A clear and predictive understanding of the propensity for crystallisation of one polymorph over another is lacking, and in this regard glycine is a model system due to difficulties in crystallisation of the thermodynamically stable gamma polymorph. The preferential crystallisation of gamma-glycine in the presence of micellar CTAB (Cetyltrimethylammonium bromide) as opposed to the alpha form commonly crystallised from pure solution was observed. A rationale for this result was sought through the observation of the nucleation and growth kinetics of the alpha and gamma polymorphs of glycine (and DL-alanine) using in situ microscopy, the measurement of induction times and following the solution mediated phase transformation of alpha-glycine. These observations help explain the dominant crystal form produced in a number of solutions. The nucleation and growth rates of alpha-glycine were shown to be orders of magnitude greater than those of gamma-glycine in pure solution. Also, the addition of a cationic surfactant (such as CTAB) or modification of the solution pH were shown to dramatically accelerate the nucleation and growth of polar gamma-glycine and DL-alanine, a rarely reported phenomenon. In addition, the growing (00-1) faces of gamma-glycine and DL-alanine, at which growth was accelerated, were shown to be macroscopically rough, indicating a growth mechanism dominated by nucleation rather than the growth of layers. The most likely cause of the inhibited kinetics of gamma-glycine and DL-alanine is water bound electrostatically at the negatively charged (00-1) faces, while the growth acceleration inferred by the additives is related to their ability to release water from these surfaces. Other mechanisms which may play a role include the adsorption of adventitious impurities, strong electrostatic repulsion between like-charged carboxylate groups at the (00-1) surface resulting in structural disorder, and the effect of surface energy on the rate of surface nucleation. This research provides an important example of nature’s complexity in selecting crystal form in polymorphic systems, gives further insight into the causes of the asymmetric growth of polar crystal structures, and introduces the possibility that the crystallisation kinetics of ‘difficult’ slow growing compounds may sometimes be modified through the use of additives.

Aflatoxin is a highly carcinogenic secondary metabolite produced by Aspergillus flavus contributing to significant loss of corn production. There are several breeding techniques to make the corn resistant to aflatoxin accumulation with the genotype having desirable characters. Corn- resistant inbred line Mp313E provides resistance against A. flavus. Near-isogenic lines containing QTLs were developed by backcrossing Mp313E (resistant parent) and Va35 (susceptible parent). WRKY transcription factors play an important role in the growth and development of plants. Searching DNA markers associated with these WRKY genes is a considerable approach for the plant breeders. In this study, PCR and agarose gel electrophoresis methods were used to determine the polymorphic WRKY gene DNA markers associated with aflatoxin reduction quantitative trait loci in maize. The analysis revealed 26 polymorphic maize WRKY genes. Computational 3D models of these WRKY genes were predicted. Virtual 2D plot was made for these WRKY proteins to determine their position.

No / Pure anhydrous polymorphs of carbamazepine were prepared by solution-enhanced dispersion with supercritical fluids (SEDSTM). Crystallization of the polymorphs was studied. Mechanisms are proposed that consider the thermodynamics of carbamazepine, supersaturation in the SEDSTM process, and the binary phase equilibria of organic solvents and the carbon dioxide antisolvent. -Carbamazepine was crystallized at high supersaturations and low temperatures, -carbamazepine crystallized from a methanol-carbon dioxide phase split, and -carbamazepine crystallized via nucleation at high temperatures and low supersaturation.

No / The predicted stability differences of the conformational polymorphs of oxalyl dihydrazide and ortho-acetamidobenzamide are unrealistically large when the modeling of intermolecular energies is solely based on the isolated-molecule charge density, neglecting charge density polarization. Ab initio calculated crystal electron densities showed qualitative differences depending on the spatial arrangement of molecules in the lattice with the greatest variations observed for polymorphs that differ in the extent of inter- and intramolecular hydrogen bonding. We show that accounting for induction dramatically alters the calculated stability order of the polymorphs and reduces their predicted stability differences to be in better agreement with experiment. Given the challenges in modeling conformational polymorphs with marked differences in hydrogen bonding geometries, we performed an extensive periodic density functional study with a range of exchange-correlation functionals using both atomic and plane wave basis sets. Although such electronic structure methods model the electrostatic and polarization contributions well, the underestimation of dispersion interactions by current exchange-correlation functionals limits their applicability. The use of an empirical dispersion-corrected density functional method consistently reduces the structural deviations between the experimental and energy minimized crystal structures and achieves plausible stability differences. Thus, we have established which types of models may give worthwhile relative energies for crystal structures and other condensed phases of flexible molecules with intra- and intermolecular hydrogen bonding capabilities, advancing the possibility of simulation studies on polymorphic pharmaceuticals.

