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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
601

Gastrointestinal Physiology of Chinook Salmon, Oncorhynchus tshawytscha (Walbaum) with Gastric Dilation Air Sacculitis (GDAS)

Forgan, Leonard George January 2006 (has links)
The syndrome known as Gastric Dilation Air Sacculitis (GDAS) has recently been described by Lumsden et al. (2002) for Chinook salmon (Oncorhynchus tshawytscha, Walbaum), in seawater (SW) culture in New Zealand. The syndrome is characterised by distended abdomens, gastric dilation and air sacculitis, increased feed conversion ratios (FCR) and mortality. Consequently, financial returns on affected stocks are greatly reduced. A study into the epidemiology and physiology of the syndrome was initiated, working with the major aquaculture company, The New Zealand King Salmon Company (NZKS). The study revealed causative factors of GDAS. GDAS was experimentally induced only in saltwater by feeding a commercially manufactured low-cohesion pelleted diet. Control groups were fed a different diet with high physical cohesion. Low-cohesion pellets have previously been associated with a high incidence of GDAS in commercial sea cages. These data implicated osmoregulatory stress and physical properties of the feed in GDAS development. In addition, gastrointestinal (GI) physiology in GDAS -affected and -control fish was characterised. The process of GDAS development in O. tshawytscha is characterised by a loss of smooth muscle tone of the stomach as it distends. Laplace's law (P= 2T/r, where P is the distending pressure, T is the tension in the wall and r is the radius of the cylinder) predicts that unless muscle mass increases, the ability of the stomach wall to contract will be lost and consequently a loss of GI motor function will result. Therefore, GI circular smooth muscle integrity in terms of (1) stimulated and maximal contractility, (2) osmoregulatory ability of the intestine and the (3) control of the GI system was studied in pathologically affected (+ve) and unaffected (-ve) smolt. Affected fish showed changes in GI circular smooth muscle function and osmoregulatory dysfunction. Feeding different diets induced distinct gastric evacuation patterns. The intestinal brake hypothesis is presented and argued to be the probable mechanism for GDAS development. GDAS (+ve) serum showed the presence of factors capable of contracting gut smooth muscle. In addition, potential humoral mediators of the intestinal brake in fish were investigated.
602

Gastrointestinal bacterial communites of Tilapia (Oreochromis mossambicus) and Trout (Oncorhynchus mykiss)

