Comparison of concentrations of drugs between blood samples with and without fluoride additive-important findings for Δ9-tetrahydrocannabinol and amphetamine.

Fluoride is a common stabilizing agent in forensic toxicology to avoid the frequent problem of degradation of drugs in blood samples especially described for cocaine. In cases only samples with addition of fluoride are available, it is a crucial question if also concentrations of common drugs other than cocaine (amphetamines, opiates and cannabinoids) are affected by fluoride. So far, there are only rare literature data available on discrepant results especially for Δ9-tetrahydrocannabinol (THC). In this study, comparative analysis of positive tested paired routine plasma/serum samples (n = 375), collected at the same time point (one device with and one without fluoride), was carried out with special focus on cannabinoids. Samples were measured with validated routine liquid chromatography-tandem mass spectrometry methods for THC, 11-hydroxy-THC (THC-OH), 11-nor-9-carboxy-THC (THC-COOH), cocaine, benzoylecgonine, ecgonine methyl ester, morphine, codeine, amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxyamphetamine, and 3,4-methylenedioxyethylamphetamine, and results were statistically evaluated. Beside the expected stabilization effect on cocaine and the consequently reduced concentration of ecgonine methyl ester in fluoride samples, benzoylecgonine was elevated compared to respective samples without fluoride. Most importantly, new findings were significantly reduced mean concentrations of THC (- 17%), THC-OH (- 17%), and THC-COOH (- 22%) in fluoride samples. Mean amphetamine concentration was significantly higher in samples with the additive (+ 6%). For the other amphetamine type of drugs as well as for morphine and codeine, no significant differences could be seen. Whenever specified thresholds have been set, such as in most European countries, the use of different blood sample systems may result in a motorist being differently charged or prosecuted. The findings will support forensic toxicologists at the interpretation of results derived from fluoride-stabilized blood samples.

Postoperative Hyperglycemia and 4-Year Neurodevelopmental Outcome in Children Operated for Congenital Heart Disease.

OBJECTIVES: To study the long-term neurodevelopmental effects of hyperglycemia in infant bypass surgery for congenital heart disease (CHD). STUDY DESIGN: Prospective cohort study on neurodevelopmental outcome after infant cardiac bypass surgery. EXCLUSION CRITERIA: age older than 1 year at first surgery, genetic comorbidity, and birth weight <2000 g. Of 167 eligible infants, follow-up examination at 4 years was completed in 150 children (90%). Intraoperative and postoperative highest and lowest glucose levels within 24 hours after bypass surgery were prospectively collected. Neurodevelopmental outcome at 4 years of age was assessed using standardized IQ tests and the Movement Assessment Battery for Children-second version for motor outcome assessment. RESULTS: Mean age at surgery was 2.8 months (0.1-10.7 months), 33% of children had an acyanotic CHD and 67% a cyanotic CHD. Glucose levels were elevated (>8 mmol/L) in 21 (14%) children in the first 24 postoperative hours. Glucose levels normalized in all children within 48 hours, 7 children (4%) received insulin infusions. Mean total IQ was within the normal range, but significantly lower than the normal population (92.5 [SD 15.0], P < .001). Higher postoperative glucose levels were related to better cognitive performance in the univariate analysis (P < .03), but not when other risk factors were taken into account. Independent risk factors for adverse outcome were lower socioeconomic status, higher risk adjustment for congenital heart surgery score, and longer duration of intensive care stay. CONCLUSION: Hyperglycemia is common in the early postoperative course after infant bypass surgery for CHD and normalizes within 48 hours. Hyperglycemia has no adverse effect on long-term neurodevelopmental outcome.

A detailed examination of platelet function inhibition by nitric oxide in platelet-rich plasma and whole blood.

