Construction of an expression system of insect lysozyme lacking thermal stability: the effect of selection of signal sequence on level of expression in the Pichia pastoris expression system

Expression systems of human and silkworm lysozymes were constructedusing the methylotrophic yeast Pichia pastoris as a host. Theleader sequence and its prepro peptide of     

Efficiency of Model Induction Motor Using Various Non-Oriented Electrical Steels

1. IntroductionThe total performance of inverter power supplieshas improved drastically as a result of the development of colltrol methods, higher performance in semiconductors, and higher speed, higher integration, andlower cost in integrated circuits, making it possible touse the inverter drive method in a wide range of rotating machinery which requires smaller size and/or variable speed drives. In line with these trends, magneticloss under nonsinusoidal waveform excitation, including lower …     

Low-temperature sintering of ZrW2O8–SiO2 by spark plasma sintering

Amorphous ZrW₂O₈ powder and amorphous SiO₂ powder were prepared by a sol–gel process as raw materials, and high-density ZrW₂O₈–SiO₂ were successfully prepared at a much lower temperature of 923 K for a much shorter holding time of 10 min by spark plasma sintering (SPS) method rather than by conventional melt-quenching method. The relative densities of 0.85ZrW₂O₈–0.15SiO₂ and 0.70ZrW₂O₈–0.30SiO₂ were 99.4% and 96.6%, respectively. The combined technique of a sol–gel process and SPS should enable us to prepare the varied types of high-density composites of ZrW₂O₈ without severe thermal cracking caused by melt-quenching. The thermal expansion properties and dielectric properties of ZrW₂O₈–SiO₂ were also investigated.     

Lethal effect of the expression of a killer gene SMK1 in Saccharomyces cerevisiae

Expression of the SMK1 gene which encodes the yeast killer toxinSMKT is lethal in Saccharomyces cerevisiae. Effects of deletionand site-directed mutagenesis of SMK1 on the lethality and thesecretion of the gene products were examined. Deletion of theinterstitial     

An Improved Method for the Preparation of Schardinger β-Dextrin on a Industrial Scale by Cyclodextrin Glycosyl Transferase of an Alkalophilic Bacillus Sp. (ATCC 21783)

The formation of Schardinger ß-dextrin from starch by an alkalophilic Bacillus sp. (ATCC 21783) has been studied. Factors affecting the yield of cyclodextrins include the type, concentration, and dispersion of the starch; the time of the enzymolysis, the amount of enzyme used. A method for the preparation of Schardinger ß-dextrin on a industrial scale without using precipitants was devised. The final yield of ß-cyclodextrin was 3.6 kg from 15 kg of potato starch.     

Clinically applicable bulk isolation of blood CD34+ cells for autografting in children

The quality of population-based cancer registries has been measured by the indices of the proportion of total incident cases (DCO%) registered by death certificate only (DCO), and the ratio of incidence to mortality (I/D ratio). Recently it has been recommended that DCO% should be used as an index for the reliability of diagnosing cancers and that the proportion of cases first notified via death certificate (DCN, DCN%) be used as an index for the completeness of registration. Parkin introduced a method to estimate the registration rate, the estimated proportion of the "true incidence" that are registered in population-based registries. We recommend a modified method for estimating the registration rate for cancer registries where DCN% is relatively high, as it is in Japan, as Parkin's method may overestimate the registration rate. The method is as follows: the registration rate = (1-DCN% x 1/D ratio)/(1-DCN%). The registration rates at the Osaka Cancer Registry between 1966 and 1992 were estimated using our method. During this period, the yearly registration rate was 74.6-78.4% for males and 69.1-73.3% for females. When the cancer cases were looked at according to site, the yearly registration rate was 74.2-81.6% for stomach cancer, 81.2-89.3% for lung cancer, and 71.3-76.9% for uterine cancer. These results show that the registration rate is high for cancers that have an unfavorable prognosis and low for cancers that have a favorable prognosis. We recommend that all cancer registries in Japan calculate the completeness of registration by utilizing DCN defined as the sum of DCO plus cases not reported as cancer but with supportive clinical information of such obtained through survey of the registry for DCN.     

