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Oxygen-tolerant, aqueous copper-mediated polymerization approaches are combined with click chemistry in either a sequential or a simultaneous manner, to enable the synthesis of multifunctional protein-polymer conjugates. Propargyl acrylate (PgA) and propargyl methacrylate (PgMA) grafting from a bovine serum albumin (BSA) macroinitiator is thoroughly optimized to synthesize chemically addressable BSA-poly(propargyl acrylate) and BSA-poly(propargyl methacrylate) respectively. The produced multifunctional bioconjugates bear pendant terminal 1-alkynes which can be readily post-functionalized via both [3+2] Huisgen cycloaddition and thiol-yne click chemistry under mild reaction conditions. Simultaneous oxygen-tolerant, aqueous copper-catalyzed polymerization, and click chemistry mediate the in situ multiple chemical tailoring of biomacromolecules in excellent yields.
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Química Clic , Cobre , Cobre/química , Polimerizacion , Polímeros/química , Albúmina Sérica Bovina , Acrilatos , Metacrilatos , Alquinos/química , Azidas/química , Reacción de CicloadiciónRESUMEN
The synthesis of protein-polymer conjugates usually requires extensive and costly deoxygenation procedures, thus limiting their availability and potential applications. In this work, we report the ultrafast synthesis of polymer-protein bioconjugates in the absence of any external deoxygenation via an aqueous copper-mediated methodology. Within 10 min and in the absence of any external stimulus such as light (which may limit the monomer scope and/or disrupt the secondary structure of the protein), a range of hydrophobic and hydrophilic monomers could be successfully grafted from a BSA macroinitiator, yielding well-defined polymer-protein bioconjugates at quantitative yields. Our approach is compatible with a wide range of monomer classes such as (meth) acrylates, styrene, and acrylamides as well as multiple macroinitiators including BSA, BSA nanoparticles, and beta-galactosidase from Aspergillus oryzae. Notably, the synthesis of challenging protein-polymer-polymer triblock copolymers was also demonstrated, thus significantly expanding the scope of our strategy. Importantly, both lower and higher scale polymerizations (from 0.2 to 35 mL) were possible without compromising the overall efficiency and the final yields. This simple methodology paves the way for a plethora of applications in aqueous solutions without the need of external stimuli or tedious deoxygenation.
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Cobre , Polímeros , Acrilamidas/química , Acrilatos/química , Cobre/química , Oxígeno , Polimerizacion , Polímeros/química , Proteínas/química , Estireno/química , Agua/química , beta-GalactosidasaRESUMEN
The development of novel methodologies for the functionalization of saturated heterocycles is highly desirable. Herein, we report a cheap and efficient photochemical method for the C-H functionalization of saturated O-heterocycles, as well as the deconstructive ring-cleavage of S-heterocycles, employing hypervalent iodine alkynylation reagents (ethynylbenziodoxolones, EBX). This photochemical alkynylation is performed utilizing phenylglyoxylic acid as the photoinitiator, leading to the corresponding products in good to high yields, under household fluorescent light bulb irradiation. When O-heterocycles were employed, the expected α-C-H alkynylation took place. In contrast, oxidative ring-opening to form a thioalkyne and an aldehyde was observed with S-heterocycles. Preliminary mechanistic experiments are presented to give first insights into this puzzling divergent reactivity.
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Direct alkylation of C(sp2 )-H bonds to convert an aldehyde into a ketone is a notorious transformation, due to the laborious challenge of the formation of ketyl or acyl radicals. Herein, we report a green, cheap, metal-free and efficient method for the hydroacylation of olefins in water. This photochemical protocol utilizes phenylglyoxylic acid, a commercially available small organic molecule, as the photoinitiator, water as the solvent and household fluorescent lamps as the irradiation source, leading to a broad substrate scope of products in moderate to good yields. A wide range of aromatic and aliphatic aldehydes, terminal and non-terminal alkenes and pharmaceutically relevant molecules can be employed, without the need of directing groups and additives or metal catalysts.
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Photocatalysis is a rapidly evolving area of research in modern organic synthesis. Among the traditional photocatalysts, metal-complexes based on ruthenium or iridium are the most common. Herein, we present the synthesis of two photoactive, ruthenium-based complexes bearing pyridine-quinoline or terpyridine ligands with extended aromatic conjugation. Our complexes were utilized in the atom transfer radical addition (ATRA) of haloalkanes to olefins, using bromoacetonitrile or bromotrichloromethane as the source of the alkyl group. The tailor-made ruthenium-based catalyst bearing the pyridine-quinoline bidentate ligand proved to be the best-performing photocatalyst, among a range of metal complexes and organocatalysts, efficiently catalyzing both reactions. These photocatalytic atom transfer protocols can be expanded into a broad scope of olefins. In both protocols, the photocatalytic reactions led to products in good to excellent isolated yields.
