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PubMed1977

Transmission of hepatitis B to chimpanzees by hepatitis B surface antigen-positive saliva and semen.

To assess the infectivity of hepatitis B surface antigen (HBsAg)-containing body fluids other than blood, chimpanzees were inoculated intravenously with saliva and semen obtained from HBsAg-positive individuals implicated in non-percutaneous transmission of hepatitis B. Saliva and semen samples were negative for occult blood. The titer of HBsAg in saliva was on the average only 1/3,000 that of the corresponding serum. One chimpanzee, inoculated sequentially with saliva from three individuals, developed HBsAg at 9 weeks and serum glutamic pyruvic transaminase elevation at 13 weeks after injection. HBsAg persisted for 15 weeks. This animal also developed e antigen, anti-core antibody, and anti-surface antibody. Liver biopsies showed acute hepatitis that subsequently resolved. A second chimpanzee, inoculated with HBsAg-positive semen, developed HBsAg and elevated serum glutamic pyruvic transaminase 4 weeks after inoculation and then died suddenly without explanation. HBsAg was positive in two consecutive samples and was confirmed by specific neutralization. Autopsy did not reveal evidence of hepatitis. This study demonstrates that HBsAg-positive saliva and, probably, semen contain infectious virus and suggests that saliva and/or semen may serve as important mechanisms in the transmission of type B hepatitis.

Animals↗
PubMed1977

The recent rise to the alpha-rank in a population of free-living chimpanzees.

The recent rise of a high-ranking adult male chimpanzee to the alpha male position of the Gombe National Park's Kasakela chimpanzee community is reported. The male Figan is the fourth individual to assume this status in the wild chimpanzees' social hierarchy during Goodall's 16 year study in Tanzania. The paper describes the overthrow of the previous top-ranking male, and the manner in which Figan has maintained his new position after the take-over. Emphasis is placed upon his relationship with his elder male sibling, Faben, and the second highest-ranking male in the community, Evered.

Aggression↗
PubMed1976

Technique of laparoscopy in the chimpanzee.

We have developed the technique of laparoscopy in the chimpanzee using a modification of the standard human procedure. The technique requires careful management, but permits repeated examination, high quality photography, ovarian biopsy, follicle aspiration and injections into the ovary. The chimpanzee may thus be useful for evaluating new techniques or instrumentation intended for human patients. In addition, laparoscopy access to the internal genitalia enhances the value of the chimpanzee as an experimental model.

Abdomen↗
PubMed1976

Development and chimpanzee testing of a vaccine against human hepatitis B.

Highly purified hepatitis B virus surface antigen (Australia antigen) purified by physical and chemical procedures from infected human plasma was used to prepare hepatitis B vaccine. The purified antigen was treated with formalin and the vaccine was tested exhaustively for safety by ordinary procedures and additionally in marmosets (for live hepatitis B virus). The vaccine was highly potent, inducing antibody in guinea pigs, grivet monkeys, and chimpanzees given three doses of vaccine containing up to 20 mug of hepatitis B antigen per dose. A protective efficacy trial was carried out in chimpanzees that were given three doses of vaccine subcutaneously and then challenged intravenously with 1000 chimpanzee infectious doses of human hepatitis B virus. All of five unvaccinated control animals developed hepatitis B virus antigenemia following challenge and all of six vaccinated animals were protected, including one animal that had failed to develop detectable antibody following vaccination.

Animals↗
PubMedDate not supplied

The metabolism of (2-cyclopentyl-6,7-dichloro-2-methyl-1-oxo-5-indanyloxy)acetic acid in chimpanzee and man.

The metabolism of the polyvalent saluretic agent (2-cyclopentyl-6,7-dichloro-2-methyl-1-oxo-5-indanyloxy)acetic acid was studied in chimpanzee and man. The drug was well absorbed and extensively metabolized by man. Peak levels of drug (5--8 microgram/ml) occurred within 1.5--4.5 hr of drug administration. The plasma half-life was estimated to be 2 hr; a similar half-life was observed in the chimpanzee. Little unchanged drug (less than 10%) was excreted in the urine of either species. Similar metabolic profiles were obtained for man and chimpanzee. The major urinary metabolites resulted from hydroxylation of the cyclopentyl moiety, giving rise to a number of diastereomers. The alcohol metabolites were subsequently oxidized to the ketone. The excretion of the metabolites coincided with maximal excretion of sodium and chloride ions. The hydroxylated metabolites have intrinsic pharmacological activity.

