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1.
Molecules ; 29(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474553

RESUMO

This paper reports an innovative study that aims to address key issues in the efficient recycling of wastepaper cellulose. The research team utilized the temperature-responsive upper critical solution temperature (UCST) polymer P(NAGA-b-DMA) in combination with the LytA label's affinity for choline analogs. This innovative approach enabled them to successfully develop a novel soluble immobilized enzyme, P(NAGA-b-DMA)-cellulase. This new enzyme has proven highly effective, significantly enhancing the degradation of wastepaper cellulose while demonstrating exceptional stability. Compared with the traditional insoluble immobilized cellulase, the enzyme showed a significant improvement in the pH, temperature stability, recycling ability, and storage stability. A kinetic parameter calculation showed that the enzymatic effectiveness of the soluble immobilized enzyme was much better than that of the traditional insoluble immobilized cellulase. After the immobilization reaction, the Michaelis constant of the immobilized enzyme was only increased by 11.5%. In the actual wastepaper degradation experiment, the immobilized enzyme was effectively used, and it was found that the degradation efficiency of wastepaper cellulose reached 80% of that observed in laboratory conditions. This novel, thermosensitive soluble immobilized cellulase can efficiently catalyze the conversion of wastepaper cellulose into glucose under suitable conditions, so as to further ferment into environmentally friendly biofuel ethanol, which provides a solution to solve the shortage of raw materials and environmental protection problems in the paper products industry.


Assuntos
Celulase , Enzimas Imobilizadas , Enzimas Imobilizadas/metabolismo , Celulose/metabolismo , Celulase/metabolismo , Temperatura , Polímeros , Hidrólise
2.
Am J Nephrol ; 54(7-8): 258-267, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37231821

RESUMO

INTRODUCTION: Discontinuation of renin-angiotensin-aldosterone system inhibitor (RAASi) is common after hyperkalemia. We evaluated the risk of kidney and mortality outcomes associated with RAASi discontinuation among patients with chronic kidney disease (CKD) and hyperkalemia. METHODS: We identified adult patients with CKD (eGFR <60 mL/min/1.73 m2) who experienced new-onset hyperkalemia (potassium ≥5.0 mEq/L) between 2016 and 2017 from Kaiser Permanente Southern California and followed them through 2019. We defined treatment discontinuation as having ≥90-day gap in refills of all RAASi within 3 months after hyperkalemia. We used multivariable Cox proportional hazards models to evaluate the association between RAASi discontinuation and the primary composite outcome of kidney (≥40% eGFR decline, dialysis, kidney transplant) or all-cause mortality. We evaluated cardiovascular events and recurrence of hyperkalemia as secondary outcomes. RESULTS: Among 5,728 patients (mean age 76 years), 13.5% discontinued RAASi within 3 months after new-onset hyperkalemia. During the median 2 years of follow-up, 29.7% had the primary composite outcome (15.5% with ≥40% eGFR decline, 2.8% dialysis or kidney transplant, 18.4% all-cause mortality). Patients who discontinued RAASi had a higher all-cause mortality compared with those who continued RAASi (26.7% vs. 17.1%) but had no differences in kidney outcomes, cardiovascular events, and recurrence of hyperkalemia. RAASi discontinuation was associated with a higher risk of kidney or all-cause mortality composite outcome (adjusted hazard ratio [aHR] 1.21, 95% CI: 1.06, 1.37) mainly driven by all-cause mortality (aHR: 1.34, 95% CI: 1.14, 1.56). CONCLUSION: RAASi discontinuation after hyperkalemia was associated with worsened mortality, which may underscore the benefits of continuing RAASi among patients with CKD.


Assuntos
Doenças Cardiovasculares , Hiperpotassemia , Insuficiência Renal Crônica , Adulto , Humanos , Idoso , Hiperpotassemia/induzido quimicamente , Hiperpotassemia/epidemiologia , Sistema Renina-Angiotensina , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Potássio , Insuficiência Renal Crônica/terapia , Anti-Hipertensivos/farmacologia , Aldosterona , Doenças Cardiovasculares/complicações
3.
Arch Phys Med Rehabil ; 104(9): 1474-1483, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37037292

