Toshiro Takimoto

Anatomic Properties of Myocardial Bridge Predisposing to Myocardial Infarction

Background— A myocardial bridge (MB) that partially covers the course of the left anterior descending coronary artery (LAD) sometimes causes myocardial ischemia, primarily because of hemodynamic deterioration, but without atherosclerosis. However, the mechanism of occurrence of myocardial infarction (MI) as a result of an MB in patients with spontaneously developing atherosclerosis is unclear. Methods and Results— One hundred consecutive autopsied MI hearts either with MBs [MI(+)MB(+) group; n=46] or without MBs (n=54) were obtained, as were 200 normal hearts, 100 with MBs [MI(−)MB(+) group] and 100 without MBs. By microscopy on LADs that were consecutively cross-sectioned at 5-mm intervals, the extent and distribution of LAD atherosclerosis were investigated histomorphometrically in conjunction with the anatomic properties of the MB, such as its thickness, length, and location and the MB muscle index (MB thickness multiplied by MB length), according to MI and MB status. In the MI(+)MB(+) group, the MB showed a significantly greater thickness and greater MB muscle index (P<0.05) than in the MI(−)MB(+) group. The intima-media ratio (intimal area/medial area) within 1.0 cm of the left coronary ostium was also greater (P<0.05) in the MI(+)MB(+) group than in the other groups. In addition, in the MI(+)MB(+) group, the location of the segment that exhibited the greatest intima-media ratio in the LAD proximal to the MB correlated significantly (P<0.001) with the location of the MB entrance, and furthermore, atherosclerosis progression in the LAD proximal to the MB was largest at 2.0 cm from the MB entrance. Conclusions— In the proximal LAD with an MB, MB muscle index is associated with a shift of coronary disease more proximally, an effect that may increase the risk of MI.

Multilocular cystic renal cell carcinoma: a clinicopathological, immuno- and lectin histochemical study of nine cases

Multilocular cystic renal cell carcinoma (MCRCC) is an uncommon variant of renal neoplasm and its histogenesis is unclear. The aim of this study was to use immuno‐ and lectin histochemistry to delineate histochemical patterns which might indicate the histogenetic origin of MCRCC from a particular part or parts of the nephron. We present our experience with nine cases of MCRCC. Fifteen cases of renal cell carcinoma with cystic degeneration (RCC‐CD) were selected for comparison with MCRCC. We carried out clinicopathological and immunohistochemical examinations of the MCRCC cases. Clinically, the prognosis of the patients was quite good, in that all nine patients are alive and without recurrence at the time of this report. The MCRCCs reacted strongly in a higher proportion of cases with the distal nephron markers, such as peanut agglutinin (PNA, 88.9%) and MUC1–core antibody (MUC1, 100%), but none reacted preferentially with proximal nephron markers such as vimentin, Leu M1 and Lotus tetragonolobus (LTA). The RCC‐CD tumours reacted with vimentin (40%), Leu M1 (66.7%) and LTA (86.7%). Except for two cases, the RCC‐CD tumours did not react with PNA or MUC1 core antibody. These results illustrate the different patterns of expression of MCRCC and RCC‐CD and suggest that MCRCC originates from the distal nephron. Therefore, MCRCC should be differentiated from other types of renal cell carcinoma on the basis of the histogenesis of the tumour and the clinicopathological findings.

Focal Segmental Glomerular Hyalinosis and/or Sclerosis in Rats with Congenital Unilateral Hydronephrosis

