The shortage of human tissues and organs for allotransplantation can be overcome by xenotransplantation. As a source of organs, the miniature pig is convenient. However, the presence of pathogens transmissible to the recipients, especially porcine endogenous retrovirus (PERV), represents a threat for successfull xenotransplantation. Infectious PERVs contain three classes of envelope glycoprotein. Two classes, PERV-A and PERV-B are polytropic, they can infect human, pig and mink cells in vitro. PERV-C is evolutionary young, ecotropic isolate that can infect pig only. We previously detected a new full-lenght, but replication-defective PERV-A isolate dubbed (MAMBA) with high transcriptional activity in Large-White pig from a Czech breed. To support our results with PERV-MAMBA epigenetic regulation in pig tissues, in vitro DNA methylation essay was accomplished. Methylated or non-methylated reporter plasmids containing provirus 5' LTR were transfected into 293T cells and luciferase activity was measured. In both cases, methylated LTR decreased significantly expression of luciferase. Thus, PERV LTR-driven transcription is sensitive to DNA methylation. We also used PERV-A MAMBA provirus to study recombination between two pig endogenous retroviruses. We prepared 293T and BeWo cell clones harboring PERV-A...

8 ABSTRACT Historically pig is allocated to a group of animals which use certain parts of their small intestine to acquire a fully developed primary B cell reperoire. Development of such primary repertoire is independent on the antigen presence and resembles the primary lymphopoietic activity of avian bursa of Fabricius. However, some findings concernig the pig's alignment in the above mentioned group suggest otherwise. This graduation thesis is focused on the investigtion of lymphocyte populations and subpopulations in the small intestine of germ-free and conventional piglets. The aim is to determine whether the percentage amounts of lymphocyte populations is dependent on the intestinal colonization. Using Flow Cytometry the significant differences between individual samples were assesed allowing us to conclude which parts of the small intestine could possibly be used for the development of B cell repertoire. Moreover, the status of isotype switching of B lymphocytes isolated from different intestinal parts was determined by the means of PCR analysis. Our data suggest that the small intestine colonization has a crucial role in development of all the main lymphocyte populations as well as some of their subpopulations. The greatest influence of colonization was observed concerning B lymphocytes and their...

On estime qu'approximativement 20 millions de personnes dans le monde souffrent d'insuffisance cardiaque et la prévalence de cette pathologie ne cesse d'augmenter avec le vieillissement croissant de la population. L'évaluation de la fonction ventriculaire gauche par la mesure de la fraction d'éjection permet en fait de distinguer deux populations distinctes de patients insuffisants cardiaques : l'une avec et l'autre sans altération de la fraction d'éjection, encore dénommées respectivement Heart Failure with Reduced Ejection Fraction (IC-FEr) et Heart Failure with Preserved Ejection Fraction (IC-FEp). On ne sait pas aujourd'hui si ces deux entités représentent deux pathologies distinctes ou, au contraire, deux entités intimement liées. L'IC-FEp est actuellement observée chez environ 40 à 50% des patients présentant une insuffisance cardiaque et son évolution est semblable à celle des patients IC-FEr.Le concept d'IC-FEp soulève toutefois des difficultés conceptuelles : d'une part car la notion d'une fraction d'éjection préservée implique la connaissance de sa valeur de base et d'autre part, les valeurs dites "normales" de la fraction d'éjection sont encore à établir. Par ailleurs, la vision mécanique du cœur comme une pompe hémodynamique ou musculaire conditionne la compréhension de la physiopathologie de la IF-FEp.Dans ce contexte, nous avons mis au point un modèle porcin de dysfonction diastolique avec éjection préservée secondaire à une hypertension artérielle induite par une perfusion continue d'angiotensine II pendant 28 jours. Dans ces conditions, nous avons démontré une altération de la fonction ventriculaire gauche alors même que l'éjection était préservée. Ceci était objectivé par 1) une augmentation paradoxale des durées relatives de contraction et de relaxation isovolumiques, 2) des réponses inappropriées des phases isovolumiques du cycle cardiaque à des augmentations de la fréquence et de l'inotropisme cardiaques et 3) une étroite relation entre ces deux phases isovolumiques (couplage contraction-relaxation). L'inadéquation entre les niveaux de fréquence cardiaque et des phases isovolumiques nous a amené à évaluer les effets de la modulation pharmacologique de la fréquence cardiaque sur le couplage contraction-relaxation. Ainsi la réduction sélective de la fréquence cardiaque par l'administration d'ivabradine, un