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1.
Cryst Growth Des ; 23(11): 8163-8172, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37937191

ABSTRACT

Herein, we study the influences of the laser-exposed volume and the irradiation position on the nonphotochemical laser-induced nucleation (NPLIN) of supersaturated potassium chloride solutions in water. The effect of the exposed volume on the NPLIN probability was studied by exposing distinct milliliter-scale volumes of aqueous potassium chloride solutions stored in vials at two different supersaturations (1.034 and 1.050) and laser intensities (10 and 23 MW/cm2). Higher NPLIN probabilities were observed with increasing laser-exposed volume as well as with increasing supersaturation and laser intensity. The measured NPLIN probabilities at different exposed volumes are questioned in the context of the dielectric polarization mechanism and classical nucleation theory. No significant change in the NPLIN probability was observed when samples were irradiated at the bottom, top, or middle of the vial. However, a significant increase in the nucleation probability was observed upon irradiation through the solution meniscus. We discuss these results in terms of mechanisms proposed for NPLIN.

2.
Cryst Growth Des ; 23(8): 6067-6080, 2023 Aug 02.
Article in English | MEDLINE | ID: mdl-37547880

ABSTRACT

Non-photochemical laser-induced nucleation (NPLIN) has emerged as a promising primary nucleation control technique offering spatiotemporal control over crystallization with potential for polymorph control. So far, NPLIN was mostly investigated in milliliter vials, through laborious manual counting of the crystallized vials by visual inspection. Microfluidics represents an alternative to acquiring automated and statistically reliable data. Thus we designed a droplet-based microfluidic platform capable of identifying the droplets with crystals emerging upon Nd:YAG laser irradiation using the deep learning method. In our experiments, we used supersaturated solutions of KCl in water, and the effect of laser intensity, wavelength (1064, 532, and 355 nm), solution supersaturation (S), solution filtration, and intentional doping with nanoparticles on the nucleation probability is quantified and compared to control cooling crystallization experiments. Ability of dielectric polarization and the nanoparticle heating mechanisms proposed for NPLIN to explain the acquired results is tested. Solutions with lower supersaturation (S = 1.05) exhibit significantly higher NPLIN probabilities than those in the control experiments for all laser wavelengths above a threshold intensity (50 MW/cm2). At higher supersaturation studied (S = 1.10), irradiation was already effective at lower laser intensities (10 MW/cm2). No significant wavelength effect was observed besides irradiation with 355 nm light at higher laser intensities (≥50 MW/cm2). Solution filtration and intentional doping experiments showed that nanoimpurities might play a significant role in explaining NPLIN phenomena.

3.
J Agric Food Chem ; 71(28): 10500-10524, 2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37417462

ABSTRACT

Achieving rapid global agricultural development while maintaining ecological harmony is a major challenge of the new millennium. Meeting this challenge requires the development of efficient and environmentally friendly agrochemicals, including pesticides and fertilizers. Molecular assembly, as a promising strategy, has garnered significant attention in recent years for the development of advanced solid-state forms of agrochemicals. In this review, we present the potential and recent advancements of solid-state forms, such as polymorphs, cocrystals/salts, solvates, inclusion compounds, and the amorphous state, for the production of high-efficiency and low-polluting agrochemical products. We provide an overview of the concepts and preparation methods of these solid-state forms, followed by an exploration of their applications in sustainable agriculture. Specifically, we highlight their value in enhancing pesticide solubility, enabling controlled release of chemical fertilizers, and reducing off-target risks. Lastly, we discuss the challenges and prospects associated with the utilization of solid-state forms for the advancement of environmentally friendly and efficient agriculture.


Subject(s)
Agrochemicals , Pesticides , Agrochemicals/chemistry , Fertilizers , Nanotechnology , Agriculture , Pesticides/chemistry
4.
Bioresour Technol ; 385: 129461, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37423545

ABSTRACT

Valorization of lignocellulose has received a lot of attention due to the abundance of lignocellulosics. It was showed that synergistic carbohydrate conversion and delignification could be achieved via ethanol assisted DES (choline chloride/lactic acid) pretreatment. To explore the reaction mechanism of lignin in the DES, milled wood lignin obtained from Broussonetia papyrifera was subjected to pretreatment at critical temperatures. The results suggested that ethanol assistance could contribute the incorporation of ethyl groups and reduce condensation structures of Hibbert's ketone. Adding ethanol at 150 °C not only decreased formation of condensed G unit (from 7.23% to 0.87%), but also removed J and S' substructures, thus effectively reducing the adsorption of lignin on cellulase, and promoting the glucose yield after enzymatic hydrolysis.


