Robert L. Baehner
Riley Hospital for Children
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Featured researches published by Robert L. Baehner.
The New England Journal of Medicine | 1976
Laurence A. Boxer; August M. Watanabe; Manfred Rister; Henry R. Besch; John M. Allen; Robert L. Baehner
Because ascorbate potentiates chemotaxis of normal leukocytes, we examined the effect of ascorbate on polymorphonuclear leukocytes from a patient with the Chediak-Higashi syndrome. Chemotactic migration was 104+/-16 leukocytes per 10 fields (mean+/-S.D.) initially and 258+/-44 (P less than 0.001) after ascorbate, as compared to 182+/-10 in controls. There was no bactericidal activity by 40 minutes in the patients untreated leukocytes. After ascorbate bactericidal activity of patient and untreated control cells was the same. The addition of ascorbate reduced cAMP levels in the patients cells from a mean of 34.5 pmoles per 10(7) polymorphonuclear leukocytes to 5.9, as compared to a control value of 3.1+/-1.4. The association of elevated cAMP and impaired function in the polymorphonuclear leukocytes of patients with the Chediak-Higashi syndrome may be related to abnormal microtubular assembly.
Cancer | 1976
Arold J. Altman; Robert L. Baehner
Case reports of 28 neuroblastoma patients who had opso‐myoclonus as their presenting feature are reviewed. As contrasted with the 30%–34% two‐year survival rate for the overall population of patients with neuroblastoma, those who exhibited the opso myoclonus/neuroblastoma combination had a tumor‐free two‐year survival rate of 89.3%. This excellent prognosis may be explained partially by earlier diagnosis and a higher percentage (71% vs. 33%) of patients with Stage I, II, and IV‐S disease in the opso‐myoclonus sub‐group. However, these factors are not, of themselves, sufficient to explain totally the differences in survival rate since five of seven patients with Stage III‐IV disease also exhibited long‐term survival. This raises the question as to whether the neurologic dysfunction in these patients is pathogenetically related to an unknown factor (possibly autoimmune) which also controls growth and spread of the tumor.
Journal of Clinical Investigation | 1980
Laurence A. Boxer; John M. Allen; Robert L. Baehner
To investigate the biochemical and cellular basis for the rise in polymorphonuclear leukocyte (PMN) count during epinephrine administration, PMN from subjects receiving epinephrine were studied for their capacity to adhere to nylon wool fibers and endothelial cell monolayers. After administration of epinephrine, the PMN count increased by 80% at 5 min, and isolated PMN adherence to nylon fibers fell from a base line of 44+/-2-18+/-3%. In contrast, when subjects were infused with the beta-antagonist propanolol before receiving epinephrine, the PMN count failed to rise and PMN adherence was normal. Exposure of PMN endothelial cell monolayers to 0.1 muM epinephrine led to diminished PMN adherence that could be blocked by 10 muM propanolol but not by 10 muM phentolamine. Sera obtained from subjects 5 min after receiving epinephrine or from supernates derived from endothelial cell monolayers exposed to 90 nM epinephrine inhibited PMN adherence to nylon fibers. Addition of anticyclic AMP antisera but not anticyclic guanosine monophosphate antisera to the postepinephrine sera or to the postepinephrine supernate derived from the endothelial cell monolayers abolished their inhibitory effect of PMN adherence to nylon fibers. In contrast, direct exposure of PMN to epinephrine failed to affect their adherent properties. Because it has been previously shown that endothelial cells contain beta-receptors and respond to catecholamines by raising their intracellular concentrations of cyclic AMP, and that PMN adherence is attenuated by cyclic AMP, it would appear that diminished PMN adherence after epinephrine administration is mediated through endothelial cell beta-receptor activity, which in turn impairs PMN margination in vivo and could account for the rise in circulating PMN.
