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Variation in stacking fault energy with annealing at 1173 K were identified in Czochralski-grown silicon crystals heavily doped with n- or p-type dopant atoms. In n-type crystals, the energy decreased with increasing annealing time. The higher the concentration of dopant atoms, the larger the degree of the decrease. On the other hand, the energy was unchanged during annealing in p-type and nondoped crystals. These results imply that n-type dopant atoms segregate nearby a stacking fault, via their thermal migration, under an electronic interaction leading to a reduction in the stacking fault energy. [ABSTRACT FROM AUTHOR]

The atomic structure of AlN/Al2O3 interface fabricated by pulsed laser deposition is characterized by high-resolution transmission electron microscopy (HRTEM) combined with systematic multi-slice HRTEM image simulations. It is found that the AlN film deposited on a (0001) Al2O3 substrate grows epitaxially with the orientation relationship of (0001)AlN//(0001) Al2O3 and [ $$\bar 1100$$ ]AlN//[ $$11\bar 20$$ ]Al2O3, with an atomically sharp interface. The observed interface showed best correspondence with the rigid structural model that AlN is terminated by Al at the interface, while the Al2O3 substrate is terminated by O. Detailed structural analysis indicates that Al sites at the interface are coordinated by both oxygen and nitrogen in this model, with similar coordination environment in AlN. This favored coordination state at the interface may stabilize the AlN/Al2O3 interface. [ABSTRACT FROM AUTHOR]

An arbitrary number (3×108-1×1010 cm-2) of edge dislocations on (1100) prismatic planes, with the Burgers vector of (a/3)[1120] and with the dislocation lines nearly parallel to [0001], were introduced intentionally in wurtzite ZnO bulk single crystals at elevated temperatures of 923-1073 K, and the optical properties were examined. After the introduction of the dislocations, the intensity of the intrinsic emissions existing in pre-dislocated crystals, i.e., near-band edge emissions and deep level emissions, was almost unchanged, and donor-acceptor pair (DAP) emissions with photon energies of 2.20 and 2.50 eV at temperature of 12 K appeared. The intensity of the DAP emissions increased with increasing the dislocation density. The origin of the DAP emissions was determined as acceptor levels of 0.9 and 1.2 eV depth introduced with the dislocations. [ABSTRACT FROM AUTHOR]

Abstract: Dislocations were introduced in wurtzite zinc oxide single crystals by Vickers indentations on and surfaces at elevated temperatures, and their slip systems were determined by transmission electron microscopy combined with etch pit observations. The observed system for indentations was or (0001) , while that for indentations was . Activation of the slip systems was briefly discussed in terms of the Peierls stress and resolved shear stress acting on the slip systems. [Copyright &y& Elsevier]

Background: Delayed anterior cruciate ligament (ACL) reconstruction often causes residual anterolateral rotatory instability (ALRI) and consequent knee osteoarthritis, warranting the recommendation of early ACL reconstruction within 6 months after injury. Nonetheless, some cases show notable instability, even shortly after injury. The purpose of this study was to identify risk factors for an increase in quantitatively measured pivot shift in patients with ACL-deficient knees within 6 months after injury., Methods: Patients with primary ACL reconstruction within 6 months after injury and quantitative triaxial accelerometer measurements of preoperative pivot shift were included. Descriptive statistics were calculated for 11 independent variables (age, gender, time from injury to surgery, KT-1000, knee extension angle, lateral and medial posterior tibial slope angle, medial and lateral meniscus tears, ramp lesion and Tegner active scale). A single regression analysis was performed on the 11 items and acceleration during the pivot shift, and a multiple regression analysis was performed for items with p value less than 0.1., Results: Overall, 111 patients met the inclusion criteria. Single regression analysis showed that medial posterior tibial slope angle, medial meniscus tear and ramp lesion were significantly correlated with acceleration during the pivot shift ( p  < 0.001, p  = 0.04 and p  = 0.001). Multiple regression analysis identified medial posterior tibial slope angles and ramp lesions as independent factors for increased preoperative pivot shift ( p  = 0.005 and 0.01)., Conclusion: A steep medial posterior tibial slope angle and ramp lesion were independent risk factors for increased quantitatively measured pivot shift in patients with ACL-deficient knees., Level of Evidence: Level IV, case series study., Competing Interests: The authors declare no conflict of interest., (© 2024 The Author(s). Journal of Experimental Orthopaedics published by John Wiley & Sons Ltd on behalf of European Society of Sports Traumatology, Knee Surgery and Arthroscopy.)

