Medical prescription forms of opioid cough suppressants falsified by the patients before and after they switched from over-the-counter to prescription-only in France.

AIMS: The French Ministry of Health scheduled opioid cough suppressants as prescription-only drugs on 12 July 2017. The present study assessed the impact of this regulation on the diversion modalities of the concerned drugs and the related drug pholcodine by analysing the national OSIAP (Ordonnances Suspectes Indicateur d'Abus Possible) database. METHODS: Medical prescriptions with at least 1 mention of codeine, dextromethorphan, ethylmorphine, noscapine or pholcodine for cough suppression recorded in 2013-2019 were extracted from OSIAP. Annual mentioning rates were estimated by dividing numbers of mentions over those of prescriptions recorded the year considered. A descriptive analysis compared the characteristics of prescriptions before and after 12 July 2017. RESULTS: Overall, 832 mentions of the requested drugs were retrieved on 827 prescription forms. Codeine was the most frequent (n = 809, 8.7%) with 6 additional mentions of codeine/ethylmorphine combination, followed by dextromethorphan (n = 11, 0.1%) and pholcodine (n = 6, 0.1%). There was no mention of noscapine. Annual mentioning rates varied between 0 and 0.3% for all drugs except codeine. Codeine mentioning rates ranged between 0.3% (n = 2) and 0.7% (n = 9) before 12 July 2017 and increased to 10.1% (n = 61) thereafter in 2017, 16.1% (n = 314) in 2018, and 19.8% (n = 414) in 2019. The profile of subjects evolved accordingly with an increased male/female ratio (10.0 vs. 1.5 before) and decreased age (23 vs. 40 y before, P < .001). DISCUSSION: The sharp increase of recourse to falsified prescription forms indicates that codeine diversion continues despite restricted access, whereas the other drugs studied do not seem to have been impacted.

Core in Cup Ethylmorphine Hydrochloride Tablet for Dual Fast and Sustained Pain Relief: Formulation, Characterization, and Pharmacokinetic Study.

Ethylmorphine hydrochloride (EtM) is a derivative of morphine used as analgesic to treat severe pain in case of cancer and bone injury. This study aimed to formulate and evaluate core in cup tablets containing 2 doses of EtM, the cup was formulated as lyophilized oro-dispersible tablet (ODT) for immediate release (IR), and the core was formulated as directly compressed tablet for sustained release (SR). Factorial design was adopted for the optimization of tablets prepared via lyophilized form and direct compression techniques: a 41.22 design was used for the former, while a 32 one was used for the latter. All prepared tablets showed acceptable physical properties which were in accordance with pharmacopeial standards. Two lyophilized ODTs (F9 and F10) formulae were selected as the cup for instant release. While one directly compressed tablet formula (S6) was selected based on the in vitro release profile to represent the sustained core, the outcome was 2 core in cup tablets, namely B1 and B2 which were evaluated for their in vivo absorption and showed a maximum plasma concentration (Cpmax) of 354.12 ± 17.55 ng/mL and 350.82 ± 12.15 ng/mL respectively attained after 3.0 h which were twofolds significantly higher in comparison to the market tablet with Cpmax of only 172.05 ± 12.53 ng/mL attained after 2.20 ± 0.24 h.

Can routine information from electronic patient records predict a future diagnosis of alcohol use disorder?

