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1.
J Am Chem Soc ; 146(2): 1667-1680, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38175122

RESUMEN

Ultraviolet organic light-emitting diodes (UV OLEDs) have attracted increasing attention because of their promising applications in healthcare, industry, and agriculture; however, their development has been hindered by the shortage of robust UV emitters. Herein, we embedded double boron-oxygen units into nonlinear polycyclic aromatic hydrocarbons (BO-PAHs) to regulate their molecular configurations and excited-state properties, enabling novel bent BO-biphenyl (BO-bPh) and helical BO-naphthyl (BO-Nap) emitters with hybridized local and charge-transfer (HLCT) characteristics. They could be facilely synthesized in gram-scale amounts via a highly efficient two-step route. BO-bPh and BO-Nap showed strong UV and violet-blue photoluminescence in toluene with full width at half-maximum values of 25 and 37 nm, along with quantum efficiencies of 98 and 99%, respectively. A BO-bPh-based OLED showed high color purity UV electroluminescence peaking at 394 nm with Commission Internationale de l'Eclairage (CIE) coordinates of (0.166, 0.021). Moreover, the device demonstrated a record-high maximum external quantum efficiency (EQE) of 11.3%, achieved by successful hot exciton utilization. This work demonstrates the promising potential of double BO-PAHs as robust emitters for future UV OLEDs.

2.
Int J Behav Nutr Phys Act ; 21(1): 17, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355565

RESUMEN

BACKGROUND: How physical activity (PA) and different sleep traits and overall sleep pattern interact in the development of Parkinson's disease (PD) remain unknown. OBJECTIVE: To prospectively investigate the joint associations of PA and sleep pattern with risk of PD. METHODS: Included were 339,666 PD-free participants from the UK Biobank. Baseline PA levels were grouped into low (< 600 MET-mins/week), medium (600 to < 3000 MET-mins/week) and high (≥ 3000 MET-mins/week) according to the instructions of the UK Biobank. Healthy sleep traits (chronotype, sleep duration, insomnia, snoring, and daytime sleepiness) were scored from 0 to 5 and were categorized into "ideal sleep pattern" (≥ 3 sleep scores) and "poor sleep pattern" (0-2 sleep scores). Hazard ratios (HRs) and 95% confidence intervals (CIs) of PD were estimated by Cox proportional hazards models. RESULTS: During a median of 11.8 years of follow-up, 1,966 PD events were identified. The PD risk was lower in participants with high PA (HR = 0.73; 95% CI: 0.64, 0.84), compared to those with low PA; and participants with ideal sleep pattern also had a lower risk of PD (HR = 0.78; 95% CI: 0.69, 0.87), compared to those with poor sleep pattern. When jointly investigating the combined effect, participants with both high PA and ideal sleep pattern had the lowest risk of incident PD (HR = 0.55; 95% CI: 0.44, 0.69), compared to those with low PA and poor sleep pattern; notably, participants with high PA but poor sleep pattern also gained benefit on PD risk reduction (HR = 0.74; 95% CI: 0.55, 0.99). CONCLUSIONS: Both high PA and ideal sleep pattern were independently associated with lower risk of developing PD, and those with both high PA level and ideal sleep pattern had the lowest risk. Our results suggest that improving PA levels and sleep quality may be promising intervention targets for the prevention of PD.


Asunto(s)
Enfermedad de Parkinson , Humanos , Estudios de Cohortes , Enfermedad de Parkinson/epidemiología , Sueño , Ejercicio Físico , Conducta de Reducción del Riesgo , Factores de Riesgo
3.
Inorg Chem ; 63(14): 6435-6444, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38537132

RESUMEN

Two novel six-membered perimidocarbene (PIC)-based tetradentate Pt(II) complexes were designed and successfully synthesized. Systematical experimental and theoretical studies suggest that the PIC moiety greatly affects the frontier orbitals, as well as the photophysical and excited-state properties of the Pt(II) complexes. PtYK2 has a broad emission spectrum peaking at 576 nm with a shoulder band at 620 nm, along with a full width at half-maximum (FWHM) value of 100.0 nm at 77 K in 2-MeTHF; however, the emission spectrum is slightly red-shifted with a dominant peak at 610 nm and a FWHM value of 125.0 nm at room temperature in a poly(methyl methacrylate) (PMMA) film. Time-dependent-density functional theory and natural transition orbital analyses reveal that PtYK2 has a 3LC (3πPIC* → πPIC)-dominated character with an unexpectedly negligible contribution of 3MLCT transition (0.68%) in the T1 state, which results in a broad emission spectrum and a relatively low quantum efficiency of 7.4% in the PMMA film.

