Fetal phenotype of Prader–Willi syndrome due to maternal disomy for chromosome 15

Prader–Willi syndrome (PWS) results from either paternal deletion of 15q11–q13, or maternal uniparental disomy (UPD) of chromosome 15 or imprinting center mutation. Prenatal diagnosis of PWS is currently indicated for chromosomal parental translocation involving chromosome 15 and for decreased fetal movements during the third trimester of gestation. Here we present the prenatal diagnosis of PWS during the first trimester of gestation and autopsy findings. Chorionic villus sampling (CVS) was performed for advanced maternal age at 13 weeks' gestation. CVS showed mosaicism including cells with a normal karyotype and cells with trisomy 15. Amniocentesis showed cells with a normal karyotype. Molecular analysis demonstrated that the fetus had a typical PWS abnormal methylation profile and maternal disomy for chromosome 15. Fetal ultrasound examination showed slightly enlarged lateral ventricles and hypoplasic male external genitalia without intra-uterine growth retardation. The autopsy showed a eutrophic male fetus with facial dysmorphy, hypoplasic genitalia, abnormal position of both feet and posterior hypoplasia of the corpus callosum. This report points out that in a karyotypically normal fetus with ambiguous male external genitalia and cerebral anomalies, extensive cytogenetic and molecular biology studies are strongly recommended because of risk of PWS. Copyright © 2003 John Wiley & Sons, Ltd.     

A study of the growth and decay of cigarette smoke NOx in ambient air under controlled conditions

The amount of NO₂ and NO produced by the machine smoking of cigarettes was determined for 15 commercial Canadian brands. Average yield of NO was 1.44 μmoles or about 13% of the average reported for American cigarettes. Levels of NO₂ were less than 12% of NO and were probably due to the oxidation of NO. In order to assess the contribution of tobacco smoke to levels of NO in ambient air, 5 brands of cigarettes were smoked in 27 cubic meter controlled environment room. Ventilation conditions were either 2.5 or 5.0 air changes per hour (ACH) and each experiment was replicated 3 times for a total of 30 experiments. Ventilation rates of 0.3 and 1.5 ACH were also selected in a second series of experiments in which only one brand of cigarette was smoked. Least squares estimates for the effective ventilation rates were obtained in the usual manner after linearizing the decay portion of the NO time curve. In each of the experiments, the regression explained at least 95% of the variation in the levels of NO with time. Loss of NO due to factors other than ventilation appeared to be constant within experimental error and averaged 2.22 ACH. Equilibrium values for NO were grossly underestimated when results from currently accepted proecedures for smoke analysis were used in modeling the growth and decay of NO. Goodness-of-fit was improved when equilibrium values were estimated based on observed levels in ambient air. This approach may be more suitable for evaluating the potential contribution of cigarette smoke to levels of indoor air pollutants.     

Earthquake hazard assessment after Mexico (1985)

The 1985 Mexican earthquake ranks foremost amongst the major earthquake disasters of the twentieth century. One of the few positive aspects of the disaster is that it provided massive quantities of data that would otherwise have been unobtainable. Every opportunity should be taken to incorporate the findings from these data in earthquake hazard assessments. The purpose of this paper is to provide a succinct summary of some of the more important lessons from Mexico. It stems from detailed field investigations, and subsequent analyses, conducted by the author on the behalf of reinsurance companies.     

Design and validation of a practical index for trauma assessment

In the past 20 years a variety of indices have been suggested for measuring the severity of trauma, however none of them meets the requirement of being a simple and objective instrument that can be utilized efficiently by lay persons and providers of health services without previous experience in triaging. A new system has been proposed which meets this requirement and which has been validated with 197 injured persons at the emergency ward of the Valle University Hospital in Call, Colombia. The instrument showed a high level of concordance with the conventional triaging method and classifies victims into four categories: critical with recovery unlikely, critical but recoverable, moderately serious, and ambulatory. There is discussion on the reliability of this instrument and it is recommended that it be validated with victims from larger disasters. Regardless, it has the advantage of being specific and free of the subjectivity that characterizes other indices.     

