bluuebunny/crossref_metadata_2025 huggingface dataset:
First‐pass uptake of methotrexate after intra‐arterial bolus injection in human head and neck cancers
Authors: Blöchl‐Daum B. , Mader R. , Millesi W. , Lang S. , Rainer H. , Eglmeier R. , Müller M. , Zanaschka G. , Eichler H. G.
Published: November 2003

The aim of this study was to quantify first‐pass uptake of methotrexate into tumour and healthy tissue after intra‐arterial (i.a.) injection in patients with head and neck cancers. Twenty‐one patients were studied; during surgery, a bolus injection of 10 mg of 3H‐labelled methotrexate was administered into the tumour‐supplying artery. At 15–20 s after injection, and again 2–3 h later, a biopsy of the tumour and of surrounding healthy tissue was taken and radioactivity was measured. In 8 of 17 pretreated patients the biopsy specimens contained no tumour cells. In tumour‐bearing patients, radioactivity in tumour was three times higher than in healthy tissue (P = 0.006). In tumour‐negative patients there was no difference in activity between the two biopsy sites (P = 0.889). However, after 2–3 h the concentration of methotrexate in all surgical specimens returned to near background level and the initial difference between tumour‐positive and tumour‐negative samples was lost. Our results show that i.a. injection of methotrexate does not necessarily lead to high tumour cell exposure.
Complete congenital heart block is associated with increased autoantibody titers against calreticulin
Authors: ORTH T. , DÖRNER T. , MEYER ZUM BÜSCHENFELDE K.‐H. , MAYET W.‐J.
Published: November 2003

Complete congenital heart block (CCHB) is associated with anti‐Ro/SS‐A and anti‐La/SS‐B antibodies. Calreticulin, a calcium‐binding, multifunctional protein of the endoplasmic reticulum with C‐terminal KDEL‐sequence, is not part of the Ro/SS‐A ribonucleoprotein complex. In this study anti‐calreticulin autoantibody responses in serum samples from 18 infants with CCHB, their mothers and in a control group of 11 anti‐Ro/SS‐A or anti‐La/SS‐B positive infants without heart block and their mothers were analysed. Specific enzyme‐linked immunosorbent assays were performed. Nine out of 18 sera with CCHB contained IgG anti‐calreticulin antibodies. Four sera of those with IgG antibodies also had IgM antibodies. One serum contained anti‐calreticulin IgM antibodies only. In the non‐CCHB group two sera were positive for IgG and one serum was positive for IgM anti‐calreticulin antibodies. Sera of healthy infants were negative both for anti‐IgG and anti‐IgM calreticulin antibodies. Calreticulin is involved in calcium storage and therefore anti‐calreticulin antibodies might influence the development of CCHB. The new finding of IgM autoantibodies and the observed differences in antibody response in infants and mothers support the hypothesis of a fetally mediated and passively acquired autoimmune disease.
Erythrocyte membrane fluidity in adult polycystic kidney disease: difference between intact cells and ghost membranes
Authors: VAREESANGTHIP K. , THOMAS T. H. , TONG P. , WILKINSON R.
Published: November 2003

In adult polycystic kidney disease (APCKD) the cytoskeleton of renal tubular cells is abnormal. In erythrocytes the cytoskeleton affects the fluidity of membrane lipids. The authors determined fluorescence anisotropy in intact erythrocytes and erythrocyte ghosts in 12 APCKD patients and 12 normal subjects. In APCKD whole erythrocytes had a much lower core‐region anisotropy, which indicated higher membrane fluidity than normal (mean 0.175 vs. 0.224, P < 0.01). This abnormality was not detected in erythrocyte ghosts, which suggests that preparation of ghosts altered membrane lipid organization. This could be directly due to ghosting or secondary to the loss of cytoskeletal effects, which may be abnormal in APCKD.
In vitro inactivation of mammalian methionine synthase by nitric oxide
Authors: NICOLAOU A. , KENYON S. H. , GIBBONS J. M. , AST T. , Gibbons W. A.
Published: November 2003

The research described here provides one mechanism of uniting current effects of nitric oxide (NO) with the elevated levels of homocysteine detected in patients with cardiovascular and other disease. Time‐ and dose‐dependent studies of the inhibition of purified mammalian methionine synthase by NO were performed. The in vitro study gave an effective IC50 value of 3 μmol L‐1. Methionine synthase converts cellular homocysteine to methionine and is a major enzyme in the biosynthetic pathways for folates, S‐adenosylmethionine and biological methylations, sulphur amino acids and polyamines. Nitric oxide‐induced inactivation of methionine synthase alters the levels of these metabolites and could therefore provide a connection between the cardiovascular effects of NO, the plasma homo‐cysteine levels and cardiovascular diseases that is complementary to the more traditional NO‐induced stimulation of guanylate cyclase and the convertion of homocysteine to oxidized sulphur amino acids.
Elevated cell‐associated levels of interleukin 1β and interleukin 6 in inflamed mucosa of inflammatory bowel disease
Authors: GRÖTTRUP‐WOLFERS E. , MOELLER J. , KARBACH U. , MÜLLER‐LISSNER S. , ENDRES S.
Published: November 2003

