Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have compared constitutional and tumor genotypes in nine cases of hereditary Wilms tumor (WT) and in three unrelated cases of familial adrenocortical carcinoma (ADCC). Since susceptibility to these tumors can be observed in malformation syndromes associated with a constitutional deletion of band 11p13 (WT) and with a constitutional duplication of band 11p15.5 (WT, ADCC), we investigated these two candidate regions by using 11p polymorphic markers. As expected, somatic chromosomal events, resulting in a loss of heterozygosity limited to region 11p15.5, were observed in the tumor of two familial cases of adrenocortical carcinoma. Surprisingly, however, analysis of the WT of two patients with a constitutional deletion of band 11p13, associated with aniridia, genitourinary abnormalities, and mental retardation (WAGR syndrome), revealed a loss of heterozygosity limited to region 11p15.5. These data therefore suggest that observation of a specific loss of heterozygosity may not necessarily point to the site of the initial germinal mutation. Together with previous similar observations of a loss of heterozygosity limited to 11p15.5 in breast cancer and in rhabdomyosarcoma, our data suggest that region 11p15.5 may carry a non-tissue-specific gene that could be involved in genetic predisposition, in tumor progression, or in both.
 ...
PMID:Tumor-specific loss of 11p15.5 alleles in del11p13 Wilms tumor and in familial adrenocortical carcinoma. 256 68

Children with constitutional deletions of chromosome 11p13 suffer from aniridia, genitourinary malformations, and mental retardation and are predisposed to develop bilateral Wilms tumor (the WAGR syndrome). The critical region for these defects has been narrowed to a segment of band 11p13 between the catalase and the beta-follicle-stimulating hormone genes. In this report, we have cloned the endpoints from a WAGR patient whose large cytogenetic deletion, del(11)(p14.3::p13), does not include the catalase gene. The deletion was characterized using DNA polymorphisms and found to originate in the paternally derived chromosome 11. The distal endpoint was identified as a rearrangement of locus D11S21 in conventional Southern blots of the patient's genomic DNA, but was not detected in leukocyte DNA from either parent or in sperm DNA from the father. The proximal endpoint was isolated by cloning the junction fragment and was mapped in relation to other markers and breakpoints. It defines a new locus in 11p13-delta J, which is close to the Wilms tumor gene and the breakpoint cluster region (TCL2) of the frequent t(11;14)(p13;q11) translocation in acute T-cell leukemia. An unusual concentration of base pair substitutions was discovered at delta J, in which 9 of 44 restriction sites tested (greater than 20%) vary in the population. This property makes delta J one of the most polymorphic loci on chromosome 11 and may reflect an underlying instability that contributed to the original mutation. The breakpoint extends the genetic map of this region and provides a useful marker for linkage studies and the analysis of allelic segregation in tumor cells.
 ...
PMID:A highly polymorphic locus cloned from the breakpoint of a chromosome 11p13 deletion associated with the WAGR syndrome. 257 49

Results of radiation therapy for cerebellar medulloblastoma at Kyoto University Hospital were reviewed. Between 1962 and 1988, 30 patients with histologically-proven medulloblastoma completed radiotherapy. Before 1971, the treatment volume was either the posterior fossa only or posterior fossa plus spinal axis, but after 1972, it was extended to include the entire neuraxis. The mean dose was 48 Gy to the posterior fossa, 36 Gy to the whole brain, and 25 Gy to the spinal axis. The 5-year survival rate and 5-year relapse-free survival rate estimated by the Kaplan-Meier's method were 36% and 37%, respectively, for total cases, but were as high as 79% and 80%, respectively, for the recent 10 patients. This improvement in the treatment results appeared to be due to extensive tumor resection and improved radiotherapy technique, and not to the use of chemotherapy. The prognosis was significantly better in patients treated with craniospinal irradiation than in those otherwise treated. There was a trend towards better survival in patients who received 50 Gy or more to the posterior fossa or 24 Gy or more to the spinal axis, compared to the patients who received lower doses to each site. No significant morbidity of radiotherapy was seen. Four of the six surviving patients who were treated below age 12 have a mental retardation and/or a short stature, but one patient treated at age 5 has a normal growth and a good intelligence. From these analysis, it is recommended to irradiate craniospinal axis and posterior fossa up to 25-35 Gy and 50-55 Gy, respectively.
 ...
PMID:[Results of radiation therapy for medulloblastoma]. 261 86

