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1.
Oxytocin is widely believed to be present and structurally identical in all placental mammals. Here, we report that multiple species of New World monkeys possess a novel form of oxytocin, [P8] oxytocin. This mutation arises from a substitution of a leucine to a proline in amino acid position 8. Further analysis of this mutation in Saimiri sciureus (squirrel monkey) indicates that [P8] oxytocin is transcribed and translated properly. This mutation is specific to oxytocin, as the peptide sequence for arginine vasopressin, a structurally related nonapeptide, is unaltered. These findings dispel the notion that all placental mammals possess a 'universal' oxytocin sequence, and highlight the need for research on the functional significance of this novel nonapeptide in New World monkeys.  相似文献   

2.
A comparison of the distribution of brain monoamine neurons in several New World and Old World monkeys was undertaken using the Falck-Hillarp formaldehyde histofluorescence technique. The overall organization of the monoamine neurons was very similar in all species, although subtle variations were found. Catecholamine (noradrenaline and dopamine) and indoleamine (serotonin) cell bodies corresponding to groups A1–A7, A8–A10, and B1–B9, respectively were found throughout the brainstem. A few catecholamine (dopamine) cells equivalent to groups All and A12 in the diencephalon were also observed. Noradrenaline neurons, rather than those of the dopamine and serotonin systems, tended to be less numerous in the New World monkeys. Ascending catecholamine and indoleamine fiber bundles were observed in most monkeys. It is interesting that fibers corresponding to the “ventral noradrenaline bundle” appeared to be much finer in the common marmoset and tamarin than in other species. In addition, a substantial catecholamine (noradrenaline) innervation of the diencephalon was noted in all the Old World monkeys, while a much lower overall terminal density was apparent in the New World forms.  相似文献   

3.
Morphological features of the jaws and teeth are examined in eight species of platyrrhine monkeys that coexist in the Suriname rainforest. Z-scores calculated from geometric predictions for several features of the feeding apparatus thought to have some functional significance (e. g., tooth dimensions, jaw robusticity, leverage of primary jaw elevators) are compared to a profile of the naturalistic dietary behavior of these species (i. e., proportions of fruit mesocarp, seeds, leaves, and fauna eaten). Several features are found exclusively in those platyrrhines whose dietary preferences are the most limited. Such specializations appear to be associated with a particular protein source exploited by a species to supplement a largely frugivorous diet. Ateles paniscus, which feeds primarily on the mesocarp of ripe fruit, has an adaptive morphology that emphasizes broad incisors. Chiropotes satanas (and to a slightly lesser extent, Pithecia pithecia) is a frugivore/seed predator with large upper and lower canines and a robust mandible. The frugivore/folivore Alouatta seniculus has a relatively large total molar area and effective mandibular condyle height. In all four of these strictly vegetarian species, the leverage of the masseter muscle is greater than that of temporalis. Of the omnivorous species, Cebus apella and C. nigrivittatus exploit both fauna and seeds for protein and exhibit an array of many of the above features, such as large teeth and thick mandibles. Saimiri sciureus, not particularly known for seed predation, departs from Cebus in having less robust canines and a more gracile mandible. All three cebid omnivores have a temporalis with greater leverage than the masseter, indicating a requirement for resisting anteriorly directed forces, for example, using the jaws for vigorous foraging. The lack of any enlarged features, other than incisors, in the omnivorous Saguinus midas may be attributable to the functional constraints of small body size. Because the small size of the gape limits the size of the food parcel ingested, a requirement to enlarge other dentomandibular structures for trituration is alleviated.  相似文献   

4.
Blood infection by the simian parasite, Plasmodium simium, wasidentified in captive (n = 45, 4.4%) and in wild Alouatta clamitansmonkeys (n = 20, 35%) from the Atlantic Forest of southern Brazil. A single malariainfection was symptomatic and the monkey presented clinical and haematologicalalterations. A high frequency of Plasmodium vivax-specificantibodies was detected among these monkeys, with 87% of the monkeys testing positiveagainst P. vivax antigens. These findings highlight the possibilityof malaria as a zoonosis in the remaining Atlantic Forest and its impact on theepidemiology of the disease.  相似文献   

