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Research Notes: PWS Abstracts - 2003[ 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 | 1999 | 1998 | 1997 | 1996 | 1995 | 1994 | 1993 | 1992 | 1991 | 1990 | 1980-1989 | 1979 and prior ] Growth Horm IGF Res. 2003 Dec. Prader-Willi syndrome (PWS) is a complex genetic disorder characterised by mild mental retardation and distinct physical, behavioural, and psychiatric features. One of the cardinal symptoms is excessive eating, which - if left untreated - leads to extreme obesity. In the present study we have examined circulating levels of peptides with documented association to hyperphagia in young adults with PWS. Since growth hormone (GH) is often used nowadays to correct GH insufficiency during childhood PWS, we also studied the impact of GH administration on the peptides. Seventeen adults, 9 men and 8 women, 17-32 years of age with a mean BMI of 35+/-3.2 kg/m(2) participated. All had clinical PWS (Holm's criteria). Genetic testing was performed in all patients and in 11 the diagnosis was confirmed. They were randomized to treatment with either placebo or GH (Genotropin, Pharmacia Corporation) for 6 months. Subsequently all received open label treatment to provide all subjects with 12 months active GH treatment. Doses were individually titrated. Weight, BMI, oxytocin (baseline only), leptin, Neuropeptide Y (NPY), and ghrelin were evaluated at baseline and after 6 and 12 months. At baseline plasma mean oxytocin was within and serum ghrelin just above the normal range (14.7+/-1.2 pmol/L and 0.87+/-0.12 microg/L, respectively). Serum leptin levels were high above and plasma NPY levels within the lower normal range (47.8+/-29.1 microg/L and 13+/-1 pmol/L, respectively). Results were independent of genotype. No changes in mean BMI, ghrelin, leptin or NPY were seen following GH treatment. Conclusion: Leptin levels were in general high reflecting obesity and as a consequence NPY levels were low. In simple obesity oxytocin levels are high, while ghrelin levels are suppressed. In view of the adiposity oxytocin circulated in abnormally low and ghrelin in abnormally high concentrations in our patients. GH treatment of PWS patients did not change ghrelin, leptin or NPY. We suggest that both oxytocin and ghrelin are involved in the pathogenesis of hyperphagia seen in PWS. Hum Mol Genet. 2003 Oct 15. Although uniparental disomy often results from the postzygotic rescue of a meiotic non-disjunction event, mosaicism is usually confined to the placenta. We describe a girl with Prader-Willi syndrome (PWS) who is mosaic for normal cells and cells with maternal uniparental disomy 15 [upd(15)mat] in blood and skin. Somatic mosaicism was confirmed by cloning and genotyping of skin fibroblasts. X inactivation studies indicated that upd occurred prior to X inactivation. RNA samples from the cloned cells were used in DNA microarray experiments to study the effect of upd(15)mat on the gene expression pattern of fibroblasts. Proof of principle was obtained by detecting several chromosome 15 genes known to be imprinted. We did not obtain any evidence for novel 15q genes showing imprinted expression in fibroblasts. Differentially expressed genes on other chromosomes are candidates for downstream genes regulated by an imprinted gene and may play a role in the pathogenesis of PWS. The finding of strongly reduced mRNA levels in upd(15)mat cells of the gene encoding secretogranin II (SCG2), which is a precursor of the dopamine releasing factor secretoneurin, raises the question whether hyperphagia in patients with PWS might be due to a defect in dopamine-modulated food reward circuits. Growth Horm IGF Res. 2003 Oct. Objective: Prader Willi syndrome (PWS) is a genetic disorder characterised by short stature, extreme obesity, body composition abnormalities and behavioural problems. Hypothalamic dysfunction with low growth hormone (GH) secretion and low levels of GH-related growth factors is common. However, the interpretation is difficult because of the concomitant obesity, which in itself has important effects on the GH-IGF-I-system. We therefore analysed free and total IGF-I, total IGF-II and their binding proteins in obese PWS adults before and during 12 months GH treatment. Seventeen adults, 9 men and 8 women, 17-32 years of age with a mean BMI of 35+/-2.3 kg/m(2) participated. All had clinical PWS. They were randomized to treatment with placebo or GH (Genotropin, Pharmacia) 0.8 IU (0.26 mg) for one month, and then 1.6 IU (0.53 mg) for 5 months. Subsequently GH doses were individually titrated to normal levels for age. Overnight fasting levels of free and total IGF-I, total