Treball experimental que parteix de la hipòtesi que l'antibiòtic-lock és un mètode útil pel tractament local de la infecció de catèter. Per aclarir alguns dels dubtes existents amb aquesta forma de tractament, es defineixen els objectius següents: estandarditzar un model animal d'infecció associada a catèter que permeti valorar diverses pautes de tractament sense la retirada del catèter, avaluar la utilitat de l'heparina en el tractament antibiòtic local de la infecció de catèter i avaluar l'eficàcia de diferents pautes antibiòtiques en el tractament local de la infecció de catèter.La tesi estudia en soques de S.aureus aïllades de pacients afectats de sèpsia per catèter dels Hospitals de la Vall d'Hebron de Barcelona: la sensibilitat a heparina, vancomicina, ciprofloxacina i rifampicina en fase de creixement exponencial, estacionari i adherit a catèter, és a dir, formant biocapes bacterianes; l'eficàcia in vitro de les combinacions de vancomicina o ciprofloxacina amb heparina o rifampicina mitjançant el mètode de les corbes de letalitat. També analitza l'estabilitat de vancomicina a la concentració de 2000 mg/mL(V2000) i ciprofloxacina a 1000 mg/mL(C1000) amb heparina a 2500 UI/mL(H2500); així com de V2000, ciprofloxacina a 2000 mg/mL(C2000) i rifampicina a 3000 mg/mL(R3000) soles i les combinacions de V2000 i C2000 amb R3000 fins a 72h. Totes les determinacions es fan per triplicat. Així mateix, aporta un nou model animal d'infecció de catèter en conills New Zealand als que se'ls insereix un catèter de silicona a la vena cava inferior a través de la vena jugular, es tunelitza fins la zona interescapular i s'infecta amb un inòcul de S.aureus de l'ordre de 108ufc/mL mitjançant una injecció intraluminal. A les 18 hores(h) s'inicien els diferents grups de tractament: H2500, V2000 i C1000 soles i les combinacions V2000 i C1000 amb H2500; i V2000, C2000 i R3000 soles i les combinacions de V2000 i C2000 amb R3000, mitjançant injecció intraluminal única en pautes de tractament de 24 o 72h de durada. L'avaluació dels grups de tractament al final del període es fa mitjançant el rentat, el rodatge i el sonicat dels 4 cm distals del segment de catèter. Finalment, s'estudia l'aparició de soques mutants resistents a ciprofloxacina i/o rifampicina. Es troba que l´heparina a concentracions iguals o menors a 6000 UI/mL no té activitat antibacteriana front les soques de S.aureus estudiades; que vancomicina, ciprofloxacina i rifampicina quan s´avaluen davant de bacteris formant biocapes presenten increments poc importants de la concentració inhibitòria mínima però un augment molt considerable de la seva concentració bactericida mínima; en els estudis de les combinacions, l'heparina no representa cap potenciació de l'efecte antibacterià de vancomicina o ciprofloxacina, i la combinació de vancomicina o ciprofloxacina amb rifampicina no demostra major activitat que rifampicina sola. Pel que fa a l'estabilitat, vancomicina i ciprofloxacina romanen estables almenys 72h quan es combinen amb heparina o rifampicina a les concentracions estudiades. Pel que fa als estudis in vivo: s'ha estandarditzat un nou model animal d'infecció de catèter que permet el tractament local de la infecció de catèter mitjançant la tècnica de l´antibiòtic-lock. Els experiments terapèutics han permès concloure que l´heparina per si mateixa no té cap valor en el tractament local de la infecció de catèter, ni sola ni combinada amb els antibiòtics de l'estudi. Dels antibiòtics estudiats, el més eficaç ha estat la rifampicina i el menys la vancomicina; és possible esterilitzar la superfície externa d´un catèter infectat mitjançant l´administració únicament endoluminal d´antibiòtics; el tractament de la infecció de catèter per S.aureus mitjançant l´administració de rifampicina durant 24h facilita l´aparició de soques resistents i això no succeeix si el tractament es perllonga per espai de 72h o es combina rifampicina amb vancomicina o ciprofloxacina. / Experimental work that considers the hypothesis that the antibiotic-lock technique is a useful method for the local treatment of catheter-related infections. To clarify some of the existing doubts with this type of treatment, the following objectives are defined: to standarize an animal model of catheter-related infection that allows an evaluation of different antibiotic treatments without catheter removal, to evaluate the usefulness of heparin in the local antibiotic treatment of the catheter infection and to evaluate the efficacy of different antibiotic treatment regimens in the local treatment of the catheter infection.The