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L Risteli

Publications and source records attributed to L Risteli.

At least 109 records · Page 6Linked to original sources

Serum osteocalcin and carboxyterminal propeptide of type I procollagen in rheumatoid arthritis.

OBJECTIVES: Previous reports indicate that serum osteocalcin (serum bone GLA protein (S-BGP)) and carboxyterminal propeptide of type I procollagen (PICP) can be used as indicators of bone formation and turnover. The purpose of this study was to assess the activity of bone formation in patients with rheumatoid arthritis (RA) using S-BGP and S-PICP. The biochemical data were compared with data obtained from bone histomorphometry. METHODS: Concentrations of S-BGP and S-PICP were measured in 119 women with RA aged 30-66 years and 47 healthy female controls matched for age. Bone histomorphometry of iliac crest samples was performed in 107 patients with RA. RESULTS: Weak to moderate correlations between the serum markers and histological bone formation parameters were found. Concentrations of S-BGP and S-PICP were significantly decreased in patients with RA compared with the controls (S-BGP 7.2 (2.3) v 8.7 (2.1) micrograms/l; S-PICP 105 (32) v 117 (38) micrograms/l. The lowest values were found in patients with recent onset RA. CONCLUSIONS: These findings suggest that bone formation and bone remodelling are generally reduced in patients with RA.

Adult↗

Clinical characteristics and circulating collagen and laminin metabolites in insulin-dependent diabetic children with joint and skin manifestations.

One hundred seventy-four children and adolescents with insulin-dependent diabetes mellitus were examined for joint contractures and skin manifestations in their hands. Joint contractures were found in 52 (29.8%) and skin manifestations in 29 (16.6%) patients. To eliminate the possible confounding effects of age and duration of diabetes on the variables to be studied, patients younger than 7 y and with a duration of diabetes shorter than 3 y were excluded from the subsequent analyses. Of the remaining 108 children, those with joint contractures had lower serum concentrations of the 7-S domain of type IV collagen and the P1 fragment of laminin than the other patients (p = 0.033) but higher mean glycated Hb levels (p = 0.048). A clear association was noted between the occurrence of joint contractures and skin changes (p = 0.007). Background retinopathy was found in six patients (5.6%), three of whom had stage II joint contractures (p = 0.064). The children with skin changes and those with combined joint and skin manifestations more often had insulin-dependent diabetes mellitus in their first-degree relatives (p = 0.038 and p = 0.043, respectively). No difference in relative height was found between the groups. No association could be seen between disease susceptibility antigens in the HLA-D locus and joint or skin manifestations. The lower levels of circulating collagen and laminin metabolites in the diabetic children with joint contractures suggest that these patients are characterized by a reduced turnover of basement membranes in tissues.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Markers of type I and type III collagen synthesis in serum as indicators of tissue growth during pregnancy.

The concentrations of the carboxy-terminal propeptide of type I procollagen (PICP) and the amino-terminal propeptide of type III procollagen (PIIINP) in serum were followed prospectively as indicators of synthesis of the respective collagens in 266 healthy primiparas during the second and third trimesters of pregnancy. The PIIINP concentration increased 2-fold during the third trimester; the median value was 10.0 micrograms/L at gestational week 40, with a range from 4.6-32.7 micrograms/L (reference interval for nonpregnant women, 1.7-4.2 micrograms/L). A significant increase also took place in the PICP concentration. The frequency distributions of the two parameters were near normal at week 26. They started to broaden out at week 32 and were wide at week 38. In severe preeclampsia, PIIINP tended to increase more than in normal pregnancies of the same duration. The increase in PIIINP correlated significantly with maternal weight gain and the birth weight of the infant, but not with other parameters related to pregnancy or delivery. At gestational week 38, there was a significant correlation between the circulating concentrations of insulin-like growth factor-I and PIIINP or PICP, but not between human placental lactogen and PICP, and only a weak association between human placental lactogen and PIIINP. This suggests that insulin-like growth factor-I is involved in the regulation of type I and type III collagen synthesis during pregnancy.

