bluuebunny/crossref_metadata_2025 huggingface dataset:
Seasonal Prediction of Killing-Frost Frequency in South-Central Canada during the Cool/Overwintering-Crop Growing Season
Authors: Wu Zhiwei , Lin Hai , Li Yun , Tang Youmin
Published: August 2012

Seasonal killing-frost frequency (KFF) during the cool/overwintering-crop growing season is important for the Canadian agricultural sector to prepare and respond to such extreme agrometeorological events. On the basis of observed daily surface air temperature across Canada for 1957–2007, this study found that more than 86% of the total killing-frost events occur in April–May and exhibit consistent variability over south-central Canada, the country’s major agricultural region. To quantify the KFF year-to-year variations, a simple index is defined as the mean KFF of the 187 temperature stations in south-central Canada. The KFF variability is basically dominated by two components: the decadal component with a peak periodicity around 11 yr and the interannual component of 2.5–3.8 yr. A statistical method called partial least squares (PLS) regression is utilized to uncover principal sea surface temperature (SST) modes in the winter preceding the KFF anomalies. It is found that most of the leading SST modes resemble patterns of El Niño–Southern Oscillation (ENSO) and/or the Pacific decadal oscillation (PDO). This indicates that ENSO and the PDO might be two dominant factors for the KFF variability. From a 41-yr training period (1957–97), a PLS seasonal prediction model is established, and 1-month-lead real-time forecasts are performed for the validation period of 1998–2007. A promising skill level is obtained. For the KFF variability, the prediction skill of the PLS model is comparable to or even better than the newly developed Canadian Seasonal to Interannual Prediction System (CanSIPS), which is a state-of-the-art global coupled dynamical system.
Measuring the medical school educational environment: Validating an approach from Saudi Arabia
Authors: Alshehri Sarah A , Alshehri Abdulrahman F , Erwin T Dary
Published: August 2012

Objective:

This study is an empirical analysis of the female students’ attitudes toward the medical educational environment and climate in the College of Medicine at King Khalid University.

Setting:

The Dundee Ready Educational Environment Measure (DREEM) questionnaire was administered on the same day to 100 female students studying in the third (pre-clinical), fifth and sixth (final) year at the College of Medicine, King Khalid University. Although the sample size was limited in size, it was deemed acceptable for research purposes.

Method:

The study is conducted using the DREEM questionnaire. This study is different from other studies regarding testing hypothesis and advanced statistical analysis. A set of hypotheses were placed and examined using statistical techniques.

Results:

In general, we find that the total mean score was 112.95 out of a 200 maximum, the ideal educational environment as measured by this scale. All the hypotheses set were rejected and there was no difference in the results according to year of study such as the difference found in some previous studies. It was found that there are no statistically significant differences in the mean scores according to the year of study.

Conclusion:

This study follows a long literature of studies in different universities around the world using the DREEM scale. The limitations of previous studies were considered carefully and were used to provide a framework for this work. These results spotlight the need to improve the medical educational environment in Saudi universities in general. This study has highlighted some areas where further research and analysis is recommended.
Field supervision in countries ridden by armed conflict
Authors: Baum Nehami
Published: August 2012

This article considers some of the impacts of armed political conflicts on field supervision where supervisor and student are affiliated with different sides, as exemplified by the Jewish supervisor/Arab student dyad in social work training in Israel. This conflict, it suggests, impedes the development of a trusting supervisory bond, makes it difficult for supervisors to provide candid feedback and evaluation, and impairs the students’ development of professional identity. The article ends with detailed recommendations for dealing with the many practical issues that arise in field supervision in the context of armed conflicts.
Under the radar: Impact of policies of localism on substance misuse services for refugee and asylum seeking communities
Authors: Mills Karen
Published: August 2012

Drug services struggle to respond to the UK’s minority communities. Despite some success, suspicion persists. The UK government has advanced localism as a mechanism for supporting communities in developing systems which will meet their needs. Drawing upon three research projects, this article examines the needs of asylum seekers and refugees, the formation of communities and the barriers which leave individuals unnoticed. It explores the potential of localism to engage and support drug users in new communities.
Asylum seeker young people: Social work value conflicts in negotiating age assessment in the UK
Authors: Cemlyn Sarah Judith , Nye Miriam
Published: August 2012

This article examines social work with separated young asylum seekers following armed conflict, and focuses on ethical issues arising from contradictions between core social work values and immigration control. It considers problems facing these young people and policy responses internationally, in Europe and the UK. The tension between child welfare and immigration control permeates these responses, with the latter usually trumping the former. Age assessment is a particularly contentious issue involving UK social workers. Drawing on findings from a study of age assessment practice, the study concludes with the centrality of maintaining social work values and links with wider campaigning.
The power of sweet words: Local forms of intervention with war-affected women in rural Sierra Leone
Authors: Doucet Denise , Denov Myriam
Published: August 2012

