Superior collicular projection to intralaminar thalamus in rat

The superior collicular (SC) cells which project to the intralaminar thalamus (IT; nuclei centralis lateralis, CL; paracentralis, PC; parafascicularis, Pf) in the rat were identified by means of retrograde transport of wheatgerm agglutinin conjugated horseradish peroxidase (WGA-HRP). SC-IT cells were located throughout the mediolateral and rostrocaudal extents of the tectum ipsilateral to the thalamic injection. In this SC, they had a primarily bilaminar distribution in the lower one-half of the stratum griseum intermediale (SGI) and upper portion of the stratum griseum profundum (SGP). In these laminae, SC-IT cells were arranged in clusters or patches similar to those which have been described for many inputs to the deep SC laminae. A small number of SC-IT cells were also observed in the deep laminae of the tectum contralateral to the thalamic injection. Double labelling experiments using True Blue (TB) and Diamidino Yellow (DY) demonstrated that less than 1% of the contralaterally projecting SC-IT cells also innervated ipsilateral IT. Anterograde tracing with [3H]leucine demonstrated further that SC projected heavily to CL, PC and Pf. This projection also extended into the medial portion of the posterior thalamus (PO).     

Patterns of loss of heterozygosity at 10q23.3 and microsatellite instability in endometriosis, atypical endometriosis, and ovarian carcinoma arising in association with endometriosis.

Genetic aberrations, such as loss of heterozygosity (LOH) and mutations leading to functional inactivation of the PTEN tumor suppressor gene, located on chromosome 10q23.3, have been shown to be associated with approximately one third of ovarian adenocarcinomas. In addition, microsatellite instability (MSI) leading to the functional inactivation of the PTEN gene has also been reported for ovarian adenocarcinomas with frequencies varying from 6 to 37%. However, the frequency of PTEN gene abnormalities has not been well studied or evaluated in lesions such as typical and atypical endometriosis. The aim of this study was to investigate a possible sequential progression from endometriosis through atypical endometriosis to ovarian carcinoma by assessing LOH at 10q23.3 and MSI in those entities. Genomic DNA was analyzed for LOH and MSI at 3 loci on chromosome 10, using polymerase chain reaction amplification. Significant differences in LOH were seen between endometriosis (4.3%) and ovarian carcinoma (23.5%) at D10S608. The differences at the other 2 loci were not significant. A high frequency of MSI was found in endometriosis (82.6%) and atypical endometriosis (75%); however, the differences were not significant. These results suggest that LOH at D105608 may possibly be an important molecular event in the progression of endometriosis to carcinoma. This study highlights that endometriosis and atypical endometriosis might act as precursor lesions that have the potential to progress into ovarian adenocarcinoma.     

The Final Stage of Cholinergic Differentiation Occurs Below Inner Hair Cells During Development of the Rodent Cochlea

To gain further insights into the cholinergic differentiation of presynaptic efferent terminals in the inner ear, we investigated the expression of the high-affinity choline transporter (ChT1) in comparison to other presynaptic and cholinergic markers. In the adult mammalian cochlea, cholinergic axons from medial olivocochlear (OC) neurons form axosomatic synapses with outer hair cells (OHCs), whereas axons from lateral OC neurons form axodendritic synapses on afferent fibers below inner hair cells (IHCs). Mouse brain and cochlea homogenates reveal at least two ChT1 isoforms: a nonglycosylated ∼73 kDa protein and a glycosylated ∼45 kDa protein. In mouse brain, ChT1 is preferentially expressed by neurons in periolivary regions of the superior olive consistent with the location of medial OC neurons. In the adult mouse cochlea, ChT1-positive terminals are located almost exclusively below OHCs consistent with a medial OC innervation. Between postnatal day 2 (P2) and P4, ChT1-positive terminals are below IHCs and occur after the expression of growth-associated protein 43, synapsin, and the vesicular acetylcholine transporter. By P15, ChT1-positive terminals are mostly on OHCs. Accounting for differences in gestational age, the developmental expression of ChT1 in the rat cochlea is similar to the mouse. However, in older rats ChT1-positive terminals are below IHCs and OHCs. In both rat and mouse, our observations indicate that the onset of ChT1 expression occurs after efferent terminals are below IHCs and express other presynaptic and cholinergic markers. In the mouse, but not in the rat, ChT1 may preferentially identify medial OC neurons.     

Intelligent alarms reduce anesthesiologist's response time to critical faults.

The proliferation of monitors and alarms in the operating room may lead to increased confusion and misdiagnosis unless the information provided is better organized. Intelligent alarm systems are being developed to organize these alarms, on the assumption that they will shorten the time anesthesiologists need to detect and correct faults. This study compared the human response time (the time between the sounding of an alarm and the resolution of a fault) when anesthesiologists used a conventional alarm system and when they used an intelligent alarm system. In a simulated operating room environment, we asked 20 anesthesiologists to resolve seven breathing circuit faults as quickly as possible. Human response time was 62% faster, decreasing from 45 to 17 s, when the intelligent alarm system was used. The standard deviations in response time were only half as large for the intelligent alarm system. It appears that the computer-based neural network in the intelligent alarm system diagnosed faults more rapidly and consistently than did the anesthesiologists. This study indicates that breathing circuit faults may be more rapidly corrected when the anesthesiologist is guided by intelligent alarms.     

