Biomedical subjects
Publications and source records attributed to E Young.
A white cyst, partially covered by jet black splotches and streaks, had a surface appearance of vanilla fudge ice cream. Histologically, the cyst was lined with two distinctly different types of follicular epithelium--one identical to that of the infundibulum and the other to that of the matrix. The black pigment was melanin, produced by numerous dendritic melanocytes that were situated only in the region of the epithelium-resembling matrix.
Fatal cases of cordophilosis and gastro-intestinal verminosis in eland are reported. Some of these cases were complicated with heartwater or cytauxzoonosis. Cordophilosis resulted in acute cardiac arrest. Infestations with gastro-intestinal namatodes were responsible for extreme emaciation. Clinically affected eland responded dramatically to systemic treatment with levamisole hydrocholride.
Pulmonary hypertension was shown to occur in wild young zebra and wildebeest subject to forced exercise over 2 to 5 km distance. Measurements of pulmonary arterial pressure were made on a Devices recorder connected to a catheter passed via the jugular vein. Systemic pressure was recorded after puncture of the dorsal aorta. The electrocardiogram, PO2, PCO2 and pH were determined and enzyme levels such as CPK were estimated. Reduction of the pulmonary hypertension occurred after bicarbonate infusion.
Clinical, electrocardiographic and cineventriculographic data in two patient groups were analyzed to define the natural history of S-T segment elevation after myocardial infarction. In sixteen of 22 patients (73 percent) with acute inferior myocardial infarction, S-T segment elevation was present on hospital admission, persisting in 1 (5 percent) by the 2nd week. S-T segment elevation was present on admission in 18 of 23 patients (78 per cent) with acute anterior myocardial infarction and persisted in 13 after 1 week and in 9 of 14 (64 percent) during a follow-up period of 1 to 6 months. S-T segment elevation lasting more than 2 weeks after myocardial infarction did not resolve. Compared with patients with inferior myocardial infarction or anterior infarction without persistent S-T segment elevation, patients with anterior infarction and persistent S-T segment elevation had a higher level of mean maximal serum creatine phosphokinase (CPK), more severe left ventricular decompensation and a greater frequency of death in the early follow-up period. In a separate series of 95 patients with cineangiographically documented coronary artery disease, 40 of 65 patients (62 percent) with advanced anterior and apical asynergy had persistent S-T segment elevation. By contrast, only 1 of 30 (3 percent) with coronary disease and normal ventriculograms had persistent S-T segment elevation. We concluded that (1) the natural history of S-T segment elevation after myocardial infarction is resolution within 2 weeks in 95 percent of inferior but in only 40 percent of anterior infarctions; (2) S-T segment elevation persisting more than 2 weeks after myocardial infarction does not resolve; (3) persistent S-T segment elevation is associated with clinically more severe myocardial infarction; and (4) in patients with coronary artery disease, persistent S-T segment elevation after myocardial infarction is a specific but insensitive index of advanced asynergy.
Allergenic substances have been isolated from cultures of Dermatophagoides pteronyssinus on wheat germ flakes and powdered yeast; as controls, non-sterile nutrient medium containing no mites, as well as sterile medium, were maintained and extracted under identical conditions. Chemical purification and analyses indicated the occurrence of skin-active allergens in all three preparations. This was confirmed by the assay of skin-reactivity in vivo and complement-inactivating capacity in vitro. Quantitatively, the medium containing bacteria and fungi contained more allergen than the sterile control, but less than the mite-infected medium. The evidence indicates that degradation reactions of nutrient components proceed faster in the non-sterile media than in the sterile control. The results of immunochemical analyses demonstrate that degradation reactions, give rise to the introduction of lysine-sugar structures inot high-molecular weight components from the medium. It is concluded that mites and micro-organisms have a role in allergen formation by promoting degradation reactions among nutrient constituents.
The specific activities of lysosomal hydrolases in cultured skin fibroblasts and amniotic fluid cells showed wide and unpredictable variations between cultures, which may lead to difficulty in differentiating normal, heterozygous, and homozygous cells. However, the variability for a given culture was similar for all enzymes assayed, so that a clearer differentiation of a relative deficiency of a given enzyme could be obtained by expressing its activity in ratio to that of another enzyme. Activity ratios were particularly useful in the evaluation of enzyme levels in cultured amniotic fluid cells. Results of their application to tests of pregnancies at risk for metachromatic leucodystrophy, Krabbe's leucodystrophy, GM1-gangliosidosis, and GM2-gangliosidosis (Sandhoff variant) are presented.
