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E Dawson

Publications and source records attributed to E Dawson.

At least 55 records · Page 3Linked to original sources
PubMed1994

Genetic mapping of 14 short tandem repeat polymorphisms on human chromosome 22.

We have constructed a linkage map of 14 short tandem repeat polymorphisms (11 with heterozygosity > 70%) on the long arm of human chromosome 22 using 23 non-CEPH pedigrees. Twelve of the markers could be positioned uniquely with a likelihood of at least 1,000:1, and distributed at an average distance of 6.62 cM (range 1.5-16.1 cM). The sex-combined map covers a total of 79.6 cM, the female map 93.2 cM and the male map 64.6 cM. Based on comparisons between physical maps and other genetic maps, we estimate that our map covers 70%-80% of the chromosome. The map integrates markers from previous genetic maps and uniquely positions one marker (D22S307). Data from physical mapping on the location of four genetic markers correlates well with our linkage map, and provides information on an additional marker (D22S315). This map will facilitate high resolution mapping of additional polymorphic loci and disease genes on chromosome 22, and act as a reference for building and verifying physical maps.

Chromosome Mapping↗
PubMed1994

An association study of debrisoquine hydroxylase (CYP2D6) polymorphisms in schizophrenia.

The cytochrome P450 mono-oxygenases are a group of enzymes that metabolize a variety of exogenous and endogenous compounds, some of which are potentially toxic. Individual variations in the metabolism of potential toxins could influence susceptibility to disorders having genetic and environmental components, such as schizophrenia. The frequency of two common mutant alleles of the gene for the cytochrome P450 enzyme debrisoquine-4-hydroxylase (CYP2D6) was determined in 264 Caucasian schizophrenic patients and 217 controls, using the polymerase chain reaction and restriction enzyme digestions. The patient and control samples showed no significant deviation from Hardy-Weinberg equilibrium and the frequency of each mutant allele (CYP2D6A and CYP2D6B) did not differ between patients and controls.

Alleles↗
PubMed1993

A continuous linkage map of 22 short tandem repeat polymorphisms on human chromosome 12.

A continuous linkage map consisting of 22 short tandem repeat polymorphisms has been constructed for human chromosome 12 using 23 non-CEPH pedigrees. The markers were distributed at an average distance of 9.35 cM (3.1-33.9 cM). Eighteen of the markers could be positioned uniquely with a likelihood of > 1000:1. The physical locations of some of the markers suggest that the map covers 85-95% of the chromosome. This framework map of 18 markers has a female length of 213 cM and a male length of 131 cM. Female recombination frequencies were greater than male recombination frequencies except in the distal portion of the short arm. The map provides confirmatory evidence for orders established previously on CEPH pedigrees and uniquely positions 4 additional markers (CD4, ATPSB, D12S56, PLA2).

Chromosome Mapping↗
PubMed1993

The gene for Darier's disease maps to chromosome 12q23-q24.1.

Darier's disease is a rare autosomal dominant skin disorder in which there is abnormal adhesion between keratinocytes. It appears to be associated with an increased prevalence of neuropsychiatric disorders including mental retardation and epilepsy. In addition we have previously reported a family in which major affective disorder cosegregates with Darier's disease. In the present study we have localized the gene for Darier's disease to chromosome 12q23-q24.1 by linkage analysis in five British pedigrees. We obtained a maximum two point lod score of 4.29 with marker D12S84 at zero recombination fraction. All five families showed evidence of linkage between the disease gene and markers in this region. Subsequent identification of the Darier's disease gene will provide insights into normal mechanisms of cell adhesion and may be of importance in the genetic investigation of neuropsychiatric disorders as well as elucidating the pathogenesis of Darier's disease itself.

Chromosome Mapping↗
PubMed1992

Utility of internal markers to improve the accuracy of cystic fibrosis genotype analysis.

DNA diagnostic tests often utilize restriction endonuclease digestion of PCR-amplified portions of genes under analysis. When partial digestion occurs, the resulting patterns may lead to error in diagnosis. To overcome such potential errors in cystic fibrosis testing, we have developed internal markers that can increase the precision and reliability of genotype assignments.

Cystic Fibrosis↗
PubMed1990

A multicenter analysis of percutaneous discectomy.

This study was performed to evaluate a group of patients undergoing percutaneous discectomy. All patients had a single level unilateral L4-5 or L5-S1 disc herniation documented on either computer tomographic (CT) scan, myelogram, and/or magnetic resonance imaging (MRI). Average follow-up after percutaneous discectomy was 16.8 months (range, 2-46 months). The average hospitalization time was 1.7 days (range, 1-5 days). Only 21 patients (55%) were able to return to work after the procedure. Thirteen patients ultimately underwent surgical discectomy for continued symptoms after the procedure. The additional 4 patients did not undergo surgical discectomy and never returned to work. Of those 25 percutaneous discectomy patients who did not undergo surgical discectomy, there was significantly more pain, residual weakness, and numbness compared with the patients undergoing surgical discectomy. The results of this study clearly indicate that percutaneous discectomy does not appear to be as predictable or successful a treatment modality as surgical discectomy.

Adult↗
PubMed1988

Transvaginal ultrasound directed oocyte collection for in vitro fertilization: successes and complications.

From December 1985 to April 1986, 458 patients underwent 600 transvaginal ultrasound-directed oocyte pickups (TVOPU) in preparation for in vitro fertilization and embryo transfer at The Royal North Shore Hospital of Sydney. Collections (552) were performed under light general anesthetic and, more recently, 48 were performed with light sedation. At least one oocyte was collected in 98.7% of all TVOPUs. A total of 3117 follicles (greater than 12 mm) were aspirated and 2576 oocytes were collected. Ninety-two clinical pregnancies were established after embryo transfer in 474 cycles. Major operative morbidity was low, with three pelvic abscesses and three pelvic hematomas reported. The procedure was well accepted by patients, with only one expressing a preference for the laparoscopic method. TVOPU is now the preferred method of oocyte pickup in our unit.