Surveillance for adverse health effects following a chemical release in west virginia

On 11 August 1985, a large inadvertent release occurred from a chemical manufacturing plant in Institute, West Virginia. The emission was related to overheating of a storage tank that contained chemicals for the production of aldicarb, a cholinesterase inhibiting pesticide. As a result of this emission, 136 persons were treated in five local emergency rooms, 29 of whom were hospitalized for one or more days, mostly for observation. No fatalities resulted. Interviews with treated persons and non-treated community residents confirmed that the health effects were transient and compatible with exposure to irritating vapors rather than with exposure to methyl isocyanate (a chemical used in the process) or to aldicarb. Only 5% of the treated persons and 5% of the community residents surveyed were adequately warned of the emission by the plant siren. Because persons in the nearby community are potentially vulnerable to chemical injury, we recommend the development of an improved warning system, a formal evacuation procedure, and other measures to limit exposure of persons in this area in the event of a future release.     

The importance of free amino acids to the energy metabolism of eggs and larvae of turbot (Scophthalmus maximus)

A study was undertaken to establish the role of free amino acids (FAA) in aerobic energy dissipation in embryos of turbot (Scophthalmus maximus) which contain an oil globule in the egg. Laboratory-reared developing eggs and larvae (15°C, 34 salinity) were measured for oxygen uptake, ammonia excretion, contents of FAA, protein, and ammonium, and volumes of yolksac and oil globule. Newly spawned eggs from different batches contained 55 to 90 nmol egg^–1 of FAA. Resorption of FAA occurred in parallel with the consumption of yolk. Resorption of the oil globule, however, occurred predominantly after hatching and mainly after yolk resorption. The combined data suggest that approximately 70% of the FAA are utilized as an energy substrate, while the rest are polymerized into body proteins. FAA become a significant energy substrate in the early egg stage and account for 100% of the aerobic energy dissipation 2 d after Fertilization then decrease to ca. 60% at the time of hatching. Lipids derived from the oil globule seem to be the main fuel after hatching and account for ca. 90% of the energy dissipation at the onset of first-feeding. Thus, the energetics of fish embryos which contain an oil globule seems to be different from those that depend exclusively on the nutritional reserves of the yolk.     

Planktonic ciliates in Southampton Water: abundance,biomass, production,and role in pelagic carbon flow

The abundance and biomass of marine planktonic ciliates were determined at monthly intervals at two stations in Southampton Water between June 1986 and June 1987. The two stations, an outer one at Calshot and an inner one at N. W. Netley, were subject to differing marine and terrestrial influences. The potential ciliate production at cach station on each visit was estimated from these data. Enumeration of ciliates and measurements of biovolume were performed on Lugol's iodinepreserved samples and potential production was calculated using a predictive relationship based on temperature and cell volume. Heterotrophic ciliate abundance and biomass were greatest at both stations during spring and summer months, with respective maxima of 16x10³ organisms 1^-1 and 219 g Cl^-1 recorded at N. W. Netley. Estimates of the potential production of the ciliate community ranged from <1 to 18 g Cl^-1 d^-1 at Calshot and <1 to 141 g Cl^-1 at N. W. Netley, with annual values of 2 and 9 mg Cl^-1 yr^-1, respectively. Abundances, biomass and potential production estimates were generally greater at N. W. Netley than at Calshot. Carbon flow through the ciliate community was assessed using annual production values from both this study and the literature. The annual ciliate carbon requirement was equivalent to 9 and 11% of annual primary production at Calshot and N. W. Netley, and potential annual ciliate production was equivalent to 34% and >100% of the energy requirements of metazoan zooplankton at these locations, although comprising only 8 and 10% of their available food.     

Calmodulin as a modulator of NaCl transport in the posterior salt-transporting gills of the Chinese crab Eriocheir sinensis

The possible involvement of calmodulin-dependent processes in the control of Na⁺ and Cl^- transport pathways has been investigated on isolated, perfused preparations of salt-transporting posterior gills of the euryhaline Chinese crab Eriocheir sinensis (collected near Emden, Germany in autumn 1990). The anti-calmodulin phenothiazine drugs Chlorpromazine and Trifluoperazine induced depolarization of the transepithelial potential only when added to the serosal bathing saline (socalled in). This effect is best interpreted by assuming a disturbance of the conductive Cl^- pathways located at the baso-lateral side of the epithelium. In agreement with that conclusion is the fact that Trifluoperazine inhibits the Cl^- transepithelial influx. Trifluoperazine also induces inhibition of the Na⁺ influx when added either to the incubation (out) or to the perfusion (in) medium. These results indicate inhibitory effects of the anticalmodulin drug on both the Na⁺/K⁺ pump and leak system located at the serosal side and on the Na⁺/H⁺ exchange located at the apical side of the epithelium.