Context: Estimated remnant cholesterol (Rem-C) level, a risk factor for cardiovascular disease (CVD), is associated with metabolic dysfunction-associated steatotic liver disease (MASLD) diagnosed via ultrasonography. However, the relationship between accurate serum Rem-C level measurements and histological findings of MASLD remains unclear., Objective: We aimed to elucidate the relationship between accurately measured serum Rem-C levels and histological findings of MASLD., Design: Cross-sectional single-center observational study., Methods: We assessed 222 patients (94 men and 128 women; age 20-80) who were diagnosed with MASLD via liver biopsy with available medical history, physical examination, and biochemical measurement data. Serum ester-type cholesterol and free cholesterol contents in the remnant lipoproteins were measured using an enzymatic method., Results: Serum Rem-C levels were significantly higher in patients with NAFLD activity score (NAS) 5-8, ＞66% steatosis grade, lobular inflammation with ≥5 foci, and many cells/prominent ballooning cells (a contiguous patch of hepatocytes showing prominent ballooning injury) than in patients with NAS 1-4, <33% steatosis grade, lobular inflammation with <2 foci, and few ballooning cells (several scattered balloon cells), respectively. While univariate analysis revealed no significant association between Rem-C levels and advanced fibrosis, a significant association between Rem-C levels and NAS was evident. This relationship remained significant in multivariate analysis adjusted for confounders. Furthermore, in the analysis by sex, these relationships were significant for men but not for women., Conclusion: High serum Rem-C levels were associated with high NAS, but not with fibrosis stage, particularly in men. Controlling serum Rem-C level may improve MASLD activity., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com. See the journal About page for additional terms.)

Purpose: This retrospective study was conducted to investigate the diagnostic accuracy of ultrasound-derived fat fraction (UDFF) for grading hepatic steatosis using liver histology as the reference standard., Methods: Seventy-three patients with liver disease were assessed using UDFF and liver biopsy. Pearson's test and the Bland-Altman plot were used to assess the correlation between UDFF and histological fat content in liver sections. The UDFF cutoff values for histologically proven steatosis grades were determined using the area under the receiver operating characteristic curve (AUROC)., Results: The median age of the patients was 66 (interquartile range 54-74) years, and 33 (45%) were females. The UDFF values showed a stepwise increase with increasing steatosis grade (p < .001) and were strongly correlated with the histological fat content (r = .7736, p < .001). The Bland-Altman plot revealed a mean bias of 2.384% (95% limit of agreement, - 6.582 to 11.351%) between them. Univariate regression analysis revealed no significant predictors of divergence. The AUROCs for distinguishing steatosis grades of ≥ 1, ≥2, and 3 were 0.956 (95% confidence interval [CI], 0.910-1.00), 0.926 (95% CI, 0.860-0.993), and 0.971 (95% CI, 0.929-1.000), respectively. The UDFF cutoff value of > 6% had a sensitivity and specificity of 94.8% and 82.3%, respectively, for diagnosing steatosis grade ≥ 1. There was no association between UDFF and the fibrosis stage., Conclusion: UDFF shows strong agreement with the histological fat content and excellent diagnostic accuracy for grading steatosis. UDFF is a promising tool for detecting and quantifying hepatic steatosis in clinical practice., (© 2024. The Author(s), under exclusive licence to The Japan Society of Ultrasonics in Medicine.)

Backgruound: Poor lifestyle habits may worsen nonalcoholic fatty liver disease (NAFLD), with progression to nonalcoholic steatohepatitis (NASH) and cirrhosis. This study investigated the association between glycemic control status and hepatic histological findings to elucidate the effect of glycemic control on NAFLD., Methods: This observational study included 331 patients diagnosed with NAFLD by liver biopsy. Effects of the glycemic control status on histological findings of NAFLD were evaluated by comparing the following four glycemic status groups defined by the glycosylated hemoglobin (HbA1c) level at the time of NAFLD diagnosis: ≤5.4%, 5.5%-6.4%, 6.5%-7.4%, and ≥7.5%., Results: Compared with the lowest HbA1c group (≤5.4%), the higher HbA1c groups (5.5%-6.4%, 6.5%-7.4%, and ≥7.5%) were associated with advanced liver fibrosis and high NAFLD activity score (NAS). On multivariate analysis, an HbA1c level of 6.5%- 7.4% group was significantly associated with advanced fibrosis compared with the lowest HbA1c group after adjusting for age, sex, hemoglobin, alanine aminotransferase, and creatinine levels. When further controlling for body mass index and uric acid, total cholesterol, and triglyceride levels, the higher HbA1c groups were significantly associated with advanced fibrosis compared with the lowest HbA1c group. On the other hand, compared with the lowest HbA1c group, the higher HbA1c groups were also associated with a high NAS in both multivariate analyses., Conclusion: Glycemic control is associated with NAFLD exacerbation, with even a mild deterioration in glycemic control, especially a HbA1c level of 6.5%-7.4%, contributing to NAFLD progression.

