Potential Psychotropic Drug Interactions among Drug-dependent People

Using psychiatric drugs to treat drug dependence and its comorbidities is very common. The objective of this study was to analyze the interactions between prescribed drugs for patients treated at a specialized mental health-care center for persons who use drugs, located in the state of Santa Catarina, Brazil. A cross-sectional study was conducted on secondary data collected from 2010 to 2018. We reviewed the medical records of patients aged 18 years or older who took psychotropic drugs and had any type of substance dependence. The analysis of psychotropic drug interactions was conducted in three databases: Medscape, Drug Interactions Checker, and Micromedex. We included 1,022 of the 2,322 patients attending the care center during the study period. Psychotropic drug interactions were found in 779 (76.4%) study participants, and they presented 2,292 (100%) interactions, out of which 136 (6.0%) had minor clinical risk, 537 (23.4%) had moderate risk, and 1,619 (70.6%) had major risk for the patient, totaling 172 incompatible combinations between two psychotropic drugs. Of the total number of interactions, 128 were pharmacokinetic and 44 were pharmacodynamic. The high number of psychotropic drug interactions is a serious public health issue. Psychopharmacological treatment should be carefully addressed to be safe for the patient.

Calibration of parameters in Dynamic Energy Budget models using Direct-Search methods

Dynamic Energy Budget (DEB) theory aims to capture the quantitative aspects of metabolism at the individual level, for all species. The parametrization of a DEB model is based on information obtained through the observation of natural populations and experimental research. Currently the DEB toolbox estimates these parameters using the Nelder-Mead Simplex method, a derivative-free direct-search method. However, this procedure presents some limitations regarding convergence and how to address constraints. Framed in the calibration of parameters in DEB theory, this work presents a numerical comparison between the Nelder-Mead Simplex method and the SID-PSM algorithm, a Directional Direct-Search method for which convergence can be established both for unconstrained and constrained problems. A hybrid version of the two methods, named as Simplex Directional Direct-Search, provides a robust and efficient algorithm, able to solve the constrained optimization problems resulting from the parametrization of the biological models.

Improved renal function after kidney transplantation is associated with heme oxygenase-1 polymorphism

Heme oxygenase-1 (HO-1) has a microsatellite polymorphism based on the number of guanosine-thymidine nucleotide repeats (GT) repeats that regulates expression levels and could have an impact on organ survival post-injury. We correlated HO-1 polymorphism with renal graft function. The HO-1 gene was sequenced (N = 181), and the allelic repeats were divided into subclasses: short repeats (S) (<27 repeats) and long repeats (L) (>/=27 repeats). A total of 47.5% of the donors carried the S allele. The allograft function was statistically improved six months, two and three yr after transplantation in patients receiving kidneys from donors with an S allele. For the recipients carrying the S allele (50.3%), the allograft function was also better throughout the follow-up, but reached statistical significance only three yr after transplantation (p = 0.04). Considering only those patients who had chronic allograft nephropathy (CAN; 74 of 181), allograft function was also better in donors and in recipients carrying the S allele, two and three yr after transplantation (p = 0.03). Recipients of kidney transplantation from donors carrying the S allele presented better function even in the presence of CAN.