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131.
Nagase analbuminemic rats (NARs) have a 7-base-pair deletion at the 5' splice site of the HI intron of the albumin gene. The level of immunohistochemically albumin-positive hepatocytes is about 1 per 10(5) cells in neonatal NARs, increases with age, and further increases with chronic oral treatment with 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB). The mechanisms involved in the increase in albumin-positive hepatocytes during aging of NARs and their treatment with 3'-MeDAB were analyzed. NARs were found to have four species of albumin mRNA: intact mRNA and those lacking the regions corresponding to exon H, exon G-H, and exon H-I. In 4-week-old NARs, the level of intact albumin mRNA was about 1/4000 of that in normal rats and mRNA lacking the exon H sequence was the major species. In aged and 3'-MeDAB-treated aged NARs, all four species of mRNA increased and the relative proportion of mRNAs lacking two exon sequences to mRNAs lacking one exon sequence was greatly increased, suggesting that aging is associated with changes of the splicing pattern and that 3'-MeDAB treatment enhanced these changes. In aged NARs and 3'-MeDAB-treated aged NARs, there was an increase in the amount of aberrant 60-kDa albumin. The 60-kDa protein could be a translation product of mRNAs lacking two exons, the amount of which increases in aged NARs and 3'-MeDAB-treated NARs.  相似文献   
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Aim: In Caucasians in northern Europe and North America, type 1 autoimmune hepatitis is characterized by susceptibility to human leukocyte antigens DR3 and DR4, and patients with zone III necrosis more frequently have an acute onset of the disease and a lower frequency of cirrhosis than those without. In Japanese patients, however, type 1 autoimmune hepatitis is primarily associated with DR4, and there are almost no DR3-positive patients. Thus, the clinical features of Japanese patients with type 1 autoimmune hepatitis and zone III necrosis may be different from those reported previously for Caucasians. Methods: We investigated 160 consecutive patients with type 1 autoimmune hepatitis (20 males and 140 females; median age, 55 years; range, 16-79 years). Results: Forty-seven patients (29%) had zone III necrosis, and these patients had lower serum levels of albumin and higher serum levels of total bilirubin, aspartate aminotransferaseand alanine aminotransferase. Histologically, zone III necrosis was found more frequently in patients with acute hepatitis than in those with chronic hepatitis. However, there was no difference in the frequency of cirrhosis between patients with and without zone III necrosis. In addition, normalization of serum alanine aminotransferase levels within six months after the introduction of corticosteroid treatment was slightly more frequent in patients with zone III necrosis (95% vs. 88%). Conclusion: In Japanese patients, zone III necrosis may reflect not only acute autoimmune hepatitis, but also acute exacerbation of pre-existing chronic disease. Furthermore, patients with zone III necrosis may respond better to corticosteroid treatment than those without.  相似文献   
134.
In lead optimization, it is difficult to estimate when an analog series might be saturated and synthesis of additional compounds would be unlikely to yield further progress. Rather than terminating a series, one often continues to generate analogs hoping to reach the final optimization goal, even if obstacles that are faced ultimately prove to be unsurmountable. Clearly, methodologies to better understand series progression and saturation are highly desirable. However, only a few approaches are currently available to monitor series progression and aid in decision making. Herein, we introduce a new computational method to assess progression saturation of an analog series by relating the properties of existing compounds to those of synthetic candidates and comparing their distributions in chemical space. The neighborhoods of analogs are analyzed and the distance relationships between existing and candidate compounds quantified. An intuitive dual scoring scheme makes it possible to characterize analog series and their degree of progression saturation.

Chemical space view of an analog series. Shown are inactive (red) and active (blue) analogs together with virtual candidate compounds (green) available to expand the series. Chemical neighborhoods of analogs are depicted in gray.  相似文献   
135.

Background

Various systematic reviews and/or meta-analyses examining the effects of pre- or postoperative exercise on body function or activity in patients undergoing total knee arthroplasty (TKA) have been published. However, the interventional period needed to at least improve outcomes is unknown.

Objective

The aim of this systematic review and meta-analysis was to investigate the exercise intervention period needed to effectively improve body function or activity before and after TKA in patients with knee osteoarthritis (OA).

Methods

Studies published until July 2017 were included in the review. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was applied to each meta-analysis to determine the quality of the evidence.

Results

Twenty-seven randomized controlled trials were identified. A meta-analysis indicated that exercises performed for 8 weeks after discharge in addition to standard postoperative intervention effectively improved body function as assessed using pain level; physical function, and stiffness on the Western Ontario and McMaster Universities Arthritis Index; extension strength; active knee flexion range of motion; timed up and go test; and gait speed.

