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Enantioselectivity of helical aggregation is conventionally directed either by its homochiral ingredients or by introduction of chiral catalysis. The fundamental question, then, is whether helical aggregation that consists only of achiral components can obtain enantioselectivity in the absence of chiral catalysis. Here, by exploiting enantiospecific interaction due to chiral-induced spin selectivity (CISS) that has been known to work to enantio-separate a racemic mixture of chiral molecules, we demonstrate the enantioselectivity in the assembly of mesoscale helical supramolecules consisting of achiral cobalt phthalocyanines. The helical nature in our supramolecules is revealed to be mesoscopically incorporated by dislocation-induced discretized twists, unlike the case of chiral molecules whose chirality are determined microscopically by chemical bond. The relevance of CISS effect in the discretized helical supramolecules is further confirmed by the appearance of spin-polarized current through the system. These observations mean that the application of CISS-based enantioselectivity is no longer limited to systems with microscopic chirality but is expanded to the one with mesoscopic chirality.
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HYPOTHESIS: We have proposed a spreading-flow model of the solvent movement in a gel, which states that the solvent flows along the gel network segment much easier than in any other direction. An excess amount of the solvent component adsorbed on a flat solid surface in a gel will be transferred over the macroscopic gel network by the spreading-flow. Then, by measuring the concentration distribution of each solvent near the solid surface at the sub-millimeter scale, it should be possible to evaluate adsorption occurring on the nanometer scale. EXPERIMENTS: Confocal Raman microscopy was employed to map the concentration distributions of mixed solvents of p-xylene, mesitylene, and octanenitrile gelled by 12-hydroxystearic acid near the atomically flat mica surface. The measured concentration profiles were analyzed by the spreading-flow theory to construct adsorption isotherms. FINDINGS: Nearly all isotherms follow power laws with similar exponents, which is consistent with the van der Waals multilayer adsorption with weak adsorbate-adsorbent interactions. The present study demonstrates the concept of gel network amplification and its usefulness for probing nano-phenomena using macro-technology.
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A salen-type Schiff base Zn(II) complex included in human serum albumin (HSA) protein was examined by UV-Vis, circular dichroism (CD), and fluorescence (PL) spectra. The formation of the composite material was also estimated by a GOLD program of ligand-protein docking simulation. A composite cast film of HSA and Zn(II) complex was prepared, and the effects of the docking of the metal complex on the degradation of protein molecules by mid-infrared free electron laser (IR-FEL) were investigated. The optimum wavelengths of IR-FEL irradiation to be used were based on experimental FT-IR spectra and vibrational analysis. Using TD-DFT results with 6-31G(d,p) and B3LYP, the IR spectrum of Zn(II) complex could be reasonably assigned. The respective wavelengths were 1652 cm-1 (HSA amide I), 1537 cm-1 (HSA amide II), and 1622 cm-1 (Zn(II) complex C=N). Degradation of HSA based on FT-IR microscope (IRM) analysis and protein secondary structure analysis program (IR-SSE) revealed that the composite material was degraded more than pure HSA or Zn(II) complex; the inclusion of Zn(II) complex enhanced destabilization of folding of HSA.
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Complexos de Coordenação/metabolismo , Albumina Sérica Humana/metabolismo , Zinco/química , Sítios de Ligação , Complexos de Coordenação/química , Teoria da Densidade Funcional , Etilenodiaminas/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Secundária de Proteína , Bases de Schiff/química , Albumina Sérica Humana/química , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
An infrared free electron laser (IR-FEL) can decompose aggregated proteins by excitation of vibrational bands. In this study, we prepared hybrid materials of protein (human serum albumin; HSA) including several new Schiff base Zn(II) complexes incorporating amino acid (alanine and valine) or dipeptide (gly-gly) derivative moieties, which were synthesized and characterized with UV-vis, circular dichroism (CD), and IR spectra. Density functional theory (DFT) and time dependent DFT (TD-DFT) calculations were also performed to investigate vibrational modes of the Zn(II) complexes. An IR-FEL was used to irradiate HSA as well as hybrid materials of HSA-Zn(II) complexes at wavelengths corresponding to imine C=N, amide I, and amide II bands. Analysis of secondary structures suggested that including a Zn(II) complex into HSA led to the structural change of HSA, resulting in a more fragile structure than the original HSA. The result was one of the characteristic features of vibrational excitation of IR-FEL in contrast to electronic excitation by UV or visible light.
