Antibodies to simian T-lymphotropic retrovirus type III in African green monkeys and recognition of STLV-III viral proteins by AIDS and related sera.
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Porous ceramic (Al2O3) implants with pore size of 100--750 micron were placed intrabony in the maxilla and subperiosteally in the mandible of three adult monkeys. After observation periods of 10, 11 and 12 months, the animals were perfused with 1.7% glutaraldehyde and the jaws processed for electron microscopy. Tissue ingrowth into the pores was observed in all the specimens. The implant pores facing the host bone contained bone tissue to a depth of approximately 1 mm, while only unmineralized tissue was found in the implant part adjacent to the periosteum. The unmineralized tissue was of a fibrous nature with collagen fibers arranged in a lamellar fashion. Cells, often with extremely long and slender cellular processes, were seen between the lamellae. The cells had the cytoplasmic features typical of protein-producing cells. The mineralized tissue exhibited ordinary bone tissue structure with plate-like crystallites in a collagenous matrix. Some lacunae and canaliculi with osteocytes were observed, though they were scarce.
Forty vervet monkey half mandibles, 20 with unerupted third molars and 20 with erupted third molars, were partially embedded in acrylic and loaded in an Instron tensiometer. Mandibles with unerupted third molars fractured at 15.8 +/- 2.5 kg while those having erupted third molars fractured at 26.4 +/- 4.2 kg. Mandibles having unerupted third molars were shown to be significantly weaker than the mandibles with erupted third molar (t = 8.45, P less than 0.001).
Intraocular injections of tritiated proline were used to test the hypothesis that unilateral removal of all visual cortical areas results in increased distribution of retinal terminals in the pregeniculate nucleus (PGN) of the thalamus in monkeys. Following hemispherectomy, retinal input to the ipsilateral PGN was reduced by an average of 18.5% when compared to its contralateral homologue, which corresponded to the reduction in nuclear volume (19.3%). Our results show that removal of cortical afferents to the external layer of the PGN does not induce invasion of retinal projections into this region of the nucleus.
This study describes aspects of measles in non-human primates. Monkeys infected before importation are shown to produce non-immune offspring in captivity in England. The high antibody titres found in most recently imported monkeys decline slowly during captivity in England. While measles is often fatal to monkeys, we have described an outbreak in which a number of symptomless infections occurred. Histological examination of fatal cases produced evidence of infection in the wall of the urinary bladder in one monkey. The close similarity between measles in humans and monkeys has been confirmed. It is considered that the study of infection among the latter may have significance for the former.
Ternidens deminutus (Strongylida) is a parasitic nematode infecting non-human and human primates in parts of Africa, Asia and the Pacific islands. The present study genetically characterized T. deminutus and defined genetic markers in nuclear ribosomal DNA (rDNA) as a basis for developing molecular-diagnostic tools. The sequences of the second internal transcribed spacer (ITS-2) of rDNA were determined for adult specimens of T. deminutus (Nematoda: Strongylida: Oesophagostominae) from the Olive baboon and the Mona monkey. The length and G+C content of the ITS-2 sequences was 216 bp and approximately 43%, respectively. While there was no sequence variation among individual T. deminutus specimens from the baboon, 6 (2.8%) nucleotide differences were detected in the ITS-2 between the parasite from baboon and that of the Mona monkey, which is similar to the difference (3.2%) between 2 other species of Oesophagostominae (Oesophagostomum bifurcum and O. stephanostomum) from non-human primates, suggesting significant population variation or the existence of cryptic (i.e. hidden) species within T. deminutus . Pairwise comparisons of the ITS-2 sequences of the 2 operational taxonomic units of T. deminutus with previously published ITS-2 sequences for selected members of the subfamilies Oesophagostominae and Chabertiinae indicated that species from primates (including those representing the subgenera Conoweberia and Ihleia) are closely related, in accordance with previous morphological studies. The sequence differences (27-48.3%) in the ITS-2 between the 2 taxonomic units of T. deminutus and hookworms (superfamily Ancylostomatoidea) enabled their identification and delineation by polymerase chain reaction (PCR)-based mutation scanning. The genetic markers in the ITS-2 provide a foundation for improved, PCR-based diagnosis of T. deminutus infections and for investigating the life-cycle, transmission patterns and ecology of this parasite.
The nodule worm Oesophagostomum bifurcum (Nematoda: Strongylida) is a parasite of major human health importance predominantly in northern Togo and Ghana. Currently, it is estimated that 0.25 million people are infected with this nematode, and at least 1 million people are at risk of infection. Infection with this parasite causes significant disease as a consequence of encysted larvae in the wall of the large intestine. In spite of the health problems caused by O. bifurcum, there have been significant gaps in the knowledge of the biology, transmission and population genetics of the parasite. This review provides an account of some recent insights into the epidemiology and genetics of the parasite from human and non-human primate hosts in specific regions of Africa using molecular tools. Recent research findings are discussed mainly in relation to non-human primates being reservoirs of infection, and the consequences for the prevention and control of oesophagostomiasis in humans are briefly discussed.
