Leydig cell tumor of the testis: a cytohistological, immunohistochemical, and ultrastructural case study

We report a case of Leydig cell tumor of the testis in a young man, in whom preoperative diagnosis was achieved by fine-needle aspiration biopsy cytology. Cytology, histology, and ultrastructural examination showed diagnostic Reinke's crystals, both in nuclei and in cytoplasm. Immunohistochemistry displayed strong vimentin and estrogen positivity.

Kindler syndrome: report of a case with ultrastructural study and review of the literature

Kindler syndrome is characterized by a generalized, progressive poikiloderma with cutaneous atrophy, congenital acral skin blistering, and photosensitivity. Since the first description, approximately 70 cases have been reported worldwide, but ultrastructural studies were performed in only five patients. In none of these patients were biopsies done at birth. In our patient ultrastructural studies were performed both of the blister at birth and of the poikilodermatous and atrophic skin at 6 years of age. Some ultrastructural features in the context of a bullous disease of the newborn that resembles epidermolysis bullosa, should alert investigators to the possibility of Kindler syndrome even in absence of the typical clinical signs.

Solitary left ventricle metastasis by renal cell carcinoma with sarcomatoid features

A 64 year-old male presented with a mass of the left kidney, 9 cm across. A radical nephrectomy was performed and the pathological examination of the surgical specimen revealed a large papillary renal cell carcinoma (RCC). Five weeks after surgery, the patient died because of progressive cardiac failure. At autopsy, a whitish-gray subendocardial mass, measuring 6 cm in its main diameter, was discovered in the left ventricle. Histologically, the tumour, consisted of interlacing bundles of spindle cells, showing large vesicular nuclei, with prominent nucleoli. Rare gland-like structures lined by neoplastic cells were occasionally found. Neoplastic cells were focally immunoreactive to anti-cytokeratin and anti-epithelial membrane antigen antisera. The diagnosis was that of cardiac involvement by RCC with sarcomatoid features. Cardiac metastases by RCC are rare and their incidence ranges from 1.3% to 4.2%. In the present case, the sarcomatoid appearance of the cardiac lesion raises the problem of the differential diagnosis with primary cardiac sarcoma. The clinico-pathological features of this case are discussed and the literature on this topic is reviewed.

Human epidermal Langerhans cells express the ICAM-3 molecule. Immunohistochemical and immunoelectron microscopical demonstration

Three ligands have been described for the leucocyte integrin LFA-1, namely intercellular adhesion molecule (ICAM)-1, ICAM-2, and ICAM-3. ICAMs show differences in tissue distribution and inducibility. The recently described ICAM-3 is highly expressed on resting lymphocytes, monocytes and neutrophils. Here, we demonstrate that the whole human epidermal Langerhans cell (LC) population expresses this molecule. Immunohistochemical staining of skin sections with an anti-ICAM-3 monoclonal antibody displayed reactivity with dendritic epidermal cells regularly distributed along the epidermis. Highly-sensitive immunoelectron microscopy procedures, performed on freshly suspended epidermal cells both at transmission and scanning electron microscopic levels, enabled demonstration that the whole LC population expresses cell surface ICAM-3. In contrast, keratinocytes and melanocytes were consistently negative. The prominent expression of ICAM-3 by resident LC could imply a crucial part for this molecule in leucocyte-intercellular interactions in the skin.

Filamentous inclusions in nonneoplastic and neoplastic pancreas: an ultrastructural and immunogold labeling study

Filamentous inclusions (FI) are unusual, irregularly shaped cytoplasmic inclusions, which are mostly found in acinar cell carcinomas of the pancreas and are consequently thought to be an abnormal zymogen granule type. This study describes identical inclusions in acinar, centroacinar, and small duct epithelial cells from nonneoplastic pancreas, as well as those found in tumor cells from a mixed acinar-endocrine pancreatic carcinoma. An ultrastructural and immunogold labeling demonstration indicates that these inclusions are aggregates of intermediate filaments immunoreacting with the anti-cytokeratin AE1/AE3 mixture and with V9 clone anti-vimentin monoclonal antibodies. Their pleomorphic appearance, variable immunoreactivity, and frequent association with lipid droplets and secondary lysosomes, mostly of the angulate type, led to the hypothesis that the FI undergo a degenerative remodeling pathway similar to that proposed for hepatic Mallory bodies. A survey of the literature on FI and human tumors suggests that they are a variably expressed ultrastructural feature of tumor cells originating from exocrine cell-containing tissues, namely the pancreas and gastrointestinal tract.

