A survey of serum and dietary carotenoids in captive wild animals.
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Accumulation of carotenoids varies greatly among animal species and is not fully characterized. Circulating carotenoid concentration data in captive wild animals are limited and may be useful for their management. Serum carotenoid concentrations and dietary intakes were surveyed and the extent of accumulation categorized for 76 species of captive wild animals at Brookfield Zoo. Blood samples were obtained opportunistically from 275 individual animals immobilized for a variety of reasons; serum was analyzed for alpha- and beta-carotene, lutein + zeaxanthin, lycopene, beta-cryptoxanthin and canthaxanthin. Total carotenoid content of diets was calculated from tables and chemical analyses of commonly consumed dietary components. Diets were categorized as low, moderate or high in carotenoid content as were total serum carotenoid concentrations. Animals were classified as unknown, high, moderate or low (non-) accumulators of dietary cartenoids. Nonaccumulators had total serum carotenoid concentrations of 0-101 nmol/L, whereas accumulators had concentrations that ranged widely, from 225 to 35,351 nmol/L. Primates were uniquely distinguished by the widest range of type and concentration of carotenoids in their sera. Most were classified as high to moderate accumulators. Felids had high accumulation of beta-carotene regardless of dietary intake, whereas a wide range of exotic birds accumulated only the xanthophylls, lutein + zeaxanthin, canthaxanthin or cryptoxanthin. The exotic ungulates, with the exception of the bovids, had negligible or nondetectable carotenoid serum concentrations despite moderate intakes. Bovids accumulated only beta-carotene despite moderately high lutein + zeaxanthin intakes. Wild captive species demonstrated a wide variety of carotenoid accumulation patterns, which could be exploited to answer remaining questions concerning carotenoid metabolism and function. (+info)
Particle deposition in the trachea: in vivo and in hollow casts.
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The pattern of deposition within the respiratory tract of potentially harmful particulates is a major factor in assessing any risk from individual and community exposures. Although the trachea is the most easily observed of the conductive airways, very little information concerning its particle collection characteristics is available, information which is essential for a complete and realistic description of particle deposition patterns within the entire respiratory tract. Data on tracheal deposition are also needed for development of accurate predictive models for particle deposition. The pattern of particle deposition in the trachea, and its relation to air flow, was studied in a hollow cast of the human larynx-tracheobronchial tree. Results were compared with data obtained in humans in vivo and from previous studies in hollow casts. In addition, the relevance of tracheal deposition in the hollow cast test system to deposition in vivo was examined by a direct comparison of deposition in a cast prepared from the lungs of donkeys previously studied in a series of in vivo tests. The disturbance of the air flow within the trachea caused by the larynx promoted the deposition of suspended particulates throughout the length of the trachea, and especially in proximal regions. This proximal deposition was due both to direct impaction from the air jet coming from the glottis and to effects of the tubulent flow. Turbulence produced inhomogenous deposition patterns within the trachea for particles of all sizes, although its effect was more pronounced as size decreased. Tracheal deposition in the human cast was within the range of normal in vivo tracheal depostion only when a larynx was used during cast test exposures; this emphasizes the need for the use of realistic experimental test systems for the study of particle deposition patterns. The relative patterns of deposition in casts of the donkey trachea and in the same tracheas in vivo were similar. (+info)
Specific cleavage analysis of mammalian mitochondrial DNA.
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Mitochondrial DNA from several mammalian species has been digested with a site-specific restriction endonuclease (HaeIII) from Haemophilus aegyptius. A quantitative analysis of the resulting specific fragments indicates that the mtDNA of any individual mammal is predominantly a single molecular clone. Gel analysis of specific cleavage products has proven quite sensitive in detecting differences in mtDNA: mtDNAs from the more distantly related mammals studied (e.g., donkey and dog) are found to have few bands in common and very closely related mammals (e.g., donkey and horse) share only about 50% of their bands. This procedure has detected several intraspecies mtDNA differences. Six distinct human patterns have been found, with one pattern usually differing from another in two or three bands. mtDNAs from different organs of single individuals have also been analyzed, and no differences have been found. (+info)
Anthracycline cardiotoxicity in a black rhinoceros (Diceros bicornis): evidence for impaired antioxidant capacity compounded by iron overload.
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Two weeks before dying of congestive heart failure, a juvenile black rhinoceros (Diceros bicornis minor) received a single low dose of doxorubicin as part of combination chemotherapy for acute lymphoblastic leukemia. Diffuse hemosiderosis was present at necropsy in a pattern indicative of dietary iron overload, but unique iron-positive degenerative lesions were found in isolated myocardiocytes. Serum analyses revealed hyperferremia, 87% transferrin saturation, and 5- to 10-fold elevations in ferritin concentration, reflecting markedly increased tissue iron stores. Since both toxic and therapeutic effects of anthracyclines are mediated by formation of reactive free radicals via iron-catalyzed reactions, these observations suggest that iron overload may have enhanced myocardial susceptibility to cardiotoxic effects of doxorubicin. Impairments in other myocardial antioxidant defenses, such as deficiencies in catalase and glutathione S-transferase that are known to exist in rhinoceros erythrocytes, may have been underlying factors contributing to an inherent sensitivity of rhinoceros tissues to oxidant-induced injury. (+info)
Model dependence of the phylogenetic inference: relationship among carnivores, Perissodactyls and cetartiodactyls as inferred from mitochondrial genome sequences.
