bluuebunny/crossref_metadata_2025 huggingface dataset:
Unraveling the Tandem Effect of Nitrogen Configuration Promoting Oxygen Reduction Reaction in Alkaline Seawater
Authors: Wu Siqi , Liu Xiaobin , Mao Huimin , Zhu Jiawei , Zhou Guizhong , Chi Jingqi , Wu Zexing , Wang Lei
Published: April 2024

Developing seawater‐based high‐performance oxygen reduction reaction (ORR) electrocatalysts is meaningful to renewable energy storage and conversion, and the Fe‐based derivatives encapsulated by nitrogen (N) doped carbon are the typical representative. Nevertheless, unrevealing the mechanism of N configuration to ORR activity and chlorine resistance is still a great challenge. In this work, a feasible strategy is developed to prepare controllable pyridinic/pyrrolic‐N doped carbon‐coated Fe‐based electrocatalysts (FexN‐NC). Drawing support from the H3PO4 blocking based in situ Fourier transform infrared spectroscopy (FTIR) test and density‐functional theory (DFT) calculation, the tandem effect of pyridinic‐N and pyrrolic‐N on ORR is proved. Additionally, the low hydrogen peroxide (H2O2) yield and 4e− pathway of FexN‐NC demonstrate that N doping effectively reduces the adsorption of Cl−, which is consistent with the low Cl− adsorption energy of DFT. The half‐wave potential (E1/2) of FexN‐NC for ORR reaches 0.874 V in alkaline seawater, and ZABs assembled with FexN‐NC as the air cathode deliver a remarkable power density (162 mW cm−2), along with excellent long‐term durability (>400 h).
Protective and Collision‐Sensitive Gel‐Skin: Visco‐Elastomeric Polyvinyl Chloride Gel Rapidly Detects Robot Collision by Breaking Electrical Charge Accumulation Stability
Authors: Hwang Geonwoo , Nam Jongseok , Kim Minki , Diaz Cortes David Santiago , Kyung Ki‐Uk
Published: April 2024

Human–robot collaboration (HRC) is effective to improve productivity in industrial fields, based on the robot's fast and precise work and the human's flexible skill. To facilitate the HRC system, the first priority is to ensure safety in the event of accidents, such as collisions between robots and humans. Therefore, a protective and collision‐sensitive robot skin, named Gel‐Skin is proposed to guarantee the safety in HRC. The Gel‐Skin is composed of polyvinyl chloride (PVC) gel, which is a functional material with piezoresistive characteristics and impact absorption capability. In particular, the PVC gel has a distinctive piezoresistive property that the relation between mechanical pressure and electrical resistance is tunable depending on an applied voltage. When a voltage is applied to the PVC gel, the electrical charges are accumulated around the anode and it shows increased piezoresistive sensitivity. In this study, it is verified for the PVC gel to exhibit the 4.78 times higher sensitivity by simply applying a voltage. This novel physical phenomenon enables the Gel‐Skin to detect the collision rapidly. Finally, the Gel‐Skin is applicated to a real robot system and it is verified that the Gel‐Skin can detect a collision and absorb impact to ensure safety.
A Resampling Ant Colony Optimization with Elite Exploration and Convergence Mechanism for Multithreshold Segmentation of Breast Cancer Images
Authors: Wang Zhen , Zhao Dong , Heidari Ali Asghar , Chen Yi , Chen Huiling , Liang Guoxi
Published: April 2024

Previous studies have emphasized the potential of threshold image segmentation for early breast cancer detection. However, traditional methods encounter challenges regarding low segmentation efficiency and accuracy. Addressing this, the ant colony optimization algorithm for continuous optimization (ACOR) shows promise. Yet, existing ACOR variants still grapple with poor initial population quality, affecting convergence speed and avoiding local optimization. These issues impact segmentation efficiency and accuracy. To tackle them, this study introduces RESACO, an enhanced ACOR version integrating three novel optimization strategies: resampling initialization (RIS), elite exploration (EES), and strengthened convergence mechanism (SCM). RIS enhances initial population quality by resampling regions with individuals demonstrating superior fitness and segmentation efficiency. EES promotes exploration across the search space, preventing local optima entrapment and enhancing model stability. SCM expediting convergence, segmentation efficiency, and precision. RESACO's performance is assessed through extensive experiments using IEEE CEC 2014 and IEEE CEC 2022 benchmark functions, including ablation experiments and comparisons with basic and improved algorithms and ACOR variants. Subsequently, the threshold image segmentation model based on RESACO is compared with other models using metaheuristic algorithms for segmenting realistic breast cancer medical images. Results demonstrate the proposed model's faster convergence and higher segmentation accuracy, preserving more lesion tissue details.
Ocular manifestations of CHARGE syndrome in a pediatric cohort with genotype/phenotype analysis
Authors: Kanwar Kunal , Bashey Saffiya , Bohnsack Brenda L. , Drackley Andy , Ing Alexander , Rahmani Safa , Ranaivo Hantamalala Ralay , McMullen Patrick , Skol Andrew , Yap Kailee , Allegretti Valerie , Rossen Jennifer L.
Published: April 2024