inhibiteur des canaux If, a réduit significativement la durée de ces deux phases et favorisé le remplissage. Cependant, cette normalisation n'était qu'apparente puisque le ratio entre la contraction et la relaxation isovolumiques restait augmenté à J28, en défaveur de la contraction isovolumique.En conclusion, le développement d'une dysfonction diastolique avec une éjection préservée s'accompagne d'une dysfonction systolique qui entrave une réponse adéquate du myocarde à un stress dans un contexte d'hypertension chronique. / Approximately 20 millions individuals in the world experience heart failure symptoms; heart failure prevalence is continuously rising with population aging. Left ventricular function evaluation by the ejection fraction allows distinguishing two different patient sets: one with and one other without ejection fraction alteration, respectively named Heart Failure with Reduced Ejection Fraction (HF-rEF) and Heart Failure with Preserved Ejection Fraction (HF-pEF). It is unknown if these two clinical presentations represent two different pathologies or two manifestations of the same clinical entity. HF-pEF is found in about 40-50% of patients with heart failure and its evolution is similar to that of patients with HF-rEF.However, several conceptual difficulties deal with the HFpEF: on one hand, talking about preserved ejection fraction implies the knowledge of its basal value; on the other, the normality needs to be established. Moreover, considering the heart either as a hemodynamic pump or as a muscular pump may modify the understanding of HFpEF physiopathology.We therefore set up a swine model of diastolic dysfunction with preserved ejection induced by chronic hypertension, which was obtained by continuous perfusion of angiotensin II during 28 days. In these conditions, we clearly demonstrated a LV function impairment, while the ejection phase parameters remained preserved. The LV impairment is demonstrated by: 1) the paradox increase of the relative durations of isovolumic contraction and relaxation; 2) the blunted responses of the isovolumic phases of cardiac cycle to heart rate augmentation and cardiac inotropisme; 3) a straight relationship between these two isovolumic phases (contraction-relaxation relationship).The mismatch between the heart rate and the isovolumic phases behaviour led us to investigate the possible effects of the heart rate pharmacological modulation on the contraction-relaxation coupling. The selective reduction of the heart rate by ivabradine administration (a selective If channel inhibitor) was able to significantly reduce the isovolumic contraction and relaxation phases' durations, thus improving filling phase dynamics. Anyway, this “normalisation” was only apparent, because the contraction to relaxation ratio was increased at day 28, to the detriment of the isovolumic contraction.In conclusion, chronic hypertension induces a diastolic dysfunction with a preserved ejection fraction paralleled by a systolic dysfunction which is responsible of a blunted myocardial response to stress.

L’optimisation de l’utilisation de phosphore reste un enjeu majeur pour assurer la durabilité de nos filières avicoles et porcines. Aujourd’hui, l’utilisation de coproduits, relativement riches en fibres alimentaires, est grandissante. Or, les fibres alimentaires sont reconnues pour moduler les processus de digestion et la digestibilité des nutriments. Ce travail de thèse a permis de progresser sur les mécanismes digestifs engendrés par l’apport de coproduits riches en fibres alimentaires et leurs effets sur la digestion des minéraux, en lien avec la phytase microbienne, spécifiquement chez le porc et le poulet. Leurs conséquences métaboliques en terme de balance minérale et d’équilibre acidobasique ont également été mises en évidence Les connaissances acquises vont contribuer à l’amélioration de l’apport en minéraux, notamment de phosphore et de calcium, dans des formules diversifiées chez le porc et le poulet. A terme, ceci permettra de mieux adapter nos systèmes d’alimentations au regard des enjeux de durabilité. / The optimisation of the use of phosphorus remains a major challenge to ensure the sustainability of poultry and pig industry. Today, the use of co-product, relatively rich in dietary fibre, is increasing. However, dietary fibre is known to modulate digestion processes and digestibility of nutrients. This work contributed to progress on the digestive mechanisms generated by the intake of dietary fibre from coproducts and their effects on the digestion of minerals, in relation with microbial phytase, specifically in pigs and chickens. Their metabolic consequences in terms of mineral and acid-base balance have also been demonstrated. The knowledge gained will contribute to the improvement of the intake of minerals, in particular phosphorus and calcium, in diversified formulas in pigs and the chicken. Finally, this will allow us to better adapt our feeding systems to the challenges of sustainability.

