A Radical Approach for Asymmetric α-C-H Addition of N-Sulfonyl Benzylamines to Aldehydes.

Efficient synthesis of enantioenriched amines is of great importance due to their significant synthetic and biological applications. Photoredox-mediated asymmetric α-amino C(sp3)-H functionalization offers an atom-economical and sustainable approach to access chiral amines. However, the development of analogous reactions is in its early stages, generally affording chiral amines with a single stereocenter. Herein, we present a novel synergistic triple-catalysis approach for the asymmetric α-C-H addition of readily available N-sulfonyl amines to aldehydes under mild conditions. This method allows for the efficient synthesis of a diverse array of valuable ß-amino alcohols bearing vicinal stereocenters. Unlike previous reports, our protocol employs a radical approach using earth-abundant Cr catalysis. Quinuclidine plays a dual role by facilitating highly selective hydrogen-atom transfer to generate α-amino radicals and promoting the dissociation of the Cr-O bond, which is crucial for the overall catalytic cycle as evidenced by control, NMR, and DFT experiments. Preliminary mechanistic studies, including radical trapping, nonlinear effect, Stern-Volmer plot, kinetic isotope effect, and Hammett plot, offer valuable insights into the reaction pathway.

Single-Walled Cluster Nanotubes for Single-Atom Catalysts with Precise Structures.

Spatially confining isolated atomic sites in low-dimensional nanostructures is a promising strategy for preparing high-performance single-atom catalysts (SACs). Herein, fascinating polyoxometalate cluster-based single-walled nanotubes (POM-SWNTs) with atomically precise structures, uniform diameter, and single-cluster wall thickness are constructed by lacunary POM clusters (PW11 and P2W17 clusters). Isolated metal centers are accurately incorporated into the PW11-SWNTs and P2W17-SWNTs supports. The structures of the resulting MPW11-SWNTs and MP2W17-SWNTs are well established (M = Cu, Pt). Molecular dynamics simulations demonstrate the stability of POM-SWNTs. Furthermore, the turnover frequency of PtP2W17-SWNTs is 20 times higher than that of PtP2W17 cluster units and 140 times higher than that of Pt nanoparticles in the alcoholysis of dimethylphenylsilane. Theoretical studies indicate that incorporating a Pt atom into the P2W17 support induces straightforward electron transfer between them, combining the nanoconfined environment to enhance the catalytic activity of PtP2W17-SWNTs. This work shows the feasibility of using subnanometric POM clusters to assemble single-walled cluster nanotubes, highlighting their potential to prepare superior SACs with precise structures.

A Tailorable Series of Elastomeric-To-Rigid, Selfhealable, Shape Memory Bismaleimide.

In recent years, there has been rapid development in the field of shape memory materials with active deformation performance. However, bismaleimide, a widely used thermosetting material in aerospace, has been largely overlooked in shape memory applications. This work presents the synthesis of a molecule containing an alkene bond adjacent to an oxygen atom. Through molecular design, a one-time reaction between this specialized molecule and the bismaleimide molecule is successfully achieved, facilitated by the steric hindrance effect. Therefore, a new series of shape memory bismaleimide materials are obtained. By introducing a diamine to adjust the chain length, the properties of material are further improved, resulting in increasing static modulus by 506 times. The synthesized materials exhibit a broad glass transition temperature (Tg) range exceeding 153 °C, remarkable stiffness tunability. Notably, in the synthesis process of this materials series, the disulfide bonds are introduced, which facilitates the realization of self-healing and reprocessable functionalities in the resulting thermosetting materials. This significant advancement lays a solid foundation for the future recycling and reuse of aircraft, satellites, and other equipment, offering promising prospects for enhancing sustainability and efficiency within the aerospace industry.

Risk factor analysis of distant metastases in patients with primary medullary thyroid cancer: a population-based study.

