bluuebunny/crossref_metadata_2025 huggingface dataset:
Real-time loop-mediated isothermal amplification for rapid detection of Enterocytozoon hepatopenaei
Authors: Cai Shao-Xin , Kong Fan-De , Xu Shu-Fei , Yao Cui-Luan
Published: December 2018

Background

Enterocytozoon hepatopenaei (EHP) is a newly emerged microsporidian parasite that causes retarded shrimp growth in many countries. But there are no effective approaches to control this disease to date. The EHP could be an immune risk factor for increased dissemination of other diseases. Further, EHP infection involves the absence of obvious clinical signs and it is difficult to identify the pathogen through visual examination, increasing the risk of disease dissemination. It is urgent and necessary to develop a specific, rapid and sensitive EHP-infected shrimp diagnostic method to detect this parasite. In the present study, we developed and evaluated a rapid real-time loop-mediated isothermal amplification (real-time LAMP) for detection of EHP.

Methods

A rapid and efficient real-time LAMP method for the detection of EHP has been developed. Newly emerged EHP pathogens in China were collected and used as the sample, and three sets of specificity and sensitivity primers were designed. Three other aquatic pathogens were used as templates to test the specificity of the real-time LAMP assay. Also, we compared the real-time LAMP with the conventional LAMP by the serial dilutions of EHP DNA and their amplification curves. Application of real-time LAMP was carried out with clinical samples.

Results

Positive products were amplified only from EHP, but not from other tested species, EHP was detected from the clinical samples, suggesting a high specificity of this method. The final results of this assay were available within less than 45 min, and the initial amplification curve was observed at about 6 min. We found that the amplification with an exponential of sixfold dilutions of EHP DNA demonstrated a specific positive signal by the real-time LAMP, but not for the LAMP amplicons from the visual inspection. The real-time LAMP amplification curves demonstrated a higher slope than the conventional LAMP.

Discussion

In this study, pathogen virulence impacts have been increased in aquaculture and continuous observation was predominantly focused on EHP. The present study confirmed that the real-time LAMP assay is a promising and convenient method for the rapid identification of EHP in less time and cost. Its application greatly aids in the detection, surveillance, and prevention of EHP.
A retrospective study of surgical treatment and outcome among women with adnexal torsion in eastern Taiwan from 2010 to 2015
Authors: Huang Ci , Hong Mun-Kun , Chu Tang-Yuan , Ding Dah-Ching
Published: December 2018

Background

Adnexal torsion is a gynecologic emergency that requires surgical treatment. In this study, we reviewed the surgical outcomes of women with adnexal torsion in eastern Taiwan (Hualien county, area 4,629 km2, 330,000 residents).

Methods

This retrospective study included 42 women diagnosed with surgically-proven adnexal torsion from January 1, 2010, to September 31, 2015. We compared the symptoms, objective findings, and surgical outcomes of patients who underwent laparotomy or laparoscopy.

Results

The laparoscopy and laparotomy groups included 27 and 15 patients, respectively. The most common symptom and sign was abdominal pain, followed by nausea and vomiting. In all patients, an adnexal tumor was detected through ultrasound. The median and range of time from admission to surgery was 1.5 (1–11.5) and 1.0 (1–11) hours in the laparotomy and laparoscopy groups, respectively. Compared with those undergoing laparotomy, the smaller tumor size [7 (4.2–10) vs. 10 (7–17) cm] and shorter hospital stay [4 (2–8) vs. 6 (3–9) days] in patients undergoing laparoscopy were significantly noted, respectively (P < 0.01). No differences were observed in age, operative time, and blood loss between both groups. The surgeries performed were mostly detorsion with cystectomy and adnexectomy. The most common pathology was a simple ovarian cyst, followed by teratoma. Regarding the surgical types, older age is the only risk factor for radical surgery.

Discussion

Acute onset of abdominal pain with a presenting ovarian tumor is the most common feature of adnexal torsion. Laparoscopic surgical group showed a small tumor size and a short ER hospital stay than laparotomy. Older age is the risk factor for radical surgery.
Complete chloroplast genome sequences of Dioscorea: Characterization, genomic resources, and phylogenetic analyses
Authors: Zhao Zhenyu , Wang Xin , Yu Yi , Yuan Subo , Jiang Dan , Zhang Yujun , Zhang Teng , Zhong Wenhao , Yuan Qingjun , Huang Luqi
Published: December 2018

Dioscorea L., the largest genus of the family Dioscoreaceae with over 600 species, is not only an important food but also a medicinal plant. The identification and classification of Dioscorea L. is a rather difficult task. In this study, we sequenced five Dioscorea chloroplast genomes, and analyzed with four other chloroplast genomes of Dioscorea species from GenBank. The Dioscorea chloroplast genomes displayed the typical quadripartite structure of angiosperms, which consisted of a pair of inverted repeats separated by a large single-copy region, and a small single-copy region. The location and distribution of repeat sequences and microsatellites were determined, and the rapidly evolving chloroplast genome regions (trnK-trnQ, trnS-trnG, trnC-petN, trnE-trnT, petG-trnW-trnP, ndhF, trnL-rpl32, and ycf1) were detected. Phylogenetic relationships of Dioscorea inferred from chloroplast genomes obtained high support even in shortest internodes. Thus, chloroplast genome sequences provide potential molecular markers and genomic resources for phylogeny and species identification.
Identification of key candidate genes and biological pathways in bladder cancer
Authors: Gao Xin , Chen Yinyi , Chen Mei , Wang Shunlan , Wen Xiaohong , Zhang Shufang
Published: December 2018

Background

Bladder cancer is a malignant tumor in the urinary system with high mortality and recurrence rates. However, the causes and recurrence mechanism of bladder cancer are not fully understood. In this study, we used integrated bioinformatics to screen for key genes associated with the development of bladder cancer and reveal their potential molecular mechanisms.

