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Sharon T Pochron - One of the best experts on this subject based on the ideXlab platform.
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can concurrent speed and directness of travel indicate purposeful encounter in the yellow Baboons papio hamadryas cynocephalus of ruaha national park tanzania
International Journal of Primatology, 2001Co-Authors: Sharon T PochronAbstract:I used components of Baboon foraging behavior (concurrent fast and direct travel) to categorize core dry-season foods as purposefully or randomly encountered. I then compared the categorized foods to published, a priori predictions for core dry-season foods. Using focal-animal techniques on 6 males from two Baboon troops, I collected precise locational data with a differentially corrected Global Positioning System (GPS) over 6 mo. The data analysis yielded the speed and directness of Baboon travel between a food-handling event and a prior location. To distinguish purposefully encountered foods from randomly encountered foods, I calculated the average speed and the average observed deviation from straight-line travel exhibited to each resource type. A linear regression describes the relationship between these variables for each resource type. Baboons demonstrate both relatively high speeds and direct travel towards 3 food types: Combretum obovatum, impala, and baobab trees. Baboons were hypothesized a priori to encounter these resources purposefully. Baboons were also hypothesized a priori to encounter corms and perhaps Commiphora paniculatum purposefully, however, they travel neither quickly nor directly to these resources. I interpret this finding in terms of the costs accrued by traveling quickly and directly to fall-back resources. I discuss the ability of concurrent speed and directness to distinguish purposefully encountered foods from randomly encountered foods.
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sun avoidance in the yellow Baboons papio cynocephalus cynocephalus of ruaha national park tanzania variations with season behavior and weather
International Journal of Biometeorology, 2000Co-Authors: Sharon T PochronAbstract:Do free-ranging Baboons avoid traveling towards the sun? Sun avoidance, in addition to resource and predator locations, may influence troop movement and non-random use of the home range. This paper investigates how sun avoidance, as measured by facial exposure to sunlight, influences directional choices. It hypothesizes that Baboons should avoid the sun in the hot, dry season and show indifference to it in the cool, lush season. This paper also hypothesizes that Baboons employ sun-avoidance behaviors more while they forage or travel to resting sites than when they travel to foraging sites or engage in active social behaviors; lastly this paper hypothesizes that sun altitude, temperature, humidity, and cloud cover influence sun-avoidance behavior. Using focal-animal techniques on 21 males from free-ranging Baboon troops, I collected locational data, accurate to within 1.6 m, over 15 months. I calculated the difference between Baboon bearings and the sun’s azimuth in angular degrees. Both linear and circular statistics indicate that Baboons put significantly (P<0.01) more than 90° between their bearing and the sun’s azimuth under certain conditions. Contrary to hypotheses based on the detrimental effects of insolation, Baboons in the cool, lush season avoid the sun, while Baboons in the hot, dry season do not. In the lush season, the extent to which Baboons avoid the sun does not depend on their other behaviors. Dry-season Baboons demonstrate stronger sun avoidance while resting than when engaged in other behaviors. Finally, in the dry season, temperature drives sun avoidance; humidity drives it in the lush season.
David K. C. Cooper - One of the best experts on this subject based on the ideXlab platform.
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persistence of indirect but not direct t cell xenoresponses in Baboon recipients of pig cell and organ transplants
American Journal of Transplantation, 2016Co-Authors: L Buhler, David K. C. Cooper, Aseda Tena, Ben Minwoo Illigens, O Nadazdin, David H Sachs, Gilles BenichouAbstract:: We investigated the contributions of direct and indirect T cell antigen recognition pathways to the immune response to porcine antigens in naive Baboons and Baboon recipients of pig xenografts. In naive Baboons, in vitro culture of peripheral blood T cells with intact pig cells (direct xenorecognition pathway) or pig cell sonicates and Baboon antigen-presenting cells (indirect xenorecognition pathway) induced the activation and expansion of xenoreactive T cells producing proinflammatory cytokines, interleukin-2 and interferon-γ. Primary indirect xenoresponses were mediated by preexisting memory T cells, whose presence is not typically observed in primary alloresponses. Next, Baboons were conditioned with a nonmyeloablative regimen before short-term immunosuppression and transplantation of xenogeneic peripheral blood progenitor cells and a kidney, heart, or pancreatic islets from a miniature swine. All transplants were rejected acutely within 30 days after their placement. Posttransplantation, we observed an inhibition of the direct xenoresponse but a significant expansion of indirectly activated proinflammatory T cells. These results suggest that additional treatment to suppress indirect T cell immunity in primates may be required to achieve tolerance of pig xenografts through hematopoietic chimerism.
