Biomedical subjects
M Foster
Publications and source records attributed to M Foster.
Measles serology in children with a history of measles in early life.
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Exercise-induced anaphylaxis as a manifestation of cholinergic urticaria.
Two patients presented with a history of exercise-induced hypotension associated with severe pruritus and either generalized urticaria or facial angioedema. Each patient was exercised under controlled conditions with use of bicycle ergometer exerciser (900 KPM/min) for 20 to 30 min at 23 degrees C. Each patients complained of generalized pruritus and then erupted in lesions typical of cholinergic urticaria. In one patient the lesions became confluent about the face and were followed by eyelid edema, lip swelling, and transient hypotension. Plasma histamine levels were elevated in each patient and reached a maximal level between 20 and 25 min. Neither patient had a change in forced expiratory volume in one second during the episode and detailed pulmonary function testing in one patient revealed no change in airway resistance, specific conductance, forced expiratory vital capacity, or forced expiratory flow rates. One patient had a positive methacholine chloride (Mecholyl) skin test with satellite lesions, and the second patient was skin-test negative. The skin test-positive patient, who was not hypotensive when initially challenged, was strenuously exercised for 15 min/day. Progressively less severe reactions were seen associated with diminished histamine release, and the patient is now on a daily exercise program; symptoms in the second patient are controlled with hydroxazine. Our results indicate that some patients with the exercise-induced anaphylactic syndrome are unusual examples of severe cholinergic urticaria. Furthermore, the utility of a regular exercise program as part of the management of some patients with cholinergic urticaria requires further investigation.
Autoclaves and the sterile supply manager.
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Electron spin resonance studies on caeruloplasmin and iron transferrin in patients with chronic lymphocytic leukaemia.
Whole-blood caeruloplasmin measured by electron spin resonance was studied in 41 patients with chronic lymphocytic leukaemia. The levels were above normal at all stages of the disease, rose with increasing clinical involvement, and were higher in progressive than inactive disease. Whole-blood iron transferrin levels were more variable, and were significantly raised only in patients with marrow failure.
Imaging by nuclear magnetic resonance and its bio-medical implications.
The distribution of proton spin concentration (water concentration) and the proton spin-lattice relaxation time (T1) can be imaged in a sample by placing it in a magnetic field gradient, applying appropriate radio-frequency (rf) pulses, and measuring the rf radiated from the sample. The Aberdeen machine is designed to image the human body in vivo at 400 gauss and 1.7 MHz. The spatial resolution predicted is about 1 cm for a 20% difference of T1. Measurements of T1 for small samples of tissue in vitro show a five-fold range of values for some soft tissues. Breast tumours and liver metastases have shown T1 values very different from the surrounding tissue. The method has the potential of perhaps imaging any pathology which changes water concentration, forms fluid pools or affects the binding of water to macromolecules. The potential hazards, which need more investigation, seem slight.
Decreased hybrid susceptibility to murine myeloma grafts.
The behavior of BALB/c myeloma transplants in (C57BL/10 X BALB/c)F1 hybrids was investigated. The F1 hybrids were less susceptible to the grafts than were the parental BALB/c hosts. Host susceptibility was X-ray and cyclophosphamide sensitive, but an immune hypothesis was not favored since no memory was demonstrable. Males were less susceptible than females, and rabbit antithymus serum had no effect on susceptibility.
Genetics of F1 hybrid susceptibility to myeloma grafts.
The genetics of hybrid susceptibility of parental myeloma transplants in histocompatible F1 hybrids was investigated. Various inbred mouse strains and their descendant congenic lines were crossed with BALB/C mice to produce appropriate F1 hybrids. Genetic inferences were drawn from the comparison of the frequencies of tumor graft takes among congenic combinations. Hybrids containing the C57BL/10 genetic background were less susceptible to myeloma transplants than were hybrids of other genotypes. Both H-2-associated and non-H-2-associated genetic factors played significant roles in determining host susceptibility to the transplants. The D end of the major histocompatibility complex did not play a predominant role in determining hybrid susceptibility in C57BL-derived F1 hybrids.
Macrophages in experimental and human brain tumors. Part 1: Studies of the macrophage content of experimental rat brain tumors of varying immunogenicity.
Although the presence of lymphoreticular cells within tumors has been recognized for over 100 years, it is only within the last decade that the concept has arisen that standard histological examination techniques may lead to an underestimation of the true extent of tumor infiltration by lymphoreticular cells, and particularly by macrophages. The macrophage content of certain systemic tumors has been correlated with their immunogenicity and growth characteristics. Since the central nervous system is to some extent an "immunologically privileged site" and contains within it specialized reticuloendothelial cells called microglia, the authors determined the macrophage content of three rodent brain-tumor cell lines, and attempted to correlate this macrophage content with their immunogenicity and growth characteristics. Their findings indicate a direct correlation between the immunogenicity and macrophage content of these three neural tumor cell lines.