Animals↗
PubMed1977

Chimpanzee livers after infection with human hepatitis viruses A and B: Ultrastructural studies.

Electron microscopical studies were carried out on coded liver biopsy specimens from chimpanzees inoculated with human hepatitis A or B virus. Hepatitis B was recognized by the presence of hepatitis B core particles in hepatocellular nuclei. Hepatitis A was characterized by unidentified large, dense, and more irregular heterochromatin-like particles in hepatocellular nuclei coincidental with peak aminotransferase activities. As type A hepatitis illness became manifest in the chimpanzees, mitochondrial cristae were curled and attenuated, and clusters of endoplasmic reticulum were tightly packed. In contrast, the livers in viral hepatitis B showed mainly hypertrophy of tubular smooth endoplasmic reticulum. This suggested different pathogenetic mechanisms in A and B chimpanzee viral hepatitis.

Animals↗
PubMed1975

Conversations with a chimpanzee in a computer-controlled environment.

The linguistic-type skills of a young chimpanzee (Pan) acquired in a computer-controlled language-training situation are reviewed. Those skills include facile acquisition of vocabulary, object naming, color naming, appropriate use of "yes" and "no" in response to certain questions, and conversation. In conversations the subject has formulated novel sentences and without special training has asked that objects be named, whereupon requests were made that they be given to her. These findings are interpreted in terms of how enriched environments can serve to bring forth novel communication skills in the chimpanzee, which is otherwise alinguistic; how the challenge of the environment can serve to limit manifest intelligence; and how a cognitive, rather than the traditional stimulus-response, framework is required for understanding the communication skills and psychological processes of the chimpanzee.

Animals↗
PubMed1976

Immunity in infection with Neisseria gonorrhoeae: duration and serological response in the chimpanzee.

Relative and absolute resistance to urethral and pharyngeal infection with Neisseria gonorrhoeae persisted for up to two years in male chimpanzees parenterally immunized with a colony type 2 gonococcal antigen. Twelve additional adult males were immunized with either a colony type 1 gonococcal antigen or a sham diluent before being challenged with the immunizing isolate of N. gonorrhoeae. Serum specimens were obtained throughout the immunization procedure and tested for indirect fluorescent, bactericidal, microhemagglutinating, and complement-fixing antibody to the immunizing isolate of N. gonorrhoeae. The serological response measured by the indirect fluorescent antibody and serum bactericidal tests correlated most closely with the resistance of individual chimpanzees when they were challenged in the pharynx and urethra with graduated doses of N. gonorrhoeae one month after the last immunization. In this study, the resistance of the immunized chimpanzees to urethral infection with N. gonorrhoeae varied from one to greater than 1,000 times that of sham-injected controls.

Animals↗
PubMed1976

The pathology of viral hepatitis types A and B in chimpanzees. A comparison.

The histologic manifestations in the livers of chimpanzees inoculated with hepatitis A and B virus were compared with each other and correlated with biochemical, serologic, and virologic observations. Both types of hepatitis reveal alterations similar to those seen in human hepatitis, but the lesions--particularly the hepatocellular necrosis--are far milder. Hepatitis Type A in chimpanzees is a disease of short incubation period and duration. The hepatocytic alterations are mainly restricted to the periportal areas, and the parenchymal changes are less severe than the portal inflammation. The lesions correlated well with biochemical changes, the presence of virus in the liver, and its shedding in the stool. In contrast, experimental Type B hepatitis has a long incubation period and longer duration, involves the entire lobular parenchyma, and is, if anything, more severe in the lobular centers while portal inflammation is less conspicuous. Biochemical alterations and presence of virus in the liver correlate with these lesions, and the antibody response is similar to that seen in man. The chimpanzee is a useful model for studying the pathogenesis of viral hepatitis; additional study of serial morphologic events may contribute to our understanding of the clinical differences between hepatitis Type A and Type B.

