bluuebunny/crossref_metadata_2025 huggingface dataset:
Surface enhanced Raman scattering and quantum‐mechanical calculations on self‐assembling oligopeptides
Authors: Di Foggia Michele , Ottani Stefano , Torreggiani Armida , Zamuner Annj , Dettin Monica , Sanchez‐Cortes Santiago , Cesini Daniele , Tinti Anna
Published: March 2018

The surface‐enhanced Raman scattering spectra of 5 amphiphilic oligopeptides derived from EAK16 (AEAEAKAK)2, used as biomimetic coatings for medical devices, were obtained at 10−5–10−6 M in order to study the effects of systematic amino acid substitution along the peptide chain on the corresponding interaction with Ag colloidal nanoparticles. In addition, quantum‐mechanical data on 2 of the examined peptides were very useful for clarifying the assignment of bands, widely debated in the literature. In general, the peptide–nanoparticles interaction takes place through the COO− groups. The substitution of Ala by 2‐aminobutanoic acid in the sequence, corresponding to an increase of the hydrophobic chain length, is able to affect the peptide–Ag colloid interaction. It strengthens the interaction with NH3+ groups, mediated by the Cl− anions present in the colloidal solution, although the charge transfer interaction with the COO− ions remains the dominant interaction mechanism. When Tyr substitutes the hydrophobic Ala, the interaction mechanism is strongly affected because it takes mainly place through the Tyr residues, where the aromatic rings are predominantly perpendicular to the silver surface, partly as tyrosinate ion. Thus, the addition of the Arg‐Gly‐Asp sequence, useful to provide control on the bioactivity of the bone regeneration materials, does not change the interactions with the colloid, because the spacer amino acid substitution is the main factor affecting the peptide–nanoparticle interactions.
Influence of iron redox state on black ripe olive processing
Authors: García Pedro , Romero Concepción , Brenes Manuel
Published: March 2018

BACKGROUND

The oxidation and polymerization of the phenolic compounds present in black ripe olives give rise to their black shiny colour, which is fixed by the addition of ferrous salts such as ferrous gluconate. Among the many variables that can affect the success of this fixation step, the influence of pH on this process was assessed on fruits of the Hojiblanca cultivar processed at pilot plant scale. Hence the aim of this work was to gain knowledge on the development of this fixation step, in particular on olives that were oxidized with a single alkaline treatment.

RESULTS

It was found that the penetration of the ferric cation into the olive flesh was an extremely slow process and it led to less‐dark olives. Besides, at a pH higher than 6 the oxidation of the ferrous to the ferric cation was a very rapid reaction, and olives that were processed with initial pH adjusted to 4 units had a darker colour than those without pH correction. Ultrafiltration/nanofiltration of oxidized olive solutions spiked with ferric ions or even pure oxidized ferric solutions through membranes of 10, 3 and 1 kDa revealed that ferric ions formed high‐molecular structures that inhibited the penetration of the ion into the olive flesh and therefore the fixation of the black colour.

CONCLUSION

The results presented in this study suggest that the formation of ferric ions during the colour fixation step of black ripe olives must be avoided to obtain darker olives. Consequently, the initial pH of the ferrous gluconate solution must be corrected to avoid oxidation of the ferrous to ferric cations during the fixation step. This study will contribute to the improvement of the colour fixation step of black ripe olive processing. © 2018 Society of Chemical Industry
Intralesional PV‐10 for the treatment of in‐transit melanoma metastases—Results of a prospective, non‐randomized, single center study
Authors: Read Tavis A. , Smith Aaron , Thomas Janine , David Michael , Foote Matthew , Wagels Michael , Barbour Andrew , Smithers B. Mark
Published: March 2018

Background

Patients with in‐transit melanoma metastases frequently experience high rates of recurrence, limited overall survival and reduced quality of life. After promising results within a Phase II, multi‐center study, PV‐10 treatment was continued at our institution for patients with in‐transit disease.

Methodology

An open‐label, non‐randomized, prospective study was performed at the Princess Alexandra Hospital, Queensland, Australia. Patients were treated with PV‐10 in accordance with the treatment protocol established during a previous Phase II study. The primary outcome was the complete response of treated lesions.

Results

Forty‐five patients were enrolled over a total of 82 treatment episodes from July 2008 to December 2015. With sequential PV‐10 treatments the complete response rate was 42% and overall response rate 87% on an intention to treat analysis. The median follow‐up duration was 22 months and the median overall survival was 25 months from first PV‐10 treatment. Having fewer than 15 metastases at the time of treatment was associated with a complete response (P = 0.03).

Conclusions

Intralesional PV‐10 provided rapid lesion‐specific ablation of melanoma metastases with well‐tolerated local effects and minimal systemic adverse events. This therapy should be considered for patients with multiple accessible deposits within the spectrum of low to moderate disease volume.
DNA hydroxymethylation of colorectal primary carcinoma and its association with survival
Authors: Zhong Anjing , Tian Yiping , Zhang Honghe , Lai Maode
Published: March 2018

Methods

A total of 71 cases of colorectal carcinoma with hepatic metastasis were enrolled from the Department of Pathology of SIR RUN RUN SHAW Hospital. Paired primary tumors, hepatic metastases, and normal mucosa samples were collected from formalin‐fixed paraffin‐embedded tissues by manual macrodissection. And global levels of DNA methylation and hydroxymethylation in these tissues, measured by an ELISA‐like microplate‐based colorimetric methods. The immunohistochemical expression of 5‐methylcytosine and 5‐hydroxymethylcytosine were analyzed also.