BACKGROUND: The question of whether novel instruments such as multiple electrode aggregometry (MEA) can be used for measurement of the effects of nitric oxide (NO) on platelets (PLTs) has not been examined. METHODS: Therefore, we compared the effects of NO concentrations (1, 10, and 100 microM) on the PLT aggregation response to ADP, arachidonic acid (AA), collagen, ristocetin, and thrombin receptor-activating peptide 6 (TRAP6) using light transmission aggregometry (LTA) and multiple electrode aggregometry (MEA) and examined the effects of NO using the platelet function analyzer (PFA)-100. RESULTS: The response of PLTs to ADP and AA was strongly inhibited by all NO concentrations in LTA and MEA. The inhibition of the responses to ristocetin and collagen was detectable in MEA at lower NO concentrations than in LTA. However, the typically increasing lag phase between collagen addition and the aggregation response in the presence of NO was more obvious in LTA. TRAP caused a reproducible early response in the presence of NO in LTA which was followed by rapid PLT disaggregation, whereas even 100 microM NO did not inhibit the response to TRAP in MEA. Finally, NO prolonged the in-vitro bleeding time remarkably more in the PFA-100 collagen-epinephrin cartridge than in the collagen-ADP cartridge. CONCLUSIONS: Whole blood versus PLT rich plasma, citrate versus hirudin, and high versus low shear influenced the effects of NO. This shows that a careful selection of models and potentially a combination of different methods is appropriate for a differentiated evaluation of pharmacological or physiological mechanisms of NO-donors or of NO-inhibitors.

Unexpected results found in larvae samples from two postmortem forensic cases.

PURPOSE: In forensics, entomological specimens can be used as additional/alternative matrices to detect xenobiotics when human specimens are limited in their application. Despite some advantages over implementing putrefied human remains, most medico-legal laboratories do not include entomotoxicological procedures as routine analytical methods. We thus applied two authentic cases to evaluate necrophagous larvae's potential as complementary matrices for toxicological analysis after extensive postmortem decomposition. METHODS: Larvae and postmortem human samples, including hair, stomach contents, pericardial fluid, liver, lung, and skeletal muscle, were collected at autopsy. Samples were analyzed by liquid chromatography-tandem mass spectrometry and liquid chromatography-quadrupole time-of-flight mass spectrometry for pharmaceutical substances, illicit drugs, and new psychoactive substances, including synthetic cannabinoids, benzodiazepines, new synthetic opioids, and stimulants. RESULTS: Nearly all substances detected in human specimens, including several benzodiazepines and synthetic cannabinoids, were also detected in larvae. Surprisingly, some drugs, including the new psychoactive substances EAM-2201 and U-47700, were found exclusively in larvae and hair. The benzodiazepine etizolam was detected only in liver, lungs, and stomach contents, possibly resulting from characteristic tissue distribution in humans and/or larvae. CONCLUSIONS: Antemortem external hair contamination with synthetic cannabinoids from side-stream smoke and postmortem hair contamination with substances in putrefaction fluids can be supposed in these cases. Our findings suggest that supplementary information can indeed be gained from analyzing larvae additional to those human specimens that are typically used for toxicological analysis after extensive postmortem decomposition. Nevertheless, these results represent merely two cases, requiring in-depth studies to determine whether such findings can identify acute intoxications as possible causes of death.

Oral everolimus inhibits neointimal proliferation in prosthetic pulmonary valved stents in pigs.

