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1.
Chemosphere ; : 142915, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39038712

RESUMO

Iodinated X-ray contrast media (ICM) was frequently detected in the aqueous environment. In this work, the applicability of three graphene-based nanomaterials (graphene nanosheets (GNS), graphene oxide (GO), and reduced graphene oxide (rGO)) for the adsorptive removal of the six ICMs including iohexol, iopamidol, iomeprol, iopromide, iodixanol and ioversol from aqueous solution was firstly evaluated by batch adsorption method. Among the three graphene-based nanomaterials, the GNS displayed the best adsorption performances for the adsorption of the six ICMs. The maximum uptakes of the six ICMs by the GNS (161.5 mg g-1 for iohexol, 267.2 mg g-1 for iodixanol, 197.7 mg g-1 for iopromide, 197.0 mg g-1 for iopamidol, 109.6 mg g-1 for iomeprol, and 168.2 mg g-1 for ioversol) can rapidly achieved within 10 min and indicate no dependence on pH in the range of 4-9. The results obtained from the calculations of isotherms, kinetics and thermodynamic supported the occurrence of a chemisorption of the GNS for the six ICMs. The π-π interactions between benzene ring of the ICMs and the sp2-hybridized two-dimensional sheet of GNS were deemed the predominant adsorption mechanism.

2.
Open Life Sci ; 18(1): 20220638, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37483425

RESUMO

The purpose of this study was to ascertain the fresh processing technology of Cut Ophiopogonis Radix using a multi-index evaluation. This study comprehensively evaluated the fresh processing technology of sliced Cut Ophiopogonis Radix by investigating the cutting methods, cutting thickness, and drying conditions, and referring to The Chinese Pharmacopoeia 2020 edition. The appearance traits, internal quality (extract, total saponins, total flavonoids, total polysaccharides), and drying efficiency were used as evaluation indexes. The physical attributes of Cut Ophiopogonis Radix were found to vary based on the processing techniques employed. The shape, surface characteristics, texture, and color were observed to differ across the different methods. Notably, the apparent quality of Cut Ophiopogonis Radix was superior in samples processed using A1B1C1, A1B2C2, and A3B1C3 techniques. Drying time and energy consumption of Cut Ophiopogonis Radix produced by the A1B2C2 and A2B1C2 processes were less than those of other treatments, making them the optimal process for fresh processing Cut Ophiopogonis Radix. The impact of the cutting method and thickness on the extract was found to be statistically insignificant (P > 0.05). However, the drying method was observed to have a significant impact on the extract (P < 0.05). The cutting method, Cut thickness, and drying method did not affect the total saponin content (P > 0.05), but they had significant effects on the total polysaccharide and flavonoid contents (P < 0.01). Total polysaccharides were most affected by the cutting method, while total flavonoids were most affected by the drying condition. Based on the characteristics and internal quality, the fresh processing technology for Cut Ophiopogonis Radix was determined: fresh Ophiopogonis Radix was sliced to a thickness of 2-4 mm and dried at 55°C or a low temperature. The feasibility of Cut Ophiopogonis Radix is improved through its fresh processing. According to the evaluation indices, it is recommended to utilize the novel processing technique involving "fresh Ophiopogonis Radix" with fresh cuts, a cut thickness ranging from 2 to 4 mm, and drying at a temperature of 55℃ or through low-temperature drying. The Cut Ophiopogonis Radix exhibited favorable appearance and internal characteristics, thereby furnishing a scientific basis and innovative insights for the production of ophiopogon decoction slices.

3.
Opt Lett ; 48(3): 558-561, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36723530

RESUMO

A simple expression for the correlations of beams radiated by Schell-model sources carrying a prescribed astigmatic phase (cross phase) in 3D space is derived. The z-coherence of such sources upon free-space propagation is investigated in detail. It is demonstrated that the z-coherence does not decrease to zero with an increasing separation of two axial points. Our results show that the initial cross phase, coherence, and correlation state of such sources affect the distribution of the z-coherence. Furthermore, the cross phase plays a role in maintaining z-coherence, which will be useful in applications where high z-coherence is required.

