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1.
Korean J Gastroenterol ; 75(1): 46-49, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31986573

RESUMO

Intussusception is a medical condition, in which a proximal part of the intestine folds into the distal intestine. Adult intussusceptions are rare and account for approximately 5% of all cases of intussusceptions. The anatomical leading points include tumors, diverticulums, polyps, and strictures in 80-90% of adult intussusceptions, and 65% of colon intussusceptions and 30% of small bowel intussusceptions originate from malignant tumors. Treatments for adult intussusception have not been established, but most cases require surgical treatment. The gastrointestinal tract is the most common extranodal site for non-Hodgkin lymphoma. The symptoms are mostly non-specific, but they rarely lead to complications, such as bleeding, perforation, and intussusception. Furthermore, few cases of primary gastrointestinal lymphomas causing intussusception have been reported. This paper reports a case of small bowel diffuse large B cell lymphoma that caused ileocolic intussusception in a 69-year-old woman with no medical history. She underwent a small bowel resection and received six cycles of adjuvant chemotherapy with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone. Since then, she has been in complete remission.

2.
Gastroenterology ; 158(3): 482-484, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31560905
4.
Chem Asian J ; 15(2): 253-265, 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31823512

RESUMO

Conversion of carbon dioxide (CO2 ) into value-added chemicals has attracted much attention because it can not only resolve global warming issues by reducing CO2 accumulation in the atmosphere, but also produce renewable hydrocarbon fuels that are important feedstocks for the chemical industry. Among the diverse approaches reported, CO2 reduction via electro- and photocatalytic methods is at the center of topics due to potential engineering of reaction performance through rational design of catalyst features. In this Minireview, we highlight recent strategies for designing nanoparticles to maximize the reaction efficiency and selectivity; from a materials viewpoint, these strategies can provide critical information to guide future research directions.

5.
Gastroenterol Res Pract ; 2019: 8425157, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687016

RESUMO

Background: Rectal neuroendocrine tumors (NETs) < 10 mm in diameter, limited to the submucosa without local or distant metastasis, can be treated endoscopically. Endoscopic mucosal resection with a ligation band device (EMR-L) and endoscopic submucosal dissection (ESD) have been employed to resect rectal NETs. We evaluated and compared the clinical outcomes of EMR-L and ESD for endoscopic resection of rectal NETs G1 < 10 mm in diameter. Methods: We conducted a retrospective study of 82 rectal NETs in 82 patients who underwent either EMR-L or ESD. Therapeutic outcomes (en bloc resection and complete resection rates), procedure time, and procedure-related adverse events were evaluated. Additionally, we measured the distance of the lateral and vertical margins from the border of the tumor in pathologic specimens and compared the resectability between EMR-L and ESD. Results: Sixty-six lesions were treated using EMR-L and 16 using ESD. En bloc resection was achieved in all patients. The complete resection rate with EMR-L was significantly higher than that with ESD (95.5% vs.75.0%, p = 0.025). The prevalence of vertical margin involvement was significantly higher in the ESD group than in the EMR-L group (12.5% vs. 0%, p = 0.036), and ESD was more time consuming than EMR-L (24.21 ± 12.18 vs. 7.05 ± 4.53 min, p < 0.001). The lateral and vertical margins were more distant in the EMR-L group than in the ESD group (lateral margin distance, 1661 ± 849 vs. 1514 ± 948 µm; vertical margin distance, 277 ± 308 vs. 202 ± 171 µm). Conclusions: EMR-L is more favorable for small rectal NETs with respect to therapeutic outcomes, procedure time, and technical difficulties. Additionally, EMR-L enables achievement of sufficient vertical margin distances.

6.
Medicine (Baltimore) ; 98(23): e15885, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31169696

RESUMO

Duodenal neuroendocrine tumors (NETs) are rare, and risk factors associated with lymph node (LN) metastasis are still not well defined. The aim of this study was to investigate risk factors of LN metastasis in duodenal NETs based on the final histopathologic results and clinical follow-up data.This study included a total of 44 duodenal NETs in 38 patients who underwent endoscopic or surgical resection between January 2008 and December 2015. Diagnosis of duodenal NETs was confirmed based on immunohistochemical staining of chromogranin A, synaptophysin, and CD56; the clinicopathologic records were collected at the time of the initial diagnosis of duodenal NETs.Most duodenal NETs were small (≤1 cm in 33 tumors), World Health Organization (WHO) grade G1 (in 32 tumors), limited to the mucosa and/or submucosa (in 40 tumors), and located at the duodenal bulb (in 32 tumors). Of 44 tumors, lymphovascular invasion was present in 4 (9.1%), and among 38 patients, LN metastasis was detected in 4 (10.5%). LN metastases were significantly associated with the non-bulb location, tumor size >10 mm, tumor invasion into the muscularis propria or deeper, WHO grade G2, and lymphovascular invasion. During the mean follow-up period of 54.5 months (range, 24-123 months), recurrence occurred in 1 patient.Non-bulb location, tumor size >10 mm, invasion beyond the submucosa, WHO grade G2, and lymphovascular invasion are risk factors of LN metastasis in duodenal NETs. These findings can help clinicians choose the appropriate therapeutic modality for duodenal NETs.


