bluuebunny/crossref_metadata_2025 huggingface dataset:
Complexes between proteinase 3, α1‐antitrypsin and proteinase 3 anti‐neutrophil cytoplasm autoantibodies: a comparison between α1‐antitrypsin PiZ allele carriers and non‐carriers with Wegener's granulomatosis
Authors: Baslund B. , Szpirt W. , Eriksson S. , Elzouki A.‐N. , Wiik A. , Wieslander J. , Petersen J.
Published: November 2003

To test the hypothesis that anti‐neutrophil cytoplasm autoantibodies (ANCAs) interfere with the functions of proteinase 3 (PR3) (the Wegener autoantigen) and α1‐antitrypsin (α1AT), complexes of PR3/α1AT and PR3/PR3‐ANCA‐IgG were assayed. Plasma samples were obtained from 44 patients with Wegener's granulomatosis (WG): 34 had active disease (88% ANCA positive) whereas 10 patients were in remission (20% ANCA positive). Plasma samples from 14 of the patients with active disease were also available at the time of remission. The complexes of PR3/α1AT and PR3/PR3‐ANCA‐IgG were detected by capture enzyme‐linked immunoassays (ELISAs). α1AT deficiency was evaluated by determining PiZ alleles by ELISA. Eight (18%) of the patients were PiZ positive. The frequency of this α1‐antitrypsin phenotype in the Scandinavian population is 4.7% (P < 0.001). The median PR3/α1AT complex level in the PiZ‐positive group with active disease (n = 5) was similar to the level in the PiZ‐negative group with active disease. During remission the median level for the PR3/α1AT complex was significantly higher than in the acute group (P < 0.001) including both PiZ‐positive and PiZ‐negative patients. No difference between PiZ positivity and PiZ negativity could be found in the remission group. PR3/PR3‐ANCA‐IgG complexes were found in patients with acute disease as well as in patients in remission, in almost equal frequency. This complex was also present in 13/18 ANCA‐negative samples from patients in remission. Finally, purified IgG fractions from WG patients were examined for their capacity to inhibit binding between PR3 and α1AT. An effect on the binding between PR3 and α1AT by PR3‐ANCA could not be demonstrated. Thus, our results do not support the hypothesis that PR3‐ANCA interferes with the binding between PR3 and α1AT. However, the high prevalence of the PiZ alleles among WG patients suggests that an imbalance between proteinases and α1AT may be of importance in this disease. The clinical usefulness of both the PR3/α1AT and the PR3/PR3‐ANCA‐IgG complexes and the possible influence on ANCA detection need to be examined in prospective longitudinal studies.
Human corticotropin‐releasing hormone and thyrotropin‐releasing hormone modulate the hypercapnic ventilatory response in humans
Authors: SCHULZ R. , NINK M. , WERNER G. S. , ANDREAS S. , KREUZER H. , BEYER J. , LEHNERT H.
Published: November 2003

Human corticotropin‐releasing hormone (hCRH) and thyrotropin‐releasing hormone (TRH) are known to stimulate ventilation after i.v. administration in humans. In a placebo‐controlled, single‐blind study we aimed to clarify if both peptides act by altering central chemosensitivity. Two subsequent CO2‐rebreathing tests were performed in healthy young volunteers. During the first test 0.9% NaCl was given i.v.; during the second test 200 μg of hCRH (n = 12) or 400 μg of TRH (n = 6) was administered i.v.. Nine subjects received 0.9% NaCl i.v. during both rebreathing manoeuvres. The CO2–response curves for the two tests were compared within the same subject. In the hCRH group a marked parallel shift of the CO2–response curve to the left was observed after hCRH (P < 0.01). The same effect occurred following TRH but was less striking (P = 0.05). hCRH and TRH caused a reduction in the CO2 threshold. The CO2–response curves in the control group were nearly identical. The results indicate an additive effect of both releasing hormones on the hypercapnic ventilatory response in humans, presumably independent of central chemosensitivity.
Kinetics of primary bile acids in patients after orthotopic liver transplantation
Authors: SAUER P. , RUDOLPH G. , ENDELE R. , SENN M. , THEILMANN L. , OTTO G. , STREMMEL W. , STIEHL A.
Published: November 2003

Administration of cyclosporin A (CsA) may induce cholestasis, and this effect has been attributed to impaired hepatocellular uptake, transport, secretion and intestinal absorption of bile acids. Disturbances of the enterohepatic circulation may affect metabolism of bile acids. To test whether liver transplantation and treatment with CsA alters pool sizes or synthesis and turnover rates, we determined kinetics of primary bile acids in patients after orthotopic liver transplantation on CsA. Two male and four female patients were studied 6–20 months after transplantation. They had no overt signs of cholestasis, graft dysfunction or rejection. Kinetics of cholic acid (CA) and chenodeoxycholic acid (CDCA) were simultaneously determined after oral administration of [24‐13C]‐CA and [24‐13C]‐CDCA on the basis of isotope dilution in a single pool of bile acids. Ten healthy volunteers served as controls. After orthotopic liver transplantation, pool sizes, fractional turnover rates and synthesis rates of both primary bile acids, CA and CDCA were not significantly different from control subjects. In spite of the known interference of CsA with the enterohepatic circulation of bile acids, in the majority of patients after orthotopic liver transplantation without cholestasis, graft dysfunction or rejection, treatment with CsA does not disturb kinetics of primary bile acids.
Influence of insulin on cholesterol removal from macrophages and cholesterol ester uptake by HepG2 cells
Authors: WYBRAŃSKA I. , BACZYŃSKA E. , CIAŁOWICZ U. , POLUS A. , DEMBIŃSKA‐KIEĆ A.
Published: November 2003

