Blood eosinophil degranulation and vacuolation in helminthic infection.

Blood eosinophil degranulation and vacuolation were studied in 21 Nigerian medical patients with helminthic infection and in 10 uninfected controls. For both patients and controls, 200 blood eosinophils were assessed 'blind' by light microscopy for the number of cytoplasmic vacuoles and the loss of specific cytoplasmic granules. In the helminth-infected patients (N = 21) the mean percentage (+/- S.D.) of eosinophils with one or more but less than 10 cytoplasmic vacuoles was 0.7 +/- 0.8%, that with loss of less than half of specific cytoplasmic granules was 1.6 +/- 1.7%, that with 10 or more cytoplasmic vacuoles was 0.1 +/- 0.2%, and that with loss of half or more specific cytoplasmic granules was 0.3 +/- 0.6%. There was no significant difference between patients and controls (P less than 0.05). We conclude that helminthic infection is not associated with blood eosinophil degranulation and vacuolation. The finding of large numbers, e.g. 15% or more, of vacuolated and especially degranulated eosinophils in patients with helminth-related eosinophilia should not be attributed to the helminthic infection alone, but should raise the suspicion of eosinophil-mediated host tissue damage.

Tolerance of weanling pigs for dietary vitamin A and D.

Weanling cross-bred pigs (36 or 48) were caged individually and fed diets containing a supplement of vitamin A (Expt 1) or vitamin D3 (Expt 2) at levels representing 1, 5, 10, 25, 50 and 100 times the NRC (1988) estimated requirements, for 4 weeks. Growth rate, feed intake and feed/gain ratio were not influenced significantly. In Expt 1 the plasma retinol concentrations were at 4 weeks, respectively, 31.7, 39.4, 43.2, 42.9, 44.4, and 46.3 micrograms/dl (P less than 0.05). In Expt 2, the plasma 25(OH)D3 concentrations were at 2 weeks, respectively, 22.5, 29.5, 35.7, 46.2, 79.9, 135.3 ng/ml (P less than 0.001). Histological examination of lung, stomach, kidney, liver and heart indicated no abnormalities, but focal microscopic lesions consistent with osteochondrosis were found in pigs receiving vitamin A at levels over 10 times the requirement. The incidence of osteochondrosis at 2 weeks was, respectively, 0/8, 0/8, 0/8, 0/8, 0/8, and 1/8, and at 4 weeks was, respectively, 0/8, 0/8, 0/8, 2/8, 2/8 and 2/8. The NRC (1988) estimate of the requirement for vitamin D may be somewhat low since the concentration of plasma 25(OH)D was lower with 200 or 1,000 IU vitamin D/kg diet than at the start.

Involvement of water-soluble vitamins in diseases of swine.

The various roles of the water-soluble vitamins (including choline and vitamin C) in diseases of swine are outlined. The most important role is in the prevention of deficiency disease; another important role is in relation to the immune response. Deficiency signs relating to each vitamin are described and the metabolism of each vitamin is outlined. Recent estimates of requirements are set out, together with suggestions on supplementation of practical diets for swine.

Enhancement of phagocytosis of parasitized and nonparasitized red cells in acute Plasmodium berghei malaria.

The phagocytosis by mouse peritoneal macrophages of parasitized red cells (PRCs) and nonparasitized red cells (nonPRCs) separated from Plasmodium berghei infected blood was studied in vitro. Peritoneal macrophages from acutely infected mice and normal mice were cultured on coverslips. PRCs and nonPRCs were fractionated by Ficoll density gradient centrifugation from Plasmodium berghei infected blood. PRCs were fed in triplicate cultures to normal macrophages in normal serum, normal macrophages in acute serum, acute macrophages in normal serum, and acute macrophages in acute serum. Similarly, nonPRCs were fed to macrophages in the same combinations of normal and acute macrophages and serum. In acute serum, acute macrophages ingest PRCs significantly more readily than normal macrophages (p less than 0.05). Acute macrophages in acute serum ingest PRCs more readily than acute macrophages in normal serum, but the difference does not achieve statistical significance. Acute serum apparently decreases the phagocytosis of PRCs and nonPRCs by normal macrophages, perhaps because of an inhibitory antibody present in acute serum. As with PRCs, in the presence of acute serum, acute macrophages ingest nonPRCs significantly more readily than normal macrophages (p less than 0.05).

Sarcoid in a Nigerian: geographical variation of the frequency of sarcoid among blacks considered.

A 30-year-old Nigerian male with sarcoid manifested by hilar and peripheral lymphadenopathy is presented. Sarcoid and other immune disorders such as systemic lupus erythematosus and polymyositis are rare in Africa. In contrast, these disorders, and especially sarcoid, display a predisposition for blacks in the USA where blacks are affected by sarcoid 10 times as frequently as whites. The importance of reporting and, where possible, immunological study of African patients with sarcoid is emphasized.

Anti-reproductive and other medicinal effects of Tropaeolum tuberosum.

Tropaeolum tuberosum is an edible-tuber-producing cultigen of the Andes mountains. Historical beliefs relating to the effects of this species on human reproductive potential continue to the present day. T. tuberosum subsp. tuberosum contains p-methoxybenzylglucosinolate as its major secondary metabolite. The putative anti-aphrodisiac activity of T. tuberosum was examined in male rats fed a diet containing tubers of this taxon. Experimental animals and controls showed equal capability in impregnating females, although animals fed T. tuberosum showed a 45% drop in their blood levels of testosterone/dihydrotestosterone. This decrease appears to be related to the presence of isothiocyanates in the tubers. Feeding studies of female guinea pigs and in vitro studies to test the 17 beta-estradiol binding inhibition of plant extracts and of pure isothiocyanates failed to substantiate any estrogenic activity of these taxa. However, preliminary results suggest that N, N-di-(methoxy-4-benzyl)thiourea competitively inhibits estradiol binding and may have estrogenic activity. The antibiotic, insecticidal, nematocidal and diuretic properties of isothiocyanates substantiate several of the uses of T. tuberosum in Andean folk medicine.

Black contributions to the early history of Western medicine: lack of recognition as a cause of black under-representation in US medical schools.

During several millenia, blacks in ancient Egypt made numerous contributions to medicine and were acknowledged as the inventors of the art of medicine. They produced the earliest physicians, medical knowledge, and medical literature. They contributed to the development of medicine in ancient Greece. Ancient writers, including Herodotus, Isocrates, and Diodorus, affirm this. Modern presentations of ancient medicine, however, deprive blacks of the knowledge of their early contributions to medicine by ignoring or subtly misrepresenting the black identity of the ancient Egyptians. Blacks are currently under-represented in US medical schools. It is proposed that the recognition of the contributions of blacks to the early history of Western medicine would inspire black students to study medicine.

A method for separating estrogens and phytoestrogens on Sephadex LH-20 columns.

A procedure for separating estrogens from phytoestrogens in animal fluids is presented. The use of Sephadex LH-20 in absolute methanol permits a simple separation and allows the measurement of phytoestrogen levels in plasma and urine by the competitive binding assay. This method facilitates a more accurate measure of the hormonal balance in animals with an exogenous input of phytoestrogens.