Adolescent↗

Possible variation in bone resorption during the normal menstrual cycle.

In order to determine whether bone turnover varies during the normal menstrual cycle, we measured biochemical markers of bone resorption (serum pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (sICTP), fasting urinary hydroxyproline/creatinine, fasting urinary pyridinoline/creatinine and fasting urinary deoxypyridinoline/creatinine) and bone formation (plasma osteocalcin, serum carboxy-terminal propeptide of type I procollagen and serum alkaline phosphatase) in ten healthy premenopausal women every two or three days for a complete menstrual cycle. A cyclic pattern was detected in sICTP, with its nadir during the follicular phase and its peak during the luteal phase, and an overall variation of 17% during the menstrual cycle (p = 0.004). No cyclic changes were observed in the urinary parameters of bone resorption or in the biochemical markers of bone formation. We conclude that sICTP, a new biochemical marker of bone resorption, undergoes small variations during a normal menstrual cycle in premenopausal women, whereas the biochemical markers of bone formation remain constant.

Adult↗

Effects of systemic isotretinoin on serum markers of collagen synthesis and degradation.

In the present investigation, collagen synthesis and degradation were studied by measuring the carboxyterminal propeptide of type I procollagen (PICP), the aminoterminal propeptide of type III procollagen (PIIINP) and a type I collagen-specific degradation peptide (ICTP) in the sera of 43 male patients, treated for acne with isotretinoin or with tetracycline. The values were compared with those observed in 24 acne patients without treatment and in healthy controls. The treatment with isotretinoin did not seem to affect these parameters in a cross-sectional setting, whereas tetracycline treatment was associated with slightly decreased levels of ICTP. Since there were marked variations in the PICP, PIIINP and ICTP levels between individual subjects, a follow-up study, including male and female patients, others than in the first part of the study, was conducted. Two other biochemical markers of bone metabolism, osteocalcin, reflecting osteoblastic activity, and tartrate-resistant acid phosphatase (TRAP), reflecting osteoclastic activity, were also analyzed. In females, all these parameters were lower than in males. In addition, the changes in females were more pronounced; in particular, PIIINP and TRAP were significantly increased in females during retinoid treatment (p < 0.05 and p < 0.01, respectively). Importantly, no increase was found in the synthesis of type I collagen during retinoid treatment, suggesting that the commonly used retinoid dosages do not stimulate the synthesis of type I collagen in vivo.

Acne Vulgaris↗

Effect of gynecological operations on the serum concentration of the aminoterminal propeptide of type III procollagen.

Serum concentration of PIIINP (aminoterminal propeptide of type III procollagen), an indicator of connective tissue metabolism, is often increased in advanced gynecological carcinoma and correlates with the tumor growth. Because the healing wound also affects collagen metabolism we measured the serum PIIINP concentration in 15 patients operated on for endometrial carcinoma and in 28 patients operated on for benign gynecological diseases. Serial serum samples were collected for 35-51 days after surgery. In endometrial carcinoma, serum PIIINP level was increased in 53% of the patients before the operation. Postoperatively, the mean PIIINP concentration increased further, remaining at a pathological level throughout the study and with a peak at one week after the operation. In relative terms an abdominal operation for benign disease increased the serum PIIINP concentration as much as in endometrial carcinoma, but the mean level remained within the reference interval. After vaginal operation the increase in PIIINP concentration was not significant. The initially increased PIIINP concentration in endometrial carcinoma is probably caused by the effects of the malignancy on collagen metabolism. Because the relative response of PIIINP to abdominal operation was similar in both groups, the PIIINP response to surgical trauma in patients with malignant disease seems to depend only on the extent of the operation. In this group the transient increase in serum PIIINP concentration does not prevent the use of PIIINP as a tumor marker, since the follow-up examinations for malignancy do not start earlier than two months after operation.

