| full-length complementary dna of hepatitis c virus genome from an infectious blood sample. | we constructed a full-length complementary dna (cdna) clone of hepatitis c virus (hcv) from a blood sample of an hcv carrier. the blood from the carrier was eventually transfused to a patient who later developed typical posttransfusion hepatitis c. it was also shown to be infectious to chimpanzees. we obtained 12 overlapping cdna fragments altogether, covering the entire hcv genome. by subcloning and sequencing, clones considered to constitute the major population were selected. we could also de ... | 1998 | 9462666 |
| evolutionary sequence comparisons using high-density oligonucleotide arrays. | we explored the utility of high-density oligonucleotide arrays (dna chips) for obtaining sequence information from homologous genes in closely related species. orthologues of the human brca1 exon 11, all approximately 3.4 kb in length and ranging from 98.2% to 83.5% nucleotide identity, were subjected to hybridization-based and conventional dideoxysequencing analysis. retrospective guidelines for identifying high-fidelity hybridization-based sequence calls were formulated based upon dideoxyseque ... | 1998 | 9462745 |
| comparative mapping of human alphoid satellite dna repeat sequences in the great apes. | heterochromatic regions of chromosomes contain highly repetitive, tandemly arranged dna sequences that undergo very rapid variation compared to unique dna sequences that are predominantly conserved. in this study the chromosomal basis of speciation has been looked at in terms of repeat sequences. we have hybridized twenty-one chromosome-specific human alphoid satellite dna probes to metaphase spreads of the chimpanzee (pan troglodytes), gorilla (gorilla gorilla), and orangutan (pongo pygmaeus) t ... | 1997 | 9465402 |
| evolution of immunologic functions of the mammary gland and the postnatal development of immunity. | physiologic delays in production of immune factors occur in mammals including homo sapiens. this finding is counter to a basic tenet of biologic evolution, because such delays increase the risk of infections. the disadvantage is, however, offset by defense factors in milk of the species in whom the developmental delay occurs. reciprocal relationships between the production of immune factors by the lactating mammary gland and the production of those defense agents during early infancy are found i ... | 1998 | 9475278 |
| departure from neutrality at the mitochondrial nadh dehydrogenase subunit 2 gene in humans, but not in chimpanzees. | to test whether patterns of mitochondrial dna (mtdna) variation are consistent with a neutral model of molecular evolution, nucleotide sequences were determined for the 1041 bp of the nadh dehydrogenase subunit 2 (nd2) gene in 20 geographically diverse humans and 20 common chimpanzees. contingency tests of neutrality were performed using four mutational categories for the nd2 molecule: synonymous and nonsynonymous mutations in the transmembrane regions, and synonymous and nonsynonymous mutations ... | 1998 | 9475751 |
| [anatomic and functional features of venous valves]. | the comparison of the venous system in the human organism, and in particular the venous valves of the lower limbs, with studies conducted in animal models helped us to understand better the mechanisms involved in adapting to the upright position and walking. we examined work conducted in several species from the horse to the dog, especially in animals who often take on an upright position such as the chimpanzee and the kangouroo, in search for structures comparable to those in man. different typ ... | 1997 | 9480339 |
| characterization of the bovine epsilon gene. | immunoglobulin e is quantitatively a minor immunoglobulin class in serum, but nevertheless the major class of antibody mediating type i hypersensitivity reactions and hence, type i allergic phenomena. the bovine epsilon gene is one of the as yet uncharacterized mammalian immunoglobulin genes. we have therefore cloned and determined the cdna sequence and genomic organization of the gene. it contains four constant region domain-encoding exons (ch1 to ch4) with a high homology to sheep c epsilon (8 ... | 1997 | 9486110 |
| immunity in chimpanzees chronically infected with hepatitis c virus: role of minor quasispecies in reinfection. | we have previously reported that chimpanzees chronically infected with hepatitis c virus (hcv) could be reinfected, even with the original infecting strain. in this study we tested the hypothesis that this might reflect the presence of minor quasispecies to which there was little or no immunity. to evaluate this hypothesis, we sequenced multiple clones taken at intervals after primary infection and rechallenge from four chronically infected chimpanzees. the inoculum used in these studies (hcv-h, ... | 1998 | 9499020 |
| human endogenous retrovirus k homologous sequences and their coding capacity in old world primates. | the coding capacity for retroviral gag and env proteins has been maintained in human endogenous retroviruses of the herv-k family. herv-k homologous sequences have been found in all old world primates. here, we examined old world primate species for the presence of full-length herv-k gag and env genes and the presence of gag and env open reading frames as determined by the protein truncation test. full-length herv-k env genes were found in dnas of all old world primate species, whereas open read ... | 1998 | 9499038 |
| recent origin of hla-drb1 alleles and implications for human evolution. | the hla class i and class ii loci are the most highly polymorphic coding regions in the human genome. based on the similarity of the coding sequences of alleles between species, it has been claimed that the hla polymorphism is ancient and predates the separation of human (homo) and chimpanzee (pan), 4-7.4 myr ago. analysis of intron sequences, however, provides support for a more recent origin and for rapid generation of alleles at the hla class ii drb1 locus. the human drb1 alleles can be divid ... | 1998 | 9500545 |
| evaluation of assays for antibody to hepatitis e virus by a serum panel. hepatitis e virus antibody serum panel evaluation group. | few data are available to evaluate the performance of existing assays for antibody to the hepatitis e virus (anti-hev). a panel of 164 randomized and coded sera was tested for anti-hev by 12 different assays. the panel included a dilution series of an early convalescent human serum, known-positive sera (undiluted human sera obtained 2 months to 13 years after acute hepatitis e, and postinoculation chimpanzee sera), known-negative sera (preinoculation chimpanzee sera; sera from chimpanzees with h ... | 1998 | 9500718 |
| the 5-ht transporter gene-linked polymorphic region (5-httlpr) in evolutionary perspective: alternative biallelic variation in rhesus monkeys. rapid communication. | by conferring allele-specific transcriptional activity on the 5-ht transporter gene promoter in humans, the 5-ht transporter gene-linked polymorphic region (5-httlpr) influences a constellation of personality traits related to anxiety and increases the risk for neurodevelopmental, neurodegenerative, and psychiatric disorders. here we have analyzed the presence and variability of the 5-httlpr in several species of primates including humans, and other mammals. pcr, southern blot, and sequence anal ... | 1997 | 9503271 |
| biological and immunological aspects of hepatitis c virus infection in chimpanzees. | | 1998 | 9507814 |
