Search

Introduction: Hypertension and hyperperfusion of the pulmonary vascular bed in the setting of congenital cardiac malformations may lead to progressive pulmonary vascular disease. To improve the understanding of the basic mechanisms of this disease, there is a need for clinically relevant animal models which reflect the disease process. Material and Results: We randomly allocated 45 newborn pigs, at the age of 48 hrs, to groups in which there was either construction of a 3 mm central aorto-pulmonary shunt, undertaken in 9, or ligation of the left pulmonary artery, achieved in 13. Controls included sham operations in 13, or no operations in 10 pigs. Follow-up was continued for three months. The interventions were compatible with survival in most pigs. The shunts resulted in an acute 85% increase in systolic pulmonary arterial pressure, and a more than twofold increase in pulmonary blood flow. By three months of age, nearly all shunts had closed spontaneously, and haemodynamics were normal. Ligation of the left pulmonary artery resulted in a normal total pulmonary blood flow, despite only the right lung being perfused, and a 33% increase in systolic pulmonary arterial pressure. These haemodynamic changes were maintained throughout the period of study. In both groups, histomorphometry revealed markedly increased muscularity of the intra-acinar pulmonary arteries. Circulating levels of endothelin were normal in the shunted animals, and elevated in those with ligation of the left pulmonary artery. Conclusion: In neonatal porcine models of pulmonary vascular disease, created by construction of 3 mm central aorto-pulmonary shunts and ligation of one pulmonary artery, we observed histopathological changes of the pulmonary vasculature similar to early hypertensive pulmonary vascular disease in humans. Elevated circulating levels of endothelin were associated with abnormal haemodynamics rather than abnormal pathology. These findings could be valuable for future studies on the pathogenesis of hypertensive pulmonary vascular disease associated with congenital cardiac malformations.

The purpose of this study was to evaluate the potential ability of magnetic resonance imaging (MRI) for evaluation of myocardial iron deposits. The applied MRI technique has earlier been validated for quantitative determination of the liver iron concentration. The method involves cardiac gating and may, therefore, also be used for simultaneous evaluation of myocardial iron. The tissue signal intensities were measured from spin echo images and the myocardium muscle signal intensity ratio was determined. The SI ratio was converted to tissue iron concentration values based on a modified calibration curve from the liver model. The crucial steps of the method were optimized; i.e. recognition and selection of the myocardial slice for analysis and positioning of the regions of interest (ROIs) within the myocardium and the skeletal muscle. This made the myocardial MRI measurements sufficiently reproducible. We applied this method in 41 multiply transfused patients. Our data demonstrate significant positive linear relationships between different iron store parameters and the MRI-derived myocardial iron concentration, which was significantly related to the serum ferritin concentration (ρ = 0.62.P < 0.0001) and to the MRI-determined liver iron concentration (ρ = 0.36,P = 0.02). The myocardial MRI iron concentrations demonstrated also a significant positive correlation with the number of blood units given (ρ = 0.45,P = 0.005) and the aminotransferase serum concentration (ρ = 0.54,P = 0.0008). Our data represents indirect evidence for the ability of MRI techniques based on myocardium/muscle signal intensity ratio measurements to evaluate myocardial iron overload.

Background Methotrexate (MTX) -induced liver damage is an important complication in patients treated with this drug for skin disease. Reliable non-invasive monitoring tests would have considerable importance. Objectives This retrospective study was designed in order to evaluate if serial normal serum levels of amino-terminal propeptide of type III procollagen (PIIINP) might indicate that no significant fibrosis is taking place in the liver, and thereby reduce the need for repeated liver biopsies in psoriatic patients treated with MTX. Methods The clinical records of 70 patients with psoriasis, who in the years 1989/90 were on MTX and had both a liver biopsy without fibrosis and a normal PIIINP, were examined and followed until the patient stopped taking the drug. The follow-up time was from 1 to 11 years. Results A total of 189 liver biopsies and 329 analyses of PIIINP were recorded. Twenty-one patients had only one and no further biopsies, but their data included at least two to three PIIINP samples obtained within a year around the time of the biopsy, and at least two were taken either prior to or at the time of the biopsy. The remaining patients had from two to seven liver biopsies each and a total of 267 analyses of PIIINP. In the study period only four patients developed fibrosis of the liver as shown by liver biopsies, and all four of these patients developed elevated serum PIIINP levels. In addition two further patients, one of them with psoriatic arthritis, had elevated PIIINP, but normal liver biopsy. Thus no liver fibrosis was missed in the 63 patients with consistently normal PIIINP levels. Conclusions Present data support the view that, as long as PIIINP is consistently normal in serial investigations, there is minimal risk of development of substantial liver fibrosis.

