Biheterocyclic ligands: synthesis, characterization and coordinating properties of bis(4-amino-5-mercapto-1,2,4-triazol-3-yl) alkanes with transition metal ions and their thermokinetic and biological studies

The Co(II), Ni(II) and Cu(II) metal ions complexes of Bis(4-amino-5-mercapto-1,2,4-triazol-3-yl) alkanes (BATs) have been prepared and characterized by elemental analysis, conductivity measurements infrared, magnetic susceptibility, the electronic spectral data and thermal studies. Based on spectral and magnetic results, the ligands are tetradentate coordinating through the N and S-atoms of BATs; six-coordinated octahedral or distorted octahedral and some times four-coordinated square planar were proposed for these complexes. Activation energies computed for the thermal decomposition steps were compared. The ligands and their metal complexes were tested in vitro for their biological effects. Their activities against two gram-positive, two gram-negative bacteria and two fungal species were found to vary from moderate to very strong.

Synthesis, characterization and thermal behaviour on solid pyruvates of some bivalent metal ions

Solid state M-L compounds, were M stands for bivalent Mn, Fe, Co, Ni, Cu, Zn and L is pyruvate, have been synthesized. Thermogravimetry and derivative thermogravimetry (TG/DTG), differential scanning calorimetry (DSC), X-Ray powder diffractometry, infrared spectroscopy, elemental analysis, and complexometry were used to characterize and to study the thermal behaviour of these compounds. The results led to information about the composition, dehydration, ligand denticity, and thermal decomposition of the isolated compounds.

Comparison of the dehydration kinetics of solid state compounds of 2-methoxybenzylidenepyruvate with some divalent metal ions

Divalent metal complexes of ligand 2-methoxybenzylidenepyruvate with Fe, Co, Ni, Cu and Zn as well as sodium salt were synthesized and investigated in the solid state. TG curves of these compounds were obtained with masses sample of 1 and 5mg under nitrogen atmosphere. Different heating rates were used to characterize and study these compounds from the kinetic point of view. The activation energy and pre-exponential factor were obtained applying the Wall-Flynn-Ozawa method to the TG curves. The obtained data were evaluated and the values of activation energy (Ea / kJ mol-1) was plotted in function of the conversion degree (α). The results show that due to mass sample, different activation energies were obtained. The results are discussed mainly taking into account the linear dependence between the activation energy and the pre exponential factor, where was verified the effect of kinetic compensation (KCE) and possible linear relations between the dehydrations steps of these compounds.

Synthesis, characterization and thermal behaviour of solid 2-methoxycinnamylidenepyruvate of some bivalent metal ions in CO2 and N2 atmospheres

Solid State M-2-MeO-CP compounds, where M stands for bivalent metals (Mn, Fe, Co, Ni, Cu and Zn) and 2-MeO-CP is 2-methoxycinnamylidenepyruvate, were synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), differential scanning calorimetry (DSC), elemental analysis and complexometry were used to establish the stoichiometry and to study the thermal behaviour of these compounds in CO2 and N2 atmospheres. The results were consistent with the general formula: M(L)2∙H2O. In both atmospheres (CO2, N2) the thermal decomposition occurs in consecutive steps which are characteristic of each compound. For CO2 atmosphere the final residues were: Mn3O4, Fe3O4, Co3O4, NiO, Cu2O and ZnO, while under N2 atmosphere the thermal decomposition is still observed at 1000 º C.

Thermal behaviour of succinic acid, sodium succinate and its compounds with some bivalent transitions metal ions in dynamic N2 and CO2 atmospheres

Thermal stability and thermal decomposition of succinic acid, sodium succinate and its compounds with Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) were investigated employing simultaneous thermogravimetry and differential thermal analysis (TG-DTA) in nitrogen and carbon dioxide atmospheres and TG-FTIR in nitrogen atmosphere. On heating, in both atmospheres the succinic acid melt and evaporate, while for the sodium succinate the thermal decomposition occurs with the formation of sodium carbonate. For the transition metal succinates the final residue up to 1180 ºC in N2 atmosphere was a mixture of metal and metal oxide in no simple stoichiometric relation, except for Zn compound, where the residue was a small quantity of carbonaceous residue. For the CO2 atmosphere the final residue up to 980 ºC was: MnO, Fe3O4, CoO, ZnO and mixtures of Ni, NiO and Cu, Cu2O.