5.
A discriminant analysis was performed on 226 ceboid skulls using data on emissary foramina size and shape. The purposes of the study are to 1) measure the success with which these discriminating variables can distinguish among platyrrhine genera and 2) derive a set of classification functions which will permit the classification of new cases with unknown group membership (i.e., fossil skulls). This technique is able to correctly classify 80% of the 226 ceboid skulls. Support is given to the allocation of Chiropotes, Cacajao, and Pithecia into one morphologically unified subfamily, Pitheciinae. Alouatta, Ateles, and Lagothrix also share many similarities in emissary foramina size and shape and their inclusion into one subfamily, Atelinae, is probably warranted. The distinctiveness of Cebus in these same morphological features is apparent. Possibilities for extending this procedure to study fossil lineages in platyrrhines are discussed.  相似文献   

6.
The extraoral presence of taste signal transduction proteins has recently been reported in rodents and humans. Here, we report for the first time the presence of these signal transduction proteins in the caecum of a non-human primate, the common marmoset. Quantitative RT-PCR data on the gene expression of taste signal transduction molecules (gustducin and TRPM5) in common marmosets suggested high expression in the caecum, which was not observed in other non-human primates. Immunohistochemical analysis confirmed the specific presence of gustducin and taste receptors in marmoset caecal cells. These results may relate to the specific feeding behaviour of marmosets, which consume plant exudates, primarily gums.  相似文献   

7.
目的:探讨利用CT原始数据集对骨盆进行数字化三维分色构建的方法及意义。方法:选择1例因宫颈癌行盆腔CT薄层扫描患者的Dicom3.0原始二维断层数据集,利用Mimics10.01软件行骨盆三维分色重建。结果:构建的数字化三维分色模型形态规则、清晰逼真、立体感强、解剖清晰,不仅可以对构成骨盆的髂骨、骶骨及尾骨进行单独的三维分色显示,而且可以进行任意角度、距离的融合分离显示,更有利于对骨盆进行精细地全面立体观察分析。结论:基于CT薄层扫描数据集构建骨盆三维分色模型的方法简单、可行,是指导临床及教学的好工具。  相似文献   

8.
The high energetic costs of building and maintaining large brains are thought to constrain encephalization. The 'expensive-tissue hypothesis' (ETH) proposes that primates (especially humans) overcame this constraint through reduction of another metabolically expensive tissue, the gastrointestinal tract. Small guts characterize animals specializing on easily digestible diets. Thus, the hypothesis may be tested via the relationship between brain size and diet quality. Platyrrhine primates present an interesting test case, as they are more variably encephalized than other extant primate clades (excluding Hominoidea). We find a high degree of phylogenetic signal in the data for diet quality, endocranial volume and body size. Controlling for phylogenetic effects, we find no significant correlation between relative diet quality and relative endocranial volume. Thus, diet quality fails to account for differences in platyrrhine encephalization. One taxon, in particular, Brachyteles, violates predictions made by ETH in having a large brain and low-quality diet. Dietary reconstructions of stem platyrrhines further indicate that a relatively high-quality diet was probably in place prior to increases in encephalization. Therefore, it is unlikely that a shift in diet quality was a primary constraint release for encephalization in platyrrhines and, by extrapolation, humans.  相似文献   

9.
10.
目的应用CT技术对成年猕猴进行断层扫描,建立猕猴腹部及盆腔CT断层扫描图谱。方法选择普通级实验猕猴6只,雌雄各半,年龄5~8岁,取头前尾后仰卧位,采用增强扫描CT技术,对其腹部及盆腔进行断层扫描,采集容积数据及对原始数据重建。通过观察、确认,精选具有解剖意义的扫描图像:腹部7张、盆腔10张(雌雄各5张),对其每个层面的主要脏器进行标注。结果 CT影像能分辨出大部分组织器官的细微变化,较大器官、大血管界面清晰,但较小器官和细小血管、神经、肌肉组织等界面尚不清晰。结论获得了健康成年猕猴腹部及盆腔的影像学图谱,为CT技术在猕猴影像学研究、疾病的临床诊断及科学实验方面的应用,提供影像学的基础资料。  相似文献   

