bluuebunny/crossref_metadata_2025 huggingface dataset:
Boosting heterologous protein production yield by adjusting global nitrogen and carbon metabolic regulatory networks inBacillus subtilis
Authors: Cao Haojie , Villatoro-Hernandez Julio , Weme Ruud Detert Oude , Frenzel Elrike , Kuipers Oscar P.
Published: May 2018

Bacillus subtilisis extensively applied as a microorganism for the high-level production of heterologous proteins. Traditional strategies for increasing the productivity of this microbial cell factory generally focused on the targeted modification of rate-limiting components or steps. However, the longstanding problems of limited productivity of the expression host, metabolic burden and non-optimal nutrient intake, have not yet been solved to achieve production strain improvements. To tackle this problem, we systematically rewired the regulatory networks of the global nitrogen and carbon metabolism by random mutagenesis of the pleiotropic transcriptional regulators CodY and CcpA, to allow for optimal nutrient intake, translating into significantly higher heterologous protein production yields. Using a β-galactosidase expression and screening system and consecutive rounds of mutagenesis, we identified mutant variants of both CcpA and CodY that in conjunction increased production levels up to 290%. RNA-Seq and electrophoretic gel mobility shift analyses showed that amino acid substitutions within the DNA-binding domains altered the overall binding specificity and regulatory activity of the two transcription factors. Consequently, fine-tuning of the central metabolic pathways allowed for enhanced protein production levels. The improved cell factory capacity was further demonstrated by the successfully increased overexpression of GFP, xylanase and a peptidase in the double mutant strain.

Highlights

The global transcription machinery engineering (gTME) technique was applied to build mutational libraries of the pleiotropic regulators CodY and CcpA inBacillus subtilis

Specific point mutations within the DNA-binding domains of CodY and CcpA elicited alterations of the binding specificity and regulatory activity

Changes in the transcriptome evoked the reprogramming of networks that gear the carbon and nitrogen metabolism

The rewired metabolic networks provided a higher building block capacity for heterologous protein production by adjusting the nutrient uptake and channeling its utilization for protein overexpression
Single-cell transcriptome profiling of theCionalarval brain
Authors: Sharma Sarthak , Wang Wei , Stolfi Alberto
Published: May 2018

The tadpole-type larva ofCionahas emerged as an intriguing model system for the study of neurodevelopment. TheCiona intestinalisconnectome has been recently mapped, revealing the smallest central nervous system (CNS) known in any chordate, with only 177 neurons. This minimal CNS is highly reminiscent of larger CNS of vertebrates, sharing many conserved developmental processes, anatomical compartments, neuron subtypes, and even specific neural circuits. Thus, theCionatadpole offers a unique opportunity to understand the development and wiring of a chordate CNS at single-cell resolution. Here we report the use of single-cell RNAseq to profile the transcriptomes of single cells isolated by fluorescence-activated cell sorting (FACS) from the whole brain ofCiona robusta(formerlyintestinalis Type A)larvae. We have also compared these profiles to bulk RNAseq data from specific subsets of brain cells isolated by FACS using cell type-specific reporter plasmid expression. Taken together, these datasets have begun to reveal the compartment- and cell-specific gene expression patterns that define the organization of theCionalarval brain.
Simulating Contact Using the Elastic Foundation Algorithm in OpenSim
Authors: Hast Michael W. , Hanson Brett G. , Baxter Josh R.
Published: May 2018

Modeling joint contact is necessary to test many questions using simulation paradigms, but this portion of OpenSim is not well understood. The purpose of this study was to provide a guide for implementing a validated elastic foundation contact model in OpenSim. First, the load-displacement properties of a stainless steel ball bearing and ultra high molecular weight polyethylene (UHMWPE) slab were recorded during a controlled physical experiment. These geometries were imported and into OpenSim and contact mechanics were modeled with the on-board elastic foundation algorithm. Particle swarm optimization was performed to determine the elastic foundation model stiffness (2.14×1011 ± 6.81×109 N/m) and dissipation constants (0.999 ± 0.003). Estimations of contact forces compared favorably with blinded experimental data (root mean square error: 87.58 ± 1.57 N). Last, total knee replacement geometry was used to perform a sensitivity analysis of material stiffness and mesh density with regard to penetration depth and computational time. These simulations demonstrated that material stiffnesses between 1011 and 1012 N/m resulted in realistic penetrations (< 0.15mm) when subjected to 981N loads. Material stiffnesses between 1013 and 1015 N/m increased computation time by factors of 12–23. This study shows the utility of performing a simple physical experiment to tune model parameters when physical components of orthopaedic implants are not available to the researcher. It also demonstrates the efficacy of employing the on-board elastic foundation algorithm to create realistic simulations of contact between orthopaedic implants.
Extensile motor activity drives coherent motions in a model of interphase chromatin
Authors: Saintillan David , Shelley Michael J. , Zidovska Alexandra
Published: May 2018