4.
Biomed Chromatogr ; 37(1): e5526, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36250730

RESUMO

Because of the immense difficulty in identifying Cyathulae Capitatae Radix adulteration in Cyathulae Radix, this research aims at fortifying the quality control of Cyathulae Radix and its decoction pieces to guarantee the effectiveness and safety of its clinical use in terms of source material. A method was devised to identify Cyathulae Capitatae Radix adulteration in Cyathulae Radix and its decoction pieces. This research takes achybidensaponin I, that is, the characteristic component of Cyathulae Capitatae Radix, as reference substance and adopts HPLC for detection. The results revealed that, among all samples collected, no trace of achybidensaponin I was found in the 21 batches of Cyathulae Radix, whereas achybidensaponin I was found in all the 14 batches of Cyathulae Capitatae Radix. The research sets 5% as the adulteration limit, that is, 1.45 mg/g Cyathulae Capitatae Radix was detected in 57.14% of the 49 batches of market samples collected and the ratio was 51.02% in the case of 5% adulteration limit. The method is not only precise and reliable but can also be used as a supplement for provisions regarding quality control of Cyathulae Radix and its decoction pieces in Pharmacopoeia of the People's Republic of China, to effectively crack down on Cyathulae Capitatae Radix adulteration in the market.


Assuntos
Medicamentos de Ervas Chinesas , Humanos , Raízes de Plantas , Controle de Qualidade , Cromatografia Líquida de Alta Pressão , Contaminação de Medicamentos
5.
J Phys Chem B ; 125(32): 9333-9340, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34355901

RESUMO

The central role of Coulombic interactions in enzyme catalysis has inspired multiple approaches to sculpting electrostatic potential fields (EPFs) for controlling chemical reactivity, including ion gradients in water microdroplets, the tips of STMs, and precisely engineered crystals. These are powerful tools because EPFs can affect all reactions, even those whose mechanisms do not involve formal charges. For some time now, supramolecular chemists have become increasingly proficient in using encapsulation to control stoichiometric and catalytic reactions. However, the field has not taken advantage of the broad range of nanocontainers available to systematically explore how EPFs can affect reactions within their inner-spaces. With that idea in mind, previously, we reported on how positively and negatively charged supramolecular capsules can modulate the acidity and reactivity of thiol guests bound within their inner, yoctoliter spaces (Cai, X.; Kataria, R.; Gibb, B. C. J. Am. Chem. Soc. 2020, 142, 8291-8298; Wang, K.; Cai, X.; Yao, W.; Tang, D.; Kataria, R.; Ashbaugh, H. S.; Byers, L. D.; Gibb, B. C. J. Am. Chem. Soc. 2019, 141, 6740-6747). Building on this, we report here on the cyclization of 14-bromotetradecan-1-amine inside these yoctoliter containers. We examine the rate and activation thermodynamics of cyclization (Eyring analysis), both in the absence and presence of exogenous salts whose complementary ion can bind to the outside of the capsule and hence attenuate its EPF. We find the cyclization rates and activation thermodynamics in the two capsules to be similar, but that for either capsule attenuation of the EPF slows the reaction down considerably. We conclude the capsules behave in a manner akin to covalently attached electron donating/withdrawing groups in a substrate, with each capsule enforcing their own deviations from the idealized SN2 mechanism by moving electron density and charge in the activated complex and TS, and that the idealized SN2 mechanism inside the theoretical neutral host is relatively difficult because of the lack of solvation of the TS.


Assuntos
Aminas , Elétrons , Catálise , Eletricidade Estática , Termodinâmica
6.
Angew Chem Int Ed Engl ; 60(28): 15405-15411, 2021 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-33856080

RESUMO

The weak thermal polarization of nuclear spins limits the sensitivity of MRI, even for MR-sensitive nuclei as fluorine-19. Therefore, despite being the source of inspiration for the development of background-free MRI for various applications, including for multiplexed imaging, the inability to map very low concentrations of targets using 19 F-MRI raises the need to further enhance this platform's capabilities. Here, we employ the principles of CEST-MRI in 19 F-MRI to obtain a 900-fold signal amplification of a biocompatible fluorinated agent, which can be presented in a "multicolor" fashion. Capitalizing on the dynamic interactions in host-guest supramolecular assemblies in an approach termed GEST, we demonstrate that an inhalable fluorinated anesthetic can be used as a single 19 F-probe for the concurrent detection of micromolar levels of two targets, with potential in vivo translatability. Further extending GEST with new designs could expand the applicability of 19 F-MRI to the mapping of targets that have so-far remained non-detectable.