IGF-II, GH-binding protein (GHBP) and IGF-binding proteins (IGFBP)-1, -2 and -3 were measured by RIA at baseline and after 6 and 12 months GH treatment. Mean levels+/-SEM of free IGF-I were 1.02+/-0.12 microg/L as compared to a reference value of 0.95+/-0.15 microg/L, while mean total IGF-I was 128+/-15 microg/L (212+/-14 microg/L) and total IGF-II was 704+/-45 microg/L (825+/-34 microg/L). Mean IGFBP-2 158+/-24 microg/L (764+/-72 microg/L) and GHBP 2.65 nmol/L (1.71+/-0.3 1nmol/L). IGFBP-1 and IGFBP-3 levels were normal. Both free and total IGF-I increased significantly during GH treatment, while IGF- and GH-binding proteins as well as total IGF-II remained unchanged. Conclusion: Low total IGF-I and, in relation to the obesity, low free IGF-I, low total IGF-II and non-suppressed IGFBP-1 are consistent with the concept that PWS patients have a partial GH deficiency, which can be corrected by GH replacement. J Pediatr. 2003 Sep. Objective: Infants with Prader-Willi syndrome (PWS) are hypotonic and underweight before the onset of childhood obesity. This study evaluates body composition in the PWS infant and its relationship to energy expenditure. Study design: Sixteen infants and toddlers with PWS (mean age, 12.4+/-6 months; eight female subjects) underwent analysis of body composition with dual-energy x-ray absorptiometry and deuterium dilution, and energy expenditure with both doubly labeled water and indirect calorimetry. Results: Percent body fat was significantly increased (male subjects, P<.001; female subjects, P<.001) and fat-free mass (FFM) was significantly decreased (male subjects, P<.001; female subjects, P=.04) in infants with PWS when compared with age-matched published data for normal infants. Meanwhile, total energy expenditure was significantly decreased (male subjects, P=.025; female subjects, P<.001) in infants with PWS when compared with published normative data. There was a normal relationship between FFM and total energy expenditure in infants with PWS. Conclusion: Compared with published data for infants without PWS, infants with PWS demonstrate increased percent body fat, decreased FFM, and decreased energy expenditure. Importantly, total energy expenditure per kilogram of FFM appears similar in infants with and without PWS. We conclude that lower energy expenditure in infants with PWS is caused by decreased FFM. J Intellect Disabil Res. 2003 Sep. BACKGROUND: Prader-Willi syndrome (PWS) is characterized by an increased risk for obsessive-compulsive disorder. This study investigated the nature of compulsive-like behaviours in the PWS. METHOD: Parents of 50 individuals with PWS (aged 5-18 years) and 50 typically developing 4-year-old children completed the Childhood Routines Inventory. This instrument measures compulsive-like behaviours in normative childhood. RESULTS: Many childhood compulsive behaviours are prevalent among older children and adolescents with PWS. Group differences were observed in that the PWS group, independent of age, gender and cognitive dysfunctions, exhibited more intense compulsive behaviours related to insistence on sameness in many daily activities and social contexts. Findings also revealed an age-independent low-prevalent pattern of PWS compulsivity, probably related to other features in the PWS symptomatology. CONCLUSIONS: Compulsions of childhood do not subside with age in adolescents with PWS. The findings indicate that the differentiation between delayed childhood rituals and pathological manifestations of compulsive features is complex in PWS populations. J Med Genet. 2003 Aug. BACKGROUND: Prader-Willi syndrome (PWS), the most common genetic cause of marked obesity, is caused by genomic imprinting and loss of expression of paternal genes in the 15q11-q13 region. There is a paucity of data examining simultaneous gene expression in this syndrome. METHODS: We generated cDNA microarrays representing 73 non-redundant genes/transcripts from the 15q11-q13 region, the majority within the PWS critical region and others distally on chromosome 15. We used our custom microarrays to compare gene expression from actively growing lymphoblastoid cell lines established from nine young adult males (six with PWS (three with deletion and three with UPD) and three controls). RESULTS: There was no evidence of expression of genes previously identified as paternally expressed in the PWS cell lines with either deletion or UPD. We detected no difference in expression of genes with known biallelic expression located outside the 15q11-q13 region in all cell lines studied. There was no difference in expression levels of biallelically expressed genes (for example, OCA2) from