Frozen-section services by telepathology: Experience of 100 cases in the San-in District, Japan

The early experience is reported here of the use of Intra-operative frozen-section service by telepathology using the Integrated Service Digital Network (ISDN), a commercially available system that is being connected between the Department of Pathology of Tottori University and Matsue City Hospital, a distance of 30 km. The transfer rate is currently 64kbit/s. The frozen-section service was conducted for a total of 117 tissue specimens (organs) from 100 patients between August 1993 and May 1995. The average time taken for examination of each specimen of frozen section was 13min, ranging between 2 and 42min. The average number of transmitted Images was 6.2. Six cases necessitated more than 11 transmitted Images to make a diagnosis, while 13 cases could be diagnosed from two images only. Correct and permissible diagnoses were obtained in 109 (93.2%) out of 117 specimens when comparing the telepathology diagnosis with that of direct microscopy. Improper or misdiag-nosis was made for eight cases (specimens), which were misinterpreted as papillary carcinoma in Basedow's disease, adenoma and hyperplasia in two pheochromocytomas, solid-tubular carcinoma in phyilodes tumor, mastopathy in invasive carcinoma, metastatic carcinoma in astrocytoma, follicular lymphoma in reactive hyperplasia, and lymphadenitis in follicular lymphoma. in retrospect, diagnosis of these cases should have been deferred. From the results, it was concluded that the Intraoperatlve frozen-section service by telepathology may be a worthwhile substitute for hospitals with limited accessibility to local pathology service, in spite of pitfalls in some cases. Well prepared, high-quality frozen sections, sufficient verbal communication with surgeons, and a rather conservative attitude on the part of a well-trained pathologist seem to be the essential Ingredients for reaching an accurate decision when using telepathology.     

Histochemical, immunohistochemical and ultrastructural investigations of giant cell tumors of bone

The origin and characteristics of so-called stromal cells (stromal cell) and the osteoclast-like giant cell series of 19 cases of giant cell tumor (G.C.T.) of bone were studied. Immunohistochemically, two interesting cases were found. The stromal cells of one case were alpha-1-antitrypsin positive and those of the other case were alpha-1-antichymotrypsin positive. The histiocytic stromal cells of the latter case seemed to be surely neoplastic since they showed mild to moderate cell atypism. There were foci consisting of fibroblastic cells or osteoid and osteoblasts within the tumor. Those cells in the foci were apparently continuous with the surrounding stromal cells, and they were, therefore, also considered to be neoplastic. These findings strongly indicate that the stromal cells originate from the undifferentiated mesenchymal cells in the bone marrow and may differentiate to osteoblastic, fibroblastic, and histiocytic cells. All cells of these three series were not stained for a high stable form of acid phosphatase (SAPhase). SAPhase activity was demonstrated only in osteoclast-like giant cells and some mononuclear cells, which are recently believed to be non-neoplastic. Therefore, the cell atypia of SAPhase negative stromal cells is considered to have a prognostic value.     

Immunohistological study on malignant fibrous histiocytoma

Malignant fibrous histiocytoma (MFH) shows a mixed proliferation of both fibroblastic and histiocytic cells. Because of their complex morphologic appearances, the nature of truly neoplastic cells in MFH has been controversial. In the present study, immunoperoxidase method (PAP method) was used to examine the intracytoplasmic lysozyme (LY), alpha-1-antitrypsin (A1AT), fibronectin (FN), and polyvalent immunoglobulin (PI) in the fibroblastic and histiocytic cells. Twenty-three cases with MFH were histologically divided into three groups; predominantly fibroblastic type (Group I; 5 cases), mixed fibroblastic and histiocytic type (Group II; 15 cases), and almost pure histiocytic type (Group III; 3 cases). Fibroblastic cells showed a strong positive reaction for LY and A1AT, suggesting the histiocytic nature, while the proliferating cells in Group II were more intensely stained by each of the antibodies than in Groups I and III. Enzyme histochemical examinations on fresh materials were available in 3 cases. These findings suggest that proliferating cells in MFH possess a histiocyte nature.     

Isolation and properties of complement-resistant strains of Escherichia coli K-12.