Conclusion

Overall, we found low- to moderate-quality evidence that an 8-week exercise period was needed after discharge to improve body function and activity in patients with knee OA undergoing TKA.  相似文献   
136.
The objectives of this study were to evaluate dosimetric quality and acute toxicity of volumetric-modulated arc therapy (VMAT) and daily image guidance in high-risk prostate cancer patients. A total of 100 consecutive high-risk prostate cancer patients treated with definitive VMAT with prophylactic whole-pelvic radiotherapy (WPRT) were enrolled. All patients were treated with a double-arc VMAT plan delivering 52 Gy to the prostate planning target volume (PTV), while simultaneously delivering 46.8 Gy to the pelvic nodal PTV in 26 fractions, followed by a single-arc VMAT plan delivering 26 Gy to the prostate PTV in 13 fractions. Image-guided RT was performed with daily cone-beam computed tomography. Dose–volume parameters for the PTV and the organs at risk (OARs), total number of monitor units (MUs) and treatment time were evaluated. Acute toxicity was assessed using the Common Terminology Criteria for Adverse Events, version 4.0. All dosimetric parameters met the present plan acceptance criteria. Mean MU and treatment time were 471 and 146 s for double-arc VMAT, respectively, and were 520 and 76 s for single-arc VMAT, respectively. No Grade 3 or higher acute toxicity was reported. Acute Grade 2 proctitis, diarrhea, and genitourinary toxicity occurred in 12 patients (12%), 6 patients (6%) and 13 patients (13%), respectively. The present study demonstrated that VMAT for WPRT in prostate cancer results in favorable PTV coverage and OAR sparing with short treatment time and an acceptable rate of acute toxicity. These findings support the use of VMAT for delivering WPRT to high-risk prostate cancer patients.  相似文献   
137.
ABSTRACT

Purpose: To evaluate the cost-effectiveness for a screening interval longer than 1 year detecting diabetic retinopathy (DR) through the estimation of incremental costs per quality-adjusted life year (QALY) based on the best available clinical data in Japan.

Methods: A Markov model with a probabilistic cohort analysis was framed to calculate incremental costs per QALY gained by implementing a screening program detecting DR in Japan. A 1-year cycle length and population size of 50,000 with a 50-year time horizon (age 40–90 years) was used. Best available clinical data from publications and national surveillance data was used, and a model was designed including current diagnosis and management of DR with corresponding visual outcomes. One-way and probabilistic sensitivity analyses were performed considering uncertainties in the parameters.

Results: In the base-case analysis, the strategy with a screening program resulted in an incremental cost of 5,147 Japanese yen (¥; US$64.6) and incremental effectiveness of 0.0054 QALYs per person screened. The incremental cost-effectiveness ratio was ¥944,981 (US$11,857) per QALY. The simulation suggested that screening would result in a significant reduction in blindness in people aged 40 years or over (?16%). Sensitivity analyses suggested that in order to achieve both reductions in blindness and cost-effectiveness in Japan, the screening program should screen those aged 53–84 years, at intervals of 3 years or less.

Conclusions: An eye screening program in Japan would be cost-effective in detecting DR and preventing blindness from DR, even allowing for the uncertainties in estimates of costs, utility, and current management of DR.  相似文献   
138.
Contrast‐induced nephropathy (CIN) is considered to result from intrarenal vasoconstriction, and occurs more frequently in impaired than in normal kidneys. It was hypothesized that iodinated contrast media would markedly change renal blood flow and vascular resistance in functionally impaired kidneys. Thirty‐six patients were enrolled (32 men; mean age, 75.3 ± 7.6 years) undergoing diagnostic coronary angiography and were divided into two groups based on the presence of chronic kidney disease (CKD), defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min per 1.73 m2 (CKD and non‐CKD groups, n = 18 in both). Average peak velocity (APV) and renal artery resistance index (RI) were measured by Doppler flow wire before and after administration of the iodinated contrast media. The APV and the RI were positively and inversely correlated with the eGFR at baseline, respectively (APV, R = 0.545, P = 0.001; RI, R = ?0.627, P < 0.001). Mean RI was significantly higher (P = 0.015) and APV was significantly lower (P = 0.026) in the CKD than in the non‐CKD group. Both APV (P < 0.001) and RI (P = 0.002) were significantly changed following contrast media administration in the non‐CKD group, but not in the CKD group (APV, P = 0.258; RI, P = 0.707). Although renal arterial resistance was higher in patients with CKD, it was not affected by contrast media administration, suggesting that patients with CKD could have an attenuated response to contrast media.  相似文献   
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