Fatigue Properties of Hot-Dip Galvanized AISI 1020 Normalized Steel in Tension–Compression and Tension–Tension Loading

Since hot-dip galvanizing causes a heat effect on cold-worked steel substrate and produces a coating layer comprised of distinct phases with varying mechanical properties, the fatigue mechanism of hot-dip galvanized steel is very complex and hard to clarify. In this study, AISI 1020 steel that has been normalized to minimize susceptibility to the heat effect was used to clarify the effect of the galvanizing layer on the tensile and fatigue properties. The galvanizing layer causes a reduction in the yield point, tensile strength, and fatigue strength. The reduction in the fatigue strength was more significant in the high cycle fatigue at R = 0.5 and 0.01 and in the low cycle fatigue at R = 0.5. The galvanizing layer seems to have very little effect on the fatigue strength at R = −1.0 in the low and high cycle fatigue. Since the fatigue strengths at R = 0.01 and −1.0 in the low cycle fatigue were strongly related to the tensile strength of the substrate, the cracking of galvanized steel was different than that of non-galvanized steel. The fatigue strength of galvanized steel at R = 0.5 dropped remarkably in the low cycle fatigue in comparison to the non-galvanized steel, and many cracks clearly occurred in the galvanizing layer. The galvanizing layer reduced the fatigue strength only under tension–tension loading. We believe that the findings in this study will be useful in the fatigue design of hot-dip galvanized steel.     

Abnormal expression of BRCA1 and BRCA1-interactive DNA-repair proteins in breast carcinomas

Breast cancer is one of the most common malignancies among women. The molecular mechanisms involved in breast carcinogenesis, however, remain to be elucidated. Although somatic mutation of BRCA1 is rare, BRCA1 protein expression is reduced in about 30% of sporadic breast carcinomas (Yoshikawa et al., Clin. Cancer Res., 5:1249-1261, 1999), indicating its possible involvement even in sporadic breast carcinogenesis. Among the BRCA1-interactive proteins are hRAD51 (a human homologue of Escherichia coli rec A protein), BARD1 (BRCA1-associated RING domain 1) and p53, all of which are involved in DNA repair. We have analyzed the expression patterns of the hRAD51, BARD1 and p53 proteins in five breast cancer cell lines, including a BRCA1-deficient cell line, and in 179 breast cancer tissue samples from Japanese women, including 113 sporadic, 47 hereditary (i.e., BRCA1 status unknown), and 19 BRCA1-associated cases. Of the 179 breast carcinomas, fifty-four (30%) exhibited reduced hRAD51 expression, and sixty-two (35%) exhibited p53 overexpression. On the other hand, reduced expression level of BARD1, and of hMSH2 and hMLH1, which are components of DNA mismatch-repair pathway and are involved in colorectal carcinogenesis, was observed respectively in only 10 (6%), 8 (5%) and 3 (2%) cases. The overall frequency of sporadic breast carcinomas with abnormal expression of either BRCA1 or the BRCA1-interactive proteins was 67% (76/113). These results indicate that there may be an important role for the BRCA1-associated DNA-repair pathway, not only in BRCA1-associated breast carcinomas, but also in sporadic breast carcinomas.     

A case of lupus-associated pancreatitis with ruptured pseudoaneurysms

Pancreatitis is a relatively rare complication in systemic lupus erythematosus (SLE). Herein we report a case of SLE with the initial development of acute pancreatitis, subsequently complicated by bleeding pseudoaneurysms. A 55-year-old Japanese woman was admitted to our hospital for the treatment of SLE. During the course of treatment, she complained of upper abdominal pain. An abdominal computed tomography (CT) scan showed that the pancreas was diffusely enlarged, and she was diagnosed with acute pancreatitis. Her pancreatitis was resistant to glucocorticoid therapy and was subsequently associated with pancreatic pseudocysts and recurrent rupture of the pseudoaneurysms. After surgical drainage of the hemorrhagic pseudocysts, the patient’s clinical condition gradually improved with intensive therapies. Our case indicates that lupus pancreatitis can be associated with the potentially fatal complication of recurrent bleeding of pseudoaneurysms.     

