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Caffeine, 1,3,7-trimethylxanthine, is the most widely consumed legal stimulant. The most potent form is over the counter oral tablets. The estimated average daily adult caffeine consumption is 300 mg. Rarely, serious toxicities such as seizure and cardiac arrhythmias have caused death. Caffeine concentrations of 80 mg/L are considered lethal. Cases investigated over 10 years by the Office of the Chief Medical Examiner for the State of Maryland ( OCME) whose cause of death was solely or in combination due to caffeine intoxication were reviewed. A total of eight adult cases were identified consisting of two suicides and six undetermined manners. The average postmortem caffeine concentration was 140.4 mg/L. This is the largest case series reported to date of lethal caffeine intoxication. Large doses of prescription medications and/or over the counter medications were abused. No overdoses were from consumption of caffeine-containing foods. Comprehensive postmortem toxicological testing should test for caffeine to capture these rare deaths. [ABSTRACT FROM AUTHOR]

Cathinone derivatives (bath salts) have emerged as the latest drugs of abuse. 3,4-methylenedioxypyrovalerone ( MDPV) is the primary active ingredient in bath salts used in this country. This article presents the second reported cause of death by MDPV intoxication alone. In April 2011, a delusional man was emergently brought to a hospital, where he self-reported bath salt usage. He became agitated, developed ventricular tachycardia, hyperthermia, and died. Comprehensive alcohol and drug testing was performed. Using the alkaline drug screen, heart blood contained 0.7 mg/L MDPV and peripheral blood contained 1.0 mg/L MDPV. His bizarre behavior with life-threatening hyperthermia was consistent with an MDPV-induced excited delirium state. MDPV is not yet found by routine immunoassay toxicology screens. Testing for MDPV should be considered in cases with a history of polysubstance abuse with stimulant type drugs, report of acute onset of psychogenic symptoms, excited delirium syndrome, or presentation in a hyperthermic state. [ABSTRACT FROM AUTHOR]

Neuroblastoma is the most common extracranial solid malignancy in children. The disease possesses a broad range of clinical phenotypes with widely varying prognoses. Numerous studies have sought to identify the associated genetic abnormalities in the tumour, resulting in the identification of useful prognostic markers. In particular, the presence of multiple copies of the MYCN oncogene (referred to as MYCN amplification) has been found to confer a poor prognosis. However, the molecular pathways involved are as yet poorly defined. Metabolite profiles generated by in vitro 1H MRS provide a means of investigating the downstream metabolic consequences of genetic alterations and can identify potential targets for new agents. Thirteen neuroblastoma cell lines possessing multiple genetic alterations were investigated; seven were MYCN amplified and six MYCN non-amplified. In vitro magic angle spinning 1H MRS was performed on cell suspensions, and the spectra analysed to obtain metabolite concentration ratios relative to total choline (tCho). A principal component analysis using these concentration ratios showed that MYCN-amplified and non-amplified cell lines form separate classes according to their metabolite profiles. Phosphocholine/tCho and taurine/tCho were found to be significantly raised ( p < 0.05) and glycerophosphocholine/tCho significantly reduced ( p < 0.05) in the MYCN-amplified compared with the MYCN non-amplified cell lines (two-tailed t test). 1H MRS of the SH-EP1 cell line and an isogenic cell line transfected with the MYCN oncogene also showed that MYCN oncogene over-expression causes alterations in phosphocholine, glycerophosphocholine and taurine concentrations. Molecular pathways of choline and taurine metabolism are potential targets for new agents tailored to MYCN-amplified neuroblastoma. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Peptides corresponding to the N-terminus of skeletal myosin light chain 1 (rsMLC1 1–37) and the short loop of human cardiac β-myosin (hcM398–414) have been shown to interact with skeletal F-actin by NMR and fluorescence measurements. Skeletal tropomyosin strengthens the binding of the myosin peptides to actin but does not interact with the peptides. The binding of peptides corresponding to the inhibitory region of cardiac troponin I (e.g. hcTnI128–153) to F-actin to form a 1 : 1 molar complex is also strengthened in the presence of tropomyosin. In the presence of inhibitory peptide at relatively lower concentrations the myosin peptides and a troponin I peptide C-terminal to the inhibitory region, rcTnI161–181, all dissociate from F-actin. Structural and fluorescence evidence indicate that the troponin I inhibitory region and the myosin peptides do not bind in an identical manner to F-actin. It is concluded that the binding of the inhibitory region of troponin I to F-actin produces a conformational change in the actin monomer with the result that interaction at different locations of F-actin is impeded. These observations are interpreted to indicate that a major conformational change occurs in actin on binding to troponin I that is fundamental to the regulatory process in muscle. The data are discussed in the context of tropomyosin's ability to stabilize the actin filament and facilitate the transmission of the conformational change to actin monomers not in direct contact with troponin I. [ABSTRACT FROM AUTHOR]