The reverse transcriptase (RT) was partially purified by a newly developed procedure from the simian immunodeficiency virus TYO-7 isolated from an African green monkey (SIVagmTYO-7). The method comprised lysis of the virus with nonionic detergent followed by two centrifugations in isopycnic sucrose density gradients and one velocity sedimentation in a glycerol gradient. The enzyme exhibited a purity of 70-80% and showed an exceptional high specific activity of 135 nmol incorporation of dTMP per milligram of protein in 1 h with poly(rA).oligo(dT) as template-primer (TP). The molecular weight of the native enzyme was estimated by velocity sedimentation analysis as 120K-130K. Investigation of the RT by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) showed that the active enzyme is a heterodimer composed of a 64- and a 50-kDa subunit. The two subunits were identified to be RT specific by Western blot analysis. In activity gels, both subunits exhibited enzymatic activity, whereby the 64-kDa subunit showed the predominant activity. The RT preferred the TP poly(rA).oligo(dT) over poly(rC).oligo(dG). With poly(rCm).oligo(dG), only marginal activity was detected, and no activity was measured with poly(dA).oligo(dT). The TP specificity was influenced by the reaction temperature. The highest activity was measured around the melting temperature of the TP used. Furthermore, the enzyme activity was more thermolabile when measured with poly(rA).oligo(dT) than with poly(rC).oligo(dG). To compare the specificity of RT inhibitors, their inhibition efficiency (IE) was defined as the ratio of the 50% inhibiting concentration (ID50) obtained with the RT in viral lysates to the ID50 of purified RT.
A series of 6-aryl-1,2-dihydro-2,2,4-trimethylquinolines was synthesized and tested for functional activity on the human progesterone receptor isoform B (hPR-B) in mammalian (CV-1) cells. The lead compound LG001447 (1,2-dihydro-2,2, 4-trimethyl-6-phenylquinoline) was discovered via directed high throughput screening of a defined chemical library utilizing an hPR-B cotransfection assay. Electron-withdrawing substituents at the meta position of the C(6) aryl group afforded substantial improvements in hPR modulatory activity. Several analogues were able to potently block the effects of progesterone in vitro. Two compounds, 10 (LG120753) and 11 (LG120830) with potencies comparable or equal to the steroidal hPR antagonist onapristone (ZK98,299), were demonstrated to act as antiprogestins in vivo after oral administration to rodents. This is the first disclosure of orally active nonsteroidal antiprogestins.
The effect of lesions in a medullary pyramid was studied in two experiments. (a) Monkeys were trained to press a key with a rear-projected circle, presented together with different numbers of keys with ellipses. Two to eight choices were presented in a random sequence. Discrimination was measured with a titration schedule, and short choice reaction times were reinforced selectively. Choice reaction time and the function relating it to the number of choices were unaffected by lesions reducing the area of a transverse section of the pyramid up to 93%. (b) A repetitive response controlled by a fixed-ratio schedule was performed simultaneously with a holding response with the other hand, and the two hands changed function after each food pellet. Lesions reducing the pyramid only 25% increased interresponse times of the phasic response with the contralateral hand. Experiment 1 and previous studies are interpreted to indicate that slowing after pyramidal lesions is dependent on behavioral context. Experiment 2 showed that a simple repetitive movement is affected when the rate is high. The static response was more clearly affected than the phasic response, which indicates a role for the pyramidal tract in posture.
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Reciprocal altruism refers to the exchange of beneficial acts between individuals, in which the benefits to the recipient exceed the cost to the altruist. Theory predicts that cooperation among unrelated animals can occur whenever individuals encounter each other regularly and are capable of adjusting their cooperative behaviour according to experience. Although the potential for reciprocal altruism exists in many animal societies, most interactions occur between closely related individuals, and examples of reciprocity among non-kin are rare. The field experiments on vervet monkeys which we present here demonstrate that grooming between unrelated individuals increases the probability that they will subsequently attend to each others' solicitations for aid. Vervets appear to be more willing to aid unrelated individuals if those individuals have behaved affinitively toward them in the recent past. In contrast, recent grooming between close genetic relatives appears to have no effect on their willingness to respond to each other's solicitations for aid.
The characterization of HIV-1 (HTLV-III/LAV), the human retrovirus associated with AIDS (acquired immune deficiency syndrome) has led to the identification of a group of related human and simian retroviruses which also infect CD4-bearing T lymphocytes. Simian T-lymphotropic virus type III (simian immodeficiency virus) from macaques (STLV-IIIMAC) induces symptoms similar to those of AIDS in infected macaques, but isolates from African green monkeys (STLV-IIIAGM) and mangabeys (STLV-IIMM) appear to be non-pathogenic in these animals. A human virus immunologically related to STLV-IIIAGM (HTLV-IV), reported to have been isolated from healthy humans, has been shown to be almost identical to STLV-IIIAGM, which has called into question the independent origin of these viruses. Here we report the complete DNA sequence of STLV-IIIAGM and analyse its relationship with the genomes of the HTLV-IIIB strain of HIV-1, HIV-2ROD (previously called LAV-2) and several ungulate lentiretroviruses. STLV-IIIAGM and HIV-2 are closely related, and more distantly related to HIV-1.
New human retroviruses antigenically related to HIV and even more closely to STLV-III have been recently isolated from individuals from some West African countries. One of these viruses, HTLV-IVP, was reportedly isolated from lymphocytes of a healthy female prostitute. Another isolate, LAV-2FG, was obtained from an AIDS patient and third, SBL-6669, from an individual with lymphadenopathy. Current epidemiological studies indicate that some of these virus isolates cause immune deficiency whereas others may not or may be less efficient at inducing immune deficiency. Similarly, STLV-III apparently does not cause immune deficiency in its natural host, African green monkey. A novel feature of HIV is the possession of a gene termed tat, which is implicated in its pathobiology. We report here that, like HIV, HTLV-IVP, LAV-2FG (HIV-2) and SBL-6669, as well as STLV-IIIAGM possess the putative tat gene, irrespective of their pathogenic potential in vivo. Interestingly, HTLV-IVP/LAV-2FG long terminal repeat (LTR) is equally well transactivated by the HTLV-IVP/LAV-2FG and HTLV-IIIB tat function, HTLV-IIIB LTR responds better to its own tat function.
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