Results

The levels of DNA methylation in both primary and metastatic tumors were elevated when compared with normal mucosa, while DNA hydroxymethylation decreased slightly in those tissues. Similar results were observed in immunohistochemical staining. DNA methylation in hepatic metastases differed significantly in lymph node metastases (P = 0.037). And DNA hydroxymethylation in colorectal primary carcinoma was significantly different between tumor grade group (P = 0.018) and gender group (P = 0.048) respectively. And survival analyzes revealed that higher levels DNA hydroxymethylation were associated with better prognosis in colorectal primary carcinoma (P < 0.05).

Conclusion

DNA hydroxymethylation correlated with less aggressive tumor behavior in colorectal cancer and were identified as an independent prognostic factor in patients' overall survival, and downregulation of DNA hydroxymethylation may serve as a useful biomarker for colorectal cancer prognosis evaluation.
Simulation of Nonporous Polymeric Membranes Using CFD for Bioethanol Purification
Authors: Asadollahzadeh Mehdi , Raoufi Nahid , Rezakazemi Mashallah , Shirazian Saeed
Published: March 2018

A mechanistic model is developed to simulate ethanol purification using membrane technology. In the considered process, a feed solution containing 10 wt% water + 90 wt% ethanol is contacted with a polymeric dense membrane in a pervaporation system. The membrane selectively separates water from solution in order to purify the ethanol. In the development of the model, it is assumed that the water is the main penetrant through the membrane due to the hydrophilicity of membrane material. The mass fraction of water molecules in the feed solution, as well as membrane, is estimated using Maxwell–Stefan approach. The governing equations are then solved using finite element method in order to predict mass fraction, mass transfer flux, and velocity of the solution in the membrane module. The results indicate that the model can predict the formation of concentration and velocity boundary layer in the feed solution near the membrane/feed interface. Moreover, the developed model is robust and reliable in the understanding of membrane separation processes applicable for dehydration of alcohols.
Oil type and cross‐linking influence growth of Aureobasidium melanogenum on vegetable oils as a single carbon source
Authors: Peeters Loes H. M. , Huinink Hendrik P. , Voogt Benjamin , Adan Olaf C. G.
Published: March 2018

Aureobasidium melanogenum is the main fungus found in a spontaneously formed biofilm on a oil‐treated wood. This dark colored biofilm functions as a protective coating. To better understand biofilm formation, in this study A. melanogenum was cultured on olive oil and raw linseed oil. Metabolic activity and oil conversion were measured. The results show that A. melanogenum is able to grow on linseed oil and olive oil as a single carbon source. The fungus produces the enzyme lipase to convert the oil into fatty acids and glycerol. Metabolic activity and oil conversion were equal on linseed oil and olive oil. The fungus was not able to grow on severe cross‐linked linseed oil, meaning that the degree of cross‐linking of the oil is important for growth of A. melanogenum. Dark coloring of the colony was seen on linseed oil, which might be a stress response on the presence of autoxidation products in linseed oil. The colony on olive oil showed delayed melanin production indicating an inhibitory effect of olive oil on melanin production.
Nickel exposure induces persistent mesenchymal phenotype in human lung epithelial cells through epigenetic activation of ZEB1
Authors: Jose Cynthia C. , Jagannathan Lakshmanan , Tanwar Vinay S. , Zhang Xiaoru , Zang Chongzhi , Cuddapah Suresh
Published: March 2018

Nickel (Ni) is an environmental and occupational carcinogen, and exposure to Ni is associated with lung and nasal cancers in humans. Furthermore, Ni exposure is implicated in several lung diseases including chronic inflammatory airway diseases, asthma, and fibrosis. However, the mutagenic potential of Ni is low and does not correlate with its potent toxicity and carcinogenicity. Therefore, mechanisms underlying Ni exposure‐associated diseases remain poorly understood. Since the health risks of environmental exposures often continue post exposure, understanding the exposure effects that persist after the termination of exposure could provide mechanistic insights into diseases. By examining the persistent effects of Ni exposure, we report that Ni induces epithelial‐mesenchymal transition (EMT) and that the mesenchymal phenotype remains irreversible even after the termination of exposure. Ni‐induced EMT was dependent on the irreversible upregulation of ZEB1, an EMT master regulator, via resolution of its promoter bivalency. ZEB1, upon activation, downregulated its repressors as well as the cell‐cell adhesion molecule, E‐cadherin, resulting in the cells undergoing EMT and switching to persistent mesenchymal status. ZEB1 depletion in cells exposed to Ni attenuated Ni‐induced EMT. Moreover, Ni exposure did not induce EMT in ZEB1‐depleted cells. Activation of EMT, during which the epithelial cells lose cell‐cell adhesion and become migratory and invasive, plays a major role in asthma, fibrosis, and cancer and metastasis, lung diseases associated with Ni exposure. Therefore, our finding of irreversible epigenetic activation of ZEB1 by Ni exposure and the acquisition of persistent mesenchymal phenotype would have important implications in understanding Ni‐induced diseases.
Timosaponin A‐III inhibits oncogenic phenotype via regulation of PcG protein BMI1 in breast cancer cells
Authors: Gergely Joseph E. , Dorsey Armond E. , Dimri Goberdhan P. , Dimri Manjari
Published: March 2018

