| the significance of infections with two types of viral hepatitis demonstrated by histologic features in chimpanzees. | in view of the recognized importance of necroinflammatory episodes in chronic hepatitis b virus (hbv) infection, chimpanzees, either hbv surface antigen (hbsag) carriers or noninfected (naive), were infected with other primary hepatotropic viruses to evaluate histologic alterations and changes in virologic and biochemical markers of infection. the advantages of studies on chimpanzees are the availability of serial biopsy specimens and the viral type-specific histologic lesions, not as well recog ... | 1990 | 2106549 |
| a cd4 domain important for hiv-mediated syncytium formation lies outside the virus binding site. | hiv infection of chimpanzees results in a chronic viremia unaccompanied by the ultimately fatal immunodeficiency that marks hiv infection in man. we show here that expression of hiv envelope proteins allows syncytium formation between cells expressing human but not chimpanzee or macaque cd4. we find that the cd4 sequences regulating cell fusion lie outside the recognized virus binding site; in the simplest exchange, chimpanzee cd4 bearing human residue 87 supports syncytium formation, while huma ... | 1990 | 2107024 |
| dna hybridization evidence of hominoid phylogeny: a reanalysis of the data. | sibley and ahlquist (1984, 1987) presented the results of a study of 514 dna-dna hybrids among the hominoids and old world monkeys (cercopithecidae). they concluded that the branching order of the living hominoid lineages, from oldest to most recent, was gibbons, orangutan, gorilla, chimpanzees, and human. thus, a chimpanzee-human clade was indicated, rather than the chimpanzee-gorilla clade usually suggested from morphological evidence. the positions of the gibbon and orangutan branches in the ... | 1990 | 2109085 |
| dna hybridization as a guide to phylogeny: chemical and physical limits. | the technique of forming interspecific dna heteroduplexes and estimating phylogenetic distances from the depression in their duplex melting temperature has several physical and chemical constraints. these constraints determine the maximum phylogenetic distance that may be estimated by this technique and the most appropriate method of analyzing that distance. melting curves of self-renatured single copy primate dnas reveal the presence of components absent from the renaturation products of exactl ... | 1990 | 2109086 |
| primate evolution at the dna level and a classification of hominoids. | the genetic distances among primate lineages estimated from orthologous noncoding nucleotide sequences of beta-type globin loci and their flanking and intergenic dna agree closely with the distances (delta t50h values) estimated by cross hybridization of total genomic single-copy dnas. these dna distances and the maximum parsimony tree constructed for the nucleotide sequence orthologues depict a branching pattern of primate lineages that is essentially congruent with the picture from phylogeneti ... | 1990 | 2109087 |
| relationship between lectin binding properties and the expression of blood group abh antigens in vascular endothelia and red blood cells from 18 primate species. | the reactivity was examined of horseradish peroxidase labelled ulex europaeus agglutinin-i (uea-i) and griffonia simplicifolia agglutinin i-b4 (gsai-b4) with red blood cells and vascular endothelium in formalin-fixed, paraffin embedded tissues from 18 primate species. the expression of blood group abh antigens in these cells as well as secretions from other tissues was also examined by the indirect immunoperoxidase method using monoclonal anti-abh antibodies as primary antibodies. in prosimians ... | 1990 | 2109743 |
| [primates in the study of hepatitis viruses]. | there is no a conventional tissue culture system for the propagation of the hepatitis viruses and only some of them can be maintain in continuous cell culture in particular conditions. a transmissibility of hepatitis is limited to primates. the narrow host specificity may help to establish the classification of the hepatitis viruses and their mode of transmission. moreover, the primate animal model provided the most accessible source of viruses and for clinical reasons presents the only opportun ... | 1990 | 2110646 |
| pharmacokinetics in chimpanzees of recombinant human tissue-type plasminogen activator produced in mouse c127 and chinese hamster ovary cells. | pharmacokinetics of recombinant tissue-type plasminogen activator (rt-pa) produced in mouse c127 cells (t-pa(c127] and chinese hamster ovary cells (t-pa(cho] was investigated in chimpanzees. rt-pa was administered via a constant rate i.v. infusion for 60 min, and t-pa concentration and activity in plasma were measured during and after infusion. the noncompartmental parameters were calculated according to the moment analysis method, and a population pharmacokinetic analysis was performed to obtai ... | 1990 | 2110870 |
| monoclonal antibodies directed against human rh antigens in tests with the red cells of nonhuman primates. | monoclonal antibodies against rh related antigens on human red cells often crossreact with the red cells of the highest subhuman primate species. depending on specificity of antibody, the species tested, and technique used, these reactions can be either species-specific or type specific. in tests with chimpanzee red cells, some of the latter type reactions have specificities related to the r antigen of the r-c-e-f blood group system of chimpanzee; specificities of some others seem to be unrelate ... | 1990 | 2111136 |
| expression of infectious viral particles by primary chimpanzee hepatocytes isolated during the acute phase of non-a, non-b hepatitis. | liver wedge biopsies were obtained from chimpanzees during the acute phase of experimental non-a, non-b hepatitis infections. primary chimpanzee hepatocytes were maintained for over 4 weeks in vitro with a serum-free medium supplemented with growth factors and hormones. the de novo synthesis and secretion of plasma proteins characteristic for differentiated primate hepatocytes were sustained under these culture conditions. immunocytochemical staining for a non-a, non-b hepatitis-associated antig ... | 1990 | 2111839 |
| enterically-transmitted non-a, non-b hepatitis. | more than 50% of acute viral hepatitis occurring in some developing countries appears to be unrelated to infection by hav or hbv and accumulating evidence suggests that a high proportion of this non-a, non-b hepatitis (nanb) is enterically transmitted. epidemics or outbreaks of enterically-transmitted nanb (et-nanb) have been documented in the soviet union, nepal, burma, pakistan, india, borneo, somalia, sudan, ivory coast, algeria, and mexico. these outbreaks primarily affect young to middle-ag ... | 1990 | 2116213 |
| detection of hepatitis b virus dna in serum by polymerase chain reaction. application for clinical diagnosis. | standard methods of virus dna detection using the polymerase chain reaction can be time consuming and can involve multiple steps in which contamination with exogenous dna can occur. therefore, we developed a simplified method for detecting hepatitis b virus dna in serum. the main advantages of this method are that it can be performed rapidly, consists of only several steps, and has a false positive rate of less than 0.1% in our laboratory. in testing serial samples from five chimpanzees experime ... | 1990 | 2116344 |
