Monoclonal antibodies specific for carcinoembryonic antigen and produced by two hybrid cell lines.

Spleen cells from mice immunized with purified carcinoembryonic antigen (CEA), an important tumor marker of human carcinomas, were fused with the mouse myeloma cell line P3-NSI/1-Ag4. Out of the 400 hybrids obtained, 2 secreted antibodies reacting specifically with two different antigenic determinants present on CEA molecules. They were cloned and established as permanent hybridoma cell lines. These antibodies, which have relatively high-affinities and can be produced in unlimited amounts, will be useful both for the immunochemical characterization of CEA and as a standard reagent for the identification of this antigen in human tissues and body fluids.

In vitro selection of bacteria with potential for use as probiotics in marine shrimp culture

The objective of this work was to isolate strains of lactic acid bacteria with probiotic potential from the digestive tract of marine shrimp (Litopenaeus vannamei), and to carry out in vitro selection based on multiple characters. The ideotype (ideal proposed strain) was defined by the highest averages for the traits maximum growth velocity, final count of viable cells, and inhibition halo against nine freshwater and marine pathogens, and by the lowest averages for the traits duplication time and resistance of strains to NaCl (1.5 and 3%), pH (6, 8, and 9), and biliary salts (5%). Mahalanobis distance (D²) was estimated among the evaluated strains, and the best ones were those with the shortest distances to the ideotype. Ten bacterial strains were isolated and biochemically identified as Lactobacillus plantarum (3), L. brevis (3), Weissella confusa (2), Lactococcus lactis (1), and L. delbrueckii (1). Lactobacillus plantarum strains showed a wide spectrum of action and the largest inhibition halos against pathogens, both Gram-positive and negative, high growth rate, and tolerance to all evaluated parameters. In relation to ideotype, L. plantarum showed the lowest Mahalanobis (D²) distance, followed by the strains of W. confusa, L. brevis, L. lactis, and L. delbrueckii. Among the analyzed bacterial strains, those of Lactobacillus plantarum have the greatest potential for use as a probiotic for marine shrimp.

Survival of zirconia- and metal-supported fixed dental prostheses: a systematic review

Purpose: The aim of this review was to systematically evaluate and compare the frequency of veneer chipping and core fracture of zirconia fixed dental prostheses (FOPS) and porcelain-fused-to-metal (PFM) FDPs and determine possible influencing factors. Materials and Methods: The SCOPUS database and International Association of Dental Research abstracts were searched for clinical studies involving zirconia and PFM FDPs. Furthermore, studies that were integrated into systematic reviews on PFM FDPs were also evaluated. The principle investigators of any clinical studies on zirconia FDPs were contacted to provide additional information. Based on the available information for each FOP, a data file was constructed. Veneer chipping was divided into three grades (grade 1 = polishing, grade 2 = repair, grade 3 = replacement). To assess the frequency of veneer chipping and possible influencing factors, a piecewise exponential model was used to adjust for a study effect. Results: None of the studies on PFM FDPs (reviews and additional searching) sufficiently satisfied the criteria of this review to be included. Thirteen clinical studies on zirconia FDPs and two studies that investigated both zirconia and PFM FDPs were identified. These studies involved 664 zirconia and 134 PFM FDPs at baseline. Follow-up data were available for 595 zirconia and 127 PFM FDPs. The mean observation period was approximately 3 years for both groups. The frequency of core fracture was less than 1% in the zirconia group and 0% in the PFM group. When all studies were included, 142 veneer chippings were recorded for zirconia FDPs (24%) and 43 for PFM FDPs (34%). However, the studies differed extensively with regard to veneer chipping of zirconia: 85% of all chippings occurred in 4 studies, and 43% of all chippings included zirconia FDPs. If only studies that evaluated both types of core materials were included, the frequency of chipping was 54% for the zirconia-supported FDPs and 34% for PFM FDPs. When adjusting the survival rate for the study effect, the difference between zirconia and PFM FDPs was statistically significant for all grades of chippings (P = .001), as well as for chipping grade 3 (P = .02). If all grades of veneer chippings were taken into account, the survival of PFM FDPs was 97%, while the survival rate of the zirconia FDPs was 90% after 3 years for a typical study. For both PFM and zirconia FDPs, the frequency of grades 1 and 2 veneer chippings was considerably higher than grade 3. Veneer chipping was significantly less frequent in pressed materials than in hand-layered materials, both for zirconia and PFM FDPs (P = .04). Conclusions: Since the frequency of veneer chipping was significantly higher in the zirconia FDPs than PFM FDPs, and as refined processing procedures have started to yield better results in the laboratory, new clinical studies with these new procedures must confirm whether the frequency of veneer chipping can be reduced to the level of PFM. Int J Prosthodont 2010;23:493-502

