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R Fresco

Publications and source records attributed to R Fresco.

60 records · Page 4Linked to original sources

Mixed epithelial and stromal tumor of the kidney: preliminary immunohistochemical and electron microscopic studies of the epithelial component.

Mixed epithelial and stromal tumor of the kidney is a rare biphasic tumor composed of cysts and tubules embedded in the spindle cell stroma. Although the histogenesis of this tumor is unknown, it has been proposed that both components of the tumor, i.e., stromal and epithelial, are neoplastic. The authors report preliminary immunohistochemical and electron microscopic studies of the epithelial component from one case of a typical, benign, mixed epithelial, and stromal tumor of the kidney. In this study, some tubules showed positivity for proximal, while others showed positivity for distal, nephron immunomarkers. By electron microscopy, some tubules had features of proximal tubular epithelium, while other tubules had features of the loop of Henle (thin segments). The authors believe that in a benign tumor such morphologic heterogeneity is inconsistent with neoplastic proliferation. Therefore, they postulate that in mixed epithelial and stromal tumor of the kidney the tubules are entrapped rather than neoplastic. Additional studies are needed to address this issue and electron microscopy should play a significant role in this process.

Adult↗

Effect of wood combustion smoke inhalation on angiotensin-1-converting enzyme in the dog.

One lung of each dog was exposed to smoke from burning pine wood, while the other was subjected to acute hypoxia. Angiotensin-1-converting enzyme (ACE) activity in biopsied tissue of the smoke-exposed lung was markedly increased immediately after the injury and even higher 30 minutes later. No change in ACE activity was observed in the hypoxic contralateral lung. Serum ACE activity did not change significantly following anesthesia and before smoke inhalation. Serum aldosterone and cortisol levels increased at this juncture. Smoke inhalation caused intra-alveolar hemorrhages and edema. Pulmonary and systolic, diastolic and mean pressures, pulmonary capillary, wedge pressure, cardiac output and systemic and pulmonary arteriolar resistances remained unchanged throughout the experiment. The changes of ACE activity are presumably a direct effect of smoke inhalation. They are seen as an early response of the lung endothelial cells to many types of injury (chronic hypoxia, bleomycin or monocrotaline administration) and may represent an important step in the development of the organ's response to the injury.

Aldosterone↗