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Dive into the research topics where Ilkka Sipilä is active.

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Featured researches published by Ilkka Sipilä.


The New England Journal of Medicine | 1990

Clinical Variation of Autoimmune Polyendocrinopathy–Candidiasis–Ectodermal Dystrophy (APECED) in a Series of 68 Patients

Pekka Ahonen; Sinikka Myllärniemi; Ilkka Sipilä; Jaakko Perheentupa

To define the clinical picture and course of the autosomal recessive disease called autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), we report data from our 10-month to 31-year follow-up of 68 patients from 54 families, now 10 months to 53 years of age. The clinical manifestations varied greatly and included from one to eight disease components, 63 percent of the patients having three to five of them. The initial manifestation was oral candidiasis in 41 patients (60 percent), intestinal malabsorption in 6 (9 percent), and keratopathy in 2 (3 percent). All the patients had candidiasis at some time. The earliest endocrine component appeared at 19 months to 35 years of age. Hypoparathyroidism was present in 54 patients (79 percent), adrenocortical failure in 49 (72 percent), and gonadal failure in 15 (60 percent) of the female patients greater than or equal to 13 years of age and 4 (14 percent) of the male patients greater than or equal to 16 years of age. There were multiple endocrine deficiencies in half the patients. From 4 to 29 percent of the patients had periodic malabsorption, gastric parietal-cell atrophy, hepatitis, alopecia, vitiligo, or a combination of these conditions. Dental-enamel hypoplasia and keratopathy were also frequent but were not attributable to hypoparathyroidism. In the patients whose initial manifestation (other than candidiasis) was adrenal failure, the other components developed less often than in the remaining patients. We conclude that the clinical spectrum in patients with APECED is broad. The majority of patients have three to five manifestations, some of which may not appear until the fifth decade. Therefore, all patients need lifelong follow-up for the detection of new components of the disease.


The Lancet | 2001

A specific aromatase inhibitor and potential increase in adult height in boys with delayed puberty: a randomised controlled trial

Sanna Wickman; Ilkka Sipilä; Carina Ankarberg-Lindgren; Ensio Norjavaara; Leo Dunkel

BACKGROUND The role of oestrogens in the closure of growth plates in both sexes is unequivocal. We postulated that inhibition of oestrogen synthesis in boys with delayed puberty would delay maturation of the growth plates and ultimately result in increased adult height. METHODS We did a randomised, double-blind, placebo-controlled study in which we treated boys with constitutional delay of puberty with testosterone and placebo, or testosterone and letrozole. Boys who decided to wait for the spontaneous progression of puberty without medical intervention composed the untreated group. FINDINGS Letrozole effectively inhibited oestrogen synthesis and delayed bone maturation. Progression of bone maturation was slower in the letrozole group than in the placebo group. In 18 months, bone age had advanced 1.1 (SD 0.8) years in the untreated group and 1.7 (0.9) years in the group treated with testosterone and placebo, but only 0.9 (0.6) years in the letrozole group (p=0.03 between the treatment groups). Predicted adult height did not change significantly in the untreated group and in the placebo group, whereas in the group treated with letrozole the increase was 5.1 (3.7) cm (p=0.004). INTERPRETATIONS Our findings suggest that if oestrogen action is inhibited in growing adolescents, adult height will increase. This finding provides a rationale for studies that aim to delay bone maturation in several growth disorders.


The New England Journal of Medicine | 1981

Supplementary Creatine as a Treatment for Gyrate Atrophy of the Choroid and Retina

Ilkka Sipilä; Juhani Rapola; Olli Simell; Antti Vannas

Gyrate atrophy of the choroid and retina is a disease characterized by progressive constriction of visual fields, a 10-fold to 20-fold elevation in plasma ornithine, and depressed activity of L-ornithine:2 oxoacid aminotransferase. Morphologically conspicuous but clinically unimportant atrophy of Type II muscle fibers progresses concomitantly with the eye disease. A pathogenic component of the disease may be deficient formation of creatine, caused by hyperornithinemia, which leads to a shortage of cellular phosphocreatine energy stores. To test the therapeutic value of replenishing the postulated deficiency of creatine, we supplemented the diet of seven patients with 1.5 g of creatine daily. During one year of this treatment the diameters of Type II muscle fibers increased from 34.1 +/- 7.1 to 49.9 +/- 7.0 micron (mean +/- S.D.) (P less than 0.001). There was no significant increase in the diameters of Type I fibers. The visual-field tests showed no further constriction during the therapy. Fundus photography revealed slow impairment at an age otherwise associated with rapid progression of the disease. These promising preliminary results need further evaluation with long-term follow-up studies.


