bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and leishmanicidal evaluation of sulfanyl‐ and sulfonyl‐tethered functionalized benzoate derivatives featuring a nitroimidazole moiety
Authors: Rodríguez Miguel , Gutiérrez Joyce , Domínguez José , Peixoto Philippe A. , Fernández Alexis , Rodríguez Noris , Deffieux Denis , Rojas Luis , Quideau Stéphane , Pouységu Laurent , Charris Jaime 
Published: March 2020

AbstractA series of new nitroimidazole‐containing derivatives was synthesized by coupling of 2‐[2‐(2‐methyl‐5‐nitro‐1H‐imidazol‐1‐yl)ethylthio]ethanol with diversely substituted benzoic acids. Upon treatment with m‐CPBA, 12 of these sulfanyl compounds were further oxidized to their sulfonyl analogs. All the 26 synthetic compounds were examined for in vitro activity against Leishmania (V.) braziliensis and Leishmania (L.) mexicana, and some of them displayed an efficient antileishmanial activity. Among the compounds tested, the catecholic derivative 2‐{[2‐(2‐methyl‐5‐nitro‐1H‐imidazol‐1‐yl)ethyl]sulfanyl}ethyl 3,4‐dihydroxybenzoate (9a, LC50 = 13 and 11 µM) and the pyrogallolic derivative 2‐{[2‐(2‐methyl‐5‐nitro‐1H‐imidazol‐1‐yl)ethyl]sulfanyl}ethyl 3,4,5‐trihydroxybenzoate (9b, LC50 = 4 and 1 µM) were the most active ones against the two Leishmania strains.
Simultaneous detection of fungal (1,3)‐β‐d‐glucan and procalcitonin using a dual‐label time‐resolved fluorescence immunoassay
Authors: Li Huitao , Huang Zhifeng , Lin Binchun , Chen Xueyu , Xiong Xiaoyun , Cao Aifen , Yang Chuanzhong 
Published: March 2020

AbstractNeonatal infectious diseases are a serious threat to the health of newborns. The aim was to establish a new detection method for the simultaneous measurement of (1,3)‐β‐d‐glucan and procalcitonin in serum for the early screening and efficacy testing of neonatal infectious diseases. We established a sandwich dual‐label time‐resolved fluorescence immunoassay (TRFIA): anti‐(1,3)‐β‐d‐glucan/procalcitonin antibodies immobilized on 96‐well plates captured (1,3)‐β‐d‐glucan/procalcitonin antigens and then banded together with the detection antibodies labeled with europium(III) (Eu3+)/samarium(III) (Sm3+) chelates. Finally, time‐resolved fluorometry was used to measure the fluorescence intensity. The linear correlation coefficient (R2) of the (1,3)‐β‐d‐glucan standard curve was 0.9913, and the R2 of the procalcitonin standard curve was 0.9911. The detection sensitivity for (1,3)‐β‐d‐glucan was 0.4 pg/mL (dynamic range: 0.6–90 pg/mL), and the average recovery was 101.55%. The detection sensitivity for procalcitonin was 0.02 ng/mL (dynamic range: 0.05–95 ng/mL), and the average recovery was 104.61%. There was a high R2 between the present TRFIA method and a commercially available assay (R2 = 0.9829 for (1,3)‐β‐d‐glucan and R2 = 0.9704 for procalcitonin). Additionally, the cutoff values for (1,3)‐β‐d‐glucan and procalcitonin were 23.95 pg/mL and 0.055 ng/mL, respectively. The present TRFIA method has high sensitivity, accuracy, and specificity and is an effective method for early screening and efficient testing of neonatal invasive fungal infection.
Biotransformation of 5‐Hydroxymethylfurfural to 2,5‐Furandicarboxylic Acid by a Syntrophic Consortium of Engineered Synechococcus elongatus and Pseudomonas putida
Authors: Lin Tzu‐Yu , Wen Rex C. , Shen Claire R. , Tsai Shen‐Long 
Published: March 2020