Osteoprotegerin (OPG), the neutralizing decoy receptor for the osteoclast activator RANK ligand, was measured in serum taken from patients with multiple myeloma at the time of diagnosis. Median OPG was lower in the patients with myeloma (7.4 ng/mL; range, 2.6-80; n = 225) than in healthy age- and sex-matched controls (9.0 ng/mL; range 5.1-130; n = 40; P = .02). Importantly, OPG levels were associated with degree of radiographically assessed skeletal destruction (P = .01). The median OPG level in patients lacking osteolytic lesions was 9.1 ng/mL, as compared with 7.6 ng/mL and 7.0 ng/mL, respectively, in patients with minor or advanced osteolytic disease. Furthermore, OPG levels were associated with World Health Organization performance status (P = .003) and correlated to serum levels of carboxy-terminal propeptide of type I procollagen (PICP; P

Rejnmark L, Vestergaard P, Heickendorff L, Andreasen F, Mosekilde L (Aarhus University, Aarhus, Denmark). Effects of thiazide- and loop-diuretics, alone or in combination, on calcitropic hormones and biochemical bone markers: a randomized controlled study (Original study). J Intern Med 2001; 250: 144–153. Objective. Diuretics are commonly used drugs that in addition to their effect on the cardiovascular system also affect calcium homeostasis and bone metabolism. We evaluated the effects of loop diuretics (LD) and thiazide diuretics (TD) on calcitropic hormones and biochemical bone markers. Design. A total of 50 postmenopausal women were randomized to 7 days of treatment with either the TD bendroflumethiazide, the LD bumetanide, bendroflumethiazide plus bumetanide, or placebo. Blood and urine (24 h) were sampled on each day. Statistical inferences were made versus the concomitant changes in the placebo group. Results. Bendroflumethiazide increased the tubular reabsorption of calcium (TRCa) (+0.46 ± 0.11%, P=0.009), plasma levels of parathyroid hormones (PTH) (+24 ± 10%, P=0.06), and 1,25(OH)2D (+12 ± 6%, P=0.03). Bumetanide decreased the TRCa (–0.5 ± 0.1%, P=0.01) and increased plasma PTH and 1,25(OH)2D levels (+27 ± 9%, P=0.02 and +36 ± 12%, P=0.006, respectively). Treatment with either of the drugs did not alter plasma calcium, osteocalcin, bone alkaline phosphatase (bone-ALP) or urinary NTx/creatinine ratio. However, treatment with both drugs caused an increased plasma calcium level (+2.7 ± 1.0%, P=0.007) and decreased plasma levels of bone-ALP (–21 ± 3%, P=0.001), osteocalcin (–6 ± 3%, P=0.03), and urinary NTx/creatinine ratio (–39 ± 6%, P=0.001). Conclusion. Calcium homeostasis and bone metabolism are to a major degree influenced by diuretic treatment. Surprisingly, LD and TD exerted a similar effect on calcitropic hormones despite their opposite effects on the renal calcium excretion. In clinical practice, treatment with diuretics has to be considered as a cause of parathyroid stimulation.

Changes in skeletal remodeling (biochemical bone markers) and regional bone mineral density (spine, hip, and forearm bone mineral density [BMD]) were observed for 3 years in 20 patients (15 women and 5 men; age 54 +/- 11 years, range 29-69 years) after successful surgery for primary hyperparathyroidism (PHPT). Fifteen PHPT patients were compared with 15 normal controls who were exactly matched with respect to age, gender, and menopausal status (10 women and 5 men; age 53 +/- 12 years, range 29-65 years [PHPT] and 29-66 years [controls]). All bone markers (serum osteocalcin, bone alkaline phosphatase, and type I collagen telopeptide [ICTP], and urinary hydroxyproline and NTx/creatinine ratio) declined significantly and reached normal levels within 6 months. No major changes took place during the remaining 2.5 years, apart from urine hydroxyproline, which disclosed a small peak around 12 months with a further decline towards study end (p < 0.05). Bone mineral density increased significantly in all regions (p < 0.001). At all locations, except the intertrochanteric region of the hip, the increase continued from 6 months until study end (p < 0.05). The increase in BMD was unequally distributed among regions (p < 0.001). The increase at the proximal forearm was less than in the spine (p < 0.05), the trochanteric region of the hip (p < 0.05), and the distal forearm (p < 0.05). No difference in BMD increase was observed between men, and pre- and postmenopausal women. Compared with the matched control group, PHPT patients had significantly lower BMD at baseline in the proximal (p < 0.02) and distal (p < 0.05) forearm. Furthermore, during the 3-year follow-up period, the PHPT patients showed a significant increase in BMD compared with controls in the spine (p < 0.005), the trochanteric and intertrochanteric regions of the hip (p < 0.005 and p < 0.05, respectively), and the distal forearm (p < 0.005). In conclusion, bone remodeling is normalized within the first 6 months after successful parathyroid surgery, with no major changes during the following 2.5 years. Bone mineral density increases at both cancellous and cortical sites, but in predominantly cortical bone, the recovery in BMD is less than in cancellous bone-rich areas.

