Prognostic model for hepatocellular carcinoma with time-dependent factors

The purpose of this study was to build a prognostic model of hepatocellular carcinoma (HCC) using time-dependent covariates to re-evaluate the prognosis at any stage of the disease. The subjects were consecutive HCC patients who were treated at our institute between 1995 and 2007. We constructed time-fixed and time-dependent prognostic models with a training group (n=336) and compared the prognostic abilities between conventional Cancer of the Liver Italian Program (CLIP) scores, Japan Integrated Staging (JIS) scores, an Okuda classification, and our prognostic models in the testing group (n=227) with the c-index. The time-dependent prognostic model consisted of main tumor size, tumor number, portal vein invasion, distant metastasis, alpha-fetoprotein, des-gamma-carboxy prothrombin (DCP), bilirubin, and albumin and the weighted scores were set for each factor depending on the hazard ratio for the prognosis. The prognostic index was determined by summing the scores. The c-index values for the CLIP scores, JIS scores, Okuda classification, and our time-dependent model were 0.741, 0.727, 0.609, and 0.870, respectively. These results indicate that our time-dependent model can estimate the prognosis of HCC more precisely than traditional time-fixed models and can be used to re-predict the prognosis of HCC.     

Chondrocyte distribution and cartilage regeneration in silk fibroin sponge

Chondrocytes distribution and cartilage formation in three types of fibroin sponges with different average pore sizes (40-80, 80-120 and 100-140 μm) was measured. The image processing was performed combining two methods to identify cells automatically: extraction of local maximum luminance and multi-threshold analysis. The results showed that initial accumulation of chondrocytes localized at surface area at 3 h in the small and medium-pore groups, however, the difference in the cell distributions become equivalent until 24 h after seeding. Cartilaginous tissue was well formed in each group at 21 days, and that in the smaller pore group tend to distribute at the surface area. Spherical tissues were located at the subsurface (200-600 μm below the surface) of the sponge in the medium- and large-pore groups at 21 days. Local cell aggregation was observed at 24 h at the same depth of the fibroin sponge as the spherical tissues observed at 21 days. These results suggest that the initial cell condensation process till 24 h after seeding play an important role in cartilage tissue formation.     

Further development of the rat Pig-a mutation assay: measuring rat Pig-a mutant bone marrow erythroids and a high throughput assay for mutant peripheral blood reticulocytes

Recent studies indicate that the Pig-a assay is a promising tool for evaluating in vivo mutagenicity. We have developed novel rat Pig-a assays that facilitate measuring mutant frequencies in two early arising populations of blood cells, bone marrow erythroids (BMEs) and peripheral blood (PB) reticulocytes (RETs). In these assays, bone marrow cells of erythroid origin and PB red blood cells (RBCs) were identified using an antibody against rat erythroid-specific marker HIS49. In addition, RETs were selectivity enriched from PB using magnetic separation of cells positive for CD71, a transferrin receptor expressed on the surface of BMEs and RETs, but not on the surface of mature RBCs. With magnetic enrichment, more than 1 x 10(6) CD71-positive RETs could be evaluated by flow cytometry for Pig-a mutant frequency within 5 to 8 min. CD59-deficient RET and BME frequencies of more than 100 x 10(-6) and 80 x 10(-6) were detected 1 week after treating rats with 40 mg/kg N-ethyl-N-nitrosourea; by comparison, the frequency of CD59-deficient total RBCs in these rats was 13.2 x 10(-6). The frequency of spontaneous Pig-a mutant RETs and BMEs was less than 5 x 10(-6) and 15 x 10(-6), respectively. Since approximately 98% of nucleated cells in the BME fraction were erythroblasts, it should be possible to use BMEs to determine the spectrum of CD59-deficient Pig-a mutations in cells of erythroid lineage. Conducting concurrent Pig-a assays on RETs and BMEs may be useful for evaluating the in vivo mutagenicity of chemicals, especially when prolonged mutant manifestation is not feasible or when the confirmation of mutation induction is necessary.     

Activation of the activin A-ALK-Smad pathway in systemic sclerosis

Systemic sclerosis (SSc) is a chronic disease of unknown etiology that is characterized by multiple tissue fibrosis. Transforming Growth Factor-beta (TGF-β) is thought to be the most important mediator that induces fibrosis. However, the molecular mechanisms by which fibrosis is induced have not been fully elucidated. In this study, the role of activin, a member of the TGF-β superfamily, was investigated in the pathogenesis of fibrosis in SSc. Serum activin A levels in patients with SSc were measured by ELISA, and the expression of the activin receptor type IB (ACVRIB/ALK4) and the activity of the signaling pathway via ACVRIB/ALK4 were investigated using western blotting. To evaluate a potential therapeutic strategy for SSc, we also attenuated the ACVRIB/ALK4 pathway using an inhibitor. Serum activin A levels were significantly higher in SSc patients than in normal controls. Activin A and ACVRIB/ALK4 expression were also higher in cultured SSc fibroblasts. Activin A stimulation induced phosphorylation of Smad2/3 and CTGF expression in SSc fibroblasts. Procollagen production and Col1α mRNA also increased upon stimulation by activin A. The basal level of Smad2/3 phosphorylation was higher in cultured SSc fibroblasts than in control cells, and treatment with the ALK4/5 inhibitor SB431542 prevented phosphorylation of Smad2/3 and CTGF expression. Furthermore, production of collagen was also induced by activin A. Activin A-ACVRIB/ALK4-Smad-dependent collagen production was augmented in SSc fibroblasts, suggesting the involvement of this signaling mechanism in SSc. Inhibition of the activin A-ACVRIB/ALK4-Smad pathway would be a new approach for the treatment of SSc.     