CHARGE syndrome is a rare multi‐system condition associated with CHD7 variants. However, ocular manifestations and particularly ophthalmic genotype–phenotype associations, are not well‐studied. This study evaluated ocular manifestations and genotype–phenotype associations in pediatric patients with CHARGE syndrome. A retrospective chart review included pediatric patients under 20 years‐old with clinical diagnosis of CHARGE syndrome and documented ophthalmic examination. Demographics, genetic testing, and ocular findings were collected. Comprehensive literature review enhanced the genotype–phenotype analysis. Forty‐two patients (20 male) underwent eye examination at an average age of 9.45 ± 6.52 years‐old. Thirty‐nine (93%) had ophthalmic manifestations in at least one eye. Optic nerve/chorioretinal colobomas were most common (38 patients), followed by microphthalmia (13), cataract (6), and iris colobomas (4). Extraocular findings included strabismus (32 patients), nasolacrimal duct obstructions (11, 5 with punctal agenesis), and cranial nerve VII palsy (10). Genotype–phenotype analyses (27 patients) showed variability in ocular phenotypes without association to location or variant types. Splicing (10 patients) and frameshift (10) variants were most prevalent. Patients with CHARGE syndrome may present with a myriad of ophthalmic manifestations. There is limited data regarding genotype–phenotype correlations and additional studies are needed.
Methanesulfonic Acid‐Catalyzed Friedel‐Crafts Alkylation: Towards Sustainable Synthesis of Arylalkanes from Donor–Acceptor Cyclopropane Ketones
Authors: Goswami Lakshmi , Paul Sayantan , Mamale Ajay G. , Gonnade Rajesh G. , Bhattacharya Asish K.
Published: April 2024

We present herein Brønsted acid‐catalyzed Friedel‐Crafts alkylation of phenols with Donor–Acceptor cyclopropane ketones. The presence of the 1,4‐diphenyl butan‐1‐one and 1,3‐diphenyl propane‐1‐one motifs in various naturally occurring biologically significant molecules inspired us to pursue the direct synthesis of these structural frameworks. Utilizing methanesulfonic acid (MeSO3H) as a catalyst, we achieved a more environmentally friendly and high‐yielding synthesis, owing to its cost‐effectiveness, biodegradability, transition–metal and additives free conditions. Furthermore, we have successfully extended our developed methodology to thiophenols, resulting in the production of sulfur–based butan‐1‐one derivatives in good yields.
Racial discrimination during middle age predicts higher serum phosphorylated tau and neurofilament light chain levels a decade later: A study of aging black Americans
Authors: Simons Ronald L. , Ong Mei Ling , Lei Man‐Kit , Beach Steven R. H. , Zhang Yue , Philibert Robert , Mielke Michelle M.
Published: April 2024

INTRODUCTION

Recent evidence suggests that exposure to the stress of racism may increase the risk of dementia for Black Americans.

METHODS

The present study used 17 years of data from a sample of 255 Black Americans to investigate the extent to which exposure to racial discrimination predicts subsequent changes in serum Alzheimer's Disease Research Center (ADRC) biomarkers: serum phosphorylated tau181(p‐tau181), neurofilament light (NfL), and glial fibrillary acidic protein (GFAP). We hypothesized that racial discrimination assessed during middle age would predict increases in these serum biomarkers as the participants aged into their 60s.

RESULTS

Our findings indicate that exposure to various forms of racial discrimination during a person's 40s and early 50s predicts an 11‐year increase in both serum p‐tau181 and NfL. Racial discrimination was not associated with subsequent levels of GFAP.

DISCUSSION

These findings suggest that racial discrimination in midlife may contribute to increased AD pathology and neurodegeneration later in life.

Highlights

A 17‐year longitudinal study of Black Americans.

Assessments of change in serum p‐tau181, neurofilament light, and glial fibrillary acidic protein.

Exposure to racial discrimination during middle age predicted increases in p‐tau181 and neurofilament light.

Education was positively related to both p‐tau181 and exposure to racial discrimination.
Controllable Skeletal and Peripheral Editing of Pyrroles with Vinylcarbenes
Authors: Yang Yong , Song Qingmin , Sivaguru Paramasivam , Liu Zhaohong , Shi Dan , Tian Tian , de Ruiter Graham , Bi Xihe
Published: April 2024

The skeletal editing of azaarenes through insertion, deletion, or swapping of single atoms has recently gained considerable momentum in chemical synthesis. Here, we describe a practical skeletal editing strategy using vinylcarbenes in situ generated from trifluoromethyl vinyl N‐triftosylhydrazones, leading to the first dearomative skeletal editing of pyrroles through carbon‐atom insertion. Furthermore, depending on the used catalyst and substrate, three types of peripheral editing reactions of pyrroles are also disclosed: α‐ or γ‐selective C−H insertion, and [3+2] cycloaddition. These controllable molecular editing reactions provide a powerful platform for accessing medicinally relevant CF3‐containing N‐heterocyclic frameworks, such as 2,5‐dihydropyridines, piperidines, azabicyclo[3.3.0]octadienes, and allylated pyrroles from readily available pyrroles. Mechanistic insights from experiments and density functional theory (DFT) calculations shed light on the origin of substrate‐ or catalyst‐controlled chemo‐ and regioselectivity as well as the reaction mechanism.
An Artificial Enzyme for Asymmetric Nitrocyclopropanation of α,β‐Unsaturated Aldehydes—Design and Evolution
Authors: Yu Ming‐Zhu , Yuan Ye , Li Zhen‐Jie , Kunthic Thittaya , Wang He‐Xiang , Xu Chen , Xiang Zheng
Published: April 2024

The introduction of an abiological catalytic group into the binding pocket of a protein host allows for the expansion of enzyme chemistries. Here, we report the generation of an artificial enzyme by genetic encoding of a non‐canonical amino acid that contains a secondary amine side chain. The non‐canonical amino acid and the binding pocket function synergistically to catalyze the asymmetric nitrocyclopropanation of α,β‐unsaturated aldehydes by the iminium activation mechanism. The designer enzyme was evolved to an optimal variant that catalyzes the reaction at high conversions with high diastereo‐ and enantioselectivity. This work demonstrates the application of genetic code expansion in enzyme design and expands the scope of enzyme‐catalyzed abiological reactions.
Anisotropic Semicrystalline Homopolymer Dielectrics for High‐Temperature Capacitive Energy Storage
Authors: Xu Wenhan , Zhou Chenyi , Ji Wenhai , Zhang Yunhe , Jiang Zhenhua , Bertram Florian , Shang Yingshuang , Zhang Haibo , Shen Chen
Published: April 2024

