Isoliquiritigenin, from Dalbergia odorifera, up-regulates anti-inflammatory heme oxygenase-1 expression in RAW264.7 macrophages.

OBJECTIVES: Isoliquiritigenin (ISL), one of the major constituents of Dalbergia odorifera T. Chen (Leguminosae), is reported to exert anti-inflammatory effects, but the relevant anti-inflammatory mechanisms are not completely understood. Heme oxygenase-1 (HO-1) has been proven to be involved in the resolution of inflammatory responses. In this study, we investigated whether ISL could induce HO-1 expression in RAW264.7 macrophages, and if so, whether HO-1 could mediate the anti-inflammatory effects of ISL. METHODS: The protein expression of inducible nitric oxide synthase and HO-1 was analyzed by western blot analysis. The production of nitric oxide (NO) and interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) was assayed by Griess and ELISA, respectively. The TNF-alpha and HO-1 mRNA expression was analyzed by northern blot analysis. RESULTS: ISL markedly suppressed LPS-induced NO, IL-1beta, and TNF-alpha production. ISL induced HO-1 expression through the extracellular signal-regulated kinase1/2 pathway in RAW264.7 macrophages. The effects of ISL on LPS-induced NO and TNF-alpha production were reversed by the HO-1 inhibitor, tin protoporphyrin. CONCLUSIONS: ISL is an effective HO-1 inducer capable of inhibiting macrophage-derived inflammation.

Can we predict spontaneous capsule passage after retention? A nationwide study to evaluate the incidence and clinical outcomes of capsule retention.

BACKGROUND AND STUDY AIMS: Although capsule endoscopy has become a central diagnostic tool for small-bowel evaluation, retention of a capsule remains a major concern. This study attempted to investigate the incidence and clinical outcomes of capsule retention, and to determine the factors predictive of spontaneous capsule passage after retention. PATIENTS AND METHODS: Through a nationwide multicenter survey, we retrospectively reviewed the records of 1291 patients who had a capsule endoscopy between February 2002 and July 2006 in Korea. Clinical and procedural characteristics and postprocedural outcomes were analyzed for the cases with capsule retention. RESULTS: Capsule retention occurred in 2.5 % of total cases (32/1291). The major diseases accompanying capsule retention were Crohn's disease, malignant tumors, and tuberculous enterocolitis, in decreasing order. In 11 of the 32 patients (34.4 %), early surgical or endoscopic interventions were instituted for diagnosis or treatment of diseases before retention symptoms developed. The remaining 21 (65.6 %) patients initially received medical treatments. Of these, 10 (31.3 %) ultimately underwent surgical intervention due to the development of symptoms of intestinal obstruction or medical treatment failure. The other 11 (34.4 %) eventually passed the capsule. The presence of a larger lumen diameter (greater than two-thirds of the capsule diameter) at the stricture site was associated with spontaneous passage. CONCLUSIONS: Our large-scale study suggests that retention occurs infrequently during capsule endoscopy. Moreover, a retained capsule might indicate the best intervention for the offending pathology, or it may spontaneously pass in the long run, particularly in patients with less small bowel stricture.

Role of magnetization transfer imaging in bone tumors.

RATIONALE AND OBJECTIVES: The authors evaluated the role of magnetization transfer imaging in differentiation of bone tumors, with special emphasis on cartilaginous tumors. MATERIALS AND METHODS: Fifty-one patients with skeletal tumors or tumor-like lesions who had undergone magnetic resonance (MR) imaging were included. The tumors were divided into three groups according to their gross appearance and the origin of tissue: cyst, cartilaginous tumor, and noncartilaginous solid tumor. A gradient-recalled acquisition in the steady state sequence was used for MR imaging, and examinations were performed both with and without off-resonance magnetization transfer pulses. Magnetization transfer ratios were obtained as an indicator of magnetization transfer effect of the lesions and were compared. Then, the magnetization transfer ratios of all tumors in the cartilaginous tumor group were compared. The magnetization transfer ratios of benign and malignant solid tumors were also compared. RESULTS: The mean magnetization transfer ratio for cartilaginous tumors was 0.31 +/- 0.08 (standard deviation), and that of cysts and noncartilaginous solid tumors was 0.07 +/- 0.03 and 0.40 +/- 0.14, respectively. Comparisons between the three groups showed statistically significant intergroup differences in magnetization transfer ratio (P < .05). In the cartilaginous tumor category, enchondroma and low-grade chondrosarcoma had a lower magnetization transfer effect than chondroblastoma and mesenchymal chondrosarcoma. The mean magnetization transfer ratios of benign (n = 28) and malignant (n = 18) tumors were 0.35 +/- 0.11 and 0.39 +/- 0.15, respectively; there was no statistically significant intergroup difference (P = .14). CONCLUSION: Magnetization transfer imaging could be useful for categorizing bone tumors as cysts, cartilaginous tumors, or noncartilaginous solid tumors.

