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Author |
Heistermann, M.; Palme, R.; Ganswindt, A. |
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Title |
Comparison of different enzyme-immunoassays for assessment of adrenocortical activity in primates based on fecal analysis |
Type |
Journal Article |
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Year |
2006 |
Publication |
American journal of primatology |
Abbreviated Journal |
Am. J. Primatol. |
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Volume |
68 |
Issue |
3 |
Pages |
257-273 |
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Keywords |
11-Hydroxycorticosteroids/*analysis; Adrenocorticotropic Hormone/pharmacology; Anesthesia; Animals; Corticosterone/analysis; Feces/*chemistry; Glucocorticoids/*analysis; Haplorhini/*metabolism; Hydrocortisone/analysis; Hypothalamo-Hypophyseal System/drug effects/physiology; Immunoenzyme Techniques/*methods; Pituitary-Adrenal System/drug effects/physiology; Species Specificity |
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Abstract |
Most studies published to date that used fecal glucocorticoid measurements to assess adrenocortical activity in primate (and many nonprimate) species applied a specific cortisol or corticosterone assay. However, since these native glucocorticoids are virtually absent in the feces of most vertebrates, including primates, the validity of this approach has recently been questioned. Therefore, the overall aim of the present study was to assess the validity of four enzyme-immunoassays (EIAs) using antibodies raised against cortisol, corticosterone, and reduced cortisol metabolites (two group-specific antibodies) for assessing adrenocortical activity using fecal glucocorticoid metabolite (GCM) measurements in selected primate species (marmoset, long-tailed macaque, Barbary macaque, chimpanzee, and gorilla). Using physiological stimulation of the hypothalamo-pituitary-adrenocortical (HPA) axis by administering exogenous ACTH or anesthesia, we demonstrated that at least two assays detected the predicted increase in fecal GCM levels in response to treatment in each species. However, the magnitude of response varied between assays and species, and no one assay was applicable to all species. While the corticosterone assay generally was of only limited suitability for assessing glucocorticoid output, the specific cortisol assay was valuable for those species that (according to high-performance liquid chromatography (HPLC) analysis data) excreted clearly detectable amounts of authentic cortisol into the feces. In contrast, in species in which cortisol was virtually absent in the feces, group-specific assays provided a much stronger signal, and these assays also performed well in the other primate species tested (except the marmoset). Collectively, the data suggest that the reliability of a given fecal glucocorticoid assay in reflecting activity of the HPA axis in primates clearly depends on the species in question. Although to date there is no single assay system that can be used successfully across species, our data suggest that group-specific assays have a high potential for cross-species application. Nevertheless, regardless of which GC antibody is chosen, our study clearly reinforces the necessity of appropriately validating the respective assay system before it is used. |
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Department of Reproductive Biology, German Primate Center, Gottingen, Germany. mheiste@gwdg.de |
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0275-2565 |
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PMID:16477600 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
4078 |
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Author |
Aviad, A.D.; Houpt, J.B. |
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Title |
The molecular weight of therapeutic hyaluronan (sodium hyaluronate): how significant is it? |
Type |
Journal Article |
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Year |
1994 |
Publication |
The Journal of rheumatology |
Abbreviated Journal |
J Rheumatol |
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Volume |
21 |
Issue |
2 |
Pages |
297-301 |
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Keywords |
Animals; Horse Diseases/drug therapy; Horses; Humans; Hyaluronic Acid/*chemistry/*therapeutic use; Joint Diseases/*drug therapy/veterinary; Molecular Weight; Osteoarthritis/drug therapy/veterinary; Synovial Fluid/drug effects/physiology; Viscosity |
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Abstract |
Various molecular weight hyaluronic acid (HA) preparations have been injected into joints for the treatment of human and equine osteoarthritis. A therapeutic advantage has been claimed for commercial products with a molecular weight in the range found in normal synovial fluid (SF), compared to lower molecular weight products. But a correlation between molecular weight and efficacy is not borne out by an analysis of the available literature on clinical results. SF viscosity, HA concentration, HA molecular weight and rate of synthesis in joint disease. It is proposed that the beneficial effect of injected HA in joint disease may be due to pharmacological rather than to physical properties. |
