alpha-L-rhamnosidase of Sphingomonas sp. R1 producing an unusual exopolysaccharide of sphingan

A soil bacterium with alpha-L-rhamnosidase was isolated from a cumulative mixed culture containing a polysaccharide of gellan as a carbon source and identified to be Sphingomonas paucimobilis, known as a potent producer of gellan. The isolate (designated Sphingomonas sp. R1) produced an unusual exopolysaccharide of sphingan (denoted HWR1) distinct from gellan. The rhamnose in gellan was replaced with mannose in HWR1. The bacterium had a peculiar cell surface covered with many complicated plaits. alpha-L-Rhamnosidase purified from Sphingomonas sp. R1 grown in the presence of naringin was a monomer with a molecular mass of 110 kDa and most active at pH 8.0 and 50 degrees C. The enzyme required divalent metal ions for the activity and released L-rhamnose from various rhamnosyl glycosides.     

The effect of probucol on oxidized cholesterol disposition in hyperlipidaemic patients

Hardly any part of the legal regulations on absenteeism and incapacity for work has remained unchanged since 1993 in the Netherlands. The system is becoming increasingly complicated. The essence of the changes is that employers' responsibility has greatly increased. The new regulations mean a transition from industrial health care to Factories Act services and from the industrial insurance board to implementing organs. The legislator emphasizes the evaluation of what people with health disorders are still able to do. Prevention of absenteeism/ incapacity for work and reintegration are given great attention. Treating physicians should not let the complicated regulations keep them from fulfilling their tasks concerning sick employees, since it is increasingly in the patient's interest that chronicity be prevented whenever possible.     

FGF-10 is a chemotactic factor for distal epithelial buds during lung development

BACKGROUND: We investigated the ability of a variety of growth factors to regulate the differentiation of prostatic fibroblasts into smooth muscle cells. METHODS: Smooth muscle actin levels were monitored by immunoblot analysis and immunocytochemistry. Proliferation was measured in clonal growth assays and by cell counts. RESULTS: We determined that TGFbeta inhibited proliferation and induced smooth muscle differentiation of stromal cells derived from prostatic adenocarcinomas, as we previously reported for cells derived from the normal peripheral zone. Basic FGF, EGF, TGFalpha, and PDGF, but not IGF, retinoic acid, 1,25-dihydroxyvitamin D3, or androgen, attenuated induction of differentiation by TGFbeta, by a mechanism apparently unrelated to proliferation. CONCLUSIONS: Regulation of growth and differentiation occurs equivalently in prostatic stromal cells derived from adenocarcinomas and normal peripheral zone. TGFbeta is a potent inducer of the smooth muscle phenotype. Basic FGF, EGF and/or TGFalpha, and PDGF attenuate TGFbeta's activity, and promote a fibroblastic phenotype. Our studies provide an in vitro model system in which fibroblastic or smooth muscle cells can be promoted, maintained, and investigated in a defined manner. The results suggest that the ratio of fibroblasts to smooth muscle cells in the stroma reflects the relative levels of growth factors, which may be altered in diseased states.     

Presence of dioxins in human follicular fluid: their possible stage-specific action on the development of preimplantation mouse embryos

Examination of human follicular fluid revealed the presence of polychlorinated dibenzodioxins (PCDDs) and dibenzofurans (PCDFs) at concentrations of approximately 1 pg/ml (0.01 pg TEQ/ml). To study their possible action, two-cell mouse embryos were cultured in the presence of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) at concentrations between 0.5 and 100 pM and evaluated at 24-h intervals for their development to the eight-cell and blastocyst stages. The percentage of eight-cell embryos exposed to TCDD at 1, 2, and 5 pM concentrations was significantly lower than that of controls. However, blastocyst formation of the surviving eight-cell embryos was accelerated, with the number of cells in the blastocysts increased in a dose-dependent manner. Findings suggest that PCDDs and PCDFs may be present in human reproductive fluid and may exert some stage-specific effects on early embryonic development.     

