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Biomedical subjects

B Ludes

Publications and source records attributed to B Ludes.

At least 19 recordsLinked to original sources

STR typing of ancient DNA extracted from hair shafts of Siberian mummies.

The aim of this study was to determine if ancient hair shafts could be suitable for nuclear DNA analysis and to develop an efficient and straightforward protocol for DNA extraction and STR typing of ancient specimens. The developed method was validated on modern and forensic samples and then successfully applied on ancient hairs collected from Siberian mummies dating from the 16th to the early 19th centuries. In parallel extractions including or excluding a washing step were performed at least two times for each sample in order to evaluate the influence on the quantity of nuclear DNA yielded and on the typing efficiency. Twelve ancient individuals were analyzed through our approach and full and reliable profiles were obtained for four of them. These profiles were validated by comparison with those obtained from bone and teeth DNA extracted from the same ancient specimens. The present study demonstrates that the washing step cannot be considered as deleterious for DNA retrieval since the same results were obtained by the two approaches. This finding challenges the hypothesis that recoverable nuclear DNA is only found on the outer surface of hair shafts and provides evidence that nuclear DNA can be successfully extracted from ancient hair shafts. The method described here constitutes a promising way for non-invasive investigations in ancient DNA analysis for precious or historical samples as well as forensic casework analyses.

Bone and Bones↗

Mitochondrial DNA analysis of horses recovered from a frozen tomb (Berel site, Kazakhstan, 3rd Century BC).

Sequence polymorphism of the mitochondrial DNA D-loop was used to determine the genetic diversity of horses recovered from a Scythian princely tomb dating from the beginning of the 3rd century BC. Eight haplotypes were found among the 13 ancient horse samples tested. Phylogenetical analysis showed that these ancient horse's sequences, along with two Yakut ones, were distributed throughout the tree defined by modern horses' sequences and are closely related to them. No clear geographical affiliation of the specimens studied was thus determined. Our work, among others, supports the very ancient origin of the matrilines in horses.

Animals↗

Testing for zopiclone in hair application to drug-facilitated crimes.

The use of a drug to modify a person's behaviour for criminal gain is not a recent phenomenon. However, the recent increase in reports of drug-facilitated crimes (sexual assault, robbery) has caused alarm in the general public. The drugs involved can be difficult to detect due to low dosages or chemical instability. They possess amnesic properties and can be quickly cleared from the body fluids. In these situations, blood or even urine can be of poor interest. This is the reason why this laboratory developed an original approach based on hair testing by LC-MS/MS. Zopiclone (Imovane), due to its short half-life associated with rapid hypnotic activity, is considered as a compound of choice to sedate victims. To document the detection of zopiclone in hair, we first tested specimens obtained from two volunteers who had ingested a single 7.5 mg Imovane tablet, and from repetitive consumers of zopiclone. After pH 8.4 buffer incubation and extraction with methylene chloride/diethyl ether (80/20 (v/v)), hair extracts were separated on a Xterra MS C18 column using a gradient of acetonitrile and formate buffer. Zopiclone and diazepam-d5, used as internal standard, were detected by tandem mass spectrometry. A single exposure to zopiclone was detectable in the first hair segment of two volunteers at concentration of 5.4 and 9.0 pg/mg, respectively. Hair from repetitive consumers tested positive for zopiclone at concentrations of 37 and 66 pg/mg. Hair analysis was applied to two authentic criminal cases. In the first one, zopiclone tested positive in the corresponding hair segment at 4.2 pg/mg, in accordance with a single exposure to the drug. In the other expertise, zopiclone was detected in the two segments analyzed, at 21.3 and 21.5 pg/mg, making unlikely the hypothetical single exposure to zopiclone.

Adolescent↗

Evaluation of the One-Step ELISA kit for the detection of buprenorphine in urine, blood, and hair specimens.

