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Theoretical insights into influence of additives on sulfamethoxazole crystal growth kinetics and mechanisms

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1503-1515 doi: 10.1007/s11705-022-2294-4

摘要: In this work, the influence of the initial chemical potential gradient, stirring speed, and polymer type on sulfamethoxazole (SMX) crystal growth kinetics was systematically investigated through density functional theory (DFT) calculations, experimental measurements and the two-step chemical potential gradient model. To investigate the influence of different conditions on the thermodynamic driving force of SMX crystal growth, SMX solubilities in different polymer solutions were studied. Four model polymers effectively improved SMX solubility. It was further found that polyvinylpyrrolidone (PVP) and hydroxypropyl methyl cellulose (HPMC) played a crucial role in inhibiting SMX crystal growth. However, polyethylene glycol (PEG) promoted SMX crystal growth. The effect of the polymer on the crystal growth mechanisms of SMX was further analyzed by the two-step chemical potential gradient model. In the system containing PEG 6000, crystal growth is dominated by the surface reaction. However, in the system containing PEG 20000, crystal growth is dominated by both the surface reaction and diffusion. In addition, DFT calculations results showed that HPMC and PVP could form strong and stable binding energies with SMX, indicating that PVP and HPMC had the potential ability to inhibit SMX crystal growth.

关键词: insoluble drugs     polymer     inhibition crystallization     crystal growth kinetics     DFT calculations    

Chronic inhibition of cyclic guanosine monophosphate-specific phosphodiesterase 5 prevented cardiac fibrosisthrough inhibition of transforming growth factor β-induced Smad signaling

null

《医学前沿(英文)》 2014年 第8卷 第4期   页码 445-455 doi: 10.1007/s11684-014-0378-3

摘要:

Recent evidences suggested that cyclic guanosine monophosphate-specific phosphodiesterase 5 (PDE5) inhibitor represents an important therapeutic target for cardiovascular diseases. Whether and how it ameliorates cardiac fibrosis, a major cause of diastolic dysfunction and heart failure, is unknown. The purpose of this study was to investigate the effects of PDE5 inhibitor on cardiac fibrosis. We assessed cardiac fibrosis and pathology in mice subjected to transverse aortic constriction (TAC). Oral sildenafil, a PDE5 inhibitor, was administered in the therapy group. In control mice, 4 weeks of TAC induced significant cardiac dysfunction, cardiac fibrosis, and cardiac fibroblast activation (proliferation and transformation to myofibroblasts). Sildenafil treatment markedly prevented TAC-induced cardiac dysfunction, cardiac fibrosis and cardiac fibroblast activation but did not block TAC-induced transforming growth factor-β1 (TGF-β1) production and phosphorylation of Smad2/3. In isolated cardiac fibroblasts, sildenafil blocked TGF-β1-induced cardiac fibroblast transformation, proliferation and collagen synthesis. Furthermore, we found that sildenafil induced phosphorylated cAMP response element binding protein (CREB) and reduced CREB-binding protein 1 (CBP1) recruitment to Smad transcriptional complexes. PDE5 inhibition prevents cardiac fibrosis by reducing CBP1 recruitment to Smad transcriptional complexes through CREB activation in cardiac fibroblasts.

关键词: PDE5     cardiac fibrosis     TGF-β     CREB    

Progress in membrane distillation crystallization: Process models, crystallization control and innovative

Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He

《化学科学与工程前沿(英文)》 2017年 第11卷 第4期   页码 647-662 doi: 10.1007/s11705-017-1649-8

摘要: Membrane distillation crystallization (MDC) is a promising hybrid separation process that has been applied to seawater desalination, brine treatment and wastewater recovery. In recent years, great progress has been made in MDC technologies including the promotion of nucleation and better control of crystallization and crystal size distribution. These advances are useful for the accurate control of the degree of supersaturation and for the control of the nucleation kinetic processes. This review focuses on the development of MDC process models and on crystallization control strategies. In addition, the most important innovative applications of MDC in the last five years in crystal engineering and pharmaceutical manufacturing are summarized.

