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61.
62.
[Purpose] The purpose of this study was to investigate how a stretching torque affects muscular contractures. [Subjects] The subjects of this study were 48 male Wistar rats. [Methods] Subjects were divided into 4 groups as follows: Group 1 was the control; Group 2 had muscles in continuous fixation; Group 3 had muscles stretched in the direction of dorsiflexion by a spring balancer set at a torque of 0.3N for a period of 30 minutes after continuous fixation; and Group 4 had muscles stretched in the direction of dorsiflexion by a spring balancer set at a torque of 3.0N for a period of 30 minutes after continuous fixation. Joint fixation periods were for 2 and 4-weeks. Ankle joint range of motion and soleus flexibility were analyzed. [Results] For the 2-week joint fixation, soleus flexibility in Group 4 showed an increase compared with that of Group 3. For both fixation periods, range of motion in Group 4 showed an increase compared with that of Group 3. [Conclusion] For both fixation periods, stretching improved joint range of motion. In the 2-week joint fixation, soleus flexibility improved. However, soleus flexibility did not improve in the 4-week joint fixation.Key words: Muscular contracture, Stretching, Muscular flexibility  相似文献   
63.
Human mesenchymal stem cells (MSCs) were suspended in phosphate-buffered saline (PBS) and stored up to 24 h at 4 degrees C, 24 degrees C, and 37 degrees C. More than 80% viability was maintained at any temperature for at least 1 h, then gradually decreased over time. After 24 h, the viabilities at 4 degrees C, 24 degrees C, and 37 degrees C were about 81%, 70%, and 62%, respectively. The MSCs suspended/stored in PBS at 4 degrees C for 24 h also exhibited in vitro osteogenic differentiation capability as evidenced by mineralized matrix formation as well as high alkaline phosphatase activity when cultured in an osteogenic medium. Furthermore, in vivo implantation experiments using the MSCs also demonstrated new bone formation. Because MSCs are known to possess multipotential stem cell characteristics, these data indicate that human MSCs stored in PBS at 4 degrees C could be delivered to distant medical facilities for the purpose of hard tissue and other types of tissue regeneration therapy.  相似文献   
64.
Recent molecular studies show that Cryptosporidium parvum is composed of at least eight genotypes including zoonotic genotypes. Therefore, it is important to screen the genotypes of the isolates harbored in animals for the control of human cryptosporidiosis. The ferret is a popular pet, but also a reservoir of Cryptosporidium. Since the infectivity of zoonotic genotypes in ferrets remains unclear, there is a possibility these hosts harbor zoonotic genotypes. In the present study, we examined the genotypes of C. parvum isolates from ferrets in Japan using polymerase chain reaction direct sequencing. The sequences of the isolates examined clustered with the ferret-adapted genotype (ferret genotype). Our study suggests that ferrets harbor the ferret genotype which is conserved across geographical areas. Further study is required to determine whether ferrets are a significant reservoir for human cryptosporidiosis.  相似文献   
65.
Angioimmunoblastic T‐cell lymphoma (AITL) is a peripheral T‐cell lymphoma characterized by systemic disease with polymorphous infiltrate including macrophages. Although many studies of tumor‐associated macrophage (TAM) populations in various malignant tumors have been published, only a few have dealt with activation of macrophage phenotypes such as M1 and M2 in tumor tissue. Because M2 macrophages highly express CD163, we suspected that CD163 may be a useful marker for identification of activation of macrophage phenotypes in AITL. We performed a retrospective study of immunohistochemical expression using two markers for macrophages [CD68 (PG‐M1), CD163] and of the correlation of these expressions with overall survival of 42 AITL patients. The number of CD68‐positive cells in AITL tissues did not correlate with overall survival (P= 0.59), whereas the number of CD163‐positive cells and overall survival correlated to some extent (P= 0.08). Meanwhile, a higher ratio of CD163‐positive to CD68‐positive cells in AITL significantly correlated with worse overall survival (P= 0.036). Considering that this ratio reflects the proportion of macrophages polarized to the M2 phenotype, our findings indicate that activation of macrophages towards the M2 phenotype correlates with worse prognosis. Our findings indicate that the ratio of M2 macrophages expressed may be a useful marker for prognosis of AITL.  相似文献   
66.
