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1.
Arq Neuropsiquiatr ; 79(9): 759-765, 2021 09.
Article in English | MEDLINE | ID: mdl-34669812

ABSTRACT

BACKGROUND: Predictors of outcomes following endovascular treatment (ET) for aneurysmal subarachnoid hemorrhage (aSAH) are not well-defined. Identifying them would be beneficial in determining which patients might benefit from ET. OBJECTIVE: To identify the predictive factors for poor outcomes following ET for aSAH. METHODS: 120 patients with ruptured cerebral aneurysms underwent endovascular embolization between January 2017 and December 2018. Blood pressure variability was examined using the standard deviation of the 24-hour systolic blood pressure (24hSSD) and 24-hour diastolic blood pressure (24hDSD). Predictors were identified through univariate and multivariate regression analysis. All patients were followed up for three months. RESULTS: At follow-up, 86 patients (71.7%) had good outcomes and 34 (28.3%) had poor outcomes. Patients with poor outcomes had significantly higher 24hSSD than those with good outcomes (19.3 ± 5.5 vs 14.1 ± 4.8 mmHg; P < 0.001). The 24hDSD did not differ significantly between patients with good outcomes and those with poor outcomes (9.5 ± 2.3 vs 9.9 ± 3.5 mmHg; P = 0.464). The following were significant risk factors for poor outcomes after endovascular embolization: age ≥ 65 years (odds ratio [OR] = 23.0; 95% confidence interval [CI]: 3.0-175.9; P = 0.002); Hunt-Hess grade 3-4 (OR = 6.8; 95% CI: 1.1-33.7; P = 0.039); Fisher grade 3-4 (OR = 47.1; 95% CI: 3.8-586.5; P = 0.003); postoperative complications (OR = 6.1; 95% CI: 1.1-34.8; P = 0.042); and 24hSSD ≥ 15 mmHg (OR = 14.9; 95% CI: 4.0-55.2; P < 0.001). CONCLUSION: Elevated 24hSSD is a possibly treatable predictive factor for poor outcomes after ET for aSAH.


Subject(s)
Intracranial Aneurysm , Subarachnoid Hemorrhage , Aged , Blood Pressure , Humans , Intracranial Aneurysm/complications , Intracranial Aneurysm/therapy , Retrospective Studies , Subarachnoid Hemorrhage/therapy , Treatment Outcome
2.
Front Immunol ; 12: 695491, 2021.
Article in English | MEDLINE | ID: mdl-34489943

ABSTRACT

Patients with liver disease are susceptible to infection with Vibrio vulnificus (V. vulnificus), but the specific reasons remain elusive. Through RNA-seq, we found that when mice with alcoholic liver disease (ALD) were infected with V. vulnificus by gavage, compared with the Pair group, the small intestinal genes affecting intestinal permeability were upregulated; and the number of differentially expressed genes related to immune functions (e.g., such as cell chemotaxis, leukocyte differentiation, and neutrophil degranulation) decreased in the liver, spleen, and blood. Further analysis showed that the number of white blood cells decreased in the Pair group, whereas those in the ALD mice did not change significantly. Interestingly, the blood bacterial load in the ALD mice was about 100 times higher than that of the Pair group. After the ALD mice were infected with V. vulnificus, the concentrations of T cell proliferation-promoting cytokines (IL-2, IL-23) decreased. Therefore, unlike the Pair group, ALD mice had weaker immune responses, lower T cell proliferation-promoting cytokines, and higher bacterial loads post-infection, possibly increasing their susceptibility to V. vulnificus infection. These new findings we presented here may help to advance the current understanding of the reasons why patients with liver disease are susceptible to V. vulnificus infection and provides potential targets for further investigation in the context of treatment options for V. vulnificus sepsis in liver disease patient.


