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D Friedman

Publications and source records attributed to D Friedman.

At least 145 records · Page 8Linked to original sources
PubMed1992

Event-related potential correlates of repetition priming and stimulus classification in young, middle-aged, and older adults.

Electrophysiological and behavioral measures were concurrently recorded from young, middle-aged, and elderly subjects during two classification tasks that required different levels of processing. In both tasks, a portion of stimuli repeated after lags of 2, 8, and 32 intervening items following their first presentation, although these repetitions were incidental to the primary task. All three age groups showed similar patterns of behavioral and event-related potential (ERP) responses associated with stimulus classification and item repetition. ERPs to repeated words were characterized by greater positive amplitude relative to words at first presentation. Similarly, ERPs elicited by items in a primed category were more positive compared with unprimed items. Reaction times were faster to both repeated and primed items. Behavioral and ERP effects were more marked when subjects were required to discriminate items based on meaning rather than on orthography. This study supports previous behavioral evidence suggesting that processes associated with repetition priming and stimulus classification are preserved with age, and demonstrates that ERPs are responsive to repetition throughout the life cycle. Implications for the cognitive processes underlying repetition effects are also discussed.

Adult↗
PubMed1992

A developmental event-related potential study of picture matching in children, adolescents, and young adults: a replication and extension.

Event-related potentials were recorded in a developmental study of picture matching using an adaptation of Posner's (1978) letter-matching tasks. Subjects ranging in age from 6-39 were asked to decide whether two line drawings, presented sequentially, were the same or different on the basis of physical (physical identity), nominal (name identity), or categorical (category identity) criteria. The amplitude of a negativity at 400 ms (Neg400) increased as the number of dimensions on which the two line drawings differed increased. This effect held for all age groups, and was interpreted as reflecting the degree of semantic and/or physical relationship between the two pictures. However, one finding for Neg400 did suggest a qualitative difference in processing mode between the younger and older subjects. Both Neg400 and P3b latencies showed highly significant linear age trends, decreasing with increasing age. These age-related changes were interpreted as demonstrating quantitative speed of processing differences among age groups. The latencies of both Neg400 and P3b increased as the matching criteria became more complex. Moreover, P3b latency increased as the number of dimensions on which the two pictures differed increased, and this did not interact with age. Although both Neg400 and P3b showed age-related changes in scalp distribution, the fact that each was related to the experimental variables in similar fashion in all age groups suggested that they were homologous components across the age range studied. Taken as a whole, the data support continuity of information processing during these tasks across a wide age range.

Adolescent↗
PubMed1992

Biopsy diagnosis of familial Alexander's disease.

A 26-year-old woman presented with headaches, incoordination and a cerebellar mass (1982). The CT scan revealed dilated ventricles and a hypodense space-occupying lesion adjacent to the fourth ventricle. Neuronal loss, gliosis and masses of Rosenthal fibers were seen in biopsy. There was no evidence of neoplasm. A second biopsy 2 years later was similar to the original specimen. A diagnosis of Alexander's disease was suggested. Later that year the patient's 11-year-old brother manifested a clinical picture initially diagnosed as brainstem glioma, but whose biopsy was characteristic of Alexander's disease. There has been a gradual deterioration of these siblings over the past 6 years (1986-1991). No evidence of neoplasm has appeared.

Adult↗
PubMed1992

Expression and localization of dystrophin in human cardiac Purkinje fibers.

BACKGROUND: Mutations in the dystrophin gene produce clinical manifestations of disease in heart, brain, and skeletal muscle in patients with Duchenne and Beckers muscular dystrophy (DMD/BMD). Conduction disturbances and heart block contribute to cardiac decompensation in these patients, which suggests an important role for dystrophia in the cardiac conduction system. We therefore examined the messenger RNA (mRNA) expression and protein localization of dystrophin in normal human cardiac Purkinje fibers. METHODS AND RESULTS: Polymerase chain reaction amplification of isolated Purkinje fiber complementary DNA identified several alternatively spliced mRNA transcripts encoding for carboxy-terminal isoforms of the dystrophin protein. The predominant mRNA transcript detected was a splice form previously detected in the brain. Antipeptide antibodies specific for a carboxy-terminal dystrophin sequence were used for Western blot analysis and immunocytochemical localization. These antisera detect approximately 400,000-d immunoreactive band or bands on Western blot in normal heart and Purkinje fibers but not in DMD heart. Immunocytochemical staining showed that dystrophin was localized to the membrane surface of the Purkinje fiber. CONCLUSIONS: These results suggest that dystrophin may be an important molecule for membrane function in the Purkinje conduction system of the heart and support the hypothesis that defective dystrophin expression contributes to the cardiac conduction disturbances seen in DMD/BMD:

Base Sequence↗
PubMed1992

Pulling together: building a community debriefing team.

