Publications by authors named "Larrick J"

We have tested the hypothesis that the abnormal development of the central nervous system seen in endemic cretinism might be accompanied by concurrent abnormal dermatoglyphic patterns. We compared digital and palmar dermatoglyphics of normal individuals and endemic cretins inhabiting the Huon Peninsula of Papua New Guinea. The population sampled from the Irumu River Valley included 118 males and 114 females with 22 male cretins and 23 female cretins.

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Three out of seven serum samples from Ecuadorian Indians had very high antibody levels against Bothrops nasutus venom, and IgG concentrates of these sera effectively neutralized this venom when subsequently injected into mice. It is concluded that the high mortality rate among these Indians would be even higher if there were not such natural protection. Further research into active immunization of humans should be encouraged.

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The Waorani Indians of eastern Ecuador have the highest blood concentration of IgE reported in a human population. Evidence obtained by medical history, physical examination, and immediate hypersensitivity skin tests suggests that pollen allergy and other atopic diseases are rare among the Waorani. A similar association between parasite-induced hyperimmunoglobulinemia-E and a low prevalence of conventional atopic disease has been reported in numerous other tropical populations.

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A dermatoglyphic study was made of two high-altitude populations inhabiting the same ecozone in extreme northwest Nepal. Despite cultural and linguistic differences there appears to be a significant amount of dermatoglyphic homology between the Buddhist-Tibetan villages and their Hindu-Caucasian neighbors.

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Serum samples from 223 Waorani Indians, a tribe in eastern Ecuador, were investigated by enzyme-linked immunosorbent assay for antibodies to snake venom. Seventy-eight per cent were positive, confirming the highest incidence and mortality from snake bite poisoning yet recorded in the world. Most samples were positive for more than one venom antibody.

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Blood samples from 448 people living in six villages in the Huon Peninsula in northeast Papua, New Guinea, were tested for Gm(1,2,3,5,6,10,11,13,14,17,21,24,26) and Inv(1) [Km(1)]. All the people are non-Austronesian (NAN) speakers. As expected, there was a low frequency of the Gm1,3,5,10,11,13,14,26 haplotype, but in contradiction to expectations there was a complete absence of Gm1,2,17,21,26 haplotype.

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The Waorani Indians of Eastern Ecuador have the highest blood levels of immunoglobulin E that have been recorded in a human population. Using a radial immunodiffusion technique for IgE determination, we found the mean plasma IgE concentration for the entire sample (n = 227) to be 11,975 International Units per milliliter (normal: 5--500 IU/ml). The reason for the elevated IgE concentrations is unclear, although genetic factors and a high prevalence of parasitic infection may be involved.

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When cells of human macrophage-like cell line U937 are cultured in the presence of medium conditioned by mixed lymphocyte culture (MLC), PHA- or Con A-stimulated lymphocytes they demonstrate morphologic and functional characteristics of stimulation. The cells become larger, their surface more villous, and the cytoplasm has increased numbers of lysosomes and phagosomes. There is a marked (at least 10-fold) increase in antibody-dependent cellular cytotoxicity (ADCC) against both erythroid and tumor targets accompanied by increased expression of Fc receptors (FcR).

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The Waorani Indians of eastern Ecuador provide a unique opportunity for studying exposure of an isolated human population to various infectious disease agents. Using serologic tests to determine antibody prevalence, skin test data, and stool examination for parasites, we have been able to construct a profile of infectious diseases which are endemic, and others which have been introduced into the Waorani population. These findings are compared with similar data reported from elsewhere in the Amazon.

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Serum samples from children and adults from several countries were tested by radioimmunoassay for antibody to the Norwalk virus. Antibody was commonly found in adults from all the countries tested. Antibody appears to be acquired more rapidly in children from underdeveloped countries than in children from the United States.

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Experiments demonstrating the existence of receptors for iron-saturated transferrin on both B and T lymphoblastoid cell lines of human origin are described. Binding of 125I-labeled transferrin is rapid, saturable and reversible. It can be specifically inhibited by unlabeled transferrin but not by other proteins.

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This report describes investigations of plasma membrane transferring receptors on a variety of lymphoid cell lines and normal peripheral blood lymphocytes during activation and cell growth cycles. Transformed lymphoid cell lines have as many as 1,000 times the number of receptors found on normal resting lymphocytes. The number of iron transferrin receptors on continuous cell lines as well as normal human fibroblasts is down-regulated during the transition from log-phase growth to stationary plateau growth.

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