An all DC-powered Josephson logic circuit

A novel DC-powered Josephson circuit is reported. An improved HUFFLE-type DC flip-flop with a parallel resistor, to prevent hang-up, is constructed by combinational circuits as well as sequential circuits. The basic device is a vertical type two-junction interferometer with only three-metal layers. The design rule is 2.5 μm. High junction-current density allows for a wide operating margin even with a low inductance load. Basic circuit function test elements have been completed. The DC flip-flop with excess gate current works as a GHz range VCO (voltage controlled oscillator) for internal clock generation. The speedup junction successfully accelerated the switching speed. The ring-oscillator showed a minimum gate delay of 11.3 ps     

Transduction of the macrophage colony-stimulating factor gene into human multidrug resistant cancer cells: enhanced therapeutic efficacy of monoclonal anti-P-glycoprotein antibody in nude mice

To develop a therapeutic modality for overcoming multidrug-resistant (MDR) cancer with anti-MDR1 antibody, we examined the effect of macrophage colony-stimulating factor (M-CSF) gene transfection into MDR AD10 cells on therapy of MDR cancer with anti-MDR1 antibody (MRK17) in nude mice. MDR human ovarian cancer (AD10) cells were transduced with the human M-CSF gene inserted into an expression vector to establish gene-modified cells capable of producing low (ML-AD10), intermediate (MM-AD10) nd high (MH-AD10) amounts of M-CSF. Systemic administration of MRK17 resulted in significant dose-dependent inhibition of subcutaneous growth of ML-AD10 tumors. In contrast, systemic administration of recombinant M-CSF in combination with MRK17 did not augment the therapeutic efficacy of MRK17 alone, but rather promoted the growth of the parent AD10 cells. To test the efficacy of in vivo M-CSF gene therapy combined with antibody, we mixed the parent AD10 cells with MH-AD10 cells producing a large amount of M-CSF, and inoculated the mixed cells subcutaneously. Treatment with MRK17 inhibited growth of the mixed cells more than that of the parent cells alone. Thus, combined therapy with anti-MDR1 mAb and M-CSF gene modification of MDR cancer cells may provide a new immunotherapeutic modality for overcoming MDR in humans.     

Increased coronary heart disease in Japanese-American men with mutation in the cholesteryl ester transfer protein gene despite increased HDL levels

Plasma high density lipoprotein (HDL) levels are strongly genetically determined and show a general inverse relationship with coronary heart disease (CHD). The cholesteryl ester transfer protein (CETP) mediates the transfer of cholesteryl esters from HDL to other lipoproteins and is a key participant in the reverse transport of cholesterol from the periphery to the liver. A high prevalence of two different CETP gene mutations (D442G, 5.1%; intron 14G:A, 0.5%), was found in 3,469 men of Japanese ancestry in the Honolulu Heart Program and mutations were associated with decreased CETP (-35%) and increased HDL chol levels (+10% for D442G). However, the overall prevalence of definite CHD was 21% in men with mutations and 16% in men without mutations. The relative risk (RR) of CHD was 1.43 in men with mutations (P < .05); after adjustment for CHD risk factors, the RR was 1.55 (P = .02); after additional adjustment for HDL levels, the RR was 1.68 (P = .008). Similar RR values were obtained for the D442G mutation alone. Increased CHD in men with mutations was primarily observed for HDL chol 41-60 mg/dl; for HDL chol > 60 mg/dl men with and without mutations had low CHD prevalence. Thus, genetic CETP deficiency appears to be an independent risk factor for CHD, primarily due to increased CHD prevalence in men with the D442G mutation and HDL cholesterol between 41 and 60 mg/dl. The findings suggest that both HDL concentration and the dynamics of cholesterol transport through HDL (i.e., reverse cholesterol transport) determine the anti-atherogenicity of the HDL fraction.     

Cloning and nucleotide sequence of the beta-D-glucosidase gene from Bifidobacterium breve clb, and expression of beta-D-glucosidase activity in Escherichia coli

Genomic DNA encoding a beta-D-glucosidase (EC 3.2.1.21), which has beta-D-fucosidase activity, was cloned from Bifidobacterium breve clb. We sequenced a 1.9-kbp cloned DNA fragment that contained a single open reading frame encoding 460 amino acids with a calculated molecular mass of 51,513 Da. A putative ribosome binding site was found 5 bp upstream of the initiation codon. The amino acid sequence of this beta-D-glucosidase from Bifidobacterium breve clb had 46% identity with that of beta-glucosidase from Microbispore bispore. The enzyme of Bifidobacterium breve clb was expressed in Escherichia coli. A cell-free extract prepared from the recombinant strain showed 80 to 90-fold more beta-D-glucosidase activity than that from Bifidobacterium breve clb. The recombinant enzyme was purified to homogeneity from cell-free extracts of the recombinant strain using 4 column chromatographies. The recovery of enzyme from the recombinant strain was about 138-fold-higher than that of Bifidobacterium breve clb. The enzymatic properties were similar to those of Bifidobacterium breve clb. For application of this recombinant enzyme, we attempted to synthesize a disaccharide that seemed to be specifically assimilated by Bifidobacteria using the condensation activity of the enzyme.     

Influence of Spin Fluctuations Upon Heat Capacity of 2D Fermi Liquid Formed on Hectorite

We measured low-temperature heat capacities of two-dimensional Fermi liquid (2D FL) formed on Hectorite down to 15mK. At a coverage where mean atomic distance is comparable to that of bulk ³ He liquid, we found that the temperature dependence deviates considerably from the expected linearity. To account for the deviation we carried through integrals including RPA spin susceptibility for the Stoner-Hubbard(SH) or the Landau's Fermi liquid (LFL) models over the effectively entire, energy-momentum space without imposing the paramagnon approximation or the like. We found numerically that the spin fluctuation develops a T ² correction at T<T* which, at T>T*, is taken over by a Tlog T term where T* is some hundredths of T _F . With these corrections we are able to interprete the data and have determined the parameters for each model consistently at the densities observed.     

