Observation and quantitative analysis of dislocations in steel using electron channeling contrast imaging method with precise control of electron beam incident direction.

Electron channeling contrast imaging (ECCI) was applied by precisely controlling the primary electron beam incident direction of the crystal plane in scanning electron microscope (SEM), and the dislocation contrast in steel materials was investigated in detail via SEM/ECCI. The dislocation contrast was observed near a channeling condition, where the incident electron beam direction of the crystal plane varied, and the backscattered electron intensity reached a local minimum. Comparing the dislocation contrasts in the visualized electron channeling contrast (ECC) images and transmission electron microscope (TEM) images, the positions of all dislocation lines were coincident. During the SEM/ECCI observation, the dislocation contrast varied depending on the incident electron beam direction of the crystal plane and accelerating voltages, and optimal conditions existed. When the diffraction condition g and the Burgers vector b of dislocation satisfied the condition g⸱b = 0, the screw dislocation contrast in the ECC image disappeared. An edge dislocation line was wider than a screw dislocation line. Thus, the SEM/ECCI method can be used for dislocation characterization and the strain field evaluation around dislocation, like the TEM method. The depth information of SEM/ECCI, where the channeling condition is strictly satisfied, can be obtained from dislocation contrast deeper than 5ξg, typically used for depth of SEM/ECCI.

The Detection of Urinary Podocytes from Drug-Induced Glomerular Thrombotic Microangiopathy in Advanced Cancer Patients.

BACKGROUND: Focusing on glomerular thrombotic microangiopathy (TMA), we detected urinary podocytes to evaluate podocyte damage following glomerular endothelial cell injury. METHODS: We analyzed the relationship between urinary podocytes as biomarkers for podocyte injuries and clinical manifestations in five patients of anti-cancer-drug-induced glomerular TMA. RESULTS: Cancer in all five patients was advanced, including 4 cases of renal cell carcinoma treated with tyrosine kinase inhibitor, and one with intrahepatic bile duct carcinoma treated with gemcitabine. Urinary podocytes were detected in 2 cases that rapidly developed acute kidney injury (AKI) and nephrotic syndrome, while they were not detected in 3 cases of slowly progressive chronic renal failure. One case with AKI, presenting sequential manifestations of urinary podocytes, showed the decrease and disappearance of urinary podocytes in accordance with the cessation of the anti-cancer drug, followed by improvement in renal function and in clinical symptoms such as hypertension. CONCLUSIONS: These findings indicate that severe endothelial cell dysfunction during the acute phase of glomerular TMA leads to podocyte loss.

Plasma free metanephrines in the diagnosis of pheochromocytoma: diagnostic accuracy and strategies for Japanese patients.

Measuring the levels of the plasma free metanephrines (PFMs) represents a recently developed and promising test for the diagnosis of pheochromocytoma in the United States and Europe. As this test has not yet been evaluated in Japan, it is necessary to evaluate the diagnostic efficacy of measuring the levels of PFMs compared with the standard measurement of the urinary excretion of metanephrines (uMNs) whose reliability is well established to detect of pheochromocytoma. A total of 101 Japanese subjects clinically suspected of having pheochromocytoma in were included in this study. Subsequently, we prospectively measured the PFMs levels in all patients, compared with those of biochemical markers of the catecholamine secretion and metabolisms in the plasma and urine. All subjects with adrenal tumors underwent tumor excision. Data were available for 84 of the 101 patients, 47 of whom had histopathologically proven pheochromocytoma and 37 were finally diagnosed with non-pheochromocytoma. The results of comparisons in the accuracy of measurement for diagnosis of pheochromocytoma between PFMs and the urinary excretion of metanephrines (uMNs) were 0.980 VS 0.951 for AUC of receiver operatorating characteristic (ROC) curve, 0.957 VS 0.894 for sensitivity, and 0.973 VS 0.946 for specificity, respectively. Although the differences were small, the results of our study definitely demonstrated that measurement of PFMs was not inferior to standard urinary metanephrines (uMNs) measurement, which is established to be the most reliable biochemical method to detect pheochromocytoma. This study clearly shows measuring the PFMs levels to be a reliable and efficient method for diagnosing pheochromocytoma in Japanese patients, as demonstrated in previous reports.