Subject(s)
Cytokines/metabolism , Liver Diseases, Alcoholic/immunology , Transcriptome , Vibrio Infections/immunology , Vibrio vulnificus/pathogenicity , Animals , Bacterial Load , Cell Proliferation , Cytokines/genetics , Disease Models, Animal , Female , Gene Expression Profiling , Host-Pathogen Interactions , Liver Diseases, Alcoholic/genetics , Liver Diseases, Alcoholic/metabolism , Lymphocyte Activation , Mice, Inbred C57BL , RNA-Seq , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , T-Lymphocytes/microbiology , Vibrio Infections/genetics , Vibrio Infections/metabolism , Vibrio vulnificus/growth & development , Vibrio vulnificus/immunology
3.
Arq. neuropsiquiatr ; 79(9): 759-765, Sept. 2021. tab, graf
Article in English | LILACS | ID: biblio-1345343

ABSTRACT

ABSTRACT Background: Predictors of outcomes following endovascular treatment (ET) for aneurysmal subarachnoid hemorrhage (aSAH) are not well-defined. Identifying them would be beneficial in determining which patients might benefit from ET. Objective: To identify the predictive factors for poor outcomes following ET for aSAH. Methods: 120 patients with ruptured cerebral aneurysms underwent endovascular embolization between January 2017 and December 2018. Blood pressure variability was examined using the standard deviation of the 24-hour systolic blood pressure (24hSSD) and 24-hour diastolic blood pressure (24hDSD). Predictors were identified through univariate and multivariate regression analysis. All patients were followed up for three months. Results: At follow-up, 86 patients (71.7%) had good outcomes and 34 (28.3%) had poor outcomes. Patients with poor outcomes had significantly higher 24hSSD than those with good outcomes (19.3 ± 5.5 vs 14.1 ± 4.8 mmHg; P < 0.001). The 24hDSD did not differ significantly between patients with good outcomes and those with poor outcomes (9.5 ± 2.3 vs 9.9 ± 3.5 mmHg; P = 0.464). The following were significant risk factors for poor outcomes after endovascular embolization: age ≥ 65 years (odds ratio [OR] = 23.0; 95% confidence interval [CI]: 3.0-175.9; P = 0.002); Hunt-Hess grade 3-4 (OR = 6.8; 95% CI: 1.1-33.7; P = 0.039); Fisher grade 3-4 (OR = 47.1; 95% CI: 3.8-586.5; P = 0.003); postoperative complications (OR = 6.1; 95% CI: 1.1-34.8; P = 0.042); and 24hSSD ≥ 15 mmHg (OR = 14.9; 95% CI: 4.0-55.2; P < 0.001). Conclusion: Elevated 24hSSD is a possibly treatable predictive factor for poor outcomes after ET for aSAH.


RESUMO Antecedentes: Fatores preditores de resultados após tratamento endovascular (TE) para hemorragia subaracnóide aneurismática (HSA) não estão bem definidos. Identificá-los seria útil para determinar quais pacientes podem se beneficiar de TE. Objetivo: Identificar os fatores preditivos de resultados ruins após TE para HSA. Métodos: 120 pacientes com aneurismas cerebrais rompidos foram submetidos à embolização endovascular entre janeiro de 2017 e dezembro de 2018. A variabilidade da pressão arterial foi examinada usando-se o desvio padrão da PA sistólica de 24 horas (DPPAS- 24h) e da PA diastólica de 24 horas (DPPAD-24h). Os fatores preditores foram identificados por meio de análises de regressão univariada e multivariada. Todos os pacientes foram acompanhados por três meses. Resultados: No acompanhamento, 86 pacientes (71,7%) tiveram bons resultados e 34 (28,3%) tiveram resultados ruins. Pacientes com resultados ruins apresentaram DPPAS-24h significativamente maior do que aqueles com bons resultados (19,3 ± 5,5 vs 14,1 ± 4,8 mmHg; P <0,001). O DPPAD-24h não diferiu significativamente entre os pacientes com bons resultados e aqueles com resultados ruins (9,5 ± 2,3 vs 9,9 ± 3,5 mmHg; P = 0,464). Os fatores de risco significativos para resultados ruins após embolização endovascular foram os seguintes: idade ≥ 65 anos (razão de probabilidade [OR] = 23,0; intervalo de confiança de 95% [IC]: 3,0-175,9; P = 0,002); escala de Hunt-Hess 3-4 (OR = 6,8; IC 95%: 1,1-33,7; P = 0,039); escala de Fisher 3-4 (OR = 47,1; IC 95%: 3,8-586,5; P = 0,003); complicações pós-operatórias (OR = 6,1; IC 95%: 1,1-34,8; P = 0,042); e DPPAS 24h ≥ 15 mmHg (OR = 14,9; IC 95%: 4,0-55,2; P <0,001). Conclusão: O DPPAS 24h elevado é um fator preditivo possivelmente tratável para resultados ruins após TE para HSA.


