bluuebunny/crossref_metadata_2025 huggingface dataset:
Library Screen Identifies Enterococcus faecalis CcpA, the Catabolite Control Protein A, as an Effector of Ace, a Collagen Adhesion Protein Linked to Virulence
Authors: Gao Peng , Pinkston Kenneth L. , Bourgogne Agathe , Cruz Melissa R. , Garsin Danielle A. , Murray Barbara E. , Harvey Barrett R.
Published: August 2013

The
Enterococcus faecalis
cell wall-anchored protein Ace is an important virulence factor involved in cell adhesion and infection. Expression of Ace on the cell surface is affected by many factors, including stage of growth, culture temperature, and environmental components, such as serum, urine, and collagen. However, the mechanisms that regulate or modulate Ace display are not well understood. With interest in identifying genes associated with Ace expression, we utilized a whole-cell enzyme-linked immunosorbent assay (ELISA)-based screening method to identify mutants from a transposon insertion mutant library which exhibited distinct Ace surface expression profiles. We identified a
ccpA
insertion mutant which showed significantly decreased levels of Ace surface expression at early growth phase versus those of wild-type OG1RF. Confirmation of the observation was achieved through flow cytometry and complementation analysis. Compared to the wild type, the
E. faecalis ccpA
mutant had an impaired ability to adhere to collagen when grown to early exponential phase, consistent with the lack of Ace expression in the early growth phase. As a key component of carbon catabolite regulation, CcpA has been previously reported to play a critical role in regulating expression of proteins involved in
E. faecalis
carbohydrate uptake and utilization. Our discovery is the first to associate CcpA with the production of a major
E. faecalis
virulence factor, providing new insights into the regulation of
E. faecalis
pathogenesis.
MacA, a Periplasmic Membrane Fusion Protein of the Macrolide Transporter MacAB-TolC, Binds Lipopolysaccharide Core Specifically and with High Affinity
Authors: Lu Shuo , Zgurskaya Helen I.
Published: August 2013

The
Escherichia coli
MacAB-TolC transporter has been implicated in efflux of macrolide antibiotics and secretion of enterotoxin STII. In this study, we found that purified MacA, a periplasmic membrane fusion protein, contains one tightly bound rough core lipopolysaccharide (R-LPS) molecule per MacA molecule. R-LPS was bound specifically to MacA protein with affinity exceeding that of polymyxin B. Sequence analyses showed that MacA contains two high-density clusters of positively charged amino acid residues located in the cytoplasmic N-terminal domain and the periplasmic C-terminal domain. Substitutions in the C-terminal cluster reducing the positive-charge density completely abolished binding of R-LPS. At the same time, these substitutions significantly reduced the functionality of MacA in the protection of
E. coli
against macrolides
in vivo
and in the
in vitro
MacB ATPase stimulation assays. Taken together, our results suggest that R-LPS or a similar glycolipid is a physiological substrate of MacAB-TolC.
Pasteurella multocida Heddleston Serovar 3 and 4 Strains Share a Common Lipopolysaccharide Biosynthesis Locus but Display both Inter- and Intrastrain Lipopolysaccharide Heterogeneity
Authors: Harper Marina , St. Michael Frank , John Marietta , Vinogradov Evgeny , Steen Jennifer A. , van Dorsten Lieke , Steen Jason A. , Turni Conny , Blackall Patrick J. , Adler Ben , Cox Andrew D. , Boyce John D.
Published: August 2013

Pasteurella multocida
is a Gram-negative multispecies pathogen and the causative agent of fowl cholera, a serious disease of poultry which can present in both acute and chronic forms. The major outer membrane component lipopolysaccharide (LPS) is both an important virulence factor and a major immunogen. Our previous studies determined the LPS structures expressed by different
P. multocida
strains and revealed that a number of strains belonging to different serovars contain the same LPS biosynthesis locus but express different LPS structures due to mutations within glycosyltransferase genes. In this study, we report the full LPS structure of the serovar 4 type strain, P1662, and reveal that it shares the same LPS outer core biosynthesis locus, L3, with the serovar 3 strains P1059 and Pm70. Using directed mutagenesis, the role of each glycosyltransferase gene in LPS outer core assembly was determined. LPS structural analysis of 23 Australian field isolates that contain the L3 locus revealed that at least six different LPS outer core structures can be produced as a result of mutations within the LPS glycosyltransferase genes. Moreover, some field isolates produce multiple but related LPS glycoforms simultaneously, and three LPS outer core structures are remarkably similar to the globo series of vertebrate glycosphingolipids. Our in-depth analysis showing the genetics and full range of
P. multocida
lipopolysaccharide structures will facilitate the improvement of typing systems and the prediction of the protective efficacy of vaccines.
Transposon Mutagenesis Identified Chromosomal and Plasmid Genes Essential for Adaptation of the Marine Bacterium Dinoroseobacter shibae to Anaerobic Conditions
Authors: Ebert Matthias , Laaß Sebastian , Burghartz Melanie , Petersen Jörn , Koßmehl Sebastian , Wöhlbrand Lars , Rabus Ralf , Wittmann Christoph , Tielen Petra , Jahn Dieter
Published: August 2013

