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1.
Food Chem ; 400: 134032, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36055145

RESUMO

The formation mechanism of heat-induced egg yolk granules (EYGs)/sodium alginate (SA) emulsion gel was studied under pH 6.2 and 7.5. Particle size, water holding capacity, LF NMR, and protein solubility revealed that pH 7.5 increased the surface charge of EYGs and enhanced non-covalent interaction with SA, and hydrogen bonding dominated of the gel formation process. Microscopy and rheological analysis indicated that samples with 0.75% SA had the smallest particle size and highest G', with chain-like oil droplets. Excess SA (1%) led to depletion flocculation due to SA structural rearrangements around oil droplets caused by the increase in negatively charged, causing uneven network structure. The in vitro release property and storage stability of ß-carotene loaded in the EYGs/SA emulsion gel showed that SA increased storage stability and decreased bioaccessibility of ß-carotene with delayed digestion rate. These results provide a theoretical basis for the nutrient delivery system in gel foods.


Assuntos
Alginatos/química , Gema de Ovo/química , beta Caroteno/química , Emulsões/química , Géis/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Imageamento por Ressonância Magnética/métodos , Tamanho da Partícula , Proteínas/química , Reologia , Solubilidade , Água/química
2.
Inorg Chem ; 61(18): 7103-7110, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35482439

RESUMO

Geometric analysis has been guiding the design and construction of metal-organic polyhedra. Here, a series of isohedral tetrahedra ZrIT-1 and -2 and VIT-1 and -2 were synthesized by a one-pot method relying on trivalent molecular building blocks. Structural analysis shows that the isohedral tetrahedra constructed with {V6(SO4)(CO2)3} have three different sets of prism lengths, while those constructed with {Zr3O(CO2)3} have two different sets of prism lengths. Comparison of two types of polyhedra reveals that the different sizes and coordination flexibilities of the two MBBs result in different cavity volumes. The environmentally toxic oxoanion trapping ability of ZrIT-1 was explored due to its structural stability and cation cage properties. The results show that ZrIT-1 can capture permanganate and dichromate anions in water with high efficiency and selectivity. Notably, the permanganate adsorption capacity can reach ∼276.6 mg/g, which exceeds those of most metal-organic framework materials. In addition, the adsorption and desorption of iodine showed that ZrIT-1 has a reversible adsorption capacity for iodine.


Assuntos
Iodo , Estruturas Metalorgânicas , Adsorção , Dióxido de Carbono , Iodetos , Estruturas Metalorgânicas/química , Metais
3.
Nat Commun ; 11(1): 4103, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796853

RESUMO

Inspired by the structures of virus capsids, chemists have long pursued the synthesis of their artificial molecular counterparts through self-assembly. Building nanoscale hierarchical structures to simulate double-shell virus capsids is believed to be a daunting challenge in supramolecular chemistry. Here, we report a double-shell cage wherein two independent metal-organic polyhedra featuring Platonic and Archimedean solids are nested together. The inner (3.2 nm) and outer (3.3 nm) shells do not follow the traditional "small vs. large" pattern, but are basically of the same size. Furthermore, the assembly of the inner and outer shells is based on supramolecular recognition, a behavior analogous to the assembly principle found in double-shell viruses. These two unique nested characteristics provide a new model for Matryoshka-type assemblies. The inner cage can be isolated individually and proves to be a potential molecular receptor to selectively trap guest molecules.