thesis studies: the sensitivity to heparin, vancomycin, ciprofloxacin and rifampin in logarithmic growth, stationary and adherent to catheter; the in vitro efficacy of the combinations of vancomycin or ciprofloxacin with heparin or rifampin with the time-kill method, in S.aureus strains isolated in patients with catheter-related sepsis of the Hospitals de la Vall d'Hebron de Barcelona. It also analyzes vancomycin stability at a concentration of 2000 mg/mL(V2000) and ciprofloxacin at 1000 mg/mL(C1000) with heparin at 2500 UI/mL (H2500); and V2000, ciprofloxacin at 2000 mg/mL(C2000) and rifampin at 3000 mg/mL(R3000) alone and the combinations of V2000 and C2000 with R3000 up to 72h. All the determinations are done per triplicate. Furthermore, it introduces a new animal model of catheter-related infection in New Zealand rabbits to which a silicon catheter is inserted into the lower cava vein through the jugular vein, it is tunneled until the interescapular zone and it is infected with an S.aureus inocula of approximately 108ufc/mL with an intralumenal injection. After 18 hours(h) the different treatment groups are started: H2500, V2000 and C1000 alone and the combinations V2000 and C1000 with H2500; and V2000, C2000 and R3000 alone and the combinations of V2000 and C2000 with R3000, in an unique intralumenal injection in therapeutic regimens of 24 or 72h. The evaluation of the therapeutic groups at the end of the study period is done with the flushing, the roll-plate method and the sonication of the distal 4 cm of the catheter. Finally, the appearance of mutant resistant strains to ciprofloxacin and/or to rifampin is also studied. It is found that heparin at concentracions equal or less than 6000 UI/mL does not have antibacterial activity against S.aureus strains; vancomycin, ciprofloxacin and rifampin when evaluated against biofilm forming bacteria, have small increases in the minimum inhibitory concentration but they present a large increase in their minimum bactericidal concentration; in the combination studies, heparin does not represent any improvement in the antibacterial effect of vancomycin or ciprofloxacin, and the combination of vancomycin or ciprofloxacin with rifampicin does not show better activity than rifampin alone. In relation to the stability studies, vancomycin and ciprofloxacin remain stable unless up to 72h when combined with heparin or rifampin at study concentrations. In relation to the in vivo studies: we standardized a new animal model of catheter infection that allows the local treatment of the catheter infection with the antibiotic-lock technique. The therapeutic experiments conclude that heparin alone does not have any value in the local treatment of the catheter infection, neither alone nor combined with the antibiotics studied. Of the antibiotics studied, the most efficacious has been rifampin and the least, vancomycin; it is possible to sterilize the external surface of an infected catheter with the intralumenal injection of antibiotics alone; the treatment of the S.aureus catheter infection with the administration of rifampin during 24h facilitates the appearance of resistant strains and this does not happen if the treatment is extended up to 72h or rifampin is combined with vancomycin or ciprofloxacin.

The thesis presented is a continuation of my bachelor thesis which engaged in the mimetic in nature. In the introductory part there are hypothesis whether Phasmatodea are appropriate didactic group that could be used in the biology and ecology classes, whether there are some easily bred species of Phasmatodea, which could be possibly recommended to scholar insectariums and whether school textbooks for elementary and high schools engage with breeding Phasmatodea and the topic of mimetic. These hypotheses are refuted or confirmed at the end of the thesis. The next part origins from detailed study of many species of Phasmatodea where there are specific species described with detailed information. The next part of the thesis is about breeding few kinds of this sort, the opportunities of beginning the breeding in school environment with advices from real practice, in which way it is possible to manage the insectarium and the breeding and whether Phasmatodea in general can be used as appropriate didactic group in biology and ecology classes. The following part is full of specific motifs of observing and tests in school, thus the didactic use is regarded especially for teachers of elementary and high schools. Both aforementioned parts of the thesis are accompanied by pictures and photographs - some of...

