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<p>Sex steroids are critical for the post-natal development of the female reproductive system, and are involved in ovulatory cycling and pregnancy. In mice, <em>Mus musculus</em>, female development, cycling, and pregnancy can be affected by the urine of conspecifics, which is known to contain active steroids. Specifically, puberty can be accelerated (the Vandenbergh effect), estrous cycling can be prolonged (the Lee-Boot effect) or synchronized (the Whitten effect), and blastocyst implantation can be disrupted (the Bruce effect). Since steroids alone can affect females in ways that are indistinguishable from these social reproductive effects, I hypothesized that urinary steroids of conspecifics may be absorbed by females, arrive in the reproductive system, and thereby affect females through known mechanisms. First I showed that tritium-labelled 17β-estradiol (³H-E₂) injected into males is excreted in their urine, and that application of urine from these males to the nose of an inseminated female results in detectable levels in her uterus. When I paired inseminated females with non-sire males injected with ³H-E₂, radioactivity was detected in the brain and reproductive tissues of the females. This was the first demonstration of steroids from one animal directly entering the body of another. Similar results were found when I exposed juvenile females to adult males injected with ³H-E₂, and when I exposed nulliparous adult females to same-strain ³H‑E₂- or ³H-progesterone- (³H-P₄) treated adult males or females. Taken with the existing literature, these results suggest that steroid transfer may underlie various social reproductive phenomena in mice, with potential implications for many other species.</p> / Doctor of Philosophy (PhD)

La tuberculose est une maladie infectieuse extrêmement contagieuse qui dans sa forme simple peut être soignée et guérie. Cependant, des formes multirésistantes aux traitements classiques ont récemment fait leur apparition et le développement de nouvelles molécules constitue donc un enjeu majeur de santé publique. Le 3,3-diméthyl-1,2-dihydro-3H-benzofuro[3,2-f][1]benzopyrane est un produit possédant une activité antituberculeuse marquée, y compris sur des lignées résistantes. L’objectif des travaux réalisés ici est la recherche de composés de puissance accrue et l’élucidation du mécanisme d’action de cette série. Dans une première partie, des modifications structurales portant sur le cycle A sont présentées. Les résultats des tests biologiques ont permis de sélectionner des composés qui possèdent un index de sélectivité favorable entre l’activité antituberculeuse et la toxicité. Un composé de structure linéaire a également montré un profil d’activité intéressant. Les études de mécanisme d’action ont mis en évidence que les composés synthétisés affectent les synthèses des époxy-mycolates ainsi que celle des α-mycolates de la paroi cellulaire. Dans une deuxième partie l’influence des groupements en position 3 du 3,3-diméthyl-1,2-dihydro-3H-benzofuro[3,2-f][1]benzopyrane a été étudiée. Des composés possédants des chaines de longueur croissante en cette position ont été synthétisés. L’activité antituberculeuse des premiers produits obtenus, a été mesurée et a montré une importante influence du type de chaine introduit sur l’activité biologique. Les études présentées dans ce travail ont donc permis d’une part de préciser la cible cellulaire de ces molécules et d’autre part de sélectionner des composés peu cytotoxiques. / Tuberculosis is a highly contagious infectious disease which can be treated and cured in its simple form. However, multidrug resistant forms towards classic treatments have recently appeared and the development of new drugs is a major challenge for public health. The 3,3-dimethyl-1,2-dihydro-3H-benzofuro[3,2-f][1]benzopyran have a significant anti-TB activity, including resistant lines. The goal of this work is the research of more active compounds and the elucidation of the mechanism of action of this series. In a first part, modifications are introduced on A ring. The results of biological tests were permitted to select compounds that have a favorable selectivity index between tuberculosis activity and toxicity. A linear compound has also showed an interesting activity. Studies on mycolates biosynthesis revealed that the synthesized compounds affect the synthesis of epoxy-mycolates and α-mycolates of the cell wall. In the second part of this work the influence of groups introduced at position 3 of 3,3-dimethyl-1 ,2-dihydro-3H-benzofuro[3,2-f][1]benzopyran was studied. Compounds possessing different length chains at this position have been synthesized. Anti-TB activity of the first products obtained was measured and showed a significant influence of the type of chain introduced. The studies presented in this work permitted to define the cellular target of these compounds and on the other hand to select the compounds with lowest cytotoxicity.