High‐temperature dielectric polymers are in high demand for powering applications in extreme environments. Here, we have developed high‐temperature homopolymer dielectrics with anisotropy by leveraging the hierarchical structure in semicrystalline polymers. The lamellae have been aligned parallel to the surface in the dielectric films. This structural arrangement resembles the horizontal alignment of nanosheet fillers in polymer nanocomposites and nanosheet‐like lamellae in block copolymers, which has been proven to provide the optimal topological structure for electrical energy storage. The unique ordering of lamellae in our dielectric films endue a significantly increased breakdown strength and a reduced leakage current compared to amorphous films. This novel approach of enhancing the capacitive energy storage properties by controlled orientation of lamellae in homopolymer offers a new perspective for the design of high‐temperature polymer dielectrics.
Strategies for Achieving Ultra‐Long ORR Durability—Rh Activates Interatomic Interactions in Alloys
Authors: Li Xiaoke , Duan Xiao , Zhang Siao , Wang Chuanjie , Hua Kang , Wang Zejin , Wu Yongkang , Li Jia , Liu Jianguo
Published: April 2024

The stability of platinum‐based alloy catalysts is crucial for the future development of proton exchange membrane fuel cells, considering the potential dissolution of transition metals under complex operating conditions. Here, we report on a Rh‐doped Pt3Co alloy that exhibits strong interatomic interactions, thereby enhancing the durability of fuel cells. The Rh−Pt3Co/C catalyst demonstrates exceptional catalytic activity for oxygen reduction reactions (ORR) (1.31 A mgPt−1 at 0.9 V vs. the reversible hydrogen electrode (RHE) and maintaining 92 % of its mass activity after 170,000 potential cycles). Long‐term testing has shown direct inhibition of Co dissolution in Rh−Pt3Co/C. Furthermore, tests on proton exchange membrane fuel cells (PEMFC) have shown excellent performance and long‐term durability with low Pt loading. After 50,000 cycles, there was no voltage loss at 0.8 A cm−2 for Rh−Pt3Co/C, while Pt3Co/C experienced a loss of 200 mV. Theoretical calculations suggest that introducing transition metal atoms through doping creates a stronger compressive strain, which in turn leads to increased catalytic activity. Additionally, Rh doping increases the energy barrier for Co diffusion in the bulk phase, while also raising the vacancy formation energy of the surface Pt. This ensures the long‐term stability of the alloy over the course of the cycle.
Enhanced mechanical qualities of sericin‐removed silk by direct feeding of silkworms with cellulose nanofiber
Authors: Kobayashi Genki , Kurita Hiroki , Nagasawa Atsuhiko , Hori Masatoshi , Narita Fumio
Published: April 2024

Recently, the modification of silkworm silk fibers (SFs) by adding fillers has been investigated. Previously, we have reported that SFs obtained from silkworms fed diets supplemented with 5 wt.% cellulose nanofiber (CNF) and whose surface was covered with sericin exhibited excellent tensile properties. On the other hand, to use SF in silk products, the sericin must be removed, and it is necessary to ensure that CNF‐enriched silkworm SFs with the sericin removed (i.e., fibroin) exhibit high tensile properties. Therefore, this study evaluated the tensile properties of sericin‐removed SF obtained from silkworms fed a CNF diet. The results showed that the average CNF with SF—near 7.5 wt.% exhibited high mechanical properties. Adding CNF to the silkworm diet did not affect their growth and cocoon yield. The analysis of the SF microstructure confirmed that CNF is a fibrous material on the surface of fibroin. Kelly‐Tyson's equation suggested that almost all of the CNF in fibroin contributed to the increased tensile strength.
Flame retardant polyurethane microbubble elastomer based on ionic liquid/ammonium polyphosphate/aluminum hypophosphite ternary flame retardant system
Authors: Liu Kai , Gao Xingtong , Liu Zhiyuan , Hu Wenjin , Li Aixiang , Xu Yanjun , Zhang Wenjie
Published: April 2024

To develop a highly efficient flame retardant system for polyurethane microbubble elastomer (PME), a phosphate‐based ionic liquid (IL) 1‐methyl‐3‐(dioxyphosphoryl)‐propyl imidazole bromide was synthesized, and then combined with ammonium polyphosphate (APP) and aluminum hypophosphate (ALHP) to form a ternary flame retardant system, which shows excellent synergistic flame retardancy and plays an important role in both gas phase and condensed phase flame retardancy. Compared with pure PME, the limiting oxygen index of flame retardant PME with 6 wt% IL and 15 wt% APP/ALHP increased from 20.25% to 29.25%, the char yields is increased by 13 times, and the heat release rate, total heat release rate, mass loss rate, and smoke production rate are reduced by 74%, 19%, 67%, and 22%, respectively. Ignition time increased from 9 s to 19 s, and extinguishing time increased from 295 s to 573 s. At the same time, the addition of IL promoted the dispersion and compatibility of APP/ALHP in the PME matrix and improved the mechanical properties. In addition, IL also shows potential in antistatic modification, providing the possibility for materials to meet both flame retardant and antistatic requirements.
Effect of polyphenylene sulfide sulfone sizing agent on interfacial, thermal, and mechanical properties of carbon fiber
Authors: Zhuang Yifan , Liu Haibin , Zhou Shaoyang , Jia Zhehao , Sun Ying
Published: April 2024

