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The chemical reduction within a family of organic selenocyanates, as masked selenols, using reducing agents, such as Rongalite, sodium dithionite, and sodium thiosulfate is investigated. Using Rongalite, the corresponding diselenides were obtained quantitatively and selectively in very good to excellent yields (51-100 %) starting from alkyl, aryl, and benzyl selenocyanates. The scope of the reaction is unaffected by the electronic nature of the substituents. Furthermore, the reducing agent, Rongalite, is compatible with hydrolysable and reducing-sensitive functional groups. Additionally, a simple methodology employing the in-situ generated benzyl selenolate anion (PhCH2Se-) to promote aliphatic nucleophilic substitution, epoxide ring opening, and Michael addition reactions has been developed; thus, extending the structural diversity of the synthesized selenium derivatives.

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OBJECTIVES: The aims were to estimate the frequency of axial spondyloarthritis (axSpA) in women and to analyze the clinical, laboratory, and imaging differences with respect to men at the time of diagnosis. METHODS: Consecutive patients older than 18 years with a diagnosis of axSpA admitted to the "Reumacheck" SpA program were included between 2017 and 2022. At baseline, all patients underwent clinical assessment, laboratory tests including C-reactive protein and human leukocyte antigen B27, and imaging (plain radiography and magnetic resonance imaging of sacroiliac joints, and ultrasound of heel entheses). All evaluators were blinded to the results of the other evaluations. RESULTS: One hundred sixteen patients with a diagnosis of axSpA were included. The frequency at diagnosis in women was 61.55%. In the univariate analysis, the significant differences between women and men at diagnosis of axSpA were good response to nonsteroidal anti-inflammatory drugs, elevated C-reactive protein, New York Criteria (+), enthesis ultrasound (+), years of education, number of swollen joints, erythrosedimentation rate, and the very low frequency of bone bridges in the magnetic resonance imaging of the sacroiliac joints. In the logistic regression analysis, the dependent variable was "men," and the only feature that was independently associated was having radiographic compromise according to the New York criteria (odds ratio, 2.6). CONCLUSIONS: The frequency of axSpA in women was 61.55%; clinical, laboratory, and imaging differences were observed. Women experienced less radiographic compromise.

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Sustainable approaches for the synthesis of 2-substituted benzothiazoles are sought after for their use in organic chemistry, bioorganic chemistry, and industrial applications. Here, we described a visible light-driven photoredox catalytic cyclization of thioanilides to afford 2-substituted benzothiazoles using riboflavin as a photocatalyst, where oxygen is used as a clean oxidant and ethanol as a greener solvent. These results provide a new photochemical route for environmentally benign synthesis.

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The application of photocatalysis for organic synthesis, both in the laboratory and on an industrial scale, will depend on the achieving of good yields and the ease with which it can be applied. Selective irradiation of the photocatalyst with LED light has made it possible to activate the reactions easily, without the need for UV or heat filters. However, a common problem is the need to separate the photocatalyst from the reaction products through extraction and chromatography isolation processes. These procedures make it difficult to recover and reuse the catalyst, which is not compatible with scale-up applications. Photocatalysts attached to heterogeneous supports resulted in an alternative, which facilitates their removal and reuse. In this study, we use chromatographic silica gel as a low-cost heterogeneous support to bind photosensitizers such as Riboflavin or Eosin Y. The modified silica gel was analyzed by FTIR-ATR and diffuse reflectance UV-visible spectroscopy, thermogravimetric analysis, and optical microscopy. These hybrid materials have a suitable size for easy separation by decantation and were found to be photoactive against two photooxidation reactions. These easy-to-handle materials open the door to effective applications for photoinduced organic synthesis methods at medium to large scale.

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A variety of phenols have been obtained in aqueous media with moderate to excellent chemical yields (≤100%) by using arylboronic acids and esters as substrates, a robust CdS-TiO2 nanohybrid as a heterogeneous photocatalyst, visible light irradiation (467 nm), and an O2-saturated atmosphere. The nanohybrid was prepared through a linker-assisted methodology that uses mercapto alkanoic acids as the organic linkers. The nanohybrid showed improved photocatalytic activity in the hydroxylation of substituted arylboronic acids and phenyl boronic esters compared with that of pristine CdS quantum dots. The nanohybrid can be reused in up to five photocatalytic cycles with ∼90% of its outstanding activity preserved.