RESUMO

OBJECTIVE: To estimate referent values for performance on clinical mobility tests conducted amongst racially diverse adults aged 50-95 years in the Southeast US. DESIGN: This is an observational study of community-dwelling older adults from diverse racial groups who participated in observational and rehabilitative studies conducted from 2011-2019. SETTING: Rehabilitation clinics around the greater metropolitan Atlanta, Georgia, region. PARTICIPANTS: A total of 314 adults (N=314; 222 women). Individuals were predominantly Black (n=121) or White (n=164), with some participants from other racial groups (n=29). INTERVENTIONS: Clinical and demographic data were collected at individual visits for each participant. MAIN OUTCOME MEASURES: Four Square Step Test (FSST), timed Up and Go (TUG) test, dual TUG test, 6-minute walk test (6MWT), 30-second chair stand, and gait speed were all used as assessments in each cohort. RESULTS: Performance slowly declines with increasing age, with a sharp drop in the ninth decade for preferred forward, backward, and fast gait speed; backward gait cadence; 6MWT, TUG test, dual-task TUG-Cognitive, and the 360° turn test. Declines were also seen in the eighth and ninth decades in the FSST. Among White participants, there were significant overall differences across age groups except in the assessment variable, preferred gait cadence. For Black individuals, there were significant overall differences across age groups for backward gait speed, fast gait speed, TUG-Cognitive, dual task, 6MWT, FSST, and 30-second chair stand. CONCLUSIONS: These data enrich current referent values for brief, commonly used clinical tests in a diverse, older Southeast US cohort. These data include representatives of the oldest old cohort. This study will support race- and age-specific fall prevention and mobility-enhancing therapeutic application among older patients in clinical practice.


Assuntos
Caminhada , Brancos , Idoso de 80 Anos ou mais , Humanos , Feminino , Idoso , Marcha , Velocidade de Caminhada , Vida Independente
4.
HIV Med ; 23 Suppl 1: 32-41, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35293109

RESUMO

OBJECTIVES: We aimed to analyze the incidence rates of new-onset diabetes, hypertriglyceridemia, hypercholesterolemia, liver injury, and renal injury during antiretroviral therapy (ART) among people living with HIV (PLWH) and determine the associated risk factors. METHODS: This study included PLWH enrolled from Beijing Ditan Hospital from November 11, 2004, to December 29, 2018. The incidence rates of new-onset diabetes, hypertriglyceridemia, hypercholesterolemia, liver injury, and renal injury were calculated and stratified based on ART regimen, CD4 count, and HIV-RNA. Risk factors were determined using Cox regression analysis. RESULTS: Overall, 6747 participants were included. Moreover, 4.5%, 43.3%, 25.4%, 11.2%, and 6.2% of patients developed new-onset diabetes, hypertriglyceridemia, hypercholesterolemia, liver injury, and renal injury, respectively, with incidence rates of 1.7, 26.9, 10.2, 3.9, and 5.5 per 100 person-years, respectively. Longitudinally, the incidence rates and percentages of these outcomes were highest in the first year of ART. The percentage of dyslipidemia was significantly higher in protease inhibitor (PI)-based regimen than in non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimen. However, the percentage of liver injury was significantly higher in NNRTI-based regimen than in PI-based regimen. In multivariate Cox regression analysis, low CD4 count (<200 cells/µL, adjusted hazard ratio [aHR] = 1.34, 95% confidence interval [CI] 1.15-1.57) and high HIV-RNA (>105 copies/mL, aHR = 1.26, 95% CI 1.08-1.48) were risk factors for hypertriglyceridemia. CONCLUSIONS: Clinical outcomes, including new-onset diabetes, dyslipidemia, and liver and renal injuries, are common in PLWH. Regular glucose, lipid, liver, and renal function monitoring is required during ART, especially in high-risk patients.


Assuntos
Fármacos Anti-HIV , Dislipidemias , Infecções por HIV , Hipercolesterolemia , Hipertrigliceridemia , Fármacos Anti-HIV/efeitos adversos , Contagem de Linfócito CD4 , Dislipidemias/induzido quimicamente , Dislipidemias/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Hipercolesterolemia/tratamento farmacológico , Hipertrigliceridemia/induzido quimicamente , Hipertrigliceridemia/tratamento farmacológico , Hipertrigliceridemia/epidemiologia , RNA/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Carga Viral
5.
BMC Infect Dis ; 22(1): 4, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983408

