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991.
Multipotent adult progenitor cells from bone marrow differentiate into functional hepatocyte-like cells 总被引:199,自引:0,他引:199
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Schwartz RE Reyes M Koodie L Jiang Y Blackstad M Lund T Lenvik T Johnson S Hu WS Verfaillie CM 《The Journal of clinical investigation》2002,109(10):1291-1302
We have derived from normal human, mouse, and rat postnatal bone marrow primitive, multipotent adult progenitor cells (MAPCs) that can differentiate into most mesodermal cells and neuroectodermal cells in vitro and into all embryonic lineages in vivo. Here, we show that MAPCs can also differentiate into hepatocyte-like cells in vitro. Human, mouse, and rat MAPCs, cultured on Matrigel with FGF-4 and HGF, differentiated into epithelioid cells that expressed hepatocyte nuclear factor-3beta (HNF-3beta), GATA4, cytokeratin 19 (CK19), transthyretin, and alpha-fetoprotein by day 7, and expressed CK18, HNF-4, and HNF-1alpha on days 14-28. Virtually all human, as well as a majority of rodent cells stained positive for albumin and CK18 on day 21; 5% (rodent) to 25% (human) cells were binucleated by day 21. These cells also acquired functional characteristics of hepatocytes: they secreted urea and albumin, had phenobarbital-inducible cytochrome p450, could take up LDL, and stored glycogen. MAPCs, which can be expanded in vitro and maintained in an undifferentiated state for more than 100 population doublings, can thus differentiate into cells with morphological, phenotypic, and functional characteristics of hepatocytes. MAPCs may therefore be an ideal cell for in vivo therapies for liver disorders or for use in bioartificial liver devices. 相似文献
992.
High-resolution 3D MRI of male pupae of Manduca sexta was performed at 2.35 T in order to evaluate its potential for an in vivo characterization of insect brain during metamorphosis. T1-weighted 3D FLASH (TR/TE = 20/7.8 ms, 25 degrees flip angle) and T2-weighted 3D fast SE MRI data sets (TR/TEeff = 3000/100 ms) were acquired at different developmental stages with an isotropic resolution of 100 microm. Both T1- and T2-weighted 3D MRI allowed for the identification of cerebral structures such as the antennal nerve, antennal and optical lobe, and central brain. Pronounced developmental alterations of the morphology were observed during metamorphosis. The results demonstrate the feasibility of 3D MRI at nanoliter resolution to identify major brain systems of M. sexta and respective changes during pupal development from caterpillar to sphinx moth. Together with the use of suitable contrast agents, this approach may provide new ways for studying the axonal connectivity and neural function of the developing insect brain. 相似文献
993.
The technique of dynamic imaging of the pharynx and some supplementary maneuvers which can be tailored to the individual patient's needs are discussed in detail. An approach to the analysis of normal and abnormal swallowing studies is presented. 相似文献
994.
PURPOSE: To assess the concurrent validity of the Human Activity Profile (HAP) with stroke and healthy control individuals, when reported by the subject or a proxy and compared to observed performance, used as gold standard; factors related to discrepancies; as well as to determine variables that could best predict physical activity levels. METHODS: A total of 24 stroke and 23 healthy control subjects took part in the study. Functional outcome measures included personal/demographic factors, HAP, the 10-meter walk, and cognition. RESULTS: Strong relationships were found between self-reported and observed scores for both groups (r=0.89-0.99). The relationships between proxy and observed scores were acceptable for stroke (r=0.80-0.87) but lower for control subjects (r=0.65-0.75), with intraclass correlation coefficients (ICCs) ranging from 0.69-0.89. Significant differences were found between proxy and observed scores for stroke, but not for control subjects. Discrepancies between scores showed little predictability from selected variables. For stroke subjects, the strongest variable explaining physical activity levels was walking speed (r2=43%) and the best combination of variables was walking speed plus cognition (r2=55%). CONCLUSIONS: Self-reported HAP was an excellent measure both for stroke and control subjects and related well to observed performance. Proxy reports appear to be valid for stroke subjects. HAP was significantly related to measures of walking speed. 相似文献
995.
996.
997.