| early events in hepatitis c virus infection of chimpanzees. | the cytoplasmic antigen and ultrastructural changes we described previously for chimpanzees (pan troglodytes) infected with hepatitis c virus (hcv) or with hepatitis d virus have recently been shown to be indirect measures of viral replication and appear to represent a host response to the expression or action of interferon. the time of appearance of these changes in hepatocytes during hcv infection, when compared with similar changes in hepatitis d virus infection, suggests a very early replica ... | 1990 | 2117282 |
| production of immunoglobulin a protease by streptococcus pneumoniae from animals. | human isolates of streptococcus pneumoniae tested by traditional immunochemical methods produce a protease that cleaves human immunoglobulin a1 (iga1) into fab and fc fragments. the protease may be an important virulence factor, but studies of its pathogenetic significance have been hampered by lack of a suitable animal model. since s. pneumoniae is a respiratory pathogen for several species of animals, we sought to determine whether isolates of this organism from animals with pneumococcal infec ... | 1990 | 2117567 |
| mitochondrial dna evolution in primates: transition rate has been extremely low in the lemur. | based on mitochondrial dna (mt-dna) sequence data from a wide range of primate species, branching order in the evolution of primates was inferred by the maximum likelihood method of felsenstein without assuming rate constancy among lineages. bootstrap probabilities for the maximum likelihood tree topology among alternatives were estimated without performing a maximum likelihood estimation for each resampled data set. variation in the evolutionary rate among lineages was examined for the maximum ... | 1990 | 2120449 |
| biologic heterogeneity of human immunodeficiency virus type 2 (hiv-2) strains. | seven hiv-2 isolates recovered from peripheral blood mononuclear cells (pbmc) of patients from the ivory coast have been biologically characterized. all seven strains replicated well in primary human lymphocyte and macrophage cultures and in established human t cell lines. they showed differences in infectivity and replicating ability in primary pbmc cultures from chimpanzees, rhesus macaques, and baboons. moreover, variations in levels of virus replication in pbmc from 13 seronegative donors we ... | 1990 | 2120848 |
| comparative morphology of the lateral meniscus of the knee in primates. | the morphology of the lateral meniscus has been studied in a series of 316 non-human primates, representative of 43 genera. the lateral meniscus has a crescentic shape in prosimii, in platyrrhinii (new world monkeys) and in pongo pygmaeus. the lateral meniscus is disc-shaped, with a central foramen, in catarrhinii (old world monkeys), in hylobates, in gorilla and in pan troglodytes. in man, the lateral meniscus has a crescentic shape. discoid lateral menisci are reported as anomalies in man; the ... | 1990 | 2123845 |
| the evolutionary watershed of susceptibility to gonococcal infection. | gonococci do not cause genital infection in any convenient experimental animal, but all too easily cause genital infection in humans. to determine the 'evolutionary watershed' of gonococcal infections (the point on the evolutionary tree at which susceptibility to gonococcal infection begins) we extended previous studies of the interaction of gonococci with animal oviduct mucosa to include chimpanzees and baboons. gonococci attached to, damaged, and invaded the oviduct (fallopian tube) mucosa of ... | 1990 | 2126057 |
| yeast-expressed p55 precursor core protein of human immunodeficiency virus type 1 does not elicit protective immunity in chimpanzees. | yeast-expressed p55 precursor core protein of human immunodeficiency virus type 1 (hiv-1) was used to immunize chimpanzees. the animals developed high titers of antibodies to p55 as well as to the p24 and p17 mature cleavage products of the core precursor. virus-neutralizing antibodies were not elicited. the induced immune responses did not prevent establishment of hiv-1 infection following challenge of one immunized chimpanzee with live virus. | 1990 | 2127681 |
| neisseria gonorrhoeae colonises the genital tract of oestradiol-treated germ-free female mice. | germ-free balb/c mice treated with oestradiol and inoculated intravaginally with a serum-resistant strain or a freshly isolated, piliated strain of neisseria gonorrhoeae were colonised vaginally. the organisms were recovered intermittently for a month or longer and there was evidence that they could reach the upper genital tract. mice given progesterone and those not treated with either hormone did not become colonised. this is the first evidence of sustained mucosal colonisation in animals othe ... | 1990 | 2129173 |
| potential of primate monoclonal antibodies to substitute for human antibodies: nucleotide sequence of chimpanzee fab fragments. | the nucleotide sequence of the mrna that codes for fab fragments from two chimpanzee monoclonal antibodies has been determined. both antibodies have high affinity and good specificity for digoxin. four domains from the two antibodies have been sequenced: the constant domains of the kappa and lambda light chains, the variable domain of the lambda light chain, and the ch1 domain of the igg1 heavy chain. there are very few differences between the chimpanzee and human sequences; the nucleotide seque ... | 1990 | 2129418 |
| defects in the precore region of hepatitis b virus dna in a plasma pool from carriers seropositive for antibody against e antigen and with infectivity in chimpanzees. | a plasma pool from 12 asymptomatic carriers seropositive for antibody against hepatitis b e antigen (anti-hbe) contained hepatitis b virus (hbv) with chimpanzee infectious doses of 1-100/ml, and another pool from 12 carriers positive for hepatitis b e antigen (hbeag) contained 10(8)/ml doses or more. the hbeag-positive pool contained 10(6)-fold more hbv dna than the anti-hbe-positive pool, reflecting the difference in infectivity in chimpanzees. the precore region sequences of hbv dna in the two ... | 1990 | 2129834 |
| isolation of rapidly evolving genomic sequences: construction of a differential library and identification of a human dna fragment that does not hybridize to chimpanzee dna. | a differential library enriched in rapidly evolving human genomic sequences was obtained by phenol-enhanced hybridization of human genomic dna with an excess of chimpanzee dna. a dna fragment 110 bp in length that did not hybridize to either chimpanzee or other primate dna was identified in this library. it was shown to be a substantially diverged member of the human beta satellite family of tandem repeats. the genomic sequences homologous to the fragment were located on the short arms of human ... | 1990 | 2133068 |
| a 36 nucleotide deletion mutation in the coding region of the ns1 gene of an influenza a virus rna segment 8 specifies a temperature-dependent host range phenotype. | previously a spontaneous 36 nucleotide deletion in the coding region of ns1 was detected in the ns gene of a reassortant virus (cr43-3) recovered from a dual infection by the influenza a/ann arbor/6/60 cold-adapted (ca) mutant and wild-type (wt) influenza a/alaska/6/77 (h3n2). the hemagglutinin, neuraminidase and ns genes were derived from the wild type virus parent while the other 5 genes were derived from the ca parent. the cr43-3 reassortant virus exhibited: (i) a host range (hr) phenotype, i ... | 1990 | 2138396 |
