Disinfection and environmental studies on pathogenic free-living amoebae : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Microbiology at Massey University

Over the last fifteen years, there has been an increasing awareness of sporadic cases of Primary Amoebic Meningoencephalitis (PAM), affecting primarily younger age groups and appearing in an acute fulminant form. The earliest positive case known, may have been in England in 1909. The pathogenic free-living amoebae (PFLA), which comprises the genera Naegleria and Acanthamoeba, are the causative organisms of PAM and Granulomatous Amoebic Encephalitis (GAE) respectively. PAM is a rapidly fatal disease affecting the central nervous system (CNS), and GAE although essentially confined to the CNS, may also take the form of granulomata in the liver, spleen, uterus and kidneys. A study on the disinfecting potential of Baquacil in axenic conditions, for comparison with the disinfecting potential of the chlorine, chlorine dioxide, ozone and Deciquam 222, showed that the order of effectiveness as amoebicides was Baquacil, chlorine, chlorine dioxide, ozone and Deciquam 222 in hard water. In soft water the order is Deciquam 222, Baquacil, chlorine, chlorine dioxide and ozone. Further study on the effect of Baquacil, chlorine and chlorine dioxide on amoebae, in conditions involving the use of a known Biochemical Oxygen Demand (BOD), a known bacteria concentration, and a combination of BOD and bacteria, confirmed Baquacil as a more effective amoebicide than chlorine, which in turn was more effective than chlorine dioxide. The concentrations of each disinfectant required were increased by the presence of a BOD, and of bacteria. The bacteria were preferentially destroyed over the amoebae with all three disinfectants. Baquacil resistant clones of Naegleria fowleri were isolated, although it is not known whether this resistance is due to genetic or physiological variation. Axenically and Monoxenically cultured amoebae were used, the latter to increase the resemblance of the amoebae to those found in the environment. Differences in survival rates were observed, the monoxenically cultured amoebae invariably having higher survival rates. Competition studies were done with Naegleria spp. and T.pyriformis on three bacteria species, after preliminary studies on the ability of the two protozoa to grow on eight species of bacteria. Of the three bacteria used in the competiton studies, Escherichia coli and Enterobacter cloacae were shown to support both Naegleria spp. and T.pyriformis, with the ciliate increasing in numbers by up to 3 fold over the controls, but the amoebae were affected only slightly, with a small decrease in numbers compared to the controls. A synergistic relationship was evident on the third bacteria species, Pseudomonas fluorescens, between Naegleria spp. and T.pyriformis, where as in the controls, this bacterium was not a good growth support bacteria for either protozoan

Shedding Light on the Matter of Abell 781

The galaxy cluster Abell 781 West has been viewed as a challenge to weak gravitational lensing mass calibration, as Cook and dell'Antonio (2012) found that the weak lensing signal-to-noise in three independent sets of observations was consistently lower than expected from mass models based on X-ray and dynamical measurements. We correct some errors in statistical inference in Cook and dell'Antonio (2012) and show that their own results agree well with the dynamical mass and exhibit at most 2.2--2.9$\sigma$ low compared to the X-ray mass, similar to the tension between the dynamical and X-ray masses. Replacing their simple magnitude cut with weights based on source photometric redshifts eliminates the tension between lensing and X-ray masses; in this case the weak lensing mass estimate is actually higher than, but still in agreement with, the dynamical estimate. A comparison of lensing analyses with and without photometric redshifts shows that a 1--2$\sigma$ chance alignment of low-redshift sources lowers the signal-to-noise observed by all previous studies which used magnitude cuts rather than photometric redshifts. The fluctuation is unexceptional, but appeared to be highly significant in Cook and dell'Antonio (2012) due to the errors in statistical interpretation.Comment: 7 pages, submitted to MNRA

Optical Galaxy Clusters in the Deep Lens Survey

We present the first sample of 882 optically selected galaxy clusters in the Deep Lens Survey (DLS), selected with the Bayesian Cluster Finder. We create mock DLS data to assess completeness and purity rates, and find that both are at least $70\%$ within 0.1$\le z \le$ 1.2 for clusters with $M_{200}\ge 1.2\times 10^{14}M_{\odot}$. We verified the integrity of the sample by performing several comparisons with other optical, weak lensing, X-ray and spectroscopic surveys which overlap the DLS footprint: the estimated redshifts are consistent with the spectroscopic redshifts of known clusters (for $z>0.25$ where saturation in the DLS is not an issue); our richness estimates in combination with a previously calibrated richness-mass relation yields individual cluster mass estimates consistent with available SHeLS dynamical mass estimates; synthetic mass maps made from the optical mass estimates are correlated ($>3\sigma$ significance) with the weak lensing mass maps; and the mass function thus derived is consistent with theoretical predictions for the CDM scenario. With the verified sample we investigated correlations between the brightest cluster galaxies (BCG) properties and the host cluster properties within a broader range in redshift (0.25 $\le z \le$ 0.8) and mass ($\ge2.4\times 10^{14}M_{\odot}$) than in previous work. We find that the slope of the BCG magnitude-redshift relation throughout this redshift range is consistent with that found at lower redshifts. This result supports an extrapolation to higher redshift of passive evolution of the BCG within the hierarchical scenario.Comment: Paper accepted for publication in MNRAS, Table 1 will be available online or under reques

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An Examination of Synthetic Routes to Papaverine, and, Synthetic Studies in 1:4 Oxazine Chemistry

