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Covering: June 2009 to 2021 Natural products containing a phloroglucinol motif include simple and oligomeric phloroglucinols, polycyclic polyprenylated acylphloroglucinols, phloroglucinol–terpenes, xanthones, flavonoids, and coumarins. These compounds represent a major class of secondary metabolites which exhibit a wide range of biological activities such as antimicrobial, anti-inflammatory, antioxidant and hypoglycaemic properties. A number of these compounds have been authorized for therapeutic use or are currently being studied in clinical trials. Their structural diversity and utility in both traditional and conventional medicine have made them popular synthetic targets over the years. In this review, we compile and summarise the recent synthetic approaches to the natural products bearing a phloroglucinol motif. Focus has been given on ingenious strategies to functionalize the phloroglucinol moiety at multiple positions. The isolation and bioactivities of the compounds are also provided. [ABSTRACT FROM AUTHOR]

Actinobacteria are one of the most intriguing bacterial phyla in terms of chemical diversity and bioactivities of their reported biomolecules and natural products, including various types of chiral molecules. Actinobacterial genera such as Detzia, Mycobacterium, and Streptomyces are among the microbial sources targeted for selective reactions such as asymmetric biocatalysis catalyzed by whole cells or enzymes induced in their cell niche. Remarkably, stereoselective reactions catalyzed by actinobacterial whole cells or their enzymes include stereoselective oxidation, stereoselective reduction, kinetic resolution, asymmetric hydrolysis, and selective transamination, among others. Species of actinobacteria function with high chemo-, regio-, and enantio-selectivity under benign conditions, which could help current industrial processing. Numerous selective enzymes were either isolated from actinobacteria or expressed from actinobacteria in other microbes and hence exploited in the production of pure organic compounds difficult to obtain chemically. In addition, different species of actinobacteria, especially Streptomyces species, function as natural producers of chiral molecules of therapeutic importance. Herein, we discuss some of the most outstanding contributions of actinobacteria to asymmetric biocatalysis, which are important in the organic and/or pharmaceutical industries. In addition, we highlight the role of actinobacteria as microbial cell factories for chiral natural products with insights into their various biological potentialities., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Color, which extends from the urban scale to the space scale, is important design elements expressing the unique visual and psychological identity of a settlement in the architecture. Every settlement has original color schemes formed with natural and human construction elements. The tinctorial designs in urban settlements in the present day have become gradually distant from natural and cultural elements because of the developing construction techniques after the industrial revolution. However, the vernacular architecture was able to preserve its color identity from the landscape, building façades, and interior space colors. In this study the environmental color mapping method is used for the determination of the prevalent colors. The environmental color mapping studies are made with an on‐site examination, the photographing in an unfiltered manner of the colors or with the specimen‐taking techniques. Subsequently, the averages are determined connected to the densities of the colors with the help of computer technologies. In this study, the Ayazini settlement sampling area was chosen, which was registered as a cultural heritage value connected to Afyonkarahisar Province. Ayazini, which is an extension of the Phrygian Valley, and that has a 6000‐year‐old past, is in a region where volcanic tufa rocks are found. The architectural fabric, the rock carvings, and the tufa building stone were formed with the shaping technique with the design of the inner spaces and the structural surfaces. The tufa rocks are the most important natural environmental elements, which determine the landscape, structure, and inner space character of Ayazini village. In this study, by taking the color change specimens occurring in the natural and artificial process of tufa rocks with the aim of producing the environmental color mapping of the Ayazini tufa, the averages connected to the densities of colors were determined. According to the data obtained at the end of the study, ıt was concluded that the dominant colors observed in the Ayazini tufa were khaki, pastel gray, ash gray, platinum, cadet gray, and armor gray. It is thought that these colors could be a reference for new designs with the landscape and architectural preservation activities that would be made at the settlement place. In this context, it is proposed for the colors obtained at the conclusion of the environmental color mapping to be used in the traditional house façades within the scope of the façade strengthening activities, which are continuing in the Ayazini region. [ABSTRACT FROM AUTHOR]

