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J Gorman

Publications and source records attributed to J Gorman.

At least 19 recordsLinked to original sources
PubMed1999

SPECT study of visual fixation in schizophrenia and comparison subjects.

BACKGROUND: The consistent association of impaired eye movements and schizophrenia suggests a relationship between the neurobiology of the illness and visual pursuit systems. Visual fixation (VF), an eye "movement" task at zero velocity, is the simplest such abnormality in schizophrenia patients and their relatives. METHODS: We used a VF task for a functional imaging study. Six neuroleptic-free schizophrenia patients and eight gender and mean age matched comparison subjects had SPECT scans with 20 mCi of Tc99-HMPAO, during VF on a simple blue line intersection. MEDX data saved in ANALYZE format for SPM 95 was used to generate paired t-test statistical data for display in Talairach space, with rCBF changes given as Z-scores. RESULTS: Patients, compared to controls, had increased rCBF in both the parahippocampal gyrus (bilaterally) and in the right fusiform gyrus. They had decreased rCBF in the left frontal cortex, including medial and superior frontal gyri and anterior cingulate. Overall, compared to controls, patients had medial temporal lobe hyperperfusion along with left prefrontal hypoperfusion. CONCLUSIONS: These findings are consistent with the hypothesized imbalance between the medial temporal and frontal lobes that is postulated for schizophrenia. It was of interest that the relative rCBF differences between schizophrenia patients and controls in this small sample were observable with this cognitively non-demanding visual fixation task.

Adult↗
PubMed1999

Left temporal lobe dysfunction in schizophrenia: event-related potential and behavioral evidence from phonetic and tonal dichotic listening tasks.

BACKGROUND: Asymmetric reduction of the P3 event-related potential (ERP) has provided evidence of left temporal lobe dysfunction in schizophrenia. Prior studies have been limited by reliance on simple target detection (oddball) tasks with pure tones. This study investigated the time course and topography of ERPs to binaural syllables or complex tones in dichotic listening tasks. METHODS: Event-related potentials of 26 patients meeting criteria for schizophrenia (n = 19) or schizoaffective disorder (n = 7) and 26 healthy controls were recorded from 30 scalp electrodes during 2 dichotic tasks in which different syllables or complex tones were simultaneously presented to each ear. A principal components analysis was used to derive factor scores corresponding to overlapping components in ERP waveforms--N1, N2, P3, and a late-positive potential. RESULTS: Healthy controls showed a right ear advantage for perceiving dichotic syllables, which was associated with greater N2 amplitude at left than right temporoparietal sites. Patients with schizophrenia did not show either this perceptual or N2 asymmetry. Patients also had smaller late-positive potential amplitude when compared with controls for both syllables and complex tones, with greatest decrement over left temporal sites. CONCLUSIONS: A right ear advantage in healthy adults for perceiving consonant-vowels was associated with a left-lateralized ERP component peaking at 200 milliseconds after syllable onset (N2). Patients with schizophrenia failed to show either of these task-dependent asymmetries, which may indicate a dysfunction of left temporal regions involved in phonetic classification. A task-independent asymmetric reduction of a later positive potential in patients with schizophrenia resembled left temporal P3 reductions reported for auditory oddball tasks.

Acoustic Stimulation↗
PubMed1998

Psychobiological heterogeneity of familial and sporadic schizophrenia.

BACKGROUND: Although schizophrenia is presumed to be heterogeneous, there has been limited success distinguishing familial from sporadic cases. We used psychobiological measures to examine heterogeneity, as they may be closer to neurobiology than symptoms. Smooth pursuit eye movement quality (SPEM) and dichotic listening (DL) tests to tones and words were used to assess hemispheric laterality asymmetry. METHODS: Forty-six research unit patients participated in assessments of family history (FH) and physiological measures. FH was categorized by three exclusive groups: FH-1 patients had a chronic schizophrenia-related psychosis in a first-degree relative, FH-2 had it in second-degree relative, and FH-3 had no family member with a reoccurrence. RESULTS: Analysis of variance showed a significant group difference for SPEM and DL tones. SPEM was significantly worse in all three schizophrenia groups than for the normal comparison subjects. Among the schizophrenia groups, the nonfamilial group (FH-3) had the worst SPEM quality, FH-2 had intermediate quality, and FH-1 had the best quality. Conversely, only the nonfamilials (FH-3) had normal right hemispheric lateralization for tones, whereas familials did not, and FH-2 again had intermediate values. The lateralization quotient for DL words did not significantly differ among the groups. CONCLUSIONS: SPEM was affected most in sporadic, not familial schizophrenia, whereas dichotic listening was most affected in familial schizophrenia. This double dissociation supports the utility of the familial/sporadic distinction and suggests that etiological factors in different forms of schizophrenia may impact principally on distinct neurobiological substrates, despite similar patient phenomenology.

