bluuebunny/crossref_metadata_2025 huggingface dataset:
The biochar dilemma
Authors: Mukherjee A. , Lal R.
Published: March 2014

Any strategy towards widespread adoption of biochar as a soil amendment is constrained by the scarcity of field-scale data on crop response, soil quality and environmental footprint. Impacts of biochar as a soil amendment over a short period based on laboratory and greenhouse studies are often inconclusive and contradictory. Yet biochar is widely advocated as a promising tool to improve soil quality, enhance C sequestration, and increase agronomic yield. While substantial reviews exist on positive aspects of biochar research, almost no review to date has compiled negative aspects of it. Although biochar science is advancing, available data indicate several areas of uncertainty. This article reviews a range of negative impacts of biochar on soil quality, crop yield, and associated financial risk. This review is important because advances in biochar research demand identification of the risks (if any) of using biochar as a soil amendment before any large-scale field application is recommended. It is the first attempt to acknowledge such issues with biochar application in soil. Thus, the aims of this review are to assess the uncertainties of using biochar as a soil amendment, and to clarify ambiguity regarding interpretation of research results. Along with several unfavourable changes in soil chemical, physical and biological properties, reduction in crop yield has been reported. Relative to controls, the yield for biochar-amended soil (application rate 0.2–20% w/w) has been reduced by 27, 11, 36, 74, and 2% for rice (Oryza sativa L.) (control 3.0 Mg ha–1), wheat (Triticum spp. L.) (control 4.6 Mg ha–1), maize (Zea mays L.) (control 4.7 Mg ha–1), lettuce (Lactuca sativa L.) (control 5.4 Mg ha–1), and tomato (Solanum lycopersicum L.) (control 265 Mg ha–1), respectively. Additionally, compared with unamended soils, gaseous emissions from biochar-amended soils (application rate 0.005–10% w/w) have been enhanced up to 61, 152 and 14% for CO2 (control 9.7 Mg ha–1 year–1), CH4 (control 222 kg ha–1 year–1), and N2O (control 4.3 kg ha–1 year–1), respectively. Although biochar has the potential to mitigate several environmental problems, the data collated herein indicate that a systematic road-map for manufacturing classification of biochars, and cost–benefit analysis, must be developed before implementation of field-scale application.
Abscisic acid sensor RCAR7/PYL13, specific regulator of protein phosphatase coreceptors
Authors: Fuchs Stefan , Tischer Stefanie V. , Wunschel Christian , Christmann Alexander , Grill Erwin
Published: April 2014

Significance

The plant hormone abscisic acid (ABA) acts both as a developmental signal and as an integrator of environmental cues such as drought and cold. ABA perception recruits an ABA-binding regulatory component [regulatory component of ABA receptor (RCAR)/PYR1/PYL] and an associated protein phosphatase 2C (PP2C). Phytohormone binding to the RCAR inactivates the phosphatase activity of the coreceptor, permitting phosphorelay of the ABA signal via downstream protein kinases. The amino acid residues of the ABA-binding pocket are conserved among RCAR members; however, RCAR7 has several changes in these residues, and its function as an ABA receptor has remained elusive. Here we show a bona fide ABA receptor function for RCAR7 and identify structural constraints that contribute to specific pairing of RCAR7 with PP2Cs.
Notes on teaching Chinese to foreign learners
Authors: Halliday M.A.K.
Published: April 2014

Recently there has been considerable discussion over “how to teach Chinese to foreign learners”. This article investigates the common problems which Chinese teachers encounter in teaching Chinese to the speakers of English. It points out that (1) for foreign adult learners who are just starting out to learn Chinese, the best teachers are those who speak the same language as their students do rather than native Chinese teachers; (2) the later the students start learning Chinese characters, the faster and easier for them to pick up the language, and hence, Chinese characters should not be introduced at the early stage; and (3) one should aim at achieving phonological accuracy in Chinese.
Collective Security
Authors: Abass Ademola
Published: March 2014

The term collective security in a general sense is given many understandings both professional and nonprofessional. The phrase is sometimes used to describe the organization of security on a “collective” basis. Often, it is used to denote the “collective organization” of security. While neither of these uses is inherently wrong, neither succinctly captures what “collective security” implies when used by international lawyers. In international law, collective security is a term connoting something more dense and intricate, and much more slippery, than the above more straightforward expressions. The notion of collective security, its premise, and objectives are deeply contested by states and scholars. It is universally acknowledged that collective security is today organized under the United Nations; however, regional organizations, which used to focus primarily on economic matters, have attained greater prominence in collective security efforts especially since the end of the Cold War. This article examines the definition of collective security, its features and objectives, the actors that have the responsibility for operating it globally and regionally, its various manifestations, its limitations and, above all, its role in future.
Experimental determination of refractive index of condensed reflectin in squid iridocytes
Authors: Ghoshal Amitabh , DeMartini Daniel G. , Eck Elizabeth , Morse Daniel E.
Published: April 2014