Purification and fractionation by nanotiltration in dairy and sugar and sweetener industry applications

Nanotiltration is a membrane separation method known for its special characteristic of rejecting multivalent ions and passing monovalent ions. Thus, it is commonly applied with dilute aqueous solutions in partial salt removal, like in drinking water production. The possibilities of nanofiltration have been studied and the technique applied in a wide branch of industries, e.g. the pulp and paper, the textile and the chemical processing industry. However, most present applications and most of the potential applications studied involve dilute solutions, the permeating stream being generally water containing monovalent salts. In this study nanotiltration is investigated more as a fractionation method. A well-known application in the dairy industry is concentration and partial salt removal from whey. Concentration and partial demineralization is beneficial for futher processing of whey as whey concentrates are used e.g. in baby foods. In the experiments of this study nanotiltration effectively reduced the monovalent salts in the whey concentrate. The main concern in this application is lactose leakage into the permeate. With the nanofiltration membranes used the lactose retentions were practically ? 99%. Another dairy application studied was the purification and reuse of cleaning solutions. This is an environmentally driven application. An 80% COD reduction by nanofiltration was observed for alkaline cleaning-in-place solution. Nanofiltration is not as commonly applied in the sugar and sweeteners industry as in the dairy industry. In this study one potential application was investigated, namely xylose purification from hemicellulose hydrolyzate. Xylose is raw material for xylitol production. Xylose separation from glucose was initially studied with xylose-glucose model solutions. The ability of nanofiltration to partially separate xylose into the permeate from rather concentrated xylose-glucose solutions (10 w-% and 30 w-%) became evident. The difference in size between xylose and glucose molecules according to any size measure is small, e.g. the Stokes diameter of glucose is 0.73 nm compared to 0.65 nm for xylose. In further experiments, xylose was purified into nanoliltration permeate from a hemicellulose hydrolyzate solution. The xylose content in the total solids was increased by 1.4—1.7 fold depending on temperature, pressure and feed composition.

Tumor sensitizing function and mechanism of action of a RasGAP derived peptide

Cancer is the second cause of death after cardio-vascular diseases in economically developed countries. Two of the most commonly used anti-cancer therapies are chemo and radiotherapy. Despite the remarkable advances made in term of delivery and specificity of these two anti-tumor regimens, their toxicity towards healthy tissue remains a limitation. A promising approach to overcome this obstacle would be the utilization of therapeutic peptides that specifically augment the sensitivity of tumoral cells to treatments. Lower therapeutical doses would then be required to kill malignant cells, limiting toxic effects on healthy tissues. It was previously shown in our laboratory that the caspase-3 generated fragment N2 of RasGAP is able to potentiate the genotoxin-induced apoptosis selectively in cancer cells. In this work we show that fragment N2 strictly requires a cytoplasmic localization to deliver its pro-apoptotic effect in genotoxin-treated cancer cells. The tumor sensitizing capacity of fragment N2 was found to reside within the 10 amino acid sequence 317-326. Our laboratory earlier demonstrated that a peptide corresponding to amino acids 317 to 326 of RasGAP fused to the TAT cell permeable moiety, called TAT-RasGAP317.326, is able to sensitize cancer cells, but not normal cells, to genotoxin-induced apoptosis. In the present study we describe the capacity of TAT-RasGAP 317.326 to sensitize tumors to both chemo and radiotherapy in an in vivo mouse model. The molecular mechanism underlying the TAT-RasGAP 317.326-mediated sensitization starts now to be elucidated. We demonstrate that G3BP1, an endoribonuclease binding to amino acids 317-326 of RasGAP, is not involved in the sensitization mechanism. We also provide evidence showing that TAT-RasGAP3 17-326 potentiates the genotoxin-mediated activation of Bax in a tBid-dependent manner. Altogether our results show that TAT-RasGAP 317.326 could be potentially used in cancer therapy as sensitizer, in order to improve the efficacy of chemo and radiotherapy and prolong the life expectancy of cancer patients. Moreover, the understanding of the TAT-RasGAP317.326 mode of action might help to unravel the mechanisms by which cancer cells resist to chemo and radiotherapy and therefore to design more targeted and efficient anti-tumoral strategies.