4.
Inorg Chem ; 63(19): 8822-8831, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38696545

RESUMEN

This study presents the rare examples of S-heteroaryl tetradentate Pt(S^C^N^O) luminescent complexes (PtSZ and PtSZtBu) containing a Pt-S bond. The presence of the Pt-S bond allows the novel Pt(S^C^N^O) complexes to exhibit temperature-dependent phosphorescent emission behavior. The PtSZtBu exhibits dual-emission phenomena and biexponential transient decay spectra above 250 K, indicating the presence of two minimal excited states in the potential energy surface (PES) of the T1 state. Through complementary experimental and computational studies, we have identified changes in orbital composition between Pt(dxy)-S(px) and Pt(dyz)-S(pz) in excited states with increasing temperature. This results in two energy minima, enabling the excited states to decay selectively and radiatively at different temperatures. Consequently, this leads to remarkable steady-state and transient emission spectra changes. Our work not only provides valuable insights for the development of novel Pt-S bond-based tetradentate Pt(II) complexes but also enhances our understanding of the distinctive properties governed by the Pt-S bond.

5.
Inorg Chem ; 62(32): 13156-13164, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37531143

RESUMEN

A series of novel tetradentate 6/6/6 Pt(II) complexes containing an 8-phenylquinoline-benzo[d]imidazole-carbazole ligand was designed; the Pt(II) complexes could be synthesized by metalizing the corresponding ligand with K2PtCl4 in high isolated yields of 60-90%. Experimental and theoretical studies suggested that the ligand modification of the quinoline moieties of the Pt(II) complexes could tune their electrochemical, photophysical, and excited-state properties. Notably, all the Pt(II) complexes exhibited highly electrochemical stabilities with reversible redox processes except the quasi-reversible reduction of PtYL3. The large π-conjugation of the ligand together with increased metal-to-ligand charge-transfer (3MLCT) characters in T1 states enabled the Pt(II) complexes to show broad Gaussian-type NIR emission spectra with high photoluminescence quantum efficiencies of 1.2-1.5% and short τ of 0.8-1.5 µs in dichloromethane at room temperature. This work should provide a valuable reference for the design and development of monomer NIR emitters.

6.
Philos Trans A Math Phys Eng Sci ; 381(2260): 20220388, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37742709

RESUMEN

In this paper, a time variant uncertainty propagation (TUP) method for dynamic structural system with high-dimensional input variables is proposed. Firstly, an arbitrary stochastic process simulation (ASPS) method based on Karhunen-Loève (K-L) expansion and numerical integration is developed, expressing the stochastic process as the combination of its marginal distributions and eigen functions at several discrete time points. Secondly, the iterative sorting method is implemented to the statistic samples of marginal distributions for matching the constraints of covariance function. Since marginal distributions are directly used to express the stochastic process, the proposed ASPS is suitable for stationary or non-stationary stochastic processes with arbitrary marginal distributions. Thirdly, the high-dimensional TUP problem is converted into several high-dimensional static uncertainty propagation (UP) problems after implementing ASPS. Then, the Bayesian deep neural network based UP method is used to compute the marginal distributions as well as the eigen functions of dynamic system response, the high-dimensional TUP problem can thus be solved. Finally, several numerical examples are used to validate the effectiveness of the proposed method. This article is part of the theme issue 'Physics-informed machine learning and its structural integrity applications (Part 1)'.

