bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of testosterone on cardiomyocyte calcium homeostasis and contractile function in female rats
Authors: Beesley Ronald D. , Palmer Bradley M. , Casson Peter R. , Toth Michael J.
Published: July 2012

New Findings

What is the central question of this study?

Androgen excess in women is associated with an elevated risk for heart disease. Whether some portion of this elevated risk is related to an effect of androgens on cariomyoctye function, however, has not been examined. To our knowledge, this is the first study to directly address the role of androgens in regulating cardiomyocyte contractile dynamics and calcium homeostasis.

What is the main finding and its importance?

Our results suggest minimal acute or chronic effects of testosterone on cardiomyocyte shortening dynamics, calcium homeostasis or myosin heavy chain expression, suggesting that the detrimental effect of androgen excess on cardiovascular risk is not mediated through alterations in cardiomyocyte biology.

The role of testosterone (T) in the regulation of cardiovascular function in females is not well understood. Our goal was to examine the effect of T on cardiomyocyte biology by measuring sarcomere shortening/relaxation and intracellular calcium cycling in adult female Sprague–Dawley rats. The rats were divided into the following four groups: (1) sham operated; (2) ovariectomized (OVX); (3) OVX plus T; and (4) OVX + T plus an aromatase inhibitor (AI). The final group was added to rule out effects from bioconversion of T to oestradiol. Sarcomere/calcium dynamics were measured after 4 weeks at 2 and 6 Hz, then at 6 Hz following exposure to 300 nm isoprenaline. Additionally, the acute (i.e. non‐genomic) effects of T were evaluated in sham‐operated and OVX + T + AI rats. There were no group differences, nor was there evidence for an effect of T on frequency or isoprenaline response. Additionally, there were no findings to indicate an acute, non‐genomic T effect. Moreover, the relative α‐ and β‐myosin heavy chain isoform complement was unchanged by OVX or T replacement. Our results argue against acute or chronic effects of T on cardiomyocyte shortening dynamics, calcium cycling or myosin heavy chain expression, arguing against any direct effect of T on cardiomyocyte function in adult females.
Does ‘altitude training’ increase exercise performance in elite athletes?
Authors: Lundby Carsten , Millet Gregoire P , Calbet Jose A , Bärtsch Peter , Subudhi Andrew W
Published: July 2012

The general practice of altitude training is widely accepted as a means to enhance sport performance despite a lack of rigorous scientific studies. For example, the scientific gold-standard design of a double-blind, placebo-controlled, cross-over trial has never been conducted on altitude training. Given that few studies have utilised appropriate controls, there should be more scepticism concerning the effects of altitude training methodologies. In this brief review we aim to point out weaknesses in theories and methodologies of the various altitude training paradigms and to highlight the few well-designed studies to give athletes, coaches and sports medicine professionals the current scientific state of knowledge on common forms of altitude training. Another aim is to encourage investigators to design well-controlled studies that will enhance our understanding of the mechanisms and potential benefits of altitude training.
Mapping cardiac surface mechanics with structured light imaging
Authors: Laughner Jacob I. , Zhang Song , Li Hao , Shao Connie C. , Efimov Igor R.
Published: July 2012

Cardiovascular disease often manifests as a combination of pathological electrical and structural heart remodeling. The relationship between mechanics and electrophysiology is crucial to our understanding of mechanisms of cardiac arrhythmias and the treatment of cardiac disease. While several technologies exist for describing whole heart electrophysiology, studies of cardiac mechanics are often limited to rhythmic patterns or small sections of tissue. Here, we present a comprehensive system based on ultrafast three-dimensional (3-D) structured light imaging to map surface dynamics of whole heart cardiac motion. Additionally, we introduce a novel nonrigid motion-tracking algorithm based on an isometry-maximizing optimization framework that forms correspondences between consecutive 3-D frames without the use of any fiducial markers. By combining our 3-D imaging system with nonrigid surface registration, we are able to measure cardiac surface mechanics at unprecedented spatial and temporal resolution. In conclusion, we demonstrate accurate cardiac deformation at over 200,000 surface points of a rabbit heart recorded at 200 frames/s and validate our results on highly contrasting heart motions during normal sinus rhythm, ventricular pacing, and ventricular fibrillation.
LED Light-Activated Hypocrellin B Induces Mitochondrial Damage of Ovarian Cancer Cells
Authors: Jiang Yuan , Leung Albert Wingnang , Xiang Junyan , Xu Chuanshan
Published: July 2012

