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A modular assembly of water-soluble diarylethenes (DAEs), applicable as biomarkers for optical nanoscopy, is reported. Reversibly photoswitchable 1,2-bis(2-alkyl-6-phenyl-1-benzothiophene-1,1-dioxide-3-yl)perfluorocyclopentenes possessing a fluorescent "closed" form were decorated with one or two methoxy group(s) attached to the para-position(s) of phenyl ring(s) and two, four, or eight carboxylic acid groups. Antibody conjugates of these DAEs feature low aggregation, efficient photoswitching in aqueous buffers, specific staining of cellular structures, and photophysical properties (high emission efficiencies and low cycloreversion quantum yields) enabling their application in superresolution microscopy. Images of tubulin, vimentin, and nuclear pore complexes are presented. The superresolution images can also be acquired by using solely 488 nm light without additional photoactivation with UV light. These DAEs exhibit reversible photoswitching without requiring any additives to the imaging media and open new paths toward the modular design of fluorescent dyes for bioimaging with optical superresolution.

Compact “push–pull” photochromic diaryethenes (DAEs) with unsymmetric oxidation pattern of the benzothiophene core display multicolour fluorescence switching, as a result of dual emission from both “open” and “closed” forms. These DAEs also present an unprecedented photo-fatigue resistance.

Antecedentes: la hemicolectomía derecha laparoscópica con abordaje suprapúbico (HDLS) y empleo de tecnología. En los pacientes con cáncer de colon con metástasis hepáticas sincrónicas (CCMHS), la resección completa del tumor primario con las metástasis es la única opción de tratamiento con intención curativa. Se conocen varios informes de series de casos en el mundo; sin embargo, no existe ningún estudio aleatorizado controlado. Objetivo: el objetivo es evaluar la factibilidad y seguridad del abordaje laparoscópico simultáneo de la resección del tumor primario de colon y de la metástasis hepática. Material y métodos: es un estudio retrospectivo; a tal fin se recolectaron todos los pacientes con sospecha de CCMHS abordados por laparoscopia con intención de resección simultánea del tumor primario de colon con las metástasis hepáticas. Se analizaron variables preoperatorias, operatorias, resultados a corto y largo plazo, y anatomopatológicas. Resultados: en el período de estudio se realizaron 89 resecciones hepáticas laparoscópicas (RHL). En 28 pacientes se realizó ‒en forma simultánea con la RHL‒ otro procedimiento, en 21 de los cuales fue una colectomía laparoscópica. El tiempo quirúrgico promedio total de los dos procedimientos llegó a 407 minutos. El promedio de días de estadía hospitalaria fue de 8 días. No hubo mortalidad en la serie, y la morbilidad global fue del 71%, pero un solo caso con morbilidad mayor. La sobrevida global y la sobrevida libre de recurrencia a los 3 años fue de 55,2% y 16,3%, respectivamente. Conclusión: Esta es la primera publicación acerca del tema en nuestro país. Podemos decir que, en casos bien seleccionados, el abordaje laparoscópico simultáneo es factible de realizar, con aceptable morbimortalidad y sin comprometer los resultados oncológicos. Background: In patients with colorectal cancer with synchronous liver metastases (CLM), complete resection of the primary tumor with the metastases is the only option for curative treatment. Several case series have been reported but no randomized controlled trials have been published. Objective: The aim was to evaluate if the simultaneous laparoscopic resection of the primary colon tumor and liver metastases is feasible and safe. Material and methods: A retrospective study was conducted with patients with suspected CLM scheduled for simultaneous laparoscopic resection of the primary tumor of the colon and liver metastases. The preoperative and operative variables, short- and long-term outcomes and pathological variables were analyzed. Results: A total of 89 laparoscopic liver resections (LLR) were performed during the study period. In 28 patients, LLR was simultaneous with other procedures, 21 of which corresponded to laparoscopic colon resection. Mean surgical time for both procedures was 407 minutes. Mean hospital length of stay was 8 days. None of the patients died and overall morbidity rate was 71% with only one major complication. Overall survival and relapse-free survival at three years was 55.2% and 16.3%, respectively. Conclusion: This is the first publication analyzing this approach in our country. In well selected cases, the simultaneous laparoscopic approach is feasible, with low morbidity and mortality and acceptable oncological results.