Assuntos
Meios de Contraste/análise , Imagem por Ressonância Magnética de Flúor-19 , Meios de Contraste/síntese química , Halogenação , Estrutura Molecular
7.
J Cancer ; 11(23): 6834-6840, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33123274

RESUMO

Purpose: To investigate the accuracy and the discriminatory performance in the prognostic prediction in breast cancer (BC) patients with ipsilateral supraclavicular lymph node (ISLN) metastasis using the between the American Joint Committee on Cancer (AJCC) 7th and 8th edition staging system. Methods: Female patients diagnosed as BC were retrieved from the Surveillance, Epidemiology, and End Results database between 2010 and 2014. Chi-squared test, Kaplan-Meier method, Cox proportional hazard analysis, and the receiver operating characteristics were used to conduct statistical analysis. Results: We included 1097 BC patients with ISLN metastasis (N3c disease), including 29.4% (n=322) and 70.6% (n=775) of patients with non-metastatic and metastatic stage at diagnosis, respectively. In non-metastatic stage patients, 64.9% of the patients categorized as having stage IIIC disease in the 7th edition AJCC staging system were downstaged to stage IIIA or IIIB according to the 8th AJCC staging criteria. The AJCC 8th edition staging system had better discriminatory prognostic value than the 7th AJCC staging (area under the curve: 0.586 vs. 0.577, P=0.0006), with a 5-year breast cancer-specific survival (BCSS) rate of 71.3%, 62.2%, 45.2% and 39.1% in stage IIIA, IIIB, IIIC, and IV cohorts, respectively (P<0.0001). The multivariate prognostic analysis revealed that the AJCC 8th edition staging system was an independent prognostic factor for BCSS, while no statistical difference in BCSS was found between the 8th AJCC stage IIIC and IV patients (P=0.188). Conclusion: The AJCC 8th edition pathological prognostic staging showed a better discriminatory prognostic value in ISLN-metastasized breast cancer patients. An additional clarification strategy in stage IIIC disease based on the 8th AJCC staging should be developed to differentiate patients who are curable with multimodality therapy and patients who have less benefit from curative treatment.

8.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 32(5): 570-574, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32576349

RESUMO

OBJECTIVE: To evaluate the prognostic value of plasma microRNA-30b-5p (miR-30b-5p) combined with extravascular lung water index (EVLWI) in patients with acute respiratory distress syndrome (ARDS). METHODS: 120 ARDS patients admitted to Danzhou People's Hospital from January 2016 to June 2019 were enrolled. The gender, age, body mass index (BMI), underlying diseases, etiology and baseline values of heart rate (HR), respiratory rate (RR), oxygenation index (OI), arterial partial pressure of carbon dioxide (PaCO2) and acute physiology and chronic health evaluation II (APACHE II) score were collected. According to the survival outcome during hospitalization, the patients were divided into survival group and death group. According to OI, the patients were divided into mild-moderate group (OI > 100 mmHg, 1 mmHg = 0.133 kPa) and severe group (OI ≤ 100 mmHg). The expression of plasma miR-30b-5p was detected by real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-PCR), and EVLWI was measured. The receiver operating characteristic (ROC) curve was drawn to analyze the value of plasma miR-30b-5p and EVLWI in predicting the death of patients with ARDS. Pearson correlation method was used to analyze the correlation between miR-30b-5p and EVLWI in ARDS patients with different prognosis during hospitalization. RESULTS: 120 patients with ARDS were enrolled in the analysis, with 42 patients in the death group, and 78 in the survival group; with 67 patients in the mild-moderate group, and 53 in the severe group. APACHE II score in the death group was higher than that in the survival group, but there was no significant difference in gender, age, BMI, underlying diseases, etiology or baseline values of HR, RR, OI, or PaCO2 between the two groups. The expression of plasma miR-30b-5p and EVLWI level in the death group were significantly higher than those in the survival group [miR-30b-5p (2-ΔΔCt): 2.28±0.74 vs. 0.52±0.06, EVLWI (mL/kg): 15.38±4.60 vs. 10.24±2.15,both P < 0.01]. The expression of plasma miR-30b-5p, EVLWI and mortality during hospitalization in the severe group were significantly higher than those in the mild-moderate group [miR-30b-5p (2-ΔΔCt): 2.05±0.65 vs. 0.93±0.17, EVLWI (mL/kg): 14.65±4.20 vs. 11.36±2.28, mortality during hospitalization: 58.5% (31/53) vs. 16.4% (11/67), all P < 0.01]. ROC curve analysis showed that the best cut-off value of plasma miR-30b-5p and EVLWI in predicting the death during hospitalization of ARDS patients were 1.62 and 13.28 mL/kg, respectively. Moreover, the area under ROC curve (AUC) of the combination of two parameters was significantly higher than that of the two alone (0.897 vs. 0.827, 0.785), with high sensitivity and specificity, 90.5% and 84.2%, respectively. Pearson correlation analysis showed that plasma miR-30b-5p in dead ARDS patients was significantly positively correlated with EVLWI (r = 0.768, P < 0.01), but the correlation was not found in surviving patients (r = 0.118, P > 0.05). CONCLUSIONS: The expression of plasma miR-30b-5p and EVLWI are related to the severity and prognosis of patients with ARDS, and the combination of the two has certain evaluation value for the prognosis of ARDS patients.


