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Uptake of dehydroascorbic acid (DHA) was studied in two types of dog erythrocytes with high GSH and normal GSH levels. Compared with ascorbic acid uptake, DHA produced a much greater ascorbic acid accumulation in dog erythrocytes. Both dog erythrocytes showed a concentration dependence of DHA uptake, and cellular ascorbic acid concentrations were significantly higher in high-GSH cells than in normal-GSH cells. Glucose and cytochalasin B inhibited DHA uptake. This suggests that DHA enters dog erythrocytes predominantly by the facilitated glucose transporter, particularly by the Glut 1 glucose transporter. The rate of glucose uptake was quite similar in the two types of cells. Compared with normal-GSH cells, high-GSH cells were more resistant to oxidative stress induced by high concentration of DHA. As a rapid entry of DHA inflicts on cells a heavy demand for GSH for its reduction to ascorbic acid, high-GSH cells containing a larger reserve of GSH have an advantage over normal-GSH cells in both ascorbic acid accumulation and resisting oxidative stress produced by DHA.  相似文献   
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Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients.  相似文献   
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In a phase II clinical trial to test the ability of recombinant human erythropoietin (r-HuEPO) to reverse the anemia of patients undergoing hemodialysis, the changes of enzyme activity in red blood cells were evaluated in 5 hemodialysis anemic patients who were treated with r-HuEPO. Concerning the activity levels measured, the following conclusions are drawn. 1) HK, ALD, TPI, G6PD and 6PGD were statistically significantly increased at the time when the hematocrit has risen by 8% with the use of r-HuEPO. 2) The enzyme activity levels of PFK, GA3PD, MPGM, ENOL, PK, GR and ADA were higher than normal already before the r-HuEPO treatment. 3) The increases of HK and G6PD by r-HuEPO, as age dependent enzymes, may reflect the generation of young red blood cells. 4) In view of the fact that they are related to ATP production in the glycolysis cycle, we infer that increases of red blood cell enzymes by r-HuEPO may play at least some part in bringing a sensation of "well-being" to severely anemic patients undergoing hemodialysis.  相似文献   
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We aimed to evaluate the utility of a simplified ultrasonography (US) scoring system, which is desired in daily clinical practice, among patients with rheumatoid arthritis (RA) receiving biological/targeted synthetic disease-modifying antirheumatic drugs (DMARDs).A total of 289 Japanese patients with RA who were started on tumor necrosis factor inhibitors, abatacept, tocilizumab, or Janus kinase inhibitors between June 2013 and April 2019 at one of the 15 participating rheumatology centers were reviewed. We performed US assessment of articular synovia over 22 joints among bilateral wrist and finger joints, and the 22-joint (22j)-GS and 22-joint (22j)-PD scores were evaluated as an indicator of US activity using the sum of the GS and PD scores, respectively.The top 6 most affected joints included the bilateral wrist and second/third metacarpophalangeal joints. Therefore, 6-joint (6j)-GS and -PD scores were defined as the sum of the GS and PD scores from the 6 synovial sites over the aforementioned 6 joints, respectively. Although the 22j- or 6j-US scores were significantly correlated with DAS28-ESR or -CRP scores, the correlations were weak. Conversely, 6j-US scores were significantly and strongly correlated with 22j-US scores not only at baseline but also after therapy initiation.Using a multicenter cohort data, our results indicated that a simplified US scoring system could be adequately tolerated during any disease course among patients with RA receiving biological/targeted synthetic DMARDs.  相似文献   
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In the present study, we reviewed the effect of post-transplant double filtration plasmapheresis (DFPP) on recurrent focal segmental glomerulosclerosis (FSGS) in the transplanted kidney allograft. Sixteen patients with post-transplant recurrent FSGS were enrolled in this study. Out of 16 patients with recurrent FSGS after transplantation, five did not receive DFPP and lost their grafts, while 11 did receive DFPP and four of these patients lost their grafts. Seven patients were able to maintain normal renal function for an average observation period of 57.1 +/- 40.7 months (range 7-125 months). In five patients who had a significant reduction in urinary protein after DFPP, the urinary protein level decreased from 26.60 +/- 23.05 g/day (range 3.34-62.6 g/day) to 2.95 +/- 3.42 g/day (range 0.02-8.64 g/day) and renal function was maintained. The beneficial effects of DFPP on graft outcome were more likely to occur if the patients experienced a marked drop in urinary excretion. Thus, post-transplant DFPP appears to be effective for reducing urinary protein levels and improving long-term graft survival. With the small numbers in this trial, however, none of the findings were statistically significant. We recommend the use of post-transplant DFPP to prevent the progression of recurrent FSGS.  相似文献   
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Early morning and 24 h urine samples and serum were collected daily throughout the menstrual cycle in women. Urinary oestradiol-17-glucosiduronate (E2-17-G) was measured with a direct radioimmunoassay whose antiserum had been prepared against E2-17-G-[C-6]-bovine serum albumin conjugate and was very specific. On the average, E2-17-G in early morning and 24 h urine samples showed a prominent peak one day before the peak of urinary LH. The time relationship between these urinary E2-17-G and serum E2 levels and peaks was also investigated.  相似文献   
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