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Selected AbstractsCytotoxicity and oxidative stress caused by chemicals adsorbed on particulate matter,ENVIRONMENTAL TOXICOLOGY, Issue 5 2006Andrea Müller Abstract Air particulate matter (PM) and bound chemicals are potential mediators for adverse health effects. The cytotoxicity and changes in energy-providing processes caused by chemical compounds bound to PM of different size fractions were investigated in Tetrahymena pyriformis. The PM samplings were carried out using a high volume cascade impactor (6 size fractions between 10 ,m and less than 0.49 ,m) at three points of La Plata, Argentina: in an industrial area, a traffic-influenced urban area, and a control area. Extracts from respirable particles below 1 ,m initiated the highest cytotoxic effects, demonstrating their higher risk. In contrast, an increase on oxygen consumption was observed especially in tests of extracts from particles less than 1 ,m from urban and industrial areas. The increase on oxygen consumption could be caused by decoupling processes in the respiratory chain. Otherwise the ATP concentration was increased too, even though to a lower extent. The observed imbalance between oxygen consumption and ATP concentration in exposed T. pyriformis cells may be due to oxidative stress, caused by chemical compounds bound to the particles. Owing to the complexity of effects related to PM and their associated chemical compounds, various physiological parameters necessarily need to be investigated to obtain more information about their possible involvement in human relevant pathogenic processes. As shown here, effects on cell proliferation and on energy-providing processes are suitable indicators for the different impact of PM and adsorbed chemicals from various sampling locations. © 2006 Wiley Periodicals, Inc. Environ Toxicol 21: 457,463, 2006. [source] ATP activates both receptor and sustentacular supporting cells in the olfactory epithelium of Xenopus laevis tadpolesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2006Dirk Czesnik Abstract Nucleotides and amino acids are acknowledged categories of water-borne olfactory stimuli. In previous studies it has been shown that larvae of Xenopus laevis are able to sense amino acids. Here we report on the effect of ATP in the olfactory epithelium (OE) of Xenopus laevis tadpoles. First, ATP activates a subpopulation of cells in the OE. The ATP-sensitive subset of cells is almost perfectly disjoint from the subset of amino acid-activated cells. Both responses are not mediated by the well-described cAMP transduction pathway as the two subpopulations of cells do not overlap with a third, forskolin-activated subpopulation. We further show that, in contrast to amino acids, which act exclusively as olfactory stimuli, ATP appears to feature a second role. Surprisingly it activated a large number of sustentacular supporting cells (SCs) and, to a much lower extent, olfactory receptor neurons. The cells of the amino acid- and ATP-responding subsets featured differences in shape, size and position in the OE. The latencies to activation upon stimulus application differed markedly in these subsets. To obtain these results two technical points were important. We used a novel dextran-tetramethylrhodamine-backfilled slice preparation of the OE and we found out that an antibody to calnexin, a known molecular chaperone, also labels SCs. Our findings thus show a strong effect of ATP in the OE and we discuss some of the possible physiological functions of nucleotides in the OE. [source] Pro-VGF-derived peptides induce penile erection in male rats: possible involvement of oxytocinEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2004Salvatora Succu Abstract The effect of five peptides derived from the C-terminal portion of rat pro-VGF (VGF577-617, VGF588-617, VGF599-617, VGF556-576 and VGF588-597) on penile erection was studied after injection into the hypothalamic paraventricular nucleus of male rats. VGF577-617, VGF588-617, VGF599-617 and, to a lower extent, VGF588-597 (0.1,2 µg) induced penile erection episodes in a dose-dependent manner when injected into the paraventricular nucleus, while VGF556-576 was ineffective. VGF588-617 -induced penile erection was reduced by nitro, - l -arginine methylester (L-NAME; 20 µg), by morphine (5 µg) and by muscimol (1 µg), but not by dizocilpine [(+)MK-801; 1 µg], nor by cis -flupenthixol (10 µg) given into the paraventricular nucleus 10 min before the VGF peptide. d(CH2)5Tyr(Me)-Orn8 -vasotocin (1 µg) effectively reduced VGF588-617 -induced penile erection when given into the lateral ventricles but not when injected into the paraventricular nucleus. Immunocytochemistry with antibodies specific for the C-terminal nonapeptide sequence of pro-VGF (VGF609-617) revealed numerous neuronal fibres and terminals within the paraventricular nucleus, including its parvocellular components. Here, many