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Naturally occurring homoisoflavonoids isolated from some Liliaceae plants have been reported to have diverse biological activities (e.g., antioxidant, anti-inflammatory, and anti-angiogenic effects). The exact mechanism by which homoisoflavonones exert anti-neuroinflammatory effects against activated microglia-induced inflammatory cascades has not been well studied. Here, we aimed to explore the mechanism of homoisoflavonoid SH66 having a potential anti-inflammatory effect in lipopolysaccharide (LPS)-primed BV2 murine microglial cells. Microglia cells were pre-treated with SH66 followed by LPS (100 ng/mL) activation. SH66 treatment attenuated the production of inflammatory mediators, including nitric oxide and proinflammatory cytokines, by down-regulating mitogen-activated protein kinase signaling in LPS-activated microglia. The SH66-mediated inhibition of the nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome complex and the respective inflammatory biomarker-like active interleukin (IL)-1ß were noted to be one of the key pathways of the anti-inflammatory effect. In addition, SH66 increased the neurite length in the N2a neuronal cell and the level of nerve growth factor in the C6 astrocyte cell. Our results demonstrated the anti-neuroinflammatory effect of SH66 against LPS-activated microglia-mediated inflammatory events by down-regulating the NLRP3 inflammasome complex, with respect to its neuroprotective effect. SH66 could be an interesting candidate for further research and development regarding prophylactics and therapeutics for inflammation-mediated neurological complications.
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Antiinflamatorios , Lipopolisacáridos , Microglía , Microglía/efectos de los fármacos , Microglía/metabolismo , Lipopolisacáridos/farmacología , Animales , Ratones , Antiinflamatorios/farmacología , Antiinflamatorios/química , Línea Celular , Isoflavonas/farmacología , Isoflavonas/química , Citocinas/metabolismo , Óxido Nítrico/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Inflamasomas/metabolismoRESUMEN
Dracaeconolide B (1), a naturally occurring homoisoflavane, was isolated from the red resin of Dracaena cochinchinensis. Efforts have been made to elucidate the exact structure of compound 1 since it was confirmed that dracaeconolide B did not contain a 7-hydroxy-5,8-dimethoxy moiety. The structure of dracaeconolide B was revised by synthesis of three homoisoflavanes containing a 5,6,7-trioxygenated moiety each and analysis by NMR spectroscopy. The revised structure of dracaeconolide B was proposed as 3-(4-hydroxybenzyl)-7-hydroxy-5,6-dimethoxychromane. Noyori's Ru-catalyzed asymmetric transfer hydrogenation was used to synthesize (+)-dracaeconolide B. The absolute configuration of the compound was revised to S based on the results obtained by the electronic circular dichroism calculation. We examined the antiangiogenic activity of (S)- and (R)-dracaeconolide B and of synthetic 5,6,7- and 5,7,8-trioxygenated homoisoflavanes. The results can potentially help in the synthesis of related natural products and support drug discovery to treat neovascular eye diseases.
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Dracaena , Dracaena/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/química , Resinas de Plantas/química , EstereoisomerismoRESUMEN
In recent years, a growing number of organic reactions in the literature have shown selectivity controlled by reaction dynamics rather than by transition state theory. Such reactions are difficult to analyse because the transition state theory approach often does not capture the subtlety of the energy landscapes the compounds traverse and, therefore, cannot accurately predict the selectivity. We present an algorithm that can predict the major product and selectivity for a wide range of potential energy surfaces where the product distribution is influenced by reaction dynamics. The method requires as input calculation of the transition states, the intermediate (if present) and the product geometries. The algorithm is quick and simple to run and, except for two reactions with long alkyl chains, calculates selectivity more accurately than transition state theory alone.
