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Over the period 1977-2000, eggs of Pacific great blue heron (Ardea herodias fannini) were collected from 23 colonies along the southern coast of British Columbia, Canada, and analyzed for persistent organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs). Concentrations of OC pesticides in eggs declined sharply in the late 1970s, after which there were minimal changes. The sums of PCB congeners were not reduced appreciably during the 1980s and 1990s, but Aroclor 1260 concentrations suggested a sharp decline in PCB contamination of eggs in the late 1970s, similar to that shown for OC pesticides. Eggs collected along or near the Fraser River delta showed higher levels of most pesticides compared to other monitored colonies. Although the delta lands support a long-standing agricultural economy, the primary factors influencing OC levels in the delta colonies were thought to be driven by estuarine processes. We suggest two possible influencing factors were: 1) a greater rate of bioaccumulation in the estuary due to the deposition of particulates collected over a vast area encompassed by the Fraser River watershed; or 2) a higher rate of biomagnification in the estuary due to species differences at lower trophic levels of the heron food chain. Eggs from urban colonies contained higher levels of PCBs. The congener pattern was not clearly different from that observed in less contaminated eggs from rural and pulp mill-influenced colonies, except that colonies in Vancouver had greater proportions of PCB-66, suggesting a local source of Aroclor 1242. Productivity in the coastal heron colonies was highly variable over the period of study, with 71% of recorded colony-wide reproductive failures occurring in colonies near pulp mills. However, the predominant factors influencing reproductive success were probably disturbance by humans and bald eagles, combined with loss and degradation of nesting habitat, and not sublethal toxicity.

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Information processing deficits were explored in a large cohort of schizophrenia patients (N = 125) and non-psychiatric subjects (N = 52). Gender, medication status and symptom factors were assessed relative to measures of performance in critical stimulus duration (CSD), visual backward masking (VBM) and auditory reaction time (RT) paradigms. Schizophrenia patients exhibited significant impairments in measures of CSD, VBM and both RT speed and RT set. Females in both groups had inflated CSDs relative to males. Female schizophrenia patients showed slower RTs and elevated RT set scores, but comparable VBM performance, when compared to males. This gender difference was not observed in the non-psychiatric subjects. To test the hypothesis that impaired performance in the VBM and RT paradigms would be related to negative symptoms and thought disorder, regression analyses were performed using factor scores derived from a factor analysis of SANS and SAPS items that generated three symptom factors: negative, disorganized, and reality distortion. Significant variance in performance on VBM and RT measures was accounted for only by the negative symptom factor. We conclude that VBM and RT assess information processing deficits in schizophrenia patients that are more related to the negative versus positive or disorganized symptoms of schizophrenia. It is possible that VBM and RT share overlapping or interacting neural substrates.

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Investigated the incidence and severity of Posttraumatic Stress Disorder (PTSD) in childhood cancer using informant methodology. The parents of pediatric cancer patients (n = 30) and off-treatment survivors (n = 42) completed a modified version of the Posttraumatic Stress Disorder Symptom Scale (PSS) on their children (M age = 8.8: SD = 4.0), in addition to the Child Behavior Checklist (CBCL) and the Personality Inventory for Children (PIC). Medical treatment and demographic data were also collected for each child. The only variables that significantly identified the presence of symptoms of PTSD were being on treatment at the time of the evaluation or in the preparatory phase prior to bone marrow transplantation and not having received cranial irradiation. Results indicate that a full constellation of PTSD symptoms can occur in children over the course of cancer treatment. Within the off-treatment pediatric cancer survivors, however, the incidence of PTSD was no greater than epidemiological estimates from the general population. The concurrent validity of the PSS received support, and the results, while preliminary, suggest that extended periods of medical trauma during which emotional support is present may not excessively predispose children to PTSD.