Polyphenylene sulfide sulfone (PPSS) was synthesized by one‐step method and utilized as a sizing agent for carbon fibers. The effects of various monomer ratios, reaction time, and reaction temperature were investigated on the molecular weight of PPSS. The thermal analysis revealed that the product PPSS exhibited a glass transition temperature exceeding 215.5°C, indicating exceptional thermal stability. After PPSS sizing treatment, the grooves on the surface of carbon fibers were filled, resulting in a substantial enhancement of the microinterface properties. The surface energy was increased by 8.2%, while the maximum weight loss temperature was 27.8% higher than that of the commercial carbon fiber. The tensile strength of the carbon fiber after heat treatment reached 2196 MPa, representing a 45.9% increase over that of the commercial carbon fiber.
Ambient Temperature Metal‐Free Thiomethylation of Chloroheteroarenes and Chloropurines
Authors: Patel Manisha A. , Vora Raj K. , Sanghvi Yogesh S. , Kapdi Anant R.
Published: April 2024

Herein, we report an in‐situ mild and metal‐free protocol for thiomethylation of heteroarenes in high yields. The thiomethylation of various chloropurines, nucleosides, and chloroheteroarenes has been accomplished offering easy access to agrochemicals and synthetic molecules useful for drug discovery.
Novel definition of textbook outcome in biliary system cancers and its influence on patients' survival and quality of life
Authors: Atyah Manar Mikhail , Xu Li , Yang Zhiying
Published: April 2024

Background

The definition of textbook outcome in biliary system cancers is a developing concept in need of expansion and investigation of its association with survival and quality of life.

Methods

In this original research, we developed a novel “all or none” textbook outcome definition which addresses the rapid recovery of post‐surgical indexes, in addition to short‐term mortality, hospital re‐admission, prolonged stay, surgical margin and postoperative complications. Based on the fulfillment of relevant criteria, patients were divided into textbook outcome and non‐textbook outcome groups and their characteristics and survival data were analyzed. A customized “quality of life” questionnaire was developed to address short‐term recovery and post‐discharge life quality of patients. Association with quality of life improvement was then investigated.

Results

A total of 129 patients were included. Textbook outcome was achieved in 25.58% of patients (37.04% of gallbladder cancer patients and 17.8% of cholangiocarcinoma patients). Compared to non‐textbook outcome group, patients with textbook outcome had lower rate of pre‐operative biliary drainage (p = 0.026), higher rate of normal preoperative liver function (p < 0.001) and tumor markers (p = 0.001), reduced perioperative bleeding (p = 0.006) and blood transfusion (p = 0.005), and higher rate of N0 stage cases (p = 0.008). Textbook outcome was also associated with enhanced survival, significantly in older patients (<65 years) (1‐year survival rate: 100% vs. 78.57% (p = 0.108), 2‐year survival rate: 87.5% vs. 44% (p = 0.046)). Finally, textbook outcome was significantly associated with enhanced basic daily performance (p < 0.001), social life performance (p = 0.033), and personal evaluation (p < 0.001), and thus improved quality of life (p < 0.001).

Conclusions

The novel definition of textbook outcome was able to address the specific nature of recovery after resection of biliary system cancers. Expanding the scope of textbook outcome and addressing the influence on survival and quality of life provides a comprehensive concept able to reflect physical, psychological and functioning enhancements in patients recovery.
A Rhodanese‐Like Enzyme that Catalyzes Desulfination of Ergothioneine Sulfinic Acid
Authors: Nalivaiko Egor Y. , Seebeck Florian P.
Published: April 2024

Many actinobacterial species contain structural genes for iron‐dependent enzymes that consume ergothioneine by way of O2‐dependent dioxygenation. The resulting product ergothioneine sulfinic acid is stable under physiological conditions unless cleavage to sulfur dioxide and trimethyl histidine is catalyzed by a dedicated desulfinase. This report documents that two types of ergothioneine sulfinic desulfinases have evolved by convergent evolution. One type is related to metal‐dependent decarboxylases while the other belongs to the superfamily of rhodanese‐like enzymes. Pairs of ergothioneine dioxygenases (ETDO) and ergothioneine sulfinic acid desulfinase (ETSD) occur in thousands of sequenced actinobacteria, suggesting that oxidative ergothioneine degradation is a common activity in this phylum.
In‐Situ Investigations of Polyoxometalate‐Catalysed Biomass Oxidation to Formic Acid by Using Multinuclear High Resolution Flow NMR Spectroscopy
Authors: Krueger Jan‐Dominik H. , Poller Maximilian J. , Lyall Catherine , Lowe John , Hintermair Ulrich , Albert Jakob
Published: April 2024

Biomass valorisation over polyoxometalate‐based (POM) catalysts is a promising strategy for green and sustainable chemistry. In order to further improve such processes e. g. by using different additives, a better understanding of the chemical influence of various additives on the catalyst is paramount. The main objective of this study is to gain a deeper understanding of the effects caused by various additives on the catalytically active vanadium species in the selective aerobic oxidation of carbohydrates to formic acid (esters). After carefully choosing a suitable model system, the oxidation of glycolaldehyde using the heteropolyacid H5PV2Mo10O40 (HPA‐2) as a catalyst was studied in situ by Flow Nuclear magnetic resonance (FlowNMR) spectroscopy. These measurements allowed to identify the catalytically active isomer of the HPA‐2‐catalyst and to observe the influence of additives on the reaction kinetics in situ. These findings provide a good basis for further improving POM‐based catalytic aerobic oxidation of biomass.
A Fluorination Strategy and Low‐Acidity Anchoring Group in Self‐Assembled Molecules for Efficient and Stable Inverted Perovskite Solar Cells
Authors: Sun Xiaowen , Fan Hua , Xu Xiaowei , Li Gongqiang , Gu Xiaoyu , Luo Dou , Shan Chengwei , Yang Qiong , Dong Shixing , Miao Chunyang , Xie Zheng , Lu Gang , Wang Dong Hwan , Sun Ping‐Ping , Kyaw Aung Ko Ko
Published: April 2024

