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1.
BMC Anesthesiol ; 23(1): 338, 2023 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-37803290

RESUMO

BACKGROUND: Epidural anesthesia (EA) is the regional anesthesia technique preferred over spinal anesthesia for pregnant women requiring cesarean section and post-operative pain control. EA failure requires additional sedation or conversion to general anesthesia (GA). This may be hazardous during sedation or GA conversion because of potentially difficult airways. Therefore, this retrospective study aimed to determine the risk factors for epidural failure during cesarean section anesthesia. METHODS: We retrospectively analyzed parturients who underwent cesarean section under EA and catheterization at the Chang Gung Memorial Hospital in Taiwan between January 1 and December 31, 2018. Patient data were collected from the medical records. EA failure was defined as the administration of any intravenous anesthetic at any time during a cesarean section, converting it into GA. RESULTS: A total of 534 parturients who underwent cesarean section were recruited for this study. Of them, 94 (17.6%) experienced EA failure during cesarean section. Compared to the patients with successful EA, those with EA failure were younger (33.0 years vs. 34.7 years), had received EA previously (60.6% vs. 37%), were parous (72.3% vs. 55%), and had a shorter waiting time (14.9 min vs. 16.5 min) (p < 0.05). Younger age (OR 0.91, 95% CI 0.86-0.95), history of epidural analgesia (OR 2.61, 95% CI 1.38-4.94), and shorter waiting time (OR 0.91, 95% CI 0.87-0.97) were estimated to be significantly associated with a higher risk of epidural anesthesia failure. CONCLUSION: The retrospective study found that parturients of younger age, previous epidural catheterization history, and inadequate waiting time may have a higher risk of EA failure. Previous epidural catheterization increased the risk of EA failure by 2.6-fold compared to patient with no history of catheterization.


Assuntos
Analgesia Epidural , Anestesia por Condução , Anestesia Epidural , Anestesia Obstétrica , Raquianestesia , Gravidez , Feminino , Humanos , Cesárea/efeitos adversos , Anestesia Epidural/efeitos adversos , Estudos Retrospectivos , Anestesia Obstétrica/efeitos adversos , Raquianestesia/efeitos adversos , Fatores de Risco
2.
J Org Chem ; 81(11): 4713-9, 2016 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-27137813

RESUMO

An efficient protocol for the synthesis of sulfonamides via the electrochemical oxidative amination of sodium sulfinates has been developed. The chemistry proceeds in a simple undivided cell employing a substoichiometric amount of NH4I that serves both as a redox catalyst and a supporting electrolyte; in this manner additional conducting salt is not required. A wide range of substrates, including aliphatic or aromatic secondary and primary amines, as well as aqueous ammonia, proved to be compatible with the protocol. Scale-up was possible, thereby demonstrating the practicality of the approach. The electrolytic process avoids the utilization of external oxidants or corrosive molecular iodine and therefore represents an environmentally benign means by which to achieve the transformation.

3.
J Org Chem ; 80(21): 11021-30, 2015 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-26444498

RESUMO

An effective Friedel-Crafts alkylation reaction of electron-rich aromatics with N-vinylamides, induced by electrochemically in situ-generated TBPA radical cation, has been developed; the resulting adducts are produced in good to excellent yields. In the "ex-cell" type electrolysis, TBPA is transformed to its oxidized form in situ and subsequently employed as an electron transfer reagent to initiate a cationic chain reaction. An easily recoverable and reusable polymeric ionic liquid-carbon black (PIL-CB) composite was also utilized as a supporting electrolyte for the electrochemical generation of TBPA cation radical, without sacrificing efficiency or stability after four electrolyses. Cyclic voltammetry analysis and the results of control experiments demonstrate that the reaction of electron-rich aromatics and N-vinylamides occurs via a cationic chain reaction, which takes place though an oxidative activation of a C-H bond of electron-rich aromatics instead of oxidation of the N-vinylamide as previously assumed.