| allelic diversity at the primate mhc-dmb locus: presence of a conserved tyrosine inhibitory motif in the cytoplasmic tail. | ten new primate mhc-dmb complete cdna sequences have been obtained in chimpanzee (n=four), gorilla (n=three) and orangutan (n=three); this gene has not been previously studied in these species. exonic allelism has been recorded all along the molecule domains and also in the leader peptide, but not in the transmembrane segment. an analysis of the residues critical in the conformation of the mhc-dr peptide-binding site was done in order to look for a mhc-dr homologue site; synonymous substitutions ... | 1998 | 9510373 |
| molecular cloning and sequence analysis of interleukin 16 from nonhuman primates and from the mouse. | interleukin 16 (il-16) is synthesized as a 67 000 mr precursor (pro-il-16), but only a carboxy terminal part of 12 000-14 000 mr is secreted by cd8(+) lymphocytes. this lymphokine binds to cd4 and has been shown to induce migration, affect the activation state of t cells, and inhibit immunodeficiency virus replication. it has been suggested that cd8(+) cell-derived soluble factors play a pivotal role in protecting natural-host nonhuman primates from developing immunodeficiency following siv infe ... | 1998 | 9510557 |
| chimpanzee variation facilitates the interpretation of the incisive suture closure in south african plio-pleistocene hominids. | for a better understanding of early hominid growth patterns, we need to compare skeletal maturation among humans and chimpanzees. this study provides new data on variation of the incisive suture closure in extant species to facilitate the understanding of growth patterns among south african plio-pleistocene hominids. the complete anterior closure of the incisive suture occurs early during human life, mostly before birth. in contrast, in chimpanzees a complete anterior closure occurs mostly after ... | 1998 | 9511909 |
| multiphasic growth models and the evolution of prolonged growth exemplified by human brain evolution. | new models for multiphasic growth are presented. they are illustrated by analysis of brain growth in humans and chimpanzees, and the results are used to test the hypothesis of evolution by proportional growth prolongation: that all descendant growth phases are extended by the same factor while each remains at the ancestral growth rate. the results are consistent with the hypothesis and imply that gross brain weight increase towards humans required change in only one growth parameter: prolongatio ... | 1998 | 9514650 |
| use of leaves as cushions to sit on wet ground by wild chimpanzees. | a new type of tool use, leaf cushion, by wild chimpanzees (pan troglodytes verus) at bossou, guinea, was found. we report two cases: one is indirect evidence; the other is direct observation of a chimpanzee who used the tool. both cases indicate that chimpanzees used a set of leaves as a cushion while sitting on wet ground. chimpanzees at bossou show various kinds of tool use, some of which are unique to the community. most of these behavioral patterns are substance tool use for obtaining food, ... | 1998 | 9519241 |
| analysis of hepatitis c virus-inoculated chimpanzees reveals unexpected clinical profiles. | the clinical course of hepatitis c virus (hcv) infections in a chimpanzee cohort was examined to better characterize the outcome of this valuable animal model. results of a cross-sectional study revealed that a low percentage (39%) of hcv-inoculated chimpanzees were viremic based on reverse transcription (rt-pcr) analysis. a correlation was observed between viremia and the presence of anti-hcv antibodies. the pattern of antibodies was dissimilar among viremic chimpanzees and chimpanzees that cle ... | 1998 | 9525575 |
| extensive diversification of human immunodeficiency virus type 1 subtype b strains during dual infection of a chimpanzee that progressed to aids. | a chimpanzee (c-499) infected for more than 9 years with two subtype b isolates of human immunodeficiency virus type 1 (hiv-1), one (hiv-1(sf2)) that replicates poorly and one (hiv-1(lav-1b)) that replicates efficiently in chimpanzees, died of aids 11 years after initial infection (f. j. novembre et al., j. virol. 71:4086-4091, 1997). nucleotide sequence and phylogenetic analyses of the c2 to v5 region of env (c2-v5env) in proviral dna from peripheral blood lymphocytes obtained 22 months before ... | 1998 | 9525623 |
| experimental infection of chimpanzees with hepatitis g virus and genetic analysis of the virus. | hepatitis g virus (hgv) was transmitted to 2 chimpanzees by inoculation with human plasma containing approximately 10(8) genome equivalents (ge) of hgv. the infection was characterized by the late appearance (weeks 10 and 11 after inoculation [pi]) of viremia that persisted throughout the 120-week follow-up. serum hgv titer increased steadily until it plateaued at 10(6)-10(7) ge/ml. however, despite this relatively high titer, neither of the chimpanzees developed hepatitis. the sequence of the v ... | 1998 | 9534956 |
| free amino acids in milks of human subjects, other primates and non-primates. | preterm and term transitional milks of human subjects and mature milks of human subjects, non-human primates and non-primates were analysed for free amino acids (aa) using precolumn phenylisothiocyanate derivatization and liquid chromatography. differences in free aa between three types of human milk were small. milks of pinnipeds (seals and sea lions) contained the highest levels of total free aa (8634-20,862 mumol/l), while the milks of cows and sheep had the lowest levels of total free aa (10 ... | 1998 | 9536856 |
| technical note: chromosomal and mtdna analysis of oliver. | oliver is an african ape whose species identity has been debated in the popular media and by various scientists since the early 1970s. although decisive morphological data has never been adduced on oliver, many reports indicated that oliver was morphologically unusual for a chimpanzee, particularly in his habitual bipedal posture. in addition, his diploid chromosome number was reported to be inconsistent with either human or chimpanzee, but instead intermediate between those species. we performe ... | 1998 | 9545080 |
| estimation of the transition/transversion ratio. | a simple method for estimating the transition/transversion ratio was developed. this method can be applied to not only two sequences but also more than two sequences. the statistical properties of the method and some other methods were examined by numerical computation and computer simulation. the results obtained showed that, in terms of bias and variance, the new method gives a better estimate of the transition/transversion ratio than do the other examined methods. the new method was applied t ... | 1998 | 9545463 |
| transgenic mouse expressing a full-length hepatitis c virus cdna. | hepatitis c virus (hcv), a major causative agent of post transfusion non-a, non-b hepatitis (nanbh), can only infect humans and chimpanzees. we produced nine transgenic mouse lines carrying a full-length hcv cdna with the human serum amyloid p component (hsap) promoter that can direct liver-specific expression. in one of these lines hcv mrna and hcv core protein were detected in the liver of the transgenic mouse, although the levels of expression were very low. in addition, hcv-related antibody ... | 1998 | 9548442 |
| horizontal cell connections with short wavelength-sensitive cones in the retina: a comparison between new world and old world primates. | recent studies in the old world macaque monkey have shown that the two horizontal cell types h1 and h2 differ with respect to their connections to short wavelength-sensitive (sws) cones. we wanted to establish whether this pattern of connectivity is common to all primates. the connections of horizontal cells with sws cones were studied in the retinas of two species of new world (marmoset and tamarin) and two species of old world (orangutan and chimpanzee) primates by using a double-labelling tec ... | 1998 | 9548697 |
