bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased solubility of glutathione S‐transferase‐p16 (GST‐p16) fusion protein by co‐expression of chaperones groes and groel in Escherichia coli
Authors: Luo Zhong‐Hui , Hua Zi‐Chun 
Published: July 2007

AbstractHuman cdk (cyclin dependent kinase) inhibitor p16 was fused with glutathione S‐transferase (GST) and the GST‐p16 fusion protein is under the control of T7 promoter. When expressed in E. coli BL21(DE3), most products existed in the form of insoluble inclusion bodies. When co‐expressed with molecular chaperones E. coli GroESL, most GST‐p16 products accumulated in the soluble form with a 5‐6 fold increase in solubility. When co‐produced with human protein disulfide isomerase (PDI), there was no improvement in the solubility of GST‐p16 fusion protein.
Redox regulation of signal transduction in vascular smooth muscle cells: Thiol oxidizing agents induced phospholipase D
Authors: Taher Mohiuddin M. , Mahgoub Mahmoud A. , Abd‐Elfattah Anwar S. 
Published: July 2007

AbstractDecrease in intracellular thiols leads to oxidative stress and thus may cause alterations in the activity of redox‐sensitive enzymes required for signal transduction. Here, we report that, N‐ethylmaleimide and phenylarsine oxide, which are known to oxidize free thiols as well as protein thiols, induced phosphatidyl ethanol generation in the micromolar range suggesting activation of phospholipase D in vascular smooth muscle cells. These agents also induced significant phosphatidic acid and diacylglycerol generation without causing protein kinase C activation. Phenylarsine oxide and N‐ethyl maleimide induced phosphotipase D activation is protein kinase C independent as it was not inhibited by compound‐3 and bisindolylmaleimide, potent protein kinase C inhibitors. Tyrosine kinase inhibitor herbimycin A by itself activated PLD, but inhibited the phospholipase D activation by phenytarsine oxide and N‐ethylmaleimide. These results suggest that oxidation of the cellular thiols activates phospholipase D independent of protein kinase C.
Augmentation in the expression of a ribosomal protein associated with transformation
Authors: Go Hiroki , Taniguchi ShuN′ichiro 
Published: July 2007

AbstractUsing differential hybridization technique, cDNA that was a partial sequence of rat ribosomal protein L41 was isolated from fos‐ and src‐transfected rat fibroblast 3Y1. The cDNA was named #31. Subsequently, the human counterpart(named hm3168) was cloned from a human melanoma cell line(M14) and the amino acid sequence deduced from the cDNA proved to be identical to that of HG‐12. The gene expression of hm3168 was inducible by serum‐stimulation. It reveals the possible up‐regulation of the transcription via fos‐mediated signal transduction. Northern‐blot and Western‐blot analyses showed a large expression of the #31 gene in the rat transformed cell lines.
Arachidonic acid and protein synthesis inhibitor act synergistically to suppress insulin‐stimulated glucose transport in 3T3‐L1 adipocytes
Authors: Liu David , Chen Chih‐Chiun , Chai Shin‐Pei , Ho Low‐Tone , Fong Jim C. 
Published: July 2007

AbstractThe effect of arachidonic acid (AA) on insulin‐stimulated glucose transport by 3T3‐L1 adipocytes was examined in the presence of cycloheximide. We found that AA acted synergistically with cycloheximide to suppress insulin‐stimulated glucose transport, although it alone was without effect. Similar phenomena were observed while protein synthesis inhibitors other than cycloheximide were employed. Immunoblot analysis indicated that the increase in plasma membranes of the insulin‐regulated glucose transporter (GLUT4) in response to insulin was decreased in cells pretreated with cycloheximide for a prolonged time, while total amount of GLUT4 was not altered. Simultaneous presence of AA with cycloheximide had no further effect on the amount of GLUT4 in either total or plasma membranes. Thus the present study suggests that AA in the presence of a protein synthesis inhibitor seems to decrease the intrinsic activity of GLUT4.
A multiplex RT‐PCR assay for analysis of relative transcript levels of different members of multigene families: Application to Arabidopsis calmodulin gene family
Authors: Verma Praveen K. , Upadhyaya Kailash C. 
Published: July 2007

