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Besides the liver, it has been difficult to identify which organ(s) and/or cellular component(s) contribute significantly to the production of human FVIII:c (FVIII). Thus far, only endothelial cells have been shown to constitute a robust extrahepatic source of FVIII, possibly explaining both the diverse presence of FVIII mRNA in the body, and the observed increase in FVIII levels during liver failure. Here, we investigate whether human mesenchymal stem cells (MSC), ubiquitously present in different organs, could also contribute to FVIII production. MSC isolated from human lung, liver, brain, and bone marrow expressed FVIII message as determined by quantitative‐RT‐PCR. Using an antibody specific for FVIII, confocal microscopy, and umbilical cord‐derived endothelial cells (HUVEC) as a negative control, we demonstrated that, in MSC, FVIII protein was not stored in granules; rather, it localized to the perinuclear region. Furthermore, functional FVIII was detected in MSC supernatants and cell lysates by aPTT and chromogenic assays. These results demonstrate that MSC can contribute at low levels to the functional FVIII pool, and advance the understanding of the physiology of FVIII production and secretion. J. Cell. Physiol. © 2012 Wiley Periodicals, Inc.  相似文献   
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Cell migration is the driving force behind the dynamics of many diverse biological processes. Even though microscopy experiments are routinely performed today by which populations of cells are visualized in space and time, valuable information contained in image data is often disregarded because statistical analyses are performed at the level of cell populations rather than at the single-cell level. Image-based systems biology is a modern approach that aims at quantitatively analyzing and modeling biological processes by developing novel strategies and tools for the interpretation of image data. In this study, we take first steps towards a fully automated characterization and parameter-free classification of cell track data that can be generally applied to tracked objects as obtained from image data. The requirements to achieve this aim include: (i) combination of different measures for single cell tracks, such as the confinement ratio and the asphericity of the track volume, and (ii) computation of these measures in a staggered fashion to retrieve local information from all possible combinations of track segments. We demonstrate for a population of synthetic cell tracks as well as for in vitro neutrophil tracks obtained from microscopy experiment that the information contained in the track data is fully exploited in this way and does not require any prior knowledge, which keeps the analysis unbiased and general. The identification of cells that show the same type of migration behavior within the population of all cells is achieved via agglomerative hierarchical clustering of cell tracks in the parameter space of the staggered measures. The recognition of characteristic patterns is highly desired to advance our knowledge about the dynamics of biological processes.  相似文献   
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Tissue engineering, an immensely important field in contemporary clinical practices, aims at the repair or replacement of damaged tissues. The mathematical model proposed herein shows the distribution and growth of cells in their characteristic time in a 3D scaffold model. This study contributes to the progress of simulation techniques in static and dynamic cultures of bone tissue. Brinkman, nutrient transport, and cell growth equations are brought together to quantify the growth behavior of cells. However, when a static culture is being studied, the Brinkman equation is eliminated. The model was validated by experimental cell culture using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay and scanning electron microscopy. Then, static and dynamic cultures were compared to assess the cell density and cell distribution in the scaffold. Cell counting after 21 days of cell culture showed that the number of cells increased 42‐fold in static and 53.5‐fold in dynamic cultures, which was in good agreement with our model estimations (37‐fold increase in the number of cells in static and 49‐fold increase in dynamic cultures). In conclusion, our mathematical model could predict cell distribution and growth in the scaffold.  相似文献   
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The kinematics of the human arm in terms of angles of rotations in the joints is reconstructed from the spatial tracking system (Fastrack() Polhemus) recordings. The human arm is modeled by three rigid bodies (the upper arm, the forearm and the hand) with seven degrees of freedom (three in the shoulder, two in the elbow and two in the wrist). Joint geometry parameters (orientations of the axes relative to the arm segments, the angles and the distances between the axes) have been calculated on the basis of passive rotations in the joints. The calculated parameters have been used to solve the direct kinematics problem for the reaching movements in different directions. The difference between calculated and recorded positions and accelerations of the hand has been used to assess the accuracy of the proposed method of kinematics reconstruction. The error analysis showed that spatial tracking system recordings and human arm kinematics reconstruction could reliably be used to accurately analyze multijoint movement in humans.  相似文献   