Polyvinylpyrrolidone/vinyl acetate (PVP/VA) is a molecule with increased adhesion capacity, and can be associated in the bacterial plaque control with sodium DNA, a natural anti-aging molecule able to improve gingival trophism. The aim of the study is to test at two weeks the antimicrobial and antiplaque properties, subjects affected by chronic periodontitis, showed by a mouthwash containing Chlorhexidine (CHX) 0.2% with Anti Discoloration System (ADS), PVP-VA, and Sodium DNA in comparison with a placebo mouthwash. A single center randomized controlled trial was conducted on a total of fifty-four (54) subjects. In the test Group (n = 27) patients were treated by a 0.2% Chlorhexidine (CHX) mouthwash with ADS, PVP-VA, and Sodium DNA, while a placebo mouthwash was used in the control Group (B). The full mouth plaque score (FMPS), full mouth bleeding score (FMBS), and gingival index (GI) were assessed at baseline, and at 1 and 2 weeks after treatment. FMPS score recorded at baseline (V2) was 52.7 ± 9.2 in the Group Test and 58.2 ± 6.1 in the Group Control (p > 0.05). After 1 week (V3), FMPS was 13.3 ± 5.6 in the Group Test and 18.7 ± 4.3 in the Group Control (p < 0.05), while at V4 (2 weeks), FMPS was 14.2 ± 4.1 in the Group Test and 20.3 ± 5.2 in the Group Control (p < 0.05). FMBS score recorded at baseline (V2) was 46.7 ± 8.7 in the Group Test and 49.2 ± 6.2 in the Group Control (p > 0.05). After 1 week (V3), FMBS was 12.7 ± 4.2 in the test Group Test and 18.5 ± 5.9 in the control Group Control (p < 0.05), while after 2 weeks (V4), it was 13.1 ± 3.2 in the Group Test and 19.8 ± 4.9 Group Control (p < 0.05). This trial has clinically showed the efficacy of a new formulation of chlorhexidine mouthwash in reducing bacterial plaque and gingival inflammation. A significant reduction of inflammation and bleeding scores was found in periodontal patients treated by a mouthwash containing CHX 0.2% with ADS, PVP-VA, and Sodium DNA compared to those treated with a placebo mouthwash. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the reliability and agreement of a new computerized planimetric method (CPM) for the measurement and assessment of plaque on all types of removable dental prostheses (RDPs).Materials and Methods: From a database containing 780 images taken following a standardized method for 65 RDPs, 55 images were randomly selected for image analysis. Adobe Photoshop software was used according to standard operating procedure (SOP) by one main examiner two times in different sessions, and one time by three additional examiners. To estimate the intra- and interexaminer reliability, intraclass correlation coefficient ICC(2,1) were used. Three parameters were used to estimate agreement: standard error of measurement (SEM), smallest detectable change at the 95% confidence level (SDC95%), and limits of agreement (LoA) according to the Bland-Altman method.Results: In all steps of the image analysis, both intra- and interexaminer reliability were excellent, with ICC(2,1) values > 0.85 at the 95% confidence level. The intra- and interexaminer values for both the SEMagreement and SDC95% were ≤ 6% and ≤ 17%, respectively. The Bland-Altman analysis revealed a satisfactory level of agreement.Conclusion: This study shows excellent inter- and intraexaminer reproducibility, a satisfactory level of examiner agreement, and acceptable measurement error. Furthermore, the method can be used with all types of RDPs. The CPM is more suitable for clinical research because of its objectivity, reliability, high level of standardization, and ability to detect and quantify small changes in plaque. [ABSTRACT FROM AUTHOR]

The article discusses that American Economic Journal: Applied Economics publishes papers on a wide range of topics in applied economics, with a focus on empirical papers. It mentions that journal covers including development microeconomics, economic history, economics of the family, education, and environmental economics.

Oral conditions such as gingivitis and oral malodor are commonly reported globally. Objective: This investigation clinically stratified subjects to healthy, malodor and gingivitis groups and enumerated oral polymorphonuclear leukocytes (PMN) as a measure of inflammation prior to and after rinsing with a chlorhexidine (CHX) mouthwash. The study also assessed clinical outcomes (dental plaque and gingival bleeding indices), malodor (halimeter scores, organoleptic and tongue coat index and microbiological parameters (anaerobic and malodor organisms of dental plaque, tongue surface and saliva) for a comprehensive assessment of the oral inflammatory burden. Methods: Consenting adults were stratified into control (n = 17), gingivitis (n = 19) and halitosis (n = 17) groups based on clinical criteria. At baseline, oral samples were examined for PMN in addition to microbiological analysis of dental plaque, saliva and tongue scrapings for anaerobic and malodor bacteria. Subjects were issued a commercially available fluoride toothpaste and a chlorhexidine mouthwash for two-week use prior to post-treatment assessments identical to baseline. Results: At baseline, PMN were lowest in the control that increased amongst the halitosis subjects, with the gingivitis group registering the highest levels (p < 0.05) with these outcomes corresponding with clinical parameters (p < 0.05). CHX use improved outcomes with a 56–61% reduction in PMN with significant differences between groups (p < 0.05). Dental plaque and bleeding indices were lower by 57–78% with oral malodor, demonstrating reductions of 33–59% (p < 0.05). Significant reductions in anaerobic and malodor organisms ranging from 78–96% and 76–94%, respectively, were noted after CHX use (p < 0.05). Conclusions: At study enrollment, PMN scores were lowest in healthy subjects, with increasing numbers amongst halitosis followed by gingivitis. Amongst all subject groups, CHX use significantly reduced oral PMN and corroborated with corresponding decreases in clinical, malodor and bacterial outcomes. Together, these results demonstrate the significant reductions in the oral inflammatory burden following CHX use. [ABSTRACT FROM AUTHOR]

Understanding crystal structures and behaviors is crucial for constructing and engineering crystalline materials with various properties and functions. Recent advancement in three-dimensional electron diffraction (3D ED) and its application on structural characterizations have expanded single-crystal analysis into nano-sized materials. Herein, we provide an overview on 3D ED, including its development, data collection protocols, and their applications for investigating crystal structures. We focus on metal-organic frameworks (MOFs) and small-molecule-based organic crystals, and highlight the insights provided by 3D ED such as structure-property relationships, polymorphism, hydrogen bonding, and crystal chirality, which are crucial subjects in crystal engineering. With more and more laboratories setting up 3D ED techniques, we envision that it will not only continue providing critical structural information, but also establish a wide impact on chemistry, materials science and life science. [ABSTRACT FROM AUTHOR]