Titus, Phillip Heinrich 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: A 2010 Food and Agriculture Organization (FAO) report indicated that 85% of the world´s fish stocks overexploited. This highlights the importance of commercial aquaculture as a sustainable alternative to capture fisheries. Growth rates for international aquaculture production are slowing, although an average annual increase of 12.6% occurred in Africa between 1970 and 2008. Sub-Saharan Africa accounted for 0.50% of the total world aquaculture production in 2008. The South African aquafeed industry recognized the need for aquaculture research in alternative feed ingredients to ensure a more sustainable future. With routine use of antibiotics in aquaculture, antibiotic resistance have emerged, and novel strategies are needed. Currently, alternative feed ingredients and practical substitution of antibiotics are two of the major challenges faced in aquaculture. The use of plant proteins is preferred over animal proteins such as fish meal. By developing sustainable aquafeeds, that have both nutritional and health benefits, the gastrointestinal tract (GIT) microbiota of the host should be considered. The fish GIT is an open system and acts as a route of infection for pathogenic bacteria. A comparative study was done to determine the structure of the GIT microbiota in Mozambique tilapia (Oreochromis mossambicus) and rainbow trout (Oncorhynchus mykiss). Tilapia and trout are important freshwater aquaculture species in South Africa. Tilapia is a warmwater herbivorous fish with a long coiled GIT, whereas trout is a coldwater carnivore and its GIT is short and compartmentalized. Tilapia was reared in recirculation systems with lower water pH and trout in flow-through systems with higher water pH. Tilapia diets consisted of plant-based protein, whereas trout diets contained animal-based proteins. To understand the role of the autochthonous bacteria in the GITs of these fish, we determined community structure along the length of the respective GITs. A highly reproducible DNA fingerprinting technique, automated ribosomal intergenic spacer analysis (ARISA), was used that targeted the intergenic spacer region (ITS) in bacteria. Community analysis based on operational taxonomic units (OTUs) was used to statistically compare the microbiota in different segments. The different GIT compartments in trout also showed distinct bacterial community structures. However, the degree of variation between identical segments between different fish was shown, and consequently, individual microbiotas was not seen. ARISA was further used to determine if formulations containing dietary phytogenics will modify the GIT microbiota. The GIT of fish plays a role in food digestion, while the resident GIT bacteria are important contributors to disease control and nutrient utilization. During two feeding trials tilapia was fed 16 and trout six different diets. Microbial diversity was lower in the GIT of tilapia as compared to trout and no significant shifts in community structure were detected in both species. With a high-throughput DNA sequencing technique, we followed a metagenomic approach to classify the autochthonous microbiota of tilapia and trout on a phylogenetic level. Pyrosequencing was used to define a core microbiota that would enable comparative feeding studies to be carried out. The proposed microbiota of tilapia consisted of genera from the Proteobacteria (5), Firmicutes (1), Actinobacteria (1), Fusobacteria (1) and Cyanobacteria (2). The microbiota of trout comprised genera of the Proteobacteria (3), Firmicutes (3) and Actinobacteria (1). Three genera from the Proteobacteria were common in tilapia and trout, confirming the dominance of this group in the GIT of freshwater fish. The variability and distribution of Lactobacillus in the GITs of both species was determined. Culturing of lactic acid bacteria (LAB) from the GIT of tilapia proves to be difficult and this was confirmed by the low-abundance of particularly Lactobacillus. A number of other LAB genera were identified that confirmed LAB as part of the autochthonous microbiota in freshwater cultured fish. The detection of secondary bacterial fish pathogens as part of the resident microbiota was also established. The use of 454 pyrosequencing in this study, gave a deeper insight into the structure of bacterial communities in the GITs of tilapia and trout. This research is novel and based on our knowledge, the first study to determine the core microbiota in two South African aquaculture species. Data based on community diversity and structure can be used as a basis for further studies. One important study would be to determine the effect environmental stressors would have on the core microbiota. / AFRIKAANSE OPSOMMING: Volgens `n 2010-verslag