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C R Paterson

Publications and source records attributed to C R Paterson.

At least 19 recordsLinked to original sources
PubMed1999

A randomized comparison of driver reaction time after open and endoscopic tension-free inguinal hernia repair.

BACKGROUND: The aim of this study was to assess whether prosthetic tension-free inguinal hernia repair would cause less impairment of reaction times, thus allowing an earlier return to driving than previously recommended after conventional hernia repair. METHODS: Driver reaction times were measured in 64 patients randomized to open tension-free repair or totally extraperitoneal endoscopic inguinal hernia repair. Measurements were made preoperatively and on postoperation days 1, 3, and 6. RESULTS: In the endoscopic group, there was a gradual improvement in hand and foot reaction times over the days tested. In the open group, there was a slowing in both hand and foot reaction times on postoperation days 1 and 3. The difference in foot reaction times between the open and endoscopic groups was significant on these days (p = 0.01 and 0.003, respectively). By day 6, the foot reaction times in the open group were slightly faster than before surgery. CONCLUSIONS: After prosthetic tension-free inguinal hernia repair, patients can return to driving 1 week after the operation.

Automobile Driving↗
PubMed1999

Novel mutations in the 1alpha-hydroxylase (P450c1) gene in three families with pseudovitamin D-deficiency rickets resulting in loss of functional enzyme activity in blood-derived macrophages.

Pseudovitamin D-defiency rickets (PDDR) is an autosomal recessive disorder characterized by hypocalcemia, rickets (which are resistant to treatment with vitamin D), and low or undetectable serum levels of 1,25-dihydroxyvitamin D (1,25(OH)2D). The symptoms are corrected with 1,25(OH)2D treatment, and the disease is now believed to result from a defect in the cytochrome P450 component (P450c1; CYP27B1) of the renal 25-hydroxyvitamin D-1alpha-hydroxylase (1-OHase). We have studied genomic DNA from three families with PDDR and have identified the same homozygous mutation in the P450c1 gene in two of the index cases, causing a frameshift in exon 8, resulting in a premature stop codon in the heme-binding domain. The two cases in the third kindred were compound heterozygotes with missense mutations in exons 6 and 9. We have also identified a C/T polymorphism in intron 6 of the P450c1 genomic DNA. Interferon gamma-inducible 1-OHase activity in blood-derived macrophages was shown by 1,25(OH)2D synthesis in all control cells tested (37-184 fmol/h/106 cells) and those from the PDDR family parents (34-116 fmol/h/106 cells) but was totally absent from the patients' cells, indicating a defect in their macrophage 1-OHase, similar to the presumed renal defect. The assumption of similarity between the renal and macrophage P450c1 was supported by our ability to clone a 514 bp sequence, including the heme-binding region of the macrophage P450c1 cDNA from controls, which was identical to that published for both the renal and keratinocyte P450c1 cDNAs.

24,25-Dihydroxyvitamin D 3↗
PubMed1998

Evaluation of peripheral dual energy X-ray absorptiometry: comparison with single photon absorptiometry of the forearm and dual energy X-ray absorptiometry of the spine or femur.

An evaluation of the Osteoscan peripheral dual energy X-ray absorptiometer (pDXA) was carried out to compare its performance with those of a single photon absorptiometer (SPA) (Molsgaard Medical ND1100A) and a dual energy X-ray absorptiometer (DXA) (Lunar DPX alpha) of the spine or femur. In 57 patients, correlation between bone mineral content (BMC) of the forearm at the ultradistal (UD) site by pDXA and by SPA was high (r = 0.94). Comparisons were also made with spine and femur bone mineral density (BMD) DXA measurements. The correlation of z-scores of UD BMD with z-scores for lumbar spine L2-L4 was r = 0.63 (n = 73 patients); and with z-scores for neck of femur was r = 0.72 (n = 33). With the Osteoscan the measurement error coefficient of variation in vivo was 2.6% for BMC, 1.8% for BMD at the ultradistal site; 2.1% for BMC and 1.9% for BMD at the mid-distal site. Repeat measurements were made of the European forearm phantom; precision for SPA was slightly better than either pDXA or Lunar DXA. The Osteoscan has the potential for a rapid throughput of patients and is not affected by calcification and degenerative changes that can corrupt DXA measurements on the anteroposterior spine in older women.

