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1.
Regul Toxicol Pharmacol ; 128: 105097, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34902532

RESUMO

In forensic toxicology, a marker of street heroin use is urgent especially in the absence of urinary 6-monoacetylmorphine. ATM4G, the Glucuronide of Acetylated product of Thebaine compound 4 Metabolite (ATM4), arising from byproducts of street heroin synthesis has been considered as a useful marker in some European studies. However, whether ATM4G is a universal marker particularly in Southeast Asia due to 'street' heroin with high purity, it's still unclear. To investigate putative markers for different regions, ATM4G and other metabolites including the Acetylated product of Thebaine compound 3 Metabolite (ATM3) and thebaol, also originated from thebaine were detected in 552 urine samples from heroin users in Taiwan. Results were compared with that from samples collected in the UK and Germany. Only a sulfo-conjugate of ATM4, ATM4S, was detected in 28 Taiwanese users using a sensitive MS3 method whilst out of 351 samples from the UK and Germany, ATM4G was present in 91. Thebaol-glucuronide was first time detected in 118. No markers were detected in urine following herbal medicine use or poppy seed ingestion. The presence of ATM4S/ATM4G might be affected by ethnicities and heroin supplied in regions. Thebaol-glucuronide is another putative marker with ATM4G and ATM4S for street heroin use.


Assuntos
Toxicologia Forense/métodos , Glucuronídeos/urina , Heroína/metabolismo , Detecção do Abuso de Substâncias/métodos , Sudeste Asiático , Europa (Continente) , Cromatografia Gasosa-Espectrometria de Massas/métodos , Heroína/urina , Humanos , Derivados da Morfina/urina , Tebaína/urina
2.
Pathogens ; 11(5)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35631107

RESUMO

Early administration of proper antibiotics is considered to improve the clinical outcomes of Staphylococcus aureus bacteremia (SAB), but routine clinical antimicrobial susceptibility testing takes an additional 24 h after species identification. Recent studies elucidated matrix-assisted laser desorption/ionization time-of-flight mass spectra to discriminate methicillin-resistant strains (MRSA) or even incorporated with machine learning (ML) techniques. However, no universally applicable mass peaks were revealed, which means that the discrimination model might need to be established or calibrated by local strains' data. Here, a clinically feasible workflow was provided. We collected mass spectra from SAB patients over an 8-month duration and preprocessed by binning with reference peaks. Machine learning models were trained and tested by samples independently of the first six months and the following two months, respectively. The ML models were optimized by genetic algorithm (GA). The accuracy, sensitivity, specificity, and AUC of the independent testing of the best model, i.e., SVM, under the optimal parameters were 87%, 75%, 95%, and 87%, respectively. In summary, almost all resistant results were truly resistant, implying that physicians might escalate antibiotics for MRSA 24 h earlier. This report presents an attainable method for clinical laboratories to build an MRSA model and boost the performance using their local data.

3.
Front Oncol ; 11: 828314, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071023

RESUMO

BACKGROUND: The unusual high dialysis prevalence and upper urinary tract urothelial carcinoma (UTUC) incidence in Taiwan may attribute to aristolochic acid (AA), which is nephrotoxic and carcinogenic, exposure. AA can cause a unique mutagenic pattern showing A:T to T:A transversions (mutational Signature 22) analyzed by whole exome sequencing (WES). However, a fast and cost-effective tool is still lacking for clinical practice. To address this issue, we developed an efficient and quantitative platform for the quantitation of AA and tried to link AA detection with clinical outcomes and decipher the genomic landscape of UTUC in Taiwan. PATIENTS AND METHODS: We recruited 61 patients with de novo onset of UTUC after kidney transplantation who underwent radical nephroureterectomy. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) platform was developed for the quantitation of AA. Pearson's chi-square test, Kaplan-Meier method, and Cox proportional hazard model were utilized to assess the correlations among AA detection, clinicopathological characteristics, and clinical outcomes. Seven tumors and seven paired normal tissues were sequenced using WES (approximately 800x sequencing depth) and analyzed by bioinformatic tool. RESULTS: We found that high level of 7-(deoxyadenosin-N6-yl)aristolactam I (dA-AL-I) detected in paired normal tissues was significantly correlated with fast UTUC initiation times after renal transplantation (p = 0.035) and with no use of sirolimus (p = 0.046). Using WES analysis, we further observed that all tumor samples were featured by Signature 22 mutations, apolipoprotein B mRNA-editing enzyme, catalytic polypeptide (APOBEC)-associated gene mutations, p53 mutations, no fibroblast growth factor receptor 3 (FGFR3) mutation, and high tumor mutation burden (TMB). Especially, mammalian target of rapamycin (mTOR) activation predominated in dA-AL-I-detected samples compared with those without dA-AL-I detection and might be associated with UTUC initiation through cell proliferation and suppression of UTUC progression via autophagy inhibition. CONCLUSION: Accordingly, dA-AL-I detection can provide more direct evidence to AA exposure and serve as a more specific predictive and prognostic biomarker for patients with de novo onset of UTUC after kidney transplantation.