Methods

The GSE7476, GSE13507, GSE37815 and GSE65635 expression profiles were downloaded from the Gene Expression Omnibus database, and these datasets contain 304 tissue samples, including 81 normal bladder tissue samples and 223 bladder cancer samples. The RobustRankAggreg (RRA) method was utilized to integrate and analyze the four datasets to obtain integrated differentially expressed genes (DEGs), and the gene ontology (GO) functional annotation and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis were performed. Protein-protein interaction (PPI) network and module analyses were performed using Cytoscape software. The OncoLnc online tool was utilized to analyze the relationship between the expression of hub genes and the prognosis of bladder cancer.

Results

In total, 343 DEGs, including 111 upregulated and 232 downregulated genes, were identified from the four datasets. GO analysis showed that the upregulated genes were mainly involved in mitotic nuclear division, the spindle and protein binding. The downregulated genes were mainly involved in cell adhesion, extracellular exosomes and calcium ion binding. The top five enriched pathways obtained in the KEGG pathway analysis were focal adhesion (FA), PI3K-Akt signaling pathway, proteoglycans in cancer, extracellular matrix (ECM)-receptor interaction and vascular smooth muscle contraction. The top 10 hub genes identified from the PPI network were vascular endothelial growth factor A (VEGFA), TOP2A, CCNB1, Cell division cycle 20 (CDC20), aurora kinase B, ACTA2, Aurora kinase A, UBE2C, CEP55 and CCNB2. Survival analysis revealed that the expression levels of ACTA2, CCNB1, CDC20 and VEGFA were related to the prognosis of patients with bladder cancer. In addition, a KEGG pathway analysis of the top 2 modules identified from the PPI network revealed that Module 1 mainly involved the cell cycle and oocyte meiosis, while the analysis in Module 2 mainly involved the complement and coagulation cascades, vascular smooth muscle contraction and FA.

Conclusions

This study identified key genes and pathways in bladder cancer, which will improve our understanding of the molecular mechanisms underlying the development and progression of bladder cancer. These key genes might be potential therapeutic targets and biomarkers for the treatment of bladder cancer.
Cost Management in Micro and Small Companies in the Mining Sector
Authors: Guidi Antonio Carlos , Morgan Levi , Montebelo Maria Imaculada , Corrêa Dalila Alves
Published: December 2018

According to Sebrae, micro and small companies represented 27% of the GDP in 2011 and 98.5% of all private companies in 2015. Despite this importance, in most cases they do not have employees with extensive cost management knowledge and the management practices of large companies are also repeated in them. Therefore, the aim of this paper is to analyze the operability of cost management at the micro and small companies that act in the mining and processing of dimension stones sector, searching for emphases on the presence of isomorphism. One hundred and sixty-two (162) companies were investigated in order to operationalize this study.  A structured questionnaire was used as a data collection procedure. Three different approaches were used in the statistical analysis of the collected data: descriptive statistics; the Mann-Whitney U test and Fisher’s exact test, and confirmatory and exploratory factor analysis. The results show the presence of mimetic isomorphism in the cost management practices of the companies researched. The research is limited to the sample, therefore, its findings can not be generalized. Based on this study, it was observed that future research should further develop the characterization of this economic phenomenon and study which resources would be required to improve management cost in micro and small companies in the analyzed segment. This is the first work that found the presence of mimetic isoformism among micro and small companies in the mining sector.
ABSORPTIVE CAPACITY AND THE INTERNATIONALIZATION PROCESS OF AN EMERGING MULTINATIONAL
Authors: Martignago Graciella , Cário Silvio Antônio Ferraz , Alperstedt Graziela Dias
Published: December 2018

Based on an evolutionary approach to international expansion and learning by a firm, the purpose of this study is to explain the absorptive capacity of knowledge for the internationalization process of emerging multinational companies. A qualitative study was conducted, which was inductive, descriptive and longitudinal, based on a case study of biggest cement company of South America. The study identified the previous knowledge, the new knowledge and described the acquisition process of knowledge, the transformation and the exploitation process involved in the internationalization. This study showed that even a mature company, leader in its home market, with experience in competition with the main international players, it needed to acquire new knowledge about  internationalization. The assimilation of knowledge was hampered by the prior knowledge structure and new routines were created before the external direct investment materialized. After the acquisition in the foreign market, the adaptation of routines created in the domestic market was developed.
The efficacy of free‐recall, cognitive load, and closed‐ended questions when children are asked to falsely testify about a crime
Authors: Wyman Joshua , Foster Ida , Crossman Angela , Colwell Kevin , Talwar Victoria
Published: December 2018