Anaerobic growth and survival are integral parts of the life cycle of many marine bacteria. To identify genes essential for the anoxic life of
Dinoroseobacter shibae
, a transposon library was screened for strains impaired in anaerobic denitrifying growth. Transposon insertions in 35 chromosomal and 18 plasmid genes were detected. The essential contribution of plasmid genes to anaerobic growth was confirmed with plasmid-cured
D. shibae
strains. A combined transcriptome and proteome approach identified oxygen tension-regulated genes. Transposon insertion sites of a total of 1,527 mutants without an anaerobic growth phenotype were determined to identify anaerobically induced but not essential genes. A surprisingly small overlap of only three genes (
napA
,
phaA
, and the Na
+
/P
i
antiporter gene Dshi_0543) between anaerobically essential and induced genes was found. Interestingly, transposon mutations in genes involved in dissimilatory and assimilatory nitrate reduction (
napA
,
nasA
) and corresponding cofactor biosynthesis (genomic
moaB
,
moeB
, and
dsbC
and plasmid-carried
dsbD
and
ccmH
) were found to cause anaerobic growth defects. In contrast, mutation of anaerobically induced genes encoding proteins required for the later denitrification steps (
nirS
,
nirJ
,
nosD
), dimethyl sulfoxide reduction (
dmsA1
), and fermentation (
pdhB1
,
arcA
,
aceE
,
pta
,
acs
) did not result in decreased anaerobic growth under the conditions tested. Additional essential components (ferredoxin,
cccA
) of the anaerobic electron transfer chain and central metabolism (
pdhB
) were identified. Another surprise was the importance of sodium gradient-dependent membrane processes and genomic rearrangements via viruses, transposons, and insertion sequence elements for anaerobic growth. These processes and the observed contributions of cell envelope restructuring (
lysM
,
mipA
,
fadK
), C4-dicarboxylate transport (
dctM1
,
dctM3
), and protease functions to anaerobic growth require further investigation to unravel the novel underlying adaptation strategies.
Reflection: moving from a mandatory ritual to meaningful professional development
Authors: Murdoch-Eaton Deborah , Sandars John
Published: August 2013

Reflection has become established as a key principle underpinning maintenance of standards within professional education and practice. A requirement to evidence reflection within performance review is intended to develop a transformative approach to practice, identify developmental goals, and ultimately, improve healthcare. However, some applications have taken an excessively instrumental approach to the evidencing of reflection, and while they have provided useful templates or framing devices for recording individualistic reflective practice, they potentially have distorted the original intentions. This article revisits the educational theory underpinning the importance of reflection for enhancing performance and considers how to enhance its value within current paediatric practice.
Breast milk and cognitive development—the role of confounders: a systematic review
Authors: Walfisch Asnat , Sermer Corey , Cressman Alex , Koren Gideon
Published: August 2013

Objectives

The association between breastfeeding and child cognitive development is conflicted by studies reporting positive and null effects. This relationship may be confounded by factors associated with breastfeeding, specifically maternal socioeconomic class and IQ.

Design

Systematic review of the literature.

Setting and participants

Any prospective or retrospective study, in any language, evaluating the association between breastfeeding and cognitive development using a validated method in healthy term infants, children or adults, was included.

Primary and secondary outcome measures

Extracted data included the study design, target population and sample size, breastfeeding exposure, cognitive development assessment tool used and participants’ age, summary of the results prior to, and following, adjustment for confounders, and all confounders adjusted for. Study quality was assessed as well.

Results

84 studies met our inclusion criteria (34 rated as high quality, 26 moderate and 24 low quality). Critical assessment of accepted studies revealed the following associations: 21 null, 28 positive, 18 null after adjusting for confounders and 17 positive—diminished after adjusting for confounders. Directionality of effect did not correlate with study quality; however, studies showing a decreased effect after multivariate analysis were of superior quality compared with other study groupings (14/17 high quality, 82%). Further, studies that showed null or diminished effect after multivariate analysis corrected for significantly more confounders (7.7±3.4) as compared with those that found no change following adjustment (5.6±4.5, p=0.04). The majority of included studies were carried out during childhood (75%) and set in high-income countries (85.5%).

Conclusions

Much of the reported effect of breastfeeding on child neurodevelopment is due to confounding. It is unlikely that additional work will change the current synthesis. Future studies should attempt to rigorously control for all important confounders. Alternatively, study designs using sibling cohorts discordant for breastfeeding may yield more robust conclusions.
Impact of the economic crisis on children's health in Catalonia: a before–after approach
Authors: Rajmil Luis , Medina-Bustos Antonia , Fernández de Sanmamed María-José , Mompart-Penina Anna
Published: August 2013

Objectives

To analyse changes in the family living conditions of children in Catalonia between 2006 and the 2010–2012 period, and to study associations between these changes and health outcomes.

Design

A before–after analysis of two cross-sectional surveys.

Setting

Population younger than 15 years of age from Catalonia, Spain.

Participants

Representative samples of children in the 2006 Catalan Health Survey (ESCA), baseline, before the crisis; n=2200) and the first four waves of ESCA 2010–2012 (after start of the crisis, n=1967).

Main outcome measures

Overweight/obesity, health behaviour, mental health and health-related quality of life (HRQOL). Logistic regression and multiple linear regression models were used to analyse the influence of changes in family conditions on outcome measures, including interaction terms to describe the potential influence of the study period on the results.

Results

The percentage of unemployed families rose from 9.1% (2006) to 20.6% (2010–2012), with inequalities by level of education. Overweight/obesity increased from 18.4% (95% CI 16.5% to 20.4%) to 26.9% (24.6% to 29.2%) in 2010–2012, and inequalities related to maternal education and employment status persisted. Eating habits have improved in 2010–2012 in disadvantaged families (ie, junk food consumption improved in families with a maternal primary education level; beta (B)=2.85; 0.83 to 4.88, for the survey interaction by primary education level). An improvement in HRQOL was found in the second survey (B=6.07; 4.15 to 7.99), although children whose mothers had a primary education showed poorer HRQOL scores in this survey than in 2006 (B=−4.14; −7.17 to −1.12).