The aim of this study was to investigate the involvement of the monocyte‐derived cytokines interleukin 1β (IL‐1β), interleukin 6 (IL‐6) and tumour necrosis factor‐α (TNF‐α) in idiopathic inflammatory bowel disease. Endoscopic biopsies of normal and inflamed intestinal mucosa were obtained from patients with ulcerative colitis (n = 11) and with Crohn’s disease (n = 10). Intestinal mucosal cells were isolated by collagenase digestion. Cell viability, morphology and CD14 expression were determined. To measure cell‐associated cytokine levels, cells were lysed and analysed for IL‐1β and TNF‐α in specific radioimmunoassays and for IL‐6 using a biological assay. Compared with mucosal cells from control patients without inflammatory bowel disease the inflamed intestine in ulcerative colitis and Crohn’s disease displayed markedly enhanced levels of IL‐1β (median 245 pg 10−6 cells, range 30–1275) and IL‐6 (median 22 U 10−6 cells, range 1–298). Non‐inflamed mucosa in patients with ulcerative colitis and Crohn’s disease did not shown elevated levels of IL‐1β (median 50 pg 10−6 cells, range 33–90) or IL‐6 (mean below detection limit of assay, i.e. 1 U 10−6 cells). In contrast, no clear cut difference between inflamed and non‐inflamed mucosa could be detected for TNF‐α. High tissue levels of IL‐6 were associated with a high endoscopic grade of local inflammation. These results suggest that the monocyte‐derived cytokines IL‐1β and IL‐6 are mediators of inflammation in inflammatory bowel disease.
Normalization of peripheral thyroid hormone metabolism induced by successful chronic amiodarone treatment in patients with ventricular arrhythmias
Authors: Iervasi G. , Clerico A. , Berti S. , Pilo A. , Biagini A. , Bianchi R. , Donato L.
Published: November 2003

Amiodarone, an antiarrhythmic agent, is also known to have important effects on the peripheral metabolism of thyroid hormones; the relationship between these two effects of the drug, however, is not well established. We tested the hypothesis that the antiarrhythmic effect of amiodarone might be mediated by its effect on the metabolism of thyroid hormones. Peripheral thyroid hormone metabolism was investigated using a double‐tracer ([125I]‐T4 and [131I]‐T3) procedure in 10 normal volunteers and 10 euthyroid patients with complex ventricular arrhythmias before and during 6 months‘ amiodarone treatment. The underlying cardiac disease was coronary artery disease in four cases, dilated cardiomyopathy in three and idiopathic arrhythmias in three. In all but one patient with complex ventricular arrhythmias amiodarone treatment resulted in a reduction of ≥ 80% of premature ventricular contractions and complete suppression of episodes of ventricular pairs or ventricular tachycardia. In all cases successful treatment with amiodarone was accompanied by normalization of all kinetic parameters: T4 to T3 conversion ratio and T3/T4 molar ratio of production decreased to mean values of 24.7 ± 17.5% and 0.35 ± 0.22% respectively, whereas T4 production rate increased (mean value 75.9 ± 30.0 nmol day−1 m−2). Our kinetic data indicate that long‐term therapy with amiodarone, when effective in suppressing cardiac arrhythmias, also reduces peripheral T4 to T3 conversion, hence restoring the normal peripheral thyroid hormone metabolic pattern. In conclusion, our study confirms that the antiarrhythmic action of amiodarone may be (at least partially) mediated by its action on thyroid hormone metabolism, and may justify the hypothesis that an altered peripheral metabolism of thyroid hormones may play a role in the pathogenesis of complex ventricular arrhythmias.
Echo‐Doppler left ventricular filling abnormalities in patients with rheumatoid arthritis without clinically evident cardiovascular disease
Authors: CORRAO S. , SALLÌ L. , ARNONE S. , SCAGLIONE R. , PINTO A. , LICATA G.
Published: November 2003

Our investigation aimed at verifying diastolic abnormalities in rheumatoid patients, without clinically evident cardiovascular disease and other confounding complaints, by using pulsed Doppler examination of transmitral blood flow. We selected 40 patients fulfilling revised American Rheumatism Association (ARA) criteria for the diagnosis of rheumatoid arthritis having no symptoms of cardiac disease or clinical findings of other extracardiac diseases. We also studied 40 rheumatoid‐matched healthy volunteers as a control group. An echocardiographic examination was carried out on each subject. Left ventricular structural and functional measurements were obtained. Interventricular septal thickness and left ventricular mass index were significantly higher in rheumatoid patients than in the control group. We also found in rheumatoid patients higher mean values of peak A velocity and A/E ratio. When multiple linear regression analysis was performed on the data of rheumatoid patients we found an independent relationship only between A/E ratio and left ventricular mass. In conclusion, our results confirm diastolic abnormalities in rheumatoid patients and point out that these abnormalities also affect echo‐Doppler parameters of left ventricular filling. Moreover, further analysis of our data may suggest the possibility that structural left ventricle changes could be responsible for left ventricular filling impairment.
Increased serum concentrations of the carboxy‐terminal cross‐linked telopeptide of collagen type I in patients with Gram‐negative septicaemia
Authors: WENISCH C. , GRANINGER W. , SCHÖNTHAL E. , RUMPOLD H.
Published: November 2003

The authors determined serum levels of the carboxy‐terminal cross‐linked telopeptide and the carboxy‐terminal propeptide of type 1 collagen (ICTP and PICP) in 18 patients with Gramnegative septicaemia before (day 0) and 28 days after therapy and in 18 age‐ and sex‐matched controls by radioimmunoassay. Elevated levels of ICTP were observed in septicaemic patients [median (range): 15 (7–49) μg L−1 before therapy and 14 (6–45) μg L−1 28 days after therapy vs. 2.1 (1.4–4.3) μg L−1 in normal subjects; P < 0.01 for both], whereas PICP levels were not different between patients and controls [median (range): 119 (52–275) μg L−1 (day 0) and 133 (79–288) μg L−1 (day 28) vs. 91 (54–213) μg L−1 in normal subjects, P > 0.05 for all]. The findings suggest an increased production or release of ICTP in Gram‐negative septicaemia, presumably owing to an alteration of extracellular matrix during septicaemia‐related vascular inflammation.
Differences in phospholipase A2 activity between males and females and Asian Indians and Caucasians
Authors: KUSLYS T. , VISHWANATH B. S. , FREY F. J. , FREY B. M.
Published: November 2003

