bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of structurally different lipid emulsions on human neutrophil oxygen radical production
Authors: Wanten  , Naber  , Kruimel  , Tool  , Roos  , Jansen
Published: March 2003

Background

The aim of this study was to evaluate immunomodulatory properties of lipid emulsions applied in parenteral nutrition by measuring neutrophil oxygen radical production (the ‘respiratory burst’) after lipid incubation.

Materials and methods

Neutrophils, isolated from the blood of 10 healthy individuals, were incubated in medium or in lipid emulsions in a physiological concentration (2.5 mmol L−1) containing long‐chain [Intralipid (LCT)], mixed medium and long‐chain [Lipofundin (LCT/MCT)] or structured triglycerides (SL). After washing and stimulation with phorbol 12‐myristate 13‐acetate (PMA) or serum‐treated zymosan (STZ) particles, the respiratory burst was evaluated by measuring maximum oxygen uptake, superoxide and hydrogen peroxide production rates and chemiluminescence.

Results

Unlike LCT and SL, LCT/MCT increased PMA‐ and STZ‐induced oxygen uptake rate by 45% and 31% respectively (both P = 0.006 compared with medium) as well as superoxide (+56%, P = 0.006) and hydrogen peroxide (+14%, P = 0.04) production, within 5 min after stimulation. Increased LCT/MCT‐mediated early respiratory burst was confirmed by decreased PMA‐ (−65%) and STZ‐stimulated (–54%) chemiluminescence peak time (time after stimulation to peak) in combination with unchanged peak height (maximum rate of radical production). Late respiratory burst (within 2 h) of LCT/MCT, indicated by overall luminescence (overall radical production), remained unchanged (PMA) or decreased (STZ, P = 0.02). The addition of 2.5 mmol L−1 LCT/MCT or MCT emulsion to unstimulated neutrophils, in contrast to LCT and SL, resulted in significant luminescence.

Conclusions

Early neutrophil respiratory burst is accelerated by the LCT/MCT emulsion Lipofundin, whereas LCT (Intralipid) and structured lipid emulsions exert no effect. MCT‐containing emulsions, contrary to LCT and structured lipid emulsions, can induce oxygen radical production in unstimulated neutrophils.
Frequency and significance of the A→G (−3826) polymorphism in the promoter of the gene for uncoupling protein‐1 with regard to metabolic parameters and adipocyte transcription factor binding in a large population‐based Caucasian cohort
Authors: Schäffler  , Palitzsch  , Watzlawek  , Drobnik  , Schwer  , Schölmerich  , Schmitz
Published: March 2003

Background

The recently described A→G (−3826) point mutation within the distal region of the UCP‐1 promoter is possibly involved in the development of obesity, diabetes and related metabolic disorders. It was the aim of this study to examine the allelic frequency and the prevalence of the three UCP‐1 genotypes in a broad caucasian cohort and to investigate the significance of this polymorphism for obesity and diabetes.

Methods

1020 subjects were randomly chosen from 6450 participants in the Diabetomobile Study. The UCP‐1 genotype was determined by genomic PCR and Bcl‐I‐RFLP analysis in 1020 subjects and tested for association with a variety of metabolic parameters. In addition, the influence of this mutation on adipocyte nuclear factor binding was investigated by electrophoretic mobility shift assays (EMSA).

Results

The genotype frequencies in 1020 subjects were: AA genotype, 57.0%; AG genotype, 35.4%; GG genotype, 7.6%; with allelic frequencies of 0.75 for allele A and 0.25 for allele G. No significant differences between the genotypes and age, gender, BMI, leptin, glucose, fasting insulin, C‐peptide, HbA1c, diabetes manifestation, total cholesterol, and HDL cholesterol were found. Analysis of the Trp64Arg polymorphism of the β3‐adrenergic receptor in a subgroup of 343 subjects revealed no additive effect to the UCP‐1 polymorphism. An yet unknown adipocyte‐specific factor of nuclear extracts from 3T3‐L1 adipocytes during differentiation is able to bind specifically to the distal UCP‐1 promoter region and this binding ability can not be abolished by the mutation.

Conclusions

We determined the genotype and allelic frequency of the UCP‐1 promoter polymorphism in the largest known population‐based study. The results from genotyping demonstrate clearly that this polymorphism does not play a major role in the pathogenesis obesity and diabetes. A yet unknown adipocyte derived and differentiation‐dependent regulated transcription factor is able to bind to the distal UCP‐1 promoter surrounding −3826 bp. This binding is not affected by presence of the mutation.
Left atrial systolic function is depressed in idiopathic and preserved in ischemic dilated cardiomyopathy
Authors: Triposkiadis  , Moyssakis  , Hadjinikolaou  , Makris  , Zioris  , Hatzizaharias  , Kyriakidis
Published: March 2003

Background

Left atrial systolic dysfunction, unexplained by altered loading conditions, has been reported in idiopathic dilated cardiomyopathy suggesting left atrial involvement in the myopathic process.

Materials and methods

Seventeen patients with idiopathic dilated cardiomyopathy, 16 with ischemic dilated cardiomyopathy and 18 normal controls were studied with transthoracic echocardiography and cardiac catheterization. Transmitral diastolic flow was evaluated with pulsed Doppler. Left atrial volume (cm3/m2) at mitral valve opening (maximal, Vmax.), onset of atrial systole (P wave of the electrocardiogram, Vp), and mitral valve closure (minimal, Vmin.) was determined with two‐dimensional echocardiography using the biplane area‐length method. The left atrial active emptying fraction (ACTEF = [Vp‐Vmin.] × 100/Vp) served as an index of systolic function.