immunostained neuronal terminals impinged on parvocellular oxytocinergic neurons. The present results show for the first time that certain pro-VGF C-terminus-derived peptides promote penile erection when injected into the paraventricular nucleus and suggest that, within this nucleus, these or closely related pro-VGF-derived peptides may be released to influence sexual function by activating paraventricular oxytocinergic neurons mediating penile erection. [source] Extracellular excitatory amino acids increase in the paraventricular nucleus of male rats during sexual activity: main role of N -methyl- d -aspartic acid receptors in erectile functionEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2004Maria Rosaria Melis Abstract The concentrations of glutamic and aspartic acids were measured in the dialysate obtained with vertical microdialysis probes implanted into the paraventricular nucleus of the hypothalamus of sexually potent male rats during sexual activity. Animals showed noncontact erections when put in the presence of, and copulated with, a receptive (ovarietomized oestrogen- and progesterone-primed) female rat. The concentrations of glutamic and aspartic acids in the paraventricular dialysate increased by 37 and 80%, respectively, above baseline values during exposure to the receptive female rat and by 55 and 127%, respectively, during copulation. No changes in the concentrations of glutamic and aspartic acids were detected in the paraventricular dialysate when sexually potent male rats were exposed to nonreceptive (ovariectomized not oestrogen- and progesterone-primed) female rats or when impotent male rats were used. The injection into the paraventricular nucleus of the excitatory amino acid receptor antagonist dizocilpine (5 µg), a noncompetitive N -methyl- d -aspartic acid receptor antagonist, reduced noncontact erections and significantly impaired copulatory activity. The ,-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor antagonist 6-cyano-7-nitro-quinoxaline-2,3-dione (5 µg) was also able to impair copulatory activity, but to a much lower extent than dizocilpine. In contrast, (±)-2-amino-4-phosphono-butanoic acid, a metabotropic receptor antagonist (5 µg), was found to be ineffective. These results confirm the involvement of the paraventricular nucleus in the control of erectile function and copulatory behaviour and show that excitatory amino acid concentration increases in the paraventricular nucleus when penile erection occurs in physiological contexts. [source] Degree of conversion and permeability of dental adhesivesEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2005Milena Cadenaro The aim of this study was to analyse the extent of polymerization of different adhesive films in relation to their permeability. One adhesive of each class was investigated: OptiBond FL; One-Step; Clearfil Protect Bond; and Xeno III. Adhesive films were prepared and cured with XL-2500 (3M ESPE) for 20, 40 or 60 s. Polymerization kinetic curves of the adhesives tested were obtained with differential scanning calorimetry (DSC) and data were correlated with microhardness. The permeability of the adhesives under the same experimental conditions was evaluated on human extracted teeth connected to a permeability device and analysed statistically. The results showed that the extent of polymerization obtained from DSC exotherms was directly correlated with microhardness. An increased level of polymerization after prolonged light-curing was confirmed for all adhesives. Simplified adhesives exhibited a lower extent of polymerization and showed incomplete polymerization, even after 60 s. An inverse correlation was found between the degree of cure and the permeability. This study supports the hypothesis that the permeability of simplified adhesives is correlated with incomplete polymerization of resin monomers and the extent of light exposure. These adhesives may be rendered less permeable by using longer curing times than those recommended by the respective manufacturer. [source] The nuclear DNA repair protein Ku70/80 is a tumor-associated antigen displaying rapid receptor mediated endocytosisINTERNATIONAL JOURNAL OF CANCER, Issue 10 2006Johan Fransson Abstract To be of therapeutic relevance, a tumor-associated antigen should be expressed on the surface of neoplastic cells but not, or to a significantly lower extent, on cells of non-transformed nature. The Ku heterodimer (Ku70/80) is involved in DNA double strand break recognition and repair and is ubiquitously expressed in the nucleus of all cells. However, its exclusive nuclear localization has been reassessed by studies that demonstrate Ku to be expressed on the surface of tumor cell lines, displaying functions in cell adhesion, migration and invasion. In this study, we add another feature to the pluripotent role of Ku70/80 by showing that, upon binding the novel human recombinant antibody INCA-X, the