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Dehydration of alcohols in the presence of copper(II) sulfate has been analyzed computationally. Density functional theory (DFT) calculations on selected alcohols indicate that this reaction can take place via two possible mechanisms: (a) concerted - although asynchronous - type II dyotropic reactions, or (b) stepwise E1-like processes, in which cleavage of the C-O bond occurs in the first step, followed by syn proton elimination. Our calculations show the relationship between the initial alcohol structure and the preferred mechanism, which is a type II dyotropic reaction for primary alcohols, whereas a stepwise process is the favored one when stable carbocation intermediates are energetically accessible. The dehydration of dehydrolinalool (2,7-dimethyl-6-en-1-yn-3-ol, DHL) to yield different alkenes of interest in the fragrance industry is discussed as a case study of its regiochemistry.
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The fragrance compound indomuscone is used here as a scaffold to prepare two different sterically hindered phosphines, one aromatic and another alkylic, in good yields, after four synthetic steps. The new phosphines show enhanced electronic and steric properties when compared to benchmark commercial phosphine ligands, which is reflected in the catalytic results obtained for representative palladium-catalyzed reactions such as the telomerization reaction, the Buchwald-Hartwig and Suzuki cross-coupling reactions of chloroaromatic rings, and the semi-hydrogenation reaction of an alkyne. In particular, the indomuscone-based aromatic phosphine ligand leads to the highest selectivity for the tail-to-head telomerization product between isoprene and methanol, while the indomuscone-based alkylic phosphine ligand shows extraordinary similarities with the Buchwald-type SPhos phosphine ligand.
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The introduction of silicon in biologically-relevant molecules represents an interesting medicinal chemistry tactic. Its use is mainly confined to the fine-tuning of specific molecular properties and organosilicon compounds are underrepresented in typical screening libraries. As part of the European Lead Factory efforts to generate novel, drug discovery-relevant chemical matter, the design and synthesis of 1,1-disubstituted-1-silacycloalkane-based compound libraries is described.
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Desenho de Fármacos , Descoberta de Drogas , Compostos de Organossilício/síntese química , Bibliotecas de Moléculas Pequenas/síntese química , Estrutura MolecularRESUMO
A collaborative study in 10 laboratories was performed to validate an ELISA method developed for the quantitative determination of peanut protein in foods. The ELISA kit used for this study is based on rabbit polyclonal antibody. This kit does not produce any false-positive results or cross-reactivity with a broad range of peanut-free food matrixes. All participants obtained the peanut ELISA kit with standard operational procedures, a list of samples, the samples, and a protocol for recording test results. The study included 15 food samples. Three food matrix samples of zero peanut content showed peanut protein content lower than the first standard (0.10 mg/kg). Three samples with peanut declared as an ingredient revealed peanut protein content outside the calibration curve (absorbance was above the highest standard) in all laboratories, and three samples had the peanut content reported either above the highest standard or within the calibration curve, depending on the laboratory. Six samples with peanut declared as an ingredient gave the peanut protein content within the calibration curve. Only these six samples, together with a positive control sample (CS2), were used for statistical evaluation. The statistical tests (Cochran, Grubbs, and Mandel) and analysis of variance were used for the evaluation of the collaborative study results. Repeatability and reproducibility limits, as well as an LOQ (LOQcollaborative 0.22 mg peanut proteins/kg) and an LOD (LODcollaborative 0.07 mg peanut proteinslkg) for the kit were calculated.
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Arachis/química , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas de Plantas/análise , Kit de Reagentes para Diagnóstico , Comportamento Cooperativo , Limite de DetecçãoRESUMO
The dataset of spectroscopic analysis performed on starting materials, intermediates, and products relating to the synthesis of Hedione are hereby presented. The data were acquired in Durham university during the period between October 2020 and September 2021 for the development of a preparative method to Dehydrohedione. The latter is a key intermediate for the synthesis of cis-Hedione, an important fragrance ingredient. Proton, Carbon-13, and Fluorine-19 Nuclear magnetic resonance of the compounds were recorded employing a Varian 600 MHz, and a Bruker Avance-400 instrument. The IR spectra were recorded in a Perkin Elmer Spectrum Two UATR Two FT-IR and the accurate mass employing a Waters QtoF premier as mass spectrometer.
