bluuebunny/crossref_metadata_2025 huggingface dataset:
Preoperative carbohydrate antigen 19‐9 and standard uptake value of positron emission tomography‐computed tomography as prognostic markers in patients with pancreatic ductal adenocarcinoma
Authors: Moon Dokyoon , Kim Hongbeom , Han Youngmin , Byun Yoonhyeong , Choi Yoojin , Kang Jaeseung , Kwon Wooil , Jang Jin‐Young
Published: October 2020

Background

Among various prognostic factors of pancreatic cancer, preoperative clinical information is obtained by imaging modality. This study aimed to evaluate clinical usefulness of preoperative carbohydrate antigen and preoperative standard uptake value in 18F‐fluorodeoxyglucose positron emission tomography as predictive biological markers for resectable pancreatic ductal adenocarcinoma.

Methods

A total of 189 patients with PDAC who underwent preoperative PET–computed tomography were evaluated. Patients underwent neoadjuvant chemotherapy, and R2 resection was excluded. The correlation between SUVmax and clinicopathologic parameters was analyzed. The C‐tree statistical method was used to estimate cutoff values of logCA19‐9 and SUVmax for survival rate. A multivariate analysis was conducted to identify prognostic factors for overall survival.

Results

The median duration of OS was 26 months, and the 5‐year survival rate was 22.4%. The optimal cutoff values for CA19‐9 level was 150 U/mL and SUVmax was 5.5. When subjects were divided into three groups according to the combination of CA19‐9 level and SUVmax from C‐tree (high‐risk group, CA19‐9 > 150 U/mL and SUVmax > 5.5; intermediate‐risk group, CA19‐9 ≤ 150 U/mL and SUVmax > 5.5 or CA19‐9 > 150 U/mL and SUVmax ≤ 5.5; and low‐risk group, CA19‐9 ≤ 150 U/mL and SUVmax ≤ 5.5), there was a significant 5YSR difference (5.6%, 24.3%, and 36.5%, P < .001). The multivariate analysis revealed high SUVmax, high preoperative CA19‐9 level, venous invasion, and adjuvant chemotherapy were prognostic factors of OS.

Conclusions

CA19‐9 and SUVmax are strong prognostic biological factors in resectable PDAC. Moreover, patients with high CA19‐9 level and SUVmax are not indicated for upfront surgery.
Screening and pharmacodynamic evaluation of the antirespiratory syncytial virus activity of steroidal pyridine compounds in vitro and in vivo
Authors: Wang Zhenya , Hou Duoduo , Fang Jieyu , Zhu Li , Sun Yingying , Tan Yayun , Gu Zichen , Shan Lihong
Published: October 2020

Respiratory syncytial virus (RSV) causes serious lower respiratory tract infections and there are currently no safer or more effective drugs available. It is important to find novel medications for RSV infection. A series of steroidal pyridines were synthesized for screening and evaluation of their antiviral activity and investigation of their antiviral mechanism of action. Compound 3l had the highest antiviral activity, with a half‐maximal effective concentration (EC50) of 3.13 μM. Compound 3l was explored for its effects in vitro on RSV 2 h before infection (pretreatment), at the time of infection (competition), and 2 h after infection (postinfection). Toll‐like receptor (TLR)‐3, retinoic acid‐inducible gene (RIG)‐I, interleukin (IL)‐6, and interferon (IFN)‐β were suppressed at the cellular level. Mouse lung tissue was subjected to hematoxylin and eosin (HE) staining and immunohistochemistry, which showed that RSV antigen and M gene expression could be reduced by compound 3l. Decreased expression of TLR‐3, RIG‐I, IL‐6, IFN‐β, and IL‐10 was also found in vivo. The results indicated that compound 3l exerted its antiviral effects mainly through inhibition of viral replication and downregulation of inflammatory factors.
Weak correlation between antibody titers and neutralizing activity in sera from SARS‐CoV‐2 infected subjects
Authors: Criscuolo Elena , Diotti Roberta A. , Strollo Marta , Rolla Serena , Ambrosi Alessandro , Locatelli Massimo , Burioni Roberto , Mancini Nicasio , Clementi Massimo , Clementi Nicola
Published: October 2020

Plenty of serologic tests for severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) have been developed so far, thus documenting the importance of evaluating the relevant features of the immune response to this viral agent. The performance of these assays is currently under investigation. Amongst them, LIAISON® SARS‐CoV‐2 S1/S2 IgG by DiaSorin and Elecsys Anti‐SARS‐CoV‐2 cobas® by Roche are currently used by laboratory medicine hospital departments in Italy and many other countries. In the present study, we firstly compared two serologic tests on serum samples collected at two different time points from 46 laboratory‐confirmed coronavirus disease‐2019 (COVID‐19) subjects. Secondly, 85 negative serum samples collected before the SARS‐CoV‐2 pandemic were analyzed. Thirdly, possible correlations between antibody levels and the resulting neutralizing activity against a clinical isolate of SARS‐CoV‐2 were evaluated. Results revealed that both tests are endowed with low sensitivity on the day of hospital admission, which increased to 97.8% and 100% for samples collected after 15 days for DiaSorin and Roche tests, respectively. The specificity evaluated for the two tests ranges from 96.5% to 100%, respectively. Importantly, a poor direct correlation between antibody titers and neutralizing activity levels was evidenced in the present study. These data further shed light on both potentials and possible limitations related to SARS‐CoV‐2 serology. In this context, great efforts are still necessary for investigating antibody kinetics to develop novel diagnostic algorithms. Moreover, further investigations on the role of neutralizing antibodies and their correlate of protection will be of paramount importance for the development of effective vaccines.
Investigation of NEAT1, IFNG‐AS1, and NRIR expression in Crimean–Congo hemorrhagic fever
Authors: Bayyurt Burcu , Bakir Mehmet , Engin Aynur , Oksuz Caner , Arslan Serdal
Published: October 2020