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Alquenos/química , Procesos Fotoquímicos , Acetonitrilos/química , Catálisis , Estructura Molecular , Teoría CuánticaRESUMEN
Selective C-H activation is an area of growing importance. Metal-free C-H activation of branched aldehydes mediating the hydroacylation of electron-deficient alkenes is an attractive transformation, but is limited by selectivity issues, especially in the case of α,α-disubstituted aldehydes. Herein, we report a green, cheap, versatile, and easily reproducible selective hydroacylation of alkenes utilizing phenylglyoxylic acid as the photocatalyst and common household bulbs for irradiation, leading to products in excellent yields and selectivities. The reaction mechanism was also studied to account for the high selectivity.
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Photocatalysis, the use of light to promote organic transformations, is a field of catalysis that has received limited attention despite existing for over 100 years. With the revolution of photoredox catalysis in 2008, the rebirth or awakening of the field of photoorganocatalysis has brought new ideas and reactions to organic synthesis. This review will focus on the sudden outburst of literature regarding the use of small organic molecules as photocatalysts after 2013. In particular, it will focus on acridinium salts, benzophenones, pyrylium salts, thioxanthone derivatives, phenylglyoxylic acid, BODIPYs, flavin derivatives, and classes of organic molecules as catalysts for the photocatalytic generation of C-C and C-X bonds.
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An efficient and green method for the α-hydroxylation of substituted ketones has been developed. This method includes the in situ conversion of various ketones into the corresponding silyl enol ethers and their oxidation to the corresponding α-hydroxy ketones. Two protocols have been established leading either to protected α-hydroxy carbonyls or free α-hydroxy ketones. Both procedures are easy to follow and lead to good to high yields for a variety of ketones.
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INTRODUCTION: Thyroid-associated orbitopathy (TAO) is one of the most common autoimmune inflammatory disorders of the orbit. The presence of anti-thyroid antibodies is believed to play a role in the pathogenesis and clinical status of the TAO patients. Herein, we review the usefulness of TPOAb as a biomarker for TAO. METHODS: A systematic search in MEDLINE library was conducted. Results: Twenty studies were included. TPO is expressed in orbital tissues, and the polymorphism rs11675434 SNP has proven to be associated with clinically evident TAO. Studies in pediatric patients have shown a positive correlation between high TPOAb levels and TAO. In contrast, results in adults are inconsistent. Some studies imply a protective role of TPOAb, yet the majority did not find any association. Some authors have suggested an implication of TPOAb in the pathophysiology of TAO in TRAb-negative patients. CONCLUSIONS: The role of TPOAb in TAO remains unclear and controversial.
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Oftalmopatía de Graves , Humanos , Niño , Oftalmopatía de Graves/diagnóstico , Oftalmopatía de Graves/genéticaRESUMEN
Cardiovascular and related metabolic disorders constitute a worldwide health challenge. Atherosclerosis is a chronic inflammatory condition based on both dyslipidemia and inflammation. Therefore, even when dyslipidemia is controlled, the risk of atherosclerosis remains. Among the most efficient inflammatory mediators used as therapeutic tools in cardiovascular disease are the interleukins, which are pro-inflammatory mediators like cytokines. Moreover, a protein kinase inhibitors, p38 mitogen-activated protein kinase (MAPK) inhibitor, and an inhibitor of a leukocyte adhesion molecule, P-Selectin, have also presented therapeutic potential for this disorder. Colchicine, being an inexpensive therapeutic option, has been proved to be suitable for the prevention of atherosclerosis. In this review, we summarize all the studies, from 2010 to 2020, in which treatment approaches based on the agents mentioned above are evaluated in the management of atherosclerosis.
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The flossing method is an emerging therapeutic intervention based on the use of a floss-band that is circumnavigated at the various points of the body being treated. It is optimally combined with an appropriate exercise program to induce ischemia and release the fascia by applying pressure and movement to functional models. The Pilates method teaches the person to focus on the muscles, especially those responsible for the correct posture. It also helps the individual to become aware of the way he/she breathes. Both methods have positive effects on exercise and rehabilitation. However, medical flossing has not been as well researched as the Pilates method. This study aims to examine the effectiveness of both methods on the strength, endurance, and functionality of healthy individuals. A review of the literature on medical flossing and Pilates was conducted. A systematic research took place from 2014 to 2019. Publications in non-English or non-Greek language were excluded. The articles were retrieved from not only PubMed, Scielo, and Elsevier databases, but also Google Scholar. Both methods are understudied in relation to their effectiveness on the strength, endurance, and functionality of healthy individuals. More studies are required to estimate the effects of both methods on healthy individuals.
