Search PubMed⌕ Search

Biomedical subjects

E Thompson

Publications and source records attributed to E Thompson.

At least 181 records · Page 10Linked to original sources
PubMed1986

Stapled cholecystojejunostomy and gastrojejunostomy for the palliation of unresectable pancreatic carcinoma.

This technique of combined gastrojejunostomy and cholecystojejunostomy utilizing gastrointestinal staplers provides a quick, simple, safe, and effective means for palliation of biliary and duodenal obstruction occurring in patients with unresectable carcinoma of the head of the pancreas. Use of a common loop of jejunum for both biliary and gastric bypass avoids the complexities of other reported methods.

Cholestasis↗
PubMed1986

Evidence against the structural gene encoding type II collagen (COL2A1) as the mutant locus in achondroplasia.

The structure of the locus encoding the major cartilage collagen gene (COL2A1) was studied in a total of 19 cases of achondroplasia. No gross rearrangements were seen. The segregation of COL2A1 was examined in three affected kindreds using restriction site and length variants as genetic markers. In two kindreds discordant segregation between the achondroplasia and COL2A1 loci was demonstrated. Paternity/maternity was confirmed using a 'minisatellite' core sequence probe which reveals cross hybridising polymorphic loci.

Achondroplasia↗
PubMed1986

Central nervous system toxicity following the treatment of pediatric patients with ifosfamide/mesna.

Ifosfamide/mesna treatment of 50 patients with pediatric malignant solid tumors was associated with the development of neurotoxic signs and symptoms in 11 of these individuals who received 29 courses of treatment. Neurologic toxicity included changes in mental status, cerebellar function, cranial nerve, and cerebellar and motor system function, including seizures. All symptoms, signs, and EEG abnormalities were transient. Some of the affected individuals failed to develop acute neurotoxic signs of symptoms when retreated with ifosfamide. A grading system for scoring these neurologic abnormalities is presented for comparison of acute neurotoxic effects of other agents. Recommendations are made regarding early termination or delay of ifosfamide/mesna treatments in the presence of significant neurotoxicity.

Adolescent↗
PubMed1986

DNA repair in nondividing human lymphocytes: inhibition by deoxyadenosine.

Resting peripheral blood lymphocytes have a large number of single strand breaks and are especially sensitive to DNA damaging agents. Deoxyadenosine, an adenosine deaminase substrate, in combination with the adenosine deaminase inhibitor deoxycoformycin, causes accumulation of single strand breaks in resting peripheral blood lymphocytes. The induction of single strand breaks by deoxyadenosine is the result of the accumulation of large amounts of intracellular dATP, which creates imbalance in deoxynucleoside triphosphate levels. This imbalance in deoxynucleoside triphosphate levels interferes with the repair of single strand breaks in deoxyadenosine treated cells. Deoxyadenosine acts synergistically with N-methyl-N'-nitro-N-nitrosoguanidine, a DNA alkylating agent, by inhibiting the repair of N-methyl-N'-nitro-N-nitrosoguanidine-induced single strand breaks. We propose that the increased sensitivity of resting peripheral blood lymphocytes to deoxyadenosine and possibly to other DNA damaging agents may be associated with impaired DNA repair ability due to imbalance in intracellular levels of deoxynucleoside triphosphate.

Coformycin↗
PubMed1985

Characterization of peptides cleaved by plasmin from the C-terminal polymerization domain of human fibrinogen.

The C-terminal region of the fibrinogen gamma chain is known to participate in several functional interactions including fibrin polymerization. This part of the molecule is retained on the gamma chain of fragment D (FgD) when fibrinogen is digested by plasmin in the presence of calcium to produce the fragment D-fragment E (FgD X FgE) complex but is lost if FgD is prepared in the absence of calcium. In an attempt to characterize the C-terminal polymerization domain we have used three techniques to examine this further degradation of FgD following the addition of EDTA and plasmin. Analysis of the digestion by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a progressive cleavage of the gamma chain to two small remnants. The polymerization-inhibitory activity of the whole digest was studied using acid-solubilized fibrin. A progressive loss of inhibitory activity was associated with gamma chain shortening, reaching greater than a 120-fold reduction at the end of digestion. The cleavage of peptides was followed by reverse-phase high performance liquid chromatography and the release of a characteristic peptide triplet was associated with gamma chain cleavage. Manual sequencing, amino acid analysis, and fast atom bombardment mass spectrometry established the three peptides as gamma 303-356, 357-373, and 374-405. These peptides have sequences in common with those peptides recently reported by other investigators to be potent polymerization inhibitors. However, when a mixture of the three peptides was added in a 200-fold molar excess to polymerizing fibrin, no inhibitory activity could be demonstrated. It is concluded that the C-terminal polymerization domain of fibrinogen may be an extended region which includes the sequence gamma 303-405, when this is contiguous with the remainder of the gamma chain.

