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1.
J Forensic Sci ; 67(4): 1461-1467, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35521892

RESUMO

A commercial high-resolution X-ray computed tomography (CT) was utilized for non-destructive analysis of single fibers. The micro-CT apparatus was employed because it is applicable to both colored and colorless fibers. A sample preparation using adhesive sheets was demonstrated, and the method is similar to typical tape-lift sample collection method in crime cases. Different cross-sectional shapes of nylon and polyester single fibers were non-destructively distinguished, and the method is applicable to all types of fibers. Cross-sectional areas, aperture ratios, and volumes of individual fibers were directly and automatically measured using the open-source software. The observed parameters were within a coefficient of variation of 3%. In addition, a mass of a single fragment of a fiber can be estimated when the local density is given.


Assuntos
Adesivos , Tomografia Computadorizada por Raios X , Software , Tomografia Computadorizada por Raios X/métodos
2.
Asia Pac J Clin Oncol ; 13(2): e132-e137, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26245851

RESUMO

AIM: Cetuximab improves the prognosis for wild-type KRAS metastatic colorectal cancer (MCRC). We evaluated the safety and efficacy of cetuximab in combination with irinotecan in Japanese patients with wild-type KRAS MCRC refractory to irinotecan, oxaliplatin and fluoropyrimidines. METHODS: Cetuximab was administered initially at a dose of 400 mg/m2 , followed by weekly infusions at 250 mg/m2 . Irinotecan was administered every 2 weeks at 150 mg/m2 . Primary endpoint was the incidence of grade 3/4 adverse events; secondary endpoints included overall survival (OS), progression-free survival (PFS), response rate (RR), time to treatment failure (TTF), and TTF for irinotecan. RESULTS: Thirty-four patients were enrolled. Grade 3 or 4 toxicities were leucopenia (11.8%), neutropenia (23.5%), anemia (11.8%), fatigue (2.9%), anorexia (2.9%), diarrhea (14.7%) and hypomagnesemia (5.9%). Skin toxicities were as follows (any grade/grade 3): acne (94.2/8.8%), rash (55.9/0%), nail changes (75.5/8.8%) and hand-foot syndrome (55.9/5.9%). Median PFS was 6.0 months (95%CI; 4.7-7.4). Median OS was 12.9 months (95%CI; 10.0-15.9). RR was 26.4%. Median TTF was 5.1 months and median TTF for irinotecan was 5.0 months (95%CI; 4.3-5.6). CONCLUSION: Cetuximab with irinotecan therapy was well tolerated in Japanese patients with wild-type KRAS colorectal cancer refractory to irinotecan, oxaliplatin and fluoropyrimidine, thus demonstrating the feasibility of their usage.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Cetuximab/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Proteínas ras/efeitos dos fármacos , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Povo Asiático , Camptotecina/administração & dosagem , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Cetuximab/administração & dosagem , Cetuximab/farmacologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida , Resultado do Tratamento
3.
Int J Legal Med ; 131(1): 143-152, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27544358

RESUMO

Recently, various synthetic cannabinoid (SC) compounds that have been slightly modified at the functional groups have been identified in Japan. However, the structural elucidation of these new compounds using conventional approaches such as gas chromatography-electron impact-mass spectrometry (GC-EI-MS) is difficult. As such, indole and indazole SCs were scanned using GC-MS-EI, positive GC-chemical ionization (CI)-MS, and negative GC-chemical ionization-MS, allowing for efficient structural elucidation of unknown SC compounds. Pure substances have been employed for the study.


