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Nowadays, oral medications are the primary method of treating disease due to their convenience, low cost, and safety, without the need for complex medical procedures. To maximize treatment effectiveness, almost all oral medications utilize drug carriers, such as capsules, liposomes, and sugar coatings. However, these carriers rely on dissolution or fragmentation to achieve drug release, which leads to drugs and carriers coabsorption in the body, causing unnecessary adverse drug reactions, such as nausea, vomiting, abdominal pain, and even death caused by allergy. Therefore, the ideal oral drug carrier should avoid degradation and absorption and be totally excreted after drug release at the desired location. Herein, a gastrointestinally stable oral drug carrier based on porous aromatic framework-1 (PAF-1) is constructed, and it is modified with famotidine (a well-known gastric drug) and mesalazine (a well-known ulcerative colitis drug) to verify the excellent potential of PAF-1. The results demonstrate that PAF-1 can accurately release famotidine in stomach, mesalazine in the intestine, and finally be completely excreted from the body without any residue after 12 h. The use of PAF materials for the construction of oral drug carriers with no residue in the gastrointestinal tract provides a new approach for efficient disease treatment.
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Polymers under nanoconfinement can exhibit large alterations in dynamics from their bulk values due to an interface effect. However, understanding the interface effect remains a challenge, especially in the ultrafine nanoconfinement region. In this work, we prepare new geometries with ultrafine nanoconfinement â¼10nm through controlled distributions of the crystalline phases and the amorphous phases of a model semi-crystalline polymer, i.e., the polylactic acid. The broadband dielectric spectroscopy measurements show that ultrafine nanoconfinement leads to a large elevation in the glass transition temperature and a strong increment in the polymer fragility index. Moreover, new relaxation time profile analyses demonstrate a spatial gradient that can be well described by either a single-exponential decay or a double-exponential decay functional form near the middle of the film with a collective interface effect. However, the dynamics at the 1-2 nm vicinity of the interface exhibit a power-law decay that is different from the single-exponential decay or double-exponential decay functional forms as predicted by theories. Thus, these results call for further investigations of the interface effect on polymer dynamics, especially for interfaces with perturbed chain packing.
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The detection technology of infrared polarization has gained significant attention due to its ability to provide better identification and obtain more information about the target. In this paper, based on the expression of the full polarization state in Stokes space, we designed micro-nano metasurface functional arrays to calculate the polarization state of the incident light by reading the Stokes parameters (a set of parameters that describe the polarization state). Metalens with linear and circular polarization-dependent functions are designed based on the propagation and geometric phases of the dielectric Si meta-atoms in the infrared band, respectively. The device exhibits a high polarization extinction ratio. The influence of incident angle on polarization-dependent metalens is discussed, and the analysis of incident angle is of great significance for the practical application. An infrared six-foci metalens is proposed, each corresponding to the Poincaré sphere's coordinate component (a graphical polarization state method). By matching the six polarization components of the incident light and the Stokes parameters, the polarization detection function can be realized by calculating the polarization state of the incident light. There is a slight error between the theoretical value and the calculated value of the unit coordinate component of the Stokes parameters. At the same time, the intensity distribution of different incident light polarization azimuth angles and ellipticity angles on the focal plane agrees with the theory. The advantage of the device is that the polarization state of the incident light can be directly calculated without passing through other components. The six-foci metalens have potential applications in polarization detection and imaging, space remote sensing, etc.
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Polarization and focal length are both critical optical parameters with many applications in many fields, such as optical communications and imaging. The development of metasurfaces provides a new realization of optical systems. In this paper, based on metasurfaces' powerful electromagnetic modulation capability, we integrate polarization conversion with continuous zoom function and propose a dynamic polarization-regulated metasurface with variable focal length. It realizes the reversible conversion of polarization state, which can convert linearly polarized light into elliptically polarized light and circularly polarized light and convert circularly polarized light to linearly polarized light. At the same time, it achieves a 4.4× zoom range, with a constant focal length variation from 70â µm to 309â µm. The metasurface has the advantages of small size, easy integration, and reconfigurability, providing a new design idea for complex functional optical systems.