The 3D spatiotemporal organization of the human genome inside the cell nucleus remains a major open question in cellular biology. In the time between two cell divisions, chromatin – the functional form of DNA in cells – fills the nucleus in its uncondensed polymeric form. Recent in-vivo imaging experiments reveal that the chromatin moves coherently, having displacements with long-ranged correlations on the scale of microns and lasting for seconds. To elucidate the mechanism(s) behind these motions, we develop a novel coarse-grained active-polymer model where chromatin is represented as a confined flexible chain acted upon by molecular motors, which perform work by exerting dipolar forces on the system. Numerical simulations of this model account for steric and hydrodynamic interactions as well as internal chain mechanics. These demonstrate that coherent motions emerge in systems involving extensile dipoles and are accompanied by large-scale chain reconfigurations and nematic ordering. Comparisons with experiments show good qualitative agreement and support the hypothesis that self-organizing long-ranged hydrodynamic couplings between chromatin-associated active motor proteins are responsible for the observed coherent dynamics.
Ethyl 2-[(2E)-4-decyl-3-oxo-1,2,3,4-tetrahydroquinoxalin-2-ylidene]acetate
Authors: Abad Nadeem , El Bakri Youness , Ramli Youssef , Essassi El Mokhtar , Mague Joel T.
Published: May 2018

In the title compound, C22H32N2O3, the tetrahydroquinoxaline unit is planar. The ester substituent is nearly coplanar with this ring system as a result of an intramolecular N—H...O hydrogen bond. In the crystal, C—H...O hydrogen bonds and π-stacking interactions form oblique stacks which are connected into pairs by additional C—H...O hydrogen bonds. These pairs are further linked into thick sheets, with the n-decyl chains extending out from both surfaces as a result of a third set of C—H...O hydrogen bonds. Intercalation of the n-decyl chains completes the crystal packing.
Robot learning human stiffness regulation for hybrid manufacture
Authors: Zeng Chao , Yang Chenguang , Chen Zhaopeng , Dai Shi-Lu
Published: May 2018

Purpose

Teaching by demonstration (TbD) is a promising way for robot learning skills in human and robot collaborative hybrid manufacturing lines. Traditionally, TbD systems have only concentrated on how to enable robots to learn movement skills from humans. This paper aims to develop an extended TbD system which can also enable learning stiffness regulation strategies from humans.

Design/methodology/approach

Here, the authors propose an extended dynamical motor primitives (DMP) framework to achieve this goal. In addition to the advantages of the traditional ones, the authors’ framework can enable robots to simultaneously learn stiffness and the movement from human demonstrations. Additionally, Gaussian mixture model (GMM) is used to capture the features of movement and of stiffness from multiple demonstrations of the same skill. Human limb surface electromyography (sEMG) signals are estimated to obtain the reference stiffness profiles.

Findings

The authors have experimentally demonstrated the effectiveness of the proposed framework. It shows that the authors approach could allow the robot to execute tasks in a variable impedance control mode with the learned movement trajectories and stiffness profiles.

Originality/value

In robot skill acquisition, DMP is widely used to encode robotic behaviors. So far, however, these DMP modes do not provide the ability to properly represent and generalize stiffness profiles. The authors argue that both movement trajectories and stiffness profiles should be considered equally in robot skill learning. The authors’ approach has great potential of applications in the future hybrid manufacturing lines.
Talent turnover and retention research
Authors: Alferaih Adel , Sarwar Shagufta , Eid Ayman
Published: May 2018

Purpose

The purpose of this paper is to understand the direct impact of some of the salient factors from the talent management (TM) literature (role conflict, extrinsic rewards, and job satisfaction) and the indirect impact of other factors (organisational commitment, talent retention, and talent engagement) on talent turnover intention.

Design/methodology/approach

A survey questionnaire collected 521 valid responses from employees holding managerial and non-managerial positions at various levels in 54 five-star hotels in 6 cities in Saudi Arabia.

Findings

Significant support was found for all nine hypotheses formulated to test the relationships among the seven constructs above. The model was found to explain 68 per cent of variance in talent turnover intention.

Research limitations/implications

The study contributes to human resource management literature in general and TM in particular by examining the different constructs used in the TM models and by conceptualising a research model, which was empirically validated within the service sector in the context of Saudi Arabia.

Practical implications

The research has several implications for practitioners in the tourism/service sector in the Middle East, pertaining to the management of talented employees. Specifically, it recommends that managers should promote training and development scenarios and provide a better work environment to strengthen individuals’ commitment to their jobs.

Originality/value

This is one of the first studies to examine a comprehensive model of TM in the Arab world in general and in Saudi Arabia in particular, using data gathered from employees in the tourism sector.
Incentive pay configurations: the influence of national culture
Authors: Prince Nicholas R. , Prince J. Bruce , Kabst Rüediger
Published: May 2018

Purpose

The purpose of this paper is to investigate the influence of national culture on the adoption of four different incentive pay bundles (incentive maximizer, contingent rewarder, profit rewarder, and incentive minimizer) using GLOBE national culture dimensions in 14 countries. It uses incentive pay bundles derived by Princeet al.(2016).

Design/methodology/approach

The study adopted multilevel random-intercept logistic modeling using firm incentive practice usage from the CRANET database and country culture scores from the GLOBE study.

