Hepatic calcifications in a fetus with trisomy 9 that underwent cordocentesis

Foci of calcification were observed at autopsy in the liver of a fetus with complete trisomy 9 on which two cordocenteses had been performed. It is suggested that liver calcifications are a possible complication of the procedure. As several other cases of calcifications in the liver and other organs of fetuses with autosomal trisomies have been described without a history of cordocentesis, further studies should be carried out to determine whether fetuses with chromosomal anomalies are more prone to thrombus formation and embolization.     

Chorionic villus sampling—short-term versus long-term culture in a subtle 2; 18 translocation

Prenatal diagnosis on chorionic villous tissue was performed for a woman with the karyotype 46,XX,t(2;18)(q32;q12)—a subtle ‘difficult’ translocation. The case illustrates the necessity of good quality cytogenetics for accurate prenatal diagnosis. For chorionic villi this can be obtained only with long-term culture.     

Serum PAPP-A measurements in first-trimester screening for Down syndrome

Serum PAPP-A measurements taken from 254 women in the first trimester are reported. Eleven chromosomal abnormalities were detected. The mean serum PAPP-A levels in cases of Down syndrome were 0.44 MOM at 9 weeks gestation, 0.15 MOM at 10 weeks, and 0.29 MOM at 11 weeks. The PAPP-A level at 10 weeks was below those of pregnancies which aborted spontaneously. At 11 weeks, the pregnancies with Down syndrome recorded the lowest PAPP-A levels at that gestation. On this small sample, offering chorionic villus sampling to women with singleton pregnancies and a PAPP-A level below 0.3 MOM (approximately 6.5 per cent of this at-risk group) would have detected all the Down syndrome fetuses at 10 weeks and 50 per cent at 11 weeks without selecting those cases destined to abort. This suggests that serum PAPP-A should continue to be investigated as a potential first-trimester screening test for Down syndrome.     

Petroleum waste biodegradation with porous biomass support system (PBSS) on rotating biological contactor

A laboratory scale study was conducted to assess the feasibility of the new coupling of rotating biological contactor (RBC) plus porous biomass support system (PBSS) using polyurethane foam as porous support media to biodegrade petroleum refinery wastewater. Polyurethane foam was attached on disks of two four-stage laboratory scale cascade connected RBC units.The two RBC units were operated simultaneously at different but constant, flowrates giving hydraulic loading rates of 0.01, 0.02, 0.03, 0.04 m3/m2/d in two runs keeping the same rotational speed 10 r/min throughout. Organic loading was a less controllable factor in this study.For all of the hydraulic loadings, it was found that the removal efficiency of total chemical oxygen demand (TCOD) and oil were above 80 percent. Ammonia nitrogen and phenol removal were above 90 and 80 percent respectively. The maximum biomass concentration within polyurethane foam was about 30 g/m2 in the first stage for 0.03 m3/m2/d hydraulic loading.The results show that t     

Prenatal diagnosis of cleft lip and palate by ultrasound

Bilateral cleft lip and cleft palate can be diagnosed by ultrasonography prior to 20 weeks of pregnancy. The anomaly produces an abnormal facial profile and, on cross-section, the clefts in the maxilla are demonstrable. The method is illustrated by sonograms from a fetus in which the defect was diagnosed before trisomy 13 became known by karyotyping.     

Protozoan colonization on artificial substrates in relation to water quality in a tropical Indian harbour.

A field study was conducted to evaluate the protozoan colonization patterns on artificial substrates in relation to organic pollution within a tropical harbour. The composition of protozoans and their succession rates on artificial substrates(polyurethane foam units) were compared between two field stations(A and B), and their presence were considered with regards to the prevailing water quality conditions at the study sites. Altogether 44 genera of flagellates and ciliates were documented. The common genera of flagellates encountered included Monas, Polytoma, and Chromalina. Among the ciliates, the predominant genera were Tetrahymena, Vorticella, Lagymophyra, and Heloiphyra. These groups exhibited characteristic successional patterns in relation to ambient water quality. At Station A, located close to the sewage outfall, the water quality parameters included poor Secchi-disc transparency(0.48 m), dissolved oxygen of 1.93 mg/ml, salinity of 18 psu, and temperature 31.3 degrees C. Here, the nanoflagellates (spumella) colonized first, followed by microcilliate(Tetrahymena) and sessile form(Vorticella). Station B, located on the seaward side, was characterized by relatively less-stressed environmental conditions with transparency 1.85 m and dissolved oxygen value of 6.04 mg/ml. Salinity of 27.27 psu, and mean temperature of 30 degrees C were recorded at "B". At this station, the nanoflagellate Polytoma was first documented to colonize on the substrates, followed by microcilliate(Lagynophrya) and suctorid(Heliophyra). These findings support the use of protozoans as indicator species for evaluating the hazards posed by organic pollution to natural estuarine communities.     

