bluuebunny/crossref_metadata_2025 huggingface dataset:
Serum and urine markers of type I collagen metabolism in elderly women with high and low bone mineral density
Authors: CHENG S. , KOVANEN V. , HEIKKINEN E. , SUOMINEN H.
Published: November 2003

The serum markers of bone formation (carboxy‐terminal propeptide of type I collagen, PICP) and resorption (pyridinoline cross‐links containing telopeptide of type I collagen, ICTP), as well as urinary resorption markers, pyridinoline (Pyr) and deoxypyridinoline (Dpyr), were studied in 78‐year‐old women with high (n = 18) and low (n = 17) bone mineral density (BMD) measured from the calcaneus and tibia. The low‐BMD group had higher values for PICP (P = 0.025), Pyr (P = 0.001) and Dpyr (P < 0.001) than the high‐BMD group. No inverse relationship between these markers and BMD was, however, observed within the study groups. ICTP, Pyr and Dpyr correlated with each other in both groups and with PICP in the high‐BMD group. Higher levels of both the formation and resorption markers of type I collagen suggest an increased rate of bone turnover and remodelling in osteopenic elderly women.
Inhibited neutrophil functions in patients treated with nifedipine but not with verapamil or diltiazem
Authors: LEVY R. , NAGAUKER‐SHRIKER O. , SCHLAEFFER F.
Published: November 2003

Neutrophil functions were studied in patients receiving calcium channel blockers: nifedipine, diltiazem or verapamil. Neutrophils from patients treated with nifedipine showed a significantly lower superoxide generation stimulated by phorbol myristate acetate (PMA) (50 ng mL−1), opsonized zymosan (1 mg mL−1) or formyl‐methionyl‐leucyl‐phenylalanine (FMLP) (10−7 m), whereas superoxide generation by neutrophils of patients receiving diltiazem or verapamil showed only a slight and insignificant reduction compared with controls. Similarly, chemotaxis towards 10−7 m FMLP and phagocytosis were significantly lower in patients receiving nifedipine compared with controls and were only slightly reduced in patients receiving diltiazem or verapamil. Nifedipine was the most efficient drug in inhibiting the rise in intracellular calcium ion concentration ([Ca2+]i) when added in vitro and in neutrophils of patients receiving this drug, whereas verapamil had no significant effect. The correlation between the inhibitory effect of nifedipine on neutrophil function and the elevation of [Ca2+]i suggests that nifedipine inhibits neutrophil functions through its effect on [Ca2+]i. However, it is not the sole mechanism as superoxide generation induced by PMA, an agent that does not induce a rise in [Ca2+]i, is also inhibited. The unique effect of nifedipine in reducing neutrophil functions in vivo suggests its clinical implications concerning response to acute ischaemic myocardial events.
Regression speed of cardiac myosin heavy‐chain isozyme V3 in loaded right or left ventricle after relief of the load
Authors: IMAMURA S.‐I. , TAKAO A. , MATSUOKA R.
Published: November 2003

The authors examined whether there is any correlation between the regression speed of cardiac β (V3)‐myosin heavy‐chain (MHC) isozyme and duration of overload. The results showed that in the right ventricle of a 1‐week overloaded group, the loaded ventricular MHC isozyme V3 (29.0 ± 5.0%, P < 0.05) returned to the control level within 1 week after relief of overload (20.4 ± 4.2%, P = NS), whereas in a 3 week overloaded group (32.8 ± 5.3%, P < 0.05) it took 10 weeks (36.6 ± 8.6%, P = NS). The left ventricle showed the same tendency as the right ventricle. In sham‐operated rats, however, the changes in MHC isozyme V3 in the left ventricle were greater than those in the right ventricle. These results suggest that regression speed of the cardiac MHC isoform, changed by pressure overload, is accompanied by the duration of overload. Furthermore, the right and left ventricles may have different responsiveness to MHC isoform transitions in heart stresses.
Effect of cyproheptadine on episodic ACTH and cortisol secretion
Authors: Schürmeyer T. H. , Brademann G. , Von Zur Mühlen A.
Published: November 2003

To investigate the effect of cyproheptadine on ACTH and cortisol secretion, we obtained blood samples at 10‐min intervals for 24 h in six healthy volunteers under basal conditions and under treatment with 16 mg day−1cyproheptadine. Cyproheptadine caused significant decreases in mean plasma ACTH and cortisol levels in 30% and 19% of samples, respectively, mainly in the afternoon and evening. Analysis of episodic hormone secretion by three different methods demonstrated that the drug did not modulate the frequency but lowered the amplitudes of ACTH and cortisol secretory episodes. ACTH and cortisol responses following ovine CRH injection at 20.00 h were unchanged. We conclude that in the afternoon and evening central serotoninergic mechanisms influence the activity of the hypothalamic–pituitary–adrenal axis at the hypothalamic level by modulating the amplitude of the secretory hormonal bursts, but do not influence the increase in ACTH and cortisol secretion in the morning.
Quantitative analysis of HCV RNA and genotype in patients with chronic hepatitis C accompanied by oral lichen planus
Authors: Nagao Y. , Sata M. , Itoh K. , Tanikawa K. , Kameyama T.
Published: November 2003

