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G Brieger

Publications and source records attributed to G Brieger.

7 recordsLinked to original sources
PubMed1993

Uptake and depuration of PCB 77, PCB 169, and hexachlorobenzene by zebra mussels (Dreissena polymorpha).

Zebra mussels (Dreissena polymorpha) were examined for their ability to take up and depurate hexachlorobenzene (HCB), 3,3',4,4'-tetrachlorobiphenyl (PCB 77), and 3,3',4,4',5,5'-hexachlorobiphenyl (PCB 169) in the laboratory. The intent was to investigate response to acute exposure at high contaminant levels and to observe the time course of depuration. Tissue loads of all three compounds taken up from food increased rapidly and peaked after 10 (PCB 169), 14 (PCB 77), and 21 (HCB) days followed by rapid depuration to equilibrium levels. Peak tissue loads were 3.7, 3.4, and 3.6 micrograms/g for PCB 169, PCB 77, and HCB, respectively (wet weight basis). Equilibrium levels were approximately 1.0 microgram/g for both PCB 169 and HCB. Uptake rate of PCB 77 followed the order: sediment > food > water. Dreissena sampled from five Great Lakes field sites had tissue Aroclor loads ranging from 120 to 530 ng/g for Aroclor 1242 and 33 to 270 ng/g for Aroclor 1254 (wet weight basis). PCB 77 was detected at 1.9 ng/g at one site. Tissue levels for both Aroclors in Dreissena were approximately 10 times those of Lampsilis siliquoidea, a unionid bivalve to which they were attached. Where Dreissena reaches high densities, it is likely to play a significant role in contaminant dynamics.

Animals↗
PubMed1987

Establishment of a collaborative university-commercial maternal serum alpha-fetoprotein screening program: a model for tertiary center outreach.

Expansion of the availability of tertiary level services beyond major medical centers has proved to be a major problem in health care delivery. Routine maternal serum alpha-fetoprotein screening for neural tube defects, and now also for aneuploidy, is a classic example in which there has been a schism between the clinical expertise to manage such a program within a tertiary level reproductive genetics center and the ability to reach patients in regions that are not routinely accessible to the tertiary center. To address this problem we have established a collaborative university-commercial laboratory statewide maternal serum alpha-fetoprotein program that we believe can serve as a model for others. In the first 4 months since its implementation, the program volume has increased tenfold. The detection frequency of neural tube defects has been consistent with that of other programs (1/1690). Three aneuploid karyotypes were found in amniotic fluid of 118 women less than 30 years old who underwent genetic amniocentesis because of a low maternal serum alpha-fetoprotein value. Thus we conclude that: the establishment of a joint university-commercial maternal serum alpha-fetoprotein program may provide a successful model for efficient tertiary center outreach, assessment of our data suggests that a population at high risk for abnormal fetuses can be identified among patients not generally considered at high risk, low maternal serum alpha-fetoprotein values may likely be a more important public health measure than high ones.

Adolescent↗