Loliginid squid dynamically tune the structural iridescence of cells in their skin for active camouflage and communication. Bragg reflectors in these cells consist of membrane-bound lamellae periodically alternating with low refractive index extracellular spaces; neuronal signalling induces condensation of the reflectin proteins that fill the lamellae, consequently triggering the expulsion of water. This causes an increase in refractive index within the lamellae, activating reflectance, with the change in lamellar thickness and spacing progressively shifting the wavelength of reflected light. We used micro-spectrophotometry to measure the functionally relevant refractive index of the high-index lamellae of the Bragg reflectors containing the condensed reflectins in chemically fixed dermal iridocytes of the squid,Doryteuthis opalescens. Our high-magnification imaging spectrometer allowed us to obtain normalized spectra of optically distinct sections of theindividual, subcellular, multi-layer Bragg stacks. Replacement of the extracellular fluid with liquids of increasing refractive index allowed us to measure the reflectivity of the Bragg stacks as it decreased progressively to 0 when the refractive index of the extracellular medium exactly matched that of the reflectin-filled lamellae, thus allowing us to directly measure the refractive index of the reflectin-filled lamellae asncondensed lamellae≈ 1.44. The measured value of the physiologically relevantncondensed lamellaefrom these bright iridocytes falls within the range of values that we recently determined by an independent optical method and is significantly lower than values previously reported for dehydrated and air-dried reflectin films. We propose that this directly measured value for the refractive index of the squid's Bragg lamellae containing the condensed reflectins is most appropriate for calculations of reflectivity in similar reflectin-based high-index layers in other molluscs.
Flexible analysis of transcriptome assemblies with Ballgown
Authors: Frazee Alyssa C , Pertea Geo , Jaffe Andrew E , Langmead Ben , Salzberg Steven L , Leek Jeffrey T
Published: March 2014

We have built a statistical package called Ballgown for estimating differential expression of genes, transcripts, or exons from RNA sequencing experiments. Ballgown is designed to work with the popular Cufflinks transcript assembly software and uses well-motivated statistical methods to provide estimates of changes in expression. It permits statistical analysis at the transcript level for a wide variety of experimental designs, allows adjustment for confounders, and handles studies with continuous covariates. Ballgown provides improved statistical significance estimates as compared to the Cuffdiff differential expression tool included with Cufflinks. We demonstrate the flexibility of the Ballgown package by re-analyzing 667 samples from the GEUVADIS study to identify transcript-level eQTLs and identify non-linear artifacts in transcript data. Our package is freely available from: https://github.com/alyssafrazee/ballgown
Histone variants: dynamic punctuation in transcription
Authors: Weber Christopher M. , Henikoff Steven
Published: April 2014

Eukaryotic gene regulation involves a balance between packaging of the genome into nucleosomes and enabling access to regulatory proteins and RNA polymerase. Nucleosomes are integral components of gene regulation that restrict access to both regulatory sequences and the underlying template. Whereas canonical histones package the newly replicated genome, they can be replaced with histone variants that alter nucleosome structure, stability, dynamics, and, ultimately, DNA accessibility. Here we consider how histone variants and their interacting partners are involved in transcriptional regulation through the creation of unique chromatin states.
SPX4 Negatively Regulates Phosphate Signaling and Homeostasis through Its Interaction with PHR2 in Rice
Authors: Lv Qundan , Zhong Yongjia , Wang Yuguang , Wang Zhiye , Zhang Li , Shi Jing , Wu Zhongchang , Liu Yu , Mao Chuanzao , Yi Keke , Wu Ping
Published: April 2014

PHR2, a central regulator of phosphate signaling in rice, enhanced the expression of phosphate starvation-induced (PSI) genes and resulted in the enhancement of Pi acquisition under Pi deficiency stress. This occurred via PHR2 binding to a cis-element named the PHR1 binding sequences. However, the transcription level of PHR2 was not responsive to Pi starvation. So how is activity of transcription factor PHR2 adjusted to adapt diverse Pi status? Here, we identify an SPX family protein, Os-SPX4 (SPX4 hereafter), involving in Pi starvation signaling and acting as a negative regulator of PHR2. SPX4 is shown to be a fast turnover protein. When Pi is sufficient, through its interaction with PHR2, SPX4 inhibits the binding of PHR2 to its cis-element and reduces the targeting of PHR2 to the nucleus. However, when plants grow under Pi deficiency, the degradation of SPX4 is accelerated through the 26S proteasome pathway, thereby releasing PHR2 into the nucleus and activating the expression of PSI genes. Because the level of SPX4 is responsive to Pi concentration and SPX4 interacts with PHR2 and regulates its activity, this suggests that SPX4 senses the internal Pi concentration under diverse Pi conditions and regulates appropriate responses to maintain Pi homeostasis in plants.
The experience of New Zealand in the evolving wine markets of Japan and Singapore
Authors: Rod Michel , Beal Tim
Published: April 2014

Purpose

– The purpose of this paper is to explore the developing wine markets of Japan and Singapore for New Zealand (NZ) wine. It is principally an opinion piece with some reference to the academic literature, to the trade literature and quite a bit of the authors' own experiences as marketing academics conducting research in East Asia on the growth of wine drinking in this region of the globe.