A master-slave control system for a semi-autonomous underwater vehicle-manipulator system

Underwater vehicle-manipulator systems (UVMS) are expected to play an important role in ocean exploration. It is considered that UVMS will be operated by both automatic and manual control. We have proposed an automatic control method. In this article, we propose a master-slave system for a UVMS. The effectiveness of the proposed master-slave control system is demonstrated by using a floating underwater robot with a 2-link manipulator.     

Molecular Docking Reveals the Binding Modes of Anticancer Alkylphospholipids and Lysophosphatidylcholine within the Catalytic Domain of Cytidine Triphosphate: Phosphocholine Cytidyltransferase

Alkylphospholipids are synthetic analogues of endogenous phosphatidylcholines with a remarkable ability: induce the selective apoptosis of exponentially growing tumor cells. One hypothesis concerning their mechanism of action is the inhibition of cytidine triphosphate:phosphocholine cytidyltransferase (CCT), which would significantly suppress the phosphatidylcholine biosynthesis to trigger apoptosis. Herein, homology modeling, docking simulations, and the analyses of molecular interaction fields are used to suggest the most probable binding modes of four alkylphospholipids (edelfosine, erucylphosphocholine, perifosine, and miltefosine) and lysophosphatidylcholine at the catalytic domain of human CCT. All compounds display bind modes in agreement with the corresponding groups found in the CCT substrate, phosphocholine, while their binding strengths are increased because of the interaction of the alkyl chains with hydrophobic residues from the M domain of the protein. Analyses of the geometry of the CCT binding‐site also suggest that small groups, such as benzyl/2‐phenylethyl ethers or equivalent heterocycles, could replace the O‐methyl group in edelfosine to yield even better inhibitors. It is believed this study can guide the development of new alkylphospholipids with an improved profile for the inhibition of phosphatidylcholine biosynthesis, a critical component for cell cycle progression that can be explored in cancer chemotherapy. Practical Applications: Studies focusing on the interactions between small ligands and their protein targets are decisive for the comprehension of how conformational changes in the macromolecular structure dictates the biological activity and, consequently, how they can be explored in drug discovery. Most of the current studies on alkylphospholipids focuses on their physicochemical interactions with cholesterol and sphingolipids in lipid rafts that, because of the variability and complexity of the membrane phases, hardly can provide structural data in the X‐ray crystallography assays necessary for molecular modeling studies. Therefore, by exploring the inhibition of human cytidine triphosphate:phosphocholine cytidyltransferase as an alternative and, probably, complementary hypothesis to the membrane rafts, a helpful strategy can be provided to overcome the clinical limitations of alkylphospholipids.     

Immunohistochemical study of estrogen receptor and estradiol on papillary thyroid carcinoma in young patients

The Winnipeg Rh Laboratory has reviewed its experiences with maternal CW alloimmunization. From September 24, 1956, to March 31, 1992, 12 women with significant CW alloimmunization underwent 18 pregnancies. In 3 (4 pregnancies) the antibody, despite its strength, was 'naturally occurring' (i.e. there was no known exposure to CW-positive red cells). The remaining 9 women (14 pregnancies) had CW-positive husbands. Two had CW-negative babies and a third infant, probably CW negative, was stillborn and macerated at 43 weeks gestation. Eleven babies were CW positive and had hemolytic disease of the newborn (HDN), with antiglobulin-positive red cells. Five did not require treatment; 2 needed phototherapy only, and 4 (born between 1956 and 1963) required exchange transfusions. No anti-CW screening was carried out until 1977; thereafter it was sporadic, 11 of 51 screening red cells being CW positive in the 39-month period ending March 31st, 1992. From November 1, 1977, to March 31, 1992, 24 women (30 pregnancies, 31 conceptuses) with insignificant anti-CW alloantibodies were identified. Extrapolating these figures to the entire period from September 24, 1956, to March 31, 1992, we estimate that at least 430 women (at least 573 pregnancies) were CW alloimmunized, most of the antibodies being 'naturally occurring'. Only 2% of the conceptuses were CW positive and affected; none were severely affected. Anti-CW is relatively common, occurring in about 1 pregnant Manitoban woman in 1,100. On very rare occasions (11 times in Manitoba in 36 years and 5 months) anti-CW HDN occurs which, although not severe, may end in kernicterus with brain damage or neonatal death unless it is detected promptly and treated appropriately.