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R J Moore

Publications and source records attributed to R J Moore.

143 records · Page 8Linked to original sources
PubMed1975

Partial characterization of the cytosol 3 alpha-hydroxysteroid: NAD(P)+oxidoreductase of rat ventral prostate.

The cytosol 3alpha-hydroxysteroid dehydrogenase of rat ventral prostate has been partially purified. The rates of both the oxidation and reduction by crude and partially purified enzymes have been measured with a variety of radioactive substrates, and the effects of several inhibitor steroids have been assessed. Four conclusions have been drawn from the study. First, no detectable 3beta-androstanediol was formed from dihydrotestosterone, and the oxidation of 3beta-androstanediol was undetectable. Second, the cytosol enzyme exhibits a distinct and unique substrate specificity in that steroids with keto or hydroxyl substitution on the 11th carbon of the steroid cannot serve as substrates or as inhibitors of the enzyme. Third, either 5alpha or 5 beta reduction of delta4,3-keto steroids must take place before the steroids can serve as substrates of the enzyme. Fourth, many delta4,3-keto steroids that cannot act as substrates for the enzyme inhibit the enzyme competitively and may well serve as physiological regulators of the reaction in intact cell.

Animals↗
PubMed1975

Determinants and nature of intramuscular temperature changes during cold therapy.

The purpose of this study was to examine the intramuscular temperature response during an ice massage treatment. In addition, the effect of subcutaneous tissue thickness and limb circumference on temperature changes was investigated. Intramuscular temperature was measured by intramuscular thermocouples each minute during ice massage treatments of five, ten and fifteen minutes. It was shown that ice massage produces a significant drop in intramuscular temperature. However, there was no significant difference in temperature change after five minutes of treatment. In addition it was shown that there is a high multiple correlation between logarithmic time, subcutaneous tissue thickness, limb circumference, and intramuscular temperature change.

Adult↗
PubMedDate not supplied

Influence of the superior colliculus on responses of lateral geniculate neurons in the cat.

The superior colliculus (SC) projects to all layers of the cat's lateral geniculate nucleus (LGN) and thus is in a position to influence information transmission through the LGN. We investigated the function of the tecto-geniculate pathway by studying the responses of cat LGN neurons before, during, and after inactivating the SC with microinjections of lidocaine. The LGN cells were stimulated with drifting sine-wave gratings that varied in spatial frequency and contrast. Among 71 LGN neurons that were studied, 53 showed a statistically significant change in response during SC inactivation. Control experiments with mock injections indicated that some changes could be attributed to slow waxing and waning of responsiveness over time. However, this could not account for all of the effects of SC inactivation that were observed. Forty cells showed changes that were attributed to the removal of tecto-geniculate influences. About equal numbers of cells showed increases (22 cells) and decreases (18 cells) in some aspect of their response to visual stimuli during SC inactivation. The proportion of cells that showed tecto-geniculate influences was somewhat higher in the C layers (68% of the cells) than in the A layers (44% of the cells). In addition, among cells that showed a significant change in maximal response to visual stimulation, the change was larger for cells in the C layers (64% average change) than in the A layers (26% average change) and it was larger for W cells (61% average change) than for X and Y cells (29% average change). Nearly all of the X cells that showed changes had an increase in response, and nearly all of the Y cells had a decrease in response. In addition, across all cell classes, 80% of the cells with receptive fields < 15 deg from the area centralis had an increase in response, and 80% of the cells with receptive fields > or = 15 deg from the area centralis had a decrease in response. None of the LGN cells had significant changes in spatial resolution, and only three cells had changes in optimal spatial frequency. Ten cells had a change in contrast threshold, 25 cells had a change in contrast gain, and 29 cells had a change in the maximal response to a high-contrast stimulus. Thus, our results suggest that the tecto-geniculate pathway has little or no effect on spatial processing by LGN neurons. Rather, the major influence is on maximal response levels and the relationship between response and stimulus contrast.(ABSTRACT TRUNCATED AT 400 WORDS)

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PubMedDate not supplied

Are neurons in cat posteromedial lateral suprasylvian visual cortex orientation sensitive? Tests with bars and gratings.