O nervo vestíbulo-coclear da cobaia possui peculiaridades não encontradas em outros nervos periféricos. Não foram encontradas informações detalhadas sobre os aspectos morfométricos do VIII nervo craniano em cobaias adultas na literatura. A avaliação descritiva e quantitativa no presente estudo, evidencia informações que precedem o estudo das alterações que ocorrem em modelos experimentais de neuropatias do VIII nervo craniano e as doenças ou lesões que possam afetar o homem. Foram utilizadas 8 cobaias adultas, perfundidas com glutaraldeído a 2,5% em tampão cacodilato de sódio (0,025 M). Seus nervos direito e esquerdo (n=6, 4 nervos direito e 2 esquerdos) foram dissecados na região mediana do nervo e pós fixado com tetróxido de ósmio (OsO4) a 1% e incluídos em resina epóxi Poly/Bed 812®. Os fragmentos foram cortados em secções transversais semifinas seriadas (6 nervos) com uma espessura de 0,5 μm e corados com azul de toluidina para a microscopia de luz. Foram analisados os aspectos histológicos descritivos e topográficos do nervo vestíbulo-coclear em cobaias adultas, bem como os aspectos histométricos na parte mediana do nervo, no referente a densidade de fibras mielínicas, a distribuição dos diâmetros de tal tipo de fibras mielínicas, ao cálculo da razão G e o número de vasos sangüíneos encontrados dentro da área de cada nervo. O nervo coclear é envolvido pelo vestibular na porção inicial da junção de ambos. O conjunto, nervos coclear e vestibular e nervo vestíbulo-coclear têm a aparência bifurcada da letra Y, na horizontal com os ramos lateralizados, possuindo em média 5 mm de comprimento. É ricamente vascularizado e documenta uma completa interposição das fibras dos nervos coclear e vestibular, quando o fascículo do VIII nervo está completamente constituído. As suas fibras mielínicas dispõem-se paralelamente em seu sentido longitudinal e são circundadas por escasso tecido endoneural. Não foram evidencias fibras amielínicas no VIII nervo. A distribuição das fibras mielínicas no segmento mediano do VIII nervo craniano foi unimodal, havendo predomínio de fibras com 3,5 m de diâmetro. O número de fibras foi de 5.390 ± 1.504 fibras. O diâmetro das fibras variou de 1,5 a 6 m de diâmetro. Os axônios com 2,5 m de diâmetro foram predominantes quantitativamente: 6.757 ± 1.922 axônios. O diâmetro axonal variou entre 1 a 4,5 m. A densidade média das fibras do VIII nervo em seu segmento mediano foi de 41.474 ± 4384 fibras/mm2. O diâmetro fascicular foi de 0,77 ± 0,04 mm. A razão G varia de 0,2 a 0,9. O maior número de fibras tem razão G de 0,7 e 0,6, respectivamente, predominando as fibras com 0,7. Os resultados descritos neste trabalho científico são originais, contendo alguns resultados inéditos e pouco estudados na literatura científica sobre a anatomia e morfometria do VIII nervo craniano em cobaia. O nervo vestíbulo-coclear da cobaia é um nervo sensitivo aferente especial, e bem diferente em sua anátomo-fisiologia de todos os outros nervos sensitivos e motores encontrados nos mamíferos. A cobaia adulta é um excelente modelo experimental para o estudo do nervo vestíbulo-coclear, semelhantes aos de humanos. / The vestibulocochlear (VIIIth cranial nerve) nerve of guinea pigs have special features not common for peripheral nerves in general. There are no detailed reports on the morphometric characteristics of the VIII nerve in adult guinea pigs. This is a descriptive and qualitative study that shows normal parameters that are useful in experimental models of the VIIIth nerve neuropathy. Eight adult guinea pigs were perfused with 2.5% glutaraldehyde in isotonic cacodilate buffer (0.025M). The right (N=4) and left (N=2) nerves were dissected in the median region, post-fixed in 1% osmuin tetroxide and embedded in epoxy resin. Semithin (0.5 µm) serial transverse sections were stained with 1% toluidine blue for light microscopy study. The descriptive histology and the topographical and histometric aspects of the median region of the nerve were analyzed, including myelinated fiber density, myelinated fiber diameter distribution, g ratio and number of endoneural capillary vessels. The cochlear nerve is enveloped by the vestibular nerve when they join together. Both, the cochlear and the vestibular nerves join to form the vestibulocochlear nerve with a Y shape, with approximately 5 mm in length. The nerve is widely vascularized and presents a complete mixture of the vestibular and cochlear myelinated fibers when the VIII nerve fascicle is constituted. The myelinated fibers are longitudinally oriented and present few endoneural connective tissue in between. No unmyelinated fibers were evidenced in the VIII nerve. The myelinated fiber diameter distribution was unimodal, with a peak at 3.5, and intervals between 1,5 and 6 m. The average number of fibers was 5.390 ± 1.504. The myelinated axon diameter distribution was also unimodal, with a peak at 2.5 µm of diameter were predominant quantitatively: 6.757 ± 1.922, and intervals between 1 and 4.5 µm. The average myelinated fiber density was 41.474 ± 4384 mm2, spread in a fascicular diameter of 0.77 ± 0.04 mm. The g ratio values varied from 0.2 to 0.9 and most of the myelinated fibers showed g ratio values of 0.7. Our results are original and only few parameters studied here were described in the literature. The vestibulocochlear nerve of the guinea pigs is a special afferent nerve, differing from other peripheral nerves (sensitive and motor) in its main anatomic and physiological characteristics, compared to other nerves from mammals. The adult guinea pig is an excellent model for the vestibulocochlear nerve neuropathy studies once it is similar to the human nerve.

