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131.
132.
The circular dichroism of rhodopsin and lumirhodopsin   总被引:1,自引:0,他引:1  
We have measured the circular dichroism (CD) spectrum of rhodopsin from 220 to 650 nm. Besides the previously reported bands at 220, 335 and 485 nm, we have also observed a distinct band at 280 nm and shoulders at 270 and 300 nm. Upon cooling a mixture of rhodopsin and glycerol to ?76°C, there is no significant change in the circular dichroism spectrum. We then investigated the CD of the photoproduct of bleaching at this temperature, lumirhodopsin. The CD spectrum of lumirhodopsin was different depending on the detergent the rhodopsin was dissolved in, Ammonyx LO or Digitonin. In Ammonyx LO, the α-CD band was approximately as large as that of rhodopsin, the β-CD band was reduced by 80% and the 300-nm CD band increased about two- to three-fold. In Digitonin, the α-CD band was 45% as large as that of rhodopsin's α-CD band, the β-CD and the 300-nm CD bands were similar to those seen for lumirhodopsin in LO. The origin of the band at 300 nm is unknown. For rhodopsin in Ammonyx LO, the 220 nm band did not show a detectable change upon illumination, suggesting that there was no, or only a very small, protein conformational change in going from rhodopsin to lumirhodopsin.  相似文献   
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We investigated NY-ESO-1 and LAGE-1a mRNA expression in normal tissues and various types of cancer by quantitative real-time RT-PCR. In addition to their high expression in the testis, we observed a low expression of NY-ESO-1 mRNA in the placenta, pancreas and liver, and no expression in 12 other normal tissues. We also observed a low expression of LAGE-1a mRNA in the placenta and ovary, and marginal expression in 13 other normal tissues. In contrast to the previous finding that NY-ESO-1 and LAGE-1a mRNAs were mostly co-expressed in solid tumors, we found an independent expression of NY-ESO-1 and LAGE-1a mRNAs. NY-ESO-1 mRNA expression was mostly associated with LAGE-1a mRNA expression in esophageal and liver cancers, but not in prostate cancer. Immunohistochemistry (IHC) using NY-ESO-1-specific ES121 mAb showed that NY-ESO-1 protein was detected in 6 of 9 and 3 of 10 NY-ESO-1 mRNA-positive specimens from esophageal and liver cancers, respectively. NY-ESO-1 protein expression was correlated with the copy numbers of NY-ESO-1 mRNA. IHC was also performed using ES121 mAb and B9.8 mAb recognizing both NY-ESO-1 and LAGE-1a in 4 esophageal and 6 liver cancer specimens preferentially expressing LAGE-1a mRNA. B9.8-specific staining was observed weakly and focally in one liver cancer specimen expressing >10(5) copies of LAGE-1a mRNA.  相似文献   
134.
There have been reports of strong correlations between poor prognosis in various cancers and concomitant expression of urokinase-type plasminogen activator (uPA) and its surface receptor (uPAR). We and others have previously shown that the uPA system plays a significant role in a subset of head and neck squamous cell carcinoma. In the present study, we found that uPAR is required for invasion and metastasis of highly malignant oral cancer cells (OSC-19). Treating OSC-19 cells with antisense oligonucleotides (AS) targeting uPAR resulted in a dramatic decrease of uPAR mRNA expression. Furthermore, pretreatment with AS or siRNA targeting uPAR inhibited progression of OSC-19 cells in experimental models. These results suggest that overexpression of uPAR increases the invasiveness and metastasis of OSC-19 cells, and that uPAR is a promising therapeutic target for regulation of progression of oral cancer.  相似文献   
135.
BACKGROUND: Radiofrequency ablation (RFA) was introduced recently as a therapeutic modality for hepatocellular carcinoma (HCC), an alternative to percutaneous ethanol injection therapy (PEIT), which is coming into use worldwide. Previously reported treatment efficacy and complication rates have varied considerably. METHODS: Between February 1999 and February 2003, the authors performed 1000 treatments of RFA to 2140 HCC nodules in 664 patients with a cooled-tip electrode at the University of Tokyo Hospital (Tokyo, Japan). Short-term and long-term complications were analyzed by treatment and session basis. Cumulative survival was also assessed in 319 patients who received RFA as primary treatment (naive patients) and 345 patients who received RFA for recurrent tumor after previous treatment including resection, PEIT, microwave coagulation therapy, and transarterial embolization (nonnaive patients). RESULTS: A total of 40 major complications (4.0% per treatment, 1.9% per session) and 17 minor complications (1.7% per treatment, 0.82% per session) were observed during the observation period until March 31, 2004. There were no treatment-related deaths. Surgical intervention was required in one case each of bile peritonitis and duodenal perforation. The cumulative survival rates at 1, 2, 3, 4, and 5 years were 94.7%, 86.1%, 77.7%, 67.4%, and 54.3% for naive patients, whereas the cumulative survival rates were 91.8%, 75.6%, 62.4%, 53.7%, and 38.2% for nonnaive patients, respectively. CONCLUSIONS: The authors confirmed the safety and efficacy of RFA for HCC in a large-scale series and long-term prognosis was satisfactory.  相似文献   
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INTRODUCTION: An ABO-incompatible (ABO-I) living donor liver transplantation (LDLT) is a challenge. Until 2000 systemic multidrug immunosuppression and splenectomy was the gold standard with poor results. Application of local administration with prostagrandin E1 (PGE1) and steroids via a portal vein (PV) catheter dramatically improved the survival from 20% to 60% but PV thrombus became a problem (35%). To solve it, an hepatic arterial (HA) catheter was used instead of a PV catheter and splenectomy was omitted. Although the PV thrombus problem was resolved, the ABO antibody titers significantly increased, and two cases of uncontrollable humoral rejection (HR) were experienced. In this study, Rituximab was introduced instead of splenectomy to decrease the antibody. We report the efficacy of prophylaxis with Rituximab for ABO-I LDLT. METHODS: Eight patients received. Rituximab at 2 to 14 days before LDLT. During the operation, the spleen was preserved. Methylpredonisolone and PGE1 were administered via an HA catheter for 2 to 3 weeks after LDLT in addition to an immunosuppressive regimen consisting of tacrolimus and steroids. Antibody titers were measured serially. RESULT: There was no clinical HR. Two patients died of complications unrelated to HR. The antibody titer decreased compared to patients without splenectomy/rituximab. B cells (CD19) were depleted from peripheral blood for up to 3 months. Cytomegalovirus infections were decreased compared to patients with splenectomy (P = .085). CONCLUSION: Rituximab prophylaxis and HA infusion therapy prevented clinical HR, which may provide a breakthrough to overcome the ABO blood-type barrier in liver transplantation.  相似文献   
139.