Macrophages in experimental and human brain tumors. Part 2: studies of the macrophage content of human brain tumors.
The authors have analyzed 47 tumors of the central nervous system (11 glioblastomas, nine meningiomas, three medulloblastomas, 12 assorted primary neural tumors, and 12 brain metastases) for their content of macrophages. Cell suspensions were prepared by enzymatic digestion and macrophages were quantitated by IgGEAC rosette formation. Adsorption of sensitized indicator cells (EA) to sections of tumor was used as a measure to determine the distribution of IgGFc receptor-positive cells within the tumors and to serve as a control for selective release of IgGFc receptor-positive cells by enzyme digestion. The 11 glioblastomas had a mean macrophage content of 45% (range: 8% to 78%), the nine meningiomas had a mean of 44% (range: 5% to 81%), the three medulloblastomas a mean of 6% (range 2% to 15%), and the metastatic tumors a mean of 24% (range: 4% to 70%). Adsorption of EA demonstrated that IgGFc receptor-positive cells were distributed throughout the tumor mass, although different types of patterns were observed. There was an excellent correlation between the percent of IgGEAC positive cells in suspensions and the extent of EA adsorption to the tumor sections. Compared to systemic neoplasms, most nervous system tumors have a high macrophage content. It is possible that the high macrophage content of brain tumors is related to their immunogenicity, and may be a partial explanation for tha rarity of brain-tumor metastases.
Low-dose insulin infusions in diabetic patients with high insulin requirements.
Six patients with high insulin requirements (range 120-3000 units daily) have been infused with much smaller doses (range 50-63 units daily) of insulin intravenously. All six maintained adequate glucose homoestasis on this regimen. It is suggested that subcutaneous tissue at the site of injection may alter insulin or impair its absorption. Insulin resistance in some patients may be due to these mechanisms.
Electron spin resonance as a useful technique in the management of Hodgkin's disease.
Electron spin resonance spectroscopy has proved a useful and simple technique for the measurement of levels of caeruloplasmin and iron transferrin in whole blood from 50 patients with Hodgkin's disease. Those patients with clinically active disease show higher caeruloplasmin levels and lower iron transferrin levels than those with inactive disease. The results indicate that these tests are good indicators of the state of the disease and that serial measurement of these parameters may help in early prediction of clinical reactivity and in monitoring response to treatment. The combined information from iron transferrin and caeruloplasmin levels appears to be more predictive than that from the erythrocyte sedimentation rate and neutrophil alkaline phosphatase score.
Electron spin resonance measurements of blood caeruloplasmin and iron transferrin levels in patients with non-Hodgkin's lymphoma.
Caeruloplasmin and iron transferrin level were measured in blood of patients with non-Hodgkin's lymphoma in different stages of disease activity and compared with erythrocyte sedimentation rate and NAP level in the same samples. It was found that both caeruloplasmin level and sedimentation rate showed a slight increase in mean level in patients with active disease as compared with those in remission, particularly in the group of patients with poorly or undifferentiated diffuse disease. No difference was observed in levels of iron transferrin or NAP. Both caeruloplasmin and sedimentation rate showed occasional abnormal values in patients in remission but in most cases where both were elevated the patients subsequently entered a more active phase of the disease.
Letter: The dentist and prevention of infective endocarditis.
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Identification of essential arginyl residues in cytoplasmic malate dehydrogenase with butanedione.
The inactivation of cytoplasmic malate dehydrogenase (L-malate: NAD+ oxidoreductase, EC 1.1.1.37) from porcine heart and the specific modification of arginyl residues have been found to occur when the enzyme is inhibited with the reagent butanedione in sodium borate buffer. The inactivation of the enzyme was found to follow pseudo-first order kinetics. This loss of enzymatic activity was concomitant with the modification of 4 arginyl residues per molecule of enzyme. All 4 residues could be made inaccessible to modification when a malate dehydrogenase-NADH-hydroxymalonate ternary complex was formed. Only 2 of the residues were protected by NADH alone and appear to be essential. Studies of the butanedione inactivation in sodium phosphate buffer and of reactivation of enzymatic activity, upon the removal of excess butanedione and borate, support the role of borate ion stabilization in the inactivation mechanism previously reported by Riordan (Riordan, J.F. (1970) Fed. Proc. 29, Abstr. 462; Riordan, J.F. (1973) Biochemistry 12, 3915-3923). Protection from inactivation was also provided by the competitive inhibitor AMP, while nicotinamide exhibited no effect. Such results suggest that the AMP moiety of the NADH molecule is of major importance in the ability of NADH to protect the enzyme. When fluorescence titrations were used to monitor the ability of cytoplasmic malate dehydrogenase to form a binary complex with NADH and to form a ternary complex with NADH and hydroxymalonate, only the formation of ternary complex seemed to be effected by arginine modification.
The amino acid sequence of a peptide containing the active center histidine residue of porcine malate dehydrogenase-a correction.
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Lipoic acid inhibition of mitochondrial malate dehydrogenase.
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