RESUMO

BACKGROUND: We aimed to clarify the characteristics, risk factors, and prognosis of stroke among HAART-naive people living with HIV (PLWH) in China. METHODS: We selected HAART-naive PLWH admitted to Beijing Ditan Hospital, Capital Medical University, from 1 January 2009 to 31 December 2019. Demographic and clinical data were obtained by searching an anonymous electronic case system. Descriptive analysis and logistic regression and Cox proportional hazard models were used to determine the characteristics and predictors of stroke among all HAART-naive PLWH and evaluate the risk factors of mortality in HAART-naive PLWH with stroke. RESULTS: Stroke was diagnosed in 105 cases (3.7%) of 2867 HAART-naive PLWH. Multivariate logistic regression indicated that age of 30-55 years (OR 1.903, 95% CI 1.005-3.603, p = 0.048), age of ≥ 55 years (OR 4.104, 95% CI 1.928-8.737, p < 0.001), and CD4 count of < 200 cells/µL (OR 2.005, 95% CI 1.008-3.985, p = 0.047) were associated with increased odds of stroke. Diabetes (OR 3.268, 95% CI 1.744-6.125, p < 0.001), hypertension (OR 2.301, 95% CI 1.425-3.717, p = 0.001), syphilis (OR 2.003, 95% CI 1.300-3.089, p = 0.002), and complicated AIDS-defining CNS diseases (OR 7.719, 95% CI 4.348-13.703, p < 0.001) were risk factors for stroke. Of the 105 stroke patients, 12 (11.4%) died during hospitalisation, and the risk factors for mortality among patients with stroke were age of > 65 years (AHR: 8.783, 95% CI 1.522-50.668, p = 0.015), complicated severe pneumonia (AHR: 3.940, 95% CI 1.106-14.029, p = 0.034), and AIDS-defining CNS diseases (AHR: 19.766, 95% CI 3.586-108.961, p = 0.001). CONCLUSIONS: For HAART-naive people living with HIV (PLWH), stroke occurred in various age groups, and early screening for stroke, timely intervention for risk factors among patients in various age groups, and controlling the CD4 count are extremely important in reducing the burden of stroke.


Assuntos
Infecções por HIV , Acidente Vascular Cerebral , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , China/epidemiologia , HIV , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia
6.
Med Sci Monit ; 28: e937264, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36196026

RESUMO

BACKGROUND There are few studies of GeneXpert MTB/RIF (hereafter referred to as Xpert) detection technology in HIV-infected people in China. Therefore, this study aimed to evaluate the value of Xpert in HIV/TB co-infected patients and to provide reference and guidance for the diagnosis of TB in HIV-infected populations. MATERIAL AND METHODS This study reviewed medical records of human immunodeficiency virus (HIV) patients hospitalized at the Infection Center of Beijing Ditan Hospital affiliated to Capital Medical University from January 2018 to May 2020, and patients diagnosed with pulmonary and extrapulmonary tuberculosis were screened as study subjects. Sensitivity and specificity of Xpert were analyzed using ROC curves. RESULTS Of the 413 HIV patients, 177 patients met the entry criteria, of which the diagnosis was active pulmonary tuberculosis (PTB): 145 and extrapulmonary tuberculosis (EPTB): 32. The sensitivity of Xpert for PTB and EPTB was 82.0% and 100%, higher than that of acid-fast bacilli (AFB) (61.0% and 58.3%), and slightly lower than that of T-SPOT.TB (91.0% and 100%); the specificity was 83.7% and 93.5%, higher than that of AFB (72.6%, 87.1%) and T-SPOT.TB (16.6%, 21.2%). The sensitivity of Xpert was 100% in bronchoalveolar lavage fluid (BALF) and 80.0% in sputum; in patients with CD4⁺ <200 cells/mm³, the sensitivity of Xpert was 90.0% and specificity was 84.8%, higher than that of AFB (60.0%, 75.5%) and T-SPOT.TB (90.0%, 21.5%). CONCLUSIONS Xpert has a high accuracy in HIV/TB co-infected patients, and Xpert still shows a high sensitivity and specificity even in HIV patients with CD4⁺ <200 cells/mm³. Xpert is recommended for the diagnosis of tuberculosis in HIV-infected patients.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose Pulmonar , Tuberculose , Infecções por HIV/complicações , Humanos , Mycobacterium tuberculosis/genética , Estudos Retrospectivos , Rifampina , Sensibilidade e Especificidade , Escarro , Tuberculose/complicações , Tuberculose/diagnóstico , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/diagnóstico
7.
BMC Cardiovasc Disord ; 21(1): 438, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34525967