| human immunodeficiency virus infection of monocytes: relationship to fc-gamma receptors and antibody-dependent viral enhancement. | antibodies that augment human immunodeficiency virus (hiv) infectivity of monocytes through fc receptor (fcr) type iii for igg have been found in the blood of sero-positive patients and immunized chimpanzees. this study investigated the effect of acute and chronic hiv infection, as well as protein kinase c activators capable of up-regulating latent hiv, on the expression of these receptors. in addition, the frequency of this antibody-dependent enhancement (ade) phenomenon was estimated using pur ... | 1990 | 2143169 |
| techniques and significance of gamete collection and storage in the great apes. | rectal probe electroejaculation (rpe) is the most frequently used method for semen recovery in the great apes. artificial insemination has been successful in the chimpanzee and gorilla. oocytes can be recovered using laparoscopic techniques similar to those used in human medicine. at this time there has been no successful in vitro fertilization with birth of an infant in the great apes. semen can be successfully frozen in the apes, as documented by recovery of motility of sperm after thawing. pr ... | 1990 | 2147215 |
| neutralization and enhancement of in vitro and in vivo hiv and simian immunodeficiency virus infections. | over the past year significant progress has been made in mapping those regions of the hiv-1 envelope glycoproteins involved in virus neutralization and virus enhancement. these functional, antigenic domains of the gp160 are illustrated in fig. 1. the role of neutralization in vaccine development is still unresolved, although high-titer antibody to the v3 loop of hiv-1 appears to be correlated with the ability to prevent hiv-1 infection by the homologous strain in chimpanzees. therefore, the mech ... | 1990 | 2152561 |
| novel use of a chimpanzee pseudogene for chromosomal mapping of human cytochrome c oxidase subunit iv. | we have isolated a chimpanzee processed pseudogene for subunit iv of cytochrome c oxidase (cox; ec 1.9.3.1) by screening a chimpanzee genomic library in lambda charon 32 with a bovine liver cdna encoding cox subunit iv (cox iv), and localized it to a 1.9-kb hindiii fragment. southern-blot analysis of genomic dna from five primates showed that dnas from human, gorilla, and chimpanzee each contained the 1.9-kb pseudogene fragment, whereas orangutan and pigtail macaque monkey dna did not. this resu ... | 1990 | 2157630 |
| tool use and tool making in wild chimpanzees. | reported incidences of tool use and tool making for three wild chimpanzee populations increase from mahale (12 and 3 types of use and making, respectively), gombe (16 and 3) to taï (19 and 6). sticks are commonly used and prepared at all three sites. however, taï chimpanzees seem to perform more modifications on the material before using it. they are also the only chimpanzees seen to pound objects with tools and to combine two different tool uses to get access to one food item. tool making is th ... | 1990 | 2157651 |
| in vitro susceptibility of t lymphocytes from chimpanzees (pan troglodytes) to human herpesvirus 6 (hhv-6): a potential animal model to study the interaction between hhv-6 and human immunodeficiency virus type 1 in vivo. | the in vitro susceptibility of several nonhuman primate species to human herpesvirus 6 (hhv-6) was investigated. only peripheral blood mononuclear cells from chimpanzees (pan troglodytes) were found permissive to productive infection by hhv-6, indicating that the host range of hhv-6, albeit limited, may not be restricted to homo sapiens. however, natural hhv-6 infection in chimpanzees, as well as in the other species tested, could not be documented by serological analysis. as previously observed ... | 1990 | 2159541 |
| intracytoplasmic crystalline inclusions in the hepatocytes of humans and chimpanzees. | intracytoplasmic crystalline inclusions (ccis) were observed in liver biopsy specimens taken from three patients and three chimpanzees. ccis are rare in human hepatocytes and have never been described in chimpanzees. all three human cases were connected with alcoholic liver disease; no viral infection was noted. the histologies of the two liver biopsy specimens obtained from healthy chimpanzees were normal, but hepatitis b virus (hbv) infection was demonstrated in the third case by immunohistoch ... | 1990 | 2166371 |
| characterization and biological properties of a hepatitis b virus isolated from a patient without hepatitis b virus serologic markers. | we have developed a rapid method to characterize genomic diversity of low-level hepatitis b and related viral agents after their identification in serum by high-affinity hbsag-antibody monoclonal antibody capture and subsequent polymerase chain reaction amplification. serum from an individual with chronic liver disease and without hepatitis b virus serological markers but reactive by monoclonal antibody capture/polymerase chain reaction amplification was inoculated into a chimpanzee. after inocu ... | 1990 | 2167867 |
| a transpositionally and transcriptionally competent alu subfamily. | dna base sequence comparisons indicate that a subfamily of recently transposed human alu repeats are distinguished from most alu repeats by diagnostic sequence differences. using an oligonucleotide hybridization probe that incorporates these sequence features, we found that there was an expansion of this alu subfamily following the divergence of humans and african apes. this oligonucleotide was used to select human genomic clones containing representatives of this subfamily. one representative m ... | 1990 | 2169023 |
| hepatitis c viral cdna clones isolated from a healthy carrier donor implicated in post-transfusion non-a, non-b hepatitis. | using a specific hepatitis c virus (hcv) antibody assay, positive blood donors responsible for the transmission of post-transfusion non-a, non-b hepatitis (pt-nanbh) were identified. cdna fragments were isolated from one of the plasma samples of such healthy hcv carriers by using polymerase chain reactions. nucleotide (nt) sequence analyses of the cdna from three different regions of the viral genome revealed that they were derived from a japanese hcv isolate that was similar but not identical t ... | 1990 | 2170237 |
| isolation and purification of a non-a, non-b hepatitis-associated microtubular aggregates protein. | blood-borne type non-a, non-b (nanb) hepatitis-associated microtubular aggregates protein was isolated and partially sequenced. the microtubular aggregates were isolated from the hepatocytes of nanb-infected chimpanzees and were found to have a buoyant density in sucrose solution of 1.21 to 1.23 g/ml. a single protein, recognized by our anti-microtubular aggregates monoclonal antibodies, was found to have an mr of 44,000 (p44). this p44 protein was not found in uninfected chimpanzees. we determi ... | 1990 | 2170569 |
| cloning, sequencing and expression in escherichia coli of cdna for a non-a, non-b hepatitis-associated microtubular aggregates protein. | a 1.7 kb cdna encoding a novel antigen (p44; apparent mr 44k) associated with non-a, non-b (nanb) hepatitis, was isolated from the hepatic cdna library of a chimpanzee infected with nanb hepatitis. the library was screened with a monoclonal antibody against this antigen. the cdna cloned contained an open reading frame encoding a 444 amino acid protein with an mr calculated to be 50,468. the cdna hybridized to a 1.9 kb mrna obtained from chimpanzee hepatocytes infected with either the nanb or hep ... | 1990 | 2170570 |