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Hypertension and endothelial dysfunction are associated with various cardiovascular diseases. Hydrogen sulphide (H2 S) produced by cystathionine γ-lyase (CSE) promotes vascular relaxation and lowers hypertension. Honokiol (HNK), a natural compound in the Magnolia plant, has been shown to retain multifunctional properties such as anti-oxidative and anti-inflammatory activities. However, a potential role of HNK in regulating CSE and hypertension remains largely unknown. Here, we aimed to demonstrate that HNK co-treatment attenuated the vasoconstriction, hypertension and H2 S reduction caused by angiotensin II (AngII), a well-established inducer of hypertension. We previously found that histone deacetylase 6 (HDAC6) mediates AngII-induced deacetylation of CSE, which facilitates its ubiquitination and proteasomal degradation. Our current results indicated that HNK increased endothelial CSE protein levels by enhancing its stability in a sirtuin-3-independent manner. Notably, HNK could increase CSE acetylation levels by inhibiting HDAC6 catalytic activity, thereby blocking the AngII-induced degradative ubiquitination of CSE. CSE acetylation and ubiquitination occurred mainly on the lysine 73 (K73) residue. Conversely, its mutant (K73R) was resistant to both acetylation and ubiquitination, exhibiting higher protein stability than that of wild-type CSE. Collectively, our findings suggested that HNK treatment protects CSE against HDAC6-mediated degradation and may constitute an alternative for preventing endothelial dysfunction and hypertensive disorders.
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Angiotensina II/toxicidad , Compuestos de Bifenilo/farmacología , Cistationina gamma-Liasa/metabolismo , Células Endoteliales/efectos de los fármacos , Histona Desacetilasa 6/fisiología , Hipertensión/prevención & control , Lignanos/farmacología , Acetilación , Animales , Aorta , Cistationina gamma-Liasa/genética , Células HEK293 , Histona Desacetilasa 6/antagonistas & inhibidores , Histona Desacetilasa 6/genética , Humanos , Sulfuro de Hidrógeno/metabolismo , Hipertensión/inducido químicamente , Hipertensión/enzimología , Hipertensión/fisiopatología , Masculino , Ratones , Ratones Endogámicos C57BL , Complejo de la Endopetidasa Proteasomal/metabolismo , Procesamiento Proteico-Postraduccional , Proteolisis/efectos de los fármacos , Proteínas Recombinantes/metabolismoRESUMEN
A large number of organic reactions feature post-transition-state bifurcations. Selectivities in such reactions are difficult to analyze because they cannot be determined by comparing the energies of competing transition states. Molecular dynamics approaches can provide answers but are computationally very expensive. We present an algorithm that predicts the major products in bifurcating organic reactions with negligible computational cost. The method requires two transition states, two product geometries, and no additional information. The algorithm correctly predicts the major product for about 90% of the organic reactions investigated. For the remaining 10% of the reactions, the algorithm returns a warning indication that the conclusion may be uncertain. The method also reproduces the experimental and the molecular dynamics product ratios within 15% for more than 80% of the reactions. We have successfully applied the method to a trifurcating organic reaction, a carbocation rearrangement, and solvent-dependent Pummerer-like reactions, demonstrating the power of the algorithm to simplify and to help understand highly complex reactions.
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Neovascular eye diseases are a major cause of blindness. Excessive angiogenesis is a feature of several conditions, including wet age-related macular degeneration, proliferative diabetic retinopathy, and retinopathy of prematurity. Development of novel antiangiogenic small molecules for the treatment of neovascular eye disease is essential to provide new therapeutic leads for these diseases. We have previously reported the therapeutic potential of anti-angiogenic homoisoflavanone derivatives with efficacy in retinal and choroidal neovascularization models, although these are racemic compounds due to the C3-stereogenic center in the molecules. This work presents asymmetric synthesis and structural determination of anti-angiogenic homoisoflavanones and pharmacological characterization of the stereoisomers. We describe an enantioselective synthesis of homoisoflavanones by virtue of ruthenium-catalyzed asymmetric transfer hydrogenation accompanying dynamic kinetic resolution, providing a basis for the further development of these compounds into novel experimental therapeutics for neovascular eye diseases.
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Inhibidores de la Angiogénesis/farmacología , Células Endoteliales/efectos de los fármacos , Isoflavonas/farmacología , Neovascularización Fisiológica/efectos de los fármacos , Inhibidores de la Angiogénesis/síntesis química , Inhibidores de la Angiogénesis/química , Proliferación Celular/efectos de los fármacos , Células Endoteliales/metabolismo , Humanos , Hidrogenación , Isoflavonas/síntesis química , Isoflavonas/química , Estructura Molecular , EstereoisomerismoRESUMEN
Honokiol, a biphenolic neolignan isolated from Magnolia officinalis, was reported to have a promising anti-inflammatory activity for the treatment of various diseases. There are many efforts on the synthesis and structure-activity relationship of honokiol derivatives. However, regioselective O-alkylation of honokiol remains a challenge and serves as a tool to provide not only some derivatives but also chemical probes for target identification and mode of action. In this study, we examined the reaction condition for regioselective O-alkylation, in which C2 and C4'-alkylated analogs of honokiol were synthesized and evaluated for inhibitory activity on nitric oxide production and cyclooxygenase-2 expression. Furthermore, we successfully synthesized a potential photoaffinity probe consisting of biotin and benzophenone based on a C4'-alkylated derivative.