Herein, we synthesized two donor‐acceptor (D‐A) type small organic molecules with self‐assembly properties, namely MPA‐BT‐BA and MPA‐2FBT‐BA, both containing a low acidity anchoring group, benzoic acid. After systematically investigation, it is found that, with the fluorination, the MPA‐2FBT‐BA demonstrates a lower highest occupied molecular orbital (HOMO) energy level, higher hole mobility, higher hydrophobicity and stronger interaction with the perovskite layer than that of MPA‐BT‐BA. As a result, the device based‐on MPA‐2FBT‐BA displays a better crystallization and morphology of perovskite layer with larger grain size and less non‐radiative recombination. Consequently, the device using MPA‐2FBT‐BA as hole transport material achieved the power conversion efficiency (PCE) of 20.32 % and remarkable stability. After being kept in an N2 glove box for 116 days, the unsealed PSCs’ device retained 93 % of its initial PCE. Even exposed to air with a relative humidity range of 30±5 % for 43 days, its PCE remained above 91 % of its initial condition. This study highlights the vital importance of the fluorination strategy combined with a low acidity anchoring group in SAMs, offering a pathway to achieve efficient and stable PSCs.
Protocol: Interventions aimed at preventing out‐of‐home placement of children: A systematic review
Authors: Dalgaard Nina Thorup , Bondebjerg Anja , Bengtsen Elizabeth , Dietrichson Jens , Bach‐Mortensen Anders
Published: April 2024

This is the protocol for a Campbell systematic review. The objectives are as follows. The aim of the present review is to synthesize evidence on the effectiveness of interventions for at‐risk families aimed at preventing the out‐of‐home placement of children or increasing the likelihood that children are reunited with their birth families following temporary care arrangements. The review has two objectives: (1) To assess the effectiveness of interventions for at‐risk families with children aged between 0 and 17 years old on measures of out‐of‐home placement and on secondary outcomes. (2) To identify factors that modify intervention effectiveness (e.g., prior placements, parental risk factors such as substance abuse, mental health issues, age, minority status, child risk factors such as disabilities, age, and gender).
Chemical Derivatization Leads to the Discovery Of Novel Analogs of Azotochelin, a Natural Siderophore, as Promising Anticancer Agents
Authors: Karadkhelkar Nishant M. , Gupta Pranav , Barasa Leonard , Chilamakuri Rameswari , Hlordzi Christopher K. , Acharekar Nikita , Agarwal Saurabh , Chen Zhe‐Sheng , Yoganathan Sabesan
Published: April 2024

Siderophores are structurally unique medicinal natural products and exhibit considerable therapeutic potential. Herein, we report the design and synthesis of azotochelin, a natural siderophore, and an extensive library of azotochelin analogs and their anticancer properties. We modified the carboxylic acid and the aromatic ring of azotochelin using various chemical motifs. We evaluated the cytotoxicity of the compounds against six different cancer cell lines (KB‐3‐1, SNB‐19, MCF‐7, K‐562, SW‐620, and NCI−H460) and a non‐cancerous cell line (HEK‐293). Among the twenty compounds tested, the IC50 values of nine compounds (14, 32, 35–40, and 54) were between 0.7 and 2.0 μM against a lung cancer cell line (NCI−H460). Moreover, several compounds showed good cytotoxicity profile (IC50 <10 μM) against the tested cancer cell lines. The flow cytometry analysis showed that compounds 36 and 38 induced apoptosis in NCI−H460 in a dose‐dependent manner. The cell cycle analysis indicated that compounds 36 and 38 significantly arrested the cell cycle at the S phase to block cancer cell proliferation in the NCI−H460 cell line. The study has produced various novel azotochelin analogs that are potentially effective anticancer agents and lead compounds for further synthetic and medicinal chemistry exploration.
How the Milan System for Reporting Salivary Gland Cytopathology works in cytopathology practice: Meta‐analysis of prospective studies and comparison with retrospective studies
Authors: Lagerstam Henri , Kalfert David , Maleki Zahra , Kholová Ivana
Published: April 2024

Background

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is widely accepted and endorsed by professional societies. Although several studies focusing on the MSRSGC have been published, few have been prospective studies. The objective of this study was to evaluate the effectiveness of the MSRSGC in cytopathology practice.

Methods

A comprehensive literature search was conducted to identify all prospective studies on the MSRSGC. The risk of malignancy (ROM), risk of neoplasm, and diagnostic accuracy for each diagnostic category were calculated. Data were tabulated in Microsoft Excel, and analyses were performed with the Open Meta‐Analyst program.

