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1.
Clin Case Rep ; 12(2): e8474, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38344344

RESUMO

We report a case of leukemia cutis showing annular erythema during the course of Philadelphia chromosome-positive acute B-lymphoblastic leukemia. The annular appearance may be developed by immunomodulatory effects of blinatumomab.

2.
Nat Commun ; 15(1): 425, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267420

RESUMO

Alkali metal (AM) intercalation between graphene layers holds promise for electronic manipulation and energy storage, yet the underlying mechanism remains challenging to fully comprehend despite extensive research. In this study, we employ low-voltage scanning transmission electron microscopy (LV-STEM) to visualize the atomic structure of intercalated AMs (potassium, rubidium, and cesium) in bilayer graphene (BLG). Our findings reveal that the intercalated AMs adopt bilayer structures with hcp stacking, and specifically a C6M2C6 composition. These structures closely resemble the bilayer form of fcc (111) structure observed in AMs under high-pressure conditions. A negative charge transferred from bilayer AMs to graphene layers of approximately 1~1.5×1014 e-/cm-2 was determined by electron energy loss spectroscopy (EELS), Raman, and electrical transport. The bilayer AM is stable in BLG and graphite superficial layers but absent in the graphite interior, primarily dominated by single-layer AM intercalation. This hints at enhancing AM intercalation capacity by thinning the graphite material.

3.
ACS Nano ; 16(9): 14075-14085, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-35921093

RESUMO

Bilayer graphene (BLG) has a two-dimensional (2D) interlayer nanospace that can be used to intercalate molecules and ions, resulting in a significant change of its electronic and magnetic properties. Intercalation of BLG with different materials, such as FeCl3, MoCl5, Li ions, and Ca ions, has been demonstrated. However, little is known about how the twist angle of the BLG host affects intercalation. Here, by using artificially stacked BLG with controlled twist angles, we systematically investigated the twist angle dependence of intercalation of metal chlorides. We discovered that BLG with high twist angles of >15° is more favorable for intercalation than BLG with low twist angles. Density functional theory calculations suggested that the weaker interlayer coupling in high twist angle BLG is the key for effective intercalation. Scanning transmission electron microscope observations revealed that co-intercalation of AlCl3 and CuCl2 molecules into BLG gives various 2D structures in the confined interlayer nanospace. Moreover, before intercalation we observed a significantly lower sheet resistance in BLG with high twist angles (281 ± 98 Ω/□) than that in AB stacked BLG (580 ± 124 Ω/□). Intercalation further decreased the sheet resistance, reaching values as low as 48 Ω/□, which is the lowest value reported so far for BLG. This work provides a twist angle-dependent phenomenon, in which enhanced intercalation and drastic changes of the electrical properties can be realized by controlling the stacking angle of adjacent graphene layers.

4.
JA Clin Rep ; 8(1): 10, 2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35150377

RESUMO

BACKGROUND: In robot-assisted laparoscopic prostatectomy (RALP), concerns include the formation of atelectasis and reduced functional residual capacity. The present study aimed to examine the feasibility of positive end-expiratory pressure (PEEP) setting based on transpulmonary pressure (Ptp) as well as the effects of incremental PEEP on respiratory mechanics, blood gases, cerebral oxygenation (rSO2), and hemodynamics. METHODS: Fourteen male patients who were scheduled to receive RALP were recruited. Patients received mechanical ventilation (tidal volume of 6 mL kg-1) and were placed in Trendelenburg position with positive-pressure capnoperitoneum. PEEP levels were increased from 0 to 15 cmH2O (5 cmH2O per increase) every 30 min. PEEP levels were assessed where end-expiratory Ptp levels of ≥0 cmH2O were achieved (PtpEEP0). Airway pressure, esophageal pressure, cardiac index, and blood gas and rSO2 values were measured after 30 min at each PEEP step and respiratory mechanics were calculated. RESULTS: With increasing PEEP levels from 0 to 15 cmH2O or PtpEEP0, the values of PaO2 and respiratory system compliance increased, and the values of driving pressure decreased. The median PEEP level associated with PtpEEP0 was 15 cmH2O. Respiratory system compliance values were higher at PtpEEP0 than those at PEEP5 (P = 0.02). Driving pressure was significantly lower at PtpEEP0 than at PEEP5 (P = 0.0036). The cardiac index remained unchanged, and the values of rSO2 were higher at PtpEEP0 than at PEEP0 (right; P = 0.0019, left; P = 0.036). CONCLUSIONS: PEEP setting determined by transpulmonary pressure can help achieve higher respiratory system compliance values and lower driving pressure without disturbing hemodynamic parameters.

5.
Nano Lett ; 21(24): 10386-10391, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34881904

RESUMO

We studied the interlayer coupling and decoupling of bilayer graphene (BLG) using spatially resolved electron energy loss spectroscopy with a monochromated electron source. We correlated the twist-angle-dependent energy band hybridization with Moiré superlattices and the corresponding optical absorption peaks. The optical absorption peak originates from the excitonic transition between the hybridized van Hove singularities (vHSs), which shifts systematically with the twist angle. We then proved that the BLG decouples when a monolayer of metal chloride is intercalated in its van der Waals gap and results in the elimination of the vHS peak.