within 15q11-q13 when comparing UPD cell lines with controls. However, two genes previously identified as maternally expressed (UBE3A and ATP10C) showed a significant increase in expression in UPD cell lines compared with control and PWS deletion subjects. Several genes/transcripts (for example, GABRA5, GABRB3) had increased expression in UPD cell lines compared with deletion, but less than controls indicating paternal bias. CONCLUSIONS: Our results suggest that differences in expression of candidate genes may contribute to phenotypic differences between PWS subjects with deletion or UPD and warrant further investigations. Chang Gung Med J. 2003 Jun. Prader-Willi syndrome (PWS) is a sporadic disorder of chromosome abnormalities with an estimated prevalence of 1 in 15,000. It mainly affects the central nervous system, and often involves the hypothalamus. Both general and regional anesthesia for these patients is difficult mainly due to morbid obesity. Other common problems include hypotonia, disturbance in thermoregulation, arrhythmia, cor pulmonale, diabetes mellitus, behavior problems, and convulsions. We report on 2 pediatric patients with PWS receiving general anesthesia. The first patient experienced life-threatening episodes of severe hypoxemia in the postanesthesia care unit (PACU) as well as in the pediatric intensive care unit (PICU). Nasal continuous positive airway pressure (CPAP) was suggested by the pediatric pulmonary medicine specialist, and thereafter the patient's condition improved. The clinical course of the second patient was uneventful except for transient intermittent episodes of bronchospasms during emergence. In addition, we discuss differences between these 2 cases and our strategy for the prevention of perioperative complications for PWS patients in the future. Am J Med Genet A. 2003 Jun 1. Coenzyme Q10 (CoQ10) is an essential component of the mitochondrial respiratory chain and an important scavenger of reactive oxygen species. Low levels are found in individuals with reduced energy expenditure, cardiac and skeletal muscle dysfunction, and mitochondrial disorders, many of these manifestations are seen in individuals with Prader-Willi syndrome (PWS). In addition, CoQ10 supplementation frequently is given to individuals with this syndrome. To determine if CoQ10 levels are decreased in PWS, we studied plasma CoQ10 levels in 16 subjects with PWS, 13 with obesity of unknown cause, and 15 subjects without obesity but of similar age and compared with body composition. Plasma CoQ10 levels were significantly decreased (P < 0.05), using several statistical approaches in subjects with PWS (0.45 +/- 0.16 microg/ml), compared to subjects without obesity (0.93 +/- 0.56 microg/ml), but not different from subjects with obesity (0.73 +/- 0.53 microg/ml). When plasma CoQ10 was normalized relative to cholesterol, triglyceride, and creatinine levels and fat and lean mass [determined by dual energy X-ray absorptiometry (DEXA)] in the subjects with either PWS or obesity, no significant differences were observed. However, a lower muscle mass was found in the PWS subjects. J Clin Endocrinol Metab. 2003 May. The objective of this study was to investigate the effects of GH administration on pulmonary function, sleep, behavior, cognition, linear growth velocity, body composition, and resting energy expenditure (REE) in children with Prader-Willi syndrome. The study used a 12-month, balanced, randomized, double-blind, placebo-controlled, cross-over experimental design. Twelve subjects were randomized to GH (0.043 mg/kg x d) or placebo intervention for 6 months and then crossed over to the alternate intervention for 6 months. Differences in outcome variables were determined by paired t tests. Peak flow rate, percentage vital capacity, and forced expiratory flow rate improved and number of hypopnea and apnea events and duration of apnea events trended toward improvement after GH intervention. The only difference in cognition or behavior was an increase in hyperactivity scale on the Behavior Assessment System for Children after GH intervention. Linear growth velocity, REE, and lean mass were higher (67%, 19%, and 7.6%, respectively), and fat mass and percentage body fat were lower (10.3% and 8.1%, respectively) after GH intervention. GH administration did not change mean fasting ghrelin concentration. GH intervention improved body composition and REE and may contribute to better sleep quality and pulmonary function. Eur J Pediatr. 