Changes in bone remodeling and bone mineral density were observed during a period of 6 months after surgery in 24 patients with primary hyperparathyroidism (20 women and 4 men; age 54 ± 12 years, range 26-69 years). All bone markers declined significantly within the 6 month follow-up period, but the time course for changes in renal N-terminal telopeptide of type 1 collagen (NTx) excretion differed from those of the other markers by a steep and significant reduction (p

In order to investigate whether soluble intercellular adhesion molecule-1 (sICAM-1) and soluble interleukin-2 receptors (sIL-2R) were present in scleroderma skin, and to compare their levels to concentrations measured in plasma and clinical parameters, we examined suction blister fluid and plasma from 13 patients with systemic sclerosis and 11 healthy volunteers. Suction blisters and biopsies were from the transition zone between normal skin and scleroderma, and uninvolved abdominal skin. The levels of sICAM-1 and sIL-2R were significantly increased in both plasma and suction blister fluid from systemic sclerosis patients compared with healthy volunteers. ICAM-1 was localized to vessels and perivascular mononuclear infiltrates by immunohistochemical methods. IL-2R was expressed by CD3-positive cells. The elevated levels of sICAM-1 and sIL-2R in suction blister fluid point towards activation of endothelial cells and T cells in both the transition zone and uninvolved skin of systemic sclerosis patients.

Simple bone marrow fibrosis is seen in 10-30% of multiple myeloma (MM) patients. We investigated the incidence and characteristics of the bone marrow stromal alterations, in order to characterize the collagens involved by immunohistochemistry, and to evaluate the use of serum aminoterminal propeptide of type III procollagen (PIIINP) as a marker of marrow fibrogenesis and disease activity in MM. 34 consecutive patients with newly diagnosed MM were included prospectively, and followed for 12-30 months. Compared with the findings in 15 normal individuals we found increased interstitial deposits of collagen III in 48% of MM patients, whereas deposits of collagen I were not increased. Interstitial fibrosis appeared to be restricted to areas of severe plasma cell infiltration, but it could also have a more dispersed presentation in the severely infiltrated marrow. There was a high co-distribution of collagen III fibrils and reticulin fibres. Serum PIIINP levels were elevated in most patients, and in the follow-up study serum PIIINP showed a good correlation with the response to treatment. Patients with resistant or progressive disease had continually elevated levels of PIIINP. In most patients with responsive disease serum PIIINP normalized, and we observed no relapses in patients who had normal serum PIIINP levels. Other patients who responded to treatment by reduced M-component level, but had persistently elevated serum levels of PIIINP, had either early relapses or developed progression of osteolytic lesions in spite of unchanged M-component levels. Therefore an elevated serum PIIINP during treatment might indicate an active malignant clone. Serum PIIINP does not simply follow the M-component, but gives further information of potential therapeutic value.

Long-term follow-up data are presented on changes in peripheral blood counts and Hb requirements of 11 patients with myelodysplastic syndromes (MDS) during iron chelation treatment with desferrioxamine for up to 60 months. The erythroid marrow activity was indirectly evaluated by repeated determinations of the serum transferrin receptor concentration. The efficacy of iron chelation was evaluated by repeated quantitative determination of the liver iron concentration by magnetic resonance imaging. Reduction in the Hb requirement ( > or = 50%) was seen in 7/11 (64%) patients. Five patients (46%) became blood transfusion independent. Platelet counts increased in 7/11 (64%) patients and the neutrophil counts in 7/9 (78%) evaluable patients. All patients in whom iron chelation was highly effective showed improvement of erythropoietic output accompanied by an increase in the serum transferrin receptor concentration. It is concluded that reduction in cytopenia in MDS patients may be accomplished by treatment with desferrioxamine, if the iron chelation is efficient and the patients are treated for a sufficiently long period of time. Exactly how treatment with desferrioxamine works remains a challenge for further investigation.

