bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydration status and fluid and sodium balance in elite Canadian junior women’s soccer players in a cool environment
Authors: Gibson Jennifer C. , Stuart-Hill Lynneth A. , Pethick Wendy , Gaul Catherine A.
Published: August 2012

Dehydration can impair mental and on-field performance in soccer athletes; however, there is little data available from the female adolescent player. There is a lack of research investigating fluid and electrolyte losses in cool temperatures. Therefore, the purpose of this study was to investigate the pretraining hydration status, fluid balance, and sweat sodium loss in 34 female Canadian junior elite soccer athletes (mean age ± SD, 15.7 ± 0.7 years) in a cool environment. Data were collected during two 90 min on-field training sessions (9.8 ± 3.3 °C, 63% ± 12% relative humidity). Prepractice urine specific gravity (USG), sweat loss (pre- and post-training body mass), and sweat sodium concentration (regional sweat patch method) were measured at each session. Paired t tests were used to identify significant differences between training sessions and Pearson’s product moment correlation analysis was used to assess any relationships between selected variables (p ≤ 0.05). We found that 45% of players presented to practice in a hypohydrated state (USG > 1.020). Mean percent body mass loss was 0.84% ± 0.07% and sweat loss was 0.69 ± 0.54 L. Although available during each training session, fluid intake was low (63.6% of players consumed <250 mL). Mean sweat sodium concentration was 48 ± 12 mmol·L–1. Despite low sweat and moderate sodium losses, players did not drink enough to avoid mild fluid and sodium deficits during training. The findings from this study highlights the individual variations that occur in hydration management in athletes and thus the need for personalized hydration guidelines.
SEMANTIC E-INK: KNOWLEDGE-BASED ASSISTANCE FOR MAKING MENTAL MODELS EXPLICIT
Authors: DENGEL ANDREAS , LIWICKI MARCUS
Published: August 2012

In this paper we describe a system which assists knowledge workers in making notes of their thoughts and transferring them to the computer. Our system processes handwritten notes written down with a digital pen. These notes are processed in order to recognize and understand their meaning. To realize such systems, two novel processing stages are proposed for the first time in literature. The first stage is the inclusion of knowledge bases into the Handwriting Recognition (HWR) process, where we make use of a person's mental model. The second stage is the transition from pure HWR to understanding of the handwritten notes, i.e. the system extracts knowledge in form of ontologies. For both novel approaches we performed a set of experiments on various data. With the proposed techniques, the recognition rate of the HWR system as well as the performance of the information extraction system are significantly increased.
THE CRITICAL VALUES OF RANKIN–SELBERG CONVOLUTIONS
Authors: KASTEN HENDRIK , SCHMIDT CLAUS-GÜNTHER
Published: August 2012

For a pair (π, σ) of cuspidal automorphic representations of GL n and GL n-1, both of non-vanishing cohomology, we show algebraicity properties of critical values of the associated Rankin–Selberg L-function twisted by finite-order characters. A certain non-vanishing assumption about the associated archimedean Rankin–Selberg pairings on the cohomology is established for n = 3.
ON THE DIVISORS OF xn – 1 IN 𝔽p[x]
Authors: THOMPSON LOLA
Published: August 2012

In a recent paper, we considered integers n for which the polynomial xn – 1 has a divisor in ℤ[x] of every degree up to n, and we gave upper and lower bounds for their distribution. In this paper, we consider those n for which the polynomial xn – 1 has a divisor in 𝔽p[x] of every degree up to n, where p is a rational prime. Assuming the validity of the Generalized Riemann Hypothesis, we show that such integers n have asymptotic density 0.
ON THE MEAN VALUE OF THE INDEX OF COMPOSITION OF AN INTEGER II
Authors: ZHANG DEYU , LÜ MEIMEI , ZHAI WENGUANG
Published: August 2012

For each integer n ≥ 2, let [Formula: see text] be the index of composition of n, where γ(n) ≔ ∏p∣np. The index of composition of an integer measures the multiplicity of its prime factors. In this paper, we obtain a new asymptotic formula of the sum ∑n≤xλ-k(n). Furthermore, we improve the error term under the Riemann Hypothesis.
Inhibition of Copper Pitting Corrosion in Aggressive Potable Waters
Authors: Sarver Emily , Edwards Marc
Published: August 2012

Copper pitting corrosion can lead to premature plumbing failures, and can be caused by aggressive potable waters characterized by high pH, free chlorine residual and low alkalinity. In such waters and under continuous flow, certain inhibitors including phosphate, silica or natural organic matter may greatly reduce pitting occurrence. In the current work, 1 mg/L phosphate (as P) completely prevented initiation of pits, and 5 mg/L silica (as Si) significantly decelerated pitting. However, much lower doses of these inhibitors had little benefit and actually accelerated the rate of attack in some cases. Effects of organic matter were dependent on both the type (e.g., natural versus ozonated humic substances) and dosage. Dose-response effects of free chlorine and alkalinity were also investigated. Based on electrochemical data, pits initiated more rapidly with increased free chlorine, but even moderate levels of chlorine (~0.4 mg/L) eventually caused severe pitting. High alkalinity decreased pit propagation rates but did not prevent pit formation.
Apolipoprotein E Enhances Endothelial-NO Production by Modulating Caveolin 1 Interaction With Endothelial NO Synthase
Authors: Yue Lili , Bian Jing-Tan , Grizelj Ivana , Cavka Ana , Phillips Shane A. , Makino Ayako , Mazzone Theodore
Published: August 2012