Crimean–Congo hemorrhagic fever (CCHF), whose causative agent is CCHF orthonairovirus (CCHFV), demonstrates different symptoms in patients. Long noncoding RNAs (lncRNAs) take part in various pathological processes of viral diseases. They are prominent regulators of antiviral immune responses. To our knowledge, this study is the first study to investigate nuclear paraspeckle assembly transcript 1 (NEAT1), interferon (IFN) gamma antisense RNA 1 (IFNG‐AS1), and negative regulator of IFN response (NRIR) expression in CCHF in the literature. We selected these lncRNAs because they are related to IFN signal or IFN‐stimulated genes. We investigated NEAT1, IFNG‐AS1, and NRIR gene expression in patients with CCHF. Total RNA was extracted from blood samples of 100 volunteers and NEAT1, IFNG‐AS1, and NRIR expression were measured using a quantitative real‐time polymerase chain reaction. NRIR expression was statistically significant in cases versus controls (p < .001), fatals versus controls (p < .001), and fatals versus nonfatals (p = .01). Furthermore, NRIR was found statistically significant at some clinical parameters including alanine aminotransferase (p = .03), international normalized ratio (p = .03), prothrombin time (p = .02), and active partial thromboplastin time (p = .01) in CCHF cases. NEAT1 and IFNG‐AS1 expression were downregulated in the case and fatal groups which were compared with controls. Our results demonstrate that NRIR may be important in CCHF pathogenesis and the target of CCHF treatment.
Effects of the extract from peanut meal fermented with Bacillus natto and Monascus on lipid metabolism and intestinal barrier function of hyperlipidemic mice
Authors: Lu Yaqian , Ding Haoyue , Jiang Xiaoyang , Zhang Huiwen , Ma Aiguo , Hu Yingfen , Li Zichao
Published: October 2020

BACKGROUND

Hyperlipidemia is one of the metabolic disorders that poses a great threat to human health. This study is aimed at investigating the potential hypolipidemic properties of extract from peanut meal fermented with Bacillus natto and Monascus in mice fed with a high‐fat diet. Herein, 60 male C57BL/6J mice were randomly divided into six groups: four control groups, comprised of a normal group, a model (M) group, a positive control group (atorvastatin 10 mg kg−1), and a nonfermented peanut meal extract group (150 mg kg−1), and two experimental groups, comprised of a fermented peanut meal extract low‐dose group (50 mg kg−1) and a fermented peanut meal extract high‐dose group (FH, 150 mg kg−1).

RESULTS

Body weight (P = 0.001) and levels of serum total cholesterol (P = 0.007), triacylglycerol (P = 0.040), low‐density lipoprotein cholesterol (P < 0.001), and leptin (P < 0.001) were remarkably decreased in the FH group, whereas the serum high‐density lipoprotein cholesterol levels were increased (P < 0.001) by 78.3% compared with the M group. Ileum tissue stained with hematoxylin and eosin showed that the ileal villus detachments in mice were improved, and the villus height was increased by supplementation with extract from fermented peanut meal. Moreover, the expressions of intestinal ZO‐1 (P = 0.003) and occludin (P = 0.013) were elevated in the FH group, compared with the M group.

CONCLUSION

Extract of peanut meal fermented by B. natto and Monascus can effectively improve hyperlipidemia caused by a high‐fat diet in mice, via regulating leptin and blood lipid levels, and protect the intestinal mucosal barrier, which provides evidence for its anti‐hyperlipidemia effects and is a research basis for potential industrial development. © 2020 Society of Chemical Industry
Treatment outcome of superficial leiomyosarcoma
Authors: Wellings Elizabeth P. , Tibbo Meagan E. , Rose Peter S. , Folpe Andrew L. , Houdek Matthew T.
Published: October 2020

Background

Nonuterine leiomyosarcomas (LMS) are common extremity soft‐tissue sarcomas. Deep LMS are at an increased risk for recurrence; however, few studies have focused on superficial LMS.

Methods

We reviewed the clinicopathological features of 82 patients with a primary superficial LMS. The mean age and follow‐up were 57 ± 15 and 7 ± 5 years. Depth was classified as dermal (based in the skin; n = 35, 43%) and subcutaneous (based below the dermis, above the fascia; n = 47, 57%) on the final resection specimen. Dermal cases were treated with negative margin resection, while subcutaneous tumors were evaluated by a multidisciplinary team for consideration of possible adjuvant therapy.

Results

The 10‐year disease‐specific survival (DSS) for superficial LMS was 90% with no difference (p = .18) in the 10‐year DSS between patients with dermal (100%) and subcutaneous (86%) LMS. All disease recurrences occurred in subcutaneous LMS (17% vs. 0%, p = .02) and subcutaneous tumors had a worse10‐year metastatic free survival (81% vs. 100%, p = .03).