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BACKGROUND: Component-resolved diagnostics (CRD) has been demonstrated to be an excellent new tool for improving the current diagnosis of allergies, and it allows differentiation between polysensitization and cross-reactivity. OBJECTIVE: To demonstrate the role of cross-reactive pollen allergens in pediatric patients living in areas with large amounts of airborne grass pollen grains who are sensitive to grass pollen and latex. METHODS: Serum samples were obtained from 106 children between 3 and 14 years of age diagnosed with allergies to pollen based on clinical history, skin prick tests, and specific immunoglobulin E (IgE). None of them had allergy symptoms to latex or fruits. From these 106 children, 56 patients revealed positive results to Phleum-specific major allergens but not to cross-reactive allergens. The other 50 patients who showed positive specific IgE to Phleum-specific major allergens and to cross-reactive pollen allergens also showed positive results to latex allergens. CRD was carried out by specific IgE quantification using a fluoro-enzyme immunoassay (ImmunoCAPT System). RESULTS: Results demonstrated a positive significant relationship between the specific IgE to Hev b 8 and Phl p 12 and also between the specific IgE to Hev b 8 and latex extract in the group of patients sensitized to species-specific and cross-reactive Phleum allergens. Positive significant relationships were also found between profilin and avocado or peach sensitizations. No other latex allergens gave positive results. CONCLUSION: The apparent sensitization to latex in pediatric patients allergic to grass pollen is caused by the cross-reactive profilin panallergen; however, it is appears not to be clinically relevant.
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Hipersensibilidade/imunologia , Hipersensibilidade ao Látex/etiologia , Látex/imunologia , Poaceae/imunologia , Pólen/imunologia , Profilinas/imunologia , Adolescente , Alérgenos/imunologia , Antígenos de Plantas/imunologia , Criança , Pré-Escolar , Reações Cruzadas/imunologia , Feminino , Humanos , Hipersensibilidade/etiologia , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Hipersensibilidade ao Látex/imunologia , MasculinoRESUMO
Polycationic oligo(chiral bicyclic guanidines) constitute useful non-peptidic penetrating agents for cell uptake and protein surface recognition. We report herein improved and selective procedures for the preparation of oligoguanidinium scaffolds linked through thioether bonds, with similar or different groups and functions at both ends of the chain. Two synthetic strategies were developed to obtain these compounds in relatively good yields from a common thioacetate precursor: generation of a disulfide intermediate or thiolate formation. Thus, tetraguanidinium intermediates 8 and 22 are best synthesized by the disulfide route, whereas hexamer 29, octamer 31, and trimer 37 arise from a combination of both the disulfide and the thioacetate routes. Finally, tetramer 28 can be readily obtained from either strategy.
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Compostos Bicíclicos com Pontes/química , Compostos Bicíclicos com Pontes/metabolismo , Guanidina/química , Guanidina/metabolismo , Compostos Bicíclicos com Pontes/síntese química , Permeabilidade da Membrana Celular , Técnicas de Química Sintética , Dissulfetos/síntese química , Dissulfetos/química , Guanidina/síntese química , Células HeLa , Humanos , Poliaminas/síntese química , Poliaminas/química , Poliaminas/metabolismo , Polieletrólitos , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/químicaRESUMO
Basic research in sarcoma models has been fundamental in the discovery of scientific milestones leading to a better understanding of the molecular biology of cancer. Yet, clinical research in sarcoma has lagged behind other cancers because of the multiple clinical and pathological entities that characterize sarcomas and their rarity. Sarcomas encompass a very heterogeneous group of tumors with diverse pathological and clinical overlapping characteristics. Molecular testing has been fundamental in the identification and better definition of more specific entities among this vast array of malignancies. A group of sarcomas are distinguished by specific molecular aberrations such as somatic mutations, intergene deletions, gene amplifications, reciprocal translocations, and complex karyotypes. These and other discoveries have led to a better understanding of the growth signals and the molecular pathways involved in the development of these tumors. These findings are leading to treatment strategies currently under intense investigation. Disruption of the growth signals is being targeted with antagonistic antibodies, tyrosine kinase inhibitors, and inhibitors of several downstream molecules in diverse molecular pathways. Preliminary clinical trials, supported by solid basic research and strong preclinical evidence, promises a new era in the clinical management of these broad spectrum of malignant tumors.
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Allergic diseases represent a major global health problem [...].
