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Ferroelectricity in two-dimensional (2D) systems generally arises from phonons and has been widely investigated. On the contrary, electronic ferroelectricity in 2D systems has been rarely studied. Using first-principles calculations, the ferroelectric behavior of the buckled blue SiSe monolayer under strain are explored. It is found that the direction of the out-of-plane ferroelectric polarization can be reversed by applying an in-plane strain. And such polarization switching is realized without undergoing geometric inversion. Besides, the strain-triggered polarization reversal emerges in both biaxial and uniaxial strain cases, indicating it is an intrinsic feature of such a system. Further analysis shows that the polarization switching is the result of the reversal of the magnitudes of the positive and negative charge center vectors. And the variation of buckling is found to play an important role, which results in the switch. Moreover, a non-monotonic variation of band gap with strain is revealed. Our findings throws light on the investigation of novel electronic ferroelectric systems.
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Different from conventional materials, structures with a negative Poisson's ratio (NPR) contract/expand laterally under a longitudinal compressive/tensile strain, usually exhibiting peculiar features. Through first-principles calculations, we investigate the electronic and transport properties of Pd9B16 molecules. Its Poisson's ratio is found to be negative under uniaxial strain along a specific direction. By contacting with Au nanowires, atomic Au chains and atomic C chain electrodes, two kinds of transitions for transmission states could be realized by the modulation of the strain and the contacting site, i.e., metallic-semiconducting transition and spin polarized-unpolarized transition. Further analysis shows that it is the suppression and shifting of density of states, caused by the strain or contacting electrodes, that trigger the transitions. Those findings combine NPR and spintronics at the single-molecule level, which may throw light on the development of nanoelectronic devices.
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A novel HPLC method with the quantitative analysis of multi-components by single marker( QAMS) combined with the dual-wavelength method was developed for simultaneous determination of six flavonoids in Dendrobium officinale stems from different producing areas,cultivation and processing methods to clarify the main factors contributing to the different composition of flavonoids.The separation of six flavonoids was performed on a Shiseido Capcell PAK MGâ ¡ C18 column( 4. 6 mm×250 mm,5 µm) using a linear gradient elution system of acetonitrile-0. 1% formic acid aqueous solution. Schaftoside,isoschaftoside,vicenin-2,and glucosylvitexin were simultaneously analyzed using rutin as a reference standard at detection wavelength of 340 nm,and naringenin was determined at290 nm. The credibility and feasibility of QAMS method were validated and the results demonstrated that no significant differences were observed as compared with the external standard method. Finally,a total of 82 batches of D. officinale samples were analyzed and principal component analysis( PCA) and discriminant analysis were applied to distinguish and compare D. officinale samples from different producing areas,cultivation and processing methods. The results showed that the total flavonoid content of D. officinale stems cultivated in the simulated wild( attached tree cultivation or attached stone cultivation) was significantly higher than that in greenhouse bed cultivation. The content of flavonoids in simulated-wild D. officinale stems was higher in Jiangxi,Guizhou,Zhejiang,and Fujian provinces,while that in greenhouse bed cultivation was higher in Fujian and Zhejiang provinces. The content of naringenin was positively correlated with processing temperature,and that of the other five flavonoids was negatively correlated with processing temperature. PCA showed that wild-simulated D. officinale and greenhouse bed-cultivated D. officinale could be roughly divided into two clusters. The samples cultivated in the greenhouse bed were divided into four categories according to the geographical habitats. Wild-simulated D. officinale samples from Guizhou gathered together,and there was no obvious rule in samples from other producing areas. The established method simplified the determination method of flavonoids in D. officinale,and could provide the basis for effective quality control,cultivation and processing of D. officinale.
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Dendrobium , Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão , Flavonoides , Controle de QualidadeRESUMO
PURPOSE: To assess the predictive value of liver stiffness measurement (LSM) and three bleeding risk scoring systems for esophagogastric varices bleeding (EGVB) in patients with hepatitis B cirrhosis during hospitalization. METHODS: In this study, 210 patients who had hepatitis B cirrhosis were selected as the subjects. They were categorized into two groups based on whether EGVB occurred during hospitalization: a bleeding group (70 cases) and a non-bleeding group (140 cases). Logistic regression was used to analyze the factors related to the occurrence of EGVB, and the diagnostic performance was evaluated using a receiver operating characteristic (ROC) curve. RESULTS: Significant differences were observed between the two groups in systolic blood pressure, platelet count, albumin, urea nitrogen, LSM, pre-endoscopic Rockall score (PRS), Glasgow-Blatchford score (GBS), and AIMS65 score (P < 0.05). The correlation analysis showed that LSM had significant positive relationship with PRS, GBS and AIMS65 score. Logistic regression analysis revealed that LSM and GBS score were independent risk factors for EGVB occurrence during hospitalization. ROC curve analysis showed that the combined prediction model of LSM and GBS score had the best prediction performance for EGVB occurrence, with an ROC curve area of 0.811, which was significantly better than the three risk scoring systems (P < 0.05), but similar to the predicted value of LSM (P = 0.335). CONCLUSIONS: The combination of LSM and GBS score can significantly improve the predictive efficacy of EGVB occurrence in patients with hepatitis B cirrhosis during hospitalization, which has important clinical significance for patients' prognosis.
