Accumulation and effects of lead and cadmium on wood ducks near a mining and smelting complex in Idaho

A study of wood ducks (Aix sponsa) was conducted along the Coeur d'Alene River system in northern Idaho in 1986 and 1987. Most of this area has been subjected to severe contamination from lead and other metals from mining and smelting since the 1880s. In 1986, a preliminary study of wood duck nesting was conducted in the contaminated area; incubating hens captured in nest boxes were bled and weighed. Blood samples were used to determine lead and cadmium concentrations and physiological characteristics. In 1987, an intensive study of wood ducks involved trapping and monitoring nest boxes in the contaminated area. Blood and tissue samples were also taken from wood ducks from a reference area without known contamination from metals. Lead levels in blood and tissues of most wood ducks from the contaminated area frequently exceeded those considered hazardous to birds; maximum levels (wet weight) of lead were 8 g g^–1 in blood and 14 g g^–1 in liver. Changes in physiological characteristics constituted the only evidence of potentially adverse effects from lead. In the contaminated area, nesting success (55% unadjusted, 35% Mayfield estimate) was less than in other areas where predation was low and nest boxes were used; but lead concentrations and physiological characteristics of blood were similar in successful and unsuccessful hens.Values of ALAD, hemoglobin, and body mass were negatively correlated with blood concentrations of lead, whereas protoporphyrin was positively correlated with lead levels in the blood. Some of the protoporphyrin values (1,091 g dl^–1 in a male and 756 g dl^–1 in a female) equalled those associated with lead toxicosis in experimental birds. ALAD activity was low in most birds from the contaminated area; values of 0 were obtained from 11 birds. Lead levels in blood, ALAD, protoporphyrin, and hemoglobin were significantly different between birds from the contaminated and reference areas. Concentrations of lead in ingesta of wood ducks ranged from 0.9 to 610 g g^–1 in the contaminated area and 0.2 to 0.6 g g^–1 in the reference area. Levels of cadmium in kidneys of wood ducks ranged from 1g g^–1 to 20 g g^–1 in the contaminated area and from only to 0.1 g g^–1 to 1 g g^–1 in the reference area. Cadmium concentrations were less than known effect levels.     

Use of psychoactive substances in three medical specialties: anaesthesia,medicine and surgery

In order to determine the prevalence of psychoactive substance use in three specialty groupings, 1,624 questionnaires were sent to physicians in medicine, surgery and anaesthesia; all had trained at the same academic institution. A response rate of 57.8% was achieved. Comparison of prevalence of impairment rates showed no differences between Surgery (14.4%), Medicine (19.9%) and Anaesthesia (16.8%). Substance abuse was clearly associated with a family history of abuse; 32.1% of the abusers had a family history of such abuse compared with 11.7% of the non-abusers. Increased stress at various career stages did not appear to increase substance abuse; problem areas during medical life times were similar for each specialty. Substances most frequently used were marijuana (54.7%), amphetamines (32.9%); and benzodiazepines (25.1%). Seventy-three used psychoactive drugs which were non-prescribed. Drug counselling programmes were judged inadequate by most. Use of alcohol and drugs by faculty members was reported by a number of respondents.     

Pharmacodynamics of Phenobarbital Anesthesia and Pentylenetetrazol-Induced Maximal Seizures in a Rat Model of Neoplastic Spinal Cord Compression

The purpose of this investigation was to determine whether paraplegia induced by neoplastic cord compression affects the pharmacodynamics of phenobarbital general anesthesia or of pentylenetet-razol (PTZ)-induced convulsions. Paraplegic rats harboring a thora-columbar epidural tumor, or an identical hindlimb tumor mass, received an i.v. infusion of phenobarbital until the onset of anesthesia. At that point, the phenobarbital concentrations in the CSF and serum were measured. Similarly, PTZ was infused until the onset of maximal seizures. It was found that changes related to systemic tumor growth and newly developed paraplegia due to neoplastic spinal cord compression did not attenuate the pharmacodynamics of phenobarbital. However, sustained paraplegia of 4 days duration reduced CNS sensitivity to the hypnotic action of the barbiturate as evidenced by the higher cerebrospinal fluid phenobarbital concentration required to induce anesthesia (170 ± 31 vs 125 ± 20 mg/L; P < 0.05). On the other hand, sustained paraplegia did not affect brain threshold concentration for PTZ-induced seizures.     

Metastasis of hepatocellular carcinoma to the right colon manifested by gastrointestinal bleeding

An 82-year-old black woman with a history of hepatocellular carcinoma presented with gastrointestinal bleeding. Barium enema and fibrocolonoscopy revealed a 4-cm polypoid mass at the level of the ascending colon with evidence of active bleeding. Biopsies of the lesion proved it to be metastatic hepatocellular carcinoma. Exploratory laparotomy revealed no further dissemination of the tumor, and the patient underwent an ileocolectomy. The serosal side of the colonic lesion was free from tumor, and there was no peritoneal implantation, direct extension, or lymph node involvement. This case represents an extremely rare presentation of metastatic hepatocellular carcinoma.     

Measurement of intracerebral oxygen pressure: practicalities and pitfalls

Two probes, using different technologies, are currently available to measure tissue oxygen pressure. One of these also measures oxygen pressure, carbon dioxide pressure, pH and temperature. Research has delineated normal brain tissue oxygen pressure as 25-45 mmHg and ischemic thresholds of less than 10 mmHg that are related to ischemic injury. Oxygen pressure measures are correlated with other indicators of brain oxygenation such as jugular bulb oxygen saturation and near infrared spectroscopy, but are more reliable for detecting regional ischemic events. Oxygen pressure is correlated with local blood flow in the brain, and treatments that enhance tissue perfusion improve oxygenation.     

Correlates of suffering in amyotrophic lateral sclerosis

OBJECTIVES: 1) To determine the prevalence of pain, suffering, poor quality of life, depression, and hopelessness in people with ALS, and the correlates of suffering and poor quality of life; 2) to analyze the relationship between pain, suffering, quality of life, and attitudes toward life-sustaining medical treatment and physician-assisted suicide; and 3) to determine concordance between patients with ALS and their caregivers in rating the patients' pain, quality of life, and suffering. METHODS: Subjects completed a single interview. We measured the subject's pain, quality of life, suffering, hopelessness, depression, social support, perception of burden to others, level of disability, desire for life-sustaining medical treatment, and interest in assisted suicide. Caregivers also rated the patient's quality of life, pain, and suffering. RESULTS: A total of 100 subjects with ALS and 91 caregivers participated. Suffering was rated as 4 or greater on a six-point scale by 20% of subjects with ALS, and 19% rated their pain as 4 or greater on a six-point scale. Eleven percent had clinical depression. Physicians frequently failed to recognize and treat pain and depression. The correlates of suffering were increasing pain, hopelessness, and level of disability. The correlates of poor quality of life were poor social support and increasing hopelessness. The correlation between subjects' and caregivers' rating of the patient's suffering was r = 0.47. There was no relationship between subjects' ratings of pain, suffering, and quality of life, and their interest in life-sustaining treatment or physician-assisted suicide. CONCLUSION: Many patients with ALS suffer, and their suffering is correlated to pain and hopelessness. Physicians caring for patients with ALS frequently fail to recognize and treat their patients' pain and depression.