Polycomb group (PcG) protein BMI1 is an important regulator of oncogenic phenotype and is often overexpressed in several human malignancies including breast cancer. Aberrant expression of BMI1 is associated with metastasis and poor prognosis in cancer patients. At present, therapy reagents that can efficiently inhibit the expression of BMI1 are not very well known. Here, we report that Timosaponin A‐III (TA‐III), a steroidal saponin obtained from the rhizomes of an herb, Anemarrhena asphodeloides, strongly inhibits expression of BMI1 in breast cancer cells. Treatment of breast cancer cells with TA‐III resulted in inhibition of oncogenic phenotypes such as proliferation, migration and invasion, and induction of cellular senescence. Inhibition of these oncogenic phenotypes was accompanied by downregulation of BMI1 expression and histone posttranslational modification activity of PRC1. The mechanistic analysis of TA‐III‐induced inhibition of oncogenic activity and BMI1 expression suggests that downregulation of c‐Myc mediates TA‐III effect on BMI1. We further show that exogenous BMI1 overexpression can overcome TA‐III‐induced inhibition of oncogenic phenotypes. We also show that TA‐III induces expression of tumor suppressive miR‐200c and miR‐141, which are negatively regulated by BMI1. In summary, our data suggest that TA‐III is a potent inhibitor of BMI1 and that it can be successfully used to inhibit the growth of tumors where PcG protein BMI1 and PcG activities are upregulated.
Avenues to molecular imaging of dying cells: Focus on cancer
Authors: Rybczynska Anna A. , Boersma Hendrikus H. , de Jong Steven , Gietema Jourik A. , Noordzij Walter , Dierckx Rudi A. J. O. , Elsinga Philip H. , van Waarde Aren
Published: March 2018

Successful treatment of cancer patients requires balancing of the dose, timing, and type of therapeutic regimen. Detection of increased cell death may serve as a predictor of the eventual therapeutic success. Imaging of cell death may thus lead to early identification of treatment responders and nonresponders, and to “patient‐tailored therapy.” Cell death in organs and tissues of the human body can be visualized, using positron emission tomography or single‐photon emission computed tomography, although unsolved problems remain concerning target selection, tracer pharmacokinetics, target‐to‐nontarget ratio, and spatial and temporal resolution of the scans. Phosphatidylserine exposure by dying cells has been the most extensively studied imaging target. However, visualization of this process with radiolabeled Annexin A5 has not become routine in the clinical setting. Classification of death modes is no longer based only on cell morphology but also on biochemistry, and apoptosis is no longer found to be the preponderant mechanism of cell death after antitumor therapy, as was earlier believed. These conceptual changes have affected radiochemical efforts. Novel probes targeting changes in membrane permeability, cytoplasmic pH, mitochondrial membrane potential, or caspase activation have recently been explored. In this review, we discuss molecular changes in tumors which can be targeted to visualize cell death and we propose promising biomarkers for future exploration.
Towards simulation based mixed‐integer optimization with differential equations
Authors: Gugat Martin , Leugering Günter , Martin Alexander , Schmidt Martin , Sirvent Mathias , Wintergerst David
Published: March 2018

We propose a decomposition based method for solving mixed‐integer nonlinear optimization problems with “black‐box” nonlinearities, where the latter, for example, may arise due to differential equations or expensive simulation runs. The method alternatingly solves a mixed‐integer linear master problem and a separation problem for iteratively refining the mixed‐integer linear relaxation of the nonlinear equalities. The latter yield nonconvex feasible sets for the optimization model but we have to restrict ourselves to convex and monotone constraint functions. Under these assumptions, we prove that our algorithm finitely terminates with a global optimal solution of the mixed‐integer nonlinear problem. Additionally, we show the applicability of our approach for three applications from optimal control with integer variables, from the field of pressurized flows in pipes with elastic walls, and from steady‐state gas transport. For the latter we also present promising numerical results of our method applied to real‐world instances that particularly show the effectiveness of our method for problems defined on networks.
Thyroid cancer in adolescents and young adults
Authors: Massimino Maura , Evans Douglas B. , Podda Marta , Spinelli Claudio , Collini Paola , Pizzi Natalia , Bleyer Archie
Published: March 2018

In adolescents and young adults, thyroid cancer accounts for 13% of all invasive neoplasms, being three times more frequent in females, but overdiagnosis and overtreatment are common. There are two therapeutic approaches, one radical and no longer preferred in all instances, and the other conservative. Permanent complications of surgery and metabolic irradiation can affect quality of life and carry an economic burden. The overall survival rate approaches 100% for patients with differentiated thyroid cancer regardless of the extent of treatment. Medullary thyroid carcinoma is a very different entity, occurring most frequently in the context of hereditary tumor susceptibility syndromes.
Down‐regulation of dishevelled‐2 inhibits cell proliferation and invasion in hepatoblastoma
Authors: Huang Siqi , Chen Jing , Tian Ruicheng , Wang Jing , Xie Chenjie , Gao Hongxiang , Shan Yuhua , Hong Jie , Zhang Zhen , Xu Min , Gu Song
Published: March 2018

Background

Hepatoblastoma (HB) is the most common liver cancer found in early childhood. These patients suffer poor outcomes and need novel therapies. An abnormal activation of Wnt signaling is the hallmark of HB tumorigenesis, and its pathway is a potential candidate for a pharmacological intervention.

Procedure

Tissue samples of patients with HB were collected for RNA‐seq, quantitative real‐time PCR, and immunohistochemistry to identify if disheveled‐2 (Dvl‐2) was a target gene. The correlation between Dvl‐2 expression and different clinicopathological features was analyzed using statistical methods. Proliferation and invasion assays were applied after knocking down Dvl‐2 by shRNA in HepG2 and Huh6 HB cell lines. The antitumor effect of niclosamide on HB was ascertained in vitro and in vivo.

Results

Dvl‐2 was overexpressed in 90% of patients with HB, and Dvl‐2 expression was positively correlated with the age of patients with HB. Knockdown of Dvl‐2 could inhibit proliferation and invasion of HB cell lines. Also, niclosamide, a Food and Drug Administration approved antihelminth compound, could effectively inhibit HB cell growth in vitro and in vivo via downregulation of Dvl‐2 and β‐catenin expression.