There is epidemiological evidence that chronic inflammatory diseases occur more frequently in female than in male subjects and prevail differently in various ethnic populations. Phospholipase A2 (PLA2) (group II) plays a key role in many inflammatory reactions by releasing free arachidonic acid, which is a prerequisite for the production of proinflammatory lipid mediators. We therefore, measured PLA2 activity in plasma, serum, leucocytes and lymphocytes in 20 female and 20 male subjects, 10 of each group being of Asian Indian and of Caucasian origin respectively. When PLA2 activity was measured in crude plasma and serum no dependency from gender and ethnicity was observed. Following acid extraction and heating, PLA2 activity in plasma was higher in Caucasians (27.8 ± 2.2 nmol L−1 mg −1 protein 60 min−1) than in Asian Indians (17.9 ± 2.5 nmol L−1 mg−1 protein 60 min−1) (P < 0.005) and higher in females (28.5 ± 2.6 nmol L−1 mg−1 protein 60 min−1) than in males (17.3 ± 2.0 nmol L−1 mg−1 protein 60 min−1) (P < 0.001). Similar differences were observed when only Asian Indian or Caucasian females were compared with their corresponding males. Contrary to plasma, in which the specific activity of PLA2 increased following acid extraction and heating, the activity was completely abrogated in serum after extraction and heating. Lymphocytes exhibited lower activities of PLA2 than neutrophils in all four groups of subjects investigated. Females had a tendency towards higher PLA2 activity in both lymphocytes and neutrophils than males. In conclusion the present investigation revealed an ethnic‐ and sex‐dependent basal activity of PLA2, a key enzyme in the pathogenesis of chronic inflammatory diseases.
Growth hormone potentiates the in vivo biological activities of endotoxin in the rat
Authors: LIAO W. , RUDLING M. , ANGELIN B.
Published: November 2003

To investigate if growth hormone (GH) alters the effects of endotoxin in rats, endotoxin (5 mg kg−1 body weight) was injected into normal rats and into rats primed with GH for 3 days. Endotoxin had injurious effects on renal and liver function and induced hypoglycaemia and hyperlipidaemia as expected. GH‐primed rats became extremely sick after endotoxin challenge and had more marked abnormalities of renal and liver function and much more pronounced hypoglycaemia and hyperlipidaemia than non‐primed rats. It is concluded that growth hormone potentiates the in vivo biological activities of endotoxin in the rat. The results may also suggest that caution should be exerted when considering GH treatment in catabolic situations with endotoxaemia and that special attention should be paid to the prevention of infection during GH therapy in such situations.
Plasma factor VII and its relation to adipose tissue fatty acids and other atherogenic risk factors in healthy men
Authors: CIGOLINI M. , TARGHER G. , SEIDELL J. C. , SCHIAVON R. , TONOLI M. , MUGGEO M. , DE SANDRE G.
Published: November 2003

In this study the authors examined the relationships of plasma factor VII (F–VII) to adipose tissue fatty acid composition, as an objective index of the habitual dietary fat intake, as well as to a number of other atherogenic risk factors in 60 healthy male volunteers (aged 38 years). Significant positive correlations were found between plasma F‐VII [measured as antigen (F‐VIIAg) and coagulant activity, using bovine thromboplastin (F‐VIIbt)] and body mass index (BMI), waist–thigh girth ratio (WTR), cigarette smoking and plasma triglyceride concentration. After adjustment for BMI, only plasma triglycerides remained positively correlated with F‐VII (r = 0.27, P = 0.03, and r = 0.29, P < 0.01, for F‐VIIbt and F‐VIIAg respectively). A significant positive relation was found between F‐VII and the total proportion of fatty acid as monounsaturated fatty acid (r = 0.26, P < 0.05, for F‐VIIAg), whereas inverse relations were found between F‐VII, the total proportion of fatty acid as polyunsaturated fatty acid (r = − 0.26 and r = − 0.25, P < 0.05, for F‐VIIbt and F‐VIIAg respectively), polyunsaturated–saturated fat ratio (r = − 0.25, P < 0.05, for F‐VIIbt) and, more significantly, between F‐VII and adipose‐tissue α‐linolenic acid (r = − 0.29, P < 0.01, for F‐VIIbt and r = − 0.49, P < 0.001, for F‐VIIAg). All these correlations remained significant after matching for BMI. In a multiple linear regression analysis, only adipose tissue α‐linolenic acid was a negative and independent predictor of F‐VIIAg (P = 0.004) and, at borderline significance, of F‐VIIbt (P = 0.061) when allowance was made for BMI, WTR, smoking and plasma triglycerides. In conclusion, this study shows significant relations between F‐VII and adipose tissue fatty acid composition in healthy male individuals; it supports the possibility that adipose tissue poly‐ unsaturated fatty acids, derived from dietary intake, play a role in the relation between F‐VII and coronary heart disease (CHD), thus suggesting that high dietary polyunsaturated fatty acid intake (especially α‐linolenic acid) may reduce the risk for CHD by an improvement of a number of risk factors, including a lowering of plasma F‐VII (both activity and antigen).
Kinetics of soluble TNF‐receptors and soluble adhesion molecules ICAM‐1, E‐selectin and VCAM‐1 under systemic rhTNFα therapy
Authors: Boehme M. W. J. , Waldherr R. , Kist A. , Riedl S. , Walter‐Kirst R. , Kempeni J. , Raeth U.
Published: November 2003