Subject(s)
Ethanol , Lignin , Lignin/chemistry , Solvents , Deep Eutectic Solvents , Hydrolysis , Biomass
5.
RSC Adv ; 13(18): 12175-12183, 2023 Apr 17.
Article in English | MEDLINE | ID: mdl-37091620

ABSTRACT

The high risk of solution-mediated phase transformation (SMPT) from the metastable monohydrate to stable Form I makes it difficult to produce pure metastable monohydrate of calcium d-gluconate. In this work, we explored the effect of various operating parameters on the SMPT of calcium d-gluconate in water and proposed an effective approach to obtain the desired monohydrate. First, the two forms of calcium d-gluconate were characterized and compared using powder X-ray diffraction (PXRD), thermal analysis, and Raman spectroscopy. The lower solubility of Form I in water illustrates its higher thermodynamic stability than monohydrate when the temperature is higher than 292 K. Afterward, the SMPT of calcium d-gluconate from monohydrate to Form I was investigated in water using in situ Raman spectroscopy combined with scanning electron microscopy and PXRD. Results showed that the nucleation and growth of Form I was the rate-limiting step in the SMPT from monohydrate to Form I. The phase transformation from monohydrate to Form I was delayed to produce pure monohydrate by decreasing temperature and agitation rate, reducing the amount of solid loading, and increasing the particle size of solid loading. Furthermore, the transformation kinetics were studied by the JMA model to explore how temperature influences the SMPT process. This study enriches the study of the calcium d-gluconate SMPT mechanism, and also provides guidance for obtaining high-quality injection-grade calcium gluconate monohydrate.

6.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 41(2): 243-246, 2023 Apr 01.
Article in English, Chinese | MEDLINE | ID: mdl-37056193

ABSTRACT

Dental erosion is characterized by progressively destroyed teeth, which has no relation to bacteria but to chemicals. Some internal factors, such as gastroesophageal reflux induced by bulimia, anorexia, gastrointestinal diseases, or drugs, and external factors, such as diet, drugs, and occupational acid exposure, are considered promotive factors for this disease. This article presents a patient suffering from severe dental erosion in the whole dentition, especially in the maxillary teeth, due to gastroesophageal reflux induced by glucocorticoid therapy for optic neuritis. This article discusses the mechanism between optic neuritis glucocorticoid therapy and dental erosion.


Subject(s)
Gastroesophageal Reflux , Tooth Erosion , Humans , Glucocorticoids/therapeutic use , Tooth Erosion/etiology , Tooth Erosion/therapy , Gastroesophageal Reflux/complications
7.
Int J Mol Sci ; 23(9)2022 May 07.
Article in English | MEDLINE | ID: mdl-35563618

ABSTRACT

Hydrogenation of CO2 to form methanol utilizing green hydrogen is a promising route to realizing carbon neutrality. However, the development of catalyst with high activity and selectivity to methanol from the CO2 hydrogenation is still a challenge due to the chemical inertness of CO2 and its characteristics of multi-path conversion. Herein, a series of highly active carbon-confining molybdenum sulfide (MoS2@C) catalysts were prepared by the in-situ pyrolysis method. In comparison with the bulk MoS2 and MoS2/C, the stronger interaction between MoS2 and the carbon layer was clearly generated. Under the optimized reaction conditions, MoS2@C showed better catalytic performance and long-term stability. The MoS2@C catalyst could sustain around 32.4% conversion of CO2 with 94.8% selectivity of MeOH for at least 150 h.


Subject(s)
Carbon Dioxide , Methanol , Carbon , Hydrogenation , Molybdenum
8.
Bioresour Technol ; 350: 126885, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35217157

ABSTRACT

A novel pretreatment system containing deep eutectic solvents and ethanol (DES-E) for synergistic carbohydrate conversion and delignification was reported in this study. The DES-E pretreatment resulted in an enhanced glucose yield compared to individual DES and ethanol pretreatment for the three tested biomass, including Broussonetia papyrifera, corn stover and pine. To further explore the delignification mechanism, the solubilized lignin and residual lignin from Broussonetia papyrifera was recovered and extracted, then thoroughly characterized. The highest total OH content was found in the DES-E solubilized lignin, which could be used as antioxidant. The presence of ethanol in pretreatment liquor could protect the ß-O-4 substructure from breakage and reduce lignin condensation, which favors the subsequent enzymatic hydrolysis. Comparable glucose yield and delignification performance was achieved by recycled DES. DES-E pretreatment offers a promising method for lignin isolation and cellulose digestibility improvement simultaneously.


Subject(s)
Deep Eutectic Solvents , Lignin , Biomass , Ethanol , Hydrolysis , Lignin/chemistry , Solvents/chemistry
9.
Front Bioeng Biotechnol ; 10: 1115469, 2022.
Article in English | MEDLINE | ID: mdl-36698646

ABSTRACT

Introduction: A combination of deep eutectic solvent with ethanol was developed for pretreatment of Broussonetia papyrifera to effectively extract lignin and promote the subsequent enzymatic hydrolysis. Methods: In order to further explore the optimal conditions for enzymatic hydrolysis, a central composite design method was applied. Results and Discussion: The correlation between each factor and glucose yield was obtained, and the optimal conditions was 160°C, 60 min, the ratio of DES to E was 1/1 (mol/mol). The results showed that compared with control, the glucose yield increased by 130.67% under the optimal pretreatment conditions. Furthermore, the specific surface area of biomass was increased by 66.95%, and the content of xylan and lignin was decreased by 86.71% and 85.83%. The correlation between xylan/lignin removal and enzymatic hydrolysis showed that the removal of lignin facilitated the glucose yield more significantly than that of xylan. To further explore the lignin valorization, the structural and antioxidant analysis of recovered lignin revealed that high temperature was favorable for lignin with good antioxidant performance. This pretreatment is a promising method for separating lignin with high antioxidant activity and improving cellulose digestibility.

