Pediatric myositis ossificans mimicking osteosarcoma

Myositis ossificans (MO) is a rare benign cause of heterotopic bone formation in soft tissue that most commonly affects young adults, typically following trauma. We report the case of an 11‐year‐old girl who developed MO mimicking osteosarcoma in her right shoulder. Plain radiography and computed tomography showed poorly defined flocculated densities in the soft tissue and a periosteal reaction along the proximal humerus. On magnetic resonance imaging, the mass displayed an ill‐defined margin and inhomogeneous signal change. Histologically, the mass had a pseudosarcomatous appearance. Based on these findings, the patient was initially misdiagnosed with osteosarcoma at another hospital. The diagnosis was difficult because the patient was 11 years old and had no trauma history, with atypical radiographic changes and a predilection for the site of origin for osteosarcomas. We finally made the correct diagnosis of MO by carefully reviewing and reflecting on the pathological differences between stages.     

Repeated piezoelectric lithotripsy for gallstones with and without ursodeoxycholic acid dissolution: A multicenter study

The use of bile acid dissolution therapy in extracorporeal shockwave lithotripsy of gallstones, remains controversial. Our study examined whether chemolitholysis after sufficient disintegration enhanced stone clearance within 6 months of the first lithotripsy. A total of 143 patients who developed one to three radiolucent stones measuring⪯30 mm in diameter were randomly separated into two treatment groups: 47% were given lithotripsy alone, and 53% lithotripsy plus ursodeoxycholic acid (UDCA). Repeated piezoelectric lithotripsy was given, with no limit on the total number of treatment sessions, to pulverize or disintegrate stones into fragments<3 mm. Stones were disintegrated in 97% of all patients, and the fragments were ⪯2 mm in 50% of these patients. According to an intention-to-treat analysis, 52% in the lithotripsy alone group and 58% in the UDCA group were free of stones 6 months after the first lithotripsy (P=0.61). Of the patients with fragments⪯2 mm, 71% in the former and 86% in the latter group were free of stones 6 months after the first lithotripsy, with no significant difference between the groups. Biliary pain occurred in 25% of all patients, including 3 with acute cholecystitis. We concluded that the sufficient disintegration of gallstones achieved with repeated lithotripsy enhanced the early clearance of fragments, regardless of whether chemolitholysis was employed.     

Dendritic cell SIRPα regulates homeostasis of dendritic cells in lymphoid organs

Signal regulatory protein α (SIRPα), an immunoglobulin superfamily protein that is expressed predominantly in myeloid lineage cells such as dendritic cells (DCs) or macrophages, mediates cell–cell signaling. In the immune system, SIRPα is thought to be important for homeostasis of DCs, but it remains unclear whether SIRPα intrinsic to DCs is indeed indispensable for such functional role. Thus, we here generated the mice, in which SIRPα was specifically ablated in CD11c⁺ DCs (Sirpa^ΔDC). Sirpa^ΔDC mice manifested a marked reduction of CD4⁺ CD8α^– conventional DCs (cDCs) in the secondary lymphoid organs, as well as of Langerhans cells in the epidermis. Such reduction of cDCs in Sirpa^ΔDC mice was comparable to that apparent with the mice, in which SIRPα was systemically ablated. Expression of SIRPα in DCs was well correlated with that of either endothelial cell‐selective adhesion molecule (ESAM) or Epstein–Barr virus‐induced molecule 2 (EBI2), both of which were also implicated in the regulation of DC homeostasis. Indeed, ESAM⁺ or EBI2⁺ cDCs were markedly reduced in the spleen of Sirpa^ΔDC mice. Thus, our results suggest that SIRPα intrinsic to CD11c⁺ DCs is essential for homeostasis of cDCs in the secondary lymphoid organs and skin.     

Metachronous solitary mediastinal lymph node metastases of hepatocellular carcinoma treated by video‐assisted thoracic surgery twice: Report of a case

Solitary mediastinal lymph node metastasis of hepatocellular carcinoma (HCC) is rare. We report a case of metachronically solitary mediastinal metastases of HCC treated by video‐assisted thoracic surgery (VATS) twice. A 66‐year‐old man underwent repeated laparoscopic radiofrequency ablation or trans‐arterial catheter chemo‐embolization against HCC for more than 10 years. The level of alpha fetoprotein protein was elevated, and radiological modalities including FDG‐PET revealed solitary mediastinal tumor metachronically. VATS was performed bilaterally twice. The postoperative course was uneventful and there had no recurrence of extra‐hepatic metastases and tumor markers are within normal limits at 18 months after second VATS. VATS is a minimally invasive and useful procedure for solitary mediastinal lymph node metastasis of HCC. If primary HCC was controlled and lymph node metastasis was solitary, mediastinum lymphadenectomy using VATS might give good short and long term results.     