During Sierra Leone’s civil war, women and girls experienced numerous forms of gender-based violence and gross human rights violations, which had profound implications both during and following the conflict. In the war’s aftermath, Sierra Leonean social workers provided crucial forms of support to war-affected women and girls. Drawing on in-depth interviews, this article explores local forms of social work assistance provided to women in the post-conflict period. The article examines the assistance provided, the techniques and approaches of local practitioners, and the perceived impact of the interventions. In examining these post-war interventions, we highlight the unique local approaches to practice, and their implications for international social work practice and research.
Modeling of one-dimensional thermal response of silica-phenolic composites with volume ablation
Authors: Shi Shengbo , Liang Jun , Yi Fajun , Fang Guodong
Published: August 2012

The silica-phenolic composites experience volume ablation when exposed to a radiant heat flux. Based on the analysis of mechanisms during volume ablation, a mathematical model was developed to predict the one-dimensional thermal response of the ablative material in this paper. After discretizing the space and time domain, the governing equations were described using the implicit finite differential form. Both the heat-mass transfer process and the moving boundary caused by thermal expansion, as well as the variation of pore pressure due to concentration and flow of the decomposition gases were considered in the formulation of the model. The thermal response of silica-phenolic composites during the volume ablation, including temperature distribution, pore pressure distribution, volume fraction of the phase components and degree of decomposition, were calculated by the proposed model. The time-dependent temperature progressions at different material depths were measured using a solar radiation heating experiment platform. The experimental and calculated temperature profiles are in good agreement.
NanoWear of Salivary Films vs. Substratum Wettability
Authors: Sotres J. , Pettersson T. , Lindh L. , Arnebrant T.
Published: August 2012

The pellicle serves as a multifunctional protective layer, providing, e.g., lubrication and remineralization and also acting as a diffusion barrier. In addition, since the formation of the pellicle precedes the adhesion of micro-organisms, it is also important as a conditioning film. We present a novel approach to study the influence of the water wettability of solid surfaces on the strength of adsorbed salivary films. It is based on studying the wear resistance of the films with an atomic force microscope operated in the friction force spectroscopy mode. This methodology provides the strength of the films in terms of the forces needed for breaking and removing them. Our results indicate that these forces are highly dependent on the water wettability of the underlying substrata, decreasing with increasing hydrophobicity. Thus, this study provides valuable information for the design of materials exposed in the oral cavity, i.e., materials that will minimize plaque formation and be easy to clean.
Componential Model of Reading (CMR)
Authors: Joshi R. Malatesha , Aaron P. G.
Published: August 2012

The three current models of identifying learning disabilities: discrepancy model, RtI, and Componential Model of reading are discussed in terms of their utility.
Social Capital and Networks in Film and TV: Jobs for the Boys?
Authors: Grugulis Irena , Stoyanova Dimitrinka
Published: August 2012

Social capital has been hailed as a means of virtuous, effective and enjoyable productivity through which firms can flourish. But it also confines advantage to network members and discriminates against non-members. This paper, drawing on detailed qualitative research into work in the UK film and TV industry, reveals the advantages and the disadvantages of social capital. Social capital aided recruitment, policed quality standards and ensured behavioural norms with the sort of speed and flexibility it would be hard to identify in other forms of organizing. However, it also advantaged white, middle-class men and ensured that middle-class signals came to be proxies for the most sought-after jobs. Professionals who were women, members of ethnic minorities or working class were less likely to secure jobs and were often restricted in the type of jobs they held. Significantly, the members of disadvantaged groups who succeeded did so after long periods employed by the terrestrial broadcasters or after extended apprenticeships. This is worrying, given the increasing insecurity of the labour market in this sector.
Work Values, Early Career Difficulties, and the U.S. Economic Recession
Authors: Johnson Monica Kirkpatrick , Sage Rayna Amber , Mortimer Jeylan T.
Published: August 2012

We examine how work difficulties in the early career and the generally deteriorating work conditions associated with the recent U.S. economic recession shape individuals’ work values. Drawing on panel data from the Youth Development Study, we test whether individuals change their work values in response to concerns about satisfying material needs or the features of jobs that they are able to attain. Results indicate that extrinsic values are weakened in the face of unemployment, as well as reduced job security, income, and advancement. These patterns support a reinforcement and accentuation model in which workers adjust their values to emphasize what they actually obtain from the job. Intrinsic values are weakened by working in a job unrelated to one’s career plans; they are reinforced by the experience of greater intrinsic rewards and advancement opportunities.
A New Strategy for Dealing With Social Loafers on the Group Project
Authors: Dommeyer Curt J.
Published: August 2012

Professors often give members of a group project the same grade or they use peer evaluations to provide individualized grades. Unfortunately, both these methods have shortcomings. This article describes the segment manager method (SMM), a method for assigning individualized grades on the group project that does not rely on peer evaluations. A quasi-experiment is described where marketing research students are graded in groups either with peer evaluations (the control group) or with the SMM (the treatment group). Students participating in the quasi-experiment were more likely to prefer the SMM over the approach that uses peer evaluations. Moreover, when the SMM is compared with the peer evaluations approach, the SMM appears to be more likely to generate individualized grades on the group project that reflect each student’s academic ability, to deter social loafing, to increase scores on the group project, and to increase scores on an exam that is heavily loaded with project material. Recommendations for future users of the SMM are offered.
Migraine, weight gain and the risk of becoming overweight and obese: A prospective cohort study
Authors: Winter Anke C , Wang Lu , Buring Julie E , Sesso Howard D , Kurth Tobias
Published: August 2012

Background:

Some cross-sectional studies have suggested an association between migraine and increased body weight. However, prospective data on the association are lacking.

