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1.
Ultrason Sonochem ; 108: 106953, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38879963

RESUMO

Liquid-liquid separation, commonly referred to as oiling-out, frequently can occurs during crystallization, especially the anti-solvent crystallization process of phosphoryl compounds, and poses potential hurdle for high-quality product. Efficiently regulating oiling-out during crystallization remains a significant challenge. Among various techniques, ultrasound emerges as a green and effective approach to enhance the crystallization process. However, there is a dearth of in-depth research exploring the microscopic mechanisms of this process. Therefore, our research focused on the fructose-1,6-diphosphate (FDP), a typical phosphoryl compound, to gain a deeper understanding of how ultrasound influences the oiling-out process. The focused beam reflectance measurement (FBRM) technology was used to investigate the oiling-out phenomenon of FDPNa3 across various solvent ratios. In addition, the influence of ultrasound on the induction time was studied and the nucleation energy barrier was calculated. Finally, to further unravel the microscopic mechanisms, we utilized molecular simulation techniques to analyze the impact of ultrasound power on the dissolution-precipitation process. Our observations revealed a consistent oiling-out process that attainted a stable state regardless of the solvent employed. Notably, the results of the oiling-out induction time experiments indicated that ultrasound significantly reduced helped lower the nucleation energy barrier of FDP3- ions, thereby dismantling FDP3-clusters in solution. Thus, in turn, shortened the reduced induction time and promoted crystallization. Furthermore, ultrasound reduced the interactions between FDP3-ions and water molecules as well as FDP3- ions themselves. As simulated field intensity increased, these interaction forces gradually diminished, the thickness of the hydration layer surrounding the FDP3- clusters facilitating the disruption of clusters, ultimately enhancing the crystallization process.

2.
ACS Omega ; 8(28): 25288-25294, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37483214

RESUMO

Cytidine is an important kind of nucleoside that can be applied to drug development and food industry. Cytidine sulfate is one of its popular forms, which is promising as a medicinal intermediate, especially in antiviral and antitumor drugs. Product refining is the key point of industrial development, and crystallization is a significant way of refining. In this work, the solubility of cytidine sulfate in pure water from 278.15 to 328.15 K and in water-ethanol binary solvents at 298.15 K was measured by the UV spectroscopic method. The solubility data were correlated with temperature and solvent composition using the modified Apelblat, van't Hoff, and CNIBS/R-K equations. On this basis, we investigated and compared three crystallization processes, and the coupling method was developed to prepare crystals with a large particle size, concentrated distribution, and high yield and packing density. In addition, the structure and stability of the products were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and dynamic vapor sorption analysis. It was found that cytidine sulfate has only one crystal form in our research process, and the product of coupling crystallization is stable and favorable for industrial development.

3.
Front Nutr ; 10: 1131542, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875843

RESUMO

Introduction: Natural melanin from Auricularia heimuer have numerous beneficial biological properties, which were used as a safe and healthy colorant in several industries. Methods: In this study, single-factor experiments, Box-Behnken design (BBD), and response surface methodology (RSM) were employed to investigate the effects of alkali-soluble pH, acid precipitation pH, and microwave time on the extraction yield of Auricularia heimuer melanin (AHM) from fermentation. Ultraviolet-visible spectrum (UV-Vis), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), and high-performance liquid chromatography (HPLC) were used to analyze the extracted AHM. The solubility, stability, and antioxidant activities of AHM were also measured. Results: The results showed that alkali-soluble pH, acid precipitation pH, and microwave time significantly affected the AHM yield, with the following optimized microwave-assisted extraction conditions: alkali-soluble pH of 12.3, acid precipitation pH of 3.1, and microwave time of 53 min, resulting in an AHM extraction yield of 0.4042%. AHM exhibited a strong absorption at 210 nm, similar to melanin from other sources. FT-IR spectroscopy also revealed that AHM exhibited the three characteristic absorption peaks of natural melanin. The HPLC chromatogram profile of AHM showed a single symmetrical elution peak with a 2.435 min retention time. AHM was highly soluble in alkali solution, insoluble in distilled water and organic solvents, and demonstrated strong DPPH, OH, and ABTS free radical scavenging activities. Discussion: This study provides technical support to optimize AHM extraction for use in the medical and food industries.