Subject(s)
Humans , Aged , Subarachnoid Hemorrhage/therapy , Intracranial Aneurysm/complications , Intracranial Aneurysm/therapy , Blood Pressure , Retrospective Studies , Treatment Outcome
4.
Medicine (Baltimore) ; 100(19): e25874, 2021 May 14.
Article in English | MEDLINE | ID: mdl-34106640

ABSTRACT

BACKGROUND: Autism spectrum disorder is a neurodevelopmental disorder with increasing incidence. At present, the global incidence of the disease is on the rise, and the cause is unknown. There is no specific treatment for this disease at present, mainly education and training. Traditional Chinese medicine treatment has a certain effect on the improvement of the symptoms of the disease. The treatment methods are mainly oral Chinese medicine and acupuncture, but children are often not easy to cooperate. As a safe and effective green therapy, massage is easy to be accepted by children. METHODS: We will search the following electronic databases for randomized controlled trials to evaluate the effectiveness and safety of massage therapy in treating autism spectrum disorders: Wanfang and PubMed Database, China National Knowledge Infrastructure Database, Cochrane Central Register of Controlled Trials, Cumulative Index of Nursing and Allied Health Literature, and Excerpta Medica database. Each database will be searched from inception to March 2021. The entire process will include study selection, data extraction, risk of bias assessment, and meta-analyses. RESULTS: This proposed study will evaluate the effectiveness and safety of massage therapy for patients with autism spectrum disorders. The outcomes will include changes in autism spectrum disorder relief and adverse effect. CONCLUSION: This proposed systematic review will evaluate the existing evidence on the effectiveness and safety of massage therapy for patients with autism spectrum disorders. DISSEMINATION AND ETHICS: The results of this review will be disseminated through peer-reviewed publication. Because all of the data used in this systematic review and meta-analysis have been published, this review does not require ethical approval. Furthermore, all data will be analyzed anonymously during the review process.


Subject(s)
Autism Spectrum Disorder/therapy , Massage/methods , Humans , Massage/adverse effects , Randomized Controlled Trials as Topic , Research Design , Meta-Analysis as Topic
5.
ACS Omega ; 4(6): 10516-10523, 2019 Jun 30.
Article in English | MEDLINE | ID: mdl-31460149

ABSTRACT

Proper design and development of near-infrared (NIR) fluorescent sensors is very important for applications in vivo. In this work, we theoretically designed a ratiometric and NIR fluorescent sensor based on the 10-hydroxybenzo[h]quinoline (HBQ) backbone via systematically investigating the substituent effects of electron-donating groups (-NH2, -CH3, -C(CH3)3) and electron-withdrawing groups (-NO2, -CN, -F, -Cl, -CF3) at the proton donor site on the proton transfer process in HBQ in both the S0 and the S1 states. According to the calculated potential energy profiles along the proton transfer as well as the photophysical properties among all the derivatives, we successfully screened out that 7NH2-HBQ is a promising fluorescent sensor exhibiting the near IR emission spectra accompanied by the large Stokes shift. The potential use of 7NH2-HBQ for F- detection among anions (F-, Cl-, and Br-) was further studied, and the results showed that 7NH2-HBQ is very sensitive and selective toward F- based on the intermolecular hydrogen bonding interaction between F- and OH bond, forming a new complex FACS0 . The ratiometric change in the fluorescence intensity could be induced by the H-F bond transfer from the O atom to the N atom in the S1 state.