Findings

Evidence suggests that in-group collectivism is associated with increased use of the incentive maximizer approach, in which firms use a combination of high levels of individual, team, and profit sharing incentives, and decreased use of the incentive minimizer approach (where firms minimally employ incentives) and the individual and team bonus focused contingent rewarder configuration. Higher uncertainty avoidance is linked to increased use of the profit rewarder approach (where only profit sharing is emphasized) and decreased use of the contingent rewarder approach. Performance-orientation cultures appear to support using the incentive maximizer and avoiding the incentive minimizer bundles.

Originality/value

This study investigates incentive practice bundles that firms use verses separate analysis of practices and use the GLOBE culture metrics. It utilizes multilevel modeling, which has been lacking in past studies of culture and incentives.
The role of family in the township informal economy of food and drink in KwaMashu, South Africa
Authors: Petersen Leif , Charman Andrew
Published: May 2018

Purpose

The purpose of this paper is to provide a qualitative investigation of family employment dynamics in the KwaMashu township economy.

Design/methodology/approach

Using a small area census research method, the researchers identified 1,556 businesses located in a settlement of 2 km2. Of these enterprises, 694 (45 percent) traded in fast moving consumer goods, notably food and/or drink. The main retailers were small shops (spaza shops) and liquor outlets (bars or shebeens), greengrocers, sellers of meat and poultry products, house shops, restaurants, takeaways and tuckshops. Firm surveys were conducted with 270 businesses in four predominant sectors: liquor retail, grocery retail, early childhood educators and hair care businesses.

Findings

The research found that 40 percent of the surveyed firms in these sectors employ family members on a full-time basis, whereas merely 26 percent of firms employ family members on a part-time basis. In the grocery retail sector, about half of family employees are remunerated on a wage basis, the other half are paid in-kind (40 paper of the total) or on a profit share arrangement. In liquor retail and educare sectors, the majority of family members are paid wages. Female-run enterprises employ less family members on a full-time basis (except in the grocery sector), yet employ more family members on a part-time basis with a higher portion of wages paid in-kind.

Research limitations/implications

Family plays an important role in township enterprises. Beyond direct employment, township enterprises fulfill an important social protection and neighborhood relationship function for business operators and their families. The familial relationship to micro-enterprises should be seen through the lens of bricolage (Gras and Nason, 2015).

Originality/value

In this respect, the authors confirm three benefits of family firms: the creation of social protection though family beneficiation, the provision of employment and work experience and the strategic use of family resources.
Effects of gender quotas in Italy: a first impact assessment in the Italian banking sector
Authors: De Vita Luisa , Magliocco Antonella
Published: May 2018

Purpose

The purpose of this paper is to provide a first impact assessment of the Italian quota law in order to explore whether “gender equality by law” contributes to redefining, albeit in part, consolidating and establishing positions of power and decision making. The paper analyses these dynamics by focusing on a specific economic sector, the banking sector. The analysis strives to determine: whether binding quotas are giving rise to an apparent enforcement by building up new distortionary equilibria (such as new forms of horizontal segregation); what extent the financial crisis has impacted on the rhetoric of female representation, and whether it has pushed towards a “regenerative” organizational change aimed at achieving a more inclusive and egalitarian image.

Design/methodology/approach

The paper is organized as follows. Section 2 reviews the theoretical and empirical debate on gender diversity and quota impact. Section 3 reports macro and micro data on the italian system; Section 4 describes the Italian banking system and gives a first impact assessment on Italian banks of the mandatory gender quotas in Italy (the so-called “Golfo-Mosca law,” named after MPs who proposed the law); some qualitative considerations are carried out on the reactions of Italian banks to the financial crisis in terms of “bridge policies” aimed at corresponding to a higher demand of customer satisfaction and fairness. Section 5 concludes and summarizes the finding of the study.

Findings

The Italian banking system is not so dramatically ranked among the EU countries as in the recent past. The gender rebalance in management bodies could be considered rather satisfying. If we compare ten-year-old findings, the number of women on board of directors has tripled. But data clearly show a dichotomy due to significant differences between listed and non-listed banks. In non-listed banks, women are still relegated to an under-represented position, reaching only 13 percent on boards of directors (as against 33 percent in listed banks). The data confirm the results found in non-financial sector that women are significantly better represented on audit boards. In accordance with all previous studies, no relevant changes can be noticed on key-decision roles: no CEOs or Directors general are women in listed banks, and women are always more represented in non-executive functions.

Originality/value

The paper analyses the law experience in Italy as a significant case study by proving that rules such as temporary binding gender quotas (introduced by law in 2011) can be useful, but not always enough to remove blocking or distortive factors in organizational ladders.
Whose home is it anyway? Performing multiple selves while doing organizational ethnography
Authors: Cnossen Boukje
Published: May 2018

Purpose

The purpose of this paper is to nuance the idea of natural access proposed by Mats Alvesson in his description of at-home ethnography, and to offer a performative view of Alvesson’s suggestion that, in at-home ethnography, the ethnographer must work with “the processual nature of the researcher’s self.”