7.
Inorg Chem ; 61(29): 11218-11231, 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35834800

RESUMEN

Pt(II) complexes are promising phosphorescent materials for organic light-emitting diode (OLED) applications in the fields of display, lighting, healthcare, aerospace, and so on. A series of novel biphenyl (bp)-based tetradentate 6/5/6 Pt(II) emitters using oxygen or carbon as a linking atom was designed and developed. The intermolecular interactions in crystal packing, electrochemical, and photophysical properties of the bp-based Pt(II) emitters and also their excited-state properties were systematically studied, which could be effectively regulated by ligand modification through linking group control; however, their emission spectra nearly showed no change. All the bp-based Pt(II) emitters exhibited vibronically featured emission spectra with dominant peaks at 502-505 nm and photoluminescent quantum yields of 24-34% in dichloromethane solution. Green OLED using Pt(bp-12) as an emitter achieved a maximum brightness (Lmax) of 16,644 cd/m2.

8.
J Chem Phys ; 157(21): 214102, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36511544

RESUMEN

As popular mixed quantum-classical dynamics methods, trajectory surface hopping and Ehrenfest mean field have been widely utilized to simulate nonadiabatic dynamics. Recently, we have proposed the branching-corrected surface hopping and the branching-corrected mean field methods, both of which closely reproduce the exact quantum dynamics in a series of standard scattering models. Here, the mixed surface hopping and mean field with branching correction (BCSHMF) is presented as a unified framework of mixed quantum-classical dynamics. As benchmarked in thousands of diverse three-level and four-level scattering models, BCSHMF achieves high reliability and flexibility, implying that surface hopping and mean field are compatible with each other in nature, and trajectory branching is essential for the mixed quantum-classical description of nonadiabatic dynamics.

9.
J Chem Phys ; 156(11): 114116, 2022 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-35317594

RESUMEN

We present a new algorithm of the branching corrected mean field (BCMF) method for nonadiabatic dynamics [J. Xu and L. Wang, J. Phys. Chem. Lett. 11, 8283 (2020)], which combines the key advantages of the two existed algorithms, i.e., the deterministic BCMF algorithm based on weights of trajectory branches (BCMF-w) and the stochastic BCMF algorithm with random collapse of the electronic wavefunction (BCMF-s). The resulting mixed deterministic-stochastic BCMF algorithm (BCMF-ws) is benchmarked in a series of standard scattering problems with potential wells on the excited-state surfaces, which are common in realistic systems. In all investigated cases, BCMF-ws holds the same high accuracy while the computational time is reduced about two orders of magnitude compared to the original BCMF-w and BCMF-s algorithms, thus promising for nonadiabatic dynamics simulations of general systems.

10.
Inorg Chem ; 60(17): 12972-12983, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34374530

RESUMEN

A series of novel tetradentate Pt(II) and Pd(II) complexes containing fused 6/6/6 or 6/6/5 metallocycles employing azacarbazolylcarbazole (ACzCz)-based ligands was developed. Systematic experimental and theoretical studies suggest that both the ligand structures and the central metal ions have great influences on the electrochemical and photophysical properties of the complexes. The time-dependent density functional theory (TD-DFT) calculations and natural transition orbital (NTO) analyses reveal that the Pt(II) complexes possess 10.8-15.2% metal-to-ligand charge transfer (3MLCT) mixed with ligand-centered (3LC) characters, by contrast, the Pd(II) complexes exhibit significantly decreased 4.2-7.1% 3MLCT characters and enhanced 3LC compositions. All of the Pt(II) and Pd(II) complexes possess various channels for the intersystem crossing (ISC) on the basis of small energy gaps ΔES1-Tn and matching transition orbital compositions; moreover, Pd(ACzCz-1) and Pd(ACzCz-2) also possess efficient reverse intersystem crossing (RISC) to show both delayed fluorescence (DF) and phosphorescence in PMMA films at room temperature (RT). Pt(ACzCz-3) has ΦPL values of 57% with a τ of 5.1 µs in dichloromethane at RT and 50% with 3.9 µs in PMMA at RT. Notably, Pd(ACzCz-1) exhibits ultralong low-temperature phosphorescence with a τ of 1307 µs. Pt(ACzCz-2)-based green OLED employing 26mCPy as the host demonstrated a peak EQE of 8.2% and a Lmax of 24065 cd/m2.