Investigates the involvement of the cytoplasmic region of phospholamban in interaction with the calcium-activated ATPase of the sarcoplasmic reticulum (SERCA). Reduction of the affinity of the peptide for the pump by phosphorylation of Ser16; C-terminal regions of both peptides; Segments of the cytoplasmic domain of SERCA.

Examines the relationship of plasma buprenorphine and norbuprenorphine concentrations with withdrawal symptomatology during buprenorphine dose induction, maintenance treatment and withdrawal. Identification of the two opioid agonist substitution medications that were approved by the United States Food and Drug Administration; Information on the use of methadone in treating opioid dependence; Methodology used in the examination.

Nuclear magnetic resonance and electron paramagnetic resonance spectroscopy have been used to quantify metal binding to the phosphoprotein extractable from demineralized rat incisor dentine. Paramagnetic cation probes enable identification of the metal binding sites. Cations are able to diffuse across the protein surface while forming a relatively long-lived metal-phosphoprotein complex. The ability of the protein to sequester surface-mobile Ca(II) is discussed in terms of its ability to act as a possible nucleation site for the initial localization of Ca(II) within the dentine matrix. [ABSTRACT FROM AUTHOR]

The interaction between actin and caldesmon that is associated with the inhibition of actomyosin ATPase activity in smooth muscle has been studied using 1H-NMR spectroscopy. Binding studies using the intact molecules were complemented by the use of thrombic cleavage fragments of both turkey and chicken gizzard catdesmon as well as defined peptides of actin, in order to investigate the conformational properties of caldesmon and to localise regions of the primary structures that participate in protein-protein contacts. The binding of caldesmon is shown to involve distinct segments on the N-terminal region (residues 1 – 44) of actin, as previously observed for the inhibitory component of the thin filament of striated muscle, troponin I [Levine et al. (1988) Eur. J. Biochem. 153, 389 – 397]. The comparable structural properties of these tissue-specific inhibitors of actomyosin ATPase and the similarities in their mode of interaction at the N-terminal region of actin suggest common aspects to the structural mechanism for thin-filament regulation in smooth and striated muscle. Unlike the inhibitory interaction of troponin I, however, the binding of caldesmon to the N-terminal region of actin directly involves groups within residues 20 – 41 of actin that are also recognised by myosin subfragment 1. The complementary segment of caldesmon has been localised to a 15-kDa thrombic fragment (residues 483 – 578) derived from the N-terminal portion of a 35-kDa cleavage product from the C-terminal of caldesmon whose interaction with actin is modulated by calmodulin. The results are discussed in relation to the calcium-mediated mechanism for thin- filament regulation in smooth and striated muscle. [ABSTRACT FROM AUTHOR]