The nitrogen–nitrogen bond is a core feature of diverse functional groups like hydrazines, nitrosamines, diazos, and pyrazoles. Such functional groups are found in >300 known natural products. Such N–N bond-containing functional groups are also found in significant percentage of clinical drugs. Therefore, there is wide interest in synthetic and enzymatic methods to form nitrogen–nitrogen bonds. In this review, we summarize synthetic and biosynthetic approaches to diverse nitrogen–nitrogen-bond-containing functional groups, with a focus on biosynthetic pathways and enzymes. [ABSTRACT FROM AUTHOR]

Microcrystal electron diffraction (MicroED) has established its complementary role alongside X-ray diffraction in crystal structure elucidation. Unfortunately, kinematical refinement of MicroED data lacks the differentiation power to assign the absolute structure solely based on the measured intensities. Here we report a method for absolute configuration determination via MicroED by employing salt formation with chiral counterions. [ABSTRACT FROM AUTHOR]

The synthesis of enantiopure chiral boron dipyrromethenes (BODIPYs) is of importance due the intrinsic properties of BODIPYs as fluorophores that could be used as probes for molecular sensing. The present study reports an asymmetric organocatalytic cascade reaction of meso‐chloromethyl BODIPY derivatives with α,β‐unsaturated aldehydes catalyzed by a chiral secondary amine. The corresponding BODIPY‐derived cyclopropanes were produced in isolated yields 66–98%, and with diastereomeric ratios 3/2–>20/1, and 92–99% ee for major diastereomer. The synthetic utility of the protocol was exemplified on a set of additional transformations of the corresponding optically pure compounds. In addition, a study explaining the reaction mechanism (DFT computations) and photophysical characterization of all enantioenriched products were accomplished. [ABSTRACT FROM AUTHOR]

Evidence on prophylactic radiotherapy (RT) in hip heterotopic ossification (HO) is sparse and conflicting. The aim of this literature review was to collect and summarize the available data on RT efficacy in preventing hip HO. The results of this review show that RT is effective in the prevention of hip HO, albeit with large variability across series. Effective prophylactic RT requires optimal treatment fields and time intervals with surgery. On the contrary, there is no clear evidence on the optimal timing (post-operative versus pre-operative RT). Comparisons between prophylactic RT and use of non-steroidal antiinflammatory drugs showed conflicting results, although most were in favor of RT. In conclusion, RT is an established prophylactic treatment for hip HO. However, optimal dose, technique and timing remain unclear, as does the usefulness of combining RT with drugs. [ABSTRACT FROM AUTHOR]

Alkylation of one of the inner-core nitrogen atoms is one possible approach to obtain dianionic corrole ligands, suitable for the coordination of divalent metal ions, such as Pd II . Inner-core N-methylation can be obtained by treating the corrole with CH 3 I, but the reaction conditions should be optimized to limit the formation of the dimethylated derivative. Two regioisomers, the N-21 and the N-22 methyl derivatives are obtained from the reaction, with the first product achieved in a higher amount. Structural characterization of the reaction products evidenced the distortion induced by the introduction of the methyl groups; the N-methylcorroles are chiral compounds, and the enantiomers were separated by chromatography, with their absolute configuration assigned by ECD computation. Palladium insertion was achieved in the case of monosubstituted corroles, but not with the dimethylated macrocycle; X-ray characterization of the complexes showed the distortion of the macrocycles. The Pd complexes do not show luminescence emission, but are able to produce singlet oxygen upon irradiation. The Pd II complexes were also inserted in human serum albumin (HSA) and dispersed in water; in this case, the protein protects the corroles from photobleaching, and a switch from the type II to the type I mechanism in reactive oxygen species (ROS) production is observed., (© 2023 Wiley-VCH GmbH.)

Since the development of the first method for porphyrin synthesis by Rothemund in 1935, porphyrin derivatives have been widely investigated and have played an essential role in chemical sciences. Most synthetic routes of porphyrins involve oxidative aromatization. Herein, we present a synthetic method to produce ABCD-porphyrins, including chiral ones, through a one-pot reaction involving "coordination, cyclization, and dehydrative aromatization" using a mono-dipyrrinatoPt(II)Cl(COE) (COE=cyclooctene) complex as a platinum template., (© 2023 Wiley-VCH GmbH.)