Adult↗
PubMed1998

The time course of visuospatial processing deficits in schizophrenia: an event-related brain potential study.

Event-related brain potentials (ERPs) were recorded during a dot enumeration task so as to investigate electrophysiologic correlates of early visuospatial processing in schizophrenia. Twenty-eight patients having a diagnosis of schizophrenia (n = 19) or schizoaffective disorder (n = 9) and 28 controls were tested. Patients showed poorer dot enumeration than did controls and also had markedly reduced early negative ERPs, which began about 150 ms after stimulus onset at the peak of the N1 potential and reached its maximum about 275 ms at the N2 peak. The N1 reduction in patients was greatest over left parietal sites for stimuli in the right visual field. The marked N1 and N2 reductions in patients are supportive of models postulating deficits in early visuospatial attention and allocation of conceptual resources in schizophrenia.

Adult↗
PubMed1997

Diminished cardiac vagal tone in schizophrenia: associations to brain laterality and age of onset.

We measured high-frequency (rapid) heart rate variability (HRV) from 24-hour Holter electrocardiograms to index cardiovagal tone in 23 patients with DSM-III-R schizophrenia or schizoaffective disorder. High-frequency HRV, quantitated by measuring the percent of successive normal interbeat intervals greater than 50 msec (PNN50), demonstrated a bimodal distribution: 11 of 23 patients had a PNN50 of > and = 8.0 (mean value = 17.7 +/- 11.0), and 12 had a PNN50 of < and = 4.0 (mean value = 1.8 +/- 1.0); no subject had a PNN50 value between 4.0 and 8.0. All 12 low cardiovagal tone patients (versus only 6/11 of the other patients) had a schizophrenia (not schizoaffective) diagnosis (p = .013). PNN50 was not associated with present age, gender, smoking, IQ scores, or symptomatology, but patients with lower cardiovagal tone did have a significantly later age of onset (20.5 +/- 5.3 vs. 14.8 +/- 2.8 years: p = .005). PNN50 subgroups also differed on dichotic listening measures of brain laterality. The low group failed to show left ear (right hemisphere) advantage for complex tones seen in the other patients and normal adults. They also showed larger right ear (left hemisphere) advantage for dichotic words than the other patients. This evidence of relative right hemisphere disadvantage in patients with low cardiovagal tone is consistent with findings linking autonomic nervous system and right hemisphere function. These findings also support the existence of subgroups of schizophrenia patients differing in autonomic activity, brain laterality, and clinical features.

Adult↗
PubMed1997

Risperidone in adolescents with schizophrenia: an open pilot study.

OBJECTIVE: To assess critically the short-term efficacy and safety of risperidone in adolescents with schizophrenia. METHOD: Subjects were adolescents who were attending a research day hospital as outpatients and who had received a diagnosis of schizophrenia. This was an open pilot study; after a 2-week washout period during which all psychotropic medications were gradually discontinued, subjects were treated with risperidone for 6 weeks. Dosage was regulated individually over a period of 3 weeks; starting dose was 2.0 mg/day followed by 1.0-mg increments every 2 days; maximum dose was not to exceed 10 mg/day. The main outcome measures included the Positive and Negative Syndrome Scale of Schizophrenia, the Brief Psychiatric Rating Scale, and the Clinical Global Impression. RESULTS: Ten adolescents between 11 and 18 years of age were enrolled in the study. Risperidone produced clinically and statistically significant improvement on the Positive and Negative Syndrome Scale for Schizophrenia. Brief Psychiatric Rating Scale, and Clinical Global Impression at doses ranging from 4.0 mg/day to 10.0 mg/day (mean = 6.6). There were no major adverse reactions associated with risperidone use. CONCLUSIONS: Risperidone appears to have been effective and well tolerated in this sample of adolescents with schizophrenia.

Adolescent↗
PubMed1997

Oral candidiasis in HIV infection: predictive value and comparison of findings in injecting drug users and homosexual men.

The objectives of this study were to compare the relationship of oral candidiasis to HIV status, cohort and CD4+ lymphocyte values in injecting drug users and homosexual men and to examine its impact on prognosis. An oral examination was added to an ongoing longitudinal study of HIV infection. Data obtained at 6-month intervals included smoking, illicit drug use, medication use, symptoms and medical diagnoses, physical examination findings and laboratory data. In this study HIV+ subjects were much more likely to present with oral candidiasis than were HIV- subjects (OR = 6.3, P < 0.01). Injecting drug users, regardless of serostatus, were more likely than homosexual men to present with oral candidiasis (OR = 3.0, P = 0.001). In both cohorts oral candidiasis was associated with low CD4+ lymphocyte counts and percent ages, and Kaplan-Meier survival estimates showed that subjects with oral candidiasis had a poorer prognosis than those without candidiasis, even after controlling for CD4+ lymphocyte count.