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Antiinflamatorios no Esteroideos/farmacología , Compuestos de Bifenilo/farmacología , Inhibidores de la Ciclooxigenasa 2/farmacología , Inflamación/tratamiento farmacológico , Lignanos/farmacología , Alquilación , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/química , Ciclooxigenasa 2/metabolismo , Inhibidores de la Ciclooxigenasa 2/síntesis química , Inhibidores de la Ciclooxigenasa 2/química , Humanos , Inflamación/metabolismo , Lignanos/síntesis química , Lignanos/química , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Ratones , Estructura Molecular , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Células RAW 264.7 , EstereoisomerismoRESUMEN
Modern supramolecular chemistry is overwhelmingly based on non-covalent interactions involving organic architectures. However, the question of what happens when you depart from this area to the supramolecular chemistry of structures based on non-carbon frameworks remains largely unanswered, and is an area that potentially provides new directions in molecular activation, host-guest chemistry, and biomimetic chemistry. In this work, we explore the unusual host-guest chemistry of the pentameric macrocycle [{P(µ-Nt Bu}2 NH]5 with a range of anionic and neutral guests. The polar coordination site of this host promotes new modes of guest encapsulation via hydrogen bonding with the πâ systems of the unsaturated C≡C and C≡N bonds of acetylenes and nitriles as well as with the PCO- anion. Halide guests can be kinetically locked within the structure by oxidation of the phosphorus periphery by oxidation to PV . Our study underscores the future promise of p-block macrocyclic chemistry.
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Deformation twinning provides a mechanism for energy dissipation in crystalline structures, with important implications on the mechanical response of carbonate biogenic materials. Carbonate crystals can incorporate magnesium, e.g. in the sea, modifying their elastic response significantly. We present a full atom computational investigation of the dependence of the twinning response of calcite with magnesium content, covering compositions compatible with three main structures, calcite, dolomite and magnesite. We find, in agreement with experiments that the incorporation of magnesium disfavors twinning as a dissipation mechanism in ordered structures (dolomite, magnesite), however the response is strongly dependent on the arrangement of the magnesium ions in the crystal structure. We show that structures with a high content of magnesium (>33%) in a disordered arrangement, lead to plastic response before twinning or fracturing. We demonstrate that the position of the magnesium ions plays a key role in the determination of the crystal deformation mode. This observation is correlated with the formation of percolation clusters of magnesium in magnesian calcites.
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Percutaneous drug delivery using microneedles (MNs) has been extensively exploited to increase the transdermal permeability of therapeutic drugs. However, it is difficult to control the precise dosage with existing MNs and they need to be attached for a long time, so a more simple and scalable method is required for accurate transdermal drug delivery. In this study, we developed grooved MNs that can be embedded into the skin by mechanical fracture following simple shear actuation. Grooved MNs are prepared from hyaluronic acid (HA), which is a highly biocompatible and biodegradable biopolymer. By adjusting the aspect ratio (length:diameter) of the MN and the position of the groove, the MN tip inserted into the skin can be easily broken by shear force. In addition, it was demonstrated that it is possible to deliver the desired amount of triamcinolone acetonide (TCA) for alopecia areata by controlling the position of the groove structure and the concentration of TCA loaded in the MN. It was also confirmed that the tip of the TCA MN can be accurately delivered into the skin with a high probability (98% or more) by fabricating an easy-to-operate applicator to provide adequate shear force. The grooved MN platform has proven to be able to load the desired amount of a drug and deliver it at the correct dose.
