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E Thompson

Publications and source records attributed to E Thompson.

At least 163 records · Page 9Linked to original sources
PubMed1988

A method for repair of aortic dissection originating in the transverse arch using two sutureless intraluminal prostheses.

We present a method for repair of ascending aortic dissections that originate in the transverse aortic arch. The technique utilizes two sutureless intraluminal prostheses, which are joined together and inserted during hypothermic circulatory arrest. A diamond-shaped opening between the two grafts is anastomosed about the orifices of the brachiocephalic arteries. This method affords the advantage of excluding the intimal tear, thereby preventing further propagation of the dissection. Additionally, the method offers the time-saving advantage of the sutureless prosthetic rings for the proximal and distal anastomoses.

Aortic Dissection↗
PubMed1988

Homozygous osteogenesis imperfecta unlinked to collagen I genes.

In a consanguineous pedigree in which a severe type of osteogenesis imperfecta was segregating as an autosomal recessive trait, analysis of genetic markers for both collagen I structural loci COL1A1 and COL1A2 showed that the phenotype was unlinked to either locus.

Collagen↗
PubMed1988

Relationship between ex vivo anti-proteinase (factor Xa and thrombin) assays and in vivo anticoagulant effect of very low molecular weight heparin, CY222.

There is uncertainty as to which activities of unfractionated heparin (UFH) and low MW heparin are responsible for their anticoagulant and antithrombotic properties. We have sought to answer this question by examining plasma samples taken during a recently conducted dose-finding study of the low MW heparin, CY222, in haemodialysis for chronic renal failure. In this study, in vivo anticoagulant effect was assessed by measurement of plasma FPA levels. UFH was administered as a dose of 5000 iu bolus + 1,500 iu/h maintenance infusion, while the effects of three doses of CY222 were studied (10,000, 15,000 and 20,000 Institute Choay anti-factor Xa u bolus, all with 1,500 Institute Choay anti-factor Xa u/h maintenance infusion). Anti-factor Xa levels were determined by chromogenic substrate assay. Anti-thrombin levels were determined by chromogenic substrate assay and by quantitation of catalysed thrombin-inhibitor complexes (using autoradiography). Analysis of the results indicate that plasma fibrinopeptide A (FPA) levels correlate with anti-factor Xa (r = -0.45) and anti-thrombin (substrate) (r = -0.63) levels of UFH, but only with the anti-factor Xa levels (r = -0.41) of CY222. These results suggest that the anti-factor Xa assay is currently the most suitable assay for monitoring low MW heparins such as CY222 in humans.

Anticoagulants↗
PubMed1988

Dysmorphic syndromes with demonstrable biochemical abnormalities.

Many inborn errors of metabolism are associated with dysmorphic manifestations. In this review, we have attempted to correlate the dysmorphic features with the underlying metabolic defect or its consequences. Most of the defects which we have discussed affect the synthesis or degradation of macromolecules (for example, collagen, elastin, bone mineral, proteoglycans, glycoproteins, and triglycerides). Such defects may affect either a single enzyme or multiple enzymes in specific organelles, such as lysosomes or peroxisomes, or they may affect hormonal control of synthesis and degradation. Examples are also included of defects affecting the catabolism of simple molecules when accumulating metabolites have a secondary effect on macromolecules, as in homocystinuria. In a number of instances, however, the correlation between the biochemical abnormality and the dysmorphic features are not understood. Ultimately, all dysmorphic syndromes will be attributable to a biochemical defect or its effects. The aim of this overview is to provide an insight into the relationship between the two at the present time.

Congenital Abnormalities↗
PubMed1988

Nonoperative management of blunt hepatic trauma in adults.

Although well accepted in pediatric patients, nonoperative management of blunt hepatic trauma in adults remains controversial. From January 1981 through May 1987, 66 adults were identified with blunt hepatic trauma that had been confirmed by abdominal exploration or abdominal computed tomography (CT): 46 underwent immediate operation, and 20 were initially managed nonoperatively. Patients were considered for nonoperative management only if they were hemodynamically stable and had no significant peritoneal irritation. CT criteria for nonoperative management included contained subcapsular or intrahepatic hematoma, unilobar fracture, absence of devitalized liver, minimal intraperitoneal blood, and absence of other significant intra-abdominal organ injuries. The predominant CT pattern in the 17 patients successfully managed nonoperatively included unilobar right-lobe fracture or intrahepatic hematoma. A small amount of blood in either gutter or in the pelvis did not portend failure of nonoperative management. No delayed complications were noted during an average follow-up of 27 months. Nonoperative management of blunt hepatic injury based on abdominal CT findings is a useful alternative in a select group of hemodynamically stable patients.

Accidents, Traffic↗
PubMed1987

Antithrombin III Glasgow: a variant with increased heparin affinity and reduced ability to inactivate thrombin, associated with familial thrombosis.