AbstractThe high degree of conservation of nucleotide sequences among different members of a multigene family poses problems in analysis of expression patterns governed by each member of the gene family. In this report we describe a simple, semi‐quantitative and single tube multiplex RT‐PCR assay for simultaneous and relative expression analysis with an application to all the six members of Arabidopsis calmodulin multigene family. In the multiplex primer set, individual gene specific primers were derived from 3′‐untranslated region of the genes and a single common primer from the conserved exonic region. Transcriptional activation of all the members of the calmodulin gene family in response to touch was monitored. The results demonstrate that two of the genes are not regulated by touch; however, the other four that are induced by touch show a differential response including their kinetics of induction.
Inverse effects of 20K and 22K human growth hormones on the growth of T‐47D human breast cancer cells in culture and in nude mice
Authors: Fujikawa Takahiko , Kaneko Hiroshi , Hibasami Hiroshige , Sakaguchi Kesami , Alam Khorshed S. M. , Tanaka Minoru , Nakashima Kunio 
Published: July 2007

AbstractThe major form of human growth hormone (22K hGH) stimulates the growth of T‐47D human breast cancer cells in culture and in nude mice by binding to their receptors for growth hormone and prolactin. Another isoform of hGH having a smaller molecular mass (20K hGH) is known to show different binding affinities to these receptors. In this study, we have analyzed the effects of 20K hGH on the growth of T‐47D cells in vitro and in vivo. 20K hGH (50 ng/ml) inhibited the proliferation and DNA synthesis of T‐47D cells cultured in the presence and absence of 17β‐estradiol (100 ng/ml), while 22K hGH (50 ng/ml) promoted the cellular growth. In estradiol‐treated nude mice, 22K hGH (100 μg) remarkably promoted the growth of T‐47D tumor, but 20K hGH again suppressed the tumor growth significantly. The results suggest the presence of different signal pathways for these two hGH isoforms and imply a possible clinical application for 20K hGH.
Growth retardation and discordant twin pregnancy. An immunomorphological and biochemical characterisation of the human umbilical cord
Authors: Salvolini Eleonora , Lucarini Guendalina , Cester Nelvio , Arduini Domenico , Mazzanti Laura 
Published: July 2007

AbstractGrowth retardation and low birth weight represent an important factor associated with the high risk of mortality and morbidity, particularly in twin pregnancy, since twins are frequently characterised by fetal growth retardation and sometimes by a discordant growth between the twins. The present work sets out to elucidate the role of growth discordance between twins in the behaviour of human umbilical vein endothelial cells; biochemical, ultrastructural and immunohistochemical data obtained from a discordant twin pregnancy are discussed. Endothelial cells were obtained from umbilical cord of 5 singleton pregnancies and from 5 dichorionic twin pregnancies, among which was one discordant twin pregnancy. Membrane fluidity was assayed using a fluorescent probe and each sample was immunohistochemically processed employing specific monoclonal antibodies. An increased fluidity was observed in endothelial cells from the smaller twin as compared with the larger one. As concerns electron microscopy, the features of endothelial cells from the smaller twin were similar to those of twins with similar growth, while endothelial cells from the larger one were more similar to those from singleton pregnancies. Our findings confirm the presence of the feto‐fetal transfusion as a pathogenetic mechanism involved in twin growth discordancy.
Changes of glycosylation of serum proteins in psoriatic arthritis, studied by enzyme‐linked lectin assay (ELLA), using concanavalin A
Authors: Saso Luciano , Valentini Giovanni , Giardino Angela Maria , Spadaro Antonio , Riccieri Valeria , Zoppini Antonio , Silvestrini Bruno 
Published: July 2007

AbstractChanges of glycosylation of serum proteins of patients with psoriatic arthritis were detected by lectin blotting and a new enzyme‐linked lectin assay (ELLA) using concanavalin A (Con A). A good linear correlation was found between the total Con A‐reactivity of serum and the serum levels of C‐reactive protein and interleukin‐6, which is known to regulate the glycosylation pattern of proteins upon inflammation. A good linear correlation was also observed between the immunoreactivity of α1‐antitrypsin, measured by ELISA, using a monoclonal antibody sensitive to glycosylation changes, and the erythrocyte sedimentation rate and the serum concentrations of soluble interleukin‐2 receptor, an index of lymphocyte activation which correlated with some inflammatory parameters of disease activity. These protein changes, which are described here for the first time, deserve to be studied in further detail in view of their possible clinical applications.
Protein Binding in vivo to OP2 promoter of the Pseudomonas putida TOL plasmid
Authors: Miura Koshiro , Inouye Sachiye , Nakazawa Atsushi 
Published: July 2007