Patients with severe iron overload may develop hepatic fibrosis due to iron toxicity. Unfortunately, the follow-up of the fibrogenic activity during treatment by histological examination of tissue biopsies carries potential side effects, and may therefore not be justified ethically. Recently, the serum concentration of procollagen type III peptide (S-PIIINP) has been shown to be a valid serum marker of the activity of collagen metabolism in conditions with hepatic fibrosis unrelated to iron overload. In order to evaluate the potential usefulness of this test in patients with fibrosis due to iron overload, we investigated the relationship between the PIIINP serum concentration and the size of iron overload in 18 patients with hereditary haemochromatosis (HH) and in 14 patients with transfusional iron overload. A close correlation was found between S-ferritin and S-PIIINP (r = 0.73, p < 0.0001). Follow-up of 6 patients during iron depletion treatment revealed a normalization of the serum aminotransferase concentration before normalization of S-PIIINP was found. This may indicate that excess iron directly induces an increase in fibrogenesis rather than the increased fibrogenesis is secondary to hepatocellular injury caused by iron excess. Thus, serial measurements S-PIIINP may be useful in follow-up of the fibrogenic process due to iron overload.

Topical glucocorticosteroids are widely used in the treatment of children with atopic dermatitis. Due to percutaneous absorption, these agents may become systemically available and cause inhibition of growth in children. However, the mechanisms responsible for the growth-suppressive effective are not fully understood.To evaluate whether treatment with topical budesonide has any adverse effects on growth-hormone-dependent serum levels of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3), and on the serum markers of bone and collagen turnover osteocalcin, the carboxy-terminal propeptide of type I collagen (PICP), the carboxy-terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP) and the amino-terminal propeptide of type III procollagen (PIIINP).13 children (mean age 9.5 years) with atopic dermatitis were studied in an open longitudinal trial with run-in and budesonide treatment periods of 2 weeks' duration. During the run-in, only emollient was used. During the treatment period, budesonide cream 0.025% followed by emollient were applied twice daily all over the body except on the face. At day 14 of each period, blood samples were taken and eczema was scored according to a severity index based on extent and activity of the disease.Compared to the run-in, budesonide treatment was associated with a statistically significant reduction in mean severity index (p = 0.002). No statistically significant effects on serum levels of IGF-I, IGFBP-3, osteocalcin or ICTP were observed. The serum concentrations of PICP and PIIINP were reduced with (mean +/- 1 SD) 43 +/- 64 milligrams (95% confidence interval 3.5-80 milligrams, p = 0.03, t = 2.4, d.f. = 12) and 1.2 +/- 1.5 milligrams (95% confidence interval 0.3-2.1 milligrams, p = 0.01, t = 3.0, d.f. = 12), respectively.Type I and III collagen turnover may be suppressed during short-term treatment with topical budesonide in children with atopic eczema. clinical implications need further study.

The present study was performed to evaluate whether information concerning synthesis and degradation of type I collagen in multiple myeloma (MM) as obtained by serum analyses of C-terminal propeptide of type I procollagen (PICP) and the C-terminal telopeptide of type I collagen (ICTP) may be useful in evaluating the development of osteolytic bone destruction. Serum N-terminal propeptide of type III procollagen (PIIINP) may give information about marrow fibrosis in MM. No data are available about MM and serum hyaluronan, another important component of bone marrow stroma. We examined 15 consecutive patients before treatment and 15 sex- and age-matched controls. We found highly significant elevations in serum ICTP (median 6.2 vs. 2.4 micrograms/L; P < 0.01), PIIINP (median 5.2 vs. 2.9 micrograms/L; P < 0.01) and hyaluronan (median 122 vs. 45 micrograms/L; P < 0.01). ICTP in serum correlated closely to bone morbidity (r = 0.69; P < 0.01). Furthermore, serum ICTP correlated highly significantly to serum PIIINP (P < 0.01) and serum beta 2-microglobulin (P < 0.01), whereas there was no correlation between hyaluronan and any of the collagen-derived peptides or beta 2-microglobulin. The MM group was followed for 9-25 months and analysis of survival data suggested that serum ICTP may be of predictive value (P < 0.05). We conclude that important changes in connective tissue metabolism occur in MM. ICTP in serum seems to be a noninvasive marker of bone morbidity and may be of prognostic value. Furthermore, elevation of hyaluronan in serum is common in MM, the significance of which is unknown.

1. 1. Sulphate labelled proteoglycans (PG) synthesized by cultured human arterial smooth muscle cell have been quantified using an improved method based on a combination of specific enzymes and ethanol precipitation. 2. 2. The present method gives quantitative data of PGs and subclasses allowing batchwise analysis of a large number of samples. 3. 3. Approximately 81 % ± 1.7% (mean ± SD, n = 6) of total PGs synthesized by human arterial smooth muscle cells accumulated in medium. 4. 4. In cell layer and medium chondroitin sulphate proteoglycan constituted 65.0% ± 0.3% and 75.8% ± 0.7% (mean ± SD, n = 3), respectively of sulphated PGs. 5. 5. Heparan sulphate proteoglycan accounted for 26.8% ± 0.6% in cell layer and 22.6% ± 0.5% (mean ± SD, n = 3) in medium of sulphated PGs.