OBJECTIVE: Medullary thyroid carcinoma has a high rate of recurrence and distant metastasis. The aim of this study was to investigate the risk factors for distant metastasis in patients with primary medullary thyroid carcinoma. METHODS: Patients diagnosed with primary medullary thyroid cancer between 2010 and 2015 were enrolled using the Surveillance, Epidemiology, and End Results (SEER) database. Patient demographics and tumor clinicopathological features were evaluated to identify potential risk factors for distant metastasis in patients with primary medullary thyroid cancer. Univariate and multivariate logistic regression analyses were used to determine independent risk factors for distant metastasis in patients with primary medullary thyroid carcinoma. All statistical analyses were performed using SPSS statistical software (version 27.0). A two-tailed P < 0.05 was considered statistically significant. RESULTS: We collected 685 patients with primary medullary thyroid carcinoma, 40 of whom (5.84%) developed distant metastases. Univariate logistic regression analysis showed that except marital status, age, sex, race, pT stage, N stage, multifocal and capsular infiltration were significantly correlated with distant metastasis of medullary thyroid carcinoma. Multivariate logistic regression analysis showed that patients aged ≤ 18 years or > 55 years, Black race, higher pT stage and N stage were independent risk factors for distant metastasis of medullary thyroid carcinoma. CONCLUSIONS: This study found that ≤ 18 years or > 55 years, black race, higher pT stage and N stage were significantly associated with distant metastasis of medullary thyroid cancer. This is important for clinicians to identify patients at high risk of distant metastasis in a timely manner.

Risk factors for cervical lymph node metastasis in the central or lateral cervical region in medullary thyroid carcinoma: a systematic review and meta-analysis.

PURPOSE: Compared with other types of thyroid carcinoma, patients with medullary thyroid carcinoma (MTC) are more likely to develop cervical lymph node metastasis. This study was conducted to clarify the risk factors for cervical lymph node metastasis (central lymph node metastasis or lateral cervical lymph node metastasis) in MTC by meta-analysis, and to provide evidence-based basis for the treatment and prognosis of MTC. METHODS: The literatures related to cervical lymph node metastasis in medullary thyroid carcinoma were searched in PubMed, Embase, Web of Science, Cochrane, CNKI and Wanfang databases, and statistical analysis was performed using Revman 5.3 and Stata 14.0 software. RESULTS: A total of 28 papers were included in this paper, and meta-analysis showed that the occurrence of central lymph node metastasis (CLNM) in MTC patients was significantly associated with tumor size (OR = 3.07, 95%CI: 2.04-4.63, P < 0.00001), multifocality (OR = 0.29, 95%CI: 0.19-0.44, P < 0.00001), bilaterality (OR = 3.75, 95% CI: 1.95-7.14, P < 0.0001), capsular invasion (OR = 9.88, 95% CI: 5.93-16.45, P < 0.00001) and extrathyroidal extension (OR = 5.48, 95% CI: 2.61-11.51, P < 0.00001). While the occurrence of lateral cervical lymph node metastasis (LLNM) in MTC patients was strongly correlated with gender (OR = 2.97, 95%CI: 2.46-3.58, P < 0.00001), tumor size (OR = 3.88, 95%CI: 1.90-7.92, P = 0.0002 < 0.05), multifocality (OR = 0.43, 95%CI: 0.35-0.51, P < 0.00001), bilaterality (OR = 2.93, 95% CI: 1.72-4.98, P < 0.0001), capsular invasion (OR = 8.44, 95% CI: 6.11-11.64, P < 0.00001), extrathyroidal extension (OR = 7.04, 95% CI: 5.54-8.94, P < 0.00001), margin of the tumor (OR = 4.47, 95% CI: 2.37-8.44, P < 0.00001), shape of the tumor (OR = 6.81, 95% CI: 3.64-12.73, P < 0.00001), preoperative calcitonin level (SMD = 1.39, 95% CI: 0.98-1.80, P < 0.00001), preoperative carcinoembryonic antigen level (SMD = 0.97, 95% CI: 0.74-1.20, P < 0.00001) and CLNM (OR = 19.70, 95% CI: 14.16-27.43, P < 0.00001). CONCLUSION: Tumor size, multifocality, bilaterality, capsular invasion and extrathyroidal extension are the main risk factors for developing CLNM in MTC patients; And risk factors for developing LLNM in MTC patients include: gender, tumor size, multifocality, bilaterality, capsular invasion, extrathyroidal extension, margin of the tumor, shape of the tumor, preoperative calcitonin level, preoperative carcinoembryonic antigen level and central lymph node metastasis. These risk factors can guide the individualized treatment plan and improve the prognosis of MTC patients.

