Dedifferentiated liposarcoma with chondroblastic osteosarcomatous dedifferentiation

We describe a rare case of dedifferentiated liposarcoma with features resembling chondroblastic osteosarcoma in the dedifferentiated component. The tumor was removed from the left thigh in a 78-year-old male. It consisted of a well-differentiated liposarcoma and an anaplastic component that contained numerous osteoid and cartilaginous tissues surrounded by high-grade spindle cell sarcoma. To our knowledge, only two cases similar to the divergent chondroblastic osteosarcomatous dedifferentiation of this disease have been reported in the literature.     

INTRAOSSEOUS EPIDERMAL CYST OF THE SACRUM. A Case Report

An unusual case of intraosseous epidermal cyst is reported. The patient, a 45-year-old Japanese female, had suffered from lumbago and dysuria for about 15 years. X-ray examinations and CT scan revealed an expanded osteolytic tumor without marginal sclerotic change within the sacrum, which anteriorly invaded the surrounding soft tissues at the S2/3 level. At this time, chordoma was suspected, but epidermal cyst with foreign body granuloma was finally diagnosed from biopsy and surgical specimens.     

Parosteal fasciitis of the clavicle

A rare case of parosteal fasciitis arising from the periosteum of the left clavicle in a 27-year-old woman is reported. Magnetic resonance imaging demonstrated the lesion surrounding the periosteum of the clavicle. The lesion was iso-intense with muscle on T(1)-weighted images and hyperintense on T(2)-weighted images. At surgery, the lesion was discovered to be densely adherent with the periosteum, and excised along with the periosteum. Histopathological examination revealed the proliferation of myofibroblasts in a vague storiform or short fascicular pattern. A large amount of extravasated erythrocytes, and a few lymphocytes were present in the matrix. There were some foci of abundant myxoid materials. Immunohistochemical study showed the cells to be positive for vimentin, alpha-smooth muscle actin and HHF35, but negative for desmin. There was no local recurrence at a 6 months postoperative follow up.     

Immunolocalization of 3β-hydroxysteroid dehydrogenase in human adrenal cortex and in its disorders

Immunohistochemical localization of 3β-hydroxysteroid dehydrogenase/Δ^5→4-isomerase (3β-HSD), which converts Δ⁵-3β-hydroxysteroids to Δ⁴-3-ketosteroids, was performed in the human adrenal gland and in its disorders by employing a specific antibody raised against the enzyme purified from human placenta. Immunoreactivity of 3β-HSD was present in all three cortical zones of the adrenal glands obtained at autopsy, while in surgically removed adrenal glands, immunoreactivity was dominant in the zona fasciculata (ZF), with faint immunoreactivity in the zona glomerulosa (ZG) and the zona reticularis (ZR). Intracortical localization of 3β-HSD in the adrenal glands obtained at autopsy may represent an adrenal adaptation to antemortem stress, with shifting of adrenal pregnenolone- a substrate of 3β-HSD - as well as steroid 17α-hydroxylase from adrenal androgen synthesis to glucocorticoid synthesis. In adrenocortical hyperplasia, marked immunoreactivity was observed in the ZG and outer ZF in adrenal glands with idiopathic hyperaldosteronism and in the ZF and ZR, especially in cortical micronodules, in the adrenal glands associated with Cushing’s disease. In aldosteronoma and Cushing’s adenoma, immunoreactivity of the enzyme was much more intense in large clear tumor cells than in small compact tumor cells. Immunolocalization of 3β-HSD can yield important information toward an understanding of adrenal steroid metabolism in both physiological and pathological processes.     

Frequency thresholds of rat cochlear nerve fibers.

Activities of single cochlear nerve fibers of Wistar rats were recorded extracellularly. Best frequencies (BF) distributed from 0.50 to 62.6 kHz. The audiogram was made as the minimum boundary of the BF threshold distribution. The range of audible frequency was 0.54-63 kHz at 60 dB SPL and 0.15-67 kHz at 100 dB SPL. The lowest trough of the audiogram was 5 dB SPL at 41.2 kHz. There was the second trough of 10 dB SPL at 7.01 kHz leaving a notch between the two troughs. The shapes of the frequency-threshold curves (FTCs) of fibers were evaluated quantitatively and typical FTCs were shown as a function of BF.     