4.
PLoS One ; 11(9): e0161720, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27598341

RESUMO

Telomeres shorten with physiological aging but undergo substantial restoration during cancer immortalization. Increasingly, cancer studies utilize the archive of formalin-fixed, paraffin-embedded (FFPE) tissues in diagnostic pathology departments. Conceptually, such studies would be confounded by physiological telomere attrition and loss of DNA integrity from prolonged tissue storage. Our study aimed to investigate these two confounding factors. 145 FFPE tissues of surgically-resected, non-diseased appendixes were retrieved from our pathology archive, from years 2008 to 2014. Cases from 2013 to 2014 were categorized by patient chronological age (0-20 years, 21-40 years, 41-60 years, > 60 years). Telomere lengths of age categories were depicted by telomere/chromosome 2 centromere intensity ratio (TCR) revealed by quantitative fluorescence in situ hybridization. Material from individuals aged 0-20 years from years 2013/2014, 2011/2012, 2009/2010, and 2008 were compared for storage effect. Telomere integrity was assessed by telomere fluorescence intensity (TFI). Epithelial TCRs (mean ± SD) for the respective age groups were 4.84 ± 2.08, 3.64 ± 1.21, 2.03 ± 0.37, and 1.93 ± 0.45, whereas corresponding stromal TCRs were 5.16 ± 2.55, 3.84 ± 1.36, 2.49 ± 1.20, and 2.93 ± 1.24. A trend of inverse correlation with age in both epithelial and stromal tissues is supported by r = -0.69, p < 0.001 and r = -0.42, p < 0.001 respectively. Epithelial TFIs (mean ± SD) of years 2013/2014, 2011/2012, 2009/2010 and 2008 were 852.60 ± 432.46, 353.04 ± 127.12, 209.24 ± 55.57 and 429.22 ± 188.75 respectively. Generally, TFIs reduced with storage duration (r = -0.42, p < 0.001). Our findings agree that age-related telomere attrition occurs in normal somatic tissues, and suggest that an age-based reference can be established for telomere studies on FFPE tissues. We also showed that FFPE tissues archived beyond 2 years are suboptimal for telomere analysis.


Assuntos
Envelhecimento/genética , Homeostase do Telômero/genética , Adulto , Idoso , Envelhecimento/patologia , DNA/genética , Feminino , Formaldeído , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Inclusão em Parafina , Manejo de Espécimes , Telômero
5.
PLoS One ; 11(12): e0168238, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27936200

RESUMO

[This corrects the article DOI: 10.1371/journal.pone.0161720.].

6.
Sci Rep ; 6: 33789, 2016 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-27694951

RESUMO

Increasing evidence indicates that the neutrophil to lymphocyte ratio (NLR) is a useful biomarker of long-term outcomes in patients with cholangiocarcinoma. However, the prognostic role of NLR in patients with cholangiocarcinoma remains unclear. Thus, the current meta-analysis was undertaken to clarify the correlation between NLR and overall survival (OS) in cholangiocarcinoma, and a comprehensive literature research was conducted to understand the association of NLR and prognosis of cholangiocarcinoma. The hazard ratio (HR) with 95% confidence interval (CI) was used to assess OS. The synthesized HR of 1.449 (95% CI: 1.296-1.619, P < 0.001) indicated that a high NLR had an unfavourable effect on OS. Overall, this meta-analysis suggested that elevated preoperative NLR is associated with poorer rates of survival in cholangiocarcinoma patients.


Assuntos
Neoplasias dos Ductos Biliares , Biomarcadores Tumorais/sangue , Colangiocarcinoma , Linfócitos , Neutrófilos , Neoplasias dos Ductos Biliares/sangue , Neoplasias dos Ductos Biliares/mortalidade , Colangiocarcinoma/sangue , Colangiocarcinoma/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Contagem de Linfócitos , Masculino , Taxa de Sobrevida
7.
Anal Chim Acta ; 946: 1-8, 2016 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-27823666

