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81.
We have fabricated a simple Si-MEMS device consisting of a microcantilever and a base to measure active tension generated by skeletal muscle myotubes derived from murine myoblast cell line C2C12. We have developed a fabrication process for integration of myotubes onto the device. To position myotubes over the gap between the cantilever and the base without damage due to mechanical peeling or the use of an enzymatic reaction, we cultured myotubes on poly-N-isopropylacrylamide (PNIPAAm) as a sacrifice layer. By means of immune staining of α-actinin, it was confirmed that a myotube micropatterned onto the device bridged the gap between the cantilever and the base. After 7d differentiation, the myotube was actuated by electrical stimulation. The active tension generated by the myotube was evaluated by measuring the bending of the cantilever using image processing. On twitch stimulation, the myotube on the device contracted and generated active tension in response to the electrical signals. On tetanus tension measurement, approximately 1.0 μN per single myotube was obtained. The device developed here can be used in wide area of in vitro skeletal muscle studies, such as drug screening, physiology, regenerative medicine, etc.  相似文献   
82.
Parasitology Research - Blastocystis sp. is a common intestinal protist found worldwide in a variety of animals, including humans. Currently, 17 subtypes (STs) of Blastocystis isolates from...  相似文献   
83.

Background

Malposition of tibial components is an important factor for complications in unicompartmental knee arthroplasty (UKA), but the direct relationship between clinical outcomes and position of tibial component remains unknown. We aimed to investigate whether tibial component rotation in the axial plane could affect clinical outcomes after UKA.

Methods

A total of 50 patients with anteromedial osteoarthritis of the knee underwent Oxford mobile-bearing UKA in this study. Patient-derived clinical scores using the Oxford Knee Score (OKS) and the functional activities of Knee Society Score (KSSF) were assessed preoperatively, and then after one year and two years following surgery. Postoperative tibial component rotation angles using two reference lines in the axial plane were assessed using three-dimensional computed tomography two weeks postoperatively. External rotation of the tibial component relative to each reference line was considered a positive value. We analysed the sequential change of the OKS and KSSF using repeated measures analysis of variance (P?<?0.05). The effects of tibial component rotation on the OKS and KSSF were analysed using linear regression analysis.

Results

OKS and KSSF showed significant recovery between the preoperative and one-year postoperative period. Rotation angles of tibial components had significant negative correlations with the recovery of the OKS in the two years following UKA.

Conclusions

Tibial component rotation played an important role in improving clinical outcomes during the two years following Oxford mobile-bearing UKA. A trend towards poor outcome was observed when the tibial component was placed at a higher angle of external rotation.Level of evidence: III.  相似文献   
84.
Objective:  Curdlan, an extracellular bacterial polysaccharide, is a linear β-1,3-glucan. Previously, we developed Curdlan-oligo (CRDO). We investigated its effect on the production of cytokines in leukocytes from mice, and compared its activity with that of SCG, a 6-branched 1,3-β-glucan. Methods:  Splenocytes from DBA/2 mice were cultured with CRDO or SCG (0, 1, 10 or 100 μg/ml) in vitro, and then the supernatants were collected to measure cytokines. Bone marrow-derived dendritic cells (BMDCs) were cultured with CRDO (0, 1, 10 or 100 ng/ml) in vitro, and then the supernatant was collected to measure cytokines. Results:  SCG stimulated splenocytes in DBA/2 mice to produce GM-CSF, IFN-γ and TNF-α. CRDO induced production of GM-CSF and IFN-γ, but not TNF-α. The amounts of GM-CSF and IFN-γ were small compared with those produced in response to SCG. The effect of SCG on TNF-α production was partially inhibited by CRDO. In bone marrow-derived dendritic cells, CRDO induced production of TNF-α and IL-6. Conclusion:  Taken together, these results suggest that CRDO stimulated mouse leukocytes to induce the production of cytokines, and the mechanism of the effect of CRDO on leukocytes is different from that of SCG. Received 30 June 2008; returned for revision 5 August 2008; received from final revision 3 September 2008; accepted by A. Bauhofer 22 September 2008  相似文献   
85.
We present a case of short-rib polydactyly syndrome (SRPs) type 3 in which accurate prenatal diagnosis was feasible using both ultrasonography and 3D-CT. SRP encompass a heterogeneous group of lethal skeletal dysplasias. However, the phenotypes overlap with those of nonlethal skeletal dysplasias (i.e. Ellis-van Creveld syndrome and Jeune syndrome). As accurate prenatal diagnosis of SRP is helpful for parents, we used 3D-CT in the early third trimester to examine a fetus suggested to have phenotypes of 'short-rib dysplasia group' on ultrasonography. 3D-CT showed mild modification of the vertebral bodies, small ilia with horizontal acetabula and triangular partial ossification defects, and subtle metaphyseal irregularities of the femora. These CT findings and an extensive literature search regarding the phenotypes of various diseases categorized as short-rib dysplasia group led to a correct prenatal diagnosis of SRP type 3. This case exemplified the usefulness of 3D-CT for the precise prenatal diagnosis of skeletal dysplasias.  相似文献   
86.

Purpose  

Uterine leiomyomas are the most common benign tumors of reproductive age women, but there is no effective medical therapy to data. Aim of this study was to examine and compare the efficacy of gonadotropin-releasing hormone agonist (GnRHa) versus dienogest in premenopausal women with uterine myoma.  相似文献   
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89.
It has been described that tumor progression has many similarities to inflammation and wound healing in terms of the signaling processes involved. Among biological responses, angiogenesis, which is necessary for tumor progression and metastasis, is a common hallmark; therefore, tumor blood vessels have been considered as important therapeutic targets in anticancer therapy. We focused on pentraxin 3 (PTX3), which is a marker of cancer‐related inflammation, but we found no reports on its expression and function in tumor blood vessels. Here we showed that PTX3 is expressed in mouse and human tumor blood vessels based on immunohistochemical analysis. We found that PTX3 is upregulated in primary mouse and human tumor endothelial cells compared to normal endothelial cells. We also showed that PTX3 plays an important role in the proliferation of the tumor endothelial cells. These results suggest that PTX3 is an important target for antiangiogenic therapy.  相似文献   
90.
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