Hemodialysis-related arthropathy. A prospective MR study with SE and GRE sequences.

PURPOSE: A prospective examination of hemodialysis-related arthropathy by MR imaging with SE and GRE sequences was undertaken to verify whether the low signal intensity on T2-weighted SE images is caused by a paramagnetic susceptibility effect derived from amyloid or from hemosiderin. MATERIAL AND METHODS: Twenty-seven joints (19 hip joints, 6 discovertebral joints of 5 lumbosacral spines and 1 cervical spine, 2 shoulder joints) in 14 patients undergoing long-term hemodialysis (duration 10-22 years, mean 17) were examined with SE T1-weighted, T2-weighted and GRE T2*-weighted sequences. RESULTS: The signal intensity of the intraarticular and periarticular masses of the involved joints was basically isointense to the muscle in all 3 pulse sequences. No significantly low signal area was found on GRE T2*-weighted images. CONCLUSION: The low signal areas in the hemodialysis-related arthropathy on SE T2-weighted images are not caused by a paramagnetic susceptibility effect, but probably by the hypocellular and fibrous nature of amyloid-containing tissues. Therefore the GRE sequence can be helpful for differentiating hemodialysis-related amyloid arthropathy from chronic hemarthrosis or juxta-articular brown tumor.

Intraosseous neurilemmoma of the fibula.

We present a case of intraosseous neurilemmoma of the fibula in a 56-year-old woman. The case showed the typical radiographic appearance except for the presence of spotted calcifications that mimicked a cartilaginous tumor. Enhanced MR images revealed the heterogeneity of the tumor, which consisted of Antoni type A and B tissue.

Ischiopubic insufficiency fractures: MRI appearances.

OBJECTIVE: To evaluate the MRI appearances in insufficiency fractures. DESIGN: A retrospective analysis of spin echo MR images with gadolinium-enhancement was undertaken with the emphasis on the signal change and the shape of the fracture gap and the adjacent bone marrow. PATIENTS: Five elderly women who had ischiopubic insufficiency fractures (pubis, 4; ischium 1) underwent MRI to exclude the possibility of pathologic fractures. RESULTS AND CONCLUSIONS: In no case was contrast enhancement noted at the fracture gap or the adjacent bone marrow, but a cleft-life, elongated bright signal area suggesting "fluid collection" was noted within the fracture gap. Absence of contrast enhancement and "fluid collection" at the fracture gap might suggest non-union of a fracture, which is additional information provided only by MRI.

Hyaline cartilage: in vivo and in vitro assessment with magnetization transfer imaging.

PURPOSE: To elucidate the magnetization transfer (MT) effects of major components of hyaline cartilage. MATERIALS AND METHODS: The authors evaluated the MT effect of type II collagen and chondroitin sulfate phantoms (concentrations of 0.6%, 1.2%, 2.4%, 4.8%, 9.6%, and 19.2%), mass-cultured rat osteosarcoma-derived cells, and normal articular cartilage of the knee. RESULTS: The MT effect of collagen yielded a decrease in signal intensity of 10% (1.2% collagen) to 31% (19.2% collagen); the decrease varied linearly with collagen concentration. Chondroitin sulfate did not have a statistically significant MT effect. Cell pellets showed a decrease in signal intensity of 22%-26%, which was greater than that of 4.8% collagen. Normal articular cartilage of the knees showed a decrease in signal intensity of 38%-48%. CONCLUSION: The major role of collagen in MT contrast of hyaline cartilage was confirmed. In addition, a higher cellular contribution to the MT effect was also demonstrated.

MR findings indicative of hemosiderin in giant-cell tumor of bone: frequency, cause, and diagnostic significance.

OBJECTIVE: We studied the frequency, cause, and diagnostic significance of MR findings indicative of large amounts of hemosiderin in giant-cell tumor of bone. MATERIALS AND METHODS: The clinical, MR, and histologic findings in 16 patients with giant-cell tumors of bone were reviewed. Eight tumors occurred in uncommon locations or in patients who were not in the usual age range; the other eight were more typical. Areas of decreased MR signal intensity considered to be caused by hemosiderin were identified. The number and distribution of RBCs within the tumor were studied histologically, and the presence of hemosiderin was determined on histologic sections made with iron stains. RESULTS: In 10 cases in which MR images showed areas of low signal intensity, large amounts of hemosiderin were noted histologically. The low-signal-intensity areas were nodular, zonal, whorled, or diffuse and occupied at least one fifth of the tumor volume. On histologic examination, many erythrocytes were in direct contact with the tumor cells, and the hemosiderin was seen in both mononuclear and multinuclear tumor cells. CONCLUSION: Hemosiderin is commonly seen on MR images of giant-cell tumors of bone (63%) and is probably related to the extravasated erythrocytes in the tumor and the phagocytic function of the tumor cells. This MR finding supports the diagnosis, even in giant-cell tumors in uncommon locations or in patients who are not in the typical age range.

