Behavior of the oxygen half-saturation value and HbF content of blood of newborn infants during blood exchange transfusion

An evaluation of the HbF-content and the oxygen-half-saturation value took place in 15 newborn infants before, during and after an exchange transfusion. The initial HbF content decreased to 25% after the exchange transfusion with ACF-blood. The p50-value did not increase, as expected, but decreased dependent on the volume of the exchanged blood, caused by a quick loss of 2.3.-DPG in the ACD-blood within the first two days of storage. A normalization could be demonstrated 24 hours after the transfusion.     

Reflections on seborrheic scalp eczema and psoriasis capillitii in relation to intestinal mycoses

Stool samples of patients suffering from seborrheic eczema of the scalp, psoriasis capitis, or seborrhiasis were investigated. All patients revealed pathological flora of the bowel to a high degree, predominantly pathogenic yeasts. Therapy of the intestine seems to be of good influence to the skin disease as well.     

Medulloblastoma cells constitutively produce granulocyte colony-stimulating factor.

Granulocyte colony-stimulating factor (G-CSF) was previously shown to be produced constitutively by malignant epithelial cells and by monocytes/macrophages, fibroblasts and endothelial cells following stimulation. In this study we investigated the ability of medulloblastoma cells, representing malignant embryonal neuroectodermal cells, to produce G-CSF. Conditioned medium was freshly prepared from unstimulated explanted tumor tissue from two patients with medulloblastoma as well as from the medulloblastoma cell lines TE-671 and DAOY, and as controls normal glial cells. Following 72 hours of culture at a density of 5 x 10(5) cells/ml in RPMI 1640 with 10% FCS, the supernatants were harvested and tested for the presence of G-CSF in (1) the CFU-GM asay, (2) proliferation assay using the G-CSF dependent cell line NFS-60, and (3) Western blot analysis using an anti-G-CSF monoclonal antibody. Biological active and immunological detectable G-CSF was secreted by the medulloblastoma cell line DAOY and by one of the explanted tumor biopsies. The cell line TE-671 as well as normal glial cells did not produce G-CSF under identical culture conditions. We conclude that in addition to previously described sources of G-CSF, neuroectodermally derived medulloblastoma cells are also able to produce G-CSF constitutively. The G-CSF production was increased after stimulation with IL-1 alpha or TNF alpha. The role of G-CSF in neuroectodermal tissues remains to be further investigated.     

Pharmacokinetic behavior of ciprofloxacin both in native cardiac and porcine valves treated in glutaraldehyde

When judging a probable therapeutic success for antibiotic management of bioprosthetic endocarditis, sufficient drug levels in heterologous valve tissues play a very important role. The pharmacokinetic behavior of ciprofloxacin was investigated in native and porcine valvular tissues and compared with plasma levels during a 90- to 120-min period of surgery. Analysis was carried out by HPLC using excised valvular tissues (Hancock T 505). In all, 15-20 patients were investigated in each group. The antibiotics were administered intravenously or per os. Tissue concentrations after onset of the procedures showed ciprofloxacin plasma concentrations of 2.09-0.47 micrograms g in the native and 3.98-1.99 micrograms/g in the heterologous valvular tissues.     

Pharmacokinetic modeling of the lung burden from repeated inhalation of nickel aerosols

The saturable nature of the clearance of soluble nickel compounds from the lung was studied by repeated exposures of rats to respirable submicron-size nickel aerosols. Using Michaelis-Menten type kinetics for removal of nickel lung burdens and a constant rate of deposition, the lung nickel burdens were simulated by computer. The computer simulation was used to design a repeated exposure regimen to test further the hypothesis of saturable clearance. Male Sprague-Dawley rats were exposed for 2 h/day to nickel chloride aerosols at either 90 or 400 micrograms Ni/m3 for up to 14 days. During the 22 h between exposures and up to 3 days post-exposure rats were kept in clean air. The particle size of the aerosol ranged from 0.7 to 0.9 micron mass median aerodynamic diameter with a geometric standard deviation of 1.2-1.4. A steady-state nickel lung burden was observed at 90 micrograms/m3, as predicted from computer modeling, while lung burdens continued to increase with repeated exposure to 400 micrograms Ni/m3. The best fit for the experimental data was obtained with a maximum clearance velocity (Vmax) of 34.6 ng Ni/g X h and a Michaelis-Menten constant for transport (Kt) of 1380 ng Ni/g. The percentage of submicron nickel chloride aerosols retained in the lung was 6.9%. These data support the hypothesis of a saturable clearance mechanism for soluble nickel and provide physiological constants useful for estimating human health risks from nickel inhalation.     

Laboratory studies of vibration transmission in motor vehicle seats

Operator seats (Models 050 and 500, M?ve) were examined with vertical sinusoidal whole-body vibration (WBV) in the frequency range from 1 to 40 Hz (1.5 and 3.0 ms-2rms) and with simulated stochastic vibration of combines for the harvest of sugarcane. Six male subjects volunteered for the experiments. The WBV transmitted from the seat mounting base to the seat cushion and head were compared with data of a hard experimental seat. Interindividual differences cannot be explained by different body masses only. The iolation and main resonance of the two operator seats differed. Additional resonant peaks occurred above 6 Hz. They can cause unfavourable conditions at certain applications. The operator seats tested are probably suited for the reduction of WBV exposure on combines for the harvest of sugarcane.     

Budd-Chiari syndrome in a patient with factor V Leiden--successful treatment by TIPSS placement followed by liver transplantation.

The causes of Budd-Chiari syndrome (BCS) comprise several diseases leading to thrombophilia. One of the most common thrombophilic disorders is resistance against activated protein C, caused by a single point mutation of the factor V gene. In December 1993, a 22-year-old patient was given a diagnosis of subacute BCS with occlusion of all major hepatic veins. Placement of a transjugular intrahepatic portosystemic stent shunt led to rapid disappearance of ascites and hepatic encephalopathy. During the following two years, recurrent partial occlusions of the shunt were treated by balloon angioplasty. The cause of the BCS still being unknown, in October 1996 we performed extensive laboratory investigations concerning states of thrombophilia and found moderately elevated IgG anticardiolipin antibodies (19.7 U/ml) and a resistance against activated protein C caused by heterozygosity for a point mutation of the factor V gene (1691G-->A; factor V Leiden). As a consequence, oral anticoagulation with coumarin was initiated. In October 1997, elective liver transplantation was performed which led to disappearance of APC resistance. Moreover, IgG anticardiolipin antibodies have been negative since then. If BCS is caused by APC resistance, liver transplantation not only treats the chronic liver disease but also cures the state of thrombophilia since factor V is mainly synthesized in the liver.