Cytostatic as well as cytotoxic effects of tumour necrosis factor alpha (TNF‐α) therapy have been shown in vitro and in experimental in vivo models. Nevertheless, the mechanism of anti‐tumour activity in humans in vivo remains unclear. To determine the role of the vascular lining endothelial cells as important mediators of several immunological interactions, we investigated changes in the levels of the soluble endothelial cell adhesion molecules intercellular adhesion molecule 1, E‐selectin and vascular cell adhesion molecule 1 as well as of soluble TNF receptors I and II during systemic therapy with recombinant human rhTNF‐α (rhTNF‐α). All tests were performed by enzyme‐linked immunosorbent assays (ELISAs). The clinical efficacy of the intravenous rhTNF‐α therapy was poor. Only one patient with isolated intra‐arterial limb perfusion had a delayed, marked, but only temporary necrosis of tumour cells. In contrast, we found a marked, significant and (during therapy) undulating augmented increase in the levels of soluble adhesion molecules as well as of the soluble TNF receptors. Taken together, these data support the hypothesis that a sufficient tumour‐specific cellular immunity is required to achieve a clinically apparent efficacy of systemic rhTNF‐α therapy in addition to cytokine‐dependent inducible activation mechanisms. In this context, the vascular lining endothelial cells might play an important role as mediators of the complex immunological antitumoral activity.
Computerized evaluation of skin stiffening in scleroderma
Authors: Nikkels‐Tassoudji N. , Henry F. , Piérard‐Franchimont C. , Piérard G. E.
Published: November 2003

Modern non‐invasive biometrological methods have proven to be helpful in monitoring some skin disorders. The present study was designed to evaluate the mechanical properties of skin in systemic scleroderma. The Cutometer SM 474 was used to measure the rheological properties of the skin in 33 patients suffering from scleroderma. The most prominent abnormality consisted in a marked reduction in skin extensibility. Changes occurring in time objectivate the evolution of the disease. Measuring the mechanical properties of skin in patients with scleroderma may be useful in monitoring the disease and its treatment.
The antifibrinolytic effect of lipoprotein(a) in heterozygous subjects is modulated by the relative concentration of each of the apolipoprotein(a) isoforms and their affinity for fibrin
Authors: HERVIO L. , GIRARD‐GLOBA A. , DURLACH V. , ANGLÉS‐CANO E.
Published: November 2003

Individuals heterozygous for the apolipoprotein(a) [apo(a)] trait have phenotypes combining two different lipoprotein(a) [Lp(a)] particle suspecies that are present in plasma at a different concentration. Evaluation of the ability of each of these isoforms to bind to fibrin and affect plasminogen binding is essential to assess the pathogenic role of Lp(a) in these subjects; therefore, fractions containing different ratios of Lp(a) with distinct apo(a) isoforms (e.g. B/S3, S1/S4) were prepared by density gradient ultracentrifugation of plasma, and tested. Lp(a) fractions containing mainly small apo(a) isoforms (either B or S1) showed the highest affinity for fibrin (Kd ∼ 150 nmol L−1) and the best competitor activity for plasminogen, whereas fractions containing mainly the high molecular mass isoforms (either S3 or S4) showed the lowest affinities (Kd ≥ 500 nmol L−1). An increase in Kd was observed as a function of the relative content in isoforms of high molecular mass in these fractions. This inverse relationship between affinity for fibrin and apo(a) size indicates that Lp(a) subspecies in heterozygotes may have different pathogenic potential. Thus, the antifibrinolytic effect of Lp(a) in heterozygous subjects would depend on the relative concentration of the isoform with the highest affinity for fibrin.
Human serum amyloid A (SAA) protein: a prominent acute‐phase reactant for clinical practice
Authors: MALLE E. , DE BEER F. C.
Published: November 2003

Serum amyloid A (SAA) proteins comprise a family of apolipoproteins synthesized in response to cytokines released by activated monocytes/macrophages. Acute‐phase protein concentrations have been advocated as objective biochemical indices of disease activity in a number of different inflammatory processes. Clinical studies in large groups of patients with a variety of disorders confirmed the rapid production and exceptionally wide dynamic range of the SAA response. It is as sensitive a marker for the acute‐phase as C‐reactive protein (CRP). Recent studies indicate that SAA is the most sensitive non‐invasive biochemical marker for allograft rejection. Further studies comparing the measurement of SAA to CRP could reveal other indications for its specific use. These studies are now more feasible given newer assays to measure this acute‐phase reactant. Observations that the acute‐phase response is tightly coupled to lipoprotein abnormalities and the fact that acute‐SAA proteins are mainly associated with plasma lipoproteins of the high density range suggested a possible role of this apolipoprotein (apo SAA) in the development of atherosclerosis. The expression of SAA mRNA in human atherosclerotic lesions and the induction of acute‐phase SAA by oxidized low‐density lipoproteins strengthen the hypothesis that SAA might play a role in vascular injury and atherogenesis.
The isoform‐specific expression of the tri‐iodothyronine receptor in osteoblasts and osteoclasts
Authors: ALLAIN T. J. , YEN P. M. , FLANAGAN A. M. , MCGREGOR A. M.
Published: November 2003

Hyperthyroidism is associated with an increase in both osteoblast and osteoclast activity. We have previously shown that, in vitro, osteoclasts do not respond directly to tri‐iodothyronine to increase bone resorption but that the effect is mediated by another bone cell, probably the osteoblast. To investigate this issue further we have studied the isoform‐specific expression of thyroid receptor (TR) protein in human osteoclasts derived from an osteoclastoma (giant cell tumour of bone) and the expression of TR mRNA and protein in the osteoblastic cell lines MG 63 and UMR 106. Three major TR receptor variants have been described; TRα1 and TRβ are functional receptors whereas c‐erbAα2 is a non‐functional variant. Northern blot analysis using [32P]‐cDNA probes against human TRα1, c‐erbAα2 and TRβ demonstrated specific binding of these probes to mRNA from MG 63 and UMR 106. mRNA for all three receptor variants was observed in both cell lines, in UMR 106 multiple mRNA transcripts were present for TRα1 and TRβ. Immunohistochemical staining with antibodies recognizing a common TRα epitope and specific c‐erbAα2 and TRβ epitopes extended these observations by demonstrating receptor protein in both osteoblasts and osteoclasts. These findings are consistent with previous observations of TR expression in osteoblast‐like cells and are the first direct demonstration of TR in osteoclasts.
Effects of group‐A streptolysin O on neonatal and adult red blood cell deformability and haemolysis
Authors: PÖSCHL J. M. B. , RUEF P. , SCHNAUFFER M. , LINDERKAMP O.
Published: November 2003

