Characterization of type I 5 alpha-reductase activity in DU145 human prostatic adenocarcinoma cells

Each amino acid is represented by a vector of numerical measurements for the attributes of volume, area, hydrophilicity, polarity, hydrogen bonding, shape, and charge. Inter-residue distances are then calculated according to common metrics, and we introduce a new clustering objective function derived from information-theoretic considerations. The arguments of the function are the inter-object distances of the things to be clustered: in this case the amino acids. By means of approximating the solution of an integer programming problem, then, the residues are partitioned into clusters. The clusters obtained are compared with groups obtained in substitution/mutation studies and found to be similar. Thus, probably the strongest and most objective evidence to date is supplied for believing that physico-chemical properties account for the viability of substitutions and that the important similarities/differences are explained by a relatively small and simple set of properties.     

A high-speed vector-controlled spindle motor drive with closedtransition between with encoder control and without encoder control

A 40000-r/min vector-controlled induction motor drive is introduced. The vector control of induction motors has been widely accepted in spindle drives of machine tools where they replace conventional DC motors because of the low maintenance requirements. Another important feature of the AC spindle drive is its high-speed capability. The magnetic encoder is most widely used as the speed detector because it is suited for use in an adverse environment. However, the magnetic encoder with high resolution and a high S/N ratio loses the output pulses at extremely high speed. In the drive system introduced, the conventional vector control is used in the low-speed range, and the vector control without the encoder is used in the high-speed range. Close transition between two modes is made without interrupting the operation     

Malignoma versus bacterial spondylodiscitis: value of spinal MRI for the differential diagnosis in an emergency situation. Description in an acute case with progressive paraplegia

BACKGROUND: For the radiation oncologist in an emergency situation with acute progressive paraplegia distinguishing between benign versus malignant vertebral compression fracture without known malignoma may cause a severe diagnostic problem, when a rapid therapeutic decision is required. PATIENT AND METHOD: A case of an elderly diabetic patient with acute onset of a progressive neurologic deficit is reported. No malignancy was known so far. The CT of the spine showed a destruction of the 7th and 8th thoracic vertebral body with compression of the spinal cord. The patient was referred to the radiotherapist for radiation of a presumed malignant spinal process. RESULT: For differential diagnosis a magnetic resonance imaging (MRI) of the spine was performed and could lead to the correct diagnosis of an infectious spondylodiscitis. CONCLUSION: The MRI of the spine has a potential role for correct differentiation between benign and malignant spinal lesions and may thereby assist the radiotherapist in the decision making in an emergency situation.     

Inhibitory effect of lead on the proliferation of cultured vascular endothelial cells

We investigated the effect of lead nitrate (0.5, 1.0, 2.0 or 5.0 microM) on the proliferation of cultured bovine aortic endothelial cells. After exposure to lead, the number of cells and the incorporation of [3H]thymidine into the acid-insoluble fraction of the cells were reduced in parallel in a concentration-dependent manner. Histologically, lead treatment resulted in a decrease in the cell number accompanied by a change in the cell shape from polygonal to spindle; however, no degenerative change was observed except in 5.0 microM lead-treated cells. Furthermore, stimulation of [3H]thymidine incorporation by either basic or acidic fibroblast growth factor was significantly reduced by lead. However, the leakage of lactate dehydrogenase into the medium from the cells, a marker of nonspecific cell damage, was not changed by lead. From these results, it was revealed that lead inhibits the proliferation of cultured vascular endothelial cells without nonspecific cell damage. Although lead does not destroy the monolayer of endothelial cells, the metal may exhibit its noxious effect in the repair process of the vascular endothelium.     

Development of 170 GHz/500 kW gyrotron

A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE_31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at P_RF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at P_RF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window.