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The possible presence of hallucinations and delusional thoughts in posttraumatic stress disorder (PTSD) was investigated. Other symptom clusters were also assessed in order to further clarify the nature of PTSD. Twenty combat veterans with PTSD were compared to 18 combat veterans without PTSD on symptom rating scales. The subjects with PTSD exhibited a greater degree of depression, anxiety, agitation, anhedonia, and positive symptoms of psychosis than the comparison group. Specifically, the PTSD group manifested increased hallucinations, delusions, and bizarre behavior. Some of these positive symptoms did not appear to be due to reexperiencing of the trauma. The groups were not significantly different on indices of mania, thought disorder, or inertia. The clinical and diagnostic implications of the results are discussed. A diagnosis of PTSD should be considered with patients who have positive symptoms in the absence of thought disorder.

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This study investigated the relation of cognitive coping and catastrophizing to acute postoperative pain and analgesic use. Fifty-nine women who had just undergone breast cancer surgery rated their pain on 3 consecutive days and completed a self-report measure of cognitive coping and catastrophizing prior to hospital discharge. Analgesic use over the 3-day period was tabulated from pharmacy records. Based on prior research, it was hypothesized that increased catastrophizing and decreased use of cognitive coping strategies would be associated with greater pain and analgesic use. Results partially confirmed these hypotheses. Catastrophizing, but not cognitive coping, was associated with individual differences in pain intensity and analgesic use. Additional analyses indicated that age was a significant predictor of both catastrophizing and postoperative pain. Specifically, younger patients were more likely to catastrophize and to report increased postoperative pain. Theoretical and clinical implications of these findings are discussed.

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PURPOSE: To investigate the neuropsychologic effects of cranial irradiation (CRT), intrathecal methotrexate (IT-MTX), and systemic methotrexate (SYS-MTX) in a cohort of pediatric patients with cancer who had either received no, moderate, or high doses of these treatments alone or in various combinations. PATIENT AND METHODS: Data were collected on 120 pediatric cancer patients from a large variety of diagnostic groups. Patients completed a comprehensive neuropsychologic test battery designed to assess most areas of cognitive functioning. In analyzing cancer treatment effects, the following variables were statistically controlled: (1) age, (2) socioeconomic status (SES), (3) age at diagnosis, (4) months since both onset and cessation of CNS treatments, (5) time missed from schooling, and (6) presence/type of CNS cancer. RESULTS: CRT, largely in combination with IT-MTX, was significantly associated with deficits in several, primarily nondominant, hemispheric neuropsychologic functions, even after control and other treatment variables were addressed. This relationship was somewhat, but not highly, dose-dependent at CRT doses greater than approximately 18 Gy, at least over the first several years posttreatment. While there was statistically significant evidence for cognitive impairment, absence from school during treatment and age at diagnosis were more predictive of reading and spelling academic achievement than having received CRT. IT-MTX and SYS-MTX alone were not associated with significant degrees of neuropsychologic involvement. CONCLUSION: CRT, especially when administered with IT-MTX, at currently used dosages was associated with significant neuropsychologic impairment in children. These impairments are most likely to be reflected in nonverbal intelligence, perceptual abilities, and susceptibility to distraction. IT-MTX and SYS-MTX did not result in a consistent pattern of cognitive deficit.

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OBJECTIVE: Careful assessment of research subjects is important because the inclusion of subjects who manifest psychopathology and significant substance abuse in normal comparison groups will decrease statistical and experimental power. The current study evaluated the usefulness of an MMPI-derived algorithm in identifying tendencies toward psychosis and substance abuse in putatively normal research volunteers. METHOD: Ninety-eight adults who were recruited as normal comparison research subjects completed the MMPI, psychiatric interviews, questionnaires, and selected neuropsychological tests. The MMPI classified 81 presumed normal subjects into four subgroups: 1) not psychosis prone/substance abuse not likely, 2) not psychosis prone/substance abuse likely, 3) psychosis prone/substance abuse not likely, and 4) psychosis prone/substance abuse likely. RESULTS: The MMPI psychosis-prone and substance abuse factors identified significantly distressed and dysfunctional individuals with a relatively high degree of accuracy. CONCLUSIONS: It is becoming increasingly apparent that the cursory self-report screening of normal subjects may result in unacceptable levels of psychopathology in comparison groups. The current results also indicate that an adequate substance abuse evaluation is extremely important and that brief self-report information may be misleading. Empirically derived assessment tools, such as the MMPI, may prove useful in allowing researchers to more accurately define control parameters and group membership.