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There are multiple scales of abstraction from which we can describe the same image, depending on whether we are focusing on fine-grained details or a more global attribute of the image. In brain mapping, learning to automatically parse images to build representations of both small-scale features (e.g., the presence of cells or blood vessels) and global properties of an image (e.g., which brain region the image comes from) is a crucial and open challenge. However, most existing datasets and benchmarks for neuroanatomy consider only a single downstream task at a time. To bridge this gap, we introduce a new dataset, annotations, and multiple downstream tasks that provide diverse ways to readout information about brain structure and architecture from the same image. Our multi-task neuroimaging benchmark (MTNeuro) is built on volumetric, micrometer-resolution X-ray microtomography images spanning a large thalamocortical section of mouse brain, encompassing multiple cortical and subcortical regions. We generated a number of different prediction challenges and evaluated several supervised and self-supervised models for brain-region prediction and pixel-level semantic segmentation of microstructures. Our experiments not only highlight the rich heterogeneity of this dataset, but also provide insights into how self-supervised approaches can be used to learn representations that capture multiple attributes of a single image and perform well on a variety of downstream tasks. Datasets, code, and pre-trained baseline models are provided at: https://mtneuro.github.io/.
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The chain-walking of terminal alkenes (also called migration or isomerization reaction) is currently carried out in industry with unselective and relatively costly processes, to give mixtures of alkenes with significant amounts of oligomerized, branched and reduced by-products. Here, it is shown that part-per-million amounts of a variety of commercially available and in-house made ruthenium compounds, supported or not, transform into an extremely active catalyst for the regioselective migration of terminal alkenes to internal positions, with yields and selectivity up to >99% and without any solvent, ligand, additive or protecting atmosphere required, but only heating at temperatures >150 °C. The resulting internal alkene can be prepared in kilogram quantities, ready to be used in nine different organic reactions without any further treatment.
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Rutênio , Alcenos , CatáliseRESUMO
Prevalence of allergy to fungi is around 3-10%. The most prevalent species involved in sensitizations are Alternaria alternata, Aspergillus fumigatus, Cladosporium herbarum, and Penicillium notatum. Our main objective was to estimate the prevalence of fungal sensitization and its variation across Spain. Following the ICH-GCP, we recruited 1156 patients from 15 allergy departments in Spain. Hospitals were selected by bioclimatic areas. Patients underwent a skin prick test (SPT) with fungi, pollens, house dust mites, and animal dander. Specific IgE to Alternaria alternata and Alt a 1 was assessed in patients with positive SPT to fungi. Of the 233 patients (20.2%) sensitized to at least one of the five fungi tested, 162 (69.5%) were sensitized to Alternaria alternata and Alt a 1, of whom 113 (69.8%) were children; 181 (77.7%) were also polysensitized to other allergens. Alternaria alternata and Alt a 1 sensitization was present in 25.4% of patients in the Continental area, 12.0% in the Mediterranean area, 7.0% in the Semidesertic area, and 2.3% in the Oceanic area. Prevalence of sensitization to the other tested sources was 63.8% to pollens, 60.5% to house dust mite, and 38.1% to animal dander. We concluded that the prevalence of fungal allergy is increasing. Fungi are still the fourth source of allergen sensitization. Alternaria alternata sensitization is the most prevalent in allergic patients to fungi. Alt a 1 is present in almost 90% of the patients sensitized to Alternaria alternata.
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BACKGROUND: Adverse reactions to local anesthetics (LAs), especially esters, are not uncommon, but true allergy is rarely diagnosed. To our knowledge, currently there is no reliable method of determining IgE-mediated hypersensitivity to LAs and cocaine. OBJECTIVE: To assess the clinical value of allergy tests (prick, IgE, challenges, and arrays) in people suffering hypersensitivity reactions (asthma and anaphylaxis) during local anesthesia with cocaine derivatives and drug abusers with allergic symptoms after cocaine inhalation. METHODS: We selected cocaine-dependent patients and allergic patients who suffered severe reactions during local anesthesia from a database of 23,873 patients. The diagnostic yield (sensitivity, specificity, and predictive value) of allergy tests using cocaine and coca leaf extracts in determining cocaine allergy was assessed, taking a positive challenge as the criterion standard. RESULTS: After prick tests, specific IgE, and challenge with cocaine extract, 41 of 211 patients (19.4%) were diagnosed as sensitized to cocaine. Prick tests and IgE to coca leaves (coca tea) had a good sensitivity (95.1% and 92.7%, respectively) and specificity (92.3 and 98.8%, respectively) for the diagnosis of cocaine allergy and LA-derived allergy. CONCLUSIONS: Cocaine may be an important allergen. Drug abusers and patients sensitized to local anesthesia and tobacco are at risk. Both prick tests and specific IgE against coca leaf extract detected sensitization to cocaine. The highest levels were related to severe clinical profiles.
