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Biomedical subjects

M A Greco

Publications and source records attributed to M A Greco.

At least 109 records · Page 6Linked to original sources

Mucinous metaplasia of the endometrium: ultrastructural and histochemical characteristics.

The histologic, ultrastructural, and histochemical characteristics of a focus of mucinous metaplasia in the endometrium of a postmenopausal woman are described and compared with normal endocervical and endometrial epithelium. While, architecturally, the simple coiled metaplastic glands resembled endometrial glands, cytologically, they resembled endocervical cells in the ultrastructural appearance of the mucin, as well as in the histochemical-staining properties of the intracellular secretory product. The location of the focal area of metaplasia in the fundus, apparently isolated from endocervical mucosa, as well as its architectural resemblance to endometrium, indicates that it originates from endometrium rather than endocervix.

Endometrium↗

Histiocytosis-X: clonal culture, histocytochemistry, electron microscopy.

Pathologic interpretation of an osteolytic lesion from the skull of a 13-month-old boy was amplified by histocytochemistry of cells grown in a methylcellulose clonal culture system. Electron microscopy demonstrated the presence of X granules in the cytoplasm of malignant histiocytes, confirming a diagnosis of histiocytosis-X. Freshly fixed tissue containing histiocytosis-X cells and granulocytes showed histiocytosis-X cells that were positive for alpha-naphthyl acetate esterase (non-specific esterase) and negative with naphthol AS-D chloracetate as the esterase substrate (specific esterase). Clonal cell aggregates, harvested after 6 days' growth in culture, showed histiocytosis-X cells that were positive for both the nonspecific and specific esterases. Differences in staining reactions for the histiocytosis-X cells may be explained on the basis of immaturity of the histiocytosis-X cells growing in culture. This interpretation would support their origin from monocytes, monocytic precursors, or a still less differentiated myelomonocytic precursor cell. Furthermore, gel systems of clonally cultured cells appear to provide a useful tool for the growth and analysis of histiocytosis-X cells.

Clone Cells↗

Fibroblastic reticulum cells in human lymph nodes. An ultrastructural study.

The ultrastructural characteristics of the fibroblastic reticulum cell (FRC) in human reactive lymph nodes, which were studied electron microscopically, indicate a myofibroblastic cell with unique properties. Its contractile element is probably useful in controlling the volume of the lymph node and possibly in the movement of antigens and antibodies. The FRC may also play a role in other immunologic functions and seems to be preponderant in some lymphomas.

Aminosalicylic Acid↗

Iniencephaly: a neuropathologic study.

Five cases of iniencephaly are reviewed. Numerous central nervous system malformations were found at all levels, including microencephaly, polymicrogyria, heterotopic glial tissue in the leptomeninges, atresia of the ventricular system, marked disorganization of the brain stem, vermian agenesis, large cerebellar cyst, and disorganization of the spinal cord tissue. The cerebellum was normal in one case. Numerous skeletal anomalies were found as well as marked retroflexion of the craniocervical junction. We concluded that cerebral anomalies, although severe, are not specific for iniencephaly. Cerebellar anomalies, on the other hand, were considered to share some morphologic features between Dandy-Walker and Arnold-Chiari, i.e., Chiari type II and Chiari type III, malformations.

Abnormalities, Multiple↗

Successful excision of an atrial fibroma in a four-month-old male infant.

This report presents an infant who was initially admitted with a pericardial effusion. Subsequent evaluation led to the diagnosis of a primary cardiac tumor. Excision of the tumor which arose from the atrial septum was possible only by removing most of the free right atrial wall and a portion of the septal leaflet of the tricuspid valve. Reconstruction of the tricuspid valve leaflet by reattachment of chordae and a partial annuloplasty was done with the right atrial wall being replaced using pericardial tissue. The histology of the tumor was compatible with a fibroma, a type not previously reported in this location in the pediatric age group. Twenty-one months following operation, the child was restudied and the catheterization revealed mild to moderate tricuspid regurgitation and no recurrence of the tumor. The child is now 4 years of age and remains asymptomatic with normal growth and development and no evidence of fibromatosis.

Cineangiography↗

Small intestinal atresia and segmental absence of muscle coats.

The case of a newborn infant with small-intestine atresia coexisting with segmental absence of muscle coats leading to perforation and meconium peritonitis is presented. The theories of pathogenesis of the simultaneous occurrence of segmental absence of gut musculature and atresia are briefly reviewed. A possible etiologic role of vascular accident in utero for both conditions is discussed.

Female↗

Ultrastructural demonstration of intracellular bacteria in xanthogranulomatous pyelonephritis.

