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Biomedical subjects

M A Stull

Publications and source records attributed to M A Stull.

At least 19 recordsLinked to original sources
PubMed2000

The insulin-like growth factors (IGFs) and IGF binding proteins in postnatal development of murine mammary glands.

The insulin-like growth factors are mitogens and survival factors for normal mammary epithelial cells in vitro. Data reviewed here demonstrate that mRNAs for IGF-I and IGF-II, the IGF type I receptor and the IGFBPs are expressed locally in mammary tissue during pubertal and pregnancy-induced growth and differentiation of murine mammary glands. IGF-I, IGF-II and the IGF-IR were expressed in terminal end buds (TEBs) in virgin glands during ductal growth. In addition, IGF-II and IGF-IR mRNAs were expressed in ductal and alveolar epithelium in glands throughout postnatal development. Consistent with these results, IGF-I promoted ductal growth and proliferation in mouse mammary glands in organ culture. In addition to endogenous expression of the IGFs and IGF-IR, the IGFBPs showed a varied pattern of expression in mammary tissue during postnatal development. For example, IGFBP-3 and -5 mRNAs were expressed in TEBs and ducts while IGFBP-2 and -4 mRNAs were expressed in stromal cells immediately surrounding the epithelium. These results support a role for the IGFs and IGFBPs as local mediators of postnatal mammary gland growth and differentiation.

Animals↗
PubMed1999

Sentinel lymphadenectomy for breast cancer: experience with 180 consecutive patients: efficacy of filtered technetium 99m sulphur colloid with overnight migration time.

BACKGROUND: Axillary node status remains the most important prognostic indicator of survival in breast cancer patients. Only 25% to 35% of patients having standard level I/II axillary dissection have involved nodes, yet all accept the potential for morbidity after the operation. This study was conducted to assess whether status of the sentinel node(s) was an accurate predictor of the presence of metastatic disease in axillary or internal mammary nodes. STUDY DESIGN: In 180 patients, technetium 99m sulphur colloid was injected in a 4-quadrant peritumoral distribution. During the first phase of the study, 72 patients had sentinel node excision followed by a level I/II axillary dissection. During the second phase of the study, 108 patients had sentinel node excision and only those with positive nodes had completion axillary dissection. Nodes were examined after formalin fixation by taking 10 sections at 20-microm intervals and staining with hematoxylin-eosin. RESULTS: Sentinel nodes were found in 162 (90%) of 180 patients. The mean number of sentinel nodes examined was 3.1. Of the 162 patients with successful lymphatic mapping, positive sentinel nodes were found in 44 (27%). In 23 (66%) of 35 patients with positive sentinel nodes who had a completion level I/II axillary dissection, the sentinel nodes were the only positive nodes. The concurrent negative predictive value was 4% in the first 72 patients who had completion axillary dissection after sentinel node excision, and 2% for the entire series. With evolution of technique, identification of sentinel nodes with radiolabeled colloid was successful in 97% of the last 100 patients. CONCLUSIONS: Because the concurrent negative predictive value was low, sentinel node excision appeared to accurately identify node status, potentially avoiding the need for standard level I/II axillary dissection in sentinel node-negative patients.

Axilla↗
PubMed1998

Percutaneous needle biopsy of mediastinal masses using a computed tomography-guided extrapleural approach.

This study was conducted to determine the reliability of mediastinal biopsy using a computed tomography-guided extrapleural approach. Twenty patients (16 men and 4 women) between the ages of 30 to 79 years underwent 22 percutaneous biopsies. The sampled masses ranged in size from 1.6 to 8 cm. A coaxial 17-gauge needle system was advanced into the fascia subjacent to the parietal pleura. An extrapleural fluid collection was created using a 20%/80% ratio of 1% lidocaine and normal saline. The blunt cannula was then advanced through the fluid to the edge of the lesion, and core or cytologic specimens were obtained. A diagnosis was obtained in 18 of 20 patients (90%). There were 10 malignant and 8 benign diagnoses. Complications included pneumothorax (1), vasovagal reactions (1), intercostal neuritis (1), and transient Homer's syndrome (1). In this series, both a high diagnostic yield as well as a low complication rate were obtained.

Adult↗
PubMed1993

Bronchial carcinoid presenting as refractory asthma.

Bronchial carcinoids are low-grade malignant neoplasms that usually occur in the central airways. The central endobronchial location typically results in symptoms of bronchial obstruction. Infrequently, asthma-like symptoms may be produced by endobronchial tumors. The diagnosis of bronchial carcinoid is often made after months of unsuccessful treatment for more common respiratory conditions.

Adult↗
PubMed1992

Langerhans cell histiocytosis of bone.

Langerhans cell histiocytosis (LCH), previously called histiocytosis X, refers to a spectrum of disease characterized by idiopathic proliferation of histiocytes producing focal or systemic manifestations. Causes and pathogenesis remain unclear. However, recent studies suggest abnormal immune regulation as an important factor. The three classic syndromes may have considerable clinical overlap: eosinophilic granuloma, in which the disease is limited to bone in patients usually 5-15 years old; Hand-Schüller-Christian disease, characterized by multifocal bone lesions and extraskeletal involvement of the reticuloendothelial system (RES) usually seen in children 1-5 years old; and Letterer-Siwe disease, in which there is disseminated involvement of the RES with a fulminant clinical course in children less than 2 years old. Osseous involvement is typically in the flat bones, with lesions of the skull, pelvis, and ribs accounting for more than half of all lesions. About 30% of lesions are in long bones. Radiographic appearance of osseous LCH depends on site of involvement and phase of the disease. Early lesions appear aggressive with poorly defined margins and lamellated periosteal reaction. Late lesions appear well defined and may show sclerotic margins and expanded remodeled appearance.

