Congenital Anorectal Malformation Embryonic Development, Gene Expression And Long-term Quality Of Life Of The Study

Anorectal malformation (ARM) is the most common disorder affecting I/ 5000 to 1/1500 live births, one kind of malformations supervised by World Heahh Organization. ARM severely influences quality of life, and put great burdens on families and society.The genetic, embryological, and pathogenic aspects of ARM are poorly understood and controversial. It has been only demonstrated that ARM resulted from impeded rectal development during embryonic stage. Developmental principles of normal anorectum remain poorly understood, much less the pathogenesis of ARM.Genetic and environmental factors interact on each other to give rise to ARM. Epidemiological and animal experiments led to the conclusion that genetics played an important role in the occurrence of ARM. But the spectrum of ARM is fairly wide, pathogenesis and pathological changes are complex. ARM is also often associated with extraanal anomalies, and its phenotypes are rather variable, so it is very difficult to perform gene investigation. The pathogenic genes are still unlocated, even the candidate gene remains unknown. Therefore, it is significant to investigate pathogenesis of ARM on embryonic and molecular level.In the current study, contents are as follows: â‘ Embryonic development: Rat embryos with ARM were obtained by treating with administration of ethyle-nethiourea (ETU) on pregnant rats. We explored the development of ARM by continuous and dynamic observation of anorectal morphogenesis in the involved embryos from gestational days 12. 5 to 20. â‘¡Gene expression; RT - PCR and cDNA microarrays were used to detect developmental genes expression of ARM and normal terminal rectum, explore relativity of ARM to these genes and investigate pathogenic genes. â‘¢ Quality of life; Eight patients after surgically corrected ARM were followed up for 33 to 41 years. The quality of life was assessed by using an interview and a modified Quality of Life Questionnaire.MaterialsAnimals; Wistar rats were provided by Medical Animal Center, the Second Clinical College of China Medical University.Samples; Among 19 congenital. ARM infants operated in our department, 10 were males, and 9 were females., aged from 2 days to 3 years. Tissues were removed from terminal pouch of rectum and stored immediately in fluid nitrogen. In the control group, tissues were obtained at point 1 cm to dentate line in acquired anal fistula and rectal trauma infants.Reagent; â‘ TUNEL kit was provided by Boster Biological Technology Co. , Ltd. Wuhan. â‘¡Bca BEST RNA PCR kit verl. 1 ( AMV) was provided by Taka-ra Biotechnology Co. , Ltd. Dalian.â‘¢Gene chips were provided by BioStar Ge-nechip Inc. , Shanghai. Type: GCs.MethodsEmbryonic development; Cloaca malformation and ARM rats were produced by treating with administration of ETU on pregnant rats. Normal rat embryos and embryos with ARM from gestational days 12. 5 to 20 were sectioned serially and sagittally and stained with HE to observe development of cloaca and anorectum continually and contrastively. Some slices were stained with TUNEL to identify the distribution of apoptotic cells.Gene expression; RT -PCR was used to investigate Hoxdl3 gene expression in rectal terminus of 16 infants with ARM and 5 normal infants, and cDNA microarrays to investigate mRNA in that of 3 infants with ARM and normal infants.Quality of life; Eight patients (aged 33 to 41 years old) after surgically corrected ARM were followed up for 33 to 41, years. The quality of life was assessed by using an interview and a modified Quality of Life Questionnaire for the adult patients after surgically corrected ARM including ten items in six areas ofeveryday life ( bowel function, food, occupational life, social activity, sexual life, and psychological aspects ). Twenty - four healthy people with similar age, sex and education level distributions served as controls.ResultsEmbryonic development; During normal cloaca development process in rats, before gestational days 15, the urorectal septum (URS) developed and clearly demarcated th...