Conclusions

Although some health-related behaviour improved during the study period, childhood obesity increased and inequalities in HRQOL appeared. Policy measures that fight against these inequalities should be urgently implemented to avoid their negative impact on the health of future generations of Catalans.
Graft-related disease progression in dura mater graft-associated Creutzfeldt-Jakob disease: a cross-sectional study
Authors: Sakai Kenji , Hamaguchi Tsuyoshi , Noguchi-Shinohara Moeko , Nozaki Ichiro , Takumi Ichiro , Sanjo Nobuo , Nakamura Yosikazu , Kitamoto Tetsuyuki , Saito Nobuhito , Mizusawa Hidehiro , Yamada Masahito
Published: August 2013

Objectives

Details of abnormal prion protein (PrPSc) propagation in the human central nervous system (CNS) are unclear. To assess the spread of PrPScthrough the human CNS, we evaluated dura mater graft-associated Creutzfeldt-Jakob disease (dCJD) cases focusing on sites of grafting and dCJD pathological subtypes.

Design

A cross-sectional study.

Setting

nationwide surveillance data of human prion diseases in Japan over the past 12 years were applied for the study.

Participants

Clinical data were obtained from 84 dCJD patients.

Outcome measures

The clinical courses in cases of dCJD were analysed according to the grafting sites (supratentorial and infratentorial groups) and the pathological subtypes (non-plaque and plaque types).

Results

Of the 84 cases of dCJD in this study, 36 (43%) were included in the supratentorial group and 39 (46%) were included in the infratentorial group. As initial manifestations, vertigo (p=0.007) and diplopia (p=0.041) were significantly more frequent in the infratentorial group than in the supratentorial group. During their clinical course, cerebellar signs appeared more frequently in the infratentorial group than in the supratentorial group (p=0.024). In the non-plaque type cases (n=53), the infratentorial group developed vertigo more frequently than the supratentorial group (p=0.017); moreover, cerebellar signs appeared more frequently in the infratentorial group (p=0.014). However, there was no significant difference between groups in the plaque type (n=18).

Conclusions

The high frequency of clinical manifestations related to brain stem and cerebellar dysfunction in the non-plaque type dCJD with infratentorial grafting suggests that PrPSccommonly shows direct propagation into the CNS from contaminated dura mater grafts.
Characteristics associated with requested and required accelerometer wear in children
Authors: Wells Sian L , Kipping Ruth R , Jago Russell , Brown Judith , Hucker Daniel , Blackett Ali , Lawlor Debbie A
Published: August 2013

Objective

To investigate characteristics associated with wearing an accelerometer for the required and requested time among 8-year-old to 10-year-old children.

Design

Cross-sectional.

Setting

60 Bristol and North Somerset primary schools taking part in the ‘Active for Life Year 5’ randomised controlled trial (RCT) in 2011.

Participants

2048 children, aged 8–10 years, invited to wear an accelerometer for 5 days of recording.

Primary outcome measure

Numbers meeting required wear-time for inclusion in main RCT analysis (≥8 h/day ≥3 days) and numbers meeting requested wear-time (≥8 h/day for all 5 days).

Results

817 (40%) of the children wore the accelerometer for the requested time and 1629 (80%) for the required time. In adjusted multivariable analyses the odds of wearing the accelerometer for the required time were greater in females as compared with males (OR 1.76 (1.42–2.18)), those with higher scores for reporting their mother restricted time on sedentary behaviours (1.26 (1.04–1.52) per increase of 1 on a 1–4 scale) and in children from schools with larger year group sizes (1.01 (1.00–1.02) per additional child). Living in a neighbourhood with higher levels of deprivation (0.49 (0.33–0.72) comparing highest to lowest third of the deprivation score) or reporting higher levels of weekday outdoor play (0.97 (0.94, 1.00) per 30 min more) were associated with reduced odds of meeting required time. Results were essentially the same for requested wear-time. Other characteristics, including child body mass index, were not associated with required or requested wear-time.

Conclusions

Only 40% of children wore the accelerometer for the requested time but 80% fulfilled the required criteria to be included in the main study analyses. Knowing which characteristics are associated with accelerometer wear could help target interventions to increase wear-time.
Impact of supplemental immunisation activity (SIA) campaigns on health systems: findings from South Africa
Authors: Verguet Stéphane , Jassat Waasila , Bertram Melanie Y , Tollman Stephen M , Murray Christopher J L , Jamison Dean T , Hofman Karen J
Published: August 2013

Background

Supplemental immunisation activity (SIA) campaigns provide children with an additional dose of measles vaccine and deliver other child health interventions including vitamin A supplements, deworming medications and oral polio vaccines. They also require the mobilisation of a large health workforce. We assess the impact of the implementation of SIA campaigns on selected routine child and maternal health services in South Africa (SA).

Methods

We use district-level monthly headcount data for 52 South African districts for the period 2001–2010, sourced from the District Health Information System, SA. The data include 12 child and maternal health headcount indicators including routine immunisation, and maternal and reproductive health indicators. We analyse the association between the implementation of the 2010 SIA campaign and the change (decrease/increase) in headcounts, using a linear regression model.