New serum and urine markers of type I and type III collagen turnover have recently been introduced in children. These markers include the formation markers of type I collagen turnover, serum N-terminal (PINP) and C-terminal (PICP) propeptides of type I procollagen, and serum N-terminal propeptide of type III procollagen (PIIINP), as well as the resorption markers serum cross-linked C-terminal telopeptide of type I collagen (ICTP) and urine cross-linked N-telopeptides of type I collagen (Ntx) and deoxypyridinoline (DPD) (1)(2)(3)(4)(5). The aim of the present study was to assess diurnal variations in serum PINP, PICP, ICTP, PIIINP, and urine DPD and Ntx in children. Two boys and five girls 10.4–14.4 years (mean, 12.2 years) were studied. One boy and three girls were in puberty. Height SD scores varied from −2.5 to 2.2 (mean, 0.6) and weight SD scores from −1.4 to 1.0 (mean, −0.4). The study was approved by the local ethics committee, and informed consent was obtained from all children and their parents. The first sample was urine collected from 2400 to 0800 on the morning of the day of investigation. Thereafter, urine was collected in 4-h intervals until …

Levels of serum aminoterminal propeptide of type III procollagen were measured in 170 patients with psoriasis (49% with coexistent psoriatic arthritis) who had liver biopsies performed during or before treatment with methotrexate or, in some cases, with retinoids. Psoriasis patients with fibrosis or cirrhosis in their liver biopsy specimens had a significantly higher mean serum aminoterminal propeptide of type III procollagen than did patients without fibrosis and without arthritis. Only 4% of patients without cirrhosis or fibrosis and no arthritis had an elevated serum aminoterminal propeptide of type III procollagen. In contrast, 38% of patients with psoriatic arthritis had an increased aminoterminal propeptide of type III procollagen in the absence of detectable liver fibrosis. It is concluded that the number of liver biopsies performed on methotrexate-treated psoriasis patients with or without arthritis may be reduced to a minimum as long as serum aminoterminal propeptide of type III procollagen is normal. Increased serum aminoterminal propeptide of type III procollagen in the absence of arthritis is a strong indicator of liver fibrogenesis and suggests the need for liver biopsy to monitor possible methotrexate-induced toxicity. In patients with psoriatic arthritis an increased aminoterminal propeptide of type III procollagen may be related to the joint disease. Patients with psoriatic arthritis and increased levels of aminoterminal propeptide of type III procollagen should therefore follow the established guidelines for the use of methotrexate in psoriasis.

Reprint requests: Thomas Ledet, MD, Research Laboratory for Biochemical Pathology, Aarhus Kommunehospital, DK-8000, Aarhus C, Denmark. The problem of cardiovascular disease and diabetes mellitus can be subdivided into one distinct zone where large-scale research work has provided a number of well documented pieces of information from epidemiologic and clinical studies, and another, large and indeterminate grey region of unasked questions and unposed problems, which is inhabited by borderline problems between diabetes and cardiovascular research. The epidemiologist has told us that heart disease occurs 3-5 times more frequently among diabetic patients. At present, it is not possible to explain this very high frequency as a consequence of the usual risk factors in atherosclerosis, such as increased serum LDL.’ Likewise, various experimental investigations have not been able to provide an explanation through analyses of non-enzymatic glycosylated lipoproteins.* In our laboratory, the study of large vessel disease in diabetes mellitus is guided by a hypothesis that postulates the existence of a diabetic macroangiopathy which develops independent of the usual atherosclerotic risk factors, but is a result of diabetic intermediary metabolism and endocrinopathy.3s4 Since deposition of a strong PAS-positive substance in the wall of the smaller blood vessels is a characteristic feature of diabetic microangiopathy, we decided to investigate the extent of this PAS-positive substance in the larger coronary arteries from a group of NIDDM patients.5 The data obtained from the diabetic patients were compared with the results from a group of age and gender matched nondiabetic subjects. An area of the tunica media was selected, based on the presence or absence of atherosclerotic plaques in the tunica intima. Using a traditional point counting procedure, we estimated the area occupied by the PAS-positive material in the tunica media. It appeared that a significantly larger area was occupied by the PAS-positive substance in the coronary arteries from diabetic individuals than was the case in nondiabetics. Moreover, it appeared that the size of the PAS-positive area was completely independent of the presence of atherosclerotic plaques (Figure 1). The same pattern was observed when the amount of collagen was evaluated using a histologic staining technique and the same point counting. In other histologic sections taken from the same samples of the coronary arteries, the area occupied by acid mucopolysaccharides (glycosaminoglycans) was evaluated by identification with alcian blue, again with the point counting procedure. It could be shown that the area containing acid mucopolysaccharides was substantially reduced in coronary arteries from diabetic patients, independent of the presence of atherosclerotic plaques. The basement membrane in the tunica media is a PAS-positive structure surrounding individual arterial smooth muscle cells.6s7 Since the basement membrane is abnormal in many organs in diabetic patients, we have focused on the elaboration of that structure in a tissue culture system of rabbit aortic smooth muscle cells. Using normolipemic fasting serum from a group with IDDM and a group with NIDDM, we have evaluated the elaboration of basement membrane, and found that sera from the diabetic patients significantly enhanced the accumulation of basement membrane material compared with sera from normolipemic nondiabetic individuals of the same age and gender (Figure 2).* In the same culture system, we tested the effect of hyperlipemic serum obtained from rabbits fed a high cholesterol diet for more than 6 weeks, but found no influence on basement membrane accumulation.