| antibodies to the rnase h domain of hepatitis b virus p protein are associated with ongoing viral replication. | antibodies against the rnase h domain of human hepatitis b virus p protein(s) are frequent markers of acute and chronic virus infection (t. weimer, k. weimer, z.-x. tu, m.-c. jung, g. r. pape, and h. will, j. immunol. 143:3750-3756, 1989). in the present study, these antibodies were determined in serial serum samples of experimentally infected chimpanzees and naturally infected human patients with acute and chronic hepatitis b virus infection. anti-p antibodies were found in the sera of both chi ... | 1990 | 2170693 |
| the 5'-terminal sequence of the hepatitis c virus genome. | the 5'-terminal sequence of the genome of hepatitis c virus (hcv) was determined for two distinct hcv strains in human and chimpanzee carriers. it had a 5'-noncoding region of at least 324 nucleotides, well preserved by the two strains with a high homology (99.1%), followed by 1348 nucleotides that continued to the documented sequence of prototype hcv spanning 7310 nucleotides (european patent application #88310922.5). based on these results, hcv is considered to possess an uninterrupted open re ... | 1990 | 2170712 |
| [the hepatitis c virus--principal causative agent in non-a, non-b hepatitis]. | the diagnosis of non-a, non-b (nanb) hepatitis was based on the exclusion of hepatitis a and b infection and other known causes of hepatitis, such as other viruses, alcohol and toxic effects. more recently, an rna has been isolated from a nanb-infected chimpanzee serum and with its aid a polypeptide antigen was produced by molecular biological methods. antibodies to this antigen--as part of the infectious agent, called hepatitis c virus (hcv)--were detected in the sera of infected patients. stud ... | 1990 | 2170894 |
| [classification of retroviruses]. | the retroviridae comprise a large number of viruses. in both nature and laboratories these viruses are associated with numerous diseases, including rapid or long latency malignancies, neurological disorders and immunodeficiency. the replication cycle is characterized by integration of the viral dna into the host's genome after the reverse transcriptase copied the viral rna into dna. the discovery of human retroviruses had a late start. it was not until 1980 that the first oncovirus, the human t- ... | 1990 | 2173126 |
| report of a who informal consultation on animal models for evaluation of drugs and vaccines for hiv infection and aids. w.h.o., geneva, 14-15 september 1989. | the use of animal models in the preclinical evaluation of anti-hiv drugs and vaccines was discussed at an informal consultation at world health organization headquarters in geneva, 14-15 september 1989. the consultation was attended by six experts from four countries. hiv animal models, other lentivirus/animal models and oncornavirus/animal models were discussed, and their advantages and disadvantages were compared to hypothetical ideal hiv/animal models for preclinical evaluation of anti-hiv dr ... | 1990 | 2175206 |
| the putative nucleocapsid and envelope protein genes of hepatitis c virus determined by comparison of the nucleotide sequences of two isolates derived from an experimentally infected chimpanzee and healthy human carriers. | cdna fragments of a 5'-terminal region of the hepatitis c virus (hcv) genome were isolated by the reverse polymerase chain reaction from rna extracted from plasma samples of healthy japanese carriers. their nucleotide sequence was compared with that of the original isolate which had been passaged twice in chimpanzees. no deletions or insertions were observed between the two sequences in the regions examined. both the 5' untranslated and putative nucleocapsid (core) protein regions were highly co ... | 1990 | 2177094 |
| [non-a, non-b hepatitis: hepatitis c]. | non-a, non-b hepatitis (nanb), whether following the transfusion of blood products or occurring sporadically without percutaneous exposure, is complicated in approximately 50% of cases by the development of chronic hepatitis. emerging as a consistent observation is the insidious progression of such cases of chronic nanb hepatitis to cirrhosis. among patients with chronic nanb hepatitis followed for up to 10 years, cirrhosis is demonstrable in 20%. in may, 1988, the identification of the agent of ... | 1990 | 2177314 |
| three independent insertions of retrovirus-like sequences in the haptoglobin gene cluster of primates. | the human haptoglobin two-gene cluster (hp-hpr) contains two retrovirus-like elements. one (rtvl-ia) is in the first intron of the hpr gene, and the second (rtvl-ic) is at the 3'-end of the gene cluster. the chimpanzee three-gene cluster (hp-hpr-hpp) contains an additional, third copy (rtvl-ib) in the intergenic region between hpr and hpp. rtvl-ia and rtvl-ib are essentially full size and have the general structure, 5'-ltr-gag-pol-env-3'-ltr, while rtvl-ic lacks about one-third of its 5'-part. a ... | 1990 | 2177446 |
| infection of chimpanzees with the uganda i/cdc strain of plasmodium malariae. | nine splenectomized chimpanzees were infected with the uganda i/cdc strain of plasmodium malariae. two had no history of previous malarial infection, whereas 6 had been infected with p. vivax and 1 with p. vivax and p. ovale. the animals with no previous infection had maximum parasitemias of 8,740 and 10,800/mm3. the other animals had maximum parasite counts of 930-75,700/mm3. anopheles freeborni, an. stephensi, an. dirus, an. maculatus, an. quadrimaculatus, an. culicifacies, an. arabiensis, and ... | 1990 | 2180332 |
| evolution of the class ii major histocompatibility complex alleles in higher primates. | we have shown that chimpanzees and gorillas have drb alleles very similar to those of humans. the existence of similar drb alleles in the different species of higher primates cannot be accounted for by convergent evolution of unrelated alleles that arose independently after the speciation. we therefore conclude that ancestral drb alleles, that had existed before the speciation, were transmitted to the ancestors of humans, chimpanzees, and gorillas. this conclusion indicates that the diversificat ... | 1990 | 2180812 |
| genetic organization of a chimpanzee lentivirus related to hiv-1. | simian immunodeficiency viruses have been isolated from four species of monkey, the 'captive' macaque and mangabey and the 'feral' african green monkey and mandrill. while none of these viruses is a replica of hiv-1, the macaque and mangabey viruses represent correct genetic models for hiv-2, possessing exactly the same complement of genes. recently a lentivirus has been identified in two wild chimpanzees (pan troglodytes troglodytes) in gabon, west equatorial africa, and isolated from one of th ... | 1990 | 2188136 |
| protection of chimpanzees from infection by hiv-1 after vaccination with recombinant glycoprotein gp120 but not gp160. | the development of a vaccine to provide protective immunity to human immunodeficiency virus type 1 (hiv-1), the virus causing aids, would be the most practical method to control its spread. subunit vaccines consisting of virus envelope glycoproteins, produced by recombinant dna technology, are effective in preventing viral infections. we have now used this approach in the development of a candidate aids vaccine. chimpanzees were immunized with recombinant forms of the hiv-1 glycoproteins gp120 a ... | 1990 | 2190095 |