The current study evaluated the benefits of free‐recall, cognitive load, and closed‐ended questions on children's (ages 6 to 11; N = 147) true and false eyewitness disclosures. Children witnessed an experimenter find a stranger's wallet and were then asked to make a false denial, false accusation, true denial, or true accusation regarding an alleged theft. Overall, the free‐recall question resulted in longer, more forthcoming and more detailed disclosures from older children and those who made a truthful accusation; however, children under the age of 9 and lie‐tellers mostly relied on the closed‐ended questions to discuss the theft. Although the cognitive load questions resulted in newly recalled information, there were no significant narrative differences between true and false statements on these questions. These findings suggest that forensic professionals should consider a child's developmental level, statement veracity, and disclosure‐type (denial vs. accusation) when examining the efficacy of these commonly used questioning strategies.
Alcohol intoxicated witnesses' interpretation of social behavior in intimate partner violence
Authors: Karlén Malin Hildebrand , Lindqvist Bagge Ann‐Sophie , Fahlke Claudia , Armelius Kerstin
Published: December 2018

Alcohol intoxication affects social information processing, though research is scarce regarding how alcohol affected eyewitnesses' perception of social interaction within an applied forensic context. In the present study, the effects of alcohol intoxication on eyewitnesses' perception of interaction in intimate partner violence (IPV) were investigated. The participants (n = 152) were randomized to an experimental (alcohol) or control group (juice). After consumption, they viewed a filmed IPV scenario where both interacting parties were confrontational. Afterwards, they rated the involved parties' behavior. Several behaviors were perceived in a similar manner by intoxicated and sober participants, but intoxicated participants perceived both parties' attacking behaviors and some of the man's prosocial behaviors differently than sober participants. Hence, alcohol affected some, but not all, kinds of social behaviors investigated in the present study. This would be of interest to legal praxis and to future studies on intoxicated witnesses to interpersonal violence.
Biomedical Applications of Layer‐by‐Layer Self‐Assembly for Cell Encapsulation: Current Status and Future Perspectives
Authors: Liu Tengfei , Wang Ying , Zhong Wen , Li Bingyun , Mequanint Kibret , Luo Gaoxing , Xing Malcolm
Published: December 2018

Encapsulating living cells within multilayer functional shells is a crucial extension of cellular functions and a further development of cell surface engineering. In the last decade, cell encapsulation has been widely utilized in many cutting‐edge biomedical fields. Compared with other techniques for cell encapsulation, layer‐by‐layer (LbL) self‐assembly technology, due to the versatility and tunability to fabricate diverse multilayer shells with controllable compositions and structures, is considered as a promising approach for cell encapsulation. This review summarizes the state‐of‐the‐art and potential future biomedical applications of LbL cell encapsulation. First of all, a brief introduction to the LbL self‐assembly technique, including assembly mechanisms and technologies, is made. Next, different cell encapsulation strategies by LbL self‐assembly techniques are explained. Then, the biomedical applications of LbL cell encapsulation in cell‐based biosensors, cell transplantation, cell/molecule delivery, and tissue engineering, are highlighted. Finally, discussions on the current limitations and future perspectives of LbL cell encapsulation are also provided.
Simulating Inflammation in a Wound Microenvironment Using a Dermal Wound‐on‐a‐Chip Model
Authors: Biglari Sahar , Le Thi Y. L. , Tan Richard P. , Wise Steven G. , Zambon Alessandro , Codolo Gaia , De Bernard Marina , Warkiani Majid , Schindeler Aaron , Naficy Sina , Valtchev Peter , Khademhosseini Ali , Dehghani Fariba
Published: December 2018

Considerable progress has been made in the field of microfluidics to develop complex systems for modeling human skin and dermal wound healing processes. While microfluidic models have attempted to integrate multiple cell types and/or 3D culture systems, to date they have lacked some elements needed to fully represent dermal wound healing. This paper describes a cost‐effective, multicellular microfluidic system that mimics the paracrine component of early inflammation close to normal wound healing. Collagen and Matrigel are tested as materials for coating and adhesion of dermal fibroblasts and human umbilical vein endothelial cells (HUVECs). The wound‐on‐chip model consists of three interconnecting channels and is able to simulate wound inflammation by adding tumor necrosis factor alpha (TNF‐α) or by triculturing with macrophages. Both the approaches significantly increase IL‐1β, IL‐6, IL‐8 in the supernatant (p < 0.05), and increases in cytokine levels are attenuated by cotreatment with an anti‐inflammatory agent, Dexamethasone. Incorporation of M1 and M2 macrophages cocultured with fibroblasts and HUVECs leads to a stimulation of cytokine production as well as vascular structure formation, particularly with M2 macrophages. In summary, this wound‐on‐chip system can be used to model the paracrine component of the early inflammatory phase of wound healing and has the potential for the screening of anti‐inflammatory compounds.
Engineering Transport in Manganites by Tuning Local Nonstoichiometry in Grain Boundaries
Authors: Chiabrera Francesco , Garbayo Iñigo , López‐Conesa Lluis , Martín Gemma , Ruiz‐Caridad Alicia , Walls Michael , Ruiz‐González Luisa , Kordatos Apostolos , Núñez Marc , Morata Alex , Estradé Sonia , Chroneos Alexander , Peiró Francesca , Tarancón Albert
Published: December 2018

