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281.
282.
Caterina Motta Eduardo Palermo Valeria Studer Marco Germanotta Giorgio Germani Diego Centonze Paolo Cappa Silvia Rossi Stefano Rossi 《PloS one》2016,11(2)
Background
The available clinical outcome measures of disability in multiple sclerosis are not adequately responsive or sensitive.Objective
To investigate the feasibility of inertial sensor-based gait analysis in multiple sclerosis.Methods
A cross-sectional study of 80 multiple sclerosis patients and 50 healthy controls was performed. Lower-limb kinematics was evaluated by using a commercially available magnetic inertial measurement unit system. Mean and standard deviation of range of motion (mROM, sROM) for each joint of lower limbs were calculated in one minute walking test. A motor performance index (E) defined as the sum of sROMs was proposed.Results
We established two novel observer-independent measures of disability. Hip mROM was extremely sensitive in measuring lower limb motor impairment, being correlated with muscle strength and also altered in patients without clinically detectable disability. On the other hand, E index discriminated patients according to disability, being altered only in patients with moderate and severe disability, regardless of walking speed. It was strongly correlated with fatigue and patient-perceived health status.Conclusions
Inertial sensor-based gait analysis is feasible and can detect clinical and subclinical disability in multiple sclerosis. 相似文献283.
Human embryonic stem cells (hESCs) are a promising source for cell therapy in degenerative diseases. A key step in establishing the medical potential of hESCs is the development of techniques for the conversion of hESCs into tissue-restricted precursors suitable for transplantation. We recently described the derivation of multipotent mesenchymal precursors from hESCs. Nevertheless, our previous study was limited by the requirement for mouse feeders and the lack of in vivo data. Here we report a stroma-free induction system for deriving mesenchymal precursors. Selective culture conditions and fluorescence-activated cell sorting (FACS)-mediated purification yielded multipotent mesenchymal precursors and skeletal myoblasts. Skeletal muscle cells undergo in vitro maturation resulting in myotube formation and spontaneous twitching. We found that hESC-derived skeletal myoblasts were viable after transplantation into the tibialis anterior muscle of SCID/Beige mice, as assessed by bioluminescence imaging. Lack of teratoma formation and evidence of long-term myoblast engraftment suggests considerable potential for future therapeutic applications. 相似文献
284.
Nicolae C Ko YP Miosge N Niehoff A Studer D Enggist L Hunziker EB Paulsson M Wagener R Aszodi A 《The Journal of biological chemistry》2007,282(30):22163-22175
Matrilins are oligomeric extracellular matrix adaptor proteins mediating interactions between collagen fibrils and other matrix constituents. All four matrilins are expressed in cartilage and mutations in the human gene encoding matrilin-3 (MATN3) are associated with different forms of chondrodysplasia. Surprisingly, however, Matn3-null as well as Matn1- and Matn2-null mice do not show an overt skeletal phenotype, suggesting a dominant negative pathomechanism for the human disorders and redundancy/compensation among the family members in the knock-out situation. Here, we show that mice lacking both matrilin-1 and matrilin-3 develop an apparently normal skeleton, but exhibit biochemical and ultrastructural abnormalities of the knee joint cartilage. At the protein level, an altered SDS-PAGE band pattern and a clear up-regulation of the homotrimeric form of matrilin-4 were evident in newborn Matn1/Matn3 and Matn1 knock-out mice, but not in Matn3-null mice. The ultrastructure of the cartilage matrix after conventional chemical fixation was grossly normal; however, electron microscopy of high pressure frozen and freeze-substituted samples, revealed two consistent observations: 1) moderately increased collagen fibril diameters throughout the epiphysis and the growth plate in both single and double mutants; and 2) increased collagen volume density in Matn1(-/-)/Matn3(-/-) and Matn3(-/-) mice. Taken together, our results demonstrate that matrilin-1 and matrilin-3 modulate collagen fibrillogenesis in cartilage and provide evidence that biochemical compensation might exist between matrilins. 相似文献
285.
286.
Todd Vannelli Alex Studer Michael Kertesz Thomas Leisinger 《Applied microbiology》1998,64(5):1933-1936
Methylobacterium sp. strain CM4 metabolized chloromethane quantitatively with a molar yield of 2.8 g of whole-cell protein/mol of C. This value was similar to that observed after growth with methanol (2.9 g of protein/mol of C) and about three times larger than the yield with formate (0.94 g of protein/mol of C). Chloromethane dehalogenation activity was inducible. MiniTn5 transposon insertion mutants with altered growth characteristics with chloromethane and other C1 compounds were isolated and characterized. Nine of these were unable to grow with chloromethane but were able to grow with methanol, methylamine, or formate. Seventy-three transposon mutants that were defective in the utilization of either methanol, methylamine, methanol plus methylamine, or formate could still grow with chloromethane. Based on the protein yield data and the properties of the transposon mutants, we propose a pathway for chloromethane metabolism that depends on methyltransferase and dehydrogenase activities. 相似文献
287.
Sequence of drought response of maize seedlings in drying soil 总被引:2,自引:0,他引:2
Urs Schmidhalter Michel Evéquoz KarlHeinz Camp Christoph Studer 《Physiologia plantarum》1998,104(2):159-168
Leaf elongation in monocotyledonous plants is sensitive to drought. To better understand the sequence of events in plants subjected to soil drying, leaf elongation and transpiration of maize seedlings ( Zea mays L.) of 4 cultivars were monitored continuously and the diurnal courses of the root and leaf water relations were determined. Results from this study indicate the following sequence of drought response: Leaf elongation decreased before changes in the leaf water relations of non‐growing zones of leaf blades were detected and before transpiration decreased. Reductions in leaf elongation preceded changes in the root water potential (ψw ). Root ψw was not a very sensitive indicator of soil dryness, whereas the root osmotic potential (ψs ) and root turgor (ψp ) were more sensitive indicators. The earliest events observed in drying soil were a significant increase in the largest root diameter class (1 720 to 1 960 gm) and a decrease in leaf elongation ( P = 0.08) 2 days after withholding water. Significant increases in root length were observed 2 days later. Soil drying increased the number of fine roots with diameters of <240 µm. Slight increases in soil strength did not affect leaf elongation in the drying soil. 相似文献
288.
A. terreus isolates isolated from some bakery products, corn and rice were found to be able to produce territrems. 90% of theA. terreus isolated from bakery products were able to produce territrem A, with a mean of 0.09 ppm, while 80% ofA. terreus isolates produce territrem B with a mean of 0.24 ppm. On the other hand 31.8% of the isolates ofA. terreus from corn were able to produce territrem A with a mean of 0.44 ppm. ConcerningA. terreus isolates from rice, 66.7% were found to produce territrem A, with a mean of 5.28 ppm, and 77.8% of the isolates produced
territrem B with a mean of 1.79 ppm. 相似文献
289.
290.
Modelling the epidemiological impact of intermittent preventive treatment against malaria in infants
Ross A Penny M Maire N Studer A Carneiro I Schellenberg D Greenwood B Tanner M Smith T 《PloS one》2008,3(7):e2661