Mnica de la Cueva‐Reguera David Rodríguez‐Sanz Csar Calvo‐Lobo Silvia Fernndez‐Martínez Beatriz Martínez‐Pascual Yolanda Robledo‐Do‐Nascimento María Blanco‐Morales Carlos Romero‐Morales 《International wound journal》2020,17(5):1453-1461
Perineal trauma (PT) may be considered as a very common injury during the childbirth. The incidence of PT was estimated in 30% to 85%, with 60% to 70% requiring suture. The present study was a prospective, single‐blinded, randomised, clinical trial carried out from January 2015 to January 2016. For this study, 49 secundigravida women diagnosed with gestational oedema were recruited and randomly divided into two groups (A and B). Group A (n = 30) received the conventional treatment plus perineal massage and group B (n = 19) the conventional treatment plus manual lymphatic drainage (MLD). Visual analogue scale (VAS) and King Health's Questionnaire (KHQ) were performed to assess pain intensity and quality of life‐related with urinary incontinence (UI). Pain intensity measurements showed statistically significant differences for a decrease after 30‐weeks (P = .037), after 36‐weeks (P = .000), and at the end of puerperium (P = .014) for MLD with respect to perineal massage group. Moreover, inter‐groups repeated measures ANOVA for the values related statistically significant differences to the interaction of each applied treatment (perineal massage and MLD group, separately) over the pain intensity variable. MLD treatment reduced pain intensity with respect to perineal massage in secundigravida women with gestational oedema from 25‐weeks of gestation to the end of puerperium. 相似文献
998.
999.
Kerstin Fischer Alimou Camara Ccile Troupin Sarah K. Fehling Thomas Strecker Martin H. Groschup Noel Tordo Sandra Diederich 《Transboundary and Emerging Diseases》2020,67(2):724-732
The genus Ebolavirus comprises several virus species with zoonotic potential and varying pathogenicity for humans. Ebolaviruses are considered to circulate in wildlife with occasional spillover events into the human population which then often leads to severe disease outbreaks. Several studies indicate a significant role of bats as reservoir hosts in the ebolavirus ecology. However, pigs from the Philippines have been found to be naturally infected with Reston virus (RESTV), an ebolavirus that is thought to only cause asymptomatic infections in humans. The recent report of ebolavirus‐specific antibodies in pigs from Sierra Leone further supports natural infection of pigs with ebolaviruses. However, susceptibility of pigs to highly pathogenic Ebola virus (EBOV) was only shown under experimental settings and evidence for natural infection of pigs with EBOV is currently lacking. Between October and December 2017, we collected 308 serum samples from pigs in Guinea, West Africa, and tested for the presence of ebolavirus‐specific antibodies with different serological assays. Besides reactivity to EBOV nucleoproteins in ELISA and Western blot for 19 (6.2%) and 13 (4.2%) samples, respectively, four sera recognized Sudan virus (SUDV) NP in Western blot. Furthermore, four samples specifically detected EBOV or SUDV glycoprotein (GP) in an indirect immunofluorescence assay under native conditions. Virus neutralization assay based on EBOV (Mayinga isolate) revealed five weakly neutralizing sera. The finding of (cross‐) reactive and weakly neutralizing antibodies suggests the exposure of pigs from Guinea to ebolaviruses or ebola‐like viruses with their pathogenicity as well as their zoonotic potential remaining unknown. Future studies should investigate whether pigs can act as an amplifying host for ebolaviruses and whether there is a risk for spillover events. 相似文献
1000.
Johanna Melke Feihu Zhao Keita Ito Sandra Hofmann 《Journal of orthopaedic research》2020,38(6):1228-1237
In bone tissue engineering (TE), an efficient seeding and homogenous distribution of cells is needed to avoid cell loss and damage as well as to facilitate tissue development. Dynamic seeding methods seem to be superior to the static ones because they tend to result in a more homogeneous cell distribution by using kinetic forces. However, most dynamic seeding techniques are elaborate or require special equipment and its influence on the final bone tissue-engineered construct is not clear. In this study, we applied a simple, dynamic seeding method using an orbital shaker to seed human bone marrow–derived mesenchymal stromal cells (hBMSCs) on silk fibroin scaffolds. Significantly higher cell numbers with a more homogenous cell distribution, increased osteogenic differentiation, and mineral deposition were observed using the dynamic approach both for 4 and 6 hours as compared to the static seeding method. The positive influence of dynamic seeding could be attributed to both cell density and distribution but also nutrient supply during seeding and shear stresses (0.0-3.0 mPa) as determined by computational simulations. The influence of relevant mechanical stimuli during seeding should be investigated in the future, especially regarding the importance of mechanical cues for bone TE applications. Our results highlight the importance of adequate choice of seeding method and its impact on developing tissue-engineered constructs. The application of this simple seeding technique is not only recommended for bone TE but can also be used for seeding similar porous scaffolds with hBMSCs in other TE fields. 相似文献