6.
J Mol Model ; 24(8): 205, 2018 Jul 14.
Article in English | MEDLINE | ID: mdl-30008049

ABSTRACT

Aluminum nitride nanotubes (AlNNTs) doped by the excess electron, e@AlNNT and M@N-AlNNT (M = Li, Na, K), have been designed and their geometrical, electronic, and nonlinear optical (NLO) properties have been explored theoretically. The results showed that the excess electron narrows the energy gap between HOMO and LUMO values (EH-L) of the doped systems in the range of 3.42-5.37 eV, which is due to a new energy level HOMO formed for the doped excess electron, with higher energy than the original HOMO of AlNNT. Importantly, the doped excess electron considerably increases the first hyperpolarizability (ß0) from 130 a.u. of the undoped AlNNT to 646 a.u. for e@AlNNT, 2606 a.u. for Li@N-AlNNT, while 1.14 × 105 a.u. for Na@N-AlNNT, and 1.37 × 106 a.u. for K@N-AlNNT. The enormous ß0 values for Na@N-AlNNT and K@N-AlNNT are attributed to the low transition energy. These results demonstrate that AlNNTs are a promising material in high-performance NLO nanomaterials for electronic devices.

7.
ACS Appl Mater Interfaces ; 7(24): 13707-13, 2015 Jun 24.
Article in English | MEDLINE | ID: mdl-26040628

ABSTRACT

Ti2C is one of the thinnest layers in MXene family with high potential for applications. In the present study, the adsorption of NH3, H2, CH4, CO, CO2, N2, NO2, and O2 on monolayer Ti2CO2 was investigated by using first-principles simulations to exploit its potential applications as gas sensor or capturer. Among all the gas molecules, only NH3 could be chemisorbed on Ti2CO2 with apparent charge transfer of 0.174 e. We further calculated the current-voltage (I-V) relation using the nonequilibrium Green's function (NEGF) method. The transport feature exhibits distinct responses with a dramatic change of I-V relation before and after NH3 adsorption on Ti2CO2. Thus, we predict that Ti2CO2 could be a promising candidate for the NH3 sensor with high selectivity and sensitivity. On the other hand, the adsorption of NH3 on Ti2CO2 could be further strengthened with the increase of applied strain on Ti2CO2, while the adsorption of other gases on Ti2CO2 is still weak under the same strain, indicating that the capture of NH3 on Ti2CO2 under the strain is highly preferred over other gas molecules. Moreover, the adsorbed NH3 on Ti2CO2 could be escapable by releasing the applied strain, which indicates the capture process is reversible. Our study widens the application of monolayer Ti2CO2 not only as the battery material, but also as the potential gas sensor or capturer of NH3 with high sensitivity and selectivity.

8.
Luminescence ; 30(4): 382-7, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25044504

ABSTRACT

Procaterol hydrochloride (Prh) can inhibit KClO3 oxidation of fluorescein isothiocyanate (FITC) to form a non-phosphorescent compound, which causes room temperature phosphorescence (RTP) of FITC in the system to enhance sharply the linear relationship between ∆Ip and the Prh content. Thus, a rapid response and highly sensitive phosphorescence sensor for the determination of Prh has been developed based on the inhibiting effect of Prh on KClO3 oxidation of FITC. This simple, high sensitivity (detection limit (LD) calculated by 3Sb /k was 0.019 fg/spot, sample volume 0.40 µl, corresponding concentration 4.8 × 10(-14) g ml(-1) ) and selective sensor with a wide linear range (0.080-11.20 g/spot) has been applied to detect Prh in blood samples, and the results were consistent with those obtained by high-performance liquid chromatography (HPLC). Simultaneously, the mechanism of the phosphorescence sensor for the detection of Prh was also investigated using infrared spectroscopy.


Subject(s)
Fluorescein-5-isothiocyanate/chemistry , Luminescent Measurements/methods , Procaterol/analysis , Procaterol/pharmacology , Animals , Chlorates/chemistry , Chromatography, High Pressure Liquid , Fluorescent Dyes/chemistry , Humans , Limit of Detection , Oxidation-Reduction , Procaterol/blood , Procaterol/urine , Sensitivity and Specificity , Spectrophotometry, Infrared , Sus scrofa
9.
J Phys Chem A ; 119(11): 2217-24, 2015 Mar 19.
Article in English | MEDLINE | ID: mdl-25029257

