The effect of gamma-ray irradiation on the Mn(II) speciation in Deinococcus radiodurans and the potential role of Mn(II)-orthophosphates.

D. radiodurans accumulates large quantities of Mn(II), which is believed to form low molecular weight complexes with phosphate and metabolites that protect D. radiodurans from radiation damage. The concentration of Mn(II) species in D. radiodurans during the exponential and stationary phase was determined using high-field EPR and biochemical techniques. In the exponential growth phase cells a large fraction of the manganese was in the form of Mn(II)-orthophosphate complexes. By contrast, the intracellular concentration of these compounds in stationary phase cells was less than 16 µM, while that of Mn superoxide dismutase was 320 µM and that of another, yet unidentified, Mn(II) protein was 250 µM. Stationary cells were found to be equally resistant to irradiation as the exponential cells in spite of having significant lower Mn(II)-orthophosphate concentrations. Gamma irradiation induced no changes in the Mn(II) speciation. During stationary growth phase D. radiodurans favours the production of the two Mn-proteins over low molecular weight complexes suggesting that the latter were not essential for radio-resistance at this stage of growth.

Variations in Mn(II) speciation among organisms: what makes D. radiodurans different.

The manganese(II) speciation in intact cells of D. radiodurans, E. coli, S. cerevisiae and Arabidopsis thaliana seeds was measured using high-field electron paramagnetic resonance techniques. The majority of the Mn(II) ions in these organisms were six-coordinate, bound predominately by water, phosphates and nitrogen-based molecules. The relative distribution of the different phosphates in bacteria and S. cerevisiae was the same and dominated by monophosphate monoesters. Mn(II) was also found bound to the phosphate backbone of nucleic acids in these organisms. Phosphate ligation in Arabidopsis seeds was dominated by phytate. The extent of nitrogen ligation in the four organisms was also determined. On average, the Mn(II) in D. radiodurans had the most nitrogen ligands followed by E. coli. This was attributed to higher concentrations of Mn(II) bound to proteins in these species. Although constitutively expressed in all four organisms, MnSOD was only detected in D. radiodurans. As previously reported, D. radiodurans also accumulates a second abundant Mn containing protein species. The high concentration of proteinaceous Mn(II) is a unique feature of D. radiodurans.

[Stent implantation as a palliative therapeutic measure in tumor-induced stenoses of the large veins of the body]. / Stentimplantation als palliative Therapiemassnahme bei tumorinduzierten Stenosen der grossen Körpervenen.

PURPOSE: Self-expandable metallic stents were used to treat patients with malignant venous obstructions to determine their effectiveness in producing symptomatic palliation. METHODS: 20 patients with a total of 28 tumour-induced obstructions of the superior vena cava (n = 13), the inferior vena cava (n = 4), the subclavian (n = 4), the innominate (n = 5) and the iliac veins (n = 2) were treated with self-expandable metallic stents. 38 Gianturco stents and 21 Wallstents were applied. Patients were heparinised during the procedure and up to three days afterwards. RESULTS: In all patients correct positioning of the stents was achieved. In 16 patients stent placement resulted in relief of their symptoms. In 8 patients the symptoms completely disappeared without recurrence until death as a result of tumour progression. The follow-up ranged from 10 days to 14 months. In 8 still living patients no re-obstruction occurred (follow-up average three months). In one patient thrombotic stent occlusion occurred 6 days after the procedure; the v. cava superior was reopened again by local urokinase therapy. Three patients finally developed re-occlusion due to tumour progression. In one patient stent placement was complicated by migration of the Gianturco stent one day after stent implantation and reocclusion of the subclavian vein. CONCLUSION: The application of self-expandable metallic stents in patients with malignant venous obstruction is a useful palliative therapy.

Primary sclerosing cholangitis.

