Elevated concentrations of the beta-subunit of human chorionic gonadotropin and testosterone in the amniotic fluid of gestations of diabetic mothers

Hyperplasia of testicular Leydig cells and ovarian theca-lutein cells is a common histologic finding in infants of diabetic mothers. The functional correlates of this histologic finding were investigated by measurement of the beta-subunit of human chorionic gonadotropin, testosterone, dihydrotestosterone, androstenedione, estradiol, and estrone in the amniotic fluid compartment of gestations with male and female fetuses in diabetic mothers (N = 34) and control women (N = 34) at term. When compared with those of control subjects, gestations of diabetic mothers had significantly higher amniotic fluid concentrations of the beta-subunit of human chorionic gonadotropin. Gestations with either male or female fetuses in diabetic mothers had significantly higher amniotic fluid testosterone and dihydrotestosterone levels when compared with those of their respective gender controls. In gestations with male fetuses in diabetic mothers there was a significant positive correlation between the beta-subunit of human chorionic gonadotropin and testosterone. There was no significant difference in amniotic fluid androstenedione, estradiol, or estrone levels between the gestations of diabetic mothers and those of control women. These results suggest that the testicular Leydig cell and ovarian theca-lutein cell hyperplasia seen in infants of diabetic mothers is due, in part, to elevated levels of human chorionic gonadotropin and is associated with elevated testosterone and dihydrotestosterone concentrations in the amniotic fluid.     

Choroidal bodies: a new structure in the fourth ventricular choroid plexus of the rat and mouse

Histologic study of the caudal end of the fourth ventricular choroid plexus of the rat and mouse revealed 1-4 small, discrete collections of cells that differed from the surrounding choroidal epithelial cells in appearance. They did not occur in other parts of the choroid plexuses. These choroidal bodies were not affected by a chemical toxin that caused hydropic degeneration of all the epithelial cells in the choroid plexuses. The function, if any, of the choroidal bodies is unknown. They were present in all rats that were studied by serial sections.     

Comparison of two methods used to assess first-ray mobility

Mobility of the first-ray is associated with several common lower extremity disorders. However, the reliability and validity of clinical measurement remains unclear. In this study we examined first-ray mobility by using one hand to stabilize the lesser metatarsals while the clinician's other hand applied a displacement force to the head of the first metatarsal. The amount of mobility was graded as stiff, normal or hypermobile. We then used a well-validated mechanical device to perform similar tests and assessed validity, intrarater reliability and interrater reliability. Three clinicians having varied levels of experience graded first-ray mobility on 15 subjects. A separate investigator measured dorsal mobility with a mechanical device. Both methods of testing were repeated to assess measurement reliability. Reliability was estimated by kappa (K) statistics. Spearman correlation assessed the relationship between mobility graded manually and dorsal mobility measured by device. Manual examination intrarater K values ranged from 0.50 to 0.85, and interrater agreement from 0.09 to 0.16. Manual grading was not related (r = -0.21) to the absolute measure of total dorsal mobility made by device. This brings into question the validity and reliability of manual estimates of first-ray mobility.     

Neuropsychological function in mild hyperphenylalaninemia

Whether specific cognitive deficits related to frontal-lobe dysfunction that have been reported in individuals with phenylketonuria (PKU) are also characteristic of mild hyperphenylalaninemia (MHP) was investigated. Tests of executive function and control tasks not assessing executive function were administered to a group of individuals with MHP and a group without MHP, similar in age, gender, and IQ. Tests of academic skills and behavior-rating questionnaires were also administered to the group with MHP. No group differences were found for any measure, suggesting that the mild elevations of phenylalanine in individuals with MHP are not sufficient to produce behavioral and cognitive impairments characteristic of PKU.     

Nurses' perceived barriers to the implementation of a Fall Prevention Clinical Practice Guideline in Singapore hospitals

Background  

Theories of behavior change indicate that an analysis of barriers to change is helpful when trying to influence professional practice. The aim of this study was to assess the perceived barriers to practice change by eliciting nurses' opinions with regard to barriers to, and facilitators of, implementation of a Fall Prevention clinical practice guideline in five acute care hospitals in Singapore.     

Prevention of lithium nephrotoxicity in a novel one-hour model in rats

It is well established that lithium can cause morphologically visible damage to the kidneys of humans and animals. Although the clinical significance of its nephrotoxicity is debatable, it would be desirable to find a method to prevent lithium’s effect on the kidneys. Toward this end, we have developed a novel method for producing nephrotoxicity that will be useful for research on prevention. A single, large, toxic dose of lithium chloride (LiCl) caused necrosis of the distal convoluted tubules, which was visible by light microscopy in 30 min, had fully developed in 1 h, and had disappeared by the next day. The lesions were seen after IP or IV injections of fasted rats of three different strains. Equivalent doses of NaCl, KCl, MgCl₂ and combinations thereof had no such effect, nor did they inhibit nephrotoxicity when incorporated into the LiCl solution. However, relatively small doses of LiCl injected by any route 3 or 24 h beforehand prevented the nephrotoxicity. The mechanism of prevention is not known, but it does not involve reduction of lithium levels in the kidneys. Received: 30 July 1997/Final version: 18 November 1997