No / Despite a tendency to undergo solution-mediated polymorphic transformation, the dissolution behaviour of the metastable FI (triclinic) polymorph of the pharmaceutical compound carbamazepine (CBZ) was investigated using in situ optical microscopy. Experiments were performed at an undersaturation where single crystals of the metastable FI polymorph dissolved. Dissolution in different solvents was investigated at a constant undersaturation. Separately the sublimation of FI was examined and additionally the dissolution was observed at undersaturations where the more stable FIII polymorph crystallized. The results show that both the dissolution and sublimation of FI occur primarily in the direction of the a-axis of the FI crystal structure where the CBZ molecules are found to stack in this direction. The order for the dissolution rate of FI was acetonitrile ≥ methanol > ethanol. The order of the dissolution rates in each of the solvents is inversely correlated to the viscosity and the binding energy of the solvents with the (100) surface of FI in each of the solvents. This suggests that the rate determining step for the dissolution may be either the diffusion or the detachment of CBZ molecules from the surface of FI. A notable difference in dissolution behaviour is also observed at undersaturations where the more stable FIII polymorph nucleates and grows. / SFI

Yes / Polymorphism, crystal shape and solubility of 1,4-dihydroxyanthraquinone (quinizarin) have been investigated in acetic acid, acetone, acetonitrile, n-butanol and toluene. The solubility of FI and FII from 20 °C to 45 °C has been determined by a gravimetric method. By slow evaporation, pure FI was obtained from n-butanol and toluene, pure FII was obtained from acetone, while either a mixture of the two forms or pure FI was obtained from acetic acid and acetonitrile. Slurry conversion experiments have established an enantiotropic relationship between the two polymorphs and that the commercially available FI is actually a metastable polymorph of quinizarin under ambient conditions. However, in the absence of FII, FI is kinetically stable for many days over the temperature range and in the solvents investigated. FI and FII have been characterized by infrared spectroscopy (IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), transmission and ordinary powder X-ray diffraction (PXRD) at different temperatures. The crystal structure of FII has been determined by single-crystal XRD. DSC and high-temperature PXRD have shown that both FI and FII will transform into a not previously reported high-temperature form (FIII) around 185 °C before this form melts at 200–202 °C. By indexing FIII PXRD data, a triclinic P[1 with combining macron] cell was assigned to FIII. The solubility of quinizarin FI and FII in the pure organic solvents used in the present work is below 2.5% by weight and decreases in the order: toluene, acetone, acetic acid, acetonitrile and n-butanol. The crystal shapes obtained in different solvents range from thin rods to flat plates or very flat leaves, with no clear principal difference observed between FI and FII. / SFI; Swedish Research Council

No / The solution-mediated polymorphic transformation from Form II to Form III 2-oxo-1-pyrrolidine acetamide (piracetam) was investigated in seven organic solvents over the temperature range of 5–50 °C. The transformation rate increased as a function of temperature, agitation, and the solubility of piracetam in the host solvent. However, this trend was reversed in 2-propanol. Molecular modeling demonstrated that 2-propanol forms interactions with piracetam molecules in solution stronger than those formed by other solvents, thereby retarding the nucleation and growth of FIII(6.525) during the transformation in this solvent. / SFI

