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1.
The geographic distribution of species is the typical metric for identifying priority areas for conservation. Since most biodiversity remains poorly studied, a subset of charismatic species, such as primates, often stand as surrogates for total biodiversity. A central question is therefore, how effectively do primates predict the pooled species richness of other mammalian taxa? We used lemurs as indicator species to predict total non-primate mammal community richness in the forest ecosystems of Madagascar. We combine environmental and species occurrence data to ascertain the extent to which primate diversity can predict (1) non-primate mammal α-diversity (species richness), (2) non-primate complementarity, and (3) non-primate β-diversity (species turnover). Our results indicate that primates are effective predictors of non-primate mammal community diversity in the forest ecosystems of Madagascar after controlling for habitat. When individual orders of mammals are considered, lemurs effectively predict the species richness of carnivorans and rodents (but not afrosoricids), complementarity of rodents (but not carnivorans or afrosoricids), and all individual components of β-diversity. We conclude that lemurs effectively predict total non-primate community richness. However, surrogate species alone cannot achieve complete representation of biodiversity.  相似文献   

2.
In many primate species, more ♂ ♂ than ♀ ♀ leave their natal group and transfer to another. In man, chimpanzee and the gorilla, however, the reverse is the case. This paper presents detailed data for the gorilla on individuals' movements into and out of breeding units. Comparisons are made with other primates, and with data on two non-primate species in which ♀♀ rather than ♂ ♂ move between breeding units. Proximate causes and functions of emigration and transfer are considered, and the reasons (proximate and evolutionary) for the observed sex differences in frequency of movement are discussed.  相似文献   

3.
Peterson FC  Brooks CL 《FEBS letters》2000,472(2-3):276-282
Primate growth hormones (GH) activate both primate and non-primate somatotrophic receptors (GH receptors), but non-primate GHs do not activate primate GH receptors. Previous studies argued the interaction of Asp(171) of human GH and Arg(43) of the receptor produced an attractive ionic interaction. In non-primate GHs, His(170) replaces the homologous Asp(171), producing a repulsive interaction with Arg(43) of the primate receptor which was believed to reduce the attraction of non-primate GH for the human GH receptor, thus providing species specificity. In this report, H170D bovine GH had activity and affinity for human GH receptors approaching those of human GH. In contrast, replacing Asp(171) of human GH with His did not significantly reduce somatotrophic activity, indicating that species specificity is not wholly explained by this residue's interaction with Arg(43) of the receptor. Deletion of either Phe(44) (a residue present only in primate GHs) or residues 32-46 (20-kDa form of human GH) each only marginally reduced somatotrophic activities. But the combination of the D171H mutation with either DeltaPhe(44) or Delta32-46 in human GH reduced binding and activity in a greater than additive fashion, indicated a functional interaction between these distant structural features. In bovine GH addition of phenylalanine at position 44 increased the somatotrophic activity and receptor affinity in cells containing the human GH receptor. The combination of the H170D mutation and the addition of phenylalanine at position 44 created a bovine GH with activity indistinguishable from wild-type human GH. Based on evidence from both bovine and human GHs, the cooperative interaction of these two distant motifs determined the species specificity and indicated that structural plasticity was a critical feature necessary for the species specificity of somatotrophic activity.  相似文献   