Assuntos
Síndrome do Desconforto Respiratório , APACHE , Água Extravascular Pulmonar , Humanos , MicroRNAs , Prognóstico , Curva ROC , Síndrome do Desconforto Respiratório/complicações , Síndrome do Desconforto Respiratório/genética
9.
J Am Chem Soc ; 142(18): 8291-8298, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32271561

RESUMO

Despite decades of research, there are still many open questions surrounding the mechanisms by which enzymes catalyze reactions. Understanding all the noncovalent forces involved has the potential to allow de novo catalysis design, and as a step toward this, understanding how to control the charge state of ionizable groups represents a powerful yet straightforward approach to probing complex systems. Here we utilize supramolecular capsules assembled via the hydrophobic effect to encapsulate guests and control their acidity. We find that the greatest influence on the acidity of bound guests is the location of the acidic group within the yoctoliter space. However, the nature of the electrostatic field generated by the (remote) charged solubilizing groups also plays a significant role in acidity, as does counterion complexation to the outer surfaces of the capsules. Taken together, these results suggest new ways by which to affect reactions in confined spaces.

10.
J Am Chem Soc ; 141(16): 6740-6747, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-30929421

RESUMO

The intrinsic structural complexity of proteins makes it hard to identify the contributions of each noncovalent interaction behind the remarkable rate accelerations of enzymes. Coulombic forces are evidently primary, but despite developments in artificial nanoreactor design, a picture of the extent to which these can contribute has not been forthcoming. Here we report on two supramolecular capsules that possess structurally identical inner-spaces that differ in the electrostatic potential (EP) field that envelops them: one positive and one negative. This architecture means that only changes in the EP field influence the chemical properties of encapsulated species. We quantify these influences via acidity and rates of cyclization measurements for encapsulated guests, and we confirm the primary role of Coulombic forces with a simple mathematical model approximating the capsules as Born spheres within a continuum dielectric. These results reveal the reaction rate accelerations possible under Coulombic control and highlight important design criteria for nanoreactors.

11.
J Int Med Res ; 46(9): 3824-3836, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30091401

RESUMO

Objective To enhance theoretical support of pyogenic liver abscess (PLA) treatment by comparing characteristics of patients with either PLA with an identified infectious origin (non-cryptogenic) or PLA with no obvious underlying cause (cryptogenic). Methods This retrospective study included all first episodes of PLA in adults admitted to a tertiary hospital between 2009 and 2016. Relevant clinical data were collected for patients with cryptogenic or non-cryptogenic PLA and compared across a number of characteristics. Results In all, 178 patients were included: 111 cases (62.4%) of cryptogenic PLA, and 67 cases (37.6%) of non-cryptogenic PLA. Diabetes mellitus was significantly more prevalent in patients with cryptogenic PLA than those with non-cryptogenic PLA. The proportion of multidrug resistance/poly-microbial infection was significantly lower and Klebsiella pneumoniae infection was significantly higher in the cryptogenic versus non-cryptogenic PLA group. Metastatic infection occurred in four patients with cryptogenic PLA only, and all had diabetes and K. pneumoniae infection. Multivariate logistic regression analysis revealed that male sex, diabetes and K. pneumoniae were independent predictors for cryptogenic PLA. Conclusions Cryptogenic and non-cryptogenic PLA have distinctly different characteristics, suggesting a potential need for different treatment approaches.


