Reversion of mutant strains of Salmonella Typhimurium by raw and finished waters from southeastern Louisiana

Samples of raw and finished water were collected from water treatment plants in southeastern Louisiana between January 1975 and May 1976. The water source for each plant is the Mississippi River. Finished water samples also were obtained at water treatment plants at St. Francisville, LA. and Baton rouge, LA. where deep wells serve as sources of water. All samples were assayed for mutagens using histidine dependent mutant strains of Salmonella typhimurium. Almost twice as many of the finished water samples collected at Luling, Jefferson and New Orleans induced reversions than did the corresponding raw water samples. Often reversion of finished water samples occurred only with metabolic activation. When samples from Belle Chasse and Port Sulphur were assayed, the number of finished water samples inducing reversion were comparable or less than comparable to those with raw water. Nearly equal numbers of finished water samples from St. Francisville and from Baton Rouge induced genetic change. However, the majority of the samples from Baton Rouge which caused reversion, did so only with liver enzyme activation. Discussed is the significance of these findings, as well as the possible role of chlorination procedures in halogenating hydrocarbons into compounds which are mutagenic and/or carcinogenic.     

Some Advances in Fluorometric Techniques for Water Tracing

A common technique for ground water tracing uses continuous or discrete analysis of fluorescent tracer dyes to produce tracer breakthrough curves which can be analysed to determine ground water trajectory, velocity and dispersivity. Some fluorescent dyes are excellent tracers, but there remain significant constraints in fluorometry with respect to installation, control and data acquisition using standard filter fluorometers as well as with general analytical protocols. This paper identifies some of the constraints associated with the widely used Turner Designs Model 10 Series filter fluorometer and technical and operational solutions which can significantly improve the precision, accuracy and time resolution of tracer data.     

Etiology and management of early pregnancy renal anhydramnios: Is there a place for serial amnioinfusions?

Early pregnancy renal anhydramios (EPRA) comprises congenital renal disease that results in fetal anhydramnios by 22 weeks of gestation. It occurs in over 1 in 2000 pregnancies and affects 1500 families in the US annually. EPRA was historically considered universally fatal due to associated pulmonary hypoplasia and neonatal respiratory failure. There are several etiologies of fetal renal failure that result in EPRA including bilateral renal agenesis, cystic kidney disease, and lower urinary tract obstruction. Appropriate sonographic evaluation is required to arrive at the appropriate urogenital diagnosis and to identify additional anomalies that allude to a specific genetic diagnosis. Genetic evaluation variably includes karyotype, microarray, targeted gene testing, panels, or whole exome sequencing depending on presentation. Patients receiving a fetal diagnosis of EPRA should be offered management options of pregnancy termination or perinatal palliative care, with the option of serial amnioinfusion therapy offered on a research basis. Preliminary data from case reports demonstrate an association between serial amnioinfusion therapy and short-term postnatal survival of EPRA, with excellent respiratory function in the neonatal period. A multicenter trial, the renal anhydramnios fetal therapy (RAFT) trial, is underway. We sought to review the initial diagnosis ultrasound findings, genetic etiologies, and current management options for EPRA.