Assuntos
Neoplasias Duodenais/patologia , Metástase Linfática/patologia , Tumores Neuroendócrinos/patologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Fatores de Risco , Carga Tumoral
7.
J Am Chem Soc ; 141(17): 6986-6994, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30964296

RESUMO

For long-term storage of renewable energy, the electrochemical carbon dioxide reduction reaction (CO2RR) offers a promising option for converting electricity to permanent forms of chemical energy. In this work, we present highly selective ethylene production dependent upon the catalyst morphology using copper oxide nanoparticles. The branched CuO nanoparticles were synthesized and then deposited on conductive carbon materials. After activation, the major copper species changed to Cu+, and the resulting electrocatalyst exhibited a high Faradaic efficiency (FE) of ethylene reaching over 70% and a hydrogen FE of 30% without any byproducts in a neutral aqueous solution. The catalyst also showed high durability (up to 12 h) with the ethylene FE over 65%. Compared to cubic morphology, the initial branched copper oxide structure formed highly active domains with interfaces and junctions in-between during activation, which caused large surface area with high local pH leading to high selectivity and activity for ethylene production.

8.
Infect Chemother ; 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31668023

RESUMO

Neutropenic enterocolitis is a fatal enterocolitis occurring in neutropenic patients with immunocompromised diseases including hematologic malignancies. Gastrointestinal (GI) mucormycosis in hematologic malignancies has been rarely reported. Especially, in myelodysplastic syndrome (MDS), GI mucormycosis has never been reported. We report a case of GI mucormocysis manifesting as neutropenic enterocolitis in a patient with MDS.

9.
Health Commun ; 33(8): 1013-1019, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28622026

RESUMO

Do graphic pictorial health warnings (GPHWs) on cigarette packaging work better for some people than others? According to the Extended Parallel Process Model (EPPM), fear appeals should heighten positive change only if a person believes he or she is capable of change (i.e., self-efficacy). We exposed 242 smokers and 241 nonsmokers (aged 18-29) in the Republic of Korea to either a GPHW or a text-only warning in a between-subjects experiment. Results indicated that the GPHW increased intentions and motivations to quit smoking (for smokers) and intentions and motivations to not start smoking (for nonsmokers). However, these effects were moderated by self-efficacy related to quitting or not starting smoking. For smokers, a GPHW was especially effective in increasing desires and intentions to quit for people high in self-efficacy and high in self-esteem. However, for nonsmokers, a GPHW was effective only when self-efficacy was high, regardless of self-esteem level. For smokers and nonsmokers, results were mediated by heightened perceived health estimation. Implications for understanding the effectiveness of warning labels on cigarettes, for the introduction of GPHWs in the Republic of Korea, and for the Extended Parallel Process Model, are discussed.


Assuntos
não Fumantes/estatística & dados numéricos , Rotulagem de Produtos/métodos , Autoimagem , Autoeficácia , Fumantes/estatística & dados numéricos , Produtos do Tabaco/efeitos adversos , Adolescente , Adulto , Atitude Frente a Saúde , Feminino , Humanos , Intenção , Masculino , Motivação , República da Coreia , Abandono do Hábito de Fumar/psicologia , Prevenção do Hábito de Fumar , Adulto Jovem
10.
Motiv Emot ; 41(4): 478-491, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28757667

RESUMO

Although men typically hold favorable views of advertisements featuring female sexuality, from a Terror Management Theory perspective, this should be less the case when thoughts of human mortality are salient. Two experiments conducted in South Korea supported this hypothesis across a variety of products (e.g., perfume and vodka). Men became more negative towards advertisements featuring female sexuality, and had reduced purchase intentions for those products, after thinking about their own mortality. Study 2 found that these effects were mediated by heightened disgust. Mortality thoughts did not impact women in either study. These findings uniquely demonstrate that thoughts of death interact with female sex-appeal to influence men's consumer choices, and that disgust mediates these processes. Implications for the role of emotion, and cultural differences, in terror management, for attitudes toward female sexuality, and for marketing strategies are discussed.

