Correlation between particle size/domain structure and magnetic properties of highly crystalline Fe3O4 nanoparticles

Highly crystalline single-domain magnetite Fe3O4 nanoparticles (NPs) are important, not only for fundamental understanding of magnetic behaviour, but also for their considerable potential applications in biomedicine and industry. Fe3O4 NPs with sizes of 10–300 nm were systematically investigated to reveal the fundamental relationship between the crystal domain structure and the magnetic properties. The examined Fe3O4 NPs were prepared under well-controlled crystal growth conditions using a large-scale liquid precipitation method. The crystallite size of cube-like NPs estimated from X-ray diffraction pattern increased linearly as the particle size (estimated by transmission electron microscopy) increased from 10 to 64.7 nm, which indicates that the NPs have a single-domain structure. This was further confirmed by the uniform lattice fringes. The critical size of approximately 76 nm was obtained by correlating particle size with both crystallite size and magnetic coercivity; this was reported for the first time in this study. The coercivity of cube-like Fe3O4 NPs increased to a maximum of 190 Oe at the critical size, which suggests strong exchange interactions during spin alignment. Compared with cube-like NPs, sphere-like NPs have lower magnetic coercivity and remanence values, which is caused by the different orientations of their polycrystalline structure.This work was supported by JSPS KAKENHI Grant Number 26709061 and 16K13642. This work was partly supported by the Center for Functional Nano Oxide at Hiroshima University. The authors also gratefully acknowledge the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan for providing scholarships (C. W. K.)

Bilateral Multiple Pulmonary Sclerosing Hemangioma in a Young Male Patient

The patient was a 24-year-old male who visited our University Hospital complaining of chest pain, and chest computed tomography revealed multiple bilateral nodules. The chest pain disappeared almost immediately, but the tumor underwent no changes during the 3 years of follow-up observations. We used a thoracoscope to perform a partial lung resection of a nodule that reached a maximum diameter of 9 mm for the purpose of obtaining a definite diagnosis. From the pathological findings, the patient was diagnosed to have pulmonary sclerosing hemangioma in which circular tumor cells lacking nuclear atypia rose to papillary hyperplasia. The mindbomb homolog-1 positive rate (MIB-1 index) of the tumor cells was less than 1%, and it is believed to have a poor proliferation activity. Pulmonary sclerosing hemangioma is predominantly found in cases of middle-aged female patients and occurs unilaterally. Cases of bilateral multiple forms in young males are extremely rare. Some cases of enlargement, metastasis and relapse have also been reported, so in the future, careful follow-up is required

Inflammatory Pseudotumor of the Lung Identified by 18F-Fluorodeoxyglucose Positron Emission Tomography: A Patient Report

The patient was a 71-year-old man with an abnormal shadow on chest X-ray. Computed tomography (CT) of the chest showed a tumor of 38 mm in size in the upper lobe of the left lung S3. A CT-guided lung biopsy was performed, but no malignancy was observed. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) revealed a high FDG uptake in the tumor: the maximum and mean values of the standard FDG uptake in the early phase were 7.3 and 5.3, respectively, and those in the latter phase, 8.3 and 5.9, respectively. The hilar and mediastinal lymph nodes also showed positive for high FDG uptakes. We strongly suspected lung cancer, and performed a left upper lobectomy by video-assisted thoracic surgery. The pathological diagnosis was an inflammatory pseudotumor of the lung: it is a rare disease but often requires differentiation from lung cancer. Literature has been few on FDG-PET about inflammatory pseudotumor of the lung. Differentiation of the disease from lung cancer was especially difficult in the present patient, because both lymph nodes and the tumor showed high FDG uptakes

Postoperative Radiographic Early-Onset Adjacent Segment Degeneration after Single-Level L4–L5 Posterior Lumbar Interbody Fusion in Patients without Preoperative Severe Sagittal Spinal Imbalance

Study Design Retrospective study. Purpose To investigate the relationship between preoperative total spinal sagittal alignment and the early onset of adjacent segment degeneration (ASD) after single-level posterior lumbar interbody fusion (PLIF) in patients with normal sagittal spinal alignment. Overview of Literature Postoperative early-onset ASD is one of the complications after L4–L5 PLIF, a common surgical procedure for lumbar degenerative disease in patents without severe sagittal imbalance. A better understanding of the preoperative characteristics of total spinal sagittal alignment associated with early-onset ASD could help prevent the condition. Methods The study included 70 consecutive patients diagnosed with lumbar degenerative disease who underwent single-level L4–L5 PLIF between 2011 and 2015. They were divided into two groups based on the radiographic progression of L3–L4 degeneration after 1-year follow-up: the ASD and the non-ASD (NASD) group. The following radiographic parameters were preoperatively and postoperatively measured: sagittal vertebral axis (SVA), thoracic kyphosis (TK), lumbar lordosis, pelvic tilt, and pelvic incidence (PI). Results Eight of the 70 patients (11%) experienced ASD after PLIF (three males and five females; age, 64.4±7.7 years). The NASD group comprised 20 males and 42 females (age, 67.7±9.3 years). Six patients of the ASD group showed decreased L3–L4 disc height, one had L3–L4 local kyphosis, and one showed both changes. Preoperative SVA, PI, and TK were significantly smaller in the ASD group than in the NASD group (p <0.05). Conclusions A preoperative small SVA and TK with small PI were the characteristic alignments for the risk of early-onset ASD in patients without preoperative severe sagittal spinal imbalance undergoing L4–L5 single-level PLIF