We present a new series of photochromic 1,2-bis(2-ethylbenzo[b]thiophen-3-yl)perfluorocyclopentenes with an oxidized benzothiophene core (O) or a nonoxidized one, decorated with mono- (Th1) and bithiophene (Th2) units attached to positions 6 and 6′ (Sy = symmetric) or only to position 6 (As = asymmetric). “Oxidized” compounds have highly fluorescent closed forms emitting in the visible region (yellow to red). The dyes with nonoxidized benzothiophenes possess fluorescent open forms with rather low emission efficiency. The photoswitching kinetics was studied at several wavelengths with UV and visible light. New diarylethenes underwent ring-closure reactions by irradiation with UV light (365 nm, 405 nm), and the reversible ring-opening by irradiation with visible light (470 nm, 530 nm). The on-switching of fluorescence due to the ring-closure reaction was observed also with visible light of 470 nm (to an extent of 10% for compound SyOTh1) and attributed to the Urbach tail effect. Due to a high degree of fluorescence modulation (>270), good fatigue resistance and large fluorescence quantum yield, compound SyOTh1 emerged as a candidate for single-molecule based super-resolution fluorescence microscopy.

Low photostability in aqueous solutions is the main drawback of synthetic photochromic dyes, which limits their switching performance and utility in biology, medicine, and life sciences. Even the most promising photochromes—reversibly photoswitchable diarylethenes (DAEs) with fluorescent “closed” forms—are known to undergo only several tens (typically 20–30) of switching cycles in aqueous solutions. In this work, we introduce water-soluble and highly photostable 1,2-[bis(2-ethyl/2-isobutyl-1-benzothiophene-1,1-dioxide-6-phenyl-3-yl)]perfluorocyclopentenes decorated with four −CONHC(CH2R)3 residues capped with 12 carboxylic acid groups (R = CH2CO2H, O(CH2)2CO2H). Under irradiation with UV (365 nm) and visible light (470 nm), they provide several hundred (for the “rapid” DAEs with isobutyl groups, up to 1000) full switching cycles in aqueous solutions without exclusion of air oxygen (outperforming the photoswitchable and fluorescent protein Dreiklang). The new branching approach based on secondary carboxamides with N-tert-alkyl residues decorated with polar groups may serve as a blueprint for the design of highly fatigue resistant and reversibly photoswitchable fluorescent probes applicable in life sciences as aqueous solutions.

Electronic energy transfer (EET) between chromophores is of fundamental importance for many biological processes and optoelectronic devices. However, common models fall short in fully describing the process, especially in bichromophoric model systems with a donor and acceptor connected by a rigid linker providing perpendicular geometries. Herein, we report a novel strategy for preparing bichromophores containing adamantane or 2-(2-adamantylidene)adamantane as rigid spacers, providing a fixed distance between chromophores, and their parallel or perpendicular arrangement without chromophore rotation. New fluorophores were developed and linked via spiroatoms. Bichromophores with identical (blue-blue) or different (blue-red) chromophores were synthesized, either in orthogonal or parallel geometry. These were characterized by absorption/fluorescence spectroscopy, time-resolved fluorescence anisotropy, and fluorescence antibunching measurements. Based on the Förster point-dipole approximation, EET efficiencies were estimated by using geometrical parameters from (time-dependent) density functional calculations. For bichromophores with parallel geometry, the predicted EET efficiencies were near unity and fit the measurements. In spite of estimated values around 0.4 and 0.5, 100 % efficiency was observed also for bichromophores with orthogonal geometry. The new rigid scaffolds presented here open new possibilities for the synthesis of bichormophores with well-defined parallel or perpendicular geometry.