| human monoclonal antibody ha6d3, a candidate for treatment of leukaemia? in vitro reactivity of ha6d3 with leukaemic cells and in vivo applications in a chimpanzee. | the human monoclonal antibody ha6d3 of the igm type was used to stain malignant lymphoma cells from peripheral blood in flow cytometry and from cryosections of lymph nodes using the immunoperoxidase technique. it was found to react with peripheral white blood cells of all 12 cases of leukaemia and with lymph node cells of seven out of 11 b cell lymphomas and with the one t cell lymphoma tested so far. for in vivo experiments a batch of 70 mg ha6d3 was purified and 6 mg ha6d3 was injected intrave ... | 1990 | 2200495 |
| tool use in cebus. | this paper summarizes early anecdotal information and systematic studies of tool use in capuchin monkeys (cebus spp.). tool use in capuchins is neither context specific nor stereotyped. the success of capuchins in using tools and in exploiting a variety of food resources in the wild derives from several factors: their manipulative abilities, interest in external objects and a tendency to explore the environment. in using tools, capuchins are similar to apes and more proficient than other monkey ... | 1990 | 2202616 |
| processing of form stimuli presented unilaterally in humans, chimpanzees (pan troglodytes), and monkeys (macaca mulatta). | visual forms were unilaterally presented using a video-task paradigm to 10 humans, 3 chimpanzees, and 2 rhesus monkeys to determine whether hemispheric advantages existed in the processing of these stimuli. both accuracy and reaction time served as dependent measures. for the chimpanzees, a significant right hemisphere advantage was found within the first 3 test sessions. the humans and monkeys failed to show a hemispheric advantage as determined by accuracy scores. analysis of reaction time dat ... | 1990 | 2206427 |
| familial incidence of multiple births in a colony of chimpanzees (pan troglodytes). | this paper describes the incidence of multiple births in the yerkes chimpanzee colony for a period of about 63 years. pedigrees are presented for all multiple births. they demonstrate the recurrence of twins in relatively few family lines which can be traced back to a small number of ancestors. the findings suggest that twinning is a family trait in chimpanzees and they support the hypothesis that the incidence of multiple births is genetically influenced in this colony. in addition, a relativel ... | 1990 | 2213855 |
| processing, assembly, and immunogenicity of human immunodeficiency virus core antigens expressed by recombinant vaccinia virus. | recombinant vaccinia viruses that contained regions of the gag-pol open reading frames of human immunodeficiency virus type 1 (hiv-1) were constructed. cells infected with recombinants containing both gag and protease genes expressed and processed hiv gag antigens efficiently. processing was much reduced in cells infected with recombinants containing only gag, but not the protease gene. however, significant amounts of p41 were produced by protease-defective recombinants. this protein was immunor ... | 1990 | 2219727 |
| phylogeny and molecular evolution in primates. | statistical methods for estimating the branching order and the branching dates from dna sequence data, taking into account of the rate variation among lineages, are reviewed. an application of the methods to data from primates suggests that chimpanzee is the closest relative of man, and further suggests that these two species diverged about 4-5 million years ago. | 1990 | 2223159 |
| effects of membrane lipid and fluidity modifications on hiv-1 infectibility of primate lymphocytes in vitro. | although most non-human primates, except the chimpanzee and the gibbon in vivo are not infectible by hiv-1, lymphocytes of several of these species can be infected by hiv-1 in vitro. in order to investigate whether the in vitro infectibility of primate lymphocytes might be attributed to plasma membrane adaptation processes or to serum factors, we compared hiv-1 infectibility of cultivated peripheral blood lymphocytes of macaques and of baboons on day one and on day ten of cultivation. these data ... | 1990 | 2224064 |
| [a fragment of human dna lacking hybridization with chimpanzee dna]. | | 1990 | 2226139 |
| hepatitis b virus dna detection and comparison with hepatitis b surface antigen. | hepatitis b surface antigen (hbsag) has been used for the detection of hepatitis b virus (hbv). recently, hbv detection using the polymerase chain reaction (pcr) has been shown to be a direct measure of complete virions and to be potentially a very sensitive method. therefore, we attempted to analyze the relationship between hbsag detection and hbv dna assay by pcr. we tested hbv dna by a modification of the pcr technique in serial sera from five chimpanzees experimentally infected with hbv and ... | 1990 | 2227267 |
| comparison of auditory functions in the chimpanzee and human. | absolute thresholds for pure tones, loudness, frequency and intensity difference thresholds and the resonance of the external auditory meatus were measured in chimpanzees and compared with those in humans. chimpanzees were more sensitive than humans to frequencies higher than 8 khz but less sensitive to frequencies lower than 250 hz and 2- to 4-khz tones. difference thresholds for frequency and intensity were greater in chimpanzees than in humans. the resonance of the external ear was about the ... | 1990 | 2227723 |
| molecular genetic divergence of orang utan (pongo pygmaeus) subspecies based on isozyme and two-dimensional gel electrophoresis. | the orang utan (pongo pygmaeus), as currently recognized, includes two geographically separated subspecies: pongo pygmaeus pygmaeus, which resides on borneo, and p. p. abelii, which inhabits sumatra. at present, there is no known route of gene flow between the two populations except through captive individuals which have been released back into the wild over the last several decades. the two subspecies are differentiated by morphological and behavioral characters, and they can be distinguished b ... | 1990 | 2230076 |
| [detection of serum hepatitis b virus dna using the polymerase chain reaction assay]. | we compared the sensitivity of the polymerase chain reaction (pcr) assay to that of slot blot hybridization for detecting hepatitis b virus (hbv) dna in the serum of a chimpanzee infected with hbv and 52 patients. also, we utilized a rapid pcr procedure for the detection: viral dna was released from virions by incubating serum with naoh. after a primary pcr amplification, the sample was reamplified using a second set of primer pairs (pcr/pcr). in the chimpanzee, hbv dna was detected 3 weeks earl ... | 1990 | 2232264 |
| characterization of a monoclonal crossreacting anti-a, b antibody. | ten monoclonal antibodies (mabs) have been produced from mouse-mouse hybridomas raised to dispase-treated human group ab red blood cells (rbcs). one of these antibodies, t-1435a, reacted with the rbcs of the human group a, b, and ab, but not to the rbcs of group o. the reactivity of t-1435a was specific to a single anti-a, b but not to a mixture of an anti-a and an anti-b. also, t-1435a reacted strongly with protease- and neuraminidase-treated rbcs, and the susceptibility of its corresponding an ... | 1990 | 2232333 |
| structure and evolution of the u2 small nuclear rna multigene family in primates: gene amplification under natural selection? | the organization of u2 genes was compared in apes, old world monkeys, and the prosimian galago. in humans and all apes (gibbon, orangutan, gorilla, and chimpanzee), the u2 genes were organized as a tandem repeat of a 6-kb element; however, the restriction maps of the 6-kb elements in these divergent species differed slightly, demonstrating that mechanisms must exist for maintaining sequence homogeneity within this tandem array. in old world monkeys, the u2 genes were organized as a tandem repeat ... | 1990 | 2233721 |