The fact that an increased blood insulin level is observed in patients with coronary artery disease (CAD) confirms the hypothesis that insulin promotes the development of atherosclerosis. The low high‐density lipoprotein (HDL) concentration observed in such patients may contribute to alteration in reverse cholesterol transport and promote the accumulation of sterols in vascular tissue. We examined the effect of insulin (20−1000μUmL−1) on cholesterol efflux into HDL3 particles from human blood monocyte/macrophages and rat peritoneal macrophages preloaded with labelled cholesterol esters, and the influence of insulin on the accumulation of sterols by rat liver cells and HepG2 cell line in vitro models. Insulin at concentrations up to 250μUmL−1 inhibited the efflux of cholesterol from rat macrophages and promoted high uptake of sterols by both types of hepatic cells. Pharmacological concentrations higher than 250μU mL−1 exerted the opposite effect. In the case of human macrophages, an insulin concentration of 20μUmL−1 increased cholesterol removal, whereas 100−200μU mL−1 insulin inhibited cholesterol removal from cells, and very high concentrations (>350μUmL−1) again increased cholesterol removal. We have shown that insulin excess counteracts the beneficial effects of HDL in removing cellular cholesterol and, therefore, may promote development of atherogenesis.
Flow cytometric analysis of platelet activation markers CD62P and CD63 in patients with coronary artery disease
Authors: MURAKAMI T. , KOMIYAMA Y. , MASUDA M. , KIDO H. , NOMURA S. , FUKUHARA S. , KARAKAWA M. , IWASAKA T. , TAKAHASHI H.
Published: November 2003

We investigated whether platelet activation could be quantitatively detected in patients with coronary artery disease using flow cytometric analysis of the expression of CD62P and CD63, which are activation‐specific antigens on the platelet surface. Platelet samples were obtained from 16 healthy control subjects and 65 patients, of whom 25 had angiographically normal coronary arteries and 40 had at least one major coronary artery stenosis (≥ 50% narrowing). In both patient groups, CD62P expression was significantly higher than in the control group, but the difference between the two patient groups was not significant. In contrast, CD63 expression did not differ among the three groups. We also compared expression of these antigens after stratifying the patients according to the number of significant coronary artery stenoses. Patients with three‐vessel disease had significantly increased CD62P and CD63 expression compared with the other subgroups. Our findings indicate that platelet activation occurs in patients with severe coronary artery stenosis.
The effects of hyperinsulinaemia on myocardial mass, blood pressure regulation and central haemodynamics in rats
Authors: HOLMÄ NG A. , YOSHIDA N. , JENNISCHE E. , WALDENSTRÖM A. , BJÖRNTORP P.
Published: November 2003

Left ventricular hypertrophy is a condition with high mortality. An association with insulin resistance and hyperinsulinaemia has recently been suggested. The aim of this study was to examine the effects of isolated hyperinsulinaemia on cardiac weight and haemodynamic regulation. Rats were exposed to hyperinsulinaemia for 7 weeks after adrenalectomy with corticosterone substitution and continuous infusion of propranolol to control counter‐regulatory mechanism (n=15) (AIP group). Hypoglycaemia was prevented by glucose in the drinking water. Hyperinsulinaemic (AIP) rats were heavier and had increased relative masses of the myocardium (left ventricle 17% and right ventricle 20%), kidneys and adipose tissues in comparison with normoinsulinaemic adrenalectomized, corticosterone‐ and propranolol‐treated controls (AP) (n=10). Blood pressure in the insulin‐exposed animals, measured weekly by the tail‐cuff method in conscious rats, was not different from (AP) controls over 5 weeks, but increased in the sixth week. At the end of the seventh experimental week, blood pressure measured intra‐arterially was also found to be elevated. Heart rate was not changed but total peripheral resistance was about twice that of controls (P<0.001). Cardiac output and stroke volume was 30–40% lower in the AIP rats (P<0.05). It is concluded that exposure to elevated insulin levels with control of counter‐regulating mechanisms from β‐adrenergic mechanisms and adrenals is not immediately followed by blood pressure elevation. It is, therefore, suggested that early onset of blood pressure elevation after insulin exposure might be caused by insulin counter‐regulatory events, causing both insulin resistance and blood pressure elevation. The long‐term adaptations may involve a direct influence by insulin as a ‘trophic factor’ on myocardial and on peripheral resistance vessels, followed by increased blood pressure, decreased cardiac output and stroke volume.
Identification of steroid receptors in human adipose tissue
Authors: PEDERSEN S. B. , FUGLSIG S. , SJØGREN P. , RICHELSEN B.
Published: November 2003

Steroids have the ability to alter adipose tissue distribution. Controversy exists as to whether these effects of sex hormones (oestrogen, progesterone and testosterone) on human adipose tissue are indirect or direct, as only very few studies have focused on steroid receptor status in human adipose tissue. In the present study, we reinvestigated steroid receptor status in human mature adipose tissue and human preadipocytes. Oestrogen, glucocorticoid and androgen receptors were found in human mature adipocytes from both women and men. The receptors were detected by ligand binding. Furthermore, the existence of the receptors was confirmed by demonstrating that adipocytes contained mRNA encoding the receptors. cDNA was generated using reverse transcriptase (RT) followed by polymerase chain reaction (PCR) amplification using specific primers (RT–PCR) for the specific steroid receptors. Adipocytes did not contain mRNA encoding the progesterone receptor (PR), and no progesterone binding was detectable in human adipocytes. Human preadipocytes contained glucocorticoid receptor (GR) mRNA and androgen receptor (AR) mRNA, whereas we were unable to detect oestrogen receptor (ER) mRNA and progesterone mRNA in human preadipocytes. In conclusion, oestrogen glucocorticoid and androgen receptors are present in mature adipocytes from subjects of both sexes, whereas adipocytes do not contain progesterone receptors. In preadipocytes, only glucocorticoid receptors and androgen receptors are present, whereas oestrogen receptors and progesterone receptors are not present.
Effect of hormone replacement therapy on the susceptibility of low‐density lipoprotein to oxidation among postmenopausal hypercholesterolaemic women
Authors: NENSETER M. S. , VOLDEN V. , BERG T. , DREVON C. A. , OSE L. , TONSTAD S.
Published: November 2003

