Histochemical and immunohistochemical analyses of the myocardial scar fallowing acute myocardial infarction

BACKGROUND/AIM

The heart has traditionally been considered as a static organ without capacity of regeneration after trauma. Currently, the more and more often asked question is whether the heart has any intrinsic capacities to regenerate myocytes after myocardial infarction. The aim of this study was to present the existence of the preserved muscle fibers in the myocardial scar following myocardial infarction as well as the presence of numerous cells of various size and form that differently reacted to the used immunohistochemical antibodies.

METHODS

Histological, histochemical and immunohistochemical analyses of myocardial sections taken from 177 patients who had died of acute myocardial infarction and had the myocardial scar following myocardial infarction, were carried out. More sections taken both from the site of acute infarction and scar were examined by the following methods: hematoxylin-eosin (HE), periodic acid schiff (PAS), PAS-diastasis, Masson trichrom, Malory, van Gieson, vimentin, desmin, myosin, myoglobin, alpha actin, smoth muscle actin (SMA), p53, leukocyte common antigen (LCA), proliferating cell nuclear antigen (PCNA), Ki-67, actin HHF35, CD34, CD31, CD45, CD45Ro, CD8, CD20.

RESULTS

In all sections taken from the scar region, larger or smaller islets of the preserved muscle fibers with the signs of hypertrophy were found. In the scar, a large number of cells of various size and form: spindle, oval, elongated with abundant cytoplasm, small with one nucleus and cells with scanty cytoplasm, were found. The present cells differently reacted to histochemical and immunohistochemical methods. Large oval cells showed negative reaction to lymphocytic and leukocytic markers, and positive to alpha actin, actin HHF35, Ki-67, myosin, myoglobin and desmin. Elongated cells were also positive to those markers. Small mononuclear cells showed positive reaction to lymphocytic markers. Endothelial and smooth muscle cells in the blood vessel walls were positive to CD34 and CD31, and smooth muscle cells to SMA. Oval and elongated cells were positive to PCNA and Ki-67. The preserved muscle fibers in the scar were positive to myosin, myoglobin and desmin as well as elongated and oval cells. Other cells were negative to these markers.

CONCLUSION

Our findings speak that myocardial regeneration is maybe possible and develops in human ischemic heart damages and that the myocardium is not a static organ without capacity of cell regeneration.

[Impact of heart myxoma localization upon its clinical course and outcome]

INTRODUCTION

Primary heart tumors are very rare. They can be benign and malignant. Benign ones make about two thirds of all heart tumors. However, they are benign only by their biologic characteristics, but potentially malignant by their localization. About three forths of benign tumors are myxomas. Their growth is usually slow and they can be for a long time silent, particularly if they do not compromise vital functional parts of the heart. Myxomas grow in the atria, mostly in the left one and very rarely in the ventricles.

CASE REPORT

We presented two patients with myxomas in the left, and, in the right atrium which are representative samples of the most common localization of heart myxoma considering previous knowledge of these tumors. Analysis of the clinical course in the two presented patients with characteristic localizations showed general characteristics of the clinical course of heart myxoma. The patients did not have characteristic symptoms for a rather long period of time and the findings obtained by standard examinations did not raise suspicion of heart tumor. Pulmonary symptomatology in one patient and cardial in the other, when tumor had already occupied almost the entire atrium, suggested necessity of cardiologic examination. Indication for operation was in both patients confirmed after performed echocardiography, computed tomography of the thorax and angiography with ventriculography. The size of the removed atrial tumors and their localization explained some of the patients' troubles, but it was also amazing that they had not caused more serious problems. Operation as the only method of treatment was successful in both female patients and its effect was permanent. At annual controls neither recurrence of the tumor nor troubles possibly associated with it were observed.

CONCLUSION

Patients with heart myxoma usually pass through asymptomatic or oligosymptomatic phase, but when troubles become manifested, they do not much differ from those due to other causes. For this reason this tumor can be diagnosed just when complications caused by its localization and growth develop. Modern cardiologic diagnostics, primarily preventive non-invasive echocardiography, enables timely diagnosis and removal of the tumor because only then it may take a name benign tumor.

[Frequency of metastatic tumors in the heart]

INTRODUCTION

Secondary or metastatic tumors in the heart occur more frequently than primary ones, and, according to the published series, their frequency found in autopsic material ranges from 1.6% to 20.6%. Metastatic tumors in the heart are rarely clinically symptomatic, and, therefore, they are rarely diagnosed within the lifetime. They are mostly diagnosed at autopsy. The aim of this study was to analyze the frequency of metastatic tumors of the heart, their primary localization, as well as the localization of the metastases found in the autopsic material within the period 1972-2004.