1. Research shows that many emergency workers are affected physically and emotionally by critical incident stress. 2. Debriefings conducted by trained team members are an effective method to mitigate the impact of critical incident stress. A debriefing is a structured, time-limited group intervention. 3. Cooperation among community agencies is essential for the development and effective functioning of a critical incident stress debriefing team. 4. Several teams in Illinois have organized to form a Critical Incident Stress Debriefing Network. The Illinois network is part of an international organization composed of critical incident stress debriefing providers.

Adaptation, Psychological↗
PubMed1992

Influence of age on control of norepinephrine release from the rat tail artery.

Stimulation-evoked norepinephrine release from the rat tail artery increases with age; therefore, the sensitivity of prejunctional alpha-2 adrenergic receptors to antagonists and agonists was compared in perfused tail arteries from Fischer-344 rats, aged 6 and 20 months. The increase in endogenous fractional norepinephrine release produced by blockade of alpha-2 adrenergic receptors with submaximal concentrations of either yohimbine or idazoxan was significantly greater in 6-month-old animals as compared to 20 months; however, the effect of a maximal concentration of idazoxan was not significantly different. Inhibition of norepinephrine release by the alpha-2 receptor agonist UK14304 was reduced in 20-month-old animals compared to 6 months. In contrast, there were no age-related differences in inhibition of contractile responses to nerve stimulation by the prejunctionally acting dopamine D2 agonist, N-0923. These data suggest that age-related changes in the sensitivity of prejunctional alpha-2 receptors to agonists and antagonists may not reflect any fundamental alteration in the function of this receptor system, but may be related to competition between alpha-2 agonists or antagonists and increased biophase concentrations of norepinephrine. This conclusion is supported by lack of an age-related change in function of prejunctional dopamine D2 receptors. Persistence of age-related increases in norepinephrine release when alpha-2 adrenergic receptors are fully blocked may reflect an alteration in other fundamental mechanisms that control norepinephrine release.

Adrenergic beta-Agonists↗
PubMed1991

Variable region gene analysis of pathologic human autoantibodies to the related i and I red blood cell antigens.

To investigate the molecular basis of the autoimmune response to the related i and I carbohydrate antigens, we studied cold agglutinins (CA) from B-cell clones and from the peripheral circulation of patients with lymphoproliferative syndromes. Sequence analyses of expressed variable region genes indicate that both anti-i and anti-I specificities from B-cell clones from two patients are encoded by the VH4.21 or a very closely related VH4 heavy chain gene, whereas the expressed light chain genes differed. The anti-i-secreting B-cells express unmutated germline-encoded VH4.21 and VKI gene sequences. The VH region gene encoding anti-I has the closest homology (97%) to the VH4.21 germline gene and differs at the protein level by only three amino acids. In contrast, while the VL region gene encoding anti-I is most homologous (96%) to the VKIII, kv328 germline gene, there are seven amino acid differences due to nonrandom replacement mutations, which suggests a role for antigen-mediated selection in the anti-I response of this individual. These studies were extended by a structural survey of 20 additional serum CA using antipeptide antibodies specific for determinants in VH and VL regions. All anti-I and anti-i CA were shown to express VH4 heavy chains, and 14 of 17 CA expressed a previously described VH4 second hypervariable region determinant, termed VH4-HV2a. We also found that 13 of 14 anti-I CA used VKIII light chains, while the anti-i CA used light chains from at least three VL families. Taken together, the data show that anti-i and anti-I CA probably both derive from the VH4.21 gene (or a closely related gene). Furthermore, the restricted VH and different VL gene use in anti-i and anti-I CA may reflect the close structural relationship of the i and I antigens.

Autoantibodies↗
PubMed1991

Event-related potentials in depression: influence of task, stimulus hemifield and clinical features on P3 latency.

