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Monitoring electrical activity across multiple planes in 3D cell cultures and organoids is imperative to comprehensively understand their functional connections and behavior. However, traditional planar microelectrode arrays (MEAs) are intended for surface recordings and are inadequate in addressing this aspect. The limitations, such as longer production times and limited adaptability imposed by standard clean‐room techniques, constrain the design possibilities for 3D electrode arrays and potentially hinder effective cell‐electrode coupling. To tackle this challenge, a novel approach is presented that leverages rapid prototyping processes and additive manufacturing in combination with wet etching and electrodeposition to enhance electrode fabrication and performance. The laser‐patterned MEAs on glass, polyimide (PI) foil, or polyethylene terephthalate (PET) foil substrates incorporate high‐aspect ratio (up to 44:1) ink‐jet printed 3D electrode structures with heights up to 1 mm at a pitch of 200 µm, enabling precise recording within cell tissues. The specific shapes of the electrode tips and customizable 3D structures provide great flexibility in electrode placement. The versatility of the 3D MEAs is demonstrated by recording the electrophysiological activity of cortical organoids in situ, paving the way for investigating neural activity under regular or various pathologically altered conditions in vitro in a high throughput manner. [ABSTRACT FROM AUTHOR]

Secondary amines, due to their reactivity, can transform protein templates into catalytically active entities, accelerating the development of artificial enzymes. However, existing methods, predominantly reliant on modified ligands or N‐terminal prolines, impose significant limitations on template selection. In this study, genetic code expansion was used to break this boundary, enabling secondary amines to be incorporated into alternative proteins and positions of choice. Pyrrolysine analogues carrying different secondary amines could be incorporated into superfolder green fluorescent protein (sfGFP), multidrug‐binding LmrR and nucleotide‐binding dihydrofolate reductase (DHFR). Notably, the analogue containing a D‐proline moiety demonstrated both proteolytic stability and catalytic activity, conferring LmrR and DHFR with the desired transfer hydrogenation activity. While the LmrR variants were confined to the biomimetic 1‐benzyl‐1,4‐dihydronicotinamide (BNAH) as the hydride source, the optimal DHFR variant favorably used the pro‐R hydride from NADPH for stereoselective reactions (e.r. up to 92 : 8), highlighting that a switch of protein template could broaden the nucleophile option for catalysis. Owing to the cofactor compatibility, the DHFR‐based secondary amine catalysis could be integrated into an enzymatic recycling scheme. This established method shows substantial potential in enzyme design, applicable from studies on enzyme evolution to the development of new biocatalysts. [ABSTRACT FROM AUTHOR]

Scholarship on girlhood—especially for girls of Color—is often relegated to studying risk and emphasizing individual deficits over humanizing girls and centering their voices. This approach to generating scholarship renders oppressive systems and processes invisible from inquiry and unaddressed by practice, with particularly insidious consequences for youth in the legal system. Critical youth participatory action research (YPAR) is acknowledged as an antidote to these conceptualizations because it resists deficit‐oriented narratives circling systems‐impacted youth by inviting them to the knowledge‐generating table. In this paper, we present an empirical analysis of the promises and perils that emerged as we conducted a year‐long critical YPAR project alongside five system‐impacted girls of Color. Our thematic analysis of process notes (30 meetings, 120 h) documents the stories posited by girls, in a democratized space, about the injustices of interconnected institutions, and unearths a complicated tension for both youth and adult coresearchers around the promises and perils of engaging in YPAR within the academy. These findings underscore the importance of using intersectional, collaborative research to challenge perceptions around how we legitimize knowledge. We describe lessons learned in conducting YPAR in academic settings and highlight recommendations to grow youth–adult partnerships within oppressive systems to share power. Highlights: Critical YPAR is heralded as a liberatory epistemology for social justice committed research. We conducted critical YPAR with system‐impacted girls of Color. We synthesize the promises and perils of critical YPAR in a research‐intensive university setting. We name the limits inherent in imperial logics and structures between academia and legal systems. Recommendations focus on structural changes at the nexus of academia and other systems. [ABSTRACT FROM AUTHOR]

