Neural populations for maintaining body fluid balance

Fine balance between loss-of water and gain-of water is essential for maintaining body fluid homeostasis. The development of neural manipulation and mapping tools has opened up new avenues to dissect the neural circuits underlying body fluid regulation. Recent studies have identified several nodes in the brain that positively and negatively regulate thirst. The next step forward would be to elucidate how neural populations interact with each other to control drinking behavior

Neural populations for maintaining body fluid balance

Fine balance between loss-of water and gain-of water is essential for maintaining body fluid homeostasis. The development of neural manipulation and mapping tools has opened up new avenues to dissect the neural circuits underlying body fluid regulation. Recent studies have identified several nodes in the brain that positively and negatively regulate thirst. The next step forward would be to elucidate how neural populations interact with each other to control drinking behavior

Avaliação das emissões de N2O geradas por lodo granular aeróbio em reator em bateladas sequenciais para diferentes cargas orgânicas e nitrogenadas

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Ambiental, Florianópolis, 2017.Os reatores em bateladas sequenciais com grânulos aeróbios (RBSG) têm sido propostos como uma opção promissora para o tratamento biológico de efluentes domésticos e industriais, alcançando elevadas remoções de matéria orgânica e de nutrientes. No entanto, a remoção biológica de nutrientes como o nitrogênio, por meio dos processos de nitrificação e desnitrificação, pode ter como consequência a geração e emissão de óxido nitroso (N2O). O presente trabalho avaliou a produção de óxido nitroso durante o processo de remoção de nitrogênio por lodo granular aeróbio (LGA) em um RBSG piloto, e o desempenho deste reator no tratamento de esgoto doméstico. A emissão de N2O do LGA, foi ainda, avaliada sob diferentes relações de carga orgânica e nitrogenada (DQO/NH4 de 1,55, 1,17 e 0) em um RBSG em escala de bancada. Durante todo o período monitorado, as eficiências de remoção de DBO5 no efluente tratado atingiram os critérios de qualidade de efluentes da lei estadual de Santa Catarina (= 60 mg / L ou 80% de eficiência para DBO5). A eficiência de remoção do nitrogênio amoniacal foi de 84%. A produção de N2O no reator piloto foi de 2,06 mg/L, com emissão de N2O de 2,26% do nitrogênio amoniacal oxidado durante o ciclo do reator. Observou-se nos experimentos realizados em escala de bancada uma produção total de N2O superior a 1,77 mg/L; 9,43% do nitrogênio amoniacal removido foi convertido em N2O para menor relação DQO/NH4. Constatou-se uma diminuição da taxa de remoção de nitrogênio amoniacal com a redução da razão DQO/NH4. A quantidade de N2O emitida no tempo foi de 1,41 mg N2O/ciclo na razão DQO/NH4 igual a 0, e diminuiu para 1,03 mg N2O/ciclo com o aumento da razão DQO/NH4 para 1,55. Os resultados apontaram que não foi observada nitrificação-desnitrificação simultânea significativa. Verificou-se a ocorrência de nitrificação parcial com acúmulo de nitrito e produção de N2O associada. A análise de hibridização in situ por fluorescência indicou alta abundância de bactérias oxidadoras de amônia (AOB), enquanto as bactérias oxidadoras de nitrito (NOB) foram encontradas em baixa abundância, corroborando os resultados de nitrificação parcial. A comunidade bacteriana que teve maior destaque foi representada pelas Pseudoxanthomonas sp., microrganismos desnitrificantes, encontrados em abundância relativa de 45%.Abstract : Aerobic granular sequencing batch reactors (AGSBR) have been used as a promised alternative to treat domestic and industrial wastewater because their high organic matter and nutrients removal efficiencies. However, nitrification and denitrification process used to remove nitrogen may produce and release nitrous oxide (N2O). This study evaluated the N2O production and release to atmosphere along the nitrogen removal by using a pilot-scale AGSBR. Besides, the reactor was evaluated regarding the wastewater treatment performance. Further, N2O were also evaluated in bench-scale AGSBR considering different carbon and nitrogen organic loads (COD/NH4+ as 1.55, 1.17 and zero). The effluent concentrations for BOD were always below the Environmental Santa Catarina State Directive - 14.675/2009 (= 60 mg/L or minimal BOD5 efficiency of 80%). The removal efficiency for ammonia nitrogen reached 84%. N2O production in the pilot-scale reactor ranged 2.06 mg/L while the N2O emission accounted 2.26% of the influent ammonia nitrogen oxided in the reactor. The highest N2O production (1.77 mg/L) was observed using the COD/NH4+ ratio at 1.77 while 9.3% of the ammonia nitrogen removed in the lower COD/NH4+ ratio (zero) was converted into nitrous oxide. Ammonia nitrogen removal efficiencies reduced accordingly with the reduction of COD/NH4+ ratios. The emission ranged 1.41 mg N2O/cycle at zero COD/NH4+ ratio. Then, it reduced to 1.03 mg N2O/cycle at 1.55 COD/NH4+ ratio. The results pointed that the simultaneous nitrification and denitrification process was negligible. Moreover, partial nitrification with nitrite accumulation associated to N2O production was depicted. In fact, the molecular technique in situ fluorescence hybridization highlighted higher abundance of ammonia-oxidizing bacteria (AOB) than nitrite-oxidizing bacteria (NOB), which supports the partial nitrification outcomes. The denitrify bacteria Pseudoxanthomonas sp. presented relative abundance of 45% and arose the greatest bacteria group found in granular sludge samples

Engineered AAVs for non-invasive gene delivery to rodent and non-human primate nervous systems

Gene therapy offers great promise in addressing neuropathologies associated with the central and peripheral nervous systems (CNS and PNS). However, genetic access remains difficult, reflecting the critical need for the development of effective and non-invasive gene delivery vectors across species. To that end, we evolved adeno-associated virus serotype 9 (AAV9) capsid in mice and validated two capsids, AAV-MaCPNS1 and AAV-MaCPNS2, across rodent species (mice and rats) and non-human primate (NHP) species (marmosets and rhesus macaques). Intravenous administration of either AAV efficiently transduced the PNS in rodents and both the PNS and CNS in NHPs. Furthermore, we used AAV-MaCPNS1 in mice to systemically deliver the following: (1) the neuronal sensor jGCaMP8s to record calcium signal dynamics in nodose ganglia and (2) the neuronal actuator DREADD to dorsal root ganglia to mediate pain. This conclusively demonstrates the translatability of these two systemic AAVs across four species and their functional utility through proof-of-concept studies in mice