RESUMO

BACKGROUND: The risk factors of in-stent restenosis (ISR) among coronary artery disease (CAD) patients with syphilis after percutaneous coronary intervention (PCI) are not fully understood. Therefore, this study aimed to elucidate not only the risk factors of ISR among CAD patients with syphilis after performing PCI, but also the population attributable risk percentage (PAR%), which is used to quantify the proportion of ISR that could be eliminated if particular risk factors are not present. METHODS: Evaluation of the prevalence, risk factors, and their PAR% for ISR among CAD patients with syphilis undergoing PCI was conducted retrospectively at Beijing Ditan Hospital. CAD patients with syphilis underwent PCI from August 2010 to August 2019 and received a diagnosis, coronary angiography, PCI, and periodical follow-up. The clinical, laboratory, and imaging data were reviewed and summarised anonymously from electronic medical records. The chi-square or Fisher exact test was used in data analysis. RESULTS: Among 114 CAD patients with syphilis undergoing PCI, ISR occurred in 18 patients (15.78%). The multivariate Cox regression model indicated that average stent length ≥ 35 mm (adjusted hazard ratio [HR] = 4.47, 95% confidence interval [CI] = 1.30-15.44, p = 0.018) and titres of the toluidine red unheated serum test (TRUST) > 1:16 (adjusted HR = 3.72, 95% CI = 1.22-11.36, p = 0.021) were associated with an increased risk of ISR, while successful antisyphilitic treatment (adjusted HR = 0.12, 95% CI = 0.02-0.95, p = 0.045) was protective predictor of ISR among these patients. The PAR% values of particular risk factors associated with ISR including average stent length ≥ 35 mm, titres of TRUST > 1:16, and successful antisyphilitic treatment were 12.2%, 24.0%, and -39.6%, respectively, among these patients. CONCLUSIONS: Preventing the occurrence of ISR among CAD patients with syphilis undergoing PCI requires clinical intervention. Our results indicated that carefully evaluating the length of the vessel lesion to determine whether the stent length is < 35 mm, prioritising the clinical intervention for titres of TRUST > 1:16, and providing successful antisyphilitic treatment could reduce the risk of ISR occurrence.


Assuntos
Doença da Artéria Coronariana/terapia , Reestenose Coronária/epidemiologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Stents , Sífilis/epidemiologia , Pequim/epidemiologia , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/epidemiologia , Reestenose Coronária/diagnóstico por imagem , Reestenose Coronária/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Sífilis/diagnóstico , Sífilis/terapia , Fatores de Tempo , Resultado do Tratamento
8.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4704-4711, 2021 Sep.
Artigo em Zh | MEDLINE | ID: mdl-34581079

RESUMO

As the main chemical constituents, iridoids are widely distributed within Gentiana, Gentianaceae, with promising bioactivities. Based on the previous work, the transcriptome of G. lhassica, an original plant of Tibetan herb "Jieji Nabao", was sequenced and analyzed in this study, and the transcriptome databases of roots, stems, leaves, and flowers were constructed so as to explore unigenes that may encode the key enzymes in the biosynthetic pathway of iridoids. Then, qRT-PCR was used to validate the relative expression levels of 11 genes named AACT, DXS, MCS, HDS, IDI, GPPS, GES, G10H, 7-DLNGT, 7-DLGT, and SLS in roots, stems, leaves, and flowers. Also, the total contents of gentiopicroside and loganic acid were determined by HPLC, respectively. The results are as follows:(1)a total of 76 486 unigenes with an average length of 852 bp were obtained;(2)335 unigenes were involved in 19 stan-dard secondary metabolism pathways in KEGG database, with phenylpropanoid biosynthesis having the maximum number(75 unigenes), and no isoflavone biosynthetic pathway was annotated;(3)171 unigenes participatedin 27 key enzymes encoding in the biosynthetic pathway of iridoids, and 1-deoxy-D-xylulose-5-phosphate reductoisomerase(DXR) gene was highly expressed;(4)qRT-PCR results were approximately consistent with RNA-Seq data and the relative expression levels of the 11 genes were higher in the aboveground parts(stem, leaf, and flower) than in the underground part(root);(5)the total contents of gentiopicroside and loganic acid were higher in the aboveground parts(stem, leaf, and flower) than in the underground part(root), and the difference was significant. This study provides basic scientific data for accurate species identification, evaluation of germplasm resources, research on secondary pro-duct accumulation of medicinal plants within Gentianaceae, and protection of endangered alpine species.