11.
Chem Commun (Camb) ; 53(19): 2858-2861, 2017 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-28217781

RESUMO

Strongly emissive cuprous complexes containing a stable σ-SiH-Cu motif were prepared. These complexes serve as a proof of principle that σ-complexation can be utilized as a design principle for engineering responsive light emitting materials. Their excited state lifetimes were found to be long (∼20 µs) with high quantum yields (φ = 0.40-0.59).

12.
Lab Anim Res ; 32(2): 87-90, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27382376

RESUMO

The antibacterial activities of the essential oil of Eucalyptus globulus (EOEG) was determined against 7 fish pathogenic bacteria (Edwardsiella tarda, Streptococcus iniae, S. parauberis, Lactococcus garviae, Vibrio harveyi, V. ichthyoenteri and Photobacterium damselae) obtained from farmed olive flounder. The inhibitory activity was evaluated by three methods: Disc diffusion method, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). According to the disc diffusion test, as the concentration of EOEG (5-40 µg) rises, the inhibitory zone increases in size. Compared with amoxicillin, tetracycline and chloramphenicol, EOEG showed similar antibacterial activity. The MIC of EOEG ranged from 7.8 to 125 mg/mL and MBC values ranged from 62 to 250 mg/mL. These results show that EOEG has antimicrobial activity against all seven bacteria, but there was no marked difference between each genus. From these results, it is suggested that EOEG can be used as an antimicrobial agent against fish bacterial diseases in the fish industry.

13.
Tuberc Respir Dis (Seoul) ; 78(4): 419-22, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26508937

RESUMO

We presented a case of unusual endobronchial inflammatory polyps as a complication following endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in a patient with tuberculous lymphadenitis. EBUS-TBNA of the right hilar lymph node was performed in a 29-year-old, previously healthy man. The patient was confirmed with tuberculous lymphadenitis and received antituberculosis medication over the course of 6 months. Chest computed tomography, after 6 months of antituberculosis therapy following the EBUS-TBNA showed nodular bronchial wall thickening of the right main bronchus. Histological and microbiological examinations revealed inflammatory polyps. After 7 months, the inflammatory polyps regressed almost completely without need for removal.

14.
Plant Cell Environ ; 37(1): 101-12, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23668360

RESUMO

Natural variation in heading-date genes enables rice, a short-day (SD) plant, to flower early under long-day (LD) conditions at high latitudes. Through analysis of heading-date quantitative trait loci (QTL) with F7 recombinant inbred lines from the cross of early heading 'H143' and late heading 'Milyang23 (M23)', we found a minor-effect Early Heading3 (EH3) QTL in the Hd16 region on chromosome 3. We found that Early flowering1 (EL1), encoding casein kinase I (CKI), is likely to be responsible for the EH3/Hd16 QTL, because a missense mutation occurred in the highly conserved serine/threonine kinase domain of EL1 in H143. A different missense mutation was found in the EL1 kinase domain in Koshihikari. In vitro kinase assays revealed that EL1/CKI in H143 and Koshihikari are non-functional. In F7:9 heterogeneous inbred family-near isogenic lines (HNILs), HNIL(H143) flowered 13 days earlier than HNIL(M23) in LD, but not in SD, in which EL1 mainly acts as a LD-dependent flowering repressor, down-regulating Ehd1 expression. In the world rice collection, two types of non-functional EL1 variants were found in japonica rice generally cultivated at high latitudes. These results indicate that natural variation in EL1 contributes to early heading for rice adaptation to LD in temperate and cooler regions.


Assuntos
Caseína Quinase I/genética , Flores/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Variação Genética , Oryza/genética , Locos de Características Quantitativas/genética , Alelos , Caseína Quinase I/metabolismo , Mapeamento Cromossômico , Regulação para Baixo , Flores/genética , Flores/efeitos da radiação , Geografia , Endogamia , Mutação de Sentido Incorreto , Oryza/fisiologia , Oryza/efeitos da radiação , Fosforilação , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Temperatura
15.
Mol Plant ; 6(6): 1877-88, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23713079