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Varizes Esofágicas e Gástricas , Hepatite B , Varizes , Humanos , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Varizes Esofágicas e Gástricas/epidemiologia , Varizes Esofágicas e Gástricas/complicações , Hemorragia Gastrointestinal/diagnóstico por imagem , Hemorragia Gastrointestinal/etiologia , Medição de Risco , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Prognóstico , Fatores de Risco , Curva ROC , Varizes/complicações , Índice de Gravidade de DoençaRESUMO
Kawasaki disease (KD) is a systemic vasculitis of unknown etiology. The laboratory findings before and after intravenous immunoglobulin (IVIG) in KD have been discussed, but the characteristics of IVIG therapy still are unclear. This study aimed to compare laboratory data from patients with KD and enterovirus (EV) infection to evaluate the differences after IVIG therapy. The study enrolled 171 KD patients and 38 EV patients treated with a single dose of IVIG from 2003 to 2010. Laboratory data including total white blood cell counts (WBC) and hemoglobin (Hb), platelet, segment, lymphocyte, eosinophil, and monocyte levels were analyzed. Compared with the KD patients, the EV patients had higher Hb, lymphocyte, and monocyte levels and lower eosinophil levels before IVIG treatment (p < 0.05). After IVIG treatment, the KD patients had lower Hb and segment levels but higher platelet, lymphocyte, and eosinophil levels than the EV patients (p < 0.05). In the KD patients, the platelet, eosinophil, and monocyte levels increased after IVIG treatment, whereas Hb, WBC, and segment levels decreased significantly (p < 0.001). In the EV patients, eosinophil levels increased after IVIG treatment, whereas WBC and Hb levels decreased significantly (p < 0.05). The study results provide evidence that eosinophilia may be related to IVIG therapy in KD and EV patients. The KD patients had higher eosinophil levels both before and after IVIG therapy than the EV patients, which may have been due to the inflammatory mechanism of KD. The KD patients had higher platelet levels than the EV patients, suggesting that platelets are involved in the inflammatory response to KD.
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Infecções por Enterovirus/tratamento farmacológico , Imunoglobulinas Intravenosas/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Biomarcadores/sangue , Distribuição de Qui-Quadrado , Infecções por Enterovirus/sangue , Feminino , Humanos , Lactente , Masculino , Síndrome de Linfonodos Mucocutâneos/sangue , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Resultado do TratamentoRESUMO
Polymorphonuclear leukocytes (PMNs) are the major leukocytes in the circulation and play an important role in host defense. Intact PMN functions include adhesion, migration, phagocytosis, and reactive oxygen species (ROS) release. It has been known for a long time that adenosine can function as a modulator of adult PMN functions. Neonatal plasma has a higher adenosine level than that of adults; however, little is known about the modulating effects of adenosine on neonatal PMNs. The aim of this study was to investigate the effects of adenosine on neonatal PMN functions. We found that neonatal PMNs had impaired adhesion, chemotaxis, and ROS production abilities, but not phagocytosis compared to adult PMNs. As with adult PMNs, adenosine could suppress the CD11b expressions of neonatal PMNs, but had no significant suppressive effect on phagocytosis. In contrast to adult PMNs, adenosine did not significantly suppress chemotaxis and ROS production of neonatal PMNs. This may be due to impaired phagocyte reactions and a poor neonatal PMN response to adenosine. Adenosine may not be a good strategy for the treatment of neonatal sepsis because of impaired phagocyte reactions and poor response.
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Adenosina/farmacologia , Neutrófilos/efeitos dos fármacos , Adulto , Humanos , Recém-NascidoRESUMO
OBJECTIVE: Kawasaki disease (KD) is an acute systematic vasculitis in children which causes coronary arterial lesions and hydrops of gallbladder. Our objective is to correlate the clinical significance and influence on disease outcome of patients with gallbladder abnormalities in Kawasaki dissease. METHODS: Children who met KD diagnosis criteria and were admitted for IVIG treatment were retrospectively enrolled for analysis. Patients with abdominal sonography were divided into 2 groups based on the absence (Group A, N = 61) or presence (Group B, N = 16) of gallbladder abnormalities (GBA), defined as hydrops or acalculous cholecystitis. Between the two groups, clinical features, demographic data (including admission days, coronary artery lesions, IVIG resistance), and laboratory data before/after IVIG treatment were collected for analysis. RESULTS: The presence of sonographic gallbladder abnormalities is correlated with higher levels of serum CRP, GPT, and neutrophils. It also points to an increased number of IVIG resistance rates in group B. There was no significant statistical difference among clinical features, age, gender, admission days, or coronary artery lesions between the two groups. CONCLUSION: Sonographic gallbladder abnormalities are associated with higher CRP, GPT, neutrophil and IVIG resistance in KD. It can be used as a predictor of IVIG resistance in patients with KD.