Focal segmental glomerular hyalinosis and/or sclerosis (FSHS) was observed in five Wistar‐Imamichi rats with congenital unilateral hydronephrosis (CUH rats). Marked proteinuria (164.9+138.4mg/day) was observed in the CUH rats. Immunoperoxidase staining for IgM, C3 and IgG was positive in the glomerull, showing in a focal, segmental pattern that corresponded to the areas of FSHS seen by light microscopy. These glomerular findings were extremely similar to those of human focal glomerular sclerosis (FGS). FSHS was found to be common to both the hydronephrotic kidney and the contralateral kidney without hydronephrosis. Morphometry revealed that the glomerular area of the juxtamedullary glomeruli was greater than that of superficial glomeruli in control rats (11,037 μm2 vs. 6,847 μm2). On the other hand, glomerular hypertrophy was observed in non‐sclerotic glomeruli of CUH rats (superficial glomeruli; 12,477–16,123 μm2, juxtamedullary glomeruli; 14,635–18,418 μm2). Also, a decreased in the number of glomeruli within the range 1.8‐4.1 per unit area (1 mm2) was seen in CUH rats compared with control rats (mean 4.4). These results suggest that the increased rate of development of FSHS is based on hyperfiltration in the remaining functional nephrons. Acta Pathol Jpn 41: 653–660, 1991.

Technique standard de coupes histologiques sur échantillons de RME

RésuméDans la présente étude, nous comparons et confrontons l’image reconstituée à partir de coupes histologiques sériées et l’image obtenue par l’examen au microscope après coloration au bleu alcian-hématoxyline (méthode BAH), ceci en tant que méthode d’évaluation de la nature et de l’extension des cellules tumorales. La performance diagnostique de l’endoscopie dans le diagnostic des mini et petites lésions s’eat avérée correcte dans 16 foyers sur 28, alors que le diagnostic par BAH était concordant pour toutes les lésions grâce aux techniques d’agrandissement et de coloration qui facilitent l’identification des traits caractéristiques des carcinomes gastriques plats et déprimés; à savoir la marge effilée à terminaison abrupte (Type Cliff, différences Niveu), le bord érodé de la berge des plis (type Rias coat) à la fois sur des lésions plates et déprimées. En cas de dysplasie. l’erreur concernant l’extension de la lésion déterminée par le pouvoir d’amplification du microscope à dissection et l’image reconstruite à partir de coupes sériées, était supérieure ou égale à 1 mm. Selon ces observations, l’évaluation histologique de l’extension et de la diffusion intra-murale des lésions de dysplasie ou de carcinome intra-muqueux ou à envahissement limité, réséquées par RME (Résection muqueuse endoscopique) bénéficient de la méthode BAH. En revanche la méthode BAH ne permet pas l’évaluation correcte de la profondeur de l’envahissement carcinomateux: ceci revient à dire que le microscope à dissection ou l’observation de coupes sériées après BAH ne contribuent pas au diagnostic différenciel entre dysplasie et carcinome modérément invasif. Sur des échantillons gastriques réséqués par RME, la méthode BAH est efficace dans le diagnostic de la nature de la lésion et celui de l’extension intra-muqueuse du processus tumoral.SummaryIn this paper, we compare and contrast the image reconstructed from serial sections and the image obtained through dissecting microscopy using Alcian blue and Hematoxylin staining method (BAH method), as a means to diagnose the quality and spread of tumor cells. The qualitative diagnosis of endoscopy to the minute and small lesions was correct in 16 out of 28 foci, however the BAH diagnosis was correct in all lesions because the magnified and stained method made it easy to detect the characteristics of flat and depressed gastric carcinoma; that is, the tapering, abrupt ending (Cliff type, Niveu Differences), eroded edge of the fold (Rias coat type) in the margin of the flat or depressed lesions. In the dysplasia, the error between the extension of lesion determined by dissecting microscopy and the reconstructed image of serial sections was within approximately 1 mm or less. These findings were indicated that the routine sections for histology including the extension of the intramucosal spreading in the dysplasia or intramucosal and scanty invasive carcinoma taken by EMR (Endoscopic Mucosal Resection) could be done by BAH method. On the other hand, the depth of carcinomatous invasion could not be diagnosed by BAH method effectively; in other words, the differential diagnosis between the dysplasia and the scanty invasive carcinoma in macroscopy and BAH observation was undeterminated. In EMR specimens of the stomach, BAH method is effective in the evaluation of the qualitative diagnosis and in the diagnosis of extension of intramucosal spreading tumor.