The Journal of Pediatrics | 1980
Robert J. Wells; Robert M. Weetman; Robert L. Baehner
bitors of coagulation in nonhemophiliac children, J PEDIATR 96:439, 1980. 6. Green D: Spontaneous inhibitors of factor VIII, Br J Haematol 15:57, 1978. 7. Klein KG, Parkin JD, and Madaras F: Studies on acquired inhibitors of factor VIII induced by penicillin allergy, Clin Exp Immunol 26:155, 1976. 8. Schleider MA, Nachman RL, Jaffe EA, and Coleman M: A clinical study of the lupus anticoagulant, Blood 48:499, 1976. 9. Feinstein DI, and Rappaport SI: Acquired inhibitors of blood coagulation, Prog Hemost Thromb 1:75, 1972. 10. Kirk PJ, McLellan DS, and Aronstram A: Acquired circulating anticoagulant in a four year old child, Br Med J 2:1296, 1976. 11. Beck DW, Strauss RG, Kisker CT, and Henriksen RA: An intrinsic coagulation pathway inhibitor in a three year old child, Am J Clin Pathol, 71:470, 1979.
Pediatric Research | 1979
Ghazally Ismail; Laurence A. Boxer; Robert L. Baehner
Summary: IgG-coated liposomes containing glucose oxidase (GO) in order to provide a means of generating H2O2 were prepared. Leukocytes from patients with chronic granulomatous disease (CGD) which are lacking a means of generating H2O2, ingested the IgG-coated liposomes and metabolic oxidative deficiencies of glucose-1-14C oxidation and iodination were normalized. Both of these activities have been shown to depend upon the availability of H2O2 within polymorphonuclear leukocytes. Improvement in the capacity to kill Staphylococcus aureus by chronic granulomatous disease leukocytes were observed under similar conditions. Thus, it is possible to restore the oxidative metabolic capacities to CGD leukocytes by the introduction of glucose oxidase containing liposomes to these cells.Speculation: It is possible to restore the oxidative metabolic capacities and to obtain moderate improvement in the bactericidal functions in vitro of CGD leukocytes by providing the cells ingestible liposomes containing GO. Further studies might define more efficient methods for introducing oxidase activity into these cells, or employing drugs that generate H2O2.
Pediatric Research | 1977
Laurence A. Boxer; Susan B Richardso; Robert L. Baehner
An easily performed assay to identify the C3b and Fc receptor on human polymorphonuclear leukocytes (PMN) was developed. Salmonella typhi were directly fluoresceinated and then incubated in non-immune fresh human serum which led to C3b fixation via activation of the alternative pathway. Similarly, Type II pneumococci were fluoresceinated and opsonized with type specific rabbit anti-serum. PMN bearing C3b and Fc receptors formed rosettes with the respective bacteria which were easily readable because of their bright fluorescence. Studies employing various surface agents were employed to provide information on the physical properties of PMN receptors. Incubation of PMN at 37° C with C3-coated bacteria generated 54±5% C3b rosettes whereas PMN incubated with IgG coated bacteria yielded 78±8% rosettes. Heat inactivation of the fresh human serum at 56° C for 30 minutes completely inhibited the formation of the C3b and addition of goat anti-rabbit IgG inhibited the formation of the Fc rosettes. Pre-incubation of PMN with 1 mg/ml Trypsin, 1 mM N-ethyl maleimide, xanthine-xanthine oxidase to generate 20 nm superoxide anion and hydrogen peroxide (H2O2), 10 mM H2O2, and 8×10−4 M hydrocortisone reduced the number of C3b rosettes to values of 25±6%, 7±6%, 22±4%, 36±2%, and 24±5%, respectively, but had no significant effect on the number of Fc rosettes. Thus, this study provides evidence for selective receptors for C3b and Fc on PMN membranes.
Blood | 1981
Rs Oseas; Yang Hh; Robert L. Baehner; Laurence A. Boxer
Blood | 1982
Leah M. Ingraham; Td Coates; John Allen; Coleen Higgins; Robert L. Baehner; Laurence A. Boxer
Journal of Clinical Investigation | 1982
Laurence A. Boxer; Richard A. Haak; H H Yang; J B Wolach; J A Whitcomb; C J Butterick; Robert L. Baehner
Blood | 1977
Laurence A. Boxer; Rister M; John M. Allen; Robert L. Baehner