A solid-phase enzyme immunoassay involving microtiter plates was recently proposed by International Diagnostic Systems corporation (IDS) to screen for buprenorphine in human serum. The performance of the kit led us to investigate its applicability in other biological matrices such as urine or blood, and also hair specimens. Low concentrations of buprenorphine were detected with the ELISA test and confirmed by HPLC/MS (buprenorphine concentrations measured by HPLC/MS: 0.3 ng/mL in urine, 0.2 ng/mL in blood, and 40 pg/mg in hair). The intra-assay precision values were 8.7% at 1 ng/mL of urine (n = 8), 11.5% at 2 ng/mL in serum (n = 8), and 11.5% at 250 pg/mg of hair (n = 8), respectively. The immunoassay had no cross-reactivity with dihydrocodeine, ethylmorphine, 6-monoacetylmorphine, pholcodine, propoxyphene, dextromoramide, dextrometorphan at 1 and 10 mg/L, or codeine, morphine, methadone, and its metabolite EDDP. A 1% cross-reactivity was measured for a norbuprenorphine concentration of 50 ng/mL. Finally, the immunoassay was validated by comparing authentic specimens results with those of a validated HPLC/MS method. From the 136 urine samples tested, 93 were positive (68.4%) after the ELISA screening test (cutoff: 0.5 ng/mL) and confirmed by HPLC/MS (buprenorphine concentrations: 0.3-2036 ng/mL). From the 108 blood or serum samples screened, 27 were positive (25%) after the ELISA test with a cutoff value of 0.5 ng/mL (buprenorphine concentrations: 0.2-13.3 ng/mL). Eighteen hair specimens were positive (72%) after the screening (cutoff: 10 pg/mg) and confirmed by LC/MS (buprenorphine concentrations: 40-360 pg/mg). The ELISA method produced false positive results in less than 21% of the cases, but no false negative results were observed with the immunological test. Four potential adulterants (hypochloride 50 mL/L, sodium nitrite 50 g/L, liquid soap 50 mL/L, and sodium chloride 50 g/L) that were added to 10 positive urine specimens (buprenorphine concentrations in the range 5.3-15.6 ng/mL), did not cause a false negative response by the immunoassay.

Buprenorphine↗

Windows of detection of zolpidem in urine and hair: application to two drug facilitated sexual assaults.

A LC-MS/MS method for the detection of zolpidem in hair was developed to detect this drug after a single dose in possible drug facilitated sexual assaults. To determine the window of detection of zolpidem in both urine and hair, three volunteers received a 10 mg dose. Urine specimens were collected each 12 h for 144 h. Hair was sampled 3-5 weeks after exposure. Hair and urine extracts were separated on a Xterra MS C18 column using a gradient of acetonitrile and formate buffer. For each compound, detection was related to two daughter ions. Zolpidem was detected for up to 60 h in urine with peak concentrations obtained at 12 h. A single exposure to zolpidem was detected in hair at concentrations ranging from 1.8 to 9.8 pg/mg. Hair analysis was applied to two possible criminal cases. In the first case, zolpidem tested positive in the corresponding hair segment at 4.4 pg/mg. In the other case, zolpidem was detected in all the segments analyzed, demonstrating likely previous drug use in addition to recent exposure associated with a positive blood result.

Adult↗

Entomotoxicology for the forensic toxicologist: much ado about nothing?

We present a series of 29 necropsies in which organic compounds (including benzodiazepines, barbiturates, antidepressants, phenothiazine, opiates, cannabinoids, meprobamate, digoxin and nefopam) were detected in arthropod larvae sampled on human corpses. No correlation was observed between drug concentrations in the larvae versus human samples. When tested, inter-larvae and inter-site variations of drug concentrations (i.e., within larvae when analyzed separately, and within anatomic sites when larvae were grouped according to their site of sampling) were enormous and not reproducible from one case to another, confirming that arthropod larvae are unreliable for quantitative toxicological analysis. Since drugs identified in maggots are always detectable in the cadaver too, we conclude that larvae analysis is of almost no interest for practical forensic casework.

Animals↗

Results of a collaborative study of the EDNAP group regarding mitochondrial DNA heteroplasmy and segregation in hair shafts.

