The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Tanya M Smith - One of the best experts on this subject based on the ideXlab platform.
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age at first molar emergence in pan Troglodytes verus and variation in the timing of molar emergence among free living chimpanzees
Journal of Human Evolution, 2020Co-Authors: Jay Kelley, Gary T Schwartz, Tanya M SmithAbstract:Abstract Age at lower first molar (M1) emergence is a commonly used proxy for inferring life-history scheduling in fossil primates, but its utility is dependent on knowing to what extent extant populations vary in this datum and how this variation correlates with the scheduling of life-history variables. Here, we address the first of these issues among extant chimpanzees. While age at M1 emergence has been documented in several live individuals from the Kanyawara population of Pan Troglodytes schweinfurthii in Uganda, it has been estimated for only one individual of Pan Troglodytes verus, based on a deceased animal from the Tai Forest in Cote d’Ivoire. To further explore interpopulation variation in this variable in chimpanzees, and using dental histology, we calculated ages at death for two wild-shot individuals of P. t. verus with erupting M1, both collected in Liberia during the mid-1950s, and estimated ages at M1 emergence from the ages at death. The overall range for these two individuals is ∼4.2–4.6 yr, compared with an age of ∼3.7 yr for the individual from the Tai Forest, and
Jay Kelley - One of the best experts on this subject based on the ideXlab platform.
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age at first molar emergence in pan Troglodytes verus and variation in the timing of molar emergence among free living chimpanzees
Journal of Human Evolution, 2020Co-Authors: Jay Kelley, Gary T Schwartz, Tanya M SmithAbstract:Abstract Age at lower first molar (M1) emergence is a commonly used proxy for inferring life-history scheduling in fossil primates, but its utility is dependent on knowing to what extent extant populations vary in this datum and how this variation correlates with the scheduling of life-history variables. Here, we address the first of these issues among extant chimpanzees. While age at M1 emergence has been documented in several live individuals from the Kanyawara population of Pan Troglodytes schweinfurthii in Uganda, it has been estimated for only one individual of Pan Troglodytes verus, based on a deceased animal from the Tai Forest in Cote d’Ivoire. To further explore interpopulation variation in this variable in chimpanzees, and using dental histology, we calculated ages at death for two wild-shot individuals of P. t. verus with erupting M1, both collected in Liberia during the mid-1950s, and estimated ages at M1 emergence from the ages at death. The overall range for these two individuals is ∼4.2–4.6 yr, compared with an age of ∼3.7 yr for the individual from the Tai Forest, and
François Simon - One of the best experts on this subject based on the ideXlab platform.
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Identification of hepatitis B virus genome in faecal sample from wild living chimpanzee (Pan Troglodytes Troglodytes) in Gabon.
Journal of Clinical Virology, 2005Co-Authors: Maria Makuwa, Sandrine Souquière, Stephen L. Clifford, Augustin Mouinga-ondémé, Mireille Bawe-johnson, E. J. Wickings, S. Latour, François Simon, Pierre RoquesAbstract:Abstract Non-invasive faecal sampling in the equatorial forest in Gabon allowed the first identification of the hepatitis B virus (HBV-Ch RC170 ) genome in samples collected from wild chimpanzees ( Pan Troglodytes Troglodytes ). The HBV-Ch RCl70 sequence clustered with 100% bootstrap support with previous viral sequences obtained from Pan Troglodytes subspecies. This is the first evidence of HBV infection in wild apes and confirms that the HBV-like strains thus far characterized in captive apes are directly related to those circulating in the wild.