Aim: Advanced fibrosis has a strong influence on the occurrence of liver-related events in patients with metabolic dysfunction-associated steatotic liver disease (MASLD), while diabetes mellitus (DM), which is often complicated by MASLD, is associated with the progression of MASLD. We stratified patients with MASLD according to the severity of liver pathological findings and the presence of DM, aiming to examine whether these indices could be used to accurately assess the risk of developing liver-related events., Methods: A total of 282 patients with liver biopsy-proven MASLD were included. Liver-related events were defined as the occurrence of hepatocellular carcinoma (HCC) and complications of liver cirrhosis, such as ascites, hepatic encephalopathy, Child-Pugh class B and C, as well as treatment-eligible esophageal and gastric varices., Results: Multivariate analysis adjusted for age, sex, body mass index, alanine aminotransferase, creatinine, hemoglobin A1c, smoking habits, dyslipidemia, hypertension, nonalcoholic fatty liver disease activity score (NAS), or fibrosis stage showed that advanced fibrosis with or without DM was a risk factor for liver-related events. The combined effect of DM and advanced fibrosis increased the risk of HCC onset. However, DM alone or in combination with NAS did not affect the development of liver-related events, including the occurrence of HCC and complications of liver cirrhosis., Conclusions: While the assessment of fibrosis in patients with MASLD is important for evaluating the risk of developing liver-related events, combining the assessment of DM may be possible to stratify groups at higher risk of developing HCC., (© 2024 Japan Society of Hepatology.)

Double-stranded RNA-activated protein kinase R (PKR) is highly expressed in colorectal cancer (CRC). However, the role of PKR in CRC remains unclear. The aim of this study was to clarify whether C16 (a PKR inhibitor) exhibits antitumor effects and to identify its target pathway in CRC. We evaluated the effects of C16 on CRC cell lines using the MTS assay. Enrichment analysis was performed to identify the target pathway of C16. The cell cycle was analyzed using flow cytometry. Finally, we used immunohistochemistry to examine human CRC specimens. C16 suppressed the proliferation of CRC cells. Gene Ontology (GO) analysis revealed that the cell cycle-related GO category was substantially enriched in CRC cells treated with C16. C16 treatment resulted in G1 arrest and increased p21 protein and mRNA expression. Moreover, p21 expression was associated with CRC development as observed using immunohistochemical analysis of human CRC tissues. C16 upregulates p21 expression in CRC cells to regulate cell cycle and suppress tumor growth. Thus, PKR inhibitors may serve as a new treatment option for patients with CRC., (© 2024. The Author(s).)

A 79-year-old man received treatment for multiple intrahepatic hepatocellular carcinoma with atezolizumab + bevacizumab. However, he developed lower back pain attributed to spinal metastases upon tumor enlargement; thus, he was admitted to our hospital for a change from atezolizumab + bevacizumab to lenvatinib and radiation therapy for the spinal metastases. On the 11th day after starting lenvatinib treatment, a pulsatile aneurysm appeared in the tumor, detected using abdominal ultrasonography Micro B-flow imaging, which visualized blood flow at a high frame rate; this was diagnosed as a pseudoaneurysm. The patient refused treatment for the pseudoaneurysm; therefore, he was carefully followed up. Fortunately, the pseudoaneurysm disappeared on the 17th day. One month later, the tumor had become completely necrotic. Lenvatinib demonstrated effectiveness in inhibiting angiogenesis in the tumor, as evidenced by a decrease in tumor blood flow. This case report suggests that pseudoaneurysm formation within the tumor occurs early after the administration of lenvatinib; thus, clinicians must be aware of the potential risk of pseudoaneurysm rupture., (© 2024. Japanese Society of Gastroenterology.)