E-portal de cartografía de las bibliotecas de la UPC: acceso a las colecciones mediante un mapa sensible

Peer Reviewed

Hormonal protocols for in vitro production of Zebu and taurine embryos

The objective of this work was to evaluate the effects of hormonal synchronization protocols, associated or not with follicular development stimulation, on the recovery of oocytes and on in vitro production of Bos indicus and B. taurus embryos, in different seasons. Ultrasound-guided follicular aspirations (n=237) were performed without pre-treatment (G1, control group) and after follicular wave synchronization (G2), or after follicular wave synchronization and follicle growth induction (G3). Bos indicus produced more oocytes and embryos than B. taurus (18.7±0.9 vs. 11.9±0.6 oocytes and 4.8±0.3 vs. 2.1±0.2 embryos). On average, oocyte and embryo yields were higher in G3 than in G2, and both were greater than in G1, which lead to a higher conversion of oocytes to embryos in these treatments. The hot or the cold season did not affect the B. indicus outcomes, whereas, in B. taurus, both oocyte recovery and embryo production were higher in the cold season. Follicular wave synchronization improves ovum pick-up and in vitro production of embryos in both cattle subspecies evaluated.

Muurahaishapon käyttö etikkahapon ja propionihapon sovelluksissa

Työssä tutkittiin muurahais-, etikka- ja propionihapon sekä näiden johdannaisten teollisia sovelluskohteita. Työn tarkoituksena oli löytää muurahaishapolle tai sen johdannaisille potentiaalisia käyttökohteita etikka- ja propionihapon sekä näiden johdannaisten teollisista sovelluskohteista. Työssä on laaja kirjallisuuskatsaus, jossa käsitellään muurahais-, etikka- ja propionihapon kemiallisia ja fysikaalisia ominaisuuksia, ekologisia ja korroosiovaikutuksia sekä yleensä orgaanisten happojen antimikrobisia ominaisuuksia. Tämän lisäksi työssä esitellään tarkasteltavien happojen sekä happojohdannaisten markkinat teollisissa sovelluksissa Yhdysvalloissa, Länsi-Euroopassa ja Japanissa. Korvaavuuksien syventävän analyysin avulla pyrittiin löytämään ne sovelluskohteet muurahaishapolle tai sen johdannaisille, joissa ne voisivat olla hinnaltaan kilpailukykyisiä vastaavien etikka-ja propionihapposovellusten kanssa. Mahdollisen korvaavuuden rajaksi asetettiin5 000 tonnia sovelluskohdetta kohti. Kirjallisuustutkimuksen perusteella etikkahapon estereiden (asetaattiestereiden) käyttökohde liuottimien komponentteinavoisi olla potentiaalisin käyttökohde vastaaville muurahaishapon estereille (formiaattiestereille). Asetaattiestereitä on ennustettu käytettävän maailmalla 2 808 000 tonnia vuonna 2006. Niiden pääkäyttöalueet ovat liuottimina pintapäällysteissä kuten maaleissa, lakoissa sekä painomusteissa ja -väreissä. Toistaiseksi formiaattiestereitä on hyödynnetty vain muutamia satoja tonneja lähinnä lääketeollisuuden sovelluksissa välituotteena. Työssä tehtyjen alustavien laskelmien perusteella muurahaishapon esterit ovat hintatasoltaan kilpailukykyinen vaihtoehto vastaaville asetaattiestereille. Diplomityön kokeellisessa osassa etyyliformiaattia valmistettiin menestyksekkäästi laboratoriomittakaavassa. Toinen potentiaalinen uusi tuote on selluloosaformiaattikuitu (SF-kuitu). Selluloosa-asetaattikuitua käytettiin vuonna 2001 845 000 tonnia, josta 79 % kului savukefilttereiden valmistukseen. SF-kuitu on kirjallisuuden mukaan vaihtoehtoinen raaka-aine savukefilttereiden valmistukseen.

Pauson-Khand Adducts of N-Boc-propargylamine: A New Approach to 4,5-Disubstituted Cyclopentenones

A new approach to the synthesis of 4,5-disubstituted cyclopentenones is described. The strategy is based on the Pauson-Khand (PK) reaction of norbornadiene and N-Boc-propargylamine as alkyne with a masked leaving group, which can be eliminated at will. This approach to the synthesis of 4,5-disubstituted cyclopentenones overcomes the problem of using the alkylation to introduce the alpha-side-chain. As an example, prostane 13-epi-12-oxo-phytodienoic acid (13-epi-12-oxo-PDA) methyl ester was synthesized.