Reversibly photoswitchable 1,2‐bis(2‐ethyl‐6‐phenyl‐1‐benzothiophene‐1,1‐dioxide‐3‐yl)perfluorocyclopentenes (EBT) having fluorescent “closed” forms were decorated with four or eight carboxylic groups and attached to antibodies. Low aggregation, efficient photoswitching in aqueous buffers, specific staining of cellular structures, and good photophysical properties were demonstrated. Alternating light pulses of UV and blue light induce numerous reversible photochemical transformations between two stables states with distinct structures. Using relatively low light intensities, EBTs were applied in biology‐related super‐resolution microscopy based on the reversible saturable (switchable) optical linear fluorescence transitions (RESOLFT) and demonstrated optical resolution of 75 nm.

Recent political changes suggest that Argentina has started a process in which demands for greater transparency in public affairs require a redesign of decision-making processes. Nevertheless, the most challenging feature in the Argentine political-institutional environment is the lack of incentives for introducing better regulation policies. This situation is a consequence – inter alia – of political instability and recurrent economic crises. This article analyses the current situation in Argentina regarding the concept of rational law-making, from the perspective of evidence-based legislative process and procedural judicial review. We conclude that even acknowledging the weight of the longstanding tradition of judicial deference to the legislature and the absence of procedural standards that guide the legislative process, certain judicial decisions hint at the beginning of a path in which traditional constitutional review – basically substantive – incorporates judicial review of rational law-mak...

Chaotic sequences are good candidates to replace random sequences in many digital electronic applications, this is due to their stochastic appearance and, under certain considerations, easy hardware implementation. On the other hand, Compressed Sensing (CS) technique allows the efficient acquisition and reconstruction of signals from a smaller number of samples than that required by Shannon-Nyquist sampling theorem. A critical point in this technique is the choice of sampling implementation, usually random sequences are used. These sequences are computationally expensive to generate, so in this work the use of chaotic sequences is studied. This paper validates by the design and hardware implementation in a PSoC (Programmable System-on-Chip), Zedboard FPGA (Field-Programmable Gate Array) a signal acquisition system employing chaotic Compressed Sensing. Performance quantifiers of the implemented system are proposed and the results obtained are reported, which show that the chaotic systems present a behavior comparable to the classic ones.

Photoactivatable rhodamine spiroamides and spirocyclic diazoketones emerged recently as synthetic markers applicable in multicolor super-resolution microscopy. However, their applicability in single molecule localization microscopy (SMLM) is often limited by aggregation, unspecific adhesion, and low reactivity caused by insufficient solubility and precipitation from aqueous solutions. We report here two synthetic modifications increasing the polarity of compact polycyclic and hydrophobic labels decorated with a reactive group: attachment of 3-sulfo-l-alanyl-beta-alanine dipeptide (a "universal hydrophilizer") or allylic hydroxylation in photosensitive rhodamine diazoketones (and spiroamides). The super-resolution images of tubulin and keratin filaments in fixed and living cells exemplify the performance of "blinking" spiroamides derived from N, N, N', N'-tetramethyl rhodamine.

Sequential adsorption of PdCl42- within weak polyelectrolyte layer-by-layer (LbL) self-assembled multilayer films with further electrochemical reduction to yield Pd0 nanoparticles (Pd-NPs) has been demonstrated. The electrocatalytic hydrogenation (ECH) of model molecules such as acetophenone and benzophenone on Pd-NPs of different sizes (6 to 35 nm) and bulk Pd crystal surface in hydroalcoholic acid solution has been investigated. Distribution of reaction products (secondary alcohols and alkanes) and faradaic yield was systematically investigated. While the polyelectrolyte multilayers act as nanoreactors by confining PdCl42- ions and preventing the formation of large crystals, their presence also alters the hydrogenation reaction and therefore heat treated surfaces showed only the effect of nanocrystal size on the reaction selectivity and faradaic yield. This journal is Fil: Villalba, Matias Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Bossi, Mariano Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Calvo, Ernesto Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina

In this work, we present a software and hardware implementation in a PSoC (Programmable System-on-Chip) of a signal acquisition and reconstruction system. The design combines two novel techniques: data compression in the analog domain (Xampling) and compressed sensing (CS). The developed system allows an efficient reconstruction of signals from a smaller number of samples than the required by the Shannon-Nyquist sampling theorem. A critical point in CS technique is the choice of the sampling matrix, which is classically constructed using random sequences. These sequences are computationally expensive to generate, so in this work, we study the usage of chaotic sequences. In addition to that, we propose performance quantifiers to evaluate the modeled system. Finally, we conclude that the system implemented with chaos have a similar behavior compared to the conventional system.