The interaction between troponin-I and actin that underlies thin-filament regulation in striated muscle has been studied using proton magnetic resonance spectroscopy. A restricted portion of skeletal muscle troponin-I (residues 96-116) has previously been shown to be capable of inhibiting the MgATPase activity of actomyosin in a manner enhanced by tropomyosin [Syska et al. (1976) Biochem. J. 153, 375-387]. On the basis of homologous spectral effects for signals of specific groups observed in different complexes formed using the native proteins and a variety of defined peptides, it is concluded that the segment of troponin-I which has inhibitory activity interacts with the N-terminal region of actin, The surface of contact of the inhibitory segment of troponin-I with actin involves two regions of the N-terminal of actin. These are located between residues 1-7 and 19-44. The data are discussed in the context of a structural mechanism for the inhibition of myosin ATPase activation. [ABSTRACT FROM AUTHOR]

Reports on an analysis of [sup 1]hydrogen-nuclear magnetic resonance spectroscopic techniques of the conformation of the nitrogen terminal segment of the LC1 alkali light chain of rabbit skeletal muscle which has shown that this portion of the molecule adopts a well-defined elongated configuration. Finding that the rod-like feature is a consequence of the Ala/Pro-rich composition and discussion of the functional aspects of such conformational preference in this and similar segments in other proteins.

1HNMR is used to study the solution structure o f vitamin-D-induced bovine intestinal calcium-binding protein. The study of the native protein is aided by the recently published crystal structure; it is shown that the conformations of the molecule in the crystal and in solution are very similar. The effect of pH and temperature on the native structure is described. The structure of the apo protein is then described, and the effect of pH and temperature on its fold is outlined. A comparison between apo and native protein binds is made which indicates that the folds are very similar. The two folds are related by a calcium titration, which indicates that the protein binds two calcium ions sequentially, Both steps in the Ca2+ titration occur under conditions of slow exchange (kex 80s-1). The effect of binding Ca2+ ions is to cause twisting motions of helices, with the helices acting as rods, relaying the conformational change induced by Ca2+ binding to the linker regions of the protein. [ABSTRACT FROM AUTHOR]

Proton magnetic resonance spectroscopy has been used to study the cation(Mg2+ , Ca2+)-dependent conformational states of the C-terminal domain of rabbit skeletal troponin C under a variety of solution conditions. Nuclear Overhauser data and paramagnetic probe observations provide definition of the configuration of this region of troponin C. Comparative study of homologous proteins identify common features of the tertiary structure relevant to the biding reaction. Complex formation with troponin I and the drug intercative conformational response to cation coordination and the binding of the drug and troponin I are discussed. [ABSTRACT FROM AUTHOR]

Identical tripeptides of the sequence X-Pro-Lys, where X is an unknown blocking group, were isolated from trypsin digests of bovine cardiac alkali light chain and the LC2 light chain of rabbit fast muscle. Chemical, electrophoretic and ¹H-NMR evidence characterized X as an unusual amino acid, α-N-trimethylalanine (Me3Ala), which was earlier reported as the N-terminal amino acid of the A1 alkali light chain of rabbit fast muscle [Henry et al. (1982) FEBS Lett. 144, 11–15]. The narrow Line width and chemical shift position (δ = 3.23 ppm) of the -N+-(CH3) protons of Me3Ala made ¹H-NMR spectroscopy a convenient method to search for this residue in other light chains. A survey of many different light chains showed that tiffs signal was present in all vertebrate striated muscle light chains of the A1-type (LC1, ‘essential’ light chains) and LC2-type (‘DTNB’-light chains, ‘phosphorylatable’ light chains) but was absent from all invertebrate muscle and vertebrate smooth muscle light chains tested. It was also absent from the vertebrate fast-muscle-specific A2-type (LC3) light chains. The spectral characteristics of these signals were consistent with their having arisen from the protons of an -N+-(CH3)3 grouping. Since no ε-trimethyllysine could be detected in acid hydrolysates of these proteins, it appears that Me3Ala is a general feature as the N-terminal amino acid in these light chains. ¹H-NMR studies on bovine cardiac myosin subfragment 1 (S1) showed that the Me3Ala methyl proton signal was clearly visible and that the spectrum more closely resembled that of a rabbit S1 isoenzyme, S1(A1), than S1(A2), suggesting that the 40-residue N-terminal segment of the alkali light chain in cardiac S1 also possesses a high segmental mobility. Addition of actin caused the same gross changes to the cardiac S1 spectrum as noted earlier for rabbit S1(A1) [Prince et al. (1981) Eur. J. Biochem. 121, 213–219]. In particular, a marked reduction in the segmental mobility of the N-terminal region of the alkali light chain was noted, consistent with a direct interaction of this area with actin. [ABSTRACT FROM AUTHOR]