Rapid identification of metallothionein isoforms in liver cytosol fraction by capillary zone electrophoresis using EDTA

Identification of metallothionein (MT) isoforms on capillary zone electrophoresis (CZE) analysis was studied using a linear polyacrylamide-coated capillary at pH 7.4 and EDTA. The CZE system was able to separate standard (purified and commercially available) MT specimens into their isoforms within 10 min. The peaks of MT-1 and MT-2 isoforms disappeared on addition of EDTA to the specimen, and the disappearance was shown to be time-dependent and dose-dependent, although the reason why the peaks decreased is still unclear. A heat-treated cytosol fraction prepared from Zn-injected mouse liver showed many major and minor peaks on CZE analysis. Two major peaks were identified to be MT-1 and MT-2, respectively, by co-injection with the purified MT isoforms. When EDTA was added to the cytosol fraction, the two major peaks, MT-1 and MT-2, and three other minor peaks disappeared time-dependently. Therefore, each MT isoform in the cytosol fraction can be identified by the addition of EDTA, also the peaks are identified by the corresponding migration times of purified MTs. Unknown substances like MT sub-isoforms may also be detected, although this question warrants clarification. From these results, it was concluded that the addition of EDTA is useful for identification of MT isoforms in cytosol fractions on CZE analysis.     

Epidemiologic survey and genetic analysis of endemic hepatitis C virus infection in a Japanese town with a high prevalence of hepatitis B virus carriers

Mass screening for hepatitis C virus antibody was carried out in 875 inhabitants (313 men and 562 women) of a town in Japan with a high rate of hepatitis B virus infection. The overall rate of positivity for anti-HCV was 8.8% (6.4% in men and 10,1% in women). The rate of positivity for hepatitis B virus surface antigen was 11.2%. Five subjects (0.6%) were positive for both markers. HCV-RNA was detected in 65 (88.4%) of 77 individuals who were positive for anti-HCV and in 1 (1.5%) of 60 individuals negative for anti-HCV. The genotype of the HCV genome was determined by PCR analysis using type-specific primers in 60 individuals. HCV type 1b was detected in 51 subjects (85%), type 2a in 3 subjects (5%), and type 2b in 6 subjects (10%). None of the individuals was infected with more than one genotype. The nucleotide sequences of the partial nonstructural 5 region of HCV type 1b genotype obtained from 6 individuals showed at least 92.0% homology in the nucleotide sequence, and 94.8% homology in the amino acid sequence. Homology among these clones was greater than their homology with previously described type 1 b sequences. The findings suggest that there was a specific local origin of HCV infection, although it was not possible to identify any single source of HCV infection. The results also indicate the presence of asymptomatic HCV carriers. © 1995 Wiley-Liss, Inc.     

Epithelioid leiomyosarcoma of the external deep soft tissue

Epithelioid leiomyosarcoma in the external deep soft tissue is extremely rare. Most epithelioid leiomyosarcomas occur in the uterus. We present a case of epithelioid leiomyosarcoma occurring in the muscle of the thigh of a 78-year-old man. Histologically, the tumor predominantly consisted of round or polygonal cells arranged in sheets with a focal spindle cell component. Immunohistochemical analysis revealed that the tumor cells expressed vimentin, alpha-smooth muscle actin, and alpha-sarcomeric actin. The tumor was negative for desmin, S100 protein, glial fibrillary acidic protein, pan-keratin, epithelial membrane antigen, CAM 5.2, HMB-45, leukocyte common antigen, factor VIII-associated antigen, and CD34. Electron microscopically, some tumor cells contained abundant actin-type filaments in their cytoplasm.     

Increased expression of apoptosis-linked gene 2 (ALG2) in the rat brain after temporary focal cerebral ischemia

Calcium is an important mediator of programmed cell death induced by transient cerebral ischemia, and calcium-binding proteins have been implicated in calcium-regulated signal transduction. Apoptosis-linked gene 2 is a calcium-binding protein required for cell death induced by different apoptotic stimuli. By Western blot analysis, we found that apoptosis-linked gene 2 protein was expressed in normal brains, and that expression increased in ischemic brains after 20 or 90 min of transient focal cerebral ischemia. Immunocytochemistry showed increased apoptosis-linked gene 2 protein expression in frontal cortex, a region where neurons underwent ischemic stress but still survived, after 20 or 90 min of focal cerebral ischemia. Apoptosis-linked gene 2 protein was also up-regulated in the ischemic border-zone of parietal cortex 24h after 20 min of focal ischemia, and was remarkably over-expressed in the caudate-putamen and parietal cortex, (where cells are destined to die) 24h after 90 min of ischemia. The expression pattern of apoptosis-linked gene 2 protein was similar to that of deoxyribonucleic acid damage detected by Klenow labeling assay.Our results suggest that apoptosis-linked gene 2 may be involved in the regulation of cell death after transient focal cerebral ischemia.     

Angiosarcoma arising from skeletal haemangiomatosis in an atomic bomb survivor

The authors report a unique case in which an angiosarcoma arose from skeletal haemangiomatosis in a 72 year old man. This patient had a history of atomic bomb irradiation more than 50 years ago. Radiographically, the patient had multiple sclerotic foci of benign haemangiomas in the pelvis, the sacrum, and the left femur. The patient developed a high grade angiosarcoma in the left pubic bone. It is thought that atomic bomb irradiation played an important role in the development of the malignant lesion.