4.
Environ Technol ; 44(17): 2503-2511, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35084292

RESUMO

As the most widely applied process for biological phosphorus removal, enhanced biological phosphorus removal (EBPR) relies on phosphorus accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs), whose function is crucial for the removal of phosphorus. In this study, the effect of zinc oxide nanoparticles (ZnO NPs, 0-50 mg/L) on EBPR performance was investigated in both long-term reactors and batch experiments. It was found that the performance of biological phosphorus removal was recovered from 0% (day 0) to >99% (day 70) after long-term exposure of ZnO NPs (50 mg/L). Further studies revealed that ZnO NPs treatment caused no significant effects on the morphology and settleability of activated sludge, but enhanced the release and uptake of phosphorus as well as the transformations of polyhydroxyalkanoates and glycogen in activated sludge, which suggested that PAOs were re-activated during long-term exposure to ZnO NPs. Fluorescence in-situ hybridization (FISH) analysis showed that the relative abundance of PAOs was increased after long-term exposure. Meanwhile, the enzymatic activities of PPX and PPK were also enhanced. These results indicated that compared with short-term exposure, long-term exposure to ZnO NPs favours PAOs function and thus led to the recovery of biological phosphorus removal.


Assuntos
Óxido de Zinco , Esgotos , Fósforo , Polifosfatos , Glicogênio , Reatores Biológicos
5.
Molecules ; 24(20)2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31623085

RESUMO

MIL-100(Fe, Cr) and MIL-101(Cr) were synthesized by the hydrothermal method and applied to the adsorptions of five aromatic amines from aqueous solutions. These three metal-organic frameworks (MOFs) were well characterized by powder X-ray diffraction (PXRD), scanning electron microscope (SEM), transmission electron microscope (TEM), thermogravimetric analysis (TGA) and surface area analysis. The adsorption mechanism of three MOFs and the effects of the structures of MOFs on the adsorption of aromatic amines were discussed. The results show that the cavity system and suitable hydrogen bond acceptor were important factors for the adsorption for five aromatic amines of aniline, 1-naphthalamine, o-toluidine, 2-amino-4-nitrotoluene and 2-nitroaniline: (a) the saturated adsorption capacity of aniline, 1-naphthylamine and o-toluidine on MIL-100(Fe) were 52.0, 53.4 and 49.6 mg/g, respectively, which can be attributed to the intermolecular hydrogen bond interaction and cavity system diffusion. (b) The adsorption capacity of 2-nitroaniline and 2-amino-4-nitrotoluene on MIL-101(Cr) were 54.3 and 25.0 mg/g, respectively, which can be attributed to the more suitable pore size of MIL-101(Cr) than that of MIL-100(Fe, Cr). The MOFs of MIL-100(Fe) and MIL-101(Cr) can be potential materials for removing aromatic amines from aqueous solutions.


Assuntos
Aminas/química , Estruturas Metalorgânicas/química , Modelos Químicos , Adsorção , Algoritmos , Estruturas Metalorgânicas/ultraestrutura , Soluções , Termogravimetria , Difração de Raios X
6.
Hepatobiliary Pancreat Dis Int ; 13(4): 348-53, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25100118

RESUMO

BACKGROUND: Laparoscopic cholecystectomy (LC) is one of the most frequent abdominal surgical procedures. The present meta-analysis aimed to estimate the clinical effects of implementing a clinical pathway for LC compared with standard medical care by evaluating the length of hospital stay, costs, and the outcomes of patients undergoing LC. DATA SOURCES: Data were extracted from the following databases: PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, Chinese Medical Citation Index (CMCI), Chinese Medical Current Contents (CMCC), and China BioMedical Literature Database (CBM). We also searched the reference lists of the relevant articles and conference articles. Only randomized controlled trials and controlled clinical trials published from 1980 to 2013 were included. We did not set restrictions on language and country of publications. All of the data were evaluated and analyzed by two reviewers independently with RevMan software (version 5.0). RESULTS: A total of 7 trials with 1187 patients were included. The patients who underwent LC with clinical pathway had shorter hospital stay [weighted mean difference=-1.90, 95% CI: -2.65 to -1.16, P<0.00001], lower cost [standard mean difference=-0.69, 95% CI: -0.82 to -0.56, P<0.00001], and better questionnaires based satisfaction with the medical services. CONCLUSIONS: The applications of the clinical pathway for LC effectively reduced hospital stay and total costs. However, there was insufficient evidence for proving the differences in postoperative complications. Future research should focus on patient outcomes and identify the mechanisms underlying the effect of the clinical pathway.