Gastro-intestinal stromal tumors: an ultrastructural reinterpretation of the clear cell component

The histology, immunohistochemistry and ultrastructure of six gastro-intestinal stromal tumors of the stomach (GSTs) showing a focal to diffuse clear cell component are reported. At light microscopy, all GSTs had typical histopathological features with one case additionally displaying stromal myxoid changes and scattered multinucleated giant cells. Immunohistochemically, 6 of 6 GSTs stained positive for vimentin, 2 of 6 for smooth muscle specific actin and 1 of 6 for desmin. At electron microscopy, GSTs showed microfilaments with focal densities as well as other smooth muscle features, such as subplasmalemmal linear densities and foci of external lamina. Ultrastructural appearances of tumor cells with clear cell features showed these not to be an artifact of fixation, but the expression of an unusual cytophagocytic activity. Inclusions of auto- and heterophagocytic nature were found responsible for the origin of the large, mostly lipidic vacuoles which displaced cell nuclei peripherally in a signet-ring fashion. It is concluded that such previously unrecognized features are ultrastructural aspects of GSTs with smooth muscle differentiation.

Smooth muscle differentiation in normal human ovaries, ovarian stromal hyperplasia and ovarian granulosa-stromal cells tumors

An immunohistochemical and ultrastructural investigation on the presence of "smooth muscle differentiation" in stromal ovarian tissue was carried out in 10 adult granulosa cell tumors, six juvenile granulosa cell tumors, six thecoma/fibrothecomas, six cases of stromal hyperplasia, and in 10 normal ovaries. For immunohistochemistry, formalin-fixed paraffin-embedded tissues were processed using anti-alpha smooth muscle actin (alpha-SM actin) and anti-desmin as primary monoclonal antibodies. All adult granulosa cell tumors and juvenile granulosa cell tumors showed an intense alpha-SM actin immunoreaction, but weaker for desmin. Immunostain was diffuse in six out of 10 and five out of six adult granulosa cell tumors and juvenile granulosa cell tumors, respectively. Ultrastructurally, intermediate filaments focally converging into well developed desmosomes as well as peripheral bundles of myofilaments were documented both in adult granulosa cell tumors and juvenile granulosa cell tumors. In thecoma/fibrothecomas and stromal hyperplasia, alpha-SM actin and desmin expression was minimal or absent; on electron microscopy some "myoid" features and myofibroblasts were also seen. In normal ovaries, alpha-SM actin was found intensely expressed in the theca externa, focally identified in cortex-medulla, and unstained in the theca interna layer. Immunoreaction increased during folliculogenesis, going from a thin positive alpha-SM actin layer around secondary follicles to a strong diffuse stain in mature follicles. Our immunohistochemical and ultrastructural results indicate that a "smooth muscle differentiation" is a typical component of the specialized gonadal stromal tissue. A diffuse and focally alpha-SM actin is constantly present in granulosa cell tumors and thecoma/fibrothecomas, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

The morphology of elastin in non-specific and inflammatory abdominal aortic aneurysms. A comparative transmission, scanning and immunoelectronmicroscopy study

The maintenance of the mechanical properties of the vessels results from the correct arrangement of smooth muscle cells and extracellular fibrous proteins (elastin and collagen) in their wall. The morphology of extracellular matrix modifications, particularly of elastin, was investigated in inflammatory (IA) and non specific (NSA) abdominal aortic aneurysms by scanning (SEM), transmission (TEM) and immunoelectron microscopy. Both NSAs and IAs were significantly characterized by extensive extracellular matrix remodelling, including different patterns of elastin degradation. Elastic and collagen fibres distribution appeared to be extensively altered in IAs, while it conformed more to a normal pattern in NSAs. With respect to NSAs, the morphology of elastic fibres in IAs was modified to such an extent that their identification by TEM had a rely on immunocytochemical methods and by SEM on back-scattered electron analysis. The observed ultrastructural changes are indicative of the central role of extracellular matrix modifications in the pathogenesis of IAs and NSAs.