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The absorption spectrum of metasurface absorbers can be manipulated by changing structures. However, narrowband performance absorbers with high quality factors (Q-factor) are hard to achieve, mainly for the ohmic loss of metal resonators. Here, we propose an all-dielectric metasurface absorber with narrow absorption linewidth in the mid-infrared range. Magnetic quadrupole resonance is excited in the stacked Ge-Si3N4 nanoarrays with an absorption of 89.6% and a Q-factor of 6120 at 6.612â µm. The separate lossless Ge resonator and lossy Si3N4 layer realize high electromagnetic field gain and absorption, respectively. And the proposed method successfully reduced the intrinsic loss of the absorber, which reduced the absorption beyond the resonant wavelength and improved the absorption efficiency of Si3N4 in the low loss range. Furthermore, the absorption intensity and wavelength can be modulated by adjusting the geometric parameters of the structure. We believe this research has good application prospects in mid-infrared lasers, thermal emitters, gas feature sensing, and spectral detection.
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Circularly polarized light (CPL) finds diverse applications in fields such as quantum communications, quantum computing, circular dichroism (CD) spectroscopy, polarization imaging, and sensing. However, conventional techniques for detecting CPL face challenges related to equipment miniaturization, system integration, and high-speed operation. In this study, we propose a novel design that addresses these limitations by employing a quarter waveplate constructed from a diamond metasurface, in combination with a linear polarizer crafted from metallic aluminum. The diamond array, with specific dimensions (a = 84â nm, b = 52â nm), effectively transforms left-handed and right-handed circularly polarized light into two orthogonally linearly polarized beams who have a polarization degree of approximately 0.9. The aluminum linear polarizer then selectively permits the transmission of these transformed linearly polarized beams.Our proposed design showcases remarkable circular dichroism performance at a wavelength of 280â nm, concurrently maintaining high transmittance and achieving a substantial extinction ratio of 25. Notably, the design attains an ultraviolet wavelength transmission efficiency surpassing 80%. Moreover, our design incorporates a rotation mechanism that enables the differentiation of linearly polarized light and singly circularly polarized light. In essence, this innovative design introduces a fresh paradigm for ultraviolet circularly polarized light detection, offering invaluable insights and references for applications in polarization detection, imaging, biomedical diagnostics, and circular dichroic spectroscopy.
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We provide a method to regulate intramolecular charge transfer (ICT) through distorting fragment dipole moments based on molecular planarity and intuitively investigate the physical mechanisms of one-photon absorption (OPA), two-photon absorption (TPA), and electron circular dichroism (ECD) properties of the multichain 1,3,5 triazine derivatives o-Br-TRZ, m-Br-TRZ, and p-Br-TRZ containing three bromobiphenyl units. As the position of the C-Br bond on the branch chain becomes farther away, the molecular planarity is weakened, with the position of charge transfer (CT) on the branch chain of bromobiphenyl changing. The excitation energy of the excited states decreases, which leads to the redshift of the OPA spectrum of 1,3,5-triazine derivatives. The decrease in molecular plane results in a change in the magnitude and direction of the molecular dipole moment on the bromobiphenyl branch chain, which weakens the intramolecular electrostatic interaction of bromobiphenyl branch chain 1,3,5-triazine derivatives and weakens the charge transfer excitation of the second step transition in TPA, leading to an increase in the enhanced absorption cross-section. Furthermore, molecular planarity can also induce and regulate chiral optical activity through changing the direction of the transition magnetic dipole moment. Our visualization method helps to reveal the physical mechanism of TPA cross-sections generated via third-order nonlinear optical materials in photoinduced CT, which is of great significance for the design of large TPA molecules.