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Dry age-related macular degeneration (AMD) is a type of disease that causes visual impairment due to changes in the macula located in the center of the retina. The accumulation of drusen under the retina is also a characteristic of dry AMD. In this study, we identified a compound (JS-017) that can potentially degrade N-retinylidene-N-retinylethanolamine (A2E), one of the components of lipofuscin, using fluorescence-based screening, which measures A2E degradation in human retinal pigment epithelial cells. JS-017 effectively degraded A2E in ARPE-19 cells and consequently suppressed the activation of the NF-κB signaling pathway and expression of inflammatory and apoptosis genes induced by blue light (BL). Mechanistically, JS-017 induced LC3-II formation and improved autophagic flux in ARPE-19 cells. Additionally, the A2E degradation activity of JS-017 was found to be decreased in autophagy-related 5 protein-depleted ARPE-19 cells, suggesting that autophagy was required for A2E degradation mediated by JS-017. Finally, JS-017 exhibited an improvement in BL-induced retinal damage measured through fundus examination in an in vivo retinal degeneration mouse model. The thickness of the outer nuclear layer and inner/external segments, which was decreased upon exposure to BL irradiation, was also restored upon JS-017 treatment. Altogether, we demonstrated that JS-017 protected human retinal pigment epithelium (RPE) cells from A2E and BL-induced damage by degrading A2E via the activation of autophagy. The results suggest the feasibility of a novel A2E-degrading small molecule as a therapeutic agent for retinal degenerative diseases.
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Luz , Retina , Humanos , Ratones , Animales , Epitelio Pigmentado de la Retina/metabolismo , Epitelio Pigmentado de la Retina/efectos de la radiación , Línea Celular , Autofagia/fisiologíaRESUMEN
The use of machine learning techniques in computational chemistry has gained significant momentum since large molecular databases are now readily available. Predictions of molecular properties using machine learning have advantages over the traditional quantum mechanics calculations because they can be cheaper computationally without losing the accuracy. We present a new extrapolatable and explainable molecular representation based on bonds, angles and dihedrals that can be used to train machine learning models. The trained models can accurately predict the electronic energy and the free energy of small organic molecules with atom types C, H N and O, with a mean absolute error of 1.2 kcal mol-1. The models can be extrapolated to larger organic molecules with an average error of less than 3.7 kcal mol-1 for 10 or fewer heavy atoms, which represent a chemical space two orders of magnitude larger. The rapid energy predictions of multiple molecules, up to 7 times faster than previous ML models of similar accuracy, has been achieved by sampling geometries around the potential energy surface minima. Therefore, the input geometries do not have to be located precisely on the minima and we show that accurate density functional theory energy predictions can be made from force-field optimised geometries with a mean absolute error 2.5 kcal mol-1.
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OBJECTIVE: To introduce our novel technique for myometrial defect closure after adenomyomectomy. MATERIALS AND METHODS: A retrospective cohort study. A total of 40 patients with adenomyosis who visited our clinic between October 2012 and January 2018 were recruited. Of those 34 patients were eligible for analysis. RESULTS: The mean thickness of the affected uterine wall before surgery was 4.02 cm ± 1.11, dropping to 2.37 cm ± 0.84 postoperatively. This led to a mean drop of 41% in the thickness of the affected wall, which was found to be significant using a paired t-test (p < 0.0001). The mean preoperative pain score was 8.68 ± 1.12, while the postoperative mean was 0.06 ± 0.34. The mean preoperative CA 125 was 121.73 ± 117.29, dropping to 6.95 ± 2.60 postoperatively. This was found to be significantly lower using both the Wilcoxon Signed Rank and Sign tests (p = 0.0156). CONCLUSION: Myometrial defect closure in a layer-by-layer fashion after robot-assisted laparoscopic adenomyomectomy is a reproducible technique. This uterine conserving method was effective in reducing our patients' pain. It may be the solution to maintaining adequate myometrial wall thickness, uterine layer alignment, and endometrial integrity.
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Adenomiosis/cirugía , Procedimientos Quirúrgicos Ginecológicos/métodos , Laparoscopía/métodos , Dolor Pélvico/diagnóstico por imagen , Robótica , Miomectomía Uterina/métodos , Adenomiosis/patología , Adulto , Femenino , Procedimientos Quirúrgicos Ginecológicos/efectos adversos , Humanos , Laparoscopía/efectos adversos , Persona de Mediana Edad , Miometrio , Dolor , Dolor Pélvico/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Miomectomía Uterina/efectos adversosRESUMEN
Activity of the heme synthesis enzyme ferrochelatase (FECH) is implicated in multiple diseases. In particular, it is a mediator of neovascularization in the eye and thus an appealing therapeutic target for preventing blindness. However, no drug-like direct FECH inhibitors are known. Here, we set out to identify small-molecule inhibitors of FECH as potential therapeutic leads using a high-throughput screening approach to identify potent inhibitors of FECH activity. A structure-activity relationship study of a class of triazolopyrimidinone hits yielded drug-like FECH inhibitors. These compounds inhibit FECH in cells, bind the active site in cocrystal structures, and are antiangiogenic in multiple in vitro assays. One of these promising compounds was antiangiogenic in vivo in a mouse model of choroidal neovascularization. This foundational work may be the basis for new therapeutic agents to combat not only ocular neovascularization but also other diseases characterized by FECH activity.