Assuntos
Canabinoides/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Drogas Desenhadas , Indazóis/química , Indóis/química
4.
J Med Ultrason (2001) ; 43(2): 271-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27033871

RESUMO

Immunoglobulin G4-related disease (IgG4-RD) represents a group of disorders that share features of inflammation, plasma cell infiltrates, and fibrosis. Sclerosing cholangitis is a disorder involving inflammation, scarring, and destruction of the bile ducts. IgG4-related sclerosing cholangitis (IgG4-SC) has been proposed as a bile duct lesion associated with IgG4-RD. This disease entity can be distinguished from other types of sclerosing cholangitis and classified into four types based upon the region of strictures revealed by cholangiography. Here, we present two cases in which the finding of bile duct wall thickening visualized with transabdominal ultrasonography was useful in the diagnosis of patients with IgG4-SC. At present, transabdominal ultrasonography is not included in the diagnostic algorithm for IgG4-SC. We are certain that detailed observation of the bile duct wall with transabdominal ultrasonography can make a significant contribution to the diagnosis of IgG4-SC. Furthermore, we propose that transabdominal ultrasonography may be useful in following clinical improvement in cases where a steroid trial is the best option for treatment. Both cases emphasize the practicality of transabdominal ultrasonography in the diagnosis and follow-up observation of IgG4-SC.


Assuntos
Ductos Biliares/diagnóstico por imagem , Colangite Esclerosante/diagnóstico por imagem , Colangite Esclerosante/imunologia , Imunoglobulina G/sangue , Ultrassonografia/métodos , Idoso , Colangite Esclerosante/tratamento farmacológico , Colangite Esclerosante/patologia , Diagnóstico Diferencial , Seguimentos , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Imageamento por Ressonância Magnética , Masculino , Resultado do Tratamento
5.
J Med Ultrason (2001) ; 43(3): 381-6, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26920145

RESUMO

PURPOSE: The purpose of this study was to examine the effects of using an ultrasound phantom (ECHOZY) and a volume navigation system (Vnavi) in abdominal ultrasonography training for young residents. METHODS: Nine third-year residents underwent abdominal ultrasonography training: controls, comprising five residents; and the ECHOZY + Vnavi group, comprising four residents. Residents were trained in abdominal ultrasound examinations using both educational videos and hands-on clinical training. The ECHOZY + Vnavi group also received training using an ultrasound phantom and volume navigation system. The time needed for abdominal ultrasound examination was calculated at 4 months (early), 8 months (middle), and 12 months (late) after starting training. The ability of each resident to visualize 20 abdominal structures on normal patients was also evaluated retrospectively. RESULTS: In the early period, the ECHOZY + Vnavi group needed significantly longer to complete examinations than controls (545 ± 125 s versus 392 ± 81 s, p < 0.01), but showed significantly better ability scores (17.5 ± 0.6 versus 13.4 ± 1.1, p < 0.05). Both these differences disappeared by the middle period (338 ± 107 s versus 259 ± 130 s and 17.8 ± 0.5 versus 16.0 ± 0.7). CONCLUSION: In spite of longer examination times, training residents in abdominal ultrasonography using an ultrasound phantom and volume navigation system may be useful in the early period.


Assuntos
Abdome/diagnóstico por imagem , Internato e Residência , Modelos Anatômicos , Imagens de Fantasmas , Ultrassonografia , Humanos , Aprendizagem , Estudos Retrospectivos , Fatores de Tempo , Ultrassonografia/instrumentação , Ultrassonografia/métodos , Gravação em Vídeo
6.
Forensic Toxicol ; 33(2): 175-194, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26257831

RESUMO

A number of N-alkyl indole or indazole-3-carbonyl analogs, with modified chemical structures, are distributed throughout the world as synthetic cannabinoids. Like synthetic cannabinoids, cathinone analogs are also abused and cause serious problems worldwide. Acute deaths caused by overdoses of these drugs have been reported. Various analytical methods that can cope with the rapid changes in chemical structures are required for routine analysis and screening of these drugs in seized and biological materials for forensic and clinical purposes. Although many chromatographic methods to analyze each drug have been published, there are only a few articles summarizing these analytical methods. This review presents the various colorimetric detections, immunochemical assays, gas chromatographic-mass spectrometric methods, and liquid chromatographic-mass spectrometric methods proposed for the analysis of synthetic cannabinoids and cathinones.