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Introducción: la disfunción sexual (DS) es común entre las mujeres con enfermedades crónicas, incluyendo esclerosis sistémica (ES). Se ha asociado con características como la duración de la enfermedad, dolor, disminución de la actividad funcional, entre otras. Desde nuestro conocimiento, aún no contamos con datos locales. Objetivos: evaluar la frecuencia de DS en mujeres con ES; describir las características sociodemográficas, clínicas y psicológicas asociadas con la DS en mujeres con ES. Materiales y métodos: estudio observacional, analítico y de corte transversal. Se incluyeron mujeres de entre 20 y 59 años con diagnóstico de ES, según los criterios de clasificación del European League Against Rheumatism/American College of Rheumatology (ACR/EULAR 2013). Se excluyeron pacientes con enfermedades crónicas no controladas, otras patologías reumatológicas autoinmunes, e inactividad sexual o patología genitourinaria no relacionadas a ES en las últimas 4 semanas. La DS se evaluó con la versión en español del cuestionario índice de función sexual femenina (Female sexual function index, FSFI). Resultados: se incluyeron 56 pacientes. El 78,57% presentó DS y 19,64% era sexualmente inactiva debido a la enfermedad. Escala visual análoga (EVA) de fatiga (coeficiente β: -0,08, IC 95%: -0,14 a -0,02; p<0,01), edad (coeficiente β: -0,23, IC 95%: -0,40 a -0,05; p=0,01) y fibromialgia (coeficiente β: -11,90, IC 95%: -17,98 a -5,82; p<0,01) mostraron una asociación significativa e independiente con DS en el análisis multivariado. Conclusiones: la DS es frecuente entre las mujeres con ES, y las pacientes más jóvenes, sin fibromialgia y con menor fatiga presentaron una mejor funcionalidad sexual.

Introduction: sexual impairment (SI) is common among women with chronic diseases, including systemic sclerosis (SSc). It has been associated with characteristics such as the duration of the disease, pain, decreased functional activity, among others. To the best of our knowledge, we still do not have local data. Objectives: to evaluate the frequency of SI in women with SSc. To describe the sociodemographic characteristics, disease itself and psychological items associated with SI in women with SSc. Materials and methods: observational, analytical, cross-sectional study. We included women between 20 and 59 years diagnosed with SSc according to 2013 classification criteria ACR/EULAR. We excluded patients with uncontrolled chronic diseases or other autoimmune rheumatologic diseases and patients who, in the last 4 weeks, had dyspareunia or were sexually inactive due to causes not attributable to their disease. SI was assessed using the Spanish version of female sexual function index questionnaire (FSFI). Results: 56 patients were included. 78.57% presented SI and 19.64% of them were sexually inactive patients due to the disease. Fatigue VAS (β coefficient: -0.08, CI 95%: -0.14 to -0.02; p<0.01), age (β coefficient: -0.23, CI 95%: -0.40 to -0.05; p=0.01) and fibromyalgia (β coefficient: -11.90, CI 95%: -17.98 to -5.82; p<0.01) showed significant and independent association with SI in the multivariate analysis. Conclusions: SI is frequent among women with SSc, and younger patients, without fibromyalgia and with less fatigue have better sexual function.

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Introducción: la disfunción sexual (DS) es común entre las mujeres con enfermedades crónicas, incluyendo esclerosis sistémica (ES). Se ha asociado con características como la duración de la enfermedad, dolor, disminución de la actividad funcional, entre otras. Desde nuestro conocimiento, aún no contamos con datos locales. Objetivos: evaluar la frecuencia de DS en mujeres con ES; describir las características sociodemográficas, clínicas y psicológicas asociadas con la DS en mujeres con ES. Materiales y métodos: estudio observacional, analítico y de corte transversal. Se incluyeron mujeres de entre 20 y 59 años con diagnóstico de ES, según los criterios de clasificación del European League Against Rheumatism/American College of Rheumatology (ACR/EULAR 2013). Se excluyeron pacientes con enfermedades crónicas no controladas, otras patologías reumatológicas autoinmunes, e inactividad sexual o patología genitourinaria no relacionadas a ES en las últimas 4 semanas. La DS se evaluó con la versión en español del cuestionario índice de función sexual femenina (Female sexual function index, FSFI). Resultados: se incluyeron 56 pacientes. El 78,57% presentó DS y 19,64% era sexualmente inactiva debido a la enfermedad. Escala visual análoga (EVA) de fatiga (coeficiente ß: -0,08, IC 95%: -0,14 a -0,02; p<0,01), edad (coeficiente ß: -0,23, IC 95%: -0,40 a -0,05; p=0,01) y fibromialgia (coeficiente ß: -11,90, IC 95%: -17,98 a -5,82; p<0,01) mostraron una asociación significativa e independiente con DS en el análisis multivariado. Conclusiones: la DS es frecuente entre las mujeres con ES, y las pacientes más jóvenes, sin fibromialgia y con menor fatiga presentaron una mejor funcionalidad sexual.

