caerulein induced acute pancreatitis in mice. METHODS: Acute necrotising pancreatitis was induced by intraperitoneal caerulein. Serum levels of IL-10 and tumour necrosis factor (TNF), and tissue IL-10 and TNF-alpha gene expression were assessed. After injecting control antibody or after blocking the activity of endogenous IL-10 by a specific monoclonal antibody, the severity of acute pancreatitis was assessed in terms of serum enzyme release, histological changes, and systemic and tissue TNF production. RESULTS: In control conditions, serum IL-10 levels increased and correlated with the course of pancreatitis, with a maximal value eight hours after induction. Both IL-10 and TNF-alpha messengers showed a similar course, and were identified in the pancreas, liver, and lungs. Neutralisation of endogenous IL-10 significantly increased the severity of pancreatitis and associated lung injury as well as serum TNF protein levels (+75%) and pancreatic, pulmonary, and hepatic TNF messenger expression (+33%, +29%, +43%, respectively). CONCLUSIONS: In this non-lethal model, systemic release of IL-10 correlates with the course of acute pancreatitis. This anti-inflammatory response parallels the release of TNF and both cytokines are produced multisystemically. Endogenous IL-10 controls TNF-alpha production and plays a protective role in the local and systemic consequences of the disease.

Amylases↗
PubMed1998

Vitronectin expression and interaction with receptors in smooth muscle cells from human atheromatous plaque.

Vitronectin (VN) is a plasma glycoprotein that promotes cell attachment and induces migration of human smooth muscle cells (SMCs) in culture. VN has been observed to accumulate in human atherosclerotic plaques, although its origin and role in atherosclerosis are not yet established. In the present experiments, synthesis of VN by intimal cells and its colocalization with receptors, alphavbeta3 and alphavbeta5, were studied by in situ hybridization and immunohistochemistry on 15 human atherosclerotic plaques from carotid arteries obtained after surgery. Strong VN protein and mRNA expression was observed in the intima and in the media. In the intima, VN mRNA expression was colocalized with SMCs, indicating that these cells produce VN, which may account for its accumulation in atherosclerotic plaques. In SMCs in culture, immunoprecipitation after metabolic labeling demonstrated that human SMCs do synthesize vitronectin. Confocal microscopic examination showed that VN colocalized with its receptors, alphavbeta3 and alphavbeta5, in the atherosclerotic intima. However, the distribution of the VN receptors on SMCs in culture in contact with VN was different. These observations suggest that VN plays various parts in atherogenesis via different SMC membrane receptors.

Arteriosclerosis↗
PubMed1998

[Damage pattern caused by high pressure water jets and high pressure water abrasive jets to the hand].

Water and abrasive water jets have been developed as efficient tools for different purposes in industrial manufacturing, cleaning and dismantling, and--experimentally--in drilling and milling. In contrast to other high pressure techniques, these machines produce power densities up to 250 kW/mm2. In order to assess the range of destruction caused by water as well as abrasive water jets in human hands, cadaveric forelegs of pigs were targeted with constant nozzle geometry and working distance between cadaver and nozzle. Variable parameters investigated included pressure and time of exposure. Reproducible injury patterns were found in the forefoot of the pig, allowing for conclusions to be drawn with respect to damage assessment in the human hand.

Accidents, Occupational↗
PubMed1997

[Spontaneous pneumothorax in young women: possible lymphangioleiomyomatosis].

(Recurrent) pneumothorax developed spontaneously in three women aged 33, 35 and 36 years, two of whom were pregnant. Morbid-anatomical examination of lung biopsy samples in two of them revealed proliferation of smooth muscle cells which through infiltration of pleura, septa, and alveoli had led to loss of pulmonary parenchyma and formation of cystic lesions; the cystic lesions were visible in a CT scan in all three patients. The diagnosis in 2 patients was 'lymphangioleiomyomatosis'; the third patient had anomalies compatible with lymphangioleiomyomatosis, but these were interpreted as tuberous sclerosis because of the presence of renal angiomyolipomas. This disorder occurs exclusively in women in the reproductive age. Treatment consisted in drainage of the pneumothorax, pleurodesis and pleurectomy, with administration of medroxy-progesterone. One year later, the pneumothorax had not recurred.

Adult↗
PubMed1997

Production and role of interleukin-10 in concanavalin A-induced hepatitis in mice.

