Electrifying sulfur: Single crystals of tetrathiotetracene (TTT) and hexathiapentacene (HTP) were synthesized using a zone‐melting chemical‐vapor‐transport method. When applied as organic battery electrodes, HTP shows a superior performance, which is linked to different S–S bonding scenarios compared with TTT. The number of adjacent sulfur atoms affects the character of the S–S bonds, which is critical for the design of novel organic battery materials. Abstract The molecular design of organic...
Spic and span! A facile and scalable chemical vapor deposition approach was developed to synthesize meter‐sized samples of superclean graphene with an average cleanness of 99 %. The weak oxidizing ability of CO2 was essential to selectively etch away the intrinsic contamination, amorphous carbon, on the graphene surface. Abstract Contamination commonly observed on the graphene surface is detrimental to its excellent properties and strongly hinders its application. It is still a great challenge...
Incorporation of the CF3 group into arenes has found increasing importance in drug discovery. Here we report the first photoredox‐catalyzed cross‐coupling of aryl thianthrenium salts with a copper‐based trifluoromethyl reagent, which enables a site‐selective late‐stage trifluoromethylation of arenes. The reaction proceeds with broad functional group tolerance, even for complex small molecules on gram scale. The method was further extended to produce pentafluoroethylated derivatives.
A chiral composite material, derived from the deposition of a chiral nickel‐diamine complex via wet impregnation to MCM‐41, was shown to be an efficient heterogeneous catalyst for asymmetric 1,4‐addition reactions of 1,3‐dicarbonyl compounds with nitroalkenes, and of nitromethane with alkylidenemalonates. It was discovered that MCM‐41 enhanced the reactivity and improved the stability of the chiral nickel complex that resides within the mesoporous material.
A protocol for the three‐component 1,4‐carboamination of dienes is described. Synthetically versatile Weinreb amides were coupled with 1,3‐dienes and readily available dioxazolones as the nitrogen source using [Cp*RhCl2]2‐catalyzed C–H activation to deliver the 1,4‐carboaminated products. This transformation proceeds under mild reaction conditions and affords the products with high levels of regio‐ and E‐selectivity. Mechanistic investigations suggest an inter‐mediate RhIII–allyl species is trapped...
Carbon decorated with multiple active sites from heteroatom doping and the amorphous state is presented. The multiple active sites could reversibly bond with sodium ions during the charge–discharge processes, achieving fast and long‐life sodium storage properties. Abstract Although sodium ion batteries (SIBs) possess many beneficial features, their rate performance, cycling stability, and safety need improvement for commercial applications. Based on the mechanisms of the sodium ions storage...
Chiral octahedral complexes were prepared from earth‐abundant cobalt and chiral N4 ligands. One structurally well‐defined cobalt complex was an efficient chiral catalyst in visible‐light‐induced radical conjugated additions. By doing so, synthetically valued chiral ketones and 1,4‐dicarbonyls were afforded in 47–>99 % yields (46 examples) with up to 97:3 e.r. Abstract Chiral catalysts tolerating photochemical reactions are in great demand for the vast development of visible‐light‐induced...
Gold, basically: The structure of the basic [Au25(SCH2CH2Py)18]− cluster determined by X‐ray crystallography is similar to that known for the phenyl ethanethiolate analogue, but with pyridyl‐N coordination to Na+, a more relaxed ligand shell, and a profoundly layered arrangement in solid state. Abstract The synthesis of high‐purity and high‐yield Au25 clusters protected by the basic pyridyl ethanethiol (HSCH2CH2Py, 4‐PyET and 2‐PyET) is presented. Single‐crystal X‐ray diffraction of the [Au25(4‐PyET)18]−⋅Na+...
No protection needed: The first enantioselective total syntheses of pallambins A–D were achieved without the use of protecting groups. A salient feature of these syntheses is the formation of three rings in three cyclizations. A palladium‐catalyzed process for the dehydrobromination of α‐bromoketones was also developed. Abstract The first enantioselective total syntheses of (−)‐pallambins A–D have been achieved in 15 or 16 steps from a known chiral cyclohexenone. Salient features of the syntheses...