Introduction: sexual impairment (SI) is common among women with chronic diseases, including systemic sclerosis (SSc). It has been associated with characteristics such as the duration of the disease, pain, decreased functional activity, among others. To the best of our knowledge, we still do not have local data. Objectives: to evaluate the frequency of SI in women with SSc. To describe the sociodemographic characteristics, disease itself and psychological items associated with SI in women with SSc. Materials and methods: observational, analytical, cross-sectional study. We included women between 20 and 59 years diagnosed with SSc according to 2013 classification criteria ACR/EULAR. We excluded patients with uncontrolled chronic diseases or other autoimmune rheumatologic diseases and patients who, in the last 4 weeks, had dyspareunia or were sexually inactive due to causes not attributable to their disease. SI was assessed using the Spanish version of female sexual function index questionnaire (FSFI). Results: 56 patients were included. 78.57% presented SI and 19.64% of them were sexually inactive patients due to the disease. Fatigue VAS (ß coefficient: -0.08, CI 95%: -0.14 to -0.02; p<0.01), age (ß coefficient: -0.23, CI 95%: -0.40 to -0.05; p=0.01) and fibromyalgia (ß coefficient: -11.90, CI 95%: -17.98 to -5.82; p<0.01) showed significant and independent association with SI in the multivariate analysis. Conclusions: SI is frequent among women with SSc, and younger patients, without fibromyalgia and with less fatigue have better sexual function.

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Herein, we report an eco-friendly photochemical oxidative Csp2-H thiocyanation and selenocyanation of activated arenes. The reaction proceeds under Violet LED irradiation in the presence of K2S2O8, which quickly oxidizes KSCN and KSeCN, finally producing arylthio/selenocyanates. Using this benign, atom-economic protocol, the desired chalcogenide products were obtained regioselectively, with isolated yields that range from very good to excellent. Although, mechanistic study indicates that it is difficult to distinguish between a radical to a SEAr reaction mechanism between the photo-induced formed •SCN, for the former, or NCSSCN, for the latter, to the aromatic heterocycles. The inhibition experiment together with the observed reactivity and regioselectivity, would be in agreement with the latter. The synthetic methodology designed could be successfully adapted to continuous-flow systems in a segmented-flow regime, employing the organic phase as the product reservoir. Using this setup, the advantage of the latter can be demonstrated by reducing the reaction time and improving the product yields. Similarly, the scaling up of the reaction to gram scale resulted in favorable outcomes by the flow setup, which installs the photo-flow chemistry as a powerful tool to be included into routine reaction procedures, which have great relevance for the pharmaceutical industry.

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Introducción: en la actualidad, el cáncer gástrico sigue ocupando un lugar importante entre las causas de muerte a nivel mundial. Objetivo: determinar las características sociodemográficas, ambientales y clínicas de los pacientes con cáncer gástrico en el municipio de San Gil, Colombia. Metodología: estudio descriptivo transversal. La muestra estuvo conformada por 13 casos de personas con diagnóstico clínico e histopatológico de cáncer gástrico del municipio de San Gil, Santander, residentes del área rural y urbana. El análisis estadístico fue realizado con el programa Statistical Product and Service Solutions, versión 24.0 Resultados: el género con mayor afectación fue el masculino con un 62%. La mediana de edad de los participantes fue de 51 años con una edad mínima de 36 años y una edad máxima de 87 años. En el 61.5% el nivel de escolaridad fue la educación primaria. En cuanto a los factores ambientales, se encontró que el 69.2% consumieron alimentos salados y condimentados. Conclusiones: se encontró que una gran proporción de los participantes fueron del género masculino y residentes del casco urbano. Entre las ocupaciones, las más frecuentes fueron amas de casa y conductores de transporte pesado. Los síntomas que presentaron los participantes en el momento del diagnóstico fueron: pérdida de peso, hematemesis, dolor epigástrico y sensación de plenitud abdominal

Introduction: At present, gastric cancer continues to occupy an important place among the causes of death worldwide. Objective: To determine the sociodemographic, environmental, and clinical characteristics of patients with gastric cancer in the municipality of San Gil, Colombia. Methods: Descriptive cross-sectional study. The sample consisted of 13 cases of people with clinical and histopathological diagnosis of gastric cancer from the municipality of San Gil, Santander, who were residents of rural and urban areas. Statistical analysis was carried out with the program Statistical Product and Service Solutions (SPSS), version 24.0. Results: Men were the most affected, with 61.5%. The median age of the participants was 51 years with a minimum age of 36 years and a maximum of 87 years. In 61.5% the level of education was primary education. Regarding environmental factors, it was found that 69.2% consumed salty and spicy foods. Conclusions: It was found that a large proportion of the participants were male, urban residents. Concerning occupations, the most frequent were housewives and heavy truck drivers. Symptoms that participants presented at the time of diagnosis were weight loss, hematemesis, epigastric pain and fullness in upper abdomen.