Continuous straw returning enhances the carbon sequestration potential of soil aggregates by altering the quality and stability of organic carbon.

Soil structure plays an important role in organic carbon (OC) sequestration, thereby influencing soil fertility and changes in global climate. However, aggregate OC chemical structure changes due to long-term return of straw in oasis farmland of arid northwest China remains unclear. This study conducted 0-, 5-, 10-, 15-, and 20-year straw returning experiments during which three soil components where measured: (1) the functional carbon (C) pool and macroaggregates; (2) microaggregates and silt + clay; (3) the chemical structure of soil OC (SOC). The results demonstrated that in comparison with the control, straw return increased SOC, particulate OC (POC), and mineral-associated OC (MAOC) by 21.90%-63.51%, 5.00%-31.00%, and 46.00%-226.00%, respectively. With increasing duration of straw return, microaggregates transitioned to macroaggregates, and percentages of soil macroaggregates under 10-year straw return increased by 20.26%, 3.39%, 4.40%, and 11.12% compared with that under 0-, 5-, 15- and 20-year straw return, respectively. Soil geometric mean diameter (GMD) and mean weight diameter (MWD) first increased and then decreased, with maximum values after 10-year straw return at 1.20 mm and 1.63 mm, respectively. Solid state 13C NMR (Nuclear Magnetic Resonance) indicated O-alkyl C to be the dominant chemical component of soil OC over different years of straw return. There were increases in aromatic C, aromaticity, and hydrophobicity up to 10-year straw return, after which they decreased. A mantel test confirmed positive correlations of the distributions of macroaggregates, microaggregates, OC of macroaggregates, and silt + clay with MWD and GMD, whereas the OC content of aggregates was positively correlated with O-OA and hydrophobicity. Long-term straw returns improved soil structure and stabilized soil OC, thereby facilitating soil sequestration of OC.

Functional Peroral Infectivity Complex of White Spot Syndrome Virus of Shrimp.

White spot syndrome virus (WSSV) is a major cause of disease in shrimp cultures worldwide. The infection process of this large circular double-stranded DNA virus has been well studied, but its entry mechanism remains controversial. The major virion envelope protein VP28 has been implicated in oral and systemic viral infection in shrimp. However, genetic analysis of viral DNA has shown the presence of a few genes related to proteins of per os infectivity factor (PIF) complex in baculoviruses. This complex is essential for the entry of baculoviruses, large terrestrial circular DNA viruses, into the midgut epithelial cells of insect larvae. In this study, we aimed to determine whether a PIF complex exists in WSSV, the components of this complex, whether it functions as an oral infectivity complex in shrimp, and the biochemical properties that contribute to its function in a marine environment. The results revealed a WSSV PIF complex (~720 kDa) comprising at least eight proteins, four of which were not identified as PIF homologs: WSV134, VP124 (WSV216), WSSV021, and WSV136. WSV134 is suggested to be a PIF4 homolog due to predicted structural similarity and amino acid sequence identity. The WSSV PIF complex is resistant to alkali, proteolysis, and high salt, properties that are important for maintaining infectivity in aquatic environments. Oral infection can be neutralized by PIF-specific antibodies but not by VP28-specific antibodies. These results indicate that the WSSV PIF complex is critical for WSSV entry into shrimp; the complex's evolutionary significance is also discussed. IMPORTANCE White spot disease, caused by the white spot syndrome virus (WSSV), is a major scourge in cultured shrimp production facilities worldwide. This disease is only effectively controlled by sanitation. Intervention strategies are urgently needed but are limited by a lack of appropriate targets. Our identification of a per os infectivity factor (PIF) complex, which is pivotal for the entry of WSSV into shrimp, could provide new targets for antibody- or dsRNA-based intervention strategies. In addition, the presence of a PIF complex with at least eight components in WSSV, which is ancestrally related to the PIF complex of invertebrate baculoviruses, suggests that this complex is structurally and functionally conserved in disparate virus taxa.