The Journal of Clinical Endocrinology and Metabolism | 2013

Growth Hormone Research Society Workshop Summary: Consensus Guidelines for Recombinant Human Growth Hormone Therapy in Prader-Willi Syndrome

Cheri Deal; Michèle Tony; Charlotte Hoybye; David B. Allen; Maïth́e Tauber; Jens Sandahl Christiansen; Geoffrey Ambler; Renaldo N. Battista; Véronique Beauloye; Glenn Berall; Beverly M. K. Biller; Merlin G. Butler; Suzanne B Cassidy; Kazuo Chihara; Pinchas Cohen; Maria E. Craig; Stense Farholt; Mireille Goetghebeur; Anthony P. Goldstone; Tiziana Greggi; Graziano Grugni; Anita Hokken-Koelega; Gudmundur Johannsson; Keegan Johnson; Alex R. Kemper; John J. Kopchick; Saul Malozowski; Jennifer L. Miller; Harriette R. Mogul; Françoise Muscatelli

Context: Recombinant human GH (rhGH) therapy in Prader-Willi syndrome (PWS) has been used by the medical community and advocated by parental support groups since its approval in the United States in 2000 and in Europe in 2001. Its use in PWS represents a unique therapeutic challenge that includes treating individuals with cognitive disability, varied therapeutic goals that are not focused exclusively on increased height, and concerns about potential life-threatening adverse events. Objective: The aim of the study was to formulate recommendations for the use of rhGH in children and adult patients with PWS. Evidence: We performed a systematic review of the clinical evidence in the pediatric population, including randomized controlled trials, comparative observational studies, and long-term studies (>3.5 y). Adult studies included randomized controlled trials of rhGH treatment for ≥ 6 months and uncontrolled trials. Safety data were obtained from case reports, clinical trials, and pharmaceutical registries. Methodology: Forty-three international experts and stakeholders followed clinical practice guideline development recommendations outlined by the AGREE Collaboration (www.agreetrust.org). Evidence was synthesized and graded using a comprehensive multicriteria methodology (EVIDEM) (http://bit.ly.PWGHIN). Conclusions: Following a multidisciplinary evaluation, preferably by experts, rhGH treatment should be considered for patients with genetically confirmed PWS in conjunction with dietary, environmental, and lifestyle interventions. Cognitive impairment should not be a barrier to treatment, and informed consent/assent should include benefit/risk information. Exclusion criteria should include severe obesity, uncontrolled diabetes mellitus, untreated severe obstructive sleep apnea, active cancer, or psychosis. Clinical outcome priorities should vary depending upon age and the presence of physical, mental, and social disability, and treatment should be continued for as long as demonstrated benefits outweigh the risks.


Acta Paediatrica | 2007

Growth hormone treatment of short children born small-for-gestational-age: the Nordic Multicentre Trial

M Boguszewski; Kerstin Albertsson-Wikland; S Aronsson; J Gustafsson; Lars Hagenäs; Ulf Westgren; Otto Westphal; M Lipsanen-Nyman; Ilkka Sipilä; P Gellert; J Müller; B Madsen

The aims of this study were to evaluate the efficacy and safety of different doses of growth hormone (GH) treatment in prepubertal short children born small‐for‐gestational‐age (SGA). Forty‐eight children born SGA from Sweden, Finland, Denmark and Norway were randomly allocated to three groups: a control group of 12 children received no treatment for 2 y, one group was treated with GH at 0.1 IU/kg/d (n= 16), and one group was treated with GH at 0.2 IU/kg/d (n= 20). In total 42 children completed 2 y of follow‐up, and 24 children from the treated groups completed 3 y of treatment. Their mean (SD) age at the start of the study was 4.69 (1.61) y and their mean (SD) height was ‐3.16 (0.70) standard deviation scores (SDS). The children remained prepubertal during the course of the study. No catch‐up growth was observed in the untreated group, but a clear dose‐dependent growth response was found in the treated children. After the third year of treatment, the group receiving the higher dose of GH, achieved their target height. The major determinants of the growth response were the dose of GH used, the age at the start of treatment (the younger the child, the better the growth response) and the family‐corrected individual height deficit (the higher the deficit, the better the growth response). Concentration of insulin‐like growth factor‐I (IGF‐I) and IGF‐binding protein‐3 increased during treatment. An increase in insulin levels was found without negative effects on fasting glucose levels or glycosylated haemoglobin levels. GH treatment was well tolerated. In conclusion, short prepubertal children born SGA show a dose‐dependent growth response to GH therapy, and their target height SDS can be achieved within 3 y of treatment given GH at 0.2 IU/kg/d. However, the long‐term benefit of different regimens of GH treatment in children born SGA remains to be established.