Objective. Hypocrellin is a natural photosensitizer from a traditional Chinese herb. In the present study, our aim is to investigate the effect of LED light-activated hypocrellin B on mitochondria of ovarian cancer cells.Material and Methods. Ovarian cancer HO-8910 cells were incubated with hypocrellin B at the concentration of 2.5 μM for 5 h and then irradiated by blue light from a novel LED source. Cell survival rate of HO-8910 cells was measured using MTT assay 24 h after photodynamic treatment of hypocrellin B. Mitochondrial morphology was observed using transmission electron microscopy (TEM). Mitochondrial membrane potential was measured using flow cytometry with JC-1 staining.Results. MTT assay showed that cell survival rate of HO-8910 cells in the photodynamic treatment group has significantly decreased down to27.22±1.26% (P<0.01). Light irradiation alone or hypocrellin B alone showed no significant impact. In our TEM mitochondria of the cells after photodynamic treatment of hypocrellin B showed severe damage with swollen mitochondria that had nearly nonexistant cristae. Mitochondrial membrane potential remarkably decreased after photodynamic action of hypocrellin B.Conclusion. The findings demonstrated that photodynamic action of hypocrellin B significantly decreased cell proliferation of ovarian cancer HO-8910 cells, caused severe damage to mitochondrial structure, and induced mitochondrial membrane collapse.
The Effect of Amifostine on Submandibular Gland Histology after Radiation
Authors: Junn Jacqueline C. , Sciubba James J. , Bishop Justin A. , Zinreich Eva , Tang Mei , Levine Marshall A. , Palermo Robert A. , Fakhry Carole , Blanco Ray G. , Saunders John R. , Califano Joseph A. , Ha Patrick K.
Published: July 2012

Background. The purpose of this study was to assess the effects of amifostine on submandibular gland histology in patients receiving chemoradiation therapy.Methods.We conducted a retrospective submandibular gland histologic slide review of HNSCC patients receiving chemoradiation for head and neck squamous cell carcinoma with three different levels of amifostine exposure. We used six scoring parameters: fatty replacement, lobular architecture degeneration, interstitial fibrosis, ductal degeneration, acinar degeneration, and inflammatory component presence.Results. Differences in gender, tumor stage, amifostine dose, age, number of days after neck dissection, and smoking history (pack years) exposure were not significant between the three groups, although there was a difference between groups in the primary subsite (P=0.006). The nonparametric Cuzick's test for histologic parameters with varied amifostine treatment showed no significance among the three groups.Conclusions. Although patients did not receive a full dose of amifostine due to side effects, varying doses of amifostine had no apparent evident cytoprotective effects in three groups of cancer patients treated with primary chemoradiation.
Design of Microcantilever-Based Biosensor with Digital Feedback Control Circuit
Authors: Kalambe Jayu P. , Patrikar Rajendra M.
Published: July 2012

This paper present the design of cantilever-based biosensors with new readout, which hold promises as fast and cheap “point of care” device as well as interesting research tools. The fabrication process and related issues of the cantilever based bio-sensor are discussed. Coventorware simulation is carried out to analyze the device behavior. A fully integrated control circuit has been designed to solve manufacturing challenge which will take care of positioning of the cantilever instead of creating nanometer gap between the electrodes. The control circuit will solve the manufacturing challenge faced by the readout methods where it is essential to maintain precise gap between the electrodes. The circuit can take care of variation obtained due to fabrication process and maintain the precise gap between the electrodes by electrostatic actuation. The control circuit consist of analog and digital modules. The reliability issues of the sensor are also discussed.
Hydrogen Photoproduction byRhodopseudomonas palustris42OL Cultured at High Irradiance under a Semicontinuous Regime
Authors: Carlozzi Pietro
Published: July 2012

The main goal of this study was to increase the hydrogen production rate improving the culture technique and the photobioreactor performances. Experiments were carried out at a constant culture temperature of 30°C and at an average irradiance of 480 W m−2using a cylindrical photobioreactor (4.0 cm, internal diameter). The culture technique, namely, the semicontinuous regime for growingRhodopseudomonas palustris42OL made it possible to achieve a very high daily hydrogen production rate of 594 ± 61 mL (H2) L−1 d−1. This value, never reported for this strain, corresponds to about 25 mL (H2) L−1 h−1, and it was obtained when the hydraulic retention time (HRT) was of 225 hours. Under the same growth conditions, a very high biomass production rate (496 ± 45 mg (dw) L−1 d−1) was also achieved. Higher or lower HRTs caused a reduction in both the hydrogen and the biomass production rates. The malic-acid removal efficiency (MAre) was always higher than 90%. The maximal hydrogen yield was 3.03 mol H2mol MA−1at the HRT of 360 hours. The highest total energy conversion efficiency was achieved at the HRT of 225 hours.
Multiple Positive Solutions for a Fractional Boundary Value Problem with Fractional Integral Deviating Argument
Authors: Guezane-Lakoud A. , Khaldi R.
Published: July 2012

This work is devoted to the existence of positive solutions for a fractional boundary value problem with fractional integral deviating argument. The proofs of the main results are based on Guo-Krasnoselskii fixed point theorem and Avery and Peterson fixed point theorem. Two examples are given to illustrate the obtained results, ending the paper.
The Stability of Nonlinear Differential Systems with Random Parameters
Authors: Diblík Josef , Dzhalladova Irada , Růžičková Miroslava
Published: July 2012

The paper deals with nonlinear differential systems with random parameters in a general form. A new method for construction of the Lyapunov functions is proposed and is used to obtain sufficient conditions for L2‐stability of the trivial solution of the considered systems.
BAC-Dkk3-EGFPTransgenic Mouse: AnIn VivoAnalytical Tool forDkk3Expression
Authors: Muranishi Yuki , Furukawa Takahisa
Published: July 2012