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Edema/complicações , Doenças da Vesícula Biliar/complicações , Vesícula Biliar/anormalidades , Vesícula Biliar/diagnóstico por imagem , Imunoglobulinas Intravenosas/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Colecistite Acalculosa/sangue , Colecistite Acalculosa/complicações , Colecistite Acalculosa/diagnóstico por imagem , Proteína C-Reativa/análise , Pré-Escolar , Resistência a Medicamentos , Edema/sangue , Edema/diagnóstico por imagem , Feminino , Doenças da Vesícula Biliar/sangue , Doenças da Vesícula Biliar/diagnóstico por imagem , Humanos , Lactente , Contagem de Leucócitos , Masculino , Síndrome de Linfonodos Mucocutâneos/sangue , Neutrófilos/citologia , Estudos Retrospectivos , Falha de Tratamento , UltrassonografiaRESUMO
The generation of spin currents is a significant issue in spintronics. A spin current can be induced by a temperature gradient in the spin-dependent Seebeck effect, which has attracted growing interest over recent years. Herein we propose spin caloritronic devices based on magnetic graphether nanoribbons and investigate the spin thermoelectric properties by first-principles calculations. Owing to the symmetrical spin-resolved transmission spectra, our devices exhibit a robust spin-dependent Seebeck effect and could generate a pure spin current. Moreover, they manifest a high spin Seebeck coefficient and a giant spin figure of merit. Our findings demonstrate that graphether-nanoribbon-based devices possess remarkable spin thermoelectric performance, and might be promising candidates for spin caloritronics.
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OBJECTIVE: Kawasaki disease (KD) is characterized by systemic vasculitis of an unknown cause. A previous study has indicated that a polymorphism of the inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) gene is involved in the susceptibility to KD. ORAI (also known as CRACM1) is one of the components of store-operated calcium channels involved in regulating immune and inflammatory reactions. This study was conducted to investigate if polymorphisms in ORAI1/CRACM1, a gene downstream from ITPKC, are associated with KD susceptibility and clinical outcomes. MATERIALS AND METHODS: A total of 1,056 subjects (341 KD patients and 715 controls) were investigated to identify five tagging single nucleotide polymorphisms (tSNPs) in ORAI1/CRACM1 (rs12313273, rs6486795, rs7135617, rs12320939, and rs712853) by using the TaqMan Allelic Discrimination assay. RESULTS: No significant associations between genotype and allele frequency of the five ORAI1/CRACM1 tSNPs were observed in the KD patients and controls. In KD patients, no significant associations between ORAI1/CRACM1 polymorphisms and coronary artery lesion (CAL) formation or intravenous immunoglobulin (IVIG) treatment response were observed. The results from haplotype analysis were insignificant. CONCLUSIONS: This study showed for the first time that ORAI1/CRACM1 polymorphisms are not associated with KD susceptibility, CAL formation, or IVIG treatment response in the Taiwanese population.
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Canais de Cálcio/genética , Síndrome de Linfonodos Mucocutâneos/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Polimorfismo de Nucleotídeo Único , Canais de Cálcio/sangue , Criança , Predisposição Genética para Doença , Genótipo , Humanos , Proteína ORAI1 , TaiwanRESUMO
Kawasaki disease (KD) is characterized by systemic vasculitis of unknown etiology. A study from Japan reported that G to A substitution of a single-nucleotide polymorphism (SNP) located in the 5'-untranslated region of caspase 3 (CASP3) (rs72689236), which was associated with nuclear factor of activated T cell-mediated T-cell activation, is responsible for susceptibility to KD. This study was conducted to investigate whether the polymorphism of CASP3 is responsible for susceptibility and coronary artery lesion (CAL) formation in KD in the Taiwanese population. A total of 1092 subjects (341 KD patients and 751 controls) were investigated to identify an SNP of rs72689236 using Invader assays (Third Wave Technologies). Our data provided a borderline significant association between the genotypes and allele frequency of rs72689236 in control subjects and KD patients (P=0.0535 under the dominant model; P=0.0575 under the allelic model). The A allele of rs72689236 in KD patients and in patients with CAL and intravenous immunoglobulin resistance was seen in a higher frequency. Importantly, a significant association was obtained between rs72689236 and KD patients with aneurysm formation (P=0.009, under the recessive model). The A allele of rs72689236 is very likely to be a risk allele in the development of aneurysm in patients with KD.