Acta Paediatrica | 1990

Recombinant Human Growth Hormone Treatment in Short Children with Chronic Renal Disease, before Transplantation or with Functioning Renal Transplants: an Interim Report on Five European Studies

G Johansson; A Sietnieks; F Janssens; Willem Proesmans; M Vanderschueren-Lodeweyckx; C. Holmberg; Ilkka Sipilä; M Broyer; R Rappaport; K Albertssonwikland; U Berg; U Jodal; Lesley Rees; Spa Rigden; Ma Preece

Growth retardation is common in children with chronic renal disease. Final adult height is often reduced, even in children with a functioning renal transplant. The five European studies considered here aim to investigate the efficacy and safety of recombinant human growth hormone therapy (rhGH) in two groups of short children with chronic renal disease. The first group comprises 29 prepubertal children with preterminal chronic renal failure (i.e. before renal transplantation), and the second group comprises 39 prepubertal and pubertal children with functioning renal transplants. The median bone age retardation in the groups at the start of treatment was between 2.2 and 3.7 years; this did not change during the first year of treatment. This interim report concentrates on patients who have been treated for at least 1 year (i.e. 22 children from the first group, and 28 children from the transplant group (15 prepubertal and 13 pubertal children). The median height velocity increased from 4.8 cm/year to 10.0 cm/year in the first group (the chronic renal failure group), from 2.6 cm/year to 6.2 cm/year in prepubertal children with renal transplants and from 3.8 cm/year to 6.7 cm/year in pubertal children with renal transplants. The corresponding changes in height velocity SDS were from ‐1.3 to 5.1 for the chronic renal failure group and ‐2.8 to 2.3 for the prepubertal children with renal transplants. Renal function declined in the chronic renal failure group but this decline corresponded to expected progression of the disease. Some of the children with renal transplants showed a decreased renal function, which in most cases was explained by non‐compliance or chronic rejection.


Pediatric Research | 1986

Waste nitrogen excretion via amino acid acylation: benzoate and phenylacetate in lysinuric protein intolerance.

Olli Simell; Ilkka Sipilä; Jukka Rajantie; David Valle; Saul W. Brusilow

ABSTRACT: Benzoate and phenylacetate improve prognosis in inherited urea cycle enzyme deficiencies by increasing waste nitrogen excretion as amino acid acylation products. We studied metabolic changes caused by these substances and their pharmacokinetics in a biochemically different urea cycle disorder, lysinuric protein intolerance (LPI), under strictly standardized induction of hyperammonemia. Five patients with LPI received an intravenous infusion of 6.6 mmol/kg L-alanine alone and separately with 2.0 mmol/kg of benzoate or phenylacetate in 90 min. Blood for ammonia, serum urea and creatinine, plasma benzoate, hippurate, phenylacetate, phenylacetylglutamine, and amino acids was obtained at 0, 120, 180, and 270 min. Urine was collected in four consecutive 6-h periods. Alanine caused hyperammonemia: maximum increase 107, 28-411 µM (geometric mean, 95% confidence interval); ammonia increments were nearly identical after alanine + benzoate (60, 17-213 µM) and alanine + phenylacetate (79, 13-467 µM) (NS). Mean plasma benzoate was 6.0 mM when extrapolated to the end of alanine + benzoate infusions; phenylacetate was 4.9 mM at the end of alanine + phenylacetate. Transient toxicity (dizziness, nausea, vomiting) occurred in four patients at the end of combined infusions, and we suggest upper therapeutic plasma concentrations of 4.5 mM for benzoate and 3.5 mM for phenylacetate. Benzoate and phenylacetate then decreased following first-order kinetics with t1/2s of 273 and 254 min, respectively. Maximal plasma hippurate (0.24, 0.14-0.40 mM) was lower than maximal phenylacetylglutamine (0.48, 0.22-1.06 mM, p=0.008). Orotic acid excretion was 5.62, 1.84-17.14 µmol/kg per h after alanine, but only 1.07, 0.04-25.62 µmol/kg per h after alanine + benzoate (p<0.151) and 2.74,0.01-16.25 µmol/ kg per h after alanine + phenylacetate (p<0.016). Urea excretions were in the same range after all loads. Urinary hippurate nitrogen after alanine + benzoate and phenylacetylglutamine, nitrogen after alanine + phenylacetate accounted for an average of 12 and 22 of that in urea in the first 6 h. Of the benzoate and phenylacetate given, 65 and 51% were excreted in 24 h as hippurate and phenylacetyl-glutamine, respectively; less than 3.5% appeared unchanged in urine.