11.
Abstract: This report documents asymptomatic infections of Mycobacterium kansasii in four of five tuberculin positive squirrel monkeys (Saimiri sciureus sciureus). The mycobacterial DNA amplified by polymerase chain reaction (PCR) from a bronchial lymph node had no affinity for the species specific probes of M. tuberculosis, M. avium, and M. intracellular, thus allowing the presumptive diagnosis of an atypical mycobacterial infection. Infection by Mycobacterium kansasii was confirmed by culture of bronchial lymph nodes from three monkeys. The source of the infection was never identified.  相似文献   

12.
The purpose of this study was to compare the frontal sinus size of ancient Greenlandic Inuit with ancient Inuit of Alaska and Canada, and to compare sinus size between ancient and modern Greenlandic Inuit. Also, it was analyzed whether cranial size was a determinant of frontal sinus size. Frontal sinus size was evaluated in terms of absence frequency and planimetrically. Absence was defined as a frontal sinus not exceeding a line drawn between the supraorbital rims. A significant increase in absence frequency was noted from Alaska over Canada to Greenland (males: p<0.03; females p<0.0001). This is in accordance with earlier studies, indicating that although these Inuit populations once have been commonly related to the Old Bering Sea population, the Greenland Inuit represent an endpoint in an eastward migration. There was a significant increase (p<0.0001) in frontal sinus size from ancient to modern Greenlandic Inuit, probably indicative of a high degree of admixture with non-Inuit after modern colonization. The results regarding craniofacial size parameters and frontal sinus side were inconclusive. No single craniofacial variable showed significant effect on frontal sinus size, but the area displayed sexual dimorphism, females having smaller frontal sinuses.  相似文献   

13.
Concentrations of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in central (C) samples obtained by transfemorally catheterizing the inferior petrosal sinus of female bonnet monkeys were compared with those in peripheral (P) samples obtained simultaneously from the saphenous veins of two intact and two oophorectomized bonnet monkeys, before, during, and after luteinizing hormone releasing hormone (LHRH) stimulation. Significant differences between central and peripheral gonadotropin concentrations were detected intermittently in the resting state, and tended to be magnified by LHRH administration. In one animal in which LHRH was fortuitously administered during the course of a spontaneous LH surge, a C/P ratio for LH of 12.71, the maximum observed, was obtained. Spectral analysis exhibited periodicity for LH and, to a lesser extent, for FSH in the oophorectomized, but not in the intact, animals.  相似文献   

14.
15.
目的:探讨利用CTA原始数据集构建在体女性盆腔静脉血管网数字化三维模型的方法及意义。方法:基于双源CTA技术,获取1例宫颈癌患者的Dicom 3.0原始二维断层图像数据集。利用Mimics 10.01软件分别对骨盆、盆腔动脉血管网以及盆腔静脉血管网进行三维重建并配准融合。结果:构建的盆腔静脉血管网数字化三维模型可以清楚地显示下腔静脉、髂总静脉、髂外静脉、髂内静脉及其初级属支,以及双侧卵巢静脉等。与重建的骨盆、盆腔动脉血管网配准融合后,各支静脉血管的解剖走形及引流区域变得更加清晰明确。结论:基于CTA的计算机三维重建技术是一种研究女性盆腔静脉血管网的好方法,具有较大的运用价值。  相似文献   

16.
17.
The nine allopatric species of Aotus recognized represent two natural groups distinguished by karyotype, color, and pelage patterns. Correlated with these group characters are reported differences in serum proteins and degrees of susceptibility or immunity to experimental infection with malarial parasites. The primitive gray-neck species group of Aotus contains A. brumbacki (new species), A. lemurinus (with subspecies lemurinus and griseimembra), A. trivirgatus, and A. vociferans. The derived red-neck group contains A. nancymai (new species), A. miconax. A. infulatus, and A. azarae (with subspecies azarae and boliviensis). Only the two new species are described but a key to the species and subspecies gives the diagnostic characters of each. The gray-neck group occurs almost entirely north of the Amazon, the red-neck group almost entirely south. The distributional exceptions are enclave populations resulting from river bend cutoffs. Formation of an enclave population of A. nancymai is discussed and available information on the biology of this species is reported.  相似文献   