Results

Seven prospective and seven retrospective studies were identified. The total number of fine‐needle aspirations (FNAs) was 1587 in the prospective studies and 1764 in the retrospective studies. The ROM values for the nondiagnostic, nonneoplastic, atypia of undetermined significance, benign neoplasm, salivary gland neoplasm of uncertain malignant potential, suspicious for malignancy, and malignant categories in prospective versus retrospective studies were 21.0% versus 26.6%, 9.4% versus 8.1%, 34.9% versus 39.6%, 2.4% versus 2.1%, 36.6% versus 31.2%, 86.0% versus 66.0%, and 97.0% versus 96.7%, respectively. Sensitivities, specificities, and diagnostic odds ratios were 83.1% (95% confidence interval [CI], 71.1%–90.8%) versus 89.1% (95% CI, 83.6%–92.9%), 98.4% (95% CI, 96.6%–99.3%) versus 94.9% (95% CI, 91.9%–96.9%), and 310.7 (95% CI, 121.2–796.6) versus 218.8 (95% CI, 107.3–438.1).

Conclusions

This meta‐analysis indicated that the MSRSGC works well in FNA cytopathology practice and improves diagnostic accuracy in all diagnostic categories. The ROMs of prospective studies were in concordance with the MSRSGC reference values.
Exploring the atypia of undetermined significance: Malignant ratio, ThyroSeq v3 positive call rate, molecular‐derived risk of malignancy, and risk of malignancy as possible quality metric tools in thyroid cytology
Authors: Velez Torres Jaylou M. , Curnow Porshya M. , Tjendra Youley , Jorda Merce , Fernandez Carmen Gomez , Buitrago Monica Garcia , Zuo Yiqin , Cordero Roberto Ruiz
Published: April 2024

Background

The atypia of undetermined significance (AUS) category is heterogeneous, leading to variations in its use. To prevent excessive usage, the AUS rate should be ≤10%. Although this recommendation aims to maintain diagnostic quality, it lacks supporting data. The AUS:Malignant (AUS:M) ratio has been proposed as a metric tool to evaluate AUS use. Furthermore, integrating ThyroSeq v3 (TSV3) positive call rate (PCR) and the molecular‐derived risk of malignancy (MDROM) have been put forward as performance improvement tools. The authors reviewed their AUS:M ratios, TSV3 PCR, MDROM, and ROM.

Methods

Thyroid aspirates evaluated in the laboratory (from August 2022 to September 2023) by seven cytopathologists (CPs) were identified. AUS:M ratio, MDROM, ROM, and TSV3 PCR results for the laboratory and each CP were recorded and analyzed.

Results

A total of 2248 aspirates were identified (462 AUS and 80 malignant). The AUS:M ratio for the laboratory was 5.8 (CPs range, 2.8 to 7.3). The TSV3 PCR for the laboratory was 23% (CPs range, 11% to 41%). The MDROM for the laboratory was 19% (CPs range, 9% to 31%), whereas the ROM was 36% (CPs range, 29% to 50%). Linear regression analysis of AUS:M ratio versus TSV3 PCR and MDROM demonstrated a moderate positive correlation but a weak negative correlation to the ROM. Deviations from established targets were attributed to multiple factors.

Conclusion

The findings of this study underscore the importance of using a combination of metrics to evaluate diagnostic practices. By dissecting the practice patterns of each CP, the authors can measure different aspects of their performance and provide individualized feedback.
Identifying the predictive role and the related drugs of oxidative stress genes in the hepatocellular carcinoma
Authors: Nie Guole , Zhu Xingwang , Zhang Honglong , Wang Haiping , Yan Jun , Li Xun
Published: April 2024

Background and Aims

Oncogenesis and tumor development have been related to oxidative stress (OS). The potential diagnostic utility of OS genes in hepatocellular carcinoma (HCC), however, remains uncertain. As a result, this work aimed to create a novel OS related‐genes signature that could be used to predict the survival of HCC patients and to screen OS related‐genes drugs that might be used for HCC treatment.

Methods

We used The Cancer Genome Atlas (TCGA) database and the Gene Expression Omnibus (GEO) database to acquire mRNA expression profiles and clinical data for this research and the GeneCards database to obtain OS related‐genes. Following that, biological functions from Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) were performed on differentially expressed OS‐related genes (DEOSGs). Subsequently, the prognostic risk signature was constructed based on DEOSGs from the TCGA data that were screened by using univariate cox analysis, and the Least Absolute Shrinkage and Selection Operator (LASSO) regression, and multivariate cox analysis. At the same time, we developed a prognostic nomogram of HCC patients based on risk signature and clinical‐pathological characteristics. The GEO data was used for validation. We used the receiver operating characteristic (ROC) curve, calibration curves, and Kaplan–Meier (KM) survival curves to examine the prediction value of the risk signature and nomogram. Finally, we screened the differentially expressed OS genes related drugs.

Results

We were able to recognize 9 OS genes linked to HCC prognosis. In addition, the KM curve revealed a statistically significant difference in overall survival (OS) between the high‐risk and low‐risk groups. The area under the curve (AUC) shows the independent prognostic value of the risk signature model. Meanwhile, the ROC curves and calibration curves show the strong prognostic power of the nomogram. The top three drugs with negative ratings were ZM‐336372, lestaurtinib, and flunisolide, all of which inversely regulate different OS gene expressions.