11.
Inorg Chem ; 59(24): 18109-18121, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33241678

RESUMEN

A series of phenylpyridine (ppy)-based 6/5/5 N*C^N^O and biphenyl (bp)-based 6/5/6 N*C^C*N Pt(II) complexes employing tetradentate ligands with nitrogen or oxygen atoms as bridging groups have been developed. Ligand structural modifications have great influences on the electrochemical, photophysical, and excited-state properties, as well as photostabilities of the Pt(II) complexes, which were systematically studied by experimental and theoretical investigations. The time-dependent density functional theory calculations and natural transition orbital analyses reveal that Pt(bp-6), Pt(bp-7), and Pt(bp-8) have dominant ligand-centered (3LC) mixed with small metal-to-ligand charge-transfer (3MLCT) characters in T1 states, resulting in relatively low quantum efficiencies (ΦPL) of 5-33% and 12-32% in dichloromethane solution and PMMA film, respectively. By contrast, Pt(ppy-1) possesses much more 3MLCT character in the T1 state, enabling a high ΦPL of 95% in dichloromethane and 90% in DPEPO film, and large radiative decay rates. The strength of the Pt-N1 coordination bond plays a critical role in the photostability. Pt(ppy-1)- and Pt(bp-6)-doped polystyrene films demonstrate long photostability lifetimes of 150 min for LT97 and LT98.5, respectively. A Pt(ppy-1)-based green OLED using 26mCPy as host realized a peak EQE of 18.5%, which still maintained an EQE of 10.4% at 1000 cd/m2, and an Lmax of over 40 000 cd/m2 was achieved. This study should provide a valuable reference for the further development of efficient and stable phosphorescent Pt(II) complexes.

12.
Inorg Chem ; 59(6): 3718-3729, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32105064

RESUMEN

A series of neutral tetradentate Pt(II) complexes with fused 6/5/6 metallocycles and biphenyl (bp)-containing ligands have been designed and synthesized. All bridging atoms adopt nitrogens designed as an acridinyl group (Ac), an aza acridinyl group (AAc), and an aza carbazolyl group (ACz), which can effectively tune their LUMO energy levels. Their HOMO energy levels can be well-controlled through molecular modifications on the bp moieties with electron-donating and electron-withdrawing groups. These molecular modifications also have profound effects on the electrochemical and photophysical properties and photostabilities of the Pt(II) complexes. The ground-states and excited states are systematically studied by density functional theory (DFT), time-dependent density functional theory (TD-DFT), and natural transition orbital (NTO) calculations. All the Pt(II) complexes exhibit admixed 3(LC/MLCT) characters in T1 states with various proportions, which are strongly structure-dependent. These 6/5/6 Pt(II) complexes demonstrate high quantum efficiencies in dichloromethane solutions (ΦPL = 27-51%) and in doped PMMA films (ΦPL = 36-52%) at room temperature with short luminescence lifetimes of 1.6-9.5 µs and 7.6-9.0 µs, respectively. They emit green light with dominant peaks of 512-529 nm in solutions and 512-524 nm in doped PMMA films, respectively. Importantly, Pt(bp-2) exhibits highly stable emission colors with the same dominant peaks at 512 nm in various matrixes and also demonstrates a long photostability lifetime, LT80, at 80% of initial luminance, of 190 min, which is doped in polystyrene films (5 wt %) excited by UV light of 375 nm at 500 W/m2. These studies indicate that these 6/5/6 Pt(II) complexes can act as good phosphorescent emitters for OLED applications and should provide a viable route for the development of efficient and stable Pt(II)-based phosphorescent emitters.