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Broadband perfect infrared wave absorption of unpolarized light over a wide range of angles in an ultrathin film is critical for applications such as thermal emitters and imaging. Although many efforts have been made in infrared broadband absorption, it is still challenging to cover the perfect absorption of broadband in the long-wave infrared band. We propose a long-wave infrared broadband, polarization, and incident angle insensitivity metamaterial absorber based on the supercell with four rings of two sizes. Broadband absorption covering the long-wave infrared band is realized by combining four PSPRs and LSPRs absorption peaks excited by the supercell structure. The absorptivity of our absorber exceeds 90% in the wavelength range of 7.76â¼14µm, and the average absorptivity reaches 93.8%. The absorber maintains more than 80% absorptivity as the incident angle of unpolarized light reaches 60°, which may have promising applications for thermal emitters, infrared imaging, thermal detection.
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To investigate the effects of leonurine(Leo) on abdominal aortic constriction(AAC)-induced cardiac hypertrophy in rats and its mechanism. A rat model of pressure overload-induced cardiac hypertrophy was established by AAC method. After 27-d intervention with high-dose(30 mg·kg~(-1)) and low-dose(15 mg·kg~(-1)) Leo or positive control drug losartan(5 mg·kg~(-1)), the cardiac function was evaluated by hemodynamic method, followed by the recording of left ventricular systolic pressure(LVSP), left ventricular end-diastolic pressure(LVESP), as well as the maximum rate of increase and decrease in left ventricular pressure(±dp/dt_(max)). The degree of left ventricular hypertrophy was assessed based on heart weight index(HWI) and left ventricular mass index(LVWI). Myocardial tissue changes and the myocardial cell diameter(MD) were measured after hematoxylin-eosin(HE) staining. The contents of angiotensin â ¡(Angâ ¡) and angiotensin â ¡ type 1 receptor(AT1 R) in myocardial tissue were detected by ELISA. The level of Ca~(2+) in myocardial tissue was determined by colorimetry. The protein expression levels of phospholipase C(PLC), inositol triphosphate(IP3), Angâ ¡, and AT1 R were assayed by Western blot. Real-time quantitative PCR(qRT-PCR) was employed to determine the mRNA expression levels of ß-myosin heavy chain(ß-MHC), atrial natriuretic factor(ANF), Angâ ¡, and AT1 R. Compared with the model group, Leo decreased the LVSP, LVEDP, HWI, LVWI and MD values, but increased ±dp/dt_(max) of the left ventricle. Meanwhile, it improved the pathological morphology of myocardial tissue, reduced cardiac hypertrophy, edema, and inflammatory cell infiltration, decreased the protein expression levels of PLC, IP3, Angâ ¡, AT1 R, as well as the mRNA expression levels of ß-MHC, ANF, Angâ ¡, AT1 R, c-fos, and c-Myc in myocardial tissue. Leo inhibited AAC-induced cardiac hypertrophy possibly by influencing the RAS system.
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Cardiomegalia , Hipertrofia Ventricular Esquerda , Angiotensina II/metabolismo , Animais , Cardiomegalia/etiologia , Cardiomegalia/genética , Ácido Gálico/análogos & derivados , Hipertrofia Ventricular Esquerda/metabolismo , Hipertrofia Ventricular Esquerda/patologia , Miocárdio/patologia , RatosRESUMO
In this paper, the free Phospholipase A1 (PLA1) was immobilized on a magnetic carrier. The average particle diameter of the magnetic carrier was 97 ± 1.3 nm, and the average particle diameter of the magnetically immobilized PLA1 was 105 nm ± 1.3 nm. The enzyme activity was 1940.5 U/g. The magnetic enzyme was chemically modified with formaldehyde, dextran-aldehyde, and dextran-aldehyde-glycine. The proportions of primary amino groups in the modified magnetic immobilized enzyme PLA1 were 0, 53.5% and 47.3%, respectively. The optimum pH of the enzyme after chemical modification was 6.5. When the system temperature was 60 °C, the magnetically immobilized PLA1 modified with dextran-aldehyde-glycine had the optimal activity and stability. This chemically modified magnetic immobilized PLA1 was applied to soybean oil degumming at 60 °C, 6.5 h (reaction time), and 0.10 mg/kg (enzyme dosage). The phosphorus content in the degummed oil was 9.2 mg/kg. The relative enzyme activity was 77.6% after 7 reuses which would be potentially advantageous for industrial applications. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at (10.1007/s13197-021-05017-4).