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Rheumatic Disease Unit, Mount Sinai Hospital, University of Toronto, ON, Canada |
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0315-162X |
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PMID:8182640 |
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no |
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Call Number |
refbase @ user @ |
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35 |
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Author |
Turner, J.W.J.; Liu, I.K.; Kirkpatrick, J.F. |
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Title |
Remotely delivered immunocontraception in free-roaming feral burros (Equus asinus) |
Type |
Journal Article |
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Year |
1996 |
Publication |
Journal of reproduction and fertility |
Abbreviated Journal |
J Reprod Fertil |
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Volume |
107 |
Issue |
1 |
Pages |
31-35 |
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Keywords |
Animals; *Animals, Wild; Contraception, Immunologic/methods/*veterinary; *Equidae; Feces/chemistry; Female; Pregnancy; Pregnancy Tests; Swine; Zona Pellucida/immunology |
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Abstract |
Regulation of local overpopulations of free-roaming feral equids is in demand worldwide for ecological balance and habitat preservation. Contraceptive vaccines have proven effective in feral horses, which breed seasonally, but no data are available for equids such as the burro, which is reproductively active all year round. In the present study, 27 individually identified female feral burros (Equus asinus) roaming free in Virgin Islands National Park (St John, US Virgin Islands; Lesser Antilles) were remotely treated with pig zonae pellucidae (PZP) vaccine. Between January and May, 16 burros were darted with a 1 ml emulsion of PZP plus Freund's adjuvant. Ten to twelve months later each treated burro was given a single booster injection of PZP plus adjuvant to maintain contraception through a second year. Eleven adult untreated jennies served as controls. Beginning one year after initial vaccination, these burros were monitored for pregnancy and foal production. Collection of data to determine treatment effect was not begun until 12 months after initial treatment to ensure that pregnancies existing before vaccination were not included. Pregnancy was assessed using previously validated methods for steroid metabolite measurement in fresh faecal samples. None of the PZP-treated burros produced foals between 0 and 12 months after the last inoculation. One PZP-treated burro tested positive for pregnancy at 10 months after the final inoculation. During this same period, six of 11 untreated burros tested pregnancy-positive, and four were observed with foals. There was no difference in pregnancy rates among treated, control and randomly sampled jennies between 12 and 24 months after the last inoculation. The results demonstrate that, in free-roaming feral burros that are reproductively active all year round: (1) burros can be accessed for remotely delivered PZP vaccination; (2) PZP contraception is effective; (3) PZP contraception is reversible; and (4) pregnancy can be reliably detected by faecal steroid analysis. |
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Department of Physiology and Molecular Medicine, Medical College of Ohio, Toledo 43699, USA |
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0022-4251 |
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Notes |
PMID:8699431 |
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no |
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Call Number |
refbase @ user @ |
Serial |
144 |
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Author |
Husted, L.; Andersen, M.S.; Borggaard, O.K.; Houe, H.; Olsen, S.N. |
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Title |
Risk factors for faecal sand excretion in Icelandic horses |
Type |
Journal Article |
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Year |
2005 |
Publication |
Equine Veterinary Journal |
Abbreviated Journal |
Equine Vet J |
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Volume |
37 |
Issue |
4 |
Pages |
351-355 |
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Keywords |
Animal Feed; Animal Husbandry/methods; Animals; Denmark; Feces/*chemistry; Female; Gastrointestinal Diseases/epidemiology/etiology/prevention & control/veterinary; Horse Diseases/epidemiology/etiology/prevention & control; Horses/*metabolism; Logistic Models; Male; Pilot Projects; *Poaceae/growth & development; Risk Factors; Silicon Dioxide/administration & dosage/adverse effects/*analysis; Soil/*analysis |