Objective: To assess whether there is sufficient evidence of a difference in efficacy between subgingival air polishing (SubAP) and subgingival debridement as periodontal support treatment. The systematic review protocol was registered in the PROSPERO database under no. CRD42020213042., Methods: A comprehensive search was conducted using eight online databases to develop straightforward clinical questions and search strategies, from their inception to 27 January 2023. The references of identified reports were also retrieved for inclusion in the analysis. The risk-of-bias of the included studies was evaluated using the Revised Cochrane Risk-of-Bias tool (RoB 2). A meta-analysis was performed on five clinical indicators using the Stata 16 software., Results: Twelve randomized controlled trials were ultimately included, and most included studies had varying degrees of risk-of-bias. The results of the meta-analysis indicated that there was no significant difference between SubAP and subgingival scaling in terms of improving probing depth (PD), clinical attachment loss (CAL), plaque index (PLI), and bleeding on probing% (BOP%). The results of the visual analogue scale score analysis indicated that SubAP produced less discomfort than did subgingival scaling., Discussion: SubAP can provide better treatment comfort than subgingival debridement. There was no significant difference in the efficacy of the two modalities in improving PD, CAL, and BOP% in supportive periodontal therapy., Conclusion: Currently, evidence for assessing the difference in the efficacy of SubAP and subgingival debridement in improving the PLI is insufficient, and further high-quality clinical studies are needed., (© 2023. The Author(s), under exclusive licence to British Dental Association.)

A new class of siloxane-based cations with hidden silylium-type reactivity is provided, which, in combination with an arylborate counteranion, initiates a highly selective para-C(sp2)–F defunctionalization of a perfluorinated aryl group. The hydrodefluorinated aryl borane is obtained as a crystalline solid via continuous sublimation during the reaction. The heterocyclic six-membered cation could be obtained single-crystalline after dehydrogenative anion exchange. DFT calculations give insight into the bonding within the siloxane-based cation and the mechanism of the ion pair reaction. [ABSTRACT FROM AUTHOR]

Both geometric architecture and electronic configurations of heme proteins contribute to its activity. In this work we designed and synthesized a series of four copper(II) porphyrin complexes (4‐, 3‐, 2‐ and 1‐Cu) where the molecular conformations are modulated by a pair of stepwise shortened straps on the same porphyrin side (cis‐ortho) to give double bow‐shaped skeletons. Single crystal structures demonstrate that the straps gradually increase the saddle deformation and the deviation of the metal centers, which is in accordance with two, unusual d‐orbital reconstructions of two different ground states, as revealed by 4 K EPR and DFT calculations. In the study of the electrocatalytic hydrogen evolution reaction (HER), 1‐Cu, with the shortest straps, showed the most apparent improvement of activity. Second coordination sphere (SCS) effects created by the double bow‐shaped architecture and the strong saddle porphyrin core in 1‐Cu are found to play key roles in proton trapping during the catalytic process. The work contributes a novel strategy to improve the catalytic performance of heme analogs through ligand geometric modulation. [ABSTRACT FROM AUTHOR]

Micro‐batteries are attractive miniaturized energy devices for new Internet of Things applications, but the lack of understanding of their degradation process during cycling hinders improving their performance. Here focused ion beam (FIB)‐lamella from LiMn1.5Ni0.5O4 (LMNO) thin‐film cathode is in situ cycled in a liquid electrolyte inside an electrochemical transmission electron microscope (TEM) holder to analyze structural and morphology changes upon (de)lithiation processes. A high‐quality electrical connection between the platinum (Pt) current collector of FIB‐lamella and the microchip's Pt working electrode is established, as confirmed by local two‐probe conductivity measurements. In situ cyclic voltammetry (CV) experiments show two redox activities at 4.41 and 4.58/4.54 V corresponding to the Ni2+/3+ and Ni3+/4+ couples, respectively. (S)TEM investigations of the cycled thin‐film reveal formation of voids and cracks, loss of contact with current collector, and presence of organic decomposition products. The 4D STEM ASTAR technique highlights the emergence of an amorphization process and a decrease in average grain size from 20 to 10 nm in the in situ cycled electrode. The present findings, obtained for the first time through the liquid electrochemical TEM study, provide several insights explaining the capacity fade of the LMNO thin‐film cathode typically observed upon cycling in a conventional liquid electrolyte. [ABSTRACT FROM AUTHOR]

This study presents a method of high-precision stable Sr isotope measurement for barite using the Na2CO3 exchange reaction and MC-ICP-MS. The reliability of this method was strictly tested by measurement of the synthetic barite standard. The synthetic barites were made by mixing the natural barite standard GBW07814 with three strontium-rich matrix rocks (carbonate JLs-1, andesite AGV-2, and black shale SGR-1) in different proportions. The average 87Sr/86Sr and δ88Sr of synthetic barites are 0.713556 ± 0.000013 (2SD, n = 22) and −0.07 ± 0.02‰ (2SD, n = 22), respectively, which are consistent with the values of GBW07814 (87Sr/86Sr of 0.713555 ± 0.000023, 2SD, n = 46 and δ88Sr of −0.06 ± 0.02‰, 2SD, n = 28). High recovery in the exchange reaction was achieved by using excessive Na2CO3 to avoid Sr isotope fractionation. Furthermore, the potential matrix effects in chemical purification were rigorously evaluated by analyzing the synthetic solution made by mixing SRM987 and matrix elements. The average δ88Sr of the synthetic solution is −0.01 ± 0.04‰ (2SD, n = 4), consistent with the δ88Sr of SRM987 (0.00‰). Based on long-term analyses of USTC-Sr (pure Sr solution), the external precision of δ88Sr was found to be better than 0.03‰ (2SD, n = 92). We further measured the 87Sr/86Sr and δ88Sr of five natural barite standards (GBW07811, GBW07812, GBW07814, GBW07815 and GBW07816), revealing significant stable Sr isotope fractionation in natural barites by 0.37‰. [ABSTRACT FROM AUTHOR]