Submitted by Suzana Dias (suzana.dias@famerp.br) on 2018-10-26T18:02:09Z No. of bitstreams: 1 MarlonFragaMattos_dissert.pdf: 1719909 bytes, checksum: 70d153012a84a6566276733a0ea859da (MD5) / Made available in DSpace on 2018-10-26T18:02:09Z (GMT). No. of bitstreams: 1 MarlonFragaMattos_dissert.pdf: 1719909 bytes, checksum: 70d153012a84a6566276733a0ea859da (MD5) Previous issue date: 2017-09-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Down syndrome (DS) is the most frequent human chromosomopathy with approximate incidence of the 1 to 850 live births, nearly 90-95% of these cases are characterized by the presence of three copies of chromosome 21 as a result of the meiotic nondisjunction. DS individuals present many clinic features, including immunological changes that result in altered inflammatory response. The immune response is modulated by pro- and anti-inflammatory cytokines whose expression could be influenced by genetic polymorphisms in the coding or promoter region within the gene. Objectives: The study aimed to evaluate the frequencies of the -174G/C, -572G/C e -597G/A polymorphisms in the interleukin (IL) 6 gene promoter region and of the -592C/A, -1082A/G e -819C/T polymorphisms in the IL-10 gene promoter region in individuals with DS, and a control group without 21 trisomy, as well as to investigate the impact of the studied genotypes in the interleukins serum levels. Material and Methods: DNA samples of 200 DS individuals and 200 controls without DS were submitted to Polymerase Chain Reaction – Restriction Fragment Length Polymorphism (PCR-RFLP) or real time PCR for evaluate to presence of the -174G>C, -572G>C, and -597G>A IL-6 and -592C>A, -1082A>G, and -819C>T IL-10 polymorphisms. The serum measurement of IL-6 and IL-10 was performed in a subgroup (54 cases and 54 controls) by ELISA essay. The genotypic distribution between groups was performed by multiple logistic regression by SNPStats, program, and the linkage disequilibrium evaluation and haplotype frequency was performed by Haploview program. The comparison of IL-6 and IL-10 serum level between the groups was performed by Mann Whitney test, the interleukins concentrations analyze in relation to genotypes was performed by Kruskal-Wallis test, using the GraphPad Prism version 6.0 software. The standard error of 5% was accept. Result: Either the frequency of IL-6 and IL-10 polymorphisms or their haplotypes did not show differences between the case and control groups. There was no association between the IL-6 and IL-10 serum levels and the IL-6 and IL-10 polymorphisms. IL-10 serum levels were increased in the case group in relation to control group. Conclusion: The frequencies of the polymorphisms and haplotypes evaluated are not different between individuals with and without DS. Genotypes show no effect on the IL-6 and IL-10 serum levels. The IL-10 serum levels are increased in DS individuals, but the IL-10 polymorphisms are not the main factors that influence in higher expression of the IL-10 in DS. / A síndrome de Down (SD) é a cromossomopatia humana mais frequente, com incidência aproximada de 1 em 850 nativivos e, em cerca de 90-95% dos casos, é atribuída à trissomia livre do cromossomo 21 resultante da não-disjunção meiótica. Os indivíduos com a síndrome apresentam várias características clínicas, incluindo alterações imunológicas que resultam em resposta inflamatória alterada. A resposta imune é modulada por citocinas pró e anti-inflamatórias cuja expressão pode ser influenciada por polimorfismos genéticos na região codificante ou promotora do gene. Objetivos: O presente estudo teve como objetivos avaliar as frequências dos polimorfismos -174G/C, -572G/C e -597G/A na região promotora do gene da interleucina (IL) 6 e dos polimorfismos -592C/A, -1082A/G e -819C/T na região promotora do gene da IL-10 em indivíduos com SD, e em um grupo controle sem a trissomia do cromossomo 21 e investigar o impacto dos genótipos estudados nos respectíveis níveis séricos das interleucinas. Materiais e Métodos: Amostras de DNA de 200 indivíduos com SD e 200 controles sem a síndrome foram submetidas à reação em cadeia da polimerase - polimorfismo no comprimento dos fragmentos de restrição (PCR-RFLP) ou PCR em tempo real para avaliação da presença dos polimorfismos IL-6 -174G/C, -572G/C e -597G/A e IL-10 -592C/A, -1082A/G e -819C/T. A dosagem sérica de IL-6 e IL-10 foi realizada em um subgrupo de indivíduos (54 casos e 54 controles) pela técnica de ELISA. A distribuição genotípica entre os grupos foi realizada por regressão logística pelo programa SNPStats, e a avaliação do desequilíbrio de ligação e frequência dos haplótipos foram realizadas pelo programa Haploview. A comparação dos níveis séricos de IL-6 e IL-10 entre os grupos foi realizada pelo teste de Mann Whitney. A análise das concentrações de interleucinas em relação aos genótipos foi realizada com o teste de Kruskal-Wallis, utilizando o software GraphPad Prism versão 6.0. O erro aceito foi de 5%. Resultado: A frequência dos polimorfismos de IL-6 e IL-10 e dos seus haplótipos não mostrou diferenças entre os grupos caso e controle. Também não houve associação entre os níveis séricos de IL-6 e IL-10 e os polimorfismos de IL-6 e IL-10. Os níveis séricos de IL-10 foram aumentados no grupo caso em relação ao grupo controle. Conclusão: As frequências dos polimorfismos e haplótipos estudados não diferem entre indivíduos com SD e sem a síndrome e os genótipos não têm efeito nos níveis séricos de IL-6 e IL-10. Os níveis de IL-10 são aumentados em indivíduos com SD, mas os polimorfismos no gene IL-10 não são os principais fatores que influenciam a expressão aumentada da IL-10 na SD.