AbstractThe transcription of OP2 encoding enzymes for m‐toluate catabolism on the Pseudomonasputida TOL plasmid is activated by basal‐level XylS protein in the presence of m‐toluate or by overproduced XylS protein in the absence of m‐toluate. In this study, in vivo dimethyl sulfate (DMS) footprinting was performed to understand the mechanism of transcriptional regulation of OP2 promoter by XylS. In the presence of overproduced XylS without m‐toluate, several protected nucleotides were observed, indicating the binding of RNA polymerase to DNA. However, the protection was canceled upon addition of m‐toluate. These results suggest that RNA polymerase is retained by XylS on the OP2 promoter in the absence of inducer, and is released by m‐toluate binding to XylS, concomitant with transcription.
Effect of chronic alcohol ingestion on buccal mucosal expression of bFGF and Cdk2 during ulcer healing
Authors: Slomiany B. L. , Piotrowski J. , Slomiany A. 
Published: July 2007

AbstractIn this study, we investigated the effect of chronic alcohol ingestion on the interplay between the receptor‐bound basic fibroblast growth factor (bFGF‐R) and the expression of cyclin‐dependent kinase (Cdk2) in buccal mucosa during ulcer healing. Chronic ulceration was induced by a topical application of acetic acid to the buccal mucosa of rats maintained for 5 weeks on alcohol‐containing or control liquid diet. In both groups, the ulcer healing was accompanied by an increase in buccal mucosal expression of bFGF and Cdk2. In the control group, the ulcer healed within 10 days and maximum induction in bFGF (2.6‐fold) and Cdk2 (2.4‐fold) occurred by the 2nd day of healing. In contrast, the alcohol diet group showed a marked delay in ulcer healing (14 days), associated with the shift in maximum of bFGF and Cdk2 expression to the 4‐6th day, and the values were reduced by 35 to 38%. The findings show that chronic alcohol ingestion exerts detrimental effect on the signaling events initiated by bFGF‐receptor activation and propagated by Cdk2 that propels the cell cycle progression essential for rapid mucosal repair.
Hexokinase, glucose‐6‐phosphate dehydrogenase and antioxidant enzymes in diabetic reticulocytes: effects of insulin and vanadate
Authors: Gupta Bihari L. , Baquer Najma Z. 
Published: July 2007

AbstractExperimentally induced diabetic rats were treated separately with insulin and vanadate. The activities of hexokinase (HK) and glucose‐6‐phosphate dehydrogenase (G‐6PDH) were increased in reticulocyte hemolysate isolated from the diabetic rats and were restored to normal levels by insulin. The restoration was not detected in vanadate treated diabetic animals. The enzymes of glutathione metabolism namely glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione‐s‐transferase (GST) exhibited increases in their activities with diabetes and were restored to almost control values by insulin treatment. Vanadate given to diabetic animals further increased GPx, and GST. The level of superoxide dismutase(SOD) decreased in the reticulocytes of diabetic rats and catalase (CAT) was unchanged. Both CAT and SOD had normal values when the diabetic rats were treated with insulin and vanadate. It is proposed that vanadate may cause an increase in the activity of GR which may stimulate glucose transporters and glucose metabolism.
Zinc‐induced damage to carp (Cyprinus carpio L.) erythrocytes in vitro
Authors: Akahori Anna , Gabryelak Teresa , Józwiak Zofia , Gondko Roman 
Published: July 2007

AbstractFish erythrocytes were used to elucidate the effect of zinc ions on the cell antioxidant defence system. It was detected that an increase of the Zn2+ concentration (0.01‐1 mM) leads to a marked decrease (p<0.05) in the catalase and the glutathione peroxidase activities. We observed a loss of 14‐39 % activity of glutathione peroxidase, and 16‐20% diminution for catalase. No significant changes were found in case of the superoxide dismutase. Incubation of red blood cells with zinc brought about a decrease of the erythrocyte thiol group content. Treatment of carp erythrocytes with zinc ions also resulted in enhanced hemolysis and in the induction of significant (p<0.001) changes in the intracellular glucose level. The increase of glucose concentration in the erythrocytes was correlated with increased concentration of metal in the incubation medium. It was proposed that Zn could affect transport systems across the red blood cells and therefore increased the permeability of the membranes to small molecules (e.g. hexose), and led to hemolysis. Zinc ions could act as a potential cell toxicant, leading to disturbances in functions of the antioxidant defence system and to alterations in the erythrocyte membrane properties.
Expression of two dead box gene (DDX1 amd DDX6) is independent of that of MYCN in human neuroblastoma cell lines
Authors: Akiyama Kiyotaka , Akao Yukihiro , Yokoyama Masahiro , Nakagawa Yoshihito , Noguchi Tohru , Yagi Kunio , Nishi Yoshisuke 
Published: July 2007

