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1.
J Am Chem Soc ; 146(25): 17428-17437, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38866732

RESUMEN

Synthetic challenges toward anomalous structures and electronic states often involve handling problems such as insolubility in common organic solvents and oxidative degradation under aerobic conditions. We designed benzo-annulated aza[n]helicenes, which benefit from both the suppressed elevation of highest occupied molecular orbital (HOMO) energies and high solubility due to hydrogen bonding with solvent molecules to overcome these challenges. This strategy enabled the synthesis of six new aza[n]helicenes ([n]AHs) of different lengths (n = 9-19) from acyclic precursors via one-pot intramolecular oxidative fusion reactions. The structures of all of the synthesized aza[n]helicenes were determined by X-ray diffraction (XRD) analysis, and their electrochemical potentials were measured by cyclic voltammetry. Among the synthesized aza[n]helicenes, [17]AH and [19]AH are the first heterohelicenes with a triple-layered helix. The noncovalent interaction (NCI) plots confirm the existence of an effective π-π interaction between the layers. The absorption and fluorescence spectra red-shifted as the helical lengths increased, without any distinct saturation points. The optical resolutions of N-butylated [9]AH, [11]AH, [13]AH, and [15]AH were accomplished, and their circular dichroism (CD) and circularly polarized luminescence (CPL) were measured. Thus, the structural, (chir)optical, and electrochemical properties of the aza[n]helicenes were comprehensively analyzed.

2.
PLoS Genet ; 17(8): e1009727, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34407079

RESUMEN

Vps13 family proteins are proposed to function in bulk lipid transfer between membranes, but little is known about their regulation. During sporulation of Saccharomyces cerevisiae, Vps13 localizes to the prospore membrane (PSM) via the Spo71-Spo73 adaptor complex. We previously reported that loss of any of these proteins causes PSM extension and subsequent sporulation defects, yet their precise function remains unclear. Here, we performed a genetic screen and identified genes coding for a fragment of phosphatidylinositol (PI) 4-kinase catalytic subunit and PI 4-kinase noncatalytic subunit as multicopy suppressors of spo73Δ. Further genetic and cytological analyses revealed that lowering PI4P levels in the PSM rescues the spo73Δ defects. Furthermore, overexpression of VPS13 and lowering PI4P levels synergistically rescued the defect of a spo71Δ spo73Δ double mutant, suggesting that PI4P might regulate Vps13 function. In addition, we show that an N-terminal fragment of Vps13 has affinity for the endoplasmic reticulum (ER), and ER-plasma membrane (PM) tethers localize along the PSM in a manner dependent on Vps13 and the adaptor complex. These observations suggest that Vps13 and the adaptor complex recruit ER-PM tethers to ER-PSM contact sites. Our analysis revealed that involvement of a phosphoinositide, PI4P, in regulation of Vps13, and also suggest that distinct contact site proteins function cooperatively to promote de novo membrane formation.


Asunto(s)
1-Fosfatidilinositol 4-Quinasa/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Esporas Fúngicas/genética , 1-Fosfatidilinositol 4-Quinasa/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Portadoras/genética , Membrana Celular/metabolismo , Retículo Endoplásmico/metabolismo , Membranas/metabolismo , Membranas Mitocondriales/metabolismo , Transporte de Proteínas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
3.
Angew Chem Int Ed Engl ; : e202408478, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38829748

RESUMEN

Singly-linked aromatic [22]smaragdyrin BF2 complex dimer was synthesized by the reductive coupling of 16-brominated [22]smaragdyrin BF2 complex, which was oxidized to a stable diradical with PbO2. As the first example of fused smaragdyrin dimer, a fused [22]smaragdyrin BF2 complex dimer was synthesized by the oxidation of a CuCl-BF2 complex dimer with FeCl3 and subsequent reduction with NaBH4. After removal of the BF2 group, the singly-linked and fused aromatic dimers were oxidized to the corresponding antiaromatic [20]smaragdyrin free base dimers. The first oxidation and reduction potentials of these dimers are split depending upon the intramolecular electronic interactions, which are larger for the fused dimers. Despite the large electronic interactions, the aromatic and antiaromatic characters are well preserved in the fused dimers.