BACKGROUND: Once food elimination is introduced, it is important to know for doctors when patients generally develop oral tolerance against eliminated food. To clarify the point, following study was conducted. METHODS: We analyzed 304 patient profiles with food allergy in our division between 1994 and 2001. The diagnosis of oral tolerance was determined by the results of food challenges or the accidental episodes of ingestion. RESULTS: By the age of 3 years old, 78% of food allergy patients with soybean, 63% of those with wheat, 60% of those with cow's milk, 51% of those with egg yolk, and 31% of those with egg white developed oral tolerance, respectively. IgE CAP RAST scores against cow's milk, egg yolk, and egg white in the patients without tolerance were significantly higher than those in the patients with tolerance. CONCLUSION: Patients developed oral tolerance firstly against soybean followed by wheat, cow's milk, egg yolk and egg white during the first 3 years of life. The specific IgE antibody levels against egg and cow's milk are important for the diagnosis of tolerance.  相似文献   
67.
68.
Developments in optical experimental techniques have helped in elucidating how blood flows through microvessels. Although initial developments were encouraging, studies on the flow properties of blood in microcirculation have been limited by several technical factors, such as poor spatial resolution and difficulty obtaining quantitative detailed measurements at such small scales. Recent advances in computing, microscopy, and digital image processing techniques have made it possible to combine a particle tracking velocimetry (PTV) system with a confocal microscope. We document the development of a confocal micro-PTV measurement system for capturing the dynamic flow behavior of red blood cells (RBCs) in concentrated suspensions. Measurements were performed at several depths through 100-μm glass capillaries. The confocal micro-PTV system was able to detect both translational and rotational motions of individual RBCs flowing in concentrated suspensions. Our results provide evidence that RBCs in dilute suspensions (3% hematocrit) tended to follow approximately linear trajectories, whereas RBCs in concentrated suspensions (20% hematocrit) exhibited transversal displacements of about 2% from the original path. Direct and quantitative measurements indicated that the plasma layer appeared to enhance the fluctuations in RBC trajectories owing to decreased obstruction in transversal movements caused by other RBCs. Using optical sectioning and subsequent image contrast and resolution enhancement, the system provides previously unobtainable information on the motion of RBCs, including the trajectories of two or more RBCs interacting in the same focal plane and RBC dispersion coefficients in different focal planes. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
69.
Tumor-associated macrophages (TAM) are known to possess the immunosuppressive M2 macrophage phenotype. They contribute to tumor growth, invasion, and metastasis by producing various mediators. Macrophages, especially M2 polarized macrophages, preferentially express CD163 and CD204, but few studies have investigated macrophage phenotypes in human ovarian tumors. The purpose of the present study was therefore to present results on macrophage differentiation in human ovarian serous and mucinous epithelial tumors. The method focused on immunostaining of paraffin-embedded tumor samples. Almost all macrophages infiltrating tumor tissues expressed CD163 and CD204, indicating the phenotypic shift toward M2 macrophage. The numbers of CD68-positive macrophages as well as of CD163- and CD204-positive macrophages in borderline and malignant tumors were significantly higher than in benign tumors. They correlated well with histological gradient of malignancy. Macrophage colony-stimulating factor (also known as colony-stimulating factor; CSF-1), which is one of the cytokines considered to induce TAM to polarize toward an M2 phenotype, was then evaluated. CSF-1 expression in malignant tumor cells was significantly higher than that in benign tumor cells and correlated with histological malignancy. These results suggest that CSF-1 derived from tumor tissues induces macrophages to shift toward the M2 phenotype, which is considered to promote tumor growth.  相似文献   
70.
Chronic smoking has been linked with alterations in endogenous pain regulation. These alterations may be pronounced when individuals quit smoking because nicotine withdrawal produces a variety of psychological and physiological symptoms. Smokers interested in quitting (n = 98) and nonsmokers (n = 37) completed a laboratory session including cold pressor test (CPT) and heat thermal pain. Smokers set a quit date and completed the session after 48 h of abstinence. Participants completed the pain assessments once after rest and once after stress. Cardiovascular and nicotine withdrawal measures were collected. Smokers showed blunted cardiovascular responses to stress relative to nonsmokers. Only nonsmokers had greater pain tolerance to CPT after stress than after rest. Lower systolic blood pressure was related to lower pain tolerance. These findings suggest that smoking withdrawal is associated with blunted stress response and increased pain sensitivity.  相似文献   
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