Bone Diseases↗
PubMed1991

Magnetic resonance appearance of peripheral nerve sheath tumors.

Magnetic resonance imaging (MRI) was used to evaluate 22 histologically proven peripheral nerve sheath tumors, approximately two-thirds of which arose in the lower extremity. The histologic distribution was as follows: 12 schwannomas, 7 neurofibromas, and 3 malignant peripheral nerve sheath tumors (2 of which occurred in patients with neurofibromatosis). Most lesions demonstrated an intermediate to moderately bright signal on T1-weighted images and were minimally inhomogeneous. All lesions were moderately bright on proton-density-weighted images and bright on T2-weighted images, again with variable inhomogeneity. The extent of the tumor was best assessed on proton-density- and T2-weighted images. Smooth margins were noted in 19 lesions. Of the 3 remaining lesions, 2 were malignant (but had been subjected to biopsy prior to MRI), and the other lesion was a plexiform neurofibroma. MRI accurately determined the relationship between the lesion and the adjacent neurovascular structures and muscles, thereby assisting surgical management. On MRI, 5 lesions demonstrated coexistent subtle muscle atrophy along the longitudinal axis of surrounding or distally innervated musculature. This latter finding, together with the presence of a tumor in the vicinity of a large nerve trunk, suggests a peripheral nerve sheath neoplasm.

Adult↗
PubMed1991

Osteoid osteoma.

Osteoid osteoma is a benign skeletal neoplasm composed of osteoid and woven bone that rarely exceeds 1.5 cm in greatest dimension. The lesion is most commonly located in the cortex of long bones where it is associated with dense, fusiform, reactive sclerosis. Less often, it may be cancellous, where reactive osteosclerosis is usually less intense and may be distant from the lesion. Cancellous lesions are frequently intraarticular (most often in the hip) and may be associated with synovitis and joint effusion. Rarely, osteoid osteomas occur in a subperiosteal location. Patients are usually young, and there is a strong male predominance. Pain is the most common symptom. Radiographs of patients with cortical osteoid osteoma are often diagnostic. Intraarticular lesions, however, may be subtle, and scintigraphy may be required to locate the lesion for subsequent computed tomography (CT). CT is useful to identify and precisely locate the lesion and to provide guidance for percutaneous localization or treatment.

Adolescent↗
PubMed1990

Magnetic resonance imaging of peripheral soft tissue hemangiomas.

Ten patients with soft tissue hemangiomas outside the central nervous system were studied with MR imaging. Eight patients were studied at 1.5 Tesla (T) with T1-weighted and triple echo T2-weighted sequences. Two additional patients were imaged on a 0.5-T system. The MR images were correlated with images from other modalities. Histologic diagnosis was obtained in all cases. It was found that prolonged T2-weighted imaging together with standard spin echo T1 and T2 pulse sequences is a good substitute for contrast-enhanced CT and arteriographic evaluation of soft tissue hemangiomas.

Adolescent↗
PubMed1990

Paget's disease of the patella.

Five patients with Paget's disease involving the patella were evaluated for the following radiographic features: trabecular pattern, cortical integrity, density, and size of the affected patella. Radiographic appearances consisted of minimal trabecular coarsening in the patella of nearly normal size and progressed to considerable cortical thickening and osteoblastic remodeling in a dramatically enlarged patella. The radiologic features of Paget's disease of the patella are distinctive and should obviate biopsy.

Adult↗
PubMed1990

Case report 610: Amyloid arthropathy of the left ankle.

In summary, a case of amyloid arthropathy of the left ankle in a 64-year-old patient with multiple myeloma is presented. The asymmetric presentation and site of deposition in the ankle were taken to be unusual. Involvement of both hips and the right shoulder was also suspected on subsequent evaluation. The patient's history and MR studies were essential in establishing the preoperative diagnosis. The extent of involvement, destruction of underlying cartilage, associated effusion and tenosynovitis were optimally defined by the MR images. The MR images also provided preoperative guidance in determining the approach and optimum site of biopsy.

Amyloidosis↗
PubMed1990

Primary Ewing sarcoma of rib.

Ewing sarcoma is a relatively common, highly malignant bone tumor that typically occurs in adolescents and young adults aged 10-25 years. Our archives contain 328 cases of histologically proved and radiologically correlated Ewing sarcoma collected in consultation over 40 years. From this series, we identified 34 lesions (10%) arising in ribs. Radiographically, the affected rib was predominantly lytic in most (82%) cases, but mixed lytic-sclerotic (9%) and even predominantly sclerotic (9%) patterns were also encountered. The affected rib was "expanded" in 35% of cases, although the contour change was usually mild. Abnormalities of the affected ipsilateral hemithorax varied from subtle, isolated rib involvement to solitary rib involvement accompanied by complete opacification of the hemithorax. We describe the spectrum of radiologic findings of primary Ewing sarcoma of rib, augmented where appropriate by accompanying pathologic material.

Adolescent↗