4.
J Org Chem ; 80(2): 781-9, 2015 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-25458758

RESUMO

The indirect anodic oxidation of chalcone epoxides in the presence of electron-rich heteroarenes mediated by a triarylimidazole (Med) was investigated by cyclic voltammetry (CV) and controlled potential electrolysis. The CV results indicate that a homogeneous electron transfer between Med•+ and chalcone epoxides is facilitated by an electron-rich heteroarene that serves as an arylation reagent. The preparative scale electrolysis generated epoxide-ring-opened/Friedel­Crafts arylation products in moderate to good yields. The fact that only a catalytic amount of charge was required suggests that Med•+ initiates a chain reaction. In addition, overoxidation of the products is avoided even though their oxidation potential is less than that of the starting chalcone epoxides.


Assuntos
Chalconas/química , Imidazóis/química , Oxirredução , Catálise , Compostos de Epóxi , Estrutura Molecular
5.
Xenobiotica ; 45(11): 1030-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26153442

RESUMO

1. CYP2C19 is a highly polymorphic enzyme responsible for the metabolism of a wide range of clinical drugs. Alterations to the CYP2C19 gene contribute to the variability of CYP2C19 enzyme activity, which causes pharmacokinetics and drug efficacies to vary and adverse drug reactions to occur in different persons. Recently, we identified 24 novel CYP2C19 allelic variants in the Chinese Han population. The purpose of present study is to assess the impact of these newly found nucleotide mutations on the enzymatic activity of the CYP2C19 protein. 2. Dual-expression vectors were constructed and transiently transfected into 293FT cells. Forty-eight hours after transfection, cells were re-suspended and incubated with two typical probe substrates, omeprazole and S-mephenytoin, to determine the activities of each variant relative to the wild-type protein. 3. Immunoblotting results showed that the protein expression levels of the CYP2C19 variants were diverse. Enzymatic ability analysis showed that the variant 35FS exhibited no functional activity, and most of the other variants showed significantly decreased metabolic activities toward both omeprazole and S-mephenytoin compared with wild-type. 4. These findings greatly enrich the knowledge of biological effects of these newly found CYP2C19 mutations and aid the application of this knowledge to future individualized drug therapy in clinic.


Assuntos
Alelos , Povo Asiático/genética , Citocromo P-450 CYP2C19 , Mutação , Omeprazol/farmacocinética , Povo Asiático/etnologia , Linhagem Celular , China/etnologia , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C19/metabolismo , Feminino , Humanos , Masculino , Omeprazol/farmacologia
6.
J Org Chem ; 79(20): 9613-8, 2014 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-25255384

RESUMO

An electrochemically promoted coupling of benzoxazoles and amines has been developed, leading directly to the formation of 2-aminobenzoxazoles. The chemistry utilizes catalytic quantities of a tetraalkylammonium halide redox catalyst and is carried out under constant current conditions in a simple undivided cell. The use of excess chemical oxidant or large amounts of supporting electrolyte is avoided. This greatly simplifies the workup and isolation process and leads to a reduction in waste.


Assuntos
Benzoxazóis/química , Halogênios/química , Compostos de Amônio Quaternário/química , Aminação , Catálise , Estrutura Molecular , Oxirredução
7.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(1): 15-9, 2014 Jan.
Artigo em Zh | MEDLINE | ID: mdl-24520780