Nuclear bodies associated with core particles of hepatitis B virus in a healthy carrier

An unusual association of nuclear bodies (NB) with core particles of hepatitis B virus (HBV) is described in a healthy carrier who histologically showed ground glass hepatocytes with occasional sanded-nuclei. Ultrastructurally, many hepatocytes had typical features of HBV infection. Unexpectedly, a few cells contained previously undescribed complexes of NB studded with a number of HBV core particles. The ultrastructural characteristics of these complexes and their possible relation to HBV morphogenesis are briefly discussed.

Trichomicosis pubis: black variety

A case of a 25 year old man with the black variety of trichomicosis pubis is presented on account of its extreme rareity. Scanning electron microscopy confirms that trichomicosis pubis is caused by bacterial colonisation of the pubic hair and shows that bacteria are able to penetrate cuticular horny cells directly through their free plasma membrane.

Fibrin sealant in laparoscopic adhesion prevention in the rabbit uterine horn model

OBJECTIVE

To assess the effects of fibrin sealant on adhesions after laparoscopic surgery.

DESIGN

Standardized surgical trauma was induced in 60 female rabbits. The animals were randomized in three groups for different adhesion prevention treatment.

SETTING

University research laboratory.

INTERVENTIONS

After standardized trauma was induced, group 1 (n = 20) received no treatment, group 2 animals (n = 20) were injected in the abdominal cavity with 60 mL of Ringer's lactate, and human fibrin sealant was applied on the surgical lesions under laparoscopic vision in group 3 (n = 20).

MAIN OUTCOME MEASURES

Five weeks after laparoscopy, a laparotomy was performed, and the adhesions were scored.

RESULTS

Fourteen of 20 rabbits in the control group (70%) presented postoperative adhesions, 11 of 20 (55%) in the Ringer's group, and 5 of 20 (25%) in the fibrin sealant group. High-score adhesions were seen in 15% of cases in control and Ringer's group and in 5% of cases in the fibrin sealant group.

CONCLUSIONS

When used during laparoscopic surgery, fibrin sealant has a preventive effect on de novo postsurgical adhesions. To assess the efficacy in reproductive surgery, a trial on recurrent postsurgical adhesions is required.

Expression of intermediate filaments in normal and neoplastic exocrine pancreas

The intermediate filament (IF) proteins present in the normal and pathological exocrine human pancreas were studied by immunolocalization using antibodies to cytokeratins (CKs) and vimentin. Acinar cells of normal pancreas showed a presence of simple CKs 8 and 18. Duct epithelium consistently expressed CKs 7, 8, 18 and 19 whereas centroacinar cells were rather low in CK 7. A subpopulation of CK 4 cells was detected in inter-intralobular ducts. In addition, some ducts contained individual cells or groups of cells that were positive for the stratification-related CKs (CKs 4, 5, 13, 15, 16). All pancreatic ductal adenocarcinomas regularly expressed CKs 7, 8, 18, 19 and were also positive for the 34 beta E12 antibody. Cytokeratin 4 was detected in a minor population of tumor cells. Pancreatic carcinoma also contained minor amounts of stratification-related CKs in variable combinations. Mucinous cystoadenocarcinoma showed the presence of CKs 7, 8, 18, 19 and was also positive for 34 beta E12, whereas the serous microcystic tumor presented CKs 8, 18, 19 and a variable amount of CKs 4 and 7. The duct-ductular alterations of the exocrine pancreas contained a different combination and distribution of CK isoforms similar to normal pancreatic ductal system. Mucinous hypertrophy and pyloric gland metaplasia reacted with antibodies to CKs 7, 8, 18 and 19. Vimentin was focally present both in normal and neoplastic tissue. Our results indicate that pancreatic ducts are characterized by an intrinsic "biliary-pancreatic duct type" immunoprofile (CKs 7, 8, 18 and 19), in contrast to acinar cells expressing exclusively CKs 8 and 18. We also detected a subpopulation of ducts regularly expressing CK 4. Surprisingly, several stratification-related CKs were detected both in normal and neoplastic exocrine pancreas. Moreover, the differentiation phenotypes of pancreatic tumors were reminiscent of normal cellular compartments.

