Promyelocytic blast crisis of chronic myelogenous leukaemia with translocations (9;22) and (15;17)

The murine monoclonal antibody A7 (MAb A7) is reactive against most human gastric cancer cell lines. Using a nude mouse peritoneal dissemination model of human gastric cancer, we investigated targeted chemotherapy using a conjugate of neocarzinostatin (NCS) with MAb A7 (A7-NCS). After demonstrating cytotoxicity of the complex against the human gastric cancer cell line MKN45 in vitro, we intraperitoneally injected A7-NCS, NCS or saline into nude mice bearing peritoneally disseminated human gastric cancer. A7-NCS inhibited peritoneal dissemination significantly more effectively than NCS. MAb A7 may prove to be an effective carrier for antineoplastic drugs in patients with peritoneal dissemination of gastric cancer.     

Membrane topology of Borrelia burgdorferi and Treponema pallidum lipoproteins

A critical issue regarding the molecular architectures of Treponema pallidum and Borrelia burgdorferi, the agents of venereal syphilis and Lyme disease, respectively, concerns the membrane topologies of their major lipoprotein immunogens. A related question is whether these lipid-modified membrane proteins form intramembranous particles during freeze fracture electron microscopy. To address these issues, native borrelial and treponemal lipoproteins were reconstituted into liposomes of diverse composition. The importance of the covalently associated lipids for membrane association of lipoproteins was revealed by the observation that nonlipidated recombinant forms of both B. burgdorferi OspA and the T. pallidum 47-kDa immunogen (Tpp47) showed very weak or no binding to model bilayer vesicles. In contrast to control liposomes reconstituted with bacteriorhodopsin or bovine rhodopsin, two well-characterized transmembrane proteins, none of the lipoprotein-liposomes contained particles when examined by freeze fracture electron microscopy. To extend these findings to prokaryotic lipoproteins with relatively amphiphilic polypeptides, similar experiments were conducted with a recombinant nonlipidated form of Escherichia coli TraT, a lipoprotein which has putative transmembrane domains. The nonlipidated TraT oligomers bound vesicles derived from E. coli lipids but, surprisingly, did not form particles in the freeze-fractured liposomes. These findings support (i) a proposed topology of spirochetal lipoproteins in which the polypeptide is extrinsic to the membrane surface and (ii) the contention that particles visualized in freeze-fractured spirochetal membranes represent poorly characterized transmembrane proteins.     

Effects of deformation rate on properties of Nd,Y-codoped CaF2 transparent ceramics

Different deformation rates of Nd,Y-codoped CaF₂ transparent ceramics were prepared by ceramization of single crystals. The deformation rate effects on the crystallization behaviors, microstructures, mechanical properties, and optical performances were investigated for the first time. The results indicate that the comprehensive performances of Nd,Y-codoped CaF₂ ceramic (△a?=?62%) are the most optimal compared with other ceramics having different deformation rates (△a?=?34%, 40%, 50%, and 75%). In further investigations of the optical properties, the Nd,Y-codoped CaF₂ ceramic (△a?=?62%) sample exhibited a high transparency (T_a?>?91%, 3-mm thick,250?～?1200?nm), low light scattering, superior fracture toughness (K_1c?～?0.71?MPa·m^1/2), strong fluorescence emission, long lifetime (τ?=?348.72?μs), and broad FWHM (29.2?nm), promising a good candidate for high-power laser material.     

Designing a support for borohydride through grafting onto crosslinked polyvinylpyrrolidone

Crosslinked polyvinylpyrrolidone (PVPy) was grafted with polyvinylpyridine by irradiating the polymer beads in air from a Co⁶⁰ γ-radiation source and then heating with 4-vinylpyridine (4-VP) in water. The percentage of grafting was studied as a function of various reaction parameters and was determined from the increase in weight of PVPy and from the estimation of pyridine rings introduced into the polymer. PVPy-g-poly(4-VP) was treated with sodium in ethanol, which is known to reduce pyridine into piperidine together with small amounts of 1,2,5,6-tetrahydropyridine. On methylation with dimethyl sulfate and alkali, these are further converted into N,N-dimethylpiperidinium groups. The dimethylpiperidinium graft was used to support borohydride ions and the graft copolymer was shown to cleanly reduce several carbonyl compounds to the corresponding alcohols. © 1996 John Wiley & Sons, Inc.     

Purification, crystallisation and preliminary X-ray diffraction study of ribosome inactivating protein: saporin

OBJECTIVES: To compare transesophageal atrial pacing stress echocardiography with dobutamine stress echocardiography for feasibility, safety, duration, patient acceptance and concordance in inducing wall motion abnormalities. BACKGROUND: Transesophageal atrial pacing is an effective method of increasing heart rate and has been used in the assessment of coronary artery disease. METHODS: Both tests were performed in sequence on the same patients in random order. Transesophageal atrial pacing stress echocardiography began at a heart rate of 10 beats/min above the baseline value and was increased by 20 beats/min every two min until 85% of the age-predicted maximum heart rate or another end point was reached. Dobutamine echocardiography was performed using three-min stages and a maximum dose of 40 microg/kg per min. Atropine (total dose < or =2 mg) was administered at the start of the 40 microg/kg per min stage if needed to augment heart rate or during pacing if Wenckebach heart block occurred. RESULTS: Transesophageal atrial pacing stress echocardiography was feasible in 100 of 104 patients (96%); the duration (8.6+/-3.6 min) was significantly shorter than that of dobutamine stress echocardiography (15.1+/-3.9 min) (p = 0.0001). With transesophageal atrial pacing stress echocardiography, the recovery period was shorter, symptoms and dysrhythmias were fewer, hypertension and hypotension were less common and target heart rate was more frequently achieved. No complications occurred with either test. Patient acceptance was satisfactory. Agreement between results of both tests was good for segmental wall motion scoring with a 16-segment model, scores 1 to 5 (kappa: rest, 0.79; peak, 0.57) and test interpretation (normal, ischemia, infarction or resting wall motion abnormality with ischemia) (kappa: 0.77). CONCLUSIONS: Transesophageal atrial pacing stress echocardiography is a feasible, well-tolerated alternative to dobutamine stress echocardiography. It can be performed rapidly and shows good agreement with dobutamine stress echocardiography in the induction of myocardial ischemia.     

High-gain, V-band, low-noise MMIC amplifiers usingpseudomorphic MODFETs

State-of-the-art, 60-GHz, low-noise MMICs based on pseudomorphic modulation-doped FETs, with 0.25-μm×60-μm gates offset 0.3 μm from the source ohmic, are discussed. Single-state low-noise amplifiers (LNAs) exhibited minimum noise figures of 2.90 dB with 4.1 dB of associated gain at 59.25 GHz. Dual-state MMICs had minimum noise figures of 3.5 dB and 10.8 dB of associated gain at 58.50 GHz. Cascaded four-stage LNAs (two dual-stage MMICs) had minimum noise figures of 3.7 dB and over 20.7 dB of associated gain at 58.0 GHz. Finally, when biased for maximum gain, the four-stage amplifier exhibited over 30.4 dB of gain at 60.0 GHz