| contrasting levels of dna polymorphism at the autosomal and x-linked visual color pigment loci in humans and squirrel monkeys. | the x-linked color pigment (opsin) locus is known to be highly polymorphic in the squirrel monkey and other new world monkeys. to see whether this is also the case for the autosomal (blue) opsin locus, we obtained 32 squirrel monkey and 30 human blue opsin gene sequences. no amino acid polymorphism was found in either the squirrel monkey sample or the human sample, contrary to the situation at the x-linked opsin locus. this sharp contrast in the level of polymorphism might be due to differences ... | 1998 | 9549095 |
| a hominoid-specific nuclear insertion of the mitochondrial d-loop: implications for reconstructing ancestral mitochondrial sequences. | a nuclear integration of a mitochondrial control region sequence on human chromosome 9 has been isolated. pcr analyses with primers specific for the respective insertion-flanking nuclear regions showed that the insertion took place on the lineage leading to hominoidea (gibbon, orangutan, gorilla, chimpanzee, and human) after the old world monkey-hominoidea split. the sequences of the control region integrations were determined for humans, chimpanzees, gorillas, orangutans, and siamangs. these se ... | 1998 | 9549097 |
| chimpanzee dendritic cells derived in vitro from blood monocytes and pulsed with antigen elicit specific immune responses in vivo. | dendritic cells differentiated in vitro from blood and other sources using cytokines hold particular promise as immunotherapeutic agents in cancer. however, there are currently no data to show that human in vitro-derived dendritic cells are immunogenic in vivo. we have developed a primate model of immunotherapy using dendritic cells differentiated in vitro from blood monocytes by culturing with human granulocyte/ macrophage colony-stimulating factor and interleukin-4. we measured the immune resp ... | 1998 | 9551366 |
| review on the physical growth in primates. | j.m. tanner concluded in 1962 that the growth velocity curve in body weight shows two peaks in primates but only one peak in the other mammals, and that the first peak in primates corresponds phylogenetically to the peak in the other mammals. many reports on the physical growth of primates have been accumulated in the past 70 years. using some of them as a basis, the author illustrated the normative velocity curves (increment curves) of the weight of monkeys, chimpanzees and humans, and reconsid ... | 1998 | 9554466 |
| functional role of hepatitis c virus chimeric glycoproteins in the infectivity of pseudotyped virus. | the putative envelope glycoproteins of hepatitis c virus (hcv) likely play an important role in the initiation of viral infection. available information suggests that the genomic regions encoding the putative envelope glycoproteins, when expressed as recombinant proteins in mammalian cells, largely accumulate in the endoplasmic reticulum. in this study, genomic regions which include the putative ectodomain of the e1 (amino acids 174 to 359) and e2 (amino acids 371 to 742) glycoproteins were appe ... | 1998 | 9557633 |
| recombinant respiratory syncytial virus (rsv) bearing a set of mutations from cold-passaged rsv is attenuated in chimpanzees. | a set of five missense mutations previously identified by nucleotide sequence analysis of subgroup a cold-passaged (cp) respiratory syncytial virus (rsv) has been introduced into a recombinant wild-type strain of rsv. this recombinant virus, designated ra2cp, appears to replicate less efficiently in the upper and lower respiratory tracts of seronegative chimpanzees than either biologically derived or recombinant wild-type rsv. infection with ra2cp also resulted in significantly less rhinorrhea a ... | 1998 | 9557743 |
| the hypoglossal canal and the origin of human vocal behavior. | the mammalian hypoglossal canal transmits the nerve that supplies the muscles of the tongue. this canal is absolutely and relatively larger in modern humans than it is in the african apes (pan and gorilla). we hypothesize that the human tongue is supplied more richly with motor nerves than are those of living apes and propose that canal size in fossil hominids may provide an indication about the motor coordination of the tongue and reflect the evolution of speech and language. canals of gracile ... | 1998 | 9560291 |
| evaluation of b and t-cell responses in chimpanzees immunized with hepagene, a hepatitis b vaccine containing pre-s1, pre-s2 gene products. | approximately 5-10% of healthy young adults receiving the commercially available hepatitis b vaccine (either serum derived or recombinant) fail to mount an adequate immune response. this nonresponder rate has prompted the demand for more immunogenic vaccines. an alternative to the currently licensed hepatitis b vaccines is hepagene, a novel recombinant hepatitis b vaccine containing s, pre-s1 and pre-s2 antigenic components, produced in the mouse c127i clonal cell line after transfection of the ... | 1998 | 9569463 |
| comparison of human, primate, and canine femora: implications for biomaterials testing in total hip replacement. | the canine model remains an animal of choice for determining the efficacy and safety of various materials and designs used in human total hip replacement (thr). the primate also is used in orthopedic-related research for studying limb anatomy, gait, and age-related bone loss. in order to better understand the appropriateness of these animal models for human thr, external morphologies of thirty-three adult caucasian human, sixteen adult chimpanzee, and forty-two adult greyhound femora were compar ... | 1998 | 9570081 |
| hiv-1 vaccine candidate evaluation in non-human primates. | the development of an hiv-1 vaccine in the last 13 years from an industrial point of view has focused on evaluating potential vaccine candidates in non-human primates. this review discusses the hiv-1 vaccine candidates that have been tested in chimpanzees or monkeys and includes those based on recombinant gp120, recombinant gp160, different viral and bacterial vectors expressing gp120, gp160, or only v3 peptide, naked dna vaccines, and whole inactivated viruses. to help understand the result of ... | 1997 | 9570296 |
| identification of conserved potentially regulatory sequences of the sry gene from 10 different species of mammals. | we have sequenced the 5' region of the sry gene from human, chimpanzee, sheep, and mouse and from four additional mammalian species, not previously characterized (gorilla, gazelle, rat, and guinea pig). in order to identify conserved dna elements potentially involved in the regulation of the sry gene, the newly determined sequences were analyzed and compared to all mammalian sry promoter sequences available at present. ten highly conserved potential regulatory elements have been identified in al ... | 1998 | 9571157 |
| loss of cd4+ t cells in human immunodeficiency virus type 1-infected chimpanzees is associated with increased lymphocyte apoptosis. | supportive evidence that apoptosis contributes to loss of cd4+ lymphocytes in human immunodeficiency virus type 1 (hiv-1)-infected humans comes from an apparent lack of abnormal apoptosis in apathogenic lentivirus infections of nonhuman primates, including hiv-1 infection of chimpanzees. two female chimpanzees were inoculated, one cervically and the other intravenously, with hiv-1 derived from the lai/lav-1b strain, which was isolated from a chimpanzee infected with the virus for 8 years. within ... | 1998 | 9573225 |
