Biomedical subjects

T E Muir

Publications and source records attributed to T E Muir.

4 recordsLinked to original sources

PubMed2001

Metanephric adenoma, nephrogenic rests, and Wilms' tumor: a histologic and immunophenotypic comparison.

Metanephric adenoma (MA) is a renal tumor that is generally detected in adults and occasionally in children. These tumors usually behave in a benign fashion. Although the histogenesis of MA is unclear, a morphologic similarity to Wilms' tumor (WT) complex exists. Six cases of MA, five cases of childhood WT (CWT), two cases of adult WT (AWT), and four cases of treated MWT and/or nephrogenic rests (MWT/NR), with paraffin blocks available for use, were retrieved from the surgical pathology files of the Mayo Clinic. Clinical information was extracted from the medical record. Immunoperoxidase stains for WT1, AE1, CK7, CD57, CD56, and desmin were performed on paraffin sections from all cases. All six cases of MA were strongly and diffusely positive with antibodies to WT1 and CD57 and focally positive with antibodies to CK7. Three cases showed focal faint staining in <5% of the cells with keratin AE1. Stains for CD56 and desmin were negative. All seven cases of WT, including five CWT and two AWT, were strongly and diffusely positive with WT1 in the blastema and epithelium but showed only weak focal positivity in stromal cells. Six cases were diffusely positive for CD56 and one case showed focal positivity. Keratin AE1 was positive in one case of AWT and focally positive in the other AWT. The blastema of all cases of WT were negative for desmin, CK7, and CD57, although staining for keratin AE1, CD56, and CD57 was seen in maturing tubules of CWT cases. Of the five CWT cases, two had associated NR and two showed maturing WT after treatment. The areas of NR and maturing WT were histologically similar to MA and were composed of small tubules with uniform nuclei with no mitotic activity, scant cytoplasm, and focal calcifications. All four cases of maturing WT/NR were positive for WT1 and focally positive for CD57, CK7, and AE1. Stains for CD56 and desmin were negative except in foci of residual blastema, which stained for CD56 but lacked CD57 and CK7 staining. Five cases each of renal cell carcinoma, papillary renal cell carcinoma, and oncocytoma were negative for WT1. Two of five cases of chromophobe carcinoma showed very weak staining present in <10% of tumor nuclei. Metanephric adenoma is histogenetically related to WT and is morphologically and immunophenotypically identical to maturing WT and nephrogenic rests.

Adenoma↗

PubMed1998

Micronodular pneumocyte hyperplasia.

Tuberous sclerosis complex (TSC) is an autosomal-dominant disorder characterized by mental retardation, seizures, and central nervous system and visceral hamartomas. Pulmonary involvement manifesting as lymphangioleiomyomatosis (LAM) occurs in 1% of patients (all women) with TSC. Micronodular pneumocyte hyperplasia also has been described as a rare pulmonary manifestation of TSC. We report 14 patients with micronodular pneumocyte hyperplasia (MNPH). The patients ranged in age from 23 to 57 years (mean 37.5). There were 12 women and 2 men. Nine of the patients (one man and eight women) had documented clinical manifestations of TSC: seven with LAM, two without LAM (including one man). Of the five patients who did not have TSC, three had LAM and two did not (including one man). Histologically, all 14 cases demonstrated multiple well-demarcated nodules usually measuring up to 8 mm in size, but most were 1-3 mm. The nodules were produced by a proliferation of enlarged cytologically benign type II pneumocytes, with an associated increase in alveolar macrophages and interstitial reticulin. Immunoperoxidase studies showed the type II pneumocytes within lesions to be reactive with antibodies to cytokeratin (four of four), epithelial membrane antigen (EMA) (five of five), and surfactant apoprotein B (8 of 10). HMB-45 was negative in the MNPH lesions in all nine cases studied. Follow-up was available in 9 of 10 living patients and ranged from 1 to 14 years (mean 6 years). Nine patients are alive; six are clinically stable and three have repeated pneumothoraces related to LAM. Four patients have died. None of the deaths were attributable to MNPH. MNPH appears to be a hamartomatous proliferation occurring most frequently in patients with tuberous sclerosis, is separable from and not a manifestation of LAM, has been observed to occur in men, and, like other hamartomas of tuberous sclerosis, does not appear to possess malignant potential.

Adult↗

PubMed1997

Organizing diffuse alveolar damage associated with progressive systemic sclerosis.

Diffuse alveolar damage (DAD) is a relatively nonspecific pattern of acute lung injury that can be observed in a wide range of clinical circumstances. DAD has often been recognized in association with various connective tissue diseases; however, to our knowledge, it has not been previously reported in the setting of progressive systemic sclerosis. Herein we describe two patients with established diagnoses of progressive systemic sclerosis who had development of the acute respiratory distress syndrome. Open-lung biopsy specimens from both patients showed a histologic pattern of DAD with no identifiable cause other than their progressive systemic sclerosis. Our results suggest that DAD should be added to the list of pleuropulmonary complications of progressive systemic sclerosis.

Aged↗

PubMed1983

The retention of vital submucosal roots under immediate dentures: a surgical procedure.

An approach to soft tissue management and surgical crown/root sectioning for submucosal vital root retention has been presented. Attention to detail during soft tissue reflection, tooth sectioning, and the relaxing of attached mucogingival tissues is very important. Adequate healthy soft tissue is necessary for proper suturing over the retained roots. Postoperative complications are reduced by placement of well-fitted prostheses. Clinical evaluation of this technique has proved it to be highly successful.

Alveolar Process↗