The effect of sequential combined hormone replacement therapy on the susceptibility of low‐density lipoprotein to oxidative modification was investigated in a double‐blind, randomized placebo‐controlled study. Hypercholesterolaemic, postmenopausal women were supplemented with 17β‐oestradiol and norethisterone acetate (n=13 subjects) or placebo capsules (n=15 subjects) for 12 weeks. They were instructed to follow the American Heart Association step one diet. Low‐density lipoprotein, isolated before and after treatment, was subjected to copper‐catalysed lipid peroxidation. There were no significant differences between low‐density lipoprotein from the hormone replacement therapy and placebo groups, as assessed by measuring the lag time for formation of conjugated dienes, the rate of formation and the amount of conjugated dienes formed, the amount of lipid peroxides generated, and the relative electrophoretic mobility at baseline and after treatment. Dietary records showed that the subjects were consuming similar amounts of fat and vitamins. No major differences were found in the fatty acid pattern of low‐density lipoprotein from the two groups. In conclusion, the results indicated that hormone replacement therapy with 17β‐oestradiol sequentially combined with norethisterone acetate in non‐smoking, hypercholesterolaemic, postmenopausal women has no protective effect on the susceptibility of low‐density lipoprotein to copper‐catalysed modification in vitro.
Diadenosine polyphosphates induce transplasma membrane calcium influx in cultured glomerular mesangial cells
Authors: TEPEL M. , HEIDENREICH S. , SCHLÜTER H. , BEINLICH A. , NOFER J.‐R. , WALTER M. , ASSMANN G. , ZIDEK W.
Published: November 2003

The effects of diadenosine tetraphosphate (AP4A) diadenosine pentaphosphate (AP5A) and diadenosine hexaphosphate (AP6A) on the cytosolic‐free calcium concentration ([Ca2+]i) were evaluated in cultured rat glomerular mesangial cells (MCs) using the fluorescent dye technique. The addition of 10 μmol L−1 AP4A, AP5A or AP6A significantly increased [Ca2+]i in MCs by 57±9 nmol L−1n=17; P<0.001), 76±27 nmol L−1 (n=9; P<0.001) or 65±12 nmol L−1 (n=18; P<0.01) respectively. In the absence of extracellular calcium, there was no significant change in [Ca2+]i in MCs after administration of diadenosine polyphosphates, indicating that these agents induce transplasma membrane Ca2+ influx. AP6A significantly enhanced the angiotensin II‐induced changes in [Ca2+]i in MCs. The AP5A‐induced transplasma membrane Ca2+ influx was inhibited by the P2 purinoceptor blockers suramin and pyridoxal‐phosphate‐6‐azophenyl‐2′,4′‐disulphonic acid (PPADS), but was not affected by the adenosine A1 receptor blocker 8‐cyclopentyl‐1.3‐dipropylzanthine (CPDPX). Adenosine triphosphate (ATP) and adenosine 5′‐O‐(3‐thio)triphosphate (ATP‐γS) increased [Ca2+]i in MCs, whereas α,β‐methylene ATP had no effect on [Ca2+]i in MCs. Measurements of diacylglycerol and phosphatidic acid showed that AP5A and AP6A also stimulated phospholipase C, but had no effect on phospholipase D. The inhibition of phosphatidylcholine‐specific phospholipase C significantly reduced the AP5A‐induced [Ca2+]i increase. In summary, diadenosine polyphosphates induce Ca2+ influx through P2 purinoceptors and may be involved in the local regulation of vascular resistance evoked by the Ca2+‐dependent contractile response of mesangial cells.
Phyllanthus amarus down‐regulates hepatitis B virus mRNA transcription and replication
Authors: LEE C.‐D. , OTT M. , THYAGARAJAN S. P. , SHAFRITZ D. A. , BURK R. D. , GUPTA S.
Published: November 2003

The Phyllanthus amarus plant shows potential for treating hepatitis B virus. To define the mechanism of action of P. amarus, we used HepG2 2.2.15 cells, which support hepatitis B virus replication. P. amarus inhibited hepatitis B virus polymerase activity, decreased episomal hepatitis B virus DNA content and suppressed virus release into culture medium. To examine transcriptional control mechanisms, we used G26 hepatitis B virus transgenic mice, which produce serum HBsAg but neither HBcAg nor virion particles. When P. amarus was administered to transgenic mice, hepatic HBsAg mRNA levels decreased, indicating transcriptional or post‐transcriptional down‐regulation of the transgene. Increase in hepatitis B virus mRNA expression after stimulation of the glucocorticoid responsive element was also suppressed by P. amarus, suggesting involvement of the hepatitis B virus enhancer in this response. Disruption by P. amarus of hepatitis B virus polymerase activity, mRNA transcription and replication supports its role as an antiviral agent.
Molecular analysis of the T‐cell receptor β‐chain repertoire in early rheumatoid arthritis: heterogeneous TCRBV gene usage with shared amino acid profiles in CDR3 regions of T lymphocytes in multiple synovial tissue needle biopsies from the same joint
Authors: STRUYK L. , HAWES G. E. , MIKKERS H. M. M. , TAK P.‐P. , BREEDVELD F. C. , VAN DEN ELSEN P. J.
Published: November 2003