After a brief introduction about the historic development of risk estimates and maximum permissible doses of ionizing radiation, the risks of prenatal irradiation are discussed. Experimental data mainly obtained with mice indicate that the most important risk exists during the period of organogenesis and concerns the induction of malformations. Although in man this period lies between about 10 and 80 days after fertilization for most organs, the main development of the brain occurs later, namely between the 8th and 15th week after conception. Data from Japanese victims of the atomic bomb explosions above Hiroshima and Nagasaki indicate that during development the brain is the most sensitive organ to irradiation and maximal sensitivity is found between the 8th and 15th week after fertilization. A dose of one Gray received during this period induces a severe mental retardation in about 45% of the newborns. The dose response relationship is not significantly different from a linear one without a threshold dose. Studies of intelligence and school performance have shown that 1 Gray received during the 8th-15th week causes a shift of the average intelligence of about 30 points. Irradiation before the 8th week and after the 25th week had no effect on intelligence or mental retardation. During the 16th and 25th week sensitivity was about one fourth of that during the 8th-15th week. Although the irradiation of the embryo and fetus should be avoided as much as possible, the new data have led to an abandonment of the so-called 10-day rule. Generally an accidental irradiation of the embryo or fetus of less than 5 cGy is not considered as a medical indication for abortion. Retrospective studies showed that mothers from children who died from leukemia or other childhood tumors, had been subjected to a diagnostic irradiation of the pelvis or lower abdomen more frequently than mothers from children that did not develop a tumor. It has been estimated that prenatal sensitivity for induction of leukemia and tumors is higher than sensitivity after birth. However, it is still in discussion, whether the relationship between prenatal irradiation and a higher incidence of tumors is of a causal nature.
 ...
PMID:Effects and consequences of prenatal irradiation. 269 43

Renal angiomyolipoma associated with tuberous sclerosis is well known. On the other hand, few cases of renal cell carcinoma in connection with tuberous sclerosis have been reported. We report a patient with tuberous sclerosis whose kidney was involved with renal cell carcinoma. A 18-year-old woman was first admitted in August 1987 for evaluation of left renal tumor. Diagnosis of tuberous sclerosis was made when she was 11 years old on the basis of mental retardation, papules on her face, seizures, white leaf-shaped macules and periventricular calcifications. Computerized tomographic scan demonstrated a large mass arising from the left kidney and small masses in the right kidney. Angiography confirmed bilateral hypervascular renal tumors. On these bases, a clinical diagnosis of bilateral renal angiomyolipomas was made and surgical treatment of the left kidney was recommended because of its large size. However, her parents did not permit treatment until March, 1988. Finally, left nephrectomy of 4,750 g was performed and histological examination revealed renal cell carcinoma with clusters of spindle cells. In the literature available to us, we found twelve reports of malignant renal tumors associated with tuberous sclerosis including five renal cell carcinomas in Japan.
 ...
PMID:[Renal cell carcinoma associated with tuberous sclerosis: a case report]. 269 34

The short arm of chromosome 11 carries genes involved in malformation syndromes, including the aniridia/genitourinary abnormalities/mental retardation (WAGR) syndrome and the Beckwith-Wiedemann syndrome, both of which are associated with an increased risk of childhood malignancy. Evidence comes from constitutional chromosomal aberrations and from losses of heterozygosity, limited to tumor cells, involving regions 11p13 and 11p15. In order to map the genes involved more precisely, we have fused a mouse cell line with cell lines from patients with constitutional deletions or translocations. Characterization of somatic cell hybrids with 11p-specific DNA markers has allowed us to subdivide the short arm into 11 subregions, 7 of which belong to band 11p13. We have thus defined the smallest region of overlap for the Wilms' tumor locus bracketed by the closest proximal and distal breakpoints in two of these hybrids. The region associated with the Beckwith-Wiedemann syndrome spans the region flanked by two 11p15.5 markers, HRAS1 and HBB. These hybrids also represent useful tools for mapping new markers to this region of the human genome.
 ...
PMID:Characterization of a panel of somatic cell hybrids for subregional mapping along 11p and within band 11p13. Subdivision of the WAGR complex region. 272 95