Five in one go! A novel domino reaction for the highly stereoselective synthesis of pentasubstituted tetrahydropyrans is reported. Based on a twofold addition of enamides to aldehydes, three new σ‐bonds and five continuous stereogenic centers are formed in this one‐pot process with a remarkable degree of diastereoselectivity. In most cases, the formation of one out 16 diastereomers is observed. Abstract A novel method for the highly stereoselective synthesis of tetrahydropyrans is reported....
A virtuous circle: Rain‐like precipitation, formed in a microfluidic implementation of the water cycle, creates local salt fluctuations at the gas–water interface, which separates DNA or RNA strands below their melting temperature. This salt‐dependent strand separation could have facilitated DNA or RNA replication on the early Earth. Abstract To understand the emergence of life, a better understanding of the physical chemistry of primordial non‐equilibrium conditions is essential. Significant...
Fine‐tuning energy levels: A three‐dimensional porous fluorographdiyne network on carbon cloth serves as an active metal‐free catalyst for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), as well as overall water splitting (OWS) under acidic as well as alkaline conditions. The strong F−C bonding modifies the local p–p coupling, which affects the filling of the electronic orbitals. Abstract A highly efficient bifunctional metal‐free catalyst was prepared by growth of...
5aTHQs are small, lipophilic metabolites produced by Streptomyces nigrescens HEK616 in the combined culture. They form membrane‐active aggregates by which biological activity can be regulated. Abstract Organisms often produce secondary metabolites as a mixture of biosynthetically related congeners. However, why are metabolites with minor chemical variations produced simultaneously? 5‐Alkyl‐1,2,3,4‐tetrahydroquinolines (5aTHQs) are small, lipophilic metabolites produced by Streptomyces nigrescens...
Bowl inversion: A series of exo‐type buckybowl‐supramolecules are obtained using a concave nanographene acceptor. The reversible bowl inversion in the solid state is realized in the complex with weakest binding strength by heating and cooling cycles and unambiguously observed by single‐crystal X‐ray diffraction. Abstract Bowl inversion is a unique property of buckybowls. The polarity and assembly configuration of buckybowls are reversed after bowl inversion. So far, this unique phenomenon has...
Sharing is caring: By investigating the fate of a previously undetectable Brønsted acid proton, the protecting‐group ability of TiO2 was discovered. This new surface‐chemistry concept has been captured by modeling HCOOH on top of anatase TiO2(101) facets. The acid proton is shared between adsorbate and surface and forms a short strong hydrogen bond. Abstract Carboxylic‐acid adsorption on anatase TiO2 is a relevant process in many technological applications. Yet, despite several decades of investigations,...
Alkene‐reducing bugs: The microorganism Escherichia coli BL21(DE3) was found to reduce a range of keto‐acrylic alkene substrates without the need for genetic modification. The biocompatibility of the reaction was examined in a cellular setting and used to inform the metal‐free synthesis of aminolevulinic acid from a lignin‐derived substrate. Abstract Microorganisms can be programmed to perform chemical synthesis via metabolic engineering. However, despite an increasing interest in the use of...
Chiral Conflict as a Method to Create Stimuli‐Responsive Materials Based on Dynamic Helical Polymers
Conflict detecting: The chiral conflict effect in chiral helical copolymers becomes an instrument for the development of multi‐sensor materials. Its potential for identifying monovalent and divalent metal ions is demonstrated. Abstract A new multi‐sensor material based on helical copolymers showing the chiral conflict effect have been prepared. It can successfully detect and identify diverse metal cations in solution. The design of this material has taken into account not only the opposite...