Animals↗
PubMed2026

STRONGYLID COINFECTIONS IN SYMPATRIC CHIMPANZEES AND GORILLAS FROM THE REPUBLIC OF THE CONGO REVEALED BY FECAL METAGENOMICS.

Soil-transmitted strongylid nematodes are common intestinal parasites of African great apes, yet most surveys have relied on microscopy or targeted PCR assays that are limited in taxonomic breadth and comparability across hosts. I reanalyzed 46 publicly available shotgun fecal metagenomes from sympatric central chimpanzees (Pan troglodytes troglodytes; n = 18) and western lowland gorillas (Gorilla gorilla gorilla; n = 28) in the Goualougo Triangle, Nouabalé-Ndoki National Park, Republic of the Congo, to test whether host species structures genus-level strongylid community composition and relative read signal. Non-host reads were classified against a custom strongylid-focused database targeting 4 genera repeatedly reported from African apes: Ancylostoma, Necator, Oesophagostomum, and Trichostrongylus. All 4 focal genera were detected in every library under baseline filtering, and multi-genus detection remained robust under increasingly stringent read-count thresholds. However, host species differed strongly in community composition. Chimpanzee libraries had relatively even genus-level profiles, whereas gorilla libraries were consistently Necator-dominated. Gorillas also had substantially higher relative strongylid read abundance. The results show that shotgun metagenomic reanalysis can recover host-structured strongylid community signals from wildlife samples and can complement targeted parasitological surveys in conservation and One Health surveillance.

Animals↗
PubMed1979

Reproductive function in aged female chimpanzees.

Reproductive function was evaluated in ten female chimpanzees (Pan troglodytes) aged 35-48 years. Forty-eight years is the longevity record for the chimpanzee. Data on cycle frequency and duration was available for seven animals. Most were cycling regularly until death, and all had experienced at least one menstrual cycle within one year of death. After exclusion of periods when the animals were pregnant or in postpartum amenorrhea, the mean cycle frequency (+/- standard error)/year was 9.54 +/- 0.20 in seven animals aged 15-25 (432 cycles analyzed) compared to 8.6 +/- 0.76 in the same animals at age 35 + years (405 cycles analyzed); this effect approached significance (p = 0.072, Mann-Whitney U-test). Cycle length of 16 cycles in each of seven animals aged 15-25 was 32.23 +/- 0.38 days. The same animals when aged over 35 had mean cycle lengths of 35.59 +/- 0.73. This difference was not significant, although cycle lengths clearly increased with age in some individual animals. In five aged animals for which mating data was available, appropriate exposure to a male occurred in 52 cycles, but only two pregnancies occurred; one pregnancy resulted in a live birth at age 38, the other in a stillbirth at age 40. This conception rate was 3.85% compared with 20% in the same animals aged 15-25. These data suggest greatly reduced fertility after age 35, although menstrual cycle frequency remained high. The persistence of menstrual cyclicity until death, which occurred due to natural causes at latest in the fifth decade, is in striking contrast to the human female in which menopause occurs in the fifth decade and death is often postponed for several more decades.

Aging↗
PubMed1978

[About the comparison of closely related species chimpanzee-man and fox-dog in respect of the possibility of xenotransplantation (author's transl)].

Although the transplant combinations chimpanzee-man on one hand and fox-dog on the other hand have nearly the same phylogenetic development within their zoological family, it is not quite correct to compare the immunological reactions and patterns of rejection of xenogeneic transplants within these systems. The differences in immunochemistry of serum proteins between these two systems confirm that chimpanzee and man are more closely related than fox and dog concerning their genetic disparity. This and other mentioned examples demonstrate the possibility of obtaining qualitative informations of genetic constellations between xenogeneic species combinations by comparing immunochemistry of serum proteins.

Animals↗
PubMed1975

Metabolism of 4-14 C-progesterone in the adult female chimpanzee.

The metabolism of 4- 14-C-progesterone was studied in two adult female chimpanzees (Pan troglodytes). After intravenous injection of 4- 14-C-progesterone, urine was collected for 5 days. The urinary conjugates were hydrolyzed with Glusulase and the extracts purified by chromatography on silica gel, paper and alumina and then crystallized to constant specific activity with or without carrier steroid. The major metabolite in both experiments was pregnanediol which accounted for 39.8% and 49.5% of the recovered dose respectively. Pregnanolone (0.6% and 2.1%) and pregnanetriol (0.1% and 1.5%) were also isolated in smaller quantities. These data suggest that the pattern of progesterone metabolism in the chimpanzee is similar to that of man in that pregnanediol is the major metabolite whereas androsterone is not.