AIDS-Related Opportunistic Infections↗
PubMed1997

The absence of the transcription activator TFE3 impairs activation of B cells in vivo.

TFE3 is a ubiquitously expressed member of the TFE3/mi family of basic helix loop helix zipper transcription factors. TFE3 binds to muE3 sites located in the immunoglobulin heavy-chain (IgH) intronic enhancer, heavy-chain variable region promoters, the Ig kappa intronic enhancer, and regulatory sites in other genes. To understand the role of TFE3 in Ig expression and lymphoid development, we used embryonic stem (ES) cell-mediated gene targeting and RAG2-/- blastocyst complementation to generate mice which lack TFE3 in their B and T lymphocytes. TFE3- ES cells fully reconstitute the B- and T-cell compartments, giving rise to normal patterns of IgM+ B220+ B cells and CD4+ and CD8+ T cells. However, TFE3- B cells show several defects consistent with poor B-cell activation. Serum IgM levels are reduced twofold and IgG and IgA isotypes are reduced three- to sixfold in the TFE3- chimeras even though in vitro, the TFE3- splenocytes secrete normal levels of all isotypes in response to lipopolysaccharide activation. Peripheral TFE3- B cells also show reduced surface expression of CD23 and CD24 (heat-stable antigen).

Alleles↗
PubMed1996

Nursery.

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Color↗
PubMed1995

Difference in clinical implications of CD4 counts among HIV-infected homosexual men and injection drug using men and women.

While the relationship between CD4 counts and clinical symptoms is well established among homosexual men, the same is not true for injection drug using men and women (IDUM and IDUW). In this paper we investigate whether CD4 counts have the same clinical implications for IDUM and IDUW as for homosexual men. We estimated the CD4 counts at which 50 per cent of the HIV-infected but AIDS-free population has AIDS related complex (ARC) based on three biannually measured CD4 counts. The analyses involve interval, right and left censored threshold data. We took the parametric approach, assuming that the threshold values for ARC arise from a family of distributions that includes symmetric, left or right skewed distributions, in which the logistic and extreme value distributions are embedded as special cases. The resulting estimates of median thresholds of CD4 counts for ARC were 249, 424 and 755 for homosexual men, IDUM, and IDUW, respectively. The results were robust with respect to the assumptions on the underlying distribution.

AIDS-Related Complex↗
PubMed1995

Cerebral single-photon emission computed tomography abnormalities in human immunodeficiency virus type 1-infected gay men without cognitive impairment.

OBJECTIVE: To determine whether technetium Tc99m exametazime single-photon computed emission tomography (SPECT) can distinguish gay human immunodeficiency virus (HIV)-positive subjects, both with and without mild cognitive impairment, from gay HIV-negative control subjects. DESIGN: Twenty HIV-positive subjects (12 without cognitive impairment and eight with mild cognitive impairment) and 10 HIV-negative subjects underwent neurological, neuropsychological, magnetic resonance imaging, and technetium Tc 99m exametazime SPECT examinations. SETTING: Subjects were recruited from a natural history study of gay men with HIV infection. PATIENTS: Subjects from the cohort who had previously participated in a magnetic resonance imaging study were selected for the SPECT study. MAIN OUTCOME MEASURES: The SPECT scans were rated as abnormal if focal defects, confirmed by a horizontal profile analysis, were seen. RESULTS: Sixty-seven percent of HIV-positive subjects without cognitive impairment, 88% of HIV-positive subjects with mild cognitive impairment, and 20% of HIV-negative subjects had abnormal SPECT scans (P < .05 for both HIV-positive groups when each group was compared with HIV-negative subjects). CONCLUSION: Compared with gay HIV-negative control subjects, focal SPECT defects are seen with an increased frequency in HIV-positive gay men without cognitive impairment and in HIV-positive gay men with mild cognitive impairment.

AIDS Dementia Complex↗
PubMed1995

A comparison of cerebral SPECT abnormalities in HIV-positive homosexual men with and without cognitive impairment.