Methods:

We conducted a prospective cohort study among 19,162 participants in the Women’s Health Study who had a body mass index (BMI) of 18.5– <25 kg/m2 at baseline. Migraine was self-reported by standardized questionnaires. Main outcome measures were incident overweight (BMI ≥ 25 kg/m2), incident obesity (BMI ≥ 30 kg/m2) and mean weight change. Age- and multivariable-adjusted hazard ratios (HRs) were calculated for the association between migraine and incident overweight and obesity. Differences in weight change were evaluated by analysis of covariance (ANCOVA).

Results:

A total of 3,483 (18.2%) women reported any migraine history. After 12.9 years of follow-up, 7916 incident overweight and 730 incident obesity cases occurred. Migraineurs had multivariable-adjusted HRs (95% confidence interval) of 1.11 (1.05–1.17) for becoming overweight and 1.00 (0.83–1.19) for becoming obese. These associations remained stable after censoring for chronic diseases and were similar according to migraine aura status. Multivariable-adjusted mean weight change from baseline to the end of study was +4.7 kg for migraineurs and +4.4 kg for women without migraine ( p = 0.02).

Conclusion:

Results of this large prospective study of middle-aged women do not indicate a consistent association between migraine and incident overweight, obesity or relevant weight gain.
A modified imperialist competitive algorithm for constrained optimization of plate-fin heat exchangers
Authors: Yousefi Moslem , Yousefi Milad , Darus Amer Nordin
Published: August 2012

In this study, to handle the design optimization of plate-fin heat exchangers, a constrained version of a newly introduced evolutionary algorithm, the imperialist competitive algorithm, is proposed. Imperialist competitive algorithm was initially established for unconstrained optimization problems and different strategies such as penalty functions were employed to handle the constraints in the previous studies. In the proposed constrained imperialist competitive algorithm, a feasibility-based ranking is employed in the imperialist competitive algorithm method. Seven design parameters and various constraints are considered for the design optimization in which minimum weight and minimum total annual cost were considered as the autonomous objective functions. The results are compared with those obtained by a genetic algorithm approach combined with a static penalty function scheme. Also, a comparison between the proposed algorithm and the original imperialist competitive algorithm is performed. The simulation results show that both the proposed algorithm and imperialist competitive algorithm are of higher accuracy than the genetic algorithm, which is commonly used. Also, the numerical experiment indicates that the modification in the imperialist competitive algorithm leads to better performance of the algorithm.
CD4+CD25+High Foxp3+ Regulatory T Cells, B Lymphocytes, and T Lymphocytes in Patients With Acute ITP in Assiut Children Hospital
Authors: Zahran Asmaa M. , Elsayh Khalid I.
Published: August 2012

We aimed to examine the levels of lymphocyte subsets and regulatory T cells in patients with newly diagnosed immune thrombocytopenia (ITP) and their correlation with the course of ITP. The study included 40 pediatric patients with acute ITP and 30 controls. Lymphocytes and regulatory T cells were analyzed by flow cytometry. The percentages of CD19+ and CD8+ cells were significantly increased while that of CD4+ cells and CD4+/CD8+ ratio were significantly decreased. The percentages of CD4+CD25+High and CD4+CD25+High forkhead box protein 3 (Foxp3+) cells and the expression of Foxp3+ in CD4+CD25+High cells were significantly decreased in patients. Age, platelet count, and mean platelet volume (MPV) in patients with brief duration of thrombocytopenia were significantly decreased than in those with prolonged duration. The percentages of CD8+, CD4+CD25+High, and CD4+CD25+High Foxp3+ were significantly increased in patients with brief duration. Age, platelet count and MPV, and CD8+ cells had prognostic significance. CD4+CD25+High Foxp+ T cells may be a helpful prognostic marker in children with acute ITP.
Writing Instruction for Students With Autism Spectrum Disorders
Authors: Pennington Robert C. , Delano Monica E.
Published: August 2012

Historically, learners with autism spectrum disorders (ASD) have not had access to the general education curriculum. Current legislation mandates that all children, including children with ASD, have access to and make progress in the general education curriculum. This article contains a review of the literature on writing instruction for children with ASD. Investigation yielded 15 studies with 29 participants with ASD ages 4 to 21 years. Based on the studies reviewed, we concluded that students with ASD benefit from explicit writing instruction, but more research is needed to establish an evidence-based set of practices to guide educators in the development of effective writing programs for this population of students. Strategies that are particularly promising and suggestions for future research are given.
Techniques of Bronchial Sleeve Resection
Authors: Yu Jessica A. , Weyant Michael J.
Published: August 2012