Design/methodology/approach

The author offers a reflection on the several years of ethnographic research the author conducted, of which some parts were done in a living community of which the author was part. Being literally at home, as well as being very familiar in the other research settings the author describes, allows for a critical reflection on what “at-homeness” means.

Findings

Using Butler’s notion of performativity, the author argues that “the processual nature of the researcher’s self” Alvesson speaks of, can best be understood as multiple selves, of which some emerge during the research process. The author furthermore problematizes Alvesson’s use of the term “natural access,” by arguing that this kind of access is neither easy, nor devoid of power relations.

Originality/value

This paper uses an experience of conducting research in the home, as well as an experience conducting research in a setting where the researcher arguably blent in well, to question what the “at-home” in at-home ethnography means, and how the researcher can deal with it.
Assessing the effects of multichannel service provider corporate reputation on customer new product adoption and RFM value
Authors: Walsh Gianfranco , Schaarschmidt Mario , Ivens Stefan
Published: May 2018

Purpose

Service providers leverage their corporate reputation management efforts to increase revenues by shaping customer attitudes and behaviours, yet the effects on customer innovation adoption and customer value remain unclear. In an extended conceptualisation of customer-based corporate reputation (CBR), the purpose of this paper is to propose that customer perceived risk, perceived value, and service separation are contingencies of the relationship between CBR and two key customer outcomes: customer new product adoption proneness (CPA) and recency-frequency-monetary (RFM) value.

Design/methodology/approach

Using a predictive survey approach, 1,001 service customers assess the online or offline operations of six multichannel retailers. The hypothesised model is tested using structural equation modelling and multigroup analysis.

Findings

The analysis reveals significant linkages of CBR with perceived risk and perceived value, as well as between perceived risk and perceived value and from perceived value to CPA and RFM value. These linkages vary in strength across unseparated (offline) and separated (online) services.

Research limitations/implications

This study uses cross-sectional data to contribute to literature that relates CBR to relevant customer outcomes by considering CPA and RFM value and investigating contingent factors. It provides conceptual and empirical evidence that price appropriateness represents a new CBR dimension.

Practical implications

The results reveal that CBR reduces customers’ perceived risk and positively affects their perceived value, which drives CPA and RFM value. Multichannel retailers can create rewarding customer relationships by building and nurturing good reputations.

Originality/value

This study is the first to link CBR with customer product adoption proneness and value, two important customer measures. It proposes and tests an extended conceptualisation of CBR.
Determinants of cluster leadership and identification on cluster innovation model
Authors: Chen Chun-Liang , Lin Yao-Chin , Chen Wei-Hung , Heng Xin-Si
Published: May 2018

Purpose

The purpose of this paper is to prove the importance of both cluster leadership and identification on cluster innovation.

Design/methodology/approach

The case studies presented in this study involve a cluster by micro-enterprises in Yilan, Taiwan. Data collected during interviews, observations and secondary data provide understanding and practices for the impact of cluster identification on cluster innovation.

Findings

This study proved: first, the importance of cluster identification on innovation by representing the need of consensus and collaboration of the members in conducting innovation actions; and second, the cluster identification is influenced by the cluster leadership by showing high satisfaction of the leader, close interaction between the members and high identification with the cluster.

Research limitations/implications

This study predicts the ongoing cluster innovation activities will be achieved due to the transformational leadership and high cluster identification.

Originality/value

This study enriches the factors of cluster innovation accomplishment and proposes the important of cluster identification, which has not been discussed much in the past.
Foreign firms’ strategic positioning and performance in a host market
Authors: Xie Henry Yu , Xie Qian (Jane) , Zhao Hongxin
Published: May 2018

Purpose

Strategic positioning of foreign firms in a host market is vital for their success. By integrating the resource partitioning theory and the resource-based view, this study aims to investigate foreign firms’ strategic positioning (i.e. their choice of generalist or specialist positioning strategy) and its performance implications in the US market.

Design/methodology/approach

The final sample includes 212 foreign companies from 28 countries operating in the US market. Multiple data sources were used to collect data of these foreign companies’ subsidiaries in the USA This study used logistic regression to test its major hypotheses.

Findings

The results of this study suggest that a generalist positioning strategy is positively related to performance in a host market. It is also found that market concentration and local market knowledge moderate this strategic positioning – performance relationship.

Research limitations/implications

For a foreign firm that enters a host market, market concentration (an industry-level factor) in the host market and the firm’s local market knowledge (a firm-specific factor) play prominent roles in the strategic positioning – performance relationship.

Originality/value

This study offers a novel perspective of international business strategy by applying the lens of resource partitioning theory to study the relationships between multinational enterprises’ strategic positioning and performance. This study contributes to the strategy literature in that it examines the performance implications of firms’ strategic positioning (i.e. generalist or specialist positioning).
Building brand and fan relationships through social media
Authors: Thompson Ashleigh-Jane , Martin Andrew J. , Gee Sarah , Geurin Andrea N.
Published: May 2018

Purpose

As the popularity of social media increases, sports brands must develop specific strategies to use them to enhance fan loyalty and build brand equity. The purpose of this paper is to explore how two social media platforms were utilised by the Grand Slam tennis events to achieve branding and relationship marketing goals.

