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Seventy-eight patients undergoing coronary artery bypass grafting (CABG) were compared retrospectively to evaluate whether pretreatment with coenzyme Q10 (CoQ) is effective in preventing left ventricular depression in early reperfusion following CABG. CoQ (5 mg/kg, intravenously) was given to 60 patients, 2 hours prior to the onset of cardiopulmonary bypass (CPB). CABG was performed using saphenous vein under CPB associated with cold cardioplegia in the standard fashion. Heart rate, mean arterial pressure, and cardiac index showed no significant difference between the CoQ and control groups. However, left ventricular stroke work index was significantly elevated at 6 and 10 hours of reperfusion following CABG in the CoQ-treated group compared with the controls. Serum MB-CK was lower at 0 and 6 hours of reperfusion in the CoQ group compared with the controls. These results suggest that pretreatment with intravenous CoQ is effective in preventing left ventricular depression in early reperfusion and in minimizing myocardial cellular injury during CABG followed by reperfusion.

We have isolated from B16 mouse melanoma cells a complementary DNA (Mel-18), whose deduced amino acid sequence possesses a characteristic zinc finger structure. Immunostaining with antibodies raised against partial Mel-18 peptide sequences demonstrated nuclear localization of the gene product. We have also demonstrated that this protein has DNA-binding capacity, and the zinc finger is responsible for the DNA binding. At the transcriptional level the Mel-18 mRNA was detected in all tumor cells examined as well as melanoma cells (ontogenically of neural origin) but was scarcely present in normal tissues except neural organs. The transcript is developmentally regulated. These data suggest that Mel-18 may play a role in transcriptional regulation and also in control of cell proliferation and/or neural cell development.

This report deals with a newly developed adherence-proofing method which emits a jet of air of extremely low temperature and its exposure on fresh concrete in the mixer and the agitating drum.

An acrylic clip was developed to compress the dissected aortic wall during gluing. These small instruments have a concave-convex contact face adjusted to the most common graft size. There are several advantages to this method of treatment of acute aortic dissection.

Profile measurement taken with liquid-crystal gratings and a phase-shifting technique is proposed, and its effectiveness is verified by experiment. The surface profile is obtained by measurement of the phase distributions of the sinusoidal gratings deformed by an object’s surface. The liquid-crystal grating gives an accurate phase shift, an arbitrary projection pitch, and a constant surface brightness compared with conventional gratings such as a laser interference fringe grating and a Ronchi grating. Therefore a flexible measuring system may be developed with it. Two gratings with different pitches are used to measure an object with large steps. A two-color projection system can be used to produce such gratings simultaneously. Locally varying reflectivity on a surface can also be compensated by adjustment of the color component of the projected grating with a liquid-crystal grating. Thus the contrast in the projected grating can be made uniform, and a good profile measurement can be accomplished.

An apparatus is described in which the sliding friction between a small rider and a flat surface was accomplished. Normal load was applied to the rider without mechanical contact by an electromagnetic loading system. Friction force, normal displacement of the rider and electric contact resistance could be measured simultaneously. The apparatus may be used widely to study the dynamic motion of sliding bodies under miscellaneous frictional conditions.

Friction measurements for a soft copper rider sliding on thin films of harder copper and nickel electroplated on a copper substrate were carried out at a low sliding velocity with a pin-on-flat apparatus. Examination of the dependence of friction on film thickness showed that an optimum film thickness exists at which the lowest friction coefficient is obtained without film breakdown. For smaller thicknesses than the optimum, film removal took place and a marked rise in friction occurred. An increase in friction was also observed for films thicker than the optimum thickness. This was due to large-scale plastic deformation of the softer rider resulting from a ploughing action by asperities on the thick film surface. The optimum thickness of the films was dependent on both the film material and the applied load.

The initial scratching of soft metals by relatively hard metallic asperities involves considerable plastic deformation and wear of the harder metal. Thus the penetration effect on friction is reduced successively as sliding proceeds, leading to the shearing type of friction. Such a transition state of sliding can be defined as a quasi-scratch friction process because ploughing precedes the steady sliding condition. The deformation and wear behaviour at a friction junction was investigated using model experiments between a mild steel conical rider and a flat copper surface. Changes in geometry of the rider and pile-up of the flat metal were examined metallographically and with a microscope. It was found that a stable value of the friction force is determined from the geometric shape of the junction attained after the completion of transient sliding and the effect of initial asperity shape on the friction force becomes insignificant.

