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A Knight

Publications and source records attributed to A Knight.

At least 73 records · Page 4Linked to original sources
PubMed1988

Anosmia.

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Female↗
PubMed1988

Genetic evidence favouring cytotoxic T cell forbidden clones as the cause of insulin-dependent diabetes mellitus.

Recent evidence indicates that immunoglobulin light chain variable region genes are genetic determinants for Graves' disease, which is caused by autoantibodies which stimulate the thyroid gland. We have tested whether germline immunoglobulin kappa light chain variable region (V kappa) genes contribute to the genetic predisposition for IDDM. Status for the kappa light chain constant region (C kappa) allotype, Km(1), was determined in members of suitable multiplex IDDM families. Such families had two or more siblings with IDDM, together with one parent negative for Km(1) and the other heterozygous, so that each sibling had a 50% chance of receiving the kappa light chain marker. Twenty-one families of this type were found. Of the siblings, disregarding disease status, 31 were concordant with the diabetic proband for Km(1) and 29 were discordant, this close approximation to equality confirming the validity of the methodology. Of the diabetic siblings of the probands, 14 were concordant and 15 discordant. Of the non-diabetic siblings, 17 were concordant and 14 discordant. This similarity shows that V kappa genes, which are closely linked to C kappa genes, are not genetic determinants for IDDM. The contrast with Graves' disease favours the possibility that the islet beta cell destruction of IDDM is mediated by forbidden clones of cytotoxic T cells, rather than of B cells.

Diabetes Mellitus, Type 1↗
PubMed1986

Changes in plasma vasopressin concentration in association with coronary artery surgery or thymectomy.

Plasma vasopressin concentrations in 14 patients undergoing coronary artery surgery were compared with those in eight patients undergoing thymectomy. Vasopressin concentrations increased similarly in both groups on sternotomy. A second, and more marked increase was noted in the patients requiring cardiopulmonary bypass. Haemodynamic stimuli could be responsible in both groups and might explain both the similarities and the differences between the groups.

Adult↗
PubMed1986

Thyroid-stimulating autoantibodies usually contain only lambda-light chains: evidence for the "forbidden clone" theory.

Burnet's "forbidden clone" theory would predict that in patients with Graves' disease the pathogenic thyroid-stimulating autoantibody (TSab)-secreting clones arise by somatic mutation. Because each lymphocyte and its progeny are permanently committed to producing antibodies of a single light chain type, a clone arising by somatic mutation occurring in a single cell would be expected to produce autoantibodies of exclusively kappa or exclusively lambda type in an individual patient. Using affinity chromatographic techniques and monoclonal antibodies, we investigated the light chain type of TSab in 11 patients with Graves' disease. In all patients tested, TSab activity was confined to a single light chain type, confirming the recent work of Zakarija who used affinity chromatography with polyclonal antisera, but contrasting with earlier studies which used immuno-precipitation methods. Furthermore, the light chain type was lambda in 10 of the 11 patients. These observations provide support for the forbidden clone theory. In addition, the marked preponderance of patients producing TSab of the lambda-light chain type indicates that TSab are more likely to arise from the lambda repertoire of clones than from the kappa repertoire and suggests that immunoglobulin light chain V genes may be genetic determinants for susceptibility to Graves' disease.

Antibodies, Monoclonal↗
PubMed1986

A trial of intranasal Atrovent versus placebo in the treatment of vasomotor rhinitis.

Twenty-six patients with perennial rhinorrhea were treated by Atrovent, the anticholinergic agent, or placebo in a randomized double-blind crossover trial. The severity and duration of rhinorrhea were significantly reduced by Atrovent. Local side effects were more frequent with the active drug. These were reduced in a later open trial by a reduction in dosage.

Administration, Intranasal↗
PubMed1985

Passive cigarette smoking and patients with asthma.

A study of the effect of passive smoking on patients with asthma is presented. Six patients were exposed for one hour to the air in a room in which tobacco smoke was produced mechanically over that period. The effects on symptoms, lung function and airways sensitivity to inhaled histamine were then measured and compared with the same patient's responses during a control day when they inhaled smoke-free air. All six patients developed chest tightness and symptoms similar to an attack of asthma. The findings of respiratory and sensitivity tests suggest: (i) that passive smoking may trigger asthma attacks in subjects who suffer from asthma and (ii) that the airways of such subjects show increased histamine reactivity four hours after the passive smoke exposure.