Ku70/80 heterodimer is internalized into pancreatic carcinoma cells. The receptor-mediated endocytosis of Ku70/80 is rapid (t1/2 12 min) and extensive (90% of the receptor pool inside the cell after 100 min) as measured by rotating radioimmunoassay. Ku70/80 was also successfully used as a port of entry for cytotoxic payloads to tumor cells of various origin, as determined by indirect immunotoxin administration of a saporin-conjugated, secondary anti-human antibody. Thus, the internalization properties of the Ku70/80 suggest a potential role of this tumor associated antigen in selective drug-delivery in several human malignancies. © 2006 Wiley-Liss, Inc. [source] Ethnic Stratification and Inter-Generational Differences in Japan: A Comparative Study of Korean and Japanese Status AttainmentINTERNATIONAL JOURNAL OF JAPANESE SOCIOLOGY, Issue 1 2003Myungsoo Kim Abstract: There are plenty of stereotypical discourses concerning the Korean minority in Japan that are widely accepted, not because of their plausibility, but because of the lack of basic empirical data. In order to fill this intellectual vacuum, I conducted a social stratification and mobility survey focusing on resident Korean men in 1995, comparable with the Japanese sample. The purpose of this article is exploratory rather than aimed at hypothesis testing, given the extreme paucity of the earlier empirical data for the ana-lysis of Korean minority status attainment. The results show that: 1For the Korean minority in Japan, class resources translate into educational attainment to a much lower extent than for the Japanese. 2Korean status attainment patterns deviate from those of their Japanese counterparts. For the Japanese, the crucial status attainment path is secured through educational attainment, which is not the case among Koreans. 3Despite being denied access to such mainstream status attainment paths, major status indicators for Koreans are not significantly different than those of Japanese, and regarding this equality of outcomes, one of the possible explanations is that Korean ethnic disadvantages in the status attainment process may have been overcome by mobilizing informal bilateral ethnic networks. [source] Physiological and biochemical traits involved in the genotypic variability to salt tolerance of Tunisian Cakile maritimaAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Megdiche Wided Abstract Cakile maritima (family: Brassicaceae) was collected from three provenances belonging to different bioclimatic stages (humid, semi arid and arid) in Tunisia to study their eco-physiological and biochemical responses to salinity. Seedlings were cultivated on inert sand for 20 days under NaCl treatments (0, 100, 200, 400 mm NaCl). Plant response to salinity was provenance- and salt-dependent. At 100 mm NaCl, growth parameters (leaf biomass, area, number per plant and relative growth rate) were improved in plants from Jerba (originating from arid bioclimatic stage) compared with the control, while growth was reduced in those from Tabarka (from humid area). High salt levels (400 mm NaCl) decreased the plant growth in the three provenances, but plants in Tabarka were the most salt sensitive. The relative salt tolerance of plants from Jerba and Bekalta provenances was associated with low levels of malondialdehyde as well as of electrolyte leakage and endoproteolytic activity. Salt reduced leaf hydration, the decrease in water content being dose-dependent and more pronounced in Tabarka. Increase in salinity led to significant increase in leaf succulence and decrease in leaf water potential, especially in Jerba plants. The plants from the latter displayed the highest leaf levels of Na+ and Cl,, proline, soluble carbohydrates, soluble proteins, and polyphenols. Overall, the higher salt tolerance of plants from Jerba provenance, and to a lower extent of those from Bekalta, may be partly related to their better capacity for osmotic adjustment and to limit oxidative damage when salt-challenged. Résumé Cakile maritima a été collecté (famille des Brassicaceae) dans trois provenances appartenant à des étages bioclimatiques différentes (humide, semi-aride et aride) de la Tunisie, dans le but d'étudier leurs réponses éco-physiologique et biochimique à la salinité. Des plantules ont été cultivées dans du sable inerte pendant vingt jours avec des doses croissantes de NaCl (0, 100, 200 et 400 mm NaCl). La réponse de Cakile maritima dépend de la provenance et de la salinité du milieu. A 100 mm de NaCl, les paramètres de croissance (biomasse, surface et nombre des feuilles par plante ainsi que le taux de la croissance relative) ont été améliorés chez Djerba (zone bioclimatique aride) par comparaison aux plantes témoins, tandis que la croissance a été réduite chez Tabarka (zone humide). A la plus forte dose de sel (400 mm), une réduction de la croissance des trois provenances a été enregistrée avec une nette sensibilité