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Biomedical subjects

N C Nevin

Publications and source records attributed to N C Nevin.

At least 145 records · Page 8Linked to original sources
PubMed1989

MEN 2A: update on the Northern Ireland and Australian family.

The Northern Ireland/Australian family with multiple endocrine neoplasia type 2A (MEN 2A) originally described in 1987 is presented with a revised and enlarged pedigree. Four members of the first generation studied have died. A seventh member of the second generation studied has developed medullary thyroid carcinoma and has progressed to surgery. None of the third generation members studied has shown any conclusive abnormality in metabolic screening tests. Each member of the third and fourth generations has had genetic counseling and (if appropriate) DNA analysis with gene probes close to the MEN 2A gene locus on chromosome 10. All members of this highly penetrant family have remained asymptomatic for their disease.

Adult↗
PubMed1988

Prevention and avoidance of congenital malformations.

Many congenital abnormalities do not have either a Mendelian pattern of inheritance or an identifiable chromosome abnormality and are described as 'multifactorial' as it is assumed they are determined by several genes, each with added effects and modified to a greater or lesser extent by environmental factors. They include spina bifida and anencephaly, cleft lip or cleft palate or both, congenital heart defect and congenital dislocation of the hip, and they constitute a major community health problem. Developments in genetics, biochemistry and cytogenetics have presented new approaches to the prevention and avoidance of congenital abnormalities. The approaches available for the avoidance of congenital malformations include the avoidance of harmful environmental factors, the screening of the newborn and early treatment, genetic counselling and antenatal monitoring with selective termination. The prevention of neural-tube defects in 'high risk' mothers can be achieved by periconceptional vitamin supplementation. In Northern Ireland, of 438 fully supplemented women, only 4 (0.98%) infants or fetuses among 407 infants and fetuses examined had a neural-tube defect, whereas of 356 unsupplemented women, 16 (4.7%) infants or fetuses among 337 infants or fetuses examined had a neural-tube defect.

Congenital Abnormalities↗
PubMed1988

Expression of chromosome 21 specific sequences in normal and Down's syndrome tissues.

Using RNA isolated from age and sex matched normal and Down's Syndrome foetal liver and brain tissues, Northern blots were prepared and probed with 4 chromosome 21 specific sequences. The results show that no consistent pattern of expression emerges when Down's Syndrome tissue is compared with normal tissue but the results are very different from the 3/2 ratio of expression which may be expected. Two sequences 21.3 and 26C show only minor differences in expression in trisomy 21 liver samples but significant changes in their expression pattern when normal and Down's Syndrome brain samples are compared. The other sequences, JG77 and JG90 show a 5 fold higher degree of expression in Down's brain but when liver samples are compared one of these sequences shows equal levels of expression in normal and Down's Syndrome samples and the other shows a decrease in expression level in Down's Syndrome samples.

Animals↗
PubMed1988

Characterization of human skin fibroblast extracellular proteins by two-dimensional polyacrylamide gel electrophoresis.

Human skin fibroblasts secrete over 50 proteins into the culture medium. In this paper these are characterised using two-dimensional polyacrylamide gel electrophoresis and peptide mapping of proteins metabolically labelled in the presence and absence of tunicamycin. Thirty of these proteins have been shown to be N-glycosides, 4 are O-glycosides and 10 are not glycosylated. Of the major proteins, groups 1-4 have previously been shown to be fibroblast specific. Peptide mapping and tunicamycin treatment has identified that groups 1 and 2, and 3 and 4 are closely related and that groups 1 and 3 arise by N-glycosylation of 2 and 4, respectively. The unglycosylated precursor forms of several other proteins have also been identified. This approach to the analysis of protein secretion provides an abundance of information on many proteins simultaneously and can be used to assess the changes in protein secretion associated with development, and to identify extracellular growth factors and other regulatory proteins.

Adult↗
PubMed1988

Familial expansile osteolysis. A new dysplasia.

We report 40 cases in one family of an autosomal dominant bone dysplasia, which, though similar in some aspects to Paget's disease, seems unique in some features and in its natural history. The disease shows both general and focal skeletal changes, the latter being mainly in the limbs with an onset from the second decade. Progressive osteoclastic resorption is accompanied by medullary expansion which leads to pain, severe deformity and a tendency to pathological fracture. The serum alkaline phosphatase and urinary hydroxyproline are variably elevated, while other biochemical indices are normal. Most patients had an associated deafness of early onset and loss of dentition. No previous description of this disease has been found in the literature.

Deafness↗
PubMed1986

Syndrome of short stature, microcephaly, mental retardation, and multiple epiphyseal dysplasia--Lowry-Wood syndrome.

We describe a brother and a sister with a syndrome of short stature, microcephaly, mental retardation, and multiple epiphyseal dysplasia. The parents were normal. This appears to be the second example of the syndrome first described by Lowry and Wood [1975] in two boys who had epiphyseal dysplasia, short stature, microcephaly, and nystagmus; one of these patients was mildly mentally retarded. The Lowry-Wood syndrome probably is an autosomal recessive trait.

Bone and Bones↗
PubMed1986

Recurrent neural tube defects, risk factors and vitamins.