A bronchial sleeve resection can be considered for lesions arising from a lobar bronchus so as to preclude a standard lobectomy, yet without enough distal involvement as to warrant a pneumonectomy. Limited bronchial resection allows maximal conservation of pulmonary function in patients with benign or malignant disease, without compromising oncologic outcome. This article defines the indications and preoperative management of candidate patients and discusses key anesthetic considerations and surgical techniques for this complex airway reconstruction. The essential component of a successful operation is a tension-free bronchial anastomosis. Open communication and careful discussion of airway management between anesthesiologist and surgeon will help ensure a good outcome.
Minimal residual disease monitoring by quantitative RT-PCR in core binding factor AML allows risk stratification and predicts relapse: results of the United Kingdom MRC AML-15 trial
Authors: Yin John A. Liu , O'Brien Michelle A. , Hills Robert K. , Daly Sarah B. , Wheatley Keith , Burnett Alan K.
Published: August 2012

The clinical value of serial minimal residual disease (MRD) monitoring in core binding factor (CBF) acute myeloid leukemia (AML) by quantitative RT-PCR was prospectively assessed in 278 patients [163 with t(8;21) and 115 with inv(16)] entered in the United Kingdom MRC AML 15 trial. CBF transcripts were normalized to 105ABL copies. At remission, after course 1 induction chemotherapy, a > 3 log reduction in RUNX1-RUNX1T1 transcripts in BM in t(8;21) patients and a > 10 CBFB-MYH11 copy number in peripheral blood (PB) in inv(16) patients were the most useful prognostic variables for relapse risk on multivariate analysis. MRD levels after consolidation (course 3) were also informative. During follow-up, cut-off MRD thresholds in BM and PB associated with a 100% relapse rate were identified: for t(8;21) patients BM > 500 copies, PB > 100 copies; for inv(16) patients, BM > 50 copies and PB > 10 copies. Rising MRD levels on serial monitoring accurately predicted hematologic relapse. During follow-up, PB sampling was equally informative as BM for MRD detection. We conclude that MRD monitoring by quantitative RT-PCR at specific time points in CBF AML allows identification of patients at high risk of relapse and could now be incorporated in clinical trials to evaluate the role of risk directed/preemptive therapy.
Different metastatic pattern according to the KRAS mutational status and site-specific discordance of KRAS status in patients with colorectal cancer
Authors: Kim Mi-Jung , Lee Hye Seung , Kim Jee Hyun , Kim Yu Jung , Kwon Ji Hyun , Lee Jeong-Ok , Bang Soo-Mee , Park Kyoung Un , Kim Duck-Woo , Kang Sung-Bum , Kim Jae-Sung , Lee Jong Seok , Lee Keun-Wook
Published: August 2012

Background

We evaluated the association between a KRAS mutational status and various clinicopathologic features including the metastatic pattern in patients with metastatic or recurrent colorectal cancer (MRCRC). The concordance rates of the KRAS status between primary tumor sites and paired metastatic organs were also analyzed.

Methods

The KRAS mutational status in codons 12, 13, and 61 from formalin-fixed sections of both primary tumors and related metastases was determined by sequencing analysis. One hundred forty-three Korean patients with MRCRC with available tissues (resection or biopsy) from both primary tumors and related metastatic sites were consecutively enrolled.

Results

The KRAS mutation rate was 52.4% (75/143) when considering both the primary and metastatic sites. When the relationship between the KRAS status and initial metastatic sites at the time of diagnosis of MRCRC was analyzed, lung metastasis was more frequent as the initial metastatic site in patients with the KRAS mutation than in patients without the KRAS mutation (45.3% vs. 22.1%; P = 0.003). However, liver (37.3% vs. 70.6%; P < 0.001) or distant lymph node metastases (6.7% vs. 19.1%; P = 0.025) were less frequent as the initial metastatic organ in patients with the KRAS mutation than in patients without the KRAS mutation. The discordance rate of KRAS mutational status between primary and paired metastatic sites other than the lung was 12.3% (13/106). Compared with primary tumor sites, the KRAS discordance rate was significantly higher in matched lung metastases [32.4% (12/37)] than in other matched metastatic organs (P = 0.005).

Conclusions

Organs initially involved by distant metastasis were different according to the KRAS mutational status in MRCRC patients. The concordance rate (87.7%) of the KRAS mutation status at metastatic sites other than the lung was generally high compared with primary tumor sites; however, lung metastasis had a high rate of KRAS discordance (32.4%).
Quality of health news disseminated in the print media in developing countries: a case study in Iran
Authors: Ashoorkhani Mahnaz , Gholami Jaleh , Maleki Katayoun , Nedjat Sima , Mortazavi Jalaledin , Majdzadeh Reza
Published: August 2012

Background

Mass media play an important role in keeping people up-to-date with the latest health news. This study aims at investigating the quality of health news disseminated in the print media, its course of production and factors affecting its quality.

Methods

In the quantitative section of the study, 410 health-related news items, published during a six-month span in the Iranian public press, underwent content analysis. In the qualitative section, focus group discussions were held with journalists, editors-in-chief and news gatekeepers.