Dickkopf (DKK) family proteins are secreted modulators of the Wnt signaling pathway and are capable of regulating the development of many organs and tissues. We previously identifiedDkk3to be a molecule predominantly expressed in the mouse embryonic retina. However, which cell expressesDkk3in the developing and mature mouse retina remains to be elucidated. To examine the precise expression of theDkk3protein, we generatedBAC-Dkk3-EGFPtransgenic mice that express EGFP integrated into theDkk3gene in a BAC plasmid. Expression analysis using theBAC-Dkk3-EGFPtransgenic mice revealed thatDkk3is expressed in retinal progenitor cells (RPCs) at embryonic stages and in Müller glial cells in the adult retina. Since Müller glial cells may play a potential role in retinal regeneration,BAC-Dkk3-EGFPmice could be useful for retinal regeneration studies.
Caries Is the Main Cause for Dental Pain in Childhood: Findings from a Birth Cohort
Authors: Boeira G.F. , Correa M.B. , Peres K.G. , Peres M.A. , Santos I.S. , Matijasevich A. , Barros A.J.D. , Demarco F.F.
Published: July 2012

Aim: The aim of the study was to evaluate the prevalence of dental pain in preschool children and its association with socioeconomic, demographic, clinical, and behavior variables. Subjects and Methods: The study was nested in a population-based birth cohort from Pelotas, Brazil, started in 2004. A sample of 1,129 children aged 5 years was dentally examined, and their mothers were interviewed. Exploratory variables included demographics, socioeconomic status, mothers’ oral health status and associated behaviors, and caries in primary teeth. Data were analyzed using multivariable Poisson regression. Results: The prevalence of dental pain was 16.5% (95% CI: 14.4–18.8). Multivariate analysis showed that dark-skinned children (prevalence ratio, PR = 1.6, 95% CI: 1.1–2.4) from low socioeconomic level (PR 1.9, 1.2–3.0) whose mothers had less than 4 years of education (PR 1.9, 1.0–3.6), from mothers with less than 10 teeth in at least one arch (PR 1.7, 1.2–2.5) and less than 10 in two arches (PR 1.6, 1.0–2.6), and those with high caries prevalence at the age of 5 years (PR 4.8, 3.3–7.1) were more likely to experience dental pain. Conclusions: Unrestored caries is the main factor associated with dental pain in childhood. Socioeconomic aspects and family context in which dental pain occurs should also be taken into account when dental pain preventive measures are implemented.
Effect of Safflower Oil on the Protective Properties of the in situ Formed Salivary Pellicle
Authors: Hannig C. , Wagenschwanz C. , Pötschke S. , Kümmerer K. , Kensche A. , Hoth-Hannig W. , Hannig M.
Published: July 2012

Aim: The prevalence of dental erosion is still increasing. A possible preventive approach might be rinsing with edible oils to improve the protective properties of the pellicle layer. This was tested in the present in situ study using safflower oil. Methods: Pellicle formation was carried out in situ on bovine enamel slabs fixed buccally to individual upper jaw splints (6 subjects). After 1 min of pellicle formation subjects rinsed with safflower oil for 10 min, subsequently the samples were exposed in the oral cavity for another 19 min. Enamel slabs without oral exposure and slabs exposed to the oral cavity for 30 min without any rinse served as controls. After pellicle formation in situ, slabs were incubated in HCl (pH 2; 2.3; 3) for 120 s, and kinetics of calcium and phosphate release were measured photometrically (arsenazo III, malachite green). Furthermore, the ultrastructure of the pellicles was evaluated by transmission electron microscopy (TEM). Results: Pellicle alone reduced erosive calcium and phosphate release significantly at all pH values. Pellicle modification by safflower oil resulted in an enhanced calcium loss at all pH values and caused an enhanced phosphate loss at pH 2.3. TEM indicated scattered accumulation of lipid micelles and irregular vesicle-like structures attached to the oil-treated pellicle layer. Acid etching affected the ultrastructure of the pellicle irrespective of oil rinsing. Conclusion: The protective properties of the pellicle layer against extensive erosive attacks are limited and mainly determined by pH. The protective effects are modified and reduced by rinses with safflower oil.
Observation-to-Imitate Plus Practice Could Add Little to Physical Therapy Benefits Within 31 Days of Stroke
Authors: Cowles Tracy , Clark Allan , Mares Kathryn , Peryer Guy , Stuck Rebecca , Pomeroy Valerie
Published: July 2012