Using assignments of resonances in the 1H NMR spectrum of calmodulin obtained by the use of large tryptic fragments of the molecule [Dalgarno, D. C., Klevit, R. E., Levine, B. A., Williams, R. J. P., Dobrowolski, Z., and Drabikowski, W. (1984) Eur. J. Biochem. 138, 281–289], the spectral changes which occur on Ca2+ binding to calmodulin have been examined in detail. Ca2+ binding occurs in two stages: the first two Ca2+ ions bind at sites III and IV (numbered from the N terminus) and the second two Ca2+ ions bind at sites I and II. The high-affinity binding causes perturbations of residues in both halves of the molecule, whereas binding at the two N-terminal sites only affects sidechains in that half of the molecule. The effects of binding Cd2+ to the Ca2+-binding sites of calmodulin have also been studied by 1H NMR. The cation induces spectral changes which are very similar to those seen for Ca2+, but some important differences do exist. [ABSTRACT FROM AUTHOR]

Two tryptic fragments of the Ca2+-binding protein calmodulin have been studied by high-resolution 1H NMR. TR1C (residues 1 – 77) spans the first two domains of the protein and TR2C (residues 78 – 148) spans the second two domains. The spectra indicate that each of the two-domain peptide assumes a conformation which is very close to that in the native protein. This characteristic holds both in the presence and in the absence of Ca2+ ions. Therefore, the resonance assignments obtained for the relatively simpler fragment spectra can be used to assign the spectrum of whole calmodulin. Analysis of the chemical shift patterns and nuclear Overhauser enhancement effects of several assigned resonances indicates that each half of calmodulin can be modeled after the two EF-Hand Ca2+-binding proteins for which crystal structures are available, namely parvalbumin and intestinal Ca2+ -binding protein. [ABSTRACT FROM AUTHOR]

High-resolution proton NMR spectrocopy has been used to study the solution structures of the subfragment 1 (S1) isoenzymes (containing either the A1 or A2 light chains) from rabbit skeletal muscle myosin and to investigate their interaction with actin. Superimposed upon broad components, the narrow signals of the S1 spectra are unexpectedly sharp, indicating that domains of varying sidechain mobility occur in the conformation adopted in solution. These observations are in agreement with previous studies of the mixed isoenzymes [Highsmith et al. (1979) Biochemistry, 18, 4238 -4243]. Peptide amide exchange studies show also that the S 1 structure accommodates fluctuations of sufficient amplitude to allow most of the peptide groups to come into contact with the solvent on the time scale,of the 1H-NMR experiment. The overall impression is that S1 is a molecule possessing backbone motility as well as domains of different sidechain mobility. Close comparison of the S1(A1) and S1(A2) spectra indicate that the N-terminal 41 residues of the Al light chain, rich in lysine, proline and alanine, display a high degree of segmental mobility. The difference spectrum [S1(A1)-S1(A2)] obtained closely resembles the spectral simulation of the 41 -residue segment. Upon addition of actin, many of the narrow S1 resonances decrease in intensity or progressively disappear altogether, indicative of intermediate-slow exchange conditions consistent with the recognised high affinity between the two proteins. These changes are interpreted as an overall modulation in the observed and hence more mobile regions of S1 as has been suggested in earlier 1H-NMR studies referred to above. In particular, the differences noted between S 1(A 1) and S 1(A2) have now largely disappeared in their complexes with actin indicating a marked reduction in the segmental mobility of the N-terminal region of the light chain in S 1(A 1). Together with other affinity chromatography results [Winstanley and Trayer (1979) Biochem. Soc. Trans. 7, 703-704], this is good evidence for a direct interaction between this area of S1(A1) and actin. [ABSTRACT FROM AUTHOR]

