Search PubMed⌕ Search

Biomedical subjects

J L Jackson

Publications and source records attributed to J L Jackson.

At least 55 records · Page 3Linked to original sources

Depressive and anxiety disorders in patients presenting with physical complaints: clinical predictors and outcome.

PURPOSE: To identify the predictors of depressive and anxiety disorders in general medical patients presenting with physical complaints and to determine the effect of these mental disorders on patient outcome. PATIENTS AND METHODS: In this cohort study, 500 adults presenting to a general medicine clinic with a chief complaint of a physical symptom were interviewed with PRIME-MD to diagnose DSM-IV depressive and anxiety disorders. Clinical predictors were identified by logistic regression analysis. Outcomes were assessed immediately postvisit and at 2 weeks and 3 months. These included symptomatic improvement, functional status, unmet expectations, satisfaction with care, clinician-perceived patient difficulty, and health care utilization and costs. RESULTS: A depressive or anxiety disorder was present in 146 (29%) of the patients. Independent predictors of a mental disorder included recent stress, multiple physical symptoms (ie, 6 or more), higher patient ratings of symptom severity, lower patient ratings of their overall health, physician perception of the encounter as difficult, and patient age less than 50. Patients with depressive or anxiety disorders were more likely to have unmet expectations postvisit (20% versus 8%, P < 0.001), be considered difficult (26% versus 11%, P < 0.0001), and report persistent psychiatric symptoms and ongoing stress even 3 months following the initial visit. Psychiatric status was not associated with symptomatic improvement, health care utilization, or costs. CONCLUSION: Simple clinical clues in patients with physical complaints identify a subgroup who may warrant further evaluation for a depressive or anxiety disorder. Such disorders are associated with unmet patient expectations and increased provider frustration.

Adult↗

Kainic acid lesions enhance locomotor responses to novelty, saline, amphetamine, and MK-801.

Intracerebroventricular (i.c.v.) administration of kainic acid (KA) to rats produces neuronal loss in the hippocampus and other areas of the limbic system. The present study demonstrates that i.c.v. KA enhances the locomotor response to novelty and saline injection, as well as to amphetamine and MK-801. Sixteen to 18 days after i.c.v. administration of KA or vehicle, lesioned and control rats were placed in a novel cage, and locomotor activity and grooming were recorded for 30 min prior to and 60 min following a subcutaneous injection of saline, D-amphetamine, or MK-801. In response to the novel cage and after each injection, KA rats exhibited increased locomotor activity relative to controls. Grooming behavior was found to be elevated in the KA rats when compared to controls, but only in response to the novel cage and saline injection. The possibility that damage to the limbic system disrupts dopaminergic regulation of locomotor behavior is discussed, as well as implications for neuropathology in schizophrenia.

Animals↗

Patient satisfaction and quality of care.

As the Department of Defense initiates Tricare, its new system of integrated health delivery, outcome assessment will become increasingly important. Traditional outcomes have focused on disease and its more serious consequences, disability and death. Patient satisfaction is only recently emerging as an important measure of the quality of health care delivery. In this paper, we focus on patient satisfaction, exploring its historical roots, its evolution as an outcome measure, and its potential utilities and weaknesses in quality assessment.

Humans↗

Focussing on aging: an electrophysiological exploration of spatial and attentional processing during reading.

Three types of selective attention tasks were presented to 24 young (20.5 years) and 24 middle-aged (57.5 years) participants. The major aim of the experiment was to explore three different aspects of selective attention, namely a pre-attentive level (i.e. auditory passive oddball task), an attentive level using spatial attention in a memory search task (i.e. selective search task) and an attentive level using a spatial cue to select a word in a reading-like situation (i.e. selective language task). The data showed that the mismatch negativity was not affected by aging although the ERPs indicated that the younger participants were paying more attention to the tones than the middle-aged. The selective search task data showed that spatial selective attention is only mildly affected by aging. The ERP-data seemed to indicate that irrelevant stimuli had a smaller impact in the middle-aged. The selective language data showed a look-a-like effect of flanker words for both age groups although the effect in the middle-aged was delayed by 30 ms and smaller. It was theorized that flankers might have smaller impact in the middle-aged. N400 was found to be smaller and delayed (90 ms) in the middle-aged participants. The overall conclusion on the basis of the three experiments is that the selectivity of processing was preserved or even enhanced in our particular group of middle-aged participants.