Caged rhodamine dyes (Rhodamines NN) of five basic colors were synthesized and used as “hidden” markers in subdiffractional and conventional light microscopy. These masked fluorophores with a 2-diazo-1-indanone group can be irreversibly photoactivated, either by irradiation with UV- or violet light (one-photon process), or by exposure to intense red light (λ∼750 nm; two-photon mode). All dyes possess a very small 2-diazoketone caging group incorporated into the 2-diazo-1-indanone residue with a quaternary carbon atom (C-3) and a spiro-9H-xanthene fragment. Initially they are non-colored (pale yellow), non-fluorescent, and absorb at λ=330–350 nm (molar extinction coefficient (ε)≈104 M−1 cm−1) with a band edge that extends to about λ=440 nm. The absorption and emission bands of the uncaged derivatives are tunable over a wide range (λ=511–633 and 525–653 nm, respectively). The unmasked dyes are highly colored and fluorescent (ε= 3–8×104 M−1 cm−1 and fluorescence quantum yields (ϕ)=40–85 % in the unbound state and in methanol). By stepwise and orthogonal protection of carboxylic and sulfonic acid groups a highly water-soluble caged red-emitting dye with two sulfonic acid residues was prepared. Rhodamines NN were decorated with amino-reactive N-hydroxysuccinimidyl ester groups, applied in aqueous buffers, easily conjugated with proteins, and readily photoactivated (uncaged) with λ=375–420 nm light or intense red light (λ=775 nm). Protein conjugates with optimal degrees of labeling (3–6) were prepared and uncaged with λ=405 nm light in aqueous buffer solutions (ϕ=20–38 %). The photochemical cleavage of the masking group generates only molecular nitrogen. Some 10–40 % of the non-fluorescent (dark) byproducts are also formed. However, they have low absorbance and do not quench the fluorescence of the uncaged dyes. Photoactivation of the individual molecules of Rhodamines NN (e.g., due to reversible or irreversible transition to a “dark” non-emitting state or photobleaching) provides multicolor images with subdiffractional optical resolution. The applicability of these novel caged fluorophores in super-resolution optical microscopy is exemplified. Fil: Belov, Vladimir N.. Max Planck Institute for Biophysical Chemistry ; Alemania Fil: Mitronova, Gyuzel Yu.. Max Planck Institute for Biophysical Chemistry ; Alemania Fil: Bossi, Mariano Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Boyarskiy, Vadim P.. St. Petersburg State University; Rusia Fil: Hebisch, Elke. Max Planck Institute for Biophysical Chemistry ; Alemania Fil: Geisler, Claudia. Max Planck Institute for Biophysical Chemistry ; Alemania Fil: Kolmakov, Kirill. Max Planck Institute for Biophysical Chemistry ; Alemania Fil: Wurm, Christian A.. Max Planck Institute for Biophysical Chemistry ; Alemania Fil: Willig, Katrin I.. Max Planck Institute for Biophysical Chemistry ; Alemania Fil: Hell, Stefan W.. Max Planck Institute for Biophysical Chemistry ; Alemania

Spectral stability of small-molecule fluorescent probes is required for correct interpretation and reproducibility of multicolor fluorescence imaging data, in particular under high (de)excitation light intensities of super-resolution imaging or in single-molecule applications. We propose a synthetic approach to a series of spectrally stable rhodamine fluorophores based on sequential Ru- and Cu-catalyzed transformations, evaluate their stability against photobleaching and photoconversion in the context of other fluorophores using chemometric analysis, and demonstrate chemical reactivity of fluorophore photoproducts. The substitution patterns providing the photoconversion-resistant triarylmethane fluorophores have been identified, and the applicability of nonbluing labels in live-cell STED nanoscopy is demonstrated.