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investigation of potential carbohydrate antigen targets for human and Baboon antibodies
Xenotransplantation, 2010Co-Authors: Mohamed Ezzelarab, M Awwad, Nicolai V Bovin, Hidetaka Hara, Cassandra Long, Koji Tomiyama, David Ayares, David K. C. CooperAbstract:Yeh P, Ezzelarab M, Bovin N, Hara H, Long C, Tomiyama K, Sun F, Ayares D, Awwad M, Cooper DKC. Investigation of potential carbohydrate antigen targets for human and Baboon antibodies. Xenotransplantation 2010; 17: 197–206. © 2010 John Wiley & Sons A/S. Abstract: Background: The continued presence of a primate antibody-mediated response to cells and organs from α1,3-galactosyltransferase gene-knockout (GTKO) pigs indicates that there may be antigens other than Galα1,3Gal (αGal) against which primates have xenoreactive antibodies. Human and Baboon sera were tested for reactivity against a panel of saccharides that might be potential antigen targets for natural anti-non-αGal antibodies. Methods: Human sera (n = 16) and Baboon sera (n = 15) of all ABO blood types were tested using an enzyme-linked immunoadsorbent assay for binding of IgM and IgG to a panel of synthetic polyacrylamide-linked saccharides (n = 15). Human sera were also tested after adsorption on αGal immunoaffinity beads. Sera from healthy wild-type (WT, n = 6) and GTKO (n = 6) pigs and from Baboons (n = 4) sensitized to GTKO pig organ or artery transplants (of blood type O) were also tested. Forssman antigen expression on Baboon and pig tissues was investigated by immunohistochemistry. Results: Both human and Baboon sera showed high IgM and IgG binding to αGal saccharides, α-lactosamine, and Forssman disaccharide. Human sera also demonstrated modest binding to N-glycolylneuraminic acid (Neu5Gc). When human sera were adsorbed on αGal oligosaccharides, there was a reduction in binding to αGal and α-lactosamine, but not to Forssman. WT and GTKO pig sera showed high binding to Forssman, and GTKO pig sera showed high binding to αGal saccharides. Baboon sera sensitized to GTKO pigs showed no significant increased binding to any specific saccharide. Staining for Forssman was negative on Baboon and pig tissues. Conclusions: We were unable to identify definitively any saccharides from the selected panel that may be targets for primate anti-non-αGal antibodies. The high level of anti-Forssman antibodies in humans, Baboons, and pigs, and the absence of Forssman expression on pig tissues, suggest that the Forssman antigen does not play a role in the primate immune response to pigs.
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Extended coagulation profiles of healthy Baboons and of Baboons rejecting GT-KO pig heart grafts.