Germination and development of pecan cultivar seedlings by seed stratification

Abstract: The objective of this work was to evaluate the effect of seed stratification on germination rate, germination speed, and initial development of seedlings of six pecan (Carya illinoinensis) cultivars under subtropical climatic conditions in southern Brazil. For stratification, the seeds were placed in boxes with moist sand, in a cold chamber at 4°C, for 90 days. In the fourteenth week after sowing, the emergence speed index, total emergence, plant height, stem diameter, and number of leaves were evaluated. Seed stratification significantly improves the germination potential and morphological traits of the evaluated cultivars.

Regulation of Rat and Human T-cell Immune Response by Pharmacologically Modified Dendritic Cells.

BACKGROUND: The central function of dendritic cells (DC) in inducing and preventing immune responses makes them ideal therapeutic targets for the induction of immunologic tolerance. In a rat in vivo model, we showed that dexamethasone-treated DC (Dex-DC) induced indirect pathway-mediated regulation and that CD4+CD25+ T cells were involved in the observed effects. The aim of the present study was to investigate the mechanisms underlying the acquired immunoregulatory properties of Dex-DC in the rat and human experimental systems. METHODS: After treatment with dexamethasone (Dex), the immunogenicity of Dex-DC was analyzed in T-cell proliferation and two-step hyporesponsiveness induction assays. After carboxyfluorescein diacetate succinimidyl ester labeling, CD4+CD25+ regulatory T-cell expansion was analyzed by flow cytometry, and cytokine secretion was measured by ELISA. RESULTS: In this study, we demonstrate in vitro that rat Dex-DC induced selective expansion of CD4+CD25+ regulatory T cells, which were responsible for alloantigen-specific hyporesponsiveness. The induction of regulatory T-cell division by rat Dex-DC was due to secretion of interleukin (IL)-2 by DC. Similarly, in human studies, monocyte-derived Dex-DC were also poorly immunogenic, were able to induce T-cell anergy in vitro, and expand a population of T cells with regulatory functions. This was accompanied by a change in the cytokine profile in DC and T cells in favor of IL-10. CONCLUSION: These data suggest that Dex-DC induced tolerance by different mechanisms in the two systems studied. Both rat and human Dex-DC were able to induce and expand regulatory T cells, which occurred in an IL-2 dependent manner in the rat system.

Unsaturated Polyester Resins from Recycled Polyethyleneterephthalate

Tämän diplomityön tarkoituksena oli tutkia miten kuluttajien kierrättämästä polyeteenitereftalaatista ( PET ) voi valmistaa tyydyttymättömiä polyesterihartseja. Työssä valmistettiin yleiskäyttöön soveltuva laminointihartsi sekä 'gel coat' -hartsi jota käytetään esim. veneiden pintamaalina. Yleishartsin depolymerointiin käytettiin propyleeniglykolia ja 'gel coat' -hartsin valmistamiseen neopentyyliglykolia. Polykondensaatiovaiheessa reaktioon lisättiin maleiinihappoa ja lopuksi hartsit liuotettiin styreeniin. Kirjallisuusosassa esitetään eri menetelmiä PET:n depolymeroimiseksi. Lisäksi esitetään eri vaihtoehtoja glykolien, happojen, katalyyttien ja vinyylimonomeerien valitsemiseksi tyydyttymättömien polyesterihartsien valmistuksessa. Analyysimenetelmiä nestemäisten ja kovetettujen hartsien tutkimiseen ja vertailuun käydään läpi kuten myös erilaisia sovelluksia polyesterihartsien käyttämiseksi. Kokeellinen osa todisti että PET-pullojäte voidaan prosessoida hartsiksiilman uusia investointeja prosessilaitteistoon. PET:n glykolyysi kesti viidestäseitsemään tuntia ja polykondensaatiovaihe kahdesta ja puolesta viiteen tuntiin. Hartsien molekyylipainot ja mekaanisten testien tulokset olivat vertailukelpoisia kaupallisten hartsien antamien tulosten kanssa. Glykolyysivaiheen momomeeri- ja oligomeeripitoisuudet mitattiin geelipermeaatiokromatografialla, jotta nähtiin miten pitkälle depolymerisaatio oli edennyt. Tätä tietoa voidaan hyödyntää uusien hartsireseptin suunnittelussa. Polymeeriketjussa jäljellä olevien C=C kaksoissidosten määrä ja niiden isomeraatioaste maleaattimuodosta fumaraattimuotoon mitattiin 1H-NMR -menetelmällä. Tislevesien koostumus määritettiin kaasukromatografialla, ja tulokset kertoivat katalyytin sisältämän kloorin reagoineen glykolien kanssa, johtaen suureen glykolikulutukseen ja muihin ei-toivottuihin sivureaktioihin. Hartsien sietokykyä auringon valolle mitattiin niiden UV-absorption avulla. Kummastakin hartsista valmistettiin 'gel coat' -maalit jotkalaitettiin sääkoneeseen, joka simuloi auringonpaistetta ja vesisadetta vuorotellen. Näistä 'gel coateista' mitattiin niiden kellastumista. Kummastakin hartsista tehdyt valut asetettiin myös sääkoneeseen ja IR-spektreistä ennen jajälkeen koetta nähtiin että C=O ja C-O esterisidoksia oli hajonnut.

