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S Vobecky

Publications and source records attributed to S Vobecky.

9 recordsLinked to original sources

[Growth and pubertal development following pediatric heart transplantation].

STUDY AIM: Prospective study of growth and pubertal development following pediatric heart transplantation in 25 children. PATIENTS AND METHOD: Twenty-five children underwent orthotopic cardiac transplantation at Ste-Justine Hospital from July 1984 to August 1996. Systematic evaluation of anthropometric parameters (weight, height, bone age), hormonal profile (LH, FSH, testosterone, oestradiol, DHEAS), and pubertal development according to Marshall and Tanner were done yearly. RESULTS: Six patients had severe growth retardation at transplantation and only one patient was obese. All patients showed normal height increment following cardiac transplantation. Only 3 patients will not reach genetic target height. The 6 children suffering from congenital cardiomyopathy and showing severe growth delay before surgery did not show any significant catch up growth. Significant weight gain was observed during the first post-operative year (113 +/- 27% ideal body weight p = 0.0002) with evolution towards normal values at 2 years (100 +/- 18%). Thirteen patients were in the prepubertal stage at the time of transplant. Since then, one girl had her menarche at 11 years of age and 3 boys started their pubertal onset at 12 years old. The elevation of blood gonadotrophins during pubertal development correlated with progression of secondary sexual characteristics in both sexes. CONCLUSION: This pediatric population showed normal growth and normal onset and progression of puberty following cardiac transplantation. However, no catch-up growth was observed. The most important factor influencing attainment of maximal growth potential following heart transplantation was the degree of staturoponderal growth retardation at the time of surgery.

Adolescent↗

Growth and pubertal development following pediatric heart transplantation: a 15-year experience at Ste-Justine Hospital.

BACKGROUND: Thirty-one children and adolescents have undergone allograft heart transplantation at Ste-Justine Hospital from July 1984 to August 1996. Twenty-five patients were followed prospectively more than 3 years to document their growth and pubertal development. METHODS: Parameters surveyed were clinical (height, weight, pubertal staging, and bone age) and biochemical (luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, estradiol, dehydroepiandrosterone sulphate (DHEAS), IGF-1, and fasting insulin). RESULTS: At surgery, there were 18 boys and 7 girls aged 11 months to 17 years (median 13 years); 14 had congenital heart defects (CHDs) and 11 had a cardiomyopathy (CM). Immunosuppressive therapy included cyclosporine, azathioprine, and prednisone. Eighteen patients were still growing (15 boys, 3 girls): 8 had a retarded bone age and 6 with CHD had severe growth failure. Following surgery, most patients maintained their height within one sodium dodecyl sulfate (SDS) score of that initially observed. Patients reaching their target heights do so mainly in the lower range. Three patients not reaching target height had a CHD. Weight was greatest 1 year postoperatively (113 +/- 27% ideal body weight) with normalization at 2 years (100 +/- 18%). Of the 13 prepubertal patients, menarche occurred at age 12 in 1 girl, while 3 boys began puberty at age 12 years. In both sexes, serum levels of gonadotropins and IGF-1 increased during puberty, moderate hyperinsulinism was observed, and DHEAS levels decreased. CONCLUSIONS: Our results indicate that children and adolescents grow normally following cardiac transplantation and that they attain their target height despite a lack of catch-up growth. They gain weight significantly in the first postoperative year with normalization of their weight at 2 years. Furthermore, the clinical and biochemical indices of puberty are overall within the norms. However, the severity of growth delay at the time of transplantation inherent to the cardiac pathology has a major impact on adult height.

Adolescent↗

Succinyl CoA: 3-oxoacid CoA transferase (SCOT): human cDNA cloning, human chromosomal mapping to 5p13, and mutation detection in a SCOT-deficient patient.

Succinyl CoA: 3-oxoacid CoA transferase (SCOT; E.C.2.8.3.5) mediates the rate-determining step of ketolysis in extrahepatic tissues, the esterification of acetoacetate to CoA for use in energy production. Hereditary SCOT deficiency in humans causes episodes of severe ketoacidosis. We obtained human-heart SCOT cDNA clones spanning the entire 1,560-nt coding sequence. Sequence alignment of the human SCOT peptides with other known CoA transferases revealed several conserved regions of potential functional importance. A single approximately 3.2-kb SCOT mRNA is present in human tissues (heart > leukocytes >> fibroblasts), but no signal is detectable in the human hepatoma cell line HepG2. We mapped the human SCOT locus (OXCT) to the cytogenetic band 5p13 by in situ hybridization. From fibroblasts of a patient with hereditary SCOT deficiency, we amplified and cloned cDNA fragments containing the entire SCOT coding sequence. We found a homozygous C-to-G transversion at nt 848, which changes the Ser 283 codon to a stop codon. This mutation (S283X) is incompatible with normal enzyme function and represents the first documentation of a pathogenic mutation in SCOT deficiency.