The results of in vivo immersion optical clearing of human skin under the action of two different optical clearing agents (OCAs), such as an aqueous sucrose solution and a radiographic contrast agent Omnipaque™ 300 (iohexol), were obtained with the use of optical coherence tomography (OCT) method. The rate of reduction of light scattering coefficient, obtained through an averaged A‐scan of the OCT image in the region of dermis within the depths from 350 to 700 μm, were determined to evaluate the efficiency of optical clearing (EOC). The correlations between the EOC and the energy of intermolecular interaction of OCAs with a fragment of collagen peptide have been established as a result of molecular modeling by quantum chemistry methods HF/STO3G/DFT/B3LYP/6—311G(d) of a number of OCAs (glycerol, iohexol, sucrose, ribose, fructose, glucose) with mimetic peptide of collagen (GPH)3. [ABSTRACT FROM AUTHOR]

We report here a series of original ligand‐supported trigonal planar Au@Ag3 clusters exhibiting bright solid‐state phosphorescence in violet to deep‐blue range (λmax=410–442 nm) with remarkably short decay times (0.36–1.36 μs) and up to 96 % emission quantum yield at 298 K. [ABSTRACT FROM AUTHOR]

The ability of 1‐hydroxy‐1H‐imidazoles to exist in the form of two prototropic tautomers, the N‐hydroxy and the N‐oxide forms, can be utilized in the design of new types of ESIPT‐fluorophores (ESIPT=excited state intramolecular proton transfer). Here we report the first example of 1‐hydroxy‐1H‐imidazole‐based ESIPT‐fluorophores, 1‐hydroxy‐5‐methyl‐2,4‐di(pyridin‐2‐yl)‐1H‐imidazole (HL), featuring a short intramolecular hydrogen bond O−H⋅⋅⋅N (O⋅⋅⋅N 2.56 Å) as a pre‐requisite for ESIPT. The emission of HL originates from the anti‐Kasha S2→S0 fluorescence in the N‐oxide form as a result of a large S2–S1 energy gap slowing down the S2→S1 internal conversion. Due to an energy barrier between the N‐hydroxy and N‐oxide forms in the ground state, the HL molecules can be trapped and photoexcited in the N‐oxide form leading to the Stokes shift of ca. 60 nm which is the smallest among known ESIPT‐fluorophores. [ABSTRACT FROM AUTHOR]

N‐reacetylated oligochitosan (RA‐oligoCHI) with molecular weight ≤ 12 kDa and a random‐type distribution of acetyl groups can form soluble RA‐CHI/SDS (SDS; sodium dodecyl sulfate) complexes and transparent solutions both in acidic, where RA‐oligoCHI is soluble, and alkaline aqueous media, where RA‐oligoCHI is soluble too, at SDS concentration above its critical micellar concentration. AN antibacterial activity test shows that RA‐CHIs preserve a high bacteriostatic activity toward S. aureus and E. coli in the presence of SDS both in acidic and alkaline aqueous solutions. The discovered compatibility and preservation of antibacterial activity can make promising the application of RA‐CHIs as artificial biocides for the preparation of microbiologically stable pharmaceutical hydrocolloids and cosmetic compositions containing strong anionic surfactants designed for topical applications. [ABSTRACT FROM AUTHOR]

The first example of a triply bridging (μ3‐P) phosphine ligand has been discovered in the crown‐shaped [Cu3(μ2‐Hal)3L] (Hal=Cl, Br, or I) complexes supported by tris[2‐(2‐pyridyl)ethyl]phosphine (L). Theoretical analysis completely confirms the observed μ3‐P‐bridging pattern, revealing the interaction of the same lone pair of phosphorus with three valence 4s‐orbitals of Cu atoms. The presented complexes exhibit outstanding blue phosphorescence (λem=442–465 nm) with the quantum efficiency reaching 100 %. The complex [Cu3(μ2‐I)3L] also exhibits remarkable thermo‐ and mechanochromic luminescence resulting in a sharp change in the emission colour upon external stimuli. These findings essentially contribute to coordination chemistry of the pnictine ligands. [ABSTRACT FROM AUTHOR]