Design/methodology/approach

A content analytic design was employed to examine Twitter and Facebook posts from the official accounts during, and post-, each respective event.

Findings

Both sites were utilised to cultivate long-term relationships with fans and develop brand loyalty, rather than to undertake short-term marketing activations. However, these sites appear to serve a different purpose, and therefore unique strategies are required to leverage opportunities afforded by each. Interestingly, brand associations were utilised more frequently during the post-event time period.

Practical implications

This study offers practitioners with useful insight on branding and relationship-building strategies across two social platforms. These results suggest that strategies appear dependent on the event, timeframe and specific platform. Moreover, the events’ differences in post use and focus may also indicate some differences related to event branding in an international context. Furthermore, sport organisations should look to leverage creative strategies to overcome limitations that platform-specific functionality may impose.

Originality/value

This study offers unique insights brand-building efforts in an international event setting, which differ in a range of contextual factors that impact on social media utilisation.
Suffering in receivers: Negative effects of noise persist regardless of experience in female anurans
Authors: Senzaki Masayuki , Kadoya Taku , Francis Clinton D. , Ishiyama Nobuo , Nakamura Futoshi
Published: May 2018

Anthropogenic noise is widespread, and growing evidence suggests that it can negatively affect animals through many different mechanisms including masking of cues and signals, distraction, and aversion to noise.

Acoustic masking has received the most attention from researchers and recent evidence suggests that masking effects can be mitigated by alteration of signal frequencies or amplitudes by signalers. Additionally, alteration can be a learned response via prior experience with noise exposure. However, it remains unclear whether distraction or aversive effects due to noise can be mitigated by prior experience with noise, especially among signal receivers.

Here, we addressed this gap by separating mechanisms of noise disturbances on female phonotaxis towards male advertisement calls in anurans. To do this, we experimentally examined phonotaxis of gravid females that differ in their prior experience with noise under three acoustic manipulations: spectrally overlapping and non‐overlapping noise that either mask or do not mask male advertisement calls respectively, plus a silent control.

We confirm two experience‐dependent responses of noisy‐site individuals relative to quiet‐site individuals: faster initiation of phonotaxis under non‐overlapping noise and a stronger aversive response against overlapping noise. However, we showed that, for both noisy‐ versus quiet‐site individuals, both overlapping and non‐overlapping noise treatments resulted in delayed initiation and disorientation of phonotaxis relative to silent control treatments.

Our study provides the first evidence to demonstrate that, although prior experience appears to mitigate the negative effects of distraction or aversion to noise, prior experience falls short of fully compensating for disrupted orientation through phonotaxis. Additionally, although most studies have emphasized masking of biologically relevant cues and signals as the most prominent mechanism by which noise negatively affects wild organisms, we show that non‐overlapping noise, which cannot cause signal and cue masking, can have negative consequences via distraction or aversive responses. This finding suggests that noise impacts could extend well beyond contexts involving acoustic cue detection and discrimination and deserves increased attention by researchers.

A plain language summary is available for this article.
Grey wolf optimizer: a new strategy to invert geophysical data sets
Authors: Agarwal Aayush , Chandra Akash , Shalivahan Shalivahan , Singh Roshan K
Published: May 2018

There is no meta‐heuristic approach best suited for solving all optimization problems making this field of study highly active. This results in enhancing current approaches and proposing new meta‐heuristic algorithms. Out of all meta‐heuristic algorithms, swarm intelligence is preferred as it can preserve information about the search space over the course of iterations and usually has fewer tuning parameters. Grey Wolves, considered as apex predators, motivated us to simulate Grey Wolves in the optimization of geophysical data sets. The grey wolf optimizer is a swarm‐based meta‐heuristic algorithm, inspired by mimicking the social leadership hierarchy and hunting behaviour of Grey Wolves. The leadership hierarchy is simulated by alpha, beta, delta and omega types of wolves. The three main phases of hunting, that is searching, encircling and attacking prey, is implemented to perform the optimization. To evaluate the efficacy of the grey wolf optimizer, we performed inversion on the total gradient of magnetic, gravity and self‐potential anomalies. The results have been compared with the particle swarm optimization technique. Global minimum for all the examples from grey wolf optimizer was obtained with seven wolves in a pack and 2000 iterations. Inversion was initially performed on thin dykes for noise‐free and noise‐corrupted (up to 20% random noise) synthetic data sets. The inversion on a single thin dyke was performed with a different search space. The results demonstrate that, compared with particle swarm optimization, the grey wolf optimizer is less sensitive to search space variations. Inversion of noise‐corrupted data shows that grey wolf optimizer has a better capability in handling noisy data as compared to particle swarm optimization. Practical applicability of the grey wolf optimizer has been demonstrated by adopting four profiles (i.e. surface magnetic, airborne magnetic, gravity and self‐potential) from the published literature. The grey wolf optimizer results show better data fit than the particle swarm optimizer results and match well with borehole data.
Glycyrrhetic Acid 3‐O‐Mono‐β‐d‐glucuronide (GAMG): An Innovative High‐Potency Sweetener with Improved Biological Activities
Authors: Guo Lichun , Katiyo Wendy , Lu Liushen , Zhang Xuan , Wang Mingming , Yan Jiai , Ma Xiaoyun , Yang Ruijin , Zou Long , Zhao Wei
Published: May 2018