Visceral adipose tissue level,as estimated by the bioimpedance analysis method,is associated with impaired lung function

Aims/Introduction: It has been reported that metabolic syndrome is associated with impaired lung function, and abdominal obesity is regarded as the most important determinant of this association. We evaluated the association between a component of metabolic syndrome, indices of body composition, including the total adipose tissue content, lean bodyweight and visceral adipose tissue content, as assessed by bioimpedance analysis, and lung function. Materials and Methods: A total of 516 participants responded to our questionnaire to determine the smoking status and history of past diseases. Waist circumference, height, bodyweight, percent forced expiratory volume in 1 s (%FEV1) and percent forced vital capacity (%FVC) were measured. Fasting blood samples were obtained to determine the serum levels of high‐density lipoprotein and triglyceride, and also the blood glucose. The body composition, including the total adipose tissue content and lean bodyweight, was measured, and the visceral adipose tissue content was estimated as the visceral adipose tissue level, by the bioimpedance analysis method. Results: Waist circumference, estimated visceral adipose tissue level and blood pressure were significantly associated with the %FEV1, and the serum high‐density lipoprotein cholesterol was significantly associated with the %FVC in men, after adjustment for age, smoking history, and past histories of bronchial asthma and ischemic heart disease. However, this association was not detected in women. Conclusions: We found an association between the visceral adipose tissue level as estimated by the bioimpedance analysis method and lung function. ( J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00189.x, 2011)     

Risk factors for the local recurrence of hepatocellular carcinoma after a single session of percutaneous radiofrequency ablation

Background Radiofrequency ablation (RFA) is a new, minimally invasive treatment for hepatocellular carcinoma (HCC). However, there is little available information regarding local recurrence after a single session of RFA with a single electrode insertion.Methods From February 1999 to September 2001, we treated 104 HCC tumors with an expandable needle with four hooks. Ninety-nine of the 104 tumors were successfully treated by single-session RFA with a single electrode insertion. We investigated the relationships between pretreatment factors (tumor size, tumor staining, tumor capsule, and tumor location) and local recurrence in these 99 tumors.Results The mean size of the 99 tumors was 21.5mm in diameter (range, 10 to 33mm). The overall local recurrence rates were 9.7%, 15.4%, and 20.4%, at 1, 2, and 3 years, respectively. For small tumors (smaller than 25mm), the local recurrence rates at 1, 2, and 3 years were 4.0%, 8.0%, and 14.6%, respectively. The local recurrence rates were 21.1% and 32.3% at 1 and 2 years, respectively, for large tumors (25mm or larger), and at 3 years the rate was over 50% for tumors located close to the liver surface. Tumor size and tumor location relative to the liver surface were significantly associated with a higher local recurrence rate. However, other variables tested showed no significant relationship to the local recurrence rate.Conclusions This study demonstrated that both tumor size and location relative to the liver surface influence the local efficacy of single-session RFA with a single electrode insertion.     

Secretory units of islets in transplantation index is a useful predictor of insulin requirement in Japanese type 2 diabetic patients

Aims/Introduction

The objective of the present study was to clarify the validity of β‐cell function‐related parameters for predicting the insulin requirement of Japanese type 2 diabetic patients.

Materials and Methods

In 188 patients with type 2 diabetes who had been admitted to the University of Toyama Hospital (Toyama, Japan) without receiving insulin therapy, we carried out a cross‐sectional study examining the relationship between the homeostasis model assessment of β‐cell function (HOMA‐β) and C‐peptide‐based indices, and also carried out a retrospective study to examine the utility for predicting insulin requirement of several β ‐cell function‐related indices using a receiver operating characteristic (ROC) curve analysis.

Results

The secretory units of islets in transplantation index (SUIT) had the strongest correlation with HOMA‐β, followed by the fasting serum C‐peptide immunoreactivity index (CPI); the fasting serum C‐peptide immunoreactivity itself (F‐CPR) had the least correlation. The CPI, HOMA‐β and SUIT were significantly lower in the insulin‐requiring group than in the non‐insulin‐requiring group, even after adjustments for confounding factors (P < 0.01). The areas under the ROC curve for insulin requirement were 0.622, 0.774, 0.808, and 0.759 for F‐CPR, CPI, SUIT, and HOMA‐β, respectively. The cut‐off values of SUIT, CPI, and HOMA‐β for an over 80% specificity for the prediction of insulin therapy were 23.5, 1.00, and 14.9, respectively.

