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Introduction: Gastric and colon cancer are major causes of mortality and morbidity worldwide. Gastric cancer is often detected at an advanced stage and current chemotherapeutics are only modestly effective against this neoplasm. Novel chemotherapeutics, chemopreventive agents and treatment strategies are required to prevent and treat gastric cancer. The ideal method to eliminate cancer cells may be the induction of apoptosis, further preventing cell proliferation and tumour growth. Recently, short-chain fatty acids (SCFAs) butyrate and propionate have been investigated as potential chemotherapeutic agents, particularly in colon cancer. Butyrate is reported to induce apoptosis in colon cancer cells and is demonstrated to modulate intracellular redox state by altering the levels of an antioxidant, glutathione (GSH). GSH availability is controlled by the oxidative pentose pathway (OPP). Very few studies have investigated the effects of butyrate on cell types other than colon cancer cells, and even less is known regarding the effects of propionate. This thesis investigated the potential for SCFAs to induce apoptosis in a gastric cancer cell line, Kato III, compared to the colon cancer cell line, Caco-2. Cell cycle regulation, OPP activity, GSH availability and glucose metabolism were also assessed. Methods: Initial studies developed a new technique to measure 1-13C-D-glucose metabolism. Following this, Kato III and Caco-2 colon carcinoma cells were treated with butyrate or propionate (1mM, 5mM or 10mM) or a 5mM combination of both SCFAs. The induction of apoptosis and cell cycle alterations by these SCFAs were assessed using flow cytometry. OPP activity and GSH availability were assessed in both cell lines using colorimetric techniques. Butyrate metabolism was assessed using 13C-butyrate. Results: Butyrate and propionate significantly induced apoptosis and G2-M arrest in Kato III and Caco-2 cells, although to a significantly greater extent in the latter cell line. Moreover, butyrate induced apoptosis to a significantly greater extent than propionate, in both cell lines. SCFA treatment led to the significant up-regulation of OPP activity in both cancer cell lines while GSH availability was significantly reduced. Glucose metabolism was initially increased by all SCFA treatments, however, 72hr butyrate treatment led to its reduction. Importantly, glucose metabolism was measured using a new technique developed within this thesis. The rate of butyrate metabolism was demonstrated to correlate with the sensitivity of each cell line to this SCFA. Conclusions: This thesis provides evidence that SCFAs, particularly butyrate, induce apoptosis in gastric and colon cancer cells in vitro. The response of cancer cells to SCFAs appears complex, and involves multiple distinct mechanisms and pathways, including p53, Fas, changes to intracellular redox state and glucose metabolism. The capability of butyrate to induce apoptosis also appears to be directly related to the rate of its metabolism. Butyrate has the potential to be utilised as an adjunctive therapy for the treatment of gastric cancer and colon cancer. / Thesis (Ph.D.) -- School of Molecular and Biomedical Science, 2007

Thesis--University of California, Berkeley, 1959. / "Chemistry General" -t.p. "TID-4500 (15th Ed.)" -t.p. Includes bibliographical references (p. 38-39).

Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xv, 220 p.; also includes graphics (some col.). Includes bibliographical references (p. 189-201). Available online via OhioLINK's ETD Center

Master of Science / Department of Biological and Agricultural Engineering / Mei He / Thermobifida fusca, an aerobic moderately thermophilic, filamentous soil bacterium is capable of producing butyric acid. Butyric acid is a 4-carbon short chain fatty acid that is widely used in the chemical, food, and pharmaceutical industries. Currently, butyric acid is primarily produced through petroleum-based chemical synthesis, but could be a candidate to be produced by fermentation. By producing through a fermentation platform, production of butyric acid can be shifted from a non-renewable to a renewable source. In an effort to make T. fusca produce a high yield of butyric acid, multiple fermentation parameters were explored and optimized. The effect of different carbon sources (mannose, xylose, lactose, cellobiose, glucose, sucrose, and acetates) on butyric acid production was studied, where cellobiose produced the highest yield of 0.67 g/g C (g-butyric acid/g-carbon input). The best stir speed and aeration rate for butyric acid production were found to be 400 rpm and 2 vvm in a 5-L fermentor. The maximum titer of 2.1 g/L butyric acid was achieved on 9.66 g/L cellulose. Fermentation was performed on ground corn stover as a substrate to evaluate the production of butyric acid on lignocellulosic biomass, and the optimized conditions resulted in a titer of 2.37 g/L butyric acid. The butyric acid synthesis pathway was identified involving five genes that catalyzed reactions from acetyl-CoA to butanyol-CoA in T. fusca. A study into the transcriptomics of T. fusca was begun by growing T. fusca under a variety of fermentation conditions, isolating the messenger RNA, and performing a sequence of the mRNA using whole transcriptome shotgun sequencing. The results of sequencing of various samples were plotted to determine correlation across numerous fermentation parameters. This correlation based analysis determined that the carbon to nitrogen ratio has the largest overall impact on gene transcription of T. fusca among all of the fermentation parameters studied. Overall, the work from this study proves that production of butyric acid is possible from a renewable cellulosic feedstock.

