Cell expansion in plants requires cell wall biosynthesis and rearrangement. During periods of rapid elongation, such as during the growth of etiolated hypocotyls and primary root tips, cells respond dramatically to perturbation of either of these processes. There is growing evidence that this response is initiated by a cell wall integrity-sensing mechanism and dedicated signaling pathway rather than being an inevitable consequence of lost structural integrity. However, the existence of such a pathway in root tissue and its function in a broader developmental context have remained largely unknown. Here, we show that various types of cell wall stress rapidly reduce primary root elongation in Arabidopsis (Arabidopsis thaliana). This response depended on the biosynthesis of 1-aminocyclopropane-1-carboxylic acid (ACC). In agreement with the established ethylene signaling pathway in roots, auxin signaling and superoxide production are required downstream of ACC to reduce elongation. However, this cell wall stress response unexpectedly does not depend on the perception of ethylene. We show that the shortterm effect of ACC on roots is partially independent of its conversion to ethylene or ethylene signaling and that this ACCdependent pathway is also responsible for the rapid reduction of root elongation in response to pathogen-associated molecular patterns. This acute response to internal and external stress thus represents a novel, noncanonical signaling function of ACC.

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This analysis has provided evidence that submuscular placement and textured implants, in addition to other factors, are significant in reducing the incidence of capsular contracture.

Although adrenal tumors detected during pregnancy are extraordinarily rare, the pathophysiologic repercussions of untreated adrenal neoplasms are enormous to both mother and fetus. From our computer-based registry of pregnant patients from 1975 through 1996 (n = 30,246), four cases of adrenal neoplasms associated with pregnancy were identified (0.013%), analyzed, and compared with the current medical literature. Four women ages 36, 29, 22, and 21 years had adrenal neoplasms diagnosed with pregnancy. Patient 1 had an unsuspected pheochromocytoma identified at autopsy. At 27 weeks into her pregnancy the patient suffered a myocardial infarction, and both she and the fetus died. Patient 2 was incidentally found to have adrenal and pancreatic neoplasms on screening abdominal computed tomography for von Hippel-Lindau disease. The study identified a pregnancy. She elected to terminate the pregnancy and underwent resection of both tumors. She died 3 years later of metastatic islet cell cancer. Both of these patients had previously delivered healthy babies, but both pregnancies were complicated by hypertension. Patient 3 had a functional adrenal tumor identified initially by urinary aldosterone studies because of symptoms of severe hypertension, and patient 4 had an adrenal mass diagnosed via ultrasonography at 30 weeks' gestation because of concerns for right-sided pyelonephritis. These two women underwent careful monitoring throughout the remainder of their pregnancies with eventual delivery of healthy babies. Both women later underwent successful operative resection of benign adrenal adenomas. Adrenal neoplasms discovered during pregnancy are rare. The onus, however, is on physicians to consider this diagnosis in pregnant women with hypertension, headaches, or other manifestations of adrenal disorders. Surgical management of identified adrenal lesions is thereafter straightforward. Missing the diagnosis has grave implications for these young women and their fetuses.