关键词: membrane distillation crystallization     mathematics model     nucleation     separation     hybrid process    

Effects of a structurally related substance on the crystallization of paracetamol

Ali SALEEMI, I.I. ONYEMELUKWE, Zoltan NAGY

《化学科学与工程前沿(英文)》 2013年 第7卷 第1期   页码 79-87 doi: 10.1007/s11705-013-1308-7

摘要: Paracetamol (PCM) was crystallized from an isopropanol (IPA) solution containing various small amounts of metacetamol as an additive. The effect on the nucleation kinetics was studied by measuring the induction time to nucleation and the metastable zone width using focused beam reflectance measurements (FBRM) and attenuated total reflectance (ATR-UV/Vis) spectroscopy. Both the induction time and the metastable zone width were expressed as functions of the additive concentration. Small amounts of metacetamol (1–4 mol-%) were found to cause significant inhibition to the nucleation by extending both the induction time and the metastable zone width. A progressive change in the morphology of the paracetamol crystals from tabular to columnar habit was observed with increasing metacetamol concentration. The solvent also had a significant effect on the size of the paracetamol crystals as smaller crystals were obtained in IPA than in aqueous solution. The dissolution rate of paracetamol was improved by the incorporation of metacetamol with 4 mol-% having the most effect. A supersaturation control (SSC) approach was implemented for the PCM-IPA system with and without metacetamol in an attempt to control and obtain larger metacetamol-doped paracetamol crystals.

关键词: acetaminophen     metacetamol     crystallization     metastable zone width     induction time     supersaturation control    

Interfacial induction and regulation for microscale crystallization process: a critical review

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 838-853 doi: 10.1007/s11705-021-2129-8

摘要: Microscale crystallization is at the frontier of chemical engineering, material science, and biochemical research and is affected by many factors. The precise regulation and control of microscale crystal processes is still a major challenge. In the heterogeneous induced nucleation process, the chemical and micro/nanostructural characteristics of the interface play a dominant role. Ideal crystal products can be obtained by modifying the interface characteristics, which has been proven to be a promising strategy. This review illustrates the application of interface properties, including chemical characteristics (hydrophobicity and functional groups) and the morphology of micro/nanostructures (rough structure and cavities, pore shape and pore size, surface porosity, channels), in various microscale crystallization controls and process intensification. Finally, possible future research and development directions are outlined to emphasize the importance of interfacial crystallization control and regulation for crystal engineering.

关键词: interfacial crystallization     heterogeneous nucleation     supersaturation     micro/nanostructure     process control and intensification    

simultaneous anammox and denitrification system with short-term pyridine exposure: Process capability, inhibition

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1433-3

摘要:

• Short-term effect of the pyridine exposure on the SAD process was investigated.

关键词: Anammox     Inhibition     Metabolic pathway     Microbial community     Pyridine     SAD    

ROOT EXUDATES FROM CANOLA EXHIBIT BIOLOGICAL NITRIFICATION INHIBITION AND ARE EFFECTIVE IN INHIBITING

《农业科学与工程前沿(英文)》 2022年 第9卷 第2期   页码 177-186 doi: 10.15302/J-FASE-2021421

摘要:

A range of plant species produce root exudates that inhibit ammonia-oxidizing microorganisms. This biological nitrification inhibition (BNI) capacity can decrease N loss and increase N uptake from the rhizosphere. This study sought evidence for the existence and magnitude of BNI capacity in canola ( Brassica napus). Seedlings of three canola cultivars, Brachiaria humidicola(BNI positive) and wheat ( Triticum aestivum) were grown in a hydroponic system. Root exudates were collected and their inhibition of the ammonia oxidizing bacterium, Nitrosospira multiformis, was tested. Subsequent pot experiments were used to test the inhibition of native nitrifying communities in soil. Root exudates from canola significantly reduced nitrification rates of both N. multiformis cultures and native soil microbial communities. The level of nitrification inhibition across the three cultivars was similar to the well-studied high-BNI species B. humidicola. BNI capacity of canola may have implications for the N dynamics in farming systems and the N uptake efficiency of crops in rotational farming systems. By reducing nitrification rates canola crops may decrease N losses, increase plant N uptake and encourage microbial N immobilization and subsequently increase the pool of organic N that is available for mineralization during the following cereal crops.

关键词: ammonia oxidizing microorganisms / biological nitrification inhibition / farming rotations / nitrogen cycling / nitrogen use efficiency    

Inhibition character of crotonaldehyde manufacture wastewater on biological acidification

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1403-9

摘要:

• The inhibition of the main organic pollutions in CMW was demonstrated.