Adult↗

The Dutch health care system: lessons for reform in the United States.

The Dutch health care system achieves universal access with high-quality outcomes at a cost below that in the United States. As US policy makers struggle with issues regarding access, quality, and cost, scrutiny of successful systems in other nations may be useful. Review of health care in the Netherlands and contrast with that in the United States offer lessons of potential use in US health care reform.

Delivery of Health Care↗

Platelet paroxetine binding in major depressive disorder with and without comorbid obsessive-compulsive disorder.

Platelet 3H-paroxetine binding measures were compared in three age-matched groups each containing 11 individuals: a group with DSM-III-R major depressive disorder (MDD) and comorbid obsessive-compulsive disorder (OCD), a group with DSM-III-R MDD alone, and a psychiatrically screened normal comparison group. No differences were found between groups in Bmax values. The patients with MDD only were found to have significantly higher Kd values than either the group with comorbid OCD or the normal subjects. No significant correlations were found between binding measures and either depressive or OCD symptoms. Our data suggest that inconsistencies remain in the literature on 3H-imipramine binding in OCD and that a variety of confounding factors may explain them. Duration of illness, for example, may be one such factor as decreases in uptake site number tend to dissipate with longer duration of illness.

Adult↗

Platelet serotonin markers and depressive symptomatology.

Dysfunction of brain serotonergic symptoms may be a factor in the mood and behavioral disturbances associated with depression. Platelet serotonin measures represent indirect but easily obtainable indices of brain serotonin function. To examine the specificity of relationships between cognitive and vegetative symptom groupings and platelet serotonin measures, we assessed 35 depressed outpatients using the Hamilton Rating Scale for Depression and collected platelets after a minimum 3-week drug-free period. Platelets were also collected from 14 controls. The results showed that depressed patients had lower platelet serotonin (5-HT) uptake site density values than controls and that 5-HT uptake site density values were inversely correlated with the severity of cognitive symptoms of depression. Platelet 5-HT2 receptor density values were higher in depressed patients than controls, and there was a trend toward a direct correlation between the cognitive symptoms of depression and 5-HT2 receptor density values. Neither platelet measure showed any relationship with the severity of the vegetative symptoms of depression.

Adolescent↗

Comparison of acute alprazolam (0.25, 0.50 and 1.0 mg) effects versus those of lorazepam 2 mg and placebo on memory in healthy volunteers using laboratory and telephone tests.

This study was designed to confirm the hypothetical dose-dependent effect of alprazolam on memory and to compare its effects on tests measuring different aspects of cognitive and psychomotor functioning. A secondary purpose was to compare the sensitivity of newly developed telephone tests with a standard laboratory test of memory. Twenty healthy male volunteers (aged 18-35 years) participated in a five-way double-blind crossover design. Treatments were single oral doses of alprazolam (0.25, 0.5 and 1.0 mg), placebo and lorazepam 2.0 mg. The latter was included as an internal control for demonstrating sensitivity of the method. Lorazepam significantly impaired all performance measures except two: verbal fluency and accuracy of music recognition were insensitive to drug effects. Alprazolam had clear dose-dependent effects on different aspects of memory: 0.25 mg did not affect any parameter; 0.5 mg impaired performance in a Word Learning Test and a Spatial Memory Test and also psychomotor performance; 1.0 mg additionally impaired Syntactic Reasoning, Semantic Verification, and Critical Flicker Fusion performance. Alprazolam's effects were not selective for any of the cognitive functions as measured in this study. The telephone tests were clearly less sensitive than the standard test, though sufficient for showing significant effects of alprazolam 1 mg and lorazepam 2 mg.

Adolescent↗

Kainic acid decreases hippocampal neuronal number and increases dopamine receptor binding in the nucleus accumbens: an animal model of schizophrenia.