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of Chinese medicine (CM) intervention in the treatment of nonalcoholic steatohepatitis (NASH) from liver enzyme (ALT), imaging (the liver/spleen CT ratio) and syndrome scores, and to establish standard methods for diagnosis and therapeutic efficacy evaluation with characteristics of CM. METHODS: A multi-center, stratified randomized, parallel controlled, blindness-method evaluated, superiority trial was performed. Totally 204 patients were randomly allocated into two groups, 102 patients in the experimental group (treated with CM) and 102 patients in the control group [treated with Western medicine (WM)]. The alanine aminotransferase (ALT), liver/spleen CT ratio, and clinical symptoms were observed in both groups. RESULTS: Of the randomly allocated 204 cases from 4 hospitals, 3 patients were rejected, and 25 were lost. Totally 176 cases con- formed to the plan with complete follow-ups. After 3 months of treatment, syndrome scores and the improvement of partial clinical symptoms (fatigue and sallow complexion) were superior in the experimental group to those in the control group (P < 0.05). After 3 months of follow-up, the syndrome scores and improvement of partial clinical symptoms (fatigue and sallow complexion) were superior in the experimental group to those in the control group (P < 0.05). There was no statistical difference in improving liver enzymes or the liver/spleen CT ratio between the two groups (P > 0.05). There were 4 adverse reactions/adverse events in the two groups in the process of treatment, mainly covering drug-induced liver injury, diarrhea, and epigastric distension. Adverse reactions had nothing to do with CM treatment. CONCLUSIONS: Jianpi Shugan Recipe had obvious efficacy in treatment of NASH. It could remove the liver fat and play a role in anti-inflammation and liver protection. It also could improve the indices of liver enzymes and the liver/spleen CT ratio effectively, which was superior to Polyene Phosphatidylcholine Capsule (PPC) in improving clinical symptoms, especially for such symptoms as fatigue and sallow complexion.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Fitoterapia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Acta Pharmacol Sin ; 34(11): 1449-56, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24077631

RESUMO

AIM: Cytochrome P450 2C9 (CYP2C9) is a polymorphic enzyme that is responsible for the metabolism of approximately 15% of clinically important drugs. The aim of this study was to assess the catalytic characteristics of 37 CYP2C9 allelic isoforms found in Chinese Han population on the metabolism of tolbutamide in vitro. METHODS: The wild-type and 36 CYP2C9 variants were expressed in sf21 insect cells using a baculovirus-mediated expression system. Then the insect microsomes were prepared for assessing the metabolic characteristics of each variant toward the CYP2C9-specific drug substrate tolbutamide. RESULTS: Of 36 allelic variants tested, the intrinsic clearance values of 2 allelic isoforms (CYP2C9.36 and CYP2C9.51) were much higher than the wild-type CYP2C9.1 protein, 3 allelic isoforms (CYP2C9.11, CYP2C9.56 and N418T) exhibited similar intrinsic clearance values as the wild-type enzyme, whereas the other 31 variants showed significantly reduced intrinsic clearance values, ranging from 0.08% to 66.88%, for tolbutamide. CONCLUSION: Our study provides the most comprehensive data concerning the enzymatic activity of the CYP2C9 variants that are present in the Chinese Han population, and our data suggest that most of the carriers of these alleles might be paid more attention when using CYP2C9 mediated drugs clinically.


Assuntos
Alelos , Hidrocarboneto de Aril Hidroxilases/metabolismo , Microssomos/enzimologia , Tolbutamida/metabolismo , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Povo Asiático , China , Citocromo P-450 CYP2C9 , Humanos , Isoenzimas , Células Sf9 , Spodoptera
9.
Zhonghua Nan Ke Xue ; 19(4): 324-7, 2013 Apr.
Artigo em Zh | MEDLINE | ID: mdl-23678711

RESUMO

OBJECTIVE: To investigate the prevalence of benign prostatic hyperplasia (BPH) in Pingliang City of Gansu Province. METHODS: We performed a cross-sectional randomized study of 836 men aged > or = 40 years from 26 communities of Pingliang, obtained their IPSS, measured the prostate volume by transabdominal ultrasonography, recorded the maximum flow (Qmax) by uroflowmetry, and processed the data by one-way analysis of variance. RESULTS: Totally 820 subjects meeting the study criteria were included in the investigation. The men ranged in age from 40 to 83 years, averaging 61.5 years. The mean IPSS, prostate volume and Qmax were 9.3 +/- 7.8, (29.2 +/- 18.6) ml and (15.3 +/- 7.2) ml/s, respectively, all correlated with age. The prevalence of moderate-severe lower urinary tract symptoms (LUTS) was 46.8% (384/820). The prostate volume was > 20 ml in 63.5% (521/820), and Qmax <15 ml/s in 48.5% (398/805) of the subjects. The incidence rate of BPH, defined as IPSS >7, Qmax <15 ml/s and prostate volume > 20 ml, was 23.5% (193/820). CONCLUSION: Among the men aged > or = 40 years in Pingliang, LUTS and prostate volume were correlated positively, while Qmax negatively with age, and the prevalence of BPH was 23.5%.


