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Biomedical subjects

D Fein

Publications and source records attributed to D Fein.

At least 37 records · Page 2Linked to original sources
PubMed1996

Transforming growth factor beta 1 improves wound healing and random flap survival in normal and irradiated rats.

OBJECTIVES: To evaluate the effect of chronic irradiation on wound healing and random flap survival (FV), and the effect of transforming growth factor beta 1 (TGF-beta 1) in this setting using an animal model. DESIGN: A randomized, controlled study with four groups of rats to study the effect of irradiation 4 months before surgical intervention. The effect of TGF-beta 1 on FV and wound healing also was evaluated in the irradiated and nonirradiated groups. SUBJECTS: Ninety-five rats were available for evaluation. Group 1 (n = 10) was the control; group 2 (n = 28) received TGF-beta 1; group 3 (n = 28) received radiation therapy; and group 4 (n = 29) received radiation therapy and TGF-beta 1. INTERVENTION: The irradiated groups received 15 Gy to their dorsal skin. Four months later all received McFarlane skin flaps. Groups 2 and 4 received topical TGF-beta 1, 4 micrograms, to the bed of the flap; groups 1 and 3 received saline. On postoperative day 7 all rats were evaluated for tensile strength and FV, and histologic staining with hematoxylin-eosin for collagen and TGF-beta 1 was done. The slides were evaluated in a "blinded" fashion. RESULTS: Irradiation decreased tensile strength and FV, but not to a notable degree. Transforming growth factor beta 1 improved tensile strength in the irradiated (P = .04, Student's t test) and nonirradiated groups (P = .05, Student's t test). Transforming growth factor beta 1 also improved FV in all groups, but significantly in the irradiation plus TGF-beta 1 group (P = .001, Student's t test). The TGF-beta 1 group had the most mature collagen present at the wound edge. No qualitative difference was seen in the immunohistochemical staining for the four groups. CONCLUSIONS: Transforming growth factor beta 1 improves wound healing and random FV in radiated and nonirradiated rat skin. Further study is needed to determine the radiation dose necessary to create an "impaired wound-healing model" in rats, and the optimum dose of TGF-beta 1 in this setting.

Administration, Topical↗
PubMed1996

Diagnosis and classification in autism.

This study compared four systems for the diagnosis of autism (DSM-III, DSM-III-R, DSM-IV, and ICD-10) with two empirically derived taxa of autism, and with three social subgroups of autism (Aloof, Passive, and Active-but-Odd) in 194 preschool children with salient social impairment. There were significant behavior and IQ differences between autistic and other-PDD groups for all four diagnostic systems, and a significant association was found (a) for Taxon B, diagnoses of autism, and the Aloof subgroup, and (b) for Taxon A, other-PDD, and the Active-but-Odd subgroup. Findings offer support for two major overlapping continua within idiopathic Pervasive Developmental Disorder.

Algorithms↗
PubMed1996

Neurofunctional mechanisms in autism.

Behavioral impairments in autism are theorized to result from abnormal neuronal organization in brain development generating 4 systemically related neurofunctional impairments: (a) canalesthesia, wherein abnormal hippocampal system function "canalizes" sensory records, disrupting integration of information; (b) impaired assignment of the affective significance of stimuli, wherein abnormal amygdaloid system function disrupts affect association; (c) asociality, wherein impaired oxytocin system function flattens social bonding and affiliativeness; and (d) extended selective attention, wherein abnormal organization of temporal and parietal polysensory regions yields aberrant overprocessing of primary representations. This model proposes that complex human behaviors may be guided by multiple overlapping neural mechanisms.

Adolescent↗
PubMed1995

Social initiations by autistic children to adults and other children.

Social initiations made by autistic and verbal-matched retarded children were recorded in two naturalistic situations. Frequencies of initiation to adults did not differ between groups, but the retarded children initiated much more frequently to peers. Most interactions for both groups were positive, but the autistic children engaged in more ritualized, and the retarded children more playful, initiations. The autistic children monitored the social environment more when forced into proximity with peers, whereas the retarded children initiated more in the unstructured situation. Autistic initiation to peers was unrelated to severity of autism, but was related to cognitive skills, including vocabulary and comprehension of affect, whereas retarded children's initiations were unrelated to cognitive level. Results are discussed in terms of the differences between adults and children as social stimuli, prerequisite skills for initiation to peers, and the relationship between social cognition and social behavior. It is suggested that autistic and retarded children differ in the quantity of their initiations to peers, and the quality of their initiations to adults, and that initiations to peers may be a particularly useful index of social development in autistic children. Results confirm the need of autistic children for highly structured social environments, and suggest an important role for the remediation of specific cognitive skills such as comprehension of others' affects.

Adolescent↗
PubMed1992

Comprehension of affect in context in children with pervasive developmental disorders.

Fifteen children with Pervasive Developmental Disorders (PDD) (mean age 12.7 years) were compared to mental age matched normal children on matching a context to its appropriate emotion. PDD children were slightly but significantly impaired on this task relative to a non-social task equated for difficulty. Both matching tasks were highly correlated with cognitive variables; the social matching task alone was correlated with social skill level, and neither task was correlated with ratings of social deviance. Results are discussed in terms of the demands of social cognitive tasks, the magnitude of social cognitive findings, control group selection and individual differences.