Long-term cryopreservation of autologous veins in rabbits

This study was undertaken to determine the effect of long-term cryopreservation on graft ultrastructure and endothelial cell viability in an animal model. The jugular veins from 12 New Zealand White rabbits were excised with a 'no-touch' technique and divided into four groups: control group (fresh veins); group 1, veins cryopreserved for 1 month; group 2, veins cryopreserved for 2 months; and group 3, veins cryopreserved for 3 months. Cryopreservation was accomplished by rapid freezing (-5 degrees C s-1 to -196 degrees C) in a solution of 17.5% dimethylsulphoxide and 20% fetal bovine serum and by storage in liquid nitrogen. Veins were then implanted as a carotid autograft (three grafts/group). At the time of graft implantation a segment of the paired matched vein was perfusion-fixed and evaluated by scanning and transmission electron microscopy, whereas the remainder were subjected to endothelial cell culture techniques to determine cell viability. Autografts were removed 1 month after implantation and subjected to similar evaluations. Histological changes seen in cryopreserved veins were dependent on preservation time and included focal endothelial cell blebbing, cytoplasmic vacuolization and disruption of cell-to-cell contacts. Smooth muscle cells showed mitochondrial swelling. Patency was identical in all groups (66.6%). Explants at 1 month were similar in histological appearance to fresh veins with a smooth endothelial cell lining arranged longitudinally and intact cell junctions. Endothelial cells could be cultured from fresh veins and 1-month-old explants but not from the cryopreserved graft surface before implantation. the present technique of cryopreservation leads to some damage of graft architecture and loss of endothelial cell viability.(ABSTRACT TRUNCATED AT 250 WORDS)

Origin of unreactive hyaline bodies from erythrocytes in genital tumors

Two genital tumors, one a lipid virilizing cell tumor of the ovary, the other an ovarian Sertoli-Leydig cell tumor with retiform pattern, were studied focusing attention on the numerous eosinophilic hyaline bodies that were present both in the extracellular spaces and within the cytoplasm of the proliferating cells. Histochemistry and immunohistochemistry revealed that they were PAS positive and alpha-1-fetoprotein negative. Under electronmicroscopy these hyaline bodies appeared to correspond to variably altered red blood cells: red blood cell ghosts, erythrocytes with Heinz bodies, phagocytosed erythrocytes. Our findings could explain the origin of at least a part of the hyaline bodies found in similar or in other unrelated pathologies.

New insights suggesting a possible role of a heat shock protein 70-kD family-related protein in antigen processing/presentation phenomenon in humans

A possible role of the peptide binding protein (PBP) 72/74 in antigen processing and presentation has been recently suggested in mice. In order to evaluate a possible analogous role of a PBP72/74-related protein in humans, immunoelectron microscope investigations, functional studies, and immunofluorescence analyses were performed on normal human peripheral antigen-presenting cells. We demonstrated that the determinant recognized by antiheat shock protein (HSP) 72/73 monoclonal antibody (MoAb) is constitutively expressed on the cell surface of monocytes as well as of B cells. Moreover, the capability of monocytes to present a recall antigen to T cells was significantly decreased when preincubated with an anti-HSP72/73 MoAb. These data add further strength to a potential role of a protein related to human PBP72/74 homologue in antigen processing and/or presentation. Finally, the capability of anti-HSP72/73 MoAb to impair the ability of fixed monocytes to present a synthetic peptide demonstrates that cell surface-localized PBP72/74-related protein could play a role in antigen presentation.