4.
Angew Chem Int Ed Engl ; 63(23): e202405059, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38563771

RESUMEN

We present herein the synthesis of novel pseudo-metalla-carbaporphyrinoid species (1M: M=Pd and Pt) achieved through the inner coordination of palladium(II) and platinum(II) with an acyclic N-confused tetrapyrrin analogue. Despite their tetrapyrrole frameworks being small, akin to well-known porphyrins, these species exhibit an unusually narrow HOMO-LUMO gap, resulting in an unprecedentedly low-energy absorption in the second near-infrared (NIR-II) region. Density functional theory (DFT) calculations revealed unique dπ-pπ-conjugated electronic structures involving the metal dπ-ligand pπ hybridized molecular orbitals of 1M. Magnetic circular dichroism (MCD) spectroscopy confirmed distinct electronic structures. Remarkably, the complexes feature an open-metal coordination site in the peripheral NN dipyrrin site, forming hetero-metal complexes (1Pd-BF2 and 1Pt-BF2) through boron difluoride complexation. The resulting hetero metalla-carbaporphyrinoid species displayed further redshifted NIR-II absorption, highly efficient photothermal conversion efficiencies (η; 62-65 %), and exceptional photostability. Despite the challenges associated with the theoretical and experimental assessment of dπ-pπ-conjugated metalla-aromaticity in relatively larger (more than 18π electrons) polycyclic ring systems, these organometallic planar tetrapyrrole systems could serve as potential molecular platforms for aromaticity-relevant NIR-II dyes.

5.
Cytokine ; 169: 156280, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37356260

RESUMEN

OBJECTIVES: To investigate the clinical significance of serum cytokine profiles for differentiating between Kawasaki disease (KD) and its mimickers. METHODS: Patients with KD, including complete KD, KD shock syndrome (KDSS), and KD with macrophage activation syndrome (KD-MAS), and its mimickers, including multisystem inflammatory syndrome in children, toxic shock syndrome, and Yersinia pseudotuberculosis infection, were enrolled. Serum levels of interleukin (IL)-6, soluble tumor necrosis factor receptor type II (sTNF-RII), IL-10, IL-18, and chemokine (C-X-C motif) ligand 9 (CXCL9) were measured using enzyme-linked immunosorbent assay and compared them with clinical manifestations. RESULTS: Serum IL-6, sTNF-RII, and IL-10 levels were significantly elevated in patients with KDSS. Serum IL-18 levels were substantially elevated in patients with KD-MAS. Patients with KD-MAS and KD mimickers had significantly elevated serum CXCL9 levels compared with those with complete KD. Area under the receiver operating characteristic curve analysis showed that serum IL-6 was the most useful for differentiating KDSS from the others, IL-18 and CXCL9 for KD-MAS from complete KD, and CXCL9 for KD mimickers from complete KD and KD-MAS. CONCLUSION: Serum cytokine profiles may be useful for differentiating between KD and its mimickers.


Asunto(s)
Citocinas , Síndrome Mucocutáneo Linfonodular , Choque Séptico , Síndrome de Respuesta Inflamatoria Sistémica , Infecciones por Yersinia pseudotuberculosis , Síndrome Mucocutáneo Linfonodular/sangre , Síndrome Mucocutáneo Linfonodular/diagnóstico , Citocinas/sangre , Humanos , Interleucina-6/sangre , Quimiocina CXCL9/sangre , Síndrome de Activación Macrofágica/sangre , Síndrome de Activación Macrofágica/diagnóstico , Masculino , Femenino , Niño , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Diagnóstico Diferencial , Choque Séptico/sangre , Choque Séptico/diagnóstico , Infecciones por Yersinia pseudotuberculosis/sangre , Infecciones por Yersinia pseudotuberculosis/diagnóstico , Síndrome de Respuesta Inflamatoria Sistémica/sangre , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico
6.
Chemistry ; 29(14): e202203517, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36479740

RESUMEN

m-Benziporphyrin(1.1.0.0) and m-pyreniporphyrin(1.1.0.0) were prepared as ring-contracted carbaporphyrins. While m-Benziporphyrin(1.1.0.0) was unstable, m-pyreniporphyrin(1.1.0.0) was fairly stable. Both of their PdII complexes showed distorted coordination structures with extremely short Pd-C bonds. As compared with the reported m-benziporphyrin PdII complexes, these PdII complexes showed considerably small HOMO-LUMO gaps, despite their smaller molecular size. PdII metalation of the m-pyreniporphyrin(1.1.0.0) dimer gave the corresponding PdII complex, which showed similar distorted coordination and a smaller HOMO-LUMO gap. Finally, PdII metalation of a pyrene-sharing formal p-benziporphyrin(1.1.1.1) dimer gave a nonaromatic PdII dimer, which rearranged to an aromatic PdII complex upon treatment with alumina.