ABSTRACT

A tetrel-hydride interaction was predicted and characterized in the complexes of XH3F···HM (X = C, Si, Ge, Sn; M = Li, Na, BeH, MgH) at the MP2/aug-cc-pVTZ level, where XH3F and HM are treated as the Lewis acid and base, respectively. This new interaction was analyzed in terms of geometrical parameters, interaction energies, and spectroscopic characteristics of the complexes. The strength of the interaction is essentially related to the nature of X and M groups, with both the larger atomic number of X and the increased reactivity of M giving rise to a stronger tetrel-hydride interaction. The tetrel-hydride interaction exhibits similar substituent effects to that of dihydrogen bonds, where the electron-donating CH3 and Li groups in the metal hydride strengthen the binding interactions. NBO analyses demonstrate that both BD(H-M) → BD*(X-F) and BD(H-M) → BD*(X-H) orbital interactions play the stabilizing role in the formation of the complex XH3F···HM (X = C, Si, Ge, and Sn; M = Li, Na, BeH, and MgH). The major contribution to the total interaction energy is electrostatic energy for all of the complexes, even though the dispersion/polarization parts are nonnegligible for the weak/strong tetrel-hydride interaction, respectively.

10.
J Fluoresc ; 24(6): 1775-83, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25294182

ABSTRACT

Fluorescein (HFin) could emit strong and stable room temperature phosphorescence (RTP) signal on polyamide membrane (PAM) using Pb(2+) as the ion perturber. Carbaryl could activate effect on NaIO4 oxidating HFin, which caused the RTP signal of the system to quench sharply. The phosphorescence intensity (ΔI p) of activating system higher 3.3 times (119.4/36.0) than that of non-activating system, and is directly proportional to the content of carbaryl. Thus, an activating solid substrate room temperature phosphorimetry (SSRTP) for carbaryl detection has been established. This sensitive (the limit of quantification (LOQ) was 2.0 × 10(-13) g mL(-1)), selective, simple and rapid method has been applied to determine trace carbaryl in water samples with the results consisting with those obtained by fluorimetry, showing its high accuracy. The apparent activation energy (E) and rate constant (k) of this activating reaction were 20.77 kJ mol(-1) and 1.85 × 10(-4) s(-1), respectively. Meanwhile, the mechanism of activating SSRTP for carbaryl detection was also discussed using infrared spectra (IR).

11.
J Fluoresc ; 24(5): 1495-501, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25155629

ABSTRACT

A highly sensitive fluorescent probe for clenbuterol hydrochloride (CLB) detection has been first designed based on its catalytic effect on NaIO4 oxidating eosine Y (R). And this environment-friendly, simple, rapid, selective and sensitive fluorescent probe has been utilized to detect CLB in the practical samples with the results consisting with those obtained by GC/MS. The structures of R and CLB were characterized by infrared spectra. The mechanism of the proposed assay for the detection of CLB was also discussed.


Subject(s)
Clenbuterol/analysis , Eosine Yellowish-(YS)/chemistry , Fluorescent Dyes/chemistry , Periodic Acid/chemistry , Catalysis , Luminescent Measurements , Molecular Structure , Oxidation-Reduction
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(9): 2492-5, 2013 Sep.
Article in Chinese | MEDLINE | ID: mdl-24369659

ABSTRACT

Using pure human serum albumin (HSA) as the model protein, the effects of protein on the extraction of antipsychotic drugs (APDs: diazepam, chlorpromazine hydrochloride, and perphenazine) in human serum sample were studied. The present paper investigated the interaction between APDs and HSA by fluorescence spectrometry in detail The influences of different ethanol concentration solution on protein denaturation were studied by Rayleigh scattering. The results showed that APDs strongly bound with HSA. In the phi (ethanol) 80% extracting solution, a slow but full protein denaturation takes place, which causes the unfolding of protein and the dissociation of drugs. Then K2 HPO4 was added into the extracting solution to form aqueous two-phase system, and meanwhile the drug residues were extracted into upper phase with high extraction efficiencies. After filtration, the upper phase was ready for analysis of drug residues by HPLC system. The detection limits were in the range of 18.8-38.4 ng x mL(-1), and the spiked recovery was 94.2%-98.7% for determination of antipsychotic drugs in human serum. The method is efficient, solvent-saving, environment-friendly, and accurate.