Results

The quantitative phase showed that 18% of the news articles were not fit for dissemination in public. The qualitative phase illustrated that multiple factors at various levels affect the quality of news, namely poor knowledge, inadequate motivations and context-related barriers.

Conclusions

The quality of health news reporting is not desirable. Educational interventions need to be carried out to raise awareness among researchers and journalists. Also, certain steps should be taken to increase motivations and strengthen infrastructures, including designing guidelines and monitoring news.
An exploration of the role of pharmacists within general practice clinics: the protocol for the pharmacists in practice study (PIPS)
Authors: Tan Edwin , Stewart Kay , Elliott Rohan A , George Johnson
Published: August 2012

Background

Medication-related problems are a serious concern in Australian primary care. Pharmacist interventions have been shown to be effective in identifying and resolving these problems. Collaborative general practitioner-pharmacist services currently available in Australia are limited and underused. Limitations include geographical isolation of pharmacists and lack of communication and access to patient information. Co-location of pharmacists within the general practice clinics is a possible solution. There have been no studies in the Australian setting exploring the role of pharmacists within general practice clinics.

The aim of this study is to develop and test a multifaceted practice pharmacist role in primary care practices to improve the quality use of medicines by patients and clinic staff.

Methods/design

This is a multi-centre, prospective intervention study with a pre-post design and a qualitative component. A practice pharmacist will be located in each of two clinics and provide short and long patient consultations, drug information services and quality assurance activities. Patients receiving long consultation with a pharmacist will be followed up at 3 and 6 months. Based on sample size calculations, at least 50 patients will be recruited for long patient consultations across both sites. Outcome measures include the number, type and severity of medication-related problems identified and resolved; medication adherence; and patient satisfaction. Brief structured interviews will be conducted with patients participating in the study to evaluate their experiences with the service. Staff collaboration and satisfaction with the service will be assessed.

Discussion

This intervention has the potential to optimise medication use in primary care clinics leading to better health outcomes. This study will provide data about the effectiveness of the proposed model for pharmacist involvement in Australian general practice clinics, that will be useful to guide further research and development in this area.

Trial registration

Australian New Zealand Clinical Trials Registry: ACTRN12612000742875
Steroid biotransformations in biphasic systems with Yarrowia lipolytica expressing human liver cytochrome P450 genes
Authors: Braun Andreas , Geier Martina , Bühler Bruno , Schmid Andreas , Mauersberger Stephan , Glieder Anton
Published: August 2012

Background

Yarrowia lipolytica efficiently metabolizes and assimilates hydrophobic compounds such as n-alkanes and fatty acids. Efficient substrate uptake is enabled by naturally secreted emulsifiers and a modified cell surface hydrophobicity and protrusions formed by this yeast. We were examining the potential of recombinant Y. lipolytica as a biocatalyst for the oxidation of hardly soluble hydrophobic steroids. Furthermore, two-liquid biphasic culture systems were evaluated to increase substrate availability. While cells, together with water soluble nutrients, are maintained in the aqueous phase, substrates and most of the products are contained in a second water-immiscible organic solvent phase.

Results

For the first time we have co-expressed the human cytochromes P450 2D6 and 3A4 genes in Y. lipolytica together with human cytochrome P450 reductase (hCPR) or Y. lipolytica cytochrome P450 reductase (YlCPR). These whole-cell biocatalysts were used for the conversion of poorly soluble steroids in biphasic systems.

Employing a biphasic system with the organic solvent and Y. lipolytica carbon source ethyl oleate for the whole-cell bioconversion of progesterone, the initial specific hydroxylation rate in a 1.5 L stirred tank bioreactor was further increased 2-fold. Furthermore, the product formation was significantly prolonged as compared to the aqueous system.

Co-expression of the human CPR gene led to a 4-10-fold higher specific activity, compared to the co-overexpression of the native Y. lipolytica CPR gene. Multicopy transformants showed a 50-70-fold increase of activity as compared to single copy strains.

Conclusions

Alkane-assimilating yeast Y. lipolytica, coupled with the described expression strategies, demonstrated its high potential for biotransformations of hydrophobic substrates in two-liquid biphasic systems. Especially organic solvents which can be efficiently taken up and/or metabolized by the cell might enable more efficient bioconversion as compared to aqueous systems and even enable simple, continuous or at least high yield long time processes.
Low-level HIV infection of hepatocytes
Authors: Kong Ling , Maya Walter Cardona , Moreno-Fernandez Maria E , Ma Gang , Shata Mohamed T , Sherman Kenneth E , Chougnet Claire , Blackard Jason T
Published: August 2012

Background

There are only limited data on whether HIV infection occurs within the liver; therefore, we explored early and late stages of the HIV life cycle in two hepatocyte cell lines – Huh7.5 and Huh7.5JFH1 – as well as in primary human hepatocytes.

Results

Integrated HIV DNA was detected in Huh7.5 and Huh7.5JFH1 cells, as well as in primary hepatocytes, and was inhibited by the integrase inhibitor raltegravir in a dose-dependent manner. HIV p24 protein was also detected in cell culture supernatants at days 1, 3, 5, and 7 post-infection and was inhibited by AZT, although levels were modest compared to those in a lymphocyte cell line. Culture supernatants from HIV-infected hepatocytes were capable of infecting a non-hepatic HIV indicator cell line.