Results

We find a significant decrease for eight indicators. The total number of fully immunised children before age 1 decreased by 29% (95% CI 23% to 35%, p<0.001) during the month of SIA implementation; contraceptive use and antenatal visits decreased by 7–17% (p ≤ 0.02) and about 10% (p<0.001), respectively.

Conclusions

SIA campaigns may negatively impact health systems during the period of implementation by disrupting regular functioning and diverting resources from other activities, including routine child and maternal health services. SIA campaigns present multidimensional costs that need to be explicitly considered in benefit–cost assessments.
Religiosity and magic in some lithoiatric practices of European folk medicine
Authors: Aliverti Massimo
Published: August 2013

The use of rocks and stones for the treatment of ill people is present in the folk medicine of many European regions. Lithoiatric practices have a long history which started with the peoples living in prehistoric times and continued in the various civilizations that followed one another over the centuries in Europe right up to the present era. Rocks and stones (pertaining to mountains or hills, caverns or canals, streams or other damp places) have been variously used by mankind in therapeutic procedures in magic or religious settings, giving considerable prestige to some places where such practices were exercised. The present work deals with the symbolism of rocks in human cultures, also with reference to mythology. This essay takes into account many places of worship and the popular traditions connected to them, giving special attention to those that are in Italy.
Determination of Sodium Cromoglycate by a New Kinetic Spectrophotometric Method in Biological Samples
Authors: Keyvanfard Mohsen , Alizad Khadijeh , Shakeri Razieh
Published: August 2013

A new kinetic spectrophotometric method is described for the determination of ultratrace amounts of sodium cromoglycate (SCG). The method based on catalytic action of SCG on the oxidation of amaranth with periodate in acidic and micellar medium. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of the amaranth at 518 nm, for the first 4 min from initiation of the reaction. Calibration curve was linear in the range of 4.0−36.0 ng mL−1 SCG. The limit of detection is 2.7 ng mL−1 SCG. The relative standard deviation (RSD) for ten replicate analyses of 12, 20, and 28 ng mL−1 SCG was 0.40%, 0.32%, and 0.53%, respectively. The proposed method was used for the determination of SCG in biological samples.
Autoantibodies and the Immune Hypothesis in Psychotic Brain Diseases: Challenges and Perspectives
Authors: Pathmanandavel Karrnan , Starling Jean , Dale Russell C. , Brilot Fabienne
Published: August 2013

The pathophysiology of psychosis is poorly understood, with both the cognitive and cellular changes of the disease process remaining mysterious. There is a growing body of evidence that points to dysfunction of the immune system in a subgroup of patients with psychosis. Recently, autoantibodies directed against neuronal cell surface targets have been identified in a range of syndromes that feature psychosis. Of interest is the detection of autoantibodies in patients whose presentations are purely psychiatric, such as those suffering from schizophrenia. Autoantibodies have been identified in a minority of patients, suggesting that antibody-associated mechanisms of psychiatric disease likely only account for a subgroup of cases. Recent work has been based on the application of cell-based assays—a paradigm whose strength lies in the expression of putative antigens in their natural conformation on the surface of live cells. The responsiveness of some of these newly described clinical syndromes to immune therapy supports the hypothesis that antibody-associated mechanisms play a role in the pathogenesis of psychotic disease. However, further investigation is required to establish the scope and significance of antibody pathology in psychosis. The identification of a subgroup of patients with antibody-mediated disease would promise more effective approaches to the treatment of these high-morbidity conditions.
Using Fuzzy Hybrid Features to Classify Strokes in Interactive Sketches
Authors: Wang Shuxia , Wang Guanfeng , Gao Mantun , Yu Suihuai
Published: August 2013

A novel method is presented based on fuzzy hybrid-based features to classify strokes into 2D line drawings, and a human computer interactive system is developed for assisting designers in conceptual design stage. Fuzzy classifiers are built based on some geometric features and speed features. The prototype system can support rapid classification based on fuzzy classifiers, and the classified stroke is then fitted with a 2D geometry primitive which could be a line segment, polyline, circle, circular arc, ellipse, elliptical arc, hyperbola, and parabola. The human computer interaction can determine the ambiguous results and then revise the misrecognitions. The test results showed that the proposed method can support online freehand sketching based on conceptual design with no limitation on drawing sequence and direction while achieving a satisfactory interpretation rate.
Studies on the Food and Feeding Habits of Swamp Deer (Rucervus duvaucelii duvaucelii) in Jhilmil Jheel Conservation Reserve, Haridwar, Uttarakhand, India
Authors: Tewari R. , Rawat G. S.
Published: August 2013

Food habits of the swamp deer (Rucervus duvaucelii duvaucelii) were studied in and around Jhilmil Jheel Conservation Reserve (JJCR), Uttarakhand, for two years. This population (320 in number) was recently rediscovered in the state (2005) and warranted an ecological study because the habitat around this study area is heavily fragmented due to expansion of agriculture, habitation, and various other land use practices. Therefore, this study was initiated by the major objective of studying seasonal variation in food habits of swamp deer. Proportionate food consumption was studied using feeding quadrat method. The study reveals that the overall diet of swamp deer consisted mainly of graminoids (grasses and sedges) and herbs (terrestrial and aquatic). In the protected areas studied earlier, the swamp deer habitat was dominated by grasses, and hence they were reported to be predominantly a grazer who occasionally fed on aquatic plants (Schaller 1967 and others). In contrast, at Jhilmil, the area also has equal presence of other plant types namely, sedges and terrestrial herbs. This resulted in polyphagous feeding habit of animal here.
Personalization of the Workplace through a Proximity Detection System Using User Profiles
Authors: Zato Carolina , Rodríguez Sara , Sánchez Alejandro , Villarrubia Gabriel , Bajo Javier , Corchado Juan Manuel
Published: August 2013