Background and Purpose. Observation of action with intention-to-imitate (OTI) might enhance motor recovery. This early phase trial investigated whether OTI followed by physical practice (OTI + PP) enhanced the benefits of conventional physical therapy (CPT) on upper limb recovery early after stroke. Methods. Participants were 3 to 31 days poststroke. They had substantial paresis and ability to imitate action with their ipsilesional arm. After baseline measures, participants were randomized to either OTI + PP in addition to CPT or to CPT only. Outcome measures were made after 15 days of treatment. The measurement battery was the Motricity Index (MI) and the Action Research Arm Test (ARAT). Change, baseline to outcome, was examined using the Wilcoxon test for within group and Mann–Whitney U test for between groups. Results. Sixty-five of 570 stroke survivors were eligible, 55 were able to imitate, 37 gave informed consent, 7 were transferred out of area before baseline, and 29 were randomized. Outcome measures were completed with 13 CPT participants and 9 OTI + PP participants. Both groups showed statistically significant improvements for the MI (CPT median change 8, P = .003; OTI + PP median change 10, P = .012) but the median (95% confidence interval [CI]) between-group difference was 0.0 (−11, 16), P = 1.000. For the ARAT, only the CPT group showed a statistically significant improvement (median 9, P = .006). The median (95% CI) between-group difference of 1.0 (−18, 23) was not statistically significant ( P = .815). Conclusions. These findings suggest that OTI + PP might add little to the benefits of CPT early after stroke.
Improvement After Constraint-Induced Movement Therapy
Authors: Kitago Tomoko , Liang Johnny , Huang Vincent S. , Hayes Sheila , Simon Phyllis , Tenteromano Laura , Lazar Ronald M. , Marshall Randolph S. , Mazzoni Pietro , Lennihan Laura , Krakauer John W.
Published: July 2012

Background. Constraint-induced movement therapy (CIMT) has proven effective in increasing functional use of the affected arm in patients with chronic stroke. The mechanism of CIMT is not well understood. Objective. To demonstrate, in a proof-of-concept study, the feasibility of using kinematic measures in conjunction with clinical outcome measures to better understand the mechanism of recovery in chronic stroke patients with mild to moderate motor impairments who undergo CIMT. Methods. A total of 10 patients with chronic stroke were enrolled in a modified CIMT protocol over 2 weeks. Treatment response was assessed with the Action Research Arm Test (ARAT), the Upper-Extremity Fugl-Meyer score (FM-UE), and kinematic analysis of visually guided arm and wrist movements. All assessments were performed twice before the therapeutic intervention and once afterward. Results. There was a clinically meaningful improvement in ARAT from the second pre-CIMT session to the post-CIMT session compared with the change between the 2 pre-CIMT sessions. In contrast, FM-UE and kinematic measures showed no meaningful improvements. Conclusions. Functional improvement in the affected arm after CIMT in patients with chronic stroke appears to be mediated through compensatory strategies rather than a decrease in impairment or return to more normal motor control. We suggest that future large-scale studies of new interventions for neurorehabilitation track performance using kinematic analyses as well as clinical scales.
Effect of incorporation of zirconia layer upon physical and mechanical properties of investment casting ceramic shell
Authors: Yuan C , Withey P A , Blackburn S
Published: July 2012

Post-heat treatment recrystallisation is a significant cause of scrap in single crystal component production. This defect could be prevented by a reduction in the mechanical strength of the shell after the metal has solidified. Addition of a zirconia layer, to produce large cracks around grain boundaries and among the large grains during phase transformations, was considered as a method of reducing sintered strength. In this study, two types of zirconia stucco, monoclinic and partially stabilised, were introduced into the shell. The effect of the incorporation of a zirconia layer on the microstructure and mechanical properties of the shell were investigated. Shell with a monoclinic zirconia additional layer showed no reduction in the green strength but a better performance in high temperature deformation tolerance, maintaining shell performance during wax removal and metal casting. The shell strength after alloy solidification is reduced, suggesting that a reduction in recrystallisation may be possible with this method.
Effect of C/C preform density on microstructure and mechanical properties of C/C–SiC composites prepared by alloyed reactive melt infiltration
Authors: Tong Y G , Bai S X , Zhang H , Ye Y C
Published: July 2012

Low cost C/C–SiC composites were prepared by alloyed reactive melt infiltration. Effects of the density of C/C preforms on mechanical properties and microstructure of the C/C–SiC composites are reviewed. The results show that with increasing the density of C/C preforms, the flexural strength of the resulting composites increases, while the density of the composites decreases. The flexural strength can reach 341 MPa for the composite produced from the C/C preform of 1·3 g cm−3. The phases in the composites produced from low density C/C preforms are Si, SiC, ZrSi2 and carbon, while no Si phase is found in the composites with high density C/C preforms. Furthermore, the mechanism of the microstructure evolution of the C/C–SiC composites is proposed.
Mapping the polysaccharide degradation potential of Aspergillus niger
Authors: Andersen Mikael R , Giese Malene , de Vries Ronald P , Nielsen Jens
Published: July 2012

Background

The degradation of plant materials by enzymes is an industry of increasing importance. For sustainable production of second generation biofuels and other products of industrial biotechnology, efficient degradation of non-edible plant polysaccharides such as hemicellulose is required. For each type of hemicellulose, a complex mixture of enzymes is required for complete conversion to fermentable monosaccharides. In plant-biomass degrading fungi, these enzymes are regulated and released by complex regulatory structures. In this study, we present a methodology for evaluating the potential of a given fungus for polysaccharide degradation.

Results

Through the compilation of information from 203 articles, we have systematized knowledge on the structure and degradation of 16 major types of plant polysaccharides to form a graphical overview. As a case example, we have combined this with a list of 188 genes coding for carbohydrate-active enzymes fromAspergillus niger, thus forming an analysis framework, which can be queried. Combination of this information network with gene expression analysis on mono- and polysaccharide substrates has allowed elucidation of concerted gene expression from this organism. One such example is the identification of a full set of extracellular polysaccharide-acting genes for the degradation of oat spelt xylan.