Lichen planus (LP) is a common oral disorder that may represent a mucosal reaction to a variety of factors, including hepatitis C virus (HCV). To determine whether viral factors play a role in oral lichen planus (OLP) pathogenesis, we measured serum HCV RNA and determined HCV genotype in patients with chronic hepatitis C accompanied by OLP. The subjects included 43 patients with chronic hepatitis C: 23 with OLP (group 1) and 20 without OLP (group 2). Serum was collected from all subjects and used to quantify HCV RNA by the branched DNA signal amplification assay; HCV genotypes were classified by the reverse transcription–polymerase chain reaction (RT–PCR) method into types I, II, III and IV. Comparison of patient characteristics disclosed that the mean age of group 1, 60.7 years, was significantly higher (P=0.001) than that of group 2 (46.4 years). No significant differences were seen between sexes in values of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total protein (T protein), albumin and gamma‐globulin. There were also no significant differences in HCV RNA levels or HCV genotypes between groups. The findings suggested that OLP pathogenesis was a result of host factors rather than viral factors.
Association between eating behaviour and current glycaemic control, body mass or autonomic nervous function in long‐term type I and type II diabetic patients
Authors: Straub R. H. , Lamparter‐Lang R. , Palitzsch K.‐D. , SchÖlmerich J.
Published: November 2003

This cross‐sectional study was aimed at investigating the association between eating behaviour and current glycaemic control, body mass or autonomic nervous function in patients with type I and type II diabetes mellitus (DM). In 72 patients (31 type I DM, 41 type II DM) we investigated body mass index (BMI), serum cholesterol, serum triglycerides, haemoglobin A1c (HbA1c) and autonomic nervous function (seven standardized tests). The three‐factor eating questionnaire was used to investigate cognitive control of eating behaviour (CC) and susceptibility to eating problems (SEP). The mathematical product of CC and SEP provides information about disinhibition of eating control (DEC). In type I DM, there was a correlation between SEP and age (r=−0.536, P<0.01), SEP and duration (−0.441, P<0.05), SEP and HbA1c (0.438, P<0.05), and between DEC and duration (−0.371, P<0.05) and DEC and HbA1c (0.376, P<0.05). In type II DM, there was a correlation between SEP and BMI (0.401, P<0.01) and between DEC and BMI (0.429, P<0.01). Low CC was associated with autonomic nervous dysfunction in type I DM (P=0.022). In type II DM, autonomic nervous dysfunction was associated with high SEP (P=0.044). In conclusion, the correlation between eating behaviour and HbA1c or triglycerides in type I DM indicates that the questionnaire is able to address current parameters of diabetes control. Self‐assessment of eating behaviour in type I and type II diabetic patients reveals associations between eating behaviour and autonomic nervous function.
Human simple renal cyst fluid contains a cyst formation‐promoting activity for Madin–Darby canine kidney cells cultured in collagen gel
Authors: Taide M. , Kanda S. , Igawa T. , Eguchi J. , Kanetake H. , Saito Y.
Published: November 2003

Simple renal cysts are commonly observed in the elderly, but few examinations have been performed to study the mechanism of this disease. We have previously shown that simple renal cyst fluid contains some growth factors, including epidermal growth factor (EGF; less than 54pgmL−1) and insulin‐like growth factor I (IGF‐I; 30–2070pgmL−1) (M. Taide et al. Clin Chim Acta, 1993;217:199–203). In this report, the biological significance of growth factors or of human simple renal cyst fluid on the formation of renal epithelial cyst was determined using Madin–Darby canine kidney (MDCK) cells cultured in collagen gel. Both EGF (200pgmL−1 or more) and IGF‐I (100pgmL−1 or more) were found to stimulate cyst formation in MDCK cells. Additionally, 12/21 human simple renal cyst fluid samples were found to be capable of stimulating cyst formation in MDCK cells. This activity was due to a heat‐ and acid‐labile protein and not inhibited by the anti‐IGF‐I neutralizing antibody. These results indicate that in some instances simple renal cyst fluid would thus appear to contain specific activity for cyst formation, which may affect cyst formation in vivo
Cytokine profile in chronic cardiac failure
Authors: STEELE I. C. , NUGENT A.‐M. , MAGUIRE S. , HOPER M. , CAMPBELL G. , HALLIDAY M. I. , NICHOLLS D. P.
Published: November 2003

Elevated tumour necrosis factor α (TNF‐α) has been demonstrated in chronic cardiac failure (CCF) and may relate to severity of CCF and development of cachexia. We measured TNF receptor p55 in addition to TNF‐α in an attempt to improve the detection rate of TNF‐α activation, and simultaneously measured interleukin 6 (IL‐6), interleukin 8 (IL‐8) and C‐reactive protein. Thirty‐four patients with CCF and 24 control subjects were studied. Only TNF receptor p55 [6.95 (0.77−42.3) vs. 5.52 (1.50−13.36) ngmL−1 (median (range)] and IL‐6 [0.335 (0−9.79) vs. 0 (0−14.71) pgmL−1) were significantly elevated in patients compared with control subjects (both P<0.05). All inflammatory markers were more frequently elevated in patients, but none correlated with any of the clinical parameters studied. Reasons for inflammatory marker elevation in CCF are uncertain, but future studies should measure the p55 TNF receptor and IL‐6 in addition to TNF‐α, to improve detection of cytokine activity.
Immunosuppressive effects of endotoxins and bile acids in vivo in the rat
Authors: AOUAD K. , CALMUS Y. , NORDLINGER B. , MYARA A. , WEILL B. , POUPON R.
Published: November 2003

