Search PubMed⌕ Search

Biomedical subjects

J Risteli

Publications and source records attributed to J Risteli.

At least 19 recordsLinked to original sources

Apoptosis and apoptosis-related proteins in human endometrium.

Apoptosis has been shown to be an important regulator of endometrium function. To study the regulation of apoptosis in the endometrium during the normal menstrual cycle, the expression of the apoptosis related proteins Bcl-2 and Bax and their correlation to serum estradiol and progesterone, as well as to a replication-related antigen Ki-67 were analyzed. Nine uterine tissue samples and thirty-nine endometrial biopsy specimens were studied. Apoptosis was studied quantitatively by Southern blot analysis of internucleosomal cleavage of genomic DNA, and qualitatively by using in situ 3'-end labeling of fragmented DNA, and Bcl-2, Bax and Ki-67 were detected and quantified immunohistochemically. Apoptotic cells were mostly detected in the glandular epithelium of late secretory and menstruating endometrium. Immunostaining of Ki-67 was detected predominantly in proliferative endometrium. The expression of Bcl-2 was high in proliferative endometrium and decreased in the secretory phase, being very low or absent in the mid- and late secretory and menstruatory phases. Similarly, Bax expression also decreased, but was still present throughout the secretory phase. In human endometrium, apoptosis occurs predominantly in the late secretory and menstrual phases, and is related to alterations in the expression of Bcl-2 and Bax. A decrease in the Bcl-2/Bax ratio in the early secretory phase precedes DNA fragmentation and may predispose the cells to apoptosis.

Apoptosis↗

Immunochemical characterization of assay for carboxyterminal telopeptide of human type I collagen: loss of antigenicity by treatment with cathepsin K.

The assay for the cross-linked carboxyterminal telopeptide of type I collagen (ICTP) has been shown to reflect increased type I collagen degradation in such pathological conditions as bone metastases and rheumatoid arthritis, but to be rather insensitive to the changes in physiological bone collagen turnover (e.g., induced by estrogen or bisphosphonate treatment). To determine the reasons for this discrepancy we localized the antigenic determinant recognized by the ICTP assay and studied the effects of two major osteoclastic proteinases, cathepsin K (EC 3.4.22.38) and matrix metalloproteinase-9 (MMP-9; gelatinase B; EC 3.4.24.35), on immunoreactivity. The antigenic determinant was shown to reside within the hydrophobic phenylalanine-rich regions of the carboxyterminal telopeptides of the two alpha1 chains of human type I collagen, situated between the triple helical domain and the lysine-derived trivalent cross-link. This conclusion was based on differences between the amino acid sequences and cross reactivities of the corresponding human and bovine antigens before and after proteolytic treatments with chymotrypsin. A trivalent cross-link is necessary for providing such a structure, because the divalently cross-linked and monomeric natural and synthetic peptides from the same region, but containing only one phenylalanine-rich sequence, showed poor immunoreaction. Recombinant human cathepsin K cleaved the trivalently cross-linked ICTP structure at two sites between the phenylalanine-rich region and the cross-link, destroying the reactivity with ICTP antibodies. On the contrary, the treatment of isolated ICTP by the matrix metalloproteinases MMP-9 (gelatinase B), MMP-1 (collagenase 1), or MMP-13 (collagenase 3) had no effect on the immunoreaction. Our results indicate that the increased circulating concentrations of ICTP found in several clinical situations are most likely produced by matrix metalloproteinases, whereas cathepsin K-mediated, osteoclastic bone resorption destroys ICTP antigenicity.

Amino Acid Sequence↗

Modulation of skin collagen metabolism by irradiation: collagen synthesis is increased in irradiated human skin.