Adenocarcinoma↗

Biochemical markers of bone metabolism.

In this article we review the biochemical basis for markers of bone metabolism and comment on their bone specificity and representativeness for bone tissue. Major developments have recently taken place particularly with respect to markers of bone collagen metabolism; accordingly, they are in the focus of this review. We also attempt to relate the various collagenous and non-collagenous markers to each other and to the phases of the osteoblast phenotype.

Acid Phosphatase↗

Concurrent p53 expression in bronchial dysplasias and squamous cell lung carcinomas.

We analyzed the p53 protein immunohistochemically in bronchial dysplasias or squamous cell carcinomas in situ and in squamous cell lung carcinomas occurring in the same patients. The polyclonal antibody used (CM-1) is directed against the wild-type p53 protein, but also recognizes the mutated p53 in formalin-fixed and paraffin-embedded sections. To study the integrity of basement membranes (BMs) and the possible invasion of the dysplastic epithelium, immunostainings for the BM proteins laminin and type IV collagen were used. Nine of the 17 dysplasias showed p53 protein expression (53%); it was significantly more often seen in severe dysplasias and carcinomas in situ than in mild or moderate dysplasias (P = 0.04). The p53 antigenicity was generally located in the basal part of the epithelium. The BMs beneath mildly dysplastic epithelia were continuous. In contrast, those under moderately or severely dysplastic epithelia showed occasional disruptions. p53 protein expression was also found in dysplastic epithelium above a continuous BM suggesting an ominous process before signs of invasion. Twelve of the 17 squamous cell carcinomas showed p53 protein expression (71%). There was a significant concurrent p53 expression in bronchial dysplasias and their related squamous cell carcinomas (P = 0.009), so that all nine cases of p53 positive bronchial dysplasia also showed p53 positivity in the associated squamous cell carcinomas. These findings indicate that p53 protein expression is possible in premalignant bronchial lesions, and suggests that the p53 expression could, at least in some cases, be an early event in the development of a squamous cell carcinoma of the lung.

Aged↗

Radioimmunoassay for the pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen: a new serum marker of bone collagen degradation.

We developed a radioimmunoassay (RIA) for the carboxy-terminal telopeptides of type I collagen (ICTP), cross-linked with the helical domain of another type I collagen molecule, after isolation from human femoral bone. The cross-linked peptide was liberated by digesting insoluble, denatured bone collagen either with bacterial collagenase or with trypsin, and purified by two successive reversed-phase separations on HPLC, with monitoring of pyridinoline-specific fluorescence. The purity of the peptide was verified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and its origin in the type I collagen fibers was determined by amino-terminal amino acid sequencing. Polyclonal antibodies and a separation reagent containing second antibody and polyethylene glycol are used in the RIA. An immunologically identical, somewhat larger antigen is present in human serum; its concentration increases in multiple myeloma and in rheumatoid arthritis. The ICTP antigen seems to be cleared from the circulation by the kidneys, because glomerular filtration rates that are two-thirds of normal or less are associated with increased circulating ICTP concentrations. The CVs of the method are between 3% and 8% for a wide range of concentrations. The analysis of 40 serum samples can be completed in 4 h.

Adult↗

Hyperglycemic glucose concentrations up-regulate the expression of type VI collagen in vitro. Relevance to alterations of peripheral nerves in diabetes mellitus.

Electron microscopy of peripheral nerves obtained from two diabetic patients revealed large deposits of microfibrils and the presence of Luse bodies in the vicinity of perineurial cells. Microfibrils were found to accumulate also in the sciatic nerves of diabetic BB rats; these microfibrillar deposits were shown to contain type VI collagen by immunoelectron microscopy. Connective tissue cells cultured from rat sciatic nerves were exposed to high glucose concentrations. High glucose concentrations up-regulated the mRNA steady-state levels of alpha 1(VI), alpha 2(VI), and alpha 3(VI) chains of type VI collagen and caused accumulation of type VI collagen-containing fibrils in the cultures. Immunostaining and in situ hybridizations demonstrated that perineurial cells, Schwann cells, and fibroblasts expressed type VI collagen at the mRNA and protein levels. The results suggest that the turnover and supramolecular assembly of type VI collagen are perturbed in diabetic nerves and that glucose per se increases the expression of type VI collagen in vitro.