Subject(s)
Antipsychotic Agents/blood , Drug Residues/analysis , Serum Albumin , Humans , Protein Denaturation , Spectrometry, Fluorescence
13.
J Phys Chem A ; 117(30): 6678-86, 2013 Aug 01.
Article in English | MEDLINE | ID: mdl-23819837

ABSTRACT

Interesting effects of the cage unit size and number of cage units as well as bridge unit on the static first hyperpolarizabilities (ß0) for novel multicage electrides are revealed. (1) The small cage unit C8 systems have larger ß0 for cage unit size effect. (2) The ß0 increases with increasing cage unit number. (3) The effect of the bridge between cage units on ß0 is O > NH > CH2. Specially, a novel relationship between the excess electron cloud and ß0 is revealed. Assembling the three effects, the constructed multicage electride structure with three small C8 cage units connected by the O-bridge (K···3C8(O)) is a electride salt K(+)[e@3C8(O)](-) and has the considerable ß0 value of 7.1 × 10(5) au, which is about 55 times larger than the 13 000 au of the single-cage electride molecule Na3O(+)(e@C20F20)(-). The novel multicage strategy is effective to enhance nonlinear optical (NLO) response.

14.
J Fluoresc ; 22(1): 419-29, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21947608

ABSTRACT

The labelling reagent CdSe@CdS-QDs-Cys (QDs-Cys) with the grain diameter of 4.5 nm was synthesized by modifying CdSe@CdS quantum dots (QDs) with cysteine (Cys). At the same time, QDs-Cys-Ab(IgE), a phosphorescent quantum dot probe, was developed based on the labelling reaction between -COOH of QDs-Cys and -NH(2) of goat anti human IgE antibody (Ab(IgE)). This probe with excellent biocompatibility and high specificity could not only emit strong and stable room temperature phosphorescence (RTP), but also could carry out specific immunoassay (IA) with immunoglobulin E (IgE), causing the RTP of the system to sharply enhance. Thus, a new solid substrate room temperature phosphorescence immunoassay (SSRTPIA) for the determination of IgE was established. The limit of quantification (LOQ) of the method was 0.12 fg spot(-1), corresponding concentration was 3.0 × 10(-13) g mL(-1) and sampling quantity was 0.40 µL spot(-1). This highly selective, sensitive and accurate SSRTPIA has been applied to determine IgE in biological samples and diagnose diseases, and the results agreed well with those obtained by enzyme-link immunoassay (ELISA). Meanwhile, the mechanisms of QDs-Cys labelling Ab(IgE) and the determination of IgE by SSRTPIA were also discussed.


Subject(s)
Cadmium Compounds/chemistry , Cysteine/chemistry , Immunoassay/methods , Immunoglobulin E/analysis , Quantum Dots , Selenium Compounds/chemistry , Sulfides/chemistry , Temperature , Calibration , Fluorescent Dyes/chemistry , Humans , Humidity , Immunoglobulin E/blood , Membranes, Artificial , Oxygen/chemistry , Spectrometry, Fluorescence , Time Factors
15.
J Phys Chem A ; 115(8): 1418-22, 2011 Mar 03.
Article in English | MEDLINE | ID: mdl-21302909

ABSTRACT

It is well-known that single H3N-HCl and H2O-HCl acid-base pairs do not react to form the ion pairs, H4N(+)Cl(-) and H3O(+)Cl(-), in isolation. On the basis of ab initio method, we propose a physical method of external electric field (Eext) to drive the proton transfer from acid (HCl) to base (NH3/H2O). Our results show that when Eext along the proton-transfer direction achieves or exceeds the critical electric field (Ec), the proton transfer occurs, such as, the Ec values of proton transfer for H3N-HCl and H2O-HCl are 54 × 10(-4) and 210 × 10(-4) au, respectively. And the degree of the proton transfer can be controlled by modulating the strength of Eext. Furthermore, we estimate the inductive strength of an excess electron (Ee) equivalent to the Eext = 125 × 10(-4) au, which is greater than the Ec (54 × 10(-4) au) of NH3-HCl but less than the Ec (210 × 10(-4) au) of H2O-HCl. This explains well the anion photoelectron spectroscopy [Eustis et al. Science 2008, 319, 936] that an excess electron can trigger the proton transfer for H3N-HCl but not for H2O-HCl. On the basis of the above estimation, we also predict that two excess electrons can induce H2O-HCl to undergo the proton transfer and form the ion pair H3O(+)Cl(-).