Scholarship identifies critical consciousness as a key developmental asset in promoting the well‐being of adolescents experiencing multiple socio‐structural axes of oppression. Girls of color at acute risk for legal system involvement or re‐involvement are absent from this literature. They are a critical population in which to examine this construct given their experiences of oppression and the myriad benefits of critical consciousness. The current study addresses this gap by examining traumatic incidents and experiences of racism and sexism as correlates of critical reflection and action among a sample of girls (N = 220; Mean age = 14.5 years; SD = 1.3 years). Using path analysis and multigroup modeling, we examine direct associations between these three manifestations of structural oppression and critical consciousness and explore the interplay of traumatic incidents, and racism and sexism in girls' critical consciousness development. Findings suggest that experiences of sexism and racism, uniquely and positively predict critical action, but not critical reflection. Surprisingly, girls' experiences of traumatic incidents do not predict reflection or action. Finally, multigroup analyses show no evidence that these associations vary by the interplay of traumatic incidents, racism, and sexism. Implications for community psychology values and juvenile legal system practice and policy are discussed. Highlights: Experiences of sexism and racism uniquely predict critical action but not critical reflection.Traumatic incidents are not associated with critical reflection or critical action.System‐involved girls engage in multiple forms of critical action.Analyses show associations do not vary by the interplay of traumatic incidents, racism and sexism. [ABSTRACT FROM AUTHOR]

The monitoring of K+ in saliva, blood, urine, or sweat represents a future powerful alternative diagnostic tool to prevent various diseases. However, several K+ sensors are unable to meet the requirements for the development of point‐of‐care (POC) sensors. To tackle this grand‐challenge, the fabrication of chemiresistors (CRs) based on 3D networks of Au nanoparticles covalently bridged by ad‐hoc supramolecular receptors for K+, namely dithiomethylene dibenzo‐18‐crown‐6 ether is reported here. A multi‐technique characterization allows optimizing a new protocol for fabricating high‐performing CRs for real‐time monitoring of K+ in complex aqueous environments. The sensor shows exceptional figures of merit: i) linear sensitivity in the 10–3 to 10–6m concentration range; ii) high selectivity to K+ in presence of interfering cations (Na+, Ca2+, and Mg2+); iii) high shelf‐life stability (>45 days); iv) reversibility of K+ binding and release; v) successful device integration into microfluidic systems for real‐time monitoring; vi) fast response and recovery times (<18 s), and v) K+ detection in artificial saliva. All these characteristics make the supramolecular CRs a potential tool for future applications as POC devices, especially for health monitoring where the determination of K+ in saliva is pivotal for the early diagnosis of diseases. [ABSTRACT FROM AUTHOR]

Spectroscopic and photovoltaic properties of composites of purified and subsequently fluorinated single‐walled carbon nanotubes (F‐SWCNTs) with conjugated polymer poly(3‐hexylthiophene) (P3HT) are tested. Adding cyclohexanone into o‐dichlorobenzene solution of P3HT and F‐SWCNTs significantly affects the composite morphology and promotes P3HT/F‐SWCNT nanofilament formation, as evidenced from atomic force microscopy (AFM) images of spin‐coated composite films. Also, nanofilament formation enhances quenching of P3HT photoluminescence by F‐SWCNTs. The performance of P3HT‐based organic photovoltaics (OPV) devices with separated semiconducting SWCNTs and F‐SWCNTs as the acceptor component of the active layer is comparable. Light‐induced electron paramagnetic resonance (EPR) signal intensity in P3HT/F‐SWCNT composite films and frozen solutions grows with increase in F‐SWCNT content, which is a signature of photoinduced electron transfer. Dramatic change in SWCNT electronic structure upon fluorination is also evidenced by UV–vis– near infra red optical absorption spectra, from which the bandgap of about 1.0 eV is derived for F‐SWCNTs. Overall, the experimental results confirm that fluorination efficiently converts metallic SWCNTs into semiconducting ones, and F‐SWCNTs can be used for as an electron acceptor component in OPV devices, in combination with polymer donors. Presently, the performance of P3HT/F‐SWCNT devices is limited by F‐SWCNT aggregation into bundles, which decreases P3HT/F‐SWCNT interface area. [ABSTRACT FROM AUTHOR]

As the 2020 American presidential election approaches, it is worth thinking about the current electoral moment in terms of lessons from the recent and not‐so‐recent past. This article begins with an unlikely analysis. Ordinary life captures the attention of citizens who vote but do not spend their lives 24/7 on social media or cable news or public radio. Ordinary people do not spend their time discussing social policy over dinner. Ordinary people go to dinner—not dinner parties. The ordinary people are the path to victory in any political contest. This article explores the "ordinary" and its relation to politics. [ABSTRACT FROM AUTHOR]