Cell‐mediated immunity is impaired during cholestasis. The aim of this study was to evaluate in vivo the effects on this immune defect of high serum levels of endotoxin and bile acids. Heterotopic cardiac allotransplantations were performed in the DA/Lewis rat combination. Cholestasis, induced by ligation/section of the common bile duct, was responsible for a significant delay in the rejection time (16 ± 0.5 vs. 7.1 ± 0.4 days in controls, P<0.01). Elimination of Gram‐negative intestinal bacteria from cholestatic rats by a vancocin/colimycin/tobramycin (VCT) mixture induced a significant reduction in endotoxin levels and a reduction in rejection times (9.5 ± 1.0 days, P<0.01) that remained, however, significantly longer than those of controls (P<0.05). Oral administration of chenodeoxycholic acid in non‐cholestatic rats significantly enhanced the serum concentration of total bile acids (60.6 ± 15.3 μmol L−1 vs. 17.4 ± 1.9 μmol L−1 in controls, P<0.01) and postponed allograft rejection (10.7 ± 0.6 days, P<0.01 vs. controls). These data suggest that increased endotoxin level and serum bile acid concentration may play a role in the immunosuppressive effect of cholestasis.
Subclasses of LpA‐I in coronary artery disease: distribution and cholesterol efflux ability
Authors: DECOSSIN C. , CASTRO G. , DERUDAS B. , BERTRAND M. , FRUCHART J.‐C. , FIÉVET C.
Published: November 2003

We analysed the distribution of LpA‐I particles according to their molecular weight in 34 men with symptomatic coronary artery disease (CAD) and 11 men with no symptoms of CAD (control group). Using an original rapid and reproducible gradient gel electrophoresis technique, three LpA‐I subclasses were defined: large (L‐LpA‐I), intermediate (I‐LpA‐I) and small LpA‐I (S‐LpA‐I). The proportion of L‐LpA‐I was significantly lower in the CAD group (37.5 ± 18.5%) than in the control group (58.9 ± 15.0%) (P < 0.01). Conversely, a significantly (P < 0.05) higher proportion of I‐LpA‐I (31.9 ± 20.7%) was observed in the CAD group compared with the control group (14.2 ± 8.2%). Also, in the CAD group, the proportion of L‐LpA‐I was positively associated with the plasma level of LpA‐I (P < 0.05) and, conversely, the proportion of S‐LpA‐I was negatively associated with LpA‐I levels (P < 0.01). L‐LpA‐I and I‐LpA‐I from CAD patients and from control subjects were most effective in promoting cholesterol efflux from Fu5AH rat hepatoma cells, whereas S‐LpA‐I was ineffective in this regard. In conclusion, the decreased ratio in CAD patients of L‐LpA‐I, lipoprotein subspecies that are required for cholesterol efflux from cells, suggests a potential anti‐atherogenic effect of these particles associated with the larger LpA‐I subfractions.
Medullary injury in the ageing rat kidney: functional–morphometric correlations
Authors: GREENFELD Z. , STILLMAN I. E. , BREZIS M. , ROSEN S.
Published: November 2003

Urinary concentrating ability decreases with age in both humans and animals. This phenomenon is not yet clearly explained or corroborated by morphological findings, often focused on glomerular changes. In rats aged 5–22 months, semi‐quantitative and quantitative morphometric analysis was performed to score cortical and medullary changes. Morphological data were related to renal functional parameters. Three stages of tubulointerstitial injury were observed: minimal findings (stage I); mild fibrosis with atrophy and casts in medullary thick ascending limbs (stage II); extensive fibrosis and atrophy with large cast formation (stage III). Maximal urinary osmolality decreased in correlation with the stage of tubulointerstitial injury (r = −0.8, P < 0.0001), from 3735 mosmol L−1 at stage I to 2807 at stage II and 1567 at stage III. A dissociation was observed in the rate of progression with age between tubulointerstitial injury and glomerular sclerosis. Whereas sclerosis was observed in only 2–3% of glomeruli at both stages I and II of tubulointerstitial injury, damage to thick ascending limbs significantly increased from 2% of tubules at stage I to 11% at stage II (P < 0.002). At stage III, both extensive glomerular sclerosis (53%) and tubular injury (32%) were present. Uninephrectomy accelerated both morphological injury and functional compromise. We conclude that, in the early stages of renal ageing, injury to medullary tubules may be more prevalent than injury to glomeruli and could be responsible for the reduction in concentrating ability.
Does hypercalcaemia or calcium antagonism affect human melatonin secretion or renal excretion?
Authors: WIKNER J. , WETTERBERG L. , RÖJDMARK S.
Published: November 2003

Patients with primary hyperparathyroidism have higher serum melatonin concentrations during active disease than after surgical cure. Whether this is caused by hypercalcaemia per se, increased parathyroid hormone secretion or other mechanisms is unknown. We decided to elucidate whether exogenous hypercalcaemia influences melatonin secretion. For this purpose, eight healthy volunteers were infused with calcium and saline on separate days and in random order (experiment A). Hypercalcaemia inhibited nocturnal melatonin secretion by 20% but left urinary melatonin excretion unaffected. If exogenous hypercalcaemia inhibits melatonin secretion, it is reasonable to assume that calcium channel blockers such as verapamil might have the opposite effect. This was investigated in experiment B, in which eight healthy subjects were treated on separate occasions with oral verapamil and placebo. Verapamil did not affect nocturnal melatonin secretion but increased melatonin excretion by 145%. As 6‐sulphatoxy‐melatonin is the main melatonin metabolite excreted by the kidneys, it was considered important to find out whether verapamil would also influence the excretion of 6‐sulphatoxy‐melatonin. This was investigated in experiment C, in which eight healthy volunteers were treated, on separate occasions, with oral verapamil and placebo. In this experiment also, verapamil increased urinary melatonin excretion significantly (by 67%), but left excretion of 6‐sulphatoxy‐melatonin unaffected. These findings imply that verapamil influences the renal and/or hepatic handling of melatonin.
Threonine allele in codon 54 of the fatty acid binding protein 2 gene does not modify the fatty acid composition of serum lipids in obese subjects
Authors: VIDGREN H. M. , SIPILÄINEN R. H. , HEIKKINEN S. , LAAKSO M. , UUSITUPA M. I. J.
Published: November 2003