关键词: Crotonaldehyde manufacture wastewater     Biological acidification     Volatile fatty acids     Inhibition     Toxic units    

Roles of integrin β3 cytoplasmic tail in bidirectional signal transduction in a trans-dominant inhibition

null

《医学前沿(英文)》 2016年 第10卷 第3期   页码 311-319 doi: 10.1007/s11684-016-0460-0

摘要:

We evaluated the roles of calpain cleavage-related mutations of the integrin β3 cytoplasmic tail in integrin αIIbβ3 bidirectional signaling using a trans-dominant inhibition model. Chimeric Tac-β3 proteins (i.e., Tac-β3, Tac-β3D741, Tac-β3D747, Tac-β3D754, Tac-β3D759, and Tac-β3DNITY) consisting of the extracellular and transmembrane domains of human IL-2 receptor (Tac) and the human integrin β3 cytoplasmic domain were stably expressed in the 123 CHO cells harboring human glycoprotein Ib-IX and wild-type integrin αIIbβ3. The different cells were assayed for stable adhesion and spreading on immobilized fibrinogen, and for binding soluble fibrinogen representing outside-in and inside-out signaling events, respectively. The chimeric protein Tac-β3 inhibited, and Tac-β3DNITY partially attenuated stable adhesion and spreading. Tac-β3, Tac-β3D759, Tac-β3DNITY, and Tac-β3D754, but not Tac-β3D747 or Tac-β3D741, impaired the soluble fibrinogen binding. Results indicated that the bidirectional signaling was significantly inhibited by Tac-β3 and Tac-β3DNITY, albeit to a much lesser extent. Moreover, only inside-out signaling was impaired in the 123/Tac-β3D759 and 123/Tac-β3D754 cells in contrast to an intact bidirectional signaling in the 123/Tac-β3D747 and 123/Tac-β3D741 cells. In conclusion, the calpain cleavage of integrin β3 resulted in the regulatory effects on signaling by interrupting its interaction with cytoplasmic proteins rather than altering its conformation, and may thus regulate platelet function.

关键词: integrin β3     signal transduction     trans-dominant inhibition model    

The feasibility of coating by cooling crystallization on ibuprofen naked tablets

Fatima Mameri, Ouahiba Koutchoukali, Mohamed Bouhelassa, Anne Hartwig, Leila Nemdili, Joachim Ulrich

《化学科学与工程前沿(英文)》 2017年 第11卷 第2期   页码 211-219 doi: 10.1007/s11705-017-1619-1

摘要: Sugar spray coating is a frequently used process in the pharmaceutical industry. However, this process presents the disadvantage to form an amorphous coating around the active ingredient. A crystalline coating formed on the surface of a tablet is highly desirable. Recently, a new process of coating by cooling crystallization has been developed and applied on bisacodyl pastilles obtained by melt crystallization. In this work, we investigated the feasibility of coating by cooling crystallization on ibuprofen “naked tablets” manufactured by compression. In the first part of this work, the solubility and the metastable zone width have been determined experimentally for the coating solution because they are essential factors for any crystallization process. In the second part, the coating process is investigated on the operating conditions that affect the surface morphology and the crystal growth rate. These experimental conditions include concentration of the coating solution, degree of sub-cooling, agitation speed, retention time, and surface properties of the naked ibuprofen tablets. The results show that naked tablet coating by cooling crystallization is feasible and can be applied in the pharmaceutical industry.

关键词: coating     solution crystallization     ibuprofen tablets     sucrose    

Head-to-tail cyclization of a heptapeptide eliminates its cytotoxicity and significantly increases its inhibition