Abstract2,5‐furandicarboxylic acid (FDCA) is one of the top platform chemicals that can be produced from biomass feedstock. To make the cost of industrial FDCA production compatible with plastics made from fossils, the price of substrates and process complexity should be reduced. The aim of this research is to create a CO2‐driven syntrophic consortium for the catalytic conversion of renewable biomass‐derived 5‐hydroxymethylfurfural (HMF) to FDCA. Sucrose produced from carbon fixation by the engineered Synechococcus elongatus serves as the sole carbon source for the engineered Pseudomonas putida to catalyze the reaction of HMF to FDCA. The yield of FDCA by the consortium reaches around 70% while the conversion of HMF is close to 100%. With further surface engineering to clump the two strains, the FDCA yield is elevated to almost 100% via the specific association between an Src homology 3 (SH3) domain and its ligand. The syntrophic consortium successfully demonstrates its green and cost‐effective characteristics for the conversion of CO2 and biomass into platform chemicals.
Effect of structured use of preoperative portal vein embolization on outcomes after liver resection of perihilar cholangiocarcinoma
Authors: Franken L C , Rassam F , van Lienden K P , Bennink R J , Besselink M G , Busch O R , Erdmann J I , Gulik T M , Olthof P B 
Published: March 2020

Abstract

Background
Portal vein embolization (PVE) is performed to reduce the risk of liver failure and subsequent mortality after major liver resection. Although a cut-off value of 2·7 per cent per min per m2 has been used with hepatobiliary scintigraphy (HBS) for future remnant liver function (FRLF), patients with perihilar cholangiocarcinoma (PHC) potentially benefit from an additional cut-off of 8·5 per cent/min (not corrected for body surface area). Since January 2016 a more liberal approach to PVE has been adopted, including this additional cut-off for HBS of 8·5 per cent/min. The aim of this study was to assess the effect of this approach on liver failure and mortality.

Methods
This was a single-centre retrospective study in which consecutive patients undergoing liver resection under suspicion of PHC in 2000–2015 were compared with patients treated in 2016–2019, after implementation of the more liberal approach. Primary outcomes were postoperative liver failure (International Study Group of Liver Surgery grade B/C) and 90-day mortality.

Results
Some 191 patients with PHC underwent liver resection. PVE was performed in 6·4 per cent (9 of 141) of the patients treated in 2000–2015 and in 32 per cent (16 of 50) of those treated in 2016–2019. The 90-day mortality rate decreased from 16·3 per cent (23 of 141) to 2 per cent (1 of 50) (P = 0·009), together with a decrease in the rate of liver failure from 19·9 per cent (28 of 141) to 4 per cent (2 of 50) (P = 0·008). In 2016–2019, 24 patients had a FRLF greater than 8·5 per cent/min and no liver failure or death occurred, suggesting that 8·5 per cent/min is a reliable cut-off for patients with suspected PHC.

Conclusion
The major decrease in liver failure and mortality rates in recent years and the simultaneous increased use of PVE suggests an important role for PVE in reducing adverse outcomes after surgery for PHC.
Development and validation of novel nomograms for predicting the survival of patients after surgical resection of pancreatic ductal adenocarcinoma
Authors: Li Ge , Chen Jiang‐Zhi , Chen Shi , Lin Sheng‐Zhe , Pan Wei , Meng Ze‐Wu , Cai Xin‐Ran , Chen Yan‐Ling 
Published: March 2020