Assuntos
Próstata/patologia , Hiperplasia Prostática/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Prevalência , Hiperplasia Prostática/diagnóstico
10.
J Photochem Photobiol B ; 234: 112534, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35905626

RESUMO

Mitochondrial transplantation (MT) is a new technology developed in recent years, which injects healthy mitochondria directly into damaged tissues or blood vessels to play a therapeutic role. This technology has been studied in many animal models of various diseases including myocardial ischemia, cerebral stroke, liver and lung injury, and even has been successfully used in the treatment of childhood heart disease. MT can quickly improve tissue function within a few minutes after injection. The speed with which MT improves tissue function is frequently questioned, for it is hard to understand how the whole mitochondrion transports to the damaged sites, enters cells and functions within such a short period of time. Are there small molecules of mitochondrial component responsible for the function of MT? To test this hypothesis, we established an ultra-violet (UV)-irradiated HeLa cell model. The results of colony formation, sulforhodamine B (SRB), and Hoechst 33342/PI double staining assay strongly indicated that MT exhibited a significant protective effect against UV irradiation damage. The UV irradiation-induced cell cycle arresting at S phase, apoptosis, mitochondrial membrane potential (MMP) decreasing, and the related apoptosis signaling factors p-IKKα, p-p65, I-κB and the activation of caspase3 were all reversed by MT treatments to some extent. The mechanisms of MT were evaluated through comparing the effect of thermal inactivation, ultrasonic crushing, and repeated freezing and thawing treatments on MT function. These results denied the above hypothesis that mitochondrial component may be responsible for MT, excluded the function of ATP, mtDNA and other small molecules, and indicated that the mitochondria structural integrity is essential. We also evaluated the effect of Ca2+ concentrations (1 and 1.8 mM) on MT, and the results showed no effect was found in this UV-irradiated HeLa cell model. Our data support a potent anti-UV irradiation effect of MT, and that structural integrity of the mitochondria is critical for its function.


Assuntos
Apoptose , Mitocôndrias , Animais , DNA Mitocondrial/genética , Células HeLa , Humanos , Potencial da Membrana Mitocondrial
11.
Zhonghua Nan Ke Xue ; 17(8): 722-5, 2011 Aug.
Artigo em Zh | MEDLINE | ID: mdl-21898996

RESUMO

OBJECTIVE: To investigate the prevalence of hyposexuality, erectile dysfunction (ED) and defective ejaculation (DE) in the old and middle-aged males in Pingliang area. METHODS: This investigation included 1 539 men aged > or = 50 years from 6 urban districts and 20 villages in the suburbs of Pingliang City, Gansu Province. We recorded and analyzed their scores on IIEF-5 and Brief Male Sexual Function Inventory for Urology (O'Leary 1995). RESULTS: A total of 1 230 subjects met the investigation criteria. They averaged 62.5 +/- 9.6 years of age (range 50-89 years), and were divided into four age groups: 50-59, 60-69, 70-79 and > or = 80 years. The mean scores on IIEF-5 were 0-25 (9.4 +/- 8.6), sexual desire 0-8 (2.3 +/- 2.1), and ejaculation 0-8 (3.6 +/- 3.0). Hyposexuality, ED and DE were defined as sexual desire score < or = 2, IIEF-5 score = 0-21, and ejaculation score < or = 2, respectively. Based on these criteria, the incidence rates of hyposexuality, ED and DE were 57.96%, 92.27% and 36.91%, respectively, with statistically significant differences among different age groups (P < 0.01). CONCLUSION: The prevalence of ED, hyposexuality and DE, particularly the incidence of ED, is positively correlated with the increase of age in the old and middle-aged males in Pingliang area.