Adolescent↗

Serum procollagen peptides and collagen type VI for the assessment of activity and degree of hepatic fibrosis in schistosomiasis and alcoholic liver disease.

Schistosomiasis, in contrast to alcoholic liver disease, leads to presinusoidal hepatic fibrosis, which determines the prognosis of the disease. Because conventional liver function tests and liver biopsy specimens provide little information about the dynamics of the fibrotic process, we measured the serum concentrations of procollagen type III N-propeptide and procollagen type I C-propeptide, believed to mainly reflect collagen synthesis, and procollagen type IV C-propeptide and collagen type VI, two presumptive markers of collagen degradation. Determinations were performed in 15 healthy control subjects, 69 patients with various stages of infection with Schistosoma mansoni/Schistosoma haematobium (28 with an early active infection and no organ involvement, 27 with hepatosplenic involvement and 14 with complications of portal hypertension) and 16 patients with alcoholic cirrhosis. In addition, liver biopsy specimens were obtained from 30 schistosomal patients (18 with hepatosplenic involvement and 12 with complications of portal hypertension for histopathological grading and collagen histochemistry. Procollagen type III N-propeptide was significantly elevated in the three patient groups with schistosomiasis when compared with controls (p less than 0.01). Also, patients with higher histological grading showed significantly higher procollagen type III N-propeptide values (p less than 0.05). In alcoholic patients, procollagen type III N-propeptide was even higher and increased parallel to the severity of the disease, determined by using a combined clinical and laboratory index. Procollagen type I C-propeptide was only elevated in early infection (p less than 0.05) and steadily decreased with disease progression.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Diurnal variation in serum markers of type I collagen synthesis and degradation in healthy premenopausal women.

There are several indications that the functions of human osteoblasts and osteoclasts have circadian rhythms with peak activities occurring at night. It is not known, however, whether the principal function of these cells, namely synthesis and degradation of the organic matrix of bone, of which about 90% is type I collagen, also has a circadian rhythm. This was therefore investigated for both the formation of type I collagen and the degradation of type I collagen in bone using two newly developed serum markers: the serum concentration of the carboxy-terminal propeptide of type I procollagen (PICP) as a marker of formation and the serum concentration of the carboxy-terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP) as a marker of degradation. PICP and ICTP were measured by RIA in samples taken every 3 h over a 24 h period in 12 healthy premenopausal women (age 32 +/- 5 years, mean +/- SD). Both PICP (p = 0.003) and ICTP (p = 0.00003) showed a significant circadian rhythm, with about 20% higher values at night than in the afternoon. We conclude that serum markers of both the formation of new type I collagen and the degradation of old type I collagen in bone exhibit a clear circadian rhythm, with increased activity of both osteoblasts and osteoclasts at night. The etiology of this circadian rhythm is still unknown.

Adult↗

Laminin and its neurite outgrowth-promoting domain in the brain in Alzheimer's disease and Down's syndrome patients.

Immunocytochemistry, radioimmunoassay, immunoblotting, Northern analysis, and polymerase chain reaction (PCR) technique were applied to investigate the distribution of laminin and its neurite outgrowth domain in brains of neuropathologically verified cases of Alzheimer's disease and Down's syndrome. New antibodies against a neurite outgrowth domain of laminin were characterized and were used in localization of this peptide antigen in the human brain. Laminin was found as large punctate deposits in all plaques in the affected brains. Laminin synthesis was increased as assessed by RNA blotting and immunoblotting, and glial cells were heavily immunoreactive with antibodies for a neurite outgrowth-promoting peptide antigen of the B2 chain of laminin. This peptide antigen not only was produced by glial cells but also was deposited in the brain tissue. As this peptide antigen promotes neurite outgrowth at low concentrations, and is specifically neurotoxic at high concentrations, it may play a synergistic role with other molecules in inducing the sprouting and neurodegeneration occurring in brains of patients with either Alzheimer's disease or Down's syndrome.