Results

The peak early diastolic transmitral flow velocity (cm/sec) was similar in the three groups (idiopathic: 60 ± 16, ischemic: 58 ± 20, control: 56 ± 22; P = NS), whereas the late diastolic transmitral flow velocity was lower but not significantly different in idiopathic compared to ischemic cardiomyopathy, and in both was lower than control (26 ± 12 vs. 34 ± 13 vs. 44 ± 14, respectively; P < 0.05). Vmax. and Vp were similar in idiopathic and ischemic cardiomyopathy and greater than control (44.6 ± 13.6 vs. 48.2 ± 18.3 vs. 26.9 ± 6.2; P < 0.05, and 34.6 ± 13.4 vs. 30.8 ± 10.9 vs. 16.7 ± 3.7, respectively; P < 0.05). ACTEF was lower in idiopathic than in ischemic cardiomyopathy and in the latter it was similar to control (18 ± 10% vs. 32 ± 10% vs. 36 ± 10%, respectively; P < 0.05). Moreover, ACTEF was inversely related to left atrial tension at end‐of atrial systole both in idiopathic and in ischemic cardiomyopathy (r2 = 0.52, P = 0.001 and r2 = 0.57, P = 0.0007, respectively). However, at any given level of left atrial tension at end of atrial systole, ACTEF was lower in idiopathic than ischemic cardiomyopathy.

Conclusion

Left atrial systolic function is depressed in idiopathic and preserved in ischemic dilated cardiomyopathy despite similar left atrial loading conditions. This finding suggests left atrial myopathy in the former, and may be related to the differences in the response to medical treatment and clinical outcome observed between the two conditions.
Lack of MEN1 gene mutations in 27 sporadic insulinomas
Authors: Cupisti  , Höppner  , Dotzenrath  , Simon  , Berndt  , Röher  , Goretzki
Published: March 2003

Background

Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant familial cancer syndrome characterized by tumours of the parathyroids, anterior pituitary gland and endocrine pancreas. Since the cloning of the MEN1 gene (encoding menin) on chromosome 11q13 by Chandrasekharappa et al. in 1997, it has become possible to identify mutations that are responsible. We examined whether MEN1 gene mutations are present in sporadic insulinomas, a rare sporadic tumour that is seen more frequently in patients with the MEN 1 syndrome.

Patients and methods

We sequenced the coding part of the MEN1 gene (exons 2–10) in tumour tissue of 27 patients suffering from an insulinoma (24 benign, three malignant). To validate our methods we also examined tumour tissue from five patients with primary hyperparathyroidism (HPT) at a younger age and/or multiple gland disease, with increased risk of MEN 1.

Results

We found no mutations in the nine coding exons of the MEN1 gene in the insulinoma tissues. We could confirm three benign polymorphisms (S145S, R171Q, D418D) reported previously. In the control patients we found two new point mutations (one mis‐sense, one non‐sense mutation) and one deletion.

Conclusion

Mutations of the MEN1 gene do not play an important role in the pathogenesis of sporadic insulinomas. Therefore genetic screening is not cost effective in sporadic insulinoma patients without other indicators of MEN 1. Patients with primary HPT at a younger age and/or multiple gland disease should be screened for MEN1 gene mutations.
Criteria for mutation analysis in MEN 1‐suspected patients: MEN 1 case‐finding
Authors: Roijers  , De Wit  , Van Der Luijt  , Ploos van Amstel  , Höppener  , Lips
Published: March 2003

Background

Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal, dominantly inherited cancer syndrome, with tumours in various endocrine glands. In 1997 the responsible tumour suppressor gene was identified. MEN1 gene germ‐line mutations are detected in the vast majority of MEN 1 patients, however, with regard to case‐finding, unfortunately only at a very low frequency in patients with apparently sporadic MEN 1‐related tumours. In order to increase the detection rate of disease gene carriers among patients with apparently sporadic MEN 1‐related tumours, clinical criteria were needed.

Design and Results

In this study MEN1 gene germ‐line mutations were revealed in 16/16 MEN 1 patients/families (100%). Based on our clinical experience with MEN 1 patients/families we formulated clinical criteria to identify disease gene carriers among patients with apparently sporadic MEN 1‐related tumours. The criteria for MEN 1‐suspected patients are: young age at onset (< 35 years) and/or multiple MEN 1‐related lesions in a single organ or two distinct organs affected. Application of these criteria yielded MEN1 gene germ‐line mutations in nine of 15 MEN 1‐suspected patients (60%), thus identifying novel MEN 1 families. Follow up was also guaranteed for patients not fulfilling these criteria.

Conclusions

The clinical criteria for MEN 1‐suspected patients increase the detection rate of germ‐line MEN1 gene mutations among patients with apparently sporadic MEN 1‐related tumours. These criteria may be used for (presymptomatic) identification of MEN 1 disease gene‐carriers, thus enabling early detection of tumour development and timely treatment, as well as genetic counselling.
Angiotensin II type‐I receptor and ACE polymorphisms and risk of myocardial infarction in men and women
Authors: Kee F. , Morrison C. , Poirier O. , McCrum E. , Mallet C. , Nicaud V. , McMaster D. , Dallongeville J. , Fruchart J‐C. , Evans A. E.
Published: March 2003

Findings relating an association between an insertion/deletion polymorphism of the angiotensin converting enzyme (ACE) gene and myocardial infarction (MI) have been mixed. While other loci, such as the angiotensin II type‐I receptor (AT1R), may modulate risk, few studies have adequately documented the risk in women. We aimed to study whether the findings in respect of ACE and AT1R in UK men were borne out in women.

Cases of MI (305 women, 391 men) in Belfast and Glasgow have been compared to controls (291 women, 356 men). These new samples augment the original men (200 cases, 181 controls) included from Belfast in the ECTIM study.