Assuntos
Gentiana , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Gentiana/genética , Iridoides , Transcriptoma
9.
Chirality ; 31(9): 658-668, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31268190

RESUMO

An environmental and sensitive sample pretreatment method was established and combined with high-performance liquid chromatography (HPLC) for the analysis of tetracycline hydrochloride (TC) in feed water and lake water. One element small molecule alcohol-salt aqueous two-phase system (ATPS) cannot effectively adjust the polarity of the system, but binary small molecule alcohol-salt ATPS can adjust the polarity and improve the extraction efficiency of antibiotics. In this work, a binary ATPS based on ethanol +2-propanol + (NH4 )2 SO4 system was formed and applied to the separation and purification of TC in real water samples. The influence factors on partition behaviors of TC were discussed, including the types and the concentration of phase salts, the volume ratio of alcohol, the pH value, extraction temperature, and the standing time. The response surface methodology was used to determine the best experimental conditions for multi-factor experiments. Under this optimal condition, the extraction efficiency of TC reached 95.7%. This new method is considered to have significant application in the divorce of antibiotics.

10.
Food Technol Biotechnol ; 57(2): 260-271, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31537975

RESUMO

In this study, a novel type of multi-armed polymer (poyltehylene glycol, PEG) magnetic graphene oxide (GO) composite (GO@Fe3O4@6arm-PEG-NH2) has been synthesized as a support for immobilization of horseradish peroxidase (HRP) for the first time. The loading amount of HRP was relatively high (186.34 mg/g) due to the surface of carrier material containing a large amount of amino groups from 6arm-PEG-NH2, but degradation rate of phenols was also much higher (95.4%), which is attributed to the synergistic effect between the free HRP (45.4%) and the support material of GO@Fe3O4@6arm-PEG-NH2 (13.6%). Compared with the free enzyme, thermal, storage and operational stability of the immobilized HRP improved. The immobilized HRP still retained over 68.1% activity after being reused 8 times. These results suggest that the multi-armed magnetic composite has good application prospect for enzyme immobilization.

11.
Luminescence ; 33(1): 15-21, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28714253

RESUMO

A novel fluorescent probe-based naphthalene Schiff, 1-(C2-glucosyl-ylimino-methyl)-naphthalene-2-ol (L) was synthesized by coupling d-glucosamine hydrochloride with 2-hydroxy-1-naphthaldehyde. It exhibited excellent selectivity and highly sensitivity for Al3+ in ethanol with a strong fluorescence response, while other common metal ions such as Pb2+ , Mg2+ , Cu2+ , Co2+ , Ni2+ , Cd2+ , Fe2+ , Mn2+ , Hg2+ , Li+ , Na+ , K+ , Fe3+ , Cr3+ , Zn2+ , Ag+ , Ba2+ and Ca2+ did not cause the same fluorescence response. The probe selectively bound Al3+ with a binding constant (Ka ) of 5.748 × 103  M-1 and a lowest detection limit (LOD) of 4.08 nM. Moreover, the study found that the fluorescence of the L - Al3+ complex could be quenched after addition of F- in the same medium, while other anions, including Cl- , Br- , I- , NO2- , NO3- , ClO4- , CO32- , HCO3- , SO42- , HSO4- , CH3 COO- , PO43- , HPO42- , S2- and S2 O32- had nearly no influence on probe behaviour. Binding of the [L - Al3+ ] complex to a F- anion was established by different fluorescence titration studies, with a detection limit of 3.2 nM in ethanol. The fluorescent probe was also successfully applied in the imaging detection of Al3+ and F- in living cells.


Assuntos
Alumínio/análise , Corantes Fluorescentes/química , Fluoretos/análise , Naftalenos/química , Fluorescência , Corantes Fluorescentes/síntese química , Íons/análise , Estrutura Molecular , Naftalenos/síntese química , Espectrometria de Fluorescência
12.
Bioprocess Biosyst Eng ; 41(7): 1051-1060, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29654356

RESUMO

Magnetic double-shell hybrid microspheres (Fe3O4@SiO2@p(NIPAM-co-GMA)) have been developed as a promising supported substrate for the immobilization of cellulase. Since the surface of the magnetic microspheres not only contains an epoxy group from GMA (glycidyl methacrylate) that can covalently bind to the enzyme, but also has an intelligent temperature response property from NIPAM (N-isopropylacrylamide), the cellulase can be covalently bonded to the magnetic microspheres and have a temperature-sensitive capability. The immobilized cellulase has the recovery ability of cellulase activity after a high-temperature inactivation. The average amount and activity of immobilized enzymes, respectively, was 233 mg g-1, 57.4 U mg-1 under the optimized conditions. The experimental results show that the immobilized cellulase has a wider catalytic temperature range, better temperature and storage stability. The residual activity still remained about 65.6% of the initial activity after the sixth catalysis run, which indicated that the immobilized enzyme had high reproducibility.