4.
The metabolic fate of amphetamine in man and other species   总被引:7,自引:7,他引:0  
1. The fate of [(14)C]amphetamine in man, rhesus monkey, greyhound, rat, rabbit, mouse and guinea pig has been studied. 2. In three men receiving orally 5mg each (about 0.07mg/kg), about 90% of the (14)C was excreted in the urine in 3-4 days. About 60-65% of the (14)C was excreted in 1 day, 30% as unchanged drug, 21% as total benzoic acid and 3% as 4-hydroxyamphetamine. 3. In two rhesus monkeys (dose 0.66mg/kg), the metabolites excreted in 24h were similar to those in man except that there was little 4-hydroxyamphetamine. 4. In greyhounds receiving 5mg/kg intraperitoneally the metabolites were similar in amount to those in man. 5. Rabbits receiving 10mg/kg orally differed from all other species. They excreted little unchanged amphetamine (4% of dose) and 4-hydroxyamphetamine (6%). They excreted in 24h mainly benzoic acid (total 25%), an acid-labile precursor of 1-phenylpropan-2-one (benzyl methyl ketone) (22%) and conjugated 1-phenylpropan-2-ol (benzylmethylcarbinol) (7%). 6. Rats receiving 10mg/kg orally also differed from other species. The main metabolite (60% of dose) was conjugated 4-hydroxyamphetamine. Minor metabolites were amphetamine (13%), N-acetylamphetamine (2%), norephedrine (0.3%) and 4-hydroxynorephedrine (0.3%). 7. The guinea pig receiving 5mg/kg excreted only benzoic acid and its conjugates (62%) and amphetamine (22%). 8. The mouse receiving 10mg/kg excreted amphetamine (33%), 4-hydroxyamphetamine (14%) and benzoic acid and its conjugates (31%). 9. Experiments on the precursor of 1-phenylpropan-2-one occurring in rabbit urine suggest that it might be the enol sulphate of the ketone. A very small amount of the ketone (1-3%) was also found in human and greyhound urine after acid hydrolysis.  相似文献   

5.
Comparative gene assignments of 18 markers, based on analyses of somatic cell hybrids and previous data in the literature, indicated that human (HSA) syntenic groups 3, 12, 14, and 15 are dissociated in the spider monkey species Ateles paniscus chamek (APC). Markers present in HSA 3p were allocated to APC 3 and APC 9. The HSA 12 cluster was split into two syntenic groups, one mainly including HSA 12p markers in APC 16 and the other, including HSA 12q markers, in APC 2p. The HSA 14q cluster split into three syntenic groups, corresponding to APC 2q, APC 6, and APC 12. Finally, the HSA 15 cluster split into two syntenic groups, APC 2q and APC 3. Comparisons with previous gene assignments and human SROs led to the tentative postulation of rearrangements having occurred during the evolutionary divergence of man and A. paniscus chamek. Chromosome painting data in the congeneric species A. geoffroyi, other New World and Old World primates, and several representative non-primate animals were compared in an attempt to delineate the ancestral and derived conditions underlying the evolutionary rearrangement of syntenic groups in mammals.  相似文献   

6.
The human gut harbors diverse bacterial species in the gut, which play an important role in the metabolism of food and host health. Recent studies have also revealed their role in altering the pharmacological properties and efficacy of oral drugs through promiscuous metabolism. However, the atomistic details of the enzyme-drug interactions of gut bacterial enzymes which can potentially carry out the metabolism of drug molecules are still scarce. A well-known example is the FDA drug amphetamine (a central nervous system stimulant), which has been predicted to undergo promiscuous metabolism by gut bacteria. Therefore, to understand the atomistic details and energy landscape of the gut microbial enzyme-mediated metabolism of this drug, molecular dynamics studies were performed. It was observed that amphetamine binds to tyramine oxidase from the Escherichia coli strain present in the human gut microbiota at the binding site harboring polar and nonpolar amino acids. The stability analysis of amphetamine at the binding site showed that the binding is stable and the free energy for the binding of amphetamine was found to be ~ −51.71 kJ/mol. The insights provided by this study on promiscuous metabolism of amphetamine by a gut enzyme will be very useful to improve the efficacy of the drug.  相似文献   

7.
E Ia T?tushkin 《Genetika》1983,19(3):353-361
The hypothesis suggesting that genetic distances between primate taxa are smaller than characteristic genetic distances between non-primate taxa having the similar level of phylogenetic affinity, due to the specific features of primate protein evolution, has been probed. To this end, genetic distances between green and rhesus monkeys representing different genera of one subfamily, and between humans and chimpanzees representing related families, have been calculated and compared. It has been shown that the former are 2-2,5 times smaller than the latter. It is pointed out in this connection that genetic distances reflect adequately the hierarchy of the above taxa, and the existing interpretation of the "paradox of genetic similarity" of man and apes needs to be corrected. To calculate genetic distances, we used both literature data and the results of comparative analysis of 9 electrophoretic gene markers of green and rhesus monkeys represented in this work. Differences in genetic variability of these species were detected.  相似文献   