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We report the development of bifunctional trifluoromethylsilyl reagents for selective trifluoromethylation. The newly developed reagent, Me2 (CH2 Cl)SiCF3 , allows highly enantioselective trifluoromethylations of ketones with broad scope. Notably, by taking advantage of the chloromethyl group, a tandem synthesis of chiral trifluoromethylated oxasilacyclopentanes is developed, paving way to α-CF3 tertiary alcohols with vicinal tertiary or quaternary stereocenters. Theoretical studies revealed the important role of nonclassical C-Hâ â â F-C interactions in stabilizing the transition state, and that the presence of the chlorine atom enhances such interactions for better enantiofacial control.
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Broadband absorption is critical for the applications of metamaterial absorbers. In this work, a broadband long-wave infrared (LWIR) absorber with classical metal-dielectric-metal configuration is numerically demonstrated. The absorber consists of single-sized cut-wire arrays that show broadband and high extinction ratio, attributed to polarization-selective simultaneous excitation of propagated and localized surface plasmon resonances. The average absorption rate of the TM wave reaches 91.7% and 90% of the incident light is absorbed by the resonator in the wavelength range of 7.5-13.25µm so that the average extinction ratio in the resonator layer reaches 125. The polarization insensitive broadband absorption can be obtained by a cross resonator which can be treated as a pair of cut-wires perpendicular to each other. Our metamaterial absorber with single-sized resonators shows spatially concentrated broadband absorption and may have promising applications for hot-electron devices, infrared imaging, and thermal detection.
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The atmospheric window in the infrared (IR) band primarily consists of mid-wave (MWIR, 3-5 µm) and long-wave IR (LWIR, 8-12 µm) bands, also known as the working bands in most of the IR devices. The main factor affecting the device capability includes the absorption efficiency, hence, the absorption material. Herein, a dual-band absorber based on the composite cross structure (CCS) in both MWIR and LWIR bands was proposed, with absorption peaks of 4.28 µm and 8.23 µm. The obtained absorber is with high scalability in the MWIR and LWIR region respectively by tuning the structural parameters. A quadrupole polarization model is proposed for further understanding of the uneven distribution of electromagnetic field that was caused by the change of the center spacing of the embedded structure. Meanwhile, it was shown that the two absorption peaks exhibited good incident angle stability. In addition, as the incident angle of the TM mode increases, a waveguide is formed between the embedded structure and the surface structure, leading to another strong absorption in the LWIR band. The results showed that absorption increases as the incident angle increases. The proposed absorber can be a good candidate for applications in thermal emission, detection and solar energy harvesting.
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α-Lactalbumin (α-LA) and ß-lactoglobulin (ß-LG) were isolated from yak milk and identified by mass spectrometry. The variant of α-LA (L8IIC8) in yak milk had 123 amino acids, and the sequence differed from α-LA from bovine milk. The amino acid at site 71 was Asn (N) in domestic yak milk, but Asp (D) in bovine and wild yak milk sequences. Yak ß-LG had 2 variants, ß-LG A (P02754) and ß-LG E (L8J1Z0). Both domestic yak and wild yak milk contained ß-LG E, but it was absent in bovine milk. The amino acid at site 158 of ß-Lg E was Gly (G) in yak but Glu (E) in bovine. The yak α-LA and ß-LG secondary structures were slightly different from those in bovine milk. The denaturation temperatures of yak α-LA and ß-LG were 52.1°C and 80.9°C, respectively. This study provides insights relevant to food functionality, food safety control, and the biological properties of yak milk products.