Results Among men, the odds ratio for MI for ACE (DD vs. ID + II) was 1·03 (0·79, 1·34) and among women, 0·69 (0·47, 1·01). This heterogeneity between the risks in men and women was significant in Glasgow (P = 0·02). Among men and women the odds ratio for MI for AT1R (CC vs. AC + AA) was 1·02 (0·71, 1·47). There was a small gradient in risk, such that the odds ratio for DD genotype was 0·86 (0·63, 1·17) among subjects homozygous for the common AT1R alelle (AA): 0·94 (0·67, 1·30) among heterozygotes and 1·21 (0·53, 2·77) among CC subjects; but this interaction was not statistically significant.

Some of the contradictory findings concerning the ACE polymorphism and the risk of MI may be due to heterogeneity in the risk between men and women. The AT1R1196 polymorphism is not an independent risk factor for MI in either sex.
Transcription factors as regulators of steroidogenic P‐450 enzymes
Authors: Peter M. , Dubuis J.‐M.
Published: March 2003

Steroid hormones are essential for normal sexual development, accommodation to stress, and regulation of fluid and electrolyte balance. Biosynthesis of these different classes of steroids and its appropriate regulation requires the precisely controlled expression of six different cytochrome P‐450 enzymes and two hydroxysteroid dehydrogenases in different tissues. The molecular mechanism of the tissue‐specific and pituitary hormone‐regulated expression of the genes encoding P‐450 enzymes in the steroidogenic tissues is the central problem of long‐term regulation of steroidogenesis. Orphan members of the nuclear receptor superfamily play an important role in mediating transcriptional regulation of several steroid hydroxylase genes. Two of these transcription factors, steroidogenic factor‐1 (SF‐1) and DAX‐1, will be reviewed here in detail.
Changes of gallbladder and gastric dynamics in patients with acute hepatitis A
Authors: Portincasa P. , Moschetta A. , Di Ciaula A. , O. Palmieri V. , Milella M. , Pastore G. , Palasciano G.
Published: March 2003

Transient alterations of gallbladder morphology and dynamics have been reported in patients with during acute hepatitis A. The presence of dyspepsia also suggests involvement of gastric motility. During a 60‐day follow‐up, we investigated gallbladder and gastric motility in relation to dyspepsia in acute viral hepatitis A patients.

Twenty patients were assessed at referral (day 0) and at days 7, 21, 42 and 60 and compared with 20 healthy volunteers. Gallbladder morphology and motility and gastric motility were assessed in the fasting and postprandial period by functional ultrasonography using a liquid test meal. Dyspeptic symptoms were scored.

At day 0, fasting gallbladder volume was 5·9 ± 1·3 mL, 32·6 ± 4·6 mL, and 21·5 ± 1·9 mL (mean ± SE) in patients with gallbladder sludge (n = 7), without sludge (n = 13) and controls, respectively (P < 0·05 in sludge vs. no sludge and controls; P < 0·05 in no sludge vs. controls, anova). Small fasting gallbladder volume in patients with sludge increased and sludge disappeared within 7 days. At day 0, patients with sludge also had increased thickness of fasting gallbladder wall and increased serum transaminase levels compared with patients without sludge and controls. Gallbladder contraction was similar in patients and controls. However, patients had delayed gastric emptying, which positively correlated with dyspepsia score.

Gallbladder morphological changes observed in the acute phase of hepatitis A are transient and are associated with hepatocellular damage. Gastric emptying is delayed during the first week of disease and is associated with dyspeptic symptoms.
Left ventricular hypertrophy increases transepicardial dispersion of repolarisation in hypertensive patients: a differential effect on QTpeak and QTend dispersion
Authors: Wolk R. , Mazurek T. , Lusawa T. , Wasek W. , Rezler J.
Published: March 2003

Background Ventricular arrhythmias in left ventricular hypertrophy (LVH) are related to regional electrical heterogeneity. The significance of noninvasive electrocardiographic indices of electrical heterogeneity in LVH has not been established. The aim of the study was to investigate changes in the Tpeak–Tend interval (an index of transmural dispersion of repolarisation) in addition to other traditional electrocardiographic indices of electrical dispersion in patients with hypertensive LVH.

Methods Consecutive patients were screened for the presence of hypertensive echocardiographic LVH and compared with a control group. LVH was identified as left ventricular mass > 134 g m−2 in men and > 110 g m−2 in women. Twelve‐lead ECGs were analysed in respect of various indices of electrical dispersion.

Results Left ventricular mass was greater in the LVH than in the control group (174 ± 39 vs. 101 ± 18 g m−2, P < 0·0001). The Tpeak–Tend interval was not affected by LVH. The main effect of LVH was an increase in QTpeak dispersion (40 ± 13 vs. 53 ± 21 ms, P < 0·05), which resulted from an increase in the maximum QTpeak interval (337 ± 24 vs. 358 ± 30 ms, P < 0·04), without any change in the minimum QTpeak interval. There was a significant correlation between the left ventricular mass index and QTpeak dispersion (r = 0·40; P < 0·01). In contrast, LVH did not exert any effect on QTend dispersion (65 ± 21 vs. 65 ± 16 ms, ns), because LVH increased both the maximum QTend interval (430 ± 30 vs. 449 ± 28 ms, P < 0·05) and the minimum QTend interval (365 ± 29 vs. 384 ± 27 ms, P < 0·04).

Conclusions Hypertensive LVH exerts a differential effect on QTpeak and QTend interval dispersion. The most likely explanation is that these changes reflect a nonuniform prolongation of action potential duration across the epicardium, leading to an increase in transepicardial dispersion of repolarisation.
Damaged myocytes as detected by the colocalization of DNA fragmentation and tissue transglutaminase and their prognostic significance in enterovirus‐associated dilated cardiomyopathy
Authors: Lotze U. , Busch H.‐J. , Aschoff A. , Glück B. , Sigusch H. , Jirikowski G. , Stelzner A. , Figull H. R.
Published: March 2003

Background Apoptotic cardiac myocytes have been described in chronic heart failure, but no data exist on the relationship between these ‘damaged’ myocytes and myocardial detection of enterovirus RNA often associated with dilated cardiomyopathy (DCM).