Shuai Ma, Huan Zhang, Xiaoyan Dong, Linling Yu, Jie Zheng, Yan Sun

《化学科学与工程前沿(英文)》 2018年 第12卷 第2期   页码 283-295 doi: 10.1007/s11705-017-1687-2

摘要: Amyloid- (A ) protein aggregation is the main hallmark of Alzheimer’s disease (AD). Inhibition of A fibrillation is thus a promising therapeutic approach to the prevention and treatment of AD. Recently, we designed a heptapeptide inhibitor, LVFFARK (LK7). LK7 shows a promising inhibitory capability on A fibrillation, but is prone to self-assembling and displays high cytotoxicity, which would hinder its practical application. Herein, we modified LK7 by a head-to-tail cyclization and obtained a cyclic LK7 (cLK7). cLK7 exhibits a different self-assembly behavior from LK7, and has higher stability against proteolysis than LK7 and little cytotoxicity to SH-SY5Y cells. Thermodynamic analysis revealed that both LK7 and cLK7 could bind to A by electrostatic interactions, hydrogen bonding and hydrophobic interactions, but the binding affinity of cLK7 for A ( = 4.96 µmol/L) is six times higher than that of LK7 ( = 32.2 µmol/L). The strong binding enables cLK7 to stabilize the secondary structure of A and potently inhibit its nucleation, fibrillation and cytotoxicity at extensive concentration range, whereas LK7 could only moderately inhibit A fibrillation and cytotoxicity at low concentrations. The findings indicate that the peptide cyclization is a promising approach to enhance the performance of peptide-based amyloid inhibitors.

关键词: Alzheimer’s disease     amyloid β-protein     cyclic peptide     inhibition     protein aggregation    

Utilizing melt crystallization fundamentals in the development of a new tabletting technology

Ahmed ABOUZEID,Sandra PETERSEN,Joachim ULRICH

《化学科学与工程前沿(英文)》 2014年 第8卷 第3期   页码 346-352 doi: 10.1007/s11705-014-1443-9

摘要: Increasing production effeciency and lowering costs are some of the many advantages melt crystallization technology offers over the conventional methodology of tabletting. A normal tablet consists of a pure shell or a coat and a separate core constituting the pharmaceutical active ingredient. Great emphasis is put on the purity of the shell since its purpose is to solely protect and deliver the active ingredient to its target. Melt crystallization is a purification (separation) process. It is discussed here for its ability to produce coated tablets, by separating the “coating” material from the “to be coated” material coming from one molten mixture. Molten drops of lutrol-ibuprofen mixture are produced using the drop forming technique. The subsequent analysis involves proving and quantifying the phase separation (coat purity). The mechanism of a crystallizing drop is shown as direct evidence of the ongoing process. Moreover, solidified tablet batches are analyzed for the purity of their coating by measuring the ibuprofen concentration. This optimization process is carried out through multiple stages of development and condition enhancements in order to produce the most pure tablet coating. As a result, a trial showing an almost purely coated tablet is presented here.

关键词: phase separation     melt crystallization     tablets     process optimization    

Nucleic acid crystallization and X-ray crystallography facilitated by single selenium atom

Wen Zhang,Jack W. Szostak,Zhen Huang

《化学科学与工程前沿(英文)》 2016年 第10卷 第2期   页码 196-202 doi: 10.1007/s11705-016-1565-3

摘要: X-ray crystallography is a powerful strategy for 3-D structure determination of macromolecules, such as nucleic acids and protein-nucleic acid complexes. However, the crystallization and phase determination are the major bottle-neck problems in crystallography. Recently we have successfully developed synthesis and strategy of selenium-derivatized nucleic acids (SeNA) for nucleic acid crystallography. SeNA might not only provide the rational strategies to solve the phase determination problem, but also offer a potential strategy to explore crystallization solutions.

关键词: selenium     DNA     RNA     nucleic acid     crystallization    

Preparation and crystallization kinetics of micron-sized Mg(OH)

Xingfu SONG, Kefeng TONG, Shuying SUN, Ze SUN, Jianguo YU

《化学科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 130-138 doi: 10.1007/s11705-013-1332-7

摘要: Magnesium hydroxide is an important chemical, and is usually obtained from seawater or brine via precipitation process. The particle size distribution of magnesium hydroxide has great effects on the subsequent filtration and drying processes. In this paper, micron-sized magnesium hydroxide with high purity, large particle size and low water content in filter cake was synthesized via simple wet precipitation in a mixed suspension mixed product removal (MSMPR) crystallizer. The effects of reactant concentration, residence time and impurities on the properties of magnesium hydroxide were investigated by X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Malvern laser particle size analyzer. The results show that NaOH concentration and residence time have great effects on the water content and particle size of Mg(OH) . The spherical Mg(OH) with uniform diameter of about 30 μm was obtained with purity higher than 99% and water content less than 31%. Furthermore, the crystallization kinetics based on the population balance theory was studied to provide the theoretical data for industrial enlargement, and the simulation coefficients ( ) based on ASL model and C-R model are 0.9962 and 0.9972, respectively, indicating that the crystal growth rate of magnesium hydroxide can be well simulated by the size-dependent growth models.