Apolipoprotein E (apoE) is widely expressed in mammalian tissues, and one of the important tissue-specific effects is the atheroprotection ascribed to macrophage-derived apoE in the arterial wall. However, underlying mechanisms are not well understood. In this study, using subcellular fractionation, confocal microscopy, and coimmunoprecipitation, we demonstrated that macrophage-derived apoE is internalized by endothelial cells and impacts the subcellular distribution/interaction of caveolin 1 (cav-1) and endothelial NO synthase (eNOS). The addition of apoE disrupts the heteromeric complex formed between cav-1 and eNOS, and increases NO production. Sterol and oxysterol enhance endothelial cav-1/eNOS interaction and suppress NO production, but these effects are reversed by apoE. Silencing endothelial cav-1 attenuates apoE-induced NO production, establishing the importance of the cav-1-eNOS interaction for the increment in endothelial NO produced by apoE. Consistent with these observations, macrophage-derived apoE significantly improves vasodilation to acetylcholine in resistance arteries isolated from adipose tissue of obese humans. We conclude that macrophage-derived apoE enhances endothelial NO production by disrupting the inhibitory interaction of eNOS with cav-1. These results establish a novel mechanism by which apoE modulates endothelial cell function.
An Estimate of the Lorenz Energy Cycle for the World Ocean Based on the STORM/NCEP Simulation
Authors: Storch Jin-Song von , Eden Carsten , Fast Irina , Haak Helmuth , Hernández-Deckers Daniel , Maier-Reimer Ernst , Marotzke Jochem , Stammer Detlef
Published: August 2012

This paper presents an estimate of the oceanic Lorenz energy cycle derived from a simulation forced by 6-hourly fluxes obtained from NCEP–NCAR reanalysis-1. The total rate of energy generation amounts to 6.6 TW, of which 1.9 TW is generated by the time-mean winds and 2.2 TW by the time-varying winds. The dissipation of kinetic energy amounts to 4.4 TW, of which 3 TW originate from the dissipation of eddy kinetic energy. The energy exchange between reservoirs is dominated by the baroclinic pathway and the pathway that distributes the energy generated by the time-mean winds. The former converts 0.7 to 0.8 TW mean available potential energy to eddy available potential energy and finally to eddy kinetic energy, whereas the latter converts 0.5 TW mean kinetic energy to mean available potential energy.

This energy cycle differs from the atmospheric one in two aspects. First, the generation of the mean kinetic and mean available potential energy is each, to a first approximation, balanced by the dissipation. The interaction of the oceanic general circulation with mesoscale eddies is hence less crucial than the corresponding interaction in the atmosphere. Second, the baroclinic pathway in the ocean is facilitated not only by the surface buoyancy flux but also by the winds through a conversion of 0.5 TW mean kinetic energy to mean available potential energy. In the atmosphere, the respective conversion is almost absent and the baroclinic energy pathway is driven solely by the differential heating.
Differences in signaling through the B-cell leukemia oncoprotein CRLF2 in response to TSLP and through mutant JAK2
Authors: van Bodegom Diederik , Zhong Jun , Kopp Nadja , Dutta Chaitali , Kim Min-Sik , Bird Liat , Weigert Oliver , Tyner Jeffrey , Pandey Akhilesh , Yoda Akinori , Weinstock David M.
Published: August 2012

Approximately 10% of B-cell acute lymphoblastic leukemias (B-ALLs) overexpress the cytokine receptor subunit CRLF2, which may confer a poor prognosis. CRLF2 binds its ligand thymic stromal lymphopoietin (TSLP) as a heterodimer with IL7R. Subsets of CRLF2-overexpressing B-ALLs also have a gain-of-function CRLF2 F232C mutation or activating mutations in JAK2. Whether these mutant alleles confer differences in signaling has not been addressed. Through a domain mutation analysis, we demonstrate a distinct dependence on the CRLF2 intracellular tyrosine Y368 in signaling by CRLF2 F232C, but not signaling induced by TSLP or through CRLF2/mutant JAK2. In contrast, CRLF2 signaling in each context is strictly dependent on both the CRLF2 box1 domain and the intracellular tryptophan W286. Using a global quantitative analysis of tyrosine phosphorylation induced by TSLP, we previously identified TSLP-induced phosphorylation of multiple kinases implicated in B-cell receptor signaling, including Lyn, Btk, Hck, Syk, MAPK8, MAPK9, and MAPK10. We now demonstrate that cells dependent on CRLF2/mutant JAK2 have reduced phosphorylation at these targets, suggesting that the kinases promote TSLP-mediated proliferation but serve as negative regulators of CRLF2/mutant JAK2 signaling. Thus, targetable nodes downstream of CRLF2 differ based on the presence or absence of additional mutations in CRLF2 signaling components.
Characterization of bovine FUT7 furthers understanding of FUT7 evolution in mammals
Authors: Laporte Benoît , Petit Daniel , Rocha Dominique , Boussaha Mekki , Grohs Cécile , Maftah Abderrahman , Petit Jean-Michel
Published: August 2012

Background

The Sialyl-Lewis X (Slex) is a well-known glycan structure involved in leukocyte homing and recruitment to inflammatory sites. SLex is well conserved among species and is mainly synthesized by FucT-VII in vertebrates. The enzyme responsible for its biosynthesis in cattle was not known.