Design In patients with idiopathic DCM, endomyocardial biopsy samples were studied for enteroviral RNA by one step reverse transcription‐polymerase chain reaction (PCR) and a subsequent hybridization of the PCR product using a Southern blot technique. The endomyocardial biopsies were further investigated for markers of cell damage and apoptosis: DNA fragmentation and expression of tissue‐transglutaminase (TTG) in the myocytes using the in‐situ endlabelling method or an anti‐TTG‐staining, respectively. To assess the prognostic significance of these two markers the correlation between the percentage of myocytes positive both for DNA fragmentation and TTG (the index of damaged myocytes) and the hemodynamic course of the patients during a mean follow‐up period of 15·9 ± 6·2 months was investigated prospectively by echocardiography.

Results In 14 (45%) of the 31 patients with idiopathic DCM, enteroviral RNA was found in the endomyocardial biopsy samples, while 17 patients (55%) were enterovirus‐negative. In enterovirus‐positive patients, the index of ‘damaged’ myocytes was significantly lower (10·7 ± 4·9% vs. 19·2 ± 8·8%, P = 0·002) and the left ventricular ejection fraction (LVEF) improved significantly (P = 0·00017 vs. P = 0·13) during long‐term follow‐up. In addition, a weak negative correlation was seen between the index of damaged myocytes and the changes in LVEF in all patients during long‐term follow‐up (r = − 0·48, P = 0·004).

Conclusion Our results favour the view that enterovirus‐positive patients with DCM have less damaged myocytes and a better haemodynamic course than enterovirus‐negative patients.
Nonsteroidal anti‐inflammatory drugs stimulate spermidine/spermine acetyltransferase and deplete polyamine content in colon cancer cells
Authors: Turchanowa L. , Dauletbaev N. , Milovic V. , Stein J.
Published: March 2003

Background Nonsteroidal anti‐inflammatory drugs (NSAIDs) inhibit colonic tumourigenesis and have an established usefulness in cancer prevention. Because polyamines are essential for neoplastic cell growth, the aim of this study was to evaluate the effect of NSAIDs (indomethacin, a nonselective COX‐1 and COX‐2 inhibitor) on polyamine metabolism in colon cancer cells.

Methods Both cell counting and thymidine incorporation into cellular DNA were used to assess colon cancer cell growth. Activities of polyamine‐metabolising enzymes, polyamine content (HPLC) and ODC and c‐myc protein expression (Western blot) were measured in colon cancer cells treated with indomethacin during logarithmic phase of proliferation.

Results Indomethacin impaired growth of human colon cancer cells (Caco‐2 and HCT‐116). As a result, ornithine decarboxylase activity and c‐myc protein expression were decreased. Treatment with indomethacin induced intracellular oxidant formation in colon cancer cells significantly increased the spermidine/spermine‐acetyltrasferase activity (SSAT) and enhanced polyamine acetylation and efflux from colon cancer cells. Impairment of cell growth by indomethacin could not be reversed by exogenous polyamines.

Conclusion Taken together, our results suggest that NSAIDs affect polyamine metabolism in colon cancer cells by inducing SSAT activity, and that polyamine depletion in NSAID‐treated colon cancer cells is mainly due to enhanced polyamine acetylation and irreversible depletion of intracellular polyamine pools.
Myocardial fibrosis in transforming growth factor‐β1 (TGF‐β1) transgenic mice is associated with inhibition of interstitial collagenase
Authors: Seeland U. , Haeuseler C. , Hinrichs R. , Rosenkranz S. , Pfitzner T. , Scharffetter‐Kochanek K. , Böhm M.
Published: March 2003

Background TGF‐β1 mediates effects on fibroblast proliferation and collagen synthesis in the myocardium. The extracellular matrix remodeling depends on the fibrillar collagen degrading matrix metalloproteinases (MMPs) and their inhibitors (TIMPs). The in vivo effects of TGF‐β1 on the MMP/TIMP system in TGF‐β1 overexpressing transgenic mice were studied.

Methods Male Alb/TGF‐β1(cys223,225ser) transgenic mice (TG) and nontransgenic controls (C; 8 weeks) were examined. Protein expression of collagen type I, ‐III, interstitial collagenase (Int Coll), MMP‐2, ‐9, TIMP‐1, ‐2, ‐4 and TGF‐β1 as well as enzyme activity (MMP‐2, ‐9) were measured (Western blots, zymographic assays). mRNA expression of the interstitial collagenase and MMP‐9 was studied with the Light‐Cycler based real‐time PCR.

Results Overexpression of TGF‐β1 resulted in a 10‐fold increase in plasma and a seven‐fold increase in myocardial TGF‐β1 concentrations. Relative heart weights increased (mg g−1: 7·8 ± 0·4 vs. 4·8 ± 0·6, n= 6; P < 0·01) in TG compared to C. Collagen type I and III increased in TG (1·9‐fold and 1·7‐fold) compared to controls. Interstitial collagenase protein activity (− 91%) and mRNA expression (−75%) in TG were reduced (P < 0·05–P < 0·001). Gelatinase (MMP‐2, MMP‐9) expression and activity were not significantly alterated. MMP‐inhibitors were increased 2·5‐fold (TIMP‐1, ‐4) and 6‐fold (TIMP‐2) in TG.