Interactions of two chromophores such as carbonyl groups yield a strong VCD couplet that reflects the molecular structures. The use of VCD couplets for biomacromolecular structural studies has been hampered by severe signal overlap caused by numerous functional groups that originally exist in biomacromolecules. Nitrile, isonitrile, alkyne, and azido groups show characteristic IR absorption in the 2300-2000 cm-1 region, where biomolecules do not strongly absorb. We herein examined the usefulness of these functional groups as chromophores to observe a strong VCD couplet that can be readily interpreted using theoretical calculations. Studies on a chiral binaphthyl scaffold possessing two identical chromophores showed that nitrile and isonitrile groups generate moderately-strong but complex VCD signals due to anharmonic contributions. The nature of their anharmonic VCD patterns is discussed by comparison with the VCD spectrum of a mono-chromophoric molecule and by anharmonic DFT calculations. On the other hand, through studies on diazido binaphthyl and diazido monosaccharide, we demonstrated that the azido group is more promising for structural analysis of larger molecules due to its simple, strong VCD couplet whose spectral patterns are readily predicted by harmonic DFT calculations. [ABSTRACT FROM AUTHOR]

The medically important bacterial aromatic polyketide natural products typically feature a planar, polycyclic core structure. An exception is found for the rubromycins, whose backbones are disrupted by a bisbenzannulated [5,6]‐spiroketal pharmacophore that was recently shown to be assembled by flavin‐dependent enzymes. In particular, a flavoprotein monooxygenase proved critical for the drastic oxidative rearrangement of a pentangular precursor and the installment of an intermediate [6,6]‐spiroketal moiety. Here we provide structural and mechanistic insights into the control of catalysis by this spiroketal synthase, which fulfills several important functions as reductase, monooxygenase, and presumably oxidase. The enzyme hereby tightly controls the redox state of the substrate to counteract shunt product formation, while also steering the cleavage of three carbon‐carbon bonds. Our work illustrates an exceptional strategy for the biosynthesis of stable chroman spiroketals. [ABSTRACT FROM AUTHOR]

We report the design of a synthetically easy accessible axial chirality-inducing framework for a chromophore of choice. The scaffold consists of two basic para-phenylene-ethynylene backbones separated by laterally placed corner units. Substitution with an inherently achiral chromophore at the 2 and 5 positions of the central phenylene excitonically couples the chromophore associated transition and thereby results in chiroptical properties. Using 6-methoxynaphthalene as a model chromophore, we present the synthesis, structural analysis and spectroscopic investigation of the framework. The chiral framework was synthesized in three straightforward synthetic steps and fully characterized. The obtained racemic compounds were resolved using HPLC and assignment of the absolute configuration was performed using the exciton chirality method, crystallography and DFT calculations. This simple yet potent framework might prove useful to enrich the structural diversity of chiral materials. [ABSTRACT FROM AUTHOR]

Background: plaque accumulation is the major cause of gingivitis and fixed orthodontic appliances contribute to plaque retention and interfere with the performance of good oral hygiene. The aim of this study is to assess if the superfloss adds a benefit for the gingival health in patients with lower lingual permanent retainer by detecting the differences in debris accumulation, plaque and calculus formation and signs of gingival inflammation when using superfloss. Design: randomized prospective case control study. Methods: a group of fifty six patients who just recently received a lower lingual fixed orthodontic retainer were enrolled in this study. Oral hygiene index was measured at baseline and they had a professtional scaling and oral hygiene instructions. They were divided into two groups, one group was instructed to use the superfloss in addition to their dental home care, the other group were not instructed to use the superfloss. Both groups were recalled after eight weeks to measure plaque index, gingival index, calculus index, sulcus bleeding index and oral hygiene index. Results: the oral hygiene index for the two groups was comparable at both baseline and recall but there were differences between both groups in plaque index, gingival index, calculus index and sulcus bleeding index, with the study group had lower scores. Conclusion: the superfloss use resulted with better gingival health, and should be used as an interdental cleaning aid in patients with lower lingual permanent retainer. [ABSTRACT FROM AUTHOR]

Background: The side effects of present antimicrobials like chlorhexidine (CHX) and the emergence of drug resistance necessitate the development of alternative agents to control dental caries. Aim: This study developed a novel small molecule, namely II-6s, and investigated its antimicrobial activities against common oral streptococci associated with dental caries. Methods: The susceptibility of streptococci to II-6s was evaluated by the microdilution method, time-kill assay and scanning electron microscopy. The exopolysaccharides, dead/live bacteria and bacterial composition of the II-6s-treated Streptococcus mutans/Streptococcus gordonii/Streptococcus sanguinis 3-species biofilms were analyzed by confocal laser scanning microscopy, fluorescent in situ hybridization and quantitative PCR. The anti-demineralization effect and cytotoxicity of II-6s were evaluated by transverse microradiography and CCK-8 assay, respectively. Repeated exposure of S. mutans to II-6s was performed to assess if II-6s could induce drug resistance. Results: II-6s exhibited antimicrobial activity similar to CHX against S. mutans, S. gordonii and S. sanguinis and significantly inhibited exopolysaccharides production, live bacteria and the demineralizing capability of the 3-species streptococcal biofilms. Besides, II-6s showed reduced cytotoxicity relative to CHX and did not induce drug resistance in S. mutans after 15 passages. Conclusion: - II-6s may serve as a promising part of a successful caries management plan. [ABSTRACT FROM AUTHOR]