| isolation of a hepadnavirus from the woolly monkey, a new world primate. | hepatitis b virus (hbv) infections are a major worldwide health problem with chronic infections leading to cirrhosis and liver cancer. viruses related to human hbv have been isolated from birds and rodents, but despite efforts to find hepadnaviruses that infect species intermediate in evolution between rodents and humans, none have been described. we recently isolated a hepadnavirus from a woolly monkey (lagothrix lagotricha) that was suffering from fulminant hepatitis. phylogenetic analysis of ... | 1998 | 9576957 |
| transcripts of a chimeric cdna clone of hepatitis c virus genotype 1b are infectious in vivo. | we constructed a chimeric cdna clone of hepatitis c virus (hcv) that is infectious. the chimeric genome encodes the polyprotein of a genotype 1b strain (hc-j4) of hcv and replicates via 5' and 3' untranslated regions of a genotype 1a strain. the infectivity of three full-length cdna clones was tested by direct injection of rna transcripts into the liver of a chimpanzee. the chimpanzee became infected with hcv and the viral titer increased over time from 10(2) genome equivalents (ge)/ml at week 1 ... | 1998 | 9581788 |
| coamplification and dispersion of adjacent human endogenous retroviral herv-h and herv-e elements; presence of spliced hybrid transcripts in normal leukocytes. | in an rt-pcr study of herv-h spliced subgenomic transcripts, we found transcripts with herv-h leader and protease-encoding sequences spliced to herv-e integrase-encoding sequences in lymphocytes from healthy blood donors. in other cell types, including two t-cell leukemia cell lines, these transcripts were absent. the pcr fragments of the hybrid transcripts contained two open reading frames (orfs). one was a hybrid herv-h protease/herv-e integrase orf and the other was the herv-e envelope surfac ... | 1998 | 9581793 |
| comparative study of the genomic organization of dna repeats within the 5'-flanking region of the natural resistance-associated macrophage protein gene (nramp1) between humans and great apes. | the human nramp1 gene located on chromosome (chr) region 2q35 is a candidate gene for increased risk of infection by several intracellular macrophage parasites, including m. tuberculosis and m. leprae. in search for a possible mutational hot spot, we have analyzed a 3.5-kb region 5' to nramp1 that is highly enriched for dna repeat sequences. the repeat sequences could be grouped into one mer element and six alu elements, representing five alu subfamilies, that had integrated in the same dna regi ... | 1998 | 9585430 |
| orangutan alpha-satellite monomers are closely related to the human consensus sequence. | alpha-satellite is a family of tandemly repeated dna found at the centromeric regions of all human and primate chromosomes. human alpha-satellite subsets are largely chromosome-specific and have been further grouped into four suprachromosomal families (sfs), each characterized by a unique set of monomeric types. although chimpanzee and gorilla alpha-satellites share sufficient sequence similarity to fit the established sfs, the assumption that the derived human alpha-satellite consensus and mono ... | 1998 | 9585431 |
| molecular cloning of the cdna encoding the carboxy-terminal domain of chimpanzee apolipoprotein(a): an asp57 --> asn mutation in kringle iv-10 is associated with poor fibrin binding. | insight into the structural features of human lipoprotein(a) [lp(a)] which underlie its functional implication in fibrinolysis may be gained from comparative studies of apo(a). indeed, cloning of rhesus monkey apo(a) has shown that a trp72 --> arg mutation in the lysine-binding site (lbs) of kiv-10 leads to loss of lysine-binding properties of the rhesus lp(a) particle. consequently, comparative studies of apo(a) sequences in different old world monkey species should further our understanding of ... | 1998 | 9585533 |
| estimation of african ape body length from femur length. | the estimation from long bone lengths of stature in humans or body size in apes has a deep history in physical anthropology. to date, we can enumerate at least five different statistical methods for making such estimations. these methods are: (1) the regression of body length on long bone length (inverse calibration), (2) regression of long bone length on body length followed by solving for body length (classical calibration), (3) major axis regression of body length on long bone length, (4) red ... | 1998 | 9595359 |
| a survey for 32 nucleotide deletion in the ccr-5 chemokine receptor gene (deltaccr-5) conferring resistance to human immunodeficiency virus type 1 in different ethnic groups and in chimpanzees. | the 32 nucleotide deletion in the ccr-5 chemokine receptor gene referred to as deltaccr-5 has been shown to confer resistance to hiv-1. using pcr, 1,105 human subjects and 33 common chimpanzees were genotyped attributing them to one of the three possible genotypes: wild-type homozygote (w/w); deltaccr-5 homozygote (deltaccr-5/deltaccr-5) and deltaccr-5/wild-type heterozygotes (deltaccr-5/w). the ethnic groups investigated included different middle eastern nationalities (mainly arab) and russians ... | 1998 | 9598936 |
| transmission of hepatitis c virus infection to tree shrews. | although hepatitis c virus (hcv) infection can be reproduced in chimpanzees, these animals are rare and expensive. tree shrews (tupaias) are small animals, closely related to primates, which adapt easily to a laboratory environment. in this work we have investigated the susceptibility of tupaia belangeri chinensis to hcv infection. tupaias caught in the wild in yunnan (china) were inoculated in china with hcv genotype 1b (study a) and in spain with a mixture of genotypes 1b, 1a, and 3 (study b). ... | 1998 | 9601519 |
| transcription and weak expression of hla-drb6: a gene with anomalies in exon 1 and other regions. | hla-drb6 is one of the human major histocompatibility complex (mhc) genes present in dr1, dr2, and dr10 haplotypes (approximately 26% of individuals). it shows several anomalies in human and non-human primates, including exon 2 stop codons (non-randomly grouped between codons 74 and 94) and a promoter region, and an exon 1 coming from an inserted retrovirus. it has been shown that not only chimpanzee but also human mhc-drb6 lack the usual 3' untranslated (ut) polyadenylation signal, and in the p ... | 1998 | 9601939 |
| human xenomitochondrial cybrids. cellular models of mitochondrial complex i deficiency. | the subunits forming the mitochondrial oxidative phosphorylation system are coded by both nuclear and mitochondrial genes. recently, we attempted to introduce mtdna from non-human apes into a human cell line lacking mtdna (rho degrees), and succeeded in producing human-common chimpanzee, human-pigmy chimpanzee, and human-gorilla xenomitochondrial cybrids (hxc). here, we present a comprehensive characterization of oxidative phosphorylation function in these cells. mitochondrial complexes ii, iii, ... | 1998 | 9603924 |
| chimpanzee lipoprotein(a): relationship between apolipoprotein(a) isoform size and the density profile of lipoprotein(a) in animals with different heterozygous apo(a) phenotypes. | in a previous study [c. doucet et al., j. lipid res 35:263-270, 1994], we have shown that plasma lipoprotein (a) [lp(a)] levels were significantly elevated in a population of unrelated chimpanzees as compared to those in normolipidemic human subjects. nonetheless, the inverse correlation between lp(a) levels and apolipoprotein (a) [apo(a)] isoforms typical of man was maintained in the chimpanzee. in the present study, we describe the density profiles of apo b- and apo a1-containing lipoproteins ... | 1998 | 9606039 |