Interface‐dominated materials such as nanocrystalline thin films have emerged as an enthralling class of materials able to engineer functional properties of transition metal oxides widely used in energy and information technologies. In particular, it has been proven that strain‐induced defects in grain boundaries of manganites deeply impact their functional properties by boosting their oxygen mass transport while abating their electronic and magnetic order. In this work, the origin of these dramatic changes is correlated for the first time with strong modifications of the anionic and cationic composition in the vicinity of strained grain boundary regions. We are also able to alter the grain boundary composition by tuning the overall cationic content in the films, which represents a new and powerful tool, beyond the classical space charge layer effect, for engineering electronic and mass transport properties of metal oxide thin films useful for a collection of relevant solid‐state devices.
3D‐Printed Mechanical Metamaterials with High Energy Absorption
Authors: Yuan Shangqin , Chua Chee Kai , Zhou Kun
Published: December 2018

Recently, 3D metamaterials have been achieved with inaccessible mechanical properties in natural materials such as negative Poisson's ratio, stiffness, and thermal expansion coefficient. While most of the developed metamaterials are with engineerable deformation evolution of structures, few studies have revealed their potential in energy absorption due to the limited mechanical properties of 3D‐printed constituent materials and inevitable structural defects induced by the manufacturing process. Herein, an approach is proposed for creating 3D metamaterials of auxetic composite lattices via laser‐sintering of carbon nanotubes reinforced nanocomposites, which provide a platform for the design and manufacturing of systems with programmable energy absorption capability. The optimization of constituent material and structural design enables the improvement of energy absorption performance across multiple scales. The energy absorption capacity of auxetic metamaterials was exponentially scaled with the relative density with the order of 2.5–3. The rationally topologized auxetic metamaterials exhibit a combination of high specific densification strength (0.0195 MPa kg−1 m−3), ultrahigh energy absorption capacity (6.29 MJ m−3), and excellent specific energy absorption (20.42 J g−1). Impressively, this group of auxetic metamaterials possesses the advantageous specific energy absorption approaching that of titanium alloy foams as well as over a broad range of materials including plastic foams, aluminum alloy foams, and other 3D‐printed lightweight structures.
A Wearable Second Skin‐Like Multifunctional Supercapacitor with Vertical Gold Nanowires and Electrochromic Polyaniline
Authors: An Tiance , Ling Yunzhi , Gong Shu , Zhu Bowen , Zhao Yunmeng , Dong Dashen , Yap Lim Wei , Wang Yan , Cheng Wenlong
Published: December 2018

An ideal wearable/implantable bio‐diagnostics can be powered by second skin‐like energy devices in that they offer advantages such as conformal attachment/integration, lightweightness, and moduli‐matching properties. Past several years have witnessed encouraging progresses in soft stretchable supercapacitors by various material combinations and design strategies; however, it remains nontrivial to achieve highly flexible high‐performance supercapacitors in a skin‐thin layout yet with multifunctionality. Here, such a second skin‐like electrochromic supercapacitor is demonstrated using self‐assembled vertical gold nanowires (v‐AuNWs) and electrodeposited polyaniline (PANI). The v‐AuNW film is highly conductive yet offers great flexibility and deformability, while PANI plays a dual role in enhancing capacitance and as charge/discharge‐level indicator. The assembled supercapacitors offer superior skin‐conformability and could achieve an areal specific capacitance of 11.76 mF cm−2 (scan rate of 10 mV s−1) with high durability. A second skin‐like wearable tattoo energy device can be designed with negligible performance deterioration under multiple hand movements and skin deformations.
Hybrid Additive Manufacturing Method for Selective Plating of Freeform Circuitry on 3D Printed Plastic Structure
Authors: Li Ji , Wang Yang , Xiang Gengzhao , Liu Handa , He Jiangling
Published: December 2018

This work proposes a hybrid additive manufacturing method coupling the advantages of dual‐material fused deposition modeling (FDM) 3D printing and selective electroless plating. The method relies on the selective sensitization/activation and metallization of dual‐material FDM 3D printed structure. High‐conductive nickel alloy can only be deposited on the platable plastic surface leaving the nonplatable plastic bare. The study reveals that a combination of acrylonitrile‐butadiene‐styrene and polyethylene terephthalate glycol‐modified materials provides the best metallization selectivity and film adhesion strength. The effects of electroless plating parameters such as temperature, pH value, and duration on the electrical conductivity of metallic film are systematically investigated. Through four‐point probe measurement, energy‐dispersive X‐ray spectroscopy inspection, and scanning electron microscopy cross‐section analysis, it is found that the metal deposition rate majorly depends on the plating temperature, while the composition of plated film is mainly determined by the pH value. Thus, the conductivity of metallic film can be customized according to the detailed requirements of practical applications. A minimal resistivity of 6.7 × 10−5 Ω cm is obtained when electrolessly plated at 50 °C and pH 9. A light‐emitting diode (LED) blinking circuitry is fabricated in both 2D and 3D manners as demonstrators to prove the feasibility and potential of this technology in industry applications.
Controlled Nonvolatile Transition in Polyoxometalates‐Graphene Oxide Hybrid Memristive Devices
Authors: Chen Xiaoli , Zhu Xin , Zhang Shi‐Rui , Pan Jingyi , Huang Pu , Zhang Chen , Ding Guanglong , Zhou Ye , Zhou Kui , Roy Vellaisamy A. L. , Han Su‐Ting
Published: December 2018