Assuntos
Abscesso Hepático Piogênico/diagnóstico , Adulto , Idoso , China , Complicações do Diabetes/complicações , Complicações do Diabetes/fisiopatologia , Farmacorresistência Bacteriana Múltipla/fisiologia , Feminino , Humanos , Abscesso Hepático/diagnóstico , Abscesso Hepático/etiologia , Abscesso Hepático/fisiopatologia , Abscesso Hepático Piogênico/complicações , Abscesso Hepático Piogênico/microbiologia , Abscesso Hepático Piogênico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
12.
Sci Transl Med ; 9(412)2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-29046433

RESUMO

Influenza B virus causes considerable disease burden worldwide annually, highlighting the limitations of current influenza vaccines and antiviral drugs. In recent years, broadly neutralizing antibodies (bnAbs) against hemagglutinin (HA) have emerged as a new approach for combating influenza. We describe the generation and characterization of a chimeric monoclonal antibody, C12G6, that cross-neutralizes representative viruses spanning the 76 years of influenza B antigenic evolution since 1940, including viruses belonging to the Yamagata, Victoria, and earlier lineages. Notably, C12G6 exhibits broad cross-lineage hemagglutination inhibition activity against influenza B viruses and has higher potency and breadth of neutralization when compared to four previously reported influenza B bnAbs. In vivo, C12G6 confers stronger cross-protection against Yamagata and Victoria lineages of influenza B viruses in mice and ferrets than other bnAbs or the anti-influenza drug oseltamivir and has an additive antiviral effect when administered in combination with oseltamivir. Epitope mapping indicated that C12G6 targets a conserved epitope that overlaps with the receptor binding site in the HA region of influenza B virus, indicating why it neutralizes virus so potently. Mechanistic analyses revealed that C12G6 inhibits influenza B viruses via multiple mechanisms, including preventing viral entry, egress, and HA-mediated membrane fusion and triggering antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity responses. C12G6 is therefore a promising candidate for the development of prophylactics or therapeutics against influenza B infection and may inform the design of a truly universal influenza vaccine.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Proteção Cruzada/imunologia , Vírus da Influenza B/imunologia , Receptores Virais/metabolismo , Animais , Anticorpos Neutralizantes/uso terapêutico , Sítios de Ligação , Cães , Quimioterapia Combinada , Mapeamento de Epitopos , Epitopos/imunologia , Feminino , Furões , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Imunização , Vírus da Influenza B/isolamento & purificação , Células Madin Darby de Rim Canino , Camundongos Endogâmicos BALB C , Modelos Moleculares , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/virologia , Oseltamivir/uso terapêutico , Domínios Proteicos , Resultado do Tratamento
13.
Zhong Yao Cai ; 39(6): 1247-50, 2016 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-30156794

RESUMO

Objective: To study the relationship between the component content of curcuminoids in Curcumae Longae Rhizoma and powder color indeces L*, a* and b* those were measured by chromaticity instrument, in order to provide scientific basis for quality assessment of Curcuma longa medicinal materials. Methods: Detect the content of curcumin,demethoxycurcumin,bisdemethoxycurcumin,then detect the content of curcuminoids by the Chinese Pharmacopoeia method. Measure the color indeces L*, a* and b* of Curcumae Longae Rhizoma powder by colorimeter. Finally, the relationship between the content and the color was analyzed by using the Grey Relational Analysis, Pearson correlation coefficient and regression analysis. Results: There was positive correlation between the content of curcuminoids and a*. But there was no definitely relation between the content of curcuminoids and b* or L*. Conclusion: The content of curcuminoids is closely related with the degree of the color red, the higher the content, the red is deeper. a* could be recognized as an important basis of Curcumae Longae Rhizoma medicinal materials quality.


Assuntos
Rizoma , Cor , Colorimetria , Curcuma , Curcumina/análogos & derivados , Diarileptanoides , Pós
14.
Zhongguo Zhong Yao Za Zhi ; 40(20): 4022-5, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-27062821

RESUMO

This research is to establish an HPLC method for the simultaneous determination of ophiopogonin D, ophiopogonin D', ophiopogonin C, deacetylophiopojaponin A and ophiogenin-3-O-α-L-rhamnosyl-(1-->2)-ß-D-glucoside in Ophiopogonis Radix. HPLC-ELSD analysis was performed on a Kromasil 100-5 C18 column (4.6 mm x 250 mm, 5 µm), with the mobile phase of acetonitrile (A) -water (B) in gradient elution mode (0-45 min, 35%-55% A), at a flow rate of 1 mL · min⁻¹. The column temperature was 35 °C and the drift tube temperature was 100 °C in a gas flow rate of 3.0 L · min⁻¹. The result showed that baseline of all the 5 constituents was well separated, and every constituent had wide linearity range and good linear relation (r > 0.999). The recovery rate was between 95.75% and 103.1%. The new established method for simultaneous determination of saponin constituents in Ophiopogonis Radix was sensitive and has good, repeatability. It could be applied to quality evaluation of Ophiopogonis Radix.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Ophiopogon/química , Saponinas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Raízes de Plantas/química , Saponinas/isolamento & purificação
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