P3 latency, a brain event-related potential (ERP) correlate of stimulus evaluation time, was measured in 25 unmedicated depressed patients and 27 normal controls during auditory temporal and spatial discrimination tasks. Patients were divided into two subgroups, one having a typical major depression (melancholia or simple mood reactive depression) and one having an atypical depression. Typical depressives had abnormally long P3 latency for the spatial task but not the temporal task. They also showed an abnormal lateral asymmetry, with longer P3 latency for stimuli in the right hemifield than the left. In contrast, atypical depressives did not differ from normals in either respect. Longer P3 latency correlated with ratings of insomnia, while abnormal lateral asymmetry correlated with reduced right visual field advantage for syllables. The P3 latency findings point to a task-related slowing of perceptual decisions in a subgroup of depression.

Adjustment Disorders↗
PubMed1991

The effect of intravesical instillations of thiotepa, mitomycin C, and adriamycin on normal urothelium: an experimental study in rats.

The effects of intravesical instillations of thiotepa, mitomycin C and adriamycin on the normal urothelium were studied in rats. Changes in the bladder wall in the form of fibroblastic atypia and submucous fibrous plaques were significant in the mitomycin C treated group. In 46% of mitomycin C treated animals there was urothelial atypia and in one animal, the atypia was severe enough to resemble carcinoma in situ. None of the rats treated with thiotepa showed intramural fibrous plaques or fibroblastic atypia and only 8% showed urothelial atypia. In the group treated by adriamycin instillation, 17% showed intramural fibrous plaques, but none showed urothelial atypia or fibroblastic atypia. The fibroblastic atypia and submucosal fibrous plaques seen in the mitomycin treated group may explain the reduced bladder capacity seen in the clinical setting.

Administration, Intravesical↗
PubMed1991

Outcome of psychogenic seizures in children and adolescents compared with adults.

We compared outcome of psychogenic seizures documented by video-EEG in 18 nonepileptic children and adolescents (ages 8 to 18; median, 14.5 years old) and 20 adults (ages 25 to 56; median, 34.0 years old). Outcome was significantly better for the younger patients at 1 year, 2 years, and 3 years after diagnosis. At these follow-up times, the percentages of children and adolescents free of psychogenic attacks were 73%, 75%, and 81%; at the same follow-up times, the percentages of adults free of psychogenic attacks were only 25%, 25%, and 40%. Factors leading to better outcome for younger patients may have been different psychological mechanisms at different ages of onset and greater effectiveness with earlier intervention.

Adolescent↗
PubMed1991

Endometriosis of the terminal ileum simulating the clinical, roentgenographic, and surgical findings in Crohn's disease.

A 38-yr-old nulliparous female presented with endometriosis of the terminal ileum which mimicked the clinical, roentgenographic, and surgical findings of Crohn's disease. The patient presented with diarrhea, right lower quadrant pain, fever, and significant weight loss. At surgery, the terminal ileum was inflamed, indurated, thickened, and angulated. Ileal endometriosis may be expected to simulate Crohn's disease, because intestinal endometriosis frequently produces local bowel inflammation, adhesions, stricture, and angulation. Ileal endometriosis should be carefully considered in the differential diagnosis of Crohn's disease in menstruating females who are nulliparous and have dysmenorrhea, dyspareunia, dyschezia, menometrorrhagia, or other perimenstrual symptoms. It is important not to mistake endometriosis for Crohn's disease because endometriosis has a different therapy.

Adult↗
PubMed1991

Hepatic portal venous gas identified by computed tomography in a patient with blunt abdominal trauma: a case report.

An abdominal computed tomographic (CT) scan in a middle-aged man injured in a high-speed motor vehicle accident demonstrated the presence of portal venous gas. Findings on initial peritoneal lavage were entirely negative. Exploratory celiotomy performed because of increasing abdominal pain and leukocytosis revealed gangrene of the cecum. This report illustrates the importance of the finding of portal venous gas on CT scan in patients with blunt abdominal trauma.

Abdominal Injuries↗
PubMed1990

Endogenous event-related potentials in obsessive-compulsive disorder.