METHODS

During the autopsy of the patients died of metastatic tumors, we microscopically and macroscopically analyzed all the organs and tissues to determine the metastases of primary tumors in other organs, especially in the heart and pericardium.

RESULTS

Within the period from 1972-2004, 11 403 autopsies were performed. In 2 928 (25.6%) out of 11 403 autopsies, the presence of malignant tumor was diagnosed, and in 79 (2.7%) of these cases, metastasis of the heart was found out. Only in 5 of the cases, the presence of metastasis in the heart was diagnosed during the lifetime. The most frequent metastases in the heart were caused by pulmonary carcinoma (18 cases), leukemia and malignant lymphoma (8 cases, each), then pancreatic and breast carcinoma, while the metastases of other carcinomas were rather rare. In 40 (60.76%) cases, the metastasis was localized in the myocardium, but more often in the left ventricle, in 24 (30.38%) cases in the pericardium, in 4 cases in the epicardium and in the 3 of them in the mitral and tricuspid valve. Only in one case of renal carcionoma, metastasis was found in the right atrium and it occurred by spreading (dissemination) through the lumen of the inferior vena cava.

CONCLUSION

Metastatic tumors of the heart are rather rare, and rarely clinically symptomatic, and, thus, rarely diagnosed during life. The methods of choice for the diagnosis of the metastasis in the heart are echocardiography, computerized tomography, magnetic resonance imaging, cytological analysis of the pericardial effusion and biopsy. The treatment includes surgery, chemotherapy and radiotherapy.

[Importance of inflammation in arteriosclerotic plaque destabilization and rupture]

INTRODUCTION

Although Rudolf Virchow considered arteriosclerosis an inflammatory disease in his book Cellular Pathology publisched in 1858, the opinion that it was a degenerative arterial disease as a civilization disease prevailed. Nowadays, a great attention has been paid to the inflammatory process in the patogenesis of arteriosclerosis and particularly in the destabilization and rupture of plaque.

AIM

To find out whether T and B lymphocytes, lipid macrophages, vascular smooth muscle and mast cells as well as plaque destabilization and rupture are present in ruptured arteriosclerotic plaque in the coronary arteries.

METHODS

Histochemical and immunochemical analyses of 68 ruptured arteriosclerotic plaques from the coronary arteries were performed. Microscopic examination revealed the presence of inflammation elements in all of them. The following histochemical and immunochemical methods were applied: Masson's trichrome, actins, vimentin, CD3, CD43, CD68, CD20, CD45 and chlorine acetyl esterase. The control group included 10 arteriosclerotic plaques from the coronary arteries with fibrous cap, but without inflammation cells.

RESULTS

Rupture of the arteriosclerotic plaque fibrous cap, with thinned and torn collagen fibers, was found in all of the 68 arteriosclerotic plaques. In 57 out of 68 analysed plaques, the increased number of T-lymphocytes, lipid macrophages, vascular smooth muscle and mast cells particularly on the plaque rupture site were found. In the remaining 11 specimens, mast cells were present in a somewhat smaller number. In the control group with the stable plaque, inflammation cells were not observed.

CONCLUSION

Our results pointed out that the inflammatory elements, which might exert an effect upon the arteriosclerotic plaque destabilization, and rupture had been present in the ruptured arteriosclerotic plaque.

[Morphological changes in aorto-coronary vein graft--the analysis of autopsy and biopsy material]

BACKGROUND

Patients with implanted aortic coronary grafts have different survival time, which raises the question why the efficacy of graft implants is so poor. The aim of this study was to present the results of the analysis of morphological changes in the vein grafts taken after the death of patients who died after surgery in different time intervals, as well to present the analysis of the grafts obtained after surgical reintervention.

METHODS

The total number of 656 grafts of 308 dead patients was analyzed, as well as 76 grafts from 40 patients who underwent surgical reintervention. According to the duration of the graft since surgical intervention until death, all the analyzed changes were divided into two groups: a) early changes and complications, and b) late changes and complications in aorto-coronary vein grafts.

RESULTS

After the autopsy, 518 vein grafts from the first group were evaluated histopathologically. Changes were found in the form of small or large areas with peeled endothelium in 266 grafts, with the insudation of fibrin and thrombocytes in such places, subendothelial edema, and occlusive thrombosis of the graft lumen. Significant stenosis, which occurred distally from the anastomoses, was present in 118 grafts without changes in the walls of the graft, and there was significant narrowing of the graft lumen in 134 vein grafts due to intimal hyperplasia. In the second group, 138 grafts were histopathologically analyzed after autopsy. Significant hyperplasia was present in 117 grafts with the migration of smooth muscle cells from media into intima, and in 21 grafts there were atheromatous plaques. In 120 veins analyzed before the graft implantation, the lesion or the lack of endothelium was found, as well as the penetration of fibrin and blood elements and intimal hyperplasia. In 46 veins analyzed before the graft implantation, significant intimal hyperplasia with the elevated number of smooth muscle cells was found.