Absorptiometry, Photon↗
PubMed1998

Influence of injection site for low-dose heparin on wound complication rates after inguinal hernia repair.

A high incidence of complications related to bleeding was observed after open prosthetic inguinal hernia repair. The site of injection of low-dose heparin into the abdominal wall was thought to be a possible causal factor for these complications. The wound complication rate after repair of primary unilateral inguinal hernias was recorded for 51 patients who had been given abdominal wall injections of heparin. Subsequently the injection site was changed to the upper limb in a further 63 patients and the incidence of wound complications recorded. A significantly higher incidence of haematomas and seromas was found in the abdominal wall injection group (39.2% vs 17.5%, P = 0.01). The role of low-dose heparin prophylaxis in inguinal hernia repair is discussed. We conclude that in those patients receiving heparin prophylaxis the injections should be given at a site remote from the operative area.

Abdominal Muscles↗
PubMed1997

Skin content of 7-dehydrocholesterol in patients with malabsorption.

The mechanism for the development of vitamin D deficiency in patients with malabsorption remains unclear. We wished to examine the hypothesis that one factor was a reduced skin content of 7-dehydrocholesterol, the precursor for the formation of vitamin D in the presence of ultraviolet radiation. We measured 7-dehydrocholesterol in skin samples from 9 patients who had previously had vitamin D deficiency due to malabsorption (6 with Crohn's disease, 2 with primary biliary cirrhosis, and 1 with idiopathic pseudo-obstruction). We found no evidence of reduced levels of 7-dehydrocholesterol in the skin in these patients. Lack of 7-dehydrocholesterol does not contribute to vitamin D deficiency in malabsorption.

Adult↗
PubMed1997

Osteogenesis imperfecta and other heritable disorders of bone.

This chapter summarizes the many recent advances in our understanding of the principal heritable disorders of bone. In the course of little more than a decade many diseases that were recognizable only by their clinical and radiological features have become explicable in molecular terms. Large numbers of mutations of the genes coding for collagen, for alkaline phosphatase, for the cell surface receptors for parathyroid hormone and for calcium, and for a number of other proteins, are recognized. The chapter covers the many variants of osteogenesis imperfecta, the most common heritable cause of fractures. It also covers osteopetrosis, hypophosphatasia, pseudohypoparathyroidism (with Albright's hereditary osteodystrophy), familial benign hypercalcaemia, autosomal dominant hypocalcaemia and the molecular causes of some chondrodysplasias.

Bone Diseases↗
PubMed1996

Causes of death in osteogenesis imperfecta.

AIMS: To determine the causes of death in patients with osteogenesis imperfecta, excluding infants with the perinatal lethal form (type II). METHODS: Seventy nine patients with known osteogenesis imperfecta were identified, 37 of whom had been seen clinically in life. Causes of death were identified from death certificates, postmortem reports, medical records, hospital consultants, relatives, and the Brittle Bone Society's records. RESULTS: Patients with the milder types of osteogenesis imperfecta, I and IV, often had a normal lifespan and died of unrelated illnesses such as myocardial infarction and malignancy. In some of these patients and in many patients with the more severe type III disease, it was clear that osteogenesis imperfecta contributed significantly to death, almost certainly to many of the respiratory deaths and to deaths from cardiac failure due to kyphoscoliosis. Osteogenesis imperfecta also caused six deaths, directly or indirectly, due to basilar invagination of the skull. Osteogenesis imperfecta may have contributed to deaths from intracranial bleeding. Apparently minor traumatic incidents may have disastrous consequences in patients with this disorder. CONCLUSIONS: Prompt care for respiratory infections and prevention of trauma in patients with osteogenesis imperfecta is essential.