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Inhibidores de la Angiogénesis , Ferroquelatasa , Inhibidores de la Angiogénesis/farmacología , Animales , Ferroquelatasa/química , Ferroquelatasa/metabolismo , Ratones , Neovascularización PatológicaRESUMEN
Ovarian cancer (OC) is the most lethal gynecologic malignancy and in-time diagnosis is limited because of the absence of effective biomarkers. Germline BRCA1/2 genetic alterations are risk factors for hereditary OC; risk-reducing salpingo-oophorectomy (RRSO) is pursued for disease prevention. However, not all healthy carriers develop the disease. Therefore, identifying predictive markers in the BRCA1/2 carrier population could help improve the identification of candidates for preventive RRSO. In this study, plasma samples from 20 OC patients (10 patients with BRCA1/2 wild type (wt) and 10 with the BRCA1/2 variant (var)) and 20 normal subjects (10 subjects with BRCA1/2wt and 10 with BRCA1/2var) were analyzed for potential biomarkers of hereditary OC. We applied a bottom-up proteomics approach, using nano-flow LC-MS to analyze depleted plasma proteome quantitatively, and potential plasma protein markers specific to the BRCA1/2 variant were identified from a comparative statistical analysis of the four groups. We obtained 1505 protein candidates from the 40 subjects, and SPARC and THBS1 were verified by enzyme-linked immunosorbent assay. Plasma SPARC and THBS1 concentrations in healthy BRCA1/2 carriers were found to be lower than in OC patients with BRCA1/2var. If plasma SPARC concentrations increase over 337.35 ng/mL or plasma THBS1 concentrations increase over 65.28 µg/mL in a healthy BRCA1/2 carrier, oophorectomy may be suggested.
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OBJECTIVE: Familial cancer appears at a young age and its incidence is increasing. About 12% of familial ovarian cancer cases are associated with BRCA1/2 mutations (BRCAm). In this study, we investigated BRCA1 methylation may predict ovarian cancer in those with a family history of cancer (FHC) but without BRCA1/2 mutations (BRCAwt). METHODS: Using peripheral blood DNA from 55 subjects without a history of cancer [cancer(-)] and 52 ovarian cancer patients, we examined BRCA1 promoter methylation through bisulfite sequencing of the promoter and expressed the results as the cumulative methylation index. Then, we evaluated the BRCA1 promoter methylation according to BRCA1/2 germline mutations. RESULTS: BRCA1 methylation was more prevalent in the BRCAm cancer(-) group than in the BRCAwt cancer(-) group and ovarian cancer patients (p=0.031 and p=0.019, respectively). In the BRCAwt cancer(-) group, BRCA1 methylation was more prevalent in those with an FHC than in those without one and in the BRCAm cancer(-) group with an FHC (p=0.001 and p<0.001, respectively). CONCLUSION: Our data suggest a predictive role of BRCA1 methylation profile for ovarian cancer in those without a history of cancer but with an FHC. BRCA1 methylation has important implications for diagnostic and predictive testing of those with BRCAwt cancer(-) status with FHC.