The effect of long-wave ultraviolet light on psoriasis was studied in 10 patients, using the method of paired comparisons. The radiation failed to have any demonstrable effect.
The transverse plane QRS loop vectorcardiogram (VCG) was analyzed in 102 consecutive patients, angiographically proven to have coronary artery disease (CAD), whose right anterior oblique left ventriculogram showed severe asynergy (akinesis or marked hypokinesis) of the anterior and apical segments. Eighty-four of the 102 loops were considered to be diagnostic of severe asynergy because similar loops were not found in patients with CAD with less severe asynergy of either or both segments or in normal control subjects. Eighty-two of the 84 showed a uniformly abnormal pattern. Posterior vectors exhibited partial or complete clockwise "rotation" and were much more prominent than early anterior forces. In fact, the latter were often absent. In the other two VCG's at least the early half of the loop displayed prominent anterior vectors. The ECGs showed marked variability of the QRS in leads V-2-V-6. Abnormal Q waves were present in only 63 of the 102. The numbers of these leads showing abnormal Q waves varied from one to all of these positions.
Echinococcosis has been diagnosed in the following wild species in the Kruger National Park : lion, Panthera leo, spotted hyena, Crocuta crocuta, Cape hunting dog, Lycaon pictus, Burchell's zebra, Equus burchelli antiquorum, buffalo, Syncerus caffer, hippopotamus, Hippopotamus amphibius, and impala, Aepyceros melampus. Infestation rates in the herbivores vary from 60% in zebra to less than 1% in impala. Species like elephant, Loxodonta africana, and blue wildebeest, Connochaetes taurinus, do not seem to be susceptible. The successful artificial transmission of Echinococus granulosus felidis from Burchell's zebra to the lion is reported for the first time.
Hepatozoonosis was studied in hyaenas, lions, jackals, cheetahs and one leopard in the Kruger National Park and compared with the condition seen in dogs in the Republic of South Africa. Hepatozoon schizonts were found in the wild carnivores. The genesis of microschizonts was followed and is illustrated. The schizonts were sometimes very plentiful in the lung, myocardium and skeletal muscle, and were also encountered in the spleen, liver and lymph nodes. Gametocytes were present in leucocytes. The host response was usually very mild. sporogenous development in ticks was observed in Rhipicephalus simus females removed from an infected hyaena and R. sanguinelus adults fed on an infected jackal in the nymphal stage. Attempts to transmit Hepatozoon from a jackal to dogs by means of ticks gave inconclusive results.
Armillifer armillatus, Linguatula serrata and L. nuttalli have each been isolated from nine different mammalian species in the Kruger National Park: lion, Panthera Leo; Leopard, P. pardus; buffalo, Syncerus caffer: blue wildebeest, Connechaetes taurinus; giraffe, Girraffa camelopardalis; kudu, Tragelophus strepsiceros; waterbuck, Kobus ellipsyprymnus; tsessebe, Damaliscus iunatus and impala, Aepyceros melampus. Successful transmission of L. serrata from the lion to a domestic ox and impala is recorded for the first time. Pentastomiasis is also a disease of man and these findings are possibly of epidemiological significance.
In Africa trichinosis is essentially a disease of wild carnivores. Once established in a suilline cycle it becomes a more important threat to man. The results of tests on 8,000 specimens of 20 wildlife species in the Kruger National Park are discussed and the epizootiology of trichinosis in South Africa is briefly reviewed. The first case of trichinosis in an African civet, Viverra civetta Schreber, 1776, is reported. The confirmed absence of trichinosis in true herbivores is of practical significance in view of the increasing utilization of game meat as food.
Lions in the Kruger Park have been found affected by a variety of parasitic and other disease conditions, including trichinosis, filariasis, sarcoptic mange, pentastomiasis, echinococcosis, taeniasis, hepatozoonosis, anthrax, babesiosis and rickets. Six of these may be directly or indirectly transmissible to man or are, at least, closely related to human parasites or disease. Nine of these diseases, or closely related conditions, are also known to infect domestic animal species. The opposite may, of course, also be true--man and his domestic animals may, under certain circumstances, transmit certain diseases to lions, presumably sometimes with fatal results.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.