The correlation of the vasopressin- and oxytocin-producing activities of different nuclei in the hypothalamo-hypophyseal neurosecretory system]

Radioiodine long has proven to be a safe and effective treatment for thyroid disease. Nonetheless, persisting concerns regarding radiogenic stochastic risks (e.g., carcinogenesis) to patients, their families, and the general public have led regulators to establish criteria for release of 131I-containing patients from medical confinement, with limits ranging from as low as 2 mCi in some parts of Europe to as high as 30 mCi in the United States. To optimize clinical efficacy and cost-effectiveness of 131I therapy, such regulations should be based on logical dosimetric considerations. The thyroidal absorbed dose, proportional to maximum uptake and effective half-life and inversely proportional to mass, is typically approximately 1,500 rad/mCi of 131I administered to a euthyroid adult (based on a thyroid maximum uptake of 25%, effective half-life equivalent to the physical half-life of 131I (8.04 days), and mass of 20 g). As thyroid uptake increases from 0% to 100%, extrathyroidal absorbed doses range from a minimum of 0.15 to 0.5 rad/mCi for breast and gonads to a maximum of 1.5 to 2 rad/mCi for stomach and salivary glands; the absorbed doses of the urinary bladder wall, in contrast, decrease with increasing thyroid uptake, from 2 to 0.6 rad/mCi. In hyperthyroid patients (approximately 15%) with a small iodine pool (so-called small patients), the short effective half-life of radioiodine in the thyroid and high serum concentrations of long-lived protein-bound 131I result in a standard 7,000-rad absorbed dose for treatment of Graves' disease requiring an administered activity of 28 mCi of 131I and yielding a prohibitively high blood absorbed dose of 150 rad. Importantly, once the fetal thyroid begins to function and accumulate radioiodine at a gestational age of 10-12 weeks, fetal thyroid absorbed doses as large as 5,000 rad/mCi of 131I administered to the mother can result. Thus, pregnancy is an absolute contraindication to administration of 131I because of the risk of radiogenic cretinism. Based on actual measurements of thyroid activity and of external absorbed dose, the total thyroid and mean extrathyroidal absorbed doses to adult family members from immediately released 131I-treated patients are approximately 0.01 and approximately 0.02 rad/mCi administered, respectively, yielding an effective dose of approximately 0.02 rem/mCi. A maximum permissible effective dose of 0.5 rem for adults therefore is consistent with a release criterion of 30 mCi of retained 131I. Lower-activity release criteria therefore may be unnecessarily restrictive.     

Securing urethral catheters in patients undergoing urethrovesical anastomosis

OBJECTIVE: Securing urethral catheters for the optimal healing of and prevention of extravasation at the urethrovesical anastomosis. METHOD: This article describes the technique that we use to help secure Foley catheters or replace them if necessary. CONCLUSION: In the rare patients where disruption of the anastomosis or loss of the catheter prematurely takes place, the nylon suture can be used to replace the catheter without jeopardizing the anastomotic line.     

Reliability of phase-velocity measurements of tibial bone

BACKGROUND AND PURPOSE: The Bone Stiffness Measurement Device-Swing is capable of measuring the propagation velocity of flexural waves in human tibial bone, which relates to bending stiffness. If the interrater and intrarater reliability of measurements obtained with the device are established, it can be used with confidence in assessing changes in bone. The purposes of this study were to detect potential sources of measurement error and to establish the interrater and intrarater reliability of measurements taken with the device. SUBJECTS AND METHODS: In the first part of the study, a random-effects design was used to obtain phase-velocity measurements in subjects without known orthopedic or neurological impairments. The second part of the study consisted of possible applications of the device with mixed designs on subjects with spinal cord injuries. By means of generalizability theory, multiple sources of error (eg, occasion, clinician, repetition) were estimated. For the clinical trial, 17 persons with spinal cord injuries not older than 5 weeks were tested. RESULTS: The standard error of measurement (SEM) for intrarater reliability measurements ranged from 7.3 to 9.8 m x s(-1) . The SEMs for interrater reliability measurements ranged from 5.7 to 9.5 m x s(-1). The SEMs for measurements obtained by a single clinician in a clinical population ranged from 11.9 to 39.7 m x s(-1). CONCLUSION AND DISCUSSION: The reproducibility of measurements obtained with the device is suitably high for the device to be used for evaluation in clinical and research settings.     

Effect of tylosin tartrate on humoral immune responses in chickens

This article examines the 50-year struggle of osteopathic physicians to gain entry into the US Military Medical Corps on the same basis as allopathic physicians. The author explores various arguments put forth by both physician groups, as well as those arguments presented by the respective surgeons general and relevant government officials.     

Ambulatory urodynamics

Ambulatory monitoring of lower and upper urinary tract continues to develop. The addition of electronic urine-loss measurements to indicate the exact time-related loss is an important new feature. In the near future, quantitative urine-loss measurements will become available. The additional possibility of plugging in a flowmeter completes the technique with respect to pressure-flow analysis. At present, however, ambulatory urodynamics is still confined to specialized urodynamic centers. Ambulatory urodynamic monitoring has shown that de-novo detrusor instability after a suspension operation is frequently missed as a preoperative diagnosis of detrusor overactivity. The first steps are being taken toward giving a quantitative analysis of detrusor activity during the filling phase. This justifies a more widespread use of this ambulatory monitoring.     

Expression of beta 1 integrins changes during transformation of avian lens epithelium to mesenchyme in collagen gels

Remarkably, a number of definitive epithelia, such as that of the anterior lens, give rise when suspended within 3D gels of type I collagen, to elongate, bipolar shaped cells that exhibit the ultrastructure, polarity, and migratory ability of mesenchymal cells. They begin producing type I collagen and stop producing crystallins, type IV collagen, and laminin. Here, we investigated changes in beta 1 integrins and their extracellular matrix (ECM) ligands during this transdifferentiation. The former free surface of the lens epithelium that is now in contact with collagen begins within a day to stain intensely for beta 1 and it is this surface rather than the surface facing the basement membrane that gives rise to mesenchymal cells. Immunoprecipitation experiments reveal a large increase in the beta 1 integrin subunit on mesenchymal cells as compared to the epithelium of origin. The alpha 5 integrin subunit, which is barely detectable in the lens, increases in the mesenchymal cells and alpha 3 continues to be expressed at about the same level as in the epithelium. alpha 6, the epithelial integrin subunit, and laminin, its ECM ligand, are not detected immunohistochemically or biochemically in the mesenchyme. Rather, the mesenchymal cells secrete abundant fibronectin, the major ECM ligand for alpha 5 beta 1. RGD peptides do not inhibit the transformation but antibodies to beta 1 do perturb the emigration of mesenchymal cells from the lens apical surface. We conclude that the beta 1 integrins newly expressed on the apical epithelial surface interact with the surrounding 3D collagen gel to help bring about this unusual epithelial-mesenchymal transition.