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Some previous analysis of mitochondrial proteins strongly support the Carnivora/Perissodactyla grouping excluding Cetartiodactyla (Artiodactyla + Cetacea) as an outgroup, but the support of the hypothesis remains equivocal from the analysis of several nuclear-encoded proteins. In order to evaluate the strength of the support by mitochondrial proteins, phylogenetic relationship among Carnivora, Perissodactyla, and Cetartiodactyla was estimated with the ML method by using the updated data set of the 12 mitochondrial proteins with several alternative models. The analyses demonstrate that the phylogenetic inference depends on the model used in the ML analysis; i.e., whether the site-heterogeneity is taken into account and whether the rate parameters are estimated for each individual proteins or for the concatenated sequences. Although the analysis of concatenated sequences strongly supports the Carnivora/Perissodactyla grouping, the total evaluation of the separate analyses of individual proteins, which approximates the data better than the concatenated analysis, gives only ambiguous results, and therefore it is concluded that more data are needed to resolve this trichotomy. (+info)
Rosette-forming ability of thymus-derived lymphocytes in cell-mediated immunity. I. Delayed hypersensitivity and in vitro cytotoxicity.
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Effector cells in delayed hypersensitivity and in vitro cytotoxicity were studied in lymph node cells from animals immunized with sheep erythrocytes (SRBC) in complete Freund's adjuvant. Delayed hypersensitivity response (DHR) was assayed by the increase in foot pad swelling after the intrafoot pad injection of immune cells plus antigen. Cell-mediated cytotoxicity against SRBC was assayed by a microcytotoxicity test with sheep fibroblasts as target cells. Effector cells were antigen specific, sensitive to anti-theta serum plus complement (C), and insensitive to anti-Ig serum plus C. A nonrosette-forming (non-RFC) small lymphocyte effector T cell and a rosette-forming medium lymphocyte effector T cell were isolated by velocity sedimentation. The small lymphocyte non-RFC required a longer time than the medium lymphocyte RFC effector cell to produce maximum activity. Buoyant density failed to distinguish medium lymphocyte effector cells in DHR and in vitro cytotoxicity. (+info)
Limiting dilution analysis of helper T-cell function.
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Limiting dilution analysis has been applied to the study of T-cell 'helper' function in vitro. Using the microculture system one can estimate the numbers of (a) 'helper' T cells involved in specific collaboration with B cells and (b) those T cells which are able, on being activated by their specific antigen, to facilitate the response of B cells to another antigen. Such studies have enabled us to demonstrate that: (1) a single 'helper' T cell was able to activate a single B-cell precursor to detectable antibody production; (2) the 'helper' function of primed T cells was radio-resistant; (3) a minimal estimate of 'helper' frequencies could be obtained in defined cell populations; (4) nonspecific facilitation was directed towards virtually all available B cells of a given specificity if these were challenged with their appropriate particulate antigen; (5) the microculture system offers the opportunity to determine whether specific and non-specific T-cell 'helper' effects are a consequence of the activity of one T-cell type or of differenct subpopulations of T cells. (+info)
Post-coital sperm recovery and cryopreservation in the Sumatran rhinoceros (Dicerorhinus sumatrensis) and application to gamete rescue in the African black rhinoceros (Diceros bicornis).
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Sumatran rhinoceros (Dicerorhinus sumatrensis) sperm samples were collected from a post-copulatory female and characterized to determine their potential for sperm preservation and future use in artificial insemination. Five samples of acceptable quality from one male were used to compare the effect of two cryoprotectants (glycerol and dimethyl sulfoxide (DMSO)) and two post-thaw protocols (untreated and glass wool column) on sperm quality. The percentage of motile spermatozoa, sperm motility index (0-100) and sperm morphology were evaluated subjectively, and viability and acrosomal status were assessed using fluorescent markers. Evaluations of frozen-thawed spermatozoa were performed over a 6 h incubation interval. Post-coital semen samples (n = 5; 104.0 +/- 9.1 ml; 2.5 +/- 0.8 x 10(9) total spermatozoa; mean +/- SEM) exhibited a sperm motility index of 56.7 +/- 3.3, and contained 40.2 +/- 6.3%, 72.0 +/- 3.2% and 79.8 +/- 6.5% normal, viable and acrosome-intact spermatozoa, respectively. Glycerol and DMSO were equally effective as cryoprotectants and, regardless of post-thaw protocol, samples retained greater than 80% of all pre-freeze characteristic values. Processing semen samples through glass wool yielded higher quality samples, but only half the total number of motile spermatozoa compared with untreated samples. High values for pre-freeze sperm characteristics were also maintained after cryopreservation of epididymal spermatozoa from one black rhinoceros (Diceros bicornis) using the same protocol. In summary, Sumatran rhinoceros spermatozoa of moderate quality can be collected from post-copulatory females. Rhinoceros sperm samples show only slight reductions in quality after cryopreservation and thawing and have potential for use in artificial insemination. (+info)