Laboratory evaluation of the vital signs (ICOR) piezoelectric anesthetic agent analyzer

The Vital Signs (ICOR) anesthetic agent analyzer, which measures anesthetic vapor concentration by a piezoelectric crystal technique, was evaluated by using standard-calibration gases to measure the accuracy, response time, gas interference, and water vapor dependence of the analyzer. The accuracy for the measurement of vapor concentration was better than 0.08 vol%. The reproducibility of repeated measures averaged 0.003 vol%. The offsets caused by other gases were 0.02 vol% for water vapor, 0.08 vol% for 70% nitrous oxide, and less than 0.01 vol% for oxygen and carbon dioxide. Response time (10 to 90%) was 475 ms. The agent analyzer may be well suited for monitoring volatile agent concentrations during anesthesia.     

Supraorbital artery as an alternative site for oscillometric blood pressure measurement

Objective. Noninvasive blood pressure measured from the superficial temporal artery bas been shown to correlate well with pressure in the brachial artery. The supraorbital artery may be an even better site for monitoring blood pressure on the forehead because it originates from the internal carotid artery, and it is easier to locate anatomically. This study compares mean pressure measured oscillometrically over the supraorbital artery and at the upper arm.Methods. Oscillometric signals from the supraorbital artery were recorded in 20 surgical patients under general anesthesia using a 2.5- × 1-cm bladder attached to the forehead with a self-adhesive pad. Blood pressure was measured simultaneously from the arm using a Dinamap 1846 blood pressure monitor, and the resulting data compared with the supraorbital artery measurements.Results. The mean difference between 219 pairs of blood pressure measurements, from the forehead and the arm, was 3.8 mm Hg. The standard deviation of the differences was 7.4 mm Hg. The linear regression equation for the data wasy = 0.98x + 3.25, with a standard error of estimate of 7.31 mm Hg. The correlation coefficient between the two measurements was 0.82.Conclusions. The results show that mean blood pressures measured oscillometrically from the supraorbital and brachial arteries agree and correlate well with each other. The supraorbital artery should be a good alternative site for blood pressure measurement.This article has been used by Tai-Kwong Lee as part of a dissertation, titled Noninvasive blood pressure monitoring from the supraorbital artery of the forehead by oscillometry, submitted to the Department of Bioengineering, University of Utah, in partial fulfillment of the requirements for a doctoral degree, June, 1996.This study was supported, in part, by a grant from Innerspace Medical, Inc., Irvine, CA.     

The superior olivary complex of the hamster has multiple periods of cholinergic neuron development

Cholinergic neurons of the superior olivary complex share a common embryological and phylogenetic origin with brainstem motor neurons and serve as the major descending efferent pathway either to the cochlea as part of the olivocochlear system or to the cochlear nucleus. In this study, we investigated the developmental expression patterns of choline acetyltransferase (ChAT) and its co-localization with calcitonin gene-related peptide within the superior olivary complex and neighboring brainstem motor nuclei. At embryonic day 12, neurons in the ventral nucleus of the trapezoid body were first to express ChAT. The temporal expression pattern of both ChAT mRNA and immunoreactivity in this periolivary region mimicked motor neurons in the facial and trigeminal motor nuclei. Just before birth, shell neurons surrounding the lateral superior olive expressed ChAT. Neither ChAT-positive periolivary neurons nor shell neurons co-expressed calcitonin gene-related peptide during development or in the adult. Immediately following birth, intrinsic neurons within the lateral superior olive expressed ChAT but not calcitonin gene-related peptide. However, a transient increase in the number of ChAT-positive neurons in the lateral superior olive coincided with the onset of the calcitonin gene-related peptide co-expression within these neurons. We conclude that ChAT expression appears first in periolivary regions containing medial olivocochlear neurons, precedes the expression of calcitonin gene-related peptide in the superior olivary complex, and is co-expressed with calcitonin gene-related peptide within the lateral superior olive containing lateral olivocochlear neurons. These data suggest that the lateral olivocochlear system co-expresses ChAT and calcitonin gene-related peptide, whereas the medial olivocochlear system does not.     

How useful are current caries risk assessment tools in informing the oral health care decision-making process?

Background

Caries risk assessment (CRA) tools could address oral health disparities and enhance the efficiency of the oral health care system. The authors aimed to explore the feasibility and limitations of using clinical CRA tools in informing oral health care policy-making processes.

An evaluation of edge effects in nutritional accessibility and availability measures: a simulation study

Background  

This paper addresses the statistical use of accessibility and availability indices and the effect of study boundaries on these measures. The measures are evaluated via an extensive simulation based on cluster models for local outlet density. We define outlet to mean either food retail store (convenience store, supermarket, gas station) or restaurant (limited service or full service restaurants). We designed a simulation whereby a cluster outlet model is assumed in a large study window and an internal subset of that window is constructed. We performed simulations on various criteria including one scenario representing an urban area with 2000 outlets as well as a non-urban area simulated with only 300 outlets. A comparison is made between estimates obtained with the full study area and estimates using only the subset area. This allows the study of the effect of edge censoring on accessibility measures.