The effects of the inhibitory neurotransmitters gammaamino butyric acid (GABA) and glycine were characterized on spontaneous activity recorded from mouse spinal cord cultures. The GABA concentration which completely inhibited burst activity was chosen as a quantifiable measure of culture drug response and was used to 1) assess interculture and intraculture variability, 2) determine the influence of culture age and initial activity on GABA responses, and 3) compare the GABA responses between networks obtained from whole spinal cord and ventral half spinal cord. Results showed that 1) no significant variability existed either within or among cultures, 2) the initial culture activity directly affected GABA responses, 3) the culture age had no effect on GABA responses, and 4) there was no significant difference in GABA responses between the two spinal cord tissues.

Yes / Several bacterial families are known to be highly abundant within the human microbiome, but their ecological roles and evolutionary histories have yet to be investigated in depth. One such family, Lachnospiraceae (phylum Firmicutes, class Clostridia) is abundant in the digestive tracts of many mammals and relatively rare elsewhere. Members of this family have been linked to obesity and protection from colon cancer in humans, mainly due to the association of many species within the group with the production of butyric acid, a substance that is important for both microbial and host epithelial cell growth. We examined the genomes of 30 Lachnospiraceae isolates to better understand the origin of butyric acid capabilities and other ecological adaptations within this group. Butyric acid production-related genes were detected in fewer than half of the examined genomes with the distribution of this function likely arising in part from lateral gene transfer (LGT). An investigation of environment-specific functional signatures indicated that human gut-associated Lachnospiraceae possess genes for endospore formation, whereas other members of this family lack key sporulation-associated genes, an observation supported by analysis of metagenomes from the human gut, oral cavity, and bovine rumen. Our analysis demonstrates that adaptation to an ecological niche and acquisition of defining functional roles within a microbiome can arise through a combination of both habitat-specific gene loss and LGT. / Canadian Institute for Health Research (grant number CMF-108026), Genome Atlantic and the Canada Research Chairs program to R.G.B.

Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Jason J. Griffin / Heat and drought tolerance make shantung maple (Acer truncatum) and caddo sugar maple (A. saccharum) good candidates for midwestern landscapes. Improving cutting propagation or mound layering techniques could increase the availability of these species. The influence of time of year, cutting position, and auxin concentration, formulation, and solvent on rooting of stem cuttings of shantung maple was investigated. Semi-hardwood cuttings rooted best (55%). Generally, rooting percentage decreased as indole-3-butyric acid (IBA) concentration increased. Cutting position, auxin formulation, and solvent did not affect rooting. Mean root number and mean root length were unaffected by treatments. Results suggest semi-hardwood cuttings and low IBA concentrations [< 2500 ppm (0.25%)] promote rooting. Auxin concentration influenced rooting of caddo and shantung maple mound layered shoots. Rooting peaked at 15,000 ppm (1.5%) IBA for both caddo (71%) and shantung maples (34%). Mean root number for caddo, but not shantung, increased as IBA concentration increased. Differences in mean root length were not significant. Growers may now propagate caddo maple by mound layering. For shantung maple propagation, stem cuttings are recommended. Propagation substrates can strongly influence rooting success of stem cuttings. Eastern redcedar (Juniperus virginiana) chips (ERC) have been suggested as a propagation substrate component. This report investigated ERC as a perlite substitute in a 3 perlite: 1 sphagnum peat moss (v/v) rooting substrate. Stem cuttings of spreading euonymus (Euonymus kiautschovicus), forsythia (Forsythia x intermedia), English ivy (Hedera helix), lantana (Lantana camara), and coleus (Solenostemon scutellarioides) were rooted in substrates containing increasing concentrations of ERC hammer milled to pass a 4.8 mm (0.19 in) screen. All species rooted well (≥95%) in all substrates except forsythia which rooted poorly in all substrates (8% to 36%). ERC did not affect mean root number or mean root length in any species except spreading euonymus where mean root number peaked at 0% and 100% ERC content and mean root length decreased with increasing ERC content. Bulk density, container capacity, and total porosity increased as ERC replaced perlite. Physical properties of all substrates were suitable for cutting propagation. ERC can effectively replace perlite in rooting substrates for many ornamental species.

