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S Pitkänen

Publications and source records attributed to S Pitkänen.

14 recordsLinked to original sources
PubMed2004

A novel tumour necrosis factor receptor mutation in a Finnish family with periodic fever syndrome.

OBJECTIVE: To report a novel mutation of the TNF receptor type 1 gene (TNFRSF1A) in a Finnish patient and her mother, both suffering from periodic fever. METHODS: Soluble TNFRSF1A in serum was measured by enzyme-linked immunoabsorbancy, and induced TNFRSF1A shedding from monocyte cell surfaces was determined using fluorescence-activated cell sorter. Mutation detection was performed using PCR amplification and sequencing of the ten exons of TNFRSF1A. RESULTS: Low levels of soluble TNFRSF1A were detected in both patients between attacks. Sequencing revealed a missense mutation in exon 3 in the second extracellular domain of TNFRSF1A, resulting in a substitution of cysteine with arginine at residue 73 (C73R), confirming the diagnosis of TNF receptor-associated periodic syndrome (TRAPS). We were unable to demonstrate a distinct TNFRSF1A shedding defect. CONCLUSION: In patients of Nordic descent, affected by dominantly inherited recurrent fever, TRAPS is a diagnosis worthy of attention. All TNFRSF1A mutations hitherto described in the Nordic countries have been different.

Adult↗
PubMed2003

Association between serum oncofetal antigens CA 19-9 and CA 125 and clinical status in patients with cystic fibrosis.

UNLABELLED: In cystic fibrosis (CF), mucus plugging in the airways and in the gastrointestinal tract leads to severe morbidity and mortality. The mucin-associated antigens CA 19-9 and CA 125 are markers of gastrointestinal malignancy, and CA 19-9 has also been reported in association with pulmonary function in CF. AIM: To test whether these antigens might serve as markers for the severity of pulmonary and gastrointestinal disease in CF. METHODS: In 99 patients, aged 1 to 48 y, serum levels of CA 19-9 and CA 125 were measured by RIA and ELISA and related to clinical data. RESULTS: Patients with severe mutations had significantly increased serum levels of CA 125, indicating an association with a more severe CF phenotype. This was further supported by the association with lung function, chronic pulmonary colonization of Pseudomonas aeruginosa and pancreatic insufficiency. CA 19-9 was also shown to be associated with lung function and Ps. aeruginosa colonization. No gastrointestinal malignancy was found in our patients despite very high values of CA 19-9 in some patients. During a 5-y follow-up, the very high serum levels of CA 19-9 decreased along with improved general condition of the patients. CONCLUSION: Increased serum levels of CA 125 in CF patients were associated with severe cystic fibrosis transmembrane conductance regulator mutations and a severe phenotype. Both antigens were associated with pseudomonas colonization and lung function and CA 125 also with pancreatic insufficiency. The estimates of CA 19-9 are hampered by the influence of the Lewis histo-blood group system on the synthesis of CA 19-9.

Adolescent↗
PubMed2000

Mitochondrial dysfunction in congenital nephrotic syndrome.

The molecular mechanisms maintaining the kidney glomerular filtration barrier remain poorly understood. Recent evidence suggests that mitochondrial dysfunction is a characteristic feature of kidney glomeruli in congenital nephrotic syndrome of the Finnish type (CNF). Here we searched for detailed functional evidence of mitochondrial lesion in CNF kidneys. We used histochemical and immunohistochemical methods, quantitative measurement of mitochondrial DNA, and superoxide production to characterize the mitochondrial function. The results unequivocally show down-regulation of mitochondria-encoded respiratory chain components, whereas the respective nuclearly encoded subunits were close to normal. These results give detailed evidence of distinct mitochondrial dysfunction and of the resulting abnormal production of reactive oxygen species in CNF and suggest a critical role for mitochondria in maintaining the glomerular permeability barrier.

DNA, Mitochondrial↗
PubMed2000

Serum tumor marker CA 125 is an early and sensitive indicator of veno-occlusive disease in children undergoing bone marrow transplantation.