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Proteína BRCA1 , Neoplasias Ováricas , Proteína BRCA1/genética , Proteína BRCA2/genética , Carcinoma Epitelial de Ovario , Femenino , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Metilación , Neoplasias Ováricas/genéticaRESUMEN
BACKGROUND: Exosomal miRNAs regulate gene expression and play important roles in several diseases. We used exosomal miRNA profiling to investigate diagnostic biomarkers of epithelial ovarian cancer (EOC). METHODS: In total, 55 individuals were enrolled, comprising healthy (n = 21) and EOC subjects (n = 34). Small mRNA (smRNA) sequencing and real-time PCR (RT-PCR) were performed to identify potential biomarkers. Receiver operating characteristic (ROC) curves were conducted to determine biomarker sensitivity and specificity. RESULTS: Using smRNA sequencing, we identified seven up-regulated (miR-4732-5p, miR-877-5p, miR-574-3p, let-7a-5p, let-7b-5p, let-7c-5p, and let-7f-5p) and two down-regulated miRNAs (miR-1273f and miR-342-3p) in EOC patients when compared with healthy subjects. Of these, miR-4732-5p and miR-1273f were the most up-regulated and down-regulated respectively, therefore they were selected for RT-PCR analysis. Plasma derived exosomal miR-4732-5p had an area under the ROC curve of 0.889, with 85.7% sensitivity and 82.4% specificity in distinguishing EOC patients from healthy subjects (p<0.0001) and could be a potential biomarker for monitoring the EOC progression from early stage to late stage (p = 0.018). CONCLUSIONS: Plasma derived exosomal miR-4732-5p may be a promising candidate biomarker for diagnosing EOC.
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Biomarcadores de Tumor/metabolismo , Carcinoma Epitelial de Ovario/diagnóstico , Carcinoma Epitelial de Ovario/genética , Exosomas/metabolismo , MicroARNs/metabolismo , Adulto , Anciano , Femenino , Humanos , Persona de Mediana EdadRESUMEN
Coordination of Cu(i) or Pd(ii) to seleno-cyclodiphosph(v)azanes of the type [RNH(Se)P(µ-NtBu)]2 results in positively charged anion receptor units which have increased anion affinity over the neutral seleno-phosph(v)azanes, due to the increase in electrostatic interactions between the receptor and the guest anions. The same effect is produced by replacement of one of the P[double bond, length as m-dash]Se units by a P-Me+ unit.
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Homoisoflavonoids are in the subclass of the larger family of flavonoids but have one more alkyl carbon than flavonoids. Among them, 5,7,8-trioxygenated homoisoflavonoids have not been extensively studied for synthesis and biological evaluation. Our current objective is to synthesize 2 5,7,8-trioxygenated chroman-4-ones and 12 5,7,8-trioxygenated homoisoflavonoids that have been isolated from the plants Bellevalia eigii, Drimiopsis maculata, Ledebouria graminifolia, Eucomis autumnalis, Eucomis punctata, Eucomis pallidiflora, Chionodoxa luciliae, Muscari comosum, and Dracaena cochinchinensis. For this purpose, 1,3,4,5-tetramethoxybenzene and 4'-benzyloxy-2',3'-dimethoxy-6'-hydroxyacetophenone were used as starting materials. Asymmetric transfer hydrogenation using Noyori's Ru catalyst provided 5,7,8-trioxygenated-3-benzylchroman-4-ones with R-configuration in high yield and enantiomeric excess. By selective deprotection of homoisoflavonoids using BCl3, the total synthesis of natural products including 10 first syntheses and three asymmetric syntheses has been completed, and three isomers of the reported dracaeconolide B could be provided. Our research on 5,7,8-trioxygenated homoisoflavonoids would be useful for the synthesis of related natural products and pharmacological applications.
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Colposcopy is widely used to detect cervical cancers, but experienced physicians who are needed for an accurate diagnosis are lacking in developing countries. Artificial intelligence (AI) has been recently used in computer-aided diagnosis showing remarkable promise. In this study, we developed and validated deep learning models to automatically classify cervical neoplasms on colposcopic photographs. Pre-trained convolutional neural networks were fine-tuned for two grading systems: the cervical intraepithelial neoplasia (CIN) system and the lower anogenital squamous terminology (LAST) system. The multi-class classification accuracies of the networks for the CIN system in the test dataset were 48.6 ± 1.3% by Inception-Resnet-v2 and 51.7 ± 5.2% by Resnet-152. The accuracies for the LAST system were 71.8 ± 1.8% and 74.7 ± 1.8%, respectively. The area under the curve (AUC) for discriminating high-risk lesions from low-risk lesions by Resnet-152 was 0.781 ± 0.020 for the CIN system and 0.708 ± 0.024 for the LAST system. The lesions requiring biopsy were also detected efficiently (AUC, 0.947 ± 0.030 by Resnet-152), and presented meaningfully on attention maps. These results may indicate the potential of the application of AI for automated reading of colposcopic photographs.