| hepatitis b virus propagated in a rat hepatoma cell line is infectious in a primate model. | the human hepatitis b virus (hbv) produced by a rat hepatoma cell line through transfection with hbv dna is infectious in the human primate model--chimpanzee. since hepadnaviruses are known to have an extremely narrow host range, our results support the idea that the host species barrier of hbv infection resides on the penetration/adsorption step rather than any postpenetration intracellular event during the virus life cycle. | 1990 | 2238476 |
| [comparative anatomic studies of the tongue of pan troglodytes (blumenbach, 1799) and other primates. i. the chimpanzee tongue]. | this study was carried out on a comprehensive collection of tongues of pan troglodytes. material of tongues of tupaia glis, microcebus murinus, chirogaleus major, lemur catta, galago crassicaudatus, cebus apella, and macaca mulatta were used for comparison of the different stages of the development of the papilla foliata. the tongue of pan exhibits longitudinal growth correlated with the growth of length of the jaws and individual age. a typical foramen caecum as it occurs in man was gross anato ... | 1990 | 2242823 |
| birth spacing patterns in humans and apes. | comparative studies of birth interval dynamics in wild primates suffer from several problems of analysis and interpretation: (1) the data are always right-censored, (2) sample sizes are usually small, (3) the distribution of birth intervals is expected to be non-normal, (4) early offspring mortality is a confounding variable, and (5) differences in life history (e.g., presence or absence of menopause) can complicate interpretation of the results. a survival analysis designed to minimize these pr ... | 1990 | 2248378 |
| behavioral responsiveness to strangers in young chimpanzees (pan troglodytes). | earlier studies of responses of primate infants to strangers were frequently confounded with separation from the attachment figure and/or removal to an unfamiliar setting. in the present study, young chimpanzees were tested in a familiar setting with a human female caretaker who served as an attachment figure. two strangers were introduced: a human female, approximately the size of the caretaker, who refrained from initiating interactions and a larger human male, who repeatedly approached and in ... | 1990 | 2262174 |
| isolation and amino acid sequences of squirrel monkey (saimiri sciurea) insulin and glucagon. | it was reported two decades ago that insulin was not detectable in the glucose-stimulated state in saimiri sciurea, the new world squirrel monkey, by a radioimmunoassay system developed with guinea pig anti-pork insulin antibody and labeled pork insulin. with the same system, reasonable levels were observed in rhesus monkeys and chimpanzees. this suggested that new world monkeys, like the new world hystricomorph rodents such as the guinea pig and the coypu, might have insulins whose sequences di ... | 1990 | 2263627 |
| the 60 and 63 kda proteolytic peptides of the red cell membrane band-3 protein: their prevalence in human and non-human primates. | three phenotypes based on the polymorphism of band-3 protein from human red cells are described. limited proteolysis of intact red cells from most individuals (homozygotes) yields a peptide of 60 kda, but in some cases (heterozygotes), there is also a 63-kda peptide, and rarely only the single peptide of 63 kda is found. this is the first description of the 63-kda homozygote. the interpretation that the three phenotypes are controlled by two alleles of a single autosomal locus, with no dominance ... | 1990 | 2265824 |
| words: what are they, and do animals have them? | since the word is not a well-defined entity like the sentence, one looks for findings that may help to clarify it. the effect of nonsense words on the young child's sorting of taxonomic versus thematic alternatives is said to be such a finding. a young child given, say, duck as a sample, goose and nest as alternatives, picks nest (thematic alternative), whereas the older child picks goose (taxonomic). however, if told the duck is called "zlt" in croatian, and asked to "find another zlt", the you ... | 1990 | 2282772 |
| animal research in psychology: declining or thriving? | from dialog's psychinfo database the number of studies with 6 species reported in the psychological abstracts was calculated for each year from 1967 to 1988. also, the number of studies with an additional 11 species were calculated for each year from 1973 to 1988. a hand search in the journal of the experimental analysis of behavior and learning and motivation was also conducted to explore trends in studies on 12 species from 1970 to 1987. the numbers of studies on many species (e.g., baboons, b ... | 1990 | 2282783 |
| evidence for rapid selection and deletion of hiv-1 subpopulations in vivo by v3-specific neutralizing antibody: a model of humoral-associated selection. | emergence in two chimpanzees of hiv-1 htlv-iiib variants resistant to neutralization by the pre-existing antibody is described. viruses isolated from the htlv-iiib gp120 vaccinated and challenged animal were more resistant to neutralization, had more heterogenic genomes and showed more pronounced antigenic drift as determined by serotypic neutralization analysis than viruses isolated from the naive infected animal, indicating immune pressure as the selective mechanism. the earliest selecting ant ... | 1990 | 2282990 |
| t cell responses in a sporozoite-immunized human volunteer and a chimpanzee. | we have recently investigated the specificity of t cells induced in a human volunteer and a chimpanzee immunized by multiple exposures to the bites of large numbers of malaria-infected mosquitoes. t cell lines and clones have been obtained from a human volunteer immunized with plasmodium falciparum sporozoites. these cd4+ t cell clones specifically recognize the native circumsporozoite (cs) protein expressed on sporozoites, as well as bacteria- and yeast-derived recombinant falciparum cs protein ... | 1990 | 2283162 |
| detection of hepatitis b virus dna using the polymerase chain reaction technique. | the polymerase chain reaction (pcr) technique has been utilized for the detection of hepatitis b virus (hbv) dna, and several factors related to the selection of primer pairs for the pcr amplification have been demonstrated. the sensitivity of the pcr assay was compared with that of slot-blot hybridization for detecting hbv-dna. analysis by the pcr technique with southern blot hybridization provided a greater than 10(4)-fold increase in sensitivity over the slot-blot hybridization analysis. also ... | 1990 | 2283567 |
| position and orientation of the foramen magnum in higher primates. | the location of the foramen magnum, with respect to the longitudinal axis of the cranium, and its orientation with respect to the frankfurt horizontal, have been studied in a total of 328 modern human and pan crania. the samples were chosen in order to examine the effect of overall size difference on foramen magnum disposition. foramen position (expressed as three indices) and inclination are relatively invariant among the modern human samples, but the foramen magnum is consistently, and statist ... | 1990 | 2301559 |