Data from our trial of periconceptional vitamin supplementation for the prevention of neural tube defects have been analysed to assess the influence of various factors on recurrence rates of neural tube defect. Our data suggest that the risk of recurrence of neural tube defect is influenced by the number of previous neural tube defects, area of residence, immediately prior miscarriage, and interpregnancy interval. None of these factors, however, contributed any significant differential risk between supplemented and unsupplemented mothers. Hence we conclude that the highly significant difference in recurrence rates of neural tube defect between supplemented and unsupplemented mothers was due to vitamin supplementation.

Abortion, Spontaneous↗
PubMed1986

Duchenne muscular dystrophy in a female with a translocation involving Xp21.

A female with Duchenne muscular dystrophy, diagnosed at the age of 3 years 8 months, is reported. Chromosome studies revealed an X;autosome reciprocal translocation t(X;5) (p21.2;q31.2). With the BrdU-Hoechst 33258-Giemsa technique, there was nonrandom preferential inactivation of the normal X. Our patient is the ninth reported case of Duchenne muscular dystrophy associated with an X;autosome translocation. In all cases the breakpoint in the X chromosome is in band p21 at or near the site of the DMD gene.

Chromosome Banding↗
PubMed1985

The role of periconceptional vitamin supplementation in the prevention of neural tube defects.

The British Isles multicentre study of periconceptional vitamin supplementation in women with a previous infant with an NTD has demonstrated an apparent beneficial effect in reducing risk of recurrence of an NTD. In Northern Ireland, a similar significant effect has been observed with a reduction of the recurrence risk from 5.2% in unsupplemented to 0.7% in fully supplemented women. The problems and implications of periconceptional vitamin supplementation in the prevention of NTDs are discussed.

Clinical Trials as Topic↗
PubMed1984

Differences in proteins secreted by human fibroblasts and muscle cells in culture.

Cell cultures of human skin fibroblasts, myoblasts, and fused muscle cells were grown in the presence of [14C]leucine or a mixture of [14C]amino acids. The proteins synthesised and secreted or leaked into the culture medium during radio-labelling were separated by one- and two-dimensional PAGE and detected by fluorography. Four major bands of Mr 54 kD, 52 kD, 51 kD, and 49 kD were present at greatly increased concentration in fibroblast media. These fibroblast-specific polypeptides can be readily detected in myoblast/fibroblast cocultures with fibroblast content as low as 5%.

Amino Acids↗
PubMed1984

Periconceptional vitamin supplementation and the prevention of neural tube defects in south-east England and Northern Ireland.

A comparison has been made of the effectiveness of periconceptional vitamin supplementation for the prevention of recurrence of neural tube defects (NTD) in south-east England and Northern Ireland. These areas represent the extremes of birth prevalence of NTD (low and high respectively) within the United Kingdom. Vitamin therapy resulted in a slightly less than two-fold reduction in the recurrence risk in south-east England and a greater than three-fold reduction in Northern Ireland, when compared with unsupplemented women at the same risk from the two areas. It is probable that one of the recurrences in each area did not involve the multifactorial form of NTD and, if these are excluded, then the reduction in recurrence risk with vitamin supplementation is 2.4 times in south-east England and 5.4 times in Northern Ireland. Either way, beneficial effects of supplementation are apparent in both areas but are more marked in the high prevalence area. The implications of this for the future are discussed. Two other important findings were that all but one of the recurrences of NTD with full supplementation occurred in male fetuses, and there was a higher than expected occurrence of isolated hydrocephalus in infants or fetuses following full supplementation.

Female↗
PubMed1983

Further experience of vitamin supplementation for prevention of neural tube defect recurrences.

In accordance with a previous protocol, a second cohort of 254 mothers with a history of previous neural tube defect (NTD) births was before a subsequent conception and continued until the time of the second missed menstrual period. There were 2 NTD recurrences (0.9% of 234 infants/fetuses examined), which is significantly fewer than the 11 NTD recurrences (5.1% of 215 infants/fetuses examined) born to 219 unsupplemented (US) mothers in the same centres over the same period. When the data for the two cohorts were combined, the overall recurrence rates were 0.7% for 454 fully supplemented (FS) mothers and 4.7% for 519 US mothers. The recurrence rates after 1 previous NTD were 0.5% for FS and 4.2% for US mothers: after 2 or more previous NTDs, 2.3% for FS and 9.6% for US. There were no recurrences among the offspring of a further 114 mothers whose duration of supplementation fell short of the full regimen (partially supplemented, PS).

Female↗
PubMed1983

Cystic hygroma simulating an encephalocele.

An ultrasound examination at 17 weeks gestation on a woman with a family history of spina bifida suggested that the fetus had a closed encephalocele. Amniotic fluid alphafetoprotein, rapidly adhering cells and acetylcholinesterase gel electrophoresis were normal. The pregnancy was terminated and the fetus was found to have a large cystic hygroma. It is suggested that in counselling parents of an infant or fetus with a cystic hygroma and with a normal chromosome constitution, ultrasound examination in future pregnancies is advisable, because of the possibility of autosomal recessive inheritance.

Adult↗