Part I - An Examination of Synthetic Routes to Papaverine. In an attempt to establish a new synthesis of the alkaloid papaverine, four possible routes were examined. 3:4-Dimethoxyphenylacetyl chloride was condensed with ethyl aminoacetate giving ethyl 3:4-dimethoxyphenylacetamido-acetate, which on hydrolysis formed the free acid. Condensation of this acid and 3:4-dimethoxybenzaldehyde led to the formation of 2-(3:4-dimethoxybenzyl)-4-(3:4-dimethoxybenzal)-oxazol-5-one which underwent ring opening with sodium carbonate to alpha-(3:4-dimethoxyphenylacetamido)-3:4-dimethoxy-cinnamic acid. Decarboxylation of the acid gave beta-(3:4-dimethoxyphenylacetamido)-3:4-dimethoxystyrene (I). The structure of this material was confirmed by hydrogenation to homoveratroyl-homoveratrylamine. All attempts to ring close this substance with the elimination of the elements of water to papaverine failed. The theoretical aspects of this failure are discussed. Using opianic acid, a possible synthetic route was investigated. The acid condensed with nitromethane giving nitromethyhmeconin, reduction of which formed aminomethyl-meconin hydrochloride. Acylation with 3:4-dimethoxyphenyl-acetyl chloride led to the formation of the desired 3:4-dimethoxyphenylacetamido-methylmeconin (II). It was however found impossible to eliminate the lactone ring and convert this compound either to papaverine or an isoquinoline derivative. An examination of the ring closure of 2-(alpha-bromophenyl-acetamido)-l-phenyl-ethane (III) was made in the hope that during this reaction the excess hydrogen atoms of the heterocyclic ring formed, would be removed by reductive dehalogenation. Instead of the expected product, 1-benzyl-isoquinoline however, 1-benzyl-3:4-dihydroisoquinoline was produced. When the reaction was examined using 2-(alpha-chloro-3:4-dimethoxyphenylacetamido)-1-(3:4-dimethoxy-phenyl)-ethane, no evidence of reductive dehalogenation was found. An approach to a papaverine synthesis was made through dihomoveratramide (IV) by treatment of this substance with phosphorus oxychloride to form 3-chloro papaverine. The diamide was found to be unstable to the action of this reagent and gave homoveratramide. An alternative synthesis of 3-hydroxy-isoquinolines was established. Methyl 2-acetyl-4:5-dimethoxyphenylacetate with ammonia gave 6:7-dimethoxy-3-hydroxy-1-methyl-isoquinoline and similarily methyl 2-benzoyl-4:5-dimethoxyphenylacetate formed 6:7-dimethoxy-3-hydroxy-1-phenyl-isoquinoline. When the reaction was examined using methyl 4:5-dimethoxy-2-phenylacetyl-phenylacetate, the product isolated was 6:7-dimethoxy-2-hydroxy-3-phenyl-1:4-naphthoquinone. Methyl 4:5-dimethoxy-2- (3: 4-dimethoxyphenylacetyl) -phenylacetate also formed 6:7-dimethoxy-3-( 3:4-dimethoxyphenyl)-2-hydroxy -1:4-naphthoquionoe. In conjunction with this work, the Schiff's base formed by the condensation of 2-(3:4-dimethoxyphenyl)-2- methoxy-ethylamine and 3:4-dimethoxybenzaldehyde was shown to rearrange giving 1:2-dihydro-6:7-dimethoxy-l-(3:4-dimeth- oxyphenyl) -isoquinoline. Part II - Synthetic Studies in 1:4-Oxazine Chemistry In an extension of the synthetic route to 5-hydroxy-l:4-oxazines discovered by Newbold, Spring and Sweeny (J. 1950, 909. ), the synthesis of phenyl substituted 5-hydroxy-1:4-oxazines was successfully carried out by this method. At the same time various condensations of difunctional compounds to 1:4-oxazines were examined. Bromoacetal was condensed with ethanolamine forming 2-amino-ethoxy-acetaldehyde diethylacetal which was converted into dihydro-1:4-oxazine. 2-Amino-1-hydroxy-propane in a similar manner gave (2-amino-1-methyl-ethoxy)-acetaldehyde diethylacetal which was converted to 2-methyl-dihydro-1:4-oxazine. The extension of this reaction to fully unsaturated l:4-oxazines was examined

Extensions of Normed Algebras

We review and analyse techniques from the literature for extending a normed algebra, A to a normed algebra, B, so that B has interesting or desirable properties which A may lack. For example, B might include roots of monic polynomials over A. These techniques have been important historically for constructing examples in the theory of Banach algebras. We construct new examples in this way. Elsewhere we contribute to the related programme of determining which properties of an algebra are shared by certain extensions of it. Similarly, we consider the relations between the topological spaces, M(A) and M(B), of closed, maximal ideals of A and B respectively. For example, it is shown that if B is one of the types of 'algebraic extensions' of A constructed in the thesis and M(B) has trivial first Cech-cohomology group then so has M(A). The invertible group of a normed algebra is studied in Chapter 4; it is shown that if a Banach algebra, A, has dense invertible group then so has every integral extension of A. The context for this work is also explained: some new results characterising trivial uniform algebras by means of approximation by invertible elements are given. We show how these results partially answer a famous, open problem of Gelfand. Results in Chapter 4 lead to the conjecture that a uniform algebra is trivial if the group of exponentials of its elements is dense in the algebra. We investigate this conjecture in Chapter 5. In the search for a counterexample, we construct and establish some properties of `logarithmic extensions' of a regular uniform algebra.Comment: Ph.D. Thesis, University of Nottingham, 2003. 76 pages; plain Te