Radiation-induced fibrosis is a common side-effect of cancer treatment. The pathophysiological events leading to fibrosis are not known in detail. We analysed the effect of therapeutic irradiation on human skin collagen synthesis, skin thickness, gelatinases and their inhibitors. Twenty randomly chosen women who had been treated for breast cancer with surgery and radiation therapy participated in the study. In each patient, the irradiated skin area was compared with a corresponding non-treated skin area. Suction blister fluid (SBF) and serum samples were analysed for the aminoterminal propeptides of type I and type III procollagens (PINP and PIIINP), tissue inhibitors of matrix metalloproteinases (MMPs) 1 and 2 (TIMP-1 and TIMP-2) and MMP-9 and MMP-2/TIMP-2 complex. Skin biopsies were analysed for PINP and immunohistochemical staining was used for PIIINP. In irradiated skin, PINP, PIIINP, TIMP-1 and MMP-2/TIMP-2 complex levels in SBF and the number of PINP-positive fibroblasts in tissue sections were significantly higher in comparison with non-treated skin. The levels of TIMP-2 in irradiated and non-irradiated skin were similar. MMP-9 could not be detected in SBF with the assay used. The serum levels of MMP-9 were higher in the treated subjects than the reference values. The serum values of PINP, PIIINP, TIMP-1, TIMP-2 and MMP-2/TIMP-2 complex were not significantly affected. These results indicate increased local collagen synthesis and accumulation of connective tissue in irradiated skin. The marked upregulation of collagen synthesis as a result of irradiation offers a possibility to treat this complication with compounds such as topical steroids which downregulate collagen synthesis.

Adult↗

The course of selected bone resorption marker concentrations in response to short-term hypocalcemia experimentally induced with disodium EDTA infusions in dairy cows.

The collagen metabolites hydroxyproline (HYP), deoxypyridinoline (DPD), and the carboxyterminal telopeptide of type I collagen (ICTP) are suitable markers for bone resorption in humans and several animal species. The purpose of this study was to describe the course of bone resorption markers during short-term hypocalcemia induced with disodium ethylenediaminetetraacetic acid (Na2EDTA) and to investigate whether bone resorption is increased in dairy cows under these conditions. EDTA infusions have been used as a model for periparturient paresis in dairy cows and to estimate the calcium mobilization rate from body reserves in ruminants. In this study, hypocalcemia was induced by means of a 5% Na2EDTA infusion (0.55 mg/kg/min Na2EDTA for 5 h = total dose of 100.6 g). Two experiments were conducted: (1) Six 4-11 years-old Brown Swiss cows were infused intravenously with EDTA for 5 h. Blood and urine samples were taken repeatedly from 1 day before until 10 days after infusion. (2) Towards the end of the lactation, the experiment was repeated with the same animals after a 14-day-period of feeding a low calcium diet (26 g/animal per day). The EDTA-infusion induced hypocalcemia and hypophosphatemia. The HYP-, DPD- and ICTP-concentration remained mainly unaffected during both infusions. Only DPD showed an increase during infusion and HYP an increase 2 days after the infusion. In conclusion, the EDTA infusion had little effect on the concentrations of the measured bone markers, which may be due to the fact that the serum calcium pool was refilled by increased absorption of Ca via the gastrointestinal tract. From these results, it can be concluded that bone resorption was not influenced by EDTA infusion.

Amino Acids↗

Increased amount of type III pN-collagen in human abdominal aortic aneurysms: evidence for impaired type III collagen fibrillogenesis.

PURPOSE: This study aimed to characterize the distribution of structural domains of type I and III collagens in the wall of abdominal aortic aneurysms (AAAs), by the use of undilated atherosclerotic aortas (aortoiliac occlusive disease [AOD]) and healthy abdominal aortas as controls. METHODS: Immunohistochemical staining was applied with antibodies for the aminoterminal propeptides of type I (PINP) and type III (PIIINP) procollagens, which represent newly synthesized type I and III pN-collagens. In addition, an antibody against the aminoterminal telopeptide of type III collagen (IIINTP) was used as a means of detecting maturely cross-linked type III collagen fibrils. RESULTS: The newly synthesized type III procollagen detected by means of PIIINP staining was concentrated in the media in aneurysmal aortas, whereas type I pN-collagen was localized in the intima in both AAAs and AODs. The healthy aortas showed no immunoreactivity for either PIIINP or PINP. The cross-linked type III collagen, detected by means of IIINTP staining, stained transmurally in all study groups, but appeared more abundant in the media in AAAs. CONCLUSION: Our results strongly suggest that the metabolism of type III collagen is enhanced in AAAs. Intensive type III pN-collagen staining was present mainly in the media layer in AAAs, suggesting a role of type III collagen in aneurysm formation, whereas type I pN-collagen was present in the intima in both AAAs and AODs, suggesting that type I collagen synthesis is a fibroproliferative response related to the atherosclerotic process. The increased type III pN-collagen in AAAs may result in impaired fibril formation and, thus, in decreased tensile strength of aneurysmal tissue.