Results

We cloned a cDNA sequence encoding bovine α3-fucosyltransferase VII that shares 83% identity with its human counterpart. Located at the BTA 11 telomeric region, the 1029 bp open reading frame is spread over two different exons, E1 which also contains the unique 5’-untranslated region and E2 which includes the entire 3’-untranslated region. The bfut7 expression pattern is restricted to thymus and spleen. A single transcript leading to the synthesis of a 342 aa protein was identified. The encoded fucosyltransferase, produced as a recombinant enzyme in COS-1 cells, was shown to be specifically responsible for SLex synthesis in cattle. In addition, we showed that the gene promoter evolved from fish to mammals towards a complex system related to the immune system. But beyond the fact that the gene regulation seems to be conserved among mammals, we also identified 7 SNPs including 3 missense mutations in the coding region in a small panel of animals.

Conclusions

The FUT7 sequence was highly conserved as well as the specific activity of the encoded protein FucT-VII. In addition, our in silico promoter analysis and the high rate of polymorphism suggested that its function is evolving toward a complex system related to the immune system. Furthermore, comparing bovine to human and mouse sequences, it appeared that a decrease in gene regulation was correlated with an increase in mutation rate and wider tissue expression.
Kinetic Study of the Absorption of Carbon Dioxide by Aqueous Triethanolamine Solutions
Authors: La Rubia M. Dolores , Pacheco Rafael , Sánchez Antonio , López García Ana Belén , Sánchez Sebastián , Camacho Fernando
Published: August 2012

In this work, the absorption of pure carbon dioxide by aqueous triethanolamine solutions (TEA) was studied in terms of the kinetic process. The process was made in a stirred tank reactor with a flat and known interfacial area, the operating variables being temperature (288 to 313 K) and concentration in the range 0.1-2.0 M. From the results, it was deduced that the absorption of pure carbon dioxide by aqueous triethanolamine takes place under isothermal conditions in which there is an instantaneous reaction regime at low concentrations, while at higher concentrations it takes place in a moderately fast reaction regime, following a first-order kinetic with respect to alkanolamine. In these conditions of concentrations and temperatures essayed, an expression for the constant kinetic was deduced.
Exploring synergies between academia and vaccine manufacturers: a pilot study on how to rapidly produce vaccines to combat emerging pathogens
Authors: Strecker Thomas , Uhlendorff Jennifer , Diederich Sandra , Lenz-Bauer Claudia , Trusheim Heidi , Roth Bernhard , Kolesnikova Larissa , Aepinus Christian , Dornow Reiner , Gerlach Jens , Matrosovich Mikhail , Valley Ulrich , Eickmann Markus , Becker Stephan
Published: August 2012

Background: In spring 2009, a new swine-origin influenza A (H1N1) virus emerged in Mexico. During the following weeks the virus spread worldwide, prompting the World Health Organization to declare the first influenza pandemic of the 21st century. Sustained human-to-human transmission and severe disease progression observed in some patients urged public health authorities to respond rapidly to the disease outbreak and vaccine manufacturers to develop pandemic influenza vaccines for mass distribution. With the onset of the pandemic we began to explore the potential of academic/industrial collaboration to accelerate the production of vaccines during an outbreak of an emerging virus by combining the use of an academic BSL-4 laboratory with the expertise of a commercial vaccine manufacturer.

Methods and results: To obtain virus seed stocks used for the production of a vaccine to combat the pandemic H1N1 2009 influenza virus (H1N1pdm), we followed various strategies: (i) optimization of cell culture conditions for growth of wild-type H1N1pdm isolates; (ii) classical reassortment of H1N1pdm and standard influenza vaccine donor strain PR8; and (iii) generation of corresponding reassortant viruses using reverse genetics. To ensure a rapid transition to production, the entire potential seed stock development process was carried out in a certified canine kidney suspension cell line (MDCK 33016-PF) under Good Manufacturing Practice (GMP) conditions.

Conclusions: The outcome of this study indicates that a combination of different experimental strategies is the best way to cope with the need to develop vaccines rapidly in the midst of an emerging pandemic.
Translating exome sequencing from research to clinical diagnostics
Authors: Coonrod Emily M. , Margraf Rebecca L. , Voelkerding Karl V.
Published: August 2012

In the relatively short time frame since the introduction of next generation sequencing, it has become a method of choice for complex genomic research studies. As a paradigm shifting technology, we are now witnessing its translation into clinical diagnostic laboratories for patient care. Multi-gene panels for a variety of disorders are now available in several clinical laboratories based on targeted gene enrichment followed by next generation sequencing. Genome wide interrogation of protein coding regions, or exome sequencing, has been successfully and increasingly applied in the research setting for the elucidation of candidate genes and causal variants in individuals and families with a diversity of rare and complex genetic disorders. Based on this progress, exome sequencing is also beginning a translational process into clinical practice. However, introducing exome sequencing as a diagnostic modality poses new technical and bioinformatics challenges for clinical laboratories. In this review, we present technical and bioinformatics aspects of exome sequencing, describe representative examples from the literature of how exome sequencing has been used for candidate gene discovery, and discuss considerations for its clinical translation.
IFCC standardised HbA1c: should the world be as one?
Authors: John Garry , English Emma
Published: August 2012