Made available in DSpace on 2015-07-22T20:50:10Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-26. Added 1 bitstream(s) on 2015-08-11T03:25:54Z : No. of bitstreams: 1 Publico-11764a.pdf: 1760987 bytes, checksum: 26371946d909a5525c0bd6c7cc6d7c33 (MD5). Added 1 bitstream(s) on 2015-08-11T03:25:55Z : No. of bitstreams: 2 Publico-11764a.pdf: 1760987 bytes, checksum: 26371946d909a5525c0bd6c7cc6d7c33 (MD5) Publico-11764b.pdf: 969495 bytes, checksum: d87ae7194b036aaff67581e32d434f64 (MD5) / Objetivo: Verificar se indivíduos susceptíveis e não-susceptíveis às convulsões clônicas induzidas pelo DMCM, um agonista inverso benzodiazepínico, diferem: 1) na sensibilidade ao efeito hipnótico induzido pelo diazepam e por outros moduladores alostéricos positivos do receptor GABAA; 2) na marcação auto-radiográfica com o [3H]- flunitrazepam ao longo do encéfalo; 3) na marcação de [3H]-L-glutamato e do [3H]-MK 801 em membranas de regiões encefálicas; e 4) na atividade da enzima Na+/K+- ATPase, bem como na marcação da [3H]-ouabaína às isoenzimas Na+/K+- ATPase de alta e de baixa afinidade ao radioligante em membranas de regiões encefálicas. Métodos: Ratos Wistar, machos, adultos foram administrados intraperitonealmente duas vezes com uma DC50 de DMCM (com intervalo de uma semana entre as administrações), obtendo-se dois grupos distintos: o grupo susceptível às convulsões (SC), que apresentou convulsões clônicas em ambas as exposições à droga, e o grupo não-susceptível às convulsões (NSC), que não apresentou alterações motoras em ambas as exposições. Após cerca de 25 dias da segunda administração de DMCM, os grupos selecionados foram submetidos aos experimentos com os hipnóticos diazepam, pentobarbital e etanol, nos quais foram registrados o tempo e a latência de sono ou foram sacrificados e seus encéfalos retirados para os seguintes ensaios bioquímicos: 1) auto-radiografia com o [3H]-flunitrazepam; 2) marcação de [3H]-L-glutamato e de [3H]- MK 801 em membranas neuronais; e 3) atividade enzimática da Na+/K+- ATPase e marcação de [3H]-ouabaína em enzimas de alta e baixa afinidade em membranas neuronais. Resultados: O grupo SC apresentou menor tempo de sono induzido pelo diazepam com relação ao grupo NSC, embora não tenham se distinguindo no tempo de sono induzido pelo pentobarbital e pelo etanol. Com relação aos experimentos bioquímicos, observou-se uma menor marcação de [3H]-flunitrazepam na região CA2 ventral do hipocampo no grupo SC. Quanto à ligação de [3H]-L-glutamato foi menor no grupo SC nas regiões do córtex frontal, amígdala + córtex límbico e hipocampo, enquanto que a ligação de [3H]-MK 801 foi menor no córtex frontal, hipocampo e estriado. Embora os grupos não tenham se diferenciado na atividade enzimática da Na+/K+- ATPase, o grupo SC apresentou uma menor marcação da [3H]-ouabaína em isoenzimas de alta afinidade nas regiões do tronco encefálico, córtex frontal e hipocampo, bem como uma menor marcação de [3H]-ouabaína nas regiões do tronco encefálico e córtex frontal em isoenzimas de baixa afinidade. Conclusão: As diferenças entre os grupos quanto à sensibilidade ao efeito convulsivante do DMCM, à ansiedade observada em experimentos anteriores, bem como à sensibilidade ao efeito hipnótico do diazepam podem estar associadas a uma diferença nos sítios benzodiazepínicos da região CA2 ventral do hipocampo, na ix atividade glutamatérgica e em isoformas específicas da Na+/K+- ATPase em determinadas regiões encefálicas. / Objective: The aim of this work was to verify if rats susceptible and non-susceptible to clonic convulsions induced by DMCM, a benzodiazepine inverse agonist, differ: 1) in the sensitivity to the hypnotic effect induced by diazepam and by others positive allosteric modulators of GABAA receptors; 2) in auto-radiographical analysis of [3H]-flunitrazepam binding along the brain; 3) in the binding of [3H]-L-glutamate and of [3H]-MK 801 in membranes from discrete brain regions; and 4) in the Na+/K+-ATPase activity, as well as in the binding of [3H]-ouabain to Na+/K+-ATPase isoenzimes with high and low affinity to the radioligand in membranes from discrete brain regions. Methods: Adult, male, Wistar rats were administered with two intraperitoneal injections of a convulsant dose 50% (CD50) of DMCM (one-week interval between them), resulting in two distinct groups: the group susceptible to clonic convulsions (SC), which presented clonic convulsions in both the expositions to the drug, and the group nonsusceptible to clonic convulsions (NSC), which did not present any motor disturbance in both the expositions. After 25 days from the second exposition to DMCM, the selected groups were submitted to the experiments with the hypnotics diazepam, pentobarbital and ethanol, in which were registered the latency and the time of sleep or they were sacrified and their brains were removed to carry out the following assays: 1) autoradiography with [3H]-flunitrazepam; 2) binding with the [3H]-L-glutamate and with the [3H]-MK 801 in neuronal membranes; 3) enzymatic activity of Na+/K+-ATPase and binding of [3H]-ouabain to the isoenzimes with high and low affinity in neuronal membranes. Results: The SC group presented a lower sleeping time induced by diazepam compared to the NSC group, and did not differ in the sleeping time induced by pentobarbital and ethanol. Concearning the biochemical experiments, it was observed a lower binding of [3H]-flunitrazepam in the CA2 subregion of ventral hippocampus in the SC group. A lower binding of [3H]-L-glutamate was also observed in the SC group in the frontal cortex, amygdala plus limbic cortex and hippocampus, whereas the binding of [3H]-MK 801 was lower in the frontal cortex, hippocampus and striatum compared to the NSC group. Althougt the groups did not differ in the enzymatic activity of Na+/K+- ATPase, the SC group presented a lower binding of [3H]-ouabain to the high-affinity isoenzimes in the brainstem, frontal cortex and hippocampus, as well as a lower binding of [3H]-ouabain to the low-affinity isoenzimes in the brainstem and in the frontal cortex compared to the NSC group. Conclusion: The differences between the groups concerning the sensitivity to the convulsant effect of DMCM, the level of anxiety previously observed, as well as the sensitivity to the hypnotic effect of diazepam may be associated with the GABAA/benzodiazepine site in CA2 subregion of ventral hippocampus, with glutamatergic activity and with specific isoforms of Na+/K+-ATPase in rat brain regions. / TEDE / BV UNIFESP: Teses e dissertações