Glycyrrhetic acid 3‐O‐mono‐β‐d‐glucuronide (GAMG) is an important derivative of glycyrrhizin (GL) and has attracted considerable attention, especially in the food and pharmaceutical industries, due to its natural high sweetness and strong biological activities. The biotransformation process is becoming an efficient route for GAMG production with the advantages of mild reaction conditions, environmentally friendly process, and high production efficiency. Recent studies showed that several β‐glucuronidases (β‐GUS) are key GAMG‐producing enzymes, displaying a high potential to convert GL directly into the more valuable GAMG and providing new insights into the generation of high‐value compounds. This review provides details of the structural properties, health benefits, and potential applications of GAMG. The progress in the development of the biotransformation processes and fermentation strategies to improve the yield of GAMG is also discussed. This work further summarizes recent advances in the enzymatic synthesis of GAMG using β‐GUS with emphasis on the physicochemical and biological properties, molecular modifications, and enzymatic strategies to improve β‐GUS biocatalytic efficiencies. This information contributes to a better framework to explore production and application of bioactive GAMG.
Nonthermal Processes for Shelf‐Life Extension of Seafoods: A Revisit
Authors: Olatunde Oladipupo Odunayo , Benjakul Soottawat
Published: May 2018

For the past two decades, consumer demand for minimally processed seafoods with good sensory acceptability and nutritive properties has been increasing. Nonthermal food processing and preservation technologies have drawn the attention of food scientists and manufacturers because nutritional and sensory properties of such treated foods are minimally affected. More importantly, shelf‐life is extended as nonthermal treatments are capable of inhibiting or killing both spoilage and pathogenic organisms. They are also considered to be more energy‐efficient and to yield better quality when compared with conventional thermal processes. This review provides insight into the nonthermal processing technologies currently used for shelf‐life extension of seafoods. Both pretreatments such as acidic electrolyte water and ozonification and processing technologies, including high hydrostatic pressurization, ionizing radiation, cold plasma, ultraviolet light, and pulsed electric fields, as well as packaging technology, particularly modified atmosphere packaging, have been implemented to lower the microbial load in seafood. Thus, those technologies may be the ideal approach for the seafood industry, in which prime quality is maintained and safety is assured for consumers.
Potential Functional Byproducts from Guava Purée Processing
Authors: Lim Si Yi , Tham Paik Yean , Lim Hilary Yi Ler , Heng Wooi Shin , Chang Ying Ping
Published: May 2018

The valorization of guava waste requires compositional and functional studies. We tested three byproducts of guava purée processing, namely refiner, siever, and decanter. We analyzed the chemical composition and quantified the prebiotic activity score and selected carbohydrates; we also determined the water holding (WHC), oil holding (OHC), cation exchange capacities, bile acid binding, and glucose dialysis retardation (GDR) of the solid fraction and the antioxidative and α‐amylase inhibitory capacities (AIC) of the ethanolic extract. Refiner contained 7.7% lipid, 7.08% protein and a relatively high phytate content; it had a high prebiotic activity score and possessed the highest binding capacity with deoxycholic acid. Siever contained high levels of low molecular weight carbohydrates and total tannin but relatively low crude fiber and cellulose contents. It had the highest binding with chenodeoxycholic acid (74.8%), and exhibited the highest 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging capacity. Decanter was rich in cellulose and had a high prebiotic activity score. The WHC and OHC values of decanter were within a narrow range and also exhibited the highest binding with cholic acid (86.6%), and the highest values of GDR and AIC. The refiner waste could be included in animal feed but requires further processing to reduce the high phytate levels. All three guava byproducts had the potential to be a source of antioxidant dietary fiber (DF), a finding that warrants further in vivo study.

Practical Application

To differing extents, the guava byproducts exhibited useful physicochemical binding properties and so possessed the potential for health‐promoting activity. These byproducts could also be upgraded to other marketable products so the manufacturers of processed guava might be able to develop their businesses sustainably by making better use of them.
Characterization of Nanofibrillated Cellulose Produced by Different Methods from Cabbage Outer Leaves
Authors: Khukutapan Donnapa , Chiewchan Naphaporn , Devahastin Sakamon
Published: May 2018

The potential use of cabbage outer leaves as a starting material for the production of nanofibrillated cellulose (NFC) was investigated. Chemical‐free pretreatment methods, namely, autoclaving, ultrasonication (US), and high‐shear homogenization (HS), were applied to remove noncellulosic components from cabbage cell walls prior to defibrillation, which was conducted by subjecting a pretreated sample to HS and then high‐pressure homogenization. The sample undergone autoclaving at 130 °C for 2 hr was noted to contain a significantly higher cellulose content (36.5% dry mass) compared with the fresh leaves (12.48% dry mass). This led to an increase in the crystallinity index (CI) of the autoclaved cabbages from 30.8% to 50.7%. Further increase in the cellulose content (47.0% to 49.2% dry mass) was observed when subjecting the autoclaved sample to either US at 37 kHz for 1 hr, HS at 3800 × g for 15 min or HS followed by US at the aforementioned conditions. After pretreatment and defibrilllation, a suspension of NFC with the diameters of 4 to 50 nm was obtained, with the CI of 59.1% to 66.7%. Such a suspension exhibited a gel‐like behavior with tan δ in the range of 0.12 to 0.13; the suspension exhibited a similar behavior to that prepared by the conventional chemical pretreatment method.