CONCLUSION

The most frequent lesions in the grafts were the lesions of the endothelium, which caused thrombosis formation and lumen occlusion. Intimal hyperplasia in patients with longer survival time occurred due to the migration of smooth muscle cells from the media, or due to the formation of atherosclerotic plaques, which caused graft lumen stenosis or thrombosis.

[Osteoid osteoma--ten-years' experience in therapy]

AIM

To review ten-years experience in diagnostics and operative treatment of osteoid osteoma.

METHODS

A total of 15 patients were retrospectively analyzed in this study. Clinical diagnosis was based on medical check-up, aspirin test, and conventional laboratory and radiographic examinations. CAT scan radionuclide bone scan, and magnetic resonance were performed in certain cases. All the patients were operatively treated by local resection of the tumor-infested bone. The resected part of the bone was intraoperatively checked by X-ray. The aim of this examination was to verify nidus in the resected bone. Afterwards, the resected bone with nidus was histologically analyzed.

RESULTS

Osteoid osteoma was histologically verified in 86.6% of cases. Other forms of bone tumors were verified in 13.3%. In the early postoperative period patients were without previous discomforts. Future treatment consisted of regular medical check-up of all the patients. In order to verify the final results, in February 2002 another medical check-up was performed for 11 patients, upon their consent. All of the patients with verified osteoid osteoma were without discomforts. Medical findings were regular in each case. Conventional radiography showed a solid bone remodelling in place of resected bone.

CONCLUSION

Osteoid osteoma is a benign bone tumor with typical clinical and radiographic findings. Operative treatment represents a method of choice and demands accurate preoperative localization of the lesion, with the help of computer-assisted tomography.

[Diagnostic significance of synovial biopsy in patients with Reiter's syndrome]

INTRODUCTION

Arthritis in Reiter's syndrome (RS) is a reactive synovitis associated with a localized infection of the urogenital or gastrointestinal tract with a genetic predisposition. The pathogenetic mechanisms for synovitis in RS are still unknown. Our aim was to examine some of the pathogenetic mechanisms in Reiter's syndrome looking for morphologic changes, immunoprotein deposits and microorganism antigens in synovial biopsies and to determine whether synovial biopsy is useful in diagnosis of RS.

MATERIAL AND METHODS

Thirty patients with urogenital form of RS were examined within a four-year period. Table 1 illustrates laboratory findings in our patients. We performed synovial biopsies looking for histopathological changes, deposits of immunoproteins and microorganism antigens. Analysis of synovial biopsy specimens was performed using light and immunofluorescence microscopy and fluorescein-labelled monoclonal antibodies to Chlamydia trachomatis.

RESULTS

Histopathological examination of synovial membrane revealed marked proliferation of the synovial lining cells (SLC) with less or more abundant papillary projections, hypertrophic and edematous tissue with marked vascularisation in 28 (93.3%) cases. Fibrinoid necrosis foci were seen on the surface of synovial tissue. Chronic inflammatory cells (CIC) were diffusely distributed. Edema of the vessel walls, swollen endothelial cells, fibrinoid necrosis in vessel walls as well as multilaminated basement membranes were observed. All histopathologic changes are presented in Table 2. Immunofluorescent techniques in 12 out of 30 (40%) synovial membranes showed immunoglobulin deposits: IgG and IgA deposits were found in vessel walls in 7 cases each and IgM in 10 biopsy specimens. C3 was present perivascularly or within the vessel wall in 4 (13.3%) cases. Sections treated using fluorescein-conjugated antibody revealed Chlamydia in the synovial tissue in 2 patients.

CONCLUSION

Biopsy specimens with previously described changes in patients with suspected Reiter's syndrome can be useful to confirm the diagnosis. According to our experience, multiple biopsies of abnormal synovia are recommended in these patients.

Diagnostic value of pericardial biopsy: improvement with extensive sampling enabled by pericardioscopy

BACKGROUND

The clinical significance of pericardial biopsy is controversial. The aim of this study was to assess the feasibility and diagnostic value of 3 approaches to pericardial biopsy: fluoroscopic control and standard sampling, pericardioscopy guidance with standard sampling, and pericardioscopy guidance with extensive sampling.