Design/methodology/approach

– This paper is atypical in that it is more of a descriptive commentary, or “Viewpoint”, that draws on the literature interspersed with the autoethnographic reflections regarding the experiences in looking at NZ wine in Japan and Singapore as well as drawing on data from face-to-face interviews and focus groups with a variety of participants with knowledge of the global wine industry. Informal meetings were held with individuals representing NZ wineries, Japanese and Singapore wine distributors, restaurant food and beverage managers, wine journalists, wine shop proprietors and sommeliers data. Personal reflections and opinions are interspersed with the trade and academic literature in relation to the exploration of the NZ experience in the wine markets of Japan and Singapore.

Findings

– The major finding is that there are marked differences between Japanese and Singaporean consumers and that the adoption of wine drinking or the incorporation of wine into one's non-traditionally wine-drinking society involves individuals who play cultural intermediary roles as communicators and distributors of “cultural products” and as translators of cultural products into meaningful local, consumption experiences. Based on personal observations, there appears to be a functional aspect to this facet of globalisation in that cultural intermediaries facilitate the adoption of wine consumption in emerging Asian markets simply through promoting it as a social accompaniment much like local alcoholic beverages, but also that wine has the capacity to enhance local cuisine.

Practical implications

– The insights gained through personal reflection and an examination of perspectives from participants with knowledge of the wine industry in Japan and Singapore should help NZ wine producers with specific knowledge to navigate through the complexity of emerging wine markets in the Asian context.

Originality/value

– The contribution is in looking at “sophisticated globalization” in the context of NZ wine producers looking to market a cultural product such as wine to specific Asian societies not traditionally known for wine drinking.
Novel measures for emission reduction in supply chains
Authors: Frizelle Gerry , Casali Ivian
Published: April 2014

Purpose

– The purpose of this paper is to look at how novel measures of supply chain performance can be used to identify unnecessary waste in terms of under-loaded vehicles and extended delivery times, along with their causes. In particular it focuses on problems that can be tackled without the need for capital expenditure. The measures go under the collective name of “turbulence”. This represents the chain deviating from its goals. Quantifying unnecessary waste then allows unnecessary carbon emissions to be estimated while pointing to what changes will have the biggest impact. The measures have been used by three companies and some early results are provided.

Design/methodology/approach

– The approach was first to use evidence from the literature to show the value of having a new measure. Next the creation of one specific new measure, called relative turbulence, a relative measure for the more general concept of turbulence. Third testing it in the field with data from companies. Then showing how carbon emissions can be derived.

Findings

– The first finding is that the analysis can pinpoint sources of unnecessary emissions. Second the results suggest excessive emissions arise both though poor planning and poor practice. Third that there is a need for two models – from the users’ viewpoint and the carriers’ viewpoint. Finally the approach can be used with field data that is currently available, thus avoiding expensive one-off studies.

Research limitations/implications

– The main research implication is that entropic measures are useful and can provide fresh insights. Being generic they may be applicable in other contexts. However, they can be mathematically tricky to use.

Practical implications

– The analysis has been tested in companies and findings are included in the paper. They provide an insight that is not available solely from current measures. Businesses cannot only measure emissions but start to pinpoint causes.

Originality/value

– The main areas of original contributions are in the introduction of a new measure, based on entropic principles, particularly the one called relative turbulence. The second is juxtaposing this measure with standard measures to gain new insights. Finally the idea that supply networks can be built from, what is called the irreducible chain.
Step change-point estimation of multivariate binomial processes
Authors: Niaki S.T.A. , Khedmati Majid
Published: March 2014

Purpose

– The purpose of this paper is to propose two control charts to monitor multi-attribute processes and then a maximum likelihood estimator for the change point of the parameter vector (process fraction non-conforming) of multivariate binomial processes.

Design/methodology/approach

– The performance of the proposed estimator is evaluated for both control charts using some simulation experiments. At the end, the applicability of the proposed method is illustrated using a real case.

Findings

– The proposed estimator provides accurate and useful estimation of the change point for almost all of the shift magnitudes, regardless of the process dimension. Moreover, based on the results obtained the estimator is robust with regard to different correlation values.

Originality/value

– To the best of authors’ knowledge, there are no work available in the literature to estimate the change-point of multivariate binomial processes.
Shariah-compliance and value of analysts' recommendations: evidence from the MENA region
Authors: Farooq Omar
Published: March 2014

Purpose

– The purpose of this paper is to document the performance of analysts' recommendations for shariah-compliant firms and non-shariah-compliant firms in the MENA region during the period between 2005 and 2009.

Design/methodology/approach

– This paper uses post-recommendation market-adjusted returns as a measure of performance and computes returns for different holding periods. Significant positive (negative) returns following buy (sell) recommendation will indicate value relevance of these recommendations.