Assuntos
Celulase/química , Enzimas Imobilizadas/química , Óxido Ferroso-Férrico/química , Campos Magnéticos , Microesferas , Dióxido de Silício/química , Acrilamidas/química , Estabilidade Enzimática , Compostos de Epóxi/química , Metacrilatos/química
13.
Mikrochim Acta ; 185(1): 48, 2017 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-29594547

RESUMO

A polymer imprinted with acrylamide (AM-MIP) was synthesized on the surface of graphene oxide by surface polymerization of propionamide (serving as a dummy template), methacrylic acid (as the functional monomer) and ethylene glycol dimethacrylate (the cross-linker). ZnS quantum dots (QDs) doped with Mn(II) ions were added to the AM-MIP to act as fluorescence source. The AM-MIP was characterized by infrared spectroscopy, scanning electron microscopy and X-ray powder diffraction, suggesting that the imprinted layer was successfully grafted onto graphene oxide. The fluorescence of the doped QDs is quenched when loading the AM-MIP with acrylamide (AM), and the quenching effect is much stronger than the non-imprinted polymer (AM-NIP). Quenching follows Stern-Volmer kinetics. The combination of imprinting and fluorometric detection offer AM-IIP capability to accumulate trace AM before direct determination, omitting desorption and separation or other methods. The excitation and emission spectra of AM-MIP peak at 325 nm and 601 nm, respectively. Under optimal conditions, fluorescence drops linearly in the 0.5-60 µmol·L-1 acrylamide concentration range, and the detection limit is 0.17 µmol·L-1. The method has been applied to the determination of AM in spiked water samples and gave recoveries in the range from 100.2 to 104.5%, with relative standard deviations in the 1.9 to 3.9% range. In our perception, the AM-MIP presented here is a promising fluorescent probe for the detection of trace acrylamide in food. Graphical abstract Schematic of the preparation of graphene oxide coated with a molecularly imprinted polymer doped with Mn(II)-doped ZnS quantum dots. Propionamide serves as a dummy template. Acrylamide acts as a quencher of fluorescence, and this effect is used for its selective fluorometric determination.

14.
Water Environ Res ; 89(3): 281-287, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28236822

RESUMO

With the enhancement of people's environmental consciousness, the treatment of wastewater was studied as the focus of this paper. Here we present a simple two-step extraction to realize efficient separation of fluorescent whitening agents VBL and cyclic utilization of surfactant to reduce the cost of wastewater treatment and environmental pollution. Firstly, the removal of VBL has been achieved by CPE using TX-114 as nonionic surfactant. The results showed that complete extraction was possible using 1% (w/w) TX-114 for VBL concentration not exceeding 17.5 mg/L, otherwise using a higher concentration of 1.5% (w/w) TX-114. Then the surfactant from the coacervate phase was recycled by changing the potential difference between phases. The morphology of micelles and solubilization mechanism of VBL were demonstrated through the observation of a fluorescent microscope. This method was successfully used to remove the VBL from wastewater sample and the surfactant could be reused several times.


Assuntos
Derivados de Benzeno/isolamento & purificação , Polietilenoglicóis/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/isolamento & purificação , Resíduos Industriais/prevenção & controle , Octoxinol , Reciclagem
15.
J Sep Sci ; 39(7): 1371-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26841822

RESUMO

A tailor-made Cu(II) ion-imprinted polymer based on large-surface-area graphene oxide sheets has been synthesized for the preconcentration and determination of trace copper from food samples by solid-phase extraction. Attributed to the ultrahigh surface area and hydrophilicity of graphene oxide, the Cu(II) ion-imprinted polymer prepared by the surface ion-imprinting technique exhibited a high binding capacity and a fast adsorption rate under the optimized experimental conditions. In the static adsorption experiments, the maximum adsorption capacity of Cu(II) ion-imprinted polymer is 109.38 mg/g at 25°C, which is much higher than that of the nonimprinted polymer (32.12 mg/g). Meanwhile, the adsorption is very rapid and equilibrium is reached after approximately 30 min. The adsorption mechanism is found to follow Langmuir adsorption model and the pseudo-second-order adsorption process. The Cu(II) ion-imprinted polymer was used for extracting and detecting Cu(II) in food samples combined with graphite flame atomic adsorption spectrometry with high recoveries in the range of 97.6-103.3%. The relative standard deviation and limit of detection of the method were evaluated as 1.2% and 0.37 µg/L, respectively. The results showed that the novel absorbent can be utilized as an effective material for the selective enrichment and determination of Cu(II) from food samples.


