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1.
Int J Legal Med ; 136(4): 1037-1049, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35013768

RESUMO

Further to a previous publication by the European Council of Legal Medicine (ECLM) concerning on-site forensic and medico-legal scene and corpse investigation, this publication provides guidance for forensic medical specialists, pathologists and, where present, coroners' activity at a scene of death inspection and to harmonize the procedures for a correct search, detection, collection, sampling and storage of all elements which may be useful as evidence, and ensure documentation of all these steps. This ECLM's inspection form provides a checklist to be used on-site for the investigation of a corpse present at a crime or suspicious death scene. It permits the collection of all relevant data not only for the pathologist, but also for forensic anthropologists, odontologists, geneticists, entomologists and toxicologists, thus supporting a collaborative work approach. Detailed instructions for the completion of forms are provided.


Assuntos
Entomologia , Medicina Legal , Antropologia , Cadáver , Medicina Legal/métodos , Patologia Legal , Humanos
2.
Traffic Inj Prev ; 19(8): 786-793, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30024768

RESUMO

OBJECTIVE: The objective of this study was to present the prevalence and concentrations of drugs in blood samples of drivers involved in road traffic accidents (RTAs) and to discuss the effects of adopting different concentration cutoff values proposed or applied in other European countries on the number of driving under the influence of drugs (DUID) offenses. METHODS: Blood samples from drivers involved in RTAs in Padova province from 2014 to 2017 were analyzed for the presence of alcohol and drugs. The prevalence of positive subjects was reported for each substance adopting the limits of quantification (LOQs) of our laboratory and the concentration cutoff values proposed and/or used in other European countries. The reduction of cases of driving under the influence of illicit drugs in applying different cutoffs was calculated. RESULTS: Four thousand four hundred forty-three blood samples were analyzed: 23.7% were positive for alcohol and 19.9% for psychoactive drugs, with prevalences of polydrug and alcohol-drug abuse of 4.5 and 6%, respectively. The most frequently detected drugs were cannabinoids (9.7%) and cocaine (7.2%), followed by benzodiazepines (4.1%), opiates (1.9%), and other opioids (1.7%). Barbiturates, amphetamines, and ketamine were identified in a much smaller number of cases. The overall decrease in DUID cases when adopting different cutoffs with respect to cases above the LOQs was between 8 and 84%. The adoption of high LOQs such as those used in the European Union's research project on Driving Under the Influence of Drugs, Alcohol and Medicines (DRUID) decreases the hypothetical number of DUID offenses by a quarter, and per se limits proposed as broadly equivalent to a blood alcohol concentration (BAC) between 0.2 and 0.8 g/L dramatically reduce the cases of DUID (cocaine -81%, cannabis -79%, opioids -97%, opiates -96%, and amphetamines -77%); no ketamine-positive samples were above the cutoff. CONCLUSIONS: The implementation of high analytical limits or per se limits based on impairing concentrations in the Italian legislation could result in the prosecution of a much lower number of drugged drivers involved in RTAs, with a decrease from 25% to more than 80% depending on the limits.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Dirigir sob a Influência/estatística & dados numéricos , Preparações Farmacêuticas/sangue , Adolescente , Adulto , Idoso , Humanos , Itália , Pessoa de Meia-Idade , Adulto Jovem
3.
Forensic Sci Int ; 265: 193-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27017567