Chemical chaperones regulate molecular chaperones in vitro and in cells under combined salt and heat stresses.

Salt and heat stresses, which are often combined in nature, induce complementing defense mechanisms. Organisms adapt to high external salinity by accumulating small organic compounds known as osmolytes, which equilibrate cellular osmotic pressure. Osmolytes can also act as "chemical chaperones" by increasing the stability of native proteins and assisting refolding of unfolded polypeptides. Adaptation to heat stress depends on the expression of heat-shock proteins, many of which are molecular chaperones, that prevent protein aggregation, disassemble protein aggregates, and assist protein refolding. We show here that Escherichia coli cells preadapted to high salinity contain increased levels of glycine betaine that prevent protein aggregation under thermal stress. After heat shock, the aggregated proteins, which escaped protection, were disaggregated in salt-adapted cells as efficiently as in low salt. Here we address the effects of four common osmolytes on chaperone activity in vitro. Systematic dose responses of glycine betaine, glycerol, proline, and trehalose revealed a regulatory effect on the folding activities of individual and combinations of chaperones GroEL, DnaK, and ClpB. With the exception of trehalose, low physiological concentrations of proline, glycerol, and especially glycine betaine activated the molecular chaperones, likely by assisting local folding in chaperone-bound polypeptides and stabilizing the native end product of the reaction. High osmolyte concentrations, especially trehalose, strongly inhibited DnaK-dependent chaperone networks, such as DnaK+GroEL and DnaK+ClpB, likely because high viscosity affects dynamic interactions between chaperones and folding substrates and stabilizes protein aggregates. Thus, during combined salt and heat stresses, cells can specifically control protein stability and chaperone-mediated disaggregation and refolding by modulating the intracellular levels of different osmolytes.

Somatic embryogenesis from zygotic embryos of Euterpe oleracea Mart.

The aim of this work was to study the morphogenetic responses of zygotic embryos of açai palm (Euterpe oleracea Mart.) submitted to several conditions of in vitro culture. Several research experiments were conducted, in laboratory, using vegetable material collected from açai palm plants at Embrapa Amazon Oriental, Belém-PA, Brazil. It was possible to verify the expression of a direct, repetitive and no-synchronized model of somatic embryogenesis in mature zygotic embryos cultivated in primary MS medium supplemented with 2,4-D (339.36 muM) and transferred to a secondary MS medium in the presence of NAA (0.537 muM) and 2iP (12.30 muM). The conversion of somatic embryos into seedlings was reached after 210 days with the transfer of the cultures to a third medium with sucrose and mineral salts concentrations reduced to a half, without growth regulators.

Estudi comparatiu dels filtres de Kalman i IMM per a navegació

Els sistemes híbrids de navegació integren mesures de posició i velocitat provinents de satèl·lits (GPS) i d’unitats de mesura inercials (IMU).Les dades d’aquests sensors s’han de fusionar i suavitzar, i per a aquest propòsit existeixen diversos algorismes de filtratge, que tracten les dades conjuntament o per separat. En aquest treball s’han codificat en Matlab els algorismes dels filtres de Kalman i IMM, i s’han comparat les seves prestacions en diverses trajectòries d’un vehicle. S’han avaluat quantitativament els errors dels dos filtres, i s’han sintonitzat els seus paràmetres per a minimitzar aquests errors. Amb una correcta sintonia dels filtres, s’ha comprovat que el filtre IMM és superior al filtre de Kalman, tant per maniobres brusques com per maniobres suaus, malgrat que la complexitat i el temps de càlcul requerit són majors.