The central importance of HbA1c in monitoring glycaemic control was highlighted by the Diabetes Control and Complications Trial (DCCT) which showed that improved glycaemic control, as monitored by HbA1c, delayed the onset of diabetic complications. Following this publication the issue of international standardisation of glycated haemoglobin (GHb) measurements became an important objective. The lack of international standardisation resulted in several countries developing National Standardisation Programmes. The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) Working Group on HbA1cStandardisation has established a reference measurement procedure (HPLC-MS or HPLC-CE) for HbA1c embracing the concept of metrological traceability. The reference method is anchored to a global network of 15 approved reference laboratories; this confers sustainability and a low level of uncertainty. Essential elements of a comprehensive reference measurement system additionally include the definition of the measurand and the unit of measurement. HbA1c is defined as haemoglobin (Hb) molecules having a stable adduct of glucose to the N-terminal valine of the β chain [Hb β chain (Blood) – N-(1-deoxyfructos-1-yl) Hb β chain] and that mmol/mol be used as the unit of measurement. These developments will result in improvements in inter-method and inter-laboratory agreement. Additionally, global acceptance of standardisation based on metrologically sound principles will enable clinical goals and diagnostic guidelines to be developed that can be adopted by all countries.
Suitability of POC lactate methods for fetal and perinatal lactate testing: considerations for accuracy, specificity and decision making criteria
Authors: Orsonneau Jean-Luc , Fraissinet François , Sébille-Rivain Véronique , Dudouet Daniele , Bigot-Corbel Edith
Published: August 2012

Background: Point of care (POC) testing for fetal scalp blood lactate is a more user friendly and more successful approach compared to scalp pH for intrapartum fetal monitoring. The aim of this study was to assess the analytical specificity and clinical reliability of three POC lactate methods.

Methods: The analytical performance of three POC lactate methods was compared to Cobas 6000 (Roche Diagnostics) laboratory reference method: Lactate Pro from Arkray, GEM 4000 from Instrumentation Laboratory and StatStrip Lactate from Nova Biomedical. The clinical performance and influences on accuracy and decision making criteria for the three POC methods was assessed with umbilical cord samples and compared to the laboratory reference method. The influence of varying ranges of hemoglobin, pH and partial oxygen pressure (pO2) on the accuracy of results was assessed.

Results: Although all three POC methods showed good correlation with the reference method for the umbilical cord sample population (r=0.989, 0.973 and 0.980, respectively), Lactate Pro and Gem 4000 showed a significant negative bias compared to the reference method. The degree of bias meant a significant readjustment of decision making criteria was required for fetal lactate use. The accuracy of the Lactate Pro results was affected by hemoglobin and to a lesser extent pH.

Conclusions: The three electrochemical POC devices can measure fetal lactate reliably. StatStrip Lactate showed a closer correlation and concordance to our laboratory reference method. The results of this study indicate the requirement for predetermining the reliability of POC lactate methods before use present in fetal and perinatal settings.
Applications of a transcendence criterion for reciprocal sums of binary linear recurrences
Authors: Kurosawa Takeshi
Published: August 2012

Let {R

n
}
n≥0 be a binary recurrence defined by
R

n+2 = A
R

n+1 + B
Rn
(n ≥ 0), where
A, B, R
0, R
1 are integers and
Δ = A
2 + 4B > 0 is not a perfect square.
We show a necessary and sufficient condition for the transcendency of the sum

∑

k
≥
0
,

R

r
k

≠
-

b
k

a
k

R

r
k

+

b
k

,

$
{\sum _{k\ge 0, {R_{r^k}\ne -b_k}}\frac{a_k}{R_{r^k}+b_k}},
$

where r ≥ 2 is an integer
and {a

k
}
k≥0 and {b

k
}
k≥0 are sequences of algebraic numbers satisfying
certain growth conditions. For the proof, we apply the transcendence criterion for Mahler type
functions of several variables which gives equivalence between the rationality of the function
and the algebraicity of its values at algebraic points.
Influence of hygromechanical history on the longitudinal mechanosorptive creep of wood
Authors: Montero Cédric , Gril Joseph , Legeas Clémentine , Hunt David G. , Clair Bruno
Published: August 2012

An experiment was performed on Norway spruce to simplify our understanding of mechanosorptive creep. Two well-matched sets of specimens were subjected to the same humidity history but loaded in four-point bending at different times. One set was loaded dry, and thus experienced a considerable creep at first adsorption (the so-called ++ effect). The other set was then loaded wet and only exhibited, together with the dry-loaded set, the usual pattern of creep increase during drying (- effect) followed by a partial recovery during remoistening (+ effect). Both sets converged to the same response after a few cycles. The results confirm that a single type of mechanosorption, combined with strain-dependent hygroexpansion and humidity-dependent viscoelascity, is sufficient to account for all observed features of longitudinal creep of wood at ambient temperature.
Distribution of extracts including 4,8-dihydroxy-5-methoxy-2-naphthaldehyde in Diospyros kaki analyzed by gas chromatography-mass spectrometry and time-of-flight secondary ion mass spectrometry
Authors: Matsushita Yasuyuki , Jang In-Cheol , Imai Takanori , Takama Ruka , Saito Kaori , Masumi Takashi , Lee Seung-Cheol , Fukushima Kazuhiko
Published: August 2012