Um estudo morfoquantitativo foi realizado no plexo intramural de bexigas urinárias de cobaias (Cavia porcelus) jovens (GI) e idosas (GII). As bexigas foram submetidas aos métodos da NADH-diaforase e da detecção da atividade da acetilcolinesterase. Os neurônios intramurais apresentaram-se isolados ou reunidos em gânglios de pequeno a grande número entre os feixes musculares lisos que constituem o músculo detrusor. O número médio de neurônios NADH-diaforase positivos por bexiga urinária foi de 1.433±187 em GI e de 1.107±120 em GII. Foram observados neurônios arredondados ou ovalados em ambos os grupos, porém o perfil citoplasmático apresentou-se com aspecto relativamente denteado em GII. Em relação a colinesterase, os neurônios de GI apresentaram-se com marcação menos intensa do que em GII. A área média do perfil celular dos neurônios intramurais NADH-diaforase positivos foi de 711,01±28,14µm2 em GI e de 873,30±60,25µm2 em GII, sendo esta a principal diferença morfológica encontrada entre os grupos. / A morphoquantitative study was carried on intramural plexus of the urinary bladder of the young (GI) and old (GII) guinea-pigs (Cavia porcelus). The specimens were stained with NADH-diaphorase and AChE methods. The intramural neurons were observed both isolated or in small and large clusters lying between the bundles of smooth muscle fibers of the detrusor muscle. The mean number of NADH-diaphorase staining neurons per urinary bladder was 1.433±187 in the GI and 1.107±120 in the GII. In both groups, round or elongated neurons were observed. The citoplasmatic contour was indented the animals of GII. The AChE method evidenced intensely reactive neurons in GII when compared with those of the GI. The mean of neuronal profiles was 711,01±28,14mm2 in the GI and 873,30±60,25mm2 in the GII. This observation was the main morphological difference between the GI and GII.

Das Ziel der Untersuchungen bestand darin, mit Hilfe objektiv messbarer Verhaltensreaktionen von Schweinen deren essentielle Ansprüche und Präferenzen zu ermitteln. Der Versuchsaufbau ermöglicht eine permanente Erfassung der Verhaltensabläufe von 22 Mastschweinen über den gesamten Haltungszeitraum. Dies erfolgt durch Anwendung einer elektronischen Identifikation, die Aufenthaltsort, -dauer und -frequenz von jedem Tier erfasst. Als Aufenthaltsorte standen den Tieren ein Bereich zur Nahrungsaufnahme, ein Bereich Ruhen und zwei Beschäftigungsbereiche zur Verfügung. Beide Futterautomaten und Tränken waren mit einer Tieridentifikation ausgestattet. Durch das sensorgestützte System konnten in den zwei Versuchen im Mittel über 6000 Datensätze je Tier erhoben werden. Der Auswertungsschwerpunkt wurde auf die Analyse von Präferenz und Nutzungsstruktur der Beschäftigungsbereiche gelegt. Als Beschäftigung standen den Schweinen Sand, eine neuartige Wühlmatte und Stroh zur Verfügung. Wühlen schien für die Tiere ein wichtiges Verhaltenselement zu sein. Die Nutzungshäufigkeit der Beschäftigung betrug 6-11 Besuche je Tier und Tag. Die potentielle Nutzungsdauer der Beschäftigungsangebote erreichte im Mittel höchstens 3,4 Stunden je Tier und Tag. Die Unterschiede zwischen den Angeboten waren signifikant. Die Individualität der Schweine ist sowohl in der Nutzungsfrequenz als auch - dauer stark ausgeprägt. Der Neuigkeitswert der Beschäftigung gewinnt mit zunehmendem Alter an Bedeutung. Durch eine Modellierung der sensorgestützt erfassten Parameter Nutzungshäufigkeit und Aufenthaltsdauer zu den Beschäftigungsangeboten ist es gelungen, eine objektive Bewertung tierindividueller Präferenz zu zwei Angeboten in einer Indexzahl zu erreichen. Unter Berücksichtigung des Adaptationsprozesses auf veränderte Umweltbedingungen im zeitlichen Verlauf kann mittels des Modells außerdem eine Aussage zur Affinität und Kompensationsmöglichkeit von Angeboten vorgenommen werden. / This study analyses individual requirements and preferences of pigs by measuring objective parameters of their behaviour. In contrary to previous approaches the generated experimental setup enabling long term investigation of 22 pigs behaviour during the whole fattening period. Using sensorbased identification of every single pig it was possible to record habitation, duration of stay and the frequency of attendance in distinct area of the