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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(3): 755-9, 2017 Mar.
Artigo em Zh, Inglês | MEDLINE | ID: mdl-30148562

RESUMO

As a wildly used herbicide, Atrazine is mainly produced in China. In order to strengthen the routine detection of Atrazine exposure concentration and protect the health of occupational contact workers, it's of great importance to develop on-site rapid detection method. A self-assembled near infrared spectrometer was used to record spectra of laboratory prepared atrazine solutions with concentration range from 10 to 1 000 mg·L-1. The influences of different pretreatment methods, such as multiplicative scatter correction, standard normal variate, first order derivative (D1), second order derivative and their combinations, different variable selection methods, such as competitive adaptive reweighted sampling (CARS) and genetic algorithm (GA), different regression methods, such as partial least square (PLS) and support vector regression(nu-SVR), on the model prediction accuracy were investigated. Results show that D1 is the best pretreatment method; GA obtain better results than CARS on selecting highly related spectral variables; nu-SVR model perform better than PLS model. The nu-SVR model constructed with 16 spectral variables selected by GA obtained the best results, whose coefficient of determination for calibration, the coefficient of determination for validation, root mean square error of calibration, root mean square error of validation (RMSEV) and residual validation deviation (defined as SD/RMSEV where SD denotes standard deviation) are 1, 0.99, 17.54 mg·L-1, 25.42 mg·L-1 and 11.43, respectively. These results indicate near infrared spectroscopy combined with chemometrics has great potential to quantify Atrazine concentration at workplace. This research explores the feasibility of quantification Atrazine at workplace with near infrared spectroscopy for the first time, which has great reference value for similar work in the future.


Assuntos
Atrazina/análise , Espectroscopia de Luz Próxima ao Infravermelho , Local de Trabalho , Calibragem , China , Análise dos Mínimos Quadrados
2.
Biomed Environ Sci ; 26(6): 513-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23816588

RESUMO

This study aims to establish the occupational exposure limit (OEL) in the air for workplace of warfarin based on the available toxicological studies and field investigations by using questionnaire and air monitoring. The clinical therapeutic dose was used as lowest observed effect level (LOEL), and no observed effect level (NOEL) was achieved by using a safety factor. The highest concentration of warfarin monitored in the worksite of centrifuge washing, drying and packing were 0.029 mg/m3, 0.051 mg/m3 respectively, which did not exceed the OEL 0.1 mg/m3 recommended by NIOSH and ACGIH. Considering its feasibility for enforcement and protection for workers, we recommend OEL 0.1 mg/m3 of warfarin in China.


Assuntos
Anticoagulantes/toxicidade , Exposição Ocupacional/normas , Varfarina/toxicidade , China , Humanos , Fatores de Risco
3.
Artigo em Zh | MEDLINE | ID: mdl-24053969

RESUMO

OBJECTIVE: To establish a method for determining brodifacoum in workplace air by high-performance liquid chromatography (HPLC). METHODS: Brodifacoum in workplace air was collected with a polytetrafluoroethylene filter and desorbed by mixed solution of methanol and dichloromethane (20:80, V:V), and was then separated using an ODS column and determined by an ultraviolet detector; retention time was used for identification, and peak area was used for quantification. RESULTS: The concentration of brodifacoum showed a linear relationship with peak area within 0.2∼10.0 µg/ml; the elution efficiency was 91.6%∼95.1%; the detection limit was 0.08 µg/ml (injection volume: 20 µl eluate); the minimum detectable concentration was 0.000 67 mg/m(3) (calculated by 240 L air sample). CONCLUSION: This HPLC method is convenient and simple for air collection and sample preparation and meets the methodological requirements. Therefore, this method can be used for the determination of brodifacoum in workplace air.


Assuntos
4-Hidroxicumarinas/análise , Poluentes Ocupacionais do Ar/análise , Cromatografia Líquida de Alta Pressão/métodos , Ar/análise , Local de Trabalho
4.
Artigo em Zh | MEDLINE | ID: mdl-22808549

RESUMO

OBJECTIVE: A determination method of brodifacoum in rat plasma with bromadiolone as an internal standard was developed. METHODS: A volume of 10 microl internal standard (bromadiolone) was added into rat plasma, and then extracted by 0.5 ml of acetonitrile by shaking for 2 min. The residue was dissolved with 200 microl of mobile phase after centrifugation for 10 min, and evaporation to dryness by Nitrogen blowing. A C18 column and PDA detector were used for separating and detecting. The wavelength was 254 nm, the flow rate was 1.0 ml/min, and the injection volume was 20 microl. RESULTS: The liner range was 1.0-20 microg/ml, and the correlation coefficient was 0.9992. The detection limit was 0.3 microg/ml in plasma (S/N=3). The intra-assay and inter-assay coefficients of variation were 1.89%-2.45% and 2.51%-3.61% respectively. The recoveries in plasma at levels of low, middle and high concentrations were (80.8 +/- 3.1)%, (81.8 +/- 2.7)% and (87.9 +/- 3.6)% (n=6), respectively. The accuracies were 84.1%-91.5% and 86.7%-93.2%, respectively. CONCLUSION: This method is simple, fast and accurate for the determination of brodifacoum in rat plasma.