Environmental behavior of soils and mixtures of soil-whitewash mud

The present study sought to observe the behavior of soils in natural state and in mixtures, in different ratios, with the industrial solid residue called whitewash mud. The work was conducted with samples of typical soils from the region of Alagoinhas, Bahia-Brazil. Wet chemical analysis and atomic absorption spectrophotometry were used in order to obtain the classification of the industrial solid residue. Solubilization and leaching tests were performed and X-ray diffraction and electron microscopy techniques were carried out. The results showed that the whitewash mud was classified as non-inert, but with great capacity of heavy metal retention largely owed to the kaolinite and goethite presence in the clay fraction of the soils, making it difficult to have heavy metals readily available for exchange.

Initial development and gas exchange of Talisia subalbens (Mart.) Radlk. under different shading conditions

Ecophysiological studies under semi-controlled conditions in nurseries and greenhouses are essential to enable the use of native species to recover degraded areas and for commercial planting. Talisia subalbens (Mart) Radlk, 'cascudo', is a native fruiting species of the Cerrado on the verge of extinction. The ecophysiological performance of this species was evaluated in nursery conditions under different levels of shading (full sunshine, 30%, 50% and 70%). Initial growth, biomass allocation, gas exchange and chlorophyll content of the plants were analyzed. Full sunshine cultivated plants showed a higher accumulation of total, shoot, and root dry biomass. There was no significant difference in the root/shoot ratio among the treatments. Seedlings cultivated under full sunshine and 30% shading showed higher values for height, basal diameter, and leaf area. Differences in stomata conductance and photosynthesis rate were not observed among the different shading levels. Plants cultivated under 70% of shading had higher contents of chlorophyll a, b, and total. During the initial phase with higher levels of radiation were fundamental for the development of T. subalbens seedlings.

GAS EXCHANGE IN YOUNG PLANTS OF Tabebuia aurea(Bignoniaceae Juss.) SUBJECTED TO FLOODING STRESS1

ABSTRACT The Paratudo (Tabebuia aurea) is a species occurring in the Pantanal of Miranda, Mato Grosso do Sul, Brazil, an area characterized by seasonal flooding. To evaluate the tolerance of this plant to flooding, plants aged four months were grown in flooded soil and in non-flooded soil (control group). Stomatal conductance, transpiration and CO2 assimilation were measured during the stress (48 days) and recovery (11 days) period, totalling 59 days. The values of stomatal conductance of the control group and stressed plants at the beginning of the flooded were 0.33 mol m-2s-1 and reached 0.02 mol m-2 s-1 (46th day) at the end of this event. For the transpiration parameter, the initial rate was 3.1 mol m s-1, and the final rate reached 0.2 or 0.3 mol m-2 s-1 (47/48 th day). The initial photosynthesis rate was 8.9 mmol m-2s-1 and oscillated after the sixth day, and the rate reached zero on the 48th day. When the photosynthesis rate reached zero, the potted plants were dried, and the rate was analyzed (11th day). The following values were obtained for dried plants: stomatal conductance = 0.26 mol m-2 s-1, transpiration rate = 2.5 mol m-2 s-1 and photosynthesis rate = 7.8 mmol m-2 s-1. Flooded soil reduced photosynthesis and stomatal conductance, leading to the hypertrophy of the lenticels. These parameters recovered and after this period, and plants exhibited tolerance to flooding stress by reducing their physiological activities.

Modelos de transferência de metal pesado na cana-de-açúcar adubada com composto de lixo urbano

A pesquisa aborda a reciclagem do composto de lixo urbano (CLU) como fertilizante alternativo na cana-de-açúcar e como solução social e ambiental ao acúmulo de resíduos sólidos nos centros urbanos. Utilizou-se da modelagem matemática para conhecer a dinâmica dos metais pesados, visando ao estabelecimento de critérios e procedimentos para o uso seguro do CLU, limitado pela quantidade desses elementos. Foram construídos modelos compartimentais a partir de dados de experimentos em condições controladas e parcialmente validados com dados de campo. Esse modelo descreveu a transferência de metais pesados no sistema solo-raiz-parte aérea para a cana-de-açúcar. Pôde-se concluir, pelas condições desta pesquisa, que o metal mais preocupante foi o níquel, pois demora, aproximadamente, três anos para ser atenuado no solo e chega em maior quantidade na parte aérea. Quanto aos fatores argila, óxidos e pH do solo, notou-se que, nos solos de maior poder tampão, a passagem da maioria dos metais foi mais lenta. Esse modelo pode tornar-se importante aliado na definição de leis de utilização do CLU, visando à não-contaminação ambiental, redução no acúmulo de lixo e de custos de produção.