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Alérgenos/imunologia , Anestésicos Locais/imunologia , Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Cocaína/imunologia , Hipersensibilidade a Drogas/diagnóstico , Adolescente , Adulto , Anestésicos Locais/uso terapêutico , Coca , Cocaína/análogos & derivados , Cocaína/uso terapêutico , Estudos Transversais , Feminino , Humanos , Imunização , Imunoglobulina E/metabolismo , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/imunologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Testes Cutâneos , Adulto JovemRESUMO
Resumen En la cavidad oral se pueden presentar lesiones en gíngiva que no están asociadas a placa bacteriana, las cuales requieren de un adecuado diagnóstico y tratamiento. La gingivitis descamativa está usualmente relacionada con desórdenes mucocutáneos, como el pénfigo vulgar (PV), donde las lesiones orales incluyendo las lesiones gingivales, pueden preceder las lesiones cutáneas. El manejo es multidisciplinario y el tratamiento incluye terapia farmacológica tópica y sistémica, se requiere un adecuado control de la placa bacteriana por parte del paciente y una estricta supervisión en el tiempo por parte del profesional para el mantenimiento y estabilidad de los tejidos gingivales. Se presentan dos casos clínicos de pacientes con diagnóstico de PV los cuales fueron manejados de manera oportuna e integral para controlar y estabilizar el factor sistémico y local.
Abstract In the oral cavity, gingiva lesions may occur that are not associated with bacterial plaque, which require adequate diagnosis and treatment. Desquamative gingivitis is usually related to mucocutaneous disorders, such as pemphigus vulgaris (PV), where oral lesions, including gingival lesions, may precede skin lesions. Management is multidisciplinary and treatment includes topical and systemic pharmacological therapy, require adequate control of dental plaque by the patient and strict supervision over time by the professional for the maintenance and stability of the gingival tissues. Two clinical cases of patients with a diagnosis of PV are presented, which were managed in a timely and integral way to control and stabilize the systemic and local factor.
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Humanos , Masculino , Feminino , Adulto , Pênfigo/tratamento farmacológico , Gengivite/tratamento farmacológico , Higiene Bucal , Costa RicaRESUMO
Eye-movements are the only directly observable behavioural signals that are highly correlated with actions at the task level, and proactive of body movements and thus reflect action intentions. Moreover, eye movements are preserved in many movement disorders leading to paralysis (or amputees) from stroke, spinal cord injury, Parkinson's disease, multiple sclerosis, and muscular dystrophy among others. Despite this benefit, eye tracking is not widely used as control interface for robotic interfaces in movement impaired patients due to poor human-robot interfaces. We demonstrate here how combining 3D gaze tracking using our GT3D binocular eye tracker with custom designed 3D head tracking system and calibration method enables continuous 3D end-point control of a robotic arm support system. The users can move their own hand to any location of the workspace by simple looking at the target and winking once. This purely eye tracking based system enables the end-user to retain free head movement and yet achieves high spatial end point accuracy in the order of 6 cm RMSE error in each dimension and standard deviation of 4 cm. 3D calibration is achieved by moving the robot along a 3 dimensional space filling Peano curve while the user is tracking it with their eyes. This results in a fully automated calibration procedure that yields several thousand calibration points versus standard approaches using a dozen points, resulting in beyond state-of-the-art 3D accuracy and precision.
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Movimentos Oculares/fisiologia , Robótica/instrumentação , Robótica/métodos , Tecnologia Assistiva , Adulto , Cabeça/fisiologia , Humanos , Adulto JovemRESUMO
The exploration of innovative chemical space is a critical step in the early phases of drug discovery. Bis-spirocyclic frameworks occur in natural products and other biologically relevant metabolites and show attractive features, such as molecular compactness, structural complexity, and three-dimensional character. A concise approach to the synthesis of bis-spirocyclic-based compound libraries starting from readily available commercial reagents and robust chemical transformations has been developed. A number of novel bis-spirocyclic scaffold examples, as implemented in the European Lead Factory project, is presented.
