ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01284.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01285.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01286.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01287.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract.PMN function was tested in patients suffering from recurrent infections. In 65 out of 240 patients lack of oxygen radical production or reduced chemo‐tactic activity was found. In most cases the reduction was transient and associated with clinical impairments of the patients. Only a few patients had primary cellular defects. In one of those patients the expression of β2 integrins was reduced, while PMN of the other patients expressed β2 integrins normally. Thus, cellular defects other than the reduced expression of β2 integrins might also result in impaired chemotactic acti

ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01288.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract.Cirrhotic patients with ascites have an unusually high frequency of development of spontaneous bacterial peritonitis. Iron availability is a key factor in bacterial growth and the ability of the host to limit it is associated with resistance to infection. The present study was undertaken to evaluate the influence of iron and transferrin on bacterial growth in ascitic fluid from 25 biopsy‐proven cirrhotic and nine neoplastic carcinomatous patients. No significant differences were found when comparing total ascitic fluid iron between the two groups but ascitic fluid transferrin concentration was significantly lower in cirrhotic (29.26 mg dl‐1SD 29.58) than neoplastic (96.57 mg dl‐1SD 76.01) patients. Moreover, a significant negative correlation was found between bacterial growth and transferrin concentration in ascitic fluid (P = 0.039). When the iron concentration in ascitic fluid was experimentally elevated (50 μg dl‐1or 150 μg dl‐1) we observed a progressive increase in bacterial growth. If transferrin concentration is simultaneously elevated (250 mg dl‐1) this increase does not occur. These findings indicate that the transferrin level is an important factor in the regulation of bacterial growth in ascitic fluid and that the low concentration found in cirrhotic patients could facilitate spontaneous bacteria

ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01289.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract.N‐3 fatty acids were supplied to a 36‐year‐old female patient suffering from ulcerative colitis and severe steroid side‐effects, in a sequence of parenteral and enteral administration. During a moderately active period of disease, 200 ml d‐1fish oil‐derived lipid emulsion (eicosapentaenoic acid [EPA], 4–2 g; docosahexaenoic acid [DHA], 4.2 g) was infused for 9 days, in parallel with rapid tapering of the steroid dose. Disease activity declined rapidly, and the patient was subsequently provided with 16 fish oil capsules per day (EPA, 2.9 g; DHA, 1.9 g) for 2 months. At the end of this period of therapy, severe colitis recurred with intestinal and extraintestinal manifestations. The n‐3 lipid emulsion was then used for intravenous alimentation (29 days, maximum dose 300 ml per day); during this time, marked improvement of the inflammatory bowel disease was noted. During both periods of parenteral n‐3 lipid administration, total plasma EPA and DHA contents increased several‐fold, surpassing that of arachidonic acid; this plasma n‐3 fatty acid enrichment was only maintained to a minor extent during the intermediate period of dietary fish oil supplementation. The intravenously administered EPA‐containing triglycerides were rapidly hydrolyzed, as evidenced by the appearance of substantial quantities of EPA in the plasma free fatty acid fraction. Platelet and neutrophil total membrane content of EPA and DHA as well as n‐3 fatty acid/AA membrane ratios similarly increased during the periods of intravenous n‐3 lipid administration and declined during oral fish oil uptake. In contrast, erythrocyte membrane enrichment in EPA and DHA occurred only after the prolonged (2 month) period of dietary n‐3 lipid supplementation.Ex vivostimulation of neutrophils with A23187 showed progressive increase in 5‐series leukotriene‐ and 5‐HEPE‐generation during both periods of n‐3 lipid infusion, in parallel with the rise of plasma EPA contents. Maximum 5‐series/4‐series leukotriene ratios surpassed 0.25. Similarly, ratios of thromboxane B3/B2liberated fromex vivostimulated platelets surpassed 0.4 during ongoing n‐3 lipid infusion. The profound changes in fatty acid profiles and lipid mediator generation may be related to the reduction in colitis activity observed during the per

ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01290.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract.Erythropoietic protoporphyria (EPP) and porphyria cutanea tarda (PCT) are characterized by skin morbidity, induced by pro‐inflammatory reactive oxygen species generated by the photosensitizing properties of protoporphyrin IX and uroporphyrin I. How these porphyrins exert a toxic effect on the liver in the absence of light is poorly understood. We tested the hypothesis that porphyrins can interference with cellular redox systems, by studying the dark effects of protoporphyrin (PP), haematoporphyrin (HP), deu‐teroporphyrin (DP) and uroporphyrin (UP) on the cellular redox system of phagocytes, and on enzymatic oxyradical generating systems. Both in phagocytic cells and enzymatic systems, a dose‐dependent inhibition of chemiluminescence was observed by all porphyrins added. Catalase and SOD‐like activity of porphyrins was excluded by oxygraph and ferricyto‐chrome c reduction. However, ferrocytochrome c oxidation was inhibited by porphyrins indicating ferrireductase‐like activity. In a Fenton type reaction between H2O2and PP, we could demonstrate the generation of *OH, or an electronically excited por‐phyrin species. No influence on phagocyte chemotaxis, phagocytosis and killing‐capacity was observed. We conclude that porphyrins do interfere with (cellular) redox systems and can both inhibit and enhance oxygen free radical generation, dependent on the type of redox reaction. Porphyrins can thus affect cellular metabolism. Since H2O2and PP both readily dissolve in biological membranes, their interaction in the presence of transition metals may contribute to the toxic dark effects of porphyrins as observed in patients w

ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01291.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract.The abnormal function of the lower oesophageal sphincter in achalasia is likely to be due to impaired nonadrenergic, noncholinergic (NANC) inhibitory input. Since recent studies in animals suggest that nitric oxide (NO) is implicated physiologically in the inhibitory responses of the lower oesophageal sphincter, we have investigated whether the synthesis of NO is altered in the gastro‐oesophageal junction of patients with achalasia. NO synthase activity was investigated in samples of tissue from the gastro‐oesophageal junction obtained during surgery in eight patients with typical achalasia and six non‐achalasic controls who underwent oesophagectomy for reasons other than sphincter dysfunction. The NO synthase activity was determined by the transformation of14C‐L‐arginine into14C‐L‐citrulline in tissue homogenates. In addition, immunohistochemical staining of the tissues was performed using a polyclonal antibody raised against a peptide sequence of rat brain NO synthase. Furthermore, the relaxant response to an exogenous NO donor (sodium nitroprusside, SNP) was measuredin vitroin muscle strips obtained from two patients with achalasia and in two non‐achalasic controls. NO synthase activity was detected in each of the samples obtained from six control patients (0.59 ±0.21 pmol mg‐1min‐1; mean æ). By contrast, none of the samples obtained from the eight patients with achalasia had any detectable NO synthase activity. Immunohistochemical studies confirmed the presence of NO synthase in the myenteric plexus of the gastro‐oesophageal junction of control patients and its absence in achalasia. SNP relaxed muscle strips precontracted with bethanechol in both control samples and those from patients with achalasia. We suggest that the absence of NO synthase in the myenteric plexus of the gastro‐oesophageal junction explains the impaired function of the lower oesophage

ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01292.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Abstract.The relationships between subcutaneous abdominal and femoral fat cell lipolyses, plasma free‐fatty acid (FFA) levels and metabolic variables considered as risk factors for cardiovascular disease (CVD) (plasma glucose, insulin and lipoprotein levels) were investigated in 54 men, aged 36 ± 3 (SD) years, covering a wide range of body fatness values (body mass indices from 19 to 34 kg m‐2). Although there were no consistent relationships between femoral fat cell weight and the metabolic profile, positive and significant associations were found between abdominal fat cell weight and most of the metabolic indices. However, abdominal fat cell lipolysis measured with an α2:‐(clonidine) or a β‐agonist (isoproterenol) was unrelated to metabolic variables. In contrast, femoral fat cell lipolysis measured in the presence of clonidine was positively associated with fasting plasma insulin, cholesterol (CHOL) and apolipoprotein (apo) B levels, as well as with LDL‐CHOL and LDL‐apo B concentrations. No association was found between isoprotere‐nol‐stimulated lipolysis of femoral adipocytes and the metabolic profile. Comparison of two subgroups of men with either low or high femoral residual lipolysis with clonidine revealed that subjects with the lowest femoral α2‐adrenergic component (i.e. the highest residual lipolysis) displayed significant alterations in both plasma lipid‐lipoprotein and glucose‐insulin levels which could be predictive of an increased risk of CVD. Free fatty acid (FFA) levels measured in the fasting state and during an oral glucose tolerance test (OGTT) were positively associated with fasting plasma insulin and triglyceride levels as well as with both glucose and insulin areas measured during the OGTT. However, regional adipose tissue lipolysis measuredin riirowas unrelated to plasma FFA levels. These results support the view that both femoral adipose tissue lipolysis and plasma FFA levels are significant correlates of plasma glucose‐insulin homeostasis and lipoprotein‐lipid levels, in men. However, as adipose tissue lipolysis and plasma FFA are unrelated to each other, they may be associated with risk variables t

ISSN:0014-2972    

DOI:10.1111/j.1365-2362.1993.tb01293.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY