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T Sutton

Publications and source records attributed to T Sutton.

9 recordsLinked to original sources

Doppler detection of decompression bubbles with computer assisted digitization of ultrasonic signals.

Precordial Doppler ultrasonic monitoring is routinely used for detection of venous gas bubbles resulting from decompression in hypobaric or hyperbaric applications. Bubble scoring codes have been devised in an attempt to quantify the number of audible bubble signals heard over the background sounds of the cardiac cycle. The audio interpretation of these ultrasonic backscatter signals remains the most common method for decompression evaluation. We report on the use of an inexpensive, commercially available audio digitizer in conjunction with a personal computer to digitize Doppler bubble signals for visual and electronic evaluation. This device can be operated simultaneously with Doppler audio monitoring. Precordial and arterial Doppler recordings of gas bubbles were obtained from anesthetized dogs after intravascular infusion or following decompression. Additional evaluations were conducted on Doppler bubble recordings obtained from human decompression studies. The device can be used in real-time or for later signal analysis. Accompanying menu-driven software provides for numerous signal modification options and visual displays. This device can provide a simultaneous visual display of Doppler signals normally only available for audio evaluation.

Animals

Comparative toxicology of temelastine. A novel H1 antagonist in dog, rat, and monkey.

The toxicity of temelastine 2-[4-(5-bromo-3-methylpyrid-2-yl)butylamino]-5-[(6-methylpyrid+ ++-3-yl) methyl]-4-pyrimidone a potent, selective, competitive histamine H1-receptor antagonist was examined in dogs and rats. The major toxicological response seen in the dog was marked, but intermittent and reversible, increases in the plasma activity of a number of liver-associated enzymes, viz alanine aminotransferase (ALT), glutamate dehydrogenase (GLDH), and alkaline phosphatase (ALP). The increases first seen in two male dogs treated for 30 consecutive days at a dose of 300 mg/kg became apparent at lower doses, i.e., 100 and 33.3 mg/kg/day, in 6- and 12-month studies. Although the increases were suggestive of hepatotoxicity, the only histological changes were increases in hepatocellular lipofuscin pigment and foci of macrophages seen in dogs treated at 300 mg/kg for 12 months. Rats treated for up to 12 months at doses as high as 300 mg/kg/day showed no treatment-related increases in plasma enzymes although increases in liver weights and hepatocellular lipofuscin pigment together with centrilobular hypertrophy were seen in the 300 mg/kg/day treatment group. To investigate differences in hepatic responsiveness between species dogs, rats, and monkeys were exposed to high concentrations of temelastine by continuous 24-hr intravenous infusion. The results of the study showed the dog to be most sensitive to the hepatic effects of temelastine. The major toxicological effect of temelastine in the rat was a histopathological lesion of the thyroid gland characterized by agglomeration and depletion of colloid, follicular epithelial hypertrophy and reduced follicular size. The no-effect dose for this lesion was between 10 and 33.3 mg/kg/day. These histopathological changes, characteristic of a "TSH-driven" thyroid gland, were not seen in the thyroid glands of dogs.

Alanine Transaminase

Effect of the Trendelenburg position on the distribution of arterial air emboli in dogs.

We examined the effects of buoyancy on the distribution of arterial gas bubbles using in vitro and in vivo techniques in dogs. A simulated carotid artery preparation was used to determine the effects of bubble size and vessel angle on the velocity and direction of bubble movement in flowing blood. Because buoyancy tends to float bubbles away from dependent areas, bubble velocity would be expected to decrease as the vessel angle increased. We found that larger bubbles increased in velocity in the same direction as the blood flow at 0-, 10-, and 30-degree vessel angles and decreased when the vessel was positioned at 90 degrees. Smaller bubbles did not change velocity from 0 to 30 degrees and increased in velocity in the same direction as blood flow at 90 degrees. In 10 anesthetized dogs, we studied the effects of 0-, 10-, 15-, and 30-degree Trendelenburg's position on carotid artery distribution of gas bubbles injected into the left ventricle or ascending aorta. Regardless of the degree of the Trendelenburg position, the bubbles passed into the carotid artery simultaneously with passage into the abdominal aorta. We conclude that the forces of buoyancy do not overcome the force of arterial blood flow and that the Trendelenburg position does not prevent arterial bubbles from reaching the brain.

Animals

Villous and tubulovillous adenomas of the colon and rectum. A retrospective review, 1964-1985.

The records of 1,040 patients with 1,440 villous and tubulovillous adenomas of the colon and rectum treated at the Cleveland Clinic over a 21 year period were reviewed. The incidence of invasive adenocarcinoma was higher in patients with multiple adenomas at the time of presentation, in patients with a family history of colorectal cancer, and in those with adenomas greater than 4 cm in diameter. Eighty percent of the adenocarcinomas were Dukes' A or B, 15 percent were Dukes' C, and 5 percent presented with distant metastases. Clinical impression on examination was more accurate than biopsy in assessing the presence of malignancy in these tumors. Recurrence after local treatment of both benign and malignant tumors was high. Recurrence was significantly related to the size of the adenoma (more common when the tumor was more than 4 cm in diameter), location (more common when it was located in the rectum), and the type of treatment. Only 4 percent of the patients had died from colorectal cancer at the time of follow-up. The overall 5 year actuarial survival rate was 85 percent.

Adenocarcinoma

The syndrome of accelerated bone maturation in the newborn infant with dysmorphism and congenital malformations. (The so-called Marshall-Smith syndrome).

A new case of the syndrome of "accelerated skeletal maturation, facial dysmorphism, failure to thrive and psychomotor retardation" is presented. The syndrome was noted in the neonatal period. The diagnosis can be readily suggested by the radiologist because ossification centers show exceptionally early maturation. This case history increases to at least five the number of cases so far reported following the initial publication by Marchall and al. in 1971. If the two cases described in 1974 by Weaver and al. (as a distinct entity) are also included then the total of cases reported rises to seven.

Abnormalities, Multiple

Material benefits.

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Catheters, Indwelling