A collaborative exercise was carried out by the European DNA Profiling Group (EDNAP) in order to evaluate the distribution of mitochondrial DNA (mtDNA) heteroplasmy amongst the hairs of an individual who displays point heteroplasmy in blood and buccal cells. A second aim of the exercise was to study reproducibility of mtDNA sequencing of hairs between laboratories using differing chemistries, further to the first mtDNA reproducibility study carried out by the EDNAP group. Laboratories were asked to type 2 sections from each of 10 hairs, such that each hair was typed by at least two laboratories. Ten laboratories participated in the study, and a total of 55 hairs were typed. The results showed that the C/T point heteroplasmy observed in blood and buccal cells at position 16234 segregated differentially between hairs, such that some hairs showed only C, others only T and the remainder, C/T heteroplasmy at varying ratios. Additionally, differential segregation of heteroplasmic variants was confirmed in independent extracts at positions 16093 and the poly(C) tract at 302-309, whilst a complete A-G transition was confirmed at position 16129 in one hair. Heteroplasmy was observed at position 16195 on both strands of a single extract from one hair segment, but was not observed in the extracts from any other segment of the same hair. Similarly, heteroplasmy at position 16304 was observed on both strands of a single extract from one hair. Additional variants at positions 73, 249 and the HVII poly(C) region were reported by one laboratory; as these were not confirmed in independent extracts, the possibility of contamination cannot be excluded. Additionally, the electrophoresis and detection equipment used by this laboratory was different to those of the other laboratories, and the discrepancies at position 249 and the HVII poly(C) region appear to be due to reading errors that may be associated with this technology. The results, and their implications for forensic mtDNA typing, are discussed in the light of the biology of hair formation.

DNA, Mitochondrial↗

Genetic analysis of a Scytho-Siberian skeleton and its implications for ancient Central Asian migrations.

The excavation of a frozen grave on the Kizil site (dated to be 2500 years old) in the Altai Republic (Central Asia) revealed a skeleton belonging to the Scytho-Siberian population. DNA was extracted from a bone sample and analyzed by autosomal STRs (short tandem repeats) and by sequencing the hypervariable region I (HV1) of the mitochondrial DNA. The resulting STR profile, mitochondrial haplotype, and haplogroup were compared with data from modern Eurasian and northern native American populations and were found only in European populations historically influenced by ancient nomadic tribes of Central Asia.

Asia↗

Testing for kavain in human hair using gas chromatography-tandem mass spectrometry.

A sensitive, specific and reproducible method for the quantitative determination of kavain in human hair has been developed. The sample preparation involved a decontamination step of the hair with methylene chloride. The hair sample (about 50 mg) was incubated in 1 ml of methanol for 1 h, in an ultrasonic bath, in presence of 20 ng of methaqualone-d7 used as internal standard. The methanolic solution was evaporated to dryness, and the residue reconstituted by adding 30 microl of methanol. A 2 microl aliquot of the extract was injected onto the column (Optima5-MS capillary column, 5% phenyl-95% methylsiloxane, 30 m x 0.25 mm i.d. x 0.25 mm film thickness) of a Hewlett-Packard (Palo Alto, CA) gas chromatograph (5890). Kavain was detected by its parent ion at m/z 230 and daughter ions at m/z 111 and 202 through a Finnigan TSQ 700 MS/MS system. The assay was capable of detecting 30 pg/mg of kavain (limit of detection (LOD)). Linearity was observed for kavain concentrations ranging from 100 to 2000 pg/mg with a correlation coefficient of 0.998. Intra-day precision at 400 pg/mg was 13.7%. The analysis of a segment of hair, obtained from an occasional consumer, revealed the presence of kavain at the concentration of 418 pg/mg. A higher concentration (1708 pg/mg) was detected in the corresponding pubic hair.

Calibration↗

Determination of heroin after embalmment.

A 30-year-old male died in Thailand after a scuffle. The corpse was embalmed and repatriated to France where an autopsy was performed. As usual in cases of embalmment, fluids such as blood and urine were unavailable and the toxicological analyses was performed on the bile and the liver. An overdose of heroin was determined as the cause of death. A review of the literature indicates that several drugs can be detected in fluids and tissues that contain formaldehyde. This case demonstrates that in embalmed corpses, toxicological assessment is still possible, e.g. after heroin fatalities.

Adult↗

Screening procedure for eight quaternary nitrogen muscle relaxants in blood by high-performance liquid chromatography-electrospray ionization mass spectrometry.