2003 May. Genital abnormalities and disorders of pubertal development such as hypogonadism are common in Prader-Willi Syndrome (PWS). Depending on age, PWS patients present genital hypoplasia and delayed or incomplete gonadal maturation. Nevertheless, only a few evaluations have been made of these findings in this syndrome; in the cases previously reported the diagnosis of PWS has often been based only on clinical criteria and not confirmed by genetic analysis. In this paper we describe both external genital findings and spontaneous pubertal development in 84 patients aged from 2.1 to 35.4 (42 males, 42 females) affected by PWS. Diagnosis was made using the Holm and Cassidy criteria and was confirmed by genetic analysis (methylation test and/or FISH). We evaluated the presence of cryptorchidism, scrotal development, length of penis and volume of testis in males and outlook of labia minora and/or clitoris, age of menarche and features of menses (when present) in females; in both sexes we also evaluated the onset of puberty. All recruited males showed cryptorchidism, which was bilateral in 36 out of 42 patients (86%); 38 patients (90%) underwent orchidopexy. Small testes and scrotal hypoplasia were present in 76% and 69% of cases, respectively. In 76% of females, hypoplasia or absence of labia minora and/or clitoris was described. Spontaneous menarche occurred only in 14/32 cases (44%) over the age of 15 years, but menstrual cycles were often a periodical vaginal spotting. Primary amenorrhea was diagnosed in 56% of cases. Isolated premature pubarche was present in six males and in six females (14% of cases) while one male and two females were affected by precocious puberty (3.6%). Conclusion: Hypogonadism represents a common clinical feature in PWS, confirming the importance of such a major diagnostic criterion. Cryptorchidism was consistently present in all our cases. Patients with PWS commonly fail to spontaneously complete puberty, although some patients may have early pubarche or, more rarely, precocious puberty. In older subjects, hormonal replacement therapy is not always necessary and it must be reserved for selected patients. J Pediatr. 2003 Feb. OBJECTIVE: To evaluate the frequency of cancers recorded by the Surveillance, Epidemiology, and End Results (SEER) Program in persons with Prader-Willi syndrome (PWS) METHODS: A survey was mailed in 1994 to 1852 registrants of the PWS Association (USA) inquiring about a diagnosis of any type of benign tumor or cancer (malignant tumor or leukemia). The risk of developing cancer was then estimated by comparing the observed number of cancers in the PWS population during 1975 to 1994 to the expected number in the general US population using data from the 1971-1994 SEER Cancer Statistics Review. RESULTS: Of the 1852 persons, 1160 (63%) responded, or 75% (1160/1552) of those who received the survey. The total number of observed cancer cases in the PWS study population was 8 versus 4.80 expected in the general US population (P =.1610). Three cases of myeloid leukemia were observed versus 0.075 leukemias expected (P =.0001). CONCLUSIONS: There appears to be an increased risk of myeloid leukemias, but not other cancers, among persons with PWS. Psychol Med. 2003 Jan. BACKGROUND: Prader-Willi syndrome (PWS) is a genetic disorder resulting in obesity, short stature, cryptorchidism, learning disabilities (mental retardation) and severe neonatal hypotonia. Associated with the syndrome are a number of behaviours that are sufficiently distinctive that the syndrome is considered to have a specific 'behavioural phenotype'. METHODS: Through multiple sources we attempted to identify all people with PWS living in one region in the U K. This cohort was augmented by people with PWS from other regions, and a contrast group of people with learning disabilities of varied aetiologies. The main carers were interviewed, using structured and semi-structured interview schedules, to establish the presence and severity of specific behaviours, and PWS diagnostic criteria. The intellectual functioning and attainments of all were determined. Blood samples were obtained for genetic diagnosis from all consenting participants. RESULTS: Although excessive eating was recognized as a potentially severe problem in those with PWS, it was almost universally controlled by food restriction, and therefore not seen as a 'problem behaviour'. Those with PWS differed from a learning disabled group of other aetiologies in the prevalence rates of skin picking, temper tantrums, compulsive behaviours and mood fluctuations, and also in the profile of their adaptive behaviours. CONCLUSIONS: The study confirms the distinct behavioural phenotype of PWS. Specific behaviours occurred significantly more frequently in PWS, compared with an age and BMI matched learning disabled comparison group. A factor analysis of the behaviours involved resulted in three factors that we hypothesized to be independent, and to arise from different mechanisms. J Clin Endocrinol Metab. 