4.
Pak J Med Sci ; 36(2): 59-63, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32063932

RESUMO

OBJECTIVE: To find out the application value of minimally invasive percutaneous dilational tracheostomy in critically ill patients in intensive care unit (ICU). METHODS: One hundred and forty critically ill patients who underwent tracheostomy in ICU of our hospital were included in the study from August 2016 to December 2017. They were divided into an observation group and a control group by random number table method, 70 in each group. The control group received conventional tracheotomy, while the observation group received percutaneous dilational tracheostomy. The operation time, incision length, amount of intraoperative bleeding and healing time of incision were compared between the two groups, and the changes of vital signs and complications after operation were recorded. The family members of the patients signed the informed consent. RESULTS: The operation time, healing time and incision length of the observation group were (9.92±4.13) min, (1.31±0.21) cm and (6.91±0.72) d respectively, shorter than (24.09±6.82) min, (3.40±0.65) cm and (67.48±0.61) d in the control group, and the differences were statistically significant (P<0.05). The amount of intraoperative bleeding of the observation group was (7.81±1.83) mL, less than (16.34±2.83) mL in the control group; the difference was statistically significant (P<0.05). The heart rate and oxygen saturation of the observation group before and during the operation were not significantly different (P>0.05). The heart rate of the control group during the operation was significantly higher than that before the operation (P<0.05); the oxygen saturation of the control group before and during the operation had no significant difference (P>0.05). The incidence of complications in the observation group was 24.3%, which was significantly lower than that in the control group (55.7%, X2=8.279, P=0.014). CONCLUSION: Minimally invasive percutaneous dilational tracheostomy has advantages of small trauma, less infection and beautiful incision, and it will not increase postoperative complications. It is of great value in the treatment of ICU critical patients.

5.
J Electrocardiol ; 59: 112-115, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32062379

RESUMO

Pheochromocytoma is a neuroendocrine tumor of the adrenal gland that secretes excess amount of catecholamine, which in turn leads to extremely varied clinical manifestations, such as hypertension, headache, sweating and palpitations. This eventually leads to delay or mistakes in diagnosing the disease. This could be fatal due to misdiagnosis as it receives a totally different treatment. We herein reported a case of pheochromocytoma with recurrent ventricular tachycardia. A literature review was conducted to investigate the clinical features of these patients.


Assuntos
Neoplasias das Glândulas Suprarrenais , Feocromocitoma , Taquicardia Ventricular , Neoplasias das Glândulas Suprarrenais/complicações , Neoplasias das Glândulas Suprarrenais/diagnóstico , Catecolaminas , Eletrocardiografia , Humanos , Feocromocitoma/complicações , Feocromocitoma/diagnóstico , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/etiologia
6.
Chemistry ; 25(67): 15326-15332, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31568591

RESUMO

A new supramolecular nanocage, VMOP-31, based on polyoxovanadate as the molecular building block, has been designed and synthesized under solvothermal conditions. The structure of VMOP-31 was determined by single-crystal and powder X-ray diffraction, FTIR spectroscopy, UV/Vis spectrophotometry, and thermogravimetric analysis. The nanocage exhibits octahedral geometry and is constructed of six {V5 O9 Cl(COO)4 } at the vertices and eight TATB (H3 TATB=4,4',4''-(s-triazine-2,4,6-triyl)tribenzoic acid) ligands on the faces. Impressively, VMOP-31 exhibited high efficiency in the inhibition of cell growth of solid tumors, such as human liver cancer cells SMMC-7721, and superior results in the treatment of liver tumors in mice compared with classic cisplatin. Detailed studies revealed that the potential mechanism of cell death induced by VMOP-31 involves cell cycle arrests, DNA damage, and subsequent apoptosis. Moreover, VMOP-31 exhibited negligible side effects in the mice compared with cisplatin. To the best of our knowledge, VMOP-31 is the first supramolecular nanocage applied to hepatic tumors both in vitro and in vivo.