Aged↗

Type I and III collagens in human colon cancer and diverticulosis.

BACKGROUND: Collagens are major proteins in the extracellular matrix, providing tissues with tensile strength. They are also important for cell adhesion and the invasion of malignant tumours. METHODS: Thirty-nine samples of human colon (24 diverticulosis, 6 malignant tumours, 9 controls) were collected during elective surgery. Immunoassays for different domains of type I and III collagens and procollagens were used in soluble tissue extracts and trypsin digests of tissue samples. RESULTS: The contents of cross-linked type I and III collagen telopeptides and total collagen were similar in diverticulosis and healthy tissue, whereas in malignant tissue maturely cross-linked type III collagen was scarce. Furthermore, some of the cross-linked type I telopeptide antigens were exceptionally small in size, indicating that the cross-linking of type I collagen in collagen fibres is impaired in cancer. The rate of type I collagen synthesis was clearly increased in malignancy, but not significantly in diverticulosis. However, type III collagen synthesis was increased in diverticulosis, but not in malignancy. CONCLUSIONS: In colon malignancy, the collagen cross-linking process was aberrant and the synthesis of type I collagen increased. In diverticulosis, the synthesis of type III collagen was increased, suggesting only moderately increased metabolic activity.

Adult↗

Prediction of disease progression in early rheumatoid arthritis by ICTP, RF and CRP. A comparative 3-year follow-up study.

OBJECTIVE: To test the predictive value of the cross-linked carboxyterminal telopeptide of type I collagen (ICTP; a marker of type I collagen degradation), rheumatoid factor (RF) and C-reactive protein (CRP) for disease progression in patients with early rheumatoid arthritis (RA) METHOD: We tested the value of baseline values of RF, CRP and ICTP for the prediction of radiological joint progression over 3 yr in 63 consecutive patients with early RA who were treated with the 'saw-tooth strategy'. RESULTS: Age- and sex-adjusted risks as odds ratios (95% confidence intervals) of elevated serum ICTP, RF positivity and increased CRP for progressive joint disease (defined as an increase of > 20 in Larsen's index on radiographs of the hands and feet) were 3.9 (1.3, 11.9), 3.9 (1.0, 15.5) and 2.6 (0.9, 7.5), respectively. Better prediction was achieved when the tests were used in combination, and where there was both elevated ICTP and positive RF the odds ratio was 9.1 (2.5, 32.9). This test combination showed good sensitivity and specificity (71 and 77%, respectively), with a positive predictive value of 65% and a likelihood ratio of 3.1. CONCLUSION: This kind of risk profile, in which the tests used reflect different aspects of the disease process, may be useful in early disease assessment to find patients who will need the most active drug therapy.

Adolescent↗

Decreased protein C activation is associated with abnormal collagen turnover in the intraalveolar space of patients with interstitial lung disease.