RESUMO

Heading date and photoperiod sensitivity are fundamental traits that determine rice adaptation to a wide range of geographic environments. By quantitative trait locus (QTL) mapping and candidate gene analysis using whole-genome re-sequencing, we found that Oryza sativa Pseudo-Response Regulator37 (OsPRR37; hereafter PRR37) is responsible for the Early heading7-2 (EH7-2)/Heading date2 (Hd2) QTL which was identified from a cross of late-heading rice 'Milyang23 (M23)' and early-heading rice 'H143'. H143 contains a missense mutation of an invariantly conserved amino acid in the CCT (CONSTANS, CO-like, and TOC1) domain of PRR37 protein. In the world rice collection, different types of nonfunctional PRR37 alleles were found in many European and Asian rice cultivars. Notably, the japonica varieties harboring nonfunctional alleles of both Ghd7/Hd4 and PRR37/Hd2 flower extremely early under natural long-day conditions, and are adapted to the northernmost regions of rice cultivation, up to 53° N latitude. Genetic analysis revealed that the effects of PRR37 and Ghd7 alleles on heading date are additive, and PRR37 down-regulates Hd3a expression to suppress flowering under long-day conditions. Our results demonstrate that natural variations in PRR37/Hd2 and Ghd7/Hd4 have contributed to the expansion of rice cultivation to temperate and cooler regions.


Assuntos
Variação Genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Alelos , Mutação de Sentido Incorreto , Oryza/genética , Locos de Características Quantitativas
16.
Org Biomol Chem ; 7(20): 4225-32, 2009 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-19795061

RESUMO

A novel solvatochromic fluorescent molecule, 9,9-dibutyl-7-(dimethylamino)-2-fluorenesulfonate 2 was synthesized from 2-nitrofluorene in moderate yield. The fluorescence spectra of 2 and 7-(dimethylamino)-2-fluorenesulfonate 1 shift to shorter wavelengths as the polarity of the medium decreases. Both 1 and 2 bind to hydrophobic sites of human serum albumin (HSA). The apparent binding constants were determined by fluorescence titration to be 0.37 x 10(6) M(-1) for 1 and 2.2 x 10(6) M(-1) for 2. The energy of the Trp-214 fluorescence of HSA is transferred to the HSA-bound fluorophores with near 100% efficiency. The covalent bonding of acrylodan (AC) to Cys-34 has little effect on the binding affinity of 2 to HSA or fluorescent behavior of HSA-bound 2. Bound 2 also has little effect on the fluorescence of AC, but 2-->AC and Trp-214-->2-->AC resonance energy transfers were observed. Competitive binding between the fluorene compounds and other ligands such as 1-anilino-8-naphthalenesulfonate, aspirin, S-(+)-ibuprofen and phenylbutazone were also studied fluorometrically. The results indicated that the primary binding site of 2 to HSA is site II in domain IIIA, whereas 1 binds to site I in domain IIA, but a different region from the phenylbutazone binding site. Because of its large molar absorptivity, strong fluorescence, sensitivity to its environment, and high binding constant to HSA, 2 can be used successfully in the study of proteins and their binding properties.


Assuntos
Fluorenos/química , Fluorenos/metabolismo , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Albumina Sérica/metabolismo , 2-Naftilamina/análogos & derivados , 2-Naftilamina/metabolismo , Absorção , Ligação Competitiva , Biomimética , Fluorenos/síntese química , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/síntese química , Humanos , Ligantes , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Albumina Sérica/química , Solubilidade , Espectrofotometria Ultravioleta , Água/química
17.
J Fluoresc ; 17(4): 361-9, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17522966

RESUMO

A novel water-soluble solvatochromic molecule, 7-(dimethylamino)-2-fluorenesulfonate (2,7-DAFS), was prepared by a three-step reaction from 2-nitrofluorene in good overall yield. The pH and solvent effects on the UV-VIS absorption and fluorescence spectra of 2,7-DAFS have been studied. Protonation of the dimethylamino group switches the absorption from intramolecular charge-transfer (ICT) to pi --> pi* transition. The ground state pKa value of 2,7-DAFS was determined as 4.51. The fluorescence spectrum of the excited basic form, *(DAFS), shows a structureless single band with a large Stokes shift, whereas that of the acidic form, *((+)HDAFS), exhibits a structured band with a small Stokes shift. The emission intensities of the basic and acidic forms versus pH/Ho plots show stretched sigmoidal curves and indicate that (1) the rate of deprotonation of *((+)HDAFS) is comparable to the fluorescence decay of the species, and (2) the efficient proton-induced quenching of *(DAFS) fluorescence occurs. The pKa* was estimated as -1.7 from the fluorescence titration curve. The fluorescence maximum of *(DAFS) is blue-shifted as the polarity of solvent decreases. However, no clear dependency of the emission intensity and spectral half width, and thus fluorescence quantum yield, on the solvent polarity was revealed. It appears that the fluorescence sensitivity of 2,7-DAFS is 15 approximately 25 times greater than the sensitivity of a widely utilized fluorescent probe, 5-(dimethylamino)-1-naphthalenesulfonate. This higher sensitivity, together with the ease of derivatization, would provide the fluorene-based fluorescent molecules significant advantages for a variety of applications.