Estimating nutrient and energy requirements of exotic animals is a necessary component of nutrition management in zoos and other wildlife facilities. In the absence of species-specific data, domestic animal models are often referenced. Herbivorous hindgut fermenters, such as horses, zebra, and rhinoceros, rely on microbial fermentation in the cecum and colon to utilize dietary structural carbohydrates. The study objective was to measure the digestible energy of two (LOW, HIGH) complete pelleted diets by the horse as a model for nondomestic hindgut fermenters. Seven, individually housed, adult Quarter Horse (Equus caballus) geldings were assigned to one of two diets as 100% of intake in a randomized crossover design. Experimental diets both contained similar ingredients including soybean oil as an added source of supplemental fat (LOW 1.7%, HIGH 6.9%). Diets differed in predicted digestible energy (LOW 2.29 Mcal/kg, HIGH 2.85 Mcal/kg, DE), ether extract (LOW 4.00%, HIGH 7.41%, EE), and acid detergent fiber (LOW 33.7%, HIGH 26.2%, ADF). Daily feed quantities were offered at 33.3 kcal DE BWkg-1 equally distributed over three meals to maintain target BW. Daily feed intake was quantified. Horses had ab libitum access to water. Horses were transitioned from all forage to 100% test diet over 14 d, acclimated to the test feed for 19 d prior to 4 d acclimation and 6 d total fecal collection using hygiene collection harnesses (Equi-San Marketing Pty Ltd). Diet transition between periods occurred over 8 d. Total fecal output was quantified every 8 h, thoroughly mixed and 10% of measured mass output was subsampled for further analysis. Body weights (BW) recorded weekly did not change significantly throughout the trial (P = 0.420). Apparent digestibility of diet within horse and day was evaluated by a nested ANOVA (Minitab 16). The apparent digestibility of EE (P < 0.000), neutral detergent fiber (P = 0.008), and ADF (P = 0.002) differed between the two diets. Apparent digestibility of DM (P = 0.137), OM (P = 0.140), and GE (P = 0.418) were not different. Excess fat not digested and absorbed in the small intestine (by-pass fat) will enter the hindgut and may cause disruption of normal microbial activity. Additionally soybean oil, when consumed in quantities that allow by-pass to occur, has been shown to have a negative effect on fiber digestibility in hindgut fermenters. A negative effect on fiber digestibility in the higher fat diet could result in diets closer in DM, OM, and GE digestibility than initially predicted. The NRC (2007) recommends that no more than 0.7 g/kg BW/d of soybean oil be fed to the horse. The HIGH diet provided 0.91 g/kg BW/d soybean oil. Feeds that contain concentrations higher than recommended may not be appropriate as the sole dietary ingredient of hindgut fermenters. Further studies are needed to evaluate the use of soybean oil and to determine the threshold at which soybean oil will begin to suppress hindgut fiber digestion. In vivo measurements of digestibility in model species may provide useful benchmarks from which diets for nondomestic hindgut fermenters, as well as horses, may be formulated.

Os modelos experimentais de falência do ventrículo direito (VD) descritos são de difícil execução, por envolverem procedimentos cirúrgicos complexos e dispendiosos, com alta mortalidade e baixa reprodutividade. Também são raros aqueles que promovem falência ventricular exclusiva do ventrículo direito. Com o objetivo de simular a situação clínica de falência ventricular exclusiva do VD, desenvolvemos um modelo experimental de falência crônica isolada do VD, feito através da injeção de etanol intramiocárdico. A disfunção do VD foi induzida em treze cães adultos, através de múltiplas injeções de etanol a 96% (dose total 1ml/kg), na via de entrada e na porção trabecular do VD. Foram analisados parâmetros hemodinâmicos, metabólicos e ecocardiográficos, em condições basais e após indução da falência. Os animais foram mantidos vivos por um período de 14 dias, após o qual foram reoperados e mortos para análise morfológica dos corações. As pressões foram aferidas na artéria femoral, átrio esquerdo (AE), átrio direito (AD), tronco pulmonar (TP) e VD. O fluxo sanguíneo foi medido na aorta e no tronco pulmonar. Na primeira operação, os dados hemodinâmicos foram registrados antes e imediatamente após