Conclusions TGF‐β1 produces myocardial fibrosis in vivo. This effect is not only produced by a stimulation of matrix protein formation: a complex regulation of MMP and TIMP interaction, namely decrease of expression and activity of interstitial collagenase and an enhanced inhibition by increased levels of TIMPs, are involved. These mechanisms are optional targets for therapeutic interventions in myocardial diseases.
Relevance of apoptosis and cell proliferation for survival of patients with dilated cardiomyopathy undergoing partial left ventriculectomy
Authors: Metzger M. , Higuchi M. L. , Moreira L. F. , Chaves M. J. F. , Castelli J. B. , Silvestre J. M. L. , Bocchi E. , Stolf N. , Ramires J. A.
Published: March 2003

Background Cardiomyocyte apoptosis as well as proliferation have been described in congestive heart failure, but their clinical relevance remains unclear. In order to clarify whether apoptosis and cell proliferation occur in patients with idiopathic dilated cardiomyopathy and whether their degree in left ventricle fragments resected during partial left ventriculectomy has any influence on the outcome after this surgery, we compared their occurrence in four groups of patients: group A, short‐term survivors (n = 18); group B, deaths within 6 months of the surgery (n = 13); group C, long‐term survivors (n = 12); and Group D, deaths within 60 months (n = 19).

Design Apoptotic cardiomyocytes and interstitial cells were quantified in left ventricle fragments from 31 patients with idiopathic‐dilated cardiomyopathy using the TUNEL assay. Cell proliferation was quantified in parallel sections by KI‐67 immunohistochemistry.

Results Apoptotic cells were present in the majority of cases (n = 24) and proliferative cells in all cases. Whereas there was no significant difference regarding all parameters examined between Groups A and B, there was a highly significant difference between Groups C and D in the number of apoptotic cardiomyocytes (P = 0·012) and apoptotic interstitial cells (P = 0·006). There was no significant relationship between apoptotic cardiomyocytes and KI‐67‐positive cardiomyocytes, but a negative correlation between apoptotic interstitial cells and KI‐67‐positive interstitial cells (r = −0·383; P = 0·028).

Conclusion Cardiomyocyte apoptosis and proliferation occur in the majority of patients with idiopathic‐dilated cardiomyopathy. High numbers of apoptotic cardiomyocytes and apoptotic interstitial cells are significantly related to a bad late outcome after partial left ventriculectomy.
Inhibition of human primary melanoma cell proliferation by histamine is enhanced by interleukin‐6
Authors: Lázár‐Molnár E. , Hegyesi H. , Pállinger É. , Kovács P. , Tóth S. , Fitzsimons C. , Cricco G. , Martin G. , Bergoc R. , Darvas Z. , Rivera E. S. , Falus A.
Published: March 2003

Background Interleukin‐6 (IL‐6) is a bifunctional growth factor in malignant melanoma; its expression increases during the malignant progression of the disease. Histamine, detected in large amounts in normal and pathological proliferating tissues, is an important paracrine and autocrine regulator of normal and tumour cell proliferation as well.

Materials and methods We investigated the presence and function of IL‐6 and histamine in the WM35 primary human melanoma cell line with respect to their direct role in cell proliferation and their regulatory interactions.

Results IL‐6 inhibited the proliferation of WM35 melanoma cells and increased significantly the expression of histidine decarboxylase as well as histamine production. It had dose‐dependent effects on the proliferation: high concentration (10−5 M) was inhibitory through H1 histamine receptors while low histamine concentration acting on H2 receptors, with a simultaneous increase of cAMP, enhanced colony formation in the monolayer. Furthermore, IL‐6 increased the H1‐ but decreased the H2‐histamine receptor expression of the melanoma cells. On the other hand, histamine was locally synthesized by the WM35 melanoma cells.

Conclusion We suggest that the growth arrest induced by IL‐6 is in part mediated by its dual action on histamine: a shift toward H1 receptor predominance and an elevation of locally produced histamine with prevalent action on the inhibitory response triggered through the H1 receptor. These findings suggest a local cross‐talk between histamine and IL‐6 in the regulation of melanoma growth.
Basal TSH levels compared with TRH‐stimulated TSH levels to diagnose different degrees of TSH suppression: diagnostic and therapeutic impact of assay performance
Authors: Christ‐Crain M. , Meier C. , Roth C.‐B. , Huber P. , Staub J.‐J. , Müller B.
Published: March 2003

Background The estimated prevalence of endogenous subclinical hyperthyroidism varies from 4% to 6% and a basal thyroid stimulating hormone (TSH) level < 0·5 mU L−1 may be associated with increased mortality in subjects over 60 years of age who are not on thyroid medication. Exogenous TSH suppression is a mainstay in the treatment of thyroid cancer. Because of recent concerns about potential adverse effects, especially of endogenous TSH suppression on bone, the cardiovascular system and cognitive functions, subclinical hyperthyroidism obtained new clinical importance. We therefore re‐evaluated the diagnostic value of basal and thyrotrop in TRH‐stimulated serum TSH measurements using TSH assays with different sensitivities.

Materials and methods A total of 805 oral and nasal TRH stimulation tests were performed on 409 ambulatory subjects with low basal serum TSH concentrations of less than 0·1 mIU L−1. Basal serum TSH was measured either using a second generation assay (functional sensitivity > 0·03 mIU L−1) or two third generation assays (functional sensitivity 0·01 mIU L−1 and 0·007 mU L−1, respectively). Serum TSH concentration was determined before and 3 h after oral administration of 40 mg of TRH and before and 30 min after nasal administration of 2 mg of TRH.

Results In the oral testing group, the basal TSH levels measured by the different TSH assays were 0·06 ± 0·03, 0·04 ± 0·02 and 0·03 ± 0·02, respectively, whereas the peak TSH levels were 0·4 ± 0·6, 0·4 ± 0·6 and 0·3 ± 0·5 in the patients with subclinical hyperthyroidism. In overt hyperthyroidism, the basal TSH levels were 0·06 ± 0·02, 0·03 ± 0·02 and 0·03 ± 0·02, whereas the peak TSH levels were 0·19 ± 0·3, 0·16 ± 0·3 and 0·15 ± 0·2, respectively. Basal TSH values could discriminate between different degrees of TSH suppression if measured with a third generation assay (P < 0·001), but not with a second generation assay. There was only a weak correlation between basal TSH and peak TSH when measured by a second generation assay (n = 126; r = 0·3; P < 0·001) in contrast to the strong correlation found using the third generation assays (n = 128; r = 0·7; P < 0·001 and n = 69; r = 0·8; P < 0·001, respectively).