Neonates are more susceptible than adults to many Gram‐positive and Gram‐negative bacterial infections. Whereas group B streptococcus causes life‐threatening infections in neonates, group A β‐haemolytic streptococcus infections rarely occur in neonates. To test the hypothesis that group A streptococcus may have different effects on neonatal and adult red blood cells (RBCs), haemolysis and deformability (rheoscope) of RBCs from adults, full‐term and pre‐term neonates were studied during 60 min incubation with 1 haemolytic unit (HU) mL−1 group A streptolysin O (SLO). SLO incubation of adult RBCs resulted in almost linearly increasing time‐dependent haemolysis reaching 82%, whereas haemolysis of neonatal RBCs was below 60% after 1 h. After 60 min SLO incubation, RBC deformation was significantly (P < 0.05) more reduced in adults than in full‐term and preterm neonates. An inverse overall relationship (r = 0.68) between SLO‐induced haemolysis and RBC deformation was found after 60 min of SLO incubation. We conclude that SLO causes less haemolysis and less impairment of RBC deformation in neonates than in adults. The decreased RBC deformation of unhaemolysed RBC indicates that, before lysis, mechanical RBC membrane properties are altered by SLO.
Rate of development of mutation at codon 215 of HIV‐1 reverse transcriptase and its predictive factors at the time of initiation of zidovudine therapy
Authors: LEAL M. , REY C. , TORRES Y. , RELIMPIO F. , PINO R. , LISSEN E. , SÁNCHEZ‐QUIJANO A. , LUQUE F.
Published: November 2003

The objective of the present study was to determine the rate of development of mutation at codon 215 of HIV‐1 reverse transcriptase and to identify baseline characteristics associated with this mutation following initiation of zidovudine therapy. To achieve such a purpose, 80 HIV‐1‐infected patients starting zidovudine therapy have been submitted to clinical, immunological and virological monitoring at entry and every 12 weeks. The critical end point of the study was time to development of mutation at codon 215. The association of key baseline characteristics (CD4+ counts, clinical stage, HIV‐1 p24 antigen, CD8+ counts, serum β‐microglobulin and virus phenotype) with the mutation at codon 215 was also investigated. A total of 38 subjects (48%) developed mutation at codon 215 during follow‐up. The estimated Kaplan–Meier probability of remaining with wild genotype at 24, 48 and 96 weeks (96% CI) was 0.82 (0.73–0.90), 0.70 (0.60–0.80) and 0.53 (0.41–0.66) respectively. Univariate analysis showed that time to the development of mutation at codon 215 was positively associated with baseline p24 positivity, C clinical stage, low CD4+ count and high β‐microglobulin level. Only p24 antigenaemia and CD4+ count remained significantly independent predictive factors for the development of mutation at codon 215 in the Cox proportional hazard stepwise regression analysis [risk ratio (95%CI): 3.67 (1.75–7.70), P=0.0007; 2.89 (1.17–6.72), P=0.0073 respectively]. Thus, a continuous emergence of mutation at codon 215 was observed and HIV‐1 p24 antigenaemia should be considered an independent predictor for faster development of zidovudine resistance.
Prostacyclin (PGI2): a potential mediator of c‐fos expression induced by hydrostatic pressure in osteoblastic cells
Authors: GLANTSCHNIG H. , VARGA F. , RUMPLER M. , KLAUSHOFER K.
Published: November 2003

Application of compressive forces to osteoblastic cells is known to cause specific cellular responses. We report that hydrostatic pressure increased c‐fos mRNA expression in MC3T3‐E1 cells after 15, 30 and 60min. This effect was absent when 5×10−7molL−1 indomethacin, an inhibitor of prostaglandin synthesis, was present in the culture medium during pressurization. Using radioimmunoassays, a significant increase in the concentrations of 6‐keto‐PGF1α, the stable conversion product of prostacyclin (PGI2), in the conditioned medium of pressurized cells, was measured after 60min. In contrast, PGE2 levels were not significantly changed and we therefore assume that under these experimental conditions PGE2 is not responsible for the transduction of the hydrostatic force. However, we also found that PGE2 has the capacity to induce c‐fos mRNA in MC3T3‐E1 cells. Furthermore, we show for the first time that the stable prostacyclin analogue, Iloprost‐Trometamol (Ilomedin), is a potent activator of c‐fos gene transcription. Our data suggest that prostacyclin is a likely candidate in mediating the effect of hydrostatic compressive stress on bone cells by regulating the level of c‐fos mRNA, a member of the activator protein (AP)‐1 complex and potent regulator of osteoblastic proliferation and differentiation.
Induction of heat shock protein 70 genes in human lymphocytes during fever therapy
Authors: Dressel R. , Heine L. , Elsner L. , Geginat G. , Gefeller O. , Kölmel K. F. , Günther E.
Published: November 2003

The induction of heat shock protein 70 (HSP70) genes has been studied in peripheral blood mononuclear cells of individuals undergoing fever therapy because of metastatic malignant melanoma. Induction of HSP70 was assessed at the protein level by metabolic labelling or, for the HLA‐linked HSP70‐1 and HSP70‐2 genes, at the RNA level by in situ hybridization. However, de novo expression of HSP70 could be observed during fever (usually above 39°C) in only about half of the cases. No simple threshold model for inducibility of HSP70 in vivo could be applied. The HSP70‐1 gene was induced more easily than HSP70‐2. Thus, heat‐inducible HSP70 genes, including HLA‐linked HSP70 genes, become expressed in human lymphocytes during fever, but not regularly.
Renovascular hypertension and insulin sensitivity
Authors: NATALI A. , QUIÑONES GALVAN A. , ARZILLI F. , TADDEI S. , PECORI N. , FRASCERRA S. , SALVETTI A. , FERRANNINI E.
Published: November 2003