8.
Desipramine is a widely used antidepressive agent that inhibits the reuptake of noradrenaline and serotonin, and central stimulants such as caffeine and amphetamine help to release noradrenaline and serotonin. This work aimed to evaluate whether the combination of these agents could produce a stronger antidepressant-like effect than either of the drugs alone. To this end, male mice were treated with different doses of desipramine, caffeine, amphetamine, desipramine-caffeine and desipramine-amphetamine. The results showed that all drugs produced decreased immobility time in the forced swimming model. The combined treatment of desipramine (0.31, 1.0 or 3.1 mg/kg i.p.) with caffeine or amphetamine (0.31 or 1 mg/kg i.p.) reduced immobility time greater than either of those drugs alone. The combined treatment of desipramine (0.31, 1 and 3.1 mg/kg i.p.) with amphetamine or caffeine (0.1 and 1 mg/kg i.p.) did not increase the motor activity significantly compared to the control. These results also suggested that drugs which promote the release of noradrenaline and serotonin could increase antidepressant-like effect of desipramine.  相似文献   

9.
(+)-Amphetamine and two structurally related analogues, 4-methoxyamphetamine and a recent "designer drug," 4-ethoxyamphetamine, were given to rats via subcutaneous osmotic minipumps for 1-14 days. Regional brain levels of the drugs as well as monoamine neurotransmitters and some of their major acidic metabolites were determined. Amphetamine produced depletions of dopamine in the striatum after at least 3 days of treatment but not in the nucleus accumbens of olfactory tubercle, even after 14 days of treatment. In contrast, the two ring-substituted amphetamine analogues increased levels of the monoamines and decreased levels of their acid metabolites. These data indicate that the two ring-substituted amphetamine analogues, at least one of which is a potent hallucinogen, have potent monoamine oxidase inhibition properties that are sustained during chronic treatment. Furthermore, these two compounds do not share amphetamine's regionally selective neurotoxic effects on dopamine-releasing terminals, even though brain and striatal drug levels are the same or higher than those of amphetamine.  相似文献   

10.
Interest in their animate environment was studied in a captive group of 11 stumptailed macaques (Macaca arctoides). Subjects were shown projected photographic slides, most of which showed a single individual primate or non-primate. The measure of interest was the duration of viewing. Results showed that adult females exhibited more interest towards stumptailed macaques versus other macaques species, and towards adult females carrying infants versus adult females alone. Data concerning non-primates showed that subjects were especially interested by photographs of felids; this effect was partly due to the presence of two frontal and conspicuous eyes in felids.  相似文献   

11.
Vectors based on lentiviruses efficiently deliver genes into many different types of primary neurons from a broad range of species including man and the resulting gene expression is long term. These vectors are opening up new approaches for the treatment of neurological diseases such as Parkinson's disease (PD), Huntington's disease (HD), and motor neuron diseases (MNDs). Numerous animal studies have now been undertaken with these vectors and correction of disease models has been obtained. Lentiviral vectors also provide a new strategy for in vivo modeling of human diseases; for example, the lentiviral-mediated overexpression of mutated human alpha-synuclein or huntingtin genes in basal ganglia induces neuronal pathology in animals resembling PD and HD in man. These vectors have been refined to a very high level and can be produced safely for the clinic. This review will describe the general features of lentiviral vectors with particular emphasis on vectors derived from the non-primate lentivirus, equine infectious anemia virus (EIAV). It will then describe some key examples of genetic correction and generation of genetic animal models of neurological diseases. The prospects for clinical application of lentiviral vectors for the treatment of PD and MNDs will also be outlined.  相似文献   