van die FAO (Food and Agriculture Organization) is 85% van die wêreld se visbronne oorbenut. Dit beklemtoon die belangrikheid van kommersiële akwakultuur as `n alternatief tot visvangste. Internasionaal neem die groeitempo van akwakultuur produksie af, alhoewel groei in Afrika tussen 1970 en 2008 jaarliks met `n gemiddeld van 12.6% toegeneem het. In 2008 was lande suid van die Sahara verantwoordelik vir 0.50% van die wêreld se akwakultuur produksie. Die Suid-Afrikaanse akwavoer industrie het die behoefte raakgesien vir akwakultuur navorsing in alternatiewe voerbestanddele om 'n meer volhoubare toekoms te verseker. Die roetine gebruik van antibiotika in visboerderye het bygedra tot die ontstaan van weerstandbiedende organismes, en daarom is nuwe strategieë nodig. Tans is alternatiewe voeding en die praktiese vervanging van antibiotiese stowwe belangrike uitdagings in akwakultuur. Die gebruik van plantaardige proteïne in viskos word verkies bo dierlike proteïene soos vismeel. Deur die ontwikkeling van volhoubare viskos, wat beide voedingswaarde en voordele vir die gesondheid van visse inhou, moet die mikrobiota in die spysverteringskanaal (SVK) van die gasheer oorweeg word. Die SVK van visse is `n oop sisteem en dien sodoende as `n infeksie kanaal vir patogeniese bakterieë. `n Vergelykende studie is uitgevoer om SVK mikrobiota struktuur te bepaal in Mosambiek tilapia (Oreochromis mossambicus) en reënboogforêl (Oncorhynchus mykiss). Tilapia en forêl is twee belangrike varswater spesies in Suid-Afrikaanse akwakultuur. Tilapia is `n warmwater herbivoor met `n lang, gekronkelde SVK. In teenstelling is forêl `n kouewater vis met `n kort SVK, wat uit verskillende segmente bestaan. Tilapia is in hersirkulasie waterstelsels met `n lae pH gekweek terwyl forêl in deurvloei waterstelsels met `n hoër pH gekweek is. Tilapia diëte het plantaardige proteïne bevat tewyl forêl diëte proteïne vanaf dier-afkoms bevat het. Om die rol van SVK bakterieë beter te verstaan is populasie struktuur bepaal langs die lengte van die SVK. Geoutomatiseerde ribosomale intergeniese spasie analise (ARISA) is `n herhaalbare DNS vingerafdruk tegniek wat die intergeniese spasies gebied (ITS) in bakterieë teiken. Analise gebaseer op operasionele taksonomiese eenhede (OTEs) is gebruik om die mikrobiota van SVK segmente statisties te vergelyk. Die SVK kompartemente in forêl het ook duidelike bakteriële populasie strukture getoon. `n Groot variasie tussen identiese segmente van verskillende vise is waargeneem en individuele mikrobiota kon nie uitgesonder word nie. ARISA is gebruik om die effek van plantaardige dieet formulasies op die SVK mikrobiota te toets. Die SVK van visse speel `n rol in voedselvertering, terwyl die natuurlike SVK bakterieë `n belangrike rol speel in siektebeheer en die benutting van voedingstowwe. Twee voedingsproewe is op tilapia en forêl uitgevoer, met onderskeidelik 16 en 6 verskillende diëte,. Mikrobiese diversiteit was laer in die tilapia SVK in vergeleke met die SVK van forêl en geen beduidende verskuiwings in populasie struktuur is in beide visse waargeneem nie. `n Hoë deurvloei DNS-volgorde bepalings tegniek, gekombineer met `n metagenomiese benadering is gebruik om die mikrobiota van tilapia en forêl op `n taksonomiese vlak te bepaal. “Pyrosequencing” is gebruik om `n kern microbe populasie te identifiseer ten einde vergelykende studies te vergemaklik. Die voorgestelde kern mikrobiota in tilapia het bestaan uit genera van die Proteobakterieë (5), Firmikute (1), Aktinobakterieë (1), Fusobakterieë (1) en Sianobakterieë (2). Die voorgestelde kern mikrobiota van forêl het bestaan uit genera van die Proteobakterieë (3), Firmikutes (3) en Aktinobakterieë (1). Drie genera van die Proteobakterieë het algemeen in tilapia en forêl voorgekom, wat die oorheersing van hierdie groep in die SVK van varswatervisse bevestig. Die veranderlikheid en verspreiding van Lactobacillus in die SVKs van beide visse is bepaal. Dit is moelik om melksuurbakterieë (MSB) uit die SVK van tilapia te isoleer en `n lae voorkoms van Lactobacillus is waargeneem. Ander MSB genera is ook geïdentifiseer wat MSB as deel van die plaaslike mikrobiota in varswater gekweekte visse bevestig. Verder is daar ook vasgestel dat sekondêre patogene deel uitmaak van die plaaslike mikrobiota. In hierdie studie het 454 “pyrosequencing” `n dieper insig gegee oor die struktuur van bakterie-populasies in die SVK van tilapia en forêl. Hierdie navorsing is oorspronklik en volgens die literatuur die eerste studie wat `n kern mikrobe populasie in twee Suid-Afrikaanse akwakultuur spesies waargeneem het. Data wat gebasseer is op populasie diversiteit en struktuur kan gebruik word as basis vir verdere studies. Een so `n studie kan die effek van omgewings stresfaktore op die kern mikrobiota in hierdie vise bepaal.
603