BACKGROUND AND AIM OF THE STUDY: Growth factor-dependent cell proliferation can cause in-stent neointimal hyperplasia. The study aim was to evaluate whether oral everolimus inhibits the intimal proliferation associated with the implantation of prosthetic pulmonary valved stents. METHODS: Prosthetic pulmonary valves were implanted in 12 pigs (mean bodyweight 25 kg) using a transcatheter technique. Tricuspid valves were prepared from a titanium-coated polymer and sewn into a self-expanding nitinol stent (diameter 20 mm). Valved stents were implanted in the pulmonary position, where they remained for three months. In six animals, treatment with 2 mg/kg everolimus (Certican; Novartis) per day was started three days before implantation and continued throughout the course of the experiment. The other six pigs acted as controls. Adjuvant anticoagulation treatment consisted of acetylsalicylic acid and oral clopidogrel. After three months, hemodynamic valve function was investigated at catheterization and with MRI. At postmortem investigation the valved stents were explanted and subjected to macroscopic, histological and electron microscopic examination. RESULTS: There were no adverse side effects due to everolimus treatment. The overall mean everolimus plasma level during the study was 4.2 +/- 2.4 ng/ml. MRI revealed intact valve function with a regurgitation fraction of 7.3 +/- 4.2% in controls and 4.3 +/- 3.1% in the everolimus group (p <0.01). On macroscopic inspection and histological examination, the everolimus group showed only a thin tissue coverage of the stent struts. The valve cusps were free from intimal thickening, and electron microscopy showed a thin continuous cellular coating. In contrast, substantial neointimal formation was noted in controls. Tissue neogenesis was pronounced at the base of the valve, extended to the valve cusps, and caused valve thickening and foreshortening. CONCLUSION: The oral administration of everolimus effectively inhibits tissue neogenesis in pulmonary valved stents in pigs.

Single- and two-photon imaging of human micrometastases and disseminated tumour cells with conjugates of nanobodies and quantum dots.

Early detection of malignant tumours and, especially, micrometastases and disseminated tumour cells is still a challenge. In order to implement highly sensitive diagnostic tools we demonstrate the use of nanoprobes engineered from nanobodies (single-domain antibodies, sdAbs) and fluorescent quantum dots (QDs) for single- and two-photon detection and imaging of human micrometastases and disseminated tumour cells in ex vivo biological samples of breast and pancreatic metastatic tumour mouse models expressing human epidermal growth factor receptor 2 (HER2) or carcinoembryonic antigen (CEA). By staining thin (5-10 µm) paraffin and thick (50 µm) agarose tissue sections, we detected HER2- and CEA-positive human tumour cells infiltrating the surrounding tissues or metastasizing to different organs, including the brain, testis, lung, liver, and lymph nodes. Compared to conventional fluorescently labelled antibodies the sdAb-HER2-QD and sdAb-CEA-QD nanoprobes are superior in detecting micrometastases in tissue sections by lower photobleaching and higher brightness of fluorescence signals ensuring much better discrimination of positive signals versus background. Very high two-photon absorption cross-sections of QDs and small size of the nanoprobes ensure efficient imaging of thick tissue sections unattainable with conventional fluorescent probes. The nanobody-QD probes will help to improve early cancer diagnosis and prognosis of progression by assessing metastasis.

Magnetic resonance imaging-guided balloon angioplasty of coarctation of the aorta: a pilot study.

BACKGROUND: MRI guidance of percutaneous transluminal balloon angioplasty (PTA) of aortic coarctation (CoA) would be desirable for continuous visualization of anatomy and to eliminate x-ray exposure. The aim of this study was (1) to determine the suitability of MRI-controlled PTA using the iron oxide-based contrast medium Resovist (ferucarbotran) for catheter visualization and (2) to subsequently apply this technique in a pilot study with patients with CoA. METHODS AND RESULTS: The MRI contrast-to-noise ratio and artifact behavior of Resovist-treated balloon catheters was optimized in in vitro and animal experiments (pigs). In 5 patients, anatomy of the CoA was evaluated before and after intervention with high-resolution respiratory-navigated 3D MRI and multiphase cine MRI. Position monitoring of Resovist-treated catheters was realized with interactive real-time MRI. Aortic pressures were continuously recorded. Conventional catheterization was performed before and after MRI to confirm interventional success. During MRI, catheters filled with 25 micromol of iron particles per milliliter of Resovist produced good signal contrast between catheters and their background anatomy but no image distortion due to susceptibility artifacts. All MRI procedures were performed successfully in the patient study. There was excellent agreement between the diameters of CoA and pressure gradients as measured during MRI and conventional catheterization. In 4 patients, PTA resulted in substantial widening of the CoA and a decrease in pressure gradients. In 1 patient, PTA was ineffective. CONCLUSIONS: The MRI method described represents a potential alternative to conventional x-ray fluoroscopy for catheter-based treatment of patients with CoA.