A screening procedure was developed for the identification and the quantification of eight quaternary nitrogen muscle relaxants, including d-tubocurarine, alcuronium, pancuronium, vecuronium, atracurium, mivacurium, rocuronium and mebezonium, in blood samples. The procedure involves ion-pair extraction with methylene chloride at pH 5.4, reversed-phase HPLC separation and electrospray ionization mass spectrometry detection. The procedure was validated in terms of linearity (0.929 5 for all the target compounds at 0.1 mg/l). The screening test was found satisfactory and applied in two fatal deaths. In the first case, toxicological investigations on biological fluids collected during the autopsy revealed the presence of vecuronium (1.2 and 0.6 mg/l in blood and urine, respectively) and its desacetylated metabolite, 3-hydroxy-vecuronium (4.4 and 0.7 mg vecuronium equivalent/l in blood and urine, respectively). In the second forensic case, blood analysis showed high levels of mebezonium (6.5 mg/l). The developed procedure was found suitable for forensic investigations.

Adult↗

Comparison of the prevalence of alcohol, cannabis and other drugs between 900 injured drivers and 900 control subjects: results of a French collaborative study.

A collaborative case-control study was conducted in France in order to determine the prevalence of alcohol, cannabinoids, opiates, cocaine metabolites, amphetamines and therapeutic psychoactive drugs in blood samples from drivers injured in road accidents and to compare these values with those of a control population. Recruitment was performed in emergency departments of six university or general hospitals and comprised 900 drivers involved in a non-fatal accident and 900 patients (controls) who attended the same emergency units for a non-traumatic reason. Drivers and controls were matched by sex and age. Alcohol was determined by flame ionization-gas chromatography, drugs of abuse (DOA) by gas chromatography-mass spectrometry with the same analytical procedures in the six laboratories, and medicines by high performance liquid chromatography with diode array detection. Blood alcohol concentration exceeding 0.5 g/l (i.e. the legal French threshold) was found in 26% of drivers and 9% of controls. In the 18-27 years age range, alcohol was the only toxic found in blood samples of 17% drivers and 5% controls, leading to an odds-ratio (OR) of 3.8. A significant relationship was found between alcohol blood concentrations and OR values. All age groups confounded, the main active substance of cannabis, Delta(9) tetrahydrocannabinol (THC), was found in 10% of drivers and 5% of controls. In the less than 27 years old, THC (>1 ng/ml) was detected alone in the blood of 15.3% drivers and of 6.7% controls, giving OR=2.5, whereas there was no link between THC blood concentrations and OR value. THC was found alone in 60% of cases and associated with alcohol in 32%, with OR=4.6 between drivers and controls for this association. The difference in morphine prevalence between drivers (2.7%) and controls (0.03%) was highly significant (P<0.001), with OR=8.2. The number of positive cases for amphetamines and cocaine metabolites was too low for reaching any interpretation. The most frequently observed psychoactive therapeutic drugs were by far benzodiazepines, that were found alone in 9.4% of drivers and 5.8% of controls, which led to OR=1.7 (P<0.01). This study demonstrates a higher prevalence of opiates, alcohol, cannabinoids and the combination of these last two compounds in blood samples from drivers involved in road accidents than in those from controls, which suggests a causal role for these compounds in road crashes.

Accidents, Traffic↗

Enzyme immunoassay validation for the detection of buprenorphine in urine.

A solid-phase enzyme immunoassay involving microtiter plates was proposed by Microgenics to screen buprenorphine in urine. The intra-assay precision at 10 ng/mL was 7.7% (coefficient of variation). The immunoassay was determined to have no cross-reactivity with codeine, dihydrocodeine, morphine, ethylmorphine, 6-monoacetylmorphine, methadone, pholcodine, propoxyphene, dextromoramide, and dextromethorphan at 1 and 10 mg/L. A low cross-reactivity (3% at 1 ng/mL) was observed at low concentrations of norbuprenorphine. After comparing this new immunological test (Singlestep ELISA) for 76 urine specimens with our validated high-performance liquid chromatography-electrospray mass spectrometry (HPLC-ES-MS) procedure, an optimum cutoff concentration of 2 ng/mL was determined for the kit. At this cutoff, the screening assay was able to determine more than 90% of true results with 43.4% true positives and 48.7% true negatives. Four positive urines (5.3%) were not confirmed by HPLC-ES-MS. In only one case, the negative urine test was confirmed as positive by HPLC-ES-MS (buprenorphine: 62.5 ng/mL). Buprenorphine concentrations determined by HPLC-ES-MS ranged from 1.2 to 1052 ng/mL. Of the four potential adulterants (hypochloride 50 mL/L, sodium nitrite 50 g/L, liquid soap 50 mL/L, and sodium chloride 50 g/L) that might be added to a positive urine specimen, none were able to cause a false-negative response by the immunoassay. The results of this study support the concept that the Singlestep ELISA for buprenorphine determination in urine should be considered as a new, valided screening procedure.