Conclusion

Our findings indicate that OS related‐genes have a favorable prognostic value for HCC, which sheds new light on the relationship between oxidative stress and HCC, and suggests potential therapeutic strategies for HCC patients.
Transient Study of Photoluminescence in Nanowaveguides Doped with Quantum Emitters and Metallic Nanoparticles
Authors: Brassem Grant , Singh Mahi R , Yastrebov Sergey
Published: April 2024

We have studied the time‐dependent optical properties of nanowaveguides containing an ensemble of noninteracting quantum emitters and interaction metallic nanoparticles. We have developed a theory for transient photoluminescence (PL) and exciton population density using the density matrix method. In our theory, we have included the effect of the dipole‐dipole interaction (DDI) between metallic nanoparticles along with the effect of the surface plasmon polaritons (SPPs) created by metallic nanoparticles. We compared our theory with the transient PL experiments of nanohybrids fabricated from CdSe/ZnS quantum dots and an Ag nanorod array. A good agreement between theory and PL experiment is found. We have also examined the transient behavior of the photoluminescence in the presence of the DDI and SPP couplings. It is observed that the number of transient PL oscillations increases as the DDI coupling increases. The width of the transient peaks also increases as the amount of the DDI coupling increases. Finally, we predicted that the peaks of the transient PL oscillation split from one peak to two peaks as the intensity of the DDI coupling reaches the strong coupling limit. The strong coupling limit is defined when the DDI coupling is larger than the PL decay rates. This finding can be used to fabricate nano switches by using one peak as the OFF position and two peaks as the ON position. The above findings also suggest the transient plasmonic properties of nanowaveguides can be controlled by the SPP and DDI couplings. These findings have potential applications in the development of transient nanoscale plasmonic devices such as nano detectors and optical nano switches.
Conformational Analysis of Conjugated Organic Materials: What Are My Heteroatoms Really Doing?
Authors: Thorley Karl J. , Nielsen Christian B.
Published: April 2024

Organic semiconductor small molecules and polymers often incorporate heteroatoms into their chemical structures to affect the electronic properties of the material. A particular design philosophy has been to use these heteroatoms to influence torsional potentials, since the overlap of adjacent π‐orbitals is most efficient in planar systems and is critical for charge delocalization in these systems. Since these design rules became popular, the messages from the earlier works have become lost in a sea of reports of “conformational locks”, where the non‐covalent interactions have relatively small contributions to planarizing torsional potentials. Greater influences can be found in the stabilization by extended conjugation, consideration of steric repulsion, and the interactions involving solubilizing chains and neighboring molecules or polymer chains in condensed phases.
An ultrahigh input impedance low noise analog front‐end design for epilepsy brain recording system
Authors: Anh Nguyen Thi Ngoc , Tien Nguyen The , Tuan Nguyen Van , Tuan Dao Duy , Thanh Vu Van , Thai Pham Quang , Au Huynh Hai , Tho Nguyen Van
Published: April 2024

This paper presents an ultrahigh input impedance, low noise, and wide bandwidth four‐channels analog front‐end (AFE) for low‐power neural recording systems. To achieve high input impedance, the buffer channels are placed between the electrodes and the main amplifier stage of the AFE. The buffer is designed with low noise and low power consumption to obtain high input impedance of overall AFE while maintaining low input‐referred noise and low power consumption. A chopper capacitively coupled chopper instrumentation amplifier (CCIA) is placed after the buffer as the main amplifier stage of the AFE to improve the common mode rejection ratio (CMRR) and the input‐referred noise of the overall AFE design. A new chopper stabilization control technique is proposed and used in the CCIA stage to reduce the charge injection and clock feedthrough and consequently the high‐frequency ripple of the AFE output signal. A programmable gain amplifier (PGA) is designed as the third stage to adjust the overall gain of the AFE. Benefiting from PGA, the AFE can adapt its gain with both action potential and local field potential signals. To reduce the number of the electrode to be implanted and reduce the impedance mismatch that causes the degradation on overall CMRR performance, two AFE channels shared a reference electrode followed by a reference buffer. The proposed AFE is designed and simulated using a standard 180 nm CMOS process and operates in a wide frequency band of 2.1 to 2500 Hz with low input‐referred noise of 1.6 μVrms and a CMRR over 80 dB at 2.1 Hz. The total power consumption is lower than 4.3 μW per channel. With the proposed structure of AFE, the input impedance is 35 GΩ @ 21 Hz and the minimum impedance over operational bandwidth is 75 MΩ @ 2.5 kHz.
Physiological, body composition, and body mass measures show that a developmental measure of weight suppression is more valid than the traditional measure
Authors: Lowe Michael R. , Singh Simar , Rosenbaum Michael , Mayer Laurel
Published: April 2024

Objective

The traditional measure of weight suppression (TWS; the difference between an individual's highest past weight at adult height and current weight), has been associated with many psychological, behavioral and biological variables in those with eating disorders. A new measure of weight suppression, called developmental weight suppression (DWS), corrects two major problems in the original measure. Initial research indicates that DWS represents a superior operationalization of the construct weight suppression was originally designed to measure (Lowe [1993, Psychol Bull, 114: 100]). This study is the first to examine the relation between both WS measures and weight history, body composition and a variety of metabolic hormones.

Methods

Data were collected in 91 women with bulimia nervosa (BN) or BN‐spectrum disorders.

Results

Both weight suppression indices were related to multiple hormones. However, multiple regression analyses showed that the independent effects of DWS differed from the independent effects of TWS in that only DWS was negatively related to: (1) current z‐BMI, (2) body fat percentage, and (3) insulin, leptin, T3 free, and TSH. This differential pattern also occurred when results were corrected for multiple comparisons.

Discussion

Findings provide stronger biological support for the construct validity of DWS than TWS and suggest that: (1) from the perspective of individuals with BN, high DWS embodies success at food restriction and weight loss, (2) elevated DWS may trap individuals with BN in a powerful biobehavioral bind, and (3) DWS is the preferred measure of weight suppression in future research on eating disorders.