Amino Acid Sequence↗
PubMed1985

Characterization of mouse lymphoma cells with altered nucleoside transport.

A mutant clone (NT-1) of a T-cell lymphoma was selected for its ability to grow in HAT medium (hypoxanthine, aminopterin and thymidine) in the presence of the nucleoside transport inhibitor P-nitrobenzyl-6-mercaptoinosine (NBMI). NT-1 cells contain half the number of NBMI binding sites present on the parental S49 cells and are partially able to transport nucleosides in the presence of the transport inhibitor (NBMI). These observations suggest that the mutant cells are heterozygous for nucleoside transport proteins and contain two types of transport proteins: the first protein can both bind and is inhibited by NBMI similar to the wild type phenotype, and the second is an altered protein. The altered transport protein apparently lost its NBMI binding sites without a parallel loss of nucleoside transport ability suggesting that the nucleoside transported sites are separate from the binding sites of the transport inhibitor.

Adenosine↗
PubMed1985

Seckel syndrome: an overdiagnosed syndrome.

Five children in whom a diagnosis of Seckel syndrome had previously been made were re-examined in the genetic unit. One child had classical Seckel syndrome, a sib pair had the features of the syndrome with less severe short stature, and in two children the diagnosis was not confirmed. Seckel syndrome is only one of a group of low birth weight microcephalic dwarfism and careful attention should be paid to fulfillment of the major criteria defined by Seckel before the diagnosis is made. There remains a heterogeneous group of low birth weight microcephalic dwarfism yet to be defined.

Adolescent↗
PubMed1985

Phenotypic variation in LADD syndrome.

A mother and son are reported with chronic dacrocystitis, cup shaped ears, hearing loss, abnormal teeth, and poor formation of saliva and tears. They are similar to previously reported cases of lacrimo-auriculo-dento-digital (LADD) syndrome. The variability of expression of this autosomal dominant syndrome is discussed, and it is suggested that poor saliva and tear formation be added to the phenotype.

Deafness↗
PubMed1984

Fast computer search for similar DNA sequences.

An extremely fast method of searching a nucleic acid sequence database against a probe sequence is described. The method is based on the detection of deviation from expected number and deviation from random spatial distribution of sub-sequences which are unique within a sequence, and shared between that sequence and the probe. On an IBM 3081 computer, total search of an encoded form of the EMBL nucleic acid sequence database with a 1 kbase probe sequence is completed in a few seconds. Previous best methods for a similar task required a few minutes.

Animals↗
PubMed1984

Experimental evidence for renal catabolism of fibrin fragment beta 15-42.

The elimination of labelled human fibrin fragment beta 15-42 from the circulation has been studied in an experimental rat model. When 125I beta 15-42 was injected as a bolus into a control group of rats, its elimination from the circulation could be fitted to a two compartment exponential model. A fast initial elimination had a t1/2 of less than 2 min and this was followed by a slower component with a calculated t1/2 of 135 min. The fast component was caused by equilibration of peptide throughout the intra and extra vascular spaces and the slow component reflected the action of catabolic processes once equilibration had been attained. Rats that had undergone bilateral nephrectomy eliminated significantly less of the labelled peptide than the control animals at a given time and the t1/2 of the slow component was prolonged, but not significantly, to 159 min. Rats with ligated ureters had statistically indistinguishable elimination curves from control rats. Examination of the heterogeneity of labelled peptide in plasma samples taken during the experiments by immunoprecipitation and by gel filtration revealed progressive extensive degradation in the control and ureteral ligated rats, but less degradation in nephrectomized rats. These results suggest that beta 15-42 is eliminated, in part, from the circulation by uptake and catabolism by the kidney. It is concluded that impaired renal function may results in elevated plasma levels of beta 15-42 antigen in human renal failure without the need for an increased rate of production of the peptide.

Animals↗
PubMed1984

A diagnostic-prognostic test for bladder cancer using a monoclonal antibody-based enzyme-linked immunoassay for detection of urinary fibrin(ogen) degradation products.

An enzyme-linked immunosorbent assay (ELISA) using a monoclonal antibody was developed to determine the clinical value of urinary fibrinogen/fibrin degradation product levels for the identification and management of patients with bladder cancer. Assays were performed on 286 serial urine specimens from 56 bladder carcinoma patients. Specimens were grouped according to whether the patient had an evident tumor at the time of specimen collection (134 specimens, 41 patients) or was clinically disease-free following treatment (152 specimens, 38 patients). Many patients contributed specimens to both groups as determined by their clinical status at the time of collection. In addition, 45 specimens from 33 patients with inflammation of the urogenital tract and 81 specimens from 19 patients with renal or prostatic cancer were assayed for urinary fibrin degradation products. The ELISA, using a high-sensitivity procedure, identified 83% of the specimens from bladder cancer-positive patients with an overall accuracy with all specimens of 78% and a false-negative rate of 5% for all specimens tested. The high-sensitivity ELISA appeared most appropriate for monitoring bladder cancer patients for recurrence of tumor after surgery. The ELISA using a high-specificity procedure appeared most appropriate for screening. The high-specificity ELISA accurately identified 96% of urine specimens from non-bladder cancer patients with a false-positive rate of only 5%. These results demonstrate that the ELISA is an efficient, reliable, quantitative, and noninvasive immunoassay that can be useful both for the identification of bladder cancer patients and for monitoring the course of the disease.