Intracerebroventricular (i.c.v.) administration of kainic acid (KA) produces graded neuronal loss in the hippocampus and other regions of the medial temporal lobe. Many of these brain regions send excitatory projections to the nucleus accumbens, a dopaminergic brain area implicated in psychotomimetic and antipsychotic drug action. In the present study, neurochemical function in the nucleus accumbens and anterior caudate-putamen was examined one week after i.c.v. administration of 1.5, 4.5, or 6.6 nmol of KA. As expected, i.c.v. KA produced dose-dependent neuronal loss in the dorsal and ventral hippocampus. Extrahippocampal neuronal loss was also observed in the thalamus and piriform cortex in some of the KA-treated rats. While ambient levels of dopamine turnover and excitatory amino acids in the nucleus accumbens were unaltered by KA, administration of the highest KA dose elevated [3H]spiperone binding exclusively in the accumbens. Finally, behavioral hyperactivity was observed in KA-treated rats over a five-week period following i.c.v. administration. The pattern of neuronal loss, receptor upregulation, and behavioral hyperactivity found after i.c.v. KA administration may provide a useful animal model of the limbic neuropathology and neurochemical dysfunction associated with schizophrenia.

Animals↗

Language, memory, and aging: an electrophysiological exploration of the N400 during reading of memory-demanding sentences.

Twenty-four young and 24 middle-aged academics carried out a language recognition task in which sentences were presented that made either a high or a low demand on working memory (WM). The sentences ended either normally (i.e., congruent) or with an incongruous word. Middle-aged subjects had smaller WM scores, a marginally slowed down recognition performance, and a smaller and delayed N400 component. The event-related potential (ERP) difference between congruent and incongruent endings was smaller in the high-load condition for younger subjects and totally disappeared for the middle-aged subjects. ERPs for all subjects showed a WM-related positivity in the middle of the sentence and a WM-related negativity at the sentence ending. These shifts could be associated with either storage and retrieval processes or with clause wrap-up processes. Most ERP-effects were dependent on WM capacity. Age differences in sentence processing are not simply explained by age itself but depend to a large extent on individual memory capacity.

Adult↗

Adult Kawasaki disease. Report of two cases treated with intravenous gamma globulin.

There are 36 reports in the English-language literature of Kawasaki disease in adults. We present two additional cases, in one of which retinal vasculitis developed, a previously unreported complication antemortem. We report the first use of intravenous gamma globulin in the United States for treatment of adult-onset Kawasaki disease and review the pertinent literature.

Adolescent↗

Visual spatial attention to stimuli presented on the vertical and horizontal meridian: an ERP study.

In the first experiment, 48 subjects carried out a visual spatial attention task. Stimuli were presented at the vertical meridian, either above or below a fixation dot, and the subjects were instructed to attend to one of these stimulus positions and ignore the other position. In three different conditions, the distances between stimulus positions and fixation were 0.5 degrees, 0.9 degrees, and 1.3 degrees. Subjects searched for the presence of prememorized target letters at the attended location: memory load was one or four items in different conditions. The P1/N1 enhancement typically found on the horizontal dimension was not observed on the vertical dimension. Instead, a positive shift of the attended compared with the unattended stimuli was found, which was most prominent at anterior electrodes. This positivity showed effects of the distance manipulation. The N2b-P3a effects of attention and the effect of memory load (search negativity) normally present in this kind of selective search task were also found. Reaction times were faster when attention was directed above fixation than when it was directed below fixation. The event-related potential data suggested that this difference could be attributed to a more efficient neglecting of irrelevant stimuli presented below fixation. In Experiment 2, we examined whether the absence of the P1/N1 enhancement as the result of spatial attention in Experiment 1 could be attributed to (a) the presentation of stimuli along the vertical meridian instead of along the horizontal meridian, (b) the use of midline electrodes instead of lateralized electrodes, and (c) the relatively small spatial separation between the relevant and irrelevant stimuli. Twelve subjects searched for the presence of a single target letter at an attended position in three different conditions. In two of the conditions the letters were presented to the left or right of fixation. The distance between fixation and the stimulus positions was 1.3 degrees in one of these conditions and 3 degrees in the other condition. In the third condition, the stimuli were presented at 3 degrees above or below fixation. In all three conditions effects similar to those in Experiment 1 were observed. In addition, in all three conditions an enhancement of the P1 and N1 components was found at two lateral occipitotemporal electrodes.

Adolescent↗

Focusing on the N400: an exploration of selective attention during reading.