Graphene oxide (GO)‐based nonvolatile memory has triggered tremendous interest owing to its high mechanical flexibility, high optical transparency, low cost fabrication, and environmental friendly manufacture for future flexible and transparent electronic devices. Although various data storage types with different switching mechanisms have been demonstrated, challenges still exist in controlling of the memory performances. Here, polyoxometalates (POMs), a type of molecular oxide cluster, is coassembled into the GO‐based memory through electrostatic layer‐by‐layer deposition approach. Assisted by the catalytic activity of POMs, the GO can be reduced to reduced graphene oxide (RGO) under UV irradiation. By this catalytic photoreduction reaction, two types of memory characteristics can be obtained including the write‐once‐read‐many‐times (WORM) derived from the GO‐based memory and the rewritable bipolar resistive switching arising from the RGO‐based counterpart. It was verified that the transition between the WORM and bipolar resistive switching is associated with the modulation of the interface barrier of POM and GO junction. Furthermore, charge trapping/detrapping process is proposed to account for the mechanism of the two memory types. This work offers valuable insight into the new design of tunable memory characteristics and emphasizes the significant role of POMs in modifying the interface features.
2D Perovskite‐Based Self‐Aligned Lateral Heterostructure Photodetectors Utilizing Vapor Deposition
Authors: Hwang Bohee , Lee Jang‐Sik
Published: December 2018

2D organic–inorganic hybrid perovskites (OIPs) hold great promise for electronics and optoelectronics due to structural diversity, high photoluminescence, and tunable bandgap. Moreover, integrating 2D OIPs with the 2D materials including graphene, transition metal dichalcogenide, and other OIPs gives opportunities for various options in constructing new types of heterojunctions with novel functionalities such as enhanced charge transport properties or chemical stability. Here, a sequential vapor deposition method is presented to fabricate 2D OIP lateral heterostructure films (C4H9NH3)2PbI4 (BA2PbI4)–(C4H9NH3)2(CH3NH3)Pb2I7 (BA2MAPb2I7) for photodetector applications. The lateral heterostructure is realized using thermal evaporation to deposit lead iodide (PbI2) films, then exploiting vapor transport of organic vapor to form BA2PbI4, BA2MAPb2I7, and self‐aligned lateral heterostructure. A photodetector based on the lateral structure (BA2PbI4–BA2MAPb2I7) shows larger photocurrent and higher on/off ratio (>102) than those of single material‐based devices (BA2PbI4, BA2MAPb2I7). This method to fabricate 2D OIP lateral heterostructure suggests a simple way to synthesize 2D perovskite heterostructure and may open the possibility of 2D OIP perovskites to be integrated in emerging optoelectronic devices.
Expanding clinical phenotype in CACNA1C related disorders: From neonatal onset severe epileptic encephalopathy to late‐onset epilepsy
Authors: Bozarth Xiuhua , Dines Jennifer N. , Cong Qian , Mirzaa Ghayda M. , Foss Kimberly , Lawrence Merritt J. , Thies Jenny , Mefford Heather C. , Novotny Edward
Published: December 2018

CACNA1C (NM_000719.6) encodes an L‐type calcium voltage‐gated calcium channel (Cav1.2), and pathogenic variants have been associated with two distinct clinical entities: Timothy syndrome and Brugada syndrome. Thus far, CACNA1C has not been reported as a gene associated with epileptic encephalopathy and is less commonly associated with epilepsy. We report three individuals from two families with variants in CACNA1C. Patient 1 presented with neonatal onset epileptic encephalopathy (NOEE) and was found to have a de novo missense variant in CACNA1C (c.4087G>A (p.V1363M)) on exome sequencing. In Family 2, Patient 2 presented with congenital cardiac anomalies and cardiomyopathy and was found to have a paternally inherited splice site variant, c.3717+1_3717+2insA, on a cardiomyopathy panel. Her father, Patient 3, presented with learning difficulties, late‐onset epilepsy, and congenital cardiac anomalies. Family 2 highlights variable expressivity seen within a family. This case series expands the clinical and molecular phenotype of CACNA1C‐related disorders and highlights the need to include CACNA1C on epilepsy gene panels.
Chemo‐ and Regioselective Dihydroxylation of Benzene to Hydroquinone Enabled by Engineered Cytochrome P450 Monooxygenase
Authors: Zhou Hangyu , Wang Binju , Wang Fei , Yu Xiaojuan , Ma Lixin , Li Aitao , Reetz Manfred T.
Published: December 2018

Hydroquinone (HQ) is produced commercially from benzene by multi‐step Hock‐type processes with equivalent amounts of acetone as side‐product. We describe an efficient biocatalytic alternative using the cytochrome P450‐BM3 monooxygenase. Since the wildtype enzyme does not accept benzene, a semi‐rational protein engineering strategy was developed. Highly active mutants were obtained which transform benzene in a one‐pot sequence first into phenol and then regioselectively into HQ without any overoxidation. A computational study shows that the chemoselective oxidation of phenol by the P450‐BM3 variant A82F/A328F leads to the regioselective formation of an epoxide intermediate at the C3=C4 double bond, which departs from the binding pocket and then undergoes fragmentation in aqueous medium with exclusive formation of HQ. As a practical application, an E. coli designer cell system was constructed, which enables the cascade transformation of benzene into the natural product arbutin, which has anti‐inflammatory and anti‐bacterial activities.
Hydrogels based on chitosan in tissue regeneration: How do they work? A mini review
Authors: Jiao Jiao , Huang Jinjian , Zhang Zhijun
Published: December 2018

