[Diagnostic electron microscopy].
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Biomedical subjects
Publications and source records attributed to J J Navas Palacios.
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We report the twentieth case in the world literature of testicular malacoplakia. This lesion occurs mainly in middle-aged men, appearing clinically as epididymo-orchitis or enlargement of the testicle with fibrous consistency and some soft areas. Malacoplakia is now considered a nonspecific inflammatory granulomatous lesion subsequent to an infection by gram-negative bacteria. In our case Escherichia coli was cultured in the urine and testicular tissue. The ultrastructural study shows the histiocytic nature of the cellular infiltrate as well as the morphology of Michaelis-Gutmann bodies. Bacilliform structures were not found. The cellular and humoral immunological studies did not show alterations.
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Ten cases of T-lymphoblastic lymphoma/leukemia were studied with light and electron microscopy. Cytochemical strains were performed on touch preparations, and mononuclear cell suspensions were tested for spontaneous rosette formation with sheep erythrocytes, C3 receptors, and surface immunoglobulins. The present investigation was performed to evaluate several ultrastructural parameters, mainly the nuclear shape, as diagnostic clues for this group of lymphomas. Characteristic convoluted nuclei were present in 7 to 47% of the lymphoblasts. This percentage correlated with the focal acid phosphatase reaction and E-rosette formation. Acid phosphatase was the best cytochemical marker (70-100% of the lymphoblasts showed focal reaction product). By ultrastructural cytochemistry, the reaction product was demonstrated in the Golgi cisternae and primary lysosomes. The cell suspensions obtained from different sources contained 14 to 95% E-rosette-forming cells. No specific morphologic, cytochemical, or immunologic differences were found between patients with or without mediastinal involvement.
Idiopathic mesangial glomerulonephritis with IgA deposits was observed in two relatives, father and son, in a family of 5 members. In the father the disease started at age 43 with relapsing macroscopic hematuria, proteinuria, renal failure and hypertension, with a progressive course in the ensuing four years. The affected son, the oldest of three brothers, developed relapsing macroscopic hematuria at age 16; two years later renal function was normal and there was no hypertension, but microhematuria persisted without proteinuria. The mother and the other two brothers had no clinical or biological signs of renal disease. Serum immunoglobulins (IgG, IgA, and IgM) and complement (C3, C4, C3 proactivator) were normal in the patients and their relatives. Histocompatibility typing demonstrated the presence of HLA-Bw35 in the father and the two unaffected sons, being negative in the mother and the affected son. The analysis of HLA-Bw35 in 23 patients with IgA mesangial glomerulonephritis gave positive results in 30% of them, while the control group had a positivity of 15% (p non significant with the X2 test). The present observations suggest that IgA mesangial glomerulonephritis is a potentially familial and hereditary renal disease. HLA-Bw35 antigen appears not to be a genetic marker of the disease in our geographical area.
An 11-year-old white boy had a melanotic neuroectodermal tumor of infancy (MNTI) in his right mandible. Gross-examination showed that the tumor had originated in the right lower dental nerve, destroyed the right mandible, infiltrated the surrounding soft tissues, and metastasized to several lymph nodes. The typical alveolar pattern was observed in most of the tumor mass; however, solid areas with neuroblastic features were present in the infiltrating and metastasizing portions of the tumor. Ultrastructural study demonstrated unequivocal neuroblastic and melanocytic differentiation.
Angioimmunoblastic lymphadenopathy is a rare clinical entity, first described in 1974, characterized by asthenia, anorexia, fever, sweating, generalized lymph node enlargement, hepatosplenomegaly, rash, hypergammaglobulinemia, and often Coomb's positive hemolytic anemia. Main histopathologic findings are lymphoplasmocytic and immunoblastic proliferations, increased vascular neshwork and interstitial granular PAS positive material deposits. A lymph node excised from a woman with angioimmunoblastic lymphadenopathy was examined under electron microscopy. Results of ultrastructural study are compared to the typical histologic pattern observed under light microscopy. Analysis of the cellularity and the significance of fibrous collagen found in the interstitial PAS positive material are commented on.
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OBJECTIVE: To determine immunohistochemically the expression of mutant p53 phosphoprotein in hepatocellular carcinoma (HCC) and its possible relationship to several etiologic factors. STUDY DESIGN: The study group consisted of 62 samples of HCC, grades 2, 3 and 4, obtained by fine needle aspiration cytology. The associated risk factors detected in these patients were as follows: ethanol abuse, ethanol abuse plus hepatitis B virus (HBV) or hepatitis C virus (HCV) infection, HBV infection, HCV infection, non-A/ non-B hepatitis, hemochromatosis and obesity. RESULTS: Mutant p53 expression was identified in 22% of HCC and seemed to correlate with tumor grade. Positive immunostaining was frequently associated with a history of alcohol abuse (42%) and also with viral infection (HBV, 21%; HCV, 7%; non-A/non-B hepatitis, 7%). CONCLUSION: Mutant p53 seems to intervene in the progress of HCC through various grades of increasing malignancy. The association we found between alcohol intake and mutant p53 expression may deserve further investigation.
A case of primary adenocarcinoma of the vagina in a 46 year old woman is reported. The light and electron microscopic studies are highly suggestive of a Müllerian origin. The ultrastructural features are discussed in relation to clear cell adenocarcinoma of the vagina, establishing the differences between them.