Epidural dumbbell-shaped chordoma mimicking a neurinoma.

The authors present a case of cervical chordoma which manifested in a 5-year-old boy as a dumbbell-shaped epidural tumor without bone destruction. Both CT and MRI demonstrated tumor features suggesting this diagnosis, which was confirmed by histology.

[Radiological and anatomical investigation of calcific tendinitis of the gluteus maximus tendon].

The radiological findings in four cases of gluteus maximus tendinitis were retrospectively analyzed. All the patients underwent radiographic, CT and MRI examinations. Amorphous or round calcifications were detected on lateral radiographs in three cases, and on CT in all cases. A small cortical erosion was observed in three cases on both radiographs and CT. MRI showed a thickened gluteus maximus tendon, but no other specific features. In the supine position, which is common in routine CT and MRI studies, the calcific deposits appeared to be distributed along the vastus lateralis muscle tendon. To correlate these radiographic observations with the topographic anatomy of the tendon's insertion, we investigated 14 thighs of seven cadavers, and clarified that the tendon's insertion was the main component of the lateral femoral intermuscular septum. Consequently we performed MRI on a volunteer in a prone position who was asked to maintain contraction of the gluteus maximus and quadratus femoris muscles. The images obtained showed clearly that the gluteus maximus tendon was directed dorsally. In conclusion, radiography and CT are the modalities of choice for diagnosis of this entity. Additionally, radiologists should be aware that the gluteus maximus tendons are directed laterally as a main part of the lateral femoral intermuscular septum on routine CT and MRI.

MR appearance of periosteal chondrosarcoma of the foot.

OBJECTIVE: To assess the role of MRI in evaluating periosteal chondrosarcoma in the foot, an anatomically complicated location. MATERIALS AND METHODS: Three cases of surgically and histologically confirmed periosteal chondrosarcomas occurring in the foot (58-year-old woman, 57-year-old woman, and 63-year-old man) were retrospectively reviewed with an emphasis on MR findings. RESULTS: Magnetic resonance successfully delineated the hypovascular nature and lobulating pattern of the lesion suggesting the cartilaginous component, the periosteal location with sparing bone marrow, and the extent of involvement of adjacent structures. These findings were either not seen or less clearly seen on CT in the former two cases. CONCLUSION: In cases of periosteal chondrosarcomas in the foot MRI can play a significant role both in the characterization of the lesion and in planning surgical therapy.

Diagnosis of acute appendicitis in pregnant women: value of sonography.

OBJECTIVE: The diagnosis of acute appendicitis in pregnant women often is difficult to make on the basis of clinical findings, and radiologic examination is limited because of the potentially hazardous effects of radiation. This study was done to assess the value of sonography in the diagnosis of acute appendicitis in pregnant women. SUBJECTS AND METHODS: We obtained sonograms in 45 pregnant women with clinically suspected acute appendicitis. Our sonographic technique included graded-compression scanning. The left lateral decubitus position was used in the third trimester of gestation. The sonographic criterion for the diagnosis of acute appendicitis was visualization of an incompressible appendix with a maximal diameter greater than 7 mm. We correlated the sonographic findings with the surgical findings in 22 cases and with the results of clinical follow-up in 23 cases. RESULTS: Sonography could not be used to make the diagnosis in three (7%) of 45 patients because the size of the gravid uterus prevented use of the graded-compression technique. These three patients were in the third trimester of pregnancy (greater than 35 weeks' gestation). Sonographic findings were used as a basis for diagnosis in 42 cases. Acute appendicitis was diagnosed on the basis of sonograms in 16 patients, and in all but one of these patients, acute appendicitis was confirmed by surgical and pathologic findings. In the 42 cases in which the imaging findings indicated the diagnosis, the overall sensitivity of sonography was 100%, the specificity was 96%, and the accuracy was 98%. CONCLUSION: Our experience suggests that graded-compression sonography is a valuable procedure for detecting acute appendicitis in pregnant women despite technical difficulty in performing it during the third trimester of pregnancy.