Conclusions

The results of this study suggest that dermal LMS can be managed with a negative margin resection alone. Although the prognosis for patients with subcutaneous LMS is quite favorable, there is some risk for local and distant recurrence, and such patients will benefit from multidisciplinary care.
Performance of a hybrid fine pitch quad flat package mounted with a new flux on printed circuit board in surface insulation resistance test
Authors: Zhou D. , Haseeb A.S.M.A. , Andriyana A. , Wong Y.H. , Sabri M.F.M. , Low B.Y. , Pang X.S. , Eu P.L. , Tan L.C.
Published: October 2020

An innovative hybrid quad flat package is designed recently by incorporating two types of leads with two distinctive shapes: gull wing and J‐lead. These leads are separated into two layers to increase the adjacent space between them. Pure tin is used as the connector finish in the package, while Sn‐3.0 Ag‐0.5Cu solder material with a new flux is printed on the footprint copper pads of printed circuit board to join the hybrid packages on it. As compared to the conventional quad flat package, the design significantly increases the lead count by 50 % and reduces the distance between two types of leads to 0.325 mm, consequently improving the functional capability in a smaller size product. Surface insulation resistance test is conducted according to IPC‐TM‐650 standard to analyse the reliability of the newly designed hybrid quad flat package. The absence of tin whisker and dendrite after the test demonstrates the reliability of this hybrid package product and the new flux applied.
MRI to C‐arm spine registration through Pseudo‐3D CycleGANs with differentiable histograms
Authors: Oulbacha Reda , Kadoury Samuel
Published: October 2020

Purpose

Image‐guided spine surgery increasingly relies on diagnostic MRI for device navigation, as it allows to visualize the nerves and soft tissues during screw insertion in the pedicle region, which is not possible with preoperative CT or cone beam CT. However, registration of MRI to C‐arm images remains difficult due to differences in visible tissue.

Methods

In this paper, we introduce a three‐dimensional/two‐dimensional (3D/2D) registration method of preoperative T2‐weighted MRI of the lumbar spine to C‐arm X‐ray using synthetic CT images. The registration work is based on a pseudo‐3D CycleGAN integrating a new cyclic loss function to ensure consistency in MRI and CT synthesis using differentiable histograms to match the multimodal distributions. The unified framework allows to improve bony tissue inference as opposed to regular 2D CycleGAN for image synthesis. A multiplanar digitally reconstructed radiograph (DRR) registration approach aligns the 3D and 2D images.

Results

Experiments performed on a public dataset of 18 pathological spines yielded a mean dice coefficient of 0.84 ± 0.015 on synthetic CTs. The DRR registration experiments, on the other hand, presented a target localization error of 2.1 ± 0.2mm.

Conclusion

Intensity distributions and voxel‐wise errors in Hounsfield units show encouraging results, illustrating the network's flexibility of producing qualitatively and quantitatively reasonable synthetic CT scans that can be used in a surgical 3D/2D registration framework. These promising results demonstrate the potential of the synthesis tool prior to integration in an image‐guidance system.
A story of diameter, radius, and (almost) Helly property
Authors: Ducoffe Guillaume , Dragan Feodor F.
Published: October 2020

We present new algorithmic results for the class of Helly graphs, that is, for the discrete analogues of hyperconvex metric spaces. Specifically, an undirected unweighted graph is Helly if every family of pairwise intersecting balls has a nonempty common intersection. It is known that every graph isometrically embeds into a Helly graph that makes of the latter an important class of graphs in metric graph theory. We study diameter and radius computations within the Helly graphs, and related graph classes. This is in part motivated by a conjecture on the fine‐grained complexity of these two distance problems within the graph classes of bounded fractional Helly number—that contain as particular cases the proper minor‐closed graph classes and the bounded clique‐width graphs. Note that under plausible complexity assumptions, neither the diameter nor the radius can be computed in truly subquadratic time on general graphs. In contrast to these negative results, we first present algorithms which given an n‐vertex m‐edge Helly graph G as input, compute with high probability (w.h.p.) its radius and its diameter in time (i.e., subquadratic in n + m). Our algorithms are based on the Helly property and on the unimodality of the eccentricity function in Helly graphs: every vertex of locally minimum eccentricity is a central vertex. Then, we improve our results for the C4‐free Helly graphs, that are exactly the Helly graphs whose balls are convex. For this subclass, we present linear‐time algorithms for computing the eccentricity of all vertices. Doing so, we generalize previous results on strongly chordal graphs to a much larger subclass, that includes, among others, all the bridged Helly graphs and the hereditary Helly graphs. Lastly, we derive approximate versions of our results for the class of chordal graphs: with the latter satisfying an almost‐Helly‐type property, and a stronger (induced‐path) convexity property than the C4‐free Helly graphs. For the chordal graphs, we can compute in quasi linear time the eccentricity of all vertices with an additive one‐sided error of at most one, which is best possible under the strong exponential‐time hypothesis. This answers an open question of Dragan. In fact, we obtain this last result as a byproduct from a more general reduction: from diameter computation on chordal graphs to the Disjoint Sets problem. Roughly, it implies that the split graphs are the only hard instances for diameter computation on chordal graphs. We also get from our reduction that on any subclass of chordal graphs with constant VC‐dimension (and so, for undirected path graphs), the diameter can be computed in truly subquadratic time.
Water‐soluble graphene oxides grafted by polyanilines
Authors: Yamaguchi Isao , Hirota Tomohiro , Wang Aohan
Published: October 2020

The treatment of graphene oxide having 4‐aminophenyl groups (GO‐AP) with (NH4)2S2O8 yielded an ammonium radical cation (GO‐AP.+). The radical polymerization of N‐(4‐sulfopropyl)aniline (ANPrSO3H) and copolymerization of ANPrSO3H with aniline (AN) in the presence of GO‐AP.+ yielded water‐soluble GO composites that were grafted with poly(N‐(4‐sulfopropyl)aniline) and poly(N‐(4‐sulfopropyl)aniline‐co‐aniline), namely, GO‐AP‐PANPrSO3H and GO‐AP‐PAN/PANPrSO3H, respectively. The formation of the composites consisted of GO, PAN, and PANPrSO3H chains that were bonded to the amino group of GO‐AP, confirmed by Raman spectroscopy, differential scanning calorimetry, and scanning electron microscopy analyses. The UV‐vis measurements suggested that the polymer chains of the composites were self‐doped by the sulfonic acid group and de‐doped by sodium sulfonation. The composites exhibited photoluminescence resulting from the polymer chain and GO depending on the excitation wavelength. They underwent electrochemical oxidation of the polymer backbone and reduction of the carbonyl groups.
Tensile and morphological properties of nanocrystalline cellulose and nanofibrillated cellulose reinforcedPLAbionanocomposites: A review
Authors: Zaaba Nor Fasihah , Jaafar Mariatti , Ismail Hanafi
Published: October 2020

