A medical algorithm for Cotard delusion based on more than 300 literature cases.

OBJECTIVE: Cotard delusion (CD) is a rare psychiatric disorder in which the patient believes to be dead, i.e., the patient holds nihilistic delusions concerning his/her own existence. Taking into account its rarity, and possible subdiagnosis due to unawareness, most of the literature consists of case studies, complicating a more systematic approach and leading to difficulties in deciding the best clinical guidance to offer the patient suffering from CD. The objective of this work is to review the literature and propose an algorithm to help the differential diagnosis and the management of this condition. METHOD: To do so, an extensive literature research was performed using several bibliographic databases. Since data on this topic is scarce, references in every article were cross-checked, aiming to obtain all available peer-reviewed works on CD. RESULTS: Research resulted in 328 cases. Several treatment modalities were reported to improve the symptoms of CD, from pharmacotherapy - mainly consisting of antipsychotics and antidepressants - to electroconvulsive therapy. CONCLUSIONS: Despite its challenging diagnosis, the delusion can be treated with readily available care. Hopefully, this work can be a useful tool to doctors when encountering this odd affliction.

Derivatization-free determination of aminoglycosides by CZE-UV in pharmaceutical formulations.

Aminoglycosides are a relevant class of antibiotics widely used by medics and veterinaries. There are a variety of reasons that make their determination relevant, such as quality control, environment and food contamination assessment, drug-release studies, among others. The lack of a chromophore makes aminoglycoside spectrophotometric detection particularly challenging, often requiring derivatization. In this work, an indirect detection method, making use of imidazole as a probe, applying CZE was successfully tested. It did not require derivatization, which simplified the sample preparation. Suitable figures of merit were obtained; recoveries between 95 and 105%, adequate repeatability and precision, correlation coefficients (r) above 0.998, and limits of detection (LODs) of 3.2 and 11 mg/L for gentamicin and paromomycin, respectively. As a proof-of-concept, it was also applied in a simple controlled release experiment that was well fitted using the Hill equation.

Cyclohexane-1,3-dione as a derivatizing agent for the analysis of aldehydes by micelar electrokinetic chromatography with diode array detection.

Aldehydes are important compounds in a large number of samples, especially food and beverages. In this work, for the first time, cyclohexane-1,3-dione (CHD) was used as a derivatizing reagent aiming aldehyde (formaldehyde, acetaldehyde, propionaldehyde, and valeraldehyde) analysis by MEKC-DAD. The optimized separation of the derivates was performed using a voltage program (+20 kV, 0-15 min.; +23 kV, 15-17 min.) at a temperature of 26°C, and using as the running buffer a mixture containing 100 mmol/L of sodium dodecyl sulfate and 29 mmol/L of sodium tetraborate at pH 9.2, with maximum absorbance at 260 nm. CHD was compared with two other derivatizing agents: 3-methyl-2-benzothiazolinone hydrazone and phenylhydrazine-4-sulfonic acid. The CHD-aldehyde derivatives were also characterized by LC-MS. The calibration curves for all aldehydes had r2 above 0.999 and LODs ranged from 0.01 to 0.7 mg/L. The optimized methodology was applied in sugar cane brandy (cachaça) samples successfully. CHD showed to be an alternative derivatization reagent due to its stability, aqueous solubility, high selectivity and sensitivity, reduced impurities, and simple preparation steps.