Practical Application

NFC could be produced from cabbage outer leaves, which are an abundantly available by‐product of a vegetable processing plant, via the combined hydrothermal and mechanical pretreatment without the use of any chemicals. This chemical‐free preparation process is highly desirable as it leaves no residues in the product and causes no chemical waste that needs to be treated. Cabbage‐based NFC also exhibits similar characteristics to that prepared via a chemically treated route.
Evaluation of Antioxidant Properties, Phenolic Compounds, Anthelmintic, and Cytotoxic Activities of Various Extracts Isolated from Nepeta cadmea: An Endemic Plant for Turkey
Authors: Kaska Arzu , Deniz Nahide , Çiçek Mehmet , Mammadov Ramazan
Published: May 2018

Nepeta cadmea Boiss. is a species endemic to Turkey that belongs to the Nepeta genus. Several species of this genus are used in folk medicine. This study was designed to investigate the phenolic compounds, antioxidant, anthelmintic, and cytotoxic activities of various extracts (ethanol, methanol, acetone, and water) of N. cadmea. The antioxidant activities of these extracts were analyzed using scavenging methods (DPPH, ABTS, and H2O2 scavenging activity), the β‐carotene/linoleic acid test system, the phosphomolybdenum method, and metal chelating activity. Among the 4 different extracts of N. cadmea that were evaluated, the water extract showed the highest amount of radical scavenging (DPPH, 25.54 μg/mL and ABTS, 14.51 μg/mL) and antioxidant activities (β‐carotene, 86.91%). In the metal chelating and H2O2 scavenging activities, the acetone extract was statistically different from the other extracts. For the phosphomolybdenum method, the antioxidant capacity of the extracts was in the range of 8.15 to 80.40 μg/mg. The phenolic content of the ethanol extract was examined using HPLC and determined some phenolics: epicatechin, chlorogenic, and caffeic acids. With regard to the anthelmintic properties, dose‐dependent activity was observed in each of the extracts of N. cadmea. All the extracts exhibited high cytotoxic activities. The results will provide additional information for further studies on the biological activities of N. cadmea, while also helping us to understand the importance of this species. Furthermore, based on the results obtained, N. cadmea may be considered as a potentially useful supplement for the human diet, as well as a natural antioxidant for medicinal applications.

Practical Application

The plants of the Nepeta genus have been extensively used as traditional herbal medicines. Nepeta cadmea Boiss., one of the species belonging to the Nepeta genus, is a species endemic to Turkey. In our study, we demonstrated the antioxidant capacities, total phenolic, flavonoid, tannin content, anthelmintic, and cytotoxic activities of various extracts of Nepeta cadmea. The present study could well supply valuable data for future investigations and further information on the potential use of this endemic plant for humans, in both dietary and pharmacological applications.
Clinical Predictors of Risk for Decreased Cardiac Tissue Perfusion After Percutaneous Coronary Intervention: A Retrospective Cohort Study
Authors: Monteiro Moreira Francine , Cristina Dias Cunha Nascimento Teresa , Murata Murakami Beatriz , Cristina Bergamasco Ellen , Takao Lopes Camila , Ribeiro dos Santos Eduarda
Published: May 2018

OBJECTIVE

To establish clinical predictors of risk for decreased cardiac tissue perfusion (DCTP) after percutaneous coronary intervention (PCI).

METHODS

Data on demographic, anthropometric, clinical, and procedural variables were collected as explanatory from a database of 1,542 adult patients undergoing PCI. A diagnosis of periprocedural myocardial infarction was used to confirm DCTP. A multivariate logistic regression determined the predictors of DCTP.

RESULTS

The independent predictors of risk for DCTP were age (OR = 1.02, CI 95% = 1.01–1.03, p = .008), multivessel disease (OR = 1.79, CI 95% = 1.30–2.46, p <.001) and intraprocedural lesion complications (OR = 4.56, CI 95% = 3.03–6.87, p <.001).

CONCLUSION AND IMPLICATIONS FOR NURSING PRACTICE

These results increase the level of evidence of risk for DCTP by refining its risk factors and can support nurses’ clinical judgment.
Laparoscopic total gastrectomy for remnant gastric cancer: A single‐institution experience
Authors: Booka Eisuke , Kaihara Masaki , Mihara Koki , Nishiya Shin , Handa Kan , Ito Yasuhiro , Shibutani Shintaro , Egawa Tomohisa , Nagashima Atsushi
Published: May 2018

Introduction

The incidence of remnant gastric cancer is increasing because of past use of subtotal gastrectomy to treat peptic ulcer and increased survival rates after radical gastrectomy for gastric cancer. The feasibility and advantages of laparoscopic total gastrectomy (LTG) for remnant gastric cancer remain unclear. Therefore, we aimed to investigate the safety, feasibility, and clinical short‐term outcomes of LTG for remnant gastric cancer.