Activation of the coagulation system in the alveolar space plays an important role in the pathogenesis of interstitial lung disease (ILD) and pulmonary fibrosis. The protein C (PC) pathway is the main modulator of coagulation activation. This study evaluated whether dysfunction of the PC pathway is associated with increased collagen synthesis in the intraalveolar space of patients with ILD. This study comprised 22 patients with ILD; of these, five had idiopathic pulmonary fibrosis (IPF), nine had sarcoidosis-associated ILD, and eight had collagen vascular disease-associated ILD (CVD-ILD). Thrombin-antithrombin complex (TAT) was measured as a marker of coagulation activation. As markers of the PC pathway activity, the concentration of activated PC-PC inhibitor (APC-PCI) complex and the APC-PCI/PC ratio were measured and, as a marker of collagen synthesis, the concentration of aminoterminal propeptide of type III procollagen (PIIINP) was measured in bronchoalveolar lavage fluid (BALF) of ILD patients. TAT was significantly increased in BALF from ILD patients as compared to control subjects. The concentrations of PIIINP were significantly elevated in patients with ILD as compared to healthy subjects. In contrast, the concentration of APC-PCI and the values of APC-PCI/PC ratio were significantly decreased in BALF from patients with ILD. BALF concentration of PIIINP was significantly and inversely correlated with the concentration of APC-PCI and with the APC-PCI/PC ratio. These findings suggest that dysfunction of the protein C pathway may have important physiopathologic implications in the development of pulmonary fibrosis in ILD.

Biomarkers↗

Biochemical markers of bone formation and resorption around parturition and during lactation in dairy cows with high and low standard milk yields.

Substantial changes occur in skeletal metabolism during lactation. These dynamic changes are monitored with biochemical bone markers. The goal of the present study was to follow these changes in lactating cows and to investigate whether cows with a higher milk yield have a higher mobilization rate of calcium from bone. Hydroxyproline, deoxypyridinoline, pyridinoline, and the carboxyterminal telopeptide of type I collagen (ICTP) were chosen as markers for bone resorption, whereas osteocalcin was used as a bone formation marker. Urine and blood samples were collected from cows with a mean standard milk yield of 4900 and 6500 kg, respectively, 14 d before, and 14 d, 1 mo, 1.5 mo, and monthly after parturition. Urinary hydroxyproline, deoxypyridinoline, and pyridinoline concentrations increased with time, but no differences between the two groups were evident. Concentrations of 1,25-dihydroxy vitamin D and ICTP of the two groups showed an increase 14 d after parturition. Furthermore, using multivariate regression models with age and milk yield as covariates, ICTP concentrations were higher in the group with a higher milk yield. In contrast, osteocalcin concentrations decreased 14 d after parturition and returned to prepartum values 1 mo after parturition. The increase of ICTP concentrations in both groups indicates that bone was substantially resorbed. At the same time, probably less Ca was embedded in bone, as indicated by the decrease of the osteocalcin concentrations. In conclusion, cows showed increased bone resorption around parturition, and cows with higher milk yield mobilize calcium more actively from bone than cows with lower milk yield.

Animals↗

Characterization of type I collagen synthesis and maturation in uterine carcinosarcomas.

BACKGROUND: Epithelial malignancies often induce an enhanced expression of interstitial collagens in the fibroblasts within the tumor tissue and the surrounding non-neoplastic stroma. In uterine carcinosarcomas (malignant mixed müllerian tumors [MMMTs]) both the stroma and the epithelium are malignant. METHODS: In this investigation, both in situ hybridization and immunohistochemical staining were applied with two different antibodies that were capable of distinguishing between newly synthesized and mature, trivalently cross-linked Type I collagen to define Type I procollagen mRNA expression and the synthesis and maturation of the corresponding protein in MMMTs. RESULTS: In the better differentiated parts of these tumors, in which anticytokeratins stained only clearly carcinomatous cells, Type I procollagen mRNA expression was limited to stromal fibroblasts; mature Type I collagen bundles were abundant and regular. In poorly differentiated areas, in which anticytokeratins stained only a few individual cells, Type I procollagen mRNA was expressed peculiarly by three morphologically different cell types. In addition to benign mesenchymal cells, Type I procollagen mRNA was present in atypical epithelial and mesenchymal cells. In these tumors, the collagen bundles close to the malignant cells were comprised of newly synthesized Type I collagen, with only little evidence of the presence of mature, fully cross-linked collagen. CONCLUSIONS: These results strongly suggest that the undifferentiated cells of MMMTs are capable of producing their own stroma with irregularly arranged collagen bundles.

Aged↗

Type I collagen metabolites as tumor markers in patients with lung carcinoma.