Horizontal pressures in cylindrical metal silos and comparison with different international standards

The focus of this research was to evaluate the horizontal pressures on a cylindrical metal silo of corrugated walls and flat bottom with 1.82m diameter and 5.4m high, and to compare the values with those obtained theoretically by the ISO 11697, EP 433 and AS 3774 standards. The silo was symmetrically filled and constant speed with wheat cv. soft red for two different height/diameter ratios (H/D) and was unloaded through three orifices with a diameter of 71.6mm, one concentric and two eccentrics. Horizontal pressures were measured on the walls of the silo at three positions using hydraulic type pressure cells. The results showed that shortly after the start of the unloading, there was a mass flow above the quota of H/D = 1.2, whereas below this quota funnel flow occurred. It can be said that the EP 433 standard was more appropriate to predict horizontal pressures in silos in H/D ratio = 1.0, with eccentric unloading. For the H/D ratio = 1.5, AS 3774 standard was the one that produced values closer to the experimental.

Interposição jejunal após gastrectomia total radical por adenocarcinoma gástrico

Realizamos um estudo retrospectivo do tratamento cirúrgico do adenocarcinoma gástrico por uma gastrectomia total radical, com reconstrução do trânsito esofagoduodenal pela interposição de uma alça jejunal pediculada. Revisão de trabalhos nacionais e estrangeiros relacionados ao tratamento do adenocarcinoma gástrico pela gastrectomia total radical. De acordo com a operabilidade relacionada ao paciente e à ressecabilidade, à lesão primária e sua evolução, 126 pacientes foram submetidos à interposição de um segmento de alça jejunal após gastrectomia total radical. Ressecção oncológica total do estômago e sistematizada reconstrução técnica do reservatório gástrico e do trânsito esofagoduodenal. Nossos casos evoluíram de maneira satisfatória, não fugindo daqueles estudados na literatura. Ênfase especial foi dada ao procedimento técnico, mais anatômico e muito mais funcional, restituindo ao operado um neoestômago e um trânsito esôfago-intestinal através do duodeno. A interposição de uma alça jejunal pediculada entre o esôfago terminal e a segunda porção do duodeno age como neo-reservatório gástrico. Evita o refluxo esofágico e direciona o bolo alimentar para o delgado através do duodeno, trânsito anatômico e funcional capaz de proporcionar melhor qualidade de vida ao gastrectomizado total.

Influência da linfadenectomia radical (D2) na morbidade e mortalidade da ressecção curativa do carcinoma gástrico

A despeito da controvérsia existente na literatura com relação aos benefícios da linfadenectomia na sobrevida dos doentes submetidos a ressecções curativas para tratamento do adenocarcinoma gástrico, é inegável que a linfadenectomia ampliada (nível II na classificação japonesa) contribui para o melhor estadiamento e prognóstico destes pacientes. Este procedimento permite-nos melhor identificar aqueles pacientes que têm pior prognóstico e oferecer-lhes novas formas de terapia adjuvante. Como o principal argumento para a não realização de cirurgias mais alargadas é que estas são acompanhadas de maior morbidade e mortalidade, os autores estudaram prospectivamente parâmetros relacionados a esses índices nas gastrectomias com linfadenectomia nível 11 (D2) que tiveram intenção curativa. Para tanto, estudaram-se a taxa de mortalidade, o tempo operatório, as unidades de glóbulos transfundidas, as complicações e o tempo de internação pós-operatória. Entre dezembro de 1992 e fevereiro de 1997 foram internados 86 pacientes com diagnóstico de adenocarcinoma gástrico, dos quais, em 27, atendidos por uma mesma equipe interessada no tratamento destes tumores, houve ressecção cirúrgica com intenção curativa e o tratamento consistiu de gastrectomia acompanhada de linfadenectomia D2. A gastrectomia subtotal foi realizada em 17 doentes, a total em três e a total ampliada em sete. Nove doentes tinham tumores superficiais. Não houve mortalidade entre os pacientes submetidos a ressecções D2; o tempo médio operatório foi de 208,7 minutos; receberam em média 0,2 unidades de glóbulos e a incidência de complicações foi de 33,3%. A permanência hospitalar pós-operatória média foi de 8,6 dias. Foram estudados 854 linfonodos, dos quais 22,1% eram positivos para tumor metastático. Os autores concluem que a dissecção D2 pode ser feita de forma segura e não deve ser evitada por causa do risco de complicações. Permite estadiamento anatomopatológico mais preciso e melhor avaliação do prognóstico destes pacientes.