Assuntos
Alcanossulfonatos/química , Fluorenos/química , Corantes Fluorescentes/química , Alcanossulfonatos/síntese química , Fluorenos/síntese química , Fluorescência , Corantes Fluorescentes/síntese química , Concentração de Íons de Hidrogênio , Solventes , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Água
18.
J Phys Chem B ; 110(49): 24915-22, 2006 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-17149912

RESUMO

The kinetics of cyclodextrin (CD) inclusion complexation has been usually analyzed in terms of a one-step reaction or a consecutive two-step reaction involving intracomplex structural transformation as a second step. These schemes presume the inclusion of guest molecules through only one side of the CD cavity and the formation of unidirectional CD complexes. However, there has been increasing experimental evidence for the inclusion of guests through both sides of the CD cavity and the formation of orientational isomers for noncentrosymmetric guest molecules. This article presents a novel parallel reaction scheme for CD inclusion complexation, incorporating bidirectional inclusion and the formation of orientational isomers into the scheme. It is shown that the parallel reaction scheme gives the same concentration versus reaction time relationship as the consecutive two-step reaction scheme. The experimental methods for determining the microscopic directional rate constants are presented. The kinetic parameters of the two-step reaction scheme are expressed as functions of the directional rate constants. The ratios of orientational isomers of alpha-CD-based [2]-pseudorotaxanes and the microscopic directional rate constants of the threading and dethreading reactions are estimated from the reported thermodynamic and kinetics data obtained by using either the one-step or two-step reaction scheme. It is shown that the thermodynamic preference of an isomer over the other is mainly due to the slow dethreading rate of the isomer.

19.
J Org Chem ; 70(23): 9505-13, 2005 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-16268626

RESUMO

[Reaction: see text]. The self-inclusion behavior and induced circular dichroism (ICD) characteristics of two beta-cyclodextrin (beta-CD) derivatives, in which a 1-methyl-4,4'-bipyridinium (viologen) group is connected by an octamethylene chain to either the primary (2(2+)) or secondary (3(2+)) side of beta-CD, and of their reduced forms, are investigated. 1H NMR studies showed that 2(2+) forms an intramolecular self-inclusion complex with K(in) = 3.1 +/- 0.4, whereas 3(2+) forms a head-to-head type of dimer with K(D) = 65 +/- 10 M(-1) at 25 degrees C. 2(2+) and 3(2+) form [2]pseudorotaxanes with alpha-CD, with the secondary side of the alpha-CD facing the viologen moiety. The ICD characteristics of mono-6-[4-(1-methyl-4-pyridinio)-1-pyridinio]-beta-CD (1(2+)), 2(2+), 3(2+), and methyloctyl viologen-beta-CD complexes were obtained for the oxidized and reduced states of the viologen units. The results indicated dimer formation for 1 degrees , and intramolecular complexation for 2*+ and 2 degrees in which the reduced viologen units are outside the beta-CD cavity. The results also indicated intramolecular complexation for 3*+ and 3 degrees, but with reduced viologen units inside the cavity. This work provides unequivocal evidence of the preference of the secondary side of cyclodextrins for viologen groups, regardless of their oxidation states, and the dependence of ICD of the viologen chromophores on their location with respect to the CD cavity.

20.
Org Lett ; 6(26): 4869-72, 2004 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-15606087

RESUMO

[structure: see text] Capping the alpha-cyclodextrin (alpha-CD) complex of 1-(N-carbazole)-10-[4-(4-pyridinio)-1-pyridinio]decane with 3,5-dimethoxybenzyl bromide in DMF gives two isomeric [2]rotaxanes, 2a and 2b, while alpha-CD and 1-(N-carbazole)-10-[4-(1-methyl-4-pyridnino)-1-pyridinio]decane 3 in water form mostly a unidirectional [2]pseudorotaxane having the same alpha-CD orientation as 2b. Structures were elucidated from 1H NMR and circular dichroism spectra. The orientational specificity of alpha-CD in the 3/alpha-CD [2]pseudorotaxane is due to the slow dethreading rate of the 2b-type isomer.

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