Findings

– The results show that analysts are not able to make any value relevant recommendations for shariah-compliant firms. The author documents insignificant returns following analysts' buy and sell recommendations for shariah-compliant firms. In contrast to their performance for shariah-compliant firms, the results show that analysts are able to produce value relevant recommendations for non-shariah-complaint firms. The author reports significant returns following analysts' buy recommendations for non-shariah-complaint firms. The author also reports significantly positive spread between returns following analysts' buy and sell recommendations for non-shariah-compliant firms. Positive spread indicates that analysts are able to differentiate between well-performing and badly-performing non-shariah-compliant firms. Interestingly, in case of sell recommendations, the results show no significant value in analysts' sell recommendations for non-shariah-complaint firms.

Practical implications

– The results imply that investors should not blindly follow analyst recommendations for shariah-compliant firms while making their investment decisions in the MENA region.

Originality/value

– This paper makes detailed analysis of analyst recommendations for shariah-compliant firms and non-shariah-compliant firms in previously unexplored MENA region.
The socioeconomic impacts of local energy programmes: a case study of Avrig, Romania
Authors: Miron Ramona
Published: March 2014

Purpose

– The purpose of this paper is to investigate the expected economic and social effects of the “Local Energy Plan” – a programme of the local administration that aims to transform the Romanian town Avrig until 2020 into an energy independent town relying exclusively on renewable energy resources.

Design/methodology/approach

– The study uses a mixed-method approach to investigate the effects of a small town's transition to renewable energy. This approach consists of a series of in-depth interviews with the local authorities, investors, other representatives of the business sector and citizens of Avrig and economic modelling to determine the direct effects generated by the implementation of different renewable energy projects.

Findings

– The results of this study show that transitioning to renewable energy could have a significant positive impact on the town's economy, however, improvements of the Local Energy Plan are needed especially regarding the planned capacities and the involvement of the local community.

Practical implications

– While investigating, through in-depth interviews, the overall perceptions and attitudes of the different stakeholders regarding the transition of the town to renewable energy a communication gap has been observed. The study may represent a turning point for the local administrations strategy towards its energy goals.

Originality/value

– Combining economic modelling and quantitative research methods this paper provides a holistic image of the socioeconomic impacts of the Local Energy Plan in the small town Avrig. The results and suggestions could contribute to the successful transition to renewable energy of Avrig.
Clear skies or cloudy forecast?
Authors: Goh Elaine
Published: April 2014

Purpose

– Using the example of audiovisual materials, this paper aims to illustrate how records-related and archival legislation lags behind advances in technology. As more audiovisual materials are created on the cloud, questions arise about the applicability of national laws over the control, ownership, and custody of data and records.

Design/methodology/approach

– This paper analyses court cases relating to audiovisual materials in the cloud and archival legislation from three Commonwealth countries: Canada, Australia, and Singapore – representing North America, the Pacific, and Asia respectively.

Findings

– Current records-related and archival legislation does not effectively address the creation, processing, and preservation of records and data in a cloud environment. The paper identifies several records-related risks linked to the cloud – risks related to the ownership and custody of data, legal risks due to transborder data flow, and risks due to differing interpretations on the act of copying and ownership of audiovisual materials.

Research limitations/implications

– The paper identifies the need for records professionals to pay greater attention to the implications of the emerging cloud environment. There is a need for further research on how the concept of extraterritoriality and transborder laws can be applied to develop model laws for the management and preservation of records in the cloud.

Originality/value

– The paper identifies record-related risks linked to the cloud by analyzing court cases and archival legislation. The paper examines maritime law to find useful principles that the archival field could draw on to mitigate some of these risks.
The impact of information culture on information/records management
Authors: Svärd Proscovia
Published: April 2014

Purpose

–The purpose of this article is to examine the information culture of a medium-sized municipality in Belgium. Public information/records is/are one of the most important instruments of citizens' control of public authorities. The principle of Public Access gives citizens a right to access public records, while the Privacy Act protects the integrity of the citizens. Municipalities are institutions that intensely interact with the citizens. Therefore, the way they handle the information that is generated during this interaction is of crucial importance to the efficient service delivery, safeguarding the rights of the citizens that they serve and for sustaining the open governance structure that promotes the principles of accountability and transparency.

Design/methodology/approach

–The author employed a case study approach in order to establish the attitudes and norms the organizational employees had towards the management of information/records. She also applied the information culture assessment framework developed by Oliver during the design of the research questions.

Findings

–Information culture affects the way public information/records are managed. Though investments are being made in information systems to facilitate the capture and management of information/records, the people issues are equally as crucial. E-Government development will require an information culture that promotes effective creation, use and management of information, if its goal of efficient and transparent public administrations is to be achieved.

Originality/value

–The originality of this study lies in the application of the information culture assessment framework that was developed by Oliver. The framework facilitates the formulation of questions using its three layers to tease out the information required by a researcher in an attempt to draw conclusions regarding the attitudes, norms and the value the interviewees attach to information/records.
India: MNC strategies for growth and innovation
Authors: Leavy Brian
Published: April 2014

Purpose

– Companies with global ambitions need to pay close attention to how innovation is achieved in India. In particular, corporate leaders still have much to learn about how this economic powerhouse is likely to develop in the coming decades and what strategy and innovation plays are most likely to be successful.