To gain insight into the nature of the immune response with respect to accumulation and composition of the T‐cell receptor (TCR) repertoire in synovial tissue in rheumatoid arthritis (RA), we have determined the nucleotide sequence of TCRBV regions transcribed by T lymphocytes derived from synovial tissue. Synovial tissue was obtained by needle biopsies from three different sites of the same joint in two early RA patients. We found that the TCRBV region repertoire among synovial tissue‐infiltrating mononuclear cells was heterogeneous when the different biopsies taken from each patient were compared. However, DNA sequence analysis of TCRBV rearrangements of synovial T lymphocytes showed conserved amino acid usage profiles in the CDR3 domains of different TCRBV regions, which exhibited an individual specific character. These CDR3 motifs were not present in paired samples of peripheral blood. The existence of homologous CDR3 amino acid profiles within the TCRBV regions derived from synovial tissue is indicative of an antigen‐driven immune response.
Different effects of continuous oestrogen–progestin and transdermal oestrogen with cyclic progestin regimens on low‐density lipoprotein subclasses
Authors: TILLY‐KIESI M. , LAPPI M. , PUOLAKKA J. , LUOTOLA H. , PYÖRÄLÄ T. , TASKINEN M.‐R.
Published: November 2003

Seventy‐five postmenopausal women were randomly allocated to receive either continuous oral 17β‐oestradiol 2mgday−1 and norethisterone acetate 1 mg day−1 (E2/NETA) or transdermal treatment consisting of 28‐day cycles with patches delivering 17β‐oestradiol 50μgday−1 combined with oral cyclic medroxyprogesterone acetate 10mgday−1, on days 17–28 (E2/MPA). At baseline, the plasma lipid and lipoprotein concentrations, composition and concentrations of low‐density lipoprotein (LDL) subclasses (LDL1, LDL2 and LDL3) isolated by density‐gradient ultracentrifugation were similar in the two groups. The post‐heparin plasma hepatic lipase activity (HL) correlated inversely with the percentage of total LDL found in LDL1 (buoyant LDL) and directly with the percentage of LDL found in LDL3 (dense LDL). After 12 months of hormone replacement therapy (HRT), the total and LDL‐cholesterol concentration of the E2/NETA group decreased by 14% and 17% respectively (P<0.001), while in the E2/MPA group these parameters remained unchanged. The lowering of LDL‐cholesterol in the E2/NETA group was a consequence of a significant reduction of the large, buoyant LDL particles (LDL1) from 103mgdL−1 to 60mgdl−1 (P<0.001) and of a decrease of cholesterol content of LDL particles in the major LDL subclass, LDL2. In the E2/MPA group, the concentration of LDL1 decreased, but less than in the oral group. In both groups, a significant increase in the concentration of the LDL3 subclass was observed, indicating an overall shift to denser LDL particles. After 12 months, the post‐heparin plasma HL activity decreased only in the E2/NETA group (by 12%). The inverse correlation between post‐heparin plasma HL activity and LDL1 persisted in both groups, but the direct correlation between HL and LDL3 vanished in the E2/NETA group and subsided in the E2/MPA group. Our results indicate that HRT has multiple effects on LDL subclasses and suggest that these changes cannot be explained by changes in HL activity.
To determine the effects of ultraviolet light, natural light and ionizing radiation on pyridinium cross‐links in bone and urine using high‐performance liquid chromatography
Authors: COLWELL A. , HAMER A. , BLUMSOHN A. , EASTELL R.
Published: November 2003

The aims of the study were to characterize the denaturation of urinary free and conjugated pyridinoline (Pyr) and deoxypyridinoline (Dpyr) on exposure to ultraviolet (UV) and natural light at different pH levels and to study the effects of X‐ and γ‐irradiation on Pyr and Dpyr in urine and in the mineralized and non‐mineralized compartments of human bone. Urine samples from six normal subjects, adjusted to pH 3.0, 7.0 and 9.0, were exposed to UV light for up to 3 days. Urine collections (2 mL and 24 h) from three subjects, pH adjusted to 1.0, 2.0, 3.0, 4.0 and 5.0, were exposed to natural light for up to 1 day. Urine samples and bone slices from seven human cadaveric femurs were irradiated with increasing doses of X‐rays (0–100 Gy) and high‐dose γ‐radiation (28kGy). Mineralized and non‐mineralized bone were separated using a modification of a published method employing heat denaturation followed by trypsin hydrolysis and analysed for Pyr, Dpyr and hydroxyproline (Hypro). The rate of UV photolysis of urinary Pyr and Dpyr increased with pH and was faster in the free fraction (after 3 days’ exposure: free Pyr and Dpyr at pH 7.0 vs. 9.0, P<0.05, conjugated pH 3.0 vs. 9.0, P<0.05). Exposure to natural light for 3 h did not significantly decrease urinary Pyr and Dpyr in either sample collections, but levels were reduced in the 2‐mL aliquots after exposure for 1 day (P<0.05). X‐irradiation of urine and bone did not affect Pyr and Dpyr. Pyr content was similar in both bone compartments (Pyr/Hypro=0.12±0.004), but Dpyr was higher in the non‐mineralized compartment (Dpyr/Hypro=0.047±0.002 vs. 0.038±0.002, P<0.001). UV light and γ‐irradiation result in denaturation of pyridinium cross‐links in urine. These cross‐links are present in both the mineralized and non‐mineralized bone compartments but are not affected by the doses of γ‐irradiation that denature these cross‐links in urine.
Helicobacter pylori and proteolytic activity
Authors: NILIUS M. , PUGLIESE M. , MALFERTHEINER P.
Published: November 2003

Protease activity of 10 different H. pylori strains, purified marker proteases and protease‐positive reference bacteria (Klebsiella ozaenae, Serratia marcescens) were tested against bovine haemoglobin, porcine mucin, bovine serum albumin, gelatin and casein as substrates. After incubation in development buffer and subsequent staining with Coomassie blue, protease activity bands were demonstrated as transparent spots after polyacrylamide gel electrophoresis (PAGE) on gels with incorporated substrate. Presence of protease activity was investigated in a wide pH range (pH 2.0–9.0). Although marker proteases (0.15–0.2μg per slot) as well as protease‐positive bacteria (2–30μg per slot) clearly showed proteolytic activity in gels containing 0.1–0.2% proteinmL−1, no proteolytic activity was demonstrated in any of the H. pylori strains tested. This finding indicates that H. pylori does not possess significant protease activity, as this would have been detected by this sensitive method.
Effects of isolated limb perfusion with tumour necrosis factor‐alpha on the function of monocytes and T lymphocytes in patients with cancer
Authors: STAM T. C. , JONGEN‐LAVRENCIC M. , EGGERMONT A. M. M. , SWAAK A. J. G.
Published: November 2003