Experimental T-cell-mediated hepatitis induced by concanavalin A (Con A) involves the production of proinflammatory cytokines. Because interleukin (IL)-10 is a potent anti-inflammatory cytokine derived from macrophages and T cells and is produced within the liver, we investigated the role of IL-10 in modulating the hepatotoxicity and the secretion of cytokines following in vivo injection of Con A. IL-10 is produced early in the serum after Con A challenge. Neutralization of endogenous IL-10 by monoclonal antibodies (mAbs) increases the secretion of tumor necrosis factor alpha (TNF-alpha) (+111%), interferon gamma (IFN-gamma) (+92%), and IL-12 (+730%) 8 hours after Con A injection, and increases the hepatotoxicity, assessed by serum alanine transaminase (ALT) (+174%) measurement and by histology, 24 hours after induction of hepatitis. Conversely, preadministration of recombinant IL-10 reduces the production of these proinflammatory cytokines (-47%, -80%, and -47% for TNF-alpha, IL-12, and IFN-gamma, respectively), and decreases neutrophil infiltration and ALT serum concentration (-74%) 8 hours after Con A challenge. We conclude that IL-10, either endogenously produced or exogenously added, has a hepatoprotective role in Con A-induced hepatitis, through its suppressive property on proinflammatory cytokine production, and that it might be of therapeutic relevance in human liver diseases involving activated T cells.

Animals↗
PubMed1997

Hepatoprotective role of interleukin 10 in galactosamine/lipopolysaccharide mouse liver injury.

BACKGROUND & AIMS: Interleukin (IL)-10 is a potent anti-inflammatory cytokine. Its role in modulating liver injury induced by galactosamine and lipopolysaccharide (Gal/LPS) was investigated. METHODS: The effects of recombinant IL-10 (rIL-10), anti-IL-10 monoclonal antibodies, or gadolinium chloride (GdCl3) pretreatment were studied in mice challenged with Gal/LPS. Tumor necrosis factor (TNF) alpha and IL-10 serum concentrations were measured and liver injury was assessed by alanine aminotransferase (ALT) serum concentrations and by histology. RESULTS: (1) IL-10 is produced early and together with TNF-alpha after Gal/LPS challenge. (2) Anti-IL-10 pretreatment increases TNF-alpha (+443%, P = 0.04), ALT (+160%, P = 0.04) serum levels, and the percentage of severe necrosis compared with control monoclonal antibodies. (3) Administration of rIL-10 30 minutes before Gal/LPS decreases TNF-alpha (-67%, P = 0.02), ALT (-94%, P = 0.01) serum concentrations, and the proportion of severe necrosis. The hepatoprotective effect is still observed when rIL-10 is injected 30 or 120 minutes after Gal/LPS. (4) GdCl3 pretreatment protects against hepatotoxicity, decreases TNF-alpha, but increases IL-10 serum concentrations. CONCLUSIONS: These results indicate that IL-10 protects the liver in the Gal/LPS mouse model. Increased IL-10 and decreased TNF-alpha secretion are potentially involved in the hepatoprotection observed after GdCl3 pretreatment.

Animals↗
PubMed1997

Role of reactive oxygen intermediates in interleukin 10 release after cold liver ischemia and reperfusion in mice.

BACKGROUND & AIMS: Reactive oxygen intermediates and cytokines are key effectors in reperfusion injury after liver ischemia. We hypothesized that reactive oxygen intermediates act as a signal for the release of tumor necrosis factor (TNF) and interleukin 10 (IL-10) after reperfusion of cold-preserved livers. METHODS: An endotoxin-free isolated perfused mouse liver system was designed. Harvested mouse livers were stored at 4 degrees C for 0-28 hours and reperfused for 90 minutes with a warm oxygenated Hank's balanced salt solution (alone or with additives). Cytokine messenger RNA (mRNA) from whole liver was measured by reverse-transcription polymerase chain reaction. Cytokine protein levels and liver injury assessed by alanine aminotransferase levels were evaluated in liver effluent during reperfusion. RESULTS: TNF and IL-10 mRNA and protein concentrations were increased after reperfusion of ischemic livers. N-Acetylcysteine and allopurinol dramatically decreased TNF (-64% and -62%) and IL-10 (-49% and -57%) levels in the effluents, as did an inhibitor of the transcription factor NF-kappaB mobilization (-73% and -76% for TNF and IL-10, respectively). Liver injury was decreased by -40%, -43%, and -54% for the three inhibitors, respectively. CONCLUSIONS: Reactive oxygen intermediates are involved in TNF and IL-10 release after reperfusion of cold-preserved livers.

Animals↗
PubMed1996

Relationship between hepatocyte proliferative activity and liver functional reserve in human cirrhosis.

Hepatocyte proliferative activity is elevated in cirrhotic patients who develop hepatocellular carcinoma (HCC) and decreased in alcohol-induced hepatitis patients with poor outcome. Hepatocyte proliferative activity has not been evaluated in an unselected population of cirrhotic patients regarding the severity of the disease. Forty-six cirrhotic patients (21 alcoholic, 20 viral, and 5 other) were prospectively analyzed by proliferating cell nuclear antigen (PCNA) immunostaining on methanol-fixed, paraffin-embedded liver biopsy specimens. In these conditions, the PCNA-labeling index (PCNA-LI) measures the number of cells in the S-phase and assesses tissue proliferation. The median value of the PCNA-LI for all samples was 4.3% (range, 0%-20.2%). It declined with worsening Child-Pugh score: 9.15% (range, 3.3%-20.2%), 5.3% (range, 1.2%-18%), and 2.4% (range, 0%-4.4%) in Child classes A, B, and C, respectively (P < .05). Using the best cutoff PCNA-LI value to divide cirrhosis into slowly and rapidly proliferating tissue subsets, the PCNA index was independently associated with serum albumin. The probability of survival in patients with a high PCNA-LI ( > 4.4%) was significantly higher than in those with a lower PCNA-LI (0.93 vs. 0.53, at a median follow-up of 153 days; P = .01). In all 6 patients undergoing placement of a transjugular intrahepatic portosystemic shunt (TIPS), the PCNA-LI decreased after the procedure. This early impairment of hepatocyte proliferative activity after TIPS placement might reflect the functional alterations induced by this treatment. In conclusion, hepatocyte proliferative activity assessed by PCNA-LI is increased in cirrhotic patients and decreases with worsening of the disease.

