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1.
Org Lett ; 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33577339

RESUMO

The first fully connected aromatic carbaporphyrin dimer (6) and its bis-Pd complex (6-Pd2) that bear a rigid naphthalene motif as an internal strap were synthesized. These dimers consisted of two aromatic carbaporphyrins that shared a naphthalene motif. The π-electron conjugation of the obtained macrocycles was proposed to have two separated local 22 π-electron pathways and a 34 π-electron pathway. Their weak aromaticity was fully supported by 1H NMR spectroscopy, NICS values, ACID calculations, and ICSS plots.

2.
Acta Neurochir (Wien) ; 163(5): 1371-1381, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33404876

RESUMO

BACKGROUND: Primary decompressive craniectomy (DC) is considered for traumatic brain injury (TBI) patients with clinical deterioration, presenting large amounts of high-density lesions on computed tomography (CT). Postoperative CT findings may be suitable for prognostic evaluation. This study evaluated the radiographic predictors of clinical outcome and survival using pre- and postoperative CT scans of such patients. METHODS: We enrolled 150 patients with moderate to severe TBI who underwent primary DC. They were divided into two groups based on the 6-month postoperative Glasgow Outcome Scale Extended scores (1-4, unfavorable; 5-8, favorable). Radiographic parameters, including hemorrhage type, location, presence of skull fracture, midline shifting, hemispheric diameter, effacement of cisterns, parenchymal hypodensity, and craniectomy size, were reviewed. Stepwise logistic regression analysis was used to identify the prognostic factors of clinical outcome and 6-month mortality. RESULTS: Multivariable logistic regression analysis revealed that age (odds ratio [OR] = 1.09; 95% confidence interval [CI] 1.032-1.151; p = 0.002), postoperative low density (OR = 12.58; 95% CI 1.247-126.829; p = 0.032), and postoperative effacement of the ambient cistern (OR = 14.52; 95% CI 2.234-94.351; p = 0.005) and the crural cistern (OR = 4.90; 95% CI 1.359-17.678; p = 0.015) were associated with unfavorable outcomes. Postoperative effacement of the crural cistern was the strongest predictor of 6-month mortality (OR = 8.93; 95% CI 2.747-29.054; p = 0.000). CONCLUSIONS: Hemispheric hypodensity and effacement of the crural and ambient cisterns on postoperative CT after primary DC seems to associate with poor outcome in patients with TBI.

3.
Environ Monit Assess ; 192(2): 81, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31897611

RESUMO

Ecological quality (EcoQ) status of the Southwest and West coasts of South Korea was evaluated within the "National Investigation of Marine Ecosystems in Korea" in the 2015. In particular, the study dealt to assess the ecological quality of the sediments using free-living nematode communities. A total of 149 species were found in the study area, and Daptonema, Sabatieria, Parodontophora, Sphaerolaimus, and Viscosia were found as dominant genera. Statistical analysis of both environmental and faunal parameters showed an increasing human pressure from Western to Southern coasts. The community structure changed with the environmental features of the study area and allowed the detection of a suite of possible nematode indicators that might be used in monitoring studies. In particular, Dorylaimopsis spp. appeared heavy metal and organic matter resistant taxa, Sabatieria an eutrophication resistant genus, while Paracanthonchus and Neotonchus as heavy metal and organic matter sensitive genera. The principal component analysis (PCA) results showed a clear negative correlation between maturity index and both heavy metal and organic matter increasing, while diversity indices did not appear to be significantly influenced by them. Appling the thresholds of the synthetic nematode indices, the EcoQ of the study area was assessed as poor to moderate.


Assuntos
Ecossistema , Monitoramento Ambiental/métodos , Nematoides/fisiologia , Poluição da Água/análise , Animais , Ecologia , Eutrofização , Sedimentos Geológicos/química , Atividades Humanas , Metais Pesados , República da Coreia
4.
Org Lett ; 21(24): 10085-10089, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31808700

RESUMO

The first tolan derivative-based viscosity sensor (5d) has been synthesized, and its fluorescence intensity and lifetime increase when the viscosity of the solvent increases in methanol-glycerol mixtures. Phthalide (5d) was selected among structurally diverse tolan derivatives through systematic modifications of a simple tolan. To test 5d as a viscosity sensor, fluorescence lifetime imaging (FLIM) images of HeLa cells were obtained upon treatment with 5 µM of 5d to map the viscosity of the HeLa cells.

5.
Chemistry ; 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29740892

RESUMO

Allyliporphyrin is a carbaporphyrin that has replaced one pyrrole with an allyl group. Dynamic behavior (bond rotation) was observed by variable temperature 1 H NMR and 2D-NOESY NMR spectroscopy and theoretically examined by DFT calculations. These studies revealed that well-defined bond rotation was first observed in the limited space of the carbaporphyrin from 2 through cis-2 and the calculated rotational barrier was low enough, with the relative energy level of cis-2 only 0.65 kcal mol-1 higher than 2. The synthesized allyliporphyrin (2) is a strongly aromatic macrocycle as indicated by the chemical shifts of its inner NH and CH signals. However, its palladium complex displayed reduced aromaticity due to the tilted thiophene of Pd-2.

6.
Angew Chem Int Ed Engl ; 56(51): 16247-16251, 2017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29098755

RESUMO

An anthracene-containing meso-fused carbaporphyrin, which has extended π-conjugation pathways as compared to the corresponding naphthalene-containing carbaporphyrin, has been synthesized. The weak global aromaticity of the anthriporphyrin also allowed its use as the diene for a Diels-Alder reaction with dimethyl acetylenedicarboxylate (DMAD). The resulting phlorin contains an interesting bicyclic structure. Moreover, to the best of our knowledge, this phlorin is the first Diels-Alder adduct of a diene forming part of the global π-conjugation pathway of an aromatic porphyrinoid.

