Congenital defect

Arrhythmias. The first solution to cardiovascular problems arising from arrhythmias came about as a result of a complication caused by open-heart surgery. During procedures to correct congenital defects in children s hearts, the electrical conduction system often became impaired, and until it healed, the heart could not contract sufficiently without outside electrical stimulation. A system that plugged into a wall outlet was considered adequate until an electrical storm knocked out power, lea ding to the development of the first battery-powered external pacemaker. 

However, several situations can be anticipated in which support of the immune system is required. These include congenital defects in the immune repertoire, acquired immune deficiencies such as in HIV infection, but also situations in which the immune system is compromised after treatment of patients, e.g., after radiation or chemotherapy. 

A study of three Michigan communities exposed to chlorinated solvents including trichloroethylene (up to 14,890 ppb) in contaminated drinking water found no increase in congenital defects (Freni and Bloomer 1988). The size of the cohort, however, was smaller than that of other studies, making statistically significant associations more difficult to identify. 

Methyldopa Preferred first-line therapy on the basis of long-term follow-up studies supporting safety after exposure in utero. Surveillance data do not support an association between drug and congenital defects when the mother took the drug early in the first trimester. 

There are data on the jump in infant mortality in the pesticide-saturated cotton growing regions of Central Asia [1]. Central Asia and Moldavia had the largest number of newborns with congenital defects in the former USSR these were regions with the largest pesticide use per capita. 

Congenital defects in the metabolism of y-aminobutyric acid have been described 681... 

Congenital defects in the metabolism of y-aminobutyric acid have been described. GABA is formed via the action of glutamate decarboxylase (see Ch. 16). Metabolism of this neurotransmitter is mediated first by uptake into... 

Chashschin, V.P., G.P. Artunina, and T. Norseth. 1994. Congenital defects, abortion and other health effects in nickel refinery workers. Sci. Total Environ. 148 287-291. 

Hypothyroidism commonly occurs months to years after RAI. The acute, short-term side effects include mild thyroidal tenderness and dysphagia. Long-term follow-up has not revealed an increased risk for development of thyroid carcinoma, leukemia, or congenital defects. 

Infections are the result of hematogenous spread from a primary infection site, seeding from a parameningeal focus, reactivation from a latent site, trauma, or congenital defects in the CNS. 

Turner s Syndrome Instead of the XX female sex chromosome, female sufferers have only one X chromosome. Most fetuses do not survive. Those born are infertile and carry congenital defects in heart, kidney, and thyroid. 

Sullivan FM, Barlow SM. 1985. The relevance for man of animal data on reproductive toxicity of industrial chemicals. Prevention of Physical and Mental Congenital Defects, Part B Epidemiology, Early Detection and Therapy, and Environmental Factors. Alan R. Liss, Inc. 

McFarling also failed to find any evidence of chromosome damage or congenital defects. There were no cases of leukemia a commonly used indicator of toxicity. Subjects who claimed LSD-related infirmities listed a great... 

Congenital defects in the biosynthesis of steroid hormones can lead to severe developmental disturbances, in the adrenogenital syndrome (AGS), which is relatively common, there is usually a defect in 21-hydroxylase, which is needed for synthesis of cortisol and aldosterone from progesterone. Reduced synthesis of this hormone leads to increased formation of testosterone, resulting in masculin-ization of female fetuses. With early diagnosis, this condition can be avoided by providing the mother with hormone treatment before birth. 

An epidemiological investigation of New Zealand chemical applicators using 2,4,5-T found no significant differences in the rate of congenital defects, stillbirths, or miscarriages compared with controls. ... 

In 1976, a final report from the International Register of Lithium Babies contained information on 225 infants exposed to lithium in the first trimester. Cardiovascular anomalies occurred in 18 (8%) of the newborns, of which 6 (2.7%) had Ebstein s anomaly (Weinstein, 1976). A comprehensive review of this report and the multiple studies that have been conducted since (Cohen et ah, 1994) revealed that the risk of congenital defects after in utero exposure to lithium is less than previously anticipated. Currently, the risk for Ebstein s anomaly after first-trimester exposure to lithium is estimated to be 1 in 1000 (0.1%) (Altshuler et ah, 1996), or 10-20 times greater than the general population risk of 1 in 20,000 (Weinstein, 1976). Thus, the absolute risk for Ebstein s anomaly is small. 

TThe importance of the oligosaccharide moiety of these hormones is apparent from studies of individuals with a defective enzyme in the pathway that produces this oligosaccharide. Females with this congenital defect often fail to undergo the sexual changes of puberty (although males with the same defect develop normally). ... 

Relationship between Fructose 1,6-Bisphosphatase and Blood Lactate Levels A congenital defect in the liver enzyme fructose 1,6-bisphosphatase results in abnormally high levels of lactate in the blood plasma. Explain. 

The literature on epidemiologic findings is surveyed in other chapters of this book and elsewhere ( 5-7). As a summary, studies on food poisoning episodes have shown that the ingestion of alkylmercury and food oil contaminated by technical polychlorinated biphenyls leads to congenital defects in the offspring. It also appears to be relatively well proven that... 

Nguyen Can et al. (ref. 127c) found significantly higher rates of miscarriage, molar pregnancy and congenital defects in children whose fathers had served in South Vietnam when compared with those whose fathers had not. 

T4. Thelander, H. E., and Imagawa, R., Amino-aciduria, congenital defects, and mental retardation. A preliminary report. J.Pediat. 49, 123-128 (1956). 

---