13.
Inorg Chem ; 59(18): 13502-13516, 2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32869994

RESUMEN

Deep-blue-light-emitting materials are urgently desired in high-performance organic light-emitting diodes (OLEDs) for full-color display and solid-state lighting applications. However, the development of stable and efficient deep-blue emitters remains a great challenge. Herein, a series of stable and efficient tetradentate Pd(II)-complex-based deep-blue emitters with rigid 5/6/6 metallocycles and no F atom were designed and synthesized. These deep-blue emitters employ various isoelectronic five-membered heteroaryl-ring-containing ligands to exhibit extremely narrow emission spectra peaking at 439-443 nm with a full width at half-maximum (fwhm) of only 22-38 nm in 2-methyltetrahydrofuran at room temperature. In particular, the design of an intramolecular hydrogen bond enabled the 1-phenyl-1,2,3-trazole-based Pd(II) complexes to achieve CIEy < 0.1 (0.069-0.078; CIE is Commission Internationale de L'Eclairage). Theoretical calculation and natural transition orbital analysis reveal that these deep-blue materials emit light exclusively from their ligand (carbazole)-centered (3LC) states. Moreover, the triplet excited-state property can be efficiently regulated through ligand modification with isoelectronic oxazole and thiazole rings or pyridine rings, resulting in sky-blue-to-yellow materials, which emit light originating from an admixture of metal-to-ligand charge-transfer (3MLCT) and intraligand charge-transfer states. The newly developed Pd(II) complexes are strongly emissive in various matrixes with a quantum efficiency of up to 51% and also highly thermally stable with a 5% weight-reduction temperature (ΔT5%) of up to 400 °C. Deep-blue OLEDs with CIEy < 0.1 employing Pd(II) complexes as emitters were successfully fabricated for the first time. This study demonstrates that the Pd(II) complexes can act as excellent phosphorescent light-emitting materials through rational molecular design and also provide a valuable method for the development of Pd(II)-complex-based efficient and stable deep-blue emitters.

14.
Org Biomol Chem ; 18(2): 346-352, 2020 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-31845954

RESUMEN

The mechanism and origin of the stereoselectivity of asymmetric benzylic C-H hydroxylation by Ru-porphyrin were elucidated with density functional theory calculations. The reaction proceeds via a hydrogen-atom abstraction/oxygen-rebound pathway, wherein a high-valent ruthenium-oxo species abstracts a hydrogen atom from ethylbenzene to generate a radical pair intermediate, followed by the oxygen-rebound process to form 1-phenylethanol. The hydrogen-atom abstraction step is the rate- and stereoselectivity-determining step. Based on the mechanistic model, the computed stereoselectivity is in agreement with the experimental observations. Analysis of the distortion/interaction model suggests that stereoselectivity is determined by both the distortion energy of the ethylbenzene and the interaction energy between the ethylbenzene and the chiral Ru-porphyrin. The steric repulsion between the phenyl group of ethylbenzene and the bulky substituent of Ru-porphyrin is the leading cause of chiral induction.

15.
J Sci Food Agric ; 100(4): 1470-1478, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31756278

RESUMEN

BACKGROUND: The egg yolk is complex, which makes it difficult to understand why mayonnaise can be stabilized into a high internal-phase emulsion. This study aimed to assess the possibility of developing oil-in-water emulsions through unmodified natural egg-yolk granules (EYGs) at various pH levels, to further understand the precise mechanism of mayonnaise. RESULTS: Egg-yolk granules were obtained from hen egg yolk by centrifugation. The sizes of the EYGs were characterized using dynamic light scattering (DLS). Zeta potential of EYGs was detected by DLS and its microstructure was observed by microscope and scanning electron microscope (SEM). Oil / water emulsions were made with EYGs and the size distribution and creaming index of those emulsions were measured at different storage times (1 h and 14 days). The interfacial morphology of EYGs was observed using the emulsion polymerization method. Our results suggested that the prepared EYGs were mainly in an aggregated state but individual EYGs displayed spherical shapes, with a size of 1.0 ± 0.2 µm. The emulsion stabilized by EYGs displayed better stability against creaming at acidic pH (<4.0). At the same time, the interfacial morphology and microscopic observation of the emulsions strongly demonstrated that the emulsions were of the Pickering type. CONCLUSION: The above results are of great importance for an understanding of the mechanism by which mayonnaise is stabilized by egg, together with the applications of egg in food formulations. © 2019 Society of Chemical Industry.


Asunto(s)
Yema de Huevo/química , Emulsiones/química , Animales , Pollos , Concentración de Iones de Hidrógeno , Aceites/química , Tamaño de la Partícula
16.
J Org Chem ; 84(21): 13755-13763, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31599588

RESUMEN

The mechanism and origins of stereoselectivity of chiral iron porphyrin-catalyzed asymmetric hydroxylation of ethylbenzene were explored with density functional theory. The hydrogen atom abstraction is the rate- and stereoselectivity-determining step. In good agreement with experimental results, the formation of the (R)-1-phenylethanol product is found to be the most favorable pathway. The transition state of hydrogen atom abstraction which leads to the (S)-1-phenylethanol product is unfavorable by 1.7 kcal/mol compared to the corresponding transition state which leads to the (R)-1-phenylethanol product. Enantioselectivity arises from an attractive π-π stacking interaction between the phenyl group of ethylbenzene substrate and the naphthyl group of the porphyrin ligand.