| characterization of a novel class of interspersed ltr elements in primate genomes: structure, genomic distribution, and evolution. | retrovirus-like sequences and their solitary (solo) long terminal repeats (ltrs) are common repetitive elements in eukaryotic genomes. we reported previously that the tandemly arrayed genes encoding u2 snrna (the rnu2 locus) in humans and apes contain a solo ltr (u2-ltr) which was presumably generated by homologous recombination between the two ltrs of an ancestral provirus that is retained in the orthologous baboon rnu2 locus. we have now sequenced the orthologous u2-ltrs in human, chimpanzee, ... | 1998 | 9608047 |
| treatment of thrombocytopenia in chimpanzees infected with human immunodeficiency virus by pegylated recombinant human megakaryocyte growth and development factor. | three chimpanzees experimentally infected with human immunodeficiency virus (hiv) developed significant chronic thrombocytopenia after 5, 4, and 2 years, with peripheral platelet counts averaging 64 +/- 19 x 10(3)/microl (p = .004 compared with 228 +/- 92 x 10(3)/microl in 44 normal control animals), mean platelet volumes of 11.2 +/- 1.8 fl (p > .5 compared with 10.9 +/- 0. 7 fl in normal controls), endogenous thrombopoietin (tpo) levels of 926 +/- 364 pg/ml (p < .001 compared with 324 +/- 256 p ... | 1998 | 9616135 |
| hepatitis d viremia following orthotopic liver transplantation involves a typical hdv virion with a hepatitis b surface antigen envelope. | patients receiving orthotopic liver transplantation (olt) because of type d hepatitis frequently exhibit what appears to be an autonomous, or "isolated," hepatitis d virus (hdv) infection following the transplantation, with no evidence of hepatitis b virus (hbv) in the graft or in the serum. these observations have led to the hypothesis that hbv might not always be required for hdv infection, or that hdv could exist as a latent infection until rescued by hbv. alternatively, an apparently autonom ... | 1998 | 9620349 |
| structure and phylogenetic analysis of an endogenous retrovirus inserted into the human growth factor gene pleiotrophin. | a human endogenous retrovirus-like element (herv), flanked by long terminal repeats of 502 and 495 nucleotides is inserted into the human pleiotrophin (ptn) gene upstream of the open reading frame. based on its glu-trna primer binding site specificity and the location within the ptn gene, we named this element herv-e.ptn. herv-e.ptn appears to be a recombined viral element based on its high homology (70 to 86%) in distinct areas to members of two distantly related herv type c families, herv-e an ... | 1998 | 9621070 |
| peri-portal fibrosis of the liver due to natural or experimental infection with schistosoma mansoni occurs in the kenyan baboon. | the chronic granulomatous inflammation that occurs during schistosomiasis mansoni and its reparative healing lead to hepatic fibrosis, with subsequent portal hypertension (a life-threatening sequela). in the murine model, granuloma modulation invariably leads to formation of fibrous tissue and disposition of extracellular matrix. typically, < 10% of patients infected with schistosoma mansoni progress to clay-pipe-stem fibrosis. similar fibrosis occurs in chimpanzees during experimental infection ... | 1998 | 9625915 |
| infection of a chimpanzee with hepatitis c virus grown in cell culture. | culture supernatant harvested from daudi cells, a lymphoplastoid cell line, after 58 days of infection with the h77 strain of hepatitis c virus (hcv), was inoculated into a chimpanzee. hcv rna, as detected by rt-pcr, first appeared in the serum and liver 5 and 6 weeks, respectively, after inoculation. peripheral blood mononuclear cells (pbmc) collected on week 7 were also positive for hcv rna. the major sequences of hypervariable region 1 (hvr1) of the viral genome recovered from the inoculated ... | 1998 | 9634078 |
| limbic frontal cortex in hominoids: a comparative study of area 13. | the limbic frontal cortex forms part of the neural substrate responsible for emotional reactions to social stimuli. area 13 is one of the cortical areas long known to be part of the posterior orbitofrontal cortex in several monkey species, such as the macaque. its presence nevertheless in the human brain has been unclear, and the cortex of the frontal lobe of the great and lesser apes remains largely unknown. in this study area 13 was identified in human, chimpanzee, bonobo, gorilla, orangutan, ... | 1998 | 9637180 |
| use of experimenter-given cues during object-choice tasks by chimpanzees (pan troglodytes), an orangutan (pongo pygmaeus), and human infants (homo sapiens). | in a series of experiments, chimpanzees (pan troglodytes), an orangutan (pongo pygmaeus), and human infants (homo sapiens) were investigated as to whether they used experimenter-given cues when responding to object-choice tasks. five conditions were used in different phases: the experimenter tapping on the correct object, gazing plus pointing, gazing closely, gazing alone, and glancing without head orientation. the 3 subject species were able to use all of the experimenter-given cues, in contras ... | 1998 | 9642782 |
| distinguishing intentional from accidental actions in orangutans (pongo pygmaeus), chimpanzees (pan troglodytes), and human children (homo sapiens). | this study investigates the understanding of others' intentions in 2- and 3-year-old children, chimpanzees (pan troglodytes), and orangutans (pongo pygmaeus). during training, subjects learned to use a discriminative cue to select a baited box. during testing, the experimenter placed a marker on top of the baited box to inform the subject of the reward's location. however, the experimenter also accidentally dropped the marker on top of an unbaited box, so that during any given trial the experime ... | 1998 | 9642787 |
| [adult giant cell hepatitis with fatal outcome. clinicopathologic case report and reflections on pathogenesis]. | the occurrence of plasmodial giant cells in the liver is probably a morphological reaction pattern with the most diverse causes. in babies and infants, these changes occur in particular in neonatal hepatitis and intrahepatic and extrahepatic bile duct atresia. viral infections and/or autoimmune reactions are discussed etiologically in giant cell hepatitis in adults (adult gaint cell hepatitis, agch), which is much rarer. in some of the cases, there were conspicuously high titers against paramyxo ... | 1998 | 9648148 |
| primary sivsm isolates use the ccr5 coreceptor from sooty mangabeys naturally infected in west africa: a comparison of coreceptor usage of primary sivsm, hiv-2, and sivmac. | genetically divergent strains of simian immunodeficiency virus (siv) from macaques (mac), chimpanzees, and sooty mangabeys (sm) efficiently used rhesus and human ccr5 (r5), but not cxcr4 (xr4), for cell entry. thus far, however, no studies have characterized primary sivsm strains for their use of coreceptors derived from their own natural host. coreceptor usage of two primary, blood-derived sivsm isolates, sivsmsl92b and sivsmfns from naturally infected sooty mangabeys, was determined. primary s ... | 1998 | 9656999 |
| development of a human gamma interferon enzyme immunoassay and comparison with tuberculin skin testing for detection of mycobacterium tuberculosis infection. | a sensitive two-step simultaneous enzyme immunoassay (eia) for human gamma interferon (ifn-gamma) has been developed and used as an in vitro test for human tuberculosis (tb) in comparison with tuberculin skin testing. the eia was shown to be highly sensitive, detecting less than 0.5 iu of recombinant human ifn-gamma per ml within a linear detection range of 0.5 to 150 iu/ml. the assay was highly reproducible and specific for native ifn-gamma. in addition, the assay detected chimpanzee, orangutan ... | 1998 | 9665962 |