In recent years, bionanocomposites have received growing attention in science and industry due to their renewability, biodegradability and superior mechanical properties. Nanocellulose is another promising material that use as a reinforcement filler for bionanocomposite materials due to its lightweight, high surface area, high mechanical strength, high aspect ratio and low density. Different nanocellulose loading, sources, surface modification/functionalization and properties of nanocellulose are important in the production of bionanocomposites. In general, nanocellulose reinforced PLA bionanocomposite offers enhancement in tensile strength and elastic modulus. However, only minimal nanocellulose loadings are required for optimal results due to the incompatibility between the hydrophilic nanocellulose and hydrophobic PLA. This paper reviews the sources of nanocellulose and the properties of nanocellulose with a focus on the tensile and morphological properties of PLA bionanocomposites. Applications of nanocellulose in various industries are discussed in this article. This review article provides some important information. First, this study reviewed the application of nanostructured cellulose in biodegradable polymers. There are two types of nanostructured cellulose: nanocrystalline cellulose (NCC) and nanofibrillated cellulose (NFC). Second, the status on articles published on nanocellulose and PLA/nanocellulose over the past 10 years is reported. Third, the authors of this paper implemented a holistic and critical review to provide a comprehensive understanding of the different properties between NCC and NFC, the application of nanocellulose in bionanocomposites, as well as the properties of PLA and PLA bionanocomposites. Moreover, the influence of NCC and NFC on the tensile and morphological properties of bionanocomposites is covered in this article.
Ion separations with membranes
Authors: Tang Chao , Bruening Merlin L.
Published: October 2020

Ion separations are important for resource recovery, water treatment, and energy production and storage. Techniques such as chemical precipitation, selective adsorption, and solvent extraction are effective, but membranes may separate ions continuously with less waste and lower energy costs. Separation of monovalent and multivalent ions with nanofiltration or electrodialysis membranes already enables water softening and edible salt purification. Similar membranes are attractive as separators in vanadium redox flow batteries. Selective partitioning of divalent counter‐ions into ion‐exchange membranes even allows transport of these ions against their concentration gradients in salt mixtures. However, separations of ions with the same charge is more challenging. Recent research demonstrated highly selective ion “sieving” at small scales. Separations using electrical potentials and differences in ion electrophoretic mobilities are promising, but relatively unexplored. Carrier‐mediated transport affords high selectivity in liquid membranes, but these systems are not very stable, and selective transport via hopping between anchored carriers has proven elusive. Finally, this paper discusses how concentration polarization decreases selectivities in many membrane processes. Although development of selective, inexpensive ion‐separation membranes is a work in progress, successes in water softening and edible salt purification suggests that future selective membranes will serve as complementary methods to traditional purification techniques.
Exploring attitudes about developing cancer among patients with pre‐existing mobility disability
Authors: Agaronnik Nicole D. , El‐Jawahri Areej , Iezzoni Lisa I.
Published: October 2020

Objective

Mobility disability affects approximately 13.7% of the United States population, representing the most common disability type. People with mobility disability experience disparities in cancer screening and higher prevalence of some cancers compared to the general population. We sought to explore the attitudes of people with pre‐existing mobility disability about their cancer diagnosis.

Methods

We conducted open‐ended individual interviews with 20 participants who had pre‐existing mobility disability requiring use of an assistive device or assistance with performance of activities of daily living (ADLs), subsequently diagnosed with cancer (excluding skin cancers). Interviews reached data saturation and were transcribed verbatim for conventional content analysis.

Results

Concerns coalesced around three major themes: sense of control over health conditions, seeking support, and recommendations for other people with disability seeking cancer care. Some participants described feeling a loss of control over their cancer diagnosis that they did not have regarding disability, while others suggested that disability presented greater challenges than their cancer diagnosis. Participants described seeking various forms of support, including emotional support (e.g., from friends and family), informational support (e.g., recommendations for seeking care), instrumental support (e.g., ADLs), and appraisal (e.g., self‐reflection of personal qualities for fighting cancer). They provided recommendations, highlighting importance of self‐advocacy and being attuned to changes in health status.

Conclusions

We found that people with pre‐existing mobility disability and cancer express complex attitudes towards their cancer diagnosis. Findings may inform efforts to improve quality of relevant supports to meet the psychosocial needs of this population.
Further thermo‐stabilization of thermophilic rhodopsin from Thermus thermophilusJL‐18 through engineering in extramembrane regions
Authors: Akiyama Tomoki , Kunishima Naoki , Nemoto Sayaka , Kazama Kazuki , Hirose Masako , Sudo Yuki , Matsuura Yoshinori , Naitow Hisashi , Murata Takeshi
Published: October 2020