Highly fluorinated glory: The recently developed TCICA/KF approach to oxidative polyfluorination was used to prepare and structurally characterize a series of aryl‐TeF5 compounds as well as aryl‐TeF4CF3 compounds. Reactivity studies indicate that the TeF5 group is more stable than previously thought. Abstract The TeF5 group is significantly underexplored as a highly fluorinated substituent on an organic framework, despite it being a larger congener of the acclaimed SF5 group. In fact, only...
Using optimal combinations of salts and ligands, zeolitic imidazolate framework composite structures with ferrimagnetic behavior can be readily obtained by a one‐step synthesis. The ferrimagnetism of the composite originates from binary oxides of iron and transition metals. This approach shows similarities to the natural mineralization of iron oxide species, as is observed in ores and in biomineralization. Abstract Metal–organic frameworks (MOFs) capable of mobility and manipulation are attractive...
An enantioselective sulfenylation/semipinacol rearrangement of 1,1‐disubstituted and trisubstituted allylic alcohols was accomplished by chiral Lewis base/chiral Brønsted acid cocatalysis. Various β‐arylthio ketones bearing all‐carbon quaternary centers were generated in moderate to excellent yields and excellent enantioselectivities. Abstract An enantioselective sulfenylation/semipinacol rearrangement of 1,1‐disubstituted and trisubstituted allylic alcohols was accomplished with a chiral Lewis...
A single‐site catalyst is fabricated by assembly of metal–porphyrin molecules, which enables the precise identification of the active sites for d‐orbital energy engineering. The activity of as‐assembled products for CO2 electroreduction is significantly promoted by elevating the energy level of metal d orbitals, exhibiting a remarkable Faradaic efficiency of 96 %. Abstract The single‐site catalyst (SSC) characteristic of atomically dispersed active centers will not only maximize the catalytic...
Transition metals‐carbon (CTM) composites show ample activity in many catalytic reactions. However, a synthesis which allows control over their final composition, distribution and properties is still considered as a great challenge. Here, we report a new, straightforward path for the synthesis of transition‐metal nanoparticles engulfed in crystalline carbon with excellent control over the metals composition, amount, ratio and catalytic properties. The new approach consists in using molten monomers...
Tuning morphologies of self‐assembled structures in water is a major challenge. Here we present a salen‐based amphiphile which, using complexation with distinct transition metal ions, allows to control effectively the self‐assembly morphology in water, as observed by Cryo‐TEM and confirmed by DLS measurements. Applying this strategy with various metal ions gives a broad spectrum of self‐assembled structures starting from the same amphiphilic ligand (from cubic structures to vesicles and micelles)....
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Abstract Purpose of Review Parkinson’s disease (PD) has a wide spectrum of symptoms including the presence of psychiatric disease. At present, most treatment plans, comprised of dopaminergic drugs, are chronic and complex. Though dopaminergic agents are quite efficient in managing the motor aspects of the disease, chronic pharmacotherapy specifically with dopamine receptor agonists has been highly linked to the occurrence of Impulse...
Abstract Purpose of Review Giant cell arteritis is a systemic large vessel vasculitis that affects the older population and can cause progressive and at times, devastating complications including vision loss. While this has been commonly diagnosed and treated among vasculitides, the treatment options are limited and can have long-term adverse effects. The purpose of our review on GCA is to identify and discuss the pathophysiology...
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Abstract Diabetes mellitus is a chronic disease that is increasing at an alarming rate all over the world. The aim of this study was to assess the quality information available on YouTube on diabetes and oral healthcare. This cross-sectional study made a search in YouTube (https://www.youtube.com/). Two reviewers assessed the videos and categorized them into useful, misleading or personal experience, and scored them using a global quality scale (GQS) from 1 to 5 according to their...
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The homeodomain-leucine zipper (HD-Zip) gene family, a group of plant-specific transcriptional factors (TFs), participates in regulating growth, development, and environmental responses. However, the characteristics and biological functions of HD-Zip genes in Prunus mume, which blooms in late winter or early spring, have not been reported. In this study, 32 HD-Zip genes, named PmHB1–PmHB32 based on their chromosomal positions, were identified in the genome of P. mume. These genes are distributed...