RESUMO

Ketamine (KT) is used to induce and maintain general anaesthesia in combination with sedative drugs in human and animals. Because of its dissociative and hallucinogenic effects, KT has become a recreational drug in a variety of social settings and may be included in the panel of drugs of abuse that are controlled in driving under the influence (DUI) ascertainment. In a local driving license re-granting protocol, a case where a veterinary physician was found positive to KT and nor-ketamine (NK) in hair suggested the possibility of a professional exposure in a veterinary setting and prompted an experimental study. Male (7) and female (4) veterinary physicians were recruited on a voluntary base. Detailed information was collected on their habits, use of drugs, professional practice, frequency and mode of using KT injections. Hands and skin were examined. Head hair and pubic hair were collected. Two naïve subjects, starting their professional practice at a local veterinary clinic, were recruited and their hair (head, pubic, axillary, thoracic hair, and beard) and urine were collected before and after usual clinic activity. Hair were cut according to their length, washed, pulverized and 25mg were extracted and analyzed by liquid chromatography coupled to high accuracy, high resolution mass spectrometry. All the hair samples from the veterinary physicians turned to be positive for KT, at a concentration varying from 0.010 to 0.840ng/mg in head hair and from 0.040 to 2.04ng/mg in pubic hair; NK ranged from not detected to 0.080ng/mg in head hair, from not detected to 0.100 in pubic hair; when KT was ≥0.100, NK was always detected. For the two naïve subjects, hair from different body sites were negative before they started their activity, and positive one month later; some urine samples resulted positive and confirmed systemic exposure to KT. The possibility of unaware exposure to KT was demonstrated. The site of absorption is skin, independently from the presence of skin injuries due to hand contact with KT injection solutions and/or animal body fluids by veterinary physicians during clinical activities and animal handling. Possible adverse systemic effects by unaware KT exposure need to be studied and concerns have arisen as to healthy and safe workplace policies. Comparison with a population of subjects undergoing driving license re-granting evidenced a larger range of concentration in this latter setting (0.050-10.0ng/mg for KT, not detected to 0.100ng/mg for NK).


Assuntos
Anestésicos Dissociativos/sangue , Cabelo/química , Ketamina/sangue , Exposição Ocupacional , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Medicina Veterinária , Adulto Jovem
4.
Clin Pharmacol Ther ; 100(3): 268-74, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27007551

RESUMO

The aim of this study was to evaluate the in vitro steroid sensitivity as a predictor of clinical response to glucocorticoids in childhood idiopathic nephrotic syndrome (INS). Seventy-four patients (median age 4.33, interquartile range [IQR] 2.82-7.23; 63.5% male) were enrolled in a prospective multicenter study: in vitro steroid inhibition of patients' peripheral blood mononuclear cell proliferation was evaluated by [methyl-(3) H] thymidine incorporation assay at disease onset (T0) and after 4 weeks (T4) of treatment. Steroid dependence was associated with increased in vitro sensitivity at T4 assessed both as drug concentration inducing 50% of inhibition (IC50 ; odds ratio [OR] = 0.48, 95% confidence interval [CI] = 0.24-0.85; P = 0.0094) and maximum inhibition at the highest drug concentration (Imax ; OR = 1.13, 95% CI = 1.02-1.31; P = 0.017). IC50 > 4.4 nM and Imax < 92% at T4 were good predictors for optimal clinical response. These results suggest that this test may be useful for predicting the response to glucocorticoid therapy in pediatric INS.


Assuntos
Imunossupressores/administração & dosagem , Imunossupressores/farmacologia , Leucócitos Mononucleares/efeitos dos fármacos , Metilprednisolona/administração & dosagem , Metilprednisolona/farmacologia , Síndrome Nefrótica/tratamento farmacológico , Relação Dose-Resposta a Droga , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Metilprednisolona/uso terapêutico , Estudos Prospectivos , Recidiva , Fatores de Tempo
5.
Horm Metab Res ; 34(5): 260-4, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12063640

RESUMO

The IgG glycation level of 30 healthy subjects and 60 type 2 diabetic patients with different degrees of metabolic control was evaluated by matrix-assisted laser desorption ionization mass spectrometry, a technique allowing the determination of mass increase of the IgG molecule. When applied to the digested mixture obtained by the action of papain on the plasma protein fraction, the same method established the mass increase of Fab and Fc fragments of IgG; for the former, a higher mass increase was found, possibly explained by its high reactivity to glucose. Experimental results were confirmed by molecular modeling calculations. Results suggest that the immunodeficiency observed in diabetic patients may be due to the inhibition of molecular recognition between antibody and antigen as a result of a change in functionality of the modified Fab fragment of IgG.