Conclusions

The mapping of plant polysaccharide structures along with the corresponding enzymatic activities is a powerful framework for expression analysis of carbohydrate-active enzymes. Applying this network-based approach, we provide the first genome-scale characterization of all genes coding for carbohydrate-active enzymes identified inA. niger.
Making birthing safe for Pakistan women: a cluster randomized trial
Authors: Khan Muhammad Amir , Mirza Shirin , Ahmed Maqsood , Rasheed Akhtar , Khan Amanullah , Walley John , Nisar Nailah
Published: July 2012

Background

Two out of three neonatal deaths occur in just 10 countries and Pakistan stands third among them. Maternal mortality is also high with most deaths occurring during labor, birth, and first few hours after birth. Enhanced access and utilization of skilled delivery and emergency obstetric care is the demonstrated strategy in reducing maternal and neonatal mortality. This trial aims to compare reduction in neonate mortality and utilization of available safe birthing and Emergency Obstetric and Neonatal Care services among pregnant mothers receiving ‘structured birth planning’, and/or ‘transport facilitation’ compared to routine care.

Methods

A pragmatic cluster randomized trial, with qualitative and economic studies, will be conducted in Jhang, Chiniot and Khanewal districts of Punjab, Pakistan, from February 2011 to May 2013. At least 29,295 pregnancies will be registered in the three arms, seven clusters per arm; 1) structured birth planning and travel facilitation, 2) structured birth planning, and 3) control arm. Trial will be conducted through the Lady Health Worker program. Main outcomes are difference in neonatal mortality and service utilization; maternal mortality being the secondary outcome. Cluster level analysis will be done according to intention-to-treat.

Discussion

A nationwide network of about 100,000 lady health workers is already involved in antenatal and postnatal care of pregnant women. They also act as “gatekeepers” for the child birthing services. This gate keeping role mainly includes counseling and referral for skill birth attendance and travel arrangements for emergency obstetric care (if required). The review of current arrangements and practices show that the care delivery process needs enhancement to include adequate information provision as well as informed “decision” making and planned “action” by the pregnant women. The proposed three-year research is to develop, through national technical working group process, and then test a set of arrangements for achieving the enhanced utilization of safe birthing services.

Trial registration

Current Controlled Trials ISRCTN86264432
ZIC1 modulates cell-cycle distributions and cell migration through regulation of sonic hedgehog, PI3K and MAPK signaling pathways in gastric cancer
Authors: Zhong Jing , Chen Shujie , Xue Meng , Du Qin , Cai Jianting , Jin Hongchuan , Si Jianmin , Wang Liangjing
Published: July 2012

Background

ZIC1, a vital transcription factor with zinc finger domains, has been implicated in the process of neural development. We previously showed that ZIC1 may function as a tumour suppressor in gastrointestinal cancers. However, the molecular mechanism underlying ZIC1 participation in tumour progression remains unknown.

Methods

The role of ZIC1 on cell proliferation and migration was examined. The regulation of sonic hedgehog (Shh), phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) signaling pathways after ectopic expression of ZIC1 in gastric cancer cells were evaluated.

Results

Overexpression of ZIC1 contributes to the inhibition of cell proliferation migration and cell-cycle distribution in gastric cancer. The modulation of G1/S checkpoint by ZIC1 is mainly mediated through the regulation of cyclin-dependent kinases (p21 Waf1/Cip1, p27 Kip1 and cyclin D1). In addition, ZIC1 can inactivate the level of phospholated Akt and Erk1/2, and transcriptionally regulate sonic hedgehog (Shh) signaling, thus leading to regulate the expression of p21 Waf1/Cip1 and cyclin D1. Finally, we have systemically identified ZIC1 downstream targets by cDNA microarray analysis and revealed that 132 genes are down-regulated and 66 genes are up-regulated after transfection with ZIC1 in gastric cancer cells. These candidate genes play critical roles in cell proliferation, cell cycle and cell motility.

Conclusions

Overexpression of ZIC1 results in inactivation of Shh, PI3K and MAPK signaling pathways, as well as regulation of multiple downstream targets which are essential for the development and progression of gastric cancer. ZIC1 serves as a potential therapeutic target for gastric cancer.
Factors associated with suicidal behaviors in mainland China: a meta-analysis
Authors: Li Ying , Li Yafei , Cao Jia
Published: July 2012

Background

Suicide is a major public health issue in China. Studies of suicide risk factors have reported both inconsistent and inconclusive results. This review aimed to determine suicide risk factors in China.

Methods

Medline/PubMed, EMBASE, CNKI (China National Knowledge Infrastructure) and VIP (Chinese Journal of Science and Technology of VIP) were searched for relevant reports. Two investigators independently assessed the eligibility of identified studies and extracted data. Pooled odds ratios (and 95% confidence intervals) were calculated for each factor with Revman 5.0.