AbstractTo examine whether two DEAD box genes, DDX1 and DDX6, would have some roles in the progression of tumors, we investigated the correlation of the expression of these genes with that of MYCN in neuroblastomas either with or without MYCN amplification. The mRNA of MYCN was observed only in the cell lines with amplification of MYCN. The mRNAs of DDX1 and DDX6 were found in all the cell lines examined, but the correlation between the mRNA levels of DDX1 or DDX6 and MYCN was poor. These findings suggest that the expression of neither DEAD box gene is correlated with the gene expression of MYCN.
Citrate carrier and lipogenic enzyme activities in lead intrate‐induced proliferative and apoptotic phase in rat liver
Authors: Dini Luciana , Giudetti Anna Maria , Ruzittu Mariateresa , Gnoni Gabriele V. , Zara Vincenzo 
Published: July 2007

AbstractAfter in vivo administration of lead nitrate, functional changes of the mitochondrial tricarboxylate carrier and of the cytosolic lipogenic enzymes acetyl‐CoA carboxylase and fatty acid synthetase have been detected in rat liver. The rate of citrate transport was greatly reduced in rats during both the proliferative phase (3 days after the lead nitrate administration) and the involutive phase (5 days after the metal injection), which follows hepatic hyperplasia and corresponds to the peak of hepatocyte apoptosis. In both phases, a decrease of the lipogenic enzyme activities has been detected. In treated animals, an alteration of mitochondrial lipid composition has also been found. The modified lipid microenvironment could be responsible for the decreased carrier activity which, in turn, may account for the reduced activities of the lipogenic enzymes.
GroEL protects the sarcoplasmic reticulum Ca ‐dependent ATPase from inactivation in vitro
Authors: Javed Masood Ul Hassan , Michelangeli Francisco , Lund Peter A. 
Published: July 2007

AbstractThe molecular chaperone, GroEL, facilitates correct protein folding and inhibits protein aggregation. The function of GroEL is often, though not invariably, dependent on the cochaperone, GroES, and ATP. In this study it is shown that GroEL alone substantially reduces the inactivation of purified Ca++‐ATPase from rabbit skeletal muscle sarcoplasmic reticulum. In the absence of GroEL, the enzyme became completely inactive in about 45‐60 hours when kept at 25°C, while in the presence of an equimolar amount of GroEL, the enzyme remained approximately 80% active even after 75 hours. Equimolar amounts of BSA or lysozyme were unable to protect the enzyme from inactivation under identical conditions. Analysis by SDS‐PAGE showed GroEL was acting by blocking the aggregation of ATPase at 25°C. GroEL was not as effective in protection at ‐20°C or 4°C. These results are discussed in the context of current models of the GroEL mechanism.
Absence of R1066X mutation in six Japanese patients with Dubin‐Johnson syndrome
Authors: Kagawa Tatehiro , Sato Masahiro , Hosoi Katsumi , Uchiyama Junzo , Nishizaki Yasuhiro , Watanabe Norihito , Inagaki Yasutaka , Kimura Minoru , Matsuzaki Shohei 
Published: July 2007

AbstractThe Dubin‐Johnson syndrome (DJS)is a rare autosomal recessive liver disease characterized by chronic conjugated hyperbilirubinemia. The phenotype of this syndrome is thought to be caused by the impaired expression of the canalicular multispecific organic anion transporter (cMOAT), which transports non‐bile salt organic anions into the bile. Recently, a mutation from arginine (Arg) to stop‐codon at codon 1066 in the cMOAT gone has been reported in one Caucasian patient with DJS. In this study, we investigated whether this mutation is found in Japanesei patients with DJS. Genomic DNAs were extracted from the leukocytes of six Japanese patients and the fragments spanning codon 1066 were amplified by polymerase‐chain reaction. The digest of the amplified fragments with a restriction enzyme, Taql, demonstrated that all of six patients did not exhibit an R1066X mutation. No mutation at Arg1066 was also confirmed by direct sequencing of the amplified products. These findings suggested that this R1066X mutation was not a major mutation in Japanese patients with DJS. Further investigation will be required in an attempt to search other mutations in cMOAT gene in Japanese patients with DJS.
Protein kinase C isoforms in the epidermal tissues of normal and postburn human skin
Authors: Wang Yen‐Chu , Hsieh Yih‐Shou , Tang Yu‐Wen , Liu Jer‐Yuh 
Published: July 2007