Many factors detrimental to healthy aging have been proposed including depression, stress, cognitive decline, and telomere shortening. Of specific interest are the genetic factors that may contribute to these factors and subsequently lead to accelerated telomere shortening and aging, namely the Bcl1, 5-HT, DRD2, and ApoE polymorphisms. We sought to: 1) further clarify the role of depression, stress tolerance, and cognitive decline in aging by examining the effect of associated polymorphisms (Bcl1, 5-HT, DRD2, and ApoE) on telomere length in two samples of older adults and 2) determine the difference in absolute telomere length between the two groups. We examined two samples of older adults: participants in a competitive, athletic event (N=220; mean age=66.8 years) and a sample of community-dwelling older adults (N=208; mean age=69.1 years). Participants completed a questionnaire with demographic information and provided a saliva sample. The Bcl1, 5-HT, DRD2, and ApoE polymorphisms were determined using PCR and Taqman assays. Telomere length was determined using qPCR analysis. The community-dwelling group had significantly shorter telomere lengths than the athletic group (t=-4.82, p< .0001). Additionally, for males in the athletic group, the L/S genotype of the 5-HT polymorphism was associated with longer telomere length. In males in the community-dwelling group, the GC genotype of the Bcl1 polymorphism was associated with shorter telomere length. In females in the athletic group, the GC and GG genotypes of the Bcl1 polymorphism were associated with shorter telomere length with the opposite being true for females in the community-dwelling group: the GC genotype of the Bcl1 polymorphism predicted longer telomere length. Exercising nearly everyday and the length of exercise were associated with telomere length in both groups. Our results indicate that competitive athletic activity in older age is associated with increased telomere length, longer periods of exercise at one time may contribute to longer telomere length, and the Bcl1 and 5-HT polymorphisms are associated with telomere length in older adults.

>Magister Scientiae - MSc / Bladder grasshoppers belong to the order Orthoptera, ancient family Pneumoridae and Superfamily Pneumoroidea. This small group of grasshoppers are sound producing, nocturnal, herbivorous grasshoppers endemic to the coastal regions of southern Africa. Very little genetic work has been done on these grasshoppers, and there is some taxonomic confusion regarding the validity of some species descriptions. The aim of this study was to provide much needed clarity on the true taxonomic diversity and polymorphic attributes within the Pneumoridae, focusing on selected taxa of uncertain status. Bladder grasshoppers show distinct discontinuous polymorphism, resulting in two clearly different male morphs utilizing two different mating strategies. Primary males make use of acoustic communication for mate location. Secondary males (alternate males) are significantly smaller and employ a “sneaker” or satellite strategy where they exploit the calling between duetting couples to locate the females before the primary male. Three species of bladder grasshoppers have been described (Parabullacris vansoni, Paraphysemacris spinosus and Pneumoracris browni) that only have an alternate male morph. The validity of these species descriptions has come into question with the discovery of alternate male morphs in at least three other species (Bullacris discolor, B. membracioides and B. obliqua). Thus, the species described by Dirsh (1963) may simply be alternate males of existing species. However, to date there have been no studies looking at the genetics of alternate males, which would definitively establish whether they are conspecific with primary males.