This paper presents a prototype for adapting workplaces for disabled people. The effective integration of people with disabilities in the workplace is a huge challenge to society, and it presents an opportunity to make use of new technologies. The project, called AZTECA, aims to develop new tools that contribute to the employment of groups of people with visual, hearing, or motor disabilities in office environments. These different tools for the disabled people have been modelled with intelligent agents that use Web services. These agents are implemented and deployed within the PANGEA platform so PANGEA conforms the skeleton of the system and allows to develop an integral system. The main target of prototype presented in this work is the people detection using ZigBee technology and the personalization of the workplace according to the user's disability.
Oxidative Stress and Nucleic Acid Oxidation in Patients with Chronic Kidney Disease
Authors: Sung Chih-Chien , Hsu Yu-Chuan , Chen Chun-Chi , Lin Yuh-Feng , Wu Chia-Chao
Published: August 2013

Patients with chronic kidney disease (CKD) have high cardiovascular mortality and morbidity and a high risk for developing malignancy. Excessive oxidative stress is thought to play a major role in elevating these risks by increasing oxidative nucleic acid damage. Oxidative stress results from an imbalance between reactive oxygen/nitrogen species (RONS) production and antioxidant defense mechanisms and can cause vascular and tissue injuries as well as nucleic acid damage in CKD patients. The increased production of RONS, impaired nonenzymatic or enzymatic antioxidant defense mechanisms, and other risk factors including gene polymorphisms, uremic toxins (indoxyl sulfate), deficiency of arylesterase/paraoxonase, hyperhomocysteinemia, dialysis-associated membrane bioincompatibility, and endotoxin in patients with CKD can inhibit normal cell function by damaging cell lipids, arachidonic acid derivatives, carbohydrates, proteins, amino acids, and nucleic acids. Several clinical biomarkers and techniques have been used to detect the antioxidant status and oxidative stress/oxidative nucleic acid damage associated with long-term complications such as inflammation, atherosclerosis, amyloidosis, and malignancy in CKD patients. Antioxidant therapies have been studied to reduce the oxidative stress and nucleic acid oxidation in patients with CKD, including alpha-tocopherol, N-acetylcysteine, ascorbic acid, glutathione, folic acid, bardoxolone methyl, angiotensin-converting enzyme inhibitor, and providing better dialysis strategies. This paper provides an overview of radical production, antioxidant defence, pathogenesis and biomarkers of oxidative stress in patients with CKD, and possible antioxidant therapies.
Hypoxemic Bronchiolitis Related to Major Histocompatibility Class II Deficiency
Authors: Hammami S. , Besbès H. , Hadded S. , Lajmi K. , Ghédira L. , Meriem Ch. B. , Guediche M. N.
Published: August 2013

Major histocompatibility complex class II expression deficiency is an autosomal recessive primary combined immunodeficiency. The prevalence of this deficiency is the highest in Mediterranean areas, especially North Africa. Early diagnosis is essential due to high mortality in the first 2 years of life. Prognosis is very poor when bone marrow transplantation cannot be performed. We report the case of an infant with major histocompatibility complex class II expression deficiency revealed by hypoxemic bronchiolitis due toPneumocystis jiroveci.
Experimental Investigation of the Corrosion Behavior of Friction Stir Welded AZ61A Magnesium Alloy Welds under Salt Spray Corrosion Test and Galvanic Corrosion Test Using Response Surface Methodology
Authors: Dhanapal A. , Boopathy S. Rajendra , Balasubramanian V. , Chidambaram K. , Zaman A. R. Thoheer
Published: August 2013

Extruded Mg alloy plates of 6 mm thick of AZ61A grade were butt welded using advanced welding process and friction stir welding (FSW) processes. The specimens were exposed to salt spray conditions and immersion conditions to characterize their corrosion rates on the effect of pH value, chloride ion concentration, and corrosion time. In addition, an attempt was made to develop an empirical relationship to predict the corrosion rate of FSW welds in salt spray corrosion test and galvanic corrosion test using design of experiments. The corrosion morphology and the pit morphology were analyzed by optical microscopy, and the corrosion products were examined using scanning electron microscope and X-ray diffraction analysis. From this research work, it is found that, in both corrosion tests, the corrosion rate decreases with the increase in pH value, the decrease in chloride ion concentration, and a higher corrosion time. The results show the usage of the magnesium alloy for best environments and suitable applications from the aforementioned conditions. Also, it is found that AZ61A magnesium alloy welds possess low-corrosion rate and higher-corrosion resistance in the galvanic corrosion test than in the salt spray corrosion test.
The Impact of Thermocycling Process on the Dislodgement Force of Different Endodontic Cements
Authors: Saghiri Mohammad Ali , Asatourian Armen , Garcia-Godoy Franklin , Gutmann James L. , Sheibani Nader
Published: August 2013