Conclusions

Our results implicate that Dvl‐2 is a potential therapeutic target in HB, and niclosamide could have clinical potential to treat patients with HB.
Disease burden and conditioning regimens in ASCT1221, a randomized phase II trial in children with juvenile myelomonocytic leukemia: A Children's Oncology Group study
Authors: Dvorak Christopher C. , Satwani Prakash , Stieglitz Elliot , Cairo Mitchell S. , Dang Ha , Pei Qinglin , Gao Yun , Wall Donna , Mazor Tali , Olshen Adam B. , Parker Joel S. , Kahwash Samir , Hirsch Betsy , Raimondi Susana , Patel Neil , Skeens Micah , Cooper Todd , Mehta Parinda A. , Grupp Stephan A. , Loh Mignon L.
Published: March 2018

Background

Most patients with juvenile myelomonocytic leukemia (JMML) are curable only with allogeneic hematopoietic cell transplantation (HCT). However, the current standard conditioning regimen, busulfan‐cyclophosphamide‐melphalan (Bu‐Cy‐Mel), may be associated with higher risks of morbidity and mortality. ASCT1221 was designed to test whether the potentially less‐toxic myeloablative conditioning regimen containing busulfan‐fludarabine (Bu‐Flu) would be associated with equivalent outcomes.

Procedure

Twenty‐seven patients were enrolled on ASCT1221 from 2013 to 2015. Pre‐ and post‐HCT (starting Day +30) mutant allele burden was measured in all and pre‐HCT therapy was administered according to physician discretion.

Results

Fifteen patients were randomized (six to Bu‐Cy‐Mel and nine to Bu‐Flu) after meeting diagnostic criteria for JMML. Pre‐HCT low‐dose chemotherapy did not appear to reduce pre‐HCT disease burden. Two patients, however, received aggressive chemotherapy pre‐HCT and achieved low disease‐burden state; both are long‐term survivors. All four patients with detectable mutant allele burden at Day +30 post‐HCT eventually progressed compared to two of nine patients with unmeasurable allele burden (P = 0.04). The 18‐month event‐free survival of the entire cohort was 47% (95% CI, 21–69%), and was 83% (95% CI, 27–97%) and 22% (95% CI, 03–51%) for Bu‐Cy‐Mel and Bu‐Flu, respectively (P = 0.04). ASCT1221 was terminated early due to concerns that the Bu‐Flu arm had inferior outcomes.

Conclusions

The regimen of Bu‐Flu is inadequate to provide disease control in patients with JMML who present to HCT with large burdens of disease. Advances in molecular testing may allow better characterization of biologic risk, pre‐HCT responses to chemotherapy, and post‐HCT management.
Acute kidney injury after high dose etoposide phosphate: A retrospective study in children receiving an allogeneic hematopoetic stem cell transplantation
Authors: Barnoud Delphine , Pinçon Claire , Bruno Bénédicte , Béné Johana , Gautier Sophie , Lahoche Annie , Petitpain Nadine , Vasseur Michèle , Barthélémy Christine , Décaudin Bertrand , Simon Nicolas , Odou Pascal
Published: March 2018

Background

Etoposide phosphate (EP; single injection, 60 mg/kg) followed by total body irradiation (TBI) at 12 Gy has been used as an allogeneic stem cell transplantation (allo‐SCT) conditioning regimen for children since 2010. In our institution, EP has been suspected of leading to acute nephrotoxicity. The aim of this study was to assess the potential renal toxicity of EP in this context.

Materials and methods

A retrospective study was carried out on children hospitalized between 2007 and 2015 for allo‐SCT with TBI‐based myeloablative conditioning associated with cyclophosphamide (CY, 60 mg/kg/day × 2 days) or EP. The primary endpoint of the study was the occurrence of acute kidney injury (AKI). Additional endpoints were time to recovery for children with AKI, survival, and treatment‐related mortality.

Results

Thirty‐five patients were analyzed (CY: 22 vs. EP: 13). AKI occurred more frequently in the EP group than in the CY one (69% vs. 27%, adjusted odds ratio 6.0, 95% confidence interval [CI] [1.145; 31.445], P = 0.03). The median time to recovery was estimated at 3 days, 95% CI (2; 17), with CY and 11 days 95% CI (5; 18) with EP (adjusted hazard ratio of recovery for EP vs. CY 0.262, 95% CI [0.071; 0.969], P = 0.04). No significant difference was highlighted between the two treatments for survival or for treatment‐related mortality.

Discussion

This study shows that EP at high dosage or one of its excipients is probably responsible for AKI, as compared to CY. Further studies are required to explore the origin of this adverse effect.
Obesity, sedentary lifestyle, and video games: The new thrombophilia cocktail in adolescents
Authors: Kohorst Mira A. , Warad Deepti M. , Nageswara Rao Amulya A. , Rodriguez Vilmarie
Published: March 2018

Rates of venous thromboembolism have increased in the adolescent population over the last two decades, likely due to advanced diagnostics, increased use of central venous catheters, chronic medical conditions, obesity, and oral contraceptive use. Of these factors, a modifiable risk factor for adolescents is obesity. Sedentary lifestyle and prolonged immobilization are additional prothrombotic risk factors that are often associated with obesity. With ever‐increasing screen time, sedentary behavior has risen accordingly, especially among gamers. We present four cases of adolescents who developed life‐threatening venous thromboembolic events in the setting of obesity, sedentary lifestyle and/or immobilization, and prolonged video game use.
Polypropylene biocomposites reinforced with bamboo particles and ultrafine bamboo‐char: The effect of blending ratio
Authors: Zhang Shen , Yao Wenchao , Zhang Huanhuan , Sheng Kuichuan
Published: March 2018