We tested the hypothesis that the status of the renin–angiotensin–aldosterone system affects insulin sensitivity. Insulin sensitivity (by the euglycaemic insulin clamp technique) was measured in eight patients with angiographically proven renovascular hypertension and in eight normotensive subjects matched for age, gender, body mass index and glucose tolerance. In the patients, insulin sensitivity was measured both at baseline and following 7 days of ACE inhibition. Following glucose ingestion, patients and controls showed similar insulin and glucose responses. Insulin infusion (7 pmol min−1 kg−1) promoted similar glucose utilization in the hypertensives and normotensives: 24.8±2.3 vs. 26.0±3.0μmol min−1 kg−1 respectively. One week of ACE inhibition caused a 20±4 mmHg decrease in mean blood pressure and a 20±6% decrease in peripheral vascular resistance. Plasma angiotensin II concentrations dropped from 24.6±6.3 to 13.5±5.0 pg mL−1 (P<0.05) and plasma aldosterone from 17<4 to 92 ng dL−1 (P<0.05), and plasma renin activity doubled (from 1.6±0.3 to 3.4±1.7 ng mL−1 h−1P<0.02). Nevertheless, insulin sensitivity was unchanged (before, 24.8±2.3; after, 25.8±2.2μmol min−1 kg−1P=Ns). During insulin infusion, forearm blood flow did not change from baseline in either set of studies. Also, the antinatriuretic (before, −26±18; after, −22±14%) and antikaliuretic (before: −36±13%, after: −39±11%) action of the hormone was unaffected by the therapy. In conclusion, human renovascular hypertension is not associated with insulin resistance. Furthermore, a selective, drastic reduction of the renin–angiotensin‐aldosterone system activity and vascular tone does not alter insulin action on glucose and electrolyte metabolism.
Intestinal phase of human antro‐pyloro‐duodenal motility: cholinergic and CCK‐mediated regulation
Authors: KATSCHINSKI M. , SCHIRRA J. , BEGLINGER C. , LANGBEIN S. , WANK U. , D'AMATO M. , ARNOLD R.
Published: November 2003

In this study the muscarinic receptor antagonist atropine and the cholecystokinin (CCK)‐A receptor antagonist loxiglumide were used to investigate the relative importance of cholinergic and CCK‐mediated regulation of intestinal phase antro‐pyloro‐duodenal motility. Plasma levels of gastrointestinal hormones [pancreatic polypeptide (PP), gastrin, CCK] were concomitantly determined to estimate biological potency of the doses of the receptor antagonists. In eight healthy male volunteers, a 30‐min basal interdigestive period was followed by duodenal perfusion of a mixed liquid meal for 150 min at 2.6 kcal min−1 against a background of saline or atropine (5 μg kg−1 h−1) or loxiglumide (10 mg kg−1 h−1). Antro‐pyloro‐duodenal motility was continuously monitored with a sleeve straddling the pylorus. Against a background of saline, duodenal nutrients persistently stimulated isolated pyloric pressure waves. After 60 min, the initially low antral and duodenal contraction rates increased. In the fed state, atropine reduced total number of antral contractions and integrated motility index by 73% (P<0.01) and 76% (P<0.005), total number of pyloric contractions and integrated motility index by 43% and 50% (P<0.05) with inhibition increasing over time. It did not alter duodenal contraction frequency but diminished duodenal motility index by 39% (P<0.05) owing to a reduction in amplitude and duration of contractions. Loxiglumide decreased total numbers of antral, pyloric and duodenal contractions by 44% (P<0.05), 74% (P<0.005) and 41% (P<0.005) respectively. It reduced cumulative antral, pyloric and duodenal motility indexes by 60% (P<0.01), 80% (P<0.01) and 61% (P<0.05) respectively. Atropine fully abolished PP release to duodenal nutrients whereas loxiglumide reduced it by 60% (P<0.05). Both atropine and loxiglumide enhanced gastrin release whereas only loxiglumide markedly stimulated CCK release. We conclude that both cholinergic input and endogenous CCK are major stimulatory regulators of antro‐pyloroduodenal motility in the intestinal phase. There appears to be a regional heterogeneity of cholinergic and CCK control. Cholinergic input predominates in the antrum. Both systems are equipotent at the pylorus. CCK predominates in the duodenum. We suggest that CCK primarily interacts with receptors on cholinergic neurons in the antropyloric region and primarily affects smooth muscle receptors in the duodenum.
Ultrasonic parameters of bone in young normals: effect of age and sex
Authors: MINISOLA S. , TIRAFILI C. , ROSSO R. , COSTA G. , MAZZUOLI G.
Published: November 2003

This study was carried out in order to investigate the early effects of ageing on both broadband ultrasound attenuation and speed of sound through the os calcis. A total of 217 normal subjects, subdivided into 113 fertile women (age range 18–51 years, mean±1 SD=29.4±8.4 years) and 104 age‐matched men (age range 20–49 years, mean29.3±7.1 years), were investigated. Mean broadband ultrasound attenuation values in men (127.3±12.8dBMHz−1) were significantly higher than those found in women (118.3±17.2, P<0.001), whereas no significant differences were found as far as mean speed of sound values was concerned. Both broadband ultrasound attenuation (r=−0.196, P<0.046) and speed of sound (r=−0.226, P<0.02) values were inversely related to age in men; only a decrease of speed of sound values with age was noted in women (r=−0.400, P<0.001). Finally, there was a very high significant correlation between broadband ultrasound attenuation and speed of sound values in men (r=0.458, P<0.001), but this was lacking in women. Admitting that the measurement of broadband ultrasound attenuation is influenced not only by bone density but also by trabecular quantity, spacing and orientation, our results seem to indicate that, even during adulthood, and well before the deleterious effects of oestrogen lack become apparent, structural properties of skeletal tissue in female subjects are disadvantageous with respect to those found in male subjects. Furthermore, while there is a progressive and balanced involvement of both the elastic (as reflected by speed of sound) and the structural properties of skeletal tissue in men, an uncoupling between the two is typical of women.
Dexamethasone and cyclosporin A modulation of cytokine expression and specific antibody synthesis in an allergic bronchopulmonary aspergillosis murine model
Authors: WANG J. M. , CHU H. W. , BOSSÉ M. , ST‐PIERRE J. , BOUTET M. , LAVIOLETTE M.
Published: November 2003