Subject(s)
Ammonia/chemistry , Electromagnetic Fields , Hydrochloric Acid/chemistry , Models, Chemical , Protons , Water/chemistry , Electrons
16.
Chemistry ; 17(8): 2414-9, 2011 Feb 18.
Article in English | MEDLINE | ID: mdl-21319235

ABSTRACT

Graphene nanoribbon (GNR) has been used, for the first time, as an excellent conjugated bridge in a donor-conjugated bridge-acceptor (D-B-A) framework to design high-performance second-order nonlinear optical materials. Owing to the unique diradical planar conjugated bridge of GNR, D(NH(2))-GNR-A(NO(2)) exhibits exceptionally large static first hyperpolarizability (ß(0)) up to 2.5×10(6) a.u. (22000×10(-30) esu) for H(2)N-(7,3)ZGNR-NO(2) (ZGNR=zigzag-edged GNR), which is about 15 times larger than the recorded value of ß(0) (1470×10(-30) esu) for the D-A polyene reported by Blanchard-Desce et al. [Chem. Eur. J. 1997, 3, 1091]. Interestingly, we have found that the size effect of GNR plays a key role in increasing ß(0) for the H(2)N-GNR-NO(2) system, in which the width effect of GNR perpendicular to the D-A direction is superior to the length effect along the D-A direction.

17.
Phys Chem Chem Phys ; 13(6): 2266-71, 2011 Feb 14.
Article in English | MEDLINE | ID: mdl-21125096

ABSTRACT

The properties and applications of halogen bonds are dependent greatly on their strength. In this paper, we suggested some measures for enhancing the strength of the halogen bond relative to the hydrogen bond in the H(2)CS-HOX (X = F, Cl, and Br) system by means of quantum chemical calculations. It has been shown that with comparison to H(2)CO, the S electron donor in H(2)CS results in a smaller difference in strength for the Cl halogen bond and the corresponding hydrogen bond, and the Br halogen bond is even stronger than the hydrogen bond. The Li atom in LiHCS and methyl group in MeHCS cause an increase in the strength of halogen bonding and hydrogen bonding, but the former makes the halogen bond stronger and the latter makes the hydrogen bond stronger. In solvents, the halogen bond in the Br system is strong enough to compete with the hydrogen bond. The interaction nature and properties in these complexes have been analyzed with the natural bond orbital theory.


Subject(s)
Halogens/chemistry , Lithium/chemistry , Quantum Theory , Solvents/chemistry , Hydrogen Bonding , Models, Chemical , Models, Molecular , Thermodynamics
18.
J Fluoresc ; 21(1): 195-202, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20665096

ABSTRACT

Using Pb(2+) as ion perturber, phenosafranine (PF) and fluorescein isothiocyanate (FITC) could emit strong and stable room temperature phosphorescence (RTP) signal on the filter paper, respectively. When they were mixed, the phenomenon that the RTP signal of PF and FITC enhanced significantly was found. And 1.12 ag DNA spot(-1) (sample volume was 0.40 µL, corresponding concentration was 2.8 × 10(-15) g mL(-1)) could cause the RTP signal of both PF and FITC to enhance sharply. The content of DNA was proportional to the ΔI(p) of PF and FITC in the system at 634 and 659 nm. Thus, a new solid substrate room temperature phosphorimetry (SSRTP) for the determination of trace DNA was established by using FITC-PF as double-luminescent phosphorescence probe. The detection limit (LD) of this method calculated by 3S(b)/k was 14 zg DNA spot(-1) for PF and 18 zg DNA spot(-1) for FITC, respectively, showing high sensitivity. It has been applied to the determination of trace DNA in practical samples and the analysis results were in accordance with those of fluorescence probe. The reaction mechanism of SSRTP for the determination of trace DNA was also discussed.