Assuntos
Cobre/análise , Cobre/isolamento & purificação , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Grafite/química , Óxidos/química , Polímeros/química , Adsorção , Análise de Alimentos/instrumentação , Concentração de Íons de Hidrogênio , Íons/análise , Impressão Molecular , Tamanho da Partícula , Extração em Fase Sólida , Propriedades de Superfície
16.
Yao Xue Xue Bao ; 51(5): 821-7, 2016 05.
Artigo em Zh | MEDLINE | ID: mdl-29878733

RESUMO

Located in the transition zone between the Qinghai-Tibet Plateau and the Loess Plateau, Gansu province is one of the distribution centers of Sect. Cruciata, Gentiana (Gentianaceae) in China. Six species in the section, G. crassicaulis, G. straminea, G. siphonantha, G. officinalis, G. dahurica and G . macrophylla, are native to Gansu. In this paper, samples of 6 species and Halenia elliptica (outgroup) were collected. Nuclear DNA ITS, chloroplast DNA matK, rbcL, rpoC1, trnL (UAA) intron, psbA-trnH, atpB-rbcL, trnS (GCU)-trnG (UCC), rpl20-rps12 and trnL (UAA)-trnF (GAA) were sequenced from these samples. Based on the sequence analyses, high intragenomic polymorphisms were detected in ITS regions of G. crassicaulis, G. straminea, G. siphonantha, G. officinalis and G. dahurica, and they showed incomplete concerted evolution. A methodological study to identifying such close-related species as G. macrophylla, G. officinalis and G. dahurica was carried out based on the special genotypes. The results showed that 7 cp DNA sequence fragments could be used to identify G. crassicaulis, G. straminea and G. siphonantha. With nr ITS genotype II,III and IV of G. dahurica, the species can be distinguished from the close-related G. officinalis using 12 cloned sequences in a sample (with statistical significance).The cp DNA sequences of G. macrophylla were classified into two genotypes, and with genotype II, the species can be distinguished from the close-related G. officinalis and G. dahurica using 6 test samples each(with statistical significance). Furthermore, DNA barcode sequences were determined for all 6 species in Gansu. Also, the studies provide some basic data for analyses of genetic diversity and identification of Gentiana species.


Assuntos
Código de Barras de DNA Taxonômico , Gentianaceae/classificação , China , DNA de Cloroplastos/genética , DNA de Plantas/genética , Variação Genética , Filogenia , Rubiaceae , Tibet
17.
Zhonghua Nan Ke Xue ; 22(7): 645-648, 2016 07.
Artigo em Zh | MEDLINE | ID: mdl-28965385

RESUMO

Objective: To investigate the clinical effect of Jujing No.2 Decoction on male infertility induced by varicocele. METHODS: We equally randomized 70 male patients with varicocele-induced infertility into a treatment group and a control group, the former treated with modified Jujing No.2 Decoction (1 dose a day, bid) and the latter given Danshen Tablets (4 tablets once, tid) plus Liu Wei Di Huang Wan (8 pills once, tid), both for 3 months. We examined the spermatic veins of the patients by ultrasonography and performed seminal analysis before and after medication. RESULTS: Compared with the controls, the patients in the treatment group showed significant improvement after medication in sperm concentration (ï¼»12.35±2.12ï¼½ vs ï¼»18.56±4.16ï¼½ ×106/ml, P<0.05), progressively motile sperm (ï¼»16.18±6.34ï¼½ vs ï¼»24.63±8.51ï¼½ %, P<0.05), and morphologically normal sperm (ï¼»11.59±5.31ï¼½ vs ï¼»14.17±6.02ï¼½ %, P<0.05). In the control group, sperm concentration was increased from (12.29±2.07) ×106/ml at the baseline to (13.13±3.13) ×106/ml after medication, progressively motile sperm from (16.13±6.45) % to (20.55±7.30) % (P<0.05), and morphologically normal sperm from (11.62±5.35) % to (12.69±5.77) %. The total effectiveness rate was significantly higher in the treatment than in the control group (71.88% vs 46.67%, P<0.05). The inner diameter of the left spermatic vein was decreased from (0.32±0.05) mm at the baseline to ï¼»0.26±0.05ï¼½ mm after medication in the treatment group (P<0.05) and from (0.32±0.03) mm to (0.29±0.04) mm in the control (P<0.05), with statistically significant difference between the two groups after medication (P<0.05). CONCLUSIONS: Jujing No.2 Decoction is effective in the treatment of varicocele-induced male infertility.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Infertilidade Masculina/tratamento farmacológico , Varicocele/tratamento farmacológico , Humanos , Infertilidade Masculina/etiologia , Masculino , Salvia miltiorrhiza , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Cordão Espermático/diagnóstico por imagem , Varicocele/complicações , Veias/diagnóstico por imagem
18.
Langmuir ; 31(32): 8841-51, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26204060