Conclusions In view of the recent concerns about potential adverse effects in TSH suppression and based on our data, it is mandatory to select a TSH assay with a functional sensitivity of ≤ 0·01 mIU L−1 for optimal titration of L‐T4 suppressive therapy, especially in patients with thyroid cancer. If, however, only a second generation TSH assay is available, additional TRH testing allows a more careful titration of suppressive thyroxine therapy.
S‐adenosylhomocysteine and the ratio of S‐adenosylmethionine to S‐adenosylhomocysteine are not related to folate, cobalamin and vitamin B6 concentrations
Authors: Becker A. , Smulders Y. M. , Teerlink T. , Struys E. A. , De Meer K. , Kostense P. J. , Jakobs C. , Dekker J. M. , Nijpels G. , Heine R. J. , Bouter L. M. , Stehouwer C. D. A.
Published: March 2003

Background It is unclear whether homocysteine itself is causal in the pathogenesis of cardiovascular disease. Alternatively or additionally, the association between homocysteine and cardiovascular disease may be because of its metabolic precursor, S‐adenosylhomocysteine, or of the ratio of S‐adenosylmethionine to S‐adenosylhomocysteine. Therefore, it is relevant to know how these moieties are interrelated, and whether, as is the case for homocysteine, they are influenced by blood levels of folate, cobalamin or vitamin B6.

Design We cross‐sectionally studied a population‐based cohort of 97 Caucasian subjects aged 60–85 years. Concentrations of homocysteine, S‐adenosylhomocysteine, S‐adenosylmethionine, folate, cobalamin and vitamin B6 were measured in fasting blood samples.

Results In multiple regression analysis, homocysteine was associated with vitamin B12 (per 50 pmol L−1 increase of cobalamin, change in homocysteine, –0·70 mmol L−1; 95% CI, −1·30 to −0·10 mmol L−1) and folate (per 100 nmol L−1 increase in erythrocyte folate, change in homocysteine, –0·68 mmol L−1; 95% CI −1·28 to −0·08 mmol L−1). S‐adenosylhomocysteine, S‐adenosylmethionine and the ratio of S‐adenosylmethionine to S‐adenosylhomocysteine were not associated with serum folate, cobalamin or vitamin B6, nor with erythrocyte folate. Furthermore, plasma homocysteine showed a negative correlation with the ratio of S‐adenosylmethionine to S‐adenosylhomocysteine in plasma (r = −0·27; P < 0·01) but not in erythrocytes.

Conclusions In contrast to homocysteine, the plasma concentrations of S‐adenosylhomocysteine and the ratio of S‐adenosylmethionine to S‐adenosylhomocysteine were not associated with the folate, cobalamin and vitamin B6 concentrations in the present study. If these precursors in part explain why homocysteine is associated with cardiovascular disease, homocysteine‐lowering treatment with B vitamins may be less effective than currently expected, at least in an elderly population.
HLA antigens and haplotypes in IgA‐deficient Brazilian paediatric patients
Authors: Gerbase‐Delima M. , Pinto L. C. , Grumach A. , Carneiro‐Sampaio M. M. S.
Published: March 2003

In the present study we determined the HLA‐A, B and DR antigenic and haplotypic frequencies in unrelated Brazilian Caucasian paediatric patients with IgA deficiency (IgA‐D). Out of 17 IgA‐D subjects typed for HLA A and B specificities, 12 (71%) presented B8 and/or B14; of 15 patients also typed for HLA‐DR specificities, 14 (93%) were positive for at least one of the HLA markers previously reported to be associated with IgA‐D, i.e. B8, B14, DR1, DR3 or DR7. The haplotypes B8, DR3, B14, DR1 and B13, DR7 were present in 43, 21 and 14% of the cases, respectively, while they have a frequency in the general population of 2, 2 and 1%, respectively. The concomitant association with the three IgA‐associated haplotypes found in our study probably reflects the admixture of European genetic influences present in the Brazilian Caucasian population of São Paulo.
The distribution of HLA‐DRB alleles in ulcerative colitis patients in Turkey
Authors: Uyar F. A. , Ìmeryüz N. , Saruhan‐Direskeneli G. , Çeken H. , Özdog˘an Ö. , S,ahin S , Tözün N.
Published: March 2003

Recently described distinct associations of HLA class II genes with ulcerative colitis (UC) suggest a genetic heterogeneity for disease susceptibility. In this study, HLA‐DRB alleles of UC patients (n = 59) from Turkey were investigated and compared with healthy controls (n = 244). Using molecular genotyping by polymerase chain reaction (PCR) and sequence‐specific oligonucleotide hybridization, we have shown a positive association of UC patients with the HLA‐DRB1*1502 allele (10/59 vs. 16/244; P = 0.02; OR: 2.9) and a negative association with the DRB1*13 allele (7/59 vs. 64/244; P = 0.03; OR: 0.38) compared to controls. HLA‐DRB1*0701 was significantly increased in perinuclear antineutrophil cytoplasmic antibody (pANCA)‐positive UC patients compared to pANCA‐negative patients (8/32 vs. 0/27; P = 0.005), whereas DRB1*1502 was observed more frequently in pANCA‐negative patients (8/27 vs. 2/32; P = 0.03). These results extended the reported positive association of DRB1*1502 with UC to another population and supported the genetic susceptibility associated with HLA genes for disease development.
Heterogeneity of HLA‐DR2 haplotypes in Caucasoid Americans, African Americans, Chinese Americans, Native Americans and Xiamen Chinese
Authors: Lee A. , Huang R. , Yan L. , Shaw C. K. , Zeng S. , Lin P. Y. , Lee T. D.
Published: March 2003