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Abstract |
REASONS FOR PERFORMING STUDY: Sandy soil is often mentioned as a risk factor in the development of sand-related gastrointestinal disease (SGID) in the horse. There are other variables, but few studies confirm any of these. OBJECTIVE: To investigate soil type, pasture quality, feeding practice in the paddock, age, sex and body condition score as risk factors for sand intake in the horse. METHODS: Faeces were collected from 211 Icelandic horses on 19 different studs in Denmark together with soil samples and other potential risk factors. Sand content in faeces determined by a sand sedimentation test was interpreted as evidence of sand intake. Soil types were identified by soil analysis and significance of the data was tested using logistic analysis. RESULTS: Of horses included in the study, 56.4% showed sand in the faeces and 5.7% had more than 5 mm sand as quantified by the rectal sleeve sedimentation test. Soil type had no significant effect when tested as main effect, but there was interaction between soil type and pasture quality. Significant interactions were also found between paddock feeding practice and pasture quality. CONCLUSION: To evaluate the risk of sand intake it is important to consider 3 variables: soil type, pasture quality and feeding practice. Pasture quality was identified as a risk factor of both short and long grass in combination with sandy soil, while clay soil had the lowest risk in these combinations. Feeding practice in the paddock revealed feeding directly on the ground to be a risk factor when there was short (1-5 cm) or no grass. Also, no feeding outdoors increased the risk on pastures with short grass, while this had no effect in paddocks with no grass. More than 50% of all horses investigated in this study had sand in the faeces. POTENTIAL RELEVANCE: The identification of risk factors is an important step towards prevention of SGID. Further research is necessary to determine why some horses exhibit more than 5 mm sand in the sedimentation test and whether this is correlated with geophagic behaviour. |
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Department of Large Animal Sciences, The Royal Veterinary and Agricultural University, Dyrlaegevej 88, DK-1870 Frederiksberg, Denmark |
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0425-1644 |
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Notes |
PMID:16028626 |
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no |
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Call Number |
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Serial |
1888 |
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Author |
McCutcheon, L.J.; Geor, R.J. |
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Title |
Influence of training on sweating responses during submaximal exercise in horses |
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Journal Article |
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Year |
2000 |
Publication |
Journal of Applied Physiology (Bethesda, Md. : 1985) |
Abbreviated Journal |
J Appl Physiol |
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Volume |
89 |
Issue |
6 |
Pages |
2463-2471 |
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Keywords |
Animals; Body Fluids/metabolism; Body Temperature; Body Weight; Environment; Female; Horses/*physiology; Ions; Male; Motor Activity/*physiology; Oxygen Consumption; Physical Conditioning, Animal/*physiology; Sweat/chemistry; Sweating/*physiology; Time Factors |
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Sweating responses were examined in five horses during a standardized exercise test (SET) in hot conditions (32-34 degrees C, 45-55% relative humidity) during 8 wk of exercise training (5 days/wk) in moderate conditions (19-21 degrees C, 45-55% relative humidity). SETs consisting of 7 km at 50% maximal O(2) consumption, determined 1 wk before training day (TD) 0, were completed on a treadmill set at a 6 degrees incline on TD0, 14, 28, 42, and 56. Mean maximal O(2) consumption, measured 2 days before each SET, increased 19% [TD0 to 42: 135 +/- 5 (SE) to 161 +/- 4 ml. kg(-1). min(-1)]. Peak sweating rate (SR) during exercise increased on TD14, 28, 42, and 56 compared with TD0, whereas SRs and sweat losses in recovery decreased by TD28. By TD56, end-exercise rectal and pulmonary artery temperature decreased by 0.9 +/- 0.1 and 1.2 +/- 0.1 degrees C, respectively, and mean change in body mass during the SET decreased by 23% (TD0: 10.1 +/- 0.9; TD56: 7.7 +/- 0.3 kg). Sweat Na(+) concentration during exercise decreased, whereas sweat K(+) concentration increased, and values for Cl(-) concentration in sweat were unchanged. Moderate-intensity training in cool conditions resulted in a 1.6-fold increase in sweating sensitivity evident by 4 wk and a 0.7 +/- 0.1 degrees C decrease in sweating threshold after 8 wk during exercise in hot, dry conditions. Altered sweating responses contributed to improved heat dissipation during exercise and a lower end-exercise core temperature. Despite higher SRs for a given core temperature during exercise, decreases in recovery SRs result in an overall reduction in sweat fluid losses but no change in total sweat ion losses after training. |