To evaluate the effects of thermocycling (500 cycles, 5°C/55°C) on the push-out bond strength of calcium silicate based cements including WMTA, Nano-WMTA, and Bioaggregate to root dentin. Forty-eight dentin slices were prepared and divided into 3 groups (n=16) and filled with Angelus WMTA, Nano-WMTA, or Bioaggregate. After incubation, half of the samples were thermocycled while the other half remained untreated. Push-out bond strength was calculated, and the modes of the bond failures were determined by SEM. The highest bond strength was seen in nonthermocycled Nano-WMTA samples and the lowest in thermocycled Bioaggregate samples. The significant differences between nonthermocycled and thermocycled samples were only noticed in WMTA and Nano-WMTA groups (P<0.001). The mode of failure for thermocycled samples of all three cements was mostly cohesive. Thermocycling process can drastically affect the push-out bond strength of calcium silicate based cements. The intrastructural damages occurred due to the thermal stresses, causing cohesive failures in set materials. Sealing property of endodontic cements which have experienced the thermal stresses can be jeopardized due to occlusal forces happening in furcation cites.
Energy‐Efficient Data Gathering Scheme Based on Broadcast Transmissions in Wireless Sensor Networks
Authors: Lee Soobin , Lee Howon
Published: August 2013

Improving energy efficiency is the most important challenge in wireless sensor networks. Because sensing information is correlated in many sensor network applications, some
previous works have proposed ideas that reduce the energy consumption of the network by exploiting the spatial correlation between sensed information. In this paper, we propose a distributed data compression framework that exploits the broadcasting characteristic of the wireless medium to improve energy efficiency. We analyze the performance of the proposed framework numerically and compare it with the performance of previous works using simulation. The proposed scheme performs better when the sensing information is correlated.
Population Abundance of Potentially Pathogenic Organisms in Intestinal Microbiome of Jungle Crow (Corvus macrorhynchos) Shown with 16S rRNA Gene-Based Microbial Community Analysis
Authors: Maeda Isamu , Siddiki Mohammad Shohel Rana , Nozawa-Takeda Tsutomu , Tsukahara Naoki , Tani Yuri , Naito Taki , Sugita Shoei
Published: August 2013

Jungle Crows (Corvus macrorhynchos) prefer human habitats because of their versatility in feeding accompanied with human food consumption. Therefore, it is important from a public health viewpoint to characterize their intestinal microbiota. However, no studies have been involved in molecular characterization of the microbiota based on huge and reliable number of data acquisition. In this study, 16S rRNA gene-based microbial community analysis coupled with the next-generation DNA sequencing techniques was applied to the taxonomic classification of intestinal microbiome for three jungle crows. Clustering of the reads into 130 operational taxonomic units showed that at least 70% of analyzed sequences for each crow were highly homologous toEimeriasp., which belongs to the protozoan phylumApicomplexa. The microbiotas of three crows also contained potentially pathogenic bacteria with significant percentages, such as the generaCampylobacterandBrachyspira. Thus, the profiling of a large number of 16S rRNA gene sequences in crow intestinal microbiomes revealed the high-frequency existence or vestige of potentially pathogenic microorganisms.
Modulation of Vitamin D Status and Dietary Calcium Affects Bone Mineral Density and Mineral Metabolism in Göttingen Minipigs
Authors: Scholz-Ahrens Katharina E. , Glüer Claus-Christian , Bronner Felix , Delling Günter , Açil Yahya , Hahne Hans-Jürgen , Hassenpflug Joachim , Timm Wolfram , Schrezenmeir Jürgen
Published: August 2013

Calcium and vitamin D deficiency impairs bone health and may cause rickets in children and osteomalacia in adults. Large animal models are useful to study experimental osteopathies and associated metabolic changes. We intended to modulate vitamin D status and induce nutritional osteomalacia in minipigs. The control group (n= 9) was fed a semisynthetic reference diet with 6 g calcium and 6,500 IU vitamin D3/kg and the experimental group (n= 10) the same diet but with only 2 g calcium/kg and without vitamin D. After 15 months, the deficient animals were in negative calcium balance, having lost bone mineral density significantly (means ± SEM) with −51.2 ± 14.7 mg/cm3in contrast to controls (−2.3 ± 11.8 mg/cm3), whose calcium balance remained positive. Their osteoid surface was significantly higher, typical of osteomalacia. Their plasma 25(OH)D dropped significantly from 60.1 ± 11.4 nmol/L to 15.3 ± 3.4 nmol/L within 10 months, whereas that of the control group on the reference diet rose. Urinary phosphorus excretion and plasma 1,25-dihydroxyvitamin D concentrations were significantly higher and final plasma calcium significantly lower than in controls. We conclude that the minipig is a promising large animal model to induce nutritional osteomalacia and to study the time course of hypovitaminosis D and associated functional effects.
Primary Mesenteric Smooth Muscle Tumor: An Entity with Unpredictable Biologic Behavior
Authors: Kalogiannidis Ioannis , Stavrakis Thomas , Amplianitis Ioannis , Grammenou Sophia , Mavromatidis Georgios , Rousso David
Published: August 2013

Smooth muscle tumors of the mesentery are rare lesions with unpredictable, usually malignant, biologic behavior irrespective of their histologic appearance. Such case is presented here. We present a case of a large smooth muscle tumor located in the mesentery of a 48 years old patient. The histopathologic features of the surgically excised tumor were that of a benign-appearing smooth muscle tumor, either a primary mesenteric smooth muscle tumor of unknown biologic behavior or a parasitic leiomyoma. The patient was discharged 4 days after from the hospital without any early postoperative complication. Close followup was further decided. Nine months after her primary therapy, our patient is alive and with no evidence of recurrent disease. Increased awareness must be considered for large mesenteric smooth muscle tumors, because even when they present indolent histologic features, they usually behave aggressively.
Propofol Protects against Ischemia/Reperfusion Injury Associated with Reduced Apoptosis in Rat Liver
Authors: Abdel-Wahab Ali F. , Al-Harizy Wahid M.
Published: August 2013