Nanog safeguards early embryogenesis against global activation of maternal ß-catenin activity by interfering with TCF factors.

Maternal ß-catenin activity is essential and critical for dorsal induction and its dorsal activation has been thoroughly studied. However, how the maternal ß-catenin activity is suppressed in the nondorsal cells remains poorly understood. Nanog is known to play a central role for maintenance of the pluripotency and maternal -zygotic transition (MZT). Here, we reveal a novel role of Nanog as a strong repressor of maternal ß-catenin signaling to safeguard the embryo against hyperactivation of maternal ß-catenin activity and hyperdorsalization. In zebrafish, knockdown of nanog at different levels led to either posteriorization or dorsalization, mimicking zygotic or maternal activation of Wnt/ß-catenin activities, and the maternal zygotic mutant of nanog (MZnanog) showed strong activation of maternal ß-catenin activity and hyperdorsalization. Although a constitutive activator-type Nanog (Vp16-Nanog, lacking the N terminal) perfectly rescued the MZT defects of MZnanog, it did not rescue the phenotypes resulting from ß-catenin signaling activation. Mechanistically, the N terminal of Nanog directly interacts with T-cell factor (TCF) and interferes with the binding of ß-catenin to TCF, thereby attenuating the transcriptional activity of ß-catenin. Therefore, our study establishes a novel role for Nanog in repressing maternal ß-catenin activity and demonstrates a transcriptional switch between ß-catenin/TCF and Nanog/TCF complexes, which safeguards the embryo from global activation of maternal ß-catenin activity.

Inoculation of wheat with Bacillus sp. wp-6 altered amino acid and flavonoid metabolism and promoted plant growth.

KEY MESSAGE: Inoculation of wheat seedling with Bacillus sp. wp-6 changed amino acid metabolism and flavonoid synthesis and promoted plant growth. Plant growth-promoting rhizobacteria (PGPR), which can reduce the use of agrochemicals, is vital for the development of sustainable agriculture. In this study, proteomics and metabolomics analyses were performed to investigate the effects of inoculation with a PGPR, Bacillus sp. wp-6, on wheat (Triticum aestivum L.) seedling growth. The results showed that inoculation with Bacillus sp. wp-6 increased shoot and root fresh weights by 19% and 18%, respectively, after 40 days. The expression levels of alpha-linolenic acid metabolism-related proteins and metabolites (lipoxygenase 2, allene oxide synthase 2, jasmonic acid, 17-hydroxylinolenic acid) and flavonoid biosynthesis-related proteins and metabolites (chalcone synthase 2 and PHC 4'-O-glucoside) were up-regulated. In addition, the expression levels of amino acid metabolism-related proteins (NADH-dependent glutamate synthase, bifunctional aspartokinase/homoserine, anthranilate synthase alpha subunit 1, and 3-phosphoshikimate 1-carboxyvinyltransferase) and metabolites (L-aspartate, L-arginine, and S-glutathionyl-L-cysteine) were also significantly up-regulated. Among them, NADH-dependent glutamate synthase and bifunctional aspartokinase/homoserine could act as regulators of nitrogen metabolism. Overall, inoculation of wheat with Bacillus sp. wp-6 altered alpha-linolenic acid metabolism, amino acid metabolism, and flavonoid synthesis and promoted wheat seedling growth. This study will deepen our understanding of the mechanism by which Bacillus sp. wp-6 promotes wheat growth using proteomics and metabolomics.