OBJECTIVE: To explore whether information regarding potentially alcohol-related health incidents recorded in electronic patient records might aid in earlier identification of alcohol use disorders. DESIGN: We extracted potentially alcohol-related information in electronic patient records and tested if alcohol-related diagnoses, prescriptions of codeine, tramadol, ethylmorphine, and benzodiazepines; elevated levels of gamma-glutamyl-transferase (GGT), and mean cell volume (MCV); and new sick leave certificates predicted specific alcohol use disorder. SETTING: Nine general practitioner surgeries with varying size and stability. SUBJECTS: Totally 20,764 patients with active electronic patient record until data gathering and with a history of at least four years without a specific alcohol use disorder after turning 18 years of age. METHODS: The Cox proportional hazard analysis with time-dependent covariates of potential accumulated risks over the previous four years. MAIN OUTCOME MEASURES: Time from inclusion until the first specific alcohol use disorder, defined by either an alcohol specific diagnostic code or a text fragment documenting an alcohol problem. RESULTS: In the unadjusted and adjusted Cox-regression with time-dependent covariates all variables were highly significant with adjusted hazard ratios ranging from 1.25 to 3.50. Addictive drugs, sick leaves, GGT, MCV and International Classification for Primary Care version 2 (ICPC-2), and International Classification of Diseases version 10 (ICD-10) diagnoses were analyzed. Elevated GGT and MCV, ICD-10-diagnoses, and gender demonstrated the highest hazard ratios. CONCLUSIONS: Many frequent health problems are potential predictors of an increased risk or vulnerability for alcohol use disorders. However, due to the modest hazard ratios, we were unable to establish a clinically useful tool. KEY POINTS Alcohol is potentially relevant for many health problems, but current strategies for identification and intervention in primary health care have not been successful. Many frequent clinical problems recorded in electronic patient records may indicate an increased risk for alcohol related health problems. The hazard ratios were modest and the resulting predictive model was unsatisfactory for diagnostic purposes. If we accepted a sensitivity as low as 0.50, the specificity slightly exceeded 0.75. With a low prevalent condition, it is obvious that the false positive problem will be vast. In addition to responding to elevated blood levels of liver enzymes, general practitioners should be aware of alcohol as a potentially relevant factor for patients with repeated events of many mental and psychosocial diagnoses and new sick leaves and repeated prescriptions of addictive drugs.

Insights into hydrate formation and stability of morphinanes from a combination of experimental and computational approaches.

Morphine, codeine, and ethylmorphine are important drug compounds whose free bases and hydrochloride salts form stable hydrates. These compounds were used to systematically investigate the influence of the type of functional groups, the role of water molecules, and the Cl(-) counterion on molecular aggregation and solid state properties. Five new crystal structures have been determined. Additionally, structure models for anhydrous ethylmorphine and morphine hydrochloride dihydrate, two phases existing only in a very limited humidity range, are proposed on the basis of computational dehydration modeling. These match the experimental powder X-ray diffraction patterns and the structural information derived from infrared spectroscopy. All 12 structurally characterized morphinane forms (including structures from the Cambridge Structural Database) crystallize in the orthorhombic space group P212121. Hydrate formation results in higher dimensional hydrogen bond networks. The salt structures of the different compounds exhibit only little structural variation. Anhydrous polymorphs were detected for all compounds except ethylmorphine (one anhydrate) and its hydrochloride salt (no anhydrate). Morphine HCl forms a trihydrate and dihydrate. Differential scanning and isothermal calorimetry were employed to estimate the heat of the hydrate ↔ anhydrate phase transformations, indicating an enthalpic stabilization of the respective hydrate of 5.7 to 25.6 kJ mol(-1) relative to the most stable anhydrate. These results are in qualitative agreement with static 0 K lattice energy calculations for all systems except morphine hydrochloride, showing the need for further improvements in quantitative thermodynamic prediction of hydrates having water···water interactions. Thus, the combination of a variety of experimental techniques, covering temperature- and moisture-dependent stability, and computational modeling allowed us to generate sufficient kinetic, thermodynamic and structural information to understand the principles of hydrate formation of the model compounds. This approach also led to the detection of several new crystal forms of the investigated morphinanes.

Discovery of novel series of 6-benzyl substituted 4-aminocarbonyl-1,4-diazepane-2,5-diones as human chymase inhibitors using structure-based drug design.

A novel series of 6-benzyl substituted 4-aminocarbonyl-1,4-diazepane-2,5-diones were explored as human chymase inhibitors using structure-based drug design according to the X-ray cocrystal structure of chymase and compound 1. The optimization focused on the prime site led to the attainment of compounds that showed potent inhibitory activity, and among them, 18R shows a novel interaction mode.

Synthesis, characterization, method development, and validation of nor-ethylmorphine hydrochloride reference material using established analytical techniques for dope control analysis.

Ethylmorphine is permitted internationally for therapeutic purposes where morphine is not indicated across the globe. Nor-ethylmorphine a major metabolite of ethylmorphine. To differentiate the intake of morphine from ethylmorphine, nor-ethylmorphine stable reference material is desirable. There is no available commercial source and no data for reference material context for this substance. Therefore, nor-ethylmorphine HCl was synthesized and characterized, and purity and potency were assessed using nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS), Fourier transform infrared spectroscopy (FT-IR), thermogravimetry (TGA), and high-performance liquid chromatography (HPLC). Purity and potency were found to be 98.29% and 96.40%, respectively, providing a fit for purpose reference material for doping control analysis in sports.