METHODS AND RESULTS

Forty-nine subsequent patients with a large pericardial effusion underwent parietal pericardial biopsy. In group 1 (12 patients, 66.7% males, age 46.7+/-12.2 years), pericardial biopsy was guided by fluoroscopy (3 to 6 samples per patient). Group 2 included 22 patients (50% males, age 50.8+/-10.4 years) undergoing 4 to 6 pericardial biopsies per patient guided by pericardioscopy (16F flexible endoscope). In group 3, extensive pericardial sampling was performed, guided by pericardioscopy (15 patients, 53.3% males, age 53.7+/-12.8 years, 18 to 20 samples per patient). Sampling efficiency was better with pericardioscopy (group 2, 84.9%; group 3, 84.2%) compared with fluoroscopic guidance (group 1, 43.7%; P<0.01). Diagnostic value was defined as a new diagnosis uncovered, etiology revealed, clinical diagnosis confirmed, and the biopsy false-negative. Pericardial biopsy in group 3 had higher diagnostic value than in group 1 in revealing new diagnosis (40% versus 8.3%, P<0.05) and etiology (53.3% versus 8.3%, P<0.05). In group 2, pericardial biopsy had a higher yield in establishing etiology than in group 1 (40.9% versus 8.3%; P<0.05). Pericardial biopsy was false-negative in 58.3% in group 1 in contrast to 6.7% in group 3 (P<0.01). There were no major complications.

CONCLUSIONS

Pericardioscopic guidance enhanced pericardial sampling efficiency. The diagnostic value of pericardial biopsy was significantly improved by extensive sampling made possible by pericardioscopy.

[Cytologic features of ameloblastoma]

Ameloblastoma is a rare tumor of the jaw arising from odontogenic epithelium. There are sparse reports in the literature concerning cytologic features of this tumor. This paper presents two cases of ameloblastoma, diagnosed by imprint cytology and confirmed histopathologically. The imprints were hypercellular, with single cells and the groups of basaloid and polygonal squamous cells with huge vacuoles in cytoplasm. Stellate and fusiform cells were found in the background of the preparation. These morphologic parameters were sufficient for the cytologic diagnosis of ameloblastoma.

[Advanced prostatic carcinoma with low levels of serum prostate-specific antigen]

The serum levels of prostate-specific antigen (PSA) represent a significant diagnostic and monitoring parameter of prostatic carcinoma (PC). The aim of the study was to establish correlation of serum PSA level in addition to grade, histological type, and clinical stage of PC in patients with normal or intermediary PSA serum level. In 37 untreated PC patients with preoperative serum PSA levels ranging between 0.1 and 9.6 ng/ml, paraffin-embedded tissue and serum samples were immunohistologically studied and immunoassay for PSA was done. The most representative was poorly differentiated PC with D stage. In serum samples from PC patients 27 (73.7%) normal (< or = 4.0 ng/ml), and 10 (27.3%) intermediate (4.1-10 ng/ml) PSA levels were found. Immunohistochemistry, in 36 PC (97.3%) had demonstrated the expression of PSA. Our study results had shown low serum PSA levels in some patients with advanced poorly differentiated PC.

[Tumor markers in pleural effusions in bronchogenic carcinoma and tuberculosis]

Concentrations of carcinoembryonic antigen (CEA) and carborhydrate antigen (CA) 50 were measured in pleural effusion and sera of 57 patients with bronchogenic carcinoma and in 73 patients in whom the effusion was the sequela of tuberculous pleurisy. In the group with bronchogenic carcinomas, planocellular was confirmed in 19, microcellular in 17, macrocellular in 2, and adenocarcinoma in 18, while in 1 patient it was not possible to determine the histopathologic structure. The diagnosis of pleural disease was established upon the cytologic examination of the effusion and histopathologic examination of the pleural sample obtained by blind percutaneous needle biopsy or following pleuroscopy. CEA concentration in the sera of patients with bronchogenic carcinoma was significantly higher than in the patients with tuberculosis (p < 0.001), with sensitivity of 44% and ideal specificity and positive predictive value of 100%. In the same group highly significant difference of mean values of CEA concentrations in pleural effusion (p < 0.001), was also found with sensitivity of 60%, significant specificity of 99% and positive predictive value of 97%. CA 50 concentrations in the sera of patients with lung carcinoma were significantly higher than those in the sera of patients with tuberculous pleurisy (p < 0.05), and the sensitivity was 50%, while the specificity was 94% and positive predictive value was 75%. Significantly higher was also the value in the pleural effusion (p < 0.05), but the sensitivity was slightly lower--40%, but specificity was favorable as well as the positive predictive value (94 and 86%, respectively). The results indicate the significance of the determination of CEA and CA 50 in the sera and pleural effusion in the differentiation of malignant from tuberculous pleural effusion.