Propofol is an intravenous anesthetic, reported to have a protective effect against ischemia/reperfusion (I/R) injury in heart and brain, but no definite data are available concerning its effect in hepatic I/R. This work investigated the effect of propofol anesthesia on hepatic I/R injury using in vivo rat model. Four groups of rats were included: sham operated, I/R (30 min ischemia and 2 h reperfusion), I/R treated with propofol (10 mg/kg/h), and I/R treated with propofol (20 mg/kg/h). Liver enzyme leakage, TNF-α and caspase-3 levels, and antiapoptotic Bcl-xL/apoptotic Bax gene expression, together with histopathological changes, were used to evaluate the extent of hepatic I/R injury. Compared with sham-operated group, I/R group showed significant increase in serum levels of liver enzymes (ALT, AST), TNF-α, and caspase-3 and significant decrease in the Bcl-xL/Bax ratio, associated with histopathologic damage in liver. Propofol infusion significantly attenuated these changes with reduced hepatic histopathologic lesions compared with nonpreconditioned I/R group. However, no significant differences were found between two groups treated with different doses of propofol. In conclusion, propofol infusion reduced hepatic I/R injury with decreased markers of cellular apoptosis. Therefore, propofol anesthesia may provide a useful hepatic protection during liver surgery.
Identification of Antioxidants from Sequence Information Using Naïve Bayes
Authors: Feng Peng-Mian , Lin Hao , Chen Wei
Published: August 2013

Antioxidant proteins are substances that protect cells from the damage caused by free radicals. Accurate identification of new antioxidant proteins is important in understanding their roles in delaying aging. Therefore, it is highly desirable to develop computational methods to identify antioxidant proteins. In this study, a Naïve Bayes-based method was proposed to predict antioxidant proteins using amino acid compositions and dipeptide compositions. In order to remove redundant information, a novel feature selection technique was employed to single out optimized features. In the jackknife test, the proposed method achieved an accuracy of 66.88% for the discrimination between antioxidant and nonantioxidant proteins, which is superior to that of other state-of-the-art classifiers. These results suggest that the proposed method could be an effective and promising high-throughput method for antioxidant protein identification.
Denervation as a Common Mechanism Underlying Different Pulmonary Vein Isolation Strategies for Paroxysmal Atrial Fibrillation: Evidenced by Heart Rate Variability after Ablation
Authors: Wang Kejing , Chang Dong , Chu Zhenliang , Yang Yanzong , Gao Lianjun , Zhang Shulong , Xia Yunlong , Dong Yingxue , Yin Xiaomeng , Cong Peixin , Jia Jingjing
Published: August 2013

Backgrounds. Segmental and circumferential pulmonary vein isolations (SPVI and CPVI) have been demonstrated to be effective therapies for paroxysmal atrial fibrillation (PAF). PVI is well established as the endpoint of different ablation techniques, whereas it may not completely account for the long‐term success. Methods. 181 drug‐refractory symptomatic PAF patients were referred for segmental or circumferential PVI (SPVI = 67; CPVI = 114). Heart rate variability (HRV) was assessed before and after the final ablation. Results. After following up for 62.23 ± 12.75 months, patients underwent 1.41 ± 0.68 procedures in average, and the success rates in SPVI and CPVI groups were comparable. 119 patients were free from AF recurrence (SPVI‐S, n = 43; CPVI‐S, n = 76). 56 patients had recurrent episodes (SPVI‐R, n = 21; CPVI‐R, n = 35). Either ablation technique decreased HRV significantly. Postablation SDNN and rMSSD were significantly lower in SPVI‐S and CPVI‐S subgroups than in SPVI‐R and CPVI‐R subgroups (SPVI‐S versus SPVI‐R: SDNN 91.8 ± 32.6 versus 111.5 ± 36.2 ms, rMSSD 47.4 ± 32.3 versus 55.2 ± 35.2 ms; CPVI‐S versus CPVI‐R: SDNN 83.0 ± 35.6 versus 101.0 ± 40.7 ms, rMSSD 41.1 ± 22.9 versus 59.2 ± 44.8 ms; all P < 0.05). Attenuation of SDNN and rMSSD remained for 12 months in SPVI‐S and CPVI‐S subgroups, whereas it recovered earlier in SPVI‐R and CPVI‐R subgroups. Multivariate logistic regression analysis identified SDNN as the only predictor of long‐term success. Conclusions. Beyond PVI, denervation may be a common mechanism underlying different ablation strategies for PAF.
Synergistic Action of Flavonoids, Baicalein, and Daidzein in Estrogenic and Neuroprotective Effects: A Development of Potential Health Products and Therapeutic Drugs against Alzheimer’s Disease
Authors: Choi Roy C. Y. , Zhu Judy T. T. , Yung Amanda W. Y. , Lee Pinky S. C. , Xu Sherry L. , Guo Ava J. Y. , Zhu Kevin Y. , Dong Tina T. X. , Tsim Karl W. K.
Published: August 2013