| toward a phylogenetic classification of primates based on dna evidence complemented by fossil evidence. | a highly resolved primate cladogram based on dna evidence is congruent with extant and fossil osteological evidence. a provisional primate classification based on this cladogram and the time scale provided by fossils and the model of local molecular clocks has all named taxa represent clades and assigns the same taxonomic rank to those clades of roughly equivalent age. order primates divides into strepsirhini and haplorhini. strepsirhines divide into lemuriformes and loriformes, whereas haplorhi ... | 1998 | 9668008 |
| molecular definition of pericentric inversion breakpoints occurring during the evolution of humans and chimpanzees. | high-resolution g-banding analysis has demonstrated remarkable morphological conservation of the chromosomes of the hominidae family members (humans, chimpanzees, gorillas, and orangutans), with the most notable differences between the genomes appearing as changes in heterochromatin distribution and pericentric inversions. pericentric inversions may have been important for the establishment of reproductive isolation and speciation of the hominoids as they diverged from a common ancestor. here th ... | 1998 | 9676431 |
| the mechanical effectiveness of erect and "bent-hip, bent-knee" bipedal walking in australopithecus afarensis. | it is universally accepted that the postcranial skeleton of the early hominid australopithecus afarensis shows adaptations, or at least exaptations, towards bipedalism. however, there continues to be a debate concerning the likely form of terrestrial bipedality: whether gait was erect, like our own, or "bent-hip, bent-knee" like the bipedalism of living chimpanzees. in this study we use predictive dynamic modelling to assess the mechanical effectiveness of al-288-1 under both hypotheses, on the ... | 1998 | 9680467 |
| sequence comparisons of non-human primate hiv-1 coreceptor homologues. | infection of non-human primate peripheral blood mononuclear cells (pbmcs) in vitro with primary human immunodeficiency virus type 1 (hiv-1) isolates is extremely inefficient and often unattainable. the mechanism of resistance to infection by primary hiv-1 isolates in chimpanzee and baboon pbmcs is unknown. in this study, two hiv-1 coreceptors, ccr5 and cxcr4, were sequenced from chimpanzee and baboon pbmcs to determine if any sequence variations or mutations in these genes could be responsible f ... | 1998 | 9683255 |
| platelets in thrombotic disorders: quantitative and qualitative platelet disorders predisposing to arterial thrombosis. | endogenous thrombopoietin (tpo) stimulates platelet production in nonhuman primates by inducing dose-dependent megakaryocyte development from early marrow hematopoietic progenitors and subsequent proliferation and endoreduplication. in nonhuman primates, recombinant human tpo, nonpegylated or pegylated rhu megakaryocyte growth and development factor produce log-linear responses in peak peripheral platelet counts (or peripheral platelet mass turnover) and marrow megakaryocyte volume, ploidy, numb ... | 1998 | 9685170 |
| human and nonhuman primate lymphocytes engrafted into scid mice reside in unique mesenteric lymphoid structures. | the present study compares the location and phenotype of b lineage lymphocytes in tissues from scid mice engrafted with pbmc of human, chimpanzee, and pig-tailed macaque origin. in mice repopulated with both human and nonhuman primate lymphocytes, plasma cells were found in the peritoneal cavity in vascularized structures located in the mesentery near the pancreas, intestines, and spleen. the predominant isotype of the plasma cells was igg; igm and iga cells were also present. kappa and lambda l ... | 1998 | 9686592 |
| origin of human chromosome 21 and its consequences: a 50-million-year-old story. | great apes (pongidae) possess a chromosome similar to human chromosome 21 (hsa21), whose trisomy was described in both chimpanzee and orangutan. having studied more than 200 mammalian species by chromosome banding techniques and reconstructed primates phylogeny, we reinvestigated, using fluorescence in situ hybridization, primate and non-primate mammals that we considered to possess a karyotype representative of their taxonomic group. dna sequences from hsa21 and human chromosome 3 (hsa3) are sy ... | 1998 | 9688515 |
| hepatitis c virus-specific ctl responses in pbmc from chimpanzees with chronic hepatitis c: determination of ctl and ctl precursor frequencies using a recombinant canarypox virus (alvac). | the aim of this study was to evaluate hcv-cytotoxic t lymphocyte response from pbmc in bulk ctl assays and in ctl precursor analyses using in vitro stimulation with canarypox virus (alvac) expressing hcv-capsid/e1/e2/ns2/ns3 antigens. canarypox virus is naturally host-range restricted and does not replicate or cause cytopathology on mammalian cells. pbmc were obtained from four chimpanzees with chronic hepatitis c infection and one uninfected chimpanzee. ctl from bulk culture of pbmc and ctl pre ... | 1998 | 9692864 |
| detection of widespread hepatocyte infection in chronic hepatitis c. | the controversial question of the extent of hepatocyte infection in chronic hepatitis c was re-examined in both chimpanzees and humans using a newly modified in situ hybridization (ish) method for detecting hepatitis c virus (hcv) rna. the specificity of the methodology for distinguishing positive- and negative-strand synthetic hcv rna was at least six magnitudes greater than the reverse-transcription polymerase chain reaction (rt-pcr) assay for hcv. the sensitivity of the methodology as determi ... | 1998 | 9696027 |
| dietary responses to fruit scarcity of wild chimpanzees at bossou, guinea: possible implications for ecological importance of tool use. | a 13-month ecological study was conducted at bossou, guinea, west africa, to elucidate how a community of wild chimpanzees (pan troglodytes verus) deals with the scarcity of main foods. during the study period, fruit availability fluctuated radically. the chimpanzees were confirmed to depend heavily on three "keystone resources" which were available when their main foods (fruit pulp) were scarce. these were fruits of musanga cecropioides, oil-palm (elaeis guineensis) nuts, and oil-palm pith. the ... | 1998 | 9696145 |
| shape of the piriform aperture in gorilla gorilla, pan troglodytes, and modern homo sapiens: characterization and polymorphism analysis. | by using new methodologies based on automatic image analysis, the shape of the piriform aperture was analyzed in gorilla gorilla (33 males, 13 females), pan troglodytes (35 males, 22 females), and modern homo sapiens (30 males, 12 females). the determination of the piriform aperture index (breadth/height) allowed the authors to demonstrate a marked elongation of the aperture in homo compared with gorilla and pan. individual characterization of the shape was possible with great precision and with ... | 1998 | 9696146 |
| object-use in free-ranging white-faced capuchins (cebus capucinus) in costa rica. | chimpanzees and capuchins demonstrate greater varieties and higher rates of tool-use when compared to other non-human primates. although capuchins have been studied extensively in captivity, data on their tool-using behavior under free-ranging conditions are limited. this is the first long-term field research to systematically study complex object manipulation in capuchins. the aims of this research are 1) to examine the types, rates, and contexts of tool- and object-use in free-ranging capuchin ... | 1998 | 9696147 |
| utilization of chimeras between human (hm-175) and simian (agm-27) strains of hepatitis a virus to study the molecular basis of virulence. | chimeras between human (hm-175) and simian (agm-27) strains of hepatitis a virus (hav) were constructed to evaluate the effect of the 2c gene of agm-27 on hav replication in cell culture and virulence in tamarins (saguinus mystax) and chimpanzees (pan troglodytes). kinetic studies and radioimmunofocus assays demonstrated that replacement of the 2c gene of hav/7, a cell culture-adapted strain of hm-175, with that of agm-27 drastically reduced the ability of the virus to replicate in cultured cell ... | 1998 | 9696843 |
