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1.
Nat Commun ; 8(1): 100, 2017 07 24.
Article in English | MEDLINE | ID: mdl-28740107

ABSTRACT

Photochromic molecules have shown much promise as molecular components of stimuli-responsive materials, but despite recent achievements in various photoresponsive materials, quantitative conversion in photochemical reactions in solids is hampered by the lack of intrinsic structural flexibility available to release stress and strain upon photochemical events. This issue remains one of the challenges in developing solid-state photoresponsive materials. Here, we report a strategy to realize photoresponsive crystalline materials showing quantitative reversible photochemical reactions upon ultraviolet and visible light irradiation by introducing structural flexibility into crystalline porous frameworks with a twofold interpenetration composed of a diarylethene-based ligand. The structural flexibility of the porous framework enables highly efficient photochemical electrocyclization in a single-crystal-to-single-crystal manner. CO2 sorption on the porous crystal at 195 K is reversibly modulated by light irradiation, and coincident X-ray powder diffraction/sorption measurements clearly demonstrate the flexible nature of the twofold interpenetrated frameworks.Organizing photochromic molecules into 3D networks is a key strategy to access photoresponsive materials, but framework rigidity typically limits conversion efficiency. Here, the authors exploit a flexible metal-organic framework to achieve quantitative and reversible photoisomerization in a porous crystalline solid.

2.
Nanoscale ; 7(45): 18923-7, 2015 Dec 07.
Article in English | MEDLINE | ID: mdl-26525992

ABSTRACT

Porphyrin-based isostructural porous organic networks have been synthesized by varying the central metal atoms to cobalt, nickel and copper. Their selectivities for CO2 capture over N2 and Ar are found to be enhanced as the heats of adsorption for CO2 are increased in the order of Co, Ni and Cu, while the pore structures are well maintained.

3.
J Pharmacopuncture ; 18(3): 19-31, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26388999

ABSTRACT

OBJECTIVES: Correlations of the levels of the nonspecific inflammatory markers C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) and of the coagulation marker fibrinogen with the treatment period of wheel balanced cancer therapy were determined. METHODS: Electronic charts of stage IV cancer patients hospitalized from February 1, 2008, to November 30, 2013, were reviewed retrospectively. Patients whose laboratory follow-up tests included at least two data points for at least one marker were included. Patients receiving chemotherapy or radiotherapy or having Eastern Cooperative Oncology Group (ECOG) levels exceeding 2 were excluded. Correlations of the markers with the length of treatment for treatment periods ≥ 21 and ≤ 20 days were determined by gender and whether or not surgery had been performed. RESULTS: Analyses of the CRP and the ESR revealed a higher proportion of patients with stable marker levels than with increased or decreased levels. Also, only the ESR in female and the CRP in male groups had higher proportions of patients with stable marker levels than with increased or decreased levels. The ≥ 21 day group had a higher proportion of patients with stable CRP and ESR levels than the ≤ 20 day group. Only the ESR in female and the CRP in male groups had higher proportions of patients with stable marker levels in the ≥ 21 day than in the ≤ 20 day group. In addition, only the CRP in the surgery group and the ESR in the non-surgery group had higher proportions of patients with stable marker levels in the ≥ 21 day group than in the ≤ 20 day group. CONCLUSION: For stage IV cancer patients at hospitals that offer Korean medicine, more than 21 days of long-term wheel balanced cancer therapy (WBCT) should help maintain the CRP and the ESR levels and should have a favorable effect on the survival rate.

4.
Sci Rep ; 5: 12045, 2015 Jul 09.
Article in English | MEDLINE | ID: mdl-26155988

ABSTRACT

Although structures with the single functional constructions and micropores were demonstrated to capture many different molecules such as carbon dioxide, methane, and hydrogen with high capacities at low temperatures, their feeble interactions still limit practical applications at room temperature. Herein, we report in-situ growth observation of hierarchical pores in pomegranate metal-organic frameworks (pmg-MOFs) and their self-sequestering storage mechanism, not observed for pristine MOFs. Direct observation of hierarchical pores inside the pmg-MOF was evident by in-situ growth X-ray measurements while self-sequestering storage mechanism was revealed by in-situ gas sorption X-ray analysis and molecular dynamics simulations. The results show that meso/macropores are created at the early stage of crystal growth and then enclosed by micropore crystalline shells, where hierarchical pores are networking under self-sequestering mechanism to give enhanced gas storage. This pmg-MOF gives higher CO2 (39%) and CH4 (14%) storage capacity than pristine MOF at room temperature, in addition to fast kinetics with robust capacity retention during gas sorption cycles, thus giving the clue to control dynamic behaviors of gas adsorption.

