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Biomedical subjects

J S Bell

Publications and source records attributed to J S Bell.

At least 37 records · Page 2Linked to original sources

Hepatocyte changes following selenium accumulation in a freshwater teleost.

This report provides morphological and analytical data for a group of green sunfish collected from an area relatively free of metals and a second group of the same species collected from a lake into which selenium had been discharged. Neutron activation data of livers (and kidneys) collected from these fish show an average of about 11 ppm selenium (fresh weight) for both organs; other metals were not detected in the liver (or kidneys) of these fish. Ultrastructural examination of livers from fish of this group showed focal necrosis, areas of granular cytoplasm, fatty infiltration, increased numbers of Kupffer cells, and disorganized liver architecture--compared with those of controls. The presence of massive levels of selenium in the liver and concomitant hepatocyte changes suggests a causal relationship between these phenomena.

Animals↗

Histopathological changes in selenium-exposed fish.

Redear sunfish (Lepomis microlophus) were collected from Martin Lake in east Texas. For at least 8 months, 1 year earlier, aqueous selenium-laden effluent from man-made sources was released into this 5,000-acre reservoir (unpublished data). Redear sunfish from a reference lake, 8 km upstream, were collected for comparison to Martin Lake fish. The hepatopancreas (i.e., liver and associated, disseminated exocrine pancrease), mesonephros (i.e., kidney), gonads, heart, spleen, stomach, and gill arches were preserved for histopathological examination using optical and/or transmission electron microscopy. Livers from Martin Lake redear sunfish (which had accumulated approximately 20 ppm selenium in the liver) showed central necrosis, reduced quantities of rough endoplasmic reticulum and glycogen particles, and increased numbers of lysosome-like structures. Kidneys showed proliferative glomerulonephritis, and exocrine pancreas showed marked hypertrophy at the optical level. Ultrastructurally, architectural disorganization, reduced rough endoplasmic reticulum, increased cisternal space, and proliferation of smooth endoplasmic reticulum were evident. The stomach, spleen, gill, heart, and gonads showed no abnormalities.

Animals↗

Renal changes in selenium-exposed fish.

A group of green sunfish was collected from a selenium-rich lake and compared with a similar group collected from a control lake upstream in the same drainage system in east Texas. Since the level of selenium in kidneys of these fish was relatively high (averaging 11 ppm on a fresh weight basis), histopathological and ultrastructural data were collected. Kidneys from fish from the selenium-rich lake showed proliferative glomerulonephritis and hematuria as well as vacuolation and necrosis of cells of the convoluted tubules.

Animals↗

Sudden death due to spontaneous rupture of the spleen from infectious mononucleosis.

An 18-year-old white male showing no external signs of trauma was discovered dead in his bathroom. A ten-day history of illness resulting in symptomatic treatment for viremia one day before death was elicited. Autopsy revealed splenic rupture, massive peritoneal hemorrhage, and atypical lymphocytes. Laboratory tests on postmortem samples confirmed the diagnosis of infectious mononucleosis.

Adolescent↗

Disopyramide (Norpace) distribution at autopsy of an overdose case.

A 44-year-old female died as the result of an overdose of disopyramide. An analytical method was developed and the distribution of the drug in various tissues was determined. Analysis of the blood sample indicated a drug concentration far exceeding that of the therapeutic concentration.

Adult↗

The use of EEG theta biofeedback in the treatment of a patient with sleep-onset insomnia.

In this report, the treatment of a 42-year-old female with a complaint of chronic sleep-onset insomnia is described. Following the unsuccessful use of relaxation training, treatment consisted of 11 sessions of EEG theta rhythm (4--7 Hz) biofeedback. Theta density and five sleep indices were monitored throughout baseline, placebo, and treatment sessions. A significant increase in theta density was accompanied by reports of a decrease in sleep latency and an increase in total sleep time. This improvement was maintained after withdrawal of medication and at 3-month follow-up.

Adult↗

Sleep apnea and Q-T interval prolongation--a particularly lethal combination.

We have discovered a 20-day-old infant who possessed anatomic evidence of chronic hypoxemia with right ventricular hypertrophy and who died in hypoxic hypoxemia with a postmortem PO2 of 4 mm. Hg. Subsequently, and ECG was discovered which had been obtained at one day of age and showed Q-T interval prolongation along with T-wave alternation. We believe this case to be one of the first to substantiate the mechanism for SIDS as proposed by Schwartz, 26 with hypoxia acting synergistically with a prolonged Q-T interval causing sudden unexpected death in this infant--providing a link between cardiac and respiratory mechanisms of death.

Adult↗

Prolongation of the Q-T interval in a victim of sudden infant death syndrome: cause or effect?

A 3-week-old infant died of sudden infant death syndrome (crib death, cot death). Although prolongation of the Q-T interval was found on an electrocardiogram taken at birth, this child appeared to have died of terminal respiratory failure as judged by a postmortem arterial oxygen tension of 4 mm Hg. The heart showed right ventricular hypertrophy, a finding consistent with chronic hypoxemia. The prolongation of the Q-T interval may have contributed to the death of this child with hypoxia predisposing to a fatal episode of ventricular fibrillation.

Cardiomegaly↗