Design/methodology/approach

– This “Masterclass” examines the lessons from three important recent books that offer valuable insights on how Indian businesses are addressing the innovation challenge: Conquering the Chaos by Ravi Venkatesan, former Chairman of Cummins India and Microsoft India, identifies the leadership blueprint for creating most value in this and similar emerging “VUCCA” markets. India Inside by Nirmalya Kumar and Phanish Puranam discovers a significant opportunity and challenge – India's rapid emergence as a global hub of innovation. Reverse Innovation by Vijay Govindarajan and Chris Trimble presents an alternative strategy to “glocalization” as a more promising way to drive global growth, using emerging markets like India as the innovation platform.

Findings

– The article looks at why only 25 to 30 of the more than 1,300 major multinationals currently operating in India have made it into the “high-growth trajectory, market leadership” category within that country.

Practical implications

– Every company with global ambitions would now be well advised to make to make innovation in India central to their own ambitions, so that they might become the global disruptors of the future not the victims.

Originality/value

– While most of today's multinational CEOs see pursuing significant market participation in China as a “no-brainer,” rising, or failing to rise, to the challenge of India, with at least as much urgency and commitment, may turn out to be their most “defining” strategic legacy.
Tumbling Political Theory
Authors: Kohen Ari
Published: March 2014

Blogging in the classroom is not a new idea, but my students have tended to view the blogging assignment negatively, as a homework assignment that simply needed to be done each week and then forgotten until the next time they were required to visit the blog. With that in mind, I decided to employ a very different method of educational blogging – using the Tumblr platform – in which each student would take ownership of his or her own blog and which would make the best possible use of social networking technology to boost interaction among the students and engagement with the course material.
Influence of Velocity on Variability in Gait Kinematics: Implications for Recognition in Forensic Science
Authors: Yang Sylvia X. M. , Larsen Peter K. , Alkjær Tine , Lynnerup Niels , Simonsen Erik B.
Published: March 2014

Closed circuit television (CCTV) footage is often available from crime scenes and may be used to compare perpetrators with suspects. Usually, the footage comprises incomplete gait cycles at different velocities, making gait pattern identification from crimes difficult. This study investigated the concurrence of joint angles throughout a gait cycle at three different velocities (3.0, 4.5, 6.0 km/h). Six datasets at each velocity were collected from 16 men. A variability range VR throughout the gait cycle at each velocity for each joint angle for each person was calculated. The joint angles at each velocity were compared pairwise, and whenever this showed values within the VR of this velocity, the case was positive. By adding the positives throughout the gait cycle, phases with high and low concurrences were located; peak concurrence was observed at mid‐stance phase. Striving for the same velocity for the suspect and perpetrator is recommended.
Time course of intestinal barrier function injury in a sodium taurocholate‐induced severe acute pancreatitis in rat model
Authors: Liang Hong Yin , Chen Tao , Wang Tao , Huang Zhu , Yan Hong Tao , Tang Li Jun
Published: April 2014

Objective

The aims of this study were to clarify the kinetics of intestinal barrier function impairment in sodium taurocholate‐induced severe acute pancreatitis (SAP) models and to explore an appropriate concentration of sodium taurocholate and a suitable time point for further study.

Methods

In total, 104 rats were randomly divided into four groups: the normal control group (n = 8) receiving no treatment, the sham‐operation group (n = 32), the 2.5% and 5% sodium taurocholate‐treated SAP groups (n = 32 for each group) which were induced via a retrograde injection of 2.5% or 5% sodium taurocholate into the pancreatic duct. Histological examination, serum D‐lactate and endotoxin levels and the incidence of bacteria translocation were recorded to assess the intestinal mucosal injury.

Results

Pancreatitis models were successfully established in both the 2.5% and 5% sodium taurocholate‐treated groups. The dosage of sodium taurocholate used to induce pancreatitis was positively correlated with the degree of intestinal mucosal injury. The most severe damage to intestinal barrier was observed 24 h after surgery in the 2.5% sodium taurocholate‐treated group and 48 h after surgery in the 5% sodium taurocholate‐treated group, respectively.

Conclusion

Based on the success rate of the model, the mortality and the impairment of intestinal barrier function, we conclude that 24 h after a retrograde injection of 2.5% sodium taurocholate may be the most appropriate time point to study intestinal barrier injury in SAP rats.
HIV‐1 Infection: The Role of the Gastrointestinal Tract
Authors: Cavarelli Mariangela , Scarlatti Gabriella
Published: April 2014

The intestinal mucosa has an important role as portal of entry during mother‐to‐child transmission of HIV‐1 and during sexual transmission. Tissue morphology and integrity, as well as distribution of relevant cell types within the mucosa, spanning from the oropharynx to the rectum, can greatly influence viral infection, replication, presentation, and persistence. The relative contribution to transmission by cell‐associated or cell‐free virus is still not defined for the different routes of transmission. Although the main target cells for HIV‐1 replication are the CD4+ T lymphocytes, which are rapidly depleted both in the periphery and in the mucosal tissues, dendritic cells, Langerhans' cells, and macrophages are players in each of these processes. The predominant cells involved may differ according to the tract of the gut and the route of transmission. The microenvironment of the intestinal mucosa, including mucus, antibodies, or chemo‐cytokines, can as well influence infection and replication of the virus: their role is still under investigation. The understanding of these processes may help in developing efficient prevention strategies.
Loss of B‐cell translocation gene 2 expression in estrogen receptor‐positive breast cancer predicts tamoxifen resistance
Authors: Takahashi Maiko , Hayashida Tetsu , Okazaki Hiroshi , Miyao Kazuhiro , Jinno Hiromitsu , Kitagawa Yuko
Published: April 2014

