Cancer incidence is rising, and the efficacy of current available anticancer agents is limited by severe dose‐limiting toxicities and drug resistance problems. Nanoparticles are heralded as the next ...frontier in cancer treatment. Here, a pure physical method is used to efficiently fabricate very small silver particles even approaching the Ångstrom (Ång) dimension. Fructose is used as a dispersant and stabilizer to coat the Ång‐scale silver particles (AgÅPs). Functional and mechanistic studies demonstrate that fructose‐coated AgÅPs (F‐AgÅPs) can enter and accumulate in multiple cultured cancer cell lines to induce apoptotic death, whereas most normal cells are resistant to the efficacious dose of F‐AgÅPs; in vivo, intravenous administration of F‐AgÅPs potently inhibits the growth of pancreatic and lung cancer xenografts in nude mice, without inducing notable toxic effects on the healthy tissues. The results suggest the promising potential of F‐AgÅPs as a potent, safe, and broad‐spectrum agent for the cancer treatment.
Physical method‐fabricated fructose‐coated Ångstrom‐scale silver particles (F‐AgÅPs) have the ability to enter multiple cancer cells to induce apoptosis. Intravenous injection of F‐AgÅPs potently inhibits the growth of cancer xenograft models, without inducing notable toxic effects on healthy tissues. These results suggest that F‐AgÅPs have a great potential to be used as a potent, safe, and broad‐spectrum agent for cancer treatment.
The triad types of molecules with various combinations of electron donors (D) and acceptors (A) have been widely explored in optoelectronics. However, their photophysical and photochemical ...properties, which are frequently unconventional, are relatively unexplored. In this study, a donor–donor–acceptor (D–D–A)-type triad, CTPS, consisting of the donor moiety of triphenylamine (D1) and the acceptor moiety of dibenzothiophene sulfone (A) bridging through the second donor carbazole (D2) into a U-shape configuration, was synthesized. CTPS exhibited dual emission bands, both of which reveal solvent-polarity-dependent solvatochromism and unusual excitation-wavelength-dependent ratiometric emission. Comprehensive studies clarified that two emissions originate from two different D–A charge-transfer (CT) states. The lower-energy CT(S) state possesses D1 → A through-space CT nature with optically forbidden transition, whereas the higher-lying CT(B) state is associated with optically allowed D2 → A CT through the π-conjugation transition. Upon S0 → CT(B) excitation, the charge transfer creates D2δ+Aδ− dipolar changes and Aδ−–D1 repulsion, leading to structural relaxation of the CT(B) state that competes with fast CT(B) → CT(S) internal conversion. Therefore, despite the fact that they originate from the same Franck–Condon excited state, both energy-stabilized CT(B) and CT(S) states are populated through two independent channels. The stabilized CT(B) and CT(S) states possess different optimized geometries and do not interconvert during their lifespans, rendering different population decay time constants. The slim highest occupied molecular orbital/lowest unoccupied molecular orbital overlapped D1–A CT(S) state exhibits thermally activated delayed fluorescence (TADF), the character of which was further exploited as a host in organic light-emitting diode. The results gain new insights into the properties of the bending-type D–D–A TADF triads. CTPS should not be a unique case. Bizarre photophysical behavior encountered in molecules comprising multiple D and A groups may involve the interplay among various local CT states, which might have been overlooked.
Shrimp white spot disease (WSD), which is caused by white spot syndrome virus (WSSV), is one of the world's most serious shrimp diseases. Our objective in this study was to use an immunomagnetic ...reduction (IMR) assay to develop a highly sensitive, automatic WSSV detection platform targeted against ICP11 (the most highly expressed WSSV protein). After characterizing the magnetic reagents (Fe3O4 magnetic nanoparticles coated with anti ICP11), the detection limit for ICP11 protein using IMR was approximately 2 x 10(-3) ng/ml, and the linear dynamic range of the assay was 0.1~1 x 10(6) ng/ml. In assays of ICP11 protein in pleopod protein lysates from healthy and WSSV-infected shrimp, IMR signals were successfully detected from shrimp with low WSSV genome copy numbers. We concluded that this IMR assay targeting ICP11 has potential for detecting the WSSV.