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Raios Infravermelhos , Lasers , Bases de Schiff/química , Albumina Sérica Humana/química , Zinco/química , HumanosRESUMO
BACKGROUND: Numerous studies have been conducted in many countries to identify the factors associated with readmission of patients with heart failure (HF). However, there have been no such studies utilizing a large-scale administrative database in Japan. This study aimed to establish the factors associated with 30-day readmission of patients with HF using a Japanese nationwide administrative database. METHODS: Data of the index admissions of 68,257 patients discharged from 1057 participating hospitals between April 1, 2012 and March 31, 2013 were analyzed. Patients were divided into the 30-day readmission group and no readmission group according to whether unplanned HF readmission occurred within 30 days after discharge. Study variables included age, sex, New York Heart Association functional class (NYHA) at admission, Charlson Comorbidity Index (CCI), length of stay in hospital (LOS), body mass index (BMI) at admission, hospital volume reflected by the number of cases hospitalized with HF, and medical treatment at discharge. RESULTS: The 30-day readmission and no readmission groups included 4479 and 63,778 patients, respectively. The independent factors associated with the increase in 30-day readmission were older age, higher NYHA, higher CCI, and use of the following drugs at discharge: beta blockers, loop diuretics, thiazide, and nitrates. In contrast, the independent factors associated with the decrease in 30-day readmission were longer LOS, higher BMI, and the use of angiotensin converting enzyme inhibitors (ACEs) or angiotensin II receptor blockers (ARBs), calcium channel blockers, and spironolactone. CONCLUSIONS: The results suggest that, especially during the first few weeks after discharge, careful management of HF outpatients with advanced age, high disease severity, multiple comorbidities, or taking beta blockers, loop diuretics, thiazide, and nitrates at discharge may be crucial for reducing the 30-day readmission rate.
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Insuficiência Cardíaca/tratamento farmacológico , Readmissão do Paciente , Antagonistas Adrenérgicos beta/uso terapêutico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Índice de Massa Corporal , Bases de Dados Factuais , Feminino , Humanos , Japão , Tempo de Internação , Masculino , Nitratos/uso terapêutico , Fatores de Risco , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêutico , Tiazidas/uso terapêuticoRESUMO
INTRODUCTION: Natural products (NPs) are evolutionarily designed and contain more complex and challenging structures than synthetic compounds. Since the 1980s, the pharmaceutical industry has gradually shifted to a strategy of developing targeted agents by screening libraries of synthetic compounds. However, NPs have recently received renewed focus as a rich repository for drug discovery. Irinotecan was developed as a derivative of camptothecin and was applied in standard regimens for metastatic colorectal cancer (CRC) worldwide. Additionally, polysaccharide K is approved for CRC in Japan and Taiwan in combination with cytotoxic agents. However, after the approval of irinotecan in 1996, no anti-cancer agents derived from NPs have been approved for CRC. AREAS COVERED: This review discusses NPs that are currently under investigation for the treatment of CRC. In addition, other NPs derived as purified ingredients and crude extracts are listed and also discussed. EXPERT OPINION: The use of NPs for the discovery of anti-cancer agents has not been fully investigated. New technologies that are currently applied for synthetic compounds may be utilized for anti-cancer drug discovery including NPs for CRC.