2003 Jan. Ghrelin, an endogenous ligand of the GH secretagogue receptor, stimulates appetite and causes obesity in animal models and in humans when given in pharmacologic doses. Prader-Willi Syndrome (PWS) is a genetic obesity syndrome characterized by GH deficiency and the onset of a voracious appetite and obesity in childhood. We, therefore, hypothesized that ghrelin levels may play a role in the expression of obesity in this syndrome. We measured fasting serum ghrelin levels in 13 PWS children with an average age of 9.5 yr (range, 5-15) and body mass index (BMI) of 31.3 kg/m2 (range, 22-46). The PWS group was compared with 4 control groups: 20 normal weight controls matched for age and sex, 17 obese children (OC), and 14 children with melanocortin-4 receptor mutations (MC4) matched for age, sex, and BMI, and a group of 3 children with leptin deficiency (OB). In non-PWS subjects, ghrelin levels were inversely correlated with age (r = 0.36, P = 0.007), insulin (r = 0.55, P < 0.001), and BMI (r = 0.62, P < 0.001), but not leptin. In children with PWS, fasting ghrelin concentrations were not significantly different compared with normal weight controls (mean +/- SD; 429 +/- 374 vs. 270 +/- 102 pmol/liter; P = 0.14). However, children with PWS did demonstrate higher fasting ghrelin concentrations (3- to 4-fold elevation) compared with all obese groups (OC, MC4, OB) (mean +/- SD; 429 +/- 374 vs. 139 +/- 70 pmol/liter; P < 0.001). In conclusion, ghrelin levels in children with PWS are significantly elevated (3- to 4-fold) compared with BMI-matched obese controls (OC, MC4, OB). Elevation of serum ghrelin levels to the degree documented in this study may play a role as an orexigenic factor driving the insatiable appetite and obesity found in PWS. CNS Drugs. 2003. Although people with intellectual disabilities are at increased risk for psychiatric disorders, the type and rate of these problems differ between those with different causes for their retardation. In this paper, we review behavioural and psychiatric problems in persons with Prader-Willi syndrome, a disorder caused by a paternally derived deletion at chromosome 15(q11-q13) in about 70% of affected patients, and by maternal uniparental disomy in the majority of the remaining patients. In addition to the syndrome's characteristic hyperphagia and food seeking, individuals with Prader-Willi syndrome also have increased risks of nonfood, compulsive behaviours. These include skin picking, which is highly prevalent, as well as more variable rates of hoarding, redoing and concerns with symmetry, exactness, cleanliness, ordering and arranging. Relative to others with mental retardation, persons with Prader-Willi syndrome are at a marked increased risk for developing full-blown, obsessive-compulsive disorder. In addition, many people with Prader-Willi syndrome show increased rates of tantrums, oppositionality and aggression. Recent findings suggest that they also have an increased risk of psychotic disorder or affective illness with a psychotic component, especially young adult patients and those with the maternal uniparental disomy as opposed to paternal deletion. Dietary approaches include a reduced-calorie diet and increased physical activity, as well as close supervision around food and keeping food locked away. To date, neither CNS stimulants nor anorectic agents have been effective in treating hyperphagia, in part because hyperphagia in Prader-Willi syndrome is attributed to decreased satiation as opposed to increased hunger. Treatment for compulsivity and maladaptive behaviours include: behavioural programming; a structured, predictable routine; extra help with transitions; family support; and pharmacotherapy. Although formal drug studies have yet to be conducted, SSRIs have been effective in reducing skin picking, compulsivity and aggressive episodes in some individuals with Prader-Willi syndrome. Atypical antipsychotics have also proven helpful in persons with psychotic features or extreme aggression and impulsivity. Largely on the basis of case studies, the risks and benefits of these and other drugs in Prader-Willi syndrome are reviewed. Drug trials that move beyond case studies and that assess the relative efficacy of behavioural treatments alone or in combination with pharmacotherapy are sorely needed. [ 2007 | 2006 | 2005 | 2004 | 2003 | 2002 | 2001 | 2000 | 1999 | 1998 | 1997 | 1996 | 1995 | 1994 | 1993 | 1992 | 1991 | 1990 | 1980-1989 | 1979 and prior ] |