RESUMO

An advantage of differential mobility spectrometry (DMS) is it provides an orthogonal mechanism to mass spectrometry (MS). The DMS-MS/MS detects analytes in the gas phase on the basis of differences in ion mobility in low and high electric fields, which makes DMS-MS/MS an alternative to chromatographic separation-MS. One drawback of DMS is its limited resolution and sensitivity, especially for detecting small molecules when using a nonpolar inert gas as the carrier gas. The present work has evaluated the effects on peak capacity of adding chemical modifiers to inert carrier gases (nitrogen, helium, argon and carbon dioxide). Use of a methanol-helium mixture gave improvements in both separation and sensitivity. Nine structurally similar amphetamine-type stimulants were determined in urine without pretreatment of the samples before analysis. After optimization of carrier gas, nature and concentration of chemical modifier, and DMS temperature, limits of detection ranging from 1.1 to 2.7 ng mL-1, with a linear range of three orders of magnitude (5-5000 ng mL-1) were achieved. Precision was <15% and the accuracy of the quality control samples was 87.6-113.7%. For the quantitation of urine samples from drug abusers, data obtained using DMS-MS/MS showed reasonable agreement (within ±19.5%) with that obtained using LC-MS/MS. The analysis time for DMS-MS/MS was only 1.1 min and a paired sample t-test between the two methods gave a p-value of 0.0894, which indicates that DMS-MS/MS is a reliable method, with comparable precision and sensitivity to LC-MS/MS.


Assuntos
Anfetamina/urina , Estimulantes do Sistema Nervoso Central/urina , Espectrometria de Massas em Tandem/métodos , Urinálise/métodos , Anfetamina/química , Anfetamina/isolamento & purificação , Estimulantes do Sistema Nervoso Central/química , Estimulantes do Sistema Nervoso Central/isolamento & purificação , Cromatografia Líquida , Humanos , Metanol/química , Nitrogênio/química , Temperatura
8.
Singapore Med J ; 57(3): 118-24; quiz 125, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26996216

RESUMO

The Ministry of Health (MOH) has developed the clinical practice guidelines on Prevention, Diagnosis and Management of Tuberculosis to provide doctors and patients in Singapore with evidence-based treatment for tuberculosis. This article reproduces the introduction and executive summary (with recommendations from the guidelines) from the MOH clinical practice guidelines on Prevention, Diagnosis and Management of Tuberculosis, for the information of SMJ readers. The chapters and page numbers mentioned in the reproduced extract refer to the full text of the guidelines, which are available from the Ministry of Health website: http://www.moh.gov.sg/content/moh_web/healthprofessionalsportal/doctors/guidelines/cpg_medical.html. The recommendations should be used with reference to the full text of the guidelines. Following this article are multiple choice questions based on the full text of the guidelines.


Assuntos
Gerenciamento Clínico , Medicina Baseada em Evidências/métodos , Governo , Guias de Prática Clínica como Assunto , Tuberculose , Humanos , Morbidade/tendências , Singapura/epidemiologia , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/prevenção & controle
9.
Food Chem ; 185: 377-82, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25952882

RESUMO

An up-and-down-shaker-assisted dispersive liquid-liquid microextraction (UDSA-DLLME) method coupled with gas chromatography-mass spectrometry was developed for the determination of fungicides (cyprodinil, procymidone, fludioxonil, flusilazole, benalaxyl, and tebuconazole) in wine. The developed method requires 11 µL of 1-octanol without the need for dispersive solvents. The total extraction time was approximately 3 min. Under optimum conditions, the linear range of the method was 0.05-100 µg L(-1) for all fungicides and the limit of detection was 0.007-0.025 µg L(-1). The absolute and relative recoveries were 31-83% and 83-107% for white wine, respectively, and 32-85% and 83-108% for red wine, respectively. The intra-day and inter-day precision were 0.5-7.5% and 0.7-6.1%, respectively. Our developed method had good sensitivity and high extraction efficiency. UDSA-DLLME is a desirable method in terms of performance and speed.


Assuntos
Fungicidas Industriais/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Líquida/métodos , Vinho/análise , Limite de Detecção
10.
J Agric Food Chem ; 62(37): 9059-65, 2014 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-25152072

RESUMO

A sample preparation method, dispersive liquid-liquid microextraction assisted by an emulsion with low concentration of a surfactant in water and dispersed solvent coupled with gas chromatography-mass spectrometry, was developed for the analysis of the fungicides cyprodinil, procymidone, fludioxonil, flusilazole, benalaxyl, and tebuconazole in wine. A microsyringe was used to withdraw and discharge a mixture of extraction solvent and 240 µL of an aqueous solution of Triton X-100 (the dispersed agent) four times within 10 s to form a cloudy emulsion in the syringe. This emulsion was then injected into a 5 mL wine sample spiked with all of the above fungicides. The total extraction time was approximately 0.5 min. Under optimum conditions using 1-octanol (12 µL) as extraction solvent, the linear range of the method in analysis of all six fungicides was 0.05-100 µg L(-1), and the limit of detection ranged from 0.013 to 0.155 µg L(-1). The absolute recoveries (n = 3) and relative recoveries (n = 3) were 30-83 and 81-108% for white wine at 0.5, 5, and 5 µg L(-1), and 30-92 and 81-110% for red wine, respectively. The intraday (n = 7) and interday (n = 6) relative standard deviations ranged from 4.4 to 8.8% and from 4.3 to 11.2% at 0.5 µg L(-1), respectively. The method achieved high enrichment factors. It is an alternative sample preparation technique with good performance.