Efeito do ácido giberélico sobre a germinação de sementes de porta-enxertos cítricos

Com objetivo de avaliar o efeito do ácido giberélico sobre a germinação de sementes de porta-enxertos cítricos, um experimento foi instalado no Laboratório de Cultura de Tecidos da UFLA. Utilizou-se o delineamento de blocos casualizados, com quatro repetições. Os tratamentos foram constituídos a partir do fatorial 5 x 4 (porta-enxertos: Limoeiro-'Cravo', Tangerineira-'Sunki', Tangerineira-'Cleópatra', 'UFLAD-4' e 'UFLAD-5'; ácido giberélico: 0; 60; 120 e 180 mg L-1 ). A parcela experimental foi constituída por 25 tubos de ensaio com uma semente/tubo, empregando-se a água + ágar a 7 mg L-1 como meio de cultura, sendo usadas sementes intactas. Após a inoculação, os tubos foram armazenados em sala sob temperatura de 25 ºC e 80 % de umidade relativa, com fotoperíodo de 16 horas. O experimento foi avaliado a partir da determinação da percentagem de germinação, índice de velocidade de germinação (IVG ) e número de plântulas por semente (NPS). O limoeiro-'Cravo' apresentou maior taxa de germinação e IVG, enquanto o híbrido 'UFLAD-5' apresentou maior NPS, não havendo efeito da aplicação do ácido giberélico sobre as características avaliadas.

Avaliação da resistência à Xylella fastidiosa em germoplasma de tangerina e híbridos introduzidos da Itália e Córsega

A Clorose Variegada dos Citros (CVC), causada pela bactéria Xylella fastidiosa, é atualmente uma das doenças que mais afeta a citricultura brasileira, sendo as variedades de laranja-doce as mais afetadas. Ensaio instalado na Estação Experimental de Bebedouro (EECB), em condições de estufa, teve como objetivo avaliar o comportamento em relação à CVC de germoplasma de citros introduzidos pela EECB, Fundecitrus e Cenargen. Os materiais foram multiplicados sobre diversos porta-enxertos e, quando atingiram o tamanho adequado, inoculados por garfagem lateral de ramo doente. Cada variedade constou de quatro plantas, três das quais foram inoculadas, e a outra sem inocular deixada como padrão. As avaliações consistiram na observação de sintomas, teste de ELISA e PCR. Os primeiros sintomas nos materiais contaminados começaram a surgir 7 meses após a inoculação. Encontraram-se 18 variedades positivas no teste de PCR, o que indica sua suscetibilidade à bactéria Xylella fastidiosa. Entretanto, as variedades que foram detectadas pelo teste ELISA e não pelo PCR não foram contadas como suscetíveis e, sim, como falsos positivos.

Evaluation of a novel biomaterial in the suprachoroidal space of the rabbit eye.

PURPOSE: Drug delivery to treat diseases of the posterior segment of the eye, such as choroidal neovascularization and its complications, is hampered by poor intraocular penetration and rapid elimination of the drug from the eye. The purpose of this study was to investigate the feasibility and tolerance of suprachoroidal injections of poly(ortho ester) (POE), a bioerodible and biocompatible polymer, as a biomaterial potentially useful for development of sustained drug delivery systems. METHODS: After tunnelization of the sclera, different formulations based on POE were injected (100 microL) into the suprachoroidal space of pigmented rabbits and compared with 1% sodium hyaluronate. Follow-up consisted of fundus observations, echography, fluorescein angiography, and histologic analysis over 3 weeks. RESULTS: After injection, POE spread in the suprachoroidal space at the posterior pole. It was well tolerated and progressively disappeared from the site of injection without sequelae. No bleeding or retinal detachment occurred. Echographic pictures showed that the material was present in the suprachoroidal space for 3 weeks. Angiography revealed minor pigment irregularities at the site of injection, but no retinal edema or necrosis. Histology showed that POE was well tolerated in the choroid. CONCLUSIONS: POE suprachoroidal injections, an easy, controllable, and reproducible procedure, were well tolerated in the rabbit eye. POE appears to be a promising biomaterial to deliver drugs focally to the choroid and the retina.