Adolescent↗
PubMed1995

Is previous hyperthyroidism still a risk factor for osteoporosis in post-menopausal women?

OBJECTIVE: Hyperthyroidism is a risk factor for osteoporosis, but the relative contributions of the episode of hyperthyroidism and thyroxine replacement for subsequent hyperthyroidism remain uncertain. In this study we have measured bone mineral density (BMD) in post-menopausal women with a previous history of hyperthyroidism, comparing those requiring thyroxine therapy with those remaining euthyroid and with an historical local control population. DESIGN: Cross-sectional study. PATIENTS: One hundred and six post-menopausal women with a previous history of hyperthyroidism. These were divided into four groups: treated with radioiodine, remaining euthyroid (group RU, n = 15); treated with radioiodine, receiving thyroxine for at least 5 years (group RT, n = 46); treated with surgery, remaining euthyroid (group SU, n = 21); treated with surgery, receiving thyroxine for at least 5 years (group ST, n = 24). There were 102 control subjects. MEASUREMENT: Forearm bone mineral density at distal and ultradistal sites as measured by single-photon absorptiometry. RESULTS: Results were expressed as 'Z-scores' i.e. number of standard deviations from the mean of a 5-year age-band from the local control population. Mean Z-scores at distal and ultradistal sites were as follows: -0.61 and -0.81 in group RU; -0.58 and -0.56 in group RT; -0.27 and -0.30 in group SU; -0.81 and -0.57 in group ST. Patients in groups RU, RT and ST but not SU had significantly lower BMD than controls. CONCLUSION: Post-menopausal women with previous hyperthyroidism treated with radioiodine have reduced BMD, whether or not receiving thyroxine. They should be targeted for densitometry and protective therapy with oestrogen should be considered. Those treated with surgery appear to be at less risk; this may be because most are diagnosed and treated whilst premenopausal. Thyroxine may have a deleterious effect in this group; longitudinal studies would provide further clarification.

Aged↗
PubMed1995

Calcium-sensing receptor mutations in familial benign hypercalcemia and neonatal hyperparathyroidism.

Familial benign hypercalcemia (FBH) and neonatal hyperparathyroidism (NHPT) are disorders of calcium homeostasis that are associated with missense mutations of the calcium-sensing receptor (CaR). We have undertaken studies to characterize such CaR mutations in FBH and NHPT and to explore methods for their more rapid detection. Nine unrelated kindreds (39 affected, 32 unaffected members) with FBH and three unrelated children with sporadic NHPT were investigated for mutations in the 3,234-bp coding region of the CaR gene by DNA sequencing. Six novel heterozygous (one nonsense and five missense) mutations were identified in six of the nine FBH kindreds, and two de novo heterozygous missense mutations and one homozygous frame-shift mutation were identified in the three children with NHPT. Our results expand the phenotypes associated with CaR mutations to include sporadic NHPT. Single-stranded conformational polymorphism analysis was found to be a sensitive and specific mutational screening method that detected > 85% of these CaR gene mutations. The single-stranded conformational polymorphism identification of CaR mutations may help in the distinction of FBH from mild primary hyperparathyroidism which can be clinically difficult. Thus, the results of our study will help to supplement the clinical evaluation of some hypercalcemic patients and to elucidate further the structure-function relationships of the CaR.

Amino Acid Sequence↗
PubMed1994

Energy expenditure and body composition in growth hormone deficient adults on exogenous growth hormone.