12.
The effects of the administration of serotonergic drugs on infusion rates of rats self-administering cocaine and amphetamine on an FR-10 schedule of reinforcement in daily 4 hour sessions were compared. Pretreatment with fluoxetine (2.5, 5, and 10 mg/kg), an inhibitor of serotonin reuptake, significantly decreased rates of responding maintained by amphetamine, but had no effect on responding maintained by cocaine at any of the doses tested. Pretreatment with cinanserin (3, 10, and 17.5 mg/kg), a serotonergic receptor antagonist, decreased rates of amphetamine self-administration at the highest dose tested, and also had no effect on cocaine self-administration. These data suggest a differential sensitivity of cocaine and amphetamine self-administration to pharmacological manipulation of central serotonin systems. They are consistent with biochemical data which demonstrates a negative correlation between the reinforcing potency of amphetamine-like drugs, but not cocaine-like drugs and their potency at serotonin binding sites.  相似文献   

13.
D K Pitts  J Marwah 《Life sciences》1988,42(9):949-968
Psychomotor stimulants (e.g. cocaine and amphetamine) and many antidepressants are believed to elicit their psychotropic actions by interacting primarily with central monoaminergic neurons. The acute central neuronal effects of amphetamine and antidepressants have been extensively investigated in rats utilizing extracellular single unit electrophysiological and microiontophoretic techniques in vivo. In recent years the chronic effects of these compounds on the above neuronal systems have also been reported. Such investigations have proliferated because of the realization that the mechanisms underlying the psychotomimetic effects (e.g. amphetamine and cocaine) and mood elevation (i.e. antidepressants) observed with the administration of these drugs are more accurately reflected in chronic studies. For many years it has been assumed that cocaine and amphetamine produce very similar if not identical psychotropic effects through their actions on central monoaminergic neurotransmission. In terms of effects on single monoaminergic neurons, this assumption had gone by untested until two years ago, when the first report of the electrophysiological effects of cocaine on central monoaminergic (locus ceruleus) neurons appeared in the literature (61). This review discusses recent electrophysiological studies with cocaine at the level of single identified monoaminergic neurons and compares such data with that previously reported for amphetamine and antidepressants. In addition to identifying some of the similarities and differences between these compounds, this review also highlights some of the gaps in our knowledge regarding the effects of these drugs on central monoaminergic neurotransmission.  相似文献   

14.
We present here a study of European Neogene primate occurrences in the context of changing humidity. We studied the differences of primate localities versus non-primate localities by using the mammal communities and the ecomorphological data of the taxa present in the communities. The distribution of primates is influenced by humidity changes during the whole Neogene, and the results suggest that the primates track the changes in humidity through time. The exception to this is the Superfamily Cercopithecoidea which shows a wider range of choices in habitats. All primate localities seem to differ from non-primate localities in that the mammal community structure is more closed habitat oriented, while in non-primate localities the community structure changes towards open-habitat oriented in the late Neogene. The differences in primate and non-primate localities are stronger during the times of deep environmental change, when primates are found in their preferred habitats and non-primate localities have faunas better able to adapt to changing conditions.  相似文献   

15.
D. Schmitt    S. G. Larson    J. T. Stern  Jr 《Journal of Zoology》1994,232(2):215-230
The serratus ventralis in mammals is a fan-shaped scapulo-thoracic muscle that is believed by most morphologists both to support body weight and to rotate the scapula during quadrupedal locomotion. Electromyographic studies of this muscle in cats, dogs and opossums confirm the dual supportive and rotatory roles of the serratus ventralis. Although this muscle has been studied in several primate species, the concentration on arboreal locomotion has resulted in an inadequate data set to permit direct comparisons to non-primate terrestrial quadrupeds. In order to provide a more comparable data set, we examined cranial, mid- and caudal thoracic regions of the serratus ventralis during terrestrial quadrupedalism in the vervet monkey, Cereopithecus aethiops. Our results indicate that the serratus ventralis does support the body during the stance phase of quadrupedalism in this primate. However, unlike several non-primate mammals, it plays a relatively insignificant rotatory role during swing phase.  相似文献   