The repair of tissue defects after injury is of significant clinical and research importance. A variety of chitosan‐based hydrogels have been investigated and applied to address this problem. By using different synthetic methods, the hydrogels exhibit distinct physical properties, including porosity, adhesion, and stiffness. These properties are considered important factors affecting cell proliferation and tissue regeneration. Meanwhile, drug delivery and cell delivery are the two main strategies to improve the therapeutic effects of chitosan‐based hydrogels, but the choices of cells or drugs are quite varied and largely depend on the specificity of the treated tissues. The present review summarizes the physicochemical properties of chitosan‐based hydrogels and their influences on cells, and lists specific ways to promote the tissue regeneration in different systems of the human body. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47235.
High capacity natural fiber coated conductive and electroactive composite papers electrode for energy storage applications
Authors: Masood Aneeqa , Shoukat Zahid , Yousaf Zunaira , Sana Maham , Faisal Iqbal M. , Rehman A. R. , Sultana I. , Razaq Aamir
Published: December 2018

Flexible, lightweight, and environment friendly energy storage devices are in high demand of modern disposable technology. This study presents the coating of directly collected lignocelluloses fibers from self‐growing plant, Monochoria vaginalis with conducting layers of polypyrrole and polyaniline. Fabricated paper electrodes were conductive, electroactive, all‐organic constituents, flexible, and can be cut with help of scissor in any shape. Paper electrodes were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis for morphology, structural, and thermal characteristics, respectively. Furthermore, fabricated paper electrodes were characterized by cyclic voltammetry to confirm the electroactive behavior and showed excellent electrochemical performance. Paper sheets comprising lignocelluloses fibers and polypyrrole coating (LC/PPy) were employed as electrodes of symmetric cell and showed specific capacitance of 230.35 Fg−1 at current density 0.25 mA g−1 for LC/PANI, while LC/PPy showed 9.042 W h kg−1 and 91.33 W kg−1 energy density and power density, respectively. This paper electrodes are highly feasible for environmentally safe and flexible energy storage applications, particularly in era of modern disposable technology. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47282.
An overexpressed cytochrome P450 CYP439A1v3 confers deltamethrin resistance in Laodelphax striatellus Fallén (Hemiptera: Delphacidae)
Authors: Miah Mohammad Asaduzzaman , Elzaki Mohammed Esmail Abdalla , Husna Asmaul , Han Zhaojun
Published: December 2018

Deltamethrin resistance in Laodelphax striatellus had been associated with its oxidative detoxification by overexpression of four cytochrome P450 monooxygenases like CYP353D1v2, CYP6FU1, CYP6AY3v2, and CYP439A1v3. The first three P450s have been validated for insecticide‐metabolizing capability and only CYP6FU1 was found to degrade deltamethrin. In this study, an investigation was conducted to confirm the capability of CYP439A1v3 to degrade deltamethrin. The CYP439A1v3 was first expressed in Sf9 cell line and its recombinant enzyme was tested for metabolic activity against different insecticides using substrate depletion assay combined with metabolite identification. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) and carbon monoxide (CO)‐difference spectra analysis showed that the intact cytochrome P450 protein was successfully expressed. Tests with probe substrates proved its enzyme activity, as p‐nitroanisole, ethoxycoumarin, and ethoxyresorufin were preferentially metabolized (specific activity 7.767 ± 1.22, 1.325 ± 0.37, and 0.355 ± 0.37 nmol/min per mg of protein, respectively) while only luciferin‐HEGE was not. In vitro incubation of the recombinant CYP439A1v3 protein with deltamethrin revealed hydroxylation by producing hydroxydeltamethrin. On the contrary, no metabolite/metabolism was seen with nonpyrethroid insecticide, including imidacloprid, buprofezin, chlorpyrifos, and fipronil. To the best of our knowledge, this is the first study to link a CYP450 from family 439 to confer pyrethroid resistance to L. striatellus. This finding should help in the design of appropriate insecticide resistance management for control of this strain of L. striatellus.
Low concentrations of cadmium chloride promotes protein translation and improve cell line productivity
Authors: Mahameed Mohamed , Obiedat Akram , Beck Gad , Johnson Jeffrey C. , Tirosh Boaz
Published: December 2018

Protein translation has emerged as a critical bottleneck for overall productivity of biological molecules. An augmentation of protein translation can be achieved by cell line engineering or by sophisticated vector design. However, for industrial process development purposes, identification of media additives that promote translation will be of great value, obviating the generation of new host platforms. Here, we examined the effect of low cadmium chloride concentrations on protein synthesis and cell line productivity. At low micromolar concentrations, cadmium chloride induced the mTOR pathway and promoted total protein synthesis in HEK 293T and CHO‐K1 cells with minimal toxicity. In a parallel screening of kinase inhibitors for promoting protein expression, we identified the RSK1 inhibitor, BI‐D1870, as having a transcription promoting activity on cytomegalovirus promoter‐driven transgenes. Fed‐batch analyses of CHO‐K1 cells producing the anticoagulant factor tissue plasminogen activator (tPA) demonstrated that inclusion of cadmium chloride alone and particularly in combination with BI‐D1870 improved overall yields of tPA by more than two‐fold with minimal effect on cell growth. We, therefore, underscore the use of cadmium alone and in combination with BI‐D1870 for improving bioproduction yields.
Monitoring of Organic Acids in Ginseng Roots Produced by Conventional and Environmentally Friendly Farming by Gas Chromatography–Mass Spectrometry
Authors: Seo Chan , Kim Donghyun , Kim Youngbae , Lee Hyeon‐Seong , Kim Hyunbin , Park Kyung Wuk , Oh Dong‐Joo , Park Junseong , Yang Deok‐Chun , Paik Man‐Jeong
Published: December 2018