Conclusions

The present study shows that SUIT is the best predictor of insulin requirement among these β‐cell function‐related markers.     

Double high-dose chemotherapy supported by autologous transplantation of peripheral blood stem cells for treatment of an elderly patient with small-cell lung cancer

We report a 62-year-old male with extensive disease small-cell lung cancer (SCLC) who was successfully treated with double high-dose chemotherapy supported by autologous peripheral blood stem cell transplantation (auto-PBSCT). This patient achieved a partial response with 3 cycles of induction chemotherapy. After the peripheral blood stem cell mobilization, two cycles of high-dose ICE regimen (ifosfamide 3,000 mg/m2 at days 1 to 5, carboplatin 400 mg/m2 at days 1, 3, 5, and etoposide 500 mg/m2 at days 1, 3, 5) could be given with further regression of the tumor and acceptable toxicities. This successful case suggests the feasibility of double high-dose ICE with auto-PBSCT in elderly patients with SCLC.     

CD45 tyrosine phosphatase inhibits erythroid differentiation of umbilical cord blood CD34+ cells associated with selective inactivation of Lyn

CD45 is a membrane-associated tyrosine phosphatase that dephosphorylates Src family kinases and Janus kinases (JAKs). To clarify the role of CD45 in hematopoietic differentiation, we examined the effects of anti-CD45 monoclonal antibody NU-L(PAN) on the proliferation and differentiation of umbilical cord blood CD34(+) cells. NU-L(PAN) showed a prominent inhibition of the proliferation of CD34(+) cells induced by the mouse bone marrow stromal cell line MS-5 or erythropoietin (EPO). However, NU-L(PAN) did not affect the proliferation induced by interleukin 3. NU-L(PAN) also inhibited MS-5-induced or EPO-induced erythroid differentiation of CD34(+) cells. The cells stimulated with EPO in the presence of NU-L(PAN) morphologically showed differentiation arrest at the stage of basophilic erythroblasts after 11 days of culture, whereas the cells treated with EPO without NU-L(PAN) differentiated into mature red blood cells. The Src family kinase Lyn and JAK2 were phosphorylated when erythroblasts obtained after 4 days of culture of CD34(+) cells in the presence of EPO were restimulated with EPO. Overnight NU-L(PAN) treatment before addition of EPO reduced the phosphorylation of Lyn but not that of JAK2. Simultaneously, the enhancement of Lyn kinase activity after restimulation with EPO was reduced by NU-L(PAN) treatment. These results indicate selective inactivation of Lyn by CD45 activated with NU-L(PAN) and could partly explain the inhibitory mechanism on erythropoiesis exhibited by EPO. These findings suggest that CD45 may play a pivotal role in erythropoiesis.     

Expression and responsiveness of human interleukin-18 receptor (IL-18R) on hematopoietic cell lines.

Interleukin-18 (IL-18) is a new inflammatory cytokine sharing biological functions with IL-12. The human IL-18 receptor (IL-18R) was recently identified and was found to be expressed on normal peripheral blood lymphocytes. To further characterize IL-18R, we analyzed IL-18R expression using a series of human hematopoietic cell lines selected from various cell lineages. We found the IL-18R expression on cells of T and B lineages as expected from analysis on normal cells. The IL-18R expression, however, was found not to be restricted to any specific maturation stages of T and B cells. In addition, we detected IL-18R expression in myeloid, monocytoid, erythroid and megakaryocytic cell lines, indicating that normal counterparts of these cell lineages could express IL-18R and participate in in vivo reactions caused by IL-18. Biochemical studies showed that IL-18R proteins exist as heterogeneous molecules ranging from 60 to 110 kDa. Deglycosylation experiments indicated that the heterogeneity could not be explained only by a difference in glycosylation. We also found that tumor necrosis factor-alpha (TNF-alpha) modulated the IL-18R expression, which implies an important in vivo effect of TNF-alpha on IL-18-induced reaction. Analyzing the responsiveness of IL-18R, we found that only KG-1 responded to IL-18 stimulation. This suggests that certain inhibitory mechanisms of IL-18 responsive genes are involved in the all IL-18R-positive cell lines except KG-1.