Construction and validation of a nomogram for predicting cervical lymph node metastasis in diffuse sclerosing variant of papillary thyroid carcinoma.

OBJECTIVE: To analyze the risk factors associated with the occurrence of cervical lymph node metastasis (LNM) in patients with diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC) and to establish a nomogram model. METHODS: Clinical data of 199 DSV-PTC patients from SEER database were obtained, and they were randomly divided into training group (n=139) and validation group (n=60). The clinicopathological characteristics were analyzed by logistic regression, including age, marital status, race, gender, tumor size(cm), T stage, M stage, bilaterality, capsular invasion, extrathyroidal extension (ETE), and multifocality. The Validation was carried out using C-index, calibration curves, and Decision Curve Analysis (DCA) in terms of differentiation and calibration of the nomogram model, respectively. RESULTS: Age, tumor size(cm), capsular invasion, and multifocality were independent risk factors for the development of LNM in patients with DSV-PTC (P<0.05). In the training and validation groups, the C-index of internal validation of the nomogram was 0.808 (95%CI: 0.733-0.755) and 0.813 (95% CI: 0.591-0.868), the calibration curves showed that the model was in good agreement, and the decision curve (DCA) indicated that the nomogram model had good clinical utility.  CONCLUSION: Age, tumor size(cm), capsular invasion, and multifocality are independent risk factors for the development of LNM in DSV-PTC. The nomogram model can predict the risk of developing LNM in DSV-PTC patients and provide clinical guidance.

Comparison of mothers' perceptions of hunger cues in 3-month-old infant under different feeding methods.

BACKGROUND: Mothers' perception of infant hunger cues is a critical content of responsive feeding, which is central to the promotion of early childhood development. However, only a few studies have examined responsive feeding in China, especially lacking the studies on perceptions of infant hunger cues. Consider the cultural differences, the aim of this study was to describe the perceptions of infant hunger cues of Chinese mothers for infants aged 3 months, and explore the relationship between maternal perceptions of infant hunger cues and different feeding methods. METHODS: A cross-sectional study was conducted with a sample of 326 mothers of healthy 3-month-old infants, including 188 exclusive breastfeeding (EBF) mothers and 138 formula feeding (FF) mothers. It was implemented in four provincial and municipal maternal and child health hospitals. The mothers' perceptions of infant hunger cues were surveyed by self-reporting questionnaires. Chi-square tests and logistic analysis were applied to analyze the differences in maternal perceptions of infant hunger cues, including the number of hunger cues and the specific cues, between EBF group and FF group by controlling sociodemographic variables and the daily nursing indicators. RESULTS: We found that a higher proportion of EBF mothers could perceive multiple hunger cues (≥ 2) than FF mothers (66.5% vs.55.1%). For specific cues, the EBF mothers had higher perceptions of infant's "hand sucking" (67.6% vs. 53.6%) and "moving head frantically from side to side" (34.6% vs. 23.9%), all p < 0.05. Regression analysis revealed that EBF might support mothers to perceive infant hunger cues than FF mothers, with the number of infant hunger cues (OR = 1.70, 95% CI: 1.01-2.85), "hand sucking" (OR = 1.72, 95% CI: 1.04-2.87), "moving head frantically from side to side" (OR = 2.07, 95% CI: 1.19-3.62). The number of infant hunger cues perceived by mothers was also associated with their educational level and family structure. CONCLUSION: EBF mothers of 3-month-old infants may be more likely to perceive infant hunger cues than FF mothers in China. It is necessary to increase the health education about infant hunger and satiety cues to caregivers in China, especially among mothers with lower education levels, mothers living in nuclear families, and FF mothers.

