High resolution chromosomes from first trimester trophoblast cultures

A simple method for obtaining prometaphase chromosomes from cultured first trimester cells involves the addition of BrdU and FdU 11 h before harvest and ethidium bromide 1.5 h before harvest. High resolution R-banding is obtained by acridine orange staining.     

Transabdominal chorionic villi sampling for first trimester fetal diagnosis. First 26 pregnancies followed to term

A consecutive series of 26 women followed to term after first trimester transabdominal chorionic villi sampling is presented. The clinical application of transabdominal chorionic villi sampling (TA-CVS) seems to have certain advantages, especially from the patients' point of view, but also in regard to successful sampling and to the complication ratio. The results in this clinical trial revealed no cases of abortions, no signs of placental damage and no cases of vaginal bleeding or infections.     

Disaccharidase deficiency in amniotic fluid from cases of cystic fibrosis

The activities of the disaccharidases maltase and sucrase in 4 amniotic fluid from cystic fibrosis (CF) pregnancies have been compared to those of 120 non CF-pregnancies. Very low levels were found in 3 of the CF-fluids. The fourth CF-fluid was normal in all measured microvillar enzyme activities. Elevated levels of disaccharidases in meconium from one of the patients born with CF, supports the idea that these enzymes are trapped in the intestinal cavity by sticky meconium.     

Linking abundance and diversity of sponge-associated microbial communities to metabolic differences in host sponges

Many sponge species contain large and diverse communities of microorganisms. Some of these microbes are suggested to be in a mutualistic interaction with their host sponges, but there is little evidence to support these hypotheses. Stable nitrogen isotope ratios of sponges in the Key Largo, Florida (USA) area grouped sponges into species with relatively low δ¹⁵N ratios and species with relatively high δ¹⁵N ratios. Using samples collected in June 2002 from Three Sisters Reef and Conch Reef in the Key Largo, Florida area, transmission electron microscopy (TEM) and denaturing gradient gel electrophoresis were performed on tissues of the sponges Ircinia felix and Aplysina cauliformis, which are in the low δ¹⁵N group, and on tissue of the sponge Niphates erecta, which is in the high δ¹⁵N group. Results showed that I. felix and A. cauliformis have large and diverse microbial communities, while N. erecta has a low biomass of one bacterial strain. As the low δ¹⁵N ratios indicated a microbial input of nitrogen, these results suggested that I. felix and A. cauliformis were receiving nitrogen from their associated microbial community, while N. erecta was obtaining nitrogen solely from external sources. Sequence analysis of the microbial communities showed a diversity of metabolic capabilities among the microbes of the low δ¹⁵N group, which are lacking in the high δ¹⁵N group, further supporting metabolic differences between the two groups. This research provides support for hypotheses of mutualisms between sponges and their associated microbial communities.     

Transabdominal chorionic villus sampling for fetal genetic diagnosis. Technical and obstetrical evaluation of 100 cases

First trimester fetal diagnosis was established in 100 pregnancies at risk by transabdominal chorionic villus sampling (TA-CVS). Forty-eight per cent of the women were 35 years or more at the time of sampling. Using the double needle technique, both the aspiration and the diagnostic success rate were 100 per cent. The mean amount of villi aspirated was 28·2 mg (10–50 mg). The mean needle time was 3 min. Vaginal spotting appeared in 2 per cent of the women. Four women had therapeutic abortion due to abnormal findings and one for social reasons. Three fetuses with normal karyotypes were lost. Excluding the therapeutic abortions, the fetal loss rate was 3±2 per cent. The fetal loss rate in the amniocentesis control group (n = 200) was 3±6 per cent. The cytogenetic diagnosis was carried out by the direct preparation technique as well as by chorion villus cultivation. All karyotypes were confirmed by lymphocyte cultures from umbilical cord blood or heel blood from the newborn or from aborted fetal tissue. Transabdominal CVS is deemed a safe and easy tool for achieving chorionic villi in the first trimester.     

Integrating data-driven ecological models in an expert-based decision support system for water management in the Du river basin (Vietnam)

In this study, classification trees were combined with the Water Framework Directive (WFD)-Explorer, a modular toolbox that supports integrated water management in a river basin to evaluate the impact of different restoration measures on river ecology. First, the WFD-Explorer toolbox analysed the effect of different restoration options on the abiotic river characteristics based on the water and substance balance embedded in the simulation environment. Based on these abiotic characteristics, the biological index Biological Monitoring Working Party for Vietnam was then predicted by classification trees that were trained on biological and abiotic data collected in the Du river basin in northern Vietnam. The ecological status of streams in the basin ranged from nearly pristine headwaters to severely impacted river stretches. Elimination of point sources from ore extraction and decentralised domestic wastewater treatment proved to be the most effective measures to improve the ecological condition of the Du river basin. The combination of the WFD-Explorer results with data-driven models enabled model application in a situation where expert knowledge was lacking. Consequently, this approach appeared promising for decision support in the context of river restoration and conservation management.     

From mother to child: investigation of prenatal and postnatal exposure to persistent bioaccumulating toxicants using breast milk and placenta biomonitoring

The exposure levels of placenta and paired breast milk samples to selected organochlorine compounds and pesticides from Danish and Finnish samples have been investigated. p,p'-DDE is the dominant pollutant, beta-HCH, hexachlorobenzene, endosulfan-I, dieldrin, oxychlordane, cis-heptachlor epoxide and p,p'-DDT being the other major constituents. Their concentrations are linearly correlated between milk and placenta in similar patterns for Danish and Finnish samples. Milk samples have higher levels of these pollutants than placenta on lipid base. However, the apparently not correlated compounds, such as alpha-HCH, pentachlorobenzene, pentachloroanisole and methoxychlor, are generally accumulated more in placenta, which may suggest a tissue specific metabolic activity. Thus, depending on the compound of interest, biomonitoring may be done in placenta only or in both matrices.