7.
Chemistry ; 29(11): e202203484, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36422469

RESUMEN

meso-Trimesityl-substituted [20]smaragdyrin freebase was synthesized by p-toluenesulfonic acid catalyzed reaction of 5-mesityldipyrromethane and 2,14-dibromodipyrrin in an improved yield of 63 %. Unexpectedly, treatment of the [20]smaragdyrin freebase with BF3 ⋅ OEt2 and triethylamine (TEA) gave a stable radical species, in which the BF2 unit is coordinated at the tripyrrin site, probably by ready release of a hydrogen atom of a [22]smaragdyrin BF2 complex. Similar treatment of [22]smaragdyrin free base produced another [22]smaragdyrin BF2 complex, in which the BF2 unit is coordinated at the dipyrrin site. The tripyrrin site coordinated neutral radical was oxidized with AgSbF6 to give a stable antiaromatic cation; this was reduced with NaBH4 to its 22π congener, which was easily oxidized back to the neutral radical in the air and rearranged to thermodynamically stable dipyrrin site coordinated [22]smaragdyrin BF2 complex upon treatment with BF3 ⋅ OEt2 and TEA. Further, the dipyrrin site coordinated [22]smaragdyrin BF2 complex was similarly oxidized to a stable neutral radical and a stable cation in a stepwise manner. This work demonstrates a rare ability of smaragdyrin BF2 complexes to exist in multiple redox states, particularly forming a stable neutral radical by facile release of a hydrogen atom.

8.
Org Biomol Chem ; 21(6): 1158-1162, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36633268

RESUMEN

Dissymmetrical α,α'-disubstituted tripyrrins have been prepared using a modified synthetic protocol. Tripyrrin 2a bearing 3,5-bis(trifluoromethyl)phenyl and 4-methoxyphenyl moieties showed an anti-type dimer arrangement in the solid state. In contrast, syn-type dimers were observed for tripyrrin 2b bearing 3,5-bis(trifluoromethyl)phenyl and 3,5-di-t-butylphenyl moieties. In addition, proton-exchange NH tautomerization was observed in 2b.

9.
Dig Surg ; 40(1-2): 84-89, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36848877

RESUMEN

We report a case of pathologic complete response after successful treatment for advanced hepatocellular carcinoma (HCC) complicated with portal venous tumor thrombus with atezolizumab and bevacizumab followed by radical resection. The patient was a male in his 60s. During follow-up for chronic hepatitis B, abdominal ultrasonography revealed a huge tumor located in the right lobe of the liver with the portal vein thrombosed by the tumor. The tumor thrombus extended to the proximal side of the left branch of the portal vein. The patient's tumor marker levels were elevated (alpha-phetoprotein, 14,696 ng/mL; PIVKA-II, 2,141 mAU/mL). Liver biopsy revealed poorly differentiated HCC. The lesion was categorized as advanced stage according to the BCLC staging system. As systemic therapy, atezolizumab plus bevacizumab was administered. Imaging showed marked shrinkage of the tumor and portal venous thrombus with a remarkable decrease of tumor marker levels after 2 courses of chemotherapy. After 3 additional courses of chemotherapy, radical resection was considered possible. The patient underwent right hemihepatectomy and portal venous thrombectomy. A pathological examination revealed a complete response. In conclusion, we experienced a case in which advanced HCC was curatively treated with atezolizumab plus bevacizumab, which was administered as systemic therapy with a view to conversion surgery.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Trombosis , Trombosis de la Vena , Masculino , Humanos , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Bevacizumab/uso terapéutico , Trombosis de la Vena/etiología , Trombosis de la Vena/complicaciones , Trombosis/diagnóstico por imagen , Trombosis/tratamiento farmacológico , Trombosis/etiología , Biomarcadores de Tumor , Vena Porta/cirugía
10.
Angew Chem Int Ed Engl ; 62(28): e202302662, 2023 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-37163308

RESUMEN

Internally-bridged octaphyrin(1.1.1.1.1.1.1.1) underwent a rearrangement to meso-meso linked porphyrin dimer as a new metamorphosis. Extensive examination suggests that hydride-addition is a key step for the rearrangements to afford thermodynamically more stable porphyrin framework. Further, ß-tetrabromo[36]octaphyrin was transformed to meso-meso, ß-ß, ß-ß triply linked porphyrin dimer via a similar mechanism combined with Pd-mediated reductive homocoupling.