7.
Anal Sci ; 27(10): 999-1005, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21985924

RESUMO

A rapid, specific, and sensitive method for the simultaneous quantitation of organophosphates (fenitrothion (MEP), malathion, and phenthoate (PAP)), glufosinate (GLUF), and glyphosate (GLYP) in human serum and urine by gas chromatography-mass spectrometry (GC-MS) has been validated. All of the targeted compounds together with the internal standard were extracted from the serum and urine using a mix-mode TiO-C(18) monolithic spin column. The recovery of organophosphates from serum and urine ranged from 12.7 to 49.5%. The recovery of GLUF and GLYP from serum and urine ranged from 1.9 to 7.9%. The intra- and inter-accuracy and precision (expressed as relative standard deviation, %RSD) were within 96.7-107.7% and 4.0-13.8%, respectively. The detection and quantitation limits for serum and urine were 0.1 and 0.1 µg/ml, respectively, for organophosphates, 0.1 and 0.5 µg/ml, respectively for GLUF and GLYP. The method had linear calibration curves ranging from 0.1 to 25.0 µg/ml for organophosphates and 0.5-100.0 µg/ml for GLUF, and GLYP. The validated method was successfully applied to a clinical GLYP poisoning case.


Assuntos
Aminobutiratos/sangue , Aminobutiratos/urina , Glicina/análogos & derivados , Compostos Organofosforados/sangue , Compostos Organofosforados/urina , Cromatografia Gasosa-Espectrometria de Massas , Glicina/sangue , Glicina/urina , Humanos , Ácidos Polimetacrílicos/química , Sensibilidade e Especificidade , Titânio/química , Glifosato
8.
J AOAC Int ; 94(3): 765-74, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21797004

RESUMO

A monolithic spin column was developed for the extraction of analytes from biological materials. This column was constructed by packing a monolithic silica disk into a spin column. Sample loading, washing, and elution of the target drugs were accomplished simply by centrifugation of the column. Opiates and benzodiazepines are abused throughout the world. Identification and quantification of these drugs is very important to solve crimes or the cause of death. Three opiates (morphine, codeine, and dihydrocodeine) were extracted from urine and serum by using the column. After conversion to trimethylsilyl derivatives of the opiates by vigorous mixing with the derivatizing reagent, the solution was subjected to GC/MS. A linear curve was observed for opiates from 10 to 2500 ng/mL in urine and 5 to 1200 ng/mL in serum, respectively (correlation coefficient > 0.996). For benzodiazepines, the hydroxyl metabolites of triazolam and etizolam were extracted from urine using the column, and the eluate was directly analyzed by HPLC/MS without evaporation. The LOD values were at the ppb level, with RSD values lower than 15%. The proposed methods were successfully applied to clinical and forensic cases, and good agreement of results was obtained compared to conventional methods.


Assuntos
Análise Química do Sangue/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Urina/química , Analgésicos Opioides/química , Benzodiazepinas/química , Humanos , Estrutura Molecular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
J Sep Sci ; 34(16-17): 2232-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21648080

RESUMO

A method coupling spin column extraction with gas chromatography-mass spectrometry was developed for the simultaneous extraction of acidic and basic drugs from urine. Benzodiazepines, local anaesthetics, antidepressants, and barbiturates were used as model drugs. Sample loading, washing, and elution of the target drugs were accomplished by centrifugation of the column. In this study, mixed-mode monolithic silica bonded with a C18 reversed-phase and a strong cation exchange phase was packed in a spin column. The pH of a urine sample (0.2 mL) was adjusted to 3 and the analytes adsorbed onto the column were eluted with 0.1 mL of MeOH containing 2% NH3; all the tested drugs were simultaneously extracted from urine. The recovery of the tested drugs was 65-123%. Up to a concentration of 2500 ng/mL of the target drugs in urine, a linear curve was observed (r(2)>0.996). The intra- and interday RSDs at three different concentrations in urine were 2.1-14.7%. For RSDs lower than 15%, the limits of detection were 1-25 ng/mL. The proposed method was successfully applied for clinical and forensic cases and the results thus obtained were in good agreement with those obtained by conventional methods.