Short‐wave infrared hyperspectral imaging is applied to diagnose and monitor a case of allergic contact dermatitis (ACD) due to poison ivy exposure in one subject. This approach directly demonstrates increased tissue fluid content in ACD lesional skin with a spectral signature that matches the spectral signature of intradermally injected normal saline. The best contrast between the affected and unaffected skin is achieved through a selection of specific wavelengths at 1070, 1340 and 1605 nm and combining them in a pseudo‐red‐green‐blue color space. An image derived from these wavelengths normalized to unaffected skin defines a "tissue fluid index" that may aid in the quantitative diagnosis and monitoring of ACD. Further clinical testing of this promising approach towards disease detection and monitoring with tissue fluid content quantification is warranted. [ABSTRACT FROM AUTHOR]

The Critical Consciousness Scale (CCS) is a recently developed and validated measure for use with low‐income, diverse adolescents. However, research on the psychometric properties of this scale with juvenile legal system‐involved youth is lacking. This study examines the psychometric properties of the critical reflection subscales of the CCS in a cross‐sectional sample of 206 youth (48% girls) involved in the juvenile legal system to investigate (a) the factor structure of the critical reflection subscales of the CCS compared to existing adolescent samples, and (b) the extent to which critical reflection demonstrates measurement equivalence between boys and girls. Findings indicate (a) congruence with the previous literature on critical reflection but for system‐involved girls, and (b) a difference in the structural relationships between perceived inequality and egalitarianism by gender. This study contributes to the nascent, psychometric literature on measures of critical consciousness in an underrepresented and unique adolescent population. [ABSTRACT FROM AUTHOR]

The potential of 2‐(alkylsulfanyl)azine ligands for crystal engineering of functional Ag(I) complexes has been firstly demonstrated. The reaction of AgNO3, AgClO4 and AgOTf with 2‐(alkylsulfanyl)pyridines, ‐pyrimidines, and ‐quinolines gives a series of new Ag(I) compounds that range from mono‐ and dinuclear complexes to chain (1D), layered (2D) and framework (3D) coordination polymers (CPs). 2‐(Alkylsulfanyl)pyridines and ‐pyrimidines, depending on the reaction conditions, are assembled either into molecular complexes or CPs, while 2‐(alkylsulfanyl)quinolines afford dinuclear complexes exclusively. The most of compounds engineered feature site‐specific interactions such as Ag···Ag, Ag···O, and Ag···S ones. The 2‐(methylsulfanyl)quinoline (2‐MeSQn) complex, [Ag2(2‐MeSQn)2(NO3)2], displays room temperature intraligand (IL) phosphorescence, while the 2‐(methylsulfanyl)pyridine‐derived CPs emit dual luminescence expressed by IL fluorescence and phosphorescence. Moreover, cytotoxic activity of the compounds synthesized has been evaluated against hTERT lung fibroblasts, HeLa, MCF7, HepG2 and A549 cancer cells. [ABSTRACT FROM AUTHOR]

The chemistry of metal‐organic frameworks based on cyclodextrins and alkali metals has been extensively investigated in recent years, but coordination polymers with non‐alkali metals have been rarely reported. Here, we describe the synthesis and X‐ray crystallographic characterization of a series of coordination polymers, [Ba(H2O)3(γ‐CD)]Cl2·6H2O (γ‐CD‐Ba1), [Ba(H2O)(γ‐CD)]Cl2·8H2O (γ‐CD‐Ba2), [Sr(H2O)(γ‐CD)](NO3)2·9H2O (γ‐CD‐Sr), [Ca(γ‐CD)2]Cl2·2CH3OH·16H2O (γ‐CD‐Ca), and [Pb(H2O)(γ‐CD)](NO3)2·11H2O (γ‐CD‐Pb), which were obtained by reacting γ‐cyclodextrin with alkaline earth metal ions and Pb2+. The coordination polymers formed from γ‐cyclodextrin and Ca2+ and Ba2+ are obtained for the first time. The only compound in the studied series, γ‐CD‐Ba1, has a 3D structure. The other compounds have layered structures. In the structure of γ‐CD‐Ca, the coordination and number of γ‐cyclodextrin molecules connected to the Ca2+ are different from those determined for a series of isostructural 2D coordination polymers, namely, γ‐CD‐Ba2, γ‐CD‐Sr and γ‐CD‐Pb. The metal‐organic coordination polymer γ‐CD‐Pb exhibits photoluminescence in the near UV‐region (λmax = 345 nm). [ABSTRACT FROM AUTHOR]