Metabolomic analysis of organic acids has not been performed for evaluation whether ginseng has been cultivated using conventional or environmental‐friendly farming methods. In this study, profiling analysis was conducted for organic acids (OAs) in ginseng roots produced using conventional or environment‐friendly farming methods at five locations in each of five regions. In OA profiles, lactic acid was the most abundant OA in all regions, with the exception for environmentally friendly farmed ginseng in two of the five regions, in which glycolic acid was most abundant OA. OA profiles in all regions showed isocitric acid levels were increased by environment‐friendly cultivation, which suggests metabolic differences associated from farming method, and that isocitric acid might be a useful discriminatory biomarker of environmental‐friendly and conventional cultivation. The results of the present study suggest metabolomic studies of OAs in ginseng roots might be useful for monitoring whether ginseng has been cultivated using conventional or environmentally friendly farming methods.
Analysis of sialic acid levels in Chinese intravenous immunoglobulins by high‐performance liquid chromatography with fluorescence detection
Authors: Ma Li , Zhang Wei , Hou Mingxia , Li Dong , Liu Fengjuan , Du Xi , Jiang Peng , Wang Zongkui , Zhang Rong , Cao Haijun , Ye Shengliang , Li Changqing
Published: December 2018

Intravenous immunoglobulin (IVIg) is increasingly used for the treatment of autoimmune and systemic inflammatory diseases with both licensed and off‐label indications. Recent studies indicated that IVIg‐mediated immunomodulation and anti‐inflammation are closely associated with the IgG sialylation, especially with IgG crystallizable fragment (Fc) sialylation. The sialic acid levels of the IgG molecules and Fc fragments in 12 IVIg preparations from six Chinese manufacturers were evaluated. The Fc fragments were derived from the papain digestion of IVIg, followed by affinity and size exclusion chromatography. The sialic acid levels in Fc fragments and IVIg preparations were determined by high‐performance liquid chromatography with fluorescence detection, after the sialic acid residues were released from the proteins. The results showed that the sialic acid levels in Chinese IVIg preparations ranged from 0.875 (mol/mol IgG) to 1.085 (mol/mol IgG), and the sialic acid levels in Fc fragments were from 0.321 (mol/mol Fc) to 0.361 (mol/mol Fc). Furthermore, the sialic acid levels of IVIg preparations and Fc fragments from different Chinese manufactures were significantly different. These findings will contribute to an increased understanding of Chinese IVIg preparations and the relationship between the sialic acid levels in IVIg preparations and their clinical efficacy in future clinical studies.
Postoperative complications influencing the long‐term outcome of head‐injured patients after decompressive craniectomy
Authors: Di Guangfu , Zhang Yuhai , Liu Hua , Jiang Xiaochun , Liu Yong , Yang Kun , Chen Jiu , Liu Hongyi
Published: December 2018

Objective

Postoperative complications are common in patients who underwent decompressive craniectomy (DC) after traumatic brain injury (TBI). However, little is known about the degree of association between the postoperative complications and the long‐term outcome of adult TBI patients after DC. The aim of this study was to evaluate the risk of postoperative complications that influenced the long‐term outcome of DC in TBI patients.

Method

A total of 121 patients were studied up to 6 months after DC in TBI. The collected data included demographic, clinical and radiological information, postoperative complications, and Glasgow Outcome Scale‐Extended (GOSE) scores at follow‐up 6 months after DC. Based on their GOSE scores, they were divided into two functional groups: favorable (GOSE = 5–8) or unfavorable outcome (GOSE = 2–4) group. The characteristics of the two groups were compared using statistical analysis. Finally, a regression model was established and a receiver operating characteristic (ROC) curve was applied to analyze its performance power.

Results

Of 121 admitted patients, 31 (25.62%) sustained an unfavorable outcome. A logistic regression analysis showed that the presence of Glasgow Coma Scale (GCS) scores on admission (odds ratio [OR] 0.285, p = 0.001), posttraumatic hydrocephalus (PTH) (OR 8.688, p = 0.003), craniectomy site (OR 8.068, p = 0.033), and postoperative progressive hemorrhagic injury (PHI) (OR 6.196, p = 0.026) were independent risk factors that correlated with an unfavorable outcome. Analysis using ROC curves demonstrated that these factors had different accuracies in predicting an unfavorable outcome (AUC = 0.852 for GCS scores on admission; AUC = 0.826 for PTH, AUC = 0.617 for craniectomy site; AUC = 0.616 for postoperative PHI). The performance power of the GCS scores on admission and PTH influenced the patient's outcomes to a similar degree (p = 0.623), and either predicted the outcome better than the craniectomy site or the postoperative PHI (p < 0.05, respectively).