Assuntos
4-Hidroxicumarinas/sangue , Cromatografia Líquida de Alta Pressão , Plasma/química , Animais , Ratos
5.
Planta Med ; 77(17): 1924-31, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21728150

RESUMO

Seven new compounds, including four lignans, (+)-(8S,8'S)-9,9'-dibenzoylsecoisolariciresinol (1), (+)-(8S*,8'R*)-4,4'-dimethyloxomatairesinol (2), (+)-(7S*,8R*,8'R*,9'S*)-9'-n-butoxytsugacetal (3), and pseudolarkaemin A (4), a pyronane glycoside, pseudolarkaemin B (5), an ent-beyerene glycoside, pseudolarkaemin C (6), and a triterpene, 25-epi-pseudolarolide Q (7), along with 25 known compounds (8­32) were isolated from the twigs of Pseudolarix kaempferi. Their structures were elucidated mainly by the analysis of their NMR and MS data. Pseudolarolide C acid (24) was isolated for the first time as a natural product. All compounds were evaluated for antimicrobial activity against Candida albicans and Staphylococcus aureus, and cytotoxic activity against K562, HT-29, B16, BGC-823, BEL-7402, SGC-7901, U251, and A549 cancer cell lines were assayed. Results indicated that the new compounds 3, 7, and some known compounds showed antimicrobial and cytotoxic activities.


Assuntos
Anti-Infecciosos/farmacologia , Glicosídeos/farmacologia , Lignanas/farmacologia , Pinaceae/química , Extratos Vegetais/farmacologia , Terpenos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glicosídeos/química , Glicosídeos/isolamento & purificação , Humanos , Lignanas/química , Lignanas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Medicina Tradicional Chinesa , Testes de Sensibilidade Microbiana , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas Medicinais/química , Staphylococcus aureus/efeitos dos fármacos , Terpenos/química , Terpenos/isolamento & purificação
6.
Curr Med Sci ; 40(4): 597-601, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32767260

RESUMO

In late December 2019, COVID-19 was firstly recognized in Wuhan, China and spread rapidly to all of the provinces of China. The West Campus of Wuhan Union Hospital, the designated hospital to admit and treat the severe and critically ill COVID-19 cases, has treated a large number of such patients with great success and obtained lots of valuable experiences based on the Chinese guideline (V7.0). To standardize and share the treatment procedures of severe and critically ill cases, Wuhan Union Hospital has established a working group and formulated an operational recommendation, including the monitoring, early warning indicators, and several treatment principles for severe and critically ill cases. The treatment experiences may provide some constructive suggestions for treating the severe and critically ill COVID-19 cases all over the world.


Assuntos
Betacoronavirus , Infecções por Coronavirus/terapia , Pneumonia Viral/terapia , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticoagulantes/uso terapêutico , Antivirais/uso terapêutico , COVID-19 , Teste para COVID-19 , China/epidemiologia , Técnicas de Laboratório Clínico , Terapia Combinada , Comorbidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Estado Terminal , Dexametasona/uso terapêutico , Hospitais , Humanos , Imunização Passiva , Medicina Tradicional Chinesa , Pandemias , Pneumonia Viral/epidemiologia , Terapia Respiratória/métodos , SARS-CoV-2 , Tratamento Farmacológico da COVID-19 , Soroterapia para COVID-19
7.
Wei Sheng Yan Jiu ; 35(2): 230-1, 2006 Mar.
Artigo em Zh | MEDLINE | ID: mdl-16758979

RESUMO

OBJECTIVE: To establish a Reversed-Phase high performance liquid chromatography method for determination of plasma ropivacaine in dog. METHODS: The concentration of ropivacaine was assayed on Intertsil C18 column (4.6 mm x 250 mm, 5 microm)with a mobile phase consisting of methanol: H2O (50:50), the detection wavelength was 215nm and the flow rate was 1.4 ml/min. the column temperature was 20 degrees C and the sensitivity was 0.02 AUFS respectively. the volume of sample for detection is 10 microl. RESULTS: the linear range was 0.1-25 microg/ml (r = 0.9982). The recovery of ropivacaine was 91.2%-93.6%, RSD were 2.10%-3.40% (n=6). The detection limit was 0.05 microg/ml. the intra-day and interday precisions of assay for ropivacaine was 1.35%-2.88% and 1.80%-3.76%. CONCLUSION: This method is simple, rapid, accurate and convenient for determination of the concentration of ropivacaine in dog plasma.


Assuntos
Amidas/sangue , Anestésicos Locais/sangue , Cromatografia Líquida de Alta Pressão/métodos , Animais , Cães , Ropivacaina , Sensibilidade e Especificidade
8.
Phytochemistry ; 83: 63-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22959532

RESUMO

Labdane diterpene glycosides cathargyroside A and cathargyroside B, monoterpene glycosides vervenone-10-O-ß-D-glucopyranoside and vervenone-10-O-ß-D-apiofuranosyl-(1″→6')-ß-D-glucopyranoside, as well as lignan glycosides cedrusinin-4-O-α-L-rhamnopyranoside and (+)-cyclo-olivil-9'-O-ß-D-xylopyranoside, along with 39 known compounds, were obtained from the methanol extract of the twigs and leaves of Cathaya argyrophylla. These compounds were identified mainly by analyzing their NMR and MS data. Almost all of these compounds were hitherto unknown in this genus. The isolated compounds were screened against Candida albicans and Staphylococcus aureus for antimicrobial assay, and against K562, HT-29, BEL-7402, SGC-7901, B16, BGC-823, U251 and A549 cancer cell lines for cytotoxic activities. One compound showed antimicrobial activity against C. albicans, and four of them displayed cytotoxicity. Similarity analysis on the chemical constituents of the genera Cathaya, Picea and Pinus supported their close phylogenetic relationships.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Candida albicans/efeitos dos fármacos , Glicosídeos/farmacologia , Pinaceae/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glicosídeos/química , Glicosídeos/isolamento & purificação , Humanos , Lignanas/química , Testes de Sensibilidade Microbiana , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta/química , Caules de Planta/química , Relação Estrutura-Atividade , Terpenos/química
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