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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Medulloblastoma and acute lymphocytic leukemia patients treated by intrathecal methotrexate and radiation were investigated by means of computerized axial tomography. More than 50% of them turned out to have acquired encephalopathy. Only gross morphologic brain defects, as visualized by computerized tomography, caused manifest clinical signs of brain dysfunction, such as epilepsy, mental retardation, paresis, and apallic syndrome. Mild morphologic changes were found even in asymptomatic children. The preferred site of defects in brain substance was the paraventricular white matter.
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PMID:Findings in computerized axial tomography after intrathecal methotrexate and radiation. 28 21

The purpose of this review has been to examine the hypothesis that the Attention Deficit Hyperactivity Disorder (ADHD), formerly also referred to as the Hyperactive Syndrome or Minimal Brain Dysfunction (MBD), is a precursor of criminality and abuse of alcohol and illicit drugs. This has been done by reviewing findings from follow-ups. Most reviewed projects suffer from methodological weakness. In most materials, few if any of the cases had ADHD according to present criteria. Some had ADHD and conduct problems. Many probably had exclusively conduct problems, but were too young to fulfill the criteria of Conduct Disorder (CD). Methodological limitations of the examined projects have been pointed out. It has been discussed how weaknesses regarding research design might have influenced the results. As a consequence of methodological shortcomings of most projects, the reviewed studies do not give definite answers. However, they show some rather convincing trends. By early adulthood, ADHD appears to remain present in at least one third of the subjects. Subjects with prior ADHD did not have more mental problems than controls in adolescence and early adulthood, provided they had normal intelligence, and no additional disabilities or mental disorders. Those with mental retardation, cerebral dysfunction or psychosis in addition to ADHD have a poor prognosis. A high percent become psychotic, and some end up in institutions. Although there seems to be an increased rate of delinquency and lawbreaking in prior hyperactives compared to controls, these differences disappear when the results are analyzed. The initially impressive differences between cases and controls are probably consequences of bias. Cases with a childhood history of conduct and educational problems have been compared to controls without a history of such problems. Thus, the reported differences are not related to ADHD. Hyperactives without conduct problems do not have an increased frequency of delinquency. Problems of conduct, CD and Antisocial Personality Disorder, but not psychosis characterize cases with a childhood history of conduct problems (with or without ADHD). In subjects with ADHD as well as conduct problems in childhood, conduct problems and not ADHD predict the prognosis, which is worse than for those with CD without ADHD. ADHD combined with delinquency indicates a high rate of subsequent lawbreaking. Usually, cases have more problems than controls with alcohol and illicit drugs, but this might be the consequence of selection of cases (subjects with school and conduct problems) and controls (subjects without such problems).(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Follow-ups of children with attention deficit hyperactivity disorder (ADHD). Review of literature. 164 37

The transport of the eight amino acids (phenylalanine, tyrosine, tryptophan, valine, leucine, isoleucine, histidine and methionine) using the large neutral amino acid transporter of the blood-brain barrier (BBB) has been calculated using published kinetic data. The fate of the amino acids has been followed from blood to interstitial space, to cell and through metabolism which included, for tyrosine and tryptophan, the hydroxylases. The system was analysed in terms of flux control coefficients. Since the summation theorem did not hold, the system clearly behaved as a non-homogeneous system. At physiological levels of these eight amino acids, the largest contribution to the control of the flux of tyrosine is given by the hydroxylase step, followed by the diffusional component of the transport across the BBB. For tryptophan it is the hydroxylase step, followed by the carrier-mediated transport across the BBB. For the other amino acids it is the metabolism, followed by the diffusional component of the BBB transport. These parameters for tyrosine and tryptophan were determined at increased levels of blood phenylalanine, tyrosine or histidine. The flux through tryptophan hydroxylase can be affected by high blood levels of tyrosine and histidine to values also observed in hyperphenylalaninaemia. Since hypertyrosinaemia (type II) and hyperhistidinaemia are not associated with mental retardation, it is concluded that interference with transport across the BBB of tyrosine and tryptophan, as well as the flux through tryptophan hydroxylase leading to the synthesis of 5-hydroxytryptamine, do not contribute to the cause of permanent brain dysfunction in hyperphenylalaninaemia. It can be calculated that addition of tyrosine to the diet to raise the blood tyrosine level in phenylketonuria patients may have a beneficial effect for the synthesis of neurotransmitters derived from tyrosine.
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PMID:The control of 5-hydroxytryptamine and dopamine synthesis in the brain: a theoretical approach. 210 47

Calculations on the rate of entry of the neutral amino acids into the brain via the blood-brain barrier show that a considerable decrease in this rate, particularly for tryptophan and tyrosine, takes place in histidinaemia and tyrosinaemia, type II. These conditions are, however, not associated with mental retardation. It is therefore concluded that effects at the blood-brain barrier alone do not provide an adequate explanation for the aetiology of permanent brain dysfunction in hyperphenylalaninaemia.
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PMID:The role of the blood-brain barrier in the aetiology of permanent brain dysfunction in hyperphenylalaninaemia. 250 82