Adult↗

Assessment of bone formation by biochemical markers in metabolic bone disease: separation between osteoblastic activity at the cell and tissue level.

In this study , serum levels of classical serum markers of bone formation [carboxyterminal propeptide of procollagen type I (S-PICP), bone Gla protein (S-BGP)], and total alkaline phosphatase (S-AP)) were related to the calcium kinetic index of whole skeletal mineralization rate (m) by regression analysis in a variety of metabolic bone diseases. For each disease, the regression coefficient (r) as well as the fraction: standard error of estimate/mean dependent variable (SEE/Y) were determined. In a group of 19 normals, only the regression of S-PICP on m reached significance (r = 0.53, P < 0.02, SEE/Y = 0.44), whereas regressions of S-AP and S-BGP on m were nonsignificant. In a pooled material of high- and low-turnover bone diseases without mineralization defects or spinal fracture [myxedema, thyrotoxicosis, and primary hyperparathyroidism (n = 48)], a highly significant positive regression of S-PICP on m was demonstrable (r = 0.50, SEE/Y = 0.63, P < 0.001). The regression coefficients obtained for S-BGP and S-AP were 0.74 (P < 0.001, SEE/Y = 0.41) and 0.42 (P < 0.01, SEE/Y = 0.55), respectively. When analyzing individual diseases in this group, significant differences among the three markers were detectable. In a group of 52 osteoporotics, S-PICP correlated significantly to m (r = 0.49, P < 0.001, SEE/Y = 0.50). Corresponding r-values for S-BGP and S-AP were 0.21 (NS) and 0.48 (P < 0.001, SEE/Y = 0.61), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Effect of insulin on serum amino-terminal propeptide of type III procollagen in non-insulin-dependent diabetes mellitus.

The effect of insulin on the serum levels of the amino-terminal propeptide of type III procollagen (PIIINP) was investigated in patients with non-insulin-dependent diabetes mellitus, whose disease was unsatisfactorily controlled by oral drugs. Before insulin therapy the PIIINP values of the patients (3.2 +/- 1.3 micrograms/l, n = 38) varied within the range of healthy subjects (3.1 +/- 0.6 micrograms/l, n = 50, NS). Insulin therapy (6-20 IU at bedtime plus the oral drugs) improved the glycemic control and increased the serum PIIINP during a 4 week (3.1 +/- 0.9 to 3.8 +/- 1.1 micrograms/l, P less than 0.01, n = 8) and an 8 week period (3.2 +/- 1.3 to 3.8 +/- 1.6 micrograms/l, P less than 0.001, n = 22). The values were still elevated after 6 months on insulin (3.5 +/- 1.5 to 4.0 +/- 1.7 micrograms/l, P less than 0.01, n = 12). Placebo-insulin did not alter the concentration of PIIINP (3.1 +/- 0.6 to 2.8 +/- 0.6 micrograms/l, NS, n = 8) whereas the glycemic control improved and body weight decreased. The PIIINP values correlated with fasting insulin before (r = 0.403, P less than 0.05, n = 30) and after the therapy (r = 0.452, P less than 0.001, n = 60). Insulin therapy, while correcting the hormone deficiency and restoring glucose and protein metabolism, seems to activate the synthesis of type III procollagen in patients with NIDDM. This may promote the atherosclerotic process.

Adult↗

Purification of porcine aminoterminal propeptide of type III procollagen from lymph and use for lymphatic clearance studies in pigs.