AbstractBackground/AimsPancreatic ductal adenocarcinoma (PDAC) is associated with high mortality, even after surgical resection. The existing predictive models for survival have limitations. This study aimed to develop better nomograms for predicting overall survival (OS) and cancer‐specific survival (CSS) in PDAC patients after surgery.MethodsA total of 6323 PDAC patients were retrospectively recruited from the Surveillance, Epidemiology, and End Results (SEER) database and randomly allocated into training, validation, and test cohorts. Multivariate Cox regression analysis was conducted to identify significant independent factors for OS and CSS, which were used for construction of nomograms. The performance was evaluated, validated, and compared with that of the 8th edition AJCC staging system.ResultsTen independent factors were significantly correlated with OS and CSS. The 1‐, 3‐, and 5‐year OS rates were 40%, 20%, and 15%, and 1‐, 3‐, and 5‐year CSS rates were 45%, 24%, and 19%, respectively. The nomograms were calibrated well, with c‐indexes of 0.640 for OS and 0.643 for CSS, respectively. Notably, relative to the 8th edition AJCC staging system, the nomograms were able to stratify each AJCC stage into three prognostic subgroups for more robust risk stratification. Furthermore, the nomograms achieved significant clinical validity, exhibiting wide threshold probabilities and high net benefit. Performance assessment also showed high predictive accuracy and reliability.ConclusionsThe predictive ability and reliability of the established nomograms have been validated, and therefore, these nomograms hold potential as novel approaches to predicting survival and assessing survival risks for PDAC patients after surgery.
From 360° camera toward to virtual map app: Designing low‐cost pilot study
Authors: Netek Rostislav , Burian Tomas , Macecek Martin 
Published: March 2020

AbstractCurrently, virtual reality (VR) is a trend both in general and in specific fields such as interactive maps. The article aims to test the possibilities of deployment of low‐cost virtual reality environment for the 3D spatial panoramic application. It discusses and compares modern trends in hardware (panoramic cameras and glasses) and software in the field of virtual reality. Many panoramic map applications (e.g., the well‐known “Google Street View”) allow us to navigate through applications using VR headsets or on an ordinary 2D monitor. The main aim of the article is to design, develop, and deploy VR map application with different levels of user interaction. It presents two pilot studies with different user's interactivity and technical solutions: “simple” 2D‐based map with 360° panoramic photos and “true” 3D application for VR glasses. The article focuses on the possibilities of creating low‐cost map applications. Therefore, the working process “from camera toward to virtual map application” is described as followed‐up case studies.
Therapeutic Targeting of Cancer Metabolism with Triosephosphate Isomerase
Authors: Pekel Gonca , Ari Ferda 
Published: March 2020

AbstractThe increase in glycolytic flux in cancer, known as aerobic glycolysis, is one of the most important hallmarks of cancer. Therefore, glycolytic enzymes have importance in understanding the molecular mechanism of cancer progression. Triosephosphate isomerase (TPI) is one of the key glycolytic enzymes. Furthermore, it takes a part in gluconeogenesis, pentose phosphate pathway and fatty acid biosynthesis. To date, it has been shown altered levels of TPI in various cancer types, especially in metastatic phenotype. According to other studies, TPI might be considered as a potential therapeutic target and a cancer‐related biomarker in different types of cancer. However, its function in tumor formation and development has not been fully understood. Here, we reviewed the relationship between TPI and cancer for the first time
Halogenation‐Guided Chemical Screening Provides Insight into Tjipanazole Biosynthesis by the Cyanobacterium Fischerella ambigua
Authors: Chilczuk Tomasz , Schäberle Till F. , Vahdati Sahel , Mettal Ute , El Omari Mustafa , Enke Heike , Wiese Michael , König Gabriele M. , Niedermeyer Timo H. J. 
Published: March 2020