facility namely feeding and drinking area, resting area as well as two areas with environmental enrichment. Furthermore two automatic feeders and the drinkers were equipped with the animal identification system. More than 6000 data sets for each animal were recorded in two independent experimental series. The evaluation focused on the analysis of both preference and utilisation of environmental enrichments such as sand, novel nuzzle mat and straw. It seemed that nuzzling turned out to be essential for the animals, as six to eleven visits per day and animal were recorded. Pigs attended to the respective elements up to 3.4 hours per day. Significant preferences for specific elements could be observed. For individual study animals both frequency and duration of stay were markedly variable. Attractiveness of novel environmental enrichments increased with increasing age of the pigs. By modelling frequency of use and duration of stay, both recorded sensor-based, it was possible to accomplish an objective analysis of the individual preference for specific offers which is represented by an index number. This number supported the results obtained by complex measurements precisely yet in a simplified manner. Taking into account the adaptation process to changing environmental conditions the generated model permits a conclusion regarding affinity and compensation of the offerings.

Schätzung von Kreuzungsparametern unter besonderer Berücksichtigung von epistatischen Effekten und Optimierung des Kreuzungszuchtverfahren beim Meerschweinchen in Bolivien Die vorliegende Arbeit befasst sich mit dem Meerschweinchen als einheimischem Fleischlieferant in den Andenstaaten Lateinamerikas, das im Rahmen der ländlichen Entwicklung durch Züchtung und entsprechende Haltung zu einer besseren Fleischversorgung und evt. zu einer Einkommensquelle insbesondere für Kleinbauern beitragen soll. Ziel der Arbeit ist es, die Kreuzungsparameter, insbesondere epistatische Effekte, zwischen einer synthetischen kleinrahmigen nativen Linie, bestehend aus 29 Herkünften Boliviens, und einer importierten großrahmigen Linie aus Peru unter semi-intensiven/semi-extensiven "modernen" Haltungsbedingungen zu schätzen und daraus Schlussfolgerungen für die Optimierung von Zuchtsystemen zu ziehen. In der Einleitung werden zunächst die biologische Besonderheiten des Meerschweinchens sowie die kulturelle und gesellschaftliche Bedeutung des Meerschweinchens und Haltungssysteme kurz beschrieben. Der Literaturteil befasst sich mit den Genwirkungen bei Kreuzungen, insbesondere den nicht-additiven Geneffekten und der Planung und Optimierung von Kreuzungssystemen. Außerdem wird die Reproduktions- und Produktionsleistung beim Meerschweinchen in Rein- und Kreuzungszucht dargestellt. Der eigenen Untersuchung liegen die Daten von 2857 ersten und zweiten Würfen bzw. von 7745 lebend geborenen Jungtieren vor, die aus der Verpaarung von ca. 391 Böcken mit 1688 Weibchen hervorgingen. Es handelt sich um die am Zuchtprojekt "Mejocuy" der Universidad Mayor de San Simón in Cochabamba, Bolivien, entwickelten nativen synthetischen bolivianischen und der importierten peruanischen Linie sowie 12 daraus abgeleiteten Kreuzungsgruppen verschiedener Generationen (reziproke F1s, reziproke Rückkreuzungen, F2, Vorstufen einer Wechselkreuzung sowie eine synthetische Linie mit je 50% Genanteil der beiden Ausgangspopulationen). Der Schätzung der Kreuzungsparameter liegen das Jakubec-Modell mit drei verschiedenen epistatischen Effekten (Additiv x Additiv-Interaktionen, Additiv x Dominanz-Interaktionen, Dominanz x Dominanz-Interaktionen) sowie das Dickerson-Modell mit dem Rekombinationsverlust als epistatischem Effekt auf individueller (Nachkommen-), maternaler (individueller), paternaler (Paarungspartner-) und großmütterlicher (maternaler) Ebene zu Grunde. Auf Grund der Interkorrelation von Parametern (Multikollinearität) sowie für eine gezielte Herausstellung von Parametern für praktische Züchtungsmethoden und -strategien wurde die Anzahl der Parameter je genetisches Modell auf fünf mit jeweils einem epistatischen Effekt pro Modell beschränkt: Dickerson-Modell: gi, hi, ri, gm, hm bzw. gnk, hnk, rnk, gi, hi; Jakubec-Modell aa: gi, di, aai, gm, dm bzw. gnk, dnk, aank, gi, di; Jakubec-Modell dd: gi, di, ddi, gm, dm