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Antineoplásicos/uso terapêutico , Produtos Biológicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Animais , Neoplasias Colorretais/patologia , Desenho de Fármacos , Descoberta de Drogas/métodos , HumanosRESUMO
OBJECTIVE: Stress is thought to be one of the triggers of relapses in patients with inflammatory bowel disease (IBD). We examined the rate of relapse in IBD patients before and after the Great East Japan Earthquake. DESIGN: A retrospective cohort study. SETTINGS: 13 hospitals in Japan. PARTICIPANTS: 546 ulcerative colitis (UC) and 357 Crohn's disease (CD) patients who received outpatient and inpatient care at 13 hospitals located in the area that were seriously damaged by the earthquake. Data on patient's clinical characteristics, disease activity and deleterious effects of the earthquake were obtained from questionnaires and hospital records. PRIMARY OUTCOME: We evaluated the relapse rate (from inactive to active) across two consecutive months before and two consecutive months after the earthquake. In this study, we defined 'active' as conditions with a partial Mayo score=2 or more (UC) or a Harvey-Bradshaw index=6 or more (CD). RESULTS: Among the UC patients, disease was active in 167 patients and inactive in 379 patients before the earthquake. After the earthquake, the activity scores increased significantly (p<0.0001). A total of 86 patients relapsed (relapse rate=15.8%). The relapse rate was about twice that of the corresponding period in the previous year. Among the CD patients, 86 patients had active disease and 271 had inactive disease before the earthquake. After the earthquake, the activity indices changed little. A total of 25 patients experienced a relapse (relapse rate=7%). The relapse rate did not differ from that of the corresponding period in the previous year. Multivariate analyses revealed that UC, changes in dietary oral intake and anxiety about family finances were associated with the relapse. CONCLUSIONS: Life-event stress induced by the Great East Japan Earthquake was associated with relapse in UC but not CD.
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Food and beverages rich in polyphenols with antioxidant activity are highlighted as a potential factor for risk reduction of lifestyle related diseases. This study was conducted to elucidate total polyphenol consumption from beverages in Japanese people. Total polyphenol (TP) contents in beverages were measured using a modified Folin-Ciocalteu method removing the interference of reduced sugars by using reverse-phase column chromatography. A beverage consumption survey was conducted in the Tokyo and Osaka areas in 2004. Randomly selected male and female subjects (10-59 years old, n = 8768) recorded the amounts and types of all nonalcoholic beverages consumed in a week. Concentration of TP in coffee, green tea, black tea, Oolong tea, barley tea, fruit juice, tomato/vegetable juice, and cocoa drinks were at 200, 115, 96, 39, 9, 34, 69, and 62 mg/100 mL, respectively. Total consumption of beverages in a Japanese population was 1.11 +/- 0.51 L/day, and TP contents from beverages was 853 +/- 512 mg/day. Coffee and green tea shared 50% and 34% of TP consumption in beverages, respectively, and contribution of each of the other beverages was less than 10%. TP contents in 20 major vegetables and 5 fruits were 0-49 mg and 2-55 mg/100 g, respectively. Antioxidant activities, Cu reducing power, and scavenging activities for DPPH and superoxide, of those samples correlated to the TP contents (p < 0.001). Beverages, especially coffee, contributed to a large share of the consumption of polyphenols, as antioxidants, in the Japanese diet.
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Antioxidantes/administração & dosagem , Café/química , Flavonoides/administração & dosagem , Fenóis/administração & dosagem , Chá/química , Adolescente , Adulto , Antioxidantes/análise , Bebidas/análise , Criança , Dieta , Feminino , Flavonoides/análise , Frutas/química , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Fenóis/análise , Polifenóis , Verduras/química , Adulto JovemRESUMO
A 73-year-old woman was admitted to our hospital for evaluation of hypochondralgia, and a thorough examination revealed an AFP producing gastric cancer with multiple liver metastases. One course of TS-1 100 mg/day for 4 weeks and discontinuation for 2 weeks was started from February, 2003. After 3 months, the level of AFP reduced remarkably from 53,700 ng/ml to the normal limit. The metastatic tumors in the liver showed regression, and after 14 months, CT scanning showed that the tumors had disappeared. Since the size of the original tumor showed no change, distal gastrectomy was performed, and curability A was achieved. We consider this rare case has significant value in terms of treatment of AFP producing gastric cancer with multiple liver metastases. We think the combination of surgery and chemotherapy such as TS-1 will lead to a better prognosis in such cases.