Assuntos
Colecistectomia Laparoscópica , Procedimentos Clínicos , Distribuição de Qui-Quadrado , Colecistectomia Laparoscópica/efeitos adversos , Colecistectomia Laparoscópica/economia , Redução de Custos , Procedimentos Clínicos/economia , Custos Hospitalares , Humanos , Tempo de Internação , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/terapia , Fatores de Tempo , Resultado do Tratamento
7.
Gynecol Obstet Invest ; 77(2): 137-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24481003

RESUMO

Herlyn-Werner-Wunderlich syndrome (HWWS) is a müllerian duct anomaly typically associated with a uterus didelphys with two cervices and two vaginas, one of which is obstructed. A remarkable case of HWWS with contralateral duplex kidneys and duplication of ureters is described, which, to our knowledge, is a rarely reported variant to date. For this congenital anomaly, a strong suspicion and knowledge of HWWS are essential for a precise diagnosis.


Assuntos
Anormalidades Múltiplas/diagnóstico , Ductos Paramesonéfricos/anormalidades , Anormalidades Urogenitais/diagnóstico , Anormalidades Múltiplas/diagnóstico por imagem , Adulto , Feminino , Humanos , Radiografia , Síndrome , Resultado do Tratamento , Ultrassonografia , Anormalidades Urogenitais/diagnóstico por imagem , Anormalidades Urogenitais/cirurgia
8.
World J Gastroenterol ; 17(47): 5214-20, 2011 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-22215947

RESUMO

AIM: To conduct a meta-analysis to determine the relative merits of robotic surgery (RS) and laparoscopic surgery (LS) for rectal cancer. METHODS: A literature search was performed to identify comparative studies reporting perioperative outcomes for RS and LS for rectal cancer. Pooled odds ratios and weighted mean differences (WMDs) with 95% confidence intervals (95% CIs) were calculated using either the fixed effects model or random effects model. RESULTS: Eight studies matched the selection criteria and reported on 661 subjects, of whom 268 underwent RS and 393 underwent LS for rectal cancer. Compared the perioperative outcomes of RS with LS, reports of RS indicated favorable outcomes considering conversion (WMD: 0.25; 95% CI: 0.11-0.58; P = 0.001). Meanwhile, operative time (WMD: 27.92, 95% CI: -13.43 to 69.27; P = 0.19); blood loss (WMD: -32.35, 95% CI: -86.19 to 21.50; P = 0.24); days to passing flatus (WMD: -0.18, 95% CI: -0.96 to 0.60; P = 0.65); length of stay (WMD: -0.04; 95% CI: -2.28 to 2.20; P = 0.97); complications (WMD: 1.05; 95% CI: 0.71-1.55; P = 0.82) and pathological details, including lymph nodes harvested (WMD: 0.41, 95% CI: -0.67 to 1.50; P = 0.46), distal resection margin (WMD: -0.35, 95% CI: -1.27 to 0.58; P = 0.46), and positive circumferential resection margin (WMD: 0.54, 95% CI: 0.12-2.39; P = 0.42) were similar between RS and LS. CONCLUSION: RS for rectal cancer is superior to LS in terms of conversion. RS may be an alternative treatment for rectal cancer. Further studies are required.


Assuntos
Laparoscopia/instrumentação , Laparoscopia/métodos , Neoplasias Retais/cirurgia , Robótica/métodos , Ensaios Clínicos como Assunto , Intervalos de Confiança , Bases de Dados Factuais , Humanos , Resultado do Tratamento
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