Results

Forty-four studies with 192,362 subjects were included. The pooled results indicated that mood disorders and stressful life events (physical illness, suicide of relatives) increased the risk of suicide ideation among the entire population. Socio-family environment (single or remarried parent, study pressure and academic achievement) and unhealthy behaviors (smoking, alcohol drinking, and drug use) were risk factors for suicide ideation among youth. Unhealthy behaviors (smoking and alcohol drinking), mood disorders, and stressful life events (suicide of relatives) were the main risk factors for attempted suicide. Persons living in rural areas, and those with lower education, mood disorders, and/or a history of negative life events had a higher risk of completed suicide. In China, before 2000, females had a significantly higher rate of completed suicide than males, while after 2000, no significant gender difference was found.

Conclusions

Socio-family environment, lifestyle, life events and psychiatric/psychological factors are associated with suicidal behaviors in China. Further case–control or cohort studies are needed to better understand suicide behaviors in China. Meanwhile, there is an urgent need for comprehensive studies of suicide interventions among high-risk populations.
Field performance of transgenic citrus trees: Assessment of the long-term expression of uidA and nptIItransgenes and its impact on relevant agronomic and phenotypic characteristics
Authors: Pons Elsa , Peris Josep E , Peña Leandro
Published: July 2012

Background

The future of genetic transformation as a tool for the improvement of fruit trees depends on the development of proper systems for the assessment of unintended effects in field-grown GM lines. In this study, we used eight transgenic lines of two different citrus types (sweet orange and citrange) transformed with the marker genes β-glucuronidase (uidA) and neomycin phosphotransferase II (nptII) as model systems to study for the first time in citrus the long-term stability of transgene expression and whether transgene-derived pleiotropic effects occur with regard to the morphology, development and fruit quality of orchard-grown GM citrus trees.

Results

The stability of the integration and expression of the transgenes was confirmed in 7-year-old, orchard-grown transgenic lines by Southern blot analysis and enzymatic assays (GUS and ELISA NPTII), respectively. Little seasonal variation was detected in the expression levels between plants of the same transgenic line in different organs and over the 3 years of analysis, confirming the absence of rearrangements and/or silencing of the transgenes after transferring the plants to field conditions. Comparisons between the GM citrus lines with their non-GM counterparts across the study years showed that the expression of these transgenes did not cause alterations of the main phenotypic and agronomic plant and fruit characteristics. However, when comparisons were performed between diploid and tetraploid transgenic citrange trees and/or between juvenile and mature transgenic sweet orange trees, significant and consistent differences were detected, indicating that factors other than their transgenic nature induced a much higher phenotypic variability.

Conclusions

Our results indicate that transgene expression in GM citrus remains stable during long-term agricultural cultivation, without causing unexpected effects on crop characteristics. This study also shows that the transgenic citrus trees expressing the selectable marker genes that are most commonly used in citrus transformation were substantially equivalent to the non-transformed controls with regard to their overall agronomic performance, as based on the use of robust and powerful assessment techniques. Therefore, future studies of the possible pleiotropic effects induced by the integration and expression of transgenes in field-grown GM citrus may focus on the newly inserted trait(s) of biotechnological interest.
Genetic diversity of expressed Plasmodium falciparum var genes from Tanzanian children with severe malaria
Authors: Mugasa Joseph , Qi Weihong , Rusch Sebastian , Rottmann Matthias , Beck Hans-Peter
Published: July 2012

Background

Severe malaria has been attributed to the expression of a restricted subset of the var multi-gene family, which encodes for Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1). PfEMP1 mediates cytoadherence and sequestration of infected erythrocytes into the post-capillary venules of vital organs such as the brain, lung or placenta. var genes are highly diverse and can be classified in three major groups (ups A, B and C) and two intermediate groups (B/A and B/C) based on the genomic location, gene orientation and upstream sequences. The genetic diversity of expressed var genes in relation to severity of disease in Tanzanian children was analysed.

Methods

Children with defined severe (SM) and asymptomatic malaria (AM) were recruited. Full-length var mRNA was isolated and reversed transcribed into var cDNA. Subsequently, the DBL and N-terminal domains, and up-stream sequences were PCR amplified, cloned and sequenced. Sequences derived from SM and AM isolates were compared and analysed.

Results

The analysis confirmed that the var family is highly diverse in natural Plasmodium falciparum populations. Sequence diversity of amplified var DBL-1α and upstream regions showed minimal overlap among isolates, implying that the var gene repertoire is vast and most probably indefinite in endemic areas. var DBL-1α sequences from AM isolates were more diverse with more singletons found (p<0.05) than those from SM infections. Furthermore, few var DBL-1α sequences from SM patients were rare and restricted suggesting that certain PfEMP1 variants might induce severe disease.

Conclusions

The genetic sequence diversity of var genes of P. falciparum isolates from Tanzanian children is large and its relationship to disease severity has been studied. Observed differences suggest that different var genes might have fundamentally different roles in the host-parasite interaction. Further research is required to examine clear disease-associations of var gene subsets in different geographical settings. The importance of very strict clinical definitions and appropriate large control groups needs to be emphasized for future studies on disease associations of PfEMP1.
The role of nitric oxide on rosuvastatin-mediated S-nitrosylation and translational proteomes in human umbilical vein endothelial cells
Authors: Huang Bin , Li Fu An , Wu Chien Hsing , Wang Danny Ling
Published: July 2012

Background

The pleiotropic effects of 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins), which are independent from their cholesterol-lowering action, have been widely recognized in various biological systems. Statins can affect endothelial homeostasis, which is partly modulated by the production of nitric oxide (NO). However, it is unclear how statin/NO-mediated posttranslational S-nitrosylation of endothelial proteins and changes in translational profiles may benefit endothelial integrity. Therefore, it is important to understand the statin/NO-mediated S-nitrosylation in endothelial cells.