It is known that a hyperthermostable protein tolerable at temperatures over 100°C can be designed from a soluble globular protein by introducing mutations. To expand the applicability of this technology to membrane proteins, here we report a further thermo‐stabilization of the thermophilic rhodopsin from Thermus thermophilus JL‐18 as a model membrane protein. Ten single mutations in the extramembrane regions were designed based on a computational prediction of folding free‐energy differences upon mutation. Experimental characterizations using the UV‐visible spectroscopy and the differential scanning calorimetry revealed that four of ten mutations were thermo‐stabilizing: V79K, T114D, A115P, and A116E. The mutation‐structure relationship of the TR constructs was analyzed using molecular dynamics simulations at 300 K and at 1800 K that aimed simulating structures in the native and in the random‐coil states, respectively. The native‐state simulation exhibited an ion‐pair formation of the stabilizing V79K mutant as it was designed, and suggested a mutation‐induced structural change of the most stabilizing T114D mutant. On the other hand, the random‐coil‐state simulation revealed a higher structural fluctuation of the destabilizing mutant S8D when compared to the wild type, suggesting that the higher entropy in the random‐coil state deteriorated the thermal stability. The present thermo‐stabilization design in the extramembrane regions based on the free‐energy calculation and the subsequent evaluation by the molecular dynamics may be useful to improve the production of membrane proteins for structural studies.
A standardized extract of Danggui Buxue Tang decoction selectively exerts estrogenic activities distinctly from tamoxifen
Authors: Zhou Liping , Wong Ka‐Ying , Cao Sisi , Poon Christina Chui‐Wa , Yu Wenxuan , Dong Xiaoli , Tsim Karl Wah‐Keung , Wong Man‐Sau
Published: October 2020

More and more menopausal women use Danggui Buxue Tang (DBT) for relieving their symptoms. Concerns for its safety have been raised as it contains phytoestrogen and acts via estrogen receptors (ERs). Our study aimed to determine whether DBT could selectively exert estrogenic activities and interact with tamoxifen in bone, brain, uterus, and breast by using ovariectomized (OVX) rats and ER‐positive cells. In OVX rats, DBT induced a 31.4% increase in bone mineral density and restored the mRNA expression of dopamine biomarker in striatum, 3.32‐fold for tyrosine hydrolase (p < .001) and 0.21‐fold for dopamine transporter (p < .001), which was similar to tamoxifen; tamoxifen, but not DBT, increased uterus weight and Complement component 3 expression by more than twofold (p < .001); unlike tamoxifen, DBT induced mild proliferation in mammary gland. Two‐way ANOVA indicated the interactions between them in OVX rats (p < .05) but DBT did not alter the responses to tamoxifen. DBT stimulated proliferation or differentiation and estrogen response element in MCF‐7, MG‐63, Ishikawa, and SHSY5Y cells and altered the effects of tamoxifen. In summary, DBT exerted estrogenic effects in tissue‐selective manner, which was different from tamoxifen. DBT interacted with tamoxifen but did not significantly alter its effects in OVX rats.
In vitro reactions of a cyanocobalamin–cisplatin conjugate with nucleoside monophosphates
Authors: Ventura Giovanni , Calvano Cosima Damiana , Losito Ilario , Viola Andrea , Cinquepalmi Valeria , Cataldi Tommaso R.I.
Published: October 2020

Rationale

Cisplatin (CP) is a widely used anticancer drug characterized by toxic side effects that could be alleviated using novel delivery systems including CP prodrugs. The in vitro incubation of a putative prodrug, obtained from cyanocobalamin (CNCbl) and cis‐diamminemonochloroplatinum(II) (mCP), with nucleoside monophosphates (NMPs) was investigated.

Methods

The in vitro reactions between the putative prodrug CNCbl‐mCP and the NMPs of adenosine (AMP), guanosine (GMP), cytidine (CMP) and uridine (UMP) were carried out in slightly acidic water–methanol solutions at 37°C for 24 h. Each sample was examined using reversed‐phase liquid chromatography coupled with electrospray ionization in positive ion mode and tandem mass spectrometry (RPLC/ESI‐MS/MS) by collision‐induced dissociation in a linear ion‐trap mass spectrometer.

Results

Seven adducts were recognized as formed by substitution reactions of the chloride ligand in planar CP. Comparison between observed and theoretical isotopic patterns together with MS/MS fragmentation pathways revealed the presence of single or multiple binding sites depending on the NMP involved. The CNCbl‐mCP conjugate was found to interact with N7 or O4 atoms of GMP and UMP, respectively, generating single adducts, while two isomeric adducts were observed for CMP. Finally, AMP gave rise to three isomeric adducts.

Conclusions

In agreement with literature data relevant to the interaction between CP and NMPs, the most reactive nucleotides were AMP and GMP. The present RPLC/ESI‐MS/MS approach is very promising for investigation of the reactions of CP conjugates with ribonucleotides not only in vitro but also in vivo.
Finite‐time adaptive control of high‐order nonlinear systems with unknown control coefficients and actuator fault
Authors: Ma Jiali , Park Ju H. , Xu Shengyuan
Published: October 2020

In this article, the global finite‐time adaptive control problem is considered for high‐order nonlinear systems in the presence of unknown control coefficients, actuator fault, and external disturbance. Different from the previous results, a tune parameter is introduced to directly compensate the unknown control coefficients rather than the traditional Nussbaum‐gain function. Without requiring a priori knowledge of the uncertainties, a switching‐type adaptive controller is proposed by adding a power integrator method. Based on the modified switching mechanism, the controller parameter can be tuned online such that global finite‐time stability can be achieved. Finally, a simulation example combined with comparison is provided to verify the effectiveness of the proposed method.
Investigating the Cognitive Affective Engagement Model of Learning From Multiple Texts: A Structural Equation Modeling Approach
Authors: List Alexandra
Published: October 2020

Given limited work modeling the role of individual difference factors and processing variables in students’ learning from multiple texts, the author evaluates such a model. In particular, the model analyzed examines the relation between cognitive (i.e., habits with regard to information evaluation) and affective (i.e., interest) individual difference factors and multiple‐text outcomes (i.e., integrated mental model development and intertext model development, as facets of multiple‐text integration), as mediated by students’ processing of multiple texts (i.e., time on texts, engagement in cross‐textual elaboration). Interest and time devoted to text access were found to have a direct effect on integrated mental model formation, whereas time and students’ engagement in cross‐textual elaboration had a direct effect on intertext model development. Additionally, time on texts mediated the relation between both individual difference factors and the integration‐related outcomes examined. Implications for theory development and research on learning from multiple texts are discussed.
An Efficient Environmentally Friendly Composite Material Based on Carbonized Biological Cellulose/Paraffin: Thermal and Sustainable Properties Analysis
Authors: Xu Yunfei , Zhang Xiaoguang , Huang Zhaohui , Chen Guo , Leng Guoqin , Lin Fankai , Zhang Weiyi , Liu Yangai , Fang Minghao , Wu Xiaowen , Min Xin
Published: October 2020