Subject(s)
DNA/analysis , Fluorescein-5-isothiocyanate/chemistry , Phenazines/chemistry , Spectrum Analysis/methods , Limit of Detection , Luminescence , Molecular Probes
19.
Phys Chem Chem Phys ; 12(35): 10562-8, 2010 Sep 21.
Article in English | MEDLINE | ID: mdl-20614052

ABSTRACT

Differing from the reported strategy of push or pull electron effects of the complexant, a new strategy of the combination effects of both push and pull electrons of the complexant to enhance the first hyperpolarizability is performed with two Li atom doped complexants with a pair of difluorophenyl subunit rings. Large variance of the static first hyperpolarizabilities (beta(0)) are exhibited at the MP2/6-311++G(d,p) level. The order of the beta(0) values is 2.9 x10(2) (complexant UD) << 5.9 x 10(3) (LL) < 1.9 x 10(4) (H-L) < 2.3 x 10(4) (H(F)-L) < 3.2 x 10(4) (L-L) < 7.8 x 10(5) a.u. (H(F)-L(F)). It is found that H(F)-L(F) with the edge-type push-pull electronic effect of the complexant has the largest beta(0). The edge-type push-pull electronic effect brings a 2700 times increase in the beta(0) from the UD to H(F)-L(F) structure. It shows that the push-pull electronic effect is a highly effective strategy to enhance the beta(0) value. The beta(0) (7.8 x 10(5) a.u.) of the H(F)-L(F) is considerable, due to the small DeltaE and the very large Delta mu (18.085 a.u.), which comes from the corresponding long-range charge transfer transition. It is interesting that a pair of subunit rings of the complexant may have different electronic effects. In H-L and H(F)-L(F), the left ring with a longer distance between Li and the subunit ring exhibits a push electronic effect, while the right ring with the shorter distance exhibits a pull electronic effect. This work may contribute to the development of potential high-performance nonlinear optical materials.

20.
Anal Chim Acta ; 663(2): 184-9, 2010 Mar 24.
Article in English | MEDLINE | ID: mdl-20206009

ABSTRACT

8-Quinolineboronic acid phosphorescent molecular switch (8-QBA-PMS) in the "off" state emitted weak room temperature phosphorescence (RTP) of 8-QBA on the acetylcellulose membrane (ACM) with the perturbation of Pb(2+). When 8-QBA-PMS was used to label concanavalin agglutinin (Con A) to form 8-QBA-PMS-Con A based on the reaction between -OH of 8-QBA-PMS and -COOH of Con A, 8-QBA-PMS turned "on" automatically due to its structure change, and RTP of the system increased 2.7 times. Besides, -NH(2) of 8-QBA-PMS-Con A could carry out affinity adsorption (AA) reaction with the -COOH of alpha-fetoprotein variant (AFP-V) to form the product Con A-AFP-V-Con A-8-QBA-PMS containing -NH-CO- bond, causing the RTP of the system to further increase. Moreover, the amount of AFP-V was linear to the DeltaI(p) of the system in the range of 0.012-2.40 (fg spot(-1)). Thus, a new affinity sensitive adsorption solid substrate room temperature phosphorimetry using 8-QBA-PMS as labelling reagent (8-QBA-PMS-AASSRTP) for the determination of AFP-V was proposed with the detection limit (LD) of 9 x 10(-15) g mL(-1). It had been used to determine AFP-V in human serum with the results agreeing with enzyme-link immunoassay (ELISA), showing promise for the prediction of PHC due to the intimate association between AFP-V and primary hepatocellular carcinoma (PHC). The mechanism of the promethod was also discussed.


Subject(s)
Boronic Acids/chemistry , Carcinoma, Hepatocellular/chemistry , Liver Neoplasms/chemistry , Luminescent Agents/chemistry , Quinolines/chemistry , alpha-Fetoproteins/analysis , Carcinoma, Hepatocellular/blood , Humans , Liver Neoplasms/blood , Luminescent Measurements , Protein Isoforms/blood , Sensitivity and Specificity , Temperature
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