BACKGROUND: Components of the extracellular matrix play a fundamental role in the process of tumor invasion. The objective of this study was to evaluate the value of Type I collagen metabolites as tumor markers in patients with lung carcinoma. METHODS: In this study, the serum concentrations of the cross-linked carboxyterminal telopeptide of Type I collagen (ICTP) and the aminoterminal propeptide of Type I collagen (PINP) were measured in 59 consecutive patients with lung carcinoma. The blood concentrations of neuron-specific enolase (NSE), carcinoembryogenic antigen (CEA), sialyl Le-1 antigen (SLX), squamous cell carcinoma antigen (SCC), and D-dimer were also evaluated. Data obtained on 18 age-matched healthy subjects and 12 age-matched patients with benign lung disease were available for comparison. RESULTS: The serum concentrations of PINP were significantly higher in patients with lung carcinoma than in age-matched controls. Prechemotherapy values of PINP and ICTP were significantly increased in patients who did not respond to chemotherapy compared with those who did respond. PINP and ICTP were significantly correlated with clinical stage, extent of bone metastasis, survival time, and D-dimer. PINP was also significantly correlated with tumor size. ICTP was significantly correlated with CEA, SLX, SCC, and NSE. PINP also tended to correlate with these tumor-associated glycoproteins. PINP had a better receiver operating characteristic curve than ICTP. The specificity of PINP (79%) for the diagnosis of bone metastasis was superior to that of ICTP (58%). CONCLUSIONS: The results of this study showed that, in addition to the important information that ICTP and PINP provide about the tumor cell-extracellular matrix interaction, they appear to be of great value as adjunct tools for the diagnosis of bone metastasis and as markers of the clinical response to therapy, clinical progression, and prognosis in lung carcinoma patients. However, more studies must be conducted to evaluate further the utility of these markers before their application in clinical practice.

Adult↗

Intraluminal fibromyxoid lesions in bronchiolitis obliterans organizing pneumonia are highly capillarized.

Bronchiolitis obliterans organizing pneumonia (BOOP) and usual interstitial pneumonia (UIP; ie, cryptogenic fibrosing alveolitis of mural type, CFA) are clinically and histologically distinguishable interstitial lung diseases. Both contain intraluminal lesions of newly formed fibromyxoid connective tissue. In BOOP, the fibromyxoid lesions are susceptible to complete reversal, but in UIP they are supposed to participate in the remodeling of the interstitium. Our hypothesis was that capillarization of the intraluminal fibromyxoid lesions is more frequent in BOOP compared with UIP. In this study, we stained diagnostic thoracoscopic or open lung biopsy specimens of patients with BOOP (n = 9) and UIP (n = 10) with antibodies against human laminin, von Willebrand factor, and CD34 to reveal the microvasculature of intraluminal fibromyxoid lesions. Our results show that in BOOP there is abundant capillarization in the newly formed intraluminal fibromyxoid lesions often reminiscent of granulation tissue. The mean number of capillaries per area unit (mm2) was 107 +/- SD 74 in samples stained for laminin, 103 +/- SD 46 for von Willebrand factor, and 63 +/- SD 36 for CD34. In marked contrast, in UIP, the corresponding accounts were significantly lower, being 14 +/- SD 15 for laminin (P < .003), 11 +/- SD 14 for von Willebrand factor (P < .001) and 6 +/- SD 6 for CD34 (P < .001). The intraobserver (P < .001) and interobserver correlations (P < .002) were highly significant, showing that our results are reproducible. We conclude that the content and nature of the newly formed intraluminal connective tissue, for example, in the form of vascular growth factors, are different in BOOP and in UIP, and this partly leads to the different clinical course of these diseases.

Adult↗

Annual serum PICP and ICTP and antler growth in female reindeer (Rangifer tarandus tarandus).