11.
Angew Chem Int Ed Engl ; 62(50): e202314968, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-37883214

RESUMEN

Oxidative fusion reaction of cyclic heteroaromatic pentads consisting of pyrrole and thiophene gave closed-heterohelicene monomers and dimers depending on the oxidation conditions. Specifically, oxidation with [bis(trifluoroacetoxy)iodo]benzene (PIFA) gave closed-[7]helicene dimers connected at the ß-position of one of the pyrrole units with remarkably elongated C-C bonds of about 1.60 Å. Although this bond was intact against thermal and physical activations, homolytic bond dissociation took place in DMSO upon irradiation with UV light to give the corresponding monomers. Thus, interconversion between the closed-helicene monomer and dimer was achieved. The optically pure dimer was photo-dissociated into the monomers associated with a turn-on of circularly polarized luminescence (CPL).

12.
Chemistry ; 28(20): e202200328, 2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35218265

RESUMEN

Directly meso-meso linked porphyrin-tetrabromo[36]octaphyrin-porphyrin hybrid trimer 10 was successfully synthesized via acid-catalyzed condensation reaction and subsequent oxidation. ZnII -metalation of 10 induced transannular meso-meso bond formation to give Möbius aromatic bis-ZnII octaphyrin 11, which was oxidized by DDQ/Sc(OTf)3 to provide fully conjugated porphyrin-[36]octaphyrin-porphyrin hybrid tape 12 as the first example of porphyrin tape exhibiting Möbius aromaticity. Hybrid tape 12 displays significantly red-shifted absorption and small electrochemical HOMO-LUMO gap, indicating the effective conjugation through the whole chromophores.

13.
Chemistry ; 28(68): e202202682, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36089560

RESUMEN

A meso-free ß-bromodecaphyrin has been constructed by [2+3+2+3] type acid-catalyzed cross-condensation and subsequent oxidation. Hydrodebromination of this tetrabromodecaphyrin with NaBH4 in the presence of TMEDA and palladium catalyst afforded ß-unsubstituted doubly meso-free [46]decaphyrin(1.1.1.1.1.1.1.1.1.1) as the first example of ß-unsubstituted meso-free regular expanded porphyrins with the number of pyrrole units larger than eight. It exhibits distinct aromaticity originating from its 46π-conjugated electronic circuit and flexible conformational change between non-twisted and doubly twisted forms depending on the solvent-polarity. Their distinct conformations have been analyzed by combined experimental and theoretical investigations.

14.
Helicobacter ; 27(4): e12908, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35661483

RESUMEN

BACKGROUND: Helicobacter bilis, an enterohepatic Helicobacter species, represents a carcinogenic risk factor for cholangiocytes owing to the prevalence of infections in patients with biliary tract cancer, cholecystitis, and pancreaticobiliary maljunction. However, the effect of H. bilis infection on cholangiocytes and the process and mechanism of carcinogenesis are not known. We aimed to determine the effects of H. bilis on cholangiocytes, focusing on inflammation and oxidative stress. MATERIALS AND METHODS: Helicobacter bilis and MMNK-1 cells were cocultured for 24 h and inflammatory cytokine secretion was evaluated. Furthermore, MMNK-1 cell proliferation, intracellular reactive oxidant species (ROS) production, and DNA damage caused by ROS were investigated. All factors were compared with and without H. bilis infection. RESULTS: Interleukin (IL)-6 and IL-8 secretion were significantly increased in MMNK-1 cocultures with H. bilis (IL-6, 24.3 ± 12.2 vs. 271.1 ± 286.4 pg/ml; IL-8, 167.6 ± 78.7 vs. 1085.1 ± 1047.1 pg/ml, p < .05). MMNK-1 proliferation was also significantly higher in H. bilis cocultures (1.05 ± 0.02 vs. 1.00-fold, respectively; p < .05). Coculturing enhanced the production of ROS in MMNK-1 cells depending on the cell concentration of H. bilis (1.0 vs. 1.17 ± 0.06, p < .05); however, DNA injury was not observed in cocultures with H. bilis (5.35 ± 0.87 vs. 6.08 ± 0.55 pg/µl, p = .06). CONCLUSIONS: Helicobacter bilis infection induced ROS production in and enhanced the proliferation of cholangiocytes.


