Biomedical subjects
P J Stuart
Publications and source records attributed to P J Stuart.
Health implication of occupational exposures to hydrogen sulfide.
A five-year retrospective study of workers exposed to hydrogen sulfide in Alberta, Canada, was conducted, using the records of 250 workers who submitted claims to the provincial compensation board from 1979 through 1983. Fifty-four percent of the exposed workers became unconscious after exposure. Signs and symptoms with a neurological component accounted for the largest group of clinical findings. Respiratory and ophthalmologic effects were the other major groups of signs and symptoms. The overall fatality rate was 2.8%, significantly lower than that reported (6.0%) in a similar study a decade earlier. This is attributed to improved first-aid training and increased awareness of the dangers of hydrogen sulfide. Traumatic injury as a result of a fall after exposure was noted in 31 cases.
Effect of renal denervation on arterial pressure and renal norepinephrine concentration in Wistar-Kyoto and spontaneously hypertensive rats.
Renal norepinephrine (NE) concentration was measured at 2-week intervals after bilateral denervation of the kidneys in 5-week-old Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR). Sham-operated rats of both strains served as controls. Renal denervation significantly delayed but did not prevent the development of hypertension in SHR. Kidney NE concentration in renal-denervated SHR was 13, 25, 33, and 35% of that found in sham-operated SHR at 2, 4, 6, and 8 weeks, respectively, after denervation. Similarly, kidney NE concentration in renal-denervated WKY rats was 11, 24, 32, and 34% of controls but arterial pressure was not significantly altered. Renal-denervated SHR subjected to a second denervation operation 3 weeks after the initial operation continued to develop hypertension similar to those having only one operation. The results of this study support the hypothesis that renal nerves are involved in the hypertensive process in SHR during the early stages and suggest that renal reinnervation may occur within several weeks after denervation; however, the delayed rise in arterial pressure in renal-denervated SHR is not due to renal reinnervation.
Norepinephrine concentration in kidneys of normotensive Wistar-Kyoto and spontaneously hypertensive rats.
Renal norepinephrine (NE) concentration was measured in normotensive Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) at 7, 9, 11, and 13 weeks of age. Although the weight of kidneys was similar in the two strains of rats, renal NE concentration was significantly lower in SHR at all ages (147 +/- 9 to 175 +/- 13 ng/g for SHR, and 216 +/- 8 to 262 +/- 17 ng/g for WKY rats). The difference in renal NE concentration during this time of rapidly increasing arterial pressure in the SHR suggests that renal NE may in some way be related to the development of hypertension.
A case of subdural hematoma and temporal bone fracture as complications of chiropractic manipulation.
We present a case of subdural hematoma and temporal bone fracture as a complication of chiropractic manipulation. Subdural hematoma in the elderly may follow insignificant, often forgotten, trauma and may develop slowly and progress. Our patient presented with a complaint of headache three days after forceful chiropractic manipulation, but denied any history of trauma. Computed tomography confirmed the presence of a subdural hematoma and a temporal bone fracture and the patient underwent successful surgical treatment. Our experience identifies a previously unreported mechanism of injury in patients with subdural hematoma presenting to the emergency department with a complaint of headache.