Factors favoring the onset and continuation of rheumatic fever

Rheumatic fever is one of the most important of diseases economically, not only because of its acute manifestations, but also because of its rôle in the production of between 30 and 40 per cent of chronic cardiac disease in the latitude of the North Atlantic States. Microscopic findings indicate it to be a widespread disease involving by preference mesenchymal structures or mesenchymal protions of parenchymatous organs. Physiological stress and strain appear to favor localization of its manifestations, although it may be locally active without giving rise to symptoms; and various vulnerable organs may be either simultaneously or independently involved.A number of factors appear to have causative relationships. Climatic conditions such as exist in temperate zones in winter favor its development; while sunny dry summers and tropical weather inhibit or prevent its evolution. Among the poorer classes it is from fifteen to twenty times more prevalent than in persons better housed and fed. Malnutrition and mild toxic states are frequent precursors of characteristic attacks. Most patients, both children and adults, give a history of repeated nonspecific infections of the respiratory tract, tonsils, sinuses, or middle ear, extending over several years, before a typical attack of rheumatic fever is ushered in by a severe focal infection. Persons in intimate contact with patients during acute outbursts of rheumatic fever not infrequently suffer simultaneously from upper respiratory infections, or from typical rheumatic fever; hence there seems to be a distinct communicable factor favoring its spread. Because chronicity and relapses are so frequent, and crippling cardiac damage is of such gradual evolution, and finally because laboratory tests often reveal activity in periods between attacks, it seems justifiable to consider the infection to be characterized by long periods of preparation or sensitization of the tissues, the result of repeated mild infection before a more intense focal infection sets off the violent explosion recognized as acute rheumatic fever. Similar mild infections, more-over, apparently favor the continuation of true rheumatic activity in viscera already involved. It seems logical, therefore, to regard these preparatory periods and mild chronic infections between acute out-breaks as essential parts of the morbid process; hence our therapeutic and prophylactic efforts should be directed against them as well as against the more acute manifestations of the disease.     

REACTION OF RABBITS TO STREPTOCOCCI: COMPARATIVE SENSITIZING EFFECT OF INTRACUTANEOUS AND INTRAVENOUS INOCULA IN MINUTE DOSES

1. Rabbits were rendered very hypersensitive by relatively small doses of green streptococci given intracutaneously, and somewhat less hypersensitive by similar doses of heat-killed vaccine prepared from hemolytic streptococci. 2. Animals receiving the same doses intravenously gave, upon subsequent testing, lesions slightly more marked than normal controls; but these lesions were qualitatively hard and nodular compared with the large edematous lesions in the cutaneously sensitized group. 3. There was no parallelism between the degree of cutaneous or ophthalmic hypersensitivity and agglutinin titer in the blood serum. 4. Bacterial hypersensitivity to whole streptococci appears to depend more upon previously induced focal infection than upon circulating antibodies.     

Qualitative research in nutrition and dietetics: data analysis issues

Although much of the analysis conducted in qualitative research falls within the broad church of thematic analysis, the wide scope of qualitative enquiry presents the researcher with a number of choices regarding data analysis techniques. This review, the third in the series, provides an overview of a number of techniques and practical steps that can be taken to provide some structure and focus to the intellectual work of thematic analysis in nutrition and dietetics. Because appropriate research methods are crucial to ensure high‐quality research, it also describes a process for choosing appropriate analytical methods that considers the extent to which they help answer the research question(s) and are compatible with the philosophical assumptions about ontology, epistemology and methodology that underpin the overall design of a study. Other reviews in this series provide a model for embarking on a qualitative research project in nutrition and dietetics, an overview of the principal techniques of data collection, sampling and quality assessment of this kind of research and some practical advice relevant to nutrition and dietetics, along with glossaries of key terms.