PubMed Health⌕ Search

Biomedical subjects

M G Butler

Publications and source records attributed to M G Butler.

At least 109 records · Page 6Linked to original sources

Prader-Willi syndrome: consensus diagnostic criteria.

The diagnosis of Prader-Willi syndrome (PWS) is based on clinical findings that change with age. Hypotonia is prominent in infancy. Obesity, mild mental retardation or learning disability, and behavior problems, especially in association with food and eating, result in a debilitating physical and developmental disability in adolescence and adulthood. No consistent biological marker is yet available for PWS in spite of recent research activity in cytogenetics and molecular genetics. Diagnostic criteria for PWS were developed by consensus of seven clinicians experienced with the syndrome in consultation with national and international experts. Two scoring systems are provided: one for children aged 0 to 36 months and another one for children aged 3 years to adults. These criteria will aid in recognition of the syndrome in hypotonic infants and in obese, mildly retarded, behaviorally disturbed adolescents and adults. They will also ensure uniform diagnosis for future clinical and laboratory research in PWS.

Adolescent↗

The frequency of uniparental disomy in Prader-Willi syndrome. Implications for molecular diagnosis.

BACKGROUND: Prader-Willi syndrome is a genetic disorder characterized by infantile hypotonia, obesity, hypogonadism, and mental retardation, but it is difficult to diagnose clinically in infants and young children. In about two thirds of patients, a cytogenetically visible deletion can be detected in the paternally derived chromosome 15 (15q11q13). Recently, patients with Prader-Willi syndrome have been described who do not have the cytogenetic deletion but instead have two copies of the 15q11q13 region that are inherited from the mother (with none inherited from the father). This unusual form of inheritance is known as maternal uniparental disomy. Using molecular genetic techniques, we sought to determine the frequency of uniparental disomy in Prader-Willi syndrome. METHODS: We performed molecular analyses using DNA markers within 15q11q13 and elsewhere on chromosome 15 in 30 patients with Prader-Willi syndrome who had no cytogenetically visible deletion. We also studied their parents. Three patients with Prader-Willi syndrome who had a cytogenetic deletion served as controls. RESULTS: In 18 of the 30 patients without a cytogenetic deletion (60 percent), we demonstrated the presence of maternal uniparental disomy for chromosome 15 and its association with advanced maternal age. In another eight patients (27 percent), we identified large molecular deletions. The remaining four patients (13 percent) had evidence of normal biparental inheritance for chromosome 15; three of these patients were the only ones in the study who had some atypical clinical features. CONCLUSIONS: In about 20 percent of all cases, Prader-Willi syndrome results from the inheritance of both copies of chromosome 15 from the mother (maternal uniparental disomy). With the combined use of cytogenetic and molecular techniques, the genetic basis of Prader-Willi syndrome can be identified in up to 95 percent of patients.

Adult↗

Local production of fibronectin by ectopic human retinal cells.

The distribution of fibronectin mRNA and fibronectin in adult human retina and epiretinal membranes was investigated by in situ hybridisation and immunohistochemical techniques. The cells in normal adult retina contained little or no fibronectin mRNA and the retina only showed fibronectin immunoreactivity in retinal vessels. The cells in detached neuroretina did not contain fibronectin message but the vitreoretinal interface of the detached retina exhibited variable fibronectin immunoreactivity. Retinal glia, retinal pigment epithelium and fibroblast-like cells in membranes at the vitreoretinal juncture (epiretinal membranes) showed variable labelling with the fibronectin mRNA probe and all the membranes immunostained for fibronectin. No difference could be detected between membrane cell types in the intensity of labelling with the mRNA probe or for fibronectin immunoreactivity. The results indicate that cells in situ in attached and detached adult human retina do not produce fibronectin. Although fibronectin at the vitreoretinal juncture in retinal detachment is probably partly derived from plasma fibronectin resulting from breakdown of the blood-retinal barrier, ectopic retinal cells produce fibronectin and contribute to the glycoprotein epiretinal membranes.

Adolescent↗

Cytogenetic abnormalities in a rare case of giant cell osteogenic sarcoma.

The cytogenetic analysis of a rare, nonirradiated case of giant cell tumor of bone with osteogenic sarcoma transformation is presented for the first time in a 19-year-old female. Telomeric associations involving 4p, 8p, 11p, 14p, 17p, 17q, and 20q were observed. Additionally, monosomy 13, 11p abnormalities and marker chromosomes were identified in tumor cells. Chromosome 11 involvement, particularly 11p translocations and 11p telomeric associations, were frequently observed in the tumor cells obtained from our patient, which suggests that chromosome 11p may play a role in the development of giant cell osteogenic sarcoma.

Adolescent↗

Keratan sulphate in rheumatoid arthritis, osteoarthritis, and inflammatory diseases.