In a series of two experiments, subjects read sentences wherein words were flanked in the lower visual field by irrelevant words (i.e., flankers). The visual angle between the words in the sentence and the flanker words was manipulated (i.e., 0.57 degrees, 0.97 degrees, 1.37 degrees). Sentence endings were either congruent or incongruent; incongruent endings elicited a large N400 component. Flanker effects were observed for sentence final words on electrophysiological measures during the reading task and on subsequent recognition memory performance for sentence final and new words. For both measures, the flanker effect interacted with the congruency of the sentence ending as well as the visual angle between the sentence final word and its flanker. The largest and earliest flanker effects were observed for congruent endings at the smallest visual angle (0.57 degrees); congruent endings and flankers in intermediate visual angle (0.97 degrees) conditions displayed a similar flanker-related negativity but with a longer onset latency (490 vs. 280 ms). Congruent endings and their flankers in the largest visual angle (1.57 degrees) conditions revealed no flanker effect.

Adult↗

Testing the effects of hypnotics on memory via the telephone: fact or fiction?

The two benzodiazapines used in this experiment, namely midazolam and flunitrazepam, have both been shown to have effects on memory processing in laboratory studies. In spite of the potential hazards involved in real life testing, it should be possible to replicate such findings in everyday environments and it is argued that a successful replication would be a very meaningful extension to the existing laboratory data. The present study was successful in producing significant "hangover" effects in healthy volunteers using a novel "user-friendly" telephone testing technique. Compared to placebo, the two hypnotics reduced speed of processing in tasks which required retrieval from long-term semantic memory (semantic verification) and the manipulation of material in working memory (syntactic reasoning). We suggest that this new method offers the potential for carrying out large-scale psychopharmacological studies with real patients and achieves a meaningful step forward in the search for ecological validity.

Adult↗

An electrophysiological study of semantic processing in young and middle-aged academics.

This study explored age differences in the N400 component, described by Kutas and Hillyard as an index of semantic expectancy. A group of young students and a group of middle-aged academics read a number of congruent and incongruent sentences followed by a recognition task. Age differences were found in both accuracy and speed in the recognition task. The N400 elicited in the reading task was both delayed in latency and reduced in amplitude in the older group. These aging effects could not be attributed to early stimulus input processes because the N1 did not differ between the age groups. A re-averaging of the event-related potentials during reading as a function of subsequent recognition showed a small memory-related positivity for the younger group and a large memory-related positivity for the older group, suggesting a difference in the encoding strategies of the two groups. To check the generalizability of the results of this particular age group, a further task (a memory scanning task) was carried out. The results, a delayed P3b and an increased reaction time, matched those found in the literature.

Adult↗

Phorbol ester induces phosphorylation of the 80 kilodalton murine interleukin 1 receptor at a single threonine residue.

The cytoplasmic domains of some cell surface receptors become phosphorylated in cells treated with phorbol esters. The present study was undertaken in order to determine whether this is also true of the 80 kDa interleukin 1 receptor (IL1R). Recombinant murine IL1R, transfected into chinese hamster ovary (CHO) cells or murine fibroblasts, was immunoprecipitated from [32P]orthophosphate-labelled cells. IL1R phosphorylation was only detected in cells pretreated with phorbol 12-myristate 13-acetate (PMA) and occurred solely on phosphothreonine. In contrast to a previous report, little or no IL1R phosphorylation occurred in response to IL1. By using a truncated receptor and receptors in which threonine residues were changed to alanines, we established that Thr537, near the carboxy-terminus, is the major site of PMA-induced phosphorylation. The human IL1R has a different sequence at this locus, and is apparently not phosphorylated. Binding studies showed that PMA-induced phosphorylation had no discernible effect on ligand binding or internalization.

Amino Acid Sequence↗

Assessment of schizophrenic inpatients with the MCMI.

The Million Clinical Multiaxial Inventory (MCMI) Psychotic Thinking scale previously was found insensitive in the detection of schizophrenia. The MCMI also was shown to be susceptible to undetected "faking good." We hypothesized that the insensitivity of the MCMI Psychotic Thinking scale was due to an unwillingness of schizophrenic patients to report psychotic symptoms. The MCMI was administered to 258 male schizophrenic inpatients who were classified as symptom-reporters or nonreporters based upon whether they endorsed psychotic symptoms on a separate problem checklist. Willingness to report psychotic symptoms was a significant factor in MCMI Psychotic Thinking scale scores as well as many other MCMI scales.

Adult↗