A novel protein interacts with the major transforming growth factor-beta responsive element in the plasminogen activator inhibitor type-1 gene.

Multiple transforming growth factor-beta (TGF-beta) responsive elements have been identified within the 5'-flanking region of the plasminogen activator inhibitor type-1 (PAI-1) gene. This study was designed to characterize the major TGF-beta responsive element (-804 to -546). DNA footprint assays showed that the region of protein contact (-726 to -703) did not include consensus sequences for any known transacting factors. The results of UV cross-linking and Southwestern blot experiments showed that a protein of M(r) 100,000 specifically binds to the TGF-beta responsive element and that this protein undergoes post-transcriptional activation within 5 min after stimulation of Hep G2 cells by TGF-beta resulting in a marked increase in affinity for the target DNA sequence. These results show that stimulation of Hep G2 cells with TGF-beta increases the affinity of a novel 100-kDa protein for the major TGF-beta responsive element within the PAI-1 gene.

Upper abdominal lymph nodes: criteria for normal size determined with CT.

Reports of the upper limits of normal for lymph node size at abdominal computed tomography have varied from 6 to 20 mm. Establishment of an upper limit for node size by specific location, analogous to that which has been reported for mediastinal lymph nodes, was sought. Short-axis diameters of the lymph nodes were measured in 130 patients who were not likely to have enlarged abdominal lymph nodes. Seven locations were defined, and the largest nodal measurement for each was recorded. Histographic analysis and nonparametric statistical methods were used to determine threshold values for the maximum node size in each region. The upper limits of normal by location were as follows: retrocrural space, 6 mm; paracardiac, 8 mm; gastrohepatic ligament, 8 mm; upper paraaortic region, 9 mm; portacaval space, 10 mm; porta hepatis, 7 mm; and lower paraaortic region, 11 mm. Lower paraaortic lymph nodes larger than 11 mm by short-axis measurement are abnormal. In other locations, nodes smaller than 1 cm may be abnormal if the determined thresholds are exceeded.

Seminal vesicle cysts: association with adult polycystic kidney disease.

Adult polycystic kidney disease (APKD) is associated with cyst formation in the kidney, liver, pancreas, esophagus, ovary, uterus, and brain. Four patients with APKD (aged 45-65 years) with computed tomographic evidence of seminal vesicle cysts are described. All seminal vesicles contained cystic masses with attenuation values of 0-30 HU. Seminal vesicle thickness was 3-4 cm (normal, 1.5 cm). High-attenuation walls separated the cysts, which were 3-35 mm in diameter. All patients had typical renal stigmata of APKD. None had cysts elsewhere, except one patient with hepatic cysts. Postmortem examination in one patient confirmed the seminal vesicle cysts as well as APKD. It is likely that a basement membrane defect allows cyst formation in multiple organs, presumably including the seminal vesicles. Because of the association of seminal vesicle cysts with ipsilateral urogenital anomalies, and because only 60% of patients with APKD have a relevant familial history, the kidneys of patients with cross-sectional imaging evidence of seminal vesicle cysts should also be studied.

Coronary vasospasm secondary to labetalol in a patient with aortic dissection.

A 66-year-old hypertensive woman presented with epigastric and scapular pain on the basis of type 3 aortic dissection. Appropriate therapy with a combined alpha-adrenergic and beta-adrenergic antagonist agent prevented further ongoing dissection and amelioration of symptoms. On day 5, an episode of coronary vasospasm occurred presumably due to beta-blockade with unopposed alpha-adrenergic activity.

Computed tomographic evaluation of intrathoracic thyroid malignancy.

As only a few cases of intrathoracic thyroid malignancy with computed tomographic (CT) examination have been described, we reviewed the CT examinations of three patients with primary and five patients with recurrent thyroid malignancy involving the thorax. Irregular border of the thyroid mass, extension of tumor mass into mediastinal fat or chest wall, or lymphadenopathy suggested the malignant nature of the primary tumor. CT examination in recurrent disease demonstrated mediastinal, hilar and retrocrural adenopathy, compression of major vessels with collateral flow, pulmonary and bony metastases. CT was of value both in identifying the extent of disease and documenting response to treatment.

Pericardial tamponade associated with pacemaker catheter manipulation.

Three patients developed cardiac tamponade following postpacemaker catheter manipulation. Although regarded as a rare complication, this entity has to be recognized immediately on clinical grounds and confirmed by echocardiography. Prompt recognition and urgent pericardial drainage is lifesaving in this acute cardiac emergency.

Meningococcaemia complicated by myocarditis. A report of 2 cases.