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Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada N1G 2W1. jmccutch@uoguelph.ca |
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8750-7587 |
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Notes |
PMID:11090603 |
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no |
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Call Number |
refbase @ user @ |
Serial |
1922 |
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Author |
Traversa, D.; Giangaspero, A.; Iorio, R.; Otranto, D.; Paoletti, B.; Gasser, R.B. |
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Title |
Semi-nested PCR for the specific detection of Habronema microstoma or Habronema muscae DNA in horse faeces |
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Journal Article |
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Year |
2004 |
Publication |
Parasitology |
Abbreviated Journal |
Parasitology |
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Volume |
129 |
Issue |
Pt 6 |
Pages |
733-739 |
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Keywords |
Animals; DNA, Helminth/*analysis; DNA, Ribosomal Spacer/*chemistry; Feces/*chemistry; Female; Horse Diseases/*diagnosis/parasitology; Horses; Male; Polymerase Chain Reaction/*methods; Species Specificity; Spirurida Infections/diagnosis/*veterinary; Spiruroidea/*genetics |
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Habronema microstoma and Habronema muscae (Spirurida: Habronematidae) are parasitic nematodes which infect the stomach and/or skin of equids. The accurate diagnosis of gastric habronemosis is central to studying its epidemiology, but data on its distribution and prevalence are lacking, mainly due to the limitations of clinical and coprological diagnosis in live horses. To overcome this constraint, a two-step, semi-nested PCR-based assay was validated (utilizing genetic markers in the nuclear ribosomal DNA) for the specific amplification of H. microstoma or H. muscae DNA from the faeces from horses (n = 46) whose gastrointestinal parasite status had been determined at autopsy and whose faeces were examined previously using a conventional parasitological approach. Of these horses examined at autopsy, some harboured adults of either H. microstoma (n= 19) or H. muscae (n =4), and others (n = 7) harboured both species. Most of them were also infected with other parasites, including strongylid nematodes (subfamilies Cyathostominae and Strongylinae), bots and/or cestodes; there was no evidence of metazoan parasites in 2 horses. Larvated spirurid eggs were detected in the faeces of 1 of the 30 horses (3.3 %) shown to be infected with Habronema at autopsy. For this set of 46 samples, the PCR assay achieved a diagnostic specificity of 100 % and a sensitivity of approximately 97 % (being able to specifically detect as little as approximately 0.02 fg of Habronema DNA). The specificity of the assay was also tested using a panel of control DNA samples representing horse, the gastric spirurid Draschia megastoma and 26 other species of parasites from the alimentary tract of the horse. H. microstoma, H. muscae and D. megastoma could be readily differentiated from one another based on the sizes of their specific amplicons in the PCR. The results of this study showed that the performance of the PCR for the diagnosis of gastric habronemosis was similar to that of autopsy but substantially better than the traditional coprological examination procedure used. The ability to specifically diagnose gastric habronemosis in equids should have important implications for investigating the epidemiology and ecology of H. microstoma and H. muscae. |
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Department of Biomedical Comparative Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy. traversa@unite.it |
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0031-1820 |
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PMID:15648696 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2631 |
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Author |
Selby, L.A.; Marienfeld, C.J.; Pierce, J.O. |
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Title |
The effects of trace elements on human and animal health |
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Journal Article |
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Year |
1970 |
Publication |
Journal of the American Veterinary Medical Association |
Abbreviated Journal |
J Am Vet Med Assoc |