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Povo Asiático/genética , Caspase 3/genética , Síndrome de Linfonodos Mucocutâneos/genética , Polimorfismo de Nucleotídeo Único , Alelos , Estudos de Casos e Controles , Criança , Vasos Coronários/patologia , Família , Frequência do Gene , Genótipo , Humanos , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/patologia , TaiwanRESUMO
Echinocandin resistance in Candida glabrata poses a serious clinical challenge. The underlying resistance mechanism of a pan-echinocandin-resistant C. glabrata isolate (strain L74) was investigated in this study. FKS mutants carrying specific mutations found in L74 were reconstructed by the Alt-R CRISPR-Cas9 system (Fks1 WT/Fks2-E655K, strain CRISPR 31) and site-directed mutagenesis (strain fks1Δ/Fks2-E655K). Sequence analysis of strain L74 revealed a premature stop codon W508stop in FKS1 and an E655K mutation preceding the hotspot 1 region in FKS2. Introduction of the Fks2-E655K mutation in ATCC 2001 (strain CRISPR 31) conferred a modest reduction in susceptibility. However, the same FKS2 mutation in the fks1Δ background (strain fks1Δ/Fks2-E655K) resulted in high levels of resistance to echinocandins. Glucan synthase isolated from L74 was dramatically less sensitive to micafungin (MCF) relative to ATCC 2001. Both FKS1/FKS2 transcript ratios and Fks1/Fks2 protein ratios were significantly lower in L74 and fks1Δ/Fks2-E655K compared to ATCC 2001 and CRISPR 31 (P <0.05). Mice challenged with CRISPR 31 and fks1Δ/Fks2-E655K mutants failed to respond to MCF. In conclusion, the high-level of echinocandin resistance in the clinical isolate of C. glabrata L74 was concluded to result from the combination of null function of Fks1 and the point mutation E655K in Fks2.
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Antifúngicos/farmacologia , Candida glabrata/enzimologia , Candidíase/microbiologia , Farmacorresistência Fúngica , Equinocandinas/farmacologia , Proteínas Fúngicas/metabolismo , Glucosiltransferases/metabolismo , Animais , Candida glabrata/efeitos dos fármacos , Candida glabrata/genética , Feminino , Proteínas Fúngicas/genética , Glucosiltransferases/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade MicrobianaAssuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Doenças Autoimunes/tratamento farmacológico , Linfócitos B/imunologia , Fatores Imunológicos/uso terapêutico , Anticorpos Monoclonais Murinos/efeitos adversos , Doenças Autoimunes/imunologia , Ensaios Clínicos como Assunto , Humanos , Fatores Imunológicos/efeitos adversos , Rituximab , Resultado do TratamentoRESUMO
Kawasaki disease (KD) is a systemic vasculitis primarily affecting children who are younger than 5 years. The most serious complications are coronary artery aneurysms and sequelae of vasculitis with the subsequent development of coronary artery aneurysm. According to the literature, intravenous immunoglobulin (IVIG) plus high-dose aspirin (acetylsalicylic acid) were standard treatment for KD, whereas low-dose aspirin (3-5 mg/kg/day) was used for thrombocytosis in KD via antiplatelet effect. However, aspirin has been reported to have hemolytic potential in individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency. We report a child with G6PD-deficiency who has KD, and review the literature.
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Deficiência de Glucosefosfato Desidrogenase , Síndrome de Linfonodos Mucocutâneos , Humanos , Lactente , MasculinoRESUMO
Kawasaki disease (KD) is characterized by systemic vasculitis with unknown etiology. Previous studies from Japan indicated that a gene polymorphism of ITPKC (rs28493229) is responsible for susceptibility to KD. We collected DNA samples from 1,531 Taiwanese subjects (341 KD patients and 1,190 controls) for genotyping ITPKC. In this study, no significant association was noted for the ITPKC polymorphism (rs28493229) between the controls and KD patients, although the CC genotype was overrepresented. We further combined our data with previously published case/control KD studies in the Taiwanese population and performed a meta-analysis. A significant association between rs28493229 and KD was found (Odds Ratio:1.36, 95% Confidence Interval 1.12-1.66). Importantly, a significant association was obtained between rs28493229 and KD patients with aneurysm formation (Pâ=â0.001, under the recessive model). Taken together, our results indicated that C-allele of ITPKC SNP rs28493229 is associated with the susceptibility and aneurysm formation in KD patients in a Taiwanese population.