Effect of physico-chemical conditions and operating parameters on flux and retention of different components in ultrafiltration and nanofiltration fractionation of sweet whey

Tässä väitöstutkimuksessa tutkittiin fysikaaliskemiallisten olosuhteiden ja toimintaparametrien vaikutusta juustoheran fraktiointiin. Kirjallisuusosassa on käsitelty heran ympäristövaikutusta, heran hyödyntämistä ja heran käsittelyä kalvotekniikalla. Kokeellinen osa on jaettu kahteen osaan, joista ensimmäinen käsittelee ultrasuodatusta ja toinen nanosuodatusta juustoheran fraktioinnissa. Ultrasuodatuskalvon valinta tehtiin perustuen kalvon cut-off lukuun, joka oli määritetty polyetyleeniglykoliliuoksilla olosuhteissa, joissa konsentraatiopolariosaatioei häiritse mittausta. Kriittisen vuon konseptia käytettiin sopivan proteiinikonsentraation löytämiseksi ultrasuodatuskokeisiin, koska heraproteiinit ovat tunnetusti kalvoa likaavia aineita. Ultrasuodatuskokeissa tutkittiin heran eri komponenttien suodattumista kalvon läpi ja siihen vaikuttavia ominaisuuksia. Herapermeaattien peptidifraktiot analysoitiin kokoekskluusiokromatografialla ja MALDI-TOF massaspektrometrillä. Kokeissa käytettävien nanosuodatuskalvojen keskimääräinen huokoskoko analysoitiin neutraaleilla liukoisilla aineilla ja zeta-potentiaalit virtauspotentiaalimittauksilla. Aminohappoja käytettiin malliaineina tutkittaessa huokoskoon ja varauksen merkitystä erotuksessa. Aminohappojen retentioon vaikuttivat pH ja liuoksen ionivahvuus sekä molekyylien väliset vuorovaikutukset. Heran ultrasuodatuksessa tuotettu permeaatti, joka sisälsi pieniä peptidejä, laktoosia ja suoloja, nanosuodatettiin happamassa ja emäksisessä pH:ssa. Emäksisissä oloissa tehdyssä nanosuodatuksessa foulaantumista tapahtui vähemmän ja permeaattivuo oli parempi. Emäksisissä oloissa myös selektiivisyys laktoosin erotuksessa peptideistä oli parempi verrattuna selektiivisyyteen happamissa oloissa.

Dose and time-dependent selective neurotoxicity induced by mephedrone in mice.

Mephedrone is a drug of abuse marketed as 'bath salts'. There are discrepancies concerning its long-term effects. We have investigated the neurotoxicity of mephedrone in mice following different exposition schedules. Schedule 1: four doses of 50 mg/kg. Schedule 2: four doses of 25 mg/kg. Schedule 3: three daily doses of 25 mg/kg, for two consecutive days. All schedules induced, in some animals, an aggressive behavior and hyperthermia as well as a decrease in weight gain. Mephedrone (schedule 1) induced dopaminergic and serotoninergic neurotoxicity that persisted 7 days after exposition. At a lower dose (schedule 2) only a transient dopaminergic injury was found. In the weekend consumption pattern (schedule 3), mephedrone induced dopamine and serotonin transporter loss that was accompanied by a decrease in tyrosine hydroxylase and tryptophan hydroxylase 2 expression one week after exposition. Also, mephedrone induced a depressive-like behavior, as well as a reduction in striatal D2 density, suggesting higher susceptibility to addictive drugs. In cultured cortical neurons, mephedrone induced a concentration-dependent cytotoxic effect. Using repeated doses for 2 days in an elevated ambient temperature we evidenced a loss of frontal cortex dopaminergic and hippocampal serotoninergic neuronal markers that suggest injuries at nerve endings.

