Biomedical subjects

L Cairns

Publications and source records attributed to L Cairns.

22 records · Page 2Linked to original sources

PubMed1984

Anti-T cell antibody in juvenile rheumatoid arthritis.

One hundred-and-seven patients with juvenile rheumatoid arthritis (JRA) were studied for the presence or absence of an autoantibody in their sera directed against T cells. Using an indirect immunofluorescence technique on a fluorescence activated cell sorter, 71% of all patients were found to be positive on at least one sample. When studied according to the mode of onset of disease 75% of those with systemic onset, 70% with a pauciarticular, and 68% of those with a polyarticular onset were positive. Longitudinal studies appeared to suggest a correlation with disease activity, particularly in individual patients who were positive, while remission was almost invariably associated with negative testing for anti-T cell antibodies. These findings suggest that the anti-T cell antibody may be a useful diagnostic test in JRA and of benefit in monitoring disease activity and remission of disease.

Adolescent↗

PubMed1984

Changing indications for cataract surgery.

Despite the fact that two community-based surgeons switched from routine intracapsular cataract extraction to planned extracapsular cataract surgery and routine implantation of posterior chamber lenses, they did not materially increase the size of their surgical load or change their indications for cataract surgery. In contrast a similar change in surgical technique by two high-referral hospital-based surgeons was associated with a marked increase in operative rates and increased preoperative acuity. A significant proportion of this change appeared to represent reduced reluctance toward monocular cataract surgery. By eliminating the aniseikonia of monocular aphakic and visual distortion of aphakic spectacle correction, use of IOLs appears to have contributed to changing indications for cataract surgery among some ophthalmologists. A larger, more comprehensive study would be needed to determine the full extent of these trends.

Aged↗

PubMed1982

A natural model of immunologic tolerance. Tolerance to murine C5 is mediated by T cells, and antigen is required to maintain unresponsiveness.

A unique experimental model is described, where natural immunologic tolerance to a well-defined soluble native antigen (murine C5) is examined in congenic strains of mice that differ only by the presence or the absence of C5. A highly sensitive hemolytic assay was developed to detect nanogram amounts of C5 as well as an assay of anti-C5 inhibition of C5 hemolytic activity. The latter was more sensitive than immunodiffusion. Two reciprocal approaches were used to study the cellular basis of tolerance in irradiated hosts of either strain. In the first, lymphoid cells from either strain were transferred to irradiated B10.D2OSN hosts that were lacking C5 and so would not hinder detection of anti-C5 antibody upon challenge with murine C5. Second, lymphoid cells from either strain were transferred to irradiated B10.D2NSN hosts, whose native C5 provided the antigenic stimulus. The immune response of whole nonadherent spleen cell suspension as well as mixtures of T and B cells (separated on the basis of surface immunoglobulin) from either strain were studied. In addition, the duration of tolerance and the antigen requirement to maintain it in irradiated C5-deficient hosts repopulated with C5-sufficient spleen cells was examined. The positive control of irradiated C5-deficient hosts repopulated with syngeneic spleen cells showed a primary and secondary response to immunization. In contrast, C5-sufficient spleen cells failed to respond both in the primary and the secondary response. Because the unresponsiveness was not caused by antigen carryover and was not antigen specific, it represents central tolerance. In C5-sufficient irradiated hosts (where immunization was not required and antigen was present in natural form and physiological concentration), transfer of C5-deficient cells mediated a drop in C5 levels to 10-20% of that noted in unreconstituted controls. T and B cell mixing experiments from the two strains into deficient or sufficient hosts demonstrated that tolerance is T cell dependent and that C5-sufficient or -deficient B cells could cooperate with nontolerant C5-sufficient T cells to produce significant anti-C5 antibody or mediate a significant drop in C5 levels. In addition, the presence of antigen was necessary to maintain tolerance. In conclusion, these results show that (a) natural tolerance to C5 is an active process that is T cell dependent and requires the presence of antigen; (b) in this natural model, clonal abortion does not seem to occur; and (c) both tolerant and nontolerant B cells retain the capacity to produce autoantibody.

Animals↗

PubMedDate not supplied

Public-health impact of accelerated measles control in the WHO African Region 2000-03.

BACKGROUND: In 2000, the WHO African Region adopted a plan to accelerate efforts to lower measles mortality with the goal of decreasing the number of measles deaths to near zero. By June, 2003, 19 African countries had completed measles supplemental immunisation activities (SIA) in children aged 9 months to 14 years as part of a comprehensive measles-control strategy. We assessed the public-health impact of these control measures by use of available surveillance data. METHODS: We calculated percentage decline in reported measles cases during 1-2 years after SIA, compared with 6 years before SIA. On the basis of data from 13 of the 19 countries, we assumed that the percentage decline in measles deaths equalled that in measles cases. We also examined data on routine and SIA measles vaccine coverage, measles case-based surveillance, and suspected measles outbreaks. FINDINGS: Between 2000 and June, 2003, 82.1 million children were targeted for vaccination during initial SIA in 12 countries and follow-up SIA in seven countries. The average decline in the number of reported measles cases was 91%. In 17 of the 19 countries, measles case-based surveillance confirmed that transmission of measles virus, and therefore measles deaths, had been reduced to low or very low rates. The total estimated number of deaths averted in the year 2003 was 90,043. Between 2000 and 2003 in the African Region as a whole, we estimated that the percentage decline in annual measles deaths was around 20% (90,043 of 454,000). INTERPRETATION: The burden of measles in sub-Saharan Africa can be reduced to very low levels by means of appropriate strategies, resources, and personnel.

Adolescent↗