Assuntos
Imunoglobulina G/metabolismo , Lisina/análogos & derivados , Idoso , Glicemia/metabolismo , Proteínas Sanguíneas/metabolismo , Cromatografia Líquida de Alta Pressão , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Glucose/metabolismo , Hemoglobinas Glicadas/metabolismo , Glicoproteínas/metabolismo , Humanos , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/metabolismo , Imunoglobulina G/química , Lisina/sangue , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Proteínas/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
6.
Rapid Commun Mass Spectrom ; 15(13): 1061-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11404842

RESUMO

The enzymatic reaction between DOPA and tyrosinase, the enzyme considered to be responsible for melanogenesis, was carried out in the presence of polyethylene glycol (PEG). This choice was made in order to increase the solubility of melanins, since these polymers are highly insoluble. The reaction mixtures were sampled at different times, immediately ultrafiltered to remove the enzyme, lyophilized, and analyzed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The results were very different from those obtained in the absence of PEG. Only a few oligomers of dihydroxyindole (DHI) and dihydroxyindole-2-carboxylic acid (DHICA) were detected in low abundances, whereas new species originating from reaction of PEG with species belonging to the Raper-Mason pattern appeared. The results show that, in the presence of PEG, tyrosinase-catalyzed oligomerization of DOPA exhibits kinetics slower than those observed in the absence of the polymer. However, melanogenesis still takes place in the presence of PEG, as indicated by the formation of black pigments and by the detection of DHI and DHICA oligomers, considered to be the first intermediates in melanin formation.


Assuntos
Di-Hidroxifenilalanina/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Polietilenoglicóis/farmacologia , Agaricales/enzimologia , Di-Hidroxifenilalanina/química , Indóis/análise , Indóis/química , Cinética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
7.
Rapid Commun Mass Spectrom ; 15(12): 1000-10, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11400210

RESUMO

A set of aminoalkoxy-substituted, differently annullated furocoumarins, differing in the position of the aminoalkoxy chain and in the unsaturation level of the fused ring, has been subjected to electron impact and electrospray ionisation (ESI) experiments. In order to achieve a distinct characterisation of isomeric compounds, which partially failed under electron impact conditions, collision-induced dissociation experiments were performed on protonated molecules. The breakdown curves obtained by varying the tickle voltage on an ion trap ESI instrument led to the desired characterisation.


Assuntos
Furocumarinas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Benzeno/química , Furocumarinas/química , Isomerismo
8.
J Mass Spectrom ; 36(4): 370-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11333439

RESUMO

Structural information on 'AGE-peptides,' a class of substances belonging to advanced glycation end products (AGE) and originating by proteolysis of glycated proteins, was gained through various analytical approaches on the mixture produced by proteinase K digestion of in vitro glycated bovine serum albumin. Both matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and high-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS) were employed, and the results were compared with those from conventional spectroscopic methods (UV, fluorescence, gel permeation). The data acquired by the various techniques all depict the digestion mixtures as highly complex, with components exhibiting molecular mass in the range 300-3500 Da. In the analysis of HPLC/ESI-MS data, identification of AGE-peptides was facilitated by 3D mapping. Structural information was gained by means of multiple mass spectrometric experiments.


Assuntos
Produtos Finais de Glicação Avançada/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Espectrometria de Massa de Íon Secundário/métodos , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Técnicas In Vitro , Reprodutibilidade dos Testes , Soroalbumina Bovina/química , Espectrometria de Fluorescência/métodos , Espectrofotometria Ultravioleta/métodos
9.
Rapid Commun Mass Spectrom ; 15(5): 364-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11241768

RESUMO

A semiquantitative determination of two bis-indole antitumor alkaloids, vincristine and vinblastine, has been performed by flow-injection electrospray ionization mass spectrometric analysis of the extracts of Catharanthus roseus. Leaves and flowers of two different phenotypes (pink flower and white flower) obtained from somatic embryogenesis were thus examined and compared with the field-grown mother plant. Different amounts of vincristine and vinblastine were detected depending on the examined samples.