In vitro organogenesis in some citrus species

In vitro organogenesis of Citrus was studied for the genotypes Citrus sinensis cv. 'Natal', C. limonia, C. volkameriana, and C. aurantium, with the use of epicotyl segments-derived explants, cultured in MT salts and vitamins medium supplemented with different concentrations of 6-benzylaminopurine (BAP - 0.0; 0.5; 1.0; 1.5 or 2.0 mg L-1). For the recalcitrant genotypes C. limonia and C. aurantium the in vitro organogenesis was also studied with internodal segments-derived explants, cultured in MT salts and vitamins medium supplemented with 0; 0.5; 1.0; 2.0, or 4.0 mg L-1 of BAP. The efficiency of culture medium supplementation with the combination of BAP (0.0; 1.0, or 2.0 mg L-1) and NAA (1-naphthaleneacetic acid - 0.0; 0.3, or 0.5 mg L-1) in the development of adventitious shoots was evaluated for C. aurantium. Culture medium supplementation with BAP is not essential for the adventitious shoots development in the four genotypes studied when epicotyl segments-derived explants are used. In general, culture media supplementation with BAP decreased the percentage of responsive explants excepted for C. sinensis cv. 'Natal' and C. limonia when the concentrations of 1.5 and 2.0 mg/L were used. The presence of cytokinin, in concentrations up to 2 mg/L, stimulated the in vitro organogenesis when internodal segments-derived explants were used for C. limonia and C. aurantium. For C. aurantium no adventitious shoots developed in explants (internodal segments) cultured in basal culture medium, without BAP supplementation. Although no statistic differences could be detected, culture media supplementation with the combination of BAP and NAA favored the development of adventitious shoots in C. aurantium. The best concentration of NAA varied according to BAP concentration. The results presented herein, show that Citrus in vitro organogenesis depends on the interaction of culture medium composition, explant differentiation level, and genotype.

Kalvojen vertailu heran nanosuodatuksessa

Työssä verrattiin kaupallisia nanosuodatuskalvoja heran konsentroinnissa. Tutkitut kalvot olivat Desal-5 DK, NF45 ja Koch SR1. NF45-kalvosta tutkittiin kahta eri sukupolven kalvoa. Konsentrointiajoja tehtiin sekä laboratoriomittakaavan levysuotimella että pilot-mittakaavan spiraalimoduulilaitteella. Lisäksi tutkittiin juoksute- ja happoheran konsentrointien eroja. Erityistä huomiota kiinnitettiin permeaattivuon arvoihin konsentroinnissa ja kalvojen suolojen ja laktoosin pidätyskykyyn. NF45-kalvon uuden sukupolven malli osoittautui mittauksissa samankaltaiseksi suolojen ja laktoosin pidätyskyvyltään kuin Desal-5 DK. Koch SR1-kalvo, jonka suolojen ja laktoosin pidätyskyky on Desal-5 DK-kalvoa heikompi, puolestaan vastaa ominaisuuksiltaan NF45 vanhan sukupolven kalvoa. Vanhan sukupolven NF45-kalvon valmistus on loppunut keväällä 2000. Vaihdettaessa vanhan sukupolven NF45-kalvot uuden sukupolven kalvoihin on odotettavissa pienemmät permeaattivuot ja suuremmat suolojen ja laktoosin retentiot kuin aiemmin NF45-kalvolla. Juoksuteheran konsentroinnissa suurimmat permeaattivuot saatiin Koch SR1-kalvolla. Levysuotimella ja spiraalimoduulilla saadaan koostumukseltaan samanlainen juoksuteheratiiviste. Levysuotimella permeaattivuot ovat samalla konsentrointikertoimella suuremmat kuin spiraalimoduulilla. Tämä johtuu spiraalimoduuliin jäävistä kuolleista alueista, joissa ei ole virtausta. Uutta prosessia suunniteltaessa voidaan käyttää laboratoriomittakaavan levysuodinkokokeita, kun halutaan tietoa saatavan tuotteen koostumuksesta. Prosessin tuotantokapasiteetin arvioimiseen tarvitaan pilot-mittakaavan spiraalimoduulikokeita. Happoheratiiviste sisältää enemmän suoloja kuin samalla kalvolla valmistettu juoksuteheratiiviste. Tämä johtuu happoheran juoksuteheraa suuremmasta suolapitoisuudesta. Lisäksi happoheran konsentroinnin permeaattivuo on pienempi kuin juoksuteheran permeaattivuo, sillä happoheran alhainen pH, noin 4,5, vaikuttaa kalvon permeabiliteettiin heikentävästi.