[Successful surgical removal of a cardiac myxoma from the left ventricular outflow tract]

The precondition for successful, exclusively surgical treatment in the extracorporeal circulation, is the precise diagnosis of heart myxoma, particularly in rare locations such as the left ventricle. We present a case of myxoma in the outflow tract of the left ventricle as the exceptionally rare location, successfully diagnosed and surgically treated at the Clinic for Cardiac and Thoracic Surgery of the Military Medical Academy. A female patient, aged 46 years, was sent from another hospital with misdiagnosis of idiopathic hypertrophic subaortic stenosis. The patient was successfully operated after transthoracic and transesophageal echocardiography as the main diagnostic procedures. Myxoma that completely obstructed the aortic opening if pulled, was completely removed through aortic valve in the extracorporeal circulation. Its pedicle was arising from the ventricular side of the great mitral cusp. Postoperative course was uneventful and the patient was released from the hospital on the tenth postoperative day.

[Primary liposarcoma of the pericardium]

A case of primary liposarcoma of the pericardium, an exceptionally rare localization, has been presented. The tumor localized in the region of the left ventricle and connected to the visceral wall of the pericardium was diagnosed in a 38-year old male. Histological, histochemical and immunochemical findings confirmed the diagnosis of the liposarcoma of the pericardium.

[Primary liposarcoma of bone]

A case of 75-year-old man with extremely rare primary liposarcoma of the bone was presented. Stains for lipid, Sudan III, Sudan IV, and Oil Red "O", demonstrated the presence of intracellular lipid in the lipoblasts. Similarly, the S-100 immunoreactivity and electron microscopic findings of tumor cells confirmed the diagnosis of liposarcoma. Histochemical stains for PAS, Alcian-blue, mucikarmin, Toluidin-blue and Coloidal Iron were negative.

[Ameloblastic fibro-odontoma]

Ameloblastic fibro-odontoma is a rare malformation which is classified in group of odontomas, such as simplex and compound odontomas. A lesion usually develops asymptomatically in the first or the second decade of life, near the non-erupted or displaced tooth, consisting of numerous small tooth-like components. This is a case report of a 10 years old boy with tumor-like lesion in the angle of mandibula in whom was confirmed ameloblastic fibroodontoma after the operation and histological examination. Considering the growth potential and its clinical features, ameloblastic fibroodontoma requires adequate surgical treatment.

[Histopathologic changes in the skin of transplanted microvascular flaps]

During the microvascular transfer, the free flaps tissue is exposed to series of pathophysiological changes (tissue anoxia, tissue acidosis, anaerobic metabolism, wound healing and cicatrisation, degeneration of nerves fibers in the free flaps tissue, etc.) In 1993-1998 period, at the Clinic for Plastic Surgery and Burns at the Military Medical Academy, we analyzed histopathologic changes in the skin taken from the transferred flaps and from the recipient region surroundings of 31 patients with microvascular tissue transfer. The bioptic materials were taken between 6 and 36 months following the free tissue transfer--average 23.6 months. By light microscopy we analyzed histopathologic changes of the epidermis, collagen's fibers, skin adnexa, blood vessels and nerve fibers. The data obtained showed considerable difference in the histopathology test results of the epidermis, collagen's fibers, the skin adnex and the nerve fibers in the transferred free flaps compared to the results obtained from testing recipient region surroundings. The histopathologic tests of the blood vessels did not show considerable comparative difference.

[Myositis ossificans in recurrent synovial hemangioma of the knee]

A case of myositis ossificans in 15-year old boy that occurred as a complication of the recurrent synovia hemangioma of the left knee was presented. The alteration was diagnosed as: osteosarcoma, chondrosarcoma and chondromyxoid fibroma by the pathologists from other institutions. The diagnosis of myositis ossificans was established using numerous histochemical and immunochemical methods (PAS, PAS diastasis, Alcian blue, Masson trichrom, von Kossa, Azur A, Toluidin blue, Goldner, method by Peris, Citokeratin, S-100, NSE and Vimentin). The presence of zonal phenomenon, as the one observed in the presented case, is one of the most significant criteria for differentiation of myositis ossificans from osteosarcoma.

[Ochronosis--an autopsy case report]

The authors have presented a case of ochronosis, as the incidental finding during the autopsy of a female patient, aged 59 years. It was the case of suicidal drug poisoning. Ochronosis is a rare disease, with chronic benign course, but frequently followed by complications. Histopathological criteria for the diagnosis of this disease are described in detail.