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Lactalbumina , Lactoglobulinas , Animais , Bovinos , Lactalbumina/genética , Lactoglobulinas/genética , Leite , Proteínas do Leite , Proteínas do Soro do LeiteRESUMO
Two types of ultra-broadband long wavelength infrared (LWIR) absorbers with small period and super thin thickness are designed. The absorption with high absorptivity and large bandwidth is achieved through combined propagating and localized surfaced plasmon resonances. We first design a three-layer absorber with a Ti-Ge-Ti configuration, the period of the structure is only 1.4 µm (nearly 1/8 of the center wavelength), the thickness of its dielectric is only 0.5 µm (1/22 of the center wavelength), and the average absorption is 87.9% under normal incident from 8µm to 14µm. Furthermore, the four-layer absorber with a Ti-Ge-Si3N4-Ti configuration is designed to obtain more average absorption increasing to 94.5% from 8 µm to 14µm under normal incident, the period of the structure increases to 1.6 µm and the total thickness of dielectric increases to 0.6µm. The proposed absorber is polarization-independent and possesses a good tolerance of incident angle. We calculate that the average absorption of the four-layer absorber for both TE- and TM-modes still exceeds 90% up to an incident angle of θ = 40° (90.7% for TE-mode, 91.9% for TM-mode), and exceed 80% up to an incident angle of θ = 60° (80.2% for TE-mode, 82.1% for TM-mode).
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A dual-band metamaterial absorber based on local surface plasmon resonance is designed, which is composed of a periodic arrangement of stacked nanodisk structures. The structure unit consists of two dielectric layers and three metal layers. Based on the finite difference time domain method, under the condition of vertically incident plane light, two absorption peaks in the mid-wave infrared and long-wave infrared (MWIR/LWIR) are obtained, and the absorption is greater than 98%. The absorber has good incident state tolerance characteristics. We can modulate the MWIR/LWIR absorption peaks by changing the radius of the stacked disk structure, and MWIR and LWIR dual-band broadband absorption can be achieved by integrating different size elements in the plane. The average absorption is 71% for MWIR with 1.1 µm bandwidth from 3.2 to 4.3 µm and 88% for LWIR with 3 µm bandwidth from 8.5 to 11.5 µm. At the same time, the structure also has effective refractive index (RI) sensitivity characteristics. In the RI range of 1.8-2, the maximum RI sensitivity of the LWIR and the MWIR is 1085 nm/refractive index unit (RIU) and 1472 nm/RIU, respectively.
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Enantioselective intramolecular dearomative Heck reactions have been developed by Pd-catalyzed cross-coupling of aryl halides or aryl triflates with the internal CâC bond of indoles, benzofurans, pyrroles, and furans. A variety of structurally unique spiroheterocycles and benzofused heterocycles having N/O-substituted quaternary carbon stereocenters, and exocyclic olefin moieties were afforded in moderate to excellent yields with good to excellent enantioselectivities, showing a broad scope of the present protocol. A series of new BINOL- and H8-BINOL-based phosphoramidite ligands were synthesized and proved to be efficient chiral ligands in the reactions of C2-tethered substrates to form spiroheterocycles. ( S)-SEGPHOS turned out to be a good ligand for the reaction delivering benzofused indolines and pyrrolines. Synthetic applications based on transformations of the exocyclic double bonds were realized without loss of enantiopurities, including hydrogenation, hydroborylation, and stereospecific ring-expanding rearrangement.