a indução da falência do VD. Estes parâmetros também foram coletados na reoperação (14 dias pós-indução da falência). Amostras de sangue arterial e venoso foram colhidas simultaneamente ao registro dos parâmetros hemodinâmicos para avaliação dos gases sanguíneos e dosagem de lactato. Foram feitas avaliações ecocardiográficas no pré-operatório, no sexto e no 130 dia pós-operatório (PO). Houve uma mortalidade de 15,4% (2/13). Observou-se uma queda significativa no débito cardíaco pulmonar após a indução da falência e na reoperação (14º PO), quando comparado aos valores medidos no momento basal (p=0,002). Esta queda do desempenho ventricular direito ocasionou um aumento nos valores do lactato venoso, quando comparados os valores basais contra aqueles do pós infusão de etanol (p=0,0001) e com os da reoperação (p=0,0003). Os dados ecocardiográficos revelaram um aumento no volume diastólico do VD, quando comparados os dados basais com aqueles da primeira semana de seguimento (p=0,0001) e com aqueles medidos duas semanas após a indução da falência (p=0,0084). Houve uma queda significativa da fração de ejeção do VD na primeira e segunda semanas em comparação aos valores basais (p=0,0001). A avaliação microscópica feita a partir de amostras retiradas do VD revelou infartos transmurais, com características histológicas compatíveis com infarto de duas semanas de evolução. A injeção de etanol intramiocárdio permitiu a criação de um modelo simples, econômico e reprodutível de falência crônica isolada do VD. A avaliação dos dados hemodinâmicos, ecocardiográficos e bioquímicos medidos nos diferentes momentos do experimento é compatível com a indução de falência grave do VD. Este modelo pode ser útil no estudo da fisiopatologia da falência isolada do VD, bem como na avaliação de assistência ventricular. / Isolated chronic right ventricle (RV) dysfunction is difficult to achieve in experimental models, and sometimes very expensive. Some models require complex surgical procedures, with a high mortality rate and low reproducibility. In order to simulate the clinical status of RV failure, we have developed an experimental model of chronic RV failure by injecting local intramyocardial ethanol 96%. A severe RV dysfunction was induced in 13 mongrel dogs by means of multiple intramyocardial injections of ethanol 96% (total dose of 1ml/kg), in the inlet and trabecular portions of the RV. The hemodynamics, metabolic and ecocardiografic parameters were evaluated at baseline condition and after RV failure. The animals were followed for a 14-day period. After that, they were reoperated for pressure measurements, taken from femoral artery, left atrium (LA), right atrium (RA), RV and main pulmonary artery (PA). Blood flow was measured in the aorta (AO) and PA. Metabolic parameters were assessed simultaneously to pressure measurements, with arterial and venous blood samples withdrawn for gas and lactate analysis, and then, they were killed for morphological evaluation of the heart. All the animals were submitted to echocardiographic evaluation before the first operation, on sixth and on de 13th postoperative day. The mortality rate was 15,4% (2/13). There was a significant decrease in the pulmonary blood flow after RV failure induction (p=0,0018), as well as in the reoperation (p=0,002), as compared to baseline. This decrease in RV performance caused an increase in the venous lactate level, when baseline values are compared with pos infarction values (p=0,001) and reoperation (p=0003). The echocardiografic findings revealed an increased RV diastolic volume on the 6th (p=0,0001) and 13th postoperative day (p=0,0084), as compared to baseline values. Conversely, there was a significant decrease in the RV ejection fraction on the 6th and 13th postoperative day, when compared with baseline values (p=0,0001). Microscopic evaluation of RV samples showed transmural infarctions with histological characteristics aged of two weeks. Intra myocardial ethanol injection has allowed the creation of a simple, inexpensive and reproducible model of chronic RV failure. The hemodynamic, metabolic and echocardiographic parameters assessed in different moments of the protocol are compatible with severe RV failure. It may be useful for RV physiology studies of isolated right sided heart failure, as well as in the assessment of ventricular assist devices.