AbstractHalogenated natural products (HNPs) show a wide range of interesting biological activities. Chemistry‐guided screening with a software tool dedicated to identifying halogenated compounds in HPLC‐MS data indicated the presence of several uncharacterised HNPs in an extract of the cyanobacterium Fischerella ambigua (Näg.) Gomont 108b. Three new natural products, tjipanazoles K, L, and M, were isolated from this strain together with the known tjipanazoles D and I. Taking into account the structures of all tjipanazole derivatives detected in this strain, reanalysis of the tjipanazole biosynthetic gene cluster allowed us to propose a biosynthetic pathway for the tjipanazoles. As the isolated tjipanazoles show structural similarity to arcyriaflavin A, an inhibitor of the clinically relevant multidrug‐transporter ABCG2 overexpressed by different cancer cell lines, the isolated compounds were tested for ABCG2 inhibitory activity. Only tjipanazole K showed appreciable transporter inhibition, whereas the compounds lacking the pyrrolo[3,4‐c] ring or featuring additional chloro substituents were found to be much less active.
A Selective Fluorogenic Peptide Substrate for the Human Mitochondrial ATP‐Dependent Protease Complex ClpXP
Authors: Sha Zhou , Fishovitz Jennifer , Wang Susan , Chilakala Sujatha , Xu Yan , Lee Irene 
Published: March 2020

AbstractThe goal of this work is to identify differences in the substrate determinants of two human mitochondrial matrix ATP‐dependent proteases, human ClpXP (hClpXP) and human Lon (hLon). This information allows the generation of protease‐specific peptide substrates that can be used as chemical biology tools to investigate the physiological functions of hClpXP. These enzymes play a role in protein quality control, but currently the physiological functions of human ClpXP are not well defined. In this study, the degradation profile of casein, an alanine positional scanning decapeptide library, and a specific peptide sequence found in an endogenous substrate of bacterial ClpXP by hClpXP as well as hLon were examined. Based on our findings, we generated a specific fluorogenic peptide substrate, FR‐Cleptide, for hClpXP with a kcat of 2.44±0.15 s−1 and Km=262±43 μM, respectively. The FR‐Cleptide substrate was successfully used to identify a leucine methyl ketone as a potent lead inhibitor, and to detect endogenous hClpXP activity in HeLa cell lysate. We propose that the fluorogenic peptide substrate is a valuable tool for quantitatively monitoring the activity of hClpXP in cell lysate, as well as mechanistic characterization of hClpXP. The peptide‐based chemical tools developed in this study will complement the substrates developed for human Lon in aiding the investigation of the physiological functions of the respective protease.
Evaluating Terminator Strength Based on Differentiating Effects on Transcription and Translation
Authors: He Zhiyun , Duan Yanting , Zhai Weiji , Zhang Xiaomei , Shi Jinsong , Zhang Xiaojuan , Xu Zhenghong 
Published: March 2020

AbstractTranscription terminators play a role in terminating the progress of gene transcription, and are thus essential elements in the gene circuit. Terminators have two main functions: terminating gene transcription and improving the stability of gene transcripts during translation. We therefore considered the detailed characteristics of terminators in relation to their different roles in gene transcription and translation, including transcription shut‐down degree (α) and upstream mRNA protection capacity (β), and apparent termination efficiency (η) reflecting the overall regulatory effect of the terminator. Based on a dual‐reporter gene system, we constructed three terminator‐probe plasmids to investigate each characteristic in Escherichia coli. According to multiple regression analysis, the transcription shut‐down degree and the upstream mRNA protection capacity contributed almost equally to the apparent termination efficiency. Sequence analysis of 12 terminators demonstrated that the terminator sequence was dominated by GC bases, and that a high ratio of GC bases in the stem structure of terminators might be associated with a high degree of transcription shut‐down. This comprehensive characterization of terminators furthers our understanding of the role of terminators in gene expression and provides a guide for synthetic terminator design.
Transfemoral transcatheter puncture of interventricular septum in a swine model: A novel transfemoral‐venous access to left ventricle with the assistance of arterio‐venous circuit
Authors: Yan Chaowu , Wan Linyuan , Li Li , Li Hua , Du Baopeng , Hao Shijie 
Published: March 2020