Conclusion

These findings suggest that the occurrence of PTH and postoperative PHI were independently associated with an unfavorable long‐term outcome after DC in patients with TBI. Early prevention and treatment of PTH and postoperative PHI may be beneficial to improve the long‐term outcome, especially in patients with lower admission GCS scores or bilateral DC.
Chemical and Morphological Inter‐ and Intrapopulation Variability in Natural Populations of Gentiana pneumonanthe L.
Authors: Popović Zorica , Krstić‐Milošević Dijana , Stefanović Milena , Matić Rada , Vidaković Vera , Bojović Srđan
Published: December 2018

Inter‐ and intrapopulation variability in six natural populations of the rare species Gentiana pneumonanthe was examined based on morphological and chemical data. Population size and linear morphometric parameters differed significantly among populations, but without a clear connection to habitat conditions, i. e. water supply and light availability. Leaf shape varied from ovate to lanceolate in all populations, and one population was distinctive in having the largest number of leaves of transitional shape. HPLC analyses of six secondary metabolites were performed separately for belowground parts, and aboveground vegetative and reproductive parts of individual plants (6 populations ×7 individuals ×3 plant parts, n=126) in order to examine differences at the population and individual levels. Three secoiridoids (swertiamarin (SWM), sweroside (SWZ), and gentiopicrin (GP)), one xanthone (mangiferin (MGF)), and two flavones (isoorientin (IO) and isovitexin (IV)) were detected and quantified in the analyzed samples: sweroside dominated in the aboveground reproductive part, mangiferin in the aboveground vegetative part, and gentiopicrin in the belowground part. At the population level, differences in contents of the analyzed chemicals among populations were significant only for a few metabolites. At the individual level, a pronounced organ‐dependent distribution of secondary metabolites was revealed. The results of this study contribute to a better understanding of natural variability within populations of the rare and threatened G. pneumonanthe, and provide data on the contents and within‐plant distribution of secondary metabolites, which are important as pharmacologically active compounds and may be useful for further biotechnological procedures regarding this species.
Impact of Tetracationic Calix[4]arene Conformation—from Conic Structure to Expanded Bolaform—on Their Antibacterial and Antimycobacterial Activities
Authors: Mourer Maxime , Duval Raphaël E. , Constant Patricia , Daffé Mamadou , Regnouf‐de‐Vains Jean‐Bernard
Published: December 2018

The four possible conformers of a new tetrakisguanidino calix[4]arene thought to interact deleteriously with bacterial membranes have been synthesized, characterized, and evaluated for their in vitro cytotoxicity and antibacterial activity against various reference Gram‐negative and Gram‐positive bacteria, as well as Mycobacterium tuberculosis. It appears that reversal of at least one phenolic unit results in clear increases in their activities. This can be attributed to the evolution towards bolaform structures, which are able to interact more deeply with the bacterial membrane. Indeed, the 1,3‐alternate conformer 16 exhibits the best antibacterial activity (MIC<1.0 μg mL−1 on Staphylococcus aureus). Moreover, 16 displays very good antibacterial activities against an isoniazid‐resistant strain of M. tuberculosis (MIC=1.2 μg mL−1), associated with the lowest cytotoxicity, thus making it the most potent compound of the series; this could open new ways of research in the field of anti‐infective drug development to meet the huge current demand.
Recognition of ASF1 by Using Hydrocarbon‐Constrained Peptides
Authors: Bakail May , Rodriguez‐Marin Silvia , Hegedüs Zsófia , Perrin Marie E. , Ochsenbein Françoise , Wilson Andrew J.
Published: December 2018

Inhibiting the histone H3–ASF1 (anti‐silencing function 1) protein–protein interaction (PPI) represents a potential approach for treating numerous cancers. As an α‐helix‐mediated PPI, constraining the key histone H3 helix (residues 118–135) is a strategy through which chemical probes might be elaborated to test this hypothesis. In this work, variant H3118–135 peptides bearing pentenylglycine residues at the i and i+4 positions were constrained by olefin metathesis. Biophysical analyses revealed that promotion of a bioactive helical conformation depends on the position at which the constraint is introduced, but that the potency of binding towards ASF1 is unaffected by the constraint and instead that enthalpy–entropy compensation occurs.
Unsupported Ni(Pt‐Pd) Electro‐catalysts Synthesized by Hydrazine Reduction under the Assistance of a Magnetic Field
Authors: Alvarez Andrea E. , Castagna Rodrigo M. , Sieben Juan Manuel , Duarte Marta M. E.
Published: December 2018

The synthesis of unsupported Ni(Pt−Pd) catalysts via a two‐step process under the assistance of a magnetic field in the presence and absence of sodium citrate was investigated. In absence of the complex agent, sandspur‐like (Ni‐SS(PtPd)) particles of about 90 nm with thorns of ca. 40 nm in length were obtained, while in the presence of citrate anion the catalyst showed the occurrence of nanowires (Ni‐NW(PtPd)), with lengths in the range of 1–10 μm formed by grains of about 45 nm in size. The catalysts prepared in‐house were tested for ethanol electro‐oxidation in alkaline medium at room temperature. The activity of Ni‐NW(PtPd) electrode was almost 32 % higher than that of Ni‐SS(PtPd) material, while the poisoning rate was smaller at the same potential range. Hence, considering that both catalysts have practically the same composition, it is interesting to note that Ni‐NW(PtPd), which has the smallest electroactive surface area, is the one that presents the highest activity for the ethanol oxidation reaction (EOR). This result could be attributed to the lattice strain and electronic effects derived from the particle structure and morphology of the particles, and the electron transport rate through the materials.