Methods

Patients who underwent completion total gastrectomy for remnant gastric cancer between April 2007 and October 2017 were divided into two groups: the open total gastrectomy (OTG) group and the LTG group. Clinicopathological data and short‐term outcomes were analyzed.

Results

A total of 31 remnant gastrectomies (23 OTG, 8 LTG) were performed. Blood loss was significantly lower in the LTG group than in the OTG group (135.5 vs 568.3 mL, P = 0.013). However, there was no significant difference in the operation time, days to food intake, or length of hospital stay between the two groups. Additionally, there was no significant difference in the postoperative complications, number of retrieved lymph nodes, or pathological findings. Two LTG patients (25.0%) required conversion to open surgery. There was no mortality in either group.

Conclusions

LTG for remnant gastric cancer can be a safe treatment option and may have an advantage of less blood loss than OTG.
Laparoscopic nephrectomy in a patient with severe scoliosis: A case report
Authors: Tamura Daichi , Ito Ayato , Kikuchi Daichi , Tsuyukubo Takashi , Kato Renpei , Kato Yoichiro , Konari Susumu , Omori So , Obara Wataru
Published: May 2018

Although the role of laparoscopic nephrectomy (LN) has been established, few studies have reported cases of LN in individuals with scoliosis. Here we report a case of right LN in a patient with severe right convex scoliosis. A 26‐year‐old man presented with a fever. His medical history comprised severe right convex lumbar scoliosis. CT revealed right hydronephrosis and right kidney stones. Pyelonephritis requiring nephrectomy was diagnosed. Right LN was feasible with elaborate perioperative care. The postoperative course was uneventful with no relapse of urinary tract infection.
Laparoscopic abdominoperineal resection with lateral lymph node dissection for advanced rectal and prostate cancer with synchronous lateral lymph node metastases
Authors: Ishikawa Takahisa , Homma Shigenori , Nishikawa Makoto , Nakamoto Hiroki , Yokoyama Ryoji , Taketomi Akinobu
Published: May 2018

Here we report a case of advanced rectal and prostate cancer with synchronous lateral lymph node (LLN) metastases that was treated with laparoscopic surgery. A 71‐year‐old man presented with fecal occult blood and was diagnosed with rectal cancer. A metastatic right LLN was suspected after CT examination of a 19‐mm lymph node (proximal internal iliac artery region) and a 13‐mm lymph node (distal internal iliac artery region) in the right lateral region. We planned neoadjuvant chemotherapy to suppress local and distant recurrence. This treatment decreased the size of the primary rectal tumor. We performed laparoscopic abdominoperineal resection and right LLN dissection. The histopathological diagnosis was LLN metastases from the rectal and prostate cancers. It is rare for synchronous metastases from rectal and prostate cancers to be observed in the LLN. It may be difficult to determine an appropriate treatment strategy in cases like this.
Synthesis and biological evaluation of novel N‐aryl‐ω‐(benzoazol‐2‐yl)‐sulfanylalkanamides as dual inhibitors of α‐glucosidase and protein tyrosine phosphatase 1B
Authors: Wang Mei‐Yan , Cheng Xian‐Chao , Chen Xiu‐Bo , Li Yu , Zang Lan‐Lan , Duan Yu‐Qing , Chen Ming‐Zhu , Yu Peng , Sun Hua , Wang Run‐Ling
Published: May 2018

α‐Glucosidase is known to catalyze the digestion of carbohydrates and release free glucose into the digestive tract. Protein tyrosine phosphatase 1B (PTP1B) is engaged in the dephosphorylation of the insulin receptor and regulation of insulin sensitivity. Therefore, dual antagonists by targeting both α‐glucosidase and PTP1B may be potential candidates for type 2 diabetes therapy. In this work, three series of novel N‐aryl‐ω‐(benzoazol‐2‐yl)‐sulfanylalkanamides were synthesized and assayed for their α‐glucosidase and PTP1B inhibitory activities, respectively. Compound 3l, exhibiting the most effective α‐glucosidase inhibitory activity (IC50 = 10.96 μm (3l), IC50 = 51.32 μm (Acarbose), IC50 = 18.22 μm (Ursolic acid)) and potent PTP1B inhibitory activity (IC50 = 13.46 μm (3l), IC50 = 14.50 μm (Ursolic acid)), was identified as a novel dual inhibitor of α‐glucosidase and PTP1B. Furthermore, 3l is a highly selective PTP1B inhibitor because no inhibition was showed by 3l at 100 μm against PTP‐MEG2, TCPTP, SHP2, or SHP1. Subsequent kinetic analysis revealed 3l inhibited α‐glucosidase in a reversible and mixed manner. Molecular docking study indicated that hydrogen bonds, van der Waals, charge interactions and Pi‐cation interactions all contributed to affinity between 3l and α‐glucosidase/PTP1B.