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Biomedical subjects

W J Hall

Publications and source records attributed to W J Hall.

At least 127 records · Page 7Linked to original sources
PubMed1970

Studies on tuberculin fever. IV. The passive transfer of reactivity with various tissues of sensitized donor rabbits.

Utilizing techniques of passive transfer, we have investigated the factors responsible for production of fever when tuberculin is given intravenously to specifically sensitized rabbits. The ability to develop a febrile response to tuberculin could be passively transferred to normal recipients with viable mononuclear cells from peritoneal exudates, spleen, or lymph nodes of donor rabbits sensitized with BCG. Sensitivity was usually apparent 48 hr after transfer, maximal at 7 to 14 days, and rapidly declined thereafter. Granulocytes and nonviable, sonicated, mononuclear cells from similarly sensitized donors were unable to transfer this form of reactivity. Passive transfer of reactivity was also effected with plasma and serum, suggesting that the reaction of antibody with antigen contained in tuberculin is one of the initial steps by which the host cells are activated to release the endogenous pyrogen (EP) that mediates this form of hypersensitivity fever. An intravenous infusion of granulocytes, as well as of several types of mononuclear cells from sensitized donors, made most recipients responsive to the pyrogenic effect of old tuberculin (OT) given 2 hr later. Some of these passively transferred cells, such as the granulocyte and alveolar macrophage, may be activated in vivo by OT, as they are in vitro. However, in the case of splenic and lymph node cells that cannot be activated by OT to produce EP in vitro, it seems likely that an intravenous injection of OT causes these transferred, sensitized cells to liberate an intermediate substance that either directly, or in association with antigen, activates the host's normal cells to produce EP. In support of previous suggestions that leukocytes of several types, as well as phagocytic cells of the reticuloendothelial system, serve as potential sources of EP in tuberculin-induced fever, evidence was presented that OT also activates both granulocytes and mononuclear cells from sterile exudates of BCG-sensitized donors to produce EP in vitro.

Animals↗
PubMed1966

The action of ketonic prostaglandins on the guinea-pig myometrium.

1. Prostaglandin E(1) or E(2) has two clearly distinguishable effects on the guinea-pig myometrium in vitro.2. The first of these, the ;direct' effect, is manifested by contraction accompanied by spiking, is readily modified by changes in the concentrations of Mg(2+), Ca(2+) and K(+) in the suspension medium, and does not long outlast the presence of the prostaglandin in the organ-bath. In this respect it resembles the responses to other stimulants.3. The second effect is manifested by ;enhancement' of the responses to non-specific stimulation, whether this be by chemical or electrical means. Enhancement may be demonstrated for up to 20-80 min after the PGE(1) or PGE(2) has been washed out of the organ-bath, and during this time the myometrium shows no consistent changes in electrical activity or in resting mechanical tension that may be associated with the enhancement effect. Enhancement following PGEs is not readily affected by moderate changes in the Mg(2+), Ca(2+) or K(+) concentrations of the suspension medium, and in all these respects it differs markedly from the effects of other stimulants.4. K(+)-depolarized myometrial preparations show feeble direct responses to PGEs, like those to other stimulants. They also show post-PGE enhancement of the responses to other stimulants, but not of the responses to electric field stimulation.5. The empirical method used for measuring the enhancement effect is examined critically.6. The possible mechanisms of the direct and enhancement effects are discussed. It is postulated that they involve actions at two different sites, which may be on two different types of cell but are more likely to co-exist on the same cells. The direct effect is postulated to result from depolarization at the exposed cell membrane, whereas enhancement may result from facilitation of excitation-contraction coupling.

4-Aminobenzoic Acid↗
PubMedDate not supplied

Airway hyperreactivity and a history of clinical manifestations of asthma in childhood.

The relationship between airway hyperreactivity and a history of the clinical manifestations of asthma was investigated in 54 children between the ages of 8 and 12. Airway reactivity was assessed by measuring the change in pulmonary function following the hyperventilation of subfreezing air. Clinical manifestations of asthma were assessed by a standardized questionnaire regarding lower respiratory symptoms and by medical records review. The subjects were participating in a study of the sequelae of bronchiolitis; 25 had seen a physician for mild bronchiolitis during the first 2 years of life, and the remainder had not. Airway hyperreactivity was demonstrated in 8 of the 54 children and correlated with use of medication for asthma in the 2 years before pulmonary testing and positive parental response to the question, "Does your child wheeze apart from colds?" Airway hyperreactivity did not correlate with a history of other respiratory symptoms or with a history of physician-diagnosed wheezing or asthma. No questionnaire or chart review item identified over 50% of the children with reactive airways, and most subjects identified by each of the items did not demonstrate hyperreactive airways. These data suggest that airway reactivity is only weakly associated with a history of the clinical manifestations of asthma in childhood, in part because children with clinically inactive asthma do not consistently demonstrate airway hyperreactivity and in part because many children with hyperreactive airways have never had respiratory symptoms.

Asthma↗