Clinicopathological features and prognostic value of CD276 expression in head and neck cancer: A meta-analysis.

OBJECTIVE: We conducted a meta-analysis to assess the predictive value of CD276 expression in the clinicopathological features and prognosis of head and neck cancer. METHODS: Pubmed, Embase, Cochrane library, Web of science, CNKI and Wanfang databases were searched for studies focused on the role of CD276 expression in the clinicopathological features and prognosis of head and neck cancer, published up to December 2022. STATA 14.0 were used to perform the meta-analysis. RESULTS: A total of 8 eligible studies involving 1417 patients with head and neck cancer were included in this meta-analysis. The results showed that in terms of clinicopathological features, CD276 expression was related to gender [OR = 1.35, 95%CI = 1.01-1.82, P = 0.04], lymph node status [OR = 3.43, 95%CI = 1.96-5.98, P < 0.001] and TNM stage [OR = 2.54, 95%CI = 1.72-3.74, P < 0.001] of head and neck cancer patients, but not age [OR = 0.76, 95%CI = 0.52-1.11, P = 0.15] and tumor differentiation [OR = 1.39, 95%CI = 0.92-2.13, P = 0.12] . In terms of prognosis, CD276 expression is significantly associated with shorter overall survival [HR = 2.08, 95%CI = 1.22-3.56, P = 0.01] in head and neck cancer patients. CONCLUSION: CD276 expression was significantly correlated with gender, lymph node status, TNM stage and poor prognosis in head and neck cancer patients and may be a new target for immunotherapy and a biomarker for predicting poor prognosis in head and neck cancer.

Physiological, proteomic, and metabolomic analysis provide insights into Bacillus sp.-mediated salt tolerance in wheat.

KEY MESSAGE: Herein, the inoculation with strain wp-6 promoted the growth of wheat seedlings by improving the energy production and conversion of wheat seedlings and alleviating salt stress. Soil salinization decreases crop productivity due to high toxicity of sodium ions to plants. Plant growth-promoting rhizobacteria (PGPR) have been demonstrated to alleviate salinity stress. However, the mechanism of PGPR in improving plant salt tolerance remains unclear. In this study, physiological analysis, proteomics, and metabolomics were applied to investigate the changes in wheat seedlings under salt stress (150 mM NaCl), both with and without plant root inoculation with wp-6 (Bacillus sp.). Under salt stress, root inoculation with strain wp-6 increased plant biomass (57%) and root length (25%). The Na+ content was reduced, while the K+ content and K+/Na+ ratio were increased. The content of malondialdehyde was decreased by 31.94% after inoculation of wp-6 under salt stress, while the content of proline, soluble sugar, and soluble protein were increased by 7.48%, 12.34%, and 4.12%, respectively. The peroxidase, catalase, and superoxide dismutase activities were increased after inoculation of wp-6 under salt stress. Galactose metabolism, phenylalanine metabolism, caffeine metabolism, ubiquinone and other terpenoid-quinone biosynthesis, and glutathione metabolism might play an important role in promoting the growth of salt-stressed wheat seedlings after the inoculation with wp-6. Interaction analysis of differentially expressed proteins and metabolites found that energy production and transformation-related proteins and six metabolites (D-arginine, palmitoleic acid, chlorophyllide b, rutin, pheophorbide a, and vanillylamine) were mainly involved in the growth of wheat seedlings after the inoculation with wp-6 under salt stress. Furthermore, correlation analysis found that inoculation with wp-6 promotes the growth of salt-stressed wheat seedlings mainly through regulating amino acid metabolism and porphyrin and chlorophyll metabolism. This study provides an eco-friendly method to increase agricultural productivity and paves a way to sustainable agriculture.

Catalytic Enantioconvergent Allenylation of Aldehydes with Propargyl Halides.