The distribution of ethyl acetate extracts and 4,8-dihydroxy-5-methoxy-2-naphthaldehyde (compound I), which is a major constituent of the extracts obtained from the blackened heartwood of Diospyros kaki, was analyzed via gas chromatography-mass spectrometry (GC-MS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS). According to GC-MS, the extracts and compound I are high in concentration at the pith and at the edges of the blackened heartwood. ToF-SIMS analysis revealed a peak at a mass-to-charge ratio of (m/z) 218, which is characteristic of the ionic form of compound I. The ToF-SIMS imaging of compound I in the blackened heartwood based on m/z 218 shows that compound I is located in parenchyma cells and their neighboring axial elements.
Testing of the superhydrophobicity of a zinc oxide nanorod array coating on wood surface prepared by hydrothermal treatment
Authors: Fu Yanchun , Yu Haipeng , Sun Qingfeng , Li Gang , Liu Yongzhuang
Published: August 2012

Natural wood surface is hydrophilic and can easily absorb moisture. Inorganic nanometer-scale metal oxides can be controlled and fabricated on wood surface to serve as a protective coating. In the present study, a superhydrophobic surface consisting of zinc oxide (ZnO) nanorod array was successfully attached on wood via a cosolvent hydrothermal method at low temperature. By means of X-ray diffraction pattern and Fourier transform infrared spectroscopy, the presence of the hexagonal wurtzite phase of ZnO was detected and characterized. Field-emission scanning electron microscopy showed uniform, large-scale rod-like ZnO crystal whiskers on the wood surface. The wettability of the wood surface after treatment became superhydrophobic, with a water contact angle of 153°. The prepared coating also showed an anti-contamination effect against milk, cola, soya sauces and coffee.
Functional characterization of the Mycobacterium tuberculosis zinc metallopeptidase Zmp1 and identification of potential substrates
Authors: Petrera Agnese , Amstutz Beat , Gioia Magda , Hähnlein Janine , Baici Antonio , Selchow Petra , Ferraris Davide M. , Rizzi Menico , Sbardella Diego , Marini Stefano , Coletta Massimo , Sander Peter
Published: August 2012

Zinc metallopeptidases of bacterial pathogens are widely distributed virulence factors and represent promising pharmacological targets. In this work, we have characterized Zmp1, a zinc metallopeptidase identified as a virulence factor of Mycobacterium tuberculosis and belonging to the neprilysin (NEP; M13) family, whose X-ray structure has been recently solved. Interestingly, this enzyme shows an optimum activity toward a fluorogenic substrate at moderately acidic pH values (i.e., 6.3), which corresponds to those reported for the Mtb phagosome where this enzyme should exert its pathological activity. Substrate specificity of Zmp1 was investigated by screening a peptide library. Several sequences derived from biologically relevant proteins were identified as possible substrates, including the neuropeptides bradykinin, neurotensin, and neuropeptide FF. Further, subsequences of other small bioactive peptides were found among most frequently cleaved sites, e.g., apelin-13 and substance P. We determined the specific cleavage site within neuropeptides by mass spectrometry, observing that hydrophobic amino acids, mainly phenylalanine and isoleucine, are overrepresented at position P1′. In addition, the enzymatic mechanism of Zmp1 toward these neuropeptides has been characterized, displaying some differences with respect to the synthetic fluorogenic substrate and indicating that the enzyme adapts its enzymatic action to different substrates.
Platelet function and thymosin β4
Authors: Kaur Harmanpreet , Mutus Bulent
Published: August 2012

Thymosin β4 (Tβ4) is a small, low-molecular-weight peptide ubiquitously expressed in all cells and extracellular fluids. It is a major actin sequestering protein present in the cells. In addition to this, Tβ4 has also been shown to be involved in endothelial cell migration, angiogenesis, corneal wound healing, and stem cell differentiation. It is also released by platelets after activation. The amount of Tβ4 increases at sites of injury and thus suggests an important role of this biopeptide in wound healing. Herein, we provide an overview of the role of Tβ4 in thrombosis and platelet aggregation.
A catalogue of putative HIV-1 protease host cell substrates
Authors: Impens Francis , Timmerman Evy , Staes An , Moens Kathleen , Ariën Kevin K. , Verhasselt Bruno , Vandekerckhove Joël , Gevaert Kris
Published: August 2012

Processing of human immunodeficiency virus (HIV) proteins by the HIV-1 protease is essential for HIV infectivity. In addition, several studies have revealed cleavage of human proteins by this viral protease during infection; however, no large-scale HIV-1 protease degradomics study has yet been performed. To identify putative host substrates in an unbiased manner and on a proteome-wide scale, we used positional proteomics to identify peptides reporting protein processing by the HIV-1 protease, and a catalogue of over 120 cellular HIV-1 protease substrates processed in vitro was generated. This catalogue includes previously reported substrates as well as recently described interaction partners of HIV-1 proteins. Cleavage site alignments revealed a specificity profile in good correlation with previous studies, even though the ELLE consensus motif was not cleaved efficiently when incorporated into peptide substrates due to subsite cooperativity. Our results are further discussed in the context of HIV-1 infection and the complex substrate recognition by the viral protease.
Disruption of gingipain oligomerization into non-covalent cell-surface attached complexes
Authors: Sztukowska Maryta , Veillard Florian , Potempa Barbara , Bogyo Matthew , Enghild Jan J. , Thogersen Ida B. , Nguyen Ky-Anh , Potempa Jan
Published: August 2012