Brain event-related potentials (ERPs) were used to investigate central nervous system (CNS) correlates of cognitive function in obsessive-compulsive disorder (OCD). ERPs of 10 unmedicated OCD patients and 10 normal controls were measured in an auditory "oddball" task. Increasing task difficulty resulted in longer N200 and P300 latencies in normal subjects, but not in OCD patients. Moreover, OCD patients displayed shorter P300 latency than normal controls for the more difficult discrimination conditions. This replicates prior findings of Beech et al. (1983) for a visual task. For both levels of task difficulty, OCD patients also showed greater negativity than normal controls in the N200 region, which extended into the subsequent slow wave region. Negativities in the N200 and slow wave regions were larger at sites over the left hemisphere than the right hemisphere. The enhanced negativities and reduced P300 latency in OCD patients are discussed in terms of current theories postulating cortical hyperarousal and left hemisphere involvement in OCD.

Adolescent↗
PubMed1990

In situ hybridization analysis of human papillomavirus DNA segregation patterns in lesions of the female genital tract.

Various histologic features may be used to divide human papillomavirus (HPV)-related lesions of the genital tract into two groups: condylomata and "low-grade" or grade 1 cervical intraepithelial neoplasias (CIN 1) versus "high-grade" or grade 2 and 3 intraepithelial neoplasias. Using in situ hybridization analysis we correlated HPV DNA type with histologic features in 350 biopsies of lesions from the cervix, vulva, and perianal region. HPV DNA was most commonly found in vulvar and perianal condylomata (39/46, 85%), whereas the rate in CIN 1 lesions was 72% (86/120). The rates were 53% (40/76) and 57% (12/21) in CIN 2/3 and vulvar intraepithelial neoplasm (VIN) grades 2 and 3, respectively. The HPV type in all but 2 of the 39 perianal and vulvar condylomata which contained HPV was 6/11. Despite their similar histologic features, the HPV type in only 23 of 86 (27%) CIN 1 cases with detectable HPV was 6/11 compared to 31 of 86 (36%) which contained HPV 16-related DNA and 32 of 86 (37%) which contained HPV 31,-33, or -35-related DNA. The viral DNA in the majority of CIN 2/3 lesions and all of the VIN 2/3 lesions was HPV-16 related; no CIN 2/3 or VIN 2/3 lesion had HPV 6/11-related DNA. It is concluded that although cutaneous genital tract condylomata are highly associated with HPVs of low oncogenic potential (types 6 and 11), these HPV types are not as frequent as the oncogenic HPVs (16, 31, 33, and 35) in CIN 1 lesions. Further, HPV 6/11 appears to be very rarely associated with CIN 2/3 or VIN 2/3 lesions.

Condylomata Acuminata↗
PubMed1990

Longitudinal and cross-sectional comparisons of young children's cognitive ERPs and behavior in a picture-matching task: preliminary findings.

Event-related brain potentials (ERPs) were recorded from 19 children (6-8 years old at initial testing) performing cognitive tasks in two longitudinal testing sessions administered one year apart. The task used was a modification, using pictorial stimuli, of Posner's (1978) letter-matching experiments. In separate blocks of trials, subjects had to decide whether two sequentially-presented slides were physically identical, shared the same name, or came from the same semantic category. Subjects indicated their choice via a same-different delayed response following the second slide. Behavioral data showed large effects of longitudinal Age reflecting increases in accuracy from Run 1 to Run 2. These effects were corroborated by analyses of cross-sectional Age, suggesting that the performance changes reflected cognitive growth, rather than practice effects. In a similar fashion, both N400 and P700 (classical 'P300') showed reductions in peak latency that appeared to be true age changes, since these latencies shortened as a function of Run of testing as well as cross-sectional Age, and there were no Run by Age interactions. Small sample sizes as well as methodological shortcomings of the current design limit the conclusions that can be drawn from these data. Nevertheless, this study demonstrates the feasibility and usefulness of a cross-sectional/short-term longitudinal design and provides information on the extent and direction of behavioral and ERP changes that can be observed over this limited age range.

Child↗
PubMed1990

Cardiac deceleration and E-wave brain potential components in young, middle-aged and elderly adults.

Event-related potentials (ERPs), heart rate, and behavioral data were recorded from young, middle-aged, and elderly adults during an S1-S2 recognition memory paradigm. Anticipatory and evoked cardiac decelerations decreased significantly with age, as did the accuracy of recognition memory. The E-wave prior to S2 did not differ with age, however, and was not correlated with heart rate deceleration in any age group. Correlations between physiological measures and performance were weak in all groups. Taken together, the data provide little support for the hypothesis that the poorer recognition memory of older adults is related to an increasing uncoupling of E-wave and anticipatory heart rate with age.

Adult↗