Despite the classical hormonal effect, estrogen has been reported to mediate neuroprotection in the brain, which leads to the searching of estrogen-like substances for treating neurodegenerative diseases. Flavonoids, a group of natural compounds, are well known to possess estrogenic effects and used to substitute estrogen, that is, phytoestrogen. Flavonoid serves as one of the potential targets for the development of natural supplements and therapeutic drugs against different diseases. The neuroprotection activity of flavonoids was chosen for a possible development of anti-Alzheimer's drugs or food supplements. The estrogenic activity of two flavonoids, baicalein and daidzein, were demonstrated by their strong abilities in stimulating estrogen receptor phosphorylation and transcriptional activation of estrogen responsive element in MCF-7 breast cells. The neuroprotection effects of flavonoids againstβ-amyloid (Aβ) were revealed by their inhibition effects onin vitroAβaggregation and Aβ-induced cytotoxicity in PC12 neuronal cells. More importantly, the estrogenic and neuroprotective activities of individual flavonoid could be further enhanced by the cotreatment in the cultures. Taken together, this synergistic effect of baicalein and daidzein might serve as a method to improve the therapeutic efficacy of different flavonoids against Aβ, which might be crucial in developing those flavonoidsin treating Alzheimer's disease in the future.
Structure-Based Virtual Screening and Molecular Dynamic Simulation Studies to Identify Novel Cytochrome bc1 Inhibitors as Antimalarial Agents
Authors: Gangwal Rahul P. , Dhoke Gaurao V. , Damre Mangesh V. , Khandelwal Kanchan , Sangamwar Abhay T.
Published: August 2013

Cytochrome bc1 (EC 1.10.2.2, bc1) is an essential component of the cellular respiratory chain, which catalyzes electron transfer from quinol to cytochrome c and concomitantly the translocation of protons across the membrane. It has been identified as a promising target in malaria parasites. The structure-based pharmacophore modelling and molecular dynamic simulation approach have been employed to identify novel inhibitors of cytochrome bc1. The best structure-based pharmacophore hypothesis (Hypo1) consists of one hydrogen bond acceptor (HBA), one general hydrophobic (HY), and two hydrophobic aromatic features (HYAr). Further, hydrogen interactions and hydrophobic interactions of known potent inhibitors with cytochrome bc1 were compared with Hypo1, which showed that the Hypo1 has good predictive ability. The validated Hypo1 was used to screen the chemical databases. The hits obtained were subsequently subjected to the molecular docking analysis to identify false-positive hits. Moreover, the molecular docking results were further validated by molecular dynamics simulations. Binding-free energy analysis using MM-GBSA method reveals that the van der Waals interactions and the electrostatic energy provide the basis for favorable absolute free energy of the complex. The five virtual hits were identified as possible candidates for the designing of potent cytochrome bc1 inhibitors.
A Network Study of Chinese Medicine Xuesaitong Injection to Elucidate a Complex Mode of Action with Multicompound, Multitarget, and Multipathway
Authors: Wang Linli , Li Zheng , Zhao Xiaoping , Liu Wei , Liu Yufeng , Yang Jihong , Li Xiang , Fan Xiaohui , Cheng Yiyu
Published: August 2013

Chinese medicine has evolved from thousands of years of empirical applications and experiences of combating diseases. It has become widely recognized that the Chinese medicine acts through complex mechanisms featured as multicompound, multitarget and multipathway. However, there is still a lack of systematic experimental studies to elucidate the mechanisms of Chinese medicine. In this study, the differentially expressed genes (DEGs) were identified from myocardial infarction rat model treated with Xuesaitong Injection (XST), a Chinese medicine consisting of the total saponins fromPanax notoginseng(Burk.) F. H. Chen (Chinese Sanqi). A network-based approach was developed to combine DEGs related to cardiovascular diseases (CVD) with lines of evidence from the literature mining to investigate the mechanism of action (MOA) of XST on antimyocardial infarction. A compound-target-pathway network of XST was constructed by connecting compounds to DEGs validated with literature lines of evidence and the pathways that are functionally enriched. Seventy potential targets of XST were identified in this study, of which 32 were experimentally validated either by ourin vitroassays or by CVD-related literatures. This study provided for the first time a network view on the complex MOA of antimyocardial infarction through multiple targets and pathways.
An Inventory Model with Finite Replenishment Rate, Trade Credit Policy and Price-Discount Offer
Authors: Sarkar Biswajit , Sana Shib Sankar , Chaudhuri Kripasindhu
Published: August 2013

When some suppliers offer trade credit periods and price discounts to retailers in order to increase the demand of their products, retailers have to face different types of discount offers and credits within which they have to take a decision which is the best offer for them to make more profit. The retailers try to buy perfect-quality items at a reasonable price, and also they try to invest returns obtained by selling those items in such a manner that their business is not hampered. In this point of view, we consider an economic order quantity (EOQ) model for various types of time-dependent demand when delay in payment and price discount are permitted by suppliers to retailers. The models of various demand patterns are discussed analytically. Some numerical examples and graphical representations are considered to illustrate the model.
Phase Transitions of Contingent Planning Problem
Authors: Zhou Junping , Su Weihua , Ma Zhiqiang , Yin Minghao
Published: August 2013

This paper explores the phase transitions of the contingent planning problems. We present CONTINGENT PLAN-EXISTENCE algorithm and CONTINGENT PLAN-NONEXISTENCE algorithm for quickly proving that the contingent planning instances have solutions and have no solutions, respectively. By analyzing the two algorithms, the phase transition area of the contingent planning problems is obtained. If the number of the actions is not greater thanθub, the CONTINGENT PLAN-NONEXISTENCE algorithm can prove that nearly all the contingent planning instances have no solution. If the number of the actions is not lower thanθlb, the CONTINGENT PLAN-EXISTENCE algorithm can prove that nearly all the contingent planning instances have solutions. The results of the experiments show that there exist phase transitions from a region where almost all the contingent planning instances have no solution to a region where almost all the contingent planning instances have solutions.