Background High primary productivity in the midst of high toxicity defines hydrocarbon seeps; this feature usually results in significantly higher biomass, but in lower diversity communities at seeps rather than in the surrounding non-seep benthos. Qualitative estimates indicate that this dichotomy does not necessarily hold true in high latitude regions with respect to megafauna. Instead, high latitude seeps appear to function as local hotspots of both megafaunal diversity and abundance,...
Background Cellular therapy clinical applications require large-scale production of stem cells. Therefore, abundance, ease of isolation, and proliferative potential are the most important factors in choosing the appropriate source of cells for transplantation studies. Multipotent stem cells obtained from periodontal ligament (PDL) can be used in periodontal tissue regeneration. In this study, we aimed to evaluate and compare the characteristics of periodontal ligament stem cells...
We describe a new species of Epictia based on eight specimens from Nicaragua collected and housed in the collection of the Natural History Museum Vienna for more than a century. The species differs from the congeners by the combination of external morphological characters: midtail scale rows 10; supralabials two, anterior one large and in broad contact with supraocular; infralabials four; subcaudals 14–19; middorsal scale rows 250–267; supraocular scales present; frontal scale distinct; striped dorsal...
Background Motor competence (MC) is generally used to describe a person’s proficiency in a variety of motor skills and is the basis for one’s performance in sports and recreational activities. Functional Movement Screen (FMSTM) is one of the most used screening systems to provide interpretable measure of movement quality. Both FMSTM and MC constructs share three components: locomotor, manipulative and stabilizing movements. In the present study, it was hypothesized that MC scores...
Hepatocellular carcinoma (HCC) is one of the most heterogeneous malignant cancers with no effective targets and treatments. However, the molecular pathogenesis of HCC remains largely uncertain. The aims of our study were to find crucial genes involved in HCC through multidimensional methods and revealed potential molecular mechanisms. Here, we reported the gene expression profile GSE121248 findings from 70 HCC and 37 adjacent normal tissues, all of which had chronic hepatitis B virus (HBV) infection,...
Background Stress and diseases such as endotoxemia induce cortisol synthesis through a complex biosynthetic pathway involving intermediates (progesterone, and 17α-hydroxyprogesterone (17α-OHP)) and suppression of the hypothalamus-pituitary-thyroid axis. Objective To measure plasma concentrations of cortisol, progesterone, 17α-OHP, and thyroid stimulating hormone (TSH) in dogs experimentally injected with intravenous...
Insects visit flowers not only to forage for nectar or pollen but also to search for hosts or prey, and to look for suitable habitats for breeding sites. In oil palm flowers, it has been documented that not all flower-visiting insects are pollinators, but some insects are recognized as predators, parasitoids or saprophages, which may affect the abundance and persistence of the weevil pollinating oil palm, Elaeidobius kamerunicus. We studied the community of oil palm flower-visiting insects and investigated...
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E3 ubiquitin ligases primarily determine the substrate specificity of the ubiquitin proteasome system and play an essential role in the resistance to bortezomib in multiple myeloma (MM). Neural precursor cell‐expressed developmentally downregulated gene 4–1 (NEDD4‐1, also known as NEDD4) is a founding member of the NEDD4 family of E3 ligases and is involved in the proliferation, migration, invasion, and drug sensitivity of cancer cells. In the present study, we investigated the role of NEDD4‐1 in...
Widespread adoption of primary human papillomavirus (HPV)‐based screening has encouraged the search for a triage test which retains high sensitivity for the detection of cervical cancer and precancer, but increases specificity to avoid overtreatment. Methylation analysis of FAM19A4 and miR124‐2 genes has shown promise for the triage of high‐risk (hr) HPV‐positive women. In this study, we assessed the consistency of FAM19A4/miR124‐2 methylation analysis in the detection of cervical cancer in a series...
