Myomatous erythrocytosis syndrome: further proof for the pathogenic role of erythropoietin.

BACKGROUND: Myomatous erythrocytosis syndrome is defined by the combination of erythrocytosis, myomatous uterus and persistent restoration of normal haematological values after hysterectomy. A pathogenic role of erythropoietin is suggested by clinical and experimental data. CASE REPORT: A postmenopausal patient is described with the classical clinical signs of the myomatous erythrocytosis syndrome. During hysterectomy we demonstrated a large gradient between the erythropoietin levels in the uterine vein and artery, providing direct evidence for in vivo erythropoietin production by the myomatous uterus. CONCLUSION: While erythropoietin and its receptor are consecutively expressed in normal and myomatous uterine tissue, it is amazing that erythrocytosis occurs so rarely in such a frequent disorder as uterine myomatous. We strongly advocate cytogenetic examination of the myomatous tissue of subsequent patients with this entity.

Characterization of enzymes involved in biotransformation of polycyclic aromatic hydrocarbons in terrestrial isopods.

Little is known about the capacity of terrestrial invertebrates to transform organic soil pollutants such as polycyclic aromatic hydrocarbons (PAHs). Studies were designed to characterize microsomal mixed function oxygenase and accompanying conjugation enzymes from the hepatopancreas of the terrestrial isopods Porcellio scaber and Oniscus asellus using pyrene and 1-hydroxypyrene as model substrates. The hydroxylation of pyrene and the formation of pyreneglucoside and pyrenesulfate appeared to be sensitive measures for the activity of cytochrome P450 aryl hydrocarbon hydroxylase (AHH), uridinediphosphateglucosyltransferase (UDPGT), and aryl sulfotransferase (ST), respectively. Treatment with the antibiotic riphampicine demonstrated that the enzyme activities originate from the animals themselves and not from symbiotic microflora present in the hepatopancreas and the gut. In both species, ST has a very high affinity for 1-hydroxypyrene with Km values two orders of magnitude lower than that of UDPGT. The Vmax values of UDPGT, however, are 10- to 20-fold higher than that of ST. Taking the P450 activities into consideration, both species are expected to transform PAHs in an equally effective way. When the isopods were fed with food containing benz[a]pyrene and 3-methyl-cholanthrene, none of the enzyme activities appeared to be inducible except for a small enhancement of UDPGT in O. asellus. Our findings indicate that terrestrial isopods have a high, noninducible capacity for biotransformation of PAHs and that the sulfate conjugation pathway is as important as the carbohydrate conjugation pathway. This conclusion is consistent with the low body residues of parent PAHs found in the field.

Spatial distribution of trace metals in sediments from urban streams of Semarang, Central Java, Indonesia.

Elevated environmental concentrations of metals are usually associated with the impact of urbanization. The present study is focused on metal contamination in urban sediments. A field survey was carried out to determine the distribution of four metals, i.e., cadmium (Cd), lead (Pb), copper (Cu), and zinc (Zn), in the coastal urban area of Semarang, Central Java, Indonesia. Sediment samples were collected from 101 grids of 2x2 km. To map the spatial distribution of these metals, concentrations of each metal were plotted against the corresponding grid coordinate. Cd was below the detection limit (<0.03 microg/g) in all samples, whereas concentrations of Pb, Zn, and Cu fell into a wide range. Frequency distributions of Pb, Zn, and Cu concentrations indicated a similar pattern, in which the major proportion of the sites had a low metal concentration. Some sites, however, had extremely high metal concentrations, Zn up to 1257 microg/g, Pb up to 2666 microg/g, and Cu up to 448 microg/g. The data were used to define background concentrations for sediments in coastal zones of Indonesia ("reference values"). The proposed reference values are 25.6 microg/g, 132.2 microg/g, and 40.7 microg/g, respectively, for Pb, Zn, and Cu. The degree of metal contamination of each individual site was classified according to the calculated value of a combined pollution index, W. Four categories of the degree of metal contamination were proposed, i.e., unpolluted, slightly polluted, polluted, and heavily polluted. Based on this classification, from 101 sites investigated in the greater Semarang area, 51 are unpolluted, 36 slightly polluted, 9 polluted, and 5 heavily polluted.

Associations between trace metals in sediment, water, and guppy, Poecilia reticulata (Peters), from urban streams of Semarang, Indonesia.

The present study aims to answer the question whether the amount of metal in aquatic biota reflects the concentrations in the sediment and water, and whether the physico-chemical properties of the water and sediment have any influence on the suspected relationship. A study was made of 101 small streams in the city of Semarang, Central Java, Indonesia. Data on fish occurrence in 63 streams of the greater Semarang indicated that the guppies did not avoid the highly polluted sites. No significant difference in body weight between sites was found. Significant differences were found in metal body concentrations (Pb and Zn) between fish collected from sites with different degrees of pollution. A significant declining trend of Pb concentrations with increasing organism size was observed, whereas for two other metals, Zn and Cu, the concentrations did not depend on the body weight. Apparently, body concentrations of these two metals are regulated and maintained at a certain concentration. For the relationships between metal concentrations in water, sediment and fish, water and sediment parameters, and fish dry weight, the presence of significant multiple correlations and bivariate correlation (in 17 of 91 pairs of variables) indicated that, in general, abiotic parameters and body size had no influence on the metal flux from sediment to water, and into fish. Results of partial correlation analyses further suggested that metal concentrations in the sediments were the most important factor governing the metal body concentrations of fish. The present study indicates that the guppy Poecilia reticulata from urban streams is a potential bioindicator for urban metal pollution, especially with respect to their (1) spatial distribution over sites of all pollution regimes and (2) variation in metal accumulation levels reflecting the degree of pollution.

Breech delivery in very preterm and very low birthweight infants in The Netherlands.

OBJECTIVE: To study the relation between various perinatal factors and the sequelae of very preterm birth, applying logistic regression analysis. DESIGN: In a nationwide collaborative study in the Netherlands, perinatal and follow up data were collected on 899 liveborn singleton nonmalformed infants with gestational age less than 32 weeks or birthweight less than 1500 g born in 1983. MAIN OUTCOME MEASURES: Neonatal mortality rate and total handicap rates (minor and major) in surviving children at two years and five years of age. RESULTS: Comparing breech with vertex presentation, the odds ratio for neonatal mortality (adjusted for duration of pregnancy, birthweight, maternal hypertension and prolonged rupture of membranes) is 1.6 (P < 0.05). Comparing abdominal versus vaginal delivery, the odds ratio indicates equal risks. When breech and vertex presentation are analysed separately it appears that breech presenting infants have a significantly lower mortality risk when born by caesarean section compared with vaginal delivery. However, comparing abdominal versus vaginal delivery in breech presentation, the odds ratio for handicap at five years (0.9) is not significantly different from 1. CONCLUSION: The data presented suggest a reduced neonatal mortality rate in breech presenting infants born by caesarean section but because of the observational design of the study the statistical analysis described only identifies a possible trend and cannot prove the issue.