Veno-occlusive disease (VOD) is a potentially lethal complication of patients undergoing bone marrow transplantation (BMT). The diagnosis of VOD is currently based on clinical signs and unspecific laboratory findings. CA 125 is an oncofetal antigen used as a tumor marker in various malignancies, especially in those originating from the female reproductive tract or gastrointestinal organs, whereas serum CA 125 levels are not increased in hematological malignancies. Several pathophysiological alterations occurring in VOD may lead to elevations in serum CA 125 levels. Therefore, we explored the behavior of this marker as a diagnostic tool in VOD. Twenty-nine pediatric transplant patients were studied. Eight patients (28%) developed clinical VOD, and a significant increase in serum CA 125 was noted in all of them. During the 7 days preceding the diagnosis of VOD, an increase of at least 57% in serum CA 125 from the pre-BMT value was observed in 6 (86%) of 7 of the evaluable patients with VOD. In contrast, a similar increase was noted in only 6 of the 21 non-VOD patients during the post-BMT period of 30 days. Accordingly, the sensitivity and specificity of serum CA 125 for predicting or detecting VOD were 86% and 71%, respectively. The serum levels of CA 125 were not affected by the presence of Graft-versus-Host Disease (GvHD) or a septic infection. In conclusion, serum CA 125 is of value as an early marker of VOD in children undergoing BMT.

Adolescent↗
PubMed1999

Generation of reactive oxygen species by human mesothelioma cells.

Malignant mesothelioma cells contain elevated levels of manganese superoxide dismutase (MnSOD) and are highly resistant to oxidants compared to non-malignant mesothelial cells. Since the level of cellular free radicals may be important for cell survival, we hypothesized that the increase of MnSOD in the mitochondria of mesothelioma cells may alter the free radical levels of these organelles. First, MnSOD activity was compared to the activities of two constitutive mitochondrial enzymes; MnSOD activity was 20 times higher in the mesothelioma cells than in the mesothelial cells, whereas the activities of citrate synthase and cytochrome c oxidase did not differ significantly in the two cell lines. This indicates that the activity of MnSOD per mitochondrion was increased in the mesothelioma cells. Superoxide production was assayed in the isolated mitochondria of these cells using lucigenin chemiluminescence. Mitochondrial superoxide levels were significantly lower (72%) in the mesothelioma cells compared to the mesothelial cells. Oxidant production in intact cells, assayed by fluorimetry using 2',7'-dichlorodihydrofluorescein as a fluorescent probe, did not differ significantly between these cells. We conclude that mitochondrial superoxide levels are lower in mesothelioma cells compared to nonmalignant mesothelial cells, and that this difference may be explained by higher MnSOD activity in the mitochondria of these cells. Oxidant production was not different in these cells, which may be due to the previously observed increase in H2O2-scavenging mechanisms of mesothelioma cells.

Amitrole↗
PubMed1999

Serum type III procollagen in children with type I hereditary tyrosinemia.

BACKGROUND: Type I hereditary tyrosinemia leads to hepatic dysfunction and fibrosis and is associated with a high risk of hepatic malignancy. Serum N-terminal propeptide of type III procollagen is a sensitive marker of organ fibrosis of diverse origins. The current study was conducted to determine whether analysis of serum levels of type III procollagen in hereditary tyrosinemia would be useful in the follow-up of the progressive liver disease and eventually in detecting hepatic malignancy. METHODS: Serum N-terminal propeptide of type III procollagen was sequentially studied in 10 children with type I hereditary tyrosinemia. RESULTS: At diagnosis of type I hereditary tyrosinemia, serum N-terminal propeptide of type III procollagen ranged from 0.6 to 2.9 multiples of age-related median. During follow-up, serum N-terminal propeptide of type III procollagen decreased, yet remained elevated 0.2 to 2.6 years after diagnosis. Children with the acute type of the disease tended to have higher serum N-terminal propeptide of type III procollagen than did those with the chronic type. Porphyria crises were associated with elevated serum type III procollagen. The one patient receiving 2-(2-nitro-4-trifluoromethyl-benzoyl)-1,3-cyclohexanedione (NTBC) did not differ from the other ones in serum type III procollagen levels. Serum N-terminal propeptide of type III procollagen did not increase with developing hepatocellular carcinoma. CONCLUSIONS: Serum N-terminal propeptide of type III procollagen may be useful in monitoring the hepatopathy in type I hereditary tyrosinemia but is not useful in detecting malignant transformation in the liver.