A shape‐stabilized composite phase change material (SS‐CPCM) with paraffin (PA) and biological porous carbon (BPC) was prepared. Freeze‐dried biological‐cellulose include abandoned pomelo peel (APP) and tangerine peel (ATP) were carbonized in vacuum at 800 °C to obtain BPC to be used as a matrix material to prevent PA leakage and enhance thermal conductivity. A vacuum impregnation process was utilized to obtain the SS‐CPCM. Scanning electron microscopy showed that BPC (carbonized APP is subsequently referred to as BPC1 and carbonized ATP as BPC2) has a porous, honeycomb‐like structure, and that the paraffin encapsulated by the pores is evenly distributed. The SS‐CPCM2 (made from ATP) had the highest thermal conductivity (2.10 W/m K), which is 1.89 and 10 times that of the SS‐CPCM1 (made using APP) and pure PA, respectively. Differential scanning calorimetry and thermo‐gravimetric analysis were applied to determine the thermal performance and thermal reliability of the SS‐CPCM. Therefore, the prepared SS‐CPCM has potential in the field of energy storage.
The Role of Carbon Steel Corrosion Process on CaCO3 Scaling in Deoxidized Oilfield Injection Water
Authors: Pang Lin , Zheng Yugui , Chang Ming , Wang Zhengbin
Published: October 2020

The influencing mechanism of the cathodic and anodic reactions in the corrosion process of carbon steel on CaCO3 scaling was studied by galvanostatic polarization, and explained by potentiodynamic polarization, and electrochemical calculation mathematical analysis on the Oddo‐Tomson saturation index. The results reveal that the increased local pH caused by the higher cathodic current density is the only reason for enhanced CaCO3 scaling. A critical corrosion rate due to the diffusion effect of OH−, above which the corrosion process can enhance the CaCO3 scaling is reported. This research highlights the practical significance of corrosion related critical phenomenon for CaCO3 scaling in the deoxidized oilfield injection water system.
A Green Step to New Monomers and Their Polymerization
Authors: Strehmel Veronika , Strunk David , Heinz Markus , Walther Sebastian
Published: October 2020

Extract obtained from the bark of Betula Pendula was treated with sodium hydroxide solution to obtain 4‐(4‐hydroxyphenyl)butan‐2‐one. New (meth)acrylates were synthesized on the basis of 4‐(4‐hydroxyphenyl)butan‐2‐one. Free radical polymerization of the new (meth)acrylates was compared with that of commercial monomers (e. g. phenyl(meth)acrylate, 2‐phenoxyethyl methacrylate, and benzyl methacrylate) in solution resulting in soluble polymers as expected in all examples. In contrast to this, free radical polymerization of 4‐(4‐acryloyloxyphenyl)butan‐2‐one in bulk resulted in a crosslinked material although an extremely high molecular weight soluble polymer was received in case of bulk polymerization of 4‐(4‐methacryloyloxyphenyl)butan‐2‐one. The 3‐oxobutyl substituent at the phenyl ring of these monomers may influence their radical polymerization. Furthermore, enzyme mediated radical polymerization and photoinitiated polymerization were applied for the polymer synthesis using 4‐(4‐methacryloyloxyphenyl)butan‐2‐one.
Green Bio‐organic and Recoverable Catalyst Taurine (2‐aminoethanesulfonic acid) for Synthesis of Bio‐active Compounds 3,4‐Dihydropyrimidin Derivatives in Aqueous Medium.
Authors: Abd El Aleem Ali Ali El‐Remaily Mahmoud , Elhady Omar M.
Published: October 2020

A highly green bio‐organic catalyst known as Taurine (2‐aminoethanesulfonic acid) is plentifully in the tissues of humans and animals and is an efficient and environmentally benign catalyst for the one‐pot multicomponent reaction synthesis of bio‐active 3,4‐dihydropyrimidin‐2(1H)‐ones/thiones (Biginelli Reaction) in aqueous medium. The advantages of this protocol by way of the Taurine catalyst are that it is eco‐friendly, commercially available, low cost, has high reusability, short reaction times, high yields and the products obtained high purities without using any organic solvents.
A Phthalonitrile Resin with a Low Melting Point and High Storage Modulus Containing High‐Density Aromatic Ether Bonds
Authors: Shi Xiaoyu , Bai Shengnan , Ji Puguang , Naito Kimiyoshi , Yu Xiaoyan , Zhang Qingxin
Published: October 2020

A low melting point phthalonitrile monomer named 4,4′‐((((((2‐cyano‐1,3‐phenylene)bis(oxy))bis(4,1‐phenylene))bis(oxy))bis(4,1‐phenylene))bis(oxy))diphthalonitrile (BOPN), was synthesized by nucleophilic substitution of 4,4′‐oxydiphenol with 2,6‐dichlorobenzonitrile. The BOPN resin containing high‐density aromatic ether bonds were prepared via bulk addition polymerization. Two kinds of polymers were prepared from BOPN monomer by using 4‐(aminophenoxy)phthalonitrile (APPH) as the curing agent under different curing procedures. The chemical structure of the monomer was determined by Nuclear Magnetic Resonance spectroscopy (NMR) and Fourier Transform Infrared spectroscopy (FTIR). Dynamic Mechanical Analysis (DMA) demonstrated that the storage modulus of the resin at room temperature was 3712 MPa and the glass transition temperature was above 400 °C. Differential Scanning Calorimetric (DSC) analysis and rheological test indicated that the melting point and processing window of the monomer were 92 °C and 118 °C, respectively. The temperature for 95 % weight retention of the polymer in air was 529 °C.
Exploring the Potential of Supported Ionic Liquids as Building Block Systems in Catalysis
Authors: Kaur Pawanpreet , Chopra Harish K.
Published: October 2020