Peru Balsam, a resinous substance derived from Myroxylon balsamum var. pereirae, has historically been used as a topical ointment for various skin conditions such as scabies, poorly healing wounds, eczema, and haemorrhoids. The ingredients responsible for these properties are not fully elucidated. We investigated the chemical composition of two Peru Balsam samples, one historical and one modern, using gas chromatography/mass spectrometry to identify the active ingredients responsible for its pharmaceutical properties. Both Peru Balsam specimens investigated had similar compositions, showing the stability of the substance. Components identified are effective against scabies, exhibit antimicrobial activity and aid skin penetration. These properties are consistent with historical uses of Peru Balsam. Several ingredients are also known allergens. This study, combining chemical information with scientific literature related to pharmaceutical properties of natural substances, represents a breakthrough in the elucidation of active ingredients in Peru Balsam. [ABSTRACT FROM AUTHOR]

In this article, we reflect on the particular temporal structure of pregnancies and prenatal entities with the aim to contribute to the field of the sociology of pregnancy. Medical models and technology shape today's notion of pregnancy as a linear, nine-month developmental process that leads to the birth of a child. Through ultrasound technology and prenatal examinations, prenatal entities have thus historically gained a present 'being' as a developing, unborn child. While these ideas undoubtedly greatly influence the participants' interpretations, a culturalistic perspective on time alone does not do justice to the phenomenon's lived tensions and the temporal complexity of the phenomenon. From a Schutzian perspective of time, we have worked out how practices of pregnancy and the production of meaning are shaped by an interwoven back and forth between orientations to the past, present and future. Drawing on relevant works from the sociology of pregnancy, we work out five modes of temporal references that mold the phenomenon of pregnancy: joint imagination of the couple, in which the (un)born is anticipated as fantasies of the future (1), passivities of pregnancy, in which the desired future is experienced as unable to influence (2), the presentification of the unborn in and through visual and bodily-somatic contact moments (3), its futurization through the cultivation of a 'not-yet' (4) and prenatal losses, as a critical rupture with the anticipated and desired future (5). Our analysis underlines the potential of a time sociological perspective on pregnancy and the constitution of relationships and persons. [ABSTRACT FROM AUTHOR]

Two novel aza-BODIPY derivatives are synthesized, with the fluorine atoms in the BF 2 moiety replaced by cyano groups. The introduction of cyano groups changes the phenyl substituents on the 3,5 positions from parallel to antiparallel. The HOMO/LUMO energy levels are stabilized gradually upon increasing the number of cyano groups, and the photophysical properties show corresponding shifts. With high thermal stability, the derivatives can be purified by sublimation and used to prepare vacuum-deposited thin films. This research extends the aza-BODIPY family with cyano-substituted derivatives., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objectives: To assess the safety and efficacy of an oleanolic acid (OA)‐containing toothpaste in reducing gingival inflammation and plaque in patients with gingivitis. Methods: This proof‐of‐concept parallel, double‐blind, randomized controlled clinical trial included 99 patients. Following a 1‐week washout, patients were randomized into three groups: OA group (fluoride toothpaste containing 0.1% OA and placebo mouthwash); negative control (fluoride toothpaste and placebo mouthwash); and CHX group (fluoride toothpaste and 0.12% chlorhexidine mouthwash). Patients were clinically assessed at inclusion, pre‐washout visit, baseline and after 4 days, 1 week and 2 weeks of twice‐daily use of the products. Patients received a diary for documentation of bleeding on brushing and provided unstimulated saliva samples. Results: After two weeks, all groups showed significant reductions in all clinical parameters. The CHX group exhibited significantly greater reductions in gingival index and interproximal gingival index scores at week 2, as compared to patients in the negative control (p = 0.04). In contrast, reductions in gingival index scores did not differ between CHX and OA groups and between OA and negative control groups at week 2. The CHX group had significantly greater reductions in plaque index scores at day‐4, 1‐week and 2‐week evaluations, as compared to the negative control and OA groups. The frequency of adverse events was similar among the groups. None of the groups reduced salivary transferrin levels. Finally, the OA group had the lowest percentage of self‐reported bleeding events. Conclusion: OA toothpaste failed to provide antiplaque and antigingivitis effects superior to those of a fluoride toothpaste after 2 weeks of use. [ABSTRACT FROM AUTHOR]

The recent outbreak of the COVID-19 pandemic is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which infects human epithelial tissue by interaction of the receptor-binding domain of its spike protein (S-protein) with angiotensin-converting enzyme 2 (ACE2). Herein, we synthesized suitably configured Tröger's bases (TB-1/2/3) and investigated molecular docking of TBs at the interface of SARS-CoV-2 S-protein and ACE2, which revealed a high docking score indicating strong binding. Detailed analysis of docking highlights strong binding of TB-2 into the interfacial domain of SARS-CoV-2 S-protein and ACE2. Furthermore, for the first time, we explored surface-enhanced Raman scattering (SERS) modality to assess intermolecular interactions between TBs and SARS-CoV-2 S-protein and ACE2. [ABSTRACT FROM AUTHOR]

