Search PubMed⌕ Search

Biomedical subjects

R Collins

Publications and source records attributed to R Collins.

At least 235 records · Page 13Linked to original sources
PubMed1976

Immunoglobulin G complex interactions with rheumatoid factor and neutrophils: 51CrCl3 labelling and 14CO2 hexose monophosphate shunt studies.

The interactions of soluble and insoluble IgG complexes with macromolecular rheumatoid factor (RF) and neutrophils have been examined in an in vitro system allowing the separate assay of the biologic activities of these elements in the rheumatoid inflammatory process. Studies utilizing soluble and insoluble 51CrCl3 labelled human IgG complexes have demonstrated uptake of only the insoluble complexes by human neutrophils. A burst of hexose monophosphate shunt activity, as evidenced by increased oxidation of glucose-l-14C to 14CO2, has been shown to occur only when neutrophils are exposed to these insoluble complexes. High titer RF sera added to the insoluble complexes prior to their incubation with neutrophils did not affect either the uptake of the complexes or the magnitude of hexose monophosphate shunt activity. Native IgG and soluble IgG complexes were not taken up by the neutrophils and did not stimulate hexose monophosphate shunt activity in the presence or absence of rheumatoid sera. The addition of high titer RF sera to soluble IgG complexes produced precipitation of RF-IgG complexes which were capable of stimulating hexose monophosphate shunt activity in normal neutrophils. RF thus has been shown to change functionally inactive soluble complexes into functionally active insoluble complexes capable of stimulating normal neutrophils. Neutrophil stimulation by insoluble complexes may be important in the continuing inflammatory process occurring in the joints of patients with rheumatoid arthritis.

Arthritis, Rheumatoid↗
PubMed1976

Neutrophil and rheumatoid factor-Immunoglobulin G insoluble complex interactions: phagocytosis and sequelae.

Studies utilizing 51CrCl3 labelled human immunoglobulin G have demonstrated a quantitative, time-related increase in the uptake of insoluble rheumatoid factor-immunoglobulin G complexes by human neutrophils. A burst of hexose monophosphate shunt activity occurs when these complexes are phagocytized by neutrophils as evidenced by the increased oxidation of glucose-l-14C to 14CO2. Metabolic and electron micrographic studies suggest that a heat stable serum factor is needed for maximum complex uptake and shunt activity. Phagocytosis of complexes did not affect the adherence of neutrophils to nylon fiber columns, but did not produce selective release of lysosomal enzymes. This study has delineated in an in vitro system, functional and metabolic sequelae of neutrophil phagocytosis of insoluble rheumatoid factor-immunoglobulin G complexes, which may be important components of the inflammation occurring in the joints of patients with rheumatoid arthritis.

Glucuronidase↗
PubMedDate not supplied

CAH or SLE?

Explore the source record for details and available documents.

Fluorescent Antibody Technique↗
PubMedDate not supplied

Avoidance of large biases and large random errors in the assessment of moderate treatment effects: the need for systematic overviews.

In order to avoid selective biases and to minimize random errors, inference about the effects of treatment on serious endpoints needs to be based not on one, or a few, of the available trial results, but on a systematic overview of the totality of the evidence from all the relevant unconfounded randomized trials. But, only where coverage of all, or nearly all, randomized patients in all relevant trials (or a reasonably unbiased sample of such trials) can be assured, is a systematic overview of trials reasonably trustworthy, for then any selective biases are likely to be small in comparison with any moderate effects of treatment. Checks for the existence of such biases can best be conducted if reasonably detailed data are available from each trial. Future trials should take into account the results of any relevant overviews in their design, and should plan to obtain sufficient numbers of events to contribute substantially to such overviews. In many cases, this implies the need for randomized trials that are much larger than is currently standard.

Clinical Trials as Topic↗