chez les plantes de la provenance Tabarka. La tolérance relative des deux provenances Djerba et Bekalta est associée à une faible teneur en malondialdéhyde ainsi qu'une fuite d'électrolyte et activité endo-protéolytique modérées. Le traitement salin a réduit l'hydratation des feuilles et cette diminution du contenu en eau est dose-dépendante et elle est plus prononcée chez Tabarka. En outre, l'augmentation de la salinité du milieu a entrainé une élévation de la succulence des feuilles concomitante à une diminution du potentiel hydrique notamment chez Djerba. Les plantes de cette dernière ont été les plus riches en Na+ et Cl - , en proline, carbohydrates, en protéines solubles et en polyphénols. En général, la tolérance au sel de la provenance Djerba, et à moindre degré Bekalta, est en partie reliée à la meilleure capacité d'ajustement osmotique et la limitation des dommages oxydatifs sous stress salin. [source] Noxp20 and Noxp70, two new markers of early neuronal differentiation, detected in teratocarcinoma-derived neuroectodermic precursor cellsJOURNAL OF NEUROCHEMISTRY, Issue 2 2006M. Boucquey Abstract The murine 1C11 cell line, derived from F9 pluripotent teratocarcinoma cells, exhibits features of a bipotential neuronal precursor as it converts into serotonergic or catecholaminergic neurons under appropriate induction. In order to point out molecular markers expressed in this early neuroectodermic commitment, we used a cDNA subtractive hybridization method. The 105 different isolated cDNAs represented 75 known genes, expressed sequence tags (EST) or genomic fragments. A majority of known proteins encoded by these sequences are involved in cellular mobility or migration. We characterized two sequences showing identities with ESTs and we called them Noxp20 and Noxp70. The Noxp20 transcript encodes a putative protein with a predicted caspase recruitment domain and the Noxp70 transcript encodes a putative protein displaying a Zn-finger domain. Consistent with their roles in neuronal cell development, in situ hybridization showed that Noxp20 and Noxp70 are over-expressed in brain. At embryonic days 12 and 15, Noxp20 is strongly expressed in the ventricular and intermediate zones of the brain and of the spinal cord. At embryonic day 15, Noxp70 was found to be strongly expressed in the ventricular zone around the telencephalic ventricle, and to a lower extent in the thalamus and hypothalamus. At post-natal day 10, Noxp20 mRNA was detected in the dentate gyrus, the hippocampus, the cerebellum and the olfactory bulb. [source] Activated JNK brings about accelerated apoptosis of Bcl-2-overexpressing C6 glioma cells on treatment with tamoxifenJOURNAL OF NEUROCHEMISTRY, Issue 1 2005Madhavi S. Moodbidri Abstract Tamoxifen causes apoptosis of malignant glial cells at a concentration that does not kill normal astrocytes. C6 glioma cells were stably transfected with a vector expressing Bcl-2 under the control of metallothionin promoter. Low leaky Bcl-2 expression offered complete protection against tamoxifen-induced apoptosis. High Bcl-2 levels, on the other hand, accelerated the apoptosis, with Bcl-2-overexpressing clones dying within 48 h of tamoxifen treatment as compared to 6 days for parental C6 cells. Overexpressed Bcl-2 is localized primarily in mitochondria and to a much lower extent in endoplasmic reticulum (ER). Only a minor fraction of the overexpressed Bcl-2 gets phosphorylated in tamoxifen-treated cells and the phosphorylation does not affect its binding to Bax. Tamoxifen treatment of Bcl-2-overexpressing clones was found to result in activation of c-Jun N-terminal kinase (JNK) and p38 kinase. Inhibition of JNK but not p38 kinase completely abrogated the accelerated apoptosis. Constitutively expressed endogenous c-Jun was found to be phosphorylated, resulting in increased activator protein 1 (AP-1) DNA-binding activity. Expression of Fas ligand (FasL), an AP-1 transcriptional target, increased during accelerated cell death. This presumably brought about activation of caspase 8, as inhibition of caspase 8 blocked the apoptosis. The JNK/c-Jun/AP-1/FasL pathway could be considered as a potential target for the therapy of gliomas. [source] Use of N -(N,-arylamino)maleimides to improve the thermal properties of poly(vinyl chloride) through chemical modification and graft copolymerizationJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 4 2008Abir S. Abdel-Naby The reaction of poly(vinyl chloride) (PVC) with N -(N,-arylamino)maleimide derivatives was studied. The thermal stability of the modified polymer was improved markedly when compared with that of the unmodified polymer. The stability improvement was attributed to the replacement of the labile chlorine atoms by more stable organic groups. The modified polymer also showed a lower extent of discoloration when compared with that of unmodified PVC. In order to introduce a polymeric stabilizer into PVC, the dienophilic monomer was chemically grafted onto the polymeric chains. The mechanism of the chemical modification as well as that of the graft copolymerization are discussed. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers. [source] Trigger Factor and DnaK possess overlapping substrate pools and binding specificitiesMOLECULAR MICROBIOLOGY, Issue 5 2003Elke Deuerling Summary Ribosome-associated Trigger Factor (TF) and the DnaK chaperone system assist the folding of newly synthesized proteins in Escherichia coli. Here, we show that DnaK and TF share a common substrate pool in vivo. In TF-deficient cells, ,tig, depleted for DnaK and DnaJ the amount of aggregated proteins increases with increasing temperature, amounting to 10% of total soluble protein (approximately 340 protein species) at 37°C. A similar population of proteins aggregated in DnaK depleted tig+ cells, albeit to a much lower extent. Ninety-four aggregated proteins isolated from DnaK- and DnaJ-depleted ,tig cells were identified by mass spectrometry and found to include essential cytosolic proteins. Four potential in vivo substrates were screened for chaperone binding sites using peptide libraries. Although TF and DnaK recognize different binding motifs, 77% of TF binding peptides also associated with DnaK. In the case of the nascent polypeptides TF and DnaK competed for binding, however, with competitive advantage for TF. In vivo, the loss of TF is compensated by the induction of the heat shock response and thus enhanced levels of DnaK. In summary, our results demonstrate that the co-operation of the two mechanistically distinct chaperones in protein folding is based on their overlap in substrate specificities. [source] Antigenic cross-reactivity among Porphyromonas gingivalis serotypesMOLECULAR ORAL MICROBIOLOGY, Issue 3 2000Q. Fan The goal of our research program is to develop a Porphyromonas gingivalis vaccine. Vaccine development requires identification of antigenic components shared by the many clonal types of P. gingivalis. The purpose of the present study was to evaluate the extent and nature of antigenic cross-reactivity among serotypes of P. gingivalis and to identify shared antigenic components. Strains selected to represent serotypes A,D were 33277, A7A1-28 W50 and 381, respectively. Using intact cells, antibodies were raised in rabbits. Titers were assessed by enzyme-linked immunosorbent assay (ELISA) using intact cells as antigen, Western blots were prepared and biologic activity was measured as opsonization (chemiluminescence expressed as mV) and enhancement of phagocytosis and killing by polymorphonuclear leukocytes. Extensive cross-reactivity that varied greatly among serotypes was observed by ELISA. The Western blots showed an even greater extent of cross-reactivity, with shared protein components at approximately 140, 130, 37, 32 and 28 kDa and a shared variable molecular mass smear considered to be lipopolysaccharide and other carbohydrate. Additional protein components at 110, 85, 35 and 20 kDa appeared to be shared by some but not all serotypes. In the functional assays, strains 33277 and 381 were equally well opsonized by anti-33277 and anti-381 (500,650 mV) but opsonized to a much lesser extent by anti-A7A1-28 and anti-W50 (roughly 125 mV and 350 mV respectively). A7A1-28 and W50 were opsonized by all four immune sera almost equally but to a much lower extent (roughly 400 mV and 250 mV respectively). Enhancement of phagocytosis and killing in the presence of active complement mirrored opsonization with the exception that 381 was reasonably well opsonized by anti-A7A1-28 (400 mV) and anti-W50 (350 mV), but poorly killed. The protein components at 140, 130, 37 and 28 kDa shared by all of the four serotypes appear to have potential as vaccine candidate antigens. [source] Identification of a 2,6-dichloroisonicotinic-acid-sensitive protein kinase from tobacco by affinity chromatography on benzothiadiazole-sepharose and NIM-metal chelate adsorbentPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 8 2001Christian Pillonel Abstract In the search for the target site of inducers of systemic acquired resistance (SAR), a BTH-binding protein kinase (BBPK) has been identified from tobacco by affinity chromatography on benzothiadiazole-sepharose (CGA 324041-sepharose) and NIM-metal chelate affinity resin. The substrate selectivity of the isolated enzyme (phosphorylation of histone type III-S, I,B,,IkB, S32A/S36A and NIM1) suggested a possible BBPK-mediated regulation of NIM1 in tobacco. The measurement of the effect of different SAR-inducers showed an inhibition of BBPK by 2,6-dichloroisonicotinic acid (INA) and, to a lower extent, by benzothiadiazoles and salicylic acid. Comparison between BBPK cell-free inhibition and in vivo PR-1 induction revealed that BBPK could be the target site of INA. © 2001 Society of Chemical Industry [source] Chronic immobilization-induced stress increases plasma