We study the influence of the physical and chemical structure on the chiroptical response of fluorene-based polymeric systems, namely poly(9,9-dioctylfluorene) (PFO) and the donor–acceptor type copolymer poly(9,9-dioctylfluorene-alt-benzothiadiazole) (F8BT). We reveal the significance of electric-magnetic coupling, at both short (molecular-level) and intermediate (delocalised over multiple polymer chains) length scales, on the magnitude of the dissymmetry. These findings provide a framework for the design of new materials with an enhanced chiroptical response. [ABSTRACT FROM AUTHOR]

The direct 3,3′-dimerization of BODIPYs lacking substituent groups in the 1,2,6, and 7 positions was developed by oxidative coupling with FeCl3. This regioselective dimerization was achieved for BODIPYs substituted only in the 5-position with Cl or aryl groups. Further functionalization of the 5,5′-dichloride dimer gave the corresponding pyrrole or 4-(2-aminoethyl)morpholine disubstituted dimers 2f and 2g, respectively. While dimer 2f exhibited intense NIR absorption/emission maxima at 773/827 nm in toluene, dimer 2g showed favorable lysosome-targeting NIR fluorescence in living cells. [ABSTRACT FROM AUTHOR]

Covering: Up to December 2020 Enzymatic halogenation reactions are essential for the production of thousands of halogenated natural products. However, in recent years, scientists discovered several halogenases that transiently incorporate halogen atoms in intermediate biosynthetic molecules to activate them for further chemical reactions such as cyclopropanation, terminal alkyne formation, C-/O-alkylation, biaryl coupling, and C–C rearrangements. In each case, the halogen atom is lost in the course of biosynthesis to the final product and is hence termed "cryptic". In this review, we provide an overview of our current knowledge of cryptic halogenation reactions in natural product biosynthesis. [ABSTRACT FROM AUTHOR]

Purpose: This in vitro study was undertaken to investigate the antimicrobial effect of distinctive oral mouth washes after the addition of zein-coated (Magnesium oxide) MgO nanoparticles on exemplary of some oral microorganisms. Materials and Methods: Three hundred and twelve samples were used in this study. A set of five concentrations of MgO nanoparticles with zein and without zein-coating were incorporated into three oral mouth washes: Listerine zero, Listerine total control and Oral B in the mass percentages of 0.3%, 0.5%, 1%, 2%, 5% and 10%, in addition to controls with no MgO nanoparticles. The antimicrobial effect of three mouth washes with variable concentrations of MgO was tested against the following organisms: Staphylococcus aureus, Streptococcus mutans, Enterococcus faecalis and Candida albicans using the disc diffusion test (DDT) and direct contact test (DCT). Data were analyzed using one-way ANOVA statistical test. Results: The tested mouthwashes with zein-coated MgO nanoparticles showed significant differences of antimicrobial activity on S. mutans, S. aureus, E. faecalis, and C. albicans in the disc diffusion test. While in the DCT, all tested mouthwashes with MgO nanoparticles with and without zein coating showed antimicrobial activity on all tested microorganisms. Conclusion: Zein-coated MgO nanoparticles may be considered as a potential antimicrobial agent when added to oral mouthwashes. Future analysis, including in vivo studies, is required in order to incorporate zein/MgO nanoparticles into oral mouthwashes that may improve its antibacterial property. [ABSTRACT FROM AUTHOR]

Axially chiral compounds have been always considered a laboratory curiosity with rare prospects of being applied in asymmetric synthesis. Things have changed very quickly in the last twenty years when it was understood the important role and the enormous impact that these compounds have in medicinal, biological and material chemistry. The asymmetric synthesis of atropisomers became a rapidly expanding field and recent reports on the development of N-N atropisomers strongly prove how this research field is a hot topic open to new challenges and frontiers of asymmetric synthesis. This review focuses on the recent advances in the enantioselective synthesis of N-N atropisomers highlighting the strategies and breakthroughs to obtain this novel and stimulating atropisomeric framework., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Cihunamides A-D (1-4), novel antibacterial RiPPs, were isolated from volcanic-island-derived Streptomyces sp. The structures of 1-4 were elucidated by 1 H, 13 C, and 15 N NMR, MS, and chemical derivatization; they contain a tetrapeptide core composed of WNIW, cyclized by a unique C-N linkage between two Trp units. Genome mining of the producer strain revealed two biosynthetic genes encoding a cytochrome P450 enzyme and a precursor peptide. Heterologous co-expression of the core genes demonstrated the biosynthesis of cihunamides through P450-mediated oxidative Trp-Trp cross-linking. Further bioinformatic analysis uncovered 252 homologous gene clusters, including that of tryptorubins, which possess a distinct Trp-Trp linkage. Cihunamides do not display the non-canonical atropisomerism shown in tryptorubins, which are the founding members of the "atropitide" family. Therefore, we propose to use a new RiPP family name, "bitryptides", for cihunamides, tryptorubins, and their congeners, wherein the Trp-Trp linkages define the structural class rather than non-canonical atropisomerism., (© 2023 Wiley-VCH GmbH.)