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Objetivo: El objetivo de nuestro estudio fue adaptar y validar el Score de Condición de Raynaud (SCR) en pacientes con Esclerosis Sistémica (SSc) que concurren a un hospital público de Argentina. Materiales y Métodos: Para la adaptación, reumatólogos tradujeron al español la versión original en inglés. Para evaluar la validez de constructo se utilizó: Cuestionario de Capacidad Funcional HAQ (HAQ), Índice Duruöz (ID), validados al español para Argentina, Escala Visual Análoga (EVA) de Raynaud por un experto y Score de Rodnan modificado (mRSS). Para evaluar reproducibilidad, se evaluó de forma aleatoria un subgrupo de pacientes sin mediar cambios en el tratamiento ni en la condición clínica 10 días después de la evaluación basal. Resultados: Se incluyeron 35 pacientes con diagnóstico de SSc. La correlación entre SCR y EVA del médico fue de 0.89; SCR y HAQ 0.58; SCR y mRSS 0.61; SCR e ID 0.57 indicando una muy buena correlación principalmente con el EVA del médico y siendo todos estadísticamente significativos. La reproducibilidad fue de 0.998. Conclusiones: Los resultados muestran que el SCR es una herramienta confiable y válida para esta población argentina con SSc.

Objetive: The aim of our study was to adapt and validate the Raynaud's Condition Score (RCS) in patients with Systemic Sclerosis (SSc) who attend a public hospital in Argentina. Materials and Methods: For adaptation, rheumatologists translated to Spanish the original version in English. To assess the construct validity we used: Health Assesment Questionnaire (HAQ), Duruöz´s Hand Index (DHI), spanish validation for Argentina, Raynaud Visual Analogue Scale (VAS) by an expert and Modified Rodnan skin score (mRSS). To assess reproducibility, a subgroup of patients was randomly evaluated with no changes in treatment or clinical condition ten days after the baseline evaluation. Results: A total of 35 patients with SSc were included. The correlation between RCS and Raynaud VAS by an expert was 0.89; RCS and HAQ 0.58; RCS and mRSS 0.61; RCS and DHI 0.57 indicating a very good correlation mainly between the studied Score and the Raynaud VAS and being all statistically significant. The reproducibility was 0.998. Conclusion: The results show that the RCS is a reliable and valid tool for this argentinian population with SSc.

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Benzothiazoles are synthesized from thiobenzanilides using riboflavin as a photosensitizer and potassium peroxydisulfate as a sacrificial oxidizing agent under visible light irradiation. The methodology accepts a broad range of functional groups and affords the 2-substituted benzothiazoles by transition-metal-free organic photoredox catalysis under very mild conditions.

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The reactivity of sulfur- and selenium-centered nucleophiles toward 1-naphthyl radicals was studied in dimethylsulfoxide. The photostimulated reaction of sulfide anions, -SC(NH)C6H5 (1), -SC(NH)NH2 (2), and -SC(NH)CH3 (3), renders, after the addition of MeI, methyl 1-naphthylsulfide as a main product together with bis(1-naphthyl) sulfide and naphthalene under irradiation. Concordantly, the reaction of selenide anions, -SeC(NH)C6H5 (4), -SeC(NH)NH2 (5), and -SeCN (6), produces methyl 1-naphthyl selenide, bis(1-naphthyl) selenide, and naphthalene in the presence of potassium tert-butoxide anion (entrainment conditions). Absolute rate constants for the coupling of ions 1-6 to 1-naphthyl radicals were determined; as a general trend, the selenide-centered nucleophiles enhance in 2 times the reactivity of their sulfide analogues. From the mechanistic study, it is proposed that the unstable radical anion produced by the addition of the nucleophile to 1-naphthyl radical affords, after fragmentation, 1-naphthylsulfide/selenide anion. In addition, experimental results are discussed in terms of density functional theory calculations. There is a generally good agreement between the experimental and the calculated reactivities, the spin density being the main parameter to describe the difference found among the anions under study. Moreover, the calculations predict that anion -SeC(NH)CH3 (7) would be a good candidate for the synthesis of selenide derivatives.