Serum concentrations of antigenic keratan sulphate determined by an enzyme linked immunosorbent assay (ELISA) with a monoclonal antibody were studied in patients with rheumatoid arthritis (RA), osteoarthritis, ankylosing spondylitis, other inflammatory diseases, and a large control group of women without arthritis. Mean keratan sulphate concentrations were low in 117 women with RA compared with 227 female control subjects matched for age drawn from a community survey. There were significant correlations between serum keratan sulphate concentrations in patients with RA and serum C reactive protein and the erythrocyte sedimentation rate. Serum keratan sulphate concentrations were also low in 29 men and women with ankylosing spondylitis and 29 patients with arthritis and high concentrations of C reactive protein. In 98 women undergoing an operation for benign breast disease there were decreases in serum keratan sulphate concentrations after the operation which correlated with doses in serum C reactive protein. No differences were found in keratan sulphate concentrations in 137 women with osteoarthritis compared with controls. Within the group with osteoarthritis there were no differences for the various joint groups and there was no obvious correlation with radiographic severity or progression. These findings suggest serum keratan sulphate is unlikely to be useful as a diagnostic marker in osteoarthritis or RA but indicate a role for inflammation in the regulation of cartilage loss.

Acute-Phase Reaction↗

Localisation of fibronectin mRNA in the rheumatoid synovium by in situ hybridisation.

The distribution of fibronectin, an extracellular matrix glycoprotein which plays a part in fibrosis and tissue repair, has previously been described using immunohistochemical methods. These do not differentiate between locally synthesised and plasma derived fibronectin. In this work the distribution of cells actively synthesising fibronectin was assessed by in situ hybridisation using a radiolabelled antisense RNA probe in synovial biopsy samples from patients with rheumatoid arthritis, osteoarthritis, ankylosing spondylitis, and control subjects without inflammatory disease. Large amounts of fibronectin mRNA were found specifically in synovial lining cells, providing evidence for the local production of fibronectin in the synovium. Levels of fibronectin mRNA were variable between patients. These differences were not related to the diagnosis or to the subintimal inflammatory cell infiltrate; where there was synovial lining cell hyperplasia there was a concomitant increase in the number of cells containing fibronectin mRNA, which was consistent with increased levels of immunoreactive fibronectin at this site. Increased levels of fibronectin in synovial fluid in patients with rheumatoid arthritis may be due to an increased number of lining cells secreting the protein, rather than upregulation of the gene by these cells.

Aged↗

Fibronectin synthesis in subretinal membranes of proliferative vitreoretinopathy.

In situ hybridisation and immunohistochemical studies were conducted on six surgically excised subretinal membranes of proliferative vitreoretinopathy to investigate whether displacement of retinal pigment epithelial and glial cells to subretinal membranes was associated with fibronectin production by the subretinal membrane cells. Fibronectin messenger RNA (mRNA) and fibronectin immunoreactivity were observed in some cells in all of the subretinal membranes studied and up to 30% of the cells in individual specimens showed intense labelling for fibronectin mRNA. The results support the concept that the cells in subretinal membranes produce fibronectin. Locally produced fibronectin may play a role in subretinal membrane cohesion, and displacement of retinal pigment epithelial and glial cells from their normal location may induce the cells to manufacture fibronectin. Fibronectin production may be more prominent in migrating subretinal cells.

Eye Diseases↗

Standards for selected anthropometric measurements in males with the fragile X syndrome.

Standards (95th, 50th, and 5th percentiles) in fragile X syndrome for weight, height, head circumference, ear length, and testicular volume are reported. For comparison with fragile X syndrome standardized curves, normal control data from the literature were similarly plotted and curves produced. These standards reflect the physical parameters that are frequently abnormal in males with the fragile X syndrome and should be useful in the medical management of patients with this syndrome. The standards may also be used to help identify those individuals, particularly the younger males, for chromosome studies to confirm the clinical impression of the fragile X syndrome.

Adolescent↗

Telomeric associations and consistent growth factor overexpression detected in giant cell tumor of bone.

Tumor specimens from 15 patients with giant cell tumor (GCT) of bone were cytogenetically analyzed. A subset of five individuals had tumor cells harvested and polyadenylated RNA isolated. Multiple Northern blots were performed utilizing radiolabeled probes for the growth factors TGF beta 1, TGF beta 2, TGF beta 3, and TGF alpha (TGF, transforming growth factor). RNAs from other types of neoplasms and nonneoplastic cells were examined as controls. The most consistent cytogenetic abnormality detected involved multiple telomeric associations (TAs), most frequently involving the terminus of the long arm of chromosome 19 (19q). Northern blot analysis revealed a consistent expression of TGF beta 1 and TGF beta 2 with an inconsistent mRNA expression for the other TGFs. There was a relative overexpression of mRNA for TGF beta 2. The gene location for TGF beta 1 is near the 19q terminus and thus it is speculated that TGF beta may play a role in the neoplastic transformation of GCT.

Adult↗

Hereditary lymphedema and distichiasis.

Two patients with lymphedema-distichiasis syndrome illustrate that both Milroy's disease and late-onset hereditary lymphedema are sometimes associated with distichiasis. It is important for ophthalmologists to be aware of the lymphedema-distichiasis syndrome because of its ophthalmic manifestations and the associated systemic abnormalities that can be potentially life threatening.