Modelling nematode infections in sheep and parasite control strategies

Laurenson, Yan Christian Stephen Mountfort January 2012 (has links)
Gastrointestinal parasitism in grazing lambs adversely affects animal performance and welfare, causing significant production losses for the sheep industry. Control of gastrointestinal parasitism using chemotherapeutic treatment is under threat due to the emergence of anthelmintic resistance, thus stimulating research into alternative control strategies. Whilst investigating control strategies experimentally can be costly and time consuming, using a mathematical modelling approach can reduce such constraints. A previously developed model which describes the impact of host nutrition, genotype and gastrointestinal parasitism in a growing lamb, provided an appropriate starting point to explore control strategies and their impact on host-parasite interactions. Two contrasting mechanisms have previously been proposed to account for the occurrence of anorexia during parasitism. These were reductions in either intrinsic growth rate or relative food intake. Thus, the existing individual lamb model was modified to evaluate these mechanisms by exploring the relationship between anorexia and food composition (Chapter 2). For foods that did not constrain food intake, published data was found to be consistent with the predictions that arose from anorexia being modelled as a reduction in relative food intake. Reported genetic parameter estimates for resistance and performance traits appear to vary under differing production environments. In order to explore the impact of epidemiological effects and anthelmintic input on genetic parameter estimates the model was extended to simulate a population of lambs in a grazing scenario (Chapter 3). Whilst estimates of heritabilities and genetic correlations for drenched lambs remained constant, for lambs given no anthelmintic treatment, the heritability of empty body weight (EBW) reduced and the genetic correlation between faecal egg count (FEC) and EBW became increasingly negative with increasing exposure to infective larvae. Thus differences in anthelmintic input and pasture larval contamination (PC) may provide plausible causes for the variation in genetic parameter estimates previously reported. To investigate the interactions between host resistance and epidemiology (Chapter 4) a population of 10,000 lambs were simulated and FEC predictions used to assign the 1,000 lambs with the highest and lowest predicted FEC to ‘susceptible’ (S) and ‘resistant’ (R) groups, respectively. R and S groups were then simulated to graze separate pastures over 3 grazing seasons. The average FEC and PC predictions of these groups diverged during the first 2 grazing seasons and stabilised during the third, such that the difference in FEC predictions between R and S groups were double those predicted when grazed with the population. This was found to be consistent with experimental data. Further, anthelmintic treatment and grazing strategies were predicted to have no impact on the EBW of resistant lambs, suggesting that control strategies should be targeted towards susceptible animals. Targeted selective anthelmintic treatment (TST) has been proposed to reduce risks of anthelmintic resistance with minimal impacts on performance. To describe the short- and long-term impacts of TST and drenching frequency on sheep production and the emergence of anthelmintic resistance, the model was extended to include a description of anthelmintic resistance genotypes within the nematode population (Chapter 5). Reducing the proportion of treated animals was predicted to increase the duration of anthelmintic efficacy, whilst reducing the drenching frequency increased the long-term benefits of anthelmintic on sheep production. Various determinant criteria for use in TST regimes were compared (Chapter 5) including performance traits such as live weight and growth rate, and parasitological traits such as FEC. Using FEC as the TST criterion was predicted to allow the greatest reduction in the number of anthelmintic treatments administered whilst maintaining the highest average EBW, whilst live weight and growth rate were predicted to give little to no improvement in comparison to selecting animals at random for TST. Using estimated breeding values (EBVs) for FEC as the determinant criterion for TST regimes was compared to using measured FEC (Chapter 6). The EBV for true FEC across the entire growth period, akin to perfect genomic selection, was predicted to be a better criterion than measured time-specific FEC (including a sampling error) for a TST regime. EBVs calculated using measured time-specific FEC showed little benefit compared to measured FEC. The information gained from these simulation studies increases our understanding of control strategies and their impact on host-parasite interactions under various scenarios that may not have been possible using experimental methods. It is important to remember that the aim of alternative or complimentary control strategies is to maintain the sustainability of sheep production systems, and as such the production gain of any control strategy needs to be weighed against the financial, labour and time costs involved in implementation.
604