Assuntos
Antineoplásicos Fitogênicos/análise , Plantas Medicinais/química , Vimblastina/análise , Vincristina/análise , Antineoplásicos Fitogênicos/biossíntese , Calibragem , Análise de Injeção de Fluxo , Folhas de Planta/química , Folhas de Planta/metabolismo , Plantas Medicinais/embriologia , Plantas Medicinais/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Vimblastina/biossíntese , Vincristina/biossíntese
10.
Rapid Commun Mass Spectrom ; 14(19): 1862-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11006597

RESUMO

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry experiments were applied to study the influence of ultraviolet (UV) irradiation in melanogenesis. Samples were prepared starting from three different precursors, tyrosine, Dopa and dopamine, in the presence or absence of tyrosinase, the enzyme responsible for the synthesis of melanin. Enzymatic reactions were carried out for 10, 30, 60 and 120 min under UV irradiation at 365 nm, and aliquots were then immediately ultrafiltered and lyophilized. Samples obtained by irradiation of tyrosine solution revealed the formation of 5,6-dihydroxyindole (DHI) oligomers up to pentamers at 120 min; the reaction kinetics were markedly enhanced in the presence of tyrosinase. In the case of Dopa, UV irradiation favored melanogenesis only in the presence of the enzyme; in this case, many reaction pathways were activated, originating various oligomeric species of Dopa, DHI and 5,6-dihydroxyindole-2-carboxylic acid (DHICA). Conversely, when dopamine was used as tyrosinase substrate under UV light, mechanisms of melanogenesis different from those generated by simple enzymatic reaction without irradiation were not activated, as the same oligomeric species were present.


Assuntos
Di-Hidroxifenilalanina/química , Di-Hidroxifenilalanina/efeitos da radiação , Dopamina/química , Dopamina/efeitos da radiação , Melaninas/química , Melaninas/efeitos da radiação , Tirosina/química , Tirosina/efeitos da radiação , Monofenol Mono-Oxigenase/química , Fotoquímica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Raios Ultravioleta
11.
Rapid Commun Mass Spectrom ; 14(16): 1499-506, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10931545

RESUMO

The mass spectrometric behaviour of some two-coordinated linear gold(I) complexes has been studied by fast atom bombardment (FAB) and laser desorption/ionisation (LDI) methods. The results obtained demonstrate some interesting aspects of Au-Au interactions. The detection under FAB conditions of Au(n)(+) clusters, in particular of Au(3)(+) species, can be rationalised by the presence of significant intramolecular Au-Au interactions, while the formation under LDI conditions of Au(n)(+) clusters can be considered indicative of Au(ellipsis)Au intermolecular interactions present in the solid state. Copyright 2000 John Wiley & Sons, Ltd.

12.
J Am Soc Mass Spectrom ; 11(2): 153-9, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10689668

RESUMO

The glycation-induced functional change of immunoglobulins is of particular interest. The glycation levels of IgG in 10 healthy subjects and 20 diabetic patients with different degrees of metabolic control were studied by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. It reveals the number of glucose molecules that have condensed on the protein, which range from 1 to 5 for healthy subjects, from 5 to 9 for well controlled diabetic patients, and from 10 to 25 for poorly controlled ones. The identification of the most favored glycation sites has been obtained by MALDI analysis of standard and in vitro glycated IgG and plasma protein fraction of a healthy subject after digestion with papain, releasing Fab and Fc fragments of the molecule. Both experiments, as well as molecular modeling of the whole protein, confirm that the most of glucose molecules have condensed on the Fab fragment of IgG, suggesting that the immune deficiency observed in diabetic patients may be explained at the molecular level by a more effective glycation of the Fab fragment, thus inhibiting the process of molecular recognition between antibody and antigen.