Bamboo particles (BPs) and ultrafine bamboo‐char (UFBC) were introduced into polypropylene (PP) biocomposites by melt‐blending and injection molding, to improve the mechanical and thermal properties of PP matrix. The maximum tensile strength of 30.59 MPa was obtained when the ratio was 70/25/5, which was improved by 30% than that of pure PP. The maximum tensile modulus of 460.13 MPa was achieved when the ratio was 70/20/10, which was enhanced by 109%, 35% and 24% than that of neat PP, PP/BP (70/30), and PP/UFBC (70/30), respectively. The mechanical and thermal properties of the biocomposites were improved through adding UFBC. Improvement evidences on interfacial interaction and elemental distribution were observed by scanning electron microscope and energy dispersive spectrum analysis. The maximum melting temperature of 166.6°C was achieved that was increased 5.9°C than neat PP. Crystallization temperature was significantly improved with the increasing of UFBC and BP loadings. POLYM. COMPOS., 39:E640–E646, 2018. © 2018 Society of Plastics Engineers
Physiological and iTRAQ‐Based Quantitative Proteomics Analysis of Methyl Jasmonate–Induced Tolerance in Brassica napus Under Arsenic Stress
Authors: Farooq Muhammad Ahsan , Zhang Kangni , Islam Faisal , Wang Jian , Athar Habib U. R. , Nawaz Aamir , Ullah Zafar Zafar , Xu Jianxiang , Zhou Weijun
Published: March 2018

Brassica napus plants exposed to 200 μM arsenic (As) exhibited high‐level of stress condition, which led to inhibited growth, enhanced lipid peroxidation, and disrupted cellular ultrastructures. Exogenous application of methyl jasmonate (MeJA) alleviated the As‐induced oxidative stress and improved the plant growth and photosynthesis. In this study, changes in the B. napus leaf proteome are investigated in order to identify molecular mechanisms involved in MeJA‐induced As tolerance. The study identifies 177 proteins that are differentially expressed in cultivar ZS 758; while 200 differentially expressed proteins are accumulated in Zheda 622, when exposed to As alone and MeJA+As treatments, respectively. The main objective was to identify the MeJA‐regulated protein under As stress. Consistent with this, iTRAQ detected 61 proteins which are significantly accumulated in ZS 758 leaves treated with MeJA under As stress. While in Zheda 622, iTRAQ detected 49 MeJA‐induced proteins under As stress. These significantly expressed proteins are further divided into five groups on the base of their function, that is, stress and defense, photosynthesis, carbohydrates and energy production, protein metabolism, and secondary metabolites. Taken together, this study sheds light on the molecular mechanisms involved in MeJA‐induced As tolerance in B. napus leaves and suggests a more active involvement of MeJA in plant physiological processes.
Quantitative Proteomic Analysis of Staphylococcus aureus Treated With Punicalagin, a Natural Antibiotic From Pomegranate That Disrupts Iron Homeostasis and Induces SOS
Authors: Cooper Bret , Islam Nazrul , Xu Yunfeng , Beard Hunter S. , Garrett Wesley M. , Gu Ganyu , Nou Xiangwu
Published: March 2018

Staphylococcus aureus, a bacterial, food‐borne pathogen of humans, can contaminate raw fruits and vegetables. While physical and chemical methods are available to control S. aureus, scientists are searching for inhibitory phytochemicals from plants. One promising compound from pomegranate is punicalagin, a natural antibiotic. To get a broader understanding of the inhibitory effect of punicalagin on S. aureus growth, high‐throughput mass spectrometry and quantitative isobaric labeling was used to investigate the proteome of S. aureus after exposure to a sublethal dose of punicalagin. Nearly half of the proteins encoded by the small genome were interrogated, and nearly half of those exhibited significant changes in accumulation. Punicalagin treatment altered the accumulation of proteins and enzymes needed for iron acquisition, and it altered amounts of enzymes for glycolysis, citric acid cycling, protein biosynthesis, and purine and pyrimidine biosynthesis. Punicalagin treatment also induced an SOS cellular response to damaged DNA. Transcriptional comparison of marker genes shows that the punicalagin‐induced iron starvation and SOS responses resembles those produced by EDTA and ciprofloxacin. These results show that punicalagin adversely alters bacterial growth by disrupting iron homeostasis and that it induces SOS, possibly through DNA biosynthesis inhibition.
Alkyl‐mannoside derivatives: Glycolipids able to form big size aggregates
Authors: Sandoval‐Altamirano C. , Sanchez S.A. , Pizarro N. , Morales J. , Gunther G.
Published: March 2018

Three different series of alkyl mannoside derivatives have been synthesized, designing the hydrophobic portion to provide different topology to the surfactant and, hence, modulating their aggregation properties. The aggregates formed were characterized using both physical and photophysical methodologies, such as surface tension, dynamic light scattering, and emission of selected fluorescent probes. The non‐ionic sugar surfactants have been widely used in studies of membrane solubilization and protein purification. Indeed, mannoside unit, nonionic and hydrophilic, can be selectively recognized by several lectins, which are proteins present in different membranes. Then, the specific interactions of these derivatives incorporated into synthetic bilayers with lectins have been studied and reported. In this work, monoalkyl derivatives with a presumably conical shape and dialkyl derivatives with cylindrical ones, including also a third family with a hydrophilic spacer were studied. These compounds are able to self‐aggregate to form micelle like structures or bilayers despite their topology. Additionally, they are able to form bilayers, using cosurfactants like cholesterol.
Diketopyrrolopyrrole‐based polymer nanowires: Control of chain conformation and nucleation
Authors: Cao Xinxiu , Chen Liang , Zhao Kefeng , Liu Jiangang , Han Yanchun
Published: March 2018