The improved survival of extremely premature infants has generated intense interest in the quality of life of the survivors. This review focuses on the major long-term complications of prematurity (developmental disability, retinopathy of prematurity, chronic lung disease) and concludes with an overview of the broader spectrum of morbidity. Severe impairment (cerebral palsy, mental retardation, retrolental fibroplasia, severe chronic lung disease) fortunately occurs in a small proportion of survivors. However, the prevalence of the lesser morbidities (minimal cerebral dysfunction/learning disability, poor growth, postneonatal illnesses, rehospitalization) is less clearly defined. These problems all have an impact on families, and on medical and educational services.
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PMID:Medical complications of prematurity. 293 64

The conditions of childhood that follow prenatal or perinatal problems are defined. These conditions are mental retardation in varying degree, the cerebral palsies, the syndrome of minimal cerebral dysfunction, language disorders and defects of hearing and vision. The difficulties in accurately measuring disability and handicap are discussed and an estimate of the size of the problem is offered. The contribution made by the low birthweight group is also considered and it is pointed out that, although within this group there is a much higher incidence of problems, the majority of children with handicapping conditions were of normal birthweight.
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PMID:Antenatal and perinatal causes of handicap: definitions and size of the problem. 304 93

Long latency auditory event-related potentials have been shown to change in patients with cerebral dysfunction. Some seizure patients with no evidence of brain damage or mental retardation show altered interictal cognitive and memory function. Long-latency auditory event-related potentials to tone stimulation were recorded in nineteen control subjects and seventeen patients with complex partial or partial and secondarily generalized seizures who had no evidence of brain damage, retardation, or drug intoxication, and whose seizures were controlled when studied. The latencies of N2 and P3 components were significantly longer in seizure patients than control subjects, and the P3 waveform was significantly greater in amplitude in epileptics. These findings suggest that cognitive event-related potentials are affected by partial epilepsy. The changes may be related to the recently reported involvement of the hippocampus in ERP generation, or to loss or alteration of modulatory functions, possibly cholinergic in nature, in the temporal lobe consequent upon epileptogenesis.
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PMID:Long-latency auditory event-related potentials in epilepsy. 308 37

The total population of children under 10 years in one Swedish urban area and one rural area was screened for infantile autism (IA) and autistic-like conditions (AC). A total prevalence of 6.6 per 10 000 was found, which is somewhat higher than in previous similar studies of the same region. Infantile autism accounted for two-thirds of the cases. Boys far outnumbered girls, but this was entirely accounted for by the IA group. The preponderance of autistic boys was less pronounced among the severely mentally retarded children. Mental retardation was seen in almost 90% of cases and only one child had an IQ exceeding 100; clinical and laboratory signs of brain dysfunction were also found in a majority of cases. Distribution by social class was no different in either patient group from the general population.
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PMID:Autism and autistic-like conditions in Swedish rural and urban areas: a population study. 377 17

43 pre-term newborns with birth weight of less than 1,500 grams who had been admitted to the Neonatal Intensive Care Unit of the Department of Pediatrics of the University Clinic, Bonn, between 1971 and 1977, were reexamined on age between 1-7 years. A severe neurological handicap (hemiplegia with mental retardation) was present in only one child. There was no child with convulsions. Signs of minor cerebral dysfunction were present in five children. Developmental retardation of mild degree was observed in eight children. 28 children were entirely normal. Our results are in accordance with the encouraging reports of other recent authors concerning the improving long-term prognosis of very-low-birth-weight pre-term infants.
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PMID:[Follow-up pre-term newborns with birth weight of less than 1500 grams now aged between 1-7 years (author's transl)]. 611 1

Progress in the study of infantile autism over the past 10 years was reviewed in terms of classification and diagnosis, relation to other disorders, demographics, parental characteristics, genetics, intelligence, language, perceptual processes, behavioral characteristics, neurobiological, biochemical and pharmacological aspects, behavioral/educational treatment methodologies, prognosis, and theoretical considerations. This decade's research led to the now generally accepted position that infantile autism is a type of developmental disorder accompanied by severe and, to a large extent, permanent intellectual/behavioral deficits. However, its relationship to other forms of developmental disorders and to mental retardation remains to be delineated. Perceptual/cognitive/language defects appear central to the autistic syndrome, but the specific underlying mechanisms are unknown. Most studies indicate that autistic children have more signs of brain dysfunction than do normal children and about the same number as mentally retarded children. The overwhelming evidence suggests that te treatment of choice for maximal benefit to autistic children is a systematic, intrusive behavioral/educational approach. Yet, in spite of significant gains in almost all children treated, the typical prognostic picture is poor in terms of achieving self-supportive adulthood. The parents of autistic children have been found to be essentially similar to parents of children with organic brain disorders, and manifest no psychopathology which conceivably could induce the disorder. The vast majority of theoretical articles appearing in the 1970s proposed some from of neurobiological defect as the causative factor in autism. One of the major goals for future research is to undertake more extensive comparative studies on nonautistic brain dysfunctional children and autistic children that could yield cleared differential behavioral profiles and testable neurobiological hypotheses.
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PMID:Infantile autism reviewed: a decade of research. 611 76


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