We previously demonstrated that, in C57B1/6 mice, cyclosporin A enhanced and dexamethasone inhibited the Aspergillus fumigatus‐induced pulmonary eosinophilia and total IgE levels. To evaluate whether these effects were related to the modulation of T‐lymphocyte recruitment and activation and cytokine expression, we performed immunohistochemical staining for T‐cell surface marker CD3 and CD4, cell activation marker CD25, and cytokines granulocyte–macrophage colony‐stimulating factor (GM‐CSF), interleukin‐4 (IL‐4) and interleukin‐5 (IL‐5) on lung tissue sections from mice exposed to Aspergillus fumigatus and treated or not with dexamethasone or cyclosporin A. Dexamethasone significantly inhibited Aspergillus fumigatus‐induced increased number of activated T cells and cytokine‐expressing cells in parallel with a decrease in pulmonary eosinophils. In contrast, cyclosporin A did not decrease these immunological events but enhanced the lung eosinophil recruitment. Moreover, dexamethasone prevented the production of immunoglobulins against 76 and 36 kD antigen proteins and cyclosporin A against 76 and 18 kD antigen proteins. These results indicate that dexamethasone down‐regulates and cyclosporin A up‐regulates lung eosinophil recruitment and total IgE production, probably via the modulation of T‐lymphocyte activation and GM‐CSF, IL‐4 and IL‐5 expression. Both drugs inhibit Aspergillus fumigatus‐specific antibody synthesis, but their suppressive actions are selective to different antigenic components.
Epitope mapping of the Ro/SSA60KD autoantigen reveals disease‐specific antibody‐binding profiles
Authors: ROUTSIAS J. G. , TZIOUFAS A. G. , SAKARELLOS‐DAITSIOTIS M. , SAKARELLOS C. , MOUTSOPOULOS H. M.
Published: November 2003

Anti‐Ro60KD autoantibodies are commonly found in sera from patients with primary Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE). In order to identify the epitopes of this autoantigen, 22 ‐mer, synthetic peptides overlapping by eight residues, and covering the entire sequence of the Ro60KD autoantigen were prepared. Three groups of sera were evaluated according to their autoantibody specificities. The first group consisted of monospecific anti Ro60KD sera from four patients with SLE and one with SS, the second one was composed of anti‐Ro60KD + anti‐La(SSB)‐positive sera from four patients with SS and the third group included three normal sera and one anti Ro52KD serum. It was found that sera from SLE patients interact with a common antigenic site spanning the sequence TKYKQRNGWSHKDLLRSHLKP (169–190) of the Ro60KD protein. On the other hand, sera from SS patients recognise the ELYKEKALSVETEKLLKYLEAV (211–232) region of this autoantigen. Determination of the minimal required peptide length for optimal antibody recognition showed that the defined epitopes can be shortened to the NGWSHKDLLR (175–184) and KALSVETEKLLKYLEAV (216–232) sequences respectively. Inhibition experiments using the Ro60KD antigen and soluble peptides corresponding to the 175–184 and 216–232 segments further confirmed the specific antibody binding. These results, although only a small number of sera were used, indicate that the Ro60KD autoantigen, which is not charac‐ terized by disease specificity, contains two discrete epitopes specifically recognized from SLE and SS patient sera. Finally, the sequence similarity of the NGWSHKDLLR (175–184) epitope with some of the HLA haplotypes, associated with anti‐Ro response, deserves to be noted.
Endothelium activation related increase of soluble intercellular adhesion molecule‐1 in human schistosomiasis. Lack of correlation with serology
Authors: LEJOLY‐BOISSEAU H. , BLANN A. D. , SEIGNEUR M. , TRIBOULEY‐DURET J. , TRIBOULEY J. , BOISSEAU M. R.
Published: November 2003

Soluble intercellular adhesion molecule‐1 (sICAM‐1) level was measured in sera from 41 patients with Schistosoma mansoni schistosomiasis and compared with the sICAM‐1 level in 41 healthy subjects. A significant increase in serum sICAM‐1 was observed in patients with schistosomiasis compared with control subjects. As they were inhabitants of the French Antilles, the patients were, however, not settled in a malaria endemic zone, allowing this cause of sICAM‐1 enhancement to be eliminated. No correlation was found between the level of sICAM‐1 and the schistosomiasis serological titre. Such results favour the hypothesis of an activation of vascular endothelial cells due to egg deposition.
Effects of low‐ and conventional‐dose transcutaneous HRT over 2 years on bone metabolism in younger and older postmenopausal women
Authors: Sharp C. A. , Evans S. F. , Risteli L. , Risteli J. , WORSFOLD M. , Davies M. W. J.
Published: November 2003