Adult↗
PubMed1985

Stress ulceration in the critically ill patient.

Stress ulceration is common in patients receiving intensive care. Its cause is ill defined, life threatening complications are rare but the use of H2 antagonists and antacids in prophylaxis is widespread. The development of haemorrhage and perforation appears to be related to a group of risk factors of which sepsis may be the most important.

Antacids↗
PubMed1985

Astemizole--a new, non-sedating antihistamine for hayfever.

Astemizole, a new histamine H1 receptor blocker, was compared with placebo in an eight week, double-blind trial in the treatment of seasonal allergic rhinitis. Sixty-five patients of either sex were randomized to either astemizole (32 patients: 10 mg t.i.d. on day 1, 10 mg b.i.d. on day 2, 10 mg o.d. for the remainder of the study) or placebo (33 patients). Patients were seen bi-weekly and maintained a daily diary record of symptoms throughout the study. Significantly more patients in the placebo group (12) compared to the astemizole group (2) dropped out of the study due to treatment failure (p less than 0.05). Astemizole significantly reduced the frequency and severity of allergic symptoms. In subjective evaluations of each treatment by both the investigator and the patients, astemizole was judged good to excellent by 68% compared to 30% for placebo (p less than 0.05). One patient in each group experienced drowsiness. The only significant side effect of astemizole was weight gain (20 patients compared to 1 in the placebo group), although only one patient discontinued astemizole for this reason.

Adolescent↗
PubMed1984

The effects of a chronic infusion of arginine vasopressin in salt-restricted, water-deprived man.

The effects of a 48 h infusion of arginine vasopressin (AVP) were measured in five separate studies on four normal salt-restricted physicians, in whom fluid retention was prevented. The infusion was associated with an increase in renal sodium excretion which continued during the 24 h after the infusion had been discontinued. During the infusion plasma renin activity (PRA), plasma aldosterone and noradrenaline, and packed cell volume (PCV) fell; glomerular filtration rate, assessed by endogenous creatinine clearance, increased. The findings are best explained by a vasopressin-induced increase in plasma volume, which in the absence of fluid retention is likely to have been due to a redistribution of body water.

Adult↗
PubMed1984

Coexisting thyroid and gastric autoimmune diseases are not due to cross-reactive autoantibodies.

Some autoimmune diseases tend to cluster within families, patients with one such disease showing an increased tendency to develop certain other autoimmune diseases within the same group. We have investigated the possibility that this clustering arises because some patients produce autoantibodies which cross-react with antigenic determinants which are shared by diverse tissues. Our data indicate that this is not the case, at least so far as thyroid and gastric autoimmune diseases are concerned. This observation increases the likelihood that the real explanation for such clustering concerns sharing of idiotypic determinants by the different pathogenic clones involved or by their precursors.

Anemia, Pernicious↗
PubMed1983

Absence of allotypic variation in the autoantigen for thyroid stimulating autoantibodies.

The question of whether autoimmune reactions result from abnormality of the autoantigen or of the autoantibody is fundamental. When reaction of the thyroid stimulating autoantibodies (TSaab) of Graves' disease with their autoantigen is measured in the mouse bioassay which has a very sensitive dose-response curve this provides a favourable system for detecting any influence of allotypic variation in the autoantigen on the affinity of the corresponding autoantibodies. Seven high potency long acting thyroid stimulator (LATS) sera were tested for degree of neutralization by soluble extracts from nine thyroids, using the mouse bioassay to measure changes in LATS activity. The thyroid extracts differed in neutralizing potency and the LATS sera differed in susceptibility to neutralization, but these variations were consistent enough to enable ranking and there were no significant exceptions from especially strong or weak reactions between any individual thyroid extract and any individual LATS serum. Even autologous reactants had no greater or lesser affinity than homologous ones. Five LATS protector (LATSP) sera, tested against six thyroid extracts, including their own, again showed no evidence of allotypic variation in the autoantigen, nor did 55 LATSP sera tested with one of four thyroid extracts. Altogether we have looked at over 200 individual reactions between soluble thyroid antigen and thyroid stimulating autoantibody (LATS and LATSP). We have not found a single significant instance of any exceptionally strong or weak affinities, even with autologous antigen. The findings are in accord with Burnet's theory that autoimmune reactions are due to the emergence of forbidden clones of lymphocytes, reactive with normal self antigens.

Animals↗