α-Allenol is a versatile synthon in organic synthesis. The catalytic asymmetric synthesis of α-allenols from readily available starting materials remains a prominent challenge, especially when simultaneous control over axial and central chirality is required. Herein, we describe the Cr-catalyzed enantioconvergent allenylation of aldehydes with racemic propargyl halides to rapidly access a wide range of chiral α-allenols with adjacent axial and central chiralities. This method features excellent regio-, diastereo- and enantioselectivity control with broad substrate scope, and provides facile access to all four stereoisomers when allied with a Mitsunobu reaction. Preliminary mechanistic studies support radical-based reaction pathways. The synthetic utility is demonstrated by the application in late-stage functionalization and the formal total synthesis of (+)-varitriol.

Functional Droplets Stabilized by Interfacially Self-Assembled Chiral Nanocomposites.

Here, we show that aqueous dispersions of inorganic nanoparticles bearing negative surface charges would trigger the chiral assembly of organic radical cations solubilized in organic solvent at the liquid-liquid interface, which consequently produces stable droplets covered by a layer of inorganic/organic chiral nanocomposites. We demonstrate that chirality transfer across the liquid-liquid interface from the chiral organic monomers to the nanoparticle assemblies is realized. Surprisingly, opposite handedness between molecular assemblies and nanoparticle assemblies is determined from both CD and CPL measurements. Moreover, the functionalities of these "chiral" droplets could be further engineered through either a simple mixing or a droplet merging strategy, which enables to produce fluorescent emissive-tunable, magnetic, as well as magnetofluorescent dual-functional droplets.

Diversifying Nanoparticle Superstructures and Functions Enabled by Translative Templating from Supramolecular Polymerization.

Biology exploits a transcription-translation approach to deliver structural information from DNA to the protein-building machines with high precision. Here, we show how the structural information of small synthetic molecules could be used to guide the assembly of inorganic nanoparticles into diversified yet long-range ordered superstructures, enabling the information transfer across four or five orders of magnitude in length scale. We designed three perylene diimide (PDI) based isomers differing by their site-specific substitutions of the methyl group, which were able to supramolecularly polymerize into diverse structures. Importantly, coassembly of these PDI isomers with nanoparticles (NPs) could produce diverse long-range ordered nanoparticle superstructures, including one-dimensional NPs chains, double helical NPs assemblies and two-dimensional NPs superlattices. Equally important, we demonstrate that the information originated from small molecules could diversify the functions of the self-assembled nanocomposites.

Chirality Inversion in Self-Assembled Nanocomposites Directed by Curvature-Mediated Interactions.

Nanoscale curvature-dependent interactions are of paramount importance in biological systems. Here, we report that nanoscale curvature plays an important role in regulating the chirality of self-assembled nanocomposites from chiral organic molecules and achiral nanoparticles. Specifically, we show that the supramolecular chirality of the nanocomposites markedly depends on the nanoparticle curvature, where small-sized nanoparticles of high curvature and large-sized nanoparticles of low curvature lead to nanocomposites with opposite chirality. Quantitative kinetic experiments and molecular dynamics simulations reveal that nanoparticle curvature plays a key role in promoting the pre-nucleation oligomerization of chiral molecules, which consequently regulates the supramolecular chirality of the nanocomposites. We anticipate that this study will aid in rational design of an artificial cooperative system giving rise to emergent assembling phenomena that can be surprisingly rich and often cannot be understood by studying the conventional noncooperative systems.

Self-Assembled Open Porous Nanoparticle Superstructures.