testosterone and delays testicular maturation in pubertal ratsANDROLOGIA, Issue 1 2000S. A. Almeida Summary. We investigated whether chronic stress, applied from prepuberty to early puberty, interferes with the spermatogenic and androgenic testicular functions. Male pubertal rats (40 days old) were immobilized 6 h per day for 15 days. Plasma concentrations of corticosterone, prolactin and testosterone were significantly augmented following immobilization, whereas plasma luteinizing hormone decreased and follicle-stimulating hormone was not altered. Acute immobilization (5 min) increased prolactin and testosterone levels in control rats but caused a significantly higher increase in these hormones when superimposed on chronic stress. A lower extent of testicular maturation was observed in pubertal rats immobilized from prepuberty. [source] Review: Organotin compounds and their therapeutic potential: a report from the Organometallic Chemistry Department of the Free University of Brussels,APPLIED ORGANOMETALLIC CHEMISTRY, Issue 9 2002Marcel Gielen Abstract An overview of the development of antitumour organotin derivatives is presented and discussed for selected classes of compounds, such as tetraorganodicarboxylatodistannoxanes and related diorganotin dicarboxylates, and for triorganotin carboxylates. Among the carboxylate groups used are steroidcarboxylates and other biologically relevant carboxylates. High to very high in vitro activities have been found, sometimes equalling that of doxorubicin. Solubility in water is an important issue, dominating the in vivo testing of compounds. Polar substituents, like fluorine or polyoxaalkyl moieties, improve the water solubility. Although organotin derivatives constitute a separate class of compounds, the comparison with cisplatin is inevitable. Among the observed toxicities, neurotoxicity, known from platinum cytostatics, and gastrointestinal toxicity, typical for many oncology drugs, have been detected, but to a lower extent. Further research to develop novel useful organotin antitumour compounds needs to be carried out. Copyright © 2002 John Wiley & Sons, Ltd. [source] Induction of Metallothionein in Mesothelial Cells by ZincARTIFICIAL ORGANS, Issue 6 2007Dominik M. Alscher Abstract:, Patients on peritoneal dialysis (PD) are exposed to peritoneal dialysis fluids with unphysiological properties. Local defense systems are of importance. In this respect, metallothionein (MT) might play an important role. Because nothing is known about the achievability of MT induction in peritoneum by zinc, we performed the following study. We investigated human peritoneal mesothelial cells (HPMC) from omentum and a mesothelioma cell (MTC) line after addition of zinc in concentrations from 35 to 350 µM. Measurements of MT-mRNA and protein (by immuncytochemistry [IHC], Western blots, and dot blots) were performed. Zinc caused a clear and highly significant fourfold increase of RNA in MTC and to a lower extent in HPMC (1.6-fold, P < 0.001). IHC demonstrated a clear induction in HPMC and MTC. Western and dot blots confirmed this and showed an increase of MT from 112-mg/g total protein (TP) to 410-mg/g TP. Zinc was able to upregulate MT significantly in HPMC and MTC on the RNA and protein level. Fourfold increases of MT were achievable. [source] CFD modeling of subcooling process for beer fermentation liquidASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2009Yuejin Yuan Abstract A model of subcooling process for beer fermentation liquid was established at the base of a computational fluid dynamics (CFD) technique which assumed that all the biochemical reactions were suppressed to a lower extent by the cryogenic condition and their influences on heat and momentum transfer of liquid could be ignored. The subcooling process of fermentation liquid in a cooling tank was simulated, where the temperature was from 10 to , 1 °C. The transient temperature and velocity distributions of the fermentation liquid were obtained by the simulation. The results indicated that the temperature delamination was distinct in the direction of the tank axis, while the temperature gradient was inconspicuous along the radial direction. The fermentation liquid showed a complicated movement including numerous local small circumfluences, which was different from our conventional knowledge. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Locating the arcuate line of Douglas: Is it of surgical relevance?CLINICAL ANATOMY, Issue 1 2010P.M. Mwachaka Abstract Ventral hernia formation is a common complication of rectus abdominis musculocutaneous flap harvest. The site and extent of harvest of the flap are known contributing factors. Therefore, an accurate location of the arcuate line of Douglas, which marks the lower extent of the posterior wall of the rectus sheath, may be relevant before harvesting the flap. This study is aimed at determining the position of the arcuate line in relation to anatomical landmarks of the anterior abdominal wall. Arcuate lines were examined in 80 (44 male, 36 female) subjects, aged between 18 and 70 years, during autopsies and dissection. The position of the arcuate line was determined in relation to the umbilicus, pubic symphysis, and intersections of rectus abdominis muscle. Sixty four (80.4%) cases had the arcuate line. In most cases (52), this line was located in the upper half of a line between the umbilicus and the pubic symphysis. Most males (93%) had the arcuate line, while more than a third of females did not have it. In all these cases, the line occurred bilaterally as a single arcade, constantly at the most distal intersection of the rectus abdominis muscle. Consequently, the arcuate line is most reliably marked superficially by the distal tendinous intersection of the rectus abdominis muscle. Harvesting of the muscle cranial to this point will minimize defects in the anterior abdominal wall that may lead to hernia formation. Clin. Anat. 23:84,86, 2010. © 2009 Wiley-Liss, Inc. [source] Weathering the escarpment: chemical and physical rates and processes, south-eastern AustraliaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2009Benjamin C. Burke Abstract Differences in chemical weathering extent and character are expected to exist across topographic escarpments due to spatial gradients of climatic and/or tectonic forcing. The passive margin escarpment of south-eastern Australia has a debated but generally accepted model of propagation in which it retreated (within 40 Ma) to near its current position following rifting between Australia and New Zealand 85,100 Ma before present. We focus on this escarpment to quantify chemical weathering rates and processes and how they may provide insight into scarp evolution and retreat. We compare chemical weathering extents and rates above and below the escarpment using a mass balance approach coupling major and trace element analyses with previous measurements of denudation rates using cosmogenic nuclides (10Be and 26Al). We find a slight gradient in saprolite chemical weathering rate as a percentage of total weathering rate across the escarpment. The lowlands area, encompassing the region extending from the base of the escarpment to the coast, experiences a greater extent of chemical weathering than the highland region above the escarpment. Percents of denudation attributable to saprolite weathering average 57 ± 6% and 47 ± 7% at low and high sites respectively. Furthermore, the chemical index of alteration (CIA), a ratio of immobile to mobile oxides in granitic material that increases with weathering extent, have corresponding average values of 73·7 ± 3·9 and 65·5 ± 3·4, indicating lower extents of weathering above the escarpment. Finally, we quantify variations in the rates and extent of chemical weathering at the hillslope scale across the escarpment to suggest new insight into how climate differences and hillslope topography help drive landscape evolution, potentially overprinting longer term tectonic forcing. Copyright © 2009 John Wiley & Sons, Ltd. [source] Cooperative and Competitive Binding in Synergistic Mixtures of Thermobifida fuscaCellulases Cel5A, Cel6B, and Cel9ABIOTECHNOLOGY PROGRESS, Issue 4 2002Tina Jeoh Synergism between cellulases facilitates efficient hydrolysis of microcrystalline cellulose. We hypothesize that the effects of synergism, observed as enhanced extents of hydrolysis, are related to cellulase binding to the substrate in mixtures. In this study, direct measurements of bound concentrations of fluorescence-labeled T. fuscaCel5A, Cel6B, and Cel9A on bacterial microcrystalline cellulose were used to study binding behaviors of cellulases in binary component reactions. The accuracy of the determination of fluorescence-labeled cellulase concentrations in binary component mixtures was in the range of 7,9%. Data at 5 °C show that binding levels of cellulases in mixture reactions are only 22,70% of the binding levels in single component reactions. At 50 °C, however, most of the cellulase components in the same mixtures bound to extents of 40,126% higher than in the corresponding single component reactions. The degrees of synergistic effect (DSE) observed for the reactions at 50 °C were greater than 1, indicating that the components in the mixture acted synergistically, whereas DSE < 1 was generally observed for the reactions at 5 °C indicating anti-synergistic behavior. Degrees of synergistic binding (DSB) were also calculated, where anti-synergistic mixtures had DSB < 1 and synergistic mixtures had DSB>1. We conclude that the lower extents of binding at 5 °C are due to competition for binding sites by the cellulase components in the mixtures and the enhanced binding extents at 50 °C are due to increased availability of binding sites on the substrates brought about by the higher extents of hydrolysis. [source] | |||||||||||||||||||