7.
Chem Commun (Camb) ; 53(83): 11414-11417, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28975165

RESUMO

A tolan derivative was synthesized as a fluorescent and cooperative ion pair receptor. As both Na+ and HSO4- ions were complexed to the receptor, only substantial fluorescence was quenched. Thus, it also acts as a logic AND gate.

8.
Chem Commun (Camb) ; 52(71): 10759-62, 2016 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-27510469

RESUMO

Hg(ii)-mediated hydration reactions of unsymmetrical quinoline type tolans were studied. The observed accelerated reactions of the tolans rely on the additional binding motifs of the tolan, as supported by the X-ray structure of the macrocycle (2b). The analyte-specific reaction allows us to detect Hg(ii) in buffered media.

9.
Zootaxa ; 4098(2): 333-57, 2016 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-27394589

RESUMO

One new and one known species of the family Comesomatidae Filiepjev, 1918 were collected from marine sediments in the East Sea, Korea. Cervonema donghaensis sp. nov. is related to C. proximamphidum Tchesunov, 2000 and C. chilensis Chen & Vincx, 2000 but differs from them by the presence of the gubernaculum and by having outer labial setae and cephalic setae of unequal length. It differs from C. proximamphidum by having a rather shorter tail and the shape of the posterior widening of the pharynx, which has distinct muscular striation. Cervonema donghaensis sp. nov. differs from C. chilensis in body length, higher de Man's ratio c, and having a shorter cylindrical portion of the tail. Cervonema deltensis Hope & Zhang 1995 is considered as a junior synonym of C. tenuicauda (Schuurmans Stekhoven, 1950) Wieser, 1954. Specimens of Laimella filipjevi Jensen, 1979 from East Sea, Korea largely agree with the original description of Jensen (1979) of nematodes from the Western Baltic Sea, except for slight differences in length of cephalic setae and spicules. It also coincides well with the redescription of L. filipjevi by Tchesunov (2000) based on specimens from the White Sea. Pictorial keys for the identification of valid species in the genera Cervonema Wieser, 1954 and Laimella Cobb, 1920 are given.


Assuntos
Adenofórios/classificação , Adenofórios/anatomia & histologia , Adenofórios/crescimento & desenvolvimento , Adenofórios/isolamento & purificação , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Sedimentos Geológicos/parasitologia , Masculino , Oceanos e Mares , Tamanho do Órgão , República da Coreia
10.
J Am Chem Soc ; 138(15): 4992-5, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-26906064

RESUMO

The first synthesis of meso-fused carbaporphyrin via a premodification method was accomplished by substituting two pyrrole moieties and one meso-carbon with 2-(naphthalen-1-yl)thiophene. The obtained global π-conjugation pathway of the macrocycle noticeably disturbs the 10π local aromaticity of naphthalene, and its aromatic nature was supported by NMR spectroscopy together with nucleus-independent chemical shift, anisotropy of the induced current density, and harmonic oscillator stabilization energy calculations. In addition, the meso-fused carbaporphyrin also allowed the formation of a square planar Pd(II) complex.

11.
Org Lett ; 17(24): 6222-5, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26633286

RESUMO

Conformationally locked tetrasubstituted tolans were synthesized by introducing a tether on the tolan. To demonstrate the utilities of these motifs, a ß-hairpin structure (15) was synthesized, and its additional stabilizing effects were evaluated. Moreover, the photophysical properties of cyclic tolans and their ß-sheet structure were investigated. The fluorescence quantum yield of cyclic tolan 12 is >1000 times stronger than its congener 1 in CH3CN.


Assuntos
Oligopeptídeos/química , Estrutura Secundária de Proteína , Acetileno/análogos & derivados , Acetileno/química , Cristalografia por Raios X , Fluorescência , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
12.
Chem Commun (Camb) ; 51(45): 9339-42, 2015 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-25959222

RESUMO

Cl(-) transporters that bear a terminal ethynyl group were synthesized; they consist of non-pyrrolic hydrogen bond motifs such as phenolic OH, amide NH, and triazole CH. The ethynyl group of these non-pyrrolic analogs plays an important role in chloride efflux and they exhibit no significant cytotoxic activity.


Assuntos
Acetileno/análogos & derivados , Modelos Biológicos , Acetileno/química , Transporte de Íons , Estrutura Molecular , Transportadores de Ânions Orgânicos/síntese química , Transportadores de Ânions Orgânicos/química
13.
Zootaxa ; 3785: 419-37, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24872235

RESUMO

Two new species of the family Enchelidiidae Filipjev, 1918 were collected from marine sediments near Maemul Island in South Korea: a new species of Abelbolla Huang & Zhang, 2004 and a new species of Ledovitia Filipjev, 1927. Abelbolla maemulensis sp. nov. is characterized by its small size (1,493 × 38 µm, body length × maximum body diameter); the presence of a circular amphid; the gubernacular apophysis with swollen distal tip; and the complex structure of the gubernaculum. It is close to Abelbolla huanghaiensis Huang & Zhang, 2004, but differs by the structure of gubernacular apophysis and body length (1,493 vs 2,303 µm). Ledovitia brevis sp. nov. can be separated from its congeners by its small size of body, the length of gubernacular apophysis, and the length of the spicules. It is close to Ledovitia pharetrata Wieser, 1953a, but differs by the length of the body (1,699 vs 2,640 µm) and the spicules (40 vs 100 µm).


Assuntos
Nematoides/anatomia & histologia , Nematoides/classificação , Animais , Demografia , Feminino , Ilhas , Masculino , Nematoides/fisiologia , República da Coreia , Especificidade da Espécie
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