Several strains that were resistant to the bactericidal action of antibody and complement were isolated from Escherichia coli K-12 W3110/SM by selecting them through the medium containing antiserum and complement. They can be agglutinated by antiserum against the parent strain and showed similar immune adherence reactivity to the parent when sensitized with this antiserum. Few differences were found in the compositions of phospholipids and proteins between both inner and outer membranes of these strains and those of the parent. However, there were fewer short-chain and more long-chain fatty acids in these strains than in the parent. It was also found that unsaturated fatty acide decreased and saturated and cyclopropanoic acids increased in phosphatidylethanolamine and phosphatidylglycerol in both inner and outer membranes of one of these strains when compared with those from the parent. Therefore, the resistance of these strains to the complement-mediated bactericidal action was considered to be due to the rigidity of their membrane structures which might repel the insertion of membrane-attack complement complex C5b-9, although they could fix the earlier complement components up to the step of the formation of C4b,2a,3b complex enzyme.     

Activity of human erythrocyte gangliosides as a receptor to HVJ

Liposomes could bind and fuse efficiently to human erythrocytes in the presence of HVJ when they contained gangliosides isolated from human erythrocytes. Sialosylparagloboside, which has a terminal sequence of NeuAcα2?3Ga1β1?4GlcNac, has a much higher receptor activity to the virus than GD_1a, GD_1b, GT_1b, and GT_1a, all of which contain the terminal sequence of NeuAcα2?3Galβ1?3GalNAc or NeuAcα2?8NeuAcα2?3Galβ1?3GalNAc. The activity of sialosylparagloboside is comparable to that of glycophorin, a major sialoglycoprotein of human erythrocytes, when compared on the basis of the required amount (as sialic acid) of compounds. The high affinity of sialosylparagloboside to the viral HANA protein is also suggested by the finding that it showed high inhibitory activity against HVJ-mediated binding of glycophorin liposomes to erythrocytes. Sialosylparagloboside was also highly susceptible to the viral sialidase, the other biological function of HANA protein.     

Clinical significance of antibodies to nonstructural and core proteins of hepatitis C virus in posttransfusion hepatitis patients during long-term follow-up

The prevalence of hepatitis C antibodies (anti- HCV) among multitransfused patients was studied and compared with predicted values obtained from a post-transfusion hepatitis study and from data on the prevalence of anti-HCV among blood donors. The prevalence of hepatitis B core antibodies (anti-HBc) was also studied to determine the routes of transmission of hepatitis C virus. The patients consisted of 65 dialysis patients (57 on haemodialysis and 8 on continuous ambulatory peritoneal dialysis) and 71 leukemia patients in long-term remission [49 with acute myeloid leukemia (AML) and 22 with acute lymphatic leukemia (ALL)]. The presence of anti-HCV was investigated using a second generation enzyme-linked immunosorbent assay. Reactive samples were confirmed by a second generation recombinant immunoblot assay. Anti-HBc was studied in the 65 dialysis patients and in 40 of the leukemia patients. Three (4.6%) of the 65 dialysis patients and 12 (24.5%) of the 49 AML patients were anti-HCV positive whereas all of the ALL patients were seronegative. The total number of blood units transfused to 134 patients (data on two dialysis patients were not available) was 18,148, out of which 17,575 units had been transfused prior to the initiation of anti- HCV screening of blood donors. On the basis of the anti-HCV prevalence among blood donors and the incidence of post-transfusion hepatitis, the predicted number of seropositive patients was 11 and 18, respectively. Five of the 65 dialysis patients were anti-HBc positive, compared with only one of the 40 leukemia patients. It is concluded that the anti-HCV prevalence among dialysis and leukemia patients is concordant with the risk of receiving contaminated blood products, whereas hepatitis B infection may have other routes of transmission in dialysis patients. © 1993 Wiley-Liss, Inc.     

Stereochemistry of the copolymerization of carbon dioxide with optically active phenylepoxyethane

The stereochemistry of the copolymerization of optically active phenylepoxyethane ( 5 ) with carbon dioxide using a diethylzinc/water system as catalyst was investigated. The optically active copolymer, poly(oxycarbonyloxy-2-phenylethylene) ( 1 ), was hydrolyzed and the oxy-2-phenylethylene unit was isolated in the form of 1,2-bis(trimethylsilyloxy)-1-phenylethane ( 3 ). The determination of the optical activity of this ether led to the conclusion that the ring opening of 5 takes place predominantly at the methineoxygen linkage accompanying an inversion in the copolymerization. This fact is in sharp contrast with the stereochemistry of the copolymerization of carbon dioxide with 1,2-epoxypropane in which the ring opening takes place at the methylene-oxygen linkage.