A functional antithrombin III (AT III) deficiency has been identified in two generations of a family with a high incidence of thrombosis. The deficiency presented as approximately 50% reduction in heparin cofactor activity compared to its antigen concentration. No abnormality was detected by crossed immunoelectrophoresis in the presence or absence of heparin. Plasma from the propositus was precipitated with dextran sulphate, applied to heparin-Sepharose and the AT III stepwise eluted with NaCl. The AT III had a reduced ability to inactivate thrombin, when this was monitored by substrate hydrolysis or by SDS polyacrylamide gel electrophoresis. Its mobility was normal by the latter technique using 10-20% gradient gels under reducing and non-reducing conditions. AT III from the patient was reapplied to heparin-Sepharose and eluted with a NaCl gradient. An active pool eluted in the same NaCl concentration range used to purify normal AT III, while predominantly inactive AT III eluted at higher NaCl concentrations. It is concluded that this variant, designated AT III Glasgow, has increased affinity for heparin but reduced ability to inactivate thrombin.

Antithrombin III↗
PubMed1987

Antithrombin III Northwick Park: demonstration of an inactive high MW complex with increased affinity for heparin.

It has been shown previously that antithrombin III Northwick Park has reduced ability to inactivate thrombin and is characterized by an additional anodal component on crossed immunoelectrophoresis (Howarth et al, 1985). We have applied plasma from an affected family member to heparin-Sepharose and eluted the antithrombin III with a salt gradient. Evidence is presented that a variant component has slightly higher affinity for heparin than normal antithrombin III. Furthermore, this variant component is present in plasma as an approximately 120,000 MW inactive antithrombin III complex that can be reduced with dithiothreitol to MW approximately 60,000, indicating disulphide bridging. Using ion-exchange chromatography, the inactive complex has been isolated and shown to migrate in the same position as the anodal peak on crossed immunoelectrophoresis.

Antithrombin III↗
PubMed1987

Direct analysis of plasma fibrinogen-derived fibrinopeptides by high-performance liquid chromatography: investigation of nine congenital fibrinogen abnormalities.

A simple method has been developed for the rapid analysis of fibrinopeptides contained on fibrinogen in small anticoagulated plasma samples. Following incubation with thrombin the plasma is diluted, boiled and then studied by high performance liquid chromatography (HPLC). The three forms of FPA (AP, A, AY) and two forms of FPB (B, des Arg B) can be identified and quantified in samples of less than 200 microliters. Additionally, the FPB peak height can be used to measure the plasma fibrinogen level. This method has been used to screen plasma samples with abnormal clotting times for possible congenital fibrinogen abnormalities. Results of the study of nine unrelated cases are presented. Four cases of congenital dysfibrinogenaemia were diagnosed directly from HPLC analysis alone. Fibrinogen Sheffield and Paris VI were identified as A alpha Arg 16----His substitutions and fibrinogens London VI and Madrid II were found to be heterozygous for an unknown substitution preventing thrombin cleavage at A alpha Arg 16. A case of dysfibrinogenaemia (fibrinogen Ashford) with a normal fibrinopeptide release stoichiometry was confirmed to have a primary polymerization abnormality using purified fibrin monomers. Similarly, a case of hypodysfibrinogenaemia (fibrinogen London V) had normal fibrinopeptides and a fibrin polymerization abnormality. In one case of hypofibrinogenaemia and two cases of afibrinogenaemia, no fibrinopeptide or functional abnormalities could be definitely established. This rapid and simple method of fibrinopeptide analysis is recommended for screening of plasma samples taken from patients suspected of having abnormalities of fibrinogen synthesis.

Blood Coagulation Disorders↗
PubMed1987

Phagocytosis of erythrocytes sensitized with known amounts of IgG1 and IgG3 anti-Rh antibodies.

Phagocytosis was investigated using human peripheral monocytes and erythrocytes sensitized with known amounts of subclass-specific IgG anti-Rh antibodies. The erythrocyte-bound IgG was quantitated by a radiometric antiglobulin test. This evaluation revealed the following: (1) there is a relationship between phagocytosis and the number of erythrocyte-bound IgG molecules; (2) phagocytosis is IgG subclass-dependent, since a similar degree of phagocytosis is observed with fewer IgG3 than IgG1 molecules and also the minimum number of IgG3 molecules for phagocytosis is 150-640, whilst for IgG1 the minimum is 1,230-4,020; (3) the minimum levels of sensitization for phagocytosis should be detectable by the serological antiglobulin test; (4) the phagocytosis assay is no more sensitive than the monocyte rosette assay for the detection of anti-Rh alloantibodies, and (5) phagocytosis of adherent erythrocytes observed by video-enhanced microscopy indicated that erythrocytes may adhere to monocytes for a considerable time before phagocytosis, but that phagocytosis itself was rapid.

Erythrocytes↗
PubMed1987

The need to screen all retinoblastoma patients for esterase D activity: detection of submicroscopic chromosome deletions.

Roughly 5% of all patients with retinoblastoma carry a constitutional chromosome deletion on the long arm of chromosome 13, which confers a prezygotic predisposition to tumour development. As offspring of deletion carriers have a 50% risk of inheriting the predisposition locus it is important to identify deletion carriers. The site of the esterase D gene to the often deleted region offers an objective means of deletion identification. The chromosomes of a patient with unilateral retinoblastoma, previously supposed to have a normal karyotype, were reexamined after the discovery that his red blood cells contained reduced activities of esterase D. A small sub-band deletion was found in chromosome region 13q14. These findings emphasise the importance of measurements of esterase D in all patients with retinoblastoma, even those with an apparently normal karyotype.