5.
Chem Commun (Camb) ; 50(74): 10861-3, 2014 Sep 25.
Article in English | MEDLINE | ID: mdl-25089888

ABSTRACT

A perfluorobutyl-functionalized two-dimensional porous coordination polymer (PCP), {[Cu(bpbtp)(L)(DMF)]·(DMF)}n (H2bpbtp = 2,5-bis(perfluorobutyl)terephthalic acid, L = 2,5-bis(perfluorobutyl)-1,4-bis(4-pyridyl)benzene, DMF = N,N-dimethylformamide) has been synthesized and structurally characterized. The pore surface of the PCP is decorated with pendant perfluorobutyl groups which fabricate a densely fluorinated nanospace resulting in unique gas sorption properties.

6.
Korean J Anesthesiol ; 66(5): 392-7, 2014 May.
Article in English | MEDLINE | ID: mdl-24910733

ABSTRACT

Peripartum cardiomyopathy is a rare form of cardiomyopathy that is associated with significant mortality. It can cause a cardiac arrest during cesarean section even though the patient does not have any previous symptom and sign. The most important thing of anesthesia in this patient is an optimization of hemodynamic and respiratory status. We report the successful general anesthesia using of extracorporeal membrane oxygenation for cesarean section in a 34-year-old woman with fulminant peripartum cardiomyopathy.

7.
J Am Chem Soc ; 136(21): 7543-6, 2014 May 28.
Article in English | MEDLINE | ID: mdl-24816302

ABSTRACT

A porous coordination polymer (PCP) has been synthesized employing an organic ligand in which a stable free radical, isoindoline nitroxide, is incorporated. The crystalline PCP possesses one-dimensional channels decorated with the nitroxyl catalytic sites. When O2 gas or air was used as the oxidant, this PCP was verified to be an efficient, recyclable, and widely applicable catalyst for selective oxidation of various alcohols to the corresponding aldehydes or ketones.

8.
Chem Commun (Camb) ; 50(9): 1144-6, 2014 Feb 04.
Article in English | MEDLINE | ID: mdl-24322717

ABSTRACT

Three new sulfonated porous coordination polymers (PCPs)/metal-organic frameworks (MOFs) have been synthesized using solvothermal methods. These PCPs possess porous structures with non-coordinating sulfonic acid groups or sulfonate with dimethyl ammonium cations and exhibit high proton conductivity at a low humidity of 60% RH (relative humidity) at ambient temperature.

9.
J Pharmacopuncture ; 17(4): 66-9, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25780722

ABSTRACT

OBJECTIVES: Treating complex regional pain syndrome (CRPS) is difficult because it still does not have a recommended therapy. A 29-year-old man was diagnosed with CRPS after surgery on his 4(th) and 5(th) left toes 7 years ago. Though he had undergone diverse pain treatment, the symptoms persisted, so he visited Dunsan Korean Medicine Hospital of Daejeon University. This case report presents results on the effect of bee venom pharmacopuncture in treating patient with CRPS. METHODS: Bee venom pharmacopuncture (BVP), 0.15 to 0.4 mL dosage, was administered at GB43. The treatment was applied each week for a total 14 times. The symptoms were evaluated using a numeric rating scale (NRS) and the dosage of pain medicine. RESULTS: On the first visit, he was taking an anticonvulsant, a trycyclic antidepressant, and an analgesic. On the NRS the worst pain in the toes received a score of 8. He also complained of severe pain and hypersensitivity when the 4(th) and the 5(th) toes were touched just slightly. Other complaint included dyspepsia, rash, and depression. After treatment, on the NRS, the score for toe pain was 0, and he no longer needed to take pain medication. During the 4-months follow-up period, he has remained without pain; neither have additional symptoms appeared nor adverse events occurred. CONCLUSION: BVP may have potential benefits for treating patients with CRPS.