To the Editor. —We have read with interest the article "Treatment of Systemic Sclerosis With Extracorporeal Photochemotherapy" by Rook and coworkers1in the March 1992 issue of theArchives. By no means do we question their results, but we find that we are obliged to express some words of caution, as it is our experience that patients with the severe progressive form of the disease may not all be sufficiently controlled by photopheresis alone. This, at least, applies to patients who have more pronounced symptoms from organs other than the skin. For 5 to 8 months we have used photopheresis to treat eight patients with severe systemic sclerosis. We planned to treat all patients for at least 8 months, but, due to severe exacerbations, it was necessary to give additional immunosuppressive therapy to four patients. Two of these patients, together with another patient, wanted to discontinue photopheresis after 5

The influence of insulin in physiological concentrations on basement membrane (BM)-like material from arterial smooth muscle cells was studied in cell cultures. BM-like material was isolated from the cell layer by a sonication-differential centrifugation technique after a 24-h incubation period with insulin and [3H]leucine added to the culture medium. Insulin in concentrations of 50, 100, 200 and 500 mU/l was found to exert no influence on incorporation of amino acids into BM-like material. Neither glucose, 16 mmol/l, ketones, 1 mmol/l, nor glucagon 100 ng/l were able to induce altered accumulation of BM-like material. The effect of insulin on the carbohydrate units of BM-like material was studied by concanavalin A-Sepharose chromatography of glycopeptides and by analyses of neutral hexoses and amino sugars. The result showed that insulin, 200 mU/l, induced a shift in composition of neutral sugars by decreasing the amount of galactose relative to glucose and mannose. No changes in glycopeptide binding to the concanavalin A-sepharose column were observed. The results indicate that insulin induces only minor alterations in BM-like material of arterial smooth muscle cells and that the changes apparently are restricted to the carbohydrate units.

Summary In this chapter we have presented information on the development of large vessel damage in diabetes mellitus. A series of changes occur independent of the presence of atherosclerosis. The abnormalities include accumulation of PAS-positive material, laminin, fibronectin, type IV collagen and connective tissue with lack of acid mucopolysaccharides, and deposition of calcium. It is of particular interest that accumulation of PAS-positive material and lack of acid mucopolysaccharides are recognized as the histological markers of diabetic microangiopathy. These changes are in agreement with the hypothesis of a non-atherosclerotic large vessel damage, that is, diabetic macroangiopathy. From this standpoint the working hypothesis of a specific diabetic macroangiopathy should generate new ways to study the mechanism of the large vessel disease of diabetes over and above the traditional concept of classical atherosclerosis.

As determined by native polyacrylamide gel electrophoresis (PAGE) and gel chromatography the molecular mass of native tumor necrosis factor (TNF)-alpha was approximately 35 kDa. When incubated at low concentrations (less than 1 nM) 125I-labeled TNF-alpha and unlabeled TNF-alpha rapidly multimerized or dissociated into monomers and bioactivity decreased. Sodium dodecyl sulfate (SDS)-PAGE analysis of cross-linked 125I-labeled TNF-alpha demonstrated bands of multi- and trimeric TNF-alpha in addition to dominating bands of dimers and monomers. Tri-, di- and monomeric TNF-alpha were recovered from SDS-PAGE gels and allowed to renature. Of the original receptor-binding activity, 10%-15% was obtained with cross-linked TNF-alpha dimers, whereas none was recovered from preparations of trimeric TNF-alpha. Multimeric and monomeric TNF-alpha exhibited little or no binding activity, and cell-bound, cross-linked TNF-alpha which was dissociated from cellular binding sites was mainly dimeric. 125I-labeled TNF-alpha bound to lymphokine-activated killer (LAK) cells and binding kinetics were much similar (Kd approximately 100 pM) to those reported in other normal cell types. The number of receptors per LAK cell was approximately 4 x 10(3). Cross-linking of TNF-alpha to binding sites in U-937 and LAK cells yielded a receptor-ligand complex of about 80/90 kDa. At 37 degrees C, 125I-labeled TNF-alpha was rapidly internalized and degraded in L-929, U-937 and LAK cells. Degradation of ligand and recycling of receptors were blocked in the presence of methylamine. Methylamine significantly inhibited TNF-alpha-mediated cytolysis of L-929 cells and caused a quantitatively corresponding reduction in cellular TNF-alpha uptake, indicating that L-929 lysis was mediated by receptors.