The objective of the present study was to investigate the effects of isolated limb perfusion (ILP) with tumour necrosis factor alpha (TNF‐α) and melphalan in patients with cancer on, first, plasma levels of cytokines, second, systemic monocyte and T‐lymphocyte distribution and, third, the ability of mononuclear cells to produce cytokines upon stimulation in vitro. Six patients undergoing an ILP were entered into the study (group 1). In addition, patients undergoing a major surgical operation (group 2), minor operation (group 3) as well as healthy volunteers (group 4) were included as control groups. Sensitive enzyme‐linked immunosorbent assays (ELISAs) were used to measure TNF‐α and interleukin‐6 (IL‐6) plasma levels at various time points during and after operation. Furthermore, the percentage of monocytes and T lymphocytes was determined in all studied groups using a FACScan. In addition, cytokine production upon stimulation with lipopolysaccharide (LPS) and a combination of anti‐CD3/anti‐CD28 monoclonal antibodies in whole‐blood cultures was investigated. Increased plasma levels of TNF‐α and IL‐6 in patients undergoing ILP was observed, but only IL‐6 appeared to be increased in patients treated with a major operation. No significant fluctuations were found in the other groups studied. Concerning the number of monocytes, a significant decrease was observed only in patients treated with ILP. Furthermore, a decreased production of TNF‐α, IL‐6 and IL‐8 upon various types of stimulation in vitro was found in those patients, but also after a major operation. In conclusion, the results of the present study show increased plasma levels of cytokines in patients treated with ILP and major operation. Furthermore, a decrease in numbers of monocytes in the circulation and the ability of mononuclear cells to produce cytokines in vitro may be induced by administration of TNF‐α in ILP. Although similar results were found in patients treated with major operation, the underlying mechanisms of this phenomenon remain to be elucidated.
Screening and characterization of specific anti‐lipopolysaccharide antibodies in Belgian blood donors by enzyme‐linked immunosorbent assays
Authors: NYS M. , LAUB R. , DAMAS P. , SONDAG D. , GOETHALS T. , JAMAER D. , JOASSIN L. , LAMY M.
Published: November 2003

The goal of this project was to find and collect high concentrations of endotoxin‐specific antibodies for therapeutic IgG‐ or IgM‐enriched preparations. Various enzyme‐linked immunosorbent assays (ELISAs) were developed to perform longitudinal studies of the serological response to a large panel of smooth and rough purified lipopolysaccharide (LPS) extracts in a population of healthy blood donors. To accomplish this, 1612 human serum samples from volunteer blood donors collected by seven different blood banks in Belgium were screened and specific IgM and IgG activities were measured. Approximately 17% of the donors had anti‐LPS concentrations higher than 40 mg L−1. Of these, 10.9% had anti‐smooth LPS antibodies, 3.7% had anti‐rough LPS antibodies and 2.8% were found to be positive towards both types of LPS. The mean anti‐LPS antibody concentration was 8 mg L−1 for rough LPS and 14 mg L−1 for smooth LPS. Age‐ and sex‐related distributions of the activities indicated that the greatest prevalence of high anti‐LPS concentration was in women aged 40–49 years and in men older than 60 years. Differential absorption experiments showed that the pooled serum of selected blood donors contained a mixture of specific and cross‐reacting antibodies. We detected predominantly anti‐LPS activities due to the IgG1 and IgG2 subclasses. The range of specificities to different LPS was increased by the pooling of selected sera. It was concluded that pools of naturally occurring specific anti‐LPS immunoglobulin antibodies may be obtained in Belgium by screening blood donors using ELISAs that we have developed.
Gastric mucosal phospholipids in dogs with familial stomatocytosis−hypertrophic gastritis
Authors: RENOOIJ W. , SCHMITZ M. G. J. , VAN GAAL P. J. , SLAPPENDEL R. J.
Published: November 2003

In dogs, hypertrophic gastritis, which resembles Ménétrier's disease in man, has been demonstrated to be part of a hereditary syndrome called familial stomatocytosis–hypertrophic gastritis. In addition to hypertrophic gastritis, affected dogs exhibit abnormal blood phospholipid composition. Phospholipids may play a role in maintaining gastric mucosal integrity, and this may be compromised in gastritis. The question arises whether the differences in blood phospholipids may result from a disorder that might also be revealed in the composition of gastric mucosal phospholipids. We analysed the phospholipid composition of gastric mucosa from four dogs with familial stomatocytosis–hypertrophic gastritis. The general phospholipid composition and the molecular composition of phosphatidylcholine from mucosal tissue in the corpus of the stomach where hypertrophic gastritis was evident were not different from that of the antrum, where the tissue was normal. These results do not corroborate a relation between the gastric mucosal phospholipid composition and hypertrophic gastritis.
Changes in biliary lipid output after interruption of pravastatin treatment in humans
Authors: HILLEBRANT C.‐G. , ERIKSSON M. , NYBERG B. , EINARSSON K.
Published: November 2003