Asunto(s)
Infecciones por Helicobacter , Helicobacter , Estrés Oxidativo , Proliferación Celular , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/genética , Humanos , Interleucina-6 , Interleucina-8 , Especies Reactivas de Oxígeno
15.
BMC Surg ; 22(1): 445, 2022 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-36581830

RESUMEN

BACKGROUND: Hospital-acquired disability (HAD) in patients who undergo living donor liver transplantation (LDLT) is expected to worsen physical functions due to inactivity during hospitalization. The aim of this study was to explore whether a decline in activities of daily living from hospital admission to discharge is associated with prognosis in LDLT patients, who once discharged from a hospital. METHODS: We retrospectively examined the relationship between HAD and prognosis in 135 patients who underwent LDLT from June 2008 to June 2018, and discharged from hospital once. HAD was defined as a decline of over 5 points in the Barthel Index as an activity of daily living assessment. Additionally, LDLT patients were classified into four groups: low or high skeletal muscle index (SMI) and HAD or non-HAD. Univariate and multivariate Cox proportional hazard models were used to evaluate the association between HAD and survival. RESULTS: HAD was identified in 47 LDLT patients (34.8%). The HAD group had a significantly higher all-cause mortality than the non-HAD group (log-rank: p < 0.001), and in the HAD/low SMI group, all-cause mortality was highest between the groups (log-rank: p < 0.001). In multivariable analysis, HAD was an independent risk factor for all-cause mortality (hazard ratio [HR]: 16.54; P < 0.001) and HAD/low SMI group (HR: 16.82; P = 0.002). CONCLUSION: HAD was identified as an independent risk factor for all-cause mortality suggesting that it could be a key component in determining prognosis after LDLT. Future larger-scale studies are needed to consider the overall new strategy of perioperative rehabilitation, including enhancement of preoperative physiotherapy programs to improve physical function.


Asunto(s)
Trasplante de Hígado , Humanos , Donadores Vivos , Alta del Paciente , Estudios Retrospectivos , Actividades Cotidianas , Cuidados Posteriores
16.
Sensors (Basel) ; 22(20)2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36298340

RESUMEN

Advances in micro-electro-mechanical systems technology have led to the emergence of compact attitude measurement sensor products that integrate acceleration, magnetometer, and gyroscope sensors on a single chip, making them important devices in the field of three-dimensional (3D) attitude measurement for unmanned aerial vehicles, smartphones, and other devices. Sensor fusion algorithms for posture measurement have become an indispensable technology in cutting-edge research, such as human posture measurement using wearable sensors, and stabilization problems in robot position and posture measurement. We have also developed wearable sensors and powered suits in our previous research. We needed a technology for the real-time measurement of a 3D human body motion. It is known that quaternions can be used to algebraically handle 3D rotations; however, sensor fusion algorithms for three sensors are presently complex. This is because these algorithms deal with the post-rotation attitude (pure quaternions) rather than rotation information (the rotor) to avoid a double covering problem involving the rotor. If we are dealing with rotation, it may be possible to make the algorithm simpler and faster by dealing directly with the rotor. In this study, to solve the double covering problem involving the rotor, we propose a stateful rotor and develop a technique for uniquely determining the time-varying states of the rotor. The proposed stateful rotor guarantees the continuity of the rotor parameters with respect to angular changes, and this paper confirms its effectiveness by simulating two rotations around an arbitrary axis. In addition, we verify experimentally that a fast sensor fusion method using stateful rotor can be used for attitude calculation. Experiments also confirm that the calculated results converge to the desired rotation angle for two spatial rotations around an arbitrary axis. Since the proposed stateful rotor extends and stabilizes the definition of the rotor, it is applicable to any algorithm that deals with time-varying quaternionic rotors. In this research, an algorithm based on a multiply-add operation is designed to reduce computational complexity as a high-speed calculation for embedded systems. This method is theoretically equivalent to other methods, while contributing to power saving and the cost reduction of products.