Xenotransplantation, 2006Co-Authors: Mohamed Ezzelarab, David K. C. Cooper, Andrea Cortese-hassett, Mark H. YazerAbstract:Abstract: Introduction: Derangements of coagulation, e.g. thrombotic microangiopathy (TM) and disseminated intravascular coagulation (DIC), limit the success of pig-to-Baboon organ transplantation. Studies have investigated the coagulation profile in Baboons post-xenotransplantation (XTx), but an extended coagulation profile of healthy Baboons pre-XTx has not been reported. Methods: Blood was drawn from nine healthy male Baboons (approximate age 5 yr, mean weight 15 kg) that had not undergone any prior surgical or therapeutic procedures. An extended coagulation profile, consisting of markers of thrombin activation, fibrinolysis, endothelial activation, the protein C pathway, and overall reactive state, was investigated by a reference coagulation laboratory, using tests for human plasma. The mean value ± SD was calculated for 18 parameters (analytes); values outside of the mean ± 2 SD were excluded. Three Baboons subsequently underwent transplantation with hearts from GT-KO pigs, and received either no therapy (B24603), CVF (B25003), or CVF + leflunomide (B24903), and their extended coagulation parameters were followed. Results: For 14 of the 18 analytes, the human reference range reflected the coagulation status of healthy Baboons. Exceptions included thrombin/antithrombin complex and fibrinopeptide A, which were elevated compared with the human reference range, while plasminogen activity was lower. The human assay failed to detect Baboon plasminogen activator inhibitor-1. Immediately after GT-KO pig heart transplantation, the untreated B24603 demonstrated a coagulation profile consistent with its postoperative clinical status; DIC was not apparent, and the heart was electively excised within 2.5 h. In B25003 and B24903, that rejected their grafts on days 8 and 12, respectively, the coagulation profile showed evidence of DIC, particularly in B24903, which was clinically coagulopathic by this time. Conclusions: (i) The human reference range of extended coagulation parameters forms a basis for studies in Baboons, with a few exceptions. (ii) Antibody-mediated rejection of GT-KO pig hearts in Baboons can be associated with laboratory and clinical evidence of DIC.
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Absence of humoral and cellular alloreactivity in Baboons sensitized to pig antigens.
Xenotransplantation, 2003Co-Authors: R. M. Baertschiger, Derek D. Prabharasuth, Kenji Kuwaki, David K. C. CooperAbstract:AIM: to study whether sensitization to pig antigens results in humoral and/or cellular sensitization to alloantigens in Baboons, and thus increases the risks of organ allotransplantation after xenotransplantation. Serum from Baboons that were naive (n = 4), sensitized to Gal alpha 1,3Gal (Gal) antigens (n = 2), or sensitized to Gal + non-Gal pig antigens (n = 2) were tested by flow cytometry for the presence of immunoglobulin G (IgG) and IgM antibodies that bind to pig or Baboon peripheral blood mononuclear cells (PBMC). Two allosensitized Baboons were used as positive controls. The same 10 sera were tested in a complement-mediated cytotoxicity assay to detect cytotoxic antibodies against pig, allo and self-PBMC. The T-cell responses of the same Baboons to allogeneic and pig PBMC stimulators in mixed lymphocyte reaction (MLR) were studied. All Baboon sera contained cytotoxic antibodies that bound to pig PBMC. Binding and cytotoxicity were higher in xenosensitized Baboons, particularly in those sensitized to Gal + non-Gal antigens (P < 0.001). None of the naive or xenosensitized Baboon sera bound to Baboon PBMC. Serum from allosensitized Baboons showed anti-Baboon IgG and IgM binding, but there was no increase in binding to pig PBMC or in cytotoxicity to pig cells. The MLR response to pig stimulators in Baboons sensitized to non-Gal pig antigens was greater than that of naive or Gal-sensitized Baboons (P < 0.001), but there was no increase in the response to Baboon cells. In Baboons, no in vitro evidence that a previous pig xenograft might endanger the outcome of a subsequent allograft was documented.