bzw. gnk, dnk, ddnk, gi, di. Die synthetische bolivianische Linie stellt die Bezugsbasis dar. GLS- bzw. LS-Zuchtgruppenmittelwerte und Kreuzungsparameter wurden für Merkmale der Gewichts- und Wachstumsleistung, der Schlachtleistung, der Reproduktionsleistung sowie für Kriterien der Gesamtproduktivität geschätzt. Die vorherrschenden Kreuzungseffekte sind Linienunterschiede, die bei den Produktionsmerkmalen positiv gerichtet sind, bei der Anzahl Nachkommen pro Muttertier bzw. pro metabolisches Muttergewicht und Halbjahr negativ. Die genetischen Modelle sowie die Ergebnisse sind im Gesamtzusammenhang diskutiert, und es werden Empfehlungen für Zuchtsysteme mit den untersuchten Linien für die am Untersuchungsstandort spezifischen saisonalen und wirtschaftlichen Verhältnisse sowie für die Selektion gegeben. / Estimation of Crossbreeding Parameters with Special Consideration of Epistatic Effects and Optimisation of Crossbreeding Procedures For Guinea Pigs in Bolivia The present study investigates the guinea pig as a native animal for meat production in the Andean countries of Latin America. In the framework of rural development the guinea pig can contribute to a better meat supply and a source of income especially for small holders by improving breeding and management. The objective of this study is to estimate crossbreeding parameters, focusing on epistatic effects, from crossings between a small framed synthetic native line consisting of 29 Bolivian strains and an imported line from Peru selected for body weight, kept under semi-intensive/semi-extensive "modern" management conditions. Conclusions for the optimisation of breeding systems should also be derivated. In the introduction first the special biological charcteristics as well as the cultural and symbolic meaning of the guinea pig, and management systems, are briefly described. The literature part treats gene effects in crossbreeding, especially non-additive gene effects, as well as the planning and optimization of crossbreeding systems. Also a literature review of the guinea pig reproduction and production performance in pure- and crossbreeding is presented. In the present study, data from 2857 first and second litters and 7745 progenies, stemming from the matings of 391 bucks with 1688 dams were analysed. The animals belong to a native synthetic Bolivian line, developed at the Universidad Mayor de San Simón, Cochabamba, Bolivia, and an imported Peruvian line as well as to 12 crossbreeding groups derived from these stocks: reciprocal F1s, reciprocal backcrosses, F2, pre-rotational groups and a synthetic line with 50% gene proportion of each purebred line. The basic model for the estimation of crossbreeding parameters is the Jakubec model with three different kinds of epistatic effects (additive x additive interactions, additive x dominance interactions, dominance x dominance interactions) and the Dickerson model with the recombination loss as epistatic effect on the individual (progeny), maternal (individual), paternal (male mating partner) and grandmaternal (maternal) level. Because of the intercorrelation of parameters (multicolinearity) and with the objective to estimate the most relevant parameters for practical breeding methods and strategies the number of parameters per genetic model was restricted to five with one epistatic effect, respectively: Dickerson-Modell: gi, hi, ri, gm, hm and gpr, hpr, rpr, gi, hi; Jakubec-Modell aa: gi, di, aai, gm, dm and gpr, dpr, aapr, gi, di; Jakubec-Modell dd: gi, di, ddi, gm, dm and gpr, dpr, ddpr, gi, di (i: individual, m: maternal, pr: progeny). The synthetic native Bolivian line was considered as reference. GLS- and LS-breeding group means and crossbreeding parameters were estimated for body weight and growth traits, reproduction traits and productivity traits. The prevailing crossbreeding effects are line differences with positive signs for production traits and with negative signs for the number of progeny per dam and per metabolic dam weight in the first half year of production. The genetic models and the results are discussed in a global context and recommendations are derived for breeding systems and selection for the investigated lines under the specific seasonal and economical conditions prevailing at Cochabamba, Bolivia.

