An epidemiological study of the factors influencing poisoning in children aged 0-5 years.

The aim of this cross disciplinary study was to identify the most significant variables related to childhood accidental poisoning. The study was carried out on a representative sample of families living in the Greater Athens Area comprising 1245 children aged up to 5 years. Data were collected by a team of researchers (paediatricians, psychologists and social workers) and involved a structured interview and a paediatric examination. The findings show that childhood poisoning is correlated with: (1) biological variables, such as skeletal anomalies, language disorders, number of recent infections and complications of pregnancy; and (2) social factors, such as father's educational level, monthly family income, and overcrowding. Sex of the child was not found to influence poisoning.

The cytogenetic and clinical implications of a ring chromosome 2.

Ring chromosome formation can occur without deletion, through the abnormal pairing of the palindromic DNA base sequences thought to make up the telomeres. The normal occurrence of sister chromatid exchanges within a ring constantly produces further chromosomal anomalies that are less likely to survive when the chromosome involved is large and/or its aneuploidy incompatible with life. These abnormal products (abbreviated pro) were only found in the present case after two or more cell cycles in lymphocyte cultures. Their elimination in vivo implies a very high cellular death rate and an enormous waste of metabolism that should have the same phenotypic effects no matter what chromosome is involved. These phenotypic anomalies form a ring syndrome that can be clinically recognized and consists of severe growth failure, mental retardation and a pleasant personality. The syndrome is usually masked by the more severe abnormalities produced by the deletions present in most cases of ring chromosomes.