Small dense LDL phenotype is associated with postprandial increases of large VLDL and remnant-like particles in patients with acute myocardial infarction

BACKGROUND: The small dense low-density lipoprotein (LDL) phenotype (pattern B), high concentrations of remnant-like particles (RLPs), and postprandial lipemia are newly recognized risk factors for coronary heart disease (CHD). However, the associations of these lipoprotein abnormalities remain unclear. The aim of this study was to investigate the relationships among LDL phenotype, very-low-density lipoprotein (VLDL) subclasses, and postprandial lipoprotein metabolism in CHD patients. METHOD: We performed an oral fat tolerance test in 32 patients with acute myocardial infarction and compared the following parameters between patients characterized by either large buoyant LDL (pattern A) versus pattern B: lipids and apolipoproteins (apo) in the plasma and Svedberg flotation rates (Sf) >400 (chylomicron), Sf 60-400 (large VLDL), and Sf 20-60 (small VLDL) fractions. RESULT: Fasting levels of triglyceride, RLP-cholesterol and RLP-triglyceride were slightly higher in the pattern B patients. Postprandial increases of RLP-cholesterol and the cholesterol and triglyceride of large VLDL fractions were significantly greater in the pattern B patients. The areas under the curves of cholesterol, triglyceride, and apo-B in large VLDL fractions were significantly higher in pattern B, while those in small VLDL were not. RLP-cholesterol and RLP-triglyceride in fasting and fed states correlated very highly with the corresponding cholesterol and triglyceride concentrations in large VLDL fractions. CONCLUSION: These results suggest that postprandial increase of large VLDL fractions and RLPs contribute to the formation of small dense LDL in CHD patients.     

Hepatic collagen synthesis in patients with alcoholic and nonalcoholic liver disease

To examine the synthesis of hepatic collagen in patients with alcoholic and nonalcoholic liver disease, liver biopsy specimens were incubated in vitro with¹⁴C-proline, and the radioactivity of the newly synthesized protein-bound¹⁴C-hydroxyproline was measured. Mean hepatic collagen synthesis was 0.82±0.19 pmole of¹⁴C-hydroxyproline/g liver/2 h in control subjects without histological liver fibrosis. Hepatic collagen synthesis was increased in patients with alcoholic and nonalcoholic liver diseases, especially in those with alcoholic fibrosis, alcoholic cirrhosis and chronic active hepatitis. The raised collagen synthesis in alcoholic liver disease rapidly decreased after withdrawal of alcohol. When alcoholic liver disease were compared with nonalcoholic liver disease, there was no significant difference in hepatic collagen synthesis. This work was supported in part by a grant-in-aid for EncourageMent of Young Scientists (No.57770489) from the Ministry of Education, Science and Culture of Japan.     

Correction to: Quantitative evaluation of anti-resorptive agent-related osteonecrosis of the jaw using bone single photon emission computed tomography in clinical settings: relationship between clinical stage and imaging

Annals of Nuclear Medicine -     

Regional differences in mucosal hemodynamics in experimental colonic injury in rats

In rat colon damaged by 10% acetic acid and by dinitrochlorobenzene, we test the following hypotheses: (1) mucosal hemodynamic changes are significantly different at the ulcer base, the ulcer margin, and the inflamed non-ulcer-bearing mucosa; and (2) these mucosal hemodynamic changes also vary with time after induction of the colonic injury. Mucosal hemodynamic changes were documented by reflectance spectrophotometry, and variations in gross mucosal morphology were confirmed by hematoxylin and eosin histologic sections. Results revealed that in the acute stage, the ulcer base, which was covered by necrotic debris, showed ischemia without congestion. The ulcer margin at the edge of the ulcer base showed ischemia with congestion. The nonulcerated mucosa, which appeared erythematous, showed increased perfusion. In the convalescent stage, all the altered perfusion patterns returned to normal. These observations offer plausible explanations for the variability in colonic perfusion observed in experimentally damaged colons.