AbstractObjectiveVia subclavian/jugular vein, successful puncture of interventricular septum (IVS) has been achieved transvenously. However, the approach was limited by acute entry‐angle. The study was conducted to investigate a novel transcatheter puncture of IVS via femoral access and transfemoral‐venous access to left ventricle (LV) through IVS.MethodsVia femoral artery, transcatheter puncture of mid‐IVS was performed with a custom‐made nickel–titanium needle and 6F‐sheath in 16 healthy mini‐swine. Then femoral arterio‐venous circuit was established through IVS. After pre‐dilation of IVS, a 20F‐sheath was introduced into LV transvenously over‐the‐guidewire in 15 swine. Furthermore, transfemoral‐venous TAVR was attempted with the approach in another swine. IVS was evaluated postoperatively and was further confirmed pathologically 2 months later.ResultsAll transcatheter puncture of IVS was performed successfully in LV and the mid‐IVS thickness was 7.67 ± 0.98 mm. In all swine, femoral arterio‐venous circuit was established via IVS, and a 20F‐sheath was introduced into LV and aorta transfemoral‐venously (entry‐angle: 145.3 ± 12.2° in front view). After the procedure, there was one swine with moderate tricuspid‐regurgitation and five swine with mild residual‐shunt (2.6 ± 0.7 mm). Two months later, residual‐shunt was still detected in three swine and the communication was confirmed pathologically. In other swine, no defect occurred and replacement‐scar was identified along puncture‐tract. In the swine underwent transfemoral‐venous TAVR, prosthetic valve was deployed successfully with good function.ConclusionsTransfemoral transcatheter puncture of IVS is feasible and safe in a swine model, and large sheath can be introduced into LV transfemoral‐venously using the novel access with the aid of vessel circuit.
Transition Metal‐Catalyzed and Metal‐Free Cyclization Reactions of Alkynes with Nitrogen‐Containing Substrates: Synthesis of Pyrrole Derivatives
Authors: Neto Jose S. S. , Zeni Gilson 
Published: March 2020

AbstractThis review describes the efforts in the synthesis of pyrrole derivatives using the reaction of alkynes with nitrogen‐compounds under transition metal‐catalyzed and metal‐free conditions, in the past decade. We initially focused on the methods of preparation of pyrrole derivatives using reactions catalyzed by transition metal. In this part, we described the syntheses of 1‐pyrrolines, 2‐pyrrolines, 3‐pyrrolines, pyrroles, and pyrrolidines following an alphabetical order of the transition metal used for the synthesis. Subsequently, we presented the synthesis of these pyrrole derivatives under metal‐free conditions.
Recent Advances in Synthesis and Utilization of Ultra‐low Loading of Precious Metal‐based Catalysts for Fuel Cells
Authors: Lori Oran , Elbaz Lior 
Published: March 2020

AbstractCost of polymer electrolyte membrane fuel cells (PEMFC) is one of the most acute setbacks delaying this technology's worldwide deployment and commercialization. Platinum, the most common and effective catalyst for the oxygen reduction reaction (ORR), is a scarce element which accounts for more than 45 % of PEMFC stack cost. One of the preferred proposed paths to substantially reduce stack costs is by dramatically lowering precious metal loading in a membrane electrode assembly (MEA) to account for up to 11.3 gPt per midsize vehicle (US‐DOE 2020 target). This Minireview surveys the latest synthetical and methodical advances in making and utilizing ultra‐low loading precious metal ORR catalyst in PEM fuel cells.
Structural Designs and in‐situ X‐ray Characterizations of Metal Phosphides for Electrocatalysis
Authors: Zhang Youkui , Song Li 
Published: March 2020