Results

Rosuvastatin treatment of human umbilical vein endothelial cells (ECs) enhanced the enzymatic activity of endothelial nitric oxide synthase (eNOS) and the expression of 78 S-nitrosoproteins. Among these S-nitrosoproteins, we identified 17 proteins, including protein disulfide bond isomerase, phospholipase C, transaldolase and heat shock proteins. Furthermore, a hydrophobic Cys66 was determined as the S-nitrosylation site of the mitochondrial HSP70. In addition to the statin-modulated posttranslational S-nitrosylation, changes in the NO-mediated translational proteome were also observed. Seventeen major proteins were significantly upregulated after rosuvastatin treatment. However, 12 of these proteins were downregulated after pretreating ECs with an eNOS inhibitor (L-NAME), which indicated that their expression was modulated by NO.

Conclusions

ECs treated with rosuvastatin increase eNOS activation. The increased NO production is involved in modulating S-nitrosylation and translation of proteins. We provide further evidence of the pleiotropic effect of rosuvastatin on endothelial physiology.
Inferring domain-domain interactions from protein-protein interactions in the complex network conformation
Authors: Chen Chen , Zhao Jun-Fei , Huang Qiang , Wang Rui-Sheng , Zhang Xiang-Sun
Published: July 2012

Background

As protein domains are functional and structural units of proteins, a large proportion of protein-protein interactions (PPIs) are achieved by domain-domain interactions (DDIs), many computational efforts have been made to identify DDIs from experimental PPIs since high throughput technologies have produced a large number of PPIs for different species. These methods can be separated into two categories: deterministic and probabilistic. In deterministic methods, parsimony assumption has been utilized. Parsimony principle has been widely used in computational biology as the evolution of the nature is considered as a continuous optimization process. In the context of identifying DDIs, parsimony methods try to find a minimal set of DDIs that can explain the observed PPIs. This category of methods are promising since they can be formulated and solved easily. Besides, researches have shown that they can detect specific DDIs, which is often hard for many probabilistic methods. We notice that existing methods just view PPI networks as simply assembled by single interactions, but there is now ample evidence that PPI networks should be considered in a global (systematic) point of view for it exhibits general properties of complex networks, such as 'scale-free' and 'small-world'.

Results

In this work, we integrate this global point of view into the parsimony-based model. Particularly, prior knowledge is extracted from these global properties by plausible reasoning and then taken as input. We investigate the role of the added information extensively through numerical experiments. Results show that the proposed method has improved performance, which confirms the biological meanings of the extracted prior knowledge.

Conclusions

This work provides us some clues for using these properties of complex networks in computational models and to some extent reveals the biological meanings underlying these general network properties.
Unilateral testicular seminoma with simultaneous contralateral torsion: a case report
Authors: Taguchil Kazumi , Yasui Takahiro , Naiki Taku , Umemoto Yukihiro , Kojima Yoshiyuki , Kawai Noriyasu , Tozawa Keiichi , Hayashi Yutaro , Kohri Kenjiro
Published: July 2012

Introduction

Testicular germ cell tumors are the most common malignancies in men. Testicular torsion is also a scrotal phenomenon seen in adolescence and adulthood. The co-occurrence of these two scrotal disorders is extremely rare.

Case presentation

A 28-year-old East Asian man presented at our hospital with painless bilateral scrotal swelling. Both scrotal ultrasonography and computed tomography findings showed bilateral testicular tumors, and magnetic resonance imaging demonstrated a lack of enhancement in his right testis, indicating a hemorrhagic infarction and a left testicular tumor. After a bilateral orchiectomy, the intraoperative and histopathological findings revealed a left seminoma with a complicating contralateral testicular torsion that had developed with hemorrhagic infarction.

Conclusion

Testicular germ cell tumor with contralateral torsion is extremely rare. We could differentiate this case from bilateral testicular tumors appropriately using magnetic resonance imaging, and suggest that magnetic resonance imaging examination may be necessary to diagnose bilateral testicular masses.
A clinical "near miss" highlights risk management issues surrounding ultrasound-guided and wire-localised breast resections
Authors: Leff Daniel Richard , Vincent Charles , Al-Mufti Ragheed , Cunningham Deborah , Darzi Ara , Hadjiminas Dimitri J
Published: July 2012

Background

The introduction of the National Health Service (NHS) Breast Screening Programme has led to a considerable increase in the detection of impalpable breast cancer. Patients with impalpable breast cancer typically undergo oncological resection facilitated either by the insertion of guide wires placed stereo-tactically or through ultra-sound guided skin markings to delineate the extent of a lesion. The need for radiological interventions on the day of surgery adds complexity and introduces the risk that a patient may accidentally transferred to the operating room directly without the image guidance procedure.