The minimum dosage of transcutaneous hormone replacement therapy (HRT) able to exert protective effects on postmenopausal bone mass, especially in older women, is uncertain. This study investigates the effects of transcutaneous HRT at two different doses of oestradiol [Estraderm 25 and 50 (E25, E50)] over 2 years in 44 postmenopausal women younger than 67 years and 27 of 67 years and older. Circulating biochemical markers of bone and connective tissue turnover, collagen type I (intact PINP, PICP) and type III (PIIINP) propeptides and type I telopeptide (ICTP), osteocalcin (OC) and alkaline phosphatase (AP) were measured. The responses of the biochemical markers in all the groups were very similar, and most of the observed changes occurred within the first year of treatment. E25 had an effect on the bone markers similar to that of E50, and there was little difference in response according to the patient's age. PINP fell markedly after 1 year in all groups to about half the pretreatment level, with a smaller drop in the second year. PICP responded more variably, and mean values were little changed. There was a slight fall at the higher dose in the younger women, and also in the older women (whose baseline level was higher) on the lower dose. The correlation between PINP and PICP was 0.52 at pretreatment and 0.84 after 2 years of treatment. PIIINP showed no changes. OC and AP both fell in all groups by the first year, but less markedly than PINP. Their response was slightly less pronounced in the older women. ICTP fell marginally in the younger women, and only after 2 years, regardless of dose. Postmenopausal serum oestradiol levels increased after HRT and were associated with decreased binding globulin (SHBG) levels in all groups. After E25 patch application individual serum oestradiol levels were variable and peaked between 13 and 36 h with a median value of 83.8 pmol L–1. Our data suggest that low‐dose transcutaneous HRT restores circulating oestradiol levels in postmenopausal osteopenic women of all ages as effectively as conventional‐dose HRT and is associated with decreased circulating markers of bone and connective tissue turnover.
Direct vasodilator effects of physiological hyperinsulin‐aemia in human skeletal muscle
Authors: Tack C. J. J. , Schefman A. E. P. , Willems J. L. , Thien T. , Lutterman J. A. , Smits P.
Published: November 2003

Systemic hyperinsulinaemia induces vasodilatation in human skeletal muscle. This effect is gradual in onset, and at low insulin levels not maximal until at least 3 h. To investigate whether the vasodilator response to insulin results from a direct vascular effect, we infused insulin directly into the cannulated brachial artery (perfused forearm technique) in a total of 30 experiments in 20 healthy, lean, normotensive volunteers. Local, intra‐arterial, infusion of insulin (180 min, 0.3 mU dL−1 forearm volume min−1, n = 15, forearm venous insulin concentration approximately 540 pmol L−1) induced a gradual increase in forearm blood flow (FBF; venous occlusion plethysmography) from 1.86  ±  0.17 to 3.64  ±  0.64 mL dL−1 min−1 after 180 min (anovaP < 0.001). Percentage increases in FBF after 60, 120 and 180 min averaged 14.4  ±  5.9, 59.4  ±  25.5 and 124.6  ±  51.2% respectively. Forearm glucose uptake increased from 0.24  ±  0.05 to a maximum of 1.98  ±  0.28 μmol dL−1 min  (P < 0.001). Furthermore, insulin infusion increased forearm lactate release and potassium uptake. In 10 out of these 15 individuals, the forearm glucose uptake was further increased in a second, separate, repeat experiment with concomitant intra‐arterial infusion of glucose 5% (0.2 mL dL−1 min−1), resulting in forearm venous glucose concentrations of approximately 15 mmol L−1. This combined infusion achieved a similar vasodilator response to the infusion of insulin alone. The individual vascular responses of the two paired experiments showed a strong correlation (r = 0.87, P < 0.01). In five subjects time and vehicle control experiments were performed, showing no changes in FBF or metabolism during the 180 min. We conclude that the slow vasodilator response to insulin (as observed during systemic infusion) can, at least partly, be explained by a direct vascular effect of insulin. Insulin‐mediated skeletal muscle glucose uptake precedes this effect, but seems not to be an important determinant of the vasodilator response to insulin.
Multifactorial treatment of hypertensive men at high cardiovascular risk and low‐density lipoprotein cholesterol affinity to human arterial proteoglycans
Authors: FAGERBERG B. , WIKLUND O. , AGEWALL S. , CAMEJO G. , WIKSTRAND R. J.
Published: November 2003

The purpose of this work was to examine in an open, randomized parallel‐group study whether an intervention programme directed towards hypercholesterolaemia, smoking and diabetes mellitus in treated hypertensive men was associated with less complex formation between low‐density lipoprotein (LDL) and human arterial proteoglycans than was the case with usual care. The intervention consisted mainly of non‐pharmacological treatment, but drug therapy could be instituted to achieve the treatment goals in the intervention group. The intervention programme was associated with a significant reduction in body mass index, and 46% of the patients were on lipid‐lowering medication at the follow‐up examination. The net differences were (intervention − usual care): change in serum LDL‐cholesterol, −0.48 mmol L−1 (95% confidence interval −0.84 to −0.11 mmol L−1), precipitated LDL‐cholesterol, −5.5 μg (95% CI −9.0 to −1.1 μg). The latter remained after adjustment for the difference in serum LDL‐cholesterol between the groups. Our conclusion is that the multifactorial risk factor treatment programme was associated with a reduced tendency of LDL to form complexes with human arterial proteoglycans.
Tumour necrosis factor alpha stimulates gastrin release from canine and human antral G cells: possible mechanism of the Helicobacter pylori–gastrin link
Authors: Beales I. L. P. , Post L. , Calam J. , Yamada T. , DelValle J.
Published: November 2003

There is evidence that gastric Helicobacter pylori (Hp) infection promotes duodenal ulceration by releasing gastrin. We therefore asked how Hp releases gastrin. Tumour necrosis factor alpha (TNF‐α) is up‐regulated in Hp gastritis and stimulates hormone release from pituitary cells, so we tested its effect on primary cultures of canine antral G cells and human antral fragments. TNF‐α pretreatment (100ngmL–1) of canine G cells significantly increased both basal (by 89%: P<0.01) and bombesin‐stimulated (by 39% P<0.05) gastrin release. A similar pattern of increase was seen following TNF‐α (20ngmL−1) pretreatment of human antral fragments: basal gastrin release was increased by 38% (P < 0.05) and bombesin‐stimulated by 26% (P < 0.05). This effect persisted during immunoblockade with anti‐somatostatin antibody S6. We propose that TNF‐α provides the link between Hp infection and gastrin release and thus contributes to duodenal ulceration.