Assuntos
Glucose/química , Imunoglobulina G/química , Idoso , Glicemia/metabolismo , Proteínas Sanguíneas/química , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Hidrólise , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/química , Modelos Moleculares , Peso Molecular , Papaína , Conformação Proteica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
J Mass Spectrom ; 34(12): 1354-60, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10587632

RESUMO

Ten long-chain saturated and unsaturated alcohols were reacted with the ionic species [C(2) H(2) N](+) and [C(3) H(4) N](+) generated by ionization of acetonitrile into an ion trap. The mass spectra of the compounds under investigation show the formation of [M -H](+), [M + C(2) H(2) N](+) and [M + C(2) H(4) N](+) ions in the case of saturated alcohols, whereas for monounsaturated and polyunsaturated derivatives additional peaks corresponding to [M + H](+) and [M + H -H(2) O](+) are observed. The reaction mechanisms were investigated by means of D- and (13)C-labelled acetonitrile. Collisional experiments were performed on the [M + C(3) H(4) N](+) species from the polyunsaturated alcohols in order to identify any possibly diagnostic fragments for the identification of the double bond positions. Copyright 1999 John Wiley & Sons, Ltd.

14.
J Mass Spectrom ; 34(9): 922-9, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10491588

RESUMO

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry was used to study melanogenesis starting from Dopa and dopamine, the latter considered one of the precursors of neuromelanins. These substrates were left to react with the peroxidase - H(2)O(2) system, which is postulated to play an important role in melanin biosynthesis. Samples were prepared by ultrafiltering the substrate - enzyme solution after 30, 60, 120, 240 and 360 min of reaction and aliquots were immediately lyophilized. The reaction of dopamine with peroxidase - H(2)O(2) favoured the formation of dopamine oligomers up to octamers. In contrast, the action of either peroxidase or H(2)O(2) alone, studied for comparison, did not lead to melanin production and only dimeric and trimeric species were observed. Also for Dopa, analogous results were obtained in the presence of either peroxidase or H(2)O(2) alone, without melanin formation. Conversely, Dopa with the peroxidase - H(2)O(2) system led to the formation of a black precipitate after 120 min of reaction, and oligomers of 5,6-dihydroxyindole (DHI), an intermediate of melanogenesis, were detected, together with products of further oxidation. Faster kinetics were observed when Dopa was treated with tyrosinase, the enzyme catalysing the oligomerization of tyrosine to melanins, leading to the formation mainly of DHI oligomers.


Assuntos
Di-Hidroxifenilalanina/metabolismo , Dopamina/metabolismo , Melaninas/química , Melaninas/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Di-Hidroxifenilalanina/química , Dopamina/química , Peroxidase do Rábano Silvestre/metabolismo , Monofenol Mono-Oxigenase/metabolismo
15.
Carcinogenesis ; 20(3): 431-5, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10190558

RESUMO

The aim of this study was to compare (+/-)-r-7,t-8-dihydroxy-t-9,10-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene (anti-BPDE)-DNA adduct levels in groups of humans subjected to various levels of polycyclic aromatic hydrocarbon (PAH) (benzo[a]pyrene) exposure. An HPLC/fluorescence method was applied to detect specifically anti-BPDE-DNA adducts in mononuclear white blood cells [lymphocyte plus monocyte fraction (LMF)] from humans exposed to PAHs. A total of 130 subjects comprised the sample population: 26 psoriatic patients (3 days after clinical coal tar treatment of the skin), 15 coke oven workers, 19 chimney sweeps, 36 aluminium anode plant workers and 34 non-occupationally PAH-exposed subjects (controls). PAH exposure was assessed in each group by means of the urinary excretion of 1-pyrenol (mean group levels: 1.2, 0.7, 0.3, 65.0 and 0.1 micromol/mol creatinine in coke oven workers, chimney sweeps, aluminium plant anode workers, psoriatic patients and non-occupationally PAH-exposed subjects, respectively). HPLC/fluorescence analysis of BPDE-DNA adducts showed that the percentage of subjects with adduct levels exceeding the 95 percentile control subject value (8.9 adducts/10(8) nucleotides) was significantly high in coke oven workers (46.7%) and chimney sweeps (21.0%) (chi2 test, P < 0.01 and P < 0.05, respectively) but not in aluminium plant workers (11.1%) and psoriatic patients (0%). The increase in BPDE-DNA adduct levels in LMF (Ln values) was significantly related to chronic inhalatory and high PAH exposure (linear multiple regression analysis, F = 6.37, P < 0.01; t = 4.2, P < 0.001). Skin acute (or short-term) and high PAH exposure, charcoal-grilled meat consumption and smoking habit did not seem to influence BPDE-DNA adduct formation in LMF.