Supported ionic liquid catalysts have gained significant attention in recent years to overcome the limitations of the homogeneous and heterogeneous catalysis. The thin film containing dispersed homogeneous catalyst in the ionic liquid have been immobilized onto various porous solid supports having a high surface area to synthesize supported ionic liquids (SILs) that acted as potential organocatalysts in organic green synthesis. Support materials, ionic liquids, and molecularly dispersed catalysts have played a significant role in increasing the catalytic activity of the SIL catalysts. In the present review, the literature of the last decade concerning the synthesis of SIL catalysts by using different strategies as well as their applications in organic synthesis is incorporated. The main emphasis of the present work is to critically analyze the recent developments in the supported molecular dispersed catalysts (such as lewis acids, organometallic complexes, metal nanoparticles, and chemical functionality associated with cation/anion of ionic liquids) using ILs and explore their potential to act as building block systems in catalysis.
Synthesis of New Picolylamine Bearing Calix[8]arene Derivatives as Antiproliferative Agents for Colorectal Carcinoma
Authors: Oguz Mehmet , Gul Alev , Karakurt Serdar , Yilmaz Mustafa
Published: October 2020

Calixarene macromolecules have been developed as essential candidate in pharmaceutical application as drug carrier. Possible functionalization with different small molecules at lower and upper rims uplifts biological activity in its structure. This work explain the application of lower rim‐functionalized 4‐picolylamine‐calix[8]arenes (O‐1 b and O‐2 b) in antiproliferative potentials of several human cancerous cells (DLD‐1, HT‐29, MDA‐231, and PC‐3) as well as healthy epithelium cell (PNT1 A). The death mechanism and DNA interaction of O‐1 b and O‐2 b were also investigated. Syntheses of 4‐picolylamine‐calix[8]arenes (O‐1 b and O‐2 b) confirmed with different spectroscopic techniques including 1H NMR, 13C NMR, elemental analysis and FTIR. Results demonstrated that O‐1 b and O‐2 b compounds dose‐dependently inhibited proliferation of DLD‐1, HT‐29, MDA‐231, and PC‐3 cells. The highest cytotoxicity was observed on colorectal carcinoma cells; DLD‐1 with an IC50 value as 4.96 μM and 6.12 μM, respectively. These compounds were weak inhibitors on human healthy epithelium (PNT1 A) cells, while they significantly increased the apoptosis by interacting DNA molecule in a different manner. This is the first study to clarify the molecular mechanism of 4‐picolylamine derived calix[8]arene on human cancerous cells.
Synthesis of New Energetic Materials Based on Furazan Rings and Nitro‐NNO‐azoxy Groups
Authors: Leonov Nikita E. , Klenov Michael S. , Anikin Oleg V. , Churakov Aleksandr M. , Strelenko Yurii A. , Voronin Alexey A. , Lempert David B. , Muravyev Nikita V. , Fedyanin Ivan V. , Semenov Sergei E. , Tartakovsky Vladimir A.
Published: October 2020

Energetic compounds 1–6, consisting of one or two furazan rings linked by azo or azoxy bridges and one or two nitro‐NNO‐azoxy substituents, were synthesized by nitration of the corresponding tert‐butyl‐NNO‐azoxy precursors with NO2BF4. Novel methods for the synthesis of 3,4‐bis(tert‐butyl‐NNO‐azoxy)furazan (7) and bis‐4,4′‐(tert‐butyl‐NNO‐azoxy)‐3,3′‐azoxyfurazan (21) were elaborated. The nitro‐NNO‐azoxy compounds obtained display high calculated detonation performance (vD=8.07–9.40 km s−1 and PC‐J=27.4–43.4 GPa) that is superior to the corresponding nitrofurazans (DNF, DNAzF, DNAF). The replacement of nitrofurazans with the corresponding (nitro‐NNO‐azoxy)furazans increases the specific impulse of the model solid composite propellant formulations by 2–10 s, which is due to high calculated heats of formation (600–892 kcal kg−1) and positive oxygen balance (0–20 %) of the latter compounds.
Sodium and Sulfur Co‐Doped Graphitic Carbon Nitride: A Novel and Effective Visible Light Driven Photocatalyst with Tunable Bandgap for Degradation of Eosin Yellow
Authors: Das Bishal , Devi Meghali , Hassan Barbhuiya Monjur , Sankar Dhar Siddhartha
Published: October 2020

A novel Na and S co‐doped g‐C3N4 (Na−S−GCN) hybrid was synthesized by facile and inexpensive calcination of melamine and Na2S. The synthesized catalysts were systematically characterized with XRD, FT‐IR, SEM, HR‐TEM, XPS, PL and UV‐DRS. The successful doping of Na and S in the g‐C3N4 layers was confirmed with XPS and FT‐IR analysis. UV‐DRS spectra and band gap calculation revealed higher visible light absorption and lower band gap of Na−S−GCN (2.64 eV) than that of GCN (2.83 eV). The photochemical efficiency of Na−S−GCN was examined using eosin yellow (EY) which afforded 90 % degradation in 140 minutes under visible light. A 7.4 times higher degradation of EY was found with Na−S−GCN than that with bulk GCN. The higher catalytic activity was attributed to enhanced visible light absorption and effective lowering of recombination of reactive photogenerated species. The involvement of .OH and O2.− in the degradation process was confirmed with radical trapping experiments.
The Adsorption of Chlorofluoromethane on Pristine, Al‐, Ga‐, P‐, and As‐doped Boron Nitride Nanotubes: A PBC‐DFT, NBO, and QTAIM Study
Authors: Doust Mohammadi Mohsen , Abdullah Hewa Y.
Published: October 2020