Buprenorphine↗

HPLC-MS for the determination of sildenafil citrate (Viagra) in biological fluids. Application to the salivary excretion of sildenafil after oral intake.

An original high-performance liquid chromatography-mass spectrometry (HPLC-MS) procedure was developed for the determination of sildenafil in biological fluids. Liquid-liquid extraction was performed by chloroform/2-propanol/n-heptane (25:10:65, v/v) at pH 9.5 with 300 ng of buprenorphine-d4 as the internal standard (IS). After agitation (10 min) and centrifugation (3500 x g, 10 min), the organic phase was evaporated and the dry extract resuspended in 25 microL methanol, from which 2 microL was injected onto a NovaPak C18 (Waters) HPLC column. Separation was carried out by a gradient of (acetonitrile + 10 microg/mL trimethylamine) in 2mM NH4COOH pH 3.0 buffer (35-70% in 9 min). Detection was done by a PerkinElmer Sciex API-100 single-quadrupole mass analyzer with an ionspray interface operated in positive-ion mode. MS data were collected as either TIC or SIM at m/z (475 + 534) or (475 + 283) for sildenafil, depending on the potential applied at the ion sampling orifice (0 V or + 100 V). The retention times of sildenafil and the IS were 4.20 and 5.07 min, respectively. Extraction recoveries were always > 87%. LOD and LOQ were 0.2 and 0.5 ng/mL whatever the biological fluid tested. The method appears specific, extremely sensitive, and relatively simple in both equipment and sample preparation. As an example, we present the results of a preliminary study on the salivary excretion of sildenafil following the oral intake (T0) of 25 mg Viagra in a 38-year-old volunteer. Sildenafil was detectable in oral fluid at T0 + 0.5 h (1.2 ng/mL) and peaked at T0 + 1.5 h (8.3 ng/mL), whereas at the same time its plasma concentration was 72.4 ng/mL. Salivary concentrations then rapidly decreased, and the last detectable value (0.9 ng/mL) was at T0 + 5.5 h. It is suggested that the salivary excretion pattern of sildenafil resembles that of benzodiazepines (high plasma protein binding, low saliva-to-plasma ratio).

Administration, Oral↗

HPLC/MS findings in a fatality involving sustained-release verapamil.

A fatality involving verapamil, a calcium channel blocker agent, is presented. A 51-year old male ingested 7200 mg of sustained-release (SR) verapamil at T0 and died 40 hours later of refractory, mixed shock and multiorgan failure. The symptoms displayed during hospitalization were quite typical and involved altered consciousness, hypotension, bradycardia, atrioventricular block, metabolic acidosis and renal failure. Verapamil and its primary metabolite, norverapamil, were assayed on eight plasma and two urine samples, successively taken between the admission to the ICU (T0 + 4 hours) and time of death, using an original high-performance liquid chromatography/mass spectrometry (HPLC/MS) procedure with verapamil-d3 as internal standard. Plasma verapamil and norverapamil levels on admission were 0.94 and 1.36 microg/mL, respectively, then verapamil remained practically unchanged throughout the hospitalization (0.85 microg/mL at T0 + 40 hours). The discussion focuses on the detrimental role of SR formulations in overdose, with special emphasis on the risk of pharma-cobezoar development already reported with SR-verapamil. To our knowledge, this is the first report of a verapamil fatality documented by repeated plasma measurements of the drug during the antemortem period.