Seven school-aged children treated for temporal lobe astrocytomas with surgical resection and irradiation were prospectively tested to evaluate their intellectual, academic, personality, and neurologic status after therapy. At their most recent follow-up examination, neuropsychologic functioning was adequate in only two patients. The other five children manifested either intellectual deterioration, learning disability, mental retardation, or psychopathology. These deficits were associated with poor postoperative performance status, inadequate seizure control, tumor recurrence, and younger age at diagnosis. No pattern of intellectual, academic, or personality dysfunction emerged in association with left- versus right-hemisphere tumors.
 ...
PMID:Psychologic and neurologic function following treatment for childhood temporal lobe astrocytoma. 283 Mar 30

In a Nigerian town with a stable population of 20,000, a door-to-door survey was conducted, using a questionnaire involving a complete census and a simple neurological evaluation which had previously showed a 95% sensitivity and an 80% specificity for detecting neurological disease. Positive responders were evaluated and categorised, using agreed criteria for diagnoses. Nearly 100% cooperation was obtained. Life prevalence ratio for at least one episode of headache was 51/1000. Crude point prevalence ratio for migrainous headache was 5.3/100, and peak age-specific ratio was in the first decade. Prevalence ratio for epilepsy was 533/100,000 and peak age-specific prevalence ratio occurred in the 5-14 years age groups. The prevalence ratio for peripheral nerve disorders was 268/100,000, and age-specific prevalence ratio for tropical neuropathy increased with age. Prevalence ratio for stroke was rather low at 58/100,000, but was probably due to the people's attitude to the disabled elderly and high mortality of stroke which showed annual mortality rate of 70/100,000 which increased with age to 1519/100,000 per year in the eighth decade. Crude prevalence ratios (cases per 100,000) for others are 112 for neurological complications (including sciatica) of spondylosis, 15 each for poliomyelitis, motor neurone disease, development speech disorders, 10 each for syncope, hereditary neuropathies. Parkinson's disease, benign essential tremor, primary cerebellar degeneration, cerebral palsy, mental retardation, organic psychosis (probable intracranial tumor) and 5 each for muscular dystrophy, pyomyositis, spina bifida occulta, alcohol dependence and cerebral malaria. The implications of the findings are important for development of community neurological services in the developing countries.
 ...
PMID:Neurological disorders in Nigerian Africans: a community-based study. 303 73

We report a patient that fulfills the clinical features of the linear nevus sebaceous syndrome. This syndrome was defined by the triad: Linear nevus sebaceous, seizures and mental retardation. Further descriptions suggested an association with hamartomas of mesenchymal structures and increased risk of neoplasm transformation. Previously reported cases are reviewed. The complexity of classification of this neurocutaneous syndrome is discussed.
 ...
PMID:[Linear sebaceous nevus syndrome]. 332 Jun 21

In a group of 57 children with brain neoplasms with a long follow-up the authors assessed the neurological and somatic condition of these patients, as well as their mental development and social adaptation. It is suggested that a child completing successfully prolonged treatment (which includes in cases of malignant neoplasms also radiotherapy and chemotherapy) has a considerable likelihood of leading a relatively normal life. In most of these children the neurological deficit was absent or slight, and they could attend normal schools. The most frequent and most dangerous sequelae were vision disturbances (in about 12% of cases) due mainly to the site of the neoplasm. Attention is called also to growth disturbances as a result of radiotherapy. Another observed unfavourable consequence of radiotherapy is deterioration of intellectual abilities of the children, which was, however, usually at the level of slight mental retardation.
 ...
PMID:[Results of the treatment of children with brain neoplasms. II. Quality of life]. 344 99


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>