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Reviewed 53 studies on the effects of central nervous system prophylactic treatment (CNSPT) on cognition and neuropsychological functioning. CNSPT involves irradiation and/or chemotherapy directed to the brain, and is frequently administered to children who have leukemia. The effects of CNSPT on neuropsychological functioning in long-term cancer survivors remains controversial. A number of studies failed to identify any neuropsychological impact secondary to CNSPT, whereas others reported deficits that appear to be a function of CNSPT. Several methodological issues that make it difficult to draw meaningful conclusions from this research literature are identified and discussed. Specific recommendations are made for improvements in research on CNSPT in children.

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Some, although not all, researchers have reported dramatically increased numbers of perseverative responses on the Wisconsin Card Sorting Test (WCST) in schizophrenic patients compared to normal comparison subjects. The current study was designed to further explore the nature of possible WCST deficits in a group of paranoid schizophrenic patients compared to normal and psychiatric comparison subjects. In the current study, schizophrenic patients had significantly greater numbers of perserverative responses on the WCST than the comparison groups. The sample of patients with schizophrenia appeared to be characterized by a non-Gaussian distribution of perseverative responses on the WCST. WCST-impaired and WCST-nonimpaired schizophrenic subgroups were compared on cognitive and symptom measures, and increased perseverative responding was associated with negative symptoms, slowed reaction time, and more hospitalizations. While additional research is necessary to further investigate hypotheses of frontal versus generalized brain dysfunction in schizophrenic patients, WCST impairment seems to be present in a clinically meaningful subgroup of paranoid schizophrenic patients.

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Delusions are often prominent symptoms in schizophrenia and other psychiatric and neurologic disorders. Despite the central descriptive importance of delusions, there is a paucity of comprehensive reviews, theoretical formulations, and empirical evaluations in this area. Research and theoretical work pertinent to delusions are reviewed with particular emphasis on current findings in the neurobiological, cognitive, and information-processing literature. Research on delusional thought seen in various psychiatric disorders is reviewed and integrated with critical aspects of schizophrenia research. Consideration of three factors may help in understanding delusional thought processes. These factors are state-trait variables, perseverative thought, and cognitive functional integrity.

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One of the diagnostic criteria for posttraumatic stress disorder (PTSD) is an exaggerated startle response; however, this phenomenon has not been verified empirically. The authors compared 20 Vietnam combat veterans with PTSD and 18 combat veterans without PTSD on the eyeblink reflex electromyographic response of the startle reaction. Subjects in both groups who failed to show an eyeblink response to the startle stimuli were eliminated from further analyses. Among the remaining subjects, the 13 with PTSD had a significantly greater startle response amplitude than the 12 control subjects at intermediate intensities of acoustic stimuli. The relationship between startle responsivity and both negative and positive symptoms was also investigated.

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The possibility that Damalinia ovis ingests intact epidermis could explain economically important irritation behaviour by infested sheep. To test this, feeding lice were observed on sheep by hand lens and macrophotography and on light and scanning electron microscope preparations. Aspects of feeding behaviour were described, particularly an epidermal ingestion posture. Louse ingesta were examined in paraffin and frozen sections. Lipid-covered stratum corneum squames were identified in crop, midgut, rectum and faeces. Nucleated keratinocytes from inner epidermal strata were not seen, neither were wool fibres. Vertical frozen sheep skin sections, with feeding lice cryofixed by liquid nitrogen, showed mandibles engaged in the outer stratum corneum of the epidermis. The epidermal origin of some ingesta was confirmed by confirming lice over sheep whose skin was stained with Oil Red O, whose colour was seen in crop, midgut, rectum and faeces of harvested lice. Lipase was found in louse midgut. It was concluded that sebaceous secretions may form an important component of the D. ovis diet. The relative contribution from loose scurf or from stratum corneum squames was not determined. Mechanical stimuli by feeding lice did not seem to be the source of host irritation. The role of sensitising agents in louse brei filtrates was investigated with inconclusive results. Intradermal injections of louse faeces did not elicit a demonstrable response.