Surface chemical and nuclear magnetic resonance (NMR) techniques have been used to study the interaction of Ca2+ and lanthanides with lecithins. With both methods positive reactions were detected at metal concentrations > 0.1 mM. ¹H and 31P high-resolution NMR spectra obtained with single bilayer vesicles of lecithin were invariant up to Ca2+ concentrations of 0.1 M indicating that there is only a loose association between Ca2+ and the phospholipid. The weak interaction between Ca2+ and lecithin is confirmed by both surface chemical and NMR techniques showing that the packing of egg lecithin molecules present in bilayers does not change up to Ca2+ concentrations of about 0.1 M. The packing was also independent of pH between 1-10. Contradictory results have been reported in the literature concerning the question of Ca2+ binding to lecithins. The conflicting results are shown to have arisen from differences in the experimental conditions and differences in the sensitivity of the physical methods used by various authors to study Ca2+-lecithin interactions. An estimate of the strength of binding and molecular details of the interaction were derived using paramagnetic lanthanides as isomorphous replacements for Ca2+. From the changes in chemical shifts induced in the presence of lanthanides an apparent binding constant KA ≈ 30 l/mol was calculated at lanthanide concentrations > 10 mM. Using surface chemical methods it was shown that this KA is up to 10 times larger than that for Ca2+ binding. The complete assignment of the ¹H NMR spectrum of lecithin, including the resonances from the relatively immobilized glycerol group, was determined to derive molecular details of the cationlecithin interaction. From spin-lattice relaxation-time measurements and line broadening in the presence of GdCl3 it is concluded that the cations are bound to the phosphate group and that this is the only binding site. The absolute proton shifts induced by paramagnetic lanthanides depended on the nature of the ion, but the shift ratios standardised to the shift of the O3POCH2 (choline) signal were invariant throughout the lanthanide series indicating that the shifts are purely pseudocontact. In contrast the 31P shifts were found to contain significant contact contributions. These findings are consistent with a weak interaction and with the phosphate group being the binding site. The absolute shifts but not the shift ratios depended on the anion present indicating that the cation binding may be accompanied by binding of anions. Contrary to negatively charged phospholipids the interaction of lanthanides with lecithins was enhanced as the ionic strength was increased by adding NaCl. This was explained in terms of stearic hindrance due to the extended conformation of the lecithin polar group. [ABSTRACT FROM AUTHOR]

The pattern of phosphorylation of adjacent serine residues in several peptides based on the N-terminal region of human cardiac troponin I has been analysed by PAGE and H NMR spectroscopy to identify the products. With cAMP-dependent protein kinase, Ser24 is rapidly phosphorylated, and subsequent much slower phosphorylation of Ser23 occurs only after phosphorylation of Ser24 is almost complete. Monophosphorylation of the peptide al Ser23 was not detected at any time. On replacement of Arg22 with Ala or Met the sole phosphorylation target was Ser23, phosphorylation being considerably slower than for Ser24 in the wild-type peptide, while diphosphorylation could not be detected after prolonged incubation. The results emphasise the importance of the N-terminal sequence RRRSS for the function of cardiac troponin I and imply that in human cardiac muscle unstimulated by adrenaline, troponin 1 is phosphorylated on Ser24. Comparative two-dimensional NOESY data indicate that in the diphosphorytared form at physiological pH values, specific structural constraints are imposed on the N-terminal peptide region. These constraints result in the effective screening of the two phosphate groups from each other by the arginine residues N-terminal to the serine pair and stabilisation of the structure in the region of residues 25-29, which is adjacent to a site of interaction between troponin I and troponin C. These conformational changes presumably underlie the decrease in calcium sensitivity of the myofibrillar ATPase that occurs after adrenaline intervention. [ABSTRACT FROM AUTHOR]