Public Significance

Most individuals with bulimia nervosa lose substantial weight in the process of developing their disorder. Such weight suppression is related to many characteristics of those with the eating disorder bulimia nervosa. This study shows why a new measure of weight suppression, based on an individual's growth during development, is more biologically valid than the traditional measure of weight suppression.
Boldness suppresses hoarding behavior in food hoarding season and reduces over‐wintering survival in a social rodent
Authors: Gan Lin , Tian Shuang‐Jie , Wang De‐Hua , Liu Wei
Published: April 2024

The “pace‐of‐life” syndrome (POLS) framework can encompass multiple personality axes that drive important functional behaviors (e.g., foraging behavior) and that co‐vary with multiple life history traits. Food hoarding is an adaptive behavior important for an animal's ability to adapt to seasonal fluctuations in food availability. However, the empirical evidence for the relationships between animal personality and hoarding behavior remains unclear, including its fitness consequences in the POLS framework. In this study, the Mongolian gerbil (Meriones unguiculatus), a social rodent, was used as a model system to investigate how boldness or shyness is associated with food hoarding strategies during the food hoarding season and their impact on over‐winter survival and reproduction at both individual and group levels. The results of this study showed that, compared with shy gerbils, bold gerbils had a lower effort foraging strategy during the food hoarding season and exhibited lower over‐winter survival rates. However, bold–shy personality differences had no effect on over‐winter reproduction. These findings suggest that the personality is a crucial factor influencing the foraging strategy during the food hoarding season in Mongolian gerbils. Personality may be related to energy states or the reaction to environmental changes (e.g., predation risk and food availability) in bold or shy social animals. These results reflect animal life history trade‐offs between current versus future reproduction and reproduction versus self‐maintenance, thereby helping Mongolian gerbils in adapting to seasonal fluctuations in their habitat.
Prevalence and Predictors of Gestational Diabetes Mellitus in Sub‐Saharan Africa: A 10‐Year Systematic Review
Authors: Abera Daniel Ataanya , Larbie Christopher , Abugri James , Ofosu Mina , Mutocheluh Mohamed , Dongsogo Julius
Published: April 2024

Background

Gestational diabetes mellitus (GDM) remains a global public health problem, which affects the well‐being of mothers and their children in sub‐Saharan Africa (SSA). Studies conducted in different geographical areas provide varied results on its prevalence and predictors. Understanding the extent and predictors of GDM in SSA is important for developing effective interventions and policies. Thus, this review aimed to investigate the prevalence of GDM and its predictive factors in sub‐Saharan Africa.

Methods

We followed the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA) standards in this review. An extensive search of the PubMed, Web of Sciences and EMBASE databases was carried out covering papers from 2012 to 2022 to assess the prevalence and predictors of GDM. Microsoft Excel 2019 was utilised for study management. GraphPad Prism Version 8.0 and the MedCalc statistical software were employed for data analysis. The findings were analysed using textual descriptions, tables, forest plots and heat maps.

Results

Using 30 studies with 23,760 participants that satisfied the inclusion criteria, the review found the overall prevalence of GDM in SSA to be 3.05% (1.85%–4.54%). History of preterm delivery, alcohol consumption, family history of diabetes, history of stillbirths, history of macrosomia, overweight or obesity and advanced mother age were all significant predictors of gestational diabetes. Additionally, various biomarkers such as haemoglobin, adiponectin, leptin, resistin, visfatin, vitamin D, triglycerides and dietary intake type were identified as significant predictors of GDM.

Conclusion

In sub‐Saharan Africa, there is a high pooled prevalence of gestational diabetes mellitus. In the light of the predictors of GDM identified in this review, it is strongly recommended to implement early screening for women at risk of developing gestational diabetes during their pregnancy. This proactive approach is essential for enhancing the overall well‐being of both mothers and children.
Evaluation of free radical‐induced structural changes and their effect on antioxidant and anti‐inflammatory activities of UV/H2O2‐degraded dextrans
Authors: Zhu Biyang , Li Liuting , Hileuskaya Kseniya , Xu Baojun , You Lijun
Published: April 2024

Although ultraviolet (UV)/H2O2 treatment could effectively improve the bioactivities of polysaccharides, the relationship between free radical‐induced structural changes and the bioactivities of products remains unknown. Therefore, this work investigated the changes in the chemical characteristics and chain conformations of degraded dextrans by the UV/H2O2 system as well as their antioxidant and anti‐inflammatory activities. The apparent degradation efficiencies of dextrans under different UV/H2O2 parameters were first investigated. UV/H2O2 treatment effectively destroyed the pyranose rings and glycosidic bonds of dextrans and significantly improved their uronic acid and carboxy contents. Furthermore, conformational studies revealed that besides the rapid decrease in the molecular weight, the compact spherical conformation of dextrans was gradually depolymerized into the flexible random coil conformation. Moreover, the significant antioxidant and anti‐inflammatory activities of the degraded dextrans were mainly attributed to their more extended random coil chains, increased quantity of reducing groups, and lower molecular sizes. This study contributes to investigating the structure–activity relationship of polysaccharides prepared by free radicals‐mediated degradation.
Atroposelective Construction of Naphthylpyrazoles by Chiral Phosphoric Acid Catalyzed Enantioselective Cross‐Coupling of Pyrazoles with Naphthoquinone Esters
Authors: Luo Xi , Li Sen , Tian Yuting , Tian Yuqi , Gao Limei , Wang Qiang , Zheng Yongsheng
Published: April 2024

The catalytic asymmetric reaction of 5‐aminopyrazoles with naphthoquinone esters has been established. A wide range of unprecedented axially chiral naphthylpyrazole derivatives (29 examples) have been synthesized in moderate to excellent yields (up to 99 % yield) with excellent enantioselectivities (up to 99 % ee) by utilizing chiral phosphoric acid as a catalyst. This protocol features mild reaction conditions, a broad substrate scope, good scalability and facile derivatization. Moreover, preliminary mechanistic investigation was conducted to elucidate the mechanism.