Evaluación radiográfica de partículas demarcadoras radiopacas en el tracto gastrointestinal felino

Díaz Siña, Ricardo Alejandro January 2009 (has links)
Memoria para optar al Título Profesional de Médico Veterinario / Se evaluó radiográficamente, el tiempo de tránsito gastroentérico de partículas demarcadoras radiopacas (PDRO), de 1 y 5 mm. de diámetro, construidas manualmente de acrílico autopolimerizante de uso odontológico, monómero líquido y sulfato de bario, en 20 gatos clínicamente sanos, basado en los resultados de la examinación física y el examen clínico. Los marcadores fueron administrados a los gatos junto a un alimento estándar y se tomaron radiografías abdominales durante el tiempo, hasta las 48 horas de estudio. Se confeccionaron patrones de tiempo de vaciamiento gástrico y de tránsito intestinal de los marcadores radiopacos junto al alimento, además de establecer valores de referencia para el gastroéntero; es así que en estómago el tiempo necesario para el vaciamiento gástrico del 50% de los marcadores, se encuentra entre las 8 a 12 horas de ingeridas las esferas. La totalidad de los marcadores se eliminó desde estómago entre las 24 a 36 horas de estudio. Hubo diferencias estadísticamente significativas en el vaciamiento gástrico de las esferas pequeñas v/s las grandes en los tiempos 15 y 30 minutos, 4 y 8 horas respectivamente. El tiempo requerido para el tránsito del 50% de los marcadores radiopacos a través de intestino delgado fue de 8 a 12 horas. El 100% ingresó a intestino grueso entre las 36 a 48 horas. Diferencias estadísticamente significativas de tránsito, fueron determinadas en los tiempos 15 y 30 minutos, 4 y 8 horas (mismos tiempos que en estómago), a favor de los marcadores pequeños. En el intestino grueso hubo diferencias estadísticamente significativas en la eliminación de los marcadores en el tiempo 36 horas, pero en este caso las diferencias son a favor de las PDRO grandes. El análisis de las fecas permitió recuperar la totalidad de las partículas demarcadoras ingeridas 2 por los gatos, las que no evidenciaron alteraciones en su estructura ni en sus características radiográficas. No se observó signología de tipo digestiva o de otra índole que pudiese asociarse al uso de acrílico en los marcadores radiopacos, permitiendo concluir que la utilización de ellos es muy valiosa para fines diagnósticos de la motilidad gastrointestinal, y no habría inconvenientes en su utilización.
605

Physical and psychological characteristics in adolescence and risk of gastrointestinal disease in adulthood

Melinder, Carren Anyango January 2017 (has links)
Background and objectives: Physical fitness and stress resilience may influence the risk of gastrointestinal (GI) disease. High physical fitness level may reduce levels of systemic inflammation while psychosocial stress exposure can increase inflammation levels and intestinal permeability. The main objectives are to evaluate if poorer physical fitness and stress resilience in adolescence are associated with a raised risk of inflammatory bowel disease (IBD), peptic ulcer disease (PUD) and GI infections in adulthood and to assess evidence of causality. Materials and methods: Swedish registers provided information on a cohort of approximately 250,000 men who underwent military conscription assessments in late adolescence (1969 –1976) with follow-up until December 2009 (up to age 57 years). Cox regression evaluated the associations of physical fitness and stress resilience in adolescence with subsequent GI disease risk in adulthood. Results and conclusions: IBD: Poor physical fitness was associated with an increased risk of IBD. The association may be explained (in part) by prodromal disease activity reducing exercise capacity and therefore fitness. Low stress resilience was associated with an increased risk of receiving an IBD diagnosis. Stress may not be an important cause of IBD but may increase the likelihood of conversion from subclinical to symptomatic disease. PUD: Low stress resilience was associated with an increased risk of PUD. This may be explained by a combination of physiological and behavioural mechanisms that increase susceptibility to H. pylori infections and other risk factors. GI infections: Low stress resilience was associated with a reduced risk of GI infections, including enteric infections rather than the hypothesised increased risk.
606