Embryo Transfer↗
PubMed1986

The effect of labetalol on urinary prostacyclin secretion during surgery.

The effects of labetalol on the secretion of prostacyclin and plasma-renin activity (PRA) were evaluated, relative to a control group in 24 patients undergoing hip osteotomy. They were randomly assigned to two groups (G-I and G-II) with 12 patients each. Patients allocated to both groups received standard anaesthesia (thiopentone, pancuronium, fentanyl and nitrous oxide). Patients belonging to Group II were given labetalol at a dose of 0.8 mg kg-1. The stable metabolite of PGI2, 6-keto-PGF1 alpha was quantified from urine samples by radioimmunoassay (RIA). Cortisol, PRA and aldosterone were determined from blood samples. A significant increase in 6-keto-PGF1 alpha elimination was observed in G-I. Labetalol administration partially but significantly inhibited this increase. We believe that prostacyclin is involved not through the beta 1 but through the alpha 1 receptors in the secretion of renin.

6-Ketoprostaglandin F1 alpha↗
PubMed1986

The Chiari osteotomy. A review of 58 cases.

Fifty-eight Chiari osteotomies performed in 51 patients were reviewed retrospectively. The indications for surgery were painful subluxation, instability, or poor acetabular coverage. The average age at surgery was 16 years (range, 7-45), and the average follow-up period was 40 months. The majority of the patients had congenital hip dislocation, but also included were patients with cerebral palsy, Legg-Calvé-Perthes disease, polio, infection, coxa vara, and epiphyseal dysplasia. Supplemental bone grafts were applied as needed. The functional results were unrelated to age, with 26 excellent, 28 good, and four poorly functional hips. After operation, 39 out of 41 had total pain relief, 41 out of 58 had a normal acetabular index, and 54 out of 58 had a normal center-edge angle. Trendelenburg gaits were unchanged by the Chiari osteotomy, but trochanteric transfer improved the gait in few cases.

Acetabulum↗
PubMed1985

Do vitamin D supplements improve the physical capabilities of elderly hospital patients?

A randomized double-blind controlled trial of the effect of vitamin D supplementation on the abilities of elderly hospital patients to carry out basic activities of daily life is described. Those patients included in the trial had plasma 25-hydroxyvitamin D concentrations which were low or low normal as judged by the normal range in young adults. After 2 to 9 months on the trial there was no significant difference in the performance of the control and treatment groups.

Activities of Daily Living↗
PubMed1985

The effects of epidural analgesia and conventional anaesthesia on renal excretion of PGE2 during orthopaedic surgery.

The effect of standard anaesthesia (G-I) and epidural analgesia (G-II) on urinary synthesis of PGE2 was compared in two groups of 12 patients each undergoing orthopaedic surgery. This study demonstrates a significant elevation of renal PGE2 in patients undergoing standard anaesthesia during surgery. In marked contrast, with epidural analgesia, the inhibition of renal secretion of PGE2 is apparent. These findings strongly suggest the important role of the sympathetic nervous system in the synthesis of PGE2.

Adult↗
PubMed1984

Intraoperative evoked potential monitoring of the spinal cord: enhanced stability of cortical recordings.

Intraoperative EP monitoring of spinal cord function depends upon a quickly obtained, reproducible EP. The records must be obtained in a hostile environment where artifacts and other sources of electrical noise cannot easily be eliminated: records are obtained continuously without interrupting the surgery. We studied EP reproducibility by measuring cortical EP amplitude range and latency range within individual patients. Reproducibility was enhanced by several changes in the stimulus and recording parameters: (1) Bipolar recording near the vertex (Cz-Pz, E1-E2) eliminated a significant amount of the artifacts and random variations seen in referential recordings. Bipolar recordings sacrifice some amplitude but the improved reproducibility is worthwhile. (2) Restricted filters (especially 30-3000 Hz) improve reproducibility still further, compared to the traditional open filters (1-1000 Hz). (3) Fast stimulation rates improve monitoring up to rates of about 5 stimuli/sec. At even faster rates too much amplitude attenuation usually occurs. Using these techniques stable intraoperative EPs were recorded from all 115 patients except those in whom EPs were abnormal even before surgery. Advantages and disadvantages compared to epidural recording techniques were discussed. Several further observations were made, including (1) monitoring could be done equally as well with stimulation either at the peroneal or at the posterior tibial nerve; (2) balanced nitrous oxide and narcotic anesthesia did attenuate EPs by about 60%, although this is not so much as to interfere seriously with monitoring.

Adolescent↗
PubMed1984

Mary Martha.

Explore the source record for details and available documents.

Canada↗
PubMed1984

Congenital paraxial hemicorpectomy. A case report.

Although physicians may be familiar with terms such as "fibular paraxial hemiamelia," they often do not realize that the defects may involve more proximal levels than are first apparent. The following case report demonstrates a paraxial defect that begins at the level of T2 and extends the remainder of the body. No previous case has been reported, and because of the peculiar distribution of the anomaly, the situation has been termed "congenital paraxial hemicorpectomy."

Abnormalities, Multiple↗
PubMed1983

Toxic effects of propylthiouracil in the rat.

Repeated intraperitoneal administration of propylthiouracil (PTU, 0.5-1.5 mmole/Kg) to rats caused a dose related decrease in body weight. A dose dependent increase in liver weight and a decrease in spleen weight were also seen. Leukocyte counts were markedly reduced in all PTU treated animals. Histopathological changes were observed. These consisted of congestion of red pulp of the spleen and vacuolization of the liver.

Animals↗