7.
Chemistry ; 25(72): 16617-16624, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31631411

RESUMO

Hybrid materials have obtained well-deserved attention for energy storage devices, because they show high capacitances and high energy densities induced by the synergistic effect between complementary components. Polyoxometalate-based metal-organic frameworks (POMOFs) possess the abundant redox-active sites and ordered structures of polyoxometalates (POMs) and metal-organic frameworks (MOFs), respectively. Here, an asymmetric supercapacitor (ASC) NENU-5/PPy/60//FeMo/C was fabricated in which both its electrodes are prepared from POMOF precursors. A typical POMOF material, NENU-5, was first connected with polypyrrole (PPy) through electrodeposition to form the cathode material NENU-5/PPy. Another representative POMOFs material, PMo12 @MIL-100, was carbonized to obtain the anode material FeMo/C. Cathode NENU-5/PPy exhibited an extraordinary capacitance of 508.62 F g-1 (areal capacitance: 2034.51 mF cm-2 ). In addition, anode FeMo/C shows excellent cyclic stability attributed to its unique structure. Finally, benefiting from the outstanding capacitances and structural merits of the anode and cathode, assembled asymmetric supercapacitor NENU-5/PPy/60//FeMo/C achieves an energy density of 1.12 mWh cm-3 at a power density output of 27.78 mW cm-3 , as well as a notable life of 10 000 cycles with an capacity retention of 80.62 %. Thus, the unique ASC is strongly competitive in high capacitance, long cycle life, and high energy-required energy storage devices.

8.
Angew Chem Int Ed Engl ; 58(14): 4649-4653, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30734443

RESUMO

Design and synthesis of metal-organic polyhedra (MOPs) with targeted geometries from predetermined secondary building units (SBUs) is a long-standing challenge in chemistry and material science. Theoretical prediction shows that there are 6 possible polyhedra from the 3-coordinated, 4-coordinated octahedron ((3,4)-c octahedron) to (3,5)-c icosahedron with minimal transitivity (simplest possible). Except for one missing polyhedron (mtr) due to the unfavorable angles, we report five MOPs based on these structures, including an octahedral (3,4)-c VMOP-21 (rdo), an icosahedral (3,5)-c VMOP-25 (trc), and three intermediate derived trinodal (3,4,5)-c VMOP-22-24 (ghm, hmg, xum). Remarkably, all these MOPs obey the minimal transitivity principle and are consistent with geometrical predictions.

9.
J Am Chem Soc ; 140(50): 17365-17368, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30452251

RESUMO

Nanoscale regular polyhedra with icosahedral symmetry exist naturally as exemplified by virus capsids and fullerenes. Nevertheless, their generation by supramolecular chemistry through the linking of 5-fold symmetry vertices remains unmet because of the absence of 5-fold symmetry building blocks with the requisite geometric features. This situation contrasts with that of tetrahedral and octahedral symmetry metal-organic polyhedra (MOPs), for which appropriate triangular and square molecular building blocks (MBBs) that can serve as vertices or faces are readily available. Herein, we report isolation of a pentagonal [WV5O11(SO4)6]8- cluster and reveal its utility to afford the first four examples of nanoscale Goldberg MOPs, based upon 5-fold MBBs. Two 32-faced G v(1,1) MOPs and two 42-faced G v(2,0) MOPs were formed using linear or triangular organic ligands, respectively. The largest Goldberg MOP-4, exhibits a diameter of 4.3 nm, can trap fullerene C60 molecules in its interstitial cavities.

10.
Exp Ther Med ; 11(5): 1788-1794, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27168804

RESUMO

In the present study a eukaryotic expression vector of varicella zoster virus (VZV) glycoprotein E (gE) was constructed and enabled to express in COS7 cells. Furthermore, a specific immune response against the VZV gE eukaryotic expression plasmid was induced in BALB/c mice. The VZV gE gene was amplified using polymerase chain reaction (PCR) and cloned into a eukaryotic expression vector, pcDNA3.1. The recombinant vector was subsequently transfected into COS7 cells using a liposome transfection reagent. The recombinant protein was instantaneously expressed by the transfected cells, as detected by immunohistochemistry, and the recombinant pcDNA-VZV gE plasmid was subsequently used to immunize mice. Tissue expression levels were analyzed by reverse transcription-PCR. In addition, the levels of serum antibodies and spleen lymphocyte proliferation activity were investigated. The amplified target gene included the full-length gE gene (~2.7 kb), and the recombinant expression vector induced gE expression in COS7 cells. In addition, the expression plasmid induced sustained expression in vivo following immunization of mice. Furthermore, the plasmid was capable of inducing specific antibody production and effectively stimulating T cell proliferation. Effective humoral and cellular immunity was triggered in the mice immunized with the VZV gE eukaryotic expression vector. The results of the present study laid the foundation for future research into a VZV DNA vaccine.