Carboxylesterase↗
PubMed1987

FG syndrome.

Explore the source record for details and available documents.

Abnormalities, Multiple↗
PubMed1987

Deep-freezing versus 4 degrees preservation of avascular osteocartilaginous shell allografts in rats.

Osteocartilaginous allografts (distal femurs of rats) were stored at 4 degrees for six, 12, 24, and 48 hours and at -80 degrees for five days and then evaluated for viability of the bone and cartilage. Storage at 4 degrees for 12 or 24 hours had little effect on cartilage viability but decreased bone viability to 40% and 10% of controls, respectively. Storage at -80 degrees for five days resulted in nonviable bone in all cases but showed an either/or response of cartilage, with high viability in two cases and nonviability in the other eight cases. In a second set of experiments, femurs from rats were stored in situ at 4 degrees for 12 or 24 hours or were harvested and stored at -80 degrees for five days, after which they were transplanted into rats of a different strain. The antibody response to each set of femurs was measured at two, six, and 12 weeks after operation. The 4 degrees storage resulted in a moderately decreased immunogenicity, whereas the storage at -80 degrees resulted in significantly reduced immunogenicity.

Animals↗
PubMed1986

Direct analysis of plasma fibrinogen-derived fibrinopeptides by high performance liquid chromatography: investigation of A alpha-chain N-terminal heterogeneity.

Fibrinopeptide A (FPA), released from the fibrinogen A alpha-chain by thrombin, can be resolved by high-performance liquid chromatography (HPLC) into three forms, the intact peptide (A), a modified peptide phosphorylated at the serine in position 3 (AP), and an N-terminally degraded form (AY). A new method has been developed, using HPLC, that allows direct measurement of the proportions of AP, A, and AY released by thrombin from fibrinogen in plasma samples of 200 ul or less. The method was used to examine variations in the proportions of AP and AY expressed as a % of total FPA in a number of patient and control groups. The mean percentages of AP and AY of plasma fibrinogen were found to be 21.7 and 14.2%, respectively, in normal laboratory controls. In older, apparently normal, individuals these figures were 27.0 and 15.5%, respectively. Cord plasma exhibited very high AP and slightly reduced AY levels (41.6 and 12.4%, respectively) compared with normal adults. Patients with liver failure had low AP levels and high AY levels (11.6 and 21.1%, respectively). Patients recovering from major surgery or acute thrombotic stroke showed an acute-phase rise in fibrinogen level that was accompanied by an increase in AP and variable reduction in AY. Incubation of heparinized whole blood for 8 days in vitro demonstrated a gradual decrease in the proportion of AP and increase in AY of plasma fibrinogen. These results provide some support for the idea that an increased "aging" of fibrinogen in the circulation may result in a decrease in the AP content of fibrinogen accompanied by a more variable increase in AY.

Aged↗
PubMed1986

Direct analysis of plasma fibrinogen-derived fibrinopeptides by high-performance liquid chromatography.

The fibrinopeptides released from fibrinogen by thrombin can be conveniently quantitated by high-performance liquid chromatography (HPLC). This work describes a method that enables direct analysis of fibrinopeptides derived from fibrinogen contained in small amounts of plasma or whole blood without the necessity of fibrinogen purification. Aliquots of plasma or whole blood were treated with thrombin, diluted in buffer at pH 6.0, boiled and centrifuged. After filtration to 0.22 micron the supernatant was analysed directly by HPLC using a 3 microns C18 analytical column fitted with a pre-column. All the known normal fibrinopeptide peaks and their degradation products were clearly resolved from other plasma-derived peptides and the release pattern was identical to that observed with purified fibrinogen. Some samples contained interfering endogenous peptides which were removed by rapid gel-filtration of 200 microliters of plasma before thrombin treatment. The method was quantitative and the peak heights of fibrinopeptide B (FPB) could be used to accurately measure plasma fibrinogen concentrations directly in samples equivalent to 20 microliters of plasma. These fibrin determinations were unaffected by the type of anticoagulant used were performed on blood samples of both human and animal origin collected and/or stored under a variety of conditions. Variations of the method were specifically developed for different applications requiring quantitative fibrinopeptide analysis.

Animals↗
PubMed1986

An autosomal recessive mental retardation syndrome with hepatic fibrosis and renal cysts.

Two sisters had developmental retardation and congenital hepatic fibrosis. One, 23 years old, had facial anomalies reminiscent of Smith-Lemli-Opitz syndrome, ocular coloboma, and hypoplastic kidneys with a single cyst. The other sister died at 18 months and had an encephalocele and cystically dilated collecting ducts in the renal medulla. Although the manifestations in these two sisters are similar to the Smith-Lemli-Opitz and Meckel syndromes respectively, there are sufficient differences to suggest that they had a separate autosomal recessive MCA-MR syndrome.

Adolescent↗