Affect↗
PubMed1990

Sustained attention in children with autism.

Although many children with early infantile autism cannot maintain attention to externally imposed tasks, they may continue a repetitive behavior of their own choosing for long periods of time. This study examined the performance of autistic and mental age matched normal children on a Continuous Performance Test of sustained attention. Results suggest that autistic children's difficulties in sustaining attention on imposed tasks may be attributable partly to a developmental delay and partly to the motivational contingencies of task rather than to a primary impairment in the ability to sustain attention.

Adolescent↗
PubMed1989

Affect comprehension in children with pervasive developmental disorders.

Affect comprehension was studied in children with pervasive developmental disorders (PDD) and normal children matched for mental age. Three matching tasks were used: matching objects (a nonsocial control task), matching faces, and matching affects. The three tasks were developed to be of equal difficulty for normal children. Children were also tested for comprehension and expression of affect terms. The PDD children were impaired on affect matching relative to the normal controls. The PDD children were impaired on face and affect matching relative to their own performance on object matching, whereas the normal children were not. Within the PDD sample, object matching was correlated with mental age measures but not with measures of social behavior and play, but face and affect matching were significantly correlated with mental age as well as social behavior and play. Individual PDD children who showed relative deficits on face or affect matching tended to be more socially impaired than PDD children whose face and affect matching was consonant with their mental age. Results are discussed in terms of possible etiologies of the social deficit in PDD children, and the importance of subtypes within this population.

Adolescent↗
PubMed1987

Systematic misidentification of toes in normal adults.

This note reports a previously unreported phenomenon: when subjects are asked to indicate subjective correspondence between fingers and toes, there is a remarkably systematic miscorrespondence, consistent across subjects. No satisfactory explanation for these findings has been found.

Adult↗
PubMed1985

Handedness and cognitive functions in pervasive developmental disorders.

This paper is concerned with what abnormal handedness in Pervasive Developmental Disorders (PDD) reveals about the presence, lateralization, and severity of cerebral dysfunction in this population. From previous work, it was predicted that left-handedness would be elevated in the sample and that mixed-handedness subjects should be more impaired than those with established hand dominance. A battery of cognitive and motor tests were administered to a group of PDD children with autistic symptoms, and performance was compared for the left-handed, right-handed, and mixed-preference children. It was found that left-handers tended to do better than right-handers on all cognitive measures, while the mixed-preference children tended to be the lowest on all cognitive measures. No differences were found on motor measures. An extension of the Satz (1972) model, assuming early brain damage, was developed to explain the superiority of the left-handed children; an alternative explanation assuming anomalous lateralization patterns in the natural left-handers was also suggested.

Adolescent↗
PubMed1985

Cognitive subtypes in developmentally disabled children: a pilot study.

Differential diagnoses within the pervasive developmental disorders have insufficient reliability, validity, and descriptive homogeneity within groups to be used as distinct categories for research purposes. This study reports the results of cognitive subtyping of 54 developmentally disabled children. Fifty-one were successfully categorized in a small number of groups, characterized by different strengths and weaknesses on verbal, performance, memory, and quantitative tests. About half of the children had the relatively good visuospatial performance expected on the basis of previous literature on autistic children; these children were not behaviorally more autistic than the others. Measures of internal validity are reported, as well as validation by cognitive and behavioral variables. These results tentatively suggest that such psychiatric manifestations as autistic aloofness and maintenance of sameness may be relatively independent of cognitive skill patterns.

Adolescent↗
PubMed1984

Developmental trends in cognitive skills for children diagnosed as autistic and schizophrenic.

102 children whose histories included a diagnosis of infantile autism or childhood schizophrenia were followed longitudinally to assess cognitive developmental trends. Despite some sample attrition, administration of a test battery of 5 language skill measures and 2 perception skill measures during 5 test periods over 4 years yielded 336 usable test batteries. After all tests had been administered, diagnosis of subjects for autism and schizophrenia using developmental histories and behavioral observations drawn at the time of first test-battery administration showed 111 test batteries on 33 children diagnosed as autistic, and 100 test batteries on 27 children diagnosed as schizophrenic. Comparisons of age and test score correlations, comparisons of cross-sequential means, and trends for means for diagnostic subgroups and normal controls suggest developmental delay for all skills at all ages for both autistic and schizophrenic children. Findings also suggest a trend for steady prepubertal cognitive skill development, followed by a postpubertal decline in skills for both diagnostic groups.

Adolescent↗
PubMed1981

Clinical correlates of brainstem dysfunction in autistic children.

Children with the diagnosis of autism were tested for brainstem auditory evoked potentials (BAEP), and information was gathered on their medical and developmental histories and current developmental levels of symptomatology. On comparing the nine autistic children having abnormal BAEPs and the seven autistic children with normal BAEPs, the former were found to have exhibited greater pathology in the areas of attention and social accessibility. No differences were found between the groups on measures of language, motor, or perceptual functioning, or on previous diagnoses or medical history. It is suggested that social attentional pathology may be more specifically associated with the brainstem pathology that may characterize autism than are symptoms in other developmental areas.

Adolescent↗