Abstract: Manipulating the relaxation pathways of excited states and understanding mechanisms of photochemical reactions present important challenges in chemistry. Here we report a unique zinc(II) complex exhibiting unprecedented interplay between the excitation‐wavelength‐dependent emission, thermally activated delayed fluorescence (TADF) and excited state intramolecular proton transfer (ESIPT). The ESIPT process in the complex is favoured by a short intramolecular OH⋅⋅⋅N hydrogen bond. Synergy between the excitation‐wavelength‐dependent emission and ESIPT arises due to heavy zinc atom favouring intersystem crossing (isc). Reverse intersystem crossing (risc) and TADF are favoured by a narrow singlet–triplet gap, ΔEST≈10 kJ mol−1. These results provide the first insight into how a proton‐transfer system can be modified to show a synergy between the excitation‐wavelength‐dependent emission, ESIPT and TADF. This strategy offers new perspectives for designing ESIPT and TADF emitters exhibiting tunable excitation‐wavelength‐dependent luminescence. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of a zig‐zag oxygen‐doped molecular rhombic ribbon has been achieved. This includes oxidative C−C and C−O bond formations that allowed the stepwise elongation and planarization of an oxa‐congener of 2,7‐periacenoacene. X‐ray diffraction analysis corroborated the flat structure and the zig‐zag topology of the O‐doped edges. Photophysical and electrochemical investigations showed that the extension of the peri‐xanthenoxanthene (PXX) into the molecular ribbon induces a noticeable shrinking of the molecular band gap devised by a rising of the HOMO energy level, a desirable property for p‐type organic semiconductors. [ABSTRACT FROM AUTHOR]

Rapid detection of multifocal cancer without the use of complex imaging schemes will improve treatment outcomes. In this study, dynamic fluorescence imaging was used to harness differences in the perfusion kinetics of near‐infrared (NIR) fluorescent dyes to visualize structural characteristics of different tissues. Using the hydrophobic nontumor‐selective NIR dye cypate, and the hydrophilic dye LS288, a high tumor‐to‐background contrast was achieved, allowing the delineation of diverse tissue types while maintaining short imaging times. By clustering tissue types with similar perfusion properties, the dynamic fluorescence imaging method identified secondary tumor locations when only the primary tumor position was known, with a respective sensitivity and specificity of 0.97 and 0.75 for cypate, and 0.85 and 0.81 for LS288. Histological analysis suggests that the vasculature in the connective tissue that directly surrounds the tumor was a major factor for tumor identification through perfusion imaging. Although the hydrophobic dye showed higher specificity than the hydrophilic probe, use of other dyes with different physical and biological properties could further improve the accuracy of the dynamic imaging platform to identify multifocal tumors for potential use in real‐time intraoperative procedures. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to develop a novel optical imaging system for detecting protoporphyrin IX (PpIX) autofluorescence, to prove that PpIX autofluorescence is as useful as 5-aminolevulinic acid (5-ALA)-induced fluorescence for detecting and localizing cervical cancer, and to monitor the change in PpIX autofluorescence or induced PpIX fluorescence before, during, and after photodynamic therapy (PDT). Methods TC-1 cells - highly tumorigenic cells immortalized using human papillomavirus type 16 proteins E6 and E7 - were subcutaneously grafted into the thighs of nude mice. The suspected tumor tissues were visualized using autofluorescence imaging and induced fluorescence imaging under 5-ALA administration. When the 5-ALA-induced PpIX was sufficiently accumulated in tumor tissues, PDT was performed using a 635-nm laser. We observed the change in fluorescence intensity during PDT. For 3 weeks after PDT, we monitored tumor remission by using white-light imaging and fluorescence imaging. Results The transplanted cells were visualized by PpIX autofluorescence, which was induced by heme synthesis. After 5-ALA administration, PpIX could be targeted by using PDT, which decreased PpIX autofluorescence. Photobleaching is useful for monitoring PDT dosimetry and for determining the photodynamic response to therapy. Conclusion PpIX autofluorescence clearly differentiated the tumor from adjacent normal tissues. The results of PpIX autofluorescence imaging and 5-ALA-induced fluorescence imaging were identical. PpIX autofluorescence imaging is a simple and cost-effective cervical cancer screening method that could be performed during or after PDT to ensure effective treatment or remission as a change in fluorescence intensity can be observed in real time without a blinding effect. [ABSTRACT FROM AUTHOR]