The friction generated between a finger and an object forms the mechanical stimuli behind fine touch perception. To control friction, and therefore tactile perception, current haptic devices ...typically rely on physical features like bumps or pins, but chemical and microscale morphology of surfaces could be harnessed to recreate a wider variety of tactile sensations. Here, we sought to develop a new way to create tactile sensations by relying on differences in microstructure as quantified by the degree of crystallinity in polymer films. To isolate crystallinity, we used polystyrene films with the same chemical formula and number averaged molecular weights, but which differed in tacticity and annealing conditions. These films were also sufficiently thin as to be rigid which minimized effects from bulk stiffness and had variations in roughness lower than detectable by humans. To connect crystallinity to human perception, we performed mechanical testing with a mock finger to form predictions about the degree of crystallinity necessary to result in successful discrimination by human subjects. Psychophysical testing verified that humans could discriminate surfaces which differed only in the degree of crystallinity. Although related, human performance was not strongly correlated with a straightforward difference in the degree of crystallinity. Rather, human performance was better explained by quantifying transitions in steady to unsteady sliding and the generation of slow frictional waves (
r
2
= 79.6%). Tuning fine touch with polymer crystallinity may lead to better engineering of existing haptic interfaces or lead to new classes of actuators based on changes in microstructure.
Humans can distinguish thin films of polystyrene which differed only in their degree of crystallinity.
Thioxanthone derivatives consisting of undecorated carbazole as an electron donor and thioxanthone (TXO) or 9H-thioxanthen-9-one-S,S-dioxide (SOXO) as an electron acceptor in a donor–acceptor (D–A) ...or donor–acceptor–donor (D–A–D) structure were developed as thermally activated delayed fluorescence emitters to fabricate highly efficient fluorescent organic light emitting diodes. Their emission color was successfully tuned from blue to yellow by changing the sulfur atom valence state of the thioxanthone unit to tune intramolecular charge transfer effect. Their thermal, electrochemical, photophysical, and electroluminescent properties, and theoretical calculations were systematically investigated to illustrate the molecular structure and property relationships. Maximum external quantum efficiency (EQE) of 13.6% with Commission Internationale de L’Eclairage coordinates of (0.37, 0.57) was achieved for green light emission CzSOXO consisting of SOXO and carbazole in a D–A structure. Blue light emission CzTXO and DCzTXO consisting of TXO and carbazole in a D–A and D–A–D structure could also give EQE values exceeding 11%. Their efficiency roll-off with increasing current density was simulated by adopting triplet–triplet annihilation model, indicating that the TXO derivatives suffer more severe efficiency roll-off because of their relatively long delayed fluorescence lifetime (τD).
The mechanical stimuli generated as a finger interrogates the physical and chemical features of an object form the basis of fine touch. Haptic devices, which are used to control touch, primarily ...focus on recreating physical features, but the chemical aspects of fine touch may be harnessed to create richer tactile interfaces and reveal fundamental aspects of tactile perception. To connect tactile perception with molecular structure, we systematically varied silane-derived monolayers deposited onto surfaces smoother than the limits of human perception. Through mechanical friction testing and cross-correlation analysis, we made predictions of which pairs of silanes might be distinguishable by humans. We predicted, and demonstrated, that humans can distinguish between two isosteric silanes which differ only by a single nitrogen-for-carbon substitution. The mechanism of tactile contrast originates from a difference in monolayer ordering, as quantified by the Hurst exponent, which was replicated in two alkylsilanes with a three-carbon difference in length. This approach may be generalizable to other materials and lead to new tactile sensations derived from materials chemistry.
We control the sense of touch through materials chemistry. To find tactile materials, we developed methods to screen materials and found that humans could distinguish surface monolayers which differed by a single atom substitution.
The commercially available polyelectrolyte complex poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is ubiquitous in organic and hybrid electronics. As such, it has often been ...used as a benchmark material for fundamental studies and the development of new electronic devices. Yet, most studies on PEDOT:PSS have focused on its electronic conductivity in dry environments, with less consideration given to its ion transport, coupled ionic-electronic transport, and charge storage properties in aqueous environments. These properties are essential for applications in bioelectronics (sensors, actuators), charge storage devices, and electrochromic displays. Importantly, past studies on mixed ionic-electronic transport in PEDOT:PSS neglected to consider how the molecular structure of PSS affects mixed ionic-electronic transport. Herein, we therefore investigated the effect of the molecular weight and size distribution of PSS on the electronic properties and morphology of PEDOT:PSS both in dry and aqueous environments, and overall performance in organic electrochemical transistors (OECTs). Using reversible addition-fragmentation chain transfer (RAFT) polymerization with two different chain transfer agents, six PSS samples with monomodal, narrow (
= 1.1) and broad (
= 1.7) size distributions and varying molecular weights were synthesized and used as matrices for PEDOT. We found that using higher molecular weight of PSS (
M
n
= 145 kg mol
−1
) and broad dispersity led to OECTs with the highest transconductance (up to 16 mS) and
μC
* values (∼140 F cm
−1
V
−1
s
−1
) in PEDOT:PSS, despite having a lower volumetric capacitance (
C
* = 35 ± 4 F cm
−3
). The differences were best explained by studying the microstructure of the films by atomic force microscopy (AFM). We found that heterogeneities in the PEDOT:PSS films (interconnected and large PEDOT- and PSS-rich domains) obtained from high molecular weight and high dispersity PSS led to higher charge mobility (
μ
OECT
∼ 4 cm
2
V
−1
s
−1
) and hence transconductance. These studies highlight the importance of considering molecular weight and size distribution in organic mixed ionic-electronic conductor, and could pave the way to designing high performance organic electronics for biological interfaces.