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The metastatic potential of malignant tumor has been shown to be correlated with the increased expression of tri- and tetra-antennary ß1,6-N-acetylglucosamine (ß1,6-GlcNAc) N-glycans. In this study, We found that GnT-V expression was negatively correlated with receptor protein tyrosine phosphatase type µ(RPTPµ) in human glioma tissues. To study whether RPTPµ is a novel substance of GnT-V which further affect RPTPµ's downstream dephosphorylation function, we preform lentiviral infection with GnT-V gene to construct stably transfected GnT-V glial cell lines. We found RPTPµ undergone severer cleavage in GnT-V transfected glioma cells compare to Mock cells. RPTPµ intracellular domain fragments increased while ß1,6-GlcNAc-branched N-glycans increased, in consistent with the decrease of RPTPµ's catalytic activity. The results showed that abnormal glycosylation could decrease the phosphorylation activity of PTP µ, and affect PLCγ-PKC pathways. Both protease inhibitor Furin and N-glycan biosynthesis inhibitor swainsonine could decrease cell mobility in GnT-V-U87 transfectants and other glioma cell lines. All results above suggest increased post-translational modification of RPTPµ N-glycans by GnT-V attenuates its tyrosine phosphatase activity and promotes glioma cell migration through PLCγ-PKC pathways, and that the ß1,6-GlcNAc-branched N-glycans of RPTPµ play a crucial role in glioma invasivity.
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Glioma/enzimologia , N-Acetilglucosaminiltransferases/metabolismo , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/metabolismo , beta-Glucanas/metabolismo , Movimento Celular , Adesões Focais , Glioma/fisiopatologia , Glicosilação , Humanos , Fosfolipase C gama/metabolismo , Proteína Quinase C/metabolismo , Transdução de SinaisRESUMO
Cadherin is crucial for cell-cell adhesion and N-glycosylation of N-cadherin has been implicated in the process of mammary, renal, and ovarian carcinogenesis. However, whether N-glycosylation of N-cadherin plays a role in glioma remains unknown. Previous studies had indicated that N-glycosylation could occur at three asparagine residues of N-cadherin. By generating and over-expressing N-glycosylation-deficient N-cadherin mutants in the human glioma cell lines SHG66 and U87, we found that mutation of N402 but not of the other potentially N-glycosylated residues destabilized N-cadherin and led to its ubiquitylation and subsequent proteasomal degradation. Furthermore, destabilized N-cadherin inhibited cadherin-mediated cell-cell adhesion and promoted cell migration. Our findings reveal that N-glycosylation controls N-cadherin stability and plays a role in glioma migration. J. Cell. Biochem. 118: 1423-1431, 2017. © 2016 Wiley Periodicals, Inc.
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Antígenos CD/química , Antígenos CD/metabolismo , Asparagina/química , Caderinas/química , Caderinas/metabolismo , Glioma/metabolismo , Antígenos CD/genética , Asparagina/genética , Caderinas/genética , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Glioma/genética , Glicosilação , Humanos , Mutação , N-Acetilglucosaminiltransferases/metabolismo , Estabilidade ProteicaRESUMO
Receptor-like protein tyrosine phosphatase alpha (RPTPα or PTPα), a type I transmembrane glycoprotein with complex N-glycans, executes multifunction roles on cell behaviors. However, its effect on tumorigenesis and metastasis remains controversial. In this study, PTPα is identified as a novel substrate of N-Acetylglucosaminyltransferase V (GnT-V). Immunofluorescence results showed that addition of ß1,6 GlcNAc branches on PTPα enhanced PTPα's cytomembrane assemble in GnT-V-MCF-7 compared with Mock-MCF-7 (MCF7 cells transfected with the vector pcDNA3). Then we found the alleviating degradation of PTPα was observed in GnT-V-MCF-7 while PTPα in Mock-MCF-7 was prone to quick degradation. Increased cell-surface retention subsequently enhanced PTPα's catalytic activity on the dephosphorylation of Src kinase at Tyr529 and promoted focal adhesion formation and mature. Therefore, our findings could provide an insight into the molecular mechanism of how GnT-V promoted cell migration, suggesting that PTPα could be one of factors regulating promote migration of breast cancer cell.