Calcium Channel Blockers↗

Genetic analysis of human remains from a double inhumation in a frozen kurgan in Kazakhstan (Berel site, Early 3rd Century BC).

The discovery of a big barrow of the Saka period in eastern Kazakhstan between the Russian and the Chinese borders provided the opportunity to excavate a frozen burial site. In the burial chamber, there was a wooden sarcophagus with two human bodies. The skeletons of these two individuals, a man and a woman, were well preserved. A genetic study based on STRs and mitochondrial DNA analyses was undertaken in order to determine whether these human remains belonged to close relatives. Results were obtained for all the markers. Nevertheless, nuclear STRs did not allow a clear conclusion concerning the relationship, but analysis of mitochondrial DNA showed that these skeletons were not close relatives.

Adult↗

Last performance with VIAGRA: post-mortem identification of sildenafil and its metabolites in biological specimens including hair sample.

A 43-year-old man was found dead in a hotel room during a sexual relation with a colleague.He was treated both for cardiovascular disease and for erectile dysfunction with VIAGRA. A pillbox was found in the room with several tablets of verapamil (Isoptine), trimetazidine (Vastarel), yohimbine and bromazepam (Lexomil). A box of VIAGRA 25mg was found in his raincoat and two tablets were missing. His wife declared during the investigation that he was also treated by trinitrine. Autopsy revealed severe coronary artery sclerosis as well as signs of previous myocardial infarctions. Blood, urine, bile, gastric content and hair and representative tissues for histology were collected for toxicological analysis. Sildenafil and yohimbine were screened with liquid chromatography/mass spectrometry (LC/MS) and trinitrine with headspace injection (HS)/GC/MS. Verapamil and trimetazidine were identified and quantified with LC/diode array detection (DAD). Sildenafil was identified in blood, urine, bile and gastric content at 105, 246, 1206 and 754ng/ml, respectively. Hair concentration was 177pg/mg. The desmethyl metabolite was quantified in urine at 143ng/ml. Blood concentrations of verapamil and trimetazidine were measured at 659 and 2133ng/ml, respectively and were above therapeutic ranges. Trinitrine and yohimbine were not identified. These results confirm the absorption of sildenafil, verapamil and trimetazidine before the death and hair analysis indicates the chronic use of sildenafil. To the author's knowledge, this is the first report of a fatal sildenafil-verapamil association, probably by hypotension and cardiac dysrhythmia.

Adult↗

Doping control for methenolone using hair analysis by gas chromatography-tandem mass spectrometry.

A sensitive, specific and reproducible method for the quantitative determination of methenolone in human hair has been developed. The sample preparation involved a decontamination step of the hair with methylene chloride. The hair sample (about 100 mg) was solubilized in 1 ml 1 M NaOH, 15 min at 95 degrees C, in presence of 1 ng testosterone-d3 used as internal standard. The homogenate was neutralized and extracted using consecutively a solid-phase (Isolute C18 eluted with methanol) and a liquid-liquid (pentane) extraction. The residue was derivatized by adding 50 microl MSTFA-NH4I-2-mercaptoethanol (1000:2:5, v/v/v), then incubated for 20 ml at 60 degrees C. A 1.5-microl aliquot of the derivatized extract was injected into the column (HP5-MS capillary column, 5% phenyl-95% methylsiloxane, 30 m x 0.25 mm I.D., 0.25 microm film thickness) of a Hewlett-Packard (Palo Alto, CA, USA) gas chromatograph (6890 Series). Methenolone was detected by its parent ion at m/z 446 and daughter ions at m/z 208 and 195 through a Finnigan TSQ 700 MS-MS system. The assay was capable of detecting 1 pg/mg of methenolone when approximately 100 mg hair material was processed. Linearity was observed for methenolone concentrations ranging from 2 to 100 pg/mg with a correlation coefficients of 0.965-0.981. Intra-day and between-day precisions at 2, 10 and 25 pg/mg were 10.9-14.1% and 13.7-16.8%, respectively, with an extraction recovery of 97.6%. The analysis of a strand of hair obtained from two bodybuilders, revealed the presence of methenolone at the concentrations of 7.3 and 8.8 pg/mg.

Anabolic Agents↗