RESUMO

In the present work, a novel two-dimensional (2D) nickel ion-imprinted polymer (RAFT-IIP) has been successfully synthesized based on the graphene oxide/SiO2 composite by reversible addition-fragmentation chain-transfer (RAFT) polymerization. The imprinted materials obtained are characterized by Fourier transmission infrared spectrometry (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The results show that the thermal stability of the graphene oxide/SiO2 composite is obviously higher than that of graphene oxide. RAFT-IIP possesses an excellent 2D homogeneous imprinted polymer layer, which is a well-preserved unique structure of graphene oxide/SiO2. Owing to the intrinsic advantages of RAFT polymerization and 2D imprinted material, RAFT-IIP demonstrate a superior specific adsorption capacity (81.73 mg/g) and faster adsorption kinetics (30 min) for Ni(II) in comparison to the ion-imprinted polymer prepared by traditional radical polymerization and based on the common carbon material. Furthermore, the adsorption isotherm and selectivity toward Ni(II) onto RAFT-IIP and nonimprinted polymer (NIP) are investigated, indicating that RAFT-IIP has splendid recognizing ability and a nearly 3 times larger adsorption capacity than that of NIP (30.94 mg/g). Moreover, a three-level Box-Behnken experimental design with three factors combining the response surface method is utilized to optimize the desorption process. The optimal conditions for the desorption of Ni(II) from RAFT-IIP are as follows: an HCl-type eluent, an eluent concentration of 2.0 mol/L, and an eluent volume of 10 mL.


Assuntos
Grafite/química , Impressão Molecular , Níquel/química , Óxidos/química , Polímeros/síntese química , Dióxido de Silício/química , Adsorção , Íons/química , Tamanho da Partícula , Polímeros/química , Propriedades de Superfície
19.
Zhongguo Zhong Yao Za Zhi ; 40(23): 4680-5, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-27141683

RESUMO

The alpine plant Gentiana robusta is an endemic species to the Sino-Himalayan subregion. Also, it is one of the original plants used as traditional Tibetan medicine Jie-Ji. We sequence the nuclear ribosomal internal transcribed spacer (ITS) regions, matK, rbcL, rpoC1, trnL (UAA), psbA-trnH, atpB-rbcL, trnS( GCU)-trnG(UCC), rpl20-rps12, trnL(UAA)-trnF( GAA) fragments of cp DNA in both G. robusta and such relative species as G. straminea, G. crassicaulis and G. waltonii. With Halenia elliptica as the outgroup, molecular systematic analysis reveals that G. robusta is a natural hybrid. G. straminea is the mother of hybrids, but the father is not very clear. In addition, the molecular markers for distinguishing G. robusta from the parental species or closely related species are identified, respectively. Our studies may provide valuable reference for the species identifications of medicinal plants with complex genetic backgrounds.


Assuntos
DNA de Plantas/genética , Gentiana/classificação , Plantas Medicinais/classificação , Código de Barras de DNA Taxonômico , Gentiana/genética , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/genética , Plantas Medicinais/genética
20.
Zhong Yao Cai ; 38(8): 1571-5, 2015 Aug.
Artigo em Zh | MEDLINE | ID: mdl-26983226

RESUMO

OBJECTIVE: To study the embryonic development of Gentiana straminea, G. robusta, G. crassicaulis and G. tibetica. METHODS: The seed germination rates, length and width of embryos, starch grains and chloroplasts were observed and analyzed by statistic software. RESULTS: The seed germination rates of the four species were all high. The increase of the length of embryo depended mainly on the increase of the length of hypocotyl. Starch grains were stored in cells and chloroplasts appeared in cotyledons. The process of germination was divided into eight periods. CONCLUSION: The embryo growth characteristics of the four species are recognized, and the results can be used to study the in situ conservation, genetic breeding and cultivation of Sect. Cruciata.


Assuntos
Gentiana/embriologia , Germinação , Plantas Medicinais/embriologia , Gentiana/classificação , Gentiana/crescimento & desenvolvimento , Plantas Medicinais/classificação , Plantas Medicinais/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento
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