关键词: magnesium hydroxide     precipitation     micron-sized     crystallization kinetics    

Applications of the crystallization process in the pharmaceutical industry

Sohrab ROHANI

《化学科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 2-9 doi: 10.1007/s11705-009-0297-z

摘要: The applications of the crystallization technique in the pharmaceutical industry as a purification and separation process for the isolation and synthesis of pure active pharmaceutical ingredients (API), co-crystals, controlled release pulmonary drug delivery, and separation of chiral isomers are briefly discussed using a few case studies. The effect of process variables and solvent on the polymorphism and morphology of stavudine is discussed. The implementation of external control in the form of feedback and real-time optimal control using cooling and antisolvent crystallization of paracetamol in water-isopropyl alcohol is introduced. Two methods to prepare micron-sized drug particles, namely, micro-crystallization and polymer-coated API-loaded magnetic nanoparticles for pulmonary drug delivery, are discussed. The significance of co-crystals in drug administration is highlighted using the theophylline-nicotinamide co-crystal system. Resolution of chloromandelic acid derivatives, a racemic compound, is achieved using direct crystallization and diastereomeric salts crystallization. The crystal structures of diastereomeric salts of chloromandelic acid and phenylethylamine are determined. The structure comparison between the less soluble and more soluble salts shows that weak interactions such as CH/π interactions and van der Waals forces contribute to chiral recognition when the hydrogen bonding patterns are similar.

关键词: feedback     morphology     pulmonary     paracetamol     recognition    

标题 作者 时间 类型 操作

Theoretical insights into influence of additives on sulfamethoxazole crystal growth kinetics and mechanisms

期刊论文

Chronic inhibition of cyclic guanosine monophosphate-specific phosphodiesterase 5 prevented cardiac fibrosisthrough inhibition of transforming growth factor β-induced Smad signaling

null

期刊论文

Progress in membrane distillation crystallization: Process models, crystallization control and innovative

Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He

期刊论文

Effects of a structurally related substance on the crystallization of paracetamol

Ali SALEEMI, I.I. ONYEMELUKWE, Zoltan NAGY

期刊论文

Interfacial induction and regulation for microscale crystallization process: a critical review

期刊论文

simultaneous anammox and denitrification system with short-term pyridine exposure: Process capability, inhibition

期刊论文

ROOT EXUDATES FROM CANOLA EXHIBIT BIOLOGICAL NITRIFICATION INHIBITION AND ARE EFFECTIVE IN INHIBITING

期刊论文

Inhibition character of crotonaldehyde manufacture wastewater on biological acidification

期刊论文

Roles of integrin β3 cytoplasmic tail in bidirectional signal transduction in a trans-dominant inhibition

null

期刊论文

The feasibility of coating by cooling crystallization on ibuprofen naked tablets

Fatima Mameri, Ouahiba Koutchoukali, Mohamed Bouhelassa, Anne Hartwig, Leila Nemdili, Joachim Ulrich

期刊论文

Head-to-tail cyclization of a heptapeptide eliminates its cytotoxicity and significantly increases its inhibition

Shuai Ma, Huan Zhang, Xiaoyan Dong, Linling Yu, Jie Zheng, Yan Sun

期刊论文

Utilizing melt crystallization fundamentals in the development of a new tabletting technology

Ahmed ABOUZEID,Sandra PETERSEN,Joachim ULRICH

期刊论文

Nucleic acid crystallization and X-ray crystallography facilitated by single selenium atom

Wen Zhang,Jack W. Szostak,Zhen Huang

期刊论文

Preparation and crystallization kinetics of micron-sized Mg(OH)

Xingfu SONG, Kefeng TONG, Shuying SUN, Ze SUN, Jianguo YU

期刊论文

Applications of the crystallization process in the pharmaceutical industry

Sohrab ROHANI

期刊论文