Aged↗
PubMed1983

Titratable effects of p-chloromercuriphenyl sulfonate, a thiol-attacking reagent, on glucocorticoid receptor binding.

Cytosol prepared from cultured AtT-20 mouse pituitary cells or mouse liver was treated with concentrations of p-chloromercuriphenyl sulfonate (PCMPS) which reduced but did not abolish receptor-binding activity. Scatchard analysis of triamcinolone acetonide binding to the treated cytosol showed that the PCMPS effect was caused by a reduction of binding affinity with little effect on the apparent binding site concentration. The effect on affinity was dose-dependent. Binding specificity appeared unaffected since the relative abilities of triamcinolone acetonide, dexamethasone, cortisol, progesterone, and corticosterone to compete with labeled triamcinolone were similar at various PCMPS concentrations which caused a progressive reduction of detectable cytosol binding. The PCMPS effect was reversible since cytosol treated with up to 200 microM PCMPS followed by dithiothreitol 15 min later showed nearly complete recovery of binding sites (62-100%). The possibility that several sulfhydryl groups were involved in this phenomenon was further explored in experiments using AtT-20 cytosol labeled with [3H]dexamethasone-mesylate, a glucocorticoid affinity label which binds covalently to sulfhydryl groups. Chromatography of dexamethasone-mesylate labeled receptor on a sulfhydryl affinity column resulted in binding, indicating that the receptor had at least two sulfhydryl groups, one bound to the mesylate moiety of the steroid and the other capable of binding to the affinity column.

4-Chloromercuribenzenesulfonate↗
PubMed1983

Hydrocele formation in patients with Hodgkin's disease.

Hydroceles developed in 12 (7.7%) of 155 consecutive male patients who had Hodgkin's disease treated between 1962 and 1981. Except for one patient who had a hydrocele at diagnosis, all developed this complication during remission, 8 months to 7.5 years after inverted-Y or abdominopelvic 60Co irradiation (3000-3800 rad). Hydroceles were bilateral in five patients and on the right side in seven. No tumor was found in the hydrocele sacs of the ten patients who underwent hydrocelectomy. Lymphatic obstruction was evidenced by lymphatic dilation in the hernia sac in six patients. The authors believe postirradiation fibrosis of the lymphatic pathway was the main cause of hydrocele formation.

Adolescent↗
PubMed1983

Delayed release of an abnormal fibrinopeptide A from fibrinogen Manchester: effect of the A alpha 16 Arg leads to His substitution upon fibrin monomer polymerization and the immunological crossreactivity of the peptide.

Fibrinogen Manchester is an abnormal fibrinogen with an impaired release of fibrinopeptide A (FPA) and a polymerization abnormality. In the accompanying article we have identified the amino acid substitution in fibrinogen Manchester as A alpha 16 Arg leads to His. When fibrinogen Manchester was digested with low thrombin concentrations approximately 40-50% of the total FPA content was release at a rate similar to FPA release from normal fibrinogen. The fibrin so formed exhibited an impaired polymerization of monomers. Digestion of fibrinogen Manchester with high concentrations of thrombin for prolonged times released the remaining FPA which had an abnormal retention time when studied by high performance liquid chromatography (HPLC). This fibrinopeptide has been shown previously to contain the A alpha 16 Arg leads to His substitution. fibrin resulting from this exhaustive digestion had normal polymerization of monomers. The normal and substituted FPAs were isolated by HPLC and compared in a double antibody competitive-binding assay for normal FPA. The immunological cross-reactivity of the abnormal peptide was reduced, so that approximately 5 times more abnormal peptide was required on a molar basis to displace labelled normal FPA. Normal intact fibrinogen was 10-fold less reactive (on a half molar basis) than free normal FPA and the crossreactivity of fibrinogen Manchester was measurably less than that of normal fibrinogen. It is concluded that immunological measurement alone of FPA released from abnormal fibrinogens may not give a complete description of the kinetics of peptide release if the amino acid substitution lies within the FPA sequence. The combination of radioimmunoassay and HPLC, however, provides a powerful analytical approach that should be useful in classifying and characterizing abnormal fibrinogens.

Blood Coagulation Disorders↗