There is controversy in the literature concerning whether or not neurons in the cat's posteromedial lateral suprasylvian (PMLS) visual cortex are orientation selective. Previous studies that have tested cells with simple bar stimuli have found that few, if any, PMLS cells are orientation selective. Conversely, studies that have used repetitive stimuli such as gratings have found that most or all PMLS cells are orientation selective. It is not known whether this difference in results is due to the stimuli used or the laboratories using them. The present experiments were designed to answer this question by testing individual PMLS neurons for orientation sensitivity with both bar and grating stimuli. Using quantitative response measures, we found that most PMLS neurons respond well enough to stationary flashed stimuli to use such stimuli to test for orientation sensitivity. On the basis of these tests, we found that about 85% of the cells with well-defined receptive fields are orientation sensitive to flashed gratings, and a similar percentage are orientation sensitive to flashed bars. About 80% of the cells were orientation sensitive to both types of stimuli. The preferred orientations typically were similar for the two tests, and they were orthogonal to the preferred direction of movement. The strength of the orientation sensitivity (measured as the ratio of discharge to the preferred and nonpreferred orientations) was similar to both types of stimuli. However, the width of the orientation tuning curves was systematically broader to bars than to gratings. Several hypotheses are considered as to why previous studies using bars failed to find evidence for orientation sensitivity. In addition, a mechanism for the difference in orientation tuning to bars and gratings is suggested.

Animals↗
PubMedDate not supplied

Transneuronal retrograde transport of attenuated pseudorabies viruses within central visual pathways.

Pseudorabies virus (PRV) has been shown to be an effective transneuronal tracer within both the peripheral and the central nervous system. The only investigations of this virus in the visual system have examined anterograde transport of PRV from injection sites in the retina. In the present study, we injected attenuated forms of PRV into the primary visual cortex of both rats and cats to determine whether transneuronal retrograde infection would occur back to the retina. In rats, we made small injections into visual cortex of a strain of PRV (Bartha Blu) that contained a beta-galactosidase promoter insert. In cats, we injected PRV-M201 into area V1 of visual cortex. After a 2- to 4-day incubation period, we examined tissue from these animals for the presence of the beta-galactosidase marker (rats) or the virus itself (cats). Cortical PRV injections resulted in transneuronal retrograde infection of the lateral geniculate nucleus (LGN), thalamic reticular nucleus (TRN), and retina. PRV was retinotopically distributed in the pathway. In addition, double-labeling experiments in cats using an antibody against gamma-aminobutyric acid (GABA) were conducted to reveal PRV-labeled interneurons within the LGN and TRN. All TRN neurons were GABA+, as was a subset of LGN neurons. Only the subset of TRN neurons adjacent to the PRV-labeled sector of LGN was labeled with PRV. In addition, a subset of GABA+ interneurons in LGN was also labeled with PRV. We processed some tissue for electron microscopy to examine the morphology of the virus at various replication stages. No mature virions were detected in terminals from efferent pathways, although forms consistent with retrograde infection were encountered. We conclude that the PRV strains we have used produce a local infection that progresses primarily in the retrograde direction in the central visual pathways. The infection is transneuronal and viral replication maintains the intensity of the label throughout the chain of connected neurons, providing a means of examining detailed circuitry within the visual pathway.

Animals↗
PubMedDate not supplied

The fate of the coracoacromial ligament in arthroscopic acromioplasty: an anatomical study.

This study defines the normal anatomical relationships among the coracoacromial ligament, the deltoid, and the acromion in cadavers. The effect of arthroscopic acromioplasty on the acromial attachments of the coracoacromial ligament and the anterior fibers of the deltoid was also studied. After arthroscopic acromioplasty, the fibers of coracoacromial ligament and overlying deltoid inserting into the anterior part of the acromion remained attached to the acromion by a bridge of tissue composed of periosteum and collagen fibers of the coracoacromial ligament and deltoid tendon. We have called this the coracoacromial-deltoid-periosteal complex; it has not previously been described. This study demonstrates that arthroscopic acromioplasty preserves the acromial attachment of the coracoacromial ligament and the anterior fibers of the deltoid.

Acromion↗
PubMedDate not supplied

Racial disparity in survival of patients with squamous cell carcinoma of the oral cavity and pharynx.