Ophthalmology | 1985

Gyrate Atrophy of the Choroid and Retina: A Five-year Follow-up of C'reatine Supplementation

Kaarina Vannas-Sulonen; Ilkka Sipilä; Antti Vannas; Olli Simell; Juhani Rapola

Gyrate atrophy of the choroid and retina (GA) is an autosomal recessive chorioretinal degeneration with a 10-20-fold elevation of plasma ornithine due to deficient activity of ornithine aminotransferase. Type II fibres of the skeletal muscle are atrophic and contain tubular aggregates in electron microscopy. Deficient creatine and creatine phosphate formation have been postulated to be involved in the pathogenesis of GA. The five-year follow-up results of oral creatine supplementation in 13 patients are presented. Visual function tests and fundus photographs showed progression of GA during the treatment. The velocity of the progression varied considerably between individuals. Generally, the progression was rapid in the young patients and slow in the more advanced stages. Abnormalities in the skeletal muscle decreased or disappeared rapidly. They reappeared in the few patients who discontinued the medication. The difference in the therapeutic effect on the skeletal muscle and eye is discussed.


Neurology | 1979

Gyrate atrophy of the choroid and retina with hyperornithinemia: Tubular aggregates and type 2 fiber atrophy in muscle

Ilkka Sipilä; Olli Simell; Juhani Rapola; Kimmo Sainio; Leena Tuuteri

We studied 21 patients with gyrate atrophy of the choroid and retina and hyperornithinemia. Although the patients were not weak, type 2 muscle fibers were almost universally atrophic and had tubular aggregates. Gyrate atrophy is the first disease in which females are shown to have tubular aggregates; the sexes were affected equally. In gyrate atrophy the number of type 2 fibers decreases with age. The muscle and eye changes are probably related to abnormal creatine synthesis, caused, in gyrate atrophy, by the increased body pool of ornithine; muscle abnormalities may also be present in other tapetoretinal dystrophies.


Biochimica et Biophysica Acta | 1980

Inhibition of arginine-glycine amidinotransferase by ornithine. A possible mechanism for the muscular and chorioretinal atrophies in gyrate atrophy of the choroid and retina with hyperornithinemia

Ilkka Sipilä

The inhibitory effect of ornithine on L-arginine:glycine amidinotransferase (EC 2.1.4.1) was studied in crude rat kidney homogenates. The enzyme activity was linear with time up to 45 min and with protein up to 200 microgram. The apparent Km and V of amidinotransferase were 9.21 mM and 1.53 mu mol/g protein per min, respectively. The enzyme was competitively inhibited by ornithine, with a Ki of 0.253 mM. Kidney arginase was inhibited only slightly and non-competitively. The inhibition of amidinotransferase by ornithine may thus be important in creatine biosynthesis. In gyrate atrophy of the choroid and retina with hyperornithinemia, a human autosomal recessive disease caused by decreased ornithine aminotransferase activity, plasma ornithine concentrations are elevated 10-20-fold (0.65-1.35 mM during fasting). In consequence endogenous creatine production probably is severely decreased because of inhibition of the rate-limiting transamidination step by ornithine. The deficiency of creatine and further of readily available energy in the form of phosphocreatine is suggested to be involved in the pathogenesis of the choroidal, retinal and type II muscle fiver atrophies in gyrate atrophy.

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Olli Simell

Turku University Hospital

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David Valle

Howard Hughes Medical Institute

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Gary Steel

Johns Hopkins University School of Medicine

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