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pig kidney transplantation in Baboons treated intravenously with a bovine serum albumin galα1 3gal conjugate
Xenotransplantation, 2003Co-Authors: Bernd Gollackner, L Buhler, David H Sachs, C Knosalla, Stuart L Houser, Shamila Mauiyyedi, Tatsuo Kawai, Michael Duggan, M Awwad, David K. C. CooperAbstract:The maintenance of depletion of antibody (Ab) reactive with Galalpha1-3Gal (Gal) on pig vascular endothelial cells by the intravenous (i.v.) infusion of a synthetic Gal conjugate has been proposed as a means of delaying Ab-mediated rejection of transplanted pig organs in primates. We have therefore studied the effect of the continuous i.v. infusion of bovine serum albumin conjugated to multiple synthetic Gal type 6 oligosaccharides (BSA-Gal) on anti-Gal Ab levels and on graft survival in Baboons undergoing pig kidney transplantation. Group 1 Baboons (n=3) underwent extracorporeal immunoadsorption of anti-Gal Ab, a cyclophosphamide (CPP)-based immunosuppressive regimen, and a non-transgenic pig kidney transplant. Group 2 (n=2) were treated identically to Group 1 but, in addition, received a continuous i.v. infusion of BSA-Gal. Group 3 (n=2) were treated identically to Group 2, but without CPP. A single Baboon (Group 4) underwent extracorporeal immunoadsorption, a CPP-based regimen, and continuous i.v. BSA-Gal therapy for 28 days, but did not receive a pig kidney transplant. Two of the transplanted pig kidneys in Group 1 were excised on post transplant days 7 and 13 for a rejected ureter, and disseminated intravascular coagulation (DIC), respectively. The third Baboon died of sepsis on day 6. All transplanted ureters and kidneys showed some histopathologic features of acute humoral xenograft rejection. Group 2 Baboons were euthanized on days 8 and 11, respectively, for liver failure. At autopsy, there were histopathological features of widespread liver necrosis, but the pig kidneys and ureters showed no features of rejection. The pig kidneys in Group 3 Baboons were excised for renal vein thrombosis (day 9) and DIC (day 12); there was no histological signs of rejection in the pig kidneys or ureter, although there were focal areas of modest liver injury in one Baboon on biopsy. The single Group 4 Baboon showed no biochemical or histological features of liver injury. Anti-Gal Ab levels returned in Group 1, but were maintained at negligible levels in the Baboons in Groups 2 to 4 that received BSA-Gal therapy. Continuous i.v. therapy with BSA-Gal is largely successful in maintaining depletion of circulating anti-Gal antibodies and in preventing or delaying Ab deposition and acute humoral xenograft rejection in porcine grafts, but may be associated with liver injury when administered in the presence of a pig kidney transplant and CPP therapy. The mechanism of the hepatic injury remains uncertain.
Robert E. Ferrell - One of the best experts on this subject based on the ideXlab platform.
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association of slc34a2 variation and sodium lithium countertransport activity in humans and Baboons
American Journal of Hypertension, 2009Co-Authors: Xiaojing Zheng, Alanna C Morrison, Stephen T Turner, Candace M Kammerer, Robert E. FerrellAbstract:BACKGROUND Sodium-lithium countertransport (SLC) activity, an intermediate phenotype of essential hypertension, has been linked to a region of Baboon chromosome 5, homologous to human chromosome 4p. Human SLC34A2, located at chromosome 4p15.1 -p15.3, is a positional candidate gene for SLC.The specific aim of this study was to identify genetic variants of the SLC34A2 gene in both Baboon and human, and to examine the relationship of these polymorphisms with SLC activity and blood pressure. METHODS Single-nucleotide polymorphism (SNP) was identified by sequencing the SLC34A2 gene in 24 Baboon founders and 94 unrelated individuals. All tag SNPs in SLC34A2 were genotyped in 1,856 individuals from 252 pedigrees of mixed European ancestry. Three SNPs in Baboon were genotyped in 634 Baboons comprising 11 pedigrees. RESULTS In human, one SNP (rs12501856) was found to be significantly associated with SLC individually, though it did not pass multiple testing correction; however, haplotype 2 containing allele C of SNP rs12501856 showed strong evidence of association with SLC (P= 0.0037) after multiple comparison adjustment.This haplotype was also marginally associated with diastolic blood pressure and systolic blood pressure. This finding was confirmed in Baboons, where a highly significant association was detected between SLC and Baboon SNP Asn136Asn (P = 0.0001). However, the associated SNP did not account for the linkage signal on Baboon chromosome 5. CONCLUSIONS Consistent results in two different species imply that SLC34A2 is associated with SLC activity and blood pressure.
Xiaojing Zheng - One of the best experts on this subject based on the ideXlab platform.