18.
Paradolichopithecus sushkini is a large fossil cercopithecine from the late Pliocene discovered at Kuruk-Say, southern Tajikistan. Despite its rather long face and large size, many authorities regard Paradolichopithecus not as a baboon, but as a large macaque, mainly based on the cranial morphology of European specimens. Among Old World monkeys, macaques are the only species that possess a maxillary sinus. Thus, we evaluated the presence/absence and morphology of this feature in P. sushkini using computed tomography (CT) scans of two Kuruk-Say cranial specimens in order to assess this species' taxonomic affinities. One of the specimens shows a thin bony wall separating a small area from the nasal cavity. Posterior to this structure is a pair of bony ridges: one protrudes from the alveolar process and the other descends from the superior portion of the nasal wall. A similar configuration was detected in the other specimen. These features strongly suggest the presence of a maxillary sinus in this species. This interpretation is supported by the fact that the superior portion of the alveolar process is excavated in the adult specimen. Thus, both specimens exhibit a maxillary sinus expanding laterally to share the external thin wall of the muzzle, and such a configuration may depend on the reduction of the maxillary bone, i.e., the presence of a maxillary fossa. The Kuruk-Say specimens probably retained a small maxillary sinus, despite the reduced size of the maxillary body. Thus, based on this evidence, P. sushkini probably belongs to the macaque lineage rather than that of baboons, although structural influences of the maxillary fossa leading to formation of the maxillary sinus have yet to be evaluated in extant macaques and baboons.  相似文献   

19.
A karyotypic study on a subspecies of the dusky titi,Callicebus moloch brunneus, was carried out and a third karyotype ofC. moloch was discovered. The chromosome number of this subspecies is 48. The autosomes consist of 5 subtelocentric, 5 submeta- or metacentric, and 13 acrocentric chromosome pairs. The X chromosome and the Y chromosome are submetacentric and metacentric, respectively. A comparative study with other subspecies of theC. moloch group (i.e.,C. m. cupreus andC. m. ornatus with 2n=46 andC. m. donacophilus with 2n=50) suggests that the karyotype ofbrunneus occupies a position intermediate between the two other karyotypes ofC. moloch, but nearer to that of 2n=50. The presumed total differences betweenbrunneus andcupreus comprise one Robertsonian rearrangement, one centromeric transposition and four pericentric inversions, and those betweenbrunneus anddonacophilus involve one translocation or breakage (possibly corresponding to two events, that is, one Robertsonian rearrangement and one centromeric transposition).  相似文献   

20.
The purpose of the present study is to characterize the ENaC-mediated Na+ absorption in human upper airway epithelia, nasal cavity, and paranasal sinus. To perform the purpose, we obtained epithelial cells from human nasal polyp (NP) and paranasal sinus mucosa (PSM) by endoscopic surgery. We measured the short-circuit current (I(sc)) sensitive to benzamil (a specific ENaC blocker). The benzamil-sensitive I(sc) (Na+ absorption) in NP was larger than that in PSM. The mRNA expression of three subunits of ENaC was as follows: alpha>beta>gamma in both tissue, NP and MS. The mRNA expression of gamma subunit of ENaC in NP was larger than that in PSM, but no difference of mRNA expression of alpha or beta ENaC subunit between NP and PSM was detected. We found correlation of the Na+ absorption to mRNA expression of gamma ENaC in NP and PSM. Forskolin diminished the Na+ absorption associated with an increase in Cl- secretion. These observations suggest that: (1) human NP absorbs more ENaC-mediated Na+ than PSM, (2) expression of gamma ENaC in plays a key role in the ENaC-mediated Na+ absorption in NP and PSM, and (3) cAMP diminishes the ENaC-mediated Na+ absorption by stimulating Cl- secretion (diminution of driving force for Na+ absorption) in NP and PSM.  相似文献   

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