Two fatalities associated with synthetic opioids: AH-7921 and MT-45.

In this study, two fatalities associated with the synthetic opioids AH-7921 and MT-45 are reported. Within the last few years, both compounds have emerged on the recreational drug market and are sold as "research chemicals" on the internet. In the first case, a 22-year-old woman was found dead in the bedroom of her apartment by two of her friends. A plastic bag labeled "AH-7921" was found in the apartment and the two friends stated that the deceased had consumed AH-7921 prior to her death. The woman was a known drug addict. In the second case, a 24-year-old man was found dead in his room by his mother. The deceased was sitting on a chair in front of his desk slumped over. Several bags of white powder labeled "MT-45", "Methoxmetamine" and "Methoxphenidine" were found in his room. Toxicological analyses of femoral blood, heart blood, liver, pericardial fluid, urine, vitreous humor and stomach content of the deceased were performed using liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS). Time-of-flight mass spectrometry was carried out on an LC-Triple TOF 5600 system (AB Sciex) with electrospray ionization operated in positive mode. In the first case, additional hair analysis was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and LC-QTOF-MS. In both cases, the relevant synthetic opioid could be detected in all analyzed samples. The concentration of AH-7921 was determined to be 450µg/L in femoral blood. MT-45 was present at a concentration of 2900µg/L in femoral blood. Besides methoxmetamine which could qualitatively be detected in femoral blood, urine and stomach content no methoxphenidine was found. In summary, deaths of the young individuals could be, by exclusion of other causes of death, attributed to the consumption of an overdose of AH-7921 and MT-45, respectively.

Hypothermic protection of the ischemic heart via alterations in apoptotic pathways as assessed by gene array analysis.

Hypothermia improves resistance to ischemia in the cardioplegia-arrested heart. This adaptive process produces changes in specific signaling pathways for mitochondrial proteins and heat-shock response. To further test for hypothermic modulation of other signaling pathways such as apoptosis, we used various molecular techniques, including cDNA arrays. Isolated rabbit hearts were perfused and exposed to ischemic cardioplegic arrest for 2 h at 34 degrees C [ischemic group (I); n = 13] or at 30 degrees C before and during ischemia [hypothermic group (H); n = 12]. Developed pressure, the maximum first derivative of left ventricular pressure, oxygen consumption, and pressure-rate product (P < 0.05) recovery were superior in H compared with in I during reperfusion. mRNA expression for the mitochondrial proteins, adenine translocase and the beta-subunit of F1-ATPase, was preserved by hypothermia. cDNA arrays revealed that ischemia altered expression of 13 genes. Hypothermia modified this response to ischemia for eight genes, six related to apoptosis. A marked, near fivefold increase in transformation-related protein 53 in I was virtually abrogated in H. Hypothermia also increased expression for the anti-apoptotic Bcl-2 homologue Bcl-x relative to I but decreased expression for the proapoptotic Bcl-2 homologue bak. These data imply that hypothermia modifies signaling pathways for apoptosis and suggest possible mechanisms for hypothermia-induced myocardial protection.

Physical models aiding in complex congenital heart surgery.

PURPOSE: Our aim was to improve spatial imagination of complex congenital cardiac abnormalities for subsequent surgical intervention. DESCRIPTION: Magnetic resonance imaging data of a patient with complex congenital heart malformations was post-processed with software developed at our institution. The resulting virtual surface data sets were printed out three-dimensionally by rapid prototyping techniques. EVALUATION: We present the first patient operated on with intraoperative use of physical models representing the intracardiac volumes (RepliCast) or muscle and vessel walls (RepliCardio). The courses of the coronary arteries were visible on the RepliCast, whereas the RepliCardio showed intracardiac views a surgeon could never obtain intraoperatively in the relaxed heart. Other than on virtual reconstructions presented on computer screens, physical models vastly improve the spatial imagination and give precise information regarding localization and actual size of abnormal structures. The self-explanatory utility of these models shortened preparation and expedited orientation on the open heart. CONCLUSIONS: The additional spatial information provided by RepliCast and RepliCardio models may enable even high-risk correction procedures in patients with complex congenital heart disease.