| the complement component c4 of mammals. | human complement component c4 is coded by tandem genes located in the hla class iii region. the products of the two genes, c4a and c4b, are different in their activity. this difference is due to a degree of 'substrate' specificity in the covalent binding reactions of the two isotypes. mouse also has a duplicated locus, but only one gene produces active c4, while the other codes for the closely related sex-limited protein (slp). in order to gain some insight into the evolutionary history of the d ... | 1990 | 2302180 |
| allelic diversification at the class ii dqb locus of the mammalian major histocompatibility complex. | the allelic diversity at hla class ii loci either arose after the divergence of hominoid lineages or, alternatively, the polymorphism was present before speciation and has been maintained by selection. here, we report the use of oligonucleotide primers to amplify, by the polymerase chain reaction, and sequence the polymorphic second exon of the dqb locus from 11 species, spanning more than 40 million years of mammalian evolution. phylogenetic analysis reveals that of the four human dqb allelic t ... | 1990 | 2308943 |
| morphology of synapses at the base of hair cells in the organ of corti of the chimpanzee. | the synaptic morphology of inner and outer hair cells of the organ of corti of the chimpanzee was evaluated by serial section electron microscopy. the morphology of nerve terminals and synapses at both sites was very similar to that of human and other mammalian species. two types of nerve terminals, nonvesiculated and vesiculated, with distinct synaptic morphology were found. in addition, between some nonvesiculated endings and outer hair cells, a reciprocal synaptic relationship was seen. in su ... | 1990 | 2310138 |
| heat-labile, complement-like factor(s) of animal sera prevent(s) hiv-1 infectivity in vitro. | we studied inactivation of hiv-1 by fresh sera of animals. we found that while fresh sera of humans and chimpanzees (among others) did not have antiviral activity, fresh sera of several other mammals, especially those of rodents and felines, showed a dose-dependent viral-inactivating property against cell-free hiv-1; these sera were also capable of inactivating virus preadsorbed to cells, similar to neutralizing antibody. the activity was destroyed by heating to 56 degrees c, required ca2+ but n ... | 1990 | 2313562 |
| common fragile sites in man and three closely related primate species. | the expression of common fragile sites was studied in peripheral lymphocytes of man, gorilla, chimpanzee, and orangutan after induction with aphidicolin, methotrexate, or fluorodeoxyuridine. as far as the chromosomal localization is concerned, it appears that many of these sites have been highly conserved during primate evolution. however, differences were found in the relative expression of certain sites. in all four species, mapping of approximately 500 lesions disclosed the most breakage-pron ... | 1990 | 2323227 |
| human monoclonal antibodies to the human immunodeficiency virus type 1 (hiv-1) transmembrane glycoprotein gp41 enhance hiv-1 infection in vitro. | three of 16 human monoclonal antibodies (hu-mabs) enhanced human immunodeficiency virus type 1 (hiv-1) infection of mt-2 target cells by means of a mechanism that is dependent on complement. enhanced infections are characterized by an increase in cytopathic effects and antigen synthesis as well as an increase in the production of progeny virus as detected by release of reverse transcriptase activity and infectious virus into the culture medium. analyses by radioimmunoprecipitation, western blot, ... | 1990 | 2326277 |
| identification of human urinary stains by the quotient uric acid/urea nitrogen. | uric acid (ua) and urea nitrogen (un) were determined in urinary stains and the ua/un x 20 values were calculated. the values in human urinary stains were 1.11-4.21, while those in other mammals except some of chimpanzees, were under 0.7, and those in fecal stains of birds were over 80. most of the stains of other human body fluids or plant juices tested contained neither ua nor un, and some contained one, but never the other. ascorbic acid (as) of up to 100 mg/dl in urine did not interfere with ... | 1990 | 2335334 |
| evaluation in chimpanzees of vaccinia virus recombinants that express the surface glycoproteins of human respiratory syncytial virus. | the immunogenicity and protective efficacy of recombinant vaccinia viruses that express the two major protective antigens of human respiratory syncytial virus (rsv), the f and g glycoproteins, were evaluated in chimpanzees. in previous studies in rodents and monkeys the f and g proteins expressed by the same recombinants were highly immunogenic and induced high levels of resistance to rsv replication following subsequent challenge. in contrast, in chimpanzees, a single intradermal immunization i ... | 1990 | 2336876 |
| the presence of pinworms (enterobius sp.) in the mesenteric lymph nodes, liver and lungs of a chimpanzee, pan troglodytes. | this report describes a case of fatal enterobiasis caused by enterobius sp. in the mesenteric lymph nodes, lymphatic vessels of mesentery, blood vessels of the liver and lungs of a chimpanzee from qingdao zoo, china. based on pathological findings, it is likely that the pinworms obtained access to these organs via the lymphatic or haematogenous pathway. as far as we are aware, this is the first reported case of enterobius sp. in the mesenteric lymph nodes and blood vessels of the lungs and veins ... | 1990 | 2338481 |
| c-terminal fragments of gp120 and synthetic peptides from five htlv-iii strains: prevalence of antibodies to the htlv-iii-mn isolate in infected individuals. | the immunoreactivity of htlv-iii-infected individuals and virus-inoculated chimpanzees with gp120 synthetic peptides of the htlv-iii gp120 envelope principle neutralizing domain (amino acid 301-324 sequences), derived from the htlv-iii isolates 3b, rf, mn, wmj2, and sc were determined. sequential bleeds from an infected lab worker and chimpanzees, both infected with the htlv-iiib, were immunoreactive only with the 3b peptide. in contrast, 33 htlv-iii-infected individuals were immunoreactive with ... | 1990 | 2340200 |
| organization of the chimpanzee c4-cyp21 region: implications for the evolution of human genes. | we prepared a cosmid library from chimpanzee dna and screened it with a mouse probe specific for the complement component 4 (c4)-encoding gene. we isolated 29 clones and constructed restriction maps for 20 of these. the clones could be arranged into two overlapping clusters covering the entire c4 region of both chromosomes in this particular heterozygous chimpanzee. the region is about 100 kilobases (kb) long and contains two c4 and two cyp21 genes, the latter coding for the enzyme 21-hydroxylas ... | 1990 | 2347361 |
| aspects of veterinary hemapheresis involving the horse, cow, sheep, goat, llama, dog and chimpanzee. | | 1990 | 2352998 |
| synaptic morphology of inner and outer hair cells of the human organ of corti. | innervations of inner and outer hair cells of the organ of corti of the human cochlea were studied by serial section electron microscopy. at the base of inner hair cells, presumed afferent fibers were of varying size and demonstrated synaptic specialization consisting of a presynaptic body, vesicles, and asymmetrical synaptic membrane specialization. two types of neurons, vesiculated presumably efferent and nonvesiculated presumably afferent, synapsed at the base of outer hair cells. the synapti ... | 1990 | 2355269 |