A mechanism of carbapenem resistance due to a new insertion element (ISPa133) in Pseudomonas aeruginosa

This study explored the evolutionary mechanism by which the clinical isolate PA110514 yields the imipenemresistant derivative PA116136. Both isolates were examined by PFGE and SDS-PAGE, which led to the identification of a new insertion sequence, ISPa133. This element was shown to have distinct chromosomal locations in each of the original isolates that appeared to explain the differences in imipenem susceptibilty. In strain PA110514, ISPa133 is located 56 nucleotides upstream of the translational start codon, which has no effect on expression of the porin OprD. However, in strain PA116136 ISPa133 it is located in front of nucleotide 696 and, by interrupting the coding region, causes a loss of OprD expression, thus conferring imipenem resistance. In vitro experiments mimicking the natural conditions of selective pressure yielded imipenem-resistant strains in which ISPa133 similarly interrupted oprD. A mechanism is proposed whereby ISPa133 acts as a mobile switch, with its position in oprD depending on the degree of selective pressure exerted by imipenem

A mechanism of carbapenem resistance due to a new insertion element (ISPa133) in Pseudomonas aeruginosa

This study explored the evolutionary mechanism by which the clinical isolate PA110514 yields the imipenemresistant derivative PA116136. Both isolates were examined by PFGE and SDS-PAGE, which led to the identification of a new insertion sequence, ISPa133. This element was shown to have distinct chromosomal locations in each of the original isolates that appeared to explain the differences in imipenem susceptibilty. In strain PA110514, ISPa133 is located 56 nucleotides upstream of the translational start codon, which has no effect on expression of the porin OprD. However, in strain PA116136 ISPa133 it is located in front of nucleotide 696 and, by interrupting the coding region, causes a loss of OprD expression, thus conferring imipenem resistance. In vitro experiments mimicking the natural conditions of selective pressure yielded imipenem-resistant strains in which ISPa133 similarly interrupted oprD. A mechanism is proposed whereby ISPa133 acts as a mobile switch, with its position in oprD depending on the degree of selective pressure exerted by imipenem

A mechanism of carbapenem resistance due to a new insertion element (ISPa133) in Pseudomonas aeruginosa

This study explored the evolutionary mechanism by which the clinical isolate PA110514 yields the imipenemresistant derivative PA116136. Both isolates were examined by PFGE and SDS-PAGE, which led to the identification of a new insertion sequence, ISPa133. This element was shown to have distinct chromosomal locations in each of the original isolates that appeared to explain the differences in imipenem susceptibilty. In strain PA110514, ISPa133 is located 56 nucleotides upstream of the translational start codon, which has no effect on expression of the porin OprD. However, in strain PA116136 ISPa133 it is located in front of nucleotide 696 and, by interrupting the coding region, causes a loss of OprD expression, thus conferring imipenem resistance. In vitro experiments mimicking the natural conditions of selective pressure yielded imipenem-resistant strains in which ISPa133 similarly interrupted oprD. A mechanism is proposed whereby ISPa133 acts as a mobile switch, with its position in oprD depending on the degree of selective pressure exerted by imipenem

Role of seipin in lipid droplet morphology and hepatitis C virus life cycle.

Infectious hepatitis C virus (HCV) particle assembly starts at the surface of lipid droplets, cytoplasmic organelles responsible for neutral fat storage. We analysed the relationship between HCV and seipin, a protein involved in lipid droplet maturation. Although seipin overexpression did not affect the total mean volume occupied by lipid droplets nor the total triglyceride and cholesterol ester levels per cell, it caused an increase in the mean diameter of lipid droplets by 60 %, while decreasing their total number per cell. The latter two effects combined resulted in a 34 % reduction of the total outer surface area of lipid droplets per cell, with a proportional decrease in infectious viral particle production, probably due to a defect in particle assembly. These results suggest that the available outer surface of lipid droplets is a critical factor for HCV release, independent of the neutral lipid content of the cell.

A mechanism of carbapenem resistance due to a new insertion element (ISPa133) in Pseudomonas aeruginosa

This study explored the evolutionary mechanism by which the clinical isolate PA110514 yields the imipenemresistant derivative PA116136. Both isolates were examined by PFGE and SDS-PAGE, which led to the identification of a new insertion sequence, ISPa133. This element was shown to have distinct chromosomal locations in each of the original isolates that appeared to explain the differences in imipenem susceptibilty. In strain PA110514, ISPa133 is located 56 nucleotides upstream of the translational start codon, which has no effect on expression of the porin OprD. However, in strain PA116136 ISPa133 it is located in front of nucleotide 696 and, by interrupting the coding region, causes a loss of OprD expression, thus conferring imipenem resistance. In vitro experiments mimicking the natural conditions of selective pressure yielded imipenem-resistant strains in which ISPa133 similarly interrupted oprD. A mechanism is proposed whereby ISPa133 acts as a mobile switch, with its position in oprD depending on the degree of selective pressure exerted by imipenem