[Pigmented villonodular synovitis--analysis of 50 patients]

Fifty patients with pigmented villonodular synovitis (PVNS) were examined and treated in the Military Medical Academy in twenty-year period (1977-1996). Among them, 32 were male and 18 female (2:1), of average age from 6 to 72 years. Articular disease localization was 2.5 times more frequent compared to the non-articular. The rate of circumscribed in relation to diffuse form was 1.5:1. The ankle joint was most frequently involved (94%). In one patient, PVNS was proved in both ankle joints. The disease was clinically expressed as chronic, and 4 times more frequently as chronic recurrent synovitis. The data of previous injury were known in 14 patients. Associated rheumatic disease or injury was found in more than a half patients (53%). For the disease diagnosis there were used: physical examination, standard laboratory tests, radiography, ultrasonographic and magnet resonance examination and histopathologic examination of synovia obtained by open or arthroscopic biopsy. Surgical methods, such as total or partial synovectomy were applied in the therapy. Chemical synovectomy was performed in one patient, 6 months after the diagnostic arthroscopy due to disease recurrence. Therapeutic effect was estimated in 22 patients, from 3 months to 11 years after the surgery on the basis of disease recurrence. Except for the cited one patient, none other had the disease recurrence. It was concluded that timely diagnosis of PVNS offered more adequate treatment and conditions for complete recovery. In the disease limited just in the ankle joint, arthroscopic synovectomy would be the therapy of choice. In advanced diffuse form, total synovectomy should be performed for all the disease localizations.

Morphologic characteristics of primary nonperforative intestinal blast injuries in rats and their evolution to secondary perforations

Five hundred and fifty Wistar rats were investigated to determine the frequency of secondary intestinal perforations after exposure to nonperforating blasts and the evolution of the morphological changes from hematoma through to necrosis and gangrene. The animals were observed at different times for a period of 14 days from the moment that the injury was inflicted. Microscopic findings showed that alterations began in the mucosal layer where they were most extensive, then spread to the submucosal layer, muscular layer, and serosal layer, respectively. Examination of the intestinal wall revealed an evolution of the injury from hematoma to necrosis to gangrene, resulting in secondary intestinal perforation. The secondary wounds had centrifugal patterns, opposite those of the original wound pathways. Based on these observations, the mechanism of evolution of primary nonperforating intestinal blast injury into secondary intestinal perforations is presented.

Morphological analysis of saphenous vein used for aortocoronary graft

Histological, histochemical, immunohistochemical and ultrastructural analyses of 120 saphenous veins (of 120 patients) prepared for aortocoronary graft, revealed in 57 cases lesser or larger morphological changes, such as endothelial damage, hyperplasia of t. intima, or t. media, and fibrosis of t. adventitia that could be the result of postoperative complications (thrombosis of the graft lumen, or its occlusion due to progressive hyperplasia of t. intima). The analyses have proved significantly increased number of smooth muscle cells and fibroblasts in t. intima of the damaged veins in relation to t. media, contrary to the findings in normal veins, and it was suggested that these smooth muscle cells in the damaged veins migrated from t. media to t. intima causing hyperplasia, as was confirmed by histochemical, immunohistochemical and ultrastructural findings. Since in 57 of 120 analyzed veins morphological changes were found which developed before the implantation of vein and which could compromise the vein function as the aortocoronary graft and cause severe postoperative complications, forming of vein banks is recommended from the chosen donors to avoid vein implantation with the already existent morphological changes, that could be proven by their immediate histological examination.

Histopathological evaluation of the carbon fibers application for the substitution of the anterior cruciate ligament--an experimental study on dogs

The application of allograft-carbon fibers on the experimental group of 15 dogs (German Shepherd race) was histopathologically investigated after the artificial lesion of anterior cruciate ligament (ACL). In definite time intervals (1, 2, 4, 6 months) pathoanatomic and histopathologic findings were analyzed and the proliferation of new connective tissue of predominantly elastic type, between carbon fibers was observed. Beside the lymphocyte infiltration around torn carbon fibers giant cells of a foreign body type were found, and on the surface the epithelium similar to synovial was observed. It was concluded that carbon fibers could not be considered as the ideal artificial ligament.

The use of autografts and synthetic carbon fibers in reconstruction of the anterior cruciate ligament--an experimental study on dogs

Biological characteristics and strength of the anterior cruciate ligament (ACL) after replacement by an artificial carbon fibers ligament--(group 1) and autograft--fascia lata (group 2) were investigated. These two methods were compared in four periods of time by means of clinical course, laboratory parameters, histopathological analysis and biomechanical testing on an Instron apparatus. Strength of neoligament in both examined groups has never achieved the strength of natural, unaffected ACL, and there was no significant difference between two observed groups in relation to clinical and laboratory parameters. Histopathological examination showed the presence of ingrowing of the connective tissue between carbon fibers, but in bone tunnels inside the fibers there was no ingrowing between bone trabeculae. In the group 2, collagenic fibers of the fascia lata were substituted with predominantly elastic connective tissue, with epithelium, similar to synovial, on the surface. No absolute superiority of carbon fibers to fascia lata as a substituent of the anterior cruciate ligament of a dog knee, as an experimental analog, was proved in this study.