Amino Acid Sequence↗

[Pubertal development after pediatric heart transplantation].

Twenty-one children and adolescents underwent orthotopic cardiac transplantation at the Hôpital Sainte-Justine between July 1984 and June 1993. Of those patients, 16 (4 girls and 12 boys) who survived more than one year after the procedure were followed prospectively for documentation of onset and progression of puberty. The immunosuppressive therapy included cyclosporine, azathioprine and prednisone. Subjects were evaluated at 6 month intervals for the study of: pubertal development according to staging by the method of Marshall and Tanner and hormonal profile (FSH, LH, testosterone, DHEAS). Despite a stagnation of pubertal signs before surgery, puberty carried on and progressed normally postoperatively. The urinary levels of gonadotropins rose to adequate levels for age. Testosterone levels in boys were related to the progression of secondary sexual characteristics. Levels of DHEAS were drastically reduced, most likely because of the supraphysiological doses of oral glucocorticoids. Our results indicate that after pediatric heart transplantation, puberty progresses normally at adolescence.

Adolescent↗

[Pulmonary valve replacement in children].

From February 1988 to October 1994, 15 pulmonary valve replacements (PVR) have been performed at St-Justine Hospital in children with a mean age of 145.7 months. Ten children previously had a correction of tetralogy of Fallot; two had absent pulmonary valve syndrome; one had been operated on for pulmonary atresia with intact ventricular septum, one other had a correction for a ventricular septal defect with pulmonary artery banding; the last patient developed degeneration of a pulmonary bioprosthesis. The time between the primary repair and the PVR ranged from 61 to 221 months. Fourteen bioprosthesis and one aortic homograft were implanted. All patients had antiplatelet treatment. There was one operative death due to a fatal anaphylactic reaction and one late death occurred unrelated to valvular surgery. At follow-up from 1 to 187 months (mean, 40.7 months) all patients were in New York Heart Association Class 1. No hemorrhagic nor thromboembolic complication have been observed and no reoperation for bioprosthesis failure was necessary. Nevertheless in subsequent echocardiographic studies, two patients with the smallest bioprosthesis (21 mm) have developed pulmonary gradients of 80 and 85 mmHg, 65 and 80 months following PVR. While our results with PVR in children have been satisfactory, this operation should be performed only in symptomatic patients with severe pulmonary regurgitation because of progressive deterioration of the available bioprosthesis.

Adolescent↗

[Aortic valve replacement in children].

From January 1970 to January 1993, 47 aortic valve replacements have been performed in children aged 166.8 +/- 50 months. The valvular pathology was congenital in 39 patients and associated cardiac anomalies were present in 31 cases. 30 children had a previous surgical procedure on the aortic outflow. Seven bioprosthesis and 40 mechanical valves have been implanted. At the time of surgery, an additional major cardiac correction has been performed on 17 occasions (Konno, Bentall, Fontan, correction of truncus arteriosus etc.). While no death occurred in the group subjected only to aortic valve replacement, 7 of the 17 patients where a major cardiac procedure was added died. During a mean follow-up of 61.2 +/- 59.1 months, 3 late deaths occurred, 2 of them non related to valvular surgery. Three reoperations have been performed, in two instances for replacing a degenerated bioprosthesis. One thromboembolic event occurred as well as one temporary episode of haemolytic anaemia. No haemorrhagic complication has been observed. While the results of isolated aortic valve replacement in children are excellent, the risk for hospital death is increased substantially when a major cardiovascular procedure is added to valve replacement, and because of rapid deterioration, the heterografts are now contra-indicated in children.

Adolescent↗

Hindgut dysgenesis as a cause of constipation with delayed colonic transit.

In a patient complaining of constipation since birth, delayed transit time in the ascending colon was related to a congenital malformation of the hindgut, different from Hirschsprung's disease. This was associated with absence of the left lobe of the liver. There was no propagating electrical muscular activity in the distal bowel.

Adult↗

Ischemic fecal incontinence and rectal angina.

In 36 patients who consulted for fecal incontinence or rectal pain, or both, there was grossly visible scarring of the rectum and biopsy revealed mucosal atrophy and fibrosis. A steal from the hemorrhoidal arteries to the iliac vessels was demonstrated in 3 subjects. Maximum tolerable volumes within a rectal balloon were smaller than in control subjects, both in men (192 vs. 273 ml) and in women (142 vs. 217 ml) (p less than 0.01). The rectoanal inhibitory reflex was abnormal in all but 1 patient. Specific abnormalities were a decreased amplitude or a prolonged duration of the reflex. It was totally absent in 2 patients. This study is compatible with the hypothesis that chronic ischemia of the rectum may cause fecal incontinence or rectal pain.

Adult↗