Dose and time-dependent selective neurotoxicity induced by mephedrone in mice.

Mephedrone is a drug of abuse marketed as 'bath salts'. There are discrepancies concerning its long-term effects. We have investigated the neurotoxicity of mephedrone in mice following different exposition schedules. Schedule 1: four doses of 50 mg/kg. Schedule 2: four doses of 25 mg/kg. Schedule 3: three daily doses of 25 mg/kg, for two consecutive days. All schedules induced, in some animals, an aggressive behavior and hyperthermia as well as a decrease in weight gain. Mephedrone (schedule 1) induced dopaminergic and serotoninergic neurotoxicity that persisted 7 days after exposition. At a lower dose (schedule 2) only a transient dopaminergic injury was found. In the weekend consumption pattern (schedule 3), mephedrone induced dopamine and serotonin transporter loss that was accompanied by a decrease in tyrosine hydroxylase and tryptophan hydroxylase 2 expression one week after exposition. Also, mephedrone induced a depressive-like behavior, as well as a reduction in striatal D2 density, suggesting higher susceptibility to addictive drugs. In cultured cortical neurons, mephedrone induced a concentration-dependent cytotoxic effect. Using repeated doses for 2 days in an elevated ambient temperature we evidenced a loss of frontal cortex dopaminergic and hippocampal serotoninergic neuronal markers that suggest injuries at nerve endings.

Sphingomonas wittichii RW1 gene reporters interrogating the dibenzofuran metabolic network highlight conditions for early successful development in contaminated microcosms.

In order to better understand the fate and activity of bacteria introduced into contaminated material for the purpose of enhancing biodegradation rates, we constructed Sphingomonas wittichii RW1 variants with gene reporters interrogating dibenzofuran metabolic activity. Three potential promoters from the dibenzofuran metabolic network were selected and fused to the gene for enhanced green fluorescent protein (EGFP). The stability of the resulting genetic constructions in RW1 was examined, with plasmids based on the broad-host range vector pME6012 being the most reliable. One of the selected promoters, upstream of the gene Swit_4925 for a putative 2-hydroxy-2,4-pentadienoate hydratase, was inducible by growth on dibenzofuran. Sphingomonas wittichii RW1 equipped with the Swit_4925 promoter egfp fusion grew in a variety of non-sterile sandy microcosms contaminated with dibenzofuran and material from a former gasification site. The strain also grew in microcosms without added dibenzofuran but to a very limited extent, and EGFP expression indicated the formation of consistent small subpopulations of cells with an active inferred dibenzofuran metabolic network. Evidence was obtained for competition for dibenzofuran metabolites scavenged by resident bacteria in the gasification site material, which resulted in a more rapid decline of the RW1 population. Our results show the importance of low inoculation densities in order to observe the population development of the introduced bacteria and further illustrate that the limited availability of unique carbon substrate may be the most important factor impinging growth.

Lacustrine Systems in Convergent Margins

From the late seventies to the present day, lacustrine sedimentology and lacustrine-related basin analysis have developed from a near-marginal aca- demic curiosity into a new ground-breaking multidisciplinary body of learning. The starting-point was economic interest in ancient lacustrine sequences as potential suppliers of natural resources such as raw materials (diatomites, clays), evaporite salts and energy (hydrocarbons and coal). The early discoveries of substantial hydrocarbon reserves connected with lacustrine facies in the western USA heralded the huge reserves found later in China, Brazil, western Africa, southeast Asia and the Caspian Sea, among other places.