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association of slc34a2 variation and sodium lithium countertransport activity in humans and Baboons
American Journal of Hypertension, 2009Co-Authors: Xiaojing Zheng, Alanna C Morrison, Stephen T Turner, Candace M Kammerer, Robert E. FerrellAbstract:BACKGROUND Sodium-lithium countertransport (SLC) activity, an intermediate phenotype of essential hypertension, has been linked to a region of Baboon chromosome 5, homologous to human chromosome 4p. Human SLC34A2, located at chromosome 4p15.1 -p15.3, is a positional candidate gene for SLC.The specific aim of this study was to identify genetic variants of the SLC34A2 gene in both Baboon and human, and to examine the relationship of these polymorphisms with SLC activity and blood pressure. METHODS Single-nucleotide polymorphism (SNP) was identified by sequencing the SLC34A2 gene in 24 Baboon founders and 94 unrelated individuals. All tag SNPs in SLC34A2 were genotyped in 1,856 individuals from 252 pedigrees of mixed European ancestry. Three SNPs in Baboon were genotyped in 634 Baboons comprising 11 pedigrees. RESULTS In human, one SNP (rs12501856) was found to be significantly associated with SLC individually, though it did not pass multiple testing correction; however, haplotype 2 containing allele C of SNP rs12501856 showed strong evidence of association with SLC (P= 0.0037) after multiple comparison adjustment.This haplotype was also marginally associated with diastolic blood pressure and systolic blood pressure. This finding was confirmed in Baboons, where a highly significant association was detected between SLC and Baboon SNP Asn136Asn (P = 0.0001). However, the associated SNP did not account for the linkage signal on Baboon chromosome 5. CONCLUSIONS Consistent results in two different species imply that SLC34A2 is associated with SLC activity and blood pressure.
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SEARCHING FOR GENETIC DETERMINANTS FOR SODIUM LITHIUM COUNTERTRANSPORT, AN INTERMEDIATE TRAIT FOR ESSENTIAL HYPERTENSION
2007Co-Authors: Xiaojing ZhengAbstract:Essential hypertension (EH) is a major risk factor for cardiovascular disorders, the leading cause of death in the United States. Given its great public health impact, it is crucial to understand the genetic basis of EH. EH is highly heterogeneous and to use an intermediate phenotype of EH, sodium lithium countertransport (SLC), will provide substantial advantage for disease genes discovery. We proposed two approaches to explore the genes for SLC.The first study examined the relationship between SLC and a positional candidate gene, SLC34A2, which is linked to SLC in Baboon. We sequenced gene SLC34A2 in Baboon and human. Strong homology was established in exonic organization and sequence between human and Baboon SLC34A2 genes and extensive variation in both species was identified. Association studies between SLC and SLC34A2 were carried out in 1856 RFHS phase II individuals and 634 Baboons. Significant association of SLC with human SNP rs3775909 (p=0.03) in SLC34A2 and haplotype block 2 (p
Gene B. Hubbard - One of the best experts on this subject based on the ideXlab platform.
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Natural pathology of the Baboon (Papio spp.).
Journal of Medical Primatology, 2011Co-Authors: Yugendar R. Bommineni, Edward J. Dick, Adinarayana R. Malapati, Michael A. Owston, Gene B. HubbardAbstract:The Baboon is an increasingly important non-human primate model used in biomedical research. Accurate, extensive information about the natural pathology of the Baboon is required for many aspects of biomedical research [59]. Baboons are currently studied for nutrition, fetal development and loss, endometriosis, infectious diseases, drug abuse, xenotransplantation, and epilepsy [7, 50, 53, 57–59, 61]. Veterinarians and researchers can use the frequency of different diseases to aid in diagnosis, make decisions on prognosis, foresee the possible interference with specific experimental procedures, and determine whether the Baboon is an appropriate model [14, 17]. Numerous articles have been published on individual diseases in Baboons [59], but the frequency of spontaneously occurring disease in Baboons is not generally available in the literature. To our knowledge, only two previous studies looked at the prevalence of disease in Baboons; both were conducted over 35 years ago and had relatively few numbers of animals. One evaluated 100 Baboons directly from the wild [31]; the other study evaluated 105 captive Baboons [26]. We document the spontaneous pathology over a 20-year period in the Southwest National Primate Research Center at the Southwest Foundation for Biomedical Research (SFBR) Baboon colony. The analysis of this information will further define the Baboon as an animal model and give insight into the natural pathology of the Baboon.
