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A C Allison

Publications and source records attributed to A C Allison.

353 records · Page 20Linked to original sources
PubMedDate not supplied

Oxygen consumption by stimulated human neutrophils.

Oxygen consumption by stimulated human neutrophils has been studied. An initial lag after stimulation of about 20 s is followed by a linear phase of oxygen consumption which lasts about 60 s and then declines exponentially. The duration of the respiratory burst is thus much shorter than has been generally recognized. The cessation of the linear phase of oxygen consumption occurs at a constant time after stimulation, is not due to depletion of the substrate of the oxidase enzyme (since linear oxygen consumption can be re-initiated), and is due to termination or saturation of particle uptake. The curtailment of oxygen consumption probably marks the end of the oxygen-dependent microbial role of the phagocytic vacuole, preparing it for the secondary and independent function of digestion. A novel cytochrome b becomes associated with the phagosomes and probably forms a component of a complex electron-transport chain. Superoxide may be an intermediate in this system, but it is unlikely to be released free from the cell or to form the final product of the system.

Granulomatous Disease, Chronic↗
PubMedDate not supplied

Zymosan-induced arthritis: a model of chronic proliferative arthritis following activation of the alternative pathway of complement.

Zymosan particles, which are able to activate complement by the alternative pathway and to induce enzyme secretion from macrophages, were injected into knee joints of mice. After various time intervals, synovia were assessed histologically for various markers of inflammation. Within 7 days after intraarticular injection of zymosan, a chronic inflammatory arthritis with mononuclear cell infiltration, synovial hypertrophy and pannus formation was observed. Latex particles, which do not activate complement or macrophages, produced only mild, transient inflammatory reactions.

Animals↗
PubMedDate not supplied

Amniotic fluid interleukin-6 determinations are of diagnostic and prognostic value in preterm labor.

PROBLEM: The purpose of this study was to determine if amniotic fluid concentrations of the interleukin-6 (IL-6) are of value in diagnosis of microbial invasion of the amniotic cavity and in the prediction of failure of tocolysis, preterm delivery and perinatal morbidity and mortality. METHOD: Amniotic fluid was obtained by transabdominal amniocentesis from 146 consecutive patients admitted with the diagnosis of preterm labor and intact membranes. Fluid was cultured for aerobic and anaerobic bacteria as well as for mycoplasmas. Amniotic fluid IL-6 levels were measured using a monoclonal antibody-based enzyme-linked immunosorbent assay with a sensitivity of 0.03 ng/ml. Logistic regression and Cox's proportional hazards model were used to examine the effect of several variables on dichotomous outcomes or interval to delivery. RESULTS: Patients with a positive amniotic fluid culture had a significantly higher amniotic fluid IL-6 concentrations than patients with a negative culture (median 91.2 ng/ml, range 0.9 to 437 ng/ml versus median 0.4 ng/ml, range < 0.3 to 195 ng/ml, respectively; P < .0001). An amniotic fluid IL-6 concentration of greater than or equal to 11.3 ng/ml had a sensitivity of 93.3% (14 of 15) and a specificity of 91.6% (120 of 131). All patients with an amniotic fluid IL-6 concentration above 11.3 ng/ml and a negative amniotic fluid culture (N = 11) delivered preterm and all placenta available for examination (N = 7) had histologic evidence of chorioamnionitis. Amniotic fluid concentrations of IL-6 were an independent predictor of preterm delivery, amniocentesis-to-delivery interval and neonatal morbidity and mortality. Moreover, IL-6 concentrations added significant information to the prediction of these outcomes to that provided only by clinical information such as cervical dilatation, gestational age at admission or at delivery. CONCLUSION: IL-6 is a sensitive and rapid test for the detection of microbial invasion of the amniotic cavity and for identifying women at risk for spontaneous preterm delivery and neonates at risk for morbidity and mortality.

Adult↗