The cytotoxicity of mafosfamide on G-CSF mobilized hematopoietic progenitors is reduced by SH groups of albumin--implications for further purging strategies.

The efficacy of mafosfamide purging depends on factors like incubation time, drug and erythrocyte concentration. To determine the influence of protein-bound SH groups in the incubation medium, the cytotoxicity of mafosfamide on G-CSF mobilized CD34+/- cells was evaluated by short-term culture assays and drug concentration measurements. 100 micromol/ml mafosfamide was incubated for 30 min in five buffers (PBS, PBS with 1%, 5% and 10% BSA and plasma). The mean calculated areas under the concentration-time curves (AUC) were 2489 +/- 198, 1561 +/- 286, 976 +/- 201, 585 +/- 62 and 605 +/- 196 micromol/l/min. The mean reductions of CFU-GM growth were 79.4%, 73.0%, 62.5%, 30.3%, 6.2% respectively. Similar results were obtained for BFU-E. Regression analysis showed a good correlation between cytotoxicity and AUCs (CFU-GM: r = 0.8195; BFU-E: r = 0.8207). This effect is well explained by the different concentrations of SH moieties in the incubation medium resulting in a higher drug binding capacity. The profound difference between AUCs and CFU-GMs in plasma and 10% BSA cannot be explained by the quantity of SH-groups. It is probably due to an additional enzymatic drug degeneration by the 3'-5'exonuclease subsite of plasma DNA polymerase. In conclusion, the concentration of albumin-associated SH groups strongly influences the cytotoxicity of mafosfamide. It has to be considered as a new and important aspect in ex vivo bone marrow purging.

The origin of Raynaud's phenomenon.

107 patients presenting Raynaud's phenomenon attacks were studied. It has been demonstrated by means of arteriographies that in pallid phase of Raynaud's phenomenon attacks not only the digital but also the radial ulnar and interosseous arteries are in spasm. In the cyanotic phase of Raynaud's phenomenon the natural arteriovenous anastomoses are widely open bringing about peripheral skin ischemia. On the assumption that the opening of arteriovenous anastomoses in Raynaud's phenomenon attacks is due to injury of that part of the peripheral nerve which lies in contact with the cervical vertebral column all 107 studied patients were submitted to detailed cervical vertebral column X-ray examinations. In 103 patients i.e. in 96.3% characteristic degenerative changes of cervical vertebrae were recognised. In 100 controls who never had neither Raynaud's phenomenon attacks nor cervico-brachial neuritis the same type of degenerative changes were found in 10% only. The authors presume that the Raynaud's phenomenon attacks are due to peripheral mixed nerve or their roots injury. The blue phase of Raynaud's phenomenon attacks is due to opening of arteriovenous anastomoses.

On the abdominal aortic aneurysms: pulsatile state considerations.

Pulsatile blood flow using incompressible newtonian fluid is investigated numerically in abdominal aortic aneurysm models with the aid of transient Navier-Stokes equations for axisymmetric geometry. The arterial wall is assumed to be rigid. The actual arterial pressure-velocity pulse at the abdominal aorta is used as the inlet boundary condition to the aneurysm. The corresponding velocity at every time-step is assumed to be fully developed parabolic profile at the inlet. Time-dependent formation of vortices and occurrence of stagnation zones are analyzed in this numerical study. It has been found that the distal end of the aneurysm is subjected to maximum shear stress and pressure during the entire cycle. This analysis also confirms that the mechanical forces on the arterial wall, developed by the blood flow which is pulsatile in nature, may play an important role in both development and growth of aneurysms. It has also been found that a quasi-steady state may be used to explain sufficiently the basic flow characteristic within the aneurysm. The wall shear stress in the quasi-steady state at the distal end of the aneurysm during the most adverse condition was approximately the same as in the pulsatile state for a similar situation.

[The natural history study of 208 patients with atherosclerosis of the lower extremities and diabetes mellitus]. / Studium historii naturalnej 208 chorych z miazdzyca tetnic konczyn dolnych i cukrzyca.

Analysis of 208 patients with atherosclerosis of the lower extremities and co-existing diabetes mellitus was performed to document actual symptoms, to propose a classification of extremity ischemic to localisate atherosclerotic changes and to evaluate therapeutic methods and their results. Authors suggest that to improve therapeutic results in this group of patients necessary is as follows: (a) early diagnosis of atherosclerotic ischemia of extremities, (b) proper preparing to revascularization, (c) early reconstruction of ischemic vessels, (d) good specialist controls in after surgery period.

[A rarely observed cause of renal artery stenosis and subsequent arterial hypertension]. / Rzadko wystepujaca przyczyna zwezenia tetnicy nerkowej z nastepowym nadcisnieniem tetniczym.

An atypical and very rare case of renovascular hypertension is described. Hypertension was caused by compression of the renal artery by a crus of the diaphragm.

[Infected cecostomy treated with Riebler's dental paste]. / Przetoka skórno-katnicza wyleczona za pomoca dentystycznej pasty Rieblera.

Riebler's dental paste is well known to dentists and is widely used in conservative treatment of infected dental pulp. The possibility is described of its successful use in the treatment of suppurative cutaneocaecostomy, one of the most serious surgical complications.

[Bilateral amputations after multiple vascular operations in patients with advanced ischemia of the lower extremities]. / Obustronne amputacje po mnogich operacjach naczyniowych u chorych z zaawansowanym niedokrwieniem konczyn dolnych.

In 62 patients 72 repeated multiple operations on the arteries of lower extremities were carried out. In 7 cases both lower extremities had to be amputated at mid-femoral level. The time from the first vascular operations to the amputation of the other extremity ranged from 6 months and 16 days to 8 years and 30 days (mean 5 years).

Spatially resolved high-resolution x-ray spectroscopy of high-current plasma-focus discharges.

Soft x-ray emission from a Mather-type plasma-focus device (PF-1000) operated at ∼400 kJ was measured. The high density and temperature plasma were generated by the discharge in the deuterium-argon gas mixture in the modified (high-current) plasma-focus configuration. A spherically bent mica crystal spectrograph viewing the axial output of the pinch region was used to measure the x-ray spectra. Spatially resolved spectra including the characteristic x-ray lines of highly ionized Ar and continua were recorded by means of an x-ray film. The x-ray emission of PF-1000 device was studied at different areas of the pinch.