Conclusions

These results indicating low-level HIV replication in hepatoctyes in vitro complement evidence suggesting that HIV has deleterious effects on the liver in vivo.
Cervical spinal cord bullet fragment removal using a minimally invasive surgical approach: a case report
Authors: Lawton Cort D , Smith Zachary A , Sugimoto Koichi , Smith Justin S , Fessler Richard G
Published: August 2012

Introduction

We present a case of penetrating gunshot injury to the high-cervical spinal cord and describe a minimally invasive approach used for removal of the bullet fragment. We present this report to demonstrate technical feasibility of a minimally invasive approach to projectile removal.

Case presentation

An 18-year-old African-American man presented to our hospital with a penetrating gunshot injury to the high-cervical spine. The bullet lodged in the spinal cord at the C1 level and rendered our patient quadriplegic and dependent on a ventilator. For personal and forensic reasons, our patient and his family requested removal of the bullet fragment almost one year following the injury. Given the significant comorbidity associated with quadriplegia and ventilator dependency, a minimally invasive approach was used to limit the peri-operative complication risk and expedite recovery. Using a minimally invasive expandable retractor system and the aid of a microscope, the posterior arch of C1 was removed, the dura was opened, and the bullet fragment was successfully removed from the spinal cord.

Conclusions

Here we describe a minimally invasive procedure demonstrating the technical feasibility of removing an intramedullary foreign object from the high-cervical spine. We do not suggest that the availability of minimally invasive procedures should lower the threshold or expand the indications for the removal of bullet fragments in the spinal canal. Rather, our objective is to expand the indications for minimally invasive procedures in an effort to reduce the morbidity and mortality associated with spinal procedures. In addition, this report may help to highlight the feasibility of this approach.
The immune theory of psychiatric diseases: a key role for activated microglia and circulating monocytes
Authors: Beumer Wouter , Gibney Sinead M , Drexhage Roosmarijn C , Pont-Lezica Lorena , Doorduin Janine , Klein Hans C , Steiner Johann , Connor Thomas J , Harkin Andrew , Versnel Marjan A , Drexhage Hemmo A
Published: August 2012

Review on the key role for activated microglia and monocytes in the pathogenesis of bipolar disorder and schizophrenia.

This review describes a key role for mononuclear phagocytes in the pathogenesis of major psychiatric disorders. There is accumulating evidence for activation of microglia (histopathology and PET scans) and circulating monocytes (enhanced gene expression of immune genes, an overproduction of monocyte/macrophage-related cytokines) in patients with bipolar disorder, major depressive disorder, and schizophrenia. These data are strengthened by observations in animal models, such as the MIA models, the chronic stress models, and the NOD mouse model. In these animal models of depressive-, anxiety-, and schizophrenia-like behavior, similar activations of microglia and circulating monocytes can be found. These animal models also make in-depth pathogenic studies possible and show that microglia activation impacts neuronal development and function in brain areas congruent with the altered depressive and schizophrenia-like behaviors.
On the instability in second-order systems for acoustic VTI and TTI media
Authors: Bube Kenneth P. , Nemeth Tamas , Stefani Joseph P. , Ergas Ray , Liu Wei , Nihei Kurt T. , Zhang Linbin
Published: August 2012

We studied second-order wave propagation systems for vertical transversely isotropic (VTI) and tilted transversely isotropic (TTI) acoustic media with variable axes of symmetry that have their shear-wave speeds set to zero. Acoustic TTI systems are commonly used in reverse-time migration, but these second-order systems are susceptible to instablities appearing as nonphysical stationary noise growing linearly in time, particularly in variable-tilt TTI media. We found an explanation of the cause of this phenomenon. The instabilities are not caused only by the numerical schemes; they are inherent to the differential equations. These instabilities are present even in homogeneous VTI media. These instabilities are caused by zero wave speeds at a wide variety of wavenumbers — a direct consequence of setting the shear-wave speeds to zero — coupled with the second time derivative in these systems. Although the second-order isotropic wave equation allows smooth time-growing solutions, a larger class of time-growing solutions exists for the second-order acoustic TI systems, including nonsmooth solutions. Boundary conditions appear to be less effective in controlling these time-growing solutions than they are for the isotropic wave equation. These systems conserve an incomplete energy that does not prevent the instabilities. The corresponding steady-state systems are no longer elliptic differential equations and can have nonsmooth solutions that are related to the instabilities. We started initially with homogeneous VTI media, and then extended these results to heterogeneous variable-tilt TTI media. We also developed a second-order acoustic system for heterogeneous variable-tilt TTI media derived directly from the full-elastic system for heterogeneous variable-tilt TTI media. All second-order systems with a dispersion relation obtained by setting the shear-wave speeds to zero in the elastic dispersion relation allowed these nonphysical time-growing solutions; however, knowing the cause of these instabilities, it may be possible to prevent or control the activation of these solutions.
Quasi-analytical method for frequency-to-time conversion in CSEM applications
Authors: Tehrani Ali Moradi , Slob Evert , Mulder Wim
Published: August 2012