RgpA and Kgp gingipains are non-covalent complexes of endoprotease catalytic and hemagglutinin-adhesin domains on the surface of Porphyromonas gingivalis. A motif conserved in each domain has been suggested to function as an oligomerization motif. We tested this hypothesis by mutating motif residues to hexahistidine or insertion of hexahistidine tag to disrupt the motif within the Kgp catalytic domain. All modifications led to the secretion of entire Kgp activity into the growth media, predominantly in a form without functional His-tag. This confirmed the role of the conserved motif in correct posttranslational proteolytic processing and assembly of the multidomain complexes.
Adipose triglyceride lipase in immune response, inflammation, and atherosclerosis
Authors: Radovic Branislav , Aflaki Elma , Kratky Dagmar
Published: August 2012

Consistent with its central importance in lipid and energy homeostasis, lipolysis occurs in essentially all tissues and cell types, including macrophages. The hydrolytic cleavage of triacylglycerol by adipose triglyceride lipase (ATGL) generates non-esterified fatty acids, which are subsequently used as essential precursors for lipid and membrane synthesis, mediators in cell signaling processes or as energy substrate in mitochondria. This review summarizes the current knowledge concerning the consequences of ATGL deficiency in macrophages with particular emphasis on macrophage (dys)-function, apoptosis, and atherosclerosis.
The analysis of N-glycans of cell membrane proteins from human hematopoietic cell lines reveals distinctions in their pattern
Authors: Reinke Stefan O. , Bayer Marion , Berger Markus , Hinderlich Stephan , Blanchard Véronique
Published: August 2012

Human cell lines are often different in their features and present variations in the glycosylation patterns of cell membrane proteins. Protein glycosylation is the most common posttranslational modification and plays a particular role in functionality and bioactivity. The key approach of this study is the comparative analysis of five hematopoietic cell lines for their N-glycosylation pattern. The N-glycans of membrane proteins were elucidated by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and MALDI-TOF/TOF-MS analyses. Furthermore, the expression of a set of glycosyltransferases was determined via RT-PCR. The B-lymphoma BJA-B and promyelocytic HL-60 cell lines distinguish in levels and linkages of glycan-bound sialic acids. Furthermore, subclones of BJA-B and HL-60 cells, which completely lack UDP-N-acetylglucosamine 2-ēpimerase/N-acetylmannosamine kinase (GNE), the key enzyme of sialic acid biosynthesis, contained almost no sialylated N-glycans. Compared to wild-type cells, the GNE-deficient cells pres\xadented a similar cell surface N-glycosylation pattern in terms of antennarity and fucosylation. The Jurkat T-cell line revealed only partially sialylated N-glycans. Additionally, the different hematopoietic cell lines vary in their level of bisecting GlcNAcylation and antennary fucosylation with the quantities of bisecting N-acetylglucosamine (GlcNAc) and core fucose coinciding with the expression of GnT-III and FucT-VIII. Of note is the occurrence of N-acetyllactosamine (LacNAc) extensions on tetraantennary structures in GNE-deficient cell lines.
Effect of tenofovir, an antiretroviral drug, on hepatic and renal functional indices of Wistar rats: protective role of vitamin E
Authors: Adaramoye Oluwatosin Adekunle , Adewumi Olubusuyi Moses , Adesanoye Omolola Abidemi , Faokunla Opeyemi Olubunmi , Farombi Ebenezer Olatunde
Published: August 2012

Background: Tenofovir (TFR) is a nucleotide reverse transcriptase inhibitor with activity against human immunodeficiency virus. We studied the effect of TFR administered to Wistar rats on hepatic and renal function markers and the possible modulatory role of vitamin E (Vit E).

Methods: The study consists of four groups of six rats each. The first group served as control, the second group received TFR at 50 mg/kg/day for 4 weeks, third group received TFR and Vit E, and the last group received Vit E alone.

Results: TFR administration caused a significant (p<0.05) increase in the levels of serum urea, creatinine, urinary glucose, and protein by 65%, 51%, 88%, and 79%, respectively, relative to controls. This was followed by a significant (p<0.05) reduction in creatinine clearance of TFR-treated rats. There were no significant differences (p>0.05) in the activities of serum aminotransferases, γ-glutamyltransferase, and alkaline phosphatase in TRF-treated rats relative to controls. TFR administration caused a marked elevation of malondialdehyde (MDA; index of lipid peroxidation) in the animals. Specifically, serum, hepatic, and renal MDA levels increased by 75%, 90%, and 102%, respectively. TRF-treated rats had significantly (p<0.05) reduced activities of renal catalase, glutathione-S-transferase, and superoxide dismutase. Supplementation of Vit E ameliorated TFR-induced effects by decreasing the levels of MDA and enhancing the activities of renal antioxidative enzymes. The biochemical data were supported by histopathological findings from the slides.