To investigate the lymphatic transport of the aminoterminal propeptide of type III procollagen (PIIINP) we established a thoracic duct-venous shunt in 6 pigs. Porcine PIIINP was purified, characterised, and compared with human PIIINP to ensure the suitability of the radioimmunoassay of human PIIINP for measurements in pigs. SDS-PAGE and radioimmunoinhibition assays show human and porcine PIIINP to be similar, thus indicating that the assay of human PIIINP is also reliable for determinations on pig serum and lymph. Intact PIIINP, as identified by gel filtration, accounted for 60% and 40% of the total PIIINP immunoreactivity in lymph and serum, respectively. The higher amount of total immunoreactivity and proportion of intact PIIINP in lymph compared with serum support the hypothesis that intact PIIINP is transported from peripheral tissue into the circulation by lymph. Two days after the shunt was established, the lymph was collected quantitatively hour-by-hour for 24 h. The flow was higher during the light periods than in the dark (p less than 0.01). The PIIINP concentration varied inversely with the flow, being higher in the dark hours (p less than 0.03). However, the total collected amount of PIIINP in lymph did not differ during the light and dark periods. Serum PIIINP remained unchanged over the 24 h. The lymphatic clearance of total PIIINP immunoreactive components was 6.2 ml serum/min and the lymphatic clearance of intact PIIINP was 9.1 ml serum/min, equal to 7 and 10 times the plasma volume/24 h, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Serum concentration of the cross-linked carboxyterminal telopeptide of type I collagen (ICTP) is a useful prognostic indicator in multiple myeloma.

Type I collagen is the main collagen type found in mineralised bone. Specific immunoassays for PICP (carboxyterminal propeptide of type I procollagen) and ICTP (cross-linked carboxyterminal telopeptide region of type I collagen) allow simultaneous assessment of the synthesis and degradation of type I collagen in serum samples, respectively. Our aim was to find out whether these metabolites of type I collagen are useful markers for following bone turnover and evaluating treatment response in multiple myeloma, which is a good model disease of excessive osteolysis. Fifteen consecutive patients were studied before and throughout their treatment. Samples for serum PICP and ICTP were collected before starting each treatment course of melphalan and prednisolon. Response to treatment was evaluated by following the changes in M protein and bone roentgenograms. The disease was progressing in four and regressive in 11 patients, but in four of these a recurrence occurred. In nonresponders the ICTP concentration was permanently elevated despite treatment. In responders both increased or normal levels of ICTP were initially observed, but they returned to or remained in the reference interval during treatment. The ICTP concentration increased upon recurring disease. There was a strong correlation between the extent of bone lesions and ICTP. There was no correlation between ICTP and PICP, the latter mainly remaining within the reference range, a finding that suggests no change in bone formation. ICTP was a significant predictor for survival in this patient group (P less than 0.05). We conclude that ICTP is a specific and sensitive marker for bone resorption. Simultaneous use of serum ICTP and PICP offers an additional and easy means to follow bone turnover and evaluate the response to therapy in multiple myeloma.

Biomarkers, Tumor↗

Type III collagen metabolism in soft tissue sarcomas.

Sera of 85 patients with benign soft tissue lesions or sarcomas of soft tissues were investigated for a collagen metabolite, the aminoterminal propeptide of type III procollagen (PIIINP). Patients were divided into three groups: benign soft tissue lesions (n = 39), localised (n = 29) and metastatic (n = 18) soft tissue sarcomas (STS). Values of PIIINP above the reference range were found in 15%, 28% and 50% of the respective groups. The difference in the concentration of PIIINP was statistically significant between the benign lesions and the localised sarcomas; P = 0.05, and between the benign lesions and the metastatic sarcomas; P less than 0.001. In localised sarcomas there was a correlation between PIIINP and bone-involvement (r = 0.61, P = 0.002) and in metastatic disease between PIIINP and liver metastases (r = 0.77, P less than 0.001). In localised sarcomas the overall survival for patients with a value of PIIINP above the reference range was significantly poorer (P = 0.03) than for patients with values within the reference range, even after stratification for the histological malignancy grade of the tumours (P = 0.04).

Collagen↗