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Volume |
157 |
Issue |
11 |
Pages |
1800-1808 |
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Keywords |
Anemia, Hypochromic/veterinary; Animal Nutrition Physiology; Animals; Artiodactyla/*physiology; Chemistry; Cobalt/analysis/metabolism; Copper/analysis/metabolism; Deficiency Diseases/veterinary; Dogs/*physiology; Ecology; Horses/*physiology; Humans; Iodine/analysis/metabolism; Iron/analysis/metabolism; Manganese/analysis/metabolism; Nutritional Requirements; Selenium/metabolism; Trace Elements/*metabolism; Zinc/analysis/metabolism |
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0003-1488 |
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PMID:4922190 |
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Equine Behaviour @ team @ |
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2733 |
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Author |
Pere, M.C. |
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Title |
Maternal and fetal blood levels of glucose, lactate, fructose, and insulin in the conscious pig |
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Journal Article |
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Year |
1995 |
Publication |
Journal of Animal Science |
Abbreviated Journal |
J. Anim Sci. |
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73 |
Issue |
10 |
Pages |
2994-2999 |
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Keywords |
Animals; Blood Glucose/*analysis; Catheterization/methods/veterinary; Consciousness/physiology; Female; Fetal Blood/*chemistry; Fructose/analysis/*blood; Insulin/analysis/*blood; Lactates/analysis/*blood; Pregnancy; Swine/*blood/physiology |
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Abstract |
To study nutrition and metabolism in the fetal pig, a chronic catheterization method was developed that allows blood sampling in arteries and veins, at both the umbilical and uterine sources, in the conscious, unstressed animal. A catheter was inserted in the fetal aorta through a femoral artery, and another one was introduced in the umbilical vein. A catheter was put in a femoral artery of the sow so that its end was in the abdominal aorta. A fourth catheter was placed in a uterine vein draining the fetoplacental unit studied. This procedure was applied to 18 Large White primiparous sows at 99 d of gestation. Blood samples were drawn simultaneously using the four catheters before a meal at 103 d of pregnancy, and glucose, insulin, lactate, and fructose were determinated. Glycemia was 2.5 times higher in the sow than in the fetus. The extraction coefficient of glucose by the fetus amounted to 14% of the umbilical supply. The insulin level in the fetal pig was very low ( < 5 microU/mL). Lactate and fructose seemed to originate from the placenta. Blood lactate was 2.6 times lower in the sow than in the fetus, and its extraction coefficient by the fetus amounted to 8%. Fructose in the fetal blood was 2.3 times higher than that of glucose. Fructose was not utilized by the pig fetus. The present results obtained in the fetal pig are comparable to the conclusions drawn from studies with other species. |
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Station de Recherches Porcines, Institut National de la Recherche Agronomique, Saint-Gilles, France |
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0021-8812 |
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PMID:8617670 |
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no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
2751 |
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Author |
Abbruzzetti, S.; Viappiani, C.; Sinibaldi, F.; Santucci, R. |
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Title |
Kinetics of histidine dissociation from the heme Fe(III) in N-fragment (residues 1-56) of cytochrome c |
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Journal Article |
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Year |
2004 |
Publication |
The Protein Journal |
Abbreviated Journal |
Protein J |
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Volume |
23 |
Issue |
8 |
Pages |
519-527 |
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Keywords |
Animals; Cytochromes c/*chemistry; Enzyme Activation; Histidine/*chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; Lasers; Ligands; Peptide Mapping; Photolysis; Spectrophotometry |
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Abstract |