Biodegradation of aliphatic and aromatic hydrocarbons by natural soil microflora and pure cultures of imperfect and lignolitic fungi

The biodegradation of aliphatic and aromatic hydrocarbons by natural soil microflora and seven fungi species, including imperfect strains and higher level lignolitic species, is compared in a 90-day laboratory experiment using a natural, not-fertilized soil contaminated with 10% crude oil. The natural microbial soil assemblage isolated from an urban forest area was unable to significantly degrade crude oil, whereas pure fungi cultures effectively reduced the residues by 26-35% in 90 days. Normal alkanes were almost completely degraded in the first 15 days, whereas aromatic compounds (phenanthrene and methylphenanthrenes) exhibited slower kinetics. Aspergillus terreus and Fusarium solani, isolated from oil-polluted areas, produced the more efficient attack of aliphatic and aromatic hydrocarbons, respectively. Overall, imperfect fungi isolated from polluted soils showed a somewhat higher efficiency, but the performance of unadapted, indigenous, lignolitic fungi was comparable, and all three species, Pleurotus ostreatus, Trametes villosus and Coriolopsis rigida, effectively degraded aliphatic and aromatic components. The simultaneous, multivariate analysis of 22 parameters allowed the elucidation of a clear reactivity trend of the oil components during biodegradation: lower molecular weight n-alkanes > phenanthrene > 3-2-methylphenanthrenes > intermediate chain length n-alkanes > longer chain length n-alkanes > isoprenoids approximately 9-1-methylphenanthrenes. Irrespective of the individual degrading capacities, all fungi species tested seem to follow this decomposition sequence.     

Respiratory physiology in summer diapause embryos of the neustonic copepodAnomalocera patersoni

The respiratory physiology of summer diapausing eggs of the neustonic copepodAnomalocera patersoni, maintained under constant temperature (13 °C) and light (12 h light:12 h dark) conditions, was characterized by a bell-shaped curve, with low O₂ uptake levels at the beginning of dormancy. This was followed by a steady rise in O₂ consumption with maximum levels of 0.002 l O₂ embryo^–1 h^–1 70 d after spawning. A slow diminution in O₂ uptake then occurred until Day 150 when minimum values of 0.0003 l O₂ embryo^–1 h^–1 were recorded, coinciding with the hatching of the first embryos. Embryos continued to hatch asynchronously up to 360 d from the moment of egg laying. When eggs were subjected to 20 °C, the respiratory activity was almost three times higher than at 13 °C, even though both respiratory curves were similar. The elevated metabolism in eggs kept at 20 °C led to death of the embryos possibly due to a total depletion of metabolic reserves. ATP content also differed at the two temperatures. Diapause eggs kept at 20 °C showed no rapid rise in ATP content as opposed to those kept at 13 °C. The results of temperature shock experiments, in which eggs were first kept at winter temperatures for several weeks, after which the temperature was raised to 20 °C for another number of weeks prior to a second period of chilling at 13 °C, showed that as long as embryos were kept at 20 °C no hatching occurred. By contrast, hatching was observed after 10 d following the resumption of winter temperatures, suggesting that low environmental temperatures are an essential prerequisite for hatching of these eggs. The type of diapause inA. patersoni differs considerably from the one described in insects and in another neustonic copepod,Pontella mediterrana. In this case, there is a U-shaped respiratory curve with greatest O₂ consumption prior to the onset or upon breaking of diapause. Differences in the two types of diapause seem to involve not only differences in O₂ consumption levels but also in the sequence of metabolic changes with time and the metabolic requirements during sommer and winter dormancy.     

Influence of reduced dietary calcium on the accumulation and effects of lead, cadmium, and aluminum in birds

The influence of low dietary calcium on the accumulation and effects of dietary lead, cadmium and aluminum was examined in zebra finches and ring doves. In zebra finches fed a diet containing 0.3% Ca, the hepatic and renal accumulation of lead was enhanced approximately 400% and of cadmium about 150-200%, compared to birds fed a 3.0% Ca diet. Low dietary Ca also caused bones of female finches to lose an average of about 60% of their normal Ca content. Loss of bone-Ca was also observed in male finches, but was less than in females. In reproductively active ring doves, low (0.4%) dietary Ca enhanced the accumulation of lead and cadmium, but not of aluminum, compared with accumulation in doves consuming a 2.0% Ca diet. Enhanced accumulation of lead and cadmium was accompanied by increased synthesis of the metal-binding protein metallothionein and by greater inhibition of delta-aminolevulinic acid dehydratase activity. These results indicate that, under conditions of reduced dietary Ca availability, such as can occur in acid-impacted environments, wild birds risk increased uptake of certain toxic metals and may accumulate toxic concentrations of these metals more rapidly. Researchers should take account of dietary Ca levels when interpreting results of dosing studies in which metals such as lead and cadmium are administered to birds.