Conclusions: TFR increased oxidative stress and altered kidney function markers in the rats, whereas supplementation of Vit E attenuated these effects.
Correlation between an absence of cervical gland area on transvaginal sonography and cervical mucus hyaluronic acid levels in women with threatened preterm delivery
Authors: Tateyama Naoko , Asakura Hirobumi , Takeshita Toshiyuki
Published: August 2012

Purpose: Transvaginal sonographic findings of an absent cervical gland area (CGA) and a short cervical length (CL) are frequently observed in patients with threatened preterm delivery. The present study aimed to clarify whether sonographic findings are due to active production of hyaluronic acid (HA) in the cervix.

Methods: Possible relationships between sonographic findings of the presence or absence of the CGA and/or a short CL and cervical mucus HA concentration were investigated in 68 women with threatened preterm delivery at 22–31 weeks’ gestation and 136 women without threatened preterm delivery as controls.

Results: HA levels were higher in women with threatened preterm delivery (68.0 ng/mL) than in controls (39.0 ng/mL; P=0.001). Similarly, HA levels were higher in women with preterm labor showing an absent CGA and a short CL than in women with threatened preterm delivery without such findings (P<0.01). Stepwise multivariate logistic regression identified an absent CGA and threatened preterm delivery as independent predictors of high HA levels (P=0.04). HA concentration was not predictive for preterm delivery.

Conclusion: A sonographic finding of an absent CGA reflects high HA levels in the cervix with threatened preterm delivery.
Young’s modulus and prediction of plastics/elastomer blends
Authors: Liang Ji-Zhao , Ma Wen-Yong
Published: August 2012

The tensile stress and strain under small deformation for plastics/elastomer blends were analyzed, based on a geometric model and mechanical element model, and a Young’s modulus equation was derived based on the hypothesis with equal strain and Hooke’s law. The polypropylene (PP)/polyolefin elastomer (POE) blends were prepared by means of a twin screw extruder, and the Young’s modulus was measured at room temperature. It was found that the Young’s modulus decreased nonlinearly with increase in the POE volume fraction. The Young’s modulus of the PP/POE blends was estimated using the equation and was compared with the measured data. There was good agreement between them. Moreover, the Young’s modulus of PP/ethylene propylene diene monomer (EPDM) rubber EPDM blends at room temperature was estimated respectively using this equation and the mingling rule equation, as well as Liang’s equation published in the literature. The results showed that the calculations with this equation were closer to the experimental data reported in reference than those with the other two equations.
Green composites based on recycled polyamide-6/recycled polypropylene kenaf composites: mechanical, thermal and morphological properties
Authors: Sukri Suhailah Mohd , Suradi Nor Liyana , Arsad Agus , Rahmat Abdul Razak , Hassan Azman
Published: August 2012

The objective of this work was to investigate the effect of kenaf contents on mechanical, thermal and morphological properties of recycled polyamide-6 (rPA-6)/recycled polypropylene (rPP) blends. Kenaf was used to enhance the properties of composites. Alkali treating of kenaf by sodium hydroxide (NaOH) and combination with propylene grafted maleic anhydride (PPgMA) as a compatibilizer produced good adhesion both between rPP and rPA-6, and rPA-6/rPP and kenaf. Tensile, flexural and Izod impact tests were evaluated to study the mechanical properties. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) tests were carried out to investigate thermal properties. Scanning electron microscopy (SEM) was performed for morphological analysis. Generally, the mechanical properties were successfully enhanced, especially Young’s modulus, flexural modulus, flexural strength and elongation at break, while there were some problems which caused the tensile strength and impact strength to be inferior. Thermal analysis showed that the crystallization of composites decreased as kenaf contents were increased. SEM showed a problem with kenaf and rPP/rPA-6 compatibility, which led to insufficient matrix at some places and agglomeration of kenaf at other places. Morphologically, there was unidirectional presence of kenaf in rPP main composites and random orientation in rPA-6 main composites.
Racial/Ethnic Differences in Infant Mortality Attributable to Birth Defects by Gestational Age
Authors: Broussard Cheryl S. , Gilboa Suzanne M. , Lee Kyung A. , Oster Matthew , Petrini Joann R. , Honein Margaret A.
Published: August 2012

OBJECTIVE:

Birth defects are a leading cause of infant mortality in the United States. Previous reports have highlighted black-white differences in overall infant mortality and infant mortality attributable to birth defects (IMBD). We evaluated the impact of gestational age on US racial/ethnic differences in IMBD.

METHODS:

We estimated the rate of IMBD as the underlying cause of death using the period-linked birth/infant death data for US residents for January 2003 to December 2006. We excluded infants with missing gestational age, implausible values based on Alexander’s index of birth weight for gestational age norms, or gestational ages <20 weeks or >44 weeks; we categorized gestational age into 3 groups: 20 to 33, 34 to 36, and 37 to 44 weeks. Using Poisson regression, we compared neonatal and postneonatal IMBD for infants of non-Hispanic black and Hispanic mothers with that for infants of non-Hispanic white mothers stratified by gestational age.

RESULTS:

IMBD occurred in 12.2 per 10 000 live births. Among infants delivered at 37 to 44 weeks, blacks (and Hispanics, to a lesser degree) had significantly higher neonatal and postneonatal IMBD than whites; however, among infants delivered at 20 to 33 or 34 to 36 weeks, neonatal (but not postneonatal) IMBD was significantly lower among blacks compared with whites.