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env sequences of simian immunodeficiency viruses from chimpanzees in cameroon are strongly related to those of human immunodeficiency virus group n from the same geographic area
Journal of Virology, 2000Co-Authors: Sylvie Corbet, Michaela Mullertrutwin, Pierre Versmisse, Severine Delarue, Ahidjo Ayouba, John A Lewis, Soren Brunak, Paul M V Martin, Francoise Brunvezinet, François SimonAbstract:Human immunodeficiency virus type 1 (HIV-1) group N from Cameroon is phylogenetically close, in env, to the simian immunodeficiency virus (SIV) cpz-gab from Gabon and SIVcpz-US of unknown geographic origin. We screened 29 wild-born Cameroonian chimpanzees and found that three (Cam3, Cam4, and Cam5) were positive for HIV-1 by Western blotting. Mitochondrial DNA sequence analysis demonstrated that Cam3 and Cam5 belonged to Pan Troglodytes Troglodytes and that Cam4 belonged to P. t. vellerosus. Genetic analyses of the viruses together with serological data demonstrated that at least one of the two P. t. Troglodytes chimpanzees (Cam5) was infected in the wild, and revealed a horizontal transmission between Cam3 and Cam4. These data confirm that P. t. Troglodytes is a natural host for HIV-1-related viruses. Furthermore, they show that SIVcpz can be transmitted in captivity, from one chimpanzee subspecies to another. All three SIVcpz-cam viruses clustered with HIV-1 N in env. The full Cam3 SIVcpz genome sequence showed a very close phylogenetic relationship with SIVcpz-US, a virus identified in a P. t. Troglodytes chimpanzee captured nearly 40 years earlier. Like SIVcpz-US, SIVcpz-cam3 was closely related to HIV-1 N in env, but not in pol, supporting the hypothesis that HIV-1 N results from a recombination event. SIVcpz from chimpanzees born in the wild in Cameroon are thus strongly related in env to HIV-1 N from Cameroon, demonstrating the geographic coincidence of these human and simian viruses and providing a further strong argument in favor of the origin of HIV-1 being in chimpanzees.
Ahidjo Ayouba - One of the best experts on this subject based on the ideXlab platform.
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origin and biology of simian immunodeficiency virus in wild living western gorillas
Journal of Virology, 2009Co-Authors: Jun Takehisa, Ahidjo Ayouba, Elizabeth Bailes, Matthias H Kraus, Fran Van Heuverswyn, Julie M Decker, Yingying Li, Rebecca S Rudicell, Gerald Learn, Cecile NeelAbstract:Western lowland gorillas (Gorilla gorilla gorilla) are infected with a simian immunodeficiency virus (SIVgor) that is closely related to chimpanzee and human immunodeficiency viruses (SIVcpz and HIV-1, respectively) in west central Africa. Although existing data suggest a chimpanzee origin for SIVgor, a paucity of available sequences has precluded definitive conclusions. Here, we report the molecular characterization of one partial (BQ664) and three full-length (CP684, CP2135, and CP2139) SIVgor genomes amplified from fecal RNAs of wild-living gorillas at two field sites in Cameroon. Phylogenetic analyses showed that all SIVgor strains clustered together, forming a monophyletic lineage throughout their genomes. Interestingly, the closest relatives of SIVgor were not SIVcpzPtt strains from west central African chimpanzees (Pan Troglodytes Troglodytes) but human viruses belonging to HIV-1 group O. In trees derived from most genomic regions, SIVgor and HIV-1 group O formed a sister clade to the SIVcpzPtt lineage. However, in a tree derived from 5 pol sequences (900 bp), SIVgor and HIV-1 group O fell within the SIVcpzPtt radiation. The latter was due to two SIVcpzPtt strains that contained mosaic pol sequences, pointing to the existence of a divergent SIVcpzPtt lineage that gave rise to SIVgor and HIV-1 group O. Gorillas appear to have acquired this lineage at least 100 to 200 years ago. To examine the biological properties of SIVgor, we synthesized a full-length provirus from fecal consensus sequences. Transfection of the resulting clone (CP2139.287) into 293T cells yielded infectious virus that replicated efficiently in both human and chimpanzee CD4 T cells and used CCR5 as the coreceptor for viral entry. Together, these results provide strong evidence that P. t. Troglodytes apes were the source of SIVgor. These same apes may also have spawned the group O epidemic; however, the possibility that gorillas served as an intermediary host cannot be excluded.