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Abstract We present a case of salpingoliths detected in peritoneal washing, during an elective bilateral salpingo‐oophorectomy, in a 32 years old woman with history of familial BRCA gene mutation. Salpingoliths are psammoma body‐like types of calcification that originate from the fallopian tubes and can be encountered in peritoneal washings. Unlike psammoma bodies, salpingoliths have been tagged to benign and hyperplastic processes more often than neoplastic processes. Misinterpreting salpingoliths...
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Abstract Background Skin and soft‐tissue defects around the knee are common and their reconstruction is still challenging and argued. Thin, pliable and well‐vascularized tissues are required in order to restore the aesthetic appearance of the knee and facilitate joint function. Historically local muscle flaps were employed for the upper third of the lower limb reconstruction; however, since their introduction, different perforator flaps have been proposed for this purpose. The aim of this report...
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Background The presence of anaplastic lymphoma kinase (ALK) rearrangement predicts response to ALK tyrosine kinase inhibitor (TKI) therapy. Fluorescence in situ hybridization (FISH) was the initial reference standard to detect ALK rearrangement, but immunohistochemistry (IHC) using D5F3 has gained acceptance as an alternative diagnostic method. ALK IHC assays using other ALK antibodies have also been used as screening methods, but data supporting their utility as diagnostic tests have not been widely...
Background The classification of diffuse malignant mesothelioma into epithelioid, biphasic, and sarcomatoid types is based on histologic patterns. The diagnosis is made on biopsies, and because of intratumoral heterogeneity, they may not be representative of the entire tumor. The number and volume of biopsies needed to reach diagnostic accuracy in diffuse malignant mesothelioma and their prognostic value remain unclear. Methods This study examined 759 consecutive patients with pleural diffuse...
Background Although skeletal‐related events (SREs) are linked with a reduced quality of life and worse outcomes, to the authors' knowledge the factors that predict SREs are minimally understood. The objective of the current study was to identify predictors of SREs and all‐cause mortality among men with metastatic castration‐resistant prostate cancer (mCRPC). Methods Data were collected on 837 men with bone mCRPC at 8 Veterans Affairs medical centers within the Shared Equal Access Regional...
Background Fear of cancer recurrence (FCR) adversely affects quality of life. Cigarette smoking increases the risk of recurrence and may exacerbate FCR among survivors who smoke. FCR also may motivate quitting, but research on whether quitting reduces long‐term survivors' FCR is lacking. Among long‐term survivors of various cancers, the authors investigated relationships between quitting (vs smoking) and FCR, controlling for sociodemographic, cancer‐related, and health‐related variables. Methods...
Fanconi anemia (FA) is a rare inherited genetic condition that may lead to bone marrow failure, leukemia, and/or solid tumors. It is caused by the loss of function of at least 1 gene of the FA/BRCA pathway, which is necessary for DNA repair. Patients with FA have a 200‐fold to 1000‐fold risk of developing head and neck cancer, mainly oral squamous cell carcinoma (OSCC), and of doing so at a much younger age than individuals within the general population. Also, patients who have FA with OSCC have...
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Familial chylomicronemia syndrome is a rare genetic disorder characterized by reduced or absent lipoprotein lipase (LPL) activity. LPL mediates lipolysis of plasma triglycerides in chylomicrons and other triglyceride-rich lipoproteins, and its absence leads to marked fasting and postprandial…
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Presentation of Case. Dr. Kelsey Hills-Evans (Medicine): A 39-year-old woman with cyclic vomiting syndrome and polysubstance use disorder was seen in the emergency department of this hospital because of abdominal pain and vomiting. Eleven weeks before the current presentation, the patient was…
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Abstract Fungus is an antigen for bronchial asthma causing allergic bronchopulmonary mycosis (ABPM). As a therapy other than corticosteroids, itraconazole (ITCZ) is known to suppress the allergic inflammation induced by Aspergillus fumigatus (Af). However, the efficacy of liposomal amphotericin B (LAMB) with/without corticosteroid on ABPM is unknown. Mice sensitized to Dermatophagoides farinae (Df) allergen were intranasally infected with...
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