10.
Inorg Chem ; 52(19): 10735-7, 2013 Oct 07.
Article in English | MEDLINE | ID: mdl-24016100

ABSTRACT

Herein, we report new porous coordination polymers (PCPs) via a facile synthetic approach called "in situ generation of functionality in the ligand". Upon a synthetic process of PCPs, a neutral (-CH2OH) or a cationic functionality (-CH2-[4,4'-bipyridine](+)) was generated on a isophthalate ligand from a reactive haloalkane (-CH2Br) moiety, affording two new PCPs. The PCPs have two-dimensional layered structures with large potential solvent-accessible voids for CO2 adsorption.

11.
Chem Commun (Camb) ; 48(89): 11002-4, 2012 Nov 18.
Article in English | MEDLINE | ID: mdl-23037786

ABSTRACT

We report a new recipe to synthesize heterogeneous catalyst arrays using the space specificity of an embodied micelle. Also, SEM, AFM, STEM, and TXRF analyses prove that these catalysts are of exposed core-shell types. Furthermore, their structures were found to allow the design of a high performance photocatalyst for water splitting.

12.
Chem Commun (Camb) ; 48(3): 422-4, 2012 Jan 11.
Article in English | MEDLINE | ID: mdl-22075534

ABSTRACT

We report a facile route to synthesize size tunable Fe(3)O(4) nanoparticles (NPs)-carbon nitride nanotube (CNNT) hybrids. These hybrids showing the water-soluble property are proven to exhibit ultra high peroxidase mimetic activity compared to those of pure NPs, where a colorless peroxidase substrate 3,3,5,5-tetramethylbenzidine changes by H(2)O(2) to its blue colored oxidized state.


Subject(s)
Ferrosoferric Oxide/chemistry , Magnetics , Nanotubes, Carbon/chemistry , Nitriles/chemistry , Benzidines/chemistry , Catalysis , Hydrogen Peroxide/chemistry , Oxidation-Reduction , Peroxidase/metabolism
13.
J Am Chem Soc ; 133(31): 11920-3, 2011 Aug 10.
Article in English | MEDLINE | ID: mdl-21749096

ABSTRACT

Generally, crystals of synthetic porous materials such as metal-organic frameworks (MOFs) are commonly made up from one kind of repeating pore structure which predominates the whole material. Surprisingly, little is known about how to introduce heterogeneously arranged pores within a crystal of homogeneous pores without losing the crystalline nature of the material. Here, we outline a strategy for producing crystals of MOF-5 in which a system of meso- and macropores either permeates the whole crystal to make sponge-like crystals or is entirely enclosed by a thick crystalline microporous MOF-5 sheath to make pomegranate-like crystals. These new forms of crystals represent a new class of materials in which micro-, meso-, and macroporosity are juxtaposed and are directly linked unique arrangements known to be useful in natural systems but heretofore unknown in synthetic crystals.


Subject(s)
Organometallic Compounds/chemistry , Crystallization , Organometallic Compounds/chemical synthesis , Particle Size , Porosity , Powder Diffraction , Surface Properties
14.
Microbiology (Reading) ; 155(Pt 5): 1726-1737, 2009 May.
Article in English | MEDLINE | ID: mdl-19372160

ABSTRACT

In this study we isolated over 250 lactic acid bacteria (LAB) candidates from fruit, flowers, vegetables and a fermented food to generate an LAB library. One strain, designated 925A, isolated from kimchi (a traditional Korean fermented dish made from Chinese cabbage) produced a novel type of bacteriocin, brevicin 925A, which is effective against certain LAB, including strains of Lactobacillus, Enterococcus, Streptococcus, Bacillus and Listeria. Strain 925A, identified as Lactobacillus brevis, harboured at least four plasmids and we determined the entire nucleotide sequence of each one. The four plasmids were designated pLB925A01-04, and have molecular sizes of 1815, 3524, 8881 and 65 037 bp, respectively. We obtained bacteriocin non-producing derivatives by treatment of strain 925A with novobiocin. All of these derivatives, which were susceptible to their own antibacterial product, lost the largest plasmid, pLB925A04, suggesting that the genes for bacteriocin biosynthesis (breB and breC) and immunity (breE) are located on pLB925A04. The partial amino acid sequence of purified brevicin 925A and sequence analysis of pLB925A04 showed that breB is the structural gene for brevicin 925A. We constructed a shuttle vector (pLES003, 6134 bp) that can replicate in both Escherichia coli and LAB such as Lactobacillus plantarum, Lb. brevis, Lactobacillus helveticus, Lactobacillus hilgardii and Enterococcus hirae. To determine the function of gene breE, which displays no significant similarity to any other sequences in the blast search database, the gene was inserted into pLES003. A pLB925A04-cured derivative transformed with pLES003 carrying breE acquired immunity to brevicin 925A, suggesting that breE encodes an immunity protein.