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Desenho de Fármacos , Compostos Heterocíclicos/síntese química , Compostos Heterocíclicos/farmacologia , Reação de Cicloadição , Ensaios de Triagem em Larga Escala , Indicadores e Reagentes , Modelos Moleculares , Conformação Molecular , Bibliotecas de Moléculas Pequenas , EstereoisomerismoRESUMO
Bee venom hypersensitivity is a clinical entity of outstanding importance because bee stings are a leading cause of mortality worldwide. Individuals with immediate-type bee venom hypersensitivity, beekeepers, and healthy controls were examined for HLA-DRB1, DQB1, and DQA1 alleles by sequence-specific oligonucleotide probe typing. Defined hypersensitivity to bee venom antigen phospholipase A2 (vbPLA2) is significantly associated with the presence of susceptible HLA class II alleles: DRB1*0101 (RR = 2.7, p < 3 x 10(-3)), DRB1*0103 (RR = 21.2, p < 7.5 x 10(-11)), DQA1*0101 (RR = 1.2, p < 38.52 x 10(-10)), and DQB1*0501 (RR = 4, p < 2.18 x 10(-10)). Some HLA class I alleles were also associated with risk to bee venom allergy: A*01 (RR = 2.4, p < 7.5 x 10(-4)), B*57 (RR = 35.1, p < 3.5 x 10(-7)), and B*5901 (p < 3.5 x 10(-5)), but they are probably of secondary significance. Three- (DRB1*0103-DQA1*0101-DQB1*0501) (RR = 21.24, p < 7.5 x 10(-11)) and five-loci (A*01-B*59-DRB1*0103-DQA1*0101-DQB1*0501) (p < 2.3 x 10(-6)) extended haplotypes are also significantly carried by vbPLA2 allergic patients. When HLA allele frequencies from patients are compared with those from beekeepers, only HLA-DRB1*0103 (RR = 11.7, p < 8.5 x 10(-5)) and HLA-DQA1*0101 (p < 0.02) were significantly increased in the former. These observations emphasize the importance of the DRB1*0103-DQA1*0101-DQB1*0501 haplotype as a strong candidate for susceptibility to vbPLA2 hypersensitivity, at least in our region.
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Venenos de Abelha/imunologia , Haplótipos/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe I/genética , Hipersensibilidade Imediata/genética , Fosfolipases A/imunologia , Feminino , Frequência do Gene/genética , Frequência do Gene/imunologia , Genótipo , Antígenos HLA-A/genética , Antígenos HLA-A/imunologia , Antígenos HLA-B/genética , Antígenos HLA-B/imunologia , Antígenos HLA-DQ/genética , Antígenos HLA-DQ/imunologia , Cadeias alfa de HLA-DQ , Cadeias beta de HLA-DQ , Antígenos HLA-DR/genética , Antígenos HLA-DR/imunologia , Cadeias HLA-DRB1 , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Hipersensibilidade Imediata/imunologia , Funções Verossimilhança , Masculino , Fenótipo , Fosfolipases A2 , EspanhaRESUMO
Resumen Los agrandamientos gingivales inducidos por placa bacteriana asociados a factores locales como el uso de aparatología ortodóntica, son frecuentemente observados en pacientes jóvenes, con un inadecuado control del biofilm dental. Dentro de la terapéutica recomendada para tratar dicha condición se encuentra la fase higiénica periodontal y el abordaje quirúrgico. Se presenta un caso clínico de un paciente de 16 años con agrandamiento gingival y su respectivo tratamiento.
Absytract Dental plaque-induced gingival enlargements associated with local factors such as the use of orthodontic appliances are frequently observed in young patients, with inadequate dental biofilm control. Among the recommended therapeutics to treat this condition is the Nonsurgical phase and the surgical approach. A clinical case of a 16-year-old patient with a gingival enlargement and its respective treatment is presented.
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Humanos , Masculino , Adolescente , Gengivectomia/métodos , Gengivite/diagnósticoRESUMO
Liver stereotactic body radiation therapy (SBRT) is an emerging treatment option for oligometastases and may confer a survival benefit in select patients. Herein, we document the first case of liver regeneration (LR) following repeat right hepatic lobe SBRT in a woman with breast cancer metastases. Retraction of the treated lobe was significant with a near 50% volume reduction. Compensatory contralateral lobe hypertrophy was noted with a 320% volume increase. The overall liver volume remained stable, within ±5% of baseline. This case indicates that repeat liver SBRT can be delivered safely to individual patients and that compensatory contralateral lobe hypertrophy is observed to maintain a functional liver volume.
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Transported to the other side: Cyclic D,L-α-peptides self-assemble in lipid bilayers into transmembrane ion channels that may allow efficient transport of glutamic acid. The molecular transport is size/shape selective, as evidenced by the high transport rates observed with cyclodecapeptide-based transmembrane pores but not with the smaller cyclooctapeptide analogue.