Atypical tumor-stromal fibroblasts in invasive ductal carcinomas of the breast treated with neoadjuvant therapy

Tumor-stromal fibroblasts have recently been reported to play important roles in the tumor progression of cancer in various organs. The purpose of the present study was to investigate whether any characteristic histologic features of tumor-stromal fibroblasts could accurately predict the outcome of 318 patients with invasive ductal carcinoma of the breast who had received neoadjuvant therapy. We observed a small number of tumor-stromal fibroblasts with characteristic nuclear features existing in the tumor stroma and named these cells "atypical tumor-stromal fibroblasts." We then assessed the absence or presence of atypical tumor-stromal fibroblasts in biopsy (taken before neoadjuvant therapy) and surgical (taken after neoadjuvant therapy) materials and analyzed the outcome predictive powers of the presence of atypical tumor-stromal fibroblasts in biopsy and surgical materials using multivariate analyses that included well-known clinicopathological factors. The multivariate analyses demonstrated that the presence of atypical tumor-stromal fibroblasts assessed using biopsy materials had significantly higher hazard ratios for tumor recurrence and tumor-related death in patients with nodal metastasis and also significantly higher hazard ratios for tumor recurrence and tumor-related death independent of the hormone receptor status of the tumors. The results of this study clearly indicated that the presence of atypical tumor-stromal fibroblasts, especially in biopsy materials, is significantly associated with tumor recurrence and the tumor-related death of patients with invasive ductal carcinoma of the breast who have received neoadjuvant therapy.     

Semi-quantitative and simulation analyses of effects of γ rays on determination of calibration factors of PET scanners with point-like (22)Na sources

The uncertainty of radioactivity concentrations measured with positron emission tomography (PET) scanners ultimately depends on the uncertainty of the calibration factors. A new practical calibration scheme using point-like (22)Na radioactive sources has been developed. The purpose of this study is to theoretically investigate the effects of the associated 1.275 MeV γ rays on the calibration factors. The physical processes affecting the coincidence data were categorized in order to derive approximate semi-quantitative formulae. Assuming the design parameters of some typical commercial PET scanners, the effects of the γ rays as relative deviations in the calibration factors were evaluated by semi-quantitative formulae and a Monte Carlo simulation. The relative deviations in the calibration factors were less than 4%, depending on the details of the PET scanners. The event losses due to rejecting multiple coincidence events of scattered γ rays had the strongest effect. The results from the semi-quantitative formulae and the Monte Carlo simulation were consistent and were useful in understanding the underlying mechanisms. The deviations are considered small enough to correct on the basis of precise Monte Carlo simulation. This study thus offers an important theoretical basis for the validity of the calibration method using point-like (22)Na radioactive sources.     

Impact of internal biliary drainage after pancreaticoduodenectomy

Background  Bile acid has an important role in protecting immune systems related to gut-associated lymphoid tissue. This study was designed to evaluate the effects of internal biliary drainage after a pancreaticoduodenectomy (PD) on postoperative nutrition and complications in a randomized study. Methods  The authors compared the morbidity, mortality, and postoperative nutritional status of 46 patients who had a hepaticojejunostomy (HJ) with a stented external biliary drainage (group E) or with a non-stented internal biliary drainage (group I) after a PD. Results  Systemic infection was recognized in four patients in group E, while no patients in group I. Transthyretin at postoperative 28 days in group I was 15.6 ± 6.2, higher than that in group E. Retinol-binding protein at postoperative 28 days in group I was 2.6 ± 1.0 and also higher than that in group E. Conclusion  HJ with no-stented internal biliary drainage was not associated with systemic infections and mortality, but showed the possibility of improving nutritional status.     

Functional outcomes after arthroscopic treatment of lateral epicondylitis

Background  The purpose of this study was to evaluate surgical outcomes of arthroscopic débridement for lateral epicondylitis using a validated, patient-assessed scoring system as well as conventional outcome measures. We also wanted to identify potential predictive factors that may be associated with the outcomes. Methods  A total of 20 elbows in 18 patients with chronic lateral epicondylitis who underwent arthroscopic surgery were included. There were nine men and nine women with a mean age of 54 years (range 42–71 years). Operative treatment consisted of débridement of the extensor carpi radialis brevis (ECRB) origin and resection of the radiocapitellar synovial plica interposed in the joint. Outcomes were assessed using a patient rating, visual analogue scale (VAS) pain score, the Japanese Orthopaedic Association (JOA) elbow score, and the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire. The average length of follow-up was 28 months (range 24–40 months). Results  After surgery, according to the patients’ reports, 14 of 20 elbows were much better, and 6 elbows were better. A mean preoperative VAS pain score at rest of 3.9 points improved to 0.3 points (P < 0.0001), and that during activity improved from 7.8 points to 0.9 points (P < 0.0001). The mean preoperative JOA elbow score of 29 points was improved to 90 points (P < 0.0001). The mean postoperative DASH score was 10.6 (range 0–50). Absent of T2-weighted high signal focus of the ECRB origin on preoperative magnetic resonance imaging (MRI) (P = 0.02) and receiving public assistance (P = 0.01) were significantly associated with worse DASH scores. Conclusions  Arthroscopic release was a satisfactory procedure for chronic lateral epicondylitis. Preoperative MRI of the ECRB origin and socioeconomic factors were significantly associated with postoperative residual symptoms evaluated with the DASH score.