Assuntos
Resinas de Troca de Cátion/química , Drogas Ilícitas/urina , Extração em Fase Sólida/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Drogas Ilícitas/química , Drogas Ilícitas/isolamento & purificação , Dióxido de Silício/química , Extração em Fase Sólida/instrumentação , Detecção do Abuso de Substâncias
10.
J Sep Sci ; 34(8): 901-24, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21394910

RESUMO

Monolith was first used as a material for chromatographic separation two decades ago and solid-phase extraction over 10 years, and since then, separation science has undergone a dramatic change owing to advancements in analytical technology. Recently, monolith has been modified to suit various devices for the extraction and enrichment of analytes in any matrices of environmental, food, and biological analyses. This approach has contributed to miniaturization and automation for sample preparation, and it can reduce the time and cost requirements of sample preparation. Recently, numerous applications have been demonstrated for online and inline preconcentration coupled with monolith, and many kinds of devices have been designed and developed for offline devices. In this review, these applications and devices are listed and discussed in reference to other fields.


Assuntos
Extração em Fase Sólida/instrumentação , Extração em Fase Sólida/métodos , Automação/métodos , Cromatografia Líquida/métodos , Eletroforese Capilar/métodos , Miniaturização/métodos
11.
Anal Bioanal Chem ; 400(1): 25-31, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21221537

RESUMO

We present a method based on monolitic spin column extraction and gas chromatography-mass spectrometry as an analytical method for screening diquat (DQ), paraquat (PQ), and fenitrothion in serum and urine. This method is useful for clinical and forensic toxicological analyses. Recovery of DQ, PQ, and fenitrothion from serum and urine, spiked at concentrations between 0.1, 2.5, 20, and 45 µg/ml, ranged from 51.3% to 106.1%. Relative standard deviation percentages were between 3.3% and 14.8%. Detection and quantitation limits for serum and urine were 0.025 and 0.05 µg/ml, respectively, for DQ, 0.1 and 0.1 µg/ml, respectively, for PQ, and 0.025 and 0.05 µg/ml, respectively, for fenitrothion. Therefore, these compounds can be detected and quantified in the case of acute poisoning.


Assuntos
Diquat/análise , Fenitrotion/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Paraquat/análise , Diquat/sangue , Diquat/urina , Fenitrotion/sangue , Fenitrotion/urina , Humanos , Limite de Detecção , Paraquat/sangue , Paraquat/urina , Padrões de Referência , Reprodutibilidade dos Testes
12.
Anal Chim Acta ; 661(1): 42-6, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20113714

RESUMO

A simple, sensitive, and specific method with gas chromatography-mass spectrometry was developed for simultaneous extraction and derivatization of amphetamines (APs) and 3,4-methylenedioxyamphetamines (MDAs) in human urine by using a monolithic silica spin column. All the procedures, such as sample loading, washing, and elution were performed by centrifugation. APs and MDAs in urine were adsorbed on the monolithic silica and derivatized with propyl chloroformate in the column. Methamphetamine-d(5) was used as an internal standard. The linear ranges were 0.01-5.0 microg mL(-1) for methamphetamine (MA) and 3,4-methylenedioxymethamphetamine (MDMA) and 0.02-5.0 microg mL(-1) for amphetamine (AP) and 3,4-methylenedioxyamphetamine (MDA) (coefficient of correlation > or = 0.995). The recovery of APs and MDAs in urine was 84-94%, and the relative standard deviation of the intra- and interday reproducibility for urine samples containing 0.1, 1.0, and 4.0 microg mL(-1) of APs and MDAs ranged from 1.4% to 13.6%. The lowest detection limit (signal-to-noise ratio > or = 3) in urine was 5 ng mL(-1) for MA and MDMA and 10 ng mL(-1) for AP and MDA. The proposed method can be used to perform simultaneous extraction and derivatization on spin columns that have been loaded with a small quantity of solvent by using centrifugation.