Xanthogranulomatous pyelonephritis is considered to be an unusual cellular response to bacterial invasion. This assumption is based on circumstantial evidence and experimental studies. In our electron microscopic study of five cases of xanthogranulomatous pyelonephritis demonstrated a stratification of the cellular components, somewhat resembling that described in the experimental lesions. The center of the xanthogranulomas was occupied by purulent exudate. Bacteria were identified mainly in polymorphonuclear leukocytes and extracellularly in four cases in which central area were available for electron microscopic studies. Many bacteria were located in cytoplasmic vacuoles. more peripherally, histiocytes predominated, and their cytoplasm contained numerous lipid droplets with and without limiting membranes and phagolysosomes. The latter contained electron dense, granular, and membranous structures. The outermost layer of the lesion demonstrated macrophages with a decreased number of lipid droplets and larger intralysosomal particles. Lymphocytes, plasma cells, and fibroblasts represented an increasing proportion of the infiltrate in this layer. Our study suggests that xanthogranulomatous pyelonephritis is a bacteria induced process. Its histological appearance may be related to incomplete bacterial degradation and altered host response.

Adult↗

Disseminated ulcerations in allergic eosinophilic gastroenterocolitis.

An infant with allergic eosinophilic gastroenterocolitis is described. The patient presented with vomiting, diarrhea, gastrointestinal bleeding, and failure to thrive. Anemia, hypoproteinemia, and peripheral eosinophilia were also present. Gastrointestinal endoscopy revealed multiple mucosal ulcerations in the stomach, small intestine, and colon. Histological study of the affected areas showed infiltration of the mucosa by eosinophils, increased mucosal IgE plasma cells, and activated intraepithelial lymphocytes. Treatment with corticosteroids resulted in clinical and histological remission.

Child, Preschool↗

Sinusoidal fetal heart rate pattern with vasa previa in twin pregnancy.

A case of vasa previa in twin pregnancy associated with a sinusoidal heart rate was observed. A review of the world literature revealed eight previously reported cases of vasa previa in twins. No first twin survived, and 62.5% of second twins eventually died from partial or complete exsanguination. This is the first reported case of sinusoidal fetal heart rate in association with vasa previa. Continuous fetal monitoring suggested the diagnosis of funic presentation and of fetal bleeding. A high index of suspicion, use of amnioscopy, ability to detect fetal blood in the vaginal pool, continuous fetal heart rate monitoring and ultrasonography may help in reducing the high perinatal mortality associated with vasa previa.

Adult↗

The effects of preservation on microvascular vein grafts in rats.

Segments 15 mm in length were excised from the femoral veins of rats and preserved by refrigeration at 4 C in lactated Ringer's solution for periods up to 21 days. The findings show that veins can be preserved for up to seven days and successfully grafted to recipients. Although there was some success in preserving vein segments for more than seven days, a high rate of thrombosis occurred after implantation in the recipients. It is generally accepted that damaged endothelium causes thrombosis. The light and electron microscopic observations in this study, however, suggest that the condition of the endothelium may not be the only important factor in the patency of small vessels. A thickened and prominent elastic lamina may also play a role in keeping the lumen open.

Animals↗

Chronic relapsing pancreatitis in childhood.

A case of idiopathic, chronic relapsing pancreatitis arising in childhood is presented and compared with the 12 previously reported cases. This entity is a rare cause of severe, recurrent abdominal pain in childhood. The diagnosis is suggested by elevated serum or urine amylase values or pancreatic calcifications. Ultrasound, computerized tomography, or as in this case, endoscopic retrograde cholangiopancreatography can aid in the diagnosis. Surgery yields excellent results.

Adult↗

Cardiac myxoma with chondroid features: a light and electron microscopic study.

The first case of a cardiac myxoma exhibiting chondroid differentiation is described. The tumor showed lacunar spaces around clusters of typical myxoma cells on light microscopy. Ultrastructurally the tumor cells contained abundant glycogen, and the tumor stroma contained proteoglycan granules identical to those seen in the ground substance of cartilage. These findings lend further support to the belief that the primitive mesenchymal cell is the cell of origin in cardiac myxoma.

Cartilage↗

Hydrometrocolpos and polydactyly.

Two cases of hydrometrocolpos and polydactyly in female infants with persistent urogenital sinus are reported. The importance of considering hydrometrocolpos as the cause of an abdominal mass in female infants with polydactyly is stressed. Cytologic examination of the vaginal fluid may help in early diagnosis.

Abnormalities, Multiple↗

Hermansky-Pudlak syndrome with granulomatous colitis.

The Hermansky-Pudlak syndrome consists of tyrosine-positive albinism, a defect in the second phase of platelet aggregation, and widespread accumulation of a ceroidlike pigment in tissue. Pulmonary fibrosis has also been reported. In this paper, we describe two families with documented Hermansky-Pudlak syndrome in which four members, two from each family, developed granulomatous colitis. This adds another disease entity to those associated with this syndrome. We discuss possible connecting links between these disease expressions.

Adolescent↗