Anodic characteristics of amorphous nickel-value metal alloys containing small amounts of platinum group elements in 0.5 M NaCl

By utilizing the characteristics of amorphous alloys capable of possessing specific electrocatalytic activity and corrosion resistance by alloying and surface activation treatment, an attempt was made to find amorphous alloys which are active as the anode material for production of sodium hypochlorite by electrolysis of seawater. Amorphous Ni-Nb and Ni-Ta alloys containing only 0.5–2.0 at % palladium and other platinum group metals showed a very high activity for chlorine production by electrolysis of 0.5M NaCl at 30°C when they were previously immersed in 46% HF for surface activation. The current efficiency of these surface-activated alloys for chlorine evolution considerably exceeded that of the currently used, most active Pt-Ir/Ti electrode for electrolysis of seawater. The surface activation treatment resulted in preferential dissolution of alloy constituents unnecessary for the electrocatalytic activity, i.e. nickel and valve metals, with a consequent enrichment of electrocatalytically active platinum group elements in the surface-activated layer. The corrosion weight loss of the surface-activated amorphous alloys under the steady state conditions for chlorine production was undetectable by a microbalance.     

A study of various complications in arterial infusion chemotherapy

Complications of arterial infusion chemotherapy were analyzed in 261 cases from December 1983 to December 1993 in our department. Their complications involved nausea and vomiting (40.6%), bone marrow suppression (33.3%), liver dysfunction (20.3%), gastric and duodenal ulcer (9.6%) and so on. Complications involving an implantable device were hepatic arterial obstruction (29.1%), reservoir obstruction (5.7%), dislocation of catheter (4.6%), infection of catheter (3.8%), and obstruction of catheter (1.9%). In another cases with hepatic arterial obstruction, we performed arterial infusion in another artery as a bypass or stopped the infusion. In cases with obstruction of catheter not able to be reopened, we reinserted the catheter. An obstructed and/or infected reservoir was removed or replaced. Nausea and vomiting were found in 46.3% of FAM arterial infusion method (FAM) cases, in 53.3% of 5-FU persistent arterial method (5-FU) + FAM cases, and in 40.5% of intermittently persistent arterial method (IP) cases. Gastric and duodenal ulcer were noted in 9.8% of FAM, 13.3% of 5-FU + FAM, and 8.1% of IP cases. There were no significantly statistical differences between the methods. Hepatic arterial obstruction predominantly occurred in 32.4% of IP and 26.7% of 5-FU + FAM and bone marrow suppression was predominant in cases in which ADM was used. The duration of obstruction after administration was 154.0 +/- 117.4 days on average (21-455 days). Complications of hepatic arterial infusion chemotherapy are based on various causes which can be managed for prevention. We intend to enhance safety and assure the greater effectiveness of hepatic arterial chemotherapy.     

Ontogeny of alpha-crystallin subunits in the lens of human and rat embryos

The distribution of alpha A- and alpha B-crystallin in the developing lens of human (Carnegie stages 13 to 23) and rat embryos (embryonic days E11 to 18) was examined immunohistochemically. In a human embryo at stage 13, the lens placode was already immunoreactive to alpha B-crystallin, but not to alpha A-crystallin. At stage 15, the lens vesicle was intensely immunoreactive both to alpha A- and alpha B-crystallin. From stages 16 to 23, the lens epithelial cells and fiber cells were immunoreactive to alpha A- and alpha B-crystallin. In rat embryos, alpha A-crystallin appeared in the lens pit at E12, and alpha B-crystallin appeared in the elongating lens fiber cells at E14. From E15 to E18, the lens epithelial cells and fiber cells were immunoreactive to alpha A-crystallin. The lens fiber cells were also immunoreactive to alpha B-crystallin, but the epithelial cells were not. These findings suggest that alpha B-crystallin appears earlier than alpha A-crystallin in the human lens, but at a later period than alpha A-crystallin in the rat lens. alpha B-Crystallin was not detected in the epithelial cells of the rat lens, but was persistently present in the epithelial cells of the human lens.     

Induction of transplantation immunity by dansylated tumor cells

Tumor cells were coupled with fluorecent dansyl group in aqueous medium by dansyl chloride-cycloheptaamylose complex (CDC) without destruction of the cells. C57BL/6 mice and Donryu rats pretreated respectively with dansylated EL4 leukemia cells and with dansylated Yoshida sarcoma cells acquired transplantation immunity to the corresponding tumor cells. Serum and spleen cells obtained from EL4 immune mice showed cytotoxicity to EL4 cells but not to other allogeneic leukemia cells. Hapten-specific cytotoxicity of immune serum and spleen cells was not observed in the present immune system.