[Anatomic characteristics and clinical signs of congenital anomalies in the circle of Willis]

Anatomical characteristics and clinical importance of congenital anomalies of cerebral arteries were examined based on the results obtained by dissection of the circle of Willis blood vessels of 70 native cadaveric brains. Anomalies were most frequently found in posterior communicant artery and their most frequent type was hypoplasia of the blood vessel. Multiple anomalies of the circle of Willis were found in 3 cadavers. Premortal neurological symptomatology (PNS) existed in 5 cadavers. There was no significant difference in PNS occurrence at autopsy in cases with or without anomalies. Association of aneurisms with anomalies of the circle of Willis was found in two cases, but it was not significant in comparison to the control group with no anomalies.

[Immediate results of surgical treatment of intracardiac myxomas in 45 patients]

Between 1961 and 1992, 45 patients with intracardiac myxomas localised in the left ventricle--40 (89%) and in the right ventricle--5 (11%) were operated on. There were 27 women and 18 men, aged 15-63, mean age, 46.5 years. Three patients were asymptomatic while in other dominated different degree of malfunction of the corresponding atrioventricular valve, mainly with dominant symptoms and signs of stenosis. In 5 patients (11%) myxoma of the left atrium was in question together with systemic embolization. The diagnosis was established both by invasive and noninvasive methods and the method of choice, very reliable and easy, has proved to be echocardiography. All patients were operated on with the use of the total cardiopulmonary bypass and induced heart arrest. The histologic verification of all excised myxomas was performed. Three early deaths occurred (6.6%), while in other patients no postoperative complications developed. It has been concluded that echocardiography is very safe diagnostic procedure and results of surgical treatment are very good.

[Hemangiopericytoma of the lungs]

Six patients, three women and 3 men with lung hemangiopericytoma treated at the Military Medical Academy in the period 1971-1991 are reported. The youngest patient was 20 years, the oldest 69 years. Surgical treatment was performed in all patients, 3 lobectomies, one bilobectomy, one wedge resection and one extirpation. Multiple hemangiopericytoma was found in one patient which consisted of three separate tumours in the right lung. The other had solitary lesions. Malignant hemangiopericytoma, was found in 4 patients, one of them had metastases in the mediastinal lymphatic glands. Four patients are alive and are under control for nine years in the average without signs of recurrence.

[Analysis of intracranial aneurysms from autopsy material]

The analysis of 44 intracranial aneurysms found at 7.687 autopsies is performed. The largest number of aneurysms was of congenital (secular) type, then, of arteriosclerotic type while inflammatory and traumatic aneurysms were very rare. The elastic and reticular fibres in the aneurysmal wall and the normal arteries of the base of the brain were identified by a standard and special staining. Significantly decreased quantity and disturbed distribution of the reticular fibres were found in the congenital aneurysms which was considered to be a consequence of degenerative processes. The finding of the preserved elastic internal lamina in the wall of the congenital aneurysm and its absence or fragmentation in cases of arteriosclerotic aneurysms suggest the different etiology and pathogenesis of these aneurysms.

[Ultrastructural changes in the dermal blood vessels in patients with psoriasis]

The ultrastructural analysis of psoriatic dermal lesions has shown the alteration of the dermal arterioles into specialized postcapillary venules, the so called high endothelial venules (HEV) which are characterized by the presence of tannic acid staining materials (TASM) located among the endothelial cells. This type of venules seen in the lymphatic nodes and other lymphoid organs is considered to be an important site of lymphocyte recirculation. Similar venules are seen in the lymphatic nodes too. In correlation with the immunologic evidences in the lymphoid tissues and in psoriasis most probably in question are the identical surface antigen-lymphocyte receptors on the HVE which support selective binding of the definite subset of lymphocytes and migration from blood to tissues.

[Malignant fibrous histiocytoma of the bone]

Five cases of malignant bone fibrous histiocytoma diagnosed by bioptic material are presented. The authors state that the diagnosis of these rare bone malignant neoplasms do not present a larger diagnostical problem. However, some differential diagnostic problems are often met compared to other bone neoplasms, especially in osteosarcoma, so in these cases are recommended that together with routine histologic examinations in establishment of diagnosis should be also used enzymohistochemical methods, especially alkaline and acid phosphatase. Also, it is necessary to use immunohistochemical methods with corresponding markers which the authors have used in establishment of diagnosis of their cases. Based on the analysis of the presented cases the authors support the theory of J. Brooks on the histogenesis of these tumours within his theory of differentiation of the mesenchimal tissue which is easily recognized in recidives and metastases of soft tissue sarcomas by phenotypes organized at the lower level of differentiation.