Synthesis, cytotoxic activities and cell cycle arrest profiles of naphtho[2,1-α]pyrrolo[3,4-c]carbazole-5,7(6H,12H)-dione glycosides.

Naphtho[2,1-α]pyrrolo[3,4-c]carbazole-5,7(6H,12H)-dione (NPCD) is known to be a very potent and selective cyclin D1-CDK4 inhibitors and could induce strong G1 phase arrest in breast tumor cell lines. In this work, the synthesis of five NPCD glycosides and their cytotoxic activities against eight tumor cell lines are presented, as well as the investigation of their cell cycle arrest profiles. The results showed that the introduction of a sugar moiety onto NPCD did not affect much of their cytotoxic activities, while the subtle structure of the sugar moiety affected the underlying mechanism strongly. In addition, NPCD showed distinct cell-cycle arrest profiles in BxPC3 prostate cells and MCF-7 breast cells, while NPCD glycosides shared similar cell cycle arrest profiles in MCF-7 and BxPC3 cells, which also indicated that not only the indolocarbazole framework as well known before but the sugar moiety can have a profound impact on the mechanism of action for these types of compounds.

Characterization of xenobiotic metabolizing enzymes in bovine small intestinal mucosa.

The intestinal mucosa plays a capital role in dictating the bioavailability of a large array of orally ingested drugs and toxicants. The activity and the expression of several xenobiotic metabolizing enzymes were measured in subcellular fractions from the duodenal mucosa of male veal calves and beef cattle displaying a functional rumen but differing in both age (about 8 months vs. 18 to 24 months) and dietary regimens (i.e., milk replacer plus hay and straw vs. corn and concentrated meal). Intestinal microsomes showed cytochrome P450 (CYP) 2B, 2C- and 3A-mediated activities and the presence of the corresponding immunorelated proteins, but no proof of CYP1A expression and/or functions could be provided. Intestinal microsomes were also active in performing reactions typically mediated by carboxylesterases (indophenylacetate hydrolysis), flavin-containing monooxygenases (methimazole S-oxidation), and uridindiphosphoglucuronyltransferases (1-naphthol glucuronidation), respectively. Cytosolic fractions displayed the glutathione S-transferase (GST)-dependent conjugation of 1-chloro-2,4-dinitrobenzene; besides, the GST-mediated conjugation of ethacrinic acid (GSTpi) or cumene hydroperoxide (GSTalpha) was matched by the presence of the corresponding immunorelated proteins. Conversely, despite the lack of measurable activity with 3,4-dichloronitrobenzene, a protein cross reacting with anti-rat GSTmu antibodies could be clearly detected. Although, as detected by densitometry, CYPs and GST isoenzymes tended to be more expressed in beef cattle than in veal calf preparations, there was a general poor correlation with the rate of the in vitro metabolism of the selected diagnostic probes.

Inhibitory effects of opioids on compound action potentials in frog sciatic nerves and their chemical structures.

An opioid tramadol more effectively inhibits compound action potentials (CAPs) than its metabolite mono-O-demethyl-tramadol (M1). To address further this issue, we examined the effects of opioids (morphine, codeine, ethylmorphine and dihydrocodeine) and cocaine on CAPs by applying the air-gap method to the frog sciatic nerve. All of the opioids at concentrations less than 10 mM reduced the peak amplitude of the CAP in a reversible and dose-dependent manner. The sequence of the CAP peak amplitude reductions was ethylmorphine>codeine>dihydrocodeine> or = morphine; the effective concentration for half-maximal inhibition (IC(50)) of ethylmorphine was 4.6 mM. All of the CAP inhibitions by opioids were resistant to a non-specific opioid-receptor antagonist naloxone. The CAP peak amplitude reductions produced by morphine, codeine and ethylmorphine were related to their chemical structures in such that this extent enhanced with an increase in the number of -CH(2) in a benzene ring, as seen in the inhibitory actions of tramadol and M1. Cocaine reduced CAP peak amplitudes with an IC(50) value of 0.80 mM. It is concluded that opioids reduce CAP peak amplitudes in a manner being independent of opioid-receptor activation and with an efficacy being much less than that of cocaine. It is suggested that the substituted groups of -OH bound to the benzene ring of morphine, codeine and ethylmorphine as well as of tramadol and M1, the structures of which are quite different from those of the opioids, may play an important role in producing nerve conduction block.