Subject(s)
Bacteria/genetics , Bacteriocins/genetics , Food Microbiology , Gene Expression , Genetic Vectors/genetics , Lactobacillus/genetics , Plasmids/genetics , Bacteria/drug effects , Bacteria/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Bacteriocins/metabolism , Bacteriocins/pharmacology , Base Sequence , Escherichia coli/genetics , Escherichia coli/metabolism , Lactic Acid/metabolism , Lactobacillus/isolation & purification , Lactobacillus/metabolism , Molecular Sequence Data
15.
Biochem Biophys Res Commun ; 378(3): 574-8, 2009 Jan 16.
Article in English | MEDLINE | ID: mdl-19061861

ABSTRACT

Bacteriocin-producing lactic acid bacteria (LAB) possess a self-protection factor, which is generally called an immunity protein. In this study, we determine the crystal structure of an immunity protein, designated Mun-im, which was classified into subgroup B immunity proteins for class IIa bacteriocins. The Mun-im protein takes a left-turning antiparallel four-helix bundle structure with the flexible N- and C-terminal parts. Although the amino acid sequences of the subgroup B immunity proteins are distinguished from those of the subgroup A, the core structure of Mun-im is well-superimposed with that of the subgroup A immunity protein, EntA-im, and the C-terminus of both proteins is flexible. However, the C-terminus of Mun-im is obviously shorter than that of the subgroup A. We found through mutagenic study of Mun-im that the C-terminus and the K86 residue on the helix 4 in the immunity protein molecule are important for expression of the immunity activity on the subgroup B immunity proteins.


Subject(s)
Bacterial Proteins/chemistry , Bacteriocins/immunology , Enterococcus/immunology , Amino Acid Sequence , Bacterial Proteins/genetics , Bacterial Proteins/immunology , Crystallography, X-Ray , DNA Mutational Analysis , Enterococcus/genetics , Enterococcus/metabolism , Molecular Sequence Data , Protein Conformation
16.
J Agric Food Chem ; 54(26): 9827-33, 2006 Dec 27.
Article in English | MEDLINE | ID: mdl-17177508

ABSTRACT

The present study found that the n-hexane extract of freeze-dried sake lees inhibits tyrosinase activity and showed that the constituents isolated from the n-hexane extract are the mixture of triacylglycerols. The inhibitory effects of triolein and trilinolein found as the triacylglycerols were examined using tyrosinases from mushroom and Streptomyces castaneoglobisporus. The IC50 values of the triacylglycerol mixture for the oxidase activity on mushroom and Streptomyces tyrosinases were 20 and 0.14 microg/mL, respectively. The IC50 values of trilinolein for the oxidase activity on mushroom and Streptomyces tyrosinases were 8.4 and 0.1 microM, respectively. However, the inhibitory effect of triolein (IC50=30 microM) was lower than that of trilinolein, even when the Streptomyces tyrosinase was used for the assay. Kinetic analyses indicate that both trilinolein and triolein inhibit the tyrosinase activity noncompetitively. When transformed with a plasmid carrying the Streptomyces tyrosinase gene, the melanin-synthesizing ability of the transformed Escherichia coli host was dose-dependently interfered with by trilinolein.


Subject(s)
Alcoholic Beverages/analysis , Enzyme Inhibitors/analysis , Monophenol Monooxygenase/antagonists & inhibitors , Agaricales/enzymology , Enzyme Inhibitors/isolation & purification , Escherichia coli/genetics , Food Handling , Freeze Drying , Kinetics , Melanins/biosynthesis , Monophenol Monooxygenase/genetics , Monophenol Monooxygenase/metabolism , Recombinant Proteins/metabolism , Streptomyces/enzymology , Triglycerides/pharmacology
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