Ensaios em reator em batelada foram conduzidos para avaliar a produção biológica de hidrogênio a partir de diferentes concentrações de celulose (E1:2,0 g.L-1; E2: 5,0 g.L-1 e E3: 10,0 g.L-1) em pH inicial de 6,8 a 37°C. O objetivo do trabalho foi analisar o lodo de estação de tratamento de efluentes de indústria de papel e celulose como inóculo para obtenção de um consórcio celulolítico e fermentativo. Os ensaios foram monitorados por 16 dias com análises de carboidratos, DQO, pH, ST, STV, biogás, ácidos orgânicos e álcoois, além de análises de caracterização filogenética do Domínio Bacteria. Nos três ensaios, a produção de hidrogênio foi detectada a partir do quarto dia, provavelmente devido ao tempo necessário para hidrólise da celulose. Os dados de produção de hidrogênio foram ajustados ao modelo de Gompertz modificado, sendo calculado o potencial máximo de produção de H2 (P) de 1,23 mmol para E1, 3,14 mmol para E2 e 2,33 mmol para E3. Para os ensaios E1 e E2 observou-se rendimentos de H2 semelhantes; ou seja, de 0,62 mmol H2.g-1 de celulose. Para o ensaio E3 observou-se 0,23 mmol H2.g-1 de celulose. Ácido butírico foi o principal ácido orgânico observado em 2,2, 1,8 e 2,2 g.L-1 para E1, E2 e E3, respectivamente. A fase de diminuição da produção de H2 foi acompanhada pela evolução de metano, ácido acético e sulfeto nos três ensaios. Na visualização microscópica de amostras dos ensaios foi possível averiguar a presença de variedade de formas e arranjos bacterianos corroborando para heterogeneidade do inóculo. Em relação à análise filogenética foram identificados, com mais de 95% de similaridade, gêneros de bactérias reconhecidamente produtoras de H2 e associadas a ambiente com substratos lignocelulósicos, tais como, Clostridium sp., Klebsiella sp. e Raoultella sp., além de consumidoras de H2 Clostridium sp., por homoacetogênese e Desulfovibrio sp. por sulfetogênese. A partir das análises dos resultados, foi possível afirmar que houve produção biológica de hidrogênio a partir de celulose como substrato e lodo de ETE industrial como inóculo. / Batch assays in anaerobic reactors were conducted to evaluate the biological production of hydrogen from different concentrations of cellulose ( E1: 2.0 g.L-1; E2: 5.0 g.L-1 and E3: 10.0 g.L-1) in initial pH of 6.8 at 37 ° C. The aim of this study was analize the sludge of a treatment plant of pulp and paper industry wastewater as inoculum in the anaerobic reactors. The assays were monitored for 16 days by analyses of total soluble carbohydrates, COD, pH, TS, TVS, biogas and organic acids and alcohols. Phylogenetic characterization was carried out for microrganisms of the Bacteria Domain by cloning and sequencing analysis. The hydrogen production was detected on the fourth day of the incubation for the three experimental conditions, probably due to the period required for cellulose hydrolysis. Hydrogen production data were adjusted to the modified Gompertz model, and the maximum hydrogen production potential (P) were 1.23 mmol for E1, 3.14 mmol for E2 and 2.33 mmol for E3. Similar hydrogen yields were observed for assays E1 and E2; ie 0.62 mmol H2.g-1 of cellulose. For E3 the yield was 0.23 mmol H2.g-1 cellulose. Butyric acid was the major organic acid observed with 2.2, 1.8 and 2.2 g.L-1 to E1, E2 and E3, respectively. Hydrogen depletion in the biogas was accompanied by the evolution of methane, acetic acid and sulfide in the three tests. By means of microscopic visualization of microrganisms samples it was possible to determine the presence of a variety of bacterial shapes and confirming the heterogeneity of the inoculum. Regarding phylogenetic analysis, there were identified, with more than 95% similarity, genera of bacteria known as hydrogen producers or related with environments associated with lignocellulosic substrates such as Clostridium sp. Klebsiella sp. and Raoultella sp., consuming genere were also detedted, such Clostridium sp. by homoacetogênese and Desulfovibrio sp. by sulfidogenesis.