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In 1986, eggs were collected and productivity estimated at four great blue heron (Ardea herodias) colonies on the coast of British Columbia. Polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were present in all eggs in a qualitatively similar pattern among colonies. PCDD levels were significantly elevated at a colony near a kraft pulp mill at Crofton on Vancouver Island, although there was no correlation between the number of young raised in a nest and levels of either PCDDs, PCDFs, PCBs, organochlorine pesticides or mercury. In 1987, heron productivity was normal at three colonies, while the colony at Crofton failed to raise any young. A normal complement of eggs were apparently laid in about 57 nests, but during incubation they were destroyed and the broken eggshells were found in and beneath the nests. Analysis of eggs salvaged from nests showed that 2378-TCDD levels were about three times higher in 1987 than in 1986. At a colony in Vancouver, 2378-TCDF levels were significantly higher in 1987 than 1986 eggs. Levels of organochlorine pesticides and total mercury in eggs were generally low; highest residue levels were found in two mainland colonies, particularly at one adjacent to an agricultural area. Total PCB levels were low and did not differ significantly among locations. Analysis of PCB congener ratios indicated different sources of PCBs. Regurgitated prey samples collected in 1986 from four locations had generally low levels of PCDD, PCDF, mercury, lead and cadmium contamination.

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Intrusive images have been reported to occur in a broad range of people with posttraumatic stress disorder, but the frequency of intrusive auditory perceptions has rarely been addressed. This study compared five posttraumatic stress disorder veterans experiencing auditory hallucinations with 31 nonhallucinating veterans on demographic, military, postmilitary, and symptom variables. Veterans who reported auditory hallucinations had higher combat exposure and more intense posttraumatic stress disorder symptoms than the other veterans. These veterans also tended to be more refractory to treatment than veterans with no hallucinations. Clinical vignettes of the veterans with auditory hallucinations are given, and the implications of the results for a subgroup of chronic posttraumatic stress disorder veterans are discussed.

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Epidemiologic knowledge of hepatitis D virus (HDV) infection is limited. A seroepidemiologic study was undertaken to determine the prevalence of the infection in Newfoundland and Labrador. Between October 1983 and October 1985 over 200 people were recognized through routine serodiagnosis and screening as having hepatitis B seromarkers. A total of 223 serum samples from 186 of these people were tested for anti-HDV. The subjects were mainly asymptomatic carriers of hepatitis B surface antigen or patients with acute or chronic hepatitis B from the native Indian and Inuit and the non-native populations. None of the serum samples were positive for anti-HDV. The absence of anti-HDV in a substantial number of people in the province who are infected with hepatitis B virus is strong evidence that HDV infection is not prevalent in the local population, including native people.

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An outbreak of folliculitis caused by Pseudomonas aeruginosa serotype O:7 occurred among the guests of a hotel in St. John's, Newfoundland, Canada, and the source of the infection was traced to the hotel whirlpool. Of 36 persons who used the whirlpool, 26 (72%) developed folliculitis within 1 to 5 days after exposure; the attack rate was significantly higher for children (90%) than for adults (50%). The rash characteristics were consistent with those of Pseudomonas folliculitis previously described (T. L. Gustafson, J. D. Band, R. H. Hutcheson, Jr., and W. Schaffner, Rev. Infect. Dis. 5:1-8, 1983). This is considered to be the first outbreak in which P. aeruginosa serotype O:7 has been incriminated. Published reports to date of outbreaks of Pseudomonas folliculitis associated with the use of whirlpools, hot tubs, swimming pools, etc., were reviewed.

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Ablation of the adrenal glands potentiates analgesia induced by morphine and attenuates an opioid form of stress-induced analgesia. the adrenal cortex has been implicated in analgesia induced by morphine and enkephalin-like peptides in the adrenal medulla have been suggested to modulate stress-induced analgesia. The effect of adrenalectomy upon analgesia produced by stimulation of the brain has not been investigated. The present investigations demonstrated that antinociception (measured with the tail-flick test) from focal stimulation of the periaqueductal grey was attenuated or abolished after adrenal ablation. These results implicate adrenal hormones in the regulation of the endogenous pain inhibitory system in the brain.

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