Frequency-to-time transformations are of interest to controlled-source electromagnetic methods when time-domain data are inverted for a subsurface resistivity model by numerical frequency-domain modeling at a selected, small number of frequencies whereas the data misfit is determined in the time domain. We propose an efficient, Prony-type method using frequency-domain diffusive-field basis functions for which the time-domain equivalents are known. Diffusive fields are characterized by an exponential part whose argument is proportional to the square root of frequency and a part that is polynomial in integer powers of the square root of frequency. Data at a limited number of frequencies suffice for the transformation back to the time. In the exponential part, several diffusion-time values must be chosen. Once a suitable range of diffusion-time values are found, the method is quite robust in the number of values used. The highest power in the polynomial part can be determined from the source and receiver type. When the frequency-domain data are accurately approximated by the basis functions, the time-domain result is also accurate. This method is accurate over a wider time range than other methods and has the correct late-time asymptotic behavior. The method works well for data computed for layered and 3D subsurface models.
Croatian Foreign Policy in the Context of European Union Membership
Authors: Pusić Vesna
Published: August 2012

In this essay, Croatia’s minister of foreign and European affairs outlines Croatia’s foreign policy directions as a member of the European Union. Mutual benefits to the EU and Croatia of the latter’s membership are outlined, with particular reference to issues in southeastern Europe and with countries along the southern Mediterranean shoreline. The membership process itself is described as a driver in the development of Croatia’s foreign relations.
Spherical cell shape of FLC-4 cell, a human hepatoma cell, enhances hepatocyte-specific function and suppresses tumor phenotype through the integration of mRNA–microRNA interaction
Authors: Laurent Thomas , Kataoka Yutaro , Kobayashi Satoru , Ando Misaki , Nagamori Seishi , Oda Hiroaki
Published: August 2012

The induction mechanism of HNF-4α by spherical cell shape in human hepatoma cells, FLC-4, was investigated. To get insight into the induction mechanism of HNF-4α in three-dimensional FLC-4 cells, mRNA microarray analysis was performed. The gene expression related to drug metabolism and nuclear receptors, such as LXRα, was elevated in spherical FLC-4 cells. We found the first time that the expressions of genes related to malignancy of hepatoma cells, such as HIF-1α, c-Myc and VEGFC, were downregulated by spherical cell shape. Network analysis revealed that HNF-4α would elicit both the enhancement of hepatocyte-specific gene expression and suppression of malignancy. Since HNF-4α gene expression was known to be regulated by microRNA, we inferred that spherical cell shape would induce HNF-4α gene expression through microRNA. To investigate the possibility of such a mechanism, mRNA–microRNA interactions were examined using microRNA microarray and bioinformatics analysis. The level of miR-24, a microRNA targeting HNF-4α, was reduced in spherical FLC-4 cells. On the other hand, spherical cell shape-induced miR-194 and miR-320c would directly downregulate SLC7A5 and E2F1 gene expression, respectively, which are both related to malignancy. Our study suggested that spherical cell shape would induce HNF-4α gene expression and consequent enhancement hepatocyte-specific functions. Spherical cell shape itself would suppress malignancy in FLC-4 cells through microRNA, such as miR-194 and miR-320c.
Atonal and EGFR signalling orchestraterok- andDrak-dependent adherens junction remodelling during ommatidia morphogenesis
Authors: Robertson Francesca , Pinal Noelia , Fichelson Pierre , Pichaud Franck
Published: August 2012

Morphogenesis of epithelial tissues relies on the interplay between cell division, differentiation and regulated changes in cell shape, intercalation and sorting. These processes are often studied individually in relatively simple epithelia that lack the complexity found during organogenesis when these processes might all coexist simultaneously. To address this issue, we are making use of the developing fly retinal neuroepithelium. Retinal morphogenesis relies on a coordinated sequence of interdependent morphogenetic events that includes apical cell constriction, localized alignment of groups of cells and ommatidia morphogenesis coupled to neurogenesis. Here, we use live imaging to document the sequence of adherens junction (AJ) remodelling events required to generate the fly ommatidium. In this context, we demonstrate that the kinases Rok and Drak function redundantly during Myosin II-dependent cell constriction, subsequent multicellular alignment and AJ remodelling. In addition, we show that early multicellular patterning characterized by cell alignment is promoted by the conserved transcription factor Atonal (Ato). Further ommatidium patterning requires the epidermal growth factor receptor (EGFR) signalling pathway, which transcriptionally governs rok- and Drak-dependent AJ remodelling while also promoting neurogenesis. In conclusion, our work reveals an important role for Drak in regulating AJ remodelling during retinal morphogenesis. It also sheds new light on the interplay between Ato, EGFR-dependent transcription and AJ remodelling in a system in which neurogenesis is coupled with cell shape changes and regulated steps of cell intercalation.
Pten deletion causes mTorc1-dependent ectopic neuroblast differentiation without causing uniform migration defects
Authors: Zhu Guo , Chow Lionel M. L. , Bayazitov Ildar T. , Tong Yiai , Gilbertson Richard J. , Zakharenko Stanislav S. , Solecki David J. , Baker Suzanne J.
Published: August 2012