OBJECTIVE: To determine whether technetium Tc 99m exametazime (HMPAO) single-photon emission computed tomography (SPECT) can distinguish between human immunodeficiency virus (HIV)-positive homosexual men with normal neuropsychologic test results and HIV-positive homosexual men with abnormal neuropsychologic test results. DESIGN: Neurologic, neuropsychologic, magnetic resonance imaging, and Tc 99m HMPAO SPECT examinations were performed on 10 HIV-positive homosexual men without cognitive impairment and five HIV-positive homosexual men with cognitive impairment. PATIENTS: Human immunodeficiency virus-positive homosexual men from New York City were recruited for the study. MAIN OUTCOME MEASURES: Findings on SPECT scans were evaluated qualitatively for focal defects, heterogeneity of the cortical margin, white matter hypoperfusion, and decreased global cortical uptake. All SPECT focal defects were coregistered with magnetic resonance images; SPECT heterogeneity and global cortical uptake were also measured quantitatively. RESULTS: Coregistration with magnetic resonance imaging revealed that 63% of the focal SPECT defects corresponded to brain gyri and 37% corresponded to sulci. There was no significant difference in the frequency of qualitative or quantitative SPECT abnormalities between HIV-positive homosexual men ith and without cognitive impairment. However, after examining individual neuropsychologic test factors, impaired motor speed performance was associated with decreased quantitative global cerebral uptake. CONCLUSIONS: Qualitative SPECT abnormalities are not increased in frequency in HIV-positive homosexual men with global cognitive impairment compared with those in HIV-positive homosexual men without cognitive impairment. Impaired motor speed performance may be associated with decreased quantitative global cerebral uptake.

Adult↗
PubMed1995

Neuropsychological changes in a prospectively followed cohort of homosexual and bisexual men with and without HIV infection.

We evaluated neuropsychological test performance of 168 homosexual and bisexual men with and without human immunodeficiency virus (HIV) infection (113 HIV+ subjects and 55 HIV- controls) over 4.5 years of semiannual follow-up. Analyses of the longitudinal data were performed by applying generalized estimating equations (GEEs) to regression analyses with repeated measures. Compared with the HIV- men, the HIV+ subjects performed more poorly on memory testing. Performance on all tests tended to improve over time, but this improvement was attenuated or eliminated in the HIV+ group for tests of language and attention. Within the HIV+ subjects, improvement over time in tests of memory, executive function, language, and attention was attenuated or eliminated in patients with lower CD4 levels; more advanced HIV disease was associated with poorer memory and executive function and with attenuated or reduced learning effects for memory, motor speed, and language tests. Clinically significant neurologic findings were associated with worse memory and orientation and with attenuated or reversed learning effects for memory, language, and attention tests. There were 33 deaths in the HIV+ group. In the men who died, there was more rapid decline in executive, language, and attentional test performance. These observations remained significant after controlling for HIV disease severity. We conclude that HIV infecting the CNS results in progressive cognitive change that is closely associated with neurologic findings. In addition, our findings suggest a relation between more rapid cognitive progression and death.

Adult↗
PubMed1995

Toward a 21st century quality-measurement system for managed-care organizations.

As the Nation's largest managed-care purchaser, the Health Care Financing Administration (HCFA) is working to develop a uniform data and performance-measurement system for all enrollees in managed-care plans. This effort will ultimately hold managed-care plans accountable for continuous improvement in the quality of care they provide and will provide information to consumers and purchasers to make responsible managed-care choices. The effort entails overhauling peer review organization (PRO) conduct of health maintenance organization (HMO) quality review, pilot testing a new HMO performance-measurement system, establishing criteria for Medicaid HMO quality-assurance (QA) programs, adapting employers' HMO performance reporting systems to the needs of Medicare and Medicaid, and participation in a new alliance between public and private sector managed-care purchasers to promote quality improvement and accountability for health plans.

Capitation Fee↗
PubMed1995

Effect of recombinant human erythropoietin on hospitalization of hemodialysis patients.

The effect of recombinant human erythropoietin (EPO) on hospitalization of patients with end-stage renal disease (ESRD) was evaluated in a controlled clinical trial. A cohort of 67 new hemodialysis patients prescribed EPO shortly after the clinical availability of EPO were the treatment group. The control group was a cohort of 67 new hemodialysis patients matched for clinical center, age, cardiovascular disease and transfusion history. These patients had not been prescribed EPO as they had started hemodialysis prior to the clinical availability of EPO. There were 21 pairs without hospitalization and 46 pairs with at least 1 member of the pair experiencing hospitalization. Among the latter group, the median follow-up was 174 and 184 days for the EPO and control patients respectively. For all hospitalizations, those treated with EPO were hospitalized 15.3 days per year compared to 23.2 days for the control patients. The difference (EPO-control) was -7.9 days (95% CI: -21.0; 7.8) for all cause hospitalization. For hospitalizations due to cardiac, infectious disease and gastrointestinal disease, the differences were 1.6, 1.8 and 1.2 days favouring EPO treated patients. For hospitalizations related to vascular access complications, the difference was 0.9 days favoring the control group. All other causes favoured EPO treated patients by 4 days. There had been 58 hospitalizations in the EPO group compared to 97 in the control group. The mean duration of hospitalization was 8.0 days for the EPO and 9.6 for the control group. The direction and magnitude of the change in all cause hospitalization represents an improvement in morbidity and an important decrease in health resource utilization.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