Health-related quality of life (HRQOL; QOL hereafter) was evaluated in Japanese osteoporotic patients using three questionnaires; the SF-36 (MOS 36-Item Short-Form Health Survey; generic, profile-type), the EQ-5D (Euro Qol-5 Dimensions; generic, preference-based), and the JOQOL (Japanese Osteoporosis Quality of Life 1999; disease-targeted). The eight subscales and two summary scores of the SF-36 were impaired in these patients even after correction for age and sex. The scores on the EQ-5D and JOQOL correlated well with the subscales of the SF-36 that represent the physical aspects of physical function and bodily pain, which suggests that physical aspects are important determinants of overall QOL status in osteoporotic patients. Although the QOL scores did not correlate with bone mineral density, they were markedly influenced by the presence of vertebral fractures. In particular, the presence of two or more vertebral fractures greatly decreased the QOL scores. We then evaluated the QOL scores before and after treatment. The patients were either given calcium supplementation alone or calcium plus once-weekly elcatonin (Elcitonin, Asahi Kasei Pharma, Tokyo, Japan) injection. Elcatonin treatment markedly improved diverse aspects of the QOL, whereas calcium alone did not. The current data suggest that osteoporosis, especially in the presence of vertebral fracture, is associated with compromised QOL, and therapeutic intervention for osteoporosis should be evaluated in terms of QOL, as well as in terms of increases in bone mineral density and fracture prevention.  相似文献   
140.
BACKGROUND: Little is known about the epidemiologic features of different types of homeboundness among the elderly. PURPOSE: This cross-sectional study examined prevalence and characteristics of "type 1" and "type 2" homeboundness (see definitions below) among community-living older adults. METHODS: The subjects comprised all residents aged 65 years and over living in Yoita, Niigata Prefecture, and Hatoyama, Saitama Prefecture. Subject data on sociodemographics, and physical, mental and social functioning were collected through in-person interview. Persons were defined as being homebound if he/she went outdoors only once a week or less often. Homeboundness was further classified into "type 1" or "type 2", based on the hierarchical mobility level classification (levels 1 or 2 vs. levels 3, 4, or 5). "Type 1" homebound persons included those who could not get out into the neighborhood without assistance (i.e, levels 3, 4, or 5). "Type 2" included those who were homebound, though they could get out at least into the neighborhood unassisted (i.e., levels 1 or 2). We focused on characteristics of "type 1" and "type 2" homeboundness as compared with those of respective controls, ie., non-homebound persons within the same mobility categories. RESULTS: Out of the eligible subjects (1588 in Yoita, and 1135 in Hatoyama), 1544 and 1002 persons participated in the survey (response rates of 97.2% and 88.3%, respectively). Among the participants, "type 1" and "type 2" homeboundness was found for 4.1% and 5.4%, respectively, in Yoita, and 3.3% and 6.8% in Hatoyama. After adjustment for potential confounders such as age, gender and mobility level, we found a significant regional difference in the prevalence of "type 2" but not of "type 1" (OR of "type 2" for Hatoyama/Yoita 1.44; 95% CI 1.02-2.03). Both types of homeboundness increased with advancing age; "type 1" and "type 2" featured in over 10% of persons aged at least 85 years and 80 years, respectively. Even after controlling for potential confounders, "type 2" showed a higher prevalence with walking disability and incontinence, and reported lower self-rated health, more depressed mood, lower functional capacity and lower social functioning. "Type 1" showed a higher prevalence with fear of falls, but a lower prevalence with basic ADL disability and a high score for Intellectual Activity, indicating reduced self-efficacy. CONCLUSIONS: Prevalence of "type 1" and "type 2" homeboundness among community-living older adults differs depending on the residential area and age of the subjects. A substantial proportion of "type 2" homebound persons are at high risk of functional decline, indicating that "type 2" as well as "type 1" homebound persons need care-preventive programs.  相似文献   
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