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Phenotypic and genetic parameter estimates for reproductive traits in Kermani sheep were estimated using reproductive records of 860 ewes. Data were collected during 1995–2007 at the experimental breeding station of Kermani sheep, south-east of Iran. Investigated traits were litter size at birth (LSB), litter size at weaning (LSW), litter mean weight per lamb born (LMWLB) and litter mean weight per lamb weaned (LMWLW) as basic traits, total litter weight at birth (TLWB) and total litter weight at weaning (TLWW) as composite traits. Quantitative genetic analyses were performed applying restricted maximum likelihood (REML) procedure under repeatability models. Ewe age had significant effect on LMWLB, LMWLW, TLWB and TLWW (P < 0.01). However, LSB and LSW were not affected by age of the ewe. All the studied traits were significantly affected by lambing year (P < 0.01). Direct heritability estimates for LSB, LSW, LMWLB, LMWLW, TLWB and TLWW were 0.01, 0.03, 0.13, 0.22, 0.06 and 0.18, respectively, while the corresponding repeatabilities were 0.08, 0.10, 0.17, 0.29, 0.09 and 0.23, respectively. Genetic correlation estimates between the investigated traits ranged from ?0.94 for LSB–LMWLB and LSW–LMWLW to 0.99 for LSB–TLWW. Phenotypic and environmental correlations were generally lower than those of genetic correlations. Phenotypic correlations ranged from ?0.34 for LSB–LMWLB to 0.58 for TLWB-TLWW. Environmental correlations ranged from ?0.33 for LSB–LMWLB and LSW–LMWLB to 0.33 for LMWLB–LMWLW. The results suggested that selection based on TLWW could be more effective than the other traits on improvement of reproductive performance in Kermani ewes.  相似文献   
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The aim of this study was to determine the prevalence and risk factors for subclinical endometritis (SE) and its effects on fertility in repeat breeder dairy cows. Dairy cows of parity 1 to 5 that were artificially inseminated (AI) 3 or more times (selected cows were artificially inseminated an average of 3.9 times) were examined at 190 ± 40 days in milk, and clinically normal cows (n = 77) were selected based on the absence of abnormal discharges on external inspection and the absence of abnormal findings on transrectal palpation and ultrasonographic examination. Endometrial samples were collected from the uterus by using the lavage technique in the luteal phase of the estrus cycle. Collected samples were centrifuged and a drop of sediment was streaked on to a clean microscopic slide and stained with Giemsa. The percentage of polymorphonuclear cells (neutrophils) was counted for each specimen. The analysed data showed that the average amount of neutrophils was 3.1% (0-9) in the selected cows. Abnormal calving (dystocia, twin births, and abortion), retained placenta, and postpartum uterine infections were associated with an increase in prevalence of SE. Subsequently, SE was significantly associated with a decrease in conception rate in the next AI. Conception rate in the next AI was 5% for cows (n = 38) with SE (≥ 3% neutrophil), and 47% for cows (n = 34) without SE (< 3% neutrophil) (P = 0.001). The prevalence of cytologically diagnosed SE (≥ 3% neutrophil) was 52.7% (n = 38). In conclusion, abnormal calving, retained placenta, and postpartum uterine infections may be associated with an increase in prevalence of SE and subsequently, SE may decrease reproductive performance and increase the incidence of repeat breeder syndrome.  相似文献   
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Bacterial DNA has been found in coronary plaques and it has therefore been concluded that bacteria may play a role as trigger factors in the chronic inflammatory process underlying coronary atherosclerosis. However, the microbial spectrum is complex and it is not known whether microorganisms other than bacteria are involved in coronary disease. Fungal 18S rDNA signatures were systematically investigated in atherosclerotic tissue obtained through catheter-based atherectomy of 38 patients and controls (unaffected coronary arteries) using clone libraries, denaturating gradient gel analysis (DGGE), in situ hybridization and fluorescence in situ hybridization (FISH). Fungal DNA was found in 35 of 38 (92.11%) coronary heart disease patients by either polymerase chain reaction (PCR) with universal primers or in situ hybridization analysis (n = 5), but not in any control sample. In a clone library with more than 350 sequenced clones from pooled patient DNA, an overall richness of 19 different fungal phylotypes could be observed. Fungal profiles of coronary heart disease patients obtained by DGGE analysis showed a median richness of fungal species of 5 (range from 2 to 9) with a high interindividual variability (mean similarity 18.83%). For the first time, the presence of fungal components in atherosclerotic plaques has been demonstrated. Coronary atheromatous plaques harbour diverse and variable fungal communities suggesting a polymicrobial contribution to the chronic inflammatory aetiology.  相似文献   
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Molecular Biology Reports - Clinical application of doxorubicin (DOX) is restricted due to its cardiotoxicity, reinforcing the significance of exploring new strategies to counteract DOX-induced...  相似文献   
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