Esofagectomia de resgate após quimiorradioterapia radical exclusiva: resultados do departamento de cirurgia abdôminopélvica do Instituto Nacional de Câncer

OBJETIVO: Relatar a experiência e os resultados da Seção de Cirurgia Abdôminopélvica do Instituto Nacional de Câncer (INCA) com a esofagectomia de resgate em paciente portador de câncer de esôfago recidivado após tratamento quimiorradioterápico exclusivo. MÉTODO: Foram analisados retrospectivamente 14 pacientes portadores de câncer de esôfago recidivado e que foram submetidos à esofagectomia de resgate entre março de 1999 e maio de 2006. Todos os pacientes incluídos no estudo receberam tratamento primário quimiorradioterápico radical exclusivo conforme protocolo RTOG 85-01 e apresentaram persistência ou recidiva de doença. RESULTADOS: A idade média foi de 63 anos (39-72 anos). Oito pacientes eram do sexo masculino e seis pacientes do sexo feminino. Nove pacientes apresentavam o tumor localizado no esôfago médio e cinco pacientes apresentavam doença no esôfago distal, sendo carcinoma epidermóide em 12 pacientes e adenocarcinoma em dois pacientes. A mediana do tempo cirúrgico foi de 305 minutos (240-430 minutos). A ressecção completa do tumor (cirurgia R0) foi realizada em 13 pacientes e somente um paciente apresentou doença residual macroscópica em ápice pulmonar. A morbidade total da série foi de 69,2 %. A mortalidade operatória foi zero (todos os pacientes evoluíram para alta hospitalar). CONCLUSÃO: A esofagectomia de resgate demonstrou-se factível tecnicamente porém apresenta elevada morbidade operatória. Esta modalidade cirúrgica corresponde atualmente ao melhor tratamento disponível para se obter cura nos casos de tumor recidivado ou que tenho persistido com doença após quimiorradioterapia radical exclusiva. Todos os outros tipos de tratamento são considerados paliativos e com resultados de sobre-vida desapontadores.

Tratamento cirúrgico na recidiva retroperitoneal tardia por carcinoma renal de células claras após nefrectomia radical

Late renal cell carcinoma recurrence in the renal fossa is a rare event. This condition occurs in 1 to 2% of radical nephrectomies. We reported a late recurrence at the renal fossa about four and half years after radical nephrectomy due to a renal cell carcinoma (RCC) without metastasis elsewhere. Diagnosis in an outpatient follow-up was made during an abdominal computed tomography and we observed a retroperitoneal mass in the renal fossa. The excision at the recurrence area was made through a subcostal transversal incision without any difficulty. After 6 months from this second procedure, there was no evidence of recurrence. The surgical aggressive treatment for late retroperitoneal RCC recurrence is a good method in this rare situation. Abdominal computed tomography must be done during long periods of follow-up for patients with radical nephrectomy for RCC to search for late retroperitoneal recurrences.

Cistectomia radical laparoscópica com reservatório ileal

Worldwide experience with laparoscopic radical cystectomy is increasing in the last few years. We describe a 29-year-old female who underwent a laparoscopic radical cystectomy with ileal reservoir for a bladder sarcoma. Operative time was 405 minutes and estimated blood loss was 500 mL. She had an uneventful postoperative course and was discharged in the fifth postoperative day. Key-words: bladder, cystectomy, laparoscopy, urinary diversion, bladder neoplasms.