Direct action of T3 on phosphorylation potential in the sheep heart in vivo.

Thyroid acting through ligand binding to nuclear receptors modifies myocardial respiratory kinetics and oxidative phosphorylation in the heart. Direct nongenomic action of thyroid hormone on high-energy phosphate concentrations and respiratory kinetics has never been proven in vivo but might be responsible for observed changes in oxygen utilization efficiency immediately after triiodothyronine (T3) administration. We tested the hypothesis that T3 directly and rapidly modifies myocardial high-energy phosphate concentrations and phosphorylation potential in vivo. Anesthetized sheep (age 28-40 days) thyroidectomized shortly after birth (Thy) and euthyroid age-matched controls (Con) underwent median sternotomy and received T3 infusion (0.8 microg/kg), followed by epinephrine infusion to increase myocardial oxygen consumption (MVo2). 31P magnetic resonance spectra were monitored via a surface coil over the left ventricle. T3 increased phosphocreatine (PCr)/ATP and decreased ADP in Thy animals without causing a change in MVo2. T3 produced no changes in high-energy phosphates in Con animals. T3 did not modify the PCr/ATP or ADP response to epinephrine and elevation in MVo2 in either group. Cardiac mitochondria isolated from Thy and Con animals showed no change in respiratory rate or ADP/ATP exchange efficiency after T3 incubation. T3 infusion in a hypothyroid state decreases ADP concentration, thereby altering the equilibrium between phosphorylation potential and myocardial respiratory rate. These T3-induced effects are not due to changes in ADP/ATP exchange efficiency through action at the adenine nucleotide translocator but may be due to T3 mediation of substrate utilization, confirmed in other models.

Hypothermia preserves myocardial function and mitochondrial protein gene expression during hypoxia.

Hypothermia before and/or during no-flow ischemia promotes cardiac functional recovery and maintains mRNA expression for stress proteins and mitochondrial membrane proteins (MMP) during reperfusion. Adaptation and protection may occur through cold-induced change in anaerobic metabolism. Accordingly, the principal objective of this study was to test the hypothesis that hypothermia preserves myocardial function during hypoxia and reoxygenation. Hypoxic conditions in these experiments were created by reducing O2 concentration in perfusate, thereby maintaining or elevating coronary flow (CF). Isolated Langendorff-perfused rabbit hearts were subjected to perfusate (Po2 = 38 mmHg) with glucose (11.5 mM) and perfusion pressure (90 mmHg). The control (C) group was at 37 degrees C for 30 min before and 45 min during hypoxia, whereas the hypothermia (H) group was at 29.5 degrees C for 30 min before and 45 min during hypoxia. Reoxygenation occurred at 37 degrees C for 45 min for both groups. CF increased during hypoxia. The H group markedly improved functional recovery during reoxygenation, including left ventricular developed pressure (DP), the product of DP and heart rate, dP/dtmax, and O2 consumption (MVo2) (P < 0.05 vs. control). MVo2 decreased during hypothermia. Lactate and CO2 gradients across the coronary bed were the same in C and H groups during hypoxia, implying similar anaerobic metabolic rates. Hypothermia preserved MMP betaF1-ATPase mRNA levels but did not alter adenine nucleotide translocator-1 or heat shock protein-70 mRNA levels. In conclusion, hypothermia preserves cardiac function after hypoxia in the hypoxic high-CF model. Thus hypothermic protection does not occur exclusively through cold-induced alterations in anaerobic metabolism.