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The photochemical one-electron oxidation of alkyl aryl selenides was studied by means of laser flash photolysis (355 nm). Quenching of the sensitizers in their excited state leads to selenide radical cation in the presence of selenium derivatives. The π-type dimer of methyl phenyl selenide radical cation was detected at 630 nm at expenses of the monomeric radical cation (530 nm). The effect of modification of the aryl and alkyl substituents was also studied, resulting that the formation of dimers depends on both, the electronic properties and steric hindrance of the substituents. Both effects, an increase in steric hindrance in the alkyl moiety or the presence of strongly electron donor groups in the aromatic substituent that stabilizes the radical cation, prevent the dimer formation.

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The mechanism of the Ullmann-type reaction between potassium thioacetate (KSAc) and iodobenzene (PhI) catalyzed by CuI associated with 1,10-phenanthroline (phen) as a ligand was explored experimentally and computationally. The study on C-S bond formation was investigated by UV-visible spectrophotometry, cyclic voltammetry, mass spectrometry, and products assessment from radical probes. The results indicate that under experimental conditions the catalytically active species is [Cu(phen)(SAc)] regardless of the copper source. An examination of the aryl halide activation mechanism using radical probes was undertaken. No evidence of the presence of radical species was found during the reaction process, which is consistent with an oxidative addition cross-coupling pathway. The different reaction pathways leading to the experimentally observed reaction products were studied by DFT calculation. The oxidative addition-reductive elimination mechanism via an unstable CuIII intermediate is energetically more feasible than other possible mechanisms such as single electron transfer, halogen atom transfer, and σ-bond methatesis.

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Photocyclization of N-(thioalkyl)-saccharin was carried out to obtain different polycyclic sultams in good yields. These photoreactions were efficient under inert atmosphere and acetone triplet-sensitized conditions indicating that the triplet excited state is directly involved in the formation of annulated products. The presence of molecular oxygen changes product distribution, and only photo-oxygenation products (sulfoxides and sulfones) were found. This result is especially valuable since, by simple changing from nitrogen- to oxygen-saturated solvent conditions, the reaction outcome can be tuned from cyclized to sulfur oxidation products. Additionally, steady-state photolysis, electrochemistry, and laser time-resolved spectroscopic studies confirmed that these reactions mainly proceeded by intramolecular electron transfer (ET) between the triplet excited saccharin moiety and sulfur atom.

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Photodeprotection of 1,3-dithianes in the presence of thiapyrylium was performed to return to the parent carbonyl compound, and the mechanism was studied by steady state photolysis, laser flash photolysis, and theoretical calculations. Electron transfer from dithianes to triplet sensitizers is extremely fast, and the decay of dithiane radical cations was not affected by the presence of water or oxygen as the consequence of a favorable unimolecular fragmentation pathway. Similar behaviors were observed for dithianes bearing electron-releasing or electron-withdrawing substituents on the aryl moiety, evidenced by C-S bond cleavage to form a distonic radical cation species. The lack of reaction under nitrogen atmosphere, requirement of oxygen for good conversion yields, inhibition of the photodeprotection process by the presence of p-benzoquinone, and absence of a labeled carbonyl final product when the reaction is performed in the presence of H2(18)O all suggest that the superoxide anion drives the deprotection reaction. Density functional theory computational studies on the reactions with water, molecular oxygen, and the superoxide radical anion support the experimental findings.

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2,4-, 2,5-, 2,6- and 3,5-dihydroxyacetophenone (DHA) used as matrices in matrix-assisted ultraviolet laser desorption/ionization mass spectrometry (UV-MALDI-MS) were studied by steady-state and transient absorption spectroscopy, together with DFT calculations at the B3LYP level of theory. All compounds have low fluorescence quantum yields, possibly due to an efficient excited-state intramolecular proton transfer (ESIPT). Laser flash photolysis (LFP) results showed that, only for 2,4-DHA, a phototautomer could be detected at λ = 400 nm. Their photochemical stability in solution at different wavelengths and conditions was analyzed by UV-Vis and (1)H nuclear magnetic resonance spectroscopy ((1)H-NMR), together with thin layer chromatography and ultraviolet laser desorption/ionization mass spectrometry (UV-LDI-MS). Only 3,5-DHA showed decomposition when irradiated, probably because phototautomerization is not possible. Thermal stability studies of these compounds in solid state were also conducted.

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O-Arylation reaction is obtained when N-(2-halophenyl) indolo carboxamides are irradiated in a basic medium. On the basis of photochemical and photophysical experiments, we propose that 2-indolylbenzoxazole is formed by intramolecular electron transfer followed by fast dehalogenation of the halophenyl radical anion pendant moiety, finally a radical-radical collapse renders the observed product.

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