BACKGROUND: This study was designed to determine if race and age are independent prognostic factors for survival in patients treated for squamous cell carcinoma of the oral cavity and pharynx. METHODS: Retrospective study. RESULTS: Out of 909 patients registered, 815 (90%) were white and 94 (10%) were African-American. The median age was 60 years (range 19-93). The African-American patients had a significantly lower 5 year survival rate of 27.6% (95% CI 19.9-38.3) compared with white patients with a survival rate of 52.0% (95% CI 48.7-55.6) (P < 0.001). The greatest racial disparities in survival were observed in patients under 60 years of age [29.2% (95% CI 19.5-43.6) vs 60.9% (95% CI 56.3-66.0) for African-American and white patients, respectively, P < 0.001], and in African-American men compared with white men [20.2% (95% CI 12.6-30.2) vs 51.0% (95% CI 46.7-53.0), P < 0.001]. A multivariate Cox model, stratified according to stage of disease, indicated that race, age, and type of treatment were statistically significant predictors of survival. After adjusting for race and treatment received, African-American patients had a relative risk of dying of 1.61 (95% CI 1.23-2.10) compared with white patients. All patients 60 years of age and older had a higher risk of dying 1.59 (95% CI 1.31-1.92). Compared with surgical treatment alone, radiotherapy and other treatments were both associated with increased risk of dying with respective relative risks of 1.34 (95% CI 1.01-1.76) and 1.94 (95% CI 1.52-1.48). CONCLUSIONS: African-American patients had poorer survival outcomes, with race and age emerging as significant independent predictors of survival after treatment for oral and pharyngeal cancer, compared with their white counterparts. Primary and secondary prevention programs that target younger patients at high risk might reduce environmental risk factors such as smoking and alcohol consumption, which may play a greater role in the acquired susceptibility for oral and pharyngeal cancer in African-American males.

Adult↗
PubMedDate not supplied

A voice that wraps around the body--communication problems in the advanced stages of non-small cell lung cancer.

INTRODUCTION: Significant problems in clinician-patient communication have been described in the oncology literatures. Advanced stage non-small lung cancer a devastating disease, can cause the communication between survivors, significant others, and clinicians to falter. To date, however, no studies have used qualitative methods to examine experiential aspects of living with non-small cell lung cancer. Nor have any studies evaluated the tools survivors might use to repair some of the damage caused by living with this disease. METHODS: Exploratory, two-part qualitative design. RESULTS: Survivors of non-small cell lung cancer live with multiple fears and losses. These include a diminished sense of self, the loss of health, fears of pain in a future tainted by the threat of death, and increased feelings of alienation due to the loss of previous sources of meaning in life. These experiences significantly affect cancer survivors abilities to communicate with clinicians and significant others. CONCLUSIONS: Survivors of non-small cell lung cancer often have difficulty sharing their experiences with others not suffering a similar affliction. Through their narratives with other survivors, however, patients are better able to initiate a biopsychosocial mechanism which enables them to create a cognitive map. This cognitive map helps survivors share their experiences with others, thereby repairing some of the damage caused by this disease, including the harm done to their communication with other people.

Adult↗
PubMedDate not supplied

CT scanning phantom for normalization of infant brain attenuation.

The x-ray attenuation values of brain studied with computed tomography (CT) are strikingly affected by the ages of the subjects. Premature neonates, for example, may have brain attenuation values 20-30 H below adult values. These lower attenuation values for developing compared with adult brain can be ascribed partly to machine-related effects (beam-hardening, adult algorithms, scanning geometry, etc.). A scanning phantom made from aluminum was developed that can be used to develop a nomogram for any particular scanner from which normalized brain attenuation may be derived for any small head size. Using this nomogram, predicted neonatal attenuations are still 10-15 H higher than those actually observed in scanning neonates. The model predicts that, at the most, 3-4 H of this discrepancy can be accounted for by less beam-hardening from the lower bone attenuation of the thinner developing skull. Presumably, the rest is from a lower brain density in neonates (higher water content). By normalizing to cerebrospinal fluid (water) with special care to avoid partial-volume artifacts, one can predict attenuation values for developing brain more accurately.

Aluminum↗