B‐cell translocation gene 2 (BTG2), a gene suppressed in a subset of aggressive breast cancer, is repressed by estrogen. BTG2 inhibits the expression of HER ligands and promotes AKT activation, which plays an essential role in the tamoxifen resistance of estrogen receptor (ER)‐positive breast cancer. To determine if BTG2 expression modifies tamoxifen efficacy, a cohort of 60 patients treated with adjuvant tamoxifen monotherapy was analyzed. We found that increased BTG2 expression showed better clinical survival and was the only independent prognostic factor for disease‐free survival (hazard ratio, 0.691; 95% confidence interval, 0.495–0.963; P = 0.029). Tamoxifen suppressed the human epidermal growth factor receptor 2 (HER2)‐Akt signaling in BTG2 expressing ER‐positive breast cancer cells with a correlated increase in sensitivity, whereas BTG2 knockdown abrogated this sensitivity. Consistent with this observation, tamoxifen significantly suppressed the growth ratio, tumor weight and Ki‐67 expression in BTG2 expressing breast cancer xenografts in mice. These studies demonstrate that BTG2 is a significant factor in tamoxifen response, acting through modification of AKT activation in ER‐positive/HER2‐negative breast cancer.
Influence of non‐steroidal anti‐inflammatory drugs (NSAIDs) on osseointegration of dental implants in rabbit calvaria
Authors: Cai Wei Xin , Ma Li , Zheng Li Wu , Kruse‐Gujer Astrid , Stübinger Stefan , Lang Niklaus P. , Zwahlen Roger A.
Published: March 2014

Aim

Until recently, adverse effects of non‐steroidal anti‐inflammatory drugs (NSAIDs) on osseointegration of dental implants were unknown. Hence, this study investigated the short‐ and long‐term effects of a 7‐day regimen of parecoxib and diclofenac sodium on osseointegration of dental implants in calvarial bone.

Material and methods

Eighteen New Zealand White rabbits were randomly allocated into three groups (each n = 6): Control group with no postoperative pain killers (Group A), diclofenac group (Group B) and parecoxib group (Group C). In each animal, one dental implant was placed into the calvarial bone (total n = 18). Three rabbits from each group were sacrificed in Week 4. The other three rabbits from each group were sacrificed in Week 12 postoperatively. The implant together with the calvarial bone and dura mater was harvested and subjected to micro‐computed tomography (micro‐CT) and histomorphometric analysis.

Results

Quantitative analysis of micro‐CT data and histomorphometric data neither revealed any statistically significant (P ≤ 0.05) differences between the three different groups related to osseointegration nor between different time points of observation.

Conclusion

In rabbits, a 7‐day regimen of appropriate doses of diclofenac sodium and parecoxib did not adversely affect osseointegration of dental implants and bone healing in calvaria, neither short nor long term (12 weeks).
Dual regulatory switch confers tighter control on HtrA2 proteolytic activity
Authors: Singh Nitu , D'Souza Areetha , Cholleti Anuradha , Sastry G. Madhavi , Bose Kakoli
Published: April 2014

High‐temperature requirement protease A2 (HtrA2), a multitasking serine protease that is involved in critical biological functions and pathogenicity, such as apoptosis and cancer, is a potent therapeutic target. It is established that the C‐terminal post‐synaptic density protein, Drosophila disc large tumor suppressor, zonula occludens‐1 protein (PDZ) domain of HtrA2 plays pivotal role in allosteric modulation, substrate binding and activation, as commonly reported in other members of this family. Interestingly, HtrA2 exhibits an additional level of functional modulation through its unique N‐terminus, as is evident from ‘inhibitor of apoptosis proteins’ binding and cleavage. This phenomenon emphasizes multiple activation mechanisms, which so far remain elusive. Using conformational dynamics, binding kinetics and enzymology studies, we addressed this complex behavior with respect to defining its global mode of regulation and activity. Our findings distinctly demonstrate a novel N‐terminal ligand‐mediated triggering of an allosteric switch essential for transforming HtrA2 to a proteolytically competent state in a PDZ‐independent yet synergistic activation process. Dynamic analyses suggested that it occurs through a series of coordinated structural reorganizations at distal regulatory loops (L3, LD, L1), leading to a population shift towards the relaxed conformer. This precise synergistic coordination among different domains might be physiologically relevant to enable tighter control upon HtrA2 activation for fostering its diverse cellular functions. Understanding this complex rheostatic dual switch mechanism offers an opportunity for targeting various disease conditions with tailored site‐specific effector molecules.