Annual cycle of type I collagen formation and degradation and antler growth was studied in six adult female reindeer, Rangifer tarandus tarandus. Blood samples were collected twice a week during 1 year. Antler length was measured weekly during the antler growth period. An assay for human PICP, the carboxyterminal propeptide of type I procollagen, was used as an indicator of type I collagen formation and an assay for bovine ICTP, the carboxyterminal telopeptide of type I collagen, as an indicator of type I collagen degradation. PICP was clearly increased during the antler growth period. Also ICTP was slightly elevated during antler growth, but the highest values were found in autumn and winter. Our statistical analysis revealed that changes in lagged values (from 3 to 6 weeks) of PICP could be linked to the subsequent changes in the growth rate of the antler, although the highest values of PICP were found during the final third of antler growth. ICTP had significant predictive power as well, but the connection with the growth rate seemed more immediate than that of PICP. In conclusion, antler collagen synthesis can be predicted by PICP, but also ICTP was related to the antler growth.

Animals↗

Carboxyterminal propeptide of type I procollagen in ELF: elevation in asbestosis, but not in pleural plaque disease.

Markers of collagen metabolism may possibly be used in the assessment of pulmonary involvement in asbestosis-related pulmonary diseases. In this study the levels of the carboxyterminal propeptide of type I procollagen (PICP) and the aminoterminal propeptide of type III procollagen (PIIINP) were evaluated in bronchoalveolar lavage fluid (BALF), epithelial lining fluid (ELF) and serum from patients with asbestos related pulmonary and pleural involvement. Forty-two consecutive patients with occupational exposure to asbestos fibres, who underwent bronchoscopy and bronchoalveolar lavage (BAL) at the time of the diagnosis were investigated. Five patients were diagnosed as having asbestosis, while 37 showed no parenchymal involvement. Of the latter group, 25 had pleural plaques, while 12 had no detectable changes in chest radiographs. The patients were followed-up for an average of 7 yrs. The PICP in BALF and ELF was detectable in all patients with asbestosis and in 8/37 subjects without parenchymal involvement. The levels of PICP in BALF and ELF were significantly higher in the asbestosis group compared to the patients without asbestosis (9.8+/-1.8 microg x L(-1) versus 0.6+/-1.3 microg x L(-1), p<0.001 and 488.9+/-208.8 microg x L(-1) versus 22.6+/-50.6 microg x L(-1), p<0.001, respectively). Only 1 patient with asbestosis and 3 patients without parenchymal involvement had detectable levels of PIIINP in BALF. The serum levels of PICP and PIIINP did not differ between the patients with asbestosis and those with exposure to asbestos fibres without asbestosis and were within the normal range. None of the 37 patients exposed to asbestos fibres without parenchymal involvement at the baseline developed asbestosis during the follow-up period of 7 yrs. In conclusion, the data show that the carboxyterminal propeptide of procollagen type I, but not the aminoterminal propeptide of type III procollagen is highly elevated in bronchoalveolar lavage fluid and epithelial lining fluid in patients with asbestosis, but not in those without parenchymal involvement. This suggests that the determination of carboxyterminal propeptide of procollagen type I in bronchoalveolar lavage fluid could be used as a marker of parenchymal involvement in patients exposed to asbestos fibres.

Asbestos↗

Postoperative systemic corticosteroid treatment and Molteno implant surgery: a randomized clinical trial.

PURPOSE: To determine whether it is possible to improve the surgical success of Molteno implantation by causing a general suppression of collagen synthesis with postoperative oral prednisolone. METHODS: Twenty-two patients requiring single stage, single-plate Molteno implantation were randomized into two study groups: the control group A and the systemic prednisolone treatment group B. Serum markers of collagen metabolism were monitored. RESULTS: A successful outcome at the end of the 6-month follow-up, defined as final IOP > or =6 mmHg and < or =22 mmHg with less or equal number of antiglaucoma medication as preoperatively and no additional surgery was achieved in 9 of 11 (82 %) patients of group A and in 5 of 10 (50 %) patients of group B (p= 0.18). There was a statistically significant decrease in serum markers of collagen synthesis in the group B but not in the group A. CONCLUSION: The serum markers indicated a systemic effect of oral prednisolone on collagen synthesis in group B but it did not improve the surgical outcome as compared to the controls.

Administration, Oral↗

Cross-linked telopeptides of type I and III collagens in malignant ovarian tumours in vivo.

