Effect of temperature on chiral separation of ketamine enantiomers by high-performance liquid chromatography

A semipreparative column packed with microcrystalline cellulose triacetate (MCTA) was used to separate ketamine enantiomers by high-performance liquid chromatography (HPLC). The effect of temperature on the kinetics of mass transfer and equilibrium constants were evaluated by the moment analysis at 303, 313, and 323 K. Total porosity, bed porosity, and equilibrium constants were measured by the first moment. Pore diffusion and axial dispersion coefficients were evaluated by the second moment. It was observed that band broadening decreased with increasing temperature. The equilibrium constants were found to be greater than unity and decreasing with increasing temperature. The pore diffusion coefficients increased with increasing temperature and the main contribution to the band broadening was attributed to low mass transfer kinetics. The pore diffusion coefficients controlled the mass-transfer process in MCTA column. These results may be used to the determination of operating conditions and computational simulation of a chromatographic separation in simulated moving bed unity.40132593261

Clinical and Patient-Centered Outcomes After Minimally Invasive Non-Surgical or Surgical Approaches for the Treatment of Intrabony Defects: A Randomized Clinical Trial

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Background: The present study aims to compare the performance of minimally invasive non-surgical and surgical approaches for the therapy of intrabony defects. Methods: Twenty-nine patients who presented with intrabony defects were randomly assigned to: 1) a minimally invasive non-surgical technique (MINST) group, or 2) minimally invasive surgical technique (MIST) group. The chair time of each therapeutic procedure was calculated. The probing depth (PD), position of the gingival margin (PGM) and relative clinical attachment level (RCAL) were evaluated at 3 and 6 months after treatments. The patient perception of discomfort/pain experienced during and after therapy and patient satisfaction regarding treatments were also evaluated. Results: Significant PD reductions, RCAL gains, and no changes in the PGM were obtained at 3 and 6 months in MINST and MIST groups (P<0.05). No differences were observed between groups at any time points (P>0.05). Patient-oriented outcomes did not demonstrate differences between therapeutic approaches (P>0.05). Significant higher chair times were required in the MIST group than in the MINST group (P<0.05). Conclusions: Minimally invasive non-surgical and surgical approaches were successfully used for the treatment of intrabony defects and achieved periodontal health in association with negligible morbidity and suitable patient satisfaction. However, non-surgical therapeutic modality presented an advantage in terms of a reduction of treatment chair time. J Periodontol 2011;82:1256-1266.82912561266Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)National Counsel of Technological and Scientific Development, Brasilia - DF, Brazil [303693/2009-6]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [08/50027-4]National Counsel of Technological and Scientific Development, Brasilia - DF, Brazil [303693/2009-6

A dor crônica sob o olhar médico: modelo biomédico e prática clínica The medical perspective towards chronic pain: biomedical model and clinical practice

Este trabalho teve como objetivo compreender os sentidos da dor crônica no discurso e na prática clínica de médicos nos espaços terapêuticos de duas Clínicas de Dor, situadas em hospitais-universitários de Salvador (Bahia) e São Paulo, Brasil. Foi realizado um estudo etnográfico a partir de observação participante e entrevistas semi-estruturadas com médicos (terapeutas e coordenadores de serviço). A análise dos dados foi inspirada nos modelos clínicos desenvolvido por Byron Good e o projeto de racionalidades médicas, formulado por Madel Luz. O reconhecimento da dor crônica pela biomedicina enquanto doença e não como sintoma, sua invisibilidade ao olhar médico, sua incomunicabilidade e inevitabilidade foram os sentidos emergentes neste trabalho. A valorização do encontro humano na clínica, o exercício da compreensão em contraposição à suspeição (distanciamento) e a construção de projetos terapêuticos negociados e sustentáveis a longo tempo foram apontados pelos informantes como necessários no trabalho com dor crônica.<br>This study aimed to shed light on the meanings ascribed to chronic pain in medical discourse and clinical practice in two Pain Clinics located in University hospitals in Salvador (Bahia) and São Paulo, Brazil. An ethnographic approach used participant observation and semi-structuralized interviews with attending and managing physicians. Data analysis drew on the clinical models developed by Byron Good and the medical rationalities project formulated by Madel Luz. The meanings emerging from the study were the recognition of chronic pain by biomedicine as a disease rather than a symptom, its invisibility to physicians, and its non-communicability and inevitability. The informants suggested the need for valorization of the human encounter in the clinic, exercise of understanding as opposed to suspicion, and negotiation of sustainable therapeutic projects