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Biomedical subjects

D Lee

Publications and source records attributed to D Lee.

At least 577 records · Page 32Linked to original sources
PubMed1982

Influence of morphinization on the development of isoenzymes of pyruvate kinase in rat liver.

1. Acute administration or morphine to foetuses and neonates either directly or via the mother leads to a decrease in the total pyruvate kinase activity. 2. The L-type isoenzyme is selectively suppressed while the M-type isoenzyme is not altered to any significant extent with a consequent lowering of the L/M ratio. 3. The decrease in the total pyruvate kinase activity and the L/M ratio is more prominent when the route of administration of morphine is via the mother. 4. The possible explanation for this difference in the route of administration is that morphine can be converted into a more active metabolite with greater biological potency in adult animals.

Animals↗
PubMed1982

A simplified model for heterotopic rat heart transplantation.

A technique for simplified heterotopic rat heart transplantation having only aorto-aortic anastomosis is presented. The heterotopic rt heart survives and functions well when one lung lobe is attached t the transplantation and functions as a reservoir. Iso- and allotransplants are compared by electrocardiogram (ECG) determination and histological examination. Isotransplants exhibited normal heart and lung throughout the 6-month observation period. allotransplants ceased to function by the 16th postoperative day, with the cessation of palpable heart beat over the abdominal wall by the 10th postoperative day. This simplified heterotopic rat heart transplantation model can be operated by nonsurgeons in an unhurried manner with minimal training in microvascular surgery, and can be applied to various transplantation immunological studies.

Animals↗
PubMed1982

Infiltrating lobular carcinoma of the breast.

On review of the histology of 1050 primary breast carcinomas, 103 cases of infiltrating lobular carcinoma were identified and clinical and survival data collected in each case. The tumours were then separated into four groups on the basis of histological pattern and these groups shown to have significantly different survival times. Assessment of the presence of in situ carcinoma, elastosis and intracytoplasmic lumina was performed in each case and the effect of these features on survival investigated. In addition to stage of disease at presentation, the major significant factor in predicting survival of patients with this type of invasive carcinoma is histological type.

Adult↗
PubMed1982

Development and use of radioimmunoassays for the detection of human IgG antibodies to laboratory animal urinary proteins.

A radioimmunoassay method for the detection of human IgG antibodies to laboratory animal urinary proteins has been developed using partially purified protein fractions prepared from crude urine extracts by gel filtration. The proteins from the four species, mouse, rat, guinea pig and rabbit, were labelled with 125I and used in an antigen binding assay employing a sepharose-linked staphylococcal protein A immunosorbent. Results, expressed as arbitrary units of specific IgG per unit serum, show antibodies to one or more species present in 57% of current animal workers compared with 6% of non-animal workers.

Animals↗
PubMed1982

Clonal expression of the Tn antigen in erythroid and granulocyte colonies and its application to determination of the clonality of the human megakaryocyte colony assay.

To evaluate whether exposure of Tn determinants at the surface of human erythrocytes, platelets, and granulocytes could arise from a somatic mutation in a hemopoietic stem cell, burst-forming unit erythroid (BFU-E) colonies, colony-forming unit granulocyte-macrophage (CFU-GM), and colony-forming unit-eosinophil (CFU-Eo) were grown from a blood group O patient with a typical Tn syndrome displaying two distinct populations (Tn(+) and Tn(-)) of platelets, granulocytes, and erythrocytes. A large number of colonies was observed. Individual colonies were studied with a fluorescent conjugate of Helix pomatia agglutinin (HPA). A sizeable fraction of each of the erythroid and granulocytic colonies appeared to consist exclusively of either HPA-positive or HPA-negative cells, thereby demonstrating the clonal origin of those exhibiting the Tn marker. Similar results were obtained from a second patient. These findings establish that the HPA labeling of Tn cells is an accurate marker permitting assessment of the clonality of the human megakaryocyte (MK) colony assay. For the study of MK cultures a double-staining procedure using the HPA lectin and a monoclonal antiplatelet antibody (J-15) was applied in situ to identify all MK constituting a colony. Our results, obtained in studies of 133 MK colonies, provide definitive evidence that the human MK colony assay is clonal because all MK colonies were exclusively composed of Tn(+) and Tn(-) MK. Furthermore, the distribution of MK within a single colony was shown to be seminormal with a mean at 6 MK, isolated MK typically being absent in culture. Comparison of the proportion of mature Tn(+) cells in blood with their respective Tn(+) progenitors has also shown that no proliferative advantage occurs after the commitment; because Tn polyagglutinability is an acquired disorder, then the expansion of the Tn(+) clone must occur either during the proliferative stage of the pluripotent stem cell or during the commitment itself. This study therefore affords evidence that a blood group antigen plays a role in the differentiation of a pluripotent stem cell.

Adult↗
PubMed1982

alpha 1-Proteinase inhibitor production by human adenocarcinomas xenotransplanted into nude mice.

Human colon adenocarcinomas xenotransplanted into BALB/c nude mice were examined for the ectopic synthesis of alpha 1-proteinase inhibitor(s) (alpha 1Pi). Tumor extracts were prepared by homogenization followed by molecular sieve chromatography on Sepharose 4B. Fractions with immunoreactive alpha 1Pi were concentrated and adsorbed onto a concanavalin A-Sepharose 4B affinity column, then eluted, concentrated, and analyzed. All 4 colon tumors examined produced alpha 1Pi with full antigenic identity to normal human plasma alpha 1Pi. Electrophoretic mobilities of 3 of the tumor-derived alpha 1Pi were different from the electrophoretic mobility of the normal human plasma alpha 1Pi. Activities of the inhibitors were determined by the reaction of each tumor extract with pancreatic elastase (PE) followed by immunoelectrophoresis of the reaction mixture against both anti-human alpha 1Pi and anti-PE antisera. Two of the tumor-derived alpha 1Pi examined were active in inhibiting PE.