| ascertainment bias cannot entirely account for human microsatellites being longer than their chimpanzee homologues. | a large majority of human microsatellite markers are longer than their homologues in chimpanzees, suggesting that more expansion mutations have occurred in the lineage leading to humans. however, such a length difference has also been explained as arising from the selection of unusually long microsatellites as genetic markers. in order to resolve this controversy and to establish the true source of the observed length differences, we have now conducted the necessary reciprocal study. we have com ... | 1998 | 9700197 |
| isolation of a gb virus-related genome from a chimpanzee. | recently, two new flaviviruses, gb virus a (gbv-a) and gb virus b (gbv-b), were identified in the plasma of a tamarin infected with the hepatitis gb agent. a third virus, gb virus c (gbv-c), was subsequently identified in humans. in the current study, representational difference analysis (rda) was used to search for a new virus in the serum of a chimpanzee that developed acute resolving hepatitis following inoculation with a pool of chimpanzee plasma. the plasma pool originated from serial passa ... | 1998 | 9700632 |
| detection in chimpanzees of a novel flavivirus related to gb virus-c/hepatitis g virus. | infection with hepatitis g virus (hgv) or gb virus-c (gbv-c) is widely distributed in human populations. viruses related to gbv-c/hgv have been recovered from several new world primate species, including tamarins, owl monkeys and marmosets. to understand more about the relationship between gb viruses and their hosts, we used primers from the 5' non-coding (5'nc), non-structural 3 (ns3) and ns5 regions in nested polymerase chain reactions to screen for related viruses infecting non-captive chimpa ... | 1998 | 9714234 |
| sequence and diversity of t-cell receptor alpha v, j, and c genes of the owl monkey aotus nancymaae. | we cloned and sequenced tcr alpha chain cdna of three healthy aotus nancymaae monkeys. fifteen different traj segments and 9 different trav genes were identified in the 29 rearrangements analyzed. as expected from the greater phylogenetic distance, a. nancymaae tra gene sequences diverged more from the human sequences than those of the chimpanzee or the rhesus macaque. however, no aotus traj segment or trav gene was found which lacked a human counterpart. these counterparts were aj02, aj05, aj09 ... | 1998 | 9716644 |
| fine specificity of anti-v3 antibodies induced in chimpanzees by hiv candidate vaccines. | the fine specificity of the anti-v3 antibody responses induced in chimpanzees immunized by various human immunodeficiency type 1 (hiv-1) candidate vaccines and challenged by heterologous strains of hiv-1 was analyzed by enzyme-linked immunosorbent assay (elisa) and pepscan epitope mapping. two chimpanzees immunized with the recombinant canarypox virus alvac-hiv (vcp125) expressing gp160mn and boosted with purified gp160mn/lai alone, then with both immunogens in combination, were not protected ag ... | 1998 | 9718117 |
| comparative mapping of the cri du chat and digeorge syndrome regions in the great apes. | structural variations between great ape and human chromosomes due to pericentric inversions and translocations have created at apparent controversy during the reconstruction of hominoid phylogeny. one such variation involves human chromosome 5, which is equivalent to chromosome 4 in chimpanzee and orangutan but equivalent to segments of chromosomes 4 and 19 in gorilla. obviously, neither banding patterns nor centromeric indecies in these chromosomes match. the pathological condition of cri du ch ... | 1998 | 9718678 |
| effect of iga1 protease on the ability of secretory iga1 antibodies to inhibit the adherence of streptococcus mutans. | secretory iga (siga) is the principal immunoglobulin isotype present in the mucosal secretions of humans. siga is thought to play a major role in host defense at these surfaces by inhibiting the colonization of potentially pathogenic microorganisms. a number of bacteria that are mucosal pathogens of humans produce a protease that specifically cleaves the iga1 subclass of humans and great apes at the hinge region to produce fab and fc fragments. in order to study the effect of iga1 protease on th ... | 1998 | 9719103 |
| a highly conserved microsatellite in the dystrophin gene of diverse mammalian species. | the presence of a ca repeat within the 3'-untranslated region (utr) of the dystrophin gene has been reported previously in several species. because microsatellites showing high cross-species homology can be conveniently used as markers in those species for which detailed linkage maps have not yet been developed, we evaluated whether the ca repeat could be amplified from a wide variety of mammalian species. using a single pair of canine-specific oligonucleotide primers, we successfully amplified ... | 1998 | 9720183 |
| evolutionary divergence of the oncogenes gli, hst and int2. | almost a quarter of a century ago, the banding patterns of human and other higher primate chromosomes were compared, creating a barrage of speculation. consequently, a number of approaches have been used to understand human descent. chromosome modifications are believed to be important in the origin of species, and pericentric inversions account for the majority of evolutionary chromosomal alterations seen in hominoidea. a comparative mapping fluorescence in situ hybridization technique, using l ... | 1998 | 9720300 |
| genetic immunization of chimpanzees chronically infected with the hepatitis b virus, using a recombinant retroviral vector encoding the hepatitis b virus core antigen. | cytotoxic t lymphocyte (ctl) activity and cd4+ helper t cell responses to the hepatitis b virus (hbv) core antigen (hbcag) have been implicated in clearance of acute and chronic hbv infections. we showed that intramuscular injections of a novel recombinant retroviral vector expressing an hbcag-neomycin phosphotransferase ii (hbc-neo) fusion protein induces hbc/eag-specific antibodies and cd4+ and cd8+ t cell responses in mice and rhesus monkeys. we have now immunized three chronically infected c ... | 1998 | 9721082 |
| recent human-specific spreading of a subtelomeric domain. | the recent spreading of a subtelomeric region at nine different human chromosome ends was characterized by a combination of segregation analyses, physical mapping, junction cloning, and fish investigations. the events occurred very recently in human genome evolution as demonstrated by sequence analysis of different alleles and the single location of the ancestral site at chromosome 17qter in chimpanzee and orangutan. the domain successfully colonized most 1p, 5q, and 6q chromosome ends and is al ... | 1998 | 9722938 |
| simultaneous estimation of all the parameters of a stepwise mutation model. | minisatellite and microsatellite are short tandemly repetitive sequences dispersed in eukaryotic genomes, many of which are highly polymorphic due to copy number variation of the repeats. because mutation changes copy numbers of the repeat sequences in a generalized stepwise fashion, stepwise mutation models are widely used for studying the dynamics of these loci. we propose a minimum chi-square (mcs) method for simultaneous estimation of all the parameters in a stepwise mutation model and the a ... | 1998 | 9725863 |