17.
Inorg Chem ; 58(21): 14349-14360, 2019 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-31498601

RESUMEN

The synthesis and photophysical characterization of a series of tetradentate cyclometalated M(tzpPh-O-CzPy-R) complexes and their analogues are reported, where M is palladium or platinum and a tetradentate cyclometalating ligand contains tzpPh (3-phenyl-[1,2,4]triazolo[4,3-a]pyridine) and CzPy (carbazolylpyridine) moieties linked with an oxygen atom. Variations of the σ-electron-donating group R on the ligand significantly affect the photophysical properties of the complexes. By using the strong electron-withdrawing tzp portion as an acceptor and the carbazole portion as a donor, a series of Pd(II)-based metal-assisted delayed fluorescence (MADF) materials was developed. Electrochemical analysis demonstrates the irreversible reduction process occurs on the tzp ring and the irreversible oxidation process mainly occurs on the metal-phenyl moiety. This is in agreement with the HOMO and LUMO distributions by the DFT calculations, which also shows that the Pt(II) complex has more metal orbital character than those of the Pd(II) complexes. Most of the Pd(II) complexes reported here are highly emissive at 77 K in 2-MeTHF with luminescent lifetimes in the millisecond range (τ = 1.96-2.36 ms) and λmax = 488-499 nm; however, the luminescent lifetimes are shortened to the microsecond range (τ = 26.7-152.9 µs in solution and 57.0-109.9 µs in thin film respectively) at room temperature. The quantum efficiency of the Pd(II) complexes can be increased by more than 8-fold through structure modification with σ-donating groups on the ligand. Especially, the Pd(tzp-3) has a small ΔEST of 0.228 eV and exhibits strong typical MADF in PMMA film. The Pt(II) complex Pt(tzp-2) exhibits high thermal stability (ΔT0.5% = 440 °C) and high quantum efficiency (Φ = 50.1%) in dichloromethane solution with τ of 15.8 µs. The Pt(tzp-2) based bright green OLED achieved a peak EQE of 8.7% and a maximum brightness of 28280 cd/m2 using an unoptimized device structure.

18.
Inorg Chem ; 58(9): 5725-5732, 2019 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-31021615

RESUMEN

Metal-organic frameworks (MOFs) are a class of advanced porous crystalline materials. However, numerous MOFs have poor chemical stability, significantly restricting their industrial application. The introduction of trifluoromethyl groups around clusters of MOFs results in a shielding effect caused by their hydrophobicity and bulkiness, thus preventing guest molecules from attacking the coordination bonds. To prove such a shielding effect, the position of the trifluoromethyl groups is rationally adjusted, with trifluoromethyl groups at the ortho positions of carboxyl groups significantly improving the chemical stability of UiO-67. The prepared UiO-67- o-2CF3 remains intact after treatment with boiling water, 8 M HCl, 10 mM NaOH, and 50 ppm of NaF aqueous solutions. As the control experiment, trifluoromethyl groups at the meta positions of carboxyl groups have no shielding effect; hence, UiO-67- m-2CF3 has a stability that is lower than that of UiO-67- o-2CF3. In addition, the shielding effect is also applied to other MOFs, including DUT-5- o-2CF3 and Al-TPDC- o-2CF3, confirming the universality of this strategy.