Thirty patients, 18 males and 12 females, with PSC have been studied between 1972 and 1986. In nine PSC was associated with ulcerative colitis (30%), in 4 with Crohn's disease (13%) and 17 were free of any chronic bowel disease. Four of these 17 were siblings. Alkaline Phosphatase, Gamma GT, total bile acids and 7-alpha-hydroxilated bile acids were elevated in all patients. In 14 patients plasma and urinary copper as well as ceruloplasmin were studied, showing the copper in all cases and ceruloplasmin in 10 cases elevated, 4 were normal. By means of cholangiography alterations of the extrahepatic ducts, the intrahepatic ducts, and both the intra- and extrahepatic ducts were seen in 13%, 27% and 40% of the cases, respectively. Alterations of the pancreatic duct were observed by pancreatography in 21% of cases. 40% of the PSC-patients had also a Sjögren's syndrome, while 3% were associated with diabetes mellitus Type I and II, psoriasis and red lichen planus, iridocyclitis and hepatic hemangioma.

[Hepatic lesion caused by halogenated anesthetics]. / Lesión hepática por anestésicos halogenados.

Two patients has been presented to whom general anaesthesia consecutive with halogenated anesthetics has been administrated. In one of the observations the first anaesthesia was administrated with enfluorane and halothane was for the others. The two patients inured with jaundice and in one of them accompanied with hepatic insufficiency; both of them had favourable evolution. The histology of one of them show us a lesion compatible with injury caused by halogenated anaesthesia. In one of the patients appears evidences of hypersensitivity. It is request the possibility that the enfluorane could be acting as a sensibilisant drug of the hepatic injury produced by the halothane. This experience suggest us the danger already described of the consecutive use at short intervals of halogenated anesthetics. So long as fat patients are more sensible to the toxic action of these anesthetics it is suggested prevent in their cases.

Lesion hepatica por anestesicos halogenados. / Hepatic lesion caused by halogenated anesthetics

Se presentan dos pacientes a los que se les efectuan anestesias generales sucesivas con anestesicos halogenados. En una de las observaciones la primera anestesia se efectuo con enfluorano empleandose para todas las demas halotano. Los dos pacientes cursaron con ictericia acompanada, en uno de ellos de signos de insuficiencia hepatica grave; ambos evolucionaron favorablemente. La histologia de una de ellos muestra lesion compatible con injuria por anestesico halogenado. En ninguno de los pacientes hubo evidencias de hipersensibilidad. Se postula la posibilidad de que el enfluorano pudiera haber actuado como droga sensibilizante de la lesion hepatica desencadenada por el halotano. Esta experiencia sugiere el peligro ya descripto de la utilizacion consecutiva a intervalos cortos de anestesicos halogenados.Dado que los pacientes obesos son mas sensibles a la accion toxica de estos anestesicos se aconseja evitarlos en ellos

Lesion hepatica por anestesicos halogenados. / Hepatic lesion caused by halogenated anesthetics

Se presentan dos pacientes a los que se les efectuan anestesias generales sucesivas con anestesicos halogenados. En una de las observaciones la primera anestesia se efectuo con enfluorano empleandose para todas las demas halotano. Los dos pacientes cursaron con ictericia acompanada, en uno de ellos de signos de insuficiencia hepatica grave; ambos evolucionaron favorablemente. La histologia de una de ellos muestra lesion compatible con injuria por anestesico halogenado. En ninguno de los pacientes hubo evidencias de hipersensibilidad. Se postula la posibilidad de que el enfluorano pudiera haber actuado como droga sensibilizante de la lesion hepatica desencadenada por el halotano. Esta experiencia sugiere el peligro ya descripto de la utilizacion consecutiva a intervalos cortos de anestesicos halogenados.Dado que los pacientes obesos son mas sensibles a la accion toxica de estos anestesicos se aconseja evitarlos en ellos

Lesión hepática por anestésicos halogenados. / [Hepatic lesion caused by halogenated anesthetics]

Two patients has been presented to whom general anaesthesia consecutive with halogenated anesthetics has been administrated. In one of the observations the first anaesthesia was administrated with enfluorane and halothane was for the others. The two patients inured with jaundice and in one of them accompanied with hepatic insufficiency; both of them had favourable evolution. The histology of one of them show us a lesion compatible with injury caused by halogenated anaesthesia. In one of the patients appears evidences of hypersensitivity. It is request the possibility that the enfluorane could be acting as a sensibilisant drug of the hepatic injury produced by the halothane. This experience suggest us the danger already described of the consecutive use at short intervals of halogenated anesthetics. So long as fat patients are more sensible to the toxic action of these anesthetics it is suggested prevent in their cases.