Driving under the influence of opiates: concentration relationships between morphine, codeine, 6-acetyl morphine, and ethyl morphine in blood.

Morphine and codeine are frequently identified in blood samples from impaired drivers. But whether these opiates reflect the use of prescription analgesics or abuse of the illicit drug heroin (diacetyl morphine) is not always obvious. Opiates, either alone or together with other drugs, were determined in 2,573 blood specimens from impaired drivers by sensitive and specific methods of analysis. The specific metabolite of heroin 6-acetyl morphine (6-AM) was quantifiable in only 52 cases (2%) at mean, median, and highest concentrations of 0.015, 0.010, and 0.10 mg/L, respectively. The mean, median, and highest concentrations of morphine were 0.046, 0.03, and 1.13 mg/L, respectively (N = 2,029). The corresponding concentrations of codeine (N = 1,391) were 0.047, 0.01, and 2.40 mg/L. Ethyl morphine was identified in 63 cases at a mean concentration of 0.055 mg/L (median 0.03 mg/L). When 6-AM was present in urine (N = 324), the mean morphine/codeine ratio in blood was 7.5 (median 6.7), and this important ratio was less than unity in only two cases. This study finds compelling evidence that approximately 90% of apprehended drivers in Sweden with morphine and codeine in their blood had used heroin.

[Study of cytotoxic and antiviral effects of some eye drops]. / Studiul proprietatilor citotoxice si antivirale ale unor colire.

The study of the cytotoxic and antiviral effect of six commercial mixtures, eye drops type, underlined the advantages of using eye drops with Indomethacin for Herpetic Keratitis, due to the antiviral effect and also for the lack of cytotoxicity.

Electrospray LC-MS method with solid-phase extraction for accurate determination of morphine-, codeine-, and ethylmorphine-glucuronides and 6-acetylmorphine in urine.

A method for the identification and quantification of morphine-3-glucuronide, codeine-6-glucuronide, ethylmorphine-6-glucuronide, and 6-acetylmorphine in human urine based on solid-phase extraction (SPE) and electrospray ionization liquid chromatography-mass spectrometry (LC-MS) was validated for use as a confirmation procedure in combination with immunochemical screening for opiates. Three deuterium-labelled analogues were used as internal standards: morphine-3-glucuronide-d3, codeine-d3, and 6-acetylmorphine-d3. Fifty-microliter aliquots of urine were prepared by SPE using 30-mg Oasis HLB cartridges. The chromatographic system consisted of a 2.0 x 100-mm C18 column and the gradient elution buffers used acetonitrile and 25 mmol/L formic acid. The protonated molecular ions were monitored in the selected ion monitoring mode together with one qualifier ion for each analyte. The interassay variability was less than 10% at the reporting limit 30 ng/mL for 6-acetylmorphine and 300 ng/mL for the other analytes. The method was validated by comparison with a reference gas chromatographic (GC)-MS method using authentic urine samples. The two methods agreed completely regarding identified analytes, and for the quantitative results there were slightly lower levels when measuring glucuronides directly as compared to total determination after hydrolysis by GC-MS. This result was to be expected because the free compounds are not measured with the LC-MS method. This study concludes that the presented LC-MS method is robust and reliable, and suitable for use as a confirmation method in clinical urine drug testing for opiates.

[Current problems in the quality control of pharmaceutical preparations manufactured in pharmacies II. Paracetamol contraining preparations]. / Magisztráilis gyógyszerkészítmények minoségellenorzésének aktuális kérdései II. Paracetamol tartalmú készítmények tartalmi meghatározáisi lehetoségei.

In our previous paper identification methods using chemical reactions and TLC are described for the active ingredients of pharmaceutical preparations in Formula Normales (FoNo VII.). Present paper introduces the development and validation of analytical methods suitable for quantitative determination of paracetamol containing dosage forms in FoNo VII. Titrimetric methods, UV spectroscopy and HPLC are used for assay of paracetamol and accompanying components (e.g. codeine, papaverine, caffeine and acetylsalicylic acid) in these preparations.