Assuntos
7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/análise , Cromatografia Líquida de Alta Pressão/métodos , Adutos de DNA/análise , Leucócitos Mononucleares/química , Compostos Policíclicos/toxicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Pirenos/análise , Espectrometria de Fluorescência , Urina/química
16.
Adv Exp Med Biol ; 467: 779-87, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10721131

RESUMO

The role of tyrosinase and peroxidase in melanogenesis of 5-hydroxytryptamine, 5,6- and 5,7-dihydroxytryptamines was investigated by matrix-assisted laser desorption/ionization mass spectrometry. Each enzyme was incubated with the tryptamine derivatives and samples were drawn at various times, ultrafiltered and immediately lyophilized. The results indicated that peroxidase promotes oligomerization of 5-HT with fast kinetics but with yields lower than those achieved by tyrosinase. 5,6- and 5,7-DHT formed low molecular mass oligomers in the presence of peroxidase alone. The addition of hydrogen peroxide evidences different reactivity of the two isomers: 5,6-DHT formed immediately a black precipitate while oligomers of the molecule itself and of its oxidation products were detectable for 5,7-DHT.


Assuntos
5,6-Di-Hidroxitriptamina/química , 5,7-Di-Hidroxitriptamina/química , Melaninas/química , Serotonina/química , Peroxidase do Rábano Silvestre , Peróxido de Hidrogênio , Indicadores e Reagentes , Monofenol Mono-Oxigenase , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
17.
Rapid Commun Mass Spectrom ; 12(12): 779-82, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9650303

RESUMO

The potential of ion trap mass spectrometry has been evaluated for the characterization and distinction of two isomeric amphetamines drugs, namely N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine and N-ethyl-3,4-methylenedioxyamphetamine. Whereas the electron impact spectra of the two molecules lack specificity, collisional experiments on the ionic species at m/z 72 allows unequivocal distinction between the two isomers. Analogous results are achieved by positive ion chemical ionization and collisional experiments on the protonated molecules. All the different approaches have been successfully applied to the gas chromatography/mass spectrometry analysis of a tablet of illicit drug.


Assuntos
3,4-Metilenodioxianfetamina/análogos & derivados , Drogas Desenhadas/análise , Drogas Ilícitas/análise , 3,4-Metilenodioxianfetamina/análise , Cromatografia Gasosa-Espectrometria de Massas
19.
Rapid Commun Mass Spectrom ; 11(6): 673-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9149436

RESUMO

Studies that have been performed by MALDI mass spectrometry in the field of non-enzymatic protein glyco-oxidation are briefly reviewed. The results obtained by in vitro and in vivo experiments demonstrate the power of this technique, which is able to give information on the number of sugar molecules condensed on specific proteins and, consequently, represents a new and specific diagnostic tool in diabetes control.


Assuntos
Glucose/química , Proteínas/química , Oxirredução , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
20.
Rapid Commun Mass Spectrom ; 11(7): 774-80, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9161046

RESUMO

The electron-impact (EI) mass spectrometric behaviour of a series of 8-aza-purines derivatized with hydroxymethylcyclopentane and exhibiting cis-trans isomerization in the cyclopentane ring has been studied in detail with the aid of metastable-ion data. Specific fragmentation processes, present in both EI and mass analysed ion kinetic energy spectra of molecular species, allow characterization of the different pairs of stereoisomers. Contrary to what is observed in the case of purine analogs, the presence of a nitrogen atom in position 8 strongly inhibits fragmentation processes related to the heterocycle.


Assuntos
Fármacos Anti-HIV/química , Fármacos Anti-HIV/síntese química , Nucleosídeos/química , Nucleosídeos/síntese química , Compostos Aza/síntese química , Compostos Aza/química , Cromatografia Gasosa-Espectrometria de Massas , Nitrogênio/química , Estereoisomerismo
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