1. 1. The intra- and extracellular distribution of fibronectin and laminin was studied by immunofluorescence in cultures of rabbit and human arterial smooth muscle cells. 2. 2. Basement membrane (BM)-like material was isolated from the cell layer of arterial smooth muscle cells cultures and analysed by sodium dodecyl sulphate gel electrophoresis (SDS-PAGE) and immunoblotting. The major 220–240 kD component of arterial BM-like material was identified as fibronectin. Also a 200 kD fibronectin band was observed. 3. 3. The 200 kD subunit of laminin was contained in isolated BM-like material, but no slower migrating laminin chains were detected. 4. 4. Collagens were prepared from pepsinized BM-like material. The band pattern as resolved by SDS-PAGE and silver staining suggested that type IV collagen is the major collagen of arterial BM-like material.

The biomechanical properties of aortic samples from patients with Type 1 (insulin-dependent) diabetes mellitus and age- and sex-matched control subjects were analysed using a materials testing machine. The specimens were prepared from tissue outside areas of visible atherosclerosis in order to discriminate between primary Type 1 diabetic alterations in the aortae and secondary changes due to increased atherosclerosis. We paid special attention to the correction of biomechanical parameters for differences in wall thickness and registration of specimen length values. In the Type 1 diabetic aortae a marked reduction was found in the extensibility and an increase in their stiffness. The reduced extensibility was correlated significantly to the duration of Type 1 diabetes. The pronounced alterations in the mechanical properties could not be explained by the increase in the wall thickness which was observed among the Type 1 diabetic patients and the alterations could not be correlated to the grade of atherosclerosis in the thoracic aorta. The results of the present study, therefore, strongly suggest that Type 1 diabetic patients develop alterations in the arterial connective tissue independent of the presence of atherosclerosis. Such primary alterations in the vessel wall may play a role in the pathogenesis of large vessel disease among these patients.

Udgivelsesdato: 1997-Jul OBJECTIVE: To optimise the indication and time for operation for abdominal aortic aneurysm (AAA), we analysed whether or not serum-elastin-peptides (SEP) could be a potential predictor for expansion. MATERIALS AND METHODS: Four thousand, four hundred and four 65-73-year-old males were invited for screening to detect an AAA. Three thousand, three hundred and thirty-four attended (76%). One hundred and forty-one had AAA, and 19 > 5 cm in diameter were referred for immediate operation. The remaining 122 AAA were offered an annual follow-up. Ninety-nine were later asked for a blood-sample, 83 attended. SEP was determined using an ELISA-technique. The observer was blinded to the SEP result. RESULTS: The average expansion was 2.6 mm/year, and 10 (8.1) were referred for operation because of a diameter of > 5 cm. SEP were positively correlated to expansion (R = 0.4, F = 14.65). In multiple regression analyses, AAA size, SEP, beta-agonist-treatment, and FEV1, but not beta-blockers, were predictors of expansion. SEP remained a relatively strong predictor (F = 13.13). CONCLUSIONS: Serum-elastin-peptides seem to predict expansion, but a larger, longer study is needed to establish clinical recommendations.

Oligosaccharides from myomedial basement membrane-like material were characterized in respect of size, attachment to protein and charge heterogeneity after metabolic labelling with [ 3 H]glucosamine. Arterial basement membrane-like material was isolated from cultures of aortic myomedial cells by a sonication-differential centrifugation technique. Glycopeptides were then obtained by proteinase digestion and Sephadex G-50 chromatography. Alkaline borohydride treatment of the glycopeptides followed by Sephadex G-25 chromatography revealed that 10–14 % of the oligosaccharides were released by a β-eliminative reaction. The molecular weight of the alkali labile carbohydrate units was estimated to be approximately 750. Alkali stable oligosaccharides were released from the glycopeptides by hydrazinolysis. The liberated oligosaccharides were retarded by Sephadex G-50 chromatography corresponding to a molecular weight of 2700 using unit β thyroglobulin oligosaccharides as standard. The chromatographic pattern obtained by anion exchange chromatography of the glycopeptides after neuraminidase treatment showed that a major part of the glycopeptides contain one or more sialic acid residues, but also other negatively charged groups -possibly phosphomannosyl residues were present as suggested by [ 32 PO 4 3- ] labelling and concanavalin-A-Sepharose chromatography. Concanavalin-A-Sepharose chromatography combined with a- mannosidase treatment and gel filtration suggested that a minor part of the glycopeptides were of high-mannose- type.