[Similarities in morphologic changes in heart valves in acquired heart defects of noninflammatory etiology and in damaged menisci without a history of trauma]

Histologic, histochemical and ultrastructural analyses were performed of the leaflets of all four heart valves in 50 subjects with acquired heart defects of noninflammatory etiology and 88 surgically removed damaged menisci without trauma anamnesis. On the basis of the detailed analysis some morphologic similarities were found in the heart valves and menisci such as myxomatous degeneration as the main pathologic lesion, lack of blood vessels in the altered tissues which point to noninflammatory nature of the lesion, similarity in nourishment by diffusion, degradation of the collagenous fibres which present the main histologic structure and the increased accumulation of acid mucopolysacharrides at the site of their degradation as well as the increased number of fibroblasts, that is, chondroid cells which are considered to excrete acid mucopolysacharrides. Sometimes these changes are hardly identify clinically, especially in meniscal diseases which could simulate rheumatic disease.

[Tuberculous inflammation of the synovial membrane]

Four patients with tuberculous synovitis of the large joints are reported in whom primary tuberculous process has not been confirmed as a possible foci of spreading of the acidoresistant bacilli. The authors, describing in details the histologic picture of tuberculous synovitis, point out the importance of an early biopsy of the synovial membrane and obligatory microbiological confirmation of the established diagnosis.

[Hürthle cell carcinoma of the thyroid gland]

The authors have analysed 9 cases of Hürthle cell thyroid carcinoma diagnosed on the bioptic material in the period 1975-1991. In 7 patients subtotal and in 2 total thyroidectomy was performed. In one patient only signs of metastases of the tumour in the region of the mediastinum, neck lymphatic nodes and brain developed and the patient died a year after surgery. For differential diagnosis of Hürthle cell thyroid carcinoma and Hürthle cell adenoma the authors recommend as necessary that beside the presence of the basic criteria for malignancy (infiltration of the capsule and adjacent tissue, invasion of the blood vessels, pleomorphism and pathologic mytoses) the electron microscopic examination and immunohistochemical methods should be also used which could be of a great help for establishment of a correct diagnosis on which depends further therapy as well.

[Morphologic changes in the valves in acquired heart defects]

The histologic, histochemical and ultrastructural changes of the leaflet tissue of all four cardiac valves obtained by biopsy and autopsy have been studied in 50 patients with acquired valvular defects. The anamnesis confirmed the presence of rheumatic fever in 16 patients and negated it in 34 patients. In all analysed leaflets of all four cardiac valves organic changes were found which were the cause of their dysfunction. The analysis has shown that rheumatic fever does not play a dominant role in development of acquired valvular disease as it has been thought previously. However, degenerative changes were most commonly found being of unknown etiology up to now. The morphological changes of valvular tissue in the patients suffering from rheumatic fever differ from those who did not suffer from it. Vascularization, fibrosis and hyalinization of the connective tissue with fibroelastic densities predominated in patients suffering from rheumatic fever while myxomatous degeneration of valvular tissue predominated in those who did not suffer from it. Different morphological parameters indicate the different etiopathogenesis of these diseases.

[Intraosseous schwannoma]

Neurogenic tumors, primary bone tumors, are rather exceptional; about 50 cases have been reported so far. The study reports a case of intraosseous schwannoma, a primary bone tumor, in a 20-year-old male patient, localized in the distal end of the right tibia.

[Morphologic damage in internal organs in miners caused by explosions of methane gas in mines]

Four cases of blast injuries in miners caused by methane explosion in the mine are described. In all cases besides burns, changes in tissues and organs, according to their microscopic and macroscopic characteristics, corresponded to blast type injuries described in the literature.

[Morphologic changes in the tissues and organs of sheep in blast injuries caused by detonation of aerosol explosives]

The morphologic changes of the tissues and organs of sheep caused by effects of the overpressure wave due to the detonation of the aerosol explosive in the open air are analysed. The experiments were performed on 21 sheep of which 3 served as the control. All animals were autopsized and organ samples were taken for analysis. The most impressive pathologic changes were found in the upper respiratory ways and lungs in the form of massive haemorrhage, edema and emphysema as well as numerous and severe intraabdominal changes both of the air-containing and parenchymatous organs.

[Morphologic characteristics of persons killed in armored vehicles]

The authors have analysed macroscopic and microscopic changes in tissues and organs of 8 members of the Y.P.A. killed by granate explosion in the armoured vehicles. In all the analysed cases multiple mechanic injuries were found as well as combined mechanothermal injuries. Injuries caused by the blast wave were mainly found in the internal air-containing organs and three cases of solid blast injury were described too.