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21.
To develop novel biodegradable biomedical materials, polylactide-grafted dextrans (Dex-g-PLA)s having various lengths, numbers of graft chains and sugar units were synthesized using the trimethylsilyl (TMS) protection method. To explore the possibility of using Dex-g-PLA as a biomedical soft-material, the contact angle, cell attachment and protein adsorption properties of the films prepared from these biodegradable and amphiphilic graft co-polymers were investigated. The poly-L-lactide (PLLA) film did not absorb water at all because of its high hydrophobicity, while the graft co-polymer films started immediately to swell after immersion in PBS. The percentage of water absorption at equilibrium increased with increasing sugar unit content. The receding contact angle of the Dex-g-PLA films against water was smaller than that of the PLLA film. The receding contact angle of Dex-g-PLA films against water decreased with increasing the sugar unit content. The top surface of the Dex-g-PLA film was suggested to be covered with hydrophilic Dex segments by means of annealing in water and to afford the wettable surface. Such a wettable surface led to the suppression of cell attachment and protein adsorption onto the film.  相似文献   
22.
BACKGROUND: Although there have been numerous reports in personality of mood disorders, there have been few reports in regard with personality of winter seasonal affective disorder (SAD). Furthermore, no reports have been published concerning summer SAD personality characteristics. Thus, this study was conducted to assess the personality of winter and summer SAD using Tri-dimensional Personality Questionnaire (TPQ) that have been used in a variety of mental disorders. METHODS: A total of 6135 Japanese were evaluated with TPQ, the Seasonal Pattern Assessment Questionnaire (SPAQ) and the Self-rating Depression Scale (SDS). Winter, summer and non-SAD groups were classified by SPAQ. We compared the difference of personality trait among these three groups in consideration of gender, age and SDS score influence. RESULTS: Winter SAD demonstrated higher "Novelty Seeking" and "Harm Avoidance"; summer SAD showed higher "Harm Avoidance" than the non-SAD group. "Harm Avoidance" in both SAD groups was re-analyzed using SDS score as a covariate, and "Novelty Seeking" in winter SAD using age as a covariate. As a result, the significance of high "Novelty Seeking" and high "Harm Avoidance" in winter SAD was excluded. However, "Harm Avoidance" remained the significant difference between summer and non-SAD. LIMITATION: SAD was diagnosed only by SPAQ and not by interview. The state-dependency of "Harm Avoidance" was not confirmed in identical patients over lapse of time. CONCLUSION: Patients with winter SAD have high "Harm Avoidance" dependent on the depressive state that is in accordance with non-seasonal depression. Patients with summer SAD have high "Harm Avoidance" possibly independent from the depressive state.  相似文献   
23.
Noonan syndrome (NS) is characterized by short stature, characteristic facial features, and heart defects. Recently, missense mutations of PTPN11, the gene encoding protein tyrosine phosphatase (PTP) SHP-2, were identified in patients with NS. Further, somatic mutations in PTPN11 were detected in childhood leukemia. Recent studies showed that the phosphatase activities of five mutations identified in NS and juvenile myelomonocytic leukemia (JMML) were increased. However, the functional properties of the other mutations remain unidentified. In this study, in order to clarify the differences between the mutations identified in NS and leukemia, we examined the phosphatase activity of 14 mutants of SHP-2. We identified nine mutations, including a novel F71I mutation, in 16 of 41 NS patients and two mutations, including a novel G503V mutation, in three of 29 patients with leukemia. Immune complex phosphatase assays of individual mutants transfected in COS7 cells showed that ten mutants identified in NS and four mutants in leukemia showed 1.4-fold to 12.7-fold increased activation compared with wild-type SHP-2. These results suggest that the pathogenesis of NS and leukemia is associated with enhanced phosphatase activity of mutant SHP-2. A comparison of the phosphatase activity in each mutant and a review of previously reported cases showed that high phosphatase activity observed in mutations at codons 61, 71, 72, and 76 was significantly associated with leukemogenesis.  相似文献   
24.
The present study tested whether a gene-transfer based upon the retrograde axonal transport of the lacZ adenovirus is effective in the spinal descending tracts of the adult mouse. A small volume of a replication-defective recombinant adenovirus encoding E. coli beta-galactosidase was injected into the upper lumbar cord, and, seven days later, the mice were transcardially perfused by a fixative solution. X-gal staining of coronal or sagittal sections of the spinal cord and the brain revealed that many sites of origin for rubrospinal, vestibulospinal, and reticulospinal tracts were retrogradely labeled, whereas few of the corticospinal tract neurons were retrogradely labeled. Ependymal cells surrounding the central canal of the spinal cord, which were located far from the injection site, showed a high expression of beta-galactosidase activity. Motoneurons around the injection site were strongly stained by X-gal staining, and their axons in the ventral root were anterogradely labeled. Afferent fibers in the dorsal root were labeled by the transganglionic transport of beta-galactosidase. To examine the efficacy of the uptake and retrograde transport of HRP and adenovirus, we injected a mixed solution of 10% HRP and recombinant adenovirus. The number of HRP-labeled corticospinal neurons overwhelmed the number of X-gal stained ones, while the numbers of HRP-labeled rubrospinal and subcoeruleus-spinal neurons were smaller in comparison with the numbers of beta-galactosidase-positive counterparts. The present study revealed that the origins for the spinal descending tracts except for corticospinal neurons could be efficiently gene-transferred by the retrograde infection of a recombinant adenovirus. Such a difference in efficacy of retrograde infection among the spinal descending tracts is practically important when an adenovirus-mediated gene transfer is designed to treat certain neurological diseases affecting the spinal descending tracts.  相似文献   
25.
Osteopenia/osteoporosis and sarcopenia are common geriatric diseases among older adults and harm activities of daily living (ADL) and quality of life (QOL). Osteosarcopenia is a unique syndrome that is a concomitant of both osteopenia/osteoporosis and sarcopenia. This review aimed to summarize the related factors and clinical outcomes of osteosarcopenia to facilitate understanding, evaluation, prevention, treatment, and further research on osteosarcopenia. We searched the literature to include meta-analyses, reviews, and clinical trials. The prevalence of osteosarcopenia among community-dwelling older adults is significantly higher in female (up to 64.3%) compared to male (8–11%). Osteosarcopenia is a risk factor for death, fractures, and falls based on longitudinal studies. However, the associations between osteosarcopenia and many other factors have been derived based on cross-sectional studies, so the causal relationship is not clear. Few studies of osteosarcopenia in hospitals have been conducted. Osteosarcopenia is a new concept and has not yet been fully researched its relationship to clinical outcomes. Longitudinal studies and high-quality interventional studies are warranted in the future.  相似文献   
26.
Background: Nevus of Ota is common in Japanese women, but most patients are not examined ophthalmologically. Methods: We performed ophthalmologic examinations on 16 Japanese women who had had bluish pigmentation in the periorbital region, sclera, and conjunctiva since birth. Results: Fifteen patients had unilateral involvement, and one had bilateral lesions. The visual acuities were good, and the intraocular pressures were within normal range. All patients had a negative family history. Three patients had light pigmentation in the optic disc in the affected eye. Conclusion: We believe that optic disc pigmentation associated with nevus of Ota, as found in these three patients, may be common but have been rarely described.  相似文献   
27.
Background. Exact clinical staging before treatment of esophageal cancer has become increasingly important in the evaluation and comparison of the results of different treatment modalities, including surgery, chemotherapy, and radiotherapy.