AbstractBecause the expression of the isoforms of protein kinase C (PKC) in human basal keratinocytes is not understood, the expression of PKC isoforms were screened in specimens of epidermal tissue from postburn skin and the normal locations for skin grafts in patients with second or higher degrees of flame injury. The expression of individual isoform was determined by Western blot technique. Only PKC α and ζ were detected in the epidermal tissues of normal and postburn skin and translocation occurred in PKC α. Patients without antibiotic treatment after flame injury had higher expressions of PKC α and ζ. These findings indicate that the mechanisms of cellular differentiation and growth in postburn epidermal tissue may be related to the expression and translocation of PKC α induced by intra‐ and extracellular stimulation. These changes in PKC α further activate the DAG/PKC signal transduction pathways.
Lipoprotein alterations, abdominal fat distribution and breast cancer
Authors: Schreier Laura E. , Berg Gabriela A. , Basilio Francisco M. , Lopez Graciela I. , Etkin Alberto E. , Wikinski Regina L. 
Published: July 2007

AbstractPlasma lipid profile and abdominal obesity have been associated with breast cancer risk, however published results have been inconsistent. To clarify these associations we studied lipid and lipoprotein alterations, obesity degree and body fat distribution, in 30 newly diagnosed breast cancer patients without treatment and 30 controls matched by age and menopausal status. Both pre and postmenopausal breast cancer patients presented higher body mass index, waist/hip ratio and insulin levels than their matched controls. An increase in triglycerides and a decrease in HDL‐cholesterol, especially in the HDL2 subfraction, were observed in patients with breast cancer. Besides, HDL particle from these patients showed increased apo A1/HDL‐cholesterol ratio. These alterations were correlated with waist/hip ratio.The association between lipoprotein alterations and abdominal obesity independent of menopausal status, in untreated newly diagnosed breast cancer patients is reported for the first time in this study.
Influence of atropine on carbachol dual effect on Ca2 mobilization in SH‐SY5Y neuroblastoma cells
Authors: Oras Aldo , Järv Jaak , Åkerman Karl E. O. 
Published: July 2007

AbstractThe muscarinic receptor stimulated mobilisation of calcium ions in SH‐SY5Y neuroblastoma cells was measured as a function on carbachol and atropine concentrations. The combined application of this pair of muscarinic agonist and antagonist yielded a set of bell‐shaped dose‐response curves. In the presence of atropine the cell responses were smaller and the up‐going phase of these relationships was shifted towards higher agonist concentration, while the down‐going phase of these curves was not influenced by the antagonist. These results pointed to a similar mechanism of the receptor inhibition at high carbachol (agonist) concentrations and by atropine (antagonist).
Inhibition of eukaryotic DNA polymerase α by persimmon (Diospyros kaki) extract and related polyphenols
Authors: Umekawa Hayato , Takada Yoshie , Furuichi Yukio , Takahashi Takao , Achiwa Yumiko , Komiya Takashi , Yoshida Shonen 
Published: July 2007

AbstractThe effects of persimmon extract (Diospyros kaki) and related polyphenols on eukaryotic DNA polymerase α were examined. It was found that persimmon extract, epigallocatechin gallate, and epicatechin gallate strongly inhibited the activity of DNA polymerase α purified from calf thymus. Among these polyphenols, persimmon extract had the most potent effect on DNA polymerase α activity and the concentration of persimmon extract producing 50% inhibition of the activity was 0.191 μM. Persimmon extract showed a weaker effect on DNA polymerase β and slightly inhibited primase and DNA polymerase I. The inhibition of DNA polymerase α by persimmon extract was competitive with the template‐primer and noncompetitive with dTTP substrate. The Ki value of DNA polymerase α for persimmon extract was estimated to be 70 nM. Moreover, persimmon extract inhibited [3H]thymidine incorporation of human peripheral lymphocyte cells stimulated by PHA.