19.
J Dairy Sci ; 102(1): 26-36, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30527985

RESUMEN

The present study investigated the effects of Lactobacillus plantarum YS2 (LP-YS2) that was isolated from yak yogurt on activated carbon-induced constipation in Kunming (KM) mice. The KM mice were orally administered LP-YS2 and reference strain Lactobacillus delbrueckii ssp. bulgaricus. Administration of LP-YS2 [1.0 × 109 cfu/kg of body weight (BW)] promoted gastrointestinal peristalsis and reduced the first black stool defecation time (129 min), which clearly defines attenuation of the voiding difficulty in mice with constipation. The LP-YS2 treatment also increased the serum level of motilin (MTL; 178.2 pg/mL), gastrin (69.4 pg/mL), acetylcholine (Ach; 30.1 pg/mL), substance P (SP; 57.6 pg/mL), and vasoactive intestinal peptide (VIP; 53.2 pg/mL) and reduced the somatostatin (SS, 32.6 pg/mL) levels compared with the L. delbrueckii ssp. bulgaricus treatment (MTL, 139.7 pg/mL; gastrin, 43.1 pg/mL; Ach, 15.9 pg/mL; SP, 43.6 pg/mL; VIP, 32.3 pg/mL; SS, 55.1 pg/mL) and the control (MTL, 105.3 pg/mL; gastrin, 26.7 pg/mL; Ach, 9.7 pg/mL; SP, 30.2 pg/mL; VIP, 21.0 pg/mL; SS, 70.5 pg/mL). The LP-YS2 treatment significantly increased the colonic mRNA and protein expression of c-Kit (CD117, cluster of differentiation 117; 2.87 times mRNA expression of the control group), stem cell factor (30.40 times mRNA expression of the control group), and glial cell-derived neurotrophic factor (29.97 times mRNA expression of the control group) in mice with constipation. In addition, LP-YS2 reduced the expression of transient receptor potential vanilloid 1 (0.42 times mRNA expression of the control group) and nitric oxide synthase (0.49 times mRNA expression of the control group) in constipated mice. These results demonstrate that LP-YS2 was able to attenuate the activated carbon-induced constipation in KM mice.


Asunto(s)
Estreñimiento/prevención & control , Lactobacillus plantarum/metabolismo , Yogur/microbiología , Animales , Antioxidantes/análisis , Biomarcadores/análisis , Peso Corporal , Bovinos , Carbón Orgánico/efectos adversos , Colon/metabolismo , Estreñimiento/inducido químicamente , Estreñimiento/terapia , Defecación , Tracto Gastrointestinal/metabolismo , Tránsito Gastrointestinal/fisiología , Intestino Delgado/metabolismo , Lactobacillus delbrueckii/metabolismo , Masculino , Ratones , Óxido Nítrico Sintasa/metabolismo , Peristaltismo/fisiología , Sustancia P/metabolismo
20.
J Cell Biochem ; 119(1): 511-523, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28608558

RESUMEN

Objective A network meta-analysis was conducted to compare the efficacy and toxicity of different chemotherapy regimens in treating advanced or metastatic pancreatic cancer (PC). PubMed, Cochrane Library and EMBASE databases from inception to June 2016 were searched. A combination of direct and indirect evidences was referred to for calculating the weighted mean difference (WMD) or the odds ratio (OR) and to establish surface under the cumulative ranking (SUCRA) curves, so as to evaluate the efficacy and toxicity of different chemotherapy regimens in treating advanced or metastatic PC. Twenty randomized controlled trials were enrolled. Twelve chemotherapy regimens included Gemcitabine, S-1 (Tegafur), Gemcitabine + Cisplatin, Gemcitabine + Capecitabine, Gemcitabine + S-1, Gemcitabine + 5-FU (5-fluorouracil), Gemcitabine + Exatecan, Gemcitabine + Irinotecan, Gemcitabine + Nab-paclitaxel, FOLFIRINOX (Oxaliplatin + Irinotecan + Fluorouracil + Leucovorin), Gemcitabine + Oxaliplatin, and Gemcitabine + Pemetrexed. Higher overall response rate (ORR) was observed in patients treated with the gemcitabine + S-1 and FOLFIRINO regimens. Thrombocytopenia reduced in patients treated with the S-1 regimen. The Gemcitabine + S-1 and FOLFIRINO regimens had better short- and long-term efficacies than the other regimens; S-1 regimen had the lowest hematologic toxicity, while Gemcitabine + Nab-paclitaxel, FOLFIRINOX, and Gemcitabine + Pemetrexed regimens had higher incidence of non-hematologic toxicity among twelve chemotherapy regimens. The efficacy of Gemcitabine + S-1 and FOLFIRINOX regimens may be better in treating patients with advanced or metastatic pancreatic cancer, while FOLFIRINOX and Gemcitabine + Pemetrexed regimens may have relatively higher incidence of toxicity than other regimens. J. Cell. Biochem. 119: 511-523, 2018. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Femenino , Humanos , Masculino , Metástasis de la Neoplasia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología
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