Isolation and characterization of prebiotic oligosaccharides from algal extracts and their effect on gut microflora

Hadebe, Nontando January 2016 (has links)
Submitted in partial fulfillment for the Degree of Master of Applied Sciences in Biotechnology, Durban University of Technology, Durban, South Africa, 2016. / Prebiotics are defined as non-digestible oligosaccharides (NDOs) or polysaccharides (NDPs), which promote the growth of beneficial lactic acid bacteria in the colon. Algae are rich in polysaccharides and can be exploited as prebiotics for functional food ingredients to improve human and animal health. Currently, inulin is the most widely used ingredient in the prebiotics market, which is produced from live plants and requires expensive production processing. There is a vast repository of marine life with algae as a major source of nutrients. Therefore, this study provides an alternative source for prebiotic production and examines marine and freshwater algae that promote the growth of two strains of Lactobacillus delbrueckii subs. (Lactobacillus lactis and Lactobacillus bulgaricus) and one strain of Bifidobacterium spp. (Bifidobacterium longum). Monosaccharides of the oligosaccharide fraction of marine and freshwater algal extracts were investigated with the use of thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) after acidic hydrolysis of cell matrix polysaccharides. A total of fifty-five marine and freshwater aqueous algal extracts were assessed for their effect on the growth of L. lactis, B. longum and L. bulgaricus over a 96 hour period. Relative to the negative control, 34.5% algal extracts showed improved growth on one or more probiotic bacteria. The optimum time for maximum bacterial growth was noted at 48 h for all the tested aqueous algal extracts. Five marine and freshwater algal cultures (Spirulina platensis, Chlorococcum spp., Dunaliella salina, Scenedesmus magnus, Chlorella spp. and algal extract no. 48) from various aquatic environments in Kwa-Zulu Natal showed the best growth dynamics and demonstrated the greatest potential as sources of biomass for prebiotic production. These algal extracts were able to significantly increase the growth of at least one of the three probiotic bacteria (p < 0.05). Aqueous algal extract from S. platensis was regarded as the best algal source for prebiotics as it demonstrated a greater stimulatory effect on the growth of all three probiotic bacteria (L. lactis, B. longum and L. bulgaricus) compared to tested aqueous algal extracts and the inulin used as a positive control. The results obtained by HPLC for characterization confirmed TLC data, as xylose and galactose were detected by both chromatograms. These data indicated that xylose and galactose were present in aqueous algal extracts from S. magnus and S. platensis and galactose in aqueous algal extract no. 48. Xylose was most abundant in aqueous algal extracts from S. platensis (3mg/ml) and S. magnus (2.3mg/ml). In conclusion aqueous algal extracts from S. platensis, Chlorococcum, D. salina, S. magnus, Chlorella and algal extract no. 48 are potential sources for prebiotic production. Spirulina platensis extract was regarded as the best algal source. Xyose and galactose characterized by HPLC in algal extracts make up oligosaccharides that function as prebiotic compounds for stimulation of probiotic bacteria. There is a great scope for successful production of prebiotics from algal sources in South Africa. / M
607

Characterization of mechanism of action of hydrogen sulfide (H2S) in the regulation of smooth muscle function