Asunto(s)
Algoritmos , Sistemas Microelectromecánicos , Humanos , Movimiento (Física) , Aceleración , Cuerpo Humano
17.
Int J Mol Sci ; 23(16)2022 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-36012469

RESUMEN

The epipharynx, located behind the nasal cavity, is responsible for upper respiratory tract immunity; however, it is also the site of frequent acute and chronic inflammation. Previous reports have suggested that chronic epipharyngitis is involved not only in local symptoms such as cough and postnasal drip, but also in systemic inflammatory diseases such as IgA nephropathy and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and Long COVID. Epipharyngeal Abrasive Therapy (EAT), which is an effective treatment for chronic epipharyngitis in Japan, is reported to be effective for these intractable diseases. The sedation of chronic epipharyngitis by EAT induces suppression of the inflammatory cytokines and improves systemic symptoms, which is considered to be one of the mechanisms, but there is no report that has proved this hypothesis. The purpose of this study was to clarify the anti-inflammatory effect of EAT histologically. The study subjects were 8 patients who were not treated with EAT and 11 patients who were treated with EAT for chronic epipharyngitis for 1 month or more. For immunohistochemical assessment, the expression pattern of IL-6 mRNA, which plays a central role in the human cytokine network, was analyzed using in situ hybridization. The expression of IL-6 in the EAT-treated group was significantly lower than those in the EAT nontreated group (p = 0.0015). In addition, EAT suppressed the expression of tumor necrosis factor alpha (TNFα), a crucial proinflammatory cytokine. As a result, continuous EAT suppressed submucosal cell aggregation and reduced inflammatory cytokines. Thus, EAT may contribute to the improvement of systemic inflammatory diseases through the suppression of IL-6 expression.


Asunto(s)
Interleucina-6 , Faringitis , Citocinas/genética , Humanos , Interleucina-6/genética , Faringitis/terapia , ARN Mensajero/genética
18.
Molecules ; 27(10)2022 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-35630738

RESUMEN

The self-assembly of discrete cyanometallates has attracted significant interest due to the potential of these materials to undergo soft metallophilic interactions as well as their optical properties. Diblock copolypeptide amphiphiles have also been investigated concerning their capacity for self-assembly into morphologies such as nanostructures. The present work combined these two concepts by examining supramolecular hybrids comprising cyanometallates with diblock copolypeptide amphiphiles in aqueous solutions. Discrete cyanometallates such as [Au(CN)2]-, [Ag(CN)2]-, and [Pt(CN)4]2- dispersed at the molecular level in water cannot interact with each other at low concentrations. However, the results of this work demonstrate that the addition of diblock copolypeptide amphiphiles such as poly-(L-lysine)-block-(L-cysteine) (Lysm-b-Cysn) to solutions of these complexes induces the supramolecular assembly of the discrete cyanometallates, resulting in photoluminescence originating from multinuclear complexes with metal-metal interactions. Electron microscopy images confirmed the formation of nanostructures of several hundred nanometers in size that grew to form advanced nanoarchitectures, including those resembling the original nanostructures. This concept of combining diblock copolypeptide amphiphiles with discrete cyanometallates allows the design of flexible and functional supramolecular hybrid systems in water.


Asunto(s)
Nanoestructuras , Agua , Microscopía Electrónica , Nanoestructuras/química
19.
Angew Chem Int Ed Engl ; 61(1): e202112589, 2022 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-34738305

RESUMEN

Peripherally π-extended corannulenes bearing quintuple azahelicene units, 10 and 11, were prepared and their dynamic behaviors were studied experimentally and theoretically. The fused corannulenes were synthesized from sym-pentabromocorannulene in three steps. X-Ray diffraction analysis for 10 displayed a conformer possessing a P(M) bowl chirality and a PPMPM (PMPMM) helical chirality, which was found to be the most stable conformer(s). Variable-temperature NMR measurements of 10 and 11 revealed that their structural isomers can be interconvertible in solution, depending on the steric congestion around the helical scaffolds. Automated search for conformers in the equilibrium and transition states by Artificial Force Induced Reaction (AFIR) method revealed their interconversion networks, including bowl-inversion and helical-inversion. This analysis indicated that the co-existing corannulene and azahelicene moieties influence the conformational dynamics, which leads to mitigation of the activation energy barriers for isomerization.

20.
Angew Chem Int Ed Engl ; 61(11): e202116789, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-34995398

RESUMEN

A pentabenzopentaaza[10]circulene has been synthesized as the largest fully conjugated hetero[n]circulene via a fold-in oxidative fusion reaction of an ortho-phenylene-bridged cyclic pyrrole pentamer. This circulene takes a saddle-distorted structure with bond lengths of the central ten-membered-ring in the range of 1.455-1.493 Å. Relatively broad absorption and fluorescence spectra were observed, which reflects its flexible structure, in accordance with the low-temperature NMR spectra and theoretical calculations. The energy barrier for saddle-to-saddle interconversion was estimated to be quite small (≈3 kcal mol-1 ).

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