Adolescent↗
PubMed1997

Excessive formation of hydroxyl radicals and aldehydic lipid peroxidation products in cultured skin fibroblasts from patients with complex I deficiency.

Previous studies suggest oxygen free radicals' involvement in the etiology of cardiomyopathy with cataracts. To investigate the role of free radicals in the pathogenesis of the cardiomyopathy with cataracts and complex I deficiency, fibroblasts from patients were assessed for hydroxyl radical formation and aldehydic lipid peroxidation products with and without redox active agents that increase free radicals. The rate of hydroxyl radical formation in patient cells was increased over 2-10-fold under basal conditions, and up to 20-fold after menadione or doxorubicin treatment compared with normal cells. We also found an overproduction of aldehydes in patient cells both under basal conditions and after treatment. Both hydroxyl radicals and toxic aldehydes such as hexanal, 4-hydroxynon-2-enal, and malondialdehyde were elevated in cells from patients with three types of complex I deficiency. In contrast, acyloins, the less toxic conjugated products of pyruvate and saturated aldehydes, were lower in the patient cells. Our data provide direct evidence for the first time that complex I deficiency is associated with excessive production of hydroxyl radicals and lipid peroxidation. The resultant damage may contribute to the early onset of cardiomyopathy and cataracts and death in early infancy in affected patients with this disease.

Aldehydes↗
PubMed1996

Assignment of the PSST subunit gene of human mitochondrial complex I to chromosome 19p13.

The cDNA for the PSST subunit of human mitochondrial nicotinamide adenine dinucleotide (NADH): ubiquinone oxidoreductase [complex I; NADH dehydrogenase (ubiquinone), Fe-S (20 kDa); EC 1.6.5.3] was generated by polymerase chain reaction (PCR) amplification of human cDNA. The sequence of the mature protein deduced from the cDNA codes for a protein that is closely related to the bovine protein (93% homology). Nine conservative substitutions are found in the mature protein, mainly in the N and C terminal regions. The mature human protein is missing four amino acids (PAAL) close to the N terminus that are present in the bovine protein. The N terminus of the mature protein is preceded by a presequence of 38 amino acids that, although quite different from its bovine counterpart (52% homology), has properties that are characteristic of a mitochondrial import sequence. Southern hybridization analysis predicts an estimated gene size of 3.8 kb. Northern hybridization analysis of mRNA from fibroblasts of complex I-deficient patients revealed no size or transcript level abnormalities. The cDNA of the PSST protein was used to investigate tissue-specific expression and to localize the gene for this subunit to chromosome 19p13.

Animals↗
PubMed1996

Diagnosis of complex I deficiency in patients with lactic acidemia using skin fibroblast cultures.

The requirement for a rapid and easy method of preparing mitochondrial fractions from cultured skin fibroblasts led us to compare the results obtained from such a preparation with the more traditional methods of cellular fractionation. Values for NADH-cytochrome c reductase (rotenone sensitive) were compared for a series of three controls and nine patients with complex I (NADH-coenzyme Q reductase deficiency). Values obtained for deficient cell lines varied from 19 to 64% of the control values for the long mitochondrial preparation method and from 34 to 70% of control for the rapid preparation. Mean values were statistically significantly different from the lowest control cell line (P < 0.01) in all cases. The specific activity on the basis of activity per milligram of mitochondrial protein and of activity per unit of citrate synthase activity was lower in the rapid preparation of mitochondria by some 41%, indicating a lesser degree of mitochondrial purification. However, the overall result showed that this type of rapid preparation, which uses four 9-cm petri dishes of cultured cells, can be used to diagnose mitochondrial complex I deficiency. This method will find general use in the measurement of either mitochondrial enzymes of low specific activity or mitochondrial enzymes whose measurement is made difficult by contaminating nonmitochondrial enzymes.

Cells, Cultured↗
PubMed1996

NADH-coenzyme Q reductase (complex I) deficiency: heterogeneity in phenotype and biochemical findings.