The feasibility of detecting a Chlorofluoromethane (CFM) gas molecule on the outer surface of a pristine single‐walled boron nitride nanotube as well as Al‐, Ga‐, P‐, and As‐doped structures. A periodic boundary condition (PBC), within a density functional theory (DFT) method, using the Perdew, Burke, and Ernzerhof exchange‐correlation (PBE0) functional, together with a 6‐311G(d) basis set was used. Subsequently, the B3LYP, CAM−B3LYP, ωB97XD, and M06‐2X functionals were also employed to consider the single point energies. Natural bond orbital (NBO) and quantum theory of atoms in molecules (QTAIM) were implemented by using the PBE0/6‐311G(d). To explore the nature of the intermolecular interactions, density of state (DOS), Wiberg bond index (WBI), natural charge, natural electron configuration, donor–acceptor natural bond orbital interactions, the second‐order perturbation energies tests, and noncovalent interaction (NCI) analysis are performed. The sensitivity of the adsorption will be increased when the gas molecule interacts with decorated nanotubes; therefore, the change of electronic properties can be used to design suitable nanosensors.
Co/N Co‐doped Micro‐/Mesoporous Carbon Nanospheres as Efficient Oxygen Reduction and Oxygen Evolution Reactions Electrocatalysts
Authors: Guo Weibin , Meng Zihan , Chen Neng , Li Hao , Cai Shichang , Wang Rui , Tang Haolin
Published: October 2020

Developing high efficiency and durability catalysts for the electrocatalytic oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is fundamental to achieve the large‐scale commercial application of fuel cells and metal‐air batteries. Herein, a series of Co−N doped bi‐functional hierarchical porous electrocatalysts were synthesized using polyvinyl pyrrolidone (PVP) as soft template to assist the Zn/Co bimetal Zeolitic Imidazolate Framework (BMZIF) to form micro‐/mesoporous carbon nanospheres via a convenient one‐step solution synthesis method, followed by pyrolysis to form carbon nanospheres catalysts. The as‐prepared Co/N co‐doped carbon exhibits outstanding performances in the ORR and OER due to the formed hierarchical pores architecture and the high surface area. The catalyst displays superior ORR performance with a high half‐wave potential of 0.89 V, and a remarkable long‐term stability in 0.1 M KOH. In addition, the electrocatalyst elicits a low voltage of 1.72 V under the current density of 10 mA cm−2. Moreover, the zinc‐air battery fabricated with P‐CNCo‐3 delivers a power density of 175.1 mW cm−2, a high specific capacity of 791 mAh g−1 and an energy density of 976 Wh kg−1 at 20 mA cm−2.
Electrochemical Fabrication of Ternary Black Ti‐Mo‐Ni Oxide Nanotube Arrays for Enhanced Photoelectrochemical Water Oxidation
Authors: Deyab Nourhan M. , Salem Kholoud E. , Mokhtar Abdelrahman M. , Ramadan Mohamed , Steegstra Patrick , Hubin Annick , Delplancke Marie‐Paule , Rahier Hubert , Allam Nageh K.
Published: October 2020

Point defects play important and crucial roles in the design of high performance photocatalysts. We report on the electrochemical fabrication of black Ti−Mo‐Ni−O nanotubes as a promising electrode material for solar‐assisted water splitting. The ternary Ti−Mo‐Ni−O catalyst was annealed in hydrogen atmosphere to induce point defects in the material to enhance its conductivity, charge carriers density, and performance. The effect of annealing duration on the performance of ternary Ti−Mo‐Ni−O nanotube films was investigated. The hydrogen‐annealed nanotubes showed enhanced optical characteristics in the visible spectrum, which can be related to the formation of defect states upon hydrogen annealing. The 10 h‐annealed sample showed an exceptionally enhanced photocurrent density of ∼10 mA/cm2 with a remarkable open‐circuit voltage of ∼−1.0 VAg/AgCl under AM 1.5G illumination. This improved photocurrent is in agreement with the obtained 75 % incident‐photon‐to‐current‐conversion‐efficiency (IPCE), confirming the improved photoactivity of the hydrogen‐treated mixed oxide nanotubes.
Efficacy of Fatty Acid Amide Derivatives against Listeria monocytogenes
Authors: Yosief Hailemichael O. , Hussain Syed A. , Sarker Majher I. , Annous Bassam A.
Published: October 2020

Fatty acid amide derivatives of lauric, myristic and palmitic acids were synthesized and evaluated for their inhibitory activity against the cocktail of four Listeria monocytogenes (LMC) strains. Pyrrolidine amide derivative of Lauric (LAPY) and myristic (MYPY) acids exhibited time and concentration dependent inhibitory activity against LMC but pyrrolidine amide derivative of palmitic acid did not show any inhibitory activity. Treating LCM strains with 15 ppm of LAPY for 2 min resulted in 4.0 log CFU/ml reduction in bacterial count, and when the treatment was extended for 4, 6 and 10 min, the bacterial growth was inhibited completely. Similarly, treating LMC with MYPY resulted in significant log reduction but higher concentration was required compared to LAPY. Both LAPY and MYPY demonstrated remarkable inhibitory activity against LMC strains compared to lauric acid which is known to be active against Listeria and other gram‐positive bacterial strains. To the best of our knowledge, this is the first study to demonstrate that pyrrolidine amide derivative of lauric and myristic acids have excellent inhibitory activity against LMC strains. These fatty acid amide derivatives can be considered as bio‐based antimicrobial agents that can control Listeria growth in food products.