Electron microscopic and immunocytochemical profiles of human subcutaneous fat tissue microvascular endothelial cells

The ultrastructural and immunocytochemical characteristics of microvascular cells from human subcutaneous fat tissue were studied after the addition of collagenase and Percoll density gradient, respectively. Monoclonal and polyclonal antibodies directed against antigens specific for endothelial cells (factor VIII, Ulex europaeus, CD31, and CD34), pericytes (muscle-specific actin and desmin), adipocytes (S-100 protein), and monocytes-macrophages (MAC 387 and 150.95 protein) were demonstrated by alkaline phosphatase monoclonal anti-alkaline phosphatase and protein A-gold techniques. In addition, to determine whether the harvesting method interfered with microvascular cell function, DOT immunoassays of factor VIII and CD34 were conducted on solutions recovered at collagenase incubation as well as after nylon filtration and Percoll administration, respectively. After the collagenase step, the vast majority of microvascular cells had the typical ultrastructural and immunophenotypical features of endothelial cells. In sharp contrast, following the Percoll step, only 1% to 18% of microvascular cells stained with factor VIII, Ulex europeaus, and CD31, whereas 90% of them expressed the CD34 antigen. Surprisingly, DOT immunoassay revealed the presence of factor VIII in the washing buffer recovered after the Percoll step only. Consequently the decreased expression of common endothelial cell markers (factor VIII, Ulex europaeus, and CD31) observed at the end of the cell isolation procedure was related to the adverse effects of Percoll on endothelial cell function. The CD34 surface molecule, being highly resistant, is particularly well suited for unequivocal characterization of microvascular cells as true endothelium.

A new polychrome stain and simultaneous methods of histological, histochemical and immunohistochemical stainings performed on semithin sections of Bioacryl-embedded human tissues

We describe a new polychrome stain and simultaneous methods of histological, histochemical and immunocytochemical staining performed on sections from human tissues embedded in the new hydrophilic resin Bioacryl. The polychrome stain involves the sequential use of Harris' Haematoxylin, silver methenamine, Light Green and Eosin or Safranin dyes and provides a highly specific visualization of the overall cytological tissue architecture. When histochemical, immunocytochemical, and polychrome stains are performed together on the same section, crisp images are obtained, yielding simultaneous data of histochemical and immunological reactivities with clear tissue architecture.

True and false aneurysms in Behçet's disease: case report with ultrastructural observations

One of the most important aspects of Behçet's disease is aneurysmal arteriopathy. The major problem of this complication is its tendency to develop recurrent false aneurysms at anastomotic and traumatic sites, such as angiographic punctures. We present a clinical case in which five aneurysms, some true, some false, were operated on during a period of 6 years, with the aid of ultrastructural observations of the wall of a true and a false aneurysm. One of the true aneurysms, localized in the aorta, was treated by direct aneurysmorrhaphy, and the 6-year follow-up demonstrated the absence of recurrences. Based on both this experience and the data in the literature, we suggest that the most appropriate surgical approach would, when possible, be direct aneurysmorrhaphy.

Demonstration of cytokeratin intermediate filaments in oocytes of the developing and adult human ovary

The intermediate filaments (IF) present in the various cells of human ovaries were studied by immunolocalization using antibodies to cytokeratins (CKs), vimentin, desmin and alpha-smooth muscle (alpha-SM) actin. Oocytes revealed a single paranuclear aggregate, which reacted with antibodies to CKs 8, 18 and 19 both in adult and fetal ovaries. The existence of this aggregate was also documented by electron microscopy. Ovarian surface epithelium and granulosa cells consistently coexpressed CKs 8, 18, 19 and vimentin. During follicle maturation vimentin remained unchanged in the granulosa layer while CKs content decreased, showing variation in the amount and distribution of the different CK-types. Thecal cells of secondary and mature follicles showed alpha-SM actin positivity. These contractile fibres increased in mature follicles. Ordinary fibrous stromal cells showed isolated cells which were desmin and alpha-SM actin positive. A similar pattern of IF expression and distribution existed in all stages of development in fetal and embryonic ovaries. These results indicate that CKs are present in human oocytes and that the coexpression of vimentin and CKs can be regarded as a peculiar feature of all ovarian cell types except oocytes and ordinary stromal cells. Contractile properties have been documented associated with a modification in expression of IF proteins. This is likely to represent an integral part of folliculogenesis along with the functional hormone-dependent changes.