Structured digital abstract

HtrA2 cleaves beta casein by enzymatic study (1, 2, 3)

HtrA2 binds to XIAP-BIR2 by surface plasmon resonance (View interaction)

HtrA2 binds to XIAP-BIR2 pep by surface plasmon resonance (View interaction)

HtrA2 binds to XIAP-BIR3 by surface plasmon resonance (View interaction)

HtrA2 binds to XIAP-BIR3 pep by surface plasmon resonance (View interaction)

XIAP binds to HtrA2 by pull down (View interaction)

XIAP-BIR2 binds to HtrA2 by pull down (View interaction) (View interaction)

XIAP-BIR3 binds to HtrA2 by pull down (View interaction) (View interaction) (View interaction)
Glycyrrhizin inhibits the inflammatory response in mouse mammary epithelial cells and a mouse mastitis model
Authors: Fu Yunhe , Zhou Ershun , Wei Zhengkai , Liang Dejie , Wang Wei , Wang Tiancheng , Guo Mengyao , Zhang Naisheng , Yang Zhengtao
Published: April 2014

Glycyrrhizin, a triterpene glycoside isolated from licorice root, is known to have anti‐inflammatory activities. However, the effect of glycyrrhizin on mastitis has not been reported. The purpose of this study was to investigate the anti‐inflammatory effect and mechanism of action of glycyrrhizin on lipopolysaccharide (LPS)‐induced mastitis in mouse. An LPS‐induced mouse mastitis model was used to confirm the anti‐inflammatory activity of glycyrrhizin in vivo. Primary mouse mammary epithelial cells were used to investigate the molecular mechanism and targets of glycyrrhizin. In vivo, glycyrrhizin significantly attenuated the mammary gland histopathological changes, myeloperoxidase activity and infiltration of neutrophilic granulocytes and downregulated the expression of tumor necrosis factor‐α, interleukin (IL)‐1β and IL‐6 caused by LPS. In vitro, glycyrrhizin dose‐dependently inhibited the LPS‐induced expression of tumor necrosis factor‐α, IL‐6, and RANTES. Western blot analysis showed that glycyrrhizin suppressed LPS‐induced nuclear factor‐κB and interferon regulatory factor 3 activation. However, glycyrrhizin did not inhibit nuclear factor‐κB and interferon regulatory factor 3 activation induced by MyD88‐dependent (MyD88, IKKβ) or TRIF‐dependent (TRIF, TBK1) downstream signaling components. Moreover, glycyrrhizin did not act though affecting the function of CD14 or expression of Toll‐like receptor 4. Finally, we showed that glycyrrhizin decreased the levels of cholesterol of lipid rafts and inhibited the translocation of Toll‐like receptor 4 to lipid rafts. Moreover, glycyrrhizin activated ATP‐binding cassette transporter A1, which could induce cholesterol efflux from lipid rafts. In conclusion, we find that the anti‐inflammatory effects of glycyrrhizin may be attributable to its ability to activate ATP‐binding cassette transporter A1. Glycyrrhizin might be a useful therapeutic reagent for the treatment of mastitis and other inflammatory diseases.
Distinct biochemical properties of human serine hydroxymethyltransferase compared with the Plasmodium enzyme: implications for selective inhibition
Authors: Pinthong Chatchadaporn , Maenpuen Somchart , Amornwatcharapong Watcharee , Yuthavong Yongyuth , Leartsakulpanich Ubolsree , Chaiyen Pimchai
Published: April 2014

Serine hydroxymethyltransferase (SHMT) catalyzes the transfer of a hydroxymethyl group from l‐serine to tetrahydrofolate to yield glycine and 5,10‐methylenetetrahydrofolate. Our previous investigations have shown that SHMTs from Plasmodium spp. (P. falciparum, Pf; P. vivax, Pv) are different from the enzyme from rabbit liver in that Plasmodium SHMT can use d‐serine as a substrate. In this report, the biochemical and biophysical properties of the Plasmodium and the human cytosolic form (hcSHMT) enzymes including ligand binding and kinetics were investigated. The data indicate that, similar to Plasmodium enzymes, hcSHMT can use d‐serine as a substrate. However, hcSHMT displays many properties that are different from those of the Plasmodium enzymes. The molar absorption coefficient of hcSHMT‐bound pyridoxal‐5′‐phosphate (PLP) is much greater than PvSHMT‐bound or PfSHMT‐bound PLP. The binding interactions of hcSHMT and Plasmodium SHMT with d‐serine are different, as only the Plasmodium enzyme undergoes formation of a quinonoid‐like species upon binding to d‐serine. Furthermore, it has been noted that hcSHMT displays strong substrate inhibition by tetrahydrofolate (THF) (at THF > 40 μm), compared with SHMTs from Plasmodium and other species. The pH–activity profile of hcSHMT shows higher activities at lower pH values corresponding to a pKa value of 7.8 ± 0.1. Thiosemicarbazide reacts with hcSHMT following a one‐step model [k1 of 12 ± 0.6 m−1·s−1 and k−1 of (1.0 ± 0.6) × 10−3 s−1], while the same reaction with PfSHMT involves at least three steps. All data indicated that the ligand binding environment of SHMT from human and Plasmodium are different, indicating that it should be possible to develop species‐selective inhibitors in future studies.