Imparting porosity to inorganic nanoparticle assemblies to build up self-assembled open porous nanoparticle superstructures represents one of the most challenging issues and will reshape the property and application scope of traditional inorganic nanoparticle solids. Herein, we discovered how to engineer open pores into diverse ordered nanoparticle superstructures via their inclusion-induced assembly within 1D nanotubes, akin to the molecular host-guest complexation. The open porous structure of self-assembled composites is generated from nonclose-packing of nanoparticles in 1D confined space. Tuning the size ratios of the tube-to-nanoparticle enables the structural modulation of these porous nanoparticle superstructures, with symmetries such as C1, zigzag, C2, C4, and C5. Moreover, when the internal surface of the nanotubes is blocked by molecular additives, the nanoparticles would switch their assembly pathway and self-assemble on the external surface of the nanotubes without the formation of porous nanoparticle assemblies. We also show that the open porous nanoparticle superstructures can be ideal candidate for catalysis with accelerated reaction rates.

CdSe 1D/2D Mixed-Dimensional Heterostructures: Curvature-Complementary Self-Assembly for Enhanced Visible-Light Photocatalysis.

Mixed-dimensional heterostructures (MDHs), which combine nanomaterials of different dimensionalities deliver on the promise to bypass intrinsic limitations of a given low-dimensional material. Here, a strategy to engineer MDHs between two low-dimensional materials by curvature-complementary self-assembly is described. CdSe nanotubes rolled from 2D nanosheets and 1D CdSe nanorods, with negative and positive curvatures, respectively, are selected to illustrate complementary curvature self-assembly. The assembly process, optical, and photoelectrical properties of the CdSe MDHs are thoroughly investigated. Several remarkable features of CdSe MDHs, including increased light absorption, efficient charge separation, and appropriate bandgap structure are confirmed. The MDHs significantly alleviate the sluggish kinetics of electron transfer in the quantum sized CdSe subunits (onset potential of 0.21 V vs RHE for MDHs; 0.4 V lower than their low-dimensional building blocks), while the spatial nano-confinement effect in the CdSe MDHs also assists the interfacial reaction kinetics to render them ideal photocatalysts for benzylamine oxidation (conversion > 99% in 4 h with a two times higher rate than simple mixtures). The results highlight opportunities for building MDHs from low-dimensional building blocks with curvature-complementary features and expand the application spectrum of low dimensional materials in artificial photosynthesis.

Efficacy of 5-Aminolevulinic Acid (ALA)-Photodynamic Therapy (PDT) in Refractory Vulvar Lichen Sclerosus: Preliminary Results.

BACKGROUND As a chronic inflammatory skin disease of unknown etiology, vulvar lichen sclerosus (VLS) mainly affects postmenopausal and perimenopausal women. The main clinical manifestations of VLS include itching, burning pain, and sexual dysfunction, which can lead to a decline in quality of life. The existing treatment options include topical corticosteroid ointment, estrogen, and traditional Chinese medicine; however, their therapeutic effects on VLS remain unsatisfactory. MATERIAL AND METHODS Thirty patients with VLS and routine treatment failure were treated with 5-aminolevulinic acid (ALA)-photodynamic therapy (PDT). A 20% ALA water-in-oil emulsion was applied to the vulvar lesions and sealed with plastic film for 3 h. Patients were irradiated at a power density of 60 to 90 mW/cm² with a red light at a wavelength of 635±15 nm for 20 min, delivering a total dose of 100 to 150 J/cm² per session. The treatment was repeated 3 times every 2 weeks. The objective parameters, female sexual function index (FSFI) and quality of life (QoL) scores, were used before and after treatment to evaluate the clinical curative effect. RESULTS All patients completed 3 treatment cycles of ALA-PDT and follow-up visits. The clinical symptoms of pruritus completely disappeared in 27 cases, and itching improved from severe to mild in 3 cases. The pathological changes of all patients were objectively improved. FSFI score decreased significantly after treatment (P<0.001). The main adverse effects of ALA-PDT were pain, erythema, and swelling. These adverse effects were temporary and tolerable. The QoL score was significantly improved after treatment (P<0.001). CONCLUSIONS ALA-PDT is an effective and safe approach for the treatment of VLS.