6.
Adv Mater ; 29(41)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28922479

RESUMO

Bilayer graphene (BLG) comprises a 2D nanospace sandwiched by two parallel graphene sheets that can be used to intercalate molecules or ions for attaining novel functionalities. However, intercalation is mostly demonstrated with small, exfoliated graphene flakes. This study demonstrates intercalation of molybdenum chloride (MoCl5 ) into a large-area, uniform BLG sheet, which is grown by chemical vapor deposition (CVD). This study reveals that the degree of MoCl5 intercalation strongly depends on the stacking order of the graphene; twist-stacked graphene shows a much higher degree of intercalation than AB-stacked. Density functional theory calculations suggest that weak interlayer coupling in the twist-stacked graphene contributes to the effective intercalation. By selectively synthesizing twist-rich BLG films through control of the CVD conditions, low sheet resistance (83 Ω â–«-1 ) is realized after MoCl5 intercalation, while maintaining high optical transmittance (≈95%). The low sheet resistance state is relatively stable in air for more than three months. Furthermore, the intercalated BLG film is applied to organic solar cells, realizing a high power conversion efficiency.

8.
Insect Biochem Mol Biol ; 37(9): 960-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17681235

RESUMO

A cysteine protease inhibitor (CPI) with an apparent molecular mass of 11.5kDa was purified from larval hemolymph of the tobacco hornworm (Manduca sexta) by gel filtration on Sephadex G-50 followed by hydrophobic and ion-exchange column chromatographies. The purified cysteine proteinase inhibitor, denoted as MsCPI, strongly inhibited the plant cysteine protease, papain, with a K(i) value of 5.5 x 10(-9)M. Nucleotide sequence analysis of a partial cDNA encoding MsCPI indicated that MsCPI consists of 105 amino acid residues in a sequence that is similar to sarcocystatin A from Sarcophaga peregrina. However, northern blotting and PCR analyses using the specific primers of MsCPI suggested that the mRNA encoding MsCPI had a size of more than 12 kilobases, which included at least six tandemly repeated MsCPI segments. MsCPI was expressed in Escherichia coli and the recombinant protein effectively inhibited cysteine proteases from plants as well as from animals such as cathepsins B (K(i), 6.8 nM), H (3.0 nM), and L (0.87 nM). There was no inhibition exhibited toward trypsin, chymotrypsin, subtilisin, pepsin or themolysin.


Assuntos
Inibidores de Cisteína Proteinase/isolamento & purificação , Hemolinfa/química , Manduca/crescimento & desenvolvimento , Sequência de Aminoácidos , Animais , Catepsinas/efeitos dos fármacos , Catepsinas/isolamento & purificação , Catepsinas/metabolismo , Clonagem Molecular , Sequência Conservada , Inibidores de Cisteína Proteinase/genética , Inibidores de Cisteína Proteinase/farmacologia , Primers do DNA , Escherichia coli/genética , Humanos , Larva , Dados de Sequência Molecular , Papaína/antagonistas & inibidores , Reação em Cadeia da Polimerase , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
9.
J Am Chem Soc ; 127(45): 15891-9, 2005 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-16277532

RESUMO

The shuttling process of alpha-CyD in three rotaxanes (1-3) containing alpha-cyclodextrin (alpha-CyD) as a ring, azobenzene as a photoactive group, viologen as an energy barrier for slipping of the ring, and 2,4-dinitrobenzene as a stopper was investigated. The trans-cis photoisomerization of 1 by UV light irradiation occurred in both DMSO and water due to the movement of alpha-CyD toward the ethylene group, while the photoisomerization of 2 occurred in DMSO, but not in water. No photoisomerization was observed for 3 in both water and DMSO. The activation parameters of 1 and 1-ref in DMSO are subject to a compensation relation between deltaS(double dagger) and deltaH(double dagger); however, in water, the deltaS(double dagger) terms are not compensated by the deltaH(double dagger) terms. Alternating irradiation of the UV and visible lights resulted in a reversible change in the induced circular dichroism (ICD) bands of trans-1 and cis-1. In contrast, after the UV light irradiation, the ICD band of trans-2 decreased without the appearance of any bands of cis-2. The NMR spectra of 2 in DMSO showed coalescence of the split signals for the methylene and for the viologen protons due to the shuttling of alpha-CyD. Both the NOE differential spectra for cis-1 in water after UV light irradiation and 2 in DMSO after heating to 120 degrees C showed the negative NOE peaks assigned to interior protons of alpha-CyD, suggesting that alpha-CyD in cis-1 exists at the one ethylene moiety, and alpha-CyDs in cis-2 and 2 heated in DMSO exist at the propylene moieties.

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