Malignant tumours often induce a fibroproliferative response in the adjacent stroma, characterized by increased expression of type I and type III procollagens. In normal tissues, fibrillar collagens normally undergo extensive intermolecular cross-linking that provides tensile strength to the tissue. Here we set out to characterize collagen cross-linking in human ovarian carcinoma tissue in vivo. Biochemical and immunochemical methods were used for cross-linked telopeptides of type I and III collagens in samples of benign and malignant serous tumours. The locations and staining patterns of these proteins were visualized immunohistochemically. The contents of both total collagen and the cross-linked type I and type III collagens in the malignant samples were only about 20% of those in the benign tumours. The cross-linked telopeptide antigens derived from the collagens were smaller and more heterogeneous in size in the malignant than in the benign tumours, indicating a defective cross-linking process scarcely leading to the formation of mature cross-links in the collagen fibres in malignancy. Immunostaining revealed disorganized type I and type III collagen bundles in carcinomas. These findings suggest that the collagen cross-linking process is aberrant in malignant tumours, possibly resulting in increased susceptibility of tumour collagens for the proteolysis often associated with tumour invasion.

Collagen↗

The extracellular matrix in skin tumor development-a morphological study.

The development of cancer involves epithelial-stromal interactions. Alterations in the synthesis and deposition of type I and III collagens are related to the tumor morphology. Skin carcinogenesis in experimental animals provides a reliable model for the development of neoplasia. Ultraviolet (UV) irradiation is the main etiological factor for epidermal dysplasia and malignant tumors in man, but also for dermal degeneration. Non-neoplastic dermal changes and skin tumors induced by ultraviolet irradiation and 7,12-dimethylbenz(a)anthracene were investigated in various mouse strains with different susceptibilities to tumor formation. UVB irradiation resulted in an increased immunoreactivity of collagens in the dermis, in comparison with 7,12-dimethylbenz(a)anthracene. Increased synthesis and deposition of type I and III collagens were found in the stroma adjacent to benign alterations. In well-differentiated squamous cell carcinomas, a similar induction of collagen synthesis and deposition was observed. The destruction of fibrillary structures was more pronounced during the decrease of differentiation from moderately to poorly differentiated squamous cell carcinomas. Anaplastic carcinomas with spindle cell morphology displayed a delicate meshwork of reticular fibers and collagen III, and abnormal expression of mRNA for collagens in some malignant cells with epithelial characteristics. The underlying stroma reacts to the development of epithelial tumors in a reproducible way, which is related to the carcinogenic agent involved.

Animals↗

The value of synovial fluid analysis in the assessment of knee joint destruction in arthritis in a three year follow up study.

OBJECTIVES: To assess the predictive significance of synovial fluid (SF) analysis for progressive radiological knee joint destruction in arthritis. METHODS: Altogether 55 patients with arthritis and knee joint effusion were included in the study. The diagnosis was rheumatoid arthritis (RA) for 44 of them, chronic seronegative spondylarthropathy for seven and juvenile rheumatoid arthritis for four. The mean age of the patients was 51.8 (SD 14.9, range 19-82) years, and the mean duration of disease 10.9 (SD 9.2, range 0.5-37) years. In addition to the routine laboratory tests, different markers of collagen synthesis and breakdown in serum and SF were assessed. The radiological grade of the knee joint was assessed by Larsen's method at the baseline and after a three year follow up. RESULTS: During the follow up, Larsen's grade deteriorated in 22 (40%) patients. These patients had a significantly higher median level of cross linked carboxyterminal telopeptide of type I collagen (ICTP) in SF at entry than those who had a stable index (p = 0.035). Serum ICTP did not have any predictive value for a specific joint. The median levels of total SF leucocytes (p = 0.012) and the subgroup of polymorphonuclear leucocytes (p = 0.018) were higher in the patients with a stable Larsen's index. However, the relation of SF leucocyte level to radiological progression could not be confirmed in the RA group. CONCLUSION: It is concluded that SF analysis may help in the identification of patients with inflammatory arthritis who are at risk for progressive destruction in a particular joint. A high total SF leucocyte level is not necessarily associated with a poor prognosis. Instead, a high SF ICTP level seems to reflect accelerated bone degradation.

Adult↗