Assuntos
3,4-Metilenodioxianfetamina/urina , Anfetaminas/urina , Métodos Analíticos de Preparação de Amostras/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Dióxido de Silício/química , Humanos , Limite de Detecção , Estrutura Molecular
13.
J Chromatogr A ; 1208(1-2): 71-5, 2008 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-18790482

RESUMO

To overcome the limitations of solid-phase extraction, we developed a device comprising a spin column packed with octadecyl silane-bonded monolithic silica for extracting amphetamines and methylenedioxyamphetamines from urine. Urine (0.5mL), buffer (0.4mL), and methoxyphenamine (internal standard) were directly put into the preactivated column. The column was centrifuged (3000rpm, 5min) for sample loading and washed. The adsorbed analytes were eluted and analyzed by high-performance liquid chromatography, without evaporation. The results were as follows: linear curves (drug concentrations of 0.2-20microg/mL); correlation coefficients >0.99; detection limit, 0.1microg/mL. The proposed method is not only useful for drugs from biological materials but also highly reproducible for the analysis of these drugs in urine.


Assuntos
Anfetaminas/urina , Métodos Analíticos de Preparação de Amostras , Cromatografia Líquida de Alta Pressão/métodos , Anfetaminas/isolamento & purificação , Concentração de Íons de Hidrogênio , Dióxido de Silício/química
14.
J Chromatogr B Analyt Technol Biomed Life Sci ; 872(1-2): 186-90, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18657485

RESUMO

A simple, sensitive, and specific liquid chromatography-mass spectrometry (LC-MS) method for simultaneous determination of dibucaine and naphazoline from serum was developed and validated. The extraction procedure was performed using a monolithic silica spin column. Chromatographic separation of dibucaine and naphazoline was achieved on a C(18) reverse phase column with a mobile phase gradient (mobile phase A: 10 mM ammonium formate and mobile phase B: acetonitrile) at a flow rate of 0.2 mL/min. LC-MS was operated under the selective ion monitoring mode using the electrospray ionization technique in the positive mode. The retention times for naphazoline, dibucaine, and the internal standard (IS) were 6.7, 7.8, and 8.0 min, respectively. A linear graph was obtained for dibucaine and naphazoline with correlation coefficients >0.998 for all analytes by this method. The limit of quantification of dibucaine and naphazoline was 10 and 25 ng/mL, respectively. The mean recoveries were greater than 70%. Both compounds were stable under conditions of short-term storage, long-term storage as well as after freeze-thaw cycles. Monolithic spin column extraction and LC-MS analysis enabled the separation of dibucaine and naphazoline within 20 min.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Dibucaína/sangue , Nafazolina/sangue , Espectrometria de Massas por Ionização por Electrospray/métodos , Idoso , Idoso de 80 Anos ou mais , Calibragem , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Artigo em Inglês | MEDLINE | ID: mdl-18417428

RESUMO

A simple, rapid, sensitive, and specific liquid chromatography-mass spectrometry (LC-MS) method was developed and validated for the quantification of amitraz and its metabolite in human serum. Both the compounds were extracted using monolithic silica spin columns with acetonitrile. The chromatographic separation was performed on a reverse-phase C(18) column with a mobile phase of 10 mM ammonium formate-acetonitrile. The protonated analyte was quantitated in positive ionization by mass spectrometry. The method was validated over the concentration range of 25-1000 ng/ml for amitraz and its metabolite in human serum. For both compounds, the limit of detection was 5 ng/ml. The method was applied to serum samples taken from an attempted suicide patient, and only small volumes of serum were required for the simultaneous determination of these compounds.


Assuntos
Cromatografia Líquida/métodos , Inseticidas/sangue , Espectrometria de Massas/métodos , Toluidinas/sangue , Adulto , Calibragem , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dióxido de Silício
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