Os modelos experimentais de falência do ventrículo direito (VD) descritos são de difícil execução, por envolverem procedimentos cirúrgicos complexos e dispendiosos, com alta mortalidade e baixa reprodutividade. Também são raros aqueles que promovem falência ventricular exclusiva do ventrículo direito. Com o objetivo de simular a situação clínica de falência ventricular exclusiva do VD, desenvolvemos um modelo experimental de falência crônica isolada do VD, feito através da injeção de etanol intramiocárdico. A disfunção do VD foi induzida em treze cães adultos, através de múltiplas injeções de etanol a 96% (dose total 1ml/kg), na via de entrada e na porção trabecular do VD. Foram analisados parâmetros hemodinâmicos, metabólicos e ecocardiográficos, em condições basais e após indução da falência. Os animais foram mantidos vivos por um período de 14 dias, após o qual foram reoperados e mortos para análise morfológica dos corações. As pressões foram aferidas na artéria femoral, átrio esquerdo (AE), átrio direito (AD), tronco pulmonar (TP) e VD. O fluxo sanguíneo foi medido na aorta e no tronco pulmonar. Na primeira operação, os dados hemodinâmicos foram registrados antes e imediatamente após a indução da falência do VD. Estes parâmetros também foram coletados na reoperação (14 dias pós-indução da falência). Amostras de sangue arterial e venoso foram colhidas simultaneamente ao registro dos parâmetros hemodinâmicos para avaliação dos gases sanguíneos e dosagem de lactato. Foram feitas avaliações ecocardiográficas no pré-operatório, no sexto e no 130 dia pós-operatório (PO). Houve uma mortalidade de 15,4% (2/13). Observou-se uma queda significativa no débito cardíaco pulmonar após a indução da falência e na reoperação (14º PO), quando comparado aos valores medidos no momento basal (p=0,002). Esta queda do desempenho ventricular direito ocasionou um aumento nos valores do lactato venoso, quando comparados os valores basais contra aqueles do pós infusão de etanol (p=0,0001) e com os da reoperação (p=0,0003). Os dados ecocardiográficos revelaram um aumento no volume diastólico do VD, quando comparados os dados basais com aqueles da primeira semana de seguimento (p=0,0001) e com aqueles medidos duas semanas após a indução da falência (p=0,0084). Houve uma queda significativa da fração de ejeção do VD na primeira e segunda semanas em comparação aos valores basais (p=0,0001). A avaliação microscópica feita a partir de amostras retiradas do VD revelou infartos transmurais, com características histológicas compatíveis com infarto de duas semanas de evolução. A injeção de etanol intramiocárdio permitiu a criação de um modelo simples, econômico e reprodutível de falência crônica isolada do VD. A avaliação dos dados hemodinâmicos, ecocardiográficos e bioquímicos medidos nos diferentes momentos do experimento é compatível com a indução de falência grave do VD. Este modelo pode ser útil no estudo da fisiopatologia da falência isolada do VD, bem como na avaliação de assistência ventricular. / Isolated chronic right ventricle (RV) dysfunction is difficult to achieve in experimental models, and sometimes very expensive. Some models require complex surgical procedures, with a high mortality rate and low reproducibility. In order to simulate the clinical status of RV failure, we have developed an experimental model of chronic RV failure by injecting local intramyocardial ethanol 96%. A severe RV dysfunction was induced in 13 mongrel dogs by means of multiple intramyocardial injections of ethanol 96% (total dose of 1ml/kg), in the inlet and trabecular portions of the RV. The hemodynamics, metabolic and ecocardiografic parameters were evaluated at baseline condition and after RV failure. The animals were followed for a 14-day period. After that, they were reoperated for pressure measurements, taken from femoral artery, left atrium (LA), right atrium (RA), RV and main pulmonary artery (PA). Blood flow was measured in the aorta (AO) and PA. Metabolic parameters were assessed simultaneously to pressure measurements, with arterial and venous blood samples withdrawn for gas and lactate analysis, and then, they were killed for morphological evaluation of the heart. All the animals were submitted to echocardiographic evaluation before the first operation, on sixth and on de 13th postoperative day. The mortality rate was 15,4% (2/13). There was a significant decrease in the pulmonary blood flow after RV failure induction (p=0,0018), as well as in the reoperation (p=0,002), as compared to baseline. This decrease in RV performance caused an increase in the venous lactate level, when baseline values are compared with pos infarction values (p=0,001) and reoperation (p=0003). The echocardiografic findings revealed an increased RV diastolic volume on the 6th (p=0,0001) and 13th postoperative day (p=0,0084), as compared to baseline values. Conversely, there was a significant decrease in the RV ejection fraction on the 6th and 13th postoperative day, when compared with baseline values (p=0,0001). Microscopic evaluation of RV samples showed transmural infarctions with histological characteristics aged of two weeks. Intra myocardial ethanol injection has allowed the creation of a simple, inexpensive and reproducible model of chronic RV failure. The hemodynamic, metabolic and echocardiographic parameters assessed in different moments of the protocol are compatible with severe RV failure. It may be useful for RV physiology studies of isolated right sided heart failure, as well as in the assessment of ventricular assist devices.