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The ability of human gastrointestinal organisms to transform the trichothecenes 3-acetyldeoxynivalenol and nivalenol was investigated. Samples of human faeces were incubated under anaerobic conditions for 48 h with the toxins. They were then extracted and analysed for trichothecenes and metabolites. 3-Acetyldeoxynivalenol was metabolized to deoxynivalenol during the incubation period. In contrast to what has been reported for other species such as rats, mice and pigs, no de-epoxidated metabolites were detected in the faecal incubates. The toxicological significance of the difference in the intestinal ability to transform trichothecenes between species is unknown.

The capacity of pig gastrointestinal microflora to metabolise the trichothecenes 3-acetyl-deoxynivalenol (3-acDON) and nivalenol (NIV) was investigated. 3-acDON was deacetylated to DON in anaerobic incubations with pig faeces collected at different pig farms. Furthermore, both 3-acDON and NIV were metabolised to the corresponding de-epoxy metabolite in these incubates. Five pigs, in which the gastrointestinal microflora lacked the ability to transform 3-acDON and NIV to their corresponding de-epoxidated metabolites, were given low levels of DON in the feed for seven weeks. The gastrointestinal micro-organisms did not acquire the de-epoxidation ability during the seven week long exposure period. At the end of the exposure period, faeces from pigs with a known de-epoxidation ability was spread out in the pens and left for 24 hours. One week after the faeces had been spread out in the pens, the de-epoxidation ability was found in faecal incubations from four out of five experimental pigs. This change in metabolic ability of the intestinal de-epoxidation ability was not accompanied by any detectable changes in the DNA-profiles of the bacterial community composition. The results show that the intestinal de-epoxidation ability is common at pig farms in the Uppsala area, and that the ability may be transferred between pigs in a stock.

We have carried out a case-controlled study on relations between short stature (i.e. less than 156 cm tall) and problems with childbirth in Danish women. Data obtained from 182 pregnant, short women (short mothers) were compared with those obtained from a control group of 2116 pregnant women who were between 166 and 175 cm tall (control mothers). The prevalence rate for acute cesarean section was three-fold greater in short mothers than in controls, and the prevalence rate for elective cesarean section was twice as high in short mothers as in controls. Moreover, the prevalence rates of intra-uterine asphyxia, intra-uterine growth retardation and low Apgar scores were higher in babies of short mothers than in those of control mothers, despite the increased level of obstetric intervention in the former group. Since the findings show that short stature in pregnant women is an obstetrical risk factor, we recommend that it should be given attention in order to detect early signs of intra-uterine asphyxia and to apply the best form of active management of labor if necessary.

It is suggested that longitudinal compression waves are propagating parallel to the solar surface from the umbra towards the photosphere. It is shown that the line-absorption coefficient is asymmetrical, when integrated over a wavelength of the compression wave. The effect of the waves on the line profile is discussed, and it is shown that asymmetrical line profiles of the type observed in sunspot penumbrae will be produced.

To determine the absolute position of radio sources, the geometrical mounting error as well as the phase errors of the equipment must be known. In the case of a two-antenna interferometer these errors may be fairly accurately estimated if a few radio sources are observed in upper, as well as in lower, culmination.