The effect of temperature on monoxygenase reactions in the microsomal membrane.

The effect of temperature on the rates of monoxygenase reactions was studied with microsomes prepared from phenobarbital pretreated rats. The rates of the N-demethylation of ethylmorphine, benzphethamine, aminopyrine, and p-nitroanisole were studied. Breaks at temperatures around 24 degrees C were observed in the Arrhenius plots of all these reactions. The energy of activation of these reactions has values of 10-12 and 19-21 kcal per mol at temperature ranges above and below the break temperature, respectively. The break, however, was not observed if 30% glycerol was added to the microsomes. The Arrhenius plot of the microsomal NADPH-cytochrome c reductase activity also did not show any break. The implications of these observations in relationship to the fluidity of the membrane, the translational mobility of membrane enzymes, and the rate of monoxygenase reactions are discussed.

Differential effects of neuroleptic agents on hepatic cytochrome P-450 isozymes in the male rat.

We report the effects of various dopamine receptor-blocking drugs on gene and protein expression, as well as the activity of several hepatic cytochrome P-450 (CYP) enzymes in the male Sprague-Dawley rat. At equipotent doses (with respect to receptor blockade and behavioural tests), the dopamine D2-receptor selective sulpiride and remoxipride gave a conspicuous down-regulation of CYP2C11 and its associated androstenedione 16 alpha-hydroxylation activity as well as of the CYP2C11-specific mRNA. The average immunoidentified CYP2C11 levels correlated with the CYP2C11-specific mRNA levels in all treatment groups (r = 0.994), indicating a transcriptional mechanism. The CYP3A protein was also selectively down-regulated. In contrast, androstenedione 5 alpha-reduction was significantly increased. Clozapine, a non-selective neuroleptic, gave the same effects on the steroid metabolism as sulpiride and remoxipride. In contrast, diverging effects were observed for clozapine, compared to sulpiride and remoxipride, on the immunoidentified CYP1A2, CYP2B1, and CYP3A. These proteins were elevated by clozapine, and down-regulated by sulpiride and remoxipride. Our results are of interest for the interpretation of preclinical dose ranging toxicity tests of neuroleptic agents in rats. They may also be relevant in relation to certain interactions and adverse reactions observed in the clinical use of these drugs. The down-regulation of certain CYP enzymes is most likely mediated by an interaction with the growth hormone secretion.

Inhibition of rat liver CYP2D in vitro and after 1-day and long-term exposure to neuroleptics in vivo-possible involvement of different mechanisms.

The aim of the present study was to investigate the influence of classic and atypical neuroleptics on the activity of rat CYP2D measured as a rate of ethylmorphine O-deethylation. The reaction was studied in control liver microsomes in the presence of neuroleptics, as well as in microsomes of rats treated intraperitoneally (i.p.) for 1-day or 2-weeks (twice a day) with pharmacological doses of the drugs (promazine, levomepromazine, thioridazine, perazine 10 mg kg(-1); chlorpromazine 3 mg kg(-1); haloperidol 0.3 mg kg(-1); risperidone 0.1 mg kg(-1); sertindole 0.05 mg kg(-1)), in the absence of the neuroleptics in vitro. Neuroleptics added in vitro to control liver microsomes decreased the activity of the rat CYP2D by competitive or mixed inhibition of the enzyme. Thioridazine (Ki=15 microM) was the most potent inhibitor of the rat CYP2D among the drugs studied, whose effect was more pronounced than that of the other neuroleptics tested: phenothiazines (Ki=18-23 microM), haloperidol (Ki=32 microM), sertindole (Ki=51 microM) or risperidone (Ki=165 microM). The investigated neuroleptics-when given to rats in vivo-also seemed to exert an inhibitory effect on CYP2D via other mechanisms. One-day exposure of rats to the classic neuroleptics decreased the activity of CYP2D in rat liver microsomes. After chronic treatment with the investigated neuroleptics, the decreased CYP2D activity produced by the phenothiazines was still maintained, while that caused by haloperidol diminished. Moreover, risperidone decreased the activity of that enzyme. The obtained results indicate drug- and time-dependent interactions between the investigated neuroleptics and the CYP2D subfamily of rat cytochrome P-450, which may proceed via different mechanisms: (1) competitive or mixed inhibition of CYP2D shown in vitro, the inhibitory effects of phenothiazines being stronger than those of haloperidol or atypical neuroleptics, but weaker than the effects of the respective drugs on human CYP2D6; (2) in vivo inhibition of CYP2D, produced by both 1-day and chronic treatment with phenothiazines, which suggests inactivation of enzyme by intermediate metabolites; (3) in vivo inhibition of CYP2D by risperidone, produced only by chronic treatment with the drug, which suggests its influence on the enzyme regulation.