Ensaios em reator em batelada foram conduzidos para avaliar a produção biológica de hidrogênio a partir de diferentes concentrações de celulose (E1:2,0 g.L-1; E2: 5,0 g.L-1 e E3: 10,0 g.L-1) em pH inicial de 6,8 a 37°C. O objetivo do trabalho foi analisar o lodo de estação de tratamento de efluentes de indústria de papel e celulose como inóculo para obtenção de um consórcio celulolítico e fermentativo. Os ensaios foram monitorados por 16 dias com análises de carboidratos, DQO, pH, ST, STV, biogás, ácidos orgânicos e álcoois, além de análises de caracterização filogenética do Domínio Bacteria. Nos três ensaios, a produção de hidrogênio foi detectada a partir do quarto dia, provavelmente devido ao tempo necessário para hidrólise da celulose. Os dados de produção de hidrogênio foram ajustados ao modelo de Gompertz modificado, sendo calculado o potencial máximo de produção de H2 (P) de 1,23 mmol para E1, 3,14 mmol para E2 e 2,33 mmol para E3. Para os ensaios E1 e E2 observou-se rendimentos de H2 semelhantes; ou seja, de 0,62 mmol H2.g-1 de celulose. Para o ensaio E3 observou-se 0,23 mmol H2.g-1 de celulose. Ácido butírico foi o principal ácido orgânico observado em 2,2, 1,8 e 2,2 g.L-1 para E1, E2 e E3, respectivamente. A fase de diminuição da produção de H2 foi acompanhada pela evolução de metano, ácido acético e sulfeto nos três ensaios. Na visualização microscópica de amostras dos ensaios foi possível averiguar a presença de variedade de formas e arranjos bacterianos corroborando para heterogeneidade do inóculo. Em relação à análise filogenética foram identificados, com mais de 95% de similaridade, gêneros de bactérias reconhecidamente produtoras de H2 e associadas a ambiente com substratos lignocelulósicos, tais como, Clostridium sp., Klebsiella sp. e Raoultella sp., além de consumidoras de H2 Clostridium sp., por homoacetogênese e Desulfovibrio sp. por sulfetogênese. A partir das análises dos resultados, foi possível afirmar que houve produção biológica de hidrogênio a partir de celulose como substrato e lodo de ETE industrial como inóculo. / Batch assays in anaerobic reactors were conducted to evaluate the biological production of hydrogen from different concentrations of cellulose ( E1: 2.0 g.L-1; E2: 5.0 g.L-1 and E3: 10.0 g.L-1) in initial pH of 6.8 at 37 ° C. The aim of this study was analize the sludge of a treatment plant of pulp and paper industry wastewater as inoculum in the anaerobic reactors. The assays were monitored for 16 days by analyses of total soluble carbohydrates, COD, pH, TS, TVS, biogas and organic acids and alcohols. Phylogenetic characterization was carried out for microrganisms of the Bacteria Domain by cloning and sequencing analysis. The hydrogen production was detected on the fourth day of the incubation for the three experimental conditions, probably due to the period required for cellulose hydrolysis. Hydrogen production data were adjusted to the modified Gompertz model, and the maximum hydrogen production potential (P) were 1.23 mmol for E1, 3.14 mmol for E2 and 2.33 mmol for E3. Similar hydrogen yields were observed for assays E1 and E2; ie 0.62 mmol H2.g-1 of cellulose. For E3 the yield was 0.23 mmol H2.g-1 cellulose. Butyric acid was the major organic acid observed with 2.2, 1.8 and 2.2 g.L-1 to E1, E2 and E3, respectively. Hydrogen depletion in the biogas was accompanied by the evolution of methane, acetic acid and sulfide in the three tests. By means of microscopic visualization of microrganisms samples it was possible to determine the presence of a variety of bacterial shapes and confirming the heterogeneity of the inoculum. Regarding phylogenetic analysis, there were identified, with more than 95% similarity, genera of bacteria known as hydrogen producers or related with environments associated with lignocellulosic substrates such as Clostridium sp. Klebsiella sp. and Raoultella sp., consuming genere were also detedted, such Clostridium sp. by homoacetogênese and Desulfovibrio sp. by sulfidogenesis.