We have here investigated the dissociation kinetics of the His side chains axially ligated to the heme-iron in the ferric (1-56 residues) N-fragment of horse cyt c. The ligand deligation induced by acidic pH-jump occurs as a biexponential process with different pre-exponential factors, consistent with a structural heterogeneity in solution and the presence of two differently coordinated species. In analogy with GuHCl-denatured cyt c, our data indicate the presence in solution of two ferric forms of the N-fragment characterized by bis-His coordination, as summarized in the following scheme: His18-Fe(III)-His26 <==> His18-Fe(III)-His33. We have found that the pre-exponential factors depend on the extent of the pH-jump. This may be correlated with the different pKa values shown by His26 and His33; due to steric factors, His26 binds to the heme-Fe(III) less strongly than His33, as recently shown by studies on denatured cyt c. Interestingly, the two lifetimes are affected by temperature but not by the extent of the pH-jump. The lower pKa for the deligation reaction required the use of an improved laser pH-jump setup, capable of inducing changes in H+ concentration as large as 1 mM after the end of the laser pulse. For the ferric N-fragment, close activation entropy values have been determined for the two histidines coordinated to the iron; this result significantly differs from that for GuHCl-denatured cyt c, where largely different values of activation entropy were calculated. This underlines the role played by the missing segment (residues 57-104) peptide chain in discriminating deligation of the “nonnative” His from the sixth coordination position of the metal. |
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Dipartimento di Fisica, Universita degli Studi di Parma, Parco Area delle Scienze 7/A 43100 Parma, Italy |
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ISSN |
1572-3887 |
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Notes |
PMID:15648974 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3770 |
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Author |
Hirota, S.; Suzuki, M.; Watanabe, Y. |
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Title |
Hydrophobic effect of trityrosine on heme ligand exchange during folding of cytochrome c |
Type |
Journal Article |
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Year |
2004 |
Publication |
Biochemical and Biophysical Research Communications |
Abbreviated Journal |
Biochem Biophys Res Commun |
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Volume |
314 |
Issue |
2 |
Pages |
452-458 |
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Keywords |
Amino Acids/chemistry; Animals; Cytochromes c/*chemistry; Heme/*chemistry; Histidine/chemistry; Horses; Hydrogen-Ion Concentration; Kinetics; Ligands; Myocardium/chemistry; Peptides/chemistry; Protein Folding; Spectrophotometry; Spectrum Analysis, Raman; Tyrosine/*analogs & derivatives/*chemistry |
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Abstract |
Effect of a hydrophobic peptide on folding of oxidized cytochrome c (cyt c) is studied with trityrosine. Folding of cyt c was initiated by pH jump from 2.3 (acid-unfolded) to 4.2 (folded). The Soret band of the 2-ms transient absorption spectrum during folding decreased its intensity and red-shifted from 397 to 400 nm by interaction with trityrosine, whereas tyrosinol caused no significant effect. The change in the transient absorption spectrum by interaction with trityrosine was similar to that obtained with 100 mM imidazole, which showed that the population of the intermediate His/His coordinated species increased during folding of cyt c by interaction with trityrosine. The absorption change was biphasic, the fast phase (82+/-9s(-1)) corresponding to the transition from the His/H(2)O to the His/Met coordinated species, whereas the slow phase (24+/-3s(-1)) from His/His to His/Met. By addition of trityrosine, the relative ratio of the slow phase increased, due to increase of the His/His species at the initial stage of folding. According to the resonance Raman spectra of cyt c, the high-spin 6-coordinate and low-spin 6-coordinate species were dominated at pH 2.3 and 4.2, respectively, and these species were not affected by addition of trityrosine. These results demonstrated that the His/His species increased by interaction with trityrosine at the initial stage of cyt c folding, whereas the heme coordination structure was not affected by trityrosine when the protein was completely unfolded or folded. Hydrophobic peptides thus may be useful to study the effects of hydrophobic interactions on protein folding. |
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Address |
Department of Physical Chemistry, Kyoto Pharmaceutical University, Yamashina-ku, 607-8414 Kyoto, Japan. hirota@mb.kyoto-phu.ac.jp |
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Language |
English |
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Original Title |
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Abbreviated Series Title |
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Edition |
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ISSN |
0006-291X |
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Notes |
PMID:14733927 |
Approved |
no |
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Call Number |
Equine Behaviour @ team @ |
Serial |
3777 |
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