Changes in adrenal microsomal cytochrome(s) P-450 with aging in the guinea pig.

Studies were carried out to investigate the mechanism(s) responsible for the changes in adrenal microsomal mixed function oxidase activity which occur with aging (30-200 days) in guinea pigs. With aging, the rate os metabolism of xenobiotics [ethylmorphine and benzo(a)pyrene] by adrenal microsomes increased 3- to 5-fold. Steroid 17 alpha- and 21-hydroxylations, when expressed per mg protein, were similar in immature (30 days old) and mature (200 days old) animals. Adrenal microsomal NADPH- and NADH-cytochrome c reductase activities and cytochrome b5 concentrations increased wih aging, but cytochrome P-450 concentrations were not significantly different in young and old guinea pigs. Maximal type I difference spectra produced by steroids were the same in adrenal microsomes from 30- and 200-day-old guinea pigs, but the ethylmorphine-induced spectrum was far greater in the older animals. Progesterone enhanced NADPH-cytochrome P-450 reductase activity to about the same extent in adrenal microsomes from 30- and 200-day-old guinea pigs. Ethylmorphine had no effect on the rate of reduction of cytochrome P-450 in adrenals from young animals but produced a 4-fold increase in activity in adrenals from older animals. The results demonstrate selective changes in adrenal xenobiotic metabolism with aging and suggest that changes in the composition and/or reactivity of adrenal cytochromes P-450 are responsible for the effects of aging.

Ethylmorphine O-deethylation cosegregates with the debrisoquin genetic metabolic polymorphism.

The single oral dose kinetics of ethylmorphine and its fractional metabolic clearance by O-dealkylation and N-dealkylation was investigated in five extensive and four poor metabolizers of dextromethorphan. In addition, the urinary metabolic ratios for these pathways (MRO and MRN, respectively) were investigated in a larger group of 27 extensive metabolizers and six poor metabolizers. The mean values for the fractional metabolic clearance by O-dealkylation and the MRO differed significantly between the poor metabolizers and extensive metabolizers without overlap between the values of either of these parameters in the two groups of subjects. In contrast, the corresponding parameters for the N-demethylation did not differ between poor metabolizers and extensive metabolizers. The area under the plasma concentration versus time curve was significantly higher (about three times higher) in the poor metabolizers compared with the extensive metabolizers (p = 0.004). Our data suggest that ethylmorphine is O-deethylated by the cytochrome P4502D6 isozyme inasmuch as both the fractional metabolic clearance by O-dealkylation and the MRO were found to cosegregate with the phenotype for the O-demethylation of dextromethorphan in our group of subjects.

Restoration of hydroperoxide-dependent lipid peroxidation by 3-methylcholanthrene induction of cytochrome P-448 in hepatoma microsomes.

Microsomal membranes from the slow-growing Morris hepatoma 9618A catalyze, in the presence of t-butyl hydroperoxide, lower rates of lipid peroxidation than rat liver microsomes. The cytochrome P-450 content of hepatoma microsomes is about 40% that of the liver. SKF 525-A, an inhibitor of mixed-function oxidase, produces in hepatoma microsomes a P-450 type I binding spectrum similar to that of hepatic microsomes. The concentration of the inhibitor required for half-maximal spectral change is about 2 microM in both microsome types. SKF 525-A or ethylmorphine inhibit lipid peroxidation of normal and tumor microsomes to the same extent (about 60%). Treatment of the tumor-bearing rats with 3-methylcholanthrene increases the hepatoma cytochrome P-450 to values comparable to those of control membranes, although the hemoprotein has a peak in the CO-reduced difference absorption spectrum at 448 nm. The cytochrome P-448 induction is accompanied by an almost complete restoration of the hydroperoxide-dependent lipid peroxidation.