Understanding the nucleation process is very important in growing polymer nanowires as it plays a decisive role in determining the crystal structure and size distribution. Polymer chain conformation determines whether the polymer chains could assemble to nuclei or not. Here, chain conformation and the nucleation process were controlled to grow 3,6‐bis‐(thiophen‐2‐yl)‐N,N′‐bis(2‐decyl‐1‐tetradecyl)‐1,4‐dioxo‐pyrrolo[3,4‐c]pyrrole and thieno[3,2‐b]thiophene (DT‐PDBT‐TT) nanowires. We changed the conformation of DT‐PDBT‐TT in solution and controlled the nucleation process by using a main solvent:cosolvent system. The main solvent was a low boiling point good solvent, and the cosolvent was consisted of two high boiling point solvents with different solubility. In fact, the chain conformation in the pristine solution was changed by choosing different main solvents (with H‐bond, π–π or none interaction with the main chain) and temperatures. The absorption spectrum and TEM images showed that trichloro ethylene (TCE) was the best main solvent because it has H‐bond interaction with the polymer main chain and DT‐PDBT‐TT conformation in it approaching unimer coil conformation, which is beneficial to grow nanowires. Mixed o‐dichlorobenzene (ODCB) and anisole (AS) with different ratios were used to changing the solubility step by step to control nucleation process. Only when marginal cosolvent (ODCB:AS = 1:1) was added, could it decrease the nuclei number and avoided the aggregates simultaneously. As the main solvent evaporated slowly, the nucleation and growth happened, leading to the nanowires formation. The resulting nanowires were about 63 nm in width and one to two microns in length. The width of the DT‐PDBT‐TT structures suggests that the polymer chains are oriented along the fibril axis. Our results indicated that there are two requirements for the nanowire formation, (1) the polymer chain conformation should approach unimer coil; (2) the nucleation density should be optimized, not too much and no aggregation happened. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 833–841
Difficult conversations: Discussing prognosis with children with cystic fibrosis
Authors: Farber Julia Gray , Prieur Mary G. , Roach Christine , Shay Rosemary , Walter Michelle , Borowitz Drucy , Dellon Elisabeth P.
Published: March 2018

Background Despite the chronic, progressive, and life‐threatening nature of cystic fibrosis (CF), there are no guidelines for when and how to communicate prognosis to children with CF.

Methods

Semi‐structured interviews with young adults with CF, parents of young adults with CF, and multidisciplinary CF health care providers assessed recall of and practices for communicating about prognosis. Recommendations for improvements were also solicited.

Results

Young adults with CF recalled learning that life expectancy is limited by CF between the ages of 8 and 16 years, and that CF is a progressive disease between the ages of 7 and 19 years. They reported that the information often came from CF physicians or from online resources. Patients and parents reported earlier knowledge of prognosis than providers assumed. While learning about prognosis caused sadness and stress for some patients and families, others denied negative feelings. Interestingly, most patients reported that disclosure of prognosis had minimal impact on their adherence and treatment goals. Patients and parents reported wanting physicians to be involved in conversations about prognosis. However, providers noted several barriers to discussing prognosis, including their own reluctance, time limitations, and uncertainty about appropriate timing and content of communication.

Conclusions

Communication about prognosis is important but also difficult for providers, patients, and families. Appropriately timed conversations, using tools to facilitate communication, could ensure patients receive timely, accurate information.
Identification of an IL‐1‐induced gene expression pattern in AR+ PCa cells that mimics the molecular phenotype of AR− PCa cells
Authors: Thomas‐Jardin Shayna E. , Kanchwala Mohammed S. , Jacob Joan , Merchant Sana , Meade Rachel K. , Gahnim Nagham M. , Nawas Afshan F. , Xing Chao , Delk Nikki A.
Published: March 2018

Background

In immunosurveillance, bone‐derived immune cells infiltrate the tumor and secrete inflammatory cytokines to destroy cancer cells. However, cancer cells have evolved mechanisms to usurp inflammatory cytokines to promote tumor progression. In particular, the inflammatory cytokine, interleukin‐1 (IL‐1), is elevated in prostate cancer (PCa) patient tissue and serum, and promotes PCa bone metastasis. IL‐1 also represses androgen receptor (AR) accumulation and activity in PCa cells, yet the cells remain viable and tumorigenic; suggesting that IL‐1 may also contribute to AR‐targeted therapy resistance. Furthermore, IL‐1 and AR protein levels negatively correlate in PCa tumor cells. Taken together, we hypothesize that IL‐1 reprograms AR positive (AR+) PCa cells into AR negative (AR−) PCa cells that co‐opt IL‐1 signaling to ensure AR‐independent survival and tumor progression in the inflammatory tumor microenvironment.

Methods

LNCaP and PC3 PCa cells were treated with IL‐1β or HS‐5 bone marrow stromal cell (BMSC) conditioned medium and analyzed by RNA sequencing and RT‐QPCR. To verify genes identified by RNA sequencing, LNCaP, MDA‐PCa‐2b, PC3, and DU145 PCa cell lines were treated with the IL‐1 family members, IL‐1α or IL‐1β, or exposed to HS‐5 BMSC in the presence or absence of Interleukin‐1 Receptor Antagonist (IL‐1RA). Treated cells were analyzed by western blot and/or RT‐QPCR.