OBJECTIVES: We assessed whether the obesity observed in growth hormone deficient adults is maintained by a reduction in energy expenditure. We studied the effects of exogenous growth hormone on energy expenditure and body composition. DESIGN: We performed an open study with growth hormone administered at 0.5 units per kilogram ideal body weight per week for 3 months. PATIENTS: Seven growth hormone deficient adults were studied. Thirty-eight healthy volunteers had their resting metabolic rate measured, with seven of them proceeding to have their total energy expenditure assessed. MEASUREMENTS: Total energy expenditure was measured by the doubly labelled water method (D2O18), resting metabolic rate by ventilated hood indirect calorimetry, and fat free mass from the dilution volume of oxygen-18. Body composition and components of energy expenditure were assessed before, at 2 weeks and at the end of the 3-month treatment period on exogenous growth hormone. RESULTS: Growth hormone deficient adults did not have a low total energy expenditure compared to healthy controls (13.12 vs 12.75 MJ/24 h) with only one patient expending less than 10 MJ/24 h. None had a resting metabolic rate lower than the 95% confidence limits of normality. The amount of energy expended on physical activity and thermogenesis was significant (6.54 MJ/24 h) and was similar to healthy controls (6.47 MJ/24 h). Resting metabolic rate increased by 15.9% after 14 days on exogenous growth hormone and was elevated 12.1% after 3 months treatment but the ratio to fat-free mass remained unaltered. Total energy expenditure increased by 13.4% after 14 days therapy. Fat-free mass increased significantly after 3 months treatment by (mean) 4.5 kg with no change in fat mass and no loss in body weight. CONCLUSIONS: Obesity maintenance in growth hormone deficient adults is not a consequence of reduced total energy expenditure or a reduced exercise energy output. There was also no evidence for an energy sparing mechanism. Energy expenditure was increased by exogenous growth hormone but was not associated with a loss in fat mass or body weight suggesting the need for dietetic advice for those already obese at the outset of therapy.

Adult↗
PubMed1994

Bone density in osteogenesis imperfecta may well be normal.

Osteogenesis imperfecta (OI) is often regarded as a form of osteoporosis. However, the bone fragility is the result of defective collagen and earlier work has demonstrated that cortical thickness, in bones not previously fractured, is usually normal. We have now measured the bone mineral content of the distal forearm in 61 adult patients with well characterized OI. Three patients with the Silence type III disorder had bone mass values well below the reference interval. For the 47 type I patients and 11 type IV patients, the bone mass was significantly lower than normal (P < 0.001). However 70% of patients had values within the reference interval. One cannot therefore exclude the diagnosis of OI by finding normal values with densitometry. Diagnostic difficulties do not occur in type III patients and our main objective was to recruit as many individuals as possible with OI types I and IV. In the type IV disease, the diagnosis can be particularly difficult without a positive family history. Since the evaluation of bone density by subjective examination of radiographs is a much less precise procedure, most patients with type I and IV OI would be expected to have 'normal' appearances with this assessment. Osteogenesis imperfecta cannot be excluded on the basis of apparently normal bone density or cortical thickness with routine radiographs.

Absorptiometry, Photon↗
PubMed1993

Osteogenesis imperfecta: the distinction from child abuse and the recognition of a variant form.

Unexplained fractures are characteristic of both osteogenesis imperfecta (OI) and non-accidental injury (NAI) but in most cases the diagnosis is straightforward. However, in a few OI patients an initial diagnosis of NAI is made. Factors contributing to such difficulties include failure to recognise that OI can occur without a family history, without blue sclerae, without osteopenia, without an excess of Wormian bones, or with metaphyseal fractures. In addition we report on 39 patients with an unusual history in that fractures only occurred in the first year of life. Rib fractures, metaphyseal abnormalities and periosteal reactions were common. The initial diagnosis was usually OI if the fractures occurred in hospital, but NAI if they appeared to have been sustained at home. Additional findings such as anaemia, vomiting, hepatomegaly, and apnoeic attacks were often found in these patients. The disorder has some similarities to the syndrome of infantile copper deficiency. Like the latter it is particularly common in preterm infants and in twins. Therefore, we are attempting to examine the incidence of significant hypocupraemia in unselected preterm infants. We suggest that the likely cause of this "temporary brittle bone disease" is a temporary deficiency of an enzyme, perhaps a metalloenzyme, involved in the post-translational processing of collagen.

Child Abuse↗