The use of 3‐hydroxy‐3‐methylglutaryl coenzyme A (HMG‐CoA) reductase inhibitors (e.g. pravastatin) has gradually increased in the treatment of hypercholesterolaemia. By inhibiting HMG‐CoA reductase (the rate‐limiting enzyme in cholesterol synthesis) activity, cholesterol synthesis in the liver is reduced and the plasma level of cholesterol, especially low‐density lipoprotein (LDL)‐cholesterol, is substantially lowered. Simultaneously, inhibition of HMG CoA reductase activity is associated with increased synthesis and accumulation of larger amounts of HMG CoA reductase enzyme protein. The main purpose of this study was to determine if the cessation of pravastatin treatment causes a rapid increase in the synthesis and biliary secretion of cholesterol, a condition which might lead to a temporarily increased cholesterol saturation of bile. Nine patients undergoing surgery for stones in the common bile duct were fitted with T‐tubes in the common bile duct peroperatively; the side arm of the T‐tube was left open postoperatively, creating a biliary fistula. All patients were given 6 days’ treatment with pravastatin (20 mg b.i.d.) following the operation. Bile was collected from the T‐tube, in 12‐h fractions during this period and for another 3 days after termination of the treatment. Plasma levels of lipoproteins and lathosterol — reflecting cholesterol synthesis — were determined on several occasions. After cessation of pravastatin treatment, the plasma levels of total cholesterol and LDL‐cholesterol increased by 21% and 33% respectively. High‐density lipoprotein (HDL)‐cholesterol did not change. The plasma level of lathosterol was increased two‐ to fourfold. Outputs of bile acids and phospholipids were significantly increased (23% and 10% respectively) after termination of treatment, whereas the output of cholesterol was not significantly changed. Cholesterol saturation was reduced by 20%, from 175±37% to 140±19%, but this change was not significant. The results indicate that, with the present experimental model (biliary diversion), the synthesis and biliary secretion of bile acids seem to be largely dependent on the de novo synthesis of cholesterol in the liver, whereas the biliary output of cholesterol is not.
Development and exacerbation of oral lichen planus during and after interferon therapy for hepatitis C
Authors: NAGAO Y. , SATA M. , IDE T. , SUZUKI H. , TANIKAWA K. , ITOH K. , KAMEYAMA T.
Published: November 2003

Oral lichen planus (OLP) is frequently seen in patients with hepatitis C virus (HCV) infection. To clarify the role of HCV in OLP pathogenesis, we investigated the occurrence and progression of oral lesions in chronic hepatitis C patients treated with interferon. Oral surgeons examined 24 hepatitis C patients (15 men, nine women; mean age 48.1 years) for oral lesions before, during and after interferon (IFN) treatment. OLP was observed in 16.7% (4/24). Two patients had OLP before treatment, one during and one after treatment. Those who developed OLP during or after treatment had neither improvement nor disappearance of OLP even when serum HCV RNA became negative. Leucoplakia was seen in four patients before treatment and oral cancer in one patient 6 months after completing treatment. OLP can occur, exacerbate and persist during IFN treatment for hepatitis C, even when serum HCV RNA becomes negative. The present study suggested that OLP pathogenesis in hepatitis C is due to host factors induced by HCV infection rather than direct HCV participation. Treating physicians should be aware of OLP occurrence or exacerbation by IFN treatment with hepatitis C patients, but IFN therapy is not necessarily contraindicated in these patients.
Decreased release of glutathione into the systemic circulation of patients with HIV infection
Authors: HELBLING B. , VON OVERBECK J. , LAUTERBURG B. H.
Published: November 2003

Low glutathione (GSH) in patients with HIV infection could contribute to their immune deficiency since GSH plays an important role in the function of lymphocytes and sulphydryls decrease the expression of HIV in vitro. In order to gain more insight into the mechanisms responsible for the deranged sulphydryl homeostasis in HIV infection, the release of GSH into the circulation, an estimate of the systemic production of GSH, was determined using a pharmacokinetic approach. The basal plasma concentrations of free GSH (3.3±1.3 vs. 5.3±1.9 μmol L‐1) and cysteine (7.7±2.6 vs. 13.4±4.9 μmol L‐1) were significantly lower in eight HIV‐infected patients than in eight controls. Upon infusion of GSH at a constant rate of 1 μmol min‐1 kg‐1, GSH in plasma reached a new plateau. The increment in plasma GSH was significantly larger in the HIV‐infected patients than in the controls. The input of GSH into the circulation (12.9±5.7 vs. 30.1±11.7 μmol min‐1P<0.01) and the clearance of GSH (25±7 vs. 35±7 mL min‐1 kg‐1) were significantly lower in patients with HIV‐infection. During infusion of GSH the concentration of cysteine in peripheral blood mononuclear cells of the HIV‐infected patients increased significantly. Nevertheless, intracellular GSH did not increase. Thus, the consumption of GSH is not increased in HIV infection. Rather, the present data suggest that GSH in patients with HIV infection is low because of a decreased systemic synthesis of GSH.
Profound decrease of in vivo formation of thromboxane during oestrogen therapy
Authors: HENRIKSSON P. , STEGE R. , GRÉEN K.
Published: November 2003

Oestrogen has been proposed to influence platelet activity and formation of the vasoactive eicosanoids thromboxane and prostacyclin. Previous studies have been based on ex vivo techniques with well‐known artifacts during blood sampling and ex vivo conditions. The present study is the first to assess in vivo formation through gas chromatographic/mass spectrometric analysis of the major urinary metabolites 2,3‐dinor‐thromboxane B2 and 2,3‐dinor‐6‐keto‐PGF1α. Ten consecutive male patients with prostatic carcinoma participating in a randomized study comparing the effects of parenteral oestrogen therapy (n=5) with orchidectomy (n=5) were included. Oestrogen was given as polyestradiol phosphate 240 mg i.m. every month. 2,3‐dinor thromboxane B2 and 2,3‐dinor‐6‐keto‐PGF1α were analysed with the help of tetradeuterated internal carriers/standards. We found a consistent decrease of in vivo formation of thromboxane by ≈40% during parenteral oestrogen therapy (P=0.008) and a doubling after surgical castration. The ratio of prostacyclin to thromboxane increased by ≈50% (P=0.023) during oestrogen therapy. In conclusion, oestrogen induced a marked decrease of in vivo formation of thromboxane and a marked increase in the ratio of prostacyclin to thromboxane formation in all patients. According to current knowledge this should be beneficial for the cardiovascular system. Furthermore, thromboxane formation increased after surgical castration. The latter fact should direct attention to the influence of androgens on thromboxane synthesis. Our findings discloses a marked sex‐hormone sensitivity of the thromboxane‐forming system.
Reduction in thyroid volume after radioiodine therapy of Graves' hyperthyroidism: results of a prospective, randomized, multicentre study
Authors: PETERS H. , FISCHER C. , BOGNER U. , REINERS C. , SCHLEUSENER H.
Published: November 2003