Intestinal fatty acid binding protein (I‐FABP) participates in the metabolism of fatty acids in the intestinal enterocytes. Threonine encoding allele in codon 54 of the I‐FABP gene has been suggested as regulating the absorption of long‐chain fatty acids. We examined the fatty acid composition of serum lipid fractions and the concentration of serum free fatty acids after an overnight fast in obese subjects, aged 24–56 years, on their habitual diet. The body mass index of the subjects ranged from 29.7 to 43.3 kg m−2. Six subjects were homozygous for the Thr‐54 allele of the I‐FABP gene, 37 subjects were heterozygous for the Thr‐54/Ala‐54 allele and 24 subjects were homozygous for the Ala‐54 allele. We did not find any consistent differences in the proportions of long‐chain fatty acids in serum triglycerides, cholesterol esters or phospholipids, but the concentration of serum free fatty acids tended to be higher in subjects who were homozygous for the Thr‐54 allele (P = 0.13, for trend). In conclusion, our findings suggest that a polymorphism at codon 54 of the I‐FABP2 gene does not substantially modify the fatty acid composition of serum lipids in obese Finns.
Differentiation of BCS‐TC2 human colon adenocarcinoma cells by sodium butyrate: increase in 5′‐nucleotidase activity
Authors: NAVARRO J. M. , OLMO N. , TURNAY J. , LÓPEZ‐CONEJO M. T. , LIZARBE M. A.
Published: November 2003

We have analysed the major effects of sodium butyrate on the morphology, protein content and induction of epithelial differentiation markers in human colon adenocarcinoma BCS‐TC2 cells. Sodium butyrate alters the cell morphology, inducing a larger cellular size, flattening and vacuolization. The protein content per cell increases, whereas the proliferation rate is reduced. Moreover, cell death by apoptosis is also observed. Butyrate‐treated cells show higher levels of alkaline phosphatase activity and carcinoembryonic antigen, suggesting that this agent induces the in vitro differentiation of BCS‐TC2 cells. These effects are reversible and time and dose dependent. In addition, we have observed that the ectoenzyme 5′‐nucleotidase activity also increases during this treatment, suggesting that it could be considered as a new differentiation marker for this type of carcinoma cells. These results contribute to the understanding of the action of sodium butyrate as a potential cancer chemotherapeutic agent.
Lipoprotein lipase gene polymorphisms in ischaemic stroke and carotid stenosis
Authors: HUANG P. , KOSTULAS K. , HUANG W.‐X. , CRISBY M. , KOSTULAS V. , HILLERT J.
Published: November 2003

Ischaemic stroke is pathogenetically heterogeneous, but there is strong evidence that genetic as well as environment factors contribute to the risk of the individual. Here we report the similar distribution of polymorphic markers of the lipoprotein lipase (LPL) gene in 128 patients with ischaemic stroke, 56 patients with carotid artery stenosis and 95 healthy control subjects, in spite of a significant influence of the Asn291→ Ser mutation on serum levels of triglycerides. We conclude that these LPL polymorphisms do not contribute greatly to the overall risk of ischaemic stroke in the general population.
Serum levels of parathyroid hormone are related to the mortality and severity of illness in patients in the emergency department
Authors: CARLSTEDT F. , LIND L. , WIDE L. , LINDAHL B. , HÄNNI A. , RASTAD J. , LJUNGHALL S.
Published: November 2003

Hypocalcaemia is a common finding in intensive care patients. In addition, raised levels of parathyroid hormone (PTH) have been described. The explanation and clinical importance of these findings are yet to be revealed. To investigate the occurrence of hypocalcaemia and elevated PTH levels and their relationship to morality and the severity of disease, serum levels of PTH, ionized calcium (Ca2+) and the cytokines interleukin 6 (IL‐6) and tumour necrosis factor alpha (TNF‐α) were measured on arrival in the emergency department in a broad spectrum of 140 acutely ill patients patients suffering from common diseases such as stroke, acute abdominal disorders, obstructive lung diseases, heart failure, acute myocardial infarction, angina pectoris, trauma and infectious diseases. A score (APACHE II) was calculated to assess the severity of disease. Elevated PTH levels (> 55 pg mL−1) were seen in 16% of the patients, being most frequent in patients with myocardial infarction (28%) and congestive heart failure (42%). The levels were significantly correlated with the APACHE II score (r = 0.48, P < 0.0001) and with the length of stay in hospital (r = 0.26, P < 0.002). PTH was also significantly (P < 0.03) elevated in non‐survivors compared with survivors and was found to be a stronger predictor of mortality (P < 0.01) than the APACHE II score (P < 0.02) in Cox's proportional hazard analysis. No close relationships were found between the cytokine levels and the indices of calcium metabolism. In conclusion, a rise in serum levels of PTH was common and related to the severity of disease and mortality in a mixed emergency department population.
Suppression of the nocturnal free fatty acid levels by bedtime cornstarch in NIDDM subjects
Authors: AXELSEN M. , LO¨NNROTH P. , ARVIDSSON LENNER R. , SMITH U.
Published: November 2003

The aim of the present study was to examine the effects of a large dose of slow‐release carbohydrates (CHOs) at bedtime on the nocturnal glucose, insulin and free fatty acid (FFA) levels, and to assess the putative effects on morning fasting and post‐prandial glucose levels in patients with moderately controlled non‐insulin‐dependent diabetes mellitus (NIDDM). Unheated cornstarch (106 g of CHO) or a mixed equicaloric meal (58 g of CHO) was given at 22.00 hours to 10 NIDDM patients. For comparison, the patients were also given a smaller mixed meal at 22.00 hours on a third occasion (17 g of CHO). Compared with the mixed meals, cornstarch led to a slightly elevated early‐morning plasma insulin level and a suppression of the nocturnal FFA level (P < 0.05), as well as to a reduced incremental glucose level (IAUC) after breakfast the next morning by approximately 30% (P < 0.05). There was a significant and linear relationship between the nocturnal FFA level and the glucose IAUC after breakfast (r = 0.44, P < 0.02), indicating that the effect may have been mediated by the suppressive effect of cornstarch on nocturnal lipolysis. In summary, bedtime intake of unheated cornstarch in NIDDM subjects is associated with a suppression of the nocturnal FFA levels and a reduced glucose IAUC after breakfast. As the treatment did not improve overall glucose control, studies of the effects of an individually titrated amount of cornstarch are proposed to further explore the putative favourable effects of bedtime cornstarch in the treatment of NIDDM.
Mapping the soil resources of a recent alluvial plain in Greece using fuzzy sets in a GIS environment
Authors: Kollias V. J. , Kalivas D. P. , Yassoglou N. J.
Published: November 2003

Collecting soil data is time‐consuming and costly, often exceeding practical possibilities. A methodology for the delineation of soil mapping units in an alluvial plain of Western Peloponnese, Greece, was investigated. A detailed soil survey of an area of 300 ha was used to obtain the basic soil data for evaluating the performance of the proposed methodology. The methodology consists of the following steps: (a) data collection from borings and representative soil profiles, (b) definition of the soil mapping units in the study area, (c) determination of the range of the diagnostic variables for each mapping unit from field observations and statistical analysis of the analytical data from representative soil profiles, (d) determination of the class of each diagnostic variable by observation at a network of boring points, (e) subjective assignment of numerical values to soil variables at the bore points, (f) estimation of the values of each soil variable at the points of a regular grid using the interpolation methods kriging and inverse squared distance, (g) application of the fuzzy set theory to the interpolated data and the production of thematic fuzzy maps, and (h) validation of the results through a number of independent test borings. The results obtained show that the proposed methodology can produce soil maps of recent alluvial plains with acceptable accuracy and cost.
Submicroscopy and stable isotope geochemistry of carbonates and associated palygorskite in Iranian Aridisols
Authors: Khademi H. , Mermut A. R.
Published: November 2003

Pedogenic carbonates in arid and semi‐arid regions of the world have a great significance as palaeoecological and palaeoclimatological indicators and form a major pool in the carbon cycle. We analysed the ultra‐microfabric and the stable isotope composition of C and O in pedogenic carbonates in colluvial soils derived from limestone in an arid region of central Iran. Our objective was to determine the conditions for the formation of soft pedogenic carbonate nodules and their co‐existence with palygorskite in the palaeo‐argillic horizon. Scanning electron microscopy revealed that the calcite aggregates were matted with palygorskite. Ultra‐microtome cuts, examined using transmission electron microscopy, provided more detailed information about the fundamental particle association of secondary carbonates and palygorskite. Although less abundant, other silicate clays were detected in both the acid‐insoluble clay fractions and in ultra‐cuts, mostly in fine clay size, suggesting the engulfing of palygorskite by growing calcite or illuviation of palygorskite during or after formation of the calcite. Coatings of illuvial clays on calcite crystals support the hypothesis that palygorskite was trapped by pedogenic carbonate when the climate was wetter than it is today to form an argillic horizon. However, electron microscopic evidence of the occurrence of fibres on the immediate pedogenic carbonate particle surfaces suggests the in situ formation of palygorskite. The δ13C and δ18O values of pedogenic carbonates suggest that these carbonates were formed in an environment with more available moisture and more C4 plants than now.
A conserved region in the σ54‐dependent activator DctD is involved in both binding to RNA polymerase and coupling ATP hydrolysis to activation
Authors: Wang Ying‐Kai , Lee Joon H. , Brewer John M. , Hoover Timothy R.
Published: November 2003

Rhizobium melioti DctD activates transcription from the dctA promoter by catalysing the isomerization of closed complexes between σ54‐RNA polymerase holoenzyme and the promoter to open complexes. DctD must make productive contact with σ54‐holoenzyme and hydrolyse ATP to catalyse this isomerization. To define further the activation process, we sought to isolate mutants of DctD that had reduced affinities for σ54‐holoenzyme. Mutagenesis was confined to the well‐conserved C3 region of the protein, which is required for coupling ATP hydrolysis to open complex formation in σ54‐dependent activators. Mutant forms of DctD that failed to activate transcription and had substitutions in the C‐terminal half of the C3 region were efficiently cross‐linked to σ54 and the β‐subunit of RNA polymerase, suggesting that they bound normally to σ54‐holoenzyme. In contrast, some mutant forms of DctD with amino acid substitutions in the N‐terminal half of the C3 region had reduced affinities for σ54 and the β‐subunit in the cross‐linking assay. These data suggest that the N‐terminal half of the C3 region of DctD contains a site that may contact σ54‐holoenzyme during open complex formation.
Enhanced T Lymphocyte Expression of LFA‐1, ICAM‐1, and the TNF Receptor Family Member OX40 in HgCl2‐Induced Systemic Autoimmunity
Authors: ROOS A. , CLAESSEN N. , WEENING J. J. , ATEN J.
Published: November 2003