Assuntos
Emulsões , Fungicidas Industriais/análise , Microextração em Fase Líquida/métodos , Tensoativos , Vinho/análise , Cromatografia Gasosa-Espectrometria de Massas , Sensibilidade e Especificidade , Solventes , Água
11.
Phytomedicine ; 20(1): 3-8, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23083815

RESUMO

BACKGROUND AND AIM: Curcumin, an active component derived from dietary spice turmeric (Curcuma longa), has been demonstrated antihyperglycemic, antiinflammatory and hypocholesterolemic activities in obesity and diabetes. These effects are associated with decreased level of circulating free fatty acids (FFA), however the mechanism has not yet been elucidated. The flux of FFA and glycerol from adipose tissue to the blood stream primarily depends on the lipolysis of triacylglycerols in the adipocytes. Adipocyte lipolysis is physiologically stimulated by catecholamine hormones. Tumor necrosis factor-α (TNFα) stimulates chronic lipolysis in obesity and type 2 diabetes. In this study, we examined the role of curcumin in inhibiting lipolytic action upon various stimulations in 3T3-L1 adipocytes. METHODS: Glycerol release from TNFα or isoproterenol-stimulated 3T3-L1 adipocytes in the absence or presence of curcumin was determined using a colorimetric assay (GPO-Trinder). Western blotting was used to investigate the TNFα-induced phosphorylation of MAPK and perilipin expression. Fatcake and cytosolic fractions were prepared to examine the isoproterenol-stimulated hormone-sensitive lipase translocation. RESULTS: Treatment with curcumin attenuated TNFα-mediated lipolysis by suppressing phosphorylation of extracellular signal-related kinase 1/2 (ERK1/2) and reversing the downregulation of perilipin protein in TNFα-stimulated adipocytes (p<0.05). The acute lipolytic response to adrenergic stimulation of isoproterenol was also restricted by curcumin (10-20 µM, p<0.05), which was compatible with reduced perilipin phosphorylation(29%, p<0.05) and hormone-sensitive lipase translocation(20%, p<0.05). CONCLUSIONS: This study provides evidence that curcumin acts on adipocytes to suppress the lipolysis response to TNFα and catecholamines. The antilipolytic effect could be a cellular basis for curcumin decreasing plasma FFA levels and improving insulin sensitivity.


Assuntos
Adipócitos/efeitos dos fármacos , Curcuma/química , Curcumina/farmacologia , Isoproterenol/farmacologia , Lipólise/efeitos dos fármacos , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Proteínas de Transporte/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Regulação para Baixo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Glicerol/metabolismo , Resistência à Insulina , Lipase/metabolismo , Camundongos , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Perilipina-1 , Fosfoproteínas/metabolismo , Fosforilação , Fitoterapia , Fator de Necrose Tumoral alfa/metabolismo
12.
Emerg Infect Dis ; 8(11): 1280-4, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12453356

RESUMO

We describe the implementation of a mandatory tuberculosis (TB) screening program that uses symptom screening and tuberculin skin testing in homeless shelters. We used the results of DNA fingerprinting of Mycobacterium tuberculosis isolates to evaluate the effect of the program on TB incidence and transmission. After the program was implemented, the proportion of cases among homeless persons detected by screening activities increased, and the estimated TB incidence decreased from 510 to 121 cases per 100000 population per year. Recent transmission, defined by DNA fingerprinting analysis as clustered patterns occurring within 2 years, decreased from 49% to 14% (p=0.03). Our results suggest that the shelter-based screening program decreased the incidence of TB by decreasing its transmission among the homeless.


Assuntos
Pessoas Mal Alojadas , Programas de Rastreamento , Teste Tuberculínico , Tuberculose/diagnóstico , Tuberculose/transmissão , Colorado/epidemiologia , Impressões Digitais de DNA , Humanos , Incidência , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Fatores de Risco , Fatores de Tempo , Tuberculose/epidemiologia , Tuberculose/microbiologia
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