1H-NMR and circular dichroism studies have been carried out on osteocalcin, a 49-residue, calcium-binding protein, the sequence of which contains a disulphide bridge, a proline-rich segment and three γ-carboxyglutamic acid (Gla) residues. These latter residues have been proposed to lie on one face of an alpha helix and interact with the mineral phase, leading to incorporation of the protein into the bone matrix. Circular dichroism shows an increase in the alpha-helical structure on Ca2+ binding to bovine osteocalcin. This induced structure is lost on heating the protein, giving a spectrum close to that of the Ca2+-free protein. 1H-NMR studies of rabbit osteocalcin gave a set of resonance assignments and NOEs which could be interpreted in terms of distance constraints. These did not allow a single conformation to be defined for the protein in solution but reflect rather a flexible structure which may be essential for the function of the protein. The calculated structures contain a hydrophobic core (comprising Leu2, Leu32, Val36 and Tyr42, seen to be slowly flipping in the Ca2+-bound form) and have the γ-carboxyglutamic acid side chains exposed on one face of the molecule. [ABSTRACT FROM AUTHOR]

Using NMR spectroscopy to visualise tyrosine phosphorylation kinetics in real time, we have investigated the sequence-dependent determinants of the selectivity of the human insulin receptor protein-tyrosine kinase for different tyrosine residues. The peptides used encompass the multipletyrosine-containing autophosphorylation site sequences from the itisulin receptor kinase core domain (Tyr1158, Tyr1162 and Tyr1163) and from its specific C-terminal tail domain (Tyr1328 and Tyr1334). Comparison of the phosphorylation kinetics with those found for the tyrosine residues on a peptide comprising the regulatory tyrosine phosphorylation site of cdc2 points to the role of the primary sequence context of the phosphate acceptor. The particularly deleterious influence of a basic residue immediately C-terminal to the tyrosine is discussed in relation to the autophosphorylation properties of the regulatory loop regions of the insulin and epidermal growth factor receptor kinases. The data further suggest that receptor tyrosine kinase active sites and their substrate targets act in concert to ensure that specific downstream effects are activated. [ABSTRACT FROM AUTHOR]

[sup1]H-NMR and 31P-NMR spectroscopy were employed to assess the electrostatic consequences of phosphorylation of single and multiple tyrosine residues in peptides derived from the core and tail autophosphorylation regions of the human insulin receptor tyrosine-kinase domain. In both peptides, phosphorylation was accompanied by changes in the resonances from basic side-chains; those from acidic residues were unaffected. Tyrosine phosphorylation caused increases of up to one in the pK[suba] values of histidine residues situated up to eight residues away in the primary sequence. Titration curve analysis by Hill plots suggested some cooperatively of histidine and phosphate ionizations. Behavior closely analogous to that of the insulin receptor tail peptide was observed during changes in phosphorylation of the intact insulin receptor kinase domain, suggesting that the electrostatic dissemination effects seen for the isolated peptide are retained by the peptide sequence in the context of the much larger protein. Similar changes in the behavior of basic residues were also observed upon tyrosine phosphorylation of a cdc2-derived peptide, suggesting that this potential of phosphorylation events to propagate directed structural changes may find a widespread utility in the activation of protein kinases and in the transduction of phosphorylation-based signaling. [ABSTRACT FROM AUTHOR]