Database

serine hydroxymethyltransferase, EC 2.1.2.1; 5,10‐methylenetetrahydrofolate dehydrogenase, EC 1.5.1.5
Pediatric Post‐Traumatic Headaches and Peripheral Nerve Blocks of the Scalp: A Case Series and Patient Satisfaction Survey
Authors: Dubrovsky Alexander Sasha , Friedman Debbie , Kocilowicz Helen
Published: April 2014

Objective

This study's objective is to characterize the therapeutic effect of peripheral nerve blocks of the scalp for children and adolescents with post‐traumatic headaches.

Background

Headaches are the most frequently reported persistent symptoms following a pediatric mild traumatic brain injury, may be challenging to treat, and can transform into debilitating chronic headaches. The beneficial use of peripheral nerve blocks of the scalp has been reported for adults with post‐traumatic headaches.

Methods

Retrospective case series on all patients <18 years of age treated between January 2012 and June 2013 in the mild traumatic brain injury clinic with a nerve block. The main outcome measure was the proportion of patients with a good therapeutic effect, defined by the duration of the block being >24 hours and/or repeat blocks requested. A data extractor blinded to main outcome measures performed the chart review. A patient satisfaction survey was also sent to all patients to assess the recalled experience with the interventions received.

Results

A total of 62 nerve blocks were performed on 28 patients for 30 injuries that led to post‐traumatic headaches. The mean (standard deviation) age was 14.6 (1.7) years. The first nerve blocks were performed a mean (standard deviation) of 70 (54.2) days post‐injury. The therapeutic effect was good in 93% of patients with 71% reporting immediate complete relief of their headaches; the mean percent headache reduction was 94%. Most (91%) would recommend a nerve block for post‐traumatic headaches.

Conclusion

The ease with which peripheral nerve blocks of the scalp can be performed combined with the immediate relief experienced by patients makes them a potential addition to the armamentarium of headache management strategies for children and adolescent with post‐traumatic headaches.
Stereotype Threat and Attributional Ambiguity for Trans Women
Authors: McKinnon Rachel
Published: March 2014

In this paper I discuss the interrelated topics of stereotype threat and attributional ambiguity as they relate to gender and gender identity. The former has become an emerging topic in feminist philosophy and has spawned a tremendous amount of research in social psychology and elsewhere. But the discussion, at least in how it connects to gender, is incomplete: the focus is only on cisgender women and their experiences. By considering trans women's experiences of stereotype threat and attributional ambiguity, we gain a deeper understanding of the phenomena and their problematic effects.1
Gel Casting of Free‐Shapeable Ceramic Membranes with Adjustable Pore Size for Ultra‐ and Microfiltration
Authors: Brandes Christoph , Treccani Laura , Kroll Stephen , Rezwan Kurosch
Published: April 2014

The growing demand of reliable high‐performance membrane materials for separation processes requires new simple, straightforward, environmental friendly, sustainable approaches for membrane fabrication. In this study, we present an environmentally friendly gel‐casting, one‐pot process based on ionotropic‐gelation for obtaining alumina membranes. A slurry of alumina particles and the biopolymer alginate, which acts in combination with calcium iodate like a resin, was gelled in a controllable temperature dependent manner. Alumina membranes are obtained by three different shaping routes (extrusion, free‐forming, casting). The suitability of extruded capillaries in a polymer‐ceramic hybrid state (green body) and after sintering (1150°C for 2 h) for potential application in micro‐ and ultrafiltration is evaluated by monitoring the chemical and mechanical stability, permeability and separation behavior. Varying the initial alumina particle size from 200 to 900 nm, membranes with a narrow pore size distribution, predictable and tunable average pore diameters from 70 up to 480 nm and a constant open porosity of ~40%, are obtained. The permeability behavior is tested with fluorescence labeled submicron‐ and nano‐particles. Our novel colloidal processing route represents a very versatile tool for designing and manufacturing ceramic membranes with complex shapes for micro‐ (>0.1 μm) and ultrafiltration (0.1–0.01 μm).
Temperature‐ and Frequency‐Dependent Properties of the 0.75Bi1/2Na1/2TiO3–0.25SrTiO3 Lead‐Free Incipient Piezoceramic
Authors: Acosta Matias , Jo Wook , Rödel Jürgen
Published: April 2014

The dielectric and electromechanical properties of 0.75Bi1/2Na1/2TiO3–0.25 SrTiO3 (25ST) as a function of temperature and frequency were studied. It is shown that the 25ST is a relaxor ferroelectric as evidenced by the temperature‐dependent dielectric relaxations with an incipient piezoelectricity featured by the presence of a reversible electric‐field‐induced phase transformation at room temperature. The transition occurs on a broad electric field strength range depending on field amplitude and frequency. It is also accompanied by a huge strain that is attributed to repetitive poling and depoling originating due to the reversibility of the phase transition. The 25ST makes an attractive lead‐free candidate for stack actuators as it presents a high normalized d33* of ~600 pm/V at a low electric field of 4 kV/mm for frequencies ranging from 0.1 up to 100 Hz.