Geotemporal information, information associated with geographical space and time, has always been critical to climate and environmental science. However, this information is certainly not universally or easily accessible. In fact, obtaining and using geotemporal information often comes with a considerable technical overheads, impeding research progress. To address this, we introduce FetchClimate: a cloud service designed to provide easy, universal access to geotemporal information. FetchClimate enables and accelerates the use of geotemporal information by enabling it to be accessed programmatically from a Web service (such as the statistical software R) or non-programmatically using a Web browser. We intend the service to accelerate the pace of ecological and environmental research by eliminating the technical overheads currently needed to obtain geotemporal information. The software, online manual, and user support are freely available at < >. [ABSTRACT FROM AUTHOR]

Through the simultaneous use of three orthogonal dynamic covalent reactions, namely disulfide, boronate, and acyl hydrazone formation, we conceived a facile and versatile protocol to spatially organize tailored chromophores, which absorb in the blue, red, and yellow regions, on a preprogrammed α-helix peptide. This approach allowed the assembly of the dyes in the desired ratio and spacing, as dictated by both the relative positioning and distribution of the recognition units on the peptide scaffold. Steady-state UV/Vis absorption and emission studies suggest an energy transfer from the yellow and red donors to the blue acceptor. A molecular dynamics simulation supports the experimental findings that the helical structure is maintained after the assembly and the three dyes are confined in defined conformational spaces. [ABSTRACT FROM AUTHOR]

Neurexins (NXs) and neuroligins (NLs) are cell adhesion molecules that are localized at opposite sites of synaptic membranes. They interact with each other to promote the assembly, maintenance, and function of synapses in the central nervous system. Both NX and NL are cleaved from a membrane-attached intracellular domain in an activity-dependent manner, generating the soluble ectodomain of NX or NL. Expression of the NX1 and NX3 genes in the brain appears to be regulated by a schizophrenia-related protein, DISC1. Here, we show that soluble ecto-NX1β can regulate the expression of DISC1 and induce signaling downstream of DISC1. We also show that NL1 binds to a well-characterized DISC1 interaction partner, Kal-7, and this interaction can be compromised by DISC1. Our results indicate that the NX/NL synaptic complex is intrinsically involved in the regulation of DISC1 function, thus contributing to a better understanding of the pathology of schizophrenia. [ABSTRACT FROM AUTHOR]

In vivo optical imaging with near-infrared (NIR) probes is an established method of diagnostics in preclinical and clinical studies. However, the specificities of these probes are difficult to validate ex vivo due to the lack of NIR flow cytometry. To address this limitation, we modified a flow cytometer to include an additional NIR channel using a 752 nm laser line. The flow cytometry system was tested using NIR microspheres and cell lines labeled with a combination of visible range and NIR fluorescent dyes. The approach was verified in vivo in mice evaluated for immune response in lungs after intratracheal delivery of the NIR contrast agent. Flow cytometry of cells obtained from the lung bronchoalveolar lavage demonstrated that the NIR dye was taken up by pulmonary macrophages as early as 4-h post-injection. This combination of optical imaging with NIR flow cytometry extends the capability of imaging and enables complementation of in vivo imaging with cell-specific studies. © 2015 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

We have developed a novel design of optical nanothermometers that can measure the surrounding temperature in the range of 20-85 °C. The nanothermometers comprise two organic fluorophores encapsulated in a crosslinked polymethacrylate nanoshell. The role of the nanocapsule shell around the fluorophores is to form a well-defined and stable microenvironment to prevent other factors besides temperature from affecting the dyes' fluorescence. The two fluorophores feature different temperature-dependent emission profiles; a fluorophore with relatively insensitive fluorescence (rhodamine 640) serves as a reference whereas a sensitive fluorophore (indocyanine green) serves as a sensor. The sensitivity of the nanothermometers depends on the type of nanocapsule-forming lipid and is affected by the phase transition temperature. Both the fluorescence intensity and the fluorescence lifetime can be utilized to measure the temperature. [ABSTRACT FROM AUTHOR]