Injection of mercuric chloride into Brown Norway (BN) rats induces a T lymphocyte‐dependent autoimmune syndrome. In order to investigate whether modification of adhesion and costimulatory molecules on T lymphocytes may be involved in early T lymphocyte activation by HgCl2, the authors analysed expression of these molecules in peripheral lymph node cells from BN rats at day 4 after injection of HgCl2. Tri‐colour flow cytometry was performed for expression analysis within CD45RC‐defined subsets of CD4+ and CD8+ cells. Compared to control rats, HgCl2‐exposed rats showed increased numbers of lymphocytes, especially of T lymphocyte blast cells. The levels of LFA‐1 expression as well as the fractions of ICAM‐1+ cells were significantly increased in all CD45RC‐defined subsets of CD4+ and CD8+ cells. Within the CD4+CD45RClo T lymphocyte population, HgCl2‐injected rats showed a highly significant increase in the number of cells expressing OX40, which is a member of the TNF receptor family. Moreover, only CD4+CD45RClo blast cells of HgCl2‐exposed rats showed decreased expression of CD43, increased expression of CD49d and decreased numbers of CD26+ cells. The results indicate that induction of autoimmunity by HgCl2 in BN rats is associated with altered expression of T lymphocyte costimulatory molecules, predominantly on CD4+CD45RClo cells, which may be caused by a direct effect of HgCl2 on these cells, and may precipitate further activation of T and B lymphocytes by HgCl2
T‐Cell Receptor Diversity Expressed by CD4+ T Cells Activated by Primary Allogeneic HLA‐DR Stimulation: Estimation of the Degree of CDR3 Diversity
Authors: ONDA K. , KASHIWAGI N. , OBATA F.
Published: November 2003

In order to analyse the diversity of T‐cell receptors (TCRs) expressed by the T‐cell population activated by allogeneic HLA‐DR stimulation, TCRβ cDNA was synthesized from mRNA of human CD4+ T cells that had been stimulated in a primary mixed lymphocyte reaction (MLR). The TCRβ cDNA was amplified by the polymerase chain reaction (PCR), subjected to bacterial cloning, and sequenced from Vβ through Jβ. Twenty‐six different Vβ genes and 10 different Jβ segments were detected among 56 randomly selected cDNA clones. Occurrences of Vβ17.1 and Jβ1.5 were higher than those found in the CD4+ T‐cell population activated with a CD3‐specific antibody. A total of 53 different CDR3 sequences, two of them occurring more than once, were detected among the 56 cDNA clones. In order to estimate the degree of CDR3 diversity, amino acid similarity in the CDR3 region of the cDNA was calculated and compared with those of the anti‐CD3‐activated T‐cell sequences as well as those of various published T‐cell clone sequences, each directed to either alloantigens or single antigenic peptides. It was found that the similarity score among CDR3 sequences obtained from the MLR (56.4 ± 10.3) was comparable to those of anti‐CD3‐activated T cells (55.7 ± 10.7) and those of T‐cell clones directed toward alloantigens (range, 48.4 ± 12.4−59.4 ± 13.1), but significantly smaller than those of T‐cell clones directed toward single antigenic peptides such as those derived from myelin basic protein (75.6 ± 17.9) and cytochrome c (76.9 ± 20.5). These results provide quantitative proof that TCRs of T cells activated by primary allogeneic HLA‐DR stimulation have a larger diversity than those recognizing single antigenic peptides.
Identification and Characterization of Specific Receptor for Interleukin‐8 from the Surface of Human Monocytes
Authors: BISHAYI B. , SAMANTA A. K.
Published: November 2003

A specific receptor for interleukin‐8 has been identified on the surface of human monocytes using 125I IL‐8 as a probe. A binding kinetic pattern shows that saturation was attained after 90 min and that the receptor was distinct from the receptors of other cytokines (IL‐1α, IL‐2, TNFα, GMCSF) and FMLP. Scatchard analysis of the binding data shows that 7000–10,000 receptors/monocyte are present with an equilibrium Kd 7 × 10−9 M. By immunoblot, the receptor for IL‐8 showed a sharp band with approximate M.W. 59 kD, consistent with the M.W. of IL‐8 receptor of neutrophils. In Boyden Chamber, monocytes migrated towards IL‐8 and the cytokine was observed to induce transient rise of intracellular Ca++ in the cells. Thus, identification of functionally active IL‐8 receptor in monocyte may be helpful for understanding its possible role during inflammation.
Establishment and Characterization of RAG‐2 Deficient Non‐Obese Diabetic Mice
Authors: SÖDERSTRÖM I. , BERGMAN M.‐L. , COLUCCI F. , LEJON K. , BERGQVIST I. , HOLMBERG D.
Published: November 2003

The authors have established a new immunodeficient mouse strain on the genetic background of the diabetes prone non‐obese diabetic (NOD) mouse. A deletion mutant of the RAG‐2 gene was back crossed 10 generations onto the NOD/Bom strain background. The homozygous NODrag−2−/− mice lack functionally mature B and T lymphocytes and do not develop insulitis or diabetes throughout life. In contrast, heterozygous NODrag−2+/− develop both insulitis and diabetes with an incidence similar to the wild type NOD mice. In transfer experiments, spleen cells from diabetic NOD donors were found to transfer disease to NODrag−2−/− recipients similar to what has been previously observed in transfer to irradiated NOD recipients or to immunodeficient NOD‐scid/scid mice. While resembling the recently established NOD‐scid/scid mice in many respects, the NODrag−2−/− mice represents an advantageous model for reconstitution of the pathogenesis of murine IDDM as it does not produce any endogenous, mature T or B lymphocytes.
Inhibition of Immunoglobulin Production In Vitro by IgG and F(ab′)2 Fragments, but not by the Fc Portion
Authors: KLAESSON S. , TAMMIK L. , MARKLING L. , LUNDKVIST I. , RINGDÉN O.
Published: November 2003