The metallic friction between a hard rough and a soft smooth surface has been investigated, in which the scratching of the soft surface by the hard asperities and the transfer of soft metal to the asperities could occur. Two effects of the metal transfer on the friction were found in the frictional experiments between low carbon steel and copper surfaces. One is an increase in the shearing component of the friction resulting from the sliding between softer metals, i.e., copper and copper. A second phenomenon due to the metal transfer is an increase in the cone angle of the hard asperities which could be assumed to have conical shape, and this causes a reduction in the ploughing component. The friction force could be evaluated from the height distribution of the asperities on the rough surface and the height of front ridge formed in front of the asperities, where the two effects of the metal transfer on the friction were also taken into account.

Simplified operative technique for the long-segment atypical coarctation of the aorta was described. The main objective of this technique is to gain quick access to both thoracic and abdominal aorta with minimal blood loss, and preservation of diaphragmatic function. This procedure consists of standard thoracotomy and pararectal incision with an entry into the retroperitoneal space. Long prosthetic graft was anastomosed in an end-to-side fashion to bypass the coarctated aorta. The graft is placed through peripheral circumference of the left hemidiaphragm, where phrenic nerve injury is not likely to occur. This technique was successfully applied to two cases of long-segment atypical coarctation of the aorta due to Takayasu's aortitis. Retroperitoneal placement of the graft prevents fatal hemorrhage due to direct contact with the graft. Contamination with transintestinal exudate can also be avoided. Results of the ten-year follow-up of the similar procedure in the literature is encouraging.

Immediately after mitral commissurotomy, we measured pulmonary blood volume by dye-dilution method and investigated the relationships between pulmonary blood volume and other hemodynamic parameters. Pulmonary blood volume correlated directly to pulmonary mean transit time, cardiac index, stroke volume index, and mean left atrial pressure. Pulmonary blood volume increased with mean pulmonary arterial pressures up to 35 mm. Hg but decreased with elevation above this level. The same patterns were observed in the correlations between pulmonary blood volume and both pulmonary distending pressure and pulmonary vascular resistance. These observations suggest that the changes of the pulmonary vessels begin with the elevation of mean pulmonary arterial pressure above 35 mm. Hg, pulmonary distending pressure above 25 mm. Hg or pulmonary vascular resistance above 5 units. Therefore, it is desirable to maintain mean pulmonary arterial pressure below 35 mm. Hg in patients immediately after mitral commissurotomy.

We have analyzed the mouse melanoma antigen with monoclonal antibodies established by syngeneic immunization. To further understand the structure of this antigen at a molecular level, we have cloned the genomic DNA controlling the expression of melanoma antigen by cosmid library transfection and a monoclonal antibody. In the process of analyzing this DNA fragment we found that it contained a gene related with transformation, which was proved by tumor formation in nude mice inoculated with NIH/3T3 transfectants of this DNA fragment. We discuss the structure of the gene product based on the deduced amino acid sequence of cDNA, which maps the genome bearing transformation-related activity. J Invest Dermatol 92:284S–288S, 1989

A deformation process of flat copper surfaces scratched by diamond conical riders was observed by a metallographic technique and scanning electron microscopy. The geometric shape and the size of prows formed by material pile-up in front of the rider were examined and their influence on friction was investigated. It was found that, taking into account the actual shape of the prow, the friction force can be obtained theoretically for any cone angle.

We investigated the limitations and effectiveness of differential hybridization in the cloning of T cell-specific cDNA (complementary DNA) molecular clones. By using the technique with T cell and B cell cDNA probes, together with Northern blot analysis, we successfully isolated cDNA clones exclusively expressed in T cells from 1 X 10(4) plaque-forming units of a T cell hybridoma. These clones represent 0.068% of the mass of the cytoplasmic mRNA. Our result shows that differential hybridization is an effective procedure when used in combination with Northern blot analysis for screening of genes selectively expressed in T cells.