HLA‐DR, ‐DQ specificities were determined by PCR amplification with SSOP in 4560 individuals: Caucasoid Americans (CA), African Americans (AA), Chinese Americans (ChA), Native Americans (NA) and Xiamen Chinese (XC). DR2 subtypes were compared amongst the five ethnic populations. The DRB1*1501‐DRB5*0101 haplotype was found to be the most frequent in all populations except African Americans, in which DRB1*1503‐DRB5*0101 was the predominant haplotype, accounting for 65% of DR2 subtypes. In contrast to Caucasoid Americans, the DRB1*1602 is strongly associated with the DRB5*0101 allele in Chinese populations. The presence of DRB5*0203 and DRB1*1602‐DRB5*0101 haplotypes in Chinese populations, especially in Xiamen Chinese, suggests that various DR2 haplotypes may be generated via multiple gene conversion events together with point mutations and reciprocal recombination. The strong DR and DQ associations are found in DRB1*1501/DQB1*0602 (66.22%) for CA, DRB1*1503/DQB1*0602 (56.58%) for AA, DRB1*1501/DQB1*0602 (30.20%) and DRB1*1602/ DQB1*0502 (15.76%) for ChA, DRB1* 1501/ DQB1*0602 (41.55%) and DRB1*1602/ DQB1*0301 (40.25%) for NA, and DRB1*1501/ DQB1*0602 (30.26%) and DRB1*1602/DQB1*0502 (25.81%) for XC.
Antigenic stimulation in T‐cell cultures in cardiomyopathies: differences in cytokine profiles
Authors: Boura P. , Lefkos N. , Boudonas G. , Kountouras J. , Zacharioudaki E. , Efthimiadis AP. , Tsapas G.
Published: March 2003

Immune‐mediated mechanisms are involved in the pathogenesis of cardiomyopathies. In this study, we investigate which pattern of immune response (Th1or Th2) lies behind these diseases by analysing the basic cytokines secreted from PHA‐cultured T lymphocytes and determining what differences, if any, exist between dilated cardiomyopathy (DMC) and hypertrophic cardiomyopathy (HCM). Two groups of patients were studied: 10 patients with DCM and 10 patients with HCM. Age‐ and sex‐matched healthy individuals were used as controls. PHA‐cultured T lymphocytes in the presence or absence of different myocardial antigen (MA) concentrations were measured. Interleukine‐2 (IL‐2), Interleukine‐6 (IL‐6) and Interferon‐γ (IFN‐γ) levels were measured in culture supernatants by an ELISA method. At the same time, delayed‐type hypereactivity (DTH) against the same antigenic preparation was measured by the leukocyte migration inhibitory index technique. Patients were subdivided into DTH‐positive and DTH‐negative and re‐examined for IL‐2 cytokine expression. IL‐6 levels were found to increase both in the presence and in the absence of MA in the patient groups compared to the controls. IL‐2 levels were decreased in both groups, in an antigen dose‐related manner. Anergic patients showed a further reduction in IL‐2 levels for both groups of patients. IFN‐γ remained unaffected in the patient groups. Almost half of the patients exhibited anergy to the DTH reaction against MA. We conclude that, upon antigenic stimulation, the initially mounted immune response (increased IL‐6) is somehow blocked/switched off in patients, resulting in an immunologic tolerance/unresponsiveness to MA (IL‐2 decreased, IFN‐γ unchanged). Finally, increased IL‐6 could lead to a perpetuation of immunologic injury through the release of oxygen‐free radicals with a cytotoxic effect on the myocardium. We hypothesize an antigen‐related, defective macrophage‐Th1cell reaction, which accounts for the differences in the IL‐2 profile between the DCM and HCM groups, that might cause local immune responses to lead to immunosuppression (immune tolerance effect), thus contributing to the pathogenesis of cardiomyopathies.
Nationwide collaborative study of HLA class II associations with distinct types of juvenile chronic arthritis (JCA) in Greece
Authors: Pratsidou‐Gertsi P. , Kanakoudi‐Tsakalidou F. , Spyropoulou M. , Germenis A. , Adam K. , Taparkou A. , Siamopoulou A. , Drakou C. , Konstantinidis T. , Prieur A. M. , Stavropoulos‐Giokas C.
Published: March 2003

The aim of this study was to investigate the association of different groups and subgroups of juvenile chronic arthritis (JCA) with HLA class II (DR, DP, DQ) alleles and/or haplotypes. Groups and subgroups were mainly distinguished on the basis of the type of onset, the course and complications of the disease, and some predefined disease markers according to the criteria proposed by the ILAR Standing Committee (Chile, 1994). On the basis of these criteria the following five JCA groups and their subgroups were included in the study: (1) definite systemic onset (n = 25) and systemic progressing to persistent arthritis (n = 14); (2) JCA of oligoarthritis onset (O‐JCA, n = 124) and of oligoarthritis onset and course (n = 98), O‐JCA of early (< 6 years) or late (> 6 years) onset (EOO‐JCA n = 71 and LOO‐JCA n = 44), O‐JCA with ANA positive (n = 69) or negative (n = 55) and O‐JCA progressing to extended arthritis (n = 22); (3) JCA of polyarthritis onset (P‐JCA) with rheumatic factor (RF) negative (n = 29), and P‐JCA RF negative with antinuclear antibodies (ANA) positive (n = 13) or negative (n = 16); (4) JCA complicated with chronic anterior uveitis (CAU, n = 32); (5) juvenile psoriatic arthritis (n = 20). To assess the HLA allele frequencies in the above 223 Greek children with JCA, these frequencies were compared to those of 98 age‐matched and 250 adult controls. The main findings were the following. A common HLA‐DRB1* allele was not involved in the JCA groups and subgroups studied; on the other hand, the DQA1*0501 allele was found to be associated with different JCA groups/subgroups (O‐JCA, P‐JCA RF‐negative ANA‐positive, JCA with CAU), probably suggesting a closer relationship of this locus with the immunogenetic background of JCA. The DPB1*0201 allele was associated with the development of either EOO‐JCA or CAU. Susceptibility to CAU was stronger when the DPB1*0201 was combined with the presence of DRB1*13. Another allele, DQB1*0301, was also associated with O‐JCA and CAU. Finally, no specific HLA class II allele was found to be related to the presence of ANA or psoriatic lesions or to the severity of the arthritis. Our findings suggest that the wide clinical and laboratory spectrum of JCA is associated with an immunogenetic background that is linked with HLA alleles of more than one locus. Some of them, such as the DPB1*0201 allele, confer susceptibility to certain clinical onsets and courses or complications of the disease. The rapidly advancing techniques of typing of DNA profiles may lead to more definite conclusions.
Alternatively spliced mRNA molecules of the thrombospondin receptor (CD36) in human PBMC
Authors: Kern P. , Kolowos W. , Hagenhofer M. , Frank C. , Kalden J. R. , Herrmann M.
Published: March 2003