Antibody‐secreting B cells were measured as plaque‐forming cells (PFC) in a modified haemolysis‐in‐gel assay, using protein A coupled sheep erythrocytes as targets. Human lymphocytes from blood (PBL), bone marrow or spleen were stimulated in vitro by various polyclonal B‐cell activators and incubated with intravenous immunoglobulin (IVIG) or peptide fragments of IVIG. IgG and IgM production from PBL and bone marrow cells, measured as PFC, was inhibited more than 50% by IVIG 2.5mg/ml, compared to controls without IVIG. Inhibition of the IgG and IgM response of spleen cells by IVIG varied depending on the stimuli. Using Staphylococcus aureus protein A (SPA), inhibition was almost 90% (P<0.001). The inhibition of the IgG and IgM responses to lipopolysaccharide from Escherichia coli (LPS) were 70% (P<0.01) and 28% (P<0.05), respectively. IgG stimulation by pokeweed mitogen (PWM) was inhibited by 57% (P<0.01), but the IgM response was inhibited only by the higher IVIG concentration of 5.0mg/ml. In mixed lymphocyte cultures of spleen cells, IgG and IgM production were inhibited by more than 60% (P<0.05). The effect of IgG, IgG‐F(ab′)2 and IgG‐Fc on LPS or PWM‐stimulated spleen cells were compared, using equimolar concentrations of the various preparations. IgG‐ and IgM‐producing PFC were significantly (P<0.05) inhibited in a dose‐dependent fashion by IgG and F(ab′)2, but not by Fc. LPS‐induced IgG and IgM production was inhibited also when IgG and F(ab′)2 were added up to 48h after the stimulator. A comparison of IgG, F(ab′)2 and Fc products from different companies showed that all IgG and F(ab′)2 preparations significantly inhibited IgG and IgM production of LPS‐stimulated spleen cells. No significant inhibition was obtained with any of the purified Fc products.
Multiple Levels of MHC Class I Down‐Regulation by ras Oncogenes
Authors: LOHMANN S. , WOLLSCHEID U. , HUBER C. , SELIGER B.
Published: November 2003

A number of tumours and oncogene transformed cells displayed reduced MHC class I surface expression which seemed to enable their escape from immune surveillance. To test whether oncogenic activation is directly involved in suppressing MHC class I expression, a model of inducible oncogene expression was chosen. Mouse fibroblasts transfected with different oncogenes expressed under the control of the dexamethasone‐inducible MMTV promoter were analysed in the presence and absence of hormone for the mRNA and protein expression of MHC class I molecules as well as the respective oncogenes. Immunofluorescence analyses demonstrated an inverse association of MHC class I and oncogene expression after dexamethasone stimulation, independent of the type of oncogene causing transformation. Hormone‐mediated induction of oncogene expression caused down‐regulation of all H‐2 loci. Kinetic experiments using MMTV c‐Ha‐ras(A) transfectants revealed that down‐regulation of MHC class I surface expression was preceded by a dexamethasone‐induced change of morphology, anchorage‐independent growth, and an increase of the ras protein p 21. Parallel monitoring of mRNA expression demonstrated a time‐dependent up‐regulation of ras specific transcripts, which was associated with differential regulation of MHC class I heavy and light chain transcripts. β2‐microglobulin transcripts were transiently suppressed, whereas MHC class I heavy chain transcripts remained unaffected. To investigate the mechanisms of oncogene‐mediated down‐regulation of MHC class I expression, H‐2 promoter transfections and a nuclear run on assays were performed. In MMTV c‐Ha‐ras(A) cells, neither alterations of the H‐2 promoter activity nor of the transcriptional activity of H‐2 antigens was observed in the presence of dexamethasone, whereas both could be up‐regulated by interferon‐γ treatment. These data suggest that oncogene‐mediated transformation is directly associated with MHC class I down‐regulation, but that complex interactions affecting MHC class I heavy and light chain genes at the transcriptional and/or post‐transcriptional level are involved in this process.
Experimental AA‐Amyloidosis in Mice is Inhibited by Treatment with the Anti‐Rheumatic Drug Tenidap
Authors: HUSEBEKK A. , STENSTAD T.
Published: November 2003

In a mouse model for induction of experimental AA‐amyloidosis, treatment with tenidap was shown to inhibit the development of amyloidosis. Studies have shown that the drug inhibits the cytokines interleukin (IL)‐6, IL‐1 and tumour necrosis factor α (TNF‐α) which are known to stimulate hepatocytes to synthesize acute phase proteins (APPs). The APP serum amyloid protein (SAA) is the precursor for amyloid protein AA and tenidap treatment reduces the serum levels of SAA in mouse and humans. It is suggested that reduction of SAA levels reduces the risk of AA fibril formation and thus the development of amyloidosis.
In Vivo Activation of T‐Cell Induction into the Primed Phenotype and Programmed Cell Death by Staphylococcal Enterotoxin B
Authors: AROEIRA L. S. , MORENO M. C. , MARTINEZ‐A C.
Published: November 2003

The authors demonstrate that SEB immunization activates Vβ8+ T cells and induces the acquisition of the primed phenotype as defined previously by low MEL‐14 and high Pgp‐1 expression. SEB‐activated spleen CD4+ and CD8Vβ8+ T cells have different population dynamics and regulate the expression of MEL‐14 and Pgp‐1 differentially, suggesting that the SEB‐MHC class II complex preferentially activates CD4Vβ8+ T cells. Interestingly, at day 3 after SEB immunization, Vβ8+ T cells expressing low, but not high, levels of MEL‐14 undergo apoptosis, indicating that T‐cell activation is a prerequisite for triggering programmed cell death. These results might help to trace antigen‐reactive cells to the activated or primed pool, as well as to identify those cells which will undergo programmed cell death.
Peptide Antibiotics: Holy or Heretic Grails of Innate Immunity?
Authors: BOMAN H. G.
Published: November 2003