Two cases of myocarditis complicating meningococcal septicaemia are presented. Neisseria meningitidis infection with bacteraemia is a common entity but the important complication of myocarditis has not often been described. The autopsy findings in 1 of the 2 patients described further illustrates the significance of myocarditis. The pathology, clinical presentation and management of this complication are briefly discussed.

Case report: CT of a duodenal paraganglioma.

Paraganglioma is a neoplasm of neuroectodermal origin that occurs rarely in the bowel. This case report illustrates the previously undescribed CT appearance of a duodenal paraganglioma. An intensely enhancing mass in the region of the pancreatic head was found. The intense enhancement ruled out adenocarcinoma and focal pancreatitis. An islet cell tumor of the pancreas was the major differential diagnostic consideration.

Computed tomography of vena caval anomalies with embryologic correlation.

Vena caval and left renal vein anomalies are not uncommon and are easily identified by CT, usually in an incidental fashion. A simple classification of these anomalies is presented (Table I). These anomalies become significant only when they are mistaken for pathologic masses or when one is planning surgical or radiologic vascular procedures. Detailed knowledge of these anomalies, in conjunction with the use of dynamic bolus CT, will permit easy diagnosis in nearly all cases.

CT of renal cell carcinoma in patients on chronic hemodialysis.

The occurrence rate of renal cell carcinoma is significantly higher in the native kidneys of patients undergoing chronic hemodialysis than in kidneys of normal subjects. These carcinomas may be difficult to detect because these kidneys tend to be small and distorted owing to acquired cystic disease. Four cases of renal cell carcinoma detected by CT are presented (three in patients undergoing chronic hemodialysis, and one in a patient with a functioning transplant who had history of dialysis). All kidneys had extensive acquired cystic disease. In two cases, contrast-enhanced scans showed a solid lesion of lower density than the kidney. In another case, in which IV contrast material could not be given, the mass was of higher density than the kidney and retroperitoneal lymphadenopathy was present. In the fourth case, no distinct solid mass could be identified. The only sign of malignancy in this case was extensive lymphadenopathy. Whenever CT examination of the abdomen is performed in a patient undergoing chronic hemodialysis, the kidneys must be evaluated carefully because of the increased frequency of renal cell carcinoma. In a few cases, a distinct solid lesion may not be apparent or may be subtle owing to distortion of renal anatomy by acquired cystic disease.

Small-cell bronchogenic carcinoma: CT evaluation.

CT examinations in 37 patients with proved small-cell bronchogenic carcinoma studied before treatment were reviewed. The distribution of lymphadenopathy in the mediastinal compartments designated by the American Thoracic Society was assessed. The frequency of lymph node enlargement was right hilum (43%), left hilum (49%), one or both hila (84%), right upper paratracheal (32%), right lower paratracheal (54%), right tracheobronchial (65%), left upper paratracheal (14%), left lower paratracheal (38%), left peribronchial (35%), paraesophageal (14%), anterior mediastinum (24%), and subcarinal (65%). We also assessed the frequency of additional findings including pleural effusion (38%), pericardial thickening (38%), displacement or narrowing of either the tracheobronchial tree (68%) or major vessels (68%), and hepatic masses (24%). Mediastinal involvement was present in 92% of cases, as compared with 13% reported in a large series based on conventional radiography. These data show the spectrum of intrathoracic CT findings in proved, untreated cases of small-cell bronchogenic carcinoma.

Multiple pulmonary cavities--an unusual complication of Pneumocystis carinii pneumonia.

Cavitation is a most unusual radiological feature of Pneumocystis carinii pneumonia (PCP). Autopsy evidence of cavities in PCP is poorly documented. We describe a case of fatal PCP occurring in a patient with the acquired immune deficiency syndrome; the PCP was associated with radiological as well as autopsy evidence of large intrapulmonary cavities. These cavities are ascribed to Pneumocystis carinii infection, since other possible causes were excluded.

Abdominal lymphadenopathy in benign diseases: CT detection.

A review of 2,100 consecutive computed tomographic (CT) examinations yielded 160 cases of abdominal lymphadenopathy, of which nine (6%) were secondary to benign diseases. Contrary to previous reports, size, location, contour, density, relationship to the aorta, and presence of mass effect were not helpful in distinguishing benign from malignant lymphadenopathy. In some cases, ancillary CT findings, conventional radiographs, and clinical setting may suggest a specific benign entity. Benign processes should be considered in the differential diagnosis of abdominal lymphadenopathy in the appropriate clinical setting, particularly if the patient does not have a known carcinoma.