The reduction in thyroid size in 92 patients treated with radioiodine for Graves' thyrotoxicosis was monitored by ultrasound volumetry. The patients were randomly treated with either a standard 131I activity of 555 MBq or an activity calculated to deliver a thyroid dose of 100 Gy. Within 1 year after radioiodine treatment, a remarkable volume reduction of about 71% (median) (quantile 25% (Q 25) = 49%, Q 75 = 82%, n = 67) was observed. The bulk of this reduction (median 57%, Q 25 = 21%, Q 75 = 74%, n = 92) was found within the first 6 months. Statistical analysis reveals that the effect was clearly related to the thyroid dose actually achieved during therapy. The median reduction obtained 6 months after radioiodine application was 45% for <100 Gy, 56% for 100–200 Gy and 67% for >200 Gy (n = 28, 39, 25 respectively). Twelve months after radioiodine application, the effect became less evident: 53%, 68% and 75% respectively (n = 17, 29, 21). The higher median thyroid dose actually achieved by standard than by calculated activity (215 Gy vs. 116 Gy) explains the more pronounced volume reduction in the standard group than in the calculated group: 60% vs. 47% 6 months (n = 47, 45) after radioiodine treatments and 74% vs. 66% 12 months (n = 31, 36) after radioiodine application. The relative reduction in thyroid size was just as marked in patients with large thyroids as in those with small glands. The goitre prevalence (thyroid volume > 20 mL in women and > 25 mL in men) was reduced from 73% to only 16% 1 year after radioiodine treatment. In patients with a thyroid volume of more than 60 mL, the median pretherapeutic thyroid volume of 102 mL was reduced to 29 mL. In conclusion, radioiodine treatment in Graves' hyperthyroidism sufficiently reduces thyroid volume in a dose‐dependent manner. The findings of this study demonstrate that radioiodine is also an attractive mode of therapy for Graves' patients with substantial thyroid enlargement.
Erythrocyte Na+–H+ exchanger kinetics and Na+–Li+ countertransport activity in essential hypertensive patients
Authors: DELVA P. , PASTORI C. , DEGAN M. , MONTESI G. , LECHI C , STEELE A. , LECHI A.
Published: November 2003

The authors measured Na+–H+ exchanger kinetics together with Na+–Li+ countertransport Vmax in the erythrocytes of 21 subjects with essential hypertension and 16 normotensive control subjects. Na+–H+ exchanger Vmax appeared to be increased in patients with essential hypertension, while the Na+–H+ exchanger affinity for intracellular proton sites (K50%) proved to be unchanged and the index of cooperativity among intracellular proton binding sites as measured by Hill's coefficient (Hill's n) decreased as compared with normotensive control subjects. Na+–Li+ countertransport Vmax appeared to be higher in patients with essential hypertension than in control subjects. The authors were unable to find any correlations between Na+–H+ exchanger kinetic parameters and metabolic variables such as parameters of insulin resistance and plasma lipids. On the basis of the data obtained, erythrocyte Na+–H+ exchanger activity was found to be abnormal in two kinetic variables in essential hypertensive patients and showed no simple linear correlations with the main variables of glucose metabolism, plasma lipids, renin or aldosterone.
Daily variation in circulating cytokines and acute‐phase proteins correlates with clinical and laboratory indices in community‐acquired pneumonia
Authors: KOSMAS E. N. , BAXEVANIS C. N. , PAPAMICHAIL M. , KORDOSSIS T.
Published: November 2003

Our objective was to investigate the initial levels of circulating proinflammatory cytokines, such as interleukin 1β (IL‐1β), interleukin 6 (IL‐6), and tumour necrosis factor alpha (TNF‐α), of certain acute‐phase proteins, such as C‐reactive protein (CRP), fibrinogen (FBN) and albumin, and of the glycoprotein fibronectin at presentation and their daily variation during the clinical course of community‐acquired pneumonia (CAP) in relation to clinical and laboratory indices of infection. Thirty otherwise healthy hospitalized patients aged 48 ± 3 years (mean ± SEM) and with bacteriologically confirmed CAP were studied prospectively. IL‐1β and IL‐6 were found to be 15‐fold higher on admission (122 ± 9 pg mL−1 and 60 ± 4 pg mL−1 respectively), whereas TNF‐α was three‐fold higher (102 ± 5 pg mL−1) than those of controls, all of them showing a decline towards normal. Initial CRP levels were increased 90‐fold (416 ± 1 mg L−1), whereas fibronectin levels were reduced (242 ± 9 mg dL−1). The presence of parapneumonic effusion was associated with a higher TNF‐α serum level (127 ± 7 vs. 86 ± 4 pg mL−1, P = 0.0002), a more rapid daily decline in TNF‐α (–7.2 ± 0.7 vs. −3.8 ± 0.5 pg mL−1 day−1, P = 0.0005), a slower rate of decline in CRP (−42.8 ± 3.0 vs. −54.6 ± 3.0 mg L−1 day−1, P = 0.02) and a slower rate of increase in FBN (5.9 ± 1.0 vs. 11.7 ± 1.0 mg dL−1 day−1), P = 0.001]. Furthermore, daily progression of serum levels of cytokines and acute‐phase proteins correlated strongly with pyrexia, erythrocyte sedimentation rate (ESR), neutrophil count, alveolar–arterial oxygen difference and radiographic resolution, clinically manifested by improvement in the patients' condition.
High‐density lipoproteins from probucol‐treated patients have increased capacity to promote cholesterol efflux from mouse peritoneal macrophages loaded with acetylated low‐density lipoproteins
Authors: ISHIGAMI M. , YAMASHITA S. , SAKAI N. , HIRANO K.‐I. , ARAI T. , MARUYAMA T. , TAKAMI S. , KOYAMA M. , KAMEDA‐TAKEMURA K. , MATSUZAWA Y.
Published: November 2003