This thesis deals with the influence of the discharges of the Dukovany Nuclear Power Plant ("Dukovany NPP") and the assessment of impacts on the population and the vicinity of the power plant. The thesis summarizes the issues of tritium 3H discharges into waterways and partially deals with the 14C discharges. Attention is paid especially to the radioisotope of hydrogen 3H, due to its chemical and physical form and its presence in the cooling medium (light water) used by that type of nuclear power reactor. The thesis also contains a description of the current state of the Dukovany NPP, especially the existing discharges of the radioactive substances to the surroundings of the nuclear power plant, both to the air and into the waterway. Also was discussed the issue of the new planned blocks of the Dukovany NPP and impacts of the projected discharges on the population during the simultaneous operation of the existing blocks and the planned blocks, again in relation to the 3H discharged into the waterway. The application ESTE AI was used for the determination of individual groups of inhabitants who are most exposed to the radioactive discharges (also called representative person). Based on the current discharges of the Dukovany NPP and the planned blocks discharges were determined the annual effective doses for a representative person. The doses were compared with the legislation on the conditions for the peaceful use of nuclear energy requirements and then with the water management legislation. In order to avoid exceeding these limits were set up recommendations how to dispose of radioactive substances optimally. The thesis answer to the research question: What impacts on the population will have discharges of the Dukovany NPP after the construction of a new nuclear source, especially in relation to the discharges of the 3H into the waterway and which measures will must be applied on the optimization of the inhabitants doses.

Numerous previous studies of GABAAR ligands have suggested that GABAAR agonists must be zwitterionic and feature an intercharge separation similar to that of GABA (approx. 4.7-6.0 Ã ). We have demonstrated that monomeric, homodimeric and heterodimeric non-zwitterionic GABA amides are partial, full, or superagonists at the murine GABAA receptor (GABAAR). The agonism of these GABA amides is comparable to that of THIP, as shown by in vitro assay results. The assay data indicate that the agonism of GABA amides is tether length-dependent. Optimum agonism is achieved with a tether length of four methylenes in GABA amide dimers and in GABA amides bearing pendant amide or amino groups. We have further investigated the structure-activity relationship for GABA amides on the GABAAR by performing structural modifications to both the superagonist 2c and the agonist 6c. Synergism and [3H]muscimol binding experiments show that 2c binds to the same sites as GABA. Structural modification of 2c demonstrated that partial rigidification of the tether eliminated agonism and caused ligands to behave as weak competitive antagonists. We have also investigated the agonism of four ZAPA derivatives in 36Cl- uptake functional assay. Two of them are found to be as potent as GABA. In our studies of 1,4-benzodiazepines, our goal was to synthesize three different subtypes of quaternary 1,4-benzodiazepines by use of the memory of chirality (MOC) strategy. Disappointingly, most of the deprotonation/alkylations failed, due to various reasons. The failure of the reactions of (S)-alanine-derived tetrahydro-1,4-benzodiazepin-3-ones was probably due to either the unexpected side reactions or the steric hindrance of enolate alkylation. In the case of tetrahydro-1,4-benzodiazepin-2-ones, computational studies suggested that steric hindrance by both the benzo ring and N4-allyl group might retard deprotonation at C3 by bulky bases like KHMDS or LDA. Finally, (S)-serine-derived 1,4-benzodiazepin-2-ones and their elimination products (ï ¡-methylene benzodiazepines) were prepared. These proved unreactive towards deprotonation/alkylations and conjugate additions, respectively. The low reactivity of the ï ¡-methylene benzodiazepines towards nucleophiles was attributed to highly delocalized LUMOs that failed to direct nucleophiles to the ï ¢-carbons. / Ph. D.

