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51.
Ordean J. Oyen Robert W. Rice Donald H. Enlow 《American journal of physical anthropology》1981,54(3):415-419
An analysis of skulls from several primate species shows that a “worm-track” surface pattern, first identified in the brow region in fossil adult hominids and subsequently in olive baboons, chimpanzees, and macaques, is also present in numerous other species. Fine cancellous bone and its attendant vermiculate surface pattern have been observed in subadult and adult gelada baboons, gibbons, gorillas, and orangutans as well as in modern Homo sapiens and several Plio-Pleistocene fossil hominids. In contemporary primates, fine cancellous bone has been identified not only in the brow region, but also along the zygomatic arch, on the pterygoid plates, on the maxilla, along the temporal line, on the mastoid process, and in the region of inion. Given the widespread distribution of this trait, caution is advised when using it as a diagnostic indicator of the evolutionary or functional significance of craniofacial morphology. 相似文献
52.
ATPase activity and phosphorylation by [γ-32P] ATP of isolated plasma membrane of alveolar macorphages are stimulated in a parallel fashion by physiologic concentrations of Ca2+, with half-maximal activating effect of this ion at (3–7) × 10?7 M. For various membrane preparations, a direct proportionality exists between Ca2+-dependent ATPase activity and amount of 32P incorporated. Labeling of membrane attains the steady-state level by 10 sec at 0°C, and is rapidly reversed by adenosine diphosphate (ADP). K+ decreases the amount of membrane-bound 32P, mainly by enhancing the rate of dephosphorylation of the 32P-intermediate. Hydroxylamine causes a release of about 90% of 32P bound to the membrane, thus indicating that the 32P-intermediate contains an acyl-phosphate bond. When the labeled plasma membrane is solubilized and electrophoresed on acrylamide gels in the presence of sodium dodecyl sulphate, the radioactivity appears to be largely associated with a single protein fraction of 132,500 ± 2,000 apparent molecular weight. These features of the macrophage Ca2+-ATPase suggest that the enzyme activity might be part of a surface-localized Ca2+-extrusion system, participating in the regulation of Ca2+-dependent activities of the macrophage. 相似文献
53.
Frances P. Schulter 《American journal of physical anthropology》1976,44(3):453-468
A comparative study was made to determine race and sex differences in the temporal bone, to investigate growth relationships, and to establish a basis for phylogenetic studies of the temporal bone and the temporal lobe of the brain. Data on Eskimo, Indian, and white crania were collected from radiographs and directly from the skulls. Of the 25 variables studied, only the minimum diameter of porus failed to demonstrate some difference among the races. Variation between sexes was found for all measurements except the cranial base angle (of deflection) and three angles related to the petrous pyramids. Correlation coefficients indicated that none of the angles are related in any consistent manner to the other variables studied. This is interpreted as further evidence of cranial base stability. The Indians have the lowest, longest squamae, differing most from the whites. The position of squama is more anterior in the Eskimos. Females of each race possess more anteriorly positioned squamae than males. When the squama is more anteriorly located, the porus is in a more posterior position within the squama itself. Strong race variation exists in the shape of porus. In order to establish a basis for phylogenetic studies of the temporal lobe of the brain better reference points for reflecting its size and shape must be found. 相似文献
54.
Colin C Demasi MA Degaki TL Bustos-Valenzuela JC Figueira RC Montor WR Cruz LO Lojudice FH Muras AG Pereira TM Winnischofer SM Hasegawa AP Carreira AC Verbisck NV Corrêa RG Garay-Malpartida HM Mares-Guia TR Corrêa-Giannella ML Granjeiro JM Sogayar MC 《Molecular biotechnology》2008,39(2):89-95
Social and economical development is closely associated with technological innovation and a well-developed biotechnological industry. In the last few years, Brazil’s scientific production has been steadily increasing; however, the number of patents is lagging behind, with technological and translational research requiring governmental incentive and reinforcement. The Cell and Molecular Therapy Center (NUCEL) was created to develop activities in the translational research field, addressing concrete problems found in biomedical and veterinary areas and actively searching for solutions by employing a genetic engineering approach to generate cell lines over-expressing recombinant proteins to be transferred to local biotech companies, aiming at furthering the development of a national competence for local production of biopharmaceuticals of widespread use and of life-saving importance. To this end, mammalian cell engineering technologies were used to generate cell lines over-expressing several different recombinant proteins of biomedical and biotechnological interest, namely, recombinant human Amylin/IAPP for diabetes treatment, human FVIII and FIX clotting factors for hemophilia, human and bovine FSH for fertility and reproduction, and human bone repair proteins (BMPs). Expression of some of these proteins is also being sought with the baculovirus/insect cell system (BEVS) which, in many cases, is able to deliver high-yield production of recombinant proteins with biological activity comparable to that of mammalian systems, but in a much more cost-effective manner. Transfer of some of these recombinant products to local Biotech companies has been pursued by taking advantage of the São Paulo State Foundation (FAPESP) and Federal Government (FINEP, CNPq) incentives for joint Research Development and Innovation partnership projects. 相似文献
55.