10.
Histol Histopathol ; 33(1): 89-99, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28345127

ABSTRACT

Nitrogen-containing bisphosphonates (N-BPs) are potent antiresorptive drugs and their actions on osteoclasts have been studied extensively. Recent studies have suggested that N-BPs also target bone-forming cells. However, the precise mechanism of N-BPs in osteoblasts is paradoxical, and the specific role of osteocytes is worthy of in-depth study. Here, we investigated the cellular mechanisms of N-BPs regulating bone defect healing by zoledronate (ZA). Bone histomorphometry confirmed an increase in new bone formation by systemic ZA administration. ZA induced more alkaline phosphatase-positive osteoblasts and tartrate-resistant acid phosphatase-positive osteoclasts residing on the bone surface. Inexplicably, ZA increased SOST expression in osteocytes embedded in the bone matrix, which was not compatible with the intense osteoblast activity on the bone surface. ZA induced heterogeneous osteocytes and disturbed the distribution of the osteocytic-canalicular system (OLCS). Furthermore, according to the degree of OLCS regularity, dentin matrix protein 1 reactivity had accumulated around osteocytes in the ZA group, but it was distributed evenly in the OLCS of the control group. The control group showed a dense array of the gap junction protein connexin 43. However, connexin 43 was extremely sparse after ZA administration. In summary, ZA treatment reduces gap junction connections and blocks cellular communication between osteocytes and osteoblasts. Retaining SOST expression in osteocytes leads to activation of the Wnt signaling pathway and subsequent bone formation.


Subject(s)
Bone Density Conservation Agents/pharmacology , Cell Communication/drug effects , Diphosphonates/pharmacology , Femoral Fractures/drug therapy , Fracture Healing/drug effects , Imidazoles/pharmacology , Osteoblasts/drug effects , Osteocytes/drug effects , Osteogenesis/drug effects , Adaptor Proteins, Signal Transducing , Alkaline Phosphatase/metabolism , Animals , Connexin 43/metabolism , Disease Models, Animal , Extracellular Matrix Proteins/metabolism , Femoral Fractures/metabolism , Femoral Fractures/pathology , Femoral Fractures/physiopathology , Glycoproteins/metabolism , Intercellular Signaling Peptides and Proteins , Male , Mice , Osteoblasts/metabolism , Osteoblasts/pathology , Osteoclasts/drug effects , Osteoclasts/metabolism , Osteoclasts/pathology , Osteocytes/metabolism , Osteocytes/pathology , Signal Transduction/drug effects , Tartrate-Resistant Acid Phosphatase/metabolism , Time Factors , Zoledronic Acid
11.
Mol Med Rep ; 11(5): 3642-6, 2015 May.
Article in English | MEDLINE | ID: mdl-25544110

ABSTRACT

A subset of cancer stem cells termed 'side population' (SP) cells has been identified in several types of solid tumor and is known to be responsible for the failure of chemotherapy and for cancer relapse. In the present study, the oral squamous cell carcinoma (OSCC) cell line SCC­55 was used for analysis of the SP cells based on Hoechst 33342 exclusion, via the ATP­binding cassette (ABC) transporter, with and without verapamil using fluorescence activated cell sorting. The results demonstrated that the presence of SP cells in the SCC­55 cell line was 2.8%, which was reduced to 0.6% in the presence of verapamil, an inhibitor of the ABC transporter. In addition, following exposure to the chemotherapeutic drug 5­fluorouracil, a high survival rate was observed in the SP cells due to overexpression of the ABCG2 and B­cell lymphoma 2 proteins. In addition, overexpression of stem cell surface markers, including CD44 and CD147 was observed in the SP cells. Therefore, these findings suggested that OSCC contains SP cells, which share certain characteristics with stem cells. The coexpression of ABC transporters and stem cell surface markers in SP cells may be associated with resistance to chemotherapeutic agents and also supports a role for these cells in tumor recurrence, metastasis and invasion.


Subject(s)
Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Mouth Neoplasms/metabolism , Mouth Neoplasms/pathology , Neoplastic Stem Cells/metabolism , Side-Population Cells/metabolism , ATP Binding Cassette Transporter, Subfamily B, Member 1/metabolism , Biomarkers, Tumor , Cell Line, Tumor , Cell Separation , Humans , Immunophenotyping
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