We employed reverse transcription polymerase chain reaction (RT‐PCR) to detect alternatively spliced CD36 mRNA in human peripheral blood mononuclear cells (PBMC). Sequencing of cloned cDNA revealed alternatively spliced mRNA molecules in 13 out of 39 clones. We observed exon skipping of up to 10 out of 12 coding exons in eight alternative transcripts. Additionally, in five of the transcripts, alternative splice donor or acceptor sites were used during mRNA maturation. Considering the CD36 molecule serves many functions in coagulation, host defence, lipid metabolism, and scavenging, we speculate that the proteins encoded by the alternatively spliced mRNA molecules may be involved in regulation of both CD36 gene expression and function.
Intercellular adhesion molecule‐1 gene polymorphisms in Behçet’s disease
Authors: Verity D. H. , Vaughan R. W. , Kondeatis E. , Madanat W. , Zureikat H. , Fayyad F. , Marr J. E. , Kanawati C. A. , Wallace G. R. , Stanford M. R.
Published: March 2003

Intercellular adhesion molecule‐1 (ICAM‐1) gene polymorphisms have been implicated in the susceptibility to inflammatory diseases, including multiple sclerosis and inflammatory bowel disease. The expression of both soluble and tissue ICAM‐1 is increased in Behçet’s disease (BD) but the contribution of ICAM‐1 gene polymorphisms to this disease remains unknown. Associations with BD have been reported for genes within the MHC, including HLA‐B51, TNF and MICA, but the role of non‐MHC genes in BD remains largely unexplored. We have investigated the frequency of the R/G 241 and K/E 469 ICAM‐1 gene polymorphisms in 83 patients with BD disease and 103 healthy controls, all of Palestinian and Jordanian descent, and demonstrated an association between BD and the ICAM‐1 E469 allele (Pc = 0.046, OR = 2.1). Among patients, no association was found between the presence of ocular disease and ICAM‐1 polymorphisms. While the functional correlate of this polymorphism remains unclear, this finding indicates that a genetic polymorphism in the ICAM‐1 gene domain, which is independent of the MHC, may contribute to disease.
Analysis of a CD40 ligand dinucleotide microsatellite in multiple sclerosis
Authors: Dai Y. , Masterman T. , Huang W. , Hillert J.
Published: March 2003

In recent years, numerous reports have described the diverse roles of the CD40–CD40 ligand receptor–ligand pair. The interaction of these two cell‐surface molecules regulates both humoral and cell‐mediated immune functions. Because the CD40 ligand is known to be highly expressed on the peripheral blood mononuclear cells (PBMC) of multiple sclerosis (MS) patients, and because activated helper T cells expressing CD40 ligand have been found in the brain sections of MS patients, but not in those of normal controls, the protein is believed to be involved in MS development. We studied the influence of a polymorphic dinucleotide‐repeat marker located in the 3′ untranslated region of the X‐linked gene encoding CD40 ligand (CD40LG) on susceptibility to and disease severity in MS. From a total cohort of 771 Nordic definite‐MS patients, the most (n = 92) and least (n = 90) disabled octiles, as well as random samples of intermediately disabled males (n = 119) and females (n = 121), were genotyped; 135 ethnically matched healthy subjects were used as controls. In addition, the effect of the polymorphism on CD40 ligand mRNA expression was assessed using PBMC from 54 MS patients and 22 controls. The phenotype frequencies for the CD40LG marker did not differ significantly between gender‐conditioned intermediate‐MS subgroups and controls, or between gender‐conditioned disability octiles. Nor did the polymorphism appear to exert any significant effect on mRNA expression in either patients or controls.
Association between two tumour necrosis factor intronic polymorphisms and HLA alleles
Authors: Low A. S. , Azmy I. , Sharaf N. , Cannings C. , Wilson A. G.
Published: March 2003

The gene for tumour necrosis factor (TNF) lies at the telomeric end of the class III region of the major histocompatibility complex (MHC). Polymorphisms within this gene have been implicated in the genetic background of a large number of common human diseases. Recently two polymorphisms, TNF +489 and +691, have been described in the first intron of TNF (+489, G to A transition; +691, G deletion) and disease associations have been reported; however, the pattern of linkage disequilibrium with other MHC alleles has not been studied. We have therefore studied the association of TNF alleles with HLA‐DR, ‐DQ and ‐B alleles in 216 healthy individuals from the north of England. The frequencies of the uncommon alleles were 0.08 (+489A) and 0.05 (+691Gdel). The +489A allele is associated with carriage of DRB1*1104, DQB1*0301, B18 and B35. The +691Gdel allele is associated with carriage of DRB1*13 *11, DQB1*0301 and B44. Knowledge of the pattern of association, indicating probable linkage disequilibrium, between these TNF alleles may be useful in studies aimed at determining the role of this locus in the genetic background of the large number of diseases which show genetic associations with MHC haplotypes.