Neuronal precursors, generated throughout life in the subventricular zone, migrate through the rostral migratory stream to the olfactory bulb where they differentiate into interneurons. We found that the PI3K-Akt-mTorc1 pathway is selectively inactivated in migrating neuroblasts in the subventricular zone and rostral migratory stream, and activated when these cells reach the olfactory bulb. Postnatal deletion of Pten caused aberrant activation of the PI3K-Akt-mTorc1 pathway and an enlarged subventricular zone and rostral migratory stream. This expansion was caused by premature termination of migration and differentiation of neuroblasts and was rescued by inhibition of mTorc1. This phenotype is reminiscent of lamination defects caused by Pten deletion in developing brain that were previously described as defective migration. However, live imaging in acute slices showed that Pten deletion did not cause a uniform defect in the mechanics of directional neuroblast migration. Instead, a subpopulation of Pten-null neuroblasts showed minimal movement and altered morphology associated with differentiation, whereas the remainder showed unimpeded directional migration towards the olfactory bulb. Therefore, migration defects of Pten-null neurons might be secondary to ectopic differentiation.
Measurement of teicoplanin by liquid chromatography-tandem mass spectrometry: development of a novel method
Authors: Fung Francis H Y , Tang Jonathan C Y , Hopkins John P P , Dutton John J , Bailey Lisa M , Davison Andrew S
Published: August 2012

Background

Teicoplanin is an antibiotic used for the treatment of endocarditis, osteomyelitis, septic arthritis and methicillin-resistant Staphylococcus aureus. Teicoplanin is emerging as a suitable alternative antibiotic to vancomycin, where their trough serum levels are monitored by immunoassay routinely. This is the first report detailing the development of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for measuring teicoplanin in patients' serum.

Methods

An Acquity™ UPLC (ultra-pressure liquid chromatography) tandem mass spectrometer was used to measure teicoplanin concentrations in samples from patients, quality assurance schemes and quality control preparations. Ristocetin was successfully implemented as a suitable internal standard. Ion suppression, linearity, stability, matrix effects, recovery, imprecision, lower limits of quantification and detection, interference and method comparison against immunoassay were all assessed.

Results

Teicoplanin and ristocetin had elution times of 1.39 and 1.24 min, respectively. Ion suppression was shown to be negligible, and linear calibration curves (0–200 μg/mL) were consistently reproduced to have r2 values >0.99. Postextraction stability was achieved up to 20 h, while matrix effects were minimal coupled with sample recovery of >93%. The lower limit of quantification was 1 μg/mL, and 0.2 μg/mL was the lower limit of detection. Interference with other antibiotics was dependent on the combination of drugs present in patients’ serum. A method comparison between immunoassay and LC-MS/MS suggested a negative bias for tandem mass spectrometry.

Conclusions

This novel method of teicoplanin determination by LC-MS/MS is proven to be a robust protocol that is consistent and reproducible. Clinicians searching for alternatives in therapeutic drug monitoring may have an additional option that is potentially more accurate and specific.
Norisoboldine, an alkaloid compound isolated from Radix Linderae, inhibits synovial angiogenesis in adjuvant-induced arthritis rats by moderating Notch1 pathway-related endothelial tip cell phenotype
Authors: Lu Qian , Lu Shuai , Gao Xinghua , Luo Yubin , Tong Bei , Wei Zhifeng , Lu Tao , Xia Yufeng , Chou Guixin , Wang Zhengtao , Dai Yue
Published: August 2012

Synovial angiogenesis is well recognized as participating in the pathogenesis of rheumatoid arthritis (RA) and has been regarded as a potential target for RA therapy. Previously, we have shown that norisoboldine (NOR) can protect joints from destruction in mice with collagen II-induced arthritis (CIA). Here, we investigate the effect of NOR on synovial angiogenesis in adjuvant-induced arthritis (AA) rats, and clarify the mechanisms in vitro. NOR, administered orally, significantly reduced the number of blood vessels and expression of growth factors in the synovium of AA rats. In vitro, it markedly prevented the migration and sprouting of endothelial cells . Notably, the endothelial tip cell phenotype, which is essential for the migration of endothelial cells and subsequent angiogenesis, was significantly inhibited by NOR. This inhibitory effect was attenuated by pretreatment with N-{ N-[2-(3,5-difluorophenyl) acetyl]-( S)-alanyl}-( S)-phenylglycine tert-butyl ester, a Notch1 inhibitor, suggesting that the action of NOR was related to the Notch1 pathway. A molecular docking study further confirmed that NOR was able to promote Notch1 activation by binding the Notch1 transcription complex. In conclusion, NOR was able to prevent synovial angiogenesis in AA rats, which is a putatively new mechanism responsible for its anti-rheumatoid effect. The anti-angiogenesis action of NOR was likely achieved by moderating the Notch1 pathway-related endothelial tip cell phenotype with a potential action target of the Notch1 transcription complex.