Nalli, Ancy D 01 January 2015 (has links)
Hydrogen sulfide (H2S) is receiving increasing interest, as much as nitric oxide (NO) and carbon monoxide have received previously, to understand its physiological functions as it meets all the criteria to define as a third gasotransmitter. Endogenous synthesis from L-cysteine via cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS) and the function of H2S as an inhibitor of smooth muscle contraction in gastrointestinal tract are known. However, the loci of generation and action of H2S, and the mechanism of inhibition of contraction are unknown. Hence, my aims in the present study are to: i) identify the expression of enzymes in smooth muscle, ii) determine the effects of endogenously released and exogenously applied H2S on smooth muscle function; and iii) identify the targets and mechanism involved in mediating the effects of H2S using isolated smooth muscle cells from rabbit colon. I have identified the expression of CSE, but not CBS, in smooth muscle and demonstrated that L-cysteine (an activator of CSE) and NaHS (H2S donor): 1) inhibited carbachol-induced contraction in muscle strips and isolated muscle cells that was independent of KATP channels, a known S-sulfhydration target of H2S; 2) induced S-sulfhydration of small G protein, RhoA leading to inhibition of RhoA and Rho kinase activities, a key pathway in the sustained smooth muscle contraction; and 3) inhibited PDE5 activity leading to augmentation NO-induced cGMP formation and muscle relaxation. Sodium nitroprusside (an NO donor) induced an increase in H2S production via PKG-dependent phosphorylation and activation of CSE. We conclude that smooth muscle cells selectively express CSE, and endogenous generation of H2S via activation of CSE inhibits muscle contraction and augments muscle relaxation. Inhibition of contraction is mediated via S-sulfhydration of RhoA and suppression of RhoA/Rho kinase pathway. Augmentation of relaxation is mediated via inhibition of PDE5 activity and stimulation of cGMP/PKG pathway, which in addition initiates generation of H2S via PKG-mediated phosphorylation and activation of CSE. The findings are important in providing the underlying mechanisms involved in the regulation of smooth muscle function by H2S and could offer insights for the development of therapeutic agents that may act on smooth muscle in the gut to treat motility disorders.
608

Lékové interakce léčiv gastrointestinálního traktu / Drug interactions of gastrointestinal drugs

Lapka, Marek January 2014 (has links)
Drug interactions of gastrointestinal remedies Author: Marek Lapka Tutor: Josef Malý1 1 Department of Clinical and Social Pharmacy, Charles University in Prague, Faculty of Pharmacy in Hradec Králové Background: Drug interactions may be a serious cause of toxicity and undesirable drug effects. There is a direct proportion to side effect incidence caused by drug interactions and number of used drugs. The issue is a significant constituent of pharmaceutical care. The aim of dissertation: The aim of the thesis was to process available information, suggest a posible solution and create compact overview which can be taken into consideration by pharmacist in order to achieve optimal pharmacotherapy. Methods: Drug combinations, which interactions had clinical evaluation from "moderate severity" to "major severity" were collected from the fundamental information source, Vademecum infopharm aplication. Only currently registered drugs to 1st September 2013 by State Institute for Drug Controle were chosen and then medicinal products of which route of administration enables systemic effect. Furthermore the combination was compared with Micromedex database or Stockley's Drug Interactions Pharmaceutical Press, or both. Pubmed database (www.pubmed.gov) with entering key words "drug interaction", "basic drug" and...
609

Effect of cefovecin on the fecal flora of healthy dogs

Lawrence, Megan Rene January 1900 (has links)
Master of Science / Department of Biomedical Sciences / Sanjeev K. Narayanan / Cefovecin is an extended-spectrum long-acting third generation cephalosporin used to treat canine infections. The study objective was to determine the effect of cefovecin on the absolute number and antimicrobial susceptibility of fecal enteric bacteria in healthy dogs. Fourteen Beagles were randomly assigned to a treated (n = 7, 8 mg/kg cefovecin subcutaneously on day 1) or untreated (n = 7) group. LC/MS was used to determine plasma cefovecin concentration on day 14. E. coli, enterococci, and Salmonella were isolated and enumerated from fecal samples collected on days 0, 3, 7, 14, and 28. Antimicrobial resistance was determined using disc diffusion, MIC, and detected using PCR for the bla[subscript CMY-2] gene on select isolates. Mean plasma concentration of cefovecin on day 14 was 9.59 µg/mL in treated dogs; untreated dogs had no measurable plasma cefovecin. The absolute number of E. coli was lower in treated dogs on day 3 (P ≤ 0.0001), and the absolute number of cefovecin-resistant E. coli was higher in treated dogs on days 7 (P = 0.002), 14 (P = 0.004) and 28 (P ≤ 0.0001), compared to untreated dogs. Enterococci increased and were higher in the treatment group on day 7 (P = 0.0226). Isolation of Salmonella was rare. After cefovecin treatment, beta-lactam resistance was more common in fecal E. coli from treated dogs than untreated dogs, while resistance of enterococci was not altered. On day 28, treated dogs were 3.25 times more likely to carry the bla[subscript CMY-2] gene than untreated dogs (95% CI 1.27 – 8.35). The implications of these findings in clinically ill patients require further research.
610