Within density functional theory, the adsorption of the H2Pc molecule on the (3 × 3) silicene/(4 × 4) Ag(111) surface has been investigated. We observe an electronic redistribution in the central macrocycle of the H2Pc molecule and the formation of two Si−N covalent bonds between the molecule and the silicene, in agreement with a cycloaddition reaction. However, while on SiC(0001)(3 × 3) or Si(111)(√3×√3)R30◦-boron, the H2Pc molecule remains planar, and the H2Pc molecule takes a butterfly conformation on the silicene/Ag substrate due to an electrostatic or a polarization repulsion between the molecule and the silicene. Our study opens a way to the experimental adsorption of large organic molecules on supported silicene. [ABSTRACT FROM AUTHOR]

Deformable image registration (DIR) is a popular technique for the alignment of digital images, with highly relevant applications in medical image analysis. However, the numerical solution of DIR problems can be very challenging in computational terms, as the improvement of the DIR solution typically involves a uniform refinement of the underlying domain discretization that exponentially increases the number of degrees of freedom. In this work, we develop adaptive mesh refinement schemes particularly designed for the finite-element solution of DIR problems. We start by deriving residual-based a posteriori error estimators for the primal and mixed formulations of the DIR problem and show that they are reliable and efficient. Based on these error estimators, we implement adaptive mesh-refinement schemes into a finite-element code to register images. We assess the numerical performance of the proposed adaptive scheme on smooth synthetic images, where numerical convergence is verified. We further show that the adaptive mesh refinement scheme can deliver solutions to DIR problems with significant reductions in the number of degrees of freedom without compromising the accuracy of the solution. We also confirm that the adaptive scheme proposed for the mixed DIR formulation successfully handles volume-constrained registration problems, providing optimal convergence in analytic examples. To demonstrate the applicability of the method, we perform adaptive DIR on medical brain images and binary images and study how image noise affects the proposed refinement schemes. [ABSTRACT FROM AUTHOR]

Fullerene extracts obtained from fullerene soot lack their real application due to their poor solubility in common solvents and difficulty in purification. Encapsulation of these extracts in a suitable host is an important approach to address these issues. We present a new Pd6 barrel (1), which is composed of three 1,4‐dihydropyrrolo[3,2‐b]pyrrole panels, clipped through six cis‐PdII acceptors. Large open windows and cavity make it an efficient host for a large guest. Favorable interactions between the ligand and fullerene (C60 and C70) allows the barrel to encapsulate fullerene efficiently. Thorough investigation reveals that barrel 1 has a stronger binding affinity towards C70 over C60, resulting in the predominant extraction of C70 from a mixture of the two. Finally, the fullerene encapsulated barrels C60⊂1 and C70⊂1 were found to be efficient for visible‐light‐induced singlet oxygen generation. Such preferential binding of C70 and photosensitizing ability of C60⊂1 and C70⊂1 are noteworthy. [ABSTRACT FROM AUTHOR]

Herein, we report a comprehensive study on the lanthanide‐directed coordination self‐assembly with two bis‐tetradentate acylhydrazone ligands H4L1 and H4L2. Multifarious outcomes, which are base‐ and metal‐dependent, were revealed by NMR, ESI‐TOF‐MS and X‐ray crystallography. In the absence of base, bent H4L1 was assembled into dinuclear double‐strand helicate Ln2(H2L1)2 by partially‐deprotonated assembly with La, Sm or Eu, while trinuclear Ln3(H2L1)3 with Yb or Lu. For linear H4L2, infinite 1D zig‐zag metal‐organic polymeric chain (Ln2H2L2)n was obtained. However, complete deprotonated L1 and L2 assembled into discrete trinuclear Ln3(L1/2)3 and tetranuclear Ln4(L1/2)4 macrocyclic structures under the basic condition. For these, there are multiple possible isomers coexisting in the solution which were enumerated and simulated with molecular mechanic modeling. Visible‐light sensitized NIR emissions on the Yb complexes have been observed, endowing them potential application in photofunctional materials. [ABSTRACT FROM AUTHOR]

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This work introduces and analyzes new primal and dual-mixed finite element methods for deformable image registration, in which the regularizer has a nontrivial kernel, and constructed under minimal assumptions of the registration model: Lipschitz continuity of the similarity measure and ellipticity of the regularizer on the orthogonal complement of its kernel. The aforementioned singularity of the regularizer suggests to modify the original model by incorporating the additional degrees of freedom arising from its kernel, thus granting ellipticity of the former on the whole solution space. In this way, we are able to prove well-posedness of the resulting extended primal and dual-mixed continuous formulations, as well as of the associated Galerkin schemes. A priori error estimates and corresponding rates of convergence are also established for both discrete methods. Finally, we provide numerical examples confronting our formulations with the standard ones, which prove our finite element methods to be particularly more efficient on the registration of translations and rotations, in addition for the dual-mixed approach to be much more suitable for the quasi-incompressible case, and all the above without losing the flexibility to solve problems arising from more realistic scenarios such as the image registration of the human brain. [ABSTRACT FROM AUTHOR]