Assuntos
Disfunção Erétil/epidemiologia , Disfunções Sexuais Psicogênicas/epidemiologia , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Humanos , Masculino , Transtornos Mentais/epidemiologia , Pessoa de Meia-Idade , Prevalência , Comportamento Sexual , Inquéritos e Questionários
12.
Medicine (Baltimore) ; 100(28): e26215, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34260521

RESUMO

OBJECTIVE: To explore whether rs4784227 polymorphism of CASC16 is correlated with risk of breast cancer. METHODS: Relevant studies up to December 24, 2020 were searched in PubMed, Embase, Web of Science, CNKI, VIP, and WANFANG databases. Data were analyzed by using Stata 12.0. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, and country-based subgroup analyses were conducted. Sensitivity analysis was conducted to assess the stability of the results. Publication bias was assessed by using the Egger regression asymmetry test and visualization of funnel plots. RESULTS: Seven case-control studies enrolling 4055 breast cancer cases and 4229 controls were included. rs4784227 was found significantly associated with increased risk of breast cancer in a dominant (OR = 1.301, 95% CI = 1.190-1.423, P < .001), a recessive (OR = 1.431, 95% CI = 1.216-1.685, P < .001), and an allele model (OR = 1.257, 95% CI = 1.172-1.348, P < .001), while an over-dominant model showed that rs4784227 was correlated with decreased breast cancer risk (OR = 0.852, 95% CI = 0.778-0.933, P = .001). CONCLUSION: The rs4784227 polymorphism of CASC16 gene is correlated with breast cancer susceptibility.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Neoplasias da Mama/genética , Transativadores/genética , Alelos , Povo Asiático , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , Fatores de Risco
13.
Org Biomol Chem ; 8(10): 2465-72, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20448907

RESUMO

The electrochemical oxidation of catechols leads to the formation of o-benzoquinones. This property has been applied to effectively synthesize alpha-arylated products of alpha-oxoketene N,N-acetals with a tetrahydropyrimidine ring.


Assuntos
Acetais/química , Catecóis/química , Etilenos/química , Cetonas/química , Pirimidinas/química , Eletroquímica , Eletrodos , Elétrons , Oxirredução , Especificidade por Substrato
14.
Molecules ; 15(3): 1903-17, 2010 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-20336021

RESUMO

Styrylquinoline derivatives are demonstrated to be HIV-1 integrase inhibitors. On the basis of our previous CoMFA analysis of a series of styrylquinoline derivatives, N-[(2-substituted-styryl)-5-chloro-8-hydroxyquinolin-7-yl]-benzenesulfonamide derivatives were designed and synthesized,and their possible HIV IN inhibitory activity was evaluated.


Assuntos
Inibidores de Integrase de HIV/síntese química , Inibidores de Integrase de HIV/farmacologia , Sulfonamidas/síntese química , Sulfonamidas/farmacologia , Avaliação Pré-Clínica de Medicamentos , Inibidores de Integrase de HIV/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Sulfonamidas/química
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 42(3): 323-9, 2010 Jun 18.
Artigo em Zh | MEDLINE | ID: mdl-20559410

RESUMO

OBJECTIVE: To describe the status of subjective well-being among junior high school students in a city of Jiangxi Province and to explore the relationship between family functioning and subjective well-being. To explore the relationship between growth environment and subjective well-being among junior high school students in the perspective of family functioning and to provide basis and data for the mental health education among junior high school students. METHODS: 630 students in a junior high school in Jiangxi Province were sampled by stratified cluster sampling, and 103 junior high school students from 18 villages were sampled by household survey. They were investigated by subjective well-being scale for adolescents and Family Assessment Device. RESULTS: (1)The overall subjective well-being of junior high school students was in the lower-middle level. Regarding all the dimensions of subjective well-being, they had the highest satisfaction on family and friendship, lowest academic satisfaction, low positive as well as passive emotion. (2)Girls had higher satisfaction on friendship and freedom than that of boys; children from families with more than one kids had more negative emotion than that of single child; boarding students had higher satisfaction on family, academics and freedom than that of non-boarding students; family residence and structure affected the satisfaction on family; grade and learning achievement affected some dimensions of subjective well-being among junior high school students. (3)Pearson correlation analysis and multiple linear regression analysis showed that some dimensions of family functioning were related to certain dimensions of subjective well-being among junior school students, and family functioning could predict the level of subjective well-being. CONCLUSION: The overall subjective well-being of junior high school students is in the lower-middle level, and further improving is needed. Family functioning has a great influence on junior school students' subjective well-being. Junior high school students who have healthy family functioning are more likely to have higher life satisfaction, and tend to experience higher subjective well-being.