Controlling the dispersity of PSS allows to control the performance of PEDOT:PSS in organic electrochemical transistors (OECTs).
Organic mixed ionic-electronic conductors, such as poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), are essential materials for the fabrication of bioelectronic devices due to ...their unique ability to couple and transport ionic and electronic charges. The growing interest in bioelectronic devices has led to the development of organic electrochemical transistors (OECTs) that can operate in aqueous solutions and transduce ionic signals of biological origin into measurable electronic signals. A common challenge with OECTs is maintaining the stability and performance of the PEDOT:PSS films operating under aqueous conditions. Although the conventional approach of blending the PEDOT:PSS dispersions with a cross-linker such as (3-glycidyloxypropyl)trimethoxysilane (GOPS) helps to ensure strong adhesion of the films to device substrates, it also impacts the morphology and thus electrical properties of the PEDOT:PSS films, which leads to a significant reduction in the performance of OECTs. In this study, we instead functionalize only the surface of the device substrates with GOPS to introduce a silane monolayer before spin-coating the PEDOT:PSS dispersion on the substrate. In all cases, having a GOPS monolayer instead of a blend leads to increased electronic performance metrics, such as three times higher electronic conductivity, volumetric capacitance, and mobility-capacitance product μC* value in OECT devices, ultimately leading to a record value of 406 ± 39 F cm-1 V-1 s-1 for amorphous PEDOT:PSS. This increased performance does not come at the expense of operational stability, as both the blend and surface functionalization show similar performance when subjected to pulsed gate bias stress, long-term electrochemical cycling tests, and aging over 150 days. Overall, this study establishes a novel approach to using GOPS as a surface monolayer instead of a blended cross-linker, for achieving high-performance organic mixed ionic-electronic conductors that are stable in water for bioelectronics.
In this study, we used a systems biology approach to investigate changes in the proteome and metabolome of shrimp hemocytes infected by the invertebrate virus WSSV (white spot syndrome virus) at the ...viral genome replication stage (12 hpi) and the late stage (24 hpi). At 12 hpi, but not at 24 hpi, there was significant up-regulation of the markers of several metabolic pathways associated with the vertebrate Warburg effect (or aerobic glycolysis), including glycolysis, the pentose phosphate pathway, nucleotide biosynthesis, glutaminolysis and amino acid biosynthesis. We show that the PI3K-Akt-mTOR pathway was of central importance in triggering this WSSV-induced Warburg effect. Although dsRNA silencing of the mTORC1 activator Rheb had only a relatively minor impact on WSSV replication, in vivo chemical inhibition of Akt, mTORC1 and mTORC2 suppressed the WSSV-induced Warburg effect and reduced both WSSV gene expression and viral genome replication. When the Warburg effect was suppressed by pretreatment with the mTOR inhibitor Torin 1, even the subsequent up-regulation of the TCA cycle was insufficient to satisfy the virus's requirements for energy and macromolecular precursors. The WSSV-induced Warburg effect therefore appears to be essential for successful viral replication.
Transcatheter arterial chemoembolization (TACE) is a widely adopted treatment for advanced stage hepatocellular carcinoma (HCC). Nevertheless, several complications may occur, such as hepatic artery ...injury, nontarget embolization, pulmonary embolism, hepatic abscess, biloma, biliary strictures, and hepatic failure. However, bronchobiliary fistula is rarely mentioned before.
A 65-year-old man with HCC underwent the TACE procedure, and then he encountered fever, dyspnea, abdominal pain, and abundant yellowish purulent bronchorrhea.
Bronchobiliary fistula was diagnosed based on the computed tomography (CT) scan of his chest, which revealed the right lower lobe of his lung was connected to a hepatic cystic lesion.
Percutaneous transhepatic cystic drainage was performed, and we obtained yellowish bile, showing the same characteristics as the patient's bronchorrhea.
We kept drainage of his biloma and provided supportive care as the patient wished. Unfortunately, the patient passed away due to progressive right lower lobe pneumonia 2 weeks later.
This case exhibits a typical CT scan image that was helpful for the diagnosis of post-TACE bronchobiliary fistula. Post-TACE bronchobiliary fistula formation hypothesis includes biliary tree injuries with subsequent biloma formation and diaphragmatic injuries. Moreover, the treatment of bronchobiliary fistula should be prompt to cease pneumonia progression. Therefore, we introduce this rare complication of post-TACE bronchobiliary fistula in hopes that future clinicians will keep earlier intervention in mind.
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