Methods. The accuracy of preoperative tumor staging by using an esophagography, esophagoscopy, percutaneous and endoscopic ultrasonography, and computed tomography was assessed in 224 patients with resectable esophageal cancer. The results of tumor staging by these tests were compared prospectively with the pathologic stage of the esophagectomy specimens with respect to the T and N categories defined by the International Union Against Cancer TNM classification.

Results. For the T category, the overall accuracy was 80%. For the N category, overall accuracy was 72%, with a sensitivity of 78%, a specificity of 60%, and a positive predictive value of 78%. Overall, the accuracy of stage grouping was 56%.

Conclusions. Either the T or N categories can be predicted reliably by clinical staging techniques. However, the preoperative stage grouping might not be valid in resectable, localized esophageal cancer.  相似文献   

28.
Prostate-specific antigen values provide important and unique information about prostate cancer to clinicians. However, there is conflicting information about the prognostic significance of the dynamics of PSA decline and elevation after treatment. To provide further insight into the dynamics of PSA as prognostic factors, we herein studied various PSA values as possible prognostic factors in 93 patients with prostate cancer treated with endocrine therapy. Thirteen (14.0%) had stage B tumors, 20 (21.5%) had stage C tumors, and 60 (64.5%) had stage D tumors. The overall 5-year survival rate was 41.2%. Relapse was observed in 32 (34.4%) patients. The influence of pre- and post-treatment PSA (both absolute and percentage values) on survival was analyzed. Normalization of PSA value was associated with prolonged survival regardless of interval to reach the lowest PSA level. The absolute value of PSA at 3 or 6 months following treatment was a significant discriminator, while the pre-treatment PSA level and percentage values of post-treatment PSA were not. These data show that the PSA nadir and PSA value at 3 or 6 months following treatment provide important prognostic information.  相似文献   
29.
30.
We investigated the skeletal muscle voltage-gated chloride channel gene (CLCN1) in two unrelated Japanese patients with Becker's myotonia congenita. The non-myotonic parents of each patient were consanguineous. The proband of each family shares generalized myotonia, transient weakness after rest, and leg muscle hypertrophy. However, the disease severity related to the degree of myotonia differed, even in view of the response to long train nerve stimulation tests. CLCN1 gene analysis revealed a novel Ala659Val missense mutation identified to be homozygous in the more severe patient, while a novel Gln445Stop nonsense mutation was present in the other patient. Both mutations were absent in 90 Japanese normal controls. This is the first report of Japanese cases of Becker's myotonia congenita with CLCN1 gene mutations.  相似文献   
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