A Síndrome do Desconforto Respiratório Agudo (SDRA) cursa com insuficiência respiratória e necessidade de ventilação mecânica invasiva (VMI). A mortalidade desta síndrome é elevada, mas pode ser reduzida com o uso de estratégias protetoras de ventilação mecânica que usam baixo de volume corrente (VC), geralmente 6ml/Kg ou menos, para minimizar a lesão causada pelo ventilador. Algumas destas estratégias de ventilação protetora utilizam valores elevados de PEEP que podem produzir instabilidade hemodinâmica. O objetivo deste estudo foi comparar, em um modelo experimental suíno de SDRA, os efeitos hemodinâmicos causados por duas estratégias de ventilação mecânica protetora: uma que utiliza PEEP ajustado pela Tomografia de Impedância Elétrica (OLA) e a outra, a mais comumente utilizada na prática clínica (ARDSNET), em que a PEEP é ajustada através de uma tabela. Foram utilizados 17 animais após randomização (8 no grupo OLA; 9 no grupo ARDSNET) que foram ventilados por 42 horas. As variáveis foram analisadas utilizando ANOVA de medidas repetidas. Antes da radomização, os grupos não apresentavam diferenças nos parâmetros hemodinâmicos e respiratórios. Considerando o período de 42 horas de estudo: 1) o grupo OLA utilizou valores maiores de PEEP, obteve uma melhor oxigenação, mas com valores de PaCO2 mais elevado; não houve diferença entre os grupos para o platô de pressão, mas o delta de pressão foi menor no grupo OLA o que pode minimizar o risco de lesão pulmonar induzida pelo ventilador; 2) o grupo OLA apresentou valores de índice cardíaco (IC) menores durante o estudo, mas não houve um comprometimento aos órgãos alvos conforme pode ser constatado pelos valores normais do lactato arterial e pelos valores de saturação do sangue venoso misto maiores do que no grupo ARDSNET; 3) pela análise de regressão múltipla pode se observar que o aumento da PEEP esteve associado com aumento da pressão média de artéria pulmonar (PMAP), mas redução do IC e da pressão arterial média, enquanto que o aumento da PaCO2 esteve associado com um aumento da PMAP e do IC. Concluímos que uma estratégia ventilatória protetora para SDRA cujo ajuste de PEEP é guiado por TIE, quando comparada com outra estratégia protetora comumente utilizada na prática clínica por um período de 42 horas, determina uso de valores maiores de PEEP, o que melhora a oxigenação e minimiza o delta de pressão, mas causa redução do IC que não resulta em isquemia tecidual. / The Acute Respiratory Distress Syndrome (ARDS) is associated with respiratory failure and need for invasive mechanical ventilation (IMV). The mortality of this syndrome is high, but can be reduced with the use of protective strategies of mechanical ventilation using low tidal volume (VT), usually 6ml/Kg or less, to minimize the damage caused by the ventilator. Some of these strategies of protective ventilation use high levels of PEEP that can produce hemodynamic instability. The aim of this study was to compare, in an experimental pig model of ARDS, the hemodynamic effects caused by two strategies of protective ventilation: one strategy adjusts PEEP values using Electrical Impedance Tomography (EIT-OLA) and the other, the most commonly used in clinical practice (ARDSNET), in which PEEP is adjusted through a table. Seventeen animals were randomized (8 in OLA group; 9 in ARDSNET group) that were ventilated for 42 hours. The variables were analyzed using repeated measures ANOVA. Before randomization, the groups had no difference in hemodynamic and respiratory parameters. Considering the period of 42 hours of study: 1) OLA group used higher values of PEEP, had a better oxygenation but with higher values of PaCO2; there was no difference between groups for the plateau pressure, but the delta pressure was lower in OLA group which can minimize the risk for ventilator-induced lung injury; 2) the OLA group showed lower values of cardiac index (CI) during the study, but there was no damage to target organs as showed by normal blood lactate values and values of mixed venous blood saturation greater than in ARDSNET; 3) multiple regression analysis revealed that, increasing PEEP was associated with increasing in mean pulmonary artery pressure (MPAP), but reduction CI and mean arterial pressure, while increasing in PaCO2 was associated with an increase in MPAP and CI. We conclude that a protective ventilatory strategy for ARDS whose setting of PEEP is guided by EIT, when compared with other protective strategy commonly used in clinical practice for a period of 42 hours requires the use of higher values of PEEP, which improves oxygenation and minimizes delta pressure, but causes reduction of CI that does not result in tissue ischemia.