Bronchioalveolar morphogenesis of human bronchial epithelial cells depending upon hepatocyte growth factor
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Takashi Kato Kiyomasa Oka Toshikazu Nakamura Akihiko Ito 《Journal of cellular and molecular medicine》2015,19(12):2818-2826
Lung alveolar regeneration occurs in adult human lungs as a result of proliferation, differentiation and alveolar morphogenesis of stem cells. It is increasingly being believed that bronchial epithelial cells (BECs) have a potential as stem cells, because they are potent to differentiate into multiple central and peripheral lung cell types in three‐dimensional (3D) cultures, and they develop multiple foci with well‐differentiated histogenesis after transformed into neoplastic cells. In this study, we investigated morphogenic abilities of HBE135 human BECs immortalized by E6/E7 oncogene in 3D cultures. When HBE135 cells were cultured alone or co‐cultured with endothelial cells, the cells formed spherical colonies without branching. However, in co‐culture with lung fibroblast MRC‐9 cells, HBE135 cells formed colonies with bronchioalveolar‐like complex branching, suggesting that MRC‐9‐derived soluble factor(s) are responsible for the branching formation. MRC‐9 cells, not endothelial cells, were found to highly express hepatocyte growth factor (HGF), a soluble molecule involved in liver and kidney regeneration. An anti‐HGF neutralizing antibody severely suppressed the complex branching formation, but addition of HGF could not sufficiently compensate the morphogenic effects of MRC‐9 cells, suggesting that MCR‐9‐derived HGF was necessary but insufficient for the bronchioalveolar structure formation. Immunohistochemistry revealed that Met, a cognate receptor for HGF, was highly expressed and phosphorylated in neoplastic BECs from lung adenocarcinomas with well‐differentiated, not poorly differentiated, histogenesis. These results are consistent with the notion that BECs have an aspect of stem cells. This aspect appears to become manifest through HGF–Met signalling pathway activation. 相似文献
56.
Edward Málaga-Trillo Evgenia Salta Antonio FiguerasCynthia Panagiotidis Theodoros Sklaviadis 《生物化学与生物物理学报:疾病的分子基础》2011,1812(3):402-414
Transmissible spongiform encephalopathies (TSEs), otherwise known as prion disorders, are fatal diseases causing neurodegeneration in a wide range of mammalian hosts, including humans. The causative agents - prions - are thought to be composed of a rogue isoform of the endogenous prion protein (PrP). Beyond these and other basic concepts, fundamental questions in prion biology remain unanswered, such as the physiological function of PrP, the molecular mechanisms underlying prion pathogenesis, and the origin of prions. To date, the occurrence of TSEs in lower vertebrates like fish and birds has received only limited attention, despite the fact that these animals possess bona fide PrPs. Recent findings, however, have brought fish before the footlights of prion research. Fish models are beginning to provide useful insights into the roles of PrP in health and disease, as well as the potential risk of prion transmission between fish and mammals. Although still in its infancy, the use of fish models in TSE research could significantly improve our basic understanding of prion diseases, and also help anticipate risks to public health. This article is part of a Special Issue entitled Zebrafish Models of Neurological Diseases. 相似文献
57.
Jabbarzadeh E Jiang T Deng M Nair LS Khan YM Laurencin CT 《Biotechnology and bioengineering》2007,98(5):1094-1102
Bone tissue engineering offers promising alternatives to repair and restore tissues. Our laboratory has employed poly(lactide-co-glycolide) PLAGA microspheres to develop a three dimensional (3-D) porous bioresorbable scaffold with a biomimetic pore structure. Osseous healing and integration with the surrounding tissue depends in part on new blood vessel formation within the porous structure. Since endothelial cells play a key role in angiogenesis (formation of new blood vessels from pre-existing vasculature), the purpose of this study was to better understand human endothelial cell attachment, viability, growth, and phenotypic expression on sintered PLAGA microsphere scaffold. Scanning electron microscopy (SEM) examination showed cells attaching to the surface of microspheres and bridging the pores between the microspheres. Cell proliferation studies indicated that cell number increased during early stages and reached a plateau between days 10 and 14. Immunofluorescent staining for actin showed that cells were proliferating three dimensionally through the scaffolds while staining for PECAM-1 (platelet endothelial cell adhesion molecule) displayed typical localization at cell-cell contacts. Gene expression analysis showed that endothelial cells grown on PLAGA scaffolds maintained their normal characteristic phenotype. The cell proliferation and phenotypic expression were independent of scaffold pore architecture. These results demonstrate that PLAGA sintered microsphere scaffolds can support the growth and biological functions of human endothelial cells. The insights from this study should aid future studies aimed at enhancing angiogenesis in three dimensional tissue engineered scaffolds. 相似文献
58.
Bone marrow stromal cells produce nerve growth factor and glial cell line-derived neurotrophic factors 总被引:19,自引:0,他引:19
García R Aguiar J Alberti E de la Cuétara K Pavón N 《Biochemical and biophysical research communications》2004,316(3):753-754
Bone marrow stromal cells (BMSC) have attracted interest through their possible use for cell therapy in neurological diseases. Recent reports demonstrated that these cells are able to migrate and have potential for neuronal differentiation after transplantation into brain parenchyma. The objective of this work was determine whether rat BMSC express NGF and GDNF, in order to study its potential application for treatment of neurodegenerative diseases. BMSC were harvested from male rats and cultured in DMEM supplemented with 20% fetal bovine serum. At passage 6 the total RNA was isolated using TriZol reactive. RT-PCRs to evaluate the expression of NGF and GDNF using specific primers were carried out. Our results indicate that rat BMSC have potential to produce NGF and GDNF. We have not found any report in favor of GDNF or NGF production from rat BMSC. 相似文献
59.
为了长期培养骨髓基质细胞和研究其对病毒的敏感性,我们采用静置贴壁培养法,体外长期培养了胎儿、儿童和成人骨髓基质细胞,并将传至5代以上的肌样骨髓基质细胞采用微量细胞病变(CPE)法,开展了对5种病毒的敏感性试验。结果表明,人骨髓基质肌样细胞对滤泡性口腔炎病毒,脊髓灰质炎病毒、Ⅰ型和Ⅱ型单纯疱疹病毒均敏感,能产生明显的CPE,其效价(TCID50)可达10^-3~10^-4,其中胎儿骨髓基质肌样细胞对 相似文献
60.