Case report

A case is described of a patient who required a pre-operative ultrasound scan in order to localise an impalpable breast cancer but who was accidentally taken directly to the operating theatre (OR) and anaesthetised without pre-operative intervention. The radiologist was called to the OR and an on-table ultrasound was performed without further consequence.

Conclusion

It is evident that breast cancer patients undergoing image-guided resection are exposed to an additional layer of clinical risks. These risks are not offset by the World Health Organisation surgical safety checklist in its present guise. Here, we review a number of simple and inexpensive changes to the system that may improve the safety of the breast cancer patient undergoing surgery.
A novel energy-aware cluster head selection based on particle swarm optimization for wireless sensor networks
Authors: Singh Buddha , Lobiyal Daya Krishan
Published: July 2012

The wireless sensor networks have long been an attractive field to the researchers and scientists for its ease in deployment and maintenance. In this research, we focus on the maximization of network lifetime which has become a critical issue in sensor networks. Clustered organization of nodes with aggregation of data at the cluster head becomes one of the significant means to extend life expectancy of the network. This paper proposes Particle Swarm Optimization (PSO) approach for generating energy-aware clusters by optimal selection of cluster heads. The PSO eventually reduces the cost of locating optimal position for the head nodes in a cluster. In addition, we have implemented the PSO-based approach within the cluster rather than base station, which makes it a semi-distributed method. The selection criteria of the objective function are based on the residual energy, intra-cluster distance, node degree and head count of the probable cluster heads. Furthermore, influence of the expected number of packet retransmissions along the estimated path towards the cluster head is also reflected in our proposed energy consumption model. The performance evaluation of our proposed technique is carried out with respect to the well-known cluster-based sensor network protocols, LEACH-C and PSO-C respectively. Finally, the simulation clarifies the effectiveness of our proposed work over its comparatives in terms of network lifetime, average packet transmissions, cluster head selection rounds supported by PSO and average energy consumption.
Application of aqueous extracts of coffee senna for control of mild steel corrosion in acidic environments
Authors: Akalezi Chris O , Enenebaku Conrad K , Oguzie Emeka E
Published: July 2012

Background

The inhibitive effect of the aqueous extract of Coffee senna (CS) on the corrosion of mild steel in 1 M HCl and 0.5 M H2SO4 solutions was investigated by weight loss measurement as well as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements.

Result

The extract was found to efficiently inhibit the corrosion process in both environments and inhibition efficiency increased with extract concentration as well as rise in temperature. Data from electrochemical measurements suggest that the extract functioned by adsorption of the organic matter on the metal/corrodent interface, inhibiting both the anodic and cathodic half reactions of the corrosion process. Adsorption of the extract organic matter was approximated by the Langmuir isotherm. The adsorption behavior of selected organic constituents of the extract on the metal surface was assessed at the molecular level, in the framework of the density functional theory.

Conclusion

This study clearly shows the potentials of CS extract for control of mild steel corrosion in acidic environment.
Clinical Leadership in Quality and Safety at the Point of Care
Authors: Caldwell Gordon
Published: July 2012

Consultants have considerable freedom and power to improve the quality and safety of clinical care within their services. Whatever happens to healthcare in the future, patients acutely unwell with critical illnesses will be taken to hospital. The priority work of acute hospitals will always be to treat these patients with high-quality effective clinical care to swiftly and safely restore their health so that they can resume living outside hospital. For a small proportion of patients the work is to anticipate and provide for a calm end of life. Integral to this work is also the training of the next generation of healthcare professionals. Over the last five years I have been working to improve quality and safety at the point of care in acute general medicine. I discuss some of the successes and hope to open the reader's eyes to the potential for improvement in acute care processes, if clinicians and managers work together to optimize working at the point of care.
A Comparative Study of Personality Descriptors Attributed to the Deaf, the Blind, and Individuals with No Sensory Disability
Authors: Cambra Cristina
Published: July 2012

During the building of self-concept, one's self-perception is influenced by the attitudes and levels of acceptance of significant individuals in one's immediate environment and in society as a whole. This study explores the social image of the deaf, beginning with an analysis of personality characteristics attributed to this group. The resulting profile is then compared to those of two other previously assessed groups: the blind and those with no sensory disability. A sample of 222 university students evaluated personality descriptors as applied to the three groups by means of a semantic differential. For certain personality descriptors, the students had different impressions of the three groups. Results show that certain negative stereotypes still mark the social representation of deafness. Instances of familiarity or friendship between haring people and deaf people serve generally to mitigate such stereotypes
Critical Teaching Incidents: Recollections of Deaf College Students
Authors: Lang Harry G. , Dowaliby Fred J. , Anderson Hugh P.
Published: July 2012

In interviews with 56 deaf college students, we collected accounts of 839 "critical incidents" describing effective and ineffective teaching. From those incidents, 33 specific teaching characteristics were derived and were analyzed in relation to teacher, student, and course variables. Our primary goal was to identify the teaching characteristics underlying deaf students' recollections about their classroom learning experiences. The most frequently mentioned characteristics are similar to those found in studies of hearing college students, particularly within the domain of Teacher Affect. The teacher's ability to communicate clearly in sign language, however, was not only a characteristic unique to deaf college students but also the most frequently occurring characteristic of effective teaching in this study.