A busca por novos fármacos inspirados em substâncias de origem natural é uma estratégia conhecida e há tempos utilizada. As lactonas sesquiterpênicas (LST) são um grupo de substâncias amplo e diverso com várias atividades farmacológicas descritas, e cuja característica estrutural determinante é a de um esqueleto principal contendo 15 átomos de carbono e um anel lactônico. O mecanismo de ação das LST está intrinsicamente relacionado com reações de adição do tipo Michael frente a biomoléculas, provocando alquilações. Há na literatura estudos aprofundados sobre a química medicinal das LST, entretanto pouco há sobre o metabolismo desse grupo de substâncias em ambientes fisiológicos. Neste sentido, este trabalho é focado no estudo do metabolismo e também das vias de fragmentação por eletrospray da budleína A, que possui estrutura química do tipo furanoeliangolido, e pertence à classe dos germacranolidos. Foram realizados ensaios in vitro utilizando-se os modelos de oxidação biomimética com metaloporfirina, microssomas hepáticos e metabolismo pela microbiota intestinal de ceco de porco (pig cecum model), sendo nos dois últimos testado também o correlato 4,5-dihidro-2\',3\'-epoxi-15-desoxigoyazensolido. O estudo de fragmentação também abordou a comparação entre budleína A e a centraterina - um estereoisômero que se diferencia apenas pela orientação da cadeia lateral ligada ao C-8 - em espectrômetros distintos e com suporte de métodos computacionais para cálculos de energia (Gaussian 03 em base B3LYP/6-31G(d)). Nos estudos de fragmentação observou-se a diferença de intensidade dos sinais para íons fragmento comuns às duas LST (m/z 275, 257 e 83), além da presença do íon fragmento de m/z 293 apenas para a budleína A, permitindo a diferenciação destes isômeros por meio de espectrometria de massas com ionização por eletrospray, sem a necessidade de ressonância de magnética nuclear. Os produtos de oxidação detectados na reação com metaloporfirinas acusaram a epoxidação na cadeia lateral envolvendo C-2\' e C-3\' com a formação de diastereoisômeros. No ensaio com microssomas não foram detectados produtos para a budleína A, enquanto que para a substância correlata observou-se a abertura do epóxido na cadeia lateral e adição de uma hidroxila, formando um diol vicinal. No modelo de ceco de porco observaram-se a formação de adutos de LST com o aminoácido cisteína, os quais foram posteriormente degradados pela ação da microbiota intenstinal, dando origem a diversos metabólitos compostos pela LST e partes de cisteína. Sendo assim, este trabalho lança bases para a maior compreensão do metabolismo de LST do tipo furanoeliangolido em modelos distintos e também contribui para os estudos de espectrometria de massas para este tipo de substância, além de descrever uma ferramenta analítica útil na diferenciação de dois estereoisômeros. / The search for new drugs inspired on compounds from natural products is a wellknown strategy with several successful cases. Sesquiterpene lactones (STL) are a wide and diversified group of compounds which has already many pharmacological activities reported. Their fundamental moiety includes a skeleton containing 15 carbons and a lactone ring and the mechanism of action is related to Michael addition type reactions with biomolecules, promoting alkylation. There are a high amount of studies regarding the medicinal chemistry of the STL, however there are few information about the metabolism of these compounds under physiological environments. On this way, the aims of this work are focused on the study of the metabolism as well as the fragmentation pathways of budlein A, which is a furanoheliangolide and belongs to the germacranolides class. On this work the following experiments were carried out: in vitro oxidative metabolism with metalloporphyrin and microsomes; intestinal metabolism by using the pig cecum model (microbiota). For microsomes and intestinal metabolism the compound 4,5- dihydro-2\',3\'-epoxy-15-deoxy-goyazensolide was also applied. Fragmentation studies compared the fragmentation patterns of budlein A and centratherin - which is a stereoisomer with -orientation for the side chain bonded at C-8 - by using different spectrometers being supported by computational methods for energies calculations (Gaussian 03 at level B3LYP/6-31G(d)). For the fragmentation studies it was observed the difference of signal intensities for fragment ions which are common for both STL (m/z 275, 257 e 83), moreover the ion m/z 293 was detected only for budlein A, allowing the differentiation between these isomers by electrospray ionization mass spectrometry instead nuclear magnetic resonance. The reactions with metalloporphyrin yielded two diastereoisomers of the STL with an epoxide at the side chain between C-2\'and C-3\'. On the microsome assay any product was detected for budlein A, while for the correlated compound the epoxide ring was opened and a hydroxyl was added at C-3\', forming a vicinal diol. On the pig cecum model it was observed the formation of adducts due to the reaction of the STL and the amino acid cysteine. These adducts were later degraded by the action of the microbiota yielding different metabolites composed by STL and residues of cysteine. Thus, this work may contribute to the improvement of the knowledge about the metabolism of STL furanoheliangolide type in different models as well as for the studies regarding the mass spectrometry of this type of compound. The development of a useful analytical tool for the differentiation of two isomers was also an important achievement.