ABSTRACT
The objective of the study is to determine the optimal conditions for blood sample preparation by liquid-liquid extraction using mathematical planning of the experiment by the example of forensic chemical study of verapamil. Evaluation of verapamil recovery from blood samples was performed according to the scheme of multivariate three-level experimental planning using the Box-Behnken design. The effect of aqueous phase pH, the ratio of chloroform to n-butanol in the extraction agent, extraction and centrifugation time, addition of sodium chloride, and the ratio of sample and extraction agent volumes on the recovery was studied. The algorithm using mathematical planning and development of liquid-liquid extraction model of target analyte can be recommended for analysis procedure optimization in forensic chemistry.
Subject(s)
Liquid-Liquid Extraction , Verapamil , WaterABSTRACT
The objective of this work is to evaluate the possibility of biological fluids sample preparation in forensic toxicology using a molecularly imprinted sorbent based on acrylic acid derivatives. Phenylpiracetam has similar physicochemical properties to those of pyrrolidinophenone derivatives and reproduces their behavior during solid-phase extraction. The phenylpiracetam recovery from blood and urine model samples is 75% for concentration range of 100.0-6000.0 ng/ml. The accuracy of phenylpiracetam extraction does not exceed ±12% for blood samples and ±6% for urine samples. The repeatability is no more than 16% and 13% for blood and urine samples, respectively. A study of the cross-reactivity of the molecularly imprinted sorbent with some drugs showed the selectivity of the sample preparation procedure.
Subject(s)
Molecular Imprinting , Forensic Toxicology , Solid Phase ExtractionABSTRACT
The aim of the work is to test theoretical prognosis of metrological characteristics of methods of quantitative determination in forensic chemical analysis on the example of method of determination of verapamil content in blood by thin layer chromatography with computer densitometry. The algorithm of prognostic determination of relative error for methods of quantitative analysis in forensic chemical examination using computer program «ChemMetrEvaluation 1.0¼ is offered. The implementation of the algorithm is based on a detailed analysis of error estimation of measurements at the stages of sample preparation, measuring the value of the analytical signal.
Subject(s)
Forensic Medicine , Verapamil , Chromatography, Gas , Chromatography, Thin Layer , Densitometry , Verapamil/analysisABSTRACT
The purpose of the work is the development of mathematical models in the forensic diagnosis of poisonings by the main groups of toxicologically important substances, on the basis of biochemical characteristics of blood. The most informative forensic and biochemical indicators of cadaveric blood used to detect lethal poisoning are the urea content, total protein content, and the ratio of urea to creatinine. Mathematical models of poisoning can be used to diagnose poisoning with narcotic drugs, psychotropic substances and substitutes of ethyl alcohol.
Subject(s)
Ethanol/blood , Forensic Medicine/methods , Narcotics/blood , Poisoning/diagnosis , Psychotropic Drugs/blood , Cadaver , Ethanol/poisoning , Humans , Models, Theoretical , Narcotics/poisoning , Poisoning/blood , Psychotropic Drugs/poisoningABSTRACT
Roentgenofluorescent spectrometry was used for identification of chemical elements and their quantitation in the zones of damage to different knitted fabrics done by shots from traumatic gas gun with rubber bullets.
Subject(s)
Elements , Firearms , Forensic Ballistics , Rubber , Textiles/analysis , Spectrometry, X-Ray EmissionABSTRACT
Multifactorial pathogenesis of the "diabetic foot" syndrome suggests advisability to single out some clinical pathogenetic forms, depending on basic causes of the lesions: due to neuropathy, osteoarthropathy, neuro-ischemic factors. The authors has developed the algorithm which enables to diagnose various forms of the syndrome and differentiate the treatment. The most important treatment modalities include unloading and podiatric measures as well as surgery, systemic antibacterial and glucolytic therapy. Conservative or surgical antiischemic measures are indicated only in demonstration of the degree of the ischemic damage in the lower extremities by Doppler ultrasonography and measurement of local oxygenation of the skin. The combined differentiated treatment in 142 patients with diabetic lesions of the feet has resulted 97.2% favourable outcomes in neuropathy and 86.5% successful outcomes in neuroischemic damages. Local oxygenation of dorsal skin of the foot (< 20 mm Hg) indicates that amputation above the ankle is highly probable.
Subject(s)
Diabetic Foot/diagnosis , Diabetic Foot/therapy , Amputation, Surgical , Diagnosis, Differential , Humans , Oximetry , Prognosis , Ultrasonography, Doppler , Vasodilator Agents/therapeutic useABSTRACT
Examinations of 48 patients with the syndrome of "diabetic foot" (IV-V degree according to Wagner classification), have shown advantages of prolonged epidural anesthesia (EA) carried out during pre-, intra-, and postoperative (6-7 days) period. This method has relieved pain during postoperative period with minimal impact on carbohydrate metabolism and central hemodynamics. Moreover prolonged EA is a basic prophylactic method against the development of phantom painful syndrome in patients with amputated extremity. The prolonged postoperative EA is a reliable method for modification of surgical stress-response, being especially important in patient, afflicted with a severe form of diabetes mellitus who represent a high surgical and anesthesiological risk group.