Twelve patient cell lines with biochemically proven complex I deficiency were compared for clinical presentation and outcome, together with their sensitivity to galactose and menadione toxicity. Each patient had elevated lactate to pyruvate ratios demonstrable in fibroblast cultures. Each patient also had decreased rotenone-sensitive NADH-cytochrome c reductase (complexes I and III) with normal succinate cytochrome c reductase (complexes II and III) and cytochrome oxidase (complex IV) activity in cultured skin fibroblasts, indicating a deficient NADH-coenzyme Q reductase (complex I) activity. The patients fell into five categories: severe neonatal lactic acidosis; Leigh disease; cardiomyopathy and cataracts; hepatopathy and tubulopathy; and mild symptoms with lactic acidaemia. Cell lines from 4 out of the 12 patients were susceptible to both galactose and menadione toxicity and 3 of these also displayed low levels of ATP synthesis in digitonin-permeabilized skin fibroblasts from a number of substrates. This study highlights the heterogeneity of complex I deficiency at the clinical and biochemical level.

Acidosis, Lactic↗
PubMed1995

Tumor markers CA 125 and CA 19-9 in cord blood and during infancy: developmental changes and use in pediatric germ cell tumors.

Tumor markers CA 125 and CA 19-9 are elevated in a variety of malignancies in adult patients, but only little is known of their biology during gestation or infancy. We have addressed the developmental pattern of these carbohydrate antigens in pediatric patients by measuring their serum levels in 133 cord blood samples from the second through third trimester of gestation and in 39 infants aged less than 1.5 y. The serum concentrations of both markers revealed developmental changes, the levels being higher at earlier gestation (wk 24 through 37) than at term or during infancy. The clinical value of the markers was evaluated by monitoring 26 children with germ cell tumors; 14 benign and 2 immature teratomas, and 11 malignant germ cell tumors. Patients with immature sacrococcygeal teratomas showed constant and prolonged elevations of serum CA 125 and CA 19-9. In contrast, all but two children with mature teratomas had normal marker levels; these two patients with abnormally high serum CA 125 and CA 19-9 values for the first 4 postoperative weeks had a benign ovarian and ventricular teratoma, respectively. Of the 11 children with malignant germ cell tumors, serum CA 125 or CA 19-9 concentration was elevated in four patients at diagnosis and declined to normal within 2 wk after institution of therapy. Malignant recurrence in two patients was not associated with a reelevation of the CA 125 level. Taken together, our results demonstrate a developmentally regulated pattern of serum CA 125 and CA 19-9. The carbohydrate markers were usually inferior to alpha-fetoprotein in monitoring of germ cell tumors, but may be a useful adjunct in the follow-up of immature teratomas.

CA-125 Antigen↗
PubMed1994

Serum levels of oncofetal markers CA 125, CA 19-9, and alpha-fetoprotein in children with hereditary tyrosinemia type I.

Hereditary tyrosinemia type I (HTT-I) is an inherited metabolic disorder with severe liver disease and a high risk for hepatic malignancy. Patients with HTT-I are monitored with repeated analyses of serum amino acids, urine succinylacetone, and serum alpha-fetoprotein (AFP). Oncofetal markers CA 125 and CA 19-9 are elevated in serum of patients with various gastrointestinal diseases and malignancy. To study the biology of oncofetal antigens in tyrosinemia and to assess the possible usefulness of these markers in HTT-I, we studied serum concentrations of CA 125 (n = 160) and CA 19-9 (n = 188), together with AFP (n = 337), in serial samples from 10 patients. At early stages of the disease, most children with an acute type of disease had a remarkably elevated serum CA 125 concentration (153-1560 IU/L) that normalized gradually after the institution of therapy. Serum CA 125 levels may thus reflect acute metabolic imbalance in fulminant HTT-I. The patients with a chronic type of disease showed CA 125 levels within the normal range at diagnosis that slowly increased as the liver condition worsened. These concentrations, however, never reached values seen in acute HTT-I. Serum concentration CA 19-9 in HTT-I was mostly normal. Serum AFP levels fluctuated in all patients and positively correlated with tests for metabolic state and biliary function. A distinct increase in the serum AFP level was recorded in association with the detection of massive hepatocellular carcinoma and also preceded metabolic imbalance leading to porphyria crises.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Metabolism, Inborn Errors↗