| ribosomal rna gene sequences and hominoid phylogeny. | sequences totaling 3,500 bases from the 28s rrna gene and from one of the ribosomal internal transcribed spacers (its1) have been determined for human, chimpanzee (pan troglodytes), gorilla (gorilla gorilla), and orangutan (pongo pygmaeus). analyses of the rrna alignments show (1) a clustering of substitutions in the "variable regions" of the 28s gene, (2) a 1.5-3-fold increase in divergence in the transcribed spacer over that in the exon, and (3) that human and chimpanzee are the most closely r ... | 1990 | 2359361 |
| protective efficacy of a novel hepatitis b vaccine consisting of m (pre-s2 + s) protein particles (a third generation vaccine). | the protective efficacy of a new type of yeast-derived hepatitis b (hb) vaccine (tgp-943, subtype adr), which was formulated from modified m (pre-s2 + s; p31) protein (m-p31c) particles, was investigated in chimpanzees. animals were injected intramuscularly three times at 4-week intervals with doses of 10 or 40 micrograms (as a protein) of tgp-943. there were no significant differences in the immunogenicity of 10 micrograms compared to that of 40 micrograms of tgp-943 in terms of anti-s antibody ... | 1990 | 2363298 |
| antibody-mediated in vitro neutralization of human immunodeficiency virus type 1 abolishes infectivity for chimpanzees. | this study was undertaken to establish whether antibody directed against the human immunodeficiency virus type 1 (hiv-1) principal gp120 type-specific neutralization determinant can abolish the infectivity of hiv-1 in chimpanzees. challenge inocula of the iiib virus isolate were mixed in vitro with either immunoglobulin g (igg) from an uninfected chimpanzee, nonneutralizing igg from an hiv-seropositive human, a virus-neutralizing murine monoclonal antibody directed against the hiv-1 iiib isolate ... | 1990 | 2370678 |
| emergence of viruses resistant to neutralization by v3-specific antibodies in experimental human immunodeficiency virus type 1 iiib infection of chimpanzees. | emergence in two chimpanzees of human immunodeficiency virus type 1 (hiv-1) iiib variants resistant to neutralization by the preexisting antibody is described. viruses isolated from the hiv-1 iiib gp120-vaccinated and -challenged animal were more resistant to neutralization by the chimpanzee's own serum than viruses isolated from the naive infected animal, indicating immune pressure as the selective mechanism. however, all reisolated viruses were 16- to 256-fold more neutralization resistant tha ... | 1990 | 2370681 |
| [the morphology of the palatine arch of pongids]. | with the help of frontal cuts through casts of skulls of pongids we demonstrated the postnatal development of the form of the hard palate. the form of the hard palate is similar to a semicircle in the frontal cut. in the chimpanzee the palatal form in the frontal cut ist not as semicircular as in the other great apes and is similar to the palatal form of humans in the molar region. the differences between pongo pygmaeus and the african apes consists in the fact, that the palate of the pongo pygm ... | 1990 | 2375499 |
| evolution of the glycophorin gene family in the hominoid primates. | analysis of nucleotide sequences of the human glycophorin a (gpa) and glycophorin b (gpb) genes has indicated that the gpa gene most closely resembles the ancestral gene, whereas the gpb gene likely arose from the gpa gene by homologous recombination. to study the evolution of the glycophorin gene family in the hominoid primates, restricted dna on southern blots from man, pygmy chimpanzee, common chimpanzee, gorilla, orangutan, and gibbon was probed with cdna fragments encoding the human gpa and ... | 1990 | 2383247 |
| isolation and characterization of a rat delta-aminolevulinate dehydratase processed pseudogene. | southern blot analysis of genomic dna from different strains of rat indicated that there were multiple copies of the gene encoding the second enzyme of the heme biosynthetic pathway, delta-aminolevulinate dehydratase (ala-d). two types of genomic clones were isolated from a sprague-dawley rat library. one appears to be the expressed gene, whereas the nucleotide sequence of the other suggests that it contains an ala-d processed pseudogene because (1) there are no introns, (2) there are multiple m ... | 1990 | 2387590 |
| further studies of 48-1 antigen in serial liver biopsies from chimpanzees infected with hepatitis delta virus. | the 48-1 antibody, initially reported to react specifically with non-a, non-b infected liver tissue, has been found to react also with liver specimens from chimpanzees infected with hepatitis delta virus (hdv). to clarify further the relation between hdv and appearance of the antigen reacting with the 48-1 antibody (48-1 ag), immunoperoxidase studies were carried out on serial liver specimens from chimpanzees infected with hdv. immunohistochemical and serological findings suggested that the appe ... | 1990 | 2388046 |
| heterogeneity of hepatitis delta antigen. | hepatitis delta antigen (hdag) is the only known protein encoded by the hepatitis delta virus (hdv). two hdag species of different sizes have been detected in the sera and livers of the infected humans, chimpanzees, and woodchucks, even though only one rna species was previously identified in most of the hdv strains. to study hdag heterogeneity, we took advantage of the fact that a single base mutation at nucleotide 1015 (c to u), which results in an amber termination codon in the hdag open read ... | 1990 | 2389557 |
| an epizootic of whooping cough among chimpanzees in a zoo. | | 1990 | 2394416 |
| the fibrinolytic potential of the normal primate following the generation of thrombin in vivo. | parameters of the fibrinolytic system were studied in a primate model where the generation of thrombin was promoted in vivo. the procoagulant stimulus used was a combination of human factor xa in combination with phosphatidylcholine/phosphatidylserine lipid vesicles (pcps) as the source of coagulant active phospholipid. the dosage of each component was formulated to provide a gradation of thrombin generating potential assessed prior to in vivo study in an in vitro clotting assay. these ranged fr ... | 1990 | 2402750 |
| the use of tri(n-butyl)phosphate detergent mixtures to inactivate hepatitis viruses and human immunodeficiency virus in plasma and plasma's subsequent fractionation. | the treatment of plasma with organic solvent/detergent mixtures at the time of plasma collection or pooling could reduce the exposure of technical staff to infectious viruses and enhance the viral safety of the final product. treatment of plasma for 4 hours with 2-percent tri(n-butyl)phosphate (tnbp) at 37 degrees c, with 1-percent tnbp and 1-percent polyoxyethylensorbitan monooleate (tween 80) at 30 degrees c, or with 1-percent tnbp and 1-percent polyoxyethylene ethers, (triton x-45) at 30 degr ... | 1990 | 2402772 |
| plasmodium falciparum: studies on mature exoerythrocytic forms in the liver of the chimpanzee, pan troglodytes. | mature exoerythrocytic forms (eef) of plasmodium falciparum from the chimpanzee were examined by light- and transmission electron microscopy from a liver biopsy taken on day 6 after sporozoite inoculation. infectivity of the sporozoites obtained from whole mosquitoes which were membrane fed on cultured gametocytes was about 4-6%. in comparison, salivary gland sporozoites added to human hepatocytes in vitro had only a developmental percentage of 0.02 to 0.05% at day 5. the eef found in the liver ... | 1990 | 2403931 |