Earlier 1H-NMR experiments on the myosin subfragment-1 (S1) light chain isoenzymes from rabbit fast muscle, containing either the A1 or the A2 alkali light chains [S1(A1) or S1(A2)], have shown that the 41-residue N-terminal extension of A1, rich in proline, alanine and lysine residues, is freely mobile in solution but that this mobility is constrained in the acto-S1(A1) complex [Prince et al. (1981) Eur. J. Biochem. 121,213–219]. It is now established that this N-terminal region of the A l-light chain interacts directly with the C-terminal region of actin in the acto-Sl (A1) complex. This was shown by covalently labelling the Cys-374 residue of actin with a spin-label and observing the enhanced relaxation this paramagnetic centre induced in the 1H-NMR spectrum of S1(A1). In particular, the signal arising from the -N+ (CH3)3 protons of α-N-trimethylalanine (Me3Ala) were monitored as this residue is uniquely sited at the N-terminus of the A1 light chain [Henry et al. (1982) FEBS Lett. 144, 11 — 15]. Experiments using complexes of actin with either the N-terminal 37-residue peptide of A1, S1 (A1) or heavy meromyosin indicate that the N-terminal region of A1 is binding in a similar manner to actin in each case, with the N-terminal Me3A1a residue within 1.5 nm of the spin label introduced to Cys-374 of actin. A similar strategy was adopted to show that the Me3Ala residue can also be found close (<1.5 rim) to the fast-reacting SH1 thiol group on the S1 heavy chain. These data, together with published work, have been used to suggest a possible organisation for the polypeptide chains in the myosin head. [ABSTRACT FROM AUTHOR]

Previous theoretical and empirical research on economic sociology leaves much to be desired in terms of consistently defining the agenda and objectives of the discipline As a result, economic sociology often appears to lack a clearly defined mission and purpose This is epitomized by various failures to establish adequate epistemological relations of the proper realm of economic sociology with those of economics and sociology, and especially with the domain of rational choice theory This failure is compounded by a misplaced distinction between the subject matter of economic sociology and that of sociological economics, or socioeconomics. And some recent works in the discipline (including the ambitious Handbook of Economic Sociology) have not helped to remedy this situation In this paper, we try to address this situation by suggesting some reformulations of the subject matter of economic sociology in relation to those of related disciplines In addition, we attempt to redefine the field of the sociology of the market which is seen as the focal specialty of economic sociology. [ABSTRACT FROM AUTHOR]

Cause of death rulings in cases when the concentration of a drug or drugs is higher than observed following therapeutic use are generally straightforward 'drug deaths.' However, when toxicology testing identifies drug concentrations consistent with therapeutic use or detects no drugs at all, then the cause of death determination is more complicated. Given the rapidity and protean manifestations of anaphylaxis, it should be considered in deaths where no other cause of death is apparent in a suspected drug death. This article reports two cases where an anaphylactic reaction was observed following either the actual or alleged use of therapeutic formulations of buprenorphine intravenously. [ABSTRACT FROM AUTHOR]

A previous study suggested that small amounts of morphine are metabolically converted to hydromorphone. In the present study, morphine positive urine specimens obtained from a postmortem laboratory and a random urinalysis program were tested for morphine, codeine, hydromorphone, hydrocodone, oxymorphone, and oxycodone to assess the possibility that small amounts of hydromorphone are produced from the metabolism of morphine. The opioids were analyzed by gas chromatography–mass spectrometry as their respective trimethylsilyl derivatives following solid phase extraction. The limit of detection for hydromorphone was 5 ng/mL. A total of 73 morphine positive urine specimens were analyzed, with morphine concentrations ranging from 131 to 297,000 ng/mL. Hydromorphone was present at a concentration ≥5 ng/mL in 36 of these specimens at concentrations ranging from 0.02% to 12% of the morphine concentration. Hydrocodone was not detected in these specimens at the assay detection limit of 25 ng/mL. These results support earlier work suggesting that the detection of hydromorphone in urine specimens does not necessarily mean that exogenous hydromorphone or hydrocodone was used. [ABSTRACT FROM AUTHOR]

Describes a case of oxycodone intoxication in a 10-month old infant. Identification of oxycodone in postmortem specimens using gas chromatography-nitrogen phosphorus detection and confirmation by full scan electron ionization gas chromatography-mass spectrometry; Suggestion that there are serious concerns about the likelihood of drug exposure through consumption of breast milk.