11.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 5): m120-1, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25995894

RESUMO

In the title polymeric complex, {[Zn(C24H22N6O2)(H2O)4](NO3)2·2H2O} n , the Zn(II) cation, located about a twofold rotation axis, is coordinated by two imidazole groups and four water mol-ecules in a distorted N2O4 octa-hedral geometry; among the four coordinate water mol-ecules, two are located on the same twofold rotation axis. The 1,4-bis-[4-(1H-imidazol-1-yl)benzo-yl]piperazine] ligand is centro-symmetric, with the centroid of the piperazine ring located on an inversion center, and bridges the Zn(II) cations, forming polymeric chains propagating along [201]. In the crystal, O-H⋯O and weak C-H⋯O hydrogen bonds link the polymeric chains, nitrate anions and solvent water mol-ecules into a three-dimensional supra-molecular architecture. A short O⋯O contact of 2.823 (13) Šis observed between neighboring nitrate anions.

12.
Nucl Med Biol ; 38(4): 501-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21531287

RESUMO

INTRODUCTION: Nitroimidazole (azomycin) derivatives labeled with radioisotopes have been developed as cancer imaging and radiotherapeutic agents based on the oncological hypoxic mechanism. By attaching nitroimidazole core with different functional groups, we synthesized new nitroimidazole derivatives and evaluated their potentiality as tumor imaging agents. METHODS: Starting with commercially available 2-nitroimidazole, 2-fluoro-N-(2-(2-nitro-1H-imidazol-1-yl)ethyl)acetamide (NEFA, [(19)F]7) and 2-(2-methyl-5-nitro-1H-imidazol-1-yl)ethyl 2-fluoroacetate (NEFT, [(19)F]8), as well as radiolabeling precursors, the bromo-substituted analogs were quickly synthesized through a three-step synthetic pathway. The precursors were radiolabeled with [(18)F]F(-)/18-crown-6/KHCO(3) in dimethyl sulfoxide at 90°C for 10 min followed by purification with an Oasis HLB cartridge. Biodistribution studies were carried out in EMT-6 tumor-bearing mice. The uptake (%ID/g) in tumors and normal tissues were measured at 30 min postinjection. Liquid chromatography-electrospray ionization mass spectrometry (LC/MS) was used to distinguish metabolites from parent drugs in urine and plasma of rat injected with "cold" NEFA ([(19)F]7) and NEFT ([(19)F]8). RESULTS: Two radiotracers, [(18)F]NEFA ([(18)F]7) and [(18)F]NEFT ([(18)F]8), were prepared with average yields of 6%-7% and 9%-10% (not decay corrected). Radiochemical purity for both tracers was >95% as determined by HPLC. Biodistribution studies in EMT-6 tumor-bearing mice indicated that the tumor to blood and tumor to liver ratios of both [(18)F]7 (0.96, 0.61) and [(18)F]8 (0.98, 1.10) at 30 min were higher than those observed for [(18)F]FMISO (1) (0.91, 0.59), a well-investigated azomycin-type hypoxia radiotracer. Liquid chromatography-electrospray ionization mass spectrometry analysis demonstrated that fluoroacetate was the main in vivo metabolite for both NEFA ([(19)F]7) and NEFT ([(19)F]8). CONCLUSIONS: In this research, two new fluorine-18 labeled 2-nitroimidazole derivatives, [(18)F]7 and [(18)F]8, both of which containing in vivo hydrolyzable group, were successfully prepared. Further biological evaluations are warranted to investigate their potential as PET radioligands for imaging tumor.


Assuntos
Imidazóis/síntese química , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Animais , Imidazóis/química , Imidazóis/farmacocinética , Marcação por Isótopo , Ligantes , Camundongos , Neoplasias/metabolismo , Ratos
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