In the last 2 years (1994–95), two symposium volumes and three reviews have been published that were fully devoted to peptide antibiotics (antibacterial peptides or antimicrobial peptides). Since the field has been growing rapidly, this review is largely a follow‐up of new results published in the last 2 years. Sequencing of the 16S RNA of the small ribosomal subunit indicate that the microbial world is much larger than generally appreciated. The importance of the natural flora is stressed and its effect on the evolution of peptide antibiotics and immunity in general is discussed.
Augmented Antigen Presentation by Mouse Ia+ T Clone Cells BK‐BI–2.6.O4.1 Mediated by Transferrin Receptors
Authors: TSCHOETSCHEL U. , MCCOY K. L. , RESKE‐KUNZ A. B.
Published: November 2003

The murine T clone cells BK‐BI–2.6.O4.1 (BI/O4.1) synthesize and express MHC class II molecules constitutively. BI/O4.1 cells are able to present various protein antigens to antigen‐specific CD4+ T cells. However, a 10‐fold higher concentration of antigen is needed to activate specific T cells to lymphokine secretion by BI/O4.1 cells in comparison with spleen cells or with the more homogeneous population of bone marrow‐derived macrophages (BMMph). The authors tested whether the reduced antigen presentation potential of BI/O4.1 cells was augmented by transferrin‐ mediated uptake of the model antigen ovalbumin (OVA) coupled to human ferric transferrin. It was shown that 240‐fold less OVA was sufficient to induce proliferation of an OVA‐specific T‐cell clone when the conjugate and not native OVA was used. The presence of ferric TF in the cultures competitively inhibited this effect of the conjugate. A similar shift in the dose–response curve to lower doses of antigen was induced by the conjugate when B lymphoma cells were used as antigen‐presenting cells. BMMph and P388D1 cells processed and presented the conjugate with similar efficiency as native OVA, although both cell types exposed transferrin receptors. These data suggest that the reduced antigen presentation potential of BI/O4.1 T clone cells is due to the inefficient uptake of OVA by pinocytosis and delivery into the processing compartment.
Molecular Characterization of MPT83: a Seroreactive Antigen of Mycobacterium tuberculosis with Homology to MPT70
Authors: HEWINSON R. G. , MICHELL S. Ll. , RUSSELL W. P. , MCADAM R. A. , JACOBS JR W. R.
Published: November 2003

The Mycobacterium bovis antigens MPB70 and MPB83 are homologous cross‐reactive proteins. It has been reported previously that MPB83 is glycosylated and exists in two forms with apparent molecular masses of 23 kDa and 25 kDa, whereas the apparent molecular mass of MPB70 is 22 kDa. Using a monoclonal antibody, SB10, which recognizes an epitope common to both MPB70 and MPB83, we compared the expression of these proteins in M. bovis BCG, virulent M. bovis and virulent Mycobacterium tuberculosis by Western blotting of bacterial lysates. The previously described pattern of high and low producing substrains of BCG for MPB70 was also applicable for MPB83. Virulent M. bovis was found to express high levels of MPB70 and MPB83. Immunoblotting experiments using sera from Balb/c mice infected with live M. tuberculosis H37Rv revealed that although the MPB83 homologue of M. tuberculosis, MPT83, is expressed at low levels in M. tuberculosis when grown in vitro, the protein is highly immunogenic during infection with live bacteria. A clone from a mycobacterial shuttle cosmid library of M. tuberculosis H37Rv was isolated which expressed both MPT70 and MPT83. Genetic analysis of this cosmid revealed that MPT70 and MPT83 were encoded by separate genes with the gene encoding MPT83 situated 2.4 kb upstream of mpt70. Both genes are transcribed in the same direction. The gene encoding MPT83 was cloned and DNA sequencing revealed an open reading frame of 660 bp encoding a protein with a predicted molecular mass of 22 kDa. Recombinant MPT83 was expressed in Escherichia coli from the native AUG initiation codon by translational coupling. In E. coli MPT83 was expressed as a 23 kDa antigen whereas in the rapid growing mycobacterium Mycobacterium smegmatis the protein was expressed as a 25 kDa protein indicating post‐translational modification of the protein by M. smegmatis. In recombinant M. smegmatis MPT83 was predominantly cell associated whereas MPT70 was secreted into the culture medium. Amino acid sequence comparison between MPT83 and MPT70 revealed a 61% identity between the proteins, although little homology was apparent at the amino terminus. In MPT83 this region contained a typical lipoprotein signal peptide cleavage motif and a putative signal motif for O glycosylation. Both these motifs were absent from the amino acid sequence of MPT70.
Different Percentages of Peripheral Blood γδ+ T Cells in Healthy Individuals from Different Areas of the World
Authors: ESIN S. , SHIGEMATSU M. , NAGAI S. , EKLUND A. , WIGZELL H. , GRUNEWALD J.
Published: November 2003

The frequency of γδ+ T cells in the peripheral blood of 26 Turkish, 24 Swedish, 35 Japanese and 14 ‘Asian’ (non‐Japanese) healthy blood donors and healthy volunteers were investigated by flow cytometry. In the Turkish group, 9.3% (median value) of the CD3+ peripheral blood T cells expressed the γδ T cell receptor. A similar level of γδ+ T cells was found in the non‐Japanese ‘Asian’ healthy volunteers (9.2%), while significantly lower values were detected in the Swedish (4.2%) and Japanese (4.5%) groups. These dramatic differences in normally occurring γδ+ T cells in different groups of healthy individuals were further reflected by a low incidence of >10% γδ+ T cells in the Swedish (0/24) and Japanese (6/35) groups compared to the Turkish (12/26) and ‘Asian’ (5/14) groups. The described γδ+ T cell differences between distinct ethnic groups are thus likely to be a consequence of environmental factors, but additional genetic influences cannot be ruled out. The present study demonstrates the potential importance of the ethnic origin and environmental history of subjects examined in studies of γδ+ T cells–disease relations.