1,3,7,8-Tetraphenyl-4,8-dihydro-1 H-imidazolo[4,5 g][1,2,4]benzotriazin-4-yl ( 5), 8-(4-bromophenyl)-1,3,7-triphenyl-4,8-dihydro-1 H-imidazolo[4,5 g][1,2,4]benzotriazin-4-yl ( 6), and 8-(4-methoxyphenyl)-1,3,7-triphenyl-4,8-dihydro-1 H-imidazolo[4,5 g][1,2,4]benzotriazin-4-yl ( 7) were characterized by using X-ray diffraction crystallography, variable-temperature magnetic susceptibility studies, and DFT calculations. Radicals 5- 7 pack in 1 D π stacks made of radical pairs with alternate short and long interplanar distances. The magnetic susceptibility ( χ vs. T) of radicals 5 and 6 exhibit broad maxima at (50±2) and (50±4) K, respectively, and are interpreted in terms of an alternating antiferromagnetic Heisenberg linear chain model with average exchange-interaction values of J=−31.3 and −35.4 cm−1 ( gsolid=2.0030 and 2.0028) and an alternation parameter a=0.15 and 0.38 for 5 and 6, respectively. However, radical 7 forms 1 D columns of radical pairs with alternating distances; one of the interplanar distances is significantly longer than the other, which decreases the magnetic dimensionality and leads to discrete dimers with a ferromagnetic exchange interaction between the radicals (2 J=23.6 cm−1, 2 zJ′=−2.8 cm−1, gsolid=2.0028). Magnetic exchange-coupling interactions in 1,2,4-benzotriazinyl radicals are sensitive to the degree of slippage and inter-radical separation, and such subtle changes in structure alter the fine balance between ferro- and antiferromagnetic interactions. [ABSTRACT FROM AUTHOR]

The stable free radical polymerization ( SFRP) process based on (1,3-diphenyl-1,4-dihydro-1,2,4-benzotriazin-4-yl), the so-called 'Blatter radical', and several C-7 substituted derivatives is introduced for the first time for the polymerization of styrene. Polystyrenes characterized by polydispersity indices in the 1.05 − 1.27 range were obtained in the presence of the Blatter radical and its derivatives containing CF3, Ph, Fur-2-yl and 4- PhC6H4 substituents, while polymerization proceeded either in a non-controlled manner or in very low polymerization yields in the presence of derivatives containing halogen (Cl, Br, I) substituents. This preliminary investigation, demonstrating the potential use of the Blatter radical and its derivatives in mediated SFRP, creates new opportunities to design and develop radicals to optimize performance in such polymerization processes. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Near-infrared heptamethine cyanine dye is functionalized with pyrazole derivatives at the meso-position to induce pH-dependent photophysical properties. The presence of pyrazole unsubstituted at 1N-position is essential to induce pH-dependent fluorescence intensity and lifetime changes in these dyes. Replacement of meso-chloro group of cyanine dye IR820 with 1N-unsubstituted pyrazole resulted in the pH-dependent fluorescence lifetime changes from 0.93 ns in neutral media to 1.27 ns in acidic media in DMSO. Time-resolved emission spectra (TRES) revealed that at lower pH, the pyrazole consists of fluorophores with two distinct lifetimes, which cor-responds to pH-sensitive and non- pH-sensitive species. In contrast, 1N-substituted pyrazoles do not exhibit pH response, suggesting excited state electron transfer as the mechanism of pH-dependent fluorescence lifetime sensitivity for this class of compounds. [ABSTRACT FROM AUTHOR]

Csr is a conserved global regulatory system that controls expression of several hundred Escherichia coli genes. CsrA protein represses translation of numerous genes by binding to mRNA and inhibiting ribosome access. CsrA also activates gene expression, although an activation mechanism has not been reported. CsrA activates flhDC expression, encoding the master regulator of flagellum biosynthesis and chemotaxis, by stabilizing the m RNA. Computer modelling, gel mobility shift and footprint analyses identified two CsrA binding sites extending from positions 1-12 ( BS1) and 44-55 ( BS2) of the 198 nt flhDC leader transcript. flhD ′-′ lacZ expression was reduced by mutations in csrA and/or the CsrA binding sites. The position of BS1 suggested that bound CsrA might inhibit 5′ end-dependent RNase E cleavage of flhDC m RNA. Consistent with this hypothesis, CsrA protected flhDC leader RNA from RNase E cleavage in vitro and protection depended on BS1 and BS2. Primer extension studies identified flhDC decay intermediates in vivo that correspond to in vitro RNase E cleavage sites. Deletion of these RNase E cleavage sites resulted in increased flhD ′-′ lacZ expression. Data from m RNA decay studies and quantitative primer extension assays support a model in which bound CsrA activates flhDC expression by inhibiting the 5′ end-dependent RNase E cleavage pathway. [ABSTRACT FROM AUTHOR]