Results

Comparative analysis of sequencing data from the AR+ LNCaP PCa cell line versus the AR− PC3 PCa cell line reveals an IL‐1‐conferred gene suite in LNCaP cells that is constitutive in PC3 cells. Bioinformatics analysis of the IL‐1 regulated gene suite revealed that inflammatory and immune response pathways are primarily elicited; likely facilitating PCa cell survival and tumorigenicity in an inflammatory tumor microenvironment.

Conclusions

Our data supports that IL‐1 reprograms AR+ PCa cells to mimic AR− PCa gene expression patterns that favor AR‐targeted treatment resistance and cell survival.
Comparison of demographic fitness and biocontrol effectiveness of two parasitoids, Encarsia sophia and Eretmocerus hayati (Hymenoptera: Aphelinidae), against Bemisia tabaci (Hemiptera: Aleyrodidae)
Authors: Xu Hai‐Yun , Yang Nian‐Wan , Chi Hsin , Ren Guo‐Dong , Wan Fang‐Hao
Published: March 2018

BACKGROUND

The autoparasitoid Encarsia sophia and the primary parasitoid Eretmocerus hayati are two important parasitoids used against the whitefly Bemisia tabaci, with different reproductive strategies. To incorporate these two parasitoids into a sustainable whitefly control program, it is necessary to evaluate and compare their fitness and biocontrol effectiveness under identical experimental conditions. The demographic characteristics, parasitism rate and host‐feeding rate of En. sophia and Er. hayati were analyzed using an age‐stage, two‐sex life table and the CONSUME‐MSChart computer program.

RESULTS

The mean fecundity of Er. hayati (211.4 offspring per female) was significantly higher than that of En. sophia (101.6 offspring per female), although the oviposition days of En. sophia was longer than that of Er. hayati. No significant difference was found in the intrinsic rate of increase (r), finite rate of increase (λ) or net reproduction rate (R0) between the two parasitoid species, but the mean generation time (T) of En. sophia (18.8 days) was significantly shorter than that of Er. hayati (20.5 days). The net host feeding rate (C0) of En. sophia was 84.1 whiteflies per individual, significantly higher than the 17.6 whiteflies per individual consumed by Er. hayati. The finite killing rate (ν) of En. sophia (0.6713) for whitefly was significantly greater than that produced by Er. hayati (0.3652).

CONCLUSION

The En. sophia population can increase faster and have a higher killing potential than the Er. hayati population. Taking both the demographic fitness and killing potential of the two parasitoids into consideration, En. sophia would be the preferred choice to release in a biological control program. © 2018 Society of Chemical Industry
Enhanced NO2 Sensing Property of ZnO by Ga Doping and H2 Activation
Authors: Wang Zhou , Xie Zheng , Bian Luozhen , Li Wenhui , Zhou Xinyuan , Wu Xiaofeng , Yang Zaixing , Han Ning , Zhang Jie , Chen Yunfa
Published: March 2018

Ga‐doped ZnO nanoparticles are successfully prepared by a facile coprecipitation method and then are activated by H2 annealing. The as‐prepared ZnO powders are characterized by X‐ray diffractometer (XRD), Brunauer–Emmett–Teller (BET), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy, Raman and photoluminescence spectroscopies. Gas sensing property using NO2 as probe shows that the 1 at.% Ga‐ZnO powders activated in H2 at 540 °C showed high NO2 response of ≈50/ppm, high selectivity toward typical interferences such as ethanol, acetone, toluene, NO, SO2, C2H6, and C2H4 and high stability as measured at 200 °C. On the contrary, the pure ZnO and the Ga‐ZnO without H2 activation show far lower response, which illustrates the effect of Ga dopant activation by H2 annealing aimed for the high performance gas sensing materials.
Growth of High‐Quality AlN and AlGaN Films on Sputtered AlN/Sapphire Templates via High‐Temperature Annealing
Authors: Hakamata Junya , Kawase Yuta , Dong Lin , Iwayama Sho , Iwaya Motoaki , Takeuchi Tetsuya , Kamiyama Satoshi , Miyake Hideto , Akasaki Isamu
Published: March 2018

We investigated the fabrication and characterization of AlN and AlGaN epilayers grown on sputtered and annealed AlN/sapphire templates by metal organic vapor phase epitaxy. The surfaces of the AlN homoepilayers exhibited clear step‐terrace structures with minimal root mean square roughness values. X‐ray rocking curve (XRC) measurements showed that the AlN homoepilayers had smaller (102)‐plane full width at half maximum (FWHM) values (192 arcsec) than the AlN/sapphire templates did (214 arcsec), and that they had larger (0002)‐plane FWHM values (97 arcsec) than the AlN/sapphire templates (22 arcsec). The latter results may be due to the wafer curvature increasing as the AlN layer thickness increases. We also present results for the growth of AlGaN heteroepilayers with different AlN compositions on AlN/sapphire templates that either did or did not contain AlN regrowth layers. High‐AlN mole fraction AlGaN heteroepilayers had larger (0002)‐plane FWHM values and smaller (102)‐plane FWHM values than low‐AlN mole fraction AlGaN. Furthermore, the presence of an AlN regrowth layer tended to have a negative effect on the high‐AlN mole fraction AlGaN layers. The above results are discussed using lattice mismatch, wafer curvature, surface condition, and growth temperature parameters.
Ambient levels of PFOS and PFOA in multiple environmental media
Authors: Vedagiri Usha K. , Anderson Richard H. , Loso Heather M. , Schwach Catherine M.
Published: March 2018

Making remediation and risk management decisions for widely‐distributed chemicals is a challenging aspect of contaminated site management. The objective of this study is to present an initial evaluation of the ubiquitous, ambient environmental distribution of poly‐ and perfluoroalkyl substances (PFAS) within the context of environmental decision‐making at contaminated sites. PFAS are anthropogenic contaminants of emerging concern with a wide variety of consumer and industrial sources and uses that result in multiple exposure routes for humans. The combination of widespread prevalence and low screening levels introduces considerable uncertainty and potential costs in the environmental management of PFAS.