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env sequences of simian immunodeficiency viruses from chimpanzees in cameroon are strongly related to those of human immunodeficiency virus group n from the same geographic area
Journal of Virology, 2000Co-Authors: Sylvie Corbet, Michaela Mullertrutwin, Pierre Versmisse, Severine Delarue, Ahidjo Ayouba, John A Lewis, Soren Brunak, Paul M V Martin, Francoise Brunvezinet, François SimonAbstract:Human immunodeficiency virus type 1 (HIV-1) group N from Cameroon is phylogenetically close, in env, to the simian immunodeficiency virus (SIV) cpz-gab from Gabon and SIVcpz-US of unknown geographic origin. We screened 29 wild-born Cameroonian chimpanzees and found that three (Cam3, Cam4, and Cam5) were positive for HIV-1 by Western blotting. Mitochondrial DNA sequence analysis demonstrated that Cam3 and Cam5 belonged to Pan Troglodytes Troglodytes and that Cam4 belonged to P. t. vellerosus. Genetic analyses of the viruses together with serological data demonstrated that at least one of the two P. t. Troglodytes chimpanzees (Cam5) was infected in the wild, and revealed a horizontal transmission between Cam3 and Cam4. These data confirm that P. t. Troglodytes is a natural host for HIV-1-related viruses. Furthermore, they show that SIVcpz can be transmitted in captivity, from one chimpanzee subspecies to another. All three SIVcpz-cam viruses clustered with HIV-1 N in env. The full Cam3 SIVcpz genome sequence showed a very close phylogenetic relationship with SIVcpz-US, a virus identified in a P. t. Troglodytes chimpanzee captured nearly 40 years earlier. Like SIVcpz-US, SIVcpz-cam3 was closely related to HIV-1 N in env, but not in pol, supporting the hypothesis that HIV-1 N results from a recombination event. SIVcpz from chimpanzees born in the wild in Cameroon are thus strongly related in env to HIV-1 N from Cameroon, demonstrating the geographic coincidence of these human and simian viruses and providing a further strong argument in favor of the origin of HIV-1 being in chimpanzees.
Cecile Neel - One of the best experts on this subject based on the ideXlab platform.
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origin and biology of simian immunodeficiency virus in wild living western gorillas
Journal of Virology, 2009Co-Authors: Jun Takehisa, Ahidjo Ayouba, Elizabeth Bailes, Matthias H Kraus, Fran Van Heuverswyn, Julie M Decker, Yingying Li, Rebecca S Rudicell, Gerald Learn, Cecile NeelAbstract:Western lowland gorillas (Gorilla gorilla gorilla) are infected with a simian immunodeficiency virus (SIVgor) that is closely related to chimpanzee and human immunodeficiency viruses (SIVcpz and HIV-1, respectively) in west central Africa. Although existing data suggest a chimpanzee origin for SIVgor, a paucity of available sequences has precluded definitive conclusions. Here, we report the molecular characterization of one partial (BQ664) and three full-length (CP684, CP2135, and CP2139) SIVgor genomes amplified from fecal RNAs of wild-living gorillas at two field sites in Cameroon. Phylogenetic analyses showed that all SIVgor strains clustered together, forming a monophyletic lineage throughout their genomes. Interestingly, the closest relatives of SIVgor were not SIVcpzPtt strains from west central African chimpanzees (Pan Troglodytes Troglodytes) but human viruses belonging to HIV-1 group O. In trees derived from most genomic regions, SIVgor and HIV-1 group O formed a sister clade to the SIVcpzPtt lineage. However, in a tree derived from 5 pol sequences (900 bp), SIVgor and HIV-1 group O fell within the SIVcpzPtt radiation. The latter was due to two SIVcpzPtt strains that contained mosaic pol sequences, pointing to the existence of a divergent SIVcpzPtt lineage that gave rise to SIVgor and HIV-1 group O. Gorillas appear to have acquired this lineage at least 100 to 200 years ago. To examine the biological properties of SIVgor, we synthesized a full-length provirus from fecal consensus sequences. Transfection of the resulting clone (CP2139.287) into 293T cells yielded infectious virus that replicated efficiently in both human and chimpanzee CD4 T cells and used CCR5 as the coreceptor for viral entry. Together, these results provide strong evidence that P. t. Troglodytes apes were the source of SIVgor. These same apes may also have spawned the group O epidemic; however, the possibility that gorillas served as an intermediary host cannot be excluded.