Neurexin-1 (NRXN1) and neuroligin-1 (NLGN1) are synaptic cell adhesion molecules that connect pre- and postsynaptic neurons at synapses and mediate signaling across the synapse, which modulates synaptic activity and determines the properties of neuronal networks. Defects in the genes encoding NLGN1 have been linked to cognitive diseases such as autism. The roles of both NRXN1 and NLGN1 during synaptogenesis have been studied extensively, but little is known about the role of these molecules in neuritogenesis, which eventually results in neuronal circuitry formation. The present study investigated the neuritogenic effect of NLGN1 in cultures of hippocampal neurons. Our results show that NLGN1, both in soluble and membrane-bound forms, induces neurite outgrowth that depends on the interaction with NRXN1β and on activation of fibroblast growth factor receptor-1. In addition, we demonstrate that a synthetic peptide, termed neurolide, which is modeled after a part of the binding interface of NLGN1 for NRXN1β, can bind to NRXN1β and mimic the biological properties of NLGN1 in vitro. [ABSTRACT FROM AUTHOR]

J. Neurochem. (2012) 121, 915-923. Abstract Apart from its hematopoietic activity, erythropoietin (EPO) is also known as a tissue-protective cytokine. In the brain, EPO and its receptor are up-regulated in response to insult and exert pro-survival effects. EPO binds to its receptor (EPOR) via high- and low-affinity binding sites (Sites 1 and 2, respectively), inducing conformational changes in the receptor, followed by the activation of downstream signaling cascades. Based on the crystal structure of the EPO:EPOR2 complex, we designed a peptide, termed Epobis, whose sequence encompassed amino acids from binding Site 1. The present study shows that the Epobis peptide specifically binds to EPOR and induces neurite outgrowth from primary neurons in an EPOR-expression dependent manner. Furthermore, Epobis promoted the survival of hippocampal and cerebellar neuronal cultures after kainate treatment and KCl deprivation, respectively. Thus, we identified a new functional agonist of EPOR with the potential to promote neuroregeneration and neuroprotection. [ABSTRACT FROM AUTHOR]

Valproic acid (VPA) is a known teratogen. In the present study, the effects of VPA and seven VPA derivatives with different teratogenic potencies (isobutyl-, 5-methyl-, ethyl-, propyl-, butyl-, pentyl- and hexyl-4 -yn-VPA) were investigated in L929 cells in vitro. Evaluated end-points included changes in cell proliferation, growth, cell cycle distribution, morphology, speed, glycogen synthase kinase-3β (GSK-3β) and Erk1/2 phosphorylation, and histone H3 acetylation. Changes in proliferation, growth, speed, Erk1/2 and GSK-3β-Tyr216 phosphorylation, and H3 acetylation were significantly associated with the teratogenic potencies of the VPA derivatives. However, in contrast to changes in Erk1/2 phosphorylation and H3 acetylation, significant changes in GSK-3β phosphorylation could only be obtained in response to prolonged incubation at high drug concentration. There was an association between changes in H3 acetylation and GSK-3β-Tyr216 phosphorylation, whereas none of these end-points were associated with changes in Erk1/2 phosphorylation. These results suggest that the teratogenic potencies of VPA and VPA derivatives are related to effects on both Erk1/2 and histone deacetylase activities, whereas changes in GSK-3β activity are possibly a secondary effect. [ABSTRACT FROM AUTHOR]

Epithelial ovarian carcinoma (EOC) is an aggressive neoplasm, which mainly disseminates to organs of the peritoneal cavity, an event mediated by molecular mechanisms that remain elusive. Here, we investigated the expression and functional role of neural cell adhesion molecule (NCAM), a cell surface glycoprotein involved in brain development and plasticity, in EOC. NCAM is absent from normal ovarian epithelium but becomes highly expressed in a subset of human EOC, in which NCAM expression is associated with high tumour grade, suggesting a causal role in cancer aggressiveness. We demonstrate that NCAM stimulates EOC cell migration and invasion in vitro and promotes metastatic dissemination in mice. This pro-malignant function of NCAM is mediated by its interaction with fibroblast growth factor receptor (FGFR). Indeed, not only FGFR signalling is required for NCAM-induced EOC cell motility, but targeting the NCAM/FGFR interplay with a monoclonal antibody abolishes the metastatic dissemination of EOC in mice. Our results point to NCAM-mediated stimulation of FGFR as a novel mechanism underlying EOC malignancy and indicate that this interplay may represent a valuable therapeutic target. [ABSTRACT FROM AUTHOR]