Adenocarcinoma↗
PubMed1982

The use of doxapram in the prevention of postoperative pulmonary complications.

A prospective, double-blind, randomized controlled clinical trial has been conducted to assess the effect of doxapram hydrochloride infusions on pulmonary complications in patients undergoing extensive abdominal operations. For the purposes of this study, a pulmonary complication was defined as the production of purulent sputum or the presence of any abnormal clinical or roentgenologic chest signs. Of the 53 control patients, 41 had chest problems develop by these criteria, whereas the same was true of only 20 of the 40 patients receiving doxapram. The average duration of hospitalization was one day less for those receiving the drug.

Clinical Trials as Topic↗
PubMed1981

The management of acute sigmoid volvulus.

One hundred and thirty-four patients with acute sigmoid volvulus are analysed. When the diagnosis is made preoperatively, decompression per rectum is effective in 85 per cent of cases, and should be the initial treatment of choice unless gangrene of the bowel is suspected. In this situation emergency laparotomy should be performed and where gangrenous bowel is confirmed a Hartmann resection appears to be associated with a low mortality and least complications. When the sigmoid loop is found to be viable, it should still be resected. The merits and pitfalls of various procedures in this situation are discussed.

Acute Disease↗
PubMed1981

Volvulus of the transverse colon.

Volvulus of the transverse colon is rare. Seven cases, 6 acute, are presented. Early diagnosis and prompt surgical management prevented complications. At laparatomy, extended right hemicolectomy or end colostomy and distal mucous fistula are the procedures of choice. Non-resection was associated with recurrence in three cases.

Adult↗
PubMed1981

Genetic recombination of bacteriophage T7 in vivo studied by use of a simple physical assay.

A new physical method was developed to assay genetic recombination of phage T7 in vivo. The assay utilized T7 mutants that carry unique restriction sites and was based on the detection of a new restriction fragment generated by recombination. Using this assay, we reexamined the genetic requirements for recombination of T7 DNA. Our results were in total agreement with previous findings in that recombination required the products of genes 3 (endonuclease), 4 (primase), 5 (DNA polymerase), and 6 (exonuclease). Recombination was found to be independent of DNA ligase and DNA packaging and maturation functions.

DNA Primase↗
PubMed1981

Performance evaluation of image-intensifier tubes.

A series of image quality measurements were obtained over a two-year period for eight image-intensifier tube fluoroscopic units used in clinical practice. The measurements were in agreement with a radiologist's opinion of the image quality for each tube. The results showed that some systems did not change significantly over the two-year period, while others deteriorated from acceptable to unacceptable image quality during this time. For this reason, it is recommended that measurements be obtained for all diagnostic fluoroscopic equipment at least semiannually to monitor image quality and remedy any changes before diagnostic accuracy is severely affected.

Fluoroscopy↗
PubMed1981

Secretion of alpha 1-proteinase inhibitor by cultured rat alveolar macrophages.

Alpha 1-proteinase inhibitor, metabolically labeled with 35S, was detected in concentrated culture medium of rat alveolar macrophages by immunoelectrophoresis autoradiography. The metabolically labeled macrophage alpha 1-proteinase inhibitor had the same electrophoretic mobility as did pure rat serum alpha 1-proteinase inhibitor. Moreover, monospecific antiserum to rat serum alpha 1-proteinase inhibitor precipitated a 35S-labeled protein from macrophage culture supernates, and this protein was shown by sodium dodecyl sulfate polyacrylamide gel electrophoresis to have a molecular weight close to that of rat serum alpha 1-proteinase inhibitor. Cycloheximide (an inhibitor of protein synthesis) at a concentration of 0.50 micrograms/ml, inhibited secretion of labeled inhibitor. This, cultured rat alveolar macrophages secrete detectable concentrations of a proteinase inhibitor believed to play a major role in lung defense.

Animals↗
PubMed1981

Psychotic exacerbation with haloperidol.

A case illustrating the worsening of a patient's schizophrenic symptoms following haloperidol dosage increases in presented. This case is remarkable in that few cases of psychotic exacerbation with haloperidol dosage increases have been reported in the world literature. The possibility exists that, like certain tricyclic antidepressants, neuroleptic medication may possess a "therapeutic window,". The concept of a therapeutic window and its relationship to the phenomenon of psychotic exacerbation is reviewed. In evaluating this condition, the clinician should consider other causes of psychotic exacerbation, such as akathisia and anticholinergic psychosis.

Adolescent↗
PubMed1981

Non-uniform swelling properties of the corneal stroma.

The swelling properties of the anterior and posterior stroma of bovine and rabbit corneas were examined by three different methods. The results show that the posterior stroma can swell more than the anterior stroma. Also, at a given swelling pressure, the posterior stroma is more hydrated than the anterior stroma. In a third experiment it is demonstrated that the posterior stroma is also more hydrated in the living eye. It is concluded that the stroma is not a homogeneous structure. The superficial stroma has different physiological properties from the deep stroma. These differences must be taken into account in theoretical models of corneal deturgescence.

Animals↗