AbstractElectrocatalysis is one of the most attractive technologies for renewable energy storage and conversion to meet global energy demand. Thus it has attracted considerable research efforts for the development of inexpensive and efficient electrocatalysts. Recent research progress has demonstrated that the Earth‐abundant metal‐based phosphides are attractive materials for efficient electrocatalysis because of attractive features such as tunable structure and high activity. In this Minireview, we summarize the latest research progress of metal phosphide‐based materials as efficient electrocatalysts. The synthesis approaches of metal phosphides and the factors that influence structural reconstruction in certain reactions are reviewed and discussed. Specifically, advanced in‐situ X‐ray characterization techniques for metal phosphide research in the field of electrocatalysis are also highlighted. Finally, the current challenges and future perspectives for these materials are presented.
Synthesis of Dinuclear Mo−Fe Hydride Complexes and Catalytic Silylation of N2
Authors: Ishihara Kodai , Araki Yuna , Tada Mizuki , Takayama Tsutomu , Sakai Yoichi , Sameera W. M. C. , Ohki Yasuhiro 
Published: March 2020

AbstractTwo transition‐metal atoms bridged by hydrides may represent a useful structural motif for N2 activation by molecular complexes and the enzyme active site. In this study, dinuclear MoIV‐FeII complexes with bridging hydrides, CpRMo(PMe3)(H)(μ‐H)3FeCp* (2 a; CpR=Cp*=C5Me5, 2 b; CpR=C5Me4H), were synthesized via deprotonation of CpRMo(PMe3)H5 (1 a; CpR=Cp*, 1 b; CpR=C5Me4H) by Cp*FeN(SiMe3)2, and they were characterized by spectroscopy and crystallography. These Mo−Fe complexes reveal the shortest Mo−Fe distances ever reported (2.4005(3) Å for 2 a and 2.3952(3) Å for 2 b), and the Mo−Fe interactions were analyzed by computational studies. Removal of the terminal Mo−H hydride in 2 a–2 b by [Ph3C]+ in THF led to the formation of cationic THF adducts [CpRMo(PMe3)(THF)(μ‐H)3FeCp*]+ (3 a; CpR=Cp*, 3 b; CpR=C5Me4H). Further reaction of 3 a with LiPPh2 gave rise to a phosphido‐bridged complex Cp*Mo(PMe3)(μ‐H)(μ‐PPh2)FeCp* (4). A series of Mo−Fe complexes were subjected to catalytic silylation of N2 in the presence of Na and Me3SiCl, furnishing up to 129±20 equiv of N(SiMe3)3 per molecule of 2 b. Mechanism of the catalytic cycle was analyzed by DFT calculations.
From Specific γ‐CD/[Nb6Cl12(H2O)6]2+ Recognition to Biological Activity Tuning
Authors: Ivanov Anton A. , Pozmogova Tatiana N. , Solovieva Anastasiya O. , Frolova Tatiana S. , Sinitsyna Olga I. , Lundovskaya Olga V. , Tsygankova Alphiya R. , Haouas Mohamed , Landy David , Benassi Enrico , Shestopalova Lidiya V. , Falaise Clément , Cadot Emmanuel , Shestopalov Michael A. , Abramov Pavel A. , Sokolov Maxim N. 
Published: March 2020

AbstractSpecific molecular recognition of γ‐cyclodextrin (γ‐CD) by the cationic hexanuclear niobium [Nb6Cl12(H2O)6]2+ cluster complex in aqueous solutions results in a 1:1 supramolecular assembly {[Nb6Cl12(H2O)6]@γ‐CD}2+. NMR spectroscopy, isothermal titration calorimetry (ITC), and ESI‐MS were used to study the interaction between the inorganic cluster and the organic macrocycle. Such molecular association affects the biological activity of [Nb6Cl12(H2O)6]2+, decreasing its cytotoxicity despite enhanced cellular uptake. The 1:1 stoichiometry is maintained in solution over a large window of the reagents’ ratio, but crystallization by slow evaporation produces a 1:2 host–guest complex [Nb6Cl12(H2O)6@(γ‐CD)2]Cl2⋅20 H2O featuring the cluster encapsulated between two molecules of γ‐CD. The 1:2 complex was characterized by XRD, elemental analysis, IR spectroscopy, and thermogravimetric analysis (TGA). Quantum chemical calculations were performed to model host–guest interaction.