Efeito do consumo diário de suco de laranja sobre a microbiota intestinal, composição corporal e perfil lipídico e glicídico de mulheres /

Fidélix, Melaine Priscila. January 2018 (has links)
Orientador: Thais Borges Cesar / Banca: Paula Garcia Chiarello / Banca: Renata Maria Galvão de Campos Cintra / Banca: Anderson Marliere Navarro / Banca: Katia Sivieri / Resumo: Introdução: Aos compostos do suco de laranja 100% puro (SL) são atribuídos várias propriedades biológicas, como atividade antioxidante, anti-hipertensiva, redutora do colesterol e glicemia sanguíneos, e atualmente estudos in vitro têm mostrado que o suco de laranja pode ter ação seletiva sob a microbiota intestinal. Objetivo: Investigar o impacto do consumo diário de suco de laranja sobre a microbiota intestinal e no perfil glicídico e lipídico em mulheres. Métodos: Foram avaliadas 10 mulheres por período de 120 dias, distribuídos em três etapas: (1ª): dieta livre de citrus 30º dia (30 dias); (2ª) ingestão de 300 mL/dia de SL 90º dia (60 dias); (3ª) dieta livre de citrus 120º dia (30 dias). Avaliação dietética e antropometria foram realizadas quinzenalmente durante o período experimental. Foram colhidas amostras de sangue, urina e fezes, no início do estudo e a cada 30 dias, até o final do experimento. Foi realizado: analise dos parâmetros bioquímicos; identificação dos metabólitos urinários por UHPLC-UV-VIS; e análise da composição da microbiota por sequenciamento de gene RNAr 16S. Resultados: A avaliação da composição corporal e a excreção urinária não mostraram alterações durante as etapas experimentais. Os parâmetros bioquímicos mostraram diminuição da glicose (-6,25%), da insulina (-32,7%) e da resistência à insulina (-43,8%), além do colesterol total (-13,9%), LDL (-16%) e triglicerídeos (-30%) com a ingestão de SL (90º dia). Após a parada do consumo de SL (120º dia), o... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Introduction: 100% pure orange juice (OJ) compounds are assigned to various biological properties, such as antioxidant, antihypertensive, blood cholesterol lowering and glycemia activity. Currently, in vitro studies have shown that orange juice can present selective action of intestinal microbiota. Objective: To investigate the impact of daily consumption of orange juice on the intestinal microbiota and on the lipid and glucose profile in women. Methods: Ten women were evaluated for 120 days at three differen stages: (1st) citrus-free diet 30th day (30 days); (2nd) intake of 300 mL / day SL 90th day (60 days); (3rd) citrus-free diet 120th day (30 days). Dietary assessment and anthropometry were performed biweekly during the experimental stages. Samples of blood, urine and feces were taken at the beginning of the study, and every 30 days until the end of the experiment. It was carried out: analysis of the biochemical parameters; identification of urinary metabolites by UHPLC-UV-VIS; and analysis of the composition of the microbiota by 16S rRNA gene sequencing. Results: Changes during the experimental stages were not found in evaluation of body composition and urinary excretion. Biochemical parameters showed a decrease in glucose (-6.25%), insulin (-32.7%) and insulin resistance (-43.8%), total cholesterol (-13.9%), LDL (-16%) and triglycerides (-30%) with ingestion of OJ (90th day). After stopping OJ intake (120th day), the biochemical parameters returned to the initial values... (Complete abstract click electronic access below) / Doutor

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