PFAS are not naturally‐occurring, but are frequently detected in environmental media independent of site‐specific (i.e., point source) contamination. Information was collected on background and ambient levels of two predominant PFAS, perfluorooctane sulfonate and perfluorooctanoate, in North America in both abiotic media (soil, sediment, surface water, and public drinking water supplies) and selected biotic media (human tissues, fish, and shellfish). The background or ambient information was compiled from multiple published sources, organized by medium and concentration ranges, and evaluated for geographical trends and, when available, also compared to health‐based screening levels. Data coverage and quality varied from wide‐ranging and well‐documented for soil, surface water, and serum data to more localized and less well‐documented for sediment and fish and shellfish tissues and some uncertainties in the data were noted. Widespread ambient soil and sediment concentrations were noted but were well below human health‐protective thresholds for direct contact exposures. Surface water, drinking water supply waters (representing a combination of groundwater and surface water), fish and shellfish tissue, and human serum levels ranged from less than to greater than available health‐based threshold values. This evaluation highlights the need for incorporating literature‐based or site‐specific background into PFAS site evaluation and decision‐making, so that source identification, risk management, and remediation goals are properly focused and to also inform general policy development for PFAS management.
Ultrathin TiO2 Coating on LiCoO2 for Improved Electrochemical Performance as Li–Ion Battery Cathode
Authors: Jayasree Silpasree S. , Nair Shantikumar , Santhanagopalan Dhamodaran
Published: March 2018

Surface modification of LiCoO2 (LCO) gained much attention as it could play a prominent role in improving electrochemical performance and structural stability. Herein, we report an ultra‐thin TiO2 coating on LiCoO2 (LCO‐TiO2) as a potential candidate to overcome the electrochemical, structural instability and interface issues of the bare‐LCO. The structural properties as well as electrochemical performances of bare‐LCO and LCO‐TiO2 were investigated by X‐Ray diffraction, Transmission Electron Microscopy (TEM), X‐ray Photoelectron Spectroscopy (XPS), Galvanostatic charge‐discharge and electrochemical impedance spectroscopy (EIS). At the end of 100 cycles, 1C rate capacity retention was about 50% and 90% for bare‐LCO and LCO‐TiO2 respectively. Rate studies showed that the bare LCO exhibited a specific capacity of ∼120 mAh/g and only 16 mAh/g at 1C and 60 discharge rates respectively whereas, the TiO2 coated LCO showed a capacity of ∼132 mAh/g and nearly 98 mAh/g at 1C and 60C discharge rates respectively. The implementation of TiO2 coating over LiCoO2 enhanced the electrochemical performance, cell stability as well as efficiency.
Constructing Multifunctional Heterostructure of Fe2O3@Ni3Se4 Nanotubes
Authors: Zheng Penglun , Zhang Yu , Dai Zhengfei , Zheng Yun , Dinh Khang Ngoc , Yang Jun , Dangol Raksha , Liu Xiaobo , Yan Qingyu
Published: March 2018

Heterostructures have attracted increasing attention due to their amazing synergetic effects, which may improve the electrochemical properties, such as good electrical/ionic conductivity, electrochemical activity, and mechanical stability. Herein, novel hierarchical Fe2O3@Ni3Se4 nanotubes are successfully fabricated by a multistep strategy. The nanotubes show length sizes of ≈250–500 nm, diameter sizes of ≈100–150 nm, and wall thicknesses of ≈10 nm. The as‐prepared Fe2O3@Ni3Se4 nanotubes with INi:Fe = 1:10 show excellent Li storage properties (897 mAh g−1 high reversible charge capacity at 0.1 A g−1), good rate performance (440 mAh g−1 at 5 A g−1), and outstanding long‐term cycling performance (440 mAh g−1 at 5 A g−1 during the 300th cycle) as an anode material for lithium ion batteries. In addition, the Fe2O3@Ni3Se4 nanotubes with INi:Fe = 1:10 (the atomic ratio between Ni and Fe) show superior electrocatalytic performance toward the oxygen evolution reaction with an overpotential of only 246 mV at 10 mA cm−2 and a low Tafel slope of 51 mV dec−1 in 1 m KOH solution.
Comparative Study on the Microstructure Characteristics and Enhanced Mechanical Properties of Spray Formed GCr15 Bearing Steel
Authors: Liu Mingxiang , Cui Zhenshan , Shang Xiaoqing , Zhou Shan
Published: March 2018

Bearing steel GCr15 is prepared by spray forming, and then goes through hot forging and heat treatment. Compared with conventionally cast material, microstructure characteristics and transformation mechanism of spray formed GCr15 bearing steel during each process are analyzed, and the final mechanical properties including strength, elongation, impact toughness, and wear resistance are tested. The results show that the microstructure of as‐sprayed GCr15 bearing steel is homogeneous with very fine pearlite which is formed under large undercooling. After hot forging, the microstructure still exhibits high homogeneity without any coarse carbides. Fine martensite and uniform carbide distribution are observed in the microstructure after heat treatment; moreover, the volume fraction of the retained austenite is higher than that of the conventional GCr15 steel due to the increased carbon concentration in prior austenite matrix. With the optimized microstructure, the overall mechanical performances of spray formed GCr15 bearing steel have been significantly improved, which indicates a great potential of spray forming in developing high‐quality bearing steels.