| residual lateral wall defects following sinus grafting with recombinant human osteogenic protein-1 or bio-oss in the chimpanzee. | sinus grafting procedures are a viable means of ensuring adequate bone for the placement of dental implants in the posterior maxilla. in the quest to improve predictability and accelerate the time line toward receiving a final prosthesis, researchers have turned to recombinant human proteins like osteogenic protein-1 for the potential to therapeutically enhance bone formation. bilateral sinus augmentations were performed in 15 adults chimpanzees to evaluate treatment with different doses of the ... | 1998 | 9728105 |
| spontaneous leprosy in a wild-caught cynomolgus macaque. | naturally occurring mycobacterium leprae has been previously documented in only two species of nonhuman primates from west africa--the chimpanzee and the sooty mangabey. we report here the first known case of spontaneous leprosy in an asian macaque. a wild-caught cynomolgus macaque imported from the philippines developed a reaction to a tuberculin skin test after 3 years at the california regional primate research center (crprc), university of california-davis, davis, california, u.s.a. biopsies ... | 1998 | 9728446 |
| shadows on a changing landscape: comparing nesting patterns of hominids and chimpanzees since their last common ancestor. | studying the evolution of nesting behavior within the human-chimpanzee clade is problematic because evidence is sparse and difficult to interpret. lacking a fossil or archaeological record for proto-chimpanzees, reconstructions of the antecedents of modern chimp nesting patterns can be reconstructed only from careful studies of variation in current chimpanzee and bonobo nesting patterns within the context of spatial and temporal landscape parameters. the ethology of nesting also provides an impo ... | 1998 | 9730215 |
| evolution of the primate androgen receptor: a structural basis for disease. | androgen effects mediated by the androgen receptor (ar) are essential for male reproductive development and virilization. comparison of ar dna coding sequence from five primate species, homo sapiens (human), pan troglodytes (chimpanzee), papio hamadryas (baboon), macaca fascicularis (macaque), and eulemur fulvus collaris (collared brown lemur), supports their phylogeny with complete conservation of the dna and steroid binding domain protein sequence. a linear increase in trinucleotide repeat exp ... | 1998 | 9732460 |
| maxillary sinus augmentation in the non-human primate: a comparative radiographic and histologic study between recombinant human osteogenic protein-1 and natural bone mineral. | the posterior maxilla has traditionally been one of the most difficult areas to successfully place dental implants due to poor bone quality and close approximation to the maxillary sinus. sinus augmentation procedures have become a viable means of assuring adequate bone for the placement of dental implants in this area. however, with the techniques currently employed, a considerable variation in the quality of bone attained with the sinus augmentation procedure exists. the purpose of this in viv ... | 1998 | 9736374 |
| histological changes of concurrent hepatitis c virus infection in asymptomatic hepatitis b virus patients. | in chimpanzees and in vitro cell culture studies, hepatitis c infection has been shown to suppress hepatitis b virus expression. in addition, hepatitis c infection can cause much more severe liver disease in patients chronically infected with hepatitis b virus. the aims of the present study were to determine the prevalence of hepatitis c infection in asymptomatic chronic hepatitis b hong kong chinese patients and the histological changes and hepatic expression of hepatitis b virus and hepatitis ... | 1998 | 9737572 |
| technical note: modeling primate occlusal topography using geographic information systems technology. | most functional analyses of primate tooth form have been limited to linear or area measurements. such studies have offered but a limited glimpse at differences in occlusal relief among taxa. such differences in dental topography may relate to tooth function and, so, have considerable implications for the inference of diet from fossil teeth. in this article, we describe a technique to model and compare primate molars in three dimensions using geographic resources analysis support system (grass) s ... | 1998 | 9740307 |
| perspectives for a hepatitis c virus vaccine. | natural hepatitis c virus (hcv) infection elicits poor immunity. although hcv proteins elicit immune responses in virtually all cases of infection, the great majority of hcv infections become chronic. currently, no vaccine is available for hcv despite an estimated incidence of approximately 50000 new cases per year in the usa alone. | 1998 | 9741644 |
| evolution of chromosome y in primates. | we have investigated, by fluorescence in situ hybridization (fish), the cytogenetic evolution of the y chromosome in primates using 17 yeast artificial chromosomes, representative of the y-specific euchromatic region of the human chromosome y. the fish experiments were performed on great apes (homo sapiens, pan troglodytes, gorilla gorilla and pongo pygmaeus pygmaeus), and on two old world monkeys species as an outgroup (cercopitecidae macaca fascicularis and papio anubis). the results showed th ... | 1998 | 9745049 |
| molecular phylogenetics of the hominoid y chromosome. | the human y-chromosome plays a central role in sex determination, and is composed of dna sequences homologous to the y-chromosome, families of y-specific repetitive dna sequences, and single copy sequences. we investigated the chromosomal location of y-specific dna sequences, in the chimpanzee (pan troglodytes), gorilla (gorilla gorilla), and orangutan (pongo pygmaeus) by the fluorescence in situ hybridization (fish) technique. the yq subtelomeric dna sequences (dys427) have been observed to be ... | 1998 | 9747032 |
| a mutation in human cmp-sialic acid hydroxylase occurred after the homo-pan divergence. | sialic acids are important cell-surface molecules of animals in the deuterostome lineage. although humans do not express easily detectable amounts of n-glycolylneuraminic acid (neu5gc, a hydroxylated form of the common sialic acid n-acetylneuraminic acid, neu5ac), it is a major component in great ape tissues, except in the brain. this difference correlates with lack of the hydroxylase activity that converts cmp-neu5ac to cmp-neu5gc. here we report cloning of human and chimpanzee hydroxylase cdna ... | 1998 | 9751737 |
| characterization and distribution of mhc-dpb1 alleles in chimpanzee and rhesus macaque populations. | allelic diversity at the nonhuman primate mhc-dpb1 locus was studied by determining exon 2 nucleotide sequences. this resulted in the detection of 17 chimpanzee (pan troglodytes), 2 orangutan (pongo pygmaeus) and 16 rhesus macaque (macaca mulatta) alleles. these were compiled with primate mhc-dpb1 nucleotide sequences that were published previously. based upon the results, a sequence specific oligotyping method was developed allowing us to investigate the distribution of mhc-dpb1 alleles in dist ... | 1998 | 9757948 |
| localization of fcgr1 encoding fcgamma receptor class i in primates: molecular evidence for two pericentric inversions during the evolution of human chromosome 1. | the human high-affinity receptor for immunoglobulin g, fcgammari (fcgr1), is encoded by a family of three genes that share over 95% sequence homology. curiously, the three genes in this recently duplicated gene family flank the centromere of human chromosome 1, with fcgr1b located at 1p12 and both fcgr1a and fcgr1c located at 1q21. we have previously speculated that a pericentric inversion could account for the separation of the genes in the fcgr1 family and explain their current chromosomal loc ... | 1998 | 9763663 |