Assuntos
Família , Saúde Mental/estatística & dados numéricos , Satisfação Pessoal , Inquéritos e Questionários , Adolescente , Criança , China , Feminino , Humanos , Masculino , Psicologia do Adolescente , Estudantes
16.
J Org Chem ; 74(16): 6386-9, 2009 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-19575534

RESUMO

An novel and convenient electrochemical approach was developed for the synthesis of indole derivatives from catechols and alpha-oxoheterocyclic ketene N,O-acetals. This method provides an environmentally benign access to fused indole derivatives containing active hydroxyls and carbonyl under mild reaction conditions.


Assuntos
Hidróxidos/química , Indóis/química , Indóis/síntese química , Água/química , Eletroquímica , Oxirredução
17.
Molecules ; 14(2): 868-83, 2009 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-19255545

RESUMO

4-Oxo-4H-quinolizine-3-carboxylic acid derivatives bearing sulfamido, carboxylamido, benzimidazole and benzothiazole substituents have been designed and synthesized. The structures of these new compounds were confirmed by (1)H-NMR, (13)C- NMR, IR and ESI (or HRMS) spectra. Compounds were screened for possible HIV integrase inhibitory activity.


Assuntos
Ácidos Carboxílicos , Inibidores de Integrase de HIV , Integrase de HIV/metabolismo , Quinolizinas , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/química , Ácidos Carboxílicos/metabolismo , Desenho de Fármacos , Inibidores de Integrase de HIV/síntese química , Inibidores de Integrase de HIV/química , Inibidores de Integrase de HIV/metabolismo , Humanos , Magnésio/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Quinolizinas/síntese química , Quinolizinas/química , Quinolizinas/metabolismo , Relação Estrutura-Atividade
18.
Food Chem ; 257: 382-387, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622226

RESUMO

Amantadine (AMD), a banned antiviral veterinary drug, is still being abused. This study developed a novel enzyme linked immunosorbent assay for the colorimetric detection of AMD involving DNA hybridization reaction and non-crosslinking gold nanoparticles (AuNPs) aggregation. Accordingly, the Primer 1-AuNPs-anti-AMD monoclonal antibody (mAb) could be captured by AMD artificial antigen on ELISA wells. Primer 2, which was complementary paired to Primer 1, was eventually added into the ELISA wells. After the hybridization reaction, the free Primer 2 in the supernatant was mixed with AuNPs and NaCl and induced a rapid color change of AuNPs. The lack of AMD in the sample resulted in capturing a substantial Primer 1-AuNPs-mAb complex and limited free Primer 2 in the supernatant. After adding NaCl, the color of AuNPs turned blue with limited Primer 2. This simple and visualized novel method had good sensitivity (0.033 µM) and exhibited a potential application for AMD screening on site.