To elucidate the anti‐atherogenic effect of probucol, high‐density lipoprotein (HDL) was isolated from probucol‐treated patients (n = 14) and compared with that from control subjects (n = 12). The HDL obtained from probucol‐treated patients was low in cholesteryl ester (CE) in comparison with that from control subjects (21.3 ± 3.9 mol per cent vs. 27.6 ± 3.2 mol% of total lipids, P < 0.001), and the peak diameters of patients' HDL were significantly smaller than those of control subjects on 4–30% non‐denaturing polyacrylamide gradient gel electrophoresis (10.6 ± 0.6 nm vs. 12.1 ± 0.4 nm, P < 0.001). These data may be explained by the increased cholesteryl ester transfer protein (CETP) activities of probucol‐treated patients (129 ± 12% of control subjects, P < 0.001). The in vitro ability of HDL to remove CE from lipid‐laden macrophages induced by incubation with acetylated low‐density lipoprotein (Ac‐LDL) was studied. The small and CE‐poor HDL obtained from probucol‐treated patients had a greater capacity to promote CE efflux from macrophages than did control HDL (59.8 ± 6.9% vs. 44.2 ± 5.4%, P < 0.01). Furthermore, the ability of HDL to promote cholesterol efflux correlated negatively with the CE content and particle diameter of HDL (r = −0.561 and r = −0.583 respectively; P < 0.01). When the inhibitory effect of HDL on the incorporation of [14C]‐oleate into cellular cholesteryl ester was compared, the HDL from patients and control subjects inhibited CE formation to a similar extent. The enhanced ability of probucol‐treated patients' HDL may, therefore, be involved in the acceleration of hydrolysis of the CE pool in macrophages. Taken together, we conclude that CETP plays a crucial role in making HDL more active in its anti‐atherogenic function by reducing CE and making HDL smaller, and that probucol may enhance reverse cholesterol transport by activating CE transfer in vivo. The current study demonstrated, for the first time, that HDL modified by enhanced CETP activity in vivo is potentially anti‐atherogenic.
Responses of atrial natriuretic peptide and brain natriuretic peptide to exercise in patients with chronic heart failure and normal control subjects
Authors: STEELE I. C. , McDOWELL G. , MOORE A. , CAMPBELL N. P. S. , SHAW C. , BUCHANAN K. D. , NICHOLLS D. P.
Published: November 2003

Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are known to be elevated in patients with chronic heart failure at rest. While it is known that during exercise the circulating level of ANP increases in patients with heart failure, the response of BNP to exercise in these patients relative to control subjects is unclear. Ten patients with stable chronic heart failure and 10 normal control subjects performed symptom‐limited exercise with respired gas analysis. All patients had depressed left ventricular ejection fractions (LVEF). Patients had lower peak oxygen consumption PV˙O2) than the control group [median (range) 1.18 (0.98–1.76) vs. 1.94 (1.53–2.31) L min−1; P < 0.001]. Circulating plasma levels of ANP and BNP were higher at rest in patients than in control subjects [ANP 335 (140–700) vs. 90 (25–500) pg mL−1; BNP 42 (25–50) vs. 20 (10–20) pg mL−1], and at peak exercise [ANP 400 (200–1000) vs. 130 (10–590); BNP 46 (40–51) vs. 20 (10–30)]. The rise in ANP at peak exercise was significant in patients compared with the resting level, but not in control subjects. For BNP, there was a significant rise in patients but no change in control subjects. The circulating plasma levels of both peptides showed a strong negative correlation with LVEF (ANP, P < 0.005; BNP, P < 0.0001) and, to a less extent, with RVEF. It is possible that BNP may give a better indication of cardiac function.
Systematic use of dystrophin testing in muscle biopsies: results in 201 cases
Authors: DORIGUZZI C. , PALMUCCI L. , MONGINI T. , CHIADÒ‐PIAT L. , MANISCALCO M. , RESTAGNO G.
Published: November 2003

We studied dystrophin with both immunohistochemistry and immunoblotting in 201 muscle biopsies stored in liquid nitrogen during the period 1985–92. The systematic use of dystrophin testing combined with DNA analysis and with 3–10 years' follow‐up of the patients yielded a significant modification of the diagnoses made previously and identified dystrophinopathies with unusual expression and course. Seventeen out of 152 (11.18%) diagnoses in males and 8 out of 49 (16.32%) in females were modified by dystrophin testing. Most diagnostic errors (9 out of 27 diagnoses) were in the group Becker muscular dystrophy–limb girdle muscular dystrophy, confirming the clinical overlap of the two diseases. Unusual expressions of dystrophinopathy included muscular dystrophy with early elbow contractures (two patients), recurrent myoglobinuria (one patient), dilating cardiomyopathy (two patients), myoglobinuria and associated dilating cardiomyopathy (one patient), very late‐onset benign myopathy (two patients and one manifesting carrier) and congenital myopathy (one manifesting carrier). In the group ‘idiopathic hyperCKaemia’, we did not find any dystrophinopathy in 34 males, whereas five out of nine females were found to be carriers. Immunohistochemical analysis of dystrophin using the monoclonal antibody against the C‐terminus detected 99% of protein defects and was found to be the most cost‐effective way of revealing dystrophinopathies. The combined use of immunohistochemical analysis with the antibody against the C‐terminus and immunoblotting with the antibody against the core of the protein appears to be a highly reliable diagnostic approach (100% detection rate).