Adult↗
PubMed1976

[Nitrates and nitrites in some commercial delicatessen products].

After a study published in 1974 on nitrate and nitrite contents of 105 cooked ham samples, we undertook in 1975 and 1976 another investigation of 166 samples of various meat products. The results are better than those of 1974: the permissible nitrate and nitrite levels of hams are more respected. But in some other meat products (sausage meat for instance) the levels are sometimes very high. Taking into account the quantity of meat products which can be normally consumed daily, nitrate and nitrite amounts absorbed only by this way are very near, if not exceeding, the daily acceptable intake recommended by the International Committee on Food Additives of the World Health Organization. It seems necessary to reexamine the safety margin left in some cases, to the consumer.

Cooking↗
PubMedDate not supplied

Phenotypic modification of arterial smooth muscle cells in response to medial dissection.

BACKGROUND: In the treatment of peripheral arteries, percutaneous transluminal angioplasty is commonly associated with intimal tears and dissections. OBJECTIVE: To investigate the influence of medial dissection on the remodelling of the vessel wall after balloon injury. METHODS: Aortae were obtained from 14 Fauve de Bourgogne rabbits that had been fed a normal diet. Seven days after the initial pull-back injury, the aortae were examined using morphometric and immunocytochemical methods. RESULTS: Eight rabbits (57%) had a tear that extended into the media. Morphometric measurements showed that the intima was significantly thinner when there was a medial dissection [(18.3 +/- 6.9) x 10(-3) versus (39.1 +/- 3.5) x 10(-3) mm without dissection, P < 0.001]. In the media of injured vessels, medial dissection was associated with a greater accumulation of extracellular matrix proteins (50.5 +/- 9.7 versus 12.4 +/- 2.2% of the surface area), a marked reduction in alpha-smooth muscle actin content (36.6 +/- 5.4 versus 47.4 +/- 7.5% of the surface area), a higher expression of a smooth muscle activation antigen (21.2 +/- 5.7 versus 8.9 +/- 1.5% of the 2P1A2-immunostained surface area) and an increase in the number of medial proliferating cell nuclear antigen-positive nuclei (8.2 versus 1.2% of labelled nuclei). CONCLUSION: These observations indicated that mechanical injury of the arterial wall induces a phenotypic activation of medial smooth muscle cells. In the case of acute distension, the response of the smooth muscle cells in the media was mainly responsible for wound healing in the presence of medial dissection; moreover, acute distension induced a significant higher state of activation and a medial repairing that could prevent migration towards the intimal space.

Actins↗
PubMedDate not supplied

Long-term terlipressin administration improves renal function in cirrhotic patients with type 1 hepatorenal syndrome: a pilot study.

BACKGROUND: Hepatorenal syndrome (HRS) is a severe complication of liver cirrhosis. Recently, ornipressin, a potent splanchnic vasoconstrictor, was reported to improve renal function in patients with HRS. However, this treatment is associated with a high incidence of vascular complications. Terlipressin is thought to be as effective as ornipressin with less systemic complications. AIMS: To evaluate the effectiveness and safety of terlipressin administration in cirrhotic patients with type 1 HRS. PATIENTS: Twelve consecutive patients fulfilling HRS criteria of the International Ascites Club were included in the study. Median plasma creatinine and sodium, urine volume and sodium before treatment were 3.4 mg% (2.5-4.0); 127 mEq/l (124-130), 500 ml/24 h (100-1031) and 7 mEq/24 h (1-17). METHODS: Terlipressin was administered i.v. 2 mg bid in 8 patients and tid in 4 others for at least one week and up to 2 months. RESULTS: After one week of treatment median plasma creatinine decreased to 1.8 mg% (1.3-2.1) together with an increase in urine volume, sodium excretion, creatinine and free-water clearance. Three patients underwent successful liver transplantation with a near normal renal function after 34, 36 and 111 days. The 9 other patients died during follow-up (4 from sepsis, 2 from digestive bleeding and 3 from liver failure). No ischaemic complications were encountered during the treatment. CONCLUSIONS: Long-term terlipressin administration is safe and effective to control type 1 HRS. However, it does not cure the underlying disease and therefore, may only be considered as a bridge to a definitive treatment as liver transplantation.

Adult↗