Udgivelsesdato: 2008-null There is limited information about the in-hospital plasma profile of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with non-ST-elevation acute coronary syndrome (NSTACS) and furthermore, the prognostic influence of the timing of NT-proBNP measurements in NSTACS is unsettled. These subject matters are elucidated in this study composed of 455 patients with NSTACS (symptoms

Objective: Our objective was to investigate the effect of pioglitazone on bone mineral density (BMD) and bone turnover markers in polycystic ovary syndrome (PCOS). Design and Setting: We conducted a randomized, placebo-controlled study at an outpatient clinic at a university hospital. Patients: Thirty premenopausal patients with PCOS and 14 age- and weight-matched healthy females participated. Interventions: Pioglitazone (30 mg/d) or placebo was given for 16 wk. Main Outcome Measures: Measurements of BMD [hip (neck and total) and lumbar spine (L2–L4)], bone metabolic parameters [alkaline phosphatase (ALP), 25-hydroxyvitamin D, C-telopeptide of type I collagen (ICTP), osteocalcin, and PTH], endocrine profiles (testosterone, estradiol, and insulin), and body composition (waist to hip ratio, body mass index, and whole-body dual-energy x-ray absorptiometry scans) were performed. Results: Patients with PCOS had significantly higher levels of ICTP, fasting insulin, and testosterone than controls, whereas no differences were measured in ALP, PTH, body composition, or BMD. Pioglitazone treatment was followed by reduced BMD [geometric means (−2 to +2 sd)]: lumbar spine 1.140 (0.964–1.348) vs. 1.127 (0.948–1.341) g/cm2 (average decline 1.1%) and femoral neck 0.966 (0.767–1.217) vs. 0.952 (0.760–1.192) g/cm2 (average decline 1.4%), both P < 0.05. Both ALP and PTH decreased significantly during pioglitazone treatment, whereas no significant changes were measured in 25-hydroxyvitamin D, ICTP, osteocalcin, sex hormones, and body composition. Conclusion: Pioglitazone treatment was followed by decreased lumbar and hip BMD and decreased measures of bone turnover in a premenopausal study population relatively protected from bone mineral loss.

Udgivelsesdato: 1998-Aug PURPOSE: To study the relation between abdominal aortic aneurysms and chronical obstructive pulmonary disease (COPD), in particular the suggested common elastin degradation caused by elastase and smoking. METHODS: A cross-sectional population study and a prospective cohort study of small abdominal aortic aneurysms was performed in a community setting. All previous diagnoses recorded in a hospital computer database were received for 4404 men 65 to 73 years of age who had been invited to a population screening for abdominal aortic aneurysm. One hundred forty-one men had AAA (4.2%). They were asked to participate in an interview, a clinical examination, and collection of blood sample. Men with an abdominal aortic aneurysm 3 to 5 cm in diameter were offered annual ultrasound scans to check for expansion. RESULTS: Among patients with COPD 7.7% had abdominal aortic aneurysms (crude odds ratio=2.05). The adjusted odds ratio, however, was only 1.59 after adjustment for coexisting diseases associated with abdominal aortic aneurysm (P=.13). The mean annual expansion was 2.74 mm per year among patients with COPD, 2.72 among patients without COPD, and 4.7 mm among patients who used oral steroids compared with 2.6 among patients who did not use steroids (P < .05). Concentration of serum elastin peptide and plasma elastase-alpha1-antitrypsin complexes correlated negatively with forced expiratory volume in the first second (FEV1) among patients with COPD. However, multivariate regression analysis showed that concentration of serum elastin peptide, therapy with beta-agonists, and FEV1 correlated positively with degree of expansion but that concentration of plasma elastase-alpha1-antitrypsin complexes and serum alpha1-antitrypsin did not influence expansion, suggesting that elastase plays an important role in the pathogenesis of COPD but not of abdominal aortic aneurysm. CONCLUSION: The high prevalence of abdominal aortic aneurysm among patients with COPD is more likely to be caused by medication and coexisting diseases rather than a common pathway of pathogenesis.