Analysis of microstructural effects on mechanical properties of copper alloys

With the aim of obtaining copper alloys with favorable mechanical properties (high strength and high ductility) for various engineering applications, the microstructural characteristics of two conventional copper alloys — an aluminum bronze (AlBC; Cu–Al9.3–Fe3.8–Ni2–Mn0.8) and a brass (HB: Cu–Al4–Zn25–Fe3–Mn3.8) — and a recently developed aluminum bronze (CADZ: Cu–Al10.5–Fe3.1–Ni3.5–Mn1.1–Sn3.7), were controlled by subjecting the alloys to two different processes (rolling and casting) under various conditions. For the rolling process, the rolling rate and temperature were varied, whereas for the casting process, the solidification rate was varied. Microstructural characteristics, as examined by electron backscatter diffraction analysis, were found to differ among the alloys. Complicated microstructures formed in CADZ led to high hardness and high tensile strength (σUTS), but low ductility (εf). For CADZ, casting at a high solidification rate allowed an increase in ductility to be obtained as a result of fine-grained structure and low internal stress. In contrast, high ductility (with a fracture strain of more than 30%) was found for both cast AlBC and cast HB; moreover, both of these alloys possessed high tensile strength when produced by warm rolling at 473 K. For CADZ, on the other hand, no clear effect of rolling on tensile strength could be found, owing to the many microcracks caused by its brittleness. The results of this study indicate that copper alloys with excellent mechanical properties can be produced. This is especially the case for the conventional alloys, with a high tensile strength σUTS = 900 MPa and a high fracture strain εf = 10% being obtained for warm-rolled brass

A Prospective Observational Study on Effect of Short-Term Periodic Steroid Premedication on Bone Metabolism in Gastrointestinal Cancer (ESPRESSO-01)

Background. A multicenter prospective observational study evaluated the effect of gastrointestinal cancer chemotherapy with short‐term periodic steroid premedication on bone metabolism. Patients and Methods. Seventy‐four patients undergoing chemotherapy for gastrointestinal cancer were studied. The primary endpoints were changes in bone mineral densities (BMDs) and metabolic bone turnover 16 weeks after initiation of chemotherapy. BMDs, measured by dual‐energy x‐ray absorptiometry, and serum cross‐linked N‐telopeptides of type I collagen (sNTX), and bone alkaline phosphatase (sBAP) were assessed for evaluation of bone resorption and formation, respectively. Results. In 74.3% (55/74) of the patients, BMDs were significantly reduced at 16 weeks relative to baseline. The percent changes of BMD were -1.89% (95% confidence interval [CI], -2.67% to -1.11%: p < .0001) in the lumbar spine, -2.24% (95% CI, -3.59% to -0.89%: p = .002) in the total hip, and -2.05% (95% CI, -3.11% to -0.99%: p < .0001) in the femoral neck. Although there was no significant difference in sNTX levels during 16 weeks (p = .136), there was a significant increase in sBAP levels (p = .010). Decreased BMD was significantly linked to number of chemotherapy cycles (p = .02). There were no significant correlations between changes in BMDs and the primary site of malignancy, chemotherapy regimens, total cumulative steroid dose, steroid dose intensity, and additive steroid usage. Conclusion. Gastrointestinal cancer chemotherapy with periodic glucocorticoid premedication was associated with reduced BMD and increased sBAP levels, which were linked to number of chemotherapy cycles but independent of primary site, chemotherapy regimen, duration, and additive steroid usage

Data from: Incidence of cancer-associated thromboembolism in Japanese gastric and colorectal cancer patients receiving chemotherapy: a single-institutional retrospective cohort analysis (Sapporo CAT study)

Objective: Few data regarding the incidence of cancer-associated thromboembolism (TE) are available for Asian populations. We investigated the incidence of TE (TEi) and its risk factors among gastric and colorectal cancer (GCC) patients who received chemotherapy in a daily practice setting. Design: A retrospective cohort study. Setting: A single institutional study that used data from Sapporo City General Hospital, Japan, on patients treated between January 2008 and May 2015. Participants: Five hundred Japanese GCC patients who started chemotherapy from January 2008 to May 2015. Primary and secondary outcome measures: TE was diagnosed by reviewing all the reports of contrast-enhanced computed tomography (CT) performed during the follow-up period. All types of thrombosis detected by CT or additional imaging tests, such as venous TE, arterial TE, and cerebral infarction, were defined as TE. Medical records of all identified patients were reviewed and potential risk factors for TE including clinicopathological backgrounds were collected. We defined the following patients as ‘active cancer’; patients with unresectable advanced GCC, cancer recurrence during or after completing adjuvant (Adj) chemotherapy, and/or presence of other malignant tumours. Results: Of the 500 patients, 70 patients (14.0%) developed TE during the follow-up period. TEi was 9.2% and 17.3% in gastric and colorectal cancer patients, 18.1% and 3.5% in active and non-active cancer patients, and 24.0% and 12.9% in multiple and single primary, respectively. Multivariate logistic regression analysis showed that colorectal cancer (odds ratio [OR], 2.371; 95% confidence interval [CI], 1.328 to 4.233), active cancer (OR 7.593; 95% CI 2.950 to 19.543), and multiple primary (OR 2.527; 95% CI 1.189 to 5.370) were independently associated with TEi. Conclusion: TEi was 14.0% among Japanese GCC patients received chemotherapy, and was significantly higher among patients with colorectal cancer, active cancer, and multiple primary than among those with gastric cancer, non-active cancer, and single primary, respectively

Incidence of cancer-associated thromboembolism in Japanese gastric and colorectal cancer patients receiving chemotherapy : a single-institutional retrospective cohort analysis (Sapporo CAT study)

Objective Few data regarding the incidence of cancer-associated thromboembolism (TE) are available for Asian populations. We investigated the incidence of TE (TEi) and its risk factors among gastric and colorectal cancer (GCC) patients received chemotherapy in a daily practice setting. Design A retrospective cohort study. Setting A single-institutional study that used data from Sapporo City General Hospital, Japan, on patients treated between January 2008 and May 2015. Participants Five hundred Japanese GCC patients who started chemotherapy from January 2008 to May 2015. Primary and secondary outcome measures TE was diagnosed by reviewing all the reports of contrast-enhanced CT performed during the follow-up period. All types of thrombosis detected by CT or additional imaging tests, such as venous TE, arterial TE and cerebral infarction, were defined as TE. Medical records of all identified patients were reviewed and potential risk factors for TE, including clinicopathological backgrounds, were collected. We defined the following patients as 'active cancer'; patients with unresectable advanced GCC, cancer recurrence during or after completing adjuvant chemotherapy and/or presence of other malignant tumours. Results Of the 500 patients, 70 patients (14.0%) developed TE during the follow-up period. TEi was 9.2% and 17.3% in GCC patients, 18.1% and 3.5% in active and non-active cancer patients, and 24.0% and 12.9% in multiple and single primary, respectively. Multivariate logistic regression analysis showed that colorectal cancer (CRC) (OR 2.371; 95% CI 1.328 to 4.233), active cancer (OR 7.593; 95%CI 2.950 to 19.543) and multiple primary (OR 2.527; 95%CI 1.189 to 5.370) were independently associated with TEi. Conclusion TEi was 14.0% among Japanese GCC patients received chemotherapy, and was significantly higher among patients with CRC, active cancer and multiple primary than among those with gastric cancer, non-active cancer and single primary, respectively. Trial registration number UMIN000018912