Mental impairment retardation

Fragile X syndrome is the leading inherited cause of mental retardation in humans. It affects about 1 out of 2000 males and about 1 out of 4000 females. The degree of mental retardation is quite variable, from a mild mental impairment to severe mental retardation. The disease is frequently more serious in males than females males have only the defective X chromosome, whereas females have one normal X chromosome to go along with the defective one. There is no specific treatment for Fragile X syndrome. 

Folic acid deficiency can cause mental retardation in babies. That s a fact. So researchers at the University of Kentucky wondered whether a deficiency later in life could be associated with the mental impairment that sometimes characterizes aging. They elected to study a group of elderly Minnesota nuns who were keen on contributing to the advancement of science. Nuns are good subjects for studies on aging, because they tend... 

The physical and behavioral features of the disease in female patients are usually milder than in affected males. Somatic features may be absent or mild, although the faces of mentally retarded females tend to resemble those of male patients with advancing age. The intelligence deficit of female patients is less severe, with most patients having mild-to-borderline mental impairment. There is evidence of an increase in psychological and psychiatric problems among female patients. 

Male fetuses with 50 to 230 copies of the repeat should be asymptomatic, whereas those with more than 230 copies will have fragile X syndrome. Female fetuses with 50 to 230 copies also will be asymptomatic however, it is difficult to predict the extent of mental retardation in female fetuses with more than 230 copies of the repeat. Although hypermethylation of the CpG island is a poor prognostic indicator, it is not always present in DNA extracted from chorionic villus samples (Sutherland et al., 1991). Empiric data showing that female carriers with full mutations have nearly a 50% risk of mental impairment should be considered reliable. 

Current opinion comes from the intellectual functioning observed in case reports or large groups of children with varying levels of exposure measured with blood or dentine lead levels. Several reports link mental retardation or autism to higher blood lead levels, but few can determine whether higher lead levels cause the impairment or result from increased pica often observed in mentally impaired children. 

Children and adolescents goiter, impaired mental function, retarded physical development. 

This provision is included in the definition in part to protect individuals who have recovered from a physical or mental impairment which previously limited them in a major life activity. Discrimination on the basis of such a past impairment would be prohibited under this legislation. Frequently occurring examples of the first group (i.e., those who have a history of an impairment) are people with histories of mental or emotional illness, heart disease or cancer examples of the second group (i.e., those who have been misclassified as having an impairment) are people who have been mis-classified as mentally retarded. ... 

The earliest of these was that of Moncrieff et al. (1964) which is noteworthy for taking 36/tg Pb/lOOml blood as the upper limit of normal. This level has only become accepted in recent years, having been regarded as too low by earlier authors (e.g. Chisholm, 1965). Moncrieff found raised blood levels in 55% of 122 mentally retarded children but believed that the high lead levels were secondary, inasmuch as retarded children may have marked pica, and are more likely to ingest more lead than normal children. This extra lead ingestion might of course produce further mental impairment (Moncrieff et al., 1967). 

Zinc is essential for life. It is a component in many enTymes, which take an active part in metabolism, and it is of great importance for repHcation of the genetic codes of DNA and RNA [33.6]. Lead and cadmium are toxic partly because they take over the position of zinc in important enzyme molecules, which are thus made inactive. In the pancreas, zinc contributes to the preparation of insulin. Zinc deficiency leads to impaired wound healing and loss of hair. In addition, for children, a zinc deficiency may cause delayed mental developmenL retarded growth and postponed puberty. 

Juvenile hypothyroidism Impaired mental function Retarded physical development... 

CMV, a virus of the herpes family, isa common viral infection. Healthy individuals may beoome infected yet have no symptoms. However, immunocompromised patients (such as those with HIV or cancer) may have the infection. Symptoms include malaise, fever, pneumonia, and super infection. Infants may acquire the virus from the mother while in the uterus, resulting in learning disabilities and mental retardation. CM V can infect the eye, causing retinitis. Symptoms of CMV retinitis are blurred vision and decreased visual acuity. Visual impairment is irreversible and can lead to blindness if untreated. 

The answer is c. (Hardman, p 15.33.) Enthusiastic over medication with vitamin D may lead to a toxic syndrome called hy/jervitamijmsis D. The initial symptoms can include weakness, nausea, weight loss, anemia, and mild acidosis. As the excessive doses are continued, signs of nephrotoxicity are manifested, such as polyuria, polydipsia, azotemia, and eventually nephrocalcinosis. In adults, osteoporosis can occur. Also, there is CNS impairment, which can result in mental retardation and convulsions. 

Definitions of mental illness tend to contain two aspects a normative element and a functional element. Normative definitions delimit abnormal behavior in light of what is typical, usual, or the norm. Some degree of deviance from the norm is necessary for a behavior to be considered abnormal. Deviance alone, however, is never sufficient for a label of abnormality. High IQ is just as deviant as low IQ, but only mental retardation is labeled abnormal. This leads us to the functional element of the definition. Typically, the label of abnormality requires deviance plus maladaptation. Maladaptation suggests some diminished capacity to function relative to an average. For example, the DSM defines mental disorder as a syndrome that is associated with distress or impairment in functioning (American Psychiatric Association, 1994, pp- xxi-xxii). 

Mental Retardation Refers to sub-average general intellectual functioning which originated during the developmental period and is associated with impairment in adaptive behavior. 

A deficiency of iodine results iu insufficient synthesis of thyroxine and a low plasma level, so that secretion of TSH is increased in an attempt to stimulate synthesis but this results in enlargement of the thyroid gland (goitre). Iodine deficiency in pregnancy impairs brain development in the foetus, causing mental retardation (known as cretinism). Indeed iodine deficiency is one of the major public health issues worldwide an estimated 200 million people are affected. 

This chapter is concerned with the neurochemical basis of developmental disability which is considered here in two forms the globally delayed or halted development seen in mental retardation, and the more circumscribed pattern of disordered development of autism. A range of deficits of important key aspects of consciousness are apparent in both conditions. Of particular relevance to consciousness are the cognitive and behavioural impairments in attention, concentration, memory, information processing and social behaviour which are commonly present. Consideration of aberrant neurotransmitter activities in these developmental deficits may provide insights into the role of neurotransmitters in consciousness. 

This diversity of mental retardation, in both cause and phenotype, carries important implications for consideration of the biochemistry of consciousness. On the one hand, because this is an investigation of multiple causalities—including, for example, inborn errors of metabolism, each of which has its own unique biochemical profile (Cook Leventhal, 1996), it may not prove possible to identify specific neurotransmitter abnormalities which are common to mental retardation as such. On the other hand common themes concerning key neurotransmitters may be identified from studies of mental retardation. Altered neurotransmitter functioning associated with the severity of mental retardation is open to different interpretations, either reflecting fundamentally impaired development of cerebral structure or a more general impairment of central transmitter activity and functioning. 

Children with a range of developmental disorders appear to be at increased risk for tic disorders. Kurlan and colleagues (1994) reported a fourfold increase in the prevalence of tic disorders among children in special educational settings in a single school district in upstate New York. These children were not mentally retarded but did have significant learning disabilities or other physical impairments. 

Lamotrigine is an anticonvulsant drug that attenuates some forms of cortical glutamate release via inhibition of sodium, calcium, and potassium channels. An open-label case series (Uvebrant and Bauziene, 1994) and a case report (Davanzo and King, 1996) described improvement in autistic symptoms and self-injurious behavior, irritability, disturbed sleep, and social impairment in autistic children and an 18-year-old female with profound mental retardation, respectively, who were treated for epilepsy. 

---