Adolescent↗

An infant with deletion of the distal long arm of chromosome 15 (q26.1----qter) and loss of insulin-like growth factor 1 receptor gene.

We report on an infant with a previously undescribed chromosome 15 deletion (q26.1----qter) and compare the clinical findings with those of 7 reported patients with deletions of distal 15q, as well as ring chromosome 15 syndrome patients. Most of the patients with deletions of distal 15q, including our patient, have intrauterine growth retardation (IUGR), microcephaly, abnormal face and ears, micrognathia, highly arched palate, renal abnormalities, lung hypoplasia, failure to thrive, and developmental delay/mental retardation. Several genes have been assigned to the 15q25----qter region, including insulin-like growth factor 1 receptor (IGF1R). DNA analysis from our patient documented the loss of one IGF1R gene copy. Our study further localizes the IGF1R gene distal to the 15q26.1 band. It is interesting to speculate that the severe IUGR and postnatal growth deficiency of our patient and other patients with similar chromosome 15 deletions are related to the loss of an IGF1R gene copy which may lead to an abnormal number and/or structure of the receptors.

Chromosome Banding↗

Reliability of ultrasound in the prenatal diagnosis of urinary tract abnormalities.

To investigate the ability of ultrasonography to detect urinary tract abnormalities prenatally, we reviewed the records of 26 pregnancies diagnosed by prenatal ultrasound to have urinary tract anomalies. We compared the prenatal diagnoses with postnatal renal and urinary tract pathology. This comparison showed different degrees of agreement for different prenatal diagnoses (2 individuals had more than one diagnosis): 4 of 8 for multicystic kidneys, 1 of 1 for polycystic kidney disease, 1 of 2 for renal agenesis, 6 of 7 for ureteropelvic junction obstruction, 1 of 3 for posterior urethral valves, 4 of 5 for no pathology noted, and 2 of 2 for other abnormalities. Prenatal diagnosis and postnatal findings were in agreement in 68% of cases. Varying levels of diagnostic reliability should be considered when managing pregnancies complicated by fetal urinary tract abnormalities and subsequent postnatal evaluation and diagnosis. Further efforts are needed to improve on the techniques and reliability of prenatal diagnosis of urinary tract abnormalities.

Female↗

Anthropometric study with emphasis on hand and foot measurements in the Prader-Willi syndrome: sex, age and chromosome effects.

Age, sex and chromosome effects on weight, height, sitting height, three head dimensions, and five hand and three foot measurements were analyzed from 57 patients (35 males and 22 females) with the Prader-Willi syndrome (PWS). No significant differences were observed in anthropometric data between PWS patients with the 15q chromosome deletion and those with normal chromosomes. Preschool children were found to have dolichocephaly, while hand and foot measurements, stature and sitting height were within normal range, although foot size was smaller than hand size in females when compared with PWS males. However, anthropometric measurements, excluding weight, head length and ankle breadth, were less than -2 SD in adult patients. Abnormal growth patterns apparently exist with significant negative correlations with age, particularly in PWS males, for height, sitting height, head circumference, and hand and foot measurements, but a significant positive correlation for weight was found in patients below 10 years of age.

Adolescent↗

A 15-item checklist for screening mentally retarded males for the fragile X syndrome.

A 15-item checklist, including physical and behavioral features frequently observed in fragile X syndrome, was used in a prospective study of 188 mentally retarded males in order to identify males at risk for this syndrome. Of the 188 males, 19 were found to have the fragile X syndrome, while the remaining 169 males had no recognizable cause of their mental retardation, including normal chromosomes. Significant differences (p less than 0.01) were found between mentally retarded males with and without the fragile X syndrome with increased hyperactivity; shorter attention span; more tactile defensiveness, hand-flapping, perseverative speech, and hyperextensibility; large ears and testes; higher frequency of simian creases or Sydney lines and plantar creases; and more positive family histories of mental retardation in the fragile X syndrome males. Multiple regression and discriminant analyses of the 188 males indicated several physical features were useful predictors for inclusion in the fragile X syndrome group. An overall correct classification rate of 93% was achieved based on 6 variables (plantar crease, simian crease, hyperflexibility, large testes, large ears, and a positive family history of mental retardation) that were entered into the discriminant equation. Therefore, our experience with a 15-item checklist suggests the potential of screening for the fragile X syndrome in mentally retarded males and that 6 of the 15 variables were particularly good predictors of this syndrome.

Adolescent↗

Standards for selected anthropometric measurements in Prader-Willi syndrome.

We report standards (95th, 50th, and 5th centiles) in Prader-Willi syndrome for weight, height, sitting height, head circumference, head length, head breadth, hand length, middle finger length, palm length, hand breadth, foot length, foot breadth, triceps skinfold, and subscapular skinfold. For comparison with Prader-Willi syndrome standardized curves, normal control data from the literature were plotted similarly and standard curves were produced. We encourage the use of these standards with the examination of patients who have Prader-Willi syndrome and in the comparison of the patient who has Prader-Willi syndrome with other similarly affected individuals. The standards may also be useful for assisting in the diagnosis of Prader-Willi syndrome, particularly in younger individuals.

Adolescent↗