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Cushing's syndrome (CS) causes hypogonadotropic hypogonadism and anovulatory infertility due to hypercortisolism, and it is very rare in pregnancy. CS in pregnancy is associated with important maternal-foetal morbidity and mortality, such as preeclampsia and premature delivery. A systematic search was conducted in the MEDLINE library to retrieve articles reporting cases of CS in pregnant women, during the period between 2010 and 2020.Thirty-five reported cases are presented focusing on the ability of diagnosis, treatment therapies, and foetal outcomes. Diagnosis of CS during pregnancy can be challenging and is often delayed, adrenal adenoma being the predominant cause. Both medical treatment and surgery aiming at restoring the cortisol balance reduce maternal and foetal complications.
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Síndrome de Cushing/diagnóstico , Síndrome de Cushing/metabolismo , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/metabolismo , Adulto , Femenino , Humanos , Hidrocortisona/metabolismo , Embarazo , Resultado del EmbarazoRESUMEN
BACKGROUND: Statin intolerance refers to the inability of a patient to tolerate statin therapy, presenting muscle aches, pains, weakness and muscle inflammation. Thus, numerous patients are not treated with suitable statin-based therapy or take only very low doses. As a result, the desired decrease in low-density lipoprotein cholesterol (LDL-C) is not achieved, resulting in patients at a high risk for cardiovascular events, requiring an alternative lipid-lowering treatment. Common treatments manage to reduce the LDL-C level by up to 20%. Recently, new alternative treatment options have been proved to lower the LDL-C level by up to 70%. These treatment strategies are based on human monoclonal antibodies against protein convertase subtilisin/kexin 9 (PCSK9). MATERIALS AND METHODS: Herein, we review the efficiency of anti-PCSK9 in treatment of hypercholesterolemic patients with statin intolerance. We focused on the use of PCSK9 inhibitors in statin-intolerant patients and we estimated the clinical results concerning the reduction of the mean LDL-C concentration and the side effects that were observed. RESULTS: In the majority of cases, treatment strategy based on PCSK9 was successful and achieved the end-points. CONCLUSION: PCSK9 inhibition can be considered as a treatment of option for lipid-lowering in statin-intolerant patients.
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Anticolesterolemiantes , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Anticuerpos Monoclonales Humanizados , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Proproteína Convertasa 9 , SubtilisinaRESUMEN
Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer (BC) and accounts for 10-20% of cases. Due to the lack of expression of several receptors, hormone therapy is largely ineffective for treatment purposes. Nevertheless, TNBC often responds very well to chemotherapy, which constitutes the most often recommended treatment. New beneficial targeted therapies are important to be investigated in order to achieve enhanced outcomes in patients with TNBC. This review will focus on recent therapeutic innovations for TNBC, focusing on various inhibitors such as phosphoinositide 3-kinase (PI3K) pathway inhibitors, poly-ADP-ribosyl polymerase (PARP) inhibitors, aurora kinase inhibitors, histone deacetylase inhibitors (HDACIs), and immune checkpoint inhibitors.
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BACKGROUND/AIM: Inflammatory fibroid polyp (IFP) is a rare, usually solitary and intraluminal polypoid benign tumor that can affect any part of the gastrointestinal (GI) tract, although in the majority of cases it affects the stomach. This lesion is characterized by proliferation of highly vascular fibrous tissue and infiltration by a variable number of different inflammatory cells. Its etiology is unknown. Our aim was to describe all the reported data concerning IFP. MATERIALS AND METHODS: An extensive search of the PubMed Index was performed for publications with titles or abstracts containing the terms: "inflammatory fibroid polyp" with/without "Vanek". Results were filtered for publications in English and concerning only humans. One hundred and twenty-four publications were finally included in this review. RESULTS: IFP has a female predominance. It affects patients in their 5th decade of life, although there are cases of patients from 4 to 84 years of age. IFP usually affects the stomach and more specifically the gastric antrum but can be detected throughout the GI tract. A significant number of cases remain asymptomatic but the most frequent presentations of IFP are abdominal pain, acute abdomen and GI bleeding. Most cases are treated by endoscopic resection of the lesion. No recurrence nor IFP-specific complications have been reported. Histopathology of IFP varies. CONCLUSION: It is relatively safe to conclude that both the etiology and the timing of diagnosis might change the histopathology, immunohistological staining and tissue structure of IFP. Suggested theories should be taken into consideration with caution as the etiology and pathophysiological mechanisms of IFP are unknown.