16.
A sample of 117 fossil cercopithecids has been collected from the Middle Pleistocene site of Asbole, Afar Region, Ethiopia. A minimum of five species is present. There are two species of Cercopithecini, here recognized as cf. Chlorocebus aff. aethiops, and cf. Chlorocebus cf. patas. There are also two species of Papionini: Papio hamadryas ssp. indet. and Theropithecus oswaldi leakeyi. Finally, there is a single species of colobine present, Colobus sp. indet. The assemblage is chronologically constrained and is derived from sediments dated to approximately 600 ka. Within this sample Colobus sp. is by far the most common species present, outnumbering the other four species combined. The cercopithecid assemblage is most consistent with a woodland habitat, corroborating an earlier interpretation based on the non-primate fauna. Taxonomic, biogeographic, and evolutionary implications of the assemblage are also discussed.  相似文献   

17.
Previous research indicates that many primate species are more likely to give birth at night than during the day. This study attempted to determine whether temporal patterns of birth are discernible in a number of non-primate mammals. In addition, it sought to relate time of birth to the sleep/wake cycle and to the level of predation on the species. Data were collected and analyzed on birth hours in 26 mammalian species from two Chicago area zoos . Although temporal patterns of parturition were discernible for many species, the hypothesis that most birth would occur during the restive phase was not supported. However, a significant positive correlation between level of predation and the likelihood that birth would occur during the restive phase was found (n = 0.40). These findings are discussed in terms of predator/prey interaction and the protection (or lack of protection) that restive birthing might afford the mother and offspring at this vulnerable time.  相似文献   

18.
Parkinson disease (PD) is a chronic and progressive neurological disease associated with a loss of dopaminergic neurons. In most cases the disease is sporadic but genetically inherited cases also exist. One of the major pathological features of PD is the presence of aggregates that localize in neuronal cytoplasm as Lewy bodies, mainly composed of α-synuclein (α-syn) and ubiquitin. The selective degeneration of dopaminergic neurons suggests that dopamine itself may contribute to the neurodegenerative process in PD. Furthermore, mitochondrial dysfunction and oxidative stress constitute key pathogenic events of this disorder. Thus, in this review we give an actual perspective to classical pathways involving these two mechanisms of neurodegeneration, including the role of dopamine in sporadic and familial PD, as well as in the case of abuse of amphetamine-type drugs. Mutations in genes related to familial PD causing autosomal dominant or recessive forms may also have crucial effects on mitochondrial morphology, function, and oxidative stress. Environmental factors, such as MPTP and rotenone, have been reported to induce selective degeneration of the nigrostriatal pathways leading to α-syn-positive inclusions, possibly by inhibiting mitochondrial complex I of the respiratory chain and subsequently increasing oxidative stress. Recently, increased risk for PD was found in amphetamine users. Amphetamine drugs have effects similar to those of other environmental factors for PD, because long-term exposure to these drugs leads to dopamine depletion. Moreover, amphetamine neurotoxicity involves α-syn aggregation, mitochondrial dysfunction, and oxidative stress. Therefore, dopamine and related oxidative stress, as well as mitochondrial dysfunction, seem to be common links between PD and amphetamine neurotoxicity.  相似文献   

19.
In recent years, a number of newer designer drugs have entered the illicit drug market. The methylenedioxy-derivates of amphetamine represent the largest group of designer drugs. This paper describes a method for screening for and quantification of ten 2,5-methylenedioxy-derivates of amphetamine and phenylethylamine in human urine, using capillary electrophoresis coupled to electrospray ionisation-mass spectrometry (CE-ESI-MS). Prior to CE-MS analysis, a simple solid-phase extraction (SPE) was used for sample cleanup. The method was validates according to international guidelines.  相似文献   

20.
Ataxin-3 is a protein of unknown function which is mutated in Machado-Joseph disease by expansion of a genetically unstable CAG repeat encoding polyglutamine. By analysis of chicken ataxin-3 we were able to identify four conserved domains of the protein and detected widespread expression in chicken tissues. In the first such analysis in a non-primate species we found that in contrast to primates, the chicken CAG repeat is short and genetically stable.  相似文献   

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