3,5-Dibromo-2-aminobenzamide was reacted with 1,3-cyclohexanedione derivatives in the presence of iodine as catalyst in toluene under reflux to afford novel 6,8-dibromo-2-[3-(2´-alkyl-1´,2´,3´,4´-tetrahydro-6´,8´-dibromo-4´-oxoquinazoline-2yl)propyl]quinazolin-4(3H)-ones in high yields. Suzuki-Miyaura cross-coupling of the latter with arylboronic acids in the presence of Pd(PPh3)2Cl2–Xphos catalyst complex and K2CO3 as a base in dioxane-water mixture (3:1, v/v) afforded the corresponding polyaryl-substituted bis-heterocycles in a single step operation. The resultant compounds were characterized using a combination of NMR (1H and 13C) and IR spectroscopic techniques, as well as mass spectrometry. The electronic absorption and emission properties of these polyaryl-substituted bis-heterocycles comprising 2,3-dihydroquinazolin-4(1H)-one and quinazolin-4(3H)-one moieties linked by a flexible carbon chain were measured in dimethylsulfoxide (DMSO) and acetic acid by means of UV-Vis and fluorescence spectroscopic techniques. The absorption spectra of the resultant polyaryl-substituted bis-heterocycles showed blue-shift in acetic acid and red-shift in DMSO, while their emission spectra are blue-shifted in DMSO and red-shifted in acetic acid. The 4-methoxy groups on aryl-substituents caused red shift on π‒π* transition of the aryl-substituents. Moreover, it was also observed that as the propyl linkage becomes more substituted, the absorption and emission intensities decrease. / Chemistry / M. Sc. (Chemistry)

-5- ABSTRACT A huge effort has been put in determining the mechanism of the development of tolerance and dependence in context of clinical use of morphine for treatment of severe pain. Understanding of this mechanism would help to design new and more efficient pharmaceuticals. This diploma paper discus the opiate receptors with a special focus on long-term effect of chronic morphine treatment, which was determined using a radioligand binding assays with a non-selective antagonist [3 H]Diprenorphine. One of the goals of this work was to create and optimise a method for preparation of pure plasma membranes from rat cortex using percoll gradient. There were five groups, which differed in the length of morphine treatment: ten days (M-10), twenty-eight days (M-28), ten days with seven days of regression (RM-10 twenty-eight days with seven days of regression (RM-28) and a control group (K). The loss of total opioid receptor number was noticeable after ten days and grew slightly during continuous morphine treatment and kept lowering in the period of regression. The total loss was approximately 30% of the control binding. The equilibrium dissociation constant (Kd), thus the affinity of [3 H]Diprenorphine wasn't significantly different among the groups. Morphine acts through µ-opioid receptor, that's why there was a...

3,5-Dibromo-2-aminobenzamide was reacted with 1,3-cyclohexanedione derivatives in the presence of iodine as catalyst in toluene under reflux to afford novel 6,8-dibromo-2-[3-(2´-alkyl-1´,2´,3´,4´-tetrahydro-6´,8´-dibromo-4´-oxoquinazoline-2yl)propyl]quinazolin-4(3H)-ones in high yields. Suzuki-Miyaura cross-coupling of the latter with arylboronic acids in the presence of Pd(PPh3)2Cl2–Xphos catalyst complex and K2CO3 as a base in dioxane-water mixture (3:1, v/v) afforded the corresponding polyaryl-substituted bis-heterocycles in a single step operation. The resultant compounds were characterized using a combination of NMR (1H and 13C) and IR spectroscopic techniques, as well as mass spectrometry. The electronic absorption and emission properties of these polyaryl-substituted bis-heterocycles comprising 2,3-dihydroquinazolin-4(1H)-one and quinazolin-4(3H)-one moieties linked by a flexible carbon chain were measured in dimethylsulfoxide (DMSO) and acetic acid by means of UV-Vis and fluorescence spectroscopic techniques. The absorption spectra of the resultant polyaryl-substituted bis-heterocycles showed blue-shift in acetic acid and red-shift in DMSO, while their emission spectra are blue-shifted in DMSO and red-shifted in acetic acid. The 4-methoxy groups on aryl-substituents caused red shift on π‒π* transition of the aryl-substituents. Moreover, it was also observed that as the propyl linkage becomes more substituted, the absorption and emission intensities decrease. / Chemistry / M. Sc. (Chemistry)