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E Walters

Publications and source records attributed to E Walters.

11 recordsLinked to original sources

Receptor neuron losses result in decreased cytochrome P-450 immunoreactivity in associated non-neuronal cells of mouse olfactory mucosa.

Immunohistochemical and immunoblot analyses were used to investigate nasal cytochrome P-450 distribution in mice with either unilateral naris closure for 3, 4, or 5 months, or olfactory bulbectomy. P-450 immunoreactivity was observed only in the supporting cells and Bowman's glands of the olfactory mucosa. Immunoreactivity was clearly reduced in rostral regions of the open-side olfactory mucosa where losses of receptor neurons resulted from 3 to 5 months of closure. Closed-side immunoreactivity was similar to controls. In 4 month closure animals that had regrown their receptor neurons, open-side immunoreactivity was comparable to controls. Olfactory bulbectomy also depressed P-450 immunoreactivity. These data suggest that presence or absence of receptor neurons markedly affects P-450 expression in nonneuronal cells of the olfactory mucosa.

Animals

The sensitivity of Drosophila larvae to continuous-wave ultrasound.

The threshold for killing of freshly hatched Drosophila larvae exposed to continuous-wave (CW) ultrasound shows a minimum at approximately 0.3 MHz. This suggests that the stiffness of the material surrounding the gas bodies in the organism is comparable to water. From this, it is apparent that the gas bodies in three-day-old larvae that we have used in earlier studies are far larger than resonance size at the frequencies (1-5 MHz) used. Yet, these larvae were killed by short exposures to low-temporal-average-intensity pulsed ultrasound with peak intensities of the order of 10 W/cm2. Hence, it appears that "large" bubbles cannot be ignored in considerations of the biological effects of pulsed ultrasound and lithotripsy.

Animals

Pleural effusion: an "acoustic window" for sonography of pleural metastases.

We report the sonographic findings in 32 patients with malignant disease associated with pleural effusions diagnosed by chest roentgenograms. No tumor lesions were seen in any case on X-ray films. Thoracic sonography, however, detected previously undocumented metastatic disease with diaphragmatic (N = 19), parietal (N = 8), visceral (N = 2) or combined (N = 3) pleural involvement. Additionally, a distinction could be made between nodular lesions (N = 19), sheet-like tumor masses (N = 10), and combined (N = 3) tumor spread. In all cases thoracentesis was performed. Cytology showed malignant cells in 28 patients. Pleural metastasis was histologically confirmed by ultrasound-guided fine needle biopsy in 2 cases. The present study demonstrates the value of scrutinized thoracic sonography in patients with pleural effusion for the detection of pleural metastases.

Adult

Pharmacokinetics of cefamandole and ampicillin in experimental meningitis.

The penetration of cefamandole and ampicillin into the cerebrospinal fluid of rabbits with and without pneumococcal meningitis was evaluated. In normal animals, a mean maximum concentration of 0.22 +/- 0.13 microgram of cefamandole per ml was measured in the spinal fluid after a dose of 150 mg/kg given intramuscularly; with 25 and 50 mg/kg doses, no antibiotic was detected in the cerebrospinal fluid. With ampicillin, in intramuscular doses of 200 and 300 mg/kg, the mean maximum concentrations encountered in the cerebrospinal fluid were 1.59 +/- 0.4 and 1.47 +/- 0.44 microgram/ml, respectively. Penetration of cefamandole, and to a lesser extent ampicillin, was increased after 24 h of experimental meningitis. With cefamandole, the concentration of drug in the cerebrospinal fluid exceeded the usual inhibitory concentration for Haemophilus influenzae only with the 150 mg/kg dose. After 48 h of meningitis, there was a trend toward higher levels of antibiotic in the cerebrospinal fluid, but the difference between animals infected 24 versus 48 h was not statistically significant. In animals with meningitis, serum concentrations after 150 mg of cefamandole per kg and both ampicillin doses studied were 32 to 38% lower than the serum levels achieved in normal rabbits after identical doses of antibiotic.

Ampicillin

Impaired granulocyte adherence. A reversible defect in host defense in patients with poorly controlled diabetes.

When the ability of granulocytes from 10 poorly controlled diabetic patients with fasting hyperglycemia and no evidence of ketoacidosis (mean fasting glucose 293 +/- 20 mg. per 100 ml.; mean +/- S.E.M.) to adhere to a nylon fiber column was assessed, the number of adherent granulocytes from whole blood was only 53 +/- 6 per cent of the values observed in controls. After antidiabetic treatment for one to two weeks and lowering of fasting glucose levels (mean 198 +/- 29 mg. per 100 ml.), adherence improved significantly (p less than 0.01) in the diabetics; however, their values were still subnormal (diabetic 74 per cent +/- 8 of control; p less than 0.02). Adherence values before and after treatment correlated with the fasting glucose level (r = 0.88, p less than 0.001). These findings suggest that, in addition to previously reported abnormalities in migration and the ingestion and killing of bacteria, granulocyte adherence may also be impaired in poorly controlled diabetic patients. This functional abnormality correlates directly with the fasting glucose and is reversed by insulin treatment. A defect of this type may compromise the normal inflammatory response in some diabetics and impair their capacity to resist infection.

Blood Glucose

Experimental pneumococcal meningitis. IV. The effect of methyl prednisolone on meningeal inflammation.

This study was undertaken to determine whether adrenal corticosteroids suppress meningeal inflammation in experimental pneumococcal meningitis in rabbits and, if so, whether the mechanism of suppression involves inhibition of chemotactic activity in CSF or modification of granulocyte responses to inflammation mediators. It was found that methyl prednisolone, administered intramuscularly in doses of 15 or 30 mg/kg 24 hr and 48 hr after induction of meningitis, significantly reduced (p less than 0.01) the mass of granulocytes present in the meninges 72 hr after infection, the time of maximum meningeal inflammation. The larger dose of steroid produced approximately twice the suppressive effect of the smaller dose (p less than 0.05). The regime of methyl prednisolone that produced maximal suppression of meningeal inflammation (30 mg/kg/day) did not alter CSF chemotactic activity or chemotactic responsiveness and phagocytic activities of granulocytes from rabbits with meningitis. However, steroid therapy inhibited an increase in granulocyte adherence that was observed in untreated animals with meningitis (p less than 0.05). Thus methyl prednisolone in doses of 15 and 30 mg/kg given daily to rabbits with pneumococcal meningitis produced a suppressive effect on meningeal inflammation that was dose-dependent and was possibly mediated by inhibition of granulocyte adherence.

Animals

Orbital dystopia: attempts to evaluate the results of surgery.

This study has shown that surgery for hypertelorism or vertical orbital dystopia gives very satisfying results overall to the patients and their families and leads to a modest but highly significant objective improvement in appearance after surgery, as perceived by panels of laymen or hospital staff not known to the patients. The complexities of the methodology of panel assessments of appearance are discussed. The results of this study confirm the need to go beyond our traditional methods of assessing surgical outcome simply within our specialty.

Adolescent