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91.
Autoimmune diseases that are resistant to conventional treatment cause severe morbidity and even mortality. In the present study we demonstrate that complete remissions can be achieved in refractory polychondritis and systemic lupus erythematosus (SLE), even at advanced stage, with the use of autologous stem-cell transplantation (SCT). Remissions persisted after reconstitution of the immune system. In the treatment of advanced systemic sclerosis (SSc), stable disease may be achieved with autologous SCT.  相似文献   
92.
A rapid, sensitive and specific method was developed and validated using LC/MS/MS for determination of sorafenib in human plasma. Sample preparation involved a single protein precipitation step by the addition of 0.1 mL of plasma with 0.5 mL acetonitrile. Analysis of the compounds of interest including the internal standard ([(2)H(3)(15)N] sorafenib) was achieved on a Waters X-Terra C(18) (150 mm x 2.1mm i.d., 3.5 microm) analytical column using a mobile phase consisting of acetonitrile/10 mM ammonium acetate (65:35, v/v) containing 0.1% formic acid and isocratic flow at 0.2 mL/min for 6 min. The analytes were monitored by tandem mass spectrometry with electrospray positive ionization. Linear calibration curves were generated over the range of 7.3-7260 ng/mL for the human plasma samples with values for the coefficient of determination of >0.96. The values for both within day and between day precision and accuracy were well within the generally accepted criteria for analytical methods (<15%).  相似文献   
93.
We suggest a likelihood-based approach to estimate an overall rate of horizontal gene transfer (HGT) in a simplified setting. To this end, we assume that the number of occurring HGT events within a given time interval follows a Poisson process. To obtain estimates for the rate of HGT, we simulate the distribution of tree topologies for different numbers of HGT events on a clocklike species tree. Using these simulated distributions, we estimate an HGT rate for a collection of gene trees representing a set of taxa. As an illustrative example, we use the "Clusters of Orthologous Groups of proteins" (COGs). We also perform a correction of the estimated rate taking into account the inaccuracies due to gene tree reconstructions. The results suggest a corrected HGT rate of about 0.36 per gene and unit time, in other words 11 HGT events have occurred on average among the 44 taxa of the COG species tree. A software package to estimate an HGT rate is available online (http://www.cibiv.at/software/hgt/).  相似文献   
94.
95.
Autoimmune diseases that are resistant to conventional treatment cause severe morbidity and even mortality. In the present study we demonstrate that complete remissions can be achieved in refractory polychondritis and systemic lupus erythematosus (SLE), even at advanced stage, with the use of autologous stem-cell transplantation (SCT). Remissions persisted after reconstitution of the immune system. In the treatment of advanced systemic sclerosis (SSc), stable disease may be achieved with autologous SCT.  相似文献   
96.
Phosphoinositide-dependent kinase l (PDK1) phosphorylates and activates multiple AGC serine kinases, including protein kinase B (PKB), p70Ribosomal S6 kinase (S6K) and p90Ribosomal S6 kinase (RSK). PDK1 is required for thymocyte differentiation and proliferation, and herein, we explore the molecular basis for these essential functions of PDK1 in T lymphocyte development. A key finding is that PDK1 is required for the expression of key nutrient receptors in T cell progenitors: CD71 the transferrin receptor and CD98 a subunit of L-amino acid transporters. PDK1 is also essential for Notch-mediated trophic and proliferative responses in thymocytes. A PDK1 mutant PDK1 L155E, which supports activation of PKB but no other AGC kinases, can restore CD71 and CD98 expression in pre-T cells and restore thymocyte differentiation. However, PDK1 L155E is insufficient for thymocyte proliferation. The role of PDK1 in thymus development thus extends beyond its ability to regulate PKB. In addition, PDK1 phosphorylation of AGC kinases such as S6K and RSK is also necessary for thymocyte development.  相似文献   
97.
Due to concerns with biomass collection systems and soil sustainability there are opportunities to investigate the optimal plant fractions to collect for conversion. An ideal feedstock would require a low severity pretreatment to release a maximum amount of sugar during enzymatic hydrolysis. Corn stover fractions were separated manually and analyzed for glucan, xylan, acid soluble lignin, acid insoluble lignin, and ash composition. The stover fractions were also pretreated with either 0%, 0.4%, or 0.8% NaOH for 2 h at room temperature, washed, autoclaved and saccharified. In addition, dilute sulfuric acid pretreated samples underwent simultaneous saccharification and fermentation (SSF) to ethanol. In general, the two pretreatments produced similar trends with cobs, husks, and leaves responding best to the pretreatments, the tops of stalks responding slightly less, and the bottom of the stalks responding the least. For example, corn husks pretreated with 0.8% NaOH released over 90% (standard error of 3.8%) of the available glucan, while only 45% (standard error of 1.1%) of the glucan was produced from identically treated stalk bottoms. Estimates of the theoretical ethanol yield using acid pretreatment followed by SSF were 65% (standard error of 15.9%) for husks and 29% (standard error of 1.8%) for stalk bottoms. This suggests that integration of biomass collection systems to remove sustainable feedstocks could be integrated with the processes within a biorefinery to minimize overall ethanol production costs.  相似文献   
98.
The development of large tissue engineered bone remains a challenge in vitro, therefore the use of hybrid-implants might offer a bridge between tissue engineering and dense metal or ceramic implants. Especially the combination of the pseudoelastic implant material Nitinol (NiTi) with adipose derived stem cells (ASCs) opens new opportunities, as ASCs are able to differentiate osteogenically and therefore enhance osseointegration of implants. Due to limited knowledge about the effects of NiTi-structures manufactured by selective laser melting (SLM) on ASCs the study started with an evaluation of cytocompatibility followed by the investigation of the use of SLM-generated 3-dimensional NiTi-structures preseeded with ASCs as osteoimplant model. In this study we could demonstrate for the first time that osteogenic differentiation of ASCs can be induced by implant-mediated mechanical stimulation without support of osteogenic cell culture media. By use of an innovative implant design and synthesis via SLM-technique we achieved high rates of vital cells, proper osteogenic differentiation and mechanically loadable NiTi-scaffolds could be achieved.  相似文献   
99.
100.
The oncostatin M receptor (OSMR) is part of receptor complexes for oncostatin M and interleukin-31. Signaling events are triggered by Jaks (Janus kinases) that constitutively bind to membrane-proximal receptor regions. Besides their established role in signaling, Jaks are involved in the regulation of the surface expression of several cytokine receptors. Here, we analyzed the structural requirements within the human OSMR that underlie its limited surface expression in the absence of associated Jaks. We identified three dileucine-like motifs within the Jak-binding region of the OSMR that control receptor surface and overall expression. A receptor mutant in which all three motifs were mutated to alanine displayed markedly increased surface expression. Although the surface half-life of this mutant was increased compared with that of the wild-type receptor, no difference in the internalization rate was detectable, implying that these receptors differ in their post-endocytic fate. The protein stability of the wild-type receptor was markedly lower than that of mutant receptors, but could be strongly increased in the presence of the lysosomal inhibitor chloroquine. Our data are consistent with the dileucine motifs being involved in destabilization of receptors devoid of associated Jaks as part of a quality control ensuring signaling competence of OSMRs.  相似文献   
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