CONCLUSIONS:

Racial/ethnic differences in IMBD were not explained in these data by differences in gestational age. Further investigation should include an assessment of possible racial/ethnic differences in severity and/or access to timely diagnosis and management of birth defects.
Unprovoked Status Epilepticus: The Prognosis for Otherwise Normal Children With Focal Epilepsy
Authors: Camfield Peter , Camfield Carol
Published: August 2012

OBJECTIVE:

To document the effect of unprovoked status epilepticus (SE) on the prognosis for otherwise normal children with focal epilepsy.

METHODS:

From the Nova Scotia Childhood Epilepsy Study (population-based), we identified patients with focal epilepsy, normal intelligence, and neurologic examination and follow-up ≥10 years. We compared those with and without unprovoked SE.

RESULTS:

One hundred eighty-eight cases had a mean follow-up of 27 ± 5 years with no deaths from SE. Thirty-nine (20%) had SE, 19 of whom experienced their first seizure. The number of episodes of SE was 1 in 27 patients (69%) and 2 to 10 in 12 patients. At onset 9 of 39 (23%) SE patients and 35 of 149 (23%) no-SE patients had specific learning disorders. At follow-up, 11 (28%) SE and 49 (33%) no-SE patients had learning disorders (P = not statistically different [ns]). Grades repeated, high school graduation, and advanced education did not differ. The number of antiepileptic drug (AED) used throughout the clinical course was the same: 22/39 (56%). SE patients used ≤2 AEDs versus 99 of 149 (64%) no-SE patients (P = .2). The distribution of patients using 3 to 11 AEDs was similar. The remission rate (seizure-free without AEDs at the end of follow-up) for SE patients was 24 of 39 (61%) versus 99 of 149 (66%) in no-SE (P = .5). Intractable epilepsy occurred in 15% SE and 11% of no-SE cases.

CONCLUSIONS:

SE often recurs but apparently has little influence on long-term intellectual and seizure outcome in normally intelligent children with focal epilepsy.
The Relationship Between Dating Violence and Suicidal Behaviors in a National Sample of Adolescents
Authors: Belshaw Scott H. , Siddique Julie Ahmad , Tanner Jennifer , Osho G. Solomon
Published: August 2012

Relationship violence is a common problem faced by adolescents in the United States. In general, adolescents are at higher risk for relationship victimization than adults (Silverman, Raj, Mucci, & Hathaway, 2001), and females between the ages of 16 and 24 years are at the highest risk of relationship victimization (Rennison, 2001). This study uses data from the 2007 Youth Risk Behavior Surveillance (YRBSS) System (or referred to as Youth Risk Behavior Survey [YRBS]; N = 11,781) of adolescents between the ages of 14 and 17 years to estimate two logistic regression models on the association between relationship violence and suicidal behaviors controlling for variables such as sexual assault and drug use. The findings indicated that victimized adolescents are at higher risk for planning and/or attempting suicide compared to nonvictimized adolescents. Implications for research and practice are explored.
Bayesian inference analysis of the uncertainty linked to the evaluation of potential flood damage in urban areas
Authors: Fontanazza C. M. , Freni G. , Notaro V.
Published: August 2012

Flood damage in urbanized watersheds may be assessed by combining the flood depth–damage curves and the outputs of urban flood models. The complexity of the physical processes that must be simulated and the limited amount of data available for model calibration may lead to high uncertainty in the model results and consequently in damage estimation. Moreover depth–damage functions are usually affected by significant uncertainty related to the collected data and to the simplified structure of the regression law that is used. The present paper carries out the analysis of the uncertainty connected to the flood damage estimate obtained combining the use of hydraulic models and depth–damage curves. A Bayesian inference analysis was proposed along with a probabilistic approach for the parameters estimating. The analysis demonstrated that the Bayesian approach is very effective considering that the available databases are usually short.
The future European standard to determine odour in ambient air by using field inspection
Authors: Guillot J. M. , Bilsen I. , Both R. , Hangartner M. , Kost W. J. , Kunz W. , Nicolas J. , Oxbol A. , Secanella J. , Van Belois H. , Van Elst T. , Van Harreveld T. , Milan B.
Published: August 2012

This paper presents the methodologies to determine odour in ambient air by field inspection that will be a new European standard. The objective is to characterise the odour in a defined area. Without making a link with potential annoyance due to the presence of odours, the described methods propose the way to characterise an exposed environment. Two approaches are defined in the new standard: the grid method and the plume method. The grid method can be used to determine the exposure to ambient odours in a defined area of study, using direct observation of recognisable odours in the field by human panel members. This method must be applied over a sufficiently long period of time (6 or 12 months) to be representative of the meteorological conditions of that location. The result is the distribution of the frequency of exposure to odours within the assessment area. The plume method can be used to determine the extent of detectable and recognisable odours from a specific source using direct observation in the field by human panel members under specific meteorological conditions.
High-power, high-beam-quality solid-state lasers for materials processing applications
Authors: Hackel Lloyd A. , Dane C. Brent , Hermann Mark R. , Honig John , Zapata Luis E. , Norton Mary A.
Published: August 2012

The Laser Science and Technology Department at Lawrence Livermore National Laboratory is developing solid-state lasers with high average power and high beam quality. Specific systems include a laser to generate 1.0–1.4 nm X-rays for proximity print lithography, a 400-mJ, 500-Hz laser for 13.0 nm projection lithography and unique systems for speckle imaging, laser radars, and medical treatments.