Aluminum↗
PubMed1977

Correlation of serum testosterone levels with age in male chimpanzees.

Serum testosterone was measured in a group of male chimpanzees of varying ages by radioimmunoassay using a specific antiserum to testosterone-3-carboxym ethyloxime-bovine serum albumin. The juvenile age group, ranging from one through six years (n=26), had a mean serum testosterone value of 13ng/100ml (range 3.5-59ng/100ml). The adolescent age group, spanning years seven through ten (n=19), had a mean value of 178ng/100ml (range 14.6-238ng/100ml). The adult group, comprised of animals over eleven years of age (n=29), had a mean peripheral serum testosterone value of 397ng/100ml (range 92-680ng/100ml). These data suggest that serum testosterone levels may be useful in determing the age and sexual maturity of chimpanzees of unknown age.

Aging↗
PubMedDate not supplied

Concentrations of circulating steroids in normal prepubertal and adult male and female humans, chimpanzees, rhesus monkeys, rats, mice, and hamsters: a literature survey.

Radioimmunoassay (RIA) data on concentrations of circulating steroids in normal prepubertal and adult male and female humans, chimpanzees, rhesus monkeys, rats, mice, and hamsters have been collated from the literature. Few reports include data for both sexes, for age groups, or for more than one species. In selecting references for inclusion in the tables, efforts were made to choose data only from RIA procedures that were adequately validated. A number of similarities can be found by reviewing the tables. Levels of estradiol appear somewhat similar for humans, chimpanzees, and rhesus monkeys of both sexes. Among the notable differences are the levels of estradiol and progesterone in primates and rodents, the apparently high level of aldosterone in mice, and the patterns of progesterone secretion in mice and rats. All values in the tables have been converted to picograms for easy comparison between steroids and species. Data for humans are fairly complete, but there is a significant lack of information for several other species.

Adult↗
PubMed1976

Hepatitis A antigen particles in liver, bile, and stool of chimpanzees.

Virus-like hepatitis A antigen (HA Ag) particles, presumably hepatitis A virus, were isolated from the liver, bile, and stool of three chimpanzees that had been infected with stool filtrates containing HA Ag particles. Specimens of serum, stool, liver biopsy material, and bile were obtained at selected intervals during the experiment. The animals developed mild hepatitis 19-21 days after inoculation, and antibody to HA Ag appeared de novo in their convalescent-phase serum. During acute illness, virus-like particles similar to the HA Ag particle were seen in liver cell cytoplasm by electron microscopy. HA Ag particles were detected by immune electron microscopy and a new radioimmunoassay in isopycnically banded samples of liver, bile, and stool. HA Ag particles were found at densities of 1.29-1.39 g/cm3, but the major peak density for antigen particles in samples of liver, bile, and stool was approximately 1.34 g/cm3. The fact that HA Ag particles can be recovered from chimpanzee liver, bile, and stool makes these potentially important sources of infectious and antigenic materials.

Animals↗
PubMed1978

Human foamy virus: further characterization, seroepidemiology, and relationship to chimpanzee foamy viruses.

A foamy virus present in human nasopharyngeal carcinoma tissue was studied for a number of biological properties, including range of cellular susceptibility, growth curve, evolution of cytopathic effect in relation to cellular fusion and intracellular viral distribution, reverse transcriptase activity, and buoyant density. The virus was also studied immunologically and found to be closely related to the chimpanzee foamy viruses, particularly simian foamy virus type 6, with which it shares common antigens in complement-fixing, fluorescent, and neutralizing antibody tests. In view of this close immunological relationship and the failure to find antibody to the human isolate in sera from more than 250 humans, including 50 patients with nasopharyngeal carcinoma and Burkitt's lymphoma, it is suggested that the isolate is not a human representative of the foamy virus group but rather a variant strain of chimpanzee foamy virus.

Animals↗