Long-term survivors with pN2 non-small cell lung cancer after a complete resection with a systematic mediastinal node dissection

OBJECTIVE: To determine the distribution and significance of microcalcifications in histologic sections of the prostate. DESIGN: Retrospective review of all histologic slides of completely embedded prostates from surgical specimens. MATERIALS: Randomly selected material included 266 radical prostatectomy and 10 cystoprostatectomy prostates without prostate cancer. Nonrandomly selected specimens included 26 radical prostatectomy specimens with a Gleason pattern 5 component, 24 cases with collagenous micronodules, and 8 cases previously noted to have microcalcifications within foci of prostate cancer. RESULTS: Four patterns of microcalcifications were noted in association with prostate cancer: (1) dystrophic calcification in the comedo-type necrosis of Gleason pattern 5, (2) intraluminal calcification in cribriform-type Gleason pattern 3 prostate cancer, (3) intraluminal calcification in small acinar adenocarcinoma, and (4) stromal calcification within collagenous micronodules associated with prostate cancer. Microcalcifications were noted in 32% of prostates without cancer; 1.9% of randomly selected prostates demonstrated microcalcifications associated with prostate cancer. CONCLUSIONS: Microcalcifications are less common in association with prostate cancer than with benign prostatic ducts and acini. However, intraluminal microcalcifications associated with an atypical small glandular proliferation should not be taken as unequivocal evidence of a benign process.     

The repetitive activation of extracellular signal-regulated kinase is required for renal regeneration in rat

In this study, we investigated the activation of p42 extracellular signal-regulated kinase (ERK2) during renal regeneration after HgCl2-induced acute renal failure (ARF) in rat. ERK2 activation was observed at 5 and 29 hr after HgCl2 injection, respectively. The tyrosine phosphorylation of hepatocyte growth factor receptor (c-MET) occurred between 2.5 and 5 hr after the treatment. On the other hand, the phosphorylation of epidermal growth factor receptor (EGFR) was transiently observed at 29 hr after the injection. The peak of ornithine decarboxylase activity as a marker of G1 phase was at 10 hr, and subsequently the labeling index of proliferating cell nuclear antigen as a marker of S phase increased at 53 hr. These results indicate that the repetitive activation of ERK2 related to the phosphorylation of c-MET and EGFR is required for the renal regeneration in HgCl2-induced ARF of rat.     

Prevention of bone loss by percutaneous estradiol implants in ovariectomized rats

This study was conducted to investigate whether hydroxyapatite (HAP) is appropriate as a percutaneous drug carrier for estradiol (E2) for the suppression of bone loss. Ten-week-old female Sprague-Dawley rats were subjected either to bilateral ovariectomy (OVX) or to sham surgery (control). Ovariectomized rats were implanted percutaneously with E2-HAP disks containing low, medium or high doses of estradiol (50, 250, or 500 micrograms E2/rat, respectively). Ovariectomized rats without implant and OVX rats implanted only with HAP served as additional controls. All rats were sacrificed 90 days after surgery. At the end of the experiment, bone mineral density of the lumbar spine was measured by dual energy X-ray absorption, and serum E2 was assayed by radioimmunoassay. The bone mineral density of OVX and HAP-treated OVX rats decreased by 18% compared to sham surgery rats, but decreased by only 13, 7, and 3% in rats treated with 50, 250, and 500 micrograms E2/rat, respectively. The in vitro release of E2 from E2-HAP devices was determined by an HPLC method. Estradiol release from the HAP devices followed almost a zero-order kinetics. Estradiol remained intact in E2-HAP implants for up to six months when stored at 5, 25, and 40 degrees C. This study indicates that E2-HAP implants are effective in suppressing bone loss in the spine of OVX rats in a dose-dependent manner.     

Void fraction measurement by a gamma-ray densitometer under instantaneous pipe rupture

A high-response gamma-ray densitometer was developed for the measurement of void fraction caused by the flashing vaporization of high-pressure and -temperature water under an instantaneous pipe break accident of a boiling water reactor, BWR. The initial conditions of the water were 6.86 MPa in pressure and saturation temperature. In order to prove the reliability and accuracy, the calibration test by dropping the acrylic void simulators and the air injection test into the cold water filled in the pipe were conducted.The following results are obtained in the experiments: (1) the cone slit method is very useful to increase the measuring accuracy, (2) it is clearly observed that the apparent increase of the void fraction occurs after the rarefaction wave passes, (3) the first maximum of the void fraction occurs with some delay time after break. Secondly, the minimum void fraction concurs with the maximum pressure in the pressure recovering process.     

Production of docosahexaenoic acid by marine bacteria isolated from deep sea fish

Five bacterial strains isolated from the intestine of deep sea fish were shown to produce docosahexaenoic acid (22∶6n−3; DHA) at a level of 6.4 to 11.6% of total fatty acids when incubated in DHA-free medium. In all of the strains examined, other polyunsaturated fatty acids were barely detectable, except for eicosapentaenoic acid (20∶5n−3). A typical strain, such as T3615, produced DHA at a concentration of about 0.8 mg/L within six days of aerobic incubation at 5°C and under atmospheric pressure. The T3615 strain, belonging to the genusVibrio, is rod-shaped, Gram-negative, motile and facultatively anaerobic.