Assuntos
Amantadina/análise , Ensaio de Imunoadsorção Enzimática/métodos , Ouro/química , Nanopartículas Metálicas/química , Amantadina/imunologia , Anticorpos Monoclonais/imunologia , Colorimetria , DNA/química , DNA/metabolismo , Hibridização de Ácido Nucleico
19.
Anal Chim Acta ; 998: 52-59, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29153086

RESUMO

Colloidal gold immunochromatographic assay (ICA) has poor sensitivity when used for Escherichia coli O157:H7 (E. coli O157:H7) detection. Eu (III)-doped polystyrene nanoparticle (EuNP) has a large range of stokes shift, long decay time, and wide excitation spectrum and narrow emission spectra. EuNP has been used as novel probe in ICA to improve sensitivity. In this study, carboxyl-modified EuNPs were prepared with different linkers. ICA based on EuNP, EuNP-6 carbon chain (CC) complex, EuNP-200CC complex, EuNP-1000CC complex, and EuNP-streptavidin (EuNP-SA) complex were systematically compared for the detection of E. coli O157:H7. Under optimized working conditions, the limits of detection (LOD) of EuNP-ICA, EuNP-6CC-ICA, EuNP-200CC-ICA, EuNP-1000CC-ICA, and EuNP-SA-ICA were 9.54 × 102, 1.59 × 102, 3.18 × 102, 2.98 × 102, and 1.08 × 102 colony-forming units (CFU) mL-1, respectively. The linear ranges of EuNP-ICA, EuNP-6CC-ICA, EuNP-200CC-ICA, EuNP-1000CC-ICA, and EuNP-SA-ICA were 6.36 × 102-1.59 × 105, 3.18 × 102-1.59 × 105, 6.36 × 102-1.59 × 105, 6.36 × 102-1.59 × 105, and 8.0 × 101-1.59 × 105 CFU mL-1, respectively. EuNP-SA-ICA exhibited the highest sensitivity and the widest linear range with good specificity, accuracy, and precision. It could be a promising analytical method for detecting E. coli O157:H7 in food samples. EuNP-SA-ICA may be a good model for detecting low concentrations of other food-borne pathogens.


Assuntos
Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Cromatografia de Afinidade/métodos , Escherichia coli O157/imunologia , Escherichia coli O157/isolamento & purificação , Európio/química , Nanopartículas/química , Poliestirenos/química
20.
Biosens Bioelectron ; 91: 95-103, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28006689

RESUMO

Label selection is a critical factor for improving the sensitivity of lateral flow assay. Time-resolved fluorescent nanobeads, fluorescent submicrospheres, quantum dots, and colloidal gold-based lateral flow assay (TRFN-LFA, FM-LFA, QD-LFA, and CG-LFA) were first systematically compared for the quantitative detection of ractopamine in swine urine based on competitive format. The limits of detection (LOD) of TRFN-LFA, FM-LFA, QD-LFA, and CG-LFA were 7.2, 14.7, 23.6, and 40.1pg/mL in swine urine samples, respectively. The sensitivity of TRFN-LFA was highest. In the quantitative determination of ractopamine (RAC) in swine urine samples, TRFN-LFA exhibited a wide linear range of 5pg/mL to 2500pg/mL with a reliable coefficient of correlation (R2=0.9803). Relatively narrow linear ranges of 10-500pg/mL (FM-LFA) and 25-2500pg/mL (QD-LFA and CG-LFA) were acquired. Approximately 0.005µg of anti-RAC poly antibody (pAb) was used in each TRFN-LFA test strip, whereas 0.02, 0.054, and 0.15µg of pAb were used in each of the FM-LFA, QD-LFA, and CG-LFA test strips, respectively. In addition, TRFN-LFA required the least RAC-BSA antigens and exhibited the shortest detection time compared with the other lateral flow assays. Analysis of the RAC in swine urine samples showed that the result of TRFN-LFA was consistent with that of liquid chromatography-tandem mass spectrometry (LC-MS/MS) and a commercial enzyme-linked immunosorbent assay (ELISA) kit.


Assuntos
Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Coloide de Ouro/química , Substâncias de Crescimento/urina , Fenetilaminas/urina , Pontos Quânticos/química , Animais , Técnicas Biossensoriais/instrumentação , Ensaio de Imunoadsorção Enzimática , Fluorescência , Imunoensaio/instrumentação , Imunoensaio/métodos , Limite de Detecção , Pontos Quânticos/ultraestrutura , Fitas Reagentes/análise , Suínos , Espectrometria de Massas em Tandem
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