Citations

Glottic phonatory parameters have been studied in constant flow models; however, the lung‐thorax system is better viewed as a constant pressure source. Adjusting the driving pressure and recurrent laryngeal nerve stimulation as independent variables, rather than as dependent variables, may provide a more physiologic understanding of laryngeal function and glottic parameters, including subglottic pressure, airflow, fundamental frequency, and glottic area. In three dogs subglottic pressure and airflow were measured in two separate conditions: with constant recurrent laryngeal nerve stimulation and varying driving pressure, and with constant driving pressure and varying recurrent laryngeal nerve stimulation. Videostroboscopic measures on four dogs assessed glottic areas with constant recurrent laryngeal nerve stimulation at different driving pressures. With constant recurrent laryngeal nerve stimulation, increasing driving pressure had no effect on glottic areas, whereas subglottic pressure, fundamental frequency, and airflow increased significantly. However, changes in subglottic pressure were minimal in comparison with changes in driving pressure. At constant driving pressure, increasing recurrent laryngeal nerve stimulation increased subglottic pressure and fundamental frequency and decreased airflow. These findings suggest that during phonation subglottic pressure is primarily dependent on recurrent laryngeal nerve stimulation and laryngeal muscular contraction, but not on lung driving pressure.

Abstract Rationale Pulmonary lymphangioleiomyomatosis is a progressive cystic lung disease that is associated with infiltration of atypical smooth muscle–like cells. Previous descriptions of clinical characteristics of subjects with lymphangioleiomyomatosis have been based on a limited number of patients. Objectives To describe the clinical characteristics of subjects with pulmonary lymphangioleiomyomatosis, both sporadic and tuberous sclerosis–related forms. Methods Over a 3-yr period, from 1998 to 2001, 243 subjects with pulmonary lymphangioleiomyomatosis were enrolled into a national registry; 13 subjects who had already undergone lung transplantation were excluded for the purposes of this report. Measurements and Main Results All 230 subjects were women, aged 18 to 76 yr (mean ± SE, 44.5 ± 0.65 yr). The average age at onset of symptoms was 38.9 ± 0.73 yr and at diagnosis was 41.0 ± 0.65 yr. Tuberous sclerosis complex was present in 14.8% of subjects. Pulmonary manifestations, most commonly spontaneous pneumothorax, were the primary events leading to the diagnosis in 86.5% of cases. Nearly 55% of the subjects were being treated with a progesterone derivative. An obstructive pattern on pulmonary function testing was observed in 57.3% of the subjects, whereas 33.9% had normal spirometric results. Women with tuberous sclerosis–related lymphangioleiomyomatosis were younger and had less impaired lung function compared with those with the sporadic form. Conclusions The age range of women afflicted with pulmonary lymphangioleiomyomatosis is broader than previously appreciated and the degree of pulmonary function can be quite variable, with one-third of subjects having normal spirometry at enrollment into this registry.

Policy has not adequately addressed the unique circumstances of pediatric subspecialties, many of which are facing workforce shortages. Pediatric subspecialties, which we define to include all medical and surgical subspecialties, are discrete disciplines that differ significantly from each other and from adult medicine subspecialties. Concerns about a current shortage of pediatric subspecialists overall are driven by indicators ranging from recruitment difficulties to long wait times for appointments. The future supply of pediatric subspecialists and patient access to pediatric subspecialty care will be affected by a number of key factors or forces for change. We discuss 5 of these factors: changing physician and patient demographics; debt load and lifestyle considerations; competition among providers of subspecialty care; equitable reimbursement for subspecialty services; and policy to regulate physician supply. We also identify issues and strategies that medical and specialty societies, pediatric subspecialists, researchers, child advocates, policy makers, and others should consider in the development of subspecialty-specific workforce-policy agendas.

Abstract Purpose: Women with advanced epithelial ovarian cancer are routinely treated with platinum-paclitaxel chemotherapy following cytoreductive surgery, yet only ∼20% achieve long-term disease-free survival. We hypothesized that differences in gene expression before treatment could distinguish patients with short versus long time to recurrence after administration of platinum-paclitaxel combination chemotherapy. Experimental Design: To test this hypothesis, gene expression profiling of 79 primary surgically resected tumors from women with advanced-stage, high-grade epithelial ovarian cancer was done using cDNA microarrays containing 30,721 genes. Supervised learning algorithms were applied in an effort to develop a binary classifier that could discriminate women at risk for early (≤21 months) versus late (>21 months) relapse after initial chemotherapy. Results: A 14-gene predictive model was developed using a set of training samples (n = 51) and subsequently tested using an independent set of test samples (n = 28). This model correctly predicted the outcome of 24 of the 28 test samples (86% accuracy) with 95% positive predictive value for early relapse. Conclusions: Predictive markers for early recurrence can be identified for platinum-paclitaxel combination chemotherapy in primary ovarian carcinoma. The proposed 14-gene model requires further validation.

AbstractUltrasound and computed tomography have had an enormous impact on the imaging procedures used in the detection of tumors of the parathyroids, pancreas, and adrenals. Ultrasound is now the examination of choice in localizing parathyroid adenomas in the neck prior to cervical exploration or after unsuccessful exploration. Its role as a screening test in patients without biochemical confirmation of hyperparathyroidism awaits further study. Computed tomography is useful in identifying mediastinal parathyroid adenomas in patients who have had unsuccessful neck explorations and islet‐cell tumors of the pancreas if they are sufficiently large (greater than 2 cm). Angiography remains the most accurate method of localizing insulinomas prior to surgery. Computed tomography scanning has become the procedure of choice in localizing adrenal tumors and has sufficient sensitivity to be used as a screening test in patients without biochemical confirmation of an adrenal abnormality.