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Trichobezoars in Baboons
Journal of Medical Primatology, 2009Co-Authors: Diana C.p. Mejido, Edward J. Dick, R.m. Sharp, Priscilla C. Williams, Márcia Cristina Ribeiro Andrade, C.d. Dicarlo, Gene B. HubbardAbstract:Background There is little information available concerning trichobezoars in the non-human primate literature. Methods We evaluated 118 cases of trichobezoar in Baboons over a 29-year period at the Southwest National Primate Research Center. Results The anatomic locations affected in decreasing order were the stomach, small intestine, cecum, esophagus and colon. The most common clinical history was weight loss. The most frequent associated pathology included gastrointestinal inflammation and ulceration, emaciation, peritonitis, intussusception, pneumonia, and aspiration. Trichobezoars were the cause of death in nine Baboons and the reason for euthanasia in 12. Females were 2.14 times more likely than males to be affected. The greater the percentage of group housing time, the more likely the Baboon is to develop trichobezoars. Conclusions The Baboon may present a useful model to evaluate the etiology, genetic predisposition, physiopathology, neurobiology, and treatment response of trichobezoars.
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Spontaneous gallbladder pathology in Baboons
Journal of Medical Primatology, 2009Co-Authors: J.l. Slingluff, Edward J. Dick, Jeff T. Williams, Lance Blau, Adam Blau, Gene B. HubbardAbstract:Background Gallbladder pathology (GBP) is a relatively uncommon, naturally occurring morbidity in both Baboons and humans. Methods A retrospective analysis was performed on 7776 necropsy reports over a 20 year period to determine the prevalence of Baboon GBP. Results Ninety-seven cases of GBP were identified, yielding a 20 year population prevalence of 1.25%. GBP is more common in adult female Baboons, occurring with a female to male ratio of nearly 2:1. Among gallbladder pathologies, cholecystitis (35.1%) and cholelithiasis (29.9%) were the most prevalent abnormalities, followed by hyperplasia (16.5%), edema (15.5%), amyloidosis (5.2%), fibrosis (4.1%), necrosis (4.1%), and hemorrhage (1.0%). Conclusion Many epidemiologic similarities exist between GBP in Baboons and humans suggesting that the Baboon may serve as a reliable animal model system for investigating GBP in humans.
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feto placental adaptations to maternal obesity in the Baboon
Placenta, 2009Co-Authors: Darren Farley, Edward J. Dick, Anthony G Comuzzie, Maria Elizabeth Tejero, Paul B Higgins, Sherry L Werner, Susan L Jenkins, Cun Li, Jae Hyek Choi, Gene B. HubbardAbstract:Abstract Maternal obesity is present in 20–34% of pregnant women and has been associated with both intrauterine growth restriction and large-for-gestational age fetuses. While fetal and placental functions have been extensively studied in the Baboon, no data are available on the effect of maternal obesity on placental structure and function in this species. We hypothesize that maternal obesity in the Baboon is associated with a maternal inflammatory state and induces structural and functional changes in the placenta. The major findings of this study were: 1) decreased placental syncytiotrophoblast amplification factor, intact syncytiotrophoblast endoplasmic reticulum structure and decreased system A placental amino acid transport in obese animals; 2) fetal serum amino acid composition and mononuclear cells (PBMC) transcriptome were different in fetuses from obese compared with non-obese animals; and 3) maternal obesity in humans and Baboons is similar in regard to increased placental and adipose tissue macrophage infiltration, increased CD14 expression in maternal PBMC and maternal hyperleptinemia. In summary, these data demonstrate that in obese Baboons in the absence of increased fetal weight, placental and fetal phenotype are consistent with those described for large-for-gestational age human fetuses.
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Mortality in captive Baboons with seizures: A new model for SUDEP?
Epilepsia, 2009Co-Authors: C. Ákos Szabó, Gene B. Hubbard, M. Michelle Leland, Koyle D. Knape, Jake Feldman, Karin J.m. Mccoy, Jeff T. WilliamsAbstract:As the Baboon is a model of primary generalized epilepsy, we were interested in mortality of captive animals with a history of witnessed seizures. Causes of natural death were investigated in 46 seizure Baboons (SZ) and 78 nonepileptic controls (CTL), all of which underwent a complete pathological examination at the Southwest Foundation for Biomedical Research (SFBR) in San Antonio. SZ animals died at a younger age than the control Baboons (p