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Leiomioma , Pólipos , Neoplasias Gástricas , Femenino , Humanos , Leiomioma/diagnóstico , Leiomioma/cirugía , Recurrencia Local de Neoplasia , Pólipos/diagnóstico , Pólipos/cirugía , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirugíaRESUMEN
C-H functionalization at the α-position of heterocycles has become a rapidly growing area of research. Herein, a cheap and efficient photochemical method was developed for the C-H functionalization of heterocycles. Phenylglyoxylic acid (PhCOCOOH) could behave as an alternative to metal-based catalysts and organic dyes and provided a very general and wide array of photochemical C-H alkylation, alkenylation, and alkynylation, as well as C-N bond forming reaction methodologies. This novel, mild, and metal-free protocol was successfully employed in the functionalization of a wide range of C-H bonds, utilizing not only O- or N-heterocycles, but also the less studied S-heterocycles.
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BACKGROUND/AIM: Lipid-lowering drugs have been suggested to affect neurocognitive function. This review aimed to give the latest evidence on the way these agents affect neurocognitive function based on clinical trials. MATERIALS AND METHODS: A systematic search concerning original studies from 2015 to 2020 was performed through the databases PubMed, EMBASE and Cochrane, according to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines. The trials enrolled numerous patients and were conducted in different areas of the world. The terms used are cholesterol, lipid-lowering drugs, statins and cognitive function. RESULTS: Eleven randomized trials met the inclusion criteria. The trials included patients suffering from cardiovascular conditions. In particular, patients with coronary heart disease, coronary heart disease risk equivalents and hypercholesterolemia were tested. The trials included evolocumab, alirocumab, statin, ezetimibe or placebo. CONCLUSION: Lipid-lowering drugs seem to have no significant effect on neurocognitive function, but further research specifically focused on this matter is needed.
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Anticolesterolemiantes , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Hipercolesterolemia , Preparaciones Farmacéuticas , Anticolesterolemiantes/uso terapéutico , Colesterol , HumanosRESUMEN
Metastasis is a process which is characterized by the existence of tumor cells in the bloodstream. This is a necessary situation in order for the malignant cells to be transported to other organs. Thus, the importance of circulating tumor cells (CTCs) in the study of carcinogenesis is widely accepted. These tumor cells are nowadays a topic of intensive research all over the world. CTCs are expressed from tumor cells and the clinical analysis of this expression may help the recognition of a tumor in an earlier stage and also there is an effort to monitor the tumor burden according to these cells. Although a plethora of clinical studies has been conducted, it is still unclear whether the use in clinical aspect will prove to be beneficial in the near future. Few animal models with neoplasia have been studied concerning the circulating tumor cells and it is likely that CTCs may have a predictive, diagnostic or therapeutic value. Herein, the authors review all studies in which human CTCs were transplanted into animals. Therefore, more clinical studies using standardized methods for measuring CTCs are required to elucidate these issues.
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Modelos Animales de Enfermedad , Células Neoplásicas Circulantes/patología , Animales , Humanos , Metástasis de la Neoplasia , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Triple-negative breast cancer (TNBC) is an extremely diverse group of breast tumors, with aggressive clinical behavior, higher rates of distant recurrence and worse overall survival compared to other types of breast cancers. The genetic, transcriptional histological and clinical heterogeneity of this disease has been an obstacle in the progression of targeted therapeutic approaches, as a ubiquitous TNBC marker has not yet been discerned. In terms of that, current studies focus on the classification of TNBC tumors in subgroups with similar characteristics in order to develop a treatment specialized for each group of patients. To date, a series of gene expression profiles analysis in order to identify the different molecular subtypes have been used. Complementary DNA microarrays, PAM50 assays, DNA and RNA sequencing as well as immunohistochemical analysis are some of the methods utilized to classify TNBC tumors. In 2012, the Cancer Genome Atlas (TCGA) Research Network conducted a major analysis of breast cancers using six different platforms, the genomic DNA copy number arrays, DNA methylation, exome sequencing, messenger RNA arrays, microRNA sequencing and reverse-phase protein arrays, in order to assort the tumors in homogenous subgroups. Since then, an increasing number of breast cancer data sets are being examined in an attempt to distinguish the classification with biological interpretation and clinical implementation. In this review, the progress in molecular subtyping of TNBC is discussed, providing a brief insight in novel TNBC biomarkers and therapeutic strategies.
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Neoplasias de la Mama Triple Negativas , Regulación Neoplásica de la Expresión Génica , Humanos , Recurrencia Local de Neoplasia , ARN Mensajero , Transcriptoma , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/terapiaRESUMEN
The hydroacylation of Michael acceptors constitutes a useful tool for the formation of new C-C bonds. In this work, an environmentally friendly procedure was developed, utilizing 4cyanobenzaldehyde as the photoinitiator and household bulbs as the irradiation source. A great variety of substrates was well-tolerated, leading to good yields, and mechanistic experiments were performed to elucidate the catalyst's possible mechanistic pathway. Moreover, the inherent selectivity challenge regarding α,α-disubstituted aldehydes (decarbonylation problem) was studied and addressed.